2931 lines
97 KiB
Plaintext
2931 lines
97 KiB
Plaintext
#
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# (C) Copyright 2000 - 2002
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# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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#
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# See file CREDITS for list of people who contributed to this
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# project.
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#
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# This program is free software; you can redistribute it and/or
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# modify it under the terms of the GNU General Public License as
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# published by the Free Software Foundation; either version 2 of
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# the License, or (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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# MA 02111-1307 USA
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#
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Summary:
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========
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This directory contains the source code for U-Boot, a boot loader for
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Embedded boards based on PowerPC and ARM processors, which can be
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installed in a boot ROM and used to initialize and test the hardware
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or to download and run application code.
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The development of U-Boot is closely related to Linux: some parts of
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the source code originate in the Linux source tree, we have some
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header files in common, and special provision has been made to
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support booting of Linux images.
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Some attention has been paid to make this software easily
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configurable and extendable. For instance, all monitor commands are
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implemented with the same call interface, so that it's very easy to
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add new commands. Also, instead of permanently adding rarely used
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code (for instance hardware test utilities) to the monitor, you can
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load and run it dynamically.
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Status:
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=======
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In general, all boards for which a configuration option exists in the
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Makefile have been tested to some extent and can be considered
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"working". In fact, many of them are used in production systems.
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In case of problems see the CHANGELOG and CREDITS files to find out
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who contributed the specific port.
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Where to get help:
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==================
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In case you have questions about, problems with or contributions for
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U-Boot you should send a message to the U-Boot mailing list at
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<u-boot-users@lists.sourceforge.net>. There is also an archive of
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previous traffic on the mailing list - please search the archive
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before asking FAQ's. Please see
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http://lists.sourceforge.net/lists/listinfo/u-boot-users/
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Where we come from:
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===================
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- start from 8xxrom sources
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- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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- clean up code
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- make it easier to add custom boards
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- make it possible to add other [PowerPC] CPUs
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- extend functions, especially:
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* Provide extended interface to Linux boot loader
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* S-Record download
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* network boot
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* PCMCIA / CompactFLash / ATA disk / SCSI ... boot
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- create ARMBoot project (http://sourceforge.net/projects/armboot)
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- add other CPU families (starting with ARM)
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- create U-Boot project (http://sourceforge.net/projects/u-boot)
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Names and Spelling:
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===================
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The "official" name of this project is "Das U-Boot". The spelling
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"U-Boot" shall be used in all written text (documentation, comments
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in source files etc.). Example:
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This is the README file for the U-Boot project.
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File names etc. shall be based on the string "u-boot". Examples:
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include/asm-ppc/u-boot.h
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#include <asm/u-boot.h>
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Variable names, preprocessor constants etc. shall be either based on
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the string "u_boot" or on "U_BOOT". Example:
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U_BOOT_VERSION u_boot_logo
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IH_OS_U_BOOT u_boot_hush_start
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Versioning:
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===========
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U-Boot uses a 3 level version number containing a version, a
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sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
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sub-version "34", and patchlevel "4".
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The patchlevel is used to indicate certain stages of development
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between released versions, i. e. officially released versions of
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U-Boot will always have a patchlevel of "0".
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Directory Hierarchy:
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====================
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- board Board dependend files
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- common Misc architecture independend functions
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- cpu CPU specific files
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- disk Code for disk drive partition handling
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- doc Documentation (don't expect too much)
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- drivers Common used device drivers
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- dtt Digital Thermometer and Thermostat drivers
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- examples Example code for standalone applications, etc.
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- include Header Files
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- disk Harddisk interface code
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- net Networking code
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- ppc Files generic to PowerPC architecture
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- post Power On Self Test
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- post/arch Symlink to architecture specific Power On Self Test
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- post/arch-ppc PowerPC architecture specific Power On Self Test
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- post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
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- post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
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- rtc Real Time Clock drivers
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- tools Tools to build S-Record or U-Boot images, etc.
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- cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
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- cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
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- cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
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- cpu/mpc824x Files specific to Motorola MPC824x CPUs
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- cpu/mpc8260 Files specific to Motorola MPC8260 CPU
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- cpu/ppc4xx Files specific to IBM 4xx CPUs
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- board/LEOX/ Files specific to boards manufactured by The LEOX team
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- board/LEOX/elpt860 Files specific to ELPT860 boards
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- board/RPXClassic
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Files specific to RPXClassic boards
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- board/RPXlite Files specific to RPXlite boards
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- board/c2mon Files specific to c2mon boards
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- board/cmi Files specific to cmi boards
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- board/cogent Files specific to Cogent boards
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(need further configuration)
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Files specific to CPCIISER4 boards
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- board/cpu86 Files specific to CPU86 boards
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- board/cray/ Files specific to boards manufactured by Cray
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- board/cray/L1 Files specific to L1 boards
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- board/cu824 Files specific to CU824 boards
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- board/ebony Files specific to IBM Ebony board
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- board/eric Files specific to ERIC boards
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- board/esd/ Files specific to boards manufactured by ESD
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- board/esd/adciop Files specific to ADCIOP boards
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- board/esd/ar405 Files specific to AR405 boards
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- board/esd/canbt Files specific to CANBT boards
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- board/esd/cpci405 Files specific to CPCI405 boards
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- board/esd/cpciiser4 Files specific to CPCIISER4 boards
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- board/esd/common Common files for ESD boards
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- board/esd/dasa_sim Files specific to DASA_SIM boards
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- board/esd/du405 Files specific to DU405 boards
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- board/esd/ocrtc Files specific to OCRTC boards
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- board/esd/pci405 Files specific to PCI405 boards
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- board/esteem192e
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Files specific to ESTEEM192E boards
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- board/etx094 Files specific to ETX_094 boards
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- board/evb64260
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Files specific to EVB64260 boards
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- board/fads Files specific to FADS boards
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- board/flagadm Files specific to FLAGADM boards
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- board/gen860t Files specific to GEN860T and GEN860T_SC boards
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- board/genietv Files specific to GENIETV boards
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- board/gth Files specific to GTH boards
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- board/hermes Files specific to HERMES boards
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- board/hymod Files specific to HYMOD boards
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- board/icu862 Files specific to ICU862 boards
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- board/ip860 Files specific to IP860 boards
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- board/iphase4539
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Files specific to Interphase4539 boards
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- board/ivm Files specific to IVMS8/IVML24 boards
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- board/lantec Files specific to LANTEC boards
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- board/lwmon Files specific to LWMON boards
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- board/mbx8xx Files specific to MBX boards
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- board/mpc8260ads
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Files specific to MMPC8260ADS boards
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- board/mpl/ Files specific to boards manufactured by MPL
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- board/mpl/common Common files for MPL boards
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- board/mpl/pip405 Files specific to PIP405 boards
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- board/mpl/mip405 Files specific to MIP405 boards
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- board/musenki Files specific to MUSEKNI boards
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- board/mvs1 Files specific to MVS1 boards
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- board/nx823 Files specific to NX823 boards
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- board/oxc Files specific to OXC boards
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- board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
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- board/pm826 Files specific to PM826 boards
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- board/ppmc8260
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Files specific to PPMC8260 boards
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- board/rpxsuper
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Files specific to RPXsuper boards
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- board/rsdproto
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Files specific to RSDproto boards
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- board/sandpoint
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Files specific to Sandpoint boards
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- board/sbc8260 Files specific to SBC8260 boards
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- board/sacsng Files specific to SACSng boards
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- board/siemens Files specific to boards manufactured by Siemens AG
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- board/siemens/CCM Files specific to CCM boards
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- board/siemens/IAD210 Files specific to IAD210 boards
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- board/siemens/SCM Files specific to SCM boards
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- board/siemens/pcu_e Files specific to PCU_E boards
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- board/sixnet Files specific to SIXNET boards
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- board/spd8xx Files specific to SPD8xxTS boards
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- board/tqm8260 Files specific to TQM8260 boards
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- board/tqm8xx Files specific to TQM8xxL boards
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- board/w7o Files specific to W7O boards
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- board/walnut405
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Files specific to Walnut405 boards
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- board/westel/ Files specific to boards manufactured by Westel Wireless
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- board/westel/amx860 Files specific to AMX860 boards
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- board/utx8245 Files specific to UTX8245 boards
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Software Configuration:
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=======================
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Configuration is usually done using C preprocessor defines; the
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rationale behind that is to avoid dead code whenever possible.
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There are two classes of configuration variables:
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* Configuration _OPTIONS_:
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These are selectable by the user and have names beginning with
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"CONFIG_".
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* Configuration _SETTINGS_:
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These depend on the hardware etc. and should not be meddled with if
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you don't know what you're doing; they have names beginning with
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"CFG_".
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Later we will add a configuration tool - probably similar to or even
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identical to what's used for the Linux kernel. Right now, we have to
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do the configuration by hand, which means creating some symbolic
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links and editing some configuration files. We use the TQM8xxL boards
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as an example here.
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Selection of Processor Architecture and Board Type:
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---------------------------------------------------
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For all supported boards there are ready-to-use default
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configurations available; just type "make <board_name>_config".
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Example: For a TQM823L module type:
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cd u-boot
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make TQM823L_config
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For the Cogent platform, you need to specify the cpu type as well;
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e.g. "make cogent_mpc8xx_config". And also configure the cogent
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directory according to the instructions in cogent/README.
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Configuration Options:
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----------------------
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Configuration depends on the combination of board and CPU type; all
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such information is kept in a configuration file
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"include/configs/<board_name>.h".
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Example: For a TQM823L module, all configuration settings are in
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"include/configs/TQM823L.h".
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Many of the options are named exactly as the corresponding Linux
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kernel configuration options. The intention is to make it easier to
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build a config tool - later.
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The following options need to be configured:
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- CPU Type: Define exactly one of
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PowerPC based CPUs:
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-------------------
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CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
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or CONFIG_MPC5xx
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or CONFIG_MPC824X, CONFIG_MPC8260
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or CONFIG_IOP480
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or CONFIG_405GP
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or CONFIG_440
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or CONFIG_MPC74xx
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ARM based CPUs:
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---------------
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CONFIG_SA1110
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CONFIG_ARM7
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CONFIG_PXA250
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- Board Type: Define exactly one of
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PowerPC based boards:
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---------------------
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CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
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CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
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CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
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CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
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CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
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CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
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CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
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CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
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CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
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CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
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CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
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CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
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CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
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CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
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CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
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CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
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CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
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CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
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CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
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CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
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CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
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CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
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CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
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CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
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CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
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CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
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CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
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CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
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CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
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CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
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CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
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CONFIG_NETVIA
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ARM based boards:
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-----------------
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CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
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CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
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CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
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CONFIG_TRAB
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- CPU Module Type: (if CONFIG_COGENT is defined)
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Define exactly one of
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CONFIG_CMA286_60_OLD
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--- FIXME --- not tested yet:
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CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
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CONFIG_CMA287_23, CONFIG_CMA287_50
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- Motherboard Type: (if CONFIG_COGENT is defined)
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Define exactly one of
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CONFIG_CMA101, CONFIG_CMA102
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- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
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Define one or more of
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CONFIG_CMA302
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- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
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Define one or more of
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CONFIG_LCD_HEARTBEAT - update a character position on
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the lcd display every second with
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a "rotator" |\-/|\-/
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- MPC824X Family Member (if CONFIG_MPC824X is defined)
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Define exactly one of
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CONFIG_MPC8240, CONFIG_MPC8245
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- 8xx CPU Options: (if using an 8xx cpu)
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Define one or more of
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CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() can not work e.g.
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no 32KHz reference PIT/RTC clock
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- Clock Interface:
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CONFIG_CLOCKS_IN_MHZ
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U-Boot stores all clock information in Hz
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internally. For binary compatibility with older Linux
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kernels (which expect the clocks passed in the
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bd_info data to be in MHz) the environment variable
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"clocks_in_mhz" can be defined so that U-Boot
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converts clock data to MHZ before passing it to the
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Linux kernel.
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When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
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"clocks_in_mhz=1" is automatically included in the
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default environment.
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- Console Interface:
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Depending on board, define exactly one serial port
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(like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
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CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
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console by defining CONFIG_8xx_CONS_NONE
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Note: if CONFIG_8xx_CONS_NONE is defined, the serial
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port routines must be defined elsewhere
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(i.e. serial_init(), serial_getc(), ...)
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CONFIG_CFB_CONSOLE
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Enables console device for a color framebuffer. Needs following
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defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
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VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
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(default big endian)
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VIDEO_HW_RECTFILL graphic chip supports
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rectangle fill
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(cf. smiLynxEM)
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VIDEO_HW_BITBLT graphic chip supports
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bit-blit (cf. smiLynxEM)
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VIDEO_VISIBLE_COLS visible pixel columns
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(cols=pitch)
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VIDEO_VISIBLE_ROWS visible pixel rows
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VIDEO_PIXEL_SIZE bytes per pixel
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VIDEO_DATA_FORMAT graphic data format
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(0-5, cf. cfb_console.c)
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VIDEO_FB_ADRS framebuffer address
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VIDEO_KBD_INIT_FCT keyboard int fct
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(i.e. i8042_kbd_init())
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VIDEO_TSTC_FCT test char fct
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(i.e. i8042_tstc)
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VIDEO_GETC_FCT get char fct
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(i.e. i8042_getc)
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CONFIG_CONSOLE_CURSOR cursor drawing on/off
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(requires blink timer
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cf. i8042.c)
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CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
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CONFIG_CONSOLE_TIME display time/date info in
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upper right corner
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(requires CFG_CMD_DATE)
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CONFIG_VIDEO_LOGO display Linux logo in
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upper left corner
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CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
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linux_logo.h for logo.
