On 25-03-19, 13:15, Kazuhiro Kasai wrote:
> Add Milbeaut AXI DMA controller. This DMA controller has
> only capable of memory to memory transfer.
Have you tested this with dmatest?
> +struct m10v_dma_chan {
> + struct dma_chan chan;
> + struct m10v_dma_device *mdmac;
> + void __iomem *regs;
> + int irq;
> + struct m10v_dma_desc mdesc;
So there is a *single* descriptor? Not a list??
> +static void m10v_xdmac_disable_dma(struct m10v_dma_device *mdmac)
> +{
> + unsigned int val;
> +
> + val = readl(mdmac->regs + M10V_XDACS);
> + val &= ~M10V_XDACS_XE;
> + val |= FIELD_PREP(M10V_XDACS_XE, 0);
> + writel(val, mdmac->regs + M10V_XDACS);
Why not create a modifyl() macro and use it here
> +static void m10v_xdmac_issue_pending(struct dma_chan *chan)
> +{
> + struct m10v_dma_chan *mchan = to_m10v_dma_chan(chan);
> +
> + m10v_xdmac_config_chan(mchan);
> +
> + m10v_xdmac_enable_chan(mchan);
You dont check if anything is already running or not?
> +static dma_cookie_t m10v_xdmac_tx_submit(struct dma_async_tx_descriptor *txd)
> +{
> + struct m10v_dma_chan *mchan = to_m10v_dma_chan(txd->chan);
> + dma_cookie_t cookie;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&mchan->lock, flags);
> + cookie = dma_cookie_assign(txd);
> + spin_unlock_irqrestore(&mchan->lock, flags);
> +
> + return cookie;
sounds like vchan_tx_submit() i think you can use virt-dma layer and then
get rid of artificial limit in driver and be able to queue up the txn on
dmaengine.
> +static struct dma_async_tx_descriptor *
> +m10v_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
> + dma_addr_t src, size_t len, unsigned long flags)
> +{
> + struct m10v_dma_chan *mchan = to_m10v_dma_chan(chan);
> +
> + dma_async_tx_descriptor_init(&mchan->mdesc.txd, chan);
> + mchan->mdesc.txd.tx_submit = m10v_xdmac_tx_submit;
> + mchan->mdesc.txd.callback = NULL;
> + mchan->mdesc.txd.flags = flags;
> + mchan->mdesc.txd.cookie = -EBUSY;
> +
> + mchan->mdesc.len = len;
> + mchan->mdesc.src = src;
> + mchan->mdesc.dst = dst;
> +
> + return &mchan->mdesc.txd;
So you support single descriptor and dont check if this has been already
configured. So I guess this has been tested by doing txn one at a time
and not submitted bunch of txn and wait for them to complete. Please fix
that to really enable dmaengine capabilities.
> +static int m10v_xdmac_remove(struct platform_device *pdev)
> +{
> + struct m10v_dma_chan *mchan;
> + struct m10v_dma_device *mdmac = platform_get_drvdata(pdev);
> + int i;
> +
> + m10v_xdmac_disable_dma(mdmac);
> +
> + for (i = 0; i < mdmac->channels; i++) {
> + mchan = &mdmac->mchan[i];
> + devm_free_irq(&pdev->dev, mchan->irq, mchan);
> + }
No call to dma_async_device_unregister()?
--
~Vinod
