RTSX_BIER
sc->sc_regs4[5] = READ4(sc, RTSX_BIER);
WRITE4(sc, RTSX_BIER, sc->sc_regs4[5]);
enabled = READ4(sc, RTSX_BIER);
WRITE4(sc, RTSX_BIER, 0);
WRITE4(sc, RTSX_BIER,