Blame view

kernel/linux-imx6_3.14.28/arch/arm64/mm/dma-mapping.c 2.99 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
  /*
   * SWIOTLB-based DMA API implementation
   *
   * Copyright (C) 2012 ARM Ltd.
   * Author: Catalin Marinas <catalin.marinas@arm.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #include <linux/gfp.h>
  #include <linux/export.h>
  #include <linux/slab.h>
  #include <linux/dma-mapping.h>
  #include <linux/dma-contiguous.h>
  #include <linux/vmalloc.h>
  #include <linux/swiotlb.h>
  
  #include <asm/cacheflush.h>
  
  struct dma_map_ops *dma_ops;
  EXPORT_SYMBOL(dma_ops);
  
  static void *arm64_swiotlb_alloc_coherent(struct device *dev, size_t size,
  					  dma_addr_t *dma_handle, gfp_t flags,
  					  struct dma_attrs *attrs)
  {
  	if (dev == NULL) {
  		WARN_ONCE(1, "Use an actual device structure for DMA allocation
  ");
  		return NULL;
  	}
  
  	if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
  	    dev->coherent_dma_mask <= DMA_BIT_MASK(32))
  		flags |= GFP_DMA32;
  	if (IS_ENABLED(CONFIG_DMA_CMA)) {
  		struct page *page;
  
  		size = PAGE_ALIGN(size);
  		page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
  							get_order(size));
  		if (!page)
  			return NULL;
  
  		*dma_handle = phys_to_dma(dev, page_to_phys(page));
  		return page_address(page);
  	} else {
  		return swiotlb_alloc_coherent(dev, size, dma_handle, flags);
  	}
  }
  
  static void arm64_swiotlb_free_coherent(struct device *dev, size_t size,
  					void *vaddr, dma_addr_t dma_handle,
  					struct dma_attrs *attrs)
  {
  	if (dev == NULL) {
  		WARN_ONCE(1, "Use an actual device structure for DMA allocation
  ");
  		return;
  	}
  
  	if (IS_ENABLED(CONFIG_DMA_CMA)) {
  		phys_addr_t paddr = dma_to_phys(dev, dma_handle);
  
  		dma_release_from_contiguous(dev,
  					phys_to_page(paddr),
  					size >> PAGE_SHIFT);
  	} else {
  		swiotlb_free_coherent(dev, size, vaddr, dma_handle);
  	}
  }
  
  static struct dma_map_ops arm64_swiotlb_dma_ops = {
  	.alloc = arm64_swiotlb_alloc_coherent,
  	.free = arm64_swiotlb_free_coherent,
  	.map_page = swiotlb_map_page,
  	.unmap_page = swiotlb_unmap_page,
  	.map_sg = swiotlb_map_sg_attrs,
  	.unmap_sg = swiotlb_unmap_sg_attrs,
  	.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
  	.sync_single_for_device = swiotlb_sync_single_for_device,
  	.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
  	.sync_sg_for_device = swiotlb_sync_sg_for_device,
  	.dma_supported = swiotlb_dma_supported,
  	.mapping_error = swiotlb_dma_mapping_error,
  };
  
  void __init arm64_swiotlb_init(void)
  {
  	dma_ops = &arm64_swiotlb_dma_ops;
  	swiotlb_init(1);
  }
  
  #define PREALLOC_DMA_DEBUG_ENTRIES	4096
  
  static int __init dma_debug_do_init(void)
  {
  	dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
  	return 0;
  }
  fs_initcall(dma_debug_do_init);