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c609719b 1#
eca3aeb3 2# (C) Copyright 2000 - 2013
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3# Wolfgang Denk, DENX Software Engineering, [email protected].
4#
eca3aeb3 5# SPDX-License-Identifier: GPL-2.0+
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6#
7
8Summary:
9========
10
24ee89b9 11This directory contains the source code for U-Boot, a boot loader for
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12Embedded boards based on PowerPC, ARM, MIPS and several other
13processors, which can be installed in a boot ROM and used to
14initialize and test the hardware or to download and run application
15code.
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16
17The development of U-Boot is closely related to Linux: some parts of
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18the source code originate in the Linux source tree, we have some
19header files in common, and special provision has been made to
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20support booting of Linux images.
21
22Some attention has been paid to make this software easily
23configurable and extendable. For instance, all monitor commands are
24implemented with the same call interface, so that it's very easy to
25add new commands. Also, instead of permanently adding rarely used
26code (for instance hardware test utilities) to the monitor, you can
27load and run it dynamically.
28
29
30Status:
31=======
32
33In general, all boards for which a configuration option exists in the
24ee89b9 34Makefile have been tested to some extent and can be considered
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35"working". In fact, many of them are used in production systems.
36
24ee89b9 37In case of problems see the CHANGELOG and CREDITS files to find out
27af930e 38who contributed the specific port. The boards.cfg file lists board
218ca724 39maintainers.
c609719b 40
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41Note: There is no CHANGELOG file in the actual U-Boot source tree;
42it can be created dynamically from the Git log using:
43
44 make CHANGELOG
45
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46
47Where to get help:
48==================
49
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50In case you have questions about, problems with or contributions for
51U-Boot you should send a message to the U-Boot mailing list at
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52<[email protected]>. There is also an archive of previous traffic
53on the mailing list - please search the archive before asking FAQ's.
54Please see http://lists.denx.de/pipermail/u-boot and
55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
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56
57
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58Where to get source code:
59=========================
60
61The U-Boot source code is maintained in the git repository at
62git://www.denx.de/git/u-boot.git ; you can browse it online at
63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
64
65The "snapshot" links on this page allow you to download tarballs of
11ccc33f 66any version you might be interested in. Official releases are also
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67available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
68directory.
69
d4ee711d 70Pre-built (and tested) images are available from
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71ftp://ftp.denx.de/pub/u-boot/images/
72
73
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74Where we come from:
75===================
76
77- start from 8xxrom sources
24ee89b9 78- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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79- clean up code
80- make it easier to add custom boards
81- make it possible to add other [PowerPC] CPUs
82- extend functions, especially:
83 * Provide extended interface to Linux boot loader
84 * S-Record download
85 * network boot
11ccc33f 86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
24ee89b9 87- create ARMBoot project (http://sourceforge.net/projects/armboot)
c609719b 88- add other CPU families (starting with ARM)
24ee89b9 89- create U-Boot project (http://sourceforge.net/projects/u-boot)
0d28f34b 90- current project page: see http://www.denx.de/wiki/U-Boot
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91
92
93Names and Spelling:
94===================
95
96The "official" name of this project is "Das U-Boot". The spelling
97"U-Boot" shall be used in all written text (documentation, comments
98in source files etc.). Example:
99
100 This is the README file for the U-Boot project.
101
102File names etc. shall be based on the string "u-boot". Examples:
103
104 include/asm-ppc/u-boot.h
105
106 #include <asm/u-boot.h>
107
108Variable names, preprocessor constants etc. shall be either based on
109the string "u_boot" or on "U_BOOT". Example:
110
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
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113
114
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115Versioning:
116===========
117
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118Starting with the release in October 2008, the names of the releases
119were changed from numerical release numbers without deeper meaning
120into a time stamp based numbering. Regular releases are identified by
121names consisting of the calendar year and month of the release date.
122Additional fields (if present) indicate release candidates or bug fix
123releases in "stable" maintenance trees.
124
125Examples:
c0f40859 126 U-Boot v2009.11 - Release November 2009
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127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
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129
130
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131Directory Hierarchy:
132====================
133
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134/arch Architecture specific files
135 /arm Files generic to ARM architecture
136 /cpu CPU specific files
137 /arm720t Files specific to ARM 720 CPUs
138 /arm920t Files specific to ARM 920 CPUs
6eb0921a 139 /at91 Files specific to Atmel AT91RM9200 CPU
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140 /imx Files specific to Freescale MC9328 i.MX CPUs
141 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
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142 /arm926ejs Files specific to ARM 926 CPUs
143 /arm1136 Files specific to ARM 1136 CPUs
8d321b81 144 /pxa Files specific to Intel XScale PXA CPUs
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145 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
146 /lib Architecture specific library files
147 /avr32 Files generic to AVR32 architecture
148 /cpu CPU specific files
149 /lib Architecture specific library files
150 /blackfin Files generic to Analog Devices Blackfin architecture
151 /cpu CPU specific files
152 /lib Architecture specific library files
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153 /m68k Files generic to m68k architecture
154 /cpu CPU specific files
155 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
156 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
157 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
158 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
159 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
160 /lib Architecture specific library files
161 /microblaze Files generic to microblaze architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /mips Files generic to MIPS architecture
165 /cpu CPU specific files
92bbd64e 166 /mips32 Files specific to MIPS32 CPUs
80421fcc 167 /xburst Files specific to Ingenic XBurst CPUs
8d321b81 168 /lib Architecture specific library files
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169 /nds32 Files generic to NDS32 architecture
170 /cpu CPU specific files
171 /n1213 Files specific to Andes Technology N1213 CPUs
172 /lib Architecture specific library files
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173 /nios2 Files generic to Altera NIOS2 architecture
174 /cpu CPU specific files
175 /lib Architecture specific library files
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176 /openrisc Files generic to OpenRISC architecture
177 /cpu CPU specific files
178 /lib Architecture specific library files
a47a12be 179 /powerpc Files generic to PowerPC architecture
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180 /cpu CPU specific files
181 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
182 /mpc5xx Files specific to Freescale MPC5xx CPUs
183 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
184 /mpc8xx Files specific to Freescale MPC8xx CPUs
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185 /mpc824x Files specific to Freescale MPC824x CPUs
186 /mpc8260 Files specific to Freescale MPC8260 CPUs
187 /mpc85xx Files specific to Freescale MPC85xx CPUs
188 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
189 /lib Architecture specific library files
190 /sh Files generic to SH architecture
191 /cpu CPU specific files
192 /sh2 Files specific to sh2 CPUs
193 /sh3 Files specific to sh3 CPUs
194 /sh4 Files specific to sh4 CPUs
195 /lib Architecture specific library files
196 /sparc Files generic to SPARC architecture
197 /cpu CPU specific files
198 /leon2 Files specific to Gaisler LEON2 SPARC CPU
199 /leon3 Files specific to Gaisler LEON3 SPARC CPU
200 /lib Architecture specific library files
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201 /x86 Files generic to x86 architecture
202 /cpu CPU specific files
203 /lib Architecture specific library files
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204/api Machine/arch independent API for external apps
205/board Board dependent files
206/common Misc architecture independent functions
207/disk Code for disk drive partition handling
208/doc Documentation (don't expect too much)
209/drivers Commonly used device drivers
33c7731b 210/dts Contains Makefile for building internal U-Boot fdt.
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211/examples Example code for standalone applications, etc.
212/fs Filesystem code (cramfs, ext2, jffs2, etc.)
213/include Header Files
214/lib Files generic to all architectures
215 /libfdt Library files to support flattened device trees
216 /lzma Library files to support LZMA decompression
217 /lzo Library files to support LZO decompression
218/net Networking code
219/post Power On Self Test
33c7731b 220/spl Secondary Program Loader framework
8d321b81 221/tools Tools to build S-Record or U-Boot images, etc.
c609719b 222
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223Software Configuration:
224=======================
225
226Configuration is usually done using C preprocessor defines; the
227rationale behind that is to avoid dead code whenever possible.
228
229There are two classes of configuration variables:
230
231* Configuration _OPTIONS_:
232 These are selectable by the user and have names beginning with
233 "CONFIG_".
234
235* Configuration _SETTINGS_:
236 These depend on the hardware etc. and should not be meddled with if
237 you don't know what you're doing; they have names beginning with
6d0f6bcf 238 "CONFIG_SYS_".
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239
240Later we will add a configuration tool - probably similar to or even
241identical to what's used for the Linux kernel. Right now, we have to
242do the configuration by hand, which means creating some symbolic
243links and editing some configuration files. We use the TQM8xxL boards
244as an example here.
245
246
247Selection of Processor Architecture and Board Type:
248---------------------------------------------------
249
250For all supported boards there are ready-to-use default
251configurations available; just type "make <board_name>_config".
252
253Example: For a TQM823L module type:
254
255 cd u-boot
256 make TQM823L_config
257
11ccc33f 258For the Cogent platform, you need to specify the CPU type as well;
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259e.g. "make cogent_mpc8xx_config". And also configure the cogent
260directory according to the instructions in cogent/README.
261
262
263Configuration Options:
264----------------------
265
266Configuration depends on the combination of board and CPU type; all
267such information is kept in a configuration file
268"include/configs/<board_name>.h".
269
270Example: For a TQM823L module, all configuration settings are in
271"include/configs/TQM823L.h".
272
273
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274Many of the options are named exactly as the corresponding Linux
275kernel configuration options. The intention is to make it easier to
276build a config tool - later.
277
278
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279The following options need to be configured:
280
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281- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
282
283- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
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284
285- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
09ea0de0 286 Define exactly one, e.g. CONFIG_ATSTK1002
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287
288- CPU Module Type: (if CONFIG_COGENT is defined)
289 Define exactly one of
290 CONFIG_CMA286_60_OLD
291--- FIXME --- not tested yet:
292 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
293 CONFIG_CMA287_23, CONFIG_CMA287_50
294
295- Motherboard Type: (if CONFIG_COGENT is defined)
296 Define exactly one of
297 CONFIG_CMA101, CONFIG_CMA102
298
299- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
300 Define one or more of
301 CONFIG_CMA302
302
303- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
304 Define one or more of
305 CONFIG_LCD_HEARTBEAT - update a character position on
11ccc33f 306 the LCD display every second with
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307 a "rotator" |\-/|\-/
308
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309- Board flavour: (if CONFIG_MPC8260ADS is defined)
310 CONFIG_ADSTYPE
311 Possible values are:
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312 CONFIG_SYS_8260ADS - original MPC8260ADS
313 CONFIG_SYS_8266ADS - MPC8266ADS
314 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
315 CONFIG_SYS_8272ADS - MPC8272ADS
2535d602 316
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317- Marvell Family Member
318 CONFIG_SYS_MVFS - define it if you want to enable
319 multiple fs option at one time
320 for marvell soc family
321
c609719b 322- MPC824X Family Member (if CONFIG_MPC824X is defined)
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323 Define exactly one of
324 CONFIG_MPC8240, CONFIG_MPC8245
c609719b 325
11ccc33f 326- 8xx CPU Options: (if using an MPC8xx CPU)
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327 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
328 get_gclk_freq() cannot work
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329 e.g. if there is no 32KHz
330 reference PIT/RTC clock
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331 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
332 or XTAL/EXTAL)
c609719b 333
66ca92a5 334- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
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335 CONFIG_SYS_8xx_CPUCLK_MIN
336 CONFIG_SYS_8xx_CPUCLK_MAX
66ca92a5 337 CONFIG_8xx_CPUCLK_DEFAULT
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338 See doc/README.MPC866
339
6d0f6bcf 340 CONFIG_SYS_MEASURE_CPUCLK
75d1ea7f 341
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342 Define this to measure the actual CPU clock instead
343 of relying on the correctness of the configured
344 values. Mostly useful for board bringup to make sure
345 the PLL is locked at the intended frequency. Note
346 that this requires a (stable) reference clock (32 kHz
6d0f6bcf 347 RTC clock or CONFIG_SYS_8XX_XIN)
75d1ea7f 348
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349 CONFIG_SYS_DELAYED_ICACHE
350
351 Define this option if you want to enable the
352 ICache only when Code runs from RAM.
353
66412c63 354- 85xx CPU Options:
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355 CONFIG_SYS_PPC64
356
357 Specifies that the core is a 64-bit PowerPC implementation (implements
358 the "64" category of the Power ISA). This is necessary for ePAPR
359 compliance, among other possible reasons.
360
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361 CONFIG_SYS_FSL_TBCLK_DIV
362
363 Defines the core time base clock divider ratio compared to the
364 system clock. On most PQ3 devices this is 8, on newer QorIQ
365 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366
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367 CONFIG_SYS_FSL_PCIE_COMPAT
368
369 Defines the string to utilize when trying to match PCIe device
370 tree nodes for the given platform.
371
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372 CONFIG_SYS_PPC_E500_DEBUG_TLB
373
374 Enables a temporary TLB entry to be used during boot to work
375 around limitations in e500v1 and e500v2 external debugger
376 support. This reduces the portions of the boot code where
377 breakpoints and single stepping do not work. The value of this
378 symbol should be set to the TLB1 entry to be used for this
379 purpose.
380
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381 CONFIG_SYS_FSL_ERRATUM_A004510
382
383 Enables a workaround for erratum A004510. If set,
384 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
385 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
386
387 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
388 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
389
390 Defines one or two SoC revisions (low 8 bits of SVR)
391 for which the A004510 workaround should be applied.
392
393 The rest of SVR is either not relevant to the decision
394 of whether the erratum is present (e.g. p2040 versus
395 p2041) or is implied by the build target, which controls
396 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
397
398 See Freescale App Note 4493 for more information about
399 this erratum.
400
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401 CONFIG_A003399_NOR_WORKAROUND
402 Enables a workaround for IFC erratum A003399. It is only
403 requred during NOR boot.
404
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405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
406
407 This is the value to write into CCSR offset 0x18600
408 according to the A004510 workaround.
409
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410 CONFIG_SYS_FSL_DSP_DDR_ADDR
411 This value denotes start offset of DDR memory which is
412 connected exclusively to the DSP cores.
413
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414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
415 This value denotes start offset of M2 memory
416 which is directly connected to the DSP core.
417
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418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
419 This value denotes start offset of M3 memory which is directly
420 connected to the DSP core.
421
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422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
423 This value denotes start offset of DSP CCSR space.
424
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425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
426 Single Source Clock is clocking mode present in some of FSL SoC's.
427 In this mode, a single differential clock is used to supply
428 clocks to the sysclock, ddrclock and usbclock.
429
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430- Generic CPU options:
431 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
432
433 Defines the endianess of the CPU. Implementation of those
434 values is arch specific.
435
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436 CONFIG_SYS_FSL_DDR
437 Freescale DDR driver in use. This type of DDR controller is
438 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
439 SoCs.
440
441 CONFIG_SYS_FSL_DDR_ADDR
442 Freescale DDR memory-mapped register base.
443
444 CONFIG_SYS_FSL_DDR_EMU
445 Specify emulator support for DDR. Some DDR features such as
446 deskew training are not available.
447
448 CONFIG_SYS_FSL_DDRC_GEN1
449 Freescale DDR1 controller.
450
451 CONFIG_SYS_FSL_DDRC_GEN2
452 Freescale DDR2 controller.
453
454 CONFIG_SYS_FSL_DDRC_GEN3
455 Freescale DDR3 controller.
456
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457 CONFIG_SYS_FSL_DDRC_ARM_GEN3
458 Freescale DDR3 controller for ARM-based SoCs.
459
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460 CONFIG_SYS_FSL_DDR1
461 Board config to use DDR1. It can be enabled for SoCs with
462 Freescale DDR1 or DDR2 controllers, depending on the board
463 implemetation.
464
465 CONFIG_SYS_FSL_DDR2
466 Board config to use DDR2. It can be eanbeld for SoCs with
467 Freescale DDR2 or DDR3 controllers, depending on the board
468 implementation.
469
470 CONFIG_SYS_FSL_DDR3
471 Board config to use DDR3. It can be enabled for SoCs with
472 Freescale DDR3 controllers.
473
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474 CONFIG_SYS_FSL_IFC_BE
475 Defines the IFC controller register space as Big Endian
476
477 CONFIG_SYS_FSL_IFC_LE
478 Defines the IFC controller register space as Little Endian
479
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480 CONFIG_SYS_FSL_PBL_PBI
481 It enables addition of RCW (Power on reset configuration) in built image.
482 Please refer doc/README.pblimage for more details
483
484 CONFIG_SYS_FSL_PBL_RCW
485 It adds PBI(pre-boot instructions) commands in u-boot build image.
486 PBI commands can be used to configure SoC before it starts the execution.
487 Please refer doc/README.pblimage for more details
488
0b953ffc 489- Intel Monahans options:
6d0f6bcf 490 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
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491
492 Defines the Monahans run mode to oscillator
493 ratio. Valid values are 8, 16, 24, 31. The core
494 frequency is this value multiplied by 13 MHz.
495
6d0f6bcf 496 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
cf48eb9a 497
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498 Defines the Monahans turbo mode to oscillator
499 ratio. Valid values are 1 (default if undefined) and
cf48eb9a 500 2. The core frequency as calculated above is multiplied
0b953ffc 501 by this value.
cf48eb9a 502
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503- MIPS CPU options:
504 CONFIG_SYS_INIT_SP_OFFSET
505
506 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
507 pointer. This is needed for the temporary stack before
508 relocation.
509
510 CONFIG_SYS_MIPS_CACHE_MODE
511
512 Cache operation mode for the MIPS CPU.
513 See also arch/mips/include/asm/mipsregs.h.
514 Possible values are:
515 CONF_CM_CACHABLE_NO_WA
516 CONF_CM_CACHABLE_WA
517 CONF_CM_UNCACHED
518 CONF_CM_CACHABLE_NONCOHERENT
519 CONF_CM_CACHABLE_CE
520 CONF_CM_CACHABLE_COW
521 CONF_CM_CACHABLE_CUW
522 CONF_CM_CACHABLE_ACCELERATED
523
524 CONFIG_SYS_XWAY_EBU_BOOTCFG
525
526 Special option for Lantiq XWAY SoCs for booting from NOR flash.
527 See also arch/mips/cpu/mips32/start.S.
528
529 CONFIG_XWAY_SWAP_BYTES
530
531 Enable compilation of tools/xway-swap-bytes needed for Lantiq
532 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
533 be swapped if a flash programmer is used.
534
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535- ARM options:
536 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
537
538 Select high exception vectors of the ARM core, e.g., do not
539 clear the V bit of the c1 register of CP15.
540
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541 CONFIG_SYS_THUMB_BUILD
542
543 Use this flag to build U-Boot using the Thumb instruction
544 set for ARM architectures. Thumb instruction set provides
545 better code density. For ARM architectures that support
546 Thumb2 this flag will result in Thumb2 code generated by
547 GCC.
548
c5d4752c 549 CONFIG_ARM_ERRATA_716044
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550 CONFIG_ARM_ERRATA_742230
551 CONFIG_ARM_ERRATA_743622
552 CONFIG_ARM_ERRATA_751472
553
554 If set, the workarounds for these ARM errata are applied early
555 during U-Boot startup. Note that these options force the
556 workarounds to be applied; no CPU-type/version detection
557 exists, unlike the similar options in the Linux kernel. Do not
558 set these options unless they apply!
559
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560- CPU timer options:
561 CONFIG_SYS_HZ
562
563 The frequency of the timer returned by get_timer().
564 get_timer() must operate in milliseconds and this CONFIG
565 option must be set to 1000.
566
5da627a4 567- Linux Kernel Interface:
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568 CONFIG_CLOCKS_IN_MHZ
569
570 U-Boot stores all clock information in Hz
571 internally. For binary compatibility with older Linux
572 kernels (which expect the clocks passed in the
573 bd_info data to be in MHz) the environment variable
574 "clocks_in_mhz" can be defined so that U-Boot
575 converts clock data to MHZ before passing it to the
576 Linux kernel.
c609719b 577 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
218ca724 578 "clocks_in_mhz=1" is automatically included in the
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579 default environment.
580
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581 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
582
11ccc33f 583 When transferring memsize parameter to linux, some versions
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584 expect it to be in bytes, others in MB.
585 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
586
fec6d9ee 587 CONFIG_OF_LIBFDT
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588
589 New kernel versions are expecting firmware settings to be
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590 passed using flattened device trees (based on open firmware
591 concepts).
592
593 CONFIG_OF_LIBFDT
594 * New libfdt-based support
595 * Adds the "fdt" command
3bb342fc 596 * The bootm command automatically updates the fdt
213bf8c8 597
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598 OF_CPU - The proper name of the cpus node (only required for
599 MPC512X and MPC5xxx based boards).
600 OF_SOC - The proper name of the soc node (only required for
601 MPC512X and MPC5xxx based boards).
f57f70aa 602 OF_TBCLK - The timebase frequency.
c2871f03 603 OF_STDOUT_PATH - The path to the console device
f57f70aa 604
11ccc33f
MZ
605 boards with QUICC Engines require OF_QE to set UCC MAC
606 addresses
3bb342fc 607
4e253137
KG
608 CONFIG_OF_BOARD_SETUP
609
610 Board code has addition modification that it wants to make
611 to the flat device tree before handing it off to the kernel
f57f70aa 612
0267768e
MM
613 CONFIG_OF_BOOT_CPU
614
11ccc33f 615 This define fills in the correct boot CPU in the boot
0267768e
MM
616 param header, the default value is zero if undefined.
617
3887c3fb
HS
618 CONFIG_OF_IDE_FIXUP
619
620 U-Boot can detect if an IDE device is present or not.
621 If not, and this new config option is activated, U-Boot
622 removes the ATA node from the DTS before booting Linux,
623 so the Linux IDE driver does not probe the device and
624 crash. This is needed for buggy hardware (uc101) where
625 no pull down resistor is connected to the signal IDE5V_DD7.
626
7eb29398
IG
627 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
628
629 This setting is mandatory for all boards that have only one
630 machine type and must be used to specify the machine type
631 number as it appears in the ARM machine registry
632 (see http://www.arm.linux.org.uk/developer/machines/).
633 Only boards that have multiple machine types supported
634 in a single configuration file and the machine type is
635 runtime discoverable, do not have to use this setting.
636
0b2f4eca
NG
637- vxWorks boot parameters:
638
639 bootvx constructs a valid bootline using the following
640 environments variables: bootfile, ipaddr, serverip, hostname.
641 It loads the vxWorks image pointed bootfile.
642
643 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
644 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
645 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
646 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
647
648 CONFIG_SYS_VXWORKS_ADD_PARAMS
649
650 Add it at the end of the bootline. E.g "u=username pw=secret"
651
652 Note: If a "bootargs" environment is defined, it will overwride
653 the defaults discussed just above.
654
2c451f78
A
655- Cache Configuration:
656 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
657 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
658 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
659
93bc2193
A
660- Cache Configuration for ARM:
661 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
662 controller
663 CONFIG_SYS_PL310_BASE - Physical base address of PL310
664 controller register space
665
6705d81e 666- Serial Ports:
48d0192f 667 CONFIG_PL010_SERIAL
6705d81e
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668
669 Define this if you want support for Amba PrimeCell PL010 UARTs.
670
48d0192f 671 CONFIG_PL011_SERIAL
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672
673 Define this if you want support for Amba PrimeCell PL011 UARTs.
674
675 CONFIG_PL011_CLOCK
676
677 If you have Amba PrimeCell PL011 UARTs, set this variable to
678 the clock speed of the UARTs.
679
680 CONFIG_PL01x_PORTS
681
682 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
683 define this to a list of base addresses for each (supported)
684 port. See e.g. include/configs/versatile.h
685
910f1ae3
JR
686 CONFIG_PL011_SERIAL_RLCR
687
688 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
689 have separate receive and transmit line control registers. Set
690 this variable to initialize the extra register.
691
692 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
693
694 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
695 boot loader that has already initialized the UART. Define this
696 variable to flush the UART at init time.
697
6705d81e 698
c609719b 699- Console Interface:
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700 Depending on board, define exactly one serial port
701 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
702 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
703 console by defining CONFIG_8xx_CONS_NONE
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704
705 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
706 port routines must be defined elsewhere
707 (i.e. serial_init(), serial_getc(), ...)
708
709 CONFIG_CFB_CONSOLE
710 Enables console device for a color framebuffer. Needs following
c53043b7 711 defines (cf. smiLynxEM, i8042)
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712 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
713 (default big endian)
714 VIDEO_HW_RECTFILL graphic chip supports
715 rectangle fill
716 (cf. smiLynxEM)
717 VIDEO_HW_BITBLT graphic chip supports
718 bit-blit (cf. smiLynxEM)
719 VIDEO_VISIBLE_COLS visible pixel columns
720 (cols=pitch)
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721 VIDEO_VISIBLE_ROWS visible pixel rows
722 VIDEO_PIXEL_SIZE bytes per pixel
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723 VIDEO_DATA_FORMAT graphic data format
724 (0-5, cf. cfb_console.c)
ba56f625 725 VIDEO_FB_ADRS framebuffer address
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726 VIDEO_KBD_INIT_FCT keyboard int fct
727 (i.e. i8042_kbd_init())
728 VIDEO_TSTC_FCT test char fct
729 (i.e. i8042_tstc)
730 VIDEO_GETC_FCT get char fct
731 (i.e. i8042_getc)
732 CONFIG_CONSOLE_CURSOR cursor drawing on/off
733 (requires blink timer
734 cf. i8042.c)
6d0f6bcf 735 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
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736 CONFIG_CONSOLE_TIME display time/date info in
737 upper right corner
602ad3b3 738 (requires CONFIG_CMD_DATE)
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739 CONFIG_VIDEO_LOGO display Linux logo in
740 upper left corner
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741 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
742 linux_logo.h for logo.
743 Requires CONFIG_VIDEO_LOGO
c609719b 744 CONFIG_CONSOLE_EXTRA_INFO
11ccc33f 745 additional board info beside
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WD
746 the logo
747
33a35bbb
T
748 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
749 a limited number of ANSI escape sequences (cursor control,
750 erase functions and limited graphics rendition control).
751
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752 When CONFIG_CFB_CONSOLE is defined, video console is
753 default i/o. Serial console can be forced with
754 environment 'console=serial'.
c609719b 755
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756 When CONFIG_SILENT_CONSOLE is defined, all console
757 messages (by U-Boot and Linux!) can be silenced with
758 the "silent" environment variable. See
759 doc/README.silent for more information.
a3ad8e26 760
45ae2546
HS
761 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
762 is 0x00.
763 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
764 is 0xa0.
765
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766- Console Baudrate:
767 CONFIG_BAUDRATE - in bps
768 Select one of the baudrates listed in
6d0f6bcf
JCPV
769 CONFIG_SYS_BAUDRATE_TABLE, see below.
770 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
c609719b 771
c92fac91
HS
772- Console Rx buffer length
773 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
774 the maximum receive buffer length for the SMC.
2b3f12c2 775 This option is actual only for 82xx and 8xx possible.
c92fac91
HS
776 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
777 must be defined, to setup the maximum idle timeout for
778 the SMC.
779
9558b48a 780- Pre-Console Buffer:
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WD
781 Prior to the console being initialised (i.e. serial UART
782 initialised etc) all console output is silently discarded.
783 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
784 buffer any console messages prior to the console being
785 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
786 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
787 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
6feff899 788 bytes are output before the console is initialised, the
4cf2609b
WD
789 earlier bytes are discarded.
790
791 'Sane' compilers will generate smaller code if
792 CONFIG_PRE_CON_BUF_SZ is a power of 2
9558b48a 793
046a37bd
SR
794- Safe printf() functions
795 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
796 the printf() functions. These are defined in
797 include/vsprintf.h and include snprintf(), vsnprintf() and
798 so on. Code size increase is approximately 300-500 bytes.
799 If this option is not given then these functions will
800 silently discard their buffer size argument - this means
801 you are not getting any overflow checking in this case.
802
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WD
803- Boot Delay: CONFIG_BOOTDELAY - in seconds
804 Delay before automatically booting the default image;
805 set to -1 to disable autoboot.
93d7212f
JH
806 set to -2 to autoboot with no delay and not check for abort
807 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
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808
809 See doc/README.autoboot for these options that
810 work with CONFIG_BOOTDELAY. None are required.
811 CONFIG_BOOT_RETRY_TIME
812 CONFIG_BOOT_RETRY_MIN
813 CONFIG_AUTOBOOT_KEYED
814 CONFIG_AUTOBOOT_PROMPT
815 CONFIG_AUTOBOOT_DELAY_STR
816 CONFIG_AUTOBOOT_STOP_STR
817 CONFIG_AUTOBOOT_DELAY_STR2
818 CONFIG_AUTOBOOT_STOP_STR2
819 CONFIG_ZERO_BOOTDELAY_CHECK
820 CONFIG_RESET_TO_RETRY
821
822- Autoboot Command:
823 CONFIG_BOOTCOMMAND
824 Only needed when CONFIG_BOOTDELAY is enabled;
825 define a command string that is automatically executed
826 when no character is read on the console interface
827 within "Boot Delay" after reset.
828
829 CONFIG_BOOTARGS
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WD
830 This can be used to pass arguments to the bootm
831 command. The value of CONFIG_BOOTARGS goes into the
832 environment value "bootargs".
c609719b
WD
833
834 CONFIG_RAMBOOT and CONFIG_NFSBOOT
43d9616c
WD
835 The value of these goes into the environment as
836 "ramboot" and "nfsboot" respectively, and can be used
837 as a convenience, when switching between booting from
11ccc33f 838 RAM and NFS.
c609719b 839
eda0ba38
HS
840- Bootcount:
841 CONFIG_BOOTCOUNT_LIMIT
842 Implements a mechanism for detecting a repeating reboot
843 cycle, see:
844 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
845
846 CONFIG_BOOTCOUNT_ENV
847 If no softreset save registers are found on the hardware
848 "bootcount" is stored in the environment. To prevent a
849 saveenv on all reboots, the environment variable
850 "upgrade_available" is used. If "upgrade_available" is
851 0, "bootcount" is always 0, if "upgrade_available" is
852 1 "bootcount" is incremented in the environment.
853 So the Userspace Applikation must set the "upgrade_available"
854 and "bootcount" variable to 0, if a boot was successfully.
