MR1_IST
r &= ~(MR1_MF_MASK | MR1_IST | EMAC3_FDX);
r |= (MR1_MF_100MBS | MR1_IST);
r |= (EMAC3_FDX | MR1_IST);
sc->sc_mr1 &= ~(MR1_FDE | MR1_ILE | MR1_EIFC | MR1_MF_MASK | MR1_IST);
sc->sc_mr1 |= (MR1_FDE | MR1_EIFC | MR1_IST);
sc->sc_mr1 |= (MR1_MF_1000MBS | MR1_IST);
sc->sc_mr1 |= (MR1_MF_100MBS | MR1_IST);