LXR linux/include/linux/dma-mapping.h

   1#ifndef _LINUX_DMA_MAPPING_H
   2#define _LINUX_DMA_MAPPING_H
   3
   4#include <linux/device.h>
   5#include <linux/err.h>
   6
   7/* These definitions mirror those in pci.h, so they can be used
   8 * interchangeably with their PCI_ counterparts */
   9enum dma_data_direction {
  10        DMA_BIDIRECTIONAL = 0,
  11        DMA_TO_DEVICE = 1,
  12        DMA_FROM_DEVICE = 2,
  13        DMA_NONE = 3,
  14};
  15
  16#define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
  17
  18/*
  19 * NOTE: do not use the below macros in new code and do not add new definitions
  20 * here.
  21 *
  22 * Instead, just open-code DMA_BIT_MASK(n) within your driver
  23 */
  24#define DMA_64BIT_MASK  DMA_BIT_MASK(64)
  25#define DMA_48BIT_MASK  DMA_BIT_MASK(48)
  26#define DMA_47BIT_MASK  DMA_BIT_MASK(47)
  27#define DMA_40BIT_MASK  DMA_BIT_MASK(40)
  28#define DMA_39BIT_MASK  DMA_BIT_MASK(39)
  29#define DMA_35BIT_MASK  DMA_BIT_MASK(35)
  30#define DMA_32BIT_MASK  DMA_BIT_MASK(32)
  31#define DMA_31BIT_MASK  DMA_BIT_MASK(31)
  32#define DMA_30BIT_MASK  DMA_BIT_MASK(30)
  33#define DMA_29BIT_MASK  DMA_BIT_MASK(29)
  34#define DMA_28BIT_MASK  DMA_BIT_MASK(28)
  35#define DMA_24BIT_MASK  DMA_BIT_MASK(24)
  36
  37#define DMA_MASK_NONE   0x0ULL
  38
  39static inline int valid_dma_direction(int dma_direction)
  40{
  41        return ((dma_direction == DMA_BIDIRECTIONAL) ||
  42                (dma_direction == DMA_TO_DEVICE) ||
  43                (dma_direction == DMA_FROM_DEVICE));
  44}
  45
  46static inline int is_device_dma_capable(struct device *dev)
  47{
  48        return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
  49}
  50
  51#ifdef CONFIG_HAS_DMA
  52#include <asm/dma-mapping.h>
  53#else
  54#include <asm-generic/dma-mapping-broken.h>
  55#endif
  56
  57/* Backwards compat, remove in 2.7.x */
  58#define dma_sync_single         dma_sync_single_for_cpu
  59#define dma_sync_sg             dma_sync_sg_for_cpu
  60
  61extern u64 dma_get_required_mask(struct device *dev);
  62
  63static inline unsigned int dma_get_max_seg_size(struct device *dev)
  64{
  65        return dev->dma_parms ? dev->dma_parms->max_segment_size : 65536;
  66}
  67
  68static inline unsigned int dma_set_max_seg_size(struct device *dev,
  69                                                unsigned int size)
  70{
  71        if (dev->dma_parms) {
  72                dev->dma_parms->max_segment_size = size;
  73                return 0;
  74        } else
  75                return -EIO;
  76}
  77
  78static inline unsigned long dma_get_seg_boundary(struct device *dev)
  79{
  80        return dev->dma_parms ?
  81                dev->dma_parms->segment_boundary_mask : 0xffffffff;
  82}
  83
  84static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
  85{
  86        if (dev->dma_parms) {
  87                dev->dma_parms->segment_boundary_mask = mask;
  88                return 0;
  89        } else
  90                return -EIO;
  91}
  92
  93/* flags for the coherent memory api */
  94#define DMA_MEMORY_MAP                  0x01
  95#define DMA_MEMORY_IO                   0x02
  96#define DMA_MEMORY_INCLUDES_CHILDREN    0x04
  97#define DMA_MEMORY_EXCLUSIVE            0x08
  98
  99#ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 100static inline int
 101dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 102                            dma_addr_t device_addr, size_t size, int flags)
 103{
 104        return 0;
 105}
 106
 107static inline void
 108dma_release_declared_memory(struct device *dev)
 109{
 110}
 111
 112static inline void *
 113dma_mark_declared_memory_occupied(struct device *dev,
 114                                  dma_addr_t device_addr, size_t size)
 115{
 116        return ERR_PTR(-EBUSY);
 117}
 118#endif
 119
 120/*
 121 * Managed DMA API
 122 */
 123extern void *dmam_alloc_coherent(struct device *dev, size_t size,
 124                                 dma_addr_t *dma_handle, gfp_t gfp);
 125extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 126                               dma_addr_t dma_handle);
 127extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
 128                                    dma_addr_t *dma_handle, gfp_t gfp);
 129extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 130                                  dma_addr_t dma_handle);
 131#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 132extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 133                                        dma_addr_t device_addr, size_t size,
 134                                        int flags);
 135extern void dmam_release_declared_memory(struct device *dev);
 136#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 137static inline int dmam_declare_coherent_memory(struct device *dev,
 138                                dma_addr_t bus_addr, dma_addr_t device_addr,
 139                                size_t size, gfp_t gfp)
 140{
 141        return 0;
 142}
 143
 144static inline void dmam_release_declared_memory(struct device *dev)
 145{
 146}
 147#endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 148
 149#ifndef CONFIG_HAVE_DMA_ATTRS
 150struct dma_attrs;
 151
 152#define dma_map_single_attrs(dev, cpu_addr, size, dir, attrs) \
 153        dma_map_single(dev, cpu_addr, size, dir)
 154
 155#define dma_unmap_single_attrs(dev, dma_addr, size, dir, attrs) \
 156        dma_unmap_single(dev, dma_addr, size, dir)
 157
 158#define dma_map_sg_attrs(dev, sgl, nents, dir, attrs) \
 159        dma_map_sg(dev, sgl, nents, dir)
 160
 161#define dma_unmap_sg_attrs(dev, sgl, nents, dir, attrs) \
 162        dma_unmap_sg(dev, sgl, nents, dir)
 163
 164#endif /* CONFIG_HAVE_DMA_ATTRS */
 165
 166#endif
 167