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Requires CONFIG_VIDEO_LOGO
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CONFIG_CONSOLE_EXTRA_INFO
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addional board info beside
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the logo
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When CONFIG_CFB_CONSOLE is defined, video console is
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default i/o. Serial console can be forced with
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environment 'console=serial'.
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- Console Baudrate:
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CONFIG_BAUDRATE - in bps
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Select one of the baudrates listed in
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CFG_BAUDRATE_TABLE, see below.
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- Interrupt driven serial port input:
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CONFIG_SERIAL_SOFTWARE_FIFO
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PPC405GP only.
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Use an interrupt handler for receiving data on the
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serial port. It also enables using hardware handshake
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(RTS/CTS) and UART's built-in FIFO. Set the number of
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bytes the interrupt driven input buffer should have.
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Set to 0 to disable this feature (this is the default).
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This will also disable hardware handshake.
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- Console UART Number:
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CONFIG_UART1_CONSOLE
|
|
|
|
IBM PPC4xx only.
|
|
If defined internal UART1 (and not UART0) is used
|
|
as default U-Boot console.
|
|
|
|
- Boot Delay: CONFIG_BOOTDELAY - in seconds
|
|
Delay before automatically booting the default image;
|
|
set to -1 to disable autoboot.
|
|
|
|
See doc/README.autoboot for these options that
|
|
work with CONFIG_BOOTDELAY. None are required.
|
|
CONFIG_BOOT_RETRY_TIME
|
|
CONFIG_BOOT_RETRY_MIN
|
|
CONFIG_AUTOBOOT_KEYED
|
|
CONFIG_AUTOBOOT_PROMPT
|
|
CONFIG_AUTOBOOT_DELAY_STR
|
|
CONFIG_AUTOBOOT_STOP_STR
|
|
CONFIG_AUTOBOOT_DELAY_STR2
|
|
CONFIG_AUTOBOOT_STOP_STR2
|
|
CONFIG_ZERO_BOOTDELAY_CHECK
|
|
CONFIG_RESET_TO_RETRY
|
|
|
|
- Autoboot Command:
|
|
CONFIG_BOOTCOMMAND
|
|
Only needed when CONFIG_BOOTDELAY is enabled;
|
|
define a command string that is automatically executed
|
|
when no character is read on the console interface
|
|
within "Boot Delay" after reset.
|
|
|
|
CONFIG_BOOTARGS
|
|
This can be used to pass arguments to the bootm
|
|
command. The value of CONFIG_BOOTARGS goes into the
|
|
environment value "bootargs".
|
|
|
|
CONFIG_RAMBOOT and CONFIG_NFSBOOT
|
|
The value of these goes into the environment as
|
|
"ramboot" and "nfsboot" respectively, and can be used
|
|
as a convenience, when switching between booting from
|
|
ram and nfs.
|
|
|
|
- Pre-Boot Commands:
|
|
CONFIG_PREBOOT
|
|
|
|
When this option is #defined, the existence of the
|
|
environment variable "preboot" will be checked
|
|
immediately before starting the CONFIG_BOOTDELAY
|
|
countdown and/or running the auto-boot command resp.
|
|
entering interactive mode.
|
|
|
|
This feature is especially useful when "preboot" is
|
|
automatically generated or modified. For an example
|
|
see the LWMON board specific code: here "preboot" is
|
|
modified when the user holds down a certain
|
|
combination of keys on the (special) keyboard when
|
|
booting the systems
|
|
|
|
- Serial Download Echo Mode:
|
|
CONFIG_LOADS_ECHO
|
|
If defined to 1, all characters received during a
|
|
serial download (using the "loads" command) are
|
|
echoed back. This might be needed by some terminal
|
|
emulations (like "cu"), but may as well just take
|
|
time on others. This setting #define's the initial
|
|
value of the "loads_echo" environment variable.
|
|
|
|
- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
|
|
CONFIG_KGDB_BAUDRATE
|
|
Select one of the baudrates listed in
|
|
CFG_BAUDRATE_TABLE, see below.
|
|
|
|
- Monitor Functions:
|
|
CONFIG_COMMANDS
|
|
Most monitor functions can be selected (or
|
|
de-selected) by adjusting the definition of
|
|
CONFIG_COMMANDS; to select individual functions,
|
|
#define CONFIG_COMMANDS by "OR"ing any of the
|
|
following values:
|
|
|
|
#define enables commands:
|
|
-------------------------
|
|
CFG_CMD_ASKENV * ask for env variable
|
|
CFG_CMD_BDI bdinfo
|
|
CFG_CMD_BEDBUG Include BedBug Debugger
|
|
CFG_CMD_BOOTD bootd
|
|
CFG_CMD_CACHE icache, dcache
|
|
CFG_CMD_CONSOLE coninfo
|
|
CFG_CMD_DATE * support for RTC, date/time...
|
|
CFG_CMD_DHCP DHCP support
|
|
CFG_CMD_ECHO * echo arguments
|
|
CFG_CMD_EEPROM * EEPROM read/write support
|
|
CFG_CMD_ELF bootelf, bootvx
|
|
CFG_CMD_ENV saveenv
|
|
CFG_CMD_FDC * Floppy Disk Support
|
|
CFG_CMD_FDOS * Dos diskette Support
|
|
CFG_CMD_FLASH flinfo, erase, protect
|
|
CFG_CMD_FPGA FPGA device initialization support
|
|
CFG_CMD_I2C * I2C serial bus support
|
|
CFG_CMD_IDE * IDE harddisk support
|
|
CFG_CMD_IMI iminfo
|
|
CFG_CMD_IMMAP * IMMR dump support
|
|
CFG_CMD_IRQ * irqinfo
|
|
CFG_CMD_KGDB * kgdb
|
|
CFG_CMD_LOADB loadb
|
|
CFG_CMD_LOADS loads
|
|
CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
|
|
loop, mtest
|
|
CFG_CMD_MII MII utility commands
|
|
CFG_CMD_NET bootp, tftpboot, rarpboot
|
|
CFG_CMD_PCI * pciinfo
|
|
CFG_CMD_PCMCIA * PCMCIA support
|
|
CFG_CMD_REGINFO * Register dump
|
|
CFG_CMD_RUN run command in env variable
|
|
CFG_CMD_SCSI * SCSI Support
|
|
CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
|
|
CFG_CMD_SPI * SPI serial bus support
|
|
CFG_CMD_USB * USB support
|
|
CFG_CMD_BSP * Board SPecific functions
|
|
-----------------------------------------------
|
|
CFG_CMD_ALL all
|
|
|
|
CFG_CMD_DFL Default configuration; at the moment
|
|
this is includes all commands, except
|
|
the ones marked with "*" in the list
|
|
above.
|
|
|
|
If you don't define CONFIG_COMMANDS it defaults to
|
|
CFG_CMD_DFL in include/cmd_confdefs.h. A board can
|
|
override the default settings in the respective
|
|
include file.
|
|
|
|
EXAMPLE: If you want all functions except of network
|
|
support you can write:
|
|
|
|
#define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
|
|
|
|
|
|
Note: Don't enable the "icache" and "dcache" commands
|
|
(configuration option CFG_CMD_CACHE) unless you know
|
|
what you (and your U-Boot users) are doing. Data
|
|
cache cannot be enabled on systems like the 8xx or
|
|
8260 (where accesses to the IMMR region must be
|
|
uncached), and it cannot be disabled on all other
|
|
systems where we (mis-) use the data cache to hold an
|
|
initial stack and some data.
|
|
|
|
|
|
XXX - this list needs to get updated!
|
|
|
|
- Watchdog:
|
|
CONFIG_WATCHDOG
|
|
If this variable is defined, it enables watchdog
|
|
support. There must support in the platform specific
|
|
code for a watchdog. For the 8xx and 8260 CPUs, the
|
|
SIU Watchdog feature is enabled in the SYPCR
|
|
register.
|
|
|
|
- U-Boot Version:
|
|
CONFIG_VERSION_VARIABLE
|
|
If this variable is defined, an environment variable
|
|
named "ver" is created by U-Boot showing the U-Boot
|
|
version as printed by the "version" command.
|
|
This variable is readonly.
|
|
|
|
- Real-Time Clock:
|
|
|
|
When CFG_CMD_DATE is selected, the type of the RTC
|
|
has to be selected, too. Define exactly one of the
|
|
following options:
|
|
|
|
CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
|
|
CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
|
|
CONFIG_RTC_MC146818 - use MC146818 RTC
|
|
CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
|
|
CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
|
|
CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
|
|
CONFIG_RTC_DS164x - use Dallas DS164x RTC
|
|
|
|
- Timestamp Support:
|
|
|
|
When CONFIG_TIMESTAMP is selected, the timestamp
|
|
(date and time) of an image is printed by image
|
|
commands like bootm or iminfo. This option is
|
|
automatically enabled when you select CFG_CMD_DATE .
|
|
|
|
- Partition Support:
|
|
CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
|
|
and/or CONFIG_ISO_PARTITION
|
|
|
|
If IDE or SCSI support is enabled (CFG_CMD_IDE or
|
|
CFG_CMD_SCSI) you must configure support for at least
|
|
one partition type as well.
|
|
|
|
- IDE Reset method:
|
|
CONFIG_IDE_RESET_ROUTINE
|
|
|
|
Set this to define that instead of a reset Pin, the
|
|
routine ide_set_reset(int idereset) will be used.
|
|
|
|
- ATAPI Support:
|
|
CONFIG_ATAPI
|
|
|
|
Set this to enable ATAPI support.
|
|
|
|
- SCSI Support:
|
|
At the moment only there is only support for the
|
|
SYM53C8XX SCSI controller; define
|
|
CONFIG_SCSI_SYM53C8XX to enable it.
|
|
|
|
CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
|
|
CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
|
|
CFG_SCSI_MAX_LUN] can be adjusted to define the
|
|
maximum numbers of LUNs, SCSI ID's and target
|
|
devices.
|
|
CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
|
|
|
|
- NETWORK Support (PCI):
|
|
CONFIG_EEPRO100
|
|
Support for Intel 82557/82559/82559ER chips.
|
|
Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
|
|
write routine for first time initialisation.
|
|
|
|
CONFIG_TULIP
|
|
Support for Digital 2114x chips.
|
|
Optional CONFIG_TULIP_SELECT_MEDIA for board specific
|
|
modem chip initialisation (KS8761/QS6611).
|
|
|
|
CONFIG_NATSEMI
|
|
Support for National dp83815 chips.
|
|
|
|
CONFIG_NS8382X
|
|
Support for National dp8382[01] gigabit chips.
|
|
|
|
- NETWORK Support (other):
|
|
|
|
CONFIG_DRIVER_LAN91C96
|
|
Support for SMSC's LAN91C96 chips.
|
|
|
|
CONFIG_LAN91C96_BASE
|
|
Define this to hold the physical address
|
|
of the LAN91C96's I/O space
|
|
|
|
CONFIG_LAN91C96_USE_32_BIT
|
|
Define this to enable 32 bit addressing
|
|
|
|
- USB Support:
|
|
At the moment only the UHCI host controller is
|
|
supported (PIP405, MIP405); define
|
|
CONFIG_USB_UHCI to enable it.
|
|
define CONFIG_USB_KEYBOARD to enable the USB Keyboard
|
|
end define CONFIG_USB_STORAGE to enable the USB
|
|
storage devices.
|
|
Note:
|
|
Supported are USB Keyboards and USB Floppy drives
|
|
(TEAC FD-05PUB).
|
|
|
|
- Keyboard Support:
|
|
CONFIG_ISA_KEYBOARD
|
|
|
|
Define this to enable standard (PC-Style) keyboard
|
|
support
|
|
|
|
CONFIG_I8042_KBD
|
|
Standard PC keyboard driver with US (is default) and
|
|
GERMAN key layout (switch via environment 'keymap=de') support.
|
|
Export function i8042_kbd_init, i8042_tstc and i8042_getc
|
|
for cfb_console. Supports cursor blinking.
|
|
|
|
- Video support:
|
|
CONFIG_VIDEO
|
|
|
|
Define this to enable video support (for output to
|
|
video).
|
|
|
|
CONFIG_VIDEO_CT69000
|
|
|
|
Enable Chips & Technologies 69000 Video chip
|
|
|
|
CONFIG_VIDEO_SMI_LYNXEM
|
|
Enable Silicon Motion SMI 712/710/810 Video chip
|
|
Videomode are selected via environment 'videomode' with
|
|
standard LiLo mode numbers.
|
|
Following modes are supported (* is default):
|
|
|
|
800x600 1024x768 1280x1024
|
|
256 (8bit) 303* 305 307
|
|
65536 (16bit) 314 317 31a
|
|
16,7 Mill (24bit) 315 318 31b
|
|
(i.e. setenv videomode 317; saveenv; reset;)
|
|
|
|
CONFIG_VIDEO_SED13806
|
|
Enable Epson SED13806 driver. This driver supports 8bpp
|
|
and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
|
|
or CONFIG_VIDEO_SED13806_16BPP
|
|
|
|
|
|
- LCD Support: CONFIG_LCD
|
|
|
|
Define this to enable LCD support (for output to LCD
|
|
display); also select one of the supported displays
|
|
by defining one of these:
|
|
|
|
CONFIG_NEC_NL6648AC33:
|
|
|
|
NEC NL6648AC33-18. Active, color, single scan.
|
|
|
|
CONFIG_NEC_NL6648BC20
|
|
|
|
NEC NL6648BC20-08. 6.5", 640x480.
