drm/i915: Configure DP 1.3+ protocol converted HDMI mode

DP 1.3 adds some extra control knobs for DP->HDMI protocol conversion.
Let's use that to configure the "HDMI mode" (ie. infoframes vs. not)
based on the capabilities of the sink.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200904115354.25336-13-ville.syrjala@linux.intel.comReviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

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

@@ -3470,6 +3470,7 @@ static void hsw_ddi_pre_enable_dp(struct intel_atomic_state *state,
 	intel_ddi_init_dp_buf_reg(encoder);
 	if (!is_mst)
 		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+	intel_dp_configure_protocol_converter(intel_dp);
 	intel_dp_sink_set_decompression_state(intel_dp, crtc_state,
 					      true);
 	intel_dp_sink_set_fec_ready(intel_dp, crtc_state);

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

@@ -3792,6 +3792,28 @@ static void intel_dp_enable_port(struct intel_dp *intel_dp,
 	intel_de_posting_read(dev_priv, intel_dp->output_reg);
 }
 
+void intel_dp_configure_protocol_converter(struct intel_dp *intel_dp)
+{
+	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+	u8 tmp;
+
+	if (intel_dp->dpcd[DP_DPCD_REV] < 0x13)
+		return;
+
+	if (!drm_dp_is_branch(intel_dp->dpcd))
+		return;
+
+	tmp = intel_dp->has_hdmi_sink ?
+		DP_HDMI_DVI_OUTPUT_CONFIG : 0;
+
+	if (drm_dp_dpcd_writeb(&intel_dp->aux,
+			       DP_PROTOCOL_CONVERTER_CONTROL_0, tmp) <= 0)
+		drm_dbg_kms(&i915->drm, "Failed to set protocol converter HDMI mode to %s\n",
+			    enableddisabled(intel_dp->has_hdmi_sink));
+
+	/* TODO: configure YCbCr 4:2:2/4:2:0 conversion */
+}
+
 static void intel_enable_dp(struct intel_atomic_state *state,
 			    struct intel_encoder *encoder,
 			    const struct intel_crtc_state *pipe_config,
@@ -3829,6 +3851,7 @@ static void intel_enable_dp(struct intel_atomic_state *state,
 	}
 
 	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+	intel_dp_configure_protocol_converter(intel_dp);
 	intel_dp_start_link_train(intel_dp);
 	intel_dp_stop_link_train(intel_dp);
 

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

@@ -51,6 +51,7 @@ int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp,
 int intel_dp_retrain_link(struct intel_encoder *encoder,
 			  struct drm_modeset_acquire_ctx *ctx);
 void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode);
+void intel_dp_configure_protocol_converter(struct intel_dp *intel_dp);
 void intel_dp_sink_set_decompression_state(struct intel_dp *intel_dp,
 					   const struct intel_crtc_state *crtc_state,
 					   bool enable);