2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - i386 Files specific to i386 CPUs
136 - ixp Files specific to Intel XScale IXP CPUs
137 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
138 - mips Files specific to MIPS CPUs
139 - mpc5xx Files specific to Freescale MPC5xx CPUs
140 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
141 - mpc8xx Files specific to Freescale MPC8xx CPUs
142 - mpc8220 Files specific to Freescale MPC8220 CPUs
143 - mpc824x Files specific to Freescale MPC824x CPUs
144 - mpc8260 Files specific to Freescale MPC8260 CPUs
145 - mpc85xx Files specific to Freescale MPC85xx CPUs
146 - nios Files specific to Altera NIOS CPUs
147 - nios2 Files specific to Altera Nios-II CPUs
148 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
149 - pxa Files specific to Intel XScale PXA CPUs
150 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
151 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
152 - disk Code for disk drive partition handling
153 - doc Documentation (don't expect too much)
154 - drivers Commonly used device drivers
155 - dtt Digital Thermometer and Thermostat drivers
156 - examples Example code for standalone applications, etc.
157 - include Header Files
158 - lib_arm Files generic to ARM architecture
159 - lib_generic Files generic to all architectures
160 - lib_i386 Files generic to i386 architecture
161 - lib_m68k Files generic to m68k architecture
162 - lib_mips Files generic to MIPS architecture
163 - lib_nios Files generic to NIOS architecture
164 - lib_ppc Files generic to PowerPC architecture
165 - net Networking code
166 - post Power On Self Test
167 - rtc Real Time Clock drivers
168 - tools Tools to build S-Record or U-Boot images, etc.
170 Software Configuration:
171 =======================
173 Configuration is usually done using C preprocessor defines; the
174 rationale behind that is to avoid dead code whenever possible.
176 There are two classes of configuration variables:
178 * Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
182 * Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
187 Later we will add a configuration tool - probably similar to or even
188 identical to what's used for the Linux kernel. Right now, we have to
189 do the configuration by hand, which means creating some symbolic
190 links and editing some configuration files. We use the TQM8xxL boards
194 Selection of Processor Architecture and Board Type:
195 ---------------------------------------------------
197 For all supported boards there are ready-to-use default
198 configurations available; just type "make <board_name>_config".
200 Example: For a TQM823L module type:
205 For the Cogent platform, you need to specify the cpu type as well;
206 e.g. "make cogent_mpc8xx_config". And also configure the cogent
207 directory according to the instructions in cogent/README.
210 Configuration Options:
211 ----------------------
213 Configuration depends on the combination of board and CPU type; all
214 such information is kept in a configuration file
215 "include/configs/<board_name>.h".
217 Example: For a TQM823L module, all configuration settings are in
218 "include/configs/TQM823L.h".
221 Many of the options are named exactly as the corresponding Linux
222 kernel configuration options. The intention is to make it easier to
223 build a config tool - later.
226 The following options need to be configured:
228 - CPU Type: Define exactly one of
232 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
235 or CONFIG_MPC824X, CONFIG_MPC8260
250 MicroBlaze based CPUs:
251 ----------------------
255 ----------------------
259 - Board Type: Define exactly one of
261 PowerPC based boards:
262 ---------------------
264 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCIPPC2
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC6
266 CONFIG_AMX860 CONFIG_GTH CONFIG_pcu_e
267 CONFIG_AP1000 CONFIG_gw8260 CONFIG_PIP405
268 CONFIG_AR405 CONFIG_hermes CONFIG_PM826
269 CONFIG_BAB7xx CONFIG_hymod CONFIG_ppmc8260
270 CONFIG_c2mon CONFIG_IAD210 CONFIG_QS823
271 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS850
272 CONFIG_CCM CONFIG_IP860 CONFIG_QS860T
273 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_RBC823
274 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RPXClassic
275 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXlite
276 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXsuper
277 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_rsdproto
278 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_sacsng
279 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_Sandpoint8240
280 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8245
281 CONFIG_CSB272 CONFIG_LANTEC CONFIG_sbc8260
282 CONFIG_CU824 CONFIG_lwmon CONFIG_sbc8560
283 CONFIG_DASA_SIM CONFIG_MBX CONFIG_SM850
284 CONFIG_DB64360 CONFIG_MBX860T CONFIG_SPD823TS
285 CONFIG_DB64460 CONFIG_MHPC CONFIG_STXGP3
286 CONFIG_DU405 CONFIG_MIP405 CONFIG_SXNI855T
287 CONFIG_DUET_ADS CONFIG_MOUSSE CONFIG_TQM823L
288 CONFIG_EBONY CONFIG_MPC8260ADS CONFIG_TQM8260
289 CONFIG_ELPPC CONFIG_MPC8540ADS CONFIG_TQM850L
290 CONFIG_ELPT860 CONFIG_MPC8540EVAL CONFIG_TQM855L
291 CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM860L
292 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TTTech
293 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_UTX8245
294 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_V37
295 CONFIG_EVB64260 CONFIG_NETTA CONFIG_W7OLMC
296 CONFIG_FADS823 CONFIG_NETVIA CONFIG_W7OLMG
297 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_WALNUT
298 CONFIG_FADS860T CONFIG_OCRTC CONFIG_ZPC1900
299 CONFIG_FLAGADM CONFIG_ORSG CONFIG_ZUMA
300 CONFIG_FPS850L CONFIG_OXC
301 CONFIG_FPS860L CONFIG_PCI405
306 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
307 CONFIG_CSB637, CONFIG_DNP1110, CONFIG_EP7312,
308 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
309 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_KB9202,
310 CONFIG_LART, CONFIG_LPD7A400, CONFIG_LUBBOCK,
311 CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
312 CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
313 CONFIG_TRAB, CONFIG_VCMA9
315 MicroBlaze based boards:
316 ------------------------
321 ------------------------
323 CONFIG_PCI5441 CONFIG_PK1C20
326 - CPU Module Type: (if CONFIG_COGENT is defined)
327 Define exactly one of
329 --- FIXME --- not tested yet:
330 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
331 CONFIG_CMA287_23, CONFIG_CMA287_50
333 - Motherboard Type: (if CONFIG_COGENT is defined)
334 Define exactly one of
335 CONFIG_CMA101, CONFIG_CMA102
337 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
338 Define one or more of
341 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
342 Define one or more of
343 CONFIG_LCD_HEARTBEAT - update a character position on
344 the lcd display every second with
347 - Board flavour: (if CONFIG_MPC8260ADS is defined)
350 CFG_8260ADS - original MPC8260ADS
351 CFG_8266ADS - MPC8266ADS
352 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
353 CFG_8272ADS - MPC8272ADS
355 - MPC824X Family Member (if CONFIG_MPC824X is defined)
356 Define exactly one of
357 CONFIG_MPC8240, CONFIG_MPC8245
359 - 8xx CPU Options: (if using an MPC8xx cpu)
360 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
361 get_gclk_freq() cannot work
362 e.g. if there is no 32KHz
363 reference PIT/RTC clock
364 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
367 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
370 CONFIG_8xx_CPUCLK_DEFAULT
371 See doc/README.MPC866
375 Define this to measure the actual CPU clock instead
376 of relying on the correctness of the configured
377 values. Mostly useful for board bringup to make sure
378 the PLL is locked at the intended frequency. Note
379 that this requires a (stable) reference clock (32 kHz
380 RTC clock or CFG_8XX_XIN)
382 - Linux Kernel Interface:
385 U-Boot stores all clock information in Hz
386 internally. For binary compatibility with older Linux
387 kernels (which expect the clocks passed in the
388 bd_info data to be in MHz) the environment variable
389 "clocks_in_mhz" can be defined so that U-Boot
390 converts clock data to MHZ before passing it to the
392 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
393 "clocks_in_mhz=1" is automatically included in the
396 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
398 When transfering memsize parameter to linux, some versions
399 expect it to be in bytes, others in MB.
400 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
404 New kernel versions are expecting firmware settings to be
405 passed using flat open firmware trees.
406 The environment variable "disable_of", when set, disables this
409 CONFIG_OF_FLAT_TREE_MAX_SIZE
411 The maximum size of the constructed OF tree.
413 OF_CPU - The proper name of the cpus node.
414 OF_SOC - The proper name of the soc node.
415 OF_TBCLK - The timebase frequency.
416 OF_STDOUT_PATH - The path to the console device
420 The resulting flat device tree will have a copy of the bd_t.
421 Space should be pre-allocated in the dts for the bd_t.
423 CONFIG_OF_HAS_UBOOT_ENV
425 The resulting flat device tree will have a copy of u-boot's
426 environment variables
428 CONFIG_OF_BOARD_SETUP
430 Board code has addition modification that it wants to make
431 to the flat device tree before handing it off to the kernel
436 Define this if you want support for Amba PrimeCell PL010 UARTs.
440 Define this if you want support for Amba PrimeCell PL011 UARTs.
444 If you have Amba PrimeCell PL011 UARTs, set this variable to
445 the clock speed of the UARTs.
449 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
450 define this to a list of base addresses for each (supported)
451 port. See e.g. include/configs/versatile.h
455 Depending on board, define exactly one serial port
456 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
457 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
458 console by defining CONFIG_8xx_CONS_NONE
460 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
461 port routines must be defined elsewhere
462 (i.e. serial_init(), serial_getc(), ...)
465 Enables console device for a color framebuffer. Needs following
466 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
467 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
469 VIDEO_HW_RECTFILL graphic chip supports
472 VIDEO_HW_BITBLT graphic chip supports
473 bit-blit (cf. smiLynxEM)
474 VIDEO_VISIBLE_COLS visible pixel columns
476 VIDEO_VISIBLE_ROWS visible pixel rows
477 VIDEO_PIXEL_SIZE bytes per pixel
478 VIDEO_DATA_FORMAT graphic data format
479 (0-5, cf. cfb_console.c)
480 VIDEO_FB_ADRS framebuffer address
481 VIDEO_KBD_INIT_FCT keyboard int fct
482 (i.e. i8042_kbd_init())
483 VIDEO_TSTC_FCT test char fct
485 VIDEO_GETC_FCT get char fct
487 CONFIG_CONSOLE_CURSOR cursor drawing on/off
488 (requires blink timer
490 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
491 CONFIG_CONSOLE_TIME display time/date info in
493 (requires CFG_CMD_DATE)
494 CONFIG_VIDEO_LOGO display Linux logo in
496 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
497 linux_logo.h for logo.
498 Requires CONFIG_VIDEO_LOGO
499 CONFIG_CONSOLE_EXTRA_INFO
500 addional board info beside
503 When CONFIG_CFB_CONSOLE is defined, video console is
504 default i/o. Serial console can be forced with
505 environment 'console=serial'.
507 When CONFIG_SILENT_CONSOLE is defined, all console
508 messages (by U-Boot and Linux!) can be silenced with
509 the "silent" environment variable. See
510 doc/README.silent for more information.
513 CONFIG_BAUDRATE - in bps
514 Select one of the baudrates listed in
515 CFG_BAUDRATE_TABLE, see below.
516 CFG_BRGCLK_PRESCALE, baudrate prescale
518 - Interrupt driven serial port input:
519 CONFIG_SERIAL_SOFTWARE_FIFO
522 Use an interrupt handler for receiving data on the
523 serial port. It also enables using hardware handshake
524 (RTS/CTS) and UART's built-in FIFO. Set the number of
525 bytes the interrupt driven input buffer should have.
527 Leave undefined to disable this feature, including
528 disable the buffer and hardware handshake.
530 - Console UART Number:
534 If defined internal UART1 (and not UART0) is used
535 as default U-Boot console.
537 - Boot Delay: CONFIG_BOOTDELAY - in seconds
538 Delay before automatically booting the default image;
539 set to -1 to disable autoboot.
541 See doc/README.autoboot for these options that
542 work with CONFIG_BOOTDELAY. None are required.
543 CONFIG_BOOT_RETRY_TIME
544 CONFIG_BOOT_RETRY_MIN
545 CONFIG_AUTOBOOT_KEYED
546 CONFIG_AUTOBOOT_PROMPT
547 CONFIG_AUTOBOOT_DELAY_STR
548 CONFIG_AUTOBOOT_STOP_STR
549 CONFIG_AUTOBOOT_DELAY_STR2
550 CONFIG_AUTOBOOT_STOP_STR2
551 CONFIG_ZERO_BOOTDELAY_CHECK
552 CONFIG_RESET_TO_RETRY
556 Only needed when CONFIG_BOOTDELAY is enabled;
557 define a command string that is automatically executed
558 when no character is read on the console interface
559 within "Boot Delay" after reset.
