xref: /openbmc/u-boot/README (revision 66ca92a5ba882807ba8ed8f772c0fc22b25976cc)
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
243507bbe3eSwdenk		MicroBlaze based CPUs:
244507bbe3eSwdenk		----------------------
245857cad37Swdenk		CONFIG_MICROBLAZE
246507bbe3eSwdenk
247c609719bSwdenk
248c609719bSwdenk- Board Type:	Define exactly one of
249c609719bSwdenk
250c609719bSwdenk		PowerPC based boards:
251c609719bSwdenk		---------------------
252c609719bSwdenk
25317ea1177Swdenk		CONFIG_ADCIOP		CONFIG_GEN860T		CONFIG_PCI405
25417ea1177Swdenk		CONFIG_ADS860		CONFIG_GENIETV		CONFIG_PCIPPC2
25517ea1177Swdenk		CONFIG_AMX860		CONFIG_GTH		CONFIG_PCIPPC6
25617ea1177Swdenk		CONFIG_AR405		CONFIG_gw8260		CONFIG_pcu_e
25717ea1177Swdenk		CONFIG_BAB7xx		CONFIG_hermes		CONFIG_PIP405
25817ea1177Swdenk		CONFIG_c2mon		CONFIG_hymod		CONFIG_PM826
25917ea1177Swdenk		CONFIG_CANBT		CONFIG_IAD210		CONFIG_ppmc8260
26017ea1177Swdenk		CONFIG_CCM		CONFIG_ICU862		CONFIG_QS823
26117ea1177Swdenk		CONFIG_CMI		CONFIG_IP860		CONFIG_QS850
26217ea1177Swdenk		CONFIG_cogent_mpc8260	CONFIG_IPHASE4539	CONFIG_QS860T
26317ea1177Swdenk		CONFIG_cogent_mpc8xx	CONFIG_IVML24		CONFIG_RBC823
26417ea1177Swdenk		CONFIG_CPCI405		CONFIG_IVML24_128	CONFIG_RPXClassic
26517ea1177Swdenk		CONFIG_CPCI4052		CONFIG_IVML24_256	CONFIG_RPXlite
26617ea1177Swdenk		CONFIG_CPCIISER4	CONFIG_IVMS8		CONFIG_RPXsuper
26717ea1177Swdenk		CONFIG_CPU86		CONFIG_IVMS8_128	CONFIG_rsdproto
26817ea1177Swdenk		CONFIG_CRAYL1		CONFIG_IVMS8_256	CONFIG_sacsng
26917ea1177Swdenk		CONFIG_CSB272		CONFIG_JSE		CONFIG_Sandpoint8240
27017ea1177Swdenk		CONFIG_CU824		CONFIG_LANTEC		CONFIG_Sandpoint8245
27117ea1177Swdenk		CONFIG_DASA_SIM		CONFIG_lwmon		CONFIG_sbc8260
2728b07a110Swdenk		CONFIG_DB64360		CONFIG_MBX		CONFIG_sbc8560
2738b07a110Swdenk		CONFIG_DB64460		CONFIG_MBX860T		CONFIG_SM850
2748b07a110Swdenk		CONFIG_DU405		CONFIG_MHPC		CONFIG_SPD823TS
2758b07a110Swdenk		CONFIG_DUET_ADS		CONFIG_MIP405		CONFIG_STXGP3
2768b07a110Swdenk		CONFIG_EBONY		CONFIG_MOUSSE		CONFIG_SXNI855T
2778b07a110Swdenk		CONFIG_ELPPC		CONFIG_MPC8260ADS	CONFIG_TQM823L
2788b07a110Swdenk		CONFIG_ELPT860		CONFIG_MPC8540ADS	CONFIG_TQM8260
2798b07a110Swdenk		CONFIG_ep8260		CONFIG_MPC8560ADS	CONFIG_TQM850L
2808b07a110Swdenk		CONFIG_ERIC		CONFIG_MUSENKI		CONFIG_TQM855L
2818b07a110Swdenk		CONFIG_ESTEEM192E	CONFIG_MVS1		CONFIG_TQM860L
2828b07a110Swdenk		CONFIG_ETX094		CONFIG_NETPHONE		CONFIG_TTTech
2838b07a110Swdenk		CONFIG_EVB64260		CONFIG_NETTA		CONFIG_UTX8245
2848b07a110Swdenk		CONFIG_FADS823		CONFIG_NETVIA		CONFIG_V37
2858b07a110Swdenk		CONFIG_FADS850SAR	CONFIG_NX823		CONFIG_W7OLMC
2868b07a110Swdenk		CONFIG_FADS860T		CONFIG_OCRTC		CONFIG_W7OLMG
2878b07a110Swdenk		CONFIG_FLAGADM		CONFIG_ORSG		CONFIG_WALNUT405
2888b07a110Swdenk		CONFIG_FPS850L		CONFIG_OXC		CONFIG_ZPC1900
2898b07a110Swdenk		CONFIG_FPS860L					CONFIG_ZUMA
290c609719bSwdenk
291c609719bSwdenk		ARM based boards:
292c609719bSwdenk		-----------------
293c609719bSwdenk
294b8c83181Swdenk		CONFIG_AT91RM9200DK,		CONFIG_CERF250,		CONFIG_DNP1110,
295b8c83181Swdenk		CONFIG_EP7312,			CONFIG_H2_OMAP1610,	CONFIG_HHP_CRADLE,
296b8c83181Swdenk		CONFIG_IMPA7,		CONFIG_INNOVATOROMAP1510,	CONFIG_INNOVATOROMAP1610,
297b8c83181Swdenk		CONFIG_LART,			CONFIG_LPD7A400		CONFIG_LUBBOCK,
298b8c83181Swdenk		CONFIG_OSK_OMAP5912,		CONFIG_SHANNON,		CONFIG_P2_OMAP730,
299b8c83181Swdenk		CONFIG_SMDK2400,		CONFIG_SMDK2410,	CONFIG_TRAB,
300b8c83181Swdenk		CONFIG_VCMA9
301c609719bSwdenk
302507bbe3eSwdenk		MicroBlaze based boards:
303507bbe3eSwdenk		------------------------
304507bbe3eSwdenk
305507bbe3eSwdenk		CONFIG_SUZAKU
306507bbe3eSwdenk
307c609719bSwdenk
308c609719bSwdenk- CPU Module Type: (if CONFIG_COGENT is defined)
309c609719bSwdenk		Define exactly one of
310c609719bSwdenk		CONFIG_CMA286_60_OLD
311c609719bSwdenk--- FIXME --- not tested yet:
312c609719bSwdenk		CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
313c609719bSwdenk		CONFIG_CMA287_23, CONFIG_CMA287_50
314c609719bSwdenk
315c609719bSwdenk- Motherboard Type: (if CONFIG_COGENT is defined)
316c609719bSwdenk		Define exactly one of
317c609719bSwdenk		CONFIG_CMA101, CONFIG_CMA102
318c609719bSwdenk
319c609719bSwdenk- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
320c609719bSwdenk		Define one or more of
321c609719bSwdenk		CONFIG_CMA302
322c609719bSwdenk
323c609719bSwdenk- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
324c609719bSwdenk		Define one or more of
325c609719bSwdenk		CONFIG_LCD_HEARTBEAT	- update a character position on
326c609719bSwdenk					  the lcd display every second with
327c609719bSwdenk					  a "rotator" |\-/|\-/
328c609719bSwdenk
3292535d602Swdenk- Board flavour: (if CONFIG_MPC8260ADS is defined)
3302535d602Swdenk		CONFIG_ADSTYPE
3312535d602Swdenk		Possible values are:
3322535d602Swdenk			CFG_8260ADS	- original MPC8260ADS
333180d3f74Swdenk			CFG_8266ADS	- MPC8266ADS
33454387ac9Swdenk			CFG_PQ2FADS	- PQ2FADS-ZU or PQ2FADS-VR
33504a85b3bSwdenk			CFG_8272ADS	- MPC8272ADS
3362535d602Swdenk
337c609719bSwdenk- MPC824X Family Member (if CONFIG_MPC824X is defined)
338c609719bSwdenk		Define exactly one of
339c609719bSwdenk		CONFIG_MPC8240, CONFIG_MPC8245
340c609719bSwdenk
34175d1ea7fSwdenk- 8xx CPU Options: (if using an MPC8xx cpu)
342*66ca92a5Swdenk		CONFIG_8xx_GCLK_FREQ	- deprecated: CPU clock if
343*66ca92a5Swdenk					  get_gclk_freq() cannot work
3445da627a4Swdenk					  e.g. if there is no 32KHz
3455da627a4Swdenk					  reference PIT/RTC clock
346*66ca92a5Swdenk		CONFIG_8xx_OSCLK	- PLL input clock (either EXTCLK
347*66ca92a5Swdenk					  or XTAL/EXTAL)
348c609719bSwdenk
349*66ca92a5Swdenk- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
350*66ca92a5Swdenk		CFG_8xx_CPUCLK_MIN
351*66ca92a5Swdenk		CFG_8xx_CPUCLK_MAX
352*66ca92a5Swdenk		CONFIG_8xx_CPUCLK_DEFAULT
35375d1ea7fSwdenk			See doc/README.MPC866
35475d1ea7fSwdenk
35575d1ea7fSwdenk		CFG_MEASURE_CPUCLK
35675d1ea7fSwdenk
35775d1ea7fSwdenk		Define this to measure the actual CPU clock instead
35875d1ea7fSwdenk		of relying on the correctness of the configured
35975d1ea7fSwdenk		values. Mostly useful for board bringup to make sure
36075d1ea7fSwdenk		the PLL is locked at the intended frequency. Note
36175d1ea7fSwdenk		that this requires a (stable) reference clock (32 kHz
362*66ca92a5Swdenk		RTC clock or CFG_8XX_XIN)
36375d1ea7fSwdenk
3645da627a4Swdenk- Linux Kernel Interface:
365c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
366c609719bSwdenk
367c609719bSwdenk		U-Boot stores all clock information in Hz
368c609719bSwdenk		internally. For binary compatibility with older Linux
369c609719bSwdenk		kernels (which expect the clocks passed in the
370c609719bSwdenk		bd_info data to be in MHz) the environment variable
371c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
372c609719bSwdenk		converts clock data to MHZ before passing it to the
373c609719bSwdenk		Linux kernel.
374c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
375c609719bSwdenk		"clocks_in_mhz=1" is  automatically  included  in  the
376c609719bSwdenk		default environment.
377c609719bSwdenk
3785da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
3795da627a4Swdenk
3805da627a4Swdenk		When transfering memsize parameter to linux, some versions
3815da627a4Swdenk		expect it to be in bytes, others in MB.
3825da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
3835da627a4Swdenk
3846705d81eSwdenk- Serial Ports:
3856705d81eSwdenk		CFG_PL010_SERIAL
3866705d81eSwdenk
3876705d81eSwdenk		Define this if you want support for Amba PrimeCell PL010 UARTs.
3886705d81eSwdenk
3896705d81eSwdenk		CFG_PL011_SERIAL
3906705d81eSwdenk
3916705d81eSwdenk		Define this if you want support for Amba PrimeCell PL011 UARTs.
3926705d81eSwdenk
3936705d81eSwdenk		CONFIG_PL011_CLOCK
3946705d81eSwdenk
3956705d81eSwdenk		If you have Amba PrimeCell PL011 UARTs, set this variable to
3966705d81eSwdenk		the clock speed of the UARTs.
3976705d81eSwdenk
3986705d81eSwdenk		CONFIG_PL01x_PORTS
3996705d81eSwdenk
4006705d81eSwdenk		If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
4016705d81eSwdenk		define this to a list of base addresses for each (supported)
4026705d81eSwdenk		port. See e.g. include/configs/versatile.h
4036705d81eSwdenk
4046705d81eSwdenk
405c609719bSwdenk- Console Interface:
406c609719bSwdenk		Depending on board, define exactly one serial port
407c609719bSwdenk		(like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
408c609719bSwdenk		CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
409c609719bSwdenk		console by defining CONFIG_8xx_CONS_NONE
410c609719bSwdenk
411c609719bSwdenk		Note: if CONFIG_8xx_CONS_NONE is defined, the serial
412c609719bSwdenk		port routines must be defined elsewhere
413c609719bSwdenk		(i.e. serial_init(), serial_getc(), ...)
414c609719bSwdenk
415c609719bSwdenk		CONFIG_CFB_CONSOLE
416c609719bSwdenk		Enables console device for a color framebuffer. Needs following
417c609719bSwdenk		defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
418c609719bSwdenk			VIDEO_FB_LITTLE_ENDIAN	graphic memory organisation
419c609719bSwdenk						(default big endian)
420c609719bSwdenk			VIDEO_HW_RECTFILL	graphic chip supports
421c609719bSwdenk						rectangle fill
422c609719bSwdenk						(cf. smiLynxEM)
423c609719bSwdenk			VIDEO_HW_BITBLT		graphic chip supports
424c609719bSwdenk						bit-blit (cf. smiLynxEM)
425c609719bSwdenk			VIDEO_VISIBLE_COLS	visible pixel columns
426c609719bSwdenk						(cols=pitch)
427c609719bSwdenk			VIDEO_VISIBLE_ROWS	visible pixel rows
428c609719bSwdenk			VIDEO_PIXEL_SIZE	bytes per pixel
429c609719bSwdenk			VIDEO_DATA_FORMAT	graphic data format
430c609719bSwdenk						(0-5, cf. cfb_console.c)
431c609719bSwdenk			VIDEO_FB_ADRS		framebuffer address
432c609719bSwdenk			VIDEO_KBD_INIT_FCT	keyboard int fct
433c609719bSwdenk						(i.e. i8042_kbd_init())
434c609719bSwdenk			VIDEO_TSTC_FCT		test char fct
435c609719bSwdenk						(i.e. i8042_tstc)
436c609719bSwdenk			VIDEO_GETC_FCT		get char fct
437c609719bSwdenk						(i.e. i8042_getc)
438c609719bSwdenk			CONFIG_CONSOLE_CURSOR	cursor drawing on/off
439c609719bSwdenk						(requires blink timer
440c609719bSwdenk						cf. i8042.c)
441c609719bSwdenk			CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
442c609719bSwdenk			CONFIG_CONSOLE_TIME	display time/date info in
443c609719bSwdenk						upper right corner
444c609719bSwdenk						(requires CFG_CMD_DATE)
445c609719bSwdenk			CONFIG_VIDEO_LOGO	display Linux logo in
446c609719bSwdenk						upper left corner
447a6c7ad2fSwdenk			CONFIG_VIDEO_BMP_LOGO	use bmp_logo.h instead of
448a6c7ad2fSwdenk						linux_logo.h for logo.
449a6c7ad2fSwdenk						Requires CONFIG_VIDEO_LOGO
450c609719bSwdenk			CONFIG_CONSOLE_EXTRA_INFO
451c609719bSwdenk						addional board info beside
452c609719bSwdenk						the logo
453c609719bSwdenk
454c609719bSwdenk		When CONFIG_CFB_CONSOLE is defined, video console is
455c609719bSwdenk		default i/o. Serial console can be forced with
456c609719bSwdenk		environment 'console=serial'.
457c609719bSwdenk
458a3ad8e26Swdenk		When CONFIG_SILENT_CONSOLE is defined, all console
459a3ad8e26Swdenk		messages (by U-Boot and Linux!) can be silenced with
460a3ad8e26Swdenk		the "silent" environment variable. See
461a3ad8e26Swdenk		doc/README.silent for more information.
462a3ad8e26Swdenk
463c609719bSwdenk- Console Baudrate:
464c609719bSwdenk		CONFIG_BAUDRATE - in bps
465c609719bSwdenk		Select one of the baudrates listed in
466c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
4673bbc899fSwdenk		CFG_BRGCLK_PRESCALE, baudrate prescale
468c609719bSwdenk
469c609719bSwdenk- Interrupt driven serial port input:
470c609719bSwdenk		CONFIG_SERIAL_SOFTWARE_FIFO
471c609719bSwdenk
472c609719bSwdenk		PPC405GP only.
473c609719bSwdenk		Use an interrupt handler for receiving data on the
474c609719bSwdenk		serial port. It also enables using hardware handshake
475c609719bSwdenk		(RTS/CTS) and UART's built-in FIFO. Set the number of
476c609719bSwdenk		bytes the interrupt driven input buffer should have.
477c609719bSwdenk
478109c0e3aSwdenk		Leave undefined to disable this feature, including
479109c0e3aSwdenk		disable the buffer and hardware handshake.
480c609719bSwdenk
4811d49b1f3Sstroese- Console UART Number:
4821d49b1f3Sstroese		CONFIG_UART1_CONSOLE
4831d49b1f3Sstroese
4841d49b1f3Sstroese		IBM PPC4xx only.
4851d49b1f3Sstroese		If defined internal UART1 (and not UART0) is used
4861d49b1f3Sstroese		as default U-Boot console.
4871d49b1f3Sstroese
488c609719bSwdenk- Boot Delay:	CONFIG_BOOTDELAY - in seconds
489c609719bSwdenk		Delay before automatically booting the default image;
490c609719bSwdenk		set to -1 to disable autoboot.
491c609719bSwdenk
492c609719bSwdenk		See doc/README.autoboot for these options that
493c609719bSwdenk		work with CONFIG_BOOTDELAY. None are required.
494c609719bSwdenk		CONFIG_BOOT_RETRY_TIME
495c609719bSwdenk		CONFIG_BOOT_RETRY_MIN
496c609719bSwdenk		CONFIG_AUTOBOOT_KEYED
497c609719bSwdenk		CONFIG_AUTOBOOT_PROMPT
498c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR
499c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR
500c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR2
501c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR2
502c609719bSwdenk		CONFIG_ZERO_BOOTDELAY_CHECK
503c609719bSwdenk		CONFIG_RESET_TO_RETRY
504c609719bSwdenk
505c609719bSwdenk- Autoboot Command:
506c609719bSwdenk		CONFIG_BOOTCOMMAND
507c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
508c609719bSwdenk		define a command string that is automatically executed
509c609719bSwdenk		when no character is read on the console interface
510c609719bSwdenk		within "Boot Delay" after reset.
511c609719bSwdenk
512c609719bSwdenk		CONFIG_BOOTARGS
513c609719bSwdenk		This can be used to pass arguments to the bootm
514c609719bSwdenk		command. The value of CONFIG_BOOTARGS goes into the
515c609719bSwdenk		environment value "bootargs".
516c609719bSwdenk
517c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
518c609719bSwdenk		The value of these goes into the environment as
519c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
520c609719bSwdenk		as a convenience, when switching between booting from
521c609719bSwdenk		ram and nfs.
522c609719bSwdenk
523c609719bSwdenk- Pre-Boot Commands:
524c609719bSwdenk		CONFIG_PREBOOT
525c609719bSwdenk
526c609719bSwdenk		When this option is #defined, the existence of the
527c609719bSwdenk		environment variable "preboot" will be checked
528c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
529c609719bSwdenk		countdown and/or running the auto-boot command resp.
530c609719bSwdenk		entering interactive mode.
531c609719bSwdenk
532c609719bSwdenk		This feature is especially useful when "preboot" is
533c609719bSwdenk		automatically generated or modified. For an example
534c609719bSwdenk		see the LWMON board specific code: here "preboot" is
535c609719bSwdenk		modified when the user holds down a certain
536c609719bSwdenk		combination of keys on the (special) keyboard when
537c609719bSwdenk		booting the systems
538c609719bSwdenk
539c609719bSwdenk- Serial Download Echo Mode:
540c609719bSwdenk		CONFIG_LOADS_ECHO
541c609719bSwdenk		If defined to 1, all characters received during a
542c609719bSwdenk		serial download (using the "loads" command) are
543c609719bSwdenk		echoed back. This might be needed by some terminal
544c609719bSwdenk		emulations (like "cu"), but may as well just take
545c609719bSwdenk		time on others. This setting #define's the initial
546c609719bSwdenk		value of the "loads_echo" environment variable.
