dma_byte
writel_relaxed(dma_byte(pos), priv->base + RX_FQ_WR_ADDR);
writel_relaxed(dma_byte(pos), priv->base + RX_BQ_RD_ADDR);
writel_relaxed(dma_byte(pos), priv->base + TX_RQ_RD_ADDR);
writel_relaxed(dma_byte(pos), priv->base + TX_BQ_WR_ADDR);