On Monday 26 October 2015 22:14:58 John Garry wrote: > + /* > + * DMA-map SMP request, response buffers > + */ > + /* req */ > + sg_req = &task->smp_task.smp_req; > + elem = dma_map_sg(dev, sg_req, 1, DMA_TO_DEVICE); > + if (!elem) > + return -ENOMEM; > + req_len = sg_dma_len(sg_req); > + req_dma_addr = sg_dma_address(sg_req); If you only use the first element, could you just use dma_map_single()? > + hdr->cmd_table_addr_lo = cpu_to_le32(lower_32_bits(req_dma_addr)); > + hdr->cmd_table_addr_hi = cpu_to_le32(upper_32_bits(req_dma_addr)); > + > + hdr->sts_buffer_addr_lo = > + cpu_to_le32(lower_32_bits(slot->status_buffer_dma)); > + hdr->sts_buffer_addr_hi = > + cpu_to_le32(upper_32_bits(slot->status_buffer_dma)); > + > I see these a lot in your code. Could you replace this wit hdr->cmd_table_addr = cpu_to_le64(req_dma_addr); and so on? That would be much more readable. Or are the two __le32 variables swapped? If so, you could add a small helper function like static inline __le64 cpu_to_le64_wordswapped(u64 val) { return cpu_to_le64(val >> 32 | val << 32); } Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html