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wdenkc6097192002-11-03 00:24:07 +00001#
wdenk3a473b22004-01-03 00:43:19 +00002# (C) Copyright 2000 - 2004
wdenkc6097192002-11-03 00:24:07 +00003# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4#
5# See file CREDITS for list of people who contributed to this
6# project.
7#
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.
12#
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.
17#
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,
21# MA 02111-1307 USA
22#
23
24Summary:
25========
26
wdenk24ee89b2002-11-03 17:56:27 +000027This directory contains the source code for U-Boot, a boot loader for
28Embedded boards based on PowerPC and ARM processors, which can be
29installed in a boot ROM and used to initialize and test the hardware
30or to download and run application code.
wdenkc6097192002-11-03 00:24:07 +000031
32The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000033the source code originate in the Linux source tree, we have some
34header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000035support booting of Linux images.
36
37Some attention has been paid to make this software easily
38configurable and extendable. For instance, all monitor commands are
39implemented with the same call interface, so that it's very easy to
40add new commands. Also, instead of permanently adding rarely used
41code (for instance hardware test utilities) to the monitor, you can
42load and run it dynamically.
43
44
45Status:
46=======
47
48In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000049Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000050"working". In fact, many of them are used in production systems.
51
wdenk24ee89b2002-11-03 17:56:27 +000052In case of problems see the CHANGELOG and CREDITS files to find out
wdenkc6097192002-11-03 00:24:07 +000053who contributed the specific port.
54
wdenkc6097192002-11-03 00:24:07 +000055
56Where to get help:
57==================
58
wdenk24ee89b2002-11-03 17:56:27 +000059In case you have questions about, problems with or contributions for
60U-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
62previous traffic on the mailing list - please search the archive
wdenkc6097192002-11-03 00:24:07 +000063before asking FAQ's. Please see
64http://lists.sourceforge.net/lists/listinfo/u-boot-users/
65
66
67Where we come from:
68===================
69
70- start from 8xxrom sources
wdenk24ee89b2002-11-03 17:56:27 +000071- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000072- clean up code
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
77 * S-Record download
78 * network boot
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
wdenk24ee89b2002-11-03 17:56:27 +000080- create ARMBoot project (http://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000081- add other CPU families (starting with ARM)
wdenk24ee89b2002-11-03 17:56:27 +000082- create U-Boot project (http://sourceforge.net/projects/u-boot)
83
84
85Names and Spelling:
86===================
87
88The "official" name of this project is "Das U-Boot". The spelling
89"U-Boot" shall be used in all written text (documentation, comments
90in source files etc.). Example:
91
92 This is the README file for the U-Boot project.
93
94File names etc. shall be based on the string "u-boot". Examples:
95
96 include/asm-ppc/u-boot.h
97
98 #include <asm/u-boot.h>
99
100Variable names, preprocessor constants etc. shall be either based on
101the string "u_boot" or on "U_BOOT". Example:
102
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000105
106
wdenk93f19cc2002-12-17 17:55:09 +0000107Versioning:
108===========
109
110U-Boot uses a 3 level version number containing a version, a
111sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112sub-version "34", and patchlevel "4".
113
114The patchlevel is used to indicate certain stages of development
115between released versions, i. e. officially released versions of
116U-Boot will always have a patchlevel of "0".
117
118
wdenkc6097192002-11-03 00:24:07 +0000119Directory Hierarchy:
120====================
121
wdenk7152b1d2003-09-05 23:19:14 +0000122- board Board dependent files
123- common Misc architecture independent functions
wdenkc6097192002-11-03 00:24:07 +0000124- cpu CPU specific files
125- disk Code for disk drive partition handling
126- doc Documentation (don't expect too much)
wdenk7152b1d2003-09-05 23:19:14 +0000127- drivers Commonly used device drivers
wdenkc6097192002-11-03 00:24:07 +0000128- 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.
141
142- cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
wdenk2e5983d2003-07-15 20:04:06 +0000143- cpu/arm925t Files specific to ARM 925 CPUs
wdenk6f213472003-08-29 22:00:43 +0000144- cpu/arm926ejs Files specific to ARM 926 CPUs
wdenk0db5bca2003-03-31 17:27:09 +0000145- cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
wdenkc6097192002-11-03 00:24:07 +0000146- cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
147- cpu/mpc824x Files specific to Motorola MPC824x CPUs
148- cpu/mpc8260 Files specific to Motorola MPC8260 CPU
wdenk42d1f032003-10-15 23:53:47 +0000149- cpu/mpc85xx Files specific to Motorola MPC85xx CPUs
wdenkc6097192002-11-03 00:24:07 +0000150- cpu/ppc4xx Files specific to IBM 4xx CPUs
151
wdenk2e5983d2003-07-15 20:04:06 +0000152
wdenk3bac3512003-03-12 10:41:04 +0000153- board/LEOX/ Files specific to boards manufactured by The LEOX team
154- board/LEOX/elpt860 Files specific to ELPT860 boards
wdenkc6097192002-11-03 00:24:07 +0000155- board/RPXClassic
156 Files specific to RPXClassic boards
157- board/RPXlite Files specific to RPXlite boards
wdenk2abbe072003-06-16 23:50:08 +0000158- board/at91rm9200dk Files specific to AT91RM9200DK boards
wdenkc6097192002-11-03 00:24:07 +0000159- board/c2mon Files specific to c2mon boards
wdenk0db5bca2003-03-31 17:27:09 +0000160- board/cmi Files specific to cmi boards
wdenkc6097192002-11-03 00:24:07 +0000161- board/cogent Files specific to Cogent boards
162 (need further configuration)
163 Files specific to CPCIISER4 boards
164- board/cpu86 Files specific to CPU86 boards
165- board/cray/ Files specific to boards manufactured by Cray
166- board/cray/L1 Files specific to L1 boards
167- board/cu824 Files specific to CU824 boards
168- board/ebony Files specific to IBM Ebony board
169- board/eric Files specific to ERIC boards
170- board/esd/ Files specific to boards manufactured by ESD
171- board/esd/adciop Files specific to ADCIOP boards
172- board/esd/ar405 Files specific to AR405 boards
173- board/esd/canbt Files specific to CANBT boards
174- board/esd/cpci405 Files specific to CPCI405 boards
175- board/esd/cpciiser4 Files specific to CPCIISER4 boards
176- board/esd/common Common files for ESD boards
177- board/esd/dasa_sim Files specific to DASA_SIM boards
178- board/esd/du405 Files specific to DU405 boards
179- board/esd/ocrtc Files specific to OCRTC boards
180- board/esd/pci405 Files specific to PCI405 boards
181- board/esteem192e
182 Files specific to ESTEEM192E boards
183- board/etx094 Files specific to ETX_094 boards
184- board/evb64260
185 Files specific to EVB64260 boards
186- board/fads Files specific to FADS boards
187- board/flagadm Files specific to FLAGADM boards
wdenk7aa78612003-05-03 15:50:43 +0000188- board/gen860t Files specific to GEN860T and GEN860T_SC boards
wdenkc6097192002-11-03 00:24:07 +0000189- board/genietv Files specific to GENIETV boards
190- board/gth Files specific to GTH boards
191- board/hermes Files specific to HERMES boards
192- board/hymod Files specific to HYMOD boards
193- board/icu862 Files specific to ICU862 boards
194- board/ip860 Files specific to IP860 boards
195- board/iphase4539
196 Files specific to Interphase4539 boards
197- board/ivm Files specific to IVMS8/IVML24 boards
198- board/lantec Files specific to LANTEC boards
199- board/lwmon Files specific to LWMON boards
wdenk3a473b22004-01-03 00:43:19 +0000200- board/Marvell Files specific to Marvell development boards
201- board/Marvell/db64360 Files specific to db64360 board
202- board/Marvell/db64460 Files specific to db64460 board
wdenkc6097192002-11-03 00:24:07 +0000203- board/mbx8xx Files specific to MBX boards
204- board/mpc8260ads
wdenk180d3f72004-01-04 16:28:35 +0000205 Files specific to MPC826xADS and PQ2FADS-ZU/VR boards
wdenk42d1f032003-10-15 23:53:47 +0000206- board/mpc8540ads
207 Files specific to MPC8540ADS boards
208- board/mpc8560ads
209 Files specific to MPC8560ADS boards
wdenkc6097192002-11-03 00:24:07 +0000210- board/mpl/ Files specific to boards manufactured by MPL
211- board/mpl/common Common files for MPL boards
212- board/mpl/pip405 Files specific to PIP405 boards
213- board/mpl/mip405 Files specific to MIP405 boards
wdenk531716e2003-09-13 19:01:12 +0000214- board/mpl/vcma9 Files specific to VCMA9 boards
wdenkc6097192002-11-03 00:24:07 +0000215- board/musenki Files specific to MUSEKNI boards
216- board/mvs1 Files specific to MVS1 boards
217- board/nx823 Files specific to NX823 boards
218- board/oxc Files specific to OXC boards
wdenk945af8d2003-07-16 21:53:01 +0000219- board/omap1510inn
wdenk2e5983d2003-07-15 20:04:06 +0000220 Files specific to OMAP 1510 Innovator boards
wdenk42d1f032003-10-15 23:53:47 +0000221- board/omap1610inn
wdenk6f213472003-08-29 22:00:43 +0000222 Files specific to OMAP 1610 Innovator boards
wdenkc6097192002-11-03 00:24:07 +0000223- board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
224- board/pm826 Files specific to PM826 boards
225- board/ppmc8260
226 Files specific to PPMC8260 boards
wdenk3bbc8992003-12-07 22:27:15 +0000227- board/snmc/qs850 Files specific to QS850/823 boards
228- board/snmc/qs860t Files specific to QS860T boards
wdenkc6097192002-11-03 00:24:07 +0000229- board/rpxsuper
230 Files specific to RPXsuper boards
231- board/rsdproto
232 Files specific to RSDproto boards
233- board/sandpoint
234 Files specific to Sandpoint boards
235- board/sbc8260 Files specific to SBC8260 boards
236- board/sacsng Files specific to SACSng boards
237- board/siemens Files specific to boards manufactured by Siemens AG
238- board/siemens/CCM Files specific to CCM boards
239- board/siemens/IAD210 Files specific to IAD210 boards
240- board/siemens/SCM Files specific to SCM boards
241- board/siemens/pcu_e Files specific to PCU_E boards
242- board/sixnet Files specific to SIXNET boards
243- board/spd8xx Files specific to SPD8xxTS boards
244- board/tqm8260 Files specific to TQM8260 boards
245- board/tqm8xx Files specific to TQM8xxL boards
246- board/w7o Files specific to W7O boards
247- board/walnut405
248 Files specific to Walnut405 boards
249- board/westel/ Files specific to boards manufactured by Westel Wireless
250- board/westel/amx860 Files specific to AMX860 boards
251- board/utx8245 Files specific to UTX8245 boards
wdenk54387ac2003-10-08 22:45:44 +0000252- board/zpc1900 Files specific to Zephyr Engineering ZPC.1900 board
wdenkc6097192002-11-03 00:24:07 +0000253
254Software Configuration:
255=======================
256
257Configuration is usually done using C preprocessor defines; the
258rationale behind that is to avoid dead code whenever possible.
259
260There are two classes of configuration variables:
261
262* Configuration _OPTIONS_:
263 These are selectable by the user and have names beginning with
264 "CONFIG_".
265
266* Configuration _SETTINGS_:
267 These depend on the hardware etc. and should not be meddled with if
268 you don't know what you're doing; they have names beginning with
269 "CFG_".
270
271Later we will add a configuration tool - probably similar to or even
272identical to what's used for the Linux kernel. Right now, we have to
273do the configuration by hand, which means creating some symbolic
274links and editing some configuration files. We use the TQM8xxL boards
275as an example here.
276
277
278Selection of Processor Architecture and Board Type:
279---------------------------------------------------
280
281For all supported boards there are ready-to-use default
282configurations available; just type "make <board_name>_config".
283
284Example: For a TQM823L module type:
285
286 cd u-boot
287 make TQM823L_config
288
289For the Cogent platform, you need to specify the cpu type as well;
290e.g. "make cogent_mpc8xx_config". And also configure the cogent
291directory according to the instructions in cogent/README.
292
293
294Configuration Options:
295----------------------
296
297Configuration depends on the combination of board and CPU type; all
298such information is kept in a configuration file
299"include/configs/<board_name>.h".
300
301Example: For a TQM823L module, all configuration settings are in
302"include/configs/TQM823L.h".
303
304
wdenk7f6c2cb2002-11-10 22:06:23 +0000305Many of the options are named exactly as the corresponding Linux
306kernel configuration options. The intention is to make it easier to
307build a config tool - later.
308
309
wdenkc6097192002-11-03 00:24:07 +0000310The following options need to be configured:
311
312- CPU Type: Define exactly one of
313
314 PowerPC based CPUs:
315 -------------------
316 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
wdenk0db5bca2003-03-31 17:27:09 +0000317 or CONFIG_MPC5xx
wdenkc6097192002-11-03 00:24:07 +0000318 or CONFIG_MPC824X, CONFIG_MPC8260
wdenk42d1f032003-10-15 23:53:47 +0000319 or CONFIG_MPC85xx
wdenkc6097192002-11-03 00:24:07 +0000320 or CONFIG_IOP480
321 or CONFIG_405GP
wdenk12f34242003-09-02 22:48:03 +0000322 or CONFIG_405EP
wdenkc6097192002-11-03 00:24:07 +0000323 or CONFIG_440
324 or CONFIG_MPC74xx
wdenk72755c72003-06-20 23:10:58 +0000325 or CONFIG_750FX
wdenkc6097192002-11-03 00:24:07 +0000326
327 ARM based CPUs:
328 ---------------
329 CONFIG_SA1110
330 CONFIG_ARM7
331 CONFIG_PXA250
332
333
334- Board Type: Define exactly one of
335
336 PowerPC based boards:
337 ---------------------
338
339 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
340 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
341 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
342 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
343 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
344 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
345 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
346 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
347 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
348 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
349 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
350 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
351 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
352 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
353 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
354 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
355 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
356 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
357 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
358 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
359 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
360 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
361 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
362 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
363 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
364 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
365 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
366 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
367 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
wdenk608c9142003-01-13 23:54:46 +0000368 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
wdenk7f70e852003-05-20 14:25:27 +0000369 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
wdenk42d1f032003-10-15 23:53:47 +0000370 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900,
wdenk3a473b22004-01-03 00:43:19 +0000371 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850,
372 CONFIG_QS823, CONFIG_QS860T, CONFIG_DB64360,
wdenk180d3f72004-01-04 16:28:35 +0000373 CONFIG_DB64460, CONFIG_DUET_ADS
wdenkc6097192002-11-03 00:24:07 +0000374
375 ARM based boards:
376 -----------------
377
378 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
379 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
wdenk6f213472003-08-29 22:00:43 +0000380 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610
wdenkc6097192002-11-03 00:24:07 +0000381 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
wdenk531716e2003-09-13 19:01:12 +0000382 CONFIG_TRAB, CONFIG_VCMA9, CONFIG_AT91RM9200DK
wdenkc6097192002-11-03 00:24:07 +0000383
384
385- CPU Module Type: (if CONFIG_COGENT is defined)
386 Define exactly one of
387 CONFIG_CMA286_60_OLD
388--- FIXME --- not tested yet:
389 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
390 CONFIG_CMA287_23, CONFIG_CMA287_50
391
392- Motherboard Type: (if CONFIG_COGENT is defined)
393 Define exactly one of
394 CONFIG_CMA101, CONFIG_CMA102
395
396- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
397 Define one or more of
398 CONFIG_CMA302
399
400- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
401 Define one or more of
402 CONFIG_LCD_HEARTBEAT - update a character position on
403 the lcd display every second with
404 a "rotator" |\-/|\-/
405
wdenk2535d602003-07-17 23:16:40 +0000406- Board flavour: (if CONFIG_MPC8260ADS is defined)
407 CONFIG_ADSTYPE
408 Possible values are:
409 CFG_8260ADS - original MPC8260ADS
wdenk180d3f72004-01-04 16:28:35 +0000410 CFG_8266ADS - MPC8266ADS
wdenk54387ac2003-10-08 22:45:44 +0000411 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
wdenk2535d602003-07-17 23:16:40 +0000412
413
wdenkc6097192002-11-03 00:24:07 +0000414- MPC824X Family Member (if CONFIG_MPC824X is defined)
wdenk5da627a2003-10-09 20:09:04 +0000415 Define exactly one of
416 CONFIG_MPC8240, CONFIG_MPC8245
wdenkc6097192002-11-03 00:24:07 +0000417
wdenk75d1ea72004-01-31 20:06:54 +0000418- 8xx CPU Options: (if using an MPC8xx cpu)
wdenkc6097192002-11-03 00:24:07 +0000419 Define one or more of
wdenk5da627a2003-10-09 20:09:04 +0000420 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
421 e.g. if there is no 32KHz
422 reference PIT/RTC clock
wdenkc6097192002-11-03 00:24:07 +0000423
wdenk75d1ea72004-01-31 20:06:54 +0000424- 859/866 CPU options: (if using a MPC859 or MPC866 CPU):
425 CFG_866_OSCCLK
426 CFG_866_CPUCLK_MIN
427 CFG_866_CPUCLK_MAX
428 CFG_866_CPUCLK_DEFAULT
429 See doc/README.MPC866
430
431 CFG_MEASURE_CPUCLK
432
433 Define this to measure the actual CPU clock instead
434 of relying on the correctness of the configured
435 values. Mostly useful for board bringup to make sure
436 the PLL is locked at the intended frequency. Note
437 that this requires a (stable) reference clock (32 kHz
438 RTC clock),
439
wdenk5da627a2003-10-09 20:09:04 +0000440- Linux Kernel Interface:
wdenkc6097192002-11-03 00:24:07 +0000441 CONFIG_CLOCKS_IN_MHZ
442
443 U-Boot stores all clock information in Hz
444 internally. For binary compatibility with older Linux
445 kernels (which expect the clocks passed in the
446 bd_info data to be in MHz) the environment variable
447 "clocks_in_mhz" can be defined so that U-Boot
448 converts clock data to MHZ before passing it to the
449 Linux kernel.
wdenkc6097192002-11-03 00:24:07 +0000450 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
451 "clocks_in_mhz=1" is automatically included in the
452 default environment.
