2 # (C) Copyright 2000 - 2013
5 # SPDX-License-Identifier: GPL-2.0+
11 This directory contains the source code for U-Boot, a boot loader for
12 Embedded boards based on PowerPC, ARM, MIPS and several other
13 processors, which can be installed in a boot ROM and used to
14 initialize and test the hardware or to download and run application
17 The development of U-Boot is closely related to Linux: some parts of
18 the source code originate in the Linux source tree, we have some
19 header files in common, and special provision has been made to
20 support booting of Linux images.
22 Some attention has been paid to make this software easily
23 configurable and extendable. For instance, all monitor commands are
24 implemented with the same call interface, so that it's very easy to
25 add new commands. Also, instead of permanently adding rarely used
26 code (for instance hardware test utilities) to the monitor, you can
27 load and run it dynamically.
33 In general, all boards for which a configuration option exists in the
34 Makefile have been tested to some extent and can be considered
35 "working". In fact, many of them are used in production systems.
37 In case of problems see the CHANGELOG and CREDITS files to find out
38 who contributed the specific port. The boards.cfg file lists board
41 Note: There is no CHANGELOG file in the actual U-Boot source tree;
42 it can be created dynamically from the Git log using:
50 In case you have questions about, problems with or contributions for
51 U-Boot you should send a message to the U-Boot mailing list at
53 on the mailing list - please search the archive before asking FAQ's.
54 Please see http://lists.denx.de/pipermail/u-boot and
55 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
58 Where to get source code:
59 =========================
61 The U-Boot source code is maintained in the git repository at
62 git://www.denx.de/git/u-boot.git ; you can browse it online at
63 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
65 The "snapshot" links on this page allow you to download tarballs of
66 any version you might be interested in. Official releases are also
67 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70 Pre-built (and tested) images are available from
71 ftp://ftp.denx.de/pub/u-boot/images/
77 - start from 8xxrom sources
78 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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
86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
87 - create ARMBoot project (http://sourceforge.net/projects/armboot)
88 - add other CPU families (starting with ARM)
89 - create U-Boot project (http://sourceforge.net/projects/u-boot)
90 - current project page: see http://www.denx.de/wiki/U-Boot
96 The "official" name of this project is "Das U-Boot". The spelling
97 "U-Boot" shall be used in all written text (documentation, comments
98 in source files etc.). Example:
100 This is the README file for the U-Boot project.
102 File names etc. shall be based on the string "u-boot". Examples:
104 include/asm-ppc/u-boot.h
106 #include <asm/u-boot.h>
108 Variable names, preprocessor constants etc. shall be either based on
109 the string "u_boot" or on "U_BOOT". Example:
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
118 Starting with the release in October 2008, the names of the releases
119 were changed from numerical release numbers without deeper meaning
120 into a time stamp based numbering. Regular releases are identified by
121 names consisting of the calendar year and month of the release date.
122 Additional fields (if present) indicate release candidates or bug fix
123 releases in "stable" maintenance trees.
126 U-Boot v2009.11 - Release November 2009
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
134 /arch Architecture specific files
135 /arc Files generic to ARC architecture
136 /cpu CPU specific files
137 /arc700 Files specific to ARC 700 CPUs
138 /lib Architecture specific library files
139 /arm Files generic to ARM architecture
140 /cpu CPU specific files
141 /arm720t Files specific to ARM 720 CPUs
142 /arm920t Files specific to ARM 920 CPUs
143 /at91 Files specific to Atmel AT91RM9200 CPU
144 /imx Files specific to Freescale MC9328 i.MX CPUs
145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
146 /arm926ejs Files specific to ARM 926 CPUs
147 /arm1136 Files specific to ARM 1136 CPUs
148 /pxa Files specific to Intel XScale PXA CPUs
149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
150 /lib Architecture specific library files
151 /avr32 Files generic to AVR32 architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /blackfin Files generic to Analog Devices Blackfin architecture
155 /cpu CPU specific files
156 /lib Architecture specific library files
157 /m68k Files generic to m68k architecture
158 /cpu CPU specific files
159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 /lib Architecture specific library files
165 /microblaze Files generic to microblaze architecture
166 /cpu CPU specific files
167 /lib Architecture specific library files
168 /mips Files generic to MIPS architecture
169 /cpu CPU specific files
170 /mips32 Files specific to MIPS32 CPUs
171 /mips64 Files specific to MIPS64 CPUs
172 /lib Architecture specific library files
173 /nds32 Files generic to NDS32 architecture
174 /cpu CPU specific files
175 /n1213 Files specific to Andes Technology N1213 CPUs
176 /lib Architecture specific library files
177 /nios2 Files generic to Altera NIOS2 architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /openrisc Files generic to OpenRISC architecture
181 /cpu CPU specific files
182 /lib Architecture specific library files
183 /powerpc Files generic to PowerPC architecture
184 /cpu CPU specific files
185 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
186 /mpc5xx Files specific to Freescale MPC5xx CPUs
187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
188 /mpc8xx Files specific to Freescale MPC8xx CPUs
189 /mpc824x Files specific to Freescale MPC824x CPUs
190 /mpc8260 Files specific to Freescale MPC8260 CPUs
191 /mpc85xx Files specific to Freescale MPC85xx CPUs
192 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
193 /lib Architecture specific library files
194 /sh Files generic to SH architecture
195 /cpu CPU specific files
196 /sh2 Files specific to sh2 CPUs
197 /sh3 Files specific to sh3 CPUs
198 /sh4 Files specific to sh4 CPUs
199 /lib Architecture specific library files
200 /sparc Files generic to SPARC architecture
201 /cpu CPU specific files
202 /leon2 Files specific to Gaisler LEON2 SPARC CPU
203 /leon3 Files specific to Gaisler LEON3 SPARC CPU
204 /lib Architecture specific library files
205 /x86 Files generic to x86 architecture
206 /cpu CPU specific files
207 /lib Architecture specific library files
208 /api Machine/arch independent API for external apps
209 /board Board dependent files
210 /common Misc architecture independent functions
211 /disk Code for disk drive partition handling
212 /doc Documentation (don't expect too much)
213 /drivers Commonly used device drivers
214 /dts Contains Makefile for building internal U-Boot fdt.
215 /examples Example code for standalone applications, etc.
216 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
217 /include Header Files
218 /lib Files generic to all architectures
219 /libfdt Library files to support flattened device trees
220 /lzma Library files to support LZMA decompression
221 /lzo Library files to support LZO decompression
223 /post Power On Self Test
224 /spl Secondary Program Loader framework
225 /tools Tools to build S-Record or U-Boot images, etc.
227 Software Configuration:
228 =======================
230 Configuration is usually done using C preprocessor defines; the
231 rationale behind that is to avoid dead code whenever possible.
233 There are two classes of configuration variables:
235 * Configuration _OPTIONS_:
236 These are selectable by the user and have names beginning with
239 * Configuration _SETTINGS_:
240 These depend on the hardware etc. and should not be meddled with if
241 you don't know what you're doing; they have names beginning with
244 Later we will add a configuration tool - probably similar to or even
245 identical to what's used for the Linux kernel. Right now, we have to
246 do the configuration by hand, which means creating some symbolic
247 links and editing some configuration files. We use the TQM8xxL boards
251 Selection of Processor Architecture and Board Type:
252 ---------------------------------------------------
254 For all supported boards there are ready-to-use default
255 configurations available; just type "make <board_name>_defconfig".
257 Example: For a TQM823L module type:
260 make TQM823L_defconfig
262 For the Cogent platform, you need to specify the CPU type as well;
263 e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent
264 directory according to the instructions in cogent/README.
270 U-Boot can be built natively to run on a Linux host using the 'sandbox'
271 board. This allows feature development which is not board- or architecture-
272 specific to be undertaken on a native platform. The sandbox is also used to
273 run some of U-Boot's tests.
275 See board/sandbox/sandbox/README.sandbox for more details.
278 Configuration Options:
279 ----------------------
281 Configuration depends on the combination of board and CPU type; all
282 such information is kept in a configuration file
283 "include/configs/<board_name>.h".
285 Example: For a TQM823L module, all configuration settings are in
286 "include/configs/TQM823L.h".
289 Many of the options are named exactly as the corresponding Linux
290 kernel configuration options. The intention is to make it easier to
291 build a config tool - later.
294 The following options need to be configured:
296 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
298 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
300 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
301 Define exactly one, e.g. CONFIG_ATSTK1002
303 - CPU Module Type: (if CONFIG_COGENT is defined)
304 Define exactly one of
306 --- FIXME --- not tested yet:
307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
308 CONFIG_CMA287_23, CONFIG_CMA287_50
310 - Motherboard Type: (if CONFIG_COGENT is defined)
311 Define exactly one of
312 CONFIG_CMA101, CONFIG_CMA102
314 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
315 Define one or more of
318 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
319 Define one or more of
320 CONFIG_LCD_HEARTBEAT - update a character position on
321 the LCD display every second with
324 - Marvell Family Member
325 CONFIG_SYS_MVFS - define it if you want to enable
326 multiple fs option at one time
327 for marvell soc family
329 - MPC824X Family Member (if CONFIG_MPC824X is defined)
330 Define exactly one of
331 CONFIG_MPC8240, CONFIG_MPC8245
333 - 8xx CPU Options: (if using an MPC8xx CPU)
334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
335 get_gclk_freq() cannot work
336 e.g. if there is no 32KHz
337 reference PIT/RTC clock
338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
341 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
342 CONFIG_SYS_8xx_CPUCLK_MIN
343 CONFIG_SYS_8xx_CPUCLK_MAX
344 CONFIG_8xx_CPUCLK_DEFAULT
345 See doc/README.MPC866
347 CONFIG_SYS_MEASURE_CPUCLK
349 Define this to measure the actual CPU clock instead
350 of relying on the correctness of the configured
351 values. Mostly useful for board bringup to make sure
352 the PLL is locked at the intended frequency. Note
353 that this requires a (stable) reference clock (32 kHz
354 RTC clock or CONFIG_SYS_8XX_XIN)
356 CONFIG_SYS_DELAYED_ICACHE
358 Define this option if you want to enable the
359 ICache only when Code runs from RAM.
364 Specifies that the core is a 64-bit PowerPC implementation (implements
365 the "64" category of the Power ISA). This is necessary for ePAPR
366 compliance, among other possible reasons.
368 CONFIG_SYS_FSL_TBCLK_DIV
370 Defines the core time base clock divider ratio compared to the
371 system clock. On most PQ3 devices this is 8, on newer QorIQ
372 devices it can be 16 or 32. The ratio varies from SoC to Soc.
374 CONFIG_SYS_FSL_PCIE_COMPAT
376 Defines the string to utilize when trying to match PCIe device
377 tree nodes for the given platform.
379 CONFIG_SYS_PPC_E500_DEBUG_TLB
381 Enables a temporary TLB entry to be used during boot to work
382 around limitations in e500v1 and e500v2 external debugger
383 support. This reduces the portions of the boot code where
384 breakpoints and single stepping do not work. The value of this
385 symbol should be set to the TLB1 entry to be used for this
388 CONFIG_SYS_FSL_ERRATUM_A004510
390 Enables a workaround for erratum A004510. If set,
391 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
392 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
394 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
395 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
397 Defines one or two SoC revisions (low 8 bits of SVR)
398 for which the A004510 workaround should be applied.
400 The rest of SVR is either not relevant to the decision
401 of whether the erratum is present (e.g. p2040 versus
402 p2041) or is implied by the build target, which controls
403 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
405 See Freescale App Note 4493 for more information about
408 CONFIG_A003399_NOR_WORKAROUND
409 Enables a workaround for IFC erratum A003399. It is only
410 requred during NOR boot.
412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
414 This is the value to write into CCSR offset 0x18600
415 according to the A004510 workaround.
417 CONFIG_SYS_FSL_DSP_DDR_ADDR
418 This value denotes start offset of DDR memory which is
419 connected exclusively to the DSP cores.
421 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
422 This value denotes start offset of M2 memory
423 which is directly connected to the DSP core.
425 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
426 This value denotes start offset of M3 memory which is directly
427 connected to the DSP core.
429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
430 This value denotes start offset of DSP CCSR space.
432 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
433 Single Source Clock is clocking mode present in some of FSL SoC's.
434 In this mode, a single differential clock is used to supply
435 clocks to the sysclock, ddrclock and usbclock.
437 CONFIG_SYS_CPC_REINIT_F
438 This CONFIG is defined when the CPC is configured as SRAM at the
439 time of U-boot entry and is required to be re-initialized.
442 Inidcates this SoC supports deep sleep feature. If deep sleep is
443 supported, core will start to execute uboot when wakes up.
445 - Generic CPU options:
446 CONFIG_SYS_GENERIC_GLOBAL_DATA
447 Defines global data is initialized in generic board board_init_f().
448 If this macro is defined, global data is created and cleared in
449 generic board board_init_f(). Without this macro, architecture/board
450 should initialize global data before calling board_init_f().
452 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
454 Defines the endianess of the CPU. Implementation of those
455 values is arch specific.
458 Freescale DDR driver in use. This type of DDR controller is
459 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
462 CONFIG_SYS_FSL_DDR_ADDR
463 Freescale DDR memory-mapped register base.
465 CONFIG_SYS_FSL_DDR_EMU
466 Specify emulator support for DDR. Some DDR features such as
467 deskew training are not available.
469 CONFIG_SYS_FSL_DDRC_GEN1
470 Freescale DDR1 controller.
472 CONFIG_SYS_FSL_DDRC_GEN2
473 Freescale DDR2 controller.
475 CONFIG_SYS_FSL_DDRC_GEN3
476 Freescale DDR3 controller.
478 CONFIG_SYS_FSL_DDRC_GEN4
479 Freescale DDR4 controller.
481 CONFIG_SYS_FSL_DDRC_ARM_GEN3
482 Freescale DDR3 controller for ARM-based SoCs.
485 Board config to use DDR1. It can be enabled for SoCs with
486 Freescale DDR1 or DDR2 controllers, depending on the board
490 Board config to use DDR2. It can be eanbeld for SoCs with
491 Freescale DDR2 or DDR3 controllers, depending on the board
495 Board config to use DDR3. It can be enabled for SoCs with
496 Freescale DDR3 or DDR3L controllers.
499 Board config to use DDR3L. It can be enabled for SoCs with
503 Board config to use DDR4. It can be enabled for SoCs with
506 CONFIG_SYS_FSL_IFC_BE
507 Defines the IFC controller register space as Big Endian
509 CONFIG_SYS_FSL_IFC_LE
510 Defines the IFC controller register space as Little Endian
512 CONFIG_SYS_FSL_PBL_PBI
513 It enables addition of RCW (Power on reset configuration) in built image.
514 Please refer doc/README.pblimage for more details
516 CONFIG_SYS_FSL_PBL_RCW
517 It adds PBI(pre-boot instructions) commands in u-boot build image.
518 PBI commands can be used to configure SoC before it starts the execution.
519 Please refer doc/README.pblimage for more details
522 It adds a target to create boot binary having SPL binary in PBI format
523 concatenated with u-boot binary.
525 CONFIG_SYS_FSL_DDR_BE
526 Defines the DDR controller register space as Big Endian
528 CONFIG_SYS_FSL_DDR_LE
529 Defines the DDR controller register space as Little Endian
531 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
532 Physical address from the view of DDR controllers. It is the
533 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
534 it could be different for ARM SoCs.
536 CONFIG_SYS_FSL_DDR_INTLV_256B
537 DDR controller interleaving on 256-byte. This is a special
538 interleaving mode, handled by Dickens for Freescale layerscape
541 - Intel Monahans options:
542 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
544 Defines the Monahans run mode to oscillator
545 ratio. Valid values are 8, 16, 24, 31. The core
546 frequency is this value multiplied by 13 MHz.
548 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
550 Defines the Monahans turbo mode to oscillator
551 ratio. Valid values are 1 (default if undefined) and
552 2. The core frequency as calculated above is multiplied
556 CONFIG_SYS_INIT_SP_OFFSET
558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
559 pointer. This is needed for the temporary stack before
562 CONFIG_SYS_MIPS_CACHE_MODE
564 Cache operation mode for the MIPS CPU.
565 See also arch/mips/include/asm/mipsregs.h.
567 CONF_CM_CACHABLE_NO_WA
570 CONF_CM_CACHABLE_NONCOHERENT
574 CONF_CM_CACHABLE_ACCELERATED
576 CONFIG_SYS_XWAY_EBU_BOOTCFG
578 Special option for Lantiq XWAY SoCs for booting from NOR flash.
579 See also arch/mips/cpu/mips32/start.S.
581 CONFIG_XWAY_SWAP_BYTES
583 Enable compilation of tools/xway-swap-bytes needed for Lantiq
584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
585 be swapped if a flash programmer is used.
588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
590 Select high exception vectors of the ARM core, e.g., do not
591 clear the V bit of the c1 register of CP15.
593 CONFIG_SYS_THUMB_BUILD
595 Use this flag to build U-Boot using the Thumb instruction
596 set for ARM architectures. Thumb instruction set provides
597 better code density. For ARM architectures that support
598 Thumb2 this flag will result in Thumb2 code generated by
601 CONFIG_ARM_ERRATA_716044
602 CONFIG_ARM_ERRATA_742230
603 CONFIG_ARM_ERRATA_743622
604 CONFIG_ARM_ERRATA_751472
605 CONFIG_ARM_ERRATA_794072
606 CONFIG_ARM_ERRATA_761320
608 If set, the workarounds for these ARM errata are applied early
609 during U-Boot startup. Note that these options force the
610 workarounds to be applied; no CPU-type/version detection
611 exists, unlike the similar options in the Linux kernel. Do not
612 set these options unless they apply!
617 The frequency of the timer returned by get_timer().
618 get_timer() must operate in milliseconds and this CONFIG
619 option must be set to 1000.
621 - Linux Kernel Interface:
624 U-Boot stores all clock information in Hz
625 internally. For binary compatibility with older Linux
626 kernels (which expect the clocks passed in the
627 bd_info data to be in MHz) the environment variable
628 "clocks_in_mhz" can be defined so that U-Boot
629 converts clock data to MHZ before passing it to the
631 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
632 "clocks_in_mhz=1" is automatically included in the
635 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
637 When transferring memsize parameter to linux, some versions
638 expect it to be in bytes, others in MB.
639 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
643 New kernel versions are expecting firmware settings to be
644 passed using flattened device trees (based on open firmware
648 * New libfdt-based support
649 * Adds the "fdt" command
650 * The bootm command automatically updates the fdt
652 OF_CPU - The proper name of the cpus node (only required for
653 MPC512X and MPC5xxx based boards).
654 OF_SOC - The proper name of the soc node (only required for
655 MPC512X and MPC5xxx based boards).
656 OF_TBCLK - The timebase frequency.
657 OF_STDOUT_PATH - The path to the console device
659 boards with QUICC Engines require OF_QE to set UCC MAC
662 CONFIG_OF_BOARD_SETUP
664 Board code has addition modification that it wants to make
665 to the flat device tree before handing it off to the kernel
669 This define fills in the correct boot CPU in the boot
670 param header, the default value is zero if undefined.
674 U-Boot can detect if an IDE device is present or not.
675 If not, and this new config option is activated, U-Boot
676 removes the ATA node from the DTS before booting Linux,
677 so the Linux IDE driver does not probe the device and
678 crash. This is needed for buggy hardware (uc101) where
679 no pull down resistor is connected to the signal IDE5V_DD7.
681 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
683 This setting is mandatory for all boards that have only one
684 machine type and must be used to specify the machine type
685 number as it appears in the ARM machine registry
686 (see http://www.arm.linux.org.uk/developer/machines/).
687 Only boards that have multiple machine types supported
688 in a single configuration file and the machine type is
689 runtime discoverable, do not have to use this setting.
691 - vxWorks boot parameters:
693 bootvx constructs a valid bootline using the following
694 environments variables: bootfile, ipaddr, serverip, hostname.
695 It loads the vxWorks image pointed bootfile.
697 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
698 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
699 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
700 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
702 CONFIG_SYS_VXWORKS_ADD_PARAMS
704 Add it at the end of the bootline. E.g "u=username pw=secret"
706 Note: If a "bootargs" environment is defined, it will overwride
707 the defaults discussed just above.
709 - Cache Configuration:
710 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
711 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
712 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
714 - Cache Configuration for ARM:
715 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
717 CONFIG_SYS_PL310_BASE - Physical base address of PL310
718 controller register space
723 Define this if you want support for Amba PrimeCell PL010 UARTs.
727 Define this if you want support for Amba PrimeCell PL011 UARTs.
731 If you have Amba PrimeCell PL011 UARTs, set this variable to
732 the clock speed of the UARTs.
736 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
737 define this to a list of base addresses for each (supported)
738 port. See e.g. include/configs/versatile.h
740 CONFIG_PL011_SERIAL_RLCR
742 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
743 have separate receive and transmit line control registers. Set
744 this variable to initialize the extra register.
746 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
748 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
749 boot loader that has already initialized the UART. Define this
750 variable to flush the UART at init time.
752 CONFIG_SERIAL_HW_FLOW_CONTROL
754 Define this variable to enable hw flow control in serial driver.
755 Current user of this option is drivers/serial/nsl16550.c driver
758 Depending on board, define exactly one serial port
759 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
760 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
761 console by defining CONFIG_8xx_CONS_NONE
763 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
764 port routines must be defined elsewhere
765 (i.e. serial_init(), serial_getc(), ...)
768 Enables console device for a color framebuffer. Needs following
769 defines (cf. smiLynxEM, i8042)
770 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
772 VIDEO_HW_RECTFILL graphic chip supports
775 VIDEO_HW_BITBLT graphic chip supports
776 bit-blit (cf. smiLynxEM)
777 VIDEO_VISIBLE_COLS visible pixel columns
779 VIDEO_VISIBLE_ROWS visible pixel rows
780 VIDEO_PIXEL_SIZE bytes per pixel
781 VIDEO_DATA_FORMAT graphic data format
782 (0-5, cf. cfb_console.c)
783 VIDEO_FB_ADRS framebuffer address
784 VIDEO_KBD_INIT_FCT keyboard int fct
785 (i.e. i8042_kbd_init())
786 VIDEO_TSTC_FCT test char fct
788 VIDEO_GETC_FCT get char fct
790 CONFIG_CONSOLE_CURSOR cursor drawing on/off
791 (requires blink timer
793 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
794 CONFIG_CONSOLE_TIME display time/date info in
796 (requires CONFIG_CMD_DATE)
797 CONFIG_VIDEO_LOGO display Linux logo in
799 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
800 linux_logo.h for logo.
801 Requires CONFIG_VIDEO_LOGO
802 CONFIG_CONSOLE_EXTRA_INFO
803 additional board info beside
806 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
807 a limited number of ANSI escape sequences (cursor control,
808 erase functions and limited graphics rendition control).
810 When CONFIG_CFB_CONSOLE is defined, video console is
811 default i/o. Serial console can be forced with
812 environment 'console=serial'.
814 When CONFIG_SILENT_CONSOLE is defined, all console
815 messages (by U-Boot and Linux!) can be silenced with
816 the "silent" environment variable. See
817 doc/README.silent for more information.
819 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
821 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
825 CONFIG_BAUDRATE - in bps
826 Select one of the baudrates listed in
827 CONFIG_SYS_BAUDRATE_TABLE, see below.
828 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
830 - Console Rx buffer length
831 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
832 the maximum receive buffer length for the SMC.
833 This option is actual only for 82xx and 8xx possible.
834 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
835 must be defined, to setup the maximum idle timeout for
838 - Pre-Console Buffer:
839 Prior to the console being initialised (i.e. serial UART
840 initialised etc) all console output is silently discarded.
841 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
842 buffer any console messages prior to the console being
843 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
844 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
845 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
846 bytes are output before the console is initialised, the
847 earlier bytes are discarded.
849 'Sane' compilers will generate smaller code if
850 CONFIG_PRE_CON_BUF_SZ is a power of 2
852 - Safe printf() functions
853 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
854 the printf() functions. These are defined in
855 include/vsprintf.h and include snprintf(), vsnprintf() and
856 so on. Code size increase is approximately 300-500 bytes.
857 If this option is not given then these functions will
858 silently discard their buffer size argument - this means
859 you are not getting any overflow checking in this case.
861 - Boot Delay: CONFIG_BOOTDELAY - in seconds
862 Delay before automatically booting the default image;
863 set to -1 to disable autoboot.
864 set to -2 to autoboot with no delay and not check for abort
865 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
867 See doc/README.autoboot for these options that
868 work with CONFIG_BOOTDELAY. None are required.