547c609719bSwdenk
548c609719bSwdenk- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
549c609719bSwdenk		CONFIG_KGDB_BAUDRATE
550c609719bSwdenk		Select one of the baudrates listed in
551c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
552c609719bSwdenk
553c609719bSwdenk- Monitor Functions:
554c609719bSwdenk		CONFIG_COMMANDS
555c609719bSwdenk		Most monitor functions can be selected (or
556c609719bSwdenk		de-selected) by adjusting the definition of
557c609719bSwdenk		CONFIG_COMMANDS; to select individual functions,
558c609719bSwdenk		#define CONFIG_COMMANDS by "OR"ing any of the
559c609719bSwdenk		following values:
560c609719bSwdenk
561c609719bSwdenk		#define enables commands:
562c609719bSwdenk		-------------------------
563c609719bSwdenk		CFG_CMD_ASKENV	* ask for env variable
56478137c3cSwdenk		CFG_CMD_AUTOSCRIPT Autoscript Support
565c609719bSwdenk		CFG_CMD_BDI	  bdinfo
5666705d81eSwdenk		CFG_CMD_BEDBUG	* Include BedBug Debugger
56778137c3cSwdenk		CFG_CMD_BMP	* BMP support
5686705d81eSwdenk		CFG_CMD_BSP	* Board specific commands
569c609719bSwdenk		CFG_CMD_BOOTD	  bootd
5706705d81eSwdenk		CFG_CMD_CACHE	* icache, dcache
571c609719bSwdenk		CFG_CMD_CONSOLE	  coninfo
572c609719bSwdenk		CFG_CMD_DATE	* support for RTC, date/time...
5736705d81eSwdenk		CFG_CMD_DHCP	* DHCP support
57478137c3cSwdenk		CFG_CMD_DIAG	* Diagnostics
57578137c3cSwdenk		CFG_CMD_DOC	* Disk-On-Chip Support
5766705d81eSwdenk		CFG_CMD_DTT	* Digital Therm and Thermostat
577c609719bSwdenk		CFG_CMD_ECHO	* echo arguments
578c609719bSwdenk		CFG_CMD_EEPROM	* EEPROM read/write support
5796705d81eSwdenk		CFG_CMD_ELF	* bootelf, bootvx
580c609719bSwdenk		CFG_CMD_ENV	  saveenv
581c609719bSwdenk		CFG_CMD_FDC	* Floppy Disk Support
5826705d81eSwdenk		CFG_CMD_FAT	* FAT partition support
5832262cfeeSwdenk		CFG_CMD_FDOS	* Dos diskette Support
584c609719bSwdenk		CFG_CMD_FLASH	  flinfo, erase, protect
585c609719bSwdenk		CFG_CMD_FPGA	  FPGA device initialization support
58678137c3cSwdenk		CFG_CMD_HWFLOW	* RTS/CTS hw flow control
587c609719bSwdenk		CFG_CMD_I2C	* I2C serial bus support
588c609719bSwdenk		CFG_CMD_IDE	* IDE harddisk support
589c609719bSwdenk		CFG_CMD_IMI	  iminfo
59078137c3cSwdenk		CFG_CMD_IMLS	  List all found images
591c609719bSwdenk		CFG_CMD_IMMAP	* IMMR dump support
592c609719bSwdenk		CFG_CMD_IRQ	* irqinfo
5936705d81eSwdenk		CFG_CMD_ITEST	  Integer/string test of 2 values
59478137c3cSwdenk		CFG_CMD_JFFS2	* JFFS2 Support
595c609719bSwdenk		CFG_CMD_KGDB	* kgdb
596c609719bSwdenk		CFG_CMD_LOADB	  loadb
597c609719bSwdenk		CFG_CMD_LOADS	  loads
598c609719bSwdenk		CFG_CMD_MEMORY	  md, mm, nm, mw, cp, cmp, crc, base,
59956523f12Swdenk				  loop, loopw, mtest
60078137c3cSwdenk		CFG_CMD_MISC	  Misc functions like sleep etc
6016705d81eSwdenk		CFG_CMD_MMC	* MMC memory mapped support
6026705d81eSwdenk		CFG_CMD_MII	* MII utility commands
60378137c3cSwdenk		CFG_CMD_NAND	* NAND support
604c609719bSwdenk		CFG_CMD_NET	  bootp, tftpboot, rarpboot
605c609719bSwdenk		CFG_CMD_PCI	* pciinfo
606c609719bSwdenk		CFG_CMD_PCMCIA	* PCMCIA support
60778137c3cSwdenk		CFG_CMD_PING	* send ICMP ECHO_REQUEST to network host
608ef5a9672Swdenk		CFG_CMD_PORTIO	* Port I/O
609c609719bSwdenk		CFG_CMD_REGINFO * Register dump
610c609719bSwdenk		CFG_CMD_RUN	  run command in env variable
6116705d81eSwdenk		CFG_CMD_SAVES	* save S record dump
612c609719bSwdenk		CFG_CMD_SCSI	* SCSI Support
61378137c3cSwdenk		CFG_CMD_SDRAM	* print SDRAM configuration information
614c609719bSwdenk		CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
615c609719bSwdenk		CFG_CMD_SPI	* SPI serial bus support
616c609719bSwdenk		CFG_CMD_USB	* USB support
61778137c3cSwdenk		CFG_CMD_VFD	* VFD support (TRAB)
618c609719bSwdenk		CFG_CMD_BSP	* Board SPecific functions
619a3d991bdSwdenk		CFG_CMD_CDP	* Cisco Discover Protocol support
620c609719bSwdenk		-----------------------------------------------
621c609719bSwdenk		CFG_CMD_ALL	all
622c609719bSwdenk
62381050926Swdenk		CONFIG_CMD_DFL	Default configuration; at the moment
624c609719bSwdenk				this is includes all commands, except
625c609719bSwdenk				the ones marked with "*" in the list
626c609719bSwdenk				above.
627c609719bSwdenk
628c609719bSwdenk		If you don't define CONFIG_COMMANDS it defaults to
62981050926Swdenk		CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
630c609719bSwdenk		override the default settings in the respective
631c609719bSwdenk		include file.
632c609719bSwdenk
633c609719bSwdenk		EXAMPLE: If you want all functions except of network
634c609719bSwdenk		support you can write:
635c609719bSwdenk
636c609719bSwdenk		#define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
637c609719bSwdenk
638c609719bSwdenk
639c609719bSwdenk	Note:	Don't enable the "icache" and "dcache" commands
640c609719bSwdenk		(configuration option CFG_CMD_CACHE) unless you know
641c609719bSwdenk		what you (and your U-Boot users) are doing. Data
642c609719bSwdenk		cache cannot be enabled on systems like the 8xx or
643c609719bSwdenk		8260 (where accesses to the IMMR region must be
644c609719bSwdenk		uncached), and it cannot be disabled on all other
645c609719bSwdenk		systems where we (mis-) use the data cache to hold an
646c609719bSwdenk		initial stack and some data.
647c609719bSwdenk
648c609719bSwdenk
649c609719bSwdenk		XXX - this list needs to get updated!
650c609719bSwdenk
651c609719bSwdenk- Watchdog:
652c609719bSwdenk		CONFIG_WATCHDOG
653c609719bSwdenk		If this variable is defined, it enables watchdog
6547152b1d0Swdenk		support. There must be support in the platform specific
655c609719bSwdenk		code for a watchdog. For the 8xx and 8260 CPUs, the
656c609719bSwdenk		SIU Watchdog feature is enabled in the SYPCR
657c609719bSwdenk		register.
658c609719bSwdenk
659c1551ea8Sstroese- U-Boot Version:
660c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
661c1551ea8Sstroese		If this variable is defined, an environment variable
662c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
663c1551ea8Sstroese		version as printed by the "version" command.
664c1551ea8Sstroese		This variable is readonly.
665c1551ea8Sstroese
666c609719bSwdenk- Real-Time Clock:
667c609719bSwdenk
668c609719bSwdenk		When CFG_CMD_DATE is selected, the type of the RTC
669c609719bSwdenk		has to be selected, too. Define exactly one of the
670c609719bSwdenk		following options:
671c609719bSwdenk
672c609719bSwdenk		CONFIG_RTC_MPC8xx	- use internal RTC of MPC8xx
673c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
674c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
6751cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
676c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
6777f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
6783bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
6794c0d4c3bSwdenk		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
680c609719bSwdenk
681b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
682b37c7e5eSwdenk		must also be configured. See I2C Support, below.
683b37c7e5eSwdenk
684c609719bSwdenk- Timestamp Support:
685c609719bSwdenk
686c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
687c609719bSwdenk		(date and time) of an image is printed by image
688c609719bSwdenk		commands like bootm or iminfo. This option is
689c609719bSwdenk		automatically enabled when you select CFG_CMD_DATE .
690c609719bSwdenk
691c609719bSwdenk- Partition Support:
692c609719bSwdenk		CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
693c609719bSwdenk		and/or CONFIG_ISO_PARTITION
694c609719bSwdenk
695c609719bSwdenk		If IDE or SCSI support	is  enabled  (CFG_CMD_IDE  or
696c609719bSwdenk		CFG_CMD_SCSI) you must configure support for at least
697c609719bSwdenk		one partition type as well.
698c609719bSwdenk
699c609719bSwdenk- IDE Reset method:
7004d13cbadSwdenk		CONFIG_IDE_RESET_ROUTINE - this is defined in several
7014d13cbadSwdenk		board configurations files but used nowhere!
702c609719bSwdenk
7034d13cbadSwdenk		CONFIG_IDE_RESET - is this is defined, IDE Reset will
7044d13cbadSwdenk		be performed by calling the function
7054d13cbadSwdenk			ide_set_reset(int reset)
7064d13cbadSwdenk		which has to be defined in a board specific file
707c609719bSwdenk
708c609719bSwdenk- ATAPI Support:
709c609719bSwdenk		CONFIG_ATAPI
710c609719bSwdenk
711c609719bSwdenk		Set this to enable ATAPI support.
712c609719bSwdenk
713c40b2956Swdenk- LBA48 Support
714c40b2956Swdenk		CONFIG_LBA48
715c40b2956Swdenk
716c40b2956Swdenk		Set this to enable support for disks larger than 137GB
717c40b2956Swdenk		Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
718c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
719c40b2956Swdenk		support disks up to 2.1TB.
720c40b2956Swdenk
721c40b2956Swdenk		CFG_64BIT_LBA:
722c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
723c40b2956Swdenk			Default is 32bit.
724c40b2956Swdenk
725c609719bSwdenk- SCSI Support:
726c609719bSwdenk		At the moment only there is only support for the
727c609719bSwdenk		SYM53C8XX SCSI controller; define
728c609719bSwdenk		CONFIG_SCSI_SYM53C8XX to enable it.
729c609719bSwdenk
730c609719bSwdenk		CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
731c609719bSwdenk		CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
732c609719bSwdenk		CFG_SCSI_MAX_LUN] can be adjusted to define the
733c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
734c609719bSwdenk		devices.
735c609719bSwdenk		CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
736c609719bSwdenk
737c609719bSwdenk- NETWORK Support (PCI):
738682011ffSwdenk		CONFIG_E1000
739682011ffSwdenk		Support for Intel 8254x gigabit chips.
740682011ffSwdenk
741c609719bSwdenk		CONFIG_EEPRO100
742c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
743c609719bSwdenk		Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
744c609719bSwdenk		write routine for first time initialisation.
745c609719bSwdenk
746c609719bSwdenk		CONFIG_TULIP
747c609719bSwdenk		Support for Digital 2114x chips.
748c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
749c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
750c609719bSwdenk
751c609719bSwdenk		CONFIG_NATSEMI
752c609719bSwdenk		Support for National dp83815 chips.
753c609719bSwdenk
754c609719bSwdenk		CONFIG_NS8382X
755c609719bSwdenk		Support for National dp8382[01] gigabit chips.
756c609719bSwdenk
75745219c46Swdenk- NETWORK Support (other):
75845219c46Swdenk
75945219c46Swdenk		CONFIG_DRIVER_LAN91C96
76045219c46Swdenk		Support for SMSC's LAN91C96 chips.
76145219c46Swdenk
76245219c46Swdenk			CONFIG_LAN91C96_BASE
76345219c46Swdenk			Define this to hold the physical address
76445219c46Swdenk			of the LAN91C96's I/O space
76545219c46Swdenk
76645219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
76745219c46Swdenk			Define this to enable 32 bit addressing
76845219c46Swdenk
769f39748aeSwdenk		CONFIG_DRIVER_SMC91111
770f39748aeSwdenk		Support for SMSC's LAN91C111 chip
771f39748aeSwdenk
772f39748aeSwdenk			CONFIG_SMC91111_BASE
773f39748aeSwdenk			Define this to hold the physical address
774f39748aeSwdenk			of the device (I/O space)
775f39748aeSwdenk
776f39748aeSwdenk			CONFIG_SMC_USE_32_BIT
777f39748aeSwdenk			Define this if data bus is 32 bits
778f39748aeSwdenk
779f39748aeSwdenk			CONFIG_SMC_USE_IOFUNCS
780f39748aeSwdenk			Define this to use i/o functions instead of macros
781f39748aeSwdenk			(some hardware wont work with macros)
782f39748aeSwdenk
783c609719bSwdenk- USB Support:
784c609719bSwdenk		At the moment only the UHCI host controller is
7854d13cbadSwdenk		supported (PIP405, MIP405, MPC5200); define
786c609719bSwdenk		CONFIG_USB_UHCI to enable it.
787c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
788c609719bSwdenk		end define CONFIG_USB_STORAGE to enable the USB
789c609719bSwdenk		storage devices.
790c609719bSwdenk		Note:
791c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
792c609719bSwdenk		(TEAC FD-05PUB).
7934d13cbadSwdenk		MPC5200 USB requires additional defines:
7944d13cbadSwdenk			CONFIG_USB_CLOCK
7954d13cbadSwdenk				for 528 MHz Clock: 0x0001bbbb
7964d13cbadSwdenk			CONFIG_USB_CONFIG
7974d13cbadSwdenk				for differential drivers: 0x00001000
7984d13cbadSwdenk				for single ended drivers: 0x00005000
7994d13cbadSwdenk
800c609719bSwdenk
80171f95118Swdenk- MMC Support:
80271f95118Swdenk		The MMC controller on the Intel PXA is supported. To
80371f95118Swdenk		enable this define CONFIG_MMC. The MMC can be
80471f95118Swdenk		accessed from the boot prompt by mapping the device
80571f95118Swdenk		to physical memory similar to flash. Command line is
80671f95118Swdenk		enabled with CFG_CMD_MMC. The MMC driver also works with
80771f95118Swdenk		the FAT fs. This is enabled with CFG_CMD_FAT.
80871f95118Swdenk
8096705d81eSwdenk- Journaling Flash filesystem support:
8106705d81eSwdenk		CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
8116705d81eSwdenk		CONFIG_JFFS2_NAND_DEV
8126705d81eSwdenk		Define these for a default partition on a NAND device
8136705d81eSwdenk
8146705d81eSwdenk		CFG_JFFS2_FIRST_SECTOR,
8156705d81eSwdenk		CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
8166705d81eSwdenk		Define these for a default partition on a NOR device
8176705d81eSwdenk
8186705d81eSwdenk		CFG_JFFS_CUSTOM_PART
8196705d81eSwdenk		Define this to create an own partition. You have to provide a
8206705d81eSwdenk		function struct part_info* jffs2_part_info(int part_num)
8216705d81eSwdenk
8226705d81eSwdenk		If you define only one JFFS2 partition you may also want to
8236705d81eSwdenk		#define CFG_JFFS_SINGLE_PART    1
8246705d81eSwdenk		to disable the command chpart. This is the default when you
8256705d81eSwdenk		have not defined a custom partition
8266705d81eSwdenk
827c609719bSwdenk- Keyboard Support:
828c609719bSwdenk		CONFIG_ISA_KEYBOARD
829c609719bSwdenk
830c609719bSwdenk		Define this to enable standard (PC-Style) keyboard
831c609719bSwdenk		support
832c609719bSwdenk
833c609719bSwdenk		CONFIG_I8042_KBD
834c609719bSwdenk		Standard PC keyboard driver with US (is default) and
835c609719bSwdenk		GERMAN key layout (switch via environment 'keymap=de') support.
836c609719bSwdenk		Export function i8042_kbd_init, i8042_tstc and i8042_getc
837c609719bSwdenk		for cfb_console. Supports cursor blinking.
838c609719bSwdenk
839c609719bSwdenk- Video support:
840c609719bSwdenk		CONFIG_VIDEO
841c609719bSwdenk
842c609719bSwdenk		Define this to enable video support (for output to
843c609719bSwdenk		video).
844c609719bSwdenk
845c609719bSwdenk		CONFIG_VIDEO_CT69000
846c609719bSwdenk
847c609719bSwdenk		Enable Chips & Technologies 69000 Video chip
848c609719bSwdenk
849c609719bSwdenk		CONFIG_VIDEO_SMI_LYNXEM
850eeb1b77bSwdenk		Enable Silicon Motion SMI 712/710/810 Video chip. The
851eeb1b77bSwdenk		video output is selected via environment 'videoout'
852eeb1b77bSwdenk		(1 = LCD and 2 = CRT). If videoout is undefined, CRT is
853eeb1b77bSwdenk		assumed.
854c609719bSwdenk
855eeb1b77bSwdenk		For the CT69000 and SMI_LYNXEM drivers, videomode is
856eeb1b77bSwdenk		selected via environment 'videomode'. Two diferent ways
857eeb1b77bSwdenk		are possible:
858eeb1b77bSwdenk		- "videomode=num"   'num' is a standard LiLo mode numbers.
859eeb1b77bSwdenk		Following standard modes are supported	(* is default):
860eeb1b77bSwdenk
861eeb1b77bSwdenk		      Colors	640x480 800x600 1024x768 1152x864 1280x1024
862eeb1b77bSwdenk		-------------+---------------------------------------------
863eeb1b77bSwdenk		      8 bits |	0x301*	0x303	 0x305	  0x161	    0x307
864eeb1b77bSwdenk		     15 bits |	0x310	0x313	 0x316	  0x162	    0x319
865eeb1b77bSwdenk		     16 bits |	0x311	0x314	 0x317	  0x163	    0x31A
866eeb1b77bSwdenk		     24 bits |	0x312	0x315	 0x318	    ?	    0x31B
867eeb1b77bSwdenk		-------------+---------------------------------------------
868c609719bSwdenk		(i.e. setenv videomode 317; saveenv; reset;)
869c609719bSwdenk
870eeb1b77bSwdenk		- "videomode=bootargs" all the video parameters are parsed
871eeb1b77bSwdenk		from the bootargs. (See drivers/videomodes.c)
872eeb1b77bSwdenk
873eeb1b77bSwdenk
874a6c7ad2fSwdenk		CONFIG_VIDEO_SED13806
875a6c7ad2fSwdenk		Enable Epson SED13806 driver. This driver supports 8bpp
876a6c7ad2fSwdenk		and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
877a6c7ad2fSwdenk		or CONFIG_VIDEO_SED13806_16BPP
878a6c7ad2fSwdenk
879682011ffSwdenk- Keyboard Support:
880682011ffSwdenk		CONFIG_KEYBOARD
881682011ffSwdenk
882682011ffSwdenk		Define this to enable a custom keyboard support.
883682011ffSwdenk		This simply calls drv_keyboard_init() which must be
884682011ffSwdenk		defined in your board-specific files.
885682011ffSwdenk		The only board using this so far is RBC823.