453
wdenk5da627a2003-10-09 20:09:04 +0000454 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
455
456 When transfering memsize parameter to linux, some versions
457 expect it to be in bytes, others in MB.
458 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
459
wdenkc6097192002-11-03 00:24:07 +0000460- Console Interface:
wdenk43d96162003-03-06 00:02:04 +0000461 Depending on board, define exactly one serial port
462 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
463 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
464 console by defining CONFIG_8xx_CONS_NONE
wdenkc6097192002-11-03 00:24:07 +0000465
466 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
467 port routines must be defined elsewhere
468 (i.e. serial_init(), serial_getc(), ...)
469
470 CONFIG_CFB_CONSOLE
471 Enables console device for a color framebuffer. Needs following
472 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
473 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
474 (default big endian)
475 VIDEO_HW_RECTFILL graphic chip supports
476 rectangle fill
477 (cf. smiLynxEM)
478 VIDEO_HW_BITBLT graphic chip supports
479 bit-blit (cf. smiLynxEM)
480 VIDEO_VISIBLE_COLS visible pixel columns
481 (cols=pitch)
482 VIDEO_VISIBLE_ROWS visible pixel rows
483 VIDEO_PIXEL_SIZE bytes per pixel
484 VIDEO_DATA_FORMAT graphic data format
485 (0-5, cf. cfb_console.c)
486 VIDEO_FB_ADRS framebuffer address
487 VIDEO_KBD_INIT_FCT keyboard int fct
488 (i.e. i8042_kbd_init())
489 VIDEO_TSTC_FCT test char fct
490 (i.e. i8042_tstc)
491 VIDEO_GETC_FCT get char fct
492 (i.e. i8042_getc)
493 CONFIG_CONSOLE_CURSOR cursor drawing on/off
494 (requires blink timer
495 cf. i8042.c)
496 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
497 CONFIG_CONSOLE_TIME display time/date info in
498 upper right corner
499 (requires CFG_CMD_DATE)
500 CONFIG_VIDEO_LOGO display Linux logo in
501 upper left corner
wdenka6c7ad22002-12-03 21:28:10 +0000502 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
503 linux_logo.h for logo.
504 Requires CONFIG_VIDEO_LOGO
wdenkc6097192002-11-03 00:24:07 +0000505 CONFIG_CONSOLE_EXTRA_INFO
506 addional board info beside
507 the logo
508
wdenk43d96162003-03-06 00:02:04 +0000509 When CONFIG_CFB_CONSOLE is defined, video console is
510 default i/o. Serial console can be forced with
511 environment 'console=serial'.
wdenkc6097192002-11-03 00:24:07 +0000512
wdenkd4ca31c2004-01-02 14:00:00 +0000513 When CONFIG_SILENT_CONSOLE is defined, all console
514 messages (by U-Boot and Linux!) can be silenced with
515 the "silent" environment variable. See
516 doc/README.silent for more information.
wdenka3ad8e22003-10-19 23:22:11 +0000517
wdenkc6097192002-11-03 00:24:07 +0000518- Console Baudrate:
519 CONFIG_BAUDRATE - in bps
520 Select one of the baudrates listed in
521 CFG_BAUDRATE_TABLE, see below.
wdenk3bbc8992003-12-07 22:27:15 +0000522 CFG_BRGCLK_PRESCALE, baudrate prescale
wdenkc6097192002-11-03 00:24:07 +0000523
524- Interrupt driven serial port input:
525 CONFIG_SERIAL_SOFTWARE_FIFO
526
527 PPC405GP only.
528 Use an interrupt handler for receiving data on the
529 serial port. It also enables using hardware handshake
530 (RTS/CTS) and UART's built-in FIFO. Set the number of
531 bytes the interrupt driven input buffer should have.
532
533 Set to 0 to disable this feature (this is the default).
534 This will also disable hardware handshake.
535
stroese1d49b1f2003-05-23 11:39:05 +0000536- Console UART Number:
537 CONFIG_UART1_CONSOLE
538
539 IBM PPC4xx only.
540 If defined internal UART1 (and not UART0) is used
541 as default U-Boot console.
542
wdenkc6097192002-11-03 00:24:07 +0000543- Boot Delay: CONFIG_BOOTDELAY - in seconds
544 Delay before automatically booting the default image;
545 set to -1 to disable autoboot.
546
547 See doc/README.autoboot for these options that
548 work with CONFIG_BOOTDELAY. None are required.
549 CONFIG_BOOT_RETRY_TIME
550 CONFIG_BOOT_RETRY_MIN
551 CONFIG_AUTOBOOT_KEYED
552 CONFIG_AUTOBOOT_PROMPT
553 CONFIG_AUTOBOOT_DELAY_STR
554 CONFIG_AUTOBOOT_STOP_STR
555 CONFIG_AUTOBOOT_DELAY_STR2
556 CONFIG_AUTOBOOT_STOP_STR2
557 CONFIG_ZERO_BOOTDELAY_CHECK
558 CONFIG_RESET_TO_RETRY
559
560- Autoboot Command:
561 CONFIG_BOOTCOMMAND
562 Only needed when CONFIG_BOOTDELAY is enabled;
563 define a command string that is automatically executed
564 when no character is read on the console interface
565 within "Boot Delay" after reset.
566
567 CONFIG_BOOTARGS
wdenk43d96162003-03-06 00:02:04 +0000568 This can be used to pass arguments to the bootm
569 command. The value of CONFIG_BOOTARGS goes into the
570 environment value "bootargs".
wdenkc6097192002-11-03 00:24:07 +0000571
572 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk43d96162003-03-06 00:02:04 +0000573 The value of these goes into the environment as
574 "ramboot" and "nfsboot" respectively, and can be used
575 as a convenience, when switching between booting from
576 ram and nfs.
wdenkc6097192002-11-03 00:24:07 +0000577
578- Pre-Boot Commands:
579 CONFIG_PREBOOT
580
581 When this option is #defined, the existence of the
582 environment variable "preboot" will be checked
583 immediately before starting the CONFIG_BOOTDELAY
584 countdown and/or running the auto-boot command resp.
585 entering interactive mode.
586
587 This feature is especially useful when "preboot" is
588 automatically generated or modified. For an example
589 see the LWMON board specific code: here "preboot" is
590 modified when the user holds down a certain
591 combination of keys on the (special) keyboard when
592 booting the systems
593
594- Serial Download Echo Mode:
595 CONFIG_LOADS_ECHO
596 If defined to 1, all characters received during a
597 serial download (using the "loads" command) are
598 echoed back. This might be needed by some terminal
599 emulations (like "cu"), but may as well just take
600 time on others. This setting #define's the initial
601 value of the "loads_echo" environment variable.
602
603- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
604 CONFIG_KGDB_BAUDRATE
605 Select one of the baudrates listed in
606 CFG_BAUDRATE_TABLE, see below.
607
608- Monitor Functions:
609 CONFIG_COMMANDS
610 Most monitor functions can be selected (or
611 de-selected) by adjusting the definition of
612 CONFIG_COMMANDS; to select individual functions,
613 #define CONFIG_COMMANDS by "OR"ing any of the
614 following values:
615
616 #define enables commands:
617 -------------------------
618 CFG_CMD_ASKENV * ask for env variable
wdenk78137c32003-09-15 18:00:00 +0000619 CFG_CMD_AUTOSCRIPT Autoscript Support
wdenkc6097192002-11-03 00:24:07 +0000620 CFG_CMD_BDI bdinfo
621 CFG_CMD_BEDBUG Include BedBug Debugger
wdenk78137c32003-09-15 18:00:00 +0000622 CFG_CMD_BMP * BMP support
wdenkc6097192002-11-03 00:24:07 +0000623 CFG_CMD_BOOTD bootd
624 CFG_CMD_CACHE icache, dcache
625 CFG_CMD_CONSOLE coninfo
626 CFG_CMD_DATE * support for RTC, date/time...
627 CFG_CMD_DHCP DHCP support
wdenk78137c32003-09-15 18:00:00 +0000628 CFG_CMD_DIAG * Diagnostics
629 CFG_CMD_DOC * Disk-On-Chip Support
wdenk42d1f032003-10-15 23:53:47 +0000630 CFG_CMD_DTT Digital Therm and Thermostat
wdenkc6097192002-11-03 00:24:07 +0000631 CFG_CMD_ECHO * echo arguments
632 CFG_CMD_EEPROM * EEPROM read/write support
633 CFG_CMD_ELF bootelf, bootvx
634 CFG_CMD_ENV saveenv
635 CFG_CMD_FDC * Floppy Disk Support
wdenk71f95112003-06-15 22:40:42 +0000636 CFG_CMD_FAT FAT partition support
wdenk2262cfe2002-11-18 00:14:45 +0000637 CFG_CMD_FDOS * Dos diskette Support
wdenkc6097192002-11-03 00:24:07 +0000638 CFG_CMD_FLASH flinfo, erase, protect
639 CFG_CMD_FPGA FPGA device initialization support
wdenk78137c32003-09-15 18:00:00 +0000640 CFG_CMD_HWFLOW * RTS/CTS hw flow control
wdenkc6097192002-11-03 00:24:07 +0000641 CFG_CMD_I2C * I2C serial bus support
642 CFG_CMD_IDE * IDE harddisk support
643 CFG_CMD_IMI iminfo
wdenk78137c32003-09-15 18:00:00 +0000644 CFG_CMD_IMLS List all found images
wdenkc6097192002-11-03 00:24:07 +0000645 CFG_CMD_IMMAP * IMMR dump support
646 CFG_CMD_IRQ * irqinfo
wdenk78137c32003-09-15 18:00:00 +0000647 CFG_CMD_JFFS2 * JFFS2 Support
wdenkc6097192002-11-03 00:24:07 +0000648 CFG_CMD_KGDB * kgdb
649 CFG_CMD_LOADB loadb
650 CFG_CMD_LOADS loads
651 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
652 loop, mtest
wdenk78137c32003-09-15 18:00:00 +0000653 CFG_CMD_MISC Misc functions like sleep etc
wdenk71f95112003-06-15 22:40:42 +0000654 CFG_CMD_MMC MMC memory mapped support
wdenkc6097192002-11-03 00:24:07 +0000655 CFG_CMD_MII MII utility commands
wdenk78137c32003-09-15 18:00:00 +0000656 CFG_CMD_NAND * NAND support
wdenkc6097192002-11-03 00:24:07 +0000657 CFG_CMD_NET bootp, tftpboot, rarpboot
658 CFG_CMD_PCI * pciinfo
659 CFG_CMD_PCMCIA * PCMCIA support
wdenk78137c32003-09-15 18:00:00 +0000660 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
wdenkef5a9672003-12-07 00:46:27 +0000661 CFG_CMD_PORTIO * Port I/O
wdenkc6097192002-11-03 00:24:07 +0000662 CFG_CMD_REGINFO * Register dump
663 CFG_CMD_RUN run command in env variable
wdenk78137c32003-09-15 18:00:00 +0000664 CFG_CMD_SAVES save S record dump
wdenkc6097192002-11-03 00:24:07 +0000665 CFG_CMD_SCSI * SCSI Support
wdenk78137c32003-09-15 18:00:00 +0000666 CFG_CMD_SDRAM * print SDRAM configuration information
wdenkc6097192002-11-03 00:24:07 +0000667 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
668 CFG_CMD_SPI * SPI serial bus support
669 CFG_CMD_USB * USB support
wdenk78137c32003-09-15 18:00:00 +0000670 CFG_CMD_VFD * VFD support (TRAB)
wdenkc6097192002-11-03 00:24:07 +0000671 CFG_CMD_BSP * Board SPecific functions
672 -----------------------------------------------
673 CFG_CMD_ALL all
674
675 CFG_CMD_DFL Default configuration; at the moment
676 this is includes all commands, except
677 the ones marked with "*" in the list
678 above.
679
680 If you don't define CONFIG_COMMANDS it defaults to
681 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
682 override the default settings in the respective
683 include file.
684
685 EXAMPLE: If you want all functions except of network
686 support you can write:
687
688 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
689
690
691 Note: Don't enable the "icache" and "dcache" commands
wdenk43d96162003-03-06 00:02:04 +0000692 (configuration option CFG_CMD_CACHE) unless you know
693 what you (and your U-Boot users) are doing. Data
694 cache cannot be enabled on systems like the 8xx or
695 8260 (where accesses to the IMMR region must be
696 uncached), and it cannot be disabled on all other
697 systems where we (mis-) use the data cache to hold an
698 initial stack and some data.
wdenkc6097192002-11-03 00:24:07 +0000699
700
701 XXX - this list needs to get updated!
702
703- Watchdog:
704 CONFIG_WATCHDOG
705 If this variable is defined, it enables watchdog
wdenk7152b1d2003-09-05 23:19:14 +0000706 support. There must be support in the platform specific
wdenkc6097192002-11-03 00:24:07 +0000707 code for a watchdog. For the 8xx and 8260 CPUs, the
708 SIU Watchdog feature is enabled in the SYPCR
709 register.
710
stroesec1551ea2003-04-04 15:53:41 +0000711- U-Boot Version:
712 CONFIG_VERSION_VARIABLE
713 If this variable is defined, an environment variable
714 named "ver" is created by U-Boot showing the U-Boot
715 version as printed by the "version" command.
716 This variable is readonly.
717
wdenkc6097192002-11-03 00:24:07 +0000718- Real-Time Clock:
719
720 When CFG_CMD_DATE is selected, the type of the RTC
721 has to be selected, too. Define exactly one of the
722 following options:
723
724 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
725 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
726 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000727 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000728 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000729 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
wdenk3bac3512003-03-12 10:41:04 +0000730 CONFIG_RTC_DS164x - use Dallas DS164x RTC
wdenkc6097192002-11-03 00:24:07 +0000731
wdenkb37c7e52003-06-30 16:24:52 +0000732 Note that if the RTC uses I2C, then the I2C interface
733 must also be configured. See I2C Support, below.
734
wdenkc6097192002-11-03 00:24:07 +0000735- Timestamp Support:
736
wdenk43d96162003-03-06 00:02:04 +0000737 When CONFIG_TIMESTAMP is selected, the timestamp
738 (date and time) of an image is printed by image
739 commands like bootm or iminfo. This option is
740 automatically enabled when you select CFG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000741
742- Partition Support:
743 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
744 and/or CONFIG_ISO_PARTITION
745
746 If IDE or SCSI support is enabled (CFG_CMD_IDE or
747 CFG_CMD_SCSI) you must configure support for at least
748 one partition type as well.
749
750- IDE Reset method:
751 CONFIG_IDE_RESET_ROUTINE
752
753 Set this to define that instead of a reset Pin, the
754 routine ide_set_reset(int idereset) will be used.
755
756- ATAPI Support:
757 CONFIG_ATAPI
758
759 Set this to enable ATAPI support.
760
761- SCSI Support:
762 At the moment only there is only support for the
763 SYM53C8XX SCSI controller; define
764 CONFIG_SCSI_SYM53C8XX to enable it.
765
766 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
767 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
768 CFG_SCSI_MAX_LUN] can be adjusted to define the
769 maximum numbers of LUNs, SCSI ID's and target
770 devices.
