[coreboot-gerrit] Change in coreboot[master]: Add support on ADL to provide a list of D-states required to enter LPM

[Tarun Tuli (Code Review)]

Attention is currently required from: Lance Zhao, Tarun Tuli, Subrata Banik, Tim Wawrzynczak.
Hello Lance Zhao, build bot (Jenkins), Subrata Banik, Tim Wawrzynczak,

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

https://review.coreboot.org/c/coreboot/+/63969

to look at the new patch set (#6).

Change subject: Add support on ADL to provide a list of D-states required to enter LPM
......................................................................

Add support on ADL to provide a list of D-states required to enter LPM

This change implements sub-function 1 (Get Device Constraints)
of the Low Power S0 Idle Device-Specific Method (_DSM).
That is, a way in which to describe various devices required D-states
to enter LPM (S0ix).  This information can be used to help in diagnostics
and understanding of S0ix entry failure.  For example, the Kernel could
use this to print messages immediately before s2idle of those devices
that are not yet in the required D-state for LPM.

This change applies to ADL in particular, but similar porting work
can be carried over to other SoC's next to provide similar functionality.
Should an existing SoC not have this new implementation, it will
default back the old behavior of returning a single hardcoded device to
ensure Windows does not run into issues.

TEST=Built and tested on brya by verifying SSDT contents

Change-Id: Ibe46a0583c522a8adf0a015cd3a698f694482437
Signed-off-by: Tarun Tuli 
---
M src/acpi/acpi.c
M src/include/acpi/acpi.h
M src/soc/intel/alderlake/acpi.c
M src/soc/intel/alderlake/chip.c
M src/soc/intel/common/block/acpi/pep.c
M src/soc/intel/common/block/uart/uart.c
6 files changed, 418 insertions(+), 26 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/69/63969/6