tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2014-2015 ARM Ltd.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 */
16#ifndef __DMA_IOMMU_H
17#define __DMA_IOMMU_H
18
19#ifdef __KERNEL__
20#include <linux/types.h>
21#include <asm/errno.h>
22
23#ifdef CONFIG_IOMMU_DMA
24#include <linux/dma-mapping.h>
25#include <linux/iommu.h>
26#include <linux/msi.h>
27
28int iommu_dma_init(void);
29
30/* Domain management interface for IOMMU drivers */
31int iommu_get_dma_cookie(struct iommu_domain *domain);
32int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base);
33void iommu_put_dma_cookie(struct iommu_domain *domain);
34
35/* Setup call for arch DMA mapping code */
36int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
37 u64 size, struct device *dev);
38
39/* General helpers for DMA-API <-> IOMMU-API interaction */
40int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
41 unsigned long attrs);
42
43/*
44 * These implement the bulk of the relevant DMA mapping callbacks, but require
45 * the arch code to take care of attributes and cache maintenance
46 */
47struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
48 unsigned long attrs, int prot, dma_addr_t *handle,
49 void (*flush_page)(struct device *, const void *, phys_addr_t));
50void iommu_dma_free(struct device *dev, struct page **pages, size_t size,
51 dma_addr_t *handle);
52
53int iommu_dma_mmap(struct page **pages, size_t size, struct vm_area_struct *vma);
54
55dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page,
56 unsigned long offset, size_t size, int prot);
57int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg,
58 int nents, int prot);
59
60/*
61 * Arch code with no special attribute handling may use these
62 * directly as DMA mapping callbacks for simplicity
63 */
64void iommu_dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
65 enum dma_data_direction dir, unsigned long attrs);
66void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
67 enum dma_data_direction dir, unsigned long attrs);
68dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,
69 size_t size, enum dma_data_direction dir, unsigned long attrs);
70void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,
71 size_t size, enum dma_data_direction dir, unsigned long attrs);
72
73/* The DMA API isn't _quite_ the whole story, though... */
74/*
75 * iommu_dma_prepare_msi() - Map the MSI page in the IOMMU device
76 *
77 * The MSI page will be stored in @desc.
78 *
79 * Return: 0 on success otherwise an error describing the failure.
80 */
81int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr);
82
83/* Update the MSI message if required. */
84void iommu_dma_compose_msi_msg(struct msi_desc *desc,
85 struct msi_msg *msg);
86
87void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list);
88
89#else
90
91struct iommu_domain;
92struct msi_desc;
93struct msi_msg;
94struct device;
95
96static inline int iommu_dma_init(void)
97{
98 return 0;
99}
100
101static inline int iommu_get_dma_cookie(struct iommu_domain *domain)
102{
103 return -ENODEV;
104}
105
106static inline int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base)
107{
108 return -ENODEV;
109}
110
111static inline void iommu_put_dma_cookie(struct iommu_domain *domain)
112{
113}
114
115static inline int iommu_dma_prepare_msi(struct msi_desc *desc,
116 phys_addr_t msi_addr)
117{
118 return 0;
119}
120
121static inline void iommu_dma_compose_msi_msg(struct msi_desc *desc,
122 struct msi_msg *msg)
123{
124}
125
126static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list)
127{
128}
129
130#endif /* CONFIG_IOMMU_DMA */
131#endif /* __KERNEL__ */
132#endif /* __DMA_IOMMU_H */