|
|
Active, color, single scan.
|
|
|
|
CONFIG_SHARP_16x9
|
|
|
|
Sharp 320x240. Active, color, single scan.
|
|
It isn't 16x9, and I am not sure what it is.
|
|
|
|
CONFIG_SHARP_LQ64D341
|
|
|
|
Sharp LQ64D341 display, 640x480.
|
|
Active, color, single scan.
|
|
|
|
CONFIG_HLD1045
|
|
|
|
HLD1045 display, 640x480.
|
|
Active, color, single scan.
|
|
|
|
CONFIG_OPTREX_BW
|
|
|
|
Optrex CBL50840-2 NF-FW 99 22 M5
|
|
or
|
|
Hitachi LMG6912RPFC-00T
|
|
or
|
|
Hitachi SP14Q002
|
|
|
|
320x240. Black & white.
|
|
|
|
Normally display is black on white background; define
|
|
CFG_WHITE_ON_BLACK to get it inverted.
|
|
|
|
- Spash Screen Support: CONFIG_SPLASH_SCREEN
|
|
|
|
If this option is set, the environment is checked for
|
|
a variable "splashimage". If found, the usual display
|
|
of logo, copyright and system information on the LCD
|
|
is supressed and the BMP image at the address
|
|
specified in "splashimage" is loaded instead. The
|
|
console is redirected to the "nulldev", too. This
|
|
allows for a "silent" boot where a splash screen is
|
|
loaded very quickly after power-on.
|
|
|
|
|
|
- Ethernet address:
|
|
CONFIG_ETHADDR
|
|
CONFIG_ETH2ADDR
|
|
CONFIG_ETH3ADDR
|
|
|
|
Define a default value for ethernet address to use
|
|
for the respective ethernet interface, in case this
|
|
is not determined automatically.
|
|
|
|
- IP address:
|
|
CONFIG_IPADDR
|
|
|
|
Define a default value for the IP address to use for
|
|
the default ethernet interface, in case this is not
|
|
determined through e.g. bootp.
|
|
|
|
- Server IP address:
|
|
CONFIG_SERVERIP
|
|
|
|
Defines a default value for theIP address of a TFTP
|
|
server to contact when using the "tftboot" command.
|
|
|
|
- BOOTP Recovery Mode:
|
|
CONFIG_BOOTP_RANDOM_DELAY
|
|
|
|
If you have many targets in a network that try to
|
|
boot using BOOTP, you may want to avoid that all
|
|
systems send out BOOTP requests at precisely the same
|
|
moment (which would happen for instance at recovery
|
|
from a power failure, when all systems will try to
|
|
boot, thus flooding the BOOTP server. Defining
|
|
CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
|
|
inserted before sending out BOOTP requests. The
|
|
following delays are insterted then:
|
|
|
|
1st BOOTP request: delay 0 ... 1 sec
|
|
2nd BOOTP request: delay 0 ... 2 sec
|
|
3rd BOOTP request: delay 0 ... 4 sec
|
|
4th and following
|
|
BOOTP requests: delay 0 ... 8 sec
|
|
|
|
- Status LED: CONFIG_STATUS_LED
|
|
|
|
Several configurations allow to display the current
|
|
status using a LED. For instance, the LED will blink
|
|
fast while running U-Boot code, stop blinking as
|
|
soon as a reply to a BOOTP request was received, and
|
|
start blinking slow once the Linux kernel is running
|
|
(supported by a status LED driver in the Linux
|
|
kernel). Defining CONFIG_STATUS_LED enables this
|
|
feature in U-Boot.
|
|
|
|
- CAN Support: CONFIG_CAN_DRIVER
|
|
|
|
Defining CONFIG_CAN_DRIVER enables CAN driver support
|
|
on those systems that support this (optional)
|
|
feature, like the TQM8xxL modules.
|
|
|
|
- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
|
|
|
|
Enables I2C serial bus commands. If this is selected,
|
|
either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must be defined
|
|
to include the appropriate I2C driver.
|
|
|
|
See also: common/cmd_i2c.c for a description of the
|
|
command line interface.
|
|
|
|
|
|
CONFIG_HARD_I2C
|
|
|
|
Selects the CPM hardware driver for I2C.
|
|
|
|
CONFIG_SOFT_I2C
|
|
|
|
Use software (aka bit-banging) driver instead of CPM
|
|
or similar hardware support for I2C. This is configured
|
|
via the following defines.
|
|
|
|
I2C_INIT
|
|
|
|
(Optional). Any commands necessary to enable I2C
|
|
controller or configure ports.
|
|
|
|
I2C_PORT
|
|
|
|
(Only for MPC8260 CPU). The I/O port to use (the code
|
|
assumes both bits are on the same port). Valid values
|
|
are 0..3 for ports A..D.
|
|
|
|
I2C_ACTIVE
|
|
|
|
The code necessary to make the I2C data line active
|
|
(driven). If the data line is open collector, this
|
|
define can be null.
|
|
|
|
I2C_TRISTATE
|
|
|
|
The code necessary to make the I2C data line tri-stated
|
|
(inactive). If the data line is open collector, this
|
|
define can be null.
|
|
|
|
I2C_READ
|
|
|
|
Code that returns TRUE if the I2C data line is high,
|
|
FALSE if it is low.
|
|
|
|
I2C_SDA(bit)
|
|
|
|
If <bit> is TRUE, sets the I2C data line high. If it
|
|
is FALSE, it clears it (low).
|
|
|
|
I2C_SCL(bit)
|
|
|
|
If <bit> is TRUE, sets the I2C clock line high. If it
|
|
is FALSE, it clears it (low).
|
|
|
|
I2C_DELAY
|
|
|
|
This delay is invoked four times per clock cycle so this
|
|
controls the rate of data transfer. The data rate thus
|
|
is 1 / (I2C_DELAY * 4).
|
|
|
|
CFG_I2C_INIT_BOARD
|
|
|
|
When a board is reset during an i2c bus transfer
|
|
chips might think that the current transfer is still
|
|
in progress. On some boards it is possible to access
|
|
the i2c SCLK line directly, either by using the
|
|
processor pin as a GPIO or by having a second pin
|
|
connected to the bus. If this option is defined a
|
|
custom i2c_init_board() routine in boards/xxx/board.c
|
|
is run early in the boot sequence.
|
|
|
|
- SPI Support: CONFIG_SPI
|
|
|
|
Enables SPI driver (so far only tested with
|
|
SPI EEPROM, also an instance works with Crystal A/D and
|
|
D/As on the SACSng board)
|
|
|
|
CONFIG_SPI_X
|
|
|
|
Enables extended (16-bit) SPI EEPROM addressing.
|
|
(symmetrical to CONFIG_I2C_X)
|
|
|
|
CONFIG_SOFT_SPI
|
|
|
|
Enables a software (bit-bang) SPI driver rather than
|
|
using hardware support. This is a general purpose
|
|
driver that only requires three general I/O port pins
|
|
(two outputs, one input) to function. If this is
|
|
defined, the board configuration must define several
|
|
SPI configuration items (port pins to use, etc). For
|
|
an example, see include/configs/sacsng.h.
|
|
|
|
- FPGA Support: CONFIG_FPGA_COUNT
|
|
|
|
Specify the number of FPGA devices to support.
|
|
|
|
CONFIG_FPGA
|
|
|
|
Used to specify the types of FPGA devices. For
|
|
example,
|
|
#define CONFIG_FPGA CFG_XILINX_VIRTEX2
|
|
|
|
CFG_FPGA_PROG_FEEDBACK
|
|
|
|
Enable printing of hash marks during FPGA
|
|
configuration.
|
|
|
|
CFG_FPGA_CHECK_BUSY
|
|
|
|
Enable checks on FPGA configuration interface busy
|
|
status by the configuration function. This option
|
|
will require a board or device specific function to
|
|
be written.
|
|
|
|
CONFIG_FPGA_DELAY
|
|
|
|
If defined, a function that provides delays in the
|
|
FPGA configuration driver.
|
|
|
|
CFG_FPGA_CHECK_CTRLC
|
|
|
|
Allow Control-C to interrupt FPGA configuration
|
|
|
|
CFG_FPGA_CHECK_ERROR
|
|
|
|
Check for configuration errors during FPGA bitfile
|
|
loading. For example, abort during Virtex II
|
|
configuration if the INIT_B line goes low (which
|
|
indicated a CRC error).
|
|
|
|
CFG_FPGA_WAIT_INIT
|
|
|
|
Maximum time to wait for the INIT_B line to deassert
|
|
after PROB_B has been deasserted during a Virtex II
|
|
FPGA configuration sequence. The default time is 500 mS.
|
|
|
|
CFG_FPGA_WAIT_BUSY
|
|
|
|
Maximum time to wait for BUSY to deassert during
|
|
Virtex II FPGA configuration. The default is 5 mS.
|
|
|
|
CFG_FPGA_WAIT_CONFIG
|
|
|
|
Time to wait after FPGA configuration. The default is
|
|
200 mS.
|
|
|
|
- FPGA Support: CONFIG_FPGA_COUNT
|
|
|
|
Specify the number of FPGA devices to support.
|
|
|
|
CONFIG_FPGA
|
|
|
|
Used to specify the types of FPGA devices. For example,
|
|
#define CONFIG_FPGA CFG_XILINX_VIRTEX2
|
|
|
|
CFG_FPGA_PROG_FEEDBACK
|
|
|
|
Enable printing of hash marks during FPGA configuration.
|
|
|
|
CFG_FPGA_CHECK_BUSY
|
|
|
|
Enable checks on FPGA configuration interface busy
|
|
status by the configuration function. This option
|
|
will require a board or device specific function to
|
|
be written.
|
|
|
|
CONFIG_FPGA_DELAY
|
|
|
|
If defined, a function that provides delays in the FPGA
|
|
configuration driver.
|
|
|
|
CFG_FPGA_CHECK_CTRLC
|
|
Allow Control-C to interrupt FPGA configuration
|
|
|
|
CFG_FPGA_CHECK_ERROR
|
|
|
|
Check for configuration errors during FPGA bitfile
|
|
loading. For example, abort during Virtex II
|
|
configuration if the INIT_B line goes low (which
|
|
indicated a CRC error).
|
|
|
|
CFG_FPGA_WAIT_INIT
|
|
|
|
Maximum time to wait for the INIT_B line to deassert
|
|
after PROB_B has been deasserted during a Virtex II
|
|
FPGA configuration sequence. The default time is 500
|
|
mS.
|
|
|
|
CFG_FPGA_WAIT_BUSY
|
|
|
|
Maximum time to wait for BUSY to deassert during
|
|
Virtex II FPGA configuration. The default is 5 mS.
|
|
|
|
CFG_FPGA_WAIT_CONFIG
|
|
|
|
Time to wait after FPGA configuration. The default is
|
|
200 mS.
|
|
|
|
- Configuration Management:
|
|
CONFIG_IDENT_STRING
|
|
|
|
If defined, this string will be added to the U-Boot
|
|
version information (U_BOOT_VERSION)
|
|
|
|
- Vendor Parameter Protection:
|
|
|
|
U-Boot considers the values of the environment
|
|
variables "serial#" (Board Serial Number) and
|
|
"ethaddr" (Ethernet Address) to bb parameters that
|
|
are set once by the board vendor / manufacturer, and
|
|
protects these variables from casual modification by
|
|
the user. Once set, these variables are read-only,
|
|
and write or delete attempts are rejected. You can
|
|
change this behviour:
|
|
|
|
If CONFIG_ENV_OVERWRITE is #defined in your config
|
|
file, the write protection for vendor parameters is
|
|
completely disabled. Anybody can change or delete
|
|
these parameters.
|
|
|
|
Alternatively, if you #define _both_ CONFIG_ETHADDR
|
|
_and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
|
|
ethernet address is installed in the environment,
|
|
which can be changed exactly ONCE by the user. [The
|
|
serial# is unaffected by this, i. e. it remains
|
|
read-only.]
|
|
|
|
- Protected RAM:
|
|
CONFIG_PRAM
|
|
|
|
Define this variable to enable the reservation of
|
|
"protected RAM", i. e. RAM which is not overwritten
|
|
by U-Boot. Define CONFIG_PRAM to hold the number of
|
|
kB you want to reserve for pRAM. You can overwrite
|
|
this default value by defining an environment
|
|
variable "pram" to the number of kB you want to
|
|
reserve. Note that the board info structure will
|
|
still show the full amount of RAM. If pRAM is
|
|
reserved, a new environment variable "mem" will
|
|
automatically be defined to hold the amount of
|
|
remaining RAM in a form that can be passed as boot
|
|
argument to Linux, for instance like that:
|
|
|
|
setenv bootargs ... mem=\$(mem)
|
|
saveenv
|
|
|
|
This way you can tell Linux not to use this memory,
|
|
either, which results in a memory region that will
|
|
not be affected by reboots.
|
|
|
|
*WARNING* If your board configuration uses automatic
|
|
detection of the RAM size, you must make sure that
|
|
this memory test is non-destructive. So far, the
|
|
following board configurations are known to be
|
|
"pRAM-clean":
|
|
|
|
ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
|
|
HERMES, IP860, RPXlite, LWMON, LANTEC,
|
|
PCU_E, FLAGADM, TQM8260
|
|
|
|
- Error Recovery:
|
|
CONFIG_PANIC_HANG
|
|
|
|
Define this variable to stop the system in case of a
|
|
fatal error, so that you have to reset it manually.
|
|
This is probably NOT a good idea for an embedded
|
|
system where you want to system to reboot
|
|
automatically as fast as possible, but it may be
|
|
useful during development since you can try to debug
|
|
the conditions that lead to the situation.
