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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
4 *
5 * Provide default implementations of the DMA mapping callbacks for
6 * busses using the iommu infrastructure
7 */
8
9#include <linux/export.h>
10#include <asm/iommu.h>
11
12/*
13 * Generic iommu implementation
14 */
15
16/* Allocates a contiguous real buffer and creates mappings over it.
17 * Returns the virtual address of the buffer and sets dma_handle
18 * to the dma address (mapping) of the first page.
19 */
20static void *dma_iommu_alloc_coherent(struct device *dev, size_t size,
21 dma_addr_t *dma_handle, gfp_t flag,
22 unsigned long attrs)
23{
24 return iommu_alloc_coherent(dev, get_iommu_table_base(dev), size,
25 dma_handle, dev->coherent_dma_mask, flag,
26 dev_to_node(dev));
27}
28
29static void dma_iommu_free_coherent(struct device *dev, size_t size,
30 void *vaddr, dma_addr_t dma_handle,
31 unsigned long attrs)
32{
33 iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, dma_handle);
34}
35
36/* Creates TCEs for a user provided buffer. The user buffer must be
37 * contiguous real kernel storage (not vmalloc). The address passed here
38 * comprises a page address and offset into that page. The dma_addr_t
39 * returned will point to the same byte within the page as was passed in.
40 */
41static dma_addr_t dma_iommu_map_page(struct device *dev, struct page *page,
42 unsigned long offset, size_t size,
43 enum dma_data_direction direction,
44 unsigned long attrs)
45{
46 return iommu_map_page(dev, get_iommu_table_base(dev), page, offset,
47 size, device_to_mask(dev), direction, attrs);
48}
49
50
51static void dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle,
52 size_t size, enum dma_data_direction direction,
53 unsigned long attrs)
54{
55 iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, direction,
56 attrs);
57}
58
59
60static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
61 int nelems, enum dma_data_direction direction,
62 unsigned long attrs)
63{
64 return ppc_iommu_map_sg(dev, get_iommu_table_base(dev), sglist, nelems,
65 device_to_mask(dev), direction, attrs);
66}
67
68static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist,
69 int nelems, enum dma_data_direction direction,
70 unsigned long attrs)
71{
72 ppc_iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems,
73 direction, attrs);
74}
75
76/* We support DMA to/from any memory page via the iommu */
77int dma_iommu_dma_supported(struct device *dev, u64 mask)
78{
79 struct iommu_table *tbl = get_iommu_table_base(dev);
80
81 if (!tbl) {
82 dev_info(dev, "Warning: IOMMU dma not supported: mask 0x%08llx"
83 ", table unavailable\n", mask);
84 return 0;
85 }
86
87 if (tbl->it_offset > (mask >> tbl->it_page_shift)) {
88 dev_info(dev, "Warning: IOMMU offset too big for device mask\n");
89 dev_info(dev, "mask: 0x%08llx, table offset: 0x%08lx\n",
90 mask, tbl->it_offset << tbl->it_page_shift);
91 return 0;
92 } else
93 return 1;
94}
95
96static u64 dma_iommu_get_required_mask(struct device *dev)
97{
98 struct iommu_table *tbl = get_iommu_table_base(dev);
99 u64 mask;
100 if (!tbl)
101 return 0;
102
103 mask = 1ULL < (fls_long(tbl->it_offset + tbl->it_size) - 1);
104 mask += mask - 1;
105
106 return mask;
107}
108
109int dma_iommu_mapping_error(struct device *dev, dma_addr_t dma_addr)
110{
111 return dma_addr == IOMMU_MAPPING_ERROR;
112}
113
114struct dma_map_ops dma_iommu_ops = {
115 .alloc = dma_iommu_alloc_coherent,
116 .free = dma_iommu_free_coherent,
117 .mmap = dma_nommu_mmap_coherent,
118 .map_sg = dma_iommu_map_sg,
119 .unmap_sg = dma_iommu_unmap_sg,
120 .dma_supported = dma_iommu_dma_supported,
121 .map_page = dma_iommu_map_page,
122 .unmap_page = dma_iommu_unmap_page,
123 .get_required_mask = dma_iommu_get_required_mask,
124 .mapping_error = dma_iommu_mapping_error,
125};
126EXPORT_SYMBOL(dma_iommu_ops);
1/*
2 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
3 *
4 * Provide default implementations of the DMA mapping callbacks for
5 * busses using the iommu infrastructure
6 */
7
8#include <linux/export.h>
9#include <asm/iommu.h>
10
11/*
12 * Generic iommu implementation
13 */
14
15/* Allocates a contiguous real buffer and creates mappings over it.
