LOONGSON_SPI_FIFO_REG
loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_FIFO_REG, *((*tx_buf)++));
loongson_spi_write_reg(loongson_spi, LOONGSON_SPI_FIFO_REG, 0);
*(*rx_buf)++ = loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_FIFO_REG);
loongson_spi_read_reg(loongson_spi, LOONGSON_SPI_FIFO_REG);