--- a/sys/dev/drm/radeon/radeon_combios.c
+++ b/sys/dev/drm/radeon/radeon_combios.c
@@ -2955,6 +2955,7 @@
 				case 0:
 					reg = (id & 0x1fff) * 4;
 					val = RBIOS32(index);
+					index += 4;
 					WREG32(reg, val);
 					break;
 				case 2: