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 #define dma_mapping_error
  19
  20 /*
  21  * Map a single buffer of the indicated size for DMA in streaming mode.
  22  * The 32-bit bus address to use is returned.
  23  *
  24  * Once the device is given the dma address, the device owns this memory
  25  * until either pci_unmap_single or pci_dma_sync_single is performed.
  26  */
  27 extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
  28                                  enum dma_data_direction direction);
  29
  30 static inline dma_addr_t
  31 dma_map_page(struct device *dev, struct page *page,
  32              unsigned long offset, size_t size,
  33              enum dma_data_direction dir)
  34 {
  35         return dma_map_single(dev, page_address(page) + offset, size, dir);
  36 }
  37
  38 /*
  39  * Unmap a single streaming mode DMA translation.  The dma_addr and size
  40  * must match what was provided for in a previous pci_map_single call.  All
  41  * other usages are undefined.
  42  *
  43  * After this call, reads by the cpu to the buffer are guarenteed to see
  44  * whatever the device wrote there.
  45  */
  46 extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
  47                           enum dma_data_direction direction);
  48
  49 static inline void
  50 dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
  51                enum dma_data_direction dir)
  52 {
  53         dma_unmap_single(dev, dma_addr, size, dir);
  54 }
  55
  56 /*
  57  * Map a set of buffers described by scatterlist in streaming
  58  * mode for DMA.  This is the scather-gather version of the
  59  * above pci_map_single interface.  Here the scatter gather list
  60  * elements are each tagged with the appropriate dma address
  61  * and length.  They are obtained via sg_dma_{address,length}(SG).
  62  *
  63  * NOTE: An implementation may be able to use a smaller number of
  64  *       DMA address/length pairs than there are SG table elements.
  65  *       (for example via virtual mapping capabilities)
  66  *       The routine returns the number of addr/length pairs actually
  67  *       used, at most nents.
  68  *
  69  * Device ownership issues as mentioned above for pci_map_single are
  70  * the same here.
  71  */
  72 extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
  73                       enum dma_data_direction direction);
  74
  75 /*
  76  * Unmap a set of streaming mode DMA translations.
  77  * Again, cpu read rules concerning calls here are the same as for
  78  * pci_unmap_single() above.
  79  */
  80 extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
  81                       int nhwentries, enum dma_data_direction direction);
  82
  83 #endif                          /* _BLACKFIN_DMA_MAPPING_H */