2 # (C) Copyright 2000 - 2012
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
57 Note: There is no CHANGELOG file in the actual U-Boot source tree;
58 it can be created dynamically from the Git log using:
66 In case you have questions about, problems with or contributions for
67 U-Boot you should send a message to the U-Boot mailing list at
69 on the mailing list - please search the archive before asking FAQ's.
70 Please see http://lists.denx.de/pipermail/u-boot and
71 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
74 Where to get source code:
75 =========================
77 The U-Boot source code is maintained in the git repository at
78 git://www.denx.de/git/u-boot.git ; you can browse it online at
79 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
81 The "snapshot" links on this page allow you to download tarballs of
82 any version you might be interested in. Official releases are also
83 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
86 Pre-built (and tested) images are available from
87 ftp://ftp.denx.de/pub/u-boot/images/
93 - start from 8xxrom sources
94 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
96 - make it easier to add custom boards
97 - make it possible to add other [PowerPC] CPUs
98 - extend functions, especially:
99 * Provide extended interface to Linux boot loader
102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
103 - create ARMBoot project (http://sourceforge.net/projects/armboot)
104 - add other CPU families (starting with ARM)
105 - create U-Boot project (http://sourceforge.net/projects/u-boot)
106 - current project page: see http://www.denx.de/wiki/U-Boot
112 The "official" name of this project is "Das U-Boot". The spelling
113 "U-Boot" shall be used in all written text (documentation, comments
114 in source files etc.). Example:
116 This is the README file for the U-Boot project.
118 File names etc. shall be based on the string "u-boot". Examples:
120 include/asm-ppc/u-boot.h
122 #include <asm/u-boot.h>
124 Variable names, preprocessor constants etc. shall be either based on
125 the string "u_boot" or on "U_BOOT". Example:
127 U_BOOT_VERSION u_boot_logo
128 IH_OS_U_BOOT u_boot_hush_start
134 Starting with the release in October 2008, the names of the releases
135 were changed from numerical release numbers without deeper meaning
136 into a time stamp based numbering. Regular releases are identified by
137 names consisting of the calendar year and month of the release date.
138 Additional fields (if present) indicate release candidates or bug fix
139 releases in "stable" maintenance trees.
142 U-Boot v2009.11 - Release November 2009
143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
150 /arch Architecture specific files
151 /arm Files generic to ARM architecture
152 /cpu CPU specific files
153 /arm720t Files specific to ARM 720 CPUs
154 /arm920t Files specific to ARM 920 CPUs
155 /at91 Files specific to Atmel AT91RM9200 CPU
156 /imx Files specific to Freescale MC9328 i.MX CPUs
157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
158 /arm925t Files specific to ARM 925 CPUs
159 /arm926ejs Files specific to ARM 926 CPUs
160 /arm1136 Files specific to ARM 1136 CPUs
161 /ixp Files specific to Intel XScale IXP CPUs
162 /pxa Files specific to Intel XScale PXA CPUs
163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
165 /lib Architecture specific library files
166 /avr32 Files generic to AVR32 architecture
167 /cpu CPU specific files
168 /lib Architecture specific library files
169 /blackfin Files generic to Analog Devices Blackfin architecture
170 /cpu CPU specific files
171 /lib Architecture specific library files
172 /x86 Files generic to x86 architecture
173 /cpu CPU specific files
174 /lib Architecture specific library files
175 /m68k Files generic to m68k architecture
176 /cpu CPU specific files
177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
182 /lib Architecture specific library files
183 /microblaze Files generic to microblaze architecture
184 /cpu CPU specific files
185 /lib Architecture specific library files
186 /mips Files generic to MIPS architecture
187 /cpu CPU specific files
188 /mips32 Files specific to MIPS32 CPUs
189 /xburst Files specific to Ingenic XBurst CPUs
190 /lib Architecture specific library files
191 /nds32 Files generic to NDS32 architecture
192 /cpu CPU specific files
193 /n1213 Files specific to Andes Technology N1213 CPUs
194 /lib Architecture specific library files
195 /nios2 Files generic to Altera NIOS2 architecture
196 /cpu CPU specific files
197 /lib Architecture specific library files
198 /powerpc Files generic to PowerPC architecture
199 /cpu CPU specific files
200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
201 /mpc5xx Files specific to Freescale MPC5xx CPUs
202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
203 /mpc8xx Files specific to Freescale MPC8xx CPUs
204 /mpc824x Files specific to Freescale MPC824x CPUs
205 /mpc8260 Files specific to Freescale MPC8260 CPUs
206 /mpc85xx Files specific to Freescale MPC85xx CPUs
207 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
208 /lib Architecture specific library files
209 /sh Files generic to SH architecture
210 /cpu CPU specific files
211 /sh2 Files specific to sh2 CPUs
212 /sh3 Files specific to sh3 CPUs
213 /sh4 Files specific to sh4 CPUs
214 /lib Architecture specific library files
215 /sparc Files generic to SPARC architecture
216 /cpu CPU specific files
217 /leon2 Files specific to Gaisler LEON2 SPARC CPU
218 /leon3 Files specific to Gaisler LEON3 SPARC CPU
219 /lib Architecture specific library files
220 /api Machine/arch independent API for external apps
221 /board Board dependent files
222 /common Misc architecture independent functions
223 /disk Code for disk drive partition handling
224 /doc Documentation (don't expect too much)
225 /drivers Commonly used device drivers
226 /examples Example code for standalone applications, etc.
227 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
228 /include Header Files
229 /lib Files generic to all architectures
230 /libfdt Library files to support flattened device trees
231 /lzma Library files to support LZMA decompression
232 /lzo Library files to support LZO decompression
234 /post Power On Self Test
235 /rtc Real Time Clock drivers
236 /tools Tools to build S-Record or U-Boot images, etc.
238 Software Configuration:
239 =======================
241 Configuration is usually done using C preprocessor defines; the
242 rationale behind that is to avoid dead code whenever possible.
244 There are two classes of configuration variables:
246 * Configuration _OPTIONS_:
247 These are selectable by the user and have names beginning with
250 * Configuration _SETTINGS_:
251 These depend on the hardware etc. and should not be meddled with if
252 you don't know what you're doing; they have names beginning with
255 Later we will add a configuration tool - probably similar to or even
256 identical to what's used for the Linux kernel. Right now, we have to
257 do the configuration by hand, which means creating some symbolic
258 links and editing some configuration files. We use the TQM8xxL boards
262 Selection of Processor Architecture and Board Type:
263 ---------------------------------------------------
265 For all supported boards there are ready-to-use default
266 configurations available; just type "make <board_name>_config".
268 Example: For a TQM823L module type:
273 For the Cogent platform, you need to specify the CPU type as well;
274 e.g. "make cogent_mpc8xx_config". And also configure the cogent
275 directory according to the instructions in cogent/README.
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 - Board flavour: (if CONFIG_MPC8260ADS is defined)
327 CONFIG_SYS_8260ADS - original MPC8260ADS
328 CONFIG_SYS_8266ADS - MPC8266ADS
329 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
330 CONFIG_SYS_8272ADS - MPC8272ADS
332 - Marvell Family Member
333 CONFIG_SYS_MVFS - define it if you want to enable
334 multiple fs option at one time
335 for marvell soc family
337 - MPC824X Family Member (if CONFIG_MPC824X is defined)
338 Define exactly one of
339 CONFIG_MPC8240, CONFIG_MPC8245
341 - 8xx CPU Options: (if using an MPC8xx CPU)
342 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
343 get_gclk_freq() cannot work
344 e.g. if there is no 32KHz
345 reference PIT/RTC clock
346 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
349 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
350 CONFIG_SYS_8xx_CPUCLK_MIN
351 CONFIG_SYS_8xx_CPUCLK_MAX
352 CONFIG_8xx_CPUCLK_DEFAULT
353 See doc/README.MPC866
355 CONFIG_SYS_MEASURE_CPUCLK
357 Define this to measure the actual CPU clock instead
358 of relying on the correctness of the configured
359 values. Mostly useful for board bringup to make sure
360 the PLL is locked at the intended frequency. Note
361 that this requires a (stable) reference clock (32 kHz
362 RTC clock or CONFIG_SYS_8XX_XIN)
364 CONFIG_SYS_DELAYED_ICACHE
366 Define this option if you want to enable the
367 ICache only when Code runs from RAM.
372 Specifies that the core is a 64-bit PowerPC implementation (implements
373 the "64" category of the Power ISA). This is necessary for ePAPR
374 compliance, among other possible reasons.
376 CONFIG_SYS_FSL_TBCLK_DIV
378 Defines the core time base clock divider ratio compared to the
379 system clock. On most PQ3 devices this is 8, on newer QorIQ
380 devices it can be 16 or 32. The ratio varies from SoC to Soc.
382 CONFIG_SYS_FSL_PCIE_COMPAT
384 Defines the string to utilize when trying to match PCIe device
385 tree nodes for the given platform.
387 CONFIG_SYS_PPC_E500_DEBUG_TLB
389 Enables a temporary TLB entry to be used during boot to work
390 around limitations in e500v1 and e500v2 external debugger
391 support. This reduces the portions of the boot code where
392 breakpoints and single stepping do not work. The value of this
393 symbol should be set to the TLB1 entry to be used for this
396 CONFIG_SYS_FSL_ERRATUM_A004510
398 Enables a workaround for erratum A004510. If set,
399 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
400 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
402 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
405 Defines one or two SoC revisions (low 8 bits of SVR)
406 for which the A004510 workaround should be applied.
408 The rest of SVR is either not relevant to the decision
409 of whether the erratum is present (e.g. p2040 versus
410 p2041) or is implied by the build target, which controls
411 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
413 See Freescale App Note 4493 for more information about
416 CONFIG_A003399_NOR_WORKAROUND
417 Enables a workaround for IFC erratum A003399. It is only
418 requred during NOR boot.
420 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
422 This is the value to write into CCSR offset 0x18600
423 according to the A004510 workaround.
425 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
426 This value denotes start offset of M2 memory
427 which is directly connected to the DSP core.
429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
430 This value denotes start offset of DSP CCSR space.
432 - Generic CPU options:
433 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
435 Defines the endianess of the CPU. Implementation of those
436 values is arch specific.
438 - Intel Monahans options:
439 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
441 Defines the Monahans run mode to oscillator
442 ratio. Valid values are 8, 16, 24, 31. The core
443 frequency is this value multiplied by 13 MHz.
445 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
447 Defines the Monahans turbo mode to oscillator
448 ratio. Valid values are 1 (default if undefined) and
449 2. The core frequency as calculated above is multiplied
453 CONFIG_SYS_INIT_SP_OFFSET
455 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
456 pointer. This is needed for the temporary stack before
459 CONFIG_SYS_MIPS_CACHE_MODE
461 Cache operation mode for the MIPS CPU.
462 See also arch/mips/include/asm/mipsregs.h.
464 CONF_CM_CACHABLE_NO_WA
467 CONF_CM_CACHABLE_NONCOHERENT
471 CONF_CM_CACHABLE_ACCELERATED
473 CONFIG_SYS_XWAY_EBU_BOOTCFG
475 Special option for Lantiq XWAY SoCs for booting from NOR flash.
476 See also arch/mips/cpu/mips32/start.S.
478 CONFIG_XWAY_SWAP_BYTES
480 Enable compilation of tools/xway-swap-bytes needed for Lantiq
481 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
482 be swapped if a flash programmer is used.
485 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
487 Select high exception vectors of the ARM core, e.g., do not
488 clear the V bit of the c1 register of CP15.
490 CONFIG_SYS_THUMB_BUILD
492 Use this flag to build U-Boot using the Thumb instruction
493 set for ARM architectures. Thumb instruction set provides
494 better code density. For ARM architectures that support
495 Thumb2 this flag will result in Thumb2 code generated by
498 CONFIG_ARM_ERRATA_716044
499 CONFIG_ARM_ERRATA_742230
500 CONFIG_ARM_ERRATA_743622
501 CONFIG_ARM_ERRATA_751472
503 If set, the workarounds for these ARM errata are applied early
504 during U-Boot startup. Note that these options force the
505 workarounds to be applied; no CPU-type/version detection
506 exists, unlike the similar options in the Linux kernel. Do not
507 set these options unless they apply!
512 The frequency of the timer returned by get_timer().
513 get_timer() must operate in milliseconds and this CONFIG
514 option must be set to 1000.
516 - Linux Kernel Interface:
519 U-Boot stores all clock information in Hz
520 internally. For binary compatibility with older Linux
521 kernels (which expect the clocks passed in the
522 bd_info data to be in MHz) the environment variable
523 "clocks_in_mhz" can be defined so that U-Boot
524 converts clock data to MHZ before passing it to the
526 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
527 "clocks_in_mhz=1" is automatically included in the
530 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
532 When transferring memsize parameter to linux, some versions
533 expect it to be in bytes, others in MB.
534 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
538 New kernel versions are expecting firmware settings to be
539 passed using flattened device trees (based on open firmware
543 * New libfdt-based support
544 * Adds the "fdt" command
545 * The bootm command automatically updates the fdt
547 OF_CPU - The proper name of the cpus node (only required for
548 MPC512X and MPC5xxx based boards).
549 OF_SOC - The proper name of the soc node (only required for
550 MPC512X and MPC5xxx based boards).
551 OF_TBCLK - The timebase frequency.
552 OF_STDOUT_PATH - The path to the console device
554 boards with QUICC Engines require OF_QE to set UCC MAC
557 CONFIG_OF_BOARD_SETUP
559 Board code has addition modification that it wants to make
560 to the flat device tree before handing it off to the kernel
564 This define fills in the correct boot CPU in the boot
565 param header, the default value is zero if undefined.
569 U-Boot can detect if an IDE device is present or not.
570 If not, and this new config option is activated, U-Boot
571 removes the ATA node from the DTS before booting Linux,
572 so the Linux IDE driver does not probe the device and
573 crash. This is needed for buggy hardware (uc101) where
574 no pull down resistor is connected to the signal IDE5V_DD7.
576 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
578 This setting is mandatory for all boards that have only one
579 machine type and must be used to specify the machine type
580 number as it appears in the ARM machine registry
581 (see http://www.arm.linux.org.uk/developer/machines/).
582 Only boards that have multiple machine types supported
583 in a single configuration file and the machine type is
584 runtime discoverable, do not have to use this setting.
586 - vxWorks boot parameters:
588 bootvx constructs a valid bootline using the following
589 environments variables: bootfile, ipaddr, serverip, hostname.
590 It loads the vxWorks image pointed bootfile.
592 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
593 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
594 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
595 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
597 CONFIG_SYS_VXWORKS_ADD_PARAMS
599 Add it at the end of the bootline. E.g "u=username pw=secret"
601 Note: If a "bootargs" environment is defined, it will overwride
602 the defaults discussed just above.
604 - Cache Configuration:
605 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
606 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
607 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
609 - Cache Configuration for ARM:
610 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
612 CONFIG_SYS_PL310_BASE - Physical base address of PL310
613 controller register space
618 Define this if you want support for Amba PrimeCell PL010 UARTs.
622 Define this if you want support for Amba PrimeCell PL011 UARTs.
626 If you have Amba PrimeCell PL011 UARTs, set this variable to
627 the clock speed of the UARTs.
631 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
632 define this to a list of base addresses for each (supported)
633 port. See e.g. include/configs/versatile.h
635 CONFIG_PL011_SERIAL_RLCR
637 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
638 have separate receive and transmit line control registers. Set
639 this variable to initialize the extra register.
641 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
643 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
644 boot loader that has already initialized the UART. Define this
645 variable to flush the UART at init time.
649 Depending on board, define exactly one serial port
650 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
651 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
652 console by defining CONFIG_8xx_CONS_NONE
654 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
655 port routines must be defined elsewhere
656 (i.e. serial_init(), serial_getc(), ...)
659 Enables console device for a color framebuffer. Needs following
660 defines (cf. smiLynxEM, i8042)
661 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
663 VIDEO_HW_RECTFILL graphic chip supports
666 VIDEO_HW_BITBLT graphic chip supports
667 bit-blit (cf. smiLynxEM)
668 VIDEO_VISIBLE_COLS visible pixel columns
670 VIDEO_VISIBLE_ROWS visible pixel rows
671 VIDEO_PIXEL_SIZE bytes per pixel
672 VIDEO_DATA_FORMAT graphic data format
673 (0-5, cf. cfb_console.c)
674 VIDEO_FB_ADRS framebuffer address
675 VIDEO_KBD_INIT_FCT keyboard int fct
676 (i.e. i8042_kbd_init())
677 VIDEO_TSTC_FCT test char fct
679 VIDEO_GETC_FCT get char fct
681 CONFIG_CONSOLE_CURSOR cursor drawing on/off
682 (requires blink timer
684 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
685 CONFIG_CONSOLE_TIME display time/date info in
687 (requires CONFIG_CMD_DATE)
688 CONFIG_VIDEO_LOGO display Linux logo in
690 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
691 linux_logo.h for logo.
692 Requires CONFIG_VIDEO_LOGO
693 CONFIG_CONSOLE_EXTRA_INFO
694 additional board info beside
697 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
698 a limited number of ANSI escape sequences (cursor control,
699 erase functions and limited graphics rendition control).
701 When CONFIG_CFB_CONSOLE is defined, video console is
702 default i/o. Serial console can be forced with
703 environment 'console=serial'.
705 When CONFIG_SILENT_CONSOLE is defined, all console
706 messages (by U-Boot and Linux!) can be silenced with
707 the "silent" environment variable. See
708 doc/README.silent for more information.
711 CONFIG_BAUDRATE - in bps
712 Select one of the baudrates listed in
713 CONFIG_SYS_BAUDRATE_TABLE, see below.
714 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
716 - Console Rx buffer length
717 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
718 the maximum receive buffer length for the SMC.
719 This option is actual only for 82xx and 8xx possible.
720 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
721 must be defined, to setup the maximum idle timeout for
724 - Pre-Console Buffer:
725 Prior to the console being initialised (i.e. serial UART
726 initialised etc) all console output is silently discarded.
727 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
728 buffer any console messages prior to the console being
729 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
730 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
731 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
732 bytes are output before the console is initialised, the
733 earlier bytes are discarded.
735 'Sane' compilers will generate smaller code if
736 CONFIG_PRE_CON_BUF_SZ is a power of 2
738 - Safe printf() functions
739 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
740 the printf() functions. These are defined in
741 include/vsprintf.h and include snprintf(), vsnprintf() and
742 so on. Code size increase is approximately 300-500 bytes.
743 If this option is not given then these functions will
744 silently discard their buffer size argument - this means
745 you are not getting any overflow checking in this case.
747 - Boot Delay: CONFIG_BOOTDELAY - in seconds
748 Delay before automatically booting the default image;
749 set to -1 to disable autoboot.
750 set to -2 to autoboot with no delay and not check for abort
751 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
753 See doc/README.autoboot for these options that
754 work with CONFIG_BOOTDELAY. None are required.
755 CONFIG_BOOT_RETRY_TIME
756 CONFIG_BOOT_RETRY_MIN
757 CONFIG_AUTOBOOT_KEYED
758 CONFIG_AUTOBOOT_PROMPT
759 CONFIG_AUTOBOOT_DELAY_STR
760 CONFIG_AUTOBOOT_STOP_STR
761 CONFIG_AUTOBOOT_DELAY_STR2
762 CONFIG_AUTOBOOT_STOP_STR2
763 CONFIG_ZERO_BOOTDELAY_CHECK
764 CONFIG_RESET_TO_RETRY
768 Only needed when CONFIG_BOOTDELAY is enabled;
769 define a command string that is automatically executed
770 when no character is read on the console interface
771 within "Boot Delay" after reset.
774 This can be used to pass arguments to the bootm
775 command. The value of CONFIG_BOOTARGS goes into the
776 environment value "bootargs".
778 CONFIG_RAMBOOT and CONFIG_NFSBOOT
779 The value of these goes into the environment as
780 "ramboot" and "nfsboot" respectively, and can be used
781 as a convenience, when switching between booting from
787 When this option is #defined, the existence of the
788 environment variable "preboot" will be checked
789 immediately before starting the CONFIG_BOOTDELAY
790 countdown and/or running the auto-boot command resp.
791 entering interactive mode.
793 This feature is especially useful when "preboot" is
794 automatically generated or modified. For an example
795 see the LWMON board specific code: here "preboot" is
796 modified when the user holds down a certain
797 combination of keys on the (special) keyboard when
800 - Serial Download Echo Mode:
802 If defined to 1, all characters received during a
803 serial download (using the "loads" command) are
804 echoed back. This might be needed by some terminal
805 emulations (like "cu"), but may as well just take
806 time on others. This setting #define's the initial
807 value of the "loads_echo" environment variable.
809 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
811 Select one of the baudrates listed in
812 CONFIG_SYS_BAUDRATE_TABLE, see below.
815 Monitor commands can be included or excluded
816 from the build by using the #include files
817 <config_cmd_all.h> and #undef'ing unwanted
818 commands, or using <config_cmd_default.h>
819 and augmenting with additional #define's
822 The default command configuration includes all commands
823 except those marked below with a "*".