855
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WD
856- Pre-Boot Commands:
857 CONFIG_PREBOOT
858
859 When this option is #defined, the existence of the
860 environment variable "preboot" will be checked
861 immediately before starting the CONFIG_BOOTDELAY
862 countdown and/or running the auto-boot command resp.
863 entering interactive mode.
864
865 This feature is especially useful when "preboot" is
866 automatically generated or modified. For an example
867 see the LWMON board specific code: here "preboot" is
868 modified when the user holds down a certain
869 combination of keys on the (special) keyboard when
870 booting the systems
871
872- Serial Download Echo Mode:
873 CONFIG_LOADS_ECHO
874 If defined to 1, all characters received during a
875 serial download (using the "loads" command) are
876 echoed back. This might be needed by some terminal
877 emulations (like "cu"), but may as well just take
878 time on others. This setting #define's the initial
879 value of the "loads_echo" environment variable.
880
602ad3b3 881- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
c609719b
WD
882 CONFIG_KGDB_BAUDRATE
883 Select one of the baudrates listed in
6d0f6bcf 884 CONFIG_SYS_BAUDRATE_TABLE, see below.
c609719b
WD
885
886- Monitor Functions:
602ad3b3
JL
887 Monitor commands can be included or excluded
888 from the build by using the #include files
c6c621bd
SW
889 <config_cmd_all.h> and #undef'ing unwanted
890 commands, or using <config_cmd_default.h>
602ad3b3
JL
891 and augmenting with additional #define's
892 for wanted commands.
893
894 The default command configuration includes all commands
895 except those marked below with a "*".
896
897 CONFIG_CMD_ASKENV * ask for env variable
602ad3b3
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898 CONFIG_CMD_BDI bdinfo
899 CONFIG_CMD_BEDBUG * Include BedBug Debugger
900 CONFIG_CMD_BMP * BMP support
901 CONFIG_CMD_BSP * Board specific commands
902 CONFIG_CMD_BOOTD bootd
903 CONFIG_CMD_CACHE * icache, dcache
08d0d6f3 904 CONFIG_CMD_CLK * clock command support
602ad3b3 905 CONFIG_CMD_CONSOLE coninfo
710b9938 906 CONFIG_CMD_CRC32 * crc32
602ad3b3
JL
907 CONFIG_CMD_DATE * support for RTC, date/time...
908 CONFIG_CMD_DHCP * DHCP support
909 CONFIG_CMD_DIAG * Diagnostics
a7c93104
PT
910 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
911 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
912 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
913 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
602ad3b3
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914 CONFIG_CMD_DTT * Digital Therm and Thermostat
915 CONFIG_CMD_ECHO echo arguments
246c6922 916 CONFIG_CMD_EDITENV edit env variable
602ad3b3
JL
917 CONFIG_CMD_EEPROM * EEPROM read/write support
918 CONFIG_CMD_ELF * bootelf, bootvx
5e2b3e0c 919 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
fffad71b 920 CONFIG_CMD_ENV_FLAGS * display details about env flags
88733e2c 921 CONFIG_CMD_ENV_EXISTS * check existence of env variable
0c79cda0 922 CONFIG_CMD_EXPORTENV * export the environment
03e2ecf6
SW
923 CONFIG_CMD_EXT2 * ext2 command support
924 CONFIG_CMD_EXT4 * ext4 command support
16f4d933
SW
925 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
926 that work for multiple fs types
bdab39d3 927 CONFIG_CMD_SAVEENV saveenv
602ad3b3 928 CONFIG_CMD_FDC * Floppy Disk Support
03e2ecf6 929 CONFIG_CMD_FAT * FAT command support
602ad3b3
JL
930 CONFIG_CMD_FDOS * Dos diskette Support
931 CONFIG_CMD_FLASH flinfo, erase, protect
932 CONFIG_CMD_FPGA FPGA device initialization support
4d98b5c8 933 CONFIG_CMD_FUSE * Device fuse support
53fdc7ef 934 CONFIG_CMD_GETTIME * Get time since boot
a641b979 935 CONFIG_CMD_GO * the 'go' command (exec code)
a000b795 936 CONFIG_CMD_GREPENV * search environment
bf36c5d5 937 CONFIG_CMD_HASH * calculate hash / digest
602ad3b3
JL
938 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
939 CONFIG_CMD_I2C * I2C serial bus support
940 CONFIG_CMD_IDE * IDE harddisk support
941 CONFIG_CMD_IMI iminfo
8fdf1e0f 942 CONFIG_CMD_IMLS List all images found in NOR flash
4d98b5c8 943 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
602ad3b3 944 CONFIG_CMD_IMMAP * IMMR dump support
0c79cda0 945 CONFIG_CMD_IMPORTENV * import an environment
c167cc02 946 CONFIG_CMD_INI * import data from an ini file into the env
602ad3b3
JL
947 CONFIG_CMD_IRQ * irqinfo
948 CONFIG_CMD_ITEST Integer/string test of 2 values
949 CONFIG_CMD_JFFS2 * JFFS2 Support
950 CONFIG_CMD_KGDB * kgdb
4d98b5c8 951 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
d22c338e
JH
952 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
953 (169.254.*.*)
602ad3b3
JL
954 CONFIG_CMD_LOADB loadb
955 CONFIG_CMD_LOADS loads
4d98b5c8 956 CONFIG_CMD_MD5SUM * print md5 message digest
02c9aa1d 957 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
15a33e49 958 CONFIG_CMD_MEMINFO * Display detailed memory information
602ad3b3 959 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
a2681707 960 loop, loopw
4d98b5c8 961 CONFIG_CMD_MEMTEST * mtest
602ad3b3
JL
962 CONFIG_CMD_MISC Misc functions like sleep etc
963 CONFIG_CMD_MMC * MMC memory mapped support
964 CONFIG_CMD_MII * MII utility commands
68d7d651 965 CONFIG_CMD_MTDPARTS * MTD partition support
602ad3b3
JL
966 CONFIG_CMD_NAND * NAND support
967 CONFIG_CMD_NET bootp, tftpboot, rarpboot
4d98b5c8 968 CONFIG_CMD_NFS NFS support
e92739d3 969 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
c0f40859 970 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
602ad3b3
JL
971 CONFIG_CMD_PCI * pciinfo
972 CONFIG_CMD_PCMCIA * PCMCIA support
973 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
974 host
975 CONFIG_CMD_PORTIO * Port I/O
ff048ea9 976 CONFIG_CMD_READ * Read raw data from partition
602ad3b3
JL
977 CONFIG_CMD_REGINFO * Register dump
978 CONFIG_CMD_RUN run command in env variable
d304931f 979 CONFIG_CMD_SANDBOX * sb command to access sandbox features
602ad3b3
JL
980 CONFIG_CMD_SAVES * save S record dump
981 CONFIG_CMD_SCSI * SCSI Support
982 CONFIG_CMD_SDRAM * print SDRAM configuration information
983 (requires CONFIG_CMD_I2C)
984 CONFIG_CMD_SETGETDCR Support for DCR Register access
985 (4xx only)
f61ec45e 986 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
4d98b5c8 987 CONFIG_CMD_SHA1SUM * print sha1 memory digest
02c9aa1d 988 (requires CONFIG_CMD_MEMORY)
7d861d95 989 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
74de7aef 990 CONFIG_CMD_SOURCE "source" command Support
602ad3b3 991 CONFIG_CMD_SPI * SPI serial bus support
7a83af07 992 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1fb7cd49 993 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
da83bcd7
JH
994 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
995 CONFIG_CMD_TIMER * access to the system tick timer
602ad3b3 996 CONFIG_CMD_USB * USB support
602ad3b3 997 CONFIG_CMD_CDP * Cisco Discover Protocol support
c8339f51 998 CONFIG_CMD_MFSL * Microblaze FSL support
4d98b5c8 999 CONFIG_CMD_XIMG Load part of Multi Image
602ad3b3 1000
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WD
1001
1002 EXAMPLE: If you want all functions except of network
1003 support you can write:
1004
602ad3b3
JL
1005 #include "config_cmd_all.h"
1006 #undef CONFIG_CMD_NET
c609719b 1007
213bf8c8
GVB
1008 Other Commands:
1009 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
c609719b
WD
1010
1011 Note: Don't enable the "icache" and "dcache" commands
602ad3b3 1012 (configuration option CONFIG_CMD_CACHE) unless you know
43d9616c
WD
1013 what you (and your U-Boot users) are doing. Data
1014 cache cannot be enabled on systems like the 8xx or
1015 8260 (where accesses to the IMMR region must be
1016 uncached), and it cannot be disabled on all other
1017 systems where we (mis-) use the data cache to hold an
1018 initial stack and some data.
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WD
1019
1020
1021 XXX - this list needs to get updated!
1022
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WD
1023- Regular expression support:
1024 CONFIG_REGEX
93e14596
WD
1025 If this variable is defined, U-Boot is linked against
1026 the SLRE (Super Light Regular Expression) library,
1027 which adds regex support to some commands, as for
1028 example "env grep" and "setexpr".
a5ecbe62 1029
45ba8077
SG
1030- Device tree:
1031 CONFIG_OF_CONTROL
1032 If this variable is defined, U-Boot will use a device tree
1033 to configure its devices, instead of relying on statically
1034 compiled #defines in the board file. This option is
1035 experimental and only available on a few boards. The device
1036 tree is available in the global data as gd->fdt_blob.
1037
2c0f79e4
SG
1038 U-Boot needs to get its device tree from somewhere. This can
1039 be done using one of the two options below:
bbb0b128
SG
1040
1041 CONFIG_OF_EMBED
1042 If this variable is defined, U-Boot will embed a device tree
1043 binary in its image. This device tree file should be in the
1044 board directory and called <soc>-<board>.dts. The binary file
1045 is then picked up in board_init_f() and made available through
1046 the global data structure as gd->blob.
45ba8077 1047
2c0f79e4
SG
1048 CONFIG_OF_SEPARATE
1049 If this variable is defined, U-Boot will build a device tree
1050 binary. It will be called u-boot.dtb. Architecture-specific
1051 code will locate it at run-time. Generally this works by:
1052
1053 cat u-boot.bin u-boot.dtb >image.bin
1054
1055 and in fact, U-Boot does this for you, creating a file called
1056 u-boot-dtb.bin which is useful in the common case. You can
1057 still use the individual files if you need something more
1058 exotic.
1059
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1060- Watchdog:
1061 CONFIG_WATCHDOG
1062 If this variable is defined, it enables watchdog
6abe6fb6
DZ
1063 support for the SoC. There must be support in the SoC
1064 specific code for a watchdog. For the 8xx and 8260
1065 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1066 register. When supported for a specific SoC is
1067 available, then no further board specific code should
1068 be needed to use it.
1069
1070 CONFIG_HW_WATCHDOG
1071 When using a watchdog circuitry external to the used
1072 SoC, then define this variable and provide board
1073 specific code for the "hw_watchdog_reset" function.
c609719b 1074
c1551ea8
SR
1075- U-Boot Version:
1076 CONFIG_VERSION_VARIABLE
1077 If this variable is defined, an environment variable
1078 named "ver" is created by U-Boot showing the U-Boot
1079 version as printed by the "version" command.
a1ea8e51
BT
1080 Any change to this variable will be reverted at the
1081 next reset.
c1551ea8 1082
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1083- Real-Time Clock:
1084
602ad3b3 1085 When CONFIG_CMD_DATE is selected, the type of the RTC
c609719b
WD
1086 has to be selected, too. Define exactly one of the
1087 following options:
1088
1089 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1090 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
4e8b7544 1091 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
c609719b 1092 CONFIG_RTC_MC146818 - use MC146818 RTC
1cb8e980 1093 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
c609719b 1094 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
7f70e853 1095 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
3bac3513 1096 CONFIG_RTC_DS164x - use Dallas DS164x RTC
9536dfcc 1097 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
4c0d4c3b 1098 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
6d0f6bcf 1099 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
71d19f30
HS
1100 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1101 RV3029 RTC.
c609719b 1102
b37c7e5e
WD
1103 Note that if the RTC uses I2C, then the I2C interface
1104 must also be configured. See I2C Support, below.
1105
e92739d3
PT
1106- GPIO Support:
1107 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
e92739d3 1108
5dec49ca
CP
1109 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1110 chip-ngpio pairs that tell the PCA953X driver the number of
1111 pins supported by a particular chip.
1112
e92739d3
PT
1113 Note that if the GPIO device uses I2C, then the I2C interface
1114 must also be configured. See I2C Support, below.
1115
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WD
1116- Timestamp Support:
1117
43d9616c
WD
1118 When CONFIG_TIMESTAMP is selected, the timestamp
1119 (date and time) of an image is printed by image
1120 commands like bootm or iminfo. This option is
602ad3b3 1121 automatically enabled when you select CONFIG_CMD_DATE .
c609719b 1122
923c46f9
KP
1123- Partition Labels (disklabels) Supported:
1124 Zero or more of the following:
1125 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1126 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1127 Intel architecture, USB sticks, etc.
1128 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1129 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1130 bootloader. Note 2TB partition limit; see
1131 disk/part_efi.c
1132 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
c609719b 1133
218ca724
WD
1134 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1135 CONFIG_CMD_SCSI) you must configure support for at
923c46f9 1136 least one non-MTD partition type as well.
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WD
1137
1138- IDE Reset method:
4d13cbad
WD
1139 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1140 board configurations files but used nowhere!
c609719b 1141
4d13cbad
WD
1142 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1143 be performed by calling the function
1144 ide_set_reset(int reset)
1145 which has to be defined in a board specific file
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WD
1146
1147- ATAPI Support:
1148 CONFIG_ATAPI
1149
1150 Set this to enable ATAPI support.
1151
c40b2956
WD
1152- LBA48 Support
1153 CONFIG_LBA48
1154
1155 Set this to enable support for disks larger than 137GB
4b142feb 1156 Also look at CONFIG_SYS_64BIT_LBA.
c40b2956
WD
1157 Whithout these , LBA48 support uses 32bit variables and will 'only'
1158 support disks up to 2.1TB.
1159
6d0f6bcf 1160 CONFIG_SYS_64BIT_LBA:
c40b2956
WD
1161 When enabled, makes the IDE subsystem use 64bit sector addresses.
1162 Default is 32bit.
1163
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WD
1164- SCSI Support:
1165 At the moment only there is only support for the
1166 SYM53C8XX SCSI controller; define
1167 CONFIG_SCSI_SYM53C8XX to enable it.
1168
6d0f6bcf
JCPV
1169 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1170 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1171 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
c609719b
WD
1172 maximum numbers of LUNs, SCSI ID's and target
1173 devices.
6d0f6bcf 1174 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
c609719b 1175
93e14596
WD
1176 The environment variable 'scsidevs' is set to the number of
1177 SCSI devices found during the last scan.
447c031b 1178
c609719b 1179- NETWORK Support (PCI):
682011ff 1180 CONFIG_E1000
ce5207e1
KM
1181 Support for Intel 8254x/8257x gigabit chips.
1182
1183 CONFIG_E1000_SPI
1184 Utility code for direct access to the SPI bus on Intel 8257x.
1185 This does not do anything useful unless you set at least one
1186 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1187
1188 CONFIG_E1000_SPI_GENERIC
1189 Allow generic access to the SPI bus on the Intel 8257x, for
1190 example with the "sspi" command.
1191
1192 CONFIG_CMD_E1000
1193 Management command for E1000 devices. When used on devices
1194 with SPI support you can reprogram the EEPROM from U-Boot.
53cf9435 1195
ac3315c2 1196 CONFIG_E1000_FALLBACK_MAC
11ccc33f 1197 default MAC for empty EEPROM after production.
ac3315c2 1198
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WD
1199 CONFIG_EEPRO100
1200 Support for Intel 82557/82559/82559ER chips.
11ccc33f 1201 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
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WD
1202 write routine for first time initialisation.
1203
1204 CONFIG_TULIP
1205 Support for Digital 2114x chips.
1206 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1207 modem chip initialisation (KS8761/QS6611).
1208
1209 CONFIG_NATSEMI
1210 Support for National dp83815 chips.
1211
1212 CONFIG_NS8382X
1213 Support for National dp8382[01] gigabit chips.
1214
45219c46
WD
1215- NETWORK Support (other):
1216
c041e9d2
JS
1217 CONFIG_DRIVER_AT91EMAC
1218 Support for AT91RM9200 EMAC.
1219
1220 CONFIG_RMII
1221 Define this to use reduced MII inteface
1222
1223 CONFIG_DRIVER_AT91EMAC_QUIET
1224 If this defined, the driver is quiet.
1225 The driver doen't show link status messages.
1226
efdd7319
RH
1227 CONFIG_CALXEDA_XGMAC
1228 Support for the Calxeda XGMAC device
1229
3bb46d23 1230 CONFIG_LAN91C96
45219c46
WD
1231 Support for SMSC's LAN91C96 chips.
1232
1233 CONFIG_LAN91C96_BASE
1234 Define this to hold the physical address
1235 of the LAN91C96's I/O space
1236
1237 CONFIG_LAN91C96_USE_32_BIT
1238 Define this to enable 32 bit addressing
1239
3bb46d23 1240 CONFIG_SMC91111
f39748ae
WD
1241 Support for SMSC's LAN91C111 chip
1242
1243 CONFIG_SMC91111_BASE
1244 Define this to hold the physical address
1245 of the device (I/O space)
1246
1247 CONFIG_SMC_USE_32_BIT
1248 Define this if data bus is 32 bits
1249
1250 CONFIG_SMC_USE_IOFUNCS
1251 Define this to use i/o functions instead of macros
1252 (some hardware wont work with macros)
1253
dc02bada
HS
1254 CONFIG_DRIVER_TI_EMAC
1255 Support for davinci emac
1256
1257 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1258 Define this if you have more then 3 PHYs.
1259
b3dbf4a5
ML
1260 CONFIG_FTGMAC100
1261 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1262
1263 CONFIG_FTGMAC100_EGIGA
1264 Define this to use GE link update with gigabit PHY.
1265 Define this if FTGMAC100 is connected to gigabit PHY.
1266 If your system has 10/100 PHY only, it might not occur
1267 wrong behavior. Because PHY usually return timeout or
1268 useless data when polling gigabit status and gigabit
1269 control registers. This behavior won't affect the
1270 correctnessof 10/100 link speed update.
1271
c2fff331 1272 CONFIG_SMC911X
557b377d
JG
1273 Support for SMSC's LAN911x and LAN921x chips
1274
c2fff331 1275 CONFIG_SMC911X_BASE
557b377d
JG
1276 Define this to hold the physical address
1277 of the device (I/O space)
1278
c2fff331 1279 CONFIG_SMC911X_32_BIT
557b377d
JG
1280 Define this if data bus is 32 bits
1281
c2fff331 1282 CONFIG_SMC911X_16_BIT
557b377d
JG
1283 Define this if data bus is 16 bits. If your processor
1284 automatically converts one 32 bit word to two 16 bit
c2fff331 1285 words you may also try CONFIG_SMC911X_32_BIT.
557b377d 1286
3d0075fa
YS
1287 CONFIG_SH_ETHER
1288 Support for Renesas on-chip Ethernet controller
1289
1290 CONFIG_SH_ETHER_USE_PORT
1291 Define the number of ports to be used
1292
1293 CONFIG_SH_ETHER_PHY_ADDR
1294 Define the ETH PHY's address
1295
68260aab
YS
1296 CONFIG_SH_ETHER_CACHE_WRITEBACK
1297 If this option is set, the driver enables cache flush.
1298
5e124724 1299- TPM Support:
90899cc0
CC
1300 CONFIG_TPM
1301 Support TPM devices.
1302
1b393db5
TWHT
1303 CONFIG_TPM_TIS_I2C
1304 Support for i2c bus TPM devices. Only one device
1305 per system is supported at this time.
1306
1307 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1308 Define the the i2c bus number for the TPM device
1309
1310 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1311 Define the TPM's address on the i2c bus
1312
1313 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1314 Define the burst count bytes upper limit
1315
c01939c7
DE
1316 CONFIG_TPM_ATMEL_TWI
1317 Support for Atmel TWI TPM device. Requires I2C support.
1318
90899cc0 1319 CONFIG_TPM_TIS_LPC
5e124724
VB
1320 Support for generic parallel port TPM devices. Only one device
1321 per system is supported at this time.
1322
1323 CONFIG_TPM_TIS_BASE_ADDRESS
1324 Base address where the generic TPM device is mapped
1325 to. Contemporary x86 systems usually map it at
1326 0xfed40000.
1327
be6c1529
RP
1328 CONFIG_CMD_TPM
1329 Add tpm monitor functions.
1330 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1331 provides monitor access to authorized functions.
1332
1333 CONFIG_TPM
1334 Define this to enable the TPM support library which provides
1335 functional interfaces to some TPM commands.
1336 Requires support for a TPM device.
1337
1338 CONFIG_TPM_AUTH_SESSIONS
1339 Define this to enable authorized functions in the TPM library.
1340 Requires CONFIG_TPM and CONFIG_SHA1.
1341
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WD
1342- USB Support:
1343 At the moment only the UHCI host controller is
4d13cbad 1344 supported (PIP405, MIP405, MPC5200); define
c609719b
WD
1345 CONFIG_USB_UHCI to enable it.
1346 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
30d56fae 1347 and define CONFIG_USB_STORAGE to enable the USB
c609719b
WD
1348 storage devices.
1349 Note:
1350 Supported are USB Keyboards and USB Floppy drives
1351 (TEAC FD-05PUB).
4d13cbad
WD
1352 MPC5200 USB requires additional defines:
1353 CONFIG_USB_CLOCK
1354 for 528 MHz Clock: 0x0001bbbb
307ecb6d
EM
1355 CONFIG_PSC3_USB
1356 for USB on PSC3
4d13cbad
WD
1357 CONFIG_USB_CONFIG
1358 for differential drivers: 0x00001000
1359 for single ended drivers: 0x00005000
307ecb6d
EM
1360 for differential drivers on PSC3: 0x00000100
1361 for single ended drivers on PSC3: 0x00004100
6d0f6bcf 1362 CONFIG_SYS_USB_EVENT_POLL
fdcfaa1b
ZW
1363 May be defined to allow interrupt polling
1364 instead of using asynchronous interrupts
4d13cbad 1365
9ab4ce22
SG
1366 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1367 txfilltuning field in the EHCI controller on reset.
1368
aa155058
KJS
1369 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1370 interval for usb hub power-on delay.(minimum 100msec)
1371
16c8d5e7
WD
1372- USB Device:
1373 Define the below if you wish to use the USB console.
1374 Once firmware is rebuilt from a serial console issue the
1375 command "setenv stdin usbtty; setenv stdout usbtty" and
11ccc33f 1376 attach your USB cable. The Unix command "dmesg" should print
16c8d5e7
WD
1377 it has found a new device. The environment variable usbtty
1378 can be set to gserial or cdc_acm to enable your device to
386eda02 1379 appear to a USB host as a Linux gserial device or a
16c8d5e7
WD
1380 Common Device Class Abstract Control Model serial device.
1381 If you select usbtty = gserial you should be able to enumerate
1382 a Linux host by
1383 # modprobe usbserial vendor=0xVendorID product=0xProductID
1384 else if using cdc_acm, simply setting the environment
1385 variable usbtty to be cdc_acm should suffice. The following
1386 might be defined in YourBoardName.h
386eda02 1387
16c8d5e7
WD
1388 CONFIG_USB_DEVICE
1389 Define this to build a UDC device
1390
1391 CONFIG_USB_TTY
1392 Define this to have a tty type of device available to
1393 talk to the UDC device
386eda02 1394
f9da0f89
VK
1395 CONFIG_USBD_HS
1396 Define this to enable the high speed support for usb
1397 device and usbtty. If this feature is enabled, a routine
1398 int is_usbd_high_speed(void)
1399 also needs to be defined by the driver to dynamically poll
1400 whether the enumeration has succeded at high speed or full
1401 speed.
1402
6d0f6bcf 1403 CONFIG_SYS_CONSOLE_IS_IN_ENV
16c8d5e7
WD
1404 Define this if you want stdin, stdout &/or stderr to
1405 be set to usbtty.
1406
1407 mpc8xx:
6d0f6bcf 1408 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
16c8d5e7 1409 Derive USB clock from external clock "blah"
6d0f6bcf 1410 - CONFIG_SYS_USB_EXTC_CLK 0x02
386eda02 1411
6d0f6bcf 1412 CONFIG_SYS_USB_BRG_CLK 0xBLAH
16c8d5e7 1413 Derive USB clock from brgclk
6d0f6bcf 1414 - CONFIG_SYS_USB_BRG_CLK 0x04
16c8d5e7 1415
386eda02 1416 If you have a USB-IF assigned VendorID then you may wish to
16c8d5e7 1417 define your own vendor specific values either in BoardName.h
386eda02 1418 or directly in usbd_vendor_info.h. If you don't define
16c8d5e7
WD
1419 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1420 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1421 should pretend to be a Linux device to it's target host.
1422
1423 CONFIG_USBD_MANUFACTURER
1424 Define this string as the name of your company for
1425 - CONFIG_USBD_MANUFACTURER "my company"
386eda02 1426
16c8d5e7
WD
1427 CONFIG_USBD_PRODUCT_NAME
1428 Define this string as the name of your product
1429 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1430
1431 CONFIG_USBD_VENDORID
1432 Define this as your assigned Vendor ID from the USB
1433 Implementors Forum. This *must* be a genuine Vendor ID
1434 to avoid polluting the USB namespace.
1435 - CONFIG_USBD_VENDORID 0xFFFF
386eda02 1436
16c8d5e7
WD
1437 CONFIG_USBD_PRODUCTID
1438 Define this as the unique Product ID
1439 for your device
1440 - CONFIG_USBD_PRODUCTID 0xFFFF
4d13cbad 1441
351e9b20
PM
1442 Some USB device drivers may need to check USB cable attachment.
1443 In this case you can enable following config in BoardName.h:
1444 CONFIG_USB_CABLE_CHECK
1445 This enables function definition:
1446 - usb_cable_connected() in include/usb.h
1447 Implementation of this function is board-specific.
1448
d70a560f
IG
1449- ULPI Layer Support:
1450 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1451 the generic ULPI layer. The generic layer accesses the ULPI PHY
1452 via the platform viewport, so you need both the genric layer and
1453 the viewport enabled. Currently only Chipidea/ARC based
1454 viewport is supported.
1455 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1456 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
6d365ea0
LS
1457 If your ULPI phy needs a different reference clock than the
1458 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1459 the appropriate value in Hz.
c609719b 1460
71f95118 1461- MMC Support:
8bde7f77
WD
1462 The MMC controller on the Intel PXA is supported. To
1463 enable this define CONFIG_MMC. The MMC can be
1464 accessed from the boot prompt by mapping the device
71f95118 1465 to physical memory similar to flash. Command line is
602ad3b3
JL
1466 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1467 the FAT fs. This is enabled with CONFIG_CMD_FAT.
71f95118 1468
afb35666
YS
1469 CONFIG_SH_MMCIF
1470 Support for Renesas on-chip MMCIF controller
1471
1472 CONFIG_SH_MMCIF_ADDR
1473 Define the base address of MMCIF registers
1474
1475 CONFIG_SH_MMCIF_CLK
1476 Define the clock frequency for MMCIF
1477
b3ba6e94
TR
1478- USB Device Firmware Update (DFU) class support:
1479 CONFIG_DFU_FUNCTION
1480 This enables the USB portion of the DFU USB class
1481
1482 CONFIG_CMD_DFU
1483 This enables the command "dfu" which is used to have
1484 U-Boot create a DFU class device via USB. This command
1485 requires that the "dfu_alt_info" environment variable be
1486 set and define the alt settings to expose to the host.
1487
1488 CONFIG_DFU_MMC
1489 This enables support for exposing (e)MMC devices via DFU.
1490
c6631764
PA
1491 CONFIG_DFU_NAND
1492 This enables support for exposing NAND devices via DFU.
1493
a9479f04
AM
1494 CONFIG_DFU_RAM
1495 This enables support for exposing RAM via DFU.
1496 Note: DFU spec refer to non-volatile memory usage, but
1497 allow usages beyond the scope of spec - here RAM usage,
1498 one that would help mostly the developer.
1499
e7e75c70
HS
1500 CONFIG_SYS_DFU_DATA_BUF_SIZE
1501 Dfu transfer uses a buffer before writing data to the
1502 raw storage device. Make the size (in bytes) of this buffer
1503 configurable. The size of this buffer is also configurable
1504 through the "dfu_bufsiz" environment variable.
1505
ea2453d5
PA
1506 CONFIG_SYS_DFU_MAX_FILE_SIZE
1507 When updating files rather than the raw storage device,
1508 we use a static buffer to copy the file into and then write
1509 the buffer once we've been given the whole file. Define
1510 this to the maximum filesize (in bytes) for the buffer.
1511 Default is 4 MiB if undefined.
1512
6705d81e
WD
1513- Journaling Flash filesystem support:
1514 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1515 CONFIG_JFFS2_NAND_DEV
1516 Define these for a default partition on a NAND device
1517
6d0f6bcf
JCPV
1518 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1519 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
6705d81e
WD
1520 Define these for a default partition on a NOR device
1521
6d0f6bcf 1522 CONFIG_SYS_JFFS_CUSTOM_PART
6705d81e
WD
1523 Define this to create an own partition. You have to provide a
1524 function struct part_info* jffs2_part_info(int part_num)
1525
1526 If you define only one JFFS2 partition you may also want to
6d0f6bcf 1527 #define CONFIG_SYS_JFFS_SINGLE_PART 1
6705d81e
WD
1528 to disable the command chpart. This is the default when you
1529 have not defined a custom partition
1530
c30a15e5
DK
1531- FAT(File Allocation Table) filesystem write function support:
1532 CONFIG_FAT_WRITE
656f4c65
DK
1533
1534 Define this to enable support for saving memory data as a
1535 file in FAT formatted partition.
1536
1537 This will also enable the command "fatwrite" enabling the
1538 user to write files to FAT.
c30a15e5 1539
84cd9327
GB
1540CBFS (Coreboot Filesystem) support
1541 CONFIG_CMD_CBFS
1542
1543 Define this to enable support for reading from a Coreboot
1544 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1545 and cbfsload.
