MDIO_CTL
MDIO_WRITE4(sc, MDIO_CTL, ctl | CTL_READ);
MDIO_READ4(sc, MDIO_CTL);
MDIO_WRITE4(sc, MDIO_CTL, 0);
MDIO_WRITE4(sc, MDIO_CTL, (phy << 5) | reg);
MDIO_WRITE4(sc, MDIO_CTL, ctl);
MDIO_WRITE4(sc, MDIO_CTL, ctl | CTL_READ);
MDIO_READ4(sc, MDIO_CTL);
MDIO_WRITE4(sc, MDIO_CTL, 0);
MDIO_WRITE4(sc, MDIO_CTL, (phy << 5) | devad);
memac_write_4(sc, MDIO_CTL, ctl | MDIO_CTL_READ);
memac_write_4(sc, MDIO_CTL, ctl);