drm/i915/psr: Modify/Fix Wa_16013835468 and prepare for Wa_14015648006

Wa_16013835468 is a separate from Wa_14015648006 and needs to be
applied for display version 12. Fix this by removing all the
references to Wa_14015648006 and apply Wa_16013835468 according to
Bspec.

Also move workaround into separate function as a preparation for
Wa_14015648006 implementation.

Bspec: 55378

v3:
 - apply for display version 12 only
v2:
 - keep applying the wa in intel_psr_enable_source
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230329150703.432072-3-jouni.hogander@intel.com

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

@@ -1134,6 +1134,28 @@ static u32 wa_16013835468_bit_get(struct intel_dp *intel_dp)
 	}
 }
 
+/*
+ * Wa_16013835468
+ */
+static void wm_optimization_wa(struct intel_dp *intel_dp,
+			       const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
+	bool set_wa_bit = false;
+
+	/* Wa_16013835468 */
+	if (DISPLAY_VER(dev_priv) == 12)
+		set_wa_bit |= crtc_state->hw.adjusted_mode.crtc_vblank_start !=
+			crtc_state->hw.adjusted_mode.crtc_vdisplay;
+
+	if (set_wa_bit)
+		intel_de_rmw(dev_priv, GEN8_CHICKEN_DCPR_1,
+			     0, wa_16013835468_bit_get(intel_dp));
+	else
+		intel_de_rmw(dev_priv, GEN8_CHICKEN_DCPR_1,
+			     wa_16013835468_bit_get(intel_dp), 0);
+}
+
 static void intel_psr_enable_source(struct intel_dp *intel_dp,
 				    const struct intel_crtc_state *crtc_state)
 {
@@ -1175,15 +1197,8 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp,
 
 	/*
 	 * Wa_16013835468
-	 * Wa_14015648006
 	 */
-	if (IS_MTL_DISPLAY_STEP(dev_priv, STEP_A0, STEP_B0) ||
-	    IS_DISPLAY_VER(dev_priv, 12, 13)) {
-		if (crtc_state->hw.adjusted_mode.crtc_vblank_start !=
-		    crtc_state->hw.adjusted_mode.crtc_vdisplay)
-			intel_de_rmw(dev_priv, GEN8_CHICKEN_DCPR_1, 0,
-				     wa_16013835468_bit_get(intel_dp));
-	}
+	wm_optimization_wa(intel_dp, crtc_state);
 
 	if (intel_dp->psr.psr2_enabled) {
 		if (DISPLAY_VER(dev_priv) == 9)
@@ -1359,10 +1374,8 @@ static void intel_psr_disable_locked(struct intel_dp *intel_dp)
 
 	/*
 	 * Wa_16013835468
-	 * Wa_14015648006
 	 */
-	if (IS_MTL_DISPLAY_STEP(dev_priv, STEP_A0, STEP_B0) ||
-	    IS_DISPLAY_VER(dev_priv, 12, 13))
+	if (DISPLAY_VER(dev_priv) == 12)
 		intel_de_rmw(dev_priv, GEN8_CHICKEN_DCPR_1,
 			     wa_16013835468_bit_get(intel_dp), 0);