16 * Returns the virtual address of the buffer and sets dma_handle
17 * to the dma address (mapping) of the first page.
18 */
19static void *dma_iommu_alloc_coherent(struct device *dev, size_t size,
20 dma_addr_t *dma_handle, gfp_t flag,
21 struct dma_attrs *attrs)
22{
23 return iommu_alloc_coherent(dev, get_iommu_table_base(dev), size,
24 dma_handle, dev->coherent_dma_mask, flag,
25 dev_to_node(dev));
26}
27
28static void dma_iommu_free_coherent(struct device *dev, size_t size,
29 void *vaddr, dma_addr_t dma_handle,
30 struct dma_attrs *attrs)
31{
32 iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, dma_handle);
33}
34
35/* Creates TCEs for a user provided buffer. The user buffer must be
36 * contiguous real kernel storage (not vmalloc). The address passed here
37 * comprises a page address and offset into that page. The dma_addr_t
38 * returned will point to the same byte within the page as was passed in.
39 */
40static dma_addr_t dma_iommu_map_page(struct device *dev, struct page *page,
41 unsigned long offset, size_t size,
42 enum dma_data_direction direction,
43 struct dma_attrs *attrs)
44{
45 return iommu_map_page(dev, get_iommu_table_base(dev), page, offset,
46 size, device_to_mask(dev), direction, attrs);
47}
48
49
50static void dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle,
51 size_t size, enum dma_data_direction direction,
52 struct dma_attrs *attrs)
53{
54 iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, direction,
55 attrs);
56}
57
58
59static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
60 int nelems, enum dma_data_direction direction,
61 struct dma_attrs *attrs)
62{
63 return iommu_map_sg(dev, get_iommu_table_base(dev), sglist, nelems,
64 device_to_mask(dev), direction, attrs);
65}
66
67static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist,
68 int nelems, enum dma_data_direction direction,
69 struct dma_attrs *attrs)
70{
71 iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems, direction,
72 attrs);
73}
74
75/* We support DMA to/from any memory page via the iommu */
76static int dma_iommu_dma_supported(struct device *dev, u64 mask)
77{
78 struct iommu_table *tbl = get_iommu_table_base(dev);
79
80 if (!tbl) {
81 dev_info(dev, "Warning: IOMMU dma not supported: mask 0x%08llx"
82 ", table unavailable\n", mask);
83 return 0;
84 }
85
86 if (tbl->it_offset > (mask >> tbl->it_page_shift)) {
87 dev_info(dev, "Warning: IOMMU offset too big for device mask\n");
88 dev_info(dev, "mask: 0x%08llx, table offset: 0x%08lx\n",
89 mask, tbl->it_offset << tbl->it_page_shift);
90 return 0;
91 } else
92 return 1;
93}
94
95static u64 dma_iommu_get_required_mask(struct device *dev)
96{
97 struct iommu_table *tbl = get_iommu_table_base(dev);
98 u64 mask;
99 if (!tbl)
100 return 0;
101
102 mask = 1ULL < (fls_long(tbl->it_offset + tbl->it_size) - 1);
103 mask += mask - 1;
104
105 return mask;
106}
107
108struct dma_map_ops dma_iommu_ops = {
109 .alloc = dma_iommu_alloc_coherent,
110 .free = dma_iommu_free_coherent,
111 .mmap = dma_direct_mmap_coherent,
112 .map_sg = dma_iommu_map_sg,
113 .unmap_sg = dma_iommu_unmap_sg,
114 .dma_supported = dma_iommu_dma_supported,
115 .map_page = dma_iommu_map_page,
116 .unmap_page = dma_iommu_unmap_page,
117 .get_required_mask = dma_iommu_get_required_mask,
118};
119EXPORT_SYMBOL(dma_iommu_ops);