IMR0
bus_space_write_1(bst, bsh, offset + IMR0,
bus_space_write_1(bst, bsh, offset + IMR0, 0xff);
bus_space_write_1(bst, bsh, offset + IMR0, 0xff);
bus_space_write_1(sc->sc_bst, sc->sc_bsh, sc->sc_offset + IMR0, 0);