include/asm-powerpc/dma-mapping.h

   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 <asm/io.h>
  17
  18 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  19
  20 #ifdef CONFIG_NOT_COHERENT_CACHE
  21 /*
  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.
  27  */
  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);
  33
  34 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  35 /*
  36  * Cache coherent cores.
  37  */
  38
  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)
  43
  44 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  45
  46 #ifdef CONFIG_PPC64
  47 /*
  48  * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
  49  */
  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);
  65 };
  66
  67 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
  68 {
  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.
  73          */
  74         if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
  75                 return NULL;
  76         return dev->archdata.dma_ops;
  77 }
  78
  79 static inline int dma_supported(struct device *dev, u64 mask)
  80 {
  81         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
  82
  83         if (unlikely(dma_ops == NULL))
  84                 return 0;
  85         if (dma_ops->dma_supported == NULL)
  86                 return 1;
  87         return dma_ops->dma_supported(dev, mask);
  88 }
  89
  90 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
  91 {
  92         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
  93
  94         if (unlikely(dma_ops == NULL))
  95                 return -EIO;
  96         if (dma_ops->set_dma_mask != NULL)
  97                 return dma_ops->set_dma_mask(dev, dma_mask);
  98         if (!dev->dma_mask || !dma_supported(dev, dma_mask))
  99                 return -EIO;
 100         *dev->dma_mask = dma_mask;
 101         return 0;
 102 }
 103
 104 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 105                                        dma_addr_t *dma_handle, gfp_t flag)
 106 {
 107         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 108
 109         BUG_ON(!dma_ops);
 110         return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
 111 }
 112
 113 static inline void dma_free_coherent(struct device *dev, size_t size,
 114                                      void *cpu_addr, dma_addr_t dma_handle)
 115 {
 116         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 117
 118         BUG_ON(!dma_ops);
 119         dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
 120 }
 121
 122 static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
 123                                         size_t size,
 124                                         enum dma_data_direction direction)
 125 {
 126         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 127
 128         BUG_ON(!dma_ops);
 129         return dma_ops->map_single(dev, cpu_addr, size, direction);
 130 }
 131
 132 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 133                                     size_t size,
 134                                     enum dma_data_direction direction)
 135 {
 136         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 137
 138         BUG_ON(!dma_ops);
 139         dma_ops->unmap_single(dev, dma_addr, size, direction);
 140 }
 141
 142 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
 143                                       unsigned long offset, size_t size,
 144                                       enum dma_data_direction direction)
 145 {
 146         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 147
 148         BUG_ON(!dma_ops);
 149         return dma_ops->map_single(dev, page_address(page) + offset, size,
 150                         direction);
 151 }
 152
 153 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 154                                   size_t size,
 155                                   enum dma_data_direction direction)
 156 {
 157         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 158
 159         BUG_ON(!dma_ops);
 160         dma_ops->unmap_single(dev, dma_address, size, direction);
 161 }
 162
 163 static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
 164                              int nents, enum dma_data_direction direction)
 165 {
 166         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 167
 168         BUG_ON(!dma_ops);
 169         return dma_ops->map_sg(dev, sg, nents, direction);
 170 }
 171
 172 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 173                                 int nhwentries,
 174                                 enum dma_data_direction direction)
 175 {
 176         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 177
 178         BUG_ON(!dma_ops);
 179         dma_ops->unmap_sg(dev, sg, nhwentries, direction);
 180 }
 181
 182
 183 /*
 184  * Available generic sets of operations
 185  */
 186 extern struct dma_mapping_ops dma_iommu_ops;
 187 extern struct dma_mapping_ops dma_direct_ops;
 188
 189 extern unsigned long dma_direct_offset;
 190
 191 #else /* CONFIG_PPC64 */
 192
 193 #define dma_supported(dev, mask)        (1)
 194
 195 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
 196 {
 197         if (!dev->dma_mask || !dma_supported(dev, mask))
 198                 return -EIO;
 199
 200         *dev->dma_mask = dma_mask;
 201
 202         return 0;
 203 }
 204
 205 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 206                                        dma_addr_t * dma_handle,
 207                                        gfp_t gfp)
 208 {
 209 #ifdef CONFIG_NOT_COHERENT_CACHE
 210         return __dma_alloc_coherent(size, dma_handle, gfp);
 211 #else
 212         void *ret;
 213         /* ignore region specifiers */
 214         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
 215
 216         if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
 217                 gfp |= GFP_DMA;