|
|
|
|
CONFIG_NET_RETRY_COUNT
|
|
|
|
This variable defines the number of retries for
|
|
network operations like ARP, RARP, TFTP, or BOOTP
|
|
before giving up the operation. If not defined, a
|
|
default value of 5 is used.
|
|
|
|
- Command Interpreter:
|
|
CFG_HUSH_PARSER
|
|
|
|
Define this variable to enable the "hush" shell (from
|
|
Busybox) as command line interpreter, thus enabling
|
|
powerful command line syntax like
|
|
if...then...else...fi conditionals or `&&' and '||'
|
|
constructs ("shell scripts").
|
|
|
|
If undefined, you get the old, much simpler behaviour
|
|
with a somewhat smaller memory footprint.
|
|
|
|
|
|
CFG_PROMPT_HUSH_PS2
|
|
|
|
This defines the secondary prompt string, which is
|
|
printed when the command interpreter needs more input
|
|
to complete a command. Usually "> ".
|
|
|
|
Note:
|
|
|
|
In the current implementation, the local variables
|
|
space and global environment variables space are
|
|
separated. Local variables are those you define by
|
|
simply typing like `name=value'. To access a local
|
|
variable later on, you have write `$name' or
|
|
`${name}'; variable directly by typing say `$name' at
|
|
the command prompt.
|
|
|
|
Global environment variables are those you use
|
|
setenv/printenv to work with. To run a command stored
|
|
in such a variable, you need to use the run command,
|
|
and you must not use the '$' sign to access them.
|
|
|
|
To store commands and special characters in a
|
|
variable, please use double quotation marks
|
|
surrounding the whole text of the variable, instead
|
|
of the backslashes before semicolons and special
|
|
symbols.
|
|
|
|
- Default Environment
|
|
CONFIG_EXTRA_ENV_SETTINGS
|
|
|
|
Define this to contain any number of null terminated
|
|
strings (variable = value pairs) that will be part of
|
|
the default enviroment compiled into the boot image.
|
|
|
|
For example, place something like this in your
|
|
board's config file:
|
|
|
|
#define CONFIG_EXTRA_ENV_SETTINGS \
|
|
"myvar1=value1\0" \
|
|
"myvar2=value2\0"
|
|
|
|
Warning: This method is based on knowledge about the
|
|
internal format how the environment is stored by the
|
|
U-Boot code. This is NOT an official, exported
|
|
interface! Although it is unlikely that this format
|
|
will change soon, but there is no guarantee either.
|
|
You better know what you are doing here.
|
|
|
|
Note: overly (ab)use of the default environment is
|
|
discouraged. Make sure to check other ways to preset
|
|
the environment like the autoscript function or the
|
|
boot command first.
|
|
|
|
- Show boot progress
|
|
CONFIG_SHOW_BOOT_PROGRESS
|
|
|
|
Defining this option allows to add some board-
|
|
specific code (calling a user-provided function
|
|
"show_boot_progress(int)") that enables you to show
|
|
the system's boot progress on some display (for
|
|
example, some LED's) on your board. At the moment,
|
|
the following checkpoints are implemented:
|
|
|
|
Arg Where When
|
|
1 common/cmd_bootm.c before attempting to boot an image
|
|
-1 common/cmd_bootm.c Image header has bad magic number
|
|
2 common/cmd_bootm.c Image header has correct magic number
|
|
-2 common/cmd_bootm.c Image header has bad checksum
|
|
3 common/cmd_bootm.c Image header has correct checksum
|
|
-3 common/cmd_bootm.c Image data has bad checksum
|
|
4 common/cmd_bootm.c Image data has correct checksum
|
|
-4 common/cmd_bootm.c Image is for unsupported architecture
|
|
5 common/cmd_bootm.c Architecture check OK
|
|
-5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
|
|
6 common/cmd_bootm.c Image Type check OK
|
|
-6 common/cmd_bootm.c gunzip uncompression error
|
|
-7 common/cmd_bootm.c Unimplemented compression type
|
|
7 common/cmd_bootm.c Uncompression OK
|
|
-8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
|
|
8 common/cmd_bootm.c Image Type check OK
|
|
-9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
|
|
9 common/cmd_bootm.c Start initial ramdisk verification
|
|
-10 common/cmd_bootm.c Ramdisk header has bad magic number
|
|
-11 common/cmd_bootm.c Ramdisk header has bad checksum
|
|
10 common/cmd_bootm.c Ramdisk header is OK
|
|
-12 common/cmd_bootm.c Ramdisk data has bad checksum
|
|
11 common/cmd_bootm.c Ramdisk data has correct checksum
|
|
12 common/cmd_bootm.c Ramdisk verification complete, start loading
|
|
-13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
|
|
13 common/cmd_bootm.c Start multifile image verification
|
|
14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
|
|
15 common/cmd_bootm.c All preparation done, transferring control to OS
|
|
|
|
-1 common/cmd_doc.c Bad usage of "doc" command
|
|
-1 common/cmd_doc.c No boot device
|
|
-1 common/cmd_doc.c Unknown Chip ID on boot device
|
|
-1 common/cmd_doc.c Read Error on boot device
|
|
-1 common/cmd_doc.c Image header has bad magic number
|
|
|
|
-1 common/cmd_ide.c Bad usage of "ide" command
|
|
-1 common/cmd_ide.c No boot device
|
|
-1 common/cmd_ide.c Unknown boot device
|
|
-1 common/cmd_ide.c Unknown partition table
|
|
-1 common/cmd_ide.c Invalid partition type
|
|
-1 common/cmd_ide.c Read Error on boot device
|
|
-1 common/cmd_ide.c Image header has bad magic number
|
|
|
|
-1 common/cmd_nvedit.c Environment not changable, but has bad CRC
|
|
|
|
|
|
Modem Support:
|
|
--------------
|
|
|
|
[so far only for SMDK2400 and TRAB boards]
|
|
|
|
- Modem support endable:
|
|
CONFIG_MODEM_SUPPORT
|
|
|
|
- RTS/CTS Flow control enable:
|
|
CONFIG_HWFLOW
|
|
|
|
- Modem debug support:
|
|
CONFIG_MODEM_SUPPORT_DEBUG
|
|
|
|
Enables debugging stuff (char screen[1024], dbg())
|
|
for modem support. Useful only with BDI2000.
|
|
|
|
- General:
|
|
|
|
In the target system modem support is enabled when a
|
|
specific key (key combination) is pressed during
|
|
power-on. Otherwise U-Boot will boot normally
|
|
(autoboot). The key_pressed() fuction is called from
|
|
board_init(). Currently key_pressed() is a dummy
|
|
function, returning 1 and thus enabling modem
|
|
initialization.
|
|
|
|
If there are no modem init strings in the
|
|
environment, U-Boot proceed to autoboot; the
|
|
previous output (banner, info printfs) will be
|
|
supressed, though.
|
|
|
|
See also: doc/README.Modem
|
|
|
|
|
|
|
|
|
|
Configuration Settings:
|
|
-----------------------
|
|
|
|
- CFG_LONGHELP: Defined when you want long help messages included;
|
|
undefine this when you're short of memory.
|
|
|
|
- CFG_PROMPT: This is what U-Boot prints on the console to
|
|
prompt for user input.
|
|
|
|
- CFG_CBSIZE: Buffer size for input from the Console
|
|
|
|
- CFG_PBSIZE: Buffer size for Console output
|
|
|
|
- CFG_MAXARGS: max. Number of arguments accepted for monitor commands
|
|
|
|
- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
|
|
the application (usually a Linux kernel) when it is
|
|
booted
|
|
|
|
- CFG_BAUDRATE_TABLE:
|
|
List of legal baudrate settings for this board.
|
|
|
|
- CFG_CONSOLE_INFO_QUIET
|
|
Suppress display of console information at boot.
|
|
|
|
- CFG_CONSOLE_IS_IN_ENV
|
|
If the board specific function
|
|
extern int overwrite_console (void);
|
|
returns 1, the stdin, stderr and stdout are switched to the
|
|
serial port, else the settings in the environment are used.
|
|
|
|
- CFG_CONSOLE_OVERWRITE_ROUTINE
|
|
Enable the call to overwrite_console().
|
|
|
|
- CFG_CONSOLE_ENV_OVERWRITE
|
|
Enable overwrite of previous console environment settings.
|
|
|
|
- CFG_MEMTEST_START, CFG_MEMTEST_END:
|
|
Begin and End addresses of the area used by the
|
|
simple memory test.
|
|
|
|
- CFG_ALT_MEMTEST:
|
|
Enable an alternate, more extensive memory test.
|
|
|
|
- CFG_TFTP_LOADADDR:
|
|
Default load address for network file downloads
|
|
|
|
- CFG_LOADS_BAUD_CHANGE:
|
|
Enable temporary baudrate change while serial download
|
|
|
|
- CFG_SDRAM_BASE:
|
|
Physical start address of SDRAM. _Must_ be 0 here.
|
|
|
|
- CFG_MBIO_BASE:
|
|
Physical start address of Motherboard I/O (if using a
|
|
Cogent motherboard)
|
|
|
|
- CFG_FLASH_BASE:
|
|
Physical start address of Flash memory.
|
|
|
|
- CFG_MONITOR_BASE:
|
|
Physical start address of boot monitor code (set by
|
|
make config files to be same as the text base address
|
|
(TEXT_BASE) used when linking) - same as
|
|
CFG_FLASH_BASE when booting from flash.
|
|
|
|
- CFG_MONITOR_LEN:
|
|
Size of memory reserved for monitor code
|
|
|
|
- CFG_MALLOC_LEN:
|
|
Size of DRAM reserved for malloc() use.
|
|
|
|
- CFG_BOOTMAPSZ:
|
|
Maximum size of memory mapped by the startup code of
|
|
the Linux kernel; all data that must be processed by
|
|
the Linux kernel (bd_info, boot arguments, eventually
|
|
initrd image) must be put below this limit.
|
|
|
|
- CFG_MAX_FLASH_BANKS:
|
|
Max number of Flash memory banks
|
|
|
|
- CFG_MAX_FLASH_SECT:
|
|
Max number of sectors on a Flash chip
|
|
|
|
- CFG_FLASH_ERASE_TOUT:
|
|
Timeout for Flash erase operations (in ms)
|
|
|
|
- CFG_FLASH_WRITE_TOUT:
|
|
Timeout for Flash write operations (in ms)
|
|
|
|
- CFG_DIRECT_FLASH_TFTP:
|
|
|
|
Enable TFTP transfers directly to flash memory;
|
|
without this option such a download has to be
|
|
performed in two steps: (1) download to RAM, and (2)
|
|
copy from RAM to flash.
|
|
|
|
The two-step approach is usually more reliable, since
|
|
you can check if the download worked before you erase
|
|
the flash, but in some situations (when sytem RAM is
|
|
too limited to allow for a tempory copy of the
|
|
downloaded image) this option may be very useful.
|
|
|
|
- CFG_FLASH_CFI:
|
|
Define if the flash driver uses extra elements in the
|
|
common flash structure for storing flash geometry
|
|
|
|
The following definitions that deal with the placement and management
|
|
of environment data (variable area); in general, we support the
|
|
following configurations:
|
|
|
|
- CFG_ENV_IS_IN_FLASH:
|
|
|
|
Define this if the environment is in flash memory.
|
|
|
|
a) The environment occupies one whole flash sector, which is
|
|
"embedded" in the text segment with the U-Boot code. This
|
|
happens usually with "bottom boot sector" or "top boot
|
|
sector" type flash chips, which have several smaller
|
|
sectors at the start or the end. For instance, such a
|
|
layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
|
|
such a case you would place the environment in one of the
|
|
4 kB sectors - with U-Boot code before and after it. With
|
|
"top boot sector" type flash chips, you would put the
|
|
environment in one of the last sectors, leaving a gap
|
|
between U-Boot and the environment.
|
|
|
|
- CFG_ENV_OFFSET:
|
|
|
|
Offset of environment data (variable area) to the
|
|
beginning of flash memory; for instance, with bottom boot
|
|
type flash chips the second sector can be used: the offset
|
|
for this sector is given here.
|
|
|
|
CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
|
|
|
|
- CFG_ENV_ADDR:
|
|
|
|
This is just another way to specify the start address of
|
|
the flash sector containing the environment (instead of
|
|
CFG_ENV_OFFSET).
|
|
|
|
- CFG_ENV_SECT_SIZE:
|
|
|
|
Size of the sector containing the environment.
|
|
|
|
|
|
b) Sometimes flash chips have few, equal sized, BIG sectors.
|
|
In such a case you don't want to spend a whole sector for
|
|
the environment.
|
|
|
|
- CFG_ENV_SIZE:
|
|
|
|
If you use this in combination with CFG_ENV_IS_IN_FLASH
|
|
and CFG_ENV_SECT_SIZE, you can specify to use only a part
|
|
of this flash sector for the environment. This saves
|
|
memory for the RAM copy of the environment.
|
|
|
|
It may also save flash memory if you decide to use this
|
|
when your environment is "embedded" within U-Boot code,
|
|
since then the remainder of the flash sector could be used
|
|
for U-Boot code. It should be pointed out that this is
|
|
STRONGLY DISCOURAGED from a robustness point of view:
|
|
updating the environment in flash makes it always
|
|
necessary to erase the WHOLE sector. If something goes
|
|
wrong before the contents has been restored from a copy in
|
|
RAM, your target system will be dead.
