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 177