For additional power savings during RTD3, the PMC can power-gate the
ModPHY lanes that are used by the PCH PCIe root ports. Therefore,
using the previous PCIe RP-type detection functions, implement ModPHY
PG support for the PCH PCIe RPs.
This involves:
1) Adding a mutex so only one power resource accesses the PMC registers
at a time
2) OperationRegions to access the PMC's PG registers
3) Adding ModPHY PG enable sequence to _OFF
4) Adding ModPHY PG disable sequence to _ON
BUG=b:197983574
TEST=50 S0ix suspend/resume cycles on brya0
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I19cb05a74acfa3ded7867b1cac32c161a83b4f7d
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59855
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-by: Cliff Huang <cliff.huang@intel.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
32f883e532