drm/i915: Assert {pre,post}_csc_lut were assigned sensibly

Since we now have the extra step from hw.(de)gamma_lut into
{pre,post}_csc_lut let's make sure we didn't forget to assign
them appropriately. Ie. basically making sure intel_color_check()
was called when necessary (and that it did its job suitable well).
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221024161514.5340-4-ville.syrjala@linux.intel.com

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

@@ -1359,6 +1359,26 @@ static u32 i9xx_gamma_mode(struct intel_crtc_state *crtc_state)
 		return GAMMA_MODE_MODE_10BIT; /* i965+ only */
 }
 
+void intel_color_assert_luts(const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev);
+
+	/* make sure {pre,post}_csc_lut were correctly assigned */
+	if (DISPLAY_VER(i915) >= 10 || HAS_GMCH(i915)) {
+		drm_WARN_ON(&i915->drm,
+			    crtc_state->pre_csc_lut != crtc_state->hw.degamma_lut);
+		drm_WARN_ON(&i915->drm,
+			    crtc_state->post_csc_lut != crtc_state->hw.gamma_lut);
+	} else {
+		drm_WARN_ON(&i915->drm,
+			    crtc_state->pre_csc_lut != crtc_state->hw.degamma_lut &&
+			    crtc_state->pre_csc_lut != crtc_state->hw.gamma_lut);
+		drm_WARN_ON(&i915->drm,
+			    crtc_state->post_csc_lut != crtc_state->hw.degamma_lut &&
+			    crtc_state->post_csc_lut != crtc_state->hw.gamma_lut);
+	}
+}
+
 static void intel_assign_luts(struct intel_crtc_state *crtc_state)
 {
 	drm_property_replace_blob(&crtc_state->pre_csc_lut,

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

@@ -24,5 +24,6 @@ int intel_color_get_gamma_bit_precision(const struct intel_crtc_state *crtc_stat
 bool intel_color_lut_equal(struct drm_property_blob *blob1,
 			   struct drm_property_blob *blob2,
 			   u32 gamma_mode, u32 bit_precision);
+void intel_color_assert_luts(const struct intel_crtc_state *crtc_state);
 
 #endif /* __INTEL_COLOR_H__ */

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

@@ -6886,6 +6886,8 @@ static int intel_atomic_check(struct drm_device *dev,
 
 	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
 					    new_crtc_state, i) {
+		intel_color_assert_luts(new_crtc_state);
+
 		ret = intel_async_flip_check_hw(state, crtc);
 		if (ret)
 			goto fail;