README

#
# (C) Copyright 2000 - 2002
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# See file CREDITS for list of people who contributed to this
# project.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
# MA 02111-1307 USA
#

Summary:
========

This directory contains the source code for U-Boot, a boot loader for
Embedded boards based on PowerPC and ARM processors, which can be
installed in a boot ROM and used to initialize and test the hardware
or to download and run application code.

The development of U-Boot is closely related to Linux: some parts of
the source code originate in the Linux source tree, we have some
header files in common, and special provision has been made to
support booting of Linux images.

Some attention has been paid to make this software easily
configurable and extendable. For instance, all monitor commands are
implemented with the same call interface, so that it's very easy to
add new commands. Also, instead of permanently adding rarely used
code (for instance hardware test utilities) to the monitor, you can
load and run it dynamically.


Status:
=======

In general, all boards for which a configuration option exists in the
Makefile have been tested to some extent and can be considered
"working". In fact, many of them are used in production systems.

In case of problems see the CHANGELOG and CREDITS files to find out
who contributed the specific port.


Where to get help:
==================

In case you have questions about, problems with or contributions for
U-Boot you should send a message to the U-Boot mailing list at
<u-boot-users@lists.sourceforge.net>. There is also an archive of
previous traffic on the mailing list - please search the archive
before asking FAQ's. Please see
http://lists.sourceforge.net/lists/listinfo/u-boot-users/


Where we come from:
===================

- start from 8xxrom sources
- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
- clean up code
- make it easier to add custom boards
- make it possible to add other [PowerPC] CPUs
- extend functions, especially:
  * Provide extended interface to Linux boot loader
  * S-Record download
  * network boot
  * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
- create ARMBoot project (http://sourceforge.net/projects/armboot)
- add other CPU families (starting with ARM)
- create U-Boot project (http://sourceforge.net/projects/u-boot)


Names and Spelling:
===================

The "official" name of this project is "Das U-Boot". The spelling
"U-Boot" shall be used in all written text (documentation, comments
in source files etc.). Example:

	This is the README file for the U-Boot project.

File names etc. shall be based on the string "u-boot". Examples:

	include/asm-ppc/u-boot.h

	#include <asm/u-boot.h>

Variable names, preprocessor constants etc. shall be either based on
the string "u_boot" or on "U_BOOT". Example:

	U_BOOT_VERSION		u_boot_logo
	IH_OS_U_BOOT		u_boot_hush_start


Versioning:
===========

U-Boot uses a 3 level version number containing a version, a
sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
sub-version "34", and patchlevel "4".

The patchlevel is used to indicate certain stages of development
between released versions, i. e. officially released versions of
U-Boot will always have a patchlevel of "0".


Directory Hierarchy:
====================

- board		Board dependend files
- common	Misc architecture independend functions
- cpu		CPU specific files
- disk		Code for disk drive partition handling
- doc		Documentation (don't expect too much)
- drivers	Common used device drivers
- dtt		Digital Thermometer and Thermostat drivers
- examples	Example code for standalone applications, etc.
- include	Header Files
- disk		Harddisk interface code
- net		Networking code
- ppc		Files generic to PowerPC architecture
- post		Power On Self Test
- post/arch		Symlink to architecture specific Power On Self Test
- post/arch-ppc		PowerPC architecture specific Power On Self Test
- post/cpu/mpc8260	MPC8260 CPU specific Power On Self Test
- post/cpu/mpc8xx	MPC8xx CPU specific Power On Self Test
- rtc		Real Time Clock drivers
- tools		Tools to build S-Record or U-Boot images, etc.

- cpu/74xx_7xx	Files specific to Motorola MPC74xx and 7xx CPUs
- cpu/mpc8xx	Files specific to Motorola MPC8xx  CPUs
- cpu/mpc824x	Files specific to Motorola MPC824x CPUs
- cpu/mpc8260	Files specific to Motorola MPC8260 CPU
- cpu/ppc4xx	Files specific to IBM	   4xx	   CPUs

- board/RPXClassic
		Files specific to RPXClassic boards
- board/RPXlite	Files specific to RPXlite    boards
- board/c2mon	Files specific to c2mon	     boards
- board/cogent	Files specific to Cogent     boards
		(need further configuration)
		Files specific to CPCIISER4  boards
- board/cpu86	Files specific to CPU86      boards
- board/cray/	Files specific to boards manufactured by Cray
- board/cray/L1		Files specific to L1         boards
- board/cu824	Files specific to CU824	     boards
- board/ebony   Files specific to IBM Ebony board
- board/eric	Files specific to ERIC	     boards
- board/esd/	Files specific to boards manufactured by ESD
- board/esd/adciop	Files specific to ADCIOP     boards
- board/esd/ar405	Files specific to AR405	     boards
- board/esd/canbt	Files specific to CANBT	     boards
- board/esd/cpci405	Files specific to CPCI405    boards
- board/esd/cpciiser4	Files specific to CPCIISER4  boards
- board/esd/common	Common files for ESD boards
- board/esd/dasa_sim	Files specific to DASA_SIM   boards
- board/esd/du405	Files specific to DU405      boards
- board/esd/ocrtc	Files specific to OCRTC      boards
- board/esd/pci405	Files specific to PCI405     boards
- board/esteem192e
		Files specific to ESTEEM192E boards
- board/etx094	Files specific to ETX_094    boards
- board/evb64260
		Files specific to EVB64260   boards
- board/fads	Files specific to FADS	     boards
- board/flagadm Files specific to FLAGADM    boards
- board/gen860t Files specific to GEN860T    boards
- board/genietv Files specific to GENIETV    boards
- board/gth	Files specific to GTH	     boards
- board/hermes	Files specific to HERMES     boards
- board/hymod	Files specific to HYMOD	     boards
- board/icu862	Files specific to ICU862     boards
- board/ip860	Files specific to IP860	     boards
- board/iphase4539
		Files specific to Interphase4539 boards
- board/ivm	Files specific to IVMS8/IVML24 boards
- board/lantec	Files specific to LANTEC     boards
- board/lwmon	Files specific to LWMON	     boards
- board/mbx8xx	Files specific to MBX	     boards
- board/mpc8260ads
		Files specific to MMPC8260ADS boards
- board/mpl/	Files specific to boards manufactured by MPL
- board/mpl/common	Common files for MPL boards
- board/mpl/pip405	Files specific to PIP405     boards
- board/mpl/mip405	Files specific to MIP405     boards
- board/musenki	Files specific to MUSEKNI    boards
- board/mvs1	Files specific to MVS1       boards
- board/nx823   Files specific to NX823      boards