drm/radeon/kms: allow "invalid" DB formats as a means to disable DB

Signed-off-by: Marek Olšák <maraeo@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/evergreen_cs.c

@@ -961,13 +961,15 @@ static int evergreen_cs_track_check(struct radeon_cs_parser *p)
 
 	if (track->db_dirty) {
 		/* Check stencil buffer */
-		if (G_028800_STENCIL_ENABLE(track->db_depth_control)) {
+		if (G_028044_FORMAT(track->db_s_info) != V_028044_STENCIL_INVALID &&
+		    G_028800_STENCIL_ENABLE(track->db_depth_control)) {
 			r = evergreen_cs_track_validate_stencil(p);
 			if (r)
 				return r;
 		}
 		/* Check depth buffer */
-		if (G_028800_Z_ENABLE(track->db_depth_control)) {
+		if (G_028040_FORMAT(track->db_z_info) != V_028040_Z_INVALID &&
+		    G_028800_Z_ENABLE(track->db_depth_control)) {
 			r = evergreen_cs_track_validate_depth(p);
 			if (r)
 				return r;

drivers/gpu/drm/radeon/evergreend.h

@@ -1277,6 +1277,8 @@
 #define   S_028044_FORMAT(x)                           (((x) & 0x1) << 0)
 #define   G_028044_FORMAT(x)                           (((x) >> 0) & 0x1)
 #define   C_028044_FORMAT                              0xFFFFFFFE
+#define	    V_028044_STENCIL_INVALID			0
+#define	    V_028044_STENCIL_8				1
 #define   G_028044_TILE_SPLIT(x)                       (((x) >> 8) & 0x7)
 #define DB_Z_READ_BASE					0x28048
 #define DB_STENCIL_READ_BASE				0x2804c

drivers/gpu/drm/radeon/r600_cs.c

@@ -764,8 +764,10 @@ static int r600_cs_track_check(struct radeon_cs_parser *p)
 	}
 
 	/* Check depth buffer */
-	if (track->db_dirty && (G_028800_STENCIL_ENABLE(track->db_depth_control) ||
-		G_028800_Z_ENABLE(track->db_depth_control))) {
+	if (track->db_dirty &&
+	    G_028010_FORMAT(track->db_depth_info) != V_028010_DEPTH_INVALID &&
+	    (G_028800_STENCIL_ENABLE(track->db_depth_control) ||
+	     G_028800_Z_ENABLE(track->db_depth_control))) {
 		r = r600_cs_track_validate_db(p);
 		if (r)
 			return r;

drivers/gpu/drm/radeon/radeon_drv.c

@@ -59,9 +59,10 @@
  *   2.15.0 - add max_pipes query
  *   2.16.0 - fix evergreen 2D tiled surface calculation
  *   2.17.0 - add STRMOUT_BASE_UPDATE for r7xx
+ *   2.18.0 - r600-eg: allow "invalid" DB formats
  */
 #define KMS_DRIVER_MAJOR	2
-#define KMS_DRIVER_MINOR	17
+#define KMS_DRIVER_MINOR	18
 #define KMS_DRIVER_PATCHLEVEL	0
 int radeon_driver_load_kms(struct drm_device *dev, unsigned long flags);
 int radeon_driver_unload_kms(struct drm_device *dev);