562 This can be used to pass arguments to the bootm
563 command. The value of CONFIG_BOOTARGS goes into the
564 environment value "bootargs".
566 CONFIG_RAMBOOT and CONFIG_NFSBOOT
567 The value of these goes into the environment as
568 "ramboot" and "nfsboot" respectively, and can be used
569 as a convenience, when switching between booting from
575 When this option is #defined, the existence of the
576 environment variable "preboot" will be checked
577 immediately before starting the CONFIG_BOOTDELAY
578 countdown and/or running the auto-boot command resp.
579 entering interactive mode.
581 This feature is especially useful when "preboot" is
582 automatically generated or modified. For an example
583 see the LWMON board specific code: here "preboot" is
584 modified when the user holds down a certain
585 combination of keys on the (special) keyboard when
588 - Serial Download Echo Mode:
590 If defined to 1, all characters received during a
591 serial download (using the "loads" command) are
592 echoed back. This might be needed by some terminal
593 emulations (like "cu"), but may as well just take
594 time on others. This setting #define's the initial
595 value of the "loads_echo" environment variable.
597 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
599 Select one of the baudrates listed in
600 CFG_BAUDRATE_TABLE, see below.
604 Most monitor functions can be selected (or
605 de-selected) by adjusting the definition of
606 CONFIG_COMMANDS; to select individual functions,
607 #define CONFIG_COMMANDS by "OR"ing any of the
610 #define enables commands:
611 -------------------------
612 CFG_CMD_ASKENV * ask for env variable
613 CFG_CMD_AUTOSCRIPT Autoscript Support
615 CFG_CMD_BEDBUG * Include BedBug Debugger
616 CFG_CMD_BMP * BMP support
617 CFG_CMD_BSP * Board specific commands
619 CFG_CMD_CACHE * icache, dcache
620 CFG_CMD_CONSOLE coninfo
621 CFG_CMD_DATE * support for RTC, date/time...
622 CFG_CMD_DHCP * DHCP support
623 CFG_CMD_DIAG * Diagnostics
624 CFG_CMD_DOC * Disk-On-Chip Support
625 CFG_CMD_DTT * Digital Therm and Thermostat
626 CFG_CMD_ECHO * echo arguments
627 CFG_CMD_EEPROM * EEPROM read/write support
628 CFG_CMD_ELF * bootelf, bootvx
630 CFG_CMD_FDC * Floppy Disk Support
631 CFG_CMD_FAT * FAT partition support
632 CFG_CMD_FDOS * Dos diskette Support
633 CFG_CMD_FLASH flinfo, erase, protect
634 CFG_CMD_FPGA FPGA device initialization support
635 CFG_CMD_HWFLOW * RTS/CTS hw flow control
636 CFG_CMD_I2C * I2C serial bus support
637 CFG_CMD_IDE * IDE harddisk support
639 CFG_CMD_IMLS List all found images
640 CFG_CMD_IMMAP * IMMR dump support
641 CFG_CMD_IRQ * irqinfo
642 CFG_CMD_ITEST Integer/string test of 2 values
643 CFG_CMD_JFFS2 * JFFS2 Support
647 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
649 CFG_CMD_MISC Misc functions like sleep etc
650 CFG_CMD_MMC * MMC memory mapped support
651 CFG_CMD_MII * MII utility commands
652 CFG_CMD_NAND * NAND support
653 CFG_CMD_NET bootp, tftpboot, rarpboot
654 CFG_CMD_PCI * pciinfo
655 CFG_CMD_PCMCIA * PCMCIA support
656 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
657 CFG_CMD_PORTIO * Port I/O
658 CFG_CMD_REGINFO * Register dump
659 CFG_CMD_RUN run command in env variable
660 CFG_CMD_SAVES * save S record dump
661 CFG_CMD_SCSI * SCSI Support
662 CFG_CMD_SDRAM * print SDRAM configuration information
663 (requires CFG_CMD_I2C)
664 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
665 CFG_CMD_SPI * SPI serial bus support
666 CFG_CMD_USB * USB support
667 CFG_CMD_VFD * VFD support (TRAB)
668 CFG_CMD_BSP * Board SPecific functions
669 CFG_CMD_CDP * Cisco Discover Protocol support
670 -----------------------------------------------
673 CONFIG_CMD_DFL Default configuration; at the moment
674 this is includes all commands, except
675 the ones marked with "*" in the list
678 If you don't define CONFIG_COMMANDS it defaults to
679 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
680 override the default settings in the respective
683 EXAMPLE: If you want all functions except of network
684 support you can write:
686 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
689 Note: Don't enable the "icache" and "dcache" commands
690 (configuration option CFG_CMD_CACHE) unless you know
691 what you (and your U-Boot users) are doing. Data
692 cache cannot be enabled on systems like the 8xx or
693 8260 (where accesses to the IMMR region must be
694 uncached), and it cannot be disabled on all other
695 systems where we (mis-) use the data cache to hold an
696 initial stack and some data.
699 XXX - this list needs to get updated!
703 If this variable is defined, it enables watchdog
704 support. There must be support in the platform specific
705 code for a watchdog. For the 8xx and 8260 CPUs, the
706 SIU Watchdog feature is enabled in the SYPCR
710 CONFIG_VERSION_VARIABLE
711 If this variable is defined, an environment variable
712 named "ver" is created by U-Boot showing the U-Boot
713 version as printed by the "version" command.
714 This variable is readonly.
718 When CFG_CMD_DATE is selected, the type of the RTC
719 has to be selected, too. Define exactly one of the
722 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
723 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
724 CONFIG_RTC_MC146818 - use MC146818 RTC
725 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
726 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
727 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
728 CONFIG_RTC_DS164x - use Dallas DS164x RTC
729 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
731 Note that if the RTC uses I2C, then the I2C interface
732 must also be configured. See I2C Support, below.
736 When CONFIG_TIMESTAMP is selected, the timestamp
737 (date and time) of an image is printed by image
738 commands like bootm or iminfo. This option is
739 automatically enabled when you select CFG_CMD_DATE .
742 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
743 and/or CONFIG_ISO_PARTITION
745 If IDE or SCSI support is enabled (CFG_CMD_IDE or
746 CFG_CMD_SCSI) you must configure support for at least
747 one partition type as well.
750 CONFIG_IDE_RESET_ROUTINE - this is defined in several
751 board configurations files but used nowhere!
753 CONFIG_IDE_RESET - is this is defined, IDE Reset will
754 be performed by calling the function
755 ide_set_reset(int reset)
756 which has to be defined in a board specific file
761 Set this to enable ATAPI support.
766 Set this to enable support for disks larger than 137GB
767 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
768 Whithout these , LBA48 support uses 32bit variables and will 'only'
769 support disks up to 2.1TB.
772 When enabled, makes the IDE subsystem use 64bit sector addresses.
776 At the moment only there is only support for the
777 SYM53C8XX SCSI controller; define
778 CONFIG_SCSI_SYM53C8XX to enable it.
780 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
781 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
782 CFG_SCSI_MAX_LUN] can be adjusted to define the
783 maximum numbers of LUNs, SCSI ID's and target
785 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
787 - NETWORK Support (PCI):
789 Support for Intel 8254x gigabit chips.
792 Support for Intel 82557/82559/82559ER chips.
793 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
794 write routine for first time initialisation.
797 Support for Digital 2114x chips.
798 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
799 modem chip initialisation (KS8761/QS6611).
802 Support for National dp83815 chips.
805 Support for National dp8382[01] gigabit chips.
807 - NETWORK Support (other):
809 CONFIG_DRIVER_LAN91C96
810 Support for SMSC's LAN91C96 chips.
813 Define this to hold the physical address
814 of the LAN91C96's I/O space
816 CONFIG_LAN91C96_USE_32_BIT
817 Define this to enable 32 bit addressing
819 CONFIG_DRIVER_SMC91111
820 Support for SMSC's LAN91C111 chip
823 Define this to hold the physical address
824 of the device (I/O space)
826 CONFIG_SMC_USE_32_BIT
827 Define this if data bus is 32 bits
829 CONFIG_SMC_USE_IOFUNCS
830 Define this to use i/o functions instead of macros
831 (some hardware wont work with macros)
834 At the moment only the UHCI host controller is
835 supported (PIP405, MIP405, MPC5200); define
836 CONFIG_USB_UHCI to enable it.
837 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
838 and define CONFIG_USB_STORAGE to enable the USB
841 Supported are USB Keyboards and USB Floppy drives
843 MPC5200 USB requires additional defines:
845 for 528 MHz Clock: 0x0001bbbb
847 for differential drivers: 0x00001000
848 for single ended drivers: 0x00005000
852 The MMC controller on the Intel PXA is supported. To
853 enable this define CONFIG_MMC. The MMC can be
854 accessed from the boot prompt by mapping the device
855 to physical memory similar to flash. Command line is
856 enabled with CFG_CMD_MMC. The MMC driver also works with
857 the FAT fs. This is enabled with CFG_CMD_FAT.
859 - Journaling Flash filesystem support:
860 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
861 CONFIG_JFFS2_NAND_DEV
862 Define these for a default partition on a NAND device
864 CFG_JFFS2_FIRST_SECTOR,
865 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
866 Define these for a default partition on a NOR device
869 Define this to create an own partition. You have to provide a
870 function struct part_info* jffs2_part_info(int part_num)
872 If you define only one JFFS2 partition you may also want to
873 #define CFG_JFFS_SINGLE_PART 1
874 to disable the command chpart. This is the default when you
875 have not defined a custom partition
880 Define this to enable standard (PC-Style) keyboard
884 Standard PC keyboard driver with US (is default) and
885 GERMAN key layout (switch via environment 'keymap=de') support.
886 Export function i8042_kbd_init, i8042_tstc and i8042_getc
887 for cfb_console. Supports cursor blinking.
892 Define this to enable video support (for output to
897 Enable Chips & Technologies 69000 Video chip
899 CONFIG_VIDEO_SMI_LYNXEM
900 Enable Silicon Motion SMI 712/710/810 Video chip. The
901 video output is selected via environment 'videoout'
902 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
905 For the CT69000 and SMI_LYNXEM drivers, videomode is
906 selected via environment 'videomode'. Two diferent ways
908 - "videomode=num" 'num' is a standard LiLo mode numbers.
909 Following standard modes are supported (* is default):
911 Colors 640x480 800x600 1024x768 1152x864 1280x1024
912 -------------+---------------------------------------------
913 8 bits | 0x301* 0x303 0x305 0x161 0x307
914 15 bits | 0x310 0x313 0x316 0x162 0x319
915 16 bits | 0x311 0x314 0x317 0x163 0x31A
916 24 bits | 0x312 0x315 0x318 ? 0x31B
917 -------------+---------------------------------------------
918 (i.e. setenv videomode 317; saveenv; reset;)
920 - "videomode=bootargs" all the video parameters are parsed
921 from the bootargs. (See drivers/videomodes.c)
924 CONFIG_VIDEO_SED13806
925 Enable Epson SED13806 driver. This driver supports 8bpp
926 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
927 or CONFIG_VIDEO_SED13806_16BPP
932 Define this to enable a custom keyboard support.
933 This simply calls drv_keyboard_init() which must be
934 defined in your board-specific files.
935 The only board using this so far is RBC823.
937 - LCD Support: CONFIG_LCD
939 Define this to enable LCD support (for output to LCD
940 display); also select one of the supported displays
941 by defining one of these:
943 CONFIG_NEC_NL6448AC33:
945 NEC NL6448AC33-18. Active, color, single scan.
947 CONFIG_NEC_NL6448BC20
949 NEC NL6448BC20-08. 6.5", 640x480.
950 Active, color, single scan.
952 CONFIG_NEC_NL6448BC33_54
954 NEC NL6448BC33-54. 10.4", 640x480.
955 Active, color, single scan.
959 Sharp 320x240. Active, color, single scan.
960 It isn't 16x9, and I am not sure what it is.
962 CONFIG_SHARP_LQ64D341
964 Sharp LQ64D341 display, 640x480.
965 Active, color, single scan.
969 HLD1045 display, 640x480.
970 Active, color, single scan.
974 Optrex CBL50840-2 NF-FW 99 22 M5
976 Hitachi LMG6912RPFC-00T
980 320x240. Black & white.
982 Normally display is black on white background; define
983 CFG_WHITE_ON_BLACK to get it inverted.
985 - Splash Screen Support: CONFIG_SPLASH_SCREEN
987 If this option is set, the environment is checked for
988 a variable "splashimage". If found, the usual display
989 of logo, copyright and system information on the LCD
990 is suppressed and the BMP image at the address
991 specified in "splashimage" is loaded instead. The
992 console is redirected to the "nulldev", too. This
993 allows for a "silent" boot where a splash screen is
994 loaded very quickly after power-on.