869 CONFIG_BOOT_RETRY_TIME
870 CONFIG_BOOT_RETRY_MIN
871 CONFIG_AUTOBOOT_KEYED
872 CONFIG_AUTOBOOT_PROMPT
873 CONFIG_AUTOBOOT_DELAY_STR
874 CONFIG_AUTOBOOT_STOP_STR
875 CONFIG_AUTOBOOT_DELAY_STR2
876 CONFIG_AUTOBOOT_STOP_STR2
877 CONFIG_ZERO_BOOTDELAY_CHECK
878 CONFIG_RESET_TO_RETRY
882 Only needed when CONFIG_BOOTDELAY is enabled;
883 define a command string that is automatically executed
884 when no character is read on the console interface
885 within "Boot Delay" after reset.
888 This can be used to pass arguments to the bootm
889 command. The value of CONFIG_BOOTARGS goes into the
890 environment value "bootargs".
892 CONFIG_RAMBOOT and CONFIG_NFSBOOT
893 The value of these goes into the environment as
894 "ramboot" and "nfsboot" respectively, and can be used
895 as a convenience, when switching between booting from
899 CONFIG_BOOTCOUNT_LIMIT
900 Implements a mechanism for detecting a repeating reboot
902 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
905 If no softreset save registers are found on the hardware
906 "bootcount" is stored in the environment. To prevent a
907 saveenv on all reboots, the environment variable
908 "upgrade_available" is used. If "upgrade_available" is
909 0, "bootcount" is always 0, if "upgrade_available" is
910 1 "bootcount" is incremented in the environment.
911 So the Userspace Applikation must set the "upgrade_available"
912 and "bootcount" variable to 0, if a boot was successfully.
917 When this option is #defined, the existence of the
918 environment variable "preboot" will be checked
919 immediately before starting the CONFIG_BOOTDELAY
920 countdown and/or running the auto-boot command resp.
921 entering interactive mode.
923 This feature is especially useful when "preboot" is
924 automatically generated or modified. For an example
925 see the LWMON board specific code: here "preboot" is
926 modified when the user holds down a certain
927 combination of keys on the (special) keyboard when
930 - Serial Download Echo Mode:
932 If defined to 1, all characters received during a
933 serial download (using the "loads" command) are
934 echoed back. This might be needed by some terminal
935 emulations (like "cu"), but may as well just take
936 time on others. This setting #define's the initial
937 value of the "loads_echo" environment variable.
939 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
941 Select one of the baudrates listed in
942 CONFIG_SYS_BAUDRATE_TABLE, see below.
945 Monitor commands can be included or excluded
946 from the build by using the #include files
947 <config_cmd_all.h> and #undef'ing unwanted
948 commands, or using <config_cmd_default.h>
949 and augmenting with additional #define's
952 The default command configuration includes all commands
953 except those marked below with a "*".
955 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
956 CONFIG_CMD_ASKENV * ask for env variable
957 CONFIG_CMD_BDI bdinfo
958 CONFIG_CMD_BEDBUG * Include BedBug Debugger
959 CONFIG_CMD_BMP * BMP support
960 CONFIG_CMD_BSP * Board specific commands
961 CONFIG_CMD_BOOTD bootd
962 CONFIG_CMD_CACHE * icache, dcache
963 CONFIG_CMD_CLK * clock command support
964 CONFIG_CMD_CONSOLE coninfo
965 CONFIG_CMD_CRC32 * crc32
966 CONFIG_CMD_DATE * support for RTC, date/time...
967 CONFIG_CMD_DHCP * DHCP support
968 CONFIG_CMD_DIAG * Diagnostics
969 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
970 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
971 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
972 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
973 CONFIG_CMD_DTT * Digital Therm and Thermostat
974 CONFIG_CMD_ECHO echo arguments
975 CONFIG_CMD_EDITENV edit env variable
976 CONFIG_CMD_EEPROM * EEPROM read/write support
977 CONFIG_CMD_ELF * bootelf, bootvx
978 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
979 CONFIG_CMD_ENV_FLAGS * display details about env flags
980 CONFIG_CMD_ENV_EXISTS * check existence of env variable
981 CONFIG_CMD_EXPORTENV * export the environment
982 CONFIG_CMD_EXT2 * ext2 command support
983 CONFIG_CMD_EXT4 * ext4 command support
984 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
985 that work for multiple fs types
986 CONFIG_CMD_SAVEENV saveenv
987 CONFIG_CMD_FDC * Floppy Disk Support
988 CONFIG_CMD_FAT * FAT command support
989 CONFIG_CMD_FLASH flinfo, erase, protect
990 CONFIG_CMD_FPGA FPGA device initialization support
991 CONFIG_CMD_FUSE * Device fuse support
992 CONFIG_CMD_GETTIME * Get time since boot
993 CONFIG_CMD_GO * the 'go' command (exec code)
994 CONFIG_CMD_GREPENV * search environment
995 CONFIG_CMD_HASH * calculate hash / digest
996 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
997 CONFIG_CMD_I2C * I2C serial bus support
998 CONFIG_CMD_IDE * IDE harddisk support
999 CONFIG_CMD_IMI iminfo
1000 CONFIG_CMD_IMLS List all images found in NOR flash
1001 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
1002 CONFIG_CMD_IMMAP * IMMR dump support
1003 CONFIG_CMD_IOTRACE * I/O tracing for debugging
1004 CONFIG_CMD_IMPORTENV * import an environment
1005 CONFIG_CMD_INI * import data from an ini file into the env
1006 CONFIG_CMD_IRQ * irqinfo
1007 CONFIG_CMD_ITEST Integer/string test of 2 values
1008 CONFIG_CMD_JFFS2 * JFFS2 Support
1009 CONFIG_CMD_KGDB * kgdb
1010 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
1011 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
1013 CONFIG_CMD_LOADB loadb
1014 CONFIG_CMD_LOADS loads
1015 CONFIG_CMD_MD5SUM * print md5 message digest
1016 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
1017 CONFIG_CMD_MEMINFO * Display detailed memory information
1018 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
1020 CONFIG_CMD_MEMTEST * mtest
1021 CONFIG_CMD_MISC Misc functions like sleep etc
1022 CONFIG_CMD_MMC * MMC memory mapped support
1023 CONFIG_CMD_MII * MII utility commands
1024 CONFIG_CMD_MTDPARTS * MTD partition support
1025 CONFIG_CMD_NAND * NAND support
1026 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1027 CONFIG_CMD_NFS NFS support
1028 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1029 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1030 CONFIG_CMD_PCI * pciinfo
1031 CONFIG_CMD_PCMCIA * PCMCIA support
1032 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1034 CONFIG_CMD_PORTIO * Port I/O
1035 CONFIG_CMD_READ * Read raw data from partition
1036 CONFIG_CMD_REGINFO * Register dump
1037 CONFIG_CMD_RUN run command in env variable
1038 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1039 CONFIG_CMD_SAVES * save S record dump
1040 CONFIG_CMD_SCSI * SCSI Support
1041 CONFIG_CMD_SDRAM * print SDRAM configuration information
1042 (requires CONFIG_CMD_I2C)
1043 CONFIG_CMD_SETGETDCR Support for DCR Register access
1045 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1046 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1047 (requires CONFIG_CMD_MEMORY)
1048 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1049 CONFIG_CMD_SOURCE "source" command Support
1050 CONFIG_CMD_SPI * SPI serial bus support
1051 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1052 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1053 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1054 CONFIG_CMD_TIMER * access to the system tick timer
1055 CONFIG_CMD_USB * USB support
1056 CONFIG_CMD_CDP * Cisco Discover Protocol support
1057 CONFIG_CMD_MFSL * Microblaze FSL support
1058 CONFIG_CMD_XIMG Load part of Multi Image
1059 CONFIG_CMD_UUID * Generate random UUID or GUID string
1061 EXAMPLE: If you want all functions except of network
1062 support you can write:
1064 #include "config_cmd_all.h"
1065 #undef CONFIG_CMD_NET
1068 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1070 Note: Don't enable the "icache" and "dcache" commands
1071 (configuration option CONFIG_CMD_CACHE) unless you know
1072 what you (and your U-Boot users) are doing. Data
1073 cache cannot be enabled on systems like the 8xx or
1074 8260 (where accesses to the IMMR region must be
1075 uncached), and it cannot be disabled on all other
1076 systems where we (mis-) use the data cache to hold an
1077 initial stack and some data.
1080 XXX - this list needs to get updated!
1082 - Regular expression support:
1084 If this variable is defined, U-Boot is linked against
1085 the SLRE (Super Light Regular Expression) library,
1086 which adds regex support to some commands, as for
1087 example "env grep" and "setexpr".
1091 If this variable is defined, U-Boot will use a device tree
1092 to configure its devices, instead of relying on statically
1093 compiled #defines in the board file. This option is
1094 experimental and only available on a few boards. The device
1095 tree is available in the global data as gd->fdt_blob.
1097 U-Boot needs to get its device tree from somewhere. This can
1098 be done using one of the two options below:
1101 If this variable is defined, U-Boot will embed a device tree
1102 binary in its image. This device tree file should be in the
1103 board directory and called <soc>-<board>.dts. The binary file
1104 is then picked up in board_init_f() and made available through
1105 the global data structure as gd->blob.
1108 If this variable is defined, U-Boot will build a device tree
1109 binary. It will be called u-boot.dtb. Architecture-specific
1110 code will locate it at run-time. Generally this works by:
1112 cat u-boot.bin u-boot.dtb >image.bin
1114 and in fact, U-Boot does this for you, creating a file called
1115 u-boot-dtb.bin which is useful in the common case. You can
1116 still use the individual files if you need something more
1121 If this variable is defined, it enables watchdog
1122 support for the SoC. There must be support in the SoC
1123 specific code for a watchdog. For the 8xx and 8260
1124 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1125 register. When supported for a specific SoC is
1126 available, then no further board specific code should
1127 be needed to use it.
1130 When using a watchdog circuitry external to the used
1131 SoC, then define this variable and provide board
1132 specific code for the "hw_watchdog_reset" function.
1135 CONFIG_VERSION_VARIABLE
1136 If this variable is defined, an environment variable
1137 named "ver" is created by U-Boot showing the U-Boot
1138 version as printed by the "version" command.
1139 Any change to this variable will be reverted at the
1144 When CONFIG_CMD_DATE is selected, the type of the RTC
1145 has to be selected, too. Define exactly one of the
1148 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1149 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1150 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1151 CONFIG_RTC_MC146818 - use MC146818 RTC
1152 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1153 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1154 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1155 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
1156 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1157 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1158 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1159 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1160 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1163 Note that if the RTC uses I2C, then the I2C interface
1164 must also be configured. See I2C Support, below.
1167 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1169 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1170 chip-ngpio pairs that tell the PCA953X driver the number of
1171 pins supported by a particular chip.
1173 Note that if the GPIO device uses I2C, then the I2C interface
1174 must also be configured. See I2C Support, below.
1177 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
1178 accesses and can checksum them or write a list of them out
1179 to memory. See the 'iotrace' command for details. This is
1180 useful for testing device drivers since it can confirm that
1181 the driver behaves the same way before and after a code
1182 change. Currently this is supported on sandbox and arm. To
1183 add support for your architecture, add '#include <iotrace.h>'
1184 to the bottom of arch/<arch>/include/asm/io.h and test.
1186 Example output from the 'iotrace stats' command is below.
1187 Note that if the trace buffer is exhausted, the checksum will
1188 still continue to operate.
1191 Start: 10000000 (buffer start address)
1192 Size: 00010000 (buffer size)
1193 Offset: 00000120 (current buffer offset)
1194 Output: 10000120 (start + offset)
1195 Count: 00000018 (number of trace records)
1196 CRC32: 9526fb66 (CRC32 of all trace records)
1198 - Timestamp Support:
1200 When CONFIG_TIMESTAMP is selected, the timestamp
1201 (date and time) of an image is printed by image
1202 commands like bootm or iminfo. This option is
1203 automatically enabled when you select CONFIG_CMD_DATE .
1205 - Partition Labels (disklabels) Supported:
1206 Zero or more of the following:
1207 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1208 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1209 Intel architecture, USB sticks, etc.
1210 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1211 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1212 bootloader. Note 2TB partition limit; see
1214 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1216 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1217 CONFIG_CMD_SCSI) you must configure support for at
1218 least one non-MTD partition type as well.
1221 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1222 board configurations files but used nowhere!
1224 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1225 be performed by calling the function
1226 ide_set_reset(int reset)
1227 which has to be defined in a board specific file
1232 Set this to enable ATAPI support.
1237 Set this to enable support for disks larger than 137GB
1238 Also look at CONFIG_SYS_64BIT_LBA.
1239 Whithout these , LBA48 support uses 32bit variables and will 'only'
1240 support disks up to 2.1TB.
1242 CONFIG_SYS_64BIT_LBA:
1243 When enabled, makes the IDE subsystem use 64bit sector addresses.
1247 At the moment only there is only support for the
1248 SYM53C8XX SCSI controller; define
1249 CONFIG_SCSI_SYM53C8XX to enable it.
1251 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1252 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1253 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1254 maximum numbers of LUNs, SCSI ID's and target
1256 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1258 The environment variable 'scsidevs' is set to the number of
1259 SCSI devices found during the last scan.
1261 - NETWORK Support (PCI):
1263 Support for Intel 8254x/8257x gigabit chips.
1266 Utility code for direct access to the SPI bus on Intel 8257x.
1267 This does not do anything useful unless you set at least one
1268 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1270 CONFIG_E1000_SPI_GENERIC
1271 Allow generic access to the SPI bus on the Intel 8257x, for
1272 example with the "sspi" command.
1275 Management command for E1000 devices. When used on devices
1276 with SPI support you can reprogram the EEPROM from U-Boot.
1278 CONFIG_E1000_FALLBACK_MAC
1279 default MAC for empty EEPROM after production.
1282 Support for Intel 82557/82559/82559ER chips.
1283 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1284 write routine for first time initialisation.
1287 Support for Digital 2114x chips.
1288 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1289 modem chip initialisation (KS8761/QS6611).
1292 Support for National dp83815 chips.
1295 Support for National dp8382[01] gigabit chips.
1297 - NETWORK Support (other):
1299 CONFIG_DRIVER_AT91EMAC
1300 Support for AT91RM9200 EMAC.
1303 Define this to use reduced MII inteface
1305 CONFIG_DRIVER_AT91EMAC_QUIET
1306 If this defined, the driver is quiet.
1307 The driver doen't show link status messages.
1309 CONFIG_CALXEDA_XGMAC
1310 Support for the Calxeda XGMAC device
1313 Support for SMSC's LAN91C96 chips.
1315 CONFIG_LAN91C96_BASE
1316 Define this to hold the physical address
1317 of the LAN91C96's I/O space
1319 CONFIG_LAN91C96_USE_32_BIT
1320 Define this to enable 32 bit addressing
1323 Support for SMSC's LAN91C111 chip
1325 CONFIG_SMC91111_BASE
1326 Define this to hold the physical address
1327 of the device (I/O space)
1329 CONFIG_SMC_USE_32_BIT
1330 Define this if data bus is 32 bits
1332 CONFIG_SMC_USE_IOFUNCS
1333 Define this to use i/o functions instead of macros
1334 (some hardware wont work with macros)
1336 CONFIG_DRIVER_TI_EMAC
1337 Support for davinci emac
1339 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1340 Define this if you have more then 3 PHYs.
1343 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1345 CONFIG_FTGMAC100_EGIGA
1346 Define this to use GE link update with gigabit PHY.
1347 Define this if FTGMAC100 is connected to gigabit PHY.
1348 If your system has 10/100 PHY only, it might not occur
1349 wrong behavior. Because PHY usually return timeout or
1350 useless data when polling gigabit status and gigabit
1351 control registers. This behavior won't affect the
1352 correctnessof 10/100 link speed update.
1355 Support for SMSC's LAN911x and LAN921x chips
1358 Define this to hold the physical address
1359 of the device (I/O space)
1361 CONFIG_SMC911X_32_BIT
1362 Define this if data bus is 32 bits
1364 CONFIG_SMC911X_16_BIT
1365 Define this if data bus is 16 bits. If your processor
1366 automatically converts one 32 bit word to two 16 bit
1367 words you may also try CONFIG_SMC911X_32_BIT.
1370 Support for Renesas on-chip Ethernet controller
1372 CONFIG_SH_ETHER_USE_PORT
1373 Define the number of ports to be used
1375 CONFIG_SH_ETHER_PHY_ADDR
1376 Define the ETH PHY's address
1378 CONFIG_SH_ETHER_CACHE_WRITEBACK
1379 If this option is set, the driver enables cache flush.
1383 Support for PWM modul on the imx6.
1387 Support TPM devices.
1390 Support for i2c bus TPM devices. Only one device
1391 per system is supported at this time.
1393 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1394 Define the the i2c bus number for the TPM device
1396 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1397 Define the TPM's address on the i2c bus
1399 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1400 Define the burst count bytes upper limit
1402 CONFIG_TPM_ATMEL_TWI
1403 Support for Atmel TWI TPM device. Requires I2C support.
1406 Support for generic parallel port TPM devices. Only one device
1407 per system is supported at this time.
1409 CONFIG_TPM_TIS_BASE_ADDRESS
1410 Base address where the generic TPM device is mapped
1411 to. Contemporary x86 systems usually map it at
1415 Add tpm monitor functions.
1416 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1417 provides monitor access to authorized functions.
1420 Define this to enable the TPM support library which provides
1421 functional interfaces to some TPM commands.
1422 Requires support for a TPM device.
1424 CONFIG_TPM_AUTH_SESSIONS
1425 Define this to enable authorized functions in the TPM library.
1426 Requires CONFIG_TPM and CONFIG_SHA1.
1429 At the moment only the UHCI host controller is
1430 supported (PIP405, MIP405, MPC5200); define
1431 CONFIG_USB_UHCI to enable it.
1432 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1433 and define CONFIG_USB_STORAGE to enable the USB
1436 Supported are USB Keyboards and USB Floppy drives
1438 MPC5200 USB requires additional defines:
1440 for 528 MHz Clock: 0x0001bbbb
1444 for differential drivers: 0x00001000
1445 for single ended drivers: 0x00005000
1446 for differential drivers on PSC3: 0x00000100
1447 for single ended drivers on PSC3: 0x00004100
1448 CONFIG_SYS_USB_EVENT_POLL
1449 May be defined to allow interrupt polling
1450 instead of using asynchronous interrupts
1452 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1453 txfilltuning field in the EHCI controller on reset.
1456 Define the below if you wish to use the USB console.
1457 Once firmware is rebuilt from a serial console issue the
1458 command "setenv stdin usbtty; setenv stdout usbtty" and
1459 attach your USB cable. The Unix command "dmesg" should print
1460 it has found a new device. The environment variable usbtty
1461 can be set to gserial or cdc_acm to enable your device to
1462 appear to a USB host as a Linux gserial device or a
1463 Common Device Class Abstract Control Model serial device.
1464 If you select usbtty = gserial you should be able to enumerate
1466 # modprobe usbserial vendor=0xVendorID product=0xProductID
1467 else if using cdc_acm, simply setting the environment
1468 variable usbtty to be cdc_acm should suffice. The following
1469 might be defined in YourBoardName.h
1472 Define this to build a UDC device
1475 Define this to have a tty type of device available to
1476 talk to the UDC device
1479 Define this to enable the high speed support for usb
1480 device and usbtty. If this feature is enabled, a routine
1481 int is_usbd_high_speed(void)
1482 also needs to be defined by the driver to dynamically poll
1483 whether the enumeration has succeded at high speed or full
1486 CONFIG_SYS_CONSOLE_IS_IN_ENV
1487 Define this if you want stdin, stdout &/or stderr to
1491 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1492 Derive USB clock from external clock "blah"
1493 - CONFIG_SYS_USB_EXTC_CLK 0x02
1495 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1496 Derive USB clock from brgclk
1497 - CONFIG_SYS_USB_BRG_CLK 0x04
1499 If you have a USB-IF assigned VendorID then you may wish to
1500 define your own vendor specific values either in BoardName.h
1501 or directly in usbd_vendor_info.h. If you don't define
1502 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1503 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1504 should pretend to be a Linux device to it's target host.
1506 CONFIG_USBD_MANUFACTURER
1507 Define this string as the name of your company for
1508 - CONFIG_USBD_MANUFACTURER "my company"
1510 CONFIG_USBD_PRODUCT_NAME
1511 Define this string as the name of your product
1512 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1514 CONFIG_USBD_VENDORID
1515 Define this as your assigned Vendor ID from the USB
1516 Implementors Forum. This *must* be a genuine Vendor ID
1517 to avoid polluting the USB namespace.
1518 - CONFIG_USBD_VENDORID 0xFFFF
1520 CONFIG_USBD_PRODUCTID
1521 Define this as the unique Product ID
1523 - CONFIG_USBD_PRODUCTID 0xFFFF
1525 - ULPI Layer Support:
1526 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1527 the generic ULPI layer. The generic layer accesses the ULPI PHY
1528 via the platform viewport, so you need both the genric layer and
1529 the viewport enabled. Currently only Chipidea/ARC based
1530 viewport is supported.
1531 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1532 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1533 If your ULPI phy needs a different reference clock than the
1534 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1535 the appropriate value in Hz.
1538 The MMC controller on the Intel PXA is supported. To
1539 enable this define CONFIG_MMC. The MMC can be
1540 accessed from the boot prompt by mapping the device
1541 to physical memory similar to flash. Command line is
1542 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1543 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1546 Support for Renesas on-chip MMCIF controller
1548 CONFIG_SH_MMCIF_ADDR
1549 Define the base address of MMCIF registers
1552 Define the clock frequency for MMCIF
1555 Enable the generic MMC driver
1557 CONFIG_SUPPORT_EMMC_BOOT
1558 Enable some additional features of the eMMC boot partitions.
1560 CONFIG_SUPPORT_EMMC_RPMB
1561 Enable the commands for reading, writing and programming the
1562 key for the Replay Protection Memory Block partition in eMMC.
1564 - USB Device Firmware Update (DFU) class support:
1566 This enables the USB portion of the DFU USB class
1569 This enables the command "dfu" which is used to have
1570 U-Boot create a DFU class device via USB. This command
1571 requires that the "dfu_alt_info" environment variable be
1572 set and define the alt settings to expose to the host.
1575 This enables support for exposing (e)MMC devices via DFU.
1578 This enables support for exposing NAND devices via DFU.
1581 This enables support for exposing RAM via DFU.
1582 Note: DFU spec refer to non-volatile memory usage, but
1583 allow usages beyond the scope of spec - here RAM usage,
1584 one that would help mostly the developer.
1586 CONFIG_SYS_DFU_DATA_BUF_SIZE
1587 Dfu transfer uses a buffer before writing data to the
1588 raw storage device. Make the size (in bytes) of this buffer
1589 configurable. The size of this buffer is also configurable
1590 through the "dfu_bufsiz" environment variable.
1592 CONFIG_SYS_DFU_MAX_FILE_SIZE
1593 When updating files rather than the raw storage device,
1594 we use a static buffer to copy the file into and then write
1595 the buffer once we've been given the whole file. Define
1596 this to the maximum filesize (in bytes) for the buffer.
1597 Default is 4 MiB if undefined.
1599 DFU_DEFAULT_POLL_TIMEOUT
1600 Poll timeout [ms], is the timeout a device can send to the
1601 host. The host must wait for this timeout before sending
1602 a subsequent DFU_GET_STATUS request to the device.
1604 DFU_MANIFEST_POLL_TIMEOUT
1605 Poll timeout [ms], which the device sends to the host when
1606 entering dfuMANIFEST state. Host waits this timeout, before
1607 sending again an USB request to the device.
1609 - USB Device Android Fastboot support:
1611 This enables the command "fastboot" which enables the Android
1612 fastboot mode for the platform's USB device. Fastboot is a USB
1613 protocol for downloading images, flashing and device control
1614 used on Android devices.
1615 See doc/README.android-fastboot for more information.
1617 CONFIG_ANDROID_BOOT_IMAGE
1618 This enables support for booting images which use the Android
1619 image format header.
1621 CONFIG_USB_FASTBOOT_BUF_ADDR
1622 The fastboot protocol requires a large memory buffer for
1623 downloads. Define this to the starting RAM address to use for
1626 CONFIG_USB_FASTBOOT_BUF_SIZE
1627 The fastboot protocol requires a large memory buffer for
1628 downloads. This buffer should be as large as possible for a
1629 platform. Define this to the size available RAM for fastboot.
