1 files changed, 24 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 49b54f05d3cf..1aac59e83bff 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -136,6 +136,12 @@ intel_dp_link_required(struct drm_device *dev,
 }
 
 static int
+intel_dp_max_data_rate(int max_link_clock, int max_lanes)
+{
+        return (max_link_clock * max_lanes * 8) / 10;
+}
+
+static int
 intel_dp_mode_valid(struct drm_connector *connector,
                     struct drm_display_mode *mode)
 {
@@ -144,8 +150,11 @@ intel_dp_mode_valid(struct drm_connector *connector,
         int max_link_clock = intel_dp_link_clock(intel_dp_max_link_bw(intel_encoder));
         int max_lanes = intel_dp_max_lane_count(intel_encoder);
 
-        if (intel_dp_link_required(connector->dev, intel_encoder, mode->clock)
-                        > max_link_clock * max_lanes)
+        /* only refuse the mode on non eDP since we have seen some wierd eDP panels
+           which are outside spec tolerances but somehow work by magic */
+        if (!IS_eDP(intel_encoder) &&
+            (intel_dp_link_required(connector->dev, intel_encoder, mode->clock)
+             > intel_dp_max_data_rate(max_link_clock, max_lanes)))
                 return MODE_CLOCK_HIGH;
 
         if (mode->clock < 10000)
@@ -506,7 +515,7 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode,
 
         for (lane_count = 1; lane_count <= max_lane_count; lane_count <<= 1) {
                 for (clock = 0; clock <= max_clock; clock++) {
-                        int link_avail = intel_dp_link_clock(bws[clock]) * lane_count;
+                        int link_avail = intel_dp_max_data_rate(intel_dp_link_clock(bws[clock]), lane_count);
 
                         if (intel_dp_link_required(encoder->dev, intel_encoder, mode->clock)
                                         <= link_avail) {
@@ -521,6 +530,18 @@ intel_dp_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode,
                         }
                 }
         }
+
+        if (IS_eDP(intel_encoder)) {
+                /* okay we failed just pick the highest */
+                dp_priv->lane_count = max_lane_count;
+                dp_priv->link_bw = bws[max_clock];
+                adjusted_mode->clock = intel_dp_link_clock(dp_priv->link_bw);
+                DRM_DEBUG_KMS("Force picking display port link bw %02x lane "
+                              "count %d clock %d\n",
+                              dp_priv->link_bw, dp_priv->lane_count,
+                              adjusted_mode->clock);
+                return true;
+        }
         return false;
 }