2 # (C) Copyright 2000 - 2011
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /mips32 Files specific to MIPS32 CPUs
184 /xburst Files specific to Ingenic XBurst CPUs
185 /lib Architecture specific library files
186 /nios2 Files generic to Altera NIOS2 architecture
187 /cpu CPU specific files
188 /lib Architecture specific library files
189 /powerpc Files generic to PowerPC architecture
190 /cpu CPU specific files
191 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
192 /mpc5xx Files specific to Freescale MPC5xx CPUs
193 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
194 /mpc8xx Files specific to Freescale MPC8xx CPUs
195 /mpc8220 Files specific to Freescale MPC8220 CPUs
196 /mpc824x Files specific to Freescale MPC824x CPUs
197 /mpc8260 Files specific to Freescale MPC8260 CPUs
198 /mpc85xx Files specific to Freescale MPC85xx CPUs
199 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
200 /lib Architecture specific library files
201 /sh Files generic to SH architecture
202 /cpu CPU specific files
203 /sh2 Files specific to sh2 CPUs
204 /sh3 Files specific to sh3 CPUs
205 /sh4 Files specific to sh4 CPUs
206 /lib Architecture specific library files
207 /sparc Files generic to SPARC architecture
208 /cpu CPU specific files
209 /leon2 Files specific to Gaisler LEON2 SPARC CPU
210 /leon3 Files specific to Gaisler LEON3 SPARC CPU
211 /lib Architecture specific library files
212 /api Machine/arch independent API for external apps
213 /board Board dependent files
214 /common Misc architecture independent functions
215 /disk Code for disk drive partition handling
216 /doc Documentation (don't expect too much)
217 /drivers Commonly used device drivers
218 /examples Example code for standalone applications, etc.
219 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
220 /include Header Files
221 /lib Files generic to all architectures
222 /libfdt Library files to support flattened device trees
223 /lzma Library files to support LZMA decompression
224 /lzo Library files to support LZO decompression
226 /post Power On Self Test
227 /rtc Real Time Clock drivers
228 /tools Tools to build S-Record or U-Boot images, etc.
230 Software Configuration:
231 =======================
233 Configuration is usually done using C preprocessor defines; the
234 rationale behind that is to avoid dead code whenever possible.
236 There are two classes of configuration variables:
238 * Configuration _OPTIONS_:
239 These are selectable by the user and have names beginning with
242 * Configuration _SETTINGS_:
243 These depend on the hardware etc. and should not be meddled with if
244 you don't know what you're doing; they have names beginning with
247 Later we will add a configuration tool - probably similar to or even
248 identical to what's used for the Linux kernel. Right now, we have to
249 do the configuration by hand, which means creating some symbolic
250 links and editing some configuration files. We use the TQM8xxL boards
254 Selection of Processor Architecture and Board Type:
255 ---------------------------------------------------
257 For all supported boards there are ready-to-use default
258 configurations available; just type "make <board_name>_config".
260 Example: For a TQM823L module type:
265 For the Cogent platform, you need to specify the CPU type as well;
266 e.g. "make cogent_mpc8xx_config". And also configure the cogent
267 directory according to the instructions in cogent/README.
270 Configuration Options:
271 ----------------------
273 Configuration depends on the combination of board and CPU type; all
274 such information is kept in a configuration file
275 "include/configs/<board_name>.h".
277 Example: For a TQM823L module, all configuration settings are in
278 "include/configs/TQM823L.h".
281 Many of the options are named exactly as the corresponding Linux
282 kernel configuration options. The intention is to make it easier to
283 build a config tool - later.
286 The following options need to be configured:
288 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
290 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
292 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
293 Define exactly one, e.g. CONFIG_ATSTK1002
295 - CPU Module Type: (if CONFIG_COGENT is defined)
296 Define exactly one of
298 --- FIXME --- not tested yet:
299 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
300 CONFIG_CMA287_23, CONFIG_CMA287_50
302 - Motherboard Type: (if CONFIG_COGENT is defined)
303 Define exactly one of
304 CONFIG_CMA101, CONFIG_CMA102
306 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
307 Define one or more of
310 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
311 Define one or more of
312 CONFIG_LCD_HEARTBEAT - update a character position on
313 the LCD display every second with
316 - Board flavour: (if CONFIG_MPC8260ADS is defined)
319 CONFIG_SYS_8260ADS - original MPC8260ADS
320 CONFIG_SYS_8266ADS - MPC8266ADS
321 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
322 CONFIG_SYS_8272ADS - MPC8272ADS
324 - Marvell Family Member
325 CONFIG_SYS_MVFS - define it if you want to enable
326 multiple fs option at one time
327 for marvell soc family
329 - MPC824X Family Member (if CONFIG_MPC824X is defined)
330 Define exactly one of
331 CONFIG_MPC8240, CONFIG_MPC8245
333 - 8xx CPU Options: (if using an MPC8xx CPU)
334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
335 get_gclk_freq() cannot work
336 e.g. if there is no 32KHz
337 reference PIT/RTC clock
338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
341 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
342 CONFIG_SYS_8xx_CPUCLK_MIN
343 CONFIG_SYS_8xx_CPUCLK_MAX
344 CONFIG_8xx_CPUCLK_DEFAULT
345 See doc/README.MPC866
347 CONFIG_SYS_MEASURE_CPUCLK
349 Define this to measure the actual CPU clock instead
350 of relying on the correctness of the configured
351 values. Mostly useful for board bringup to make sure
352 the PLL is locked at the intended frequency. Note
353 that this requires a (stable) reference clock (32 kHz
354 RTC clock or CONFIG_SYS_8XX_XIN)
356 CONFIG_SYS_DELAYED_ICACHE
358 Define this option if you want to enable the
359 ICache only when Code runs from RAM.
362 CONFIG_SYS_FSL_TBCLK_DIV
364 Defines the core time base clock divider ratio compared to the
365 system clock. On most PQ3 devices this is 8, on newer QorIQ
366 devices it can be 16 or 32. The ratio varies from SoC to Soc.
368 CONFIG_SYS_FSL_PCIE_COMPAT
370 Defines the string to utilize when trying to match PCIe device
371 tree nodes for the given platform.
373 - Intel Monahans options:
374 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
376 Defines the Monahans run mode to oscillator
377 ratio. Valid values are 8, 16, 24, 31. The core
378 frequency is this value multiplied by 13 MHz.
380 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
382 Defines the Monahans turbo mode to oscillator
383 ratio. Valid values are 1 (default if undefined) and
384 2. The core frequency as calculated above is multiplied
388 CONFIG_SYS_INIT_SP_OFFSET
390 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
391 pointer. This is needed for the temporary stack before
394 CONFIG_SYS_MIPS_CACHE_MODE
396 Cache operation mode for the MIPS CPU.
397 See also arch/mips/include/asm/mipsregs.h.
399 CONF_CM_CACHABLE_NO_WA
402 CONF_CM_CACHABLE_NONCOHERENT
406 CONF_CM_CACHABLE_ACCELERATED
408 CONFIG_SYS_XWAY_EBU_BOOTCFG
410 Special option for Lantiq XWAY SoCs for booting from NOR flash.
411 See also arch/mips/cpu/mips32/start.S.
413 CONFIG_XWAY_SWAP_BYTES
415 Enable compilation of tools/xway-swap-bytes needed for Lantiq
416 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
417 be swapped if a flash programmer is used.
419 - Linux Kernel Interface:
422 U-Boot stores all clock information in Hz
423 internally. For binary compatibility with older Linux
424 kernels (which expect the clocks passed in the
425 bd_info data to be in MHz) the environment variable
426 "clocks_in_mhz" can be defined so that U-Boot
427 converts clock data to MHZ before passing it to the
429 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
430 "clocks_in_mhz=1" is automatically included in the
433 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
435 When transferring memsize parameter to linux, some versions
436 expect it to be in bytes, others in MB.
437 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
441 New kernel versions are expecting firmware settings to be
442 passed using flattened device trees (based on open firmware
446 * New libfdt-based support
447 * Adds the "fdt" command
448 * The bootm command automatically updates the fdt
450 OF_CPU - The proper name of the cpus node (only required for
451 MPC512X and MPC5xxx based boards).
452 OF_SOC - The proper name of the soc node (only required for
453 MPC512X and MPC5xxx based boards).
454 OF_TBCLK - The timebase frequency.
455 OF_STDOUT_PATH - The path to the console device
457 boards with QUICC Engines require OF_QE to set UCC MAC
460 CONFIG_OF_BOARD_SETUP
462 Board code has addition modification that it wants to make
463 to the flat device tree before handing it off to the kernel
467 This define fills in the correct boot CPU in the boot
468 param header, the default value is zero if undefined.
472 U-Boot can detect if an IDE device is present or not.
473 If not, and this new config option is activated, U-Boot
474 removes the ATA node from the DTS before booting Linux,
475 so the Linux IDE driver does not probe the device and
476 crash. This is needed for buggy hardware (uc101) where
477 no pull down resistor is connected to the signal IDE5V_DD7.
479 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
481 This setting is mandatory for all boards that have only one
482 machine type and must be used to specify the machine type
483 number as it appears in the ARM machine registry
484 (see http://www.arm.linux.org.uk/developer/machines/).
485 Only boards that have multiple machine types supported
486 in a single configuration file and the machine type is
487 runtime discoverable, do not have to use this setting.
489 - vxWorks boot parameters:
491 bootvx constructs a valid bootline using the following
492 environments variables: bootfile, ipaddr, serverip, hostname.
493 It loads the vxWorks image pointed bootfile.
495 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
496 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
497 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
498 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
500 CONFIG_SYS_VXWORKS_ADD_PARAMS
502 Add it at the end of the bootline. E.g "u=username pw=secret"
504 Note: If a "bootargs" environment is defined, it will overwride
505 the defaults discussed just above.
507 - Cache Configuration:
508 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
509 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
510 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
512 - Cache Configuration for ARM:
513 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
515 CONFIG_SYS_PL310_BASE - Physical base address of PL310
516 controller register space
521 Define this if you want support for Amba PrimeCell PL010 UARTs.
525 Define this if you want support for Amba PrimeCell PL011 UARTs.
529 If you have Amba PrimeCell PL011 UARTs, set this variable to
530 the clock speed of the UARTs.
534 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
535 define this to a list of base addresses for each (supported)
536 port. See e.g. include/configs/versatile.h
538 CONFIG_PL011_SERIAL_RLCR
540 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
541 have separate receive and transmit line control registers. Set
542 this variable to initialize the extra register.
544 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
546 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
547 boot loader that has already initialized the UART. Define this
548 variable to flush the UART at init time.
552 Depending on board, define exactly one serial port
553 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
554 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
555 console by defining CONFIG_8xx_CONS_NONE
557 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
558 port routines must be defined elsewhere
559 (i.e. serial_init(), serial_getc(), ...)
562 Enables console device for a color framebuffer. Needs following
563 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
564 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
566 VIDEO_HW_RECTFILL graphic chip supports
569 VIDEO_HW_BITBLT graphic chip supports
570 bit-blit (cf. smiLynxEM)
571 VIDEO_VISIBLE_COLS visible pixel columns
573 VIDEO_VISIBLE_ROWS visible pixel rows
574 VIDEO_PIXEL_SIZE bytes per pixel
575 VIDEO_DATA_FORMAT graphic data format
576 (0-5, cf. cfb_console.c)
577 VIDEO_FB_ADRS framebuffer address
578 VIDEO_KBD_INIT_FCT keyboard int fct
579 (i.e. i8042_kbd_init())
580 VIDEO_TSTC_FCT test char fct
582 VIDEO_GETC_FCT get char fct
584 CONFIG_CONSOLE_CURSOR cursor drawing on/off
585 (requires blink timer
587 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
588 CONFIG_CONSOLE_TIME display time/date info in
590 (requires CONFIG_CMD_DATE)
591 CONFIG_VIDEO_LOGO display Linux logo in
593 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
594 linux_logo.h for logo.
595 Requires CONFIG_VIDEO_LOGO
596 CONFIG_CONSOLE_EXTRA_INFO
597 additional board info beside
600 When CONFIG_CFB_CONSOLE is defined, video console is
601 default i/o. Serial console can be forced with
602 environment 'console=serial'.
604 When CONFIG_SILENT_CONSOLE is defined, all console
605 messages (by U-Boot and Linux!) can be silenced with
606 the "silent" environment variable. See
607 doc/README.silent for more information.
610 CONFIG_BAUDRATE - in bps
611 Select one of the baudrates listed in
612 CONFIG_SYS_BAUDRATE_TABLE, see below.
613 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
615 - Console Rx buffer length
616 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
617 the maximum receive buffer length for the SMC.
618 This option is actual only for 82xx and 8xx possible.
619 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
620 must be defined, to setup the maximum idle timeout for
623 - Pre-Console Buffer:
624 Prior to the console being initialised (i.e. serial UART
625 initialised etc) all console output is silently discarded.
626 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
627 buffer any console messages prior to the console being
628 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
629 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
630 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
631 bytes are output before the console is initialised, the
632 earlier bytes are discarded.
634 'Sane' compilers will generate smaller code if
635 CONFIG_PRE_CON_BUF_SZ is a power of 2
637 - Boot Delay: CONFIG_BOOTDELAY - in seconds
638 Delay before automatically booting the default image;
639 set to -1 to disable autoboot.
641 See doc/README.autoboot for these options that
642 work with CONFIG_BOOTDELAY. None are required.
643 CONFIG_BOOT_RETRY_TIME
644 CONFIG_BOOT_RETRY_MIN
645 CONFIG_AUTOBOOT_KEYED
646 CONFIG_AUTOBOOT_PROMPT
647 CONFIG_AUTOBOOT_DELAY_STR
648 CONFIG_AUTOBOOT_STOP_STR
649 CONFIG_AUTOBOOT_DELAY_STR2
650 CONFIG_AUTOBOOT_STOP_STR2
651 CONFIG_ZERO_BOOTDELAY_CHECK
652 CONFIG_RESET_TO_RETRY
656 Only needed when CONFIG_BOOTDELAY is enabled;
657 define a command string that is automatically executed
658 when no character is read on the console interface
659 within "Boot Delay" after reset.
662 This can be used to pass arguments to the bootm
663 command. The value of CONFIG_BOOTARGS goes into the
664 environment value "bootargs".
666 CONFIG_RAMBOOT and CONFIG_NFSBOOT
667 The value of these goes into the environment as
668 "ramboot" and "nfsboot" respectively, and can be used
669 as a convenience, when switching between booting from
675 When this option is #defined, the existence of the
676 environment variable "preboot" will be checked
677 immediately before starting the CONFIG_BOOTDELAY
678 countdown and/or running the auto-boot command resp.
679 entering interactive mode.
681 This feature is especially useful when "preboot" is
682 automatically generated or modified. For an example
683 see the LWMON board specific code: here "preboot" is
684 modified when the user holds down a certain
685 combination of keys on the (special) keyboard when
688 - Serial Download Echo Mode:
690 If defined to 1, all characters received during a
691 serial download (using the "loads" command) are
692 echoed back. This might be needed by some terminal
693 emulations (like "cu"), but may as well just take
694 time on others. This setting #define's the initial
695 value of the "loads_echo" environment variable.
697 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
699 Select one of the baudrates listed in
700 CONFIG_SYS_BAUDRATE_TABLE, see below.
703 Monitor commands can be included or excluded
704 from the build by using the #include files
705 "config_cmd_all.h" and #undef'ing unwanted
706 commands, or using "config_cmd_default.h"
707 and augmenting with additional #define's
710 The default command configuration includes all commands
711 except those marked below with a "*".
