2 # (C) Copyright 2000 - 2002
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependend files
123 - common Misc architecture independend functions
124 - cpu CPU specific files
125 - disk Code for disk drive partition handling
126 - doc Documentation (don't expect too much)
127 - drivers Common used device drivers
128 - dtt Digital Thermometer and Thermostat drivers
129 - examples Example code for standalone applications, etc.
130 - include Header Files
131 - disk Harddisk interface code
132 - net Networking code
133 - ppc Files generic to PowerPC architecture
134 - post Power On Self Test
135 - post/arch Symlink to architecture specific Power On Self Test
136 - post/arch-ppc PowerPC architecture specific Power On Self Test
137 - post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
138 - post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
139 - rtc Real Time Clock drivers
140 - tools Tools to build S-Record or U-Boot images, etc.
142 - cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
143 - cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
144 - cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
145 - cpu/mpc824x Files specific to Motorola MPC824x CPUs
146 - cpu/mpc8260 Files specific to Motorola MPC8260 CPU
147 - cpu/ppc4xx Files specific to IBM 4xx CPUs
149 - board/LEOX/ Files specific to boards manufactured by The LEOX team
150 - board/LEOX/elpt860 Files specific to ELPT860 boards
152 Files specific to RPXClassic boards
153 - board/RPXlite Files specific to RPXlite boards
154 - board/c2mon Files specific to c2mon boards
155 - board/cmi Files specific to cmi boards
156 - board/cogent Files specific to Cogent boards
157 (need further configuration)
158 Files specific to CPCIISER4 boards
159 - board/cpu86 Files specific to CPU86 boards
160 - board/cray/ Files specific to boards manufactured by Cray
161 - board/cray/L1 Files specific to L1 boards
162 - board/cu824 Files specific to CU824 boards
163 - board/ebony Files specific to IBM Ebony board
164 - board/eric Files specific to ERIC boards
165 - board/esd/ Files specific to boards manufactured by ESD
166 - board/esd/adciop Files specific to ADCIOP boards
167 - board/esd/ar405 Files specific to AR405 boards
168 - board/esd/canbt Files specific to CANBT boards
169 - board/esd/cpci405 Files specific to CPCI405 boards
170 - board/esd/cpciiser4 Files specific to CPCIISER4 boards
171 - board/esd/common Common files for ESD boards
172 - board/esd/dasa_sim Files specific to DASA_SIM boards
173 - board/esd/du405 Files specific to DU405 boards
174 - board/esd/ocrtc Files specific to OCRTC boards
175 - board/esd/pci405 Files specific to PCI405 boards
177 Files specific to ESTEEM192E boards
178 - board/etx094 Files specific to ETX_094 boards
180 Files specific to EVB64260 boards
181 - board/fads Files specific to FADS boards
182 - board/flagadm Files specific to FLAGADM boards
183 - board/gen860t Files specific to GEN860T boards
184 - board/genietv Files specific to GENIETV boards
185 - board/gth Files specific to GTH boards
186 - board/hermes Files specific to HERMES boards
187 - board/hymod Files specific to HYMOD boards
188 - board/icu862 Files specific to ICU862 boards
189 - board/ip860 Files specific to IP860 boards
191 Files specific to Interphase4539 boards
192 - board/ivm Files specific to IVMS8/IVML24 boards
193 - board/lantec Files specific to LANTEC boards
194 - board/lwmon Files specific to LWMON boards
195 - board/mbx8xx Files specific to MBX boards
197 Files specific to MMPC8260ADS boards
198 - board/mpl/ Files specific to boards manufactured by MPL
199 - board/mpl/common Common files for MPL boards
200 - board/mpl/pip405 Files specific to PIP405 boards
201 - board/mpl/mip405 Files specific to MIP405 boards
202 - board/musenki Files specific to MUSEKNI boards
203 - board/mvs1 Files specific to MVS1 boards
204 - board/nx823 Files specific to NX823 boards
205 - board/oxc Files specific to OXC boards
206 - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
207 - board/pm826 Files specific to PM826 boards
209 Files specific to PPMC8260 boards
211 Files specific to RPXsuper boards
213 Files specific to RSDproto boards
215 Files specific to Sandpoint boards
216 - board/sbc8260 Files specific to SBC8260 boards
217 - board/sacsng Files specific to SACSng boards
218 - board/siemens Files specific to boards manufactured by Siemens AG
219 - board/siemens/CCM Files specific to CCM boards
220 - board/siemens/IAD210 Files specific to IAD210 boards
221 - board/siemens/SCM Files specific to SCM boards
222 - board/siemens/pcu_e Files specific to PCU_E boards
223 - board/sixnet Files specific to SIXNET boards
224 - board/spd8xx Files specific to SPD8xxTS boards
225 - board/tqm8260 Files specific to TQM8260 boards
226 - board/tqm8xx Files specific to TQM8xxL boards
227 - board/w7o Files specific to W7O boards
229 Files specific to Walnut405 boards
230 - board/westel/ Files specific to boards manufactured by Westel Wireless
231 - board/westel/amx860 Files specific to AMX860 boards
232 - board/utx8245 Files specific to UTX8245 boards
234 Software Configuration:
235 =======================
237 Configuration is usually done using C preprocessor defines; the
238 rationale behind that is to avoid dead code whenever possible.
240 There are two classes of configuration variables:
242 * Configuration _OPTIONS_:
243 These are selectable by the user and have names beginning with
246 * Configuration _SETTINGS_:
247 These depend on the hardware etc. and should not be meddled with if
248 you don't know what you're doing; they have names beginning with
251 Later we will add a configuration tool - probably similar to or even
252 identical to what's used for the Linux kernel. Right now, we have to
253 do the configuration by hand, which means creating some symbolic
254 links and editing some configuration files. We use the TQM8xxL boards
258 Selection of Processor Architecture and Board Type:
259 ---------------------------------------------------
261 For all supported boards there are ready-to-use default
262 configurations available; just type "make <board_name>_config".
264 Example: For a TQM823L module type:
269 For the Cogent platform, you need to specify the cpu type as well;
270 e.g. "make cogent_mpc8xx_config". And also configure the cogent
271 directory according to the instructions in cogent/README.
274 Configuration Options:
275 ----------------------
277 Configuration depends on the combination of board and CPU type; all
278 such information is kept in a configuration file
279 "include/configs/<board_name>.h".
281 Example: For a TQM823L module, all configuration settings are in
282 "include/configs/TQM823L.h".
285 Many of the options are named exactly as the corresponding Linux
286 kernel configuration options. The intention is to make it easier to
287 build a config tool - later.
290 The following options need to be configured:
292 - CPU Type: Define exactly one of
296 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
298 or CONFIG_MPC824X, CONFIG_MPC8260
311 - Board Type: Define exactly one of
313 PowerPC based boards:
314 ---------------------
316 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
317 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
318 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
319 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
320 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
321 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
322 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
323 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
324 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
325 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
326 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
327 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
328 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
329 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
330 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
331 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
332 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
333 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
334 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
335 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
336 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
337 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
338 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
339 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
340 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
341 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
342 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
343 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
344 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
345 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
346 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI
351 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
352 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
353 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
357 - CPU Module Type: (if CONFIG_COGENT is defined)
358 Define exactly one of
360 --- FIXME --- not tested yet:
361 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
362 CONFIG_CMA287_23, CONFIG_CMA287_50
364 - Motherboard Type: (if CONFIG_COGENT is defined)
365 Define exactly one of
366 CONFIG_CMA101, CONFIG_CMA102
368 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
369 Define one or more of
372 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
373 Define one or more of
374 CONFIG_LCD_HEARTBEAT - update a character position on
375 the lcd display every second with
378 - MPC824X Family Member (if CONFIG_MPC824X is defined)
379 Define exactly one of
380 CONFIG_MPC8240, CONFIG_MPC8245
382 - 8xx CPU Options: (if using an 8xx cpu)
383 Define one or more of
384 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g.
385 no 32KHz reference PIT/RTC clock
390 U-Boot stores all clock information in Hz
391 internally. For binary compatibility with older Linux
392 kernels (which expect the clocks passed in the
393 bd_info data to be in MHz) the environment variable
394 "clocks_in_mhz" can be defined so that U-Boot
395 converts clock data to MHZ before passing it to the
398 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
399 "clocks_in_mhz=1" is automatically included in the
403 Depending on board, define exactly one serial port
404 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
405 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
406 console by defining CONFIG_8xx_CONS_NONE
408 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
409 port routines must be defined elsewhere
410 (i.e. serial_init(), serial_getc(), ...)
413 Enables console device for a color framebuffer. Needs following
414 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
415 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
417 VIDEO_HW_RECTFILL graphic chip supports
420 VIDEO_HW_BITBLT graphic chip supports
421 bit-blit (cf. smiLynxEM)
422 VIDEO_VISIBLE_COLS visible pixel columns
424 VIDEO_VISIBLE_ROWS visible pixel rows
425 VIDEO_PIXEL_SIZE bytes per pixel
426 VIDEO_DATA_FORMAT graphic data format
427 (0-5, cf. cfb_console.c)
428 VIDEO_FB_ADRS framebuffer address
429 VIDEO_KBD_INIT_FCT keyboard int fct
430 (i.e. i8042_kbd_init())
431 VIDEO_TSTC_FCT test char fct
433 VIDEO_GETC_FCT get char fct
435 CONFIG_CONSOLE_CURSOR cursor drawing on/off
436 (requires blink timer
438 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
439 CONFIG_CONSOLE_TIME display time/date info in
441 (requires CFG_CMD_DATE)
442 CONFIG_VIDEO_LOGO display Linux logo in
444 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
445 linux_logo.h for logo.
446 Requires CONFIG_VIDEO_LOGO
447 CONFIG_CONSOLE_EXTRA_INFO
448 addional board info beside
451 When CONFIG_CFB_CONSOLE is defined, video console is
452 default i/o. Serial console can be forced with
453 environment 'console=serial'.
