SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT
reg &= ~BIT(spi_get_chipselect(spi, 0) + SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT);
reg |= BIT(spi_get_chipselect(spi, 0) + SPIM_CTRL_CS_OVERRIDE_VAL_SHIFT);