886a6c7ad2fSwdenk
887c609719bSwdenk- LCD Support:	CONFIG_LCD
888c609719bSwdenk
889c609719bSwdenk		Define this to enable LCD support (for output to LCD
890c609719bSwdenk		display); also select one of the supported displays
891c609719bSwdenk		by defining one of these:
892c609719bSwdenk
893fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
894c609719bSwdenk
895fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
896c609719bSwdenk
897fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
898c609719bSwdenk
899fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
900fd3103bbSwdenk			Active, color, single scan.
901fd3103bbSwdenk
902fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
903fd3103bbSwdenk
904fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
905c609719bSwdenk			Active, color, single scan.
906c609719bSwdenk
907c609719bSwdenk		CONFIG_SHARP_16x9
908c609719bSwdenk
909c609719bSwdenk			Sharp 320x240. Active, color, single scan.
910c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
911c609719bSwdenk
912c609719bSwdenk		CONFIG_SHARP_LQ64D341
913c609719bSwdenk
914c609719bSwdenk			Sharp LQ64D341 display, 640x480.
915c609719bSwdenk			Active, color, single scan.
916c609719bSwdenk
917c609719bSwdenk		CONFIG_HLD1045
918c609719bSwdenk
919c609719bSwdenk			HLD1045 display, 640x480.
920c609719bSwdenk			Active, color, single scan.
921c609719bSwdenk
922c609719bSwdenk		CONFIG_OPTREX_BW
923c609719bSwdenk
924c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
925c609719bSwdenk			or
926c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
927c609719bSwdenk			or
928c609719bSwdenk			Hitachi	 SP14Q002
929c609719bSwdenk
930c609719bSwdenk			320x240. Black & white.
931c609719bSwdenk
932c609719bSwdenk		Normally display is black on white background; define
933c609719bSwdenk		CFG_WHITE_ON_BLACK to get it inverted.
934c609719bSwdenk
9357152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
936d791b1dcSwdenk
937d791b1dcSwdenk		If this option is set, the environment is checked for
938d791b1dcSwdenk		a variable "splashimage". If found, the usual display
939d791b1dcSwdenk		of logo, copyright and system information on the LCD
940e94d2cd9Swdenk		is suppressed and the BMP image at the address
941d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
942d791b1dcSwdenk		console is redirected to the "nulldev", too. This
943d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
944d791b1dcSwdenk		loaded very quickly after power-on.
945d791b1dcSwdenk
946c29fdfc1Swdenk- Compression support:
947c29fdfc1Swdenk		CONFIG_BZIP2
948c29fdfc1Swdenk
949c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
950c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
951c29fdfc1Swdenk		compressed images are supported.
952c29fdfc1Swdenk
953c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
954c29fdfc1Swdenk		the malloc area (as defined by CFG_MALLOC_LEN) should
955c29fdfc1Swdenk		be at least 4MB.
956d791b1dcSwdenk
95717ea1177Swdenk- MII/PHY support:
95817ea1177Swdenk		CONFIG_PHY_ADDR
95917ea1177Swdenk
96017ea1177Swdenk		The address of PHY on MII bus.
96117ea1177Swdenk
96217ea1177Swdenk		CONFIG_PHY_CLOCK_FREQ (ppc4xx)
96317ea1177Swdenk
96417ea1177Swdenk		The clock frequency of the MII bus
96517ea1177Swdenk
96617ea1177Swdenk		CONFIG_PHY_GIGE
96717ea1177Swdenk
96817ea1177Swdenk		If this option is set, support for speed/duplex
96917ea1177Swdenk		detection of Gigabit PHY is included.
97017ea1177Swdenk
97117ea1177Swdenk		CONFIG_PHY_RESET_DELAY
97217ea1177Swdenk
97317ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
97417ea1177Swdenk		reset before any MII register access is possible.
97517ea1177Swdenk		For such PHY, set this option to the usec delay
97617ea1177Swdenk		required. (minimum 300usec for LXT971A)
97717ea1177Swdenk
97817ea1177Swdenk		CONFIG_PHY_CMD_DELAY (ppc4xx)
97917ea1177Swdenk
98017ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
98117ea1177Swdenk		command issued before MII status register can be read
98217ea1177Swdenk
983c609719bSwdenk- Ethernet address:
984c609719bSwdenk		CONFIG_ETHADDR
985c609719bSwdenk		CONFIG_ETH2ADDR
986c609719bSwdenk		CONFIG_ETH3ADDR
987c609719bSwdenk
988c609719bSwdenk		Define a default value for ethernet address to use
989c609719bSwdenk		for the respective ethernet interface, in case this
990c609719bSwdenk		is not determined automatically.
991c609719bSwdenk
992c609719bSwdenk- IP address:
993c609719bSwdenk		CONFIG_IPADDR
994c609719bSwdenk
995c609719bSwdenk		Define a default value for the IP address to use for
996c609719bSwdenk		the default ethernet interface, in case this is not
997c609719bSwdenk		determined through e.g. bootp.
998c609719bSwdenk
999c609719bSwdenk- Server IP address:
1000c609719bSwdenk		CONFIG_SERVERIP
1001c609719bSwdenk
1002c609719bSwdenk		Defines a default value for theIP address of a TFTP
1003c609719bSwdenk		server to contact when using the "tftboot" command.
1004c609719bSwdenk
1005c609719bSwdenk- BOOTP Recovery Mode:
1006c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
1007c609719bSwdenk
1008c609719bSwdenk		If you have many targets in a network that try to
1009c609719bSwdenk		boot using BOOTP, you may want to avoid that all
1010c609719bSwdenk		systems send out BOOTP requests at precisely the same
1011c609719bSwdenk		moment (which would happen for instance at recovery
1012c609719bSwdenk		from a power failure, when all systems will try to
1013c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
1014c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1015c609719bSwdenk		inserted before sending out BOOTP requests. The
1016c609719bSwdenk		following delays are insterted then:
1017c609719bSwdenk
1018c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
1019c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
1020c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
1021c609719bSwdenk		4th and following
1022c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
1023c609719bSwdenk
1024fe389a82Sstroese- DHCP Advanced Options:
1025fe389a82Sstroese		CONFIG_BOOTP_MASK
1026fe389a82Sstroese
1027fe389a82Sstroese		You can fine tune the DHCP functionality by adding
1028fe389a82Sstroese		these flags to the CONFIG_BOOTP_MASK define:
1029fe389a82Sstroese
1030fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1031fe389a82Sstroese		serverip from a DHCP server, it is possible that more
1032fe389a82Sstroese		than one DNS serverip is offered to the client.
1033fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1034fe389a82Sstroese		serverip will be stored in the additional environment
1035fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
1036fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1037fe389a82Sstroese		is added to the CONFIG_BOOTP_MASK.
1038fe389a82Sstroese
1039fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1040fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
1041fe389a82Sstroese		need the hostname of the DHCP requester.
1042fe389a82Sstroese		If CONFIG_BOOP_SEND_HOSTNAME is added to the
1043fe389a82Sstroese		CONFIG_BOOTP_MASK, the content of the "hostname"
1044fe389a82Sstroese		environment variable is passed as option 12 to
1045fe389a82Sstroese		the DHCP server.
1046fe389a82Sstroese
1047a3d991bdSwdenk - CDP Options:
1048a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID
1049a3d991bdSwdenk
1050a3d991bdSwdenk		The device id used in CDP trigger frames.
1051a3d991bdSwdenk
1052a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID_PREFIX
1053a3d991bdSwdenk
1054a3d991bdSwdenk		A two character string which is prefixed to the MAC address
1055a3d991bdSwdenk		of the device.
1056a3d991bdSwdenk
1057a3d991bdSwdenk		CONFIG_CDP_PORT_ID
1058a3d991bdSwdenk
1059a3d991bdSwdenk		A printf format string which contains the ascii name of
1060a3d991bdSwdenk		the port. Normally is set to "eth%d" which sets
1061a3d991bdSwdenk		eth0 for the first ethernet, eth1 for the second etc.
1062a3d991bdSwdenk
1063a3d991bdSwdenk		CONFIG_CDP_CAPABILITIES
1064a3d991bdSwdenk
1065a3d991bdSwdenk		A 32bit integer which indicates the device capabilities;
1066a3d991bdSwdenk		0x00000010 for a normal host which does not forwards.
1067a3d991bdSwdenk
1068a3d991bdSwdenk		CONFIG_CDP_VERSION
1069a3d991bdSwdenk
1070a3d991bdSwdenk		An ascii string containing the version of the software.
1071a3d991bdSwdenk
1072a3d991bdSwdenk		CONFIG_CDP_PLATFORM
1073a3d991bdSwdenk
1074a3d991bdSwdenk		An ascii string containing the name of the platform.
1075a3d991bdSwdenk
1076a3d991bdSwdenk		CONFIG_CDP_TRIGGER
1077a3d991bdSwdenk
1078a3d991bdSwdenk		A 32bit integer sent on the trigger.
1079a3d991bdSwdenk
1080a3d991bdSwdenk		CONFIG_CDP_POWER_CONSUMPTION
1081a3d991bdSwdenk
1082a3d991bdSwdenk		A 16bit integer containing the power consumption of the
1083a3d991bdSwdenk		device in .1 of milliwatts.
1084a3d991bdSwdenk
1085a3d991bdSwdenk		CONFIG_CDP_APPLIANCE_VLAN_TYPE
1086a3d991bdSwdenk
1087a3d991bdSwdenk		A byte containing the id of the VLAN.
1088a3d991bdSwdenk
1089c609719bSwdenk- Status LED:	CONFIG_STATUS_LED
1090c609719bSwdenk
1091c609719bSwdenk		Several configurations allow to display the current
1092c609719bSwdenk		status using a LED. For instance, the LED will blink
1093c609719bSwdenk		fast while running U-Boot code, stop blinking as
1094c609719bSwdenk		soon as a reply to a BOOTP request was received, and
1095c609719bSwdenk		start blinking slow once the Linux kernel is running
1096c609719bSwdenk		(supported by a status LED driver in the Linux
1097c609719bSwdenk		kernel). Defining CONFIG_STATUS_LED enables this
1098c609719bSwdenk		feature in U-Boot.
1099c609719bSwdenk
1100c609719bSwdenk- CAN Support:	CONFIG_CAN_DRIVER
1101c609719bSwdenk
1102c609719bSwdenk		Defining CONFIG_CAN_DRIVER enables CAN driver support
1103c609719bSwdenk		on those systems that support this (optional)
1104c609719bSwdenk		feature, like the TQM8xxL modules.
1105c609719bSwdenk
1106c609719bSwdenk- I2C Support:	CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1107c609719bSwdenk
1108b37c7e5eSwdenk		These enable I2C serial bus commands. Defining either of
1109b37c7e5eSwdenk		(but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1110b37c7e5eSwdenk		include the appropriate I2C driver for the selected cpu.
1111c609719bSwdenk
1112b37c7e5eSwdenk		This will allow you to use i2c commands at the u-boot
1113b37c7e5eSwdenk		command line (as long as you set CFG_CMD_I2C in
1114b37c7e5eSwdenk		CONFIG_COMMANDS) and communicate with i2c based realtime
1115b37c7e5eSwdenk		clock chips. See common/cmd_i2c.c for a description of the
1116c609719bSwdenk		command line interface.
1117c609719bSwdenk
1118b37c7e5eSwdenk		CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1119c609719bSwdenk
1120b37c7e5eSwdenk		CONFIG_SOFT_I2C configures u-boot to use a software (aka
1121b37c7e5eSwdenk		bit-banging) driver instead of CPM or similar hardware
1122b37c7e5eSwdenk		support for I2C.
1123c609719bSwdenk
1124b37c7e5eSwdenk		There are several other quantities that must also be
1125b37c7e5eSwdenk		defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1126c609719bSwdenk
1127b37c7e5eSwdenk		In both cases you will need to define CFG_I2C_SPEED
1128b37c7e5eSwdenk		to be the frequency (in Hz) at which you wish your i2c bus
1129b37c7e5eSwdenk		to run and CFG_I2C_SLAVE to be the address of this node (ie
1130b37c7e5eSwdenk		the cpu's i2c node address).
1131c609719bSwdenk
1132b37c7e5eSwdenk		Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1133b37c7e5eSwdenk		sets the cpu up as a master node and so its address should
1134b37c7e5eSwdenk		therefore be cleared to 0 (See, eg, MPC823e User's Manual
1135b37c7e5eSwdenk		p.16-473). So, set CFG_I2C_SLAVE to 0.
1136b37c7e5eSwdenk
1137b37c7e5eSwdenk		That's all that's required for CONFIG_HARD_I2C.
1138b37c7e5eSwdenk
1139b37c7e5eSwdenk		If you use the software i2c interface (CONFIG_SOFT_I2C)
1140b37c7e5eSwdenk		then the following macros need to be defined (examples are
1141b37c7e5eSwdenk		from include/configs/lwmon.h):
1142c609719bSwdenk
1143c609719bSwdenk		I2C_INIT
1144c609719bSwdenk
1145b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
1146c609719bSwdenk		controller or configure ports.
1147c609719bSwdenk
1148b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
1149b37c7e5eSwdenk
1150c609719bSwdenk		I2C_PORT
1151c609719bSwdenk
1152c609719bSwdenk		(Only for MPC8260 CPU). The I/O port to use (the code
1153c609719bSwdenk		assumes both bits are on the same port). Valid values
1154c609719bSwdenk		are 0..3 for ports A..D.
1155c609719bSwdenk
1156c609719bSwdenk		I2C_ACTIVE
1157c609719bSwdenk
1158c609719bSwdenk		The code necessary to make the I2C data line active
1159c609719bSwdenk		(driven).  If the data line is open collector, this
1160c609719bSwdenk		define can be null.
1161c609719bSwdenk
1162b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
1163b37c7e5eSwdenk
1164c609719bSwdenk		I2C_TRISTATE
1165c609719bSwdenk
1166c609719bSwdenk		The code necessary to make the I2C data line tri-stated
1167c609719bSwdenk		(inactive).  If the data line is open collector, this
1168c609719bSwdenk		define can be null.
1169c609719bSwdenk
1170b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1171b37c7e5eSwdenk
1172c609719bSwdenk		I2C_READ
1173c609719bSwdenk
1174c609719bSwdenk		Code that returns TRUE if the I2C data line is high,
1175c609719bSwdenk		FALSE if it is low.
1176c609719bSwdenk
1177b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1178b37c7e5eSwdenk
1179c609719bSwdenk		I2C_SDA(bit)
1180c609719bSwdenk
1181c609719bSwdenk		If <bit> is TRUE, sets the I2C data line high. If it
1182c609719bSwdenk		is FALSE, it clears it (low).
1183c609719bSwdenk
1184b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
1185b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
1186b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
1187b37c7e5eSwdenk
1188c609719bSwdenk		I2C_SCL(bit)
1189c609719bSwdenk
1190c609719bSwdenk		If <bit> is TRUE, sets the I2C clock line high. If it
1191c609719bSwdenk		is FALSE, it clears it (low).
1192c609719bSwdenk
1193b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
1194b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
1195b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
1196b37c7e5eSwdenk
1197c609719bSwdenk		I2C_DELAY
1198c609719bSwdenk
1199c609719bSwdenk		This delay is invoked four times per clock cycle so this
1200c609719bSwdenk		controls the rate of data transfer.  The data rate thus
1201b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
1202b37c7e5eSwdenk		like:
1203b37c7e5eSwdenk
1204b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
1205c609719bSwdenk
120647cd00faSwdenk		CFG_I2C_INIT_BOARD
120747cd00faSwdenk
120847cd00faSwdenk		When a board is reset during an i2c bus transfer
120947cd00faSwdenk		chips might think that the current transfer is still
121047cd00faSwdenk		in progress. On some boards it is possible to access
121147cd00faSwdenk		the i2c SCLK line directly, either by using the
121247cd00faSwdenk		processor pin as a GPIO or by having a second pin
121347cd00faSwdenk		connected to the bus. If this option is defined a
121447cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
121547cd00faSwdenk		is run early in the boot sequence.
121647cd00faSwdenk
121717ea1177Swdenk		CONFIG_I2CFAST (PPC405GP|PPC405EP only)
121817ea1177Swdenk
121917ea1177Swdenk		This option enables configuration of bi_iic_fast[] flags
122017ea1177Swdenk		in u-boot bd_info structure based on u-boot environment
122117ea1177Swdenk		variable "i2cfast". (see also i2cfast)
122217ea1177Swdenk
1223c609719bSwdenk- SPI Support:	CONFIG_SPI
1224c609719bSwdenk
1225c609719bSwdenk		Enables SPI driver (so far only tested with
1226c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
1227c609719bSwdenk		D/As on the SACSng board)
1228c609719bSwdenk
1229c609719bSwdenk		CONFIG_SPI_X
1230c609719bSwdenk
1231c609719bSwdenk		Enables extended (16-bit) SPI EEPROM addressing.
1232c609719bSwdenk		(symmetrical to CONFIG_I2C_X)
1233c609719bSwdenk
1234c609719bSwdenk		CONFIG_SOFT_SPI
1235c609719bSwdenk
1236c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
1237c609719bSwdenk		using hardware support. This is a general purpose
1238c609719bSwdenk		driver that only requires three general I/O port pins
1239c609719bSwdenk		(two outputs, one input) to function. If this is
1240c609719bSwdenk		defined, the board configuration must define several
1241c609719bSwdenk		SPI configuration items (port pins to use, etc). For
1242c609719bSwdenk		an example, see include/configs/sacsng.h.
1243c609719bSwdenk
1244c609719bSwdenk- FPGA Support: CONFIG_FPGA_COUNT
1245c609719bSwdenk
1246c609719bSwdenk		Specify the number of FPGA devices to support.
1247c609719bSwdenk
1248c609719bSwdenk		CONFIG_FPGA
1249c609719bSwdenk
1250c609719bSwdenk		Used to specify the types of FPGA devices.  For example,
1251c609719bSwdenk		#define CONFIG_FPGA  CFG_XILINX_VIRTEX2
1252c609719bSwdenk
1253c609719bSwdenk		CFG_FPGA_PROG_FEEDBACK
1254c609719bSwdenk
1255c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
1256c609719bSwdenk
1257c609719bSwdenk		CFG_FPGA_CHECK_BUSY
1258c609719bSwdenk
1259c609719bSwdenk		Enable checks on FPGA configuration interface busy
1260c609719bSwdenk		status by the configuration function. This option
1261c609719bSwdenk		will require a board or device specific function to
1262c609719bSwdenk		be written.
1263c609719bSwdenk
1264c609719bSwdenk		CONFIG_FPGA_DELAY
1265c609719bSwdenk
1266c609719bSwdenk		If defined, a function that provides delays in the FPGA
1267c609719bSwdenk		configuration driver.
1268c609719bSwdenk
1269c609719bSwdenk		CFG_FPGA_CHECK_CTRLC
1270c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
1271c609719bSwdenk
1272c609719bSwdenk		CFG_FPGA_CHECK_ERROR
1273c609719bSwdenk
1274c609719bSwdenk		Check for configuration errors during FPGA bitfile
1275c609719bSwdenk		loading. For example, abort during Virtex II
1276c609719bSwdenk		configuration if the INIT_B line goes low (which
1277c609719bSwdenk		indicated a CRC error).
1278c609719bSwdenk
1279c609719bSwdenk		CFG_FPGA_WAIT_INIT
1280c609719bSwdenk
1281c609719bSwdenk		Maximum time to wait for the INIT_B line to deassert
1282c609719bSwdenk		after PROB_B has been deasserted during a Virtex II
1283c609719bSwdenk		FPGA configuration sequence. The default time is 500
1284c609719bSwdenk		mS.
1285c609719bSwdenk
1286c609719bSwdenk		CFG_FPGA_WAIT_BUSY
1287c609719bSwdenk
1288c609719bSwdenk		Maximum time to wait for BUSY to deassert during
1289c609719bSwdenk		Virtex II FPGA configuration. The default is 5 mS.