456 CONFIG_BAUDRATE - in bps
457 Select one of the baudrates listed in
458 CFG_BAUDRATE_TABLE, see below.
460 - Interrupt driven serial port input:
461 CONFIG_SERIAL_SOFTWARE_FIFO
464 Use an interrupt handler for receiving data on the
465 serial port. It also enables using hardware handshake
466 (RTS/CTS) and UART's built-in FIFO. Set the number of
467 bytes the interrupt driven input buffer should have.
469 Set to 0 to disable this feature (this is the default).
470 This will also disable hardware handshake.
472 - Boot Delay: CONFIG_BOOTDELAY - in seconds
473 Delay before automatically booting the default image;
474 set to -1 to disable autoboot.
476 See doc/README.autoboot for these options that
477 work with CONFIG_BOOTDELAY. None are required.
478 CONFIG_BOOT_RETRY_TIME
479 CONFIG_BOOT_RETRY_MIN
480 CONFIG_AUTOBOOT_KEYED
481 CONFIG_AUTOBOOT_PROMPT
482 CONFIG_AUTOBOOT_DELAY_STR
483 CONFIG_AUTOBOOT_STOP_STR
484 CONFIG_AUTOBOOT_DELAY_STR2
485 CONFIG_AUTOBOOT_STOP_STR2
486 CONFIG_ZERO_BOOTDELAY_CHECK
487 CONFIG_RESET_TO_RETRY
491 Only needed when CONFIG_BOOTDELAY is enabled;
492 define a command string that is automatically executed
493 when no character is read on the console interface
494 within "Boot Delay" after reset.
497 This can be used to pass arguments to the bootm
498 command. The value of CONFIG_BOOTARGS goes into the
499 environment value "bootargs".
501 CONFIG_RAMBOOT and CONFIG_NFSBOOT
502 The value of these goes into the environment as
503 "ramboot" and "nfsboot" respectively, and can be used
504 as a convenience, when switching between booting from
510 When this option is #defined, the existence of the
511 environment variable "preboot" will be checked
512 immediately before starting the CONFIG_BOOTDELAY
513 countdown and/or running the auto-boot command resp.
514 entering interactive mode.
516 This feature is especially useful when "preboot" is
517 automatically generated or modified. For an example
518 see the LWMON board specific code: here "preboot" is
519 modified when the user holds down a certain
520 combination of keys on the (special) keyboard when
523 - Serial Download Echo Mode:
525 If defined to 1, all characters received during a
526 serial download (using the "loads" command) are
527 echoed back. This might be needed by some terminal
528 emulations (like "cu"), but may as well just take
529 time on others. This setting #define's the initial
530 value of the "loads_echo" environment variable.
532 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
534 Select one of the baudrates listed in
535 CFG_BAUDRATE_TABLE, see below.
539 Most monitor functions can be selected (or
540 de-selected) by adjusting the definition of
541 CONFIG_COMMANDS; to select individual functions,
542 #define CONFIG_COMMANDS by "OR"ing any of the
545 #define enables commands:
546 -------------------------
547 CFG_CMD_ASKENV * ask for env variable
549 CFG_CMD_BEDBUG Include BedBug Debugger
551 CFG_CMD_CACHE icache, dcache
552 CFG_CMD_CONSOLE coninfo
553 CFG_CMD_DATE * support for RTC, date/time...
554 CFG_CMD_DHCP DHCP support
555 CFG_CMD_ECHO * echo arguments
556 CFG_CMD_EEPROM * EEPROM read/write support
557 CFG_CMD_ELF bootelf, bootvx
559 CFG_CMD_FDC * Floppy Disk Support
560 CFG_CMD_FDOS * Dos diskette Support
561 CFG_CMD_FLASH flinfo, erase, protect
562 CFG_CMD_FPGA FPGA device initialization support
563 CFG_CMD_I2C * I2C serial bus support
564 CFG_CMD_IDE * IDE harddisk support
566 CFG_CMD_IMMAP * IMMR dump support
567 CFG_CMD_IRQ * irqinfo
571 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
573 CFG_CMD_MII MII utility commands
574 CFG_CMD_NET bootp, tftpboot, rarpboot
575 CFG_CMD_PCI * pciinfo
576 CFG_CMD_PCMCIA * PCMCIA support
577 CFG_CMD_REGINFO * Register dump
578 CFG_CMD_RUN run command in env variable
579 CFG_CMD_SCSI * SCSI Support
580 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
581 CFG_CMD_SPI * SPI serial bus support
582 CFG_CMD_USB * USB support
583 CFG_CMD_BSP * Board SPecific functions
584 -----------------------------------------------
587 CFG_CMD_DFL Default configuration; at the moment
588 this is includes all commands, except
589 the ones marked with "*" in the list
592 If you don't define CONFIG_COMMANDS it defaults to
593 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
594 override the default settings in the respective
597 EXAMPLE: If you want all functions except of network
598 support you can write:
600 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
603 Note: Don't enable the "icache" and "dcache" commands
604 (configuration option CFG_CMD_CACHE) unless you know
605 what you (and your U-Boot users) are doing. Data
606 cache cannot be enabled on systems like the 8xx or
607 8260 (where accesses to the IMMR region must be
608 uncached), and it cannot be disabled on all other
609 systems where we (mis-) use the data cache to hold an
610 initial stack and some data.
613 XXX - this list needs to get updated!
617 If this variable is defined, it enables watchdog
618 support. There must support in the platform specific
619 code for a watchdog. For the 8xx and 8260 CPUs, the
620 SIU Watchdog feature is enabled in the SYPCR
625 When CFG_CMD_DATE is selected, the type of the RTC
626 has to be selected, too. Define exactly one of the
629 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
630 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
631 CONFIG_RTC_MC146818 - use MC146818 RTC
632 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
633 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
634 CONFIG_RTC_DS164x - use Dallas DS164x RTC
638 When CONFIG_TIMESTAMP is selected, the timestamp
639 (date and time) of an image is printed by image
640 commands like bootm or iminfo. This option is
641 automatically enabled when you select CFG_CMD_DATE .
644 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
645 and/or CONFIG_ISO_PARTITION
647 If IDE or SCSI support is enabled (CFG_CMD_IDE or
648 CFG_CMD_SCSI) you must configure support for at least
649 one partition type as well.
652 CONFIG_IDE_RESET_ROUTINE
654 Set this to define that instead of a reset Pin, the
655 routine ide_set_reset(int idereset) will be used.
660 Set this to enable ATAPI support.
663 At the moment only there is only support for the
664 SYM53C8XX SCSI controller; define
665 CONFIG_SCSI_SYM53C8XX to enable it.
667 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
668 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
669 CFG_SCSI_MAX_LUN] can be adjusted to define the
670 maximum numbers of LUNs, SCSI ID's and target
672 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
674 - NETWORK Support (PCI):
676 Support for Intel 82557/82559/82559ER chips.
677 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
678 write routine for first time initialisation.
681 Support for Digital 2114x chips.
682 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
683 modem chip initialisation (KS8761/QS6611).
686 Support for National dp83815 chips.
689 Support for National dp8382[01] gigabit chips.
692 At the moment only the UHCI host controller is
693 supported (PIP405, MIP405); define
694 CONFIG_USB_UHCI to enable it.
695 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
696 end define CONFIG_USB_STORAGE to enable the USB
699 Supported are USB Keyboards and USB Floppy drives
705 Define this to enable standard (PC-Style) keyboard
709 Standard PC keyboard driver with US (is default) and
710 GERMAN key layout (switch via environment 'keymap=de') support.
711 Export function i8042_kbd_init, i8042_tstc and i8042_getc
712 for cfb_console. Supports cursor blinking.
717 Define this to enable video support (for output to
722 Enable Chips & Technologies 69000 Video chip
724 CONFIG_VIDEO_SMI_LYNXEM
725 Enable Silicon Motion SMI 712/710/810 Video chip
726 Videomode are selected via environment 'videomode' with
727 standard LiLo mode numbers.
728 Following modes are supported (* is default):
730 800x600 1024x768 1280x1024
731 256 (8bit) 303* 305 307
732 65536 (16bit) 314 317 31a
733 16,7 Mill (24bit) 315 318 31b
734 (i.e. setenv videomode 317; saveenv; reset;)
736 CONFIG_VIDEO_SED13806
737 Enable Epson SED13806 driver. This driver supports 8bpp
738 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
739 or CONFIG_VIDEO_SED13806_16BPP
742 - LCD Support: CONFIG_LCD
744 Define this to enable LCD support (for output to LCD
745 display); also select one of the supported displays
746 by defining one of these:
748 CONFIG_NEC_NL6648AC33:
750 NEC NL6648AC33-18. Active, color, single scan.
752 CONFIG_NEC_NL6648BC20
754 NEC NL6648BC20-08. 6.5", 640x480.
755 Active, color, single scan.
759 Sharp 320x240. Active, color, single scan.
760 It isn't 16x9, and I am not sure what it is.
762 CONFIG_SHARP_LQ64D341
764 Sharp LQ64D341 display, 640x480.
765 Active, color, single scan.
769 HLD1045 display, 640x480.
770 Active, color, single scan.
774 Optrex CBL50840-2 NF-FW 99 22 M5
776 Hitachi LMG6912RPFC-00T
780 320x240. Black & white.
782 Normally display is black on white background; define
783 CFG_WHITE_ON_BLACK to get it inverted.
790 Define a default value for ethernet address to use
791 for the respective ethernet interface, in case this
792 is not determined automatically.
797 Define a default value for the IP address to use for
798 the default ethernet interface, in case this is not
799 determined through e.g. bootp.
804 Defines a default value for theIP address of a TFTP
805 server to contact when using the "tftboot" command.
