Felix Held bfc92cb944 device: drop unnecessary CHECK_REV_IN_OPROM_NAME option
The CHECK_REV_IN_OPROM_NAME Kconfig option was introduced to solve the
problem of the PCI VID/DID combination of the Picasso iGPU not being
sufficient information to know which VGA BIOS file to run, so a new
function that additionally checks the PCI revision of that device was
introduced. Later it turned out that there might be a case where even
that isn't sufficient, so the soc_is_raven2() function is used in the
remap function to always use the correct VBIOS file.

Picasso is the only SoC that selected the CHECK_REV_IN_OPROM_NAME
Kconfig option, so all other SoCs are unaffected by this change.

Now that we use the VBIOS images with only the PCI VID and DID in the
CBFS file name for Picasso, SeaBIOS will find the VBIOS with the same ID
as the iGPU in CBFS and we don't need the workaround to add a third
VBIOS image via VGA_BIOS_DGPU_* that has the name that SeaBIOS expects.
This will result in SeaBIOS now running the VBIOS that has the same PCI
VID/DID as the hardware which will be the wrong one in the RV2 silicon
showing the PCO silicon PCI VID/DID, but that was also the case with the
VGA_BIOS_DGPU_* workaround where the board's Kconfig just selected one
of the two possible images during build time and hoped that it was the
correct one for that actual hardware. The only board where this patch
might cause a regression compared to the old behavior is the AMD Cereme
reference board with Pollock APU, but I'm not even sure if any coreboot
developer still has one of those boards, so I'm willing to accept that.

To properly solve the problem with SeaBIOS using the correct VBIOS file
in all cases, we'd need to generate that info during coreboot runtime
and somehow pass it to SeaBIOS, but that's out of scope for this patch.

TEST=On Mandolin with PCO silicon, the display output in both SeaBIOS
and Ubuntu still works. Booting Windows 10 via the pre-built EDK2
payload that I'm using also resulted in the display output working.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: Ia6de533c536044698d85404427719b8f534870fa
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82598
Reviewed-by: Matt DeVillier <matt.devillier@amd.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2024-05-23 21:54:26 +00:00
2024-02-18 01:56:38 +00:00
2022-03-08 18:53:47 +00:00
2006-08-12 22:03:36 +00:00
2024-01-04 14:22:51 +00:00

coreboot README

coreboot is a Free Software project aimed at replacing the proprietary firmware (BIOS/UEFI) found in most computers. coreboot performs the required hardware initialization to configure the system, then passes control to a different executable, referred to in coreboot as the payload. Most often, the primary function of the payload is to boot the operating system (OS).

With the separation of hardware initialization and later boot logic, coreboot is perfect for a wide variety of situations. It can be used for specialized applications that run directly in the firmware, running operating systems from flash, loading custom bootloaders, or implementing firmware standards, like PC BIOS services or UEFI. This flexibility allows coreboot systems to include only the features necessary in the target application, reducing the amount of code and flash space required.

Source code

All source code for coreboot is stored in git. It is downloaded with the command:

git clone https://review.coreboot.org/coreboot.git.

Code reviews are done in the project's Gerrit instance.

The code may be browsed via coreboot's Gitiles instance.

The coreboot project also maintains a mirror of the project on github. This is read-only, as coreboot does not accept github pull requests, but allows browsing and downloading the coreboot source.

Payloads

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

See https://doc.coreboot.org/payloads.html for a list of some of coreboot's supported payloads.

Supported Hardware

The coreboot project supports a wide range of architectures, chipsets, devices, and mainboards. While not all of these are documented, you can find some information in the Architecture-specific documentation or the SOC-specific documentation.

For details about the specific mainboard devices that coreboot supports, please consult the Mainboard-specific documentation or the Board Status pages.

Releases

Releases are currently done by coreboot every quarter. The release archives contain the entire coreboot codebase from the time of the release, along with any external submodules. The submodules containing binaries are separated from the general release archives. All of the packages required to build the coreboot toolchains are also kept at coreboot.org in case the websites change, or those specific packages become unavailable in the future.

All releases are available on the coreboot download page.

Please note that the coreboot releases are best considered as snapshots of the codebase, and do not currently guarantee any sort of extra stability.

Build Requirements and building coreboot

The coreboot build, associated utilities and payloads require many additional tools and packages to build. The actual coreboot binary is typically built using a coreboot-controlled toolchain to provide reproducibility across various platforms. It is also possible, though not recommended, to make it directly with your system toolchain. Operating systems and distributions come with an unknown variety of system tools and utilities installed. Because of this, it isn't reasonable to list all the required packages to do a build, but the documentation lists the requirements for a few different Linux distributions.

To see the list of tools and libraries, along with a list of instructions to get started building coreboot, go to the Starting from scratch tutorial page.

That same page goes through how to use QEMU to boot the build and see the output.

Website and Mailing List

Further details on the project, as well as links to documentation and more can be found on the coreboot website:

https://www.coreboot.org

You can contact us directly on the coreboot mailing list:

https://doc.coreboot.org/community/forums.html

Copyrights and Licenses

Uncopyrightable files

There are many files in the coreboot tree that we feel are not copyrightable due to a lack of creative content.

"In order to qualify for copyright protection in the United States, a work must satisfy the originality requirement, which has two parts. The work must have “at least a modicum” of creativity, and it must be the independent creation of its author."

https://guides.lib.umich.edu/copyrightbasics/copyrightability

Similar terms apply to other locations.

These uncopyrightable files include:

  • Empty files or files with only a comment explaining their existence. These may be required to exist as part of the build process but are not needed for the particular project.
  • Configuration files either in binary or text form. Examples would be files such as .vbt files describing graphics configuration, .apcb files containing configuration parameters for AMD firmware binaries, and spd files as binary .spd or text *spd*.hex representing memory chip configuration.
  • Machine-generated files containing version numbers, dates, hash values or other "non-creative" content.

As non-creative content, these files are in the public domain by default. As such, the coreboot project excludes them from the project's general license even though they may be included in a final binary.

If there are questions or concerns about this policy, please get in touch with the coreboot project via the mailing list.

Copyrights

The copyright on coreboot is owned by quite a large number of individual developers and companies. A list of companies and individuals with known copyright claims is present at the top level of the coreboot source tree in the 'AUTHORS' file. Please check the git history of each of the source files for details.

Licenses

Because of the way coreboot began, using a significant amount of source code from the Linux kernel, it's licensed the same way as the Linux Kernel, with GNU General Public License (GPL) Version 2. Individual files are licensed under various licenses, though all are compatible with GPLv2. The resulting coreboot image is licensed under the GPL, version 2. All source files should have an SPDX license identifier at the top for clarification.

Files under coreboot/Documentation/ are licensed under CC-BY 4.0 terms. As an exception, files under Documentation/ with a history older than 2017-05-24 might be under different licenses.

Files in the coreboot/src/commonlib/bsd directory are all licensed with the BSD-3-clause license. Many are also dual-licensed GPL-2.0-only or GPL-2.0-or-later. These files are intended to be shared with libpayload or other BSD licensed projects.

The libpayload project contained in coreboot/payloads/libpayload may be licensed as BSD or GPL, depending on the code pulled in during the build process. All GPL source code should be excluded unless the Kconfig option to include it is set.

The Software Freedom Conservancy

Since 2017, coreboot has been a member of The Software Freedom Conservancy, a nonprofit organization devoted to ethical technology and driving initiatives to make technology more inclusive. The conservancy acts as coreboot's fiscal sponsor and legal advisor.

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