SIOP_SCRATCHE
bus_space_write_1(sc->sc_c.sc_rt, sc->sc_c.sc_rh, SIOP_SCRATCHE, 0);
bus_space_write_1(sc->sc_c.sc_rt, sc->sc_c.sc_rh, SIOP_SCRATCHE + 2, 0);
sc->sc_c.sc_rh, SIOP_SCRATCHE);
sc->sc_c.sc_rh, SIOP_SCRATCHE, slot + 1);
sc->sc_c.sc_rh, SIOP_SCRATCHE, 0);