807 - BOOTP Recovery Mode:
808 CONFIG_BOOTP_RANDOM_DELAY
810 If you have many targets in a network that try to
811 boot using BOOTP, you may want to avoid that all
812 systems send out BOOTP requests at precisely the same
813 moment (which would happen for instance at recovery
814 from a power failure, when all systems will try to
815 boot, thus flooding the BOOTP server. Defining
816 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
817 inserted before sending out BOOTP requests. The
818 following delays are insterted then:
820 1st BOOTP request: delay 0 ... 1 sec
821 2nd BOOTP request: delay 0 ... 2 sec
822 3rd BOOTP request: delay 0 ... 4 sec
824 BOOTP requests: delay 0 ... 8 sec
826 - Status LED: CONFIG_STATUS_LED
828 Several configurations allow to display the current
829 status using a LED. For instance, the LED will blink
830 fast while running U-Boot code, stop blinking as
831 soon as a reply to a BOOTP request was received, and
832 start blinking slow once the Linux kernel is running
833 (supported by a status LED driver in the Linux
834 kernel). Defining CONFIG_STATUS_LED enables this
837 - CAN Support: CONFIG_CAN_DRIVER
839 Defining CONFIG_CAN_DRIVER enables CAN driver support
840 on those systems that support this (optional)
841 feature, like the TQM8xxL modules.
843 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
845 Enables I2C serial bus commands. If this is selected,
846 either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must be defined
847 to include the appropriate I2C driver.
849 See also: common/cmd_i2c.c for a description of the
850 command line interface.
855 Selects the CPM hardware driver for I2C.
859 Use software (aka bit-banging) driver instead of CPM
860 or similar hardware support for I2C. This is configured
861 via the following defines.
865 (Optional). Any commands necessary to enable I2C
866 controller or configure ports.
870 (Only for MPC8260 CPU). The I/O port to use (the code
871 assumes both bits are on the same port). Valid values
872 are 0..3 for ports A..D.
876 The code necessary to make the I2C data line active
877 (driven). If the data line is open collector, this
882 The code necessary to make the I2C data line tri-stated
883 (inactive). If the data line is open collector, this
888 Code that returns TRUE if the I2C data line is high,
893 If <bit> is TRUE, sets the I2C data line high. If it
894 is FALSE, it clears it (low).
898 If <bit> is TRUE, sets the I2C clock line high. If it
899 is FALSE, it clears it (low).
903 This delay is invoked four times per clock cycle so this
904 controls the rate of data transfer. The data rate thus
905 is 1 / (I2C_DELAY * 4).
909 When a board is reset during an i2c bus transfer
910 chips might think that the current transfer is still
911 in progress. On some boards it is possible to access
912 the i2c SCLK line directly, either by using the
913 processor pin as a GPIO or by having a second pin
914 connected to the bus. If this option is defined a
915 custom i2c_init_board() routine in boards/xxx/board.c
916 is run early in the boot sequence.
918 - SPI Support: CONFIG_SPI
920 Enables SPI driver (so far only tested with
921 SPI EEPROM, also an instance works with Crystal A/D and
922 D/As on the SACSng board)
926 Enables extended (16-bit) SPI EEPROM addressing.
927 (symmetrical to CONFIG_I2C_X)
931 Enables a software (bit-bang) SPI driver rather than
932 using hardware support. This is a general purpose
933 driver that only requires three general I/O port pins
934 (two outputs, one input) to function. If this is
935 defined, the board configuration must define several
936 SPI configuration items (port pins to use, etc). For
937 an example, see include/configs/sacsng.h.
939 - FPGA Support: CONFIG_FPGA_COUNT
941 Specify the number of FPGA devices to support.
945 Used to specify the types of FPGA devices. For
947 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
949 CFG_FPGA_PROG_FEEDBACK
951 Enable printing of hash marks during FPGA
956 Enable checks on FPGA configuration interface busy
957 status by the configuration function. This option
958 will require a board or device specific function to
963 If defined, a function that provides delays in the
964 FPGA configuration driver.
968 Allow Control-C to interrupt FPGA configuration
972 Check for configuration errors during FPGA bitfile
973 loading. For example, abort during Virtex II
974 configuration if the INIT_B line goes low (which
975 indicated a CRC error).
979 Maximum time to wait for the INIT_B line to deassert
980 after PROB_B has been deasserted during a Virtex II
981 FPGA configuration sequence. The default time is 500 mS.
985 Maximum time to wait for BUSY to deassert during
986 Virtex II FPGA configuration. The default is 5 mS.
990 Time to wait after FPGA configuration. The default is
993 - FPGA Support: CONFIG_FPGA_COUNT
995 Specify the number of FPGA devices to support.
999 Used to specify the types of FPGA devices. For example,
1000 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1002 CFG_FPGA_PROG_FEEDBACK
1004 Enable printing of hash marks during FPGA configuration.
1008 Enable checks on FPGA configuration interface busy
1009 status by the configuration function. This option
1010 will require a board or device specific function to
1015 If defined, a function that provides delays in the FPGA
1016 configuration driver.
1018 CFG_FPGA_CHECK_CTRLC
1019 Allow Control-C to interrupt FPGA configuration
1021 CFG_FPGA_CHECK_ERROR
1023 Check for configuration errors during FPGA bitfile
1024 loading. For example, abort during Virtex II
1025 configuration if the INIT_B line goes low (which
1026 indicated a CRC error).
1030 Maximum time to wait for the INIT_B line to deassert
1031 after PROB_B has been deasserted during a Virtex II
1032 FPGA configuration sequence. The default time is 500
1037 Maximum time to wait for BUSY to deassert during
1038 Virtex II FPGA configuration. The default is 5 mS.
1040 CFG_FPGA_WAIT_CONFIG
1042 Time to wait after FPGA configuration. The default is
1045 - Configuration Management:
1048 If defined, this string will be added to the U-Boot
1049 version information (U_BOOT_VERSION)
1051 - Vendor Parameter Protection:
1053 U-Boot considers the values of the environment
1054 variables "serial#" (Board Serial Number) and
1055 "ethaddr" (Ethernet Address) to bb parameters that
1056 are set once by the board vendor / manufacturer, and
1057 protects these variables from casual modification by
1058 the user. Once set, these variables are read-only,
1059 and write or delete attempts are rejected. You can
1060 change this behviour:
1062 If CONFIG_ENV_OVERWRITE is #defined in your config
1063 file, the write protection for vendor parameters is
1064 completely disabled. Anybody can change or delete
1067 Alternatively, if you #define _both_ CONFIG_ETHADDR
1068 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1069 ethernet address is installed in the environment,
1070 which can be changed exactly ONCE by the user. [The
1071 serial# is unaffected by this, i. e. it remains
1077 Define this variable to enable the reservation of
1078 "protected RAM", i. e. RAM which is not overwritten
1079 by U-Boot. Define CONFIG_PRAM to hold the number of
1080 kB you want to reserve for pRAM. You can overwrite
1081 this default value by defining an environment
1082 variable "pram" to the number of kB you want to
1083 reserve. Note that the board info structure will
1084 still show the full amount of RAM. If pRAM is
1085 reserved, a new environment variable "mem" will
1086 automatically be defined to hold the amount of
1087 remaining RAM in a form that can be passed as boot
1088 argument to Linux, for instance like that:
1090 setenv bootargs ... mem=\$(mem)
1093 This way you can tell Linux not to use this memory,
1094 either, which results in a memory region that will
1095 not be affected by reboots.
1097 *WARNING* If your board configuration uses automatic
1098 detection of the RAM size, you must make sure that
1099 this memory test is non-destructive. So far, the
1100 following board configurations are known to be
1103 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1104 HERMES, IP860, RPXlite, LWMON, LANTEC,
1105 PCU_E, FLAGADM, TQM8260
1110 Define this variable to stop the system in case of a
1111 fatal error, so that you have to reset it manually.
1112 This is probably NOT a good idea for an embedded
1113 system where you want to system to reboot
1114 automatically as fast as possible, but it may be
1115 useful during development since you can try to debug
1116 the conditions that lead to the situation.
1118 CONFIG_NET_RETRY_COUNT
1120 This variable defines the number of retries for
1121 network operations like ARP, RARP, TFTP, or BOOTP
1122 before giving up the operation. If not defined, a
1123 default value of 5 is used.
1125 - Command Interpreter:
1128 Define this variable to enable the "hush" shell (from
1129 Busybox) as command line interpreter, thus enabling
1130 powerful command line syntax like
1131 if...then...else...fi conditionals or `&&' and '||'
1132 constructs ("shell scripts").
1134 If undefined, you get the old, much simpler behaviour
1135 with a somewhat smaller memory footprint.
1140 This defines the secondary prompt string, which is
1141 printed when the command interpreter needs more input
1142 to complete a command. Usually "> ".
1146 In the current implementation, the local variables
1147 space and global environment variables space are
1148 separated. Local variables are those you define by
1149 simply typing like `name=value'. To access a local
1150 variable later on, you have write `$name' or
1151 `${name}'; variable directly by typing say `$name' at
1154 Global environment variables are those you use
1155 setenv/printenv to work with. To run a command stored
1156 in such a variable, you need to use the run command,
1157 and you must not use the '$' sign to access them.
1159 To store commands and special characters in a
1160 variable, please use double quotation marks
1161 surrounding the whole text of the variable, instead
1162 of the backslashes before semicolons and special
1165 - Default Environment
1166 CONFIG_EXTRA_ENV_SETTINGS
1168 Define this to contain any number of null terminated
1169 strings (variable = value pairs) that will be part of
1170 the default enviroment compiled into the boot image.
1172 For example, place something like this in your
1173 board's config file:
1175 #define CONFIG_EXTRA_ENV_SETTINGS \
1179 Warning: This method is based on knowledge about the
1180 internal format how the environment is stored by the
1181 U-Boot code. This is NOT an official, exported
1182 interface! Although it is unlikely that this format
1183 will change soon, but there is no guarantee either.
