drm/i915/psr: Fix for Panel Replay X granularity DPCD register handling

DP specification is saying value 0xff 0xff in PANEL REPLAY SELECTIVE UPDATE
X GRANULARITY CAPABILITY registers (0xb2 and 0xb3) means full-line
granularity. Take this into account when handling Panel Replay X
granularity informed by the panel.

Fixes: 1cc8546 ("drm/i915/psr: Use SU granularity information available in intel_connector")
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/7284
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patch.msgid.link/20260225074221.1744330-2-jouni.hogander@intel.com
(cherry picked from commit f5c8f82)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Author: hogander

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

@@ -1307,9 +1307,14 @@ static bool psr2_granularity_check(struct intel_crtc_state *crtc_state,
 	u16 sink_y_granularity = crtc_state->has_panel_replay ?
 		connector->dp.panel_replay_caps.su_y_granularity :
 		connector->dp.psr_caps.su_y_granularity;
-	u16 sink_w_granularity =  crtc_state->has_panel_replay ?
-		connector->dp.panel_replay_caps.su_w_granularity :
-		connector->dp.psr_caps.su_w_granularity;
+	u16 sink_w_granularity;
+
+	if (crtc_state->has_panel_replay)
+		sink_w_granularity = connector->dp.panel_replay_caps.su_w_granularity ==
+			DP_PANEL_REPLAY_FULL_LINE_GRANULARITY ?
+			crtc_hdisplay : connector->dp.panel_replay_caps.su_w_granularity;
+	else
+		sink_w_granularity = connector->dp.psr_caps.su_w_granularity;
 
 	/* PSR2 HW only send full lines so we only need to validate the width */
 	if (crtc_hdisplay % sink_w_granularity)