FAILED: patch "[PATCH] drm/amdgpu/display: use blanked rather than plane state for" failed to apply to 5.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b7f839d292948142eaab77cedd031aad0bfec872 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Tue, 2 Jun 2020 17:22:48 -0400
Subject: [PATCH] drm/amdgpu/display: use blanked rather than plane state for
 sync groups

We may end up with no planes set yet, depending on the ordering, but we
should have the proper blanking state which is either handled by either
DPG or TG depending on the hardware generation.  Check both to determine
the proper blanked state.

Bug: https://gitlab.freedesktop.org/drm/amd/issues/781
Fixes: 5fc0cbfad45648 ("drm/amd/display: determine if a pipe is synced by plane state")
Cc: nicholas.kazlauskas@amd.com
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 45cfb7c45566..b4e2053bca9f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -1016,9 +1016,17 @@ static void program_timing_sync(
 			}
 		}
 
-		/* set first pipe with plane as master */
+		/* set first unblanked pipe as master */
 		for (j = 0; j < group_size; j++) {
-			if (pipe_set[j]->plane_state) {
+			bool is_blanked;
+
+			if (pipe_set[j]->stream_res.opp->funcs->dpg_is_blanked)
+				is_blanked =
+					pipe_set[j]->stream_res.opp->funcs->dpg_is_blanked(pipe_set[j]->stream_res.opp);
+			else
+				is_blanked =
+					pipe_set[j]->stream_res.tg->funcs->is_blanked(pipe_set[j]->stream_res.tg);
+			if (!is_blanked) {
 				if (j == 0)
 					break;
 
@@ -1039,9 +1047,17 @@ static void program_timing_sync(
 				status->timing_sync_info.master = false;
 
 		}
-		/* remove any other pipes with plane as they have already been synced */
+		/* remove any other unblanked pipes as they have already been synced */
 		for (j = j + 1; j < group_size; j++) {
-			if (pipe_set[j]->plane_state) {
+			bool is_blanked;
+
+			if (pipe_set[j]->stream_res.opp->funcs->dpg_is_blanked)
+				is_blanked =
+					pipe_set[j]->stream_res.opp->funcs->dpg_is_blanked(pipe_set[j]->stream_res.opp);
+			else
+				is_blanked =
+					pipe_set[j]->stream_res.tg->funcs->is_blanked(pipe_set[j]->stream_res.tg);
+			if (!is_blanked) {
 				group_size--;
 				pipe_set[j] = pipe_set[group_size];
 				j--;