2 * Copyright (C) 2004 IBM
4 * Implements the generic device dma API for powerpc.
5 * the pci and vio busses
7 #ifndef _ASM_DMA_MAPPING_H
8 #define _ASM_DMA_MAPPING_H
11 #include <linux/types.h>
12 #include <linux/cache.h>
13 /* need struct page definitions */
15 #include <linux/scatterlist.h>
18 #define DMA_ERROR_CODE (~(dma_addr_t)0x0)
20 #ifdef CONFIG_NOT_COHERENT_CACHE
22 * DMA-consistent mapping functions for PowerPCs that don't support
23 * cache snooping. These allocate/free a region of uncached mapped
24 * memory space for use with DMA devices. Alternatively, you could
25 * allocate the space "normally" and use the cache management functions
26 * to ensure it is consistent.
28 extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp);
29 extern void __dma_free_coherent(size_t size, void *vaddr);
30 extern void __dma_sync(void *vaddr, size_t size, int direction);
31 extern void __dma_sync_page(struct page *page, unsigned long offset,
32 size_t size, int direction);
34 #else /* ! CONFIG_NOT_COHERENT_CACHE */
36 * Cache coherent cores.
39 #define __dma_alloc_coherent(gfp, size, handle) NULL
40 #define __dma_free_coherent(size, addr) ((void)0)
41 #define __dma_sync(addr, size, rw) ((void)0)
42 #define __dma_sync_page(pg, off, sz, rw) ((void)0)
44 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
48 * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
50 struct dma_mapping_ops {
51 void * (*alloc_coherent)(struct device *dev, size_t size,
52 dma_addr_t *dma_handle, gfp_t flag);
53 void (*free_coherent)(struct device *dev, size_t size,
54 void *vaddr, dma_addr_t dma_handle);
55 dma_addr_t (*map_single)(struct device *dev, void *ptr,
56 size_t size, enum dma_data_direction direction);
57 void (*unmap_single)(struct device *dev, dma_addr_t dma_addr,
58 size_t size, enum dma_data_direction direction);
59 int (*map_sg)(struct device *dev, struct scatterlist *sg,
60 int nents, enum dma_data_direction direction);
61 void (*unmap_sg)(struct device *dev, struct scatterlist *sg,
62 int nents, enum dma_data_direction direction);
63 int (*dma_supported)(struct device *dev, u64 mask);
64 int (*set_dma_mask)(struct device *dev, u64 dma_mask);
67 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
69 /* We don't handle the NULL dev case for ISA for now. We could
70 * do it via an out of line call but it is not needed for now. The
71 * only ISA DMA device we support is the floppy and we have a hack
72 * in the floppy driver directly to get a device for us.
74 if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
76 return dev->archdata.dma_ops;
79 static inline int dma_supported(struct device *dev, u64 mask)
81 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
83 if (unlikely(dma_ops == NULL))
85 if (dma_ops->dma_supported == NULL)
87 return dma_ops->dma_supported(dev, mask);
90 /* We have our own implementation of pci_set_dma_mask() */
91 #define HAVE_ARCH_PCI_SET_DMA_MASK
93 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
95 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
97 if (unlikely(dma_ops == NULL))
99 if (dma_ops->set_dma_mask != NULL)
100 return dma_ops->set_dma_mask(dev, dma_mask);
101 if (!dev->dma_mask || !dma_supported(dev, dma_mask))
103 *dev->dma_mask = dma_mask;
107 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
108 dma_addr_t *dma_handle, gfp_t flag)
110 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
113 return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
116 static inline void dma_free_coherent(struct device *dev, size_t size,
117 void *cpu_addr, dma_addr_t dma_handle)
119 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
122 dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
125 static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
127 enum dma_data_direction direction)
129 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
132 return dma_ops->map_single(dev, cpu_addr, size, direction);
135 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
137 enum dma_data_direction direction)
139 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
142 dma_ops->unmap_single(dev, dma_addr, size, direction);
145 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
146 unsigned long offset, size_t size,
147 enum dma_data_direction direction)
149 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
152 return dma_ops->map_single(dev, page_address(page) + offset, size,
156 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
158 enum dma_data_direction direction)
160 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
163 dma_ops->unmap_single(dev, dma_address, size, direction);
166 static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
167 int nents, enum dma_data_direction direction)
169 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
172 return dma_ops->map_sg(dev, sg, nents, direction);
175 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
177 enum dma_data_direction direction)