|
|
|
|
- CFG_ENV_ADDR_REDUND
|
|
CFG_ENV_SIZE_REDUND
|
|
|
|
These settings describe a second storage area used to hold
|
|
a redundand copy of the environment data, so that there is
|
|
a valid backup copy in case there is a power failure during
|
|
a "saveenv" operation.
|
|
|
|
BE CAREFUL! Any changes to the flash layout, and some changes to the
|
|
source code will make it necessary to adapt <board>/u-boot.lds*
|
|
accordingly!
|
|
|
|
|
|
- CFG_ENV_IS_IN_NVRAM:
|
|
|
|
Define this if you have some non-volatile memory device
|
|
(NVRAM, battery buffered SRAM) which you want to use for the
|
|
environment.
|
|
|
|
- CFG_ENV_ADDR:
|
|
- CFG_ENV_SIZE:
|
|
|
|
These two #defines are used to determin the memory area you
|
|
want to use for environment. It is assumed that this memory
|
|
can just be read and written to, without any special
|
|
provision.
|
|
|
|
BE CAREFUL! The first access to the environment happens quite early
|
|
in U-Boot initalization (when we try to get the setting of for the
|
|
console baudrate). You *MUST* have mappend your NVRAM area then, or
|
|
U-Boot will hang.
|
|
|
|
Please note that even with NVRAM we still use a copy of the
|
|
environment in RAM: we could work on NVRAM directly, but we want to
|
|
keep settings there always unmodified except somebody uses "saveenv"
|
|
to save the current settings.
|
|
|
|
|
|
- CFG_ENV_IS_IN_EEPROM:
|
|
|
|
Use this if you have an EEPROM or similar serial access
|
|
device and a driver for it.
|
|
|
|
- CFG_ENV_OFFSET:
|
|
- CFG_ENV_SIZE:
|
|
|
|
These two #defines specify the offset and size of the
|
|
environment area within the total memory of your EEPROM.
|
|
|
|
- CFG_I2C_EEPROM_ADDR:
|
|
If defined, specified the chip address of the EEPROM device.
|
|
The default address is zero.
|
|
|
|
- CFG_EEPROM_PAGE_WRITE_BITS:
|
|
If defined, the number of bits used to address bytes in a
|
|
single page in the EEPROM device. A 64 byte page, for example
|
|
would require six bits.
|
|
|
|
- CFG_EEPROM_PAGE_WRITE_DELAY_MS:
|
|
If defined, the number of milliseconds to delay between
|
|
page writes. The default is zero milliseconds.
|
|
|
|
- CFG_I2C_EEPROM_ADDR_LEN:
|
|
The length in bytes of the EEPROM memory array address. Note
|
|
that this is NOT the chip address length!
|
|
|
|
- CFG_EEPROM_SIZE:
|
|
The size in bytes of the EEPROM device.
|
|
|
|
|
|
- CFG_SPI_INIT_OFFSET
|
|
|
|
Defines offset to the initial SPI buffer area in DPRAM. The
|
|
area is used at an early stage (ROM part) if the environment
|
|
is configured to reside in the SPI EEPROM: We need a 520 byte
|
|
scratch DPRAM area. It is used between the two initialization
|
|
calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
|
|
to be a good choice since it makes it far enough from the
|
|
start of the data area as well as from the stack pointer.
|
|
|
|
Please note that the environment is read-only as long as the monitor
|
|
has been relocated to RAM and a RAM copy of the environment has been
|
|
created; also, when using EEPROM you will have to use getenv_r()
|
|
until then to read environment variables.
|
|
|
|
The environment is protected by a CRC32 checksum. Before the monitor
|
|
is relocated into RAM, as a result of a bad CRC you will be working
|
|
with the compiled-in default environment - *silently*!!! [This is
|
|
necessary, because the first environment variable we need is the
|
|
"baudrate" setting for the console - if we have a bad CRC, we don't
|
|
have any device yet where we could complain.]
|
|
|
|
Note: once the monitor has been relocated, then it will complain if
|
|
the default environment is used; a new CRC is computed as soon as you
|
|
use the "saveenv" command to store a valid environment.
|
|
|
|
|
|
Low Level (hardware related) configuration options:
|
|
---------------------------------------------------
|
|
|
|
- CFG_CACHELINE_SIZE:
|
|
Cache Line Size of the CPU.
|
|
|
|
- CFG_DEFAULT_IMMR:
|
|
Default address of the IMMR after system reset.
|
|
Needed on some 8260 systems (MPC8260ADS and RPXsuper)
|
|
to be able to adjust the position of the IMMR
|
|
register after a reset.
|
|
|
|
- Floppy Disk Support:
|
|
CFG_FDC_DRIVE_NUMBER
|
|
|
|
the default drive number (default value 0)
|
|
|
|
CFG_ISA_IO_STRIDE
|
|
|
|
defines the spacing between fdc chipset registers
|
|
(default value 1)
|
|
|
|
CFG_ISA_IO_OFFSET
|
|
|
|
defines the offset of register from address. It
|
|
depends on which part of the data bus is connected to
|
|
the fdc chipset. (default value 0)
|
|
|
|
If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
|
|
CFG_FDC_DRIVE_NUMBER are undefined, they take their
|
|
default value.
|
|
|
|
if CFG_FDC_HW_INIT is defined, then the function
|
|
fdc_hw_init() is called at the beginning of the FDC
|
|
setup. fdc_hw_init() must be provided by the board
|
|
source code. It is used to make hardware dependant
|
|
initializations.
|
|
|
|
- CFG_IMMR: Physical address of the Internal Memory Mapped
|
|
Register; DO NOT CHANGE! (11-4)
|
|
[MPC8xx systems only]
|
|
|
|
- CFG_INIT_RAM_ADDR:
|
|
|
|
Start address of memory area tha can be used for
|
|
initial data and stack; please note that this must be
|
|
writable memory that is working WITHOUT special
|
|
initialization, i. e. you CANNOT use normal RAM which
|
|
will become available only after programming the
|
|
memory controller and running certain initialization
|
|
sequences.
|
|
|
|
U-Boot uses the following memory types:
|
|
- MPC8xx and MPC8260: IMMR (internal memory of the CPU)
|
|
- MPC824X: data cache
|
|
- PPC4xx: data cache
|
|
|
|
- CFG_GBL_DATA_OFFSET:
|
|
|
|
Offset of the initial data structure in the memory
|
|
area defined by CFG_INIT_RAM_ADDR. Usually
|
|
CFG_GBL_DATA_OFFSET is chosen such that the initial
|
|
data is located at the end of the available space
|
|
(sometimes written as (CFG_INIT_RAM_END -
|
|
CFG_INIT_DATA_SIZE), and the initial stack is just
|
|
below that area (growing from (CFG_INIT_RAM_ADDR +
|
|
CFG_GBL_DATA_OFFSET) downward.
|
|
|
|
Note:
|
|
On the MPC824X (or other systems that use the data
|
|
cache for initial memory) the address chosen for
|
|
CFG_INIT_RAM_ADDR is basically arbitrary - it must
|
|
point to an otherwise UNUSED address space between
|
|
the top of RAM and the start of the PCI space.
|
|
|
|
- CFG_SIUMCR: SIU Module Configuration (11-6)
|
|
|
|
- CFG_SYPCR: System Protection Control (11-9)
|
|
|
|
- CFG_TBSCR: Time Base Status and Control (11-26)
|
|
|
|
- CFG_PISCR: Periodic Interrupt Status and Control (11-31)
|
|
|
|
- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
|
|
|
|
- CFG_SCCR: System Clock and reset Control Register (15-27)
|
|
|
|
- CFG_OR_TIMING_SDRAM:
|
|
SDRAM timing
|
|
|
|
- CFG_MAMR_PTA:
|
|
periodic timer for refresh
|
|
|
|
- CFG_DER: Debug Event Register (37-47)
|
|
|
|
- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
|
|
CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
|
|
CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
|
|
CFG_BR1_PRELIM:
|
|
Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
|
|
|
|
- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
|
|
CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
|
|
CFG_OR3_PRELIM, CFG_BR3_PRELIM:
|
|
Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
|
|
|
|
- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
|
|
CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
|
|
Machine Mode Register and Memory Periodic Timer
|
|
Prescaler definitions (SDRAM timing)
|
|
|
|
- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
|
|
enable I2C microcode relocation patch (MPC8xx);
|
|
define relocation offset in DPRAM [DSP2]
|
|
|
|
- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
|
|
enable SPI microcode relocation patch (MPC8xx);
|
|
define relocation offset in DPRAM [SCC4]
|
|
|
|
- CFG_USE_OSCCLK:
|
|
Use OSCM clock mode on MBX8xx board. Be careful,
|
|
wrong setting might damage your board. Read
|
|
doc/README.MBX before setting this variable!
|
|
|
|
- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
|
|
Offset of the bootmode word in DPRAM used by post
|
|
(Power On Self Tests). This definition overrides
|
|
#define'd default value in commproc.h resp.
|
|
cpm_8260.h.
|
|
|
|
- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
|
|
CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
|
|
CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
|
|
CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
|
|
CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
|
|
CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
|
|
CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
|
|
CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
|
|
Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
|
|
|
|
Building the Software:
|
|
======================
|
|
|
|
Building U-Boot has been tested in native PPC environments (on a
|
|
PowerBook G3 running LinuxPPC 2000) and in cross environments
|
|
(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
|
|
NetBSD 1.5 on x86).
|
|
|
|
If you are not using a native PPC environment, it is assumed that you
|
|
have the GNU cross compiling tools available in your path and named
|
|
with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
|
|
you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
|
|
the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
|
|
change it to:
|
|
|
|
CROSS_COMPILE = ppc_4xx-
|
|
|
|
|
|
U-Boot is intended to be simple to build. After installing the
|
|
sources you must configure U-Boot for one specific board type. This
|
|
is done by typing:
|
|
|
|
make NAME_config
|
|
|
|
where "NAME_config" is the name of one of the existing
|
|
configurations; the following names are supported:
|
|
|
|
ADCIOP_config GTH_config TQM850L_config
|
|
ADS860_config IP860_config TQM855L_config
|
|
AR405_config IVML24_config TQM860L_config
|
|
CANBT_config IVMS8_config WALNUT405_config
|
|
CPCI405_config LANTEC_config cogent_common_config
|
|
CPCIISER4_config MBX_config cogent_mpc8260_config
|
|
CU824_config MBX860T_config cogent_mpc8xx_config
|
|
ESTEEM192E_config RPXlite_config hermes_config
|
|
ETX094_config RPXsuper_config hymod_config
|
|
FADS823_config SM850_config lwmon_config
|
|
FADS850SAR_config SPD823TS_config pcu_e_config
|
|
FADS860T_config SXNI855T_config rsdproto_config
|
|
FPS850L_config Sandpoint8240_config sbc8260_config
|
|
GENIETV_config TQM823L_config PIP405_config
|
|
GEN860T_config EBONY_config FPS860L_config
|
|
ELPT860_config cmi_mpc5xx_config NETVIA_config
|
|
|
|
Note: for some board special configuration names may exist; check if
|
|
additional information is available from the board vendor; for
|
|
instance, the TQM8xxL systems run normally at 50 MHz and use a
|
|
SCC for 10baseT ethernet; there are also systems with 80 MHz
|
|
CPU clock, and an optional Fast Ethernet module is available
|
|
for CPU's with FEC. You can select such additional "features"
|
|
when chosing the configuration, i. e.
|
|
|
|
make TQM860L_config
|
|
- will configure for a plain TQM860L, i. e. 50MHz, no FEC
|
|
|
|
make TQM860L_FEC_config
|
|
- will configure for a TQM860L at 50MHz with FEC for ethernet
|
|
|
|
make TQM860L_80MHz_config
|
|
- will configure for a TQM860L at 80 MHz, with normal 10baseT
|
|
interface
|
|
|
|
make TQM860L_FEC_80MHz_config
|
|
- will configure for a TQM860L at 80 MHz with FEC for ethernet
|
|
|
|
make TQM823L_LCD_config
|
|
- will configure for a TQM823L with U-Boot console on LCD
|
|
|
|
make TQM823L_LCD_80MHz_config
|
|
- will configure for a TQM823L at 80 MHz with U-Boot console on LCD
|
|
|
|
etc.
|
|
|
|
|
|
|
|
Finally, type "make all", and you should get some working U-Boot
|
|
images ready for downlod to / installation on your system:
|
|
|
|
- "u-boot.bin" is a raw binary image
|
|
- "u-boot" is an image in ELF binary format
|
|
- "u-boot.srec" is in Motorola S-Record format
|
|
|
|
|
|
Please be aware that the Makefiles assume you are using GNU make, so
|
|
for instance on NetBSD you might need to use "gmake" instead of
|
|
native "make".
|
|
|
|
|
|
If the system board that you have is not listed, then you will need
|
|
to port U-Boot to your hardware platform. To do this, follow these
|
|
steps:
|
|
|
|
1. Add a new configuration option for your board to the toplevel
|
|
"Makefile" and to the "MAKEALL" script, using the existing
|
|
entries as examples. Note that here and at many other places
|
|
boards and other names are listed alphabetically sorted. Please
|
|
keep this order.
|
|
2. Create a new directory to hold your board specific code. Add any
|
|
files you need. In your board directory, you will need at least
|
|
the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
|
|
3. Create a new configuration file "include/configs/<board>.h" for
|
|
your board
|
|
3. If you're porting U-Boot to a new CPU, then also create a new
|
|
directory to hold your CPU specific code. Add any files you need.
|
|
4. Run "make <board>_config" with your new name.
|
|
5. Type "make", and you should get a working "u-boot.srec" file
|
|
to be installed on your target system.
