drm/i915: Introduce g4x_hdmi_compute_config()

Start pulling some of the more platform specific things out from
intel_hdmi_compute_config(). has_pch_encoder is clearly one
such thing.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221107194604.15227-2-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/g4x_hdmi.c

@@ -79,6 +79,18 @@ static bool intel_hdmi_get_hw_state(struct intel_encoder *encoder,
 	return ret;
 }
 
+static int g4x_hdmi_compute_config(struct intel_encoder *encoder,
+				   struct intel_crtc_state *crtc_state,
+				   struct drm_connector_state *conn_state)
+{
+	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
+
+	if (HAS_PCH_SPLIT(i915))
+		crtc_state->has_pch_encoder = true;
+
+	return intel_hdmi_compute_config(encoder, crtc_state, conn_state);
+}
+
 static void intel_hdmi_get_config(struct intel_encoder *encoder,
 				  struct intel_crtc_state *pipe_config)
 {
@@ -544,7 +556,7 @@ void g4x_hdmi_init(struct drm_i915_private *dev_priv,
 			 "HDMI %c", port_name(port));
 
 	intel_encoder->hotplug = intel_hdmi_hotplug;
-	intel_encoder->compute_config = intel_hdmi_compute_config;
+	intel_encoder->compute_config = g4x_hdmi_compute_config;
 	if (HAS_PCH_SPLIT(dev_priv)) {
 		intel_encoder->disable = pch_disable_hdmi;
 		intel_encoder->post_disable = pch_post_disable_hdmi;

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

@@ -2258,9 +2258,6 @@ int intel_hdmi_compute_config(struct intel_encoder *encoder,
 	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
 		pipe_config->pixel_multiplier = 2;
 
-	if (HAS_PCH_SPLIT(dev_priv) && !HAS_DDI(dev_priv))
-		pipe_config->has_pch_encoder = true;
-
 	pipe_config->has_audio =
 		intel_hdmi_has_audio(encoder, pipe_config, conn_state);