713 CONFIG_CMD_ASKENV * ask for env variable
714 CONFIG_CMD_BDI bdinfo
715 CONFIG_CMD_BEDBUG * Include BedBug Debugger
716 CONFIG_CMD_BMP * BMP support
717 CONFIG_CMD_BSP * Board specific commands
718 CONFIG_CMD_BOOTD bootd
719 CONFIG_CMD_CACHE * icache, dcache
720 CONFIG_CMD_CONSOLE coninfo
721 CONFIG_CMD_CRC32 * crc32
722 CONFIG_CMD_DATE * support for RTC, date/time...
723 CONFIG_CMD_DHCP * DHCP support
724 CONFIG_CMD_DIAG * Diagnostics
725 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
726 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
727 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
728 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
729 CONFIG_CMD_DTT * Digital Therm and Thermostat
730 CONFIG_CMD_ECHO echo arguments
731 CONFIG_CMD_EDITENV edit env variable
732 CONFIG_CMD_EEPROM * EEPROM read/write support
733 CONFIG_CMD_ELF * bootelf, bootvx
734 CONFIG_CMD_EXPORTENV * export the environment
735 CONFIG_CMD_SAVEENV saveenv
736 CONFIG_CMD_FDC * Floppy Disk Support
737 CONFIG_CMD_FAT * FAT partition support
738 CONFIG_CMD_FDOS * Dos diskette Support
739 CONFIG_CMD_FLASH flinfo, erase, protect
740 CONFIG_CMD_FPGA FPGA device initialization support
741 CONFIG_CMD_GO * the 'go' command (exec code)
742 CONFIG_CMD_GREPENV * search environment
743 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
744 CONFIG_CMD_I2C * I2C serial bus support
745 CONFIG_CMD_IDE * IDE harddisk support
746 CONFIG_CMD_IMI iminfo
747 CONFIG_CMD_IMLS List all found images
748 CONFIG_CMD_IMMAP * IMMR dump support
749 CONFIG_CMD_IMPORTENV * import an environment
750 CONFIG_CMD_IRQ * irqinfo
751 CONFIG_CMD_ITEST Integer/string test of 2 values
752 CONFIG_CMD_JFFS2 * JFFS2 Support
753 CONFIG_CMD_KGDB * kgdb
754 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
755 CONFIG_CMD_LOADB loadb
756 CONFIG_CMD_LOADS loads
757 CONFIG_CMD_MD5SUM print md5 message digest
758 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
759 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
761 CONFIG_CMD_MISC Misc functions like sleep etc
762 CONFIG_CMD_MMC * MMC memory mapped support
763 CONFIG_CMD_MII * MII utility commands
764 CONFIG_CMD_MTDPARTS * MTD partition support
765 CONFIG_CMD_NAND * NAND support
766 CONFIG_CMD_NET bootp, tftpboot, rarpboot
767 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
768 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
769 CONFIG_CMD_PCI * pciinfo
770 CONFIG_CMD_PCMCIA * PCMCIA support
771 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
773 CONFIG_CMD_PORTIO * Port I/O
774 CONFIG_CMD_REGINFO * Register dump
775 CONFIG_CMD_RUN run command in env variable
776 CONFIG_CMD_SAVES * save S record dump
777 CONFIG_CMD_SCSI * SCSI Support
778 CONFIG_CMD_SDRAM * print SDRAM configuration information
779 (requires CONFIG_CMD_I2C)
780 CONFIG_CMD_SETGETDCR Support for DCR Register access
782 CONFIG_CMD_SHA1SUM print sha1 memory digest
783 (requires CONFIG_CMD_MEMORY)
784 CONFIG_CMD_SOURCE "source" command Support
785 CONFIG_CMD_SPI * SPI serial bus support
786 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
787 CONFIG_CMD_TIME * run command and report execution time
788 CONFIG_CMD_USB * USB support
789 CONFIG_CMD_CDP * Cisco Discover Protocol support
790 CONFIG_CMD_FSL * Microblaze FSL support
793 EXAMPLE: If you want all functions except of network
794 support you can write:
796 #include "config_cmd_all.h"
797 #undef CONFIG_CMD_NET
800 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
802 Note: Don't enable the "icache" and "dcache" commands
803 (configuration option CONFIG_CMD_CACHE) unless you know
804 what you (and your U-Boot users) are doing. Data
805 cache cannot be enabled on systems like the 8xx or
806 8260 (where accesses to the IMMR region must be
807 uncached), and it cannot be disabled on all other
808 systems where we (mis-) use the data cache to hold an
809 initial stack and some data.
812 XXX - this list needs to get updated!
816 If this variable is defined, it enables watchdog
817 support for the SoC. There must be support in the SoC
818 specific code for a watchdog. For the 8xx and 8260
819 CPUs, the SIU Watchdog feature is enabled in the SYPCR
820 register. When supported for a specific SoC is
821 available, then no further board specific code should
825 When using a watchdog circuitry external to the used
826 SoC, then define this variable and provide board
827 specific code for the "hw_watchdog_reset" function.
830 CONFIG_VERSION_VARIABLE
831 If this variable is defined, an environment variable
832 named "ver" is created by U-Boot showing the U-Boot
833 version as printed by the "version" command.
834 This variable is readonly.
838 When CONFIG_CMD_DATE is selected, the type of the RTC
839 has to be selected, too. Define exactly one of the
842 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
843 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
844 CONFIG_RTC_MC13783 - use MC13783 RTC
845 CONFIG_RTC_MC146818 - use MC146818 RTC
846 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
847 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
848 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
849 CONFIG_RTC_DS164x - use Dallas DS164x RTC
850 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
851 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
852 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
853 CONFIG_SYS_RV3029_TCR - enable trickle charger on
856 Note that if the RTC uses I2C, then the I2C interface
857 must also be configured. See I2C Support, below.
860 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
861 CONFIG_PCA953X_INFO - enable pca953x info command
863 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
864 chip-ngpio pairs that tell the PCA953X driver the number of
865 pins supported by a particular chip.
867 Note that if the GPIO device uses I2C, then the I2C interface
868 must also be configured. See I2C Support, below.
872 When CONFIG_TIMESTAMP is selected, the timestamp
873 (date and time) of an image is printed by image
874 commands like bootm or iminfo. This option is
875 automatically enabled when you select CONFIG_CMD_DATE .
878 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
879 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
881 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
882 CONFIG_CMD_SCSI) you must configure support for at
883 least one partition type as well.
886 CONFIG_IDE_RESET_ROUTINE - this is defined in several
887 board configurations files but used nowhere!
889 CONFIG_IDE_RESET - is this is defined, IDE Reset will
890 be performed by calling the function
891 ide_set_reset(int reset)
892 which has to be defined in a board specific file
897 Set this to enable ATAPI support.
902 Set this to enable support for disks larger than 137GB
903 Also look at CONFIG_SYS_64BIT_LBA.
904 Whithout these , LBA48 support uses 32bit variables and will 'only'
905 support disks up to 2.1TB.
907 CONFIG_SYS_64BIT_LBA:
908 When enabled, makes the IDE subsystem use 64bit sector addresses.
912 At the moment only there is only support for the
913 SYM53C8XX SCSI controller; define
914 CONFIG_SCSI_SYM53C8XX to enable it.
916 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
917 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
918 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
919 maximum numbers of LUNs, SCSI ID's and target
921 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
923 - NETWORK Support (PCI):
925 Support for Intel 8254x gigabit chips.
927 CONFIG_E1000_FALLBACK_MAC
928 default MAC for empty EEPROM after production.
931 Support for Intel 82557/82559/82559ER chips.
932 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
933 write routine for first time initialisation.
936 Support for Digital 2114x chips.
937 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
938 modem chip initialisation (KS8761/QS6611).
941 Support for National dp83815 chips.
944 Support for National dp8382[01] gigabit chips.
946 - NETWORK Support (other):
948 CONFIG_DRIVER_AT91EMAC
949 Support for AT91RM9200 EMAC.
952 Define this to use reduced MII inteface
954 CONFIG_DRIVER_AT91EMAC_QUIET
955 If this defined, the driver is quiet.
956 The driver doen't show link status messages.
958 CONFIG_DRIVER_LAN91C96
959 Support for SMSC's LAN91C96 chips.
962 Define this to hold the physical address
963 of the LAN91C96's I/O space
965 CONFIG_LAN91C96_USE_32_BIT
966 Define this to enable 32 bit addressing
968 CONFIG_DRIVER_SMC91111
969 Support for SMSC's LAN91C111 chip
972 Define this to hold the physical address
973 of the device (I/O space)
975 CONFIG_SMC_USE_32_BIT
976 Define this if data bus is 32 bits
978 CONFIG_SMC_USE_IOFUNCS
979 Define this to use i/o functions instead of macros
980 (some hardware wont work with macros)
983 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
985 CONFIG_FTGMAC100_EGIGA
986 Define this to use GE link update with gigabit PHY.
987 Define this if FTGMAC100 is connected to gigabit PHY.
988 If your system has 10/100 PHY only, it might not occur
989 wrong behavior. Because PHY usually return timeout or
990 useless data when polling gigabit status and gigabit
991 control registers. This behavior won't affect the
992 correctnessof 10/100 link speed update.
995 Support for SMSC's LAN911x and LAN921x chips
998 Define this to hold the physical address
999 of the device (I/O space)
1001 CONFIG_SMC911X_32_BIT
1002 Define this if data bus is 32 bits
1004 CONFIG_SMC911X_16_BIT
1005 Define this if data bus is 16 bits. If your processor
1006 automatically converts one 32 bit word to two 16 bit
1007 words you may also try CONFIG_SMC911X_32_BIT.
1010 Support for Renesas on-chip Ethernet controller
1012 CONFIG_SH_ETHER_USE_PORT
1013 Define the number of ports to be used
1015 CONFIG_SH_ETHER_PHY_ADDR
1016 Define the ETH PHY's address
1018 CONFIG_SH_ETHER_CACHE_WRITEBACK
1019 If this option is set, the driver enables cache flush.
1022 At the moment only the UHCI host controller is
1023 supported (PIP405, MIP405, MPC5200); define
1024 CONFIG_USB_UHCI to enable it.
1025 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1026 and define CONFIG_USB_STORAGE to enable the USB
1029 Supported are USB Keyboards and USB Floppy drives
1031 MPC5200 USB requires additional defines:
1033 for 528 MHz Clock: 0x0001bbbb
1037 for differential drivers: 0x00001000
1038 for single ended drivers: 0x00005000
1039 for differential drivers on PSC3: 0x00000100
1040 for single ended drivers on PSC3: 0x00004100
1041 CONFIG_SYS_USB_EVENT_POLL
1042 May be defined to allow interrupt polling
1043 instead of using asynchronous interrupts
1046 Define the below if you wish to use the USB console.
1047 Once firmware is rebuilt from a serial console issue the
1048 command "setenv stdin usbtty; setenv stdout usbtty" and
1049 attach your USB cable. The Unix command "dmesg" should print
1050 it has found a new device. The environment variable usbtty
1051 can be set to gserial or cdc_acm to enable your device to
1052 appear to a USB host as a Linux gserial device or a
1053 Common Device Class Abstract Control Model serial device.
1054 If you select usbtty = gserial you should be able to enumerate
1056 # modprobe usbserial vendor=0xVendorID product=0xProductID
1057 else if using cdc_acm, simply setting the environment
1058 variable usbtty to be cdc_acm should suffice. The following
1059 might be defined in YourBoardName.h
1062 Define this to build a UDC device
1065 Define this to have a tty type of device available to
1066 talk to the UDC device
1068 CONFIG_SYS_CONSOLE_IS_IN_ENV
1069 Define this if you want stdin, stdout &/or stderr to
1073 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1074 Derive USB clock from external clock "blah"
1075 - CONFIG_SYS_USB_EXTC_CLK 0x02
1077 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1078 Derive USB clock from brgclk
1079 - CONFIG_SYS_USB_BRG_CLK 0x04
1081 If you have a USB-IF assigned VendorID then you may wish to
1082 define your own vendor specific values either in BoardName.h
1083 or directly in usbd_vendor_info.h. If you don't define
1084 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1085 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1086 should pretend to be a Linux device to it's target host.
1088 CONFIG_USBD_MANUFACTURER
1089 Define this string as the name of your company for
1090 - CONFIG_USBD_MANUFACTURER "my company"
1092 CONFIG_USBD_PRODUCT_NAME
1093 Define this string as the name of your product
1094 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1096 CONFIG_USBD_VENDORID
1097 Define this as your assigned Vendor ID from the USB
1098 Implementors Forum. This *must* be a genuine Vendor ID
1099 to avoid polluting the USB namespace.
1100 - CONFIG_USBD_VENDORID 0xFFFF
1102 CONFIG_USBD_PRODUCTID
1103 Define this as the unique Product ID
1105 - CONFIG_USBD_PRODUCTID 0xFFFF
1109 The MMC controller on the Intel PXA is supported. To
1110 enable this define CONFIG_MMC. The MMC can be
1111 accessed from the boot prompt by mapping the device
1112 to physical memory similar to flash. Command line is
1113 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1114 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1117 Support for Renesas on-chip MMCIF controller
1119 CONFIG_SH_MMCIF_ADDR
1120 Define the base address of MMCIF registers
1123 Define the clock frequency for MMCIF
1125 - Journaling Flash filesystem support:
1126 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1127 CONFIG_JFFS2_NAND_DEV
1128 Define these for a default partition on a NAND device
1130 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1131 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1132 Define these for a default partition on a NOR device
1134 CONFIG_SYS_JFFS_CUSTOM_PART
1135 Define this to create an own partition. You have to provide a
1136 function struct part_info* jffs2_part_info(int part_num)
1138 If you define only one JFFS2 partition you may also want to
1139 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1140 to disable the command chpart. This is the default when you
1141 have not defined a custom partition
1146 Define this to enable standard (PC-Style) keyboard
1150 Standard PC keyboard driver with US (is default) and
1151 GERMAN key layout (switch via environment 'keymap=de') support.
1152 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1153 for cfb_console. Supports cursor blinking.
1158 Define this to enable video support (for output to
1161 CONFIG_VIDEO_CT69000
1163 Enable Chips & Technologies 69000 Video chip
1165 CONFIG_VIDEO_SMI_LYNXEM
1166 Enable Silicon Motion SMI 712/710/810 Video chip. The
1167 video output is selected via environment 'videoout'
1168 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1171 For the CT69000 and SMI_LYNXEM drivers, videomode is
1172 selected via environment 'videomode'. Two different ways
1174 - "videomode=num" 'num' is a standard LiLo mode numbers.
1175 Following standard modes are supported (* is default):
1177 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1178 -------------+---------------------------------------------
1179 8 bits | 0x301* 0x303 0x305 0x161 0x307
1180 15 bits | 0x310 0x313 0x316 0x162 0x319
1181 16 bits | 0x311 0x314 0x317 0x163 0x31A
1182 24 bits | 0x312 0x315 0x318 ? 0x31B
1183 -------------+---------------------------------------------
1184 (i.e. setenv videomode 317; saveenv; reset;)
1186 - "videomode=bootargs" all the video parameters are parsed
1187 from the bootargs. (See drivers/video/videomodes.c)
1190 CONFIG_VIDEO_SED13806
1191 Enable Epson SED13806 driver. This driver supports 8bpp
1192 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1193 or CONFIG_VIDEO_SED13806_16BPP
1196 Enable the Freescale DIU video driver. Reference boards for
1197 SOCs that have a DIU should define this macro to enable DIU
1198 support, and should also define these other macros:
1204 CONFIG_VIDEO_SW_CURSOR
1205 CONFIG_VGA_AS_SINGLE_DEVICE
1207 CONFIG_VIDEO_BMP_LOGO
1209 The DIU driver will look for the 'video-mode' environment
1210 variable, and if defined, enable the DIU as a console during
1211 boot. See the documentation file README.video for a
1212 description of this variable.
1217 Define this to enable a custom keyboard support.
1218 This simply calls drv_keyboard_init() which must be
1219 defined in your board-specific files.
1220 The only board using this so far is RBC823.
1222 - LCD Support: CONFIG_LCD
1224 Define this to enable LCD support (for output to LCD
1225 display); also select one of the supported displays
1226 by defining one of these:
1230 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1232 CONFIG_NEC_NL6448AC33:
1234 NEC NL6448AC33-18. Active, color, single scan.
1236 CONFIG_NEC_NL6448BC20
1238 NEC NL6448BC20-08. 6.5", 640x480.
1239 Active, color, single scan.
1241 CONFIG_NEC_NL6448BC33_54
1243 NEC NL6448BC33-54. 10.4", 640x480.
1244 Active, color, single scan.
1248 Sharp 320x240. Active, color, single scan.
1249 It isn't 16x9, and I am not sure what it is.
1251 CONFIG_SHARP_LQ64D341
1253 Sharp LQ64D341 display, 640x480.
1254 Active, color, single scan.
1258 HLD1045 display, 640x480.
1259 Active, color, single scan.
1263 Optrex CBL50840-2 NF-FW 99 22 M5
1265 Hitachi LMG6912RPFC-00T
1269 320x240. Black & white.
1271 Normally display is black on white background; define
1272 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1274 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1276 If this option is set, the environment is checked for
1277 a variable "splashimage". If found, the usual display
1278 of logo, copyright and system information on the LCD
1279 is suppressed and the BMP image at the address
1280 specified in "splashimage" is loaded instead. The
1281 console is redirected to the "nulldev", too. This
1282 allows for a "silent" boot where a splash screen is
1283 loaded very quickly after power-on.
1285 CONFIG_SPLASH_SCREEN_ALIGN
1287 If this option is set the splash image can be freely positioned
1288 on the screen. Environment variable "splashpos" specifies the
1289 position as "x,y". If a positive number is given it is used as
1290 number of pixel from left/top. If a negative number is given it
1291 is used as number of pixel from right/bottom. You can also
1292 specify 'm' for centering the image.
1295 setenv splashpos m,m
1296 => image at center of screen
1298 setenv splashpos 30,20
1299 => image at x = 30 and y = 20
1301 setenv splashpos -10,m
1302 => vertically centered image
1303 at x = dspWidth - bmpWidth - 9
1305 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1307 If this option is set, additionally to standard BMP
1308 images, gzipped BMP images can be displayed via the
1309 splashscreen support or the bmp command.
1311 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1313 If this option is set, 8-bit RLE compressed BMP images
1314 can be displayed via the splashscreen support or the
1317 - Compression support:
1320 If this option is set, support for bzip2 compressed
1321 images is included. If not, only uncompressed and gzip
1322 compressed images are supported.
1324 NOTE: the bzip2 algorithm requires a lot of RAM, so
1325 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1330 If this option is set, support for lzma compressed
1333 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1334 requires an amount of dynamic memory that is given by the
1337 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1339 Where lc and lp stand for, respectively, Literal context bits
1340 and Literal pos bits.