|
|
6. Debug and solve any problems that might arise.
|
|
[Of course, this last step is much harder than it sounds.]
|
|
|
|
|
|
Testing of U-Boot Modifications, Ports to New Hardware, etc.:
|
|
==============================================================
|
|
|
|
If you have modified U-Boot sources (for instance added a new board
|
|
or support for new devices, a new CPU, etc.) you are expected to
|
|
provide feedback to the other developers. The feedback normally takes
|
|
the form of a "patch", i. e. a context diff against a certain (latest
|
|
official or latest in CVS) version of U-Boot sources.
|
|
|
|
But before you submit such a patch, please verify that your modifi-
|
|
cation did not break existing code. At least make sure that *ALL* of
|
|
the supported boards compile WITHOUT ANY compiler warnings. To do so,
|
|
just run the "MAKEALL" script, which will configure and build U-Boot
|
|
for ALL supported system. Be warned, this will take a while. You can
|
|
select which (cross) compiler to use py passing a `CROSS_COMPILE'
|
|
environment variable to the script, i. e. to use the cross tools from
|
|
MontaVista's Hard Hat Linux you can type
|
|
|
|
CROSS_COMPILE=ppc_8xx- MAKEALL
|
|
|
|
or to build on a native PowerPC system you can type
|
|
|
|
CROSS_COMPILE=' ' MAKEALL
|
|
|
|
See also "U-Boot Porting Guide" below.
|
|
|
|
|
|
|
|
Monitor Commands - Overview:
|
|
============================
|
|
|
|
go - start application at address 'addr'
|
|
run - run commands in an environment variable
|
|
bootm - boot application image from memory
|
|
bootp - boot image via network using BootP/TFTP protocol
|
|
tftpboot- boot image via network using TFTP protocol
|
|
and env variables "ipaddr" and "serverip"
|
|
(and eventually "gatewayip")
|
|
rarpboot- boot image via network using RARP/TFTP protocol
|
|
diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
|
|
loads - load S-Record file over serial line
|
|
loadb - load binary file over serial line (kermit mode)
|
|
md - memory display
|
|
mm - memory modify (auto-incrementing)
|
|
nm - memory modify (constant address)
|
|
mw - memory write (fill)
|
|
cp - memory copy
|
|
cmp - memory compare
|
|
crc32 - checksum calculation
|
|
imd - i2c memory display
|
|
imm - i2c memory modify (auto-incrementing)
|
|
inm - i2c memory modify (constant address)
|
|
imw - i2c memory write (fill)
|
|
icrc32 - i2c checksum calculation
|
|
iprobe - probe to discover valid I2C chip addresses
|
|
iloop - infinite loop on address range
|
|
isdram - print SDRAM configuration information
|
|
sspi - SPI utility commands
|
|
base - print or set address offset
|
|
printenv- print environment variables
|
|
setenv - set environment variables
|
|
saveenv - save environment variables to persistent storage
|
|
protect - enable or disable FLASH write protection
|
|
erase - erase FLASH memory
|
|
flinfo - print FLASH memory information
|
|
bdinfo - print Board Info structure
|
|
iminfo - print header information for application image
|
|
coninfo - print console devices and informations
|
|
ide - IDE sub-system
|
|
loop - infinite loop on address range
|
|
mtest - simple RAM test
|
|
icache - enable or disable instruction cache
|
|
dcache - enable or disable data cache
|
|
reset - Perform RESET of the CPU
|
|
echo - echo args to console
|
|
version - print monitor version
|
|
help - print online help
|
|
? - alias for 'help'
|
|
|
|
|
|
Monitor Commands - Detailed Description:
|
|
========================================
|
|
|
|
TODO.
|
|
|
|
For now: just type "help <command>".
|
|
|
|
|
|
Environment Variables:
|
|
======================
|
|
|
|
U-Boot supports user configuration using Environment Variables which
|
|
can be made persistent by saving to Flash memory.
|
|
|
|
Environment Variables are set using "setenv", printed using
|
|
"printenv", and saved to Flash using "saveenv". Using "setenv"
|
|
without a value can be used to delete a variable from the
|
|
environment. As long as you don't save the environment you are
|
|
working with an in-memory copy. In case the Flash area containing the
|
|
environment is erased by accident, a default environment is provided.
|
|
|
|
Some configuration options can be set using Environment Variables:
|
|
|
|
baudrate - see CONFIG_BAUDRATE
|
|
|
|
bootdelay - see CONFIG_BOOTDELAY
|
|
|
|
bootcmd - see CONFIG_BOOTCOMMAND
|
|
|
|
bootargs - Boot arguments when booting an RTOS image
|
|
|
|
bootfile - Name of the image to load with TFTP
|
|
|
|
autoload - if set to "no" (any string beginning with 'n'),
|
|
"bootp" will just load perform a lookup of the
|
|
configuration from the BOOTP server, but not try to
|
|
load any image using TFTP
|
|
|
|
autostart - if set to "yes", an image loaded using the "bootp",
|
|
"rarpboot", "tftpboot" or "diskboot" commands will
|
|
be automatically started (by internally calling
|
|
"bootm")
|
|
|
|
If set to "no", a standalone image passed to the
|
|
"bootm" command will be copied to the load address
|
|
(and eventually uncompressed), but NOT be started.
|
|
This can be used to load and uncompress arbitrary
|
|
data.
|
|
|
|
initrd_high - restrict positioning of initrd images:
|
|
If this variable is not set, initrd images will be
|
|
copied to the highest possible address in RAM; this
|
|
is usually what you want since it allows for
|
|
maximum initrd size. If for some reason you want to
|
|
make sure that the initrd image is loaded below the
|
|
CFG_BOOTMAPSZ limit, you can set this environment
|
|
variable to a value of "no" or "off" or "0".
|
|
Alternatively, you can set it to a maximum upper
|
|
address to use (U-Boot will still check that it
|
|
does not overwrite the U-Boot stack and data).
|
|
|
|
For instance, when you have a system with 16 MB
|
|
RAM, and want to reseve 4 MB from use by Linux,
|
|
you can do this by adding "mem=12M" to the value of
|
|
the "bootargs" variable. However, now you must make
|
|
sure, that the initrd image is placed in the first
|
|
12 MB as well - this can be done with
|
|
|
|
setenv initrd_high 00c00000
|
|
|
|
ipaddr - IP address; needed for tftpboot command
|
|
|
|
loadaddr - Default load address for commands like "bootp",
|
|
"rarpboot", "tftpboot", "loadb" or "diskboot"
|
|
|
|
loads_echo - see CONFIG_LOADS_ECHO
|
|
|
|
serverip - TFTP server IP address; needed for tftpboot command
|
|
|
|
bootretry - see CONFIG_BOOT_RETRY_TIME
|
|
|
|
bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
|
|
|
|
bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
|
|
|
|
|
|
The following environment variables may be used and automatically
|
|
updated by the network boot commands ("bootp" and "rarpboot"),
|
|
depending the information provided by your boot server:
|
|
|
|
bootfile - see above
|
|
dnsip - IP address of your Domain Name Server
|
|
gatewayip - IP address of the Gateway (Router) to use
|
|
hostname - Target hostname
|
|
ipaddr - see above
|
|
netmask - Subnet Mask
|
|
rootpath - Pathname of the root filesystem on the NFS server
|
|
serverip - see above
|
|
|
|
|
|
There are two special Environment Variables:
|
|
|
|
serial# - contains hardware identification information such
|
|
as type string and/or serial number
|
|
ethaddr - Ethernet address
|
|
|
|
These variables can be set only once (usually during manufacturing of
|
|
the board). U-Boot refuses to delete or overwrite these variables
|
|
once they have been set once.
|
|
|
|
|
|
Further special Environment Variables:
|
|
|
|
ver - Contains the U-Boot version string as printed
|
|
with the "version" command. This variable is
|
|
readonly (see CONFIG_VERSION_VARIABLE).
|
|
|
|
|
|
Please note that changes to some configuration parameters may take
|
|
only effect after the next boot (yes, that's just like Windoze :-).
|
|
|
|
|
|
Note for Redundant Ethernet Interfaces:
|
|
=======================================
|
|
|
|
Some boards come with redundand ethernet interfaces; U-Boot supports
|
|
such configurations and is capable of automatic selection of a
|
|
"working" interface when needed. MAC assignemnt works as follows:
|
|
|
|
Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
|
|
MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
|
|
"eth1addr" (=>eth1), "eth2addr", ...
|
|
|
|
If the network interface stores some valid MAC address (for instance
|
|
in SROM), this is used as default address if there is NO correspon-
|
|
ding setting in the environment; if the corresponding environment
|
|
variable is set, this overrides the settings in the card; that means:
|
|
|
|
o If the SROM has a valid MAC address, and there is no address in the
|
|
environment, the SROM's address is used.
|
|
|
|
o If there is no valid address in the SROM, and a definition in the
|
|
environment exists, then the value from the environment variable is
|
|
used.
|
|
|
|
o If both the SROM and the environment contain a MAC address, and
|
|
both addresses are the same, this MAC address is used.
|
|
|
|
o If both the SROM and the environment contain a MAC address, and the
|
|
addresses differ, the value from the environment is used and a
|
|
warning is printed.
|
|
|
|
o If neither SROM nor the environment contain a MAC address, an error
|
|
is raised.
|
|
|
|
|
|
|
|
Image Formats:
|
|
==============
|
|
|
|
The "boot" commands of this monitor operate on "image" files which
|
|
can be basicly anything, preceeded by a special header; see the
|
|
definitions in include/image.h for details; basicly, the header
|
|
defines the following image properties:
|
|
|
|
* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
|
|
4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
|
|
LynxOS, pSOS, QNX, RTEMS, ARTOS;
|
|
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS).
|
|
* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
|
|
IA64, MIPS, MIPS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
|
|
Currently supported: PowerPC).
|
|
* Compression Type (Provisions for uncompressed, gzip, bzip2;
|
|
Currently supported: uncompressed, gzip).
|
|
* Load Address
|
|
* Entry Point
|
|
* Image Name
|
|
* Image Timestamp
|
|
|
|
The header is marked by a special Magic Number, and both the header
|
|
and the data portions of the image are secured against corruption by
|
|
CRC32 checksums.
|
|
|
|
|
|
Linux Support:
|
|
==============
|
|
|
|
Although U-Boot should support any OS or standalone application
|
|
easily, Linux has always been in the focus during the design of
|
|
U-Boot.
|
|
|
|
U-Boot includes many features that so far have been part of some
|
|
special "boot loader" code within the Linux kernel. Also, any
|
|
"initrd" images to be used are no longer part of one big Linux image;
|
|
instead, kernel and "initrd" are separate images. This implementation
|
|
serves serveral purposes:
|
|
|
|
- the same features can be used for other OS or standalone
|
|
applications (for instance: using compressed images to reduce the
|
|
Flash memory footprint)
|
|
|
|
- it becomes much easier to port new Linux kernel versions because
|
|
lots of low-level, hardware dependend stuff are done by U-Boot
|
|
|
|
- the same Linux kernel image can now be used with different "initrd"
|
|
images; of course this also means that different kernel images can
|
|
be run with the same "initrd". This makes testing easier (you don't
|
|
have to build a new "zImage.initrd" Linux image when you just
|
|
change a file in your "initrd"). Also, a field-upgrade of the
|
|
software is easier now.
|
|
|
|
|
|
Linux HOWTO:
|
|
============
|
|
|
|
Porting Linux to U-Boot based systems:
|
|
---------------------------------------
|
|
|
|
U-Boot cannot save you from doing all the necessary modifications to
|
|
configure the Linux device drivers for use with your target hardware
|
|
(no, we don't intend to provide a full virtual machine interface to
|
|
Linux :-).
|
|
|
|
But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
|
|
|
|
Just make sure your machine specific header file (for instance
|
|
include/asm-ppc/tqm8xx.h) includes the same definition of the Board
|
|
Information structure as we define in include/u-boot.h, and make
|
|
sure that your definition of IMAP_ADDR uses the same value as your
|
|
U-Boot configuration in CFG_IMMR.
|
|
|
|
|
|
Configuring the Linux kernel:
|
|
-----------------------------
|
|
|
|
No specific requirements for U-Boot. Make sure you have some root
|
|
device (initial ramdisk, NFS) for your target system.
|
|
|
|
|
|
Building a Linux Image:
|
|
-----------------------
|
|
|
|
With U-Boot, "normal" build targets like "zImage" or "bzImage" are
|
|
not used. If you use recent kernel source, a new build target
|
|
"uImage" will exist which automatically builds an image usable by
|
|
U-Boot. Most older kernels also have support for a "pImage" target,
|
|
which was introduced for our predecessor project PPCBoot and uses a
|
|
100% compatible format.
|
|
|
|
Example:
|
|
|
|
make TQM850L_config
|
|
make oldconfig
|
|
make dep
|
|
make uImage
|
|
|
|
The "uImage" build target uses a special tool (in 'tools/mkimage') to
|
|
encapsulate a compressed Linux kernel image with header information,
|
|
CRC32 checksum etc. for use with U-Boot. This is what we are doing:
|
|
|
|
* build a standard "vmlinux" kernel image (in ELF binary format):
|
|
|
|
* convert the kernel into a raw binary image:
|
|
|
|
${CROSS_COMPILE}-objcopy -O binary \
|
|
-R .note -R .comment \
|
|
-S vmlinux linux.bin
|
|
|
|
* compress the binary image:
|
|
|
|
gzip -9 linux.bin
|
|
|
|
* package compressed binary image for U-Boot:
|
|
|
|
mkimage -A ppc -O linux -T kernel -C gzip \
|
|
-a 0 -e 0 -n "Linux Kernel Image" \
|
|
-d linux.bin.gz uImage
|
|
|
|
|
|
The "mkimage" tool can also be used to create ramdisk images for use
|
|
with U-Boot, either separated from the Linux kernel image, or
|
|
combined into one file. "mkimage" encapsulates the images with a 64
|
|
byte header containing information about target architecture,
|
|
operating system, image type, compression method, entry points, time
|
|
stamp, CRC32 checksums, etc.