825 CONFIG_CMD_ASKENV * ask for env variable
826 CONFIG_CMD_BDI bdinfo
827 CONFIG_CMD_BEDBUG * Include BedBug Debugger
828 CONFIG_CMD_BMP * BMP support
829 CONFIG_CMD_BSP * Board specific commands
830 CONFIG_CMD_BOOTD bootd
831 CONFIG_CMD_CACHE * icache, dcache
832 CONFIG_CMD_CONSOLE coninfo
833 CONFIG_CMD_CRC32 * crc32
834 CONFIG_CMD_DATE * support for RTC, date/time...
835 CONFIG_CMD_DHCP * DHCP support
836 CONFIG_CMD_DIAG * Diagnostics
837 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
838 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
839 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
840 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
841 CONFIG_CMD_DTT * Digital Therm and Thermostat
842 CONFIG_CMD_ECHO echo arguments
843 CONFIG_CMD_EDITENV edit env variable
844 CONFIG_CMD_EEPROM * EEPROM read/write support
845 CONFIG_CMD_ELF * bootelf, bootvx
846 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
847 CONFIG_CMD_ENV_FLAGS * display details about env flags
848 CONFIG_CMD_EXPORTENV * export the environment
849 CONFIG_CMD_EXT2 * ext2 command support
850 CONFIG_CMD_EXT4 * ext4 command support
851 CONFIG_CMD_SAVEENV saveenv
852 CONFIG_CMD_FDC * Floppy Disk Support
853 CONFIG_CMD_FAT * FAT command support
854 CONFIG_CMD_FDOS * Dos diskette Support
855 CONFIG_CMD_FLASH flinfo, erase, protect
856 CONFIG_CMD_FPGA FPGA device initialization support
857 CONFIG_CMD_FUSE * Device fuse support
858 CONFIG_CMD_GETTIME * Get time since boot
859 CONFIG_CMD_GO * the 'go' command (exec code)
860 CONFIG_CMD_GREPENV * search environment
861 CONFIG_CMD_HASH * calculate hash / digest
862 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
863 CONFIG_CMD_I2C * I2C serial bus support
864 CONFIG_CMD_IDE * IDE harddisk support
865 CONFIG_CMD_IMI iminfo
866 CONFIG_CMD_IMLS List all images found in NOR flash
867 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
868 CONFIG_CMD_IMMAP * IMMR dump support
869 CONFIG_CMD_IMPORTENV * import an environment
870 CONFIG_CMD_INI * import data from an ini file into the env
871 CONFIG_CMD_IRQ * irqinfo
872 CONFIG_CMD_ITEST Integer/string test of 2 values
873 CONFIG_CMD_JFFS2 * JFFS2 Support
874 CONFIG_CMD_KGDB * kgdb
875 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
876 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
878 CONFIG_CMD_LOADB loadb
879 CONFIG_CMD_LOADS loads
880 CONFIG_CMD_MD5SUM * print md5 message digest
881 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
882 CONFIG_CMD_MEMINFO * Display detailed memory information
883 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
885 CONFIG_CMD_MEMTEST * mtest
886 CONFIG_CMD_MISC Misc functions like sleep etc
887 CONFIG_CMD_MMC * MMC memory mapped support
888 CONFIG_CMD_MII * MII utility commands
889 CONFIG_CMD_MTDPARTS * MTD partition support
890 CONFIG_CMD_NAND * NAND support
891 CONFIG_CMD_NET bootp, tftpboot, rarpboot
892 CONFIG_CMD_NFS NFS support
893 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
894 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
895 CONFIG_CMD_PCI * pciinfo
896 CONFIG_CMD_PCMCIA * PCMCIA support
897 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
899 CONFIG_CMD_PORTIO * Port I/O
900 CONFIG_CMD_READ * Read raw data from partition
901 CONFIG_CMD_REGINFO * Register dump
902 CONFIG_CMD_RUN run command in env variable
903 CONFIG_CMD_SANDBOX * sb command to access sandbox features
904 CONFIG_CMD_SAVES * save S record dump
905 CONFIG_CMD_SCSI * SCSI Support
906 CONFIG_CMD_SDRAM * print SDRAM configuration information
907 (requires CONFIG_CMD_I2C)
908 CONFIG_CMD_SETGETDCR Support for DCR Register access
910 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
911 CONFIG_CMD_SHA1SUM * print sha1 memory digest
912 (requires CONFIG_CMD_MEMORY)
913 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
914 CONFIG_CMD_SOURCE "source" command Support
915 CONFIG_CMD_SPI * SPI serial bus support
916 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
917 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
918 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
919 CONFIG_CMD_TIMER * access to the system tick timer
920 CONFIG_CMD_USB * USB support
921 CONFIG_CMD_CDP * Cisco Discover Protocol support
922 CONFIG_CMD_MFSL * Microblaze FSL support
923 CONFIG_CMD_XIMG Load part of Multi Image
926 EXAMPLE: If you want all functions except of network
927 support you can write:
929 #include "config_cmd_all.h"
930 #undef CONFIG_CMD_NET
933 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
935 Note: Don't enable the "icache" and "dcache" commands
936 (configuration option CONFIG_CMD_CACHE) unless you know
937 what you (and your U-Boot users) are doing. Data
938 cache cannot be enabled on systems like the 8xx or
939 8260 (where accesses to the IMMR region must be
940 uncached), and it cannot be disabled on all other
941 systems where we (mis-) use the data cache to hold an
942 initial stack and some data.
945 XXX - this list needs to get updated!
947 - Regular expression support:
949 If this variable is defined, U-Boot is linked against
950 the SLRE (Super Light Regular Expression) library,
951 which adds regex support to some commands, as for
952 example "env grep" and "setexpr".
956 If this variable is defined, U-Boot will use a device tree
957 to configure its devices, instead of relying on statically
958 compiled #defines in the board file. This option is
959 experimental and only available on a few boards. The device
960 tree is available in the global data as gd->fdt_blob.
962 U-Boot needs to get its device tree from somewhere. This can
963 be done using one of the two options below:
966 If this variable is defined, U-Boot will embed a device tree
967 binary in its image. This device tree file should be in the
968 board directory and called <soc>-<board>.dts. The binary file
969 is then picked up in board_init_f() and made available through
970 the global data structure as gd->blob.
973 If this variable is defined, U-Boot will build a device tree
974 binary. It will be called u-boot.dtb. Architecture-specific
975 code will locate it at run-time. Generally this works by:
977 cat u-boot.bin u-boot.dtb >image.bin
979 and in fact, U-Boot does this for you, creating a file called
980 u-boot-dtb.bin which is useful in the common case. You can
981 still use the individual files if you need something more
986 If this variable is defined, it enables watchdog
987 support for the SoC. There must be support in the SoC
988 specific code for a watchdog. For the 8xx and 8260
989 CPUs, the SIU Watchdog feature is enabled in the SYPCR
990 register. When supported for a specific SoC is
991 available, then no further board specific code should
995 When using a watchdog circuitry external to the used
996 SoC, then define this variable and provide board
997 specific code for the "hw_watchdog_reset" function.
1000 CONFIG_VERSION_VARIABLE
1001 If this variable is defined, an environment variable
1002 named "ver" is created by U-Boot showing the U-Boot
1003 version as printed by the "version" command.
1004 Any change to this variable will be reverted at the
1009 When CONFIG_CMD_DATE is selected, the type of the RTC
1010 has to be selected, too. Define exactly one of the
1013 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1014 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1015 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1016 CONFIG_RTC_MC146818 - use MC146818 RTC
1017 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1018 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1019 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1020 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1021 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1022 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1023 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1024 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1027 Note that if the RTC uses I2C, then the I2C interface
1028 must also be configured. See I2C Support, below.
1031 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1032 CONFIG_PCA953X_INFO - enable pca953x info command
1034 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1035 chip-ngpio pairs that tell the PCA953X driver the number of
1036 pins supported by a particular chip.
1038 Note that if the GPIO device uses I2C, then the I2C interface
1039 must also be configured. See I2C Support, below.
1041 - Timestamp Support:
1043 When CONFIG_TIMESTAMP is selected, the timestamp
1044 (date and time) of an image is printed by image
1045 commands like bootm or iminfo. This option is
1046 automatically enabled when you select CONFIG_CMD_DATE .
1048 - Partition Labels (disklabels) Supported:
1049 Zero or more of the following:
1050 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1051 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1052 Intel architecture, USB sticks, etc.
1053 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1054 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1055 bootloader. Note 2TB partition limit; see
1057 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1059 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1060 CONFIG_CMD_SCSI) you must configure support for at
1061 least one non-MTD partition type as well.
1064 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1065 board configurations files but used nowhere!
1067 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1068 be performed by calling the function
1069 ide_set_reset(int reset)
1070 which has to be defined in a board specific file
1075 Set this to enable ATAPI support.
1080 Set this to enable support for disks larger than 137GB
1081 Also look at CONFIG_SYS_64BIT_LBA.
1082 Whithout these , LBA48 support uses 32bit variables and will 'only'
1083 support disks up to 2.1TB.
1085 CONFIG_SYS_64BIT_LBA:
1086 When enabled, makes the IDE subsystem use 64bit sector addresses.
1090 At the moment only there is only support for the
1091 SYM53C8XX SCSI controller; define
1092 CONFIG_SCSI_SYM53C8XX to enable it.
1094 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1095 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1096 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1097 maximum numbers of LUNs, SCSI ID's and target
1099 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1101 The environment variable 'scsidevs' is set to the number of
1102 SCSI devices found during the last scan.
1104 - NETWORK Support (PCI):
1106 Support for Intel 8254x/8257x gigabit chips.
1109 Utility code for direct access to the SPI bus on Intel 8257x.
1110 This does not do anything useful unless you set at least one
1111 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1113 CONFIG_E1000_SPI_GENERIC
1114 Allow generic access to the SPI bus on the Intel 8257x, for
1115 example with the "sspi" command.
1118 Management command for E1000 devices. When used on devices
1119 with SPI support you can reprogram the EEPROM from U-Boot.
1121 CONFIG_E1000_FALLBACK_MAC
1122 default MAC for empty EEPROM after production.
1125 Support for Intel 82557/82559/82559ER chips.
1126 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1127 write routine for first time initialisation.
1130 Support for Digital 2114x chips.
1131 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1132 modem chip initialisation (KS8761/QS6611).
1135 Support for National dp83815 chips.
1138 Support for National dp8382[01] gigabit chips.
1140 - NETWORK Support (other):
1142 CONFIG_DRIVER_AT91EMAC
1143 Support for AT91RM9200 EMAC.
1146 Define this to use reduced MII inteface
1148 CONFIG_DRIVER_AT91EMAC_QUIET
1149 If this defined, the driver is quiet.
1150 The driver doen't show link status messages.
1152 CONFIG_CALXEDA_XGMAC
1153 Support for the Calxeda XGMAC device
1156 Support for SMSC's LAN91C96 chips.
1158 CONFIG_LAN91C96_BASE
1159 Define this to hold the physical address
1160 of the LAN91C96's I/O space
1162 CONFIG_LAN91C96_USE_32_BIT
1163 Define this to enable 32 bit addressing
1166 Support for SMSC's LAN91C111 chip
1168 CONFIG_SMC91111_BASE
1169 Define this to hold the physical address
1170 of the device (I/O space)
1172 CONFIG_SMC_USE_32_BIT
1173 Define this if data bus is 32 bits
1175 CONFIG_SMC_USE_IOFUNCS
1176 Define this to use i/o functions instead of macros
1177 (some hardware wont work with macros)
1179 CONFIG_DRIVER_TI_EMAC
1180 Support for davinci emac
1182 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1183 Define this if you have more then 3 PHYs.
1186 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1188 CONFIG_FTGMAC100_EGIGA
1189 Define this to use GE link update with gigabit PHY.
1190 Define this if FTGMAC100 is connected to gigabit PHY.
1191 If your system has 10/100 PHY only, it might not occur
1192 wrong behavior. Because PHY usually return timeout or
1193 useless data when polling gigabit status and gigabit
1194 control registers. This behavior won't affect the
1195 correctnessof 10/100 link speed update.
1198 Support for SMSC's LAN911x and LAN921x chips
1201 Define this to hold the physical address
1202 of the device (I/O space)
1204 CONFIG_SMC911X_32_BIT
1205 Define this if data bus is 32 bits
1207 CONFIG_SMC911X_16_BIT
1208 Define this if data bus is 16 bits. If your processor
1209 automatically converts one 32 bit word to two 16 bit
1210 words you may also try CONFIG_SMC911X_32_BIT.
1213 Support for Renesas on-chip Ethernet controller
1215 CONFIG_SH_ETHER_USE_PORT
1216 Define the number of ports to be used
1218 CONFIG_SH_ETHER_PHY_ADDR
1219 Define the ETH PHY's address
1221 CONFIG_SH_ETHER_CACHE_WRITEBACK
1222 If this option is set, the driver enables cache flush.
1226 Support TPM devices.
1229 Support for i2c bus TPM devices. Only one device
1230 per system is supported at this time.
1232 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1233 Define the the i2c bus number for the TPM device
1235 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1236 Define the TPM's address on the i2c bus
1238 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1239 Define the burst count bytes upper limit
1241 CONFIG_TPM_ATMEL_TWI
1242 Support for Atmel TWI TPM device. Requires I2C support.
1245 Support for generic parallel port TPM devices. Only one device
1246 per system is supported at this time.
1248 CONFIG_TPM_TIS_BASE_ADDRESS
1249 Base address where the generic TPM device is mapped
1250 to. Contemporary x86 systems usually map it at
1254 Add tpm monitor functions.
1255 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1256 provides monitor access to authorized functions.
1259 Define this to enable the TPM support library which provides
1260 functional interfaces to some TPM commands.
1261 Requires support for a TPM device.
1263 CONFIG_TPM_AUTH_SESSIONS
1264 Define this to enable authorized functions in the TPM library.
1265 Requires CONFIG_TPM and CONFIG_SHA1.
1268 At the moment only the UHCI host controller is
1269 supported (PIP405, MIP405, MPC5200); define
1270 CONFIG_USB_UHCI to enable it.
1271 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1272 and define CONFIG_USB_STORAGE to enable the USB
1275 Supported are USB Keyboards and USB Floppy drives
1277 MPC5200 USB requires additional defines:
1279 for 528 MHz Clock: 0x0001bbbb
1283 for differential drivers: 0x00001000
1284 for single ended drivers: 0x00005000
1285 for differential drivers on PSC3: 0x00000100
1286 for single ended drivers on PSC3: 0x00004100
1287 CONFIG_SYS_USB_EVENT_POLL
1288 May be defined to allow interrupt polling
1289 instead of using asynchronous interrupts
1291 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1292 txfilltuning field in the EHCI controller on reset.
1294 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1295 interval for usb hub power-on delay.(minimum 100msec)
1298 Define the below if you wish to use the USB console.
1299 Once firmware is rebuilt from a serial console issue the
1300 command "setenv stdin usbtty; setenv stdout usbtty" and
1301 attach your USB cable. The Unix command "dmesg" should print
1302 it has found a new device. The environment variable usbtty
1303 can be set to gserial or cdc_acm to enable your device to
1304 appear to a USB host as a Linux gserial device or a
1305 Common Device Class Abstract Control Model serial device.
1306 If you select usbtty = gserial you should be able to enumerate
1308 # modprobe usbserial vendor=0xVendorID product=0xProductID
1309 else if using cdc_acm, simply setting the environment
1310 variable usbtty to be cdc_acm should suffice. The following
1311 might be defined in YourBoardName.h
1314 Define this to build a UDC device
1317 Define this to have a tty type of device available to
1318 talk to the UDC device
1321 Define this to enable the high speed support for usb
1322 device and usbtty. If this feature is enabled, a routine
1323 int is_usbd_high_speed(void)
1324 also needs to be defined by the driver to dynamically poll
1325 whether the enumeration has succeded at high speed or full
1328 CONFIG_SYS_CONSOLE_IS_IN_ENV
1329 Define this if you want stdin, stdout &/or stderr to
1333 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1334 Derive USB clock from external clock "blah"
1335 - CONFIG_SYS_USB_EXTC_CLK 0x02
1337 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1338 Derive USB clock from brgclk
1339 - CONFIG_SYS_USB_BRG_CLK 0x04
1341 If you have a USB-IF assigned VendorID then you may wish to
1342 define your own vendor specific values either in BoardName.h
1343 or directly in usbd_vendor_info.h. If you don't define
1344 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1345 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1346 should pretend to be a Linux device to it's target host.
1348 CONFIG_USBD_MANUFACTURER
1349 Define this string as the name of your company for
1350 - CONFIG_USBD_MANUFACTURER "my company"
1352 CONFIG_USBD_PRODUCT_NAME
1353 Define this string as the name of your product
1354 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1356 CONFIG_USBD_VENDORID
1357 Define this as your assigned Vendor ID from the USB
1358 Implementors Forum. This *must* be a genuine Vendor ID
1359 to avoid polluting the USB namespace.
1360 - CONFIG_USBD_VENDORID 0xFFFF
1362 CONFIG_USBD_PRODUCTID
1363 Define this as the unique Product ID
1365 - CONFIG_USBD_PRODUCTID 0xFFFF
1367 - ULPI Layer Support:
1368 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1369 the generic ULPI layer. The generic layer accesses the ULPI PHY
1370 via the platform viewport, so you need both the genric layer and
1371 the viewport enabled. Currently only Chipidea/ARC based
1372 viewport is supported.
1373 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1374 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1375 If your ULPI phy needs a different reference clock than the
1376 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1377 the appropriate value in Hz.
1380 The MMC controller on the Intel PXA is supported. To
1381 enable this define CONFIG_MMC. The MMC can be
1382 accessed from the boot prompt by mapping the device
1383 to physical memory similar to flash. Command line is
1384 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1385 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1388 Support for Renesas on-chip MMCIF controller
1390 CONFIG_SH_MMCIF_ADDR
1391 Define the base address of MMCIF registers
1394 Define the clock frequency for MMCIF
1396 - USB Device Firmware Update (DFU) class support:
1398 This enables the USB portion of the DFU USB class
1401 This enables the command "dfu" which is used to have
1402 U-Boot create a DFU class device via USB. This command
1403 requires that the "dfu_alt_info" environment variable be
1404 set and define the alt settings to expose to the host.
1407 This enables support for exposing (e)MMC devices via DFU.
1410 This enables support for exposing NAND devices via DFU.
1412 CONFIG_SYS_DFU_DATA_BUF_SIZE
1413 Dfu transfer uses a buffer before writing data to the
1414 raw storage device. Make the size (in bytes) of this buffer
1415 configurable. The size of this buffer is also configurable
1416 through the "dfu_bufsiz" environment variable.
1418 CONFIG_SYS_DFU_MAX_FILE_SIZE
1419 When updating files rather than the raw storage device,
1420 we use a static buffer to copy the file into and then write
1421 the buffer once we've been given the whole file. Define
1422 this to the maximum filesize (in bytes) for the buffer.
1423 Default is 4 MiB if undefined.
1425 - Journaling Flash filesystem support:
1426 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1427 CONFIG_JFFS2_NAND_DEV
1428 Define these for a default partition on a NAND device
1430 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1431 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1432 Define these for a default partition on a NOR device
1434 CONFIG_SYS_JFFS_CUSTOM_PART
1435 Define this to create an own partition. You have to provide a
1436 function struct part_info* jffs2_part_info(int part_num)
1438 If you define only one JFFS2 partition you may also want to
1439 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1440 to disable the command chpart. This is the default when you
1441 have not defined a custom partition
1443 - FAT(File Allocation Table) filesystem write function support:
1446 Define this to enable support for saving memory data as a
1447 file in FAT formatted partition.
1449 This will also enable the command "fatwrite" enabling the
1450 user to write files to FAT.
1452 CBFS (Coreboot Filesystem) support
1455 Define this to enable support for reading from a Coreboot
1456 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1462 Define this to enable standard (PC-Style) keyboard
1466 Standard PC keyboard driver with US (is default) and
1467 GERMAN key layout (switch via environment 'keymap=de') support.
1468 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1469 for cfb_console. Supports cursor blinking.
1472 Enables a Chrome OS keyboard using the CROS_EC interface.
1473 This uses CROS_EC to communicate with a second microcontroller
1474 which provides key scans on request.
1479 Define this to enable video support (for output to
1482 CONFIG_VIDEO_CT69000
1484 Enable Chips & Technologies 69000 Video chip
1486 CONFIG_VIDEO_SMI_LYNXEM
1487 Enable Silicon Motion SMI 712/710/810 Video chip. The
1488 video output is selected via environment 'videoout'
1489 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1492 For the CT69000 and SMI_LYNXEM drivers, videomode is
1493 selected via environment 'videomode'. Two different ways
1495 - "videomode=num" 'num' is a standard LiLo mode numbers.
1496 Following standard modes are supported (* is default):
1498 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1499 -------------+---------------------------------------------
1500 8 bits | 0x301* 0x303 0x305 0x161 0x307
1501 15 bits | 0x310 0x313 0x316 0x162 0x319
1502 16 bits | 0x311 0x314 0x317 0x163 0x31A
1503 24 bits | 0x312 0x315 0x318 ? 0x31B
1504 -------------+---------------------------------------------
1505 (i.e. setenv videomode 317; saveenv; reset;)
1507 - "videomode=bootargs" all the video parameters are parsed
1508 from the bootargs. (See drivers/video/videomodes.c)
1511 CONFIG_VIDEO_SED13806
1512 Enable Epson SED13806 driver. This driver supports 8bpp
1513 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1514 or CONFIG_VIDEO_SED13806_16BPP
1517 Enable the Freescale DIU video driver. Reference boards for
1518 SOCs that have a DIU should define this macro to enable DIU
1519 support, and should also define these other macros:
1525 CONFIG_VIDEO_SW_CURSOR
1526 CONFIG_VGA_AS_SINGLE_DEVICE
1528 CONFIG_VIDEO_BMP_LOGO
1530 The DIU driver will look for the 'video-mode' environment
1531 variable, and if defined, enable the DIU as a console during
1532 boot. See the documentation file README.video for a
1533 description of this variable.
1537 Enable the VGA video / BIOS for x86. The alternative if you
1538 are using coreboot is to use the coreboot frame buffer
1545 Define this to enable a custom keyboard support.
1546 This simply calls drv_keyboard_init() which must be
1547 defined in your board-specific files.
