Merge branch 'akpm' (patches from Andrew)
[linux-2.6-microblaze.git] / arch / nios2 / mm / dma-mapping.c
1 /*
2  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
3  * Copyright (C) 2009 Wind River Systems Inc
4  *  Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
5  *
6  * Based on DMA code from MIPS.
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
13 #include <linux/types.h>
14 #include <linux/mm.h>
15 #include <linux/string.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/io.h>
18 #include <linux/cache.h>
19 #include <asm/cacheflush.h>
20
21 void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
22                 enum dma_data_direction dir)
23 {
24         void *vaddr = phys_to_virt(paddr);
25
26         switch (dir) {
27         case DMA_FROM_DEVICE:
28                 invalidate_dcache_range((unsigned long)vaddr,
29                         (unsigned long)(vaddr + size));
30                 break;
31         case DMA_TO_DEVICE:
32                 /*
33                  * We just need to flush the caches here , but Nios2 flush
34                  * instruction will do both writeback and invalidate.
35                  */
36         case DMA_BIDIRECTIONAL: /* flush and invalidate */
37                 flush_dcache_range((unsigned long)vaddr,
38                         (unsigned long)(vaddr + size));
39                 break;
40         default:
41                 BUG();
42         }
43 }
44
45 void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
46                 enum dma_data_direction dir)
47 {
48         void *vaddr = phys_to_virt(paddr);
49
50         switch (dir) {
51         case DMA_BIDIRECTIONAL:
52         case DMA_FROM_DEVICE:
53                 invalidate_dcache_range((unsigned long)vaddr,
54                         (unsigned long)(vaddr + size));
55                 break;
56         case DMA_TO_DEVICE:
57                 break;
58         default:
59                 BUG();
60         }
61 }
62
63 void arch_dma_prep_coherent(struct page *page, size_t size)
64 {
65         unsigned long start = (unsigned long)page_address(page);
66
67         flush_dcache_range(start, start + size);
68 }
69
70 void *arch_dma_set_uncached(void *ptr, size_t size)
71 {
72         unsigned long addr = (unsigned long)ptr;
73
74         addr |= CONFIG_NIOS2_IO_REGION_BASE;
75
76         return (void *)ptr;
77 }