|
|
|
|
"mkimage" can be called in two ways: to verify existing images and
|
|
print the header information, or to build new images.
|
|
|
|
In the first form (with "-l" option) mkimage lists the information
|
|
contained in the header of an existing U-Boot image; this includes
|
|
checksum verification:
|
|
|
|
tools/mkimage -l image
|
|
-l ==> list image header information
|
|
|
|
The second form (with "-d" option) is used to build a U-Boot image
|
|
from a "data file" which is used as image payload:
|
|
|
|
tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
|
|
-n name -d data_file image
|
|
-A ==> set architecture to 'arch'
|
|
-O ==> set operating system to 'os'
|
|
-T ==> set image type to 'type'
|
|
-C ==> set compression type 'comp'
|
|
-a ==> set load address to 'addr' (hex)
|
|
-e ==> set entry point to 'ep' (hex)
|
|
-n ==> set image name to 'name'
|
|
-d ==> use image data from 'datafile'
|
|
|
|
Right now, all Linux kernels use the same load address (0x00000000),
|
|
but the entry point address depends on the kernel version:
|
|
|
|
- 2.2.x kernels have the entry point at 0x0000000C,
|
|
- 2.3.x and later kernels have the entry point at 0x00000000.
|
|
|
|
So a typical call to build a U-Boot image would read:
|
|
|
|
-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
|
|
> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
|
|
> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
|
|
> examples/uImage.TQM850L
|
|
Image Name: 2.4.4 kernel for TQM850L
|
|
Created: Wed Jul 19 02:34:59 2000
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
|
|
Load Address: 0x00000000
|
|
Entry Point: 0x00000000
|
|
|
|
To verify the contents of the image (or check for corruption):
|
|
|
|
-> tools/mkimage -l examples/uImage.TQM850L
|
|
Image Name: 2.4.4 kernel for TQM850L
|
|
Created: Wed Jul 19 02:34:59 2000
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
|
|
Load Address: 0x00000000
|
|
Entry Point: 0x00000000
|
|
|
|
NOTE: for embedded systems where boot time is critical you can trade
|
|
speed for memory and install an UNCOMPRESSED image instead: this
|
|
needs more space in Flash, but boots much faster since it does not
|
|
need to be uncompressed:
|
|
|
|
-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
|
|
-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
|
|
> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
|
|
> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
|
|
> examples/uImage.TQM850L-uncompressed
|
|
Image Name: 2.4.4 kernel for TQM850L
|
|
Created: Wed Jul 19 02:34:59 2000
|
|
Image Type: PowerPC Linux Kernel Image (uncompressed)
|
|
Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
|
|
Load Address: 0x00000000
|
|
Entry Point: 0x00000000
|
|
|
|
|
|
Similar you can build U-Boot images from a 'ramdisk.image.gz' file
|
|
when your kernel is intended to use an initial ramdisk:
|
|
|
|
-> tools/mkimage -n 'Simple Ramdisk Image' \
|
|
> -A ppc -O linux -T ramdisk -C gzip \
|
|
> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
|
|
Image Name: Simple Ramdisk Image
|
|
Created: Wed Jan 12 14:01:50 2000
|
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
|
Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
|
|
Load Address: 0x00000000
|
|
Entry Point: 0x00000000
|
|
|
|
|
|
Installing a Linux Image:
|
|
-------------------------
|
|
|
|
To downloading a U-Boot image over the serial (console) interface,
|
|
you must convert the image to S-Record format:
|
|
|
|
objcopy -I binary -O srec examples/image examples/image.srec
|
|
|
|
The 'objcopy' does not understand the information in the U-Boot
|
|
image header, so the resulting S-Record file will be relative to
|
|
address 0x00000000. To load it to a given address, you need to
|
|
specify the target address as 'offset' parameter with the 'loads'
|
|
command.
|
|
|
|
Example: install the image to address 0x40100000 (which on the
|
|
TQM8xxL is in the first Flash bank):
|
|
|
|
=> erase 40100000 401FFFFF
|
|
|
|
.......... done
|
|
Erased 8 sectors
|
|
|
|
=> loads 40100000
|
|
## Ready for S-Record download ...
|
|
~>examples/image.srec
|
|
1 2 3 4 5 6 7 8 9 10 11 12 13 ...
|
|
...
|
|
15989 15990 15991 15992
|
|
[file transfer complete]
|
|
[connected]
|
|
## Start Addr = 0x00000000
|
|
|
|
|
|
You can check the success of the download using the 'iminfo' command;
|
|
this includes a checksum verification so you can be sure no data
|
|
corruption happened:
|
|
|
|
=> imi 40100000
|
|
|
|
## Checking Image at 40100000 ...
|
|
Image Name: 2.2.13 for initrd on TQM850L
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 0000000c
|
|
Verifying Checksum ... OK
|
|
|
|
|
|
|
|
Boot Linux:
|
|
-----------
|
|
|
|
The "bootm" command is used to boot an application that is stored in
|
|
memory (RAM or Flash). In case of a Linux kernel image, the contents
|
|
of the "bootargs" environment variable is passed to the kernel as
|
|
parameters. You can check and modify this variable using the
|
|
"printenv" and "setenv" commands:
|
|
|
|
|
|
=> printenv bootargs
|
|
bootargs=root=/dev/ram
|
|
|
|
=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
|
|
|
=> printenv bootargs
|
|
bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
|
|
|
=> bootm 40020000
|
|
## Booting Linux kernel at 40020000 ...
|
|
Image Name: 2.2.13 for NFS on TQM850L
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 381681 Bytes = 372 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 0000000c
|
|
Verifying Checksum ... OK
|
|
Uncompressing Kernel Image ... OK
|
|
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
|
|
Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
|
time_init: decrementer frequency = 187500000/60
|
|
Calibrating delay loop... 49.77 BogoMIPS
|
|
Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
|
|
...
|
|
|
|
If you want to boot a Linux kernel with initial ram disk, you pass
|
|
the memory addreses of both the kernel and the initrd image (PPBCOOT
|
|
format!) to the "bootm" command:
|
|
|
|
=> imi 40100000 40200000
|
|
|
|
## Checking Image at 40100000 ...
|
|
Image Name: 2.2.13 for initrd on TQM850L
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 0000000c
|
|
Verifying Checksum ... OK
|
|
|
|
## Checking Image at 40200000 ...
|
|
Image Name: Simple Ramdisk Image
|
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
|
Data Size: 566530 Bytes = 553 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 00000000
|
|
Verifying Checksum ... OK
|
|
|
|
=> bootm 40100000 40200000
|
|
## Booting Linux kernel at 40100000 ...
|
|
Image Name: 2.2.13 for initrd on TQM850L
|
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 0000000c
|
|
Verifying Checksum ... OK
|
|
Uncompressing Kernel Image ... OK
|
|
## Loading RAMDisk Image at 40200000 ...
|
|
Image Name: Simple Ramdisk Image
|
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
|
Data Size: 566530 Bytes = 553 kB = 0 MB
|
|
Load Address: 00000000
|
|
Entry Point: 00000000
|
|
Verifying Checksum ... OK
|
|
Loading Ramdisk ... OK
|
|
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
|
|
Boot arguments: root=/dev/ram
|
|
time_init: decrementer frequency = 187500000/60
|
|
Calibrating delay loop... 49.77 BogoMIPS
|
|
...
|
|
RAMDISK: Compressed image found at block 0
|
|
VFS: Mounted root (ext2 filesystem).
|
|
|
|
bash#
|
|
|
|
More About U-Boot Image Types:
|
|
------------------------------
|
|
|
|
U-Boot supports the following image types:
|
|
|
|
"Standalone Programs" are directly runnable in the environment
|
|
provided by U-Boot; it is expected that (if they behave
|
|
well) you can continue to work in U-Boot after return from
|
|
the Standalone Program.
|
|
"OS Kernel Images" are usually images of some Embedded OS which
|
|
will take over control completely. Usually these programs
|
|
will install their own set of exception handlers, device
|
|
drivers, set up the MMU, etc. - this means, that you cannot
|
|
expect to re-enter U-Boot except by resetting the CPU.
|
|
"RAMDisk Images" are more or less just data blocks, and their
|
|
parameters (address, size) are passed to an OS kernel that is
|
|
being started.
|
|
"Multi-File Images" contain several images, typically an OS
|
|
(Linux) kernel image and one or more data images like
|
|
RAMDisks. This construct is useful for instance when you want
|
|
to boot over the network using BOOTP etc., where the boot
|
|
server provides just a single image file, but you want to get
|
|
for instance an OS kernel and a RAMDisk image.
|
|
|
|
"Multi-File Images" start with a list of image sizes, each
|
|
image size (in bytes) specified by an "uint32_t" in network
|
|
byte order. This list is terminated by an "(uint32_t)0".
|
|
Immediately after the terminating 0 follow the images, one by
|
|
one, all aligned on "uint32_t" boundaries (size rounded up to
|
|
a multiple of 4 bytes).
|
|
|
|
"Firmware Images" are binary images containing firmware (like
|
|
U-Boot or FPGA images) which usually will be programmed to
|
|
flash memory.
|
|
|
|
"Script files" are command sequences that will be executed by
|
|
U-Boot's command interpreter; this feature is especially
|
|
useful when you configure U-Boot to use a real shell (hush)
|
|
as command interpreter.
|
|
|
|
|
|
Standalone HOWTO:
|
|
=================
|
|
|
|
One of the features of U-Boot is that you can dynamically load and
|
|
run "standalone" applications, which can use some resources of
|
|
U-Boot like console I/O functions or interrupt services.
|
|
|
|
Two simple examples are included with the sources:
|
|
|
|
"Hello World" Demo:
|
|
-------------------
|
|
|
|
'examples/hello_world.c' contains a small "Hello World" Demo
|
|
application; it is automatically compiled when you build U-Boot.
|
|
It's configured to run at address 0x00040004, so you can play with it
|
|
like that:
|
|
|
|
=> loads
|
|
## Ready for S-Record download ...
|
|
~>examples/hello_world.srec
|
|
1 2 3 4 5 6 7 8 9 10 11 ...
|
|
[file transfer complete]
|
|
[connected]
|
|
## Start Addr = 0x00040004
|
|
|
|
=> go 40004 Hello World! This is a test.
|
|
## Starting application at 0x00040004 ...
|
|
Hello World
|
|
argc = 7
|
|
argv[0] = "40004"
|
|
argv[1] = "Hello"
|
|
argv[2] = "World!"
|
|
argv[3] = "This"
|
|
argv[4] = "is"
|
|
argv[5] = "a"
|
|
argv[6] = "test."
|
|
argv[7] = "<NULL>"
|
|
Hit any key to exit ...
|
|
|
|
## Application terminated, rc = 0x0
|
|
|
|
Another example, which demonstrates how to register a CPM interrupt
|
|
handler with the U-Boot code, can be found in 'examples/timer.c'.
|
|
Here, a CPM timer is set up to generate an interrupt every second.
|
|
The interrupt service routine is trivial, just printing a '.'
|
|
character, but this is just a demo program. The application can be
|
|
controlled by the following keys:
|
|
|
|
? - print current values og the CPM Timer registers
|
|
b - enable interrupts and start timer
|
|
e - stop timer and disable interrupts
|
|
q - quit application
|
|
|
|
=> loads
|
|
## Ready for S-Record download ...
|
|
~>examples/timer.srec
|
|
1 2 3 4 5 6 7 8 9 10 11 ...
|
|
[file transfer complete]
|
|
[connected]
|
|
## Start Addr = 0x00040004
|
|
|
|
=> go 40004
|
|
## Starting application at 0x00040004 ...
|
|
TIMERS=0xfff00980
|
|
Using timer 1
|
|
tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
|
|
|
|
Hit 'b':
|
|
[q, b, e, ?] Set interval 1000000 us
|
|
Enabling timer
|
|
Hit '?':
|
|
[q, b, e, ?] ........
|
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
|
|
Hit '?':
|
|
[q, b, e, ?] .
|
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
|
|
Hit '?':
|
|
[q, b, e, ?] .
|
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
|
|
Hit '?':
|
|
[q, b, e, ?] .
|
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
|
|
Hit 'e':
|
|
[q, b, e, ?] ...Stopping timer
|
|
Hit 'q':
|
|
[q, b, e, ?] ## Application terminated, rc = 0x0
|
|
|
|
|
|
|
|
Minicom warning:
|
|
================
|
|
|
|
Over time, many people have reported problems when trying to used the
|
|
"minicom" terminal emulation program for serial download. I (wd)
|
|
consider minicom to be broken, and recommend not to use it. Under
|
|
Unix, I recommend to use CKermit for general purpose use (and
|
|
especially for kermit binary protocol download ("loadb" command), and
|
|
use "cu" for S-Record download ("loads" command).
|
|
|
|
NetBSD Notes:
|
|
=============
|
|
|
|
Starting at version 0.9.2, U-Boot supports NetBSD both as host
|
|
(build U-Boot) and target system (boots NetBSD/mpc8xx).
