drm_atomic_get_existing_crtc_state
crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
crtc_state = drm_atomic_get_existing_crtc_state(state->state,
crtc_state = drm_atomic_get_existing_crtc_state(state, plane_state->crtc);