1546
c609719b
WD
1547- Keyboard Support:
1548 CONFIG_ISA_KEYBOARD
1549
1550 Define this to enable standard (PC-Style) keyboard
1551 support
1552
1553 CONFIG_I8042_KBD
1554 Standard PC keyboard driver with US (is default) and
1555 GERMAN key layout (switch via environment 'keymap=de') support.
1556 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1557 for cfb_console. Supports cursor blinking.
1558
713cb680
HT
1559 CONFIG_CROS_EC_KEYB
1560 Enables a Chrome OS keyboard using the CROS_EC interface.
1561 This uses CROS_EC to communicate with a second microcontroller
1562 which provides key scans on request.
1563
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WD
1564- Video support:
1565 CONFIG_VIDEO
1566
1567 Define this to enable video support (for output to
1568 video).
1569
1570 CONFIG_VIDEO_CT69000
1571
1572 Enable Chips & Technologies 69000 Video chip
1573
1574 CONFIG_VIDEO_SMI_LYNXEM
b79a11cc 1575 Enable Silicon Motion SMI 712/710/810 Video chip. The
eeb1b77b
WD
1576 video output is selected via environment 'videoout'
1577 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1578 assumed.
1579
b79a11cc 1580 For the CT69000 and SMI_LYNXEM drivers, videomode is
11ccc33f 1581 selected via environment 'videomode'. Two different ways
eeb1b77b
WD
1582 are possible:
1583 - "videomode=num" 'num' is a standard LiLo mode numbers.
6e592385 1584 Following standard modes are supported (* is default):
eeb1b77b
WD
1585
1586 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1587 -------------+---------------------------------------------
1588 8 bits | 0x301* 0x303 0x305 0x161 0x307
1589 15 bits | 0x310 0x313 0x316 0x162 0x319
1590 16 bits | 0x311 0x314 0x317 0x163 0x31A
1591 24 bits | 0x312 0x315 0x318 ? 0x31B
1592 -------------+---------------------------------------------
c609719b
WD
1593 (i.e. setenv videomode 317; saveenv; reset;)
1594
b79a11cc 1595 - "videomode=bootargs" all the video parameters are parsed
7817cb20 1596 from the bootargs. (See drivers/video/videomodes.c)
eeb1b77b
WD
1597
1598
c1551ea8 1599 CONFIG_VIDEO_SED13806
43d9616c 1600 Enable Epson SED13806 driver. This driver supports 8bpp
a6c7ad2f
WD
1601 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1602 or CONFIG_VIDEO_SED13806_16BPP
1603
7d3053fb 1604 CONFIG_FSL_DIU_FB
04e5ae79 1605 Enable the Freescale DIU video driver. Reference boards for
7d3053fb
TT
1606 SOCs that have a DIU should define this macro to enable DIU
1607 support, and should also define these other macros:
1608
1609 CONFIG_SYS_DIU_ADDR
1610 CONFIG_VIDEO
1611 CONFIG_CMD_BMP
1612 CONFIG_CFB_CONSOLE
1613 CONFIG_VIDEO_SW_CURSOR
1614 CONFIG_VGA_AS_SINGLE_DEVICE
1615 CONFIG_VIDEO_LOGO
1616 CONFIG_VIDEO_BMP_LOGO
1617
ba8e76bd
TT
1618 The DIU driver will look for the 'video-mode' environment
1619 variable, and if defined, enable the DIU as a console during
1620 boot. See the documentation file README.video for a
1621 description of this variable.
7d3053fb 1622
058d59b0
SG
1623 CONFIG_VIDEO_VGA
1624
1625 Enable the VGA video / BIOS for x86. The alternative if you
1626 are using coreboot is to use the coreboot frame buffer
1627 driver.
1628
1629
682011ff 1630- Keyboard Support:
8bde7f77 1631 CONFIG_KEYBOARD
682011ff 1632
8bde7f77
WD
1633 Define this to enable a custom keyboard support.
1634 This simply calls drv_keyboard_init() which must be
1635 defined in your board-specific files.
1636 The only board using this so far is RBC823.
a6c7ad2f 1637
c609719b
WD
1638- LCD Support: CONFIG_LCD
1639
1640 Define this to enable LCD support (for output to LCD
1641 display); also select one of the supported displays
1642 by defining one of these:
1643
39cf4804
SP
1644 CONFIG_ATMEL_LCD:
1645
1646 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1647
fd3103bb 1648 CONFIG_NEC_NL6448AC33:
c609719b 1649
fd3103bb 1650 NEC NL6448AC33-18. Active, color, single scan.
c609719b 1651
fd3103bb 1652 CONFIG_NEC_NL6448BC20
c609719b 1653
fd3103bb
WD
1654 NEC NL6448BC20-08. 6.5", 640x480.
1655 Active, color, single scan.
1656
1657 CONFIG_NEC_NL6448BC33_54
1658
1659 NEC NL6448BC33-54. 10.4", 640x480.
c609719b
WD
1660 Active, color, single scan.
1661
1662 CONFIG_SHARP_16x9
1663
1664 Sharp 320x240. Active, color, single scan.
1665 It isn't 16x9, and I am not sure what it is.
1666
1667 CONFIG_SHARP_LQ64D341
1668
1669 Sharp LQ64D341 display, 640x480.
1670 Active, color, single scan.
1671
1672 CONFIG_HLD1045
1673
1674 HLD1045 display, 640x480.
1675 Active, color, single scan.
1676
1677 CONFIG_OPTREX_BW
1678
1679 Optrex CBL50840-2 NF-FW 99 22 M5
1680 or
1681 Hitachi LMG6912RPFC-00T
1682 or
1683 Hitachi SP14Q002
1684
1685 320x240. Black & white.
1686
1687 Normally display is black on white background; define
6d0f6bcf 1688 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
c609719b 1689
676d319e
SG
1690 CONFIG_LCD_ALIGNMENT
1691
1692 Normally the LCD is page-aligned (tyically 4KB). If this is
1693 defined then the LCD will be aligned to this value instead.
1694 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1695 here, since it is cheaper to change data cache settings on
1696 a per-section basis.
1697
0d89efef
SG
1698 CONFIG_CONSOLE_SCROLL_LINES
1699
1700 When the console need to be scrolled, this is the number of
1701 lines to scroll by. It defaults to 1. Increasing this makes
1702 the console jump but can help speed up operation when scrolling
1703 is slow.
676d319e 1704
45d7f525
TWHT
1705 CONFIG_LCD_BMP_RLE8
1706
1707 Support drawing of RLE8-compressed bitmaps on the LCD.
1708
735987c5
TWHT
1709 CONFIG_I2C_EDID
1710
1711 Enables an 'i2c edid' command which can read EDID
1712 information over I2C from an attached LCD display.
1713
7152b1d0 1714- Splash Screen Support: CONFIG_SPLASH_SCREEN
d791b1dc 1715
8bde7f77
WD
1716 If this option is set, the environment is checked for
1717 a variable "splashimage". If found, the usual display
1718 of logo, copyright and system information on the LCD
e94d2cd9 1719 is suppressed and the BMP image at the address
8bde7f77
WD
1720 specified in "splashimage" is loaded instead. The
1721 console is redirected to the "nulldev", too. This
1722 allows for a "silent" boot where a splash screen is
1723 loaded very quickly after power-on.
d791b1dc 1724
c0880485
NK
1725 CONFIG_SPLASHIMAGE_GUARD
1726
1727 If this option is set, then U-Boot will prevent the environment
1728 variable "splashimage" from being set to a problematic address
1729 (see README.displaying-bmps and README.arm-unaligned-accesses).
1730 This option is useful for targets where, due to alignment
1731 restrictions, an improperly aligned BMP image will cause a data
1732 abort. If you think you will not have problems with unaligned
1733 accesses (for example because your toolchain prevents them)
1734 there is no need to set this option.
1735
1ca298ce
MW
1736 CONFIG_SPLASH_SCREEN_ALIGN
1737
1738 If this option is set the splash image can be freely positioned
1739 on the screen. Environment variable "splashpos" specifies the
1740 position as "x,y". If a positive number is given it is used as
1741 number of pixel from left/top. If a negative number is given it
1742 is used as number of pixel from right/bottom. You can also
1743 specify 'm' for centering the image.
1744
1745 Example:
1746 setenv splashpos m,m
1747 => image at center of screen
1748
1749 setenv splashpos 30,20
1750 => image at x = 30 and y = 20
1751
1752 setenv splashpos -10,m
1753 => vertically centered image
1754 at x = dspWidth - bmpWidth - 9
1755
98f4a3df
SR
1756- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1757
1758 If this option is set, additionally to standard BMP
1759 images, gzipped BMP images can be displayed via the
1760 splashscreen support or the bmp command.
1761
d5011762
AG
1762- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1763
1764 If this option is set, 8-bit RLE compressed BMP images
1765 can be displayed via the splashscreen support or the
1766 bmp command.
1767
f2b96dfb
LW
1768- Do compresssing for memory range:
1769 CONFIG_CMD_ZIP
1770
1771 If this option is set, it would use zlib deflate method
1772 to compress the specified memory at its best effort.
1773
c29fdfc1 1774- Compression support:
8ef70478
KC
1775 CONFIG_GZIP
1776
1777 Enabled by default to support gzip compressed images.
1778
c29fdfc1
WD
1779 CONFIG_BZIP2
1780
1781 If this option is set, support for bzip2 compressed
1782 images is included. If not, only uncompressed and gzip
1783 compressed images are supported.
1784
42d1f039 1785 NOTE: the bzip2 algorithm requires a lot of RAM, so
6d0f6bcf 1786 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
42d1f039 1787 be at least 4MB.
d791b1dc 1788
fc9c1727
LCM
1789 CONFIG_LZMA
1790
1791 If this option is set, support for lzma compressed
1792 images is included.
1793
1794 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1795 requires an amount of dynamic memory that is given by the
1796 formula:
1797
1798 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1799
1800 Where lc and lp stand for, respectively, Literal context bits
1801 and Literal pos bits.
1802
1803 This value is upper-bounded by 14MB in the worst case. Anyway,
1804 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1805 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1806 a very small buffer.
1807
1808 Use the lzmainfo tool to determinate the lc and lp values and
1809 then calculate the amount of needed dynamic memory (ensuring
6d0f6bcf 1810 the appropriate CONFIG_SYS_MALLOC_LEN value).
fc9c1727 1811
8ef70478
KC
1812 CONFIG_LZO
1813
1814 If this option is set, support for LZO compressed images
1815 is included.
1816
17ea1177
WD
1817- MII/PHY support:
1818 CONFIG_PHY_ADDR
1819
1820 The address of PHY on MII bus.
1821
1822 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1823
1824 The clock frequency of the MII bus
1825
1826 CONFIG_PHY_GIGE
1827
1828 If this option is set, support for speed/duplex
11ccc33f 1829 detection of gigabit PHY is included.
17ea1177
WD
1830
1831 CONFIG_PHY_RESET_DELAY
1832
1833 Some PHY like Intel LXT971A need extra delay after
1834 reset before any MII register access is possible.
1835 For such PHY, set this option to the usec delay
1836 required. (minimum 300usec for LXT971A)
1837
1838 CONFIG_PHY_CMD_DELAY (ppc4xx)
1839
1840 Some PHY like Intel LXT971A need extra delay after
1841 command issued before MII status register can be read
1842
c609719b
WD
1843- Ethernet address:
1844 CONFIG_ETHADDR
c68a05fe 1845 CONFIG_ETH1ADDR
c609719b
WD
1846 CONFIG_ETH2ADDR
1847 CONFIG_ETH3ADDR
c68a05fe 1848 CONFIG_ETH4ADDR
1849 CONFIG_ETH5ADDR
c609719b 1850
11ccc33f
MZ
1851 Define a default value for Ethernet address to use
1852 for the respective Ethernet interface, in case this
c609719b
WD
1853 is not determined automatically.
1854
1855- IP address:
1856 CONFIG_IPADDR
1857
1858 Define a default value for the IP address to use for
11ccc33f 1859 the default Ethernet interface, in case this is not
c609719b 1860 determined through e.g. bootp.
1ebcd654 1861 (Environment variable "ipaddr")
c609719b
WD
1862
1863- Server IP address:
1864 CONFIG_SERVERIP
1865
11ccc33f 1866 Defines a default value for the IP address of a TFTP
c609719b 1867 server to contact when using the "tftboot" command.
1ebcd654 1868 (Environment variable "serverip")
c609719b 1869
97cfe861
RG
1870 CONFIG_KEEP_SERVERADDR
1871
1872 Keeps the server's MAC address, in the env 'serveraddr'
1873 for passing to bootargs (like Linux's netconsole option)
1874
1ebcd654
WD
1875- Gateway IP address:
1876 CONFIG_GATEWAYIP
1877
1878 Defines a default value for the IP address of the
1879 default router where packets to other networks are
1880 sent to.
1881 (Environment variable "gatewayip")
1882
1883- Subnet mask:
1884 CONFIG_NETMASK
1885
1886 Defines a default value for the subnet mask (or
1887 routing prefix) which is used to determine if an IP
1888 address belongs to the local subnet or needs to be
1889 forwarded through a router.
1890 (Environment variable "netmask")
1891
53a5c424
DU
1892- Multicast TFTP Mode:
1893 CONFIG_MCAST_TFTP
1894
1895 Defines whether you want to support multicast TFTP as per
1896 rfc-2090; for example to work with atftp. Lets lots of targets
11ccc33f 1897 tftp down the same boot image concurrently. Note: the Ethernet
53a5c424
DU
1898 driver in use must provide a function: mcast() to join/leave a
1899 multicast group.
1900
c609719b
WD
1901- BOOTP Recovery Mode:
1902 CONFIG_BOOTP_RANDOM_DELAY
1903
1904 If you have many targets in a network that try to
1905 boot using BOOTP, you may want to avoid that all
1906 systems send out BOOTP requests at precisely the same
1907 moment (which would happen for instance at recovery
1908 from a power failure, when all systems will try to
1909 boot, thus flooding the BOOTP server. Defining
1910 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1911 inserted before sending out BOOTP requests. The
6c33c785 1912 following delays are inserted then:
c609719b
WD
1913
1914 1st BOOTP request: delay 0 ... 1 sec
1915 2nd BOOTP request: delay 0 ... 2 sec
1916 3rd BOOTP request: delay 0 ... 4 sec
1917 4th and following
1918 BOOTP requests: delay 0 ... 8 sec
1919
fe389a82 1920- DHCP Advanced Options:
1fe80d79
JL
1921 You can fine tune the DHCP functionality by defining
1922 CONFIG_BOOTP_* symbols:
1923
1924 CONFIG_BOOTP_SUBNETMASK
1925 CONFIG_BOOTP_GATEWAY
1926 CONFIG_BOOTP_HOSTNAME
1927 CONFIG_BOOTP_NISDOMAIN
1928 CONFIG_BOOTP_BOOTPATH
1929 CONFIG_BOOTP_BOOTFILESIZE
1930 CONFIG_BOOTP_DNS
1931 CONFIG_BOOTP_DNS2
1932 CONFIG_BOOTP_SEND_HOSTNAME
1933 CONFIG_BOOTP_NTPSERVER
1934 CONFIG_BOOTP_TIMEOFFSET
1935 CONFIG_BOOTP_VENDOREX
2c00e099 1936 CONFIG_BOOTP_MAY_FAIL
fe389a82 1937
5d110f0a
WC
1938 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1939 environment variable, not the BOOTP server.
fe389a82 1940
2c00e099
JH
1941 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1942 after the configured retry count, the call will fail
1943 instead of starting over. This can be used to fail over
1944 to Link-local IP address configuration if the DHCP server
1945 is not available.
1946
fe389a82
SR
1947 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1948 serverip from a DHCP server, it is possible that more
1949 than one DNS serverip is offered to the client.
1950 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1951 serverip will be stored in the additional environment
1952 variable "dnsip2". The first DNS serverip is always
1953 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1fe80d79 1954 is defined.
fe389a82
SR
1955
1956 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1957 to do a dynamic update of a DNS server. To do this, they
1958 need the hostname of the DHCP requester.
5d110f0a 1959 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1fe80d79
JL
1960 of the "hostname" environment variable is passed as
1961 option 12 to the DHCP server.
fe389a82 1962
d9a2f416
AV
1963 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1964
1965 A 32bit value in microseconds for a delay between
1966 receiving a "DHCP Offer" and sending the "DHCP Request".
1967 This fixes a problem with certain DHCP servers that don't
1968 respond 100% of the time to a "DHCP request". E.g. On an
1969 AT91RM9200 processor running at 180MHz, this delay needed
1970 to be *at least* 15,000 usec before a Windows Server 2003
1971 DHCP server would reply 100% of the time. I recommend at
1972 least 50,000 usec to be safe. The alternative is to hope
1973 that one of the retries will be successful but note that
1974 the DHCP timeout and retry process takes a longer than
1975 this delay.
1976
d22c338e
JH
1977 - Link-local IP address negotiation:
1978 Negotiate with other link-local clients on the local network
1979 for an address that doesn't require explicit configuration.
1980 This is especially useful if a DHCP server cannot be guaranteed
1981 to exist in all environments that the device must operate.
1982
1983 See doc/README.link-local for more information.
1984
a3d991bd 1985 - CDP Options:
6e592385 1986 CONFIG_CDP_DEVICE_ID
a3d991bd
WD
1987
1988 The device id used in CDP trigger frames.
1989
1990 CONFIG_CDP_DEVICE_ID_PREFIX
1991
1992 A two character string which is prefixed to the MAC address
1993 of the device.
1994
1995 CONFIG_CDP_PORT_ID
1996
1997 A printf format string which contains the ascii name of
1998 the port. Normally is set to "eth%d" which sets
11ccc33f 1999 eth0 for the first Ethernet, eth1 for the second etc.
a3d991bd
WD
2000
2001 CONFIG_CDP_CAPABILITIES
2002
2003 A 32bit integer which indicates the device capabilities;
2004 0x00000010 for a normal host which does not forwards.
2005
2006 CONFIG_CDP_VERSION
2007
2008 An ascii string containing the version of the software.
2009
2010 CONFIG_CDP_PLATFORM
2011
2012 An ascii string containing the name of the platform.
2013
2014 CONFIG_CDP_TRIGGER
2015
2016 A 32bit integer sent on the trigger.
2017
2018 CONFIG_CDP_POWER_CONSUMPTION
2019
2020 A 16bit integer containing the power consumption of the
2021 device in .1 of milliwatts.
2022
2023 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2024
2025 A byte containing the id of the VLAN.
2026
c609719b
WD
2027- Status LED: CONFIG_STATUS_LED
2028
2029 Several configurations allow to display the current
2030 status using a LED. For instance, the LED will blink
2031 fast while running U-Boot code, stop blinking as
2032 soon as a reply to a BOOTP request was received, and
2033 start blinking slow once the Linux kernel is running
2034 (supported by a status LED driver in the Linux
2035 kernel). Defining CONFIG_STATUS_LED enables this
2036 feature in U-Boot.
2037
1df7bbba
IG
2038 Additional options:
2039
2040 CONFIG_GPIO_LED
2041 The status LED can be connected to a GPIO pin.
2042 In such cases, the gpio_led driver can be used as a
2043 status LED backend implementation. Define CONFIG_GPIO_LED
2044 to include the gpio_led driver in the U-Boot binary.
2045
9dfdcdfe
IG
2046 CONFIG_GPIO_LED_INVERTED_TABLE
2047 Some GPIO connected LEDs may have inverted polarity in which
2048 case the GPIO high value corresponds to LED off state and
2049 GPIO low value corresponds to LED on state.
2050 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2051 with a list of GPIO LEDs that have inverted polarity.
2052
c609719b
WD
2053- CAN Support: CONFIG_CAN_DRIVER
2054
2055 Defining CONFIG_CAN_DRIVER enables CAN driver support
2056 on those systems that support this (optional)
2057 feature, like the TQM8xxL modules.
2058
3f4978c7
HS
2059- I2C Support: CONFIG_SYS_I2C
2060
2061 This enable the NEW i2c subsystem, and will allow you to use
2062 i2c commands at the u-boot command line (as long as you set
2063 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2064 based realtime clock chips or other i2c devices. See
2065 common/cmd_i2c.c for a description of the command line
2066 interface.
2067
2068 ported i2c driver to the new framework:
ea818dbb
HS
2069 - drivers/i2c/soft_i2c.c:
2070 - activate first bus with CONFIG_SYS_I2C_SOFT define
2071 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2072 for defining speed and slave address
2073 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2074 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2075 for defining speed and slave address
2076 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2077 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2078 for defining speed and slave address
2079 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2080 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2081 for defining speed and slave address
3f4978c7 2082
00f792e0
HS
2083 - drivers/i2c/fsl_i2c.c:
2084 - activate i2c driver with CONFIG_SYS_I2C_FSL
2085 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2086 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2087 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2088 bus.
93e14596 2089 - If your board supports a second fsl i2c bus, define
00f792e0
HS
2090 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2091 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2092 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2093 second bus.
2094
1f2ba722 2095 - drivers/i2c/tegra_i2c.c:
10cee516
NI
2096 - activate this driver with CONFIG_SYS_I2C_TEGRA
2097 - This driver adds 4 i2c buses with a fix speed from
2098 100000 and the slave addr 0!
1f2ba722 2099
880540de
DE
2100 - drivers/i2c/ppc4xx_i2c.c
2101 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2102 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2103 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2104
fac96408 2105 - drivers/i2c/i2c_mxc.c
2106 - activate this driver with CONFIG_SYS_I2C_MXC
2107 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2108 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2109 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2110 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2111 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2112 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2113 If thoses defines are not set, default value is 100000
2114 for speed, and 0 for slave.
2115
1086bfa9
NI
2116 - drivers/i2c/rcar_i2c.c:
2117 - activate this driver with CONFIG_SYS_I2C_RCAR
2118 - This driver adds 4 i2c buses
2119
2120 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2121 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2122 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2123 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2124 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2125 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2126 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2127 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2128 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2129
2035d77d
NI
2130 - drivers/i2c/sh_i2c.c:
2131 - activate this driver with CONFIG_SYS_I2C_SH
2132 - This driver adds from 2 to 5 i2c buses
2133
2134 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2135 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2136 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2137 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2138 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2139 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2140 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2141 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2142 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2143 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2144 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2145 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2146 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2147
6789e84e
HS
2148 - drivers/i2c/omap24xx_i2c.c
2149 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2150 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2151 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2152 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2153 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2154 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2155 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2156 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2157 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2158 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2159 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2160
0bdffe71
HS
2161 - drivers/i2c/zynq_i2c.c
2162 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2163 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2164 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2165
e717fc6d
NKC
2166 - drivers/i2c/s3c24x0_i2c.c:
2167 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2168 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2169 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2170 with a fix speed from 100000 and the slave addr 0!
2171
3f4978c7
HS
2172 additional defines:
2173
2174 CONFIG_SYS_NUM_I2C_BUSES
2175 Hold the number of i2c busses you want to use. If you
2176 don't use/have i2c muxes on your i2c bus, this
2177 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2178 omit this define.
2179
2180 CONFIG_SYS_I2C_DIRECT_BUS
2181 define this, if you don't use i2c muxes on your hardware.
2182 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2183 omit this define.
2184
2185 CONFIG_SYS_I2C_MAX_HOPS
2186 define how many muxes are maximal consecutively connected
2187 on one i2c bus. If you not use i2c muxes, omit this
2188 define.
2189
2190 CONFIG_SYS_I2C_BUSES
2191 hold a list of busses you want to use, only used if
2192 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2193 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2194 CONFIG_SYS_NUM_I2C_BUSES = 9:
2195
2196 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2197 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2198 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2199 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2200 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2201 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2202 {1, {I2C_NULL_HOP}}, \
2203 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2204 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2205 }
2206
2207 which defines
2208 bus 0 on adapter 0 without a mux
ea818dbb
HS
2209 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2210 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2211 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2212 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2213 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
3f4978c7 2214 bus 6 on adapter 1 without a mux
ea818dbb
HS
2215 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2216 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
3f4978c7
HS
2217
2218 If you do not have i2c muxes on your board, omit this define.
2219
ea818dbb 2220- Legacy I2C Support: CONFIG_HARD_I2C
3f4978c7
HS
2221
2222 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2223 provides the following compelling advantages:
2224
2225 - more than one i2c adapter is usable
2226 - approved multibus support
2227 - better i2c mux support
2228
2229 ** Please consider updating your I2C driver now. **
2230
ea818dbb
HS
2231 These enable legacy I2C serial bus commands. Defining
2232 CONFIG_HARD_I2C will include the appropriate I2C driver
2233 for the selected CPU.
c609719b 2234
945af8d7 2235 This will allow you to use i2c commands at the u-boot
602ad3b3 2236 command line (as long as you set CONFIG_CMD_I2C in
b37c7e5e
WD
2237 CONFIG_COMMANDS) and communicate with i2c based realtime
2238 clock chips. See common/cmd_i2c.c for a description of the
43d9616c 2239 command line interface.
c609719b 2240
bb99ad6d 2241 CONFIG_HARD_I2C selects a hardware I2C controller.
b37c7e5e 2242
945af8d7 2243 There are several other quantities that must also be
ea818dbb 2244 defined when you define CONFIG_HARD_I2C.
c609719b 2245
6d0f6bcf 2246 In both cases you will need to define CONFIG_SYS_I2C_SPEED
945af8d7 2247 to be the frequency (in Hz) at which you wish your i2c bus
6d0f6bcf 2248 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
11ccc33f 2249 the CPU's i2c node address).
945af8d7 2250
8d321b81 2251 Now, the u-boot i2c code for the mpc8xx
a47a12be 2252 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
8d321b81
PT
2253 and so its address should therefore be cleared to 0 (See,
2254 eg, MPC823e User's Manual p.16-473). So, set
2255 CONFIG_SYS_I2C_SLAVE to 0.
c609719b 2256
5da71efa
EM
2257 CONFIG_SYS_I2C_INIT_MPC5XXX
2258
2259 When a board is reset during an i2c bus transfer
2260 chips might think that the current transfer is still
2261 in progress. Reset the slave devices by sending start
2262 commands until the slave device responds.
2263
945af8d7 2264 That's all that's required for CONFIG_HARD_I2C.
c609719b 2265
ea818dbb 2266 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
b37c7e5e
WD
2267 then the following macros need to be defined (examples are
2268 from include/configs/lwmon.h):
c609719b
WD
2269
2270 I2C_INIT
2271
b37c7e5e 2272 (Optional). Any commands necessary to enable the I2C
43d9616c 2273 controller or configure ports.
c609719b 2274
ba56f625 2275 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
b37c7e5e 2276
c609719b
WD
2277 I2C_PORT
2278
43d9616c
WD
2279 (Only for MPC8260 CPU). The I/O port to use (the code
2280 assumes both bits are on the same port). Valid values
2281 are 0..3 for ports A..D.
c609719b
WD
2282
2283 I2C_ACTIVE
2284
2285 The code necessary to make the I2C data line active
2286 (driven). If the data line is open collector, this
2287 define can be null.
2288
b37c7e5e
WD
2289 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2290
c609719b
WD
2291 I2C_TRISTATE
2292
2293 The code necessary to make the I2C data line tri-stated
2294 (inactive). If the data line is open collector, this
2295 define can be null.
2296
b37c7e5e
WD
2297 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2298
c609719b
WD
2299 I2C_READ
2300
472d5460
YS
2301 Code that returns true if the I2C data line is high,
2302 false if it is low.
c609719b 2303
b37c7e5e
WD
2304 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2305
c609719b
WD
2306 I2C_SDA(bit)
2307
472d5460
YS
2308 If <bit> is true, sets the I2C data line high. If it
2309 is false, it clears it (low).
c609719b 2310
b37c7e5e 2311 eg: #define I2C_SDA(bit) \
2535d602 2312 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
ba56f625 2313 else immr->im_cpm.cp_pbdat &= ~PB_SDA
b37c7e5e 2314
c609719b
WD
2315 I2C_SCL(bit)
2316
472d5460
YS
2317 If <bit> is true, sets the I2C clock line high. If it
2318 is false, it clears it (low).
c609719b 2319
b37c7e5e 2320 eg: #define I2C_SCL(bit) \
2535d602 2321 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
ba56f625 2322 else immr->im_cpm.cp_pbdat &= ~PB_SCL
b37c7e5e 2323
c609719b
WD
2324 I2C_DELAY
2325
2326 This delay is invoked four times per clock cycle so this
2327 controls the rate of data transfer. The data rate thus
b37c7e5e 2328 is 1 / (I2C_DELAY * 4). Often defined to be something
945af8d7
WD
2329 like:
2330
b37c7e5e 2331 #define I2C_DELAY udelay(2)
c609719b 2332
793b5726
MF
2333 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2334
2335 If your arch supports the generic GPIO framework (asm/gpio.h),
2336 then you may alternatively define the two GPIOs that are to be
2337 used as SCL / SDA. Any of the previous I2C_xxx macros will
2338 have GPIO-based defaults assigned to them as appropriate.
2339
2340 You should define these to the GPIO value as given directly to
2341 the generic GPIO functions.
2342
6d0f6bcf 2343 CONFIG_SYS_I2C_INIT_BOARD
47cd00fa 2344
8bde7f77
WD
2345 When a board is reset during an i2c bus transfer
2346 chips might think that the current transfer is still
2347 in progress. On some boards it is possible to access
2348 the i2c SCLK line directly, either by using the
2349 processor pin as a GPIO or by having a second pin
2350 connected to the bus. If this option is defined a
2351 custom i2c_init_board() routine in boards/xxx/board.c
2352 is run early in the boot sequence.
47cd00fa 2353
26a33504
RR
2354 CONFIG_SYS_I2C_BOARD_LATE_INIT
2355
2356 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2357 defined a custom i2c_board_late_init() routine in
2358 boards/xxx/board.c is run AFTER the operations in i2c_init()
2359 is completed. This callpoint can be used to unreset i2c bus
2360 using CPU i2c controller register accesses for CPUs whose i2c
2361 controller provide such a method. It is called at the end of
2362 i2c_init() to allow i2c_init operations to setup the i2c bus
2363 controller on the CPU (e.g. setting bus speed & slave address).
