1/*
2 * Copyright (C) 2001 David J. Mckay (david.mckay@st.com)
3 * Copyright (C) 2003 Paul Mundt (lethal@linux-sh.org)
4 *
5 * May be copied or modified under the terms of the GNU General Public
6 * License.  See linux/COPYING for more information.
7 *
8 * Dynamic DMA mapping support.
9 */
10#include <linux/types.h>
11#include <linux/mm.h>
12#include <linux/string.h>
13#include <linux/pci.h>
14#include <asm/io.h>
15
16void *consistent_alloc(struct pci_dev *hwdev, size_t size,
17			   dma_addr_t *dma_handle)
18{
19	void *ret;
20	int gfp = GFP_ATOMIC;
21        void *vp;
22
23	if (hwdev == NULL || hwdev->dma_mask != 0xffffffff)
24		gfp |= GFP_DMA;
25
26	ret = (void *)__get_free_pages(gfp, get_order(size));
27
28	/* now call our friend ioremap_nocache to give us an uncached area */
29        vp = ioremap_nocache(virt_to_phys(ret), size);
30
31	if (vp != NULL) {
32		memset(vp, 0, size);
33		*dma_handle = virt_to_bus(ret);
34		dma_cache_wback_inv((unsigned long)ret, size);
35	}
36
37	return vp;
38}
39
40void consistent_free(struct pci_dev *hwdev, size_t size,
41			 void *vaddr, dma_addr_t dma_handle)
42{
43	void *alloc;
44
45	alloc = bus_to_virt((unsigned long)dma_handle);
46	free_pages((unsigned long)alloc, get_order(size));
47
48	iounmap(vaddr);
49}
50