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 /at91rm9200 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 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
360 CONFIG_SYS_FSL_TBCLK_DIV
362 Defines the core time base clock divider ratio compared to the
363 system clock. On most PQ3 devices this is 8, on newer QorIQ
364 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366 CONFIG_SYS_FSL_PCIE_COMPAT
368 Defines the string to utilize when trying to match PCIe device
369 tree nodes for the given platform.
371 - Intel Monahans options:
372 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
374 Defines the Monahans run mode to oscillator
375 ratio. Valid values are 8, 16, 24, 31. The core
376 frequency is this value multiplied by 13 MHz.
378 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
380 Defines the Monahans turbo mode to oscillator
381 ratio. Valid values are 1 (default if undefined) and
382 2. The core frequency as calculated above is multiplied
385 - Linux Kernel Interface:
388 U-Boot stores all clock information in Hz
389 internally. For binary compatibility with older Linux
390 kernels (which expect the clocks passed in the
391 bd_info data to be in MHz) the environment variable
392 "clocks_in_mhz" can be defined so that U-Boot
393 converts clock data to MHZ before passing it to the
395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
396 "clocks_in_mhz=1" is automatically included in the
399 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
401 When transferring memsize parameter to linux, some versions
402 expect it to be in bytes, others in MB.
403 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
407 New kernel versions are expecting firmware settings to be
408 passed using flattened device trees (based on open firmware
412 * New libfdt-based support
413 * Adds the "fdt" command
414 * The bootm command automatically updates the fdt
416 OF_CPU - The proper name of the cpus node (only required for
417 MPC512X and MPC5xxx based boards).
418 OF_SOC - The proper name of the soc node (only required for
419 MPC512X and MPC5xxx based boards).
420 OF_TBCLK - The timebase frequency.
421 OF_STDOUT_PATH - The path to the console device
423 boards with QUICC Engines require OF_QE to set UCC MAC
426 CONFIG_OF_BOARD_SETUP
428 Board code has addition modification that it wants to make
429 to the flat device tree before handing it off to the kernel
433 This define fills in the correct boot CPU in the boot
434 param header, the default value is zero if undefined.
438 U-Boot can detect if an IDE device is present or not.
439 If not, and this new config option is activated, U-Boot
440 removes the ATA node from the DTS before booting Linux,
441 so the Linux IDE driver does not probe the device and
442 crash. This is needed for buggy hardware (uc101) where
443 no pull down resistor is connected to the signal IDE5V_DD7.
445 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
447 This setting is mandatory for all boards that have only one
448 machine type and must be used to specify the machine type
449 number as it appears in the ARM machine registry
450 (see http://www.arm.linux.org.uk/developer/machines/).
451 Only boards that have multiple machine types supported
452 in a single configuration file and the machine type is
453 runtime discoverable, do not have to use this setting.
455 - vxWorks boot parameters:
457 bootvx constructs a valid bootline using the following
458 environments variables: bootfile, ipaddr, serverip, hostname.
459 It loads the vxWorks image pointed bootfile.
461 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
462 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
463 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
464 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
466 CONFIG_SYS_VXWORKS_ADD_PARAMS
468 Add it at the end of the bootline. E.g "u=username pw=secret"
470 Note: If a "bootargs" environment is defined, it will overwride
471 the defaults discussed just above.
473 - Cache Configuration:
474 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
475 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
476 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
478 - Cache Configuration for ARM:
479 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
481 CONFIG_SYS_PL310_BASE - Physical base address of PL310
482 controller register space
487 Define this if you want support for Amba PrimeCell PL010 UARTs.
491 Define this if you want support for Amba PrimeCell PL011 UARTs.
495 If you have Amba PrimeCell PL011 UARTs, set this variable to
496 the clock speed of the UARTs.
500 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
501 define this to a list of base addresses for each (supported)
502 port. See e.g. include/configs/versatile.h
504 CONFIG_PL011_SERIAL_RLCR
506 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
507 have separate receive and transmit line control registers. Set
508 this variable to initialize the extra register.
510 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
512 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
513 boot loader that has already initialized the UART. Define this
514 variable to flush the UART at init time.
518 Depending on board, define exactly one serial port
519 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
520 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
521 console by defining CONFIG_8xx_CONS_NONE
523 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
524 port routines must be defined elsewhere
525 (i.e. serial_init(), serial_getc(), ...)
528 Enables console device for a color framebuffer. Needs following
529 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
530 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
532 VIDEO_HW_RECTFILL graphic chip supports
535 VIDEO_HW_BITBLT graphic chip supports
536 bit-blit (cf. smiLynxEM)
537 VIDEO_VISIBLE_COLS visible pixel columns
539 VIDEO_VISIBLE_ROWS visible pixel rows
540 VIDEO_PIXEL_SIZE bytes per pixel
541 VIDEO_DATA_FORMAT graphic data format
542 (0-5, cf. cfb_console.c)
543 VIDEO_FB_ADRS framebuffer address
544 VIDEO_KBD_INIT_FCT keyboard int fct
545 (i.e. i8042_kbd_init())
546 VIDEO_TSTC_FCT test char fct
548 VIDEO_GETC_FCT get char fct
550 CONFIG_CONSOLE_CURSOR cursor drawing on/off
551 (requires blink timer
553 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
554 CONFIG_CONSOLE_TIME display time/date info in
556 (requires CONFIG_CMD_DATE)
557 CONFIG_VIDEO_LOGO display Linux logo in
559 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
560 linux_logo.h for logo.
561 Requires CONFIG_VIDEO_LOGO
562 CONFIG_CONSOLE_EXTRA_INFO
563 additional board info beside
566 When CONFIG_CFB_CONSOLE is defined, video console is
567 default i/o. Serial console can be forced with
568 environment 'console=serial'.
570 When CONFIG_SILENT_CONSOLE is defined, all console
571 messages (by U-Boot and Linux!) can be silenced with
572 the "silent" environment variable. See
573 doc/README.silent for more information.
576 CONFIG_BAUDRATE - in bps
577 Select one of the baudrates listed in
578 CONFIG_SYS_BAUDRATE_TABLE, see below.
579 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
581 - Console Rx buffer length
582 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
583 the maximum receive buffer length for the SMC.
584 This option is actual only for 82xx and 8xx possible.
585 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
586 must be defined, to setup the maximum idle timeout for
589 - Boot Delay: CONFIG_BOOTDELAY - in seconds
590 Delay before automatically booting the default image;
591 set to -1 to disable autoboot.
593 See doc/README.autoboot for these options that
594 work with CONFIG_BOOTDELAY. None are required.
595 CONFIG_BOOT_RETRY_TIME
596 CONFIG_BOOT_RETRY_MIN
597 CONFIG_AUTOBOOT_KEYED
598 CONFIG_AUTOBOOT_PROMPT
599 CONFIG_AUTOBOOT_DELAY_STR
600 CONFIG_AUTOBOOT_STOP_STR
601 CONFIG_AUTOBOOT_DELAY_STR2
602 CONFIG_AUTOBOOT_STOP_STR2
603 CONFIG_ZERO_BOOTDELAY_CHECK
604 CONFIG_RESET_TO_RETRY
608 Only needed when CONFIG_BOOTDELAY is enabled;
609 define a command string that is automatically executed
610 when no character is read on the console interface
611 within "Boot Delay" after reset.
614 This can be used to pass arguments to the bootm
615 command. The value of CONFIG_BOOTARGS goes into the
616 environment value "bootargs".
618 CONFIG_RAMBOOT and CONFIG_NFSBOOT
619 The value of these goes into the environment as
620 "ramboot" and "nfsboot" respectively, and can be used
621 as a convenience, when switching between booting from
627 When this option is #defined, the existence of the
628 environment variable "preboot" will be checked
629 immediately before starting the CONFIG_BOOTDELAY
630 countdown and/or running the auto-boot command resp.
631 entering interactive mode.
633 This feature is especially useful when "preboot" is
634 automatically generated or modified. For an example
635 see the LWMON board specific code: here "preboot" is
636 modified when the user holds down a certain
637 combination of keys on the (special) keyboard when
640 - Serial Download Echo Mode:
642 If defined to 1, all characters received during a
643 serial download (using the "loads" command) are
644 echoed back. This might be needed by some terminal
645 emulations (like "cu"), but may as well just take
646 time on others. This setting #define's the initial
647 value of the "loads_echo" environment variable.
649 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
651 Select one of the baudrates listed in
652 CONFIG_SYS_BAUDRATE_TABLE, see below.
655 Monitor commands can be included or excluded
656 from the build by using the #include files
657 "config_cmd_all.h" and #undef'ing unwanted
658 commands, or using "config_cmd_default.h"
659 and augmenting with additional #define's
662 The default command configuration includes all commands
663 except those marked below with a "*".
665 CONFIG_CMD_ASKENV * ask for env variable
666 CONFIG_CMD_BDI bdinfo
667 CONFIG_CMD_BEDBUG * Include BedBug Debugger
668 CONFIG_CMD_BMP * BMP support
669 CONFIG_CMD_BSP * Board specific commands
670 CONFIG_CMD_BOOTD bootd
671 CONFIG_CMD_CACHE * icache, dcache
672 CONFIG_CMD_CONSOLE coninfo
673 CONFIG_CMD_CRC32 * crc32
674 CONFIG_CMD_DATE * support for RTC, date/time...
675 CONFIG_CMD_DHCP * DHCP support
676 CONFIG_CMD_DIAG * Diagnostics
677 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
678 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
679 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
680 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
681 CONFIG_CMD_DTT * Digital Therm and Thermostat
682 CONFIG_CMD_ECHO echo arguments
683 CONFIG_CMD_EDITENV edit env variable
684 CONFIG_CMD_EEPROM * EEPROM read/write support
685 CONFIG_CMD_ELF * bootelf, bootvx
686 CONFIG_CMD_EXPORTENV * export the environment
687 CONFIG_CMD_SAVEENV saveenv
688 CONFIG_CMD_FDC * Floppy Disk Support
689 CONFIG_CMD_FAT * FAT partition support
690 CONFIG_CMD_FDOS * Dos diskette Support
691 CONFIG_CMD_FLASH flinfo, erase, protect
692 CONFIG_CMD_FPGA FPGA device initialization support
693 CONFIG_CMD_GO * the 'go' command (exec code)
694 CONFIG_CMD_GREPENV * search environment
695 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
696 CONFIG_CMD_I2C * I2C serial bus support
697 CONFIG_CMD_IDE * IDE harddisk support
698 CONFIG_CMD_IMI iminfo
699 CONFIG_CMD_IMLS List all found images
700 CONFIG_CMD_IMMAP * IMMR dump support
701 CONFIG_CMD_IMPORTENV * import an environment
702 CONFIG_CMD_IRQ * irqinfo
703 CONFIG_CMD_ITEST Integer/string test of 2 values
704 CONFIG_CMD_JFFS2 * JFFS2 Support
705 CONFIG_CMD_KGDB * kgdb
706 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
707 CONFIG_CMD_LOADB loadb
708 CONFIG_CMD_LOADS loads
709 CONFIG_CMD_MD5SUM print md5 message digest
710 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
711 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
713 CONFIG_CMD_MISC Misc functions like sleep etc
714 CONFIG_CMD_MMC * MMC memory mapped support
715 CONFIG_CMD_MII * MII utility commands
716 CONFIG_CMD_MTDPARTS * MTD partition support
717 CONFIG_CMD_NAND * NAND support
718 CONFIG_CMD_NET bootp, tftpboot, rarpboot
719 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
720 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
721 CONFIG_CMD_PCI * pciinfo
722 CONFIG_CMD_PCMCIA * PCMCIA support
723 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
725 CONFIG_CMD_PORTIO * Port I/O
726 CONFIG_CMD_REGINFO * Register dump
727 CONFIG_CMD_RUN run command in env variable
728 CONFIG_CMD_SAVES * save S record dump
729 CONFIG_CMD_SCSI * SCSI Support
730 CONFIG_CMD_SDRAM * print SDRAM configuration information
731 (requires CONFIG_CMD_I2C)
732 CONFIG_CMD_SETGETDCR Support for DCR Register access
734 CONFIG_CMD_SHA1SUM print sha1 memory digest
735 (requires CONFIG_CMD_MEMORY)
736 CONFIG_CMD_SOURCE "source" command Support
737 CONFIG_CMD_SPI * SPI serial bus support
738 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
739 CONFIG_CMD_USB * USB support
740 CONFIG_CMD_CDP * Cisco Discover Protocol support
741 CONFIG_CMD_FSL * Microblaze FSL support
744 EXAMPLE: If you want all functions except of network
745 support you can write:
747 #include "config_cmd_all.h"
748 #undef CONFIG_CMD_NET
751 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
753 Note: Don't enable the "icache" and "dcache" commands
754 (configuration option CONFIG_CMD_CACHE) unless you know
755 what you (and your U-Boot users) are doing. Data
756 cache cannot be enabled on systems like the 8xx or
757 8260 (where accesses to the IMMR region must be
758 uncached), and it cannot be disabled on all other
759 systems where we (mis-) use the data cache to hold an
760 initial stack and some data.
763 XXX - this list needs to get updated!
767 If this variable is defined, it enables watchdog
768 support for the SoC. There must be support in the SoC
769 specific code for a watchdog. For the 8xx and 8260
770 CPUs, the SIU Watchdog feature is enabled in the SYPCR
771 register. When supported for a specific SoC is
772 available, then no further board specific code should
776 When using a watchdog circuitry external to the used
777 SoC, then define this variable and provide board
778 specific code for the "hw_watchdog_reset" function.
781 CONFIG_VERSION_VARIABLE
782 If this variable is defined, an environment variable
783 named "ver" is created by U-Boot showing the U-Boot
784 version as printed by the "version" command.
785 This variable is readonly.
789 When CONFIG_CMD_DATE is selected, the type of the RTC
790 has to be selected, too. Define exactly one of the
793 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
794 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
795 CONFIG_RTC_MC13783 - use MC13783 RTC
796 CONFIG_RTC_MC146818 - use MC146818 RTC
797 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
798 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
799 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
800 CONFIG_RTC_DS164x - use Dallas DS164x RTC
801 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
802 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
803 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
804 CONFIG_SYS_RV3029_TCR - enable trickle charger on
807 Note that if the RTC uses I2C, then the I2C interface
808 must also be configured. See I2C Support, below.
811 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
812 CONFIG_PCA953X_INFO - enable pca953x info command
814 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
815 chip-ngpio pairs that tell the PCA953X driver the number of
816 pins supported by a particular chip.
818 Note that if the GPIO device uses I2C, then the I2C interface
819 must also be configured. See I2C Support, below.
823 When CONFIG_TIMESTAMP is selected, the timestamp
824 (date and time) of an image is printed by image
825 commands like bootm or iminfo. This option is
826 automatically enabled when you select CONFIG_CMD_DATE .
829 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
830 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
832 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
833 CONFIG_CMD_SCSI) you must configure support for at
834 least one partition type as well.
837 CONFIG_IDE_RESET_ROUTINE - this is defined in several
838 board configurations files but used nowhere!
840 CONFIG_IDE_RESET - is this is defined, IDE Reset will
841 be performed by calling the function
842 ide_set_reset(int reset)
843 which has to be defined in a board specific file
848 Set this to enable ATAPI support.
853 Set this to enable support for disks larger than 137GB
854 Also look at CONFIG_SYS_64BIT_LBA.
855 Whithout these , LBA48 support uses 32bit variables and will 'only'
856 support disks up to 2.1TB.
858 CONFIG_SYS_64BIT_LBA:
859 When enabled, makes the IDE subsystem use 64bit sector addresses.
863 At the moment only there is only support for the
864 SYM53C8XX SCSI controller; define
865 CONFIG_SCSI_SYM53C8XX to enable it.
867 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
868 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
869 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
870 maximum numbers of LUNs, SCSI ID's and target
872 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
874 - NETWORK Support (PCI):
876 Support for Intel 8254x gigabit chips.
878 CONFIG_E1000_FALLBACK_MAC
879 default MAC for empty EEPROM after production.
