xref: /openbmc/u-boot/README (revision c40b29568232761e33400e58be86b15a167d3422)
1c609719bSwdenk#
23a473b2aSwdenk# (C) Copyright 2000 - 2004
3c609719bSwdenk# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4c609719bSwdenk#
5c609719bSwdenk# See file CREDITS for list of people who contributed to this
6c609719bSwdenk# project.
7c609719bSwdenk#
8c609719bSwdenk# This program is free software; you can redistribute it and/or
9c609719bSwdenk# modify it under the terms of the GNU General Public License as
10c609719bSwdenk# published by the Free Software Foundation; either version 2 of
11c609719bSwdenk# the License, or (at your option) any later version.
12c609719bSwdenk#
13c609719bSwdenk# This program is distributed in the hope that it will be useful,
14c609719bSwdenk# but WITHOUT ANY WARRANTY; without even the implied warranty of
15c609719bSwdenk# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
16c609719bSwdenk# GNU General Public License for more details.
17c609719bSwdenk#
18c609719bSwdenk# You should have received a copy of the GNU General Public License
19c609719bSwdenk# along with this program; if not, write to the Free Software
20c609719bSwdenk# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21c609719bSwdenk# MA 02111-1307 USA
22c609719bSwdenk#
23c609719bSwdenk
24c609719bSwdenkSummary:
25c609719bSwdenk========
26c609719bSwdenk
2724ee89b9SwdenkThis directory contains the source code for U-Boot, a boot loader for
2824ee89b9SwdenkEmbedded boards based on PowerPC and ARM processors, which can be
2924ee89b9Swdenkinstalled in a boot ROM and used to initialize and test the hardware
3024ee89b9Swdenkor to download and run application code.
31c609719bSwdenk
32c609719bSwdenkThe development of U-Boot is closely related to Linux: some parts of
3324ee89b9Swdenkthe source code originate in the Linux source tree, we have some
3424ee89b9Swdenkheader files in common, and special provision has been made to
35c609719bSwdenksupport booting of Linux images.
36c609719bSwdenk
37c609719bSwdenkSome attention has been paid to make this software easily
38c609719bSwdenkconfigurable and extendable. For instance, all monitor commands are
39c609719bSwdenkimplemented with the same call interface, so that it's very easy to
40c609719bSwdenkadd new commands. Also, instead of permanently adding rarely used
41c609719bSwdenkcode (for instance hardware test utilities) to the monitor, you can
42c609719bSwdenkload and run it dynamically.
43c609719bSwdenk
44c609719bSwdenk
45c609719bSwdenkStatus:
46c609719bSwdenk=======
47c609719bSwdenk
48c609719bSwdenkIn general, all boards for which a configuration option exists in the
49c609719bSwdenkMakefile have been tested to some extent and can be considered
50c609719bSwdenk"working". In fact, many of them are used in production systems.
51c609719bSwdenk
52c609719bSwdenkIn case of problems see the CHANGELOG and CREDITS files to find out
53c609719bSwdenkwho contributed the specific port.
54c609719bSwdenk
55c609719bSwdenk
56c609719bSwdenkWhere to get help:
57c609719bSwdenk==================
58c609719bSwdenk
59c609719bSwdenkIn case you have questions about, problems with or contributions for
60c609719bSwdenkU-Boot you should send a message to the U-Boot mailing list at
61c609719bSwdenk<u-boot-users@lists.sourceforge.net>. There is also an archive of
62c609719bSwdenkprevious traffic on the mailing list - please search the archive
63c609719bSwdenkbefore asking FAQ's. Please see
64c609719bSwdenkhttp://lists.sourceforge.net/lists/listinfo/u-boot-users/
65c609719bSwdenk
66c609719bSwdenk
67c609719bSwdenkWhere we come from:
68c609719bSwdenk===================
69c609719bSwdenk
70c609719bSwdenk- start from 8xxrom sources
7124ee89b9Swdenk- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
72c609719bSwdenk- clean up code
73c609719bSwdenk- make it easier to add custom boards
74c609719bSwdenk- make it possible to add other [PowerPC] CPUs
75c609719bSwdenk- extend functions, especially:
76c609719bSwdenk  * Provide extended interface to Linux boot loader
77c609719bSwdenk  * S-Record download
78c609719bSwdenk  * network boot
79c609719bSwdenk  * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
8024ee89b9Swdenk- create ARMBoot project (http://sourceforge.net/projects/armboot)
81c609719bSwdenk- add other CPU families (starting with ARM)
8224ee89b9Swdenk- create U-Boot project (http://sourceforge.net/projects/u-boot)
8324ee89b9Swdenk
8424ee89b9Swdenk
8524ee89b9SwdenkNames and Spelling:
8624ee89b9Swdenk===================
8724ee89b9Swdenk
8824ee89b9SwdenkThe "official" name of this project is "Das U-Boot". The spelling
8924ee89b9Swdenk"U-Boot" shall be used in all written text (documentation, comments
9024ee89b9Swdenkin source files etc.). Example:
9124ee89b9Swdenk
9224ee89b9Swdenk	This is the README file for the U-Boot project.
9324ee89b9Swdenk
9424ee89b9SwdenkFile names etc. shall be based on the string "u-boot". Examples:
9524ee89b9Swdenk
9624ee89b9Swdenk	include/asm-ppc/u-boot.h
9724ee89b9Swdenk
9824ee89b9Swdenk	#include <asm/u-boot.h>
9924ee89b9Swdenk
10024ee89b9SwdenkVariable names, preprocessor constants etc. shall be either based on
10124ee89b9Swdenkthe string "u_boot" or on "U_BOOT". Example:
10224ee89b9Swdenk
10324ee89b9Swdenk	U_BOOT_VERSION		u_boot_logo
10424ee89b9Swdenk	IH_OS_U_BOOT		u_boot_hush_start
105c609719bSwdenk
106c609719bSwdenk
10793f19cc0SwdenkVersioning:
10893f19cc0Swdenk===========
10993f19cc0Swdenk
11093f19cc0SwdenkU-Boot uses a 3 level version number containing a version, a
11193f19cc0Swdenksub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
11293f19cc0Swdenksub-version "34", and patchlevel "4".
11393f19cc0Swdenk
11493f19cc0SwdenkThe patchlevel is used to indicate certain stages of development
11593f19cc0Swdenkbetween released versions, i. e. officially released versions of
11693f19cc0SwdenkU-Boot will always have a patchlevel of "0".
11793f19cc0Swdenk
11893f19cc0Swdenk
119c609719bSwdenkDirectory Hierarchy:
120c609719bSwdenk====================
121c609719bSwdenk
1227152b1d0Swdenk- board		Board dependent files
1237152b1d0Swdenk- common	Misc architecture independent functions
124c609719bSwdenk- cpu		CPU specific files
12511dadd54Swdenk  - 74xx_7xx	Files specific to Motorola MPC74xx and 7xx CPUs
12611dadd54Swdenk  - arm720t	Files specific to ARM 720 CPUs
12711dadd54Swdenk  - arm920t	Files specific to ARM 920 CPUs
12811dadd54Swdenk  - arm925t	Files specific to ARM 925 CPUs
12911dadd54Swdenk  - arm926ejs	Files specific to ARM 926 CPUs
13011dadd54Swdenk  - at91rm9200	Files specific to Atmel AT91RM9200 CPUs
13111dadd54Swdenk  - i386	Files specific to i386 CPUs
13211dadd54Swdenk  - ixp		Files specific to Intel XScale IXP CPUs
13311dadd54Swdenk  - mcf52x2	Files specific to Motorola ColdFire MCF52x2 CPUs
13411dadd54Swdenk  - mips	Files specific to MIPS CPUs
13511dadd54Swdenk  - mpc5xx	Files specific to Motorola MPC5xx  CPUs
13611dadd54Swdenk  - mpc5xxx	Files specific to Motorola MPC5xxx CPUs
13711dadd54Swdenk  - mpc8xx	Files specific to Motorola MPC8xx  CPUs
13811dadd54Swdenk  - mpc824x	Files specific to Motorola MPC824x CPUs
13911dadd54Swdenk  - mpc8260	Files specific to Motorola MPC8260 CPUs
14011dadd54Swdenk  - mpc85xx	Files specific to Motorola MPC85xx CPUs
14111dadd54Swdenk  - nios	Files specific to Altera NIOS CPUs
14211dadd54Swdenk  - ppc4xx	Files specific to IBM PowerPC 4xx CPUs
14311dadd54Swdenk  - pxa		Files specific to Intel XScale PXA CPUs
14411dadd54Swdenk  - s3c44b0	Files specific to Samsung S3C44B0 CPUs
14511dadd54Swdenk  - sa1100	Files specific to Intel StrongARM SA1100 CPUs
146c609719bSwdenk- disk		Code for disk drive partition handling
147c609719bSwdenk- doc		Documentation (don't expect too much)
1487152b1d0Swdenk- drivers	Commonly used device drivers
149c609719bSwdenk- dtt		Digital Thermometer and Thermostat drivers
150c609719bSwdenk- examples	Example code for standalone applications, etc.
151c609719bSwdenk- include	Header Files
15211dadd54Swdenk- lib_arm	Files generic to ARM	 architecture
15311dadd54Swdenk- lib_generic	Files generic to all	 architectures
15411dadd54Swdenk- lib_i386	Files generic to i386	 architecture
15511dadd54Swdenk- lib_m68k	Files generic to m68k	 architecture
15611dadd54Swdenk- lib_mips	Files generic to MIPS	 architecture
15711dadd54Swdenk- lib_nios	Files generic to NIOS	 architecture
15811dadd54Swdenk- lib_ppc	Files generic to PowerPC architecture
159c609719bSwdenk- net		Networking code
160c609719bSwdenk- post		Power On Self Test
161c609719bSwdenk- rtc		Real Time Clock drivers
162c609719bSwdenk- tools		Tools to build S-Record or U-Boot images, etc.
163c609719bSwdenk
164c609719bSwdenkSoftware Configuration:
165c609719bSwdenk=======================
166c609719bSwdenk
167c609719bSwdenkConfiguration is usually done using C preprocessor defines; the
168c609719bSwdenkrationale behind that is to avoid dead code whenever possible.
169c609719bSwdenk
170c609719bSwdenkThere are two classes of configuration variables:
171c609719bSwdenk
172c609719bSwdenk* Configuration _OPTIONS_:
173c609719bSwdenk  These are selectable by the user and have names beginning with
174c609719bSwdenk  "CONFIG_".
175c609719bSwdenk
176c609719bSwdenk* Configuration _SETTINGS_:
177c609719bSwdenk  These depend on the hardware etc. and should not be meddled with if
178c609719bSwdenk  you don't know what you're doing; they have names beginning with
179c609719bSwdenk  "CFG_".
180c609719bSwdenk
181c609719bSwdenkLater we will add a configuration tool - probably similar to or even
182c609719bSwdenkidentical to what's used for the Linux kernel. Right now, we have to
183c609719bSwdenkdo the configuration by hand, which means creating some symbolic
184c609719bSwdenklinks and editing some configuration files. We use the TQM8xxL boards
185c609719bSwdenkas an example here.
186c609719bSwdenk
187c609719bSwdenk
188c609719bSwdenkSelection of Processor Architecture and Board Type:
189c609719bSwdenk---------------------------------------------------
190c609719bSwdenk
191c609719bSwdenkFor all supported boards there are ready-to-use default
192c609719bSwdenkconfigurations available; just type "make <board_name>_config".
193c609719bSwdenk
194c609719bSwdenkExample: For a TQM823L module type:
195c609719bSwdenk
196c609719bSwdenk	cd u-boot
197c609719bSwdenk	make TQM823L_config
198c609719bSwdenk
199c609719bSwdenkFor the Cogent platform, you need to specify the cpu type as well;
200c609719bSwdenke.g. "make cogent_mpc8xx_config". And also configure the cogent
201c609719bSwdenkdirectory according to the instructions in cogent/README.
202c609719bSwdenk
203c609719bSwdenk
204c609719bSwdenkConfiguration Options:
205c609719bSwdenk----------------------
206c609719bSwdenk
207c609719bSwdenkConfiguration depends on the combination of board and CPU type; all
208c609719bSwdenksuch information is kept in a configuration file
209c609719bSwdenk"include/configs/<board_name>.h".
210c609719bSwdenk
211c609719bSwdenkExample: For a TQM823L module, all configuration settings are in
212c609719bSwdenk"include/configs/TQM823L.h".
213c609719bSwdenk
214c609719bSwdenk
2157f6c2cbcSwdenkMany of the options are named exactly as the corresponding Linux
2167f6c2cbcSwdenkkernel configuration options. The intention is to make it easier to
2177f6c2cbcSwdenkbuild a config tool - later.
2187f6c2cbcSwdenk
2197f6c2cbcSwdenk
220c609719bSwdenkThe following options need to be configured:
221c609719bSwdenk
222c609719bSwdenk- CPU Type:	Define exactly one of
223c609719bSwdenk
224c609719bSwdenk		PowerPC based CPUs:
225c609719bSwdenk		-------------------
226c609719bSwdenk		CONFIG_MPC823,	CONFIG_MPC850,	CONFIG_MPC855,	CONFIG_MPC860
2270db5bca8Swdenk	or	CONFIG_MPC5xx
228c609719bSwdenk	or	CONFIG_MPC824X, CONFIG_MPC8260
22942d1f039Swdenk	or	CONFIG_MPC85xx
230c609719bSwdenk	or	CONFIG_IOP480
231c609719bSwdenk	or	CONFIG_405GP
23212f34241Swdenk	or	CONFIG_405EP
233c609719bSwdenk	or	CONFIG_440
234c609719bSwdenk	or	CONFIG_MPC74xx
23572755c71Swdenk	or	CONFIG_750FX
236c609719bSwdenk
237c609719bSwdenk		ARM based CPUs:
238c609719bSwdenk		---------------
239c609719bSwdenk		CONFIG_SA1110
240c609719bSwdenk		CONFIG_ARM7
241c609719bSwdenk		CONFIG_PXA250
242c609719bSwdenk
243c609719bSwdenk
244c609719bSwdenk- Board Type:	Define exactly one of
245c609719bSwdenk
246c609719bSwdenk		PowerPC based boards:
247c609719bSwdenk		---------------------
248c609719bSwdenk
249c609719bSwdenk		CONFIG_ADCIOP,	   CONFIG_ICU862      CONFIG_RPXsuper,
250c609719bSwdenk		CONFIG_ADS860,	   CONFIG_IP860,      CONFIG_SM850,
251c609719bSwdenk		CONFIG_AMX860,	   CONFIG_IPHASE4539, CONFIG_SPD823TS,
252c609719bSwdenk		CONFIG_AR405,	   CONFIG_IVML24,     CONFIG_SXNI855T,
253c609719bSwdenk		CONFIG_BAB7xx,	   CONFIG_IVML24_128, CONFIG_Sandpoint8240,
254c609719bSwdenk		CONFIG_CANBT,	   CONFIG_IVML24_256, CONFIG_Sandpoint8245,
255c609719bSwdenk		CONFIG_CCM,	   CONFIG_IVMS8,      CONFIG_TQM823L,
256c609719bSwdenk		CONFIG_CPCI405,	   CONFIG_IVMS8_128,  CONFIG_TQM850L,
257c609719bSwdenk		CONFIG_CPCI4052,   CONFIG_IVMS8_256,  CONFIG_TQM855L,
258c609719bSwdenk		CONFIG_CPCIISER4,  CONFIG_LANTEC,     CONFIG_TQM860L,
259c609719bSwdenk		CONFIG_CPU86,	   CONFIG_MBX,	      CONFIG_TQM8260,
260c609719bSwdenk		CONFIG_CRAYL1,	   CONFIG_MBX860T,    CONFIG_TTTech,
261c609719bSwdenk		CONFIG_CU824,	   CONFIG_MHPC,	      CONFIG_UTX8245,
262c609719bSwdenk		CONFIG_DASA_SIM,   CONFIG_MIP405,     CONFIG_W7OLMC,
263c609719bSwdenk		CONFIG_DU405,	   CONFIG_MOUSSE,     CONFIG_W7OLMG,
264c609719bSwdenk		CONFIG_ELPPC,	   CONFIG_MPC8260ADS, CONFIG_WALNUT405,
265c609719bSwdenk		CONFIG_ERIC,	   CONFIG_MUSENKI,    CONFIG_ZUMA,
266c609719bSwdenk		CONFIG_ESTEEM192E, CONFIG_MVS1,	      CONFIG_c2mon,
267c609719bSwdenk		CONFIG_ETX094,	   CONFIG_NX823,      CONFIG_cogent_mpc8260,
268c609719bSwdenk		CONFIG_EVB64260,   CONFIG_OCRTC,      CONFIG_cogent_mpc8xx,
269c609719bSwdenk		CONFIG_FADS823,	   CONFIG_ORSG,	      CONFIG_ep8260,
270c609719bSwdenk		CONFIG_FADS850SAR, CONFIG_OXC,	      CONFIG_gw8260,
271c609719bSwdenk		CONFIG_FADS860T,   CONFIG_PCI405,     CONFIG_hermes,
272c609719bSwdenk		CONFIG_FLAGADM,	   CONFIG_PCIPPC2,    CONFIG_hymod,
273c609719bSwdenk		CONFIG_FPS850L,	   CONFIG_PCIPPC6,    CONFIG_lwmon,
274c609719bSwdenk		CONFIG_GEN860T,	   CONFIG_PIP405,     CONFIG_pcu_e,
275c609719bSwdenk		CONFIG_GENIETV,	   CONFIG_PM826,      CONFIG_ppmc8260,
276c609719bSwdenk		CONFIG_GTH,	   CONFIG_RPXClassic, CONFIG_rsdproto,
277c609719bSwdenk		CONFIG_IAD210,	   CONFIG_RPXlite,    CONFIG_sbc8260,
278608c9146Swdenk		CONFIG_EBONY,	   CONFIG_sacsng,     CONFIG_FPS860L,
2797f70e853Swdenk		CONFIG_V37,	   CONFIG_ELPT860,    CONFIG_CMI,
28042d1f039Swdenk		CONFIG_NETVIA,	   CONFIG_RBC823,     CONFIG_ZPC1900,
2813a473b2aSwdenk		CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850,
2823a473b2aSwdenk		CONFIG_QS823,	   CONFIG_QS860T,     CONFIG_DB64360,
283180d3f74Swdenk		CONFIG_DB64460,	   CONFIG_DUET_ADS
284c609719bSwdenk
285c609719bSwdenk		ARM based boards:
286c609719bSwdenk		-----------------
287c609719bSwdenk
288c609719bSwdenk		CONFIG_HHP_CRADLE,  CONFIG_DNP1110,	CONFIG_EP7312,
289c609719bSwdenk		CONFIG_IMPA7,	    CONFIG_LART,	CONFIG_LUBBOCK,
29063e73c9aSwdenk		CONFIG_INNOVATOROMAP1510,      CONFIG_INNOVATOROMAP1610,
29163e73c9aSwdenk		CONFIG_H2_OMAP1610, CONFIG_SHANNON,	CONFIG_SMDK2400,
29263e73c9aSwdenk		CONFIG_SMDK2410,    CONFIG_TRAB,	CONFIG_VCMA9,
29363e73c9aSwdenk		CONFIG_AT91RM9200DK
294c609719bSwdenk
295c609719bSwdenk
296c609719bSwdenk- CPU Module Type: (if CONFIG_COGENT is defined)
297c609719bSwdenk		Define exactly one of
298c609719bSwdenk		CONFIG_CMA286_60_OLD
299c609719bSwdenk--- FIXME --- not tested yet:
300c609719bSwdenk		CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
301c609719bSwdenk		CONFIG_CMA287_23, CONFIG_CMA287_50
302c609719bSwdenk
303c609719bSwdenk- Motherboard Type: (if CONFIG_COGENT is defined)
304c609719bSwdenk		Define exactly one of
305c609719bSwdenk		CONFIG_CMA101, CONFIG_CMA102
306c609719bSwdenk
307c609719bSwdenk- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
308c609719bSwdenk		Define one or more of
309c609719bSwdenk		CONFIG_CMA302
310c609719bSwdenk
311c609719bSwdenk- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
312c609719bSwdenk		Define one or more of
313c609719bSwdenk		CONFIG_LCD_HEARTBEAT	- update a character position on
314c609719bSwdenk					  the lcd display every second with
315c609719bSwdenk					  a "rotator" |\-/|\-/
316c609719bSwdenk
3172535d602Swdenk- Board flavour: (if CONFIG_MPC8260ADS is defined)
3182535d602Swdenk		CONFIG_ADSTYPE
3192535d602Swdenk		Possible values are:
3202535d602Swdenk			CFG_8260ADS	- original MPC8260ADS
321180d3f74Swdenk			CFG_8266ADS	- MPC8266ADS
32254387ac9Swdenk			CFG_PQ2FADS	- PQ2FADS-ZU or PQ2FADS-VR
3232535d602Swdenk
3242535d602Swdenk
325c609719bSwdenk- MPC824X Family Member (if CONFIG_MPC824X is defined)
326c609719bSwdenk		Define exactly one of
327c609719bSwdenk		CONFIG_MPC8240, CONFIG_MPC8245
328c609719bSwdenk
32975d1ea7fSwdenk- 8xx CPU Options: (if using an MPC8xx cpu)
330c609719bSwdenk		Define one or more of
3315da627a4Swdenk		CONFIG_8xx_GCLK_FREQ	- if get_gclk_freq() cannot work
3325da627a4Swdenk					  e.g. if there is no 32KHz
3335da627a4Swdenk					  reference PIT/RTC clock
334c609719bSwdenk
33575d1ea7fSwdenk- 859/866 CPU options: (if using a MPC859 or MPC866 CPU):
33675d1ea7fSwdenk		CFG_866_OSCCLK
33775d1ea7fSwdenk		CFG_866_CPUCLK_MIN
33875d1ea7fSwdenk		CFG_866_CPUCLK_MAX
33975d1ea7fSwdenk		CFG_866_CPUCLK_DEFAULT
34075d1ea7fSwdenk			See doc/README.MPC866
34175d1ea7fSwdenk
34275d1ea7fSwdenk		CFG_MEASURE_CPUCLK
34375d1ea7fSwdenk
34475d1ea7fSwdenk		Define this to measure the actual CPU clock instead
34575d1ea7fSwdenk		of relying on the correctness of the configured
34675d1ea7fSwdenk		values. Mostly useful for board bringup to make sure
34775d1ea7fSwdenk		the PLL is locked at the intended frequency. Note
34875d1ea7fSwdenk		that this requires a (stable) reference clock (32 kHz
34975d1ea7fSwdenk		RTC clock),
35075d1ea7fSwdenk
3515da627a4Swdenk- Linux Kernel Interface:
352c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
353c609719bSwdenk
354c609719bSwdenk		U-Boot stores all clock information in Hz
355c609719bSwdenk		internally. For binary compatibility with older Linux
356c609719bSwdenk		kernels (which expect the clocks passed in the
357c609719bSwdenk		bd_info data to be in MHz) the environment variable
358c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
359c609719bSwdenk		converts clock data to MHZ before passing it to the
360c609719bSwdenk		Linux kernel.
