On 02-06-21, 12:22, Sanjay R Mehta wrote: > +static void pt_do_cmd_complete(unsigned long data) > +{ > + struct pt_tasklet_data *tdata = (struct pt_tasklet_data *)data; > + struct pt_cmd *cmd = tdata->cmd; > + struct pt_cmd_queue *cmd_q = &cmd->pt->cmd_q; > + u32 tail; > + > + tail = lower_32_bits(cmd_q->qdma_tail + cmd_q->qidx * Q_DESC_SIZE); why extract tail in non error case? > +static int pt_issue_next_cmd(struct pt_dma_desc *desc) > +{ > + struct pt_passthru_engine *pt_engine; > + struct pt_dma_cmd *cmd; > + struct pt_device *pt; > + struct pt_cmd *pt_cmd; > + struct pt_cmd_queue *cmd_q; > + > + cmd = list_first_entry(&desc->cmdlist, struct pt_dma_cmd, entry); > + desc->issued_to_hw = 1; Why do you need this, the descriptor should be in vc.desc_issued list > +static void pt_free_active_cmd(struct pt_dma_desc *desc) > +{ > + struct pt_dma_cmd *cmd = NULL; > + > + if (desc->issued_to_hw) > + cmd = list_first_entry_or_null(&desc->cmdlist, struct pt_dma_cmd, > + entry); single line pls and use lists provided.. > +static struct pt_dma_desc *pt_handle_active_desc(struct pt_dma_chan *chan, > + struct pt_dma_desc *desc) > +{ > + struct dma_async_tx_descriptor *tx_desc; > + struct virt_dma_desc *vd; > + unsigned long flags; > + > + /* Loop over descriptors until one is found with commands */ > + do { > + if (desc) { > + /* Remove the DMA command from the list and free it */ > + pt_free_active_cmd(desc); > + if (!desc->issued_to_hw) { > + /* No errors, keep going */ > + if (desc->status != DMA_ERROR) > + return desc; > + /* Error, free remaining commands and move on */ > + pt_free_cmd_resources(desc->pt, > + &desc->cmdlist); single line again > +static struct pt_dma_desc *pt_alloc_dma_desc(struct pt_dma_chan *chan, > + unsigned long flags) > +{ > + struct pt_dma_desc *desc; > + > + desc = kmem_cache_zalloc(chan->pt->dma_desc_cache, GFP_NOWAIT); > + if (!desc) > + return NULL; > + > + vchan_tx_prep(&chan->vc, &desc->vd, flags); > + > + desc->pt = chan->pt; > + desc->issued_to_hw = 0; > + INIT_LIST_HEAD(&desc->cmdlist); why do you need your own list, the lists in vc should suffice? > +static int pt_resume(struct dma_chan *dma_chan) > +{ > + struct pt_dma_chan *chan = to_pt_chan(dma_chan); > + struct pt_dma_desc *desc = NULL; > + unsigned long flags; > + > + spin_lock_irqsave(&chan->vc.lock, flags); > + pt_start_queue(&chan->pt->cmd_q); > + desc = __pt_next_dma_desc(chan); > + spin_unlock_irqrestore(&chan->vc.lock, flags); > + > + /* If there was something active, re-start */ > + if (desc) > + pt_cmd_callback(desc, 0); this doesn't sound correct. In pause yoy stop the queue, so start of the queue should be done here... Why grab a descriptor? > +static int pt_terminate_all(struct dma_chan *dma_chan) > +{ > + struct pt_dma_chan *chan = to_pt_chan(dma_chan); > + > + vchan_free_chan_resources(&chan->vc); what about the descriptors, are you not going to clear the lists and free them.. > +int pt_dmaengine_register(struct pt_device *pt) > +{ > + struct pt_dma_chan *chan; > + struct dma_device *dma_dev = &pt->dma_dev; > + char *cmd_cache_name; > + char *desc_cache_name; > + int ret; > + > + pt->pt_dma_chan = devm_kzalloc(pt->dev, sizeof(*pt->pt_dma_chan), > + GFP_KERNEL); > + if (!pt->pt_dma_chan) > + return -ENOMEM; > + > + cmd_cache_name = devm_kasprintf(pt->dev, GFP_KERNEL, > + "%s-dmaengine-cmd-cache", > + pt->name); > + if (!cmd_cache_name) > + return -ENOMEM; > + > + pt->dma_cmd_cache = kmem_cache_create(cmd_cache_name, > + sizeof(struct pt_dma_cmd), > + sizeof(void *), > + SLAB_HWCACHE_ALIGN, NULL); > + if (!pt->dma_cmd_cache) > + return -ENOMEM; > + > + desc_cache_name = devm_kasprintf(pt->dev, GFP_KERNEL, > + "%s-dmaengine-desc-cache", > + pt->name); > + if (!desc_cache_name) { > + ret = -ENOMEM; > + goto err_cache; > + } > + > + pt->dma_desc_cache = kmem_cache_create(desc_cache_name, > + sizeof(struct pt_dma_desc), > + sizeof(void *), sizeof void ptr? > + SLAB_HWCACHE_ALIGN, NULL); > + if (!pt->dma_desc_cache) { > + ret = -ENOMEM; > + goto err_cache; > + } > + > + dma_dev->dev = pt->dev; > + dma_dev->src_addr_widths = DMA_SLAVE_BUSWIDTH_64_BYTES; > + dma_dev->dst_addr_widths = DMA_SLAVE_BUSWIDTH_64_BYTES; > + dma_dev->directions = DMA_MEM_TO_MEM; > + dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; > + dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); > + dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask); > + dma_cap_set(DMA_PRIVATE, dma_dev->cap_mask); Why DMA_PRIVATE ? this is a dma mempcy controller ... -- ~Vinod