2 # (C) Copyright 2000 - 2011
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
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.
1068 Support for Renesas on-chip MMCIF controller
1070 CONFIG_SH_MMCIF_ADDR
1071 Define the base address of MMCIF registers
1074 Define the clock frequency for MMCIF
1076 - Journaling Flash filesystem support:
1077 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1078 CONFIG_JFFS2_NAND_DEV
1079 Define these for a default partition on a NAND device
1081 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1082 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1083 Define these for a default partition on a NOR device
1085 CONFIG_SYS_JFFS_CUSTOM_PART
1086 Define this to create an own partition. You have to provide a
1087 function struct part_info* jffs2_part_info(int part_num)
1089 If you define only one JFFS2 partition you may also want to
1090 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1091 to disable the command chpart. This is the default when you
1092 have not defined a custom partition
1097 Define this to enable standard (PC-Style) keyboard
1101 Standard PC keyboard driver with US (is default) and
1102 GERMAN key layout (switch via environment 'keymap=de') support.
1103 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1104 for cfb_console. Supports cursor blinking.
1109 Define this to enable video support (for output to
1112 CONFIG_VIDEO_CT69000
1114 Enable Chips & Technologies 69000 Video chip
1116 CONFIG_VIDEO_SMI_LYNXEM
1117 Enable Silicon Motion SMI 712/710/810 Video chip. The
1118 video output is selected via environment 'videoout'
1119 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1122 For the CT69000 and SMI_LYNXEM drivers, videomode is
1123 selected via environment 'videomode'. Two different ways
1125 - "videomode=num" 'num' is a standard LiLo mode numbers.
1126 Following standard modes are supported (* is default):
1128 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1129 -------------+---------------------------------------------
1130 8 bits | 0x301* 0x303 0x305 0x161 0x307
1131 15 bits | 0x310 0x313 0x316 0x162 0x319
1132 16 bits | 0x311 0x314 0x317 0x163 0x31A
1133 24 bits | 0x312 0x315 0x318 ? 0x31B
1134 -------------+---------------------------------------------
1135 (i.e. setenv videomode 317; saveenv; reset;)
1137 - "videomode=bootargs" all the video parameters are parsed
1138 from the bootargs. (See drivers/video/videomodes.c)
1141 CONFIG_VIDEO_SED13806
1142 Enable Epson SED13806 driver. This driver supports 8bpp
1143 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1144 or CONFIG_VIDEO_SED13806_16BPP
1147 Enable the Freescale DIU video driver. Reference boards for
1148 SOCs that have a DIU should define this macro to enable DIU
1149 support, and should also define these other macros:
1155 CONFIG_VIDEO_SW_CURSOR
1156 CONFIG_VGA_AS_SINGLE_DEVICE
1158 CONFIG_VIDEO_BMP_LOGO
1160 The DIU driver will look for the 'video-mode' environment
1161 variable, and if defined, enable the DIU as a console during
1162 boot. See the documentation file README.video for a
1163 description of this variable.
1168 Define this to enable a custom keyboard support.
1169 This simply calls drv_keyboard_init() which must be
1170 defined in your board-specific files.
1171 The only board using this so far is RBC823.
1173 - LCD Support: CONFIG_LCD
1175 Define this to enable LCD support (for output to LCD
1176 display); also select one of the supported displays
1177 by defining one of these:
1181 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1183 CONFIG_NEC_NL6448AC33:
1185 NEC NL6448AC33-18. Active, color, single scan.
1187 CONFIG_NEC_NL6448BC20
1189 NEC NL6448BC20-08. 6.5", 640x480.
1190 Active, color, single scan.
1192 CONFIG_NEC_NL6448BC33_54
1194 NEC NL6448BC33-54. 10.4", 640x480.
1195 Active, color, single scan.
1199 Sharp 320x240. Active, color, single scan.
1200 It isn't 16x9, and I am not sure what it is.
1202 CONFIG_SHARP_LQ64D341
1204 Sharp LQ64D341 display, 640x480.
1205 Active, color, single scan.
1209 HLD1045 display, 640x480.
1210 Active, color, single scan.
1214 Optrex CBL50840-2 NF-FW 99 22 M5
1216 Hitachi LMG6912RPFC-00T
1220 320x240. Black & white.
1222 Normally display is black on white background; define
1223 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1225 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1227 If this option is set, the environment is checked for
1228 a variable "splashimage". If found, the usual display
1229 of logo, copyright and system information on the LCD
1230 is suppressed and the BMP image at the address
1231 specified in "splashimage" is loaded instead. The
1232 console is redirected to the "nulldev", too. This
1233 allows for a "silent" boot where a splash screen is
1234 loaded very quickly after power-on.
1236 CONFIG_SPLASH_SCREEN_ALIGN
1238 If this option is set the splash image can be freely positioned
1239 on the screen. Environment variable "splashpos" specifies the
1240 position as "x,y". If a positive number is given it is used as
1241 number of pixel from left/top. If a negative number is given it
1242 is used as number of pixel from right/bottom. You can also
1243 specify 'm' for centering the image.
1246 setenv splashpos m,m
1247 => image at center of screen
1249 setenv splashpos 30,20
1250 => image at x = 30 and y = 20
1252 setenv splashpos -10,m
1253 => vertically centered image
1254 at x = dspWidth - bmpWidth - 9
1256 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1258 If this option is set, additionally to standard BMP
1259 images, gzipped BMP images can be displayed via the
1260 splashscreen support or the bmp command.
1262 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1264 If this option is set, 8-bit RLE compressed BMP images
1265 can be displayed via the splashscreen support or the
1268 - Compression support:
1271 If this option is set, support for bzip2 compressed
1272 images is included. If not, only uncompressed and gzip
1273 compressed images are supported.
1275 NOTE: the bzip2 algorithm requires a lot of RAM, so
1276 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1281 If this option is set, support for lzma compressed
1284 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1285 requires an amount of dynamic memory that is given by the
1288 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1290 Where lc and lp stand for, respectively, Literal context bits
1291 and Literal pos bits.
1293 This value is upper-bounded by 14MB in the worst case. Anyway,
1294 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1295 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1296 a very small buffer.
1298 Use the lzmainfo tool to determinate the lc and lp values and
1299 then calculate the amount of needed dynamic memory (ensuring
1300 the appropriate CONFIG_SYS_MALLOC_LEN value).
1305 The address of PHY on MII bus.
1307 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1309 The clock frequency of the MII bus
1313 If this option is set, support for speed/duplex
1314 detection of gigabit PHY is included.
1316 CONFIG_PHY_RESET_DELAY
1318 Some PHY like Intel LXT971A need extra delay after
1319 reset before any MII register access is possible.
1320 For such PHY, set this option to the usec delay
1321 required. (minimum 300usec for LXT971A)
1323 CONFIG_PHY_CMD_DELAY (ppc4xx)
1325 Some PHY like Intel LXT971A need extra delay after
1326 command issued before MII status register can be read
1336 Define a default value for Ethernet address to use
1337 for the respective Ethernet interface, in case this
1338 is not determined automatically.
1343 Define a default value for the IP address to use for
1344 the default Ethernet interface, in case this is not
1345 determined through e.g. bootp.
1347 - Server IP address:
1350 Defines a default value for the IP address of a TFTP
1351 server to contact when using the "tftboot" command.
1353 CONFIG_KEEP_SERVERADDR
1355 Keeps the server's MAC address, in the env 'serveraddr'
1356 for passing to bootargs (like Linux's netconsole option)
1358 - Multicast TFTP Mode:
1361 Defines whether you want to support multicast TFTP as per
1362 rfc-2090; for example to work with atftp. Lets lots of targets
1363 tftp down the same boot image concurrently. Note: the Ethernet
1364 driver in use must provide a function: mcast() to join/leave a
1367 - BOOTP Recovery Mode:
1368 CONFIG_BOOTP_RANDOM_DELAY
1370 If you have many targets in a network that try to
1371 boot using BOOTP, you may want to avoid that all
1372 systems send out BOOTP requests at precisely the same
1373 moment (which would happen for instance at recovery
1374 from a power failure, when all systems will try to
1375 boot, thus flooding the BOOTP server. Defining
1376 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1377 inserted before sending out BOOTP requests. The
1378 following delays are inserted then:
1380 1st BOOTP request: delay 0 ... 1 sec
1381 2nd BOOTP request: delay 0 ... 2 sec
1382 3rd BOOTP request: delay 0 ... 4 sec
1384 BOOTP requests: delay 0 ... 8 sec
1386 - DHCP Advanced Options:
1387 You can fine tune the DHCP functionality by defining
1388 CONFIG_BOOTP_* symbols:
1390 CONFIG_BOOTP_SUBNETMASK
1391 CONFIG_BOOTP_GATEWAY
1392 CONFIG_BOOTP_HOSTNAME
1393 CONFIG_BOOTP_NISDOMAIN
1394 CONFIG_BOOTP_BOOTPATH
1395 CONFIG_BOOTP_BOOTFILESIZE
1398 CONFIG_BOOTP_SEND_HOSTNAME
1399 CONFIG_BOOTP_NTPSERVER
1400 CONFIG_BOOTP_TIMEOFFSET
1401 CONFIG_BOOTP_VENDOREX
1403 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1404 environment variable, not the BOOTP server.
1406 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1407 serverip from a DHCP server, it is possible that more
1408 than one DNS serverip is offered to the client.
1409 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1410 serverip will be stored in the additional environment
1411 variable "dnsip2". The first DNS serverip is always
1412 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1415 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1416 to do a dynamic update of a DNS server. To do this, they
1417 need the hostname of the DHCP requester.
1418 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1419 of the "hostname" environment variable is passed as
1420 option 12 to the DHCP server.
1422 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1424 A 32bit value in microseconds for a delay between
1425 receiving a "DHCP Offer" and sending the "DHCP Request".
1426 This fixes a problem with certain DHCP servers that don't
1427 respond 100% of the time to a "DHCP request". E.g. On an
1428 AT91RM9200 processor running at 180MHz, this delay needed
1429 to be *at least* 15,000 usec before a Windows Server 2003
1430 DHCP server would reply 100% of the time. I recommend at
1431 least 50,000 usec to be safe. The alternative is to hope
1432 that one of the retries will be successful but note that
1433 the DHCP timeout and retry process takes a longer than
1437 CONFIG_CDP_DEVICE_ID
1439 The device id used in CDP trigger frames.
1441 CONFIG_CDP_DEVICE_ID_PREFIX
1443 A two character string which is prefixed to the MAC address
1448 A printf format string which contains the ascii name of
1449 the port. Normally is set to "eth%d" which sets
1450 eth0 for the first Ethernet, eth1 for the second etc.
1452 CONFIG_CDP_CAPABILITIES
1454 A 32bit integer which indicates the device capabilities;
1455 0x00000010 for a normal host which does not forwards.
1459 An ascii string containing the version of the software.
1463 An ascii string containing the name of the platform.
1467 A 32bit integer sent on the trigger.
1469 CONFIG_CDP_POWER_CONSUMPTION
1471 A 16bit integer containing the power consumption of the
1472 device in .1 of milliwatts.
1474 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1476 A byte containing the id of the VLAN.
1478 - Status LED: CONFIG_STATUS_LED
1480 Several configurations allow to display the current
1481 status using a LED. For instance, the LED will blink
1482 fast while running U-Boot code, stop blinking as
1483 soon as a reply to a BOOTP request was received, and
1484 start blinking slow once the Linux kernel is running
1485 (supported by a status LED driver in the Linux
1486 kernel). Defining CONFIG_STATUS_LED enables this
1489 - CAN Support: CONFIG_CAN_DRIVER
1491 Defining CONFIG_CAN_DRIVER enables CAN driver support
1492 on those systems that support this (optional)
1493 feature, like the TQM8xxL modules.
1495 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1497 These enable I2C serial bus commands. Defining either of
1498 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1499 include the appropriate I2C driver for the selected CPU.
1501 This will allow you to use i2c commands at the u-boot
1502 command line (as long as you set CONFIG_CMD_I2C in
1503 CONFIG_COMMANDS) and communicate with i2c based realtime
1504 clock chips. See common/cmd_i2c.c for a description of the
1505 command line interface.
1507 CONFIG_HARD_I2C selects a hardware I2C controller.
1509 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1510 bit-banging) driver instead of CPM or similar hardware
1513 There are several other quantities that must also be
1514 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1516 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1517 to be the frequency (in Hz) at which you wish your i2c bus
1518 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1519 the CPU's i2c node address).
1521 Now, the u-boot i2c code for the mpc8xx
1522 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1523 and so its address should therefore be cleared to 0 (See,
1524 eg, MPC823e User's Manual p.16-473). So, set
1525 CONFIG_SYS_I2C_SLAVE to 0.
1527 CONFIG_SYS_I2C_INIT_MPC5XXX
1529 When a board is reset during an i2c bus transfer
1530 chips might think that the current transfer is still
1531 in progress. Reset the slave devices by sending start
1532 commands until the slave device responds.
1534 That's all that's required for CONFIG_HARD_I2C.
1536 If you use the software i2c interface (CONFIG_SOFT_I2C)
1537 then the following macros need to be defined (examples are
1538 from include/configs/lwmon.h):
1542 (Optional). Any commands necessary to enable the I2C
1543 controller or configure ports.
1545 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1549 (Only for MPC8260 CPU). The I/O port to use (the code
1550 assumes both bits are on the same port). Valid values
1551 are 0..3 for ports A..D.
