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) 2012 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 __ASM_DMA_MAPPING_H
17#define __ASM_DMA_MAPPING_H
18
19#ifdef __KERNEL__
20
21#include <linux/acpi.h>
22#include <linux/types.h>
23#include <linux/vmalloc.h>
24
25#include <xen/xen.h>
26#include <asm/xen/hypervisor.h>
27
28#define DMA_ERROR_CODE (~(dma_addr_t)0)
29extern struct dma_map_ops *dma_ops;
30extern struct dma_map_ops dummy_dma_ops;
31
32static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
33{
34 if (unlikely(!dev))
35 return dma_ops;
36 else if (dev->archdata.dma_ops)
37 return dev->archdata.dma_ops;
38 else if (acpi_disabled)
39 return dma_ops;
40
41 /*
42 * When ACPI is enabled, if arch_set_dma_ops is not called,
43 * we will disable device DMA capability by setting it
44 * to dummy_dma_ops.
45 */
46 return &dummy_dma_ops;
47}
48
49static inline struct dma_map_ops *get_dma_ops(struct device *dev)
50{
51 if (xen_initial_domain())
52 return xen_dma_ops;
53 else
54 return __generic_dma_ops(dev);
55}
56
57static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
58 struct iommu_ops *iommu, bool coherent)
59{
60 if (!acpi_disabled && !dev->archdata.dma_ops)
61 dev->archdata.dma_ops = dma_ops;
62
63 dev->archdata.dma_coherent = coherent;
64}
65#define arch_setup_dma_ops arch_setup_dma_ops
66
67/* do not use this function in a driver */
68static inline bool is_device_dma_coherent(struct device *dev)
69{
70 if (!dev)
71 return false;
72 return dev->archdata.dma_coherent;
73}
74
75#include <asm-generic/dma-mapping-common.h>
76
77static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
78{
79 return (dma_addr_t)paddr;
80}
81
82static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
83{
84 return (phys_addr_t)dev_addr;
85}
86
87static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
88{
89 if (!dev->dma_mask)
90 return false;
91
92 return addr + size - 1 <= *dev->dma_mask;
93}
94
95static inline void dma_mark_clean(void *addr, size_t size)
96{
97}
98
99#endif /* __KERNEL__ */
100#endif /* __ASM_DMA_MAPPING_H */