OpenCloudOS-Kernel/include/asm-blackfin/dma-mapping.h

67 lines
2.5 KiB
C

#ifndef _BLACKFIN_DMA_MAPPING_H
#define _BLACKFIN_DMA_MAPPING_H
#include <asm/scatterlist.h>
void dma_alloc_init(unsigned long start, unsigned long end);
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp);
void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle);
/*
* Now for the API extensions over the pci_ one
*/
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
/*
* Map a single buffer of the indicated size for DMA in streaming mode.
* The 32-bit bus address to use is returned.
*
* Once the device is given the dma address, the device owns this memory
* until either pci_unmap_single or pci_dma_sync_single is performed.
*/
extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction);
/*
* Unmap a single streaming mode DMA translation. The dma_addr and size
* must match what was provided for in a previous pci_map_single call. All
* other usages are undefined.
*
* After this call, reads by the cpu to the buffer are guarenteed to see
* whatever the device wrote there.
*/
extern void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction direction);
/*
* Map a set of buffers described by scatterlist in streaming
* mode for DMA. This is the scather-gather version of the
* above pci_map_single interface. Here the scatter gather list
* elements are each tagged with the appropriate dma address
* and length. They are obtained via sg_dma_{address,length}(SG).
*
* NOTE: An implementation may be able to use a smaller number of
* DMA address/length pairs than there are SG table elements.
* (for example via virtual mapping capabilities)
* The routine returns the number of addr/length pairs actually
* used, at most nents.
*
* Device ownership issues as mentioned above for pci_map_single are
* the same here.
*/
extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction direction);
/*
* Unmap a set of streaming mode DMA translations.
* Again, cpu read rules concerning calls here are the same as for
* pci_unmap_single() above.
*/
extern void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
int nhwentries, enum dma_data_direction direction);
#endif /* _BLACKFIN_DMA_MAPPING_H */