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 <linux/dma-contiguous.h>
  16
  17 #ifdef CONFIG_ISA
  18 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
  19 #else
  20 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
  21 #endif
  22
  23 #define DMA_ERROR_CODE  0
  24
  25 extern int iommu_merge;
  26 extern struct device x86_dma_fallback_dev;
  27 extern int panic_on_overflow;
  28
  29 extern struct dma_map_ops *dma_ops;
  30
  31 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  32 {
  33 #ifndef CONFIG_X86_DEV_DMA_OPS
  34         return dma_ops;
  35 #else
  36         if (unlikely(!dev) || !dev->archdata.dma_ops)
  37                 return dma_ops;
  38         else
  39                 return dev->archdata.dma_ops;
  40 #endif
  41 }
  42
  43 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
  44 #define arch_dma_alloc_attrs arch_dma_alloc_attrs
  45
  46 #define HAVE_ARCH_DMA_SUPPORTED 1
  47 extern int dma_supported(struct device *hwdev, u64 mask);
  48
  49 #include <asm-generic/dma-mapping-common.h>
  50
  51 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
  52                                         dma_addr_t *dma_addr, gfp_t flag,
  53                                         struct dma_attrs *attrs);
  54
  55 extern void dma_generic_free_coherent(struct device *dev, size_t size,
  56                                       void *vaddr, dma_addr_t dma_addr,
  57                                       struct dma_attrs *attrs);
  58
  59 #ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
  60 extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
  61 extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
  62 extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
  63 #else
  64
  65 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  66 {
  67         if (!dev->dma_mask)
  68                 return 0;
  69
  70         return addr + size - 1 <= *dev->dma_mask;
  71 }
  72
  73 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  74 {
  75         return paddr;
  76 }
  77
  78 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  79 {
  80         return daddr;
  81 }
  82 #endif /* CONFIG_X86_DMA_REMAP */
  83
  84 static inline void
  85 dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  86         enum dma_data_direction dir)
  87 {
  88         flush_write_buffers();
  89 }
  90
  91 static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
  92                                                     gfp_t gfp)
  93 {
  94         unsigned long dma_mask = 0;
  95
  96         dma_mask = dev->coherent_dma_mask;
  97         if (!dma_mask)
  98                 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
  99
 100         return dma_mask;
 101 }
 102
 103 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 104 {
 105         unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
 106
 107         if (dma_mask <= DMA_BIT_MASK(24))
 108                 gfp |= GFP_DMA;
 109 #ifdef CONFIG_X86_64
 110         if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
 111                 gfp |= GFP_DMA32;
 112 #endif
 113        return gfp;
 114 }
 115
 116 #endif