1555 The code necessary to make the I2C data line active
1556 (driven). If the data line is open collector, this
1559 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1563 The code necessary to make the I2C data line tri-stated
1564 (inactive). If the data line is open collector, this
1567 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1571 Code that returns TRUE if the I2C data line is high,
1574 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1578 If <bit> is TRUE, sets the I2C data line high. If it
1579 is FALSE, it clears it (low).
1581 eg: #define I2C_SDA(bit) \
1582 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1583 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1587 If <bit> is TRUE, sets the I2C clock line high. If it
1588 is FALSE, it clears it (low).
1590 eg: #define I2C_SCL(bit) \
1591 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1592 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1596 This delay is invoked four times per clock cycle so this
1597 controls the rate of data transfer. The data rate thus
1598 is 1 / (I2C_DELAY * 4). Often defined to be something
1601 #define I2C_DELAY udelay(2)
1603 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1605 If your arch supports the generic GPIO framework (asm/gpio.h),
1606 then you may alternatively define the two GPIOs that are to be
1607 used as SCL / SDA. Any of the previous I2C_xxx macros will
1608 have GPIO-based defaults assigned to them as appropriate.
1610 You should define these to the GPIO value as given directly to
1611 the generic GPIO functions.
1613 CONFIG_SYS_I2C_INIT_BOARD
1615 When a board is reset during an i2c bus transfer
1616 chips might think that the current transfer is still
1617 in progress. On some boards it is possible to access
1618 the i2c SCLK line directly, either by using the
1619 processor pin as a GPIO or by having a second pin
1620 connected to the bus. If this option is defined a
1621 custom i2c_init_board() routine in boards/xxx/board.c
1622 is run early in the boot sequence.
1624 CONFIG_SYS_I2C_BOARD_LATE_INIT
1626 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1627 defined a custom i2c_board_late_init() routine in
1628 boards/xxx/board.c is run AFTER the operations in i2c_init()
1629 is completed. This callpoint can be used to unreset i2c bus
1630 using CPU i2c controller register accesses for CPUs whose i2c
1631 controller provide such a method. It is called at the end of
1632 i2c_init() to allow i2c_init operations to setup the i2c bus
1633 controller on the CPU (e.g. setting bus speed & slave address).
1635 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1637 This option enables configuration of bi_iic_fast[] flags
1638 in u-boot bd_info structure based on u-boot environment
1639 variable "i2cfast". (see also i2cfast)
1641 CONFIG_I2C_MULTI_BUS
1643 This option allows the use of multiple I2C buses, each of which
1644 must have a controller. At any point in time, only one bus is
1645 active. To switch to a different bus, use the 'i2c dev' command.
1646 Note that bus numbering is zero-based.
1648 CONFIG_SYS_I2C_NOPROBES
1650 This option specifies a list of I2C devices that will be skipped
1651 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1652 is set, specify a list of bus-device pairs. Otherwise, specify
1653 a 1D array of device addresses
1656 #undef CONFIG_I2C_MULTI_BUS
1657 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1659 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1661 #define CONFIG_I2C_MULTI_BUS
1662 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1664 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1666 CONFIG_SYS_SPD_BUS_NUM
1668 If defined, then this indicates the I2C bus number for DDR SPD.
1669 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1671 CONFIG_SYS_RTC_BUS_NUM
1673 If defined, then this indicates the I2C bus number for the RTC.
1674 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1676 CONFIG_SYS_DTT_BUS_NUM
1678 If defined, then this indicates the I2C bus number for the DTT.
1679 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1681 CONFIG_SYS_I2C_DTT_ADDR:
1683 If defined, specifies the I2C address of the DTT device.
1684 If not defined, then U-Boot uses predefined value for
1685 specified DTT device.
1689 Define this option if you want to use Freescale's I2C driver in
1690 drivers/i2c/fsl_i2c.c.
1694 Define this option if you have I2C devices reached over 1 .. n
1695 I2C Muxes like the pca9544a. This option addes a new I2C
1696 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1697 new I2C Bus to the existing I2C Busses. If you select the
1698 new Bus with "i2c dev", u-bbot sends first the commandos for
1699 the muxes to activate this new "bus".
1701 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1705 Adding a new I2C Bus reached over 2 pca9544a muxes
1706 The First mux with address 70 and channel 6
1707 The Second mux with address 71 and channel 4
1709 => i2c bus pca9544a:70:6:pca9544a:71:4
1711 Use the "i2c bus" command without parameter, to get a list
1712 of I2C Busses with muxes:
1715 Busses reached over muxes:
1717 reached over Mux(es):
1720 reached over Mux(es):
1725 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1726 u-boot first sends the command to the mux@70 to enable
1727 channel 6, and then the command to the mux@71 to enable
1730 After that, you can use the "normal" i2c commands as
1731 usual to communicate with your I2C devices behind
1734 This option is actually implemented for the bitbanging
1735 algorithm in common/soft_i2c.c and for the Hardware I2C
1736 Bus on the MPC8260. But it should be not so difficult
1737 to add this option to other architectures.
1739 CONFIG_SOFT_I2C_READ_REPEATED_START
1741 defining this will force the i2c_read() function in
1742 the soft_i2c driver to perform an I2C repeated start
1743 between writing the address pointer and reading the
1744 data. If this define is omitted the default behaviour
1745 of doing a stop-start sequence will be used. Most I2C
1746 devices can use either method, but some require one or
1749 - SPI Support: CONFIG_SPI
1751 Enables SPI driver (so far only tested with
1752 SPI EEPROM, also an instance works with Crystal A/D and
1753 D/As on the SACSng board)
1757 Enables the driver for SPI controller on SuperH. Currently
1758 only SH7757 is supported.
1762 Enables extended (16-bit) SPI EEPROM addressing.
1763 (symmetrical to CONFIG_I2C_X)
1767 Enables a software (bit-bang) SPI driver rather than
1768 using hardware support. This is a general purpose
1769 driver that only requires three general I/O port pins
1770 (two outputs, one input) to function. If this is
1771 defined, the board configuration must define several
1772 SPI configuration items (port pins to use, etc). For
1773 an example, see include/configs/sacsng.h.
1777 Enables a hardware SPI driver for general-purpose reads
1778 and writes. As with CONFIG_SOFT_SPI, the board configuration
1779 must define a list of chip-select function pointers.
1780 Currently supported on some MPC8xxx processors. For an
1781 example, see include/configs/mpc8349emds.h.
1785 Enables the driver for the SPI controllers on i.MX and MXC
1786 SoCs. Currently only i.MX31 is supported.
1788 - FPGA Support: CONFIG_FPGA
1790 Enables FPGA subsystem.
1792 CONFIG_FPGA_<vendor>
1794 Enables support for specific chip vendors.
1797 CONFIG_FPGA_<family>
1799 Enables support for FPGA family.
1800 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1804 Specify the number of FPGA devices to support.
1806 CONFIG_SYS_FPGA_PROG_FEEDBACK
1808 Enable printing of hash marks during FPGA configuration.
1810 CONFIG_SYS_FPGA_CHECK_BUSY
1812 Enable checks on FPGA configuration interface busy
1813 status by the configuration function. This option
1814 will require a board or device specific function to
1819 If defined, a function that provides delays in the FPGA
1820 configuration driver.
1822 CONFIG_SYS_FPGA_CHECK_CTRLC
1823 Allow Control-C to interrupt FPGA configuration
1825 CONFIG_SYS_FPGA_CHECK_ERROR
1827 Check for configuration errors during FPGA bitfile
1828 loading. For example, abort during Virtex II
1829 configuration if the INIT_B line goes low (which
1830 indicated a CRC error).
1832 CONFIG_SYS_FPGA_WAIT_INIT
1834 Maximum time to wait for the INIT_B line to deassert
1835 after PROB_B has been deasserted during a Virtex II
1836 FPGA configuration sequence. The default time is 500
1839 CONFIG_SYS_FPGA_WAIT_BUSY
1841 Maximum time to wait for BUSY to deassert during
1842 Virtex II FPGA configuration. The default is 5 ms.
1844 CONFIG_SYS_FPGA_WAIT_CONFIG
1846 Time to wait after FPGA configuration. The default is
1849 - Configuration Management:
1852 If defined, this string will be added to the U-Boot
1853 version information (U_BOOT_VERSION)
1855 - Vendor Parameter Protection:
1857 U-Boot considers the values of the environment
1858 variables "serial#" (Board Serial Number) and
1859 "ethaddr" (Ethernet Address) to be parameters that
1860 are set once by the board vendor / manufacturer, and
1861 protects these variables from casual modification by
1862 the user. Once set, these variables are read-only,
1863 and write or delete attempts are rejected. You can
1864 change this behaviour:
1866 If CONFIG_ENV_OVERWRITE is #defined in your config
1867 file, the write protection for vendor parameters is
1868 completely disabled. Anybody can change or delete
1871 Alternatively, if you #define _both_ CONFIG_ETHADDR
1872 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1873 Ethernet address is installed in the environment,
1874 which can be changed exactly ONCE by the user. [The
1875 serial# is unaffected by this, i. e. it remains
1881 Define this variable to enable the reservation of
1882 "protected RAM", i. e. RAM which is not overwritten
1883 by U-Boot. Define CONFIG_PRAM to hold the number of
1884 kB you want to reserve for pRAM. You can overwrite
1885 this default value by defining an environment
1886 variable "pram" to the number of kB you want to
1887 reserve. Note that the board info structure will
1888 still show the full amount of RAM. If pRAM is
1889 reserved, a new environment variable "mem" will
1890 automatically be defined to hold the amount of
1891 remaining RAM in a form that can be passed as boot
1892 argument to Linux, for instance like that:
1894 setenv bootargs ... mem=\${mem}
1897 This way you can tell Linux not to use this memory,
1898 either, which results in a memory region that will
1899 not be affected by reboots.
1901 *WARNING* If your board configuration uses automatic
1902 detection of the RAM size, you must make sure that
1903 this memory test is non-destructive. So far, the
1904 following board configurations are known to be
1907 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1908 HERMES, IP860, RPXlite, LWMON, LANTEC,
1914 Define this variable to stop the system in case of a
1915 fatal error, so that you have to reset it manually.
1916 This is probably NOT a good idea for an embedded
1917 system where you want the system to reboot
1918 automatically as fast as possible, but it may be
1919 useful during development since you can try to debug
1920 the conditions that lead to the situation.
1922 CONFIG_NET_RETRY_COUNT
1924 This variable defines the number of retries for
1925 network operations like ARP, RARP, TFTP, or BOOTP
1926 before giving up the operation. If not defined, a
1927 default value of 5 is used.
1931 Timeout waiting for an ARP reply in milliseconds.
1933 - Command Interpreter:
1934 CONFIG_AUTO_COMPLETE
1936 Enable auto completion of commands using TAB.
1938 Note that this feature has NOT been implemented yet
1939 for the "hush" shell.
1942 CONFIG_SYS_HUSH_PARSER
1944 Define this variable to enable the "hush" shell (from
1945 Busybox) as command line interpreter, thus enabling
1946 powerful command line syntax like
1947 if...then...else...fi conditionals or `&&' and '||'
1948 constructs ("shell scripts").
1950 If undefined, you get the old, much simpler behaviour
1951 with a somewhat smaller memory footprint.
1954 CONFIG_SYS_PROMPT_HUSH_PS2
1956 This defines the secondary prompt string, which is
1957 printed when the command interpreter needs more input
1958 to complete a command. Usually "> ".
1962 In the current implementation, the local variables
1963 space and global environment variables space are
1964 separated. Local variables are those you define by
1965 simply typing `name=value'. To access a local
1966 variable later on, you have write `$name' or
1967 `${name}'; to execute the contents of a variable
1968 directly type `$name' at the command prompt.
1970 Global environment variables are those you use
1971 setenv/printenv to work with. To run a command stored
1972 in such a variable, you need to use the run command,
1973 and you must not use the '$' sign to access them.
1975 To store commands and special characters in a
1976 variable, please use double quotation marks
1977 surrounding the whole text of the variable, instead
1978 of the backslashes before semicolons and special
1981 - Commandline Editing and History:
1982 CONFIG_CMDLINE_EDITING
1984 Enable editing and History functions for interactive
1985 commandline input operations
1987 - Default Environment:
1988 CONFIG_EXTRA_ENV_SETTINGS
1990 Define this to contain any number of null terminated
1991 strings (variable = value pairs) that will be part of
1992 the default environment compiled into the boot image.
1994 For example, place something like this in your
1995 board's config file:
1997 #define CONFIG_EXTRA_ENV_SETTINGS \
2001 Warning: This method is based on knowledge about the
2002 internal format how the environment is stored by the
2003 U-Boot code. This is NOT an official, exported
2004 interface! Although it is unlikely that this format
2005 will change soon, there is no guarantee either.
2006 You better know what you are doing here.
2008 Note: overly (ab)use of the default environment is
2009 discouraged. Make sure to check other ways to preset
2010 the environment like the "source" command or the
2013 - DataFlash Support:
2014 CONFIG_HAS_DATAFLASH
2016 Defining this option enables DataFlash features and
2017 allows to read/write in Dataflash via the standard
2020 - SystemACE Support:
2023 Adding this option adds support for Xilinx SystemACE
2024 chips attached via some sort of local bus. The address
2025 of the chip must also be defined in the
2026 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2028 #define CONFIG_SYSTEMACE
2029 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2031 When SystemACE support is added, the "ace" device type
2032 becomes available to the fat commands, i.e. fatls.
