Skip to contentSkip to conversation

FAILED: patch "[PATCH] drm/radeon/mst: fix regression in lane/link handling." failed to apply to 4.4-stable tree

PATCH [email protected] 1 participant 1 message Apr 10, 2016

Subsystems (3)
Stable branch DRM drivers Radeon and amdgpu DRM drivers
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.4-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 <[email protected]>.

thanks,

greg k-h

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

Quoted 1 line

From b36f7d26a7fdc0b07b1217368ee09bb8560269f8 Mon Sep 17 00:00:00 2001

From: Dave Airlie <[email protected]>
Date: Tue, 22 Mar 2016 09:38:18 +1000
Subject: [PATCH] drm/radeon/mst: fix regression in lane/link handling.

The function this used changed in
092c96a8ab9d1bd60ada2ed385cc364ce084180e
drm/radeon: fix dp link rate selection (v2)

However for MST we should just always train to the max link/rate. Though we probably need to limit this for future hw, in theory radeon won't support it.

This fixes my 30" monitor with MST enabled.

Cc [email protected] # v4.4
Signed-off-by Dave Airlie <[email protected]>
Signed-off-by Alex Deucher <[email protected]>
drivers/gpu/drm/radeon/radeon_dp_mst.c +2 -10
index df7a1719c841..9d210bbcab50 100644
@@ -525,17 +525,9 @@ static bool radeon_mst_mode_fixup(struct drm_encoder *encoder,
 	drm_mode_set_crtcinfo(adjusted_mode, 0);
 	{
 	  struct radeon_connector_atom_dig *dig_connector;
-	  int ret;
-
 	  dig_connector = mst_enc->connector->con_priv;
-	  ret = radeon_dp_get_dp_link_config(&mst_enc->connector->base,
-					     dig_connector->dpcd, adjusted_mode->clock,
-					     &dig_connector->dp_lane_count,
-					     &dig_connector->dp_clock);
-	  if (ret) {
-		  dig_connector->dp_lane_count = 0;
-		  dig_connector->dp_clock = 0;
-	  }
+	  dig_connector->dp_lane_count = drm_dp_max_lane_count(dig_connector->dpcd);
+	  dig_connector->dp_clock = drm_dp_max_link_rate(dig_connector->dpcd);
 	  DRM_DEBUG_KMS("dig clock %p %d %d\n", dig_connector,
 			dig_connector->dp_lane_count, dig_connector->dp_clock);
 	}