2 # (C) Copyright 2000 - 2009
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
359 - Intel Monahans options:
360 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
362 Defines the Monahans run mode to oscillator
363 ratio. Valid values are 8, 16, 24, 31. The core
364 frequency is this value multiplied by 13 MHz.
366 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
368 Defines the Monahans turbo mode to oscillator
369 ratio. Valid values are 1 (default if undefined) and
370 2. The core frequency as calculated above is multiplied
373 - Linux Kernel Interface:
376 U-Boot stores all clock information in Hz
377 internally. For binary compatibility with older Linux
378 kernels (which expect the clocks passed in the
379 bd_info data to be in MHz) the environment variable
380 "clocks_in_mhz" can be defined so that U-Boot
381 converts clock data to MHZ before passing it to the
383 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
384 "clocks_in_mhz=1" is automatically included in the
387 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
389 When transferring memsize parameter to linux, some versions
390 expect it to be in bytes, others in MB.
391 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
395 New kernel versions are expecting firmware settings to be
396 passed using flattened device trees (based on open firmware
400 * New libfdt-based support
401 * Adds the "fdt" command
402 * The bootm command automatically updates the fdt
404 OF_CPU - The proper name of the cpus node (only required for
405 MPC512X and MPC5xxx based boards).
406 OF_SOC - The proper name of the soc node (only required for
407 MPC512X and MPC5xxx based boards).
408 OF_TBCLK - The timebase frequency.
409 OF_STDOUT_PATH - The path to the console device
411 boards with QUICC Engines require OF_QE to set UCC MAC
414 CONFIG_OF_BOARD_SETUP
416 Board code has addition modification that it wants to make
417 to the flat device tree before handing it off to the kernel
421 This define fills in the correct boot CPU in the boot
422 param header, the default value is zero if undefined.
426 U-Boot can detect if an IDE device is present or not.
427 If not, and this new config option is activated, U-Boot
428 removes the ATA node from the DTS before booting Linux,
429 so the Linux IDE driver does not probe the device and
430 crash. This is needed for buggy hardware (uc101) where
431 no pull down resistor is connected to the signal IDE5V_DD7.
433 - vxWorks boot parameters:
435 bootvx constructs a valid bootline using the following
436 environments variables: bootfile, ipaddr, serverip, hostname.
437 It loads the vxWorks image pointed bootfile.
439 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
440 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
441 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
442 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
444 CONFIG_SYS_VXWORKS_ADD_PARAMS
446 Add it at the end of the bootline. E.g "u=username pw=secret"
448 Note: If a "bootargs" environment is defined, it will overwride
449 the defaults discussed just above.
454 Define this if you want support for Amba PrimeCell PL010 UARTs.
458 Define this if you want support for Amba PrimeCell PL011 UARTs.
462 If you have Amba PrimeCell PL011 UARTs, set this variable to
463 the clock speed of the UARTs.
467 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
468 define this to a list of base addresses for each (supported)
469 port. See e.g. include/configs/versatile.h
473 Depending on board, define exactly one serial port
474 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
475 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
476 console by defining CONFIG_8xx_CONS_NONE
478 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
479 port routines must be defined elsewhere
480 (i.e. serial_init(), serial_getc(), ...)
483 Enables console device for a color framebuffer. Needs following
484 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
485 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
487 VIDEO_HW_RECTFILL graphic chip supports
490 VIDEO_HW_BITBLT graphic chip supports
491 bit-blit (cf. smiLynxEM)
492 VIDEO_VISIBLE_COLS visible pixel columns
494 VIDEO_VISIBLE_ROWS visible pixel rows
495 VIDEO_PIXEL_SIZE bytes per pixel
496 VIDEO_DATA_FORMAT graphic data format
497 (0-5, cf. cfb_console.c)
498 VIDEO_FB_ADRS framebuffer address
499 VIDEO_KBD_INIT_FCT keyboard int fct
500 (i.e. i8042_kbd_init())
501 VIDEO_TSTC_FCT test char fct
503 VIDEO_GETC_FCT get char fct
505 CONFIG_CONSOLE_CURSOR cursor drawing on/off
506 (requires blink timer
508 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
509 CONFIG_CONSOLE_TIME display time/date info in
511 (requires CONFIG_CMD_DATE)
512 CONFIG_VIDEO_LOGO display Linux logo in
514 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
515 linux_logo.h for logo.
516 Requires CONFIG_VIDEO_LOGO
517 CONFIG_CONSOLE_EXTRA_INFO
518 additional board info beside
521 When CONFIG_CFB_CONSOLE is defined, video console is
522 default i/o. Serial console can be forced with
523 environment 'console=serial'.
525 When CONFIG_SILENT_CONSOLE is defined, all console
526 messages (by U-Boot and Linux!) can be silenced with
527 the "silent" environment variable. See
528 doc/README.silent for more information.
531 CONFIG_BAUDRATE - in bps
532 Select one of the baudrates listed in
533 CONFIG_SYS_BAUDRATE_TABLE, see below.
534 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
536 - Console Rx buffer length
537 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
538 the maximum receive buffer length for the SMC.
539 This option is actual only for 82xx and 8xx possible.
540 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
541 must be defined, to setup the maximum idle timeout for
544 - Boot Delay: CONFIG_BOOTDELAY - in seconds
545 Delay before automatically booting the default image;
546 set to -1 to disable autoboot.
548 See doc/README.autoboot for these options that
549 work with CONFIG_BOOTDELAY. None are required.
550 CONFIG_BOOT_RETRY_TIME
551 CONFIG_BOOT_RETRY_MIN
552 CONFIG_AUTOBOOT_KEYED
553 CONFIG_AUTOBOOT_PROMPT
554 CONFIG_AUTOBOOT_DELAY_STR
555 CONFIG_AUTOBOOT_STOP_STR
556 CONFIG_AUTOBOOT_DELAY_STR2
557 CONFIG_AUTOBOOT_STOP_STR2
558 CONFIG_ZERO_BOOTDELAY_CHECK
559 CONFIG_RESET_TO_RETRY
563 Only needed when CONFIG_BOOTDELAY is enabled;
564 define a command string that is automatically executed
565 when no character is read on the console interface
566 within "Boot Delay" after reset.
569 This can be used to pass arguments to the bootm
570 command. The value of CONFIG_BOOTARGS goes into the
571 environment value "bootargs".
573 CONFIG_RAMBOOT and CONFIG_NFSBOOT
574 The value of these goes into the environment as
575 "ramboot" and "nfsboot" respectively, and can be used
576 as a convenience, when switching between booting from
582 When this option is #defined, the existence of the
583 environment variable "preboot" will be checked
584 immediately before starting the CONFIG_BOOTDELAY
585 countdown and/or running the auto-boot command resp.
586 entering interactive mode.
588 This feature is especially useful when "preboot" is
589 automatically generated or modified. For an example
590 see the LWMON board specific code: here "preboot" is
591 modified when the user holds down a certain
592 combination of keys on the (special) keyboard when
595 - Serial Download Echo Mode:
597 If defined to 1, all characters received during a
598 serial download (using the "loads" command) are
599 echoed back. This might be needed by some terminal
600 emulations (like "cu"), but may as well just take
601 time on others. This setting #define's the initial
602 value of the "loads_echo" environment variable.
604 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
606 Select one of the baudrates listed in
607 CONFIG_SYS_BAUDRATE_TABLE, see below.
610 Monitor commands can be included or excluded
611 from the build by using the #include files
612 "config_cmd_all.h" and #undef'ing unwanted
613 commands, or using "config_cmd_default.h"
614 and augmenting with additional #define's
617 The default command configuration includes all commands
618 except those marked below with a "*".
620 CONFIG_CMD_ASKENV * ask for env variable
621 CONFIG_CMD_BDI bdinfo
622 CONFIG_CMD_BEDBUG * Include BedBug Debugger
623 CONFIG_CMD_BMP * BMP support
624 CONFIG_CMD_BSP * Board specific commands
625 CONFIG_CMD_BOOTD bootd
626 CONFIG_CMD_CACHE * icache, dcache
627 CONFIG_CMD_CONSOLE coninfo
628 CONFIG_CMD_CRC32 * crc32
629 CONFIG_CMD_DATE * support for RTC, date/time...
630 CONFIG_CMD_DHCP * DHCP support
631 CONFIG_CMD_DIAG * Diagnostics
632 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
633 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
634 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
635 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
636 CONFIG_CMD_DTT * Digital Therm and Thermostat
637 CONFIG_CMD_ECHO echo arguments
638 CONFIG_CMD_EDITENV edit env variable
639 CONFIG_CMD_EEPROM * EEPROM read/write support
640 CONFIG_CMD_ELF * bootelf, bootvx
641 CONFIG_CMD_EXPORTENV * export the environment
642 CONFIG_CMD_SAVEENV saveenv
643 CONFIG_CMD_FDC * Floppy Disk Support
644 CONFIG_CMD_FAT * FAT partition support
645 CONFIG_CMD_FDOS * Dos diskette Support
646 CONFIG_CMD_FLASH flinfo, erase, protect
647 CONFIG_CMD_FPGA FPGA device initialization support
648 CONFIG_CMD_GO * the 'go' command (exec code)
649 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
650 CONFIG_CMD_I2C * I2C serial bus support
651 CONFIG_CMD_IDE * IDE harddisk support
652 CONFIG_CMD_IMI iminfo
653 CONFIG_CMD_IMLS List all found images
654 CONFIG_CMD_IMMAP * IMMR dump support
655 CONFIG_CMD_IMPORTENV * import an environment
656 CONFIG_CMD_IRQ * irqinfo
657 CONFIG_CMD_ITEST Integer/string test of 2 values
658 CONFIG_CMD_JFFS2 * JFFS2 Support
659 CONFIG_CMD_KGDB * kgdb
660 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
661 CONFIG_CMD_LOADB loadb
662 CONFIG_CMD_LOADS loads
663 CONFIG_CMD_MD5SUM print md5 message digest
664 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
665 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
667 CONFIG_CMD_MISC Misc functions like sleep etc
668 CONFIG_CMD_MMC * MMC memory mapped support
669 CONFIG_CMD_MII * MII utility commands
670 CONFIG_CMD_MTDPARTS * MTD partition support
671 CONFIG_CMD_NAND * NAND support
672 CONFIG_CMD_NET bootp, tftpboot, rarpboot
673 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
674 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
675 CONFIG_CMD_PCI * pciinfo
676 CONFIG_CMD_PCMCIA * PCMCIA support
677 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
679 CONFIG_CMD_PORTIO * Port I/O
680 CONFIG_CMD_REGINFO * Register dump
681 CONFIG_CMD_RUN run command in env variable
682 CONFIG_CMD_SAVES * save S record dump
683 CONFIG_CMD_SCSI * SCSI Support
684 CONFIG_CMD_SDRAM * print SDRAM configuration information
685 (requires CONFIG_CMD_I2C)
686 CONFIG_CMD_SETGETDCR Support for DCR Register access
688 CONFIG_CMD_SHA1SUM print sha1 memory digest
689 (requires CONFIG_CMD_MEMORY)
690 CONFIG_CMD_SOURCE "source" command Support
691 CONFIG_CMD_SPI * SPI serial bus support
692 CONFIG_CMD_USB * USB support
693 CONFIG_CMD_VFD * VFD support (TRAB)
694 CONFIG_CMD_CDP * Cisco Discover Protocol support
695 CONFIG_CMD_FSL * Microblaze FSL support
698 EXAMPLE: If you want all functions except of network
699 support you can write:
701 #include "config_cmd_all.h"
702 #undef CONFIG_CMD_NET
705 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
707 Note: Don't enable the "icache" and "dcache" commands
708 (configuration option CONFIG_CMD_CACHE) unless you know
709 what you (and your U-Boot users) are doing. Data
710 cache cannot be enabled on systems like the 8xx or
711 8260 (where accesses to the IMMR region must be
712 uncached), and it cannot be disabled on all other
713 systems where we (mis-) use the data cache to hold an
714 initial stack and some data.
717 XXX - this list needs to get updated!
721 If this variable is defined, it enables watchdog
722 support. There must be support in the platform specific
723 code for a watchdog. For the 8xx and 8260 CPUs, the
724 SIU Watchdog feature is enabled in the SYPCR
728 CONFIG_VERSION_VARIABLE
729 If this variable is defined, an environment variable
730 named "ver" is created by U-Boot showing the U-Boot
731 version as printed by the "version" command.
732 This variable is readonly.
736 When CONFIG_CMD_DATE is selected, the type of the RTC
737 has to be selected, too. Define exactly one of the
740 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
741 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
742 CONFIG_RTC_MC13783 - use MC13783 RTC
743 CONFIG_RTC_MC146818 - use MC146818 RTC
744 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
745 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
746 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
747 CONFIG_RTC_DS164x - use Dallas DS164x RTC
748 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
749 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
750 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
751 CONFIG_SYS_RV3029_TCR - enable trickle charger on
754 Note that if the RTC uses I2C, then the I2C interface
755 must also be configured. See I2C Support, below.
758 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
759 CONFIG_PCA953X_INFO - enable pca953x info command
761 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
762 chip-ngpio pairs that tell the PCA953X driver the number of
763 pins supported by a particular chip.
765 Note that if the GPIO device uses I2C, then the I2C interface
766 must also be configured. See I2C Support, below.
770 When CONFIG_TIMESTAMP is selected, the timestamp
771 (date and time) of an image is printed by image
772 commands like bootm or iminfo. This option is
773 automatically enabled when you select CONFIG_CMD_DATE .
776 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
777 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
779 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
780 CONFIG_CMD_SCSI) you must configure support for at
781 least one partition type as well.
784 CONFIG_IDE_RESET_ROUTINE - this is defined in several
785 board configurations files but used nowhere!
787 CONFIG_IDE_RESET - is this is defined, IDE Reset will
788 be performed by calling the function
789 ide_set_reset(int reset)
790 which has to be defined in a board specific file
795 Set this to enable ATAPI support.
800 Set this to enable support for disks larger than 137GB
801 Also look at CONFIG_SYS_64BIT_LBA.
802 Whithout these , LBA48 support uses 32bit variables and will 'only'
803 support disks up to 2.1TB.
805 CONFIG_SYS_64BIT_LBA:
806 When enabled, makes the IDE subsystem use 64bit sector addresses.
810 At the moment only there is only support for the
811 SYM53C8XX SCSI controller; define
812 CONFIG_SCSI_SYM53C8XX to enable it.
814 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
815 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
816 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
817 maximum numbers of LUNs, SCSI ID's and target
819 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
821 - NETWORK Support (PCI):
823 Support for Intel 8254x gigabit chips.
825 CONFIG_E1000_FALLBACK_MAC
826 default MAC for empty EEPROM after production.
829 Support for Intel 82557/82559/82559ER chips.
830 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
831 write routine for first time initialisation.
834 Support for Digital 2114x chips.
835 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
836 modem chip initialisation (KS8761/QS6611).