1631 - Journaling Flash filesystem support:
1632 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1633 CONFIG_JFFS2_NAND_DEV
1634 Define these for a default partition on a NAND device
1636 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1637 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1638 Define these for a default partition on a NOR device
1640 CONFIG_SYS_JFFS_CUSTOM_PART
1641 Define this to create an own partition. You have to provide a
1642 function struct part_info* jffs2_part_info(int part_num)
1644 If you define only one JFFS2 partition you may also want to
1645 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1646 to disable the command chpart. This is the default when you
1647 have not defined a custom partition
1649 - FAT(File Allocation Table) filesystem write function support:
1652 Define this to enable support for saving memory data as a
1653 file in FAT formatted partition.
1655 This will also enable the command "fatwrite" enabling the
1656 user to write files to FAT.
1658 CBFS (Coreboot Filesystem) support
1661 Define this to enable support for reading from a Coreboot
1662 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1665 - FAT(File Allocation Table) filesystem cluster size:
1666 CONFIG_FS_FAT_MAX_CLUSTSIZE
1668 Define the max cluster size for fat operations else
1669 a default value of 65536 will be defined.
1674 Define this to enable standard (PC-Style) keyboard
1678 Standard PC keyboard driver with US (is default) and
1679 GERMAN key layout (switch via environment 'keymap=de') support.
1680 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1681 for cfb_console. Supports cursor blinking.
1684 Enables a Chrome OS keyboard using the CROS_EC interface.
1685 This uses CROS_EC to communicate with a second microcontroller
1686 which provides key scans on request.
1691 Define this to enable video support (for output to
1694 CONFIG_VIDEO_CT69000
1696 Enable Chips & Technologies 69000 Video chip
1698 CONFIG_VIDEO_SMI_LYNXEM
1699 Enable Silicon Motion SMI 712/710/810 Video chip. The
1700 video output is selected via environment 'videoout'
1701 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1704 For the CT69000 and SMI_LYNXEM drivers, videomode is
1705 selected via environment 'videomode'. Two different ways
1707 - "videomode=num" 'num' is a standard LiLo mode numbers.
1708 Following standard modes are supported (* is default):
1710 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1711 -------------+---------------------------------------------
1712 8 bits | 0x301* 0x303 0x305 0x161 0x307
1713 15 bits | 0x310 0x313 0x316 0x162 0x319
1714 16 bits | 0x311 0x314 0x317 0x163 0x31A
1715 24 bits | 0x312 0x315 0x318 ? 0x31B
1716 -------------+---------------------------------------------
1717 (i.e. setenv videomode 317; saveenv; reset;)
1719 - "videomode=bootargs" all the video parameters are parsed
1720 from the bootargs. (See drivers/video/videomodes.c)
1723 CONFIG_VIDEO_SED13806
1724 Enable Epson SED13806 driver. This driver supports 8bpp
1725 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1726 or CONFIG_VIDEO_SED13806_16BPP
1729 Enable the Freescale DIU video driver. Reference boards for
1730 SOCs that have a DIU should define this macro to enable DIU
1731 support, and should also define these other macros:
1737 CONFIG_VIDEO_SW_CURSOR
1738 CONFIG_VGA_AS_SINGLE_DEVICE
1740 CONFIG_VIDEO_BMP_LOGO
1742 The DIU driver will look for the 'video-mode' environment
1743 variable, and if defined, enable the DIU as a console during
1744 boot. See the documentation file README.video for a
1745 description of this variable.
1749 Enable the VGA video / BIOS for x86. The alternative if you
1750 are using coreboot is to use the coreboot frame buffer
1757 Define this to enable a custom keyboard support.
1758 This simply calls drv_keyboard_init() which must be
1759 defined in your board-specific files.
1760 The only board using this so far is RBC823.
1762 - LCD Support: CONFIG_LCD
1764 Define this to enable LCD support (for output to LCD
1765 display); also select one of the supported displays
1766 by defining one of these:
1770 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1772 CONFIG_NEC_NL6448AC33:
1774 NEC NL6448AC33-18. Active, color, single scan.
1776 CONFIG_NEC_NL6448BC20
1778 NEC NL6448BC20-08. 6.5", 640x480.
1779 Active, color, single scan.
1781 CONFIG_NEC_NL6448BC33_54
1783 NEC NL6448BC33-54. 10.4", 640x480.
1784 Active, color, single scan.
1788 Sharp 320x240. Active, color, single scan.
1789 It isn't 16x9, and I am not sure what it is.
1791 CONFIG_SHARP_LQ64D341
1793 Sharp LQ64D341 display, 640x480.
1794 Active, color, single scan.
1798 HLD1045 display, 640x480.
1799 Active, color, single scan.
1803 Optrex CBL50840-2 NF-FW 99 22 M5
1805 Hitachi LMG6912RPFC-00T
1809 320x240. Black & white.
1811 Normally display is black on white background; define
1812 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1814 CONFIG_LCD_ALIGNMENT
1816 Normally the LCD is page-aligned (tyically 4KB). If this is
1817 defined then the LCD will be aligned to this value instead.
1818 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1819 here, since it is cheaper to change data cache settings on
1820 a per-section basis.
1822 CONFIG_CONSOLE_SCROLL_LINES
1824 When the console need to be scrolled, this is the number of
1825 lines to scroll by. It defaults to 1. Increasing this makes
1826 the console jump but can help speed up operation when scrolling
1831 Support drawing of RLE8-compressed bitmaps on the LCD.
1835 Enables an 'i2c edid' command which can read EDID
1836 information over I2C from an attached LCD display.
1838 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1840 If this option is set, the environment is checked for
1841 a variable "splashimage". If found, the usual display
1842 of logo, copyright and system information on the LCD
1843 is suppressed and the BMP image at the address
1844 specified in "splashimage" is loaded instead. The
1845 console is redirected to the "nulldev", too. This
1846 allows for a "silent" boot where a splash screen is
1847 loaded very quickly after power-on.
1849 CONFIG_SPLASHIMAGE_GUARD
1851 If this option is set, then U-Boot will prevent the environment
1852 variable "splashimage" from being set to a problematic address
1853 (see README.displaying-bmps).
1854 This option is useful for targets where, due to alignment
1855 restrictions, an improperly aligned BMP image will cause a data
1856 abort. If you think you will not have problems with unaligned
1857 accesses (for example because your toolchain prevents them)
1858 there is no need to set this option.
1860 CONFIG_SPLASH_SCREEN_ALIGN
1862 If this option is set the splash image can be freely positioned
1863 on the screen. Environment variable "splashpos" specifies the
1864 position as "x,y". If a positive number is given it is used as
1865 number of pixel from left/top. If a negative number is given it
1866 is used as number of pixel from right/bottom. You can also
1867 specify 'm' for centering the image.
1870 setenv splashpos m,m
1871 => image at center of screen
1873 setenv splashpos 30,20
1874 => image at x = 30 and y = 20
1876 setenv splashpos -10,m
1877 => vertically centered image
1878 at x = dspWidth - bmpWidth - 9
1880 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1882 If this option is set, additionally to standard BMP
1883 images, gzipped BMP images can be displayed via the
1884 splashscreen support or the bmp command.
1886 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1888 If this option is set, 8-bit RLE compressed BMP images
1889 can be displayed via the splashscreen support or the
1892 - Do compresssing for memory range:
1895 If this option is set, it would use zlib deflate method
1896 to compress the specified memory at its best effort.
1898 - Compression support:
1901 Enabled by default to support gzip compressed images.
1905 If this option is set, support for bzip2 compressed
1906 images is included. If not, only uncompressed and gzip
1907 compressed images are supported.
1909 NOTE: the bzip2 algorithm requires a lot of RAM, so
1910 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1915 If this option is set, support for lzma compressed
1918 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1919 requires an amount of dynamic memory that is given by the
1922 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1924 Where lc and lp stand for, respectively, Literal context bits
1925 and Literal pos bits.
1927 This value is upper-bounded by 14MB in the worst case. Anyway,
1928 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1929 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1930 a very small buffer.
1932 Use the lzmainfo tool to determinate the lc and lp values and
1933 then calculate the amount of needed dynamic memory (ensuring
1934 the appropriate CONFIG_SYS_MALLOC_LEN value).
1938 If this option is set, support for LZO compressed images
1944 The address of PHY on MII bus.
1946 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1948 The clock frequency of the MII bus
1952 If this option is set, support for speed/duplex
1953 detection of gigabit PHY is included.
1955 CONFIG_PHY_RESET_DELAY
1957 Some PHY like Intel LXT971A need extra delay after
1958 reset before any MII register access is possible.
1959 For such PHY, set this option to the usec delay
1960 required. (minimum 300usec for LXT971A)
1962 CONFIG_PHY_CMD_DELAY (ppc4xx)
1964 Some PHY like Intel LXT971A need extra delay after
1965 command issued before MII status register can be read
1975 Define a default value for Ethernet address to use
1976 for the respective Ethernet interface, in case this
1977 is not determined automatically.
1982 Define a default value for the IP address to use for
1983 the default Ethernet interface, in case this is not
1984 determined through e.g. bootp.
1985 (Environment variable "ipaddr")
1987 - Server IP address:
1990 Defines a default value for the IP address of a TFTP
1991 server to contact when using the "tftboot" command.
1992 (Environment variable "serverip")
1994 CONFIG_KEEP_SERVERADDR
1996 Keeps the server's MAC address, in the env 'serveraddr'
1997 for passing to bootargs (like Linux's netconsole option)
1999 - Gateway IP address:
2002 Defines a default value for the IP address of the
2003 default router where packets to other networks are
2005 (Environment variable "gatewayip")
2010 Defines a default value for the subnet mask (or
2011 routing prefix) which is used to determine if an IP
2012 address belongs to the local subnet or needs to be
2013 forwarded through a router.
2014 (Environment variable "netmask")
2016 - Multicast TFTP Mode:
2019 Defines whether you want to support multicast TFTP as per
2020 rfc-2090; for example to work with atftp. Lets lots of targets
2021 tftp down the same boot image concurrently. Note: the Ethernet
2022 driver in use must provide a function: mcast() to join/leave a
2025 - BOOTP Recovery Mode:
2026 CONFIG_BOOTP_RANDOM_DELAY
2028 If you have many targets in a network that try to
2029 boot using BOOTP, you may want to avoid that all
2030 systems send out BOOTP requests at precisely the same
2031 moment (which would happen for instance at recovery
2032 from a power failure, when all systems will try to
2033 boot, thus flooding the BOOTP server. Defining
2034 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2035 inserted before sending out BOOTP requests. The
2036 following delays are inserted then:
2038 1st BOOTP request: delay 0 ... 1 sec
2039 2nd BOOTP request: delay 0 ... 2 sec
2040 3rd BOOTP request: delay 0 ... 4 sec
2042 BOOTP requests: delay 0 ... 8 sec
2044 CONFIG_BOOTP_ID_CACHE_SIZE
2046 BOOTP packets are uniquely identified using a 32-bit ID. The
2047 server will copy the ID from client requests to responses and
2048 U-Boot will use this to determine if it is the destination of
2049 an incoming response. Some servers will check that addresses
2050 aren't in use before handing them out (usually using an ARP
2051 ping) and therefore take up to a few hundred milliseconds to
2052 respond. Network congestion may also influence the time it
2053 takes for a response to make it back to the client. If that
2054 time is too long, U-Boot will retransmit requests. In order
2055 to allow earlier responses to still be accepted after these
2056 retransmissions, U-Boot's BOOTP client keeps a small cache of
2057 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2058 cache. The default is to keep IDs for up to four outstanding
2059 requests. Increasing this will allow U-Boot to accept offers
2060 from a BOOTP client in networks with unusually high latency.
2062 - DHCP Advanced Options:
2063 You can fine tune the DHCP functionality by defining
2064 CONFIG_BOOTP_* symbols:
2066 CONFIG_BOOTP_SUBNETMASK
2067 CONFIG_BOOTP_GATEWAY
2068 CONFIG_BOOTP_HOSTNAME
2069 CONFIG_BOOTP_NISDOMAIN
2070 CONFIG_BOOTP_BOOTPATH
2071 CONFIG_BOOTP_BOOTFILESIZE
2074 CONFIG_BOOTP_SEND_HOSTNAME
2075 CONFIG_BOOTP_NTPSERVER
2076 CONFIG_BOOTP_TIMEOFFSET
2077 CONFIG_BOOTP_VENDOREX
2078 CONFIG_BOOTP_MAY_FAIL
2080 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2081 environment variable, not the BOOTP server.
2083 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2084 after the configured retry count, the call will fail
2085 instead of starting over. This can be used to fail over
2086 to Link-local IP address configuration if the DHCP server
2089 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2090 serverip from a DHCP server, it is possible that more
2091 than one DNS serverip is offered to the client.
2092 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2093 serverip will be stored in the additional environment
2094 variable "dnsip2". The first DNS serverip is always
2095 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2098 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2099 to do a dynamic update of a DNS server. To do this, they
2100 need the hostname of the DHCP requester.
2101 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2102 of the "hostname" environment variable is passed as
2103 option 12 to the DHCP server.
2105 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2107 A 32bit value in microseconds for a delay between
2108 receiving a "DHCP Offer" and sending the "DHCP Request".
2109 This fixes a problem with certain DHCP servers that don't
2110 respond 100% of the time to a "DHCP request". E.g. On an
2111 AT91RM9200 processor running at 180MHz, this delay needed
2112 to be *at least* 15,000 usec before a Windows Server 2003
2113 DHCP server would reply 100% of the time. I recommend at
2114 least 50,000 usec to be safe. The alternative is to hope
2115 that one of the retries will be successful but note that
2116 the DHCP timeout and retry process takes a longer than
2119 - Link-local IP address negotiation:
2120 Negotiate with other link-local clients on the local network
2121 for an address that doesn't require explicit configuration.
2122 This is especially useful if a DHCP server cannot be guaranteed
2123 to exist in all environments that the device must operate.
2125 See doc/README.link-local for more information.
2128 CONFIG_CDP_DEVICE_ID
2130 The device id used in CDP trigger frames.
2132 CONFIG_CDP_DEVICE_ID_PREFIX
2134 A two character string which is prefixed to the MAC address
2139 A printf format string which contains the ascii name of
2140 the port. Normally is set to "eth%d" which sets
2141 eth0 for the first Ethernet, eth1 for the second etc.
2143 CONFIG_CDP_CAPABILITIES
2145 A 32bit integer which indicates the device capabilities;
2146 0x00000010 for a normal host which does not forwards.
2150 An ascii string containing the version of the software.
2154 An ascii string containing the name of the platform.
2158 A 32bit integer sent on the trigger.
2160 CONFIG_CDP_POWER_CONSUMPTION
2162 A 16bit integer containing the power consumption of the
2163 device in .1 of milliwatts.
2165 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2167 A byte containing the id of the VLAN.
2169 - Status LED: CONFIG_STATUS_LED
2171 Several configurations allow to display the current
2172 status using a LED. For instance, the LED will blink
2173 fast while running U-Boot code, stop blinking as
2174 soon as a reply to a BOOTP request was received, and
2175 start blinking slow once the Linux kernel is running
2176 (supported by a status LED driver in the Linux
2177 kernel). Defining CONFIG_STATUS_LED enables this
2183 The status LED can be connected to a GPIO pin.
2184 In such cases, the gpio_led driver can be used as a
2185 status LED backend implementation. Define CONFIG_GPIO_LED
2186 to include the gpio_led driver in the U-Boot binary.
2188 CONFIG_GPIO_LED_INVERTED_TABLE
2189 Some GPIO connected LEDs may have inverted polarity in which
2190 case the GPIO high value corresponds to LED off state and
2191 GPIO low value corresponds to LED on state.
2192 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2193 with a list of GPIO LEDs that have inverted polarity.
2195 - CAN Support: CONFIG_CAN_DRIVER
2197 Defining CONFIG_CAN_DRIVER enables CAN driver support
2198 on those systems that support this (optional)
2199 feature, like the TQM8xxL modules.
2201 - I2C Support: CONFIG_SYS_I2C
2203 This enable the NEW i2c subsystem, and will allow you to use
2204 i2c commands at the u-boot command line (as long as you set
2205 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2206 based realtime clock chips or other i2c devices. See
2207 common/cmd_i2c.c for a description of the command line
2210 ported i2c driver to the new framework:
2211 - drivers/i2c/soft_i2c.c:
2212 - activate first bus with CONFIG_SYS_I2C_SOFT define
2213 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2214 for defining speed and slave address
2215 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2216 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2217 for defining speed and slave address
2218 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2219 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2220 for defining speed and slave address
2221 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2222 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2223 for defining speed and slave address
2225 - drivers/i2c/fsl_i2c.c:
2226 - activate i2c driver with CONFIG_SYS_I2C_FSL
2227 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2228 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2229 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2231 - If your board supports a second fsl i2c bus, define
2232 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2233 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2234 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2237 - drivers/i2c/tegra_i2c.c:
2238 - activate this driver with CONFIG_SYS_I2C_TEGRA
2239 - This driver adds 4 i2c buses with a fix speed from
2240 100000 and the slave addr 0!
2242 - drivers/i2c/ppc4xx_i2c.c
2243 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2244 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2245 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2247 - drivers/i2c/i2c_mxc.c
2248 - activate this driver with CONFIG_SYS_I2C_MXC
2249 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2250 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2251 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2252 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2253 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2254 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2255 If thoses defines are not set, default value is 100000
2256 for speed, and 0 for slave.
2258 - drivers/i2c/rcar_i2c.c:
2259 - activate this driver with CONFIG_SYS_I2C_RCAR
2260 - This driver adds 4 i2c buses
2262 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2263 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2264 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2265 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2266 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2267 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2268 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2269 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2270 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2272 - drivers/i2c/sh_i2c.c:
2273 - activate this driver with CONFIG_SYS_I2C_SH
2274 - This driver adds from 2 to 5 i2c buses
2276 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2277 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2278 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2279 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2280 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2281 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2282 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2283 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2284 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2285 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2286 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2287 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2288 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2290 - drivers/i2c/omap24xx_i2c.c
2291 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2292 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2293 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2294 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2295 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2296 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2297 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2298 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2299 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2300 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2301 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2303 - drivers/i2c/zynq_i2c.c
2304 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2305 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2306 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2308 - drivers/i2c/s3c24x0_i2c.c:
2309 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2310 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2311 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2312 with a fix speed from 100000 and the slave addr 0!
2314 - drivers/i2c/ihs_i2c.c
2315 - activate this driver with CONFIG_SYS_I2C_IHS
2316 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2317 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2318 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2319 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2320 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2321 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2322 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2323 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2324 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2325 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2326 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2327 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2331 CONFIG_SYS_NUM_I2C_BUSES
2332 Hold the number of i2c busses you want to use. If you
2333 don't use/have i2c muxes on your i2c bus, this
2334 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2337 CONFIG_SYS_I2C_DIRECT_BUS
2338 define this, if you don't use i2c muxes on your hardware.
2339 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2342 CONFIG_SYS_I2C_MAX_HOPS
2343 define how many muxes are maximal consecutively connected
2344 on one i2c bus. If you not use i2c muxes, omit this
2347 CONFIG_SYS_I2C_BUSES
2348 hold a list of busses you want to use, only used if
2349 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2350 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2351 CONFIG_SYS_NUM_I2C_BUSES = 9:
2353 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2354 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2355 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2356 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2357 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2358 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2359 {1, {I2C_NULL_HOP}}, \
2360 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2361 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2365 bus 0 on adapter 0 without a mux
2366 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2367 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2368 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2369 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2370 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2371 bus 6 on adapter 1 without a mux
2372 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2373 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2375 If you do not have i2c muxes on your board, omit this define.
2377 - Legacy I2C Support: CONFIG_HARD_I2C
2379 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2380 provides the following compelling advantages:
2382 - more than one i2c adapter is usable
2383 - approved multibus support
2384 - better i2c mux support
2386 ** Please consider updating your I2C driver now. **
2388 These enable legacy I2C serial bus commands. Defining
2389 CONFIG_HARD_I2C will include the appropriate I2C driver
2390 for the selected CPU.
2392 This will allow you to use i2c commands at the u-boot
2393 command line (as long as you set CONFIG_CMD_I2C in
2394 CONFIG_COMMANDS) and communicate with i2c based realtime
2395 clock chips. See common/cmd_i2c.c for a description of the
2396 command line interface.
2398 CONFIG_HARD_I2C selects a hardware I2C controller.
2400 There are several other quantities that must also be
2401 defined when you define CONFIG_HARD_I2C.
2403 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2404 to be the frequency (in Hz) at which you wish your i2c bus
2405 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2406 the CPU's i2c node address).
2408 Now, the u-boot i2c code for the mpc8xx
2409 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2410 and so its address should therefore be cleared to 0 (See,
2411 eg, MPC823e User's Manual p.16-473). So, set
2412 CONFIG_SYS_I2C_SLAVE to 0.
2414 CONFIG_SYS_I2C_INIT_MPC5XXX
2416 When a board is reset during an i2c bus transfer
2417 chips might think that the current transfer is still
2418 in progress. Reset the slave devices by sending start
2419 commands until the slave device responds.
2421 That's all that's required for CONFIG_HARD_I2C.
2423 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2424 then the following macros need to be defined (examples are
2425 from include/configs/lwmon.h):
2429 (Optional). Any commands necessary to enable the I2C
2430 controller or configure ports.
2432 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2436 (Only for MPC8260 CPU). The I/O port to use (the code
2437 assumes both bits are on the same port). Valid values
2438 are 0..3 for ports A..D.
2442 The code necessary to make the I2C data line active
2443 (driven). If the data line is open collector, this
2446 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2450 The code necessary to make the I2C data line tri-stated
2451 (inactive). If the data line is open collector, this
2454 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2458 Code that returns true if the I2C data line is high,
2461 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2465 If <bit> is true, sets the I2C data line high. If it
2466 is false, it clears it (low).
2468 eg: #define I2C_SDA(bit) \
2469 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2470 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2474 If <bit> is true, sets the I2C clock line high. If it
2475 is false, it clears it (low).
2477 eg: #define I2C_SCL(bit) \
2478 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2479 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2483 This delay is invoked four times per clock cycle so this
2484 controls the rate of data transfer. The data rate thus
2485 is 1 / (I2C_DELAY * 4). Often defined to be something
2488 #define I2C_DELAY udelay(2)
2490 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2492 If your arch supports the generic GPIO framework (asm/gpio.h),
2493 then you may alternatively define the two GPIOs that are to be
2494 used as SCL / SDA. Any of the previous I2C_xxx macros will
2495 have GPIO-based defaults assigned to them as appropriate.
2497 You should define these to the GPIO value as given directly to
2498 the generic GPIO functions.
2500 CONFIG_SYS_I2C_INIT_BOARD
2502 When a board is reset during an i2c bus transfer
2503 chips might think that the current transfer is still
2504 in progress. On some boards it is possible to access
2505 the i2c SCLK line directly, either by using the
2506 processor pin as a GPIO or by having a second pin
2507 connected to the bus. If this option is defined a
2508 custom i2c_init_board() routine in boards/xxx/board.c
2509 is run early in the boot sequence.
2511 CONFIG_SYS_I2C_BOARD_LATE_INIT
2513 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2514 defined a custom i2c_board_late_init() routine in
2515 boards/xxx/board.c is run AFTER the operations in i2c_init()
2516 is completed. This callpoint can be used to unreset i2c bus
2517 using CPU i2c controller register accesses for CPUs whose i2c
2518 controller provide such a method. It is called at the end of
2519 i2c_init() to allow i2c_init operations to setup the i2c bus
2520 controller on the CPU (e.g. setting bus speed & slave address).
2522 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2524 This option enables configuration of bi_iic_fast[] flags
2525 in u-boot bd_info structure based on u-boot environment
2526 variable "i2cfast". (see also i2cfast)
2528 CONFIG_I2C_MULTI_BUS
2530 This option allows the use of multiple I2C buses, each of which
2531 must have a controller. At any point in time, only one bus is
2532 active. To switch to a different bus, use the 'i2c dev' command.
2533 Note that bus numbering is zero-based.
2535 CONFIG_SYS_I2C_NOPROBES
2537 This option specifies a list of I2C devices that will be skipped
2538 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2539 is set, specify a list of bus-device pairs. Otherwise, specify
2540 a 1D array of device addresses
2543 #undef CONFIG_I2C_MULTI_BUS
2544 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2546 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2548 #define CONFIG_I2C_MULTI_BUS
2549 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2551 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2553 CONFIG_SYS_SPD_BUS_NUM
2555 If defined, then this indicates the I2C bus number for DDR SPD.
2556 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2558 CONFIG_SYS_RTC_BUS_NUM
2560 If defined, then this indicates the I2C bus number for the RTC.
2561 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2563 CONFIG_SYS_DTT_BUS_NUM
2565 If defined, then this indicates the I2C bus number for the DTT.
2566 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2568 CONFIG_SYS_I2C_DTT_ADDR:
2570 If defined, specifies the I2C address of the DTT device.
2571 If not defined, then U-Boot uses predefined value for
2572 specified DTT device.
