HARMONY_PNXTADD
WRITE_REG(sc, HARMONY_PNXTADD, nextaddr);
SYNC_REG(sc, HARMONY_PNXTADD, BUS_SPACE_BARRIER_WRITE);
WRITE_REG(sc, HARMONY_PNXTADD, nextaddr);
SYNC_REG(sc, HARMONY_PNXTADD, BUS_SPACE_BARRIER_WRITE);