arch/x86/include/asm/dma-mapping.h

   1 #ifndef _ASM_X86_DMA_MAPPING_H
   2 #define _ASM_X86_DMA_MAPPING_H
   3
   4 /*
   5  * IOMMU interface. See Documentation/DMA-API-HOWTO.txt and
   6  * Documentation/DMA-API.txt for documentation.
   7  */
   8
   9 #include <linux/kmemcheck.h>
  10 #include <linux/scatterlist.h>
  11 #include <linux/dma-debug.h>
  12 #include <linux/dma-attrs.h>
  13 #include <asm/io.h>
  14 #include <asm/swiotlb.h>
  15 #include <asm-generic/dma-coherent.h>
  16 #include <linux/dma-contiguous.h>
  17
  18 #ifdef CONFIG_ISA
  19 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
  20 #else
  21 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
  22 #endif
  23
  24 #define DMA_ERROR_CODE  0
  25
  26 extern int iommu_merge;
  27 extern struct device x86_dma_fallback_dev;
  28 extern int panic_on_overflow;
  29
  30 extern struct dma_map_ops *dma_ops;
  31
  32 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  33 {
  34 #ifndef CONFIG_X86_DEV_DMA_OPS
  35         return dma_ops;
  36 #else
  37         if (unlikely(!dev) || !dev->archdata.dma_ops)
  38                 return dma_ops;
  39         else
  40                 return dev->archdata.dma_ops;
  41 #endif
  42 }
  43
  44 #include <asm-generic/dma-mapping-common.h>
  45
  46 /* Make sure we keep the same behaviour */
  47 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  48 {
  49         struct dma_map_ops *ops = get_dma_ops(dev);
  50         debug_dma_mapping_error(dev, dma_addr);
  51         if (ops->mapping_error)
  52                 return ops->mapping_error(dev, dma_addr);
  53
  54         return (dma_addr == DMA_ERROR_CODE);
  55 }
  56
  57 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
  58 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
  59
  60 extern int dma_supported(struct device *hwdev, u64 mask);
  61 extern int dma_set_mask(struct device *dev, u64 mask);
  62
  63 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
  64                                         dma_addr_t *dma_addr, gfp_t flag,
  65                                         struct dma_attrs *attrs);
  66
  67 extern void dma_generic_free_coherent(struct device *dev, size_t size,
  68                                       void *vaddr, dma_addr_t dma_addr,
  69                                       struct dma_attrs *attrs);
  70
  71 #ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
  72 extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
  73 extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
  74 extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
  75 #else
  76
  77 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  78 {
  79         if (!dev->dma_mask)
  80                 return 0;
  81
  82         return addr + size - 1 <= *dev->dma_mask;
  83 }
  84
  85 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  86 {
  87         return paddr;
  88 }
  89
  90 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  91 {
  92         return daddr;
  93 }
  94 #endif /* CONFIG_X86_DMA_REMAP */
  95
  96 static inline void
  97 dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  98         enum dma_data_direction dir)
  99 {
 100         flush_write_buffers();
 101 }
 102
 103 static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
 104                                                     gfp_t gfp)
 105 {
 106         unsigned long dma_mask = 0;
 107
 108         dma_mask = dev->coherent_dma_mask;
 109         if (!dma_mask)
 110                 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
 111
 112         return dma_mask;
 113 }
 114
 115 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 116 {
 117         unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
 118
 119         if (dma_mask <= DMA_BIT_MASK(24))
 120                 gfp |= GFP_DMA;
 121 #ifdef CONFIG_X86_64
 122         if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
 123                 gfp |= GFP_DMA32;
 124 #endif
 125        return gfp;
 126 }
 127
 128 #define dma_alloc_coherent(d,s,h,f)     dma_alloc_attrs(d,s,h,f,NULL)
 129
 130 static inline void *
 131 dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 132                 gfp_t gfp, struct dma_attrs *attrs)
 133 {
 134         struct dma_map_ops *ops = get_dma_ops(dev);
 135         void *memory;
 136
 137         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 138
 139         if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
 140                 return memory;
 141
 142         if (!dev)
 143                 dev = &x86_dma_fallback_dev;
 144
 145         if (!is_device_dma_capable(dev))
 146                 return NULL;
 147
 148         if (!ops->alloc)
 149                 return NULL;
 150
 151         memory = ops->alloc(dev, size, dma_handle,
 152                             dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
 153         debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
 154
 155         return memory;
 156 }
 157
 158 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 159
 160 static inline void dma_free_attrs(struct device *dev, size_t size,
 161                                   void *vaddr, dma_addr_t bus,
 162                                   struct dma_attrs *attrs)
 163 {
 164         struct dma_map_ops *ops = get_dma_ops(dev);
 165
 166         WARN_ON(irqs_disabled());       /* for portability */
 167
 168         if (dma_release_from_coherent(dev, get_order(size), vaddr))
 169                 return;
 170
 171         debug_dma_free_coherent(dev, size, vaddr, bus);
 172         if (ops->free)
 173                 ops->free(dev, size, vaddr, bus, attrs);
 174 }
 175
 176 #endif