771 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
772
773- NETWORK Support (PCI):
wdenk682011f2003-06-03 23:54:09 +0000774 CONFIG_E1000
775 Support for Intel 8254x gigabit chips.
stroese53cf9432003-06-05 15:39:44 +0000776
wdenkc6097192002-11-03 00:24:07 +0000777 CONFIG_EEPRO100
778 Support for Intel 82557/82559/82559ER chips.
779 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
780 write routine for first time initialisation.
781
782 CONFIG_TULIP
783 Support for Digital 2114x chips.
784 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
785 modem chip initialisation (KS8761/QS6611).
786
787 CONFIG_NATSEMI
788 Support for National dp83815 chips.
789
790 CONFIG_NS8382X
791 Support for National dp8382[01] gigabit chips.
792
wdenk45219c42003-05-12 21:50:16 +0000793- NETWORK Support (other):
794
795 CONFIG_DRIVER_LAN91C96
796 Support for SMSC's LAN91C96 chips.
797
798 CONFIG_LAN91C96_BASE
799 Define this to hold the physical address
800 of the LAN91C96's I/O space
801
802 CONFIG_LAN91C96_USE_32_BIT
803 Define this to enable 32 bit addressing
804
wdenkc6097192002-11-03 00:24:07 +0000805- USB Support:
806 At the moment only the UHCI host controller is
807 supported (PIP405, MIP405); define
808 CONFIG_USB_UHCI to enable it.
809 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
810 end define CONFIG_USB_STORAGE to enable the USB
811 storage devices.
812 Note:
813 Supported are USB Keyboards and USB Floppy drives
814 (TEAC FD-05PUB).
815
wdenk71f95112003-06-15 22:40:42 +0000816- MMC Support:
wdenk8bde7f72003-06-27 21:31:46 +0000817 The MMC controller on the Intel PXA is supported. To
818 enable this define CONFIG_MMC. The MMC can be
819 accessed from the boot prompt by mapping the device
wdenk71f95112003-06-15 22:40:42 +0000820 to physical memory similar to flash. Command line is
821 enabled with CFG_CMD_MMC. The MMC driver also works with
wdenk8bde7f72003-06-27 21:31:46 +0000822 the FAT fs. This is enabled with CFG_CMD_FAT.
wdenk71f95112003-06-15 22:40:42 +0000823
wdenkc6097192002-11-03 00:24:07 +0000824- Keyboard Support:
825 CONFIG_ISA_KEYBOARD
826
827 Define this to enable standard (PC-Style) keyboard
828 support
829
830 CONFIG_I8042_KBD
831 Standard PC keyboard driver with US (is default) and
832 GERMAN key layout (switch via environment 'keymap=de') support.
833 Export function i8042_kbd_init, i8042_tstc and i8042_getc
834 for cfb_console. Supports cursor blinking.
835
836- Video support:
837 CONFIG_VIDEO
838
839 Define this to enable video support (for output to
840 video).
841
842 CONFIG_VIDEO_CT69000
843
844 Enable Chips & Technologies 69000 Video chip
845
846 CONFIG_VIDEO_SMI_LYNXEM
847 Enable Silicon Motion SMI 712/710/810 Video chip
848 Videomode are selected via environment 'videomode' with
849 standard LiLo mode numbers.
850 Following modes are supported (* is default):
851
wdenk43d96162003-03-06 00:02:04 +0000852 800x600 1024x768 1280x1024
853 256 (8bit) 303* 305 307
854 65536 (16bit) 314 317 31a
855 16,7 Mill (24bit) 315 318 31b
wdenkc6097192002-11-03 00:24:07 +0000856 (i.e. setenv videomode 317; saveenv; reset;)
857
stroesec1551ea2003-04-04 15:53:41 +0000858 CONFIG_VIDEO_SED13806
wdenk43d96162003-03-06 00:02:04 +0000859 Enable Epson SED13806 driver. This driver supports 8bpp
wdenka6c7ad22002-12-03 21:28:10 +0000860 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
861 or CONFIG_VIDEO_SED13806_16BPP
862
wdenk682011f2003-06-03 23:54:09 +0000863- Keyboard Support:
wdenk8bde7f72003-06-27 21:31:46 +0000864 CONFIG_KEYBOARD
wdenk682011f2003-06-03 23:54:09 +0000865
wdenk8bde7f72003-06-27 21:31:46 +0000866 Define this to enable a custom keyboard support.
867 This simply calls drv_keyboard_init() which must be
868 defined in your board-specific files.
869 The only board using this so far is RBC823.
wdenka6c7ad22002-12-03 21:28:10 +0000870
wdenkc6097192002-11-03 00:24:07 +0000871- LCD Support: CONFIG_LCD
872
873 Define this to enable LCD support (for output to LCD
874 display); also select one of the supported displays
875 by defining one of these:
876
wdenkfd3103b2003-11-25 16:55:19 +0000877 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +0000878
wdenkfd3103b2003-11-25 16:55:19 +0000879 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +0000880
wdenkfd3103b2003-11-25 16:55:19 +0000881 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +0000882
wdenkfd3103b2003-11-25 16:55:19 +0000883 NEC NL6448BC20-08. 6.5", 640x480.
884 Active, color, single scan.
885
886 CONFIG_NEC_NL6448BC33_54
887
888 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +0000889 Active, color, single scan.
890
891 CONFIG_SHARP_16x9
892
893 Sharp 320x240. Active, color, single scan.
894 It isn't 16x9, and I am not sure what it is.
895
896 CONFIG_SHARP_LQ64D341
897
898 Sharp LQ64D341 display, 640x480.
899 Active, color, single scan.
900
901 CONFIG_HLD1045
902
903 HLD1045 display, 640x480.
904 Active, color, single scan.
905
906 CONFIG_OPTREX_BW
907
908 Optrex CBL50840-2 NF-FW 99 22 M5
909 or
910 Hitachi LMG6912RPFC-00T
911 or
912 Hitachi SP14Q002
913
914 320x240. Black & white.
915
916 Normally display is black on white background; define
917 CFG_WHITE_ON_BLACK to get it inverted.
918
wdenk7152b1d2003-09-05 23:19:14 +0000919- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenkd791b1d2003-04-20 14:04:18 +0000920
wdenk8bde7f72003-06-27 21:31:46 +0000921 If this option is set, the environment is checked for
922 a variable "splashimage". If found, the usual display
923 of logo, copyright and system information on the LCD
924 is supressed and the BMP image at the address
925 specified in "splashimage" is loaded instead. The
926 console is redirected to the "nulldev", too. This
927 allows for a "silent" boot where a splash screen is
928 loaded very quickly after power-on.
wdenkd791b1d2003-04-20 14:04:18 +0000929
wdenkc29fdfc2003-08-29 20:57:53 +0000930- Compression support:
931 CONFIG_BZIP2
932
933 If this option is set, support for bzip2 compressed
934 images is included. If not, only uncompressed and gzip
935 compressed images are supported.
936
wdenk42d1f032003-10-15 23:53:47 +0000937 NOTE: the bzip2 algorithm requires a lot of RAM, so
938 the malloc area (as defined by CFG_MALLOC_LEN) should
939 be at least 4MB.
wdenkd791b1d2003-04-20 14:04:18 +0000940
wdenkc6097192002-11-03 00:24:07 +0000941- Ethernet address:
942 CONFIG_ETHADDR
943 CONFIG_ETH2ADDR
944 CONFIG_ETH3ADDR
945
946 Define a default value for ethernet address to use
947 for the respective ethernet interface, in case this
948 is not determined automatically.
949
950- IP address:
951 CONFIG_IPADDR
952
953 Define a default value for the IP address to use for
954 the default ethernet interface, in case this is not
955 determined through e.g. bootp.
956
957- Server IP address:
958 CONFIG_SERVERIP
959
960 Defines a default value for theIP address of a TFTP
961 server to contact when using the "tftboot" command.
962
963- BOOTP Recovery Mode:
964 CONFIG_BOOTP_RANDOM_DELAY
965
966 If you have many targets in a network that try to
967 boot using BOOTP, you may want to avoid that all
968 systems send out BOOTP requests at precisely the same
969 moment (which would happen for instance at recovery
970 from a power failure, when all systems will try to
971 boot, thus flooding the BOOTP server. Defining
972 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
973 inserted before sending out BOOTP requests. The
974 following delays are insterted then:
975
976 1st BOOTP request: delay 0 ... 1 sec
977 2nd BOOTP request: delay 0 ... 2 sec
978 3rd BOOTP request: delay 0 ... 4 sec
979 4th and following
980 BOOTP requests: delay 0 ... 8 sec
981
stroesefe389a82003-08-28 14:17:32 +0000982- DHCP Advanced Options:
983 CONFIG_BOOTP_MASK
984
985 You can fine tune the DHCP functionality by adding
986 these flags to the CONFIG_BOOTP_MASK define:
987
988 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
989 serverip from a DHCP server, it is possible that more
990 than one DNS serverip is offered to the client.
991 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
992 serverip will be stored in the additional environment
993 variable "dnsip2". The first DNS serverip is always
994 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
995 is added to the CONFIG_BOOTP_MASK.
996
997 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
998 to do a dynamic update of a DNS server. To do this, they
999 need the hostname of the DHCP requester.
1000 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1001 CONFIG_BOOTP_MASK, the content of the "hostname"
1002 environment variable is passed as option 12 to
1003 the DHCP server.
1004
wdenkc6097192002-11-03 00:24:07 +00001005- Status LED: CONFIG_STATUS_LED
1006
1007 Several configurations allow to display the current
1008 status using a LED. For instance, the LED will blink
1009 fast while running U-Boot code, stop blinking as
1010 soon as a reply to a BOOTP request was received, and
1011 start blinking slow once the Linux kernel is running
1012 (supported by a status LED driver in the Linux
1013 kernel). Defining CONFIG_STATUS_LED enables this
1014 feature in U-Boot.
1015
1016- CAN Support: CONFIG_CAN_DRIVER
1017
1018 Defining CONFIG_CAN_DRIVER enables CAN driver support
1019 on those systems that support this (optional)
1020 feature, like the TQM8xxL modules.
1021
1022- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1023
wdenkb37c7e52003-06-30 16:24:52 +00001024 These enable I2C serial bus commands. Defining either of
wdenk945af8d2003-07-16 21:53:01 +00001025 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1026 include the appropriate I2C driver for the selected cpu.
wdenkc6097192002-11-03 00:24:07 +00001027
wdenk945af8d2003-07-16 21:53:01 +00001028 This will allow you to use i2c commands at the u-boot
1029 command line (as long as you set CFG_CMD_I2C in
wdenkb37c7e52003-06-30 16:24:52 +00001030 CONFIG_COMMANDS) and communicate with i2c based realtime
1031 clock chips. See common/cmd_i2c.c for a description of the
wdenk43d96162003-03-06 00:02:04 +00001032 command line interface.
wdenkc6097192002-11-03 00:24:07 +00001033
wdenk945af8d2003-07-16 21:53:01 +00001034 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
wdenkc6097192002-11-03 00:24:07 +00001035
wdenk945af8d2003-07-16 21:53:01 +00001036 CONFIG_SOFT_I2C configures u-boot to use a software (aka
wdenkb37c7e52003-06-30 16:24:52 +00001037 bit-banging) driver instead of CPM or similar hardware
1038 support for I2C.
wdenkc6097192002-11-03 00:24:07 +00001039
wdenk945af8d2003-07-16 21:53:01 +00001040 There are several other quantities that must also be
wdenkb37c7e52003-06-30 16:24:52 +00001041 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
wdenkc6097192002-11-03 00:24:07 +00001042
wdenkb37c7e52003-06-30 16:24:52 +00001043 In both cases you will need to define CFG_I2C_SPEED
wdenk945af8d2003-07-16 21:53:01 +00001044 to be the frequency (in Hz) at which you wish your i2c bus
1045 to run and CFG_I2C_SLAVE to be the address of this node (ie
1046 the cpu's i2c node address).
1047
wdenkb37c7e52003-06-30 16:24:52 +00001048 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1049 sets the cpu up as a master node and so its address should
1050 therefore be cleared to 0 (See, eg, MPC823e User's Manual
wdenk945af8d2003-07-16 21:53:01 +00001051 p.16-473). So, set CFG_I2C_SLAVE to 0.
wdenkc6097192002-11-03 00:24:07 +00001052
wdenk945af8d2003-07-16 21:53:01 +00001053 That's all that's required for CONFIG_HARD_I2C.
wdenkb37c7e52003-06-30 16:24:52 +00001054
1055 If you use the software i2c interface (CONFIG_SOFT_I2C)
1056 then the following macros need to be defined (examples are
1057 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001058
1059 I2C_INIT
1060
wdenkb37c7e52003-06-30 16:24:52 +00001061 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001062 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001063
wdenkb37c7e52003-06-30 16:24:52 +00001064 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1065
wdenkc6097192002-11-03 00:24:07 +00001066 I2C_PORT
1067
wdenk43d96162003-03-06 00:02:04 +00001068 (Only for MPC8260 CPU). The I/O port to use (the code
1069 assumes both bits are on the same port). Valid values
1070 are 0..3 for ports A..D.
wdenkc6097192002-11-03 00:24:07 +00001071
1072 I2C_ACTIVE
1073
1074 The code necessary to make the I2C data line active
1075 (driven). If the data line is open collector, this
1076 define can be null.
1077
wdenkb37c7e52003-06-30 16:24:52 +00001078 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1079
wdenkc6097192002-11-03 00:24:07 +00001080 I2C_TRISTATE
1081
1082 The code necessary to make the I2C data line tri-stated
1083 (inactive). If the data line is open collector, this
1084 define can be null.
1085
wdenkb37c7e52003-06-30 16:24:52 +00001086 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1087
wdenkc6097192002-11-03 00:24:07 +00001088 I2C_READ
1089
1090 Code that returns TRUE if the I2C data line is high,
1091 FALSE if it is low.
1092
wdenkb37c7e52003-06-30 16:24:52 +00001093 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1094
wdenkc6097192002-11-03 00:24:07 +00001095 I2C_SDA(bit)
1096
1097 If <bit> is TRUE, sets the I2C data line high. If it
1098 is FALSE, it clears it (low).
1099
wdenkb37c7e52003-06-30 16:24:52 +00001100 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001101 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1102 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001103
wdenkc6097192002-11-03 00:24:07 +00001104 I2C_SCL(bit)
1105
1106 If <bit> is TRUE, sets the I2C clock line high. If it
1107 is FALSE, it clears it (low).
1108
wdenkb37c7e52003-06-30 16:24:52 +00001109 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001110 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1111 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001112
wdenkc6097192002-11-03 00:24:07 +00001113 I2C_DELAY
1114
1115 This delay is invoked four times per clock cycle so this
1116 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001117 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001118 like:
1119
wdenkb37c7e52003-06-30 16:24:52 +00001120 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001121
wdenk47cd00f2003-03-06 13:39:27 +00001122 CFG_I2C_INIT_BOARD
1123
wdenk8bde7f72003-06-27 21:31:46 +00001124 When a board is reset during an i2c bus transfer
1125 chips might think that the current transfer is still
1126 in progress. On some boards it is possible to access
1127 the i2c SCLK line directly, either by using the
1128 processor pin as a GPIO or by having a second pin
1129 connected to the bus. If this option is defined a
1130 custom i2c_init_board() routine in boards/xxx/board.c
1131 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001132
wdenkc6097192002-11-03 00:24:07 +00001133- SPI Support: CONFIG_SPI
1134
1135 Enables SPI driver (so far only tested with
1136 SPI EEPROM, also an instance works with Crystal A/D and
1137 D/As on the SACSng board)
1138
1139 CONFIG_SPI_X
1140
1141 Enables extended (16-bit) SPI EEPROM addressing.
1142 (symmetrical to CONFIG_I2C_X)
1143
1144 CONFIG_SOFT_SPI
1145
wdenk43d96162003-03-06 00:02:04 +00001146 Enables a software (bit-bang) SPI driver rather than
1147 using hardware support. This is a general purpose
1148 driver that only requires three general I/O port pins
1149 (two outputs, one input) to function. If this is
1150 defined, the board configuration must define several
1151 SPI configuration items (port pins to use, etc). For
1152 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001153
1154- FPGA Support: CONFIG_FPGA_COUNT
1155
wdenk43d96162003-03-06 00:02:04 +00001156 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001157
wdenk43d96162003-03-06 00:02:04 +00001158 CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +00001159
wdenk43d96162003-03-06 00:02:04 +00001160 Used to specify the types of FPGA devices. For
wdenkc6097192002-11-03 00:24:07 +00001161 example,
wdenk8bde7f72003-06-27 21:31:46 +00001162 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
wdenkc6097192002-11-03 00:24:07 +00001163
wdenk8bde7f72003-06-27 21:31:46 +00001164 CFG_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001165
wdenk43d96162003-03-06 00:02:04 +00001166 Enable printing of hash marks during FPGA
wdenkc6097192002-11-03 00:24:07 +00001167 configuration.
