UPPER_16_BITS
CP_WRITE(sc, CP_FIFO_BASE_HI, UPPER_16_BITS(fifo_start));
CP_WRITE(sc, CP_FIFO_END_HI, UPPER_16_BITS(fifo_end));
CP_WRITE(sc, CP_FIFO_HIWAT_HI, UPPER_16_BITS(fifo_hiwat));
CP_WRITE(sc, CP_FIFO_LOWAT_HI, UPPER_16_BITS(fifo_lowat));
CP_WRITE(sc, CP_FIFO_WRITE_PTR_HI, UPPER_16_BITS(fifo_start));
CP_WRITE(sc, CP_FIFO_READ_PTR_HI, UPPER_16_BITS(fifo_start));