882 Support for Intel 82557/82559/82559ER chips.
883 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
884 write routine for first time initialisation.
887 Support for Digital 2114x chips.
888 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
889 modem chip initialisation (KS8761/QS6611).
892 Support for National dp83815 chips.
895 Support for National dp8382[01] gigabit chips.
897 - NETWORK Support (other):
899 CONFIG_DRIVER_AT91EMAC
900 Support for AT91RM9200 EMAC.
903 Define this to use reduced MII inteface
905 CONFIG_DRIVER_AT91EMAC_QUIET
906 If this defined, the driver is quiet.
907 The driver doen't show link status messages.
909 CONFIG_DRIVER_LAN91C96
910 Support for SMSC's LAN91C96 chips.
913 Define this to hold the physical address
914 of the LAN91C96's I/O space
916 CONFIG_LAN91C96_USE_32_BIT
917 Define this to enable 32 bit addressing
919 CONFIG_DRIVER_SMC91111
920 Support for SMSC's LAN91C111 chip
923 Define this to hold the physical address
924 of the device (I/O space)
926 CONFIG_SMC_USE_32_BIT
927 Define this if data bus is 32 bits
929 CONFIG_SMC_USE_IOFUNCS
930 Define this to use i/o functions instead of macros
931 (some hardware wont work with macros)
934 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
936 CONFIG_FTGMAC100_EGIGA
937 Define this to use GE link update with gigabit PHY.
938 Define this if FTGMAC100 is connected to gigabit PHY.
939 If your system has 10/100 PHY only, it might not occur
940 wrong behavior. Because PHY usually return timeout or
941 useless data when polling gigabit status and gigabit
942 control registers. This behavior won't affect the
943 correctnessof 10/100 link speed update.
946 Support for SMSC's LAN911x and LAN921x chips
949 Define this to hold the physical address
950 of the device (I/O space)
952 CONFIG_SMC911X_32_BIT
953 Define this if data bus is 32 bits
955 CONFIG_SMC911X_16_BIT
956 Define this if data bus is 16 bits. If your processor
957 automatically converts one 32 bit word to two 16 bit
958 words you may also try CONFIG_SMC911X_32_BIT.
961 Support for Renesas on-chip Ethernet controller
963 CONFIG_SH_ETHER_USE_PORT
964 Define the number of ports to be used
966 CONFIG_SH_ETHER_PHY_ADDR
967 Define the ETH PHY's address
969 CONFIG_SH_ETHER_CACHE_WRITEBACK
970 If this option is set, the driver enables cache flush.
973 At the moment only the UHCI host controller is
974 supported (PIP405, MIP405, MPC5200); define
975 CONFIG_USB_UHCI to enable it.
976 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
977 and define CONFIG_USB_STORAGE to enable the USB
980 Supported are USB Keyboards and USB Floppy drives
982 MPC5200 USB requires additional defines:
984 for 528 MHz Clock: 0x0001bbbb
988 for differential drivers: 0x00001000
989 for single ended drivers: 0x00005000
990 for differential drivers on PSC3: 0x00000100
991 for single ended drivers on PSC3: 0x00004100
992 CONFIG_SYS_USB_EVENT_POLL
993 May be defined to allow interrupt polling
994 instead of using asynchronous interrupts
997 Define the below if you wish to use the USB console.
998 Once firmware is rebuilt from a serial console issue the
999 command "setenv stdin usbtty; setenv stdout usbtty" and
1000 attach your USB cable. The Unix command "dmesg" should print
1001 it has found a new device. The environment variable usbtty
1002 can be set to gserial or cdc_acm to enable your device to
1003 appear to a USB host as a Linux gserial device or a
1004 Common Device Class Abstract Control Model serial device.
1005 If you select usbtty = gserial you should be able to enumerate
1007 # modprobe usbserial vendor=0xVendorID product=0xProductID
1008 else if using cdc_acm, simply setting the environment
1009 variable usbtty to be cdc_acm should suffice. The following
1010 might be defined in YourBoardName.h
1013 Define this to build a UDC device
1016 Define this to have a tty type of device available to
1017 talk to the UDC device
1019 CONFIG_SYS_CONSOLE_IS_IN_ENV
1020 Define this if you want stdin, stdout &/or stderr to
1024 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1025 Derive USB clock from external clock "blah"
1026 - CONFIG_SYS_USB_EXTC_CLK 0x02
1028 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1029 Derive USB clock from brgclk
1030 - CONFIG_SYS_USB_BRG_CLK 0x04
1032 If you have a USB-IF assigned VendorID then you may wish to
1033 define your own vendor specific values either in BoardName.h
1034 or directly in usbd_vendor_info.h. If you don't define
1035 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1036 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1037 should pretend to be a Linux device to it's target host.
1039 CONFIG_USBD_MANUFACTURER
1040 Define this string as the name of your company for
1041 - CONFIG_USBD_MANUFACTURER "my company"
1043 CONFIG_USBD_PRODUCT_NAME
1044 Define this string as the name of your product
1045 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1047 CONFIG_USBD_VENDORID
1048 Define this as your assigned Vendor ID from the USB
1049 Implementors Forum. This *must* be a genuine Vendor ID
1050 to avoid polluting the USB namespace.
1051 - CONFIG_USBD_VENDORID 0xFFFF
1053 CONFIG_USBD_PRODUCTID
1054 Define this as the unique Product ID
1056 - CONFIG_USBD_PRODUCTID 0xFFFF
1060 The MMC controller on the Intel PXA is supported. To
1061 enable this define CONFIG_MMC. The MMC can be
1062 accessed from the boot prompt by mapping the device
1063 to physical memory similar to flash. Command line is
1064 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1065 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1067 - Journaling Flash filesystem support:
1068 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1069 CONFIG_JFFS2_NAND_DEV
1070 Define these for a default partition on a NAND device
1072 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1073 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1074 Define these for a default partition on a NOR device
1076 CONFIG_SYS_JFFS_CUSTOM_PART
1077 Define this to create an own partition. You have to provide a
1078 function struct part_info* jffs2_part_info(int part_num)
1080 If you define only one JFFS2 partition you may also want to
1081 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1082 to disable the command chpart. This is the default when you
1083 have not defined a custom partition
1088 Define this to enable standard (PC-Style) keyboard
1092 Standard PC keyboard driver with US (is default) and
1093 GERMAN key layout (switch via environment 'keymap=de') support.
1094 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1095 for cfb_console. Supports cursor blinking.
1100 Define this to enable video support (for output to
1103 CONFIG_VIDEO_CT69000
1105 Enable Chips & Technologies 69000 Video chip
1107 CONFIG_VIDEO_SMI_LYNXEM
1108 Enable Silicon Motion SMI 712/710/810 Video chip. The
1109 video output is selected via environment 'videoout'
1110 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1113 For the CT69000 and SMI_LYNXEM drivers, videomode is
1114 selected via environment 'videomode'. Two different ways
1116 - "videomode=num" 'num' is a standard LiLo mode numbers.
1117 Following standard modes are supported (* is default):
1119 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1120 -------------+---------------------------------------------
1121 8 bits | 0x301* 0x303 0x305 0x161 0x307
1122 15 bits | 0x310 0x313 0x316 0x162 0x319
1123 16 bits | 0x311 0x314 0x317 0x163 0x31A
1124 24 bits | 0x312 0x315 0x318 ? 0x31B
1125 -------------+---------------------------------------------
1126 (i.e. setenv videomode 317; saveenv; reset;)
1128 - "videomode=bootargs" all the video parameters are parsed
1129 from the bootargs. (See drivers/video/videomodes.c)
1132 CONFIG_VIDEO_SED13806
1133 Enable Epson SED13806 driver. This driver supports 8bpp
1134 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1135 or CONFIG_VIDEO_SED13806_16BPP
1138 Enable the Freescale DIU video driver. Reference boards for
1139 SOCs that have a DIU should define this macro to enable DIU
1140 support, and should also define these other macros:
1146 CONFIG_VIDEO_SW_CURSOR
1147 CONFIG_VGA_AS_SINGLE_DEVICE
1149 CONFIG_VIDEO_BMP_LOGO
1151 The DIU driver will look for the 'video-mode' environment
1152 variable, and if defined, enable the DIU as a console during
1153 boot. See the documentation file README.video for a
1154 description of this variable.
1159 Define this to enable a custom keyboard support.
1160 This simply calls drv_keyboard_init() which must be
1161 defined in your board-specific files.
1162 The only board using this so far is RBC823.
1164 - LCD Support: CONFIG_LCD
1166 Define this to enable LCD support (for output to LCD
1167 display); also select one of the supported displays
1168 by defining one of these:
1172 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1174 CONFIG_NEC_NL6448AC33:
1176 NEC NL6448AC33-18. Active, color, single scan.
1178 CONFIG_NEC_NL6448BC20
1180 NEC NL6448BC20-08. 6.5", 640x480.
1181 Active, color, single scan.
1183 CONFIG_NEC_NL6448BC33_54
1185 NEC NL6448BC33-54. 10.4", 640x480.
1186 Active, color, single scan.
1190 Sharp 320x240. Active, color, single scan.
1191 It isn't 16x9, and I am not sure what it is.
1193 CONFIG_SHARP_LQ64D341
1195 Sharp LQ64D341 display, 640x480.
1196 Active, color, single scan.
1200 HLD1045 display, 640x480.
1201 Active, color, single scan.
1205 Optrex CBL50840-2 NF-FW 99 22 M5
1207 Hitachi LMG6912RPFC-00T
1211 320x240. Black & white.
1213 Normally display is black on white background; define
1214 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1216 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1218 If this option is set, the environment is checked for
1219 a variable "splashimage". If found, the usual display
1220 of logo, copyright and system information on the LCD
1221 is suppressed and the BMP image at the address
1222 specified in "splashimage" is loaded instead. The
1223 console is redirected to the "nulldev", too. This
1224 allows for a "silent" boot where a splash screen is
1225 loaded very quickly after power-on.
1227 CONFIG_SPLASH_SCREEN_ALIGN
1229 If this option is set the splash image can be freely positioned
1230 on the screen. Environment variable "splashpos" specifies the
1231 position as "x,y". If a positive number is given it is used as
1232 number of pixel from left/top. If a negative number is given it
1233 is used as number of pixel from right/bottom. You can also
1234 specify 'm' for centering the image.
1237 setenv splashpos m,m
1238 => image at center of screen
1240 setenv splashpos 30,20
1241 => image at x = 30 and y = 20
1243 setenv splashpos -10,m
1244 => vertically centered image
1245 at x = dspWidth - bmpWidth - 9
1247 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1249 If this option is set, additionally to standard BMP
1250 images, gzipped BMP images can be displayed via the
1251 splashscreen support or the bmp command.
1253 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1255 If this option is set, 8-bit RLE compressed BMP images
1256 can be displayed via the splashscreen support or the
1259 - Compression support:
1262 If this option is set, support for bzip2 compressed
1263 images is included. If not, only uncompressed and gzip
1264 compressed images are supported.
1266 NOTE: the bzip2 algorithm requires a lot of RAM, so
1267 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1272 If this option is set, support for lzma compressed
1275 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1276 requires an amount of dynamic memory that is given by the
1279 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1281 Where lc and lp stand for, respectively, Literal context bits
1282 and Literal pos bits.
1284 This value is upper-bounded by 14MB in the worst case. Anyway,
1285 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1286 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1287 a very small buffer.
1289 Use the lzmainfo tool to determinate the lc and lp values and
1290 then calculate the amount of needed dynamic memory (ensuring
1291 the appropriate CONFIG_SYS_MALLOC_LEN value).
1296 The address of PHY on MII bus.
1298 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1300 The clock frequency of the MII bus
1304 If this option is set, support for speed/duplex
1305 detection of gigabit PHY is included.
1307 CONFIG_PHY_RESET_DELAY
1309 Some PHY like Intel LXT971A need extra delay after
1310 reset before any MII register access is possible.
1311 For such PHY, set this option to the usec delay
1312 required. (minimum 300usec for LXT971A)
1314 CONFIG_PHY_CMD_DELAY (ppc4xx)
1316 Some PHY like Intel LXT971A need extra delay after
1317 command issued before MII status register can be read
1327 Define a default value for Ethernet address to use
1328 for the respective Ethernet interface, in case this
1329 is not determined automatically.
1334 Define a default value for the IP address to use for
1335 the default Ethernet interface, in case this is not
1336 determined through e.g. bootp.
1338 - Server IP address:
1341 Defines a default value for the IP address of a TFTP
1342 server to contact when using the "tftboot" command.
1344 CONFIG_KEEP_SERVERADDR
1346 Keeps the server's MAC address, in the env 'serveraddr'
1347 for passing to bootargs (like Linux's netconsole option)
1349 - Multicast TFTP Mode:
1352 Defines whether you want to support multicast TFTP as per
1353 rfc-2090; for example to work with atftp. Lets lots of targets
1354 tftp down the same boot image concurrently. Note: the Ethernet
1355 driver in use must provide a function: mcast() to join/leave a
1358 - BOOTP Recovery Mode:
1359 CONFIG_BOOTP_RANDOM_DELAY
1361 If you have many targets in a network that try to
1362 boot using BOOTP, you may want to avoid that all
1363 systems send out BOOTP requests at precisely the same
1364 moment (which would happen for instance at recovery
1365 from a power failure, when all systems will try to
1366 boot, thus flooding the BOOTP server. Defining
1367 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1368 inserted before sending out BOOTP requests. The
1369 following delays are inserted then:
1371 1st BOOTP request: delay 0 ... 1 sec
1372 2nd BOOTP request: delay 0 ... 2 sec
1373 3rd BOOTP request: delay 0 ... 4 sec
1375 BOOTP requests: delay 0 ... 8 sec
1377 - DHCP Advanced Options:
1378 You can fine tune the DHCP functionality by defining
1379 CONFIG_BOOTP_* symbols:
1381 CONFIG_BOOTP_SUBNETMASK
1382 CONFIG_BOOTP_GATEWAY
1383 CONFIG_BOOTP_HOSTNAME
1384 CONFIG_BOOTP_NISDOMAIN
1385 CONFIG_BOOTP_BOOTPATH
1386 CONFIG_BOOTP_BOOTFILESIZE
1389 CONFIG_BOOTP_SEND_HOSTNAME
1390 CONFIG_BOOTP_NTPSERVER
1391 CONFIG_BOOTP_TIMEOFFSET
1392 CONFIG_BOOTP_VENDOREX
1394 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1395 environment variable, not the BOOTP server.
1397 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1398 serverip from a DHCP server, it is possible that more
1399 than one DNS serverip is offered to the client.
1400 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1401 serverip will be stored in the additional environment
1402 variable "dnsip2". The first DNS serverip is always
1403 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1406 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1407 to do a dynamic update of a DNS server. To do this, they
1408 need the hostname of the DHCP requester.
1409 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1410 of the "hostname" environment variable is passed as
1411 option 12 to the DHCP server.
1413 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1415 A 32bit value in microseconds for a delay between
1416 receiving a "DHCP Offer" and sending the "DHCP Request".
1417 This fixes a problem with certain DHCP servers that don't
1418 respond 100% of the time to a "DHCP request". E.g. On an
1419 AT91RM9200 processor running at 180MHz, this delay needed
1420 to be *at least* 15,000 usec before a Windows Server 2003
1421 DHCP server would reply 100% of the time. I recommend at
1422 least 50,000 usec to be safe. The alternative is to hope
1423 that one of the retries will be successful but note that
1424 the DHCP timeout and retry process takes a longer than
1428 CONFIG_CDP_DEVICE_ID
1430 The device id used in CDP trigger frames.
1432 CONFIG_CDP_DEVICE_ID_PREFIX
1434 A two character string which is prefixed to the MAC address
1439 A printf format string which contains the ascii name of
1440 the port. Normally is set to "eth%d" which sets
1441 eth0 for the first Ethernet, eth1 for the second etc.
