RTC_ADDR
bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg);
bus_space_write_1(sc->sc_bst, sc->sc_bsh, RTC_ADDR, reg);
bus_space_write_1(sc->sc_bst, sc->sc_bsh, RTC_ADDR, reg);
if (ia->ia_addr != RTC_ADDR)