Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / arch / c6x / kernel / dma.c
blob9fff8be75f585a8bf961aa5173b0957bf0ab7d31
1 /*
2 * Copyright (C) 2011 Texas Instruments Incorporated
3 * Author: Mark Salter <msalter@redhat.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9 #include <linux/module.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/mm.h>
12 #include <linux/mm_types.h>
13 #include <linux/scatterlist.h>
15 #include <asm/cacheflush.h>
17 static void c6x_dma_sync(dma_addr_t handle, size_t size,
18 enum dma_data_direction dir)
20 unsigned long paddr = handle;
22 BUG_ON(!valid_dma_direction(dir));
24 switch (dir) {
25 case DMA_FROM_DEVICE:
26 L2_cache_block_invalidate(paddr, paddr + size);
27 break;
28 case DMA_TO_DEVICE:
29 L2_cache_block_writeback(paddr, paddr + size);
30 break;
31 case DMA_BIDIRECTIONAL:
32 L2_cache_block_writeback_invalidate(paddr, paddr + size);
33 break;
34 default:
35 break;
39 static dma_addr_t c6x_dma_map_page(struct device *dev, struct page *page,
40 unsigned long offset, size_t size, enum dma_data_direction dir,
41 unsigned long attrs)
43 dma_addr_t handle = virt_to_phys(page_address(page) + offset);
45 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
46 c6x_dma_sync(handle, size, dir);
48 return handle;
51 static void c6x_dma_unmap_page(struct device *dev, dma_addr_t handle,
52 size_t size, enum dma_data_direction dir, unsigned long attrs)
54 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
55 c6x_dma_sync(handle, size, dir);
58 static int c6x_dma_map_sg(struct device *dev, struct scatterlist *sglist,
59 int nents, enum dma_data_direction dir, unsigned long attrs)
61 struct scatterlist *sg;
62 int i;
64 for_each_sg(sglist, sg, nents, i) {
65 sg->dma_address = sg_phys(sg);
66 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
67 c6x_dma_sync(sg->dma_address, sg->length, dir);
70 return nents;
73 static void c6x_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
74 int nents, enum dma_data_direction dir, unsigned long attrs)
76 struct scatterlist *sg;
77 int i;
79 if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
80 return;
82 for_each_sg(sglist, sg, nents, i)
83 c6x_dma_sync(sg_dma_address(sg), sg->length, dir);
86 static void c6x_dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle,
87 size_t size, enum dma_data_direction dir)
89 c6x_dma_sync(handle, size, dir);
93 static void c6x_dma_sync_single_for_device(struct device *dev,
94 dma_addr_t handle, size_t size, enum dma_data_direction dir)
96 c6x_dma_sync(handle, size, dir);
100 static void c6x_dma_sync_sg_for_cpu(struct device *dev,
101 struct scatterlist *sglist, int nents,
102 enum dma_data_direction dir)
104 struct scatterlist *sg;
105 int i;
107 for_each_sg(sglist, sg, nents, i)
108 c6x_dma_sync_single_for_cpu(dev, sg_dma_address(sg),
109 sg->length, dir);
113 static void c6x_dma_sync_sg_for_device(struct device *dev,
114 struct scatterlist *sglist, int nents,
115 enum dma_data_direction dir)
117 struct scatterlist *sg;
118 int i;
120 for_each_sg(sglist, sg, nents, i)
121 c6x_dma_sync_single_for_device(dev, sg_dma_address(sg),
122 sg->length, dir);
126 const struct dma_map_ops c6x_dma_ops = {
127 .alloc = c6x_dma_alloc,
128 .free = c6x_dma_free,
129 .map_page = c6x_dma_map_page,
130 .unmap_page = c6x_dma_unmap_page,
131 .map_sg = c6x_dma_map_sg,
132 .unmap_sg = c6x_dma_unmap_sg,
133 .sync_single_for_device = c6x_dma_sync_single_for_device,
134 .sync_single_for_cpu = c6x_dma_sync_single_for_cpu,
135 .sync_sg_for_device = c6x_dma_sync_sg_for_device,
136 .sync_sg_for_cpu = c6x_dma_sync_sg_for_cpu,
138 EXPORT_SYMBOL(c6x_dma_ops);
140 /* Number of entries preallocated for DMA-API debugging */
141 #define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
143 static int __init dma_init(void)
145 dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
147 return 0;
149 fs_initcall(dma_init);