1548 The only board using this so far is RBC823.
1550 - LCD Support: CONFIG_LCD
1552 Define this to enable LCD support (for output to LCD
1553 display); also select one of the supported displays
1554 by defining one of these:
1558 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1560 CONFIG_NEC_NL6448AC33:
1562 NEC NL6448AC33-18. Active, color, single scan.
1564 CONFIG_NEC_NL6448BC20
1566 NEC NL6448BC20-08. 6.5", 640x480.
1567 Active, color, single scan.
1569 CONFIG_NEC_NL6448BC33_54
1571 NEC NL6448BC33-54. 10.4", 640x480.
1572 Active, color, single scan.
1576 Sharp 320x240. Active, color, single scan.
1577 It isn't 16x9, and I am not sure what it is.
1579 CONFIG_SHARP_LQ64D341
1581 Sharp LQ64D341 display, 640x480.
1582 Active, color, single scan.
1586 HLD1045 display, 640x480.
1587 Active, color, single scan.
1591 Optrex CBL50840-2 NF-FW 99 22 M5
1593 Hitachi LMG6912RPFC-00T
1597 320x240. Black & white.
1599 Normally display is black on white background; define
1600 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1602 CONFIG_LCD_ALIGNMENT
1604 Normally the LCD is page-aligned (tyically 4KB). If this is
1605 defined then the LCD will be aligned to this value instead.
1606 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1607 here, since it is cheaper to change data cache settings on
1608 a per-section basis.
1610 CONFIG_CONSOLE_SCROLL_LINES
1612 When the console need to be scrolled, this is the number of
1613 lines to scroll by. It defaults to 1. Increasing this makes
1614 the console jump but can help speed up operation when scrolling
1619 Support drawing of RLE8-compressed bitmaps on the LCD.
1623 Enables an 'i2c edid' command which can read EDID
1624 information over I2C from an attached LCD display.
1626 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1628 If this option is set, the environment is checked for
1629 a variable "splashimage". If found, the usual display
1630 of logo, copyright and system information on the LCD
1631 is suppressed and the BMP image at the address
1632 specified in "splashimage" is loaded instead. The
1633 console is redirected to the "nulldev", too. This
1634 allows for a "silent" boot where a splash screen is
1635 loaded very quickly after power-on.
1637 CONFIG_SPLASHIMAGE_GUARD
1639 If this option is set, then U-Boot will prevent the environment
1640 variable "splashimage" from being set to a problematic address
1641 (see README.displaying-bmps and README.arm-unaligned-accesses).
1642 This option is useful for targets where, due to alignment
1643 restrictions, an improperly aligned BMP image will cause a data
1644 abort. If you think you will not have problems with unaligned
1645 accesses (for example because your toolchain prevents them)
1646 there is no need to set this option.
1648 CONFIG_SPLASH_SCREEN_ALIGN
1650 If this option is set the splash image can be freely positioned
1651 on the screen. Environment variable "splashpos" specifies the
1652 position as "x,y". If a positive number is given it is used as
1653 number of pixel from left/top. If a negative number is given it
1654 is used as number of pixel from right/bottom. You can also
1655 specify 'm' for centering the image.
1658 setenv splashpos m,m
1659 => image at center of screen
1661 setenv splashpos 30,20
1662 => image at x = 30 and y = 20
1664 setenv splashpos -10,m
1665 => vertically centered image
1666 at x = dspWidth - bmpWidth - 9
1668 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1670 If this option is set, additionally to standard BMP
1671 images, gzipped BMP images can be displayed via the
1672 splashscreen support or the bmp command.
1674 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1676 If this option is set, 8-bit RLE compressed BMP images
1677 can be displayed via the splashscreen support or the
1680 - Do compresssing for memory range:
1683 If this option is set, it would use zlib deflate method
1684 to compress the specified memory at its best effort.
1686 - Compression support:
1689 If this option is set, support for bzip2 compressed
1690 images is included. If not, only uncompressed and gzip
1691 compressed images are supported.
1693 NOTE: the bzip2 algorithm requires a lot of RAM, so
1694 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1699 If this option is set, support for lzma compressed
1702 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1703 requires an amount of dynamic memory that is given by the
1706 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1708 Where lc and lp stand for, respectively, Literal context bits
1709 and Literal pos bits.
1711 This value is upper-bounded by 14MB in the worst case. Anyway,
1712 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1713 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1714 a very small buffer.
1716 Use the lzmainfo tool to determinate the lc and lp values and
1717 then calculate the amount of needed dynamic memory (ensuring
1718 the appropriate CONFIG_SYS_MALLOC_LEN value).
1723 The address of PHY on MII bus.
1725 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1727 The clock frequency of the MII bus
1731 If this option is set, support for speed/duplex
1732 detection of gigabit PHY is included.
1734 CONFIG_PHY_RESET_DELAY
1736 Some PHY like Intel LXT971A need extra delay after
1737 reset before any MII register access is possible.
1738 For such PHY, set this option to the usec delay
1739 required. (minimum 300usec for LXT971A)
1741 CONFIG_PHY_CMD_DELAY (ppc4xx)
1743 Some PHY like Intel LXT971A need extra delay after
1744 command issued before MII status register can be read
1754 Define a default value for Ethernet address to use
1755 for the respective Ethernet interface, in case this
1756 is not determined automatically.
1761 Define a default value for the IP address to use for
1762 the default Ethernet interface, in case this is not
1763 determined through e.g. bootp.
1764 (Environment variable "ipaddr")
1766 - Server IP address:
1769 Defines a default value for the IP address of a TFTP
1770 server to contact when using the "tftboot" command.
1771 (Environment variable "serverip")
1773 CONFIG_KEEP_SERVERADDR
1775 Keeps the server's MAC address, in the env 'serveraddr'
1776 for passing to bootargs (like Linux's netconsole option)
1778 - Gateway IP address:
1781 Defines a default value for the IP address of the
1782 default router where packets to other networks are
1784 (Environment variable "gatewayip")
1789 Defines a default value for the subnet mask (or
1790 routing prefix) which is used to determine if an IP
1791 address belongs to the local subnet or needs to be
1792 forwarded through a router.
1793 (Environment variable "netmask")
1795 - Multicast TFTP Mode:
1798 Defines whether you want to support multicast TFTP as per
1799 rfc-2090; for example to work with atftp. Lets lots of targets
1800 tftp down the same boot image concurrently. Note: the Ethernet
1801 driver in use must provide a function: mcast() to join/leave a
1804 - BOOTP Recovery Mode:
1805 CONFIG_BOOTP_RANDOM_DELAY
1807 If you have many targets in a network that try to
1808 boot using BOOTP, you may want to avoid that all
1809 systems send out BOOTP requests at precisely the same
1810 moment (which would happen for instance at recovery
1811 from a power failure, when all systems will try to
1812 boot, thus flooding the BOOTP server. Defining
1813 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1814 inserted before sending out BOOTP requests. The
1815 following delays are inserted then:
1817 1st BOOTP request: delay 0 ... 1 sec
1818 2nd BOOTP request: delay 0 ... 2 sec
1819 3rd BOOTP request: delay 0 ... 4 sec
1821 BOOTP requests: delay 0 ... 8 sec
1823 - DHCP Advanced Options:
1824 You can fine tune the DHCP functionality by defining
1825 CONFIG_BOOTP_* symbols:
1827 CONFIG_BOOTP_SUBNETMASK
1828 CONFIG_BOOTP_GATEWAY
1829 CONFIG_BOOTP_HOSTNAME
1830 CONFIG_BOOTP_NISDOMAIN
1831 CONFIG_BOOTP_BOOTPATH
1832 CONFIG_BOOTP_BOOTFILESIZE
1835 CONFIG_BOOTP_SEND_HOSTNAME
1836 CONFIG_BOOTP_NTPSERVER
1837 CONFIG_BOOTP_TIMEOFFSET
1838 CONFIG_BOOTP_VENDOREX
1839 CONFIG_BOOTP_MAY_FAIL
1841 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1842 environment variable, not the BOOTP server.
1844 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1845 after the configured retry count, the call will fail
1846 instead of starting over. This can be used to fail over
1847 to Link-local IP address configuration if the DHCP server
1850 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1851 serverip from a DHCP server, it is possible that more
1852 than one DNS serverip is offered to the client.
1853 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1854 serverip will be stored in the additional environment
1855 variable "dnsip2". The first DNS serverip is always
1856 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1859 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1860 to do a dynamic update of a DNS server. To do this, they
1861 need the hostname of the DHCP requester.
1862 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1863 of the "hostname" environment variable is passed as
1864 option 12 to the DHCP server.
1866 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1868 A 32bit value in microseconds for a delay between
1869 receiving a "DHCP Offer" and sending the "DHCP Request".
1870 This fixes a problem with certain DHCP servers that don't
1871 respond 100% of the time to a "DHCP request". E.g. On an
1872 AT91RM9200 processor running at 180MHz, this delay needed
1873 to be *at least* 15,000 usec before a Windows Server 2003
1874 DHCP server would reply 100% of the time. I recommend at
1875 least 50,000 usec to be safe. The alternative is to hope
1876 that one of the retries will be successful but note that
1877 the DHCP timeout and retry process takes a longer than
1880 - Link-local IP address negotiation:
1881 Negotiate with other link-local clients on the local network
1882 for an address that doesn't require explicit configuration.
1883 This is especially useful if a DHCP server cannot be guaranteed
1884 to exist in all environments that the device must operate.
1886 See doc/README.link-local for more information.
1889 CONFIG_CDP_DEVICE_ID
1891 The device id used in CDP trigger frames.
1893 CONFIG_CDP_DEVICE_ID_PREFIX
1895 A two character string which is prefixed to the MAC address
1900 A printf format string which contains the ascii name of
1901 the port. Normally is set to "eth%d" which sets
1902 eth0 for the first Ethernet, eth1 for the second etc.
1904 CONFIG_CDP_CAPABILITIES
1906 A 32bit integer which indicates the device capabilities;
1907 0x00000010 for a normal host which does not forwards.
1911 An ascii string containing the version of the software.
1915 An ascii string containing the name of the platform.
1919 A 32bit integer sent on the trigger.
1921 CONFIG_CDP_POWER_CONSUMPTION
1923 A 16bit integer containing the power consumption of the
1924 device in .1 of milliwatts.
1926 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1928 A byte containing the id of the VLAN.
1930 - Status LED: CONFIG_STATUS_LED
1932 Several configurations allow to display the current
1933 status using a LED. For instance, the LED will blink
1934 fast while running U-Boot code, stop blinking as
1935 soon as a reply to a BOOTP request was received, and
1936 start blinking slow once the Linux kernel is running
1937 (supported by a status LED driver in the Linux
1938 kernel). Defining CONFIG_STATUS_LED enables this
1941 - CAN Support: CONFIG_CAN_DRIVER
1943 Defining CONFIG_CAN_DRIVER enables CAN driver support
1944 on those systems that support this (optional)
1945 feature, like the TQM8xxL modules.
1947 - I2C Support: CONFIG_SYS_I2C
1949 This enable the NEW i2c subsystem, and will allow you to use
1950 i2c commands at the u-boot command line (as long as you set
1951 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1952 based realtime clock chips or other i2c devices. See
1953 common/cmd_i2c.c for a description of the command line
1956 ported i2c driver to the new framework:
1957 - drivers/i2c/soft_i2c.c:
1958 - activate first bus with CONFIG_SYS_I2C_SOFT define
1959 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1960 for defining speed and slave address
1961 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1962 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1963 for defining speed and slave address
1964 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1965 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1966 for defining speed and slave address
1967 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1968 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1969 for defining speed and slave address
1971 - drivers/i2c/fsl_i2c.c:
1972 - activate i2c driver with CONFIG_SYS_I2C_FSL
1973 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1974 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1975 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1977 - If your board supports a second fsl i2c bus, define
1978 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1979 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1980 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1985 CONFIG_SYS_NUM_I2C_BUSES
1986 Hold the number of i2c busses you want to use. If you
1987 don't use/have i2c muxes on your i2c bus, this
1988 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
1991 CONFIG_SYS_I2C_DIRECT_BUS
1992 define this, if you don't use i2c muxes on your hardware.
1993 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1996 CONFIG_SYS_I2C_MAX_HOPS
1997 define how many muxes are maximal consecutively connected
1998 on one i2c bus. If you not use i2c muxes, omit this
2001 CONFIG_SYS_I2C_BUSES
2002 hold a list of busses you want to use, only used if
2003 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2004 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2005 CONFIG_SYS_NUM_I2C_BUSES = 9:
2007 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2008 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2009 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2010 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2011 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2012 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2013 {1, {I2C_NULL_HOP}}, \
2014 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2015 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2019 bus 0 on adapter 0 without a mux
2020 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2021 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2022 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2023 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2024 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2025 bus 6 on adapter 1 without a mux
2026 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2027 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2029 If you do not have i2c muxes on your board, omit this define.
2031 - Legacy I2C Support: CONFIG_HARD_I2C
2033 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2034 provides the following compelling advantages:
2036 - more than one i2c adapter is usable
2037 - approved multibus support
2038 - better i2c mux support
2040 ** Please consider updating your I2C driver now. **
2042 These enable legacy I2C serial bus commands. Defining
2043 CONFIG_HARD_I2C will include the appropriate I2C driver
2044 for the selected CPU.
2046 This will allow you to use i2c commands at the u-boot
2047 command line (as long as you set CONFIG_CMD_I2C in
2048 CONFIG_COMMANDS) and communicate with i2c based realtime
2049 clock chips. See common/cmd_i2c.c for a description of the
2050 command line interface.
2052 CONFIG_HARD_I2C selects a hardware I2C controller.
2054 There are several other quantities that must also be
2055 defined when you define CONFIG_HARD_I2C.
2057 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2058 to be the frequency (in Hz) at which you wish your i2c bus
2059 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2060 the CPU's i2c node address).
2062 Now, the u-boot i2c code for the mpc8xx
2063 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2064 and so its address should therefore be cleared to 0 (See,
2065 eg, MPC823e User's Manual p.16-473). So, set
2066 CONFIG_SYS_I2C_SLAVE to 0.
2068 CONFIG_SYS_I2C_INIT_MPC5XXX
2070 When a board is reset during an i2c bus transfer
2071 chips might think that the current transfer is still
2072 in progress. Reset the slave devices by sending start
2073 commands until the slave device responds.
2075 That's all that's required for CONFIG_HARD_I2C.
2077 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2078 then the following macros need to be defined (examples are
2079 from include/configs/lwmon.h):
2083 (Optional). Any commands necessary to enable the I2C
2084 controller or configure ports.
2086 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2090 (Only for MPC8260 CPU). The I/O port to use (the code
2091 assumes both bits are on the same port). Valid values
2092 are 0..3 for ports A..D.
2096 The code necessary to make the I2C data line active
2097 (driven). If the data line is open collector, this
2100 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2104 The code necessary to make the I2C data line tri-stated
2105 (inactive). If the data line is open collector, this
2108 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2112 Code that returns true if the I2C data line is high,
2115 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2119 If <bit> is true, sets the I2C data line high. If it
2120 is false, it clears it (low).
2122 eg: #define I2C_SDA(bit) \
2123 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2124 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2128 If <bit> is true, sets the I2C clock line high. If it
2129 is false, it clears it (low).
2131 eg: #define I2C_SCL(bit) \
2132 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2133 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2137 This delay is invoked four times per clock cycle so this
2138 controls the rate of data transfer. The data rate thus
2139 is 1 / (I2C_DELAY * 4). Often defined to be something
2142 #define I2C_DELAY udelay(2)
2144 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2146 If your arch supports the generic GPIO framework (asm/gpio.h),
2147 then you may alternatively define the two GPIOs that are to be
2148 used as SCL / SDA. Any of the previous I2C_xxx macros will
2149 have GPIO-based defaults assigned to them as appropriate.
2151 You should define these to the GPIO value as given directly to
2152 the generic GPIO functions.
2154 CONFIG_SYS_I2C_INIT_BOARD
2156 When a board is reset during an i2c bus transfer
2157 chips might think that the current transfer is still
2158 in progress. On some boards it is possible to access
2159 the i2c SCLK line directly, either by using the
2160 processor pin as a GPIO or by having a second pin
2161 connected to the bus. If this option is defined a
2162 custom i2c_init_board() routine in boards/xxx/board.c
2163 is run early in the boot sequence.
2165 CONFIG_SYS_I2C_BOARD_LATE_INIT
2167 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2168 defined a custom i2c_board_late_init() routine in
2169 boards/xxx/board.c is run AFTER the operations in i2c_init()
2170 is completed. This callpoint can be used to unreset i2c bus
2171 using CPU i2c controller register accesses for CPUs whose i2c
2172 controller provide such a method. It is called at the end of
2173 i2c_init() to allow i2c_init operations to setup the i2c bus
2174 controller on the CPU (e.g. setting bus speed & slave address).
2176 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2178 This option enables configuration of bi_iic_fast[] flags
2179 in u-boot bd_info structure based on u-boot environment
2180 variable "i2cfast". (see also i2cfast)
2182 CONFIG_I2C_MULTI_BUS
2184 This option allows the use of multiple I2C buses, each of which
2185 must have a controller. At any point in time, only one bus is
2186 active. To switch to a different bus, use the 'i2c dev' command.
2187 Note that bus numbering is zero-based.
2189 CONFIG_SYS_I2C_NOPROBES
2191 This option specifies a list of I2C devices that will be skipped
2192 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2193 is set, specify a list of bus-device pairs. Otherwise, specify
2194 a 1D array of device addresses
2197 #undef CONFIG_I2C_MULTI_BUS
2198 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2200 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2202 #define CONFIG_I2C_MULTI_BUS
2203 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2205 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2207 CONFIG_SYS_SPD_BUS_NUM
2209 If defined, then this indicates the I2C bus number for DDR SPD.
2210 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2212 CONFIG_SYS_RTC_BUS_NUM
2214 If defined, then this indicates the I2C bus number for the RTC.
2215 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2217 CONFIG_SYS_DTT_BUS_NUM
2219 If defined, then this indicates the I2C bus number for the DTT.
2220 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2222 CONFIG_SYS_I2C_DTT_ADDR:
2224 If defined, specifies the I2C address of the DTT device.
2225 If not defined, then U-Boot uses predefined value for
2226 specified DTT device.
2230 Define this option if you have I2C devices reached over 1 .. n
2231 I2C Muxes like the pca9544a. This option addes a new I2C
2232 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
2233 new I2C Bus to the existing I2C Busses. If you select the
2234 new Bus with "i2c dev", u-bbot sends first the commandos for
2235 the muxes to activate this new "bus".
2237 CONFIG_I2C_MULTI_BUS must be also defined, to use this
2241 Adding a new I2C Bus reached over 2 pca9544a muxes
2242 The First mux with address 70 and channel 6
2243 The Second mux with address 71 and channel 4
2245 => i2c bus pca9544a:70:6:pca9544a:71:4
2247 Use the "i2c bus" command without parameter, to get a list
2248 of I2C Busses with muxes:
2251 Busses reached over muxes:
2253 reached over Mux(es):
2256 reached over Mux(es):
2261 If you now switch to the new I2C Bus 3 with "i2c dev 3"
2262 u-boot first sends the command to the mux@70 to enable
2263 channel 6, and then the command to the mux@71 to enable
2266 After that, you can use the "normal" i2c commands as
2267 usual to communicate with your I2C devices behind
2270 This option is actually implemented for the bitbanging
2271 algorithm in common/soft_i2c.c and for the Hardware I2C
2272 Bus on the MPC8260. But it should be not so difficult
2273 to add this option to other architectures.
2275 CONFIG_SOFT_I2C_READ_REPEATED_START
2277 defining this will force the i2c_read() function in
2278 the soft_i2c driver to perform an I2C repeated start
2279 between writing the address pointer and reading the
2280 data. If this define is omitted the default behaviour
2281 of doing a stop-start sequence will be used. Most I2C
2282 devices can use either method, but some require one or
2285 - SPI Support: CONFIG_SPI
2287 Enables SPI driver (so far only tested with
2288 SPI EEPROM, also an instance works with Crystal A/D and
2289 D/As on the SACSng board)
2293 Enables the driver for SPI controller on SuperH. Currently
2294 only SH7757 is supported.
2298 Enables extended (16-bit) SPI EEPROM addressing.
2299 (symmetrical to CONFIG_I2C_X)
2303 Enables a software (bit-bang) SPI driver rather than
2304 using hardware support. This is a general purpose
2305 driver that only requires three general I/O port pins
2306 (two outputs, one input) to function. If this is
2307 defined, the board configuration must define several
2308 SPI configuration items (port pins to use, etc). For
2309 an example, see include/configs/sacsng.h.
2313 Enables a hardware SPI driver for general-purpose reads
2314 and writes. As with CONFIG_SOFT_SPI, the board configuration
2315 must define a list of chip-select function pointers.
2316 Currently supported on some MPC8xxx processors. For an
2317 example, see include/configs/mpc8349emds.h.
2321 Enables the driver for the SPI controllers on i.MX and MXC
2322 SoCs. Currently i.MX31/35/51 are supported.
2324 - FPGA Support: CONFIG_FPGA
2326 Enables FPGA subsystem.
2328 CONFIG_FPGA_<vendor>
2330 Enables support for specific chip vendors.
2333 CONFIG_FPGA_<family>
2335 Enables support for FPGA family.
2336 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2340 Specify the number of FPGA devices to support.
2342 CONFIG_SYS_FPGA_PROG_FEEDBACK
2344 Enable printing of hash marks during FPGA configuration.
2346 CONFIG_SYS_FPGA_CHECK_BUSY
2348 Enable checks on FPGA configuration interface busy
2349 status by the configuration function. This option
2350 will require a board or device specific function to
2355 If defined, a function that provides delays in the FPGA
2356 configuration driver.
2358 CONFIG_SYS_FPGA_CHECK_CTRLC
2359 Allow Control-C to interrupt FPGA configuration
2361 CONFIG_SYS_FPGA_CHECK_ERROR
2363 Check for configuration errors during FPGA bitfile
2364 loading. For example, abort during Virtex II
2365 configuration if the INIT_B line goes low (which
2366 indicated a CRC error).