839 Support for National dp83815 chips.
842 Support for National dp8382[01] gigabit chips.
844 - NETWORK Support (other):
846 CONFIG_DRIVER_AT91EMAC
847 Support for AT91RM9200 EMAC.
850 Define this to use reduced MII inteface
852 CONFIG_DRIVER_AT91EMAC_QUIET
853 If this defined, the driver is quiet.
854 The driver doen't show link status messages.
856 CONFIG_DRIVER_LAN91C96
857 Support for SMSC's LAN91C96 chips.
860 Define this to hold the physical address
861 of the LAN91C96's I/O space
863 CONFIG_LAN91C96_USE_32_BIT
864 Define this to enable 32 bit addressing
866 CONFIG_DRIVER_SMC91111
867 Support for SMSC's LAN91C111 chip
870 Define this to hold the physical address
871 of the device (I/O space)
873 CONFIG_SMC_USE_32_BIT
874 Define this if data bus is 32 bits
876 CONFIG_SMC_USE_IOFUNCS
877 Define this to use i/o functions instead of macros
878 (some hardware wont work with macros)
881 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
883 CONFIG_FTGMAC100_EGIGA
884 Define this to use GE link update with gigabit PHY.
885 Define this if FTGMAC100 is connected to gigabit PHY.
886 If your system has 10/100 PHY only, it might not occur
887 wrong behavior. Because PHY usually return timeout or
888 useless data when polling gigabit status and gigabit
889 control registers. This behavior won't affect the
890 correctnessof 10/100 link speed update.
893 Support for SMSC's LAN911x and LAN921x chips
896 Define this to hold the physical address
897 of the device (I/O space)
899 CONFIG_SMC911X_32_BIT
900 Define this if data bus is 32 bits
902 CONFIG_SMC911X_16_BIT
903 Define this if data bus is 16 bits. If your processor
904 automatically converts one 32 bit word to two 16 bit
905 words you may also try CONFIG_SMC911X_32_BIT.
908 Support for Renesas on-chip Ethernet controller
910 CONFIG_SH_ETHER_USE_PORT
911 Define the number of ports to be used
913 CONFIG_SH_ETHER_PHY_ADDR
914 Define the ETH PHY's address
916 CONFIG_SH_ETHER_CACHE_WRITEBACK
917 If this option is set, the driver enables cache flush.
920 At the moment only the UHCI host controller is
921 supported (PIP405, MIP405, MPC5200); define
922 CONFIG_USB_UHCI to enable it.
923 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
924 and define CONFIG_USB_STORAGE to enable the USB
927 Supported are USB Keyboards and USB Floppy drives
929 MPC5200 USB requires additional defines:
931 for 528 MHz Clock: 0x0001bbbb
935 for differential drivers: 0x00001000
936 for single ended drivers: 0x00005000
937 for differential drivers on PSC3: 0x00000100
938 for single ended drivers on PSC3: 0x00004100
939 CONFIG_SYS_USB_EVENT_POLL
940 May be defined to allow interrupt polling
941 instead of using asynchronous interrupts
944 Define the below if you wish to use the USB console.
945 Once firmware is rebuilt from a serial console issue the
946 command "setenv stdin usbtty; setenv stdout usbtty" and
947 attach your USB cable. The Unix command "dmesg" should print
948 it has found a new device. The environment variable usbtty
949 can be set to gserial or cdc_acm to enable your device to
950 appear to a USB host as a Linux gserial device or a
951 Common Device Class Abstract Control Model serial device.
952 If you select usbtty = gserial you should be able to enumerate
954 # modprobe usbserial vendor=0xVendorID product=0xProductID
955 else if using cdc_acm, simply setting the environment
956 variable usbtty to be cdc_acm should suffice. The following
957 might be defined in YourBoardName.h
960 Define this to build a UDC device
963 Define this to have a tty type of device available to
964 talk to the UDC device
966 CONFIG_SYS_CONSOLE_IS_IN_ENV
967 Define this if you want stdin, stdout &/or stderr to
971 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
972 Derive USB clock from external clock "blah"
973 - CONFIG_SYS_USB_EXTC_CLK 0x02
975 CONFIG_SYS_USB_BRG_CLK 0xBLAH
976 Derive USB clock from brgclk
977 - CONFIG_SYS_USB_BRG_CLK 0x04
979 If you have a USB-IF assigned VendorID then you may wish to
980 define your own vendor specific values either in BoardName.h
981 or directly in usbd_vendor_info.h. If you don't define
982 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
983 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
984 should pretend to be a Linux device to it's target host.
986 CONFIG_USBD_MANUFACTURER
987 Define this string as the name of your company for
988 - CONFIG_USBD_MANUFACTURER "my company"
990 CONFIG_USBD_PRODUCT_NAME
991 Define this string as the name of your product
992 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
995 Define this as your assigned Vendor ID from the USB
996 Implementors Forum. This *must* be a genuine Vendor ID
997 to avoid polluting the USB namespace.
998 - CONFIG_USBD_VENDORID 0xFFFF
1000 CONFIG_USBD_PRODUCTID
1001 Define this as the unique Product ID
1003 - CONFIG_USBD_PRODUCTID 0xFFFF
1007 The MMC controller on the Intel PXA is supported. To
1008 enable this define CONFIG_MMC. The MMC can be
1009 accessed from the boot prompt by mapping the device
1010 to physical memory similar to flash. Command line is
1011 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1012 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1014 - Journaling Flash filesystem support:
1015 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1016 CONFIG_JFFS2_NAND_DEV
1017 Define these for a default partition on a NAND device
1019 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1020 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1021 Define these for a default partition on a NOR device
1023 CONFIG_SYS_JFFS_CUSTOM_PART
1024 Define this to create an own partition. You have to provide a
1025 function struct part_info* jffs2_part_info(int part_num)
1027 If you define only one JFFS2 partition you may also want to
1028 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1029 to disable the command chpart. This is the default when you
1030 have not defined a custom partition
1035 Define this to enable standard (PC-Style) keyboard
1039 Standard PC keyboard driver with US (is default) and
1040 GERMAN key layout (switch via environment 'keymap=de') support.
1041 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1042 for cfb_console. Supports cursor blinking.
1047 Define this to enable video support (for output to
1050 CONFIG_VIDEO_CT69000
1052 Enable Chips & Technologies 69000 Video chip
1054 CONFIG_VIDEO_SMI_LYNXEM
1055 Enable Silicon Motion SMI 712/710/810 Video chip. The
1056 video output is selected via environment 'videoout'
1057 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1060 For the CT69000 and SMI_LYNXEM drivers, videomode is
1061 selected via environment 'videomode'. Two different ways
1063 - "videomode=num" 'num' is a standard LiLo mode numbers.
1064 Following standard modes are supported (* is default):
1066 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1067 -------------+---------------------------------------------
1068 8 bits | 0x301* 0x303 0x305 0x161 0x307
1069 15 bits | 0x310 0x313 0x316 0x162 0x319
1070 16 bits | 0x311 0x314 0x317 0x163 0x31A
1071 24 bits | 0x312 0x315 0x318 ? 0x31B
1072 -------------+---------------------------------------------
1073 (i.e. setenv videomode 317; saveenv; reset;)
1075 - "videomode=bootargs" all the video parameters are parsed
1076 from the bootargs. (See drivers/video/videomodes.c)
1079 CONFIG_VIDEO_SED13806
1080 Enable Epson SED13806 driver. This driver supports 8bpp
1081 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1082 or CONFIG_VIDEO_SED13806_16BPP
1085 Enable the Freescale DIU video driver. Reference boards for
1086 SOCs that have a DIU should define this macro to enable DIU
1087 support, and should also define these other macros:
1093 CONFIG_VIDEO_SW_CURSOR
1094 CONFIG_VGA_AS_SINGLE_DEVICE
1096 CONFIG_VIDEO_BMP_LOGO
1098 The DIU driver will look for the 'monitor' environment variable,
1099 and if defined, enable the DIU as a console during boot. This
1100 variable should be set to one of these values:
1102 '0' Output video to the DVI connector
1103 '1' Output video to the LVDS connector
1104 '2' Output video to the Dual-Link LVDS connector
1109 Define this to enable a custom keyboard support.
1110 This simply calls drv_keyboard_init() which must be
1111 defined in your board-specific files.
1112 The only board using this so far is RBC823.
1114 - LCD Support: CONFIG_LCD
1116 Define this to enable LCD support (for output to LCD
1117 display); also select one of the supported displays
1118 by defining one of these:
1122 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1124 CONFIG_NEC_NL6448AC33:
1126 NEC NL6448AC33-18. Active, color, single scan.
1128 CONFIG_NEC_NL6448BC20
1130 NEC NL6448BC20-08. 6.5", 640x480.
1131 Active, color, single scan.
1133 CONFIG_NEC_NL6448BC33_54
1135 NEC NL6448BC33-54. 10.4", 640x480.
1136 Active, color, single scan.
1140 Sharp 320x240. Active, color, single scan.
1141 It isn't 16x9, and I am not sure what it is.
1143 CONFIG_SHARP_LQ64D341
1145 Sharp LQ64D341 display, 640x480.
1146 Active, color, single scan.
1150 HLD1045 display, 640x480.
1151 Active, color, single scan.
1155 Optrex CBL50840-2 NF-FW 99 22 M5
1157 Hitachi LMG6912RPFC-00T
1161 320x240. Black & white.
1163 Normally display is black on white background; define
1164 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1166 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1168 If this option is set, the environment is checked for
1169 a variable "splashimage". If found, the usual display
1170 of logo, copyright and system information on the LCD
1171 is suppressed and the BMP image at the address
1172 specified in "splashimage" is loaded instead. The
1173 console is redirected to the "nulldev", too. This
1174 allows for a "silent" boot where a splash screen is
1175 loaded very quickly after power-on.
1177 CONFIG_SPLASH_SCREEN_ALIGN
1179 If this option is set the splash image can be freely positioned
1180 on the screen. Environment variable "splashpos" specifies the
1181 position as "x,y". If a positive number is given it is used as
1182 number of pixel from left/top. If a negative number is given it
1183 is used as number of pixel from right/bottom. You can also
1184 specify 'm' for centering the image.
1187 setenv splashpos m,m
1188 => image at center of screen
1190 setenv splashpos 30,20
1191 => image at x = 30 and y = 20
1193 setenv splashpos -10,m
1194 => vertically centered image
1195 at x = dspWidth - bmpWidth - 9
1197 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1199 If this option is set, additionally to standard BMP
1200 images, gzipped BMP images can be displayed via the
1201 splashscreen support or the bmp command.
1203 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1205 If this option is set, 8-bit RLE compressed BMP images
1206 can be displayed via the splashscreen support or the
1209 - Compression support:
1212 If this option is set, support for bzip2 compressed
1213 images is included. If not, only uncompressed and gzip
1214 compressed images are supported.
1216 NOTE: the bzip2 algorithm requires a lot of RAM, so
1217 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1222 If this option is set, support for lzma compressed
1225 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1226 requires an amount of dynamic memory that is given by the
1229 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1231 Where lc and lp stand for, respectively, Literal context bits
1232 and Literal pos bits.
1234 This value is upper-bounded by 14MB in the worst case. Anyway,
1235 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1236 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1237 a very small buffer.
1239 Use the lzmainfo tool to determinate the lc and lp values and
1240 then calculate the amount of needed dynamic memory (ensuring
1241 the appropriate CONFIG_SYS_MALLOC_LEN value).
1246 The address of PHY on MII bus.
1248 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1250 The clock frequency of the MII bus
1254 If this option is set, support for speed/duplex
1255 detection of gigabit PHY is included.
1257 CONFIG_PHY_RESET_DELAY
1259 Some PHY like Intel LXT971A need extra delay after
1260 reset before any MII register access is possible.
1261 For such PHY, set this option to the usec delay
1262 required. (minimum 300usec for LXT971A)
1264 CONFIG_PHY_CMD_DELAY (ppc4xx)
1266 Some PHY like Intel LXT971A need extra delay after
1267 command issued before MII status register can be read
1277 Define a default value for Ethernet address to use
1278 for the respective Ethernet interface, in case this
1279 is not determined automatically.
1284 Define a default value for the IP address to use for
1285 the default Ethernet interface, in case this is not
1286 determined through e.g. bootp.
1288 - Server IP address:
1291 Defines a default value for the IP address of a TFTP
1292 server to contact when using the "tftboot" command.
1294 CONFIG_KEEP_SERVERADDR
1296 Keeps the server's MAC address, in the env 'serveraddr'
1297 for passing to bootargs (like Linux's netconsole option)
1299 - Multicast TFTP Mode:
1302 Defines whether you want to support multicast TFTP as per
1303 rfc-2090; for example to work with atftp. Lets lots of targets
1304 tftp down the same boot image concurrently. Note: the Ethernet
1305 driver in use must provide a function: mcast() to join/leave a
1308 CONFIG_BOOTP_RANDOM_DELAY
1309 - BOOTP Recovery Mode:
1310 CONFIG_BOOTP_RANDOM_DELAY
1312 If you have many targets in a network that try to
1313 boot using BOOTP, you may want to avoid that all
1314 systems send out BOOTP requests at precisely the same
1315 moment (which would happen for instance at recovery
1316 from a power failure, when all systems will try to
1317 boot, thus flooding the BOOTP server. Defining
1318 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1319 inserted before sending out BOOTP requests. The
1320 following delays are inserted then:
1322 1st BOOTP request: delay 0 ... 1 sec
1323 2nd BOOTP request: delay 0 ... 2 sec
1324 3rd BOOTP request: delay 0 ... 4 sec
1326 BOOTP requests: delay 0 ... 8 sec
1328 - DHCP Advanced Options:
1329 You can fine tune the DHCP functionality by defining
1330 CONFIG_BOOTP_* symbols:
1332 CONFIG_BOOTP_SUBNETMASK
1333 CONFIG_BOOTP_GATEWAY
1334 CONFIG_BOOTP_HOSTNAME
1335 CONFIG_BOOTP_NISDOMAIN
1336 CONFIG_BOOTP_BOOTPATH
1337 CONFIG_BOOTP_BOOTFILESIZE
1340 CONFIG_BOOTP_SEND_HOSTNAME
1341 CONFIG_BOOTP_NTPSERVER
1342 CONFIG_BOOTP_TIMEOFFSET
1343 CONFIG_BOOTP_VENDOREX
1345 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1346 environment variable, not the BOOTP server.
1348 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1349 serverip from a DHCP server, it is possible that more
1350 than one DNS serverip is offered to the client.
1351 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1352 serverip will be stored in the additional environment
1353 variable "dnsip2". The first DNS serverip is always
1354 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1357 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1358 to do a dynamic update of a DNS server. To do this, they
1359 need the hostname of the DHCP requester.
1360 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1361 of the "hostname" environment variable is passed as
1362 option 12 to the DHCP server.
1364 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1366 A 32bit value in microseconds for a delay between
1367 receiving a "DHCP Offer" and sending the "DHCP Request".
1368 This fixes a problem with certain DHCP servers that don't
1369 respond 100% of the time to a "DHCP request". E.g. On an
1370 AT91RM9200 processor running at 180MHz, this delay needed
1371 to be *at least* 15,000 usec before a Windows Server 2003
1372 DHCP server would reply 100% of the time. I recommend at
1373 least 50,000 usec to be safe. The alternative is to hope
1374 that one of the retries will be successful but note that
1375 the DHCP timeout and retry process takes a longer than
1379 CONFIG_CDP_DEVICE_ID
1381 The device id used in CDP trigger frames.
1383 CONFIG_CDP_DEVICE_ID_PREFIX
1385 A two character string which is prefixed to the MAC address
1390 A printf format string which contains the ascii name of
1391 the port. Normally is set to "eth%d" which sets
1392 eth0 for the first Ethernet, eth1 for the second etc.
1394 CONFIG_CDP_CAPABILITIES
1396 A 32bit integer which indicates the device capabilities;
1397 0x00000010 for a normal host which does not forwards.
1401 An ascii string containing the version of the software.
1405 An ascii string containing the name of the platform.
1409 A 32bit integer sent on the trigger.
1411 CONFIG_CDP_POWER_CONSUMPTION
1413 A 16bit integer containing the power consumption of the
1414 device in .1 of milliwatts.
1416 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1418 A byte containing the id of the VLAN.
1420 - Status LED: CONFIG_STATUS_LED
1422 Several configurations allow to display the current
1423 status using a LED. For instance, the LED will blink
1424 fast while running U-Boot code, stop blinking as
1425 soon as a reply to a BOOTP request was received, and
1426 start blinking slow once the Linux kernel is running
1427 (supported by a status LED driver in the Linux
1428 kernel). Defining CONFIG_STATUS_LED enables this
1431 - CAN Support: CONFIG_CAN_DRIVER
1433 Defining CONFIG_CAN_DRIVER enables CAN driver support
1434 on those systems that support this (optional)
1435 feature, like the TQM8xxL modules.
1437 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1439 These enable I2C serial bus commands. Defining either of
1440 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1441 include the appropriate I2C driver for the selected CPU.
1443 This will allow you to use i2c commands at the u-boot
1444 command line (as long as you set CONFIG_CMD_I2C in
1445 CONFIG_COMMANDS) and communicate with i2c based realtime
1446 clock chips. See common/cmd_i2c.c for a description of the
1447 command line interface.
1449 CONFIG_HARD_I2C selects a hardware I2C controller.
1451 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1452 bit-banging) driver instead of CPM or similar hardware
1455 There are several other quantities that must also be
1456 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1458 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1459 to be the frequency (in Hz) at which you wish your i2c bus
1460 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1461 the CPU's i2c node address).
1463 Now, the u-boot i2c code for the mpc8xx
1464 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1465 and so its address should therefore be cleared to 0 (See,
1466 eg, MPC823e User's Manual p.16-473). So, set
1467 CONFIG_SYS_I2C_SLAVE to 0.
1469 CONFIG_SYS_I2C_INIT_MPC5XXX
1471 When a board is reset during an i2c bus transfer
1472 chips might think that the current transfer is still
1473 in progress. Reset the slave devices by sending start
1474 commands until the slave device responds.
1476 That's all that's required for CONFIG_HARD_I2C.
1478 If you use the software i2c interface (CONFIG_SOFT_I2C)
1479 then the following macros need to be defined (examples are
1480 from include/configs/lwmon.h):
1484 (Optional). Any commands necessary to enable the I2C
1485 controller or configure ports.
1487 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1491 (Only for MPC8260 CPU). The I/O port to use (the code
1492 assumes both bits are on the same port). Valid values
1493 are 0..3 for ports A..D.
1497 The code necessary to make the I2C data line active
1498 (driven). If the data line is open collector, this
1501 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1505 The code necessary to make the I2C data line tri-stated
1506 (inactive). If the data line is open collector, this
1509 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1513 Code that returns TRUE if the I2C data line is high,
1516 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1520 If <bit> is TRUE, sets the I2C data line high. If it
1521 is FALSE, it clears it (low).
1523 eg: #define I2C_SDA(bit) \
1524 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1525 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1529 If <bit> is TRUE, sets the I2C clock line high. If it
1530 is FALSE, it clears it (low).
1532 eg: #define I2C_SCL(bit) \
1533 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1534 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1538 This delay is invoked four times per clock cycle so this
1539 controls the rate of data transfer. The data rate thus
1540 is 1 / (I2C_DELAY * 4). Often defined to be something
1543 #define I2C_DELAY udelay(2)
1545 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1547 If your arch supports the generic GPIO framework (asm/gpio.h),
1548 then you may alternatively define the two GPIOs that are to be
1549 used as SCL / SDA. Any of the previous I2C_xxx macros will
1550 have GPIO-based defaults assigned to them as appropriate.
1552 You should define these to the GPIO value as given directly to
1553 the generic GPIO functions.
1555 CONFIG_SYS_I2C_INIT_BOARD
1557 When a board is reset during an i2c bus transfer
1558 chips might think that the current transfer is still
1559 in progress. On some boards it is possible to access
1560 the i2c SCLK line directly, either by using the
1561 processor pin as a GPIO or by having a second pin
1562 connected to the bus. If this option is defined a
1563 custom i2c_init_board() routine in boards/xxx/board.c
1564 is run early in the boot sequence.
1566 CONFIG_SYS_I2C_BOARD_LATE_INIT
1568 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1569 defined a custom i2c_board_late_init() routine in
1570 boards/xxx/board.c is run AFTER the operations in i2c_init()
1571 is completed. This callpoint can be used to unreset i2c bus
1572 using CPU i2c controller register accesses for CPUs whose i2c
1573 controller provide such a method. It is called at the end of
1574 i2c_init() to allow i2c_init operations to setup the i2c bus
1575 controller on the CPU (e.g. setting bus speed & slave address).
1577 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1579 This option enables configuration of bi_iic_fast[] flags
1580 in u-boot bd_info structure based on u-boot environment
1581 variable "i2cfast". (see also i2cfast)
1583 CONFIG_I2C_MULTI_BUS
1585 This option allows the use of multiple I2C buses, each of which
1586 must have a controller. At any point in time, only one bus is
1587 active. To switch to a different bus, use the 'i2c dev' command.
1588 Note that bus numbering is zero-based.
1590 CONFIG_SYS_I2C_NOPROBES
1592 This option specifies a list of I2C devices that will be skipped
1593 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1594 is set, specify a list of bus-device pairs. Otherwise, specify
1595 a 1D array of device addresses
1598 #undef CONFIG_I2C_MULTI_BUS
1599 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1601 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1603 #define CONFIG_I2C_MULTI_BUS
1604 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1606 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1608 CONFIG_SYS_SPD_BUS_NUM
1610 If defined, then this indicates the I2C bus number for DDR SPD.
1611 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1613 CONFIG_SYS_RTC_BUS_NUM
1615 If defined, then this indicates the I2C bus number for the RTC.
1616 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1618 CONFIG_SYS_DTT_BUS_NUM
1620 If defined, then this indicates the I2C bus number for the DTT.
1621 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1623 CONFIG_SYS_I2C_DTT_ADDR:
1625 If defined, specifies the I2C address of the DTT device.
1626 If not defined, then U-Boot uses predefined value for
1627 specified DTT device.
1631 Define this option if you want to use Freescale's I2C driver in
1632 drivers/i2c/fsl_i2c.c.
1636 Define this option if you have I2C devices reached over 1 .. n
1637 I2C Muxes like the pca9544a. This option addes a new I2C
1638 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1639 new I2C Bus to the existing I2C Busses. If you select the
1640 new Bus with "i2c dev", u-bbot sends first the commandos for
1641 the muxes to activate this new "bus".
1643 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1647 Adding a new I2C Bus reached over 2 pca9544a muxes
1648 The First mux with address 70 and channel 6
1649 The Second mux with address 71 and channel 4
1651 => i2c bus pca9544a:70:6:pca9544a:71:4
1653 Use the "i2c bus" command without parameter, to get a list
1654 of I2C Busses with muxes:
1657 Busses reached over muxes:
1659 reached over Mux(es):
1662 reached over Mux(es):
1667 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1668 u-boot sends First the Commando to the mux@70 to enable
1669 channel 6, and then the Commando to the mux@71 to enable
1672 After that, you can use the "normal" i2c commands as
1673 usual, to communicate with your I2C devices behind
1676 This option is actually implemented for the bitbanging
1677 algorithm in common/soft_i2c.c and for the Hardware I2C
1678 Bus on the MPC8260. But it should be not so difficult
1679 to add this option to other architectures.
1681 CONFIG_SOFT_I2C_READ_REPEATED_START
1683 defining this will force the i2c_read() function in
1684 the soft_i2c driver to perform an I2C repeated start
1685 between writing the address pointer and reading the
1686 data. If this define is omitted the default behaviour
1687 of doing a stop-start sequence will be used. Most I2C
1688 devices can use either method, but some require one or
1691 - SPI Support: CONFIG_SPI
1693 Enables SPI driver (so far only tested with
1694 SPI EEPROM, also an instance works with Crystal A/D and
1695 D/As on the SACSng board)
1699 Enables the driver for SPI controller on SuperH. Currently
1700 only SH7757 is supported.
1704 Enables extended (16-bit) SPI EEPROM addressing.
1705 (symmetrical to CONFIG_I2C_X)
1709 Enables a software (bit-bang) SPI driver rather than
1710 using hardware support. This is a general purpose
1711 driver that only requires three general I/O port pins
1712 (two outputs, one input) to function. If this is
1713 defined, the board configuration must define several
1714 SPI configuration items (port pins to use, etc). For
1715 an example, see include/configs/sacsng.h.
1719 Enables a hardware SPI driver for general-purpose reads
1720 and writes. As with CONFIG_SOFT_SPI, the board configuration
1721 must define a list of chip-select function pointers.
1722 Currently supported on some MPC8xxx processors. For an
1723 example, see include/configs/mpc8349emds.h.
1727 Enables the driver for the SPI controllers on i.MX and MXC
1728 SoCs. Currently only i.MX31 is supported.
1730 - FPGA Support: CONFIG_FPGA
1732 Enables FPGA subsystem.
1734 CONFIG_FPGA_<vendor>
1736 Enables support for specific chip vendors.
1739 CONFIG_FPGA_<family>
1741 Enables support for FPGA family.
1742 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1746 Specify the number of FPGA devices to support.
1748 CONFIG_SYS_FPGA_PROG_FEEDBACK
1750 Enable printing of hash marks during FPGA configuration.
1752 CONFIG_SYS_FPGA_CHECK_BUSY
1754 Enable checks on FPGA configuration interface busy
1755 status by the configuration function. This option
1756 will require a board or device specific function to
1761 If defined, a function that provides delays in the FPGA
1762 configuration driver.
1764 CONFIG_SYS_FPGA_CHECK_CTRLC
1765 Allow Control-C to interrupt FPGA configuration
1767 CONFIG_SYS_FPGA_CHECK_ERROR
1769 Check for configuration errors during FPGA bitfile
1770 loading. For example, abort during Virtex II
1771 configuration if the INIT_B line goes low (which
1772 indicated a CRC error).
1774 CONFIG_SYS_FPGA_WAIT_INIT
1776 Maximum time to wait for the INIT_B line to deassert
1777 after PROB_B has been deasserted during a Virtex II
1778 FPGA configuration sequence. The default time is 500
1781 CONFIG_SYS_FPGA_WAIT_BUSY
1783 Maximum time to wait for BUSY to deassert during
1784 Virtex II FPGA configuration. The default is 5 ms.
1786 CONFIG_SYS_FPGA_WAIT_CONFIG
1788 Time to wait after FPGA configuration. The default is
1791 - Configuration Management:
1794 If defined, this string will be added to the U-Boot
1795 version information (U_BOOT_VERSION)
1797 - Vendor Parameter Protection:
1799 U-Boot considers the values of the environment
1800 variables "serial#" (Board Serial Number) and
1801 "ethaddr" (Ethernet Address) to be parameters that
1802 are set once by the board vendor / manufacturer, and
1803 protects these variables from casual modification by
1804 the user. Once set, these variables are read-only,
1805 and write or delete attempts are rejected. You can
1806 change this behaviour:
1808 If CONFIG_ENV_OVERWRITE is #defined in your config
1809 file, the write protection for vendor parameters is
1810 completely disabled. Anybody can change or delete
1813 Alternatively, if you #define _both_ CONFIG_ETHADDR
1814 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1815 Ethernet address is installed in the environment,
1816 which can be changed exactly ONCE by the user. [The
1817 serial# is unaffected by this, i. e. it remains
1823 Define this variable to enable the reservation of
1824 "protected RAM", i. e. RAM which is not overwritten
1825 by U-Boot. Define CONFIG_PRAM to hold the number of
1826 kB you want to reserve for pRAM. You can overwrite
1827 this default value by defining an environment
1828 variable "pram" to the number of kB you want to
1829 reserve. Note that the board info structure will
1830 still show the full amount of RAM. If pRAM is
1831 reserved, a new environment variable "mem" will
1832 automatically be defined to hold the amount of
1833 remaining RAM in a form that can be passed as boot
1834 argument to Linux, for instance like that:
1836 setenv bootargs ... mem=\${mem}
1839 This way you can tell Linux not to use this memory,
1840 either, which results in a memory region that will
1841 not be affected by reboots.
1843 *WARNING* If your board configuration uses automatic
1844 detection of the RAM size, you must make sure that
1845 this memory test is non-destructive. So far, the
1846 following board configurations are known to be
1849 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1850 HERMES, IP860, RPXlite, LWMON, LANTEC,
1856 Define this variable to stop the system in case of a
1857 fatal error, so that you have to reset it manually.
1858 This is probably NOT a good idea for an embedded
1859 system where you want the system to reboot
1860 automatically as fast as possible, but it may be
1861 useful during development since you can try to debug
1862 the conditions that lead to the situation.
1864 CONFIG_NET_RETRY_COUNT
1866 This variable defines the number of retries for
1867 network operations like ARP, RARP, TFTP, or BOOTP
1868 before giving up the operation. If not defined, a
1869 default value of 5 is used.
1873 Timeout waiting for an ARP reply in milliseconds.
1875 - Command Interpreter:
1876 CONFIG_AUTO_COMPLETE
1878 Enable auto completion of commands using TAB.
1880 Note that this feature has NOT been implemented yet
1881 for the "hush" shell.
1884 CONFIG_SYS_HUSH_PARSER
1886 Define this variable to enable the "hush" shell (from
1887 Busybox) as command line interpreter, thus enabling
1888 powerful command line syntax like
1889 if...then...else...fi conditionals or `&&' and '||'
1890 constructs ("shell scripts").
1892 If undefined, you get the old, much simpler behaviour
1893 with a somewhat smaller memory footprint.
1896 CONFIG_SYS_PROMPT_HUSH_PS2
1898 This defines the secondary prompt string, which is
1899 printed when the command interpreter needs more input
1900 to complete a command. Usually "> ".
1904 In the current implementation, the local variables
1905 space and global environment variables space are
1906 separated. Local variables are those you define by
1907 simply typing `name=value'. To access a local
1908 variable later on, you have write `$name' or
1909 `${name}'; to execute the contents of a variable
1910 directly type `$name' at the command prompt.
1912 Global environment variables are those you use
1913 setenv/printenv to work with. To run a command stored
1914 in such a variable, you need to use the run command,
1915 and you must not use the '$' sign to access them.
1917 To store commands and special characters in a
1918 variable, please use double quotation marks
1919 surrounding the whole text of the variable, instead
1920 of the backslashes before semicolons and special
1923 - Commandline Editing and History:
1924 CONFIG_CMDLINE_EDITING
1926 Enable editing and History functions for interactive
1927 commandline input operations
1929 - Default Environment:
1930 CONFIG_EXTRA_ENV_SETTINGS
1932 Define this to contain any number of null terminated
1933 strings (variable = value pairs) that will be part of
1934 the default environment compiled into the boot image.
1936 For example, place something like this in your
1937 board's config file:
1939 #define CONFIG_EXTRA_ENV_SETTINGS \
1943 Warning: This method is based on knowledge about the
1944 internal format how the environment is stored by the
1945 U-Boot code. This is NOT an official, exported
1946 interface! Although it is unlikely that this format
1947 will change soon, there is no guarantee either.
1948 You better know what you are doing here.
1950 Note: overly (ab)use of the default environment is
1951 discouraged. Make sure to check other ways to preset
1952 the environment like the "source" command or the
1955 - DataFlash Support:
1956 CONFIG_HAS_DATAFLASH
1958 Defining this option enables DataFlash features and
1959 allows to read/write in Dataflash via the standard
1962 - SystemACE Support:
1965 Adding this option adds support for Xilinx SystemACE
1966 chips attached via some sort of local bus. The address
1967 of the chip must also be defined in the
1968 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1970 #define CONFIG_SYSTEMACE
1971 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
1973 When SystemACE support is added, the "ace" device type
1974 becomes available to the fat commands, i.e. fatls.
