Windows does not comply with the Low Power Idle S0 specification and crashes with an `INTERNAL_POWER_ERROR` bluescreen when function 1, does not return at least one device constraint, even when function 1 is announced as being not available by the enum function. Returning an empty package does not work. At least the following Windows versions were verified to be affected: - Windows 8.1 x64, release 6.3.9600 - Windoes 10 x64, version 1809, build 17763.379 - Windows 10 x64, version 1903, build 18362.53 - Windows 10 x64, version 2004, build 19041.508 - Windows 10 x64, version 20H2 / 2009, build 19042.450 To make Windows work on S0ix-enabled boards, return a dummy constraint package with a disabled dummy device. Since the device constraints are only used for debugging low power states in Linux and probably also in Windows, there shouldn't be any negative effect to S0ix. Real device constraint entries could be added at a later point, if needed. Note: to fully prevent the BSOD mentioned above the LPIT table is required on Windows, too. The patch for this is WIP, see CB:32350. If you want to test this, you need to applie the whole ACPI patch series including the hacky LPIT test implementation from CB:47242: https://review.coreboot.org/q/topic:%22low_power_idle_fix%22 Test: no bluescreen anymore on Clevo L140CU on all Windows versions listed above and S0ix gets detected in `powercfg -a`. Change-Id: Icd08cbcb1dfcb8cbb23f4f4c902bf8c367c8e3ac Signed-off-by: Michael Niewöhner <foss@mniewoehner.de> Reviewed-on: https://review.coreboot.org/c/coreboot/+/47138 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
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 https://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:
Build Requirements
- make
- gcc / g++
Because Linux distribution compilers tend to use lots of patches. coreboot
does lots of "unusual" things in its build system, some of which break due
to those patches, sometimes by gcc aborting, sometimes - and that's worse -
by generating broken object code.
Two options: use our toolchain (eg. make crosstools-i386) or enable the
ANY_TOOLCHAIN
Kconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- doxygen (for generating/viewing documentation)
- gdb (for better debugging facilities on some targets)
- ncurses (for
make menuconfig
andmake nconfig
) - flex and bison (for regenerating parsers)
Building coreboot
Please consult https://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 https://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:
You can contact us directly on the coreboot mailing list:
https://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.