mb/google/brya/acpi: Keep track of dGPU power state
To avoid extraneous calls from the kernel to _ON or _OFF, keep track
of the power state of the GPU in an integer and exit _ON and _OFF
routines early when attempting to enter the current state.
BUG=b:236676400
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: Ie874fcdc7022c4fde6f557d1ee06e8392ae3d850
Reviewed-on: https://review.coreboot.org/c/coreboot/+/65482
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Robert Zieba <robertzieba@google.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/mainboard/google/brya/acpi/power.asl b/src/mainboard/google/brya/acpi/power.asl
index 8232a32..daaba74 100644
--- a/src/mainboard/google/brya/acpi/power.asl
+++ b/src/mainboard/google/brya/acpi/power.asl
@@ -23,7 +23,7 @@
Name (OPCS, OPTIMUS_POWER_CONTROL_DISABLE)
/* PCI configuration space Owner */
-Name (PCIO, PCI_OWNER_SBIOS)
+Name (PCIO, PCI_OWNER_DRIVER)
/* Saved PCI configuration space memory (VGA Buffer) */
Name (VGAB, Buffer (0xfb) { 0x00 })
@@ -34,6 +34,11 @@
/* GC6 Entry/Exit state */
Name (GC6E, GC6_STATE_EXITED)
+/* Power State, GCOFF, GCON */
+#define GPU_POWER_STATE_OFF 0
+#define GPU_POWER_STATE_ON 1
+Name (GPPS, GPU_POWER_STATE_ON)
+
/* Defer GC6 entry / exit until D3-cold request */
Name (DFEN, 0)
/* Deferred GC6 Enter control */
@@ -129,6 +134,12 @@
/* GCOFF exit sequence */
Method (PGON, 0, Serialized)
{
+ If (GPPS == GPU_POWER_STATE_ON)
+ {
+ Printf ("PGON: GPU already on")
+ Return
+ }
+
/* Assert PERST# */
\_SB.PCI0.CTXS (GPIO_GPU_PERST_L)
@@ -158,17 +169,28 @@
/* Deassert PERST# */
\_SB.PCI0.STXS (GPIO_GPU_PERST_L)
+
+ GC6E = GC6_STATE_EXITED
+ GPPS = GPU_POWER_STATE_ON
+ Printf ("GPU Sequenced on")
}
/* GCOFF entry sequence */
Method (PGOF, 0, Serialized)
{
+ If (GPPS == GPU_POWER_STATE_OFF)
+ {
+ Printf ("GPU already off")
+ Return
+ }
+
/* Assert PERST# */
\_SB.PCI0.CTXS (GPIO_GPU_PERST_L)
Sleep (5)
/* All rails are about to go down */
\_SB.PCI0.CTXS (GPIO_GPU_ALLRAILS_PG)
+ Sleep (1)
/* Ramp down FBVDD (active-low) and let rail discharge to <10% */
\_SB.PCI0.STXS (GPIO_FBVDD_PWR_EN)
@@ -193,6 +215,9 @@
/* Ramp down 1.8V */
\_SB.PCI0.CTXS (GPIO_1V8_PWR_EN)
GPPL (GPIO_1V8_PG, 0, 20)
+
+ GPPS = GPU_POWER_STATE_OFF
+ Printf ("GPU sequenced off")
}
/* Handle deferred GC6 vs. poweron request */