drm/i915/sdvo: Make SDVO deal with HDMI pixel repeat

With SDVO the pipe config pixel_multiplier only concerns itself with the
data on the SDVO bus. Any HDMI specific pixel repeat must be handled by
the SDVO device itself. To do that simply configure the SDVO pixel
replication factor appropriately. We already set up the infoframe PRB
values correctly via the infoframe helpers.

There is no cap we can check for this. The spec says that 1X,2X,4X are
mandatory, anything else is optional. 1X and 2X are all we need so
we should be able to assume they work.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200108181242.13650-7-ville.syrjala@linux.intel.comReviewed-by: Imre Deak <imre.deak@intel.com>

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

@@ -944,6 +944,13 @@ static bool intel_sdvo_set_colorimetry(struct intel_sdvo *intel_sdvo,
 	return intel_sdvo_set_value(intel_sdvo, SDVO_CMD_SET_COLORIMETRY, &mode, 1);
 }
 
+static bool intel_sdvo_set_pixel_replication(struct intel_sdvo *intel_sdvo,
+					     u8 pixel_repeat)
+{
+	return intel_sdvo_set_value(intel_sdvo, SDVO_CMD_SET_PIXEL_REPLI,
+				    &pixel_repeat, 1);
+}
+
 static bool intel_sdvo_set_audio_state(struct intel_sdvo *intel_sdvo,
 				       u8 audio_state)
 {
@@ -1501,6 +1508,9 @@ static void intel_sdvo_pre_enable(struct intel_atomic_state *state,
 					   SDVO_COLORIMETRY_RGB220 :
 					   SDVO_COLORIMETRY_RGB256);
 		intel_sdvo_set_avi_infoframe(intel_sdvo, crtc_state);
+		intel_sdvo_set_pixel_replication(intel_sdvo,
+						 !!(adjusted_mode->flags &
+						    DRM_MODE_FLAG_DBLCLK));
 	} else
 		intel_sdvo_set_encode(intel_sdvo, SDVO_ENCODE_DVI);
 
@@ -1855,17 +1865,26 @@ intel_sdvo_mode_valid(struct drm_connector *connector,
 	struct intel_sdvo_connector *intel_sdvo_connector =
 		to_intel_sdvo_connector(connector);
 	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
+	bool has_hdmi_sink = intel_has_hdmi_sink(intel_sdvo, connector->state);
+	int clock = mode->clock;
 
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;
 
-	if (intel_sdvo->pixel_clock_min > mode->clock)
-		return MODE_CLOCK_LOW;
 
-	if (intel_sdvo->pixel_clock_max < mode->clock)
+	if (clock > max_dotclk)
 		return MODE_CLOCK_HIGH;
 
-	if (mode->clock > max_dotclk)
+	if (mode->flags & DRM_MODE_FLAG_DBLCLK) {
+		if (!has_hdmi_sink)
+			return MODE_CLOCK_LOW;
+		clock *= 2;
+	}
+
+	if (intel_sdvo->pixel_clock_min > clock)
+		return MODE_CLOCK_LOW;
+
+	if (intel_sdvo->pixel_clock_max < clock)
 		return MODE_CLOCK_HIGH;
 
 	if (IS_LVDS(intel_sdvo_connector)) {