1290c609719bSwdenk
1291c609719bSwdenk		CFG_FPGA_WAIT_CONFIG
1292c609719bSwdenk
1293c609719bSwdenk		Time to wait after FPGA configuration. The default is
1294c609719bSwdenk		200 mS.
1295c609719bSwdenk
1296c609719bSwdenk- Configuration Management:
1297c609719bSwdenk		CONFIG_IDENT_STRING
1298c609719bSwdenk
1299c609719bSwdenk		If defined, this string will be added to the U-Boot
1300c609719bSwdenk		version information (U_BOOT_VERSION)
1301c609719bSwdenk
1302c609719bSwdenk- Vendor Parameter Protection:
1303c609719bSwdenk
1304c609719bSwdenk		U-Boot considers the values of the environment
1305c609719bSwdenk		variables "serial#" (Board Serial Number) and
13067152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
1307c609719bSwdenk		are set once by the board vendor / manufacturer, and
1308c609719bSwdenk		protects these variables from casual modification by
1309c609719bSwdenk		the user. Once set, these variables are read-only,
1310c609719bSwdenk		and write or delete attempts are rejected. You can
1311c609719bSwdenk		change this behviour:
1312c609719bSwdenk
1313c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
1314c609719bSwdenk		file, the write protection for vendor parameters is
131547cd00faSwdenk		completely disabled. Anybody can change or delete
1316c609719bSwdenk		these parameters.
1317c609719bSwdenk
1318c609719bSwdenk		Alternatively, if you #define _both_ CONFIG_ETHADDR
1319c609719bSwdenk		_and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1320c609719bSwdenk		ethernet address is installed in the environment,
1321c609719bSwdenk		which can be changed exactly ONCE by the user. [The
1322c609719bSwdenk		serial# is unaffected by this, i. e. it remains
1323c609719bSwdenk		read-only.]
1324c609719bSwdenk
1325c609719bSwdenk- Protected RAM:
1326c609719bSwdenk		CONFIG_PRAM
1327c609719bSwdenk
1328c609719bSwdenk		Define this variable to enable the reservation of
1329c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
1330c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
1331c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
1332c609719bSwdenk		this default value by defining an environment
1333c609719bSwdenk		variable "pram" to the number of kB you want to
1334c609719bSwdenk		reserve. Note that the board info structure will
1335c609719bSwdenk		still show the full amount of RAM. If pRAM is
1336c609719bSwdenk		reserved, a new environment variable "mem" will
1337c609719bSwdenk		automatically be defined to hold the amount of
1338c609719bSwdenk		remaining RAM in a form that can be passed as boot
1339c609719bSwdenk		argument to Linux, for instance like that:
1340c609719bSwdenk
1341c609719bSwdenk			setenv bootargs ... mem=\$(mem)
1342c609719bSwdenk			saveenv
1343c609719bSwdenk
1344c609719bSwdenk		This way you can tell Linux not to use this memory,
1345c609719bSwdenk		either, which results in a memory region that will
1346c609719bSwdenk		not be affected by reboots.
1347c609719bSwdenk
1348c609719bSwdenk		*WARNING* If your board configuration uses automatic
1349c609719bSwdenk		detection of the RAM size, you must make sure that
1350c609719bSwdenk		this memory test is non-destructive. So far, the
1351c609719bSwdenk		following board configurations are known to be
1352c609719bSwdenk		"pRAM-clean":
1353c609719bSwdenk
1354c609719bSwdenk			ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1355c609719bSwdenk			HERMES, IP860, RPXlite, LWMON, LANTEC,
1356c609719bSwdenk			PCU_E, FLAGADM, TQM8260
1357c609719bSwdenk
1358c609719bSwdenk- Error Recovery:
1359c609719bSwdenk		CONFIG_PANIC_HANG
1360c609719bSwdenk
1361c609719bSwdenk		Define this variable to stop the system in case of a
1362c609719bSwdenk		fatal error, so that you have to reset it manually.
1363c609719bSwdenk		This is probably NOT a good idea for an embedded
1364c609719bSwdenk		system where you want to system to reboot
1365c609719bSwdenk		automatically as fast as possible, but it may be
1366c609719bSwdenk		useful during development since you can try to debug
1367c609719bSwdenk		the conditions that lead to the situation.
1368c609719bSwdenk
1369c609719bSwdenk		CONFIG_NET_RETRY_COUNT
1370c609719bSwdenk
1371c609719bSwdenk		This variable defines the number of retries for
1372c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
1373c609719bSwdenk		before giving up the operation. If not defined, a
1374c609719bSwdenk		default value of 5 is used.
1375c609719bSwdenk
1376c609719bSwdenk- Command Interpreter:
137704a85b3bSwdenk		CFG_AUTO_COMPLETE
137804a85b3bSwdenk
137904a85b3bSwdenk		Enable auto completion of commands using TAB.
138004a85b3bSwdenk
1381c609719bSwdenk		CFG_HUSH_PARSER
1382c609719bSwdenk
1383c609719bSwdenk		Define this variable to enable the "hush" shell (from
1384c609719bSwdenk		Busybox) as command line interpreter, thus enabling
1385c609719bSwdenk		powerful command line syntax like
1386c609719bSwdenk		if...then...else...fi conditionals or `&&' and '||'
1387c609719bSwdenk		constructs ("shell scripts").
1388c609719bSwdenk
1389c609719bSwdenk		If undefined, you get the old, much simpler behaviour
1390c609719bSwdenk		with a somewhat smaller memory footprint.
1391c609719bSwdenk
1392c609719bSwdenk
1393c609719bSwdenk		CFG_PROMPT_HUSH_PS2
1394c609719bSwdenk
1395c609719bSwdenk		This defines the secondary prompt string, which is
1396c609719bSwdenk		printed when the command interpreter needs more input
1397c609719bSwdenk		to complete a command. Usually "> ".
1398c609719bSwdenk
1399c609719bSwdenk	Note:
1400c609719bSwdenk
1401c609719bSwdenk		In the current implementation, the local variables
1402c609719bSwdenk		space and global environment variables space are
1403c609719bSwdenk		separated. Local variables are those you define by
14043b57fe0aSwdenk		simply typing `name=value'. To access a local
1405c609719bSwdenk		variable later on, you have write `$name' or
14063b57fe0aSwdenk		`${name}'; to execute the contents of a variable
14073b57fe0aSwdenk		directly type `$name' at the command prompt.
1408c609719bSwdenk
1409c609719bSwdenk		Global environment variables are those you use
1410c609719bSwdenk		setenv/printenv to work with. To run a command stored
1411c609719bSwdenk		in such a variable, you need to use the run command,
1412c609719bSwdenk		and you must not use the '$' sign to access them.
1413c609719bSwdenk
1414c609719bSwdenk		To store commands and special characters in a
1415c609719bSwdenk		variable, please use double quotation marks
1416c609719bSwdenk		surrounding the whole text of the variable, instead
1417c609719bSwdenk		of the backslashes before semicolons and special
1418c609719bSwdenk		symbols.
1419c609719bSwdenk
1420a8c7c708Swdenk- Default Environment:
1421c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
1422c609719bSwdenk
1423c609719bSwdenk		Define this to contain any number of null terminated
1424c609719bSwdenk		strings (variable = value pairs) that will be part of
14257152b1d0Swdenk		the default environment compiled into the boot image.
14262262cfeeSwdenk
1427c609719bSwdenk		For example, place something like this in your
1428c609719bSwdenk		board's config file:
1429c609719bSwdenk
1430c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
1431c609719bSwdenk			"myvar1=value1\0" \
1432c609719bSwdenk			"myvar2=value2\0"
1433c609719bSwdenk
1434c609719bSwdenk		Warning: This method is based on knowledge about the
1435c609719bSwdenk		internal format how the environment is stored by the
14362262cfeeSwdenk		U-Boot code. This is NOT an official, exported
1437c609719bSwdenk		interface! Although it is unlikely that this format
14387152b1d0Swdenk		will change soon, there is no guarantee either.
1439c609719bSwdenk		You better know what you are doing here.
1440c609719bSwdenk
1441c609719bSwdenk		Note: overly (ab)use of the default environment is
1442c609719bSwdenk		discouraged. Make sure to check other ways to preset
1443c609719bSwdenk		the environment like the autoscript function or the
1444c609719bSwdenk		boot command first.
1445c609719bSwdenk
1446a8c7c708Swdenk- DataFlash Support:
14472abbe075Swdenk		CONFIG_HAS_DATAFLASH
14482abbe075Swdenk
14492abbe075Swdenk		Defining this option enables DataFlash features and
14502abbe075Swdenk		allows to read/write in Dataflash via the standard
14512abbe075Swdenk		commands cp, md...
14522abbe075Swdenk
14533f85ce27Swdenk- SystemACE Support:
14543f85ce27Swdenk		CONFIG_SYSTEMACE
14553f85ce27Swdenk
14563f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
14573f85ce27Swdenk		chips attached via some sort of local bus. The address
14583f85ce27Swdenk		of the chip must alsh be defined in the
14593f85ce27Swdenk		CFG_SYSTEMACE_BASE macro. For example:
14603f85ce27Swdenk
14613f85ce27Swdenk		#define CONFIG_SYSTEMACE
14623f85ce27Swdenk		#define CFG_SYSTEMACE_BASE 0xf0000000
14633f85ce27Swdenk
14643f85ce27Swdenk		When SystemACE support is added, the "ace" device type
14653f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
14663f85ce27Swdenk
1467a8c7c708Swdenk- Show boot progress:
1468c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
1469c609719bSwdenk
1470c609719bSwdenk		Defining this option allows to add some board-
1471c609719bSwdenk		specific code (calling a user-provided function
1472c609719bSwdenk		"show_boot_progress(int)") that enables you to show
1473c609719bSwdenk		the system's boot progress on some display (for
1474c609719bSwdenk		example, some LED's) on your board. At the moment,
1475c609719bSwdenk		the following checkpoints are implemented:
1476c609719bSwdenk
1477c609719bSwdenk  Arg	Where			When
1478c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
1479c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
1480c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
1481c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
1482c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
1483c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
1484c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
1485c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
1486c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
1487c609719bSwdenk   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi, standalone)
1488c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
1489c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
1490c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
1491c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
1492c609719bSwdenk   -8	common/cmd_bootm.c	Wrong Image Type (not kernel, multi, standalone)
1493c609719bSwdenk    8	common/cmd_bootm.c	Image Type check OK
1494c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
1495c609719bSwdenk    9	common/cmd_bootm.c	Start initial ramdisk verification
1496c609719bSwdenk  -10	common/cmd_bootm.c	Ramdisk header has bad	   magic number
1497c609719bSwdenk  -11	common/cmd_bootm.c	Ramdisk header has bad	   checksum
1498c609719bSwdenk   10	common/cmd_bootm.c	Ramdisk header is OK
1499c609719bSwdenk  -12	common/cmd_bootm.c	Ramdisk data   has bad	   checksum
1500c609719bSwdenk   11	common/cmd_bootm.c	Ramdisk data   has correct checksum
1501c609719bSwdenk   12	common/cmd_bootm.c	Ramdisk verification complete, start loading
1502c609719bSwdenk  -13	common/cmd_bootm.c	Wrong Image Type (not PPC Linux Ramdisk)
1503c609719bSwdenk   13	common/cmd_bootm.c	Start multifile image verification
1504c609719bSwdenk   14	common/cmd_bootm.c	No initial ramdisk, no multifile, continue.
1505c609719bSwdenk   15	common/cmd_bootm.c	All preparation done, transferring control to OS
1506c609719bSwdenk
150763e73c9aSwdenk  -30	lib_ppc/board.c		Fatal error, hang the system
150863e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
150963e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
151063e73c9aSwdenk
1511c609719bSwdenk   -1	common/cmd_doc.c	Bad usage of "doc" command
1512c609719bSwdenk   -1	common/cmd_doc.c	No boot device
1513c609719bSwdenk   -1	common/cmd_doc.c	Unknown Chip ID on boot device
1514c609719bSwdenk   -1	common/cmd_doc.c	Read Error on boot device
1515c609719bSwdenk   -1	common/cmd_doc.c	Image header has bad magic number
1516c609719bSwdenk
1517c609719bSwdenk   -1	common/cmd_ide.c	Bad usage of "ide" command
1518c609719bSwdenk   -1	common/cmd_ide.c	No boot device
1519c609719bSwdenk   -1	common/cmd_ide.c	Unknown boot device
1520c609719bSwdenk   -1	common/cmd_ide.c	Unknown partition table
1521c609719bSwdenk   -1	common/cmd_ide.c	Invalid partition type
1522c609719bSwdenk   -1	common/cmd_ide.c	Read Error on boot device
1523c609719bSwdenk   -1	common/cmd_ide.c	Image header has bad magic number
1524c609719bSwdenk
1525206c60cbSwdenk   -1	common/cmd_nand.c	Bad usage of "nand" command
1526206c60cbSwdenk   -1	common/cmd_nand.c	No boot device
1527206c60cbSwdenk   -1	common/cmd_nand.c	Unknown Chip ID on boot device
1528206c60cbSwdenk   -1	common/cmd_nand.c	Read Error on boot device
1529206c60cbSwdenk   -1	common/cmd_nand.c	Image header has bad magic number
1530206c60cbSwdenk
1531206c60cbSwdenk   -1	common/env_common.c	Environment has a bad CRC, using default
1532c609719bSwdenk
1533c609719bSwdenk
1534c609719bSwdenkModem Support:
1535c609719bSwdenk--------------
1536c609719bSwdenk
153785ec0bccSwdenk[so far only for SMDK2400 and TRAB boards]
1538c609719bSwdenk
1539c609719bSwdenk- Modem support endable:
1540c609719bSwdenk		CONFIG_MODEM_SUPPORT
1541c609719bSwdenk
1542c609719bSwdenk- RTS/CTS Flow control enable:
1543c609719bSwdenk		CONFIG_HWFLOW
1544c609719bSwdenk
1545c609719bSwdenk- Modem debug support:
1546c609719bSwdenk		CONFIG_MODEM_SUPPORT_DEBUG
1547c609719bSwdenk
1548c609719bSwdenk		Enables debugging stuff (char screen[1024], dbg())
1549c609719bSwdenk		for modem support. Useful only with BDI2000.
1550c609719bSwdenk
1551a8c7c708Swdenk- Interrupt support (PPC):
1552a8c7c708Swdenk
1553a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
1554a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1555a8c7c708Swdenk		for cpu specific initialization. interrupt_init_cpu()
1556a8c7c708Swdenk		should set decrementer_count to appropriate value. If
1557a8c7c708Swdenk		cpu resets decrementer automatically after interrupt
1558a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
1559a8c7c708Swdenk		timer_interrupt() calls timer_interrupt_cpu() for cpu
1560a8c7c708Swdenk		specific handling. If board has watchdog / status_led
1561a8c7c708Swdenk		/ other_activity_monitor it works automatically from
1562a8c7c708Swdenk		general timer_interrupt().
1563a8c7c708Swdenk
1564c609719bSwdenk- General:
1565c609719bSwdenk
1566c609719bSwdenk		In the target system modem support is enabled when a
1567c609719bSwdenk		specific key (key combination) is pressed during
1568c609719bSwdenk		power-on. Otherwise U-Boot will boot normally
1569c609719bSwdenk		(autoboot). The key_pressed() fuction is called from
1570c609719bSwdenk		board_init(). Currently key_pressed() is a dummy
1571c609719bSwdenk		function, returning 1 and thus enabling modem
1572c609719bSwdenk		initialization.
1573c609719bSwdenk
1574c609719bSwdenk		If there are no modem init strings in the
1575c609719bSwdenk		environment, U-Boot proceed to autoboot; the
1576c609719bSwdenk		previous output (banner, info printfs) will be
1577c609719bSwdenk		supressed, though.
1578c609719bSwdenk
1579c609719bSwdenk		See also: doc/README.Modem
1580c609719bSwdenk
1581c609719bSwdenk
1582c609719bSwdenkConfiguration Settings:
1583c609719bSwdenk-----------------------
1584c609719bSwdenk
1585c609719bSwdenk- CFG_LONGHELP: Defined when you want long help messages included;
1586c609719bSwdenk		undefine this when you're short of memory.
1587c609719bSwdenk
1588c609719bSwdenk- CFG_PROMPT:	This is what U-Boot prints on the console to
1589c609719bSwdenk		prompt for user input.
1590c609719bSwdenk
1591c609719bSwdenk- CFG_CBSIZE:	Buffer size for input from the Console
1592c609719bSwdenk
1593c609719bSwdenk- CFG_PBSIZE:	Buffer size for Console output
1594c609719bSwdenk
1595c609719bSwdenk- CFG_MAXARGS:	max. Number of arguments accepted for monitor commands
1596c609719bSwdenk
1597c609719bSwdenk- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1598c609719bSwdenk		the application (usually a Linux kernel) when it is
1599c609719bSwdenk		booted
1600c609719bSwdenk
1601c609719bSwdenk- CFG_BAUDRATE_TABLE:
1602c609719bSwdenk		List of legal baudrate settings for this board.
1603c609719bSwdenk
1604c609719bSwdenk- CFG_CONSOLE_INFO_QUIET
1605c609719bSwdenk		Suppress display of console information at boot.
1606c609719bSwdenk
1607c609719bSwdenk- CFG_CONSOLE_IS_IN_ENV
1608c609719bSwdenk		If the board specific function
1609c609719bSwdenk			extern int overwrite_console (void);
1610c609719bSwdenk		returns 1, the stdin, stderr and stdout are switched to the
1611c609719bSwdenk		serial port, else the settings in the environment are used.
1612c609719bSwdenk
1613c609719bSwdenk- CFG_CONSOLE_OVERWRITE_ROUTINE
1614c609719bSwdenk		Enable the call to overwrite_console().
1615c609719bSwdenk
1616c609719bSwdenk- CFG_CONSOLE_ENV_OVERWRITE
1617c609719bSwdenk		Enable overwrite of previous console environment settings.
1618c609719bSwdenk
1619c609719bSwdenk- CFG_MEMTEST_START, CFG_MEMTEST_END:
1620c609719bSwdenk		Begin and End addresses of the area used by the
1621c609719bSwdenk		simple memory test.
1622c609719bSwdenk
1623c609719bSwdenk- CFG_ALT_MEMTEST:
1624c609719bSwdenk		Enable an alternate, more extensive memory test.
1625c609719bSwdenk
16265f535fe1Swdenk- CFG_MEMTEST_SCRATCH:
16275f535fe1Swdenk		Scratch address used by the alternate memory test
16285f535fe1Swdenk		You only need to set this if address zero isn't writeable
16295f535fe1Swdenk
1630c609719bSwdenk- CFG_TFTP_LOADADDR:
1631c609719bSwdenk		Default load address for network file downloads
1632c609719bSwdenk
1633c609719bSwdenk- CFG_LOADS_BAUD_CHANGE:
1634c609719bSwdenk		Enable temporary baudrate change while serial download
1635c609719bSwdenk
1636c609719bSwdenk- CFG_SDRAM_BASE:
1637c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
1638c609719bSwdenk
1639c609719bSwdenk- CFG_MBIO_BASE:
1640c609719bSwdenk		Physical start address of Motherboard I/O (if using a
1641c609719bSwdenk		Cogent motherboard)
1642c609719bSwdenk
1643c609719bSwdenk- CFG_FLASH_BASE:
1644c609719bSwdenk		Physical start address of Flash memory.
1645c609719bSwdenk
1646c609719bSwdenk- CFG_MONITOR_BASE:
1647c609719bSwdenk		Physical start address of boot monitor code (set by
1648c609719bSwdenk		make config files to be same as the text base address
1649c609719bSwdenk		(TEXT_BASE) used when linking) - same as
1650c609719bSwdenk		CFG_FLASH_BASE when booting from flash.