2368 CONFIG_SYS_FPGA_WAIT_INIT
2370 Maximum time to wait for the INIT_B line to deassert
2371 after PROB_B has been deasserted during a Virtex II
2372 FPGA configuration sequence. The default time is 500
2375 CONFIG_SYS_FPGA_WAIT_BUSY
2377 Maximum time to wait for BUSY to deassert during
2378 Virtex II FPGA configuration. The default is 5 ms.
2380 CONFIG_SYS_FPGA_WAIT_CONFIG
2382 Time to wait after FPGA configuration. The default is
2385 - Configuration Management:
2388 If defined, this string will be added to the U-Boot
2389 version information (U_BOOT_VERSION)
2391 - Vendor Parameter Protection:
2393 U-Boot considers the values of the environment
2394 variables "serial#" (Board Serial Number) and
2395 "ethaddr" (Ethernet Address) to be parameters that
2396 are set once by the board vendor / manufacturer, and
2397 protects these variables from casual modification by
2398 the user. Once set, these variables are read-only,
2399 and write or delete attempts are rejected. You can
2400 change this behaviour:
2402 If CONFIG_ENV_OVERWRITE is #defined in your config
2403 file, the write protection for vendor parameters is
2404 completely disabled. Anybody can change or delete
2407 Alternatively, if you #define _both_ CONFIG_ETHADDR
2408 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2409 Ethernet address is installed in the environment,
2410 which can be changed exactly ONCE by the user. [The
2411 serial# is unaffected by this, i. e. it remains
2414 The same can be accomplished in a more flexible way
2415 for any variable by configuring the type of access
2416 to allow for those variables in the ".flags" variable
2417 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2422 Define this variable to enable the reservation of
2423 "protected RAM", i. e. RAM which is not overwritten
2424 by U-Boot. Define CONFIG_PRAM to hold the number of
2425 kB you want to reserve for pRAM. You can overwrite
2426 this default value by defining an environment
2427 variable "pram" to the number of kB you want to
2428 reserve. Note that the board info structure will
2429 still show the full amount of RAM. If pRAM is
2430 reserved, a new environment variable "mem" will
2431 automatically be defined to hold the amount of
2432 remaining RAM in a form that can be passed as boot
2433 argument to Linux, for instance like that:
2435 setenv bootargs ... mem=\${mem}
2438 This way you can tell Linux not to use this memory,
2439 either, which results in a memory region that will
2440 not be affected by reboots.
2442 *WARNING* If your board configuration uses automatic
2443 detection of the RAM size, you must make sure that
2444 this memory test is non-destructive. So far, the
2445 following board configurations are known to be
2448 IVMS8, IVML24, SPD8xx, TQM8xxL,
2449 HERMES, IP860, RPXlite, LWMON,
2452 - Access to physical memory region (> 4GB)
2453 Some basic support is provided for operations on memory not
2454 normally accessible to U-Boot - e.g. some architectures
2455 support access to more than 4GB of memory on 32-bit
2456 machines using physical address extension or similar.
2457 Define CONFIG_PHYSMEM to access this basic support, which
2458 currently only supports clearing the memory.
2463 Define this variable to stop the system in case of a
2464 fatal error, so that you have to reset it manually.
2465 This is probably NOT a good idea for an embedded
2466 system where you want the system to reboot
2467 automatically as fast as possible, but it may be
2468 useful during development since you can try to debug
2469 the conditions that lead to the situation.
2471 CONFIG_NET_RETRY_COUNT
2473 This variable defines the number of retries for
2474 network operations like ARP, RARP, TFTP, or BOOTP
2475 before giving up the operation. If not defined, a
2476 default value of 5 is used.
2480 Timeout waiting for an ARP reply in milliseconds.
2484 Timeout in milliseconds used in NFS protocol.
2485 If you encounter "ERROR: Cannot umount" in nfs command,
2486 try longer timeout such as
2487 #define CONFIG_NFS_TIMEOUT 10000UL
2489 - Command Interpreter:
2490 CONFIG_AUTO_COMPLETE
2492 Enable auto completion of commands using TAB.
2494 Note that this feature has NOT been implemented yet
2495 for the "hush" shell.
2498 CONFIG_SYS_HUSH_PARSER
2500 Define this variable to enable the "hush" shell (from
2501 Busybox) as command line interpreter, thus enabling
2502 powerful command line syntax like
2503 if...then...else...fi conditionals or `&&' and '||'
2504 constructs ("shell scripts").
2506 If undefined, you get the old, much simpler behaviour
2507 with a somewhat smaller memory footprint.
2510 CONFIG_SYS_PROMPT_HUSH_PS2
2512 This defines the secondary prompt string, which is
2513 printed when the command interpreter needs more input
2514 to complete a command. Usually "> ".
2518 In the current implementation, the local variables
2519 space and global environment variables space are
2520 separated. Local variables are those you define by
2521 simply typing `name=value'. To access a local
2522 variable later on, you have write `$name' or
2523 `${name}'; to execute the contents of a variable
2524 directly type `$name' at the command prompt.
2526 Global environment variables are those you use
2527 setenv/printenv to work with. To run a command stored
2528 in such a variable, you need to use the run command,
2529 and you must not use the '$' sign to access them.
2531 To store commands and special characters in a
2532 variable, please use double quotation marks
2533 surrounding the whole text of the variable, instead
2534 of the backslashes before semicolons and special
2537 - Commandline Editing and History:
2538 CONFIG_CMDLINE_EDITING
2540 Enable editing and History functions for interactive
2541 commandline input operations
2543 - Default Environment:
2544 CONFIG_EXTRA_ENV_SETTINGS
2546 Define this to contain any number of null terminated
2547 strings (variable = value pairs) that will be part of
2548 the default environment compiled into the boot image.
2550 For example, place something like this in your
2551 board's config file:
2553 #define CONFIG_EXTRA_ENV_SETTINGS \
2557 Warning: This method is based on knowledge about the
2558 internal format how the environment is stored by the
2559 U-Boot code. This is NOT an official, exported
2560 interface! Although it is unlikely that this format
2561 will change soon, there is no guarantee either.
2562 You better know what you are doing here.
2564 Note: overly (ab)use of the default environment is
2565 discouraged. Make sure to check other ways to preset
2566 the environment like the "source" command or the
2569 CONFIG_ENV_VARS_UBOOT_CONFIG
2571 Define this in order to add variables describing the
2572 U-Boot build configuration to the default environment.
2573 These will be named arch, cpu, board, vendor, and soc.
2575 Enabling this option will cause the following to be defined:
2583 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2585 Define this in order to add variables describing certain
2586 run-time determined information about the hardware to the
2587 environment. These will be named board_name, board_rev.
2589 CONFIG_DELAY_ENVIRONMENT
2591 Normally the environment is loaded when the board is
2592 intialised so that it is available to U-Boot. This inhibits
2593 that so that the environment is not available until
2594 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2595 this is instead controlled by the value of
2596 /config/load-environment.
2598 - DataFlash Support:
2599 CONFIG_HAS_DATAFLASH
2601 Defining this option enables DataFlash features and
2602 allows to read/write in Dataflash via the standard
2605 - Serial Flash support
2608 Defining this option enables SPI flash commands
2609 'sf probe/read/write/erase/update'.
2611 Usage requires an initial 'probe' to define the serial
2612 flash parameters, followed by read/write/erase/update
2615 The following defaults may be provided by the platform
2616 to handle the common case when only a single serial
2617 flash is present on the system.
2619 CONFIG_SF_DEFAULT_BUS Bus identifier
2620 CONFIG_SF_DEFAULT_CS Chip-select
2621 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2622 CONFIG_SF_DEFAULT_SPEED in Hz
2626 Define this option to include a destructive SPI flash
2629 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2631 Define this option to use the Bank addr/Extended addr
2632 support on SPI flashes which has size > 16Mbytes.
2634 - SystemACE Support:
2637 Adding this option adds support for Xilinx SystemACE
2638 chips attached via some sort of local bus. The address
2639 of the chip must also be defined in the
2640 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2642 #define CONFIG_SYSTEMACE
2643 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2645 When SystemACE support is added, the "ace" device type
2646 becomes available to the fat commands, i.e. fatls.
2648 - TFTP Fixed UDP Port:
2651 If this is defined, the environment variable tftpsrcp
2652 is used to supply the TFTP UDP source port value.
2653 If tftpsrcp isn't defined, the normal pseudo-random port
2654 number generator is used.
2656 Also, the environment variable tftpdstp is used to supply
2657 the TFTP UDP destination port value. If tftpdstp isn't
2658 defined, the normal port 69 is used.
2660 The purpose for tftpsrcp is to allow a TFTP server to
2661 blindly start the TFTP transfer using the pre-configured
2662 target IP address and UDP port. This has the effect of
2663 "punching through" the (Windows XP) firewall, allowing
2664 the remainder of the TFTP transfer to proceed normally.
2665 A better solution is to properly configure the firewall,
2666 but sometimes that is not allowed.
2671 This enables a generic 'hash' command which can produce
2672 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2676 Enable the hash verify command (hash -v). This adds to code
2679 CONFIG_SHA1 - support SHA1 hashing
2680 CONFIG_SHA256 - support SHA256 hashing
2682 Note: There is also a sha1sum command, which should perhaps
2683 be deprecated in favour of 'hash sha1'.
2688 This enables the RSA algorithm used for FIT image verification
2689 in U-Boot. See doc/uImage/signature for more information.
2691 The signing part is build into mkimage regardless of this
2695 - Show boot progress:
2696 CONFIG_SHOW_BOOT_PROGRESS
2698 Defining this option allows to add some board-
2699 specific code (calling a user-provided function
2700 "show_boot_progress(int)") that enables you to show
2701 the system's boot progress on some display (for
2702 example, some LED's) on your board. At the moment,
2703 the following checkpoints are implemented:
2705 - Detailed boot stage timing
2707 Define this option to get detailed timing of each stage
2708 of the boot process.
2710 CONFIG_BOOTSTAGE_USER_COUNT
2711 This is the number of available user bootstage records.
2712 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2713 a new ID will be allocated from this stash. If you exceed
2714 the limit, recording will stop.
2716 CONFIG_BOOTSTAGE_REPORT
2717 Define this to print a report before boot, similar to this:
2719 Timer summary in microseconds:
2722 3,575,678 3,575,678 board_init_f start
2723 3,575,695 17 arch_cpu_init A9
2724 3,575,777 82 arch_cpu_init done
2725 3,659,598 83,821 board_init_r start
2726 3,910,375 250,777 main_loop
2727 29,916,167 26,005,792 bootm_start
2728 30,361,327 445,160 start_kernel
2730 CONFIG_CMD_BOOTSTAGE
2731 Add a 'bootstage' command which supports printing a report
2732 and un/stashing of bootstage data.
2734 CONFIG_BOOTSTAGE_FDT
2735 Stash the bootstage information in the FDT. A root 'bootstage'
2736 node is created with each bootstage id as a child. Each child
2737 has a 'name' property and either 'mark' containing the
2738 mark time in microsecond, or 'accum' containing the
2739 accumulated time for that bootstage id in microseconds.
2744 name = "board_init_f";
2753 Code in the Linux kernel can find this in /proc/devicetree.
2755 Legacy uImage format:
2758 1 common/cmd_bootm.c before attempting to boot an image
2759 -1 common/cmd_bootm.c Image header has bad magic number
2760 2 common/cmd_bootm.c Image header has correct magic number
2761 -2 common/cmd_bootm.c Image header has bad checksum
2762 3 common/cmd_bootm.c Image header has correct checksum
2763 -3 common/cmd_bootm.c Image data has bad checksum
2764 4 common/cmd_bootm.c Image data has correct checksum
2765 -4 common/cmd_bootm.c Image is for unsupported architecture
2766 5 common/cmd_bootm.c Architecture check OK
2767 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2768 6 common/cmd_bootm.c Image Type check OK
2769 -6 common/cmd_bootm.c gunzip uncompression error
2770 -7 common/cmd_bootm.c Unimplemented compression type
2771 7 common/cmd_bootm.c Uncompression OK
2772 8 common/cmd_bootm.c No uncompress/copy overwrite error
2773 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2775 9 common/image.c Start initial ramdisk verification
2776 -10 common/image.c Ramdisk header has bad magic number
2777 -11 common/image.c Ramdisk header has bad checksum
2778 10 common/image.c Ramdisk header is OK
2779 -12 common/image.c Ramdisk data has bad checksum
2780 11 common/image.c Ramdisk data has correct checksum
2781 12 common/image.c Ramdisk verification complete, start loading
2782 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2783 13 common/image.c Start multifile image verification
2784 14 common/image.c No initial ramdisk, no multifile, continue.
2786 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2788 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2789 -31 post/post.c POST test failed, detected by post_output_backlog()
2790 -32 post/post.c POST test failed, detected by post_run_single()
2792 34 common/cmd_doc.c before loading a Image from a DOC device
2793 -35 common/cmd_doc.c Bad usage of "doc" command
2794 35 common/cmd_doc.c correct usage of "doc" command
2795 -36 common/cmd_doc.c No boot device
2796 36 common/cmd_doc.c correct boot device
2797 -37 common/cmd_doc.c Unknown Chip ID on boot device
2798 37 common/cmd_doc.c correct chip ID found, device available
2799 -38 common/cmd_doc.c Read Error on boot device
2800 38 common/cmd_doc.c reading Image header from DOC device OK
2801 -39 common/cmd_doc.c Image header has bad magic number
2802 39 common/cmd_doc.c Image header has correct magic number
2803 -40 common/cmd_doc.c Error reading Image from DOC device
2804 40 common/cmd_doc.c Image header has correct magic number
2805 41 common/cmd_ide.c before loading a Image from a IDE device
2806 -42 common/cmd_ide.c Bad usage of "ide" command
2807 42 common/cmd_ide.c correct usage of "ide" command
2808 -43 common/cmd_ide.c No boot device
2809 43 common/cmd_ide.c boot device found
2810 -44 common/cmd_ide.c Device not available
2811 44 common/cmd_ide.c Device available
2812 -45 common/cmd_ide.c wrong partition selected
2813 45 common/cmd_ide.c partition selected
2814 -46 common/cmd_ide.c Unknown partition table
2815 46 common/cmd_ide.c valid partition table found
2816 -47 common/cmd_ide.c Invalid partition type
2817 47 common/cmd_ide.c correct partition type
2818 -48 common/cmd_ide.c Error reading Image Header on boot device
2819 48 common/cmd_ide.c reading Image Header from IDE device OK
2820 -49 common/cmd_ide.c Image header has bad magic number
2821 49 common/cmd_ide.c Image header has correct magic number
2822 -50 common/cmd_ide.c Image header has bad checksum
2823 50 common/cmd_ide.c Image header has correct checksum
2824 -51 common/cmd_ide.c Error reading Image from IDE device
2825 51 common/cmd_ide.c reading Image from IDE device OK
2826 52 common/cmd_nand.c before loading a Image from a NAND device
2827 -53 common/cmd_nand.c Bad usage of "nand" command
2828 53 common/cmd_nand.c correct usage of "nand" command
2829 -54 common/cmd_nand.c No boot device
2830 54 common/cmd_nand.c boot device found
2831 -55 common/cmd_nand.c Unknown Chip ID on boot device
2832 55 common/cmd_nand.c correct chip ID found, device available
2833 -56 common/cmd_nand.c Error reading Image Header on boot device
2834 56 common/cmd_nand.c reading Image Header from NAND device OK
2835 -57 common/cmd_nand.c Image header has bad magic number
2836 57 common/cmd_nand.c Image header has correct magic number
2837 -58 common/cmd_nand.c Error reading Image from NAND device
2838 58 common/cmd_nand.c reading Image from NAND device OK
2840 -60 common/env_common.c Environment has a bad CRC, using default
2842 64 net/eth.c starting with Ethernet configuration.
2843 -64 net/eth.c no Ethernet found.
2844 65 net/eth.c Ethernet found.
2846 -80 common/cmd_net.c usage wrong
2847 80 common/cmd_net.c before calling NetLoop()
2848 -81 common/cmd_net.c some error in NetLoop() occurred
2849 81 common/cmd_net.c NetLoop() back without error
2850 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2851 82 common/cmd_net.c trying automatic boot
2852 83 common/cmd_net.c running "source" command
2853 -83 common/cmd_net.c some error in automatic boot or "source" command
2854 84 common/cmd_net.c end without errors
2859 100 common/cmd_bootm.c Kernel FIT Image has correct format
2860 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2861 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2862 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2863 102 common/cmd_bootm.c Kernel unit name specified
2864 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2865 103 common/cmd_bootm.c Found configuration node
2866 104 common/cmd_bootm.c Got kernel subimage node offset
2867 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2868 105 common/cmd_bootm.c Kernel subimage hash verification OK
2869 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2870 106 common/cmd_bootm.c Architecture check OK
2871 -106 common/cmd_bootm.c Kernel subimage has wrong type
2872 107 common/cmd_bootm.c Kernel subimage type OK
2873 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2874 108 common/cmd_bootm.c Got kernel subimage data/size
2875 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2876 -109 common/cmd_bootm.c Can't get kernel subimage type
2877 -110 common/cmd_bootm.c Can't get kernel subimage comp
2878 -111 common/cmd_bootm.c Can't get kernel subimage os
2879 -112 common/cmd_bootm.c Can't get kernel subimage load address
2880 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2882 120 common/image.c Start initial ramdisk verification
2883 -120 common/image.c Ramdisk FIT image has incorrect format
2884 121 common/image.c Ramdisk FIT image has correct format
2885 122 common/image.c No ramdisk subimage unit name, using configuration
2886 -122 common/image.c Can't get configuration for ramdisk subimage
2887 123 common/image.c Ramdisk unit name specified
2888 -124 common/image.c Can't get ramdisk subimage node offset
2889 125 common/image.c Got ramdisk subimage node offset
2890 -125 common/image.c Ramdisk subimage hash verification failed
2891 126 common/image.c Ramdisk subimage hash verification OK
2892 -126 common/image.c Ramdisk subimage for unsupported architecture
2893 127 common/image.c Architecture check OK
2894 -127 common/image.c Can't get ramdisk subimage data/size
2895 128 common/image.c Got ramdisk subimage data/size
2896 129 common/image.c Can't get ramdisk load address
2897 -129 common/image.c Got ramdisk load address
2899 -130 common/cmd_doc.c Incorrect FIT image format
2900 131 common/cmd_doc.c FIT image format OK
2902 -140 common/cmd_ide.c Incorrect FIT image format
2903 141 common/cmd_ide.c FIT image format OK
2905 -150 common/cmd_nand.c Incorrect FIT image format
2906 151 common/cmd_nand.c FIT image format OK
2908 - FIT image support:
2910 Enable support for the FIT uImage format.
2912 CONFIG_FIT_BEST_MATCH
2913 When no configuration is explicitly selected, default to the
2914 one whose fdt's compatibility field best matches that of
2915 U-Boot itself. A match is considered "best" if it matches the
2916 most specific compatibility entry of U-Boot's fdt's root node.
2917 The order of entries in the configuration's fdt is ignored.
2919 CONFIG_FIT_SIGNATURE
2920 This option enables signature verification of FIT uImages,
2921 using a hash signed and verified using RSA. See
2922 doc/uImage.FIT/signature.txt for more details.
2924 - Standalone program support:
2925 CONFIG_STANDALONE_LOAD_ADDR
2927 This option defines a board specific value for the
2928 address where standalone program gets loaded, thus
2929 overwriting the architecture dependent default
2932 - Frame Buffer Address:
2935 Define CONFIG_FB_ADDR if you want to use specific
2936 address for frame buffer. This is typically the case
2937 when using a graphics controller has separate video
2938 memory. U-Boot will then place the frame buffer at
2939 the given address instead of dynamically reserving it
2940 in system RAM by calling lcd_setmem(), which grabs
2941 the memory for the frame buffer depending on the
2942 configured panel size.
2944 Please see board_init_f function.
2946 - Automatic software updates via TFTP server
2948 CONFIG_UPDATE_TFTP_CNT_MAX
2949 CONFIG_UPDATE_TFTP_MSEC_MAX
2951 These options enable and control the auto-update feature;
2952 for a more detailed description refer to doc/README.update.
2954 - MTD Support (mtdparts command, UBI support)
2957 Adds the MTD device infrastructure from the Linux kernel.
2958 Needed for mtdparts command support.
2960 CONFIG_MTD_PARTITIONS
2962 Adds the MTD partitioning infrastructure from the Linux
2963 kernel. Needed for UBI support.
2968 Adds commands for interacting with MTD partitions formatted
2969 with the UBI flash translation layer
2971 Requires also defining CONFIG_RBTREE
2973 CONFIG_UBI_SILENCE_MSG
2975 Make the verbose messages from UBI stop printing. This leaves
2976 warnings and errors enabled.
2981 Adds commands for interacting with UBI volumes formatted as
2982 UBIFS. UBIFS is read-only in u-boot.
2984 Requires UBI support as well as CONFIG_LZO
2986 CONFIG_UBIFS_SILENCE_MSG
2988 Make the verbose messages from UBIFS stop printing. This leaves
2989 warnings and errors enabled.
2993 Enable building of SPL globally.
2996 LDSCRIPT for linking the SPL binary.
2998 CONFIG_SPL_MAX_FOOTPRINT
2999 Maximum size in memory allocated to the SPL, BSS included.
3000 When defined, the linker checks that the actual memory
3001 used by SPL from _start to __bss_end does not exceed it.
3002 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3003 must not be both defined at the same time.
3006 Maximum size of the SPL image (text, data, rodata, and
3007 linker lists sections), BSS excluded.
