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 161