Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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-noncoherent.h>
10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/platform_device.h>
13#include <linux/scatterlist.h>
14#include <linux/slab.h>
15#include <linux/vmalloc.h>
16#include <linux/export.h>
17
18#include <asm/pgalloc.h>
19
20#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
21void arch_dma_prep_coherent(struct page *page, size_t size)
22{
23 cache_push(page_to_phys(page), size);
24}
25
26pgprot_t pgprot_dmacoherent(pgprot_t prot)
27{
28 if (CPU_IS_040_OR_060) {
29 pgprot_val(prot) &= ~_PAGE_CACHE040;
30 pgprot_val(prot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
31 } else {
32 pgprot_val(prot) |= _PAGE_NOCACHE030;
33 }
34 return prot;
35}
36#else
37
38#include <asm/cacheflush.h>
39
40void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
41 gfp_t gfp, unsigned long attrs)
42{
43 void *ret;
44
45 if (dev == NULL || (*dev->dma_mask < 0xffffffff))
46 gfp |= GFP_DMA;
47 ret = (void *)__get_free_pages(gfp, get_order(size));
48
49 if (ret != NULL) {
50 memset(ret, 0, size);
51 *dma_handle = virt_to_phys(ret);
52 }
53 return ret;
54}
55
56void arch_dma_free(struct device *dev, size_t size, void *vaddr,
57 dma_addr_t dma_handle, unsigned long attrs)
58{
59 free_pages((unsigned long)vaddr, get_order(size));
60}
61
62#endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
63
64void arch_sync_dma_for_device(phys_addr_t handle, size_t size,
65 enum dma_data_direction dir)
66{
67 switch (dir) {
68 case DMA_BIDIRECTIONAL:
69 case DMA_TO_DEVICE:
70 cache_push(handle, size);
71 break;
72 case DMA_FROM_DEVICE:
73 cache_clear(handle, size);
74 break;
75 default:
76 pr_err_ratelimited("dma_sync_single_for_device: unsupported dir %u\n",
77 dir);
78 break;
79 }
80}