RGMII0_SSR
ssr = bus_space_read_4(sc->sc_iot, sc->sc_rgmiih, RGMII0_SSR);
bus_space_write_4(sc->sc_iot, sc->sc_rgmiih, RGMII0_SSR, ssr);
ssr = bus_space_read_4(sc->sc_iot, sc->sc_rgmiih, RGMII0_SSR);
bus_space_write_4(sc->sc_iot, sc->sc_rgmiih, RGMII0_SSR, ssr);