2034 - TFTP Fixed UDP Port:
2037 If this is defined, the environment variable tftpsrcp
2038 is used to supply the TFTP UDP source port value.
2039 If tftpsrcp isn't defined, the normal pseudo-random port
2040 number generator is used.
2042 Also, the environment variable tftpdstp is used to supply
2043 the TFTP UDP destination port value. If tftpdstp isn't
2044 defined, the normal port 69 is used.
2046 The purpose for tftpsrcp is to allow a TFTP server to
2047 blindly start the TFTP transfer using the pre-configured
2048 target IP address and UDP port. This has the effect of
2049 "punching through" the (Windows XP) firewall, allowing
2050 the remainder of the TFTP transfer to proceed normally.
2051 A better solution is to properly configure the firewall,
2052 but sometimes that is not allowed.
2054 - Show boot progress:
2055 CONFIG_SHOW_BOOT_PROGRESS
2057 Defining this option allows to add some board-
2058 specific code (calling a user-provided function
2059 "show_boot_progress(int)") that enables you to show
2060 the system's boot progress on some display (for
2061 example, some LED's) on your board. At the moment,
2062 the following checkpoints are implemented:
2064 - Standalone program support:
2065 CONFIG_STANDALONE_LOAD_ADDR
2067 This option allows to define board specific values
2068 for the address where standalone program gets loaded,
2069 thus overwriting the architecutre dependent default
2072 - Frame Buffer Address:
2075 Define CONFIG_FB_ADDR if you want to use specific address for
2077 Then system will reserve the frame buffer address to defined address
2078 instead of lcd_setmem (this function grab the memory for frame buffer
2081 Please see board_init_f function.
2083 If you want this config option then,
2084 please define it at your board config file
2086 Legacy uImage format:
2089 1 common/cmd_bootm.c before attempting to boot an image
2090 -1 common/cmd_bootm.c Image header has bad magic number
2091 2 common/cmd_bootm.c Image header has correct magic number
2092 -2 common/cmd_bootm.c Image header has bad checksum
2093 3 common/cmd_bootm.c Image header has correct checksum
2094 -3 common/cmd_bootm.c Image data has bad checksum
2095 4 common/cmd_bootm.c Image data has correct checksum
2096 -4 common/cmd_bootm.c Image is for unsupported architecture
2097 5 common/cmd_bootm.c Architecture check OK
2098 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2099 6 common/cmd_bootm.c Image Type check OK
2100 -6 common/cmd_bootm.c gunzip uncompression error
2101 -7 common/cmd_bootm.c Unimplemented compression type
2102 7 common/cmd_bootm.c Uncompression OK
2103 8 common/cmd_bootm.c No uncompress/copy overwrite error
2104 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2106 9 common/image.c Start initial ramdisk verification
2107 -10 common/image.c Ramdisk header has bad magic number
2108 -11 common/image.c Ramdisk header has bad checksum
2109 10 common/image.c Ramdisk header is OK
2110 -12 common/image.c Ramdisk data has bad checksum
2111 11 common/image.c Ramdisk data has correct checksum
2112 12 common/image.c Ramdisk verification complete, start loading
2113 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2114 13 common/image.c Start multifile image verification
2115 14 common/image.c No initial ramdisk, no multifile, continue.
2117 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2119 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2120 -31 post/post.c POST test failed, detected by post_output_backlog()
2121 -32 post/post.c POST test failed, detected by post_run_single()
2123 34 common/cmd_doc.c before loading a Image from a DOC device
2124 -35 common/cmd_doc.c Bad usage of "doc" command
2125 35 common/cmd_doc.c correct usage of "doc" command
2126 -36 common/cmd_doc.c No boot device
2127 36 common/cmd_doc.c correct boot device
2128 -37 common/cmd_doc.c Unknown Chip ID on boot device
2129 37 common/cmd_doc.c correct chip ID found, device available
2130 -38 common/cmd_doc.c Read Error on boot device
2131 38 common/cmd_doc.c reading Image header from DOC device OK
2132 -39 common/cmd_doc.c Image header has bad magic number
2133 39 common/cmd_doc.c Image header has correct magic number
2134 -40 common/cmd_doc.c Error reading Image from DOC device
2135 40 common/cmd_doc.c Image header has correct magic number
2136 41 common/cmd_ide.c before loading a Image from a IDE device
2137 -42 common/cmd_ide.c Bad usage of "ide" command
2138 42 common/cmd_ide.c correct usage of "ide" command
2139 -43 common/cmd_ide.c No boot device
2140 43 common/cmd_ide.c boot device found
2141 -44 common/cmd_ide.c Device not available
2142 44 common/cmd_ide.c Device available
2143 -45 common/cmd_ide.c wrong partition selected
2144 45 common/cmd_ide.c partition selected
2145 -46 common/cmd_ide.c Unknown partition table
2146 46 common/cmd_ide.c valid partition table found
2147 -47 common/cmd_ide.c Invalid partition type
2148 47 common/cmd_ide.c correct partition type
2149 -48 common/cmd_ide.c Error reading Image Header on boot device
2150 48 common/cmd_ide.c reading Image Header from IDE device OK
2151 -49 common/cmd_ide.c Image header has bad magic number
2152 49 common/cmd_ide.c Image header has correct magic number
2153 -50 common/cmd_ide.c Image header has bad checksum
2154 50 common/cmd_ide.c Image header has correct checksum
2155 -51 common/cmd_ide.c Error reading Image from IDE device
2156 51 common/cmd_ide.c reading Image from IDE device OK
2157 52 common/cmd_nand.c before loading a Image from a NAND device
2158 -53 common/cmd_nand.c Bad usage of "nand" command
2159 53 common/cmd_nand.c correct usage of "nand" command
2160 -54 common/cmd_nand.c No boot device
2161 54 common/cmd_nand.c boot device found
2162 -55 common/cmd_nand.c Unknown Chip ID on boot device
2163 55 common/cmd_nand.c correct chip ID found, device available
2164 -56 common/cmd_nand.c Error reading Image Header on boot device
2165 56 common/cmd_nand.c reading Image Header from NAND device OK
2166 -57 common/cmd_nand.c Image header has bad magic number
2167 57 common/cmd_nand.c Image header has correct magic number
2168 -58 common/cmd_nand.c Error reading Image from NAND device
2169 58 common/cmd_nand.c reading Image from NAND device OK
2171 -60 common/env_common.c Environment has a bad CRC, using default
2173 64 net/eth.c starting with Ethernet configuration.
2174 -64 net/eth.c no Ethernet found.
2175 65 net/eth.c Ethernet found.
2177 -80 common/cmd_net.c usage wrong
2178 80 common/cmd_net.c before calling NetLoop()
2179 -81 common/cmd_net.c some error in NetLoop() occurred
2180 81 common/cmd_net.c NetLoop() back without error
2181 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2182 82 common/cmd_net.c trying automatic boot
2183 83 common/cmd_net.c running "source" command
2184 -83 common/cmd_net.c some error in automatic boot or "source" command
2185 84 common/cmd_net.c end without errors
2190 100 common/cmd_bootm.c Kernel FIT Image has correct format
2191 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2192 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2193 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2194 102 common/cmd_bootm.c Kernel unit name specified
2195 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2196 103 common/cmd_bootm.c Found configuration node
2197 104 common/cmd_bootm.c Got kernel subimage node offset
2198 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2199 105 common/cmd_bootm.c Kernel subimage hash verification OK
2200 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2201 106 common/cmd_bootm.c Architecture check OK
2202 -106 common/cmd_bootm.c Kernel subimage has wrong type
2203 107 common/cmd_bootm.c Kernel subimage type OK
2204 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2205 108 common/cmd_bootm.c Got kernel subimage data/size
2206 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2207 -109 common/cmd_bootm.c Can't get kernel subimage type
2208 -110 common/cmd_bootm.c Can't get kernel subimage comp
2209 -111 common/cmd_bootm.c Can't get kernel subimage os
2210 -112 common/cmd_bootm.c Can't get kernel subimage load address
2211 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2213 120 common/image.c Start initial ramdisk verification
2214 -120 common/image.c Ramdisk FIT image has incorrect format
2215 121 common/image.c Ramdisk FIT image has correct format
2216 122 common/image.c No ramdisk subimage unit name, using configuration
2217 -122 common/image.c Can't get configuration for ramdisk subimage
2218 123 common/image.c Ramdisk unit name specified
2219 -124 common/image.c Can't get ramdisk subimage node offset
2220 125 common/image.c Got ramdisk subimage node offset
2221 -125 common/image.c Ramdisk subimage hash verification failed
2222 126 common/image.c Ramdisk subimage hash verification OK
2223 -126 common/image.c Ramdisk subimage for unsupported architecture
2224 127 common/image.c Architecture check OK
2225 -127 common/image.c Can't get ramdisk subimage data/size
2226 128 common/image.c Got ramdisk subimage data/size
2227 129 common/image.c Can't get ramdisk load address
2228 -129 common/image.c Got ramdisk load address
2230 -130 common/cmd_doc.c Incorrect FIT image format
2231 131 common/cmd_doc.c FIT image format OK
2233 -140 common/cmd_ide.c Incorrect FIT image format
2234 141 common/cmd_ide.c FIT image format OK
2236 -150 common/cmd_nand.c Incorrect FIT image format
2237 151 common/cmd_nand.c FIT image format OK
2239 - Automatic software updates via TFTP server
2241 CONFIG_UPDATE_TFTP_CNT_MAX
2242 CONFIG_UPDATE_TFTP_MSEC_MAX
2244 These options enable and control the auto-update feature;
2245 for a more detailed description refer to doc/README.update.
2247 - MTD Support (mtdparts command, UBI support)
2250 Adds the MTD device infrastructure from the Linux kernel.
2251 Needed for mtdparts command support.
2253 CONFIG_MTD_PARTITIONS
2255 Adds the MTD partitioning infrastructure from the Linux
2256 kernel. Needed for UBI support.
2260 Enable building of SPL globally.
2262 CONFIG_SPL_TEXT_BASE
2263 TEXT_BASE for linking the SPL binary.
2266 LDSCRIPT for linking the SPL binary.
2268 CONFIG_SPL_LIBCOMMON_SUPPORT
2269 Support for common/libcommon.o in SPL binary
2271 CONFIG_SPL_LIBDISK_SUPPORT
2272 Support for disk/libdisk.o in SPL binary
2274 CONFIG_SPL_I2C_SUPPORT
2275 Support for drivers/i2c/libi2c.o in SPL binary
2277 CONFIG_SPL_GPIO_SUPPORT
2278 Support for drivers/gpio/libgpio.o in SPL binary
2280 CONFIG_SPL_MMC_SUPPORT
2281 Support for drivers/mmc/libmmc.o in SPL binary
2283 CONFIG_SPL_SERIAL_SUPPORT
2284 Support for drivers/serial/libserial.o in SPL binary
2286 CONFIG_SPL_SPI_FLASH_SUPPORT
2287 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2289 CONFIG_SPL_SPI_SUPPORT
2290 Support for drivers/spi/libspi.o in SPL binary
2292 CONFIG_SPL_FAT_SUPPORT
2293 Support for fs/fat/libfat.o in SPL binary
2295 CONFIG_SPL_LIBGENERIC_SUPPORT
2296 Support for lib/libgeneric.o in SPL binary
2301 [so far only for SMDK2400 boards]
2303 - Modem support enable:
2304 CONFIG_MODEM_SUPPORT
2306 - RTS/CTS Flow control enable:
2309 - Modem debug support:
2310 CONFIG_MODEM_SUPPORT_DEBUG
2312 Enables debugging stuff (char screen[1024], dbg())
2313 for modem support. Useful only with BDI2000.
2315 - Interrupt support (PPC):
2317 There are common interrupt_init() and timer_interrupt()
2318 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2319 for CPU specific initialization. interrupt_init_cpu()
2320 should set decrementer_count to appropriate value. If
2321 CPU resets decrementer automatically after interrupt
2322 (ppc4xx) it should set decrementer_count to zero.
2323 timer_interrupt() calls timer_interrupt_cpu() for CPU
2324 specific handling. If board has watchdog / status_led
2325 / other_activity_monitor it works automatically from
2326 general timer_interrupt().
2330 In the target system modem support is enabled when a
2331 specific key (key combination) is pressed during
2332 power-on. Otherwise U-Boot will boot normally
2333 (autoboot). The key_pressed() function is called from
2334 board_init(). Currently key_pressed() is a dummy
2335 function, returning 1 and thus enabling modem
2338 If there are no modem init strings in the
2339 environment, U-Boot proceed to autoboot; the
2340 previous output (banner, info printfs) will be
2343 See also: doc/README.Modem
2346 Configuration Settings:
2347 -----------------------
2349 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2350 undefine this when you're short of memory.
2352 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2353 width of the commands listed in the 'help' command output.
2355 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2356 prompt for user input.
2358 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2360 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2362 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2364 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2365 the application (usually a Linux kernel) when it is
2368 - CONFIG_SYS_BAUDRATE_TABLE:
2369 List of legal baudrate settings for this board.
2371 - CONFIG_SYS_CONSOLE_INFO_QUIET
2372 Suppress display of console information at boot.
2374 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2375 If the board specific function
2376 extern int overwrite_console (void);
2377 returns 1, the stdin, stderr and stdout are switched to the
2378 serial port, else the settings in the environment are used.
2380 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2381 Enable the call to overwrite_console().
2383 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2384 Enable overwrite of previous console environment settings.