1168
1169 CFG_FPGA_CHECK_BUSY
1170
wdenk43d96162003-03-06 00:02:04 +00001171 Enable checks on FPGA configuration interface busy
1172 status by the configuration function. This option
1173 will require a board or device specific function to
1174 be written.
wdenkc6097192002-11-03 00:24:07 +00001175
1176 CONFIG_FPGA_DELAY
1177
wdenk43d96162003-03-06 00:02:04 +00001178 If defined, a function that provides delays in the
1179 FPGA configuration driver.
wdenkc6097192002-11-03 00:24:07 +00001180
1181 CFG_FPGA_CHECK_CTRLC
1182
1183 Allow Control-C to interrupt FPGA configuration
1184
1185 CFG_FPGA_CHECK_ERROR
1186
wdenk43d96162003-03-06 00:02:04 +00001187 Check for configuration errors during FPGA bitfile
1188 loading. For example, abort during Virtex II
1189 configuration if the INIT_B line goes low (which
1190 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001191
1192 CFG_FPGA_WAIT_INIT
1193
wdenk43d96162003-03-06 00:02:04 +00001194 Maximum time to wait for the INIT_B line to deassert
1195 after PROB_B has been deasserted during a Virtex II
1196 FPGA configuration sequence. The default time is 500 mS.
wdenkc6097192002-11-03 00:24:07 +00001197
1198 CFG_FPGA_WAIT_BUSY
1199
wdenk43d96162003-03-06 00:02:04 +00001200 Maximum time to wait for BUSY to deassert during
1201 Virtex II FPGA configuration. The default is 5 mS.
wdenkc6097192002-11-03 00:24:07 +00001202
1203 CFG_FPGA_WAIT_CONFIG
1204
wdenk43d96162003-03-06 00:02:04 +00001205 Time to wait after FPGA configuration. The default is
wdenkc6097192002-11-03 00:24:07 +00001206 200 mS.
1207
1208- FPGA Support: CONFIG_FPGA_COUNT
1209
wdenk8bde7f72003-06-27 21:31:46 +00001210 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001211
wdenk8bde7f72003-06-27 21:31:46 +00001212 CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +00001213
wdenk8bde7f72003-06-27 21:31:46 +00001214 Used to specify the types of FPGA devices. For example,
1215 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
wdenkc6097192002-11-03 00:24:07 +00001216
wdenk8bde7f72003-06-27 21:31:46 +00001217 CFG_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001218
wdenk8bde7f72003-06-27 21:31:46 +00001219 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001220
1221 CFG_FPGA_CHECK_BUSY
1222
wdenk43d96162003-03-06 00:02:04 +00001223 Enable checks on FPGA configuration interface busy
1224 status by the configuration function. This option
1225 will require a board or device specific function to
1226 be written.
wdenkc6097192002-11-03 00:24:07 +00001227
1228 CONFIG_FPGA_DELAY
1229
1230 If defined, a function that provides delays in the FPGA
1231 configuration driver.
1232
1233 CFG_FPGA_CHECK_CTRLC
1234 Allow Control-C to interrupt FPGA configuration
1235
1236 CFG_FPGA_CHECK_ERROR
1237
wdenk43d96162003-03-06 00:02:04 +00001238 Check for configuration errors during FPGA bitfile
1239 loading. For example, abort during Virtex II
1240 configuration if the INIT_B line goes low (which
1241 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001242
1243 CFG_FPGA_WAIT_INIT
1244
wdenk43d96162003-03-06 00:02:04 +00001245 Maximum time to wait for the INIT_B line to deassert
1246 after PROB_B has been deasserted during a Virtex II
1247 FPGA configuration sequence. The default time is 500
1248 mS.
wdenkc6097192002-11-03 00:24:07 +00001249
1250 CFG_FPGA_WAIT_BUSY
1251
wdenk43d96162003-03-06 00:02:04 +00001252 Maximum time to wait for BUSY to deassert during
1253 Virtex II FPGA configuration. The default is 5 mS.
wdenkc6097192002-11-03 00:24:07 +00001254
1255 CFG_FPGA_WAIT_CONFIG
1256
wdenk43d96162003-03-06 00:02:04 +00001257 Time to wait after FPGA configuration. The default is
1258 200 mS.
wdenkc6097192002-11-03 00:24:07 +00001259
1260- Configuration Management:
1261 CONFIG_IDENT_STRING
1262
wdenk43d96162003-03-06 00:02:04 +00001263 If defined, this string will be added to the U-Boot
1264 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00001265
1266- Vendor Parameter Protection:
1267
wdenk43d96162003-03-06 00:02:04 +00001268 U-Boot considers the values of the environment
1269 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00001270 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00001271 are set once by the board vendor / manufacturer, and
1272 protects these variables from casual modification by
1273 the user. Once set, these variables are read-only,
1274 and write or delete attempts are rejected. You can
1275 change this behviour:
wdenkc6097192002-11-03 00:24:07 +00001276
1277 If CONFIG_ENV_OVERWRITE is #defined in your config
1278 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00001279 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001280 these parameters.
1281
1282 Alternatively, if you #define _both_ CONFIG_ETHADDR
1283 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1284 ethernet address is installed in the environment,
1285 which can be changed exactly ONCE by the user. [The
1286 serial# is unaffected by this, i. e. it remains
1287 read-only.]
1288
1289- Protected RAM:
1290 CONFIG_PRAM
1291
1292 Define this variable to enable the reservation of
1293 "protected RAM", i. e. RAM which is not overwritten
1294 by U-Boot. Define CONFIG_PRAM to hold the number of
1295 kB you want to reserve for pRAM. You can overwrite
1296 this default value by defining an environment
1297 variable "pram" to the number of kB you want to
1298 reserve. Note that the board info structure will
1299 still show the full amount of RAM. If pRAM is
1300 reserved, a new environment variable "mem" will
1301 automatically be defined to hold the amount of
1302 remaining RAM in a form that can be passed as boot
1303 argument to Linux, for instance like that:
1304
1305 setenv bootargs ... mem=\$(mem)
1306 saveenv
1307
1308 This way you can tell Linux not to use this memory,
1309 either, which results in a memory region that will
1310 not be affected by reboots.
1311
1312 *WARNING* If your board configuration uses automatic
1313 detection of the RAM size, you must make sure that
1314 this memory test is non-destructive. So far, the
1315 following board configurations are known to be
1316 "pRAM-clean":
1317
1318 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1319 HERMES, IP860, RPXlite, LWMON, LANTEC,
1320 PCU_E, FLAGADM, TQM8260
1321
1322- Error Recovery:
1323 CONFIG_PANIC_HANG
1324
1325 Define this variable to stop the system in case of a
1326 fatal error, so that you have to reset it manually.
1327 This is probably NOT a good idea for an embedded
1328 system where you want to system to reboot
1329 automatically as fast as possible, but it may be
1330 useful during development since you can try to debug
1331 the conditions that lead to the situation.
1332
1333 CONFIG_NET_RETRY_COUNT
1334
wdenk43d96162003-03-06 00:02:04 +00001335 This variable defines the number of retries for
1336 network operations like ARP, RARP, TFTP, or BOOTP
1337 before giving up the operation. If not defined, a
1338 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00001339
1340- Command Interpreter:
1341 CFG_HUSH_PARSER
1342
1343 Define this variable to enable the "hush" shell (from
1344 Busybox) as command line interpreter, thus enabling
1345 powerful command line syntax like
1346 if...then...else...fi conditionals or `&&' and '||'
1347 constructs ("shell scripts").
1348
1349 If undefined, you get the old, much simpler behaviour
1350 with a somewhat smaller memory footprint.
1351
1352
1353 CFG_PROMPT_HUSH_PS2
1354
1355 This defines the secondary prompt string, which is
1356 printed when the command interpreter needs more input
1357 to complete a command. Usually "> ".
1358
1359 Note:
1360
wdenk8bde7f72003-06-27 21:31:46 +00001361 In the current implementation, the local variables
1362 space and global environment variables space are
1363 separated. Local variables are those you define by
1364 simply typing `name=value'. To access a local
1365 variable later on, you have write `$name' or
1366 `${name}'; to execute the contents of a variable
1367 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001368
wdenk43d96162003-03-06 00:02:04 +00001369 Global environment variables are those you use
1370 setenv/printenv to work with. To run a command stored
1371 in such a variable, you need to use the run command,
1372 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001373
1374 To store commands and special characters in a
1375 variable, please use double quotation marks
1376 surrounding the whole text of the variable, instead
1377 of the backslashes before semicolons and special
1378 symbols.
1379
wdenka8c7c702003-12-06 19:49:23 +00001380- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00001381 CONFIG_EXTRA_ENV_SETTINGS
1382
wdenk43d96162003-03-06 00:02:04 +00001383 Define this to contain any number of null terminated
1384 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00001385 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00001386
wdenk43d96162003-03-06 00:02:04 +00001387 For example, place something like this in your
1388 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001389
1390 #define CONFIG_EXTRA_ENV_SETTINGS \
1391 "myvar1=value1\0" \
1392 "myvar2=value2\0"
1393
wdenk43d96162003-03-06 00:02:04 +00001394 Warning: This method is based on knowledge about the
1395 internal format how the environment is stored by the
1396 U-Boot code. This is NOT an official, exported
1397 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00001398 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001399 You better know what you are doing here.
1400
wdenk43d96162003-03-06 00:02:04 +00001401 Note: overly (ab)use of the default environment is
1402 discouraged. Make sure to check other ways to preset
1403 the environment like the autoscript function or the
1404 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001405
wdenka8c7c702003-12-06 19:49:23 +00001406- DataFlash Support:
wdenk2abbe072003-06-16 23:50:08 +00001407 CONFIG_HAS_DATAFLASH
1408
wdenk8bde7f72003-06-27 21:31:46 +00001409 Defining this option enables DataFlash features and
1410 allows to read/write in Dataflash via the standard
1411 commands cp, md...
wdenk2abbe072003-06-16 23:50:08 +00001412
wdenka8c7c702003-12-06 19:49:23 +00001413- Show boot progress:
wdenkc6097192002-11-03 00:24:07 +00001414 CONFIG_SHOW_BOOT_PROGRESS
1415
wdenk43d96162003-03-06 00:02:04 +00001416 Defining this option allows to add some board-
1417 specific code (calling a user-provided function
1418 "show_boot_progress(int)") that enables you to show
1419 the system's boot progress on some display (for
1420 example, some LED's) on your board. At the moment,
1421 the following checkpoints are implemented:
wdenkc6097192002-11-03 00:24:07 +00001422
1423 Arg Where When
1424 1 common/cmd_bootm.c before attempting to boot an image
1425 -1 common/cmd_bootm.c Image header has bad magic number
1426 2 common/cmd_bootm.c Image header has correct magic number
1427 -2 common/cmd_bootm.c Image header has bad checksum
1428 3 common/cmd_bootm.c Image header has correct checksum
1429 -3 common/cmd_bootm.c Image data has bad checksum
1430 4 common/cmd_bootm.c Image data has correct checksum
1431 -4 common/cmd_bootm.c Image is for unsupported architecture
1432 5 common/cmd_bootm.c Architecture check OK
1433 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1434 6 common/cmd_bootm.c Image Type check OK
1435 -6 common/cmd_bootm.c gunzip uncompression error
1436 -7 common/cmd_bootm.c Unimplemented compression type
1437 7 common/cmd_bootm.c Uncompression OK
1438 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1439 8 common/cmd_bootm.c Image Type check OK
1440 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1441 9 common/cmd_bootm.c Start initial ramdisk verification
1442 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1443 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1444 10 common/cmd_bootm.c Ramdisk header is OK
1445 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1446 11 common/cmd_bootm.c Ramdisk data has correct checksum
1447 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1448 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1449 13 common/cmd_bootm.c Start multifile image verification
1450 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1451 15 common/cmd_bootm.c All preparation done, transferring control to OS
1452
1453 -1 common/cmd_doc.c Bad usage of "doc" command
1454 -1 common/cmd_doc.c No boot device
1455 -1 common/cmd_doc.c Unknown Chip ID on boot device
1456 -1 common/cmd_doc.c Read Error on boot device
1457 -1 common/cmd_doc.c Image header has bad magic number
1458
1459 -1 common/cmd_ide.c Bad usage of "ide" command
1460 -1 common/cmd_ide.c No boot device
1461 -1 common/cmd_ide.c Unknown boot device
1462 -1 common/cmd_ide.c Unknown partition table
1463 -1 common/cmd_ide.c Invalid partition type
1464 -1 common/cmd_ide.c Read Error on boot device
1465 -1 common/cmd_ide.c Image header has bad magic number
1466
wdenk206c60c2003-09-18 10:02:25 +00001467 -1 common/cmd_nand.c Bad usage of "nand" command
1468 -1 common/cmd_nand.c No boot device
1469 -1 common/cmd_nand.c Unknown Chip ID on boot device
1470 -1 common/cmd_nand.c Read Error on boot device
1471 -1 common/cmd_nand.c Image header has bad magic number
1472
1473 -1 common/env_common.c Environment has a bad CRC, using default
wdenkc6097192002-11-03 00:24:07 +00001474
1475
1476Modem Support:
1477--------------
1478
wdenk85ec0bc2003-03-31 16:34:49 +00001479[so far only for SMDK2400 and TRAB boards]
wdenkc6097192002-11-03 00:24:07 +00001480
1481- Modem support endable:
1482 CONFIG_MODEM_SUPPORT
1483
1484- RTS/CTS Flow control enable:
1485 CONFIG_HWFLOW
1486
1487- Modem debug support:
1488 CONFIG_MODEM_SUPPORT_DEBUG
1489
wdenk43d96162003-03-06 00:02:04 +00001490 Enables debugging stuff (char screen[1024], dbg())
1491 for modem support. Useful only with BDI2000.
wdenkc6097192002-11-03 00:24:07 +00001492
wdenka8c7c702003-12-06 19:49:23 +00001493- Interrupt support (PPC):
1494
wdenkd4ca31c2004-01-02 14:00:00 +00001495 There are common interrupt_init() and timer_interrupt()
1496 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1497 for cpu specific initialization. interrupt_init_cpu()
1498 should set decrementer_count to appropriate value. If
1499 cpu resets decrementer automatically after interrupt
1500 (ppc4xx) it should set decrementer_count to zero.
1501 timer_interrupt() calls timer_interrupt_cpu() for cpu
1502 specific handling. If board has watchdog / status_led
1503 / other_activity_monitor it works automatically from
1504 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00001505
wdenkc6097192002-11-03 00:24:07 +00001506- General:
1507
wdenk43d96162003-03-06 00:02:04 +00001508 In the target system modem support is enabled when a
1509 specific key (key combination) is pressed during
1510 power-on. Otherwise U-Boot will boot normally
1511 (autoboot). The key_pressed() fuction is called from
1512 board_init(). Currently key_pressed() is a dummy
1513 function, returning 1 and thus enabling modem
1514 initialization.
wdenkc6097192002-11-03 00:24:07 +00001515
wdenk43d96162003-03-06 00:02:04 +00001516 If there are no modem init strings in the
1517 environment, U-Boot proceed to autoboot; the
1518 previous output (banner, info printfs) will be
1519 supressed, though.
wdenkc6097192002-11-03 00:24:07 +00001520
1521 See also: doc/README.Modem
1522
1523
wdenkc6097192002-11-03 00:24:07 +00001524Configuration Settings:
1525-----------------------
1526
1527- CFG_LONGHELP: Defined when you want long help messages included;
1528 undefine this when you're short of memory.
1529
1530- CFG_PROMPT: This is what U-Boot prints on the console to
1531 prompt for user input.
1532
1533- CFG_CBSIZE: Buffer size for input from the Console
1534
1535- CFG_PBSIZE: Buffer size for Console output
1536
1537- CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1538
1539- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1540 the application (usually a Linux kernel) when it is
1541 booted
1542
1543- CFG_BAUDRATE_TABLE:
1544 List of legal baudrate settings for this board.
1545
1546- CFG_CONSOLE_INFO_QUIET
wdenk8bde7f72003-06-27 21:31:46 +00001547 Suppress display of console information at boot.
wdenkc6097192002-11-03 00:24:07 +00001548
1549- CFG_CONSOLE_IS_IN_ENV
wdenk8bde7f72003-06-27 21:31:46 +00001550 If the board specific function
1551 extern int overwrite_console (void);
1552 returns 1, the stdin, stderr and stdout are switched to the
wdenkc6097192002-11-03 00:24:07 +00001553 serial port, else the settings in the environment are used.
