mb/google/{zork,guybrush,skyrim},soc/amd/espi: Fix vw_irq_polarity

The default state for the IRQ lines when the eSPI controller comes out
of reset is high. This is because the IRQ lines are shared with the
other IRQ sources using AND gates. This means that in order to not cause
any spurious interrupts or miss any interrupts, the IO-APIC must use a
low polarity trigger.

On zork/guybrush/skyrim the eSPI IRQs are currently working as follows:
* On power on/resume the eSPI controller drives IRQ 1 high.
* eSPI controller gets configured to not invert IRQ 1.
* OS configures IO-APIC IRQ 1 as Edge/High.
* EC writes to HIKDO (Keyboard Data Out) which causes the EC to set IRQ1
  high.
* eSPI controller receives IRQ 1 high, doesn't invert it, and leaves IRQ
  1 as high. This results in missing the first interrupt.
* When the x86 reads from HIKDO, the EC deasserts IRQ1. This causes the
  eSPI controller to set IRQ1 to low. We are now primed to catch the
  next edge high interrupt. This is generally not a problem since the
  linux driver will probe the 8042 with interrupts off.

On S3/S0i3 resume since the eSPI controller comes out of reset driving
the IRQ lines high, we trigger a spurious IRQ since the IO-APIC is
configured to trigger on edge high. This results in the 8042 controller
getting incorrectly marked as a wake trigger.

By configuring the IO-APIC to use low polarity interrupts, we no longer
lose the first interrupt. This also means we can use a level interrupt
to match what the EC actually asserts.

We use the `Interrupt` keyword instead of the `IRQ` keyword in the ACPI
because the linux kernel will ignore the level/polarity parameters
for the `IRQ` keyword and default to `edge/high. `Interrupt` doesn't
have this problem.

The PIC is not currently configured anywhere and it defaults to an
edge/high trigger. We could add some code to configure the PICs trigger
register, but I don't think we need the functionality right now.

For zork and guybrush, this change is a no-op. eSPI is configured in
verstage which is located in RO, and we have already locked RO for
these devices. We will need to figure out how to properly set the
`vw_irq_polarity` for these devices.

BUG=b:218874489, b:160595155, b:184752352, b:157984427, b:238818104
TEST=On zork, guybrush and skyrim
$ suspend_stress_test --post_resume_command 'cat /sys/devices/platform/i8042/serio0/wakeup/wakeup35/active_count'
Verify keyboard works as expected and no interrupt storms are observed.

On morphius I verified keyboard and mouse work on windows as well.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I4608a7684e34ebb389e0e55ceba7e7441939afe7
Reviewed-on: https://review.coreboot.org/c/coreboot/+/54924
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
5 files changed
tree: 6abc64bff40acaeb815dcf08c6253832728cda9e
  1. 3rdparty/
  2. configs/
  3. Documentation/
  4. LICENSES/
  5. payloads/
  6. spd/
  7. src/
  8. tests/
  9. util/
  10. .checkpatch.conf
  11. .clang-format
  12. .editorconfig
  13. .gitignore
  14. .gitmodules
  15. .gitreview
  16. .mailmap
  17. AUTHORS
  18. COPYING
  19. gnat.adc
  20. MAINTAINERS
  21. Makefile
  22. Makefile.inc
  23. README.md
  24. toolchain.inc
README.md

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:

  • gdb (for better debugging facilities on some targets)
  • ncurses (for make menuconfig and make 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:

https://www.coreboot.org

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.