Linux kernel mirror (for testing)
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linux
1#ifndef _LINUX_DMA_MAPPING_H
2#define _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 */
9enum 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_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
17
18/*
19 * NOTE: do not use the below macros in new code and do not add new definitions
20 * here.
21 *
22 * Instead, just open-code DMA_BIT_MASK(n) within your driver
23 */
24#define DMA_64BIT_MASK DMA_BIT_MASK(64)
25#define DMA_48BIT_MASK DMA_BIT_MASK(48)
26#define DMA_47BIT_MASK DMA_BIT_MASK(47)
27#define DMA_40BIT_MASK DMA_BIT_MASK(40)
28#define DMA_39BIT_MASK DMA_BIT_MASK(39)
29#define DMA_35BIT_MASK DMA_BIT_MASK(35)
30#define DMA_32BIT_MASK DMA_BIT_MASK(32)
31#define DMA_31BIT_MASK DMA_BIT_MASK(31)
32#define DMA_30BIT_MASK DMA_BIT_MASK(30)
33#define DMA_29BIT_MASK DMA_BIT_MASK(29)
34#define DMA_28BIT_MASK DMA_BIT_MASK(28)
35#define DMA_24BIT_MASK DMA_BIT_MASK(24)
36
37#define DMA_MASK_NONE 0x0ULL
38
39static inline int valid_dma_direction(int dma_direction)
40{
41 return ((dma_direction == DMA_BIDIRECTIONAL) ||
42 (dma_direction == DMA_TO_DEVICE) ||
43 (dma_direction == DMA_FROM_DEVICE));
44}
45
46static inline int is_device_dma_capable(struct device *dev)
47{
48 return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
49}
50
51static inline int is_buffer_dma_capable(u64 mask, dma_addr_t addr, size_t size)
52{
53 return addr + size <= mask;
54}
55
56#ifdef CONFIG_HAS_DMA
57#include <asm/dma-mapping.h>
58#else
59#include <asm-generic/dma-mapping-broken.h>
60#endif
61
62/* Backwards compat, remove in 2.7.x */
63#define dma_sync_single dma_sync_single_for_cpu
64#define dma_sync_sg dma_sync_sg_for_cpu
65
66static inline u64 dma_get_mask(struct device *dev)
67{
68 if (dev && dev->dma_mask && *dev->dma_mask)
69 return *dev->dma_mask;
70 return DMA_32BIT_MASK;
71}
72
73extern u64 dma_get_required_mask(struct device *dev);
74
75static inline unsigned int dma_get_max_seg_size(struct device *dev)
76{
77 return dev->dma_parms ? dev->dma_parms->max_segment_size : 65536;
78}
79
80static inline unsigned int dma_set_max_seg_size(struct device *dev,
81 unsigned int size)
82{
83 if (dev->dma_parms) {
84 dev->dma_parms->max_segment_size = size;
85 return 0;
86 } else
87 return -EIO;
88}
89
90static inline unsigned long dma_get_seg_boundary(struct device *dev)
91{
92 return dev->dma_parms ?
93 dev->dma_parms->segment_boundary_mask : 0xffffffff;
94}
95
96static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
97{
98 if (dev->dma_parms) {
99 dev->dma_parms->segment_boundary_mask = mask;
100 return 0;
101 } else
102 return -EIO;
103}
104
105/* flags for the coherent memory api */
106#define DMA_MEMORY_MAP 0x01
107#define DMA_MEMORY_IO 0x02
108#define DMA_MEMORY_INCLUDES_CHILDREN 0x04
109#define DMA_MEMORY_EXCLUSIVE 0x08
110
111#ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
112static inline int
113dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
114 dma_addr_t device_addr, size_t size, int flags)
115{
116 return 0;
117}
118
119static inline void
120dma_release_declared_memory(struct device *dev)
121{
122}
123
124static inline void *
125dma_mark_declared_memory_occupied(struct device *dev,
126 dma_addr_t device_addr, size_t size)
127{
128 return ERR_PTR(-EBUSY);
129}
130#endif
131
132/*
133 * Managed DMA API
134 */
135extern void *dmam_alloc_coherent(struct device *dev, size_t size,
136 dma_addr_t *dma_handle, gfp_t gfp);
137extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
138 dma_addr_t dma_handle);
139extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
140 dma_addr_t *dma_handle, gfp_t gfp);
141extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
142 dma_addr_t dma_handle);
143#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
144extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
145 dma_addr_t device_addr, size_t size,
146 int flags);
147extern void dmam_release_declared_memory(struct device *dev);
148#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
149static inline int dmam_declare_coherent_memory(struct device *dev,
150 dma_addr_t bus_addr, dma_addr_t device_addr,
151 size_t size, gfp_t gfp)
152{
153 return 0;
154}
155
156static inline void dmam_release_declared_memory(struct device *dev)
157{
158}
159#endif /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
160
161#ifndef CONFIG_HAVE_DMA_ATTRS
162struct dma_attrs;
163
164#define dma_map_single_attrs(dev, cpu_addr, size, dir, attrs) \
165 dma_map_single(dev, cpu_addr, size, dir)
166
167#define dma_unmap_single_attrs(dev, dma_addr, size, dir, attrs) \
168 dma_unmap_single(dev, dma_addr, size, dir)
169
170#define dma_map_sg_attrs(dev, sgl, nents, dir, attrs) \
171 dma_map_sg(dev, sgl, nents, dir)
172
173#define dma_unmap_sg_attrs(dev, sgl, nents, dir, attrs) \
174 dma_unmap_sg(dev, sgl, nents, dir)
175
176#endif /* CONFIG_HAVE_DMA_ATTRS */
177
178#endif