|
|
|
|
Building requires a cross environment; it is known to work on
|
|
NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
|
|
need gmake since the Makefiles are not compatible with BSD make).
|
|
Note that the cross-powerpc package does not install include files;
|
|
attempting to build U-Boot will fail because <machine/ansi.h> is
|
|
missing. This file has to be installed and patched manually:
|
|
|
|
# cd /usr/pkg/cross/powerpc-netbsd/include
|
|
# mkdir powerpc
|
|
# ln -s powerpc machine
|
|
# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
|
|
# ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
|
|
|
|
Native builds *don't* work due to incompatibilities between native
|
|
and U-Boot include files.
|
|
|
|
Booting assumes that (the first part of) the image booted is a
|
|
stage-2 loader which in turn loads and then invokes the kernel
|
|
proper. Loader sources will eventually appear in the NetBSD source
|
|
tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
|
|
meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
|
|
details.
|
|
|
|
|
|
Implementation Internals:
|
|
=========================
|
|
|
|
The following is not intended to be a complete description of every
|
|
implementation detail. However, it should help to understand the
|
|
inner workings of U-Boot and make it easier to port it to custom
|
|
hardware.
|
|
|
|
|
|
Initial Stack, Global Data:
|
|
---------------------------
|
|
|
|
The implementation of U-Boot is complicated by the fact that U-Boot
|
|
starts running out of ROM (flash memory), usually without access to
|
|
system RAM (because the memory controller is not initialized yet).
|
|
This means that we don't have writable Data or BSS segments, and BSS
|
|
is not initialized as zero. To be able to get a C environment working
|
|
at all, we have to allocate at least a minimal stack. Implementation
|
|
options for this are defined and restricted by the CPU used: Some CPU
|
|
models provide on-chip memory (like the IMMR area on MPC8xx and
|
|
MPC826x processors), on others (parts of) the data cache can be
|
|
locked as (mis-) used as memory, etc.
|
|
|
|
Chris Hallinan posted a good summy of these issues to the
|
|
u-boot-users mailing list:
|
|
|
|
Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
|
|
From: "Chris Hallinan" <clh@net1plus.com>
|
|
Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
|
|
...
|
|
|
|
Correct me if I'm wrong, folks, but the way I understand it
|
|
is this: Using DCACHE as initial RAM for Stack, etc, does not
|
|
require any physical RAM backing up the cache. The cleverness
|
|
is that the cache is being used as a temporary supply of
|
|
necessary storage before the SDRAM controller is setup. It's
|
|
beyond the scope of this list to expain the details, but you
|
|
can see how this works by studying the cache architecture and
|
|
operation in the architecture and processor-specific manuals.
|
|
|
|
OCM is On Chip Memory, which I believe the 405GP has 4K. It
|
|
is another option for the system designer to use as an
|
|
initial stack/ram area prior to SDRAM being available. Either
|
|
option should work for you. Using CS 4 should be fine if your
|
|
board designers haven't used it for something that would
|
|
cause you grief during the initial boot! It is frequently not
|
|
used.
|
|
|
|
CFG_INIT_RAM_ADDR should be somewhere that won't interfere
|
|
with your processor/board/system design. The default value
|
|
you will find in any recent u-boot distribution in
|
|
Walnut405.h should work for you. I'd set it to a value larger
|
|
than your SDRAM module. If you have a 64MB SDRAM module, set
|
|
it above 400_0000. Just make sure your board has no resources
|
|
that are supposed to respond to that address! That code in
|
|
start.S has been around a while and should work as is when
|
|
you get the config right.
|
|
|
|
-Chris Hallinan
|
|
DS4.COM, Inc.
|
|
|
|
It is essential to remember this, since it has some impact on the C
|
|
code for the initialization procedures:
|
|
|
|
* Initialized global data (data segment) is read-only. Do not attempt
|
|
to write it.
|
|
|
|
* Do not use any unitialized global data (or implicitely initialized
|
|
as zero data - BSS segment) at all - this is undefined, initiali-
|
|
zation is performed later (when relocationg to RAM).
|
|
|
|
* Stack space is very limited. Avoid big data buffers or things like
|
|
that.
|
|
|
|
Having only the stack as writable memory limits means we cannot use
|
|
normal global data to share information beween the code. But it
|
|
turned out that the implementation of U-Boot can be greatly
|
|
simplified by making a global data structure (gd_t) available to all
|
|
functions. We could pass a pointer to this data as argument to _all_
|
|
functions, but this would bloat the code. Instead we use a feature of
|
|
the GCC compiler (Global Register Variables) to share the data: we
|
|
place a pointer (gd) to the global data into a register which we
|
|
reserve for this purpose.
|
|
|
|
When chosing a register for such a purpose we are restricted by the
|
|
relevant (E)ABI specifications for the current architecture, and by
|
|
GCC's implementation.
|
|
|
|
For PowerPC, the following registers have specific use:
|
|
R1: stack pointer
|
|
R2: TOC pointer
|
|
R3-R4: parameter passing and return values
|
|
R5-R10: parameter passing
|
|
R13: small data area pointer
|
|
R30: GOT pointer
|
|
R31: frame pointer
|
|
|
|
(U-Boot also uses R14 as internal GOT pointer.)
|
|
|
|
==> U-Boot will use R29 to hold a pointer to the global data
|
|
|
|
Note: on PPC, we could use a static initializer (since the
|
|
address of the global data structure is known at compile time),
|
|
but it turned out that reserving a register results in somewhat
|
|
smaller code - although the code savings are not that big (on
|
|
average for all boards 752 bytes for the whole U-Boot image,
|
|
624 text + 127 data).
|
|
|
|
On ARM, the following registers are used:
|
|
|
|
R0: function argument word/integer result
|
|
R1-R3: function argument word
|
|
R9: GOT pointer
|
|
R10: stack limit (used only if stack checking if enabled)
|
|
R11: argument (frame) pointer
|
|
R12: temporary workspace
|
|
R13: stack pointer
|
|
R14: link register
|
|
R15: program counter
|
|
|
|
==> U-Boot will use R8 to hold a pointer to the global data
|
|
|
|
|
|
|
|
Memory Management:
|
|
------------------
|
|
|
|
U-Boot runs in system state and uses physical addresses, i.e. the
|
|
MMU is not used either for address mapping nor for memory protection.
|
|
|
|
The available memory is mapped to fixed addresses using the memory
|
|
controller. In this process, a contiguous block is formed for each
|
|
memory type (Flash, SDRAM, SRAM), even when it consists of several
|
|
physical memory banks.
|
|
|
|
U-Boot is installed in the first 128 kB of the first Flash bank (on
|
|
TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
|
|
booting and sizing and initializing DRAM, the code relocates itself
|
|
to the upper end of DRAM. Immediately below the U-Boot code some
|
|
memory is reserved for use by malloc() [see CFG_MALLOC_LEN
|
|
configuration setting]. Below that, a structure with global Board
|
|
Info data is placed, followed by the stack (growing downward).
|
|
|
|
Additionally, some exception handler code is copied to the low 8 kB
|
|
of DRAM (0x00000000 ... 0x00001FFF).
|
|
|
|
So a typical memory configuration with 16 MB of DRAM could look like
|
|
this:
|
|
|
|
0x0000 0000 Exception Vector code
|
|
:
|
|
0x0000 1FFF
|
|
0x0000 2000 Free for Application Use
|
|
:
|
|
:
|
|
|
|
:
|
|
:
|
|
0x00FB FF20 Monitor Stack (Growing downward)
|
|
0x00FB FFAC Board Info Data and permanent copy of global data
|
|
0x00FC 0000 Malloc Arena
|
|
:
|
|
0x00FD FFFF
|
|
0x00FE 0000 RAM Copy of Monitor Code
|
|
... eventually: LCD or video framebuffer
|
|
... eventually: pRAM (Protected RAM - unchanged by reset)
|
|
0x00FF FFFF [End of RAM]
|
|
|
|
|
|
System Initialization:
|
|
----------------------
|
|
|
|
In the reset configuration, U-Boot starts at the reset entry point
|
|
(on most PowerPC systens at address 0x00000100). Because of the reset
|
|
configuration for CS0# this is a mirror of the onboard Flash memory.
|
|
To be able to re-map memory U-Boot then jumps to it's link address.
|
|
To be able to implement the initialization code in C, a (small!)
|
|
initial stack is set up in the internal Dual Ported RAM (in case CPUs
|
|
which provide such a feature like MPC8xx or MPC8260), or in a locked
|
|
part of the data cache. After that, U-Boot initializes the CPU core,
|
|
the caches and the SIU.
|
|
|
|
Next, all (potentially) available memory banks are mapped using a
|
|
preliminary mapping. For example, we put them on 512 MB boundaries
|
|
(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
|
|
on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
|
|
programmed for SDRAM access. Using the temporary configuration, a
|
|
simple memory test is run that determines the size of the SDRAM
|
|
banks.
|
|
|
|
When there is more than one SDRAM bank, and the banks are of
|
|
different size, the larger is mapped first. For equal size, the first
|
|
bank (CS2#) is mapped first. The first mapping is always for address
|
|
0x00000000, with any additional banks following immediately to create
|
|
contiguous memory starting from 0.
|
|
|
|
Then, the monitor installs itself at the upper end of the SDRAM area
|
|
and allocates memory for use by malloc() and for the global Board
|
|
Info data; also, the exception vector code is copied to the low RAM
|
|
pages, and the final stack is set up.
|
|
|
|
Only after this relocation will you have a "normal" C environment;
|
|
until that you are restricted in several ways, mostly because you are
|
|
running from ROM, and because the code will have to be relocated to a
|
|
new address in RAM.
|
|
|
|
|
|
U-Boot Porting Guide:
|
|
----------------------
|
|
|
|
[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
|
|
list, October 2002]
|
|
|
|
|
|
int main (int argc, char *argv[])
|
|
{
|
|
sighandler_t no_more_time;
|
|
|
|
signal (SIGALRM, no_more_time);
|
|
alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
|
|
|
|
if (available_money > available_manpower) {
|
|
pay consultant to port U-Boot;
|
|
return 0;
|
|
}
|
|
|
|
Download latest U-Boot source;
|
|
|
|
Subscribe to u-boot-users mailing list;
|
|
|
|
if (clueless) {
|
|
email ("Hi, I am new to U-Boot, how do I get started?");
|
|
}
|
|
|
|
while (learning) {
|
|
Read the README file in the top level directory;
|
|
Read http://www.denx.de/re/DPLG.html
|
|
Read the source, Luke;
|
|
}
|
|
|
|
if (available_money > toLocalCurrency ($2500)) {
|
|
Buy a BDI2000;
|
|
} else {
|
|
Add a lot of aggravation and time;
|
|
}
|
|
|
|
Create your own board support subdirectory;
|
|
|
|
Create your own board config file;
|
|
|
|
while (!running) {
|
|
do {
|
|
Add / modify source code;
|
|
} until (compiles);
|
|
Debug;
|
|
if (clueless)
|
|
email ("Hi, I am having problems...");
|
|
}
|
|
Send patch file to Wolfgang;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void no_more_time (int sig)
|
|
{
|
|
hire_a_guru();
|
|
}
|
|
|
|
|
|
|
|
Coding Standards:
|
|
-----------------
|
|
|
|
All contributions to U-Boot should conform to the Linux kernel
|
|
coding style; see the file "Documentation/CodingStyle" in your Linux
|
|
kernel source directory.
|
|
|
|
Please note that U-Boot is implemented in C (and to some small parts
|
|
in Assembler); no C++ is used, so please do not use C++ style
|
|
comments (//) in your code.
|
|
|
|
Submissions which do not conform to the standards may be returned
|
|
with a request to reformat the changes.
|
|
|
|
|
|
Submitting Patches:
|
|
-------------------
|
|
|
|
Since the number of patches for U-Boot is growing, we need to
|
|
establish some rules. Submissions which do not conform to these rules
|
|
may be rejected, even when they contain important and valuable stuff.
|
|
|
|
|
|
When you send a patch, please include the following information with
|
|
it:
|
|
|
|
* For bug fixes: a description of the bug and how your patch fixes
|
|
this bug. Please try to include a way of demonstrating that the
|
|
patch actually fixes something.
|
|
|
|
* For new features: a description of the feature and your
|
|
implementation.
|
|
|
|
* A CHANGELOG entry as plaintext (separate from the patch)
|
|
|
|
* For major contributions, your entry to the CREDITS file
|
|
|
|
* When you add support for a new board, don't forget to add this
|
|
board to the MAKEALL script, too.
|
|
|
|
* If your patch adds new configuration options, don't forget to
|
|
document these in the README file.
|
|
|
|
* The patch itself. If you are accessing the CVS repository use "cvs
|
|
update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
|
|
version of diff does not support these options, then get the latest
|
|
version of GNU diff.
|
|
|
|
We accept patches as plain text, MIME attachments or as uuencoded
|
|
gzipped text.
|
|
|
|
Notes:
|
|
|
|
* Before sending the patch, run the MAKEALL script on your patched
|
|
source tree and make sure that no errors or warnings are reported
|
|
for any of the boards.
|
|
|
|
* Keep your modifications to the necessary minimum: A patch
|
|
containing several unrelated changes or arbitrary reformats will be
|
|
returned with a request to re-formatting / split it.
|
|
|
|
* If you modify existing code, make sure that your new code does not
|
|
add to the memory footprint of the code ;-) Small is beautiful!
|
|
When adding new features, these should compile conditionally only
|
|
(using #ifdef), and the resulting code with the new feature
|
|
disabled must not need more memory than the old code without your
|
|
modification.
|