+ */
+static void zynqmp_dma_update_desc_to_ctrlr(struct zynqmp_dma_chan *chan,
+                                     struct zynqmp_dma_desc_sw *desc)
+{
+       dma_addr_t addr;
+
+       addr = desc->src_p;
+       writel(addr, chan->regs + ZYNQMP_DMA_SRC_START_LSB);
+       writel(upper_32_bits(addr), chan->regs + ZYNQMP_DMA_SRC_START_MSB);

Can we combine the two writes to a 64bit write.
It may be helpful on 64-bit systems.

+       addr = desc->dst_p;
+       writel(addr, chan->regs + ZYNQMP_DMA_DST_START_LSB);
+       writel(upper_32_bits(addr), chan->regs + ZYNQMP_DMA_DST_START_MSB);
+}