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