arch/blackfin/include/asm/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 static inline
  19 int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  20 {
  21         return 0;
  22 }
  23
  24 /*
  25  * Map a single buffer of the indicated size for DMA in streaming mode.
  26  * The 32-bit bus address to use is returned.
  27  *
  28  * Once the device is given the dma address, the device owns this memory
  29  * until either pci_unmap_single or pci_dma_sync_single is performed.
  30  */
  31 extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
  32                                  enum dma_data_direction direction);
  33
  34 static inline dma_addr_t
  35 dma_map_page(struct device *dev, struct page *page,
  36              unsigned long offset, size_t size,
  37              enum dma_data_direction dir)
  38 {
  39         return dma_map_single(dev, page_address(page) + offset, size, dir);
  40 }
  41
  42 /*
  43  * Unmap a single streaming mode DMA translation.  The dma_addr and size
  44  * must match what was provided for in a previous pci_map_single call.  All
  45  * other usages are undefined.
  46  *
  47  * After this call, reads by the cpu to the buffer are guarenteed to see
  48  * whatever the device wrote there.
  49  */
  50 extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
  51                           enum dma_data_direction direction);
  52
  53 static inline void
  54 dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
  55                enum dma_data_direction dir)
  56 {
  57         dma_unmap_single(dev, dma_addr, size, dir);
  58 }
  59
  60 /*
  61  * Map a set of buffers described by scatterlist in streaming
  62  * mode for DMA.  This is the scather-gather version of the
  63  * above pci_map_single interface.  Here the scatter gather list
  64  * elements are each tagged with the appropriate dma address
  65  * and length.  They are obtained via sg_dma_{address,length}(SG).
  66  *
  67  * NOTE: An implementation may be able to use a smaller number of
  68  *       DMA address/length pairs than there are SG table elements.
  69  *       (for example via virtual mapping capabilities)
  70  *       The routine returns the number of addr/length pairs actually
  71  *       used, at most nents.
  72  *
  73  * Device ownership issues as mentioned above for pci_map_single are
  74  * the same here.
  75  */
  76 extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
  77                       enum dma_data_direction direction);
  78
  79 /*
  80  * Unmap a set of streaming mode DMA translations.
  81  * Again, cpu read rules concerning calls here are the same as for
  82  * pci_unmap_single() above.
  83  */
  84 extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
  85                       int nhwentries, enum dma_data_direction direction);
  86
  87 static inline void dma_sync_single_for_cpu(struct device *dev,
  88                                         dma_addr_t handle, size_t size,
  89                                         enum dma_data_direction dir)
  90 {
  91 }
  92
  93 static inline void dma_sync_single_for_device(struct device *dev,
  94                                         dma_addr_t handle, size_t size,
  95                                         enum dma_data_direction dir)
  96 {
  97 }
  98
  99 static inline void dma_sync_sg_for_cpu(struct device *dev,
 100                                         struct scatterlist *sg,
 101                                         int nents, enum dma_data_direction dir)
 102 {
 103 }
 104
 105 static inline void dma_sync_sg_for_device(struct device *dev,
 106                                         struct scatterlist *sg,
 107                                         int nents, enum dma_data_direction dir)
 108 {
 109 }
 110
 111 #endif                          /* _BLACKFIN_DMA_MAPPING_H */