361c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
362c609719bSwdenk		"clocks_in_mhz=1" is  automatically  included  in  the
363c609719bSwdenk		default environment.
364c609719bSwdenk
3655da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
3665da627a4Swdenk
3675da627a4Swdenk		When transfering memsize parameter to linux, some versions
3685da627a4Swdenk		expect it to be in bytes, others in MB.
3695da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
3705da627a4Swdenk
371c609719bSwdenk- Console Interface:
372c609719bSwdenk		Depending on board, define exactly one serial port
373c609719bSwdenk		(like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
374c609719bSwdenk		CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
375c609719bSwdenk		console by defining CONFIG_8xx_CONS_NONE
376c609719bSwdenk
377c609719bSwdenk		Note: if CONFIG_8xx_CONS_NONE is defined, the serial
378c609719bSwdenk		port routines must be defined elsewhere
379c609719bSwdenk		(i.e. serial_init(), serial_getc(), ...)
380c609719bSwdenk
381c609719bSwdenk		CONFIG_CFB_CONSOLE
382c609719bSwdenk		Enables console device for a color framebuffer. Needs following
383c609719bSwdenk		defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
384c609719bSwdenk			VIDEO_FB_LITTLE_ENDIAN	graphic memory organisation
385c609719bSwdenk						(default big endian)
386c609719bSwdenk			VIDEO_HW_RECTFILL	graphic chip supports
387c609719bSwdenk						rectangle fill
388c609719bSwdenk						(cf. smiLynxEM)
389c609719bSwdenk			VIDEO_HW_BITBLT		graphic chip supports
390c609719bSwdenk						bit-blit (cf. smiLynxEM)
391c609719bSwdenk			VIDEO_VISIBLE_COLS	visible pixel columns
392c609719bSwdenk						(cols=pitch)
393c609719bSwdenk			VIDEO_VISIBLE_ROWS	visible pixel rows
394c609719bSwdenk			VIDEO_PIXEL_SIZE	bytes per pixel
395c609719bSwdenk			VIDEO_DATA_FORMAT	graphic data format
396c609719bSwdenk						(0-5, cf. cfb_console.c)
397c609719bSwdenk			VIDEO_FB_ADRS		framebuffer address
398c609719bSwdenk			VIDEO_KBD_INIT_FCT	keyboard int fct
399c609719bSwdenk						(i.e. i8042_kbd_init())
400c609719bSwdenk			VIDEO_TSTC_FCT		test char fct
401c609719bSwdenk						(i.e. i8042_tstc)
402c609719bSwdenk			VIDEO_GETC_FCT		get char fct
403c609719bSwdenk						(i.e. i8042_getc)
404c609719bSwdenk			CONFIG_CONSOLE_CURSOR	cursor drawing on/off
405c609719bSwdenk						(requires blink timer
406c609719bSwdenk						cf. i8042.c)
407c609719bSwdenk			CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
408c609719bSwdenk			CONFIG_CONSOLE_TIME	display time/date info in
409c609719bSwdenk						upper right corner
410c609719bSwdenk						(requires CFG_CMD_DATE)
411c609719bSwdenk			CONFIG_VIDEO_LOGO	display Linux logo in
412c609719bSwdenk						upper left corner
413a6c7ad2fSwdenk			CONFIG_VIDEO_BMP_LOGO	use bmp_logo.h instead of
414a6c7ad2fSwdenk						linux_logo.h for logo.
415a6c7ad2fSwdenk						Requires CONFIG_VIDEO_LOGO
416c609719bSwdenk			CONFIG_CONSOLE_EXTRA_INFO
417c609719bSwdenk						addional board info beside
418c609719bSwdenk						the logo
419c609719bSwdenk
420c609719bSwdenk		When CONFIG_CFB_CONSOLE is defined, video console is
421c609719bSwdenk		default i/o. Serial console can be forced with
422c609719bSwdenk		environment 'console=serial'.
423c609719bSwdenk
424a3ad8e26Swdenk		When CONFIG_SILENT_CONSOLE is defined, all console
425a3ad8e26Swdenk		messages (by U-Boot and Linux!) can be silenced with
426a3ad8e26Swdenk		the "silent" environment variable. See
427a3ad8e26Swdenk		doc/README.silent for more information.
428a3ad8e26Swdenk
429c609719bSwdenk- Console Baudrate:
430c609719bSwdenk		CONFIG_BAUDRATE - in bps
431c609719bSwdenk		Select one of the baudrates listed in
432c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
4333bbc899fSwdenk		CFG_BRGCLK_PRESCALE, baudrate prescale
434c609719bSwdenk
435c609719bSwdenk- Interrupt driven serial port input:
436c609719bSwdenk		CONFIG_SERIAL_SOFTWARE_FIFO
437c609719bSwdenk
438c609719bSwdenk		PPC405GP only.
439c609719bSwdenk		Use an interrupt handler for receiving data on the
440c609719bSwdenk		serial port. It also enables using hardware handshake
441c609719bSwdenk		(RTS/CTS) and UART's built-in FIFO. Set the number of
442c609719bSwdenk		bytes the interrupt driven input buffer should have.
443c609719bSwdenk
444c609719bSwdenk		Set to 0 to disable this feature (this is the default).
445c609719bSwdenk		This will also disable hardware handshake.
446c609719bSwdenk
4471d49b1f3Sstroese- Console UART Number:
4481d49b1f3Sstroese		CONFIG_UART1_CONSOLE
4491d49b1f3Sstroese
4501d49b1f3Sstroese		IBM PPC4xx only.
4511d49b1f3Sstroese		If defined internal UART1 (and not UART0) is used
4521d49b1f3Sstroese		as default U-Boot console.
4531d49b1f3Sstroese
454c609719bSwdenk- Boot Delay:	CONFIG_BOOTDELAY - in seconds
455c609719bSwdenk		Delay before automatically booting the default image;
456c609719bSwdenk		set to -1 to disable autoboot.
457c609719bSwdenk
458c609719bSwdenk		See doc/README.autoboot for these options that
459c609719bSwdenk		work with CONFIG_BOOTDELAY. None are required.
460c609719bSwdenk		CONFIG_BOOT_RETRY_TIME
461c609719bSwdenk		CONFIG_BOOT_RETRY_MIN
462c609719bSwdenk		CONFIG_AUTOBOOT_KEYED
463c609719bSwdenk		CONFIG_AUTOBOOT_PROMPT
464c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR
465c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR
466c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR2
467c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR2
468c609719bSwdenk		CONFIG_ZERO_BOOTDELAY_CHECK
469c609719bSwdenk		CONFIG_RESET_TO_RETRY
470c609719bSwdenk
471c609719bSwdenk- Autoboot Command:
472c609719bSwdenk		CONFIG_BOOTCOMMAND
473c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
474c609719bSwdenk		define a command string that is automatically executed
475c609719bSwdenk		when no character is read on the console interface
476c609719bSwdenk		within "Boot Delay" after reset.
477c609719bSwdenk
478c609719bSwdenk		CONFIG_BOOTARGS
479c609719bSwdenk		This can be used to pass arguments to the bootm
480c609719bSwdenk		command. The value of CONFIG_BOOTARGS goes into the
481c609719bSwdenk		environment value "bootargs".
482c609719bSwdenk
483c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
484c609719bSwdenk		The value of these goes into the environment as
485c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
486c609719bSwdenk		as a convenience, when switching between booting from
487c609719bSwdenk		ram and nfs.
488c609719bSwdenk
489c609719bSwdenk- Pre-Boot Commands:
490c609719bSwdenk		CONFIG_PREBOOT
491c609719bSwdenk
492c609719bSwdenk		When this option is #defined, the existence of the
493c609719bSwdenk		environment variable "preboot" will be checked
494c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
495c609719bSwdenk		countdown and/or running the auto-boot command resp.
496c609719bSwdenk		entering interactive mode.
497c609719bSwdenk
498c609719bSwdenk		This feature is especially useful when "preboot" is
499c609719bSwdenk		automatically generated or modified. For an example
500c609719bSwdenk		see the LWMON board specific code: here "preboot" is
501c609719bSwdenk		modified when the user holds down a certain
502c609719bSwdenk		combination of keys on the (special) keyboard when
503c609719bSwdenk		booting the systems
504c609719bSwdenk
505c609719bSwdenk- Serial Download Echo Mode:
506c609719bSwdenk		CONFIG_LOADS_ECHO
507c609719bSwdenk		If defined to 1, all characters received during a
508c609719bSwdenk		serial download (using the "loads" command) are
509c609719bSwdenk		echoed back. This might be needed by some terminal
510c609719bSwdenk		emulations (like "cu"), but may as well just take
511c609719bSwdenk		time on others. This setting #define's the initial
512c609719bSwdenk		value of the "loads_echo" environment variable.
513c609719bSwdenk
514c609719bSwdenk- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
515c609719bSwdenk		CONFIG_KGDB_BAUDRATE
516c609719bSwdenk		Select one of the baudrates listed in
517c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
518c609719bSwdenk
519c609719bSwdenk- Monitor Functions:
520c609719bSwdenk		CONFIG_COMMANDS
521c609719bSwdenk		Most monitor functions can be selected (or
522c609719bSwdenk		de-selected) by adjusting the definition of
523c609719bSwdenk		CONFIG_COMMANDS; to select individual functions,
524c609719bSwdenk		#define CONFIG_COMMANDS by "OR"ing any of the
525c609719bSwdenk		following values:
526c609719bSwdenk
527c609719bSwdenk		#define enables commands:
528c609719bSwdenk		-------------------------
529c609719bSwdenk		CFG_CMD_ASKENV	* ask for env variable
53078137c3cSwdenk		CFG_CMD_AUTOSCRIPT Autoscript Support
531c609719bSwdenk		CFG_CMD_BDI	  bdinfo
532c609719bSwdenk		CFG_CMD_BEDBUG	  Include BedBug Debugger
53378137c3cSwdenk		CFG_CMD_BMP	* BMP support
534c609719bSwdenk		CFG_CMD_BOOTD	  bootd
535c609719bSwdenk		CFG_CMD_CACHE	  icache, dcache
536c609719bSwdenk		CFG_CMD_CONSOLE	  coninfo
537c609719bSwdenk		CFG_CMD_DATE	* support for RTC, date/time...
538c609719bSwdenk		CFG_CMD_DHCP	  DHCP support
53978137c3cSwdenk		CFG_CMD_DIAG	* Diagnostics
54078137c3cSwdenk		CFG_CMD_DOC	* Disk-On-Chip Support
54178137c3cSwdenk		CFG_CMD_DTT	  Digital Therm and Thermostat
542c609719bSwdenk		CFG_CMD_ECHO	* echo arguments
543c609719bSwdenk		CFG_CMD_EEPROM	* EEPROM read/write support
544c609719bSwdenk		CFG_CMD_ELF	  bootelf, bootvx
545c609719bSwdenk		CFG_CMD_ENV	  saveenv
546c609719bSwdenk		CFG_CMD_FDC	* Floppy Disk Support
54771f95118Swdenk		CFG_CMD_FAT	  FAT partition support
5482262cfeeSwdenk		CFG_CMD_FDOS	* Dos diskette Support
549c609719bSwdenk		CFG_CMD_FLASH	  flinfo, erase, protect
550c609719bSwdenk		CFG_CMD_FPGA	  FPGA device initialization support
55178137c3cSwdenk		CFG_CMD_HWFLOW	* RTS/CTS hw flow control
552c609719bSwdenk		CFG_CMD_I2C	* I2C serial bus support
553c609719bSwdenk		CFG_CMD_IDE	* IDE harddisk support
554c609719bSwdenk		CFG_CMD_IMI	  iminfo
55578137c3cSwdenk		CFG_CMD_IMLS	  List all found images
556c609719bSwdenk		CFG_CMD_IMMAP	* IMMR dump support
557c609719bSwdenk		CFG_CMD_IRQ	* irqinfo
5582d1a537dSwdenk		CFG_CMD_ITEST	* Integer/string test of 2 values
55978137c3cSwdenk		CFG_CMD_JFFS2	* JFFS2 Support
560c609719bSwdenk		CFG_CMD_KGDB	* kgdb
561c609719bSwdenk		CFG_CMD_LOADB	  loadb
562c609719bSwdenk		CFG_CMD_LOADS	  loads
563c609719bSwdenk		CFG_CMD_MEMORY	  md, mm, nm, mw, cp, cmp, crc, base,
564c609719bSwdenk				  loop, mtest
56578137c3cSwdenk		CFG_CMD_MISC	  Misc functions like sleep etc
56671f95118Swdenk		CFG_CMD_MMC	  MMC memory mapped support
567c609719bSwdenk		CFG_CMD_MII	  MII utility commands
56878137c3cSwdenk		CFG_CMD_NAND	* NAND support
569c609719bSwdenk		CFG_CMD_NET	  bootp, tftpboot, rarpboot
570c609719bSwdenk		CFG_CMD_PCI	* pciinfo
571c609719bSwdenk		CFG_CMD_PCMCIA	* PCMCIA support
57278137c3cSwdenk		CFG_CMD_PING	* send ICMP ECHO_REQUEST to network host
573ef5a9672Swdenk		CFG_CMD_PORTIO	* Port I/O
574c609719bSwdenk		CFG_CMD_REGINFO * Register dump
575c609719bSwdenk		CFG_CMD_RUN	  run command in env variable
57678137c3cSwdenk		CFG_CMD_SAVES	  save S record dump
577c609719bSwdenk		CFG_CMD_SCSI	* SCSI Support
57878137c3cSwdenk		CFG_CMD_SDRAM	* print SDRAM configuration information
579c609719bSwdenk		CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
580c609719bSwdenk		CFG_CMD_SPI	* SPI serial bus support
581c609719bSwdenk		CFG_CMD_USB	* USB support
58278137c3cSwdenk		CFG_CMD_VFD	* VFD support (TRAB)
583c609719bSwdenk		CFG_CMD_BSP	* Board SPecific functions
584c609719bSwdenk		-----------------------------------------------
585c609719bSwdenk		CFG_CMD_ALL	all
586c609719bSwdenk
587c609719bSwdenk		CFG_CMD_DFL	Default configuration; at the moment
588c609719bSwdenk				this is includes all commands, except
589c609719bSwdenk				the ones marked with "*" in the list
590c609719bSwdenk				above.
591c609719bSwdenk
592c609719bSwdenk		If you don't define CONFIG_COMMANDS it defaults to
593c609719bSwdenk		CFG_CMD_DFL in include/cmd_confdefs.h. A board can
594c609719bSwdenk		override the default settings in the respective
595c609719bSwdenk		include file.
596c609719bSwdenk
597c609719bSwdenk		EXAMPLE: If you want all functions except of network
598c609719bSwdenk		support you can write:
599c609719bSwdenk
600c609719bSwdenk		#define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
601c609719bSwdenk
602c609719bSwdenk
603c609719bSwdenk	Note:	Don't enable the "icache" and "dcache" commands
604c609719bSwdenk		(configuration option CFG_CMD_CACHE) unless you know
605c609719bSwdenk		what you (and your U-Boot users) are doing. Data
606c609719bSwdenk		cache cannot be enabled on systems like the 8xx or
607c609719bSwdenk		8260 (where accesses to the IMMR region must be
608c609719bSwdenk		uncached), and it cannot be disabled on all other
609c609719bSwdenk		systems where we (mis-) use the data cache to hold an
610c609719bSwdenk		initial stack and some data.
611c609719bSwdenk
612c609719bSwdenk
613c609719bSwdenk		XXX - this list needs to get updated!
614c609719bSwdenk
615c609719bSwdenk- Watchdog:
616c609719bSwdenk		CONFIG_WATCHDOG
617c609719bSwdenk		If this variable is defined, it enables watchdog
6187152b1d0Swdenk		support. There must be support in the platform specific
619c609719bSwdenk		code for a watchdog. For the 8xx and 8260 CPUs, the
620c609719bSwdenk		SIU Watchdog feature is enabled in the SYPCR
621c609719bSwdenk		register.
622c609719bSwdenk
623c1551ea8Sstroese- U-Boot Version:
624c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
625c1551ea8Sstroese		If this variable is defined, an environment variable
626c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
627c1551ea8Sstroese		version as printed by the "version" command.