1342 This value is upper-bounded by 14MB in the worst case. Anyway,
1343 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1344 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1345 a very small buffer.
1347 Use the lzmainfo tool to determinate the lc and lp values and
1348 then calculate the amount of needed dynamic memory (ensuring
1349 the appropriate CONFIG_SYS_MALLOC_LEN value).
1354 The address of PHY on MII bus.
1356 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1358 The clock frequency of the MII bus
1362 If this option is set, support for speed/duplex
1363 detection of gigabit PHY is included.
1365 CONFIG_PHY_RESET_DELAY
1367 Some PHY like Intel LXT971A need extra delay after
1368 reset before any MII register access is possible.
1369 For such PHY, set this option to the usec delay
1370 required. (minimum 300usec for LXT971A)
1372 CONFIG_PHY_CMD_DELAY (ppc4xx)
1374 Some PHY like Intel LXT971A need extra delay after
1375 command issued before MII status register can be read
1385 Define a default value for Ethernet address to use
1386 for the respective Ethernet interface, in case this
1387 is not determined automatically.
1392 Define a default value for the IP address to use for
1393 the default Ethernet interface, in case this is not
1394 determined through e.g. bootp.
1396 - Server IP address:
1399 Defines a default value for the IP address of a TFTP
1400 server to contact when using the "tftboot" command.
1402 CONFIG_KEEP_SERVERADDR
1404 Keeps the server's MAC address, in the env 'serveraddr'
1405 for passing to bootargs (like Linux's netconsole option)
1407 - Multicast TFTP Mode:
1410 Defines whether you want to support multicast TFTP as per
1411 rfc-2090; for example to work with atftp. Lets lots of targets
1412 tftp down the same boot image concurrently. Note: the Ethernet
1413 driver in use must provide a function: mcast() to join/leave a
1416 - BOOTP Recovery Mode:
1417 CONFIG_BOOTP_RANDOM_DELAY
1419 If you have many targets in a network that try to
1420 boot using BOOTP, you may want to avoid that all
1421 systems send out BOOTP requests at precisely the same
1422 moment (which would happen for instance at recovery
1423 from a power failure, when all systems will try to
1424 boot, thus flooding the BOOTP server. Defining
1425 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1426 inserted before sending out BOOTP requests. The
1427 following delays are inserted then:
1429 1st BOOTP request: delay 0 ... 1 sec
1430 2nd BOOTP request: delay 0 ... 2 sec
1431 3rd BOOTP request: delay 0 ... 4 sec
1433 BOOTP requests: delay 0 ... 8 sec
1435 - DHCP Advanced Options:
1436 You can fine tune the DHCP functionality by defining
1437 CONFIG_BOOTP_* symbols:
1439 CONFIG_BOOTP_SUBNETMASK
1440 CONFIG_BOOTP_GATEWAY
1441 CONFIG_BOOTP_HOSTNAME
1442 CONFIG_BOOTP_NISDOMAIN
1443 CONFIG_BOOTP_BOOTPATH
1444 CONFIG_BOOTP_BOOTFILESIZE
1447 CONFIG_BOOTP_SEND_HOSTNAME
1448 CONFIG_BOOTP_NTPSERVER
1449 CONFIG_BOOTP_TIMEOFFSET
1450 CONFIG_BOOTP_VENDOREX
1452 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1453 environment variable, not the BOOTP server.
1455 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1456 serverip from a DHCP server, it is possible that more
1457 than one DNS serverip is offered to the client.
1458 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1459 serverip will be stored in the additional environment
1460 variable "dnsip2". The first DNS serverip is always
1461 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1464 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1465 to do a dynamic update of a DNS server. To do this, they
1466 need the hostname of the DHCP requester.
1467 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1468 of the "hostname" environment variable is passed as
1469 option 12 to the DHCP server.
1471 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1473 A 32bit value in microseconds for a delay between
1474 receiving a "DHCP Offer" and sending the "DHCP Request".
1475 This fixes a problem with certain DHCP servers that don't
1476 respond 100% of the time to a "DHCP request". E.g. On an
1477 AT91RM9200 processor running at 180MHz, this delay needed
1478 to be *at least* 15,000 usec before a Windows Server 2003
1479 DHCP server would reply 100% of the time. I recommend at
1480 least 50,000 usec to be safe. The alternative is to hope
1481 that one of the retries will be successful but note that
1482 the DHCP timeout and retry process takes a longer than
1486 CONFIG_CDP_DEVICE_ID
1488 The device id used in CDP trigger frames.
1490 CONFIG_CDP_DEVICE_ID_PREFIX
1492 A two character string which is prefixed to the MAC address
1497 A printf format string which contains the ascii name of
1498 the port. Normally is set to "eth%d" which sets
1499 eth0 for the first Ethernet, eth1 for the second etc.
1501 CONFIG_CDP_CAPABILITIES
1503 A 32bit integer which indicates the device capabilities;
1504 0x00000010 for a normal host which does not forwards.
1508 An ascii string containing the version of the software.
1512 An ascii string containing the name of the platform.
1516 A 32bit integer sent on the trigger.
1518 CONFIG_CDP_POWER_CONSUMPTION
1520 A 16bit integer containing the power consumption of the
1521 device in .1 of milliwatts.
1523 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1525 A byte containing the id of the VLAN.
1527 - Status LED: CONFIG_STATUS_LED
1529 Several configurations allow to display the current
1530 status using a LED. For instance, the LED will blink
1531 fast while running U-Boot code, stop blinking as
1532 soon as a reply to a BOOTP request was received, and
1533 start blinking slow once the Linux kernel is running
1534 (supported by a status LED driver in the Linux
1535 kernel). Defining CONFIG_STATUS_LED enables this
1538 - CAN Support: CONFIG_CAN_DRIVER
1540 Defining CONFIG_CAN_DRIVER enables CAN driver support
1541 on those systems that support this (optional)
1542 feature, like the TQM8xxL modules.
1544 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1546 These enable I2C serial bus commands. Defining either of
1547 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1548 include the appropriate I2C driver for the selected CPU.
1550 This will allow you to use i2c commands at the u-boot
1551 command line (as long as you set CONFIG_CMD_I2C in
1552 CONFIG_COMMANDS) and communicate with i2c based realtime
1553 clock chips. See common/cmd_i2c.c for a description of the
1554 command line interface.
1556 CONFIG_HARD_I2C selects a hardware I2C controller.
1558 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1559 bit-banging) driver instead of CPM or similar hardware
1562 There are several other quantities that must also be
1563 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1565 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1566 to be the frequency (in Hz) at which you wish your i2c bus
1567 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1568 the CPU's i2c node address).
1570 Now, the u-boot i2c code for the mpc8xx
1571 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1572 and so its address should therefore be cleared to 0 (See,
1573 eg, MPC823e User's Manual p.16-473). So, set
1574 CONFIG_SYS_I2C_SLAVE to 0.
1576 CONFIG_SYS_I2C_INIT_MPC5XXX
1578 When a board is reset during an i2c bus transfer
1579 chips might think that the current transfer is still
1580 in progress. Reset the slave devices by sending start
1581 commands until the slave device responds.
1583 That's all that's required for CONFIG_HARD_I2C.
1585 If you use the software i2c interface (CONFIG_SOFT_I2C)
1586 then the following macros need to be defined (examples are
1587 from include/configs/lwmon.h):
1591 (Optional). Any commands necessary to enable the I2C
1592 controller or configure ports.
1594 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1598 (Only for MPC8260 CPU). The I/O port to use (the code
1599 assumes both bits are on the same port). Valid values
1600 are 0..3 for ports A..D.
1604 The code necessary to make the I2C data line active
1605 (driven). If the data line is open collector, this
1608 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1612 The code necessary to make the I2C data line tri-stated
1613 (inactive). If the data line is open collector, this
1616 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1620 Code that returns TRUE if the I2C data line is high,
1623 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1627 If <bit> is TRUE, sets the I2C data line high. If it
1628 is FALSE, it clears it (low).
1630 eg: #define I2C_SDA(bit) \
1631 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1632 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1636 If <bit> is TRUE, sets the I2C clock line high. If it
1637 is FALSE, it clears it (low).
1639 eg: #define I2C_SCL(bit) \
1640 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1641 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1645 This delay is invoked four times per clock cycle so this
1646 controls the rate of data transfer. The data rate thus
1647 is 1 / (I2C_DELAY * 4). Often defined to be something
1650 #define I2C_DELAY udelay(2)
1652 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1654 If your arch supports the generic GPIO framework (asm/gpio.h),
1655 then you may alternatively define the two GPIOs that are to be
1656 used as SCL / SDA. Any of the previous I2C_xxx macros will
1657 have GPIO-based defaults assigned to them as appropriate.
1659 You should define these to the GPIO value as given directly to
1660 the generic GPIO functions.
1662 CONFIG_SYS_I2C_INIT_BOARD
1664 When a board is reset during an i2c bus transfer
1665 chips might think that the current transfer is still
1666 in progress. On some boards it is possible to access
1667 the i2c SCLK line directly, either by using the
1668 processor pin as a GPIO or by having a second pin
1669 connected to the bus. If this option is defined a
1670 custom i2c_init_board() routine in boards/xxx/board.c
1671 is run early in the boot sequence.
1673 CONFIG_SYS_I2C_BOARD_LATE_INIT
1675 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1676 defined a custom i2c_board_late_init() routine in
1677 boards/xxx/board.c is run AFTER the operations in i2c_init()
1678 is completed. This callpoint can be used to unreset i2c bus
1679 using CPU i2c controller register accesses for CPUs whose i2c
1680 controller provide such a method. It is called at the end of
1681 i2c_init() to allow i2c_init operations to setup the i2c bus
1682 controller on the CPU (e.g. setting bus speed & slave address).
1684 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1686 This option enables configuration of bi_iic_fast[] flags
1687 in u-boot bd_info structure based on u-boot environment
1688 variable "i2cfast". (see also i2cfast)
1690 CONFIG_I2C_MULTI_BUS
1692 This option allows the use of multiple I2C buses, each of which
1693 must have a controller. At any point in time, only one bus is
1694 active. To switch to a different bus, use the 'i2c dev' command.
1695 Note that bus numbering is zero-based.
1697 CONFIG_SYS_I2C_NOPROBES
1699 This option specifies a list of I2C devices that will be skipped
1700 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1701 is set, specify a list of bus-device pairs. Otherwise, specify
1702 a 1D array of device addresses
1705 #undef CONFIG_I2C_MULTI_BUS
1706 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1708 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1710 #define CONFIG_I2C_MULTI_BUS
1711 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1713 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1715 CONFIG_SYS_SPD_BUS_NUM
1717 If defined, then this indicates the I2C bus number for DDR SPD.
1718 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1720 CONFIG_SYS_RTC_BUS_NUM
1722 If defined, then this indicates the I2C bus number for the RTC.
1723 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1725 CONFIG_SYS_DTT_BUS_NUM
1727 If defined, then this indicates the I2C bus number for the DTT.
1728 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1730 CONFIG_SYS_I2C_DTT_ADDR:
1732 If defined, specifies the I2C address of the DTT device.
1733 If not defined, then U-Boot uses predefined value for
1734 specified DTT device.
1738 Define this option if you want to use Freescale's I2C driver in
1739 drivers/i2c/fsl_i2c.c.
1743 Define this option if you have I2C devices reached over 1 .. n
1744 I2C Muxes like the pca9544a. This option addes a new I2C
1745 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1746 new I2C Bus to the existing I2C Busses. If you select the
1747 new Bus with "i2c dev", u-bbot sends first the commandos for
1748 the muxes to activate this new "bus".
1750 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1754 Adding a new I2C Bus reached over 2 pca9544a muxes
1755 The First mux with address 70 and channel 6
1756 The Second mux with address 71 and channel 4
1758 => i2c bus pca9544a:70:6:pca9544a:71:4
1760 Use the "i2c bus" command without parameter, to get a list
1761 of I2C Busses with muxes:
1764 Busses reached over muxes:
1766 reached over Mux(es):
1769 reached over Mux(es):
1774 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1775 u-boot first sends the command to the mux@70 to enable
1776 channel 6, and then the command to the mux@71 to enable
1779 After that, you can use the "normal" i2c commands as
1780 usual to communicate with your I2C devices behind
1783 This option is actually implemented for the bitbanging
1784 algorithm in common/soft_i2c.c and for the Hardware I2C
1785 Bus on the MPC8260. But it should be not so difficult
1786 to add this option to other architectures.
1788 CONFIG_SOFT_I2C_READ_REPEATED_START
1790 defining this will force the i2c_read() function in
1791 the soft_i2c driver to perform an I2C repeated start
1792 between writing the address pointer and reading the
1793 data. If this define is omitted the default behaviour
1794 of doing a stop-start sequence will be used. Most I2C
1795 devices can use either method, but some require one or
1798 - SPI Support: CONFIG_SPI
1800 Enables SPI driver (so far only tested with
1801 SPI EEPROM, also an instance works with Crystal A/D and
1802 D/As on the SACSng board)
1806 Enables the driver for SPI controller on SuperH. Currently
1807 only SH7757 is supported.
1811 Enables extended (16-bit) SPI EEPROM addressing.
1812 (symmetrical to CONFIG_I2C_X)
1816 Enables a software (bit-bang) SPI driver rather than
1817 using hardware support. This is a general purpose
1818 driver that only requires three general I/O port pins
1819 (two outputs, one input) to function. If this is
1820 defined, the board configuration must define several
1821 SPI configuration items (port pins to use, etc). For
1822 an example, see include/configs/sacsng.h.
1826 Enables a hardware SPI driver for general-purpose reads
1827 and writes. As with CONFIG_SOFT_SPI, the board configuration
1828 must define a list of chip-select function pointers.
1829 Currently supported on some MPC8xxx processors. For an
1830 example, see include/configs/mpc8349emds.h.
1834 Enables the driver for the SPI controllers on i.MX and MXC
1835 SoCs. Currently only i.MX31 is supported.
1837 - FPGA Support: CONFIG_FPGA
1839 Enables FPGA subsystem.
1841 CONFIG_FPGA_<vendor>
1843 Enables support for specific chip vendors.
1846 CONFIG_FPGA_<family>
1848 Enables support for FPGA family.
1849 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1853 Specify the number of FPGA devices to support.
1855 CONFIG_SYS_FPGA_PROG_FEEDBACK
1857 Enable printing of hash marks during FPGA configuration.
1859 CONFIG_SYS_FPGA_CHECK_BUSY
1861 Enable checks on FPGA configuration interface busy
1862 status by the configuration function. This option
1863 will require a board or device specific function to
1868 If defined, a function that provides delays in the FPGA
1869 configuration driver.
1871 CONFIG_SYS_FPGA_CHECK_CTRLC
1872 Allow Control-C to interrupt FPGA configuration
1874 CONFIG_SYS_FPGA_CHECK_ERROR
1876 Check for configuration errors during FPGA bitfile
1877 loading. For example, abort during Virtex II
1878 configuration if the INIT_B line goes low (which
1879 indicated a CRC error).
1881 CONFIG_SYS_FPGA_WAIT_INIT
1883 Maximum time to wait for the INIT_B line to deassert
1884 after PROB_B has been deasserted during a Virtex II
1885 FPGA configuration sequence. The default time is 500
1888 CONFIG_SYS_FPGA_WAIT_BUSY
1890 Maximum time to wait for BUSY to deassert during
1891 Virtex II FPGA configuration. The default is 5 ms.
1893 CONFIG_SYS_FPGA_WAIT_CONFIG
1895 Time to wait after FPGA configuration. The default is
1898 - Configuration Management:
1901 If defined, this string will be added to the U-Boot
1902 version information (U_BOOT_VERSION)
1904 - Vendor Parameter Protection:
1906 U-Boot considers the values of the environment
1907 variables "serial#" (Board Serial Number) and
1908 "ethaddr" (Ethernet Address) to be parameters that
1909 are set once by the board vendor / manufacturer, and
1910 protects these variables from casual modification by
1911 the user. Once set, these variables are read-only,
1912 and write or delete attempts are rejected. You can
1913 change this behaviour:
1915 If CONFIG_ENV_OVERWRITE is #defined in your config
1916 file, the write protection for vendor parameters is
1917 completely disabled. Anybody can change or delete
1920 Alternatively, if you #define _both_ CONFIG_ETHADDR
1921 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1922 Ethernet address is installed in the environment,
1923 which can be changed exactly ONCE by the user. [The
1924 serial# is unaffected by this, i. e. it remains
1930 Define this variable to enable the reservation of
1931 "protected RAM", i. e. RAM which is not overwritten
1932 by U-Boot. Define CONFIG_PRAM to hold the number of
1933 kB you want to reserve for pRAM. You can overwrite
1934 this default value by defining an environment
1935 variable "pram" to the number of kB you want to
1936 reserve. Note that the board info structure will
1937 still show the full amount of RAM. If pRAM is
1938 reserved, a new environment variable "mem" will
1939 automatically be defined to hold the amount of
1940 remaining RAM in a form that can be passed as boot
1941 argument to Linux, for instance like that:
1943 setenv bootargs ... mem=\${mem}
1946 This way you can tell Linux not to use this memory,
1947 either, which results in a memory region that will
1948 not be affected by reboots.