1554
1555- CFG_CONSOLE_OVERWRITE_ROUTINE
wdenk8bde7f72003-06-27 21:31:46 +00001556 Enable the call to overwrite_console().
wdenkc6097192002-11-03 00:24:07 +00001557
1558- CFG_CONSOLE_ENV_OVERWRITE
1559 Enable overwrite of previous console environment settings.
1560
1561- CFG_MEMTEST_START, CFG_MEMTEST_END:
1562 Begin and End addresses of the area used by the
1563 simple memory test.
1564
1565- CFG_ALT_MEMTEST:
wdenk8bde7f72003-06-27 21:31:46 +00001566 Enable an alternate, more extensive memory test.
wdenkc6097192002-11-03 00:24:07 +00001567
wdenk5f535fe2003-09-18 09:21:33 +00001568- CFG_MEMTEST_SCRATCH:
1569 Scratch address used by the alternate memory test
1570 You only need to set this if address zero isn't writeable
1571
wdenkc6097192002-11-03 00:24:07 +00001572- CFG_TFTP_LOADADDR:
1573 Default load address for network file downloads
1574
1575- CFG_LOADS_BAUD_CHANGE:
1576 Enable temporary baudrate change while serial download
1577
1578- CFG_SDRAM_BASE:
1579 Physical start address of SDRAM. _Must_ be 0 here.
1580
1581- CFG_MBIO_BASE:
1582 Physical start address of Motherboard I/O (if using a
1583 Cogent motherboard)
1584
1585- CFG_FLASH_BASE:
1586 Physical start address of Flash memory.
1587
1588- CFG_MONITOR_BASE:
1589 Physical start address of boot monitor code (set by
1590 make config files to be same as the text base address
1591 (TEXT_BASE) used when linking) - same as
1592 CFG_FLASH_BASE when booting from flash.
1593
1594- CFG_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00001595 Size of memory reserved for monitor code, used to
1596 determine _at_compile_time_ (!) if the environment is
1597 embedded within the U-Boot image, or in a separate
1598 flash sector.
wdenkc6097192002-11-03 00:24:07 +00001599
1600- CFG_MALLOC_LEN:
1601 Size of DRAM reserved for malloc() use.
1602
1603- CFG_BOOTMAPSZ:
1604 Maximum size of memory mapped by the startup code of
1605 the Linux kernel; all data that must be processed by
1606 the Linux kernel (bd_info, boot arguments, eventually
1607 initrd image) must be put below this limit.
1608
1609- CFG_MAX_FLASH_BANKS:
1610 Max number of Flash memory banks
1611
1612- CFG_MAX_FLASH_SECT:
1613 Max number of sectors on a Flash chip
1614
1615- CFG_FLASH_ERASE_TOUT:
1616 Timeout for Flash erase operations (in ms)
1617
1618- CFG_FLASH_WRITE_TOUT:
1619 Timeout for Flash write operations (in ms)
1620
wdenk8564acf2003-07-14 22:13:32 +00001621- CFG_FLASH_LOCK_TOUT
1622 Timeout for Flash set sector lock bit operation (in ms)
1623
1624- CFG_FLASH_UNLOCK_TOUT
1625 Timeout for Flash clear lock bits operation (in ms)
1626
1627- CFG_FLASH_PROTECTION
1628 If defined, hardware flash sectors protection is used
1629 instead of U-Boot software protection.
1630
wdenkc6097192002-11-03 00:24:07 +00001631- CFG_DIRECT_FLASH_TFTP:
1632
1633 Enable TFTP transfers directly to flash memory;
1634 without this option such a download has to be
1635 performed in two steps: (1) download to RAM, and (2)
1636 copy from RAM to flash.
1637
1638 The two-step approach is usually more reliable, since
1639 you can check if the download worked before you erase
1640 the flash, but in some situations (when sytem RAM is
1641 too limited to allow for a tempory copy of the
1642 downloaded image) this option may be very useful.
1643
1644- CFG_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00001645 Define if the flash driver uses extra elements in the
1646 common flash structure for storing flash geometry
wdenkc6097192002-11-03 00:24:07 +00001647
stroese53cf9432003-06-05 15:39:44 +00001648- CFG_RX_ETH_BUFFER:
1649 Defines the number of ethernet receive buffers. On some
1650 ethernet controllers it is recommended to set this value
1651 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1652 buffers can be full shortly after enabling the interface
1653 on high ethernet traffic.
1654 Defaults to 4 if not defined.
1655
wdenkc6097192002-11-03 00:24:07 +00001656The following definitions that deal with the placement and management
1657of environment data (variable area); in general, we support the
1658following configurations:
1659
1660- CFG_ENV_IS_IN_FLASH:
1661
1662 Define this if the environment is in flash memory.
1663
1664 a) The environment occupies one whole flash sector, which is
1665 "embedded" in the text segment with the U-Boot code. This
1666 happens usually with "bottom boot sector" or "top boot
1667 sector" type flash chips, which have several smaller
1668 sectors at the start or the end. For instance, such a
1669 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1670 such a case you would place the environment in one of the
1671 4 kB sectors - with U-Boot code before and after it. With
1672 "top boot sector" type flash chips, you would put the
1673 environment in one of the last sectors, leaving a gap
1674 between U-Boot and the environment.
1675
1676 - CFG_ENV_OFFSET:
1677
1678 Offset of environment data (variable area) to the
1679 beginning of flash memory; for instance, with bottom boot
1680 type flash chips the second sector can be used: the offset
1681 for this sector is given here.
1682
1683 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1684
1685 - CFG_ENV_ADDR:
1686
1687 This is just another way to specify the start address of
1688 the flash sector containing the environment (instead of
1689 CFG_ENV_OFFSET).
1690
1691 - CFG_ENV_SECT_SIZE:
1692
1693 Size of the sector containing the environment.
1694
1695
1696 b) Sometimes flash chips have few, equal sized, BIG sectors.
1697 In such a case you don't want to spend a whole sector for
1698 the environment.
1699
1700 - CFG_ENV_SIZE:
1701
1702 If you use this in combination with CFG_ENV_IS_IN_FLASH
1703 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1704 of this flash sector for the environment. This saves
1705 memory for the RAM copy of the environment.
1706
1707 It may also save flash memory if you decide to use this
1708 when your environment is "embedded" within U-Boot code,
1709 since then the remainder of the flash sector could be used
1710 for U-Boot code. It should be pointed out that this is
1711 STRONGLY DISCOURAGED from a robustness point of view:
1712 updating the environment in flash makes it always
1713 necessary to erase the WHOLE sector. If something goes
1714 wrong before the contents has been restored from a copy in
1715 RAM, your target system will be dead.
1716
1717 - CFG_ENV_ADDR_REDUND
1718 CFG_ENV_SIZE_REDUND
1719
wdenk43d96162003-03-06 00:02:04 +00001720 These settings describe a second storage area used to hold
1721 a redundand copy of the environment data, so that there is
wdenk3e386912003-04-05 00:53:31 +00001722 a valid backup copy in case there is a power failure during
wdenk43d96162003-03-06 00:02:04 +00001723 a "saveenv" operation.
wdenkc6097192002-11-03 00:24:07 +00001724
1725BE CAREFUL! Any changes to the flash layout, and some changes to the
1726source code will make it necessary to adapt <board>/u-boot.lds*
1727accordingly!
1728
1729
1730- CFG_ENV_IS_IN_NVRAM:
1731
1732 Define this if you have some non-volatile memory device
1733 (NVRAM, battery buffered SRAM) which you want to use for the
1734 environment.
1735
1736 - CFG_ENV_ADDR:
1737 - CFG_ENV_SIZE:
1738
1739 These two #defines are used to determin the memory area you
1740 want to use for environment. It is assumed that this memory
1741 can just be read and written to, without any special
1742 provision.
1743
1744BE CAREFUL! The first access to the environment happens quite early
1745in U-Boot initalization (when we try to get the setting of for the
1746console baudrate). You *MUST* have mappend your NVRAM area then, or
1747U-Boot will hang.
1748
1749Please note that even with NVRAM we still use a copy of the
1750environment in RAM: we could work on NVRAM directly, but we want to
1751keep settings there always unmodified except somebody uses "saveenv"
1752to save the current settings.
1753
1754
1755- CFG_ENV_IS_IN_EEPROM:
1756
1757 Use this if you have an EEPROM or similar serial access
1758 device and a driver for it.
1759
1760 - CFG_ENV_OFFSET:
1761 - CFG_ENV_SIZE:
1762
1763 These two #defines specify the offset and size of the
1764 environment area within the total memory of your EEPROM.
1765
1766 - CFG_I2C_EEPROM_ADDR:
1767 If defined, specified the chip address of the EEPROM device.
1768 The default address is zero.
1769
1770 - CFG_EEPROM_PAGE_WRITE_BITS:
1771 If defined, the number of bits used to address bytes in a
1772 single page in the EEPROM device. A 64 byte page, for example
1773 would require six bits.
1774
1775 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1776 If defined, the number of milliseconds to delay between
1777 page writes. The default is zero milliseconds.
1778
1779 - CFG_I2C_EEPROM_ADDR_LEN:
1780 The length in bytes of the EEPROM memory array address. Note
1781 that this is NOT the chip address length!
1782
1783 - CFG_EEPROM_SIZE:
1784 The size in bytes of the EEPROM device.
1785
wdenkc6097192002-11-03 00:24:07 +00001786
wdenk5779d8d2003-12-06 23:55:10 +00001787- CFG_ENV_IS_IN_DATAFLASH:
1788
wdenkd4ca31c2004-01-02 14:00:00 +00001789 Define this if you have a DataFlash memory device which you
wdenk5779d8d2003-12-06 23:55:10 +00001790 want to use for the environment.
1791
1792 - CFG_ENV_OFFSET:
1793 - CFG_ENV_ADDR:
1794 - CFG_ENV_SIZE:
1795
1796 These three #defines specify the offset and size of the
1797 environment area within the total memory of your DataFlash placed
1798 at the specified address.
1799
1800
wdenkc6097192002-11-03 00:24:07 +00001801- CFG_SPI_INIT_OFFSET
1802
1803 Defines offset to the initial SPI buffer area in DPRAM. The
1804 area is used at an early stage (ROM part) if the environment
1805 is configured to reside in the SPI EEPROM: We need a 520 byte
1806 scratch DPRAM area. It is used between the two initialization
1807 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1808 to be a good choice since it makes it far enough from the
1809 start of the data area as well as from the stack pointer.
1810
1811Please note that the environment is read-only as long as the monitor
1812has been relocated to RAM and a RAM copy of the environment has been
1813created; also, when using EEPROM you will have to use getenv_r()
1814until then to read environment variables.
1815
wdenk85ec0bc2003-03-31 16:34:49 +00001816The environment is protected by a CRC32 checksum. Before the monitor
1817is relocated into RAM, as a result of a bad CRC you will be working
1818with the compiled-in default environment - *silently*!!! [This is
1819necessary, because the first environment variable we need is the
1820"baudrate" setting for the console - if we have a bad CRC, we don't
1821have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001822
1823Note: once the monitor has been relocated, then it will complain if
1824the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00001825use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001826
wdenkfc3e2162003-10-08 22:33:00 +00001827- CFG_FAULT_ECHO_LINK_DOWN:
wdenk42d1f032003-10-15 23:53:47 +00001828 Echo the inverted Ethernet link state to the fault LED.
wdenkfc3e2162003-10-08 22:33:00 +00001829
1830 Note: If this option is active, then CFG_FAULT_MII_ADDR
1831 also needs to be defined.
1832
1833- CFG_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00001834 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001835
wdenkc6097192002-11-03 00:24:07 +00001836Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00001837---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001838
1839- CFG_CACHELINE_SIZE:
1840 Cache Line Size of the CPU.
1841
1842- CFG_DEFAULT_IMMR:
1843 Default address of the IMMR after system reset.
wdenk2535d602003-07-17 23:16:40 +00001844
wdenk42d1f032003-10-15 23:53:47 +00001845 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1846 and RPXsuper) to be able to adjust the position of
1847 the IMMR register after a reset.
wdenkc6097192002-11-03 00:24:07 +00001848
wdenk7f6c2cb2002-11-10 22:06:23 +00001849- Floppy Disk Support:
1850 CFG_FDC_DRIVE_NUMBER
1851
1852 the default drive number (default value 0)
1853
1854 CFG_ISA_IO_STRIDE
1855
1856 defines the spacing between fdc chipset registers
1857 (default value 1)
1858
1859 CFG_ISA_IO_OFFSET
1860
wdenk43d96162003-03-06 00:02:04 +00001861 defines the offset of register from address. It
1862 depends on which part of the data bus is connected to
1863 the fdc chipset. (default value 0)
wdenk7f6c2cb2002-11-10 22:06:23 +00001864
wdenk43d96162003-03-06 00:02:04 +00001865 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1866 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1867 default value.
wdenk7f6c2cb2002-11-10 22:06:23 +00001868
wdenk43d96162003-03-06 00:02:04 +00001869 if CFG_FDC_HW_INIT is defined, then the function
1870 fdc_hw_init() is called at the beginning of the FDC
1871 setup. fdc_hw_init() must be provided by the board
1872 source code. It is used to make hardware dependant
1873 initializations.
wdenk7f6c2cb2002-11-10 22:06:23 +00001874
wdenkc6097192002-11-03 00:24:07 +00001875- CFG_IMMR: Physical address of the Internal Memory Mapped
1876 Register; DO NOT CHANGE! (11-4)
1877 [MPC8xx systems only]
1878
1879- CFG_INIT_RAM_ADDR:
1880
wdenk7152b1d2003-09-05 23:19:14 +00001881 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001882 initial data and stack; please note that this must be
1883 writable memory that is working WITHOUT special
1884 initialization, i. e. you CANNOT use normal RAM which
1885 will become available only after programming the
1886 memory controller and running certain initialization
1887 sequences.
1888
1889 U-Boot uses the following memory types:
1890 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1891 - MPC824X: data cache
1892 - PPC4xx: data cache
1893
wdenk85ec0bc2003-03-31 16:34:49 +00001894- CFG_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00001895
1896 Offset of the initial data structure in the memory
1897 area defined by CFG_INIT_RAM_ADDR. Usually
wdenk85ec0bc2003-03-31 16:34:49 +00001898 CFG_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00001899 data is located at the end of the available space
1900 (sometimes written as (CFG_INIT_RAM_END -
1901 CFG_INIT_DATA_SIZE), and the initial stack is just
1902 below that area (growing from (CFG_INIT_RAM_ADDR +
wdenk85ec0bc2003-03-31 16:34:49 +00001903 CFG_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00001904
1905 Note:
1906 On the MPC824X (or other systems that use the data
1907 cache for initial memory) the address chosen for
1908 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1909 point to an otherwise UNUSED address space between
1910 the top of RAM and the start of the PCI space.
1911
1912- CFG_SIUMCR: SIU Module Configuration (11-6)
1913
1914- CFG_SYPCR: System Protection Control (11-9)
1915
1916- CFG_TBSCR: Time Base Status and Control (11-26)
1917
1918- CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1919
1920- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1921
1922- CFG_SCCR: System Clock and reset Control Register (15-27)
1923
1924- CFG_OR_TIMING_SDRAM:
1925 SDRAM timing
1926
1927- CFG_MAMR_PTA:
1928 periodic timer for refresh
1929
1930- CFG_DER: Debug Event Register (37-47)
1931
1932- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1933 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1934 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1935 CFG_BR1_PRELIM:
1936 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1937
1938- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1939 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1940 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1941 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1942
1943- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1944 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1945 Machine Mode Register and Memory Periodic Timer
1946 Prescaler definitions (SDRAM timing)
1947
1948- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1949 enable I2C microcode relocation patch (MPC8xx);
1950 define relocation offset in DPRAM [DSP2]
1951
1952- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1953 enable SPI microcode relocation patch (MPC8xx);
1954 define relocation offset in DPRAM [SCC4]
1955
1956- CFG_USE_OSCCLK:
1957 Use OSCM clock mode on MBX8xx board. Be careful,
1958 wrong setting might damage your board. Read
1959 doc/README.MBX before setting this variable!
1960
wdenkea909b72002-11-21 23:11:29 +00001961- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
wdenk43d96162003-03-06 00:02:04 +00001962 Offset of the bootmode word in DPRAM used by post
1963 (Power On Self Tests). This definition overrides
1964 #define'd default value in commproc.h resp.
1965 cpm_8260.h.
wdenkea909b72002-11-21 23:11:29 +00001966
stroese1d49b1f2003-05-23 11:39:05 +00001967- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
1968 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
1969 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
1970 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
1971 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
1972 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
1973 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
wdenk5d232d02003-05-22 22:52:13 +00001974 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
1975 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
1976
wdenkc6097192002-11-03 00:24:07 +00001977Building the Software:
1978======================
1979
1980Building U-Boot has been tested in native PPC environments (on a
1981PowerBook G3 running LinuxPPC 2000) and in cross environments
1982(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1983NetBSD 1.5 on x86).
