1#ifndef _ASM_X86_DMA_MAPPING_H
2#define _ASM_X86_DMA_MAPPING_H
3
4/*
5 * IOMMU interface. See Documentation/DMA-API-HOWTO.txt and
6 * Documentation/DMA-API.txt for documentation.
7 */
8
9#include <linux/kmemcheck.h>
10#include <linux/scatterlist.h>
11#include <linux/dma-debug.h>
12#include <linux/dma-attrs.h>
13#include <asm/io.h>
14#include <asm/swiotlb.h>
15#include <asm-generic/dma-coherent.h>
16#include <linux/dma-contiguous.h>
17
18#ifdef CONFIG_ISA
19# define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
20#else
21# define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
22#endif
23
24#define DMA_ERROR_CODE	0
25
26extern int iommu_merge;
27extern struct device x86_dma_fallback_dev;
28extern int panic_on_overflow;
29
30extern struct dma_map_ops *dma_ops;
31
32static inline struct dma_map_ops *get_dma_ops(struct device *dev)
33{
34#ifndef CONFIG_X86_DEV_DMA_OPS
35	return dma_ops;
36#else
37	if (unlikely(!dev) || !dev->archdata.dma_ops)
38		return dma_ops;
39	else
40		return dev->archdata.dma_ops;
41#endif
42}
43
44#include <asm-generic/dma-mapping-common.h>
45
46/* Make sure we keep the same behaviour */
47static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
48{
49	struct dma_map_ops *ops = get_dma_ops(dev);
50	debug_dma_mapping_error(dev, dma_addr);
51	if (ops->mapping_error)
52		return ops->mapping_error(dev, dma_addr);
53
54	return (dma_addr == DMA_ERROR_CODE);
55}
56
57#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
58#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
59
60extern int dma_supported(struct device *hwdev, u64 mask);
61extern int dma_set_mask(struct device *dev, u64 mask);
62
63extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
64					dma_addr_t *dma_addr, gfp_t flag,
65					struct dma_attrs *attrs);
66
67extern void dma_generic_free_coherent(struct device *dev, size_t size,
68				      void *vaddr, dma_addr_t dma_addr,
69				      struct dma_attrs *attrs);
70
71#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
72extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
73extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
74extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
75#else
76
77static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
78{
79	if (!dev->dma_mask)
80		return 0;
81
82	return addr + size - 1 <= *dev->dma_mask;
83}
84
85static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
86{
87	return paddr;
88}
89
90static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
91{
92	return daddr;
93}
94#endif /* CONFIG_X86_DMA_REMAP */
95
96static inline void
97dma_cache_sync(struct device *dev, void *vaddr, size_t size,
98	enum dma_data_direction dir)
99{
100	flush_write_buffers();
101}
102
103static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
104						    gfp_t gfp)
105{
106	unsigned long dma_mask = 0;
107
108	dma_mask = dev->coherent_dma_mask;
109	if (!dma_mask)
110		dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
111
112	return dma_mask;
113}
114
115static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
116{
117	unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
118
119	if (dma_mask <= DMA_BIT_MASK(24))
120		gfp |= GFP_DMA;
121#ifdef CONFIG_X86_64
122	if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
123		gfp |= GFP_DMA32;
124#endif
125       return gfp;
126}
127
128#define dma_alloc_coherent(d,s,h,f)	dma_alloc_attrs(d,s,h,f,NULL)
129
130static inline void *
131dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
132		gfp_t gfp, struct dma_attrs *attrs)
133{
134	struct dma_map_ops *ops = get_dma_ops(dev);
135	void *memory;
136
137	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
138
139	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
140		return memory;
141
142	if (!dev)
143		dev = &x86_dma_fallback_dev;
144
145	if (!is_device_dma_capable(dev))
146		return NULL;
147
148	if (!ops->alloc)
149		return NULL;
150
151	memory = ops->alloc(dev, size, dma_handle,
152			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
153	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
154
155	return memory;
156}
157
158#define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
159
160static inline void dma_free_attrs(struct device *dev, size_t size,
161				  void *vaddr, dma_addr_t bus,
162				  struct dma_attrs *attrs)
163{
164	struct dma_map_ops *ops = get_dma_ops(dev);
165
166	WARN_ON(irqs_disabled());       /* for portability */
167
168	if (dma_release_from_coherent(dev, get_order(size), vaddr))
169		return;
170
171	debug_dma_free_coherent(dev, size, vaddr, bus);
172	if (ops->free)
173		ops->free(dev, size, vaddr, bus, attrs);
174}
175
176#endif
177