1443 CONFIG_CDP_CAPABILITIES
1445 A 32bit integer which indicates the device capabilities;
1446 0x00000010 for a normal host which does not forwards.
1450 An ascii string containing the version of the software.
1454 An ascii string containing the name of the platform.
1458 A 32bit integer sent on the trigger.
1460 CONFIG_CDP_POWER_CONSUMPTION
1462 A 16bit integer containing the power consumption of the
1463 device in .1 of milliwatts.
1465 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1467 A byte containing the id of the VLAN.
1469 - Status LED: CONFIG_STATUS_LED
1471 Several configurations allow to display the current
1472 status using a LED. For instance, the LED will blink
1473 fast while running U-Boot code, stop blinking as
1474 soon as a reply to a BOOTP request was received, and
1475 start blinking slow once the Linux kernel is running
1476 (supported by a status LED driver in the Linux
1477 kernel). Defining CONFIG_STATUS_LED enables this
1480 - CAN Support: CONFIG_CAN_DRIVER
1482 Defining CONFIG_CAN_DRIVER enables CAN driver support
1483 on those systems that support this (optional)
1484 feature, like the TQM8xxL modules.
1486 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1488 These enable I2C serial bus commands. Defining either of
1489 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1490 include the appropriate I2C driver for the selected CPU.
1492 This will allow you to use i2c commands at the u-boot
1493 command line (as long as you set CONFIG_CMD_I2C in
1494 CONFIG_COMMANDS) and communicate with i2c based realtime
1495 clock chips. See common/cmd_i2c.c for a description of the
1496 command line interface.
1498 CONFIG_HARD_I2C selects a hardware I2C controller.
1500 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1501 bit-banging) driver instead of CPM or similar hardware
1504 There are several other quantities that must also be
1505 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1507 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1508 to be the frequency (in Hz) at which you wish your i2c bus
1509 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1510 the CPU's i2c node address).
1512 Now, the u-boot i2c code for the mpc8xx
1513 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1514 and so its address should therefore be cleared to 0 (See,
1515 eg, MPC823e User's Manual p.16-473). So, set
1516 CONFIG_SYS_I2C_SLAVE to 0.
1518 CONFIG_SYS_I2C_INIT_MPC5XXX
1520 When a board is reset during an i2c bus transfer
1521 chips might think that the current transfer is still
1522 in progress. Reset the slave devices by sending start
1523 commands until the slave device responds.
1525 That's all that's required for CONFIG_HARD_I2C.
1527 If you use the software i2c interface (CONFIG_SOFT_I2C)
1528 then the following macros need to be defined (examples are
1529 from include/configs/lwmon.h):
1533 (Optional). Any commands necessary to enable the I2C
1534 controller or configure ports.
1536 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1540 (Only for MPC8260 CPU). The I/O port to use (the code
1541 assumes both bits are on the same port). Valid values
1542 are 0..3 for ports A..D.
1546 The code necessary to make the I2C data line active
1547 (driven). If the data line is open collector, this
1550 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1554 The code necessary to make the I2C data line tri-stated
1555 (inactive). If the data line is open collector, this
1558 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1562 Code that returns TRUE if the I2C data line is high,
1565 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1569 If <bit> is TRUE, sets the I2C data line high. If it
1570 is FALSE, it clears it (low).
1572 eg: #define I2C_SDA(bit) \
1573 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1574 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1578 If <bit> is TRUE, sets the I2C clock line high. If it
1579 is FALSE, it clears it (low).
1581 eg: #define I2C_SCL(bit) \
1582 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1583 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1587 This delay is invoked four times per clock cycle so this
1588 controls the rate of data transfer. The data rate thus
1589 is 1 / (I2C_DELAY * 4). Often defined to be something
1592 #define I2C_DELAY udelay(2)
1594 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1596 If your arch supports the generic GPIO framework (asm/gpio.h),
1597 then you may alternatively define the two GPIOs that are to be
1598 used as SCL / SDA. Any of the previous I2C_xxx macros will
1599 have GPIO-based defaults assigned to them as appropriate.
1601 You should define these to the GPIO value as given directly to
1602 the generic GPIO functions.
1604 CONFIG_SYS_I2C_INIT_BOARD
1606 When a board is reset during an i2c bus transfer
1607 chips might think that the current transfer is still
1608 in progress. On some boards it is possible to access
1609 the i2c SCLK line directly, either by using the
1610 processor pin as a GPIO or by having a second pin
1611 connected to the bus. If this option is defined a
1612 custom i2c_init_board() routine in boards/xxx/board.c
1613 is run early in the boot sequence.
1615 CONFIG_SYS_I2C_BOARD_LATE_INIT
1617 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1618 defined a custom i2c_board_late_init() routine in
1619 boards/xxx/board.c is run AFTER the operations in i2c_init()
1620 is completed. This callpoint can be used to unreset i2c bus
1621 using CPU i2c controller register accesses for CPUs whose i2c
1622 controller provide such a method. It is called at the end of
1623 i2c_init() to allow i2c_init operations to setup the i2c bus
1624 controller on the CPU (e.g. setting bus speed & slave address).
1626 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1628 This option enables configuration of bi_iic_fast[] flags
1629 in u-boot bd_info structure based on u-boot environment
1630 variable "i2cfast". (see also i2cfast)
1632 CONFIG_I2C_MULTI_BUS
1634 This option allows the use of multiple I2C buses, each of which
1635 must have a controller. At any point in time, only one bus is
1636 active. To switch to a different bus, use the 'i2c dev' command.
1637 Note that bus numbering is zero-based.
1639 CONFIG_SYS_I2C_NOPROBES
1641 This option specifies a list of I2C devices that will be skipped
1642 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1643 is set, specify a list of bus-device pairs. Otherwise, specify
1644 a 1D array of device addresses
1647 #undef CONFIG_I2C_MULTI_BUS
1648 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1650 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1652 #define CONFIG_I2C_MULTI_BUS
1653 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1655 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1657 CONFIG_SYS_SPD_BUS_NUM
1659 If defined, then this indicates the I2C bus number for DDR SPD.
1660 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1662 CONFIG_SYS_RTC_BUS_NUM
1664 If defined, then this indicates the I2C bus number for the RTC.
1665 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1667 CONFIG_SYS_DTT_BUS_NUM
1669 If defined, then this indicates the I2C bus number for the DTT.
1670 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1672 CONFIG_SYS_I2C_DTT_ADDR:
1674 If defined, specifies the I2C address of the DTT device.
1675 If not defined, then U-Boot uses predefined value for
1676 specified DTT device.
1680 Define this option if you want to use Freescale's I2C driver in
1681 drivers/i2c/fsl_i2c.c.
1685 Define this option if you have I2C devices reached over 1 .. n
1686 I2C Muxes like the pca9544a. This option addes a new I2C
1687 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1688 new I2C Bus to the existing I2C Busses. If you select the
1689 new Bus with "i2c dev", u-bbot sends first the commandos for
1690 the muxes to activate this new "bus".
1692 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1696 Adding a new I2C Bus reached over 2 pca9544a muxes
1697 The First mux with address 70 and channel 6
1698 The Second mux with address 71 and channel 4
1700 => i2c bus pca9544a:70:6:pca9544a:71:4
1702 Use the "i2c bus" command without parameter, to get a list
1703 of I2C Busses with muxes:
1706 Busses reached over muxes:
1708 reached over Mux(es):
1711 reached over Mux(es):
1716 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1717 u-boot sends First the Commando to the mux@70 to enable
1718 channel 6, and then the Commando to the mux@71 to enable
1721 After that, you can use the "normal" i2c commands as
1722 usual, to communicate with your I2C devices behind
1725 This option is actually implemented for the bitbanging
1726 algorithm in common/soft_i2c.c and for the Hardware I2C
1727 Bus on the MPC8260. But it should be not so difficult
1728 to add this option to other architectures.
1730 CONFIG_SOFT_I2C_READ_REPEATED_START
1732 defining this will force the i2c_read() function in
1733 the soft_i2c driver to perform an I2C repeated start
1734 between writing the address pointer and reading the
1735 data. If this define is omitted the default behaviour
1736 of doing a stop-start sequence will be used. Most I2C
1737 devices can use either method, but some require one or
1740 - SPI Support: CONFIG_SPI
1742 Enables SPI driver (so far only tested with
1743 SPI EEPROM, also an instance works with Crystal A/D and
1744 D/As on the SACSng board)
1748 Enables the driver for SPI controller on SuperH. Currently
1749 only SH7757 is supported.
1753 Enables extended (16-bit) SPI EEPROM addressing.
1754 (symmetrical to CONFIG_I2C_X)
1758 Enables a software (bit-bang) SPI driver rather than
1759 using hardware support. This is a general purpose
1760 driver that only requires three general I/O port pins
1761 (two outputs, one input) to function. If this is
1762 defined, the board configuration must define several
1763 SPI configuration items (port pins to use, etc). For
1764 an example, see include/configs/sacsng.h.
1768 Enables a hardware SPI driver for general-purpose reads
1769 and writes. As with CONFIG_SOFT_SPI, the board configuration
1770 must define a list of chip-select function pointers.
1771 Currently supported on some MPC8xxx processors. For an
1772 example, see include/configs/mpc8349emds.h.
1776 Enables the driver for the SPI controllers on i.MX and MXC
1777 SoCs. Currently only i.MX31 is supported.
1779 - FPGA Support: CONFIG_FPGA
1781 Enables FPGA subsystem.
1783 CONFIG_FPGA_<vendor>
1785 Enables support for specific chip vendors.
1788 CONFIG_FPGA_<family>
1790 Enables support for FPGA family.
1791 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1795 Specify the number of FPGA devices to support.
1797 CONFIG_SYS_FPGA_PROG_FEEDBACK
1799 Enable printing of hash marks during FPGA configuration.
1801 CONFIG_SYS_FPGA_CHECK_BUSY
1803 Enable checks on FPGA configuration interface busy
1804 status by the configuration function. This option
1805 will require a board or device specific function to
1810 If defined, a function that provides delays in the FPGA
1811 configuration driver.
1813 CONFIG_SYS_FPGA_CHECK_CTRLC
1814 Allow Control-C to interrupt FPGA configuration
1816 CONFIG_SYS_FPGA_CHECK_ERROR
1818 Check for configuration errors during FPGA bitfile
1819 loading. For example, abort during Virtex II
1820 configuration if the INIT_B line goes low (which
1821 indicated a CRC error).
1823 CONFIG_SYS_FPGA_WAIT_INIT
1825 Maximum time to wait for the INIT_B line to deassert
1826 after PROB_B has been deasserted during a Virtex II
1827 FPGA configuration sequence. The default time is 500
1830 CONFIG_SYS_FPGA_WAIT_BUSY
1832 Maximum time to wait for BUSY to deassert during
1833 Virtex II FPGA configuration. The default is 5 ms.
1835 CONFIG_SYS_FPGA_WAIT_CONFIG
1837 Time to wait after FPGA configuration. The default is
1840 - Configuration Management:
1843 If defined, this string will be added to the U-Boot
1844 version information (U_BOOT_VERSION)
1846 - Vendor Parameter Protection:
1848 U-Boot considers the values of the environment
1849 variables "serial#" (Board Serial Number) and
1850 "ethaddr" (Ethernet Address) to be parameters that
1851 are set once by the board vendor / manufacturer, and
1852 protects these variables from casual modification by
1853 the user. Once set, these variables are read-only,
1854 and write or delete attempts are rejected. You can
1855 change this behaviour:
1857 If CONFIG_ENV_OVERWRITE is #defined in your config
1858 file, the write protection for vendor parameters is
1859 completely disabled. Anybody can change or delete
1862 Alternatively, if you #define _both_ CONFIG_ETHADDR
1863 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1864 Ethernet address is installed in the environment,
1865 which can be changed exactly ONCE by the user. [The
1866 serial# is unaffected by this, i. e. it remains
1872 Define this variable to enable the reservation of
1873 "protected RAM", i. e. RAM which is not overwritten
1874 by U-Boot. Define CONFIG_PRAM to hold the number of
1875 kB you want to reserve for pRAM. You can overwrite
1876 this default value by defining an environment
1877 variable "pram" to the number of kB you want to
1878 reserve. Note that the board info structure will
1879 still show the full amount of RAM. If pRAM is
1880 reserved, a new environment variable "mem" will
1881 automatically be defined to hold the amount of
1882 remaining RAM in a form that can be passed as boot
1883 argument to Linux, for instance like that:
1885 setenv bootargs ... mem=\${mem}
1888 This way you can tell Linux not to use this memory,
1889 either, which results in a memory region that will
1890 not be affected by reboots.
1892 *WARNING* If your board configuration uses automatic
1893 detection of the RAM size, you must make sure that
1894 this memory test is non-destructive. So far, the
1895 following board configurations are known to be
1898 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1899 HERMES, IP860, RPXlite, LWMON, LANTEC,
1905 Define this variable to stop the system in case of a
1906 fatal error, so that you have to reset it manually.
1907 This is probably NOT a good idea for an embedded
1908 system where you want the system to reboot
1909 automatically as fast as possible, but it may be
1910 useful during development since you can try to debug
1911 the conditions that lead to the situation.
1913 CONFIG_NET_RETRY_COUNT
1915 This variable defines the number of retries for
1916 network operations like ARP, RARP, TFTP, or BOOTP
1917 before giving up the operation. If not defined, a
1918 default value of 5 is used.
1922 Timeout waiting for an ARP reply in milliseconds.
1924 - Command Interpreter:
1925 CONFIG_AUTO_COMPLETE
1927 Enable auto completion of commands using TAB.
1929 Note that this feature has NOT been implemented yet
1930 for the "hush" shell.
1933 CONFIG_SYS_HUSH_PARSER
1935 Define this variable to enable the "hush" shell (from
1936 Busybox) as command line interpreter, thus enabling
1937 powerful command line syntax like
1938 if...then...else...fi conditionals or `&&' and '||'
1939 constructs ("shell scripts").
1941 If undefined, you get the old, much simpler behaviour
1942 with a somewhat smaller memory footprint.
1945 CONFIG_SYS_PROMPT_HUSH_PS2
1947 This defines the secondary prompt string, which is
1948 printed when the command interpreter needs more input
1949 to complete a command. Usually "> ".
1953 In the current implementation, the local variables
1954 space and global environment variables space are
1955 separated. Local variables are those you define by
1956 simply typing `name=value'. To access a local
1957 variable later on, you have write `$name' or
1958 `${name}'; to execute the contents of a variable
1959 directly type `$name' at the command prompt.
1961 Global environment variables are those you use
1962 setenv/printenv to work with. To run a command stored
1963 in such a variable, you need to use the run command,
1964 and you must not use the '$' sign to access them.
1966 To store commands and special characters in a
1967 variable, please use double quotation marks
1968 surrounding the whole text of the variable, instead
1969 of the backslashes before semicolons and special
1972 - Commandline Editing and History:
1973 CONFIG_CMDLINE_EDITING
1975 Enable editing and History functions for interactive
1976 commandline input operations
1978 - Default Environment:
1979 CONFIG_EXTRA_ENV_SETTINGS
1981 Define this to contain any number of null terminated
1982 strings (variable = value pairs) that will be part of
1983 the default environment compiled into the boot image.
1985 For example, place something like this in your
1986 board's config file:
1988 #define CONFIG_EXTRA_ENV_SETTINGS \
1992 Warning: This method is based on knowledge about the
1993 internal format how the environment is stored by the
1994 U-Boot code. This is NOT an official, exported
1995 interface! Although it is unlikely that this format
1996 will change soon, there is no guarantee either.
