xref: /openbmc/linux/arch/m68k/kernel/dma.c (revision 95298d63)
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)
21 void arch_dma_prep_coherent(struct page *page, size_t size)
22 {
23 	cache_push(page_to_phys(page), size);
24 }
25 
26 pgprot_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 
40 void *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 
56 void 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 
64 void 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 }
81