1976 - TFTP Fixed UDP Port:
1979 If this is defined, the environment variable tftpsrcp
1980 is used to supply the TFTP UDP source port value.
1981 If tftpsrcp isn't defined, the normal pseudo-random port
1982 number generator is used.
1984 Also, the environment variable tftpdstp is used to supply
1985 the TFTP UDP destination port value. If tftpdstp isn't
1986 defined, the normal port 69 is used.
1988 The purpose for tftpsrcp is to allow a TFTP server to
1989 blindly start the TFTP transfer using the pre-configured
1990 target IP address and UDP port. This has the effect of
1991 "punching through" the (Windows XP) firewall, allowing
1992 the remainder of the TFTP transfer to proceed normally.
1993 A better solution is to properly configure the firewall,
1994 but sometimes that is not allowed.
1996 - Show boot progress:
1997 CONFIG_SHOW_BOOT_PROGRESS
1999 Defining this option allows to add some board-
2000 specific code (calling a user-provided function
2001 "show_boot_progress(int)") that enables you to show
2002 the system's boot progress on some display (for
2003 example, some LED's) on your board. At the moment,
2004 the following checkpoints are implemented:
2006 - Standalone program support:
2007 CONFIG_STANDALONE_LOAD_ADDR
2009 This option allows to define board specific values
2010 for the address where standalone program gets loaded,
2011 thus overwriting the architecutre dependent default
2014 - Frame Buffer Address:
2017 Define CONFIG_FB_ADDR if you want to use specific address for
2019 Then system will reserve the frame buffer address to defined address
2020 instead of lcd_setmem (this function grab the memory for frame buffer
2023 Please see board_init_f function.
2025 If you want this config option then,
2026 please define it at your board config file
2028 Legacy uImage format:
2031 1 common/cmd_bootm.c before attempting to boot an image
2032 -1 common/cmd_bootm.c Image header has bad magic number
2033 2 common/cmd_bootm.c Image header has correct magic number
2034 -2 common/cmd_bootm.c Image header has bad checksum
2035 3 common/cmd_bootm.c Image header has correct checksum
2036 -3 common/cmd_bootm.c Image data has bad checksum
2037 4 common/cmd_bootm.c Image data has correct checksum
2038 -4 common/cmd_bootm.c Image is for unsupported architecture
2039 5 common/cmd_bootm.c Architecture check OK
2040 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2041 6 common/cmd_bootm.c Image Type check OK
2042 -6 common/cmd_bootm.c gunzip uncompression error
2043 -7 common/cmd_bootm.c Unimplemented compression type
2044 7 common/cmd_bootm.c Uncompression OK
2045 8 common/cmd_bootm.c No uncompress/copy overwrite error
2046 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2048 9 common/image.c Start initial ramdisk verification
2049 -10 common/image.c Ramdisk header has bad magic number
2050 -11 common/image.c Ramdisk header has bad checksum
2051 10 common/image.c Ramdisk header is OK
2052 -12 common/image.c Ramdisk data has bad checksum
2053 11 common/image.c Ramdisk data has correct checksum
2054 12 common/image.c Ramdisk verification complete, start loading
2055 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2056 13 common/image.c Start multifile image verification
2057 14 common/image.c No initial ramdisk, no multifile, continue.
2059 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2061 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2062 -31 post/post.c POST test failed, detected by post_output_backlog()
2063 -32 post/post.c POST test failed, detected by post_run_single()
2065 34 common/cmd_doc.c before loading a Image from a DOC device
2066 -35 common/cmd_doc.c Bad usage of "doc" command
2067 35 common/cmd_doc.c correct usage of "doc" command
2068 -36 common/cmd_doc.c No boot device
2069 36 common/cmd_doc.c correct boot device
2070 -37 common/cmd_doc.c Unknown Chip ID on boot device
2071 37 common/cmd_doc.c correct chip ID found, device available
2072 -38 common/cmd_doc.c Read Error on boot device
2073 38 common/cmd_doc.c reading Image header from DOC device OK
2074 -39 common/cmd_doc.c Image header has bad magic number
2075 39 common/cmd_doc.c Image header has correct magic number
2076 -40 common/cmd_doc.c Error reading Image from DOC device
2077 40 common/cmd_doc.c Image header has correct magic number
2078 41 common/cmd_ide.c before loading a Image from a IDE device
2079 -42 common/cmd_ide.c Bad usage of "ide" command
2080 42 common/cmd_ide.c correct usage of "ide" command
2081 -43 common/cmd_ide.c No boot device
2082 43 common/cmd_ide.c boot device found
2083 -44 common/cmd_ide.c Device not available
2084 44 common/cmd_ide.c Device available
2085 -45 common/cmd_ide.c wrong partition selected
2086 45 common/cmd_ide.c partition selected
2087 -46 common/cmd_ide.c Unknown partition table
2088 46 common/cmd_ide.c valid partition table found
2089 -47 common/cmd_ide.c Invalid partition type
2090 47 common/cmd_ide.c correct partition type
2091 -48 common/cmd_ide.c Error reading Image Header on boot device
2092 48 common/cmd_ide.c reading Image Header from IDE device OK
2093 -49 common/cmd_ide.c Image header has bad magic number
2094 49 common/cmd_ide.c Image header has correct magic number
2095 -50 common/cmd_ide.c Image header has bad checksum
2096 50 common/cmd_ide.c Image header has correct checksum
2097 -51 common/cmd_ide.c Error reading Image from IDE device
2098 51 common/cmd_ide.c reading Image from IDE device OK
2099 52 common/cmd_nand.c before loading a Image from a NAND device
2100 -53 common/cmd_nand.c Bad usage of "nand" command
2101 53 common/cmd_nand.c correct usage of "nand" command
2102 -54 common/cmd_nand.c No boot device
2103 54 common/cmd_nand.c boot device found
2104 -55 common/cmd_nand.c Unknown Chip ID on boot device
2105 55 common/cmd_nand.c correct chip ID found, device available
2106 -56 common/cmd_nand.c Error reading Image Header on boot device
2107 56 common/cmd_nand.c reading Image Header from NAND device OK
2108 -57 common/cmd_nand.c Image header has bad magic number
2109 57 common/cmd_nand.c Image header has correct magic number
2110 -58 common/cmd_nand.c Error reading Image from NAND device
2111 58 common/cmd_nand.c reading Image from NAND device OK
2113 -60 common/env_common.c Environment has a bad CRC, using default
2115 64 net/eth.c starting with Ethernet configuration.
2116 -64 net/eth.c no Ethernet found.
2117 65 net/eth.c Ethernet found.
2119 -80 common/cmd_net.c usage wrong
2120 80 common/cmd_net.c before calling NetLoop()
2121 -81 common/cmd_net.c some error in NetLoop() occurred
2122 81 common/cmd_net.c NetLoop() back without error
2123 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2124 82 common/cmd_net.c trying automatic boot
2125 83 common/cmd_net.c running "source" command
2126 -83 common/cmd_net.c some error in automatic boot or "source" command
2127 84 common/cmd_net.c end without errors
2132 100 common/cmd_bootm.c Kernel FIT Image has correct format
2133 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2134 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2135 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2136 102 common/cmd_bootm.c Kernel unit name specified
2137 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2138 103 common/cmd_bootm.c Found configuration node
2139 104 common/cmd_bootm.c Got kernel subimage node offset
2140 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2141 105 common/cmd_bootm.c Kernel subimage hash verification OK
2142 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2143 106 common/cmd_bootm.c Architecture check OK
2144 -106 common/cmd_bootm.c Kernel subimage has wrong type
2145 107 common/cmd_bootm.c Kernel subimage type OK
2146 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2147 108 common/cmd_bootm.c Got kernel subimage data/size
2148 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2149 -109 common/cmd_bootm.c Can't get kernel subimage type
2150 -110 common/cmd_bootm.c Can't get kernel subimage comp
2151 -111 common/cmd_bootm.c Can't get kernel subimage os
2152 -112 common/cmd_bootm.c Can't get kernel subimage load address
2153 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2155 120 common/image.c Start initial ramdisk verification
2156 -120 common/image.c Ramdisk FIT image has incorrect format
2157 121 common/image.c Ramdisk FIT image has correct format
2158 122 common/image.c No ramdisk subimage unit name, using configuration
2159 -122 common/image.c Can't get configuration for ramdisk subimage
2160 123 common/image.c Ramdisk unit name specified
2161 -124 common/image.c Can't get ramdisk subimage node offset
2162 125 common/image.c Got ramdisk subimage node offset
2163 -125 common/image.c Ramdisk subimage hash verification failed
2164 126 common/image.c Ramdisk subimage hash verification OK
2165 -126 common/image.c Ramdisk subimage for unsupported architecture
2166 127 common/image.c Architecture check OK
2167 -127 common/image.c Can't get ramdisk subimage data/size
2168 128 common/image.c Got ramdisk subimage data/size
2169 129 common/image.c Can't get ramdisk load address
2170 -129 common/image.c Got ramdisk load address
2172 -130 common/cmd_doc.c Incorrect FIT image format
2173 131 common/cmd_doc.c FIT image format OK
2175 -140 common/cmd_ide.c Incorrect FIT image format
2176 141 common/cmd_ide.c FIT image format OK
2178 -150 common/cmd_nand.c Incorrect FIT image format
2179 151 common/cmd_nand.c FIT image format OK
2181 - Automatic software updates via TFTP server
2183 CONFIG_UPDATE_TFTP_CNT_MAX
2184 CONFIG_UPDATE_TFTP_MSEC_MAX
2186 These options enable and control the auto-update feature;
2187 for a more detailed description refer to doc/README.update.
2189 - MTD Support (mtdparts command, UBI support)
2192 Adds the MTD device infrastructure from the Linux kernel.
2193 Needed for mtdparts command support.
2195 CONFIG_MTD_PARTITIONS
2197 Adds the MTD partitioning infrastructure from the Linux
2198 kernel. Needed for UBI support.
2204 [so far only for SMDK2400 and TRAB boards]
2206 - Modem support enable:
2207 CONFIG_MODEM_SUPPORT
2209 - RTS/CTS Flow control enable:
2212 - Modem debug support:
2213 CONFIG_MODEM_SUPPORT_DEBUG
2215 Enables debugging stuff (char screen[1024], dbg())
2216 for modem support. Useful only with BDI2000.
2218 - Interrupt support (PPC):
2220 There are common interrupt_init() and timer_interrupt()
2221 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2222 for CPU specific initialization. interrupt_init_cpu()
2223 should set decrementer_count to appropriate value. If
2224 CPU resets decrementer automatically after interrupt
2225 (ppc4xx) it should set decrementer_count to zero.
2226 timer_interrupt() calls timer_interrupt_cpu() for CPU
2227 specific handling. If board has watchdog / status_led
2228 / other_activity_monitor it works automatically from
2229 general timer_interrupt().
2233 In the target system modem support is enabled when a
2234 specific key (key combination) is pressed during
2235 power-on. Otherwise U-Boot will boot normally
2236 (autoboot). The key_pressed() function is called from
2237 board_init(). Currently key_pressed() is a dummy
2238 function, returning 1 and thus enabling modem
2241 If there are no modem init strings in the
2242 environment, U-Boot proceed to autoboot; the
2243 previous output (banner, info printfs) will be
2246 See also: doc/README.Modem
2249 Configuration Settings:
2250 -----------------------
2252 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2253 undefine this when you're short of memory.
2255 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2256 width of the commands listed in the 'help' command output.
2258 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2259 prompt for user input.
2261 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2263 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2265 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2267 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2268 the application (usually a Linux kernel) when it is
2271 - CONFIG_SYS_BAUDRATE_TABLE:
2272 List of legal baudrate settings for this board.
2274 - CONFIG_SYS_CONSOLE_INFO_QUIET
2275 Suppress display of console information at boot.
2277 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2278 If the board specific function
2279 extern int overwrite_console (void);
2280 returns 1, the stdin, stderr and stdout are switched to the
2281 serial port, else the settings in the environment are used.
2283 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2284 Enable the call to overwrite_console().
2286 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2287 Enable overwrite of previous console environment settings.
2289 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2290 Begin and End addresses of the area used by the
2293 - CONFIG_SYS_ALT_MEMTEST:
2294 Enable an alternate, more extensive memory test.
2296 - CONFIG_SYS_MEMTEST_SCRATCH:
2297 Scratch address used by the alternate memory test
2298 You only need to set this if address zero isn't writeable
2300 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2301 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2302 this specified memory area will get subtracted from the top
2303 (end) of RAM and won't get "touched" at all by U-Boot. By
2304 fixing up gd->ram_size the Linux kernel should gets passed
2305 the now "corrected" memory size and won't touch it either.
2306 This should work for arch/ppc and arch/powerpc. Only Linux
2307 board ports in arch/powerpc with bootwrapper support that
2308 recalculate the memory size from the SDRAM controller setup
2309 will have to get fixed in Linux additionally.
2311 This option can be used as a workaround for the 440EPx/GRx
2312 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2315 WARNING: Please make sure that this value is a multiple of
2316 the Linux page size (normally 4k). If this is not the case,
2317 then the end address of the Linux memory will be located at a
2318 non page size aligned address and this could cause major
2321 - CONFIG_SYS_TFTP_LOADADDR:
2322 Default load address for network file downloads
2324 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2325 Enable temporary baudrate change while serial download
2327 - CONFIG_SYS_SDRAM_BASE:
2328 Physical start address of SDRAM. _Must_ be 0 here.
2330 - CONFIG_SYS_MBIO_BASE:
2331 Physical start address of Motherboard I/O (if using a
2334 - CONFIG_SYS_FLASH_BASE:
2335 Physical start address of Flash memory.
2337 - CONFIG_SYS_MONITOR_BASE:
2338 Physical start address of boot monitor code (set by
2339 make config files to be same as the text base address
2340 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2341 CONFIG_SYS_FLASH_BASE when booting from flash.
2343 - CONFIG_SYS_MONITOR_LEN:
2344 Size of memory reserved for monitor code, used to
2345 determine _at_compile_time_ (!) if the environment is
2346 embedded within the U-Boot image, or in a separate
2349 - CONFIG_SYS_MALLOC_LEN:
2350 Size of DRAM reserved for malloc() use.
2352 - CONFIG_SYS_BOOTM_LEN:
2353 Normally compressed uImages are limited to an
2354 uncompressed size of 8 MBytes. If this is not enough,
2355 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2356 to adjust this setting to your needs.
2358 - CONFIG_SYS_BOOTMAPSZ:
2359 Maximum size of memory mapped by the startup code of
2360 the Linux kernel; all data that must be processed by
2361 the Linux kernel (bd_info, boot arguments, FDT blob if
2362 used) must be put below this limit, unless "bootm_low"
2363 enviroment variable is defined and non-zero. In such case
2364 all data for the Linux kernel must be between "bootm_low"
2365 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2366 variable "bootm_mapsize" will override the value of
2367 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2368 then the value in "bootm_size" will be used instead.
