From a9fb7c0790f815183773737dd88400ca328fb6d2 Mon Sep 17 00:00:00 2001
From: Yu-ting Shen <yu-tshen@amd.com>
Date: Tue, 19 Oct 2021 14:22:02 +0800
Subject: drm/amd/display: avoid link loss short pulse stuck the system
Git-commit: bca5bea4030d59b2d100c997b8044033247c1a99
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

[Why]
MST monitor sends link loss short pulse continuous but sink is
occupy by HDMI input to lead link training fail.

[How]
disable link once retraining fail.

Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Yu-ting Shen <yu-tshen@amd.com>
Reviewed-by: Wenjing Liu <Wenjing.Liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 2796bdd17de1..f14f71dd1aa9 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -4279,6 +4279,8 @@ void core_link_enable_stream(
 			 */
 			if (status != DC_FAIL_DP_LINK_TRAINING ||
 					pipe_ctx->stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST) {
+				if (false == stream->link->link_status.link_active)
+					disable_link(stream->link, pipe_ctx->stream->signal);
 				BREAK_TO_DEBUGGER();
 				return;
 			}
-- 
2.38.1