628c1551ea8Sstroese		This variable is readonly.
629c1551ea8Sstroese
630c609719bSwdenk- Real-Time Clock:
631c609719bSwdenk
632c609719bSwdenk		When CFG_CMD_DATE is selected, the type of the RTC
633c609719bSwdenk		has to be selected, too. Define exactly one of the
634c609719bSwdenk		following options:
635c609719bSwdenk
636c609719bSwdenk		CONFIG_RTC_MPC8xx	- use internal RTC of MPC8xx
637c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
638c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
6391cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
640c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
6417f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
6423bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
643c609719bSwdenk
644b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
645b37c7e5eSwdenk		must also be configured. See I2C Support, below.
646b37c7e5eSwdenk
647c609719bSwdenk- Timestamp Support:
648c609719bSwdenk
649c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
650c609719bSwdenk		(date and time) of an image is printed by image
651c609719bSwdenk		commands like bootm or iminfo. This option is
652c609719bSwdenk		automatically enabled when you select CFG_CMD_DATE .
653c609719bSwdenk
654c609719bSwdenk- Partition Support:
655c609719bSwdenk		CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
656c609719bSwdenk		and/or CONFIG_ISO_PARTITION
657c609719bSwdenk
658c609719bSwdenk		If IDE or SCSI support	is  enabled  (CFG_CMD_IDE  or
659c609719bSwdenk		CFG_CMD_SCSI) you must configure support for at least
660c609719bSwdenk		one partition type as well.
661c609719bSwdenk
662c609719bSwdenk- IDE Reset method:
663c609719bSwdenk		CONFIG_IDE_RESET_ROUTINE
664c609719bSwdenk
665c609719bSwdenk		Set this to define that instead of a reset Pin, the
666c609719bSwdenk		routine ide_set_reset(int idereset) will be used.
667c609719bSwdenk
668c609719bSwdenk- ATAPI Support:
669c609719bSwdenk		CONFIG_ATAPI
670c609719bSwdenk
671c609719bSwdenk		Set this to enable ATAPI support.
672c609719bSwdenk
673*c40b2956Swdenk- LBA48 Support
674*c40b2956Swdenk		CONFIG_LBA48
675*c40b2956Swdenk
676*c40b2956Swdenk		Set this to enable support for disks larger than 137GB
677*c40b2956Swdenk		Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
678*c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
679*c40b2956Swdenk		support disks up to 2.1TB.
680*c40b2956Swdenk
681*c40b2956Swdenk		CFG_64BIT_LBA:
682*c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
683*c40b2956Swdenk			Default is 32bit.
684*c40b2956Swdenk
685c609719bSwdenk- SCSI Support:
686c609719bSwdenk		At the moment only there is only support for the
687c609719bSwdenk		SYM53C8XX SCSI controller; define
688c609719bSwdenk		CONFIG_SCSI_SYM53C8XX to enable it.
689c609719bSwdenk
690c609719bSwdenk		CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
691c609719bSwdenk		CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
692c609719bSwdenk		CFG_SCSI_MAX_LUN] can be adjusted to define the
693c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
694c609719bSwdenk		devices.
695c609719bSwdenk		CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
696c609719bSwdenk
697c609719bSwdenk- NETWORK Support (PCI):
698682011ffSwdenk		CONFIG_E1000
699682011ffSwdenk		Support for Intel 8254x gigabit chips.
700682011ffSwdenk
701c609719bSwdenk		CONFIG_EEPRO100
702c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
703c609719bSwdenk		Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
704c609719bSwdenk		write routine for first time initialisation.
705c609719bSwdenk
706c609719bSwdenk		CONFIG_TULIP
707c609719bSwdenk		Support for Digital 2114x chips.
708c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
709c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
710c609719bSwdenk
711c609719bSwdenk		CONFIG_NATSEMI
712c609719bSwdenk		Support for National dp83815 chips.
713c609719bSwdenk
714c609719bSwdenk		CONFIG_NS8382X
715c609719bSwdenk		Support for National dp8382[01] gigabit chips.
716c609719bSwdenk
71745219c46Swdenk- NETWORK Support (other):
71845219c46Swdenk
71945219c46Swdenk		CONFIG_DRIVER_LAN91C96
72045219c46Swdenk		Support for SMSC's LAN91C96 chips.
72145219c46Swdenk
72245219c46Swdenk			CONFIG_LAN91C96_BASE
72345219c46Swdenk			Define this to hold the physical address
72445219c46Swdenk			of the LAN91C96's I/O space
72545219c46Swdenk
72645219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
72745219c46Swdenk			Define this to enable 32 bit addressing
72845219c46Swdenk
729c609719bSwdenk- USB Support:
730c609719bSwdenk		At the moment only the UHCI host controller is
731c609719bSwdenk		supported (PIP405, MIP405); define
732c609719bSwdenk		CONFIG_USB_UHCI to enable it.
733c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
734c609719bSwdenk		end define CONFIG_USB_STORAGE to enable the USB
735c609719bSwdenk		storage devices.
736c609719bSwdenk		Note:
737c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
738c609719bSwdenk		(TEAC FD-05PUB).
739c609719bSwdenk
74071f95118Swdenk- MMC Support:
74171f95118Swdenk		The MMC controller on the Intel PXA is supported. To
74271f95118Swdenk		enable this define CONFIG_MMC. The MMC can be
74371f95118Swdenk		accessed from the boot prompt by mapping the device
74471f95118Swdenk		to physical memory similar to flash. Command line is
74571f95118Swdenk		enabled with CFG_CMD_MMC. The MMC driver also works with
74671f95118Swdenk		the FAT fs. This is enabled with CFG_CMD_FAT.
74771f95118Swdenk
748c609719bSwdenk- Keyboard Support:
749c609719bSwdenk		CONFIG_ISA_KEYBOARD
750c609719bSwdenk
751c609719bSwdenk		Define this to enable standard (PC-Style) keyboard
752c609719bSwdenk		support
753c609719bSwdenk
754c609719bSwdenk		CONFIG_I8042_KBD
755c609719bSwdenk		Standard PC keyboard driver with US (is default) and
756c609719bSwdenk		GERMAN key layout (switch via environment 'keymap=de') support.
757c609719bSwdenk		Export function i8042_kbd_init, i8042_tstc and i8042_getc
758c609719bSwdenk		for cfb_console. Supports cursor blinking.
759c609719bSwdenk
760c609719bSwdenk- Video support:
761c609719bSwdenk		CONFIG_VIDEO
762c609719bSwdenk
763c609719bSwdenk		Define this to enable video support (for output to
764c609719bSwdenk		video).
765c609719bSwdenk
766c609719bSwdenk		CONFIG_VIDEO_CT69000
767c609719bSwdenk
768c609719bSwdenk		Enable Chips & Technologies 69000 Video chip
769c609719bSwdenk
770c609719bSwdenk		CONFIG_VIDEO_SMI_LYNXEM
771c609719bSwdenk		Enable Silicon Motion SMI 712/710/810 Video chip
772c609719bSwdenk		Videomode are selected via environment 'videomode' with
773c609719bSwdenk		standard LiLo mode numbers.
774c609719bSwdenk		Following modes are supported  (* is default):
775c609719bSwdenk
776c609719bSwdenk			    800x600  1024x768  1280x1024
777c609719bSwdenk	      256  (8bit)     303*	305	  307
778c609719bSwdenk	    65536 (16bit)     314	317	  31a
779c609719bSwdenk	16,7 Mill (24bit)     315	318	  31b
780c609719bSwdenk		(i.e. setenv videomode 317; saveenv; reset;)
781c609719bSwdenk
782a6c7ad2fSwdenk		CONFIG_VIDEO_SED13806
783a6c7ad2fSwdenk		Enable Epson SED13806 driver. This driver supports 8bpp
784a6c7ad2fSwdenk		and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
785a6c7ad2fSwdenk		or CONFIG_VIDEO_SED13806_16BPP
786a6c7ad2fSwdenk
787682011ffSwdenk- Keyboard Support:
788682011ffSwdenk		CONFIG_KEYBOARD
789682011ffSwdenk
790682011ffSwdenk		Define this to enable a custom keyboard support.
791682011ffSwdenk		This simply calls drv_keyboard_init() which must be
792682011ffSwdenk		defined in your board-specific files.
793682011ffSwdenk		The only board using this so far is RBC823.
794a6c7ad2fSwdenk
795c609719bSwdenk- LCD Support:	CONFIG_LCD
796c609719bSwdenk
797c609719bSwdenk		Define this to enable LCD support (for output to LCD
798c609719bSwdenk		display); also select one of the supported displays
799c609719bSwdenk		by defining one of these:
800c609719bSwdenk
801fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
802c609719bSwdenk
803fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
804c609719bSwdenk
805fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
806c609719bSwdenk
807fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
808fd3103bbSwdenk			Active, color, single scan.
809fd3103bbSwdenk
810fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
811fd3103bbSwdenk
812fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
813c609719bSwdenk			Active, color, single scan.
814c609719bSwdenk
815c609719bSwdenk		CONFIG_SHARP_16x9
816c609719bSwdenk
817c609719bSwdenk			Sharp 320x240. Active, color, single scan.
818c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
819c609719bSwdenk
820c609719bSwdenk		CONFIG_SHARP_LQ64D341
821c609719bSwdenk
822c609719bSwdenk			Sharp LQ64D341 display, 640x480.
823c609719bSwdenk			Active, color, single scan.
824c609719bSwdenk
825c609719bSwdenk		CONFIG_HLD1045
826c609719bSwdenk
827c609719bSwdenk			HLD1045 display, 640x480.
828c609719bSwdenk			Active, color, single scan.
829c609719bSwdenk
830c609719bSwdenk		CONFIG_OPTREX_BW
831c609719bSwdenk
832c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
833c609719bSwdenk			or
834c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
835c609719bSwdenk			or
836c609719bSwdenk			Hitachi	 SP14Q002
837c609719bSwdenk
838c609719bSwdenk			320x240. Black & white.
839c609719bSwdenk
840c609719bSwdenk		Normally display is black on white background; define
841c609719bSwdenk		CFG_WHITE_ON_BLACK to get it inverted.
842c609719bSwdenk
8437152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
844d791b1dcSwdenk
845d791b1dcSwdenk		If this option is set, the environment is checked for
846d791b1dcSwdenk		a variable "splashimage". If found, the usual display
847d791b1dcSwdenk		of logo, copyright and system information on the LCD
848d791b1dcSwdenk		is supressed and the BMP image at the address
849d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
850d791b1dcSwdenk		console is redirected to the "nulldev", too. This
851d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
852d791b1dcSwdenk		loaded very quickly after power-on.
853d791b1dcSwdenk
854c29fdfc1Swdenk- Compression support:
855c29fdfc1Swdenk		CONFIG_BZIP2
856c29fdfc1Swdenk
857c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
858c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
859c29fdfc1Swdenk		compressed images are supported.
860c29fdfc1Swdenk
861c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
862c29fdfc1Swdenk		the malloc area (as defined by CFG_MALLOC_LEN) should
863c29fdfc1Swdenk		be at least 4MB.
864d791b1dcSwdenk
865c609719bSwdenk- Ethernet address:
866c609719bSwdenk		CONFIG_ETHADDR
867c609719bSwdenk		CONFIG_ETH2ADDR
868c609719bSwdenk		CONFIG_ETH3ADDR
869c609719bSwdenk
870c609719bSwdenk		Define a default value for ethernet address to use
871c609719bSwdenk		for the respective ethernet interface, in case this
872c609719bSwdenk		is not determined automatically.
873c609719bSwdenk
874c609719bSwdenk- IP address:
875c609719bSwdenk		CONFIG_IPADDR
876c609719bSwdenk
877c609719bSwdenk		Define a default value for the IP address to use for
878c609719bSwdenk		the default ethernet interface, in case this is not
879c609719bSwdenk		determined through e.g. bootp.
880c609719bSwdenk
881c609719bSwdenk- Server IP address:
882c609719bSwdenk		CONFIG_SERVERIP
883c609719bSwdenk
884c609719bSwdenk		Defines a default value for theIP address of a TFTP
885c609719bSwdenk		server to contact when using the "tftboot" command.
886c609719bSwdenk
887c609719bSwdenk- BOOTP Recovery Mode:
888c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
889c609719bSwdenk
890c609719bSwdenk		If you have many targets in a network that try to
891c609719bSwdenk		boot using BOOTP, you may want to avoid that all
892c609719bSwdenk		systems send out BOOTP requests at precisely the same
893c609719bSwdenk		moment (which would happen for instance at recovery
894c609719bSwdenk		from a power failure, when all systems will try to
895c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
896c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
897c609719bSwdenk		inserted before sending out BOOTP requests. The
898c609719bSwdenk		following delays are insterted then:
899c609719bSwdenk
900c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
901c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
902c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
903c609719bSwdenk		4th and following
904c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
905c609719bSwdenk
906fe389a82Sstroese- DHCP Advanced Options:
907fe389a82Sstroese		CONFIG_BOOTP_MASK
908fe389a82Sstroese
909fe389a82Sstroese		You can fine tune the DHCP functionality by adding
910fe389a82Sstroese		these flags to the CONFIG_BOOTP_MASK define:
911fe389a82Sstroese
912fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
913fe389a82Sstroese		serverip from a DHCP server, it is possible that more
914fe389a82Sstroese		than one DNS serverip is offered to the client.
915fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
916fe389a82Sstroese		serverip will be stored in the additional environment
917fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
918fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
919fe389a82Sstroese		is added to the CONFIG_BOOTP_MASK.
920fe389a82Sstroese
921fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
922fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
923fe389a82Sstroese		need the hostname of the DHCP requester.
924fe389a82Sstroese		If CONFIG_BOOP_SEND_HOSTNAME is added to the
925fe389a82Sstroese		CONFIG_BOOTP_MASK, the content of the "hostname"
926fe389a82Sstroese		environment variable is passed as option 12 to
927fe389a82Sstroese		the DHCP server.
928fe389a82Sstroese
929c609719bSwdenk- Status LED:	CONFIG_STATUS_LED
930c609719bSwdenk
931c609719bSwdenk		Several configurations allow to display the current
932c609719bSwdenk		status using a LED. For instance, the LED will blink
933c609719bSwdenk		fast while running U-Boot code, stop blinking as
934c609719bSwdenk		soon as a reply to a BOOTP request was received, and
935c609719bSwdenk		start blinking slow once the Linux kernel is running
936c609719bSwdenk		(supported by a status LED driver in the Linux
937c609719bSwdenk		kernel). Defining CONFIG_STATUS_LED enables this
938c609719bSwdenk		feature in U-Boot.
939c609719bSwdenk
940c609719bSwdenk- CAN Support:	CONFIG_CAN_DRIVER
941c609719bSwdenk
942c609719bSwdenk		Defining CONFIG_CAN_DRIVER enables CAN driver support
943c609719bSwdenk		on those systems that support this (optional)
944c609719bSwdenk		feature, like the TQM8xxL modules.
945c609719bSwdenk
946c609719bSwdenk- I2C Support:	CONFIG_HARD_I2C | CONFIG_SOFT_I2C
947c609719bSwdenk
948b37c7e5eSwdenk		These enable I2C serial bus commands. Defining either of
949b37c7e5eSwdenk		(but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
950b37c7e5eSwdenk		include the appropriate I2C driver for the selected cpu.
951c609719bSwdenk
952b37c7e5eSwdenk		This will allow you to use i2c commands at the u-boot
953b37c7e5eSwdenk		command line (as long as you set CFG_CMD_I2C in
954b37c7e5eSwdenk		CONFIG_COMMANDS) and communicate with i2c based realtime
955b37c7e5eSwdenk		clock chips. See common/cmd_i2c.c for a description of the
956c609719bSwdenk		command line interface.
957c609719bSwdenk
958b37c7e5eSwdenk		CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
959c609719bSwdenk
960b37c7e5eSwdenk		CONFIG_SOFT_I2C configures u-boot to use a software (aka
961b37c7e5eSwdenk		bit-banging) driver instead of CPM or similar hardware
962b37c7e5eSwdenk		support for I2C.
963c609719bSwdenk
964b37c7e5eSwdenk		There are several other quantities that must also be
965b37c7e5eSwdenk		defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
966c609719bSwdenk
967b37c7e5eSwdenk		In both cases you will need to define CFG_I2C_SPEED
968b37c7e5eSwdenk		to be the frequency (in Hz) at which you wish your i2c bus
969b37c7e5eSwdenk		to run and CFG_I2C_SLAVE to be the address of this node (ie
970b37c7e5eSwdenk		the cpu's i2c node address).
971c609719bSwdenk
972b37c7e5eSwdenk		Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
973b37c7e5eSwdenk		sets the cpu up as a master node and so its address should
974b37c7e5eSwdenk		therefore be cleared to 0 (See, eg, MPC823e User's Manual
975b37c7e5eSwdenk		p.16-473). So, set CFG_I2C_SLAVE to 0.
976b37c7e5eSwdenk
977b37c7e5eSwdenk		That's all that's required for CONFIG_HARD_I2C.
978b37c7e5eSwdenk
979b37c7e5eSwdenk		If you use the software i2c interface (CONFIG_SOFT_I2C)
980b37c7e5eSwdenk		then the following macros need to be defined (examples are
981b37c7e5eSwdenk		from include/configs/lwmon.h):
982c609719bSwdenk
983c609719bSwdenk		I2C_INIT
984c609719bSwdenk
985b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
986c609719bSwdenk		controller or configure ports.
987c609719bSwdenk
988b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
989b37c7e5eSwdenk
990c609719bSwdenk		I2C_PORT
991c609719bSwdenk
992c609719bSwdenk		(Only for MPC8260 CPU). The I/O port to use (the code
993c609719bSwdenk		assumes both bits are on the same port). Valid values
994c609719bSwdenk		are 0..3 for ports A..D.
995c609719bSwdenk
996c609719bSwdenk		I2C_ACTIVE
997c609719bSwdenk
998c609719bSwdenk		The code necessary to make the I2C data line active
999c609719bSwdenk		(driven).  If the data line is open collector, this
1000c609719bSwdenk		define can be null.
1001c609719bSwdenk
1002b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
1003b37c7e5eSwdenk
1004c609719bSwdenk		I2C_TRISTATE
1005c609719bSwdenk
1006c609719bSwdenk		The code necessary to make the I2C data line tri-stated
1007c609719bSwdenk		(inactive).  If the data line is open collector, this
1008c609719bSwdenk		define can be null.
1009c609719bSwdenk
1010b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1011b37c7e5eSwdenk
1012c609719bSwdenk		I2C_READ
1013c609719bSwdenk
1014c609719bSwdenk		Code that returns TRUE if the I2C data line is high,
1015c609719bSwdenk		FALSE if it is low.
1016c609719bSwdenk
1017b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1018b37c7e5eSwdenk
1019c609719bSwdenk		I2C_SDA(bit)
1020c609719bSwdenk
1021c609719bSwdenk		If <bit> is TRUE, sets the I2C data line high. If it
1022c609719bSwdenk		is FALSE, it clears it (low).
1023c609719bSwdenk
1024b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
1025b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
1026b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
1027b37c7e5eSwdenk
1028c609719bSwdenk		I2C_SCL(bit)
1029c609719bSwdenk
1030c609719bSwdenk		If <bit> is TRUE, sets the I2C clock line high. If it
1031c609719bSwdenk		is FALSE, it clears it (low).
