RSB_STAT_REG
stat = RSB_READ(sc, RSB_STAT_REG);
RSB_WRITE(sc, RSB_STAT_REG, stat & RSB_STAT_MASK);
sc->sc_stat |= RSB_READ(sc, RSB_STAT_REG);
RSB_WRITE(sc, RSB_STAT_REG,
RSB_WRITE(sc, RSB_STAT_REG,
RSB_READ(sc, RSB_STAT_REG) & RSB_STAT_MASK);