2364
17ea1177
WD
2365 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2366
2367 This option enables configuration of bi_iic_fast[] flags
2368 in u-boot bd_info structure based on u-boot environment
2369 variable "i2cfast". (see also i2cfast)
2370
bb99ad6d
BW
2371 CONFIG_I2C_MULTI_BUS
2372
2373 This option allows the use of multiple I2C buses, each of which
c0f40859
WD
2374 must have a controller. At any point in time, only one bus is
2375 active. To switch to a different bus, use the 'i2c dev' command.
bb99ad6d
BW
2376 Note that bus numbering is zero-based.
2377
6d0f6bcf 2378 CONFIG_SYS_I2C_NOPROBES
bb99ad6d
BW
2379
2380 This option specifies a list of I2C devices that will be skipped
c0f40859 2381 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
0f89c54b
PT
2382 is set, specify a list of bus-device pairs. Otherwise, specify
2383 a 1D array of device addresses
bb99ad6d
BW
2384
2385 e.g.
2386 #undef CONFIG_I2C_MULTI_BUS
c0f40859 2387 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
bb99ad6d
BW
2388
2389 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2390
c0f40859 2391 #define CONFIG_I2C_MULTI_BUS
6d0f6bcf 2392 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
bb99ad6d
BW
2393
2394 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2395
6d0f6bcf 2396 CONFIG_SYS_SPD_BUS_NUM
be5e6181
TT
2397
2398 If defined, then this indicates the I2C bus number for DDR SPD.
2399 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2400
6d0f6bcf 2401 CONFIG_SYS_RTC_BUS_NUM
0dc018ec
SR
2402
2403 If defined, then this indicates the I2C bus number for the RTC.
2404 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2405
6d0f6bcf 2406 CONFIG_SYS_DTT_BUS_NUM
0dc018ec
SR
2407
2408 If defined, then this indicates the I2C bus number for the DTT.
2409 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2410
6d0f6bcf 2411 CONFIG_SYS_I2C_DTT_ADDR:
9ebbb54f
VG
2412
2413 If defined, specifies the I2C address of the DTT device.
2414 If not defined, then U-Boot uses predefined value for
2415 specified DTT device.
2416
2ac6985a
AD
2417 CONFIG_SOFT_I2C_READ_REPEATED_START
2418
2419 defining this will force the i2c_read() function in
2420 the soft_i2c driver to perform an I2C repeated start
2421 between writing the address pointer and reading the
2422 data. If this define is omitted the default behaviour
2423 of doing a stop-start sequence will be used. Most I2C
2424 devices can use either method, but some require one or
2425 the other.
be5e6181 2426
c609719b
WD
2427- SPI Support: CONFIG_SPI
2428
2429 Enables SPI driver (so far only tested with
2430 SPI EEPROM, also an instance works with Crystal A/D and
2431 D/As on the SACSng board)
2432
6639562e
YS
2433 CONFIG_SH_SPI
2434
2435 Enables the driver for SPI controller on SuperH. Currently
2436 only SH7757 is supported.
2437
c609719b
WD
2438 CONFIG_SPI_X
2439
2440 Enables extended (16-bit) SPI EEPROM addressing.
2441 (symmetrical to CONFIG_I2C_X)
2442
2443 CONFIG_SOFT_SPI
2444
43d9616c
WD
2445 Enables a software (bit-bang) SPI driver rather than
2446 using hardware support. This is a general purpose
2447 driver that only requires three general I/O port pins
2448 (two outputs, one input) to function. If this is
2449 defined, the board configuration must define several
2450 SPI configuration items (port pins to use, etc). For
2451 an example, see include/configs/sacsng.h.
c609719b 2452
04a9e118
BW
2453 CONFIG_HARD_SPI
2454
2455 Enables a hardware SPI driver for general-purpose reads
2456 and writes. As with CONFIG_SOFT_SPI, the board configuration
2457 must define a list of chip-select function pointers.
c0f40859 2458 Currently supported on some MPC8xxx processors. For an
04a9e118
BW
2459 example, see include/configs/mpc8349emds.h.
2460
38254f45
GL
2461 CONFIG_MXC_SPI
2462
2463 Enables the driver for the SPI controllers on i.MX and MXC
2e3cd1cd 2464 SoCs. Currently i.MX31/35/51 are supported.
38254f45 2465
0133502e 2466- FPGA Support: CONFIG_FPGA
c609719b 2467
0133502e
MF
2468 Enables FPGA subsystem.
2469
2470 CONFIG_FPGA_<vendor>
2471
2472 Enables support for specific chip vendors.
2473 (ALTERA, XILINX)
c609719b 2474
0133502e 2475 CONFIG_FPGA_<family>
c609719b 2476
0133502e
MF
2477 Enables support for FPGA family.
2478 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2479
2480 CONFIG_FPGA_COUNT
2481
2482 Specify the number of FPGA devices to support.
c609719b 2483
6d0f6bcf 2484 CONFIG_SYS_FPGA_PROG_FEEDBACK
c609719b 2485
8bde7f77 2486 Enable printing of hash marks during FPGA configuration.
c609719b 2487
6d0f6bcf 2488 CONFIG_SYS_FPGA_CHECK_BUSY
c609719b 2489
43d9616c
WD
2490 Enable checks on FPGA configuration interface busy
2491 status by the configuration function. This option
2492 will require a board or device specific function to
2493 be written.
c609719b
WD
2494
2495 CONFIG_FPGA_DELAY
2496
2497 If defined, a function that provides delays in the FPGA
2498 configuration driver.
2499
6d0f6bcf 2500 CONFIG_SYS_FPGA_CHECK_CTRLC
c609719b
WD
2501 Allow Control-C to interrupt FPGA configuration
2502
6d0f6bcf 2503 CONFIG_SYS_FPGA_CHECK_ERROR
c609719b 2504
43d9616c
WD
2505 Check for configuration errors during FPGA bitfile
2506 loading. For example, abort during Virtex II
2507 configuration if the INIT_B line goes low (which
2508 indicated a CRC error).
c609719b 2509
6d0f6bcf 2510 CONFIG_SYS_FPGA_WAIT_INIT
c609719b 2511
43d9616c
WD
2512 Maximum time to wait for the INIT_B line to deassert
2513 after PROB_B has been deasserted during a Virtex II
2514 FPGA configuration sequence. The default time is 500
11ccc33f 2515 ms.
c609719b 2516
6d0f6bcf 2517 CONFIG_SYS_FPGA_WAIT_BUSY
c609719b 2518
43d9616c 2519 Maximum time to wait for BUSY to deassert during
11ccc33f 2520 Virtex II FPGA configuration. The default is 5 ms.
c609719b 2521
6d0f6bcf 2522 CONFIG_SYS_FPGA_WAIT_CONFIG
c609719b 2523
43d9616c 2524 Time to wait after FPGA configuration. The default is
11ccc33f 2525 200 ms.
c609719b
WD
2526
2527- Configuration Management:
2528 CONFIG_IDENT_STRING
2529
43d9616c
WD
2530 If defined, this string will be added to the U-Boot
2531 version information (U_BOOT_VERSION)
c609719b
WD
2532
2533- Vendor Parameter Protection:
2534
43d9616c
WD
2535 U-Boot considers the values of the environment
2536 variables "serial#" (Board Serial Number) and
7152b1d0 2537 "ethaddr" (Ethernet Address) to be parameters that
43d9616c
WD
2538 are set once by the board vendor / manufacturer, and
2539 protects these variables from casual modification by
2540 the user. Once set, these variables are read-only,
2541 and write or delete attempts are rejected. You can
11ccc33f 2542 change this behaviour:
c609719b
WD
2543
2544 If CONFIG_ENV_OVERWRITE is #defined in your config
2545 file, the write protection for vendor parameters is
47cd00fa 2546 completely disabled. Anybody can change or delete
c609719b
WD
2547 these parameters.
2548
2549 Alternatively, if you #define _both_ CONFIG_ETHADDR
2550 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
11ccc33f 2551 Ethernet address is installed in the environment,
c609719b
WD
2552 which can be changed exactly ONCE by the user. [The
2553 serial# is unaffected by this, i. e. it remains
2554 read-only.]
2555
2598090b
JH
2556 The same can be accomplished in a more flexible way
2557 for any variable by configuring the type of access
2558 to allow for those variables in the ".flags" variable
2559 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2560
c609719b
WD
2561- Protected RAM:
2562 CONFIG_PRAM
2563
2564 Define this variable to enable the reservation of
2565 "protected RAM", i. e. RAM which is not overwritten
2566 by U-Boot. Define CONFIG_PRAM to hold the number of
2567 kB you want to reserve for pRAM. You can overwrite
2568 this default value by defining an environment
2569 variable "pram" to the number of kB you want to
2570 reserve. Note that the board info structure will
2571 still show the full amount of RAM. If pRAM is
2572 reserved, a new environment variable "mem" will
2573 automatically be defined to hold the amount of
2574 remaining RAM in a form that can be passed as boot
2575 argument to Linux, for instance like that:
2576
fe126d8b 2577 setenv bootargs ... mem=\${mem}
c609719b
WD
2578 saveenv
2579
2580 This way you can tell Linux not to use this memory,
2581 either, which results in a memory region that will
2582 not be affected by reboots.
2583
2584 *WARNING* If your board configuration uses automatic
2585 detection of the RAM size, you must make sure that
2586 this memory test is non-destructive. So far, the
2587 following board configurations are known to be
2588 "pRAM-clean":
2589
1b0757ec
WD
2590 IVMS8, IVML24, SPD8xx, TQM8xxL,
2591 HERMES, IP860, RPXlite, LWMON,
544d97e9 2592 FLAGADM, TQM8260
c609719b 2593
40fef049
GB
2594- Access to physical memory region (> 4GB)
2595 Some basic support is provided for operations on memory not
2596 normally accessible to U-Boot - e.g. some architectures
2597 support access to more than 4GB of memory on 32-bit
2598 machines using physical address extension or similar.
2599 Define CONFIG_PHYSMEM to access this basic support, which
2600 currently only supports clearing the memory.
2601
c609719b
WD
2602- Error Recovery:
2603 CONFIG_PANIC_HANG
2604
2605 Define this variable to stop the system in case of a
2606 fatal error, so that you have to reset it manually.
2607 This is probably NOT a good idea for an embedded
11ccc33f 2608 system where you want the system to reboot
c609719b
WD
2609 automatically as fast as possible, but it may be
2610 useful during development since you can try to debug
2611 the conditions that lead to the situation.
2612
2613 CONFIG_NET_RETRY_COUNT
2614
43d9616c
WD
2615 This variable defines the number of retries for
2616 network operations like ARP, RARP, TFTP, or BOOTP
2617 before giving up the operation. If not defined, a
2618 default value of 5 is used.
c609719b 2619
40cb90ee
GL
2620 CONFIG_ARP_TIMEOUT
2621
2622 Timeout waiting for an ARP reply in milliseconds.
2623
48a3e999
TK
2624 CONFIG_NFS_TIMEOUT
2625
2626 Timeout in milliseconds used in NFS protocol.
2627 If you encounter "ERROR: Cannot umount" in nfs command,
2628 try longer timeout such as
2629 #define CONFIG_NFS_TIMEOUT 10000UL
2630
c609719b 2631- Command Interpreter:
8078f1a5 2632 CONFIG_AUTO_COMPLETE
04a85b3b
WD
2633
2634 Enable auto completion of commands using TAB.
2635
a9398e01
WD
2636 Note that this feature has NOT been implemented yet
2637 for the "hush" shell.
8078f1a5
WD
2638
2639
6d0f6bcf 2640 CONFIG_SYS_HUSH_PARSER
c609719b
WD
2641
2642 Define this variable to enable the "hush" shell (from
2643 Busybox) as command line interpreter, thus enabling
2644 powerful command line syntax like
2645 if...then...else...fi conditionals or `&&' and '||'
2646 constructs ("shell scripts").
2647
2648 If undefined, you get the old, much simpler behaviour
2649 with a somewhat smaller memory footprint.
2650
2651
6d0f6bcf 2652 CONFIG_SYS_PROMPT_HUSH_PS2
c609719b
WD
2653
2654 This defines the secondary prompt string, which is
2655 printed when the command interpreter needs more input
2656 to complete a command. Usually "> ".
2657
2658 Note:
2659
8bde7f77
WD
2660 In the current implementation, the local variables
2661 space and global environment variables space are
2662 separated. Local variables are those you define by
2663 simply typing `name=value'. To access a local
2664 variable later on, you have write `$name' or
2665 `${name}'; to execute the contents of a variable
2666 directly type `$name' at the command prompt.
c609719b 2667
43d9616c
WD
2668 Global environment variables are those you use
2669 setenv/printenv to work with. To run a command stored
2670 in such a variable, you need to use the run command,
2671 and you must not use the '$' sign to access them.
c609719b
WD
2672
2673 To store commands and special characters in a
2674 variable, please use double quotation marks
2675 surrounding the whole text of the variable, instead
2676 of the backslashes before semicolons and special
2677 symbols.
2678
aa0c71ac
WD
2679- Commandline Editing and History:
2680 CONFIG_CMDLINE_EDITING
2681
11ccc33f 2682 Enable editing and History functions for interactive
b9365a26 2683 commandline input operations
aa0c71ac 2684
a8c7c708 2685- Default Environment:
c609719b
WD
2686 CONFIG_EXTRA_ENV_SETTINGS
2687
43d9616c
WD
2688 Define this to contain any number of null terminated
2689 strings (variable = value pairs) that will be part of
7152b1d0 2690 the default environment compiled into the boot image.
2262cfee 2691
43d9616c
WD
2692 For example, place something like this in your
2693 board's config file:
c609719b
WD
2694
2695 #define CONFIG_EXTRA_ENV_SETTINGS \
2696 "myvar1=value1\0" \
2697 "myvar2=value2\0"
2698
43d9616c
WD
2699 Warning: This method is based on knowledge about the
2700 internal format how the environment is stored by the
2701 U-Boot code. This is NOT an official, exported
2702 interface! Although it is unlikely that this format
7152b1d0 2703 will change soon, there is no guarantee either.
c609719b
WD
2704 You better know what you are doing here.
2705
43d9616c
WD
2706 Note: overly (ab)use of the default environment is
2707 discouraged. Make sure to check other ways to preset
74de7aef 2708 the environment like the "source" command or the
43d9616c 2709 boot command first.
c609719b 2710
5e724ca2
SW
2711 CONFIG_ENV_VARS_UBOOT_CONFIG
2712
2713 Define this in order to add variables describing the
2714 U-Boot build configuration to the default environment.
2715 These will be named arch, cpu, board, vendor, and soc.
2716
2717 Enabling this option will cause the following to be defined:
2718
2719 - CONFIG_SYS_ARCH
2720 - CONFIG_SYS_CPU
2721 - CONFIG_SYS_BOARD
2722 - CONFIG_SYS_VENDOR
2723 - CONFIG_SYS_SOC
2724
7e27f89f
TR
2725 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2726
2727 Define this in order to add variables describing certain
2728 run-time determined information about the hardware to the
2729 environment. These will be named board_name, board_rev.
2730
06fd8538
SG
2731 CONFIG_DELAY_ENVIRONMENT
2732
2733 Normally the environment is loaded when the board is
2734 intialised so that it is available to U-Boot. This inhibits
2735 that so that the environment is not available until
2736 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2737 this is instead controlled by the value of
2738 /config/load-environment.
2739
a8c7c708 2740- DataFlash Support:
2abbe075
WD
2741 CONFIG_HAS_DATAFLASH
2742
8bde7f77
WD
2743 Defining this option enables DataFlash features and
2744 allows to read/write in Dataflash via the standard
2745 commands cp, md...
2abbe075 2746
f61ec45e
EN
2747- Serial Flash support
2748 CONFIG_CMD_SF
2749
2750 Defining this option enables SPI flash commands
2751 'sf probe/read/write/erase/update'.
2752
2753 Usage requires an initial 'probe' to define the serial
2754 flash parameters, followed by read/write/erase/update
2755 commands.
2756
2757 The following defaults may be provided by the platform
2758 to handle the common case when only a single serial
2759 flash is present on the system.
2760
2761 CONFIG_SF_DEFAULT_BUS Bus identifier
2762 CONFIG_SF_DEFAULT_CS Chip-select
2763 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2764 CONFIG_SF_DEFAULT_SPEED in Hz
2765
24007273
SG
2766 CONFIG_CMD_SF_TEST
2767
2768 Define this option to include a destructive SPI flash
2769 test ('sf test').
2770
1dcd6d03
JT
2771 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2772
2773 Define this option to use the Bank addr/Extended addr
2774 support on SPI flashes which has size > 16Mbytes.
2775
b902e07c
JT
2776 CONFIG_SF_DUAL_FLASH Dual flash memories
2777
2778 Define this option to use dual flash support where two flash
2779 memories can be connected with a given cs line.
2780 currently Xilinx Zynq qspi support these type of connections.
2781
3f85ce27
WD
2782- SystemACE Support:
2783 CONFIG_SYSTEMACE
2784
2785 Adding this option adds support for Xilinx SystemACE
2786 chips attached via some sort of local bus. The address
11ccc33f 2787 of the chip must also be defined in the
6d0f6bcf 2788 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
3f85ce27
WD
2789
2790 #define CONFIG_SYSTEMACE
6d0f6bcf 2791 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
3f85ce27
WD
2792
2793 When SystemACE support is added, the "ace" device type
2794 becomes available to the fat commands, i.e. fatls.
2795
ecb0ccd9
WD
2796- TFTP Fixed UDP Port:
2797 CONFIG_TFTP_PORT
2798
28cb9375 2799 If this is defined, the environment variable tftpsrcp
ecb0ccd9 2800 is used to supply the TFTP UDP source port value.
28cb9375 2801 If tftpsrcp isn't defined, the normal pseudo-random port
ecb0ccd9
WD
2802 number generator is used.
2803
28cb9375
WD
2804 Also, the environment variable tftpdstp is used to supply
2805 the TFTP UDP destination port value. If tftpdstp isn't
2806 defined, the normal port 69 is used.
2807
2808 The purpose for tftpsrcp is to allow a TFTP server to
ecb0ccd9
WD
2809 blindly start the TFTP transfer using the pre-configured
2810 target IP address and UDP port. This has the effect of
2811 "punching through" the (Windows XP) firewall, allowing
2812 the remainder of the TFTP transfer to proceed normally.
2813 A better solution is to properly configure the firewall,
2814 but sometimes that is not allowed.
2815
bf36c5d5
SG
2816- Hashing support:
2817 CONFIG_CMD_HASH
2818
2819 This enables a generic 'hash' command which can produce
2820 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2821
2822 CONFIG_HASH_VERIFY
2823
2824 Enable the hash verify command (hash -v). This adds to code
2825 size a little.
2826
2827 CONFIG_SHA1 - support SHA1 hashing
2828 CONFIG_SHA256 - support SHA256 hashing
2829
2830 Note: There is also a sha1sum command, which should perhaps
2831 be deprecated in favour of 'hash sha1'.
2832
a11f1873
RW
2833- Freescale i.MX specific commands:
2834 CONFIG_CMD_HDMIDETECT
2835 This enables 'hdmidet' command which returns true if an
2836 HDMI monitor is detected. This command is i.MX 6 specific.
2837
2838 CONFIG_CMD_BMODE
2839 This enables the 'bmode' (bootmode) command for forcing
2840 a boot from specific media.
2841
2842 This is useful for forcing the ROM's usb downloader to
2843 activate upon a watchdog reset which is nice when iterating
2844 on U-Boot. Using the reset button or running bmode normal
2845 will set it back to normal. This command currently
2846 supports i.MX53 and i.MX6.
2847
19c402af
SG
2848- Signing support:
2849 CONFIG_RSA
2850
2851 This enables the RSA algorithm used for FIT image verification
8bf2aad7 2852 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
19c402af
SG
2853
2854 The signing part is build into mkimage regardless of this
2855 option.
2856
2857
a8c7c708 2858- Show boot progress:
c609719b
WD
2859 CONFIG_SHOW_BOOT_PROGRESS
2860
43d9616c
WD
2861 Defining this option allows to add some board-
2862 specific code (calling a user-provided function
2863 "show_boot_progress(int)") that enables you to show
2864 the system's boot progress on some display (for
2865 example, some LED's) on your board. At the moment,
2866 the following checkpoints are implemented:
c609719b 2867
3a608ca0
SG
2868- Detailed boot stage timing
2869 CONFIG_BOOTSTAGE
2870 Define this option to get detailed timing of each stage
2871 of the boot process.
2872
2873 CONFIG_BOOTSTAGE_USER_COUNT
2874 This is the number of available user bootstage records.
2875 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2876 a new ID will be allocated from this stash. If you exceed
2877 the limit, recording will stop.
2878
2879 CONFIG_BOOTSTAGE_REPORT
2880 Define this to print a report before boot, similar to this:
2881
2882 Timer summary in microseconds:
2883 Mark Elapsed Stage
2884 0 0 reset
2885 3,575,678 3,575,678 board_init_f start
2886 3,575,695 17 arch_cpu_init A9
2887 3,575,777 82 arch_cpu_init done
2888 3,659,598 83,821 board_init_r start
2889 3,910,375 250,777 main_loop
2890 29,916,167 26,005,792 bootm_start
2891 30,361,327 445,160 start_kernel
2892
2eba38cf
SG
2893 CONFIG_CMD_BOOTSTAGE
2894 Add a 'bootstage' command which supports printing a report
2895 and un/stashing of bootstage data.
2896
94fd1316
SG
2897 CONFIG_BOOTSTAGE_FDT
2898 Stash the bootstage information in the FDT. A root 'bootstage'
2899 node is created with each bootstage id as a child. Each child
2900 has a 'name' property and either 'mark' containing the
2901 mark time in microsecond, or 'accum' containing the
2902 accumulated time for that bootstage id in microseconds.
2903 For example:
2904
2905 bootstage {
2906 154 {
2907 name = "board_init_f";
2908 mark = <3575678>;
2909 };
2910 170 {
2911 name = "lcd";
2912 accum = <33482>;
2913 };
2914 };
2915
2916 Code in the Linux kernel can find this in /proc/devicetree.
2917
1372cce2
MB
2918Legacy uImage format:
2919
c609719b
WD
2920 Arg Where When
2921 1 common/cmd_bootm.c before attempting to boot an image
ba56f625 2922 -1 common/cmd_bootm.c Image header has bad magic number
c609719b 2923 2 common/cmd_bootm.c Image header has correct magic number
ba56f625 2924 -2 common/cmd_bootm.c Image header has bad checksum
c609719b 2925 3 common/cmd_bootm.c Image header has correct checksum
ba56f625 2926 -3 common/cmd_bootm.c Image data has bad checksum
c609719b
WD
2927 4 common/cmd_bootm.c Image data has correct checksum
2928 -4 common/cmd_bootm.c Image is for unsupported architecture
2929 5 common/cmd_bootm.c Architecture check OK
1372cce2 2930 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
c609719b
WD
2931 6 common/cmd_bootm.c Image Type check OK
2932 -6 common/cmd_bootm.c gunzip uncompression error
2933 -7 common/cmd_bootm.c Unimplemented compression type
2934 7 common/cmd_bootm.c Uncompression OK
1372cce2 2935 8 common/cmd_bootm.c No uncompress/copy overwrite error
c609719b 2936 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1372cce2
MB
2937
2938 9 common/image.c Start initial ramdisk verification
2939 -10 common/image.c Ramdisk header has bad magic number
2940 -11 common/image.c Ramdisk header has bad checksum
2941 10 common/image.c Ramdisk header is OK
2942 -12 common/image.c Ramdisk data has bad checksum
2943 11 common/image.c Ramdisk data has correct checksum
2944 12 common/image.c Ramdisk verification complete, start loading
11ccc33f 2945 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1372cce2
MB
2946 13 common/image.c Start multifile image verification
2947 14 common/image.c No initial ramdisk, no multifile, continue.
2948
c0f40859 2949 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
c609719b 2950
a47a12be 2951 -30 arch/powerpc/lib/board.c Fatal error, hang the system
11dadd54
WD
2952 -31 post/post.c POST test failed, detected by post_output_backlog()
2953 -32 post/post.c POST test failed, detected by post_run_single()
63e73c9a 2954
566a494f
HS
2955 34 common/cmd_doc.c before loading a Image from a DOC device
2956 -35 common/cmd_doc.c Bad usage of "doc" command
2957 35 common/cmd_doc.c correct usage of "doc" command
2958 -36 common/cmd_doc.c No boot device
2959 36 common/cmd_doc.c correct boot device
2960 -37 common/cmd_doc.c Unknown Chip ID on boot device
2961 37 common/cmd_doc.c correct chip ID found, device available
2962 -38 common/cmd_doc.c Read Error on boot device
2963 38 common/cmd_doc.c reading Image header from DOC device OK
2964 -39 common/cmd_doc.c Image header has bad magic number
2965 39 common/cmd_doc.c Image header has correct magic number
2966 -40 common/cmd_doc.c Error reading Image from DOC device
2967 40 common/cmd_doc.c Image header has correct magic number
2968 41 common/cmd_ide.c before loading a Image from a IDE device
2969 -42 common/cmd_ide.c Bad usage of "ide" command
2970 42 common/cmd_ide.c correct usage of "ide" command
2971 -43 common/cmd_ide.c No boot device
2972 43 common/cmd_ide.c boot device found
2973 -44 common/cmd_ide.c Device not available
2974 44 common/cmd_ide.c Device available
2975 -45 common/cmd_ide.c wrong partition selected
2976 45 common/cmd_ide.c partition selected
2977 -46 common/cmd_ide.c Unknown partition table
2978 46 common/cmd_ide.c valid partition table found
2979 -47 common/cmd_ide.c Invalid partition type
2980 47 common/cmd_ide.c correct partition type
2981 -48 common/cmd_ide.c Error reading Image Header on boot device
2982 48 common/cmd_ide.c reading Image Header from IDE device OK
2983 -49 common/cmd_ide.c Image header has bad magic number
2984 49 common/cmd_ide.c Image header has correct magic number
2985 -50 common/cmd_ide.c Image header has bad checksum
2986 50 common/cmd_ide.c Image header has correct checksum
2987 -51 common/cmd_ide.c Error reading Image from IDE device
2988 51 common/cmd_ide.c reading Image from IDE device OK
2989 52 common/cmd_nand.c before loading a Image from a NAND device
2990 -53 common/cmd_nand.c Bad usage of "nand" command
2991 53 common/cmd_nand.c correct usage of "nand" command
2992 -54 common/cmd_nand.c No boot device
2993 54 common/cmd_nand.c boot device found
2994 -55 common/cmd_nand.c Unknown Chip ID on boot device
2995 55 common/cmd_nand.c correct chip ID found, device available
2996 -56 common/cmd_nand.c Error reading Image Header on boot device
2997 56 common/cmd_nand.c reading Image Header from NAND device OK
2998 -57 common/cmd_nand.c Image header has bad magic number
2999 57 common/cmd_nand.c Image header has correct magic number
3000 -58 common/cmd_nand.c Error reading Image from NAND device
3001 58 common/cmd_nand.c reading Image from NAND device OK
3002
3003 -60 common/env_common.c Environment has a bad CRC, using default
3004
11ccc33f 3005 64 net/eth.c starting with Ethernet configuration.
566a494f
HS
3006 -64 net/eth.c no Ethernet found.
3007 65 net/eth.c Ethernet found.
3008
3009 -80 common/cmd_net.c usage wrong
3010 80 common/cmd_net.c before calling NetLoop()
11ccc33f 3011 -81 common/cmd_net.c some error in NetLoop() occurred
566a494f
HS
3012 81 common/cmd_net.c NetLoop() back without error
3013 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3014 82 common/cmd_net.c trying automatic boot
74de7aef
WD
3015 83 common/cmd_net.c running "source" command
3016 -83 common/cmd_net.c some error in automatic boot or "source" command
566a494f 3017 84 common/cmd_net.c end without errors
c609719b 3018
1372cce2
MB
3019FIT uImage format:
3020
3021 Arg Where When
3022 100 common/cmd_bootm.c Kernel FIT Image has correct format
3023 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3024 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3025 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3026 102 common/cmd_bootm.c Kernel unit name specified
3027 -103 common/cmd_bootm.c Can't get kernel subimage node offset
f773bea8 3028 103 common/cmd_bootm.c Found configuration node
1372cce2
MB
3029 104 common/cmd_bootm.c Got kernel subimage node offset
3030 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3031 105 common/cmd_bootm.c Kernel subimage hash verification OK
3032 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3033 106 common/cmd_bootm.c Architecture check OK
11ccc33f
MZ
3034 -106 common/cmd_bootm.c Kernel subimage has wrong type
3035 107 common/cmd_bootm.c Kernel subimage type OK
1372cce2
MB
3036 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3037 108 common/cmd_bootm.c Got kernel subimage data/size
3038 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3039 -109 common/cmd_bootm.c Can't get kernel subimage type
3040 -110 common/cmd_bootm.c Can't get kernel subimage comp
3041 -111 common/cmd_bootm.c Can't get kernel subimage os
3042 -112 common/cmd_bootm.c Can't get kernel subimage load address
3043 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3044
3045 120 common/image.c Start initial ramdisk verification
3046 -120 common/image.c Ramdisk FIT image has incorrect format
3047 121 common/image.c Ramdisk FIT image has correct format
11ccc33f 3048 122 common/image.c No ramdisk subimage unit name, using configuration
1372cce2
MB
3049 -122 common/image.c Can't get configuration for ramdisk subimage
3050 123 common/image.c Ramdisk unit name specified
3051 -124 common/image.c Can't get ramdisk subimage node offset
3052 125 common/image.c Got ramdisk subimage node offset
3053 -125 common/image.c Ramdisk subimage hash verification failed
3054 126 common/image.c Ramdisk subimage hash verification OK
3055 -126 common/image.c Ramdisk subimage for unsupported architecture
3056 127 common/image.c Architecture check OK
3057 -127 common/image.c Can't get ramdisk subimage data/size
3058 128 common/image.c Got ramdisk subimage data/size
3059 129 common/image.c Can't get ramdisk load address
3060 -129 common/image.c Got ramdisk load address
3061
11ccc33f 3062 -130 common/cmd_doc.c Incorrect FIT image format
1372cce2
MB
3063 131 common/cmd_doc.c FIT image format OK
3064
11ccc33f 3065 -140 common/cmd_ide.c Incorrect FIT image format
1372cce2
MB
3066 141 common/cmd_ide.c FIT image format OK
3067
11ccc33f 3068 -150 common/cmd_nand.c Incorrect FIT image format
1372cce2
MB
3069 151 common/cmd_nand.c FIT image format OK
3070
d95f6ec7
GB
3071- FIT image support:
3072 CONFIG_FIT
3073 Enable support for the FIT uImage format.
3074
3075 CONFIG_FIT_BEST_MATCH
3076 When no configuration is explicitly selected, default to the
3077 one whose fdt's compatibility field best matches that of
3078 U-Boot itself. A match is considered "best" if it matches the
3079 most specific compatibility entry of U-Boot's fdt's root node.
