[L] Change in coreboot[master]: soc/intel/common/block/oc_wdt: Add OC watchdog common block

[Michał Żygowski (Code Review)]

Attention is currently required from: Michał Żygowski, Michał Kopeć.

Hello build bot (Jenkins), Michał Kopeć,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/68944

to look at the new patch set (#3).

Change subject: soc/intel/common/block/oc_wdt: Add OC watchdog common block
......................................................................

soc/intel/common/block/oc_wdt: Add OC watchdog common block

Add new block for handling overcloking watchdog. The watchdog is
present since Skylake or maybe even earlier so it is safe to use with
most of the micrarchitectures utilizing intelblocks.

Some FSPs are also utilizing OC watchdog so care must be taken when
initializing it. Example integration provided in subsequent patch.
The goal is to provide coreboot with additional reliability settings.

The patch adds the common block for initializing and feeding the
watchdog. Timeout is configurable via Kconfig and cannot be set to
less than 60 seconds to avoid reset loops when full memory training
is needed.

The patch also adds support for feeding watchdog in driveless mode,
i.e. it utilizies periodic SMI to reload the timeout value and restart
the watchdog timer. This is optional and selectable by Kconfig option
as well. If the option is not enabled, payload and/or software must
ensure to keep feeding the watchdog, otherwise the platform will
reset.

Common SMM drivers have also been extended with new APM command
to reset/reboot platform and additionally allow known reset for reboot
and shutdown in SMI handlers. Platforms should use the new APM command
in FADT as reboot value via SMI if watchdog is enabled. This however
assumes that no software writes directly to 0xcf9 port to reset
platform, otherwise the reset will be treated as unexpected one.
Example is added in subsequent patch for Alder Lake.

TEST=Enable watchdog on MSI PRO Z690-A and see the platform resets
after some time. Enable the watchdog in driverless mode and see the
platform no longer resets and periodic SMI keeps feeding the watchdog.

Signed-off-by: Michał Żygowski 
Change-Id: Ib494aa0c7581351abca8b496fc5895b2c7cbc5bc
---
M src/arch/x86/Makefile.inc
M src/include/cpu/x86/smm.h
A src/soc/intel/common/block/include/intelblocks/oc_wdt.h
A src/soc/intel/common/block/oc_wdt/Kconfig
A src/soc/intel/common/block/oc_wdt/Makefile.inc
A src/soc/intel/common/block/oc_wdt/oc_wdt.c
M src/soc/intel/common/block/smm/smihandler.c
M src/soc/intel/common/block/smm/smm.c
8 files changed, 363 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/44/68944/3