1950 *WARNING* If your board configuration uses automatic
1951 detection of the RAM size, you must make sure that
1952 this memory test is non-destructive. So far, the
1953 following board configurations are known to be
1956 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1957 HERMES, IP860, RPXlite, LWMON, LANTEC,
1963 Define this variable to stop the system in case of a
1964 fatal error, so that you have to reset it manually.
1965 This is probably NOT a good idea for an embedded
1966 system where you want the system to reboot
1967 automatically as fast as possible, but it may be
1968 useful during development since you can try to debug
1969 the conditions that lead to the situation.
1971 CONFIG_NET_RETRY_COUNT
1973 This variable defines the number of retries for
1974 network operations like ARP, RARP, TFTP, or BOOTP
1975 before giving up the operation. If not defined, a
1976 default value of 5 is used.
1980 Timeout waiting for an ARP reply in milliseconds.
1982 - Command Interpreter:
1983 CONFIG_AUTO_COMPLETE
1985 Enable auto completion of commands using TAB.
1987 Note that this feature has NOT been implemented yet
1988 for the "hush" shell.
1991 CONFIG_SYS_HUSH_PARSER
1993 Define this variable to enable the "hush" shell (from
1994 Busybox) as command line interpreter, thus enabling
1995 powerful command line syntax like
1996 if...then...else...fi conditionals or `&&' and '||'
1997 constructs ("shell scripts").
1999 If undefined, you get the old, much simpler behaviour
2000 with a somewhat smaller memory footprint.
2003 CONFIG_SYS_PROMPT_HUSH_PS2
2005 This defines the secondary prompt string, which is
2006 printed when the command interpreter needs more input
2007 to complete a command. Usually "> ".
2011 In the current implementation, the local variables
2012 space and global environment variables space are
2013 separated. Local variables are those you define by
2014 simply typing `name=value'. To access a local
2015 variable later on, you have write `$name' or
2016 `${name}'; to execute the contents of a variable
2017 directly type `$name' at the command prompt.
2019 Global environment variables are those you use
2020 setenv/printenv to work with. To run a command stored
2021 in such a variable, you need to use the run command,
2022 and you must not use the '$' sign to access them.
2024 To store commands and special characters in a
2025 variable, please use double quotation marks
2026 surrounding the whole text of the variable, instead
2027 of the backslashes before semicolons and special
2030 - Commandline Editing and History:
2031 CONFIG_CMDLINE_EDITING
2033 Enable editing and History functions for interactive
2034 commandline input operations
2036 - Default Environment:
2037 CONFIG_EXTRA_ENV_SETTINGS
2039 Define this to contain any number of null terminated
2040 strings (variable = value pairs) that will be part of
2041 the default environment compiled into the boot image.
2043 For example, place something like this in your
2044 board's config file:
2046 #define CONFIG_EXTRA_ENV_SETTINGS \
2050 Warning: This method is based on knowledge about the
2051 internal format how the environment is stored by the
2052 U-Boot code. This is NOT an official, exported
2053 interface! Although it is unlikely that this format
2054 will change soon, there is no guarantee either.
2055 You better know what you are doing here.
2057 Note: overly (ab)use of the default environment is
2058 discouraged. Make sure to check other ways to preset
2059 the environment like the "source" command or the
2062 - DataFlash Support:
2063 CONFIG_HAS_DATAFLASH
2065 Defining this option enables DataFlash features and
2066 allows to read/write in Dataflash via the standard
2069 - SystemACE Support:
2072 Adding this option adds support for Xilinx SystemACE
2073 chips attached via some sort of local bus. The address
2074 of the chip must also be defined in the
2075 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2077 #define CONFIG_SYSTEMACE
2078 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2080 When SystemACE support is added, the "ace" device type
2081 becomes available to the fat commands, i.e. fatls.
2083 - TFTP Fixed UDP Port:
2086 If this is defined, the environment variable tftpsrcp
2087 is used to supply the TFTP UDP source port value.
2088 If tftpsrcp isn't defined, the normal pseudo-random port
2089 number generator is used.
2091 Also, the environment variable tftpdstp is used to supply
2092 the TFTP UDP destination port value. If tftpdstp isn't
2093 defined, the normal port 69 is used.
2095 The purpose for tftpsrcp is to allow a TFTP server to
2096 blindly start the TFTP transfer using the pre-configured
2097 target IP address and UDP port. This has the effect of
2098 "punching through" the (Windows XP) firewall, allowing
2099 the remainder of the TFTP transfer to proceed normally.
2100 A better solution is to properly configure the firewall,
2101 but sometimes that is not allowed.
2103 - Show boot progress:
2104 CONFIG_SHOW_BOOT_PROGRESS
2106 Defining this option allows to add some board-
2107 specific code (calling a user-provided function
2108 "show_boot_progress(int)") that enables you to show
2109 the system's boot progress on some display (for
2110 example, some LED's) on your board. At the moment,
2111 the following checkpoints are implemented:
2113 Legacy uImage format:
2116 1 common/cmd_bootm.c before attempting to boot an image
2117 -1 common/cmd_bootm.c Image header has bad magic number
2118 2 common/cmd_bootm.c Image header has correct magic number
2119 -2 common/cmd_bootm.c Image header has bad checksum
2120 3 common/cmd_bootm.c Image header has correct checksum
2121 -3 common/cmd_bootm.c Image data has bad checksum
2122 4 common/cmd_bootm.c Image data has correct checksum
2123 -4 common/cmd_bootm.c Image is for unsupported architecture
2124 5 common/cmd_bootm.c Architecture check OK
2125 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2126 6 common/cmd_bootm.c Image Type check OK
2127 -6 common/cmd_bootm.c gunzip uncompression error
2128 -7 common/cmd_bootm.c Unimplemented compression type
2129 7 common/cmd_bootm.c Uncompression OK
2130 8 common/cmd_bootm.c No uncompress/copy overwrite error
2131 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2133 9 common/image.c Start initial ramdisk verification
2134 -10 common/image.c Ramdisk header has bad magic number
2135 -11 common/image.c Ramdisk header has bad checksum
2136 10 common/image.c Ramdisk header is OK
2137 -12 common/image.c Ramdisk data has bad checksum
2138 11 common/image.c Ramdisk data has correct checksum
2139 12 common/image.c Ramdisk verification complete, start loading
2140 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2141 13 common/image.c Start multifile image verification
2142 14 common/image.c No initial ramdisk, no multifile, continue.
2144 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2146 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2147 -31 post/post.c POST test failed, detected by post_output_backlog()
2148 -32 post/post.c POST test failed, detected by post_run_single()
2150 34 common/cmd_doc.c before loading a Image from a DOC device
2151 -35 common/cmd_doc.c Bad usage of "doc" command
2152 35 common/cmd_doc.c correct usage of "doc" command
2153 -36 common/cmd_doc.c No boot device
2154 36 common/cmd_doc.c correct boot device
2155 -37 common/cmd_doc.c Unknown Chip ID on boot device
2156 37 common/cmd_doc.c correct chip ID found, device available
2157 -38 common/cmd_doc.c Read Error on boot device
2158 38 common/cmd_doc.c reading Image header from DOC device OK
2159 -39 common/cmd_doc.c Image header has bad magic number
2160 39 common/cmd_doc.c Image header has correct magic number
2161 -40 common/cmd_doc.c Error reading Image from DOC device
2162 40 common/cmd_doc.c Image header has correct magic number
2163 41 common/cmd_ide.c before loading a Image from a IDE device
2164 -42 common/cmd_ide.c Bad usage of "ide" command
2165 42 common/cmd_ide.c correct usage of "ide" command
2166 -43 common/cmd_ide.c No boot device
2167 43 common/cmd_ide.c boot device found
2168 -44 common/cmd_ide.c Device not available
2169 44 common/cmd_ide.c Device available
2170 -45 common/cmd_ide.c wrong partition selected
2171 45 common/cmd_ide.c partition selected
2172 -46 common/cmd_ide.c Unknown partition table
2173 46 common/cmd_ide.c valid partition table found
2174 -47 common/cmd_ide.c Invalid partition type
2175 47 common/cmd_ide.c correct partition type
2176 -48 common/cmd_ide.c Error reading Image Header on boot device
2177 48 common/cmd_ide.c reading Image Header from IDE device OK
2178 -49 common/cmd_ide.c Image header has bad magic number
2179 49 common/cmd_ide.c Image header has correct magic number
2180 -50 common/cmd_ide.c Image header has bad checksum
2181 50 common/cmd_ide.c Image header has correct checksum
2182 -51 common/cmd_ide.c Error reading Image from IDE device
2183 51 common/cmd_ide.c reading Image from IDE device OK
2184 52 common/cmd_nand.c before loading a Image from a NAND device
2185 -53 common/cmd_nand.c Bad usage of "nand" command
2186 53 common/cmd_nand.c correct usage of "nand" command
2187 -54 common/cmd_nand.c No boot device
2188 54 common/cmd_nand.c boot device found
2189 -55 common/cmd_nand.c Unknown Chip ID on boot device
2190 55 common/cmd_nand.c correct chip ID found, device available
2191 -56 common/cmd_nand.c Error reading Image Header on boot device
2192 56 common/cmd_nand.c reading Image Header from NAND device OK
2193 -57 common/cmd_nand.c Image header has bad magic number
2194 57 common/cmd_nand.c Image header has correct magic number
2195 -58 common/cmd_nand.c Error reading Image from NAND device
2196 58 common/cmd_nand.c reading Image from NAND device OK
2198 -60 common/env_common.c Environment has a bad CRC, using default
2200 64 net/eth.c starting with Ethernet configuration.
2201 -64 net/eth.c no Ethernet found.
2202 65 net/eth.c Ethernet found.
2204 -80 common/cmd_net.c usage wrong
2205 80 common/cmd_net.c before calling NetLoop()
2206 -81 common/cmd_net.c some error in NetLoop() occurred
2207 81 common/cmd_net.c NetLoop() back without error
2208 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2209 82 common/cmd_net.c trying automatic boot
2210 83 common/cmd_net.c running "source" command
2211 -83 common/cmd_net.c some error in automatic boot or "source" command
2212 84 common/cmd_net.c end without errors
2217 100 common/cmd_bootm.c Kernel FIT Image has correct format
2218 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2219 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2220 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2221 102 common/cmd_bootm.c Kernel unit name specified
2222 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2223 103 common/cmd_bootm.c Found configuration node
2224 104 common/cmd_bootm.c Got kernel subimage node offset
2225 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2226 105 common/cmd_bootm.c Kernel subimage hash verification OK
2227 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2228 106 common/cmd_bootm.c Architecture check OK
2229 -106 common/cmd_bootm.c Kernel subimage has wrong type
2230 107 common/cmd_bootm.c Kernel subimage type OK
2231 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2232 108 common/cmd_bootm.c Got kernel subimage data/size
2233 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2234 -109 common/cmd_bootm.c Can't get kernel subimage type
2235 -110 common/cmd_bootm.c Can't get kernel subimage comp
2236 -111 common/cmd_bootm.c Can't get kernel subimage os
2237 -112 common/cmd_bootm.c Can't get kernel subimage load address
2238 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2240 120 common/image.c Start initial ramdisk verification
2241 -120 common/image.c Ramdisk FIT image has incorrect format
2242 121 common/image.c Ramdisk FIT image has correct format
2243 122 common/image.c No ramdisk subimage unit name, using configuration
2244 -122 common/image.c Can't get configuration for ramdisk subimage
2245 123 common/image.c Ramdisk unit name specified
2246 -124 common/image.c Can't get ramdisk subimage node offset
2247 125 common/image.c Got ramdisk subimage node offset
2248 -125 common/image.c Ramdisk subimage hash verification failed
2249 126 common/image.c Ramdisk subimage hash verification OK
2250 -126 common/image.c Ramdisk subimage for unsupported architecture
2251 127 common/image.c Architecture check OK
2252 -127 common/image.c Can't get ramdisk subimage data/size
2253 128 common/image.c Got ramdisk subimage data/size
2254 129 common/image.c Can't get ramdisk load address
2255 -129 common/image.c Got ramdisk load address
2257 -130 common/cmd_doc.c Incorrect FIT image format
2258 131 common/cmd_doc.c FIT image format OK
2260 -140 common/cmd_ide.c Incorrect FIT image format
2261 141 common/cmd_ide.c FIT image format OK
2263 -150 common/cmd_nand.c Incorrect FIT image format
2264 151 common/cmd_nand.c FIT image format OK
2266 - Standalone program support:
2267 CONFIG_STANDALONE_LOAD_ADDR
2269 This option defines a board specific value for the
2270 address where standalone program gets loaded, thus
2271 overwriting the architecture dependent default
2274 - Frame Buffer Address:
2277 Define CONFIG_FB_ADDR if you want to use specific
2278 address for frame buffer.
2279 Then system will reserve the frame buffer address to
2280 defined address instead of lcd_setmem (this function
2281 grabs the memory for frame buffer by panel's size).
2283 Please see board_init_f function.
2285 - Automatic software updates via TFTP server
2287 CONFIG_UPDATE_TFTP_CNT_MAX
2288 CONFIG_UPDATE_TFTP_MSEC_MAX
2290 These options enable and control the auto-update feature;
2291 for a more detailed description refer to doc/README.update.
2293 - MTD Support (mtdparts command, UBI support)
2296 Adds the MTD device infrastructure from the Linux kernel.
2297 Needed for mtdparts command support.
2299 CONFIG_MTD_PARTITIONS
2301 Adds the MTD partitioning infrastructure from the Linux
2302 kernel. Needed for UBI support.
2306 Enable building of SPL globally.
2308 CONFIG_SPL_TEXT_BASE
2309 TEXT_BASE for linking the SPL binary.
2312 LDSCRIPT for linking the SPL binary.
2314 CONFIG_SPL_LIBCOMMON_SUPPORT
2315 Support for common/libcommon.o in SPL binary
2317 CONFIG_SPL_LIBDISK_SUPPORT
2318 Support for disk/libdisk.o in SPL binary
2320 CONFIG_SPL_I2C_SUPPORT
2321 Support for drivers/i2c/libi2c.o in SPL binary
2323 CONFIG_SPL_GPIO_SUPPORT
2324 Support for drivers/gpio/libgpio.o in SPL binary
2326 CONFIG_SPL_MMC_SUPPORT
2327 Support for drivers/mmc/libmmc.o in SPL binary
2329 CONFIG_SPL_SERIAL_SUPPORT
2330 Support for drivers/serial/libserial.o in SPL binary
2332 CONFIG_SPL_SPI_FLASH_SUPPORT
2333 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2335 CONFIG_SPL_SPI_SUPPORT
2336 Support for drivers/spi/libspi.o in SPL binary
2338 CONFIG_SPL_FAT_SUPPORT
2339 Support for fs/fat/libfat.o in SPL binary
2341 CONFIG_SPL_LIBGENERIC_SUPPORT
2342 Support for lib/libgeneric.o in SPL binary
2347 [so far only for SMDK2400 boards]
2349 - Modem support enable:
2350 CONFIG_MODEM_SUPPORT
2352 - RTS/CTS Flow control enable:
2355 - Modem debug support:
2356 CONFIG_MODEM_SUPPORT_DEBUG
2358 Enables debugging stuff (char screen[1024], dbg())
2359 for modem support. Useful only with BDI2000.
2361 - Interrupt support (PPC):
2363 There are common interrupt_init() and timer_interrupt()
2364 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2365 for CPU specific initialization. interrupt_init_cpu()
2366 should set decrementer_count to appropriate value. If
2367 CPU resets decrementer automatically after interrupt
2368 (ppc4xx) it should set decrementer_count to zero.
2369 timer_interrupt() calls timer_interrupt_cpu() for CPU
2370 specific handling. If board has watchdog / status_led
2371 / other_activity_monitor it works automatically from
2372 general timer_interrupt().
2376 In the target system modem support is enabled when a
2377 specific key (key combination) is pressed during
2378 power-on. Otherwise U-Boot will boot normally
2379 (autoboot). The key_pressed() function is called from
2380 board_init(). Currently key_pressed() is a dummy
2381 function, returning 1 and thus enabling modem
2384 If there are no modem init strings in the
2385 environment, U-Boot proceed to autoboot; the
2386 previous output (banner, info printfs) will be
2389 See also: doc/README.Modem
2392 Configuration Settings:
2393 -----------------------
2395 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2396 undefine this when you're short of memory.
2398 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2399 width of the commands listed in the 'help' command output.
2401 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2402 prompt for user input.
2404 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2406 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2408 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2410 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2411 the application (usually a Linux kernel) when it is
2414 - CONFIG_SYS_BAUDRATE_TABLE:
2415 List of legal baudrate settings for this board.
2417 - CONFIG_SYS_CONSOLE_INFO_QUIET
2418 Suppress display of console information at boot.
2420 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2421 If the board specific function
2422 extern int overwrite_console (void);
2423 returns 1, the stdin, stderr and stdout are switched to the
2424 serial port, else the settings in the environment are used.
2426 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2427 Enable the call to overwrite_console().
2429 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2430 Enable overwrite of previous console environment settings.