996 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
998 If this option is set, additionally to standard BMP
999 images, gzipped BMP images can be displayed via the
1000 splashscreen support or the bmp command.
1002 - Compression support:
1005 If this option is set, support for bzip2 compressed
1006 images is included. If not, only uncompressed and gzip
1007 compressed images are supported.
1009 NOTE: the bzip2 algorithm requires a lot of RAM, so
1010 the malloc area (as defined by CFG_MALLOC_LEN) should
1016 The address of PHY on MII bus.
1018 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1020 The clock frequency of the MII bus
1024 If this option is set, support for speed/duplex
1025 detection of Gigabit PHY is included.
1027 CONFIG_PHY_RESET_DELAY
1029 Some PHY like Intel LXT971A need extra delay after
1030 reset before any MII register access is possible.
1031 For such PHY, set this option to the usec delay
1032 required. (minimum 300usec for LXT971A)
1034 CONFIG_PHY_CMD_DELAY (ppc4xx)
1036 Some PHY like Intel LXT971A need extra delay after
1037 command issued before MII status register can be read
1044 Define a default value for ethernet address to use
1045 for the respective ethernet interface, in case this
1046 is not determined automatically.
1051 Define a default value for the IP address to use for
1052 the default ethernet interface, in case this is not
1053 determined through e.g. bootp.
1055 - Server IP address:
1058 Defines a default value for theIP address of a TFTP
1059 server to contact when using the "tftboot" command.
1061 - BOOTP Recovery Mode:
1062 CONFIG_BOOTP_RANDOM_DELAY
1064 If you have many targets in a network that try to
1065 boot using BOOTP, you may want to avoid that all
1066 systems send out BOOTP requests at precisely the same
1067 moment (which would happen for instance at recovery
1068 from a power failure, when all systems will try to
1069 boot, thus flooding the BOOTP server. Defining
1070 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1071 inserted before sending out BOOTP requests. The
1072 following delays are insterted then:
1074 1st BOOTP request: delay 0 ... 1 sec
1075 2nd BOOTP request: delay 0 ... 2 sec
1076 3rd BOOTP request: delay 0 ... 4 sec
1078 BOOTP requests: delay 0 ... 8 sec
1080 - DHCP Advanced Options:
1083 You can fine tune the DHCP functionality by adding
1084 these flags to the CONFIG_BOOTP_MASK define:
1086 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1087 serverip from a DHCP server, it is possible that more
1088 than one DNS serverip is offered to the client.
1089 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1090 serverip will be stored in the additional environment
1091 variable "dnsip2". The first DNS serverip is always
1092 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1093 is added to the CONFIG_BOOTP_MASK.
1095 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1096 to do a dynamic update of a DNS server. To do this, they
1097 need the hostname of the DHCP requester.
1098 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1099 CONFIG_BOOTP_MASK, the content of the "hostname"
1100 environment variable is passed as option 12 to
1104 CONFIG_CDP_DEVICE_ID
1106 The device id used in CDP trigger frames.
1108 CONFIG_CDP_DEVICE_ID_PREFIX
1110 A two character string which is prefixed to the MAC address
1115 A printf format string which contains the ascii name of
1116 the port. Normally is set to "eth%d" which sets
1117 eth0 for the first ethernet, eth1 for the second etc.
1119 CONFIG_CDP_CAPABILITIES
1121 A 32bit integer which indicates the device capabilities;
1122 0x00000010 for a normal host which does not forwards.
1126 An ascii string containing the version of the software.
1130 An ascii string containing the name of the platform.
1134 A 32bit integer sent on the trigger.
1136 CONFIG_CDP_POWER_CONSUMPTION
1138 A 16bit integer containing the power consumption of the
1139 device in .1 of milliwatts.
1141 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1143 A byte containing the id of the VLAN.
1145 - Status LED: CONFIG_STATUS_LED
1147 Several configurations allow to display the current
1148 status using a LED. For instance, the LED will blink
1149 fast while running U-Boot code, stop blinking as
1150 soon as a reply to a BOOTP request was received, and
1151 start blinking slow once the Linux kernel is running
1152 (supported by a status LED driver in the Linux
1153 kernel). Defining CONFIG_STATUS_LED enables this
1156 - CAN Support: CONFIG_CAN_DRIVER
1158 Defining CONFIG_CAN_DRIVER enables CAN driver support
1159 on those systems that support this (optional)
1160 feature, like the TQM8xxL modules.
1162 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1164 These enable I2C serial bus commands. Defining either of
1165 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1166 include the appropriate I2C driver for the selected cpu.
1168 This will allow you to use i2c commands at the u-boot
1169 command line (as long as you set CFG_CMD_I2C in
1170 CONFIG_COMMANDS) and communicate with i2c based realtime
1171 clock chips. See common/cmd_i2c.c for a description of the
1172 command line interface.
1174 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1176 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1177 bit-banging) driver instead of CPM or similar hardware
1180 There are several other quantities that must also be
1181 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1183 In both cases you will need to define CFG_I2C_SPEED
1184 to be the frequency (in Hz) at which you wish your i2c bus
1185 to run and CFG_I2C_SLAVE to be the address of this node (ie
1186 the cpu's i2c node address).
1188 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1189 sets the cpu up as a master node and so its address should
1190 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1191 p.16-473). So, set CFG_I2C_SLAVE to 0.
1193 That's all that's required for CONFIG_HARD_I2C.
1195 If you use the software i2c interface (CONFIG_SOFT_I2C)
1196 then the following macros need to be defined (examples are
1197 from include/configs/lwmon.h):
1201 (Optional). Any commands necessary to enable the I2C
1202 controller or configure ports.
1204 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1208 (Only for MPC8260 CPU). The I/O port to use (the code
1209 assumes both bits are on the same port). Valid values
1210 are 0..3 for ports A..D.
1214 The code necessary to make the I2C data line active
1215 (driven). If the data line is open collector, this
1218 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1222 The code necessary to make the I2C data line tri-stated
1223 (inactive). If the data line is open collector, this
1226 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1230 Code that returns TRUE if the I2C data line is high,
1233 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1237 If <bit> is TRUE, sets the I2C data line high. If it
1238 is FALSE, it clears it (low).
1240 eg: #define I2C_SDA(bit) \
1241 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1242 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1246 If <bit> is TRUE, sets the I2C clock line high. If it
1247 is FALSE, it clears it (low).
1249 eg: #define I2C_SCL(bit) \
1250 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1251 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1255 This delay is invoked four times per clock cycle so this
1256 controls the rate of data transfer. The data rate thus
1257 is 1 / (I2C_DELAY * 4). Often defined to be something
1260 #define I2C_DELAY udelay(2)
1264 When a board is reset during an i2c bus transfer
1265 chips might think that the current transfer is still
1266 in progress. On some boards it is possible to access
1267 the i2c SCLK line directly, either by using the
1268 processor pin as a GPIO or by having a second pin
1269 connected to the bus. If this option is defined a
1270 custom i2c_init_board() routine in boards/xxx/board.c
1271 is run early in the boot sequence.
1273 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1275 This option enables configuration of bi_iic_fast[] flags
1276 in u-boot bd_info structure based on u-boot environment
1277 variable "i2cfast". (see also i2cfast)
1279 - SPI Support: CONFIG_SPI
1281 Enables SPI driver (so far only tested with
1282 SPI EEPROM, also an instance works with Crystal A/D and
1283 D/As on the SACSng board)
1287 Enables extended (16-bit) SPI EEPROM addressing.
1288 (symmetrical to CONFIG_I2C_X)
1292 Enables a software (bit-bang) SPI driver rather than
1293 using hardware support. This is a general purpose
1294 driver that only requires three general I/O port pins
1295 (two outputs, one input) to function. If this is
1296 defined, the board configuration must define several
1297 SPI configuration items (port pins to use, etc). For
1298 an example, see include/configs/sacsng.h.
1300 - FPGA Support: CONFIG_FPGA_COUNT
1302 Specify the number of FPGA devices to support.
1306 Used to specify the types of FPGA devices. For example,
1307 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1309 CFG_FPGA_PROG_FEEDBACK
1311 Enable printing of hash marks during FPGA configuration.
1315 Enable checks on FPGA configuration interface busy
1316 status by the configuration function. This option
1317 will require a board or device specific function to
1322 If defined, a function that provides delays in the FPGA
1323 configuration driver.
1325 CFG_FPGA_CHECK_CTRLC
1326 Allow Control-C to interrupt FPGA configuration
1328 CFG_FPGA_CHECK_ERROR
1330 Check for configuration errors during FPGA bitfile
1331 loading. For example, abort during Virtex II
1332 configuration if the INIT_B line goes low (which
1333 indicated a CRC error).
1337 Maximum time to wait for the INIT_B line to deassert
1338 after PROB_B has been deasserted during a Virtex II
1339 FPGA configuration sequence. The default time is 500
1344 Maximum time to wait for BUSY to deassert during
1345 Virtex II FPGA configuration. The default is 5 mS.
1347 CFG_FPGA_WAIT_CONFIG
1349 Time to wait after FPGA configuration. The default is
1352 - Configuration Management:
1355 If defined, this string will be added to the U-Boot
1356 version information (U_BOOT_VERSION)
1358 - Vendor Parameter Protection:
1360 U-Boot considers the values of the environment
1361 variables "serial#" (Board Serial Number) and
1362 "ethaddr" (Ethernet Address) to be parameters that
1363 are set once by the board vendor / manufacturer, and
1364 protects these variables from casual modification by
1365 the user. Once set, these variables are read-only,
1366 and write or delete attempts are rejected. You can
1367 change this behviour:
1369 If CONFIG_ENV_OVERWRITE is #defined in your config
1370 file, the write protection for vendor parameters is
1371 completely disabled. Anybody can change or delete
1374 Alternatively, if you #define _both_ CONFIG_ETHADDR
1375 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1376 ethernet address is installed in the environment,
1377 which can be changed exactly ONCE by the user. [The
1378 serial# is unaffected by this, i. e. it remains
1384 Define this variable to enable the reservation of
1385 "protected RAM", i. e. RAM which is not overwritten
1386 by U-Boot. Define CONFIG_PRAM to hold the number of
1387 kB you want to reserve for pRAM. You can overwrite
1388 this default value by defining an environment
1389 variable "pram" to the number of kB you want to
1390 reserve. Note that the board info structure will
1391 still show the full amount of RAM. If pRAM is
1392 reserved, a new environment variable "mem" will
1393 automatically be defined to hold the amount of
1394 remaining RAM in a form that can be passed as boot
1395 argument to Linux, for instance like that:
1397 setenv bootargs ... mem=\${mem}
1400 This way you can tell Linux not to use this memory,
1401 either, which results in a memory region that will
1402 not be affected by reboots.
1404 *WARNING* If your board configuration uses automatic
1405 detection of the RAM size, you must make sure that
1406 this memory test is non-destructive. So far, the
1407 following board configurations are known to be
1410 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1411 HERMES, IP860, RPXlite, LWMON, LANTEC,
1412 PCU_E, FLAGADM, TQM8260
1417 Define this variable to stop the system in case of a
1418 fatal error, so that you have to reset it manually.
1419 This is probably NOT a good idea for an embedded
1420 system where you want to system to reboot
1421 automatically as fast as possible, but it may be
1422 useful during development since you can try to debug
1423 the conditions that lead to the situation.
1425 CONFIG_NET_RETRY_COUNT
1427 This variable defines the number of retries for
1428 network operations like ARP, RARP, TFTP, or BOOTP
1429 before giving up the operation. If not defined, a
1430 default value of 5 is used.
1432 - Command Interpreter:
1435 Enable auto completion of commands using TAB.
1439 Define this variable to enable the "hush" shell (from
1440 Busybox) as command line interpreter, thus enabling
1441 powerful command line syntax like
1442 if...then...else...fi conditionals or `&&' and '||'
1443 constructs ("shell scripts").
1445 If undefined, you get the old, much simpler behaviour
1446 with a somewhat smaller memory footprint.
1451 This defines the secondary prompt string, which is
1452 printed when the command interpreter needs more input
1453 to complete a command. Usually "> ".
1457 In the current implementation, the local variables
1458 space and global environment variables space are
1459 separated. Local variables are those you define by
1460 simply typing `name=value'. To access a local
1461 variable later on, you have write `$name' or
1462 `${name}'; to execute the contents of a variable
1463 directly type `$name' at the command prompt.
