WPI_INTR
r = WPI_READ(sc, WPI_INTR);
WPI_WRITE(sc, WPI_INTR, r);
WPI_WRITE(sc, WPI_INTR, 0xffffffff);
WPI_WRITE(sc, WPI_INTR, 0xffffffff);
WPI_WRITE(sc, WPI_INTR, WPI_INTR_MASK);