2432 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2433 Begin and End addresses of the area used by the
2436 - CONFIG_SYS_ALT_MEMTEST:
2437 Enable an alternate, more extensive memory test.
2439 - CONFIG_SYS_MEMTEST_SCRATCH:
2440 Scratch address used by the alternate memory test
2441 You only need to set this if address zero isn't writeable
2443 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2444 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2445 this specified memory area will get subtracted from the top
2446 (end) of RAM and won't get "touched" at all by U-Boot. By
2447 fixing up gd->ram_size the Linux kernel should gets passed
2448 the now "corrected" memory size and won't touch it either.
2449 This should work for arch/ppc and arch/powerpc. Only Linux
2450 board ports in arch/powerpc with bootwrapper support that
2451 recalculate the memory size from the SDRAM controller setup
2452 will have to get fixed in Linux additionally.
2454 This option can be used as a workaround for the 440EPx/GRx
2455 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2458 WARNING: Please make sure that this value is a multiple of
2459 the Linux page size (normally 4k). If this is not the case,
2460 then the end address of the Linux memory will be located at a
2461 non page size aligned address and this could cause major
2464 - CONFIG_SYS_TFTP_LOADADDR:
2465 Default load address for network file downloads
2467 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2468 Enable temporary baudrate change while serial download
2470 - CONFIG_SYS_SDRAM_BASE:
2471 Physical start address of SDRAM. _Must_ be 0 here.
2473 - CONFIG_SYS_MBIO_BASE:
2474 Physical start address of Motherboard I/O (if using a
2477 - CONFIG_SYS_FLASH_BASE:
2478 Physical start address of Flash memory.
2480 - CONFIG_SYS_MONITOR_BASE:
2481 Physical start address of boot monitor code (set by
2482 make config files to be same as the text base address
2483 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2484 CONFIG_SYS_FLASH_BASE when booting from flash.
2486 - CONFIG_SYS_MONITOR_LEN:
2487 Size of memory reserved for monitor code, used to
2488 determine _at_compile_time_ (!) if the environment is
2489 embedded within the U-Boot image, or in a separate
2492 - CONFIG_SYS_MALLOC_LEN:
2493 Size of DRAM reserved for malloc() use.
2495 - CONFIG_SYS_BOOTM_LEN:
2496 Normally compressed uImages are limited to an
2497 uncompressed size of 8 MBytes. If this is not enough,
2498 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2499 to adjust this setting to your needs.
2501 - CONFIG_SYS_BOOTMAPSZ:
2502 Maximum size of memory mapped by the startup code of
2503 the Linux kernel; all data that must be processed by
2504 the Linux kernel (bd_info, boot arguments, FDT blob if
2505 used) must be put below this limit, unless "bootm_low"
2506 enviroment variable is defined and non-zero. In such case
2507 all data for the Linux kernel must be between "bootm_low"
2508 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2509 variable "bootm_mapsize" will override the value of
2510 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2511 then the value in "bootm_size" will be used instead.
2513 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2514 Enable initrd_high functionality. If defined then the
2515 initrd_high feature is enabled and the bootm ramdisk subcommand
2518 - CONFIG_SYS_BOOT_GET_CMDLINE:
2519 Enables allocating and saving kernel cmdline in space between
2520 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2522 - CONFIG_SYS_BOOT_GET_KBD:
2523 Enables allocating and saving a kernel copy of the bd_info in
2524 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2526 - CONFIG_SYS_MAX_FLASH_BANKS:
2527 Max number of Flash memory banks
2529 - CONFIG_SYS_MAX_FLASH_SECT:
2530 Max number of sectors on a Flash chip
2532 - CONFIG_SYS_FLASH_ERASE_TOUT:
2533 Timeout for Flash erase operations (in ms)
2535 - CONFIG_SYS_FLASH_WRITE_TOUT:
2536 Timeout for Flash write operations (in ms)
2538 - CONFIG_SYS_FLASH_LOCK_TOUT
2539 Timeout for Flash set sector lock bit operation (in ms)
2541 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2542 Timeout for Flash clear lock bits operation (in ms)
2544 - CONFIG_SYS_FLASH_PROTECTION
2545 If defined, hardware flash sectors protection is used
2546 instead of U-Boot software protection.
2548 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2550 Enable TFTP transfers directly to flash memory;
2551 without this option such a download has to be
2552 performed in two steps: (1) download to RAM, and (2)
2553 copy from RAM to flash.
2555 The two-step approach is usually more reliable, since
2556 you can check if the download worked before you erase
2557 the flash, but in some situations (when system RAM is
2558 too limited to allow for a temporary copy of the
2559 downloaded image) this option may be very useful.
2561 - CONFIG_SYS_FLASH_CFI:
2562 Define if the flash driver uses extra elements in the
2563 common flash structure for storing flash geometry.
2565 - CONFIG_FLASH_CFI_DRIVER
2566 This option also enables the building of the cfi_flash driver
2567 in the drivers directory
2569 - CONFIG_FLASH_CFI_MTD
2570 This option enables the building of the cfi_mtd driver
2571 in the drivers directory. The driver exports CFI flash
2574 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2575 Use buffered writes to flash.
2577 - CONFIG_FLASH_SPANSION_S29WS_N
2578 s29ws-n MirrorBit flash has non-standard addresses for buffered
2581 - CONFIG_SYS_FLASH_QUIET_TEST
2582 If this option is defined, the common CFI flash doesn't
2583 print it's warning upon not recognized FLASH banks. This
2584 is useful, if some of the configured banks are only
2585 optionally available.
2587 - CONFIG_FLASH_SHOW_PROGRESS
2588 If defined (must be an integer), print out countdown
2589 digits and dots. Recommended value: 45 (9..1) for 80
2590 column displays, 15 (3..1) for 40 column displays.
2592 - CONFIG_SYS_RX_ETH_BUFFER:
2593 Defines the number of Ethernet receive buffers. On some
2594 Ethernet controllers it is recommended to set this value
2595 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2596 buffers can be full shortly after enabling the interface
2597 on high Ethernet traffic.
2598 Defaults to 4 if not defined.
2600 - CONFIG_ENV_MAX_ENTRIES
2602 Maximum number of entries in the hash table that is used
2603 internally to store the environment settings. The default
2604 setting is supposed to be generous and should work in most
2605 cases. This setting can be used to tune behaviour; see
2606 lib/hashtable.c for details.
2608 The following definitions that deal with the placement and management
2609 of environment data (variable area); in general, we support the
2610 following configurations:
2612 - CONFIG_BUILD_ENVCRC:
2614 Builds up envcrc with the target environment so that external utils
2615 may easily extract it and embed it in final U-Boot images.
2617 - CONFIG_ENV_IS_IN_FLASH:
2619 Define this if the environment is in flash memory.
2621 a) The environment occupies one whole flash sector, which is
2622 "embedded" in the text segment with the U-Boot code. This
2623 happens usually with "bottom boot sector" or "top boot
2624 sector" type flash chips, which have several smaller
2625 sectors at the start or the end. For instance, such a
2626 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2627 such a case you would place the environment in one of the
2628 4 kB sectors - with U-Boot code before and after it. With
2629 "top boot sector" type flash chips, you would put the
2630 environment in one of the last sectors, leaving a gap
2631 between U-Boot and the environment.
2633 - CONFIG_ENV_OFFSET:
2635 Offset of environment data (variable area) to the
2636 beginning of flash memory; for instance, with bottom boot
2637 type flash chips the second sector can be used: the offset
2638 for this sector is given here.
2640 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2644 This is just another way to specify the start address of
2645 the flash sector containing the environment (instead of
2648 - CONFIG_ENV_SECT_SIZE:
2650 Size of the sector containing the environment.
2653 b) Sometimes flash chips have few, equal sized, BIG sectors.
2654 In such a case you don't want to spend a whole sector for
2659 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2660 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2661 of this flash sector for the environment. This saves
2662 memory for the RAM copy of the environment.
2664 It may also save flash memory if you decide to use this
2665 when your environment is "embedded" within U-Boot code,
2666 since then the remainder of the flash sector could be used
2667 for U-Boot code. It should be pointed out that this is
2668 STRONGLY DISCOURAGED from a robustness point of view:
2669 updating the environment in flash makes it always
2670 necessary to erase the WHOLE sector. If something goes
2671 wrong before the contents has been restored from a copy in
2672 RAM, your target system will be dead.
2674 - CONFIG_ENV_ADDR_REDUND
2675 CONFIG_ENV_SIZE_REDUND
2677 These settings describe a second storage area used to hold
2678 a redundant copy of the environment data, so that there is
2679 a valid backup copy in case there is a power failure during
2680 a "saveenv" operation.
2682 BE CAREFUL! Any changes to the flash layout, and some changes to the
2683 source code will make it necessary to adapt <board>/u-boot.lds*
2687 - CONFIG_ENV_IS_IN_NVRAM:
2689 Define this if you have some non-volatile memory device
2690 (NVRAM, battery buffered SRAM) which you want to use for the
2696 These two #defines are used to determine the memory area you
2697 want to use for environment. It is assumed that this memory
2698 can just be read and written to, without any special
2701 BE CAREFUL! The first access to the environment happens quite early
2702 in U-Boot initalization (when we try to get the setting of for the
2703 console baudrate). You *MUST* have mapped your NVRAM area then, or
2706 Please note that even with NVRAM we still use a copy of the
2707 environment in RAM: we could work on NVRAM directly, but we want to
2708 keep settings there always unmodified except somebody uses "saveenv"
2709 to save the current settings.
2712 - CONFIG_ENV_IS_IN_EEPROM:
2714 Use this if you have an EEPROM or similar serial access
2715 device and a driver for it.
2717 - CONFIG_ENV_OFFSET:
2720 These two #defines specify the offset and size of the
2721 environment area within the total memory of your EEPROM.
2723 - CONFIG_SYS_I2C_EEPROM_ADDR:
2724 If defined, specified the chip address of the EEPROM device.
2725 The default address is zero.
2727 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2728 If defined, the number of bits used to address bytes in a
2729 single page in the EEPROM device. A 64 byte page, for example
2730 would require six bits.
2732 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2733 If defined, the number of milliseconds to delay between
2734 page writes. The default is zero milliseconds.
2736 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2737 The length in bytes of the EEPROM memory array address. Note
2738 that this is NOT the chip address length!
2740 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2741 EEPROM chips that implement "address overflow" are ones
2742 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2743 address and the extra bits end up in the "chip address" bit
2744 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2747 Note that we consider the length of the address field to
2748 still be one byte because the extra address bits are hidden
2749 in the chip address.
2751 - CONFIG_SYS_EEPROM_SIZE:
2752 The size in bytes of the EEPROM device.
2754 - CONFIG_ENV_EEPROM_IS_ON_I2C
2755 define this, if you have I2C and SPI activated, and your
2756 EEPROM, which holds the environment, is on the I2C bus.
2758 - CONFIG_I2C_ENV_EEPROM_BUS
2759 if you have an Environment on an EEPROM reached over
2760 I2C muxes, you can define here, how to reach this
2761 EEPROM. For example:
2763 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2765 EEPROM which holds the environment, is reached over
2766 a pca9547 i2c mux with address 0x70, channel 3.
2768 - CONFIG_ENV_IS_IN_DATAFLASH:
2770 Define this if you have a DataFlash memory device which you
2771 want to use for the environment.
2773 - CONFIG_ENV_OFFSET:
2777 These three #defines specify the offset and size of the
2778 environment area within the total memory of your DataFlash placed
2779 at the specified address.
2781 - CONFIG_ENV_IS_IN_NAND:
2783 Define this if you have a NAND device which you want to use
2784 for the environment.
2786 - CONFIG_ENV_OFFSET:
2789 These two #defines specify the offset and size of the environment
2790 area within the first NAND device. CONFIG_ENV_OFFSET must be
2791 aligned to an erase block boundary.
2793 - CONFIG_ENV_OFFSET_REDUND (optional):
2795 This setting describes a second storage area of CONFIG_ENV_SIZE
2796 size used to hold a redundant copy of the environment data, so
2797 that there is a valid backup copy in case there is a power failure
2798 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2799 aligned to an erase block boundary.
2801 - CONFIG_ENV_RANGE (optional):
2803 Specifies the length of the region in which the environment
2804 can be written. This should be a multiple of the NAND device's
2805 block size. Specifying a range with more erase blocks than
2806 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2807 the range to be avoided.
2809 - CONFIG_ENV_OFFSET_OOB (optional):
2811 Enables support for dynamically retrieving the offset of the
2812 environment from block zero's out-of-band data. The
2813 "nand env.oob" command can be used to record this offset.
2814 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2815 using CONFIG_ENV_OFFSET_OOB.
2817 - CONFIG_NAND_ENV_DST
2819 Defines address in RAM to which the nand_spl code should copy the
2820 environment. If redundant environment is used, it will be copied to
2821 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2823 - CONFIG_SYS_SPI_INIT_OFFSET
2825 Defines offset to the initial SPI buffer area in DPRAM. The
2826 area is used at an early stage (ROM part) if the environment
2827 is configured to reside in the SPI EEPROM: We need a 520 byte
2828 scratch DPRAM area. It is used between the two initialization
2829 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2830 to be a good choice since it makes it far enough from the
2831 start of the data area as well as from the stack pointer.
2833 Please note that the environment is read-only until the monitor
2834 has been relocated to RAM and a RAM copy of the environment has been
2835 created; also, when using EEPROM you will have to use getenv_f()
2836 until then to read environment variables.
2838 The environment is protected by a CRC32 checksum. Before the monitor
2839 is relocated into RAM, as a result of a bad CRC you will be working
2840 with the compiled-in default environment - *silently*!!! [This is
2841 necessary, because the first environment variable we need is the
2842 "baudrate" setting for the console - if we have a bad CRC, we don't
2843 have any device yet where we could complain.]
2845 Note: once the monitor has been relocated, then it will complain if
2846 the default environment is used; a new CRC is computed as soon as you
2847 use the "saveenv" command to store a valid environment.
2849 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2850 Echo the inverted Ethernet link state to the fault LED.
2852 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2853 also needs to be defined.
2855 - CONFIG_SYS_FAULT_MII_ADDR:
2856 MII address of the PHY to check for the Ethernet link state.
2858 - CONFIG_NS16550_MIN_FUNCTIONS:
2859 Define this if you desire to only have use of the NS16550_init
2860 and NS16550_putc functions for the serial driver located at
2861 drivers/serial/ns16550.c. This option is useful for saving
2862 space for already greatly restricted images, including but not
2863 limited to NAND_SPL configurations.
2865 Low Level (hardware related) configuration options:
2866 ---------------------------------------------------
2868 - CONFIG_SYS_CACHELINE_SIZE:
2869 Cache Line Size of the CPU.
2871 - CONFIG_SYS_DEFAULT_IMMR:
2872 Default address of the IMMR after system reset.
2874 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2875 and RPXsuper) to be able to adjust the position of
2876 the IMMR register after a reset.
2878 - CONFIG_SYS_CCSRBAR_DEFAULT:
2879 Default (power-on reset) physical address of CCSR on Freescale
2882 - CONFIG_SYS_CCSRBAR:
2883 Virtual address of CCSR. On a 32-bit build, this is typically
2884 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
2886 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
2887 for cross-platform code that uses that macro instead.
2889 - CONFIG_SYS_CCSRBAR_PHYS:
2890 Physical address of CCSR. CCSR can be relocated to a new
2891 physical address, if desired. In this case, this macro should
2892 be set to that address. Otherwise, it should be set to the
2893 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
2894 is typically relocated on 36-bit builds. It is recommended
2895 that this macro be defined via the _HIGH and _LOW macros:
2897 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
2898 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
2900 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
2901 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
2902 either 0 (32-bit build) or 0xF (36-bit build). This macro is
2903 used in assembly code, so it must not contain typecasts or
2904 integer size suffixes (e.g. "ULL").
2906 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
2907 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
2908 used in assembly code, so it must not contain typecasts or
2909 integer size suffixes (e.g. "ULL").
2911 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
2912 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
2913 forced to a value that ensures that CCSR is not relocated.
2915 - Floppy Disk Support:
2916 CONFIG_SYS_FDC_DRIVE_NUMBER
2918 the default drive number (default value 0)
2920 CONFIG_SYS_ISA_IO_STRIDE
2922 defines the spacing between FDC chipset registers
2925 CONFIG_SYS_ISA_IO_OFFSET
2927 defines the offset of register from address. It
2928 depends on which part of the data bus is connected to
2929 the FDC chipset. (default value 0)
2931 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2932 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2935 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2936 fdc_hw_init() is called at the beginning of the FDC
2937 setup. fdc_hw_init() must be provided by the board
2938 source code. It is used to make hardware dependant
2942 Most IDE controllers were designed to be connected with PCI
2943 interface. Only few of them were designed for AHB interface.
