1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2018 Christoph Hellwig. 4 * 5 * DMA operations that map physical memory directly without using an IOMMU. 6 */ 7 #ifndef _KERNEL_DMA_DIRECT_H 8 #define _KERNEL_DMA_DIRECT_H 9 10 #include <linux/dma-direct.h> 11 #include <linux/memremap.h> 12 13 int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt, 14 void *cpu_addr, dma_addr_t dma_addr, size_t size, 15 unsigned long attrs); 16 bool dma_direct_can_mmap(struct device *dev); 17 int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, 18 void *cpu_addr, dma_addr_t dma_addr, size_t size, 19 unsigned long attrs); 20 dma_addr_t dma_direct_map_phys(struct device *dev, phys_addr_t phys, 21 size_t size, enum dma_data_direction dir, 22 unsigned long attrs, bool flush); 23 bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr); 24 int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, 25 enum dma_data_direction dir, unsigned long attrs); 26 bool dma_direct_all_ram_mapped(struct device *dev); 27 size_t dma_direct_max_mapping_size(struct device *dev); 28 29 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ 30 defined(CONFIG_SWIOTLB) 31 void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, 32 int nents, enum dma_data_direction dir); 33 #else 34 static inline void dma_direct_sync_sg_for_device(struct device *dev, 35 struct scatterlist *sgl, int nents, enum dma_data_direction dir) 36 { 37 } 38 #endif 39 40 #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ 41 defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \ 42 defined(CONFIG_SWIOTLB) 43 void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, 44 int nents, enum dma_data_direction dir, unsigned long attrs); 45 void dma_direct_sync_sg_for_cpu(struct device *dev, 46 struct scatterlist *sgl, int nents, enum dma_data_direction dir); 47 #else 48 static inline void dma_direct_unmap_sg(struct device *dev, 49 struct scatterlist *sgl, int nents, enum dma_data_direction dir, 50 unsigned long attrs) 51 { 52 } 53 static inline void dma_direct_sync_sg_for_cpu(struct device *dev, 54 struct scatterlist *sgl, int nents, enum dma_data_direction dir) 55 { 56 } 57 #endif 58 59 static inline void dma_direct_sync_single_for_device(struct device *dev, 60 dma_addr_t addr, size_t size, enum dma_data_direction dir) 61 { 62 phys_addr_t paddr = dma_to_phys(dev, addr); 63 64 swiotlb_sync_single_for_device(dev, paddr, size, dir); 65 66 if (!dev_is_dma_coherent(dev)) { 67 arch_sync_dma_for_device(paddr, size, dir); 68 arch_sync_dma_flush(); 69 } 70 } 71 72 static inline void dma_direct_sync_single_for_cpu(struct device *dev, 73 dma_addr_t addr, size_t size, enum dma_data_direction dir, 74 bool flush) 75 { 76 phys_addr_t paddr = dma_to_phys(dev, addr); 77 78 if (!dev_is_dma_coherent(dev)) { 79 arch_sync_dma_for_cpu(paddr, size, dir); 80 if (flush) 81 arch_sync_dma_flush(); 82 arch_sync_dma_for_cpu_all(); 83 } 84 85 swiotlb_sync_single_for_cpu(dev, paddr, size, dir); 86 } 87 88 static inline void dma_direct_unmap_phys(struct device *dev, dma_addr_t addr, 89 size_t size, enum dma_data_direction dir, unsigned long attrs, 90 bool flush) 91 { 92 phys_addr_t phys; 93 94 if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) 95 /* nothing to do: uncached and no swiotlb */ 96 return; 97 98 phys = dma_to_phys(dev, addr); 99 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 100 dma_direct_sync_single_for_cpu(dev, addr, size, dir, flush); 101 102 swiotlb_tbl_unmap_single(dev, phys, size, dir, 103 attrs | DMA_ATTR_SKIP_CPU_SYNC); 104 } 105 #endif /* _KERNEL_DMA_DIRECT_H */ 106