1997 You better know what you are doing here.
1999 Note: overly (ab)use of the default environment is
2000 discouraged. Make sure to check other ways to preset
2001 the environment like the "source" command or the
2004 - DataFlash Support:
2005 CONFIG_HAS_DATAFLASH
2007 Defining this option enables DataFlash features and
2008 allows to read/write in Dataflash via the standard
2011 - SystemACE Support:
2014 Adding this option adds support for Xilinx SystemACE
2015 chips attached via some sort of local bus. The address
2016 of the chip must also be defined in the
2017 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2019 #define CONFIG_SYSTEMACE
2020 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2022 When SystemACE support is added, the "ace" device type
2023 becomes available to the fat commands, i.e. fatls.
2025 - TFTP Fixed UDP Port:
2028 If this is defined, the environment variable tftpsrcp
2029 is used to supply the TFTP UDP source port value.
2030 If tftpsrcp isn't defined, the normal pseudo-random port
2031 number generator is used.
2033 Also, the environment variable tftpdstp is used to supply
2034 the TFTP UDP destination port value. If tftpdstp isn't
2035 defined, the normal port 69 is used.
2037 The purpose for tftpsrcp is to allow a TFTP server to
2038 blindly start the TFTP transfer using the pre-configured
2039 target IP address and UDP port. This has the effect of
2040 "punching through" the (Windows XP) firewall, allowing
2041 the remainder of the TFTP transfer to proceed normally.
2042 A better solution is to properly configure the firewall,
2043 but sometimes that is not allowed.
2045 - Show boot progress:
2046 CONFIG_SHOW_BOOT_PROGRESS
2048 Defining this option allows to add some board-
2049 specific code (calling a user-provided function
2050 "show_boot_progress(int)") that enables you to show
2051 the system's boot progress on some display (for
2052 example, some LED's) on your board. At the moment,
2053 the following checkpoints are implemented:
2055 - Standalone program support:
2056 CONFIG_STANDALONE_LOAD_ADDR
2058 This option allows to define board specific values
2059 for the address where standalone program gets loaded,
2060 thus overwriting the architecutre dependent default
2063 - Frame Buffer Address:
2066 Define CONFIG_FB_ADDR if you want to use specific address for
2068 Then system will reserve the frame buffer address to defined address
2069 instead of lcd_setmem (this function grab the memory for frame buffer
2072 Please see board_init_f function.
2074 If you want this config option then,
2075 please define it at your board config file
2077 Legacy uImage format:
2080 1 common/cmd_bootm.c before attempting to boot an image
2081 -1 common/cmd_bootm.c Image header has bad magic number
2082 2 common/cmd_bootm.c Image header has correct magic number
2083 -2 common/cmd_bootm.c Image header has bad checksum
2084 3 common/cmd_bootm.c Image header has correct checksum
2085 -3 common/cmd_bootm.c Image data has bad checksum
2086 4 common/cmd_bootm.c Image data has correct checksum
2087 -4 common/cmd_bootm.c Image is for unsupported architecture
2088 5 common/cmd_bootm.c Architecture check OK
2089 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2090 6 common/cmd_bootm.c Image Type check OK
2091 -6 common/cmd_bootm.c gunzip uncompression error
2092 -7 common/cmd_bootm.c Unimplemented compression type
2093 7 common/cmd_bootm.c Uncompression OK
2094 8 common/cmd_bootm.c No uncompress/copy overwrite error
2095 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2097 9 common/image.c Start initial ramdisk verification
2098 -10 common/image.c Ramdisk header has bad magic number
2099 -11 common/image.c Ramdisk header has bad checksum
2100 10 common/image.c Ramdisk header is OK
2101 -12 common/image.c Ramdisk data has bad checksum
2102 11 common/image.c Ramdisk data has correct checksum
2103 12 common/image.c Ramdisk verification complete, start loading
2104 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2105 13 common/image.c Start multifile image verification
2106 14 common/image.c No initial ramdisk, no multifile, continue.
2108 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2110 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2111 -31 post/post.c POST test failed, detected by post_output_backlog()
2112 -32 post/post.c POST test failed, detected by post_run_single()
2114 34 common/cmd_doc.c before loading a Image from a DOC device
2115 -35 common/cmd_doc.c Bad usage of "doc" command
2116 35 common/cmd_doc.c correct usage of "doc" command
2117 -36 common/cmd_doc.c No boot device
2118 36 common/cmd_doc.c correct boot device
2119 -37 common/cmd_doc.c Unknown Chip ID on boot device
2120 37 common/cmd_doc.c correct chip ID found, device available
2121 -38 common/cmd_doc.c Read Error on boot device
2122 38 common/cmd_doc.c reading Image header from DOC device OK
2123 -39 common/cmd_doc.c Image header has bad magic number
2124 39 common/cmd_doc.c Image header has correct magic number
2125 -40 common/cmd_doc.c Error reading Image from DOC device
2126 40 common/cmd_doc.c Image header has correct magic number
2127 41 common/cmd_ide.c before loading a Image from a IDE device
2128 -42 common/cmd_ide.c Bad usage of "ide" command
2129 42 common/cmd_ide.c correct usage of "ide" command
2130 -43 common/cmd_ide.c No boot device
2131 43 common/cmd_ide.c boot device found
2132 -44 common/cmd_ide.c Device not available
2133 44 common/cmd_ide.c Device available
2134 -45 common/cmd_ide.c wrong partition selected
2135 45 common/cmd_ide.c partition selected
2136 -46 common/cmd_ide.c Unknown partition table
2137 46 common/cmd_ide.c valid partition table found
2138 -47 common/cmd_ide.c Invalid partition type
2139 47 common/cmd_ide.c correct partition type
2140 -48 common/cmd_ide.c Error reading Image Header on boot device
2141 48 common/cmd_ide.c reading Image Header from IDE device OK
2142 -49 common/cmd_ide.c Image header has bad magic number
2143 49 common/cmd_ide.c Image header has correct magic number
2144 -50 common/cmd_ide.c Image header has bad checksum
2145 50 common/cmd_ide.c Image header has correct checksum
2146 -51 common/cmd_ide.c Error reading Image from IDE device
2147 51 common/cmd_ide.c reading Image from IDE device OK
2148 52 common/cmd_nand.c before loading a Image from a NAND device
2149 -53 common/cmd_nand.c Bad usage of "nand" command
2150 53 common/cmd_nand.c correct usage of "nand" command
2151 -54 common/cmd_nand.c No boot device
2152 54 common/cmd_nand.c boot device found
2153 -55 common/cmd_nand.c Unknown Chip ID on boot device
2154 55 common/cmd_nand.c correct chip ID found, device available
2155 -56 common/cmd_nand.c Error reading Image Header on boot device
2156 56 common/cmd_nand.c reading Image Header from NAND device OK
2157 -57 common/cmd_nand.c Image header has bad magic number
2158 57 common/cmd_nand.c Image header has correct magic number
2159 -58 common/cmd_nand.c Error reading Image from NAND device
2160 58 common/cmd_nand.c reading Image from NAND device OK
2162 -60 common/env_common.c Environment has a bad CRC, using default
2164 64 net/eth.c starting with Ethernet configuration.
2165 -64 net/eth.c no Ethernet found.
2166 65 net/eth.c Ethernet found.
2168 -80 common/cmd_net.c usage wrong
2169 80 common/cmd_net.c before calling NetLoop()
2170 -81 common/cmd_net.c some error in NetLoop() occurred
2171 81 common/cmd_net.c NetLoop() back without error
2172 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2173 82 common/cmd_net.c trying automatic boot
2174 83 common/cmd_net.c running "source" command
2175 -83 common/cmd_net.c some error in automatic boot or "source" command
2176 84 common/cmd_net.c end without errors
2181 100 common/cmd_bootm.c Kernel FIT Image has correct format
2182 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2183 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2184 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2185 102 common/cmd_bootm.c Kernel unit name specified
2186 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2187 103 common/cmd_bootm.c Found configuration node
2188 104 common/cmd_bootm.c Got kernel subimage node offset
2189 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2190 105 common/cmd_bootm.c Kernel subimage hash verification OK
2191 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2192 106 common/cmd_bootm.c Architecture check OK
2193 -106 common/cmd_bootm.c Kernel subimage has wrong type
2194 107 common/cmd_bootm.c Kernel subimage type OK
2195 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2196 108 common/cmd_bootm.c Got kernel subimage data/size
2197 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2198 -109 common/cmd_bootm.c Can't get kernel subimage type
2199 -110 common/cmd_bootm.c Can't get kernel subimage comp
2200 -111 common/cmd_bootm.c Can't get kernel subimage os
2201 -112 common/cmd_bootm.c Can't get kernel subimage load address
2202 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2204 120 common/image.c Start initial ramdisk verification
2205 -120 common/image.c Ramdisk FIT image has incorrect format
2206 121 common/image.c Ramdisk FIT image has correct format
2207 122 common/image.c No ramdisk subimage unit name, using configuration
2208 -122 common/image.c Can't get configuration for ramdisk subimage
2209 123 common/image.c Ramdisk unit name specified
2210 -124 common/image.c Can't get ramdisk subimage node offset
2211 125 common/image.c Got ramdisk subimage node offset
2212 -125 common/image.c Ramdisk subimage hash verification failed
2213 126 common/image.c Ramdisk subimage hash verification OK
2214 -126 common/image.c Ramdisk subimage for unsupported architecture
2215 127 common/image.c Architecture check OK
2216 -127 common/image.c Can't get ramdisk subimage data/size
2217 128 common/image.c Got ramdisk subimage data/size
2218 129 common/image.c Can't get ramdisk load address
2219 -129 common/image.c Got ramdisk load address
2221 -130 common/cmd_doc.c Incorrect FIT image format
2222 131 common/cmd_doc.c FIT image format OK
2224 -140 common/cmd_ide.c Incorrect FIT image format
2225 141 common/cmd_ide.c FIT image format OK
2227 -150 common/cmd_nand.c Incorrect FIT image format
2228 151 common/cmd_nand.c FIT image format OK
2230 - Automatic software updates via TFTP server
2232 CONFIG_UPDATE_TFTP_CNT_MAX
2233 CONFIG_UPDATE_TFTP_MSEC_MAX
2235 These options enable and control the auto-update feature;
2236 for a more detailed description refer to doc/README.update.
2238 - MTD Support (mtdparts command, UBI support)
2241 Adds the MTD device infrastructure from the Linux kernel.
2242 Needed for mtdparts command support.
2244 CONFIG_MTD_PARTITIONS
2246 Adds the MTD partitioning infrastructure from the Linux
2247 kernel. Needed for UBI support.
2253 [so far only for SMDK2400 boards]
2255 - Modem support enable:
2256 CONFIG_MODEM_SUPPORT
2258 - RTS/CTS Flow control enable:
2261 - Modem debug support:
2262 CONFIG_MODEM_SUPPORT_DEBUG
2264 Enables debugging stuff (char screen[1024], dbg())
2265 for modem support. Useful only with BDI2000.
2267 - Interrupt support (PPC):
2269 There are common interrupt_init() and timer_interrupt()
2270 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2271 for CPU specific initialization. interrupt_init_cpu()
2272 should set decrementer_count to appropriate value. If
2273 CPU resets decrementer automatically after interrupt
2274 (ppc4xx) it should set decrementer_count to zero.
2275 timer_interrupt() calls timer_interrupt_cpu() for CPU
2276 specific handling. If board has watchdog / status_led
2277 / other_activity_monitor it works automatically from
2278 general timer_interrupt().
2282 In the target system modem support is enabled when a
2283 specific key (key combination) is pressed during
2284 power-on. Otherwise U-Boot will boot normally
2285 (autoboot). The key_pressed() function is called from
2286 board_init(). Currently key_pressed() is a dummy
2287 function, returning 1 and thus enabling modem
2290 If there are no modem init strings in the
2291 environment, U-Boot proceed to autoboot; the
2292 previous output (banner, info printfs) will be
2295 See also: doc/README.Modem
2298 Configuration Settings:
2299 -----------------------
2301 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2302 undefine this when you're short of memory.
2304 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2305 width of the commands listed in the 'help' command output.
2307 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2308 prompt for user input.
2310 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2312 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2314 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2316 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2317 the application (usually a Linux kernel) when it is
2320 - CONFIG_SYS_BAUDRATE_TABLE:
2321 List of legal baudrate settings for this board.
2323 - CONFIG_SYS_CONSOLE_INFO_QUIET
2324 Suppress display of console information at boot.
2326 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2327 If the board specific function
2328 extern int overwrite_console (void);
2329 returns 1, the stdin, stderr and stdout are switched to the
2330 serial port, else the settings in the environment are used.
2332 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2333 Enable the call to overwrite_console().
2335 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2336 Enable overwrite of previous console environment settings.
2338 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2339 Begin and End addresses of the area used by the
2342 - CONFIG_SYS_ALT_MEMTEST:
2343 Enable an alternate, more extensive memory test.
2345 - CONFIG_SYS_MEMTEST_SCRATCH:
2346 Scratch address used by the alternate memory test
2347 You only need to set this if address zero isn't writeable
2349 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2350 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2351 this specified memory area will get subtracted from the top
2352 (end) of RAM and won't get "touched" at all by U-Boot. By
2353 fixing up gd->ram_size the Linux kernel should gets passed
2354 the now "corrected" memory size and won't touch it either.
2355 This should work for arch/ppc and arch/powerpc. Only Linux
2356 board ports in arch/powerpc with bootwrapper support that
2357 recalculate the memory size from the SDRAM controller setup
2358 will have to get fixed in Linux additionally.
2360 This option can be used as a workaround for the 440EPx/GRx
2361 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2364 WARNING: Please make sure that this value is a multiple of
2365 the Linux page size (normally 4k). If this is not the case,
2366 then the end address of the Linux memory will be located at a
2367 non page size aligned address and this could cause major
2370 - CONFIG_SYS_TFTP_LOADADDR:
2371 Default load address for network file downloads
2373 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2374 Enable temporary baudrate change while serial download
2376 - CONFIG_SYS_SDRAM_BASE:
2377 Physical start address of SDRAM. _Must_ be 0 here.
2379 - CONFIG_SYS_MBIO_BASE:
2380 Physical start address of Motherboard I/O (if using a
2383 - CONFIG_SYS_FLASH_BASE:
2384 Physical start address of Flash memory.
2386 - CONFIG_SYS_MONITOR_BASE:
2387 Physical start address of boot monitor code (set by
2388 make config files to be same as the text base address
2389 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2390 CONFIG_SYS_FLASH_BASE when booting from flash.
2392 - CONFIG_SYS_MONITOR_LEN:
2393 Size of memory reserved for monitor code, used to
2394 determine _at_compile_time_ (!) if the environment is
2395 embedded within the U-Boot image, or in a separate
2398 - CONFIG_SYS_MALLOC_LEN:
2399 Size of DRAM reserved for malloc() use.
2401 - CONFIG_SYS_BOOTM_LEN:
2402 Normally compressed uImages are limited to an
2403 uncompressed size of 8 MBytes. If this is not enough,
2404 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2405 to adjust this setting to your needs.
2407 - CONFIG_SYS_BOOTMAPSZ:
2408 Maximum size of memory mapped by the startup code of
2409 the Linux kernel; all data that must be processed by
2410 the Linux kernel (bd_info, boot arguments, FDT blob if
2411 used) must be put below this limit, unless "bootm_low"
2412 enviroment variable is defined and non-zero. In such case
2413 all data for the Linux kernel must be between "bootm_low"
2414 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2415 variable "bootm_mapsize" will override the value of
2416 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2417 then the value in "bootm_size" will be used instead.
