IMX_UTXD
bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, n);
bus_space_write_multi_1(iot, ioh, IMX_UTXD, sc->sc_tba, cc);
bus_space_write_4(iot, ioh, IMX_UTXD, c);
uartaddr[(IMX_UTXD/4)] = htole32(c);