2370 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2371 Enable initrd_high functionality. If defined then the
2372 initrd_high feature is enabled and the bootm ramdisk subcommand
2375 - CONFIG_SYS_BOOT_GET_CMDLINE:
2376 Enables allocating and saving kernel cmdline in space between
2377 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2379 - CONFIG_SYS_BOOT_GET_KBD:
2380 Enables allocating and saving a kernel copy of the bd_info in
2381 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2383 - CONFIG_SYS_MAX_FLASH_BANKS:
2384 Max number of Flash memory banks
2386 - CONFIG_SYS_MAX_FLASH_SECT:
2387 Max number of sectors on a Flash chip
2389 - CONFIG_SYS_FLASH_ERASE_TOUT:
2390 Timeout for Flash erase operations (in ms)
2392 - CONFIG_SYS_FLASH_WRITE_TOUT:
2393 Timeout for Flash write operations (in ms)
2395 - CONFIG_SYS_FLASH_LOCK_TOUT
2396 Timeout for Flash set sector lock bit operation (in ms)
2398 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2399 Timeout for Flash clear lock bits operation (in ms)
2401 - CONFIG_SYS_FLASH_PROTECTION
2402 If defined, hardware flash sectors protection is used
2403 instead of U-Boot software protection.
2405 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2407 Enable TFTP transfers directly to flash memory;
2408 without this option such a download has to be
2409 performed in two steps: (1) download to RAM, and (2)
2410 copy from RAM to flash.
2412 The two-step approach is usually more reliable, since
2413 you can check if the download worked before you erase
2414 the flash, but in some situations (when system RAM is
2415 too limited to allow for a temporary copy of the
2416 downloaded image) this option may be very useful.
2418 - CONFIG_SYS_FLASH_CFI:
2419 Define if the flash driver uses extra elements in the
2420 common flash structure for storing flash geometry.
2422 - CONFIG_FLASH_CFI_DRIVER
2423 This option also enables the building of the cfi_flash driver
2424 in the drivers directory
2426 - CONFIG_FLASH_CFI_MTD
2427 This option enables the building of the cfi_mtd driver
2428 in the drivers directory. The driver exports CFI flash
2431 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2432 Use buffered writes to flash.
2434 - CONFIG_FLASH_SPANSION_S29WS_N
2435 s29ws-n MirrorBit flash has non-standard addresses for buffered
2438 - CONFIG_SYS_FLASH_QUIET_TEST
2439 If this option is defined, the common CFI flash doesn't
2440 print it's warning upon not recognized FLASH banks. This
2441 is useful, if some of the configured banks are only
2442 optionally available.
2444 - CONFIG_FLASH_SHOW_PROGRESS
2445 If defined (must be an integer), print out countdown
2446 digits and dots. Recommended value: 45 (9..1) for 80
2447 column displays, 15 (3..1) for 40 column displays.
2449 - CONFIG_SYS_RX_ETH_BUFFER:
2450 Defines the number of Ethernet receive buffers. On some
2451 Ethernet controllers it is recommended to set this value
2452 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2453 buffers can be full shortly after enabling the interface
2454 on high Ethernet traffic.
2455 Defaults to 4 if not defined.
2457 - CONFIG_ENV_MAX_ENTRIES
2459 Maximum number of entries in the hash table that is used
2460 internally to store the environment settings. The default
2461 setting is supposed to be generous and should work in most
2462 cases. This setting can be used to tune behaviour; see
2463 lib/hashtable.c for details.
2465 The following definitions that deal with the placement and management
2466 of environment data (variable area); in general, we support the
2467 following configurations:
2469 - CONFIG_ENV_IS_IN_FLASH:
2471 Define this if the environment is in flash memory.
2473 a) The environment occupies one whole flash sector, which is
2474 "embedded" in the text segment with the U-Boot code. This
2475 happens usually with "bottom boot sector" or "top boot
2476 sector" type flash chips, which have several smaller
2477 sectors at the start or the end. For instance, such a
2478 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2479 such a case you would place the environment in one of the
2480 4 kB sectors - with U-Boot code before and after it. With
2481 "top boot sector" type flash chips, you would put the
2482 environment in one of the last sectors, leaving a gap
2483 between U-Boot and the environment.
2485 - CONFIG_ENV_OFFSET:
2487 Offset of environment data (variable area) to the
2488 beginning of flash memory; for instance, with bottom boot
2489 type flash chips the second sector can be used: the offset
2490 for this sector is given here.
2492 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2496 This is just another way to specify the start address of
2497 the flash sector containing the environment (instead of
2500 - CONFIG_ENV_SECT_SIZE:
2502 Size of the sector containing the environment.
2505 b) Sometimes flash chips have few, equal sized, BIG sectors.
2506 In such a case you don't want to spend a whole sector for
2511 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2512 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2513 of this flash sector for the environment. This saves
2514 memory for the RAM copy of the environment.
2516 It may also save flash memory if you decide to use this
2517 when your environment is "embedded" within U-Boot code,
2518 since then the remainder of the flash sector could be used
2519 for U-Boot code. It should be pointed out that this is
2520 STRONGLY DISCOURAGED from a robustness point of view:
2521 updating the environment in flash makes it always
2522 necessary to erase the WHOLE sector. If something goes
2523 wrong before the contents has been restored from a copy in
2524 RAM, your target system will be dead.
2526 - CONFIG_ENV_ADDR_REDUND
2527 CONFIG_ENV_SIZE_REDUND
2529 These settings describe a second storage area used to hold
2530 a redundant copy of the environment data, so that there is
2531 a valid backup copy in case there is a power failure during
2532 a "saveenv" operation.
2534 BE CAREFUL! Any changes to the flash layout, and some changes to the
2535 source code will make it necessary to adapt <board>/u-boot.lds*
2539 - CONFIG_ENV_IS_IN_NVRAM:
2541 Define this if you have some non-volatile memory device
2542 (NVRAM, battery buffered SRAM) which you want to use for the
2548 These two #defines are used to determine the memory area you
2549 want to use for environment. It is assumed that this memory
2550 can just be read and written to, without any special
2553 BE CAREFUL! The first access to the environment happens quite early
2554 in U-Boot initalization (when we try to get the setting of for the
2555 console baudrate). You *MUST* have mapped your NVRAM area then, or
2558 Please note that even with NVRAM we still use a copy of the
2559 environment in RAM: we could work on NVRAM directly, but we want to
2560 keep settings there always unmodified except somebody uses "saveenv"
2561 to save the current settings.
2564 - CONFIG_ENV_IS_IN_EEPROM:
2566 Use this if you have an EEPROM or similar serial access
2567 device and a driver for it.
2569 - CONFIG_ENV_OFFSET:
2572 These two #defines specify the offset and size of the
2573 environment area within the total memory of your EEPROM.
2575 - CONFIG_SYS_I2C_EEPROM_ADDR:
2576 If defined, specified the chip address of the EEPROM device.
2577 The default address is zero.
2579 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2580 If defined, the number of bits used to address bytes in a
2581 single page in the EEPROM device. A 64 byte page, for example
2582 would require six bits.
2584 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2585 If defined, the number of milliseconds to delay between
2586 page writes. The default is zero milliseconds.
2588 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2589 The length in bytes of the EEPROM memory array address. Note
2590 that this is NOT the chip address length!
2592 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2593 EEPROM chips that implement "address overflow" are ones
2594 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2595 address and the extra bits end up in the "chip address" bit
2596 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2599 Note that we consider the length of the address field to
2600 still be one byte because the extra address bits are hidden
2601 in the chip address.
2603 - CONFIG_SYS_EEPROM_SIZE:
2604 The size in bytes of the EEPROM device.
2606 - CONFIG_ENV_EEPROM_IS_ON_I2C
2607 define this, if you have I2C and SPI activated, and your
2608 EEPROM, which holds the environment, is on the I2C bus.
2610 - CONFIG_I2C_ENV_EEPROM_BUS
2611 if you have an Environment on an EEPROM reached over
2612 I2C muxes, you can define here, how to reach this
2613 EEPROM. For example:
2615 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2617 EEPROM which holds the environment, is reached over
2618 a pca9547 i2c mux with address 0x70, channel 3.
2620 - CONFIG_ENV_IS_IN_DATAFLASH:
2622 Define this if you have a DataFlash memory device which you
2623 want to use for the environment.
2625 - CONFIG_ENV_OFFSET:
2629 These three #defines specify the offset and size of the
2630 environment area within the total memory of your DataFlash placed
2631 at the specified address.
2633 - CONFIG_ENV_IS_IN_NAND:
2635 Define this if you have a NAND device which you want to use
2636 for the environment.
2638 - CONFIG_ENV_OFFSET:
2641 These two #defines specify the offset and size of the environment
2642 area within the first NAND device. CONFIG_ENV_OFFSET must be
2643 aligned to an erase block boundary.
2645 - CONFIG_ENV_OFFSET_REDUND (optional):
2647 This setting describes a second storage area of CONFIG_ENV_SIZE
2648 size used to hold a redundant copy of the environment data, so
2649 that there is a valid backup copy in case there is a power failure
2650 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2651 aligned to an erase block boundary.
2653 - CONFIG_ENV_RANGE (optional):
2655 Specifies the length of the region in which the environment
2656 can be written. This should be a multiple of the NAND device's
2657 block size. Specifying a range with more erase blocks than
2658 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2659 the range to be avoided.
2661 - CONFIG_ENV_OFFSET_OOB (optional):
2663 Enables support for dynamically retrieving the offset of the
2664 environment from block zero's out-of-band data. The
2665 "nand env.oob" command can be used to record this offset.
2666 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2667 using CONFIG_ENV_OFFSET_OOB.
2669 - CONFIG_NAND_ENV_DST
2671 Defines address in RAM to which the nand_spl code should copy the
2672 environment. If redundant environment is used, it will be copied to
2673 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2675 - CONFIG_SYS_SPI_INIT_OFFSET
2677 Defines offset to the initial SPI buffer area in DPRAM. The
2678 area is used at an early stage (ROM part) if the environment
2679 is configured to reside in the SPI EEPROM: We need a 520 byte
2680 scratch DPRAM area. It is used between the two initialization
2681 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2682 to be a good choice since it makes it far enough from the
2683 start of the data area as well as from the stack pointer.
2685 Please note that the environment is read-only until the monitor
2686 has been relocated to RAM and a RAM copy of the environment has been
2687 created; also, when using EEPROM you will have to use getenv_f()
2688 until then to read environment variables.
2690 The environment is protected by a CRC32 checksum. Before the monitor
2691 is relocated into RAM, as a result of a bad CRC you will be working
2692 with the compiled-in default environment - *silently*!!! [This is
2693 necessary, because the first environment variable we need is the
2694 "baudrate" setting for the console - if we have a bad CRC, we don't
2695 have any device yet where we could complain.]
2697 Note: once the monitor has been relocated, then it will complain if
2698 the default environment is used; a new CRC is computed as soon as you
2699 use the "saveenv" command to store a valid environment.
2701 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2702 Echo the inverted Ethernet link state to the fault LED.
2704 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2705 also needs to be defined.
2707 - CONFIG_SYS_FAULT_MII_ADDR:
2708 MII address of the PHY to check for the Ethernet link state.
2710 - CONFIG_NS16550_MIN_FUNCTIONS:
2711 Define this if you desire to only have use of the NS16550_init
2712 and NS16550_putc functions for the serial driver located at
2713 drivers/serial/ns16550.c. This option is useful for saving
2714 space for already greatly restricted images, including but not
2715 limited to NAND_SPL configurations.
2717 Low Level (hardware related) configuration options:
2718 ---------------------------------------------------
2720 - CONFIG_SYS_CACHELINE_SIZE:
2721 Cache Line Size of the CPU.
2723 - CONFIG_SYS_DEFAULT_IMMR:
2724 Default address of the IMMR after system reset.
2726 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2727 and RPXsuper) to be able to adjust the position of
2728 the IMMR register after a reset.
2730 - Floppy Disk Support:
2731 CONFIG_SYS_FDC_DRIVE_NUMBER
2733 the default drive number (default value 0)
2735 CONFIG_SYS_ISA_IO_STRIDE
2737 defines the spacing between FDC chipset registers
2740 CONFIG_SYS_ISA_IO_OFFSET
2742 defines the offset of register from address. It
2743 depends on which part of the data bus is connected to
2744 the FDC chipset. (default value 0)
2746 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2747 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2750 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2751 fdc_hw_init() is called at the beginning of the FDC
2752 setup. fdc_hw_init() must be provided by the board
2753 source code. It is used to make hardware dependant
2756 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2757 DO NOT CHANGE unless you know exactly what you're
2758 doing! (11-4) [MPC8xx/82xx systems only]
2760 - CONFIG_SYS_INIT_RAM_ADDR:
2762 Start address of memory area that can be used for
2763 initial data and stack; please note that this must be
2764 writable memory that is working WITHOUT special
2765 initialization, i. e. you CANNOT use normal RAM which
2766 will become available only after programming the
2767 memory controller and running certain initialization
2770 U-Boot uses the following memory types:
2771 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2772 - MPC824X: data cache
2773 - PPC4xx: data cache
2775 - CONFIG_SYS_GBL_DATA_OFFSET:
2777 Offset of the initial data structure in the memory
2778 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2779 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2780 data is located at the end of the available space
2781 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2782 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2783 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2784 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2787 On the MPC824X (or other systems that use the data
2788 cache for initial memory) the address chosen for
2789 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2790 point to an otherwise UNUSED address space between
2791 the top of RAM and the start of the PCI space.
2793 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2795 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2797 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2799 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2801 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2803 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2805 - CONFIG_SYS_OR_TIMING_SDRAM:
2808 - CONFIG_SYS_MAMR_PTA:
2809 periodic timer for refresh
2811 - CONFIG_SYS_DER: Debug Event Register (37-47)
2813 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2814 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2815 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2816 CONFIG_SYS_BR1_PRELIM:
2817 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2819 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2820 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2821 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2822 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2824 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2825 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2826 Machine Mode Register and Memory Periodic Timer
2827 Prescaler definitions (SDRAM timing)
2829 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2830 enable I2C microcode relocation patch (MPC8xx);
2831 define relocation offset in DPRAM [DSP2]
2833 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2834 enable SMC microcode relocation patch (MPC8xx);
2835 define relocation offset in DPRAM [SMC1]
2837 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2838 enable SPI microcode relocation patch (MPC8xx);
2839 define relocation offset in DPRAM [SCC4]
2841 - CONFIG_SYS_USE_OSCCLK:
2842 Use OSCM clock mode on MBX8xx board. Be careful,
2843 wrong setting might damage your board. Read
2844 doc/README.MBX before setting this variable!
2846 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2847 Offset of the bootmode word in DPRAM used by post
2848 (Power On Self Tests). This definition overrides
2849 #define'd default value in commproc.h resp.
2852 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2853 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2854 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2855 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2856 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2857 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2858 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2859 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2860 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2862 - CONFIG_PCI_DISABLE_PCIE:
2863 Disable PCI-Express on systems where it is supported but not
2867 Chip has SRIO or not
2870 Board has SRIO 1 port available
2873 Board has SRIO 2 port available
2875 - CONFIG_SYS_SRIOn_MEM_VIRT:
2876 Virtual Address of SRIO port 'n' memory region
2878 - CONFIG_SYS_SRIOn_MEM_PHYS:
2879 Physical Address of SRIO port 'n' memory region
2881 - CONFIG_SYS_SRIOn_MEM_SIZE:
2882 Size of SRIO port 'n' memory region
2885 Get DDR timing information from an I2C EEPROM. Common
2886 with pluggable memory modules such as SODIMMs
2889 I2C address of the SPD EEPROM
2891 - CONFIG_SYS_SPD_BUS_NUM
2892 If SPD EEPROM is on an I2C bus other than the first
2893 one, specify here. Note that the value must resolve
2894 to something your driver can deal with.
2896 - CONFIG_SYS_83XX_DDR_USES_CS0
2897 Only for 83xx systems. If specified, then DDR should
2898 be configured using CS0 and CS1 instead of CS2 and CS3.
2900 - CONFIG_ETHER_ON_FEC[12]
2901 Define to enable FEC[12] on a 8xx series processor.
2903 - CONFIG_FEC[12]_PHY
2904 Define to the hardcoded PHY address which corresponds
2905 to the given FEC; i. e.
2906 #define CONFIG_FEC1_PHY 4
2907 means that the PHY with address 4 is connected to FEC1
2909 When set to -1, means to probe for first available.
2911 - CONFIG_FEC[12]_PHY_NORXERR
2912 The PHY does not have a RXERR line (RMII only).
2913 (so program the FEC to ignore it).
2916 Enable RMII mode for all FECs.
2917 Note that this is a global option, we can't
2918 have one FEC in standard MII mode and another in RMII mode.
2920 - CONFIG_CRC32_VERIFY
2921 Add a verify option to the crc32 command.
2924 => crc32 -v <address> <count> <crc32>
2926 Where address/count indicate a memory area
2927 and crc32 is the correct crc32 which the
2931 Add the "loopw" memory command. This only takes effect if
2932 the memory commands are activated globally (CONFIG_CMD_MEM).
2935 Add the "mdc" and "mwc" memory commands. These are cyclic
2940 This command will print 4 bytes (10,11,12,13) each 500 ms.
2942 => mwc.l 100 12345678 10
2943 This command will write 12345678 to address 100 all 10 ms.
2945 This only takes effect if the memory commands are activated
2946 globally (CONFIG_CMD_MEM).
2948 - CONFIG_SKIP_LOWLEVEL_INIT
2949 [ARM only] If this variable is defined, then certain
2950 low level initializations (like setting up the memory
2951 controller) are omitted and/or U-Boot does not
2952 relocate itself into RAM.
2954 Normally this variable MUST NOT be defined. The only
2955 exception is when U-Boot is loaded (to RAM) by some
2956 other boot loader or by a debugger which performs
2957 these initializations itself.
2960 Modifies the behaviour of start.S when compiling a loader
2961 that is executed before the actual U-Boot. E.g. when
2962 compiling a NAND SPL.
2964 - CONFIG_USE_ARCH_MEMCPY
2965 CONFIG_USE_ARCH_MEMSET
2966 If these options are used a optimized version of memcpy/memset will
2967 be used if available. These functions may be faster under some
2968 conditions but may increase the binary size.
2970 Building the Software:
2971 ======================
2973 Building U-Boot has been tested in several native build environments
2974 and in many different cross environments. Of course we cannot support
2975 all possibly existing versions of cross development tools in all
2976 (potentially obsolete) versions. In case of tool chain problems we
2977 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2978 which is extensively used to build and test U-Boot.
2980 If you are not using a native environment, it is assumed that you
2981 have GNU cross compiling tools available in your path. In this case,
2982 you must set the environment variable CROSS_COMPILE in your shell.
2983 Note that no changes to the Makefile or any other source files are
2984 necessary. For example using the ELDK on a 4xx CPU, please enter:
2986 $ CROSS_COMPILE=ppc_4xx-
2987 $ export CROSS_COMPILE
2989 Note: If you wish to generate Windows versions of the utilities in
2990 the tools directory you can use the MinGW toolchain
2991 (http://www.mingw.org). Set your HOST tools to the MinGW
2992 toolchain and execute 'make tools'. For example:
2994 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
2996 Binaries such as tools/mkimage.exe will be created which can
2997 be executed on computers running Windows.
2999 U-Boot is intended to be simple to build. After installing the
3000 sources you must configure U-Boot for one specific board type. This
3005 where "NAME_config" is the name of one of the existing configu-
3006 rations; see the main Makefile for supported names.
3008 Note: for some board special configuration names may exist; check if
3009 additional information is available from the board vendor; for
3010 instance, the TQM823L systems are available without (standard)
3011 or with LCD support. You can select such additional "features"
3012 when choosing the configuration, i. e.
3015 - will configure for a plain TQM823L, i. e. no LCD support
3017 make TQM823L_LCD_config
3018 - will configure for a TQM823L with U-Boot console on LCD
3023 Finally, type "make all", and you should get some working U-Boot
3024 images ready for download to / installation on your system:
3026 - "u-boot.bin" is a raw binary image
3027 - "u-boot" is an image in ELF binary format
3028 - "u-boot.srec" is in Motorola S-Record format
3030 By default the build is performed locally and the objects are saved
3031 in the source directory. One of the two methods can be used to change
3032 this behavior and build U-Boot to some external directory:
3034 1. Add O= to the make command line invocations:
3036 make O=/tmp/build distclean
3037 make O=/tmp/build NAME_config
3038 make O=/tmp/build all
3040 2. Set environment variable BUILD_DIR to point to the desired location:
3042 export BUILD_DIR=/tmp/build
3047 Note that the command line "O=" setting overrides the BUILD_DIR environment
3051 Please be aware that the Makefiles assume you are using GNU make, so
3052 for instance on NetBSD you might need to use "gmake" instead of
3056 If the system board that you have is not listed, then you will need
3057 to port U-Boot to your hardware platform. To do this, follow these
3060 1. Add a new configuration option for your board to the toplevel
3061 "Makefile" and to the "MAKEALL" script, using the existing
3062 entries as examples. Note that here and at many other places
3063 boards and other names are listed in alphabetical sort order. Please
3065 2. Create a new directory to hold your board specific code. Add any
3066 files you need. In your board directory, you will need at least
3067 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3068 3. Create a new configuration file "include/configs/<board>.h" for
3070 3. If you're porting U-Boot to a new CPU, then also create a new
3071 directory to hold your CPU specific code. Add any files you need.
3072 4. Run "make <board>_config" with your new name.
3073 5. Type "make", and you should get a working "u-boot.srec" file
3074 to be installed on your target system.
3075 6. Debug and solve any problems that might arise.
3076 [Of course, this last step is much harder than it sounds.]
3079 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3080 ==============================================================
3082 If you have modified U-Boot sources (for instance added a new board
3083 or support for new devices, a new CPU, etc.) you are expected to
3084 provide feedback to the other developers. The feedback normally takes
3085 the form of a "patch", i. e. a context diff against a certain (latest
3086 official or latest in the git repository) version of U-Boot sources.
3088 But before you submit such a patch, please verify that your modifi-
3089 cation did not break existing code. At least make sure that *ALL* of
3090 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3091 just run the "MAKEALL" script, which will configure and build U-Boot
3092 for ALL supported system. Be warned, this will take a while. You can
3093 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3094 environment variable to the script, i. e. to use the ELDK cross tools
3097 CROSS_COMPILE=ppc_8xx- MAKEALL
3099 or to build on a native PowerPC system you can type
3101 CROSS_COMPILE=' ' MAKEALL
3103 When using the MAKEALL script, the default behaviour is to build
3104 U-Boot in the source directory. This location can be changed by
3105 setting the BUILD_DIR environment variable. Also, for each target
3106 built, the MAKEALL script saves two log files (<target>.ERR and
3107 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3108 location can be changed by setting the MAKEALL_LOGDIR environment
3109 variable. For example:
3111 export BUILD_DIR=/tmp/build
3112 export MAKEALL_LOGDIR=/tmp/log
3113 CROSS_COMPILE=ppc_8xx- MAKEALL
3115 With the above settings build objects are saved in the /tmp/build,
3116 log files are saved in the /tmp/log and the source tree remains clean
3117 during the whole build process.
3120 See also "U-Boot Porting Guide" below.
3123 Monitor Commands - Overview:
3124 ============================
3126 go - start application at address 'addr'
3127 run - run commands in an environment variable
3128 bootm - boot application image from memory
3129 bootp - boot image via network using BootP/TFTP protocol
3130 tftpboot- boot image via network using TFTP protocol
3131 and env variables "ipaddr" and "serverip"
3132 (and eventually "gatewayip")
3133 rarpboot- boot image via network using RARP/TFTP protocol
3134 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3135 loads - load S-Record file over serial line
3136 loadb - load binary file over serial line (kermit mode)
3138 mm - memory modify (auto-incrementing)
3139 nm - memory modify (constant address)
3140 mw - memory write (fill)
3142 cmp - memory compare
3143 crc32 - checksum calculation
3144 i2c - I2C sub-system
3145 sspi - SPI utility commands
3146 base - print or set address offset
3147 printenv- print environment variables
3148 setenv - set environment variables
3149 saveenv - save environment variables to persistent storage
3150 protect - enable or disable FLASH write protection
3151 erase - erase FLASH memory
3152 flinfo - print FLASH memory information
3153 bdinfo - print Board Info structure
3154 iminfo - print header information for application image
3155 coninfo - print console devices and informations
3156 ide - IDE sub-system
3157 loop - infinite loop on address range
3158 loopw - infinite write loop on address range
3159 mtest - simple RAM test
3160 icache - enable or disable instruction cache
3161 dcache - enable or disable data cache
3162 reset - Perform RESET of the CPU
3163 echo - echo args to console
3164 version - print monitor version
3165 help - print online help
3166 ? - alias for 'help'
3169 Monitor Commands - Detailed Description:
3170 ========================================
3174 For now: just type "help <command>".
3177 Environment Variables:
3178 ======================
3180 U-Boot supports user configuration using Environment Variables which
3181 can be made persistent by saving to Flash memory.
3183 Environment Variables are set using "setenv", printed using
3184 "printenv", and saved to Flash using "saveenv". Using "setenv"
3185 without a value can be used to delete a variable from the
3186 environment. As long as you don't save the environment you are
3187 working with an in-memory copy. In case the Flash area containing the
3188 environment is erased by accident, a default environment is provided.
3190 Some configuration options can be set using Environment Variables.
3192 List of environment variables (most likely not complete):
3194 baudrate - see CONFIG_BAUDRATE
3196 bootdelay - see CONFIG_BOOTDELAY
3198 bootcmd - see CONFIG_BOOTCOMMAND
3200 bootargs - Boot arguments when booting an RTOS image
3202 bootfile - Name of the image to load with TFTP
3204 bootm_low - Memory range available for image processing in the bootm
3205 command can be restricted. This variable is given as
3206 a hexadecimal number and defines lowest address allowed
3207 for use by the bootm command. See also "bootm_size"
3208 environment variable. Address defined by "bootm_low" is
3209 also the base of the initial memory mapping for the Linux
3210 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3213 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3214 This variable is given as a hexadecimal number and it
3215 defines the size of the memory region starting at base
3216 address bootm_low that is accessible by the Linux kernel
3217 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3218 as the default value if it is defined, and bootm_size is
3221 bootm_size - Memory range available for image processing in the bootm
3222 command can be restricted. This variable is given as
3223 a hexadecimal number and defines the size of the region
3224 allowed for use by the bootm command. See also "bootm_low"
3225 environment variable.
3227 updatefile - Location of the software update file on a TFTP server, used
3228 by the automatic software update feature. Please refer to
3229 documentation in doc/README.update for more details.
3231 autoload - if set to "no" (any string beginning with 'n'),
3232 "bootp" will just load perform a lookup of the
3233 configuration from the BOOTP server, but not try to
3234 load any image using TFTP
3236 autostart - if set to "yes", an image loaded using the "bootp",
3237 "rarpboot", "tftpboot" or "diskboot" commands will
3238 be automatically started (by internally calling
3241 If set to "no", a standalone image passed to the
3242 "bootm" command will be copied to the load address
3243 (and eventually uncompressed), but NOT be started.
3244 This can be used to load and uncompress arbitrary
3247 i2cfast - (PPC405GP|PPC405EP only)
3248 if set to 'y' configures Linux I2C driver for fast
3249 mode (400kHZ). This environment variable is used in
3250 initialization code. So, for changes to be effective
3251 it must be saved and board must be reset.
3253 initrd_high - restrict positioning of initrd images:
3254 If this variable is not set, initrd images will be
3255 copied to the highest possible address in RAM; this
3256 is usually what you want since it allows for
3257 maximum initrd size. If for some reason you want to
3258 make sure that the initrd image is loaded below the
3259 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3260 variable to a value of "no" or "off" or "0".
3261 Alternatively, you can set it to a maximum upper
3262 address to use (U-Boot will still check that it
3263 does not overwrite the U-Boot stack and data).
3265 For instance, when you have a system with 16 MB
3266 RAM, and want to reserve 4 MB from use by Linux,
3267 you can do this by adding "mem=12M" to the value of
3268 the "bootargs" variable. However, now you must make
3269 sure that the initrd image is placed in the first
3270 12 MB as well - this can be done with
3272 setenv initrd_high 00c00000
3274 If you set initrd_high to 0xFFFFFFFF, this is an
3275 indication to U-Boot that all addresses are legal
3276 for the Linux kernel, including addresses in flash
3277 memory. In this case U-Boot will NOT COPY the
3278 ramdisk at all. This may be useful to reduce the
3279 boot time on your system, but requires that this
3280 feature is supported by your Linux kernel.
3282 ipaddr - IP address; needed for tftpboot command
3284 loadaddr - Default load address for commands like "bootp",
3285 "rarpboot", "tftpboot", "loadb" or "diskboot"
3287 loads_echo - see CONFIG_LOADS_ECHO
3289 serverip - TFTP server IP address; needed for tftpboot command
3291 bootretry - see CONFIG_BOOT_RETRY_TIME
3293 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3295 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3297 ethprime - When CONFIG_NET_MULTI is enabled controls which
3298 interface is used first.
3300 ethact - When CONFIG_NET_MULTI is enabled controls which
3301 interface is currently active. For example you
3302 can do the following
3304 => setenv ethact FEC
3305 => ping 192.168.0.1 # traffic sent on FEC
3306 => setenv ethact SCC
3307 => ping 10.0.0.1 # traffic sent on SCC
3309 ethrotate - When set to "no" U-Boot does not go through all
3310 available network interfaces.
3311 It just stays at the currently selected interface.
3313 netretry - When set to "no" each network operation will
3314 either succeed or fail without retrying.
3315 When set to "once" the network operation will
3316 fail when all the available network interfaces
3317 are tried once without success.
3318 Useful on scripts which control the retry operation
3321 npe_ucode - set load address for the NPE microcode
3323 tftpsrcport - If this is set, the value is used for TFTP's
3326 tftpdstport - If this is set, the value is used for TFTP's UDP
3327 destination port instead of the Well Know Port 69.
3329 tftpblocksize - Block size to use for TFTP transfers; if not set,
3330 we use the TFTP server's default block size
3332 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3333 seconds, minimum value is 1000 = 1 second). Defines
3334 when a packet is considered to be lost so it has to
3335 be retransmitted. The default is 5000 = 5 seconds.
3336 Lowering this value may make downloads succeed
3337 faster in networks with high packet loss rates or
3338 with unreliable TFTP servers.
3340 vlan - When set to a value < 4095 the traffic over
3341 Ethernet is encapsulated/received over 802.1q
3344 The following environment variables may be used and automatically
3345 updated by the network boot commands ("bootp" and "rarpboot"),
3346 depending the information provided by your boot server:
3348 bootfile - see above
3349 dnsip - IP address of your Domain Name Server
3350 dnsip2 - IP address of your secondary Domain Name Server
3351 gatewayip - IP address of the Gateway (Router) to use
3352 hostname - Target hostname
3354 netmask - Subnet Mask
3355 rootpath - Pathname of the root filesystem on the NFS server
3356 serverip - see above
3359 There are two special Environment Variables:
3361 serial# - contains hardware identification information such
3362 as type string and/or serial number
3363 ethaddr - Ethernet address
3365 These variables can be set only once (usually during manufacturing of
3366 the board). U-Boot refuses to delete or overwrite these variables
3367 once they have been set once.