1032c609719bSwdenk
1033b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
1034b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
1035b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
1036b37c7e5eSwdenk
1037c609719bSwdenk		I2C_DELAY
1038c609719bSwdenk
1039c609719bSwdenk		This delay is invoked four times per clock cycle so this
1040c609719bSwdenk		controls the rate of data transfer.  The data rate thus
1041b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
1042b37c7e5eSwdenk		like:
1043b37c7e5eSwdenk
1044b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
1045c609719bSwdenk
104647cd00faSwdenk		CFG_I2C_INIT_BOARD
104747cd00faSwdenk
104847cd00faSwdenk		When a board is reset during an i2c bus transfer
104947cd00faSwdenk		chips might think that the current transfer is still
105047cd00faSwdenk		in progress. On some boards it is possible to access
105147cd00faSwdenk		the i2c SCLK line directly, either by using the
105247cd00faSwdenk		processor pin as a GPIO or by having a second pin
105347cd00faSwdenk		connected to the bus. If this option is defined a
105447cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
105547cd00faSwdenk		is run early in the boot sequence.
105647cd00faSwdenk
1057c609719bSwdenk- SPI Support:	CONFIG_SPI
1058c609719bSwdenk
1059c609719bSwdenk		Enables SPI driver (so far only tested with
1060c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
1061c609719bSwdenk		D/As on the SACSng board)
1062c609719bSwdenk
1063c609719bSwdenk		CONFIG_SPI_X
1064c609719bSwdenk
1065c609719bSwdenk		Enables extended (16-bit) SPI EEPROM addressing.
1066c609719bSwdenk		(symmetrical to CONFIG_I2C_X)
1067c609719bSwdenk
1068c609719bSwdenk		CONFIG_SOFT_SPI
1069c609719bSwdenk
1070c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
1071c609719bSwdenk		using hardware support. This is a general purpose
1072c609719bSwdenk		driver that only requires three general I/O port pins
1073c609719bSwdenk		(two outputs, one input) to function. If this is
1074c609719bSwdenk		defined, the board configuration must define several
1075c609719bSwdenk		SPI configuration items (port pins to use, etc). For
1076c609719bSwdenk		an example, see include/configs/sacsng.h.
1077c609719bSwdenk
1078c609719bSwdenk- FPGA Support: CONFIG_FPGA_COUNT
1079c609719bSwdenk
1080c609719bSwdenk		Specify the number of FPGA devices to support.
1081c609719bSwdenk
1082c609719bSwdenk		CONFIG_FPGA
1083c609719bSwdenk
1084c609719bSwdenk		Used to specify the types of FPGA devices.  For example,
1085c609719bSwdenk		#define CONFIG_FPGA  CFG_XILINX_VIRTEX2
1086c609719bSwdenk
1087c609719bSwdenk		CFG_FPGA_PROG_FEEDBACK
1088c609719bSwdenk
1089c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
1090c609719bSwdenk
1091c609719bSwdenk		CFG_FPGA_CHECK_BUSY
1092c609719bSwdenk
1093c609719bSwdenk		Enable checks on FPGA configuration interface busy
1094c609719bSwdenk		status by the configuration function. This option
1095c609719bSwdenk		will require a board or device specific function to
1096c609719bSwdenk		be written.
1097c609719bSwdenk
1098c609719bSwdenk		CONFIG_FPGA_DELAY
1099c609719bSwdenk
1100c609719bSwdenk		If defined, a function that provides delays in the FPGA
1101c609719bSwdenk		configuration driver.
1102c609719bSwdenk
1103c609719bSwdenk		CFG_FPGA_CHECK_CTRLC
1104c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
1105c609719bSwdenk
1106c609719bSwdenk		CFG_FPGA_CHECK_ERROR
1107c609719bSwdenk
1108c609719bSwdenk		Check for configuration errors during FPGA bitfile
1109c609719bSwdenk		loading. For example, abort during Virtex II
1110c609719bSwdenk		configuration if the INIT_B line goes low (which
1111c609719bSwdenk		indicated a CRC error).
1112c609719bSwdenk
1113c609719bSwdenk		CFG_FPGA_WAIT_INIT
1114c609719bSwdenk
1115c609719bSwdenk		Maximum time to wait for the INIT_B line to deassert
1116c609719bSwdenk		after PROB_B has been deasserted during a Virtex II
1117c609719bSwdenk		FPGA configuration sequence. The default time is 500
1118c609719bSwdenk		mS.
1119c609719bSwdenk
1120c609719bSwdenk		CFG_FPGA_WAIT_BUSY
1121c609719bSwdenk
1122c609719bSwdenk		Maximum time to wait for BUSY to deassert during
1123c609719bSwdenk		Virtex II FPGA configuration. The default is 5 mS.
1124c609719bSwdenk
1125c609719bSwdenk		CFG_FPGA_WAIT_CONFIG
1126c609719bSwdenk
1127c609719bSwdenk		Time to wait after FPGA configuration. The default is
1128c609719bSwdenk		200 mS.
1129c609719bSwdenk
1130c609719bSwdenk- Configuration Management:
1131c609719bSwdenk		CONFIG_IDENT_STRING
1132c609719bSwdenk
1133c609719bSwdenk		If defined, this string will be added to the U-Boot
1134c609719bSwdenk		version information (U_BOOT_VERSION)
1135c609719bSwdenk
1136c609719bSwdenk- Vendor Parameter Protection:
1137c609719bSwdenk
1138c609719bSwdenk		U-Boot considers the values of the environment
1139c609719bSwdenk		variables "serial#" (Board Serial Number) and
11407152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
1141c609719bSwdenk		are set once by the board vendor / manufacturer, and
1142c609719bSwdenk		protects these variables from casual modification by
1143c609719bSwdenk		the user. Once set, these variables are read-only,
1144c609719bSwdenk		and write or delete attempts are rejected. You can
1145c609719bSwdenk		change this behviour:
1146c609719bSwdenk
1147c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
1148c609719bSwdenk		file, the write protection for vendor parameters is
114947cd00faSwdenk		completely disabled. Anybody can change or delete
1150c609719bSwdenk		these parameters.
1151c609719bSwdenk
1152c609719bSwdenk		Alternatively, if you #define _both_ CONFIG_ETHADDR
1153c609719bSwdenk		_and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1154c609719bSwdenk		ethernet address is installed in the environment,
1155c609719bSwdenk		which can be changed exactly ONCE by the user. [The
1156c609719bSwdenk		serial# is unaffected by this, i. e. it remains
1157c609719bSwdenk		read-only.]
1158c609719bSwdenk
1159c609719bSwdenk- Protected RAM:
1160c609719bSwdenk		CONFIG_PRAM
1161c609719bSwdenk
1162c609719bSwdenk		Define this variable to enable the reservation of
1163c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
1164c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
1165c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
1166c609719bSwdenk		this default value by defining an environment
1167c609719bSwdenk		variable "pram" to the number of kB you want to
1168c609719bSwdenk		reserve. Note that the board info structure will
1169c609719bSwdenk		still show the full amount of RAM. If pRAM is
1170c609719bSwdenk		reserved, a new environment variable "mem" will
1171c609719bSwdenk		automatically be defined to hold the amount of
1172c609719bSwdenk		remaining RAM in a form that can be passed as boot
1173c609719bSwdenk		argument to Linux, for instance like that:
1174c609719bSwdenk
1175c609719bSwdenk			setenv bootargs ... mem=\$(mem)
1176c609719bSwdenk			saveenv
1177c609719bSwdenk
1178c609719bSwdenk		This way you can tell Linux not to use this memory,
1179c609719bSwdenk		either, which results in a memory region that will
1180c609719bSwdenk		not be affected by reboots.
1181c609719bSwdenk
1182c609719bSwdenk		*WARNING* If your board configuration uses automatic
1183c609719bSwdenk		detection of the RAM size, you must make sure that
1184c609719bSwdenk		this memory test is non-destructive. So far, the
1185c609719bSwdenk		following board configurations are known to be
1186c609719bSwdenk		"pRAM-clean":
1187c609719bSwdenk
1188c609719bSwdenk			ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1189c609719bSwdenk			HERMES, IP860, RPXlite, LWMON, LANTEC,
1190c609719bSwdenk			PCU_E, FLAGADM, TQM8260
1191c609719bSwdenk
1192c609719bSwdenk- Error Recovery:
1193c609719bSwdenk		CONFIG_PANIC_HANG
1194c609719bSwdenk
1195c609719bSwdenk		Define this variable to stop the system in case of a
1196c609719bSwdenk		fatal error, so that you have to reset it manually.
1197c609719bSwdenk		This is probably NOT a good idea for an embedded
1198c609719bSwdenk		system where you want to system to reboot
1199c609719bSwdenk		automatically as fast as possible, but it may be
1200c609719bSwdenk		useful during development since you can try to debug
1201c609719bSwdenk		the conditions that lead to the situation.
1202c609719bSwdenk
1203c609719bSwdenk		CONFIG_NET_RETRY_COUNT
1204c609719bSwdenk
1205c609719bSwdenk		This variable defines the number of retries for
1206c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
1207c609719bSwdenk		before giving up the operation. If not defined, a
1208c609719bSwdenk		default value of 5 is used.
1209c609719bSwdenk
1210c609719bSwdenk- Command Interpreter:
1211c609719bSwdenk		CFG_HUSH_PARSER
1212c609719bSwdenk
1213c609719bSwdenk		Define this variable to enable the "hush" shell (from
1214c609719bSwdenk		Busybox) as command line interpreter, thus enabling
1215c609719bSwdenk		powerful command line syntax like
1216c609719bSwdenk		if...then...else...fi conditionals or `&&' and '||'
1217c609719bSwdenk		constructs ("shell scripts").
1218c609719bSwdenk
1219c609719bSwdenk		If undefined, you get the old, much simpler behaviour
1220c609719bSwdenk		with a somewhat smaller memory footprint.
1221c609719bSwdenk
1222c609719bSwdenk
1223c609719bSwdenk		CFG_PROMPT_HUSH_PS2
1224c609719bSwdenk
1225c609719bSwdenk		This defines the secondary prompt string, which is
1226c609719bSwdenk		printed when the command interpreter needs more input
1227c609719bSwdenk		to complete a command. Usually "> ".
1228c609719bSwdenk
1229c609719bSwdenk	Note:
1230c609719bSwdenk
1231c609719bSwdenk		In the current implementation, the local variables
1232c609719bSwdenk		space and global environment variables space are
1233c609719bSwdenk		separated. Local variables are those you define by
12343b57fe0aSwdenk		simply typing `name=value'. To access a local
1235c609719bSwdenk		variable later on, you have write `$name' or
12363b57fe0aSwdenk		`${name}'; to execute the contents of a variable
12373b57fe0aSwdenk		directly type `$name' at the command prompt.
1238c609719bSwdenk
1239c609719bSwdenk		Global environment variables are those you use
1240c609719bSwdenk		setenv/printenv to work with. To run a command stored
1241c609719bSwdenk		in such a variable, you need to use the run command,
1242c609719bSwdenk		and you must not use the '$' sign to access them.
1243c609719bSwdenk
1244c609719bSwdenk		To store commands and special characters in a
1245c609719bSwdenk		variable, please use double quotation marks
1246c609719bSwdenk		surrounding the whole text of the variable, instead
1247c609719bSwdenk		of the backslashes before semicolons and special
1248c609719bSwdenk		symbols.
1249c609719bSwdenk
1250a8c7c708Swdenk- Default Environment:
1251c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
1252c609719bSwdenk
1253c609719bSwdenk		Define this to contain any number of null terminated
1254c609719bSwdenk		strings (variable = value pairs) that will be part of
12557152b1d0Swdenk		the default environment compiled into the boot image.
12562262cfeeSwdenk
1257c609719bSwdenk		For example, place something like this in your
1258c609719bSwdenk		board's config file:
1259c609719bSwdenk
1260c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
1261c609719bSwdenk			"myvar1=value1\0" \
1262c609719bSwdenk			"myvar2=value2\0"
1263c609719bSwdenk
1264c609719bSwdenk		Warning: This method is based on knowledge about the
1265c609719bSwdenk		internal format how the environment is stored by the
12662262cfeeSwdenk		U-Boot code. This is NOT an official, exported
1267c609719bSwdenk		interface! Although it is unlikely that this format
12687152b1d0Swdenk		will change soon, there is no guarantee either.
1269c609719bSwdenk		You better know what you are doing here.
1270c609719bSwdenk
1271c609719bSwdenk		Note: overly (ab)use of the default environment is
1272c609719bSwdenk		discouraged. Make sure to check other ways to preset
1273c609719bSwdenk		the environment like the autoscript function or the
1274c609719bSwdenk		boot command first.
1275c609719bSwdenk
1276a8c7c708Swdenk- DataFlash Support:
12772abbe075Swdenk		CONFIG_HAS_DATAFLASH
12782abbe075Swdenk
12792abbe075Swdenk		Defining this option enables DataFlash features and
12802abbe075Swdenk		allows to read/write in Dataflash via the standard
12812abbe075Swdenk		commands cp, md...
12822abbe075Swdenk
12833f85ce27Swdenk- SystemACE Support:
12843f85ce27Swdenk		CONFIG_SYSTEMACE
12853f85ce27Swdenk
12863f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
12873f85ce27Swdenk		chips attached via some sort of local bus. The address
12883f85ce27Swdenk		of the chip must alsh be defined in the
12893f85ce27Swdenk		CFG_SYSTEMACE_BASE macro. For example:
12903f85ce27Swdenk
12913f85ce27Swdenk		#define CONFIG_SYSTEMACE
12923f85ce27Swdenk		#define CFG_SYSTEMACE_BASE 0xf0000000
12933f85ce27Swdenk
12943f85ce27Swdenk		When SystemACE support is added, the "ace" device type
12953f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
12963f85ce27Swdenk
1297a8c7c708Swdenk- Show boot progress:
1298c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
1299c609719bSwdenk
1300c609719bSwdenk		Defining this option allows to add some board-
1301c609719bSwdenk		specific code (calling a user-provided function
1302c609719bSwdenk		"show_boot_progress(int)") that enables you to show
1303c609719bSwdenk		the system's boot progress on some display (for
1304c609719bSwdenk		example, some LED's) on your board. At the moment,
1305c609719bSwdenk		the following checkpoints are implemented:
1306c609719bSwdenk
1307c609719bSwdenk  Arg	Where			When
1308c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
1309c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
1310c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
1311c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
1312c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
1313c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
1314c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
1315c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
1316c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
1317c609719bSwdenk   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi, standalone)
1318c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
1319c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
1320c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
1321c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
1322c609719bSwdenk   -8	common/cmd_bootm.c	Wrong Image Type (not kernel, multi, standalone)
1323c609719bSwdenk    8	common/cmd_bootm.c	Image Type check OK
1324c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
1325c609719bSwdenk    9	common/cmd_bootm.c	Start initial ramdisk verification
1326c609719bSwdenk  -10	common/cmd_bootm.c	Ramdisk header has bad	   magic number
1327c609719bSwdenk  -11	common/cmd_bootm.c	Ramdisk header has bad	   checksum
1328c609719bSwdenk   10	common/cmd_bootm.c	Ramdisk header is OK
1329c609719bSwdenk  -12	common/cmd_bootm.c	Ramdisk data   has bad	   checksum
1330c609719bSwdenk   11	common/cmd_bootm.c	Ramdisk data   has correct checksum
1331c609719bSwdenk   12	common/cmd_bootm.c	Ramdisk verification complete, start loading
1332c609719bSwdenk  -13	common/cmd_bootm.c	Wrong Image Type (not PPC Linux Ramdisk)
1333c609719bSwdenk   13	common/cmd_bootm.c	Start multifile image verification
1334c609719bSwdenk   14	common/cmd_bootm.c	No initial ramdisk, no multifile, continue.
1335c609719bSwdenk   15	common/cmd_bootm.c	All preparation done, transferring control to OS
1336c609719bSwdenk
133763e73c9aSwdenk  -30	lib_ppc/board.c		Fatal error, hang the system
133863e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
133963e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
134063e73c9aSwdenk
1341c609719bSwdenk   -1	common/cmd_doc.c	Bad usage of "doc" command
1342c609719bSwdenk   -1	common/cmd_doc.c	No boot device
1343c609719bSwdenk   -1	common/cmd_doc.c	Unknown Chip ID on boot device
1344c609719bSwdenk   -1	common/cmd_doc.c	Read Error on boot device
1345c609719bSwdenk   -1	common/cmd_doc.c	Image header has bad magic number
1346c609719bSwdenk
1347c609719bSwdenk   -1	common/cmd_ide.c	Bad usage of "ide" command
1348c609719bSwdenk   -1	common/cmd_ide.c	No boot device
1349c609719bSwdenk   -1	common/cmd_ide.c	Unknown boot device
1350c609719bSwdenk   -1	common/cmd_ide.c	Unknown partition table
1351c609719bSwdenk   -1	common/cmd_ide.c	Invalid partition type
1352c609719bSwdenk   -1	common/cmd_ide.c	Read Error on boot device
1353c609719bSwdenk   -1	common/cmd_ide.c	Image header has bad magic number
1354c609719bSwdenk
1355206c60cbSwdenk   -1	common/cmd_nand.c	Bad usage of "nand" command
1356206c60cbSwdenk   -1	common/cmd_nand.c	No boot device
1357206c60cbSwdenk   -1	common/cmd_nand.c	Unknown Chip ID on boot device
1358206c60cbSwdenk   -1	common/cmd_nand.c	Read Error on boot device
1359206c60cbSwdenk   -1	common/cmd_nand.c	Image header has bad magic number
1360206c60cbSwdenk
1361206c60cbSwdenk   -1	common/env_common.c	Environment has a bad CRC, using default
1362c609719bSwdenk
1363c609719bSwdenk
1364c609719bSwdenkModem Support:
1365c609719bSwdenk--------------
1366c609719bSwdenk
136785ec0bccSwdenk[so far only for SMDK2400 and TRAB boards]
1368c609719bSwdenk
1369c609719bSwdenk- Modem support endable:
1370c609719bSwdenk		CONFIG_MODEM_SUPPORT
1371c609719bSwdenk
1372c609719bSwdenk- RTS/CTS Flow control enable:
1373c609719bSwdenk		CONFIG_HWFLOW
1374c609719bSwdenk
1375c609719bSwdenk- Modem debug support:
1376c609719bSwdenk		CONFIG_MODEM_SUPPORT_DEBUG
1377c609719bSwdenk
1378c609719bSwdenk		Enables debugging stuff (char screen[1024], dbg())
1379c609719bSwdenk		for modem support. Useful only with BDI2000.
1380c609719bSwdenk
1381a8c7c708Swdenk- Interrupt support (PPC):
1382a8c7c708Swdenk
1383a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
1384a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1385a8c7c708Swdenk		for cpu specific initialization. interrupt_init_cpu()
1386a8c7c708Swdenk		should set decrementer_count to appropriate value. If
1387a8c7c708Swdenk		cpu resets decrementer automatically after interrupt
1388a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
1389a8c7c708Swdenk		timer_interrupt() calls timer_interrupt_cpu() for cpu
1390a8c7c708Swdenk		specific handling. If board has watchdog / status_led
1391a8c7c708Swdenk		/ other_activity_monitor it works automatically from
1392a8c7c708Swdenk		general timer_interrupt().
1393a8c7c708Swdenk
1394c609719bSwdenk- General:
1395c609719bSwdenk
1396c609719bSwdenk		In the target system modem support is enabled when a
1397c609719bSwdenk		specific key (key combination) is pressed during
1398c609719bSwdenk		power-on. Otherwise U-Boot will boot normally
1399c609719bSwdenk		(autoboot). The key_pressed() fuction is called from
1400c609719bSwdenk		board_init(). Currently key_pressed() is a dummy
1401c609719bSwdenk		function, returning 1 and thus enabling modem
1402c609719bSwdenk		initialization.
1403c609719bSwdenk
1404c609719bSwdenk		If there are no modem init strings in the
1405c609719bSwdenk		environment, U-Boot proceed to autoboot; the
1406c609719bSwdenk		previous output (banner, info printfs) will be
1407c609719bSwdenk		supressed, though.
