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67a0a864be
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) |
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| 3rdparty | ||
| Documentation | ||
| payloads | ||
| src | ||
| util | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README | ||
| toolchain.inc | ||
------------------------------------------------------------------------------- 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.