1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#undef DEBUG
#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
#include <asm/pgalloc.h>
#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t flag)
{
struct page *page, **map;
pgprot_t pgprot;
void *addr;
int i, order;
pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
size = PAGE_ALIGN(size);
order = get_order(size);
page = alloc_pages(flag, order);
if (!page)
return NULL;
*handle = page_to_phys(page);
map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
if (!map) {
__free_pages(page, order);
return NULL;
}
split_page(page, order);
order = 1 << order;
size >>= PAGE_SHIFT;
map[0] = page;
for (i = 1; i < size; i++)
map[i] = page + i;
for (; i < order; i++)
__free_page(page + i);
pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
if (CPU_IS_040_OR_060)
pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
else
pgprot_val(pgprot) |= _PAGE_NOCACHE030;
addr = vmap(map, size, VM_MAP, pgprot);
kfree(map);
return addr;
}
void dma_free_coherent(struct device *dev, size_t size,
void *addr, dma_addr_t handle)
{
pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
vfree(addr);
}
#else
#include <asm/cacheflush.h>
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp)
{
void *ret;
/* ignore region specifiers */
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
if (dev == NULL || (*dev->dma_mask < 0xffffffff))
gfp |= GFP_DMA;
ret = (void *)__get_free_pages(gfp, get_order(size));
if (ret != NULL) {
memset(ret, 0, size);
*dma_handle = virt_to_phys(ret);
}
return ret;
}
void dma_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
#endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
EXPORT_SYMBOL(dma_alloc_coherent);
EXPORT_SYMBOL(dma_free_coherent);
void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
switch (dir) {
case DMA_BIDIRECTIONAL:
case DMA_TO_DEVICE:
cache_push(handle, size);
break;
case DMA_FROM_DEVICE:
cache_clear(handle, size);
break;
default:
if (printk_ratelimit())
printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
break;
}
}
EXPORT_SYMBOL(dma_sync_single_for_device);
void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist,
int nents, enum dma_data_direction dir)
{
int i;
struct scatterlist *sg;
for_each_sg(sglist, sg, nents, i) {
dma_sync_single_for_device(dev, sg->dma_address, sg->length,
dir);
}
}
EXPORT_SYMBOL(dma_sync_sg_for_device);
dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
enum dma_data_direction dir)
{
dma_addr_t handle = virt_to_bus(addr);
dma_sync_single_for_device(dev, handle, size, dir);
return handle;
}
EXPORT_SYMBOL(dma_map_single);
dma_addr_t dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
dma_addr_t handle = page_to_phys(page) + offset;
dma_sync_single_for_device(dev, handle, size, dir);
return handle;
}
EXPORT_SYMBOL(dma_map_page);
int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
enum dma_data_direction dir)
{
int i;
struct scatterlist *sg;
for_each_sg(sglist, sg, nents, i) {
sg->dma_address = sg_phys(sg);
dma_sync_single_for_device(dev, sg->dma_address, sg->length,
dir);
}
return nents;
}
EXPORT_SYMBOL(dma_map_sg);
|