2386 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2387 Begin and End addresses of the area used by the
2390 - CONFIG_SYS_ALT_MEMTEST:
2391 Enable an alternate, more extensive memory test.
2393 - CONFIG_SYS_MEMTEST_SCRATCH:
2394 Scratch address used by the alternate memory test
2395 You only need to set this if address zero isn't writeable
2397 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2398 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2399 this specified memory area will get subtracted from the top
2400 (end) of RAM and won't get "touched" at all by U-Boot. By
2401 fixing up gd->ram_size the Linux kernel should gets passed
2402 the now "corrected" memory size and won't touch it either.
2403 This should work for arch/ppc and arch/powerpc. Only Linux
2404 board ports in arch/powerpc with bootwrapper support that
2405 recalculate the memory size from the SDRAM controller setup
2406 will have to get fixed in Linux additionally.
2408 This option can be used as a workaround for the 440EPx/GRx
2409 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2412 WARNING: Please make sure that this value is a multiple of
2413 the Linux page size (normally 4k). If this is not the case,
2414 then the end address of the Linux memory will be located at a
2415 non page size aligned address and this could cause major
2418 - CONFIG_SYS_TFTP_LOADADDR:
2419 Default load address for network file downloads
2421 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2422 Enable temporary baudrate change while serial download
2424 - CONFIG_SYS_SDRAM_BASE:
2425 Physical start address of SDRAM. _Must_ be 0 here.
2427 - CONFIG_SYS_MBIO_BASE:
2428 Physical start address of Motherboard I/O (if using a
2431 - CONFIG_SYS_FLASH_BASE:
2432 Physical start address of Flash memory.
2434 - CONFIG_SYS_MONITOR_BASE:
2435 Physical start address of boot monitor code (set by
2436 make config files to be same as the text base address
2437 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2438 CONFIG_SYS_FLASH_BASE when booting from flash.
2440 - CONFIG_SYS_MONITOR_LEN:
2441 Size of memory reserved for monitor code, used to
2442 determine _at_compile_time_ (!) if the environment is
2443 embedded within the U-Boot image, or in a separate
2446 - CONFIG_SYS_MALLOC_LEN:
2447 Size of DRAM reserved for malloc() use.
2449 - CONFIG_SYS_BOOTM_LEN:
2450 Normally compressed uImages are limited to an
2451 uncompressed size of 8 MBytes. If this is not enough,
2452 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2453 to adjust this setting to your needs.
2455 - CONFIG_SYS_BOOTMAPSZ:
2456 Maximum size of memory mapped by the startup code of
2457 the Linux kernel; all data that must be processed by
2458 the Linux kernel (bd_info, boot arguments, FDT blob if
2459 used) must be put below this limit, unless "bootm_low"
2460 enviroment variable is defined and non-zero. In such case
2461 all data for the Linux kernel must be between "bootm_low"
2462 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2463 variable "bootm_mapsize" will override the value of
2464 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2465 then the value in "bootm_size" will be used instead.
2467 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2468 Enable initrd_high functionality. If defined then the
2469 initrd_high feature is enabled and the bootm ramdisk subcommand
2472 - CONFIG_SYS_BOOT_GET_CMDLINE:
2473 Enables allocating and saving kernel cmdline in space between
2474 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2476 - CONFIG_SYS_BOOT_GET_KBD:
2477 Enables allocating and saving a kernel copy of the bd_info in
2478 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2480 - CONFIG_SYS_MAX_FLASH_BANKS:
2481 Max number of Flash memory banks
2483 - CONFIG_SYS_MAX_FLASH_SECT:
2484 Max number of sectors on a Flash chip
2486 - CONFIG_SYS_FLASH_ERASE_TOUT:
2487 Timeout for Flash erase operations (in ms)
2489 - CONFIG_SYS_FLASH_WRITE_TOUT:
2490 Timeout for Flash write operations (in ms)
2492 - CONFIG_SYS_FLASH_LOCK_TOUT
2493 Timeout for Flash set sector lock bit operation (in ms)
2495 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2496 Timeout for Flash clear lock bits operation (in ms)
2498 - CONFIG_SYS_FLASH_PROTECTION
2499 If defined, hardware flash sectors protection is used
2500 instead of U-Boot software protection.
2502 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2504 Enable TFTP transfers directly to flash memory;
2505 without this option such a download has to be
2506 performed in two steps: (1) download to RAM, and (2)
2507 copy from RAM to flash.
2509 The two-step approach is usually more reliable, since
2510 you can check if the download worked before you erase
2511 the flash, but in some situations (when system RAM is
2512 too limited to allow for a temporary copy of the
2513 downloaded image) this option may be very useful.
2515 - CONFIG_SYS_FLASH_CFI:
2516 Define if the flash driver uses extra elements in the
2517 common flash structure for storing flash geometry.
2519 - CONFIG_FLASH_CFI_DRIVER
2520 This option also enables the building of the cfi_flash driver
2521 in the drivers directory
2523 - CONFIG_FLASH_CFI_MTD
2524 This option enables the building of the cfi_mtd driver
2525 in the drivers directory. The driver exports CFI flash
2528 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2529 Use buffered writes to flash.
2531 - CONFIG_FLASH_SPANSION_S29WS_N
2532 s29ws-n MirrorBit flash has non-standard addresses for buffered
2535 - CONFIG_SYS_FLASH_QUIET_TEST
2536 If this option is defined, the common CFI flash doesn't
2537 print it's warning upon not recognized FLASH banks. This
2538 is useful, if some of the configured banks are only
2539 optionally available.
2541 - CONFIG_FLASH_SHOW_PROGRESS
2542 If defined (must be an integer), print out countdown
2543 digits and dots. Recommended value: 45 (9..1) for 80
2544 column displays, 15 (3..1) for 40 column displays.
2546 - CONFIG_SYS_RX_ETH_BUFFER:
2547 Defines the number of Ethernet receive buffers. On some
2548 Ethernet controllers it is recommended to set this value
2549 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2550 buffers can be full shortly after enabling the interface
2551 on high Ethernet traffic.
2552 Defaults to 4 if not defined.
2554 - CONFIG_ENV_MAX_ENTRIES
2556 Maximum number of entries in the hash table that is used
2557 internally to store the environment settings. The default
2558 setting is supposed to be generous and should work in most
2559 cases. This setting can be used to tune behaviour; see
2560 lib/hashtable.c for details.
2562 The following definitions that deal with the placement and management
2563 of environment data (variable area); in general, we support the
2564 following configurations:
2566 - CONFIG_BUILD_ENVCRC:
2568 Builds up envcrc with the target environment so that external utils
2569 may easily extract it and embed it in final U-Boot images.
2571 - CONFIG_ENV_IS_IN_FLASH:
2573 Define this if the environment is in flash memory.
2575 a) The environment occupies one whole flash sector, which is
2576 "embedded" in the text segment with the U-Boot code. This
2577 happens usually with "bottom boot sector" or "top boot
2578 sector" type flash chips, which have several smaller
2579 sectors at the start or the end. For instance, such a
2580 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2581 such a case you would place the environment in one of the
2582 4 kB sectors - with U-Boot code before and after it. With
2583 "top boot sector" type flash chips, you would put the
2584 environment in one of the last sectors, leaving a gap
2585 between U-Boot and the environment.
2587 - CONFIG_ENV_OFFSET:
2589 Offset of environment data (variable area) to the
2590 beginning of flash memory; for instance, with bottom boot
2591 type flash chips the second sector can be used: the offset
2592 for this sector is given here.
2594 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2598 This is just another way to specify the start address of
2599 the flash sector containing the environment (instead of
2602 - CONFIG_ENV_SECT_SIZE:
2604 Size of the sector containing the environment.
2607 b) Sometimes flash chips have few, equal sized, BIG sectors.
2608 In such a case you don't want to spend a whole sector for
2613 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2614 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2615 of this flash sector for the environment. This saves
2616 memory for the RAM copy of the environment.
2618 It may also save flash memory if you decide to use this
2619 when your environment is "embedded" within U-Boot code,
2620 since then the remainder of the flash sector could be used
2621 for U-Boot code. It should be pointed out that this is
2622 STRONGLY DISCOURAGED from a robustness point of view:
2623 updating the environment in flash makes it always
2624 necessary to erase the WHOLE sector. If something goes
2625 wrong before the contents has been restored from a copy in
2626 RAM, your target system will be dead.
2628 - CONFIG_ENV_ADDR_REDUND
2629 CONFIG_ENV_SIZE_REDUND
2631 These settings describe a second storage area used to hold
2632 a redundant copy of the environment data, so that there is
2633 a valid backup copy in case there is a power failure during
2634 a "saveenv" operation.
2636 BE CAREFUL! Any changes to the flash layout, and some changes to the
2637 source code will make it necessary to adapt <board>/u-boot.lds*
2641 - CONFIG_ENV_IS_IN_NVRAM:
2643 Define this if you have some non-volatile memory device
2644 (NVRAM, battery buffered SRAM) which you want to use for the
2650 These two #defines are used to determine the memory area you
2651 want to use for environment. It is assumed that this memory
2652 can just be read and written to, without any special
2655 BE CAREFUL! The first access to the environment happens quite early
2656 in U-Boot initalization (when we try to get the setting of for the
2657 console baudrate). You *MUST* have mapped your NVRAM area then, or
2660 Please note that even with NVRAM we still use a copy of the
2661 environment in RAM: we could work on NVRAM directly, but we want to
2662 keep settings there always unmodified except somebody uses "saveenv"
2663 to save the current settings.
2666 - CONFIG_ENV_IS_IN_EEPROM:
2668 Use this if you have an EEPROM or similar serial access
2669 device and a driver for it.
2671 - CONFIG_ENV_OFFSET:
2674 These two #defines specify the offset and size of the
2675 environment area within the total memory of your EEPROM.
2677 - CONFIG_SYS_I2C_EEPROM_ADDR:
2678 If defined, specified the chip address of the EEPROM device.
2679 The default address is zero.
2681 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2682 If defined, the number of bits used to address bytes in a
2683 single page in the EEPROM device. A 64 byte page, for example
2684 would require six bits.
2686 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2687 If defined, the number of milliseconds to delay between
2688 page writes. The default is zero milliseconds.
2690 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2691 The length in bytes of the EEPROM memory array address. Note
2692 that this is NOT the chip address length!
2694 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2695 EEPROM chips that implement "address overflow" are ones
2696 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2697 address and the extra bits end up in the "chip address" bit
2698 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2701 Note that we consider the length of the address field to
2702 still be one byte because the extra address bits are hidden
2703 in the chip address.
2705 - CONFIG_SYS_EEPROM_SIZE:
2706 The size in bytes of the EEPROM device.
2708 - CONFIG_ENV_EEPROM_IS_ON_I2C
2709 define this, if you have I2C and SPI activated, and your
2710 EEPROM, which holds the environment, is on the I2C bus.
2712 - CONFIG_I2C_ENV_EEPROM_BUS
2713 if you have an Environment on an EEPROM reached over
2714 I2C muxes, you can define here, how to reach this
2715 EEPROM. For example:
2717 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2719 EEPROM which holds the environment, is reached over
2720 a pca9547 i2c mux with address 0x70, channel 3.
2722 - CONFIG_ENV_IS_IN_DATAFLASH:
2724 Define this if you have a DataFlash memory device which you
2725 want to use for the environment.
2727 - CONFIG_ENV_OFFSET:
2731 These three #defines specify the offset and size of the
2732 environment area within the total memory of your DataFlash placed
2733 at the specified address.
2735 - CONFIG_ENV_IS_IN_NAND:
2737 Define this if you have a NAND device which you want to use
2738 for the environment.
2740 - CONFIG_ENV_OFFSET:
2743 These two #defines specify the offset and size of the environment
2744 area within the first NAND device. CONFIG_ENV_OFFSET must be
2745 aligned to an erase block boundary.
2747 - CONFIG_ENV_OFFSET_REDUND (optional):
2749 This setting describes a second storage area of CONFIG_ENV_SIZE
2750 size used to hold a redundant copy of the environment data, so
2751 that there is a valid backup copy in case there is a power failure
2752 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2753 aligned to an erase block boundary.
2755 - CONFIG_ENV_RANGE (optional):
2757 Specifies the length of the region in which the environment
2758 can be written. This should be a multiple of the NAND device's
2759 block size. Specifying a range with more erase blocks than
2760 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2761 the range to be avoided.
2763 - CONFIG_ENV_OFFSET_OOB (optional):
2765 Enables support for dynamically retrieving the offset of the
2766 environment from block zero's out-of-band data. The
2767 "nand env.oob" command can be used to record this offset.
2768 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2769 using CONFIG_ENV_OFFSET_OOB.
2771 - CONFIG_NAND_ENV_DST
2773 Defines address in RAM to which the nand_spl code should copy the
2774 environment. If redundant environment is used, it will be copied to
2775 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2777 - CONFIG_SYS_SPI_INIT_OFFSET
2779 Defines offset to the initial SPI buffer area in DPRAM. The
2780 area is used at an early stage (ROM part) if the environment
2781 is configured to reside in the SPI EEPROM: We need a 520 byte
2782 scratch DPRAM area. It is used between the two initialization
2783 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2784 to be a good choice since it makes it far enough from the
2785 start of the data area as well as from the stack pointer.
2787 Please note that the environment is read-only until the monitor
2788 has been relocated to RAM and a RAM copy of the environment has been
2789 created; also, when using EEPROM you will have to use getenv_f()
2790 until then to read environment variables.
