EVERGREEN_MASTER_UPDATE_LOCK
tmp = RREG32(EVERGREEN_MASTER_UPDATE_LOCK + crtc_offsets[i]);
WREG32(EVERGREEN_MASTER_UPDATE_LOCK + crtc_offsets[i], tmp);
tmp = RREG32(EVERGREEN_MASTER_UPDATE_LOCK + crtc_offsets[i]);
WREG32(EVERGREEN_MASTER_UPDATE_LOCK + crtc_offsets[i], tmp);