2419 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2420 Enable initrd_high functionality. If defined then the
2421 initrd_high feature is enabled and the bootm ramdisk subcommand
2424 - CONFIG_SYS_BOOT_GET_CMDLINE:
2425 Enables allocating and saving kernel cmdline in space between
2426 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2428 - CONFIG_SYS_BOOT_GET_KBD:
2429 Enables allocating and saving a kernel copy of the bd_info in
2430 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2432 - CONFIG_SYS_MAX_FLASH_BANKS:
2433 Max number of Flash memory banks
2435 - CONFIG_SYS_MAX_FLASH_SECT:
2436 Max number of sectors on a Flash chip
2438 - CONFIG_SYS_FLASH_ERASE_TOUT:
2439 Timeout for Flash erase operations (in ms)
2441 - CONFIG_SYS_FLASH_WRITE_TOUT:
2442 Timeout for Flash write operations (in ms)
2444 - CONFIG_SYS_FLASH_LOCK_TOUT
2445 Timeout for Flash set sector lock bit operation (in ms)
2447 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2448 Timeout for Flash clear lock bits operation (in ms)
2450 - CONFIG_SYS_FLASH_PROTECTION
2451 If defined, hardware flash sectors protection is used
2452 instead of U-Boot software protection.
2454 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2456 Enable TFTP transfers directly to flash memory;
2457 without this option such a download has to be
2458 performed in two steps: (1) download to RAM, and (2)
2459 copy from RAM to flash.
2461 The two-step approach is usually more reliable, since
2462 you can check if the download worked before you erase
2463 the flash, but in some situations (when system RAM is
2464 too limited to allow for a temporary copy of the
2465 downloaded image) this option may be very useful.
2467 - CONFIG_SYS_FLASH_CFI:
2468 Define if the flash driver uses extra elements in the
2469 common flash structure for storing flash geometry.
2471 - CONFIG_FLASH_CFI_DRIVER
2472 This option also enables the building of the cfi_flash driver
2473 in the drivers directory
2475 - CONFIG_FLASH_CFI_MTD
2476 This option enables the building of the cfi_mtd driver
2477 in the drivers directory. The driver exports CFI flash
2480 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2481 Use buffered writes to flash.
2483 - CONFIG_FLASH_SPANSION_S29WS_N
2484 s29ws-n MirrorBit flash has non-standard addresses for buffered
2487 - CONFIG_SYS_FLASH_QUIET_TEST
2488 If this option is defined, the common CFI flash doesn't
2489 print it's warning upon not recognized FLASH banks. This
2490 is useful, if some of the configured banks are only
2491 optionally available.
2493 - CONFIG_FLASH_SHOW_PROGRESS
2494 If defined (must be an integer), print out countdown
2495 digits and dots. Recommended value: 45 (9..1) for 80
2496 column displays, 15 (3..1) for 40 column displays.
2498 - CONFIG_SYS_RX_ETH_BUFFER:
2499 Defines the number of Ethernet receive buffers. On some
2500 Ethernet controllers it is recommended to set this value
2501 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2502 buffers can be full shortly after enabling the interface
2503 on high Ethernet traffic.
2504 Defaults to 4 if not defined.
2506 - CONFIG_ENV_MAX_ENTRIES
2508 Maximum number of entries in the hash table that is used
2509 internally to store the environment settings. The default
2510 setting is supposed to be generous and should work in most
2511 cases. This setting can be used to tune behaviour; see
2512 lib/hashtable.c for details.
2514 The following definitions that deal with the placement and management
2515 of environment data (variable area); in general, we support the
2516 following configurations:
2518 - CONFIG_ENV_IS_IN_FLASH:
2520 Define this if the environment is in flash memory.
2522 a) The environment occupies one whole flash sector, which is
2523 "embedded" in the text segment with the U-Boot code. This
2524 happens usually with "bottom boot sector" or "top boot
2525 sector" type flash chips, which have several smaller
2526 sectors at the start or the end. For instance, such a
2527 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2528 such a case you would place the environment in one of the
2529 4 kB sectors - with U-Boot code before and after it. With
2530 "top boot sector" type flash chips, you would put the
2531 environment in one of the last sectors, leaving a gap
2532 between U-Boot and the environment.
2534 - CONFIG_ENV_OFFSET:
2536 Offset of environment data (variable area) to the
2537 beginning of flash memory; for instance, with bottom boot
2538 type flash chips the second sector can be used: the offset
2539 for this sector is given here.
2541 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2545 This is just another way to specify the start address of
2546 the flash sector containing the environment (instead of
2549 - CONFIG_ENV_SECT_SIZE:
2551 Size of the sector containing the environment.
2554 b) Sometimes flash chips have few, equal sized, BIG sectors.
2555 In such a case you don't want to spend a whole sector for
2560 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2561 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2562 of this flash sector for the environment. This saves
2563 memory for the RAM copy of the environment.
2565 It may also save flash memory if you decide to use this
2566 when your environment is "embedded" within U-Boot code,
2567 since then the remainder of the flash sector could be used
2568 for U-Boot code. It should be pointed out that this is
2569 STRONGLY DISCOURAGED from a robustness point of view:
2570 updating the environment in flash makes it always
2571 necessary to erase the WHOLE sector. If something goes
2572 wrong before the contents has been restored from a copy in
2573 RAM, your target system will be dead.
2575 - CONFIG_ENV_ADDR_REDUND
2576 CONFIG_ENV_SIZE_REDUND
2578 These settings describe a second storage area used to hold
2579 a redundant copy of the environment data, so that there is
2580 a valid backup copy in case there is a power failure during
2581 a "saveenv" operation.
2583 BE CAREFUL! Any changes to the flash layout, and some changes to the
2584 source code will make it necessary to adapt <board>/u-boot.lds*
2588 - CONFIG_ENV_IS_IN_NVRAM:
2590 Define this if you have some non-volatile memory device
2591 (NVRAM, battery buffered SRAM) which you want to use for the
2597 These two #defines are used to determine the memory area you
2598 want to use for environment. It is assumed that this memory
2599 can just be read and written to, without any special
2602 BE CAREFUL! The first access to the environment happens quite early
2603 in U-Boot initalization (when we try to get the setting of for the
2604 console baudrate). You *MUST* have mapped your NVRAM area then, or
2607 Please note that even with NVRAM we still use a copy of the
2608 environment in RAM: we could work on NVRAM directly, but we want to
2609 keep settings there always unmodified except somebody uses "saveenv"
2610 to save the current settings.
2613 - CONFIG_ENV_IS_IN_EEPROM:
2615 Use this if you have an EEPROM or similar serial access
2616 device and a driver for it.
2618 - CONFIG_ENV_OFFSET:
2621 These two #defines specify the offset and size of the
2622 environment area within the total memory of your EEPROM.
2624 - CONFIG_SYS_I2C_EEPROM_ADDR:
2625 If defined, specified the chip address of the EEPROM device.
2626 The default address is zero.
2628 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2629 If defined, the number of bits used to address bytes in a
2630 single page in the EEPROM device. A 64 byte page, for example
2631 would require six bits.
2633 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2634 If defined, the number of milliseconds to delay between
2635 page writes. The default is zero milliseconds.
2637 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2638 The length in bytes of the EEPROM memory array address. Note
2639 that this is NOT the chip address length!
2641 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2642 EEPROM chips that implement "address overflow" are ones
2643 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2644 address and the extra bits end up in the "chip address" bit
2645 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2648 Note that we consider the length of the address field to
2649 still be one byte because the extra address bits are hidden
2650 in the chip address.
2652 - CONFIG_SYS_EEPROM_SIZE:
2653 The size in bytes of the EEPROM device.
2655 - CONFIG_ENV_EEPROM_IS_ON_I2C
2656 define this, if you have I2C and SPI activated, and your
2657 EEPROM, which holds the environment, is on the I2C bus.
2659 - CONFIG_I2C_ENV_EEPROM_BUS
2660 if you have an Environment on an EEPROM reached over
2661 I2C muxes, you can define here, how to reach this
2662 EEPROM. For example:
2664 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2666 EEPROM which holds the environment, is reached over
2667 a pca9547 i2c mux with address 0x70, channel 3.
2669 - CONFIG_ENV_IS_IN_DATAFLASH:
2671 Define this if you have a DataFlash memory device which you
2672 want to use for the environment.
2674 - CONFIG_ENV_OFFSET:
2678 These three #defines specify the offset and size of the
2679 environment area within the total memory of your DataFlash placed
2680 at the specified address.
2682 - CONFIG_ENV_IS_IN_NAND:
2684 Define this if you have a NAND device which you want to use
2685 for the environment.
2687 - CONFIG_ENV_OFFSET:
2690 These two #defines specify the offset and size of the environment
2691 area within the first NAND device. CONFIG_ENV_OFFSET must be
2692 aligned to an erase block boundary.
2694 - CONFIG_ENV_OFFSET_REDUND (optional):
2696 This setting describes a second storage area of CONFIG_ENV_SIZE
2697 size used to hold a redundant copy of the environment data, so
2698 that there is a valid backup copy in case there is a power failure
2699 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2700 aligned to an erase block boundary.
2702 - CONFIG_ENV_RANGE (optional):
2704 Specifies the length of the region in which the environment
2705 can be written. This should be a multiple of the NAND device's
2706 block size. Specifying a range with more erase blocks than
2707 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2708 the range to be avoided.
2710 - CONFIG_ENV_OFFSET_OOB (optional):
2712 Enables support for dynamically retrieving the offset of the
2713 environment from block zero's out-of-band data. The
2714 "nand env.oob" command can be used to record this offset.
2715 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2716 using CONFIG_ENV_OFFSET_OOB.
2718 - CONFIG_NAND_ENV_DST
2720 Defines address in RAM to which the nand_spl code should copy the
2721 environment. If redundant environment is used, it will be copied to
2722 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2724 - CONFIG_SYS_SPI_INIT_OFFSET
2726 Defines offset to the initial SPI buffer area in DPRAM. The
2727 area is used at an early stage (ROM part) if the environment
2728 is configured to reside in the SPI EEPROM: We need a 520 byte
2729 scratch DPRAM area. It is used between the two initialization
2730 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2731 to be a good choice since it makes it far enough from the
2732 start of the data area as well as from the stack pointer.
2734 Please note that the environment is read-only until the monitor
2735 has been relocated to RAM and a RAM copy of the environment has been
2736 created; also, when using EEPROM you will have to use getenv_f()
2737 until then to read environment variables.
2739 The environment is protected by a CRC32 checksum. Before the monitor
2740 is relocated into RAM, as a result of a bad CRC you will be working
2741 with the compiled-in default environment - *silently*!!! [This is
2742 necessary, because the first environment variable we need is the
2743 "baudrate" setting for the console - if we have a bad CRC, we don't
2744 have any device yet where we could complain.]
2746 Note: once the monitor has been relocated, then it will complain if
2747 the default environment is used; a new CRC is computed as soon as you
2748 use the "saveenv" command to store a valid environment.
2750 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2751 Echo the inverted Ethernet link state to the fault LED.
2753 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2754 also needs to be defined.
2756 - CONFIG_SYS_FAULT_MII_ADDR:
2757 MII address of the PHY to check for the Ethernet link state.
2759 - CONFIG_NS16550_MIN_FUNCTIONS:
2760 Define this if you desire to only have use of the NS16550_init
2761 and NS16550_putc functions for the serial driver located at
2762 drivers/serial/ns16550.c. This option is useful for saving
2763 space for already greatly restricted images, including but not
2764 limited to NAND_SPL configurations.
2766 Low Level (hardware related) configuration options:
2767 ---------------------------------------------------
2769 - CONFIG_SYS_CACHELINE_SIZE:
2770 Cache Line Size of the CPU.
2772 - CONFIG_SYS_DEFAULT_IMMR:
2773 Default address of the IMMR after system reset.
2775 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2776 and RPXsuper) to be able to adjust the position of
2777 the IMMR register after a reset.
2779 - Floppy Disk Support:
2780 CONFIG_SYS_FDC_DRIVE_NUMBER
2782 the default drive number (default value 0)
2784 CONFIG_SYS_ISA_IO_STRIDE
2786 defines the spacing between FDC chipset registers
2789 CONFIG_SYS_ISA_IO_OFFSET
2791 defines the offset of register from address. It
2792 depends on which part of the data bus is connected to
2793 the FDC chipset. (default value 0)
2795 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2796 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2799 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2800 fdc_hw_init() is called at the beginning of the FDC
2801 setup. fdc_hw_init() must be provided by the board
2802 source code. It is used to make hardware dependant
2806 Most IDE controllers were designed to be connected with PCI
2807 interface. Only few of them were designed for AHB interface.
2808 When software is doing ATA command and data transfer to
2809 IDE devices through IDE-AHB controller, some additional
2810 registers accessing to these kind of IDE-AHB controller
2813 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2814 DO NOT CHANGE unless you know exactly what you're
2815 doing! (11-4) [MPC8xx/82xx systems only]
2817 - CONFIG_SYS_INIT_RAM_ADDR:
2819 Start address of memory area that can be used for
2820 initial data and stack; please note that this must be
2821 writable memory that is working WITHOUT special
2822 initialization, i. e. you CANNOT use normal RAM which
2823 will become available only after programming the
2824 memory controller and running certain initialization
2827 U-Boot uses the following memory types:
2828 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2829 - MPC824X: data cache
2830 - PPC4xx: data cache
2832 - CONFIG_SYS_GBL_DATA_OFFSET:
2834 Offset of the initial data structure in the memory
2835 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2836 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2837 data is located at the end of the available space
2838 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2839 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2840 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2841 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2844 On the MPC824X (or other systems that use the data
2845 cache for initial memory) the address chosen for
2846 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2847 point to an otherwise UNUSED address space between
2848 the top of RAM and the start of the PCI space.
2850 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2852 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2854 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2856 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2858 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2860 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2862 - CONFIG_SYS_OR_TIMING_SDRAM:
2865 - CONFIG_SYS_MAMR_PTA:
2866 periodic timer for refresh
2868 - CONFIG_SYS_DER: Debug Event Register (37-47)
2870 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2871 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2872 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2873 CONFIG_SYS_BR1_PRELIM:
2874 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2876 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2877 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2878 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2879 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2881 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2882 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2883 Machine Mode Register and Memory Periodic Timer
2884 Prescaler definitions (SDRAM timing)
2886 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2887 enable I2C microcode relocation patch (MPC8xx);
2888 define relocation offset in DPRAM [DSP2]
2890 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2891 enable SMC microcode relocation patch (MPC8xx);
2892 define relocation offset in DPRAM [SMC1]
2894 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2895 enable SPI microcode relocation patch (MPC8xx);
2896 define relocation offset in DPRAM [SCC4]
2898 - CONFIG_SYS_USE_OSCCLK:
2899 Use OSCM clock mode on MBX8xx board. Be careful,
2900 wrong setting might damage your board. Read
2901 doc/README.MBX before setting this variable!
2903 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2904 Offset of the bootmode word in DPRAM used by post
2905 (Power On Self Tests). This definition overrides
2906 #define'd default value in commproc.h resp.
2909 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2910 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2911 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2912 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2913 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2914 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2915 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2916 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2917 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2919 - CONFIG_PCI_DISABLE_PCIE:
2920 Disable PCI-Express on systems where it is supported but not
2924 Chip has SRIO or not
2927 Board has SRIO 1 port available
2930 Board has SRIO 2 port available
2932 - CONFIG_SYS_SRIOn_MEM_VIRT:
2933 Virtual Address of SRIO port 'n' memory region
2935 - CONFIG_SYS_SRIOn_MEM_PHYS:
2936 Physical Address of SRIO port 'n' memory region
2938 - CONFIG_SYS_SRIOn_MEM_SIZE:
2939 Size of SRIO port 'n' memory region
2941 - CONFIG_SYS_NDFC_16
2942 Defined to tell the NDFC that the NAND chip is using a
2945 - CONFIG_SYS_NDFC_EBC0_CFG
2946 Sets the EBC0_CFG register for the NDFC. If not defined
2947 a default value will be used.
2950 Get DDR timing information from an I2C EEPROM. Common
2951 with pluggable memory modules such as SODIMMs
2954 I2C address of the SPD EEPROM
2956 - CONFIG_SYS_SPD_BUS_NUM
2957 If SPD EEPROM is on an I2C bus other than the first
2958 one, specify here. Note that the value must resolve
2959 to something your driver can deal with.