3370 Further special Environment Variables:
3372 ver - Contains the U-Boot version string as printed
3373 with the "version" command. This variable is
3374 readonly (see CONFIG_VERSION_VARIABLE).
3377 Please note that changes to some configuration parameters may take
3378 only effect after the next boot (yes, that's just like Windoze :-).
3381 Command Line Parsing:
3382 =====================
3384 There are two different command line parsers available with U-Boot:
3385 the old "simple" one, and the much more powerful "hush" shell:
3387 Old, simple command line parser:
3388 --------------------------------
3390 - supports environment variables (through setenv / saveenv commands)
3391 - several commands on one line, separated by ';'
3392 - variable substitution using "... ${name} ..." syntax
3393 - special characters ('$', ';') can be escaped by prefixing with '\',
3395 setenv bootcmd bootm \${address}
3396 - You can also escape text by enclosing in single apostrophes, for example:
3397 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3402 - similar to Bourne shell, with control structures like
3403 if...then...else...fi, for...do...done; while...do...done,
3404 until...do...done, ...
3405 - supports environment ("global") variables (through setenv / saveenv
3406 commands) and local shell variables (through standard shell syntax
3407 "name=value"); only environment variables can be used with "run"
3413 (1) If a command line (or an environment variable executed by a "run"
3414 command) contains several commands separated by semicolon, and
3415 one of these commands fails, then the remaining commands will be
3418 (2) If you execute several variables with one call to run (i. e.
3419 calling run with a list of variables as arguments), any failing
3420 command will cause "run" to terminate, i. e. the remaining
3421 variables are not executed.
3423 Note for Redundant Ethernet Interfaces:
3424 =======================================
3426 Some boards come with redundant Ethernet interfaces; U-Boot supports
3427 such configurations and is capable of automatic selection of a
3428 "working" interface when needed. MAC assignment works as follows:
3430 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3431 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3432 "eth1addr" (=>eth1), "eth2addr", ...
3434 If the network interface stores some valid MAC address (for instance
3435 in SROM), this is used as default address if there is NO correspon-
3436 ding setting in the environment; if the corresponding environment
3437 variable is set, this overrides the settings in the card; that means:
3439 o If the SROM has a valid MAC address, and there is no address in the
3440 environment, the SROM's address is used.
3442 o If there is no valid address in the SROM, and a definition in the
3443 environment exists, then the value from the environment variable is
3446 o If both the SROM and the environment contain a MAC address, and
3447 both addresses are the same, this MAC address is used.
3449 o If both the SROM and the environment contain a MAC address, and the
3450 addresses differ, the value from the environment is used and a
3453 o If neither SROM nor the environment contain a MAC address, an error
3456 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3457 will be programmed into hardware as part of the initialization process. This
3458 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3459 The naming convention is as follows:
3460 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3465 U-Boot is capable of booting (and performing other auxiliary operations on)
3466 images in two formats:
3468 New uImage format (FIT)
3469 -----------------------
3471 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3472 to Flattened Device Tree). It allows the use of images with multiple
3473 components (several kernels, ramdisks, etc.), with contents protected by
3474 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3480 Old image format is based on binary files which can be basically anything,
3481 preceded by a special header; see the definitions in include/image.h for
3482 details; basically, the header defines the following image properties:
3484 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3485 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3486 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3487 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3489 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3490 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3491 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3492 * Compression Type (uncompressed, gzip, bzip2)
3498 The header is marked by a special Magic Number, and both the header
3499 and the data portions of the image are secured against corruption by
3506 Although U-Boot should support any OS or standalone application
3507 easily, the main focus has always been on Linux during the design of
3510 U-Boot includes many features that so far have been part of some
3511 special "boot loader" code within the Linux kernel. Also, any
3512 "initrd" images to be used are no longer part of one big Linux image;
3513 instead, kernel and "initrd" are separate images. This implementation
3514 serves several purposes:
3516 - the same features can be used for other OS or standalone
3517 applications (for instance: using compressed images to reduce the
3518 Flash memory footprint)
3520 - it becomes much easier to port new Linux kernel versions because
3521 lots of low-level, hardware dependent stuff are done by U-Boot
3523 - the same Linux kernel image can now be used with different "initrd"
3524 images; of course this also means that different kernel images can
3525 be run with the same "initrd". This makes testing easier (you don't
3526 have to build a new "zImage.initrd" Linux image when you just
3527 change a file in your "initrd"). Also, a field-upgrade of the
3528 software is easier now.
3534 Porting Linux to U-Boot based systems:
3535 ---------------------------------------
3537 U-Boot cannot save you from doing all the necessary modifications to
3538 configure the Linux device drivers for use with your target hardware
3539 (no, we don't intend to provide a full virtual machine interface to
3542 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3544 Just make sure your machine specific header file (for instance
3545 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3546 Information structure as we define in include/asm-<arch>/u-boot.h,
3547 and make sure that your definition of IMAP_ADDR uses the same value
3548 as your U-Boot configuration in CONFIG_SYS_IMMR.
3551 Configuring the Linux kernel:
3552 -----------------------------
3554 No specific requirements for U-Boot. Make sure you have some root
3555 device (initial ramdisk, NFS) for your target system.
3558 Building a Linux Image:
3559 -----------------------
3561 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3562 not used. If you use recent kernel source, a new build target
3563 "uImage" will exist which automatically builds an image usable by
3564 U-Boot. Most older kernels also have support for a "pImage" target,
3565 which was introduced for our predecessor project PPCBoot and uses a
3566 100% compatible format.
3575 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3576 encapsulate a compressed Linux kernel image with header information,
3577 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3579 * build a standard "vmlinux" kernel image (in ELF binary format):
3581 * convert the kernel into a raw binary image:
3583 ${CROSS_COMPILE}-objcopy -O binary \
3584 -R .note -R .comment \
3585 -S vmlinux linux.bin
3587 * compress the binary image:
3591 * package compressed binary image for U-Boot:
3593 mkimage -A ppc -O linux -T kernel -C gzip \
3594 -a 0 -e 0 -n "Linux Kernel Image" \
3595 -d linux.bin.gz uImage
3598 The "mkimage" tool can also be used to create ramdisk images for use
3599 with U-Boot, either separated from the Linux kernel image, or
3600 combined into one file. "mkimage" encapsulates the images with a 64
3601 byte header containing information about target architecture,
3602 operating system, image type, compression method, entry points, time
3603 stamp, CRC32 checksums, etc.
3605 "mkimage" can be called in two ways: to verify existing images and
3606 print the header information, or to build new images.
3608 In the first form (with "-l" option) mkimage lists the information
3609 contained in the header of an existing U-Boot image; this includes
3610 checksum verification:
3612 tools/mkimage -l image
3613 -l ==> list image header information
3615 The second form (with "-d" option) is used to build a U-Boot image
3616 from a "data file" which is used as image payload:
3618 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3619 -n name -d data_file image
3620 -A ==> set architecture to 'arch'
3621 -O ==> set operating system to 'os'
3622 -T ==> set image type to 'type'
3623 -C ==> set compression type 'comp'
3624 -a ==> set load address to 'addr' (hex)
3625 -e ==> set entry point to 'ep' (hex)
3626 -n ==> set image name to 'name'
3627 -d ==> use image data from 'datafile'
3629 Right now, all Linux kernels for PowerPC systems use the same load
3630 address (0x00000000), but the entry point address depends on the
3633 - 2.2.x kernels have the entry point at 0x0000000C,
3634 - 2.3.x and later kernels have the entry point at 0x00000000.
3636 So a typical call to build a U-Boot image would read:
3638 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3639 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3640 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3641 > examples/uImage.TQM850L
3642 Image Name: 2.4.4 kernel for TQM850L
3643 Created: Wed Jul 19 02:34:59 2000
3644 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3645 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3646 Load Address: 0x00000000
3647 Entry Point: 0x00000000
3649 To verify the contents of the image (or check for corruption):
3651 -> tools/mkimage -l examples/uImage.TQM850L
3652 Image Name: 2.4.4 kernel for TQM850L
3653 Created: Wed Jul 19 02:34:59 2000
3654 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3655 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3656 Load Address: 0x00000000
3657 Entry Point: 0x00000000
3659 NOTE: for embedded systems where boot time is critical you can trade
3660 speed for memory and install an UNCOMPRESSED image instead: this
3661 needs more space in Flash, but boots much faster since it does not
3662 need to be uncompressed:
3664 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3665 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3666 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3667 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3668 > examples/uImage.TQM850L-uncompressed
3669 Image Name: 2.4.4 kernel for TQM850L
3670 Created: Wed Jul 19 02:34:59 2000
3671 Image Type: PowerPC Linux Kernel Image (uncompressed)
3672 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3673 Load Address: 0x00000000
3674 Entry Point: 0x00000000
3677 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3678 when your kernel is intended to use an initial ramdisk:
3680 -> tools/mkimage -n 'Simple Ramdisk Image' \
3681 > -A ppc -O linux -T ramdisk -C gzip \
3682 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3683 Image Name: Simple Ramdisk Image
3684 Created: Wed Jan 12 14:01:50 2000
3685 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3686 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3687 Load Address: 0x00000000
3688 Entry Point: 0x00000000
3691 Installing a Linux Image:
3692 -------------------------
3694 To downloading a U-Boot image over the serial (console) interface,
3695 you must convert the image to S-Record format:
3697 objcopy -I binary -O srec examples/image examples/image.srec
3699 The 'objcopy' does not understand the information in the U-Boot
3700 image header, so the resulting S-Record file will be relative to
3701 address 0x00000000. To load it to a given address, you need to
3702 specify the target address as 'offset' parameter with the 'loads'
3705 Example: install the image to address 0x40100000 (which on the
3706 TQM8xxL is in the first Flash bank):
3708 => erase 40100000 401FFFFF
3714 ## Ready for S-Record download ...
3715 ~>examples/image.srec
3716 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3718 15989 15990 15991 15992
3719 [file transfer complete]
3721 ## Start Addr = 0x00000000
3724 You can check the success of the download using the 'iminfo' command;
3725 this includes a checksum verification so you can be sure no data
3726 corruption happened:
3730 ## Checking Image at 40100000 ...
3731 Image Name: 2.2.13 for initrd on TQM850L
3732 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3733 Data Size: 335725 Bytes = 327 kB = 0 MB
3734 Load Address: 00000000
3735 Entry Point: 0000000c
3736 Verifying Checksum ... OK
3742 The "bootm" command is used to boot an application that is stored in
3743 memory (RAM or Flash). In case of a Linux kernel image, the contents
3744 of the "bootargs" environment variable is passed to the kernel as
3745 parameters. You can check and modify this variable using the
3746 "printenv" and "setenv" commands:
3749 => printenv bootargs
3750 bootargs=root=/dev/ram
3752 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3754 => printenv bootargs
3755 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3758 ## Booting Linux kernel at 40020000 ...
3759 Image Name: 2.2.13 for NFS on TQM850L
3760 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3761 Data Size: 381681 Bytes = 372 kB = 0 MB
3762 Load Address: 00000000
3763 Entry Point: 0000000c
3764 Verifying Checksum ... OK
3765 Uncompressing Kernel Image ... OK
3766 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
3767 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3768 time_init: decrementer frequency = 187500000/60
3769 Calibrating delay loop... 49.77 BogoMIPS
3770 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3773 If you want to boot a Linux kernel with initial RAM disk, you pass
3774 the memory addresses of both the kernel and the initrd image (PPBCOOT
3775 format!) to the "bootm" command:
3777 => imi 40100000 40200000
3779 ## Checking Image at 40100000 ...
3780 Image Name: 2.2.13 for initrd on TQM850L
3781 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3782 Data Size: 335725 Bytes = 327 kB = 0 MB
3783 Load Address: 00000000
3784 Entry Point: 0000000c
3785 Verifying Checksum ... OK
3787 ## Checking Image at 40200000 ...
3788 Image Name: Simple Ramdisk Image
3789 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3790 Data Size: 566530 Bytes = 553 kB = 0 MB
3791 Load Address: 00000000
3792 Entry Point: 00000000
3793 Verifying Checksum ... OK
3795 => bootm 40100000 40200000
3796 ## Booting Linux kernel at 40100000 ...
3797 Image Name: 2.2.13 for initrd on TQM850L
3798 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3799 Data Size: 335725 Bytes = 327 kB = 0 MB
3800 Load Address: 00000000
3801 Entry Point: 0000000c
3802 Verifying Checksum ... OK
3803 Uncompressing Kernel Image ... OK
3804 ## Loading RAMDisk Image at 40200000 ...
3805 Image Name: Simple Ramdisk Image
3806 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3807 Data Size: 566530 Bytes = 553 kB = 0 MB
3808 Load Address: 00000000
3809 Entry Point: 00000000
3810 Verifying Checksum ... OK
3811 Loading Ramdisk ... OK
3812 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
3813 Boot arguments: root=/dev/ram
3814 time_init: decrementer frequency = 187500000/60
3815 Calibrating delay loop... 49.77 BogoMIPS
3817 RAMDISK: Compressed image found at block 0
3818 VFS: Mounted root (ext2 filesystem).
3822 Boot Linux and pass a flat device tree:
3825 First, U-Boot must be compiled with the appropriate defines. See the section
3826 titled "Linux Kernel Interface" above for a more in depth explanation. The
3827 following is an example of how to start a kernel and pass an updated
3833 oft=oftrees/mpc8540ads.dtb
3834 => tftp $oftaddr $oft
3835 Speed: 1000, full duplex
3837 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3838 Filename 'oftrees/mpc8540ads.dtb'.
3839 Load address: 0x300000
3842 Bytes transferred = 4106 (100a hex)
3843 => tftp $loadaddr $bootfile
3844 Speed: 1000, full duplex
3846 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3848 Load address: 0x200000
3849 Loading:############
3851 Bytes transferred = 1029407 (fb51f hex)
3856 => bootm $loadaddr - $oftaddr
3857 ## Booting image at 00200000 ...
3858 Image Name: Linux-2.6.17-dirty
3859 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3860 Data Size: 1029343 Bytes = 1005.2 kB
3861 Load Address: 00000000
3862 Entry Point: 00000000
3863 Verifying Checksum ... OK
3864 Uncompressing Kernel Image ... OK
3865 Booting using flat device tree at 0x300000
3866 Using MPC85xx ADS machine description
3867 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3871 More About U-Boot Image Types:
3872 ------------------------------
3874 U-Boot supports the following image types:
3876 "Standalone Programs" are directly runnable in the environment
3877 provided by U-Boot; it is expected that (if they behave
3878 well) you can continue to work in U-Boot after return from
3879 the Standalone Program.
3880 "OS Kernel Images" are usually images of some Embedded OS which
3881 will take over control completely. Usually these programs
3882 will install their own set of exception handlers, device
3883 drivers, set up the MMU, etc. - this means, that you cannot
3884 expect to re-enter U-Boot except by resetting the CPU.
3885 "RAMDisk Images" are more or less just data blocks, and their
3886 parameters (address, size) are passed to an OS kernel that is
3888 "Multi-File Images" contain several images, typically an OS
3889 (Linux) kernel image and one or more data images like
3890 RAMDisks. This construct is useful for instance when you want
3891 to boot over the network using BOOTP etc., where the boot
3892 server provides just a single image file, but you want to get
3893 for instance an OS kernel and a RAMDisk image.
3895 "Multi-File Images" start with a list of image sizes, each
3896 image size (in bytes) specified by an "uint32_t" in network
3897 byte order. This list is terminated by an "(uint32_t)0".
3898 Immediately after the terminating 0 follow the images, one by
3899 one, all aligned on "uint32_t" boundaries (size rounded up to
3900 a multiple of 4 bytes).
