MII_TG3_FET_PTEST
tg3_writephy(tp, MII_TG3_FET_PTEST, 0x12);
tg3_writephy(tp, MII_TG3_FET_PTEST, ptest);
tg3_writephy(tp, MII_TG3_FET_PTEST, ptest |
tg3_readphy(tp, MII_TG3_FET_PTEST, &val);