2944 When software is doing ATA command and data transfer to
2945 IDE devices through IDE-AHB controller, some additional
2946 registers accessing to these kind of IDE-AHB controller
2949 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2950 DO NOT CHANGE unless you know exactly what you're
2951 doing! (11-4) [MPC8xx/82xx systems only]
2953 - CONFIG_SYS_INIT_RAM_ADDR:
2955 Start address of memory area that can be used for
2956 initial data and stack; please note that this must be
2957 writable memory that is working WITHOUT special
2958 initialization, i. e. you CANNOT use normal RAM which
2959 will become available only after programming the
2960 memory controller and running certain initialization
2963 U-Boot uses the following memory types:
2964 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2965 - MPC824X: data cache
2966 - PPC4xx: data cache
2968 - CONFIG_SYS_GBL_DATA_OFFSET:
2970 Offset of the initial data structure in the memory
2971 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2972 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2973 data is located at the end of the available space
2974 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2975 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2976 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2977 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2980 On the MPC824X (or other systems that use the data
2981 cache for initial memory) the address chosen for
2982 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2983 point to an otherwise UNUSED address space between
2984 the top of RAM and the start of the PCI space.
2986 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2988 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2990 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2992 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2994 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2996 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2998 - CONFIG_SYS_OR_TIMING_SDRAM:
3001 - CONFIG_SYS_MAMR_PTA:
3002 periodic timer for refresh
3004 - CONFIG_SYS_DER: Debug Event Register (37-47)
3006 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3007 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3008 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3009 CONFIG_SYS_BR1_PRELIM:
3010 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3012 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3013 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3014 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3015 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3017 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3018 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3019 Machine Mode Register and Memory Periodic Timer
3020 Prescaler definitions (SDRAM timing)
3022 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3023 enable I2C microcode relocation patch (MPC8xx);
3024 define relocation offset in DPRAM [DSP2]
3026 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3027 enable SMC microcode relocation patch (MPC8xx);
3028 define relocation offset in DPRAM [SMC1]
3030 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3031 enable SPI microcode relocation patch (MPC8xx);
3032 define relocation offset in DPRAM [SCC4]
3034 - CONFIG_SYS_USE_OSCCLK:
3035 Use OSCM clock mode on MBX8xx board. Be careful,
3036 wrong setting might damage your board. Read
3037 doc/README.MBX before setting this variable!
3039 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3040 Offset of the bootmode word in DPRAM used by post
3041 (Power On Self Tests). This definition overrides
3042 #define'd default value in commproc.h resp.
3045 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3046 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3047 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3048 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3049 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3050 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3051 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3052 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3053 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3055 - CONFIG_PCI_DISABLE_PCIE:
3056 Disable PCI-Express on systems where it is supported but not
3060 Chip has SRIO or not
3063 Board has SRIO 1 port available
3066 Board has SRIO 2 port available
3068 - CONFIG_SYS_SRIOn_MEM_VIRT:
3069 Virtual Address of SRIO port 'n' memory region
3071 - CONFIG_SYS_SRIOn_MEM_PHYS:
3072 Physical Address of SRIO port 'n' memory region
3074 - CONFIG_SYS_SRIOn_MEM_SIZE:
3075 Size of SRIO port 'n' memory region
3077 - CONFIG_SYS_NDFC_16
3078 Defined to tell the NDFC that the NAND chip is using a
3081 - CONFIG_SYS_NDFC_EBC0_CFG
3082 Sets the EBC0_CFG register for the NDFC. If not defined
3083 a default value will be used.
3086 Get DDR timing information from an I2C EEPROM. Common
3087 with pluggable memory modules such as SODIMMs
3090 I2C address of the SPD EEPROM
3092 - CONFIG_SYS_SPD_BUS_NUM
3093 If SPD EEPROM is on an I2C bus other than the first
3094 one, specify here. Note that the value must resolve
3095 to something your driver can deal with.
3097 - CONFIG_SYS_DDR_RAW_TIMING
3098 Get DDR timing information from other than SPD. Common with
3099 soldered DDR chips onboard without SPD. DDR raw timing
3100 parameters are extracted from datasheet and hard-coded into
3101 header files or board specific files.
3103 - CONFIG_FSL_DDR_INTERACTIVE
3104 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3106 - CONFIG_SYS_83XX_DDR_USES_CS0
3107 Only for 83xx systems. If specified, then DDR should
3108 be configured using CS0 and CS1 instead of CS2 and CS3.
3110 - CONFIG_ETHER_ON_FEC[12]
3111 Define to enable FEC[12] on a 8xx series processor.
3113 - CONFIG_FEC[12]_PHY
3114 Define to the hardcoded PHY address which corresponds
3115 to the given FEC; i. e.
3116 #define CONFIG_FEC1_PHY 4
3117 means that the PHY with address 4 is connected to FEC1
3119 When set to -1, means to probe for first available.
3121 - CONFIG_FEC[12]_PHY_NORXERR
3122 The PHY does not have a RXERR line (RMII only).
3123 (so program the FEC to ignore it).
3126 Enable RMII mode for all FECs.
3127 Note that this is a global option, we can't
3128 have one FEC in standard MII mode and another in RMII mode.
3130 - CONFIG_CRC32_VERIFY
3131 Add a verify option to the crc32 command.
3134 => crc32 -v <address> <count> <crc32>
3136 Where address/count indicate a memory area
3137 and crc32 is the correct crc32 which the
3141 Add the "loopw" memory command. This only takes effect if
3142 the memory commands are activated globally (CONFIG_CMD_MEM).
3145 Add the "mdc" and "mwc" memory commands. These are cyclic
3150 This command will print 4 bytes (10,11,12,13) each 500 ms.
3152 => mwc.l 100 12345678 10
3153 This command will write 12345678 to address 100 all 10 ms.
3155 This only takes effect if the memory commands are activated
3156 globally (CONFIG_CMD_MEM).
3158 - CONFIG_SKIP_LOWLEVEL_INIT
3159 [ARM, MIPS only] If this variable is defined, then certain
3160 low level initializations (like setting up the memory
3161 controller) are omitted and/or U-Boot does not
3162 relocate itself into RAM.
3164 Normally this variable MUST NOT be defined. The only
3165 exception is when U-Boot is loaded (to RAM) by some
3166 other boot loader or by a debugger which performs
3167 these initializations itself.
3170 Modifies the behaviour of start.S when compiling a loader
3171 that is executed before the actual U-Boot. E.g. when
3172 compiling a NAND SPL.
3174 - CONFIG_USE_ARCH_MEMCPY
3175 CONFIG_USE_ARCH_MEMSET
3176 If these options are used a optimized version of memcpy/memset will
3177 be used if available. These functions may be faster under some
3178 conditions but may increase the binary size.
3180 Building the Software:
3181 ======================
3183 Building U-Boot has been tested in several native build environments
3184 and in many different cross environments. Of course we cannot support
3185 all possibly existing versions of cross development tools in all
3186 (potentially obsolete) versions. In case of tool chain problems we
3187 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3188 which is extensively used to build and test U-Boot.
3190 If you are not using a native environment, it is assumed that you
3191 have GNU cross compiling tools available in your path. In this case,
3192 you must set the environment variable CROSS_COMPILE in your shell.
3193 Note that no changes to the Makefile or any other source files are
3194 necessary. For example using the ELDK on a 4xx CPU, please enter:
3196 $ CROSS_COMPILE=ppc_4xx-
3197 $ export CROSS_COMPILE
3199 Note: If you wish to generate Windows versions of the utilities in
3200 the tools directory you can use the MinGW toolchain
3201 (http://www.mingw.org). Set your HOST tools to the MinGW
3202 toolchain and execute 'make tools'. For example:
3204 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3206 Binaries such as tools/mkimage.exe will be created which can
3207 be executed on computers running Windows.
3209 U-Boot is intended to be simple to build. After installing the
3210 sources you must configure U-Boot for one specific board type. This
3215 where "NAME_config" is the name of one of the existing configu-
3216 rations; see the main Makefile for supported names.
3218 Note: for some board special configuration names may exist; check if
3219 additional information is available from the board vendor; for
3220 instance, the TQM823L systems are available without (standard)
3221 or with LCD support. You can select such additional "features"
3222 when choosing the configuration, i. e.
3225 - will configure for a plain TQM823L, i. e. no LCD support
3227 make TQM823L_LCD_config
3228 - will configure for a TQM823L with U-Boot console on LCD
3233 Finally, type "make all", and you should get some working U-Boot
3234 images ready for download to / installation on your system:
3236 - "u-boot.bin" is a raw binary image
3237 - "u-boot" is an image in ELF binary format
3238 - "u-boot.srec" is in Motorola S-Record format
3240 By default the build is performed locally and the objects are saved
3241 in the source directory. One of the two methods can be used to change
3242 this behavior and build U-Boot to some external directory:
3244 1. Add O= to the make command line invocations:
3246 make O=/tmp/build distclean
3247 make O=/tmp/build NAME_config
3248 make O=/tmp/build all
3250 2. Set environment variable BUILD_DIR to point to the desired location:
3252 export BUILD_DIR=/tmp/build
3257 Note that the command line "O=" setting overrides the BUILD_DIR environment
3261 Please be aware that the Makefiles assume you are using GNU make, so
3262 for instance on NetBSD you might need to use "gmake" instead of
3266 If the system board that you have is not listed, then you will need
3267 to port U-Boot to your hardware platform. To do this, follow these
3270 1. Add a new configuration option for your board to the toplevel
3271 "Makefile" and to the "MAKEALL" script, using the existing
3272 entries as examples. Note that here and at many other places
3273 boards and other names are listed in alphabetical sort order. Please
3275 2. Create a new directory to hold your board specific code. Add any
3276 files you need. In your board directory, you will need at least
3277 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3278 3. Create a new configuration file "include/configs/<board>.h" for
3280 3. If you're porting U-Boot to a new CPU, then also create a new
3281 directory to hold your CPU specific code. Add any files you need.
3282 4. Run "make <board>_config" with your new name.
3283 5. Type "make", and you should get a working "u-boot.srec" file
3284 to be installed on your target system.
3285 6. Debug and solve any problems that might arise.
3286 [Of course, this last step is much harder than it sounds.]
3289 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3290 ==============================================================
3292 If you have modified U-Boot sources (for instance added a new board
3293 or support for new devices, a new CPU, etc.) you are expected to
3294 provide feedback to the other developers. The feedback normally takes
3295 the form of a "patch", i. e. a context diff against a certain (latest
3296 official or latest in the git repository) version of U-Boot sources.
3298 But before you submit such a patch, please verify that your modifi-
3299 cation did not break existing code. At least make sure that *ALL* of
3300 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3301 just run the "MAKEALL" script, which will configure and build U-Boot
3302 for ALL supported system. Be warned, this will take a while. You can
3303 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3304 environment variable to the script, i. e. to use the ELDK cross tools
3307 CROSS_COMPILE=ppc_8xx- MAKEALL
3309 or to build on a native PowerPC system you can type
3311 CROSS_COMPILE=' ' MAKEALL
3313 When using the MAKEALL script, the default behaviour is to build
3314 U-Boot in the source directory. This location can be changed by
3315 setting the BUILD_DIR environment variable. Also, for each target
3316 built, the MAKEALL script saves two log files (<target>.ERR and
3317 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3318 location can be changed by setting the MAKEALL_LOGDIR environment
3319 variable. For example:
3321 export BUILD_DIR=/tmp/build
3322 export MAKEALL_LOGDIR=/tmp/log
3323 CROSS_COMPILE=ppc_8xx- MAKEALL
3325 With the above settings build objects are saved in the /tmp/build,
3326 log files are saved in the /tmp/log and the source tree remains clean
3327 during the whole build process.
3330 See also "U-Boot Porting Guide" below.
3333 Monitor Commands - Overview:
3334 ============================
3336 go - start application at address 'addr'
3337 run - run commands in an environment variable
3338 bootm - boot application image from memory
3339 bootp - boot image via network using BootP/TFTP protocol
3340 tftpboot- boot image via network using TFTP protocol
3341 and env variables "ipaddr" and "serverip"
3342 (and eventually "gatewayip")
3343 rarpboot- boot image via network using RARP/TFTP protocol
3344 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3345 loads - load S-Record file over serial line
3346 loadb - load binary file over serial line (kermit mode)
3348 mm - memory modify (auto-incrementing)
3349 nm - memory modify (constant address)
3350 mw - memory write (fill)
3352 cmp - memory compare
3353 crc32 - checksum calculation
3354 i2c - I2C sub-system
3355 sspi - SPI utility commands
3356 base - print or set address offset
3357 printenv- print environment variables
3358 setenv - set environment variables
3359 saveenv - save environment variables to persistent storage
3360 protect - enable or disable FLASH write protection
3361 erase - erase FLASH memory
3362 flinfo - print FLASH memory information
3363 bdinfo - print Board Info structure
3364 iminfo - print header information for application image
3365 coninfo - print console devices and informations
3366 ide - IDE sub-system
3367 loop - infinite loop on address range
3368 loopw - infinite write loop on address range
3369 mtest - simple RAM test
3370 icache - enable or disable instruction cache
3371 dcache - enable or disable data cache
3372 reset - Perform RESET of the CPU
3373 echo - echo args to console
3374 version - print monitor version
3375 help - print online help
3376 ? - alias for 'help'
3379 Monitor Commands - Detailed Description:
3380 ========================================
3384 For now: just type "help <command>".
3387 Environment Variables:
3388 ======================
3390 U-Boot supports user configuration using Environment Variables which
3391 can be made persistent by saving to Flash memory.
3393 Environment Variables are set using "setenv", printed using
3394 "printenv", and saved to Flash using "saveenv". Using "setenv"
3395 without a value can be used to delete a variable from the
3396 environment. As long as you don't save the environment you are
3397 working with an in-memory copy. In case the Flash area containing the
3398 environment is erased by accident, a default environment is provided.
3400 Some configuration options can be set using Environment Variables.
3402 List of environment variables (most likely not complete):
3404 baudrate - see CONFIG_BAUDRATE
3406 bootdelay - see CONFIG_BOOTDELAY
3408 bootcmd - see CONFIG_BOOTCOMMAND
3410 bootargs - Boot arguments when booting an RTOS image
3412 bootfile - Name of the image to load with TFTP
3414 bootm_low - Memory range available for image processing in the bootm
3415 command can be restricted. This variable is given as
3416 a hexadecimal number and defines lowest address allowed
3417 for use by the bootm command. See also "bootm_size"
3418 environment variable. Address defined by "bootm_low" is
3419 also the base of the initial memory mapping for the Linux
3420 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3423 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3424 This variable is given as a hexadecimal number and it
3425 defines the size of the memory region starting at base
3426 address bootm_low that is accessible by the Linux kernel
3427 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3428 as the default value if it is defined, and bootm_size is
3431 bootm_size - Memory range available for image processing in the bootm
3432 command can be restricted. This variable is given as
3433 a hexadecimal number and defines the size of the region
3434 allowed for use by the bootm command. See also "bootm_low"
3435 environment variable.
3437 updatefile - Location of the software update file on a TFTP server, used
3438 by the automatic software update feature. Please refer to
3439 documentation in doc/README.update for more details.
3441 autoload - if set to "no" (any string beginning with 'n'),
3442 "bootp" will just load perform a lookup of the
3443 configuration from the BOOTP server, but not try to
3444 load any image using TFTP
3446 autostart - if set to "yes", an image loaded using the "bootp",
3447 "rarpboot", "tftpboot" or "diskboot" commands will
3448 be automatically started (by internally calling
3451 If set to "no", a standalone image passed to the
3452 "bootm" command will be copied to the load address
3453 (and eventually uncompressed), but NOT be started.
3454 This can be used to load and uncompress arbitrary
3457 fdt_high - if set this restricts the maximum address that the
3458 flattened device tree will be copied into upon boot.
3459 If this is set to the special value 0xFFFFFFFF then
3460 the fdt will not be copied at all on boot. For this
3461 to work it must reside in writable memory, have
3462 sufficient padding on the end of it for u-boot to
3463 add the information it needs into it, and the memory
3464 must be accessible by the kernel.
3466 i2cfast - (PPC405GP|PPC405EP only)
3467 if set to 'y' configures Linux I2C driver for fast
3468 mode (400kHZ). This environment variable is used in
3469 initialization code. So, for changes to be effective
3470 it must be saved and board must be reset.
3472 initrd_high - restrict positioning of initrd images:
3473 If this variable is not set, initrd images will be
3474 copied to the highest possible address in RAM; this
3475 is usually what you want since it allows for
3476 maximum initrd size. If for some reason you want to
3477 make sure that the initrd image is loaded below the
3478 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3479 variable to a value of "no" or "off" or "0".
3480 Alternatively, you can set it to a maximum upper
3481 address to use (U-Boot will still check that it
3482 does not overwrite the U-Boot stack and data).
3484 For instance, when you have a system with 16 MB
3485 RAM, and want to reserve 4 MB from use by Linux,
3486 you can do this by adding "mem=12M" to the value of
3487 the "bootargs" variable. However, now you must make
3488 sure that the initrd image is placed in the first
3489 12 MB as well - this can be done with
3491 setenv initrd_high 00c00000
3493 If you set initrd_high to 0xFFFFFFFF, this is an
3494 indication to U-Boot that all addresses are legal
3495 for the Linux kernel, including addresses in flash
3496 memory. In this case U-Boot will NOT COPY the
3497 ramdisk at all. This may be useful to reduce the
3498 boot time on your system, but requires that this
3499 feature is supported by your Linux kernel.
