summaryrefslogtreecommitdiffstats
path: root/arch/x86/include/asm/dma-mapping.h
blob: f9c67e83f6488844902132f7ca7dffcb3cb08489 (plain)
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
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
#ifndef _ASM_X86_DMA_MAPPING_H
#define _ASM_X86_DMA_MAPPING_H

/*
 * IOMMU interface. See Documentation/PCI/PCI-DMA-mapping.txt and
 * Documentation/DMA-API.txt for documentation.
 */

#include <linux/kmemcheck.h>
#include <linux/scatterlist.h>
#include <linux/dma-debug.h>
#include <linux/dma-attrs.h>
#include <asm/io.h>
#include <asm/swiotlb.h>
#include <asm-generic/dma-coherent.h>

#ifdef CONFIG_ISA
# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
#else
# define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
#endif

#define DMA_ERROR_CODE	0

extern int iommu_merge;
extern struct device x86_dma_fallback_dev;
extern int panic_on_overflow;

extern struct dma_map_ops *dma_ops;

static inline struct dma_map_ops *get_dma_ops(struct device *dev)
{
#ifdef CONFIG_X86_32
	return dma_ops;
#else
	if (unlikely(!dev) || !dev->archdata.dma_ops)
		return dma_ops;
	else
		return dev->archdata.dma_ops;
#endif
}

#include <asm-generic/dma-mapping-common.h>

/* Make sure we keep the same behaviour */
static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
	struct dma_map_ops *ops = get_dma_ops(dev);
	if (ops->mapping_error)
		return ops->mapping_error(dev, dma_addr);

	return (dma_addr == DMA_ERROR_CODE);
}

#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
#define dma_is_consistent(d, h)	(1)

extern int dma_supported(struct device *hwdev, u64 mask);
extern int dma_set_mask(struct device *dev, u64 mask);

extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
					dma_addr_t *dma_addr, gfp_t flag);

static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
{
	if (!dev->dma_mask)
		return 0;

	return addr + size - 1 <= *dev->dma_mask;
}

static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
	return paddr;
}

static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
{
	return daddr;
}

static inline void
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
	enum dma_data_direction dir)
{
	flush_write_buffers();
}

static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
						    gfp_t gfp)
{
	unsigned long dma_mask = 0;

	dma_mask = dev->coherent_dma_mask;
	if (!dma_mask)
		dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);

	return dma_mask;
}

static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
{
	unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);

	if (dma_mask <= DMA_BIT_MASK(24))
		gfp |= GFP_DMA;
#ifdef CONFIG_X86_64
	if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
		gfp |= GFP_DMA32;
#endif
       return gfp;
}

static inline void *
dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
		gfp_t gfp)
{
	struct dma_map_ops *ops = get_dma_ops(dev);
	void *memory;

	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);

	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
		return memory;

	if (!dev)
		dev = &x86_dma_fallback_dev;

	if (!is_device_dma_capable(dev))
		return NULL;

	if (!ops->alloc_coherent)
		return NULL;

	memory = ops->alloc_coherent(dev, size, dma_handle,
				     dma_alloc_coherent_gfp_flags(dev, gfp));
	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);

	return memory;
}

static inline void dma_free_coherent(struct device *dev, size_t size,
				     void *vaddr, dma_addr_t bus)
{
	struct dma_map_ops *ops = get_dma_ops(dev);

	WARN_ON(irqs_disabled());       /* for portability */

	if (dma_release_from_coherent(dev, get_order(size), vaddr))
		return;

	debug_dma_free_coherent(dev, size, vaddr, bus);
	if (ops->free_coherent)
		ops->free_coherent(dev, size, vaddr, bus);
}

#endif