drm/i915: DP->HDMI TMDS clock limits vs. deep color

Account for the TMDS clock limits declared by the DFP
when determining what color depth we're going to use.

v2: Drop the reference to DP++ dongle since it's not handled here

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-17-ville.syrjala@linux.intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/display/intel_dp.c

@@ -1977,18 +1977,69 @@ static bool intel_dp_supports_dsc(struct intel_dp *intel_dp,
 		drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd);
 }
 
-static int intel_dp_compute_bpp(struct intel_dp *intel_dp,
-				struct intel_crtc_state *pipe_config)
+static bool intel_dp_hdmi_ycbcr420(struct intel_dp *intel_dp,
+				   const struct intel_crtc_state *crtc_state)
+{
+	return crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420;
+}
+
+static int intel_dp_hdmi_tmds_clock(struct intel_dp *intel_dp,
+				    const struct intel_crtc_state *crtc_state, int bpc)
+{
+	int clock = crtc_state->hw.adjusted_mode.crtc_clock * bpc / 8;
+
+	if (intel_dp_hdmi_ycbcr420(intel_dp, crtc_state))
+		clock /= 2;
+
+	return clock;
+}
+
+static bool intel_dp_hdmi_tmds_clock_valid(struct intel_dp *intel_dp,
+					   const struct intel_crtc_state *crtc_state, int bpc)
+{
+	int tmds_clock = intel_dp_hdmi_tmds_clock(intel_dp, crtc_state, bpc);
+
+	if (intel_dp->dfp.min_tmds_clock &&
+	    tmds_clock < intel_dp->dfp.min_tmds_clock)
+		return false;
+
+	if (intel_dp->dfp.max_tmds_clock &&
+	    tmds_clock > intel_dp->dfp.max_tmds_clock)
+		return false;
+
+	return true;
+}
+
+static bool intel_dp_hdmi_deep_color_possible(struct intel_dp *intel_dp,
+					      const struct intel_crtc_state *crtc_state,
+					      int bpc)
+{
+	bool has_hdmi_sink = intel_dp->has_hdmi_sink;
+
+	return intel_hdmi_deep_color_possible(crtc_state, bpc, has_hdmi_sink) &&
+		intel_dp_hdmi_tmds_clock_valid(intel_dp, crtc_state, bpc);
+}
+
+static int intel_dp_max_bpp(struct intel_dp *intel_dp,
+			    const struct intel_crtc_state *crtc_state)
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
 	struct intel_connector *intel_connector = intel_dp->attached_connector;
-	int bpp;
+	int bpp, bpc;
 
-	bpp = pipe_config->pipe_bpp;
+	bpc = crtc_state->pipe_bpp / 3;
 
 	if (intel_dp->dfp.max_bpc)
-		bpp = min(bpp, 3 * intel_dp->dfp.max_bpc);
+		bpc = min_t(int, bpc, intel_dp->dfp.max_bpc);
 
+	if (intel_dp->dfp.min_tmds_clock) {
+		for (; bpc >= 10; bpc -= 2) {
+			if (intel_dp_hdmi_deep_color_possible(intel_dp, crtc_state, bpc))
+				break;
+		}
+	}
+
+	bpp = bpc * 3;
 	if (intel_dp_is_edp(intel_dp)) {
 		/* Get bpp from vbt only for panels that dont have bpp in edid */
 		if (intel_connector->base.display_info.bpc == 0 &&
@@ -2310,7 +2361,7 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
 	limits.max_lane_count = intel_dp_max_lane_count(intel_dp);
 
 	limits.min_bpp = intel_dp_min_bpp(pipe_config);
-	limits.max_bpp = intel_dp_compute_bpp(intel_dp, pipe_config);
+	limits.max_bpp = intel_dp_max_bpp(intel_dp, pipe_config);
 
 	if (intel_dp_is_edp(intel_dp)) {
 		/*

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -2277,35 +2277,18 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
 	return intel_mode_valid_max_plane_size(dev_priv, mode);
 }
 
-static bool hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
-				     int bpc)
+bool intel_hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
+				    int bpc, bool has_hdmi_sink)
 {
-	struct drm_i915_private *dev_priv =
-		to_i915(crtc_state->uapi.crtc->dev);
 	struct drm_atomic_state *state = crtc_state->uapi.state;
 	struct drm_connector_state *connector_state;
 	struct drm_connector *connector;
-	const struct drm_display_mode *adjusted_mode =
-		&crtc_state->hw.adjusted_mode;
 	int i;
 
-	if (HAS_GMCH(dev_priv))
-		return false;
-
-	if (bpc == 10 && INTEL_GEN(dev_priv) < 11)
-		return false;
-
 	if (crtc_state->pipe_bpp < bpc * 3)
 		return false;
 
-	if (!crtc_state->has_hdmi_sink)
-		return false;
-
-	/*
-	 * HDMI deep color affects the clocks, so it's only possible
-	 * when not cloning with other encoder types.
-	 */
-	if (crtc_state->output_types != 1 << INTEL_OUTPUT_HDMI)
+	if (!has_hdmi_sink)
 		return false;
 
 	for_each_new_connector_in_state(state, connector, connector_state, i) {
@@ -2333,6 +2316,30 @@ static bool hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
 		}
 	}
 
+	return true;
+}
+
+static bool hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
+				     int bpc)
+{
+	struct drm_i915_private *dev_priv =
+		to_i915(crtc_state->uapi.crtc->dev);
+	const struct drm_display_mode *adjusted_mode =
+		&crtc_state->hw.adjusted_mode;
+
+	if (HAS_GMCH(dev_priv))
+		return false;
+
+	if (bpc == 10 && INTEL_GEN(dev_priv) < 11)
+		return false;
+
+	/*
+	 * HDMI deep color affects the clocks, so it's only possible
+	 * when not cloning with other encoder types.
+	 */
+	if (crtc_state->output_types != BIT(INTEL_OUTPUT_HDMI))
+		return false;
+
 	/* Display Wa_1405510057:icl,ehl */
 	if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 &&
 	    bpc == 10 && IS_GEN(dev_priv, 11) &&
@@ -2340,7 +2347,8 @@ static bool hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
 	     adjusted_mode->crtc_hblank_start) % 8 == 2)
 		return false;
 
-	return true;
+	return intel_hdmi_deep_color_possible(crtc_state, bpc,
+					      crtc_state->has_hdmi_sink);
 }
 
 static int

drivers/gpu/drm/i915/display/intel_hdmi.h

@@ -48,5 +48,7 @@ void intel_read_infoframe(struct intel_encoder *encoder,
 			  union hdmi_infoframe *frame);
 bool intel_hdmi_limited_color_range(const struct intel_crtc_state *crtc_state,
 				    const struct drm_connector_state *conn_state);
+bool intel_hdmi_deep_color_possible(const struct intel_crtc_state *crtc_state,
+				    int bpc, bool has_hdmi_sink);
 
 #endif /* __INTEL_HDMI_H__ */