3501 ipaddr - IP address; needed for tftpboot command
3503 loadaddr - Default load address for commands like "bootp",
3504 "rarpboot", "tftpboot", "loadb" or "diskboot"
3506 loads_echo - see CONFIG_LOADS_ECHO
3508 serverip - TFTP server IP address; needed for tftpboot command
3510 bootretry - see CONFIG_BOOT_RETRY_TIME
3512 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3514 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3516 ethprime - controls which interface is used first.
3518 ethact - controls which interface is currently active.
3519 For example you can do the following
3521 => setenv ethact FEC
3522 => ping 192.168.0.1 # traffic sent on FEC
3523 => setenv ethact SCC
3524 => ping 10.0.0.1 # traffic sent on SCC
3526 ethrotate - When set to "no" U-Boot does not go through all
3527 available network interfaces.
3528 It just stays at the currently selected interface.
3530 netretry - When set to "no" each network operation will
3531 either succeed or fail without retrying.
3532 When set to "once" the network operation will
3533 fail when all the available network interfaces
3534 are tried once without success.
3535 Useful on scripts which control the retry operation
3538 npe_ucode - set load address for the NPE microcode
3540 tftpsrcport - If this is set, the value is used for TFTP's
3543 tftpdstport - If this is set, the value is used for TFTP's UDP
3544 destination port instead of the Well Know Port 69.
3546 tftpblocksize - Block size to use for TFTP transfers; if not set,
3547 we use the TFTP server's default block size
3549 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3550 seconds, minimum value is 1000 = 1 second). Defines
3551 when a packet is considered to be lost so it has to
3552 be retransmitted. The default is 5000 = 5 seconds.
3553 Lowering this value may make downloads succeed
3554 faster in networks with high packet loss rates or
3555 with unreliable TFTP servers.
3557 vlan - When set to a value < 4095 the traffic over
3558 Ethernet is encapsulated/received over 802.1q
3561 The following image location variables contain the location of images
3562 used in booting. The "Image" column gives the role of the image and is
3563 not an environment variable name. The other columns are environment
3564 variable names. "File Name" gives the name of the file on a TFTP
3565 server, "RAM Address" gives the location in RAM the image will be
3566 loaded to, and "Flash Location" gives the image's address in NOR
3567 flash or offset in NAND flash.
3569 *Note* - these variables don't have to be defined for all boards, some
3570 boards currenlty use other variables for these purposes, and some
3571 boards use these variables for other purposes.
3573 Image File Name RAM Address Flash Location
3574 ----- --------- ----------- --------------
3575 u-boot u-boot u-boot_addr_r u-boot_addr
3576 Linux kernel bootfile kernel_addr_r kernel_addr
3577 device tree blob fdtfile fdt_addr_r fdt_addr
3578 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
3580 The following environment variables may be used and automatically
3581 updated by the network boot commands ("bootp" and "rarpboot"),
3582 depending the information provided by your boot server:
3584 bootfile - see above
3585 dnsip - IP address of your Domain Name Server
3586 dnsip2 - IP address of your secondary Domain Name Server
3587 gatewayip - IP address of the Gateway (Router) to use
3588 hostname - Target hostname
3590 netmask - Subnet Mask
3591 rootpath - Pathname of the root filesystem on the NFS server
3592 serverip - see above
3595 There are two special Environment Variables:
3597 serial# - contains hardware identification information such
3598 as type string and/or serial number
3599 ethaddr - Ethernet address
3601 These variables can be set only once (usually during manufacturing of
3602 the board). U-Boot refuses to delete or overwrite these variables
3603 once they have been set once.
3606 Further special Environment Variables:
3608 ver - Contains the U-Boot version string as printed
3609 with the "version" command. This variable is
3610 readonly (see CONFIG_VERSION_VARIABLE).
3613 Please note that changes to some configuration parameters may take
3614 only effect after the next boot (yes, that's just like Windoze :-).
3617 Command Line Parsing:
3618 =====================
3620 There are two different command line parsers available with U-Boot:
3621 the old "simple" one, and the much more powerful "hush" shell:
3623 Old, simple command line parser:
3624 --------------------------------
3626 - supports environment variables (through setenv / saveenv commands)
3627 - several commands on one line, separated by ';'
3628 - variable substitution using "... ${name} ..." syntax
3629 - special characters ('$', ';') can be escaped by prefixing with '\',
3631 setenv bootcmd bootm \${address}
3632 - You can also escape text by enclosing in single apostrophes, for example:
3633 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3638 - similar to Bourne shell, with control structures like
3639 if...then...else...fi, for...do...done; while...do...done,
3640 until...do...done, ...
3641 - supports environment ("global") variables (through setenv / saveenv
3642 commands) and local shell variables (through standard shell syntax
3643 "name=value"); only environment variables can be used with "run"
3649 (1) If a command line (or an environment variable executed by a "run"
3650 command) contains several commands separated by semicolon, and
3651 one of these commands fails, then the remaining commands will be
3654 (2) If you execute several variables with one call to run (i. e.
3655 calling run with a list of variables as arguments), any failing
3656 command will cause "run" to terminate, i. e. the remaining
3657 variables are not executed.
3659 Note for Redundant Ethernet Interfaces:
3660 =======================================
3662 Some boards come with redundant Ethernet interfaces; U-Boot supports
3663 such configurations and is capable of automatic selection of a
3664 "working" interface when needed. MAC assignment works as follows:
3666 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3667 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3668 "eth1addr" (=>eth1), "eth2addr", ...
3670 If the network interface stores some valid MAC address (for instance
3671 in SROM), this is used as default address if there is NO correspon-
3672 ding setting in the environment; if the corresponding environment
3673 variable is set, this overrides the settings in the card; that means:
3675 o If the SROM has a valid MAC address, and there is no address in the
3676 environment, the SROM's address is used.
3678 o If there is no valid address in the SROM, and a definition in the
3679 environment exists, then the value from the environment variable is
3682 o If both the SROM and the environment contain a MAC address, and
3683 both addresses are the same, this MAC address is used.
3685 o If both the SROM and the environment contain a MAC address, and the
3686 addresses differ, the value from the environment is used and a
3689 o If neither SROM nor the environment contain a MAC address, an error
3692 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3693 will be programmed into hardware as part of the initialization process. This
3694 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3695 The naming convention is as follows:
3696 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3701 U-Boot is capable of booting (and performing other auxiliary operations on)
3702 images in two formats:
3704 New uImage format (FIT)
3705 -----------------------
3707 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3708 to Flattened Device Tree). It allows the use of images with multiple
3709 components (several kernels, ramdisks, etc.), with contents protected by
3710 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3716 Old image format is based on binary files which can be basically anything,
3717 preceded by a special header; see the definitions in include/image.h for
3718 details; basically, the header defines the following image properties:
3720 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3721 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3722 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3723 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3725 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3726 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3727 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3728 * Compression Type (uncompressed, gzip, bzip2)
3734 The header is marked by a special Magic Number, and both the header
3735 and the data portions of the image are secured against corruption by
3742 Although U-Boot should support any OS or standalone application
3743 easily, the main focus has always been on Linux during the design of
3746 U-Boot includes many features that so far have been part of some
3747 special "boot loader" code within the Linux kernel. Also, any
3748 "initrd" images to be used are no longer part of one big Linux image;
3749 instead, kernel and "initrd" are separate images. This implementation
3750 serves several purposes:
3752 - the same features can be used for other OS or standalone
3753 applications (for instance: using compressed images to reduce the
3754 Flash memory footprint)
3756 - it becomes much easier to port new Linux kernel versions because
3757 lots of low-level, hardware dependent stuff are done by U-Boot
3759 - the same Linux kernel image can now be used with different "initrd"
3760 images; of course this also means that different kernel images can
3761 be run with the same "initrd". This makes testing easier (you don't
3762 have to build a new "zImage.initrd" Linux image when you just
3763 change a file in your "initrd"). Also, a field-upgrade of the
3764 software is easier now.
3770 Porting Linux to U-Boot based systems:
3771 ---------------------------------------
3773 U-Boot cannot save you from doing all the necessary modifications to
3774 configure the Linux device drivers for use with your target hardware
3775 (no, we don't intend to provide a full virtual machine interface to
3778 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3780 Just make sure your machine specific header file (for instance
3781 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3782 Information structure as we define in include/asm-<arch>/u-boot.h,
3783 and make sure that your definition of IMAP_ADDR uses the same value
3784 as your U-Boot configuration in CONFIG_SYS_IMMR.
3787 Configuring the Linux kernel:
3788 -----------------------------
3790 No specific requirements for U-Boot. Make sure you have some root
3791 device (initial ramdisk, NFS) for your target system.
3794 Building a Linux Image:
3795 -----------------------
3797 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3798 not used. If you use recent kernel source, a new build target
3799 "uImage" will exist which automatically builds an image usable by
3800 U-Boot. Most older kernels also have support for a "pImage" target,
3801 which was introduced for our predecessor project PPCBoot and uses a
3802 100% compatible format.
3811 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3812 encapsulate a compressed Linux kernel image with header information,
3813 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3815 * build a standard "vmlinux" kernel image (in ELF binary format):
3817 * convert the kernel into a raw binary image:
3819 ${CROSS_COMPILE}-objcopy -O binary \
3820 -R .note -R .comment \
3821 -S vmlinux linux.bin
3823 * compress the binary image:
3827 * package compressed binary image for U-Boot:
3829 mkimage -A ppc -O linux -T kernel -C gzip \
3830 -a 0 -e 0 -n "Linux Kernel Image" \
3831 -d linux.bin.gz uImage
3834 The "mkimage" tool can also be used to create ramdisk images for use
3835 with U-Boot, either separated from the Linux kernel image, or
3836 combined into one file. "mkimage" encapsulates the images with a 64
3837 byte header containing information about target architecture,
3838 operating system, image type, compression method, entry points, time
3839 stamp, CRC32 checksums, etc.
3841 "mkimage" can be called in two ways: to verify existing images and
3842 print the header information, or to build new images.
3844 In the first form (with "-l" option) mkimage lists the information
3845 contained in the header of an existing U-Boot image; this includes
3846 checksum verification:
3848 tools/mkimage -l image
3849 -l ==> list image header information
3851 The second form (with "-d" option) is used to build a U-Boot image
3852 from a "data file" which is used as image payload:
3854 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3855 -n name -d data_file image
3856 -A ==> set architecture to 'arch'
3857 -O ==> set operating system to 'os'
3858 -T ==> set image type to 'type'
3859 -C ==> set compression type 'comp'
3860 -a ==> set load address to 'addr' (hex)
3861 -e ==> set entry point to 'ep' (hex)
3862 -n ==> set image name to 'name'
3863 -d ==> use image data from 'datafile'
3865 Right now, all Linux kernels for PowerPC systems use the same load
3866 address (0x00000000), but the entry point address depends on the
3869 - 2.2.x kernels have the entry point at 0x0000000C,
3870 - 2.3.x and later kernels have the entry point at 0x00000000.
3872 So a typical call to build a U-Boot image would read:
3874 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3875 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3876 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3877 > examples/uImage.TQM850L
3878 Image Name: 2.4.4 kernel for TQM850L
3879 Created: Wed Jul 19 02:34:59 2000
3880 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3881 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3882 Load Address: 0x00000000
3883 Entry Point: 0x00000000
3885 To verify the contents of the image (or check for corruption):
3887 -> tools/mkimage -l examples/uImage.TQM850L
3888 Image Name: 2.4.4 kernel for TQM850L
3889 Created: Wed Jul 19 02:34:59 2000
3890 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3891 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3892 Load Address: 0x00000000
3893 Entry Point: 0x00000000
3895 NOTE: for embedded systems where boot time is critical you can trade
3896 speed for memory and install an UNCOMPRESSED image instead: this
3897 needs more space in Flash, but boots much faster since it does not
3898 need to be uncompressed:
3900 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3901 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3902 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3903 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3904 > examples/uImage.TQM850L-uncompressed
3905 Image Name: 2.4.4 kernel for TQM850L
3906 Created: Wed Jul 19 02:34:59 2000
3907 Image Type: PowerPC Linux Kernel Image (uncompressed)
3908 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3909 Load Address: 0x00000000
3910 Entry Point: 0x00000000
3913 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3914 when your kernel is intended to use an initial ramdisk:
3916 -> tools/mkimage -n 'Simple Ramdisk Image' \
3917 > -A ppc -O linux -T ramdisk -C gzip \
3918 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3919 Image Name: Simple Ramdisk Image
3920 Created: Wed Jan 12 14:01:50 2000
3921 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3922 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3923 Load Address: 0x00000000
3924 Entry Point: 0x00000000
3927 Installing a Linux Image:
3928 -------------------------
3930 To downloading a U-Boot image over the serial (console) interface,
3931 you must convert the image to S-Record format:
3933 objcopy -I binary -O srec examples/image examples/image.srec
3935 The 'objcopy' does not understand the information in the U-Boot
3936 image header, so the resulting S-Record file will be relative to
3937 address 0x00000000. To load it to a given address, you need to
3938 specify the target address as 'offset' parameter with the 'loads'
3941 Example: install the image to address 0x40100000 (which on the
3942 TQM8xxL is in the first Flash bank):
3944 => erase 40100000 401FFFFF
3950 ## Ready for S-Record download ...
3951 ~>examples/image.srec
3952 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3954 15989 15990 15991 15992
3955 [file transfer complete]
3957 ## Start Addr = 0x00000000
3960 You can check the success of the download using the 'iminfo' command;
3961 this includes a checksum verification so you can be sure no data
3962 corruption happened:
3966 ## Checking Image at 40100000 ...
3967 Image Name: 2.2.13 for initrd on TQM850L
3968 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3969 Data Size: 335725 Bytes = 327 kB = 0 MB
3970 Load Address: 00000000
3971 Entry Point: 0000000c
3972 Verifying Checksum ... OK
3978 The "bootm" command is used to boot an application that is stored in
3979 memory (RAM or Flash). In case of a Linux kernel image, the contents
3980 of the "bootargs" environment variable is passed to the kernel as
3981 parameters. You can check and modify this variable using the
3982 "printenv" and "setenv" commands:
3985 => printenv bootargs
3986 bootargs=root=/dev/ram
3988 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3990 => printenv bootargs
3991 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3994 ## Booting Linux kernel at 40020000 ...
3995 Image Name: 2.2.13 for NFS on TQM850L
3996 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3997 Data Size: 381681 Bytes = 372 kB = 0 MB
3998 Load Address: 00000000
3999 Entry Point: 0000000c
4000 Verifying Checksum ... OK
4001 Uncompressing Kernel Image ... OK
4002 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
4003 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4004 time_init: decrementer frequency = 187500000/60
4005 Calibrating delay loop... 49.77 BogoMIPS
4006 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4009 If you want to boot a Linux kernel with initial RAM disk, you pass
4010 the memory addresses of both the kernel and the initrd image (PPBCOOT
4011 format!) to the "bootm" command:
4013 => imi 40100000 40200000
4015 ## Checking Image at 40100000 ...
4016 Image Name: 2.2.13 for initrd on TQM850L
4017 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4018 Data Size: 335725 Bytes = 327 kB = 0 MB
4019 Load Address: 00000000
4020 Entry Point: 0000000c
4021 Verifying Checksum ... OK
4023 ## Checking Image at 40200000 ...
4024 Image Name: Simple Ramdisk Image
4025 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4026 Data Size: 566530 Bytes = 553 kB = 0 MB
4027 Load Address: 00000000
4028 Entry Point: 00000000
4029 Verifying Checksum ... OK
4031 => bootm 40100000 40200000
4032 ## Booting Linux kernel at 40100000 ...
4033 Image Name: 2.2.13 for initrd on TQM850L
4034 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4035 Data Size: 335725 Bytes = 327 kB = 0 MB
4036 Load Address: 00000000
4037 Entry Point: 0000000c
4038 Verifying Checksum ... OK
4039 Uncompressing Kernel Image ... OK
4040 ## Loading RAMDisk Image at 40200000 ...
4041 Image Name: Simple Ramdisk Image
4042 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4043 Data Size: 566530 Bytes = 553 kB = 0 MB
4044 Load Address: 00000000
4045 Entry Point: 00000000
4046 Verifying Checksum ... OK
4047 Loading Ramdisk ... OK
4048 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
4049 Boot arguments: root=/dev/ram
4050 time_init: decrementer frequency = 187500000/60
4051 Calibrating delay loop... 49.77 BogoMIPS
4053 RAMDISK: Compressed image found at block 0
4054 VFS: Mounted root (ext2 filesystem).
4058 Boot Linux and pass a flat device tree:
4061 First, U-Boot must be compiled with the appropriate defines. See the section
4062 titled "Linux Kernel Interface" above for a more in depth explanation. The
4063 following is an example of how to start a kernel and pass an updated
4069 oft=oftrees/mpc8540ads.dtb
4070 => tftp $oftaddr $oft
4071 Speed: 1000, full duplex
4073 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4074 Filename 'oftrees/mpc8540ads.dtb'.
4075 Load address: 0x300000
4078 Bytes transferred = 4106 (100a hex)
4079 => tftp $loadaddr $bootfile
4080 Speed: 1000, full duplex
4082 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4084 Load address: 0x200000
4085 Loading:############
4087 Bytes transferred = 1029407 (fb51f hex)
4092 => bootm $loadaddr - $oftaddr
4093 ## Booting image at 00200000 ...
4094 Image Name: Linux-2.6.17-dirty
4095 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4096 Data Size: 1029343 Bytes = 1005.2 kB
4097 Load Address: 00000000
4098 Entry Point: 00000000
4099 Verifying Checksum ... OK
4100 Uncompressing Kernel Image ... OK
4101 Booting using flat device tree at 0x300000
4102 Using MPC85xx ADS machine description
4103 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4107 More About U-Boot Image Types:
4108 ------------------------------
4110 U-Boot supports the following image types:
4112 "Standalone Programs" are directly runnable in the environment
4113 provided by U-Boot; it is expected that (if they behave
4114 well) you can continue to work in U-Boot after return from
4115 the Standalone Program.
4116 "OS Kernel Images" are usually images of some Embedded OS which
4117 will take over control completely. Usually these programs
4118 will install their own set of exception handlers, device
4119 drivers, set up the MMU, etc. - this means, that you cannot
4120 expect to re-enter U-Boot except by resetting the CPU.
4121 "RAMDisk Images" are more or less just data blocks, and their
4122 parameters (address, size) are passed to an OS kernel that is
4124 "Multi-File Images" contain several images, typically an OS
4125 (Linux) kernel image and one or more data images like
4126 RAMDisks. This construct is useful for instance when you want
4127 to boot over the network using BOOTP etc., where the boot
4128 server provides just a single image file, but you want to get
4129 for instance an OS kernel and a RAMDisk image.
4131 "Multi-File Images" start with a list of image sizes, each
4132 image size (in bytes) specified by an "uint32_t" in network
4133 byte order. This list is terminated by an "(uint32_t)0".
4134 Immediately after the terminating 0 follow the images, one by
4135 one, all aligned on "uint32_t" boundaries (size rounded up to
4136 a multiple of 4 bytes).
4138 "Firmware Images" are binary images containing firmware (like
4139 U-Boot or FPGA images) which usually will be programmed to
4142 "Script files" are command sequences that will be executed by
4143 U-Boot's command interpreter; this feature is especially
4144 useful when you configure U-Boot to use a real shell (hush)
4145 as command interpreter.
4151 One of the features of U-Boot is that you can dynamically load and
4152 run "standalone" applications, which can use some resources of
4153 U-Boot like console I/O functions or interrupt services.
4155 Two simple examples are included with the sources:
4160 'examples/hello_world.c' contains a small "Hello World" Demo
4161 application; it is automatically compiled when you build U-Boot.
4162 It's configured to run at address 0x00040004, so you can play with it
4166 ## Ready for S-Record download ...
4167 ~>examples/hello_world.srec
4168 1 2 3 4 5 6 7 8 9 10 11 ...
4169 [file transfer complete]
4171 ## Start Addr = 0x00040004
4173 => go 40004 Hello World! This is a test.
4174 ## Starting application at 0x00040004 ...
4185 Hit any key to exit ...
4187 ## Application terminated, rc = 0x0
4189 Another example, which demonstrates how to register a CPM interrupt
4190 handler with the U-Boot code, can be found in 'examples/timer.c'.
4191 Here, a CPM timer is set up to generate an interrupt every second.
4192 The interrupt service routine is trivial, just printing a '.'
4193 character, but this is just a demo program. The application can be
4194 controlled by the following keys:
4196 ? - print current values og the CPM Timer registers
4197 b - enable interrupts and start timer
4198 e - stop timer and disable interrupts
4199 q - quit application
4202 ## Ready for S-Record download ...
4203 ~>examples/timer.srec
4204 1 2 3 4 5 6 7 8 9 10 11 ...
4205 [file transfer complete]
4207 ## Start Addr = 0x00040004
4210 ## Starting application at 0x00040004 ...
4213 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4216 [q, b, e, ?] Set interval 1000000 us
4219 [q, b, e, ?] ........
4220 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4223 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4226 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4229 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4231 [q, b, e, ?] ...Stopping timer
4233 [q, b, e, ?] ## Application terminated, rc = 0x0
4239 Over time, many people have reported problems when trying to use the
4240 "minicom" terminal emulation program for serial download. I (wd)
4241 consider minicom to be broken, and recommend not to use it. Under
4242 Unix, I recommend to use C-Kermit for general purpose use (and
4243 especially for kermit binary protocol download ("loadb" command), and
4244 use "cu" for S-Record download ("loads" command).
4246 Nevertheless, if you absolutely want to use it try adding this
4247 configuration to your "File transfer protocols" section:
4249 Name Program Name U/D FullScr IO-Red. Multi
4250 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4251 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4257 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4258 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4260 Building requires a cross environment; it is known to work on
4261 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4262 need gmake since the Makefiles are not compatible with BSD make).
4263 Note that the cross-powerpc package does not install include files;
4264 attempting to build U-Boot will fail because <machine/ansi.h> is
4265 missing. This file has to be installed and patched manually:
4267 # cd /usr/pkg/cross/powerpc-netbsd/include
4269 # ln -s powerpc machine
4270 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4271 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4273 Native builds *don't* work due to incompatibilities between native
4274 and U-Boot include files.
4276 Booting assumes that (the first part of) the image booted is a
4277 stage-2 loader which in turn loads and then invokes the kernel
4278 proper. Loader sources will eventually appear in the NetBSD source
4279 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4280 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4283 Implementation Internals:
4284 =========================
4286 The following is not intended to be a complete description of every
4287 implementation detail. However, it should help to understand the
4288 inner workings of U-Boot and make it easier to port it to custom
4292 Initial Stack, Global Data:
4293 ---------------------------
4295 The implementation of U-Boot is complicated by the fact that U-Boot
4296 starts running out of ROM (flash memory), usually without access to
4297 system RAM (because the memory controller is not initialized yet).
4298 This means that we don't have writable Data or BSS segments, and BSS
4299 is not initialized as zero. To be able to get a C environment working
4300 at all, we have to allocate at least a minimal stack. Implementation
4301 options for this are defined and restricted by the CPU used: Some CPU
4302 models provide on-chip memory (like the IMMR area on MPC8xx and
4303 MPC826x processors), on others (parts of) the data cache can be
4304 locked as (mis-) used as memory, etc.
4306 Chris Hallinan posted a good summary of these issues to the
4307 U-Boot mailing list:
4309 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4310 From: "Chris Hallinan" <clh@net1plus.com>
4311 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4314 Correct me if I'm wrong, folks, but the way I understand it
4315 is this: Using DCACHE as initial RAM for Stack, etc, does not
4316 require any physical RAM backing up the cache. The cleverness
4317 is that the cache is being used as a temporary supply of
4318 necessary storage before the SDRAM controller is setup. It's
4319 beyond the scope of this list to explain the details, but you
4320 can see how this works by studying the cache architecture and
4321 operation in the architecture and processor-specific manuals.
4323 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4324 is another option for the system designer to use as an
4325 initial stack/RAM area prior to SDRAM being available. Either
4326 option should work for you. Using CS 4 should be fine if your
4327 board designers haven't used it for something that would
4328 cause you grief during the initial boot! It is frequently not
4331 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4332 with your processor/board/system design. The default value
4333 you will find in any recent u-boot distribution in
4334 walnut.h should work for you. I'd set it to a value larger
4335 than your SDRAM module. If you have a 64MB SDRAM module, set
4336 it above 400_0000. Just make sure your board has no resources
4337 that are supposed to respond to that address! That code in
4338 start.S has been around a while and should work as is when
4339 you get the config right.
4344 It is essential to remember this, since it has some impact on the C
4345 code for the initialization procedures:
4347 * Initialized global data (data segment) is read-only. Do not attempt
4350 * Do not use any uninitialized global data (or implicitely initialized
4351 as zero data - BSS segment) at all - this is undefined, initiali-
4352 zation is performed later (when relocating to RAM).
4354 * Stack space is very limited. Avoid big data buffers or things like
4357 Having only the stack as writable memory limits means we cannot use
4358 normal global data to share information beween the code. But it
4359 turned out that the implementation of U-Boot can be greatly
4360 simplified by making a global data structure (gd_t) available to all
4361 functions. We could pass a pointer to this data as argument to _all_
4362 functions, but this would bloat the code. Instead we use a feature of
4363 the GCC compiler (Global Register Variables) to share the data: we
4364 place a pointer (gd) to the global data into a register which we
4365 reserve for this purpose.
4367 When choosing a register for such a purpose we are restricted by the
4368 relevant (E)ABI specifications for the current architecture, and by
4369 GCC's implementation.
4371 For PowerPC, the following registers have specific use:
4373 R2: reserved for system use
4374 R3-R4: parameter passing and return values
4375 R5-R10: parameter passing
4376 R13: small data area pointer
4380 (U-Boot also uses R12 as internal GOT pointer. r12
4381 is a volatile register so r12 needs to be reset when
4382 going back and forth between asm and C)
4384 ==> U-Boot will use R2 to hold a pointer to the global data
4386 Note: on PPC, we could use a static initializer (since the
4387 address of the global data structure is known at compile time),
4388 but it turned out that reserving a register results in somewhat
4389 smaller code - although the code savings are not that big (on
4390 average for all boards 752 bytes for the whole U-Boot image,
4391 624 text + 127 data).
4393 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4394 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4396 ==> U-Boot will use P3 to hold a pointer to the global data
4398 On ARM, the following registers are used:
4400 R0: function argument word/integer result
4401 R1-R3: function argument word
4403 R10: stack limit (used only if stack checking if enabled)
4404 R11: argument (frame) pointer
4405 R12: temporary workspace
4408 R15: program counter
4410 ==> U-Boot will use R8 to hold a pointer to the global data
4412 On Nios II, the ABI is documented here:
4413 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4415 ==> U-Boot will use gp to hold a pointer to the global data
4417 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4418 to access small data sections, so gp is free.
4420 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4421 or current versions of GCC may "optimize" the code too much.
4426 U-Boot runs in system state and uses physical addresses, i.e. the
4427 MMU is not used either for address mapping nor for memory protection.
4429 The available memory is mapped to fixed addresses using the memory
4430 controller. In this process, a contiguous block is formed for each
4431 memory type (Flash, SDRAM, SRAM), even when it consists of several
4432 physical memory banks.
4434 U-Boot is installed in the first 128 kB of the first Flash bank (on
4435 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4436 booting and sizing and initializing DRAM, the code relocates itself
4437 to the upper end of DRAM. Immediately below the U-Boot code some
4438 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4439 configuration setting]. Below that, a structure with global Board
4440 Info data is placed, followed by the stack (growing downward).
4442 Additionally, some exception handler code is copied to the low 8 kB
4443 of DRAM (0x00000000 ... 0x00001FFF).
4445 So a typical memory configuration with 16 MB of DRAM could look like
4448 0x0000 0000 Exception Vector code
4451 0x0000 2000 Free for Application Use
4457 0x00FB FF20 Monitor Stack (Growing downward)
4458 0x00FB FFAC Board Info Data and permanent copy of global data
4459 0x00FC 0000 Malloc Arena
4462 0x00FE 0000 RAM Copy of Monitor Code
4463 ... eventually: LCD or video framebuffer
4464 ... eventually: pRAM (Protected RAM - unchanged by reset)
4465 0x00FF FFFF [End of RAM]
4468 System Initialization:
4469 ----------------------
4471 In the reset configuration, U-Boot starts at the reset entry point
4472 (on most PowerPC systems at address 0x00000100). Because of the reset
4473 configuration for CS0# this is a mirror of the onboard Flash memory.
4474 To be able to re-map memory U-Boot then jumps to its link address.
4475 To be able to implement the initialization code in C, a (small!)
4476 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4477 which provide such a feature like MPC8xx or MPC8260), or in a locked
4478 part of the data cache. After that, U-Boot initializes the CPU core,
4479 the caches and the SIU.
4481 Next, all (potentially) available memory banks are mapped using a
4482 preliminary mapping. For example, we put them on 512 MB boundaries
4483 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4484 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4485 programmed for SDRAM access. Using the temporary configuration, a
4486 simple memory test is run that determines the size of the SDRAM
4489 When there is more than one SDRAM bank, and the banks are of
4490 different size, the largest is mapped first. For equal size, the first
4491 bank (CS2#) is mapped first. The first mapping is always for address
4492 0x00000000, with any additional banks following immediately to create
4493 contiguous memory starting from 0.
4495 Then, the monitor installs itself at the upper end of the SDRAM area
4496 and allocates memory for use by malloc() and for the global Board
4497 Info data; also, the exception vector code is copied to the low RAM
4498 pages, and the final stack is set up.
4500 Only after this relocation will you have a "normal" C environment;
4501 until that you are restricted in several ways, mostly because you are
4502 running from ROM, and because the code will have to be relocated to a
4506 U-Boot Porting Guide:
4507 ----------------------
4509 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4513 int main(int argc, char *argv[])
4515 sighandler_t no_more_time;
4517 signal(SIGALRM, no_more_time);
4518 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4520 if (available_money > available_manpower) {
4521 Pay consultant to port U-Boot;
4525 Download latest U-Boot source;
4527 Subscribe to u-boot mailing list;
4530 email("Hi, I am new to U-Boot, how do I get started?");
4533 Read the README file in the top level directory;
4534 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4535 Read applicable doc/*.README;
4536 Read the source, Luke;
4537 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4540 if (available_money > toLocalCurrency ($2500))
4543 Add a lot of aggravation and time;
4545 if (a similar board exists) { /* hopefully... */
4546 cp -a board/<similar> board/<myboard>
4547 cp include/configs/<similar>.h include/configs/<myboard>.h
4549 Create your own board support subdirectory;
4550 Create your own board include/configs/<myboard>.h file;
4552 Edit new board/<myboard> files
4553 Edit new include/configs/<myboard>.h
4558 Add / modify source code;
4562 email("Hi, I am having problems...");
4564 Send patch file to the U-Boot email list;
4565 if (reasonable critiques)
4566 Incorporate improvements from email list code review;
4568 Defend code as written;
4574 void no_more_time (int sig)
4583 All contributions to U-Boot should conform to the Linux kernel
4584 coding style; see the file "Documentation/CodingStyle" and the script
4585 "scripts/Lindent" in your Linux kernel source directory.
4587 Source files originating from a different project (for example the
4588 MTD subsystem) are generally exempt from these guidelines and are not
4589 reformated to ease subsequent migration to newer versions of those
4592 Please note that U-Boot is implemented in C (and to some small parts in
4593 Assembler); no C++ is used, so please do not use C++ style comments (//)
4596 Please also stick to the following formatting rules:
4597 - remove any trailing white space
4598 - use TAB characters for indentation and vertical alignment, not spaces
4599 - make sure NOT to use DOS '\r\n' line feeds
4600 - do not add more than 2 consecutive empty lines to source files
4601 - do not add trailing empty lines to source files
4603 Submissions which do not conform to the standards may be returned
4604 with a request to reformat the changes.
4610 Since the number of patches for U-Boot is growing, we need to
4611 establish some rules. Submissions which do not conform to these rules
4612 may be rejected, even when they contain important and valuable stuff.
4614 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4616 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4617 see http://lists.denx.de/mailman/listinfo/u-boot
4619 When you send a patch, please include the following information with
4622 * For bug fixes: a description of the bug and how your patch fixes
4623 this bug. Please try to include a way of demonstrating that the
4624 patch actually fixes something.
4626 * For new features: a description of the feature and your
4629 * A CHANGELOG entry as plaintext (separate from the patch)
4631 * For major contributions, your entry to the CREDITS file
4633 * When you add support for a new board, don't forget to add this
4634 board to the MAINTAINERS file, too.
4636 * If your patch adds new configuration options, don't forget to
4637 document these in the README file.
4639 * The patch itself. If you are using git (which is *strongly*
4640 recommended) you can easily generate the patch using the
4641 "git format-patch". If you then use "git send-email" to send it to
4642 the U-Boot mailing list, you will avoid most of the common problems
4643 with some other mail clients.
4645 If you cannot use git, use "diff -purN OLD NEW". If your version of
4646 diff does not support these options, then get the latest version of
4649 The current directory when running this command shall be the parent
4650 directory of the U-Boot source tree (i. e. please make sure that
4651 your patch includes sufficient directory information for the
4654 We prefer patches as plain text. MIME attachments are discouraged,
4655 and compressed attachments must not be used.
4657 * If one logical set of modifications affects or creates several
4658 files, all these changes shall be submitted in a SINGLE patch file.
4660 * Changesets that contain different, unrelated modifications shall be
4661 submitted as SEPARATE patches, one patch per changeset.
4666 * Before sending the patch, run the MAKEALL script on your patched
4667 source tree and make sure that no errors or warnings are reported
4668 for any of the boards.
4670 * Keep your modifications to the necessary minimum: A patch
4671 containing several unrelated changes or arbitrary reformats will be
4672 returned with a request to re-formatting / split it.
4674 * If you modify existing code, make sure that your new code does not
4675 add to the memory footprint of the code ;-) Small is beautiful!
4676 When adding new features, these should compile conditionally only
4677 (using #ifdef), and the resulting code with the new feature
4678 disabled must not need more memory than the old code without your
4681 * Remember that there is a size limit of 100 kB per message on the
4682 u-boot mailing list. Bigger patches will be moderated. If they are
4683 reasonable and not too big, they will be acknowledged. But patches
4684 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob