Linux Audio

Check our new training course

Loading...
v5.4
 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_warning("%s: unable to find empty space for resource\n",
47			name);
48		return -EINVAL;
49	}
50
51	memchunk_cmdline_override(name, &memsize);
52	if (!memsize)
53		return 0;
54
55	buf = dma_alloc_coherent(&pdev->dev, memsize, &dma_handle, GFP_KERNEL);
56	if (!buf) {
57		pr_warning("%s: unable to allocate memory\n", name);
58		return -ENOMEM;
59	}
60
61	memset(buf, 0, memsize);
62
63	r->flags = IORESOURCE_MEM;
64	r->start = dma_handle;
65	r->end = r->start + memsize - 1;
66	r->name = name;
67	return 0;
68}
v4.6
  1/*
  2 * arch/sh/mm/consistent.c
  3 *
  4 * Copyright (C) 2004 - 2007  Paul Mundt
  5 *
  6 * Declared coherent memory functions based on arch/x86/kernel/pci-dma_32.c
  7 *
  8 * This file is subject to the terms and conditions of the GNU General Public
  9 * License.  See the file "COPYING" in the main directory of this archive
 10 * for more details.
 11 */
 12#include <linux/mm.h>
 13#include <linux/init.h>
 14#include <linux/platform_device.h>
 15#include <linux/dma-mapping.h>
 16#include <linux/dma-debug.h>
 17#include <linux/io.h>
 18#include <linux/module.h>
 19#include <linux/gfp.h>
 20#include <asm/cacheflush.h>
 21#include <asm/addrspace.h>
 22
 23#define PREALLOC_DMA_DEBUG_ENTRIES	4096
 24
 25struct dma_map_ops *dma_ops;
 26EXPORT_SYMBOL(dma_ops);
 27
 28static int __init dma_init(void)
 29{
 30	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
 31	return 0;
 32}
 33fs_initcall(dma_init);
 34
 35void *dma_generic_alloc_coherent(struct device *dev, size_t size,
 36				 dma_addr_t *dma_handle, gfp_t gfp,
 37				 struct dma_attrs *attrs)
 38{
 39	void *ret, *ret_nocache;
 40	int order = get_order(size);
 41
 42	gfp |= __GFP_ZERO;
 43
 44	ret = (void *)__get_free_pages(gfp, order);
 45	if (!ret)
 46		return NULL;
 47
 48	/*
 49	 * Pages from the page allocator may have data present in
 50	 * cache. So flush the cache before using uncached memory.
 51	 */
 52	dma_cache_sync(dev, ret, size, DMA_BIDIRECTIONAL);
 53
 54	ret_nocache = (void __force *)ioremap_nocache(virt_to_phys(ret), size);
 55	if (!ret_nocache) {
 56		free_pages((unsigned long)ret, order);
 57		return NULL;
 58	}
 59
 60	split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order);
 61
 62	*dma_handle = virt_to_phys(ret);
 63
 64	return ret_nocache;
 65}
 66
 67void dma_generic_free_coherent(struct device *dev, size_t size,
 68			       void *vaddr, dma_addr_t dma_handle,
 69			       struct dma_attrs *attrs)
 70{
 71	int order = get_order(size);
 72	unsigned long pfn = dma_handle >> PAGE_SHIFT;
 73	int k;
 74
 75	for (k = 0; k < (1 << order); k++)
 76		__free_pages(pfn_to_page(pfn + k), 0);
 77
 78	iounmap(vaddr);
 79}
 80
 81void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 82		    enum dma_data_direction direction)
 83{
 84	void *addr;
 85
 86	addr = __in_29bit_mode() ?
 87	       (void *)CAC_ADDR((unsigned long)vaddr) : vaddr;
 88
 89	switch (direction) {
 90	case DMA_FROM_DEVICE:		/* invalidate only */
 91		__flush_invalidate_region(addr, size);
 92		break;
 93	case DMA_TO_DEVICE:		/* writeback only */
 94		__flush_wback_region(addr, size);
 95		break;
 96	case DMA_BIDIRECTIONAL:		/* writeback and invalidate */
 97		__flush_purge_region(addr, size);
 98		break;
 99	default:
100		BUG();
101	}
102}
103EXPORT_SYMBOL(dma_cache_sync);
104
105static int __init memchunk_setup(char *str)
106{
107	return 1; /* accept anything that begins with "memchunk." */
108}
109__setup("memchunk.", memchunk_setup);
110
111static void __init memchunk_cmdline_override(char *name, unsigned long *sizep)
112{
113	char *p = boot_command_line;
114	int k = strlen(name);
115
116	while ((p = strstr(p, "memchunk."))) {
117		p += 9; /* strlen("memchunk.") */
118		if (!strncmp(name, p, k) && p[k] == '=') {
119			p += k + 1;
120			*sizep = memparse(p, NULL);
121			pr_info("%s: forcing memory chunk size to 0x%08lx\n",
122				name, *sizep);
123			break;
124		}
125	}
126}
127
128int __init platform_resource_setup_memory(struct platform_device *pdev,
129					  char *name, unsigned long memsize)
130{
131	struct resource *r;
132	dma_addr_t dma_handle;
133	void *buf;
134
135	r = pdev->resource + pdev->num_resources - 1;
136	if (r->flags) {
137		pr_warning("%s: unable to find empty space for resource\n",
138			name);
139		return -EINVAL;
140	}
141
142	memchunk_cmdline_override(name, &memsize);
143	if (!memsize)
144		return 0;
145
146	buf = dma_alloc_coherent(NULL, memsize, &dma_handle, GFP_KERNEL);
147	if (!buf) {
148		pr_warning("%s: unable to allocate memory\n", name);
149		return -ENOMEM;
150	}
151
152	memset(buf, 0, memsize);
153
154	r->flags = IORESOURCE_MEM;
155	r->start = dma_handle;
156	r->end = r->start + memsize - 1;
157	r->name = name;
158	return 0;
159}