1184 You better know what you are doing here.
1186 Note: overly (ab)use of the default environment is
1187 discouraged. Make sure to check other ways to preset
1188 the environment like the autoscript function or the
1191 - Show boot progress
1192 CONFIG_SHOW_BOOT_PROGRESS
1194 Defining this option allows to add some board-
1195 specific code (calling a user-provided function
1196 "show_boot_progress(int)") that enables you to show
1197 the system's boot progress on some display (for
1198 example, some LED's) on your board. At the moment,
1199 the following checkpoints are implemented:
1202 1 common/cmd_bootm.c before attempting to boot an image
1203 -1 common/cmd_bootm.c Image header has bad magic number
1204 2 common/cmd_bootm.c Image header has correct magic number
1205 -2 common/cmd_bootm.c Image header has bad checksum
1206 3 common/cmd_bootm.c Image header has correct checksum
1207 -3 common/cmd_bootm.c Image data has bad checksum
1208 4 common/cmd_bootm.c Image data has correct checksum
1209 -4 common/cmd_bootm.c Image is for unsupported architecture
1210 5 common/cmd_bootm.c Architecture check OK
1211 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1212 6 common/cmd_bootm.c Image Type check OK
1213 -6 common/cmd_bootm.c gunzip uncompression error
1214 -7 common/cmd_bootm.c Unimplemented compression type
1215 7 common/cmd_bootm.c Uncompression OK
1216 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1217 8 common/cmd_bootm.c Image Type check OK
1218 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1219 9 common/cmd_bootm.c Start initial ramdisk verification
1220 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1221 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1222 10 common/cmd_bootm.c Ramdisk header is OK
1223 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1224 11 common/cmd_bootm.c Ramdisk data has correct checksum
1225 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1226 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1227 13 common/cmd_bootm.c Start multifile image verification
1228 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1229 15 common/cmd_bootm.c All preparation done, transferring control to OS
1231 -1 common/cmd_doc.c Bad usage of "doc" command
1232 -1 common/cmd_doc.c No boot device
1233 -1 common/cmd_doc.c Unknown Chip ID on boot device
1234 -1 common/cmd_doc.c Read Error on boot device
1235 -1 common/cmd_doc.c Image header has bad magic number
1237 -1 common/cmd_ide.c Bad usage of "ide" command
1238 -1 common/cmd_ide.c No boot device
1239 -1 common/cmd_ide.c Unknown boot device
1240 -1 common/cmd_ide.c Unknown partition table
1241 -1 common/cmd_ide.c Invalid partition type
1242 -1 common/cmd_ide.c Read Error on boot device
1243 -1 common/cmd_ide.c Image header has bad magic number
1245 -1 common/cmd_nvedit.c Environment not changable, but has bad CRC
1251 [so far only for SMDK2400 and TRAB boards]
1253 - Modem support endable:
1254 CONFIG_MODEM_SUPPORT
1256 - RTS/CTS Flow control enable:
1259 - Modem debug support:
1260 CONFIG_MODEM_SUPPORT_DEBUG
1262 Enables debugging stuff (char screen[1024], dbg())
1263 for modem support. Useful only with BDI2000.
1267 In the target system modem support is enabled when a
1268 specific key (key combination) is pressed during
1269 power-on. Otherwise U-Boot will boot normally
1270 (autoboot). The key_pressed() fuction is called from
1271 board_init(). Currently key_pressed() is a dummy
1272 function, returning 1 and thus enabling modem
1275 If there are no modem init strings in the
1276 environment, U-Boot proceed to autoboot; the
1277 previous output (banner, info printfs) will be
1280 See also: doc/README.Modem
1285 Configuration Settings:
1286 -----------------------
1288 - CFG_LONGHELP: Defined when you want long help messages included;
1289 undefine this when you're short of memory.
1291 - CFG_PROMPT: This is what U-Boot prints on the console to
1292 prompt for user input.
1294 - CFG_CBSIZE: Buffer size for input from the Console
1296 - CFG_PBSIZE: Buffer size for Console output
1298 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1300 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1301 the application (usually a Linux kernel) when it is
1304 - CFG_BAUDRATE_TABLE:
1305 List of legal baudrate settings for this board.
1307 - CFG_CONSOLE_INFO_QUIET
1308 Suppress display of console information at boot.
1310 - CFG_CONSOLE_IS_IN_ENV
1311 If the board specific function
1312 extern int overwrite_console (void);
1313 returns 1, the stdin, stderr and stdout are switched to the
1314 serial port, else the settings in the environment are used.
1316 - CFG_CONSOLE_OVERWRITE_ROUTINE
1317 Enable the call to overwrite_console().
1319 - CFG_CONSOLE_ENV_OVERWRITE
1320 Enable overwrite of previous console environment settings.
1322 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1323 Begin and End addresses of the area used by the
1327 Enable an alternate, more extensive memory test.
1329 - CFG_TFTP_LOADADDR:
1330 Default load address for network file downloads
1332 - CFG_LOADS_BAUD_CHANGE:
1333 Enable temporary baudrate change while serial download
1336 Physical start address of SDRAM. _Must_ be 0 here.
1339 Physical start address of Motherboard I/O (if using a
1343 Physical start address of Flash memory.
1346 Physical start address of boot monitor code (set by
1347 make config files to be same as the text base address
1348 (TEXT_BASE) used when linking) - same as
1349 CFG_FLASH_BASE when booting from flash.
1352 Size of memory reserved for monitor code
1355 Size of DRAM reserved for malloc() use.
1358 Maximum size of memory mapped by the startup code of
1359 the Linux kernel; all data that must be processed by
1360 the Linux kernel (bd_info, boot arguments, eventually
1361 initrd image) must be put below this limit.
1363 - CFG_MAX_FLASH_BANKS:
1364 Max number of Flash memory banks
1366 - CFG_MAX_FLASH_SECT:
1367 Max number of sectors on a Flash chip
1369 - CFG_FLASH_ERASE_TOUT:
1370 Timeout for Flash erase operations (in ms)
1372 - CFG_FLASH_WRITE_TOUT:
1373 Timeout for Flash write operations (in ms)
1375 - CFG_DIRECT_FLASH_TFTP:
1377 Enable TFTP transfers directly to flash memory;
1378 without this option such a download has to be
1379 performed in two steps: (1) download to RAM, and (2)
1380 copy from RAM to flash.
1382 The two-step approach is usually more reliable, since
1383 you can check if the download worked before you erase
1384 the flash, but in some situations (when sytem RAM is
1385 too limited to allow for a tempory copy of the
1386 downloaded image) this option may be very useful.
1389 Define if the flash driver uses extra elements in the
1390 common flash structure for storing flash geometry
1392 The following definitions that deal with the placement and management
1393 of environment data (variable area); in general, we support the
1394 following configurations:
1396 - CFG_ENV_IS_IN_FLASH:
1398 Define this if the environment is in flash memory.
1400 a) The environment occupies one whole flash sector, which is
1401 "embedded" in the text segment with the U-Boot code. This
1402 happens usually with "bottom boot sector" or "top boot
1403 sector" type flash chips, which have several smaller
1404 sectors at the start or the end. For instance, such a
1405 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1406 such a case you would place the environment in one of the
1407 4 kB sectors - with U-Boot code before and after it. With
1408 "top boot sector" type flash chips, you would put the
1409 environment in one of the last sectors, leaving a gap
1410 between U-Boot and the environment.
1414 Offset of environment data (variable area) to the
1415 beginning of flash memory; for instance, with bottom boot
1416 type flash chips the second sector can be used: the offset
1417 for this sector is given here.
1419 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1423 This is just another way to specify the start address of
1424 the flash sector containing the environment (instead of
1427 - CFG_ENV_SECT_SIZE:
1429 Size of the sector containing the environment.
1432 b) Sometimes flash chips have few, equal sized, BIG sectors.
1433 In such a case you don't want to spend a whole sector for
1438 If you use this in combination with CFG_ENV_IS_IN_FLASH
1439 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1440 of this flash sector for the environment. This saves
1441 memory for the RAM copy of the environment.
1443 It may also save flash memory if you decide to use this
1444 when your environment is "embedded" within U-Boot code,
1445 since then the remainder of the flash sector could be used
1446 for U-Boot code. It should be pointed out that this is
1447 STRONGLY DISCOURAGED from a robustness point of view:
1448 updating the environment in flash makes it always
1449 necessary to erase the WHOLE sector. If something goes
1450 wrong before the contents has been restored from a copy in
1451 RAM, your target system will be dead.
1453 - CFG_ENV_ADDR_REDUND
1456 These settings describe a second storage area used to hold
1457 a redundand copy of the environment data, so that there is
1458 a valid backup copy in case there is a power failur during
1459 a "saveenv" operation.
1461 BE CAREFUL! Any changes to the flash layout, and some changes to the
1462 source code will make it necessary to adapt <board>/u-boot.lds*
1466 - CFG_ENV_IS_IN_NVRAM:
1468 Define this if you have some non-volatile memory device
1469 (NVRAM, battery buffered SRAM) which you want to use for the
1475 These two #defines are used to determin the memory area you
1476 want to use for environment. It is assumed that this memory
1477 can just be read and written to, without any special
1480 BE CAREFUL! The first access to the environment happens quite early
1481 in U-Boot initalization (when we try to get the setting of for the
1482 console baudrate). You *MUST* have mappend your NVRAM area then, or
1485 Please note that even with NVRAM we still use a copy of the
1486 environment in RAM: we could work on NVRAM directly, but we want to
1487 keep settings there always unmodified except somebody uses "saveenv"
1488 to save the current settings.
1491 - CFG_ENV_IS_IN_EEPROM:
1493 Use this if you have an EEPROM or similar serial access
1494 device and a driver for it.
1499 These two #defines specify the offset and size of the
1500 environment area within the total memory of your EEPROM.
1502 - CFG_I2C_EEPROM_ADDR:
1503 If defined, specified the chip address of the EEPROM device.
1504 The default address is zero.
1506 - CFG_EEPROM_PAGE_WRITE_BITS:
1507 If defined, the number of bits used to address bytes in a
1508 single page in the EEPROM device. A 64 byte page, for example
1509 would require six bits.
1511 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1512 If defined, the number of milliseconds to delay between
1513 page writes. The default is zero milliseconds.
1515 - CFG_I2C_EEPROM_ADDR_LEN:
1516 The length in bytes of the EEPROM memory array address. Note
1517 that this is NOT the chip address length!
1520 The size in bytes of the EEPROM device.
1523 - CFG_SPI_INIT_OFFSET
1525 Defines offset to the initial SPI buffer area in DPRAM. The
1526 area is used at an early stage (ROM part) if the environment
1527 is configured to reside in the SPI EEPROM: We need a 520 byte
1528 scratch DPRAM area. It is used between the two initialization
1529 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1530 to be a good choice since it makes it far enough from the
1531 start of the data area as well as from the stack pointer.
