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) 2004 IBM
3 *
4 * Implements the generic device dma API for powerpc.
5 * the pci and vio busses
6 */
7#ifndef _ASM_DMA_MAPPING_H
8#define _ASM_DMA_MAPPING_H
9#ifdef __KERNEL__
10
11#include <linux/types.h>
12#include <linux/cache.h>
13/* need struct page definitions */
14#include <linux/mm.h>
15#include <linux/scatterlist.h>
16#include <linux/dma-attrs.h>
17#include <linux/dma-debug.h>
18#include <asm/io.h>
19#include <asm/swiotlb.h>
20
21#define DMA_ERROR_CODE (~(dma_addr_t)0x0)
22
23/* Some dma direct funcs must be visible for use in other dma_ops */
24extern void *dma_direct_alloc_coherent(struct device *dev, size_t size,
25 dma_addr_t *dma_handle, gfp_t flag,
26 struct dma_attrs *attrs);
27extern void dma_direct_free_coherent(struct device *dev, size_t size,
28 void *vaddr, dma_addr_t dma_handle,
29 struct dma_attrs *attrs);
30extern int dma_direct_mmap_coherent(struct device *dev,
31 struct vm_area_struct *vma,
32 void *cpu_addr, dma_addr_t handle,
33 size_t size, struct dma_attrs *attrs);
34
35#ifdef CONFIG_NOT_COHERENT_CACHE
36/*
37 * DMA-consistent mapping functions for PowerPCs that don't support
38 * cache snooping. These allocate/free a region of uncached mapped
39 * memory space for use with DMA devices. Alternatively, you could
40 * allocate the space "normally" and use the cache management functions
41 * to ensure it is consistent.
42 */
43struct device;
44extern void *__dma_alloc_coherent(struct device *dev, size_t size,
45 dma_addr_t *handle, gfp_t gfp);
46extern void __dma_free_coherent(size_t size, void *vaddr);
47extern void __dma_sync(void *vaddr, size_t size, int direction);
48extern void __dma_sync_page(struct page *page, unsigned long offset,
49 size_t size, int direction);
50extern unsigned long __dma_get_coherent_pfn(unsigned long cpu_addr);
51
52#else /* ! CONFIG_NOT_COHERENT_CACHE */
53/*
54 * Cache coherent cores.
55 */
56
57#define __dma_alloc_coherent(dev, gfp, size, handle) NULL
58#define __dma_free_coherent(size, addr) ((void)0)
59#define __dma_sync(addr, size, rw) ((void)0)
60#define __dma_sync_page(pg, off, sz, rw) ((void)0)
61
62#endif /* ! CONFIG_NOT_COHERENT_CACHE */
63
64static inline unsigned long device_to_mask(struct device *dev)
65{
66 if (dev->dma_mask && *dev->dma_mask)
67 return *dev->dma_mask;
68 /* Assume devices without mask can take 32 bit addresses */
69 return 0xfffffffful;
70}
71
72/*
73 * Available generic sets of operations
74 */
75#ifdef CONFIG_PPC64
76extern struct dma_map_ops dma_iommu_ops;
77#endif
78extern struct dma_map_ops dma_direct_ops;
79
80static inline struct dma_map_ops *get_dma_ops(struct device *dev)
81{
82 /* We don't handle the NULL dev case for ISA for now. We could
83 * do it via an out of line call but it is not needed for now. The
84 * only ISA DMA device we support is the floppy and we have a hack
85 * in the floppy driver directly to get a device for us.
86 */
87 if (unlikely(dev == NULL))
88 return NULL;
89
90 return dev->archdata.dma_ops;
91}
92
93static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
94{
95 dev->archdata.dma_ops = ops;
96}
97
98/*
99 * get_dma_offset()
100 *
101 * Get the dma offset on configurations where the dma address can be determined
102 * from the physical address by looking at a simple offset. Direct dma and
103 * swiotlb use this function, but it is typically not used by implementations
104 * with an iommu.
105 */
106static inline dma_addr_t get_dma_offset(struct device *dev)
107{
108 if (dev)
109 return dev->archdata.dma_data.dma_offset;
110
111 return PCI_DRAM_OFFSET;
112}
113
114static inline void set_dma_offset(struct device *dev, dma_addr_t off)
115{
116 if (dev)
117 dev->archdata.dma_data.dma_offset = off;
118}
119
120/* this will be removed soon */
121#define flush_write_buffers()
122
123#include <asm-generic/dma-mapping-common.h>
124
125static inline int dma_supported(struct device *dev, u64 mask)
126{
127 struct dma_map_ops *dma_ops = get_dma_ops(dev);
128
129 if (unlikely(dma_ops == NULL))
130 return 0;
131 if (dma_ops->dma_supported == NULL)
132 return 1;
133 return dma_ops->dma_supported(dev, mask);
134}
135
136extern int dma_set_mask(struct device *dev, u64 dma_mask);
137
138#define dma_alloc_coherent(d,s,h,f) dma_alloc_attrs(d,s,h,f,NULL)
139
140static inline void *dma_alloc_attrs(struct device *dev, size_t size,
141 dma_addr_t *dma_handle, gfp_t flag,
142 struct dma_attrs *attrs)
143{
144 struct dma_map_ops *dma_ops = get_dma_ops(dev);
145 void *cpu_addr;
146
147 BUG_ON(!dma_ops);
148
149 cpu_addr = dma_ops->alloc(dev, size, dma_handle, flag, attrs);
150
151 debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
152
153 return cpu_addr;
154}
155
156#define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
157
158static inline void dma_free_attrs(struct device *dev, size_t size,
159 void *cpu_addr, dma_addr_t dma_handle,
160 struct dma_attrs *attrs)
161{
162 struct dma_map_ops *dma_ops = get_dma_ops(dev);
163
164 BUG_ON(!dma_ops);
165
166 debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
167
168 dma_ops->free(dev, size, cpu_addr, dma_handle, attrs);
169}
170
171static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
172{
173 struct dma_map_ops *dma_ops = get_dma_ops(dev);
174
175 if (dma_ops->mapping_error)
176 return dma_ops->mapping_error(dev, dma_addr);
177
178#ifdef CONFIG_PPC64
179 return (dma_addr == DMA_ERROR_CODE);
180#else
181 return 0;
182#endif
183}
184
185static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
186{
187#ifdef CONFIG_SWIOTLB
188 struct dev_archdata *sd = &dev->archdata;
189
190 if (sd->max_direct_dma_addr && addr + size > sd->max_direct_dma_addr)
191 return 0;
192#endif
193
194 if (!dev->dma_mask)
195 return 0;
196
197 return addr + size - 1 <= *dev->dma_mask;
198}
199
200static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
201{
202 return paddr + get_dma_offset(dev);
203}
204
205static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
206{
207 return daddr - get_dma_offset(dev);
208}
209
210#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
211#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
212
213#define ARCH_HAS_DMA_MMAP_COHERENT
214
215static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
216 enum dma_data_direction direction)
217{
218 BUG_ON(direction == DMA_NONE);
219 __dma_sync(vaddr, size, (int)direction);
220}
221
222#endif /* __KERNEL__ */
223#endif /* _ASM_DMA_MAPPING_H */