7f844ab8b7
For Volteer (and future Tiger Lake boards) we can enable mode S0i3.4 only if we know that the Cr50 is generating 100us interrupt pulses. We have to do so, because the SoC is not guaranteed to detect pulses shorter than 100us in S0i3.4 substate. A new Kconfig setting CR50_USE_LONG_INTERRUPT_PULSES controls new code running in verstage, which will program a new Cr50 register, provided that Cr50 firmware is new enough to support the register. This CL adds code to detect the case when Cr50 is unable to generate longer pulses, and in that case explicitly disable the S0i3.4 substate as well as setting gpio_pm_override to all zeroes. This will increase power usage slightly, but guarantee that the GPIO block in the SoC does not switch to a slower sampling clock. In practice, this case will only be encountered in the factory, before the Cr50 chip is updated to a new RW image. (Prior to this change, the gpio_pm_override was hardcoded to zero for Volteer, but the S0i3.4 substate was not disabled. According to my conversations with Intel engineers, that was not enough to guarantee detection pulses shorter than 100us. But it is entirely possible that we have just been "lucky" that the SoC has not gone into low power mode during the boot process, where most of the cr50 communication happens.) TEST=util/abuild/abuild -t GOOGLE_VOLTEER -c max -x BUG=b:154333137 Change-Id: Idef1fffd410a345678da4b3c8aea46ac74a01470 Signed-off-by: Jes Bodi Klinke <jbk@chromium.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/44359 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org> |
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|---|---|---|
| 3rdparty | ||
| configs | ||
| Documentation | ||
| LICENSES | ||
| payloads | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| AUTHORS | ||
| COPYING | ||
| gnat.adc | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README.md | ||
| 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 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_TOOLCHAINKconfig 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 menuconfigandmake 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.