[PATCH v2 2/2] drm/amd/display: Fix ASSR regression on embedded panels

Stylon Wang stylon.wang at amd.com
Wed Jul 21 04:25:24 UTC 2021


[Why]
Regression found in some embedded panels traces back to the earliest
upstreamed ASSR patch. The changed code flow are causing problems
with some panels.

[How]
- Change ASSR enabling code while preserving original code flow
  as much as possible
- Simplify the code on guarding with internal display flag

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=213779
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1620
Reviewed-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Stylon Wang <stylon.wang at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

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 cc62124b0b82..f56e061d35bc 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
@@ -1811,8 +1811,7 @@ bool perform_link_training_with_retries(
 					 */
 					panel_mode = DP_PANEL_MODE_DEFAULT;
 				}
-			} else
-				panel_mode = DP_PANEL_MODE_DEFAULT;
+			}
 		}
 #endif
 
@@ -4643,7 +4642,10 @@ enum dp_panel_mode dp_get_panel_mode(struct dc_link *link)
 		}
 	}
 
-	if (link->dpcd_caps.panel_mode_edp) {
+	if (link->dpcd_caps.panel_mode_edp &&
+		(link->connector_signal == SIGNAL_TYPE_EDP ||
+		 (link->connector_signal == SIGNAL_TYPE_DISPLAY_PORT &&
+		  link->is_internal_display))) {
 		return DP_PANEL_MODE_EDP;
 	}
 
-- 
2.32.0



More information about the amd-gfx mailing list