tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef _ASM_I386_DMA_MAPPING_H
2#define _ASM_I386_DMA_MAPPING_H
3
4#include <linux/mm.h>
5
6#include <asm/cache.h>
7#include <asm/io.h>
8#include <asm/scatterlist.h>
9#include <asm/bug.h>
10
11#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
12#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
13
14void *dma_alloc_coherent(struct device *dev, size_t size,
15 dma_addr_t *dma_handle, gfp_t flag);
16
17void dma_free_coherent(struct device *dev, size_t size,
18 void *vaddr, dma_addr_t dma_handle);
19
20static inline dma_addr_t
21dma_map_single(struct device *dev, void *ptr, size_t size,
22 enum dma_data_direction direction)
23{
24 BUG_ON(!valid_dma_direction(direction));
25 WARN_ON(size == 0);
26 flush_write_buffers();
27 return virt_to_phys(ptr);
28}
29
30static inline void
31dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
32 enum dma_data_direction direction)
33{
34 BUG_ON(!valid_dma_direction(direction));
35}
36
37static inline int
38dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
39 enum dma_data_direction direction)
40{
41 int i;
42
43 BUG_ON(!valid_dma_direction(direction));
44 WARN_ON(nents == 0 || sg[0].length == 0);
45
46 for (i = 0; i < nents; i++ ) {
47 BUG_ON(!sg[i].page);
48
49 sg[i].dma_address = page_to_phys(sg[i].page) + sg[i].offset;
50 }
51
52 flush_write_buffers();
53 return nents;
54}
55
56static inline dma_addr_t
57dma_map_page(struct device *dev, struct page *page, unsigned long offset,
58 size_t size, enum dma_data_direction direction)
59{
60 BUG_ON(!valid_dma_direction(direction));
61 return page_to_phys(page) + offset;
62}
63
64static inline void
65dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
66 enum dma_data_direction direction)
67{
68 BUG_ON(!valid_dma_direction(direction));
69}
70
71
72static inline void
73dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
74 enum dma_data_direction direction)
75{
76 BUG_ON(!valid_dma_direction(direction));
77}
78
79static inline void
80dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size,
81 enum dma_data_direction direction)
82{
83}
84
85static inline void
86dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, size_t size,
87 enum dma_data_direction direction)
88{
89 flush_write_buffers();
90}
91
92static inline void
93dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle,
94 unsigned long offset, size_t size,
95 enum dma_data_direction direction)
96{
97}
98
99static inline void
100dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
101 unsigned long offset, size_t size,
102 enum dma_data_direction direction)
103{
104 flush_write_buffers();
105}
106
107static inline void
108dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
109 enum dma_data_direction direction)
110{
111}
112
113static inline void
114dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
115 enum dma_data_direction direction)
116{
117 flush_write_buffers();
118}
119
120static inline int
121dma_mapping_error(dma_addr_t dma_addr)
122{
123 return 0;
124}
125
126extern int forbid_dac;
127
128static inline int
129dma_supported(struct device *dev, u64 mask)
130{
131 /*
132 * we fall back to GFP_DMA when the mask isn't all 1s,
133 * so we can't guarantee allocations that must be
134 * within a tighter range than GFP_DMA..
135 */
136 if(mask < 0x00ffffff)
137 return 0;
138
139 /* Work around chipset bugs */
140 if (forbid_dac > 0 && mask > 0xffffffffULL)
141 return 0;
142
143 return 1;
144}
145
146static inline int
147dma_set_mask(struct device *dev, u64 mask)
148{
149 if(!dev->dma_mask || !dma_supported(dev, mask))
150 return -EIO;
151
152 *dev->dma_mask = mask;
153
154 return 0;
155}
156
157static inline int
158dma_get_cache_alignment(void)
159{
160 /* no easy way to get cache size on all x86, so return the
161 * maximum possible, to be safe */
162 return (1 << INTERNODE_CACHE_SHIFT);
163}
164
165#define dma_is_consistent(d, h) (1)
166
167static inline void
168dma_cache_sync(struct device *dev, void *vaddr, size_t size,
169 enum dma_data_direction direction)
170{
171 flush_write_buffers();
172}
173
174#define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
175extern int
176dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
177 dma_addr_t device_addr, size_t size, int flags);
178
179extern void
180dma_release_declared_memory(struct device *dev);
181
182extern void *
183dma_mark_declared_memory_occupied(struct device *dev,
184 dma_addr_t device_addr, size_t size);
185
186#endif