1408c609719bSwdenk
1409c609719bSwdenk		See also: doc/README.Modem
1410c609719bSwdenk
1411c609719bSwdenk
1412c609719bSwdenkConfiguration Settings:
1413c609719bSwdenk-----------------------
1414c609719bSwdenk
1415c609719bSwdenk- CFG_LONGHELP: Defined when you want long help messages included;
1416c609719bSwdenk		undefine this when you're short of memory.
1417c609719bSwdenk
1418c609719bSwdenk- CFG_PROMPT:	This is what U-Boot prints on the console to
1419c609719bSwdenk		prompt for user input.
1420c609719bSwdenk
1421c609719bSwdenk- CFG_CBSIZE:	Buffer size for input from the Console
1422c609719bSwdenk
1423c609719bSwdenk- CFG_PBSIZE:	Buffer size for Console output
1424c609719bSwdenk
1425c609719bSwdenk- CFG_MAXARGS:	max. Number of arguments accepted for monitor commands
1426c609719bSwdenk
1427c609719bSwdenk- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1428c609719bSwdenk		the application (usually a Linux kernel) when it is
1429c609719bSwdenk		booted
1430c609719bSwdenk
1431c609719bSwdenk- CFG_BAUDRATE_TABLE:
1432c609719bSwdenk		List of legal baudrate settings for this board.
1433c609719bSwdenk
1434c609719bSwdenk- CFG_CONSOLE_INFO_QUIET
1435c609719bSwdenk		Suppress display of console information at boot.
1436c609719bSwdenk
1437c609719bSwdenk- CFG_CONSOLE_IS_IN_ENV
1438c609719bSwdenk		If the board specific function
1439c609719bSwdenk			extern int overwrite_console (void);
1440c609719bSwdenk		returns 1, the stdin, stderr and stdout are switched to the
1441c609719bSwdenk		serial port, else the settings in the environment are used.
1442c609719bSwdenk
1443c609719bSwdenk- CFG_CONSOLE_OVERWRITE_ROUTINE
1444c609719bSwdenk		Enable the call to overwrite_console().
1445c609719bSwdenk
1446c609719bSwdenk- CFG_CONSOLE_ENV_OVERWRITE
1447c609719bSwdenk		Enable overwrite of previous console environment settings.
1448c609719bSwdenk
1449c609719bSwdenk- CFG_MEMTEST_START, CFG_MEMTEST_END:
1450c609719bSwdenk		Begin and End addresses of the area used by the
1451c609719bSwdenk		simple memory test.
1452c609719bSwdenk
1453c609719bSwdenk- CFG_ALT_MEMTEST:
1454c609719bSwdenk		Enable an alternate, more extensive memory test.
1455c609719bSwdenk
14565f535fe1Swdenk- CFG_MEMTEST_SCRATCH:
14575f535fe1Swdenk		Scratch address used by the alternate memory test
14585f535fe1Swdenk		You only need to set this if address zero isn't writeable
14595f535fe1Swdenk
1460c609719bSwdenk- CFG_TFTP_LOADADDR:
1461c609719bSwdenk		Default load address for network file downloads
1462c609719bSwdenk
1463c609719bSwdenk- CFG_LOADS_BAUD_CHANGE:
1464c609719bSwdenk		Enable temporary baudrate change while serial download
1465c609719bSwdenk
1466c609719bSwdenk- CFG_SDRAM_BASE:
1467c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
1468c609719bSwdenk
1469c609719bSwdenk- CFG_MBIO_BASE:
1470c609719bSwdenk		Physical start address of Motherboard I/O (if using a
1471c609719bSwdenk		Cogent motherboard)
1472c609719bSwdenk
1473c609719bSwdenk- CFG_FLASH_BASE:
1474c609719bSwdenk		Physical start address of Flash memory.
1475c609719bSwdenk
1476c609719bSwdenk- CFG_MONITOR_BASE:
1477c609719bSwdenk		Physical start address of boot monitor code (set by
1478c609719bSwdenk		make config files to be same as the text base address
1479c609719bSwdenk		(TEXT_BASE) used when linking) - same as
1480c609719bSwdenk		CFG_FLASH_BASE when booting from flash.
1481c609719bSwdenk
1482c609719bSwdenk- CFG_MONITOR_LEN:
14833b57fe0aSwdenk		Size of memory reserved for monitor code, used to
14843b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
14853b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
14863b57fe0aSwdenk		flash sector.
1487c609719bSwdenk
1488c609719bSwdenk- CFG_MALLOC_LEN:
1489c609719bSwdenk		Size of DRAM reserved for malloc() use.
1490c609719bSwdenk
1491c609719bSwdenk- CFG_BOOTMAPSZ:
1492c609719bSwdenk		Maximum size of memory mapped by the startup code of
1493c609719bSwdenk		the Linux kernel; all data that must be processed by
1494c609719bSwdenk		the Linux kernel (bd_info, boot arguments, eventually
1495c609719bSwdenk		initrd image) must be put below this limit.
1496c609719bSwdenk
1497c609719bSwdenk- CFG_MAX_FLASH_BANKS:
1498c609719bSwdenk		Max number of Flash memory banks
1499c609719bSwdenk
1500c609719bSwdenk- CFG_MAX_FLASH_SECT:
1501c609719bSwdenk		Max number of sectors on a Flash chip
1502c609719bSwdenk
1503c609719bSwdenk- CFG_FLASH_ERASE_TOUT:
1504c609719bSwdenk		Timeout for Flash erase operations (in ms)
1505c609719bSwdenk
1506c609719bSwdenk- CFG_FLASH_WRITE_TOUT:
1507c609719bSwdenk		Timeout for Flash write operations (in ms)
1508c609719bSwdenk
15098564acf9Swdenk- CFG_FLASH_LOCK_TOUT
15108564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
15118564acf9Swdenk
15128564acf9Swdenk- CFG_FLASH_UNLOCK_TOUT
15138564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
15148564acf9Swdenk
15158564acf9Swdenk- CFG_FLASH_PROTECTION
15168564acf9Swdenk		If defined, hardware flash sectors protection is used
15178564acf9Swdenk		instead of U-Boot software protection.
15188564acf9Swdenk
1519c609719bSwdenk- CFG_DIRECT_FLASH_TFTP:
1520c609719bSwdenk
1521c609719bSwdenk		Enable TFTP transfers directly to flash memory;
1522c609719bSwdenk		without this option such a download has to be
1523c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
1524c609719bSwdenk		copy from RAM to flash.
1525c609719bSwdenk
1526c609719bSwdenk		The two-step approach is usually more reliable, since
1527c609719bSwdenk		you can check if the download worked before you erase
1528c609719bSwdenk		the flash, but in some situations (when sytem RAM is
1529c609719bSwdenk		too limited to allow for a tempory copy of the
1530c609719bSwdenk		downloaded image) this option may be very useful.
1531c609719bSwdenk
1532c609719bSwdenk- CFG_FLASH_CFI:
1533c609719bSwdenk		Define if the flash driver uses extra elements in the
15345653fc33Swdenk		common flash structure for storing flash geometry.
15355653fc33Swdenk
15365653fc33Swdenk- CFG_FLASH_CFI_DRIVER
15375653fc33Swdenk		This option also enables the building of the cfi_flash driver
15385653fc33Swdenk		in the drivers directory
153953cf9435Sstroese
154053cf9435Sstroese- CFG_RX_ETH_BUFFER:
154153cf9435Sstroese		Defines the number of ethernet receive buffers. On some
154253cf9435Sstroese		ethernet controllers it is recommended to set this value
154353cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
154453cf9435Sstroese		buffers can be full shortly after enabling the interface
154553cf9435Sstroese		on high ethernet traffic.
154653cf9435Sstroese		Defaults to 4 if not defined.
1547c609719bSwdenk
1548c609719bSwdenkThe following definitions that deal with the placement and management
1549c609719bSwdenkof environment data (variable area); in general, we support the
1550c609719bSwdenkfollowing configurations:
1551c609719bSwdenk
1552c609719bSwdenk- CFG_ENV_IS_IN_FLASH:
1553c609719bSwdenk
1554c609719bSwdenk	Define this if the environment is in flash memory.
1555c609719bSwdenk
1556c609719bSwdenk	a) The environment occupies one whole flash sector, which is
1557c609719bSwdenk	   "embedded" in the text segment with the U-Boot code. This
1558c609719bSwdenk	   happens usually with "bottom boot sector" or "top boot
1559c609719bSwdenk	   sector" type flash chips, which have several smaller
1560c609719bSwdenk	   sectors at the start or the end. For instance, such a
1561c609719bSwdenk	   layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1562c609719bSwdenk	   such a case you would place the environment in one of the
1563c609719bSwdenk	   4 kB sectors - with U-Boot code before and after it. With
1564c609719bSwdenk	   "top boot sector" type flash chips, you would put the
1565c609719bSwdenk	   environment in one of the last sectors, leaving a gap
1566c609719bSwdenk	   between U-Boot and the environment.
1567c609719bSwdenk
1568c609719bSwdenk	- CFG_ENV_OFFSET:
1569c609719bSwdenk
1570c609719bSwdenk	   Offset of environment data (variable area) to the
1571c609719bSwdenk	   beginning of flash memory; for instance, with bottom boot
1572c609719bSwdenk	   type flash chips the second sector can be used: the offset
1573c609719bSwdenk	   for this sector is given here.
1574c609719bSwdenk
1575c609719bSwdenk	   CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1576c609719bSwdenk
1577c609719bSwdenk	- CFG_ENV_ADDR:
1578c609719bSwdenk
1579c609719bSwdenk	   This is just another way to specify the start address of
1580c609719bSwdenk	   the flash sector containing the environment (instead of
1581c609719bSwdenk	   CFG_ENV_OFFSET).
1582c609719bSwdenk
1583c609719bSwdenk	- CFG_ENV_SECT_SIZE:
1584c609719bSwdenk
1585c609719bSwdenk	   Size of the sector containing the environment.
1586c609719bSwdenk
1587c609719bSwdenk
1588c609719bSwdenk	b) Sometimes flash chips have few, equal sized, BIG sectors.
1589c609719bSwdenk	   In such a case you don't want to spend a whole sector for
1590c609719bSwdenk	   the environment.
1591c609719bSwdenk
1592c609719bSwdenk	- CFG_ENV_SIZE:
1593c609719bSwdenk
1594c609719bSwdenk	   If you use this in combination with CFG_ENV_IS_IN_FLASH
1595c609719bSwdenk	   and CFG_ENV_SECT_SIZE, you can specify to use only a part
1596c609719bSwdenk	   of this flash sector for the environment. This saves
1597c609719bSwdenk	   memory for the RAM copy of the environment.
1598c609719bSwdenk
1599c609719bSwdenk	   It may also save flash memory if you decide to use this
1600c609719bSwdenk	   when your environment is "embedded" within U-Boot code,
1601c609719bSwdenk	   since then the remainder of the flash sector could be used
1602c609719bSwdenk	   for U-Boot code. It should be pointed out that this is
1603c609719bSwdenk	   STRONGLY DISCOURAGED from a robustness point of view:
1604c609719bSwdenk	   updating the environment in flash makes it always
1605c609719bSwdenk	   necessary to erase the WHOLE sector. If something goes
1606c609719bSwdenk	   wrong before the contents has been restored from a copy in
1607c609719bSwdenk	   RAM, your target system will be dead.
1608c609719bSwdenk
1609c609719bSwdenk	- CFG_ENV_ADDR_REDUND
1610c609719bSwdenk	  CFG_ENV_SIZE_REDUND
1611c609719bSwdenk
1612c609719bSwdenk	   These settings describe a second storage area used to hold
1613c609719bSwdenk	   a redundand copy of the environment data, so that there is
16143e38691eSwdenk	   a valid backup copy in case there is a power failure during
1615c609719bSwdenk	   a "saveenv" operation.
1616c609719bSwdenk
1617c609719bSwdenkBE CAREFUL! Any changes to the flash layout, and some changes to the
1618c609719bSwdenksource code will make it necessary to adapt <board>/u-boot.lds*
1619c609719bSwdenkaccordingly!
1620c609719bSwdenk
1621c609719bSwdenk
1622c609719bSwdenk- CFG_ENV_IS_IN_NVRAM:
1623c609719bSwdenk
1624c609719bSwdenk	Define this if you have some non-volatile memory device
1625c609719bSwdenk	(NVRAM, battery buffered SRAM) which you want to use for the
1626c609719bSwdenk	environment.
1627c609719bSwdenk
1628c609719bSwdenk	- CFG_ENV_ADDR:
1629c609719bSwdenk	- CFG_ENV_SIZE:
1630c609719bSwdenk
1631c609719bSwdenk	  These two #defines are used to determin the memory area you
1632c609719bSwdenk	  want to use for environment. It is assumed that this memory
1633c609719bSwdenk	  can just be read and written to, without any special
1634c609719bSwdenk	  provision.
1635c609719bSwdenk
1636c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
1637c609719bSwdenkin U-Boot initalization (when we try to get the setting of for the
1638c609719bSwdenkconsole baudrate). You *MUST* have mappend your NVRAM area then, or
1639c609719bSwdenkU-Boot will hang.
1640c609719bSwdenk
1641c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
1642c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
1643c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
1644c609719bSwdenkto save the current settings.
1645c609719bSwdenk
1646c609719bSwdenk
1647c609719bSwdenk- CFG_ENV_IS_IN_EEPROM:
1648c609719bSwdenk
1649c609719bSwdenk	Use this if you have an EEPROM or similar serial access
1650c609719bSwdenk	device and a driver for it.
1651c609719bSwdenk
1652c609719bSwdenk	- CFG_ENV_OFFSET:
1653c609719bSwdenk	- CFG_ENV_SIZE:
1654c609719bSwdenk
1655c609719bSwdenk	  These two #defines specify the offset and size of the
1656c609719bSwdenk	  environment area within the total memory of your EEPROM.
1657c609719bSwdenk
1658c609719bSwdenk	- CFG_I2C_EEPROM_ADDR:
1659c609719bSwdenk	  If defined, specified the chip address of the EEPROM device.
1660c609719bSwdenk	  The default address is zero.
1661c609719bSwdenk
1662c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_BITS:
1663c609719bSwdenk	  If defined, the number of bits used to address bytes in a
1664c609719bSwdenk	  single page in the EEPROM device.  A 64 byte page, for example
1665c609719bSwdenk	  would require six bits.
1666c609719bSwdenk
1667c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1668c609719bSwdenk	  If defined, the number of milliseconds to delay between
1669c609719bSwdenk	  page writes.	The default is zero milliseconds.
1670c609719bSwdenk
1671c609719bSwdenk	- CFG_I2C_EEPROM_ADDR_LEN:
1672c609719bSwdenk	  The length in bytes of the EEPROM memory array address.  Note
1673c609719bSwdenk	  that this is NOT the chip address length!
1674c609719bSwdenk
1675c609719bSwdenk	- CFG_EEPROM_SIZE:
1676c609719bSwdenk	  The size in bytes of the EEPROM device.
1677c609719bSwdenk
1678c609719bSwdenk
16795779d8d9Swdenk- CFG_ENV_IS_IN_DATAFLASH:
16805779d8d9Swdenk
16815779d8d9Swdenk	Define this if you have a DataFlash memory device which you
16825779d8d9Swdenk	want to use for the environment.
16835779d8d9Swdenk
16845779d8d9Swdenk	- CFG_ENV_OFFSET:
16855779d8d9Swdenk	- CFG_ENV_ADDR:
16865779d8d9Swdenk	- CFG_ENV_SIZE:
16875779d8d9Swdenk
16885779d8d9Swdenk	  These three #defines specify the offset and size of the
16895779d8d9Swdenk	  environment area within the total memory of your DataFlash placed
16905779d8d9Swdenk	  at the specified address.
16915779d8d9Swdenk
16925779d8d9Swdenk
1693c609719bSwdenk- CFG_SPI_INIT_OFFSET
1694c609719bSwdenk
1695c609719bSwdenk	Defines offset to the initial SPI buffer area in DPRAM. The
1696c609719bSwdenk	area is used at an early stage (ROM part) if the environment
1697c609719bSwdenk	is configured to reside in the SPI EEPROM: We need a 520 byte
1698c609719bSwdenk	scratch DPRAM area. It is used between the two initialization
1699c609719bSwdenk	calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1700c609719bSwdenk	to be a good choice since it makes it far enough from the
1701c609719bSwdenk	start of the data area as well as from the stack pointer.
1702c609719bSwdenk
1703c609719bSwdenkPlease note that the environment is read-only as long as the monitor
1704c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
1705c609719bSwdenkcreated; also, when using EEPROM you will have to use getenv_r()
1706c609719bSwdenkuntil then to read environment variables.
1707c609719bSwdenk
170885ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
170985ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
171085ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
171185ec0bccSwdenknecessary, because the first environment variable we need is the
171285ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
171385ec0bccSwdenkhave any device yet where we could complain.]
1714c609719bSwdenk
1715c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
1716c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
171785ec0bccSwdenkuse the "saveenv" command to store a valid environment.
1718c609719bSwdenk
1719fc3e2165Swdenk- CFG_FAULT_ECHO_LINK_DOWN:
1720fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
1721fc3e2165Swdenk
1722fc3e2165Swdenk		Note: If this option is active, then CFG_FAULT_MII_ADDR
1723fc3e2165Swdenk		      also needs to be defined.
1724fc3e2165Swdenk
1725fc3e2165Swdenk- CFG_FAULT_MII_ADDR:
1726fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
1727c609719bSwdenk
1728*c40b2956Swdenk- CFG_64BIT_VSPRINTF:
1729*c40b2956Swdenk		Makes vsprintf (and all *printf functions) support printing
1730*c40b2956Swdenk		of 64bit values by using the L quantifier
1731*c40b2956Swdenk
1732*c40b2956Swdenk- CFG_64BIT_STRTOUL:
1733*c40b2956Swdenk		Adds simple_strtoull that returns a 64bit value
1734*c40b2956Swdenk
1735c609719bSwdenkLow Level (hardware related) configuration options:
1736dc7c9a1aSwdenk---------------------------------------------------
1737c609719bSwdenk
1738c609719bSwdenk- CFG_CACHELINE_SIZE:
1739c609719bSwdenk		Cache Line Size of the CPU.
1740c609719bSwdenk
1741c609719bSwdenk- CFG_DEFAULT_IMMR:
1742c609719bSwdenk		Default address of the IMMR after system reset.
17432535d602Swdenk
17442535d602Swdenk		Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
17452535d602Swdenk		and RPXsuper) to be able to adjust the position of
17462535d602Swdenk		the IMMR register after a reset.
1747c609719bSwdenk
17487f6c2cbcSwdenk- Floppy Disk Support:
17497f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER
17507f6c2cbcSwdenk
17517f6c2cbcSwdenk		the default drive number (default value 0)
17527f6c2cbcSwdenk
17537f6c2cbcSwdenk		CFG_ISA_IO_STRIDE
17547f6c2cbcSwdenk
17557f6c2cbcSwdenk		defines the spacing between fdc chipset registers
17567f6c2cbcSwdenk		(default value 1)
17577f6c2cbcSwdenk
17587f6c2cbcSwdenk		CFG_ISA_IO_OFFSET
17597f6c2cbcSwdenk
17607f6c2cbcSwdenk		defines the offset of register from address. It
17617f6c2cbcSwdenk		depends on which part of the data bus is connected to
17627f6c2cbcSwdenk		the fdc chipset. (default value 0)
17637f6c2cbcSwdenk
17647f6c2cbcSwdenk		If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
17657f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER are undefined, they take their
17667f6c2cbcSwdenk		default value.