1465 Global environment variables are those you use
1466 setenv/printenv to work with. To run a command stored
1467 in such a variable, you need to use the run command,
1468 and you must not use the '$' sign to access them.
1470 To store commands and special characters in a
1471 variable, please use double quotation marks
1472 surrounding the whole text of the variable, instead
1473 of the backslashes before semicolons and special
1476 - Default Environment:
1477 CONFIG_EXTRA_ENV_SETTINGS
1479 Define this to contain any number of null terminated
1480 strings (variable = value pairs) that will be part of
1481 the default environment compiled into the boot image.
1483 For example, place something like this in your
1484 board's config file:
1486 #define CONFIG_EXTRA_ENV_SETTINGS \
1490 Warning: This method is based on knowledge about the
1491 internal format how the environment is stored by the
1492 U-Boot code. This is NOT an official, exported
1493 interface! Although it is unlikely that this format
1494 will change soon, there is no guarantee either.
1495 You better know what you are doing here.
1497 Note: overly (ab)use of the default environment is
1498 discouraged. Make sure to check other ways to preset
1499 the environment like the autoscript function or the
1502 - DataFlash Support:
1503 CONFIG_HAS_DATAFLASH
1505 Defining this option enables DataFlash features and
1506 allows to read/write in Dataflash via the standard
1509 - SystemACE Support:
1512 Adding this option adds support for Xilinx SystemACE
1513 chips attached via some sort of local bus. The address
1514 of the chip must alsh be defined in the
1515 CFG_SYSTEMACE_BASE macro. For example:
1517 #define CONFIG_SYSTEMACE
1518 #define CFG_SYSTEMACE_BASE 0xf0000000
1520 When SystemACE support is added, the "ace" device type
1521 becomes available to the fat commands, i.e. fatls.
1523 - TFTP Fixed UDP Port:
1526 If this is defined, the environment variable tftpsrcp
1527 is used to supply the TFTP UDP source port value.
1528 If tftpsrcp isn't defined, the normal pseudo-random port
1529 number generator is used.
1531 Also, the environment variable tftpdstp is used to supply
1532 the TFTP UDP destination port value. If tftpdstp isn't
1533 defined, the normal port 69 is used.
1535 The purpose for tftpsrcp is to allow a TFTP server to
1536 blindly start the TFTP transfer using the pre-configured
1537 target IP address and UDP port. This has the effect of
1538 "punching through" the (Windows XP) firewall, allowing
1539 the remainder of the TFTP transfer to proceed normally.
1540 A better solution is to properly configure the firewall,
1541 but sometimes that is not allowed.
1543 - Show boot progress:
1544 CONFIG_SHOW_BOOT_PROGRESS
1546 Defining this option allows to add some board-
1547 specific code (calling a user-provided function
1548 "show_boot_progress(int)") that enables you to show
1549 the system's boot progress on some display (for
1550 example, some LED's) on your board. At the moment,
1551 the following checkpoints are implemented:
1554 1 common/cmd_bootm.c before attempting to boot an image
1555 -1 common/cmd_bootm.c Image header has bad magic number
1556 2 common/cmd_bootm.c Image header has correct magic number
1557 -2 common/cmd_bootm.c Image header has bad checksum
1558 3 common/cmd_bootm.c Image header has correct checksum
1559 -3 common/cmd_bootm.c Image data has bad checksum
1560 4 common/cmd_bootm.c Image data has correct checksum
1561 -4 common/cmd_bootm.c Image is for unsupported architecture
1562 5 common/cmd_bootm.c Architecture check OK
1563 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1564 6 common/cmd_bootm.c Image Type check OK
1565 -6 common/cmd_bootm.c gunzip uncompression error
1566 -7 common/cmd_bootm.c Unimplemented compression type
1567 7 common/cmd_bootm.c Uncompression OK
1568 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1569 8 common/cmd_bootm.c Image Type check OK
1570 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1571 9 common/cmd_bootm.c Start initial ramdisk verification
1572 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1573 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1574 10 common/cmd_bootm.c Ramdisk header is OK
1575 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1576 11 common/cmd_bootm.c Ramdisk data has correct checksum
1577 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1578 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1579 13 common/cmd_bootm.c Start multifile image verification
1580 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1581 15 common/cmd_bootm.c All preparation done, transferring control to OS
1583 -30 lib_ppc/board.c Fatal error, hang the system
1584 -31 post/post.c POST test failed, detected by post_output_backlog()
1585 -32 post/post.c POST test failed, detected by post_run_single()
1587 -1 common/cmd_doc.c Bad usage of "doc" command
1588 -1 common/cmd_doc.c No boot device
1589 -1 common/cmd_doc.c Unknown Chip ID on boot device
1590 -1 common/cmd_doc.c Read Error on boot device
1591 -1 common/cmd_doc.c Image header has bad magic number
1593 -1 common/cmd_ide.c Bad usage of "ide" command
1594 -1 common/cmd_ide.c No boot device
1595 -1 common/cmd_ide.c Unknown boot device
1596 -1 common/cmd_ide.c Unknown partition table
1597 -1 common/cmd_ide.c Invalid partition type
1598 -1 common/cmd_ide.c Read Error on boot device
1599 -1 common/cmd_ide.c Image header has bad magic number
1601 -1 common/cmd_nand.c Bad usage of "nand" command
1602 -1 common/cmd_nand.c No boot device
1603 -1 common/cmd_nand.c Unknown Chip ID on boot device
1604 -1 common/cmd_nand.c Read Error on boot device
1605 -1 common/cmd_nand.c Image header has bad magic number
1607 -1 common/env_common.c Environment has a bad CRC, using default
1613 [so far only for SMDK2400 and TRAB boards]
1615 - Modem support endable:
1616 CONFIG_MODEM_SUPPORT
1618 - RTS/CTS Flow control enable:
1621 - Modem debug support:
1622 CONFIG_MODEM_SUPPORT_DEBUG
1624 Enables debugging stuff (char screen[1024], dbg())
1625 for modem support. Useful only with BDI2000.
1627 - Interrupt support (PPC):
1629 There are common interrupt_init() and timer_interrupt()
1630 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1631 for cpu specific initialization. interrupt_init_cpu()
1632 should set decrementer_count to appropriate value. If
1633 cpu resets decrementer automatically after interrupt
1634 (ppc4xx) it should set decrementer_count to zero.
1635 timer_interrupt() calls timer_interrupt_cpu() for cpu
1636 specific handling. If board has watchdog / status_led
1637 / other_activity_monitor it works automatically from
1638 general timer_interrupt().
1642 In the target system modem support is enabled when a
1643 specific key (key combination) is pressed during
1644 power-on. Otherwise U-Boot will boot normally
1645 (autoboot). The key_pressed() fuction is called from
1646 board_init(). Currently key_pressed() is a dummy
1647 function, returning 1 and thus enabling modem
1650 If there are no modem init strings in the
1651 environment, U-Boot proceed to autoboot; the
1652 previous output (banner, info printfs) will be
1655 See also: doc/README.Modem
1658 Configuration Settings:
1659 -----------------------
1661 - CFG_LONGHELP: Defined when you want long help messages included;
1662 undefine this when you're short of memory.
1664 - CFG_PROMPT: This is what U-Boot prints on the console to
1665 prompt for user input.
1667 - CFG_CBSIZE: Buffer size for input from the Console
1669 - CFG_PBSIZE: Buffer size for Console output
1671 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1673 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1674 the application (usually a Linux kernel) when it is
1677 - CFG_BAUDRATE_TABLE:
1678 List of legal baudrate settings for this board.
1680 - CFG_CONSOLE_INFO_QUIET
1681 Suppress display of console information at boot.
1683 - CFG_CONSOLE_IS_IN_ENV
1684 If the board specific function
1685 extern int overwrite_console (void);
1686 returns 1, the stdin, stderr and stdout are switched to the
1687 serial port, else the settings in the environment are used.
1689 - CFG_CONSOLE_OVERWRITE_ROUTINE
1690 Enable the call to overwrite_console().
1692 - CFG_CONSOLE_ENV_OVERWRITE
1693 Enable overwrite of previous console environment settings.
1695 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1696 Begin and End addresses of the area used by the
1700 Enable an alternate, more extensive memory test.
1702 - CFG_MEMTEST_SCRATCH:
1703 Scratch address used by the alternate memory test
1704 You only need to set this if address zero isn't writeable
1706 - CFG_TFTP_LOADADDR:
1707 Default load address for network file downloads
1709 - CFG_LOADS_BAUD_CHANGE:
1710 Enable temporary baudrate change while serial download
1713 Physical start address of SDRAM. _Must_ be 0 here.
1716 Physical start address of Motherboard I/O (if using a
1720 Physical start address of Flash memory.
1723 Physical start address of boot monitor code (set by
1724 make config files to be same as the text base address
1725 (TEXT_BASE) used when linking) - same as
1726 CFG_FLASH_BASE when booting from flash.
1729 Size of memory reserved for monitor code, used to
1730 determine _at_compile_time_ (!) if the environment is
1731 embedded within the U-Boot image, or in a separate
1735 Size of DRAM reserved for malloc() use.
1738 Maximum size of memory mapped by the startup code of
1739 the Linux kernel; all data that must be processed by
1740 the Linux kernel (bd_info, boot arguments, eventually
1741 initrd image) must be put below this limit.
1743 - CFG_MAX_FLASH_BANKS:
1744 Max number of Flash memory banks
1746 - CFG_MAX_FLASH_SECT:
1747 Max number of sectors on a Flash chip
1749 - CFG_FLASH_ERASE_TOUT:
1750 Timeout for Flash erase operations (in ms)
1752 - CFG_FLASH_WRITE_TOUT:
1753 Timeout for Flash write operations (in ms)
1755 - CFG_FLASH_LOCK_TOUT
1756 Timeout for Flash set sector lock bit operation (in ms)
1758 - CFG_FLASH_UNLOCK_TOUT
1759 Timeout for Flash clear lock bits operation (in ms)
1761 - CFG_FLASH_PROTECTION
1762 If defined, hardware flash sectors protection is used
1763 instead of U-Boot software protection.
1765 - CFG_DIRECT_FLASH_TFTP:
1767 Enable TFTP transfers directly to flash memory;
1768 without this option such a download has to be
1769 performed in two steps: (1) download to RAM, and (2)
1770 copy from RAM to flash.
1772 The two-step approach is usually more reliable, since
1773 you can check if the download worked before you erase
1774 the flash, but in some situations (when sytem RAM is
1775 too limited to allow for a tempory copy of the
1776 downloaded image) this option may be very useful.
1779 Define if the flash driver uses extra elements in the
1780 common flash structure for storing flash geometry.
1782 - CFG_FLASH_CFI_DRIVER
1783 This option also enables the building of the cfi_flash driver
1784 in the drivers directory
1786 - CFG_FLASH_QUIET_TEST
1787 If this option is defined, the common CFI flash doesn't
1788 print it's warning upon not recognized FLASH banks. This
1789 is useful, if some of the configured banks are only
1790 optionally available.
1792 - CFG_RX_ETH_BUFFER:
1793 Defines the number of ethernet receive buffers. On some
1794 ethernet controllers it is recommended to set this value
1795 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1796 buffers can be full shortly after enabling the interface
1797 on high ethernet traffic.
1798 Defaults to 4 if not defined.
1800 The following definitions that deal with the placement and management
1801 of environment data (variable area); in general, we support the
1802 following configurations:
1804 - CFG_ENV_IS_IN_FLASH:
1806 Define this if the environment is in flash memory.
1808 a) The environment occupies one whole flash sector, which is
1809 "embedded" in the text segment with the U-Boot code. This
1810 happens usually with "bottom boot sector" or "top boot
1811 sector" type flash chips, which have several smaller
1812 sectors at the start or the end. For instance, such a
1813 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1814 such a case you would place the environment in one of the
1815 4 kB sectors - with U-Boot code before and after it. With
1816 "top boot sector" type flash chips, you would put the
1817 environment in one of the last sectors, leaving a gap
1818 between U-Boot and the environment.
1822 Offset of environment data (variable area) to the
1823 beginning of flash memory; for instance, with bottom boot
1824 type flash chips the second sector can be used: the offset
1825 for this sector is given here.
1827 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1831 This is just another way to specify the start address of
1832 the flash sector containing the environment (instead of
1835 - CFG_ENV_SECT_SIZE:
1837 Size of the sector containing the environment.
1840 b) Sometimes flash chips have few, equal sized, BIG sectors.