3080 The order of entries in the configuration's fdt is ignored.
3081
3e569a6b
SG
3082 CONFIG_FIT_SIGNATURE
3083 This option enables signature verification of FIT uImages,
3084 using a hash signed and verified using RSA. See
3085 doc/uImage.FIT/signature.txt for more details.
3086
4cf2609b
WD
3087- Standalone program support:
3088 CONFIG_STANDALONE_LOAD_ADDR
3089
6feff899
WD
3090 This option defines a board specific value for the
3091 address where standalone program gets loaded, thus
3092 overwriting the architecture dependent default
4cf2609b
WD
3093 settings.
3094
3095- Frame Buffer Address:
3096 CONFIG_FB_ADDR
3097
3098 Define CONFIG_FB_ADDR if you want to use specific
44a53b57
WD
3099 address for frame buffer. This is typically the case
3100 when using a graphics controller has separate video
3101 memory. U-Boot will then place the frame buffer at
3102 the given address instead of dynamically reserving it
3103 in system RAM by calling lcd_setmem(), which grabs
3104 the memory for the frame buffer depending on the
3105 configured panel size.
4cf2609b
WD
3106
3107 Please see board_init_f function.
3108
cccfc2ab
DZ
3109- Automatic software updates via TFTP server
3110 CONFIG_UPDATE_TFTP
3111 CONFIG_UPDATE_TFTP_CNT_MAX
3112 CONFIG_UPDATE_TFTP_MSEC_MAX
3113
3114 These options enable and control the auto-update feature;
3115 for a more detailed description refer to doc/README.update.
3116
3117- MTD Support (mtdparts command, UBI support)
3118 CONFIG_MTD_DEVICE
3119
3120 Adds the MTD device infrastructure from the Linux kernel.
3121 Needed for mtdparts command support.
3122
3123 CONFIG_MTD_PARTITIONS
3124
3125 Adds the MTD partitioning infrastructure from the Linux
3126 kernel. Needed for UBI support.
3127
70c219cd
JH
3128- UBI support
3129 CONFIG_CMD_UBI
3130
3131 Adds commands for interacting with MTD partitions formatted
3132 with the UBI flash translation layer
3133
3134 Requires also defining CONFIG_RBTREE
3135
147162da
JH
3136 CONFIG_UBI_SILENCE_MSG
3137
3138 Make the verbose messages from UBI stop printing. This leaves
3139 warnings and errors enabled.
3140
70c219cd
JH
3141- UBIFS support
3142 CONFIG_CMD_UBIFS
3143
3144 Adds commands for interacting with UBI volumes formatted as
3145 UBIFS. UBIFS is read-only in u-boot.
3146
3147 Requires UBI support as well as CONFIG_LZO
3148
147162da
JH
3149 CONFIG_UBIFS_SILENCE_MSG
3150
3151 Make the verbose messages from UBIFS stop printing. This leaves
3152 warnings and errors enabled.
3153
6a11cf48 3154- SPL framework
04e5ae79
WD
3155 CONFIG_SPL
3156 Enable building of SPL globally.
6a11cf48 3157
95579793
TR
3158 CONFIG_SPL_LDSCRIPT
3159 LDSCRIPT for linking the SPL binary.
3160
6ebc3461
AA
3161 CONFIG_SPL_MAX_FOOTPRINT
3162 Maximum size in memory allocated to the SPL, BSS included.
3163 When defined, the linker checks that the actual memory
3164 used by SPL from _start to __bss_end does not exceed it.
8960af8b 3165 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
3166 must not be both defined at the same time.
3167
95579793 3168 CONFIG_SPL_MAX_SIZE
6ebc3461
AA
3169 Maximum size of the SPL image (text, data, rodata, and
3170 linker lists sections), BSS excluded.
3171 When defined, the linker checks that the actual size does
3172 not exceed it.
95579793 3173
04e5ae79
WD
3174 CONFIG_SPL_TEXT_BASE
3175 TEXT_BASE for linking the SPL binary.
6a11cf48 3176
94a45bb1
SW
3177 CONFIG_SPL_RELOC_TEXT_BASE
3178 Address to relocate to. If unspecified, this is equal to
3179 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3180
95579793
TR
3181 CONFIG_SPL_BSS_START_ADDR
3182 Link address for the BSS within the SPL binary.
3183
3184 CONFIG_SPL_BSS_MAX_SIZE
6ebc3461
AA
3185 Maximum size in memory allocated to the SPL BSS.
3186 When defined, the linker checks that the actual memory used
3187 by SPL from __bss_start to __bss_end does not exceed it.
8960af8b 3188 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
6ebc3461 3189 must not be both defined at the same time.
95579793
TR
3190
3191 CONFIG_SPL_STACK
3192 Adress of the start of the stack SPL will use
3193
94a45bb1
SW
3194 CONFIG_SPL_RELOC_STACK
3195 Adress of the start of the stack SPL will use after
3196 relocation. If unspecified, this is equal to
3197 CONFIG_SPL_STACK.
3198
95579793
TR
3199 CONFIG_SYS_SPL_MALLOC_START
3200 Starting address of the malloc pool used in SPL.
3201
3202 CONFIG_SYS_SPL_MALLOC_SIZE
3203 The size of the malloc pool used in SPL.
6a11cf48 3204
47f7bcae
TR
3205 CONFIG_SPL_FRAMEWORK
3206 Enable the SPL framework under common/. This framework
3207 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3208 NAND loading of the Linux Kernel.
3209
861a86f4
TR
3210 CONFIG_SPL_DISPLAY_PRINT
3211 For ARM, enable an optional function to print more information
3212 about the running system.
3213
4b919725
SW
3214 CONFIG_SPL_INIT_MINIMAL
3215 Arch init code should be built for a very small image
3216
04e5ae79
WD
3217 CONFIG_SPL_LIBCOMMON_SUPPORT
3218 Support for common/libcommon.o in SPL binary
6a11cf48 3219
04e5ae79
WD
3220 CONFIG_SPL_LIBDISK_SUPPORT
3221 Support for disk/libdisk.o in SPL binary
6a11cf48 3222
04e5ae79
WD
3223 CONFIG_SPL_I2C_SUPPORT
3224 Support for drivers/i2c/libi2c.o in SPL binary
6a11cf48 3225
04e5ae79
WD
3226 CONFIG_SPL_GPIO_SUPPORT
3227 Support for drivers/gpio/libgpio.o in SPL binary
6a11cf48 3228
04e5ae79
WD
3229 CONFIG_SPL_MMC_SUPPORT
3230 Support for drivers/mmc/libmmc.o in SPL binary
6a11cf48 3231
95579793
TR
3232 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3233 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3234 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3235 Address, size and partition on the MMC to load U-Boot from
3236 when the MMC is being used in raw mode.
3237
2b75b0ad
PK
3238 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3239 Sector to load kernel uImage from when MMC is being
3240 used in raw mode (for Falcon mode)
3241
3242 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3243 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3244 Sector and number of sectors to load kernel argument
3245 parameters from when MMC is being used in raw mode
3246 (for falcon mode)
3247
95579793
TR
3248 CONFIG_SPL_FAT_SUPPORT
3249 Support for fs/fat/libfat.o in SPL binary
3250
3251 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3252 Filename to read to load U-Boot when reading from FAT
3253
7ad2cc79
PK
3254 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3255 Filename to read to load kernel uImage when reading
3256 from FAT (for Falcon mode)
3257
3258 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3259 Filename to read to load kernel argument parameters
3260 when reading from FAT (for Falcon mode)
3261
06f60ae3
SW
3262 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3263 Set this for NAND SPL on PPC mpc83xx targets, so that
3264 start.S waits for the rest of the SPL to load before
3265 continuing (the hardware starts execution after just
3266 loading the first page rather than the full 4K).
3267
6f2f01b9
SW
3268 CONFIG_SPL_NAND_BASE
3269 Include nand_base.c in the SPL. Requires
3270 CONFIG_SPL_NAND_DRIVERS.
3271
3272 CONFIG_SPL_NAND_DRIVERS
3273 SPL uses normal NAND drivers, not minimal drivers.
3274
3275 CONFIG_SPL_NAND_ECC
3276 Include standard software ECC in the SPL
3277
95579793 3278 CONFIG_SPL_NAND_SIMPLE
7d4b7955
SW
3279 Support for NAND boot using simple NAND drivers that
3280 expose the cmd_ctrl() interface.
95579793 3281
bb0dc108
YZ
3282 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3283 Set for the SPL on PPC mpc8xxx targets, support for
5614e71b 3284 drivers/ddr/fsl/libddr.o in SPL binary.
bb0dc108 3285
7c8eea59
YZ
3286 CONFIG_SPL_COMMON_INIT_DDR
3287 Set for common ddr init with serial presence detect in
3288 SPL binary.
3289
95579793
TR
3290 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3291 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3292 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3293 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3294 CONFIG_SYS_NAND_ECCBYTES
3295 Defines the size and behavior of the NAND that SPL uses
7d4b7955 3296 to read U-Boot
95579793 3297
fbe76ae4
PK
3298 CONFIG_SPL_NAND_BOOT
3299 Add support NAND boot
3300
95579793 3301 CONFIG_SYS_NAND_U_BOOT_OFFS
7d4b7955
SW
3302 Location in NAND to read U-Boot from
3303
3304 CONFIG_SYS_NAND_U_BOOT_DST
3305 Location in memory to load U-Boot to
3306
3307 CONFIG_SYS_NAND_U_BOOT_SIZE
3308 Size of image to load
95579793
TR
3309
3310 CONFIG_SYS_NAND_U_BOOT_START
7d4b7955 3311 Entry point in loaded image to jump to
95579793
TR
3312
3313 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3314 Define this if you need to first read the OOB and then the
3315 data. This is used for example on davinci plattforms.
3316
3317 CONFIG_SPL_OMAP3_ID_NAND
3318 Support for an OMAP3-specific set of functions to return the
3319 ID and MFR of the first attached NAND chip, if present.
3320
04e5ae79
WD
3321 CONFIG_SPL_SERIAL_SUPPORT
3322 Support for drivers/serial/libserial.o in SPL binary
6a11cf48 3323
04e5ae79
WD
3324 CONFIG_SPL_SPI_FLASH_SUPPORT
3325 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
6a11cf48 3326
04e5ae79
WD
3327 CONFIG_SPL_SPI_SUPPORT
3328 Support for drivers/spi/libspi.o in SPL binary
c57b953d
PM
3329
3330 CONFIG_SPL_RAM_DEVICE
3331 Support for running image already present in ram, in SPL binary
6a11cf48 3332
04e5ae79
WD
3333 CONFIG_SPL_LIBGENERIC_SUPPORT
3334 Support for lib/libgeneric.o in SPL binary
1372cce2 3335
ba1bee43
YZ
3336 CONFIG_SPL_ENV_SUPPORT
3337 Support for the environment operating in SPL binary
3338
3339 CONFIG_SPL_NET_SUPPORT
3340 Support for the net/libnet.o in SPL binary.
3341 It conflicts with SPL env from storage medium specified by
3342 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3343
74752baa 3344 CONFIG_SPL_PAD_TO
6113d3f2
BT
3345 Image offset to which the SPL should be padded before appending
3346 the SPL payload. By default, this is defined as
3347 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3348 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3349 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
74752baa 3350
ca2fca22
SW
3351 CONFIG_SPL_TARGET
3352 Final target image containing SPL and payload. Some SPLs
3353 use an arch-specific makefile fragment instead, for
3354 example if more than one image needs to be produced.
3355
87ebee39
SG
3356 CONFIG_FIT_SPL_PRINT
3357 Printing information about a FIT image adds quite a bit of
3358 code to SPL. So this is normally disabled in SPL. Use this
3359 option to re-enable it. This will affect the output of the
3360 bootm command when booting a FIT image.
3361
3aa29de0
YZ
3362- TPL framework
3363 CONFIG_TPL
3364 Enable building of TPL globally.
3365
3366 CONFIG_TPL_PAD_TO
3367 Image offset to which the TPL should be padded before appending
3368 the TPL payload. By default, this is defined as
93e14596
WD
3369 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3370 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3371 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3aa29de0 3372
c609719b
WD
3373Modem Support:
3374--------------
3375
566e5cf4 3376[so far only for SMDK2400 boards]
c609719b 3377
11ccc33f 3378- Modem support enable:
c609719b
WD
3379 CONFIG_MODEM_SUPPORT
3380
3381- RTS/CTS Flow control enable:
3382 CONFIG_HWFLOW
3383
3384- Modem debug support:
3385 CONFIG_MODEM_SUPPORT_DEBUG
3386
43d9616c
WD
3387 Enables debugging stuff (char screen[1024], dbg())
3388 for modem support. Useful only with BDI2000.
c609719b 3389
a8c7c708
WD
3390- Interrupt support (PPC):
3391
d4ca31c4
WD
3392 There are common interrupt_init() and timer_interrupt()
3393 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
11ccc33f 3394 for CPU specific initialization. interrupt_init_cpu()
d4ca31c4 3395 should set decrementer_count to appropriate value. If
11ccc33f 3396 CPU resets decrementer automatically after interrupt
d4ca31c4 3397 (ppc4xx) it should set decrementer_count to zero.
11ccc33f 3398 timer_interrupt() calls timer_interrupt_cpu() for CPU
d4ca31c4
WD
3399 specific handling. If board has watchdog / status_led
3400 / other_activity_monitor it works automatically from
3401 general timer_interrupt().
a8c7c708 3402
c609719b
WD
3403- General:
3404
43d9616c
WD
3405 In the target system modem support is enabled when a
3406 specific key (key combination) is pressed during
3407 power-on. Otherwise U-Boot will boot normally
11ccc33f 3408 (autoboot). The key_pressed() function is called from
43d9616c
WD
3409 board_init(). Currently key_pressed() is a dummy
3410 function, returning 1 and thus enabling modem
3411 initialization.
c609719b 3412
43d9616c
WD
3413 If there are no modem init strings in the
3414 environment, U-Boot proceed to autoboot; the
3415 previous output (banner, info printfs) will be
11ccc33f 3416 suppressed, though.
c609719b
WD
3417
3418 See also: doc/README.Modem
3419
9660e442
HR
3420Board initialization settings:
3421------------------------------
3422
3423During Initialization u-boot calls a number of board specific functions
3424to allow the preparation of board specific prerequisites, e.g. pin setup
3425before drivers are initialized. To enable these callbacks the
3426following configuration macros have to be defined. Currently this is
3427architecture specific, so please check arch/your_architecture/lib/board.c
3428typically in board_init_f() and board_init_r().
3429
3430- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3431- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3432- CONFIG_BOARD_LATE_INIT: Call board_late_init()
3433- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
c609719b 3434
c609719b
WD
3435Configuration Settings:
3436-----------------------
3437
6d0f6bcf 3438- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
c609719b
WD
3439 undefine this when you're short of memory.
3440
2fb2604d
PT
3441- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3442 width of the commands listed in the 'help' command output.
3443
6d0f6bcf 3444- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
c609719b
WD
3445 prompt for user input.
3446
6d0f6bcf 3447- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
c609719b 3448
6d0f6bcf 3449- CONFIG_SYS_PBSIZE: Buffer size for Console output
c609719b 3450
6d0f6bcf 3451- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
c609719b 3452
6d0f6bcf 3453- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
c609719b
WD
3454 the application (usually a Linux kernel) when it is
3455 booted
3456
6d0f6bcf 3457- CONFIG_SYS_BAUDRATE_TABLE:
c609719b
WD
3458 List of legal baudrate settings for this board.
3459
6d0f6bcf 3460- CONFIG_SYS_CONSOLE_INFO_QUIET
8bde7f77 3461 Suppress display of console information at boot.
c609719b 3462
6d0f6bcf 3463- CONFIG_SYS_CONSOLE_IS_IN_ENV
8bde7f77
WD
3464 If the board specific function
3465 extern int overwrite_console (void);
3466 returns 1, the stdin, stderr and stdout are switched to the
c609719b
WD
3467 serial port, else the settings in the environment are used.
3468
6d0f6bcf 3469- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
8bde7f77 3470 Enable the call to overwrite_console().
c609719b 3471
6d0f6bcf 3472- CONFIG_SYS_CONSOLE_ENV_OVERWRITE
c609719b
WD
3473 Enable overwrite of previous console environment settings.
3474
6d0f6bcf 3475- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
c609719b
WD
3476 Begin and End addresses of the area used by the
3477 simple memory test.
3478
6d0f6bcf 3479- CONFIG_SYS_ALT_MEMTEST:
8bde7f77 3480 Enable an alternate, more extensive memory test.
c609719b 3481
6d0f6bcf 3482- CONFIG_SYS_MEMTEST_SCRATCH:
5f535fe1
WD
3483 Scratch address used by the alternate memory test
3484 You only need to set this if address zero isn't writeable
3485
6d0f6bcf
JCPV
3486- CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3487 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
14f73ca6 3488 this specified memory area will get subtracted from the top
11ccc33f 3489 (end) of RAM and won't get "touched" at all by U-Boot. By
14f73ca6
SR
3490 fixing up gd->ram_size the Linux kernel should gets passed
3491 the now "corrected" memory size and won't touch it either.
3492 This should work for arch/ppc and arch/powerpc. Only Linux
5e12e75d 3493 board ports in arch/powerpc with bootwrapper support that
14f73ca6 3494 recalculate the memory size from the SDRAM controller setup
5e12e75d 3495 will have to get fixed in Linux additionally.
14f73ca6
SR
3496
3497 This option can be used as a workaround for the 440EPx/GRx
3498 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3499 be touched.
3500
3501 WARNING: Please make sure that this value is a multiple of
3502 the Linux page size (normally 4k). If this is not the case,
3503 then the end address of the Linux memory will be located at a
3504 non page size aligned address and this could cause major
3505 problems.
3506
6d0f6bcf 3507- CONFIG_SYS_LOADS_BAUD_CHANGE:
c609719b
WD
3508 Enable temporary baudrate change while serial download
3509
6d0f6bcf 3510- CONFIG_SYS_SDRAM_BASE:
c609719b
WD
3511 Physical start address of SDRAM. _Must_ be 0 here.
3512
6d0f6bcf 3513- CONFIG_SYS_MBIO_BASE:
c609719b
WD
3514 Physical start address of Motherboard I/O (if using a
3515 Cogent motherboard)
3516
6d0f6bcf 3517- CONFIG_SYS_FLASH_BASE:
c609719b
WD
3518 Physical start address of Flash memory.
3519
6d0f6bcf 3520- CONFIG_SYS_MONITOR_BASE:
c609719b
WD
3521 Physical start address of boot monitor code (set by
3522 make config files to be same as the text base address
14d0a02a 3523 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
6d0f6bcf 3524 CONFIG_SYS_FLASH_BASE when booting from flash.
c609719b 3525
6d0f6bcf 3526- CONFIG_SYS_MONITOR_LEN:
8bde7f77
WD
3527 Size of memory reserved for monitor code, used to
3528 determine _at_compile_time_ (!) if the environment is
3529 embedded within the U-Boot image, or in a separate
3530 flash sector.
c609719b 3531
6d0f6bcf 3532- CONFIG_SYS_MALLOC_LEN:
c609719b
WD
3533 Size of DRAM reserved for malloc() use.
3534
6d0f6bcf 3535- CONFIG_SYS_BOOTM_LEN:
15940c9a
SR
3536 Normally compressed uImages are limited to an
3537 uncompressed size of 8 MBytes. If this is not enough,
6d0f6bcf 3538 you can define CONFIG_SYS_BOOTM_LEN in your board config file
15940c9a
SR
3539 to adjust this setting to your needs.
3540
6d0f6bcf 3541- CONFIG_SYS_BOOTMAPSZ:
c609719b
WD
3542 Maximum size of memory mapped by the startup code of
3543 the Linux kernel; all data that must be processed by
7d721e34
BS
3544 the Linux kernel (bd_info, boot arguments, FDT blob if
3545 used) must be put below this limit, unless "bootm_low"
1bce2aeb 3546 environment variable is defined and non-zero. In such case
7d721e34 3547 all data for the Linux kernel must be between "bootm_low"
c0f40859 3548 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
c3624e6e
GL
3549 variable "bootm_mapsize" will override the value of
3550 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3551 then the value in "bootm_size" will be used instead.
c609719b 3552
fca43cc8
JR
3553- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3554 Enable initrd_high functionality. If defined then the
3555 initrd_high feature is enabled and the bootm ramdisk subcommand
3556 is enabled.
3557
3558- CONFIG_SYS_BOOT_GET_CMDLINE:
3559 Enables allocating and saving kernel cmdline in space between
3560 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3561
3562- CONFIG_SYS_BOOT_GET_KBD:
3563 Enables allocating and saving a kernel copy of the bd_info in
3564 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3565
6d0f6bcf 3566- CONFIG_SYS_MAX_FLASH_BANKS:
c609719b
WD
3567 Max number of Flash memory banks
3568
6d0f6bcf 3569- CONFIG_SYS_MAX_FLASH_SECT:
c609719b
WD
3570 Max number of sectors on a Flash chip
3571
6d0f6bcf 3572- CONFIG_SYS_FLASH_ERASE_TOUT:
c609719b
WD
3573 Timeout for Flash erase operations (in ms)
3574
6d0f6bcf 3575- CONFIG_SYS_FLASH_WRITE_TOUT:
c609719b
WD
3576 Timeout for Flash write operations (in ms)
3577
6d0f6bcf 3578- CONFIG_SYS_FLASH_LOCK_TOUT
8564acf9
WD
3579 Timeout for Flash set sector lock bit operation (in ms)
3580
6d0f6bcf 3581- CONFIG_SYS_FLASH_UNLOCK_TOUT
8564acf9
WD
3582 Timeout for Flash clear lock bits operation (in ms)
3583
6d0f6bcf 3584- CONFIG_SYS_FLASH_PROTECTION
8564acf9
WD
3585 If defined, hardware flash sectors protection is used
3586 instead of U-Boot software protection.
3587
6d0f6bcf 3588- CONFIG_SYS_DIRECT_FLASH_TFTP:
c609719b
WD
3589
3590 Enable TFTP transfers directly to flash memory;
3591 without this option such a download has to be
3592 performed in two steps: (1) download to RAM, and (2)
3593 copy from RAM to flash.
3594
3595 The two-step approach is usually more reliable, since
3596 you can check if the download worked before you erase
11ccc33f
MZ
3597 the flash, but in some situations (when system RAM is
3598 too limited to allow for a temporary copy of the
c609719b
WD
3599 downloaded image) this option may be very useful.
3600
6d0f6bcf 3601- CONFIG_SYS_FLASH_CFI:
43d9616c 3602 Define if the flash driver uses extra elements in the
5653fc33
WD
3603 common flash structure for storing flash geometry.
3604
00b1883a 3605- CONFIG_FLASH_CFI_DRIVER
5653fc33
WD
3606 This option also enables the building of the cfi_flash driver
3607 in the drivers directory
c609719b 3608
91809ed5
PZ
3609- CONFIG_FLASH_CFI_MTD
3610 This option enables the building of the cfi_mtd driver
3611 in the drivers directory. The driver exports CFI flash
3612 to the MTD layer.
3613
6d0f6bcf 3614- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
96ef831f
GL
3615 Use buffered writes to flash.
3616
3617- CONFIG_FLASH_SPANSION_S29WS_N
3618 s29ws-n MirrorBit flash has non-standard addresses for buffered
3619 write commands.
3620
6d0f6bcf 3621- CONFIG_SYS_FLASH_QUIET_TEST
5568e613
SR
3622 If this option is defined, the common CFI flash doesn't
3623 print it's warning upon not recognized FLASH banks. This
3624 is useful, if some of the configured banks are only
3625 optionally available.
3626
9a042e9c
JVB
3627- CONFIG_FLASH_SHOW_PROGRESS
3628 If defined (must be an integer), print out countdown
3629 digits and dots. Recommended value: 45 (9..1) for 80
3630 column displays, 15 (3..1) for 40 column displays.
3631
352ef3f1
SR
3632- CONFIG_FLASH_VERIFY
3633 If defined, the content of the flash (destination) is compared
3634 against the source after the write operation. An error message
3635 will be printed when the contents are not identical.
3636 Please note that this option is useless in nearly all cases,
3637 since such flash programming errors usually are detected earlier
3638 while unprotecting/erasing/programming. Please only enable
3639 this option if you really know what you are doing.
3640
6d0f6bcf 3641- CONFIG_SYS_RX_ETH_BUFFER:
11ccc33f
MZ
3642 Defines the number of Ethernet receive buffers. On some
3643 Ethernet controllers it is recommended to set this value
53cf9435
SR
3644 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3645 buffers can be full shortly after enabling the interface
11ccc33f 3646 on high Ethernet traffic.
53cf9435
SR
3647 Defaults to 4 if not defined.
3648
ea882baf
WD
3649- CONFIG_ENV_MAX_ENTRIES
3650
071bc923
WD
3651 Maximum number of entries in the hash table that is used
3652 internally to store the environment settings. The default
3653 setting is supposed to be generous and should work in most
3654 cases. This setting can be used to tune behaviour; see
3655 lib/hashtable.c for details.
ea882baf 3656
2598090b
JH
3657- CONFIG_ENV_FLAGS_LIST_DEFAULT
3658- CONFIG_ENV_FLAGS_LIST_STATIC
1bce2aeb 3659 Enable validation of the values given to environment variables when
2598090b
JH
3660 calling env set. Variables can be restricted to only decimal,
3661 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3662 the variables can also be restricted to IP address or MAC address.
3663
3664 The format of the list is:
3665 type_attribute = [s|d|x|b|i|m]
267541f7
JH
3666 access_atribute = [a|r|o|c]
3667 attributes = type_attribute[access_atribute]
2598090b
JH
3668 entry = variable_name[:attributes]
3669 list = entry[,list]
3670
3671 The type attributes are:
3672 s - String (default)
3673 d - Decimal
3674 x - Hexadecimal
3675 b - Boolean ([1yYtT|0nNfF])
3676 i - IP address
3677 m - MAC address
3678
267541f7
JH
3679 The access attributes are:
3680 a - Any (default)
3681 r - Read-only
3682 o - Write-once
3683 c - Change-default
3684
2598090b
JH
3685 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3686 Define this to a list (string) to define the ".flags"
3687 envirnoment variable in the default or embedded environment.
3688
3689 - CONFIG_ENV_FLAGS_LIST_STATIC
3690 Define this to a list (string) to define validation that
3691 should be done if an entry is not found in the ".flags"
3692 environment variable. To override a setting in the static
3693 list, simply add an entry for the same variable name to the
3694 ".flags" variable.
3695
267541f7
JH
3696- CONFIG_ENV_ACCESS_IGNORE_FORCE
3697 If defined, don't allow the -f switch to env set override variable
3698 access flags.
3699
5c1a7ea6
SG
3700- CONFIG_SYS_GENERIC_BOARD
3701 This selects the architecture-generic board system instead of the
3702 architecture-specific board files. It is intended to move boards
3703 to this new framework over time. Defining this will disable the
3704 arch/foo/lib/board.c file and use common/board_f.c and
3705 common/board_r.c instead. To use this option your architecture
3706 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3707 its config.mk file). If you find problems enabling this option on
3708 your board please report the problem and send patches!
3709
0b1b60c7
LV
3710- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3711 This is set by OMAP boards for the max time that reset should
3712 be asserted. See doc/README.omap-reset-time for details on how
3713 the value can be calulated on a given board.
632efa74 3714
c609719b
WD
3715The following definitions that deal with the placement and management
3716of environment data (variable area); in general, we support the
3717following configurations:
3718
c3eb3fe4
MF
3719- CONFIG_BUILD_ENVCRC:
3720
3721 Builds up envcrc with the target environment so that external utils
3722 may easily extract it and embed it in final U-Boot images.
3723
5a1aceb0 3724- CONFIG_ENV_IS_IN_FLASH:
c609719b
WD
3725
3726 Define this if the environment is in flash memory.
3727
3728 a) The environment occupies one whole flash sector, which is
3729 "embedded" in the text segment with the U-Boot code. This
3730 happens usually with "bottom boot sector" or "top boot
3731 sector" type flash chips, which have several smaller
3732 sectors at the start or the end. For instance, such a
3733 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3734 such a case you would place the environment in one of the
3735 4 kB sectors - with U-Boot code before and after it. With
3736 "top boot sector" type flash chips, you would put the
3737 environment in one of the last sectors, leaving a gap
3738 between U-Boot and the environment.
3739
0e8d1586 3740 - CONFIG_ENV_OFFSET:
c609719b
WD
3741
3742 Offset of environment data (variable area) to the
3743 beginning of flash memory; for instance, with bottom boot
3744 type flash chips the second sector can be used: the offset
3745 for this sector is given here.
3746
6d0f6bcf 3747 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
c609719b 3748
0e8d1586 3749 - CONFIG_ENV_ADDR:
c609719b
WD
3750
3751 This is just another way to specify the start address of
3752 the flash sector containing the environment (instead of
0e8d1586 3753 CONFIG_ENV_OFFSET).
c609719b 3754
0e8d1586 3755 - CONFIG_ENV_SECT_SIZE:
c609719b
WD
3756
3757 Size of the sector containing the environment.
3758
3759
3760 b) Sometimes flash chips have few, equal sized, BIG sectors.
3761 In such a case you don't want to spend a whole sector for
3762 the environment.
3763
0e8d1586 3764 - CONFIG_ENV_SIZE:
c609719b 3765
5a1aceb0 3766 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
0e8d1586 3767 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
c609719b
WD
3768 of this flash sector for the environment. This saves
3769 memory for the RAM copy of the environment.
