DxMODE_VBLANK_ACK 3945 drivers/gpu/drm/radeon/r600.c 		WREG32(D1MODE_VBLANK_STATUS, DxMODE_VBLANK_ACK);
DxMODE_VBLANK_ACK 3949 drivers/gpu/drm/radeon/r600.c 		WREG32(D2MODE_VBLANK_STATUS, DxMODE_VBLANK_ACK);