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/PCI/PCI-DMA-mapping.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
  17 extern dma_addr_t bad_dma_address;
  18 extern int iommu_merge;
  19 extern struct device x86_dma_fallback_dev;
  20 extern int panic_on_overflow;
  21
  22 extern struct dma_map_ops *dma_ops;
  23
  24 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  25 {
  26 #ifdef CONFIG_X86_32
  27         return dma_ops;
  28 #else
  29         if (unlikely(!dev) || !dev->archdata.dma_ops)
  30                 return dma_ops;
  31         else
  32                 return dev->archdata.dma_ops;
  33 #endif
  34 }
  35
  36 #include <asm-generic/dma-mapping-common.h>
  37
  38 /* Make sure we keep the same behaviour */
  39 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
  40 {
  41         struct dma_map_ops *ops = get_dma_ops(dev);
  42         if (ops->mapping_error)
  43                 return ops->mapping_error(dev, dma_addr);
  44
  45         return (dma_addr == bad_dma_address);
  46 }
  47
  48 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
  49 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
  50 #define dma_is_consistent(d, h) (1)
  51
  52 extern int dma_supported(struct device *hwdev, u64 mask);
  53 extern int dma_set_mask(struct device *dev, u64 mask);
  54
  55 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
  56                                         dma_addr_t *dma_addr, gfp_t flag);
  57
  58 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  59 {
  60         if (!dev->dma_mask)
  61                 return 0;
  62
  63         return addr + size <= *dev->dma_mask;
  64 }
  65
  66 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  67 {
  68         return paddr;
  69 }
  70
  71 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  72 {
  73         return daddr;
  74 }
  75
  76 static inline void
  77 dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  78         enum dma_data_direction dir)
  79 {
  80         flush_write_buffers();
  81 }
  82
  83 static inline int dma_get_cache_alignment(void)
  84 {
  85         /* no easy way to get cache size on all x86, so return the
  86          * maximum possible, to be safe */
  87         return boot_cpu_data.x86_clflush_size;
  88 }
  89
  90 static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
  91                                                     gfp_t gfp)
  92 {
  93         unsigned long dma_mask = 0;
  94
  95         dma_mask = dev->coherent_dma_mask;
  96         if (!dma_mask)
  97                 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
  98
  99         return dma_mask;
 100 }
 101
 102 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 103 {
 104         unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
 105
 106         if (dma_mask <= DMA_BIT_MASK(24))
 107                 gfp |= GFP_DMA;
 108 #ifdef CONFIG_X86_64
 109         if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
 110                 gfp |= GFP_DMA32;
 111 #endif
 112        return gfp;
 113 }
 114
 115 static inline void *
 116 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
 117                 gfp_t gfp)
 118 {
 119         struct dma_map_ops *ops = get_dma_ops(dev);
 120         void *memory;
 121
 122         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 123
 124         if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
 125                 return memory;
 126
 127         if (!dev) {
 128                 dev = &x86_dma_fallback_dev;
 129                 gfp |= GFP_DMA;
 130         }
 131
 132         if (!is_device_dma_capable(dev))
 133                 return NULL;
 134
 135         if (!ops->alloc_coherent)
 136                 return NULL;
 137
 138         memory = ops->alloc_coherent(dev, size, dma_handle,
 139                                      dma_alloc_coherent_gfp_flags(dev, gfp));
 140         debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
 141
 142         return memory;
 143 }
 144
 145 static inline void dma_free_coherent(struct device *dev, size_t size,
 146                                      void *vaddr, dma_addr_t bus)
 147 {
 148         struct dma_map_ops *ops = get_dma_ops(dev);
 149
 150         WARN_ON(irqs_disabled());       /* for portability */
 151
 152         if (dma_release_from_coherent(dev, get_order(size), vaddr))
 153                 return;
 154
 155         debug_dma_free_coherent(dev, size, vaddr, bus);
 156         if (ops->free_coherent)
 157                 ops->free_coherent(dev, size, vaddr, bus);
 158 }
 159
 160 #endif