2574 CONFIG_SOFT_I2C_READ_REPEATED_START
2576 defining this will force the i2c_read() function in
2577 the soft_i2c driver to perform an I2C repeated start
2578 between writing the address pointer and reading the
2579 data. If this define is omitted the default behaviour
2580 of doing a stop-start sequence will be used. Most I2C
2581 devices can use either method, but some require one or
2584 - SPI Support: CONFIG_SPI
2586 Enables SPI driver (so far only tested with
2587 SPI EEPROM, also an instance works with Crystal A/D and
2588 D/As on the SACSng board)
2592 Enables the driver for SPI controller on SuperH. Currently
2593 only SH7757 is supported.
2597 Enables extended (16-bit) SPI EEPROM addressing.
2598 (symmetrical to CONFIG_I2C_X)
2602 Enables a software (bit-bang) SPI driver rather than
2603 using hardware support. This is a general purpose
2604 driver that only requires three general I/O port pins
2605 (two outputs, one input) to function. If this is
2606 defined, the board configuration must define several
2607 SPI configuration items (port pins to use, etc). For
2608 an example, see include/configs/sacsng.h.
2612 Enables a hardware SPI driver for general-purpose reads
2613 and writes. As with CONFIG_SOFT_SPI, the board configuration
2614 must define a list of chip-select function pointers.
2615 Currently supported on some MPC8xxx processors. For an
2616 example, see include/configs/mpc8349emds.h.
2620 Enables the driver for the SPI controllers on i.MX and MXC
2621 SoCs. Currently i.MX31/35/51 are supported.
2623 CONFIG_SYS_SPI_MXC_WAIT
2624 Timeout for waiting until spi transfer completed.
2625 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2627 - FPGA Support: CONFIG_FPGA
2629 Enables FPGA subsystem.
2631 CONFIG_FPGA_<vendor>
2633 Enables support for specific chip vendors.
2636 CONFIG_FPGA_<family>
2638 Enables support for FPGA family.
2639 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2643 Specify the number of FPGA devices to support.
2645 CONFIG_CMD_FPGA_LOADMK
2647 Enable support for fpga loadmk command
2649 CONFIG_CMD_FPGA_LOADP
2651 Enable support for fpga loadp command - load partial bitstream
2653 CONFIG_CMD_FPGA_LOADBP
2655 Enable support for fpga loadbp command - load partial bitstream
2658 CONFIG_SYS_FPGA_PROG_FEEDBACK
2660 Enable printing of hash marks during FPGA configuration.
2662 CONFIG_SYS_FPGA_CHECK_BUSY
2664 Enable checks on FPGA configuration interface busy
2665 status by the configuration function. This option
2666 will require a board or device specific function to
2671 If defined, a function that provides delays in the FPGA
2672 configuration driver.
2674 CONFIG_SYS_FPGA_CHECK_CTRLC
2675 Allow Control-C to interrupt FPGA configuration
2677 CONFIG_SYS_FPGA_CHECK_ERROR
2679 Check for configuration errors during FPGA bitfile
2680 loading. For example, abort during Virtex II
2681 configuration if the INIT_B line goes low (which
2682 indicated a CRC error).
2684 CONFIG_SYS_FPGA_WAIT_INIT
2686 Maximum time to wait for the INIT_B line to deassert
2687 after PROB_B has been deasserted during a Virtex II
2688 FPGA configuration sequence. The default time is 500
2691 CONFIG_SYS_FPGA_WAIT_BUSY
2693 Maximum time to wait for BUSY to deassert during
2694 Virtex II FPGA configuration. The default is 5 ms.
2696 CONFIG_SYS_FPGA_WAIT_CONFIG
2698 Time to wait after FPGA configuration. The default is
2701 - Configuration Management:
2704 If defined, this string will be added to the U-Boot
2705 version information (U_BOOT_VERSION)
2707 - Vendor Parameter Protection:
2709 U-Boot considers the values of the environment
2710 variables "serial#" (Board Serial Number) and
2711 "ethaddr" (Ethernet Address) to be parameters that
2712 are set once by the board vendor / manufacturer, and
2713 protects these variables from casual modification by
2714 the user. Once set, these variables are read-only,
2715 and write or delete attempts are rejected. You can
2716 change this behaviour:
2718 If CONFIG_ENV_OVERWRITE is #defined in your config
2719 file, the write protection for vendor parameters is
2720 completely disabled. Anybody can change or delete
2723 Alternatively, if you #define _both_ CONFIG_ETHADDR
2724 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2725 Ethernet address is installed in the environment,
2726 which can be changed exactly ONCE by the user. [The
2727 serial# is unaffected by this, i. e. it remains
2730 The same can be accomplished in a more flexible way
2731 for any variable by configuring the type of access
2732 to allow for those variables in the ".flags" variable
2733 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2738 Define this variable to enable the reservation of
2739 "protected RAM", i. e. RAM which is not overwritten
2740 by U-Boot. Define CONFIG_PRAM to hold the number of
2741 kB you want to reserve for pRAM. You can overwrite
2742 this default value by defining an environment
2743 variable "pram" to the number of kB you want to
2744 reserve. Note that the board info structure will
2745 still show the full amount of RAM. If pRAM is
2746 reserved, a new environment variable "mem" will
2747 automatically be defined to hold the amount of
2748 remaining RAM in a form that can be passed as boot
2749 argument to Linux, for instance like that:
2751 setenv bootargs ... mem=\${mem}
2754 This way you can tell Linux not to use this memory,
2755 either, which results in a memory region that will
2756 not be affected by reboots.
2758 *WARNING* If your board configuration uses automatic
2759 detection of the RAM size, you must make sure that
2760 this memory test is non-destructive. So far, the
2761 following board configurations are known to be
2764 IVMS8, IVML24, SPD8xx, TQM8xxL,
2765 HERMES, IP860, RPXlite, LWMON,
2768 - Access to physical memory region (> 4GB)
2769 Some basic support is provided for operations on memory not
2770 normally accessible to U-Boot - e.g. some architectures
2771 support access to more than 4GB of memory on 32-bit
2772 machines using physical address extension or similar.
2773 Define CONFIG_PHYSMEM to access this basic support, which
2774 currently only supports clearing the memory.
2779 Define this variable to stop the system in case of a
2780 fatal error, so that you have to reset it manually.
2781 This is probably NOT a good idea for an embedded
2782 system where you want the system to reboot
2783 automatically as fast as possible, but it may be
2784 useful during development since you can try to debug
2785 the conditions that lead to the situation.
2787 CONFIG_NET_RETRY_COUNT
2789 This variable defines the number of retries for
2790 network operations like ARP, RARP, TFTP, or BOOTP
2791 before giving up the operation. If not defined, a
2792 default value of 5 is used.
2796 Timeout waiting for an ARP reply in milliseconds.
2800 Timeout in milliseconds used in NFS protocol.
2801 If you encounter "ERROR: Cannot umount" in nfs command,
2802 try longer timeout such as
2803 #define CONFIG_NFS_TIMEOUT 10000UL
2805 - Command Interpreter:
2806 CONFIG_AUTO_COMPLETE
2808 Enable auto completion of commands using TAB.
2810 Note that this feature has NOT been implemented yet
2811 for the "hush" shell.
2814 CONFIG_SYS_HUSH_PARSER
2816 Define this variable to enable the "hush" shell (from
2817 Busybox) as command line interpreter, thus enabling
2818 powerful command line syntax like
2819 if...then...else...fi conditionals or `&&' and '||'
2820 constructs ("shell scripts").
2822 If undefined, you get the old, much simpler behaviour
2823 with a somewhat smaller memory footprint.
2826 CONFIG_SYS_PROMPT_HUSH_PS2
2828 This defines the secondary prompt string, which is
2829 printed when the command interpreter needs more input
2830 to complete a command. Usually "> ".
2834 In the current implementation, the local variables
2835 space and global environment variables space are
2836 separated. Local variables are those you define by
2837 simply typing `name=value'. To access a local
2838 variable later on, you have write `$name' or
2839 `${name}'; to execute the contents of a variable
2840 directly type `$name' at the command prompt.
2842 Global environment variables are those you use
2843 setenv/printenv to work with. To run a command stored
2844 in such a variable, you need to use the run command,
2845 and you must not use the '$' sign to access them.
2847 To store commands and special characters in a
2848 variable, please use double quotation marks
2849 surrounding the whole text of the variable, instead
2850 of the backslashes before semicolons and special
2853 - Commandline Editing and History:
2854 CONFIG_CMDLINE_EDITING
2856 Enable editing and History functions for interactive
2857 commandline input operations
2859 - Default Environment:
2860 CONFIG_EXTRA_ENV_SETTINGS
2862 Define this to contain any number of null terminated
2863 strings (variable = value pairs) that will be part of
2864 the default environment compiled into the boot image.
2866 For example, place something like this in your
2867 board's config file:
2869 #define CONFIG_EXTRA_ENV_SETTINGS \
2873 Warning: This method is based on knowledge about the
2874 internal format how the environment is stored by the
2875 U-Boot code. This is NOT an official, exported
2876 interface! Although it is unlikely that this format
2877 will change soon, there is no guarantee either.
2878 You better know what you are doing here.
2880 Note: overly (ab)use of the default environment is
2881 discouraged. Make sure to check other ways to preset
2882 the environment like the "source" command or the
2885 CONFIG_ENV_VARS_UBOOT_CONFIG
2887 Define this in order to add variables describing the
2888 U-Boot build configuration to the default environment.
2889 These will be named arch, cpu, board, vendor, and soc.
2891 Enabling this option will cause the following to be defined:
2899 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2901 Define this in order to add variables describing certain
2902 run-time determined information about the hardware to the
2903 environment. These will be named board_name, board_rev.
2905 CONFIG_DELAY_ENVIRONMENT
2907 Normally the environment is loaded when the board is
2908 intialised so that it is available to U-Boot. This inhibits
2909 that so that the environment is not available until
2910 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2911 this is instead controlled by the value of
2912 /config/load-environment.
2914 - DataFlash Support:
2915 CONFIG_HAS_DATAFLASH
2917 Defining this option enables DataFlash features and
2918 allows to read/write in Dataflash via the standard
2921 - Serial Flash support
2924 Defining this option enables SPI flash commands
2925 'sf probe/read/write/erase/update'.
2927 Usage requires an initial 'probe' to define the serial
2928 flash parameters, followed by read/write/erase/update
2931 The following defaults may be provided by the platform
2932 to handle the common case when only a single serial
2933 flash is present on the system.
2935 CONFIG_SF_DEFAULT_BUS Bus identifier
2936 CONFIG_SF_DEFAULT_CS Chip-select
2937 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2938 CONFIG_SF_DEFAULT_SPEED in Hz
2942 Define this option to include a destructive SPI flash
2945 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2947 Define this option to use the Bank addr/Extended addr
2948 support on SPI flashes which has size > 16Mbytes.
2950 CONFIG_SF_DUAL_FLASH Dual flash memories
2952 Define this option to use dual flash support where two flash
2953 memories can be connected with a given cs line.
2954 currently Xilinx Zynq qspi support these type of connections.
2956 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
2957 enable the W#/Vpp signal to disable writing to the status
2958 register on ST MICRON flashes like the N25Q128.
2959 The status register write enable/disable bit, combined with
2960 the W#/VPP signal provides hardware data protection for the
2961 device as follows: When the enable/disable bit is set to 1,
2962 and the W#/VPP signal is driven LOW, the status register
2963 nonvolatile bits become read-only and the WRITE STATUS REGISTER
2964 operation will not execute. The only way to exit this
2965 hardware-protected mode is to drive W#/VPP HIGH.
2967 - SystemACE Support:
2970 Adding this option adds support for Xilinx SystemACE
2971 chips attached via some sort of local bus. The address
2972 of the chip must also be defined in the
2973 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2975 #define CONFIG_SYSTEMACE
2976 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2978 When SystemACE support is added, the "ace" device type
2979 becomes available to the fat commands, i.e. fatls.
2981 - TFTP Fixed UDP Port:
2984 If this is defined, the environment variable tftpsrcp
2985 is used to supply the TFTP UDP source port value.
2986 If tftpsrcp isn't defined, the normal pseudo-random port
2987 number generator is used.
2989 Also, the environment variable tftpdstp is used to supply
2990 the TFTP UDP destination port value. If tftpdstp isn't
2991 defined, the normal port 69 is used.
2993 The purpose for tftpsrcp is to allow a TFTP server to
2994 blindly start the TFTP transfer using the pre-configured
2995 target IP address and UDP port. This has the effect of
2996 "punching through" the (Windows XP) firewall, allowing
2997 the remainder of the TFTP transfer to proceed normally.
2998 A better solution is to properly configure the firewall,
2999 but sometimes that is not allowed.
3004 This enables a generic 'hash' command which can produce
3005 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3009 Enable the hash verify command (hash -v). This adds to code
3012 CONFIG_SHA1 - support SHA1 hashing
3013 CONFIG_SHA256 - support SHA256 hashing
3015 Note: There is also a sha1sum command, which should perhaps
3016 be deprecated in favour of 'hash sha1'.
3018 - Freescale i.MX specific commands:
3019 CONFIG_CMD_HDMIDETECT
3020 This enables 'hdmidet' command which returns true if an
3021 HDMI monitor is detected. This command is i.MX 6 specific.
3024 This enables the 'bmode' (bootmode) command for forcing
3025 a boot from specific media.
3027 This is useful for forcing the ROM's usb downloader to
3028 activate upon a watchdog reset which is nice when iterating
3029 on U-Boot. Using the reset button or running bmode normal
3030 will set it back to normal. This command currently
3031 supports i.MX53 and i.MX6.
3036 This enables the RSA algorithm used for FIT image verification
3037 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
3039 The signing part is build into mkimage regardless of this
3042 - bootcount support:
3043 CONFIG_BOOTCOUNT_LIMIT
3045 This enables the bootcounter support, see:
3046 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3049 enable special bootcounter support on at91sam9xe based boards.
3051 enable special bootcounter support on blackfin based boards.
3053 enable special bootcounter support on da850 based boards.
3054 CONFIG_BOOTCOUNT_RAM
3055 enable support for the bootcounter in RAM
3056 CONFIG_BOOTCOUNT_I2C
3057 enable support for the bootcounter on an i2c (like RTC) device.
3058 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3059 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3061 CONFIG_BOOTCOUNT_ALEN = address len
3063 - Show boot progress:
3064 CONFIG_SHOW_BOOT_PROGRESS
3066 Defining this option allows to add some board-
3067 specific code (calling a user-provided function
3068 "show_boot_progress(int)") that enables you to show
3069 the system's boot progress on some display (for
3070 example, some LED's) on your board. At the moment,
3071 the following checkpoints are implemented:
3073 - Detailed boot stage timing
3075 Define this option to get detailed timing of each stage
3076 of the boot process.
3078 CONFIG_BOOTSTAGE_USER_COUNT
3079 This is the number of available user bootstage records.
3080 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
3081 a new ID will be allocated from this stash. If you exceed
3082 the limit, recording will stop.
3084 CONFIG_BOOTSTAGE_REPORT
3085 Define this to print a report before boot, similar to this:
3087 Timer summary in microseconds:
3090 3,575,678 3,575,678 board_init_f start
3091 3,575,695 17 arch_cpu_init A9
3092 3,575,777 82 arch_cpu_init done
3093 3,659,598 83,821 board_init_r start
3094 3,910,375 250,777 main_loop
3095 29,916,167 26,005,792 bootm_start
3096 30,361,327 445,160 start_kernel
3098 CONFIG_CMD_BOOTSTAGE
3099 Add a 'bootstage' command which supports printing a report
3100 and un/stashing of bootstage data.
3102 CONFIG_BOOTSTAGE_FDT
3103 Stash the bootstage information in the FDT. A root 'bootstage'
3104 node is created with each bootstage id as a child. Each child
3105 has a 'name' property and either 'mark' containing the
3106 mark time in microsecond, or 'accum' containing the
3107 accumulated time for that bootstage id in microseconds.
3112 name = "board_init_f";
3121 Code in the Linux kernel can find this in /proc/devicetree.
3123 Legacy uImage format:
3126 1 common/cmd_bootm.c before attempting to boot an image
3127 -1 common/cmd_bootm.c Image header has bad magic number
3128 2 common/cmd_bootm.c Image header has correct magic number
3129 -2 common/cmd_bootm.c Image header has bad checksum
3130 3 common/cmd_bootm.c Image header has correct checksum
3131 -3 common/cmd_bootm.c Image data has bad checksum
3132 4 common/cmd_bootm.c Image data has correct checksum
3133 -4 common/cmd_bootm.c Image is for unsupported architecture
3134 5 common/cmd_bootm.c Architecture check OK
3135 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3136 6 common/cmd_bootm.c Image Type check OK
3137 -6 common/cmd_bootm.c gunzip uncompression error
3138 -7 common/cmd_bootm.c Unimplemented compression type
3139 7 common/cmd_bootm.c Uncompression OK
3140 8 common/cmd_bootm.c No uncompress/copy overwrite error
3141 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3143 9 common/image.c Start initial ramdisk verification
3144 -10 common/image.c Ramdisk header has bad magic number
3145 -11 common/image.c Ramdisk header has bad checksum
3146 10 common/image.c Ramdisk header is OK
3147 -12 common/image.c Ramdisk data has bad checksum
3148 11 common/image.c Ramdisk data has correct checksum
3149 12 common/image.c Ramdisk verification complete, start loading
3150 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3151 13 common/image.c Start multifile image verification
3152 14 common/image.c No initial ramdisk, no multifile, continue.
3154 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3156 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3157 -31 post/post.c POST test failed, detected by post_output_backlog()
3158 -32 post/post.c POST test failed, detected by post_run_single()
3160 34 common/cmd_doc.c before loading a Image from a DOC device
3161 -35 common/cmd_doc.c Bad usage of "doc" command
3162 35 common/cmd_doc.c correct usage of "doc" command
3163 -36 common/cmd_doc.c No boot device
3164 36 common/cmd_doc.c correct boot device
3165 -37 common/cmd_doc.c Unknown Chip ID on boot device
3166 37 common/cmd_doc.c correct chip ID found, device available
3167 -38 common/cmd_doc.c Read Error on boot device
3168 38 common/cmd_doc.c reading Image header from DOC device OK
3169 -39 common/cmd_doc.c Image header has bad magic number
3170 39 common/cmd_doc.c Image header has correct magic number
3171 -40 common/cmd_doc.c Error reading Image from DOC device
3172 40 common/cmd_doc.c Image header has correct magic number
3173 41 common/cmd_ide.c before loading a Image from a IDE device
3174 -42 common/cmd_ide.c Bad usage of "ide" command
3175 42 common/cmd_ide.c correct usage of "ide" command
3176 -43 common/cmd_ide.c No boot device
3177 43 common/cmd_ide.c boot device found
3178 -44 common/cmd_ide.c Device not available
3179 44 common/cmd_ide.c Device available
3180 -45 common/cmd_ide.c wrong partition selected
3181 45 common/cmd_ide.c partition selected
3182 -46 common/cmd_ide.c Unknown partition table
3183 46 common/cmd_ide.c valid partition table found
3184 -47 common/cmd_ide.c Invalid partition type
3185 47 common/cmd_ide.c correct partition type
3186 -48 common/cmd_ide.c Error reading Image Header on boot device
3187 48 common/cmd_ide.c reading Image Header from IDE device OK
3188 -49 common/cmd_ide.c Image header has bad magic number
3189 49 common/cmd_ide.c Image header has correct magic number
3190 -50 common/cmd_ide.c Image header has bad checksum
3191 50 common/cmd_ide.c Image header has correct checksum
3192 -51 common/cmd_ide.c Error reading Image from IDE device
3193 51 common/cmd_ide.c reading Image from IDE device OK
3194 52 common/cmd_nand.c before loading a Image from a NAND device
3195 -53 common/cmd_nand.c Bad usage of "nand" command
3196 53 common/cmd_nand.c correct usage of "nand" command
3197 -54 common/cmd_nand.c No boot device
3198 54 common/cmd_nand.c boot device found
3199 -55 common/cmd_nand.c Unknown Chip ID on boot device
3200 55 common/cmd_nand.c correct chip ID found, device available
3201 -56 common/cmd_nand.c Error reading Image Header on boot device
3202 56 common/cmd_nand.c reading Image Header from NAND device OK
3203 -57 common/cmd_nand.c Image header has bad magic number
3204 57 common/cmd_nand.c Image header has correct magic number
3205 -58 common/cmd_nand.c Error reading Image from NAND device
3206 58 common/cmd_nand.c reading Image from NAND device OK
3208 -60 common/env_common.c Environment has a bad CRC, using default
3210 64 net/eth.c starting with Ethernet configuration.
3211 -64 net/eth.c no Ethernet found.
3212 65 net/eth.c Ethernet found.
3214 -80 common/cmd_net.c usage wrong
3215 80 common/cmd_net.c before calling NetLoop()
3216 -81 common/cmd_net.c some error in NetLoop() occurred
3217 81 common/cmd_net.c NetLoop() back without error
3218 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3219 82 common/cmd_net.c trying automatic boot
3220 83 common/cmd_net.c running "source" command
3221 -83 common/cmd_net.c some error in automatic boot or "source" command
3222 84 common/cmd_net.c end without errors
3227 100 common/cmd_bootm.c Kernel FIT Image has correct format
3228 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3229 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3230 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3231 102 common/cmd_bootm.c Kernel unit name specified
3232 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3233 103 common/cmd_bootm.c Found configuration node
3234 104 common/cmd_bootm.c Got kernel subimage node offset
3235 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3236 105 common/cmd_bootm.c Kernel subimage hash verification OK
3237 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3238 106 common/cmd_bootm.c Architecture check OK
3239 -106 common/cmd_bootm.c Kernel subimage has wrong type
3240 107 common/cmd_bootm.c Kernel subimage type OK
3241 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3242 108 common/cmd_bootm.c Got kernel subimage data/size
3243 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3244 -109 common/cmd_bootm.c Can't get kernel subimage type
3245 -110 common/cmd_bootm.c Can't get kernel subimage comp
3246 -111 common/cmd_bootm.c Can't get kernel subimage os
3247 -112 common/cmd_bootm.c Can't get kernel subimage load address
3248 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3250 120 common/image.c Start initial ramdisk verification
3251 -120 common/image.c Ramdisk FIT image has incorrect format
3252 121 common/image.c Ramdisk FIT image has correct format
3253 122 common/image.c No ramdisk subimage unit name, using configuration
3254 -122 common/image.c Can't get configuration for ramdisk subimage
3255 123 common/image.c Ramdisk unit name specified
3256 -124 common/image.c Can't get ramdisk subimage node offset
3257 125 common/image.c Got ramdisk subimage node offset
3258 -125 common/image.c Ramdisk subimage hash verification failed
3259 126 common/image.c Ramdisk subimage hash verification OK
3260 -126 common/image.c Ramdisk subimage for unsupported architecture
3261 127 common/image.c Architecture check OK
3262 -127 common/image.c Can't get ramdisk subimage data/size
3263 128 common/image.c Got ramdisk subimage data/size
3264 129 common/image.c Can't get ramdisk load address
3265 -129 common/image.c Got ramdisk load address
3267 -130 common/cmd_doc.c Incorrect FIT image format
3268 131 common/cmd_doc.c FIT image format OK
3270 -140 common/cmd_ide.c Incorrect FIT image format
3271 141 common/cmd_ide.c FIT image format OK
3273 -150 common/cmd_nand.c Incorrect FIT image format
3274 151 common/cmd_nand.c FIT image format OK
3276 - legacy image format:
3277 CONFIG_IMAGE_FORMAT_LEGACY
3278 enables the legacy image format support in U-Boot.
3281 enabled if CONFIG_FIT_SIGNATURE is not defined.
3283 CONFIG_DISABLE_IMAGE_LEGACY
3284 disable the legacy image format
3286 This define is introduced, as the legacy image format is
3287 enabled per default for backward compatibility.
3289 - FIT image support:
3291 Enable support for the FIT uImage format.
3293 CONFIG_FIT_BEST_MATCH
3294 When no configuration is explicitly selected, default to the
3295 one whose fdt's compatibility field best matches that of
3296 U-Boot itself. A match is considered "best" if it matches the
3297 most specific compatibility entry of U-Boot's fdt's root node.
