FSL DMA engine transfer to PCI memory

[Scott Wood]

On Mon, 24 Jan 2011 23:47:22 +0200
Felix Radensky <felix at embedded-sol.com> wrote:

> static int dma_transfer(struct dma_chan *chan, void *dst, void *src, 
> size_t len)
> {
>      int rc = 0;
>      dma_addr_t dma_src;
>      dma_addr_t dma_dst;
>      dma_cookie_t cookie;
>      struct completion cmp;
>      enum dma_status status;
>      enum dma_ctrl_flags flags = 0;
>      struct dma_device *dev = chan->device;
>      struct dma_async_tx_descriptor *tx = NULL;
>      unsigned long tmo = msecs_to_jiffies(FPGA_DMA_TIMEOUT_MS);
> 
>      dma_src = dma_map_single(dev->dev, src, len, DMA_TO_DEVICE);
>      if (dma_mapping_error(dev->dev, dma_src)) {
>          printk(KERN_ERR "Failed to map src for DMA\n");
>          return -EIO;
>      }
> 
>      dma_dst = (dma_addr_t)dst;

Why are you casting a virtual address to dma_addr_t?

> The destination address is PCI memory address returned by 
> pci_ioremap_bar().

You need the physical address.

-Scott