3770
3771 It may also save flash memory if you decide to use this
3772 when your environment is "embedded" within U-Boot code,
3773 since then the remainder of the flash sector could be used
3774 for U-Boot code. It should be pointed out that this is
3775 STRONGLY DISCOURAGED from a robustness point of view:
3776 updating the environment in flash makes it always
3777 necessary to erase the WHOLE sector. If something goes
3778 wrong before the contents has been restored from a copy in
3779 RAM, your target system will be dead.
3780
0e8d1586
JCPV
3781 - CONFIG_ENV_ADDR_REDUND
3782 CONFIG_ENV_SIZE_REDUND
c609719b 3783
43d9616c 3784 These settings describe a second storage area used to hold
11ccc33f 3785 a redundant copy of the environment data, so that there is
3e38691e 3786 a valid backup copy in case there is a power failure during
43d9616c 3787 a "saveenv" operation.
c609719b
WD
3788
3789BE CAREFUL! Any changes to the flash layout, and some changes to the
3790source code will make it necessary to adapt <board>/u-boot.lds*
3791accordingly!
3792
3793
9314cee6 3794- CONFIG_ENV_IS_IN_NVRAM:
c609719b
WD
3795
3796 Define this if you have some non-volatile memory device
3797 (NVRAM, battery buffered SRAM) which you want to use for the
3798 environment.
3799
0e8d1586
JCPV
3800 - CONFIG_ENV_ADDR:
3801 - CONFIG_ENV_SIZE:
c609719b 3802
11ccc33f 3803 These two #defines are used to determine the memory area you
c609719b
WD
3804 want to use for environment. It is assumed that this memory
3805 can just be read and written to, without any special
3806 provision.
3807
3808BE CAREFUL! The first access to the environment happens quite early
3809in U-Boot initalization (when we try to get the setting of for the
11ccc33f 3810console baudrate). You *MUST* have mapped your NVRAM area then, or
c609719b
WD
3811U-Boot will hang.
3812
3813Please note that even with NVRAM we still use a copy of the
3814environment in RAM: we could work on NVRAM directly, but we want to
3815keep settings there always unmodified except somebody uses "saveenv"
3816to save the current settings.
3817
3818
bb1f8b4f 3819- CONFIG_ENV_IS_IN_EEPROM:
c609719b
WD
3820
3821 Use this if you have an EEPROM or similar serial access
3822 device and a driver for it.
3823
0e8d1586
JCPV
3824 - CONFIG_ENV_OFFSET:
3825 - CONFIG_ENV_SIZE:
c609719b
WD
3826
3827 These two #defines specify the offset and size of the
3828 environment area within the total memory of your EEPROM.
3829
6d0f6bcf 3830 - CONFIG_SYS_I2C_EEPROM_ADDR:
c609719b
WD
3831 If defined, specified the chip address of the EEPROM device.
3832 The default address is zero.
3833
6d0f6bcf 3834 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
c609719b
WD
3835 If defined, the number of bits used to address bytes in a
3836 single page in the EEPROM device. A 64 byte page, for example
3837 would require six bits.
3838
6d0f6bcf 3839 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
c609719b 3840 If defined, the number of milliseconds to delay between
ba56f625 3841 page writes. The default is zero milliseconds.
c609719b 3842
6d0f6bcf 3843 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
c609719b
WD
3844 The length in bytes of the EEPROM memory array address. Note
3845 that this is NOT the chip address length!
3846
6d0f6bcf 3847 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
5cf91d6b
WD
3848 EEPROM chips that implement "address overflow" are ones
3849 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3850 address and the extra bits end up in the "chip address" bit
3851 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3852 byte chips.
3853
3854 Note that we consider the length of the address field to
3855 still be one byte because the extra address bits are hidden
3856 in the chip address.
3857
6d0f6bcf 3858 - CONFIG_SYS_EEPROM_SIZE:
c609719b
WD
3859 The size in bytes of the EEPROM device.
3860
548738b4
HS
3861 - CONFIG_ENV_EEPROM_IS_ON_I2C
3862 define this, if you have I2C and SPI activated, and your
3863 EEPROM, which holds the environment, is on the I2C bus.
3864
3865 - CONFIG_I2C_ENV_EEPROM_BUS
3866 if you have an Environment on an EEPROM reached over
3867 I2C muxes, you can define here, how to reach this
3868 EEPROM. For example:
3869
ea818dbb 3870 #define CONFIG_I2C_ENV_EEPROM_BUS 1
548738b4
HS
3871
3872 EEPROM which holds the environment, is reached over
3873 a pca9547 i2c mux with address 0x70, channel 3.
c609719b 3874
057c849c 3875- CONFIG_ENV_IS_IN_DATAFLASH:
5779d8d9 3876
d4ca31c4 3877 Define this if you have a DataFlash memory device which you
5779d8d9
WD
3878 want to use for the environment.
3879
0e8d1586
JCPV
3880 - CONFIG_ENV_OFFSET:
3881 - CONFIG_ENV_ADDR:
3882 - CONFIG_ENV_SIZE:
5779d8d9
WD
3883
3884 These three #defines specify the offset and size of the
3885 environment area within the total memory of your DataFlash placed
3886 at the specified address.
3887
0a85a9e7
LG
3888- CONFIG_ENV_IS_IN_REMOTE:
3889
3890 Define this if you have a remote memory space which you
3891 want to use for the local device's environment.
3892
3893 - CONFIG_ENV_ADDR:
3894 - CONFIG_ENV_SIZE:
3895
3896 These two #defines specify the address and size of the
3897 environment area within the remote memory space. The
3898 local device can get the environment from remote memory
fc54c7fa 3899 space by SRIO or PCIE links.
0a85a9e7
LG
3900
3901BE CAREFUL! For some special cases, the local device can not use
3902"saveenv" command. For example, the local device will get the
fc54c7fa
LG
3903environment stored in a remote NOR flash by SRIO or PCIE link,
3904but it can not erase, write this NOR flash by SRIO or PCIE interface.
0a85a9e7 3905
51bfee19 3906- CONFIG_ENV_IS_IN_NAND:
13a5695b
WD
3907
3908 Define this if you have a NAND device which you want to use
3909 for the environment.
3910
0e8d1586
JCPV
3911 - CONFIG_ENV_OFFSET:
3912 - CONFIG_ENV_SIZE:
13a5695b
WD
3913
3914 These two #defines specify the offset and size of the environment
fdd813de
SW
3915 area within the first NAND device. CONFIG_ENV_OFFSET must be
3916 aligned to an erase block boundary.
5779d8d9 3917
fdd813de 3918 - CONFIG_ENV_OFFSET_REDUND (optional):
e443c944 3919
0e8d1586 3920 This setting describes a second storage area of CONFIG_ENV_SIZE
fdd813de
SW
3921 size used to hold a redundant copy of the environment data, so
3922 that there is a valid backup copy in case there is a power failure
c0f40859 3923 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
fdd813de
SW
3924 aligned to an erase block boundary.
3925
3926 - CONFIG_ENV_RANGE (optional):
3927
3928 Specifies the length of the region in which the environment
3929 can be written. This should be a multiple of the NAND device's
3930 block size. Specifying a range with more erase blocks than
3931 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3932 the range to be avoided.
3933
3934 - CONFIG_ENV_OFFSET_OOB (optional):
3935
3936 Enables support for dynamically retrieving the offset of the
3937 environment from block zero's out-of-band data. The
3938 "nand env.oob" command can be used to record this offset.
3939 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3940 using CONFIG_ENV_OFFSET_OOB.
e443c944 3941
b74ab737
GL
3942- CONFIG_NAND_ENV_DST
3943
3944 Defines address in RAM to which the nand_spl code should copy the
3945 environment. If redundant environment is used, it will be copied to
3946 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3947
2b74433f
JH
3948- CONFIG_ENV_IS_IN_UBI:
3949
3950 Define this if you have an UBI volume that you want to use for the
3951 environment. This has the benefit of wear-leveling the environment
3952 accesses, which is important on NAND.
3953
3954 - CONFIG_ENV_UBI_PART:
3955
3956 Define this to a string that is the mtd partition containing the UBI.
3957
3958 - CONFIG_ENV_UBI_VOLUME:
3959
3960 Define this to the name of the volume that you want to store the
3961 environment in.
3962
785881f7
JH
3963 - CONFIG_ENV_UBI_VOLUME_REDUND:
3964
3965 Define this to the name of another volume to store a second copy of
3966 the environment in. This will enable redundant environments in UBI.
3967 It is assumed that both volumes are in the same MTD partition.
3968
2b74433f
JH
3969 - CONFIG_UBI_SILENCE_MSG
3970 - CONFIG_UBIFS_SILENCE_MSG
3971
3972 You will probably want to define these to avoid a really noisy system
3973 when storing the env in UBI.
3974
06e4ae5f
SW
3975- CONFIG_ENV_IS_IN_MMC:
3976
3977 Define this if you have an MMC device which you want to use for the
3978 environment.
3979
3980 - CONFIG_SYS_MMC_ENV_DEV:
3981
3982 Specifies which MMC device the environment is stored in.
3983
3984 - CONFIG_SYS_MMC_ENV_PART (optional):
3985
3986 Specifies which MMC partition the environment is stored in. If not
3987 set, defaults to partition 0, the user area. Common values might be
3988 1 (first MMC boot partition), 2 (second MMC boot partition).
3989
3990 - CONFIG_ENV_OFFSET:
3991 - CONFIG_ENV_SIZE:
3992
3993 These two #defines specify the offset and size of the environment
3994 area within the specified MMC device.
3995
5c088ee8
SW
3996 If offset is positive (the usual case), it is treated as relative to
3997 the start of the MMC partition. If offset is negative, it is treated
3998 as relative to the end of the MMC partition. This can be useful if
3999 your board may be fitted with different MMC devices, which have
4000 different sizes for the MMC partitions, and you always want the
4001 environment placed at the very end of the partition, to leave the
4002 maximum possible space before it, to store other data.
4003
06e4ae5f
SW
4004 These two values are in units of bytes, but must be aligned to an
4005 MMC sector boundary.
4006
4007 - CONFIG_ENV_OFFSET_REDUND (optional):
4008
4009 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4010 hold a redundant copy of the environment data. This provides a
4011 valid backup copy in case the other copy is corrupted, e.g. due
4012 to a power failure during a "saveenv" operation.
4013
5c088ee8
SW
4014 This value may also be positive or negative; this is handled in the
4015 same way as CONFIG_ENV_OFFSET.
4016
06e4ae5f
SW
4017 This value is also in units of bytes, but must also be aligned to
4018 an MMC sector boundary.
4019
4020 - CONFIG_ENV_SIZE_REDUND (optional):
4021
4022 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4023 set. If this value is set, it must be set to the same value as
4024 CONFIG_ENV_SIZE.
4025
6d0f6bcf 4026- CONFIG_SYS_SPI_INIT_OFFSET
c609719b
WD
4027
4028 Defines offset to the initial SPI buffer area in DPRAM. The
4029 area is used at an early stage (ROM part) if the environment
4030 is configured to reside in the SPI EEPROM: We need a 520 byte
4031 scratch DPRAM area. It is used between the two initialization
4032 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4033 to be a good choice since it makes it far enough from the
4034 start of the data area as well as from the stack pointer.
4035
e881cb56 4036Please note that the environment is read-only until the monitor
c609719b 4037has been relocated to RAM and a RAM copy of the environment has been
cdb74977 4038created; also, when using EEPROM you will have to use getenv_f()
c609719b
WD
4039until then to read environment variables.
4040
85ec0bcc
WD
4041The environment is protected by a CRC32 checksum. Before the monitor
4042is relocated into RAM, as a result of a bad CRC you will be working
4043with the compiled-in default environment - *silently*!!! [This is
4044necessary, because the first environment variable we need is the
4045"baudrate" setting for the console - if we have a bad CRC, we don't
4046have any device yet where we could complain.]
c609719b
WD
4047
4048Note: once the monitor has been relocated, then it will complain if
4049the default environment is used; a new CRC is computed as soon as you
85ec0bcc 4050use the "saveenv" command to store a valid environment.
c609719b 4051
6d0f6bcf 4052- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
42d1f039 4053 Echo the inverted Ethernet link state to the fault LED.
fc3e2165 4054
6d0f6bcf 4055 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
fc3e2165
WD
4056 also needs to be defined.
4057
6d0f6bcf 4058- CONFIG_SYS_FAULT_MII_ADDR:
42d1f039 4059 MII address of the PHY to check for the Ethernet link state.
c609719b 4060
f5675aa5
RM
4061- CONFIG_NS16550_MIN_FUNCTIONS:
4062 Define this if you desire to only have use of the NS16550_init
4063 and NS16550_putc functions for the serial driver located at
4064 drivers/serial/ns16550.c. This option is useful for saving
4065 space for already greatly restricted images, including but not
4066 limited to NAND_SPL configurations.
4067
b2b92f53
SG
4068- CONFIG_DISPLAY_BOARDINFO
4069 Display information about the board that U-Boot is running on
4070 when U-Boot starts up. The board function checkboard() is called
4071 to do this.
4072
e2e3e2b1
SG
4073- CONFIG_DISPLAY_BOARDINFO_LATE
4074 Similar to the previous option, but display this information
4075 later, once stdio is running and output goes to the LCD, if
4076 present.
4077
c609719b 4078Low Level (hardware related) configuration options:
dc7c9a1a 4079---------------------------------------------------
c609719b 4080
6d0f6bcf 4081- CONFIG_SYS_CACHELINE_SIZE:
c609719b
WD
4082 Cache Line Size of the CPU.
4083
6d0f6bcf 4084- CONFIG_SYS_DEFAULT_IMMR:
c609719b 4085 Default address of the IMMR after system reset.
2535d602 4086
42d1f039
WD
4087 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4088 and RPXsuper) to be able to adjust the position of
4089 the IMMR register after a reset.
c609719b 4090
e46fedfe
TT
4091- CONFIG_SYS_CCSRBAR_DEFAULT:
4092 Default (power-on reset) physical address of CCSR on Freescale
4093 PowerPC SOCs.
4094
4095- CONFIG_SYS_CCSRBAR:
4096 Virtual address of CCSR. On a 32-bit build, this is typically
4097 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4098
4099 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4100 for cross-platform code that uses that macro instead.
4101
4102- CONFIG_SYS_CCSRBAR_PHYS:
4103 Physical address of CCSR. CCSR can be relocated to a new
4104 physical address, if desired. In this case, this macro should
c0f40859 4105 be set to that address. Otherwise, it should be set to the
e46fedfe
TT
4106 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4107 is typically relocated on 36-bit builds. It is recommended
4108 that this macro be defined via the _HIGH and _LOW macros:
4109
4110 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4111 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4112
4113- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4cf2609b
WD
4114 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4115 either 0 (32-bit build) or 0xF (36-bit build). This macro is
e46fedfe
TT
4116 used in assembly code, so it must not contain typecasts or
4117 integer size suffixes (e.g. "ULL").
4118
4119- CONFIG_SYS_CCSRBAR_PHYS_LOW:
4120 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4121 used in assembly code, so it must not contain typecasts or
4122 integer size suffixes (e.g. "ULL").
4123
4124- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4125 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4126 forced to a value that ensures that CCSR is not relocated.
4127
7f6c2cbc 4128- Floppy Disk Support:
6d0f6bcf 4129 CONFIG_SYS_FDC_DRIVE_NUMBER
7f6c2cbc
WD
4130
4131 the default drive number (default value 0)
4132
6d0f6bcf 4133 CONFIG_SYS_ISA_IO_STRIDE
7f6c2cbc 4134
11ccc33f 4135 defines the spacing between FDC chipset registers
7f6c2cbc
WD
4136 (default value 1)
4137
6d0f6bcf 4138 CONFIG_SYS_ISA_IO_OFFSET
7f6c2cbc 4139
43d9616c
WD
4140 defines the offset of register from address. It
4141 depends on which part of the data bus is connected to
11ccc33f 4142 the FDC chipset. (default value 0)
7f6c2cbc 4143
6d0f6bcf
JCPV
4144 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4145 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
43d9616c 4146 default value.
7f6c2cbc 4147
6d0f6bcf 4148 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
43d9616c
WD
4149 fdc_hw_init() is called at the beginning of the FDC
4150 setup. fdc_hw_init() must be provided by the board
4151 source code. It is used to make hardware dependant
4152 initializations.
7f6c2cbc 4153
0abddf82
ML
4154- CONFIG_IDE_AHB:
4155 Most IDE controllers were designed to be connected with PCI
4156 interface. Only few of them were designed for AHB interface.
4157 When software is doing ATA command and data transfer to
4158 IDE devices through IDE-AHB controller, some additional
4159 registers accessing to these kind of IDE-AHB controller
4160 is requierd.
4161
6d0f6bcf 4162- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
efe2a4d5 4163 DO NOT CHANGE unless you know exactly what you're
25d6712a 4164 doing! (11-4) [MPC8xx/82xx systems only]
c609719b 4165
6d0f6bcf 4166- CONFIG_SYS_INIT_RAM_ADDR:
c609719b 4167
7152b1d0 4168 Start address of memory area that can be used for
c609719b
WD
4169 initial data and stack; please note that this must be
4170 writable memory that is working WITHOUT special
4171 initialization, i. e. you CANNOT use normal RAM which
4172 will become available only after programming the
4173 memory controller and running certain initialization
4174 sequences.
4175
4176 U-Boot uses the following memory types:
4177 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4178 - MPC824X: data cache
4179 - PPC4xx: data cache
4180
6d0f6bcf 4181- CONFIG_SYS_GBL_DATA_OFFSET:
c609719b
WD
4182
4183 Offset of the initial data structure in the memory
6d0f6bcf
JCPV
4184 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4185 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
c609719b 4186 data is located at the end of the available space
553f0982 4187 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
6d0f6bcf
JCPV
4188 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4189 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4190 CONFIG_SYS_GBL_DATA_OFFSET) downward.
c609719b
WD
4191
4192 Note:
4193 On the MPC824X (or other systems that use the data
4194 cache for initial memory) the address chosen for
6d0f6bcf 4195 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
c609719b
WD
4196 point to an otherwise UNUSED address space between
4197 the top of RAM and the start of the PCI space.
4198
6d0f6bcf 4199- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
c609719b 4200
6d0f6bcf 4201- CONFIG_SYS_SYPCR: System Protection Control (11-9)
c609719b 4202
6d0f6bcf 4203- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
c609719b 4204
6d0f6bcf 4205- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
c609719b 4206
6d0f6bcf 4207- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
c609719b 4208
6d0f6bcf 4209- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
c609719b 4210
6d0f6bcf 4211- CONFIG_SYS_OR_TIMING_SDRAM:
c609719b
WD
4212 SDRAM timing
4213
6d0f6bcf 4214- CONFIG_SYS_MAMR_PTA:
c609719b
WD
4215 periodic timer for refresh
4216
6d0f6bcf 4217- CONFIG_SYS_DER: Debug Event Register (37-47)
c609719b 4218
6d0f6bcf
JCPV
4219- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4220 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4221 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4222 CONFIG_SYS_BR1_PRELIM:
c609719b
WD
4223 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4224
4225- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
6d0f6bcf
JCPV
4226 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4227 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
c609719b
WD
4228 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4229
6d0f6bcf
JCPV
4230- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4231 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
c609719b
WD
4232 Machine Mode Register and Memory Periodic Timer
4233 Prescaler definitions (SDRAM timing)
4234
6d0f6bcf 4235- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
c609719b
WD
4236 enable I2C microcode relocation patch (MPC8xx);
4237 define relocation offset in DPRAM [DSP2]
4238
6d0f6bcf 4239- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
b423d055
HS
4240 enable SMC microcode relocation patch (MPC8xx);
4241 define relocation offset in DPRAM [SMC1]
4242
6d0f6bcf 4243- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
c609719b
WD
4244 enable SPI microcode relocation patch (MPC8xx);
4245 define relocation offset in DPRAM [SCC4]
4246
6d0f6bcf 4247- CONFIG_SYS_USE_OSCCLK:
c609719b
WD
4248 Use OSCM clock mode on MBX8xx board. Be careful,
4249 wrong setting might damage your board. Read
4250 doc/README.MBX before setting this variable!
4251
6d0f6bcf 4252- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
43d9616c
WD
4253 Offset of the bootmode word in DPRAM used by post
4254 (Power On Self Tests). This definition overrides
4255 #define'd default value in commproc.h resp.
4256 cpm_8260.h.
ea909b76 4257
6d0f6bcf
JCPV
4258- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4259 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4260 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4261 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4262 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4263 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4264 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4265 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
a47a12be 4266 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
5d232d0e 4267
9cacf4fc
DE
4268- CONFIG_PCI_DISABLE_PCIE:
4269 Disable PCI-Express on systems where it is supported but not
4270 required.
4271
69fd2d3b
AS
4272- CONFIG_PCI_ENUM_ONLY
4273 Only scan through and get the devices on the busses.
4274 Don't do any setup work, presumably because someone or
4275 something has already done it, and we don't need to do it
4276 a second time. Useful for platforms that are pre-booted
4277 by coreboot or similar.
4278
842033e6
GJ
4279- CONFIG_PCI_INDIRECT_BRIDGE:
4280 Enable support for indirect PCI bridges.
4281
a09b9b68
KG
4282- CONFIG_SYS_SRIO:
4283 Chip has SRIO or not
4284
4285- CONFIG_SRIO1:
4286 Board has SRIO 1 port available
4287
4288- CONFIG_SRIO2:
4289 Board has SRIO 2 port available
4290
c8b28152
LG
4291- CONFIG_SRIO_PCIE_BOOT_MASTER
4292 Board can support master function for Boot from SRIO and PCIE
4293
a09b9b68
KG
4294- CONFIG_SYS_SRIOn_MEM_VIRT:
4295 Virtual Address of SRIO port 'n' memory region
4296
4297- CONFIG_SYS_SRIOn_MEM_PHYS:
4298 Physical Address of SRIO port 'n' memory region
4299
4300- CONFIG_SYS_SRIOn_MEM_SIZE:
4301 Size of SRIO port 'n' memory region
4302
66bd1846
FE
4303- CONFIG_SYS_NAND_BUSWIDTH_16BIT
4304 Defined to tell the NAND controller that the NAND chip is using
4305 a 16 bit bus.
4306 Not all NAND drivers use this symbol.
a430e916 4307 Example of drivers that use it:
66bd1846 4308 - drivers/mtd/nand/ndfc.c
a430e916 4309 - drivers/mtd/nand/mxc_nand.c
eced4626
AW
4310
4311- CONFIG_SYS_NDFC_EBC0_CFG
4312 Sets the EBC0_CFG register for the NDFC. If not defined
4313 a default value will be used.
4314
bb99ad6d 4315- CONFIG_SPD_EEPROM
218ca724
WD
4316 Get DDR timing information from an I2C EEPROM. Common
4317 with pluggable memory modules such as SODIMMs
4318
bb99ad6d
BW
4319 SPD_EEPROM_ADDRESS
4320 I2C address of the SPD EEPROM
4321
6d0f6bcf 4322- CONFIG_SYS_SPD_BUS_NUM
218ca724
WD
4323 If SPD EEPROM is on an I2C bus other than the first
4324 one, specify here. Note that the value must resolve
4325 to something your driver can deal with.
bb99ad6d 4326
1b3e3c4f
YS
4327- CONFIG_SYS_DDR_RAW_TIMING
4328 Get DDR timing information from other than SPD. Common with
4329 soldered DDR chips onboard without SPD. DDR raw timing
4330 parameters are extracted from datasheet and hard-coded into
4331 header files or board specific files.
4332
6f5e1dc5
YS
4333- CONFIG_FSL_DDR_INTERACTIVE
4334 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4335
6d0f6bcf 4336- CONFIG_SYS_83XX_DDR_USES_CS0
218ca724
WD
4337 Only for 83xx systems. If specified, then DDR should
4338 be configured using CS0 and CS1 instead of CS2 and CS3.
2ad6b513 4339
c26e454d
WD
4340- CONFIG_ETHER_ON_FEC[12]
4341 Define to enable FEC[12] on a 8xx series processor.
4342
4343- CONFIG_FEC[12]_PHY
4344 Define to the hardcoded PHY address which corresponds
6e592385
WD
4345 to the given FEC; i. e.
4346 #define CONFIG_FEC1_PHY 4
c26e454d
WD
4347 means that the PHY with address 4 is connected to FEC1
4348
4349 When set to -1, means to probe for first available.
4350
4351- CONFIG_FEC[12]_PHY_NORXERR
4352 The PHY does not have a RXERR line (RMII only).
4353 (so program the FEC to ignore it).
4354
4355- CONFIG_RMII
4356 Enable RMII mode for all FECs.
4357 Note that this is a global option, we can't
4358 have one FEC in standard MII mode and another in RMII mode.
4359
5cf91d6b
WD
4360- CONFIG_CRC32_VERIFY
4361 Add a verify option to the crc32 command.
4362 The syntax is:
4363
4364 => crc32 -v <address> <count> <crc32>
4365
4366 Where address/count indicate a memory area
4367 and crc32 is the correct crc32 which the
4368 area should have.
4369
56523f12
WD
4370- CONFIG_LOOPW
4371 Add the "loopw" memory command. This only takes effect if
602ad3b3 4372 the memory commands are activated globally (CONFIG_CMD_MEM).
56523f12 4373
7b466641
SR
4374- CONFIG_MX_CYCLIC
4375 Add the "mdc" and "mwc" memory commands. These are cyclic
4376 "md/mw" commands.
4377 Examples:
4378
efe2a4d5 4379 => mdc.b 10 4 500
7b466641
SR
4380 This command will print 4 bytes (10,11,12,13) each 500 ms.
4381
efe2a4d5 4382 => mwc.l 100 12345678 10
7b466641
SR
4383 This command will write 12345678 to address 100 all 10 ms.
4384
efe2a4d5 4385 This only takes effect if the memory commands are activated
602ad3b3 4386 globally (CONFIG_CMD_MEM).
7b466641 4387
8aa1a2d1 4388- CONFIG_SKIP_LOWLEVEL_INIT
afc1ce82 4389 [ARM, NDS32, MIPS only] If this variable is defined, then certain
844f07d8
WD
4390 low level initializations (like setting up the memory
4391 controller) are omitted and/or U-Boot does not
4392 relocate itself into RAM.
4393
4394 Normally this variable MUST NOT be defined. The only
4395 exception is when U-Boot is loaded (to RAM) by some
4396 other boot loader or by a debugger which performs
4397 these initializations itself.
8aa1a2d1 4398
401bb30b 4399- CONFIG_SPL_BUILD
df81238b
ML
4400 Modifies the behaviour of start.S when compiling a loader
4401 that is executed before the actual U-Boot. E.g. when
4402 compiling a NAND SPL.
400558b5 4403
3aa29de0
YZ
4404- CONFIG_TPL_BUILD
4405 Modifies the behaviour of start.S when compiling a loader
4406 that is executed after the SPL and before the actual U-Boot.
4407 It is loaded by the SPL.
4408
5df572f0
YZ
4409- CONFIG_SYS_MPC85XX_NO_RESETVEC
4410 Only for 85xx systems. If this variable is specified, the section
4411 .resetvec is not kept and the section .bootpg is placed in the
4412 previous 4k of the .text section.
4413
4213fc29
SG
4414- CONFIG_ARCH_MAP_SYSMEM
4415 Generally U-Boot (and in particular the md command) uses
4416 effective address. It is therefore not necessary to regard
4417 U-Boot address as virtual addresses that need to be translated
4418 to physical addresses. However, sandbox requires this, since
4419 it maintains its own little RAM buffer which contains all
4420 addressable memory. This option causes some memory accesses
4421 to be mapped through map_sysmem() / unmap_sysmem().
4422
d8834a13
MW
4423- CONFIG_USE_ARCH_MEMCPY
4424 CONFIG_USE_ARCH_MEMSET
4425 If these options are used a optimized version of memcpy/memset will
4426 be used if available. These functions may be faster under some
4427 conditions but may increase the binary size.
4428
588a13f7
SG
4429- CONFIG_X86_RESET_VECTOR
4430 If defined, the x86 reset vector code is included. This is not
4431 needed when U-Boot is running from Coreboot.
b16f521a 4432
fc33705e
MJ
4433- CONFIG_SYS_MPUCLK
4434 Defines the MPU clock speed (in MHz).
4435
4436 NOTE : currently only supported on AM335x platforms.
5b5ece9e 4437
16678eb4
HS
4438- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4439 Enables the RTC32K OSC on AM33xx based plattforms
4440
f2717b47
TT
4441Freescale QE/FMAN Firmware Support:
4442-----------------------------------
4443
4444The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4445loading of "firmware", which is encoded in the QE firmware binary format.
4446This firmware often needs to be loaded during U-Boot booting, so macros
4447are used to identify the storage device (NOR flash, SPI, etc) and the address
4448within that device.
4449
4450- CONFIG_SYS_QE_FMAN_FW_ADDR
4451 The address in the storage device where the firmware is located. The
4452 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4453 is also specified.
4454
4455- CONFIG_SYS_QE_FMAN_FW_LENGTH
4456 The maximum possible size of the firmware. The firmware binary format
4457 has a field that specifies the actual size of the firmware, but it
4458 might not be possible to read any part of the firmware unless some
4459 local storage is allocated to hold the entire firmware first.
4460
4461- CONFIG_SYS_QE_FMAN_FW_IN_NOR
4462 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4463 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4464 virtual address in NOR flash.
4465
4466- CONFIG_SYS_QE_FMAN_FW_IN_NAND
4467 Specifies that QE/FMAN firmware is located in NAND flash.
4468 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4469
4470- CONFIG_SYS_QE_FMAN_FW_IN_MMC
4471 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4472 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4473
4474- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4475 Specifies that QE/FMAN firmware is located on the primary SPI
4476 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4477
292dc6c5
LG
4478- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4479 Specifies that QE/FMAN firmware is located in the remote (master)
4480 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
fc54c7fa
LG
4481 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4482 window->master inbound window->master LAW->the ucode address in
4483 master's memory space.
f2717b47 4484
c609719b
WD
4485Building the Software:
4486======================
4487
218ca724
WD
4488Building U-Boot has been tested in several native build environments
4489and in many different cross environments. Of course we cannot support
4490all possibly existing versions of cross development tools in all
4491(potentially obsolete) versions. In case of tool chain problems we
4492recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4493which is extensively used to build and test U-Boot.
c609719b 4494
218ca724
WD
4495If you are not using a native environment, it is assumed that you
4496have GNU cross compiling tools available in your path. In this case,
4497you must set the environment variable CROSS_COMPILE in your shell.
