ENET_EIR
status = HREAD4(sc, ENET_EIR);
HWRITE4(sc, ENET_EIR, status);
HWRITE4(sc, ENET_EIR, ENET_EIR_MII);
while(!(HREAD4(sc, ENET_EIR) & ENET_EIR_MII));
HWRITE4(sc, ENET_EIR, ENET_EIR_MII);
while(!(HREAD4(sc, ENET_EIR) & ENET_EIR_MII));
HWRITE4(sc, ENET_EIR, 0xffffffff);
HWRITE4(sc, ENET_EIR, 0xffffffff);