3298 The order of entries in the configuration's fdt is ignored.
3300 CONFIG_FIT_SIGNATURE
3301 This option enables signature verification of FIT uImages,
3302 using a hash signed and verified using RSA. See
3303 doc/uImage.FIT/signature.txt for more details.
3305 WARNING: When relying on signed FIT images with required
3306 signature check the legacy image format is default
3307 disabled. If a board need legacy image format support
3308 enable this through CONFIG_IMAGE_FORMAT_LEGACY
3310 CONFIG_FIT_DISABLE_SHA256
3311 Supporting SHA256 hashes has quite an impact on binary size.
3312 For constrained systems sha256 hash support can be disabled
3315 - Standalone program support:
3316 CONFIG_STANDALONE_LOAD_ADDR
3318 This option defines a board specific value for the
3319 address where standalone program gets loaded, thus
3320 overwriting the architecture dependent default
3323 - Frame Buffer Address:
3326 Define CONFIG_FB_ADDR if you want to use specific
3327 address for frame buffer. This is typically the case
3328 when using a graphics controller has separate video
3329 memory. U-Boot will then place the frame buffer at
3330 the given address instead of dynamically reserving it
3331 in system RAM by calling lcd_setmem(), which grabs
3332 the memory for the frame buffer depending on the
3333 configured panel size.
3335 Please see board_init_f function.
3337 - Automatic software updates via TFTP server
3339 CONFIG_UPDATE_TFTP_CNT_MAX
3340 CONFIG_UPDATE_TFTP_MSEC_MAX
3342 These options enable and control the auto-update feature;
3343 for a more detailed description refer to doc/README.update.
3345 - MTD Support (mtdparts command, UBI support)
3348 Adds the MTD device infrastructure from the Linux kernel.
3349 Needed for mtdparts command support.
3351 CONFIG_MTD_PARTITIONS
3353 Adds the MTD partitioning infrastructure from the Linux
3354 kernel. Needed for UBI support.
3356 CONFIG_MTD_NAND_VERIFY_WRITE
3357 verify if the written data is correct reread.
3362 Adds commands for interacting with MTD partitions formatted
3363 with the UBI flash translation layer
3365 Requires also defining CONFIG_RBTREE
3367 CONFIG_UBI_SILENCE_MSG
3369 Make the verbose messages from UBI stop printing. This leaves
3370 warnings and errors enabled.
3373 CONFIG_MTD_UBI_WL_THRESHOLD
3374 This parameter defines the maximum difference between the highest
3375 erase counter value and the lowest erase counter value of eraseblocks
3376 of UBI devices. When this threshold is exceeded, UBI starts performing
3377 wear leveling by means of moving data from eraseblock with low erase
3378 counter to eraseblocks with high erase counter.
3380 The default value should be OK for SLC NAND flashes, NOR flashes and
3381 other flashes which have eraseblock life-cycle 100000 or more.
3382 However, in case of MLC NAND flashes which typically have eraseblock
3383 life-cycle less than 10000, the threshold should be lessened (e.g.,
3384 to 128 or 256, although it does not have to be power of 2).
3388 CONFIG_MTD_UBI_BEB_LIMIT
3389 This option specifies the maximum bad physical eraseblocks UBI
3390 expects on the MTD device (per 1024 eraseblocks). If the
3391 underlying flash does not admit of bad eraseblocks (e.g. NOR
3392 flash), this value is ignored.
3394 NAND datasheets often specify the minimum and maximum NVM
3395 (Number of Valid Blocks) for the flashes' endurance lifetime.
3396 The maximum expected bad eraseblocks per 1024 eraseblocks
3397 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3398 which gives 20 for most NANDs (MaxNVB is basically the total
3399 count of eraseblocks on the chip).
3401 To put it differently, if this value is 20, UBI will try to
3402 reserve about 1.9% of physical eraseblocks for bad blocks
3403 handling. And that will be 1.9% of eraseblocks on the entire
3404 NAND chip, not just the MTD partition UBI attaches. This means
3405 that if you have, say, a NAND flash chip admits maximum 40 bad
3406 eraseblocks, and it is split on two MTD partitions of the same
3407 size, UBI will reserve 40 eraseblocks when attaching a
3412 CONFIG_MTD_UBI_FASTMAP
3413 Fastmap is a mechanism which allows attaching an UBI device
3414 in nearly constant time. Instead of scanning the whole MTD device it
3415 only has to locate a checkpoint (called fastmap) on the device.
3416 The on-flash fastmap contains all information needed to attach
3417 the device. Using fastmap makes only sense on large devices where
3418 attaching by scanning takes long. UBI will not automatically install
3419 a fastmap on old images, but you can set the UBI parameter
3420 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3421 that fastmap-enabled images are still usable with UBI implementations
3422 without fastmap support. On typical flash devices the whole fastmap
3423 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3425 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3426 Set this parameter to enable fastmap automatically on images
3433 Adds commands for interacting with UBI volumes formatted as
3434 UBIFS. UBIFS is read-only in u-boot.
3436 Requires UBI support as well as CONFIG_LZO
3438 CONFIG_UBIFS_SILENCE_MSG
3440 Make the verbose messages from UBIFS stop printing. This leaves
3441 warnings and errors enabled.
3445 Enable building of SPL globally.
3448 LDSCRIPT for linking the SPL binary.
3450 CONFIG_SPL_MAX_FOOTPRINT
3451 Maximum size in memory allocated to the SPL, BSS included.
3452 When defined, the linker checks that the actual memory
3453 used by SPL from _start to __bss_end does not exceed it.
3454 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3455 must not be both defined at the same time.
3458 Maximum size of the SPL image (text, data, rodata, and
3459 linker lists sections), BSS excluded.
3460 When defined, the linker checks that the actual size does
3463 CONFIG_SPL_TEXT_BASE
3464 TEXT_BASE for linking the SPL binary.
3466 CONFIG_SPL_RELOC_TEXT_BASE
3467 Address to relocate to. If unspecified, this is equal to
3468 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3470 CONFIG_SPL_BSS_START_ADDR
3471 Link address for the BSS within the SPL binary.
3473 CONFIG_SPL_BSS_MAX_SIZE
3474 Maximum size in memory allocated to the SPL BSS.
3475 When defined, the linker checks that the actual memory used
3476 by SPL from __bss_start to __bss_end does not exceed it.
3477 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3478 must not be both defined at the same time.
3481 Adress of the start of the stack SPL will use
3483 CONFIG_SPL_RELOC_STACK
3484 Adress of the start of the stack SPL will use after
3485 relocation. If unspecified, this is equal to
3488 CONFIG_SYS_SPL_MALLOC_START
3489 Starting address of the malloc pool used in SPL.
3491 CONFIG_SYS_SPL_MALLOC_SIZE
3492 The size of the malloc pool used in SPL.
3494 CONFIG_SPL_FRAMEWORK
3495 Enable the SPL framework under common/. This framework
3496 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3497 NAND loading of the Linux Kernel.
3500 Enable booting directly to an OS from SPL.
3501 See also: doc/README.falcon
3503 CONFIG_SPL_DISPLAY_PRINT
3504 For ARM, enable an optional function to print more information
3505 about the running system.
3507 CONFIG_SPL_INIT_MINIMAL
3508 Arch init code should be built for a very small image
3510 CONFIG_SPL_LIBCOMMON_SUPPORT
3511 Support for common/libcommon.o in SPL binary
3513 CONFIG_SPL_LIBDISK_SUPPORT
3514 Support for disk/libdisk.o in SPL binary
3516 CONFIG_SPL_I2C_SUPPORT
3517 Support for drivers/i2c/libi2c.o in SPL binary
3519 CONFIG_SPL_GPIO_SUPPORT
3520 Support for drivers/gpio/libgpio.o in SPL binary
3522 CONFIG_SPL_MMC_SUPPORT
3523 Support for drivers/mmc/libmmc.o in SPL binary
3525 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3526 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3527 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3528 Address, size and partition on the MMC to load U-Boot from
3529 when the MMC is being used in raw mode.
3531 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3532 Sector to load kernel uImage from when MMC is being
3533 used in raw mode (for Falcon mode)
3535 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3536 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3537 Sector and number of sectors to load kernel argument
3538 parameters from when MMC is being used in raw mode
3541 CONFIG_SPL_FAT_SUPPORT
3542 Support for fs/fat/libfat.o in SPL binary
3544 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3545 Filename to read to load U-Boot when reading from FAT
3547 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3548 Filename to read to load kernel uImage when reading
3549 from FAT (for Falcon mode)
3551 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3552 Filename to read to load kernel argument parameters
3553 when reading from FAT (for Falcon mode)
3555 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3556 Set this for NAND SPL on PPC mpc83xx targets, so that
3557 start.S waits for the rest of the SPL to load before
3558 continuing (the hardware starts execution after just
3559 loading the first page rather than the full 4K).
3561 CONFIG_SPL_SKIP_RELOCATE
3562 Avoid SPL relocation
3564 CONFIG_SPL_NAND_BASE
3565 Include nand_base.c in the SPL. Requires
3566 CONFIG_SPL_NAND_DRIVERS.
3568 CONFIG_SPL_NAND_DRIVERS
3569 SPL uses normal NAND drivers, not minimal drivers.
3572 Include standard software ECC in the SPL
3574 CONFIG_SPL_NAND_SIMPLE
3575 Support for NAND boot using simple NAND drivers that
3576 expose the cmd_ctrl() interface.
3578 CONFIG_SPL_MTD_SUPPORT
3579 Support for the MTD subsystem within SPL. Useful for
3580 environment on NAND support within SPL.
3582 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3583 Set for the SPL on PPC mpc8xxx targets, support for
3584 drivers/ddr/fsl/libddr.o in SPL binary.
3586 CONFIG_SPL_COMMON_INIT_DDR
3587 Set for common ddr init with serial presence detect in
3590 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3591 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3592 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3593 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3594 CONFIG_SYS_NAND_ECCBYTES
3595 Defines the size and behavior of the NAND that SPL uses
3598 CONFIG_SPL_NAND_BOOT
3599 Add support NAND boot
3601 CONFIG_SYS_NAND_U_BOOT_OFFS
3602 Location in NAND to read U-Boot from
3604 CONFIG_SYS_NAND_U_BOOT_DST
3605 Location in memory to load U-Boot to
3607 CONFIG_SYS_NAND_U_BOOT_SIZE
3608 Size of image to load
3610 CONFIG_SYS_NAND_U_BOOT_START
3611 Entry point in loaded image to jump to
3613 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3614 Define this if you need to first read the OOB and then the
3615 data. This is used for example on davinci plattforms.
3617 CONFIG_SPL_OMAP3_ID_NAND
3618 Support for an OMAP3-specific set of functions to return the
3619 ID and MFR of the first attached NAND chip, if present.
3621 CONFIG_SPL_SERIAL_SUPPORT
3622 Support for drivers/serial/libserial.o in SPL binary
3624 CONFIG_SPL_SPI_FLASH_SUPPORT
3625 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3627 CONFIG_SPL_SPI_SUPPORT
3628 Support for drivers/spi/libspi.o in SPL binary
3630 CONFIG_SPL_RAM_DEVICE
3631 Support for running image already present in ram, in SPL binary
3633 CONFIG_SPL_LIBGENERIC_SUPPORT
3634 Support for lib/libgeneric.o in SPL binary
3636 CONFIG_SPL_ENV_SUPPORT
3637 Support for the environment operating in SPL binary
3639 CONFIG_SPL_NET_SUPPORT
3640 Support for the net/libnet.o in SPL binary.
3641 It conflicts with SPL env from storage medium specified by
3642 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3645 Image offset to which the SPL should be padded before appending
3646 the SPL payload. By default, this is defined as
3647 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3648 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3649 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3652 Final target image containing SPL and payload. Some SPLs
3653 use an arch-specific makefile fragment instead, for
3654 example if more than one image needs to be produced.
3656 CONFIG_FIT_SPL_PRINT
3657 Printing information about a FIT image adds quite a bit of
3658 code to SPL. So this is normally disabled in SPL. Use this
3659 option to re-enable it. This will affect the output of the
3660 bootm command when booting a FIT image.
3664 Enable building of TPL globally.
3667 Image offset to which the TPL should be padded before appending
3668 the TPL payload. By default, this is defined as
3669 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3670 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3671 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3676 [so far only for SMDK2400 boards]
3678 - Modem support enable:
3679 CONFIG_MODEM_SUPPORT
3681 - RTS/CTS Flow control enable:
3684 - Modem debug support:
3685 CONFIG_MODEM_SUPPORT_DEBUG
3687 Enables debugging stuff (char screen[1024], dbg())
3688 for modem support. Useful only with BDI2000.
3690 - Interrupt support (PPC):
3692 There are common interrupt_init() and timer_interrupt()
3693 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3694 for CPU specific initialization. interrupt_init_cpu()
3695 should set decrementer_count to appropriate value. If
3696 CPU resets decrementer automatically after interrupt
3697 (ppc4xx) it should set decrementer_count to zero.
3698 timer_interrupt() calls timer_interrupt_cpu() for CPU
3699 specific handling. If board has watchdog / status_led
3700 / other_activity_monitor it works automatically from
3701 general timer_interrupt().
3705 In the target system modem support is enabled when a
3706 specific key (key combination) is pressed during
3707 power-on. Otherwise U-Boot will boot normally
3708 (autoboot). The key_pressed() function is called from
3709 board_init(). Currently key_pressed() is a dummy
3710 function, returning 1 and thus enabling modem
3713 If there are no modem init strings in the
3714 environment, U-Boot proceed to autoboot; the
3715 previous output (banner, info printfs) will be
3718 See also: doc/README.Modem
3720 Board initialization settings:
3721 ------------------------------
3723 During Initialization u-boot calls a number of board specific functions
3724 to allow the preparation of board specific prerequisites, e.g. pin setup
3725 before drivers are initialized. To enable these callbacks the
3726 following configuration macros have to be defined. Currently this is
3727 architecture specific, so please check arch/your_architecture/lib/board.c
3728 typically in board_init_f() and board_init_r().
3730 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3731 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3732 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3733 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3735 Configuration Settings:
3736 -----------------------
3738 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3739 Optionally it can be defined to support 64-bit memory commands.
3741 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3742 undefine this when you're short of memory.
3744 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3745 width of the commands listed in the 'help' command output.
3747 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3748 prompt for user input.
3750 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3752 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3754 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3756 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3757 the application (usually a Linux kernel) when it is
3760 - CONFIG_SYS_BAUDRATE_TABLE:
3761 List of legal baudrate settings for this board.
3763 - CONFIG_SYS_CONSOLE_INFO_QUIET
3764 Suppress display of console information at boot.
3766 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3767 If the board specific function
3768 extern int overwrite_console (void);
3769 returns 1, the stdin, stderr and stdout are switched to the
3770 serial port, else the settings in the environment are used.
3772 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3773 Enable the call to overwrite_console().
3775 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3776 Enable overwrite of previous console environment settings.
3778 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3779 Begin and End addresses of the area used by the
3782 - CONFIG_SYS_ALT_MEMTEST:
3783 Enable an alternate, more extensive memory test.
3785 - CONFIG_SYS_MEMTEST_SCRATCH:
3786 Scratch address used by the alternate memory test
3787 You only need to set this if address zero isn't writeable
3789 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3790 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3791 this specified memory area will get subtracted from the top
3792 (end) of RAM and won't get "touched" at all by U-Boot. By
3793 fixing up gd->ram_size the Linux kernel should gets passed
3794 the now "corrected" memory size and won't touch it either.
3795 This should work for arch/ppc and arch/powerpc. Only Linux
3796 board ports in arch/powerpc with bootwrapper support that
3797 recalculate the memory size from the SDRAM controller setup
3798 will have to get fixed in Linux additionally.
3800 This option can be used as a workaround for the 440EPx/GRx
3801 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3804 WARNING: Please make sure that this value is a multiple of
3805 the Linux page size (normally 4k). If this is not the case,
3806 then the end address of the Linux memory will be located at a
3807 non page size aligned address and this could cause major
3810 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3811 Enable temporary baudrate change while serial download
3813 - CONFIG_SYS_SDRAM_BASE:
3814 Physical start address of SDRAM. _Must_ be 0 here.
3816 - CONFIG_SYS_MBIO_BASE:
3817 Physical start address of Motherboard I/O (if using a
3820 - CONFIG_SYS_FLASH_BASE:
3821 Physical start address of Flash memory.
3823 - CONFIG_SYS_MONITOR_BASE:
3824 Physical start address of boot monitor code (set by
3825 make config files to be same as the text base address
3826 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3827 CONFIG_SYS_FLASH_BASE when booting from flash.
3829 - CONFIG_SYS_MONITOR_LEN:
3830 Size of memory reserved for monitor code, used to
3831 determine _at_compile_time_ (!) if the environment is
3832 embedded within the U-Boot image, or in a separate
3835 - CONFIG_SYS_MALLOC_LEN:
3836 Size of DRAM reserved for malloc() use.
3838 - CONFIG_SYS_MALLOC_F_LEN
3839 Size of the malloc() pool for use before relocation. If
3840 this is defined, then a very simple malloc() implementation
3841 will become available before relocation. The address is just
3842 below the global data, and the stack is moved down to make
3845 This feature allocates regions with increasing addresses
3846 within the region. calloc() is supported, but realloc()
3847 is not available. free() is supported but does nothing.
3848 The memory will be freed (or in fact just forgotton) when
3849 U-Boot relocates itself.
3851 Pre-relocation malloc() is only supported on sandbox
3852 at present but is fairly easy to enable for other archs.
3854 Pre-relocation malloc() is only supported on ARM at present
3855 but is fairly easy to enable for other archs.
3857 - CONFIG_SYS_BOOTM_LEN:
3858 Normally compressed uImages are limited to an
3859 uncompressed size of 8 MBytes. If this is not enough,
3860 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3861 to adjust this setting to your needs.
3863 - CONFIG_SYS_BOOTMAPSZ:
3864 Maximum size of memory mapped by the startup code of
3865 the Linux kernel; all data that must be processed by
3866 the Linux kernel (bd_info, boot arguments, FDT blob if
3867 used) must be put below this limit, unless "bootm_low"
3868 environment variable is defined and non-zero. In such case
3869 all data for the Linux kernel must be between "bootm_low"
3870 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3871 variable "bootm_mapsize" will override the value of
3872 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3873 then the value in "bootm_size" will be used instead.
3875 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3876 Enable initrd_high functionality. If defined then the
3877 initrd_high feature is enabled and the bootm ramdisk subcommand
3880 - CONFIG_SYS_BOOT_GET_CMDLINE:
3881 Enables allocating and saving kernel cmdline in space between
3882 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3884 - CONFIG_SYS_BOOT_GET_KBD:
3885 Enables allocating and saving a kernel copy of the bd_info in
3886 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3888 - CONFIG_SYS_MAX_FLASH_BANKS:
3889 Max number of Flash memory banks
3891 - CONFIG_SYS_MAX_FLASH_SECT:
3892 Max number of sectors on a Flash chip
3894 - CONFIG_SYS_FLASH_ERASE_TOUT:
3895 Timeout for Flash erase operations (in ms)
3897 - CONFIG_SYS_FLASH_WRITE_TOUT:
3898 Timeout for Flash write operations (in ms)
3900 - CONFIG_SYS_FLASH_LOCK_TOUT
3901 Timeout for Flash set sector lock bit operation (in ms)
3903 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3904 Timeout for Flash clear lock bits operation (in ms)
3906 - CONFIG_SYS_FLASH_PROTECTION
3907 If defined, hardware flash sectors protection is used
3908 instead of U-Boot software protection.
3910 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3912 Enable TFTP transfers directly to flash memory;
3913 without this option such a download has to be
3914 performed in two steps: (1) download to RAM, and (2)
3915 copy from RAM to flash.
3917 The two-step approach is usually more reliable, since
3918 you can check if the download worked before you erase
3919 the flash, but in some situations (when system RAM is
3920 too limited to allow for a temporary copy of the
3921 downloaded image) this option may be very useful.
3923 - CONFIG_SYS_FLASH_CFI:
3924 Define if the flash driver uses extra elements in the
3925 common flash structure for storing flash geometry.
3927 - CONFIG_FLASH_CFI_DRIVER
3928 This option also enables the building of the cfi_flash driver
3929 in the drivers directory
3931 - CONFIG_FLASH_CFI_MTD
3932 This option enables the building of the cfi_mtd driver
3933 in the drivers directory. The driver exports CFI flash
3936 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3937 Use buffered writes to flash.
3939 - CONFIG_FLASH_SPANSION_S29WS_N
3940 s29ws-n MirrorBit flash has non-standard addresses for buffered
3943 - CONFIG_SYS_FLASH_QUIET_TEST
3944 If this option is defined, the common CFI flash doesn't
3945 print it's warning upon not recognized FLASH banks. This
3946 is useful, if some of the configured banks are only
3947 optionally available.
3949 - CONFIG_FLASH_SHOW_PROGRESS
3950 If defined (must be an integer), print out countdown
3951 digits and dots. Recommended value: 45 (9..1) for 80
3952 column displays, 15 (3..1) for 40 column displays.
3954 - CONFIG_FLASH_VERIFY
3955 If defined, the content of the flash (destination) is compared
3956 against the source after the write operation. An error message
3957 will be printed when the contents are not identical.
3958 Please note that this option is useless in nearly all cases,
3959 since such flash programming errors usually are detected earlier
3960 while unprotecting/erasing/programming. Please only enable
3961 this option if you really know what you are doing.
3963 - CONFIG_SYS_RX_ETH_BUFFER:
3964 Defines the number of Ethernet receive buffers. On some
3965 Ethernet controllers it is recommended to set this value
3966 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3967 buffers can be full shortly after enabling the interface
3968 on high Ethernet traffic.
3969 Defaults to 4 if not defined.
3971 - CONFIG_ENV_MAX_ENTRIES
3973 Maximum number of entries in the hash table that is used
3974 internally to store the environment settings. The default
3975 setting is supposed to be generous and should work in most
3976 cases. This setting can be used to tune behaviour; see
3977 lib/hashtable.c for details.
3979 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3980 - CONFIG_ENV_FLAGS_LIST_STATIC
3981 Enable validation of the values given to environment variables when
3982 calling env set. Variables can be restricted to only decimal,
3983 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3984 the variables can also be restricted to IP address or MAC address.
3986 The format of the list is:
3987 type_attribute = [s|d|x|b|i|m]
3988 access_atribute = [a|r|o|c]
3989 attributes = type_attribute[access_atribute]
3990 entry = variable_name[:attributes]
3993 The type attributes are:
3994 s - String (default)
3997 b - Boolean ([1yYtT|0nNfF])
4001 The access attributes are:
4007 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4008 Define this to a list (string) to define the ".flags"
4009 envirnoment variable in the default or embedded environment.
4011 - CONFIG_ENV_FLAGS_LIST_STATIC
4012 Define this to a list (string) to define validation that
4013 should be done if an entry is not found in the ".flags"
4014 environment variable. To override a setting in the static
4015 list, simply add an entry for the same variable name to the
4018 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4019 If defined, don't allow the -f switch to env set override variable
4022 - CONFIG_SYS_GENERIC_BOARD
4023 This selects the architecture-generic board system instead of the
4024 architecture-specific board files. It is intended to move boards
4025 to this new framework over time. Defining this will disable the
4026 arch/foo/lib/board.c file and use common/board_f.c and
4027 common/board_r.c instead. To use this option your architecture
4028 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
4029 its config.mk file). If you find problems enabling this option on
4030 your board please report the problem and send patches!
4032 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4033 This is set by OMAP boards for the max time that reset should
4034 be asserted. See doc/README.omap-reset-time for details on how
4035 the value can be calulated on a given board.
4037 The following definitions that deal with the placement and management
4038 of environment data (variable area); in general, we support the
4039 following configurations:
4041 - CONFIG_BUILD_ENVCRC:
4043 Builds up envcrc with the target environment so that external utils
4044 may easily extract it and embed it in final U-Boot images.
4046 - CONFIG_ENV_IS_IN_FLASH:
4048 Define this if the environment is in flash memory.
4050 a) The environment occupies one whole flash sector, which is
4051 "embedded" in the text segment with the U-Boot code. This
4052 happens usually with "bottom boot sector" or "top boot
4053 sector" type flash chips, which have several smaller
4054 sectors at the start or the end. For instance, such a
4055 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4056 such a case you would place the environment in one of the
4057 4 kB sectors - with U-Boot code before and after it. With
4058 "top boot sector" type flash chips, you would put the
4059 environment in one of the last sectors, leaving a gap
4060 between U-Boot and the environment.
4062 - CONFIG_ENV_OFFSET:
4064 Offset of environment data (variable area) to the
4065 beginning of flash memory; for instance, with bottom boot
4066 type flash chips the second sector can be used: the offset
4067 for this sector is given here.
