MIO_TWS_SW_TWSI
octeon_xkphys_write_8(MIO_TWS_SW_TWSI, twsi.reg);
twsi.reg = octeon_xkphys_read_8(MIO_TWS_SW_TWSI);
octeon_xkphys_write_8(MIO_TWS_SW_TWSI, twsi.reg);
twsi.reg = octeon_xkphys_read_8(MIO_TWS_SW_TWSI);