2792 The environment is protected by a CRC32 checksum. Before the monitor
2793 is relocated into RAM, as a result of a bad CRC you will be working
2794 with the compiled-in default environment - *silently*!!! [This is
2795 necessary, because the first environment variable we need is the
2796 "baudrate" setting for the console - if we have a bad CRC, we don't
2797 have any device yet where we could complain.]
2799 Note: once the monitor has been relocated, then it will complain if
2800 the default environment is used; a new CRC is computed as soon as you
2801 use the "saveenv" command to store a valid environment.
2803 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2804 Echo the inverted Ethernet link state to the fault LED.
2806 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2807 also needs to be defined.
2809 - CONFIG_SYS_FAULT_MII_ADDR:
2810 MII address of the PHY to check for the Ethernet link state.
2812 - CONFIG_NS16550_MIN_FUNCTIONS:
2813 Define this if you desire to only have use of the NS16550_init
2814 and NS16550_putc functions for the serial driver located at
2815 drivers/serial/ns16550.c. This option is useful for saving
2816 space for already greatly restricted images, including but not
2817 limited to NAND_SPL configurations.
2819 Low Level (hardware related) configuration options:
2820 ---------------------------------------------------
2822 - CONFIG_SYS_CACHELINE_SIZE:
2823 Cache Line Size of the CPU.
2825 - CONFIG_SYS_DEFAULT_IMMR:
2826 Default address of the IMMR after system reset.
2828 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2829 and RPXsuper) to be able to adjust the position of
2830 the IMMR register after a reset.
2832 - Floppy Disk Support:
2833 CONFIG_SYS_FDC_DRIVE_NUMBER
2835 the default drive number (default value 0)
2837 CONFIG_SYS_ISA_IO_STRIDE
2839 defines the spacing between FDC chipset registers
2842 CONFIG_SYS_ISA_IO_OFFSET
2844 defines the offset of register from address. It
2845 depends on which part of the data bus is connected to
2846 the FDC chipset. (default value 0)
2848 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2849 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2852 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2853 fdc_hw_init() is called at the beginning of the FDC
2854 setup. fdc_hw_init() must be provided by the board
2855 source code. It is used to make hardware dependant
2859 Most IDE controllers were designed to be connected with PCI
2860 interface. Only few of them were designed for AHB interface.
2861 When software is doing ATA command and data transfer to
2862 IDE devices through IDE-AHB controller, some additional
2863 registers accessing to these kind of IDE-AHB controller
2866 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2867 DO NOT CHANGE unless you know exactly what you're
2868 doing! (11-4) [MPC8xx/82xx systems only]
2870 - CONFIG_SYS_INIT_RAM_ADDR:
2872 Start address of memory area that can be used for
2873 initial data and stack; please note that this must be
2874 writable memory that is working WITHOUT special
2875 initialization, i. e. you CANNOT use normal RAM which
2876 will become available only after programming the
2877 memory controller and running certain initialization
2880 U-Boot uses the following memory types:
2881 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2882 - MPC824X: data cache
2883 - PPC4xx: data cache
2885 - CONFIG_SYS_GBL_DATA_OFFSET:
2887 Offset of the initial data structure in the memory
2888 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2889 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2890 data is located at the end of the available space
2891 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2892 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2893 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2894 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2897 On the MPC824X (or other systems that use the data
2898 cache for initial memory) the address chosen for
2899 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2900 point to an otherwise UNUSED address space between
2901 the top of RAM and the start of the PCI space.
2903 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2905 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2907 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2909 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2911 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2913 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2915 - CONFIG_SYS_OR_TIMING_SDRAM:
2918 - CONFIG_SYS_MAMR_PTA:
2919 periodic timer for refresh
2921 - CONFIG_SYS_DER: Debug Event Register (37-47)
2923 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2924 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2925 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2926 CONFIG_SYS_BR1_PRELIM:
2927 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2929 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2930 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2931 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2932 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2934 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2935 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2936 Machine Mode Register and Memory Periodic Timer
2937 Prescaler definitions (SDRAM timing)
2939 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2940 enable I2C microcode relocation patch (MPC8xx);
2941 define relocation offset in DPRAM [DSP2]
2943 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2944 enable SMC microcode relocation patch (MPC8xx);
2945 define relocation offset in DPRAM [SMC1]
2947 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2948 enable SPI microcode relocation patch (MPC8xx);
2949 define relocation offset in DPRAM [SCC4]
2951 - CONFIG_SYS_USE_OSCCLK:
2952 Use OSCM clock mode on MBX8xx board. Be careful,
2953 wrong setting might damage your board. Read
2954 doc/README.MBX before setting this variable!
2956 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2957 Offset of the bootmode word in DPRAM used by post
2958 (Power On Self Tests). This definition overrides
2959 #define'd default value in commproc.h resp.
2962 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2963 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2964 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2965 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2966 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2967 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2968 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2969 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2970 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2972 - CONFIG_PCI_DISABLE_PCIE:
2973 Disable PCI-Express on systems where it is supported but not
2977 Chip has SRIO or not
2980 Board has SRIO 1 port available
2983 Board has SRIO 2 port available
2985 - CONFIG_SYS_SRIOn_MEM_VIRT:
2986 Virtual Address of SRIO port 'n' memory region
2988 - CONFIG_SYS_SRIOn_MEM_PHYS:
2989 Physical Address of SRIO port 'n' memory region
2991 - CONFIG_SYS_SRIOn_MEM_SIZE:
2992 Size of SRIO port 'n' memory region
2994 - CONFIG_SYS_NDFC_16
2995 Defined to tell the NDFC that the NAND chip is using a
2998 - CONFIG_SYS_NDFC_EBC0_CFG
2999 Sets the EBC0_CFG register for the NDFC. If not defined
3000 a default value will be used.
3003 Get DDR timing information from an I2C EEPROM. Common
3004 with pluggable memory modules such as SODIMMs
3007 I2C address of the SPD EEPROM
3009 - CONFIG_SYS_SPD_BUS_NUM
3010 If SPD EEPROM is on an I2C bus other than the first
3011 one, specify here. Note that the value must resolve
3012 to something your driver can deal with.
3014 - CONFIG_SYS_DDR_RAW_TIMING
3015 Get DDR timing information from other than SPD. Common with
3016 soldered DDR chips onboard without SPD. DDR raw timing
3017 parameters are extracted from datasheet and hard-coded into
3018 header files or board specific files.
3020 - CONFIG_SYS_83XX_DDR_USES_CS0
3021 Only for 83xx systems. If specified, then DDR should
3022 be configured using CS0 and CS1 instead of CS2 and CS3.
3024 - CONFIG_ETHER_ON_FEC[12]
3025 Define to enable FEC[12] on a 8xx series processor.
3027 - CONFIG_FEC[12]_PHY
3028 Define to the hardcoded PHY address which corresponds
3029 to the given FEC; i. e.
3030 #define CONFIG_FEC1_PHY 4
3031 means that the PHY with address 4 is connected to FEC1
3033 When set to -1, means to probe for first available.
3035 - CONFIG_FEC[12]_PHY_NORXERR
3036 The PHY does not have a RXERR line (RMII only).
3037 (so program the FEC to ignore it).
3040 Enable RMII mode for all FECs.
3041 Note that this is a global option, we can't
3042 have one FEC in standard MII mode and another in RMII mode.
3044 - CONFIG_CRC32_VERIFY
3045 Add a verify option to the crc32 command.
3048 => crc32 -v <address> <count> <crc32>
3050 Where address/count indicate a memory area
3051 and crc32 is the correct crc32 which the
3055 Add the "loopw" memory command. This only takes effect if
3056 the memory commands are activated globally (CONFIG_CMD_MEM).
3059 Add the "mdc" and "mwc" memory commands. These are cyclic
3064 This command will print 4 bytes (10,11,12,13) each 500 ms.
3066 => mwc.l 100 12345678 10
3067 This command will write 12345678 to address 100 all 10 ms.
3069 This only takes effect if the memory commands are activated
3070 globally (CONFIG_CMD_MEM).
3072 - CONFIG_SKIP_LOWLEVEL_INIT
3073 [ARM only] If this variable is defined, then certain
3074 low level initializations (like setting up the memory
3075 controller) are omitted and/or U-Boot does not
3076 relocate itself into RAM.
3078 Normally this variable MUST NOT be defined. The only
3079 exception is when U-Boot is loaded (to RAM) by some
3080 other boot loader or by a debugger which performs
3081 these initializations itself.
3084 Modifies the behaviour of start.S when compiling a loader
3085 that is executed before the actual U-Boot. E.g. when
3086 compiling a NAND SPL.
3088 - CONFIG_USE_ARCH_MEMCPY
3089 CONFIG_USE_ARCH_MEMSET
3090 If these options are used a optimized version of memcpy/memset will
3091 be used if available. These functions may be faster under some
3092 conditions but may increase the binary size.
3094 Building the Software:
3095 ======================
3097 Building U-Boot has been tested in several native build environments
3098 and in many different cross environments. Of course we cannot support
3099 all possibly existing versions of cross development tools in all
3100 (potentially obsolete) versions. In case of tool chain problems we
3101 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3102 which is extensively used to build and test U-Boot.
3104 If you are not using a native environment, it is assumed that you
3105 have GNU cross compiling tools available in your path. In this case,
3106 you must set the environment variable CROSS_COMPILE in your shell.
3107 Note that no changes to the Makefile or any other source files are
3108 necessary. For example using the ELDK on a 4xx CPU, please enter:
3110 $ CROSS_COMPILE=ppc_4xx-
3111 $ export CROSS_COMPILE
3113 Note: If you wish to generate Windows versions of the utilities in
3114 the tools directory you can use the MinGW toolchain
3115 (http://www.mingw.org). Set your HOST tools to the MinGW
3116 toolchain and execute 'make tools'. For example:
3118 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3120 Binaries such as tools/mkimage.exe will be created which can
3121 be executed on computers running Windows.
3123 U-Boot is intended to be simple to build. After installing the
3124 sources you must configure U-Boot for one specific board type. This
3129 where "NAME_config" is the name of one of the existing configu-
3130 rations; see the main Makefile for supported names.
3132 Note: for some board special configuration names may exist; check if
3133 additional information is available from the board vendor; for
3134 instance, the TQM823L systems are available without (standard)
3135 or with LCD support. You can select such additional "features"
3136 when choosing the configuration, i. e.
3139 - will configure for a plain TQM823L, i. e. no LCD support
3141 make TQM823L_LCD_config
3142 - will configure for a TQM823L with U-Boot console on LCD
3147 Finally, type "make all", and you should get some working U-Boot
3148 images ready for download to / installation on your system:
3150 - "u-boot.bin" is a raw binary image
3151 - "u-boot" is an image in ELF binary format
3152 - "u-boot.srec" is in Motorola S-Record format
3154 By default the build is performed locally and the objects are saved
3155 in the source directory. One of the two methods can be used to change
3156 this behavior and build U-Boot to some external directory:
3158 1. Add O= to the make command line invocations:
3160 make O=/tmp/build distclean
3161 make O=/tmp/build NAME_config
3162 make O=/tmp/build all
3164 2. Set environment variable BUILD_DIR to point to the desired location:
3166 export BUILD_DIR=/tmp/build
3171 Note that the command line "O=" setting overrides the BUILD_DIR environment
3175 Please be aware that the Makefiles assume you are using GNU make, so
3176 for instance on NetBSD you might need to use "gmake" instead of
3180 If the system board that you have is not listed, then you will need
3181 to port U-Boot to your hardware platform. To do this, follow these
3184 1. Add a new configuration option for your board to the toplevel
3185 "Makefile" and to the "MAKEALL" script, using the existing
3186 entries as examples. Note that here and at many other places
3187 boards and other names are listed in alphabetical sort order. Please
3189 2. Create a new directory to hold your board specific code. Add any
3190 files you need. In your board directory, you will need at least
3191 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3192 3. Create a new configuration file "include/configs/<board>.h" for
3194 3. If you're porting U-Boot to a new CPU, then also create a new
3195 directory to hold your CPU specific code. Add any files you need.
3196 4. Run "make <board>_config" with your new name.
3197 5. Type "make", and you should get a working "u-boot.srec" file
3198 to be installed on your target system.
3199 6. Debug and solve any problems that might arise.
3200 [Of course, this last step is much harder than it sounds.]
3203 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3204 ==============================================================
3206 If you have modified U-Boot sources (for instance added a new board
3207 or support for new devices, a new CPU, etc.) you are expected to
3208 provide feedback to the other developers. The feedback normally takes
3209 the form of a "patch", i. e. a context diff against a certain (latest
3210 official or latest in the git repository) version of U-Boot sources.
3212 But before you submit such a patch, please verify that your modifi-
3213 cation did not break existing code. At least make sure that *ALL* of
3214 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3215 just run the "MAKEALL" script, which will configure and build U-Boot
3216 for ALL supported system. Be warned, this will take a while. You can
3217 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3218 environment variable to the script, i. e. to use the ELDK cross tools
3221 CROSS_COMPILE=ppc_8xx- MAKEALL
3223 or to build on a native PowerPC system you can type
3225 CROSS_COMPILE=' ' MAKEALL
3227 When using the MAKEALL script, the default behaviour is to build
3228 U-Boot in the source directory. This location can be changed by
3229 setting the BUILD_DIR environment variable. Also, for each target
3230 built, the MAKEALL script saves two log files (<target>.ERR and
3231 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3232 location can be changed by setting the MAKEALL_LOGDIR environment
3233 variable. For example:
3235 export BUILD_DIR=/tmp/build
3236 export MAKEALL_LOGDIR=/tmp/log
3237 CROSS_COMPILE=ppc_8xx- MAKEALL
3239 With the above settings build objects are saved in the /tmp/build,
3240 log files are saved in the /tmp/log and the source tree remains clean
3241 during the whole build process.