3008 When defined, the linker checks that the actual size does
3011 CONFIG_SPL_TEXT_BASE
3012 TEXT_BASE for linking the SPL binary.
3014 CONFIG_SPL_RELOC_TEXT_BASE
3015 Address to relocate to. If unspecified, this is equal to
3016 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3018 CONFIG_SPL_BSS_START_ADDR
3019 Link address for the BSS within the SPL binary.
3021 CONFIG_SPL_BSS_MAX_SIZE
3022 Maximum size in memory allocated to the SPL BSS.
3023 When defined, the linker checks that the actual memory used
3024 by SPL from __bss_start to __bss_end does not exceed it.
3025 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3026 must not be both defined at the same time.
3029 Adress of the start of the stack SPL will use
3031 CONFIG_SPL_RELOC_STACK
3032 Adress of the start of the stack SPL will use after
3033 relocation. If unspecified, this is equal to
3036 CONFIG_SYS_SPL_MALLOC_START
3037 Starting address of the malloc pool used in SPL.
3039 CONFIG_SYS_SPL_MALLOC_SIZE
3040 The size of the malloc pool used in SPL.
3042 CONFIG_SPL_FRAMEWORK
3043 Enable the SPL framework under common/. This framework
3044 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3045 NAND loading of the Linux Kernel.
3047 CONFIG_SPL_DISPLAY_PRINT
3048 For ARM, enable an optional function to print more information
3049 about the running system.
3051 CONFIG_SPL_INIT_MINIMAL
3052 Arch init code should be built for a very small image
3054 CONFIG_SPL_LIBCOMMON_SUPPORT
3055 Support for common/libcommon.o in SPL binary
3057 CONFIG_SPL_LIBDISK_SUPPORT
3058 Support for disk/libdisk.o in SPL binary
3060 CONFIG_SPL_I2C_SUPPORT
3061 Support for drivers/i2c/libi2c.o in SPL binary
3063 CONFIG_SPL_GPIO_SUPPORT
3064 Support for drivers/gpio/libgpio.o in SPL binary
3066 CONFIG_SPL_MMC_SUPPORT
3067 Support for drivers/mmc/libmmc.o in SPL binary
3069 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3070 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3071 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3072 Address, size and partition on the MMC to load U-Boot from
3073 when the MMC is being used in raw mode.
3075 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3076 Sector to load kernel uImage from when MMC is being
3077 used in raw mode (for Falcon mode)
3079 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3080 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3081 Sector and number of sectors to load kernel argument
3082 parameters from when MMC is being used in raw mode
3085 CONFIG_SPL_FAT_SUPPORT
3086 Support for fs/fat/libfat.o in SPL binary
3088 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3089 Filename to read to load U-Boot when reading from FAT
3091 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3092 Filename to read to load kernel uImage when reading
3093 from FAT (for Falcon mode)
3095 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3096 Filename to read to load kernel argument parameters
3097 when reading from FAT (for Falcon mode)
3099 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3100 Set this for NAND SPL on PPC mpc83xx targets, so that
3101 start.S waits for the rest of the SPL to load before
3102 continuing (the hardware starts execution after just
3103 loading the first page rather than the full 4K).
3105 CONFIG_SPL_NAND_BASE
3106 Include nand_base.c in the SPL. Requires
3107 CONFIG_SPL_NAND_DRIVERS.
3109 CONFIG_SPL_NAND_DRIVERS
3110 SPL uses normal NAND drivers, not minimal drivers.
3113 Include standard software ECC in the SPL
3115 CONFIG_SPL_NAND_SIMPLE
3116 Support for NAND boot using simple NAND drivers that
3117 expose the cmd_ctrl() interface.
3119 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3120 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3121 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3122 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3123 CONFIG_SYS_NAND_ECCBYTES
3124 Defines the size and behavior of the NAND that SPL uses
3127 CONFIG_SYS_NAND_U_BOOT_OFFS
3128 Location in NAND to read U-Boot from
3130 CONFIG_SYS_NAND_U_BOOT_DST
3131 Location in memory to load U-Boot to
3133 CONFIG_SYS_NAND_U_BOOT_SIZE
3134 Size of image to load
3136 CONFIG_SYS_NAND_U_BOOT_START
3137 Entry point in loaded image to jump to
3139 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3140 Define this if you need to first read the OOB and then the
3141 data. This is used for example on davinci plattforms.
3143 CONFIG_SPL_OMAP3_ID_NAND
3144 Support for an OMAP3-specific set of functions to return the
3145 ID and MFR of the first attached NAND chip, if present.
3147 CONFIG_SPL_SERIAL_SUPPORT
3148 Support for drivers/serial/libserial.o in SPL binary
3150 CONFIG_SPL_SPI_FLASH_SUPPORT
3151 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3153 CONFIG_SPL_SPI_SUPPORT
3154 Support for drivers/spi/libspi.o in SPL binary
3156 CONFIG_SPL_RAM_DEVICE
3157 Support for running image already present in ram, in SPL binary
3159 CONFIG_SPL_LIBGENERIC_SUPPORT
3160 Support for lib/libgeneric.o in SPL binary
3162 CONFIG_SPL_ENV_SUPPORT
3163 Support for the environment operating in SPL binary
3165 CONFIG_SPL_NET_SUPPORT
3166 Support for the net/libnet.o in SPL binary.
3167 It conflicts with SPL env from storage medium specified by
3168 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3171 Image offset to which the SPL should be padded before appending
3172 the SPL payload. By default, this is defined as
3173 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3174 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3175 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3178 Final target image containing SPL and payload. Some SPLs
3179 use an arch-specific makefile fragment instead, for
3180 example if more than one image needs to be produced.
3182 CONFIG_FIT_SPL_PRINT
3183 Printing information about a FIT image adds quite a bit of
3184 code to SPL. So this is normally disabled in SPL. Use this
3185 option to re-enable it. This will affect the output of the
3186 bootm command when booting a FIT image.
3191 [so far only for SMDK2400 boards]
3193 - Modem support enable:
3194 CONFIG_MODEM_SUPPORT
3196 - RTS/CTS Flow control enable:
3199 - Modem debug support:
3200 CONFIG_MODEM_SUPPORT_DEBUG
3202 Enables debugging stuff (char screen[1024], dbg())
3203 for modem support. Useful only with BDI2000.
3205 - Interrupt support (PPC):
3207 There are common interrupt_init() and timer_interrupt()
3208 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3209 for CPU specific initialization. interrupt_init_cpu()
3210 should set decrementer_count to appropriate value. If
3211 CPU resets decrementer automatically after interrupt
3212 (ppc4xx) it should set decrementer_count to zero.
3213 timer_interrupt() calls timer_interrupt_cpu() for CPU
3214 specific handling. If board has watchdog / status_led
3215 / other_activity_monitor it works automatically from
3216 general timer_interrupt().
3220 In the target system modem support is enabled when a
3221 specific key (key combination) is pressed during
3222 power-on. Otherwise U-Boot will boot normally
3223 (autoboot). The key_pressed() function is called from
3224 board_init(). Currently key_pressed() is a dummy
3225 function, returning 1 and thus enabling modem
3228 If there are no modem init strings in the
3229 environment, U-Boot proceed to autoboot; the
3230 previous output (banner, info printfs) will be
3233 See also: doc/README.Modem
3235 Board initialization settings:
3236 ------------------------------
3238 During Initialization u-boot calls a number of board specific functions
3239 to allow the preparation of board specific prerequisites, e.g. pin setup
3240 before drivers are initialized. To enable these callbacks the
3241 following configuration macros have to be defined. Currently this is
3242 architecture specific, so please check arch/your_architecture/lib/board.c
3243 typically in board_init_f() and board_init_r().
3245 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3246 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3247 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3248 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3250 Configuration Settings:
3251 -----------------------
3253 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3254 undefine this when you're short of memory.
3256 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3257 width of the commands listed in the 'help' command output.
3259 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3260 prompt for user input.
3262 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3264 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3266 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3268 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3269 the application (usually a Linux kernel) when it is
3272 - CONFIG_SYS_BAUDRATE_TABLE:
3273 List of legal baudrate settings for this board.
3275 - CONFIG_SYS_CONSOLE_INFO_QUIET
3276 Suppress display of console information at boot.
3278 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3279 If the board specific function
3280 extern int overwrite_console (void);
3281 returns 1, the stdin, stderr and stdout are switched to the
3282 serial port, else the settings in the environment are used.
3284 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3285 Enable the call to overwrite_console().
3287 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3288 Enable overwrite of previous console environment settings.
3290 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3291 Begin and End addresses of the area used by the
3294 - CONFIG_SYS_ALT_MEMTEST:
3295 Enable an alternate, more extensive memory test.
3297 - CONFIG_SYS_MEMTEST_SCRATCH:
3298 Scratch address used by the alternate memory test
3299 You only need to set this if address zero isn't writeable
3301 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3302 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3303 this specified memory area will get subtracted from the top
3304 (end) of RAM and won't get "touched" at all by U-Boot. By
3305 fixing up gd->ram_size the Linux kernel should gets passed
3306 the now "corrected" memory size and won't touch it either.
3307 This should work for arch/ppc and arch/powerpc. Only Linux
3308 board ports in arch/powerpc with bootwrapper support that
3309 recalculate the memory size from the SDRAM controller setup
3310 will have to get fixed in Linux additionally.
3312 This option can be used as a workaround for the 440EPx/GRx
3313 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3316 WARNING: Please make sure that this value is a multiple of
3317 the Linux page size (normally 4k). If this is not the case,
3318 then the end address of the Linux memory will be located at a
3319 non page size aligned address and this could cause major
3322 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3323 Enable temporary baudrate change while serial download
3325 - CONFIG_SYS_SDRAM_BASE:
3326 Physical start address of SDRAM. _Must_ be 0 here.
3328 - CONFIG_SYS_MBIO_BASE:
3329 Physical start address of Motherboard I/O (if using a
3332 - CONFIG_SYS_FLASH_BASE:
3333 Physical start address of Flash memory.
3335 - CONFIG_SYS_MONITOR_BASE:
3336 Physical start address of boot monitor code (set by
3337 make config files to be same as the text base address
3338 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3339 CONFIG_SYS_FLASH_BASE when booting from flash.
3341 - CONFIG_SYS_MONITOR_LEN:
3342 Size of memory reserved for monitor code, used to
3343 determine _at_compile_time_ (!) if the environment is
3344 embedded within the U-Boot image, or in a separate
3347 - CONFIG_SYS_MALLOC_LEN:
3348 Size of DRAM reserved for malloc() use.
3350 - CONFIG_SYS_BOOTM_LEN:
3351 Normally compressed uImages are limited to an
3352 uncompressed size of 8 MBytes. If this is not enough,
3353 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3354 to adjust this setting to your needs.
3356 - CONFIG_SYS_BOOTMAPSZ:
3357 Maximum size of memory mapped by the startup code of
3358 the Linux kernel; all data that must be processed by
3359 the Linux kernel (bd_info, boot arguments, FDT blob if
3360 used) must be put below this limit, unless "bootm_low"
3361 enviroment variable is defined and non-zero. In such case
3362 all data for the Linux kernel must be between "bootm_low"
3363 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3364 variable "bootm_mapsize" will override the value of
3365 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3366 then the value in "bootm_size" will be used instead.
3368 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3369 Enable initrd_high functionality. If defined then the
3370 initrd_high feature is enabled and the bootm ramdisk subcommand
3373 - CONFIG_SYS_BOOT_GET_CMDLINE:
3374 Enables allocating and saving kernel cmdline in space between
3375 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3377 - CONFIG_SYS_BOOT_GET_KBD:
3378 Enables allocating and saving a kernel copy of the bd_info in
3379 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3381 - CONFIG_SYS_MAX_FLASH_BANKS:
3382 Max number of Flash memory banks
3384 - CONFIG_SYS_MAX_FLASH_SECT:
3385 Max number of sectors on a Flash chip
3387 - CONFIG_SYS_FLASH_ERASE_TOUT:
3388 Timeout for Flash erase operations (in ms)
3390 - CONFIG_SYS_FLASH_WRITE_TOUT:
3391 Timeout for Flash write operations (in ms)
3393 - CONFIG_SYS_FLASH_LOCK_TOUT
3394 Timeout for Flash set sector lock bit operation (in ms)
3396 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3397 Timeout for Flash clear lock bits operation (in ms)
3399 - CONFIG_SYS_FLASH_PROTECTION
3400 If defined, hardware flash sectors protection is used
3401 instead of U-Boot software protection.
3403 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3405 Enable TFTP transfers directly to flash memory;
3406 without this option such a download has to be
3407 performed in two steps: (1) download to RAM, and (2)
3408 copy from RAM to flash.
3410 The two-step approach is usually more reliable, since
3411 you can check if the download worked before you erase
3412 the flash, but in some situations (when system RAM is
3413 too limited to allow for a temporary copy of the
3414 downloaded image) this option may be very useful.
3416 - CONFIG_SYS_FLASH_CFI:
3417 Define if the flash driver uses extra elements in the
3418 common flash structure for storing flash geometry.
3420 - CONFIG_FLASH_CFI_DRIVER
3421 This option also enables the building of the cfi_flash driver
3422 in the drivers directory
3424 - CONFIG_FLASH_CFI_MTD
3425 This option enables the building of the cfi_mtd driver
3426 in the drivers directory. The driver exports CFI flash
3429 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3430 Use buffered writes to flash.
3432 - CONFIG_FLASH_SPANSION_S29WS_N
3433 s29ws-n MirrorBit flash has non-standard addresses for buffered
3436 - CONFIG_SYS_FLASH_QUIET_TEST
3437 If this option is defined, the common CFI flash doesn't
3438 print it's warning upon not recognized FLASH banks. This
3439 is useful, if some of the configured banks are only
3440 optionally available.
3442 - CONFIG_FLASH_SHOW_PROGRESS
3443 If defined (must be an integer), print out countdown
3444 digits and dots. Recommended value: 45 (9..1) for 80
3445 column displays, 15 (3..1) for 40 column displays.
3447 - CONFIG_FLASH_VERIFY
3448 If defined, the content of the flash (destination) is compared
3449 against the source after the write operation. An error message
3450 will be printed when the contents are not identical.
3451 Please note that this option is useless in nearly all cases,
3452 since such flash programming errors usually are detected earlier
3453 while unprotecting/erasing/programming. Please only enable
3454 this option if you really know what you are doing.
3456 - CONFIG_SYS_RX_ETH_BUFFER:
3457 Defines the number of Ethernet receive buffers. On some
3458 Ethernet controllers it is recommended to set this value
3459 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3460 buffers can be full shortly after enabling the interface
3461 on high Ethernet traffic.
3462 Defaults to 4 if not defined.
3464 - CONFIG_ENV_MAX_ENTRIES
3466 Maximum number of entries in the hash table that is used
3467 internally to store the environment settings. The default
3468 setting is supposed to be generous and should work in most
3469 cases. This setting can be used to tune behaviour; see
3470 lib/hashtable.c for details.
3472 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3473 - CONFIG_ENV_FLAGS_LIST_STATIC
3474 Enable validation of the values given to enviroment variables when
3475 calling env set. Variables can be restricted to only decimal,
3476 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3477 the variables can also be restricted to IP address or MAC address.
3479 The format of the list is:
3480 type_attribute = [s|d|x|b|i|m]
3481 access_atribute = [a|r|o|c]
3482 attributes = type_attribute[access_atribute]
3483 entry = variable_name[:attributes]
3486 The type attributes are:
3487 s - String (default)
3490 b - Boolean ([1yYtT|0nNfF])
3494 The access attributes are:
3500 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3501 Define this to a list (string) to define the ".flags"
3502 envirnoment variable in the default or embedded environment.
3504 - CONFIG_ENV_FLAGS_LIST_STATIC
3505 Define this to a list (string) to define validation that
3506 should be done if an entry is not found in the ".flags"
3507 environment variable. To override a setting in the static
3508 list, simply add an entry for the same variable name to the
3511 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3512 If defined, don't allow the -f switch to env set override variable
3515 - CONFIG_SYS_GENERIC_BOARD
3516 This selects the architecture-generic board system instead of the
3517 architecture-specific board files. It is intended to move boards
3518 to this new framework over time. Defining this will disable the
3519 arch/foo/lib/board.c file and use common/board_f.c and
3520 common/board_r.c instead. To use this option your architecture
3521 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3522 its config.mk file). If you find problems enabling this option on
3523 your board please report the problem and send patches!
3525 - CONFIG_SYS_SYM_OFFSETS
3526 This is set by architectures that use offsets for link symbols
3527 instead of absolute values. So bss_start is obtained using an
3528 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3529 directly. You should not need to touch this setting.
3531 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3532 This is set by OMAP boards for the max time that reset should
3533 be asserted. See doc/README.omap-reset-time for details on how
3534 the value can be calulated on a given board.
3536 The following definitions that deal with the placement and management
3537 of environment data (variable area); in general, we support the
3538 following configurations:
3540 - CONFIG_BUILD_ENVCRC:
3542 Builds up envcrc with the target environment so that external utils
3543 may easily extract it and embed it in final U-Boot images.
3545 - CONFIG_ENV_IS_IN_FLASH:
3547 Define this if the environment is in flash memory.
3549 a) The environment occupies one whole flash sector, which is
3550 "embedded" in the text segment with the U-Boot code. This
3551 happens usually with "bottom boot sector" or "top boot
3552 sector" type flash chips, which have several smaller
3553 sectors at the start or the end. For instance, such a
3554 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3555 such a case you would place the environment in one of the
3556 4 kB sectors - with U-Boot code before and after it. With
3557 "top boot sector" type flash chips, you would put the
3558 environment in one of the last sectors, leaving a gap
3559 between U-Boot and the environment.
3561 - CONFIG_ENV_OFFSET:
3563 Offset of environment data (variable area) to the
3564 beginning of flash memory; for instance, with bottom boot
3565 type flash chips the second sector can be used: the offset
3566 for this sector is given here.
3568 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3572 This is just another way to specify the start address of
3573 the flash sector containing the environment (instead of
3576 - CONFIG_ENV_SECT_SIZE:
3578 Size of the sector containing the environment.
3581 b) Sometimes flash chips have few, equal sized, BIG sectors.
3582 In such a case you don't want to spend a whole sector for
3587 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3588 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3589 of this flash sector for the environment. This saves
3590 memory for the RAM copy of the environment.
3592 It may also save flash memory if you decide to use this
3593 when your environment is "embedded" within U-Boot code,
3594 since then the remainder of the flash sector could be used
3595 for U-Boot code. It should be pointed out that this is
3596 STRONGLY DISCOURAGED from a robustness point of view:
3597 updating the environment in flash makes it always
3598 necessary to erase the WHOLE sector. If something goes
3599 wrong before the contents has been restored from a copy in
3600 RAM, your target system will be dead.
3602 - CONFIG_ENV_ADDR_REDUND
3603 CONFIG_ENV_SIZE_REDUND
3605 These settings describe a second storage area used to hold
3606 a redundant copy of the environment data, so that there is
3607 a valid backup copy in case there is a power failure during
3608 a "saveenv" operation.
3610 BE CAREFUL! Any changes to the flash layout, and some changes to the
3611 source code will make it necessary to adapt <board>/u-boot.lds*
3615 - CONFIG_ENV_IS_IN_NVRAM:
3617 Define this if you have some non-volatile memory device
3618 (NVRAM, battery buffered SRAM) which you want to use for the
3624 These two #defines are used to determine the memory area you
3625 want to use for environment. It is assumed that this memory
3626 can just be read and written to, without any special
3629 BE CAREFUL! The first access to the environment happens quite early
3630 in U-Boot initalization (when we try to get the setting of for the
3631 console baudrate). You *MUST* have mapped your NVRAM area then, or
3634 Please note that even with NVRAM we still use a copy of the
3635 environment in RAM: we could work on NVRAM directly, but we want to
3636 keep settings there always unmodified except somebody uses "saveenv"
3637 to save the current settings.
3640 - CONFIG_ENV_IS_IN_EEPROM:
3642 Use this if you have an EEPROM or similar serial access
3643 device and a driver for it.
3645 - CONFIG_ENV_OFFSET:
3648 These two #defines specify the offset and size of the
3649 environment area within the total memory of your EEPROM.
3651 - CONFIG_SYS_I2C_EEPROM_ADDR:
3652 If defined, specified the chip address of the EEPROM device.
3653 The default address is zero.
3655 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3656 If defined, the number of bits used to address bytes in a
3657 single page in the EEPROM device. A 64 byte page, for example
3658 would require six bits.
3660 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3661 If defined, the number of milliseconds to delay between
3662 page writes. The default is zero milliseconds.
3664 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3665 The length in bytes of the EEPROM memory array address. Note
3666 that this is NOT the chip address length!
3668 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3669 EEPROM chips that implement "address overflow" are ones
3670 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3671 address and the extra bits end up in the "chip address" bit
3672 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3675 Note that we consider the length of the address field to
3676 still be one byte because the extra address bits are hidden
3677 in the chip address.
3679 - CONFIG_SYS_EEPROM_SIZE:
3680 The size in bytes of the EEPROM device.
3682 - CONFIG_ENV_EEPROM_IS_ON_I2C
3683 define this, if you have I2C and SPI activated, and your
3684 EEPROM, which holds the environment, is on the I2C bus.
3686 - CONFIG_I2C_ENV_EEPROM_BUS
3687 if you have an Environment on an EEPROM reached over
3688 I2C muxes, you can define here, how to reach this
3689 EEPROM. For example:
3691 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3693 EEPROM which holds the environment, is reached over
3694 a pca9547 i2c mux with address 0x70, channel 3.
3696 - CONFIG_ENV_IS_IN_DATAFLASH:
3698 Define this if you have a DataFlash memory device which you
3699 want to use for the environment.
3701 - CONFIG_ENV_OFFSET:
3705 These three #defines specify the offset and size of the
3706 environment area within the total memory of your DataFlash placed
3707 at the specified address.
