3 files changed, 24 insertions, 4 deletions
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 388a0635c38d..966d2f9c8c99 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -60,7 +60,14 @@
 
 enum {
 	LINK_RATE_REF_FREQ_IN_MHZ = 27,
-	PEAK_FACTOR_X1000 = 1006
+	PEAK_FACTOR_X1000 = 1006,
+	/*
+	* Some receivers fail to train on first try and are good
+	* on subsequent tries. 2 retries should be plenty. If we
+	* don't have a successful training then we don't expect to
+	* ever get one.
+	*/
+	LINK_TRAINING_MAX_VERIFY_RETRY = 2
 };
 
 /*******************************************************************************
@@ -760,7 +767,16 @@ bool dc_link_detect(struct dc_link *link, enum dc_detect_reason reason)
 				 */
 
 				/* deal with non-mst cases */
-				dp_verify_link_cap(link, &link->reported_link_cap);
+				for (i = 0; i < LINK_TRAINING_MAX_VERIFY_RETRY; i++) {
+					int fail_count = 0;
+
+					dp_verify_link_cap(link,
+							  &link->reported_link_cap,
+							  &fail_count);
+
+					if (fail_count == 0)
+						break;
+				}
 			}
 
 			/* HDMI-DVI Dongle */
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 9d901ca70588..58ee9aad13fb 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -1088,7 +1088,8 @@ static struct dc_link_settings get_max_link_cap(struct dc_link *link)
 
 bool dp_verify_link_cap(
 	struct dc_link *link,
-	struct dc_link_settings *known_limit_link_setting)
+	struct dc_link_settings *known_limit_link_setting,
+	int *fail_count)
 {
 	struct dc_link_settings max_link_cap = {0};
 	struct dc_link_settings cur_link_setting = {0};
@@ -1160,6 +1161,8 @@ bool dp_verify_link_cap(
 							skip_video_pattern);
 			if (status == LINK_TRAINING_SUCCESS)
 				success = true;
+			else
+				(*fail_count)++;
 		}
 
 		if (success)
diff --git a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
index 697b5ee73845..a37255c757e0 100644
--- a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dp.h
@@ -35,7 +35,8 @@ struct dc_link_settings;
 
 bool dp_verify_link_cap(
 	struct dc_link *link,
-	struct dc_link_settings *known_limit_link_setting);
+	struct dc_link_settings *known_limit_link_setting,
+	int *fail_count);
 
 bool dp_validate_mode_timing(
 	struct dc_link *link,