include/asm-blackfin/dma-mapping.h

   1 #ifndef _BLACKFIN_DMA_MAPPING_H
   2 #define _BLACKFIN_DMA_MAPPING_H
   3
   4 #include <asm/scatterlist.h>
   5
   6 void dma_alloc_init(unsigned long start, unsigned long end);
   7 void *dma_alloc_coherent(struct device *dev, size_t size,
   8                          dma_addr_t *dma_handle, gfp_t gfp);
   9 void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
  10                        dma_addr_t dma_handle);
  11
  12 /*
  13  * Now for the API extensions over the pci_ one
  14  */
  15 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
  16 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
  17
  18 /*
  19  * Map a single buffer of the indicated size for DMA in streaming mode.
  20  * The 32-bit bus address to use is returned.
  21  *
  22  * Once the device is given the dma address, the device owns this memory
  23  * until either pci_unmap_single or pci_dma_sync_single is performed.
  24  */
  25 extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
  26                                  enum dma_data_direction direction);
  27
  28 /*
  29  * Unmap a single streaming mode DMA translation.  The dma_addr and size
  30  * must match what was provided for in a previous pci_map_single call.  All
  31  * other usages are undefined.
  32  *
  33  * After this call, reads by the cpu to the buffer are guarenteed to see
  34  * whatever the device wrote there.
  35  */
  36 extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
  37                           enum dma_data_direction direction);
  38
  39 /*
  40  * Map a set of buffers described by scatterlist in streaming
  41  * mode for DMA.  This is the scather-gather version of the
  42  * above pci_map_single interface.  Here the scatter gather list
  43  * elements are each tagged with the appropriate dma address
  44  * and length.  They are obtained via sg_dma_{address,length}(SG).
  45  *
  46  * NOTE: An implementation may be able to use a smaller number of
  47  *       DMA address/length pairs than there are SG table elements.
  48  *       (for example via virtual mapping capabilities)
  49  *       The routine returns the number of addr/length pairs actually
  50  *       used, at most nents.
  51  *
  52  * Device ownership issues as mentioned above for pci_map_single are
  53  * the same here.
  54  */
  55 extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
  56                       enum dma_data_direction direction);
  57
  58 /*
  59  * Unmap a set of streaming mode DMA translations.
  60  * Again, cpu read rules concerning calls here are the same as for
  61  * pci_unmap_single() above.
  62  */
  63 extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
  64                       int nhwentries, enum dma_data_direction direction);
  65
  66 #endif                          /* _BLACKFIN_DMA_MAPPING_H */