4069 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4073 This is just another way to specify the start address of
4074 the flash sector containing the environment (instead of
4077 - CONFIG_ENV_SECT_SIZE:
4079 Size of the sector containing the environment.
4082 b) Sometimes flash chips have few, equal sized, BIG sectors.
4083 In such a case you don't want to spend a whole sector for
4088 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4089 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4090 of this flash sector for the environment. This saves
4091 memory for the RAM copy of the environment.
4093 It may also save flash memory if you decide to use this
4094 when your environment is "embedded" within U-Boot code,
4095 since then the remainder of the flash sector could be used
4096 for U-Boot code. It should be pointed out that this is
4097 STRONGLY DISCOURAGED from a robustness point of view:
4098 updating the environment in flash makes it always
4099 necessary to erase the WHOLE sector. If something goes
4100 wrong before the contents has been restored from a copy in
4101 RAM, your target system will be dead.
4103 - CONFIG_ENV_ADDR_REDUND
4104 CONFIG_ENV_SIZE_REDUND
4106 These settings describe a second storage area used to hold
4107 a redundant copy of the environment data, so that there is
4108 a valid backup copy in case there is a power failure during
4109 a "saveenv" operation.
4111 BE CAREFUL! Any changes to the flash layout, and some changes to the
4112 source code will make it necessary to adapt <board>/u-boot.lds*
4116 - CONFIG_ENV_IS_IN_NVRAM:
4118 Define this if you have some non-volatile memory device
4119 (NVRAM, battery buffered SRAM) which you want to use for the
4125 These two #defines are used to determine the memory area you
4126 want to use for environment. It is assumed that this memory
4127 can just be read and written to, without any special
4130 BE CAREFUL! The first access to the environment happens quite early
4131 in U-Boot initalization (when we try to get the setting of for the
4132 console baudrate). You *MUST* have mapped your NVRAM area then, or
4135 Please note that even with NVRAM we still use a copy of the
4136 environment in RAM: we could work on NVRAM directly, but we want to
4137 keep settings there always unmodified except somebody uses "saveenv"
4138 to save the current settings.
4141 - CONFIG_ENV_IS_IN_EEPROM:
4143 Use this if you have an EEPROM or similar serial access
4144 device and a driver for it.
4146 - CONFIG_ENV_OFFSET:
4149 These two #defines specify the offset and size of the
4150 environment area within the total memory of your EEPROM.
4152 - CONFIG_SYS_I2C_EEPROM_ADDR:
4153 If defined, specified the chip address of the EEPROM device.
4154 The default address is zero.
4156 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4157 If defined, the number of bits used to address bytes in a
4158 single page in the EEPROM device. A 64 byte page, for example
4159 would require six bits.
4161 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4162 If defined, the number of milliseconds to delay between
4163 page writes. The default is zero milliseconds.
4165 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4166 The length in bytes of the EEPROM memory array address. Note
4167 that this is NOT the chip address length!
4169 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4170 EEPROM chips that implement "address overflow" are ones
4171 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4172 address and the extra bits end up in the "chip address" bit
4173 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4176 Note that we consider the length of the address field to
4177 still be one byte because the extra address bits are hidden
4178 in the chip address.
4180 - CONFIG_SYS_EEPROM_SIZE:
4181 The size in bytes of the EEPROM device.
4183 - CONFIG_ENV_EEPROM_IS_ON_I2C
4184 define this, if you have I2C and SPI activated, and your
4185 EEPROM, which holds the environment, is on the I2C bus.
4187 - CONFIG_I2C_ENV_EEPROM_BUS
4188 if you have an Environment on an EEPROM reached over
4189 I2C muxes, you can define here, how to reach this
4190 EEPROM. For example:
4192 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4194 EEPROM which holds the environment, is reached over
4195 a pca9547 i2c mux with address 0x70, channel 3.
4197 - CONFIG_ENV_IS_IN_DATAFLASH:
4199 Define this if you have a DataFlash memory device which you
4200 want to use for the environment.
4202 - CONFIG_ENV_OFFSET:
4206 These three #defines specify the offset and size of the
4207 environment area within the total memory of your DataFlash placed
4208 at the specified address.
4210 - CONFIG_ENV_IS_IN_SPI_FLASH:
4212 Define this if you have a SPI Flash memory device which you
4213 want to use for the environment.
4215 - CONFIG_ENV_OFFSET:
4218 These two #defines specify the offset and size of the
4219 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4220 aligned to an erase sector boundary.
4222 - CONFIG_ENV_SECT_SIZE:
4224 Define the SPI flash's sector size.
4226 - CONFIG_ENV_OFFSET_REDUND (optional):
4228 This setting describes a second storage area of CONFIG_ENV_SIZE
4229 size used to hold a redundant copy of the environment data, so
4230 that there is a valid backup copy in case there is a power failure
4231 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4232 aligned to an erase sector boundary.
4234 - CONFIG_ENV_SPI_BUS (optional):
4235 - CONFIG_ENV_SPI_CS (optional):
4237 Define the SPI bus and chip select. If not defined they will be 0.
4239 - CONFIG_ENV_SPI_MAX_HZ (optional):
4241 Define the SPI max work clock. If not defined then use 1MHz.
4243 - CONFIG_ENV_SPI_MODE (optional):
4245 Define the SPI work mode. If not defined then use SPI_MODE_3.
4247 - CONFIG_ENV_IS_IN_REMOTE:
4249 Define this if you have a remote memory space which you
4250 want to use for the local device's environment.
4255 These two #defines specify the address and size of the
4256 environment area within the remote memory space. The
4257 local device can get the environment from remote memory
4258 space by SRIO or PCIE links.
4260 BE CAREFUL! For some special cases, the local device can not use
4261 "saveenv" command. For example, the local device will get the
4262 environment stored in a remote NOR flash by SRIO or PCIE link,
4263 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4265 - CONFIG_ENV_IS_IN_NAND:
4267 Define this if you have a NAND device which you want to use
4268 for the environment.
4270 - CONFIG_ENV_OFFSET:
4273 These two #defines specify the offset and size of the environment
4274 area within the first NAND device. CONFIG_ENV_OFFSET must be
4275 aligned to an erase block boundary.
4277 - CONFIG_ENV_OFFSET_REDUND (optional):
4279 This setting describes a second storage area of CONFIG_ENV_SIZE
4280 size used to hold a redundant copy of the environment data, so
4281 that there is a valid backup copy in case there is a power failure
4282 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4283 aligned to an erase block boundary.
4285 - CONFIG_ENV_RANGE (optional):
4287 Specifies the length of the region in which the environment
4288 can be written. This should be a multiple of the NAND device's
4289 block size. Specifying a range with more erase blocks than
4290 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4291 the range to be avoided.
4293 - CONFIG_ENV_OFFSET_OOB (optional):
4295 Enables support for dynamically retrieving the offset of the
4296 environment from block zero's out-of-band data. The
4297 "nand env.oob" command can be used to record this offset.
4298 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4299 using CONFIG_ENV_OFFSET_OOB.
4301 - CONFIG_NAND_ENV_DST
4303 Defines address in RAM to which the nand_spl code should copy the
4304 environment. If redundant environment is used, it will be copied to
4305 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4307 - CONFIG_ENV_IS_IN_UBI:
4309 Define this if you have an UBI volume that you want to use for the
4310 environment. This has the benefit of wear-leveling the environment
4311 accesses, which is important on NAND.
4313 - CONFIG_ENV_UBI_PART:
4315 Define this to a string that is the mtd partition containing the UBI.
4317 - CONFIG_ENV_UBI_VOLUME:
4319 Define this to the name of the volume that you want to store the
4322 - CONFIG_ENV_UBI_VOLUME_REDUND:
4324 Define this to the name of another volume to store a second copy of
4325 the environment in. This will enable redundant environments in UBI.
4326 It is assumed that both volumes are in the same MTD partition.
4328 - CONFIG_UBI_SILENCE_MSG
4329 - CONFIG_UBIFS_SILENCE_MSG
4331 You will probably want to define these to avoid a really noisy system
4332 when storing the env in UBI.
4334 - CONFIG_ENV_IS_IN_FAT:
4335 Define this if you want to use the FAT file system for the environment.
4337 - FAT_ENV_INTERFACE:
4339 Define this to a string that is the name of the block device.
4341 - FAT_ENV_DEV_AND_PART:
4343 Define this to a string to specify the partition of the device. It can
4346 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4347 - "D:P": device D partition P. Error occurs if device D has no
4350 - "D" or "D:": device D partition 1 if device D has partition
4351 table, or the whole device D if has no partition
4353 - "D:auto": first partition in device D with bootable flag set.
4354 If none, first valid paratition in device D. If no
4355 partition table then means device D.
4359 It's a string of the FAT file name. This file use to store the
4363 This should be defined. Otherwise it cannot save the envrionment file.
4365 - CONFIG_ENV_IS_IN_MMC:
4367 Define this if you have an MMC device which you want to use for the
4370 - CONFIG_SYS_MMC_ENV_DEV:
4372 Specifies which MMC device the environment is stored in.
4374 - CONFIG_SYS_MMC_ENV_PART (optional):
4376 Specifies which MMC partition the environment is stored in. If not
4377 set, defaults to partition 0, the user area. Common values might be
4378 1 (first MMC boot partition), 2 (second MMC boot partition).
4380 - CONFIG_ENV_OFFSET:
4383 These two #defines specify the offset and size of the environment
4384 area within the specified MMC device.
4386 If offset is positive (the usual case), it is treated as relative to
4387 the start of the MMC partition. If offset is negative, it is treated
4388 as relative to the end of the MMC partition. This can be useful if
4389 your board may be fitted with different MMC devices, which have
4390 different sizes for the MMC partitions, and you always want the
4391 environment placed at the very end of the partition, to leave the
4392 maximum possible space before it, to store other data.
4394 These two values are in units of bytes, but must be aligned to an
4395 MMC sector boundary.
4397 - CONFIG_ENV_OFFSET_REDUND (optional):
4399 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4400 hold a redundant copy of the environment data. This provides a
4401 valid backup copy in case the other copy is corrupted, e.g. due
4402 to a power failure during a "saveenv" operation.
4404 This value may also be positive or negative; this is handled in the
4405 same way as CONFIG_ENV_OFFSET.
4407 This value is also in units of bytes, but must also be aligned to
4408 an MMC sector boundary.
4410 - CONFIG_ENV_SIZE_REDUND (optional):
4412 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4413 set. If this value is set, it must be set to the same value as
4416 - CONFIG_SYS_SPI_INIT_OFFSET
4418 Defines offset to the initial SPI buffer area in DPRAM. The
4419 area is used at an early stage (ROM part) if the environment
4420 is configured to reside in the SPI EEPROM: We need a 520 byte
4421 scratch DPRAM area. It is used between the two initialization
4422 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4423 to be a good choice since it makes it far enough from the
4424 start of the data area as well as from the stack pointer.
4426 Please note that the environment is read-only until the monitor
4427 has been relocated to RAM and a RAM copy of the environment has been
4428 created; also, when using EEPROM you will have to use getenv_f()
4429 until then to read environment variables.
4431 The environment is protected by a CRC32 checksum. Before the monitor
4432 is relocated into RAM, as a result of a bad CRC you will be working
4433 with the compiled-in default environment - *silently*!!! [This is
4434 necessary, because the first environment variable we need is the
4435 "baudrate" setting for the console - if we have a bad CRC, we don't
4436 have any device yet where we could complain.]
4438 Note: once the monitor has been relocated, then it will complain if
4439 the default environment is used; a new CRC is computed as soon as you
4440 use the "saveenv" command to store a valid environment.
4442 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4443 Echo the inverted Ethernet link state to the fault LED.
4445 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4446 also needs to be defined.
4448 - CONFIG_SYS_FAULT_MII_ADDR:
4449 MII address of the PHY to check for the Ethernet link state.
4451 - CONFIG_NS16550_MIN_FUNCTIONS:
4452 Define this if you desire to only have use of the NS16550_init
4453 and NS16550_putc functions for the serial driver located at
4454 drivers/serial/ns16550.c. This option is useful for saving
4455 space for already greatly restricted images, including but not
4456 limited to NAND_SPL configurations.
4458 - CONFIG_DISPLAY_BOARDINFO
4459 Display information about the board that U-Boot is running on
4460 when U-Boot starts up. The board function checkboard() is called
4463 - CONFIG_DISPLAY_BOARDINFO_LATE
4464 Similar to the previous option, but display this information
4465 later, once stdio is running and output goes to the LCD, if
4468 - CONFIG_BOARD_SIZE_LIMIT:
4469 Maximum size of the U-Boot image. When defined, the
4470 build system checks that the actual size does not
4473 Low Level (hardware related) configuration options:
4474 ---------------------------------------------------
4476 - CONFIG_SYS_CACHELINE_SIZE:
4477 Cache Line Size of the CPU.
4479 - CONFIG_SYS_DEFAULT_IMMR:
4480 Default address of the IMMR after system reset.
4482 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4483 and RPXsuper) to be able to adjust the position of
4484 the IMMR register after a reset.
4486 - CONFIG_SYS_CCSRBAR_DEFAULT:
4487 Default (power-on reset) physical address of CCSR on Freescale
4490 - CONFIG_SYS_CCSRBAR:
4491 Virtual address of CCSR. On a 32-bit build, this is typically
4492 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4494 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4495 for cross-platform code that uses that macro instead.
4497 - CONFIG_SYS_CCSRBAR_PHYS:
4498 Physical address of CCSR. CCSR can be relocated to a new
4499 physical address, if desired. In this case, this macro should
4500 be set to that address. Otherwise, it should be set to the
4501 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4502 is typically relocated on 36-bit builds. It is recommended
4503 that this macro be defined via the _HIGH and _LOW macros:
4505 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4506 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4508 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4509 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4510 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4511 used in assembly code, so it must not contain typecasts or
4512 integer size suffixes (e.g. "ULL").
4514 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4515 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4516 used in assembly code, so it must not contain typecasts or
4517 integer size suffixes (e.g. "ULL").
4519 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4520 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4521 forced to a value that ensures that CCSR is not relocated.
4523 - Floppy Disk Support:
4524 CONFIG_SYS_FDC_DRIVE_NUMBER
4526 the default drive number (default value 0)
4528 CONFIG_SYS_ISA_IO_STRIDE
4530 defines the spacing between FDC chipset registers
4533 CONFIG_SYS_ISA_IO_OFFSET
4535 defines the offset of register from address. It
4536 depends on which part of the data bus is connected to
4537 the FDC chipset. (default value 0)
4539 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4540 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4543 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4544 fdc_hw_init() is called at the beginning of the FDC
4545 setup. fdc_hw_init() must be provided by the board
4546 source code. It is used to make hardware dependant
4550 Most IDE controllers were designed to be connected with PCI
4551 interface. Only few of them were designed for AHB interface.
4552 When software is doing ATA command and data transfer to
4553 IDE devices through IDE-AHB controller, some additional
4554 registers accessing to these kind of IDE-AHB controller
4557 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4558 DO NOT CHANGE unless you know exactly what you're
4559 doing! (11-4) [MPC8xx/82xx systems only]
4561 - CONFIG_SYS_INIT_RAM_ADDR:
4563 Start address of memory area that can be used for
4564 initial data and stack; please note that this must be
4565 writable memory that is working WITHOUT special
4566 initialization, i. e. you CANNOT use normal RAM which
4567 will become available only after programming the
4568 memory controller and running certain initialization
4571 U-Boot uses the following memory types:
4572 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4573 - MPC824X: data cache
4574 - PPC4xx: data cache
4576 - CONFIG_SYS_GBL_DATA_OFFSET:
4578 Offset of the initial data structure in the memory
4579 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4580 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4581 data is located at the end of the available space
4582 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4583 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4584 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4585 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4588 On the MPC824X (or other systems that use the data
4589 cache for initial memory) the address chosen for
4590 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4591 point to an otherwise UNUSED address space between
4592 the top of RAM and the start of the PCI space.
4594 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4596 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4598 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4600 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4602 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4604 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4606 - CONFIG_SYS_OR_TIMING_SDRAM:
4609 - CONFIG_SYS_MAMR_PTA:
4610 periodic timer for refresh
4612 - CONFIG_SYS_DER: Debug Event Register (37-47)
4614 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4615 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4616 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4617 CONFIG_SYS_BR1_PRELIM:
4618 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4620 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4621 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4622 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4623 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4625 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4626 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4627 Machine Mode Register and Memory Periodic Timer
4628 Prescaler definitions (SDRAM timing)
4630 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4631 enable I2C microcode relocation patch (MPC8xx);
4632 define relocation offset in DPRAM [DSP2]
4634 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4635 enable SMC microcode relocation patch (MPC8xx);
4636 define relocation offset in DPRAM [SMC1]
4638 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4639 enable SPI microcode relocation patch (MPC8xx);
4640 define relocation offset in DPRAM [SCC4]
4642 - CONFIG_SYS_USE_OSCCLK:
4643 Use OSCM clock mode on MBX8xx board. Be careful,
4644 wrong setting might damage your board. Read
4645 doc/README.MBX before setting this variable!
4647 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4648 Offset of the bootmode word in DPRAM used by post
4649 (Power On Self Tests). This definition overrides
4650 #define'd default value in commproc.h resp.
4653 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4654 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4655 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4656 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4657 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4658 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4659 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4660 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4661 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4663 - CONFIG_PCI_DISABLE_PCIE:
4664 Disable PCI-Express on systems where it is supported but not
4667 - CONFIG_PCI_ENUM_ONLY
4668 Only scan through and get the devices on the busses.
4669 Don't do any setup work, presumably because someone or
4670 something has already done it, and we don't need to do it
4671 a second time. Useful for platforms that are pre-booted
4672 by coreboot or similar.
4674 - CONFIG_PCI_INDIRECT_BRIDGE:
4675 Enable support for indirect PCI bridges.
4678 Chip has SRIO or not
4681 Board has SRIO 1 port available
4684 Board has SRIO 2 port available
4686 - CONFIG_SRIO_PCIE_BOOT_MASTER
4687 Board can support master function for Boot from SRIO and PCIE
4689 - CONFIG_SYS_SRIOn_MEM_VIRT:
4690 Virtual Address of SRIO port 'n' memory region
4692 - CONFIG_SYS_SRIOn_MEM_PHYS:
4693 Physical Address of SRIO port 'n' memory region
4695 - CONFIG_SYS_SRIOn_MEM_SIZE:
4696 Size of SRIO port 'n' memory region
4698 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4699 Defined to tell the NAND controller that the NAND chip is using
4701 Not all NAND drivers use this symbol.
4702 Example of drivers that use it:
4703 - drivers/mtd/nand/ndfc.c
4704 - drivers/mtd/nand/mxc_nand.c
4706 - CONFIG_SYS_NDFC_EBC0_CFG
4707 Sets the EBC0_CFG register for the NDFC. If not defined
4708 a default value will be used.
4711 Get DDR timing information from an I2C EEPROM. Common
4712 with pluggable memory modules such as SODIMMs
4715 I2C address of the SPD EEPROM
4717 - CONFIG_SYS_SPD_BUS_NUM
4718 If SPD EEPROM is on an I2C bus other than the first
4719 one, specify here. Note that the value must resolve
4720 to something your driver can deal with.
4722 - CONFIG_SYS_DDR_RAW_TIMING
4723 Get DDR timing information from other than SPD. Common with
4724 soldered DDR chips onboard without SPD. DDR raw timing
4725 parameters are extracted from datasheet and hard-coded into
4726 header files or board specific files.
4728 - CONFIG_FSL_DDR_INTERACTIVE
4729 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4731 - CONFIG_SYS_83XX_DDR_USES_CS0
4732 Only for 83xx systems. If specified, then DDR should
4733 be configured using CS0 and CS1 instead of CS2 and CS3.
4735 - CONFIG_ETHER_ON_FEC[12]
4736 Define to enable FEC[12] on a 8xx series processor.
4738 - CONFIG_FEC[12]_PHY
4739 Define to the hardcoded PHY address which corresponds
4740 to the given FEC; i. e.
4741 #define CONFIG_FEC1_PHY 4
4742 means that the PHY with address 4 is connected to FEC1
4744 When set to -1, means to probe for first available.
4746 - CONFIG_FEC[12]_PHY_NORXERR
4747 The PHY does not have a RXERR line (RMII only).
4748 (so program the FEC to ignore it).
4751 Enable RMII mode for all FECs.
4752 Note that this is a global option, we can't
4753 have one FEC in standard MII mode and another in RMII mode.
4755 - CONFIG_CRC32_VERIFY
4756 Add a verify option to the crc32 command.
4759 => crc32 -v <address> <count> <crc32>
4761 Where address/count indicate a memory area
4762 and crc32 is the correct crc32 which the
4766 Add the "loopw" memory command. This only takes effect if
4767 the memory commands are activated globally (CONFIG_CMD_MEM).
4770 Add the "mdc" and "mwc" memory commands. These are cyclic
4775 This command will print 4 bytes (10,11,12,13) each 500 ms.
4777 => mwc.l 100 12345678 10
4778 This command will write 12345678 to address 100 all 10 ms.
4780 This only takes effect if the memory commands are activated
4781 globally (CONFIG_CMD_MEM).
4783 - CONFIG_SKIP_LOWLEVEL_INIT
4784 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4785 low level initializations (like setting up the memory
4786 controller) are omitted and/or U-Boot does not
4787 relocate itself into RAM.
4789 Normally this variable MUST NOT be defined. The only
4790 exception is when U-Boot is loaded (to RAM) by some
4791 other boot loader or by a debugger which performs
4792 these initializations itself.
4795 Modifies the behaviour of start.S when compiling a loader
4796 that is executed before the actual U-Boot. E.g. when
4797 compiling a NAND SPL.
4800 Modifies the behaviour of start.S when compiling a loader
4801 that is executed after the SPL and before the actual U-Boot.
4802 It is loaded by the SPL.
4804 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4805 Only for 85xx systems. If this variable is specified, the section
4806 .resetvec is not kept and the section .bootpg is placed in the
4807 previous 4k of the .text section.
4809 - CONFIG_ARCH_MAP_SYSMEM
4810 Generally U-Boot (and in particular the md command) uses
4811 effective address. It is therefore not necessary to regard
4812 U-Boot address as virtual addresses that need to be translated
4813 to physical addresses. However, sandbox requires this, since
4814 it maintains its own little RAM buffer which contains all
4815 addressable memory. This option causes some memory accesses
4816 to be mapped through map_sysmem() / unmap_sysmem().
4818 - CONFIG_USE_ARCH_MEMCPY
4819 CONFIG_USE_ARCH_MEMSET
4820 If these options are used a optimized version of memcpy/memset will
4821 be used if available. These functions may be faster under some
4822 conditions but may increase the binary size.
4824 - CONFIG_X86_RESET_VECTOR
4825 If defined, the x86 reset vector code is included. This is not
4826 needed when U-Boot is running from Coreboot.
4829 Defines the MPU clock speed (in MHz).
4831 NOTE : currently only supported on AM335x platforms.
4833 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4834 Enables the RTC32K OSC on AM33xx based plattforms
4836 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
4837 Option to disable subpage write in NAND driver
4838 driver that uses this:
4839 drivers/mtd/nand/davinci_nand.c
4841 Freescale QE/FMAN Firmware Support:
4842 -----------------------------------
4844 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4845 loading of "firmware", which is encoded in the QE firmware binary format.
4846 This firmware often needs to be loaded during U-Boot booting, so macros
4847 are used to identify the storage device (NOR flash, SPI, etc) and the address
4850 - CONFIG_SYS_FMAN_FW_ADDR
4851 The address in the storage device where the FMAN microcode is located. The
4852 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4855 - CONFIG_SYS_QE_FW_ADDR
4856 The address in the storage device where the QE microcode is located. The
4857 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4860 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4861 The maximum possible size of the firmware. The firmware binary format
4862 has a field that specifies the actual size of the firmware, but it
4863 might not be possible to read any part of the firmware unless some
4864 local storage is allocated to hold the entire firmware first.
4866 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4867 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4868 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4869 virtual address in NOR flash.
4871 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4872 Specifies that QE/FMAN firmware is located in NAND flash.
4873 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4875 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4876 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4877 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4879 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4880 Specifies that QE/FMAN firmware is located on the primary SPI
4881 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4883 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4884 Specifies that QE/FMAN firmware is located in the remote (master)
4885 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4886 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4887 window->master inbound window->master LAW->the ucode address in
4888 master's memory space.
