DW_SPI_SER
dw_writel(dws, DW_SPI_SER, BIT(spi_get_chipselect(spi, 0)));
dw_writel(dws, DW_SPI_SER, 0);
DW_SPI_DBGFS_REG("SER", DW_SPI_SER),
dw_writel(dws, DW_SPI_SER, 0xffff);
ser = dw_readl(dws, DW_SPI_SER);
dw_writel(dws, DW_SPI_SER, 0);
dw_writel(dws, DW_SPI_SER, 0);