3244 See also "U-Boot Porting Guide" below.
3247 Monitor Commands - Overview:
3248 ============================
3250 go - start application at address 'addr'
3251 run - run commands in an environment variable
3252 bootm - boot application image from memory
3253 bootp - boot image via network using BootP/TFTP protocol
3254 tftpboot- boot image via network using TFTP protocol
3255 and env variables "ipaddr" and "serverip"
3256 (and eventually "gatewayip")
3257 rarpboot- boot image via network using RARP/TFTP protocol
3258 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3259 loads - load S-Record file over serial line
3260 loadb - load binary file over serial line (kermit mode)
3262 mm - memory modify (auto-incrementing)
3263 nm - memory modify (constant address)
3264 mw - memory write (fill)
3266 cmp - memory compare
3267 crc32 - checksum calculation
3268 i2c - I2C sub-system
3269 sspi - SPI utility commands
3270 base - print or set address offset
3271 printenv- print environment variables
3272 setenv - set environment variables
3273 saveenv - save environment variables to persistent storage
3274 protect - enable or disable FLASH write protection
3275 erase - erase FLASH memory
3276 flinfo - print FLASH memory information
3277 bdinfo - print Board Info structure
3278 iminfo - print header information for application image
3279 coninfo - print console devices and informations
3280 ide - IDE sub-system
3281 loop - infinite loop on address range
3282 loopw - infinite write loop on address range
3283 mtest - simple RAM test
3284 icache - enable or disable instruction cache
3285 dcache - enable or disable data cache
3286 reset - Perform RESET of the CPU
3287 echo - echo args to console
3288 version - print monitor version
3289 help - print online help
3290 ? - alias for 'help'
3293 Monitor Commands - Detailed Description:
3294 ========================================
3298 For now: just type "help <command>".
3301 Environment Variables:
3302 ======================
3304 U-Boot supports user configuration using Environment Variables which
3305 can be made persistent by saving to Flash memory.
3307 Environment Variables are set using "setenv", printed using
3308 "printenv", and saved to Flash using "saveenv". Using "setenv"
3309 without a value can be used to delete a variable from the
3310 environment. As long as you don't save the environment you are
3311 working with an in-memory copy. In case the Flash area containing the
3312 environment is erased by accident, a default environment is provided.
3314 Some configuration options can be set using Environment Variables.
3316 List of environment variables (most likely not complete):
3318 baudrate - see CONFIG_BAUDRATE
3320 bootdelay - see CONFIG_BOOTDELAY
3322 bootcmd - see CONFIG_BOOTCOMMAND
3324 bootargs - Boot arguments when booting an RTOS image
3326 bootfile - Name of the image to load with TFTP
3328 bootm_low - Memory range available for image processing in the bootm
3329 command can be restricted. This variable is given as
3330 a hexadecimal number and defines lowest address allowed
3331 for use by the bootm command. See also "bootm_size"
3332 environment variable. Address defined by "bootm_low" is
3333 also the base of the initial memory mapping for the Linux
3334 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3337 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3338 This variable is given as a hexadecimal number and it
3339 defines the size of the memory region starting at base
3340 address bootm_low that is accessible by the Linux kernel
3341 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3342 as the default value if it is defined, and bootm_size is
3345 bootm_size - Memory range available for image processing in the bootm
3346 command can be restricted. This variable is given as
3347 a hexadecimal number and defines the size of the region
3348 allowed for use by the bootm command. See also "bootm_low"
3349 environment variable.
3351 updatefile - Location of the software update file on a TFTP server, used
3352 by the automatic software update feature. Please refer to
3353 documentation in doc/README.update for more details.
3355 autoload - if set to "no" (any string beginning with 'n'),
3356 "bootp" will just load perform a lookup of the
3357 configuration from the BOOTP server, but not try to
3358 load any image using TFTP
3360 autostart - if set to "yes", an image loaded using the "bootp",
3361 "rarpboot", "tftpboot" or "diskboot" commands will
3362 be automatically started (by internally calling
3365 If set to "no", a standalone image passed to the
3366 "bootm" command will be copied to the load address
3367 (and eventually uncompressed), but NOT be started.
3368 This can be used to load and uncompress arbitrary
3371 fdt_high - if set this restricts the maximum address that the
3372 flattened device tree will be copied into upon boot.
3373 If this is set to the special value 0xFFFFFFFF then
3374 the fdt will not be copied at all on boot. For this
3375 to work it must reside in writable memory, have
3376 sufficient padding on the end of it for u-boot to
3377 add the information it needs into it, and the memory
3378 must be accessible by the kernel.
3380 i2cfast - (PPC405GP|PPC405EP only)
3381 if set to 'y' configures Linux I2C driver for fast
3382 mode (400kHZ). This environment variable is used in
3383 initialization code. So, for changes to be effective
3384 it must be saved and board must be reset.
3386 initrd_high - restrict positioning of initrd images:
3387 If this variable is not set, initrd images will be
3388 copied to the highest possible address in RAM; this
3389 is usually what you want since it allows for
3390 maximum initrd size. If for some reason you want to
3391 make sure that the initrd image is loaded below the
3392 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3393 variable to a value of "no" or "off" or "0".
3394 Alternatively, you can set it to a maximum upper
3395 address to use (U-Boot will still check that it
3396 does not overwrite the U-Boot stack and data).
3398 For instance, when you have a system with 16 MB
3399 RAM, and want to reserve 4 MB from use by Linux,
3400 you can do this by adding "mem=12M" to the value of
3401 the "bootargs" variable. However, now you must make
3402 sure that the initrd image is placed in the first
3403 12 MB as well - this can be done with
3405 setenv initrd_high 00c00000
3407 If you set initrd_high to 0xFFFFFFFF, this is an
3408 indication to U-Boot that all addresses are legal
3409 for the Linux kernel, including addresses in flash
3410 memory. In this case U-Boot will NOT COPY the
3411 ramdisk at all. This may be useful to reduce the
3412 boot time on your system, but requires that this
3413 feature is supported by your Linux kernel.
3415 ipaddr - IP address; needed for tftpboot command
3417 loadaddr - Default load address for commands like "bootp",
3418 "rarpboot", "tftpboot", "loadb" or "diskboot"
3420 loads_echo - see CONFIG_LOADS_ECHO
3422 serverip - TFTP server IP address; needed for tftpboot command
3424 bootretry - see CONFIG_BOOT_RETRY_TIME
3426 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3428 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3430 ethprime - When CONFIG_NET_MULTI is enabled controls which
3431 interface is used first.
3433 ethact - When CONFIG_NET_MULTI is enabled controls which
3434 interface is currently active. For example you
3435 can do the following
3437 => setenv ethact FEC
3438 => ping 192.168.0.1 # traffic sent on FEC
3439 => setenv ethact SCC
3440 => ping 10.0.0.1 # traffic sent on SCC
3442 ethrotate - When set to "no" U-Boot does not go through all
3443 available network interfaces.
3444 It just stays at the currently selected interface.
3446 netretry - When set to "no" each network operation will
3447 either succeed or fail without retrying.
3448 When set to "once" the network operation will
3449 fail when all the available network interfaces
3450 are tried once without success.
3451 Useful on scripts which control the retry operation
3454 npe_ucode - set load address for the NPE microcode
3456 tftpsrcport - If this is set, the value is used for TFTP's
3459 tftpdstport - If this is set, the value is used for TFTP's UDP
3460 destination port instead of the Well Know Port 69.
3462 tftpblocksize - Block size to use for TFTP transfers; if not set,
3463 we use the TFTP server's default block size
3465 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3466 seconds, minimum value is 1000 = 1 second). Defines
3467 when a packet is considered to be lost so it has to
3468 be retransmitted. The default is 5000 = 5 seconds.
3469 Lowering this value may make downloads succeed
3470 faster in networks with high packet loss rates or
3471 with unreliable TFTP servers.
3473 vlan - When set to a value < 4095 the traffic over
3474 Ethernet is encapsulated/received over 802.1q
3477 The following environment variables may be used and automatically
3478 updated by the network boot commands ("bootp" and "rarpboot"),
3479 depending the information provided by your boot server:
3481 bootfile - see above
3482 dnsip - IP address of your Domain Name Server
3483 dnsip2 - IP address of your secondary Domain Name Server
3484 gatewayip - IP address of the Gateway (Router) to use
3485 hostname - Target hostname
3487 netmask - Subnet Mask
3488 rootpath - Pathname of the root filesystem on the NFS server
3489 serverip - see above
3492 There are two special Environment Variables:
3494 serial# - contains hardware identification information such
3495 as type string and/or serial number
3496 ethaddr - Ethernet address
3498 These variables can be set only once (usually during manufacturing of
3499 the board). U-Boot refuses to delete or overwrite these variables
3500 once they have been set once.
3503 Further special Environment Variables:
3505 ver - Contains the U-Boot version string as printed
3506 with the "version" command. This variable is
3507 readonly (see CONFIG_VERSION_VARIABLE).
3510 Please note that changes to some configuration parameters may take
3511 only effect after the next boot (yes, that's just like Windoze :-).
3514 Command Line Parsing:
3515 =====================
3517 There are two different command line parsers available with U-Boot:
3518 the old "simple" one, and the much more powerful "hush" shell:
3520 Old, simple command line parser:
3521 --------------------------------
3523 - supports environment variables (through setenv / saveenv commands)
3524 - several commands on one line, separated by ';'
3525 - variable substitution using "... ${name} ..." syntax
3526 - special characters ('$', ';') can be escaped by prefixing with '\',
3528 setenv bootcmd bootm \${address}
3529 - You can also escape text by enclosing in single apostrophes, for example:
3530 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3535 - similar to Bourne shell, with control structures like
3536 if...then...else...fi, for...do...done; while...do...done,
3537 until...do...done, ...
3538 - supports environment ("global") variables (through setenv / saveenv
3539 commands) and local shell variables (through standard shell syntax
3540 "name=value"); only environment variables can be used with "run"
3546 (1) If a command line (or an environment variable executed by a "run"
3547 command) contains several commands separated by semicolon, and
3548 one of these commands fails, then the remaining commands will be
3551 (2) If you execute several variables with one call to run (i. e.
3552 calling run with a list of variables as arguments), any failing
3553 command will cause "run" to terminate, i. e. the remaining
3554 variables are not executed.
3556 Note for Redundant Ethernet Interfaces:
3557 =======================================
3559 Some boards come with redundant Ethernet interfaces; U-Boot supports
3560 such configurations and is capable of automatic selection of a
3561 "working" interface when needed. MAC assignment works as follows:
3563 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3564 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3565 "eth1addr" (=>eth1), "eth2addr", ...
3567 If the network interface stores some valid MAC address (for instance
3568 in SROM), this is used as default address if there is NO correspon-
3569 ding setting in the environment; if the corresponding environment
3570 variable is set, this overrides the settings in the card; that means:
3572 o If the SROM has a valid MAC address, and there is no address in the
3573 environment, the SROM's address is used.
3575 o If there is no valid address in the SROM, and a definition in the
3576 environment exists, then the value from the environment variable is
3579 o If both the SROM and the environment contain a MAC address, and
3580 both addresses are the same, this MAC address is used.
3582 o If both the SROM and the environment contain a MAC address, and the
3583 addresses differ, the value from the environment is used and a
3586 o If neither SROM nor the environment contain a MAC address, an error
3589 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3590 will be programmed into hardware as part of the initialization process. This
3591 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3592 The naming convention is as follows:
3593 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3598 U-Boot is capable of booting (and performing other auxiliary operations on)
3599 images in two formats:
3601 New uImage format (FIT)
3602 -----------------------
3604 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3605 to Flattened Device Tree). It allows the use of images with multiple
3606 components (several kernels, ramdisks, etc.), with contents protected by
3607 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3613 Old image format is based on binary files which can be basically anything,
3614 preceded by a special header; see the definitions in include/image.h for
3615 details; basically, the header defines the following image properties:
3617 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3618 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3619 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3620 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3622 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3623 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3624 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3625 * Compression Type (uncompressed, gzip, bzip2)
3631 The header is marked by a special Magic Number, and both the header
3632 and the data portions of the image are secured against corruption by
3639 Although U-Boot should support any OS or standalone application
3640 easily, the main focus has always been on Linux during the design of
3643 U-Boot includes many features that so far have been part of some
3644 special "boot loader" code within the Linux kernel. Also, any
3645 "initrd" images to be used are no longer part of one big Linux image;
3646 instead, kernel and "initrd" are separate images. This implementation
3647 serves several purposes:
3649 - the same features can be used for other OS or standalone
3650 applications (for instance: using compressed images to reduce the
3651 Flash memory footprint)
3653 - it becomes much easier to port new Linux kernel versions because
3654 lots of low-level, hardware dependent stuff are done by U-Boot
3656 - the same Linux kernel image can now be used with different "initrd"
3657 images; of course this also means that different kernel images can
3658 be run with the same "initrd". This makes testing easier (you don't
3659 have to build a new "zImage.initrd" Linux image when you just
3660 change a file in your "initrd"). Also, a field-upgrade of the
3661 software is easier now.