179 struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
182 dma_ops->unmap_sg(dev, sg, nhwentries, direction);
187 * Available generic sets of operations
189 extern struct dma_mapping_ops dma_iommu_ops;
190 extern struct dma_mapping_ops dma_direct_ops;
192 extern unsigned long dma_direct_offset;
194 #else /* CONFIG_PPC64 */
196 #define dma_supported(dev, mask) (1)
198 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
200 if (!dev->dma_mask || !dma_supported(dev, mask))
203 *dev->dma_mask = dma_mask;
208 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
209 dma_addr_t * dma_handle,
212 #ifdef CONFIG_NOT_COHERENT_CACHE
213 return __dma_alloc_coherent(size, dma_handle, gfp);
216 /* ignore region specifiers */
217 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
219 if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
222 ret = (void *)__get_free_pages(gfp, get_order(size));
225 memset(ret, 0, size);
226 *dma_handle = virt_to_bus(ret);
234 dma_free_coherent(struct device *dev, size_t size, void *vaddr,
235 dma_addr_t dma_handle)
237 #ifdef CONFIG_NOT_COHERENT_CACHE
238 __dma_free_coherent(size, vaddr);
240 free_pages((unsigned long)vaddr, get_order(size));
244 static inline dma_addr_t
245 dma_map_single(struct device *dev, void *ptr, size_t size,
246 enum dma_data_direction direction)
248 BUG_ON(direction == DMA_NONE);
250 __dma_sync(ptr, size, direction);
252 return virt_to_bus(ptr);
255 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
257 enum dma_data_direction direction)
262 static inline dma_addr_t
263 dma_map_page(struct device *dev, struct page *page,
264 unsigned long offset, size_t size,
265 enum dma_data_direction direction)
267 BUG_ON(direction == DMA_NONE);
269 __dma_sync_page(page, offset, size, direction);
271 return page_to_bus(page) + offset;
274 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
276 enum dma_data_direction direction)
282 dma_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
283 enum dma_data_direction direction)
285 struct scatterlist *sg;
288 BUG_ON(direction == DMA_NONE);
290 for_each_sg(sgl, sg, nents, i) {
291 BUG_ON(!sg_page(sg));
292 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
293 sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
299 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
301 enum dma_data_direction direction)
303 /* We don't do anything here. */
306 #endif /* CONFIG_PPC64 */
308 static inline void dma_sync_single_for_cpu(struct device *dev,
309 dma_addr_t dma_handle, size_t size,
310 enum dma_data_direction direction)
312 BUG_ON(direction == DMA_NONE);
313 __dma_sync(bus_to_virt(dma_handle), size, direction);
316 static inline void dma_sync_single_for_device(struct device *dev,
317 dma_addr_t dma_handle, size_t size,
318 enum dma_data_direction direction)
320 BUG_ON(direction == DMA_NONE);
321 __dma_sync(bus_to_virt(dma_handle), size, direction);
324 static inline void dma_sync_sg_for_cpu(struct device *dev,
325 struct scatterlist *sgl, int nents,
326 enum dma_data_direction direction)
328 struct scatterlist *sg;
331 BUG_ON(direction == DMA_NONE);
333 for_each_sg(sgl, sg, nents, i)
334 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
337 static inline void dma_sync_sg_for_device(struct device *dev,
338 struct scatterlist *sgl, int nents,
339 enum dma_data_direction direction)
341 struct scatterlist *sg;
344 BUG_ON(direction == DMA_NONE);
346 for_each_sg(sgl, sg, nents, i)
347 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
350 static inline int dma_mapping_error(dma_addr_t dma_addr)
353 return (dma_addr == DMA_ERROR_CODE);
359 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
360 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
361 #ifdef CONFIG_NOT_COHERENT_CACHE
362 #define dma_is_consistent(d, h) (0)
364 #define dma_is_consistent(d, h) (1)
367 static inline int dma_get_cache_alignment(void)
370 /* no easy way to get cache size on all processors, so return
371 * the maximum possible, to be safe */
372 return (1 << INTERNODE_CACHE_SHIFT);
375 * Each processor family will define its own L1_CACHE_SHIFT,
376 * L1_CACHE_BYTES wraps to this, so this is always safe.
378 return L1_CACHE_BYTES;
382 static inline void dma_sync_single_range_for_cpu(struct device *dev,
383 dma_addr_t dma_handle, unsigned long offset, size_t size,
384 enum dma_data_direction direction)
386 /* just sync everything for now */
387 dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
390 static inline void dma_sync_single_range_for_device(struct device *dev,
391 dma_addr_t dma_handle, unsigned long offset, size_t size,
392 enum dma_data_direction direction)
394 /* just sync everything for now */
395 dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
398 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
399 enum dma_data_direction direction)
401 BUG_ON(direction == DMA_NONE);
402 __dma_sync(vaddr, size, (int)direction);
405 #endif /* __KERNEL__ */
406 #endif /* _ASM_DMA_MAPPING_H */