1651c609719bSwdenk
1652c609719bSwdenk- CFG_MONITOR_LEN:
16533b57fe0aSwdenk		Size of memory reserved for monitor code, used to
16543b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
16553b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
16563b57fe0aSwdenk		flash sector.
1657c609719bSwdenk
1658c609719bSwdenk- CFG_MALLOC_LEN:
1659c609719bSwdenk		Size of DRAM reserved for malloc() use.
1660c609719bSwdenk
1661c609719bSwdenk- CFG_BOOTMAPSZ:
1662c609719bSwdenk		Maximum size of memory mapped by the startup code of
1663c609719bSwdenk		the Linux kernel; all data that must be processed by
1664c609719bSwdenk		the Linux kernel (bd_info, boot arguments, eventually
1665c609719bSwdenk		initrd image) must be put below this limit.
1666c609719bSwdenk
1667c609719bSwdenk- CFG_MAX_FLASH_BANKS:
1668c609719bSwdenk		Max number of Flash memory banks
1669c609719bSwdenk
1670c609719bSwdenk- CFG_MAX_FLASH_SECT:
1671c609719bSwdenk		Max number of sectors on a Flash chip
1672c609719bSwdenk
1673c609719bSwdenk- CFG_FLASH_ERASE_TOUT:
1674c609719bSwdenk		Timeout for Flash erase operations (in ms)
1675c609719bSwdenk
1676c609719bSwdenk- CFG_FLASH_WRITE_TOUT:
1677c609719bSwdenk		Timeout for Flash write operations (in ms)
1678c609719bSwdenk
16798564acf9Swdenk- CFG_FLASH_LOCK_TOUT
16808564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
16818564acf9Swdenk
16828564acf9Swdenk- CFG_FLASH_UNLOCK_TOUT
16838564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
16848564acf9Swdenk
16858564acf9Swdenk- CFG_FLASH_PROTECTION
16868564acf9Swdenk		If defined, hardware flash sectors protection is used
16878564acf9Swdenk		instead of U-Boot software protection.
16888564acf9Swdenk
1689c609719bSwdenk- CFG_DIRECT_FLASH_TFTP:
1690c609719bSwdenk
1691c609719bSwdenk		Enable TFTP transfers directly to flash memory;
1692c609719bSwdenk		without this option such a download has to be
1693c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
1694c609719bSwdenk		copy from RAM to flash.
1695c609719bSwdenk
1696c609719bSwdenk		The two-step approach is usually more reliable, since
1697c609719bSwdenk		you can check if the download worked before you erase
1698c609719bSwdenk		the flash, but in some situations (when sytem RAM is
1699c609719bSwdenk		too limited to allow for a tempory copy of the
1700c609719bSwdenk		downloaded image) this option may be very useful.
1701c609719bSwdenk
1702c609719bSwdenk- CFG_FLASH_CFI:
1703c609719bSwdenk		Define if the flash driver uses extra elements in the
17045653fc33Swdenk		common flash structure for storing flash geometry.
17055653fc33Swdenk
17065653fc33Swdenk- CFG_FLASH_CFI_DRIVER
17075653fc33Swdenk		This option also enables the building of the cfi_flash driver
17085653fc33Swdenk		in the drivers directory
170953cf9435Sstroese
171053cf9435Sstroese- CFG_RX_ETH_BUFFER:
171153cf9435Sstroese		Defines the number of ethernet receive buffers. On some
171253cf9435Sstroese		ethernet controllers it is recommended to set this value
171353cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
171453cf9435Sstroese		buffers can be full shortly after enabling the interface
171553cf9435Sstroese		on high ethernet traffic.
171653cf9435Sstroese		Defaults to 4 if not defined.
1717c609719bSwdenk
1718c609719bSwdenkThe following definitions that deal with the placement and management
1719c609719bSwdenkof environment data (variable area); in general, we support the
1720c609719bSwdenkfollowing configurations:
1721c609719bSwdenk
1722c609719bSwdenk- CFG_ENV_IS_IN_FLASH:
1723c609719bSwdenk
1724c609719bSwdenk	Define this if the environment is in flash memory.
1725c609719bSwdenk
1726c609719bSwdenk	a) The environment occupies one whole flash sector, which is
1727c609719bSwdenk	   "embedded" in the text segment with the U-Boot code. This
1728c609719bSwdenk	   happens usually with "bottom boot sector" or "top boot
1729c609719bSwdenk	   sector" type flash chips, which have several smaller
1730c609719bSwdenk	   sectors at the start or the end. For instance, such a
1731c609719bSwdenk	   layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1732c609719bSwdenk	   such a case you would place the environment in one of the
1733c609719bSwdenk	   4 kB sectors - with U-Boot code before and after it. With
1734c609719bSwdenk	   "top boot sector" type flash chips, you would put the
1735c609719bSwdenk	   environment in one of the last sectors, leaving a gap
1736c609719bSwdenk	   between U-Boot and the environment.
1737c609719bSwdenk
1738c609719bSwdenk	- CFG_ENV_OFFSET:
1739c609719bSwdenk
1740c609719bSwdenk	   Offset of environment data (variable area) to the
1741c609719bSwdenk	   beginning of flash memory; for instance, with bottom boot
1742c609719bSwdenk	   type flash chips the second sector can be used: the offset
1743c609719bSwdenk	   for this sector is given here.
1744c609719bSwdenk
1745c609719bSwdenk	   CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1746c609719bSwdenk
1747c609719bSwdenk	- CFG_ENV_ADDR:
1748c609719bSwdenk
1749c609719bSwdenk	   This is just another way to specify the start address of
1750c609719bSwdenk	   the flash sector containing the environment (instead of
1751c609719bSwdenk	   CFG_ENV_OFFSET).
1752c609719bSwdenk
1753c609719bSwdenk	- CFG_ENV_SECT_SIZE:
1754c609719bSwdenk
1755c609719bSwdenk	   Size of the sector containing the environment.
1756c609719bSwdenk
1757c609719bSwdenk
1758c609719bSwdenk	b) Sometimes flash chips have few, equal sized, BIG sectors.
1759c609719bSwdenk	   In such a case you don't want to spend a whole sector for
1760c609719bSwdenk	   the environment.
1761c609719bSwdenk
1762c609719bSwdenk	- CFG_ENV_SIZE:
1763c609719bSwdenk
1764c609719bSwdenk	   If you use this in combination with CFG_ENV_IS_IN_FLASH
1765c609719bSwdenk	   and CFG_ENV_SECT_SIZE, you can specify to use only a part
1766c609719bSwdenk	   of this flash sector for the environment. This saves
1767c609719bSwdenk	   memory for the RAM copy of the environment.
1768c609719bSwdenk
1769c609719bSwdenk	   It may also save flash memory if you decide to use this
1770c609719bSwdenk	   when your environment is "embedded" within U-Boot code,
1771c609719bSwdenk	   since then the remainder of the flash sector could be used
1772c609719bSwdenk	   for U-Boot code. It should be pointed out that this is
1773c609719bSwdenk	   STRONGLY DISCOURAGED from a robustness point of view:
1774c609719bSwdenk	   updating the environment in flash makes it always
1775c609719bSwdenk	   necessary to erase the WHOLE sector. If something goes
1776c609719bSwdenk	   wrong before the contents has been restored from a copy in
1777c609719bSwdenk	   RAM, your target system will be dead.
1778c609719bSwdenk
1779c609719bSwdenk	- CFG_ENV_ADDR_REDUND
1780c609719bSwdenk	  CFG_ENV_SIZE_REDUND
1781c609719bSwdenk
1782c609719bSwdenk	   These settings describe a second storage area used to hold
1783c609719bSwdenk	   a redundand copy of the environment data, so that there is
17843e38691eSwdenk	   a valid backup copy in case there is a power failure during
1785c609719bSwdenk	   a "saveenv" operation.
1786c609719bSwdenk
1787c609719bSwdenkBE CAREFUL! Any changes to the flash layout, and some changes to the
1788c609719bSwdenksource code will make it necessary to adapt <board>/u-boot.lds*
1789c609719bSwdenkaccordingly!
1790c609719bSwdenk
1791c609719bSwdenk
1792c609719bSwdenk- CFG_ENV_IS_IN_NVRAM:
1793c609719bSwdenk
1794c609719bSwdenk	Define this if you have some non-volatile memory device
1795c609719bSwdenk	(NVRAM, battery buffered SRAM) which you want to use for the
1796c609719bSwdenk	environment.
1797c609719bSwdenk
1798c609719bSwdenk	- CFG_ENV_ADDR:
1799c609719bSwdenk	- CFG_ENV_SIZE:
1800c609719bSwdenk
1801c609719bSwdenk	  These two #defines are used to determin the memory area you
1802c609719bSwdenk	  want to use for environment. It is assumed that this memory
1803c609719bSwdenk	  can just be read and written to, without any special
1804c609719bSwdenk	  provision.
1805c609719bSwdenk
1806c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
1807c609719bSwdenkin U-Boot initalization (when we try to get the setting of for the
1808c609719bSwdenkconsole baudrate). You *MUST* have mappend your NVRAM area then, or
1809c609719bSwdenkU-Boot will hang.
1810c609719bSwdenk
1811c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
1812c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
1813c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
1814c609719bSwdenkto save the current settings.
1815c609719bSwdenk
1816c609719bSwdenk
1817c609719bSwdenk- CFG_ENV_IS_IN_EEPROM:
1818c609719bSwdenk
1819c609719bSwdenk	Use this if you have an EEPROM or similar serial access
1820c609719bSwdenk	device and a driver for it.
1821c609719bSwdenk
1822c609719bSwdenk	- CFG_ENV_OFFSET:
1823c609719bSwdenk	- CFG_ENV_SIZE:
1824c609719bSwdenk
1825c609719bSwdenk	  These two #defines specify the offset and size of the
1826c609719bSwdenk	  environment area within the total memory of your EEPROM.
1827c609719bSwdenk
1828c609719bSwdenk	- CFG_I2C_EEPROM_ADDR:
1829c609719bSwdenk	  If defined, specified the chip address of the EEPROM device.
1830c609719bSwdenk	  The default address is zero.
1831c609719bSwdenk
1832c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_BITS:
1833c609719bSwdenk	  If defined, the number of bits used to address bytes in a
1834c609719bSwdenk	  single page in the EEPROM device.  A 64 byte page, for example
1835c609719bSwdenk	  would require six bits.
1836c609719bSwdenk
1837c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1838c609719bSwdenk	  If defined, the number of milliseconds to delay between
1839c609719bSwdenk	  page writes.	The default is zero milliseconds.
1840c609719bSwdenk
1841c609719bSwdenk	- CFG_I2C_EEPROM_ADDR_LEN:
1842c609719bSwdenk	  The length in bytes of the EEPROM memory array address.  Note
1843c609719bSwdenk	  that this is NOT the chip address length!
1844c609719bSwdenk
18455cf91d6bSwdenk	- CFG_I2C_EEPROM_ADDR_OVERFLOW:
18465cf91d6bSwdenk	  EEPROM chips that implement "address overflow" are ones
18475cf91d6bSwdenk	  like Catalyst 24WC04/08/16 which has 9/10/11 bits of
18485cf91d6bSwdenk	  address and the extra bits end up in the "chip address" bit
18495cf91d6bSwdenk	  slots. This makes a 24WC08 (1Kbyte) chip look like four 256
18505cf91d6bSwdenk	  byte chips.
18515cf91d6bSwdenk
18525cf91d6bSwdenk	  Note that we consider the length of the address field to
18535cf91d6bSwdenk	  still be one byte because the extra address bits are hidden
18545cf91d6bSwdenk	  in the chip address.
18555cf91d6bSwdenk
1856c609719bSwdenk	- CFG_EEPROM_SIZE:
1857c609719bSwdenk	  The size in bytes of the EEPROM device.
1858c609719bSwdenk
1859c609719bSwdenk
18605779d8d9Swdenk- CFG_ENV_IS_IN_DATAFLASH:
18615779d8d9Swdenk
18625779d8d9Swdenk	Define this if you have a DataFlash memory device which you
18635779d8d9Swdenk	want to use for the environment.
18645779d8d9Swdenk
18655779d8d9Swdenk	- CFG_ENV_OFFSET:
18665779d8d9Swdenk	- CFG_ENV_ADDR:
18675779d8d9Swdenk	- CFG_ENV_SIZE:
18685779d8d9Swdenk
18695779d8d9Swdenk	  These three #defines specify the offset and size of the
18705779d8d9Swdenk	  environment area within the total memory of your DataFlash placed
18715779d8d9Swdenk	  at the specified address.
18725779d8d9Swdenk
187313a5695bSwdenk- CFG_ENV_IS_IN_NAND:
187413a5695bSwdenk
187513a5695bSwdenk	Define this if you have a NAND device which you want to use
187613a5695bSwdenk	for the environment.
187713a5695bSwdenk
187813a5695bSwdenk	- CFG_ENV_OFFSET:
187913a5695bSwdenk	- CFG_ENV_SIZE:
188013a5695bSwdenk
188113a5695bSwdenk	  These two #defines specify the offset and size of the environment
188213a5695bSwdenk	  area within the first NAND device.
18835779d8d9Swdenk
1884c609719bSwdenk- CFG_SPI_INIT_OFFSET
1885c609719bSwdenk
1886c609719bSwdenk	Defines offset to the initial SPI buffer area in DPRAM. The
1887c609719bSwdenk	area is used at an early stage (ROM part) if the environment
1888c609719bSwdenk	is configured to reside in the SPI EEPROM: We need a 520 byte
1889c609719bSwdenk	scratch DPRAM area. It is used between the two initialization
1890c609719bSwdenk	calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1891c609719bSwdenk	to be a good choice since it makes it far enough from the
1892c609719bSwdenk	start of the data area as well as from the stack pointer.
1893c609719bSwdenk
1894c609719bSwdenkPlease note that the environment is read-only as long as the monitor
1895c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
1896c609719bSwdenkcreated; also, when using EEPROM you will have to use getenv_r()
1897c609719bSwdenkuntil then to read environment variables.
1898c609719bSwdenk
189985ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
190085ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
190185ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
190285ec0bccSwdenknecessary, because the first environment variable we need is the
190385ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
190485ec0bccSwdenkhave any device yet where we could complain.]
1905c609719bSwdenk
1906c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
1907c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
190885ec0bccSwdenkuse the "saveenv" command to store a valid environment.
1909c609719bSwdenk
1910fc3e2165Swdenk- CFG_FAULT_ECHO_LINK_DOWN:
1911fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
1912fc3e2165Swdenk
1913fc3e2165Swdenk		Note: If this option is active, then CFG_FAULT_MII_ADDR
1914fc3e2165Swdenk		      also needs to be defined.
1915fc3e2165Swdenk
1916fc3e2165Swdenk- CFG_FAULT_MII_ADDR:
1917fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
1918c609719bSwdenk
1919c40b2956Swdenk- CFG_64BIT_VSPRINTF:
1920c40b2956Swdenk		Makes vsprintf (and all *printf functions) support printing
1921c40b2956Swdenk		of 64bit values by using the L quantifier
1922c40b2956Swdenk
1923c40b2956Swdenk- CFG_64BIT_STRTOUL:
1924c40b2956Swdenk		Adds simple_strtoull that returns a 64bit value
1925c40b2956Swdenk
1926c609719bSwdenkLow Level (hardware related) configuration options:
1927dc7c9a1aSwdenk---------------------------------------------------
1928c609719bSwdenk
1929c609719bSwdenk- CFG_CACHELINE_SIZE:
1930c609719bSwdenk		Cache Line Size of the CPU.
1931c609719bSwdenk
1932c609719bSwdenk- CFG_DEFAULT_IMMR:
1933c609719bSwdenk		Default address of the IMMR after system reset.
19342535d602Swdenk
19352535d602Swdenk		Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
19362535d602Swdenk		and RPXsuper) to be able to adjust the position of
19372535d602Swdenk		the IMMR register after a reset.
1938c609719bSwdenk
19397f6c2cbcSwdenk- Floppy Disk Support:
19407f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER
19417f6c2cbcSwdenk
19427f6c2cbcSwdenk		the default drive number (default value 0)
19437f6c2cbcSwdenk
19447f6c2cbcSwdenk		CFG_ISA_IO_STRIDE
19457f6c2cbcSwdenk
19467f6c2cbcSwdenk		defines the spacing between fdc chipset registers
19477f6c2cbcSwdenk		(default value 1)
19487f6c2cbcSwdenk
19497f6c2cbcSwdenk		CFG_ISA_IO_OFFSET
19507f6c2cbcSwdenk
19517f6c2cbcSwdenk		defines the offset of register from address. It
19527f6c2cbcSwdenk		depends on which part of the data bus is connected to
19537f6c2cbcSwdenk		the fdc chipset. (default value 0)
19547f6c2cbcSwdenk
19557f6c2cbcSwdenk		If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
19567f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER are undefined, they take their
19577f6c2cbcSwdenk		default value.
19587f6c2cbcSwdenk
19597f6c2cbcSwdenk		if CFG_FDC_HW_INIT is defined, then the function
19607f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
19617f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
19627f6c2cbcSwdenk		source code. It is used to make hardware dependant
19637f6c2cbcSwdenk		initializations.
19647f6c2cbcSwdenk
1965c609719bSwdenk- CFG_IMMR:	Physical address of the Internal Memory Mapped
1966c609719bSwdenk		Register; DO NOT CHANGE! (11-4)
1967c609719bSwdenk		[MPC8xx systems only]
1968c609719bSwdenk
1969c609719bSwdenk- CFG_INIT_RAM_ADDR:
1970c609719bSwdenk
19717152b1d0Swdenk		Start address of memory area that can be used for
1972c609719bSwdenk		initial data and stack; please note that this must be
1973c609719bSwdenk		writable memory that is working WITHOUT special
1974c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
1975c609719bSwdenk		will become available only after programming the
1976c609719bSwdenk		memory controller and running certain initialization
1977c609719bSwdenk		sequences.
1978c609719bSwdenk
1979c609719bSwdenk		U-Boot uses the following memory types:
1980c609719bSwdenk		- MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1981c609719bSwdenk		- MPC824X: data cache
1982c609719bSwdenk		- PPC4xx:  data cache
1983c609719bSwdenk
198485ec0bccSwdenk- CFG_GBL_DATA_OFFSET:
1985c609719bSwdenk
1986c609719bSwdenk		Offset of the initial data structure in the memory
1987c609719bSwdenk		area defined by CFG_INIT_RAM_ADDR. Usually
198885ec0bccSwdenk		CFG_GBL_DATA_OFFSET is chosen such that the initial
1989c609719bSwdenk		data is located at the end of the available space
1990c609719bSwdenk		(sometimes written as (CFG_INIT_RAM_END -
1991c609719bSwdenk		CFG_INIT_DATA_SIZE), and the initial stack is just
1992c609719bSwdenk		below that area (growing from (CFG_INIT_RAM_ADDR +
199385ec0bccSwdenk		CFG_GBL_DATA_OFFSET) downward.
1994c609719bSwdenk
1995c609719bSwdenk	Note:
1996c609719bSwdenk		On the MPC824X (or other systems that use the data
1997c609719bSwdenk		cache for initial memory) the address chosen for
1998c609719bSwdenk		CFG_INIT_RAM_ADDR is basically arbitrary - it must
1999c609719bSwdenk		point to an otherwise UNUSED address space between
2000c609719bSwdenk		the top of RAM and the start of the PCI space.
