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 <asm/io.h> 13 #include <asm/swiotlb.h> 14 #include <linux/dma-contiguous.h> 15 16 #ifdef CONFIG_ISA 17 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(24) 18 #else 19 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(32) 20 #endif 21 22 #define DMA_ERROR_CODE 0 23 24 extern int iommu_merge; 25 extern struct device x86_dma_fallback_dev; 26 extern int panic_on_overflow; 27 28 extern const struct dma_map_ops *dma_ops; 29 30 static inline const struct dma_map_ops *get_dma_ops(struct device *dev) 31 { 32 #ifndef CONFIG_X86_DEV_DMA_OPS 33 return dma_ops; 34 #else 35 if (unlikely(!dev) || !dev->archdata.dma_ops) 36 return dma_ops; 37 else 38 return dev->archdata.dma_ops; 39 #endif 40 } 41 42 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp); 43 #define arch_dma_alloc_attrs arch_dma_alloc_attrs 44 45 #define HAVE_ARCH_DMA_SUPPORTED 1 46 extern int dma_supported(struct device *hwdev, u64 mask); 47 48 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size, 49 dma_addr_t *dma_addr, gfp_t flag, 50 unsigned long attrs); 51 52 extern void dma_generic_free_coherent(struct device *dev, size_t size, 53 void *vaddr, dma_addr_t dma_addr, 54 unsigned long attrs); 55 56 #ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */ 57 extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size); 58 extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr); 59 extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr); 60 #else 61 62 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) 63 { 64 if (!dev->dma_mask) 65 return 0; 66 67 return addr + size - 1 <= *dev->dma_mask; 68 } 69 70 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) 71 { 72 return paddr; 73 } 74 75 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) 76 { 77 return daddr; 78 } 79 #endif /* CONFIG_X86_DMA_REMAP */ 80 81 static inline void 82 dma_cache_sync(struct device *dev, void *vaddr, size_t size, 83 enum dma_data_direction dir) 84 { 85 flush_write_buffers(); 86 } 87 88 static inline unsigned long dma_alloc_coherent_mask(struct device *dev, 89 gfp_t gfp) 90 { 91 unsigned long dma_mask = 0; 92 93 dma_mask = dev->coherent_dma_mask; 94 if (!dma_mask) 95 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32); 96 97 return dma_mask; 98 } 99 100 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp) 101 { 102 unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp); 103 104 if (dma_mask <= DMA_BIT_MASK(24)) 105 gfp |= GFP_DMA; 106 #ifdef CONFIG_X86_64 107 if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) 108 gfp |= GFP_DMA32; 109 #endif 110 return gfp; 111 } 112 113 #endif 114