17677f6c2cbcSwdenk
17687f6c2cbcSwdenk		if CFG_FDC_HW_INIT is defined, then the function
17697f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
17707f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
17717f6c2cbcSwdenk		source code. It is used to make hardware dependant
17727f6c2cbcSwdenk		initializations.
17737f6c2cbcSwdenk
1774c609719bSwdenk- CFG_IMMR:	Physical address of the Internal Memory Mapped
1775c609719bSwdenk		Register; DO NOT CHANGE! (11-4)
1776c609719bSwdenk		[MPC8xx systems only]
1777c609719bSwdenk
1778c609719bSwdenk- CFG_INIT_RAM_ADDR:
1779c609719bSwdenk
17807152b1d0Swdenk		Start address of memory area that can be used for
1781c609719bSwdenk		initial data and stack; please note that this must be
1782c609719bSwdenk		writable memory that is working WITHOUT special
1783c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
1784c609719bSwdenk		will become available only after programming the
1785c609719bSwdenk		memory controller and running certain initialization
1786c609719bSwdenk		sequences.
1787c609719bSwdenk
1788c609719bSwdenk		U-Boot uses the following memory types:
1789c609719bSwdenk		- MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1790c609719bSwdenk		- MPC824X: data cache
1791c609719bSwdenk		- PPC4xx:  data cache
1792c609719bSwdenk
179385ec0bccSwdenk- CFG_GBL_DATA_OFFSET:
1794c609719bSwdenk
1795c609719bSwdenk		Offset of the initial data structure in the memory
1796c609719bSwdenk		area defined by CFG_INIT_RAM_ADDR. Usually
179785ec0bccSwdenk		CFG_GBL_DATA_OFFSET is chosen such that the initial
1798c609719bSwdenk		data is located at the end of the available space
1799c609719bSwdenk		(sometimes written as (CFG_INIT_RAM_END -
1800c609719bSwdenk		CFG_INIT_DATA_SIZE), and the initial stack is just
1801c609719bSwdenk		below that area (growing from (CFG_INIT_RAM_ADDR +
180285ec0bccSwdenk		CFG_GBL_DATA_OFFSET) downward.
1803c609719bSwdenk
1804c609719bSwdenk	Note:
1805c609719bSwdenk		On the MPC824X (or other systems that use the data
1806c609719bSwdenk		cache for initial memory) the address chosen for
1807c609719bSwdenk		CFG_INIT_RAM_ADDR is basically arbitrary - it must
1808c609719bSwdenk		point to an otherwise UNUSED address space between
1809c609719bSwdenk		the top of RAM and the start of the PCI space.
1810c609719bSwdenk
1811c609719bSwdenk- CFG_SIUMCR:	SIU Module Configuration (11-6)
1812c609719bSwdenk
1813c609719bSwdenk- CFG_SYPCR:	System Protection Control (11-9)
1814c609719bSwdenk
1815c609719bSwdenk- CFG_TBSCR:	Time Base Status and Control (11-26)
1816c609719bSwdenk
1817c609719bSwdenk- CFG_PISCR:	Periodic Interrupt Status and Control (11-31)
1818c609719bSwdenk
1819c609719bSwdenk- CFG_PLPRCR:	PLL, Low-Power, and Reset Control Register (15-30)
1820c609719bSwdenk
1821c609719bSwdenk- CFG_SCCR:	System Clock and reset Control Register (15-27)
1822c609719bSwdenk
1823c609719bSwdenk- CFG_OR_TIMING_SDRAM:
1824c609719bSwdenk		SDRAM timing
1825c609719bSwdenk
1826c609719bSwdenk- CFG_MAMR_PTA:
1827c609719bSwdenk		periodic timer for refresh
1828c609719bSwdenk
1829c609719bSwdenk- CFG_DER:	Debug Event Register (37-47)
1830c609719bSwdenk
1831c609719bSwdenk- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1832c609719bSwdenk  CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1833c609719bSwdenk  CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1834c609719bSwdenk  CFG_BR1_PRELIM:
1835c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1836c609719bSwdenk
1837c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1838c609719bSwdenk  CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1839c609719bSwdenk  CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1840c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1841c609719bSwdenk
1842c609719bSwdenk- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1843c609719bSwdenk  CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1844c609719bSwdenk		Machine Mode Register and Memory Periodic Timer
1845c609719bSwdenk		Prescaler definitions (SDRAM timing)
1846c609719bSwdenk
1847c609719bSwdenk- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1848c609719bSwdenk		enable I2C microcode relocation patch (MPC8xx);
1849c609719bSwdenk		define relocation offset in DPRAM [DSP2]
1850c609719bSwdenk
1851c609719bSwdenk- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1852c609719bSwdenk		enable SPI microcode relocation patch (MPC8xx);
1853c609719bSwdenk		define relocation offset in DPRAM [SCC4]
1854c609719bSwdenk
1855c609719bSwdenk- CFG_USE_OSCCLK:
1856c609719bSwdenk		Use OSCM clock mode on MBX8xx board. Be careful,
1857c609719bSwdenk		wrong setting might damage your board. Read
1858c609719bSwdenk		doc/README.MBX before setting this variable!
1859c609719bSwdenk
1860ea909b76Swdenk- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1861ea909b76Swdenk		Offset of the bootmode word in DPRAM used by post
1862ea909b76Swdenk		(Power On Self Tests). This definition overrides
1863ea909b76Swdenk		#define'd default value in commproc.h resp.
1864ea909b76Swdenk		cpm_8260.h.
1865ea909b76Swdenk
18665d232d0eSwdenk- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
18675d232d0eSwdenk  CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
18685d232d0eSwdenk  CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
18695d232d0eSwdenk  CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
18705d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
18715d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
18725d232d0eSwdenk  CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
18735d232d0eSwdenk  CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
18745d232d0eSwdenk		Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
18755d232d0eSwdenk
1876c609719bSwdenkBuilding the Software:
1877c609719bSwdenk======================
1878c609719bSwdenk
1879c609719bSwdenkBuilding U-Boot has been tested in native PPC environments (on a
1880c609719bSwdenkPowerBook G3 running LinuxPPC 2000) and in cross environments
1881c609719bSwdenk(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1882c609719bSwdenkNetBSD 1.5 on x86).
1883c609719bSwdenk
1884c609719bSwdenkIf you are not using a native PPC environment, it is assumed that you
1885c609719bSwdenkhave the GNU cross compiling tools available in your path and named
1886c609719bSwdenkwith a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1887c609719bSwdenkyou are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1888c609719bSwdenkthe definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1889c609719bSwdenkchange it to:
1890c609719bSwdenk
1891c609719bSwdenk	CROSS_COMPILE = ppc_4xx-
1892c609719bSwdenk
1893c609719bSwdenk
1894c609719bSwdenkU-Boot is intended to be  simple  to  build.  After  installing	 the
1895c609719bSwdenksources	 you must configure U-Boot for one specific board type. This
1896c609719bSwdenkis done by typing:
1897c609719bSwdenk
1898c609719bSwdenk	make NAME_config
1899c609719bSwdenk
1900c609719bSwdenkwhere "NAME_config" is the name of one of the existing
1901c609719bSwdenkconfigurations; the following names are supported:
1902c609719bSwdenk
1903c609719bSwdenk    ADCIOP_config	  GTH_config		TQM850L_config
1904c609719bSwdenk    ADS860_config	  IP860_config		TQM855L_config
1905c609719bSwdenk    AR405_config	  IVML24_config		TQM860L_config
1906c609719bSwdenk    CANBT_config	  IVMS8_config		WALNUT405_config
1907c609719bSwdenk    CPCI405_config	  LANTEC_config		cogent_common_config
1908c609719bSwdenk    CPCIISER4_config	  MBX_config		cogent_mpc8260_config
1909c609719bSwdenk    CU824_config	  MBX860T_config	cogent_mpc8xx_config
1910c609719bSwdenk    ESTEEM192E_config	  RPXlite_config	hermes_config
1911c609719bSwdenk    ETX094_config	  RPXsuper_config	hymod_config
1912c609719bSwdenk    FADS823_config	  SM850_config		lwmon_config
1913c609719bSwdenk    FADS850SAR_config	  SPD823TS_config	pcu_e_config
1914c609719bSwdenk    FADS860T_config	  SXNI855T_config	rsdproto_config
1915c609719bSwdenk    FPS850L_config	  Sandpoint8240_config	sbc8260_config
1916c609719bSwdenk    GENIETV_config	  TQM823L_config	PIP405_config
1917384ae025Swdenk    GEN860T_config	  EBONY_config		FPS860L_config
19187f70e853Swdenk    ELPT860_config	  cmi_mpc5xx_config	NETVIA_config
19192535d602Swdenk    at91rm9200dk_config	  omap1510inn_config	MPC8260ADS_config
192042d1f039Swdenk    omap1610inn_config	  ZPC1900_config	MPC8540ADS_config
19213bbc899fSwdenk    MPC8560ADS_config	  QS850_config		QS823_config
192263e73c9aSwdenk    QS860T_config	  DUET_ADS_config	omap1610h2_config
192354387ac9Swdenk
1924c609719bSwdenkNote: for some board special configuration names may exist; check  if
1925c609719bSwdenk      additional  information is available from the board vendor; for
1926c609719bSwdenk      instance, the TQM8xxL systems run normally at 50 MHz and use  a
1927c609719bSwdenk      SCC  for	10baseT	 ethernet; there are also systems with 80 MHz
1928c609719bSwdenk      CPU clock, and an optional Fast Ethernet	module	is  available
1929c609719bSwdenk      for  CPU's  with FEC. You can select such additional "features"
1930c609719bSwdenk      when chosing the configuration, i. e.
1931c609719bSwdenk
1932c609719bSwdenk      make TQM860L_config
1933c609719bSwdenk	- will configure for a plain TQM860L, i. e. 50MHz, no FEC
1934c609719bSwdenk
1935c609719bSwdenk      make TQM860L_FEC_config
1936c609719bSwdenk	- will configure for a TQM860L at 50MHz with FEC for ethernet
1937c609719bSwdenk
1938c609719bSwdenk      make TQM860L_80MHz_config
1939c609719bSwdenk	- will configure for a TQM860L at 80 MHz, with normal 10baseT
1940c609719bSwdenk	  interface
1941c609719bSwdenk
1942c609719bSwdenk      make TQM860L_FEC_80MHz_config
1943c609719bSwdenk	- will configure for a TQM860L at 80 MHz with FEC for ethernet
1944c609719bSwdenk
1945c609719bSwdenk      make TQM823L_LCD_config
1946c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
1947c609719bSwdenk
1948c609719bSwdenk      make TQM823L_LCD_80MHz_config
1949c609719bSwdenk	- will configure for a TQM823L at 80 MHz with U-Boot console on LCD
1950c609719bSwdenk
1951c609719bSwdenk      etc.
1952c609719bSwdenk
1953c609719bSwdenk
1954c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
19557152b1d0Swdenkimages ready for download to / installation on your system:
1956c609719bSwdenk
1957c609719bSwdenk- "u-boot.bin" is a raw binary image
1958c609719bSwdenk- "u-boot" is an image in ELF binary format
1959c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
1960c609719bSwdenk
1961c609719bSwdenk
1962c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
1963c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
1964c609719bSwdenknative "make".
1965c609719bSwdenk
1966c609719bSwdenk
1967c609719bSwdenkIf the system board that you have is not listed, then you will need
1968c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
1969c609719bSwdenksteps:
1970c609719bSwdenk
1971c609719bSwdenk1.  Add a new configuration option for your board to the toplevel
197285ec0bccSwdenk    "Makefile" and to the "MAKEALL" script, using the existing
197385ec0bccSwdenk    entries as examples. Note that here and at many other places
19747152b1d0Swdenk    boards and other names are listed in alphabetical sort order. Please
197585ec0bccSwdenk    keep this order.
1976c609719bSwdenk2.  Create a new directory to hold your board specific code. Add any
197785ec0bccSwdenk    files you need. In your board directory, you will need at least
197885ec0bccSwdenk    the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
197985ec0bccSwdenk3.  Create a new configuration file "include/configs/<board>.h" for
198085ec0bccSwdenk    your board
1981c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
1982c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
198385ec0bccSwdenk4.  Run "make <board>_config" with your new name.
1984c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
1985c609719bSwdenk    to be installed on your target system.
198685ec0bccSwdenk6.  Debug and solve any problems that might arise.
1987c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
1988c609719bSwdenk
1989c609719bSwdenk
1990c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
1991c609719bSwdenk==============================================================
1992c609719bSwdenk
1993c609719bSwdenkIf you have modified U-Boot sources (for instance added a new	board
1994c609719bSwdenkor  support  for  new  devices,	 a new CPU, etc.) you are expected to
1995c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
1996c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
1997c609719bSwdenkofficial or latest in CVS) version of U-Boot sources.
1998c609719bSwdenk
1999c609719bSwdenkBut before you submit such a patch, please verify that	your  modifi-
2000c609719bSwdenkcation	did not break existing code. At least make sure that *ALL* of
2001c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
2002c609719bSwdenkjust run the "MAKEALL" script, which will configure and build U-Boot
2003c609719bSwdenkfor ALL supported system. Be warned, this will take a while. You  can
20047152b1d0Swdenkselect	which  (cross)	compiler  to use by passing a `CROSS_COMPILE'
2005c609719bSwdenkenvironment variable to the script, i. e. to use the cross tools from
2006c609719bSwdenkMontaVista's Hard Hat Linux you can type
2007c609719bSwdenk
2008c609719bSwdenk	CROSS_COMPILE=ppc_8xx- MAKEALL
2009c609719bSwdenk
2010c609719bSwdenkor to build on a native PowerPC system you can type
2011c609719bSwdenk
2012c609719bSwdenk	CROSS_COMPILE=' ' MAKEALL
2013c609719bSwdenk
2014c609719bSwdenkSee also "U-Boot Porting Guide" below.
2015c609719bSwdenk
2016c609719bSwdenk
2017c609719bSwdenkMonitor Commands - Overview:
2018c609719bSwdenk============================
2019c609719bSwdenk
2020c609719bSwdenkgo	- start application at address 'addr'
2021c609719bSwdenkrun	- run commands in an environment variable
2022c609719bSwdenkbootm	- boot application image from memory
2023c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
2024c609719bSwdenktftpboot- boot image via network using TFTP protocol
2025c609719bSwdenk	       and env variables "ipaddr" and "serverip"
2026c609719bSwdenk	       (and eventually "gatewayip")
2027c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
2028c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
2029c609719bSwdenkloads	- load S-Record file over serial line
2030c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
2031c609719bSwdenkmd	- memory display
2032c609719bSwdenkmm	- memory modify (auto-incrementing)
2033c609719bSwdenknm	- memory modify (constant address)
2034c609719bSwdenkmw	- memory write (fill)
2035c609719bSwdenkcp	- memory copy
2036c609719bSwdenkcmp	- memory compare
2037c609719bSwdenkcrc32	- checksum calculation
2038c609719bSwdenkimd	- i2c memory display
2039c609719bSwdenkimm	- i2c memory modify (auto-incrementing)
2040c609719bSwdenkinm	- i2c memory modify (constant address)
2041c609719bSwdenkimw	- i2c memory write (fill)
2042c609719bSwdenkicrc32	- i2c checksum calculation
2043c609719bSwdenkiprobe	- probe to discover valid I2C chip addresses
2044c609719bSwdenkiloop	- infinite loop on address range
2045c609719bSwdenkisdram	- print SDRAM configuration information
2046c609719bSwdenksspi	- SPI utility commands
2047c609719bSwdenkbase	- print or set address offset
2048c609719bSwdenkprintenv- print environment variables
2049c609719bSwdenksetenv	- set environment variables
2050c609719bSwdenksaveenv - save environment variables to persistent storage
2051c609719bSwdenkprotect - enable or disable FLASH write protection
2052c609719bSwdenkerase	- erase FLASH memory
2053c609719bSwdenkflinfo	- print FLASH memory information
2054c609719bSwdenkbdinfo	- print Board Info structure
2055c609719bSwdenkiminfo	- print header information for application image
2056c609719bSwdenkconinfo - print console devices and informations
2057c609719bSwdenkide	- IDE sub-system
2058c609719bSwdenkloop	- infinite loop on address range
2059c609719bSwdenkmtest	- simple RAM test
2060c609719bSwdenkicache	- enable or disable instruction cache
2061c609719bSwdenkdcache	- enable or disable data cache
2062c609719bSwdenkreset	- Perform RESET of the CPU
2063c609719bSwdenkecho	- echo args to console
2064c609719bSwdenkversion - print monitor version
2065c609719bSwdenkhelp	- print online help
2066c609719bSwdenk?	- alias for 'help'
2067c609719bSwdenk
2068c609719bSwdenk
2069c609719bSwdenkMonitor Commands - Detailed Description:
2070c609719bSwdenk========================================
2071c609719bSwdenk
2072c609719bSwdenkTODO.
2073c609719bSwdenk
2074c609719bSwdenkFor now: just type "help <command>".
2075c609719bSwdenk
2076c609719bSwdenk
2077c609719bSwdenkEnvironment Variables:
2078c609719bSwdenk======================
2079c609719bSwdenk
2080c609719bSwdenkU-Boot supports user configuration using Environment Variables which
2081c609719bSwdenkcan be made persistent by saving to Flash memory.
2082c609719bSwdenk
2083c609719bSwdenkEnvironment Variables are set using "setenv", printed using
2084c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
2085c609719bSwdenkwithout a value can be used to delete a variable from the
2086c609719bSwdenkenvironment. As long as you don't save the environment you are
2087c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
2088c609719bSwdenkenvironment is erased by accident, a default environment is provided.
2089c609719bSwdenk
2090c609719bSwdenkSome configuration options can be set using Environment Variables:
2091c609719bSwdenk
2092c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
2093c609719bSwdenk
2094c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
2095c609719bSwdenk
2096c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
2097c609719bSwdenk
2098c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
2099c609719bSwdenk
2100c609719bSwdenk  bootfile	- Name of the image to load with TFTP
2101c609719bSwdenk
2102c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
2103c609719bSwdenk		  "bootp" will just load perform a lookup of the
2104c609719bSwdenk		  configuration from the BOOTP server, but not try to
2105c609719bSwdenk		  load any image using TFTP
2106c609719bSwdenk
2107c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
2108c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
2109c609719bSwdenk		  be automatically started (by internally calling
2110c609719bSwdenk		  "bootm")
2111c609719bSwdenk
21124a6fd34bSwdenk		  If set to "no", a standalone image passed to the
21134a6fd34bSwdenk		  "bootm" command will be copied to the load address
21144a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
21154a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
21164a6fd34bSwdenk		  data.
21174a6fd34bSwdenk
2118c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
2119c609719bSwdenk		  If this variable is not set, initrd images will be
2120c609719bSwdenk		  copied to the highest possible address in RAM; this
2121c609719bSwdenk		  is usually what you want since it allows for
2122c609719bSwdenk		  maximum initrd size. If for some reason you want to
2123c609719bSwdenk		  make sure that the initrd image is loaded below the
2124c609719bSwdenk		  CFG_BOOTMAPSZ limit, you can set this environment
2125c609719bSwdenk		  variable to a value of "no" or "off" or "0".
2126c609719bSwdenk		  Alternatively, you can set it to a maximum upper
2127c609719bSwdenk		  address to use (U-Boot will still check that it
2128c609719bSwdenk		  does not overwrite the U-Boot stack and data).