1841 In such a case you don't want to spend a whole sector for
1846 If you use this in combination with CFG_ENV_IS_IN_FLASH
1847 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1848 of this flash sector for the environment. This saves
1849 memory for the RAM copy of the environment.
1851 It may also save flash memory if you decide to use this
1852 when your environment is "embedded" within U-Boot code,
1853 since then the remainder of the flash sector could be used
1854 for U-Boot code. It should be pointed out that this is
1855 STRONGLY DISCOURAGED from a robustness point of view:
1856 updating the environment in flash makes it always
1857 necessary to erase the WHOLE sector. If something goes
1858 wrong before the contents has been restored from a copy in
1859 RAM, your target system will be dead.
1861 - CFG_ENV_ADDR_REDUND
1864 These settings describe a second storage area used to hold
1865 a redundand copy of the environment data, so that there is
1866 a valid backup copy in case there is a power failure during
1867 a "saveenv" operation.
1869 BE CAREFUL! Any changes to the flash layout, and some changes to the
1870 source code will make it necessary to adapt <board>/u-boot.lds*
1874 - CFG_ENV_IS_IN_NVRAM:
1876 Define this if you have some non-volatile memory device
1877 (NVRAM, battery buffered SRAM) which you want to use for the
1883 These two #defines are used to determin the memory area you
1884 want to use for environment. It is assumed that this memory
1885 can just be read and written to, without any special
1888 BE CAREFUL! The first access to the environment happens quite early
1889 in U-Boot initalization (when we try to get the setting of for the
1890 console baudrate). You *MUST* have mappend your NVRAM area then, or
1893 Please note that even with NVRAM we still use a copy of the
1894 environment in RAM: we could work on NVRAM directly, but we want to
1895 keep settings there always unmodified except somebody uses "saveenv"
1896 to save the current settings.
1899 - CFG_ENV_IS_IN_EEPROM:
1901 Use this if you have an EEPROM or similar serial access
1902 device and a driver for it.
1907 These two #defines specify the offset and size of the
1908 environment area within the total memory of your EEPROM.
1910 - CFG_I2C_EEPROM_ADDR:
1911 If defined, specified the chip address of the EEPROM device.
1912 The default address is zero.
1914 - CFG_EEPROM_PAGE_WRITE_BITS:
1915 If defined, the number of bits used to address bytes in a
1916 single page in the EEPROM device. A 64 byte page, for example
1917 would require six bits.
1919 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1920 If defined, the number of milliseconds to delay between
1921 page writes. The default is zero milliseconds.
1923 - CFG_I2C_EEPROM_ADDR_LEN:
1924 The length in bytes of the EEPROM memory array address. Note
1925 that this is NOT the chip address length!
1927 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1928 EEPROM chips that implement "address overflow" are ones
1929 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1930 address and the extra bits end up in the "chip address" bit
1931 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1934 Note that we consider the length of the address field to
1935 still be one byte because the extra address bits are hidden
1936 in the chip address.
1939 The size in bytes of the EEPROM device.
1942 - CFG_ENV_IS_IN_DATAFLASH:
1944 Define this if you have a DataFlash memory device which you
1945 want to use for the environment.
1951 These three #defines specify the offset and size of the
1952 environment area within the total memory of your DataFlash placed
1953 at the specified address.
1955 - CFG_ENV_IS_IN_NAND:
1957 Define this if you have a NAND device which you want to use
1958 for the environment.
1963 These two #defines specify the offset and size of the environment
1964 area within the first NAND device.
1966 - CFG_SPI_INIT_OFFSET
1968 Defines offset to the initial SPI buffer area in DPRAM. The
1969 area is used at an early stage (ROM part) if the environment
1970 is configured to reside in the SPI EEPROM: We need a 520 byte
1971 scratch DPRAM area. It is used between the two initialization
1972 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1973 to be a good choice since it makes it far enough from the
1974 start of the data area as well as from the stack pointer.
1976 Please note that the environment is read-only as long as the monitor
1977 has been relocated to RAM and a RAM copy of the environment has been
1978 created; also, when using EEPROM you will have to use getenv_r()
1979 until then to read environment variables.
1981 The environment is protected by a CRC32 checksum. Before the monitor
1982 is relocated into RAM, as a result of a bad CRC you will be working
1983 with the compiled-in default environment - *silently*!!! [This is
1984 necessary, because the first environment variable we need is the
1985 "baudrate" setting for the console - if we have a bad CRC, we don't
1986 have any device yet where we could complain.]
1988 Note: once the monitor has been relocated, then it will complain if
1989 the default environment is used; a new CRC is computed as soon as you
1990 use the "saveenv" command to store a valid environment.
1992 - CFG_FAULT_ECHO_LINK_DOWN:
1993 Echo the inverted Ethernet link state to the fault LED.
1995 Note: If this option is active, then CFG_FAULT_MII_ADDR
1996 also needs to be defined.
1998 - CFG_FAULT_MII_ADDR:
1999 MII address of the PHY to check for the Ethernet link state.
2001 - CFG_64BIT_VSPRINTF:
2002 Makes vsprintf (and all *printf functions) support printing
2003 of 64bit values by using the L quantifier
2005 - CFG_64BIT_STRTOUL:
2006 Adds simple_strtoull that returns a 64bit value
2008 Low Level (hardware related) configuration options:
2009 ---------------------------------------------------
2011 - CFG_CACHELINE_SIZE:
2012 Cache Line Size of the CPU.
2015 Default address of the IMMR after system reset.
2017 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2018 and RPXsuper) to be able to adjust the position of
2019 the IMMR register after a reset.
2021 - Floppy Disk Support:
2022 CFG_FDC_DRIVE_NUMBER
2024 the default drive number (default value 0)
2028 defines the spacing between fdc chipset registers
2033 defines the offset of register from address. It
2034 depends on which part of the data bus is connected to
2035 the fdc chipset. (default value 0)
2037 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2038 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2041 if CFG_FDC_HW_INIT is defined, then the function
2042 fdc_hw_init() is called at the beginning of the FDC
2043 setup. fdc_hw_init() must be provided by the board
2044 source code. It is used to make hardware dependant
2047 - CFG_IMMR: Physical address of the Internal Memory.
2048 DO NOT CHANGE unless you know exactly what you're
2049 doing! (11-4) [MPC8xx/82xx systems only]
2051 - CFG_INIT_RAM_ADDR:
2053 Start address of memory area that can be used for
2054 initial data and stack; please note that this must be
2055 writable memory that is working WITHOUT special
2056 initialization, i. e. you CANNOT use normal RAM which
2057 will become available only after programming the
2058 memory controller and running certain initialization
2061 U-Boot uses the following memory types:
2062 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2063 - MPC824X: data cache
2064 - PPC4xx: data cache
2066 - CFG_GBL_DATA_OFFSET:
2068 Offset of the initial data structure in the memory
2069 area defined by CFG_INIT_RAM_ADDR. Usually
2070 CFG_GBL_DATA_OFFSET is chosen such that the initial
2071 data is located at the end of the available space
2072 (sometimes written as (CFG_INIT_RAM_END -
2073 CFG_INIT_DATA_SIZE), and the initial stack is just
2074 below that area (growing from (CFG_INIT_RAM_ADDR +
2075 CFG_GBL_DATA_OFFSET) downward.
2078 On the MPC824X (or other systems that use the data
2079 cache for initial memory) the address chosen for
2080 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2081 point to an otherwise UNUSED address space between
2082 the top of RAM and the start of the PCI space.
2084 - CFG_SIUMCR: SIU Module Configuration (11-6)
2086 - CFG_SYPCR: System Protection Control (11-9)
2088 - CFG_TBSCR: Time Base Status and Control (11-26)
2090 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2092 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2094 - CFG_SCCR: System Clock and reset Control Register (15-27)
2096 - CFG_OR_TIMING_SDRAM:
2100 periodic timer for refresh
2102 - CFG_DER: Debug Event Register (37-47)
2104 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2105 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2106 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2108 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2110 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2111 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2112 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2113 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2115 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2116 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2117 Machine Mode Register and Memory Periodic Timer
2118 Prescaler definitions (SDRAM timing)
2120 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2121 enable I2C microcode relocation patch (MPC8xx);
2122 define relocation offset in DPRAM [DSP2]
2124 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2125 enable SPI microcode relocation patch (MPC8xx);
2126 define relocation offset in DPRAM [SCC4]
2129 Use OSCM clock mode on MBX8xx board. Be careful,
2130 wrong setting might damage your board. Read
2131 doc/README.MBX before setting this variable!
2133 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2134 Offset of the bootmode word in DPRAM used by post
2135 (Power On Self Tests). This definition overrides
2136 #define'd default value in commproc.h resp.
2139 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2140 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2141 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2142 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2143 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2144 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2145 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2146 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2147 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2149 - CONFIG_ETHER_ON_FEC[12]
2150 Define to enable FEC[12] on a 8xx series processor.
2152 - CONFIG_FEC[12]_PHY
2153 Define to the hardcoded PHY address which corresponds
2154 to the given FEC; i. e.
2155 #define CONFIG_FEC1_PHY 4
2156 means that the PHY with address 4 is connected to FEC1
2158 When set to -1, means to probe for first available.
2160 - CONFIG_FEC[12]_PHY_NORXERR
2161 The PHY does not have a RXERR line (RMII only).
2162 (so program the FEC to ignore it).
2165 Enable RMII mode for all FECs.
2166 Note that this is a global option, we can't
2167 have one FEC in standard MII mode and another in RMII mode.
2169 - CONFIG_CRC32_VERIFY
2170 Add a verify option to the crc32 command.
2173 => crc32 -v <address> <count> <crc32>
2175 Where address/count indicate a memory area
2176 and crc32 is the correct crc32 which the
2180 Add the "loopw" memory command. This only takes effect if
2181 the memory commands are activated globally (CFG_CMD_MEM).
2184 Add the "mdc" and "mwc" memory commands. These are cyclic
2189 This command will print 4 bytes (10,11,12,13) each 500 ms.
2191 => mwc.l 100 12345678 10
2192 This command will write 12345678 to address 100 all 10 ms.
2194 This only takes effect if the memory commands are activated
2195 globally (CFG_CMD_MEM).
2197 - CONFIG_SKIP_LOWLEVEL_INIT
2198 - CONFIG_SKIP_RELOCATE_UBOOT
2200 [ARM only] If these variables are defined, then
2201 certain low level initializations (like setting up
2202 the memory controller) are omitted and/or U-Boot does
2203 not relocate itself into RAM.
2204 Normally these variables MUST NOT be defined. The
2205 only exception is when U-Boot is loaded (to RAM) by
2206 some other boot loader or by a debugger which
2207 performs these intializations itself.
2210 Building the Software:
2211 ======================
2213 Building U-Boot has been tested in native PPC environments (on a
2214 PowerBook G3 running LinuxPPC 2000) and in cross environments
2215 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2218 If you are not using a native PPC environment, it is assumed that you
2219 have the GNU cross compiling tools available in your path and named
2220 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2221 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2222 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2225 CROSS_COMPILE = ppc_4xx-
2228 U-Boot is intended to be simple to build. After installing the
2229 sources you must configure U-Boot for one specific board type. This
2234 where "NAME_config" is the name of one of the existing
2235 configurations; the following names are supported:
2237 ADCIOP_config FPS860L_config omap730p2_config
2238 ADS860_config GEN860T_config pcu_e_config
2240 AR405_config GENIETV_config PIP405_config
2241 at91rm9200dk_config GTH_config QS823_config
2242 CANBT_config hermes_config QS850_config
2243 cmi_mpc5xx_config hymod_config QS860T_config
2244 cogent_common_config IP860_config RPXlite_config
2245 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2246 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2247 CPCI405_config JSE_config rsdproto_config
2248 CPCIISER4_config LANTEC_config Sandpoint8240_config
2249 csb272_config lwmon_config sbc8260_config
2250 CU824_config MBX860T_config sbc8560_33_config
2251 DUET_ADS_config MBX_config sbc8560_66_config
2252 EBONY_config MPC8260ADS_config SM850_config
2253 ELPT860_config MPC8540ADS_config SPD823TS_config
2254 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2255 ETX094_config MPC8560ADS_config SXNI855T_config
2256 FADS823_config NETVIA_config TQM823L_config
2257 FADS850SAR_config omap1510inn_config TQM850L_config
2258 FADS860T_config omap1610h2_config TQM855L_config
2259 FPS850L_config omap1610inn_config TQM860L_config
2260 omap5912osk_config walnut_config
2261 omap2420h4_config Yukon8220_config
2264 Note: for some board special configuration names may exist; check if
2265 additional information is available from the board vendor; for
2266 instance, the TQM823L systems are available without (standard)
2267 or with LCD support. You can select such additional "features"
2268 when chosing the configuration, i. e.