2001c609719bSwdenk
2002c609719bSwdenk- CFG_SIUMCR:	SIU Module Configuration (11-6)
2003c609719bSwdenk
2004c609719bSwdenk- CFG_SYPCR:	System Protection Control (11-9)
2005c609719bSwdenk
2006c609719bSwdenk- CFG_TBSCR:	Time Base Status and Control (11-26)
2007c609719bSwdenk
2008c609719bSwdenk- CFG_PISCR:	Periodic Interrupt Status and Control (11-31)
2009c609719bSwdenk
2010c609719bSwdenk- CFG_PLPRCR:	PLL, Low-Power, and Reset Control Register (15-30)
2011c609719bSwdenk
2012c609719bSwdenk- CFG_SCCR:	System Clock and reset Control Register (15-27)
2013c609719bSwdenk
2014c609719bSwdenk- CFG_OR_TIMING_SDRAM:
2015c609719bSwdenk		SDRAM timing
2016c609719bSwdenk
2017c609719bSwdenk- CFG_MAMR_PTA:
2018c609719bSwdenk		periodic timer for refresh
2019c609719bSwdenk
2020c609719bSwdenk- CFG_DER:	Debug Event Register (37-47)
2021c609719bSwdenk
2022c609719bSwdenk- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2023c609719bSwdenk  CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2024c609719bSwdenk  CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2025c609719bSwdenk  CFG_BR1_PRELIM:
2026c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2027c609719bSwdenk
2028c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2029c609719bSwdenk  CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2030c609719bSwdenk  CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2031c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2032c609719bSwdenk
2033c609719bSwdenk- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2034c609719bSwdenk  CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2035c609719bSwdenk		Machine Mode Register and Memory Periodic Timer
2036c609719bSwdenk		Prescaler definitions (SDRAM timing)
2037c609719bSwdenk
2038c609719bSwdenk- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2039c609719bSwdenk		enable I2C microcode relocation patch (MPC8xx);
2040c609719bSwdenk		define relocation offset in DPRAM [DSP2]
2041c609719bSwdenk
2042c609719bSwdenk- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2043c609719bSwdenk		enable SPI microcode relocation patch (MPC8xx);
2044c609719bSwdenk		define relocation offset in DPRAM [SCC4]
2045c609719bSwdenk
2046c609719bSwdenk- CFG_USE_OSCCLK:
2047c609719bSwdenk		Use OSCM clock mode on MBX8xx board. Be careful,
2048c609719bSwdenk		wrong setting might damage your board. Read
2049c609719bSwdenk		doc/README.MBX before setting this variable!
2050c609719bSwdenk
2051ea909b76Swdenk- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2052ea909b76Swdenk		Offset of the bootmode word in DPRAM used by post
2053ea909b76Swdenk		(Power On Self Tests). This definition overrides
2054ea909b76Swdenk		#define'd default value in commproc.h resp.
2055ea909b76Swdenk		cpm_8260.h.
2056ea909b76Swdenk
20575d232d0eSwdenk- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
20585d232d0eSwdenk  CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
20595d232d0eSwdenk  CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
20605d232d0eSwdenk  CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
20615d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
20625d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
20635d232d0eSwdenk  CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
20645d232d0eSwdenk  CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
20655d232d0eSwdenk		Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
20665d232d0eSwdenk
2067c26e454dSwdenk- CONFIG_ETHER_ON_FEC[12]
2068c26e454dSwdenk		Define to enable FEC[12] on a 8xx series processor.
2069c26e454dSwdenk
2070c26e454dSwdenk- CONFIG_FEC[12]_PHY
2071c26e454dSwdenk		Define to the hardcoded PHY address which corresponds
20726e592385Swdenk		to the given FEC; i. e.
2073c26e454dSwdenk			#define CONFIG_FEC1_PHY 4
2074c26e454dSwdenk		means that the PHY with address 4 is connected to FEC1
2075c26e454dSwdenk
2076c26e454dSwdenk		When set to -1, means to probe for first available.
2077c26e454dSwdenk
2078c26e454dSwdenk- CONFIG_FEC[12]_PHY_NORXERR
2079c26e454dSwdenk		The PHY does not have a RXERR line (RMII only).
2080c26e454dSwdenk		(so program the FEC to ignore it).
2081c26e454dSwdenk
2082c26e454dSwdenk- CONFIG_RMII
2083c26e454dSwdenk		Enable RMII mode for all FECs.
2084c26e454dSwdenk		Note that this is a global option, we can't
2085c26e454dSwdenk		have one FEC in standard MII mode and another in RMII mode.
2086c26e454dSwdenk
20875cf91d6bSwdenk- CONFIG_CRC32_VERIFY
20885cf91d6bSwdenk		Add a verify option to the crc32 command.
20895cf91d6bSwdenk		The syntax is:
20905cf91d6bSwdenk
20915cf91d6bSwdenk		=> crc32 -v <address> <count> <crc32>
20925cf91d6bSwdenk
20935cf91d6bSwdenk		Where address/count indicate a memory area
20945cf91d6bSwdenk		and crc32 is the correct crc32 which the
20955cf91d6bSwdenk		area should have.
20965cf91d6bSwdenk
209756523f12Swdenk- CONFIG_LOOPW
209856523f12Swdenk		Add the "loopw" memory command. This only takes effect if
209956523f12Swdenk		the memory commands are activated globally (CFG_CMD_MEM).
210056523f12Swdenk
2101c609719bSwdenkBuilding the Software:
2102c609719bSwdenk======================
2103c609719bSwdenk
2104c609719bSwdenkBuilding U-Boot has been tested in native PPC environments (on a
2105c609719bSwdenkPowerBook G3 running LinuxPPC 2000) and in cross environments
2106c609719bSwdenk(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2107c609719bSwdenkNetBSD 1.5 on x86).
2108c609719bSwdenk
2109c609719bSwdenkIf you are not using a native PPC environment, it is assumed that you
2110c609719bSwdenkhave the GNU cross compiling tools available in your path and named
2111c609719bSwdenkwith a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2112c609719bSwdenkyou are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2113c609719bSwdenkthe definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2114c609719bSwdenkchange it to:
2115c609719bSwdenk
2116c609719bSwdenk	CROSS_COMPILE = ppc_4xx-
2117c609719bSwdenk
2118c609719bSwdenk
2119c609719bSwdenkU-Boot is intended to be  simple  to  build.  After  installing	 the
2120c609719bSwdenksources	 you must configure U-Boot for one specific board type. This
2121c609719bSwdenkis done by typing:
2122c609719bSwdenk
2123c609719bSwdenk	make NAME_config
2124c609719bSwdenk
2125c609719bSwdenkwhere "NAME_config" is the name of one of the existing
2126c609719bSwdenkconfigurations; the following names are supported:
2127c609719bSwdenk
21281eaeb58eSwdenk	ADCIOP_config		FPS860L_config		omap730p2_config
21291eaeb58eSwdenk	ADS860_config		GEN860T_config		pcu_e_config
21301eaeb58eSwdenk	AR405_config		GENIETV_config		PIP405_config
21311eaeb58eSwdenk	at91rm9200dk_config	GTH_config		QS823_config
21321eaeb58eSwdenk	CANBT_config		hermes_config		QS850_config
21331eaeb58eSwdenk	cmi_mpc5xx_config	hymod_config		QS860T_config
21341eaeb58eSwdenk	cogent_common_config	IP860_config		RPXlite_config
2135e63c8ee3Swdenk	cogent_mpc8260_config	IVML24_config		RPXlite_DW_config
2136e63c8ee3Swdenk	cogent_mpc8xx_config	IVMS8_config		RPXsuper_config
2137e63c8ee3Swdenk	CPCI405_config		JSE_config		rsdproto_config
2138e63c8ee3Swdenk	CPCIISER4_config	LANTEC_config		Sandpoint8240_config
2139e63c8ee3Swdenk	csb272_config		lwmon_config		sbc8260_config
2140466b7410Swdenk	CU824_config		MBX860T_config		sbc8560_33_config
2141466b7410Swdenk	DUET_ADS_config		MBX_config		sbc8560_66_config
21428b07a110Swdenk	EBONY_config		MPC8260ADS_config	SM850_config
21438b07a110Swdenk	ELPT860_config		MPC8540ADS_config	SPD823TS_config
21448b07a110Swdenk	ESTEEM192E_config	MPC8560ADS_config	stxgp3_config
21458b07a110Swdenk	ETX094_config		NETVIA_config		SXNI855T_config
21468b07a110Swdenk	FADS823_config		omap1510inn_config	TQM823L_config
21478b07a110Swdenk	FADS850SAR_config	omap1610h2_config	TQM850L_config
21488b07a110Swdenk	FADS860T_config		omap1610inn_config	TQM855L_config
21498b07a110Swdenk	FPS850L_config		omap5912osk_config	TQM860L_config
21508b07a110Swdenk							WALNUT405_config
21518b07a110Swdenk							ZPC1900_config
215254387ac9Swdenk
2153c609719bSwdenkNote: for some board special configuration names may exist; check if
2154c609719bSwdenk      additional information is available from the board vendor; for
21552729af9dSwdenk      instance, the TQM823L systems are available without (standard)
21562729af9dSwdenk      or with LCD support. You can select such additional "features"
2157c609719bSwdenk      when chosing the configuration, i. e.
2158c609719bSwdenk
21592729af9dSwdenk      make TQM823L_config
21602729af9dSwdenk	- will configure for a plain TQM823L, i. e. no LCD support
2161c609719bSwdenk
2162c609719bSwdenk      make TQM823L_LCD_config
2163c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
2164c609719bSwdenk
2165c609719bSwdenk      etc.
2166c609719bSwdenk
2167c609719bSwdenk
2168c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
21697152b1d0Swdenkimages ready for download to / installation on your system:
2170c609719bSwdenk
2171c609719bSwdenk- "u-boot.bin" is a raw binary image
2172c609719bSwdenk- "u-boot" is an image in ELF binary format
2173c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
2174c609719bSwdenk
2175c609719bSwdenk
2176c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
2177c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
2178c609719bSwdenknative "make".
2179c609719bSwdenk
2180c609719bSwdenk
2181c609719bSwdenkIf the system board that you have is not listed, then you will need
2182c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
2183c609719bSwdenksteps:
2184c609719bSwdenk
2185c609719bSwdenk1.  Add a new configuration option for your board to the toplevel
218685ec0bccSwdenk    "Makefile" and to the "MAKEALL" script, using the existing
218785ec0bccSwdenk    entries as examples. Note that here and at many other places
21887152b1d0Swdenk    boards and other names are listed in alphabetical sort order. Please
218985ec0bccSwdenk    keep this order.
2190c609719bSwdenk2.  Create a new directory to hold your board specific code. Add any
219185ec0bccSwdenk    files you need. In your board directory, you will need at least
219285ec0bccSwdenk    the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
219385ec0bccSwdenk3.  Create a new configuration file "include/configs/<board>.h" for
219485ec0bccSwdenk    your board
2195c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
2196c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
219785ec0bccSwdenk4.  Run "make <board>_config" with your new name.
2198c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
2199c609719bSwdenk    to be installed on your target system.
220085ec0bccSwdenk6.  Debug and solve any problems that might arise.
2201c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
2202c609719bSwdenk
2203c609719bSwdenk
2204c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
2205c609719bSwdenk==============================================================
2206c609719bSwdenk
2207c609719bSwdenkIf you have modified U-Boot sources (for instance added a new	board
2208c609719bSwdenkor  support  for  new  devices,	 a new CPU, etc.) you are expected to
2209c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
2210c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
2211c609719bSwdenkofficial or latest in CVS) version of U-Boot sources.
2212c609719bSwdenk
2213c609719bSwdenkBut before you submit such a patch, please verify that	your  modifi-
2214c609719bSwdenkcation	did not break existing code. At least make sure that *ALL* of
2215c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
2216c609719bSwdenkjust run the "MAKEALL" script, which will configure and build U-Boot
2217c609719bSwdenkfor ALL supported system. Be warned, this will take a while. You  can
22187152b1d0Swdenkselect	which  (cross)	compiler  to use by passing a `CROSS_COMPILE'
2219c609719bSwdenkenvironment variable to the script, i. e. to use the cross tools from
2220c609719bSwdenkMontaVista's Hard Hat Linux you can type
2221c609719bSwdenk
2222c609719bSwdenk	CROSS_COMPILE=ppc_8xx- MAKEALL
2223c609719bSwdenk
2224c609719bSwdenkor to build on a native PowerPC system you can type
2225c609719bSwdenk
2226c609719bSwdenk	CROSS_COMPILE=' ' MAKEALL
2227c609719bSwdenk
2228c609719bSwdenkSee also "U-Boot Porting Guide" below.
2229c609719bSwdenk
2230c609719bSwdenk
2231c609719bSwdenkMonitor Commands - Overview:
2232c609719bSwdenk============================
2233c609719bSwdenk
2234c609719bSwdenkgo	- start application at address 'addr'
2235c609719bSwdenkrun	- run commands in an environment variable
2236c609719bSwdenkbootm	- boot application image from memory
2237c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
2238c609719bSwdenktftpboot- boot image via network using TFTP protocol
2239c609719bSwdenk	       and env variables "ipaddr" and "serverip"
2240c609719bSwdenk	       (and eventually "gatewayip")
2241c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
2242c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
2243c609719bSwdenkloads	- load S-Record file over serial line
2244c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
2245c609719bSwdenkmd	- memory display
2246c609719bSwdenkmm	- memory modify (auto-incrementing)
2247c609719bSwdenknm	- memory modify (constant address)
2248c609719bSwdenkmw	- memory write (fill)
2249c609719bSwdenkcp	- memory copy
2250c609719bSwdenkcmp	- memory compare
2251c609719bSwdenkcrc32	- checksum calculation
2252c609719bSwdenkimd	- i2c memory display
2253c609719bSwdenkimm	- i2c memory modify (auto-incrementing)
2254c609719bSwdenkinm	- i2c memory modify (constant address)
2255c609719bSwdenkimw	- i2c memory write (fill)
2256c609719bSwdenkicrc32	- i2c checksum calculation
2257c609719bSwdenkiprobe	- probe to discover valid I2C chip addresses
2258c609719bSwdenkiloop	- infinite loop on address range
2259c609719bSwdenkisdram	- print SDRAM configuration information
2260c609719bSwdenksspi	- SPI utility commands
2261c609719bSwdenkbase	- print or set address offset
2262c609719bSwdenkprintenv- print environment variables
2263c609719bSwdenksetenv	- set environment variables
2264c609719bSwdenksaveenv - save environment variables to persistent storage
2265c609719bSwdenkprotect - enable or disable FLASH write protection
2266c609719bSwdenkerase	- erase FLASH memory
2267c609719bSwdenkflinfo	- print FLASH memory information
2268c609719bSwdenkbdinfo	- print Board Info structure
2269c609719bSwdenkiminfo	- print header information for application image
2270c609719bSwdenkconinfo - print console devices and informations
2271c609719bSwdenkide	- IDE sub-system
2272c609719bSwdenkloop	- infinite loop on address range
227356523f12Swdenkloopw	- infinite write loop on address range
2274c609719bSwdenkmtest	- simple RAM test
2275c609719bSwdenkicache	- enable or disable instruction cache
2276c609719bSwdenkdcache	- enable or disable data cache
2277c609719bSwdenkreset	- Perform RESET of the CPU
2278c609719bSwdenkecho	- echo args to console
2279c609719bSwdenkversion - print monitor version
2280c609719bSwdenkhelp	- print online help
2281c609719bSwdenk?	- alias for 'help'
2282c609719bSwdenk
2283c609719bSwdenk
2284c609719bSwdenkMonitor Commands - Detailed Description:
2285c609719bSwdenk========================================
2286c609719bSwdenk
2287c609719bSwdenkTODO.
2288c609719bSwdenk
2289c609719bSwdenkFor now: just type "help <command>".
2290c609719bSwdenk
2291c609719bSwdenk
2292c609719bSwdenkEnvironment Variables:
2293c609719bSwdenk======================
2294c609719bSwdenk
2295c609719bSwdenkU-Boot supports user configuration using Environment Variables which
2296c609719bSwdenkcan be made persistent by saving to Flash memory.
2297c609719bSwdenk
2298c609719bSwdenkEnvironment Variables are set using "setenv", printed using
2299c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
2300c609719bSwdenkwithout a value can be used to delete a variable from the
2301c609719bSwdenkenvironment. As long as you don't save the environment you are
2302c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
2303c609719bSwdenkenvironment is erased by accident, a default environment is provided.
2304c609719bSwdenk
2305c609719bSwdenkSome configuration options can be set using Environment Variables:
2306c609719bSwdenk
2307c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
2308c609719bSwdenk
2309c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
2310c609719bSwdenk
2311c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
2312c609719bSwdenk
2313c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
2314c609719bSwdenk
2315c609719bSwdenk  bootfile	- Name of the image to load with TFTP
2316c609719bSwdenk
2317c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
2318c609719bSwdenk		  "bootp" will just load perform a lookup of the
2319c609719bSwdenk		  configuration from the BOOTP server, but not try to
2320c609719bSwdenk		  load any image using TFTP
2321c609719bSwdenk
2322c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
2323c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
2324c609719bSwdenk		  be automatically started (by internally calling
2325c609719bSwdenk		  "bootm")
2326c609719bSwdenk
23274a6fd34bSwdenk		  If set to "no", a standalone image passed to the
23284a6fd34bSwdenk		  "bootm" command will be copied to the load address
23294a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
23304a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
23314a6fd34bSwdenk		  data.
23324a6fd34bSwdenk
233317ea1177Swdenk  i2cfast	- (PPC405GP|PPC405EP only)
233417ea1177Swdenk		  if set to 'y' configures Linux I2C driver for fast
233517ea1177Swdenk		  mode (400kHZ). This environment variable is used in
233617ea1177Swdenk		  initialization code. So, for changes to be effective
233717ea1177Swdenk		  it must be saved and board must be reset.
233817ea1177Swdenk
2339c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
2340c609719bSwdenk		  If this variable is not set, initrd images will be
2341c609719bSwdenk		  copied to the highest possible address in RAM; this
2342c609719bSwdenk		  is usually what you want since it allows for
2343c609719bSwdenk		  maximum initrd size. If for some reason you want to
2344c609719bSwdenk		  make sure that the initrd image is loaded below the
2345c609719bSwdenk		  CFG_BOOTMAPSZ limit, you can set this environment
2346c609719bSwdenk		  variable to a value of "no" or "off" or "0".
2347c609719bSwdenk		  Alternatively, you can set it to a maximum upper
2348c609719bSwdenk		  address to use (U-Boot will still check that it
2349c609719bSwdenk		  does not overwrite the U-Boot stack and data).
2350c609719bSwdenk
2351c609719bSwdenk		  For instance, when you have a system with 16 MB
23527152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
2353c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
2354c609719bSwdenk		  the "bootargs" variable. However, now you must make
23557152b1d0Swdenk		  sure that the initrd image is placed in the first
2356c609719bSwdenk		  12 MB as well - this can be done with
2357c609719bSwdenk
2358c609719bSwdenk		  setenv initrd_high 00c00000
2359c609719bSwdenk
236038b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
236138b99261Swdenk		  indication to U-Boot that all addresses are legal
236238b99261Swdenk		  for the Linux kernel, including addresses in flash
236338b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
236438b99261Swdenk		  ramdisk at all. This may be useful to reduce the
236538b99261Swdenk		  boot time on your system, but requires that this
236638b99261Swdenk		  feature is supported by your Linux kernel.
236738b99261Swdenk
2368c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
2369c609719bSwdenk
2370c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
2371dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
2372c609719bSwdenk
2373c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
2374c609719bSwdenk
2375c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
2376c609719bSwdenk
2377c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
2378c609719bSwdenk
2379c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
2380c609719bSwdenk
2381c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
2382c609719bSwdenk
2383a3d991bdSwdenk  ethprime	- When CONFIG_NET_MULTI is enabled controls which
2384a3d991bdSwdenk		  interface is used first.
