1/*
2 * Copyright (C) 2004 - 2007  Paul Mundt
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License.  See the file "COPYING" in the main directory of this archive
6 * for more details.
7 */
8#include <linux/mm.h>
9#include <linux/init.h>
10#include <linux/platform_device.h>
11#include <linux/dma-mapping.h>
12#include <linux/io.h>
13
14static int __init memchunk_setup(char *str)
15{
16	return 1; /* accept anything that begins with "memchunk." */
17}
18__setup("memchunk.", memchunk_setup);
19
20static void __init memchunk_cmdline_override(char *name, unsigned long *sizep)
21{
22	char *p = boot_command_line;
23	int k = strlen(name);
24
25	while ((p = strstr(p, "memchunk."))) {
26		p += 9; /* strlen("memchunk.") */
27		if (!strncmp(name, p, k) && p[k] == '=') {
28			p += k + 1;
29			*sizep = memparse(p, NULL);
30			pr_info("%s: forcing memory chunk size to 0x%08lx\n",
31				name, *sizep);
32			break;
33		}
34	}
35}
36
37int __init platform_resource_setup_memory(struct platform_device *pdev,
38					  char *name, unsigned long memsize)
39{
40	struct resource *r;
41	dma_addr_t dma_handle;
42	void *buf;
43
44	r = pdev->resource + pdev->num_resources - 1;
45	if (r->flags) {
46		pr_warn("%s: unable to find empty space for resource\n", name);
47		return -EINVAL;
48	}
49
50	memchunk_cmdline_override(name, &memsize);
51	if (!memsize)
52		return 0;
53
54	buf = dma_alloc_coherent(&pdev->dev, memsize, &dma_handle, GFP_KERNEL);
55	if (!buf) {
56		pr_warn("%s: unable to allocate memory\n", name);
57		return -ENOMEM;
58	}
59
60	r->flags = IORESOURCE_MEM;
61	r->start = dma_handle;
62	r->end = r->start + memsize - 1;
63	r->name = name;
64	return 0;
65}
66