3667 Porting Linux to U-Boot based systems:
3668 ---------------------------------------
3670 U-Boot cannot save you from doing all the necessary modifications to
3671 configure the Linux device drivers for use with your target hardware
3672 (no, we don't intend to provide a full virtual machine interface to
3675 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3677 Just make sure your machine specific header file (for instance
3678 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3679 Information structure as we define in include/asm-<arch>/u-boot.h,
3680 and make sure that your definition of IMAP_ADDR uses the same value
3681 as your U-Boot configuration in CONFIG_SYS_IMMR.
3684 Configuring the Linux kernel:
3685 -----------------------------
3687 No specific requirements for U-Boot. Make sure you have some root
3688 device (initial ramdisk, NFS) for your target system.
3691 Building a Linux Image:
3692 -----------------------
3694 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3695 not used. If you use recent kernel source, a new build target
3696 "uImage" will exist which automatically builds an image usable by
3697 U-Boot. Most older kernels also have support for a "pImage" target,
3698 which was introduced for our predecessor project PPCBoot and uses a
3699 100% compatible format.
3708 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3709 encapsulate a compressed Linux kernel image with header information,
3710 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3712 * build a standard "vmlinux" kernel image (in ELF binary format):
3714 * convert the kernel into a raw binary image:
3716 ${CROSS_COMPILE}-objcopy -O binary \
3717 -R .note -R .comment \
3718 -S vmlinux linux.bin
3720 * compress the binary image:
3724 * package compressed binary image for U-Boot:
3726 mkimage -A ppc -O linux -T kernel -C gzip \
3727 -a 0 -e 0 -n "Linux Kernel Image" \
3728 -d linux.bin.gz uImage
3731 The "mkimage" tool can also be used to create ramdisk images for use
3732 with U-Boot, either separated from the Linux kernel image, or
3733 combined into one file. "mkimage" encapsulates the images with a 64
3734 byte header containing information about target architecture,
3735 operating system, image type, compression method, entry points, time
3736 stamp, CRC32 checksums, etc.
3738 "mkimage" can be called in two ways: to verify existing images and
3739 print the header information, or to build new images.
3741 In the first form (with "-l" option) mkimage lists the information
3742 contained in the header of an existing U-Boot image; this includes
3743 checksum verification:
3745 tools/mkimage -l image
3746 -l ==> list image header information
3748 The second form (with "-d" option) is used to build a U-Boot image
3749 from a "data file" which is used as image payload:
3751 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3752 -n name -d data_file image
3753 -A ==> set architecture to 'arch'
3754 -O ==> set operating system to 'os'
3755 -T ==> set image type to 'type'
3756 -C ==> set compression type 'comp'
3757 -a ==> set load address to 'addr' (hex)
3758 -e ==> set entry point to 'ep' (hex)
3759 -n ==> set image name to 'name'
3760 -d ==> use image data from 'datafile'
3762 Right now, all Linux kernels for PowerPC systems use the same load
3763 address (0x00000000), but the entry point address depends on the
3766 - 2.2.x kernels have the entry point at 0x0000000C,
3767 - 2.3.x and later kernels have the entry point at 0x00000000.
3769 So a typical call to build a U-Boot image would read:
3771 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3772 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3773 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3774 > examples/uImage.TQM850L
3775 Image Name: 2.4.4 kernel for TQM850L
3776 Created: Wed Jul 19 02:34:59 2000
3777 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3778 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3779 Load Address: 0x00000000
3780 Entry Point: 0x00000000
3782 To verify the contents of the image (or check for corruption):
3784 -> tools/mkimage -l examples/uImage.TQM850L
3785 Image Name: 2.4.4 kernel for TQM850L
3786 Created: Wed Jul 19 02:34:59 2000
3787 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3788 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3789 Load Address: 0x00000000
3790 Entry Point: 0x00000000
3792 NOTE: for embedded systems where boot time is critical you can trade
3793 speed for memory and install an UNCOMPRESSED image instead: this
3794 needs more space in Flash, but boots much faster since it does not
3795 need to be uncompressed:
3797 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3798 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3799 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3800 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3801 > examples/uImage.TQM850L-uncompressed
3802 Image Name: 2.4.4 kernel for TQM850L
3803 Created: Wed Jul 19 02:34:59 2000
3804 Image Type: PowerPC Linux Kernel Image (uncompressed)
3805 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3806 Load Address: 0x00000000
3807 Entry Point: 0x00000000
3810 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3811 when your kernel is intended to use an initial ramdisk:
3813 -> tools/mkimage -n 'Simple Ramdisk Image' \
3814 > -A ppc -O linux -T ramdisk -C gzip \
3815 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3816 Image Name: Simple Ramdisk Image
3817 Created: Wed Jan 12 14:01:50 2000
3818 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3819 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3820 Load Address: 0x00000000
3821 Entry Point: 0x00000000
3824 Installing a Linux Image:
3825 -------------------------
3827 To downloading a U-Boot image over the serial (console) interface,
3828 you must convert the image to S-Record format:
3830 objcopy -I binary -O srec examples/image examples/image.srec
3832 The 'objcopy' does not understand the information in the U-Boot
3833 image header, so the resulting S-Record file will be relative to
3834 address 0x00000000. To load it to a given address, you need to
3835 specify the target address as 'offset' parameter with the 'loads'
3838 Example: install the image to address 0x40100000 (which on the
3839 TQM8xxL is in the first Flash bank):
3841 => erase 40100000 401FFFFF
3847 ## Ready for S-Record download ...
3848 ~>examples/image.srec
3849 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3851 15989 15990 15991 15992
3852 [file transfer complete]
3854 ## Start Addr = 0x00000000
3857 You can check the success of the download using the 'iminfo' command;
3858 this includes a checksum verification so you can be sure no data
3859 corruption happened:
3863 ## Checking Image at 40100000 ...
3864 Image Name: 2.2.13 for initrd on TQM850L
3865 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3866 Data Size: 335725 Bytes = 327 kB = 0 MB
3867 Load Address: 00000000
3868 Entry Point: 0000000c
3869 Verifying Checksum ... OK
3875 The "bootm" command is used to boot an application that is stored in
3876 memory (RAM or Flash). In case of a Linux kernel image, the contents
3877 of the "bootargs" environment variable is passed to the kernel as
3878 parameters. You can check and modify this variable using the
3879 "printenv" and "setenv" commands:
3882 => printenv bootargs
3883 bootargs=root=/dev/ram
3885 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3887 => printenv bootargs
3888 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3891 ## Booting Linux kernel at 40020000 ...
3892 Image Name: 2.2.13 for NFS on TQM850L
3893 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3894 Data Size: 381681 Bytes = 372 kB = 0 MB
3895 Load Address: 00000000
3896 Entry Point: 0000000c
3897 Verifying Checksum ... OK
3898 Uncompressing Kernel Image ... OK
3899 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
3900 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3901 time_init: decrementer frequency = 187500000/60
3902 Calibrating delay loop... 49.77 BogoMIPS
3903 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3906 If you want to boot a Linux kernel with initial RAM disk, you pass
3907 the memory addresses of both the kernel and the initrd image (PPBCOOT
3908 format!) to the "bootm" command:
3910 => imi 40100000 40200000
3912 ## Checking Image at 40100000 ...
3913 Image Name: 2.2.13 for initrd on TQM850L
3914 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3915 Data Size: 335725 Bytes = 327 kB = 0 MB
3916 Load Address: 00000000
3917 Entry Point: 0000000c
3918 Verifying Checksum ... OK
3920 ## Checking Image at 40200000 ...
3921 Image Name: Simple Ramdisk Image
3922 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3923 Data Size: 566530 Bytes = 553 kB = 0 MB
3924 Load Address: 00000000
3925 Entry Point: 00000000
3926 Verifying Checksum ... OK
3928 => bootm 40100000 40200000
3929 ## Booting Linux kernel at 40100000 ...
3930 Image Name: 2.2.13 for initrd on TQM850L
3931 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3932 Data Size: 335725 Bytes = 327 kB = 0 MB
3933 Load Address: 00000000
3934 Entry Point: 0000000c
3935 Verifying Checksum ... OK
3936 Uncompressing Kernel Image ... OK
3937 ## Loading RAMDisk Image at 40200000 ...
3938 Image Name: Simple Ramdisk Image
3939 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3940 Data Size: 566530 Bytes = 553 kB = 0 MB
3941 Load Address: 00000000
3942 Entry Point: 00000000
3943 Verifying Checksum ... OK
3944 Loading Ramdisk ... OK
3945 Linux version 2.2.13 (
[email protected]) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
3946 Boot arguments: root=/dev/ram
3947 time_init: decrementer frequency = 187500000/60
3948 Calibrating delay loop... 49.77 BogoMIPS
3950 RAMDISK: Compressed image found at block 0
3951 VFS: Mounted root (ext2 filesystem).
3955 Boot Linux and pass a flat device tree:
3958 First, U-Boot must be compiled with the appropriate defines. See the section
3959 titled "Linux Kernel Interface" above for a more in depth explanation. The
3960 following is an example of how to start a kernel and pass an updated
3966 oft=oftrees/mpc8540ads.dtb
3967 => tftp $oftaddr $oft
3968 Speed: 1000, full duplex
3970 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3971 Filename 'oftrees/mpc8540ads.dtb'.
3972 Load address: 0x300000
3975 Bytes transferred = 4106 (100a hex)
3976 => tftp $loadaddr $bootfile
3977 Speed: 1000, full duplex
3979 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3981 Load address: 0x200000
3982 Loading:############
3984 Bytes transferred = 1029407 (fb51f hex)
3989 => bootm $loadaddr - $oftaddr
3990 ## Booting image at 00200000 ...
3991 Image Name: Linux-2.6.17-dirty
3992 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3993 Data Size: 1029343 Bytes = 1005.2 kB
3994 Load Address: 00000000
3995 Entry Point: 00000000
3996 Verifying Checksum ... OK
3997 Uncompressing Kernel Image ... OK
3998 Booting using flat device tree at 0x300000
3999 Using MPC85xx ADS machine description
4000 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4004 More About U-Boot Image Types:
4005 ------------------------------
4007 U-Boot supports the following image types:
4009 "Standalone Programs" are directly runnable in the environment
4010 provided by U-Boot; it is expected that (if they behave
4011 well) you can continue to work in U-Boot after return from
4012 the Standalone Program.
4013 "OS Kernel Images" are usually images of some Embedded OS which
4014 will take over control completely. Usually these programs
4015 will install their own set of exception handlers, device
4016 drivers, set up the MMU, etc. - this means, that you cannot
4017 expect to re-enter U-Boot except by resetting the CPU.
4018 "RAMDisk Images" are more or less just data blocks, and their
4019 parameters (address, size) are passed to an OS kernel that is
4021 "Multi-File Images" contain several images, typically an OS
4022 (Linux) kernel image and one or more data images like
4023 RAMDisks. This construct is useful for instance when you want
4024 to boot over the network using BOOTP etc., where the boot
4025 server provides just a single image file, but you want to get
4026 for instance an OS kernel and a RAMDisk image.
4028 "Multi-File Images" start with a list of image sizes, each
4029 image size (in bytes) specified by an "uint32_t" in network
4030 byte order. This list is terminated by an "(uint32_t)0".
4031 Immediately after the terminating 0 follow the images, one by
4032 one, all aligned on "uint32_t" boundaries (size rounded up to
4033 a multiple of 4 bytes).
4035 "Firmware Images" are binary images containing firmware (like
4036 U-Boot or FPGA images) which usually will be programmed to
4039 "Script files" are command sequences that will be executed by
4040 U-Boot's command interpreter; this feature is especially
4041 useful when you configure U-Boot to use a real shell (hush)
4042 as command interpreter.
4048 One of the features of U-Boot is that you can dynamically load and
4049 run "standalone" applications, which can use some resources of
4050 U-Boot like console I/O functions or interrupt services.
4052 Two simple examples are included with the sources:
4057 'examples/hello_world.c' contains a small "Hello World" Demo
4058 application; it is automatically compiled when you build U-Boot.
4059 It's configured to run at address 0x00040004, so you can play with it
4063 ## Ready for S-Record download ...
4064 ~>examples/hello_world.srec
4065 1 2 3 4 5 6 7 8 9 10 11 ...
4066 [file transfer complete]
4068 ## Start Addr = 0x00040004
4070 => go 40004 Hello World! This is a test.
4071 ## Starting application at 0x00040004 ...
4082 Hit any key to exit ...
4084 ## Application terminated, rc = 0x0
4086 Another example, which demonstrates how to register a CPM interrupt
4087 handler with the U-Boot code, can be found in 'examples/timer.c'.
4088 Here, a CPM timer is set up to generate an interrupt every second.
4089 The interrupt service routine is trivial, just printing a '.'
4090 character, but this is just a demo program. The application can be
4091 controlled by the following keys:
4093 ? - print current values og the CPM Timer registers
4094 b - enable interrupts and start timer
4095 e - stop timer and disable interrupts
4096 q - quit application
4099 ## Ready for S-Record download ...
4100 ~>examples/timer.srec
4101 1 2 3 4 5 6 7 8 9 10 11 ...
4102 [file transfer complete]
4104 ## Start Addr = 0x00040004
4107 ## Starting application at 0x00040004 ...
4110 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4113 [q, b, e, ?] Set interval 1000000 us
4116 [q, b, e, ?] ........