 218
 219         ret = (void *)__get_free_pages(gfp, get_order(size));
 220
 221         if (ret != NULL) {
 222                 memset(ret, 0, size);
 223                 *dma_handle = virt_to_bus(ret);
 224         }
 225
 226         return ret;
 227 #endif
 228 }
 229
 230 static inline void
 231 dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 232                   dma_addr_t dma_handle)
 233 {
 234 #ifdef CONFIG_NOT_COHERENT_CACHE
 235         __dma_free_coherent(size, vaddr);
 236 #else
 237         free_pages((unsigned long)vaddr, get_order(size));
 238 #endif
 239 }
 240
 241 static inline dma_addr_t
 242 dma_map_single(struct device *dev, void *ptr, size_t size,
 243                enum dma_data_direction direction)
 244 {
 245         BUG_ON(direction == DMA_NONE);
 246
 247         __dma_sync(ptr, size, direction);
 248
 249         return virt_to_bus(ptr);
 250 }
 251
 252 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 253                                     size_t size,
 254                                     enum dma_data_direction direction)
 255 {
 256         /* We do nothing. */
 257 }
 258
 259 static inline dma_addr_t
 260 dma_map_page(struct device *dev, struct page *page,
 261              unsigned long offset, size_t size,
 262              enum dma_data_direction direction)
 263 {
 264         BUG_ON(direction == DMA_NONE);
 265
 266         __dma_sync_page(page, offset, size, direction);
 267
 268         return page_to_bus(page) + offset;
 269 }
 270
 271 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 272                                   size_t size,
 273                                   enum dma_data_direction direction)
 274 {
 275         /* We do nothing. */
 276 }
 277
 278 static inline int
 279 dma_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
 280            enum dma_data_direction direction)
 281 {
 282         struct scatterlist *sg;
 283         int i;
 284
 285         BUG_ON(direction == DMA_NONE);
 286
 287         for_each_sg(sgl, sg, nents, i) {
 288                 BUG_ON(!sg_page(sg));
 289                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 290                 sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
 291         }
 292
 293         return nents;
 294 }
 295
 296 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 297                                 int nhwentries,
 298                                 enum dma_data_direction direction)
 299 {
 300         /* We don't do anything here. */
 301 }
 302
 303 #endif /* CONFIG_PPC64 */
 304
 305 static inline void dma_sync_single_for_cpu(struct device *dev,
 306                 dma_addr_t dma_handle, size_t size,
 307                 enum dma_data_direction direction)
 308 {
 309         BUG_ON(direction == DMA_NONE);
 310         __dma_sync(bus_to_virt(dma_handle), size, direction);
 311 }
 312
 313 static inline void dma_sync_single_for_device(struct device *dev,
 314                 dma_addr_t dma_handle, size_t size,
 315                 enum dma_data_direction direction)
 316 {
 317         BUG_ON(direction == DMA_NONE);
 318         __dma_sync(bus_to_virt(dma_handle), size, direction);
 319 }
 320
 321 static inline void dma_sync_sg_for_cpu(struct device *dev,
 322                 struct scatterlist *sgl, int nents,
 323                 enum dma_data_direction direction)
 324 {
 325         struct scatterlist *sg;
 326         int i;
 327
 328         BUG_ON(direction == DMA_NONE);
 329
 330         for_each_sg(sgl, sg, nents, i)
 331                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 332 }
 333
 334 static inline void dma_sync_sg_for_device(struct device *dev,
 335                 struct scatterlist *sgl, int nents,
 336                 enum dma_data_direction direction)
 337 {
 338         struct scatterlist *sg;
 339         int i;
 340
 341         BUG_ON(direction == DMA_NONE);
 342
 343         for_each_sg(sgl, sg, nents, i)
 344                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 345 }
 346
 347 static inline int dma_mapping_error(dma_addr_t dma_addr)
 348 {
 349 #ifdef CONFIG_PPC64
 350         return (dma_addr == DMA_ERROR_CODE);
 351 #else
 352         return 0;
 353 #endif
 354 }
 355
 356 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 357 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 358 #ifdef CONFIG_NOT_COHERENT_CACHE
 359 #define dma_is_consistent(d, h) (0)
 360 #else
 361 #define dma_is_consistent(d, h) (1)
 362 #endif
 363
 364 static inline int dma_get_cache_alignment(void)
 365 {
 366 #ifdef CONFIG_PPC64
 367         /* no easy way to get cache size on all processors, so return
 368          * the maximum possible, to be safe */
 369         return (1 << INTERNODE_CACHE_SHIFT);
 370 #else
 371         /*
 372          * Each processor family will define its own L1_CACHE_SHIFT,
 373          * L1_CACHE_BYTES wraps to this, so this is always safe.
 374          */
 375         return L1_CACHE_BYTES;
 376 #endif
 377 }
 378
 379 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 380                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 381                 enum dma_data_direction direction)
 382 {
 383         /* just sync everything for now */
 384         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 385 }
 386
 387 static inline void dma_sync_single_range_for_device(struct device *dev,
 388                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 389                 enum dma_data_direction direction)
 390 {
 391         /* just sync everything for now */
 392         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 393 }
 394
 395 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 396                 enum dma_data_direction direction)
 397 {
 398         BUG_ON(direction == DMA_NONE);
 399         __dma_sync(vaddr, size, (int)direction);
 400 }
 401
 402 #endif /* __KERNEL__ */
 403 #endif  /* _ASM_DMA_MAPPING_H */