diff --git a/include/drm/radeon_drm.h b/include/drm/radeon_drm.h
index 10f8b53..e95a86b 100644
--- a/include/drm/radeon_drm.h
+++ b/include/drm/radeon_drm.h
@@ -906,6 +906,7 @@
 #define RADEON_INFO_ACCEL_WORKING2	0x05
 #define RADEON_INFO_TILING_CONFIG	0x06
 #define RADEON_INFO_WANT_HYPERZ		0x07
+#define RADEON_INFO_WANT_CMASK		0x08 /* get access to CMASK on r300 */
 
 struct drm_radeon_info {
 	uint32_t		request;