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
dma_direct_sync_sg_for_device(struct device * dev,struct scatterlist * sgl,int nents,enum dma_data_direction dir)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
dma_direct_unmap_sg(struct device * dev,struct scatterlist * sgl,int nents,enum dma_data_direction dir,unsigned long attrs)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 }
dma_direct_sync_sg_for_cpu(struct device * dev,struct scatterlist * sgl,int nents,enum dma_data_direction dir)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
dma_direct_sync_single_for_device(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir)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
dma_direct_sync_single_for_cpu(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir,bool flush)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
dma_direct_unmap_phys(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir,unsigned long attrs,bool flush)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