LXR linux/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
   6void dma_alloc_init(unsigned long start, unsigned long end);
   7void *dma_alloc_coherent(struct device *dev, size_t size,
   8                         dma_addr_t *dma_handle, gfp_t gfp);
   9void 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 */
  27extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
  28                                 enum dma_data_direction direction);
  29
  30/*
  31 * Unmap a single streaming mode DMA translation.  The dma_addr and size
  32 * must match what was provided for in a previous pci_map_single call.  All
  33 * other usages are undefined.
  34 *
  35 * After this call, reads by the cpu to the buffer are guarenteed to see
  36 * whatever the device wrote there.
  37 */
  38extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
  39                          enum dma_data_direction direction);
  40
  41/*
  42 * Map a set of buffers described by scatterlist in streaming
  43 * mode for DMA.  This is the scather-gather version of the
  44 * above pci_map_single interface.  Here the scatter gather list
  45 * elements are each tagged with the appropriate dma address
  46 * and length.  They are obtained via sg_dma_{address,length}(SG).
  47 *
  48 * NOTE: An implementation may be able to use a smaller number of
  49 *       DMA address/length pairs than there are SG table elements.
  50 *       (for example via virtual mapping capabilities)
  51 *       The routine returns the number of addr/length pairs actually
  52 *       used, at most nents.
  53 *
  54 * Device ownership issues as mentioned above for pci_map_single are
  55 * the same here.
  56 */
  57extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
  58                      enum dma_data_direction direction);
  59
  60/*
  61 * Unmap a set of streaming mode DMA translations.
  62 * Again, cpu read rules concerning calls here are the same as for
  63 * pci_unmap_single() above.
  64 */
  65extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
  66                      int nhwentries, enum dma_data_direction direction);
  67
  68#endif                          /* _BLACKFIN_DMA_MAPPING_H */
  69