1984
1985If you are not using a native PPC environment, it is assumed that you
1986have the GNU cross compiling tools available in your path and named
1987with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1988you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1989the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1990change it to:
1991
1992 CROSS_COMPILE = ppc_4xx-
1993
1994
1995U-Boot is intended to be simple to build. After installing the
1996sources you must configure U-Boot for one specific board type. This
1997is done by typing:
1998
1999 make NAME_config
2000
2001where "NAME_config" is the name of one of the existing
2002configurations; the following names are supported:
2003
2004 ADCIOP_config GTH_config TQM850L_config
2005 ADS860_config IP860_config TQM855L_config
2006 AR405_config IVML24_config TQM860L_config
2007 CANBT_config IVMS8_config WALNUT405_config
2008 CPCI405_config LANTEC_config cogent_common_config
2009 CPCIISER4_config MBX_config cogent_mpc8260_config
2010 CU824_config MBX860T_config cogent_mpc8xx_config
2011 ESTEEM192E_config RPXlite_config hermes_config
2012 ETX094_config RPXsuper_config hymod_config
2013 FADS823_config SM850_config lwmon_config
2014 FADS850SAR_config SPD823TS_config pcu_e_config
2015 FADS860T_config SXNI855T_config rsdproto_config
2016 FPS850L_config Sandpoint8240_config sbc8260_config
2017 GENIETV_config TQM823L_config PIP405_config
wdenk384ae022002-11-05 00:17:55 +00002018 GEN860T_config EBONY_config FPS860L_config
wdenk7f70e852003-05-20 14:25:27 +00002019 ELPT860_config cmi_mpc5xx_config NETVIA_config
wdenk2535d602003-07-17 23:16:40 +00002020 at91rm9200dk_config omap1510inn_config MPC8260ADS_config
wdenk42d1f032003-10-15 23:53:47 +00002021 omap1610inn_config ZPC1900_config MPC8540ADS_config
wdenk3bbc8992003-12-07 22:27:15 +00002022 MPC8560ADS_config QS850_config QS823_config
wdenk180d3f72004-01-04 16:28:35 +00002023 QS860T_config DUET_ADS_config
wdenk54387ac2003-10-08 22:45:44 +00002024
wdenkc6097192002-11-03 00:24:07 +00002025Note: for some board special configuration names may exist; check if
2026 additional information is available from the board vendor; for
2027 instance, the TQM8xxL systems run normally at 50 MHz and use a
2028 SCC for 10baseT ethernet; there are also systems with 80 MHz
2029 CPU clock, and an optional Fast Ethernet module is available
2030 for CPU's with FEC. You can select such additional "features"
2031 when chosing the configuration, i. e.
2032
2033 make TQM860L_config
2034 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
2035
2036 make TQM860L_FEC_config
2037 - will configure for a TQM860L at 50MHz with FEC for ethernet
2038
2039 make TQM860L_80MHz_config
2040 - will configure for a TQM860L at 80 MHz, with normal 10baseT
2041 interface
2042
2043 make TQM860L_FEC_80MHz_config
2044 - will configure for a TQM860L at 80 MHz with FEC for ethernet
2045
2046 make TQM823L_LCD_config
2047 - will configure for a TQM823L with U-Boot console on LCD
2048
2049 make TQM823L_LCD_80MHz_config
2050 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
2051
2052 etc.
2053
2054
wdenk24ee89b2002-11-03 17:56:27 +00002055Finally, type "make all", and you should get some working U-Boot
wdenk7152b1d2003-09-05 23:19:14 +00002056images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00002057
2058- "u-boot.bin" is a raw binary image
2059- "u-boot" is an image in ELF binary format
2060- "u-boot.srec" is in Motorola S-Record format
2061
2062
2063Please be aware that the Makefiles assume you are using GNU make, so
2064for instance on NetBSD you might need to use "gmake" instead of
2065native "make".
2066
2067
2068If the system board that you have is not listed, then you will need
2069to port U-Boot to your hardware platform. To do this, follow these
2070steps:
2071
20721. Add a new configuration option for your board to the toplevel
wdenk85ec0bc2003-03-31 16:34:49 +00002073 "Makefile" and to the "MAKEALL" script, using the existing
2074 entries as examples. Note that here and at many other places
wdenk7152b1d2003-09-05 23:19:14 +00002075 boards and other names are listed in alphabetical sort order. Please
wdenk85ec0bc2003-03-31 16:34:49 +00002076 keep this order.
wdenkc6097192002-11-03 00:24:07 +000020772. Create a new directory to hold your board specific code. Add any
wdenk85ec0bc2003-03-31 16:34:49 +00002078 files you need. In your board directory, you will need at least
2079 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
20803. Create a new configuration file "include/configs/<board>.h" for
2081 your board
wdenkc6097192002-11-03 00:24:07 +000020823. If you're porting U-Boot to a new CPU, then also create a new
2083 directory to hold your CPU specific code. Add any files you need.
wdenk85ec0bc2003-03-31 16:34:49 +000020844. Run "make <board>_config" with your new name.
wdenkc6097192002-11-03 00:24:07 +000020855. Type "make", and you should get a working "u-boot.srec" file
2086 to be installed on your target system.
wdenk85ec0bc2003-03-31 16:34:49 +000020876. Debug and solve any problems that might arise.
wdenkc6097192002-11-03 00:24:07 +00002088 [Of course, this last step is much harder than it sounds.]
2089
2090
2091Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2092==============================================================
2093
2094If you have modified U-Boot sources (for instance added a new board
2095or support for new devices, a new CPU, etc.) you are expected to
2096provide feedback to the other developers. The feedback normally takes
2097the form of a "patch", i. e. a context diff against a certain (latest
2098official or latest in CVS) version of U-Boot sources.
2099
2100But before you submit such a patch, please verify that your modifi-
2101cation did not break existing code. At least make sure that *ALL* of
2102the supported boards compile WITHOUT ANY compiler warnings. To do so,
2103just run the "MAKEALL" script, which will configure and build U-Boot
2104for ALL supported system. Be warned, this will take a while. You can
wdenk7152b1d2003-09-05 23:19:14 +00002105select which (cross) compiler to use by passing a `CROSS_COMPILE'
wdenkc6097192002-11-03 00:24:07 +00002106environment variable to the script, i. e. to use the cross tools from
2107MontaVista's Hard Hat Linux you can type
2108
2109 CROSS_COMPILE=ppc_8xx- MAKEALL
2110
2111or to build on a native PowerPC system you can type
2112
2113 CROSS_COMPILE=' ' MAKEALL
2114
2115See also "U-Boot Porting Guide" below.
2116
2117
wdenkc6097192002-11-03 00:24:07 +00002118Monitor Commands - Overview:
2119============================
2120
2121go - start application at address 'addr'
2122run - run commands in an environment variable
2123bootm - boot application image from memory
2124bootp - boot image via network using BootP/TFTP protocol
2125tftpboot- boot image via network using TFTP protocol
2126 and env variables "ipaddr" and "serverip"
2127 (and eventually "gatewayip")
2128rarpboot- boot image via network using RARP/TFTP protocol
2129diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2130loads - load S-Record file over serial line
2131loadb - load binary file over serial line (kermit mode)
2132md - memory display
2133mm - memory modify (auto-incrementing)
2134nm - memory modify (constant address)
2135mw - memory write (fill)
2136cp - memory copy
2137cmp - memory compare
2138crc32 - checksum calculation
2139imd - i2c memory display
2140imm - i2c memory modify (auto-incrementing)
2141inm - i2c memory modify (constant address)
2142imw - i2c memory write (fill)
2143icrc32 - i2c checksum calculation
2144iprobe - probe to discover valid I2C chip addresses
2145iloop - infinite loop on address range
2146isdram - print SDRAM configuration information
2147sspi - SPI utility commands
2148base - print or set address offset
2149printenv- print environment variables
2150setenv - set environment variables
2151saveenv - save environment variables to persistent storage
2152protect - enable or disable FLASH write protection
2153erase - erase FLASH memory
2154flinfo - print FLASH memory information
2155bdinfo - print Board Info structure
2156iminfo - print header information for application image
2157coninfo - print console devices and informations
2158ide - IDE sub-system
2159loop - infinite loop on address range
2160mtest - simple RAM test
2161icache - enable or disable instruction cache
2162dcache - enable or disable data cache
2163reset - Perform RESET of the CPU
2164echo - echo args to console
2165version - print monitor version
2166help - print online help
2167? - alias for 'help'
2168
2169
2170Monitor Commands - Detailed Description:
2171========================================
2172
2173TODO.
2174
2175For now: just type "help <command>".
2176
2177
2178Environment Variables:
2179======================
2180
2181U-Boot supports user configuration using Environment Variables which
2182can be made persistent by saving to Flash memory.
2183
2184Environment Variables are set using "setenv", printed using
2185"printenv", and saved to Flash using "saveenv". Using "setenv"
2186without a value can be used to delete a variable from the
2187environment. As long as you don't save the environment you are
2188working with an in-memory copy. In case the Flash area containing the
2189environment is erased by accident, a default environment is provided.
2190
2191Some configuration options can be set using Environment Variables:
2192
2193 baudrate - see CONFIG_BAUDRATE
2194
2195 bootdelay - see CONFIG_BOOTDELAY
2196
2197 bootcmd - see CONFIG_BOOTCOMMAND
2198
2199 bootargs - Boot arguments when booting an RTOS image
2200
2201 bootfile - Name of the image to load with TFTP
2202
2203 autoload - if set to "no" (any string beginning with 'n'),
2204 "bootp" will just load perform a lookup of the
2205 configuration from the BOOTP server, but not try to
2206 load any image using TFTP
2207
2208 autostart - if set to "yes", an image loaded using the "bootp",
2209 "rarpboot", "tftpboot" or "diskboot" commands will
2210 be automatically started (by internally calling
2211 "bootm")
2212
wdenk4a6fd342003-04-12 23:38:12 +00002213 If set to "no", a standalone image passed to the
2214 "bootm" command will be copied to the load address
2215 (and eventually uncompressed), but NOT be started.
2216 This can be used to load and uncompress arbitrary
2217 data.
2218
wdenkc6097192002-11-03 00:24:07 +00002219 initrd_high - restrict positioning of initrd images:
2220 If this variable is not set, initrd images will be
2221 copied to the highest possible address in RAM; this
2222 is usually what you want since it allows for
2223 maximum initrd size. If for some reason you want to
2224 make sure that the initrd image is loaded below the
2225 CFG_BOOTMAPSZ limit, you can set this environment
2226 variable to a value of "no" or "off" or "0".
2227 Alternatively, you can set it to a maximum upper
2228 address to use (U-Boot will still check that it
2229 does not overwrite the U-Boot stack and data).
2230
2231 For instance, when you have a system with 16 MB
wdenk7152b1d2003-09-05 23:19:14 +00002232 RAM, and want to reserve 4 MB from use by Linux,
wdenkc6097192002-11-03 00:24:07 +00002233 you can do this by adding "mem=12M" to the value of
2234 the "bootargs" variable. However, now you must make
wdenk7152b1d2003-09-05 23:19:14 +00002235 sure that the initrd image is placed in the first
wdenkc6097192002-11-03 00:24:07 +00002236 12 MB as well - this can be done with
2237
2238 setenv initrd_high 00c00000
2239
wdenk8bde7f72003-06-27 21:31:46 +00002240 If you set initrd_high to 0xFFFFFFFF, this is an
2241 indication to U-Boot that all addresses are legal
2242 for the Linux kernel, including addresses in flash
2243 memory. In this case U-Boot will NOT COPY the
2244 ramdisk at all. This may be useful to reduce the
2245 boot time on your system, but requires that this
2246 feature is supported by your Linux kernel.
wdenk38b99262003-05-23 23:18:21 +00002247
wdenkc6097192002-11-03 00:24:07 +00002248 ipaddr - IP address; needed for tftpboot command
2249
2250 loadaddr - Default load address for commands like "bootp",
wdenkdc7c9a12003-03-26 06:55:25 +00002251 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00002252
2253 loads_echo - see CONFIG_LOADS_ECHO
2254
2255 serverip - TFTP server IP address; needed for tftpboot command
2256
2257 bootretry - see CONFIG_BOOT_RETRY_TIME
2258
2259 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2260
2261 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2262
2263
2264The following environment variables may be used and automatically
2265updated by the network boot commands ("bootp" and "rarpboot"),
2266depending the information provided by your boot server:
2267
2268 bootfile - see above
2269 dnsip - IP address of your Domain Name Server
stroesefe389a82003-08-28 14:17:32 +00002270 dnsip2 - IP address of your secondary Domain Name Server
wdenkc6097192002-11-03 00:24:07 +00002271 gatewayip - IP address of the Gateway (Router) to use
2272 hostname - Target hostname
2273 ipaddr - see above
2274 netmask - Subnet Mask
2275 rootpath - Pathname of the root filesystem on the NFS server
2276 serverip - see above
2277
2278
2279There are two special Environment Variables:
2280
2281 serial# - contains hardware identification information such
2282 as type string and/or serial number
2283 ethaddr - Ethernet address
2284
2285These variables can be set only once (usually during manufacturing of
2286the board). U-Boot refuses to delete or overwrite these variables
2287once they have been set once.
2288
2289
stroesec1551ea2003-04-04 15:53:41 +00002290Further special Environment Variables:
2291
2292 ver - Contains the U-Boot version string as printed
2293 with the "version" command. This variable is
2294 readonly (see CONFIG_VERSION_VARIABLE).
2295
2296
wdenkc6097192002-11-03 00:24:07 +00002297Please note that changes to some configuration parameters may take
2298only effect after the next boot (yes, that's just like Windoze :-).
2299
2300
wdenkf07771c2003-05-28 08:06:31 +00002301Command Line Parsing:
2302=====================
2303
wdenk7152b1d2003-09-05 23:19:14 +00002304There are two different command line parsers available with U-Boot:
2305the old "simple" one, and the much more powerful "hush" shell:
wdenkf07771c2003-05-28 08:06:31 +00002306
2307Old, simple command line parser:
2308--------------------------------
2309
2310- supports environment variables (through setenv / saveenv commands)
2311- several commands on one line, separated by ';'
2312- variable substitution using "... $(name) ..." syntax
2313- special characters ('$', ';') can be escaped by prefixing with '\',
2314 for example:
2315 setenv bootcmd bootm \$(address)
2316- You can also escape text by enclosing in single apostrophes, for example:
2317 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2318
2319Hush shell:
2320-----------
2321
2322- similar to Bourne shell, with control structures like
2323 if...then...else...fi, for...do...done; while...do...done,
2324 until...do...done, ...
2325- supports environment ("global") variables (through setenv / saveenv
2326 commands) and local shell variables (through standard shell syntax
2327 "name=value"); only environment variables can be used with "run"
2328 command
2329
2330General rules:
2331--------------
2332
2333(1) If a command line (or an environment variable executed by a "run"
2334 command) contains several commands separated by semicolon, and
2335 one of these commands fails, then the remaining commands will be
2336 executed anyway.
2337
2338(2) If you execute several variables with one call to run (i. e.
2339 calling run with a list af variables as arguments), any failing
2340 command will cause "run" to terminate, i. e. the remaining
2341 variables are not executed.
2342
wdenkc6097192002-11-03 00:24:07 +00002343Note for Redundant Ethernet Interfaces:
2344=======================================
2345
wdenk7152b1d2003-09-05 23:19:14 +00002346Some boards come with redundant ethernet interfaces; U-Boot supports
wdenkc6097192002-11-03 00:24:07 +00002347such configurations and is capable of automatic selection of a
wdenk7152b1d2003-09-05 23:19:14 +00002348"working" interface when needed. MAC assignment works as follows:
wdenkc6097192002-11-03 00:24:07 +00002349
2350Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2351MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2352"eth1addr" (=>eth1), "eth2addr", ...
2353
2354If the network interface stores some valid MAC address (for instance
2355in SROM), this is used as default address if there is NO correspon-
2356ding setting in the environment; if the corresponding environment
2357variable is set, this overrides the settings in the card; that means:
2358
2359o If the SROM has a valid MAC address, and there is no address in the
2360 environment, the SROM's address is used.
2361
2362o If there is no valid address in the SROM, and a definition in the
2363 environment exists, then the value from the environment variable is
2364 used.
2365
2366o If both the SROM and the environment contain a MAC address, and
2367 both addresses are the same, this MAC address is used.
2368
2369o If both the SROM and the environment contain a MAC address, and the
2370 addresses differ, the value from the environment is used and a
2371 warning is printed.
2372
2373o If neither SROM nor the environment contain a MAC address, an error
2374 is raised.