4890 Freescale Layerscape Management Complex Firmware Support:
4891 ---------------------------------------------------------
4892 The Freescale Layerscape Management Complex (MC) supports the loading of
4894 This firmware often needs to be loaded during U-Boot booting, so macros
4895 are used to identify the storage device (NOR flash, SPI, etc) and the address
4898 - CONFIG_FSL_MC_ENET
4899 Enable the MC driver for Layerscape SoCs.
4901 - CONFIG_SYS_LS_MC_FW_ADDR
4902 The address in the storage device where the firmware is located. The
4903 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
4906 - CONFIG_SYS_LS_MC_FW_LENGTH
4907 The maximum possible size of the firmware. The firmware binary format
4908 has a field that specifies the actual size of the firmware, but it
4909 might not be possible to read any part of the firmware unless some
4910 local storage is allocated to hold the entire firmware first.
4912 - CONFIG_SYS_LS_MC_FW_IN_NOR
4913 Specifies that MC firmware is located in NOR flash, mapped as
4914 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
4915 virtual address in NOR flash.
4917 Building the Software:
4918 ======================
4920 Building U-Boot has been tested in several native build environments
4921 and in many different cross environments. Of course we cannot support
4922 all possibly existing versions of cross development tools in all
4923 (potentially obsolete) versions. In case of tool chain problems we
4924 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4925 which is extensively used to build and test U-Boot.
4927 If you are not using a native environment, it is assumed that you
4928 have GNU cross compiling tools available in your path. In this case,
4929 you must set the environment variable CROSS_COMPILE in your shell.
4930 Note that no changes to the Makefile or any other source files are
4931 necessary. For example using the ELDK on a 4xx CPU, please enter:
4933 $ CROSS_COMPILE=ppc_4xx-
4934 $ export CROSS_COMPILE
4936 Note: If you wish to generate Windows versions of the utilities in
4937 the tools directory you can use the MinGW toolchain
4938 (http://www.mingw.org). Set your HOST tools to the MinGW
4939 toolchain and execute 'make tools'. For example:
4941 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4943 Binaries such as tools/mkimage.exe will be created which can
4944 be executed on computers running Windows.
4946 U-Boot is intended to be simple to build. After installing the
4947 sources you must configure U-Boot for one specific board type. This
4952 where "NAME_defconfig" is the name of one of the existing configu-
4953 rations; see boards.cfg for supported names.
4955 Note: for some board special configuration names may exist; check if
4956 additional information is available from the board vendor; for
4957 instance, the TQM823L systems are available without (standard)
4958 or with LCD support. You can select such additional "features"
4959 when choosing the configuration, i. e.
4961 make TQM823L_defconfig
4962 - will configure for a plain TQM823L, i. e. no LCD support
4964 make TQM823L_LCD_defconfig
4965 - will configure for a TQM823L with U-Boot console on LCD
4970 Finally, type "make all", and you should get some working U-Boot
4971 images ready for download to / installation on your system:
4973 - "u-boot.bin" is a raw binary image
4974 - "u-boot" is an image in ELF binary format
4975 - "u-boot.srec" is in Motorola S-Record format
4977 By default the build is performed locally and the objects are saved
4978 in the source directory. One of the two methods can be used to change
4979 this behavior and build U-Boot to some external directory:
4981 1. Add O= to the make command line invocations:
4983 make O=/tmp/build distclean
4984 make O=/tmp/build NAME_defconfig
4985 make O=/tmp/build all
4987 2. Set environment variable BUILD_DIR to point to the desired location:
4989 export BUILD_DIR=/tmp/build
4994 Note that the command line "O=" setting overrides the BUILD_DIR environment
4998 Please be aware that the Makefiles assume you are using GNU make, so
4999 for instance on NetBSD you might need to use "gmake" instead of
5003 If the system board that you have is not listed, then you will need
5004 to port U-Boot to your hardware platform. To do this, follow these
5007 1. Add a new configuration option for your board to the toplevel
5008 "boards.cfg" file, using the existing entries as examples.
5009 Follow the instructions there to keep the boards in order.
5010 2. Create a new directory to hold your board specific code. Add any
5011 files you need. In your board directory, you will need at least
5012 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
5013 3. Create a new configuration file "include/configs/<board>.h" for
5015 3. If you're porting U-Boot to a new CPU, then also create a new
5016 directory to hold your CPU specific code. Add any files you need.
5017 4. Run "make <board>_defconfig" with your new name.
5018 5. Type "make", and you should get a working "u-boot.srec" file
5019 to be installed on your target system.
5020 6. Debug and solve any problems that might arise.
5021 [Of course, this last step is much harder than it sounds.]
5024 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5025 ==============================================================
5027 If you have modified U-Boot sources (for instance added a new board
5028 or support for new devices, a new CPU, etc.) you are expected to
5029 provide feedback to the other developers. The feedback normally takes
5030 the form of a "patch", i. e. a context diff against a certain (latest
5031 official or latest in the git repository) version of U-Boot sources.
5033 But before you submit such a patch, please verify that your modifi-
5034 cation did not break existing code. At least make sure that *ALL* of
5035 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5036 just run the "MAKEALL" script, which will configure and build U-Boot
5037 for ALL supported system. Be warned, this will take a while. You can
5038 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5039 environment variable to the script, i. e. to use the ELDK cross tools
5042 CROSS_COMPILE=ppc_8xx- MAKEALL
5044 or to build on a native PowerPC system you can type
5046 CROSS_COMPILE=' ' MAKEALL
5048 When using the MAKEALL script, the default behaviour is to build
5049 U-Boot in the source directory. This location can be changed by
5050 setting the BUILD_DIR environment variable. Also, for each target
5051 built, the MAKEALL script saves two log files (<target>.ERR and
5052 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5053 location can be changed by setting the MAKEALL_LOGDIR environment
5054 variable. For example:
5056 export BUILD_DIR=/tmp/build
5057 export MAKEALL_LOGDIR=/tmp/log
5058 CROSS_COMPILE=ppc_8xx- MAKEALL
5060 With the above settings build objects are saved in the /tmp/build,
5061 log files are saved in the /tmp/log and the source tree remains clean
5062 during the whole build process.
5065 See also "U-Boot Porting Guide" below.
5068 Monitor Commands - Overview:
5069 ============================
5071 go - start application at address 'addr'
5072 run - run commands in an environment variable
5073 bootm - boot application image from memory
5074 bootp - boot image via network using BootP/TFTP protocol
5075 bootz - boot zImage from memory
5076 tftpboot- boot image via network using TFTP protocol
5077 and env variables "ipaddr" and "serverip"
5078 (and eventually "gatewayip")
5079 tftpput - upload a file via network using TFTP protocol
5080 rarpboot- boot image via network using RARP/TFTP protocol
5081 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5082 loads - load S-Record file over serial line
5083 loadb - load binary file over serial line (kermit mode)
5085 mm - memory modify (auto-incrementing)
5086 nm - memory modify (constant address)
5087 mw - memory write (fill)
5089 cmp - memory compare
5090 crc32 - checksum calculation
5091 i2c - I2C sub-system
5092 sspi - SPI utility commands
5093 base - print or set address offset
5094 printenv- print environment variables
5095 setenv - set environment variables
5096 saveenv - save environment variables to persistent storage
5097 protect - enable or disable FLASH write protection
5098 erase - erase FLASH memory
5099 flinfo - print FLASH memory information
5100 nand - NAND memory operations (see doc/README.nand)
5101 bdinfo - print Board Info structure
5102 iminfo - print header information for application image
5103 coninfo - print console devices and informations
5104 ide - IDE sub-system
5105 loop - infinite loop on address range
5106 loopw - infinite write loop on address range
5107 mtest - simple RAM test
5108 icache - enable or disable instruction cache
5109 dcache - enable or disable data cache
5110 reset - Perform RESET of the CPU
5111 echo - echo args to console
5112 version - print monitor version
5113 help - print online help
5114 ? - alias for 'help'
5117 Monitor Commands - Detailed Description:
5118 ========================================
5122 For now: just type "help <command>".
5125 Environment Variables:
5126 ======================
5128 U-Boot supports user configuration using Environment Variables which
5129 can be made persistent by saving to Flash memory.
5131 Environment Variables are set using "setenv", printed using
5132 "printenv", and saved to Flash using "saveenv". Using "setenv"
5133 without a value can be used to delete a variable from the
5134 environment. As long as you don't save the environment you are
5135 working with an in-memory copy. In case the Flash area containing the
5136 environment is erased by accident, a default environment is provided.
5138 Some configuration options can be set using Environment Variables.
5140 List of environment variables (most likely not complete):
5142 baudrate - see CONFIG_BAUDRATE
5144 bootdelay - see CONFIG_BOOTDELAY
5146 bootcmd - see CONFIG_BOOTCOMMAND
5148 bootargs - Boot arguments when booting an RTOS image
5150 bootfile - Name of the image to load with TFTP
5152 bootm_low - Memory range available for image processing in the bootm
5153 command can be restricted. This variable is given as
5154 a hexadecimal number and defines lowest address allowed
5155 for use by the bootm command. See also "bootm_size"
5156 environment variable. Address defined by "bootm_low" is
5157 also the base of the initial memory mapping for the Linux
5158 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5161 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5162 This variable is given as a hexadecimal number and it
5163 defines the size of the memory region starting at base
5164 address bootm_low that is accessible by the Linux kernel
5165 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5166 as the default value if it is defined, and bootm_size is
5169 bootm_size - Memory range available for image processing in the bootm
5170 command can be restricted. This variable is given as
5171 a hexadecimal number and defines the size of the region
5172 allowed for use by the bootm command. See also "bootm_low"
5173 environment variable.
5175 updatefile - Location of the software update file on a TFTP server, used
5176 by the automatic software update feature. Please refer to
5177 documentation in doc/README.update for more details.
5179 autoload - if set to "no" (any string beginning with 'n'),
5180 "bootp" will just load perform a lookup of the
5181 configuration from the BOOTP server, but not try to
5182 load any image using TFTP
5184 autostart - if set to "yes", an image loaded using the "bootp",
5185 "rarpboot", "tftpboot" or "diskboot" commands will
5186 be automatically started (by internally calling
5189 If set to "no", a standalone image passed to the
5190 "bootm" command will be copied to the load address
5191 (and eventually uncompressed), but NOT be started.
5192 This can be used to load and uncompress arbitrary
5195 fdt_high - if set this restricts the maximum address that the
5196 flattened device tree will be copied into upon boot.
5197 For example, if you have a system with 1 GB memory
5198 at physical address 0x10000000, while Linux kernel
5199 only recognizes the first 704 MB as low memory, you
5200 may need to set fdt_high as 0x3C000000 to have the
5201 device tree blob be copied to the maximum address
5202 of the 704 MB low memory, so that Linux kernel can
5203 access it during the boot procedure.
5205 If this is set to the special value 0xFFFFFFFF then
5206 the fdt will not be copied at all on boot. For this
5207 to work it must reside in writable memory, have
5208 sufficient padding on the end of it for u-boot to
5209 add the information it needs into it, and the memory
5210 must be accessible by the kernel.
5212 fdtcontroladdr- if set this is the address of the control flattened
5213 device tree used by U-Boot when CONFIG_OF_CONTROL is
5216 i2cfast - (PPC405GP|PPC405EP only)
5217 if set to 'y' configures Linux I2C driver for fast
5218 mode (400kHZ). This environment variable is used in
5219 initialization code. So, for changes to be effective
5220 it must be saved and board must be reset.
5222 initrd_high - restrict positioning of initrd images:
5223 If this variable is not set, initrd images will be
5224 copied to the highest possible address in RAM; this
5225 is usually what you want since it allows for
5226 maximum initrd size. If for some reason you want to
5227 make sure that the initrd image is loaded below the
5228 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5229 variable to a value of "no" or "off" or "0".
5230 Alternatively, you can set it to a maximum upper
5231 address to use (U-Boot will still check that it
5232 does not overwrite the U-Boot stack and data).
5234 For instance, when you have a system with 16 MB
5235 RAM, and want to reserve 4 MB from use by Linux,
5236 you can do this by adding "mem=12M" to the value of
5237 the "bootargs" variable. However, now you must make
5238 sure that the initrd image is placed in the first
5239 12 MB as well - this can be done with
5241 setenv initrd_high 00c00000
5243 If you set initrd_high to 0xFFFFFFFF, this is an
5244 indication to U-Boot that all addresses are legal
5245 for the Linux kernel, including addresses in flash
5246 memory. In this case U-Boot will NOT COPY the
5247 ramdisk at all. This may be useful to reduce the
5248 boot time on your system, but requires that this
5249 feature is supported by your Linux kernel.
5251 ipaddr - IP address; needed for tftpboot command
5253 loadaddr - Default load address for commands like "bootp",
5254 "rarpboot", "tftpboot", "loadb" or "diskboot"
5256 loads_echo - see CONFIG_LOADS_ECHO
5258 serverip - TFTP server IP address; needed for tftpboot command
5260 bootretry - see CONFIG_BOOT_RETRY_TIME
5262 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5264 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5266 ethprime - controls which interface is used first.
5268 ethact - controls which interface is currently active.
5269 For example you can do the following
5271 => setenv ethact FEC
5272 => ping 192.168.0.1 # traffic sent on FEC
5273 => setenv ethact SCC
5274 => ping 10.0.0.1 # traffic sent on SCC
5276 ethrotate - When set to "no" U-Boot does not go through all
5277 available network interfaces.
5278 It just stays at the currently selected interface.
5280 netretry - When set to "no" each network operation will
5281 either succeed or fail without retrying.
5282 When set to "once" the network operation will
5283 fail when all the available network interfaces
5284 are tried once without success.
5285 Useful on scripts which control the retry operation
5288 npe_ucode - set load address for the NPE microcode
5290 silent_linux - If set then linux will be told to boot silently, by
5291 changing the console to be empty. If "yes" it will be
5292 made silent. If "no" it will not be made silent. If
5293 unset, then it will be made silent if the U-Boot console
5296 tftpsrcport - If this is set, the value is used for TFTP's
5299 tftpdstport - If this is set, the value is used for TFTP's UDP
5300 destination port instead of the Well Know Port 69.
5302 tftpblocksize - Block size to use for TFTP transfers; if not set,
5303 we use the TFTP server's default block size
5305 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5306 seconds, minimum value is 1000 = 1 second). Defines
5307 when a packet is considered to be lost so it has to
5308 be retransmitted. The default is 5000 = 5 seconds.
5309 Lowering this value may make downloads succeed
5310 faster in networks with high packet loss rates or
5311 with unreliable TFTP servers.
5313 vlan - When set to a value < 4095 the traffic over
5314 Ethernet is encapsulated/received over 802.1q
5317 The following image location variables contain the location of images
5318 used in booting. The "Image" column gives the role of the image and is
5319 not an environment variable name. The other columns are environment
5320 variable names. "File Name" gives the name of the file on a TFTP
5321 server, "RAM Address" gives the location in RAM the image will be
5322 loaded to, and "Flash Location" gives the image's address in NOR
5323 flash or offset in NAND flash.
5325 *Note* - these variables don't have to be defined for all boards, some
5326 boards currenlty use other variables for these purposes, and some
5327 boards use these variables for other purposes.
5329 Image File Name RAM Address Flash Location
5330 ----- --------- ----------- --------------
5331 u-boot u-boot u-boot_addr_r u-boot_addr
5332 Linux kernel bootfile kernel_addr_r kernel_addr
5333 device tree blob fdtfile fdt_addr_r fdt_addr
5334 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5336 The following environment variables may be used and automatically
5337 updated by the network boot commands ("bootp" and "rarpboot"),
5338 depending the information provided by your boot server:
5340 bootfile - see above
5341 dnsip - IP address of your Domain Name Server
5342 dnsip2 - IP address of your secondary Domain Name Server
5343 gatewayip - IP address of the Gateway (Router) to use
5344 hostname - Target hostname
5346 netmask - Subnet Mask
5347 rootpath - Pathname of the root filesystem on the NFS server
5348 serverip - see above
5351 There are two special Environment Variables:
5353 serial# - contains hardware identification information such
5354 as type string and/or serial number
5355 ethaddr - Ethernet address
5357 These variables can be set only once (usually during manufacturing of
5358 the board). U-Boot refuses to delete or overwrite these variables
5359 once they have been set once.
5362 Further special Environment Variables:
5364 ver - Contains the U-Boot version string as printed
5365 with the "version" command. This variable is
5366 readonly (see CONFIG_VERSION_VARIABLE).
5369 Please note that changes to some configuration parameters may take
5370 only effect after the next boot (yes, that's just like Windoze :-).
5373 Callback functions for environment variables:
5374 ---------------------------------------------
5376 For some environment variables, the behavior of u-boot needs to change
5377 when their values are changed. This functionailty allows functions to
5378 be associated with arbitrary variables. On creation, overwrite, or
5379 deletion, the callback will provide the opportunity for some side
5380 effect to happen or for the change to be rejected.
5382 The callbacks are named and associated with a function using the
5383 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5385 These callbacks are associated with variables in one of two ways. The
5386 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5387 in the board configuration to a string that defines a list of
5388 associations. The list must be in the following format:
5390 entry = variable_name[:callback_name]
5393 If the callback name is not specified, then the callback is deleted.
5394 Spaces are also allowed anywhere in the list.
5396 Callbacks can also be associated by defining the ".callbacks" variable
5397 with the same list format above. Any association in ".callbacks" will
5398 override any association in the static list. You can define
5399 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5400 ".callbacks" envirnoment variable in the default or embedded environment.
5403 Command Line Parsing:
5404 =====================
5406 There are two different command line parsers available with U-Boot:
5407 the old "simple" one, and the much more powerful "hush" shell:
5409 Old, simple command line parser:
5410 --------------------------------
5412 - supports environment variables (through setenv / saveenv commands)
5413 - several commands on one line, separated by ';'
5414 - variable substitution using "... ${name} ..." syntax
5415 - special characters ('$', ';') can be escaped by prefixing with '\',
5417 setenv bootcmd bootm \${address}
5418 - You can also escape text by enclosing in single apostrophes, for example:
5419 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5424 - similar to Bourne shell, with control structures like
5425 if...then...else...fi, for...do...done; while...do...done,
5426 until...do...done, ...
5427 - supports environment ("global") variables (through setenv / saveenv
5428 commands) and local shell variables (through standard shell syntax
5429 "name=value"); only environment variables can be used with "run"
5435 (1) If a command line (or an environment variable executed by a "run"
5436 command) contains several commands separated by semicolon, and
5437 one of these commands fails, then the remaining commands will be
5440 (2) If you execute several variables with one call to run (i. e.
5441 calling run with a list of variables as arguments), any failing
5442 command will cause "run" to terminate, i. e. the remaining
5443 variables are not executed.
5445 Note for Redundant Ethernet Interfaces:
5446 =======================================
5448 Some boards come with redundant Ethernet interfaces; U-Boot supports
5449 such configurations and is capable of automatic selection of a
5450 "working" interface when needed. MAC assignment works as follows:
5452 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5453 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5454 "eth1addr" (=>eth1), "eth2addr", ...
5456 If the network interface stores some valid MAC address (for instance
5457 in SROM), this is used as default address if there is NO correspon-
5458 ding setting in the environment; if the corresponding environment
5459 variable is set, this overrides the settings in the card; that means:
5461 o If the SROM has a valid MAC address, and there is no address in the
5462 environment, the SROM's address is used.
5464 o If there is no valid address in the SROM, and a definition in the
5465 environment exists, then the value from the environment variable is
5468 o If both the SROM and the environment contain a MAC address, and
5469 both addresses are the same, this MAC address is used.
5471 o If both the SROM and the environment contain a MAC address, and the
5472 addresses differ, the value from the environment is used and a
5475 o If neither SROM nor the environment contain a MAC address, an error
5478 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5479 will be programmed into hardware as part of the initialization process. This
5480 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5481 The naming convention is as follows:
5482 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5487 U-Boot is capable of booting (and performing other auxiliary operations on)
5488 images in two formats:
5490 New uImage format (FIT)
5491 -----------------------
5493 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5494 to Flattened Device Tree). It allows the use of images with multiple
5495 components (several kernels, ramdisks, etc.), with contents protected by
5496 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5502 Old image format is based on binary files which can be basically anything,
5503 preceded by a special header; see the definitions in include/image.h for
5504 details; basically, the header defines the following image properties:
5506 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5507 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5508 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5509 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5511 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5512 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5513 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5514 * Compression Type (uncompressed, gzip, bzip2)
5520 The header is marked by a special Magic Number, and both the header
5521 and the data portions of the image are secured against corruption by
5528 Although U-Boot should support any OS or standalone application
5529 easily, the main focus has always been on Linux during the design of
5532 U-Boot includes many features that so far have been part of some
5533 special "boot loader" code within the Linux kernel. Also, any
5534 "initrd" images to be used are no longer part of one big Linux image;
5535 instead, kernel and "initrd" are separate images. This implementation
5536 serves several purposes:
5538 - the same features can be used for other OS or standalone
5539 applications (for instance: using compressed images to reduce the
5540 Flash memory footprint)
5542 - it becomes much easier to port new Linux kernel versions because
5543 lots of low-level, hardware dependent stuff are done by U-Boot
5545 - the same Linux kernel image can now be used with different "initrd"
5546 images; of course this also means that different kernel images can
5547 be run with the same "initrd". This makes testing easier (you don't
5548 have to build a new "zImage.initrd" Linux image when you just
5549 change a file in your "initrd"). Also, a field-upgrade of the
5550 software is easier now.
5556 Porting Linux to U-Boot based systems:
5557 ---------------------------------------
5559 U-Boot cannot save you from doing all the necessary modifications to
5560 configure the Linux device drivers for use with your target hardware
5561 (no, we don't intend to provide a full virtual machine interface to
5564 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5566 Just make sure your machine specific header file (for instance
5567 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5568 Information structure as we define in include/asm-<arch>/u-boot.h,
5569 and make sure that your definition of IMAP_ADDR uses the same value
5570 as your U-Boot configuration in CONFIG_SYS_IMMR.
5572 Note that U-Boot now has a driver model, a unified model for drivers.
5573 If you are adding a new driver, plumb it into driver model. If there
5574 is no uclass available, you are encouraged to create one. See
5578 Configuring the Linux kernel:
5579 -----------------------------
5581 No specific requirements for U-Boot. Make sure you have some root
5582 device (initial ramdisk, NFS) for your target system.
5585 Building a Linux Image:
5586 -----------------------
5588 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5589 not used. If you use recent kernel source, a new build target
5590 "uImage" will exist which automatically builds an image usable by
5591 U-Boot. Most older kernels also have support for a "pImage" target,
5592 which was introduced for our predecessor project PPCBoot and uses a
5593 100% compatible format.
5597 make TQM850L_defconfig
5602 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5603 encapsulate a compressed Linux kernel image with header information,
5604 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5606 * build a standard "vmlinux" kernel image (in ELF binary format):
5608 * convert the kernel into a raw binary image:
5610 ${CROSS_COMPILE}-objcopy -O binary \
5611 -R .note -R .comment \
5612 -S vmlinux linux.bin
5614 * compress the binary image:
5618 * package compressed binary image for U-Boot:
5620 mkimage -A ppc -O linux -T kernel -C gzip \
5621 -a 0 -e 0 -n "Linux Kernel Image" \
5622 -d linux.bin.gz uImage
5625 The "mkimage" tool can also be used to create ramdisk images for use
5626 with U-Boot, either separated from the Linux kernel image, or
5627 combined into one file. "mkimage" encapsulates the images with a 64
5628 byte header containing information about target architecture,
5629 operating system, image type, compression method, entry points, time
5630 stamp, CRC32 checksums, etc.
5632 "mkimage" can be called in two ways: to verify existing images and
5633 print the header information, or to build new images.
5635 In the first form (with "-l" option) mkimage lists the information
5636 contained in the header of an existing U-Boot image; this includes
5637 checksum verification:
5639 tools/mkimage -l image
5640 -l ==> list image header information
5642 The second form (with "-d" option) is used to build a U-Boot image
5643 from a "data file" which is used as image payload:
5645 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5646 -n name -d data_file image
5647 -A ==> set architecture to 'arch'
5648 -O ==> set operating system to 'os'
5649 -T ==> set image type to 'type'
5650 -C ==> set compression type 'comp'
5651 -a ==> set load address to 'addr' (hex)
5652 -e ==> set entry point to 'ep' (hex)
5653 -n ==> set image name to 'name'
5654 -d ==> use image data from 'datafile'
5656 Right now, all Linux kernels for PowerPC systems use the same load
5657 address (0x00000000), but the entry point address depends on the
5660 - 2.2.x kernels have the entry point at 0x0000000C,
5661 - 2.3.x and later kernels have the entry point at 0x00000000.