4498Note that no changes to the Makefile or any other source files are
4499necessary. For example using the ELDK on a 4xx CPU, please enter:
c609719b 4500
218ca724
WD
4501 $ CROSS_COMPILE=ppc_4xx-
4502 $ export CROSS_COMPILE
c609719b 4503
2f8d396b
PT
4504Note: If you wish to generate Windows versions of the utilities in
4505 the tools directory you can use the MinGW toolchain
4506 (http://www.mingw.org). Set your HOST tools to the MinGW
4507 toolchain and execute 'make tools'. For example:
4508
4509 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4510
4511 Binaries such as tools/mkimage.exe will be created which can
4512 be executed on computers running Windows.
4513
218ca724
WD
4514U-Boot is intended to be simple to build. After installing the
4515sources you must configure U-Boot for one specific board type. This
c609719b
WD
4516is done by typing:
4517
4518 make NAME_config
4519
218ca724 4520where "NAME_config" is the name of one of the existing configu-
4d675ae6 4521rations; see boards.cfg for supported names.
db01a2ea 4522
2729af9d
WD
4523Note: for some board special configuration names may exist; check if
4524 additional information is available from the board vendor; for
4525 instance, the TQM823L systems are available without (standard)
4526 or with LCD support. You can select such additional "features"
11ccc33f 4527 when choosing the configuration, i. e.
2729af9d
WD
4528
4529 make TQM823L_config
4530 - will configure for a plain TQM823L, i. e. no LCD support
4531
4532 make TQM823L_LCD_config
4533 - will configure for a TQM823L with U-Boot console on LCD
4534
4535 etc.
4536
4537
4538Finally, type "make all", and you should get some working U-Boot
4539images ready for download to / installation on your system:
4540
4541- "u-boot.bin" is a raw binary image
4542- "u-boot" is an image in ELF binary format
4543- "u-boot.srec" is in Motorola S-Record format
4544
baf31249
MB
4545By default the build is performed locally and the objects are saved
4546in the source directory. One of the two methods can be used to change
4547this behavior and build U-Boot to some external directory:
4548
45491. Add O= to the make command line invocations:
4550
4551 make O=/tmp/build distclean
4552 make O=/tmp/build NAME_config
4553 make O=/tmp/build all
4554
45552. Set environment variable BUILD_DIR to point to the desired location:
4556
4557 export BUILD_DIR=/tmp/build
4558 make distclean
4559 make NAME_config
4560 make all
4561
4562Note that the command line "O=" setting overrides the BUILD_DIR environment
4563variable.
4564
2729af9d
WD
4565
4566Please be aware that the Makefiles assume you are using GNU make, so
4567for instance on NetBSD you might need to use "gmake" instead of
4568native "make".
4569
4570
4571If the system board that you have is not listed, then you will need
4572to port U-Boot to your hardware platform. To do this, follow these
4573steps:
4574
45751. Add a new configuration option for your board to the toplevel
4d675ae6
MJ
4576 "boards.cfg" file, using the existing entries as examples.
4577 Follow the instructions there to keep the boards in order.
2729af9d
WD
45782. Create a new directory to hold your board specific code. Add any
4579 files you need. In your board directory, you will need at least
4580 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
45813. Create a new configuration file "include/configs/<board>.h" for
4582 your board
45833. If you're porting U-Boot to a new CPU, then also create a new
4584 directory to hold your CPU specific code. Add any files you need.
45854. Run "make <board>_config" with your new name.
45865. Type "make", and you should get a working "u-boot.srec" file
4587 to be installed on your target system.
45886. Debug and solve any problems that might arise.
4589 [Of course, this last step is much harder than it sounds.]
4590
4591
4592Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4593==============================================================
4594
218ca724
WD
4595If you have modified U-Boot sources (for instance added a new board
4596or support for new devices, a new CPU, etc.) you are expected to
2729af9d
WD
4597provide feedback to the other developers. The feedback normally takes
4598the form of a "patch", i. e. a context diff against a certain (latest
218ca724 4599official or latest in the git repository) version of U-Boot sources.
2729af9d 4600
218ca724
WD
4601But before you submit such a patch, please verify that your modifi-
4602cation did not break existing code. At least make sure that *ALL* of
2729af9d
WD
4603the supported boards compile WITHOUT ANY compiler warnings. To do so,
4604just run the "MAKEALL" script, which will configure and build U-Boot
218ca724
WD
4605for ALL supported system. Be warned, this will take a while. You can
4606select which (cross) compiler to use by passing a `CROSS_COMPILE'
4607environment variable to the script, i. e. to use the ELDK cross tools
4608you can type
2729af9d
WD
4609
4610 CROSS_COMPILE=ppc_8xx- MAKEALL
4611
4612or to build on a native PowerPC system you can type
4613
4614 CROSS_COMPILE=' ' MAKEALL
4615
218ca724
WD
4616When using the MAKEALL script, the default behaviour is to build
4617U-Boot in the source directory. This location can be changed by
4618setting the BUILD_DIR environment variable. Also, for each target
4619built, the MAKEALL script saves two log files (<target>.ERR and
4620<target>.MAKEALL) in the <source dir>/LOG directory. This default
4621location can be changed by setting the MAKEALL_LOGDIR environment
4622variable. For example:
baf31249
MB
4623
4624 export BUILD_DIR=/tmp/build
4625 export MAKEALL_LOGDIR=/tmp/log
4626 CROSS_COMPILE=ppc_8xx- MAKEALL
4627
218ca724
WD
4628With the above settings build objects are saved in the /tmp/build,
4629log files are saved in the /tmp/log and the source tree remains clean
4630during the whole build process.
baf31249
MB
4631
4632
2729af9d
WD
4633See also "U-Boot Porting Guide" below.
4634
4635
4636Monitor Commands - Overview:
4637============================
4638
4639go - start application at address 'addr'
4640run - run commands in an environment variable
4641bootm - boot application image from memory
4642bootp - boot image via network using BootP/TFTP protocol
44f074c7 4643bootz - boot zImage from memory
2729af9d
WD
4644tftpboot- boot image via network using TFTP protocol
4645 and env variables "ipaddr" and "serverip"
4646 (and eventually "gatewayip")
1fb7cd49 4647tftpput - upload a file via network using TFTP protocol
2729af9d
WD
4648rarpboot- boot image via network using RARP/TFTP protocol
4649diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4650loads - load S-Record file over serial line
4651loadb - load binary file over serial line (kermit mode)
4652md - memory display
4653mm - memory modify (auto-incrementing)
4654nm - memory modify (constant address)
4655mw - memory write (fill)
4656cp - memory copy
4657cmp - memory compare
4658crc32 - checksum calculation
0f89c54b 4659i2c - I2C sub-system
2729af9d
WD
4660sspi - SPI utility commands
4661base - print or set address offset
4662printenv- print environment variables
4663setenv - set environment variables
4664saveenv - save environment variables to persistent storage
4665protect - enable or disable FLASH write protection
4666erase - erase FLASH memory
4667flinfo - print FLASH memory information
10635afa 4668nand - NAND memory operations (see doc/README.nand)
2729af9d
WD
4669bdinfo - print Board Info structure
4670iminfo - print header information for application image
4671coninfo - print console devices and informations
4672ide - IDE sub-system
4673loop - infinite loop on address range
56523f12 4674loopw - infinite write loop on address range
2729af9d
WD
4675mtest - simple RAM test
4676icache - enable or disable instruction cache
4677dcache - enable or disable data cache
4678reset - Perform RESET of the CPU
4679echo - echo args to console
4680version - print monitor version
4681help - print online help
4682? - alias for 'help'
4683
4684
4685Monitor Commands - Detailed Description:
4686========================================
4687
4688TODO.
4689
4690For now: just type "help <command>".
4691
4692
4693Environment Variables:
4694======================
4695
4696U-Boot supports user configuration using Environment Variables which
4697can be made persistent by saving to Flash memory.
c609719b 4698
2729af9d
WD
4699Environment Variables are set using "setenv", printed using
4700"printenv", and saved to Flash using "saveenv". Using "setenv"
4701without a value can be used to delete a variable from the
4702environment. As long as you don't save the environment you are
4703working with an in-memory copy. In case the Flash area containing the
4704environment is erased by accident, a default environment is provided.
c609719b 4705
c96f86ee
WD
4706Some configuration options can be set using Environment Variables.
4707
4708List of environment variables (most likely not complete):
c609719b 4709
2729af9d 4710 baudrate - see CONFIG_BAUDRATE
c609719b 4711
2729af9d 4712 bootdelay - see CONFIG_BOOTDELAY
c609719b 4713
2729af9d 4714 bootcmd - see CONFIG_BOOTCOMMAND
4a6fd34b 4715
2729af9d 4716 bootargs - Boot arguments when booting an RTOS image
c609719b 4717
2729af9d 4718 bootfile - Name of the image to load with TFTP
c609719b 4719
7d721e34
BS
4720 bootm_low - Memory range available for image processing in the bootm
4721 command can be restricted. This variable is given as
4722 a hexadecimal number and defines lowest address allowed
4723 for use by the bootm command. See also "bootm_size"
4724 environment variable. Address defined by "bootm_low" is
4725 also the base of the initial memory mapping for the Linux
c3624e6e
GL
4726 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4727 bootm_mapsize.
4728
c0f40859 4729 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
c3624e6e
GL
4730 This variable is given as a hexadecimal number and it
4731 defines the size of the memory region starting at base
4732 address bootm_low that is accessible by the Linux kernel
4733 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4734 as the default value if it is defined, and bootm_size is
4735 used otherwise.
7d721e34
BS
4736
4737 bootm_size - Memory range available for image processing in the bootm
4738 command can be restricted. This variable is given as
4739 a hexadecimal number and defines the size of the region
4740 allowed for use by the bootm command. See also "bootm_low"
4741 environment variable.
4742
4bae9090
BS
4743 updatefile - Location of the software update file on a TFTP server, used
4744 by the automatic software update feature. Please refer to
4745 documentation in doc/README.update for more details.
4746
2729af9d
WD
4747 autoload - if set to "no" (any string beginning with 'n'),
4748 "bootp" will just load perform a lookup of the
4749 configuration from the BOOTP server, but not try to
4750 load any image using TFTP
c609719b 4751
2729af9d
WD
4752 autostart - if set to "yes", an image loaded using the "bootp",
4753 "rarpboot", "tftpboot" or "diskboot" commands will
4754 be automatically started (by internally calling
4755 "bootm")
38b99261 4756
2729af9d
WD
4757 If set to "no", a standalone image passed to the
4758 "bootm" command will be copied to the load address
4759 (and eventually uncompressed), but NOT be started.
4760 This can be used to load and uncompress arbitrary
4761 data.
c609719b 4762
a28afca5
DL
4763 fdt_high - if set this restricts the maximum address that the
4764 flattened device tree will be copied into upon boot.
fa34f6b2
SG
4765 For example, if you have a system with 1 GB memory
4766 at physical address 0x10000000, while Linux kernel
4767 only recognizes the first 704 MB as low memory, you
4768 may need to set fdt_high as 0x3C000000 to have the
4769 device tree blob be copied to the maximum address
4770 of the 704 MB low memory, so that Linux kernel can
4771 access it during the boot procedure.
4772
a28afca5
DL
4773 If this is set to the special value 0xFFFFFFFF then
4774 the fdt will not be copied at all on boot. For this
4775 to work it must reside in writable memory, have
4776 sufficient padding on the end of it for u-boot to
4777 add the information it needs into it, and the memory
4778 must be accessible by the kernel.
4779
eea63e05
SG
4780 fdtcontroladdr- if set this is the address of the control flattened
4781 device tree used by U-Boot when CONFIG_OF_CONTROL is
4782 defined.
4783
17ea1177
WD
4784 i2cfast - (PPC405GP|PPC405EP only)
4785 if set to 'y' configures Linux I2C driver for fast
4786 mode (400kHZ). This environment variable is used in
4787 initialization code. So, for changes to be effective
4788 it must be saved and board must be reset.
4789
2729af9d
WD
4790 initrd_high - restrict positioning of initrd images:
4791 If this variable is not set, initrd images will be
4792 copied to the highest possible address in RAM; this
4793 is usually what you want since it allows for
4794 maximum initrd size. If for some reason you want to
4795 make sure that the initrd image is loaded below the
6d0f6bcf 4796 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
2729af9d
WD
4797 variable to a value of "no" or "off" or "0".
4798 Alternatively, you can set it to a maximum upper
4799 address to use (U-Boot will still check that it
4800 does not overwrite the U-Boot stack and data).
c609719b 4801
2729af9d
WD
4802 For instance, when you have a system with 16 MB
4803 RAM, and want to reserve 4 MB from use by Linux,
4804 you can do this by adding "mem=12M" to the value of
4805 the "bootargs" variable. However, now you must make
4806 sure that the initrd image is placed in the first
4807 12 MB as well - this can be done with
c609719b 4808
2729af9d 4809 setenv initrd_high 00c00000
c609719b 4810
2729af9d
WD
4811 If you set initrd_high to 0xFFFFFFFF, this is an
4812 indication to U-Boot that all addresses are legal
4813 for the Linux kernel, including addresses in flash
4814 memory. In this case U-Boot will NOT COPY the
4815 ramdisk at all. This may be useful to reduce the
4816 boot time on your system, but requires that this
4817 feature is supported by your Linux kernel.
c609719b 4818
2729af9d 4819 ipaddr - IP address; needed for tftpboot command
c609719b 4820
2729af9d
WD
4821 loadaddr - Default load address for commands like "bootp",
4822 "rarpboot", "tftpboot", "loadb" or "diskboot"
c609719b 4823
2729af9d 4824 loads_echo - see CONFIG_LOADS_ECHO
a3d991bd 4825
2729af9d 4826 serverip - TFTP server IP address; needed for tftpboot command
a3d991bd 4827
2729af9d 4828 bootretry - see CONFIG_BOOT_RETRY_TIME
a3d991bd 4829
2729af9d 4830 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
a3d991bd 4831
2729af9d 4832 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
c609719b 4833
e2a53458 4834 ethprime - controls which interface is used first.
c609719b 4835
e2a53458
MF
4836 ethact - controls which interface is currently active.
4837 For example you can do the following
c609719b 4838
48690d80
HS
4839 => setenv ethact FEC
4840 => ping 192.168.0.1 # traffic sent on FEC
4841 => setenv ethact SCC
4842 => ping 10.0.0.1 # traffic sent on SCC
c609719b 4843
e1692577
MF
4844 ethrotate - When set to "no" U-Boot does not go through all
4845 available network interfaces.
4846 It just stays at the currently selected interface.
4847
c96f86ee 4848 netretry - When set to "no" each network operation will
2729af9d
WD
4849 either succeed or fail without retrying.
4850 When set to "once" the network operation will
4851 fail when all the available network interfaces
4852 are tried once without success.
4853 Useful on scripts which control the retry operation
4854 themselves.
c609719b 4855
b4e2f89d 4856 npe_ucode - set load address for the NPE microcode
a1cf027a 4857
8d51aacd
SG
4858 silent_linux - If set then linux will be told to boot silently, by
4859 changing the console to be empty. If "yes" it will be
4860 made silent. If "no" it will not be made silent. If
4861 unset, then it will be made silent if the U-Boot console
4862 is silent.
4863
28cb9375 4864 tftpsrcport - If this is set, the value is used for TFTP's
ecb0ccd9
WD
4865 UDP source port.
4866
28cb9375
WD
4867 tftpdstport - If this is set, the value is used for TFTP's UDP
4868 destination port instead of the Well Know Port 69.
4869
c96f86ee
WD
4870 tftpblocksize - Block size to use for TFTP transfers; if not set,
4871 we use the TFTP server's default block size
4872
4873 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4874 seconds, minimum value is 1000 = 1 second). Defines
4875 when a packet is considered to be lost so it has to
4876 be retransmitted. The default is 5000 = 5 seconds.
4877 Lowering this value may make downloads succeed
4878 faster in networks with high packet loss rates or
4879 with unreliable TFTP servers.
4880
4881 vlan - When set to a value < 4095 the traffic over
11ccc33f 4882 Ethernet is encapsulated/received over 802.1q
2729af9d 4883 VLAN tagged frames.
c609719b 4884
dc0b7b0e
JH
4885The following image location variables contain the location of images
4886used in booting. The "Image" column gives the role of the image and is
4887not an environment variable name. The other columns are environment
4888variable names. "File Name" gives the name of the file on a TFTP
4889server, "RAM Address" gives the location in RAM the image will be
4890loaded to, and "Flash Location" gives the image's address in NOR
4891flash or offset in NAND flash.
4892
4893*Note* - these variables don't have to be defined for all boards, some
4894boards currenlty use other variables for these purposes, and some
4895boards use these variables for other purposes.
4896
c0f40859
WD
4897Image File Name RAM Address Flash Location
4898----- --------- ----------- --------------
4899u-boot u-boot u-boot_addr_r u-boot_addr
4900Linux kernel bootfile kernel_addr_r kernel_addr
4901device tree blob fdtfile fdt_addr_r fdt_addr
4902ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
dc0b7b0e 4903
2729af9d
WD
4904The following environment variables may be used and automatically
4905updated by the network boot commands ("bootp" and "rarpboot"),
4906depending the information provided by your boot server:
c609719b 4907
2729af9d
WD
4908 bootfile - see above
4909 dnsip - IP address of your Domain Name Server
4910 dnsip2 - IP address of your secondary Domain Name Server
4911 gatewayip - IP address of the Gateway (Router) to use
4912 hostname - Target hostname
4913 ipaddr - see above
4914 netmask - Subnet Mask
4915 rootpath - Pathname of the root filesystem on the NFS server
4916 serverip - see above
c1551ea8 4917
c1551ea8 4918
2729af9d 4919There are two special Environment Variables:
c1551ea8 4920
2729af9d
WD
4921 serial# - contains hardware identification information such
4922 as type string and/or serial number
4923 ethaddr - Ethernet address
c609719b 4924
2729af9d
WD
4925These variables can be set only once (usually during manufacturing of
4926the board). U-Boot refuses to delete or overwrite these variables
4927once they have been set once.
c609719b 4928
f07771cc 4929
2729af9d 4930Further special Environment Variables:
f07771cc 4931
2729af9d
WD
4932 ver - Contains the U-Boot version string as printed
4933 with the "version" command. This variable is
4934 readonly (see CONFIG_VERSION_VARIABLE).
f07771cc 4935
f07771cc 4936
2729af9d
WD
4937Please note that changes to some configuration parameters may take
4938only effect after the next boot (yes, that's just like Windoze :-).
f07771cc 4939
f07771cc 4940
170ab110
JH
4941Callback functions for environment variables:
4942---------------------------------------------
4943
4944For some environment variables, the behavior of u-boot needs to change
4945when their values are changed. This functionailty allows functions to
4946be associated with arbitrary variables. On creation, overwrite, or
4947deletion, the callback will provide the opportunity for some side
4948effect to happen or for the change to be rejected.
4949
4950The callbacks are named and associated with a function using the
4951U_BOOT_ENV_CALLBACK macro in your board or driver code.
4952
4953These callbacks are associated with variables in one of two ways. The
4954static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4955in the board configuration to a string that defines a list of
4956associations. The list must be in the following format:
4957
4958 entry = variable_name[:callback_name]
4959 list = entry[,list]
4960
4961If the callback name is not specified, then the callback is deleted.
4962Spaces are also allowed anywhere in the list.
4963
4964Callbacks can also be associated by defining the ".callbacks" variable
4965with the same list format above. Any association in ".callbacks" will
4966override any association in the static list. You can define
4967CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4968".callbacks" envirnoment variable in the default or embedded environment.
4969
4970
2729af9d
WD
4971Command Line Parsing:
4972=====================
f07771cc 4973
2729af9d
WD
4974There are two different command line parsers available with U-Boot:
4975the old "simple" one, and the much more powerful "hush" shell:
c609719b 4976
2729af9d
WD
4977Old, simple command line parser:
4978--------------------------------
c609719b 4979
2729af9d
WD
4980- supports environment variables (through setenv / saveenv commands)
4981- several commands on one line, separated by ';'
fe126d8b 4982- variable substitution using "... ${name} ..." syntax
2729af9d
WD
4983- special characters ('$', ';') can be escaped by prefixing with '\',
4984 for example:
fe126d8b 4985 setenv bootcmd bootm \${address}
2729af9d
WD
4986- You can also escape text by enclosing in single apostrophes, for example:
4987 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
c609719b 4988
2729af9d
WD
4989Hush shell:
4990-----------
c609719b 4991
2729af9d
WD
4992- similar to Bourne shell, with control structures like
4993 if...then...else...fi, for...do...done; while...do...done,
4994 until...do...done, ...
4995- supports environment ("global") variables (through setenv / saveenv
4996 commands) and local shell variables (through standard shell syntax
4997 "name=value"); only environment variables can be used with "run"
4998 command
4999
5000General rules:
5001--------------
c609719b 5002
2729af9d
WD
5003(1) If a command line (or an environment variable executed by a "run"
5004 command) contains several commands separated by semicolon, and
5005 one of these commands fails, then the remaining commands will be
5006 executed anyway.
c609719b 5007
2729af9d 5008(2) If you execute several variables with one call to run (i. e.
11ccc33f 5009 calling run with a list of variables as arguments), any failing
2729af9d
WD
5010 command will cause "run" to terminate, i. e. the remaining
5011 variables are not executed.
c609719b 5012
2729af9d
WD
5013Note for Redundant Ethernet Interfaces:
5014=======================================
c609719b 5015
11ccc33f 5016Some boards come with redundant Ethernet interfaces; U-Boot supports
2729af9d
WD
5017such configurations and is capable of automatic selection of a
5018"working" interface when needed. MAC assignment works as follows:
c609719b 5019
2729af9d
WD
5020Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5021MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5022"eth1addr" (=>eth1), "eth2addr", ...
c609719b 5023
2729af9d
WD
5024If the network interface stores some valid MAC address (for instance
5025in SROM), this is used as default address if there is NO correspon-
5026ding setting in the environment; if the corresponding environment
5027variable is set, this overrides the settings in the card; that means:
c609719b 5028
2729af9d
WD
5029o If the SROM has a valid MAC address, and there is no address in the
5030 environment, the SROM's address is used.
c609719b 5031
2729af9d
WD
5032o If there is no valid address in the SROM, and a definition in the
5033 environment exists, then the value from the environment variable is
5034 used.
c609719b 5035
2729af9d
WD
5036o If both the SROM and the environment contain a MAC address, and
5037 both addresses are the same, this MAC address is used.
c609719b 5038
2729af9d
WD
5039o If both the SROM and the environment contain a MAC address, and the
5040 addresses differ, the value from the environment is used and a
5041 warning is printed.
c609719b 5042
2729af9d
WD
5043o If neither SROM nor the environment contain a MAC address, an error
5044 is raised.
c609719b 5045
ecee9324 5046If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
c0f40859 5047will be programmed into hardware as part of the initialization process. This
ecee9324
BW
5048may be skipped by setting the appropriate 'ethmacskip' environment variable.
5049The naming convention is as follows:
5050"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
c609719b 5051
2729af9d
WD
5052Image Formats:
5053==============
c609719b 5054
3310c549
MB
5055U-Boot is capable of booting (and performing other auxiliary operations on)
5056images in two formats:
5057
5058New uImage format (FIT)
5059-----------------------
5060
5061Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5062to Flattened Device Tree). It allows the use of images with multiple
5063components (several kernels, ramdisks, etc.), with contents protected by
5064SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5065
5066
5067Old uImage format
5068-----------------
5069
5070Old image format is based on binary files which can be basically anything,
5071preceded by a special header; see the definitions in include/image.h for
5072details; basically, the header defines the following image properties:
c609719b 5073
2729af9d
WD
5074* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5075 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
f5ed9e39
PT
5076 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5077 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5078 INTEGRITY).
7b64fef3 5079* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
afc1ce82
ML
5080 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5081 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
2729af9d
WD
5082* Compression Type (uncompressed, gzip, bzip2)
5083* Load Address
5084* Entry Point
5085* Image Name
5086* Image Timestamp
c609719b 5087
2729af9d
WD
5088The header is marked by a special Magic Number, and both the header
5089and the data portions of the image are secured against corruption by
5090CRC32 checksums.
c609719b
WD
5091
5092
2729af9d
WD
5093Linux Support:
5094==============
c609719b 5095
2729af9d
WD
5096Although U-Boot should support any OS or standalone application
5097easily, the main focus has always been on Linux during the design of
5098U-Boot.
c609719b 5099
2729af9d
WD
5100U-Boot includes many features that so far have been part of some
5101special "boot loader" code within the Linux kernel. Also, any
5102"initrd" images to be used are no longer part of one big Linux image;
5103instead, kernel and "initrd" are separate images. This implementation
5104serves several purposes:
c609719b 5105
2729af9d
WD
5106- the same features can be used for other OS or standalone
5107 applications (for instance: using compressed images to reduce the
5108 Flash memory footprint)
c609719b 5109
2729af9d
WD
5110- it becomes much easier to port new Linux kernel versions because
5111 lots of low-level, hardware dependent stuff are done by U-Boot
c609719b 5112
2729af9d
WD
5113- the same Linux kernel image can now be used with different "initrd"
5114 images; of course this also means that different kernel images can
5115 be run with the same "initrd". This makes testing easier (you don't
5116 have to build a new "zImage.initrd" Linux image when you just
5117 change a file in your "initrd"). Also, a field-upgrade of the
5118 software is easier now.
c609719b 5119
c609719b 5120
2729af9d
WD
5121Linux HOWTO:
5122============
c609719b 5123
2729af9d
WD
5124Porting Linux to U-Boot based systems:
5125---------------------------------------
c609719b 5126
2729af9d
WD
5127U-Boot cannot save you from doing all the necessary modifications to
5128configure the Linux device drivers for use with your target hardware
5129(no, we don't intend to provide a full virtual machine interface to
5130Linux :-).
c609719b 5131
a47a12be 5132But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
24ee89b9 5133
2729af9d
WD
5134Just make sure your machine specific header file (for instance
5135include/asm-ppc/tqm8xx.h) includes the same definition of the Board
1dc30693
MH
5136Information structure as we define in include/asm-<arch>/u-boot.h,
5137and make sure that your definition of IMAP_ADDR uses the same value
6d0f6bcf 5138as your U-Boot configuration in CONFIG_SYS_IMMR.
24ee89b9 5139
c609719b 5140
2729af9d
WD
5141Configuring the Linux kernel:
5142-----------------------------
c609719b 5143
2729af9d
WD
5144No specific requirements for U-Boot. Make sure you have some root
5145device (initial ramdisk, NFS) for your target system.
5146
5147
5148Building a Linux Image:
5149-----------------------
c609719b 5150
2729af9d
WD
5151With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5152not used. If you use recent kernel source, a new build target
5153"uImage" will exist which automatically builds an image usable by
5154U-Boot. Most older kernels also have support for a "pImage" target,
5155which was introduced for our predecessor project PPCBoot and uses a
5156100% compatible format.
5157
5158Example:
5159
5160 make TQM850L_config
5161 make oldconfig
5162 make dep
5163 make uImage
5164
5165The "uImage" build target uses a special tool (in 'tools/mkimage') to
5166encapsulate a compressed Linux kernel image with header information,
5167CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5168
5169* build a standard "vmlinux" kernel image (in ELF binary format):
5170
5171* convert the kernel into a raw binary image:
5172
5173 ${CROSS_COMPILE}-objcopy -O binary \
5174 -R .note -R .comment \
5175 -S vmlinux linux.bin
5176
5177* compress the binary image:
5178
5179 gzip -9 linux.bin
5180
5181* package compressed binary image for U-Boot:
5182
5183 mkimage -A ppc -O linux -T kernel -C gzip \
5184 -a 0 -e 0 -n "Linux Kernel Image" \
5185 -d linux.bin.gz uImage
c609719b 5186
c609719b 5187
2729af9d
WD
5188The "mkimage" tool can also be used to create ramdisk images for use
5189with U-Boot, either separated from the Linux kernel image, or
5190combined into one file. "mkimage" encapsulates the images with a 64
5191byte header containing information about target architecture,
5192operating system, image type, compression method, entry points, time
5193stamp, CRC32 checksums, etc.
5194
5195"mkimage" can be called in two ways: to verify existing images and
5196print the header information, or to build new images.
5197
5198In the first form (with "-l" option) mkimage lists the information
5199contained in the header of an existing U-Boot image; this includes
5200checksum verification:
c609719b 5201
2729af9d
WD
5202 tools/mkimage -l image
5203 -l ==> list image header information
5204
5205The second form (with "-d" option) is used to build a U-Boot image
5206from a "data file" which is used as image payload:
5207
5208 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5209 -n name -d data_file image
5210 -A ==> set architecture to 'arch'
5211 -O ==> set operating system to 'os'
5212 -T ==> set image type to 'type'
5213 -C ==> set compression type 'comp'
5214 -a ==> set load address to 'addr' (hex)
5215 -e ==> set entry point to 'ep' (hex)
5216 -n ==> set image name to 'name'
5217 -d ==> use image data from 'datafile'
5218
69459791
WD
5219Right now, all Linux kernels for PowerPC systems use the same load
5220address (0x00000000), but the entry point address depends on the
5221kernel version:
2729af9d
WD
5222
5223- 2.2.x kernels have the entry point at 0x0000000C,
5224- 2.3.x and later kernels have the entry point at 0x00000000.
