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/types.h>
22#include <linux/vmalloc.h>
23
24#include <xen/xen.h>
25#include <asm/xen/hypervisor.h>
26
27#define DMA_ERROR_CODE (~(dma_addr_t)0)
28extern struct dma_map_ops dummy_dma_ops;
29
30static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
31{
32 if (dev && dev->archdata.dma_ops)
33 return dev->archdata.dma_ops;
34
35 /*
36 * We expect no ISA devices, and all other DMA masters are expected to
37 * have someone call arch_setup_dma_ops at device creation time.
38 */
39 return &dummy_dma_ops;
40}
41
42static inline struct dma_map_ops *get_dma_ops(struct device *dev)
43{
44 if (xen_initial_domain())
45 return xen_dma_ops;
46 else
47 return __generic_dma_ops(dev);
48}
49
50void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
51 const struct iommu_ops *iommu, bool coherent);
52#define arch_setup_dma_ops arch_setup_dma_ops
53
54#ifdef CONFIG_IOMMU_DMA
55void arch_teardown_dma_ops(struct device *dev);
56#define arch_teardown_dma_ops arch_teardown_dma_ops
57#endif
58
59/* do not use this function in a driver */
60static inline bool is_device_dma_coherent(struct device *dev)
61{
62 if (!dev)
63 return false;
64 return dev->archdata.dma_coherent;
65}
66
67static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
68{
69 dma_addr_t dev_addr = (dma_addr_t)paddr;
70
71 return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
72}
73
74static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
75{
76 phys_addr_t paddr = (phys_addr_t)dev_addr;
77
78 return paddr + ((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
79}
80
81static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
82{
83 if (!dev->dma_mask)
84 return false;
85
86 return addr + size - 1 <= *dev->dma_mask;
87}
88
89static inline void dma_mark_clean(void *addr, size_t size)
90{
91}
92
93/* Override for dma_max_pfn() */
94static inline unsigned long dma_max_pfn(struct device *dev)
95{
96 dma_addr_t dma_max = (dma_addr_t)*dev->dma_mask;
97
98 return (ulong)dma_to_phys(dev, dma_max) >> PAGE_SHIFT;
99}
100#define dma_max_pfn(dev) dma_max_pfn(dev)
101
102#endif /* __KERNEL__ */
103#endif /* __ASM_DMA_MAPPING_H */