2129c609719bSwdenk
2130c609719bSwdenk		  For instance, when you have a system with 16 MB
21317152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
2132c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
2133c609719bSwdenk		  the "bootargs" variable. However, now you must make
21347152b1d0Swdenk		  sure that the initrd image is placed in the first
2135c609719bSwdenk		  12 MB as well - this can be done with
2136c609719bSwdenk
2137c609719bSwdenk		  setenv initrd_high 00c00000
2138c609719bSwdenk
213938b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
214038b99261Swdenk		  indication to U-Boot that all addresses are legal
214138b99261Swdenk		  for the Linux kernel, including addresses in flash
214238b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
214338b99261Swdenk		  ramdisk at all. This may be useful to reduce the
214438b99261Swdenk		  boot time on your system, but requires that this
214538b99261Swdenk		  feature is supported by your Linux kernel.
214638b99261Swdenk
2147c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
2148c609719bSwdenk
2149c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
2150dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
2151c609719bSwdenk
2152c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
2153c609719bSwdenk
2154c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
2155c609719bSwdenk
2156c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
2157c609719bSwdenk
2158c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
2159c609719bSwdenk
2160c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
2161c609719bSwdenk
2162c609719bSwdenk
2163c609719bSwdenkThe following environment variables may be used and automatically
2164c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
2165c609719bSwdenkdepending the information provided by your boot server:
2166c609719bSwdenk
2167c609719bSwdenk  bootfile	- see above
2168c609719bSwdenk  dnsip		- IP address of your Domain Name Server
2169fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
2170c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
2171c609719bSwdenk  hostname	- Target hostname
2172c609719bSwdenk  ipaddr	- see above
2173c609719bSwdenk  netmask	- Subnet Mask
2174c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
2175c609719bSwdenk  serverip	- see above
2176c609719bSwdenk
2177c609719bSwdenk
2178c609719bSwdenkThere are two special Environment Variables:
2179c609719bSwdenk
2180c609719bSwdenk  serial#	- contains hardware identification information such
2181c609719bSwdenk		  as type string and/or serial number
2182c609719bSwdenk  ethaddr	- Ethernet address
2183c609719bSwdenk
2184c609719bSwdenkThese variables can be set only once (usually during manufacturing of
2185c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
2186c609719bSwdenkonce they have been set once.
2187c609719bSwdenk
2188c609719bSwdenk
2189c1551ea8SstroeseFurther special Environment Variables:
2190c1551ea8Sstroese
2191c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
2192c1551ea8Sstroese		  with the "version" command. This variable is
2193c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
2194c1551ea8Sstroese
2195c1551ea8Sstroese
2196c609719bSwdenkPlease note that changes to some configuration parameters may take
2197c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
2198c609719bSwdenk
2199c609719bSwdenk
2200f07771ccSwdenkCommand Line Parsing:
2201f07771ccSwdenk=====================
2202f07771ccSwdenk
2203f07771ccSwdenkThere are two different command line parsers available with U-Boot:
22047152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
2205f07771ccSwdenk
2206f07771ccSwdenkOld, simple command line parser:
2207f07771ccSwdenk--------------------------------
2208f07771ccSwdenk
2209f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
2210f07771ccSwdenk- several commands on one line, separated by ';'
2211f07771ccSwdenk- variable substitution using "... $(name) ..." syntax
2212f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
2213f07771ccSwdenk  for example:
2214f07771ccSwdenk	setenv bootcmd bootm \$(address)
2215f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
2216f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2217f07771ccSwdenk
2218f07771ccSwdenkHush shell:
2219f07771ccSwdenk-----------
2220f07771ccSwdenk
2221f07771ccSwdenk- similar to Bourne shell, with control structures like
2222f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
2223f07771ccSwdenk  until...do...done, ...
2224f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
2225f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
2226f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
2227f07771ccSwdenk  command
2228f07771ccSwdenk
2229f07771ccSwdenkGeneral rules:
2230f07771ccSwdenk--------------
2231f07771ccSwdenk
2232f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
2233f07771ccSwdenk    command) contains several commands separated by semicolon, and
2234f07771ccSwdenk    one of these commands fails, then the remaining commands will be
2235f07771ccSwdenk    executed anyway.
2236f07771ccSwdenk
2237f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
2238f07771ccSwdenk    calling run with a list af variables as arguments), any failing
2239f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
2240f07771ccSwdenk    variables are not executed.
2241f07771ccSwdenk
2242c609719bSwdenkNote for Redundant Ethernet Interfaces:
2243c609719bSwdenk=======================================
2244c609719bSwdenk
22457152b1d0SwdenkSome boards come with redundant ethernet interfaces; U-Boot supports
2246c609719bSwdenksuch configurations and is capable of automatic selection of a
22477152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
2248c609719bSwdenk
2249c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
2250c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2251c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
2252c609719bSwdenk
2253c609719bSwdenkIf the network interface stores some valid MAC address (for instance
2254c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
2255c609719bSwdenkding setting in the environment; if the corresponding environment
2256c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
2257c609719bSwdenk
2258c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
2259c609719bSwdenk  environment, the SROM's address is used.
2260c609719bSwdenk
2261c609719bSwdenko If there is no valid address in the SROM, and a definition in the
2262c609719bSwdenk  environment exists, then the value from the environment variable is
2263c609719bSwdenk  used.
2264c609719bSwdenk
2265c609719bSwdenko If both the SROM and the environment contain a MAC address, and
2266c609719bSwdenk  both addresses are the same, this MAC address is used.
2267c609719bSwdenk
2268c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
2269c609719bSwdenk  addresses differ, the value from the environment is used and a
2270c609719bSwdenk  warning is printed.
2271c609719bSwdenk
2272c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
2273c609719bSwdenk  is raised.
2274c609719bSwdenk
2275c609719bSwdenk
2276c609719bSwdenkImage Formats:
2277c609719bSwdenk==============
2278c609719bSwdenk
2279c609719bSwdenkThe "boot" commands of this monitor operate on "image" files which
2280c609719bSwdenkcan be basicly anything, preceeded by a special header; see the
2281c609719bSwdenkdefinitions in include/image.h for details; basicly, the header
2282c609719bSwdenkdefines the following image properties:
2283c609719bSwdenk
2284c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2285c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
22867f70e853Swdenk  LynxOS, pSOS, QNX, RTEMS, ARTOS;
22871f4bb37dSwdenk  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2288c609719bSwdenk* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
22893d1e8a9dSwdenk  IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
22903d1e8a9dSwdenk  Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2291c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
2292c609719bSwdenk* Load Address
2293c609719bSwdenk* Entry Point
2294c609719bSwdenk* Image Name
2295c609719bSwdenk* Image Timestamp
2296c609719bSwdenk
2297c609719bSwdenkThe header is marked by a special Magic Number, and both the header
2298c609719bSwdenkand the data portions of the image are secured against corruption by
2299c609719bSwdenkCRC32 checksums.
2300c609719bSwdenk
2301c609719bSwdenk
2302c609719bSwdenkLinux Support:
2303c609719bSwdenk==============
2304c609719bSwdenk
2305c609719bSwdenkAlthough U-Boot should support any OS or standalone application
23067152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
2307c609719bSwdenkU-Boot.
2308c609719bSwdenk
2309c609719bSwdenkU-Boot includes many features that so far have been part of some
2310c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
2311c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
2312c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
23137152b1d0Swdenkserves several purposes:
2314c609719bSwdenk
2315c609719bSwdenk- the same features can be used for other OS or standalone
2316c609719bSwdenk  applications (for instance: using compressed images to reduce the
2317c609719bSwdenk  Flash memory footprint)
2318c609719bSwdenk
2319c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
23207152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
2321c609719bSwdenk
2322c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
2323c609719bSwdenk  images; of course this also means that different kernel images can
2324c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
2325c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
2326c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
2327c609719bSwdenk  software is easier now.
2328c609719bSwdenk
2329c609719bSwdenk
2330c609719bSwdenkLinux HOWTO:
2331c609719bSwdenk============
2332c609719bSwdenk
2333c609719bSwdenkPorting Linux to U-Boot based systems:
2334c609719bSwdenk---------------------------------------
2335c609719bSwdenk
2336c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
2337c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
2338c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
2339c609719bSwdenkLinux :-).
2340c609719bSwdenk
2341c609719bSwdenkBut now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2342c609719bSwdenk
2343c609719bSwdenkJust make sure your machine specific header file (for instance
2344c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
2345c609719bSwdenkInformation structure as we define in include/u-boot.h, and make
2346c609719bSwdenksure that your definition of IMAP_ADDR uses the same value as your
2347c609719bSwdenkU-Boot configuration in CFG_IMMR.
2348c609719bSwdenk
2349c609719bSwdenk
2350c609719bSwdenkConfiguring the Linux kernel:
2351c609719bSwdenk-----------------------------
2352c609719bSwdenk
2353c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
2354c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
2355c609719bSwdenk
2356c609719bSwdenk
2357c609719bSwdenkBuilding a Linux Image:
2358c609719bSwdenk-----------------------
2359c609719bSwdenk
236024ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
236124ee89b9Swdenknot used. If you use recent kernel source, a new build target
236224ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
236324ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
236424ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
236524ee89b9Swdenk100% compatible format.
2366c609719bSwdenk
2367c609719bSwdenkExample:
2368c609719bSwdenk
2369c609719bSwdenk	make TQM850L_config
2370c609719bSwdenk	make oldconfig
2371c609719bSwdenk	make dep
237224ee89b9Swdenk	make uImage
2373c609719bSwdenk
237424ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
237524ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
237624ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
2377c609719bSwdenk
237824ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
237924ee89b9Swdenk
238024ee89b9Swdenk* convert the kernel into a raw binary image:
238124ee89b9Swdenk
238224ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
238324ee89b9Swdenk				 -R .note -R .comment \
238424ee89b9Swdenk				 -S vmlinux linux.bin
238524ee89b9Swdenk
238624ee89b9Swdenk* compress the binary image:
238724ee89b9Swdenk
238824ee89b9Swdenk	gzip -9 linux.bin
238924ee89b9Swdenk
239024ee89b9Swdenk* package compressed binary image for U-Boot:
239124ee89b9Swdenk
239224ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
239324ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
239424ee89b9Swdenk		-d linux.bin.gz uImage
239524ee89b9Swdenk
239624ee89b9Swdenk
239724ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
239824ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
239924ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
240024ee89b9Swdenkbyte header containing information about target architecture,
240124ee89b9Swdenkoperating system, image type, compression method, entry points, time
240224ee89b9Swdenkstamp, CRC32 checksums, etc.
240324ee89b9Swdenk
240424ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
240524ee89b9Swdenkprint the header information, or to build new images.
2406c609719bSwdenk
2407c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
2408c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
2409c609719bSwdenkchecksum verification:
2410c609719bSwdenk
2411c609719bSwdenk	tools/mkimage -l image
2412c609719bSwdenk	  -l ==> list image header information
2413c609719bSwdenk
2414c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
2415c609719bSwdenkfrom a "data file" which is used as image payload:
2416c609719bSwdenk
2417c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2418c609719bSwdenk		      -n name -d data_file image
2419c609719bSwdenk	  -A ==> set architecture to 'arch'
2420c609719bSwdenk	  -O ==> set operating system to 'os'
2421c609719bSwdenk	  -T ==> set image type to 'type'
2422c609719bSwdenk	  -C ==> set compression type 'comp'
2423c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
2424c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
2425c609719bSwdenk	  -n ==> set image name to 'name'
2426c609719bSwdenk	  -d ==> use image data from 'datafile'
2427c609719bSwdenk
2428c609719bSwdenkRight now, all Linux kernels use the same load address	(0x00000000),
2429c609719bSwdenkbut the entry point address depends on the kernel version:
2430c609719bSwdenk
2431c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
243224ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
2433c609719bSwdenk
2434c609719bSwdenkSo a typical call to build a U-Boot image would read:
2435c609719bSwdenk
243624ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
243724ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
243824ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
243924ee89b9Swdenk	> examples/uImage.TQM850L
244024ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2441c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2442c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
2443c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
2444c609719bSwdenk	Load Address: 0x00000000
244524ee89b9Swdenk	Entry Point:  0x00000000
2446c609719bSwdenk
2447c609719bSwdenkTo verify the contents of the image (or check for corruption):
2448c609719bSwdenk
244924ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
245024ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2451c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2452c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
2453c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
2454c609719bSwdenk	Load Address: 0x00000000
245524ee89b9Swdenk	Entry Point:  0x00000000
2456c609719bSwdenk
2457c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
2458c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
2459c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
2460c609719bSwdenkneed to be uncompressed:
2461c609719bSwdenk
246224ee89b9Swdenk	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
246324ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
246424ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
246524ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
246624ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
246724ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2468c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2469c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
2470c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
2471c609719bSwdenk	Load Address: 0x00000000
247224ee89b9Swdenk	Entry Point:  0x00000000
2473c609719bSwdenk
2474c609719bSwdenk
2475c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
2476c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
2477c609719bSwdenk
2478c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
2479c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
2480c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2481c609719bSwdenk	Image Name:   Simple Ramdisk Image
2482c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
2483c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
2484c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
2485c609719bSwdenk	Load Address: 0x00000000
2486c609719bSwdenk	Entry Point:  0x00000000
2487c609719bSwdenk
2488c609719bSwdenk
2489c609719bSwdenkInstalling a Linux Image:
2490c609719bSwdenk-------------------------
2491c609719bSwdenk
2492c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
2493c609719bSwdenkyou must convert the image to S-Record format:
2494c609719bSwdenk
2495c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
2496c609719bSwdenk
2497c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
2498c609719bSwdenkimage header, so the resulting S-Record file will be relative to
2499c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
2500c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
2501c609719bSwdenkcommand.
2502c609719bSwdenk
2503c609719bSwdenkExample: install the image to address 0x40100000 (which on the
2504c609719bSwdenkTQM8xxL is in the first Flash bank):
2505c609719bSwdenk
2506c609719bSwdenk	=> erase 40100000 401FFFFF
2507c609719bSwdenk
2508c609719bSwdenk	.......... done
2509c609719bSwdenk	Erased 8 sectors
2510c609719bSwdenk
2511c609719bSwdenk	=> loads 40100000
2512c609719bSwdenk	## Ready for S-Record download ...
2513c609719bSwdenk	~>examples/image.srec
2514c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2515c609719bSwdenk	...
2516c609719bSwdenk	15989 15990 15991 15992
2517c609719bSwdenk	[file transfer complete]
2518c609719bSwdenk	[connected]
2519c609719bSwdenk	## Start Addr = 0x00000000
2520c609719bSwdenk
2521c609719bSwdenk
2522c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
2523c609719bSwdenkthis includes a checksum verification so you  can  be  sure  no	 data
2524c609719bSwdenkcorruption happened:
2525c609719bSwdenk
2526c609719bSwdenk	=> imi 40100000
2527c609719bSwdenk
2528c609719bSwdenk	## Checking Image at 40100000 ...
2529c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2530c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2531c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2532c609719bSwdenk	   Load Address: 00000000
2533c609719bSwdenk	   Entry Point:	 0000000c
2534c609719bSwdenk	   Verifying Checksum ... OK
2535c609719bSwdenk
2536c609719bSwdenk
2537c609719bSwdenkBoot Linux:
2538c609719bSwdenk-----------
2539c609719bSwdenk
2540c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
2541c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
2542c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
2543c609719bSwdenkparameters. You can check and modify this variable using the
2544c609719bSwdenk"printenv" and "setenv" commands:
2545c609719bSwdenk
2546c609719bSwdenk
2547c609719bSwdenk	=> printenv bootargs
2548c609719bSwdenk	bootargs=root=/dev/ram
2549c609719bSwdenk
2550c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2551c609719bSwdenk
2552c609719bSwdenk	=> printenv bootargs
2553c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2554c609719bSwdenk
2555c609719bSwdenk	=> bootm 40020000
2556c609719bSwdenk	## Booting Linux kernel at 40020000 ...
2557c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
2558c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2559c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
2560c609719bSwdenk	   Load Address: 00000000
2561c609719bSwdenk	   Entry Point:	 0000000c
2562c609719bSwdenk	   Verifying Checksum ... OK
2563c609719bSwdenk	   Uncompressing Kernel Image ... OK
2564c609719bSwdenk	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
2565c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2566c609719bSwdenk	time_init: decrementer frequency = 187500000/60
2567c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
2568c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2569c609719bSwdenk	...
2570c609719bSwdenk
2571c609719bSwdenkIf you want to boot a Linux kernel with initial ram disk, you pass
25727152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
2573c609719bSwdenkformat!) to the "bootm" command:
2574c609719bSwdenk
2575c609719bSwdenk	=> imi 40100000 40200000
2576c609719bSwdenk
2577c609719bSwdenk	## Checking Image at 40100000 ...
2578c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2579c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2580c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2581c609719bSwdenk	   Load Address: 00000000
2582c609719bSwdenk	   Entry Point:	 0000000c
2583c609719bSwdenk	   Verifying Checksum ... OK
2584c609719bSwdenk
2585c609719bSwdenk	## Checking Image at 40200000 ...
2586c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
2587c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
2588c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
2589c609719bSwdenk	   Load Address: 00000000
2590c609719bSwdenk	   Entry Point:	 00000000
2591c609719bSwdenk	   Verifying Checksum ... OK
2592c609719bSwdenk
2593c609719bSwdenk	=> bootm 40100000 40200000
2594c609719bSwdenk	## Booting Linux kernel at 40100000 ...
2595c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2596c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2597c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2598c609719bSwdenk	   Load Address: 00000000
2599c609719bSwdenk	   Entry Point:	 0000000c
2600c609719bSwdenk	   Verifying Checksum ... OK
2601c609719bSwdenk	   Uncompressing Kernel Image ... OK
2602c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
2603c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
2604c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
2605c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
2606c609719bSwdenk	   Load Address: 00000000
2607c609719bSwdenk	   Entry Point:	 00000000
2608c609719bSwdenk	   Verifying Checksum ... OK
2609c609719bSwdenk	   Loading Ramdisk ... OK
2610c609719bSwdenk	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
2611c609719bSwdenk	Boot arguments: root=/dev/ram
2612c609719bSwdenk	time_init: decrementer frequency = 187500000/60
2613c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
2614c609719bSwdenk	...
2615c609719bSwdenk	RAMDISK: Compressed image found at block 0
2616c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
2617c609719bSwdenk
2618c609719bSwdenk	bash#
2619c609719bSwdenk
26206069ff26SwdenkMore About U-Boot Image Types:
26216069ff26Swdenk------------------------------
26226069ff26Swdenk
26236069ff26SwdenkU-Boot supports the following image types:
26246069ff26Swdenk
26256069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
26266069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
26276069ff26Swdenk	well) you can continue to work in U-Boot after return from
26286069ff26Swdenk	the Standalone Program.
26296069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
26306069ff26Swdenk	will take over control completely. Usually these programs
26316069ff26Swdenk	will install their own set of exception handlers, device
26326069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
26336069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
26346069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
26356069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
26366069ff26Swdenk	being started.
26376069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
26386069ff26Swdenk	(Linux) kernel image and one or more data images like
26396069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
26406069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
26416069ff26Swdenk	server provides just a single image file, but you want to get
26426069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
26436069ff26Swdenk
26446069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
26456069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
26466069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
26476069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
26486069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
26496069ff26Swdenk	a multiple of 4 bytes).
26506069ff26Swdenk
26516069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
26526069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
26536069ff26Swdenk	flash memory.
26546069ff26Swdenk
26556069ff26Swdenk   "Script files" are command sequences that will be executed by
26566069ff26Swdenk	U-Boot's command interpreter; this feature is especially
26576069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
26586069ff26Swdenk	as command interpreter.
26596069ff26Swdenk
2660c609719bSwdenk
2661c609719bSwdenkStandalone HOWTO:
2662c609719bSwdenk=================
2663c609719bSwdenk
2664c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
2665c609719bSwdenkrun "standalone" applications, which can use some resources of
2666c609719bSwdenkU-Boot like console I/O functions or interrupt services.