2375
2376
wdenkc6097192002-11-03 00:24:07 +00002377Image Formats:
2378==============
2379
2380The "boot" commands of this monitor operate on "image" files which
2381can be basicly anything, preceeded by a special header; see the
2382definitions in include/image.h for details; basicly, the header
2383defines the following image properties:
2384
2385* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2386 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
wdenk7f70e852003-05-20 14:25:27 +00002387 LynxOS, pSOS, QNX, RTEMS, ARTOS;
wdenk1f4bb372003-07-27 00:21:01 +00002388 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
wdenkc6097192002-11-03 00:24:07 +00002389* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
wdenk3d1e8a92003-10-16 12:53:35 +00002390 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2391 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
wdenkc29fdfc2003-08-29 20:57:53 +00002392* Compression Type (uncompressed, gzip, bzip2)
wdenkc6097192002-11-03 00:24:07 +00002393* Load Address
2394* Entry Point
2395* Image Name
2396* Image Timestamp
2397
2398The header is marked by a special Magic Number, and both the header
2399and the data portions of the image are secured against corruption by
2400CRC32 checksums.
2401
2402
2403Linux Support:
2404==============
2405
2406Although U-Boot should support any OS or standalone application
wdenk7152b1d2003-09-05 23:19:14 +00002407easily, the main focus has always been on Linux during the design of
wdenkc6097192002-11-03 00:24:07 +00002408U-Boot.
2409
2410U-Boot includes many features that so far have been part of some
2411special "boot loader" code within the Linux kernel. Also, any
2412"initrd" images to be used are no longer part of one big Linux image;
2413instead, kernel and "initrd" are separate images. This implementation
wdenk7152b1d2003-09-05 23:19:14 +00002414serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00002415
2416- the same features can be used for other OS or standalone
2417 applications (for instance: using compressed images to reduce the
2418 Flash memory footprint)
2419
2420- it becomes much easier to port new Linux kernel versions because
wdenk7152b1d2003-09-05 23:19:14 +00002421 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00002422
2423- the same Linux kernel image can now be used with different "initrd"
2424 images; of course this also means that different kernel images can
2425 be run with the same "initrd". This makes testing easier (you don't
2426 have to build a new "zImage.initrd" Linux image when you just
2427 change a file in your "initrd"). Also, a field-upgrade of the
2428 software is easier now.
2429
2430
2431Linux HOWTO:
2432============
2433
2434Porting Linux to U-Boot based systems:
2435---------------------------------------
2436
2437U-Boot cannot save you from doing all the necessary modifications to
2438configure the Linux device drivers for use with your target hardware
2439(no, we don't intend to provide a full virtual machine interface to
2440Linux :-).
2441
2442But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2443
2444Just make sure your machine specific header file (for instance
2445include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2446Information structure as we define in include/u-boot.h, and make
2447sure that your definition of IMAP_ADDR uses the same value as your
2448U-Boot configuration in CFG_IMMR.
2449
2450
2451Configuring the Linux kernel:
2452-----------------------------
2453
2454No specific requirements for U-Boot. Make sure you have some root
2455device (initial ramdisk, NFS) for your target system.
2456
2457
2458Building a Linux Image:
2459-----------------------
2460
wdenk24ee89b2002-11-03 17:56:27 +00002461With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2462not used. If you use recent kernel source, a new build target
2463"uImage" will exist which automatically builds an image usable by
2464U-Boot. Most older kernels also have support for a "pImage" target,
2465which was introduced for our predecessor project PPCBoot and uses a
2466100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00002467
2468Example:
2469
2470 make TQM850L_config
2471 make oldconfig
2472 make dep
wdenk24ee89b2002-11-03 17:56:27 +00002473 make uImage
wdenkc6097192002-11-03 00:24:07 +00002474
wdenk24ee89b2002-11-03 17:56:27 +00002475The "uImage" build target uses a special tool (in 'tools/mkimage') to
2476encapsulate a compressed Linux kernel image with header information,
2477CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00002478
wdenk24ee89b2002-11-03 17:56:27 +00002479* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00002480
wdenk24ee89b2002-11-03 17:56:27 +00002481* convert the kernel into a raw binary image:
2482
2483 ${CROSS_COMPILE}-objcopy -O binary \
2484 -R .note -R .comment \
2485 -S vmlinux linux.bin
2486
2487* compress the binary image:
2488
2489 gzip -9 linux.bin
2490
2491* package compressed binary image for U-Boot:
2492
2493 mkimage -A ppc -O linux -T kernel -C gzip \
2494 -a 0 -e 0 -n "Linux Kernel Image" \
2495 -d linux.bin.gz uImage
2496
2497
2498The "mkimage" tool can also be used to create ramdisk images for use
2499with U-Boot, either separated from the Linux kernel image, or
2500combined into one file. "mkimage" encapsulates the images with a 64
2501byte header containing information about target architecture,
2502operating system, image type, compression method, entry points, time
2503stamp, CRC32 checksums, etc.
2504
2505"mkimage" can be called in two ways: to verify existing images and
2506print the header information, or to build new images.
2507
2508In the first form (with "-l" option) mkimage lists the information
2509contained in the header of an existing U-Boot image; this includes
wdenkc6097192002-11-03 00:24:07 +00002510checksum verification:
2511
2512 tools/mkimage -l image
2513 -l ==> list image header information
2514
2515The second form (with "-d" option) is used to build a U-Boot image
2516from a "data file" which is used as image payload:
2517
2518 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2519 -n name -d data_file image
2520 -A ==> set architecture to 'arch'
2521 -O ==> set operating system to 'os'
2522 -T ==> set image type to 'type'
2523 -C ==> set compression type 'comp'
2524 -a ==> set load address to 'addr' (hex)
2525 -e ==> set entry point to 'ep' (hex)
2526 -n ==> set image name to 'name'
2527 -d ==> use image data from 'datafile'
2528
2529Right now, all Linux kernels use the same load address (0x00000000),
2530but the entry point address depends on the kernel version:
2531
2532- 2.2.x kernels have the entry point at 0x0000000C,
wdenk24ee89b2002-11-03 17:56:27 +00002533- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00002534
2535So a typical call to build a U-Boot image would read:
2536
wdenk24ee89b2002-11-03 17:56:27 +00002537 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2538 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2539 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2540 > examples/uImage.TQM850L
2541 Image Name: 2.4.4 kernel for TQM850L
wdenkc6097192002-11-03 00:24:07 +00002542 Created: Wed Jul 19 02:34:59 2000
2543 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2544 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2545 Load Address: 0x00000000
wdenk24ee89b2002-11-03 17:56:27 +00002546 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002547
2548To verify the contents of the image (or check for corruption):
2549
wdenk24ee89b2002-11-03 17:56:27 +00002550 -> tools/mkimage -l examples/uImage.TQM850L
2551 Image Name: 2.4.4 kernel for TQM850L
wdenkc6097192002-11-03 00:24:07 +00002552 Created: Wed Jul 19 02:34:59 2000
2553 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2554 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2555 Load Address: 0x00000000
wdenk24ee89b2002-11-03 17:56:27 +00002556 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002557
2558NOTE: for embedded systems where boot time is critical you can trade
2559speed for memory and install an UNCOMPRESSED image instead: this
2560needs more space in Flash, but boots much faster since it does not
2561need to be uncompressed:
2562
wdenk24ee89b2002-11-03 17:56:27 +00002563 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2564 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2565 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2566 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2567 > examples/uImage.TQM850L-uncompressed
2568 Image Name: 2.4.4 kernel for TQM850L
wdenkc6097192002-11-03 00:24:07 +00002569 Created: Wed Jul 19 02:34:59 2000
2570 Image Type: PowerPC Linux Kernel Image (uncompressed)
2571 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2572 Load Address: 0x00000000
wdenk24ee89b2002-11-03 17:56:27 +00002573 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002574
2575
2576Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2577when your kernel is intended to use an initial ramdisk:
2578
2579 -> tools/mkimage -n 'Simple Ramdisk Image' \
2580 > -A ppc -O linux -T ramdisk -C gzip \
2581 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2582 Image Name: Simple Ramdisk Image
2583 Created: Wed Jan 12 14:01:50 2000
2584 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2585 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2586 Load Address: 0x00000000
2587 Entry Point: 0x00000000
2588
2589
2590Installing a Linux Image:
2591-------------------------
2592
2593To downloading a U-Boot image over the serial (console) interface,
2594you must convert the image to S-Record format:
2595
2596 objcopy -I binary -O srec examples/image examples/image.srec
2597
2598The 'objcopy' does not understand the information in the U-Boot
2599image header, so the resulting S-Record file will be relative to
2600address 0x00000000. To load it to a given address, you need to
2601specify the target address as 'offset' parameter with the 'loads'
2602command.
2603
2604Example: install the image to address 0x40100000 (which on the
2605TQM8xxL is in the first Flash bank):
2606
2607 => erase 40100000 401FFFFF
2608
2609 .......... done
2610 Erased 8 sectors
2611
2612 => loads 40100000
2613 ## Ready for S-Record download ...
2614 ~>examples/image.srec
2615 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2616 ...
2617 15989 15990 15991 15992
2618 [file transfer complete]
2619 [connected]
2620 ## Start Addr = 0x00000000
2621
2622
2623You can check the success of the download using the 'iminfo' command;
2624this includes a checksum verification so you can be sure no data
2625corruption happened:
2626
2627 => imi 40100000
2628
2629 ## Checking Image at 40100000 ...
2630 Image Name: 2.2.13 for initrd on TQM850L
2631 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2632 Data Size: 335725 Bytes = 327 kB = 0 MB
2633 Load Address: 00000000
2634 Entry Point: 0000000c
2635 Verifying Checksum ... OK
2636
2637
wdenkc6097192002-11-03 00:24:07 +00002638Boot Linux:
2639-----------
2640
2641The "bootm" command is used to boot an application that is stored in
2642memory (RAM or Flash). In case of a Linux kernel image, the contents
2643of the "bootargs" environment variable is passed to the kernel as
2644parameters. You can check and modify this variable using the
2645"printenv" and "setenv" commands:
2646
2647
2648 => printenv bootargs
2649 bootargs=root=/dev/ram
2650
2651 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2652
2653 => printenv bootargs
2654 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2655
2656 => bootm 40020000
2657 ## Booting Linux kernel at 40020000 ...
2658 Image Name: 2.2.13 for NFS on TQM850L
2659 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2660 Data Size: 381681 Bytes = 372 kB = 0 MB
2661 Load Address: 00000000
2662 Entry Point: 0000000c
2663 Verifying Checksum ... OK
2664 Uncompressing Kernel Image ... OK
2665 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
2666 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2667 time_init: decrementer frequency = 187500000/60
2668 Calibrating delay loop... 49.77 BogoMIPS
2669 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2670 ...
2671
2672If you want to boot a Linux kernel with initial ram disk, you pass
wdenk7152b1d2003-09-05 23:19:14 +00002673the memory addresses of both the kernel and the initrd image (PPBCOOT
wdenkc6097192002-11-03 00:24:07 +00002674format!) to the "bootm" command:
2675
2676 => imi 40100000 40200000
2677
2678 ## Checking Image at 40100000 ...
2679 Image Name: 2.2.13 for initrd on TQM850L
2680 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2681 Data Size: 335725 Bytes = 327 kB = 0 MB
2682 Load Address: 00000000
2683 Entry Point: 0000000c
2684 Verifying Checksum ... OK
2685
2686 ## Checking Image at 40200000 ...
2687 Image Name: Simple Ramdisk Image
2688 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2689 Data Size: 566530 Bytes = 553 kB = 0 MB
2690 Load Address: 00000000
2691 Entry Point: 00000000
2692 Verifying Checksum ... OK
2693
2694 => bootm 40100000 40200000
2695 ## Booting Linux kernel at 40100000 ...
2696 Image Name: 2.2.13 for initrd on TQM850L
2697 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2698 Data Size: 335725 Bytes = 327 kB = 0 MB
2699 Load Address: 00000000
2700 Entry Point: 0000000c
2701 Verifying Checksum ... OK
2702 Uncompressing Kernel Image ... OK
2703 ## Loading RAMDisk Image at 40200000 ...
2704 Image Name: Simple Ramdisk Image
2705 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2706 Data Size: 566530 Bytes = 553 kB = 0 MB
2707 Load Address: 00000000
2708 Entry Point: 00000000
2709 Verifying Checksum ... OK
2710 Loading Ramdisk ... OK
2711 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
2712 Boot arguments: root=/dev/ram
2713 time_init: decrementer frequency = 187500000/60
2714 Calibrating delay loop... 49.77 BogoMIPS
2715 ...
2716 RAMDISK: Compressed image found at block 0
2717 VFS: Mounted root (ext2 filesystem).
2718
2719 bash#
2720
wdenk6069ff22003-02-28 00:49:47 +00002721More About U-Boot Image Types:
2722------------------------------
2723
2724U-Boot supports the following image types:
2725
2726 "Standalone Programs" are directly runnable in the environment
wdenk8bde7f72003-06-27 21:31:46 +00002727 provided by U-Boot; it is expected that (if they behave
2728 well) you can continue to work in U-Boot after return from
2729 the Standalone Program.
wdenk6069ff22003-02-28 00:49:47 +00002730 "OS Kernel Images" are usually images of some Embedded OS which
wdenk8bde7f72003-06-27 21:31:46 +00002731 will take over control completely. Usually these programs
2732 will install their own set of exception handlers, device
2733 drivers, set up the MMU, etc. - this means, that you cannot
2734 expect to re-enter U-Boot except by resetting the CPU.
wdenk6069ff22003-02-28 00:49:47 +00002735 "RAMDisk Images" are more or less just data blocks, and their
wdenk8bde7f72003-06-27 21:31:46 +00002736 parameters (address, size) are passed to an OS kernel that is
2737 being started.
wdenk6069ff22003-02-28 00:49:47 +00002738 "Multi-File Images" contain several images, typically an OS
wdenk8bde7f72003-06-27 21:31:46 +00002739 (Linux) kernel image and one or more data images like
2740 RAMDisks. This construct is useful for instance when you want
2741 to boot over the network using BOOTP etc., where the boot
2742 server provides just a single image file, but you want to get
2743 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00002744
wdenk8bde7f72003-06-27 21:31:46 +00002745 "Multi-File Images" start with a list of image sizes, each
2746 image size (in bytes) specified by an "uint32_t" in network
2747 byte order. This list is terminated by an "(uint32_t)0".
2748 Immediately after the terminating 0 follow the images, one by
2749 one, all aligned on "uint32_t" boundaries (size rounded up to
2750 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00002751
wdenk6069ff22003-02-28 00:49:47 +00002752 "Firmware Images" are binary images containing firmware (like
wdenk8bde7f72003-06-27 21:31:46 +00002753 U-Boot or FPGA images) which usually will be programmed to
2754 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00002755
wdenk6069ff22003-02-28 00:49:47 +00002756 "Script files" are command sequences that will be executed by
wdenk8bde7f72003-06-27 21:31:46 +00002757 U-Boot's command interpreter; this feature is especially
2758 useful when you configure U-Boot to use a real shell (hush)
2759 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00002760
wdenkc6097192002-11-03 00:24:07 +00002761
2762Standalone HOWTO:
2763=================
2764
2765One of the features of U-Boot is that you can dynamically load and
2766run "standalone" applications, which can use some resources of
2767U-Boot like console I/O functions or interrupt services.
2768
2769Two simple examples are included with the sources:
2770
2771"Hello World" Demo:
2772-------------------
2773
2774'examples/hello_world.c' contains a small "Hello World" Demo
2775application; it is automatically compiled when you build U-Boot.
2776It's configured to run at address 0x00040004, so you can play with it
2777like that:
2778
2779 => loads
2780 ## Ready for S-Record download ...
2781 ~>examples/hello_world.srec
2782 1 2 3 4 5 6 7 8 9 10 11 ...
2783 [file transfer complete]
2784 [connected]
2785 ## Start Addr = 0x00040004
2786
2787 => go 40004 Hello World! This is a test.
2788 ## Starting application at 0x00040004 ...
2789 Hello World
2790 argc = 7
2791 argv[0] = "40004"
2792 argv[1] = "Hello"
2793 argv[2] = "World!"
2794 argv[3] = "This"
2795 argv[4] = "is"
2796 argv[5] = "a"
2797 argv[6] = "test."
2798 argv[7] = "<NULL>"
2799 Hit any key to exit ...
2800
2801 ## Application terminated, rc = 0x0
2802
2803Another example, which demonstrates how to register a CPM interrupt
2804handler with the U-Boot code, can be found in 'examples/timer.c'.
2805Here, a CPM timer is set up to generate an interrupt every second.
2806The interrupt service routine is trivial, just printing a '.'
