dev->mii.mdio_write = smsc75xx_mdio_write;
        dev->mii.phy_id_mask = 0x1f;
        dev->mii.reg_num_mask = 0x1f;
+       dev->mii.supports_gmii = 1;
        dev->mii.phy_id = SMSC75XX_INTERNAL_PHY_ID;
 
        /* reset phy and wait for reset to complete */
        smsc75xx_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE,
                ADVERTISE_ALL | ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP |
                ADVERTISE_PAUSE_ASYM);
+       smsc75xx_mdio_write(dev->net, dev->mii.phy_id, MII_CTRL1000,
+               ADVERTISE_1000FULL);
 
        /* read and write to clear phy interrupt status */
        ret = smsc75xx_mdio_read(dev->net, dev->mii.phy_id, PHY_INT_SRC);