2961 - CONFIG_SYS_DDR_RAW_TIMING
2962 Get DDR timing information from other than SPD. Common with
2963 soldered DDR chips onboard without SPD. DDR raw timing
2964 parameters are extracted from datasheet and hard-coded into
2965 header files or board specific files.
2967 - CONFIG_SYS_83XX_DDR_USES_CS0
2968 Only for 83xx systems. If specified, then DDR should
2969 be configured using CS0 and CS1 instead of CS2 and CS3.
2971 - CONFIG_ETHER_ON_FEC[12]
2972 Define to enable FEC[12] on a 8xx series processor.
2974 - CONFIG_FEC[12]_PHY
2975 Define to the hardcoded PHY address which corresponds
2976 to the given FEC; i. e.
2977 #define CONFIG_FEC1_PHY 4
2978 means that the PHY with address 4 is connected to FEC1
2980 When set to -1, means to probe for first available.
2982 - CONFIG_FEC[12]_PHY_NORXERR
2983 The PHY does not have a RXERR line (RMII only).
2984 (so program the FEC to ignore it).
2987 Enable RMII mode for all FECs.
2988 Note that this is a global option, we can't
2989 have one FEC in standard MII mode and another in RMII mode.
2991 - CONFIG_CRC32_VERIFY
2992 Add a verify option to the crc32 command.
2995 => crc32 -v <address> <count> <crc32>
2997 Where address/count indicate a memory area
2998 and crc32 is the correct crc32 which the
3002 Add the "loopw" memory command. This only takes effect if
3003 the memory commands are activated globally (CONFIG_CMD_MEM).
3006 Add the "mdc" and "mwc" memory commands. These are cyclic
3011 This command will print 4 bytes (10,11,12,13) each 500 ms.
3013 => mwc.l 100 12345678 10
3014 This command will write 12345678 to address 100 all 10 ms.
3016 This only takes effect if the memory commands are activated
3017 globally (CONFIG_CMD_MEM).
3019 - CONFIG_SKIP_LOWLEVEL_INIT
3020 [ARM only] If this variable is defined, then certain
3021 low level initializations (like setting up the memory
3022 controller) are omitted and/or U-Boot does not
3023 relocate itself into RAM.
3025 Normally this variable MUST NOT be defined. The only
3026 exception is when U-Boot is loaded (to RAM) by some
3027 other boot loader or by a debugger which performs
3028 these initializations itself.
3031 Modifies the behaviour of start.S when compiling a loader
3032 that is executed before the actual U-Boot. E.g. when
3033 compiling a NAND SPL.
3035 - CONFIG_USE_ARCH_MEMCPY
3036 CONFIG_USE_ARCH_MEMSET
3037 If these options are used a optimized version of memcpy/memset will
3038 be used if available. These functions may be faster under some
3039 conditions but may increase the binary size.
3041 Building the Software:
3042 ======================
3044 Building U-Boot has been tested in several native build environments
3045 and in many different cross environments. Of course we cannot support
3046 all possibly existing versions of cross development tools in all
3047 (potentially obsolete) versions. In case of tool chain problems we
3048 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3049 which is extensively used to build and test U-Boot.
3051 If you are not using a native environment, it is assumed that you
3052 have GNU cross compiling tools available in your path. In this case,
3053 you must set the environment variable CROSS_COMPILE in your shell.
3054 Note that no changes to the Makefile or any other source files are
3055 necessary. For example using the ELDK on a 4xx CPU, please enter:
3057 $ CROSS_COMPILE=ppc_4xx-
3058 $ export CROSS_COMPILE
3060 Note: If you wish to generate Windows versions of the utilities in
3061 the tools directory you can use the MinGW toolchain
3062 (http://www.mingw.org). Set your HOST tools to the MinGW
3063 toolchain and execute 'make tools'. For example:
3065 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3067 Binaries such as tools/mkimage.exe will be created which can
3068 be executed on computers running Windows.
3070 U-Boot is intended to be simple to build. After installing the
3071 sources you must configure U-Boot for one specific board type. This
3076 where "NAME_config" is the name of one of the existing configu-
3077 rations; see the main Makefile for supported names.
3079 Note: for some board special configuration names may exist; check if
3080 additional information is available from the board vendor; for
3081 instance, the TQM823L systems are available without (standard)
3082 or with LCD support. You can select such additional "features"
3083 when choosing the configuration, i. e.
3086 - will configure for a plain TQM823L, i. e. no LCD support
3088 make TQM823L_LCD_config
3089 - will configure for a TQM823L with U-Boot console on LCD
3094 Finally, type "make all", and you should get some working U-Boot
3095 images ready for download to / installation on your system:
3097 - "u-boot.bin" is a raw binary image
3098 - "u-boot" is an image in ELF binary format
3099 - "u-boot.srec" is in Motorola S-Record format
3101 By default the build is performed locally and the objects are saved
3102 in the source directory. One of the two methods can be used to change
3103 this behavior and build U-Boot to some external directory:
3105 1. Add O= to the make command line invocations:
3107 make O=/tmp/build distclean
3108 make O=/tmp/build NAME_config
3109 make O=/tmp/build all
3111 2. Set environment variable BUILD_DIR to point to the desired location:
3113 export BUILD_DIR=/tmp/build
3118 Note that the command line "O=" setting overrides the BUILD_DIR environment
3122 Please be aware that the Makefiles assume you are using GNU make, so
3123 for instance on NetBSD you might need to use "gmake" instead of
3127 If the system board that you have is not listed, then you will need
3128 to port U-Boot to your hardware platform. To do this, follow these
3131 1. Add a new configuration option for your board to the toplevel
3132 "Makefile" and to the "MAKEALL" script, using the existing
3133 entries as examples. Note that here and at many other places
3134 boards and other names are listed in alphabetical sort order. Please
3136 2. Create a new directory to hold your board specific code. Add any
3137 files you need. In your board directory, you will need at least
3138 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3139 3. Create a new configuration file "include/configs/<board>.h" for
3141 3. If you're porting U-Boot to a new CPU, then also create a new
3142 directory to hold your CPU specific code. Add any files you need.
3143 4. Run "make <board>_config" with your new name.
3144 5. Type "make", and you should get a working "u-boot.srec" file
3145 to be installed on your target system.
3146 6. Debug and solve any problems that might arise.
3147 [Of course, this last step is much harder than it sounds.]
3150 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3151 ==============================================================
3153 If you have modified U-Boot sources (for instance added a new board
3154 or support for new devices, a new CPU, etc.) you are expected to
3155 provide feedback to the other developers. The feedback normally takes
3156 the form of a "patch", i. e. a context diff against a certain (latest
3157 official or latest in the git repository) version of U-Boot sources.
3159 But before you submit such a patch, please verify that your modifi-
3160 cation did not break existing code. At least make sure that *ALL* of
3161 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3162 just run the "MAKEALL" script, which will configure and build U-Boot
3163 for ALL supported system. Be warned, this will take a while. You can
3164 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3165 environment variable to the script, i. e. to use the ELDK cross tools
3168 CROSS_COMPILE=ppc_8xx- MAKEALL
3170 or to build on a native PowerPC system you can type
3172 CROSS_COMPILE=' ' MAKEALL
3174 When using the MAKEALL script, the default behaviour is to build
3175 U-Boot in the source directory. This location can be changed by
3176 setting the BUILD_DIR environment variable. Also, for each target
3177 built, the MAKEALL script saves two log files (<target>.ERR and
3178 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3179 location can be changed by setting the MAKEALL_LOGDIR environment
3180 variable. For example:
3182 export BUILD_DIR=/tmp/build
3183 export MAKEALL_LOGDIR=/tmp/log
3184 CROSS_COMPILE=ppc_8xx- MAKEALL
3186 With the above settings build objects are saved in the /tmp/build,
3187 log files are saved in the /tmp/log and the source tree remains clean
3188 during the whole build process.
3191 See also "U-Boot Porting Guide" below.
3194 Monitor Commands - Overview:
3195 ============================
3197 go - start application at address 'addr'
3198 run - run commands in an environment variable
3199 bootm - boot application image from memory
3200 bootp - boot image via network using BootP/TFTP protocol
3201 tftpboot- boot image via network using TFTP protocol
3202 and env variables "ipaddr" and "serverip"
3203 (and eventually "gatewayip")
3204 rarpboot- boot image via network using RARP/TFTP protocol
3205 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3206 loads - load S-Record file over serial line
3207 loadb - load binary file over serial line (kermit mode)
3209 mm - memory modify (auto-incrementing)
3210 nm - memory modify (constant address)
3211 mw - memory write (fill)
3213 cmp - memory compare
3214 crc32 - checksum calculation
3215 i2c - I2C sub-system
3216 sspi - SPI utility commands
3217 base - print or set address offset
3218 printenv- print environment variables
3219 setenv - set environment variables
3220 saveenv - save environment variables to persistent storage
3221 protect - enable or disable FLASH write protection
3222 erase - erase FLASH memory
3223 flinfo - print FLASH memory information
3224 bdinfo - print Board Info structure
3225 iminfo - print header information for application image
3226 coninfo - print console devices and informations
3227 ide - IDE sub-system
3228 loop - infinite loop on address range
3229 loopw - infinite write loop on address range
3230 mtest - simple RAM test
3231 icache - enable or disable instruction cache
3232 dcache - enable or disable data cache
3233 reset - Perform RESET of the CPU
3234 echo - echo args to console
3235 version - print monitor version
3236 help - print online help
3237 ? - alias for 'help'
3240 Monitor Commands - Detailed Description:
3241 ========================================
3245 For now: just type "help <command>".
3248 Environment Variables:
3249 ======================
3251 U-Boot supports user configuration using Environment Variables which
3252 can be made persistent by saving to Flash memory.
3254 Environment Variables are set using "setenv", printed using
3255 "printenv", and saved to Flash using "saveenv". Using "setenv"
3256 without a value can be used to delete a variable from the
3257 environment. As long as you don't save the environment you are
3258 working with an in-memory copy. In case the Flash area containing the
3259 environment is erased by accident, a default environment is provided.
3261 Some configuration options can be set using Environment Variables.
3263 List of environment variables (most likely not complete):
3265 baudrate - see CONFIG_BAUDRATE
3267 bootdelay - see CONFIG_BOOTDELAY
3269 bootcmd - see CONFIG_BOOTCOMMAND
3271 bootargs - Boot arguments when booting an RTOS image
3273 bootfile - Name of the image to load with TFTP
3275 bootm_low - Memory range available for image processing in the bootm
3276 command can be restricted. This variable is given as
3277 a hexadecimal number and defines lowest address allowed
3278 for use by the bootm command. See also "bootm_size"
3279 environment variable. Address defined by "bootm_low" is
3280 also the base of the initial memory mapping for the Linux
3281 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3284 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3285 This variable is given as a hexadecimal number and it
3286 defines the size of the memory region starting at base
3287 address bootm_low that is accessible by the Linux kernel
3288 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3289 as the default value if it is defined, and bootm_size is
3292 bootm_size - Memory range available for image processing in the bootm
3293 command can be restricted. This variable is given as
3294 a hexadecimal number and defines the size of the region
3295 allowed for use by the bootm command. See also "bootm_low"
3296 environment variable.
3298 updatefile - Location of the software update file on a TFTP server, used
3299 by the automatic software update feature. Please refer to
3300 documentation in doc/README.update for more details.
3302 autoload - if set to "no" (any string beginning with 'n'),
3303 "bootp" will just load perform a lookup of the
3304 configuration from the BOOTP server, but not try to
3305 load any image using TFTP
3307 autostart - if set to "yes", an image loaded using the "bootp",
3308 "rarpboot", "tftpboot" or "diskboot" commands will
3309 be automatically started (by internally calling
3312 If set to "no", a standalone image passed to the
3313 "bootm" command will be copied to the load address
3314 (and eventually uncompressed), but NOT be started.
3315 This can be used to load and uncompress arbitrary
3318 fdt_high - if set this restricts the maximum address that the
3319 flattened device tree will be copied into upon boot.
3320 If this is set to the special value 0xFFFFFFFF then
3321 the fdt will not be copied at all on boot. For this
3322 to work it must reside in writable memory, have
3323 sufficient padding on the end of it for u-boot to
3324 add the information it needs into it, and the memory
3325 must be accessible by the kernel.
3327 i2cfast - (PPC405GP|PPC405EP only)
3328 if set to 'y' configures Linux I2C driver for fast
3329 mode (400kHZ). This environment variable is used in
3330 initialization code. So, for changes to be effective
3331 it must be saved and board must be reset.
3333 initrd_high - restrict positioning of initrd images:
3334 If this variable is not set, initrd images will be
3335 copied to the highest possible address in RAM; this
3336 is usually what you want since it allows for
3337 maximum initrd size. If for some reason you want to
3338 make sure that the initrd image is loaded below the
3339 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3340 variable to a value of "no" or "off" or "0".
3341 Alternatively, you can set it to a maximum upper
3342 address to use (U-Boot will still check that it
3343 does not overwrite the U-Boot stack and data).
3345 For instance, when you have a system with 16 MB
3346 RAM, and want to reserve 4 MB from use by Linux,
3347 you can do this by adding "mem=12M" to the value of
3348 the "bootargs" variable. However, now you must make
3349 sure that the initrd image is placed in the first
3350 12 MB as well - this can be done with
3352 setenv initrd_high 00c00000
3354 If you set initrd_high to 0xFFFFFFFF, this is an
3355 indication to U-Boot that all addresses are legal
3356 for the Linux kernel, including addresses in flash
3357 memory. In this case U-Boot will NOT COPY the
3358 ramdisk at all. This may be useful to reduce the
3359 boot time on your system, but requires that this
3360 feature is supported by your Linux kernel.
3362 ipaddr - IP address; needed for tftpboot command
3364 loadaddr - Default load address for commands like "bootp",
3365 "rarpboot", "tftpboot", "loadb" or "diskboot"
3367 loads_echo - see CONFIG_LOADS_ECHO
3369 serverip - TFTP server IP address; needed for tftpboot command
3371 bootretry - see CONFIG_BOOT_RETRY_TIME
3373 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3375 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3377 ethprime - When CONFIG_NET_MULTI is enabled controls which
3378 interface is used first.
3380 ethact - When CONFIG_NET_MULTI is enabled controls which
3381 interface is currently active. For example you
3382 can do the following
3384 => setenv ethact FEC
3385 => ping 192.168.0.1 # traffic sent on FEC
3386 => setenv ethact SCC
3387 => ping 10.0.0.1 # traffic sent on SCC
3389 ethrotate - When set to "no" U-Boot does not go through all
3390 available network interfaces.
3391 It just stays at the currently selected interface.
3393 netretry - When set to "no" each network operation will
3394 either succeed or fail without retrying.
3395 When set to "once" the network operation will
3396 fail when all the available network interfaces
3397 are tried once without success.
3398 Useful on scripts which control the retry operation
3401 npe_ucode - set load address for the NPE microcode
3403 tftpsrcport - If this is set, the value is used for TFTP's
3406 tftpdstport - If this is set, the value is used for TFTP's UDP
3407 destination port instead of the Well Know Port 69.
3409 tftpblocksize - Block size to use for TFTP transfers; if not set,
3410 we use the TFTP server's default block size
3412 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3413 seconds, minimum value is 1000 = 1 second). Defines
3414 when a packet is considered to be lost so it has to
3415 be retransmitted. The default is 5000 = 5 seconds.
3416 Lowering this value may make downloads succeed
3417 faster in networks with high packet loss rates or
3418 with unreliable TFTP servers.