2271 - will configure for a plain TQM823L, i. e. no LCD support
2273 make TQM823L_LCD_config
2274 - will configure for a TQM823L with U-Boot console on LCD
2279 Finally, type "make all", and you should get some working U-Boot
2280 images ready for download to / installation on your system:
2282 - "u-boot.bin" is a raw binary image
2283 - "u-boot" is an image in ELF binary format
2284 - "u-boot.srec" is in Motorola S-Record format
2287 Please be aware that the Makefiles assume you are using GNU make, so
2288 for instance on NetBSD you might need to use "gmake" instead of
2292 If the system board that you have is not listed, then you will need
2293 to port U-Boot to your hardware platform. To do this, follow these
2296 1. Add a new configuration option for your board to the toplevel
2297 "Makefile" and to the "MAKEALL" script, using the existing
2298 entries as examples. Note that here and at many other places
2299 boards and other names are listed in alphabetical sort order. Please
2301 2. Create a new directory to hold your board specific code. Add any
2302 files you need. In your board directory, you will need at least
2303 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2304 3. Create a new configuration file "include/configs/<board>.h" for
2306 3. If you're porting U-Boot to a new CPU, then also create a new
2307 directory to hold your CPU specific code. Add any files you need.
2308 4. Run "make <board>_config" with your new name.
2309 5. Type "make", and you should get a working "u-boot.srec" file
2310 to be installed on your target system.
2311 6. Debug and solve any problems that might arise.
2312 [Of course, this last step is much harder than it sounds.]
2315 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2316 ==============================================================
2318 If you have modified U-Boot sources (for instance added a new board
2319 or support for new devices, a new CPU, etc.) you are expected to
2320 provide feedback to the other developers. The feedback normally takes
2321 the form of a "patch", i. e. a context diff against a certain (latest
2322 official or latest in CVS) version of U-Boot sources.
2324 But before you submit such a patch, please verify that your modifi-
2325 cation did not break existing code. At least make sure that *ALL* of
2326 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2327 just run the "MAKEALL" script, which will configure and build U-Boot
2328 for ALL supported system. Be warned, this will take a while. You can
2329 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2330 environment variable to the script, i. e. to use the cross tools from
2331 MontaVista's Hard Hat Linux you can type
2333 CROSS_COMPILE=ppc_8xx- MAKEALL
2335 or to build on a native PowerPC system you can type
2337 CROSS_COMPILE=' ' MAKEALL
2339 See also "U-Boot Porting Guide" below.
2342 Monitor Commands - Overview:
2343 ============================
2345 go - start application at address 'addr'
2346 run - run commands in an environment variable
2347 bootm - boot application image from memory
2348 bootp - boot image via network using BootP/TFTP protocol
2349 tftpboot- boot image via network using TFTP protocol
2350 and env variables "ipaddr" and "serverip"
2351 (and eventually "gatewayip")
2352 rarpboot- boot image via network using RARP/TFTP protocol
2353 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2354 loads - load S-Record file over serial line
2355 loadb - load binary file over serial line (kermit mode)
2357 mm - memory modify (auto-incrementing)
2358 nm - memory modify (constant address)
2359 mw - memory write (fill)
2361 cmp - memory compare
2362 crc32 - checksum calculation
2363 imd - i2c memory display
2364 imm - i2c memory modify (auto-incrementing)
2365 inm - i2c memory modify (constant address)
2366 imw - i2c memory write (fill)
2367 icrc32 - i2c checksum calculation
2368 iprobe - probe to discover valid I2C chip addresses
2369 iloop - infinite loop on address range
2370 isdram - print SDRAM configuration information
2371 sspi - SPI utility commands
2372 base - print or set address offset
2373 printenv- print environment variables
2374 setenv - set environment variables
2375 saveenv - save environment variables to persistent storage
2376 protect - enable or disable FLASH write protection
2377 erase - erase FLASH memory
2378 flinfo - print FLASH memory information
2379 bdinfo - print Board Info structure
2380 iminfo - print header information for application image
2381 coninfo - print console devices and informations
2382 ide - IDE sub-system
2383 loop - infinite loop on address range
2384 loopw - infinite write loop on address range
2385 mtest - simple RAM test
2386 icache - enable or disable instruction cache
2387 dcache - enable or disable data cache
2388 reset - Perform RESET of the CPU
2389 echo - echo args to console
2390 version - print monitor version
2391 help - print online help
2392 ? - alias for 'help'
2395 Monitor Commands - Detailed Description:
2396 ========================================
2400 For now: just type "help <command>".
2403 Environment Variables:
2404 ======================
2406 U-Boot supports user configuration using Environment Variables which
2407 can be made persistent by saving to Flash memory.
2409 Environment Variables are set using "setenv", printed using
2410 "printenv", and saved to Flash using "saveenv". Using "setenv"
2411 without a value can be used to delete a variable from the
2412 environment. As long as you don't save the environment you are
2413 working with an in-memory copy. In case the Flash area containing the
2414 environment is erased by accident, a default environment is provided.
2416 Some configuration options can be set using Environment Variables:
2418 baudrate - see CONFIG_BAUDRATE
2420 bootdelay - see CONFIG_BOOTDELAY
2422 bootcmd - see CONFIG_BOOTCOMMAND
2424 bootargs - Boot arguments when booting an RTOS image
2426 bootfile - Name of the image to load with TFTP
2428 autoload - if set to "no" (any string beginning with 'n'),
2429 "bootp" will just load perform a lookup of the
2430 configuration from the BOOTP server, but not try to
2431 load any image using TFTP
2433 autostart - if set to "yes", an image loaded using the "bootp",
2434 "rarpboot", "tftpboot" or "diskboot" commands will
2435 be automatically started (by internally calling
2438 If set to "no", a standalone image passed to the
2439 "bootm" command will be copied to the load address
2440 (and eventually uncompressed), but NOT be started.
2441 This can be used to load and uncompress arbitrary
2444 i2cfast - (PPC405GP|PPC405EP only)
2445 if set to 'y' configures Linux I2C driver for fast
2446 mode (400kHZ). This environment variable is used in
2447 initialization code. So, for changes to be effective
2448 it must be saved and board must be reset.
2450 initrd_high - restrict positioning of initrd images:
2451 If this variable is not set, initrd images will be
2452 copied to the highest possible address in RAM; this
2453 is usually what you want since it allows for
2454 maximum initrd size. If for some reason you want to
2455 make sure that the initrd image is loaded below the
2456 CFG_BOOTMAPSZ limit, you can set this environment
2457 variable to a value of "no" or "off" or "0".
2458 Alternatively, you can set it to a maximum upper
2459 address to use (U-Boot will still check that it
2460 does not overwrite the U-Boot stack and data).
2462 For instance, when you have a system with 16 MB
2463 RAM, and want to reserve 4 MB from use by Linux,
2464 you can do this by adding "mem=12M" to the value of
2465 the "bootargs" variable. However, now you must make
2466 sure that the initrd image is placed in the first
2467 12 MB as well - this can be done with
2469 setenv initrd_high 00c00000
2471 If you set initrd_high to 0xFFFFFFFF, this is an
2472 indication to U-Boot that all addresses are legal
2473 for the Linux kernel, including addresses in flash
2474 memory. In this case U-Boot will NOT COPY the
2475 ramdisk at all. This may be useful to reduce the
2476 boot time on your system, but requires that this
2477 feature is supported by your Linux kernel.
2479 ipaddr - IP address; needed for tftpboot command
2481 loadaddr - Default load address for commands like "bootp",
2482 "rarpboot", "tftpboot", "loadb" or "diskboot"
2484 loads_echo - see CONFIG_LOADS_ECHO
2486 serverip - TFTP server IP address; needed for tftpboot command
2488 bootretry - see CONFIG_BOOT_RETRY_TIME
2490 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2492 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2494 ethprime - When CONFIG_NET_MULTI is enabled controls which
2495 interface is used first.
2497 ethact - When CONFIG_NET_MULTI is enabled controls which
2498 interface is currently active. For example you
2499 can do the following
2501 => setenv ethact FEC ETHERNET
2502 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2503 => setenv ethact SCC ETHERNET
2504 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2506 netretry - When set to "no" each network operation will
2507 either succeed or fail without retrying.
2508 When set to "once" the network operation will
2509 fail when all the available network interfaces
2510 are tried once without success.
2511 Useful on scripts which control the retry operation
2514 tftpsrcport - If this is set, the value is used for TFTP's
2517 tftpdstport - If this is set, the value is used for TFTP's UDP
2518 destination port instead of the Well Know Port 69.
2520 vlan - When set to a value < 4095 the traffic over
2521 ethernet is encapsulated/received over 802.1q
2524 The following environment variables may be used and automatically
2525 updated by the network boot commands ("bootp" and "rarpboot"),
2526 depending the information provided by your boot server:
2528 bootfile - see above
2529 dnsip - IP address of your Domain Name Server
2530 dnsip2 - IP address of your secondary Domain Name Server
2531 gatewayip - IP address of the Gateway (Router) to use
2532 hostname - Target hostname
2534 netmask - Subnet Mask
2535 rootpath - Pathname of the root filesystem on the NFS server
2536 serverip - see above
2539 There are two special Environment Variables:
2541 serial# - contains hardware identification information such
2542 as type string and/or serial number
2543 ethaddr - Ethernet address
2545 These variables can be set only once (usually during manufacturing of
2546 the board). U-Boot refuses to delete or overwrite these variables
2547 once they have been set once.
2550 Further special Environment Variables:
2552 ver - Contains the U-Boot version string as printed
2553 with the "version" command. This variable is
2554 readonly (see CONFIG_VERSION_VARIABLE).
2557 Please note that changes to some configuration parameters may take
2558 only effect after the next boot (yes, that's just like Windoze :-).
2561 Command Line Parsing:
2562 =====================
2564 There are two different command line parsers available with U-Boot:
2565 the old "simple" one, and the much more powerful "hush" shell:
2567 Old, simple command line parser:
2568 --------------------------------
2570 - supports environment variables (through setenv / saveenv commands)
2571 - several commands on one line, separated by ';'
2572 - variable substitution using "... ${name} ..." syntax
2573 - special characters ('$', ';') can be escaped by prefixing with '\',
2575 setenv bootcmd bootm \${address}
2576 - You can also escape text by enclosing in single apostrophes, for example:
2577 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2582 - similar to Bourne shell, with control structures like
2583 if...then...else...fi, for...do...done; while...do...done,
2584 until...do...done, ...
2585 - supports environment ("global") variables (through setenv / saveenv
2586 commands) and local shell variables (through standard shell syntax
2587 "name=value"); only environment variables can be used with "run"
2593 (1) If a command line (or an environment variable executed by a "run"
2594 command) contains several commands separated by semicolon, and
2595 one of these commands fails, then the remaining commands will be
2598 (2) If you execute several variables with one call to run (i. e.
2599 calling run with a list af variables as arguments), any failing
2600 command will cause "run" to terminate, i. e. the remaining
2601 variables are not executed.
2603 Note for Redundant Ethernet Interfaces:
2604 =======================================
2606 Some boards come with redundant ethernet interfaces; U-Boot supports
2607 such configurations and is capable of automatic selection of a
2608 "working" interface when needed. MAC assignment works as follows:
2610 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2611 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2612 "eth1addr" (=>eth1), "eth2addr", ...
2614 If the network interface stores some valid MAC address (for instance
2615 in SROM), this is used as default address if there is NO correspon-
2616 ding setting in the environment; if the corresponding environment
2617 variable is set, this overrides the settings in the card; that means:
2619 o If the SROM has a valid MAC address, and there is no address in the
2620 environment, the SROM's address is used.
2622 o If there is no valid address in the SROM, and a definition in the
2623 environment exists, then the value from the environment variable is
2626 o If both the SROM and the environment contain a MAC address, and
2627 both addresses are the same, this MAC address is used.