1533 Please note that the environment is read-only as long as the monitor
1534 has been relocated to RAM and a RAM copy of the environment has been
1535 created; also, when using EEPROM you will have to use getenv_r()
1536 until then to read environment variables.
1538 The environment is protected by a CRC32 checksum. Before the monitor
1539 is relocated into RAM, as a result of a bad CRC you will be working
1540 with the compiled-in default environment - *silently*!!! [This is
1541 necessary, because the first environment variable we need is the
1542 "baudrate" setting for the console - if we have a bad CRC, we don't
1543 have any device yet where we could complain.]
1545 Note: once the monitor has been relocated, then it will complain if
1546 the default environment is used; a new CRC is computed as soon as you
1547 use the "saveenv" command to store a valid environment.
1550 Low Level (hardware related) configuration options:
1551 ---------------------------------------------------
1553 - CFG_CACHELINE_SIZE:
1554 Cache Line Size of the CPU.
1557 Default address of the IMMR after system reset.
1558 Needed on some 8260 systems (MPC8260ADS and RPXsuper)
1559 to be able to adjust the position of the IMMR
1560 register after a reset.
1562 - Floppy Disk Support:
1563 CFG_FDC_DRIVE_NUMBER
1565 the default drive number (default value 0)
1569 defines the spacing between fdc chipset registers
1574 defines the offset of register from address. It
1575 depends on which part of the data bus is connected to
1576 the fdc chipset. (default value 0)
1578 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1579 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1582 if CFG_FDC_HW_INIT is defined, then the function
1583 fdc_hw_init() is called at the beginning of the FDC
1584 setup. fdc_hw_init() must be provided by the board
1585 source code. It is used to make hardware dependant
1588 - CFG_IMMR: Physical address of the Internal Memory Mapped
1589 Register; DO NOT CHANGE! (11-4)
1590 [MPC8xx systems only]
1592 - CFG_INIT_RAM_ADDR:
1594 Start address of memory area tha can be used for
1595 initial data and stack; please note that this must be
1596 writable memory that is working WITHOUT special
1597 initialization, i. e. you CANNOT use normal RAM which
1598 will become available only after programming the
1599 memory controller and running certain initialization
1602 U-Boot uses the following memory types:
1603 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1604 - MPC824X: data cache
1605 - PPC4xx: data cache
1607 - CFG_GBL_DATA_OFFSET:
1609 Offset of the initial data structure in the memory
1610 area defined by CFG_INIT_RAM_ADDR. Usually
1611 CFG_GBL_DATA_OFFSET is chosen such that the initial
1612 data is located at the end of the available space
1613 (sometimes written as (CFG_INIT_RAM_END -
1614 CFG_INIT_DATA_SIZE), and the initial stack is just
1615 below that area (growing from (CFG_INIT_RAM_ADDR +
1616 CFG_GBL_DATA_OFFSET) downward.
1619 On the MPC824X (or other systems that use the data
1620 cache for initial memory) the address chosen for
1621 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1622 point to an otherwise UNUSED address space between
1623 the top of RAM and the start of the PCI space.
1625 - CFG_SIUMCR: SIU Module Configuration (11-6)
1627 - CFG_SYPCR: System Protection Control (11-9)
1629 - CFG_TBSCR: Time Base Status and Control (11-26)
1631 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1633 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1635 - CFG_SCCR: System Clock and reset Control Register (15-27)
1637 - CFG_OR_TIMING_SDRAM:
1641 periodic timer for refresh
1643 - CFG_DER: Debug Event Register (37-47)
1645 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1646 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1647 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1649 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1651 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1652 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1653 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1654 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1656 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1657 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1658 Machine Mode Register and Memory Periodic Timer
1659 Prescaler definitions (SDRAM timing)
1661 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1662 enable I2C microcode relocation patch (MPC8xx);
1663 define relocation offset in DPRAM [DSP2]
1665 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1666 enable SPI microcode relocation patch (MPC8xx);
1667 define relocation offset in DPRAM [SCC4]
1670 Use OSCM clock mode on MBX8xx board. Be careful,
1671 wrong setting might damage your board. Read
1672 doc/README.MBX before setting this variable!
1674 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1675 Offset of the bootmode word in DPRAM used by post
1676 (Power On Self Tests). This definition overrides
1677 #define'd default value in commproc.h resp.
1680 Building the Software:
1681 ======================
1683 Building U-Boot has been tested in native PPC environments (on a
1684 PowerBook G3 running LinuxPPC 2000) and in cross environments
1685 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1688 If you are not using a native PPC environment, it is assumed that you
1689 have the GNU cross compiling tools available in your path and named
1690 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1691 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1692 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1695 CROSS_COMPILE = ppc_4xx-
1698 U-Boot is intended to be simple to build. After installing the
1699 sources you must configure U-Boot for one specific board type. This
1704 where "NAME_config" is the name of one of the existing
1705 configurations; the following names are supported:
1707 ADCIOP_config GTH_config TQM850L_config
1708 ADS860_config IP860_config TQM855L_config
1709 AR405_config IVML24_config TQM860L_config
1710 CANBT_config IVMS8_config WALNUT405_config
1711 CPCI405_config LANTEC_config cogent_common_config
1712 CPCIISER4_config MBX_config cogent_mpc8260_config
1713 CU824_config MBX860T_config cogent_mpc8xx_config
1714 ESTEEM192E_config RPXlite_config hermes_config
1715 ETX094_config RPXsuper_config hymod_config
1716 FADS823_config SM850_config lwmon_config
1717 FADS850SAR_config SPD823TS_config pcu_e_config
1718 FADS860T_config SXNI855T_config rsdproto_config
1719 FPS850L_config Sandpoint8240_config sbc8260_config
1720 GENIETV_config TQM823L_config PIP405_config
1721 GEN860T_config EBONY_config FPS860L_config
1722 ELPT860_config cmi_mpc5xx_config
1724 Note: for some board special configuration names may exist; check if
1725 additional information is available from the board vendor; for
1726 instance, the TQM8xxL systems run normally at 50 MHz and use a
1727 SCC for 10baseT ethernet; there are also systems with 80 MHz
1728 CPU clock, and an optional Fast Ethernet module is available
1729 for CPU's with FEC. You can select such additional "features"
1730 when chosing the configuration, i. e.
1733 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
1735 make TQM860L_FEC_config
1736 - will configure for a TQM860L at 50MHz with FEC for ethernet
1738 make TQM860L_80MHz_config
1739 - will configure for a TQM860L at 80 MHz, with normal 10baseT
1742 make TQM860L_FEC_80MHz_config
1743 - will configure for a TQM860L at 80 MHz with FEC for ethernet
1745 make TQM823L_LCD_config
1746 - will configure for a TQM823L with U-Boot console on LCD
1748 make TQM823L_LCD_80MHz_config
1749 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
1755 Finally, type "make all", and you should get some working U-Boot
1756 images ready for downlod to / installation on your system:
1758 - "u-boot.bin" is a raw binary image
1759 - "u-boot" is an image in ELF binary format
1760 - "u-boot.srec" is in Motorola S-Record format
1763 Please be aware that the Makefiles assume you are using GNU make, so
1764 for instance on NetBSD you might need to use "gmake" instead of
1768 If the system board that you have is not listed, then you will need
1769 to port U-Boot to your hardware platform. To do this, follow these
1772 1. Add a new configuration option for your board to the toplevel
1773 "Makefile" and to the "MAKEALL" script, using the existing
1774 entries as examples. Note that here and at many other places
1775 boards and other names are listed alphabetically sorted. Please
1777 2. Create a new directory to hold your board specific code. Add any
1778 files you need. In your board directory, you will need at least
1779 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
1780 3. Create a new configuration file "include/configs/<board>.h" for
1782 3. If you're porting U-Boot to a new CPU, then also create a new
1783 directory to hold your CPU specific code. Add any files you need.
1784 4. Run "make <board>_config" with your new name.
1785 5. Type "make", and you should get a working "u-boot.srec" file
1786 to be installed on your target system.
1787 6. Debug and solve any problems that might arise.
1788 [Of course, this last step is much harder than it sounds.]
1791 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
1792 ==============================================================
1794 If you have modified U-Boot sources (for instance added a new board
1795 or support for new devices, a new CPU, etc.) you are expected to
1796 provide feedback to the other developers. The feedback normally takes
1797 the form of a "patch", i. e. a context diff against a certain (latest
1798 official or latest in CVS) version of U-Boot sources.
1800 But before you submit such a patch, please verify that your modifi-
1801 cation did not break existing code. At least make sure that *ALL* of
1802 the supported boards compile WITHOUT ANY compiler warnings. To do so,
1803 just run the "MAKEALL" script, which will configure and build U-Boot
1804 for ALL supported system. Be warned, this will take a while. You can
1805 select which (cross) compiler to use py passing a `CROSS_COMPILE'
1806 environment variable to the script, i. e. to use the cross tools from
1807 MontaVista's Hard Hat Linux you can type
1809 CROSS_COMPILE=ppc_8xx- MAKEALL
1811 or to build on a native PowerPC system you can type
1813 CROSS_COMPILE=' ' MAKEALL
1815 See also "U-Boot Porting Guide" below.
1819 Monitor Commands - Overview:
1820 ============================
1822 go - start application at address 'addr'
1823 run - run commands in an environment variable
1824 bootm - boot application image from memory
1825 bootp - boot image via network using BootP/TFTP protocol
1826 tftpboot- boot image via network using TFTP protocol
1827 and env variables "ipaddr" and "serverip"
1828 (and eventually "gatewayip")
1829 rarpboot- boot image via network using RARP/TFTP protocol
1830 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
1831 loads - load S-Record file over serial line
1832 loadb - load binary file over serial line (kermit mode)
1834 mm - memory modify (auto-incrementing)
1835 nm - memory modify (constant address)
1836 mw - memory write (fill)
1838 cmp - memory compare
1839 crc32 - checksum calculation
1840 imd - i2c memory display
1841 imm - i2c memory modify (auto-incrementing)
1842 inm - i2c memory modify (constant address)
1843 imw - i2c memory write (fill)
1844 icrc32 - i2c checksum calculation
1845 iprobe - probe to discover valid I2C chip addresses
1846 iloop - infinite loop on address range
1847 isdram - print SDRAM configuration information
1848 sspi - SPI utility commands
1849 base - print or set address offset
1850 printenv- print environment variables
1851 setenv - set environment variables
1852 saveenv - save environment variables to persistent storage
1853 protect - enable or disable FLASH write protection
1854 erase - erase FLASH memory
1855 flinfo - print FLASH memory information
1856 bdinfo - print Board Info structure
1857 iminfo - print header information for application image
1858 coninfo - print console devices and informations
1859 ide - IDE sub-system
1860 loop - infinite loop on address range
1861 mtest - simple RAM test
1862 icache - enable or disable instruction cache
1863 dcache - enable or disable data cache
1864 reset - Perform RESET of the CPU
1865 echo - echo args to console
1866 version - print monitor version
1867 help - print online help
1868 ? - alias for 'help'
1871 Monitor Commands - Detailed Description:
1872 ========================================
1876 For now: just type "help <command>".
1879 Environment Variables:
1880 ======================
1882 U-Boot supports user configuration using Environment Variables which
1883 can be made persistent by saving to Flash memory.
