Tim Wawrzynczak has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/67278 )
Change subject: mb/google/brya/acpi: Move dGPU power checks earlier ......................................................................
mb/google/brya/acpi: Move dGPU power checks earlier
Linux always "turns on" a PowerResource when it boots, regardless of _STA, so the _ON routine should be idempotent. In this case, it all is, except for the LTR restore, which would restore a value of 0 when _ON is run the first time, which means that LTR is disabled on the root port from then on, as the save/restore routines will keep saving/restoring that 0. THis patch fixes the problem by moving the power checks from PGON/PGOF to GCOO/GCOI.
BUG=b:244409563 TEST=boot agah and verify that LTR is still enabled on the root port
Signed-off-by: Tim Wawrzynczak twawrzynczak@chromium.org Change-Id: I4ed78323608eede5b8310598f1f1115497ab2b5b --- M src/mainboard/google/brya/acpi/power.asl 1 file changed, 33 insertions(+), 13 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/78/67278/1
diff --git a/src/mainboard/google/brya/acpi/power.asl b/src/mainboard/google/brya/acpi/power.asl index 8940e60..f79a44a 100644 --- a/src/mainboard/google/brya/acpi/power.asl +++ b/src/mainboard/google/brya/acpi/power.asl @@ -182,12 +182,6 @@ /* GCOFF exit sequence */ Method (PGON, 0, Serialized) { - If (GPPS == GPU_POWER_STATE_ON) - { - Printf ("PGON: GPU already on") - Return - } - Local0 = Timer - GCOT If (Local0 < MIN_OFF_TIME_TIMERS) { @@ -234,12 +228,6 @@ /* GCOFF entry sequence */ Method (PGOF, 0, Serialized) { - If (GPPS == GPU_POWER_STATE_OFF) - { - Printf ("GPU already off") - Return - } - /* Assert PERST# */ CTXS (GPIO_GPU_PERST_L)
@@ -278,6 +266,12 @@ /* GCOFF Out, i.e. full power-on sequence */ Method (GCOO, 0, Serialized) { + If (GPPS == GPU_POWER_STATE_ON) + { + Printf ("PGON: GPU already on") + Return + } + SRCC (SRCCLK_ENABLE) PGON () _SB.PCI0.PEG0.LD23 () @@ -310,9 +304,14 @@ /* GCOFF In, i.e. full power-off sequence */ Method (GCOI, 0, Serialized) { + If (GPPS == GPU_POWER_STATE_OFF) + { + Printf ("GPU already off") + Return + } + /* Save the PEG port's LTR setting */ SLTR = LREN - _SB.PCI0.PEG0.DL23 () PGOF () SRCC (SRCCLK_DISABLE)