xref: /linux-6.15/include/linux/dma-mapping.h (revision aeb3f462)
1 #ifndef _ASM_LINUX_DMA_MAPPING_H
2 #define _ASM_LINUX_DMA_MAPPING_H
3 
4 #include <linux/device.h>
5 #include <linux/err.h>
6 
7 /* These definitions mirror those in pci.h, so they can be used
8  * interchangeably with their PCI_ counterparts */
9 enum dma_data_direction {
10 	DMA_BIDIRECTIONAL = 0,
11 	DMA_TO_DEVICE = 1,
12 	DMA_FROM_DEVICE = 2,
13 	DMA_NONE = 3,
14 };
15 
16 #define DMA_64BIT_MASK	0xffffffffffffffffULL
17 #define DMA_48BIT_MASK	0x0000ffffffffffffULL
18 #define DMA_40BIT_MASK	0x000000ffffffffffULL
19 #define DMA_39BIT_MASK	0x0000007fffffffffULL
20 #define DMA_32BIT_MASK	0x00000000ffffffffULL
21 #define DMA_31BIT_MASK	0x000000007fffffffULL
22 #define DMA_30BIT_MASK	0x000000003fffffffULL
23 #define DMA_29BIT_MASK	0x000000001fffffffULL
24 #define DMA_28BIT_MASK	0x000000000fffffffULL
25 #define DMA_24BIT_MASK	0x0000000000ffffffULL
26 
27 static inline int valid_dma_direction(int dma_direction)
28 {
29 	return ((dma_direction == DMA_BIDIRECTIONAL) ||
30 		(dma_direction == DMA_TO_DEVICE) ||
31 		(dma_direction == DMA_FROM_DEVICE));
32 }
33 
34 #ifdef CONFIG_HAS_DMA
35 #include <asm/dma-mapping.h>
36 #else
37 #include <asm-generic/dma-mapping-broken.h>
38 #endif
39 
40 /* Backwards compat, remove in 2.7.x */
41 #define dma_sync_single		dma_sync_single_for_cpu
42 #define dma_sync_sg		dma_sync_sg_for_cpu
43 
44 extern u64 dma_get_required_mask(struct device *dev);
45 
46 /* flags for the coherent memory api */
47 #define	DMA_MEMORY_MAP			0x01
48 #define DMA_MEMORY_IO			0x02
49 #define DMA_MEMORY_INCLUDES_CHILDREN	0x04
50 #define DMA_MEMORY_EXCLUSIVE		0x08
51 
52 #ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
53 static inline int
54 dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
55 			    dma_addr_t device_addr, size_t size, int flags)
56 {
57 	return 0;
58 }
59 
60 static inline void
61 dma_release_declared_memory(struct device *dev)
62 {
63 }
64 
65 static inline void *
66 dma_mark_declared_memory_occupied(struct device *dev,
67 				  dma_addr_t device_addr, size_t size)
68 {
69 	return ERR_PTR(-EBUSY);
70 }
71 #endif
72 
73 /*
74  * Managed DMA API
75  */
76 extern void *dmam_alloc_coherent(struct device *dev, size_t size,
77 				 dma_addr_t *dma_handle, gfp_t gfp);
78 extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
79 			       dma_addr_t dma_handle);
80 extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
81 				    dma_addr_t *dma_handle, gfp_t gfp);
82 extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
83 				  dma_addr_t dma_handle);
84 #ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
85 extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
86 					dma_addr_t device_addr, size_t size,
87 					int flags);
88 extern void dmam_release_declared_memory(struct device *dev);
89 #else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
90 static inline int dmam_declare_coherent_memory(struct device *dev,
91 				dma_addr_t bus_addr, dma_addr_t device_addr,
92 				size_t size, gfp_t gfp)
93 {
94 	return 0;
95 }
96 
97 static inline void dmam_release_declared_memory(struct device *dev)
98 {
99 }
100 #endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
101 
102 #endif
103