2385a3d991bdSwdenk
2386a3d991bdSwdenk  ethact	- When CONFIG_NET_MULTI is enabled controls which
2387a3d991bdSwdenk		  interface is currently active. For example you
2388a3d991bdSwdenk		  can do the following
2389a3d991bdSwdenk
2390a3d991bdSwdenk		  => setenv ethact FEC ETHERNET
2391a3d991bdSwdenk		  => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2392a3d991bdSwdenk		  => setenv ethact SCC ETHERNET
2393a3d991bdSwdenk		  => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2394a3d991bdSwdenk
2395a3d991bdSwdenk   netretry	- When set to "no" each network operation will
2396a3d991bdSwdenk		  either succeed or fail without retrying.
23976e592385Swdenk		  When set to "once" the network operation will
23986e592385Swdenk		  fail when all the available network interfaces
23996e592385Swdenk		  are tried once without success.
2400a3d991bdSwdenk		  Useful on scripts which control the retry operation
2401a3d991bdSwdenk		  themselves.
2402a3d991bdSwdenk
2403a3d991bdSwdenk   vlan		- When set to a value < 4095 the traffic over
2404a3d991bdSwdenk		  ethernet is encapsulated/received over 802.1q
2405a3d991bdSwdenk		  VLAN tagged frames.
2406c609719bSwdenk
2407c609719bSwdenkThe following environment variables may be used and automatically
2408c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
2409c609719bSwdenkdepending the information provided by your boot server:
2410c609719bSwdenk
2411c609719bSwdenk  bootfile	- see above
2412c609719bSwdenk  dnsip		- IP address of your Domain Name Server
2413fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
2414c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
2415c609719bSwdenk  hostname	- Target hostname
2416c609719bSwdenk  ipaddr	- see above
2417c609719bSwdenk  netmask	- Subnet Mask
2418c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
2419c609719bSwdenk  serverip	- see above
2420c609719bSwdenk
2421c609719bSwdenk
2422c609719bSwdenkThere are two special Environment Variables:
2423c609719bSwdenk
2424c609719bSwdenk  serial#	- contains hardware identification information such
2425c609719bSwdenk		  as type string and/or serial number
2426c609719bSwdenk  ethaddr	- Ethernet address
2427c609719bSwdenk
2428c609719bSwdenkThese variables can be set only once (usually during manufacturing of
2429c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
2430c609719bSwdenkonce they have been set once.
2431c609719bSwdenk
2432c609719bSwdenk
2433c1551ea8SstroeseFurther special Environment Variables:
2434c1551ea8Sstroese
2435c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
2436c1551ea8Sstroese		  with the "version" command. This variable is
2437c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
2438c1551ea8Sstroese
2439c1551ea8Sstroese
2440c609719bSwdenkPlease note that changes to some configuration parameters may take
2441c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
2442c609719bSwdenk
2443c609719bSwdenk
2444f07771ccSwdenkCommand Line Parsing:
2445f07771ccSwdenk=====================
2446f07771ccSwdenk
2447f07771ccSwdenkThere are two different command line parsers available with U-Boot:
24487152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
2449f07771ccSwdenk
2450f07771ccSwdenkOld, simple command line parser:
2451f07771ccSwdenk--------------------------------
2452f07771ccSwdenk
2453f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
2454f07771ccSwdenk- several commands on one line, separated by ';'
2455f07771ccSwdenk- variable substitution using "... $(name) ..." syntax
2456f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
2457f07771ccSwdenk  for example:
2458f07771ccSwdenk	setenv bootcmd bootm \$(address)
2459f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
2460f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2461f07771ccSwdenk
2462f07771ccSwdenkHush shell:
2463f07771ccSwdenk-----------
2464f07771ccSwdenk
2465f07771ccSwdenk- similar to Bourne shell, with control structures like
2466f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
2467f07771ccSwdenk  until...do...done, ...
2468f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
2469f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
2470f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
2471f07771ccSwdenk  command
2472f07771ccSwdenk
2473f07771ccSwdenkGeneral rules:
2474f07771ccSwdenk--------------
2475f07771ccSwdenk
2476f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
2477f07771ccSwdenk    command) contains several commands separated by semicolon, and
2478f07771ccSwdenk    one of these commands fails, then the remaining commands will be
2479f07771ccSwdenk    executed anyway.
2480f07771ccSwdenk
2481f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
2482f07771ccSwdenk    calling run with a list af variables as arguments), any failing
2483f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
2484f07771ccSwdenk    variables are not executed.
2485f07771ccSwdenk
2486c609719bSwdenkNote for Redundant Ethernet Interfaces:
2487c609719bSwdenk=======================================
2488c609719bSwdenk
24897152b1d0SwdenkSome boards come with redundant ethernet interfaces; U-Boot supports
2490c609719bSwdenksuch configurations and is capable of automatic selection of a
24917152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
2492c609719bSwdenk
2493c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
2494c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2495c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
2496c609719bSwdenk
2497c609719bSwdenkIf the network interface stores some valid MAC address (for instance
2498c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
2499c609719bSwdenkding setting in the environment; if the corresponding environment
2500c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
2501c609719bSwdenk
2502c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
2503c609719bSwdenk  environment, the SROM's address is used.
2504c609719bSwdenk
2505c609719bSwdenko If there is no valid address in the SROM, and a definition in the
2506c609719bSwdenk  environment exists, then the value from the environment variable is
2507c609719bSwdenk  used.
2508c609719bSwdenk
2509c609719bSwdenko If both the SROM and the environment contain a MAC address, and
2510c609719bSwdenk  both addresses are the same, this MAC address is used.
2511c609719bSwdenk
2512c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
2513c609719bSwdenk  addresses differ, the value from the environment is used and a
2514c609719bSwdenk  warning is printed.
2515c609719bSwdenk
2516c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
2517c609719bSwdenk  is raised.
2518c609719bSwdenk
2519c609719bSwdenk
2520c609719bSwdenkImage Formats:
2521c609719bSwdenk==============
2522c609719bSwdenk
2523c609719bSwdenkThe "boot" commands of this monitor operate on "image" files which
2524c609719bSwdenkcan be basicly anything, preceeded by a special header; see the
2525c609719bSwdenkdefinitions in include/image.h for details; basicly, the header
2526c609719bSwdenkdefines the following image properties:
2527c609719bSwdenk
2528c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2529c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
25307f70e853Swdenk  LynxOS, pSOS, QNX, RTEMS, ARTOS;
25311f4bb37dSwdenk  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2532c609719bSwdenk* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
25333d1e8a9dSwdenk  IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
25343d1e8a9dSwdenk  Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2535c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
2536c609719bSwdenk* Load Address
2537c609719bSwdenk* Entry Point
2538c609719bSwdenk* Image Name
2539c609719bSwdenk* Image Timestamp
2540c609719bSwdenk
2541c609719bSwdenkThe header is marked by a special Magic Number, and both the header
2542c609719bSwdenkand the data portions of the image are secured against corruption by
2543c609719bSwdenkCRC32 checksums.
2544c609719bSwdenk
2545c609719bSwdenk
2546c609719bSwdenkLinux Support:
2547c609719bSwdenk==============
2548c609719bSwdenk
2549c609719bSwdenkAlthough U-Boot should support any OS or standalone application
25507152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
2551c609719bSwdenkU-Boot.
2552c609719bSwdenk
2553c609719bSwdenkU-Boot includes many features that so far have been part of some
2554c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
2555c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
2556c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
25577152b1d0Swdenkserves several purposes:
2558c609719bSwdenk
2559c609719bSwdenk- the same features can be used for other OS or standalone
2560c609719bSwdenk  applications (for instance: using compressed images to reduce the
2561c609719bSwdenk  Flash memory footprint)
2562c609719bSwdenk
2563c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
25647152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
2565c609719bSwdenk
2566c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
2567c609719bSwdenk  images; of course this also means that different kernel images can
2568c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
2569c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
2570c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
2571c609719bSwdenk  software is easier now.
2572c609719bSwdenk
2573c609719bSwdenk
2574c609719bSwdenkLinux HOWTO:
2575c609719bSwdenk============
2576c609719bSwdenk
2577c609719bSwdenkPorting Linux to U-Boot based systems:
2578c609719bSwdenk---------------------------------------
2579c609719bSwdenk
2580c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
2581c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
2582c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
2583c609719bSwdenkLinux :-).
2584c609719bSwdenk
2585c609719bSwdenkBut now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2586c609719bSwdenk
2587c609719bSwdenkJust make sure your machine specific header file (for instance
2588c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
2589c609719bSwdenkInformation structure as we define in include/u-boot.h, and make
2590c609719bSwdenksure that your definition of IMAP_ADDR uses the same value as your
2591c609719bSwdenkU-Boot configuration in CFG_IMMR.
2592c609719bSwdenk
2593c609719bSwdenk
2594c609719bSwdenkConfiguring the Linux kernel:
2595c609719bSwdenk-----------------------------
2596c609719bSwdenk
2597c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
2598c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
2599c609719bSwdenk
2600c609719bSwdenk
2601c609719bSwdenkBuilding a Linux Image:
2602c609719bSwdenk-----------------------
2603c609719bSwdenk
260424ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
260524ee89b9Swdenknot used. If you use recent kernel source, a new build target
260624ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
260724ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
260824ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
260924ee89b9Swdenk100% compatible format.
2610c609719bSwdenk
2611c609719bSwdenkExample:
2612c609719bSwdenk
2613c609719bSwdenk	make TQM850L_config
2614c609719bSwdenk	make oldconfig
2615c609719bSwdenk	make dep
261624ee89b9Swdenk	make uImage
2617c609719bSwdenk
261824ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
261924ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
262024ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
2621c609719bSwdenk
262224ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
262324ee89b9Swdenk
262424ee89b9Swdenk* convert the kernel into a raw binary image:
262524ee89b9Swdenk
262624ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
262724ee89b9Swdenk				 -R .note -R .comment \
262824ee89b9Swdenk				 -S vmlinux linux.bin
262924ee89b9Swdenk
263024ee89b9Swdenk* compress the binary image:
263124ee89b9Swdenk
263224ee89b9Swdenk	gzip -9 linux.bin
263324ee89b9Swdenk
263424ee89b9Swdenk* package compressed binary image for U-Boot:
263524ee89b9Swdenk
263624ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
263724ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
263824ee89b9Swdenk		-d linux.bin.gz uImage
263924ee89b9Swdenk
264024ee89b9Swdenk
264124ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
264224ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
264324ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
264424ee89b9Swdenkbyte header containing information about target architecture,
264524ee89b9Swdenkoperating system, image type, compression method, entry points, time
264624ee89b9Swdenkstamp, CRC32 checksums, etc.
264724ee89b9Swdenk
264824ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
264924ee89b9Swdenkprint the header information, or to build new images.
2650c609719bSwdenk
2651c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
2652c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
2653c609719bSwdenkchecksum verification:
2654c609719bSwdenk
2655c609719bSwdenk	tools/mkimage -l image
2656c609719bSwdenk	  -l ==> list image header information
2657c609719bSwdenk
2658c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
2659c609719bSwdenkfrom a "data file" which is used as image payload:
2660c609719bSwdenk
2661c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2662c609719bSwdenk		      -n name -d data_file image
2663c609719bSwdenk	  -A ==> set architecture to 'arch'
2664c609719bSwdenk	  -O ==> set operating system to 'os'
2665c609719bSwdenk	  -T ==> set image type to 'type'
2666c609719bSwdenk	  -C ==> set compression type 'comp'
2667c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
2668c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
2669c609719bSwdenk	  -n ==> set image name to 'name'
2670c609719bSwdenk	  -d ==> use image data from 'datafile'
2671c609719bSwdenk
267269459791SwdenkRight now, all Linux kernels for PowerPC systems use the same load
267369459791Swdenkaddress (0x00000000), but the entry point address depends on the
267469459791Swdenkkernel version:
2675c609719bSwdenk
2676c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
267724ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
2678c609719bSwdenk
2679c609719bSwdenkSo a typical call to build a U-Boot image would read:
2680c609719bSwdenk
268124ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
268224ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
268324ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
268424ee89b9Swdenk	> examples/uImage.TQM850L
268524ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2686c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2687c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
2688c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
2689c609719bSwdenk	Load Address: 0x00000000
269024ee89b9Swdenk	Entry Point:  0x00000000
2691c609719bSwdenk
2692c609719bSwdenkTo verify the contents of the image (or check for corruption):
2693c609719bSwdenk
269424ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
269524ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2696c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2697c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
2698c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
2699c609719bSwdenk	Load Address: 0x00000000
270024ee89b9Swdenk	Entry Point:  0x00000000
2701c609719bSwdenk
2702c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
2703c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
2704c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
2705c609719bSwdenkneed to be uncompressed:
2706c609719bSwdenk
270724ee89b9Swdenk	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
270824ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
270924ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
271024ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
271124ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
271224ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
2713c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
2714c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
2715c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
2716c609719bSwdenk	Load Address: 0x00000000
271724ee89b9Swdenk	Entry Point:  0x00000000
2718c609719bSwdenk
2719c609719bSwdenk
2720c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
2721c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
2722c609719bSwdenk
2723c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
2724c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
2725c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2726c609719bSwdenk	Image Name:   Simple Ramdisk Image
2727c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
2728c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
2729c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
2730c609719bSwdenk	Load Address: 0x00000000
2731c609719bSwdenk	Entry Point:  0x00000000
2732c609719bSwdenk
2733c609719bSwdenk
2734c609719bSwdenkInstalling a Linux Image:
2735c609719bSwdenk-------------------------
2736c609719bSwdenk
2737c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
2738c609719bSwdenkyou must convert the image to S-Record format:
2739c609719bSwdenk
2740c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
2741c609719bSwdenk
2742c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
2743c609719bSwdenkimage header, so the resulting S-Record file will be relative to
2744c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
2745c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
2746c609719bSwdenkcommand.
2747c609719bSwdenk
2748c609719bSwdenkExample: install the image to address 0x40100000 (which on the
2749c609719bSwdenkTQM8xxL is in the first Flash bank):
2750c609719bSwdenk
2751c609719bSwdenk	=> erase 40100000 401FFFFF
2752c609719bSwdenk
2753c609719bSwdenk	.......... done
2754c609719bSwdenk	Erased 8 sectors
2755c609719bSwdenk
2756c609719bSwdenk	=> loads 40100000
2757c609719bSwdenk	## Ready for S-Record download ...
2758c609719bSwdenk	~>examples/image.srec
2759c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2760c609719bSwdenk	...
2761c609719bSwdenk	15989 15990 15991 15992
2762c609719bSwdenk	[file transfer complete]
2763c609719bSwdenk	[connected]
2764c609719bSwdenk	## Start Addr = 0x00000000
2765c609719bSwdenk
2766c609719bSwdenk
2767c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
2768c609719bSwdenkthis includes a checksum verification so you  can  be  sure  no	 data
2769c609719bSwdenkcorruption happened:
2770c609719bSwdenk
2771c609719bSwdenk	=> imi 40100000
2772c609719bSwdenk
2773c609719bSwdenk	## Checking Image at 40100000 ...
2774c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2775c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2776c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2777c609719bSwdenk	   Load Address: 00000000
2778c609719bSwdenk	   Entry Point:	 0000000c
2779c609719bSwdenk	   Verifying Checksum ... OK
2780c609719bSwdenk
2781c609719bSwdenk
2782c609719bSwdenkBoot Linux:
2783c609719bSwdenk-----------
2784c609719bSwdenk
2785c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
2786c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
2787c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
2788c609719bSwdenkparameters. You can check and modify this variable using the
2789c609719bSwdenk"printenv" and "setenv" commands:
2790c609719bSwdenk
2791c609719bSwdenk
2792c609719bSwdenk	=> printenv bootargs
2793c609719bSwdenk	bootargs=root=/dev/ram
2794c609719bSwdenk
2795c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2796c609719bSwdenk
2797c609719bSwdenk	=> printenv bootargs
2798c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2799c609719bSwdenk
2800c609719bSwdenk	=> bootm 40020000
2801c609719bSwdenk	## Booting Linux kernel at 40020000 ...
2802c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
2803c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2804c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
2805c609719bSwdenk	   Load Address: 00000000
2806c609719bSwdenk	   Entry Point:	 0000000c
2807c609719bSwdenk	   Verifying Checksum ... OK
2808c609719bSwdenk	   Uncompressing Kernel Image ... OK
2809c609719bSwdenk	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
2810c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2811c609719bSwdenk	time_init: decrementer frequency = 187500000/60
2812c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
2813c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2814c609719bSwdenk	...
2815c609719bSwdenk
2816c609719bSwdenkIf you want to boot a Linux kernel with initial ram disk, you pass
28177152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
2818c609719bSwdenkformat!) to the "bootm" command:
2819c609719bSwdenk
2820c609719bSwdenk	=> imi 40100000 40200000
2821c609719bSwdenk
2822c609719bSwdenk	## Checking Image at 40100000 ...
2823c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2824c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2825c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2826c609719bSwdenk	   Load Address: 00000000
2827c609719bSwdenk	   Entry Point:	 0000000c
2828c609719bSwdenk	   Verifying Checksum ... OK
2829c609719bSwdenk
2830c609719bSwdenk	## Checking Image at 40200000 ...
2831c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
2832c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
2833c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
2834c609719bSwdenk	   Load Address: 00000000
2835c609719bSwdenk	   Entry Point:	 00000000
2836c609719bSwdenk	   Verifying Checksum ... OK
2837c609719bSwdenk
2838c609719bSwdenk	=> bootm 40100000 40200000
2839c609719bSwdenk	## Booting Linux kernel at 40100000 ...
2840c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
2841c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
2842c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
2843c609719bSwdenk	   Load Address: 00000000
2844c609719bSwdenk	   Entry Point:	 0000000c
2845c609719bSwdenk	   Verifying Checksum ... OK
2846c609719bSwdenk	   Uncompressing Kernel Image ... OK
2847c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
2848c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
2849c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
2850c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
2851c609719bSwdenk	   Load Address: 00000000
2852c609719bSwdenk	   Entry Point:	 00000000
2853c609719bSwdenk	   Verifying Checksum ... OK
2854c609719bSwdenk	   Loading Ramdisk ... OK
2855c609719bSwdenk	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
2856c609719bSwdenk	Boot arguments: root=/dev/ram
2857c609719bSwdenk	time_init: decrementer frequency = 187500000/60
2858c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
2859c609719bSwdenk	...
2860c609719bSwdenk	RAMDISK: Compressed image found at block 0
2861c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
2862c609719bSwdenk
2863c609719bSwdenk	bash#
2864c609719bSwdenk
28656069ff26SwdenkMore About U-Boot Image Types:
28666069ff26Swdenk------------------------------
28676069ff26Swdenk
28686069ff26SwdenkU-Boot supports the following image types:
28696069ff26Swdenk
28706069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
28716069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
28726069ff26Swdenk	well) you can continue to work in U-Boot after return from
28736069ff26Swdenk	the Standalone Program.
28746069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
28756069ff26Swdenk	will take over control completely. Usually these programs
28766069ff26Swdenk	will install their own set of exception handlers, device
28776069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
28786069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
28796069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
28806069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
28816069ff26Swdenk	being started.
28826069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
28836069ff26Swdenk	(Linux) kernel image and one or more data images like
28846069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
28856069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
28866069ff26Swdenk	server provides just a single image file, but you want to get
28876069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
28886069ff26Swdenk
28896069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
28906069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
28916069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
28926069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
28936069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
28946069ff26Swdenk	a multiple of 4 bytes).
28956069ff26Swdenk
28966069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
28976069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
28986069ff26Swdenk	flash memory.
28996069ff26Swdenk
29006069ff26Swdenk   "Script files" are command sequences that will be executed by
29016069ff26Swdenk	U-Boot's command interpreter; this feature is especially
29026069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
29036069ff26Swdenk	as command interpreter.
29046069ff26Swdenk
2905c609719bSwdenk
2906c609719bSwdenkStandalone HOWTO:
2907c609719bSwdenk=================
2908c609719bSwdenk
2909c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
2910c609719bSwdenkrun "standalone" applications, which can use some resources of
2911c609719bSwdenkU-Boot like console I/O functions or interrupt services.
