RGE_DTCCR_LO
RGE_WRITE_4(sc, RGE_DTCCR_LO, RGE_ADDR_LO(addr));
bus_space_barrier(sc->rge_btag, sc->rge_bhandle, RGE_DTCCR_LO, 4,
RGE_WRITE_4(sc, RGE_DTCCR_LO, RGE_ADDR_LO(addr) | RGE_DTCCR_CMD);
bus_space_barrier(sc->rge_btag, sc->rge_bhandle, RGE_DTCCR_LO, 4,
reg = RGE_READ_4(sc, RGE_DTCCR_LO);
RGE_DTCCR_LO, 4, BUS_SPACE_BARRIER_READ);