RSPI_SPSCR
rspi_write8(rspi, 0, RSPI_SPSCR);
rspi_write8(rspi, 0, RSPI_SPSCR);
rspi_write8(rspi, 0, RSPI_SPSCR);
rspi_write8(rspi, 0, RSPI_SPSCR);
rspi_write8(rspi, i - 1, RSPI_SPSCR);
writeb(0x0, rspi->base + RSPI_SPSCR);