1885 Environment Variables are set using "setenv", printed using
1886 "printenv", and saved to Flash using "saveenv". Using "setenv"
1887 without a value can be used to delete a variable from the
1888 environment. As long as you don't save the environment you are
1889 working with an in-memory copy. In case the Flash area containing the
1890 environment is erased by accident, a default environment is provided.
1892 Some configuration options can be set using Environment Variables:
1894 baudrate - see CONFIG_BAUDRATE
1896 bootdelay - see CONFIG_BOOTDELAY
1898 bootcmd - see CONFIG_BOOTCOMMAND
1900 bootargs - Boot arguments when booting an RTOS image
1902 bootfile - Name of the image to load with TFTP
1904 autoload - if set to "no" (any string beginning with 'n'),
1905 "bootp" will just load perform a lookup of the
1906 configuration from the BOOTP server, but not try to
1907 load any image using TFTP
1909 autostart - if set to "yes", an image loaded using the "bootp",
1910 "rarpboot", "tftpboot" or "diskboot" commands will
1911 be automatically started (by internally calling
1914 initrd_high - restrict positioning of initrd images:
1915 If this variable is not set, initrd images will be
1916 copied to the highest possible address in RAM; this
1917 is usually what you want since it allows for
1918 maximum initrd size. If for some reason you want to
1919 make sure that the initrd image is loaded below the
1920 CFG_BOOTMAPSZ limit, you can set this environment
1921 variable to a value of "no" or "off" or "0".
1922 Alternatively, you can set it to a maximum upper
1923 address to use (U-Boot will still check that it
1924 does not overwrite the U-Boot stack and data).
1926 For instance, when you have a system with 16 MB
1927 RAM, and want to reseve 4 MB from use by Linux,
1928 you can do this by adding "mem=12M" to the value of
1929 the "bootargs" variable. However, now you must make
1930 sure, that the initrd image is placed in the first
1931 12 MB as well - this can be done with
1933 setenv initrd_high 00c00000
1935 ipaddr - IP address; needed for tftpboot command
1937 loadaddr - Default load address for commands like "bootp",
1938 "rarpboot", "tftpboot", "loadb" or "diskboot"
1940 loads_echo - see CONFIG_LOADS_ECHO
1942 serverip - TFTP server IP address; needed for tftpboot command
1944 bootretry - see CONFIG_BOOT_RETRY_TIME
1946 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
1948 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
1951 The following environment variables may be used and automatically
1952 updated by the network boot commands ("bootp" and "rarpboot"),
1953 depending the information provided by your boot server:
1955 bootfile - see above
1956 dnsip - IP address of your Domain Name Server
1957 gatewayip - IP address of the Gateway (Router) to use
1958 hostname - Target hostname
1960 netmask - Subnet Mask
1961 rootpath - Pathname of the root filesystem on the NFS server
1962 serverip - see above
1965 There are two special Environment Variables:
1967 serial# - contains hardware identification information such
1968 as type string and/or serial number
1969 ethaddr - Ethernet address
1971 These variables can be set only once (usually during manufacturing of
1972 the board). U-Boot refuses to delete or overwrite these variables
1973 once they have been set once.
1976 Please note that changes to some configuration parameters may take
1977 only effect after the next boot (yes, that's just like Windoze :-).
1980 Note for Redundant Ethernet Interfaces:
1981 =======================================
1983 Some boards come with redundand ethernet interfaces; U-Boot supports
1984 such configurations and is capable of automatic selection of a
1985 "working" interface when needed. MAC assignemnt works as follows:
1987 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
1988 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
1989 "eth1addr" (=>eth1), "eth2addr", ...
1991 If the network interface stores some valid MAC address (for instance
1992 in SROM), this is used as default address if there is NO correspon-
1993 ding setting in the environment; if the corresponding environment
1994 variable is set, this overrides the settings in the card; that means:
1996 o If the SROM has a valid MAC address, and there is no address in the
1997 environment, the SROM's address is used.
1999 o If there is no valid address in the SROM, and a definition in the
2000 environment exists, then the value from the environment variable is
2003 o If both the SROM and the environment contain a MAC address, and
2004 both addresses are the same, this MAC address is used.
2006 o If both the SROM and the environment contain a MAC address, and the
2007 addresses differ, the value from the environment is used and a
2010 o If neither SROM nor the environment contain a MAC address, an error
2018 The "boot" commands of this monitor operate on "image" files which
2019 can be basicly anything, preceeded by a special header; see the
2020 definitions in include/image.h for details; basicly, the header
2021 defines the following image properties:
2023 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2024 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2026 Currently supported: Linux, NetBSD, VxWorks, QNX).
2027 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2028 IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2029 Currently supported: PowerPC).
2030 * Compression Type (Provisions for uncompressed, gzip, bzip2;
2031 Currently supported: uncompressed, gzip).
2037 The header is marked by a special Magic Number, and both the header
2038 and the data portions of the image are secured against corruption by
2045 Although U-Boot should support any OS or standalone application
2046 easily, Linux has always been in the focus during the design of
2049 U-Boot includes many features that so far have been part of some
2050 special "boot loader" code within the Linux kernel. Also, any
2051 "initrd" images to be used are no longer part of one big Linux image;
2052 instead, kernel and "initrd" are separate images. This implementation
2053 serves serveral purposes:
2055 - the same features can be used for other OS or standalone
2056 applications (for instance: using compressed images to reduce the
2057 Flash memory footprint)
2059 - it becomes much easier to port new Linux kernel versions because
2060 lots of low-level, hardware dependend stuff are done by U-Boot
2062 - the same Linux kernel image can now be used with different "initrd"
2063 images; of course this also means that different kernel images can
2064 be run with the same "initrd". This makes testing easier (you don't
2065 have to build a new "zImage.initrd" Linux image when you just
2066 change a file in your "initrd"). Also, a field-upgrade of the
2067 software is easier now.
2073 Porting Linux to U-Boot based systems:
2074 ---------------------------------------
2076 U-Boot cannot save you from doing all the necessary modifications to
2077 configure the Linux device drivers for use with your target hardware
2078 (no, we don't intend to provide a full virtual machine interface to
2081 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2083 Just make sure your machine specific header file (for instance
2084 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2085 Information structure as we define in include/u-boot.h, and make
2086 sure that your definition of IMAP_ADDR uses the same value as your
2087 U-Boot configuration in CFG_IMMR.
2090 Configuring the Linux kernel:
2091 -----------------------------
2093 No specific requirements for U-Boot. Make sure you have some root
2094 device (initial ramdisk, NFS) for your target system.
2097 Building a Linux Image:
2098 -----------------------
2100 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2101 not used. If you use recent kernel source, a new build target
2102 "uImage" will exist which automatically builds an image usable by
2103 U-Boot. Most older kernels also have support for a "pImage" target,
2104 which was introduced for our predecessor project PPCBoot and uses a
2105 100% compatible format.
2114 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2115 encapsulate a compressed Linux kernel image with header information,
2116 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2118 * build a standard "vmlinux" kernel image (in ELF binary format):
2120 * convert the kernel into a raw binary image:
2122 ${CROSS_COMPILE}-objcopy -O binary \
2123 -R .note -R .comment \
2124 -S vmlinux linux.bin
2126 * compress the binary image:
2130 * package compressed binary image for U-Boot:
2132 mkimage -A ppc -O linux -T kernel -C gzip \
2133 -a 0 -e 0 -n "Linux Kernel Image" \
2134 -d linux.bin.gz uImage
2137 The "mkimage" tool can also be used to create ramdisk images for use
2138 with U-Boot, either separated from the Linux kernel image, or
2139 combined into one file. "mkimage" encapsulates the images with a 64
2140 byte header containing information about target architecture,
2141 operating system, image type, compression method, entry points, time
2142 stamp, CRC32 checksums, etc.
2144 "mkimage" can be called in two ways: to verify existing images and
2145 print the header information, or to build new images.
2147 In the first form (with "-l" option) mkimage lists the information
2148 contained in the header of an existing U-Boot image; this includes
2149 checksum verification:
2151 tools/mkimage -l image
2152 -l ==> list image header information
2154 The second form (with "-d" option) is used to build a U-Boot image
2155 from a "data file" which is used as image payload:
2157 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2158 -n name -d data_file image
2159 -A ==> set architecture to 'arch'
2160 -O ==> set operating system to 'os'
2161 -T ==> set image type to 'type'
2162 -C ==> set compression type 'comp'
2163 -a ==> set load address to 'addr' (hex)
2164 -e ==> set entry point to 'ep' (hex)
2165 -n ==> set image name to 'name'
2166 -d ==> use image data from 'datafile'
2168 Right now, all Linux kernels use the same load address (0x00000000),
2169 but the entry point address depends on the kernel version:
2171 - 2.2.x kernels have the entry point at 0x0000000C,
2172 - 2.3.x and later kernels have the entry point at 0x00000000.