3420 vlan - When set to a value < 4095 the traffic over
3421 Ethernet is encapsulated/received over 802.1q
3424 The following environment variables may be used and automatically
3425 updated by the network boot commands ("bootp" and "rarpboot"),
3426 depending the information provided by your boot server:
3428 bootfile - see above
3429 dnsip - IP address of your Domain Name Server
3430 dnsip2 - IP address of your secondary Domain Name Server
3431 gatewayip - IP address of the Gateway (Router) to use
3432 hostname - Target hostname
3434 netmask - Subnet Mask
3435 rootpath - Pathname of the root filesystem on the NFS server
3436 serverip - see above
3439 There are two special Environment Variables:
3441 serial# - contains hardware identification information such
3442 as type string and/or serial number
3443 ethaddr - Ethernet address
3445 These variables can be set only once (usually during manufacturing of
3446 the board). U-Boot refuses to delete or overwrite these variables
3447 once they have been set once.
3450 Further special Environment Variables:
3452 ver - Contains the U-Boot version string as printed
3453 with the "version" command. This variable is
3454 readonly (see CONFIG_VERSION_VARIABLE).
3457 Please note that changes to some configuration parameters may take
3458 only effect after the next boot (yes, that's just like Windoze :-).
3461 Command Line Parsing:
3462 =====================
3464 There are two different command line parsers available with U-Boot:
3465 the old "simple" one, and the much more powerful "hush" shell:
3467 Old, simple command line parser:
3468 --------------------------------
3470 - supports environment variables (through setenv / saveenv commands)
3471 - several commands on one line, separated by ';'
3472 - variable substitution using "... ${name} ..." syntax
3473 - special characters ('$', ';') can be escaped by prefixing with '\',
3475 setenv bootcmd bootm \${address}
3476 - You can also escape text by enclosing in single apostrophes, for example:
3477 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3482 - similar to Bourne shell, with control structures like
3483 if...then...else...fi, for...do...done; while...do...done,
3484 until...do...done, ...
3485 - supports environment ("global") variables (through setenv / saveenv
3486 commands) and local shell variables (through standard shell syntax
3487 "name=value"); only environment variables can be used with "run"
3493 (1) If a command line (or an environment variable executed by a "run"
3494 command) contains several commands separated by semicolon, and
3495 one of these commands fails, then the remaining commands will be
3498 (2) If you execute several variables with one call to run (i. e.
3499 calling run with a list of variables as arguments), any failing
3500 command will cause "run" to terminate, i. e. the remaining
3501 variables are not executed.
3503 Note for Redundant Ethernet Interfaces:
3504 =======================================
3506 Some boards come with redundant Ethernet interfaces; U-Boot supports
3507 such configurations and is capable of automatic selection of a
3508 "working" interface when needed. MAC assignment works as follows:
3510 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3511 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3512 "eth1addr" (=>eth1), "eth2addr", ...
3514 If the network interface stores some valid MAC address (for instance
3515 in SROM), this is used as default address if there is NO correspon-
3516 ding setting in the environment; if the corresponding environment
3517 variable is set, this overrides the settings in the card; that means:
3519 o If the SROM has a valid MAC address, and there is no address in the
3520 environment, the SROM's address is used.
3522 o If there is no valid address in the SROM, and a definition in the
3523 environment exists, then the value from the environment variable is
3526 o If both the SROM and the environment contain a MAC address, and
3527 both addresses are the same, this MAC address is used.
3529 o If both the SROM and the environment contain a MAC address, and the
3530 addresses differ, the value from the environment is used and a
3533 o If neither SROM nor the environment contain a MAC address, an error
3536 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3537 will be programmed into hardware as part of the initialization process. This
3538 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3539 The naming convention is as follows:
3540 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3545 U-Boot is capable of booting (and performing other auxiliary operations on)
3546 images in two formats:
3548 New uImage format (FIT)
3549 -----------------------
3551 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3552 to Flattened Device Tree). It allows the use of images with multiple
3553 components (several kernels, ramdisks, etc.), with contents protected by
3554 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3560 Old image format is based on binary files which can be basically anything,
3561 preceded by a special header; see the definitions in include/image.h for
3562 details; basically, the header defines the following image properties:
3564 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3565 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3566 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3567 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3569 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3570 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3571 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3572 * Compression Type (uncompressed, gzip, bzip2)
3578 The header is marked by a special Magic Number, and both the header
3579 and the data portions of the image are secured against corruption by
3586 Although U-Boot should support any OS or standalone application
3587 easily, the main focus has always been on Linux during the design of
3590 U-Boot includes many features that so far have been part of some
3591 special "boot loader" code within the Linux kernel. Also, any
3592 "initrd" images to be used are no longer part of one big Linux image;
3593 instead, kernel and "initrd" are separate images. This implementation
3594 serves several purposes:
3596 - the same features can be used for other OS or standalone
3597 applications (for instance: using compressed images to reduce the
3598 Flash memory footprint)
3600 - it becomes much easier to port new Linux kernel versions because
3601 lots of low-level, hardware dependent stuff are done by U-Boot
3603 - the same Linux kernel image can now be used with different "initrd"
3604 images; of course this also means that different kernel images can
3605 be run with the same "initrd". This makes testing easier (you don't
3606 have to build a new "zImage.initrd" Linux image when you just
3607 change a file in your "initrd"). Also, a field-upgrade of the
3608 software is easier now.
3614 Porting Linux to U-Boot based systems:
3615 ---------------------------------------
3617 U-Boot cannot save you from doing all the necessary modifications to
3618 configure the Linux device drivers for use with your target hardware
3619 (no, we don't intend to provide a full virtual machine interface to
3622 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3624 Just make sure your machine specific header file (for instance
3625 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3626 Information structure as we define in include/asm-<arch>/u-boot.h,
3627 and make sure that your definition of IMAP_ADDR uses the same value
3628 as your U-Boot configuration in CONFIG_SYS_IMMR.
3631 Configuring the Linux kernel:
3632 -----------------------------
3634 No specific requirements for U-Boot. Make sure you have some root
3635 device (initial ramdisk, NFS) for your target system.
3638 Building a Linux Image:
3639 -----------------------
3641 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3642 not used. If you use recent kernel source, a new build target
3643 "uImage" will exist which automatically builds an image usable by
3644 U-Boot. Most older kernels also have support for a "pImage" target,
3645 which was introduced for our predecessor project PPCBoot and uses a
3646 100% compatible format.
3655 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3656 encapsulate a compressed Linux kernel image with header information,
3657 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3659 * build a standard "vmlinux" kernel image (in ELF binary format):
3661 * convert the kernel into a raw binary image:
3663 ${CROSS_COMPILE}-objcopy -O binary \
3664 -R .note -R .comment \
3665 -S vmlinux linux.bin
3667 * compress the binary image:
3671 * package compressed binary image for U-Boot:
3673 mkimage -A ppc -O linux -T kernel -C gzip \
3674 -a 0 -e 0 -n "Linux Kernel Image" \
3675 -d linux.bin.gz uImage
3678 The "mkimage" tool can also be used to create ramdisk images for use
3679 with U-Boot, either separated from the Linux kernel image, or
3680 combined into one file. "mkimage" encapsulates the images with a 64
3681 byte header containing information about target architecture,
3682 operating system, image type, compression method, entry points, time
3683 stamp, CRC32 checksums, etc.
3685 "mkimage" can be called in two ways: to verify existing images and
3686 print the header information, or to build new images.
3688 In the first form (with "-l" option) mkimage lists the information
3689 contained in the header of an existing U-Boot image; this includes
3690 checksum verification:
3692 tools/mkimage -l image
3693 -l ==> list image header information
3695 The second form (with "-d" option) is used to build a U-Boot image
3696 from a "data file" which is used as image payload:
3698 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3699 -n name -d data_file image
3700 -A ==> set architecture to 'arch'
3701 -O ==> set operating system to 'os'
3702 -T ==> set image type to 'type'
3703 -C ==> set compression type 'comp'
3704 -a ==> set load address to 'addr' (hex)
3705 -e ==> set entry point to 'ep' (hex)
3706 -n ==> set image name to 'name'
3707 -d ==> use image data from 'datafile'
3709 Right now, all Linux kernels for PowerPC systems use the same load
3710 address (0x00000000), but the entry point address depends on the
3713 - 2.2.x kernels have the entry point at 0x0000000C,
3714 - 2.3.x and later kernels have the entry point at 0x00000000.
3716 So a typical call to build a U-Boot image would read:
3718 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3719 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3720 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3721 > examples/uImage.TQM850L
3722 Image Name: 2.4.4 kernel for TQM850L
3723 Created: Wed Jul 19 02:34:59 2000
3724 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3725 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3726 Load Address: 0x00000000
3727 Entry Point: 0x00000000
3729 To verify the contents of the image (or check for corruption):
3731 -> tools/mkimage -l examples/uImage.TQM850L
3732 Image Name: 2.4.4 kernel for TQM850L
3733 Created: Wed Jul 19 02:34:59 2000
3734 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3735 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3736 Load Address: 0x00000000
3737 Entry Point: 0x00000000
3739 NOTE: for embedded systems where boot time is critical you can trade
3740 speed for memory and install an UNCOMPRESSED image instead: this
3741 needs more space in Flash, but boots much faster since it does not
3742 need to be uncompressed:
3744 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3745 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3746 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3747 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3748 > examples/uImage.TQM850L-uncompressed
3749 Image Name: 2.4.4 kernel for TQM850L
3750 Created: Wed Jul 19 02:34:59 2000
3751 Image Type: PowerPC Linux Kernel Image (uncompressed)
3752 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3753 Load Address: 0x00000000
3754 Entry Point: 0x00000000
3757 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3758 when your kernel is intended to use an initial ramdisk:
3760 -> tools/mkimage -n 'Simple Ramdisk Image' \
3761 > -A ppc -O linux -T ramdisk -C gzip \
3762 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3763 Image Name: Simple Ramdisk Image
3764 Created: Wed Jan 12 14:01:50 2000
3765 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3766 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3767 Load Address: 0x00000000
3768 Entry Point: 0x00000000
3771 Installing a Linux Image:
3772 -------------------------
3774 To downloading a U-Boot image over the serial (console) interface,
3775 you must convert the image to S-Record format:
3777 objcopy -I binary -O srec examples/image examples/image.srec
3779 The 'objcopy' does not understand the information in the U-Boot
3780 image header, so the resulting S-Record file will be relative to
3781 address 0x00000000. To load it to a given address, you need to
3782 specify the target address as 'offset' parameter with the 'loads'
3785 Example: install the image to address 0x40100000 (which on the
3786 TQM8xxL is in the first Flash bank):
3788 => erase 40100000 401FFFFF
3794 ## Ready for S-Record download ...
3795 ~>examples/image.srec
3796 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3798 15989 15990 15991 15992
3799 [file transfer complete]
3801 ## Start Addr = 0x00000000
3804 You can check the success of the download using the 'iminfo' command;
3805 this includes a checksum verification so you can be sure no data
3806 corruption happened:
3810 ## Checking Image at 40100000 ...
3811 Image Name: 2.2.13 for initrd on TQM850L
3812 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3813 Data Size: 335725 Bytes = 327 kB = 0 MB
3814 Load Address: 00000000
3815 Entry Point: 0000000c
3816 Verifying Checksum ... OK
3822 The "bootm" command is used to boot an application that is stored in
3823 memory (RAM or Flash). In case of a Linux kernel image, the contents
3824 of the "bootargs" environment variable is passed to the kernel as
3825 parameters. You can check and modify this variable using the
3826 "printenv" and "setenv" commands:
3829 => printenv bootargs
3830 bootargs=root=/dev/ram
3832 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3834 => printenv bootargs
3835 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3838 ## Booting Linux kernel at 40020000 ...
3839 Image Name: 2.2.13 for NFS on TQM850L
3840 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3841 Data Size: 381681 Bytes = 372 kB = 0 MB
3842 Load Address: 00000000
3843 Entry Point: 0000000c
3844 Verifying Checksum ... OK
3845 Uncompressing Kernel Image ... OK
3846 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
3847 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3848 time_init: decrementer frequency = 187500000/60
3849 Calibrating delay loop... 49.77 BogoMIPS
3850 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3853 If you want to boot a Linux kernel with initial RAM disk, you pass
3854 the memory addresses of both the kernel and the initrd image (PPBCOOT
3855 format!) to the "bootm" command:
3857 => imi 40100000 40200000
3859 ## Checking Image at 40100000 ...
3860 Image Name: 2.2.13 for initrd on TQM850L
3861 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3862 Data Size: 335725 Bytes = 327 kB = 0 MB
3863 Load Address: 00000000
3864 Entry Point: 0000000c
3865 Verifying Checksum ... OK
3867 ## Checking Image at 40200000 ...
3868 Image Name: Simple Ramdisk Image
3869 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3870 Data Size: 566530 Bytes = 553 kB = 0 MB
3871 Load Address: 00000000
3872 Entry Point: 00000000
3873 Verifying Checksum ... OK
3875 => bootm 40100000 40200000
3876 ## Booting Linux kernel at 40100000 ...
3877 Image Name: 2.2.13 for initrd on TQM850L
3878 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3879 Data Size: 335725 Bytes = 327 kB = 0 MB
3880 Load Address: 00000000
3881 Entry Point: 0000000c
3882 Verifying Checksum ... OK
3883 Uncompressing Kernel Image ... OK
3884 ## Loading RAMDisk Image at 40200000 ...
3885 Image Name: Simple Ramdisk Image
3886 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3887 Data Size: 566530 Bytes = 553 kB = 0 MB
3888 Load Address: 00000000
3889 Entry Point: 00000000
3890 Verifying Checksum ... OK
3891 Loading Ramdisk ... OK
3892 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
3893 Boot arguments: root=/dev/ram
3894 time_init: decrementer frequency = 187500000/60
3895 Calibrating delay loop... 49.77 BogoMIPS
3897 RAMDISK: Compressed image found at block 0
3898 VFS: Mounted root (ext2 filesystem).
3902 Boot Linux and pass a flat device tree:
3905 First, U-Boot must be compiled with the appropriate defines. See the section
3906 titled "Linux Kernel Interface" above for a more in depth explanation. The
3907 following is an example of how to start a kernel and pass an updated
3913 oft=oftrees/mpc8540ads.dtb
3914 => tftp $oftaddr $oft
3915 Speed: 1000, full duplex
3917 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3918 Filename 'oftrees/mpc8540ads.dtb'.
3919 Load address: 0x300000
3922 Bytes transferred = 4106 (100a hex)
3923 => tftp $loadaddr $bootfile
3924 Speed: 1000, full duplex
3926 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3928 Load address: 0x200000
3929 Loading:############
3931 Bytes transferred = 1029407 (fb51f hex)
3936 => bootm $loadaddr - $oftaddr
3937 ## Booting image at 00200000 ...
3938 Image Name: Linux-2.6.17-dirty
3939 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3940 Data Size: 1029343 Bytes = 1005.2 kB
3941 Load Address: 00000000
3942 Entry Point: 00000000
3943 Verifying Checksum ... OK
3944 Uncompressing Kernel Image ... OK
3945 Booting using flat device tree at 0x300000
3946 Using MPC85xx ADS machine description
3947 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3951 More About U-Boot Image Types:
3952 ------------------------------
3954 U-Boot supports the following image types:
3956 "Standalone Programs" are directly runnable in the environment
3957 provided by U-Boot; it is expected that (if they behave
3958 well) you can continue to work in U-Boot after return from
3959 the Standalone Program.
3960 "OS Kernel Images" are usually images of some Embedded OS which
3961 will take over control completely. Usually these programs
3962 will install their own set of exception handlers, device
3963 drivers, set up the MMU, etc. - this means, that you cannot
3964 expect to re-enter U-Boot except by resetting the CPU.
3965 "RAMDisk Images" are more or less just data blocks, and their
3966 parameters (address, size) are passed to an OS kernel that is
3968 "Multi-File Images" contain several images, typically an OS
3969 (Linux) kernel image and one or more data images like
3970 RAMDisks. This construct is useful for instance when you want
3971 to boot over the network using BOOTP etc., where the boot
3972 server provides just a single image file, but you want to get
3973 for instance an OS kernel and a RAMDisk image.
