WMREG_RCTL
CSR_WRITE(l, WMREG_RCTL, 0);
CSR_WRITE(l, WMREG_RCTL, l->rctl);
mreg = CSR_READ(sc, WMREG_RCTL);
CSR_WRITE(sc, WMREG_RCTL, CSR_READ(sc, WMREG_RCTL) | RCTL_MPE);
mac_reg = CSR_READ(sc, WMREG_RCTL);
CSR_WRITE(sc, WMREG_RCTL, mac_reg);
CSR_WRITE(sc, WMREG_RCTL, sc->sc_rctl);
rctl = CSR_READ(sc, WMREG_RCTL);
CSR_WRITE(sc, WMREG_RCTL, rctl & ~RCTL_EN);
CSR_WRITE(sc, WMREG_RCTL, rctl | RCTL_EN);
CSR_WRITE(sc, WMREG_RCTL, rctl & ~RCTL_EN);
CSR_WRITE(sc, WMREG_RCTL, 0);
CSR_WRITE(sc, WMREG_RCTL, 0);