[coreboot-gerrit] Change in coreboot[master]: soc/intel/{common,skl}: set ACPI_FADT_PLATFORM_CLOCK based on Kconfig

[Michael Niewöhner (Code Review)]

Attention is currently required from:  Felix Singer, Furquan Shaikh, Mariusz Szafrański, Paul Menzel, Subrata Banik, Angel Pons, Patrick Rudolph, Lance Zhao, Nico Huber, Tim Wawrzynczak, Suresh Bellampalli, Vanessa Eusebio, Michal Motyl.
Hello  Felix Singer, build bot (Jenkins), Furquan Shaikh, Mariusz Szafrański, Paul Menzel, Angel Pons, Subrata Banik, Patrick Rudolph, Lance Zhao, Nico Huber, Tim Wawrzynczak, Suresh Bellampalli, Vanessa Eusebio, Michal Motyl,

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

https://review.coreboot.org/c/coreboot/+/57934

to look at the new patch set (#23).

Change subject: soc/intel/{common,skl}: set ACPI_FADT_PLATFORM_CLOCK based on Kconfig
......................................................................

soc/intel/{common,skl}: set ACPI_FADT_PLATFORM_CLOCK based on Kconfig

The FADT contains a flag `ACPI_FADT_PLATFORM_CLOCK` telling the OSPM if a
specification-compliant PM Timer is present. Currently, this flag is set
regardless of the timer being enabled or disabled.

To be specification-compliant, only set that flag, when the hardware PM
Timer is enabled. This changes behaviour of:

- all mainboards defaulting to USE_PM_ACPI_TIMER=n
 - Apollo Lake and Gemini Lake, which do not have a hardware PM timer

Note: On platforms supporting uCode PM ACPI Timer emulation, this is
      required, too, because emulation does not support `TMR_STS`. Any
      OS or software checking this flag and thus relying on the overflow
      flag would not work (properly).

Change-Id: Id2e5d69b5515c21e6ce922dab2cb88b494c65ebe
Signed-off-by: Michael Niewöhner 
---
M src/soc/intel/common/block/acpi/acpi.c
M src/soc/intel/skylake/fadt.c
2 files changed, 8 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/34/57934/23