2629 o If both the SROM and the environment contain a MAC address, and the
2630 addresses differ, the value from the environment is used and a
2633 o If neither SROM nor the environment contain a MAC address, an error
2640 The "boot" commands of this monitor operate on "image" files which
2641 can be basicly anything, preceeded by a special header; see the
2642 definitions in include/image.h for details; basicly, the header
2643 defines the following image properties:
2645 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2646 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2647 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2648 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2649 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2650 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2651 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2652 * Compression Type (uncompressed, gzip, bzip2)
2658 The header is marked by a special Magic Number, and both the header
2659 and the data portions of the image are secured against corruption by
2666 Although U-Boot should support any OS or standalone application
2667 easily, the main focus has always been on Linux during the design of
2670 U-Boot includes many features that so far have been part of some
2671 special "boot loader" code within the Linux kernel. Also, any
2672 "initrd" images to be used are no longer part of one big Linux image;
2673 instead, kernel and "initrd" are separate images. This implementation
2674 serves several purposes:
2676 - the same features can be used for other OS or standalone
2677 applications (for instance: using compressed images to reduce the
2678 Flash memory footprint)
2680 - it becomes much easier to port new Linux kernel versions because
2681 lots of low-level, hardware dependent stuff are done by U-Boot
2683 - the same Linux kernel image can now be used with different "initrd"
2684 images; of course this also means that different kernel images can
2685 be run with the same "initrd". This makes testing easier (you don't
2686 have to build a new "zImage.initrd" Linux image when you just
2687 change a file in your "initrd"). Also, a field-upgrade of the
2688 software is easier now.
2694 Porting Linux to U-Boot based systems:
2695 ---------------------------------------
2697 U-Boot cannot save you from doing all the necessary modifications to
2698 configure the Linux device drivers for use with your target hardware
2699 (no, we don't intend to provide a full virtual machine interface to
2702 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2704 Just make sure your machine specific header file (for instance
2705 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2706 Information structure as we define in include/u-boot.h, and make
2707 sure that your definition of IMAP_ADDR uses the same value as your
2708 U-Boot configuration in CFG_IMMR.
2711 Configuring the Linux kernel:
2712 -----------------------------
2714 No specific requirements for U-Boot. Make sure you have some root
2715 device (initial ramdisk, NFS) for your target system.
2718 Building a Linux Image:
2719 -----------------------
2721 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2722 not used. If you use recent kernel source, a new build target
2723 "uImage" will exist which automatically builds an image usable by
2724 U-Boot. Most older kernels also have support for a "pImage" target,
2725 which was introduced for our predecessor project PPCBoot and uses a
2726 100% compatible format.
2735 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2736 encapsulate a compressed Linux kernel image with header information,
2737 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2739 * build a standard "vmlinux" kernel image (in ELF binary format):
2741 * convert the kernel into a raw binary image:
2743 ${CROSS_COMPILE}-objcopy -O binary \
2744 -R .note -R .comment \
2745 -S vmlinux linux.bin
2747 * compress the binary image:
2751 * package compressed binary image for U-Boot:
2753 mkimage -A ppc -O linux -T kernel -C gzip \
2754 -a 0 -e 0 -n "Linux Kernel Image" \
2755 -d linux.bin.gz uImage
2758 The "mkimage" tool can also be used to create ramdisk images for use
2759 with U-Boot, either separated from the Linux kernel image, or
2760 combined into one file. "mkimage" encapsulates the images with a 64
2761 byte header containing information about target architecture,
2762 operating system, image type, compression method, entry points, time
2763 stamp, CRC32 checksums, etc.
2765 "mkimage" can be called in two ways: to verify existing images and
2766 print the header information, or to build new images.
2768 In the first form (with "-l" option) mkimage lists the information
2769 contained in the header of an existing U-Boot image; this includes
2770 checksum verification:
2772 tools/mkimage -l image
2773 -l ==> list image header information
2775 The second form (with "-d" option) is used to build a U-Boot image
2776 from a "data file" which is used as image payload:
2778 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2779 -n name -d data_file image
2780 -A ==> set architecture to 'arch'
2781 -O ==> set operating system to 'os'
2782 -T ==> set image type to 'type'
2783 -C ==> set compression type 'comp'
2784 -a ==> set load address to 'addr' (hex)
2785 -e ==> set entry point to 'ep' (hex)
2786 -n ==> set image name to 'name'
2787 -d ==> use image data from 'datafile'
2789 Right now, all Linux kernels for PowerPC systems use the same load
2790 address (0x00000000), but the entry point address depends on the
2793 - 2.2.x kernels have the entry point at 0x0000000C,
2794 - 2.3.x and later kernels have the entry point at 0x00000000.
2796 So a typical call to build a U-Boot image would read:
2798 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2799 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2800 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2801 > examples/uImage.TQM850L
2802 Image Name: 2.4.4 kernel for TQM850L
2803 Created: Wed Jul 19 02:34:59 2000
2804 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2805 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2806 Load Address: 0x00000000
2807 Entry Point: 0x00000000
2809 To verify the contents of the image (or check for corruption):
2811 -> tools/mkimage -l examples/uImage.TQM850L
2812 Image Name: 2.4.4 kernel for TQM850L
2813 Created: Wed Jul 19 02:34:59 2000
2814 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2815 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2816 Load Address: 0x00000000
2817 Entry Point: 0x00000000
2819 NOTE: for embedded systems where boot time is critical you can trade
2820 speed for memory and install an UNCOMPRESSED image instead: this
2821 needs more space in Flash, but boots much faster since it does not
2822 need to be uncompressed:
2824 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2825 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2826 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2827 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2828 > examples/uImage.TQM850L-uncompressed
2829 Image Name: 2.4.4 kernel for TQM850L
2830 Created: Wed Jul 19 02:34:59 2000
2831 Image Type: PowerPC Linux Kernel Image (uncompressed)
2832 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2833 Load Address: 0x00000000
2834 Entry Point: 0x00000000
2837 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2838 when your kernel is intended to use an initial ramdisk:
2840 -> tools/mkimage -n 'Simple Ramdisk Image' \
2841 > -A ppc -O linux -T ramdisk -C gzip \
2842 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2843 Image Name: Simple Ramdisk Image
2844 Created: Wed Jan 12 14:01:50 2000
2845 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2846 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2847 Load Address: 0x00000000
2848 Entry Point: 0x00000000
2851 Installing a Linux Image:
2852 -------------------------
2854 To downloading a U-Boot image over the serial (console) interface,
2855 you must convert the image to S-Record format:
2857 objcopy -I binary -O srec examples/image examples/image.srec
2859 The 'objcopy' does not understand the information in the U-Boot
2860 image header, so the resulting S-Record file will be relative to
2861 address 0x00000000. To load it to a given address, you need to
2862 specify the target address as 'offset' parameter with the 'loads'
2865 Example: install the image to address 0x40100000 (which on the
2866 TQM8xxL is in the first Flash bank):
2868 => erase 40100000 401FFFFF
2874 ## Ready for S-Record download ...
2875 ~>examples/image.srec
2876 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2878 15989 15990 15991 15992
2879 [file transfer complete]
2881 ## Start Addr = 0x00000000
2884 You can check the success of the download using the 'iminfo' command;
2885 this includes a checksum verification so you can be sure no data
2886 corruption happened:
2890 ## Checking Image at 40100000 ...
2891 Image Name: 2.2.13 for initrd on TQM850L
2892 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2893 Data Size: 335725 Bytes = 327 kB = 0 MB
2894 Load Address: 00000000
2895 Entry Point: 0000000c
2896 Verifying Checksum ... OK
2902 The "bootm" command is used to boot an application that is stored in
2903 memory (RAM or Flash). In case of a Linux kernel image, the contents
2904 of the "bootargs" environment variable is passed to the kernel as
2905 parameters. You can check and modify this variable using the
2906 "printenv" and "setenv" commands:
2909 => printenv bootargs
2910 bootargs=root=/dev/ram
2912 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2914 => printenv bootargs
2915 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2918 ## Booting Linux kernel at 40020000 ...
2919 Image Name: 2.2.13 for NFS on TQM850L
2920 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2921 Data Size: 381681 Bytes = 372 kB = 0 MB
2922 Load Address: 00000000
2923 Entry Point: 0000000c
2924 Verifying Checksum ... OK
2925 Uncompressing Kernel Image ... OK
2926 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
2927 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2928 time_init: decrementer frequency = 187500000/60
2929 Calibrating delay loop... 49.77 BogoMIPS
2930 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2933 If you want to boot a Linux kernel with initial ram disk, you pass
2934 the memory addresses of both the kernel and the initrd image (PPBCOOT
2935 format!) to the "bootm" command:
2937 => imi 40100000 40200000
2939 ## Checking Image at 40100000 ...
2940 Image Name: 2.2.13 for initrd on TQM850L
2941 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2942 Data Size: 335725 Bytes = 327 kB = 0 MB
2943 Load Address: 00000000
2944 Entry Point: 0000000c
2945 Verifying Checksum ... OK
2947 ## Checking Image at 40200000 ...
2948 Image Name: Simple Ramdisk Image
2949 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2950 Data Size: 566530 Bytes = 553 kB = 0 MB
2951 Load Address: 00000000
2952 Entry Point: 00000000
2953 Verifying Checksum ... OK
2955 => bootm 40100000 40200000
2956 ## Booting Linux kernel at 40100000 ...
2957 Image Name: 2.2.13 for initrd on TQM850L
2958 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2959 Data Size: 335725 Bytes = 327 kB = 0 MB
2960 Load Address: 00000000
2961 Entry Point: 0000000c
2962 Verifying Checksum ... OK
2963 Uncompressing Kernel Image ... OK
2964 ## Loading RAMDisk Image at 40200000 ...
2965 Image Name: Simple Ramdisk Image
2966 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2967 Data Size: 566530 Bytes = 553 kB = 0 MB
2968 Load Address: 00000000
2969 Entry Point: 00000000
2970 Verifying Checksum ... OK
2971 Loading Ramdisk ... OK
2972 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
2973 Boot arguments: root=/dev/ram
2974 time_init: decrementer frequency = 187500000/60
2975 Calibrating delay loop... 49.77 BogoMIPS
2977 RAMDISK: Compressed image found at block 0
2978 VFS: Mounted root (ext2 filesystem).
2982 More About U-Boot Image Types:
2983 ------------------------------
2985 U-Boot supports the following image types:
2987 "Standalone Programs" are directly runnable in the environment
2988 provided by U-Boot; it is expected that (if they behave
2989 well) you can continue to work in U-Boot after return from
2990 the Standalone Program.
2991 "OS Kernel Images" are usually images of some Embedded OS which
2992 will take over control completely. Usually these programs
2993 will install their own set of exception handlers, device
2994 drivers, set up the MMU, etc. - this means, that you cannot
2995 expect to re-enter U-Boot except by resetting the CPU.
2996 "RAMDisk Images" are more or less just data blocks, and their
2997 parameters (address, size) are passed to an OS kernel that is
2999 "Multi-File Images" contain several images, typically an OS
3000 (Linux) kernel image and one or more data images like
3001 RAMDisks. This construct is useful for instance when you want
3002 to boot over the network using BOOTP etc., where the boot
3003 server provides just a single image file, but you want to get
3004 for instance an OS kernel and a RAMDisk image.
3006 "Multi-File Images" start with a list of image sizes, each
3007 image size (in bytes) specified by an "uint32_t" in network
3008 byte order. This list is terminated by an "(uint32_t)0".
3009 Immediately after the terminating 0 follow the images, one by
3010 one, all aligned on "uint32_t" boundaries (size rounded up to
3011 a multiple of 4 bytes).
3013 "Firmware Images" are binary images containing firmware (like
3014 U-Boot or FPGA images) which usually will be programmed to
3017 "Script files" are command sequences that will be executed by
3018 U-Boot's command interpreter; this feature is especially
3019 useful when you configure U-Boot to use a real shell (hush)
3020 as command interpreter.
3026 One of the features of U-Boot is that you can dynamically load and
3027 run "standalone" applications, which can use some resources of
3028 U-Boot like console I/O functions or interrupt services.
3030 Two simple examples are included with the sources:
3035 'examples/hello_world.c' contains a small "Hello World" Demo
3036 application; it is automatically compiled when you build U-Boot.
3037 It's configured to run at address 0x00040004, so you can play with it
3041 ## Ready for S-Record download ...
3042 ~>examples/hello_world.srec
3043 1 2 3 4 5 6 7 8 9 10 11 ...
3044 [file transfer complete]
3046 ## Start Addr = 0x00040004
3048 => go 40004 Hello World! This is a test.
3049 ## Starting application at 0x00040004 ...
3060 Hit any key to exit ...
3062 ## Application terminated, rc = 0x0
3064 Another example, which demonstrates how to register a CPM interrupt
3065 handler with the U-Boot code, can be found in 'examples/timer.c'.
3066 Here, a CPM timer is set up to generate an interrupt every second.
3067 The interrupt service routine is trivial, just printing a '.'
3068 character, but this is just a demo program. The application can be
3069 controlled by the following keys:
3071 ? - print current values og the CPM Timer registers
3072 b - enable interrupts and start timer
3073 e - stop timer and disable interrupts
3074 q - quit application
3077 ## Ready for S-Record download ...
