1 files changed, 30 insertions, 8 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 6b1c9a27c27..1aac59e83bf 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;
 }
 
@@ -576,7 +597,7 @@ intel_dp_set_m_n(struct drm_crtc *crtc, struct drm_display_mode *mode,
 		struct intel_encoder *intel_encoder;
 		struct intel_dp_priv *dp_priv;
 
-		if (!encoder || encoder->crtc != crtc)
+		if (encoder->crtc != crtc)
 			continue;
 
 		intel_encoder = enc_to_intel_encoder(encoder);
@@ -675,10 +696,9 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
 	dp_priv->link_configuration[1] = dp_priv->lane_count;
 
 	/*
-	 * Check for DPCD version > 1.1,
-	 * enable enahanced frame stuff in that case
+	 * Check for DPCD version > 1.1 and enhanced framing support
 	 */
-	if (dp_priv->dpcd[0] >= 0x11) {
+	if (dp_priv->dpcd[0] >= 0x11 && (dp_priv->dpcd[2] & DP_ENHANCED_FRAME_CAP)) {
 		dp_priv->link_configuration[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
 		dp_priv->DP |= DP_ENHANCED_FRAMING;
 	}
@@ -1208,6 +1228,8 @@ ironlake_dp_detect(struct drm_connector *connector)
 		if (dp_priv->dpcd[0] != 0)
 			status = connector_status_connected;
 	}
+	DRM_DEBUG_KMS("DPCD: %hx%hx%hx%hx\n", dp_priv->dpcd[0],
+		      dp_priv->dpcd[1], dp_priv->dpcd[2], dp_priv->dpcd[3]);
 	return status;
 }
 
@@ -1352,7 +1374,7 @@ intel_trans_dp_port_sel (struct drm_crtc *crtc)
 	struct intel_encoder *intel_encoder = NULL;
 
 	list_for_each_entry(encoder, &mode_config->encoder_list, head) {
-		if (!encoder || encoder->crtc != crtc)
+		if (encoder->crtc != crtc)
 			continue;
 
 		intel_encoder = enc_to_intel_encoder(encoder);