2807character, but this is just a demo program. The application can be
2808controlled by the following keys:
2809
2810 ? - print current values og the CPM Timer registers
2811 b - enable interrupts and start timer
2812 e - stop timer and disable interrupts
2813 q - quit application
2814
2815 => loads
2816 ## Ready for S-Record download ...
2817 ~>examples/timer.srec
2818 1 2 3 4 5 6 7 8 9 10 11 ...
2819 [file transfer complete]
2820 [connected]
2821 ## Start Addr = 0x00040004
2822
2823 => go 40004
2824 ## Starting application at 0x00040004 ...
2825 TIMERS=0xfff00980
2826 Using timer 1
2827 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2828
2829Hit 'b':
2830 [q, b, e, ?] Set interval 1000000 us
2831 Enabling timer
2832Hit '?':
2833 [q, b, e, ?] ........
2834 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2835Hit '?':
2836 [q, b, e, ?] .
2837 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2838Hit '?':
2839 [q, b, e, ?] .
2840 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2841Hit '?':
2842 [q, b, e, ?] .
2843 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2844Hit 'e':
2845 [q, b, e, ?] ...Stopping timer
2846Hit 'q':
2847 [q, b, e, ?] ## Application terminated, rc = 0x0
2848
2849
wdenk85ec0bc2003-03-31 16:34:49 +00002850Minicom warning:
2851================
2852
wdenk7152b1d2003-09-05 23:19:14 +00002853Over time, many people have reported problems when trying to use the
wdenkf07771c2003-05-28 08:06:31 +00002854"minicom" terminal emulation program for serial download. I (wd)
2855consider minicom to be broken, and recommend not to use it. Under
2856Unix, I recommend to use C-Kermit for general purpose use (and
wdenk85ec0bc2003-03-31 16:34:49 +00002857especially for kermit binary protocol download ("loadb" command), and
2858use "cu" for S-Record download ("loads" command).
2859
wdenk52f52c12003-06-19 23:04:19 +00002860Nevertheless, if you absolutely want to use it try adding this
2861configuration to your "File transfer protocols" section:
2862
2863 Name Program Name U/D FullScr IO-Red. Multi
2864 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2865 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2866
2867
wdenkc6097192002-11-03 00:24:07 +00002868NetBSD Notes:
2869=============
2870
2871Starting at version 0.9.2, U-Boot supports NetBSD both as host
2872(build U-Boot) and target system (boots NetBSD/mpc8xx).
2873
2874Building requires a cross environment; it is known to work on
2875NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2876need gmake since the Makefiles are not compatible with BSD make).
2877Note that the cross-powerpc package does not install include files;
2878attempting to build U-Boot will fail because <machine/ansi.h> is
2879missing. This file has to be installed and patched manually:
2880
2881 # cd /usr/pkg/cross/powerpc-netbsd/include
2882 # mkdir powerpc
2883 # ln -s powerpc machine
2884 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2885 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2886
2887Native builds *don't* work due to incompatibilities between native
2888and U-Boot include files.
2889
2890Booting assumes that (the first part of) the image booted is a
2891stage-2 loader which in turn loads and then invokes the kernel
2892proper. Loader sources will eventually appear in the NetBSD source
2893tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2894meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2895details.
2896
2897
2898Implementation Internals:
2899=========================
2900
2901The following is not intended to be a complete description of every
2902implementation detail. However, it should help to understand the
2903inner workings of U-Boot and make it easier to port it to custom
2904hardware.
2905
2906
2907Initial Stack, Global Data:
2908---------------------------
2909
2910The implementation of U-Boot is complicated by the fact that U-Boot
2911starts running out of ROM (flash memory), usually without access to
2912system RAM (because the memory controller is not initialized yet).
2913This means that we don't have writable Data or BSS segments, and BSS
2914is not initialized as zero. To be able to get a C environment working
2915at all, we have to allocate at least a minimal stack. Implementation
2916options for this are defined and restricted by the CPU used: Some CPU
2917models provide on-chip memory (like the IMMR area on MPC8xx and
2918MPC826x processors), on others (parts of) the data cache can be
2919locked as (mis-) used as memory, etc.
2920
wdenk7152b1d2003-09-05 23:19:14 +00002921 Chris Hallinan posted a good summary of these issues to the
wdenk43d96162003-03-06 00:02:04 +00002922 u-boot-users mailing list:
2923
2924 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2925 From: "Chris Hallinan" <clh@net1plus.com>
2926 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2927 ...
2928
2929 Correct me if I'm wrong, folks, but the way I understand it
2930 is this: Using DCACHE as initial RAM for Stack, etc, does not
2931 require any physical RAM backing up the cache. The cleverness
2932 is that the cache is being used as a temporary supply of
2933 necessary storage before the SDRAM controller is setup. It's
2934 beyond the scope of this list to expain the details, but you
2935 can see how this works by studying the cache architecture and
2936 operation in the architecture and processor-specific manuals.
2937
2938 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2939 is another option for the system designer to use as an
2940 initial stack/ram area prior to SDRAM being available. Either
2941 option should work for you. Using CS 4 should be fine if your
2942 board designers haven't used it for something that would
2943 cause you grief during the initial boot! It is frequently not
2944 used.
2945
2946 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2947 with your processor/board/system design. The default value
2948 you will find in any recent u-boot distribution in
2949 Walnut405.h should work for you. I'd set it to a value larger
2950 than your SDRAM module. If you have a 64MB SDRAM module, set
2951 it above 400_0000. Just make sure your board has no resources
2952 that are supposed to respond to that address! That code in
2953 start.S has been around a while and should work as is when
2954 you get the config right.
2955
2956 -Chris Hallinan
2957 DS4.COM, Inc.
2958
wdenkc6097192002-11-03 00:24:07 +00002959It is essential to remember this, since it has some impact on the C
2960code for the initialization procedures:
2961
2962* Initialized global data (data segment) is read-only. Do not attempt
2963 to write it.
2964
2965* Do not use any unitialized global data (or implicitely initialized
2966 as zero data - BSS segment) at all - this is undefined, initiali-
wdenk7152b1d2003-09-05 23:19:14 +00002967 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00002968
wdenk7152b1d2003-09-05 23:19:14 +00002969* Stack space is very limited. Avoid big data buffers or things like
wdenkc6097192002-11-03 00:24:07 +00002970 that.
2971
2972Having only the stack as writable memory limits means we cannot use
2973normal global data to share information beween the code. But it
2974turned out that the implementation of U-Boot can be greatly
2975simplified by making a global data structure (gd_t) available to all
2976functions. We could pass a pointer to this data as argument to _all_
2977functions, but this would bloat the code. Instead we use a feature of
2978the GCC compiler (Global Register Variables) to share the data: we
2979place a pointer (gd) to the global data into a register which we
2980reserve for this purpose.
2981
wdenk7152b1d2003-09-05 23:19:14 +00002982When choosing a register for such a purpose we are restricted by the
wdenkc6097192002-11-03 00:24:07 +00002983relevant (E)ABI specifications for the current architecture, and by
2984GCC's implementation.
2985
2986For PowerPC, the following registers have specific use:
2987 R1: stack pointer
2988 R2: TOC pointer
2989 R3-R4: parameter passing and return values
2990 R5-R10: parameter passing
2991 R13: small data area pointer
2992 R30: GOT pointer
2993 R31: frame pointer
2994
2995 (U-Boot also uses R14 as internal GOT pointer.)
2996
2997 ==> U-Boot will use R29 to hold a pointer to the global data
2998
2999 Note: on PPC, we could use a static initializer (since the
3000 address of the global data structure is known at compile time),
3001 but it turned out that reserving a register results in somewhat
3002 smaller code - although the code savings are not that big (on
3003 average for all boards 752 bytes for the whole U-Boot image,
3004 624 text + 127 data).
3005
3006On ARM, the following registers are used:
3007
3008 R0: function argument word/integer result
3009 R1-R3: function argument word
3010 R9: GOT pointer
3011 R10: stack limit (used only if stack checking if enabled)
3012 R11: argument (frame) pointer
3013 R12: temporary workspace
3014 R13: stack pointer
3015 R14: link register
3016 R15: program counter
3017
3018 ==> U-Boot will use R8 to hold a pointer to the global data
3019
3020
wdenkc6097192002-11-03 00:24:07 +00003021Memory Management:
3022------------------
3023
3024U-Boot runs in system state and uses physical addresses, i.e. the
3025MMU is not used either for address mapping nor for memory protection.
3026
3027The available memory is mapped to fixed addresses using the memory
3028controller. In this process, a contiguous block is formed for each
3029memory type (Flash, SDRAM, SRAM), even when it consists of several
3030physical memory banks.
3031
3032U-Boot is installed in the first 128 kB of the first Flash bank (on
3033TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3034booting and sizing and initializing DRAM, the code relocates itself
3035to the upper end of DRAM. Immediately below the U-Boot code some
3036memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3037configuration setting]. Below that, a structure with global Board
3038Info data is placed, followed by the stack (growing downward).
3039
3040Additionally, some exception handler code is copied to the low 8 kB
3041of DRAM (0x00000000 ... 0x00001FFF).
3042
3043So a typical memory configuration with 16 MB of DRAM could look like
3044this:
3045
3046 0x0000 0000 Exception Vector code
3047 :
3048 0x0000 1FFF
3049 0x0000 2000 Free for Application Use
3050 :
3051 :
3052
3053 :
3054 :
3055 0x00FB FF20 Monitor Stack (Growing downward)
3056 0x00FB FFAC Board Info Data and permanent copy of global data
3057 0x00FC 0000 Malloc Arena
3058 :
3059 0x00FD FFFF
3060 0x00FE 0000 RAM Copy of Monitor Code
3061 ... eventually: LCD or video framebuffer
3062 ... eventually: pRAM (Protected RAM - unchanged by reset)
3063 0x00FF FFFF [End of RAM]
3064
3065
3066System Initialization:
3067----------------------
3068
3069In the reset configuration, U-Boot starts at the reset entry point
3070(on most PowerPC systens at address 0x00000100). Because of the reset
3071configuration for CS0# this is a mirror of the onboard Flash memory.
wdenk7152b1d2003-09-05 23:19:14 +00003072To be able to re-map memory U-Boot then jumps to its link address.
wdenkc6097192002-11-03 00:24:07 +00003073To be able to implement the initialization code in C, a (small!)
3074initial stack is set up in the internal Dual Ported RAM (in case CPUs
3075which provide such a feature like MPC8xx or MPC8260), or in a locked
3076part of the data cache. After that, U-Boot initializes the CPU core,
3077the caches and the SIU.
3078
3079Next, all (potentially) available memory banks are mapped using a
3080preliminary mapping. For example, we put them on 512 MB boundaries
3081(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3082on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3083programmed for SDRAM access. Using the temporary configuration, a
3084simple memory test is run that determines the size of the SDRAM
3085banks.
3086
3087When there is more than one SDRAM bank, and the banks are of
wdenk7152b1d2003-09-05 23:19:14 +00003088different size, the largest is mapped first. For equal size, the first
wdenkc6097192002-11-03 00:24:07 +00003089bank (CS2#) is mapped first. The first mapping is always for address
30900x00000000, with any additional banks following immediately to create
3091contiguous memory starting from 0.
3092
3093Then, the monitor installs itself at the upper end of the SDRAM area
3094and allocates memory for use by malloc() and for the global Board
3095Info data; also, the exception vector code is copied to the low RAM
3096pages, and the final stack is set up.
3097
3098Only after this relocation will you have a "normal" C environment;
3099until that you are restricted in several ways, mostly because you are
3100running from ROM, and because the code will have to be relocated to a
3101new address in RAM.
3102
3103
3104U-Boot Porting Guide:
3105----------------------
3106
3107[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
wdenk6aff3112002-12-17 01:51:00 +00003108list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00003109
3110
3111int main (int argc, char *argv[])
3112{
3113 sighandler_t no_more_time;
3114
3115 signal (SIGALRM, no_more_time);
3116 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3117
3118 if (available_money > available_manpower) {
3119 pay consultant to port U-Boot;
3120 return 0;
3121 }
3122
3123 Download latest U-Boot source;
3124
wdenk6aff3112002-12-17 01:51:00 +00003125 Subscribe to u-boot-users mailing list;
3126
wdenkc6097192002-11-03 00:24:07 +00003127 if (clueless) {
3128 email ("Hi, I am new to U-Boot, how do I get started?");
3129 }
3130
3131 while (learning) {
3132 Read the README file in the top level directory;
wdenk7cb22f92003-12-27 19:24:54 +00003133 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
wdenkc6097192002-11-03 00:24:07 +00003134 Read the source, Luke;
3135 }
3136
3137 if (available_money > toLocalCurrency ($2500)) {
3138 Buy a BDI2000;
3139 } else {
3140 Add a lot of aggravation and time;
3141 }
3142
3143 Create your own board support subdirectory;
3144
wdenk6aff3112002-12-17 01:51:00 +00003145 Create your own board config file;
3146
wdenkc6097192002-11-03 00:24:07 +00003147 while (!running) {
3148 do {
3149 Add / modify source code;
3150 } until (compiles);
3151 Debug;
3152 if (clueless)
3153 email ("Hi, I am having problems...");
3154 }
3155 Send patch file to Wolfgang;
3156
3157 return 0;
3158}
3159
3160void no_more_time (int sig)
3161{
3162 hire_a_guru();
3163}
3164
3165
wdenkc6097192002-11-03 00:24:07 +00003166Coding Standards:
3167-----------------
3168
3169All contributions to U-Boot should conform to the Linux kernel
3170coding style; see the file "Documentation/CodingStyle" in your Linux
3171kernel source directory.
3172
3173Please note that U-Boot is implemented in C (and to some small parts
3174in Assembler); no C++ is used, so please do not use C++ style
3175comments (//) in your code.
3176
wdenkc178d3d2004-01-24 20:25:54 +00003177Please also stick to the following formatting rules:
wdenk180d3f72004-01-04 16:28:35 +00003178- remove any trailing white space
3179- use TAB characters for indentation, not spaces
3180- make sure NOT to use DOS '\r\n' line feeds
3181- do not add more than 2 empty lines to source files
3182- do not add trailing empty lines to source files
3183
wdenkc6097192002-11-03 00:24:07 +00003184Submissions which do not conform to the standards may be returned
3185with a request to reformat the changes.
3186
3187
3188Submitting Patches:
3189-------------------
3190
3191Since the number of patches for U-Boot is growing, we need to
3192establish some rules. Submissions which do not conform to these rules
3193may be rejected, even when they contain important and valuable stuff.
3194
3195
3196When you send a patch, please include the following information with
3197it:
3198
3199* For bug fixes: a description of the bug and how your patch fixes
3200 this bug. Please try to include a way of demonstrating that the
3201 patch actually fixes something.
3202
3203* For new features: a description of the feature and your
3204 implementation.
3205
3206* A CHANGELOG entry as plaintext (separate from the patch)
3207
3208* For major contributions, your entry to the CREDITS file
3209
3210* When you add support for a new board, don't forget to add this
3211 board to the MAKEALL script, too.
3212
3213* If your patch adds new configuration options, don't forget to
3214 document these in the README file.
3215
3216* The patch itself. If you are accessing the CVS repository use "cvs
3217 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3218 version of diff does not support these options, then get the latest
3219 version of GNU diff.
3220
wdenk6dff5522003-07-15 07:45:49 +00003221 The current directory when running this command shall be the top
3222 level directory of the U-Boot source tree, or it's parent directory
3223 (i. e. please make sure that your patch includes sufficient
3224 directory information for the affected files).
3225
wdenkc6097192002-11-03 00:24:07 +00003226 We accept patches as plain text, MIME attachments or as uuencoded
3227 gzipped text.
3228
wdenk52f52c12003-06-19 23:04:19 +00003229* If one logical set of modifications affects or creates several
3230 files, all these changes shall be submitted in a SINGLE patch file.
3231
3232* Changesets that contain different, unrelated modifications shall be
3233 submitted as SEPARATE patches, one patch per changeset.
wdenk8bde7f72003-06-27 21:31:46 +00003234
wdenk52f52c12003-06-19 23:04:19 +00003235
wdenkc6097192002-11-03 00:24:07 +00003236Notes:
3237
3238* Before sending the patch, run the MAKEALL script on your patched
3239 source tree and make sure that no errors or warnings are reported
3240 for any of the boards.
3241
3242* Keep your modifications to the necessary minimum: A patch
3243 containing several unrelated changes or arbitrary reformats will be
3244 returned with a request to re-formatting / split it.
3245
3246* If you modify existing code, make sure that your new code does not
3247 add to the memory footprint of the code ;-) Small is beautiful!
3248 When adding new features, these should compile conditionally only
3249 (using #ifdef), and the resulting code with the new feature
3250 disabled must not need more memory than the old code without your
3251 modification.