drm/i915/tgl: Enabling DSC on Pipe A for TGL

DSC was not supported on Pipe A for previous platforms. Tigerlake onwards,
all the pipes support DSC. Hence, the DSC and FEC restriction on
Pipe A needs to be removed.

v2: Changes in the logic around removing the restriction around
    Pipe A (Manasi, Lucas)

Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Madhumitha Tolakanahalli Pradeep <madhumitha.tolakanahalli.pradeep@intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823004655.28905-1-madhumitha.tolakanahalli.pradeep@intel.com

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

@@ -1737,8 +1737,14 @@ static bool intel_dp_source_supports_fec(struct intel_dp *intel_dp,
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
 
-	return INTEL_GEN(dev_priv) >= 11 &&
-		pipe_config->cpu_transcoder != TRANSCODER_A;
+	/* On TGL, FEC is supported on all Pipes */
+	if (INTEL_GEN(dev_priv) >= 12)
+		return true;
+
+	if (IS_GEN(dev_priv, 11) && pipe_config->cpu_transcoder != TRANSCODER_A)
+		return true;
+
+	return false;
 }
 
 static bool intel_dp_supports_fec(struct intel_dp *intel_dp,
@@ -1753,8 +1759,15 @@ static bool intel_dp_source_supports_dsc(struct intel_dp *intel_dp,
 {
 	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
 
-	return INTEL_GEN(dev_priv) >= 10 &&
-		pipe_config->cpu_transcoder != TRANSCODER_A;
+	/* On TGL, DSC is supported on all Pipes */
+	if (INTEL_GEN(dev_priv) >= 12)
+		return true;
+
+	if (INTEL_GEN(dev_priv) >= 10 &&
+	    pipe_config->cpu_transcoder != TRANSCODER_A)
+		return true;
+
+	return false;
 }
 
 static bool intel_dp_supports_dsc(struct intel_dp *intel_dp,