5663 So a typical call to build a U-Boot image would read:
5665 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5666 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5667 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5668 > examples/uImage.TQM850L
5669 Image Name: 2.4.4 kernel for TQM850L
5670 Created: Wed Jul 19 02:34:59 2000
5671 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5672 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5673 Load Address: 0x00000000
5674 Entry Point: 0x00000000
5676 To verify the contents of the image (or check for corruption):
5678 -> tools/mkimage -l examples/uImage.TQM850L
5679 Image Name: 2.4.4 kernel for TQM850L
5680 Created: Wed Jul 19 02:34:59 2000
5681 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5682 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5683 Load Address: 0x00000000
5684 Entry Point: 0x00000000
5686 NOTE: for embedded systems where boot time is critical you can trade
5687 speed for memory and install an UNCOMPRESSED image instead: this
5688 needs more space in Flash, but boots much faster since it does not
5689 need to be uncompressed:
5691 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5692 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5693 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5694 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5695 > examples/uImage.TQM850L-uncompressed
5696 Image Name: 2.4.4 kernel for TQM850L
5697 Created: Wed Jul 19 02:34:59 2000
5698 Image Type: PowerPC Linux Kernel Image (uncompressed)
5699 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5700 Load Address: 0x00000000
5701 Entry Point: 0x00000000
5704 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5705 when your kernel is intended to use an initial ramdisk:
5707 -> tools/mkimage -n 'Simple Ramdisk Image' \
5708 > -A ppc -O linux -T ramdisk -C gzip \
5709 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5710 Image Name: Simple Ramdisk Image
5711 Created: Wed Jan 12 14:01:50 2000
5712 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5713 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5714 Load Address: 0x00000000
5715 Entry Point: 0x00000000
5717 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5718 option performs the converse operation of the mkimage's second form (the "-d"
5719 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5722 tools/dumpimage -i image -p position data_file
5723 -i ==> extract from the 'image' a specific 'data_file', \
5724 indexed by 'position'
5727 Installing a Linux Image:
5728 -------------------------
5730 To downloading a U-Boot image over the serial (console) interface,
5731 you must convert the image to S-Record format:
5733 objcopy -I binary -O srec examples/image examples/image.srec
5735 The 'objcopy' does not understand the information in the U-Boot
5736 image header, so the resulting S-Record file will be relative to
5737 address 0x00000000. To load it to a given address, you need to
5738 specify the target address as 'offset' parameter with the 'loads'
5741 Example: install the image to address 0x40100000 (which on the
5742 TQM8xxL is in the first Flash bank):
5744 => erase 40100000 401FFFFF
5750 ## Ready for S-Record download ...
5751 ~>examples/image.srec
5752 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5754 15989 15990 15991 15992
5755 [file transfer complete]
5757 ## Start Addr = 0x00000000
5760 You can check the success of the download using the 'iminfo' command;
5761 this includes a checksum verification so you can be sure no data
5762 corruption happened:
5766 ## Checking Image at 40100000 ...
5767 Image Name: 2.2.13 for initrd on TQM850L
5768 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5769 Data Size: 335725 Bytes = 327 kB = 0 MB
5770 Load Address: 00000000
5771 Entry Point: 0000000c
5772 Verifying Checksum ... OK
5778 The "bootm" command is used to boot an application that is stored in
5779 memory (RAM or Flash). In case of a Linux kernel image, the contents
5780 of the "bootargs" environment variable is passed to the kernel as
5781 parameters. You can check and modify this variable using the
5782 "printenv" and "setenv" commands:
5785 => printenv bootargs
5786 bootargs=root=/dev/ram
5788 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5790 => printenv bootargs
5791 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5794 ## Booting Linux kernel at 40020000 ...
5795 Image Name: 2.2.13 for NFS on TQM850L
5796 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5797 Data Size: 381681 Bytes = 372 kB = 0 MB
5798 Load Address: 00000000
5799 Entry Point: 0000000c
5800 Verifying Checksum ... OK
5801 Uncompressing Kernel Image ... OK
5802 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
5803 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5804 time_init: decrementer frequency = 187500000/60
5805 Calibrating delay loop... 49.77 BogoMIPS
5806 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5809 If you want to boot a Linux kernel with initial RAM disk, you pass
5810 the memory addresses of both the kernel and the initrd image (PPBCOOT
5811 format!) to the "bootm" command:
5813 => imi 40100000 40200000
5815 ## Checking Image at 40100000 ...
5816 Image Name: 2.2.13 for initrd on TQM850L
5817 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5818 Data Size: 335725 Bytes = 327 kB = 0 MB
5819 Load Address: 00000000
5820 Entry Point: 0000000c
5821 Verifying Checksum ... OK
5823 ## Checking Image at 40200000 ...
5824 Image Name: Simple Ramdisk Image
5825 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5826 Data Size: 566530 Bytes = 553 kB = 0 MB
5827 Load Address: 00000000
5828 Entry Point: 00000000
5829 Verifying Checksum ... OK
5831 => bootm 40100000 40200000
5832 ## Booting Linux kernel at 40100000 ...
5833 Image Name: 2.2.13 for initrd on TQM850L
5834 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5835 Data Size: 335725 Bytes = 327 kB = 0 MB
5836 Load Address: 00000000
5837 Entry Point: 0000000c
5838 Verifying Checksum ... OK
5839 Uncompressing Kernel Image ... OK
5840 ## Loading RAMDisk Image at 40200000 ...
5841 Image Name: Simple Ramdisk Image
5842 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5843 Data Size: 566530 Bytes = 553 kB = 0 MB
5844 Load Address: 00000000
5845 Entry Point: 00000000
5846 Verifying Checksum ... OK
5847 Loading Ramdisk ... OK
5848 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
5849 Boot arguments: root=/dev/ram
5850 time_init: decrementer frequency = 187500000/60
5851 Calibrating delay loop... 49.77 BogoMIPS
5853 RAMDISK: Compressed image found at block 0
5854 VFS: Mounted root (ext2 filesystem).
5858 Boot Linux and pass a flat device tree:
5861 First, U-Boot must be compiled with the appropriate defines. See the section
5862 titled "Linux Kernel Interface" above for a more in depth explanation. The
5863 following is an example of how to start a kernel and pass an updated
5869 oft=oftrees/mpc8540ads.dtb
5870 => tftp $oftaddr $oft
5871 Speed: 1000, full duplex
5873 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5874 Filename 'oftrees/mpc8540ads.dtb'.
5875 Load address: 0x300000
5878 Bytes transferred = 4106 (100a hex)
5879 => tftp $loadaddr $bootfile
5880 Speed: 1000, full duplex
5882 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5884 Load address: 0x200000
5885 Loading:############
5887 Bytes transferred = 1029407 (fb51f hex)
5892 => bootm $loadaddr - $oftaddr
5893 ## Booting image at 00200000 ...
5894 Image Name: Linux-2.6.17-dirty
5895 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5896 Data Size: 1029343 Bytes = 1005.2 kB
5897 Load Address: 00000000
5898 Entry Point: 00000000
5899 Verifying Checksum ... OK
5900 Uncompressing Kernel Image ... OK
5901 Booting using flat device tree at 0x300000
5902 Using MPC85xx ADS machine description
5903 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5907 More About U-Boot Image Types:
5908 ------------------------------
5910 U-Boot supports the following image types:
5912 "Standalone Programs" are directly runnable in the environment
5913 provided by U-Boot; it is expected that (if they behave
5914 well) you can continue to work in U-Boot after return from
5915 the Standalone Program.
5916 "OS Kernel Images" are usually images of some Embedded OS which
5917 will take over control completely. Usually these programs
5918 will install their own set of exception handlers, device
5919 drivers, set up the MMU, etc. - this means, that you cannot
5920 expect to re-enter U-Boot except by resetting the CPU.
5921 "RAMDisk Images" are more or less just data blocks, and their
5922 parameters (address, size) are passed to an OS kernel that is
5924 "Multi-File Images" contain several images, typically an OS
5925 (Linux) kernel image and one or more data images like
5926 RAMDisks. This construct is useful for instance when you want
5927 to boot over the network using BOOTP etc., where the boot
5928 server provides just a single image file, but you want to get
5929 for instance an OS kernel and a RAMDisk image.
5931 "Multi-File Images" start with a list of image sizes, each
5932 image size (in bytes) specified by an "uint32_t" in network
5933 byte order. This list is terminated by an "(uint32_t)0".
5934 Immediately after the terminating 0 follow the images, one by
5935 one, all aligned on "uint32_t" boundaries (size rounded up to
5936 a multiple of 4 bytes).
5938 "Firmware Images" are binary images containing firmware (like
5939 U-Boot or FPGA images) which usually will be programmed to
5942 "Script files" are command sequences that will be executed by
5943 U-Boot's command interpreter; this feature is especially
5944 useful when you configure U-Boot to use a real shell (hush)
5945 as command interpreter.
5947 Booting the Linux zImage:
5948 -------------------------
5950 On some platforms, it's possible to boot Linux zImage. This is done
5951 using the "bootz" command. The syntax of "bootz" command is the same
5952 as the syntax of "bootm" command.
5954 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5955 kernel with raw initrd images. The syntax is slightly different, the
5956 address of the initrd must be augmented by it's size, in the following
5957 format: "<initrd addres>:<initrd size>".
5963 One of the features of U-Boot is that you can dynamically load and
5964 run "standalone" applications, which can use some resources of
5965 U-Boot like console I/O functions or interrupt services.
5967 Two simple examples are included with the sources:
5972 'examples/hello_world.c' contains a small "Hello World" Demo
5973 application; it is automatically compiled when you build U-Boot.
5974 It's configured to run at address 0x00040004, so you can play with it
5978 ## Ready for S-Record download ...
5979 ~>examples/hello_world.srec
5980 1 2 3 4 5 6 7 8 9 10 11 ...
5981 [file transfer complete]
5983 ## Start Addr = 0x00040004
5985 => go 40004 Hello World! This is a test.
5986 ## Starting application at 0x00040004 ...
5997 Hit any key to exit ...
5999 ## Application terminated, rc = 0x0
6001 Another example, which demonstrates how to register a CPM interrupt
6002 handler with the U-Boot code, can be found in 'examples/timer.c'.
6003 Here, a CPM timer is set up to generate an interrupt every second.
6004 The interrupt service routine is trivial, just printing a '.'
6005 character, but this is just a demo program. The application can be
6006 controlled by the following keys:
6008 ? - print current values og the CPM Timer registers
6009 b - enable interrupts and start timer
6010 e - stop timer and disable interrupts
6011 q - quit application
6014 ## Ready for S-Record download ...
6015 ~>examples/timer.srec
6016 1 2 3 4 5 6 7 8 9 10 11 ...
6017 [file transfer complete]
6019 ## Start Addr = 0x00040004
6022 ## Starting application at 0x00040004 ...
6025 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6028 [q, b, e, ?] Set interval 1000000 us
6031 [q, b, e, ?] ........
6032 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6035 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6038 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6041 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6043 [q, b, e, ?] ...Stopping timer
6045 [q, b, e, ?] ## Application terminated, rc = 0x0
6051 Over time, many people have reported problems when trying to use the
6052 "minicom" terminal emulation program for serial download. I (wd)
6053 consider minicom to be broken, and recommend not to use it. Under
6054 Unix, I recommend to use C-Kermit for general purpose use (and
6055 especially for kermit binary protocol download ("loadb" command), and
6056 use "cu" for S-Record download ("loads" command). See
6057 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6058 for help with kermit.
6061 Nevertheless, if you absolutely want to use it try adding this
6062 configuration to your "File transfer protocols" section:
6064 Name Program Name U/D FullScr IO-Red. Multi
6065 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6066 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6072 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6073 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6075 Building requires a cross environment; it is known to work on
6076 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6077 need gmake since the Makefiles are not compatible with BSD make).
6078 Note that the cross-powerpc package does not install include files;
6079 attempting to build U-Boot will fail because <machine/ansi.h> is
6080 missing. This file has to be installed and patched manually:
6082 # cd /usr/pkg/cross/powerpc-netbsd/include
6084 # ln -s powerpc machine
6085 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6086 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6088 Native builds *don't* work due to incompatibilities between native
6089 and U-Boot include files.
6091 Booting assumes that (the first part of) the image booted is a
6092 stage-2 loader which in turn loads and then invokes the kernel
6093 proper. Loader sources will eventually appear in the NetBSD source
6094 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6095 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6098 Implementation Internals:
6099 =========================
6101 The following is not intended to be a complete description of every
6102 implementation detail. However, it should help to understand the
6103 inner workings of U-Boot and make it easier to port it to custom
6107 Initial Stack, Global Data:
6108 ---------------------------
6110 The implementation of U-Boot is complicated by the fact that U-Boot
6111 starts running out of ROM (flash memory), usually without access to
6112 system RAM (because the memory controller is not initialized yet).
6113 This means that we don't have writable Data or BSS segments, and BSS
6114 is not initialized as zero. To be able to get a C environment working
6115 at all, we have to allocate at least a minimal stack. Implementation
6116 options for this are defined and restricted by the CPU used: Some CPU
6117 models provide on-chip memory (like the IMMR area on MPC8xx and
6118 MPC826x processors), on others (parts of) the data cache can be
6119 locked as (mis-) used as memory, etc.
6121 Chris Hallinan posted a good summary of these issues to the
6122 U-Boot mailing list:
6124 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6126 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6129 Correct me if I'm wrong, folks, but the way I understand it
6130 is this: Using DCACHE as initial RAM for Stack, etc, does not
6131 require any physical RAM backing up the cache. The cleverness
6132 is that the cache is being used as a temporary supply of
6133 necessary storage before the SDRAM controller is setup. It's
6134 beyond the scope of this list to explain the details, but you
6135 can see how this works by studying the cache architecture and
6136 operation in the architecture and processor-specific manuals.
6138 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6139 is another option for the system designer to use as an
6140 initial stack/RAM area prior to SDRAM being available. Either
6141 option should work for you. Using CS 4 should be fine if your
6142 board designers haven't used it for something that would
6143 cause you grief during the initial boot! It is frequently not
6146 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6147 with your processor/board/system design. The default value
6148 you will find in any recent u-boot distribution in
6149 walnut.h should work for you. I'd set it to a value larger
6150 than your SDRAM module. If you have a 64MB SDRAM module, set
6151 it above 400_0000. Just make sure your board has no resources
6152 that are supposed to respond to that address! That code in
6153 start.S has been around a while and should work as is when
6154 you get the config right.
6159 It is essential to remember this, since it has some impact on the C
6160 code for the initialization procedures:
6162 * Initialized global data (data segment) is read-only. Do not attempt
6165 * Do not use any uninitialized global data (or implicitely initialized
6166 as zero data - BSS segment) at all - this is undefined, initiali-
6167 zation is performed later (when relocating to RAM).
6169 * Stack space is very limited. Avoid big data buffers or things like
6172 Having only the stack as writable memory limits means we cannot use
6173 normal global data to share information beween the code. But it
6174 turned out that the implementation of U-Boot can be greatly
6175 simplified by making a global data structure (gd_t) available to all
6176 functions. We could pass a pointer to this data as argument to _all_
6177 functions, but this would bloat the code. Instead we use a feature of
6178 the GCC compiler (Global Register Variables) to share the data: we
6179 place a pointer (gd) to the global data into a register which we
6180 reserve for this purpose.
6182 When choosing a register for such a purpose we are restricted by the
6183 relevant (E)ABI specifications for the current architecture, and by
6184 GCC's implementation.
6186 For PowerPC, the following registers have specific use:
6188 R2: reserved for system use
6189 R3-R4: parameter passing and return values
6190 R5-R10: parameter passing
6191 R13: small data area pointer
6195 (U-Boot also uses R12 as internal GOT pointer. r12
6196 is a volatile register so r12 needs to be reset when
6197 going back and forth between asm and C)
6199 ==> U-Boot will use R2 to hold a pointer to the global data
6201 Note: on PPC, we could use a static initializer (since the
6202 address of the global data structure is known at compile time),
6203 but it turned out that reserving a register results in somewhat
6204 smaller code - although the code savings are not that big (on
6205 average for all boards 752 bytes for the whole U-Boot image,
6206 624 text + 127 data).
6208 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6209 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6211 ==> U-Boot will use P3 to hold a pointer to the global data
6213 On ARM, the following registers are used:
6215 R0: function argument word/integer result
6216 R1-R3: function argument word
6217 R9: platform specific
6218 R10: stack limit (used only if stack checking is enabled)
6219 R11: argument (frame) pointer
6220 R12: temporary workspace
6223 R15: program counter
6225 ==> U-Boot will use R9 to hold a pointer to the global data
6227 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6229 On Nios II, the ABI is documented here:
6230 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6232 ==> U-Boot will use gp to hold a pointer to the global data
6234 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6235 to access small data sections, so gp is free.
6237 On NDS32, the following registers are used:
6239 R0-R1: argument/return
6241 R15: temporary register for assembler
6242 R16: trampoline register
6243 R28: frame pointer (FP)
6244 R29: global pointer (GP)
6245 R30: link register (LP)
6246 R31: stack pointer (SP)
6247 PC: program counter (PC)
6249 ==> U-Boot will use R10 to hold a pointer to the global data
6251 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6252 or current versions of GCC may "optimize" the code too much.
6257 U-Boot runs in system state and uses physical addresses, i.e. the
6258 MMU is not used either for address mapping nor for memory protection.
6260 The available memory is mapped to fixed addresses using the memory
6261 controller. In this process, a contiguous block is formed for each
6262 memory type (Flash, SDRAM, SRAM), even when it consists of several
6263 physical memory banks.
6265 U-Boot is installed in the first 128 kB of the first Flash bank (on
6266 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6267 booting and sizing and initializing DRAM, the code relocates itself
6268 to the upper end of DRAM. Immediately below the U-Boot code some
6269 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6270 configuration setting]. Below that, a structure with global Board
6271 Info data is placed, followed by the stack (growing downward).
6273 Additionally, some exception handler code is copied to the low 8 kB
6274 of DRAM (0x00000000 ... 0x00001FFF).
6276 So a typical memory configuration with 16 MB of DRAM could look like
6279 0x0000 0000 Exception Vector code
6282 0x0000 2000 Free for Application Use
6288 0x00FB FF20 Monitor Stack (Growing downward)
6289 0x00FB FFAC Board Info Data and permanent copy of global data
6290 0x00FC 0000 Malloc Arena
6293 0x00FE 0000 RAM Copy of Monitor Code
6294 ... eventually: LCD or video framebuffer
6295 ... eventually: pRAM (Protected RAM - unchanged by reset)
6296 0x00FF FFFF [End of RAM]
6299 System Initialization:
6300 ----------------------
6302 In the reset configuration, U-Boot starts at the reset entry point
6303 (on most PowerPC systems at address 0x00000100). Because of the reset
6304 configuration for CS0# this is a mirror of the onboard Flash memory.
6305 To be able to re-map memory U-Boot then jumps to its link address.
6306 To be able to implement the initialization code in C, a (small!)
6307 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6308 which provide such a feature like MPC8xx or MPC8260), or in a locked
6309 part of the data cache. After that, U-Boot initializes the CPU core,
6310 the caches and the SIU.
6312 Next, all (potentially) available memory banks are mapped using a
6313 preliminary mapping. For example, we put them on 512 MB boundaries
6314 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6315 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6316 programmed for SDRAM access. Using the temporary configuration, a
6317 simple memory test is run that determines the size of the SDRAM
6320 When there is more than one SDRAM bank, and the banks are of
6321 different size, the largest is mapped first. For equal size, the first
6322 bank (CS2#) is mapped first. The first mapping is always for address
6323 0x00000000, with any additional banks following immediately to create
6324 contiguous memory starting from 0.
6326 Then, the monitor installs itself at the upper end of the SDRAM area
6327 and allocates memory for use by malloc() and for the global Board
6328 Info data; also, the exception vector code is copied to the low RAM
6329 pages, and the final stack is set up.
6331 Only after this relocation will you have a "normal" C environment;
6332 until that you are restricted in several ways, mostly because you are
6333 running from ROM, and because the code will have to be relocated to a
6337 U-Boot Porting Guide:
6338 ----------------------
6340 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6344 int main(int argc, char *argv[])
6346 sighandler_t no_more_time;
6348 signal(SIGALRM, no_more_time);
6349 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6351 if (available_money > available_manpower) {
6352 Pay consultant to port U-Boot;
6356 Download latest U-Boot source;
6358 Subscribe to u-boot mailing list;
6361 email("Hi, I am new to U-Boot, how do I get started?");
6364 Read the README file in the top level directory;
6365 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6366 Read applicable doc/*.README;
6367 Read the source, Luke;
6368 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6371 if (available_money > toLocalCurrency ($2500))
6374 Add a lot of aggravation and time;
6376 if (a similar board exists) { /* hopefully... */
6377 cp -a board/<similar> board/<myboard>
6378 cp include/configs/<similar>.h include/configs/<myboard>.h
6380 Create your own board support subdirectory;
6381 Create your own board include/configs/<myboard>.h file;
6383 Edit new board/<myboard> files
6384 Edit new include/configs/<myboard>.h
6389 Add / modify source code;
6393 email("Hi, I am having problems...");
6395 Send patch file to the U-Boot email list;
6396 if (reasonable critiques)
6397 Incorporate improvements from email list code review;
6399 Defend code as written;
6405 void no_more_time (int sig)
6414 All contributions to U-Boot should conform to the Linux kernel
6415 coding style; see the file "Documentation/CodingStyle" and the script
6416 "scripts/Lindent" in your Linux kernel source directory.
6418 Source files originating from a different project (for example the
6419 MTD subsystem) are generally exempt from these guidelines and are not
6420 reformated to ease subsequent migration to newer versions of those
6423 Please note that U-Boot is implemented in C (and to some small parts in
6424 Assembler); no C++ is used, so please do not use C++ style comments (//)
6427 Please also stick to the following formatting rules:
6428 - remove any trailing white space
6429 - use TAB characters for indentation and vertical alignment, not spaces
6430 - make sure NOT to use DOS '\r\n' line feeds
6431 - do not add more than 2 consecutive empty lines to source files
6432 - do not add trailing empty lines to source files
6434 Submissions which do not conform to the standards may be returned
6435 with a request to reformat the changes.
6441 Since the number of patches for U-Boot is growing, we need to
6442 establish some rules. Submissions which do not conform to these rules
6443 may be rejected, even when they contain important and valuable stuff.
6445 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6448 see http://lists.denx.de/mailman/listinfo/u-boot
6450 When you send a patch, please include the following information with
6453 * For bug fixes: a description of the bug and how your patch fixes
6454 this bug. Please try to include a way of demonstrating that the
6455 patch actually fixes something.
6457 * For new features: a description of the feature and your
6460 * A CHANGELOG entry as plaintext (separate from the patch)
6462 * For major contributions, your entry to the CREDITS file
6464 * When you add support for a new board, don't forget to add a
6465 maintainer e-mail address to the boards.cfg file, too.
6467 * If your patch adds new configuration options, don't forget to
6468 document these in the README file.
6470 * The patch itself. If you are using git (which is *strongly*
6471 recommended) you can easily generate the patch using the
6472 "git format-patch". If you then use "git send-email" to send it to
6473 the U-Boot mailing list, you will avoid most of the common problems
6474 with some other mail clients.
6476 If you cannot use git, use "diff -purN OLD NEW". If your version of
6477 diff does not support these options, then get the latest version of
6480 The current directory when running this command shall be the parent
6481 directory of the U-Boot source tree (i. e. please make sure that
6482 your patch includes sufficient directory information for the
6485 We prefer patches as plain text. MIME attachments are discouraged,
6486 and compressed attachments must not be used.
6488 * If one logical set of modifications affects or creates several
6489 files, all these changes shall be submitted in a SINGLE patch file.
6491 * Changesets that contain different, unrelated modifications shall be
6492 submitted as SEPARATE patches, one patch per changeset.
6497 * Before sending the patch, run the MAKEALL script on your patched
6498 source tree and make sure that no errors or warnings are reported
6499 for any of the boards.
6501 * Keep your modifications to the necessary minimum: A patch
6502 containing several unrelated changes or arbitrary reformats will be
6503 returned with a request to re-formatting / split it.
6505 * If you modify existing code, make sure that your new code does not
6506 add to the memory footprint of the code ;-) Small is beautiful!
6507 When adding new features, these should compile conditionally only
6508 (using #ifdef), and the resulting code with the new feature
6509 disabled must not need more memory than the old code without your
6512 * Remember that there is a size limit of 100 kB per message on the
6513 u-boot mailing list. Bigger patches will be moderated. If they are
6514 reasonable and not too big, they will be acknowledged. But patches
6515 bigger than the size limit should be avoided.
projects / u-boot.git / blob