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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef ASMARM_DMA_MAPPING_H
#define ASMARM_DMA_MAPPING_H
#ifdef __KERNEL__
#include <linux/mm_types.h>
#include <linux/scatterlist.h>
#include <linux/dma-debug.h>
#include <asm/memory.h>
#include <xen/xen.h>
#include <asm/xen/hypervisor.h>
extern const struct dma_map_ops arm_dma_ops;
extern const struct dma_map_ops arm_coherent_dma_ops;
static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
{
if (IS_ENABLED(CONFIG_MMU) && !IS_ENABLED(CONFIG_ARM_LPAE))
return &arm_dma_ops;
return NULL;
}
#ifdef __arch_page_to_dma
#error Please update to __arch_pfn_to_dma
#endif
/*
* dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
* functions used internally by the DMA-mapping API to provide DMA
* addresses. They must not be used by drivers.
*/
#ifndef __arch_pfn_to_dma
static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
{
if (dev)
pfn -= dev->dma_pfn_offset;
return (dma_addr_t)__pfn_to_bus(pfn);
}
static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
{
unsigned long pfn = __bus_to_pfn(addr);
if (dev)
pfn += dev->dma_pfn_offset;
return pfn;
}
static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
{
if (dev) {
unsigned long pfn = dma_to_pfn(dev, addr);
return phys_to_virt(__pfn_to_phys(pfn));
}
return (void *)__bus_to_virt((unsigned long)addr);
}
static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
{
if (dev)
return pfn_to_dma(dev, virt_to_pfn(addr));
return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
}
#else
static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
{
return __arch_pfn_to_dma(dev, pfn);
}
static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
{
return __arch_dma_to_pfn(dev, addr);
}
static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
{
return __arch_dma_to_virt(dev, addr);
}
static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
{
return __arch_virt_to_dma(dev, addr);
}
#endif
/**
* arm_dma_alloc - allocate consistent memory for DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @size: required memory size
* @handle: bus-specific DMA address
* @attrs: optinal attributes that specific mapping properties
*
* Allocate some memory for a device for performing DMA. This function
* allocates pages, and will return the CPU-viewed address, and sets @handle
* to be the device-viewed address.
*/
extern void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
gfp_t gfp, unsigned long attrs);
/**
* arm_dma_free - free memory allocated by arm_dma_alloc
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @size: size of memory originally requested in dma_alloc_coherent
* @cpu_addr: CPU-view address returned from dma_alloc_coherent
* @handle: device-view address returned from dma_alloc_coherent
* @attrs: optinal attributes that specific mapping properties
*
* Free (and unmap) a DMA buffer previously allocated by
* arm_dma_alloc().
*
* References to memory and mappings associated with cpu_addr/handle
* during and after this call executing are illegal.
*/
extern void arm_dma_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t handle, unsigned long attrs);
/**
* arm_dma_mmap - map a coherent DMA allocation into user space
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @vma: vm_area_struct describing requested user mapping
* @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
* @handle: device-view address returned from dma_alloc_coherent
* @size: size of memory originally requested in dma_alloc_coherent
* @attrs: optinal attributes that specific mapping properties
*
* Map a coherent DMA buffer previously allocated by dma_alloc_coherent
* into user space. The coherent DMA buffer must not be freed by the
* driver until the user space mapping has been released.
*/
extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
unsigned long attrs);
/*
* For SA-1111, IXP425, and ADI systems the dma-mapping functions are "magic"
* and utilize bounce buffers as needed to work around limited DMA windows.
*
* On the SA-1111, a bug limits DMA to only certain regions of RAM.
* On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
* On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
*
* The following are helper functions used by the dmabounce subystem
*
*/
/**
* dmabounce_register_dev
*
* @dev: valid struct device pointer
* @small_buf_size: size of buffers to use with small buffer pool
* @large_buf_size: size of buffers to use with large buffer pool (can be 0)
* @needs_bounce_fn: called to determine whether buffer needs bouncing
*
* This function should be called by low-level platform code to register
* a device as requireing DMA buffer bouncing. The function will allocate
* appropriate DMA pools for the device.
*/
extern int dmabounce_register_dev(struct device *, unsigned long,
unsigned long, int (*)(struct device *, dma_addr_t, size_t));
/**
* dmabounce_unregister_dev
*
* @dev: valid struct device pointer
*
* This function should be called by low-level platform code when device
* that was previously registered with dmabounce_register_dev is removed
* from the system.
*
*/
extern void dmabounce_unregister_dev(struct device *);
/*
* The scatter list versions of the above methods.
*/
extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction, unsigned long attrs);
extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
enum dma_data_direction, unsigned long attrs);
extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
enum dma_data_direction);
extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
enum dma_data_direction);
extern int arm_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
unsigned long attrs);
#endif /* __KERNEL__ */
#endif
|
