drm/i915/psr: Store pr_dpcd in intel_dp

We need pr_dpcd contents for early transport validity check on eDP Panel
Replay and in debugfs interface to dump out panel early transport
capability. Also remove unnecessarily printing out "Panel replay is not
supported by panel"

v2: commit message modified
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240528114455.175961-2-jouni.hogander@intel.com

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

@@ -1743,6 +1743,7 @@ struct intel_dp {
 	bool use_max_params;
 	u8 dpcd[DP_RECEIVER_CAP_SIZE];
 	u8 psr_dpcd[EDP_PSR_RECEIVER_CAP_SIZE];
+	u8 pr_dpcd;
 	u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS];
 	u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE];
 	u8 lttpr_common_caps[DP_LTTPR_COMMON_CAP_SIZE];

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

@@ -559,20 +559,10 @@ static void intel_dp_get_su_granularity(struct intel_dp *intel_dp)
 static void _panel_replay_init_dpcd(struct intel_dp *intel_dp)
 {
 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
-	u8 pr_dpcd = 0;
-
-	intel_dp->psr.sink_panel_replay_support = false;
-	drm_dp_dpcd_readb(&intel_dp->aux, DP_PANEL_REPLAY_CAP, &pr_dpcd);
-
-	if (!(pr_dpcd & DP_PANEL_REPLAY_SUPPORT)) {
-		drm_dbg_kms(&i915->drm,
-			    "Panel replay is not supported by panel\n");
-		return;
-	}
 
 	intel_dp->psr.sink_panel_replay_support = true;
 
-	if (pr_dpcd & DP_PANEL_REPLAY_SU_SUPPORT)
+	if (intel_dp->pr_dpcd & DP_PANEL_REPLAY_SU_SUPPORT)
 		intel_dp->psr.sink_panel_replay_su_support = true;
 
 	drm_dbg_kms(&i915->drm,
@@ -630,10 +620,13 @@ static void _psr_init_dpcd(struct intel_dp *intel_dp)
 
 void intel_psr_init_dpcd(struct intel_dp *intel_dp)
 {
-	_panel_replay_init_dpcd(intel_dp);
-
 	drm_dp_dpcd_read(&intel_dp->aux, DP_PSR_SUPPORT, intel_dp->psr_dpcd,
 			 sizeof(intel_dp->psr_dpcd));
+	drm_dp_dpcd_readb(&intel_dp->aux, DP_PANEL_REPLAY_CAP,
+			  &intel_dp->pr_dpcd);
+
+	if (intel_dp->pr_dpcd & DP_PANEL_REPLAY_SUPPORT)
+		_panel_replay_init_dpcd(intel_dp);
 
 	if (intel_dp->psr_dpcd[0])
 		_psr_init_dpcd(intel_dp);