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 */
   9 enum 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
  39 static 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
  46 static 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 static inline int is_buffer_dma_capable(u64 mask, dma_addr_t addr, size_t size)
  52 {
  53         return addr + size <= mask;
  54 }
  55
  56 #ifdef CONFIG_HAS_DMA
  57 #include <asm/dma-mapping.h>
  58 #else
  59 #include <asm-generic/dma-mapping-broken.h>
  60 #endif
  61
  62 /* Backwards compat, remove in 2.7.x */
  63 #define dma_sync_single         dma_sync_single_for_cpu
  64 #define dma_sync_sg             dma_sync_sg_for_cpu
  65
  66 static inline u64 dma_get_mask(struct device *dev)
  67 {
  68         if (dev && dev->dma_mask && *dev->dma_mask)
  69                 return *dev->dma_mask;
  70         return DMA_32BIT_MASK;
  71 }
  72
  73 extern u64 dma_get_required_mask(struct device *dev);
  74
  75 static inline unsigned int dma_get_max_seg_size(struct device *dev)
  76 {
  77         return dev->dma_parms ? dev->dma_parms->max_segment_size : 65536;
  78 }
  79
  80 static inline unsigned int dma_set_max_seg_size(struct device *dev,
  81                                                 unsigned int size)
  82 {
  83         if (dev->dma_parms) {
  84                 dev->dma_parms->max_segment_size = size;
  85                 return 0;
  86         } else
  87                 return -EIO;
  88 }
  89
  90 static inline unsigned long dma_get_seg_boundary(struct device *dev)
  91 {
  92         return dev->dma_parms ?
  93                 dev->dma_parms->segment_boundary_mask : 0xffffffff;
  94 }
  95
  96 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
  97 {
  98         if (dev->dma_parms) {
  99                 dev->dma_parms->segment_boundary_mask = mask;
 100                 return 0;
 101         } else
 102                 return -EIO;
 103 }
 104
 105 /* flags for the coherent memory api */
 106 #define DMA_MEMORY_MAP                  0x01
 107 #define DMA_MEMORY_IO                   0x02
 108 #define DMA_MEMORY_INCLUDES_CHILDREN    0x04
 109 #define DMA_MEMORY_EXCLUSIVE            0x08
 110
 111 #ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 112 static inline int
 113 dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 114                             dma_addr_t device_addr, size_t size, int flags)
 115 {
 116         return 0;
 117 }
 118
 119 static inline void
 120 dma_release_declared_memory(struct device *dev)
 121 {
 122 }
 123
 124 static inline void *
 125 dma_mark_declared_memory_occupied(struct device *dev,
 126                                   dma_addr_t device_addr, size_t size)
 127 {
 128         return ERR_PTR(-EBUSY);
 129 }
 130 #endif
 131
 132 /*
 133  * Managed DMA API
 134  */
 135 extern void *dmam_alloc_coherent(struct device *dev, size_t size,
 136                                  dma_addr_t *dma_handle, gfp_t gfp);
 137 extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 138                                dma_addr_t dma_handle);
 139 extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
 140                                     dma_addr_t *dma_handle, gfp_t gfp);
 141 extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 142                                   dma_addr_t dma_handle);
 143 #ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 144 extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
 145                                         dma_addr_t device_addr, size_t size,
 146                                         int flags);
 147 extern void dmam_release_declared_memory(struct device *dev);
 148 #else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 149 static inline int dmam_declare_coherent_memory(struct device *dev,
 150                                 dma_addr_t bus_addr, dma_addr_t device_addr,
 151                                 size_t size, gfp_t gfp)
 152 {
 153         return 0;
 154 }
 155
 156 static inline void dmam_release_declared_memory(struct device *dev)
 157 {
 158 }
 159 #endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 160
 161 #ifndef CONFIG_HAVE_DMA_ATTRS
 162 struct dma_attrs;
 163
 164 #define dma_map_single_attrs(dev, cpu_addr, size, dir, attrs) \
 165         dma_map_single(dev, cpu_addr, size, dir)
 166
 167 #define dma_unmap_single_attrs(dev, dma_addr, size, dir, attrs) \
 168         dma_unmap_single(dev, dma_addr, size, dir)
 169
 170 #define dma_map_sg_attrs(dev, sgl, nents, dir, attrs) \
 171         dma_map_sg(dev, sgl, nents, dir)
 172
 173 #define dma_unmap_sg_attrs(dev, sgl, nents, dir, attrs) \
 174         dma_unmap_sg(dev, sgl, nents, dir)
 175
 176 #endif /* CONFIG_HAVE_DMA_ATTRS */
 177
 178 #endif