2667c609719bSwdenk
2668c609719bSwdenkTwo simple examples are included with the sources:
2669c609719bSwdenk
2670c609719bSwdenk"Hello World" Demo:
2671c609719bSwdenk-------------------
2672c609719bSwdenk
2673c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
2674c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
2675c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
2676c609719bSwdenklike that:
2677c609719bSwdenk
2678c609719bSwdenk	=> loads
2679c609719bSwdenk	## Ready for S-Record download ...
2680c609719bSwdenk	~>examples/hello_world.srec
2681c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
2682c609719bSwdenk	[file transfer complete]
2683c609719bSwdenk	[connected]
2684c609719bSwdenk	## Start Addr = 0x00040004
2685c609719bSwdenk
2686c609719bSwdenk	=> go 40004 Hello World! This is a test.
2687c609719bSwdenk	## Starting application at 0x00040004 ...
2688c609719bSwdenk	Hello World
2689c609719bSwdenk	argc = 7
2690c609719bSwdenk	argv[0] = "40004"
2691c609719bSwdenk	argv[1] = "Hello"
2692c609719bSwdenk	argv[2] = "World!"
2693c609719bSwdenk	argv[3] = "This"
2694c609719bSwdenk	argv[4] = "is"
2695c609719bSwdenk	argv[5] = "a"
2696c609719bSwdenk	argv[6] = "test."
2697c609719bSwdenk	argv[7] = "<NULL>"
2698c609719bSwdenk	Hit any key to exit ...
2699c609719bSwdenk
2700c609719bSwdenk	## Application terminated, rc = 0x0
2701c609719bSwdenk
2702c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
2703c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
2704c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
2705c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
2706c609719bSwdenkcharacter, but this is just a demo program. The application can be
2707c609719bSwdenkcontrolled by the following keys:
2708c609719bSwdenk
2709c609719bSwdenk	? - print current values og the CPM Timer registers
2710c609719bSwdenk	b - enable interrupts and start timer
2711c609719bSwdenk	e - stop timer and disable interrupts
2712c609719bSwdenk	q - quit application
2713c609719bSwdenk
2714c609719bSwdenk	=> loads
2715c609719bSwdenk	## Ready for S-Record download ...
2716c609719bSwdenk	~>examples/timer.srec
2717c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
2718c609719bSwdenk	[file transfer complete]
2719c609719bSwdenk	[connected]
2720c609719bSwdenk	## Start Addr = 0x00040004
2721c609719bSwdenk
2722c609719bSwdenk	=> go 40004
2723c609719bSwdenk	## Starting application at 0x00040004 ...
2724c609719bSwdenk	TIMERS=0xfff00980
2725c609719bSwdenk	Using timer 1
2726c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2727c609719bSwdenk
2728c609719bSwdenkHit 'b':
2729c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
2730c609719bSwdenk	Enabling timer
2731c609719bSwdenkHit '?':
2732c609719bSwdenk	[q, b, e, ?] ........
2733c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2734c609719bSwdenkHit '?':
2735c609719bSwdenk	[q, b, e, ?] .
2736c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2737c609719bSwdenkHit '?':
2738c609719bSwdenk	[q, b, e, ?] .
2739c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2740c609719bSwdenkHit '?':
2741c609719bSwdenk	[q, b, e, ?] .
2742c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2743c609719bSwdenkHit 'e':
2744c609719bSwdenk	[q, b, e, ?] ...Stopping timer
2745c609719bSwdenkHit 'q':
2746c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
2747c609719bSwdenk
2748c609719bSwdenk
274985ec0bccSwdenkMinicom warning:
275085ec0bccSwdenk================
275185ec0bccSwdenk
27527152b1d0SwdenkOver time, many people have reported problems when trying to use the
275385ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
275485ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
2755f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
275685ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
275785ec0bccSwdenkuse "cu" for S-Record download ("loads" command).
275885ec0bccSwdenk
275952f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
276052f52c14Swdenkconfiguration to your "File transfer protocols" section:
276152f52c14Swdenk
276252f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
276352f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
276452f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
276552f52c14Swdenk
276652f52c14Swdenk
2767c609719bSwdenkNetBSD Notes:
2768c609719bSwdenk=============
2769c609719bSwdenk
2770c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
2771c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
2772c609719bSwdenk
2773c609719bSwdenkBuilding requires a cross environment; it is known to work on
2774c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2775c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
2776c609719bSwdenkNote that the cross-powerpc package does not install include files;
2777c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
2778c609719bSwdenkmissing.  This file has to be installed and patched manually:
2779c609719bSwdenk
2780c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
2781c609719bSwdenk	# mkdir powerpc
2782c609719bSwdenk	# ln -s powerpc machine
2783c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2784c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
2785c609719bSwdenk
2786c609719bSwdenkNative builds *don't* work due to incompatibilities between native
2787c609719bSwdenkand U-Boot include files.
2788c609719bSwdenk
2789c609719bSwdenkBooting assumes that (the first part of) the image booted is a
2790c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
2791c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
2792c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2793c609719bSwdenkmeantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2794c609719bSwdenkdetails.
2795c609719bSwdenk
2796c609719bSwdenk
2797c609719bSwdenkImplementation Internals:
2798c609719bSwdenk=========================
2799c609719bSwdenk
2800c609719bSwdenkThe following is not intended to be a complete description of every
2801c609719bSwdenkimplementation detail. However, it should help to understand the
2802c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
2803c609719bSwdenkhardware.
2804c609719bSwdenk
2805c609719bSwdenk
2806c609719bSwdenkInitial Stack, Global Data:
2807c609719bSwdenk---------------------------
2808c609719bSwdenk
2809c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
2810c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
2811c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
2812c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
2813c609719bSwdenkis not initialized as zero. To be able to get a C environment working
2814c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
2815c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
2816c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
2817c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
2818c609719bSwdenklocked as (mis-) used as memory, etc.
2819c609719bSwdenk
28207152b1d0Swdenk	Chris Hallinan posted a good summary of	 these	issues	to  the
282143d9616cSwdenk	u-boot-users mailing list:
282243d9616cSwdenk
282343d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
282443d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
282543d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
282643d9616cSwdenk	...
282743d9616cSwdenk
282843d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
282943d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
283043d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
283143d9616cSwdenk	is that the cache is being used as a temporary supply of
283243d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
283343d9616cSwdenk	beyond the scope of this list to expain the details, but you
283443d9616cSwdenk	can see how this works by studying the cache architecture and
283543d9616cSwdenk	operation in the architecture and processor-specific manuals.
283643d9616cSwdenk
283743d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
283843d9616cSwdenk	is another option for the system designer to use as an
283943d9616cSwdenk	initial stack/ram area prior to SDRAM being available. Either
284043d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
284143d9616cSwdenk	board designers haven't used it for something that would
284243d9616cSwdenk	cause you grief during the initial boot! It is frequently not
284343d9616cSwdenk	used.
284443d9616cSwdenk
284543d9616cSwdenk	CFG_INIT_RAM_ADDR should be somewhere that won't interfere
284643d9616cSwdenk	with your processor/board/system design. The default value
284743d9616cSwdenk	you will find in any recent u-boot distribution in
284843d9616cSwdenk	Walnut405.h should work for you. I'd set it to a value larger
284943d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
285043d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
285143d9616cSwdenk	that are supposed to respond to that address! That code in
285243d9616cSwdenk	start.S has been around a while and should work as is when
285343d9616cSwdenk	you get the config right.
285443d9616cSwdenk
285543d9616cSwdenk	-Chris Hallinan
285643d9616cSwdenk	DS4.COM, Inc.
285743d9616cSwdenk
2858c609719bSwdenkIt is essential to remember this, since it has some impact on the C
2859c609719bSwdenkcode for the initialization procedures:
2860c609719bSwdenk
2861c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
2862c609719bSwdenk  to write it.
2863c609719bSwdenk
2864c609719bSwdenk* Do not use any unitialized global data (or implicitely initialized
2865c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
28667152b1d0Swdenk  zation is performed later (when relocating to RAM).
2867c609719bSwdenk
2868c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
2869c609719bSwdenk  that.
2870c609719bSwdenk
2871c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
2872c609719bSwdenknormal global data to share information beween the code. But it
2873c609719bSwdenkturned out that the implementation of U-Boot can be greatly
2874c609719bSwdenksimplified by making a global data structure (gd_t) available to all
2875c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
2876c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
2877c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
2878c609719bSwdenkplace a pointer (gd) to the global data into a register which we
2879c609719bSwdenkreserve for this purpose.
2880c609719bSwdenk
28817152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
2882c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
2883c609719bSwdenkGCC's implementation.
2884c609719bSwdenk
2885c609719bSwdenkFor PowerPC, the following registers have specific use:
2886c609719bSwdenk	R1:	stack pointer
2887c609719bSwdenk	R2:	TOC pointer
2888c609719bSwdenk	R3-R4:	parameter passing and return values
2889c609719bSwdenk	R5-R10: parameter passing
2890c609719bSwdenk	R13:	small data area pointer
2891c609719bSwdenk	R30:	GOT pointer
2892c609719bSwdenk	R31:	frame pointer
2893c609719bSwdenk
2894c609719bSwdenk	(U-Boot also uses R14 as internal GOT pointer.)
2895c609719bSwdenk
2896c609719bSwdenk    ==> U-Boot will use R29 to hold a pointer to the global data
2897c609719bSwdenk
2898c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
2899c609719bSwdenk    address of the global data structure is known at compile time),
2900c609719bSwdenk    but it turned out that reserving a register results in somewhat
2901c609719bSwdenk    smaller code - although the code savings are not that big (on
2902c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
2903c609719bSwdenk    624 text + 127 data).
2904c609719bSwdenk
2905c609719bSwdenkOn ARM, the following registers are used:
2906c609719bSwdenk
2907c609719bSwdenk	R0:	function argument word/integer result
2908c609719bSwdenk	R1-R3:	function argument word
2909c609719bSwdenk	R9:	GOT pointer
2910c609719bSwdenk	R10:	stack limit (used only if stack checking if enabled)
2911c609719bSwdenk	R11:	argument (frame) pointer
2912c609719bSwdenk	R12:	temporary workspace
2913c609719bSwdenk	R13:	stack pointer
2914c609719bSwdenk	R14:	link register
2915c609719bSwdenk	R15:	program counter
2916c609719bSwdenk
2917c609719bSwdenk    ==> U-Boot will use R8 to hold a pointer to the global data
2918c609719bSwdenk
2919c609719bSwdenk
2920c609719bSwdenkMemory Management:
2921c609719bSwdenk------------------
2922c609719bSwdenk
2923c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
2924c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
2925c609719bSwdenk
2926c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
2927c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
2928c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
2929c609719bSwdenkphysical memory banks.
2930c609719bSwdenk
2931c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
2932c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2933c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
2934c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
2935c609719bSwdenkmemory is reserved for use by malloc() [see CFG_MALLOC_LEN
2936c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
2937c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
2938c609719bSwdenk
2939c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
2940c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
2941c609719bSwdenk
2942c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
2943c609719bSwdenkthis:
2944c609719bSwdenk
2945c609719bSwdenk	0x0000 0000	Exception Vector code
2946c609719bSwdenk	      :
2947c609719bSwdenk	0x0000 1FFF
2948c609719bSwdenk	0x0000 2000	Free for Application Use
2949c609719bSwdenk	      :
2950c609719bSwdenk	      :
2951c609719bSwdenk
2952c609719bSwdenk	      :
2953c609719bSwdenk	      :
2954c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
2955c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
2956c609719bSwdenk	0x00FC 0000	Malloc Arena
2957c609719bSwdenk	      :
2958c609719bSwdenk	0x00FD FFFF
2959c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
2960c609719bSwdenk	...		eventually: LCD or video framebuffer
2961c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
2962c609719bSwdenk	0x00FF FFFF	[End of RAM]
2963c609719bSwdenk
2964c609719bSwdenk
2965c609719bSwdenkSystem Initialization:
2966c609719bSwdenk----------------------
2967c609719bSwdenk
2968c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
2969c609719bSwdenk(on most PowerPC systens at address 0x00000100). Because of the reset
2970c609719bSwdenkconfiguration for CS0# this is a mirror of the onboard Flash memory.
29717152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
2972c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
2973c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
2974c609719bSwdenkwhich provide such a feature like MPC8xx or MPC8260), or in a locked
2975c609719bSwdenkpart of the data cache. After that, U-Boot initializes the CPU core,
2976c609719bSwdenkthe caches and the SIU.
2977c609719bSwdenk
2978c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
2979c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
2980c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2981c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2982c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
2983c609719bSwdenksimple memory test is run that determines the size of the SDRAM
2984c609719bSwdenkbanks.
2985c609719bSwdenk
2986c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
29877152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
2988c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
2989c609719bSwdenk0x00000000, with any additional banks following immediately to create
2990c609719bSwdenkcontiguous memory starting from 0.
2991c609719bSwdenk
2992c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
2993c609719bSwdenkand allocates memory for use by malloc() and for the global Board
2994c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
2995c609719bSwdenkpages, and the final stack is set up.
2996c609719bSwdenk
2997c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
2998c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
2999c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
3000c609719bSwdenknew address in RAM.
3001c609719bSwdenk
3002c609719bSwdenk
3003c609719bSwdenkU-Boot Porting Guide:
3004c609719bSwdenk----------------------
3005c609719bSwdenk
3006c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
30076aff3115Swdenklist, October 2002]
3008c609719bSwdenk
3009c609719bSwdenk
3010c609719bSwdenkint main (int argc, char *argv[])
3011c609719bSwdenk{
3012c609719bSwdenk	sighandler_t no_more_time;
3013c609719bSwdenk
3014c609719bSwdenk	signal (SIGALRM, no_more_time);
3015c609719bSwdenk	alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3016c609719bSwdenk
3017c609719bSwdenk	if (available_money > available_manpower) {
3018c609719bSwdenk		pay consultant to port U-Boot;
3019c609719bSwdenk		return 0;
3020c609719bSwdenk	}
3021c609719bSwdenk
3022c609719bSwdenk	Download latest U-Boot source;
3023c609719bSwdenk
30246aff3115Swdenk	Subscribe to u-boot-users mailing list;
30256aff3115Swdenk
3026c609719bSwdenk	if (clueless) {
3027c609719bSwdenk		email ("Hi, I am new to U-Boot, how do I get started?");
3028c609719bSwdenk	}
3029c609719bSwdenk
3030c609719bSwdenk	while (learning) {
3031c609719bSwdenk		Read the README file in the top level directory;
30327cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3033c609719bSwdenk		Read the source, Luke;
3034c609719bSwdenk	}
3035c609719bSwdenk
3036c609719bSwdenk	if (available_money > toLocalCurrency ($2500)) {
3037c609719bSwdenk		Buy a BDI2000;
3038c609719bSwdenk	} else {
3039c609719bSwdenk		Add a lot of aggravation and time;
3040c609719bSwdenk	}
3041c609719bSwdenk
3042c609719bSwdenk	Create your own board support subdirectory;
3043c609719bSwdenk
30446aff3115Swdenk	Create your own board config file;
30456aff3115Swdenk
3046c609719bSwdenk	while (!running) {
3047c609719bSwdenk		do {
3048c609719bSwdenk			Add / modify source code;
3049c609719bSwdenk		} until (compiles);
3050c609719bSwdenk		Debug;
3051c609719bSwdenk		if (clueless)
3052c609719bSwdenk			email ("Hi, I am having problems...");
3053c609719bSwdenk	}
3054c609719bSwdenk	Send patch file to Wolfgang;
3055c609719bSwdenk
3056c609719bSwdenk	return 0;
3057c609719bSwdenk}
3058c609719bSwdenk
3059c609719bSwdenkvoid no_more_time (int sig)
3060c609719bSwdenk{
3061c609719bSwdenk      hire_a_guru();
3062c609719bSwdenk}
3063c609719bSwdenk
3064c609719bSwdenk
3065c609719bSwdenkCoding Standards:
3066c609719bSwdenk-----------------
3067c609719bSwdenk
3068c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
3069c609719bSwdenkcoding style; see the file "Documentation/CodingStyle" in your Linux
3070c609719bSwdenkkernel source directory.
3071c609719bSwdenk
3072c609719bSwdenkPlease note that U-Boot is implemented in C (and to some small parts
3073c609719bSwdenkin Assembler); no C++ is used, so please do not use C++ style
3074c609719bSwdenkcomments (//) in your code.
3075c609719bSwdenk
3076c178d3daSwdenkPlease also stick to the following formatting rules:
3077180d3f74Swdenk- remove any trailing white space
3078180d3f74Swdenk- use TAB characters for indentation, not spaces
3079180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
3080180d3f74Swdenk- do not add more than 2 empty lines to source files
3081180d3f74Swdenk- do not add trailing empty lines to source files
3082180d3f74Swdenk
3083c609719bSwdenkSubmissions which do not conform to the standards may be returned
3084c609719bSwdenkwith a request to reformat the changes.
3085c609719bSwdenk
3086c609719bSwdenk
3087c609719bSwdenkSubmitting Patches:
3088c609719bSwdenk-------------------
3089c609719bSwdenk
3090c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
3091c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
3092c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
3093c609719bSwdenk
3094c609719bSwdenk
3095c609719bSwdenkWhen you send a patch, please include the following information with
3096c609719bSwdenkit:
3097c609719bSwdenk
3098c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
3099c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
3100c609719bSwdenk  patch actually fixes something.
3101c609719bSwdenk
3102c609719bSwdenk* For new features: a description of the feature and your
3103c609719bSwdenk  implementation.
3104c609719bSwdenk
3105c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
3106c609719bSwdenk
3107c609719bSwdenk* For major contributions, your entry to the CREDITS file
3108c609719bSwdenk
3109c609719bSwdenk* When you add support for a new board, don't forget to add this
3110c609719bSwdenk  board to the MAKEALL script, too.
3111c609719bSwdenk
3112c609719bSwdenk* If your patch adds new configuration options, don't forget to
3113c609719bSwdenk  document these in the README file.
3114c609719bSwdenk
3115c609719bSwdenk* The patch itself. If you are accessing the CVS repository use "cvs
3116c609719bSwdenk  update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3117c609719bSwdenk  version of diff does not support these options, then get the latest
3118c609719bSwdenk  version of GNU diff.
3119c609719bSwdenk
31206dff5529Swdenk  The current directory when running this command shall be the top
31216dff5529Swdenk  level directory of the U-Boot source tree, or it's parent directory
31226dff5529Swdenk  (i. e. please make sure that your patch includes sufficient
31236dff5529Swdenk  directory information for the affected files).
31246dff5529Swdenk
3125c609719bSwdenk  We accept patches as plain text, MIME attachments or as uuencoded
3126c609719bSwdenk  gzipped text.
3127c609719bSwdenk
312852f52c14Swdenk* If one logical set of modifications affects or creates several
312952f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
313052f52c14Swdenk
313152f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
313252f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
313352f52c14Swdenk
313452f52c14Swdenk
3135c609719bSwdenkNotes:
3136c609719bSwdenk
3137c609719bSwdenk* Before sending the patch, run the MAKEALL script on your patched
3138c609719bSwdenk  source tree and make sure that no errors or warnings are reported
3139c609719bSwdenk  for any of the boards.
3140c609719bSwdenk
3141c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
3142c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
3143c609719bSwdenk  returned with a request to re-formatting / split it.
3144c609719bSwdenk
3145c609719bSwdenk* If you modify existing code, make sure that your new code does not
3146c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
3147c609719bSwdenk  When adding new features, these should compile conditionally only
3148c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
3149c609719bSwdenk  disabled must not need more memory than the old code without your
3150c609719bSwdenk  modification.
3151