1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file COPYING in the main directory of this archive
4 * for more details.
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/vmalloc.h>
13
14#include <asm/pgalloc.h>
15#include <asm/scatterlist.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
69inline void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
70				       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 = page_to_phys(sg->page) + sg->offset;
125		dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
126	}
127	return nents;
128}
129EXPORT_SYMBOL(dma_map_sg);
130