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Sol Boucher 67a0a864be cbfstool: New image format w/ required FMAP and w/o CBFS master header
These new-style firmware images use the FMAP of the root of knowledge
about their layout, which allows them to have sections containing raw
data whose offset and size can easily be determined at runtime or when
modifying or flashing the image. Furthermore, they can even have
multiple CBFSes, each of which occupies a different FMAP region. It is
assumed that the first entry of each CBFS, including the primary one,
will be located right at the start of its region. This means that the
bootblock needs to be moved into its own FMAP region, but makes the
CBFS master header obsolete because, with the exception of the version
and alignment, all its fields are redundant once its CBFS has an entry
in the FMAP. The version code will be addressed in a future commit
before the new format comes into use, while the alignment will just be
defined to 64 bytes in both cbfstool and coreboot itself, since
there's almost no reason to ever change it in practice. The version
code field and all necessary coreboot changes will come separately.

BUG=chromium:470407
TEST=Build panther and nyan_big coreboot.rom and image.bin images with
and without this patch, diff their hexdumps, and note that no
locations differ except for those that do between subsequent builds of
the same codebase. Try working with new-style images: use fmaptool to
produce an FMAP section from an fmd file having raw sections and
multiple CBFSes, pass the resulting file to cbfstool create -M -F,
then try printing its layout and CBFSes' contents, add and remove CBFS
files, and read and write raw sections.
BRANCH=None

Change-Id: I7dd2578d2143d0cedd652fdba5b22221fcc2184a
Signed-off-by: Sol Boucher <solb@chromium.org>
Original-Commit-Id: 8a670322297f83135b929a5b20ff2bd0e7d2abd3
Original-Change-Id: Ib86fb50edc66632f4e6f717909bbe4efb6c874e5
Original-Signed-off-by: Sol Boucher <solb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/265863
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10135
Tested-by: build bot (Jenkins)
2015-05-13 22:19:59 +02:00
3rdparty 3rdparty/vboot: Add vboot 2015-05-05 22:49:34 +02:00
Documentation Rename documentation -> Documentation 2015-05-06 19:09:47 +02:00
payloads libpayload: x86: correct types used for IO 2015-05-13 15:39:54 +02:00
src secmon: allow for serial console 2015-05-13 20:54:00 +02:00
util cbfstool: New image format w/ required FMAP and w/o CBFS master header 2015-05-13 22:19:59 +02:00
.gitignore fmaptool: Introduce the fmd ("flashmap descriptor") language and compiler 2015-05-08 19:55:42 +02:00
.gitmodules 3rdparty/vboot: Add vboot 2015-05-05 22:49:34 +02:00
.gitreview
COPYING
MAINTAINERS MAINTAINERS: Add lint scripts 2015-05-07 19:41:22 +02:00
Makefile make: support absolute and relative obj= specifications 2015-05-08 19:47:11 +02:00
Makefile.inc fmaptool: Introduce the fmd ("flashmap descriptor") language and compiler 2015-05-08 19:55:42 +02:00
README Update README with newer version of the text from the web page 2011-06-15 10:16:33 +02:00
toolchain.inc vboot: split class in library and stage 2015-04-30 15:39:53 +02:00

README

-------------------------------------------------------------------------------
coreboot README
-------------------------------------------------------------------------------

coreboot is a Free Software project aimed at replacing the proprietary BIOS
(firmware) found in most computers.  coreboot performs a little bit of
hardware initialization and then executes additional boot logic, called a
payload.

With the separation of hardware initialization and later boot logic,
coreboot can scale from specialized applications that run directly
firmware, run operating systems in flash, load custom
bootloaders, or implement firmware standards, like PC BIOS services or
UEFI. This allows for systems to only include the features necessary
in the target application, reducing the amount of code and flash space
required.

coreboot was formerly known as LinuxBIOS.


Payloads
--------

After the basic initialization of the hardware has been performed, any
desired "payload" can be started by coreboot.

See http://www.coreboot.org/Payloads for a list of supported payloads.


Supported Hardware
------------------

coreboot supports a wide range of chipsets, devices, and mainboards.

For details please consult:

 * http://www.coreboot.org/Supported_Motherboards
 * http://www.coreboot.org/Supported_Chipsets_and_Devices


Build Requirements
------------------

 * gcc / g++
 * make

Optional:

 * doxygen (for generating/viewing documentation)
 * iasl (for targets with ACPI support)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig')
 * flex and bison (for regenerating parsers)


Building coreboot
-----------------

Please consult http://www.coreboot.org/Build_HOWTO for details.


Testing coreboot Without Modifying Your Hardware
------------------------------------------------

If you want to test coreboot without any risks before you really decide
to use it on your hardware, you can use the QEMU system emulator to run
coreboot virtually in QEMU.

Please see http://www.coreboot.org/QEMU for details.


Website and Mailing List
------------------------

Further details on the project, a FAQ, many HOWTOs, news, development
guidelines and more can be found on the coreboot website:

  http://www.coreboot.org

You can contact us directly on the coreboot mailing list:

  http://www.coreboot.org/Mailinglist


Copyright and License
---------------------

The copyright on coreboot is owned by quite a large number of individual
developers and companies. Please check the individual source files for details.

coreboot is licensed under the terms of the GNU General Public License (GPL).
Some files are licensed under the "GPL (version 2, or any later version)",
and some files are licensed under the "GPL, version 2". For some parts, which
were derived from other projects, other (GPL-compatible) licenses may apply.
Please check the individual source files for details.

This makes the resulting coreboot images licensed under the GPL, version 2.