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 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 #include <asm-generic/dma-mapping-common.h> 44 45 /* Make sure we keep the same behaviour */ 46 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) 47 { 48 struct dma_map_ops *ops = get_dma_ops(dev); 49 if (ops->mapping_error) 50 return ops->mapping_error(dev, dma_addr); 51 52 return (dma_addr == DMA_ERROR_CODE); 53 } 54 55 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f) 56 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h) 57 58 extern int dma_supported(struct device *hwdev, u64 mask); 59 extern int dma_set_mask(struct device *dev, u64 mask); 60 61 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size, 62 dma_addr_t *dma_addr, gfp_t flag, 63 struct dma_attrs *attrs); 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 83 static inline void 84 dma_cache_sync(struct device *dev, void *vaddr, size_t size, 85 enum dma_data_direction dir) 86 { 87 flush_write_buffers(); 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 #define dma_alloc_coherent(d,s,h,f) dma_alloc_attrs(d,s,h,f,NULL) 116 117 static inline void * 118 dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, 119 gfp_t gfp, struct dma_attrs *attrs) 120 { 121 struct dma_map_ops *ops = get_dma_ops(dev); 122 void *memory; 123 124 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32); 125 126 if (dma_alloc_from_coherent(dev, size, dma_handle, &memory)) 127 return memory; 128 129 if (!dev) 130 dev = &x86_dma_fallback_dev; 131 132 if (!is_device_dma_capable(dev)) 133 return NULL; 134 135 if (!ops->alloc) 136 return NULL; 137 138 memory = ops->alloc(dev, size, dma_handle, 139 dma_alloc_coherent_gfp_flags(dev, gfp), attrs); 140 debug_dma_alloc_coherent(dev, size, *dma_handle, memory); 141 142 return memory; 143 } 144 145 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL) 146 147 static inline void dma_free_attrs(struct device *dev, size_t size, 148 void *vaddr, dma_addr_t bus, 149 struct dma_attrs *attrs) 150 { 151 struct dma_map_ops *ops = get_dma_ops(dev); 152 153 WARN_ON(irqs_disabled()); /* for portability */ 154 155 if (dma_release_from_coherent(dev, get_order(size), vaddr)) 156 return; 157 158 debug_dma_free_coherent(dev, size, vaddr, bus); 159 if (ops->free) 160 ops->free(dev, size, vaddr, bus, attrs); 161 } 162 163 #endif 164