3709 - CONFIG_ENV_IS_IN_REMOTE:
3711 Define this if you have a remote memory space which you
3712 want to use for the local device's environment.
3717 These two #defines specify the address and size of the
3718 environment area within the remote memory space. The
3719 local device can get the environment from remote memory
3720 space by SRIO or PCIE links.
3722 BE CAREFUL! For some special cases, the local device can not use
3723 "saveenv" command. For example, the local device will get the
3724 environment stored in a remote NOR flash by SRIO or PCIE link,
3725 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3727 - CONFIG_ENV_IS_IN_NAND:
3729 Define this if you have a NAND device which you want to use
3730 for the environment.
3732 - CONFIG_ENV_OFFSET:
3735 These two #defines specify the offset and size of the environment
3736 area within the first NAND device. CONFIG_ENV_OFFSET must be
3737 aligned to an erase block boundary.
3739 - CONFIG_ENV_OFFSET_REDUND (optional):
3741 This setting describes a second storage area of CONFIG_ENV_SIZE
3742 size used to hold a redundant copy of the environment data, so
3743 that there is a valid backup copy in case there is a power failure
3744 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3745 aligned to an erase block boundary.
3747 - CONFIG_ENV_RANGE (optional):
3749 Specifies the length of the region in which the environment
3750 can be written. This should be a multiple of the NAND device's
3751 block size. Specifying a range with more erase blocks than
3752 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3753 the range to be avoided.
3755 - CONFIG_ENV_OFFSET_OOB (optional):
3757 Enables support for dynamically retrieving the offset of the
3758 environment from block zero's out-of-band data. The
3759 "nand env.oob" command can be used to record this offset.
3760 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3761 using CONFIG_ENV_OFFSET_OOB.
3763 - CONFIG_NAND_ENV_DST
3765 Defines address in RAM to which the nand_spl code should copy the
3766 environment. If redundant environment is used, it will be copied to
3767 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3769 - CONFIG_ENV_IS_IN_UBI:
3771 Define this if you have an UBI volume that you want to use for the
3772 environment. This has the benefit of wear-leveling the environment
3773 accesses, which is important on NAND.
3775 - CONFIG_ENV_UBI_PART:
3777 Define this to a string that is the mtd partition containing the UBI.
3779 - CONFIG_ENV_UBI_VOLUME:
3781 Define this to the name of the volume that you want to store the
3784 - CONFIG_ENV_UBI_VOLUME_REDUND:
3786 Define this to the name of another volume to store a second copy of
3787 the environment in. This will enable redundant environments in UBI.
3788 It is assumed that both volumes are in the same MTD partition.
3790 - CONFIG_UBI_SILENCE_MSG
3791 - CONFIG_UBIFS_SILENCE_MSG
3793 You will probably want to define these to avoid a really noisy system
3794 when storing the env in UBI.
3796 - CONFIG_ENV_IS_IN_MMC:
3798 Define this if you have an MMC device which you want to use for the
3801 - CONFIG_SYS_MMC_ENV_DEV:
3803 Specifies which MMC device the environment is stored in.
3805 - CONFIG_SYS_MMC_ENV_PART (optional):
3807 Specifies which MMC partition the environment is stored in. If not
3808 set, defaults to partition 0, the user area. Common values might be
3809 1 (first MMC boot partition), 2 (second MMC boot partition).
3811 - CONFIG_ENV_OFFSET:
3814 These two #defines specify the offset and size of the environment
3815 area within the specified MMC device.
3817 If offset is positive (the usual case), it is treated as relative to
3818 the start of the MMC partition. If offset is negative, it is treated
3819 as relative to the end of the MMC partition. This can be useful if
3820 your board may be fitted with different MMC devices, which have
3821 different sizes for the MMC partitions, and you always want the
3822 environment placed at the very end of the partition, to leave the
3823 maximum possible space before it, to store other data.
3825 These two values are in units of bytes, but must be aligned to an
3826 MMC sector boundary.
3828 - CONFIG_ENV_OFFSET_REDUND (optional):
3830 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3831 hold a redundant copy of the environment data. This provides a
3832 valid backup copy in case the other copy is corrupted, e.g. due
3833 to a power failure during a "saveenv" operation.
3835 This value may also be positive or negative; this is handled in the
3836 same way as CONFIG_ENV_OFFSET.
3838 This value is also in units of bytes, but must also be aligned to
3839 an MMC sector boundary.
3841 - CONFIG_ENV_SIZE_REDUND (optional):
3843 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3844 set. If this value is set, it must be set to the same value as
3847 - CONFIG_SYS_SPI_INIT_OFFSET
3849 Defines offset to the initial SPI buffer area in DPRAM. The
3850 area is used at an early stage (ROM part) if the environment
3851 is configured to reside in the SPI EEPROM: We need a 520 byte
3852 scratch DPRAM area. It is used between the two initialization
3853 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3854 to be a good choice since it makes it far enough from the
3855 start of the data area as well as from the stack pointer.
3857 Please note that the environment is read-only until the monitor
3858 has been relocated to RAM and a RAM copy of the environment has been
3859 created; also, when using EEPROM you will have to use getenv_f()
3860 until then to read environment variables.
3862 The environment is protected by a CRC32 checksum. Before the monitor
3863 is relocated into RAM, as a result of a bad CRC you will be working
3864 with the compiled-in default environment - *silently*!!! [This is
3865 necessary, because the first environment variable we need is the
3866 "baudrate" setting for the console - if we have a bad CRC, we don't
3867 have any device yet where we could complain.]
3869 Note: once the monitor has been relocated, then it will complain if
3870 the default environment is used; a new CRC is computed as soon as you
3871 use the "saveenv" command to store a valid environment.
3873 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3874 Echo the inverted Ethernet link state to the fault LED.
3876 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3877 also needs to be defined.
3879 - CONFIG_SYS_FAULT_MII_ADDR:
3880 MII address of the PHY to check for the Ethernet link state.
3882 - CONFIG_NS16550_MIN_FUNCTIONS:
3883 Define this if you desire to only have use of the NS16550_init
3884 and NS16550_putc functions for the serial driver located at
3885 drivers/serial/ns16550.c. This option is useful for saving
3886 space for already greatly restricted images, including but not
3887 limited to NAND_SPL configurations.
3889 - CONFIG_DISPLAY_BOARDINFO
3890 Display information about the board that U-Boot is running on
3891 when U-Boot starts up. The board function checkboard() is called
3894 - CONFIG_DISPLAY_BOARDINFO_LATE
3895 Similar to the previous option, but display this information
3896 later, once stdio is running and output goes to the LCD, if
3899 Low Level (hardware related) configuration options:
3900 ---------------------------------------------------
3902 - CONFIG_SYS_CACHELINE_SIZE:
3903 Cache Line Size of the CPU.
3905 - CONFIG_SYS_DEFAULT_IMMR:
3906 Default address of the IMMR after system reset.
3908 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3909 and RPXsuper) to be able to adjust the position of
3910 the IMMR register after a reset.
3912 - CONFIG_SYS_CCSRBAR_DEFAULT:
3913 Default (power-on reset) physical address of CCSR on Freescale
3916 - CONFIG_SYS_CCSRBAR:
3917 Virtual address of CCSR. On a 32-bit build, this is typically
3918 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3920 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3921 for cross-platform code that uses that macro instead.
3923 - CONFIG_SYS_CCSRBAR_PHYS:
3924 Physical address of CCSR. CCSR can be relocated to a new
3925 physical address, if desired. In this case, this macro should
3926 be set to that address. Otherwise, it should be set to the
3927 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3928 is typically relocated on 36-bit builds. It is recommended
3929 that this macro be defined via the _HIGH and _LOW macros:
3931 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3932 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3934 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3935 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3936 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3937 used in assembly code, so it must not contain typecasts or
3938 integer size suffixes (e.g. "ULL").
3940 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3941 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3942 used in assembly code, so it must not contain typecasts or
3943 integer size suffixes (e.g. "ULL").
3945 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3946 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3947 forced to a value that ensures that CCSR is not relocated.
3949 - Floppy Disk Support:
3950 CONFIG_SYS_FDC_DRIVE_NUMBER
3952 the default drive number (default value 0)
3954 CONFIG_SYS_ISA_IO_STRIDE
3956 defines the spacing between FDC chipset registers
3959 CONFIG_SYS_ISA_IO_OFFSET
3961 defines the offset of register from address. It
3962 depends on which part of the data bus is connected to
3963 the FDC chipset. (default value 0)
3965 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3966 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3969 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3970 fdc_hw_init() is called at the beginning of the FDC
3971 setup. fdc_hw_init() must be provided by the board
3972 source code. It is used to make hardware dependant
3976 Most IDE controllers were designed to be connected with PCI
3977 interface. Only few of them were designed for AHB interface.
3978 When software is doing ATA command and data transfer to
3979 IDE devices through IDE-AHB controller, some additional
3980 registers accessing to these kind of IDE-AHB controller
3983 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3984 DO NOT CHANGE unless you know exactly what you're
3985 doing! (11-4) [MPC8xx/82xx systems only]
3987 - CONFIG_SYS_INIT_RAM_ADDR:
3989 Start address of memory area that can be used for
3990 initial data and stack; please note that this must be
3991 writable memory that is working WITHOUT special
3992 initialization, i. e. you CANNOT use normal RAM which
3993 will become available only after programming the
3994 memory controller and running certain initialization
3997 U-Boot uses the following memory types:
3998 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3999 - MPC824X: data cache
4000 - PPC4xx: data cache
4002 - CONFIG_SYS_GBL_DATA_OFFSET:
4004 Offset of the initial data structure in the memory
4005 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4006 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4007 data is located at the end of the available space
4008 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4009 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4010 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4011 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4014 On the MPC824X (or other systems that use the data
4015 cache for initial memory) the address chosen for
4016 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4017 point to an otherwise UNUSED address space between
4018 the top of RAM and the start of the PCI space.
4020 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4022 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4024 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4026 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4028 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4030 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4032 - CONFIG_SYS_OR_TIMING_SDRAM:
4035 - CONFIG_SYS_MAMR_PTA:
4036 periodic timer for refresh
4038 - CONFIG_SYS_DER: Debug Event Register (37-47)
4040 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4041 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4042 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4043 CONFIG_SYS_BR1_PRELIM:
4044 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4046 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4047 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4048 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4049 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4051 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4052 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4053 Machine Mode Register and Memory Periodic Timer
4054 Prescaler definitions (SDRAM timing)
4056 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4057 enable I2C microcode relocation patch (MPC8xx);
4058 define relocation offset in DPRAM [DSP2]
4060 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4061 enable SMC microcode relocation patch (MPC8xx);
4062 define relocation offset in DPRAM [SMC1]
4064 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4065 enable SPI microcode relocation patch (MPC8xx);
4066 define relocation offset in DPRAM [SCC4]
4068 - CONFIG_SYS_USE_OSCCLK:
4069 Use OSCM clock mode on MBX8xx board. Be careful,
4070 wrong setting might damage your board. Read
4071 doc/README.MBX before setting this variable!
4073 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4074 Offset of the bootmode word in DPRAM used by post
4075 (Power On Self Tests). This definition overrides
4076 #define'd default value in commproc.h resp.
4079 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4080 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4081 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4082 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4083 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4084 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4085 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4086 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4087 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4089 - CONFIG_PCI_DISABLE_PCIE:
4090 Disable PCI-Express on systems where it is supported but not
4093 - CONFIG_PCI_ENUM_ONLY
4094 Only scan through and get the devices on the busses.
4095 Don't do any setup work, presumably because someone or
4096 something has already done it, and we don't need to do it
4097 a second time. Useful for platforms that are pre-booted
4098 by coreboot or similar.
4100 - CONFIG_PCI_INDIRECT_BRIDGE:
4101 Enable support for indirect PCI bridges.
4104 Chip has SRIO or not
4107 Board has SRIO 1 port available
4110 Board has SRIO 2 port available
4112 - CONFIG_SRIO_PCIE_BOOT_MASTER
4113 Board can support master function for Boot from SRIO and PCIE
4115 - CONFIG_SYS_SRIOn_MEM_VIRT:
4116 Virtual Address of SRIO port 'n' memory region
4118 - CONFIG_SYS_SRIOn_MEM_PHYS:
4119 Physical Address of SRIO port 'n' memory region
4121 - CONFIG_SYS_SRIOn_MEM_SIZE:
4122 Size of SRIO port 'n' memory region
4124 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4125 Defined to tell the NAND controller that the NAND chip is using
4127 Not all NAND drivers use this symbol.
4128 Example of drivers that use it:
4129 - drivers/mtd/nand/ndfc.c
4130 - drivers/mtd/nand/mxc_nand.c
4132 - CONFIG_SYS_NDFC_EBC0_CFG
4133 Sets the EBC0_CFG register for the NDFC. If not defined
4134 a default value will be used.
4137 Get DDR timing information from an I2C EEPROM. Common
4138 with pluggable memory modules such as SODIMMs
4141 I2C address of the SPD EEPROM
4143 - CONFIG_SYS_SPD_BUS_NUM
4144 If SPD EEPROM is on an I2C bus other than the first
4145 one, specify here. Note that the value must resolve
4146 to something your driver can deal with.
4148 - CONFIG_SYS_DDR_RAW_TIMING
4149 Get DDR timing information from other than SPD. Common with
4150 soldered DDR chips onboard without SPD. DDR raw timing
4151 parameters are extracted from datasheet and hard-coded into
4152 header files or board specific files.
4154 - CONFIG_FSL_DDR_INTERACTIVE
4155 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4157 - CONFIG_SYS_83XX_DDR_USES_CS0
4158 Only for 83xx systems. If specified, then DDR should
4159 be configured using CS0 and CS1 instead of CS2 and CS3.
4161 - CONFIG_ETHER_ON_FEC[12]
4162 Define to enable FEC[12] on a 8xx series processor.
4164 - CONFIG_FEC[12]_PHY
4165 Define to the hardcoded PHY address which corresponds
4166 to the given FEC; i. e.
4167 #define CONFIG_FEC1_PHY 4
4168 means that the PHY with address 4 is connected to FEC1
4170 When set to -1, means to probe for first available.
4172 - CONFIG_FEC[12]_PHY_NORXERR
4173 The PHY does not have a RXERR line (RMII only).
4174 (so program the FEC to ignore it).
4177 Enable RMII mode for all FECs.
4178 Note that this is a global option, we can't
4179 have one FEC in standard MII mode and another in RMII mode.
4181 - CONFIG_CRC32_VERIFY
4182 Add a verify option to the crc32 command.
4185 => crc32 -v <address> <count> <crc32>
4187 Where address/count indicate a memory area
4188 and crc32 is the correct crc32 which the
4192 Add the "loopw" memory command. This only takes effect if
4193 the memory commands are activated globally (CONFIG_CMD_MEM).
4196 Add the "mdc" and "mwc" memory commands. These are cyclic
4201 This command will print 4 bytes (10,11,12,13) each 500 ms.
4203 => mwc.l 100 12345678 10
4204 This command will write 12345678 to address 100 all 10 ms.
4206 This only takes effect if the memory commands are activated
4207 globally (CONFIG_CMD_MEM).
4209 - CONFIG_SKIP_LOWLEVEL_INIT
4210 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4211 low level initializations (like setting up the memory
4212 controller) are omitted and/or U-Boot does not
4213 relocate itself into RAM.
4215 Normally this variable MUST NOT be defined. The only
4216 exception is when U-Boot is loaded (to RAM) by some
4217 other boot loader or by a debugger which performs
4218 these initializations itself.
4221 Modifies the behaviour of start.S when compiling a loader
4222 that is executed before the actual U-Boot. E.g. when
4223 compiling a NAND SPL.
4225 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4226 Only for 85xx systems. If this variable is specified, the section
4227 .resetvec is not kept and the section .bootpg is placed in the
4228 previous 4k of the .text section.
4230 - CONFIG_ARCH_MAP_SYSMEM
4231 Generally U-Boot (and in particular the md command) uses
4232 effective address. It is therefore not necessary to regard
4233 U-Boot address as virtual addresses that need to be translated
4234 to physical addresses. However, sandbox requires this, since
4235 it maintains its own little RAM buffer which contains all
4236 addressable memory. This option causes some memory accesses
4237 to be mapped through map_sysmem() / unmap_sysmem().
4239 - CONFIG_USE_ARCH_MEMCPY
4240 CONFIG_USE_ARCH_MEMSET
4241 If these options are used a optimized version of memcpy/memset will
4242 be used if available. These functions may be faster under some
4243 conditions but may increase the binary size.
4245 - CONFIG_X86_RESET_VECTOR
4246 If defined, the x86 reset vector code is included. This is not
4247 needed when U-Boot is running from Coreboot.
4250 Defines the MPU clock speed (in MHz).
4252 NOTE : currently only supported on AM335x platforms.
4254 Freescale QE/FMAN Firmware Support:
4255 -----------------------------------
4257 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4258 loading of "firmware", which is encoded in the QE firmware binary format.
4259 This firmware often needs to be loaded during U-Boot booting, so macros
4260 are used to identify the storage device (NOR flash, SPI, etc) and the address
4263 - CONFIG_SYS_QE_FMAN_FW_ADDR
4264 The address in the storage device where the firmware is located. The
4265 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4268 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4269 The maximum possible size of the firmware. The firmware binary format
4270 has a field that specifies the actual size of the firmware, but it
4271 might not be possible to read any part of the firmware unless some
4272 local storage is allocated to hold the entire firmware first.
4274 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4275 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4276 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4277 virtual address in NOR flash.
4279 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4280 Specifies that QE/FMAN firmware is located in NAND flash.
4281 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4283 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4284 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4285 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4287 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4288 Specifies that QE/FMAN firmware is located on the primary SPI
4289 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4291 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4292 Specifies that QE/FMAN firmware is located in the remote (master)
4293 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4294 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4295 window->master inbound window->master LAW->the ucode address in
4296 master's memory space.
4298 Building the Software:
4299 ======================
4301 Building U-Boot has been tested in several native build environments
4302 and in many different cross environments. Of course we cannot support
4303 all possibly existing versions of cross development tools in all
4304 (potentially obsolete) versions. In case of tool chain problems we
4305 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4306 which is extensively used to build and test U-Boot.
4308 If you are not using a native environment, it is assumed that you
4309 have GNU cross compiling tools available in your path. In this case,
4310 you must set the environment variable CROSS_COMPILE in your shell.
4311 Note that no changes to the Makefile or any other source files are
4312 necessary. For example using the ELDK on a 4xx CPU, please enter:
4314 $ CROSS_COMPILE=ppc_4xx-
4315 $ export CROSS_COMPILE
4317 Note: If you wish to generate Windows versions of the utilities in
4318 the tools directory you can use the MinGW toolchain
4319 (http://www.mingw.org). Set your HOST tools to the MinGW
4320 toolchain and execute 'make tools'. For example:
4322 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4324 Binaries such as tools/mkimage.exe will be created which can
4325 be executed on computers running Windows.
4327 U-Boot is intended to be simple to build. After installing the
4328 sources you must configure U-Boot for one specific board type. This
4333 where "NAME_config" is the name of one of the existing configu-
4334 rations; see boards.cfg for supported names.
4336 Note: for some board special configuration names may exist; check if
4337 additional information is available from the board vendor; for
4338 instance, the TQM823L systems are available without (standard)
4339 or with LCD support. You can select such additional "features"
4340 when choosing the configuration, i. e.
4343 - will configure for a plain TQM823L, i. e. no LCD support
4345 make TQM823L_LCD_config
4346 - will configure for a TQM823L with U-Boot console on LCD
4351 Finally, type "make all", and you should get some working U-Boot
4352 images ready for download to / installation on your system:
4354 - "u-boot.bin" is a raw binary image
4355 - "u-boot" is an image in ELF binary format
4356 - "u-boot.srec" is in Motorola S-Record format
4358 By default the build is performed locally and the objects are saved
4359 in the source directory. One of the two methods can be used to change
4360 this behavior and build U-Boot to some external directory:
4362 1. Add O= to the make command line invocations:
4364 make O=/tmp/build distclean
4365 make O=/tmp/build NAME_config
4366 make O=/tmp/build all
4368 2. Set environment variable BUILD_DIR to point to the desired location:
4370 export BUILD_DIR=/tmp/build
4375 Note that the command line "O=" setting overrides the BUILD_DIR environment
4379 Please be aware that the Makefiles assume you are using GNU make, so
4380 for instance on NetBSD you might need to use "gmake" instead of
4384 If the system board that you have is not listed, then you will need
4385 to port U-Boot to your hardware platform. To do this, follow these
4388 1. Add a new configuration option for your board to the toplevel
4389 "boards.cfg" file, using the existing entries as examples.
4390 Follow the instructions there to keep the boards in order.
4391 2. Create a new directory to hold your board specific code. Add any
4392 files you need. In your board directory, you will need at least
4393 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4394 3. Create a new configuration file "include/configs/<board>.h" for
4396 3. If you're porting U-Boot to a new CPU, then also create a new
4397 directory to hold your CPU specific code. Add any files you need.
4398 4. Run "make <board>_config" with your new name.
4399 5. Type "make", and you should get a working "u-boot.srec" file
4400 to be installed on your target system.
4401 6. Debug and solve any problems that might arise.
4402 [Of course, this last step is much harder than it sounds.]
4405 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4406 ==============================================================
4408 If you have modified U-Boot sources (for instance added a new board
4409 or support for new devices, a new CPU, etc.) you are expected to
4410 provide feedback to the other developers. The feedback normally takes
4411 the form of a "patch", i. e. a context diff against a certain (latest
4412 official or latest in the git repository) version of U-Boot sources.