4117 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4120 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4123 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4126 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4128 [q, b, e, ?] ...Stopping timer
4130 [q, b, e, ?] ## Application terminated, rc = 0x0
4136 Over time, many people have reported problems when trying to use the
4137 "minicom" terminal emulation program for serial download. I (wd)
4138 consider minicom to be broken, and recommend not to use it. Under
4139 Unix, I recommend to use C-Kermit for general purpose use (and
4140 especially for kermit binary protocol download ("loadb" command), and
4141 use "cu" for S-Record download ("loads" command).
4143 Nevertheless, if you absolutely want to use it try adding this
4144 configuration to your "File transfer protocols" section:
4146 Name Program Name U/D FullScr IO-Red. Multi
4147 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4148 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4154 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4155 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4157 Building requires a cross environment; it is known to work on
4158 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4159 need gmake since the Makefiles are not compatible with BSD make).
4160 Note that the cross-powerpc package does not install include files;
4161 attempting to build U-Boot will fail because <machine/ansi.h> is
4162 missing. This file has to be installed and patched manually:
4164 # cd /usr/pkg/cross/powerpc-netbsd/include
4166 # ln -s powerpc machine
4167 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4168 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4170 Native builds *don't* work due to incompatibilities between native
4171 and U-Boot include files.
4173 Booting assumes that (the first part of) the image booted is a
4174 stage-2 loader which in turn loads and then invokes the kernel
4175 proper. Loader sources will eventually appear in the NetBSD source
4176 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4177 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4180 Implementation Internals:
4181 =========================
4183 The following is not intended to be a complete description of every
4184 implementation detail. However, it should help to understand the
4185 inner workings of U-Boot and make it easier to port it to custom
4189 Initial Stack, Global Data:
4190 ---------------------------
4192 The implementation of U-Boot is complicated by the fact that U-Boot
4193 starts running out of ROM (flash memory), usually without access to
4194 system RAM (because the memory controller is not initialized yet).
4195 This means that we don't have writable Data or BSS segments, and BSS
4196 is not initialized as zero. To be able to get a C environment working
4197 at all, we have to allocate at least a minimal stack. Implementation
4198 options for this are defined and restricted by the CPU used: Some CPU
4199 models provide on-chip memory (like the IMMR area on MPC8xx and
4200 MPC826x processors), on others (parts of) the data cache can be
4201 locked as (mis-) used as memory, etc.
4203 Chris Hallinan posted a good summary of these issues to the
4204 U-Boot mailing list:
4206 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4208 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4211 Correct me if I'm wrong, folks, but the way I understand it
4212 is this: Using DCACHE as initial RAM for Stack, etc, does not
4213 require any physical RAM backing up the cache. The cleverness
4214 is that the cache is being used as a temporary supply of
4215 necessary storage before the SDRAM controller is setup. It's
4216 beyond the scope of this list to explain the details, but you
4217 can see how this works by studying the cache architecture and
4218 operation in the architecture and processor-specific manuals.
4220 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4221 is another option for the system designer to use as an
4222 initial stack/RAM area prior to SDRAM being available. Either
4223 option should work for you. Using CS 4 should be fine if your
4224 board designers haven't used it for something that would
4225 cause you grief during the initial boot! It is frequently not
4228 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4229 with your processor/board/system design. The default value
4230 you will find in any recent u-boot distribution in
4231 walnut.h should work for you. I'd set it to a value larger
4232 than your SDRAM module. If you have a 64MB SDRAM module, set
4233 it above 400_0000. Just make sure your board has no resources
4234 that are supposed to respond to that address! That code in
4235 start.S has been around a while and should work as is when
4236 you get the config right.
4241 It is essential to remember this, since it has some impact on the C
4242 code for the initialization procedures:
4244 * Initialized global data (data segment) is read-only. Do not attempt
4247 * Do not use any uninitialized global data (or implicitely initialized
4248 as zero data - BSS segment) at all - this is undefined, initiali-
4249 zation is performed later (when relocating to RAM).
4251 * Stack space is very limited. Avoid big data buffers or things like
4254 Having only the stack as writable memory limits means we cannot use
4255 normal global data to share information beween the code. But it
4256 turned out that the implementation of U-Boot can be greatly
4257 simplified by making a global data structure (gd_t) available to all
4258 functions. We could pass a pointer to this data as argument to _all_
4259 functions, but this would bloat the code. Instead we use a feature of
4260 the GCC compiler (Global Register Variables) to share the data: we
4261 place a pointer (gd) to the global data into a register which we
4262 reserve for this purpose.
4264 When choosing a register for such a purpose we are restricted by the
4265 relevant (E)ABI specifications for the current architecture, and by
4266 GCC's implementation.
4268 For PowerPC, the following registers have specific use:
4270 R2: reserved for system use
4271 R3-R4: parameter passing and return values
4272 R5-R10: parameter passing
4273 R13: small data area pointer
4277 (U-Boot also uses R12 as internal GOT pointer. r12
4278 is a volatile register so r12 needs to be reset when
4279 going back and forth between asm and C)
4281 ==> U-Boot will use R2 to hold a pointer to the global data
4283 Note: on PPC, we could use a static initializer (since the
4284 address of the global data structure is known at compile time),
4285 but it turned out that reserving a register results in somewhat
4286 smaller code - although the code savings are not that big (on
4287 average for all boards 752 bytes for the whole U-Boot image,
4288 624 text + 127 data).
4290 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4291 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4293 ==> U-Boot will use P3 to hold a pointer to the global data
4295 On ARM, the following registers are used:
4297 R0: function argument word/integer result
4298 R1-R3: function argument word
4300 R10: stack limit (used only if stack checking if enabled)
4301 R11: argument (frame) pointer
4302 R12: temporary workspace
4305 R15: program counter
4307 ==> U-Boot will use R8 to hold a pointer to the global data
4309 On Nios II, the ABI is documented here:
4310 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4312 ==> U-Boot will use gp to hold a pointer to the global data
4314 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4315 to access small data sections, so gp is free.
4317 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4318 or current versions of GCC may "optimize" the code too much.
4323 U-Boot runs in system state and uses physical addresses, i.e. the
4324 MMU is not used either for address mapping nor for memory protection.
4326 The available memory is mapped to fixed addresses using the memory
4327 controller. In this process, a contiguous block is formed for each
4328 memory type (Flash, SDRAM, SRAM), even when it consists of several
4329 physical memory banks.
4331 U-Boot is installed in the first 128 kB of the first Flash bank (on
4332 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4333 booting and sizing and initializing DRAM, the code relocates itself
4334 to the upper end of DRAM. Immediately below the U-Boot code some
4335 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4336 configuration setting]. Below that, a structure with global Board
4337 Info data is placed, followed by the stack (growing downward).
4339 Additionally, some exception handler code is copied to the low 8 kB
4340 of DRAM (0x00000000 ... 0x00001FFF).
4342 So a typical memory configuration with 16 MB of DRAM could look like
4345 0x0000 0000 Exception Vector code
4348 0x0000 2000 Free for Application Use
4354 0x00FB FF20 Monitor Stack (Growing downward)
4355 0x00FB FFAC Board Info Data and permanent copy of global data
4356 0x00FC 0000 Malloc Arena
4359 0x00FE 0000 RAM Copy of Monitor Code
4360 ... eventually: LCD or video framebuffer
4361 ... eventually: pRAM (Protected RAM - unchanged by reset)
4362 0x00FF FFFF [End of RAM]
4365 System Initialization:
4366 ----------------------
4368 In the reset configuration, U-Boot starts at the reset entry point
4369 (on most PowerPC systems at address 0x00000100). Because of the reset
4370 configuration for CS0# this is a mirror of the onboard Flash memory.
4371 To be able to re-map memory U-Boot then jumps to its link address.
4372 To be able to implement the initialization code in C, a (small!)
4373 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4374 which provide such a feature like MPC8xx or MPC8260), or in a locked
4375 part of the data cache. After that, U-Boot initializes the CPU core,
4376 the caches and the SIU.
4378 Next, all (potentially) available memory banks are mapped using a
4379 preliminary mapping. For example, we put them on 512 MB boundaries
4380 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4381 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4382 programmed for SDRAM access. Using the temporary configuration, a
4383 simple memory test is run that determines the size of the SDRAM
4386 When there is more than one SDRAM bank, and the banks are of
4387 different size, the largest is mapped first. For equal size, the first
4388 bank (CS2#) is mapped first. The first mapping is always for address
4389 0x00000000, with any additional banks following immediately to create
4390 contiguous memory starting from 0.
4392 Then, the monitor installs itself at the upper end of the SDRAM area
4393 and allocates memory for use by malloc() and for the global Board
4394 Info data; also, the exception vector code is copied to the low RAM
4395 pages, and the final stack is set up.
4397 Only after this relocation will you have a "normal" C environment;
4398 until that you are restricted in several ways, mostly because you are
4399 running from ROM, and because the code will have to be relocated to a
4403 U-Boot Porting Guide:
4404 ----------------------
4406 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4410 int main(int argc, char *argv[])
4412 sighandler_t no_more_time;
4414 signal(SIGALRM, no_more_time);
4415 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4417 if (available_money > available_manpower) {
4418 Pay consultant to port U-Boot;
4422 Download latest U-Boot source;
4424 Subscribe to u-boot mailing list;
4427 email("Hi, I am new to U-Boot, how do I get started?");
4430 Read the README file in the top level directory;
4431 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4432 Read applicable doc/*.README;
4433 Read the source, Luke;
4434 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4437 if (available_money > toLocalCurrency ($2500))
4440 Add a lot of aggravation and time;
4442 if (a similar board exists) { /* hopefully... */
4443 cp -a board/<similar> board/<myboard>
4444 cp include/configs/<similar>.h include/configs/<myboard>.h
4446 Create your own board support subdirectory;
4447 Create your own board include/configs/<myboard>.h file;
4449 Edit new board/<myboard> files
4450 Edit new include/configs/<myboard>.h
4455 Add / modify source code;
4459 email("Hi, I am having problems...");
4461 Send patch file to the U-Boot email list;
4462 if (reasonable critiques)
4463 Incorporate improvements from email list code review;
4465 Defend code as written;
4471 void no_more_time (int sig)
4480 All contributions to U-Boot should conform to the Linux kernel
4481 coding style; see the file "Documentation/CodingStyle" and the script
4482 "scripts/Lindent" in your Linux kernel source directory.
4484 Source files originating from a different project (for example the
4485 MTD subsystem) are generally exempt from these guidelines and are not
4486 reformated to ease subsequent migration to newer versions of those
4489 Please note that U-Boot is implemented in C (and to some small parts in
4490 Assembler); no C++ is used, so please do not use C++ style comments (//)
4493 Please also stick to the following formatting rules:
4494 - remove any trailing white space
4495 - use TAB characters for indentation and vertical alignment, not spaces
4496 - make sure NOT to use DOS '\r\n' line feeds
4497 - do not add more than 2 consecutive empty lines to source files
4498 - do not add trailing empty lines to source files
4500 Submissions which do not conform to the standards may be returned
4501 with a request to reformat the changes.
4507 Since the number of patches for U-Boot is growing, we need to
4508 establish some rules. Submissions which do not conform to these rules
4509 may be rejected, even when they contain important and valuable stuff.
4511 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4514 see http://lists.denx.de/mailman/listinfo/u-boot
4516 When you send a patch, please include the following information with
4519 * For bug fixes: a description of the bug and how your patch fixes
4520 this bug. Please try to include a way of demonstrating that the
4521 patch actually fixes something.
4523 * For new features: a description of the feature and your
4526 * A CHANGELOG entry as plaintext (separate from the patch)
4528 * For major contributions, your entry to the CREDITS file
4530 * When you add support for a new board, don't forget to add this
4531 board to the MAINTAINERS file, too.
4533 * If your patch adds new configuration options, don't forget to
4534 document these in the README file.
4536 * The patch itself. If you are using git (which is *strongly*
4537 recommended) you can easily generate the patch using the
4538 "git format-patch". If you then use "git send-email" to send it to
4539 the U-Boot mailing list, you will avoid most of the common problems
4540 with some other mail clients.
4542 If you cannot use git, use "diff -purN OLD NEW". If your version of
4543 diff does not support these options, then get the latest version of
4546 The current directory when running this command shall be the parent
4547 directory of the U-Boot source tree (i. e. please make sure that
4548 your patch includes sufficient directory information for the
4551 We prefer patches as plain text. MIME attachments are discouraged,
4552 and compressed attachments must not be used.
4554 * If one logical set of modifications affects or creates several
4555 files, all these changes shall be submitted in a SINGLE patch file.
4557 * Changesets that contain different, unrelated modifications shall be
4558 submitted as SEPARATE patches, one patch per changeset.
4563 * Before sending the patch, run the MAKEALL script on your patched
4564 source tree and make sure that no errors or warnings are reported
4565 for any of the boards.
4567 * Keep your modifications to the necessary minimum: A patch
4568 containing several unrelated changes or arbitrary reformats will be
4569 returned with a request to re-formatting / split it.
4571 * If you modify existing code, make sure that your new code does not
4572 add to the memory footprint of the code ;-) Small is beautiful!
4573 When adding new features, these should compile conditionally only
4574 (using #ifdef), and the resulting code with the new feature
4575 disabled must not need more memory than the old code without your
4578 * Remember that there is a size limit of 100 kB per message on the
4579 u-boot mailing list. Bigger patches will be moderated. If they are
4580 reasonable and not too big, they will be acknowledged. But patches
4581 bigger than the size limit should be avoided.
projects / u-boot.git / blob