3975 "Multi-File Images" start with a list of image sizes, each
3976 image size (in bytes) specified by an "uint32_t" in network
3977 byte order. This list is terminated by an "(uint32_t)0".
3978 Immediately after the terminating 0 follow the images, one by
3979 one, all aligned on "uint32_t" boundaries (size rounded up to
3980 a multiple of 4 bytes).
3982 "Firmware Images" are binary images containing firmware (like
3983 U-Boot or FPGA images) which usually will be programmed to
3986 "Script files" are command sequences that will be executed by
3987 U-Boot's command interpreter; this feature is especially
3988 useful when you configure U-Boot to use a real shell (hush)
3989 as command interpreter.
3995 One of the features of U-Boot is that you can dynamically load and
3996 run "standalone" applications, which can use some resources of
3997 U-Boot like console I/O functions or interrupt services.
3999 Two simple examples are included with the sources:
4004 'examples/hello_world.c' contains a small "Hello World" Demo
4005 application; it is automatically compiled when you build U-Boot.
4006 It's configured to run at address 0x00040004, so you can play with it
4010 ## Ready for S-Record download ...
4011 ~>examples/hello_world.srec
4012 1 2 3 4 5 6 7 8 9 10 11 ...
4013 [file transfer complete]
4015 ## Start Addr = 0x00040004
4017 => go 40004 Hello World! This is a test.
4018 ## Starting application at 0x00040004 ...
4029 Hit any key to exit ...
4031 ## Application terminated, rc = 0x0
4033 Another example, which demonstrates how to register a CPM interrupt
4034 handler with the U-Boot code, can be found in 'examples/timer.c'.
4035 Here, a CPM timer is set up to generate an interrupt every second.
4036 The interrupt service routine is trivial, just printing a '.'
4037 character, but this is just a demo program. The application can be
4038 controlled by the following keys:
4040 ? - print current values og the CPM Timer registers
4041 b - enable interrupts and start timer
4042 e - stop timer and disable interrupts
4043 q - quit application
4046 ## Ready for S-Record download ...
4047 ~>examples/timer.srec
4048 1 2 3 4 5 6 7 8 9 10 11 ...
4049 [file transfer complete]
4051 ## Start Addr = 0x00040004
4054 ## Starting application at 0x00040004 ...
4057 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4060 [q, b, e, ?] Set interval 1000000 us
4063 [q, b, e, ?] ........
4064 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4067 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4070 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4073 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4075 [q, b, e, ?] ...Stopping timer
4077 [q, b, e, ?] ## Application terminated, rc = 0x0
4083 Over time, many people have reported problems when trying to use the
4084 "minicom" terminal emulation program for serial download. I (wd)
4085 consider minicom to be broken, and recommend not to use it. Under
4086 Unix, I recommend to use C-Kermit for general purpose use (and
4087 especially for kermit binary protocol download ("loadb" command), and
4088 use "cu" for S-Record download ("loads" command).
4090 Nevertheless, if you absolutely want to use it try adding this
4091 configuration to your "File transfer protocols" section:
4093 Name Program Name U/D FullScr IO-Red. Multi
4094 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4095 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4101 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4102 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4104 Building requires a cross environment; it is known to work on
4105 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4106 need gmake since the Makefiles are not compatible with BSD make).
4107 Note that the cross-powerpc package does not install include files;
4108 attempting to build U-Boot will fail because <machine/ansi.h> is
4109 missing. This file has to be installed and patched manually:
4111 # cd /usr/pkg/cross/powerpc-netbsd/include
4113 # ln -s powerpc machine
4114 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4115 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4117 Native builds *don't* work due to incompatibilities between native
4118 and U-Boot include files.
4120 Booting assumes that (the first part of) the image booted is a
4121 stage-2 loader which in turn loads and then invokes the kernel
4122 proper. Loader sources will eventually appear in the NetBSD source
4123 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4124 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4127 Implementation Internals:
4128 =========================
4130 The following is not intended to be a complete description of every
4131 implementation detail. However, it should help to understand the
4132 inner workings of U-Boot and make it easier to port it to custom
4136 Initial Stack, Global Data:
4137 ---------------------------
4139 The implementation of U-Boot is complicated by the fact that U-Boot
4140 starts running out of ROM (flash memory), usually without access to
4141 system RAM (because the memory controller is not initialized yet).
4142 This means that we don't have writable Data or BSS segments, and BSS
4143 is not initialized as zero. To be able to get a C environment working
4144 at all, we have to allocate at least a minimal stack. Implementation
4145 options for this are defined and restricted by the CPU used: Some CPU
4146 models provide on-chip memory (like the IMMR area on MPC8xx and
4147 MPC826x processors), on others (parts of) the data cache can be
4148 locked as (mis-) used as memory, etc.
4150 Chris Hallinan posted a good summary of these issues to the
4151 U-Boot mailing list:
4153 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4154 From: "Chris Hallinan" <clh@net1plus.com>
4155 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4158 Correct me if I'm wrong, folks, but the way I understand it
4159 is this: Using DCACHE as initial RAM for Stack, etc, does not
4160 require any physical RAM backing up the cache. The cleverness
4161 is that the cache is being used as a temporary supply of
4162 necessary storage before the SDRAM controller is setup. It's
4163 beyond the scope of this list to explain the details, but you
4164 can see how this works by studying the cache architecture and
4165 operation in the architecture and processor-specific manuals.
4167 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4168 is another option for the system designer to use as an
4169 initial stack/RAM area prior to SDRAM being available. Either
4170 option should work for you. Using CS 4 should be fine if your
4171 board designers haven't used it for something that would
4172 cause you grief during the initial boot! It is frequently not
4175 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4176 with your processor/board/system design. The default value
4177 you will find in any recent u-boot distribution in
4178 walnut.h should work for you. I'd set it to a value larger
4179 than your SDRAM module. If you have a 64MB SDRAM module, set
4180 it above 400_0000. Just make sure your board has no resources
4181 that are supposed to respond to that address! That code in
4182 start.S has been around a while and should work as is when
4183 you get the config right.
4188 It is essential to remember this, since it has some impact on the C
4189 code for the initialization procedures:
4191 * Initialized global data (data segment) is read-only. Do not attempt
4194 * Do not use any uninitialized global data (or implicitely initialized
4195 as zero data - BSS segment) at all - this is undefined, initiali-
4196 zation is performed later (when relocating to RAM).
4198 * Stack space is very limited. Avoid big data buffers or things like
4201 Having only the stack as writable memory limits means we cannot use
4202 normal global data to share information beween the code. But it
4203 turned out that the implementation of U-Boot can be greatly
4204 simplified by making a global data structure (gd_t) available to all
4205 functions. We could pass a pointer to this data as argument to _all_
4206 functions, but this would bloat the code. Instead we use a feature of
4207 the GCC compiler (Global Register Variables) to share the data: we
4208 place a pointer (gd) to the global data into a register which we
4209 reserve for this purpose.
4211 When choosing a register for such a purpose we are restricted by the
4212 relevant (E)ABI specifications for the current architecture, and by
4213 GCC's implementation.
4215 For PowerPC, the following registers have specific use:
4217 R2: reserved for system use
4218 R3-R4: parameter passing and return values
4219 R5-R10: parameter passing
4220 R13: small data area pointer
4224 (U-Boot also uses R12 as internal GOT pointer. r12
4225 is a volatile register so r12 needs to be reset when
4226 going back and forth between asm and C)
4228 ==> U-Boot will use R2 to hold a pointer to the global data
4230 Note: on PPC, we could use a static initializer (since the
4231 address of the global data structure is known at compile time),
4232 but it turned out that reserving a register results in somewhat
4233 smaller code - although the code savings are not that big (on
4234 average for all boards 752 bytes for the whole U-Boot image,
4235 624 text + 127 data).
4237 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4238 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4240 ==> U-Boot will use P3 to hold a pointer to the global data
4242 On ARM, the following registers are used:
4244 R0: function argument word/integer result
4245 R1-R3: function argument word
4247 R10: stack limit (used only if stack checking if enabled)
4248 R11: argument (frame) pointer
4249 R12: temporary workspace
4252 R15: program counter
4254 ==> U-Boot will use R8 to hold a pointer to the global data
4256 On Nios II, the ABI is documented here:
4257 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4259 ==> U-Boot will use gp to hold a pointer to the global data
4261 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4262 to access small data sections, so gp is free.
4264 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4265 or current versions of GCC may "optimize" the code too much.
4270 U-Boot runs in system state and uses physical addresses, i.e. the
4271 MMU is not used either for address mapping nor for memory protection.
4273 The available memory is mapped to fixed addresses using the memory
4274 controller. In this process, a contiguous block is formed for each
4275 memory type (Flash, SDRAM, SRAM), even when it consists of several
4276 physical memory banks.
4278 U-Boot is installed in the first 128 kB of the first Flash bank (on
4279 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4280 booting and sizing and initializing DRAM, the code relocates itself
4281 to the upper end of DRAM. Immediately below the U-Boot code some
4282 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4283 configuration setting]. Below that, a structure with global Board
4284 Info data is placed, followed by the stack (growing downward).
4286 Additionally, some exception handler code is copied to the low 8 kB
4287 of DRAM (0x00000000 ... 0x00001FFF).
4289 So a typical memory configuration with 16 MB of DRAM could look like
4292 0x0000 0000 Exception Vector code
4295 0x0000 2000 Free for Application Use
4301 0x00FB FF20 Monitor Stack (Growing downward)
4302 0x00FB FFAC Board Info Data and permanent copy of global data
4303 0x00FC 0000 Malloc Arena
4306 0x00FE 0000 RAM Copy of Monitor Code
4307 ... eventually: LCD or video framebuffer
4308 ... eventually: pRAM (Protected RAM - unchanged by reset)
4309 0x00FF FFFF [End of RAM]
4312 System Initialization:
4313 ----------------------
4315 In the reset configuration, U-Boot starts at the reset entry point
4316 (on most PowerPC systems at address 0x00000100). Because of the reset
4317 configuration for CS0# this is a mirror of the onboard Flash memory.
4318 To be able to re-map memory U-Boot then jumps to its link address.
4319 To be able to implement the initialization code in C, a (small!)
4320 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4321 which provide such a feature like MPC8xx or MPC8260), or in a locked
4322 part of the data cache. After that, U-Boot initializes the CPU core,
4323 the caches and the SIU.
4325 Next, all (potentially) available memory banks are mapped using a
4326 preliminary mapping. For example, we put them on 512 MB boundaries
4327 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4328 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4329 programmed for SDRAM access. Using the temporary configuration, a
4330 simple memory test is run that determines the size of the SDRAM
4333 When there is more than one SDRAM bank, and the banks are of
4334 different size, the largest is mapped first. For equal size, the first
4335 bank (CS2#) is mapped first. The first mapping is always for address
4336 0x00000000, with any additional banks following immediately to create
4337 contiguous memory starting from 0.
4339 Then, the monitor installs itself at the upper end of the SDRAM area
4340 and allocates memory for use by malloc() and for the global Board
4341 Info data; also, the exception vector code is copied to the low RAM
4342 pages, and the final stack is set up.
4344 Only after this relocation will you have a "normal" C environment;
4345 until that you are restricted in several ways, mostly because you are
4346 running from ROM, and because the code will have to be relocated to a
4350 U-Boot Porting Guide:
4351 ----------------------
4353 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4357 int main(int argc, char *argv[])
4359 sighandler_t no_more_time;
4361 signal(SIGALRM, no_more_time);
4362 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4364 if (available_money > available_manpower) {
4365 Pay consultant to port U-Boot;
4369 Download latest U-Boot source;
4371 Subscribe to u-boot mailing list;
4374 email("Hi, I am new to U-Boot, how do I get started?");
4377 Read the README file in the top level directory;
4378 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4379 Read applicable doc/*.README;
4380 Read the source, Luke;
4381 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4384 if (available_money > toLocalCurrency ($2500))
4387 Add a lot of aggravation and time;
4389 if (a similar board exists) { /* hopefully... */
4390 cp -a board/<similar> board/<myboard>
4391 cp include/configs/<similar>.h include/configs/<myboard>.h
4393 Create your own board support subdirectory;
4394 Create your own board include/configs/<myboard>.h file;
4396 Edit new board/<myboard> files
4397 Edit new include/configs/<myboard>.h
4402 Add / modify source code;
4406 email("Hi, I am having problems...");
4408 Send patch file to the U-Boot email list;
4409 if (reasonable critiques)
4410 Incorporate improvements from email list code review;
4412 Defend code as written;
4418 void no_more_time (int sig)
4427 All contributions to U-Boot should conform to the Linux kernel
4428 coding style; see the file "Documentation/CodingStyle" and the script
4429 "scripts/Lindent" in your Linux kernel source directory. In sources
4430 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4431 spaces before parameters to function calls) is actually used.
4433 Source files originating from a different project (for example the
4434 MTD subsystem) are generally exempt from these guidelines and are not
4435 reformated to ease subsequent migration to newer versions of those
4438 Please note that U-Boot is implemented in C (and to some small parts in
4439 Assembler); no C++ is used, so please do not use C++ style comments (//)
4442 Please also stick to the following formatting rules:
4443 - remove any trailing white space
4444 - use TAB characters for indentation, not spaces
4445 - make sure NOT to use DOS '\r\n' line feeds
4446 - do not add more than 2 empty lines to source files
4447 - do not add trailing empty lines to source files
4449 Submissions which do not conform to the standards may be returned
4450 with a request to reformat the changes.
4456 Since the number of patches for U-Boot is growing, we need to
4457 establish some rules. Submissions which do not conform to these rules
4458 may be rejected, even when they contain important and valuable stuff.
4460 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4462 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4463 see http://lists.denx.de/mailman/listinfo/u-boot
4465 When you send a patch, please include the following information with
4468 * For bug fixes: a description of the bug and how your patch fixes
4469 this bug. Please try to include a way of demonstrating that the
4470 patch actually fixes something.
4472 * For new features: a description of the feature and your
4475 * A CHANGELOG entry as plaintext (separate from the patch)
4477 * For major contributions, your entry to the CREDITS file
4479 * When you add support for a new board, don't forget to add this
4480 board to the MAKEALL script, too.
4482 * If your patch adds new configuration options, don't forget to
4483 document these in the README file.
4485 * The patch itself. If you are using git (which is *strongly*
4486 recommended) you can easily generate the patch using the
4487 "git-format-patch". If you then use "git-send-email" to send it to
4488 the U-Boot mailing list, you will avoid most of the common problems
4489 with some other mail clients.
4491 If you cannot use git, use "diff -purN OLD NEW". If your version of
4492 diff does not support these options, then get the latest version of
4495 The current directory when running this command shall be the parent
4496 directory of the U-Boot source tree (i. e. please make sure that
4497 your patch includes sufficient directory information for the
4500 We prefer patches as plain text. MIME attachments are discouraged,
4501 and compressed attachments must not be used.
4503 * If one logical set of modifications affects or creates several
4504 files, all these changes shall be submitted in a SINGLE patch file.
4506 * Changesets that contain different, unrelated modifications shall be
4507 submitted as SEPARATE patches, one patch per changeset.
4512 * Before sending the patch, run the MAKEALL script on your patched
4513 source tree and make sure that no errors or warnings are reported
4514 for any of the boards.
4516 * Keep your modifications to the necessary minimum: A patch
4517 containing several unrelated changes or arbitrary reformats will be
4518 returned with a request to re-formatting / split it.
4520 * If you modify existing code, make sure that your new code does not
4521 add to the memory footprint of the code ;-) Small is beautiful!
4522 When adding new features, these should compile conditionally only
4523 (using #ifdef), and the resulting code with the new feature
4524 disabled must not need more memory than the old code without your
4527 * Remember that there is a size limit of 100 kB per message on the
4528 u-boot mailing list. Bigger patches will be moderated. If they are
4529 reasonable and not too big, they will be acknowledged. But patches
4530 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob