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5
6
7#undef DEBUG
8
9#include <linux/dma-mapping.h>
10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/scatterlist.h>
13#include <linux/vmalloc.h>
14
15#include <asm/pgalloc.h>
16
17void *dma_alloc_coherent(struct device *dev, size_t size,
18 dma_addr_t *handle, gfp_t flag)
19{
20 struct page *page, **map;
21 pgprot_t pgprot;
22 void *addr;
23 int i, order;
24
25 pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
26
27 size = PAGE_ALIGN(size);
28 order = get_order(size);
29
30 page = alloc_pages(flag, order);
31 if (!page)
32 return NULL;
33
34 *handle = page_to_phys(page);
35 map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
36 if (!map) {
37 __free_pages(page, order);
38 return NULL;
39 }
40 split_page(page, order);
41
42 order = 1 << order;
43 size >>= PAGE_SHIFT;
44 map[0] = page;
45 for (i = 1; i < size; i++)
46 map[i] = page + i;
47 for (; i < order; i++)
48 __free_page(page + i);
49 pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
50 if (CPU_IS_040_OR_060)
51 pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
52 else
53 pgprot_val(pgprot) |= _PAGE_NOCACHE030;
54 addr = vmap(map, size, VM_MAP, pgprot);
55 kfree(map);
56
57 return addr;
58}
59EXPORT_SYMBOL(dma_alloc_coherent);
60
61void dma_free_coherent(struct device *dev, size_t size,
62 void *addr, dma_addr_t handle)
63{
64 pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
65 vfree(addr);
66}
67EXPORT_SYMBOL(dma_free_coherent);
68
69void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
70 size_t size, enum dma_data_direction dir)
71{
72 switch (dir) {
73 case DMA_TO_DEVICE:
74 cache_push(handle, size);
75 break;
76 case DMA_FROM_DEVICE:
77 cache_clear(handle, size);
78 break;
79 default:
80 if (printk_ratelimit())
81 printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
82 break;
83 }
84}
85EXPORT_SYMBOL(dma_sync_single_for_device);
86
87void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
88 enum dma_data_direction dir)
89{
90 int i;
91
92 for (i = 0; i < nents; sg++, i++)
93 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
94}
95EXPORT_SYMBOL(dma_sync_sg_for_device);
96
97dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
98 enum dma_data_direction dir)
99{
100 dma_addr_t handle = virt_to_bus(addr);
101
102 dma_sync_single_for_device(dev, handle, size, dir);
103 return handle;
104}
105EXPORT_SYMBOL(dma_map_single);
106
107dma_addr_t dma_map_page(struct device *dev, struct page *page,
108 unsigned long offset, size_t size,
109 enum dma_data_direction dir)
110{
111 dma_addr_t handle = page_to_phys(page) + offset;
112
113 dma_sync_single_for_device(dev, handle, size, dir);
114 return handle;
115}
116EXPORT_SYMBOL(dma_map_page);
117
118int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
119 enum dma_data_direction dir)
120{
121 int i;
122
123 for (i = 0; i < nents; sg++, i++) {
124 sg->dma_address = sg_phys(sg);
125 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
126 }
127 return nents;
128}
129EXPORT_SYMBOL(dma_map_sg);
130