3078 ~>examples/timer.srec
3079 1 2 3 4 5 6 7 8 9 10 11 ...
3080 [file transfer complete]
3082 ## Start Addr = 0x00040004
3085 ## Starting application at 0x00040004 ...
3088 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3091 [q, b, e, ?] Set interval 1000000 us
3094 [q, b, e, ?] ........
3095 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3098 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3101 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3104 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3106 [q, b, e, ?] ...Stopping timer
3108 [q, b, e, ?] ## Application terminated, rc = 0x0
3114 Over time, many people have reported problems when trying to use the
3115 "minicom" terminal emulation program for serial download. I (wd)
3116 consider minicom to be broken, and recommend not to use it. Under
3117 Unix, I recommend to use C-Kermit for general purpose use (and
3118 especially for kermit binary protocol download ("loadb" command), and
3119 use "cu" for S-Record download ("loads" command).
3121 Nevertheless, if you absolutely want to use it try adding this
3122 configuration to your "File transfer protocols" section:
3124 Name Program Name U/D FullScr IO-Red. Multi
3125 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3126 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3132 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3133 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3135 Building requires a cross environment; it is known to work on
3136 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3137 need gmake since the Makefiles are not compatible with BSD make).
3138 Note that the cross-powerpc package does not install include files;
3139 attempting to build U-Boot will fail because <machine/ansi.h> is
3140 missing. This file has to be installed and patched manually:
3142 # cd /usr/pkg/cross/powerpc-netbsd/include
3144 # ln -s powerpc machine
3145 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3146 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3148 Native builds *don't* work due to incompatibilities between native
3149 and U-Boot include files.
3151 Booting assumes that (the first part of) the image booted is a
3152 stage-2 loader which in turn loads and then invokes the kernel
3153 proper. Loader sources will eventually appear in the NetBSD source
3154 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3155 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3158 Implementation Internals:
3159 =========================
3161 The following is not intended to be a complete description of every
3162 implementation detail. However, it should help to understand the
3163 inner workings of U-Boot and make it easier to port it to custom
3167 Initial Stack, Global Data:
3168 ---------------------------
3170 The implementation of U-Boot is complicated by the fact that U-Boot
3171 starts running out of ROM (flash memory), usually without access to
3172 system RAM (because the memory controller is not initialized yet).
3173 This means that we don't have writable Data or BSS segments, and BSS
3174 is not initialized as zero. To be able to get a C environment working
3175 at all, we have to allocate at least a minimal stack. Implementation
3176 options for this are defined and restricted by the CPU used: Some CPU
3177 models provide on-chip memory (like the IMMR area on MPC8xx and
3178 MPC826x processors), on others (parts of) the data cache can be
3179 locked as (mis-) used as memory, etc.
3181 Chris Hallinan posted a good summary of these issues to the
3182 u-boot-users mailing list:
3184 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3185 From: "Chris Hallinan" <clh@net1plus.com>
3186 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3189 Correct me if I'm wrong, folks, but the way I understand it
3190 is this: Using DCACHE as initial RAM for Stack, etc, does not
3191 require any physical RAM backing up the cache. The cleverness
3192 is that the cache is being used as a temporary supply of
3193 necessary storage before the SDRAM controller is setup. It's
3194 beyond the scope of this list to expain the details, but you
3195 can see how this works by studying the cache architecture and
3196 operation in the architecture and processor-specific manuals.
3198 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3199 is another option for the system designer to use as an
3200 initial stack/ram area prior to SDRAM being available. Either
3201 option should work for you. Using CS 4 should be fine if your
3202 board designers haven't used it for something that would
3203 cause you grief during the initial boot! It is frequently not
3206 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3207 with your processor/board/system design. The default value
3208 you will find in any recent u-boot distribution in
3209 walnut.h should work for you. I'd set it to a value larger
3210 than your SDRAM module. If you have a 64MB SDRAM module, set
3211 it above 400_0000. Just make sure your board has no resources
3212 that are supposed to respond to that address! That code in
3213 start.S has been around a while and should work as is when
3214 you get the config right.
3219 It is essential to remember this, since it has some impact on the C
3220 code for the initialization procedures:
3222 * Initialized global data (data segment) is read-only. Do not attempt
3225 * Do not use any unitialized global data (or implicitely initialized
3226 as zero data - BSS segment) at all - this is undefined, initiali-
3227 zation is performed later (when relocating to RAM).
3229 * Stack space is very limited. Avoid big data buffers or things like
3232 Having only the stack as writable memory limits means we cannot use
3233 normal global data to share information beween the code. But it
3234 turned out that the implementation of U-Boot can be greatly
3235 simplified by making a global data structure (gd_t) available to all
3236 functions. We could pass a pointer to this data as argument to _all_
3237 functions, but this would bloat the code. Instead we use a feature of
3238 the GCC compiler (Global Register Variables) to share the data: we
3239 place a pointer (gd) to the global data into a register which we
3240 reserve for this purpose.
3242 When choosing a register for such a purpose we are restricted by the
3243 relevant (E)ABI specifications for the current architecture, and by
3244 GCC's implementation.
3246 For PowerPC, the following registers have specific use:
3249 R3-R4: parameter passing and return values
3250 R5-R10: parameter passing
3251 R13: small data area pointer
3255 (U-Boot also uses R14 as internal GOT pointer.)
3257 ==> U-Boot will use R29 to hold a pointer to the global data
3259 Note: on PPC, we could use a static initializer (since the
3260 address of the global data structure is known at compile time),
3261 but it turned out that reserving a register results in somewhat
3262 smaller code - although the code savings are not that big (on
3263 average for all boards 752 bytes for the whole U-Boot image,
3264 624 text + 127 data).
3266 On ARM, the following registers are used:
3268 R0: function argument word/integer result
3269 R1-R3: function argument word
3271 R10: stack limit (used only if stack checking if enabled)
3272 R11: argument (frame) pointer
3273 R12: temporary workspace
3276 R15: program counter
3278 ==> U-Boot will use R8 to hold a pointer to the global data
3284 U-Boot runs in system state and uses physical addresses, i.e. the
3285 MMU is not used either for address mapping nor for memory protection.
3287 The available memory is mapped to fixed addresses using the memory
3288 controller. In this process, a contiguous block is formed for each
3289 memory type (Flash, SDRAM, SRAM), even when it consists of several
3290 physical memory banks.
3292 U-Boot is installed in the first 128 kB of the first Flash bank (on
3293 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3294 booting and sizing and initializing DRAM, the code relocates itself
3295 to the upper end of DRAM. Immediately below the U-Boot code some
3296 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3297 configuration setting]. Below that, a structure with global Board
3298 Info data is placed, followed by the stack (growing downward).
3300 Additionally, some exception handler code is copied to the low 8 kB
3301 of DRAM (0x00000000 ... 0x00001FFF).
3303 So a typical memory configuration with 16 MB of DRAM could look like
3306 0x0000 0000 Exception Vector code
3309 0x0000 2000 Free for Application Use
3315 0x00FB FF20 Monitor Stack (Growing downward)
3316 0x00FB FFAC Board Info Data and permanent copy of global data
3317 0x00FC 0000 Malloc Arena
3320 0x00FE 0000 RAM Copy of Monitor Code
3321 ... eventually: LCD or video framebuffer
3322 ... eventually: pRAM (Protected RAM - unchanged by reset)
3323 0x00FF FFFF [End of RAM]
3326 System Initialization:
3327 ----------------------
3329 In the reset configuration, U-Boot starts at the reset entry point
3330 (on most PowerPC systens at address 0x00000100). Because of the reset
3331 configuration for CS0# this is a mirror of the onboard Flash memory.
3332 To be able to re-map memory U-Boot then jumps to its link address.
3333 To be able to implement the initialization code in C, a (small!)
3334 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3335 which provide such a feature like MPC8xx or MPC8260), or in a locked
3336 part of the data cache. After that, U-Boot initializes the CPU core,
3337 the caches and the SIU.
3339 Next, all (potentially) available memory banks are mapped using a
3340 preliminary mapping. For example, we put them on 512 MB boundaries
3341 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3342 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3343 programmed for SDRAM access. Using the temporary configuration, a
3344 simple memory test is run that determines the size of the SDRAM
3347 When there is more than one SDRAM bank, and the banks are of
3348 different size, the largest is mapped first. For equal size, the first
3349 bank (CS2#) is mapped first. The first mapping is always for address
3350 0x00000000, with any additional banks following immediately to create
3351 contiguous memory starting from 0.
3353 Then, the monitor installs itself at the upper end of the SDRAM area
3354 and allocates memory for use by malloc() and for the global Board
3355 Info data; also, the exception vector code is copied to the low RAM
3356 pages, and the final stack is set up.
3358 Only after this relocation will you have a "normal" C environment;
3359 until that you are restricted in several ways, mostly because you are
3360 running from ROM, and because the code will have to be relocated to a
3364 U-Boot Porting Guide:
3365 ----------------------
3367 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3371 int main (int argc, char *argv[])
3373 sighandler_t no_more_time;
3375 signal (SIGALRM, no_more_time);
3376 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3378 if (available_money > available_manpower) {
3379 pay consultant to port U-Boot;
3383 Download latest U-Boot source;
3385 Subscribe to u-boot-users mailing list;
3388 email ("Hi, I am new to U-Boot, how do I get started?");
3392 Read the README file in the top level directory;
3393 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3394 Read the source, Luke;
3397 if (available_money > toLocalCurrency ($2500)) {
3400 Add a lot of aggravation and time;
3403 Create your own board support subdirectory;
3405 Create your own board config file;
3409 Add / modify source code;
3413 email ("Hi, I am having problems...");
3415 Send patch file to Wolfgang;
3420 void no_more_time (int sig)
3429 All contributions to U-Boot should conform to the Linux kernel
3430 coding style; see the file "Documentation/CodingStyle" in your Linux
3431 kernel source directory.
3433 Please note that U-Boot is implemented in C (and to some small parts
3434 in Assembler); no C++ is used, so please do not use C++ style
3435 comments (//) in your code.
3437 Please also stick to the following formatting rules:
3438 - remove any trailing white space
3439 - use TAB characters for indentation, not spaces
3440 - make sure NOT to use DOS '\r\n' line feeds
3441 - do not add more than 2 empty lines to source files
3442 - do not add trailing empty lines to source files
3444 Submissions which do not conform to the standards may be returned
3445 with a request to reformat the changes.
3451 Since the number of patches for U-Boot is growing, we need to
3452 establish some rules. Submissions which do not conform to these rules
3453 may be rejected, even when they contain important and valuable stuff.
3455 Patches shall be sent to the u-boot-users mailing list.
3457 When you send a patch, please include the following information with
3460 * For bug fixes: a description of the bug and how your patch fixes
3461 this bug. Please try to include a way of demonstrating that the
3462 patch actually fixes something.
3464 * For new features: a description of the feature and your
3467 * A CHANGELOG entry as plaintext (separate from the patch)
3469 * For major contributions, your entry to the CREDITS file
3471 * When you add support for a new board, don't forget to add this
3472 board to the MAKEALL script, too.
3474 * If your patch adds new configuration options, don't forget to
3475 document these in the README file.
3477 * The patch itself. If you are accessing the CVS repository use "cvs
3478 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3479 version of diff does not support these options, then get the latest
3480 version of GNU diff.
3482 The current directory when running this command shall be the top
3483 level directory of the U-Boot source tree, or it's parent directory
3484 (i. e. please make sure that your patch includes sufficient
3485 directory information for the affected files).
3487 We accept patches as plain text, MIME attachments or as uuencoded
3490 * If one logical set of modifications affects or creates several
3491 files, all these changes shall be submitted in a SINGLE patch file.
3493 * Changesets that contain different, unrelated modifications shall be
3494 submitted as SEPARATE patches, one patch per changeset.
3499 * Before sending the patch, run the MAKEALL script on your patched
3500 source tree and make sure that no errors or warnings are reported
3501 for any of the boards.
3503 * Keep your modifications to the necessary minimum: A patch
3504 containing several unrelated changes or arbitrary reformats will be
3505 returned with a request to re-formatting / split it.
3507 * If you modify existing code, make sure that your new code does not
3508 add to the memory footprint of the code ;-) Small is beautiful!
3509 When adding new features, these should compile conditionally only
3510 (using #ifdef), and the resulting code with the new feature
3511 disabled must not need more memory than the old code without your
3514 * Remember that there is a size limit of 40 kB per message on the
3515 u-boot-users mailing list. Compression may help.