4414 But before you submit such a patch, please verify that your modifi-
4415 cation did not break existing code. At least make sure that *ALL* of
4416 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4417 just run the "MAKEALL" script, which will configure and build U-Boot
4418 for ALL supported system. Be warned, this will take a while. You can
4419 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4420 environment variable to the script, i. e. to use the ELDK cross tools
4423 CROSS_COMPILE=ppc_8xx- MAKEALL
4425 or to build on a native PowerPC system you can type
4427 CROSS_COMPILE=' ' MAKEALL
4429 When using the MAKEALL script, the default behaviour is to build
4430 U-Boot in the source directory. This location can be changed by
4431 setting the BUILD_DIR environment variable. Also, for each target
4432 built, the MAKEALL script saves two log files (<target>.ERR and
4433 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4434 location can be changed by setting the MAKEALL_LOGDIR environment
4435 variable. For example:
4437 export BUILD_DIR=/tmp/build
4438 export MAKEALL_LOGDIR=/tmp/log
4439 CROSS_COMPILE=ppc_8xx- MAKEALL
4441 With the above settings build objects are saved in the /tmp/build,
4442 log files are saved in the /tmp/log and the source tree remains clean
4443 during the whole build process.
4446 See also "U-Boot Porting Guide" below.
4449 Monitor Commands - Overview:
4450 ============================
4452 go - start application at address 'addr'
4453 run - run commands in an environment variable
4454 bootm - boot application image from memory
4455 bootp - boot image via network using BootP/TFTP protocol
4456 bootz - boot zImage from memory
4457 tftpboot- boot image via network using TFTP protocol
4458 and env variables "ipaddr" and "serverip"
4459 (and eventually "gatewayip")
4460 tftpput - upload a file via network using TFTP protocol
4461 rarpboot- boot image via network using RARP/TFTP protocol
4462 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4463 loads - load S-Record file over serial line
4464 loadb - load binary file over serial line (kermit mode)
4466 mm - memory modify (auto-incrementing)
4467 nm - memory modify (constant address)
4468 mw - memory write (fill)
4470 cmp - memory compare
4471 crc32 - checksum calculation
4472 i2c - I2C sub-system
4473 sspi - SPI utility commands
4474 base - print or set address offset
4475 printenv- print environment variables
4476 setenv - set environment variables
4477 saveenv - save environment variables to persistent storage
4478 protect - enable or disable FLASH write protection
4479 erase - erase FLASH memory
4480 flinfo - print FLASH memory information
4481 nand - NAND memory operations (see doc/README.nand)
4482 bdinfo - print Board Info structure
4483 iminfo - print header information for application image
4484 coninfo - print console devices and informations
4485 ide - IDE sub-system
4486 loop - infinite loop on address range
4487 loopw - infinite write loop on address range
4488 mtest - simple RAM test
4489 icache - enable or disable instruction cache
4490 dcache - enable or disable data cache
4491 reset - Perform RESET of the CPU
4492 echo - echo args to console
4493 version - print monitor version
4494 help - print online help
4495 ? - alias for 'help'
4498 Monitor Commands - Detailed Description:
4499 ========================================
4503 For now: just type "help <command>".
4506 Environment Variables:
4507 ======================
4509 U-Boot supports user configuration using Environment Variables which
4510 can be made persistent by saving to Flash memory.
4512 Environment Variables are set using "setenv", printed using
4513 "printenv", and saved to Flash using "saveenv". Using "setenv"
4514 without a value can be used to delete a variable from the
4515 environment. As long as you don't save the environment you are
4516 working with an in-memory copy. In case the Flash area containing the
4517 environment is erased by accident, a default environment is provided.
4519 Some configuration options can be set using Environment Variables.
4521 List of environment variables (most likely not complete):
4523 baudrate - see CONFIG_BAUDRATE
4525 bootdelay - see CONFIG_BOOTDELAY
4527 bootcmd - see CONFIG_BOOTCOMMAND
4529 bootargs - Boot arguments when booting an RTOS image
4531 bootfile - Name of the image to load with TFTP
4533 bootm_low - Memory range available for image processing in the bootm
4534 command can be restricted. This variable is given as
4535 a hexadecimal number and defines lowest address allowed
4536 for use by the bootm command. See also "bootm_size"
4537 environment variable. Address defined by "bootm_low" is
4538 also the base of the initial memory mapping for the Linux
4539 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4542 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4543 This variable is given as a hexadecimal number and it
4544 defines the size of the memory region starting at base
4545 address bootm_low that is accessible by the Linux kernel
4546 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4547 as the default value if it is defined, and bootm_size is
4550 bootm_size - Memory range available for image processing in the bootm
4551 command can be restricted. This variable is given as
4552 a hexadecimal number and defines the size of the region
4553 allowed for use by the bootm command. See also "bootm_low"
4554 environment variable.
4556 updatefile - Location of the software update file on a TFTP server, used
4557 by the automatic software update feature. Please refer to
4558 documentation in doc/README.update for more details.
4560 autoload - if set to "no" (any string beginning with 'n'),
4561 "bootp" will just load perform a lookup of the
4562 configuration from the BOOTP server, but not try to
4563 load any image using TFTP
4565 autostart - if set to "yes", an image loaded using the "bootp",
4566 "rarpboot", "tftpboot" or "diskboot" commands will
4567 be automatically started (by internally calling
4570 If set to "no", a standalone image passed to the
4571 "bootm" command will be copied to the load address
4572 (and eventually uncompressed), but NOT be started.
4573 This can be used to load and uncompress arbitrary
4576 fdt_high - if set this restricts the maximum address that the
4577 flattened device tree will be copied into upon boot.
4578 For example, if you have a system with 1 GB memory
4579 at physical address 0x10000000, while Linux kernel
4580 only recognizes the first 704 MB as low memory, you
4581 may need to set fdt_high as 0x3C000000 to have the
4582 device tree blob be copied to the maximum address
4583 of the 704 MB low memory, so that Linux kernel can
4584 access it during the boot procedure.
4586 If this is set to the special value 0xFFFFFFFF then
4587 the fdt will not be copied at all on boot. For this
4588 to work it must reside in writable memory, have
4589 sufficient padding on the end of it for u-boot to
4590 add the information it needs into it, and the memory
4591 must be accessible by the kernel.
4593 fdtcontroladdr- if set this is the address of the control flattened
4594 device tree used by U-Boot when CONFIG_OF_CONTROL is
4597 i2cfast - (PPC405GP|PPC405EP only)
4598 if set to 'y' configures Linux I2C driver for fast
4599 mode (400kHZ). This environment variable is used in
4600 initialization code. So, for changes to be effective
4601 it must be saved and board must be reset.
4603 initrd_high - restrict positioning of initrd images:
4604 If this variable is not set, initrd images will be
4605 copied to the highest possible address in RAM; this
4606 is usually what you want since it allows for
4607 maximum initrd size. If for some reason you want to
4608 make sure that the initrd image is loaded below the
4609 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4610 variable to a value of "no" or "off" or "0".
4611 Alternatively, you can set it to a maximum upper
4612 address to use (U-Boot will still check that it
4613 does not overwrite the U-Boot stack and data).
4615 For instance, when you have a system with 16 MB
4616 RAM, and want to reserve 4 MB from use by Linux,
4617 you can do this by adding "mem=12M" to the value of
4618 the "bootargs" variable. However, now you must make
4619 sure that the initrd image is placed in the first
4620 12 MB as well - this can be done with
4622 setenv initrd_high 00c00000
4624 If you set initrd_high to 0xFFFFFFFF, this is an
4625 indication to U-Boot that all addresses are legal
4626 for the Linux kernel, including addresses in flash
4627 memory. In this case U-Boot will NOT COPY the
4628 ramdisk at all. This may be useful to reduce the
4629 boot time on your system, but requires that this
4630 feature is supported by your Linux kernel.
4632 ipaddr - IP address; needed for tftpboot command
4634 loadaddr - Default load address for commands like "bootp",
4635 "rarpboot", "tftpboot", "loadb" or "diskboot"
4637 loads_echo - see CONFIG_LOADS_ECHO
4639 serverip - TFTP server IP address; needed for tftpboot command
4641 bootretry - see CONFIG_BOOT_RETRY_TIME
4643 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4645 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4647 ethprime - controls which interface is used first.
4649 ethact - controls which interface is currently active.
4650 For example you can do the following
4652 => setenv ethact FEC
4653 => ping 192.168.0.1 # traffic sent on FEC
4654 => setenv ethact SCC
4655 => ping 10.0.0.1 # traffic sent on SCC
4657 ethrotate - When set to "no" U-Boot does not go through all
4658 available network interfaces.
4659 It just stays at the currently selected interface.
4661 netretry - When set to "no" each network operation will
4662 either succeed or fail without retrying.
4663 When set to "once" the network operation will
4664 fail when all the available network interfaces
4665 are tried once without success.
4666 Useful on scripts which control the retry operation
4669 npe_ucode - set load address for the NPE microcode
4671 tftpsrcport - If this is set, the value is used for TFTP's
4674 tftpdstport - If this is set, the value is used for TFTP's UDP
4675 destination port instead of the Well Know Port 69.
4677 tftpblocksize - Block size to use for TFTP transfers; if not set,
4678 we use the TFTP server's default block size
4680 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4681 seconds, minimum value is 1000 = 1 second). Defines
4682 when a packet is considered to be lost so it has to
4683 be retransmitted. The default is 5000 = 5 seconds.
4684 Lowering this value may make downloads succeed
4685 faster in networks with high packet loss rates or
4686 with unreliable TFTP servers.
4688 vlan - When set to a value < 4095 the traffic over
4689 Ethernet is encapsulated/received over 802.1q
4692 The following image location variables contain the location of images
4693 used in booting. The "Image" column gives the role of the image and is
4694 not an environment variable name. The other columns are environment
4695 variable names. "File Name" gives the name of the file on a TFTP
4696 server, "RAM Address" gives the location in RAM the image will be
4697 loaded to, and "Flash Location" gives the image's address in NOR
4698 flash or offset in NAND flash.
4700 *Note* - these variables don't have to be defined for all boards, some
4701 boards currenlty use other variables for these purposes, and some
4702 boards use these variables for other purposes.
4704 Image File Name RAM Address Flash Location
4705 ----- --------- ----------- --------------
4706 u-boot u-boot u-boot_addr_r u-boot_addr
4707 Linux kernel bootfile kernel_addr_r kernel_addr
4708 device tree blob fdtfile fdt_addr_r fdt_addr
4709 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4711 The following environment variables may be used and automatically
4712 updated by the network boot commands ("bootp" and "rarpboot"),
4713 depending the information provided by your boot server:
4715 bootfile - see above
4716 dnsip - IP address of your Domain Name Server
4717 dnsip2 - IP address of your secondary Domain Name Server
4718 gatewayip - IP address of the Gateway (Router) to use
4719 hostname - Target hostname
4721 netmask - Subnet Mask
4722 rootpath - Pathname of the root filesystem on the NFS server
4723 serverip - see above
4726 There are two special Environment Variables:
4728 serial# - contains hardware identification information such
4729 as type string and/or serial number
4730 ethaddr - Ethernet address
4732 These variables can be set only once (usually during manufacturing of
4733 the board). U-Boot refuses to delete or overwrite these variables
4734 once they have been set once.
4737 Further special Environment Variables:
4739 ver - Contains the U-Boot version string as printed
4740 with the "version" command. This variable is
4741 readonly (see CONFIG_VERSION_VARIABLE).
4744 Please note that changes to some configuration parameters may take
4745 only effect after the next boot (yes, that's just like Windoze :-).
4748 Callback functions for environment variables:
4749 ---------------------------------------------
4751 For some environment variables, the behavior of u-boot needs to change
4752 when their values are changed. This functionailty allows functions to
4753 be associated with arbitrary variables. On creation, overwrite, or
4754 deletion, the callback will provide the opportunity for some side
4755 effect to happen or for the change to be rejected.
4757 The callbacks are named and associated with a function using the
4758 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4760 These callbacks are associated with variables in one of two ways. The
4761 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4762 in the board configuration to a string that defines a list of
4763 associations. The list must be in the following format:
4765 entry = variable_name[:callback_name]
4768 If the callback name is not specified, then the callback is deleted.
4769 Spaces are also allowed anywhere in the list.
4771 Callbacks can also be associated by defining the ".callbacks" variable
4772 with the same list format above. Any association in ".callbacks" will
4773 override any association in the static list. You can define
4774 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4775 ".callbacks" envirnoment variable in the default or embedded environment.
4778 Command Line Parsing:
4779 =====================
4781 There are two different command line parsers available with U-Boot:
4782 the old "simple" one, and the much more powerful "hush" shell:
4784 Old, simple command line parser:
4785 --------------------------------
4787 - supports environment variables (through setenv / saveenv commands)
4788 - several commands on one line, separated by ';'
4789 - variable substitution using "... ${name} ..." syntax
4790 - special characters ('$', ';') can be escaped by prefixing with '\',
4792 setenv bootcmd bootm \${address}
4793 - You can also escape text by enclosing in single apostrophes, for example:
4794 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4799 - similar to Bourne shell, with control structures like
4800 if...then...else...fi, for...do...done; while...do...done,
4801 until...do...done, ...
4802 - supports environment ("global") variables (through setenv / saveenv
4803 commands) and local shell variables (through standard shell syntax
4804 "name=value"); only environment variables can be used with "run"
4810 (1) If a command line (or an environment variable executed by a "run"
4811 command) contains several commands separated by semicolon, and
4812 one of these commands fails, then the remaining commands will be
4815 (2) If you execute several variables with one call to run (i. e.
4816 calling run with a list of variables as arguments), any failing
4817 command will cause "run" to terminate, i. e. the remaining
4818 variables are not executed.
4820 Note for Redundant Ethernet Interfaces:
4821 =======================================
4823 Some boards come with redundant Ethernet interfaces; U-Boot supports
4824 such configurations and is capable of automatic selection of a
4825 "working" interface when needed. MAC assignment works as follows:
4827 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4828 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4829 "eth1addr" (=>eth1), "eth2addr", ...
4831 If the network interface stores some valid MAC address (for instance
4832 in SROM), this is used as default address if there is NO correspon-
4833 ding setting in the environment; if the corresponding environment
4834 variable is set, this overrides the settings in the card; that means:
4836 o If the SROM has a valid MAC address, and there is no address in the
4837 environment, the SROM's address is used.
4839 o If there is no valid address in the SROM, and a definition in the
4840 environment exists, then the value from the environment variable is
4843 o If both the SROM and the environment contain a MAC address, and
4844 both addresses are the same, this MAC address is used.
4846 o If both the SROM and the environment contain a MAC address, and the
4847 addresses differ, the value from the environment is used and a
4850 o If neither SROM nor the environment contain a MAC address, an error
4853 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4854 will be programmed into hardware as part of the initialization process. This
4855 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4856 The naming convention is as follows:
4857 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4862 U-Boot is capable of booting (and performing other auxiliary operations on)
4863 images in two formats:
4865 New uImage format (FIT)
4866 -----------------------
4868 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4869 to Flattened Device Tree). It allows the use of images with multiple
4870 components (several kernels, ramdisks, etc.), with contents protected by
4871 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4877 Old image format is based on binary files which can be basically anything,
4878 preceded by a special header; see the definitions in include/image.h for
4879 details; basically, the header defines the following image properties:
4881 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4882 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4883 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4884 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4886 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4887 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4888 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4889 * Compression Type (uncompressed, gzip, bzip2)
4895 The header is marked by a special Magic Number, and both the header
4896 and the data portions of the image are secured against corruption by
4903 Although U-Boot should support any OS or standalone application
4904 easily, the main focus has always been on Linux during the design of
4907 U-Boot includes many features that so far have been part of some
4908 special "boot loader" code within the Linux kernel. Also, any
4909 "initrd" images to be used are no longer part of one big Linux image;
4910 instead, kernel and "initrd" are separate images. This implementation
4911 serves several purposes:
4913 - the same features can be used for other OS or standalone
4914 applications (for instance: using compressed images to reduce the
4915 Flash memory footprint)
4917 - it becomes much easier to port new Linux kernel versions because
4918 lots of low-level, hardware dependent stuff are done by U-Boot
4920 - the same Linux kernel image can now be used with different "initrd"
4921 images; of course this also means that different kernel images can
4922 be run with the same "initrd". This makes testing easier (you don't
4923 have to build a new "zImage.initrd" Linux image when you just
4924 change a file in your "initrd"). Also, a field-upgrade of the
4925 software is easier now.
4931 Porting Linux to U-Boot based systems:
4932 ---------------------------------------
4934 U-Boot cannot save you from doing all the necessary modifications to
4935 configure the Linux device drivers for use with your target hardware
4936 (no, we don't intend to provide a full virtual machine interface to
4939 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4941 Just make sure your machine specific header file (for instance
4942 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4943 Information structure as we define in include/asm-<arch>/u-boot.h,
4944 and make sure that your definition of IMAP_ADDR uses the same value
4945 as your U-Boot configuration in CONFIG_SYS_IMMR.
4948 Configuring the Linux kernel:
4949 -----------------------------
4951 No specific requirements for U-Boot. Make sure you have some root
4952 device (initial ramdisk, NFS) for your target system.
4955 Building a Linux Image:
4956 -----------------------
4958 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4959 not used. If you use recent kernel source, a new build target
4960 "uImage" will exist which automatically builds an image usable by
4961 U-Boot. Most older kernels also have support for a "pImage" target,
4962 which was introduced for our predecessor project PPCBoot and uses a
4963 100% compatible format.
4972 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4973 encapsulate a compressed Linux kernel image with header information,
4974 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4976 * build a standard "vmlinux" kernel image (in ELF binary format):
4978 * convert the kernel into a raw binary image:
4980 ${CROSS_COMPILE}-objcopy -O binary \
4981 -R .note -R .comment \
4982 -S vmlinux linux.bin
4984 * compress the binary image:
4988 * package compressed binary image for U-Boot:
4990 mkimage -A ppc -O linux -T kernel -C gzip \
4991 -a 0 -e 0 -n "Linux Kernel Image" \
4992 -d linux.bin.gz uImage
4995 The "mkimage" tool can also be used to create ramdisk images for use
4996 with U-Boot, either separated from the Linux kernel image, or
4997 combined into one file. "mkimage" encapsulates the images with a 64
4998 byte header containing information about target architecture,
4999 operating system, image type, compression method, entry points, time
5000 stamp, CRC32 checksums, etc.
5002 "mkimage" can be called in two ways: to verify existing images and
5003 print the header information, or to build new images.
5005 In the first form (with "-l" option) mkimage lists the information
5006 contained in the header of an existing U-Boot image; this includes
5007 checksum verification:
5009 tools/mkimage -l image
5010 -l ==> list image header information
5012 The second form (with "-d" option) is used to build a U-Boot image
5013 from a "data file" which is used as image payload:
5015 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5016 -n name -d data_file image
5017 -A ==> set architecture to 'arch'
5018 -O ==> set operating system to 'os'
5019 -T ==> set image type to 'type'
5020 -C ==> set compression type 'comp'
5021 -a ==> set load address to 'addr' (hex)
5022 -e ==> set entry point to 'ep' (hex)
5023 -n ==> set image name to 'name'
5024 -d ==> use image data from 'datafile'
5026 Right now, all Linux kernels for PowerPC systems use the same load
5027 address (0x00000000), but the entry point address depends on the
5030 - 2.2.x kernels have the entry point at 0x0000000C,
5031 - 2.3.x and later kernels have the entry point at 0x00000000.
5033 So a typical call to build a U-Boot image would read:
5035 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5036 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5037 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5038 > examples/uImage.TQM850L
5039 Image Name: 2.4.4 kernel for TQM850L
5040 Created: Wed Jul 19 02:34:59 2000
5041 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5042 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5043 Load Address: 0x00000000
5044 Entry Point: 0x00000000
5046 To verify the contents of the image (or check for corruption):
5048 -> tools/mkimage -l examples/uImage.TQM850L
5049 Image Name: 2.4.4 kernel for TQM850L
5050 Created: Wed Jul 19 02:34:59 2000
5051 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5052 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5053 Load Address: 0x00000000
5054 Entry Point: 0x00000000
5056 NOTE: for embedded systems where boot time is critical you can trade
5057 speed for memory and install an UNCOMPRESSED image instead: this
5058 needs more space in Flash, but boots much faster since it does not
5059 need to be uncompressed:
5061 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5062 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5063 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5064 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5065 > examples/uImage.TQM850L-uncompressed
5066 Image Name: 2.4.4 kernel for TQM850L
5067 Created: Wed Jul 19 02:34:59 2000
5068 Image Type: PowerPC Linux Kernel Image (uncompressed)
5069 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5070 Load Address: 0x00000000
5071 Entry Point: 0x00000000
5074 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5075 when your kernel is intended to use an initial ramdisk:
5077 -> tools/mkimage -n 'Simple Ramdisk Image' \
5078 > -A ppc -O linux -T ramdisk -C gzip \
5079 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5080 Image Name: Simple Ramdisk Image
5081 Created: Wed Jan 12 14:01:50 2000
5082 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5083 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5084 Load Address: 0x00000000
5085 Entry Point: 0x00000000
5088 Installing a Linux Image:
5089 -------------------------
5091 To downloading a U-Boot image over the serial (console) interface,
5092 you must convert the image to S-Record format:
5094 objcopy -I binary -O srec examples/image examples/image.srec
5096 The 'objcopy' does not understand the information in the U-Boot
5097 image header, so the resulting S-Record file will be relative to
5098 address 0x00000000. To load it to a given address, you need to
5099 specify the target address as 'offset' parameter with the 'loads'
5102 Example: install the image to address 0x40100000 (which on the
5103 TQM8xxL is in the first Flash bank):
5105 => erase 40100000 401FFFFF
5111 ## Ready for S-Record download ...
5112 ~>examples/image.srec
5113 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5115 15989 15990 15991 15992
5116 [file transfer complete]
5118 ## Start Addr = 0x00000000
5121 You can check the success of the download using the 'iminfo' command;
5122 this includes a checksum verification so you can be sure no data
5123 corruption happened:
5127 ## Checking Image at 40100000 ...
5128 Image Name: 2.2.13 for initrd on TQM850L
5129 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5130 Data Size: 335725 Bytes = 327 kB = 0 MB
5131 Load Address: 00000000
5132 Entry Point: 0000000c
5133 Verifying Checksum ... OK
5139 The "bootm" command is used to boot an application that is stored in
5140 memory (RAM or Flash). In case of a Linux kernel image, the contents
5141 of the "bootargs" environment variable is passed to the kernel as
5142 parameters. You can check and modify this variable using the
5143 "printenv" and "setenv" commands:
5146 => printenv bootargs
5147 bootargs=root=/dev/ram
5149 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5151 => printenv bootargs
5152 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5155 ## Booting Linux kernel at 40020000 ...
5156 Image Name: 2.2.13 for NFS on TQM850L
5157 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5158 Data Size: 381681 Bytes = 372 kB = 0 MB
5159 Load Address: 00000000
5160 Entry Point: 0000000c
5161 Verifying Checksum ... OK
5162 Uncompressing Kernel Image ... OK
5163 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
5164 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5165 time_init: decrementer frequency = 187500000/60
5166 Calibrating delay loop... 49.77 BogoMIPS
5167 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5170 If you want to boot a Linux kernel with initial RAM disk, you pass
5171 the memory addresses of both the kernel and the initrd image (PPBCOOT
5172 format!) to the "bootm" command:
5174 => imi 40100000 40200000
5176 ## Checking Image at 40100000 ...
5177 Image Name: 2.2.13 for initrd on TQM850L
5178 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5179 Data Size: 335725 Bytes = 327 kB = 0 MB
5180 Load Address: 00000000
5181 Entry Point: 0000000c
5182 Verifying Checksum ... OK
5184 ## Checking Image at 40200000 ...
5185 Image Name: Simple Ramdisk Image
5186 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5187 Data Size: 566530 Bytes = 553 kB = 0 MB
5188 Load Address: 00000000
5189 Entry Point: 00000000
5190 Verifying Checksum ... OK
5192 => bootm 40100000 40200000
5193 ## Booting Linux kernel at 40100000 ...
5194 Image Name: 2.2.13 for initrd on TQM850L
5195 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5196 Data Size: 335725 Bytes = 327 kB = 0 MB
5197 Load Address: 00000000
5198 Entry Point: 0000000c
5199 Verifying Checksum ... OK
5200 Uncompressing Kernel Image ... OK
5201 ## Loading RAMDisk Image at 40200000 ...
5202 Image Name: Simple Ramdisk Image
5203 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5204 Data Size: 566530 Bytes = 553 kB = 0 MB
5205 Load Address: 00000000
5206 Entry Point: 00000000
5207 Verifying Checksum ... OK
5208 Loading Ramdisk ... OK
5209 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
5210 Boot arguments: root=/dev/ram
5211 time_init: decrementer frequency = 187500000/60
5212 Calibrating delay loop... 49.77 BogoMIPS
5214 RAMDISK: Compressed image found at block 0
5215 VFS: Mounted root (ext2 filesystem).
5219 Boot Linux and pass a flat device tree:
5222 First, U-Boot must be compiled with the appropriate defines. See the section
5223 titled "Linux Kernel Interface" above for a more in depth explanation. The
5224 following is an example of how to start a kernel and pass an updated
5230 oft=oftrees/mpc8540ads.dtb
5231 => tftp $oftaddr $oft
5232 Speed: 1000, full duplex
5234 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5235 Filename 'oftrees/mpc8540ads.dtb'.
5236 Load address: 0x300000
5239 Bytes transferred = 4106 (100a hex)
5240 => tftp $loadaddr $bootfile
5241 Speed: 1000, full duplex
5243 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5245 Load address: 0x200000
5246 Loading:############
5248 Bytes transferred = 1029407 (fb51f hex)
5253 => bootm $loadaddr - $oftaddr
5254 ## Booting image at 00200000 ...
5255 Image Name: Linux-2.6.17-dirty
5256 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5257 Data Size: 1029343 Bytes = 1005.2 kB
5258 Load Address: 00000000
5259 Entry Point: 00000000
5260 Verifying Checksum ... OK
5261 Uncompressing Kernel Image ... OK
5262 Booting using flat device tree at 0x300000
5263 Using MPC85xx ADS machine description
5264 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5268 More About U-Boot Image Types:
5269 ------------------------------
5271 U-Boot supports the following image types:
5273 "Standalone Programs" are directly runnable in the environment
5274 provided by U-Boot; it is expected that (if they behave
5275 well) you can continue to work in U-Boot after return from
5276 the Standalone Program.
5277 "OS Kernel Images" are usually images of some Embedded OS which
5278 will take over control completely. Usually these programs
5279 will install their own set of exception handlers, device
5280 drivers, set up the MMU, etc. - this means, that you cannot
5281 expect to re-enter U-Boot except by resetting the CPU.
5282 "RAMDisk Images" are more or less just data blocks, and their
5283 parameters (address, size) are passed to an OS kernel that is
5285 "Multi-File Images" contain several images, typically an OS
5286 (Linux) kernel image and one or more data images like
5287 RAMDisks. This construct is useful for instance when you want
5288 to boot over the network using BOOTP etc., where the boot
5289 server provides just a single image file, but you want to get
5290 for instance an OS kernel and a RAMDisk image.
5292 "Multi-File Images" start with a list of image sizes, each
5293 image size (in bytes) specified by an "uint32_t" in network
5294 byte order. This list is terminated by an "(uint32_t)0".
5295 Immediately after the terminating 0 follow the images, one by
5296 one, all aligned on "uint32_t" boundaries (size rounded up to
5297 a multiple of 4 bytes).
5299 "Firmware Images" are binary images containing firmware (like
5300 U-Boot or FPGA images) which usually will be programmed to
5303 "Script files" are command sequences that will be executed by
5304 U-Boot's command interpreter; this feature is especially
5305 useful when you configure U-Boot to use a real shell (hush)
5306 as command interpreter.
5308 Booting the Linux zImage:
5309 -------------------------
5311 On some platforms, it's possible to boot Linux zImage. This is done
5312 using the "bootz" command. The syntax of "bootz" command is the same
5313 as the syntax of "bootm" command.
5315 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5316 kernel with raw initrd images. The syntax is slightly different, the
5317 address of the initrd must be augmented by it's size, in the following
5318 format: "<initrd addres>:<initrd size>".
5324 One of the features of U-Boot is that you can dynamically load and
5325 run "standalone" applications, which can use some resources of
5326 U-Boot like console I/O functions or interrupt services.
5328 Two simple examples are included with the sources:
5333 'examples/hello_world.c' contains a small "Hello World" Demo
5334 application; it is automatically compiled when you build U-Boot.
5335 It's configured to run at address 0x00040004, so you can play with it
5339 ## Ready for S-Record download ...
5340 ~>examples/hello_world.srec
5341 1 2 3 4 5 6 7 8 9 10 11 ...
5342 [file transfer complete]
5344 ## Start Addr = 0x00040004
5346 => go 40004 Hello World! This is a test.
5347 ## Starting application at 0x00040004 ...
5358 Hit any key to exit ...
5360 ## Application terminated, rc = 0x0
5362 Another example, which demonstrates how to register a CPM interrupt
5363 handler with the U-Boot code, can be found in 'examples/timer.c'.
5364 Here, a CPM timer is set up to generate an interrupt every second.
5365 The interrupt service routine is trivial, just printing a '.'
5366 character, but this is just a demo program. The application can be
5367 controlled by the following keys:
5369 ? - print current values og the CPM Timer registers
5370 b - enable interrupts and start timer
5371 e - stop timer and disable interrupts
5372 q - quit application
5375 ## Ready for S-Record download ...
5376 ~>examples/timer.srec
5377 1 2 3 4 5 6 7 8 9 10 11 ...
5378 [file transfer complete]
5380 ## Start Addr = 0x00040004
5383 ## Starting application at 0x00040004 ...
5386 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5389 [q, b, e, ?] Set interval 1000000 us
5392 [q, b, e, ?] ........
5393 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5396 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5399 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5402 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5404 [q, b, e, ?] ...Stopping timer
5406 [q, b, e, ?] ## Application terminated, rc = 0x0
5412 Over time, many people have reported problems when trying to use the
5413 "minicom" terminal emulation program for serial download. I (wd)
5414 consider minicom to be broken, and recommend not to use it. Under
5415 Unix, I recommend to use C-Kermit for general purpose use (and
5416 especially for kermit binary protocol download ("loadb" command), and
5417 use "cu" for S-Record download ("loads" command). See
5418 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5419 for help with kermit.
5422 Nevertheless, if you absolutely want to use it try adding this
5423 configuration to your "File transfer protocols" section:
5425 Name Program Name U/D FullScr IO-Red. Multi
5426 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5427 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5433 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5434 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5436 Building requires a cross environment; it is known to work on
5437 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5438 need gmake since the Makefiles are not compatible with BSD make).
5439 Note that the cross-powerpc package does not install include files;
5440 attempting to build U-Boot will fail because <machine/ansi.h> is
5441 missing. This file has to be installed and patched manually:
5443 # cd /usr/pkg/cross/powerpc-netbsd/include
5445 # ln -s powerpc machine
5446 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5447 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5449 Native builds *don't* work due to incompatibilities between native
5450 and U-Boot include files.
5452 Booting assumes that (the first part of) the image booted is a
5453 stage-2 loader which in turn loads and then invokes the kernel
5454 proper. Loader sources will eventually appear in the NetBSD source
5455 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5456 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5459 Implementation Internals:
5460 =========================
5462 The following is not intended to be a complete description of every
5463 implementation detail. However, it should help to understand the
5464 inner workings of U-Boot and make it easier to port it to custom
5468 Initial Stack, Global Data:
5469 ---------------------------
5471 The implementation of U-Boot is complicated by the fact that U-Boot
5472 starts running out of ROM (flash memory), usually without access to
5473 system RAM (because the memory controller is not initialized yet).
5474 This means that we don't have writable Data or BSS segments, and BSS
5475 is not initialized as zero. To be able to get a C environment working
5476 at all, we have to allocate at least a minimal stack. Implementation
5477 options for this are defined and restricted by the CPU used: Some CPU
5478 models provide on-chip memory (like the IMMR area on MPC8xx and
5479 MPC826x processors), on others (parts of) the data cache can be
5480 locked as (mis-) used as memory, etc.
5482 Chris Hallinan posted a good summary of these issues to the
5483 U-Boot mailing list:
5485 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5487 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5490 Correct me if I'm wrong, folks, but the way I understand it
5491 is this: Using DCACHE as initial RAM for Stack, etc, does not
5492 require any physical RAM backing up the cache. The cleverness
5493 is that the cache is being used as a temporary supply of
5494 necessary storage before the SDRAM controller is setup. It's
5495 beyond the scope of this list to explain the details, but you
5496 can see how this works by studying the cache architecture and
5497 operation in the architecture and processor-specific manuals.
5499 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5500 is another option for the system designer to use as an
5501 initial stack/RAM area prior to SDRAM being available. Either
5502 option should work for you. Using CS 4 should be fine if your
5503 board designers haven't used it for something that would
5504 cause you grief during the initial boot! It is frequently not
5507 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5508 with your processor/board/system design. The default value
5509 you will find in any recent u-boot distribution in
5510 walnut.h should work for you. I'd set it to a value larger
5511 than your SDRAM module. If you have a 64MB SDRAM module, set
5512 it above 400_0000. Just make sure your board has no resources
5513 that are supposed to respond to that address! That code in
5514 start.S has been around a while and should work as is when
5515 you get the config right.
5520 It is essential to remember this, since it has some impact on the C
5521 code for the initialization procedures:
5523 * Initialized global data (data segment) is read-only. Do not attempt
5526 * Do not use any uninitialized global data (or implicitely initialized
5527 as zero data - BSS segment) at all - this is undefined, initiali-
5528 zation is performed later (when relocating to RAM).
5530 * Stack space is very limited. Avoid big data buffers or things like
5533 Having only the stack as writable memory limits means we cannot use
5534 normal global data to share information beween the code. But it
5535 turned out that the implementation of U-Boot can be greatly
5536 simplified by making a global data structure (gd_t) available to all
5537 functions. We could pass a pointer to this data as argument to _all_
5538 functions, but this would bloat the code. Instead we use a feature of
5539 the GCC compiler (Global Register Variables) to share the data: we
5540 place a pointer (gd) to the global data into a register which we
5541 reserve for this purpose.
5543 When choosing a register for such a purpose we are restricted by the
5544 relevant (E)ABI specifications for the current architecture, and by
5545 GCC's implementation.
5547 For PowerPC, the following registers have specific use:
5549 R2: reserved for system use
5550 R3-R4: parameter passing and return values
5551 R5-R10: parameter passing
5552 R13: small data area pointer
5556 (U-Boot also uses R12 as internal GOT pointer. r12
5557 is a volatile register so r12 needs to be reset when
5558 going back and forth between asm and C)
5560 ==> U-Boot will use R2 to hold a pointer to the global data
5562 Note: on PPC, we could use a static initializer (since the
5563 address of the global data structure is known at compile time),
5564 but it turned out that reserving a register results in somewhat
5565 smaller code - although the code savings are not that big (on
5566 average for all boards 752 bytes for the whole U-Boot image,
5567 624 text + 127 data).
5569 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5570 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5572 ==> U-Boot will use P3 to hold a pointer to the global data
5574 On ARM, the following registers are used:
5576 R0: function argument word/integer result
5577 R1-R3: function argument word
5579 R10: stack limit (used only if stack checking if enabled)
5580 R11: argument (frame) pointer
5581 R12: temporary workspace
5584 R15: program counter
5586 ==> U-Boot will use R8 to hold a pointer to the global data
5588 On Nios II, the ABI is documented here:
5589 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5591 ==> U-Boot will use gp to hold a pointer to the global data
5593 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5594 to access small data sections, so gp is free.
5596 On NDS32, the following registers are used:
5598 R0-R1: argument/return
5600 R15: temporary register for assembler
5601 R16: trampoline register
5602 R28: frame pointer (FP)
5603 R29: global pointer (GP)
5604 R30: link register (LP)
5605 R31: stack pointer (SP)
5606 PC: program counter (PC)
5608 ==> U-Boot will use R10 to hold a pointer to the global data
5610 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5611 or current versions of GCC may "optimize" the code too much.
5616 U-Boot runs in system state and uses physical addresses, i.e. the
5617 MMU is not used either for address mapping nor for memory protection.
5619 The available memory is mapped to fixed addresses using the memory
5620 controller. In this process, a contiguous block is formed for each
5621 memory type (Flash, SDRAM, SRAM), even when it consists of several
5622 physical memory banks.
5624 U-Boot is installed in the first 128 kB of the first Flash bank (on
5625 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5626 booting and sizing and initializing DRAM, the code relocates itself
5627 to the upper end of DRAM. Immediately below the U-Boot code some
5628 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5629 configuration setting]. Below that, a structure with global Board
5630 Info data is placed, followed by the stack (growing downward).
5632 Additionally, some exception handler code is copied to the low 8 kB
5633 of DRAM (0x00000000 ... 0x00001FFF).
5635 So a typical memory configuration with 16 MB of DRAM could look like
5638 0x0000 0000 Exception Vector code
5641 0x0000 2000 Free for Application Use
5647 0x00FB FF20 Monitor Stack (Growing downward)
5648 0x00FB FFAC Board Info Data and permanent copy of global data
5649 0x00FC 0000 Malloc Arena
5652 0x00FE 0000 RAM Copy of Monitor Code
5653 ... eventually: LCD or video framebuffer
5654 ... eventually: pRAM (Protected RAM - unchanged by reset)
5655 0x00FF FFFF [End of RAM]
5658 System Initialization:
5659 ----------------------
5661 In the reset configuration, U-Boot starts at the reset entry point
5662 (on most PowerPC systems at address 0x00000100). Because of the reset
5663 configuration for CS0# this is a mirror of the onboard Flash memory.
5664 To be able to re-map memory U-Boot then jumps to its link address.
5665 To be able to implement the initialization code in C, a (small!)
5666 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5667 which provide such a feature like MPC8xx or MPC8260), or in a locked
5668 part of the data cache. After that, U-Boot initializes the CPU core,
5669 the caches and the SIU.
5671 Next, all (potentially) available memory banks are mapped using a
5672 preliminary mapping. For example, we put them on 512 MB boundaries
5673 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5674 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5675 programmed for SDRAM access. Using the temporary configuration, a
5676 simple memory test is run that determines the size of the SDRAM
5679 When there is more than one SDRAM bank, and the banks are of
5680 different size, the largest is mapped first. For equal size, the first
5681 bank (CS2#) is mapped first. The first mapping is always for address
5682 0x00000000, with any additional banks following immediately to create
5683 contiguous memory starting from 0.
5685 Then, the monitor installs itself at the upper end of the SDRAM area
5686 and allocates memory for use by malloc() and for the global Board
5687 Info data; also, the exception vector code is copied to the low RAM
5688 pages, and the final stack is set up.
5690 Only after this relocation will you have a "normal" C environment;
5691 until that you are restricted in several ways, mostly because you are
5692 running from ROM, and because the code will have to be relocated to a
5696 U-Boot Porting Guide:
5697 ----------------------
5699 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5703 int main(int argc, char *argv[])
5705 sighandler_t no_more_time;
5707 signal(SIGALRM, no_more_time);
5708 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5710 if (available_money > available_manpower) {
5711 Pay consultant to port U-Boot;
5715 Download latest U-Boot source;
5717 Subscribe to u-boot mailing list;
5720 email("Hi, I am new to U-Boot, how do I get started?");
5723 Read the README file in the top level directory;
5724 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5725 Read applicable doc/*.README;
5726 Read the source, Luke;
5727 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5730 if (available_money > toLocalCurrency ($2500))
5733 Add a lot of aggravation and time;
5735 if (a similar board exists) { /* hopefully... */
5736 cp -a board/<similar> board/<myboard>
5737 cp include/configs/<similar>.h include/configs/<myboard>.h
5739 Create your own board support subdirectory;
5740 Create your own board include/configs/<myboard>.h file;
5742 Edit new board/<myboard> files
5743 Edit new include/configs/<myboard>.h
5748 Add / modify source code;
5752 email("Hi, I am having problems...");
5754 Send patch file to the U-Boot email list;
5755 if (reasonable critiques)
5756 Incorporate improvements from email list code review;
5758 Defend code as written;
5764 void no_more_time (int sig)
5773 All contributions to U-Boot should conform to the Linux kernel
5774 coding style; see the file "Documentation/CodingStyle" and the script
5775 "scripts/Lindent" in your Linux kernel source directory.
5777 Source files originating from a different project (for example the
5778 MTD subsystem) are generally exempt from these guidelines and are not
5779 reformated to ease subsequent migration to newer versions of those
5782 Please note that U-Boot is implemented in C (and to some small parts in
5783 Assembler); no C++ is used, so please do not use C++ style comments (//)
5786 Please also stick to the following formatting rules:
5787 - remove any trailing white space
5788 - use TAB characters for indentation and vertical alignment, not spaces
5789 - make sure NOT to use DOS '\r\n' line feeds
5790 - do not add more than 2 consecutive empty lines to source files
5791 - do not add trailing empty lines to source files
5793 Submissions which do not conform to the standards may be returned
5794 with a request to reformat the changes.
5800 Since the number of patches for U-Boot is growing, we need to
5801 establish some rules. Submissions which do not conform to these rules
5802 may be rejected, even when they contain important and valuable stuff.
5804 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5807 see http://lists.denx.de/mailman/listinfo/u-boot
5809 When you send a patch, please include the following information with
5812 * For bug fixes: a description of the bug and how your patch fixes
5813 this bug. Please try to include a way of demonstrating that the
5814 patch actually fixes something.
5816 * For new features: a description of the feature and your
5819 * A CHANGELOG entry as plaintext (separate from the patch)
5821 * For major contributions, your entry to the CREDITS file
5823 * When you add support for a new board, don't forget to add this
5824 board to the MAINTAINERS file, too.
5826 * If your patch adds new configuration options, don't forget to
5827 document these in the README file.
5829 * The patch itself. If you are using git (which is *strongly*
5830 recommended) you can easily generate the patch using the
5831 "git format-patch". If you then use "git send-email" to send it to
5832 the U-Boot mailing list, you will avoid most of the common problems
5833 with some other mail clients.
5835 If you cannot use git, use "diff -purN OLD NEW". If your version of
5836 diff does not support these options, then get the latest version of
5839 The current directory when running this command shall be the parent
5840 directory of the U-Boot source tree (i. e. please make sure that
5841 your patch includes sufficient directory information for the
5844 We prefer patches as plain text. MIME attachments are discouraged,
5845 and compressed attachments must not be used.
5847 * If one logical set of modifications affects or creates several
5848 files, all these changes shall be submitted in a SINGLE patch file.
5850 * Changesets that contain different, unrelated modifications shall be
5851 submitted as SEPARATE patches, one patch per changeset.
5856 * Before sending the patch, run the MAKEALL script on your patched
5857 source tree and make sure that no errors or warnings are reported
5858 for any of the boards.
5860 * Keep your modifications to the necessary minimum: A patch
5861 containing several unrelated changes or arbitrary reformats will be
5862 returned with a request to re-formatting / split it.
5864 * If you modify existing code, make sure that your new code does not
5865 add to the memory footprint of the code ;-) Small is beautiful!
5866 When adding new features, these should compile conditionally only
5867 (using #ifdef), and the resulting code with the new feature
5868 disabled must not need more memory than the old code without your
5871 * Remember that there is a size limit of 100 kB per message on the
5872 u-boot mailing list. Bigger patches will be moderated. If they are
5873 reasonable and not too big, they will be acknowledged. But patches
5874 bigger than the size limit should be avoided.
projects / J-u-boot.git / blob