2174 So a typical call to build a U-Boot image would read:
2176 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2177 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2178 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2179 > examples/uImage.TQM850L
2180 Image Name: 2.4.4 kernel for TQM850L
2181 Created: Wed Jul 19 02:34:59 2000
2182 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2183 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2184 Load Address: 0x00000000
2185 Entry Point: 0x00000000
2187 To verify the contents of the image (or check for corruption):
2189 -> tools/mkimage -l examples/uImage.TQM850L
2190 Image Name: 2.4.4 kernel for TQM850L
2191 Created: Wed Jul 19 02:34:59 2000
2192 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2193 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2194 Load Address: 0x00000000
2195 Entry Point: 0x00000000
2197 NOTE: for embedded systems where boot time is critical you can trade
2198 speed for memory and install an UNCOMPRESSED image instead: this
2199 needs more space in Flash, but boots much faster since it does not
2200 need to be uncompressed:
2202 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2203 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2204 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2205 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2206 > examples/uImage.TQM850L-uncompressed
2207 Image Name: 2.4.4 kernel for TQM850L
2208 Created: Wed Jul 19 02:34:59 2000
2209 Image Type: PowerPC Linux Kernel Image (uncompressed)
2210 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2211 Load Address: 0x00000000
2212 Entry Point: 0x00000000
2215 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2216 when your kernel is intended to use an initial ramdisk:
2218 -> tools/mkimage -n 'Simple Ramdisk Image' \
2219 > -A ppc -O linux -T ramdisk -C gzip \
2220 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2221 Image Name: Simple Ramdisk Image
2222 Created: Wed Jan 12 14:01:50 2000
2223 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2224 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2225 Load Address: 0x00000000
2226 Entry Point: 0x00000000
2229 Installing a Linux Image:
2230 -------------------------
2232 To downloading a U-Boot image over the serial (console) interface,
2233 you must convert the image to S-Record format:
2235 objcopy -I binary -O srec examples/image examples/image.srec
2237 The 'objcopy' does not understand the information in the U-Boot
2238 image header, so the resulting S-Record file will be relative to
2239 address 0x00000000. To load it to a given address, you need to
2240 specify the target address as 'offset' parameter with the 'loads'
2243 Example: install the image to address 0x40100000 (which on the
2244 TQM8xxL is in the first Flash bank):
2246 => erase 40100000 401FFFFF
2252 ## Ready for S-Record download ...
2253 ~>examples/image.srec
2254 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2256 15989 15990 15991 15992
2257 [file transfer complete]
2259 ## Start Addr = 0x00000000
2262 You can check the success of the download using the 'iminfo' command;
2263 this includes a checksum verification so you can be sure no data
2264 corruption happened:
2268 ## Checking Image at 40100000 ...
2269 Image Name: 2.2.13 for initrd on TQM850L
2270 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2271 Data Size: 335725 Bytes = 327 kB = 0 MB
2272 Load Address: 00000000
2273 Entry Point: 0000000c
2274 Verifying Checksum ... OK
2281 The "bootm" command is used to boot an application that is stored in
2282 memory (RAM or Flash). In case of a Linux kernel image, the contents
2283 of the "bootargs" environment variable is passed to the kernel as
2284 parameters. You can check and modify this variable using the
2285 "printenv" and "setenv" commands:
2288 => printenv bootargs
2289 bootargs=root=/dev/ram
2291 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2293 => printenv bootargs
2294 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2297 ## Booting Linux kernel at 40020000 ...
2298 Image Name: 2.2.13 for NFS on TQM850L
2299 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2300 Data Size: 381681 Bytes = 372 kB = 0 MB
2301 Load Address: 00000000
2302 Entry Point: 0000000c
2303 Verifying Checksum ... OK
2304 Uncompressing Kernel Image ... OK
2305 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
2306 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2307 time_init: decrementer frequency = 187500000/60
2308 Calibrating delay loop... 49.77 BogoMIPS
2309 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2312 If you want to boot a Linux kernel with initial ram disk, you pass
2313 the memory addreses of both the kernel and the initrd image (PPBCOOT
2314 format!) to the "bootm" command:
2316 => imi 40100000 40200000
2318 ## Checking Image at 40100000 ...
2319 Image Name: 2.2.13 for initrd on TQM850L
2320 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2321 Data Size: 335725 Bytes = 327 kB = 0 MB
2322 Load Address: 00000000
2323 Entry Point: 0000000c
2324 Verifying Checksum ... OK
2326 ## Checking Image at 40200000 ...
2327 Image Name: Simple Ramdisk Image
2328 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2329 Data Size: 566530 Bytes = 553 kB = 0 MB
2330 Load Address: 00000000
2331 Entry Point: 00000000
2332 Verifying Checksum ... OK
2334 => bootm 40100000 40200000
2335 ## Booting Linux kernel at 40100000 ...
2336 Image Name: 2.2.13 for initrd on TQM850L
2337 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2338 Data Size: 335725 Bytes = 327 kB = 0 MB
2339 Load Address: 00000000
2340 Entry Point: 0000000c
2341 Verifying Checksum ... OK
2342 Uncompressing Kernel Image ... OK
2343 ## Loading RAMDisk Image at 40200000 ...
2344 Image Name: Simple Ramdisk Image
2345 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2346 Data Size: 566530 Bytes = 553 kB = 0 MB
2347 Load Address: 00000000
2348 Entry Point: 00000000
2349 Verifying Checksum ... OK
2350 Loading Ramdisk ... OK
2351 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
2352 Boot arguments: root=/dev/ram
2353 time_init: decrementer frequency = 187500000/60
2354 Calibrating delay loop... 49.77 BogoMIPS
2356 RAMDISK: Compressed image found at block 0
2357 VFS: Mounted root (ext2 filesystem).
2361 More About U-Boot Image Types:
2362 ------------------------------
2364 U-Boot supports the following image types:
2366 "Standalone Programs" are directly runnable in the environment
2367 provided by U-Boot; it is expected that (if they behave
2368 well) you can continue to work in U-Boot after return from
2369 the Standalone Program.
2370 "OS Kernel Images" are usually images of some Embedded OS which
2371 will take over control completely. Usually these programs
2372 will install their own set of exception handlers, device
2373 drivers, set up the MMU, etc. - this means, that you cannot
2374 expect to re-enter U-Boot except by resetting the CPU.
2375 "RAMDisk Images" are more or less just data blocks, and their
2376 parameters (address, size) are passed to an OS kernel that is
2378 "Multi-File Images" contain several images, typically an OS
2379 (Linux) kernel image and one or more data images like
2380 RAMDisks. This construct is useful for instance when you want
2381 to boot over the network using BOOTP etc., where the boot
2382 server provides just a single image file, but you want to get
2383 for instance an OS kernel and a RAMDisk image.
2385 "Multi-File Images" start with a list of image sizes, each
2386 image size (in bytes) specified by an "uint32_t" in network
2387 byte order. This list is terminated by an "(uint32_t)0".
2388 Immediately after the terminating 0 follow the images, one by
2389 one, all aligned on "uint32_t" boundaries (size rounded up to
2390 a multiple of 4 bytes).
2392 "Firmware Images" are binary images containing firmware (like
2393 U-Boot or FPGA images) which usually will be programmed to
2396 "Script files" are command sequences that will be executed by
2397 U-Boot's command interpreter; this feature is especially
2398 useful when you configure U-Boot to use a real shell (hush)
2399 as command interpreter.
2405 One of the features of U-Boot is that you can dynamically load and
2406 run "standalone" applications, which can use some resources of
2407 U-Boot like console I/O functions or interrupt services.
2409 Two simple examples are included with the sources:
2414 'examples/hello_world.c' contains a small "Hello World" Demo
2415 application; it is automatically compiled when you build U-Boot.
2416 It's configured to run at address 0x00040004, so you can play with it
2420 ## Ready for S-Record download ...
2421 ~>examples/hello_world.srec
2422 1 2 3 4 5 6 7 8 9 10 11 ...
2423 [file transfer complete]
2425 ## Start Addr = 0x00040004
2427 => go 40004 Hello World! This is a test.
2428 ## Starting application at 0x00040004 ...
2439 Hit any key to exit ...
2441 ## Application terminated, rc = 0x0
2443 Another example, which demonstrates how to register a CPM interrupt
2444 handler with the U-Boot code, can be found in 'examples/timer.c'.
2445 Here, a CPM timer is set up to generate an interrupt every second.
2446 The interrupt service routine is trivial, just printing a '.'
2447 character, but this is just a demo program. The application can be
2448 controlled by the following keys:
2450 ? - print current values og the CPM Timer registers
2451 b - enable interrupts and start timer
2452 e - stop timer and disable interrupts
2453 q - quit application
2456 ## Ready for S-Record download ...
2457 ~>examples/timer.srec
2458 1 2 3 4 5 6 7 8 9 10 11 ...
2459 [file transfer complete]
2461 ## Start Addr = 0x00040004
2464 ## Starting application at 0x00040004 ...
2467 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2470 [q, b, e, ?] Set interval 1000000 us
2473 [q, b, e, ?] ........
2474 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2477 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2480 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2483 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2485 [q, b, e, ?] ...Stopping timer
2487 [q, b, e, ?] ## Application terminated, rc = 0x0
2494 Over time, many people have reported problems when trying to used the
2495 "minicom" terminal emulation program for serial download. I (wd)
2496 consider minicom to be broken, and recommend not to use it. Under
2497 Unix, I recommend to use CKermit for general purpose use (and
2498 especially for kermit binary protocol download ("loadb" command), and
2499 use "cu" for S-Record download ("loads" command).
2504 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2505 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2507 Building requires a cross environment; it is known to work on
2508 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2509 need gmake since the Makefiles are not compatible with BSD make).
2510 Note that the cross-powerpc package does not install include files;
2511 attempting to build U-Boot will fail because <machine/ansi.h> is
2512 missing. This file has to be installed and patched manually:
2514 # cd /usr/pkg/cross/powerpc-netbsd/include
2516 # ln -s powerpc machine
2517 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2518 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2520 Native builds *don't* work due to incompatibilities between native
2521 and U-Boot include files.