2912c609719bSwdenk
2913c609719bSwdenkTwo simple examples are included with the sources:
2914c609719bSwdenk
2915c609719bSwdenk"Hello World" Demo:
2916c609719bSwdenk-------------------
2917c609719bSwdenk
2918c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
2919c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
2920c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
2921c609719bSwdenklike that:
2922c609719bSwdenk
2923c609719bSwdenk	=> loads
2924c609719bSwdenk	## Ready for S-Record download ...
2925c609719bSwdenk	~>examples/hello_world.srec
2926c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
2927c609719bSwdenk	[file transfer complete]
2928c609719bSwdenk	[connected]
2929c609719bSwdenk	## Start Addr = 0x00040004
2930c609719bSwdenk
2931c609719bSwdenk	=> go 40004 Hello World! This is a test.
2932c609719bSwdenk	## Starting application at 0x00040004 ...
2933c609719bSwdenk	Hello World
2934c609719bSwdenk	argc = 7
2935c609719bSwdenk	argv[0] = "40004"
2936c609719bSwdenk	argv[1] = "Hello"
2937c609719bSwdenk	argv[2] = "World!"
2938c609719bSwdenk	argv[3] = "This"
2939c609719bSwdenk	argv[4] = "is"
2940c609719bSwdenk	argv[5] = "a"
2941c609719bSwdenk	argv[6] = "test."
2942c609719bSwdenk	argv[7] = "<NULL>"
2943c609719bSwdenk	Hit any key to exit ...
2944c609719bSwdenk
2945c609719bSwdenk	## Application terminated, rc = 0x0
2946c609719bSwdenk
2947c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
2948c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
2949c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
2950c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
2951c609719bSwdenkcharacter, but this is just a demo program. The application can be
2952c609719bSwdenkcontrolled by the following keys:
2953c609719bSwdenk
2954c609719bSwdenk	? - print current values og the CPM Timer registers
2955c609719bSwdenk	b - enable interrupts and start timer
2956c609719bSwdenk	e - stop timer and disable interrupts
2957c609719bSwdenk	q - quit application
2958c609719bSwdenk
2959c609719bSwdenk	=> loads
2960c609719bSwdenk	## Ready for S-Record download ...
2961c609719bSwdenk	~>examples/timer.srec
2962c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
2963c609719bSwdenk	[file transfer complete]
2964c609719bSwdenk	[connected]
2965c609719bSwdenk	## Start Addr = 0x00040004
2966c609719bSwdenk
2967c609719bSwdenk	=> go 40004
2968c609719bSwdenk	## Starting application at 0x00040004 ...
2969c609719bSwdenk	TIMERS=0xfff00980
2970c609719bSwdenk	Using timer 1
2971c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2972c609719bSwdenk
2973c609719bSwdenkHit 'b':
2974c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
2975c609719bSwdenk	Enabling timer
2976c609719bSwdenkHit '?':
2977c609719bSwdenk	[q, b, e, ?] ........
2978c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2979c609719bSwdenkHit '?':
2980c609719bSwdenk	[q, b, e, ?] .
2981c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2982c609719bSwdenkHit '?':
2983c609719bSwdenk	[q, b, e, ?] .
2984c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2985c609719bSwdenkHit '?':
2986c609719bSwdenk	[q, b, e, ?] .
2987c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2988c609719bSwdenkHit 'e':
2989c609719bSwdenk	[q, b, e, ?] ...Stopping timer
2990c609719bSwdenkHit 'q':
2991c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
2992c609719bSwdenk
2993c609719bSwdenk
299485ec0bccSwdenkMinicom warning:
299585ec0bccSwdenk================
299685ec0bccSwdenk
29977152b1d0SwdenkOver time, many people have reported problems when trying to use the
299885ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
299985ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
3000f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
300185ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
300285ec0bccSwdenkuse "cu" for S-Record download ("loads" command).
300385ec0bccSwdenk
300452f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
300552f52c14Swdenkconfiguration to your "File transfer protocols" section:
300652f52c14Swdenk
300752f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
300852f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
300952f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
301052f52c14Swdenk
301152f52c14Swdenk
3012c609719bSwdenkNetBSD Notes:
3013c609719bSwdenk=============
3014c609719bSwdenk
3015c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
3016c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
3017c609719bSwdenk
3018c609719bSwdenkBuilding requires a cross environment; it is known to work on
3019c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3020c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
3021c609719bSwdenkNote that the cross-powerpc package does not install include files;
3022c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
3023c609719bSwdenkmissing.  This file has to be installed and patched manually:
3024c609719bSwdenk
3025c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
3026c609719bSwdenk	# mkdir powerpc
3027c609719bSwdenk	# ln -s powerpc machine
3028c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3029c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
3030c609719bSwdenk
3031c609719bSwdenkNative builds *don't* work due to incompatibilities between native
3032c609719bSwdenkand U-Boot include files.
3033c609719bSwdenk
3034c609719bSwdenkBooting assumes that (the first part of) the image booted is a
3035c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
3036c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
3037c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3038c609719bSwdenkmeantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
3039c609719bSwdenkdetails.
3040c609719bSwdenk
3041c609719bSwdenk
3042c609719bSwdenkImplementation Internals:
3043c609719bSwdenk=========================
3044c609719bSwdenk
3045c609719bSwdenkThe following is not intended to be a complete description of every
3046c609719bSwdenkimplementation detail. However, it should help to understand the
3047c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
3048c609719bSwdenkhardware.
3049c609719bSwdenk
3050c609719bSwdenk
3051c609719bSwdenkInitial Stack, Global Data:
3052c609719bSwdenk---------------------------
3053c609719bSwdenk
3054c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
3055c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
3056c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
3057c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
3058c609719bSwdenkis not initialized as zero. To be able to get a C environment working
3059c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
3060c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
3061c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
3062c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
3063c609719bSwdenklocked as (mis-) used as memory, etc.
3064c609719bSwdenk
30657152b1d0Swdenk	Chris Hallinan posted a good summary of	 these	issues	to  the
306643d9616cSwdenk	u-boot-users mailing list:
306743d9616cSwdenk
306843d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
306943d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
307043d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
307143d9616cSwdenk	...
307243d9616cSwdenk
307343d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
307443d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
307543d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
307643d9616cSwdenk	is that the cache is being used as a temporary supply of
307743d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
307843d9616cSwdenk	beyond the scope of this list to expain the details, but you
307943d9616cSwdenk	can see how this works by studying the cache architecture and
308043d9616cSwdenk	operation in the architecture and processor-specific manuals.
308143d9616cSwdenk
308243d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
308343d9616cSwdenk	is another option for the system designer to use as an
308443d9616cSwdenk	initial stack/ram area prior to SDRAM being available. Either
308543d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
308643d9616cSwdenk	board designers haven't used it for something that would
308743d9616cSwdenk	cause you grief during the initial boot! It is frequently not
308843d9616cSwdenk	used.
308943d9616cSwdenk
309043d9616cSwdenk	CFG_INIT_RAM_ADDR should be somewhere that won't interfere
309143d9616cSwdenk	with your processor/board/system design. The default value
309243d9616cSwdenk	you will find in any recent u-boot distribution in
309343d9616cSwdenk	Walnut405.h should work for you. I'd set it to a value larger
309443d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
309543d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
309643d9616cSwdenk	that are supposed to respond to that address! That code in
309743d9616cSwdenk	start.S has been around a while and should work as is when
309843d9616cSwdenk	you get the config right.
309943d9616cSwdenk
310043d9616cSwdenk	-Chris Hallinan
310143d9616cSwdenk	DS4.COM, Inc.
310243d9616cSwdenk
3103c609719bSwdenkIt is essential to remember this, since it has some impact on the C
3104c609719bSwdenkcode for the initialization procedures:
3105c609719bSwdenk
3106c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
3107c609719bSwdenk  to write it.
3108c609719bSwdenk
3109c609719bSwdenk* Do not use any unitialized global data (or implicitely initialized
3110c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
31117152b1d0Swdenk  zation is performed later (when relocating to RAM).
3112c609719bSwdenk
3113c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
3114c609719bSwdenk  that.
3115c609719bSwdenk
3116c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
3117c609719bSwdenknormal global data to share information beween the code. But it
3118c609719bSwdenkturned out that the implementation of U-Boot can be greatly
3119c609719bSwdenksimplified by making a global data structure (gd_t) available to all
3120c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
3121c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
3122c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
3123c609719bSwdenkplace a pointer (gd) to the global data into a register which we
3124c609719bSwdenkreserve for this purpose.
3125c609719bSwdenk
31267152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
3127c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
3128c609719bSwdenkGCC's implementation.
3129c609719bSwdenk
3130c609719bSwdenkFor PowerPC, the following registers have specific use:
3131c609719bSwdenk	R1:	stack pointer
3132c609719bSwdenk	R2:	TOC pointer
3133c609719bSwdenk	R3-R4:	parameter passing and return values
3134c609719bSwdenk	R5-R10: parameter passing
3135c609719bSwdenk	R13:	small data area pointer
3136c609719bSwdenk	R30:	GOT pointer
3137c609719bSwdenk	R31:	frame pointer
3138c609719bSwdenk
3139c609719bSwdenk	(U-Boot also uses R14 as internal GOT pointer.)
3140c609719bSwdenk
3141c609719bSwdenk    ==> U-Boot will use R29 to hold a pointer to the global data
3142c609719bSwdenk
3143c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
3144c609719bSwdenk    address of the global data structure is known at compile time),
3145c609719bSwdenk    but it turned out that reserving a register results in somewhat
3146c609719bSwdenk    smaller code - although the code savings are not that big (on
3147c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
3148c609719bSwdenk    624 text + 127 data).
3149c609719bSwdenk
3150c609719bSwdenkOn ARM, the following registers are used:
3151c609719bSwdenk
3152c609719bSwdenk	R0:	function argument word/integer result
3153c609719bSwdenk	R1-R3:	function argument word
3154c609719bSwdenk	R9:	GOT pointer
3155c609719bSwdenk	R10:	stack limit (used only if stack checking if enabled)
3156c609719bSwdenk	R11:	argument (frame) pointer
3157c609719bSwdenk	R12:	temporary workspace
3158c609719bSwdenk	R13:	stack pointer
3159c609719bSwdenk	R14:	link register
3160c609719bSwdenk	R15:	program counter
3161c609719bSwdenk
3162c609719bSwdenk    ==> U-Boot will use R8 to hold a pointer to the global data
3163c609719bSwdenk
3164c609719bSwdenk
3165c609719bSwdenkMemory Management:
3166c609719bSwdenk------------------
3167c609719bSwdenk
3168c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
3169c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
3170c609719bSwdenk
3171c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
3172c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
3173c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
3174c609719bSwdenkphysical memory banks.
3175c609719bSwdenk
3176c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
3177c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3178c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
3179c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
3180c609719bSwdenkmemory is reserved for use by malloc() [see CFG_MALLOC_LEN
3181c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
3182c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
3183c609719bSwdenk
3184c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
3185c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
3186c609719bSwdenk
3187c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
3188c609719bSwdenkthis:
3189c609719bSwdenk
3190c609719bSwdenk	0x0000 0000	Exception Vector code
3191c609719bSwdenk	      :
3192c609719bSwdenk	0x0000 1FFF
3193c609719bSwdenk	0x0000 2000	Free for Application Use
3194c609719bSwdenk	      :
3195c609719bSwdenk	      :
3196c609719bSwdenk
3197c609719bSwdenk	      :
3198c609719bSwdenk	      :
3199c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
3200c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
3201c609719bSwdenk	0x00FC 0000	Malloc Arena
3202c609719bSwdenk	      :
3203c609719bSwdenk	0x00FD FFFF
3204c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
3205c609719bSwdenk	...		eventually: LCD or video framebuffer
3206c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
3207c609719bSwdenk	0x00FF FFFF	[End of RAM]
3208c609719bSwdenk
3209c609719bSwdenk
3210c609719bSwdenkSystem Initialization:
3211c609719bSwdenk----------------------
3212c609719bSwdenk
3213c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
3214c609719bSwdenk(on most PowerPC systens at address 0x00000100). Because of the reset
3215c609719bSwdenkconfiguration for CS0# this is a mirror of the onboard Flash memory.
32167152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
3217c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
3218c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
3219c609719bSwdenkwhich provide such a feature like MPC8xx or MPC8260), or in a locked
3220c609719bSwdenkpart of the data cache. After that, U-Boot initializes the CPU core,
3221c609719bSwdenkthe caches and the SIU.
3222c609719bSwdenk
3223c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
3224c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
3225c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3226c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3227c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
3228c609719bSwdenksimple memory test is run that determines the size of the SDRAM
3229c609719bSwdenkbanks.
3230c609719bSwdenk
3231c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
32327152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
3233c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
3234c609719bSwdenk0x00000000, with any additional banks following immediately to create
3235c609719bSwdenkcontiguous memory starting from 0.
3236c609719bSwdenk
3237c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
3238c609719bSwdenkand allocates memory for use by malloc() and for the global Board
3239c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
3240c609719bSwdenkpages, and the final stack is set up.
3241c609719bSwdenk
3242c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
3243c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
3244c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
3245c609719bSwdenknew address in RAM.
3246c609719bSwdenk
3247c609719bSwdenk
3248c609719bSwdenkU-Boot Porting Guide:
3249c609719bSwdenk----------------------
3250c609719bSwdenk
3251c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
32526aff3115Swdenklist, October 2002]
3253c609719bSwdenk
3254c609719bSwdenk
3255c609719bSwdenkint main (int argc, char *argv[])
3256c609719bSwdenk{
3257c609719bSwdenk	sighandler_t no_more_time;
3258c609719bSwdenk
3259c609719bSwdenk	signal (SIGALRM, no_more_time);
3260c609719bSwdenk	alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3261c609719bSwdenk
3262c609719bSwdenk	if (available_money > available_manpower) {
3263c609719bSwdenk		pay consultant to port U-Boot;
3264c609719bSwdenk		return 0;
3265c609719bSwdenk	}
3266c609719bSwdenk
3267c609719bSwdenk	Download latest U-Boot source;
3268c609719bSwdenk
32696aff3115Swdenk	Subscribe to u-boot-users mailing list;
32706aff3115Swdenk
3271c609719bSwdenk	if (clueless) {
3272c609719bSwdenk		email ("Hi, I am new to U-Boot, how do I get started?");
3273c609719bSwdenk	}
3274c609719bSwdenk
3275c609719bSwdenk	while (learning) {
3276c609719bSwdenk		Read the README file in the top level directory;
32777cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3278c609719bSwdenk		Read the source, Luke;
3279c609719bSwdenk	}
3280c609719bSwdenk
3281c609719bSwdenk	if (available_money > toLocalCurrency ($2500)) {
3282c609719bSwdenk		Buy a BDI2000;
3283c609719bSwdenk	} else {
3284c609719bSwdenk		Add a lot of aggravation and time;
3285c609719bSwdenk	}
3286c609719bSwdenk
3287c609719bSwdenk	Create your own board support subdirectory;
3288c609719bSwdenk
32896aff3115Swdenk	Create your own board config file;
32906aff3115Swdenk
3291c609719bSwdenk	while (!running) {
3292c609719bSwdenk		do {
3293c609719bSwdenk			Add / modify source code;
3294c609719bSwdenk		} until (compiles);
3295c609719bSwdenk		Debug;
3296c609719bSwdenk		if (clueless)
3297c609719bSwdenk			email ("Hi, I am having problems...");
3298c609719bSwdenk	}
3299c609719bSwdenk	Send patch file to Wolfgang;
3300c609719bSwdenk
3301c609719bSwdenk	return 0;
3302c609719bSwdenk}
3303c609719bSwdenk
3304c609719bSwdenkvoid no_more_time (int sig)
3305c609719bSwdenk{
3306c609719bSwdenk      hire_a_guru();
3307c609719bSwdenk}
3308c609719bSwdenk
3309c609719bSwdenk
3310c609719bSwdenkCoding Standards:
3311c609719bSwdenk-----------------
3312c609719bSwdenk
3313c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
3314c609719bSwdenkcoding style; see the file "Documentation/CodingStyle" in your Linux
3315c609719bSwdenkkernel source directory.
3316c609719bSwdenk
3317c609719bSwdenkPlease note that U-Boot is implemented in C (and to some small parts
3318c609719bSwdenkin Assembler); no C++ is used, so please do not use C++ style
3319c609719bSwdenkcomments (//) in your code.
3320c609719bSwdenk
3321c178d3daSwdenkPlease also stick to the following formatting rules:
3322180d3f74Swdenk- remove any trailing white space
3323180d3f74Swdenk- use TAB characters for indentation, not spaces
3324180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
3325180d3f74Swdenk- do not add more than 2 empty lines to source files
3326180d3f74Swdenk- do not add trailing empty lines to source files
3327180d3f74Swdenk
3328c609719bSwdenkSubmissions which do not conform to the standards may be returned
3329c609719bSwdenkwith a request to reformat the changes.
3330c609719bSwdenk
3331c609719bSwdenk
3332c609719bSwdenkSubmitting Patches:
3333c609719bSwdenk-------------------
3334c609719bSwdenk
3335c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
3336c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
3337c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
3338c609719bSwdenk
3339c609719bSwdenk
3340c609719bSwdenkWhen you send a patch, please include the following information with
3341c609719bSwdenkit:
3342c609719bSwdenk
3343c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
3344c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
3345c609719bSwdenk  patch actually fixes something.
3346c609719bSwdenk
3347c609719bSwdenk* For new features: a description of the feature and your
3348c609719bSwdenk  implementation.
3349c609719bSwdenk
3350c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
3351c609719bSwdenk
3352c609719bSwdenk* For major contributions, your entry to the CREDITS file
3353c609719bSwdenk
3354c609719bSwdenk* When you add support for a new board, don't forget to add this
3355c609719bSwdenk  board to the MAKEALL script, too.
3356c609719bSwdenk
3357c609719bSwdenk* If your patch adds new configuration options, don't forget to
3358c609719bSwdenk  document these in the README file.
3359c609719bSwdenk
3360c609719bSwdenk* The patch itself. If you are accessing the CVS repository use "cvs
3361c609719bSwdenk  update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3362c609719bSwdenk  version of diff does not support these options, then get the latest
3363c609719bSwdenk  version of GNU diff.
3364c609719bSwdenk
33656dff5529Swdenk  The current directory when running this command shall be the top
33666dff5529Swdenk  level directory of the U-Boot source tree, or it's parent directory
33676dff5529Swdenk  (i. e. please make sure that your patch includes sufficient
33686dff5529Swdenk  directory information for the affected files).
33696dff5529Swdenk
3370c609719bSwdenk  We accept patches as plain text, MIME attachments or as uuencoded
3371c609719bSwdenk  gzipped text.
3372c609719bSwdenk
337352f52c14Swdenk* If one logical set of modifications affects or creates several
337452f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
337552f52c14Swdenk
337652f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
337752f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
337852f52c14Swdenk
337952f52c14Swdenk
3380c609719bSwdenkNotes:
3381c609719bSwdenk
3382c609719bSwdenk* Before sending the patch, run the MAKEALL script on your patched
3383c609719bSwdenk  source tree and make sure that no errors or warnings are reported
3384c609719bSwdenk  for any of the boards.
3385c609719bSwdenk
3386c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
3387c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
3388c609719bSwdenk  returned with a request to re-formatting / split it.
3389c609719bSwdenk
3390c609719bSwdenk* If you modify existing code, make sure that your new code does not
3391c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
3392c609719bSwdenk  When adding new features, these should compile conditionally only
3393c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
3394c609719bSwdenk  disabled must not need more memory than the old code without your
3395c609719bSwdenk  modification.
3396