1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_DMA_MAPPING_H 3 #define _ASM_X86_DMA_MAPPING_H 4 5 /* 6 * IOMMU interface. See Documentation/DMA-API-HOWTO.txt and 7 * Documentation/DMA-API.txt for documentation. 8 */ 9 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 #include <linux/mem_encrypt.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 extern int iommu_merge; 24 extern struct device x86_dma_fallback_dev; 25 extern int panic_on_overflow; 26 27 extern const struct dma_map_ops *dma_ops; 28 29 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus) 30 { 31 return dma_ops; 32 } 33 34 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp); 35 #define arch_dma_alloc_attrs arch_dma_alloc_attrs 36 37 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size, 38 dma_addr_t *dma_addr, gfp_t flag, 39 unsigned long attrs); 40 41 extern void dma_generic_free_coherent(struct device *dev, size_t size, 42 void *vaddr, dma_addr_t dma_addr, 43 unsigned long attrs); 44 45 #ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */ 46 extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size); 47 extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr); 48 extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr); 49 #else 50 51 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) 52 { 53 if (!dev->dma_mask) 54 return 0; 55 56 return addr + size - 1 <= *dev->dma_mask; 57 } 58 59 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) 60 { 61 return __sme_set(paddr); 62 } 63 64 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) 65 { 66 return __sme_clr(daddr); 67 } 68 #endif /* CONFIG_X86_DMA_REMAP */ 69 70 static inline unsigned long dma_alloc_coherent_mask(struct device *dev, 71 gfp_t gfp) 72 { 73 unsigned long dma_mask = 0; 74 75 dma_mask = dev->coherent_dma_mask; 76 if (!dma_mask) 77 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32); 78 79 return dma_mask; 80 } 81 82 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp) 83 { 84 unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp); 85 86 if (dma_mask <= DMA_BIT_MASK(24)) 87 gfp |= GFP_DMA; 88 #ifdef CONFIG_X86_64 89 if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) 90 gfp |= GFP_DMA32; 91 #endif 92 return gfp; 93 } 94 95 #endif 96