[PATCH 5.12 151/384] drm/amd/display: Return invalid state if GPINT times out

[Greg Kroah-Hartman]

From: Wyatt Wood <wyatt.wood@xxxxxxx>

[ Upstream commit 8039bc7130ef4206a58e4dc288621bc97eba08eb ]

[Why]
GPINT timeout is causing PSR_STATE_0 to be returned when it shouldn't.
We must guarantee that PSR is fully disabled before doing hw programming
on driver-side.

[How]
Return invalid state if GPINT command times out. Let existing retry
logic send the GPINT until successful.

Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Wyatt Wood <wyatt.wood@xxxxxxx>
Reviewed-by: Anthony Koo <Anthony.Koo@xxxxxxx>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
index 69e34bef274c..febccb35ddad 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
@@ -81,13 +81,18 @@ static void dmub_psr_get_state(struct dmub_psr *dmub, enum dc_psr_state *state)
 {
 	struct dmub_srv *srv = dmub->ctx->dmub_srv->dmub;
 	uint32_t raw_state;
+	enum dmub_status status = DMUB_STATUS_INVALID;
 
 	// Send gpint command and wait for ack
-	dmub_srv_send_gpint_command(srv, DMUB_GPINT__GET_PSR_STATE, 0, 30);
-
-	dmub_srv_get_gpint_response(srv, &raw_state);
-
-	*state = convert_psr_state(raw_state);
+	status = dmub_srv_send_gpint_command(srv, DMUB_GPINT__GET_PSR_STATE, 0, 30);
+
+	if (status == DMUB_STATUS_OK) {
+		// GPINT was executed, get response
+		dmub_srv_get_gpint_response(srv, &raw_state);
+		*state = convert_psr_state(raw_state);
+	} else
+		// Return invalid state when GPINT times out
+		*state = 0xFF;
 }
 
 /*
-- 
2.30.2