5225
5226So a typical call to build a U-Boot image would read:
5227
5228 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5229 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
a47a12be 5230 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
2729af9d
WD
5231 > examples/uImage.TQM850L
5232 Image Name: 2.4.4 kernel for TQM850L
5233 Created: Wed Jul 19 02:34:59 2000
5234 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5235 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5236 Load Address: 0x00000000
5237 Entry Point: 0x00000000
5238
5239To verify the contents of the image (or check for corruption):
5240
5241 -> tools/mkimage -l examples/uImage.TQM850L
5242 Image Name: 2.4.4 kernel for TQM850L
5243 Created: Wed Jul 19 02:34:59 2000
5244 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5245 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5246 Load Address: 0x00000000
5247 Entry Point: 0x00000000
5248
5249NOTE: for embedded systems where boot time is critical you can trade
5250speed for memory and install an UNCOMPRESSED image instead: this
5251needs more space in Flash, but boots much faster since it does not
5252need to be uncompressed:
5253
a47a12be 5254 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
2729af9d
WD
5255 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5256 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
a47a12be 5257 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
2729af9d
WD
5258 > examples/uImage.TQM850L-uncompressed
5259 Image Name: 2.4.4 kernel for TQM850L
5260 Created: Wed Jul 19 02:34:59 2000
5261 Image Type: PowerPC Linux Kernel Image (uncompressed)
5262 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5263 Load Address: 0x00000000
5264 Entry Point: 0x00000000
5265
5266
5267Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5268when your kernel is intended to use an initial ramdisk:
5269
5270 -> tools/mkimage -n 'Simple Ramdisk Image' \
5271 > -A ppc -O linux -T ramdisk -C gzip \
5272 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5273 Image Name: Simple Ramdisk Image
5274 Created: Wed Jan 12 14:01:50 2000
5275 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5276 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5277 Load Address: 0x00000000
5278 Entry Point: 0x00000000
5279
a804b5ce
GMF
5280The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5281option performs the converse operation of the mkimage's second form (the "-d"
5282option). Given an image built by mkimage, the dumpimage extracts a "data file"
5283from the image:
5284
5285 tools/dumpimage -i image -p position data_file
5286 -i ==> extract from the 'image' a specific 'data_file', \
5287 indexed by 'position'
5288
2729af9d
WD
5289
5290Installing a Linux Image:
5291-------------------------
5292
5293To downloading a U-Boot image over the serial (console) interface,
5294you must convert the image to S-Record format:
5295
5296 objcopy -I binary -O srec examples/image examples/image.srec
5297
5298The 'objcopy' does not understand the information in the U-Boot
5299image header, so the resulting S-Record file will be relative to
5300address 0x00000000. To load it to a given address, you need to
5301specify the target address as 'offset' parameter with the 'loads'
5302command.
5303
5304Example: install the image to address 0x40100000 (which on the
5305TQM8xxL is in the first Flash bank):
5306
5307 => erase 40100000 401FFFFF
5308
5309 .......... done
5310 Erased 8 sectors
5311
5312 => loads 40100000
5313 ## Ready for S-Record download ...
5314 ~>examples/image.srec
5315 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5316 ...
5317 15989 15990 15991 15992
5318 [file transfer complete]
5319 [connected]
5320 ## Start Addr = 0x00000000
5321
5322
5323You can check the success of the download using the 'iminfo' command;
218ca724 5324this includes a checksum verification so you can be sure no data
2729af9d
WD
5325corruption happened:
5326
5327 => imi 40100000
5328
5329 ## Checking Image at 40100000 ...
5330 Image Name: 2.2.13 for initrd on TQM850L
5331 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5332 Data Size: 335725 Bytes = 327 kB = 0 MB
5333 Load Address: 00000000
5334 Entry Point: 0000000c
5335 Verifying Checksum ... OK
5336
5337
5338Boot Linux:
5339-----------
5340
5341The "bootm" command is used to boot an application that is stored in
5342memory (RAM or Flash). In case of a Linux kernel image, the contents
5343of the "bootargs" environment variable is passed to the kernel as
5344parameters. You can check and modify this variable using the
5345"printenv" and "setenv" commands:
5346
5347
5348 => printenv bootargs
5349 bootargs=root=/dev/ram
5350
5351 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5352
5353 => printenv bootargs
5354 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5355
5356 => bootm 40020000
5357 ## Booting Linux kernel at 40020000 ...
5358 Image Name: 2.2.13 for NFS on TQM850L
5359 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5360 Data Size: 381681 Bytes = 372 kB = 0 MB
5361 Load Address: 00000000
5362 Entry Point: 0000000c
5363 Verifying Checksum ... OK
5364 Uncompressing Kernel Image ... OK
5365 Linux version 2.2.13 ([email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
5366 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5367 time_init: decrementer frequency = 187500000/60
5368 Calibrating delay loop... 49.77 BogoMIPS
5369 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5370 ...
5371
11ccc33f 5372If you want to boot a Linux kernel with initial RAM disk, you pass
2729af9d
WD
5373the memory addresses of both the kernel and the initrd image (PPBCOOT
5374format!) to the "bootm" command:
5375
5376 => imi 40100000 40200000
5377
5378 ## Checking Image at 40100000 ...
5379 Image Name: 2.2.13 for initrd on TQM850L
5380 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5381 Data Size: 335725 Bytes = 327 kB = 0 MB
5382 Load Address: 00000000
5383 Entry Point: 0000000c
5384 Verifying Checksum ... OK
5385
5386 ## Checking Image at 40200000 ...
5387 Image Name: Simple Ramdisk Image
5388 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5389 Data Size: 566530 Bytes = 553 kB = 0 MB
5390 Load Address: 00000000
5391 Entry Point: 00000000
5392 Verifying Checksum ... OK
5393
5394 => bootm 40100000 40200000
5395 ## Booting Linux kernel at 40100000 ...
5396 Image Name: 2.2.13 for initrd on TQM850L
5397 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5398 Data Size: 335725 Bytes = 327 kB = 0 MB
5399 Load Address: 00000000
5400 Entry Point: 0000000c
5401 Verifying Checksum ... OK
5402 Uncompressing Kernel Image ... OK
5403 ## Loading RAMDisk Image at 40200000 ...
5404 Image Name: Simple Ramdisk Image
5405 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5406 Data Size: 566530 Bytes = 553 kB = 0 MB
5407 Load Address: 00000000
5408 Entry Point: 00000000
5409 Verifying Checksum ... OK
5410 Loading Ramdisk ... OK
5411 Linux version 2.2.13 ([email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
5412 Boot arguments: root=/dev/ram
5413 time_init: decrementer frequency = 187500000/60
5414 Calibrating delay loop... 49.77 BogoMIPS
5415 ...
5416 RAMDISK: Compressed image found at block 0
5417 VFS: Mounted root (ext2 filesystem).
5418
5419 bash#
5420
0267768e
MM
5421Boot Linux and pass a flat device tree:
5422-----------
5423
5424First, U-Boot must be compiled with the appropriate defines. See the section
5425titled "Linux Kernel Interface" above for a more in depth explanation. The
5426following is an example of how to start a kernel and pass an updated
5427flat device tree:
5428
5429=> print oftaddr
5430oftaddr=0x300000
5431=> print oft
5432oft=oftrees/mpc8540ads.dtb
5433=> tftp $oftaddr $oft
5434Speed: 1000, full duplex
5435Using TSEC0 device
5436TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5437Filename 'oftrees/mpc8540ads.dtb'.
5438Load address: 0x300000
5439Loading: #
5440done
5441Bytes transferred = 4106 (100a hex)
5442=> tftp $loadaddr $bootfile
5443Speed: 1000, full duplex
5444Using TSEC0 device
5445TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5446Filename 'uImage'.
5447Load address: 0x200000
5448Loading:############
5449done
5450Bytes transferred = 1029407 (fb51f hex)
5451=> print loadaddr
5452loadaddr=200000
5453=> print oftaddr
5454oftaddr=0x300000
5455=> bootm $loadaddr - $oftaddr
5456## Booting image at 00200000 ...
a9398e01
WD
5457 Image Name: Linux-2.6.17-dirty
5458 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5459 Data Size: 1029343 Bytes = 1005.2 kB
0267768e 5460 Load Address: 00000000
a9398e01 5461 Entry Point: 00000000
0267768e
MM
5462 Verifying Checksum ... OK
5463 Uncompressing Kernel Image ... OK
5464Booting using flat device tree at 0x300000
5465Using MPC85xx ADS machine description
5466Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5467[snip]
5468
5469
2729af9d
WD
5470More About U-Boot Image Types:
5471------------------------------
5472
5473U-Boot supports the following image types:
5474
5475 "Standalone Programs" are directly runnable in the environment
5476 provided by U-Boot; it is expected that (if they behave
5477 well) you can continue to work in U-Boot after return from
5478 the Standalone Program.
5479 "OS Kernel Images" are usually images of some Embedded OS which
5480 will take over control completely. Usually these programs
5481 will install their own set of exception handlers, device
5482 drivers, set up the MMU, etc. - this means, that you cannot
5483 expect to re-enter U-Boot except by resetting the CPU.
5484 "RAMDisk Images" are more or less just data blocks, and their
5485 parameters (address, size) are passed to an OS kernel that is
5486 being started.
5487 "Multi-File Images" contain several images, typically an OS
5488 (Linux) kernel image and one or more data images like
5489 RAMDisks. This construct is useful for instance when you want
5490 to boot over the network using BOOTP etc., where the boot
5491 server provides just a single image file, but you want to get
5492 for instance an OS kernel and a RAMDisk image.
5493
5494 "Multi-File Images" start with a list of image sizes, each
5495 image size (in bytes) specified by an "uint32_t" in network
5496 byte order. This list is terminated by an "(uint32_t)0".
5497 Immediately after the terminating 0 follow the images, one by
5498 one, all aligned on "uint32_t" boundaries (size rounded up to
5499 a multiple of 4 bytes).
5500
5501 "Firmware Images" are binary images containing firmware (like
5502 U-Boot or FPGA images) which usually will be programmed to
5503 flash memory.
5504
5505 "Script files" are command sequences that will be executed by
5506 U-Boot's command interpreter; this feature is especially
5507 useful when you configure U-Boot to use a real shell (hush)
5508 as command interpreter.
5509
44f074c7
MV
5510Booting the Linux zImage:
5511-------------------------
5512
5513On some platforms, it's possible to boot Linux zImage. This is done
5514using the "bootz" command. The syntax of "bootz" command is the same
5515as the syntax of "bootm" command.
5516
8ac28563 5517Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
017e1f3f
MV
5518kernel with raw initrd images. The syntax is slightly different, the
5519address of the initrd must be augmented by it's size, in the following
5520format: "<initrd addres>:<initrd size>".
5521
2729af9d
WD
5522
5523Standalone HOWTO:
5524=================
5525
5526One of the features of U-Boot is that you can dynamically load and
5527run "standalone" applications, which can use some resources of
5528U-Boot like console I/O functions or interrupt services.
5529
5530Two simple examples are included with the sources:
5531
5532"Hello World" Demo:
5533-------------------
5534
5535'examples/hello_world.c' contains a small "Hello World" Demo
5536application; it is automatically compiled when you build U-Boot.
5537It's configured to run at address 0x00040004, so you can play with it
5538like that:
5539
5540 => loads
5541 ## Ready for S-Record download ...
5542 ~>examples/hello_world.srec
5543 1 2 3 4 5 6 7 8 9 10 11 ...
5544 [file transfer complete]
5545 [connected]
5546 ## Start Addr = 0x00040004
5547
5548 => go 40004 Hello World! This is a test.
5549 ## Starting application at 0x00040004 ...
5550 Hello World
5551 argc = 7
5552 argv[0] = "40004"
5553 argv[1] = "Hello"
5554 argv[2] = "World!"
5555 argv[3] = "This"
5556 argv[4] = "is"
5557 argv[5] = "a"
5558 argv[6] = "test."
5559 argv[7] = "<NULL>"
5560 Hit any key to exit ...
5561
5562 ## Application terminated, rc = 0x0
5563
5564Another example, which demonstrates how to register a CPM interrupt
5565handler with the U-Boot code, can be found in 'examples/timer.c'.
5566Here, a CPM timer is set up to generate an interrupt every second.
5567The interrupt service routine is trivial, just printing a '.'
5568character, but this is just a demo program. The application can be
5569controlled by the following keys:
5570
5571 ? - print current values og the CPM Timer registers
5572 b - enable interrupts and start timer
5573 e - stop timer and disable interrupts
5574 q - quit application
5575
5576 => loads
5577 ## Ready for S-Record download ...
5578 ~>examples/timer.srec
5579 1 2 3 4 5 6 7 8 9 10 11 ...
5580 [file transfer complete]
5581 [connected]
5582 ## Start Addr = 0x00040004
5583
5584 => go 40004
5585 ## Starting application at 0x00040004 ...
5586 TIMERS=0xfff00980
5587 Using timer 1
5588 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5589
5590Hit 'b':
5591 [q, b, e, ?] Set interval 1000000 us
5592 Enabling timer
5593Hit '?':
5594 [q, b, e, ?] ........
5595 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5596Hit '?':
5597 [q, b, e, ?] .
5598 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5599Hit '?':
5600 [q, b, e, ?] .
5601 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5602Hit '?':
5603 [q, b, e, ?] .
5604 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5605Hit 'e':
5606 [q, b, e, ?] ...Stopping timer
5607Hit 'q':
5608 [q, b, e, ?] ## Application terminated, rc = 0x0
5609
5610
5611Minicom warning:
5612================
5613
5614Over time, many people have reported problems when trying to use the
5615"minicom" terminal emulation program for serial download. I (wd)
5616consider minicom to be broken, and recommend not to use it. Under
5617Unix, I recommend to use C-Kermit for general purpose use (and
5618especially for kermit binary protocol download ("loadb" command), and
e53515a2
KP
5619use "cu" for S-Record download ("loads" command). See
5620http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5621for help with kermit.
5622
2729af9d
WD
5623
5624Nevertheless, if you absolutely want to use it try adding this
5625configuration to your "File transfer protocols" section:
5626
5627 Name Program Name U/D FullScr IO-Red. Multi
5628 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5629 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5630
5631
5632NetBSD Notes:
5633=============
5634
5635Starting at version 0.9.2, U-Boot supports NetBSD both as host
5636(build U-Boot) and target system (boots NetBSD/mpc8xx).
5637
5638Building requires a cross environment; it is known to work on
5639NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5640need gmake since the Makefiles are not compatible with BSD make).
5641Note that the cross-powerpc package does not install include files;
5642attempting to build U-Boot will fail because <machine/ansi.h> is
5643missing. This file has to be installed and patched manually:
5644
5645 # cd /usr/pkg/cross/powerpc-netbsd/include
5646 # mkdir powerpc
5647 # ln -s powerpc machine
5648 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5649 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5650
5651Native builds *don't* work due to incompatibilities between native
5652and U-Boot include files.
5653
5654Booting assumes that (the first part of) the image booted is a
5655stage-2 loader which in turn loads and then invokes the kernel
5656proper. Loader sources will eventually appear in the NetBSD source
5657tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2a8af187 5658meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
2729af9d
WD
5659
5660
5661Implementation Internals:
5662=========================
5663
5664The following is not intended to be a complete description of every
5665implementation detail. However, it should help to understand the
5666inner workings of U-Boot and make it easier to port it to custom
5667hardware.
5668
5669
5670Initial Stack, Global Data:
5671---------------------------
5672
5673The implementation of U-Boot is complicated by the fact that U-Boot
5674starts running out of ROM (flash memory), usually without access to
5675system RAM (because the memory controller is not initialized yet).
5676This means that we don't have writable Data or BSS segments, and BSS
5677is not initialized as zero. To be able to get a C environment working
5678at all, we have to allocate at least a minimal stack. Implementation
5679options for this are defined and restricted by the CPU used: Some CPU
5680models provide on-chip memory (like the IMMR area on MPC8xx and
5681MPC826x processors), on others (parts of) the data cache can be
5682locked as (mis-) used as memory, etc.
5683
218ca724 5684 Chris Hallinan posted a good summary of these issues to the
0668236b 5685 U-Boot mailing list:
2729af9d
WD
5686
5687 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5688 From: "Chris Hallinan" <[email protected]>
5689 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5690 ...
5691
5692 Correct me if I'm wrong, folks, but the way I understand it
5693 is this: Using DCACHE as initial RAM for Stack, etc, does not
5694 require any physical RAM backing up the cache. The cleverness
5695 is that the cache is being used as a temporary supply of
5696 necessary storage before the SDRAM controller is setup. It's
11ccc33f 5697 beyond the scope of this list to explain the details, but you
2729af9d
WD
5698 can see how this works by studying the cache architecture and
5699 operation in the architecture and processor-specific manuals.
5700
5701 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5702 is another option for the system designer to use as an
11ccc33f 5703 initial stack/RAM area prior to SDRAM being available. Either
2729af9d
WD
5704 option should work for you. Using CS 4 should be fine if your
5705 board designers haven't used it for something that would
5706 cause you grief during the initial boot! It is frequently not
5707 used.
5708
6d0f6bcf 5709 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
2729af9d
WD
5710 with your processor/board/system design. The default value
5711 you will find in any recent u-boot distribution in
8a316c9b 5712 walnut.h should work for you. I'd set it to a value larger
2729af9d
WD
5713 than your SDRAM module. If you have a 64MB SDRAM module, set
5714 it above 400_0000. Just make sure your board has no resources
5715 that are supposed to respond to that address! That code in
5716 start.S has been around a while and should work as is when
5717 you get the config right.
5718
5719 -Chris Hallinan
5720 DS4.COM, Inc.
5721
5722It is essential to remember this, since it has some impact on the C
5723code for the initialization procedures:
5724
5725* Initialized global data (data segment) is read-only. Do not attempt
5726 to write it.
5727
11ccc33f 5728* Do not use any uninitialized global data (or implicitely initialized
2729af9d
WD
5729 as zero data - BSS segment) at all - this is undefined, initiali-
5730 zation is performed later (when relocating to RAM).
5731
5732* Stack space is very limited. Avoid big data buffers or things like
5733 that.
5734
5735Having only the stack as writable memory limits means we cannot use
5736normal global data to share information beween the code. But it
5737turned out that the implementation of U-Boot can be greatly
5738simplified by making a global data structure (gd_t) available to all
5739functions. We could pass a pointer to this data as argument to _all_
5740functions, but this would bloat the code. Instead we use a feature of
5741the GCC compiler (Global Register Variables) to share the data: we
5742place a pointer (gd) to the global data into a register which we
5743reserve for this purpose.
5744
5745When choosing a register for such a purpose we are restricted by the
5746relevant (E)ABI specifications for the current architecture, and by
5747GCC's implementation.
5748
5749For PowerPC, the following registers have specific use:
5750 R1: stack pointer
e7670f6c 5751 R2: reserved for system use
2729af9d
WD
5752 R3-R4: parameter passing and return values
5753 R5-R10: parameter passing
5754 R13: small data area pointer
5755 R30: GOT pointer
5756 R31: frame pointer
5757
e6bee808
JT
5758 (U-Boot also uses R12 as internal GOT pointer. r12
5759 is a volatile register so r12 needs to be reset when
5760 going back and forth between asm and C)
2729af9d 5761
e7670f6c 5762 ==> U-Boot will use R2 to hold a pointer to the global data
2729af9d
WD
5763
5764 Note: on PPC, we could use a static initializer (since the
5765 address of the global data structure is known at compile time),
5766 but it turned out that reserving a register results in somewhat
5767 smaller code - although the code savings are not that big (on
5768 average for all boards 752 bytes for the whole U-Boot image,
5769 624 text + 127 data).
5770
c4db335c 5771On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4c58eb55
MF
5772 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5773
c4db335c 5774 ==> U-Boot will use P3 to hold a pointer to the global data
4c58eb55 5775
2729af9d
WD
5776On ARM, the following registers are used:
5777
5778 R0: function argument word/integer result
5779 R1-R3: function argument word
12eba1b4
JH
5780 R9: platform specific
5781 R10: stack limit (used only if stack checking is enabled)
2729af9d
WD
5782 R11: argument (frame) pointer
5783 R12: temporary workspace
5784 R13: stack pointer
5785 R14: link register
5786 R15: program counter
5787
12eba1b4
JH
5788 ==> U-Boot will use R9 to hold a pointer to the global data
5789
5790 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
2729af9d 5791
0df01fd3
TC
5792On Nios II, the ABI is documented here:
5793 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5794
5795 ==> U-Boot will use gp to hold a pointer to the global data
5796
5797 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5798 to access small data sections, so gp is free.
5799
afc1ce82
ML
5800On NDS32, the following registers are used:
5801
5802 R0-R1: argument/return
5803 R2-R5: argument
5804 R15: temporary register for assembler
5805 R16: trampoline register
5806 R28: frame pointer (FP)
5807 R29: global pointer (GP)
5808 R30: link register (LP)
5809 R31: stack pointer (SP)
5810 PC: program counter (PC)
5811
5812 ==> U-Boot will use R10 to hold a pointer to the global data
5813
d87080b7
WD
5814NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5815or current versions of GCC may "optimize" the code too much.
2729af9d
WD
5816
5817Memory Management:
5818------------------
5819
5820U-Boot runs in system state and uses physical addresses, i.e. the
5821MMU is not used either for address mapping nor for memory protection.
5822
5823The available memory is mapped to fixed addresses using the memory
5824controller. In this process, a contiguous block is formed for each
5825memory type (Flash, SDRAM, SRAM), even when it consists of several
5826physical memory banks.
5827
5828U-Boot is installed in the first 128 kB of the first Flash bank (on
5829TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5830booting and sizing and initializing DRAM, the code relocates itself
5831to the upper end of DRAM. Immediately below the U-Boot code some
6d0f6bcf 5832memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
2729af9d
WD
5833configuration setting]. Below that, a structure with global Board
5834Info data is placed, followed by the stack (growing downward).
5835
5836Additionally, some exception handler code is copied to the low 8 kB
5837of DRAM (0x00000000 ... 0x00001FFF).
5838
5839So a typical memory configuration with 16 MB of DRAM could look like
5840this:
5841
5842 0x0000 0000 Exception Vector code
5843 :
5844 0x0000 1FFF
5845 0x0000 2000 Free for Application Use
5846 :
5847 :
5848
5849 :
5850 :
5851 0x00FB FF20 Monitor Stack (Growing downward)
5852 0x00FB FFAC Board Info Data and permanent copy of global data
5853 0x00FC 0000 Malloc Arena
5854 :
5855 0x00FD FFFF
5856 0x00FE 0000 RAM Copy of Monitor Code
5857 ... eventually: LCD or video framebuffer
5858 ... eventually: pRAM (Protected RAM - unchanged by reset)
5859 0x00FF FFFF [End of RAM]
5860
5861
5862System Initialization:
5863----------------------
c609719b 5864
2729af9d 5865In the reset configuration, U-Boot starts at the reset entry point
11ccc33f 5866(on most PowerPC systems at address 0x00000100). Because of the reset
2729af9d
WD
5867configuration for CS0# this is a mirror of the onboard Flash memory.
5868To be able to re-map memory U-Boot then jumps to its link address.
5869To be able to implement the initialization code in C, a (small!)
5870initial stack is set up in the internal Dual Ported RAM (in case CPUs
5871which provide such a feature like MPC8xx or MPC8260), or in a locked
5872part of the data cache. After that, U-Boot initializes the CPU core,
5873the caches and the SIU.
5874
5875Next, all (potentially) available memory banks are mapped using a
5876preliminary mapping. For example, we put them on 512 MB boundaries
5877(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5878on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5879programmed for SDRAM access. Using the temporary configuration, a
5880simple memory test is run that determines the size of the SDRAM
5881banks.
5882
5883When there is more than one SDRAM bank, and the banks are of
5884different size, the largest is mapped first. For equal size, the first
5885bank (CS2#) is mapped first. The first mapping is always for address
58860x00000000, with any additional banks following immediately to create
5887contiguous memory starting from 0.
5888
5889Then, the monitor installs itself at the upper end of the SDRAM area
5890and allocates memory for use by malloc() and for the global Board
5891Info data; also, the exception vector code is copied to the low RAM
5892pages, and the final stack is set up.
5893
5894Only after this relocation will you have a "normal" C environment;
5895until that you are restricted in several ways, mostly because you are
5896running from ROM, and because the code will have to be relocated to a
5897new address in RAM.
5898
5899
5900U-Boot Porting Guide:
5901----------------------
c609719b 5902
2729af9d
WD
5903[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5904list, October 2002]
c609719b
WD
5905
5906
6c3fef28 5907int main(int argc, char *argv[])
2729af9d
WD
5908{
5909 sighandler_t no_more_time;
c609719b 5910
6c3fef28
JVB
5911 signal(SIGALRM, no_more_time);
5912 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
c609719b 5913
2729af9d 5914 if (available_money > available_manpower) {
6c3fef28 5915 Pay consultant to port U-Boot;
c609719b
WD
5916 return 0;
5917 }
5918
2729af9d
WD
5919 Download latest U-Boot source;
5920
0668236b 5921 Subscribe to u-boot mailing list;
2729af9d 5922
6c3fef28
JVB
5923 if (clueless)
5924 email("Hi, I am new to U-Boot, how do I get started?");
2729af9d
WD
5925
5926 while (learning) {
5927 Read the README file in the top level directory;
6c3fef28
JVB
5928 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5929 Read applicable doc/*.README;
2729af9d 5930 Read the source, Luke;
6c3fef28 5931 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
2729af9d
WD
5932 }
5933
6c3fef28
JVB
5934 if (available_money > toLocalCurrency ($2500))
5935 Buy a BDI3000;
5936 else
2729af9d 5937 Add a lot of aggravation and time;
2729af9d 5938
6c3fef28
JVB
5939 if (a similar board exists) { /* hopefully... */
5940 cp -a board/<similar> board/<myboard>
5941 cp include/configs/<similar>.h include/configs/<myboard>.h
5942 } else {
5943 Create your own board support subdirectory;
5944 Create your own board include/configs/<myboard>.h file;
5945 }
5946 Edit new board/<myboard> files
5947 Edit new include/configs/<myboard>.h
5948
5949 while (!accepted) {
5950 while (!running) {
5951 do {
5952 Add / modify source code;
5953 } until (compiles);
5954 Debug;
5955 if (clueless)
5956 email("Hi, I am having problems...");
5957 }
5958 Send patch file to the U-Boot email list;
5959 if (reasonable critiques)
5960 Incorporate improvements from email list code review;
5961 else
5962 Defend code as written;
2729af9d 5963 }
2729af9d
WD
5964
5965 return 0;
5966}
5967
5968void no_more_time (int sig)
5969{
5970 hire_a_guru();
5971}
5972
c609719b 5973
2729af9d
WD
5974Coding Standards:
5975-----------------
c609719b 5976
2729af9d 5977All contributions to U-Boot should conform to the Linux kernel
2c051651 5978coding style; see the file "Documentation/CodingStyle" and the script
7ca9296e 5979"scripts/Lindent" in your Linux kernel source directory.
2c051651
DZ
5980
5981Source files originating from a different project (for example the
5982MTD subsystem) are generally exempt from these guidelines and are not
5983reformated to ease subsequent migration to newer versions of those
5984sources.
5985
5986Please note that U-Boot is implemented in C (and to some small parts in
5987Assembler); no C++ is used, so please do not use C++ style comments (//)
5988in your code.
c609719b 5989
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5990Please also stick to the following formatting rules:
5991- remove any trailing white space
7ca9296e 5992- use TAB characters for indentation and vertical alignment, not spaces
2729af9d 5993- make sure NOT to use DOS '\r\n' line feeds
7ca9296e 5994- do not add more than 2 consecutive empty lines to source files
2729af9d 5995- do not add trailing empty lines to source files
180d3f74 5996
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5997Submissions which do not conform to the standards may be returned
5998with a request to reformat the changes.
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5999
6000
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6001Submitting Patches:
6002-------------------
c609719b 6003
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6004Since the number of patches for U-Boot is growing, we need to
6005establish some rules. Submissions which do not conform to these rules
6006may be rejected, even when they contain important and valuable stuff.
c609719b 6007
0d28f34b 6008Please see http://www.denx.de/wiki/U-Boot/Patches for details.
218ca724 6009
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6010Patches shall be sent to the u-boot mailing list <[email protected]>;
6011see http://lists.denx.de/mailman/listinfo/u-boot
6012
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6013When you send a patch, please include the following information with
6014it:
c609719b 6015
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6016* For bug fixes: a description of the bug and how your patch fixes
6017 this bug. Please try to include a way of demonstrating that the
6018 patch actually fixes something.
c609719b 6019
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6020* For new features: a description of the feature and your
6021 implementation.
c609719b 6022
2729af9d 6023* A CHANGELOG entry as plaintext (separate from the patch)
c609719b 6024
2729af9d 6025* For major contributions, your entry to the CREDITS file
c609719b 6026
27af930e
AA
6027* When you add support for a new board, don't forget to add a
6028 maintainer e-mail address to the boards.cfg file, too.
c609719b 6029
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6030* If your patch adds new configuration options, don't forget to
6031 document these in the README file.
c609719b 6032
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6033* The patch itself. If you are using git (which is *strongly*
6034 recommended) you can easily generate the patch using the
7ca9296e 6035 "git format-patch". If you then use "git send-email" to send it to
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6036 the U-Boot mailing list, you will avoid most of the common problems
6037 with some other mail clients.
6038
6039 If you cannot use git, use "diff -purN OLD NEW". If your version of
6040 diff does not support these options, then get the latest version of
6041 GNU diff.
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6043 The current directory when running this command shall be the parent
6044 directory of the U-Boot source tree (i. e. please make sure that
6045 your patch includes sufficient directory information for the
6046 affected files).
6dff5529 6047
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6048 We prefer patches as plain text. MIME attachments are discouraged,
6049 and compressed attachments must not be used.
c609719b 6050
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6051* If one logical set of modifications affects or creates several
6052 files, all these changes shall be submitted in a SINGLE patch file.
52f52c14 6053
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6054* Changesets that contain different, unrelated modifications shall be
6055 submitted as SEPARATE patches, one patch per changeset.
8bde7f77 6056
52f52c14 6057
2729af9d 6058Notes:
c609719b 6059
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6060* Before sending the patch, run the MAKEALL script on your patched
6061 source tree and make sure that no errors or warnings are reported
6062 for any of the boards.
c609719b 6063
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6064* Keep your modifications to the necessary minimum: A patch
6065 containing several unrelated changes or arbitrary reformats will be
6066 returned with a request to re-formatting / split it.
c609719b 6067
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6068* If you modify existing code, make sure that your new code does not
6069 add to the memory footprint of the code ;-) Small is beautiful!
6070 When adding new features, these should compile conditionally only
6071 (using #ifdef), and the resulting code with the new feature
6072 disabled must not need more memory than the old code without your
6073 modification.
90dc6704 6074
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6075* Remember that there is a size limit of 100 kB per message on the
6076 u-boot mailing list. Bigger patches will be moderated. If they are
6077 reasonable and not too big, they will be acknowledged. But patches
6078 bigger than the size limit should be avoided.
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