3902 "Firmware Images" are binary images containing firmware (like
3903 U-Boot or FPGA images) which usually will be programmed to
3906 "Script files" are command sequences that will be executed by
3907 U-Boot's command interpreter; this feature is especially
3908 useful when you configure U-Boot to use a real shell (hush)
3909 as command interpreter.
3915 One of the features of U-Boot is that you can dynamically load and
3916 run "standalone" applications, which can use some resources of
3917 U-Boot like console I/O functions or interrupt services.
3919 Two simple examples are included with the sources:
3924 'examples/hello_world.c' contains a small "Hello World" Demo
3925 application; it is automatically compiled when you build U-Boot.
3926 It's configured to run at address 0x00040004, so you can play with it
3930 ## Ready for S-Record download ...
3931 ~>examples/hello_world.srec
3932 1 2 3 4 5 6 7 8 9 10 11 ...
3933 [file transfer complete]
3935 ## Start Addr = 0x00040004
3937 => go 40004 Hello World! This is a test.
3938 ## Starting application at 0x00040004 ...
3949 Hit any key to exit ...
3951 ## Application terminated, rc = 0x0
3953 Another example, which demonstrates how to register a CPM interrupt
3954 handler with the U-Boot code, can be found in 'examples/timer.c'.
3955 Here, a CPM timer is set up to generate an interrupt every second.
3956 The interrupt service routine is trivial, just printing a '.'
3957 character, but this is just a demo program. The application can be
3958 controlled by the following keys:
3960 ? - print current values og the CPM Timer registers
3961 b - enable interrupts and start timer
3962 e - stop timer and disable interrupts
3963 q - quit application
3966 ## Ready for S-Record download ...
3967 ~>examples/timer.srec
3968 1 2 3 4 5 6 7 8 9 10 11 ...
3969 [file transfer complete]
3971 ## Start Addr = 0x00040004
3974 ## Starting application at 0x00040004 ...
3977 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3980 [q, b, e, ?] Set interval 1000000 us
3983 [q, b, e, ?] ........
3984 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3987 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3990 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3993 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3995 [q, b, e, ?] ...Stopping timer
3997 [q, b, e, ?] ## Application terminated, rc = 0x0
4003 Over time, many people have reported problems when trying to use the
4004 "minicom" terminal emulation program for serial download. I (wd)
4005 consider minicom to be broken, and recommend not to use it. Under
4006 Unix, I recommend to use C-Kermit for general purpose use (and
4007 especially for kermit binary protocol download ("loadb" command), and
4008 use "cu" for S-Record download ("loads" command).
4010 Nevertheless, if you absolutely want to use it try adding this
4011 configuration to your "File transfer protocols" section:
4013 Name Program Name U/D FullScr IO-Red. Multi
4014 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4015 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4021 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4022 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4024 Building requires a cross environment; it is known to work on
4025 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4026 need gmake since the Makefiles are not compatible with BSD make).
4027 Note that the cross-powerpc package does not install include files;
4028 attempting to build U-Boot will fail because <machine/ansi.h> is
4029 missing. This file has to be installed and patched manually:
4031 # cd /usr/pkg/cross/powerpc-netbsd/include
4033 # ln -s powerpc machine
4034 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4035 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4037 Native builds *don't* work due to incompatibilities between native
4038 and U-Boot include files.
4040 Booting assumes that (the first part of) the image booted is a
4041 stage-2 loader which in turn loads and then invokes the kernel
4042 proper. Loader sources will eventually appear in the NetBSD source
4043 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4044 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4047 Implementation Internals:
4048 =========================
4050 The following is not intended to be a complete description of every
4051 implementation detail. However, it should help to understand the
4052 inner workings of U-Boot and make it easier to port it to custom
4056 Initial Stack, Global Data:
4057 ---------------------------
4059 The implementation of U-Boot is complicated by the fact that U-Boot
4060 starts running out of ROM (flash memory), usually without access to
4061 system RAM (because the memory controller is not initialized yet).
4062 This means that we don't have writable Data or BSS segments, and BSS
4063 is not initialized as zero. To be able to get a C environment working
4064 at all, we have to allocate at least a minimal stack. Implementation
4065 options for this are defined and restricted by the CPU used: Some CPU
4066 models provide on-chip memory (like the IMMR area on MPC8xx and
4067 MPC826x processors), on others (parts of) the data cache can be
4068 locked as (mis-) used as memory, etc.
4070 Chris Hallinan posted a good summary of these issues to the
4071 U-Boot mailing list:
4073 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4074 From: "Chris Hallinan" <clh@net1plus.com>
4075 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4078 Correct me if I'm wrong, folks, but the way I understand it
4079 is this: Using DCACHE as initial RAM for Stack, etc, does not
4080 require any physical RAM backing up the cache. The cleverness
4081 is that the cache is being used as a temporary supply of
4082 necessary storage before the SDRAM controller is setup. It's
4083 beyond the scope of this list to explain the details, but you
4084 can see how this works by studying the cache architecture and
4085 operation in the architecture and processor-specific manuals.
4087 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4088 is another option for the system designer to use as an
4089 initial stack/RAM area prior to SDRAM being available. Either
4090 option should work for you. Using CS 4 should be fine if your
4091 board designers haven't used it for something that would
4092 cause you grief during the initial boot! It is frequently not
4095 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4096 with your processor/board/system design. The default value
4097 you will find in any recent u-boot distribution in
4098 walnut.h should work for you. I'd set it to a value larger
4099 than your SDRAM module. If you have a 64MB SDRAM module, set
4100 it above 400_0000. Just make sure your board has no resources
4101 that are supposed to respond to that address! That code in
4102 start.S has been around a while and should work as is when
4103 you get the config right.
4108 It is essential to remember this, since it has some impact on the C
4109 code for the initialization procedures:
4111 * Initialized global data (data segment) is read-only. Do not attempt
4114 * Do not use any uninitialized global data (or implicitely initialized
4115 as zero data - BSS segment) at all - this is undefined, initiali-
4116 zation is performed later (when relocating to RAM).
4118 * Stack space is very limited. Avoid big data buffers or things like
4121 Having only the stack as writable memory limits means we cannot use
4122 normal global data to share information beween the code. But it
4123 turned out that the implementation of U-Boot can be greatly
4124 simplified by making a global data structure (gd_t) available to all
4125 functions. We could pass a pointer to this data as argument to _all_
4126 functions, but this would bloat the code. Instead we use a feature of
4127 the GCC compiler (Global Register Variables) to share the data: we
4128 place a pointer (gd) to the global data into a register which we
4129 reserve for this purpose.
4131 When choosing a register for such a purpose we are restricted by the
4132 relevant (E)ABI specifications for the current architecture, and by
4133 GCC's implementation.
4135 For PowerPC, the following registers have specific use:
4137 R2: reserved for system use
4138 R3-R4: parameter passing and return values
4139 R5-R10: parameter passing
4140 R13: small data area pointer
4144 (U-Boot also uses R12 as internal GOT pointer. r12
4145 is a volatile register so r12 needs to be reset when
4146 going back and forth between asm and C)
4148 ==> U-Boot will use R2 to hold a pointer to the global data
4150 Note: on PPC, we could use a static initializer (since the
4151 address of the global data structure is known at compile time),
4152 but it turned out that reserving a register results in somewhat
4153 smaller code - although the code savings are not that big (on
4154 average for all boards 752 bytes for the whole U-Boot image,
4155 624 text + 127 data).
4157 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4158 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4160 ==> U-Boot will use P3 to hold a pointer to the global data
4162 On ARM, the following registers are used:
4164 R0: function argument word/integer result
4165 R1-R3: function argument word
4167 R10: stack limit (used only if stack checking if enabled)
4168 R11: argument (frame) pointer
4169 R12: temporary workspace
4172 R15: program counter
4174 ==> U-Boot will use R8 to hold a pointer to the global data
4176 On Nios II, the ABI is documented here:
4177 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4179 ==> U-Boot will use gp to hold a pointer to the global data
4181 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4182 to access small data sections, so gp is free.
4184 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4185 or current versions of GCC may "optimize" the code too much.
4190 U-Boot runs in system state and uses physical addresses, i.e. the
4191 MMU is not used either for address mapping nor for memory protection.
4193 The available memory is mapped to fixed addresses using the memory
4194 controller. In this process, a contiguous block is formed for each
4195 memory type (Flash, SDRAM, SRAM), even when it consists of several
4196 physical memory banks.
4198 U-Boot is installed in the first 128 kB of the first Flash bank (on
4199 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4200 booting and sizing and initializing DRAM, the code relocates itself
4201 to the upper end of DRAM. Immediately below the U-Boot code some
4202 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4203 configuration setting]. Below that, a structure with global Board
4204 Info data is placed, followed by the stack (growing downward).
4206 Additionally, some exception handler code is copied to the low 8 kB
4207 of DRAM (0x00000000 ... 0x00001FFF).
4209 So a typical memory configuration with 16 MB of DRAM could look like
4212 0x0000 0000 Exception Vector code
4215 0x0000 2000 Free for Application Use
4221 0x00FB FF20 Monitor Stack (Growing downward)
4222 0x00FB FFAC Board Info Data and permanent copy of global data
4223 0x00FC 0000 Malloc Arena
4226 0x00FE 0000 RAM Copy of Monitor Code
4227 ... eventually: LCD or video framebuffer
4228 ... eventually: pRAM (Protected RAM - unchanged by reset)
4229 0x00FF FFFF [End of RAM]
4232 System Initialization:
4233 ----------------------
4235 In the reset configuration, U-Boot starts at the reset entry point
4236 (on most PowerPC systems at address 0x00000100). Because of the reset
4237 configuration for CS0# this is a mirror of the onboard Flash memory.
4238 To be able to re-map memory U-Boot then jumps to its link address.
4239 To be able to implement the initialization code in C, a (small!)
4240 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4241 which provide such a feature like MPC8xx or MPC8260), or in a locked
4242 part of the data cache. After that, U-Boot initializes the CPU core,
4243 the caches and the SIU.
4245 Next, all (potentially) available memory banks are mapped using a
4246 preliminary mapping. For example, we put them on 512 MB boundaries
4247 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4248 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4249 programmed for SDRAM access. Using the temporary configuration, a
4250 simple memory test is run that determines the size of the SDRAM
4253 When there is more than one SDRAM bank, and the banks are of
4254 different size, the largest is mapped first. For equal size, the first
4255 bank (CS2#) is mapped first. The first mapping is always for address
4256 0x00000000, with any additional banks following immediately to create
4257 contiguous memory starting from 0.
4259 Then, the monitor installs itself at the upper end of the SDRAM area
4260 and allocates memory for use by malloc() and for the global Board
4261 Info data; also, the exception vector code is copied to the low RAM
4262 pages, and the final stack is set up.
4264 Only after this relocation will you have a "normal" C environment;
4265 until that you are restricted in several ways, mostly because you are
4266 running from ROM, and because the code will have to be relocated to a
4270 U-Boot Porting Guide:
4271 ----------------------
4273 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4277 int main(int argc, char *argv[])
4279 sighandler_t no_more_time;
4281 signal(SIGALRM, no_more_time);
4282 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4284 if (available_money > available_manpower) {
4285 Pay consultant to port U-Boot;
4289 Download latest U-Boot source;
4291 Subscribe to u-boot mailing list;
4294 email("Hi, I am new to U-Boot, how do I get started?");
4297 Read the README file in the top level directory;
4298 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4299 Read applicable doc/*.README;
4300 Read the source, Luke;
4301 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4304 if (available_money > toLocalCurrency ($2500))
4307 Add a lot of aggravation and time;
4309 if (a similar board exists) { /* hopefully... */
4310 cp -a board/<similar> board/<myboard>
4311 cp include/configs/<similar>.h include/configs/<myboard>.h
4313 Create your own board support subdirectory;
4314 Create your own board include/configs/<myboard>.h file;
4316 Edit new board/<myboard> files
4317 Edit new include/configs/<myboard>.h
4322 Add / modify source code;
4326 email("Hi, I am having problems...");
4328 Send patch file to the U-Boot email list;
4329 if (reasonable critiques)
4330 Incorporate improvements from email list code review;
4332 Defend code as written;
4338 void no_more_time (int sig)
4347 All contributions to U-Boot should conform to the Linux kernel
4348 coding style; see the file "Documentation/CodingStyle" and the script
4349 "scripts/Lindent" in your Linux kernel source directory. In sources
4350 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4351 spaces before parameters to function calls) is actually used.
4353 Source files originating from a different project (for example the
4354 MTD subsystem) are generally exempt from these guidelines and are not
4355 reformated to ease subsequent migration to newer versions of those
4358 Please note that U-Boot is implemented in C (and to some small parts in
4359 Assembler); no C++ is used, so please do not use C++ style comments (//)
4362 Please also stick to the following formatting rules:
4363 - remove any trailing white space
4364 - use TAB characters for indentation, not spaces
4365 - make sure NOT to use DOS '\r\n' line feeds
4366 - do not add more than 2 empty lines to source files
4367 - do not add trailing empty lines to source files
4369 Submissions which do not conform to the standards may be returned
4370 with a request to reformat the changes.
4376 Since the number of patches for U-Boot is growing, we need to
4377 establish some rules. Submissions which do not conform to these rules
4378 may be rejected, even when they contain important and valuable stuff.
4380 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4382 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4383 see http://lists.denx.de/mailman/listinfo/u-boot
4385 When you send a patch, please include the following information with
4388 * For bug fixes: a description of the bug and how your patch fixes
4389 this bug. Please try to include a way of demonstrating that the
4390 patch actually fixes something.
4392 * For new features: a description of the feature and your
4395 * A CHANGELOG entry as plaintext (separate from the patch)
4397 * For major contributions, your entry to the CREDITS file
4399 * When you add support for a new board, don't forget to add this
4400 board to the MAKEALL script, too.
4402 * If your patch adds new configuration options, don't forget to
4403 document these in the README file.
4405 * The patch itself. If you are using git (which is *strongly*
4406 recommended) you can easily generate the patch using the
4407 "git-format-patch". If you then use "git-send-email" to send it to
4408 the U-Boot mailing list, you will avoid most of the common problems
4409 with some other mail clients.
4411 If you cannot use git, use "diff -purN OLD NEW". If your version of
4412 diff does not support these options, then get the latest version of
4415 The current directory when running this command shall be the parent
4416 directory of the U-Boot source tree (i. e. please make sure that
4417 your patch includes sufficient directory information for the
4420 We prefer patches as plain text. MIME attachments are discouraged,
4421 and compressed attachments must not be used.
4423 * If one logical set of modifications affects or creates several
4424 files, all these changes shall be submitted in a SINGLE patch file.
4426 * Changesets that contain different, unrelated modifications shall be
4427 submitted as SEPARATE patches, one patch per changeset.
4432 * Before sending the patch, run the MAKEALL script on your patched
4433 source tree and make sure that no errors or warnings are reported
4434 for any of the boards.
4436 * Keep your modifications to the necessary minimum: A patch
4437 containing several unrelated changes or arbitrary reformats will be
4438 returned with a request to re-formatting / split it.
4440 * If you modify existing code, make sure that your new code does not
4441 add to the memory footprint of the code ;-) Small is beautiful!
4442 When adding new features, these should compile conditionally only
4443 (using #ifdef), and the resulting code with the new feature
4444 disabled must not need more memory than the old code without your
4447 * Remember that there is a size limit of 100 kB per message on the
4448 u-boot mailing list. Bigger patches will be moderated. If they are
4449 reasonable and not too big, they will be acknowledged. But patches
4450 bigger than the size limit should be avoided.