2523 Booting assumes that (the first part of) the image booted is a
2524 stage-2 loader which in turn loads and then invokes the kernel
2525 proper. Loader sources will eventually appear in the NetBSD source
2526 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2527 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2531 Implementation Internals:
2532 =========================
2534 The following is not intended to be a complete description of every
2535 implementation detail. However, it should help to understand the
2536 inner workings of U-Boot and make it easier to port it to custom
2540 Initial Stack, Global Data:
2541 ---------------------------
2543 The implementation of U-Boot is complicated by the fact that U-Boot
2544 starts running out of ROM (flash memory), usually without access to
2545 system RAM (because the memory controller is not initialized yet).
2546 This means that we don't have writable Data or BSS segments, and BSS
2547 is not initialized as zero. To be able to get a C environment working
2548 at all, we have to allocate at least a minimal stack. Implementation
2549 options for this are defined and restricted by the CPU used: Some CPU
2550 models provide on-chip memory (like the IMMR area on MPC8xx and
2551 MPC826x processors), on others (parts of) the data cache can be
2552 locked as (mis-) used as memory, etc.
2554 Chris Hallinan posted a good summy of these issues to the
2555 u-boot-users mailing list:
2557 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2558 From: "Chris Hallinan" <clh@net1plus.com>
2559 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2562 Correct me if I'm wrong, folks, but the way I understand it
2563 is this: Using DCACHE as initial RAM for Stack, etc, does not
2564 require any physical RAM backing up the cache. The cleverness
2565 is that the cache is being used as a temporary supply of
2566 necessary storage before the SDRAM controller is setup. It's
2567 beyond the scope of this list to expain the details, but you
2568 can see how this works by studying the cache architecture and
2569 operation in the architecture and processor-specific manuals.
2571 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2572 is another option for the system designer to use as an
2573 initial stack/ram area prior to SDRAM being available. Either
2574 option should work for you. Using CS 4 should be fine if your
2575 board designers haven't used it for something that would
2576 cause you grief during the initial boot! It is frequently not
2579 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2580 with your processor/board/system design. The default value
2581 you will find in any recent u-boot distribution in
2582 Walnut405.h should work for you. I'd set it to a value larger
2583 than your SDRAM module. If you have a 64MB SDRAM module, set
2584 it above 400_0000. Just make sure your board has no resources
2585 that are supposed to respond to that address! That code in
2586 start.S has been around a while and should work as is when
2587 you get the config right.
2592 It is essential to remember this, since it has some impact on the C
2593 code for the initialization procedures:
2595 * Initialized global data (data segment) is read-only. Do not attempt
2598 * Do not use any unitialized global data (or implicitely initialized
2599 as zero data - BSS segment) at all - this is undefined, initiali-
2600 zation is performed later (when relocationg to RAM).
2602 * Stack space is very limited. Avoid big data buffers or things like
2605 Having only the stack as writable memory limits means we cannot use
2606 normal global data to share information beween the code. But it
2607 turned out that the implementation of U-Boot can be greatly
2608 simplified by making a global data structure (gd_t) available to all
2609 functions. We could pass a pointer to this data as argument to _all_
2610 functions, but this would bloat the code. Instead we use a feature of
2611 the GCC compiler (Global Register Variables) to share the data: we
2612 place a pointer (gd) to the global data into a register which we
2613 reserve for this purpose.
2615 When chosing a register for such a purpose we are restricted by the
2616 relevant (E)ABI specifications for the current architecture, and by
2617 GCC's implementation.
2619 For PowerPC, the following registers have specific use:
2622 R3-R4: parameter passing and return values
2623 R5-R10: parameter passing
2624 R13: small data area pointer
2628 (U-Boot also uses R14 as internal GOT pointer.)
2630 ==> U-Boot will use R29 to hold a pointer to the global data
2632 Note: on PPC, we could use a static initializer (since the
2633 address of the global data structure is known at compile time),
2634 but it turned out that reserving a register results in somewhat
2635 smaller code - although the code savings are not that big (on
2636 average for all boards 752 bytes for the whole U-Boot image,
2637 624 text + 127 data).
2639 On ARM, the following registers are used:
2641 R0: function argument word/integer result
2642 R1-R3: function argument word
2644 R10: stack limit (used only if stack checking if enabled)
2645 R11: argument (frame) pointer
2646 R12: temporary workspace
2649 R15: program counter
2651 ==> U-Boot will use R8 to hold a pointer to the global data
2658 U-Boot runs in system state and uses physical addresses, i.e. the
2659 MMU is not used either for address mapping nor for memory protection.
2661 The available memory is mapped to fixed addresses using the memory
2662 controller. In this process, a contiguous block is formed for each
2663 memory type (Flash, SDRAM, SRAM), even when it consists of several
2664 physical memory banks.
2666 U-Boot is installed in the first 128 kB of the first Flash bank (on
2667 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2668 booting and sizing and initializing DRAM, the code relocates itself
2669 to the upper end of DRAM. Immediately below the U-Boot code some
2670 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
2671 configuration setting]. Below that, a structure with global Board
2672 Info data is placed, followed by the stack (growing downward).
2674 Additionally, some exception handler code is copied to the low 8 kB
2675 of DRAM (0x00000000 ... 0x00001FFF).
2677 So a typical memory configuration with 16 MB of DRAM could look like
2680 0x0000 0000 Exception Vector code
2683 0x0000 2000 Free for Application Use
2689 0x00FB FF20 Monitor Stack (Growing downward)
2690 0x00FB FFAC Board Info Data and permanent copy of global data
2691 0x00FC 0000 Malloc Arena
2694 0x00FE 0000 RAM Copy of Monitor Code
2695 ... eventually: LCD or video framebuffer
2696 ... eventually: pRAM (Protected RAM - unchanged by reset)
2697 0x00FF FFFF [End of RAM]
2700 System Initialization:
2701 ----------------------
2703 In the reset configuration, U-Boot starts at the reset entry point
2704 (on most PowerPC systens at address 0x00000100). Because of the reset
2705 configuration for CS0# this is a mirror of the onboard Flash memory.
2706 To be able to re-map memory U-Boot then jumps to it's link address.
2707 To be able to implement the initialization code in C, a (small!)
2708 initial stack is set up in the internal Dual Ported RAM (in case CPUs
2709 which provide such a feature like MPC8xx or MPC8260), or in a locked
2710 part of the data cache. After that, U-Boot initializes the CPU core,
2711 the caches and the SIU.
2713 Next, all (potentially) available memory banks are mapped using a
2714 preliminary mapping. For example, we put them on 512 MB boundaries
2715 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2716 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2717 programmed for SDRAM access. Using the temporary configuration, a
2718 simple memory test is run that determines the size of the SDRAM
2721 When there is more than one SDRAM bank, and the banks are of
2722 different size, the larger is mapped first. For equal size, the first
2723 bank (CS2#) is mapped first. The first mapping is always for address
2724 0x00000000, with any additional banks following immediately to create
2725 contiguous memory starting from 0.
2727 Then, the monitor installs itself at the upper end of the SDRAM area
2728 and allocates memory for use by malloc() and for the global Board
2729 Info data; also, the exception vector code is copied to the low RAM
2730 pages, and the final stack is set up.
2732 Only after this relocation will you have a "normal" C environment;
2733 until that you are restricted in several ways, mostly because you are
2734 running from ROM, and because the code will have to be relocated to a
2738 U-Boot Porting Guide:
2739 ----------------------
2741 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
2745 int main (int argc, char *argv[])
2747 sighandler_t no_more_time;
2749 signal (SIGALRM, no_more_time);
2750 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
2752 if (available_money > available_manpower) {
2753 pay consultant to port U-Boot;
2757 Download latest U-Boot source;
2759 Subscribe to u-boot-users mailing list;
2762 email ("Hi, I am new to U-Boot, how do I get started?");
2766 Read the README file in the top level directory;
2767 Read http://www.denx.de/re/DPLG.html
2768 Read the source, Luke;
2771 if (available_money > toLocalCurrency ($2500)) {
2774 Add a lot of aggravation and time;
2777 Create your own board support subdirectory;
2779 Create your own board config file;
2783 Add / modify source code;
2787 email ("Hi, I am having problems...");
2789 Send patch file to Wolfgang;
2794 void no_more_time (int sig)
2804 All contributions to U-Boot should conform to the Linux kernel
2805 coding style; see the file "Documentation/CodingStyle" in your Linux
2806 kernel source directory.
2808 Please note that U-Boot is implemented in C (and to some small parts
2809 in Assembler); no C++ is used, so please do not use C++ style
2810 comments (//) in your code.
2812 Submissions which do not conform to the standards may be returned
2813 with a request to reformat the changes.
2819 Since the number of patches for U-Boot is growing, we need to
2820 establish some rules. Submissions which do not conform to these rules
2821 may be rejected, even when they contain important and valuable stuff.
2824 When you send a patch, please include the following information with
2827 * For bug fixes: a description of the bug and how your patch fixes
2828 this bug. Please try to include a way of demonstrating that the
2829 patch actually fixes something.
2831 * For new features: a description of the feature and your
2834 * A CHANGELOG entry as plaintext (separate from the patch)
2836 * For major contributions, your entry to the CREDITS file
2838 * When you add support for a new board, don't forget to add this
2839 board to the MAKEALL script, too.
2841 * If your patch adds new configuration options, don't forget to
2842 document these in the README file.
2844 * The patch itself. If you are accessing the CVS repository use "cvs
2845 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
2846 version of diff does not support these options, then get the latest
2847 version of GNU diff.
2849 We accept patches as plain text, MIME attachments or as uuencoded
2854 * Before sending the patch, run the MAKEALL script on your patched
2855 source tree and make sure that no errors or warnings are reported
2856 for any of the boards.
2858 * Keep your modifications to the necessary minimum: A patch
2859 containing several unrelated changes or arbitrary reformats will be
2860 returned with a request to re-formatting / split it.
2862 * If you modify existing code, make sure that your new code does not
2863 add to the memory footprint of the code ;-) Small is beautiful!
2864 When adding new features, these should compile conditionally only
2865 (using #ifdef), and the resulting code with the new feature
2866 disabled must not need more memory than the old code without your
projects / platform / kernel / u-boot.git / blob