[PATCH v16 0/3] Avoid PCIe D3 for AMD PCIe root ports

From: Mario Limonciello
Date: Tue Aug 29 2023 - 15:29:29 EST


D3 on PCIe root ports isn't used on Windows systems in Modern Standby.
This series adjusts the amd-pmc driver to choose the same strategy
for Rembrandt and Phoenix platforms in Linux with s2idle.

LPS0 constraints are the basis for it; which if they are added for
Windows would also apply for Linux as well.

This version doesn't incorporate a callback, as it's pending feedback
from Bjorn if that approach is amenable.

NOTE:
This series relies upon changes that are both in linux-pm.git and
platform-x86.git. So it won't be able to apply to either maintainer's
tree until later.

Mario Limonciello (3):
ACPI: x86: s2idle: Export symbol for fetching constraints for module
use
platform/x86/amd: pmc: Adjust workarounds to be part of a switch/case
platform/x86/amd: pmc: Don't let PCIe root ports go into D3

drivers/acpi/x86/s2idle.c | 1 +
drivers/platform/x86/amd/pmc/pmc.c | 56 ++++++++++++++++++++++++++----
2 files changed, 50 insertions(+), 7 deletions(-)

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2.34.1