From: Ray Wu <ray.wu@amd.com>
Date: Fri, 3 Jul 2026 01:14:49 +0000 (+0800)
Subject: drm/amd/display: Increase HDMI AV mute wait from 2 to 3 frames
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c216b39fbbc4b007fd6984cffd85039d49a55154;p=thirdparty%2Flinux.git

drm/amd/display: Increase HDMI AV mute wait from 2 to 3 frames

Some HDMI sinks need additional GCP packets to properly process the
mute state before the timing generator is disabled, especially after
link re-establishment with HDMI 2.0 scrambling enabled. Waiting for
only 2 frames is insufficient for certain monitor firmware, resulting
in garbled display output on resume from suspend.

Increase the AV mute wait in dcn30_set_avmute() from 2 to 3 frames
to ensure the sink receives enough GCP packets.

Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/5167
Assisted-by: Cursor:Claude-Opus-4.6
Reviewed-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 0c0d5174b09640d8b560764aa5a177630e076e93)
Cc: stable@vger.kernel.org
---

diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
index a7c85a2302ab..2d3587a31bc8 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
@@ -847,13 +847,19 @@ void dcn30_set_avmute(struct pipe_ctx *pipe_ctx, bool enable)
 				pipe_ctx->stream_res.stream_enc,
 				enable);
 
-		/* Wait for two frame to make sure AV mute is sent out */
+		/* Wait for three frames to make sure AV mute is sent out.
+		 * Some HDMI sinks need additional GCP packets to properly
+		 * process the mute state, especially after link re-establishment
+		 * with HDMI 2.0 scrambling enabled.
+		 */
 		if (enable && pipe_ctx->stream_res.tg->funcs->is_tg_enabled(pipe_ctx->stream_res.tg)) {
+			int i;
+
 			pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VACTIVE);
-			pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VBLANK);
-			pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VACTIVE);
-			pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VBLANK);
-			pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VACTIVE);
+			for (i = 0; i < 3; i++) {
+				pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VBLANK);
+				pipe_ctx->stream_res.tg->funcs->wait_for_state(pipe_ctx->stream_res.tg, CRTC_STATE_VACTIVE);
+			}
 		}
 	}
 }