diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 189767cef356..2828ae612179 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -8588,7 +8588,9 @@ static void intel_atomic_prepare_plane_clear_colors(struct intel_atomic_state *s
 
 		/*
 		 * The layout of the fast clear color value expected by HW
-		 * (the DRM ABI requiring this value to be located in fb at offset 0 of plane#2):
+		 * (the DRM ABI requiring this value to be located in fb at
+		 * offset 0 of cc plane, plane #2 previous generations or
+		 * plane #1 for flat ccs):
 		 * - 4 x 4 bytes per-channel value
 		 *   (in surface type specific float/int format provided by the fb user)
 		 * - 8 bytes native color value used by the display
diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
index 3df6ef5ffec5..e94923e9dbb1 100644
--- a/drivers/gpu/drm/i915/display/intel_fb.c
+++ b/drivers/gpu/drm/i915/display/intel_fb.c
@@ -107,6 +107,21 @@ static const struct drm_format_info gen12_ccs_cc_formats[] = {
 	  .hsub = 1, .vsub = 1, .has_alpha = true },
 };
 
+static const struct drm_format_info gen12_flat_ccs_cc_formats[] = {
+	{ .format = DRM_FORMAT_XRGB8888, .depth = 24, .num_planes = 2,
+	  .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
+	  .hsub = 1, .vsub = 1, },
+	{ .format = DRM_FORMAT_XBGR8888, .depth = 24, .num_planes = 2,
+	  .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
+	  .hsub = 1, .vsub = 1, },
+	{ .format = DRM_FORMAT_ARGB8888, .depth = 32, .num_planes = 2,
+	  .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
+	  .hsub = 1, .vsub = 1, .has_alpha = true },
+	{ .format = DRM_FORMAT_ABGR8888, .depth = 32, .num_planes = 2,
+	  .char_per_block = { 4, 0 }, .block_w = { 1, 2 }, .block_h = { 1, 1 },
+	  .hsub = 1, .vsub = 1, .has_alpha = true },
+};
+
 struct intel_modifier_desc {
 	u64 modifier;
 	struct {
@@ -150,6 +165,8 @@ static const struct intel_modifier_desc intel_modifiers[] = {
 		.plane_caps = INTEL_PLANE_CAP_TILING_4 | INTEL_PLANE_CAP_CCS_RC_CC,
 
 		.ccs.cc_planes = BIT(1),
+
+		FORMAT_OVERRIDE(gen12_flat_ccs_cc_formats),
 	}, {
 		.modifier = I915_FORMAT_MOD_4_TILED_DG2_RC_CCS,
 		.display_ver = { 13, 13 },
@@ -399,17 +416,13 @@ bool intel_fb_plane_supports_modifier(struct intel_plane *plane, u64 modifier)
 static bool format_is_yuv_semiplanar(const struct intel_modifier_desc *md,
 				     const struct drm_format_info *info)
 {
-	int yuv_planes;
-
 	if (!info->is_yuv)
 		return false;
 
-	if (plane_caps_contain_any(md->plane_caps, INTEL_PLANE_CAP_CCS_MASK))
-		yuv_planes = 4;
+	if (hweight8(md->ccs.planar_aux_planes) == 2)
+		return info->num_planes == 4;
 	else
-		yuv_planes = 2;
-
-	return info->num_planes == yuv_planes;
+		return info->num_planes == 2;
 }
 
 /**
@@ -534,12 +547,13 @@ static unsigned int gen12_ccs_aux_stride(struct intel_framebuffer *fb, int ccs_p
 
 int skl_main_to_aux_plane(const struct drm_framebuffer *fb, int main_plane)
 {
+	const struct intel_modifier_desc *md = lookup_modifier(fb->modifier);
 	struct drm_i915_private *i915 = to_i915(fb->dev);
 
-	if (intel_fb_is_ccs_modifier(fb->modifier))
+	if (md->ccs.packed_aux_planes | md->ccs.planar_aux_planes)
 		return main_to_ccs_plane(fb, main_plane);
 	else if (DISPLAY_VER(i915) < 11 &&
-		 intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier))
+		 format_is_yuv_semiplanar(md, fb->format))
 		return 1;
 	else
 		return 0;
diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index b4dced1907c5..18e50583abaa 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -1176,8 +1176,10 @@ skl_plane_update_arm(struct intel_plane *plane,
 	intel_de_write_fw(dev_priv, PLANE_OFFSET(pipe, plane_id),
 			  PLANE_OFFSET_Y(y) | PLANE_OFFSET_X(x));
 
-	intel_de_write_fw(dev_priv, PLANE_AUX_DIST(pipe, plane_id),
-			  skl_plane_aux_dist(plane_state, color_plane));
+	/* FLAT CCS doesn't need to program AUX_DIST */
+	if (!HAS_FLAT_CCS(dev_priv))
+		intel_de_write_fw(dev_priv, PLANE_AUX_DIST(pipe, plane_id),
+				  skl_plane_aux_dist(plane_state, color_plane));
 
 	if (DISPLAY_VER(dev_priv) < 11)
 		intel_de_write_fw(dev_priv, PLANE_AUX_OFFSET(pipe, plane_id),
@@ -1557,9 +1559,10 @@ static int skl_check_main_surface(struct intel_plane_state *plane_state)
 
 	/*
 	 * CCS AUX surface doesn't have its own x/y offsets, we must make sure
-	 * they match with the main surface x/y offsets.
+	 * they match with the main surface x/y offsets. On DG2
+	 * there's no aux plane on fb so skip this checking.
 	 */
-	if (intel_fb_is_ccs_modifier(fb->modifier)) {
+	if (intel_fb_is_ccs_modifier(fb->modifier) && aux_plane) {
 		while (!skl_check_main_ccs_coordinates(plane_state, x, y,
 						       offset, aux_plane)) {
 			if (offset == 0)
@@ -1603,6 +1606,8 @@ static int skl_check_nv12_aux_surface(struct intel_plane_state *plane_state)
 	const struct drm_framebuffer *fb = plane_state->hw.fb;
 	unsigned int rotation = plane_state->hw.rotation;
 	int uv_plane = 1;
+	int ccs_plane = intel_fb_is_ccs_modifier(fb->modifier) ?
+			skl_main_to_aux_plane(fb, uv_plane) : 0;
 	int max_width = intel_plane_max_width(plane, fb, uv_plane, rotation);
 	int max_height = intel_plane_max_height(plane, fb, uv_plane, rotation);
 	int x = plane_state->uapi.src.x1 >> 17;
@@ -1623,8 +1628,7 @@ static int skl_check_nv12_aux_surface(struct intel_plane_state *plane_state)
 	offset = intel_plane_compute_aligned_offset(&x, &y,
 						    plane_state, uv_plane);
 
-	if (intel_fb_is_ccs_modifier(fb->modifier)) {
-		int ccs_plane = main_to_ccs_plane(fb, uv_plane);
+	if (ccs_plane) {
 		u32 aux_offset = plane_state->view.color_plane[ccs_plane].offset;
 		u32 alignment = intel_surf_alignment(fb, uv_plane);
 
