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 <asm/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 /* We do nothing. */
 253 #define dma_unmap_single(dev, addr, size, dir)  ((void)0)
 254
 255 static inline dma_addr_t
 256 dma_map_page(struct device *dev, struct page *page,
 257              unsigned long offset, size_t size,
 258              enum dma_data_direction direction)
 259 {
 260         BUG_ON(direction == DMA_NONE);
 261
 262         __dma_sync_page(page, offset, size, direction);
 263
 264         return page_to_bus(page) + offset;
 265 }
 266
 267 /* We do nothing. */
 268 #define dma_unmap_page(dev, handle, size, dir)  ((void)0)
 269
 270 static inline int
 271 dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
 272            enum dma_data_direction direction)
 273 {
 274         int i;
 275
 276         BUG_ON(direction == DMA_NONE);
 277
 278         for (i = 0; i < nents; i++, sg++) {
 279                 BUG_ON(!sg->page);
 280                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 281                 sg->dma_address = page_to_bus(sg->page) + sg->offset;
 282         }
 283
 284         return nents;
 285 }
 286
 287 /* We don't do anything here. */
 288 #define dma_unmap_sg(dev, sg, nents, dir)       ((void)0)
 289
 290 #endif /* CONFIG_PPC64 */
 291
 292 static inline void dma_sync_single_for_cpu(struct device *dev,
 293                 dma_addr_t dma_handle, size_t size,
 294                 enum dma_data_direction direction)
 295 {
 296         BUG_ON(direction == DMA_NONE);
 297         __dma_sync(bus_to_virt(dma_handle), size, direction);
 298 }
 299
 300 static inline void dma_sync_single_for_device(struct device *dev,
 301                 dma_addr_t dma_handle, size_t size,
 302                 enum dma_data_direction direction)
 303 {
 304         BUG_ON(direction == DMA_NONE);
 305         __dma_sync(bus_to_virt(dma_handle), size, direction);
 306 }
 307
 308 static inline void dma_sync_sg_for_cpu(struct device *dev,
 309                 struct scatterlist *sg, int nents,
 310                 enum dma_data_direction direction)
 311 {
 312         int i;
 313
 314         BUG_ON(direction == DMA_NONE);
 315
 316         for (i = 0; i < nents; i++, sg++)
 317                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 318 }
 319
 320 static inline void dma_sync_sg_for_device(struct device *dev,
 321                 struct scatterlist *sg, int nents,
 322                 enum dma_data_direction direction)
 323 {
 324         int i;
 325
 326         BUG_ON(direction == DMA_NONE);
 327
 328         for (i = 0; i < nents; i++, sg++)
 329                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 330 }
 331
 332 static inline int dma_mapping_error(dma_addr_t dma_addr)
 333 {
 334 #ifdef CONFIG_PPC64
 335         return (dma_addr == DMA_ERROR_CODE);
 336 #else
 337         return 0;
 338 #endif
 339 }
 340
 341 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 342 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 343 #ifdef CONFIG_NOT_COHERENT_CACHE
 344 #define dma_is_consistent(d, h) (0)
 345 #else
 346 #define dma_is_consistent(d, h) (1)
 347 #endif
 348
 349 static inline int dma_get_cache_alignment(void)
 350 {
 351 #ifdef CONFIG_PPC64
 352         /* no easy way to get cache size on all processors, so return
 353          * the maximum possible, to be safe */
 354         return (1 << INTERNODE_CACHE_SHIFT);
 355 #else
 356         /*
 357          * Each processor family will define its own L1_CACHE_SHIFT,
 358          * L1_CACHE_BYTES wraps to this, so this is always safe.
 359          */
 360         return L1_CACHE_BYTES;
 361 #endif
 362 }
 363
 364 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 365                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 366                 enum dma_data_direction direction)
 367 {
 368         /* just sync everything for now */
 369         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 370 }
 371
 372 static inline void dma_sync_single_range_for_device(struct device *dev,
 373                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 374                 enum dma_data_direction direction)
 375 {
 376         /* just sync everything for now */
 377         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 378 }
 379
 380 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 381                 enum dma_data_direction direction)
 382 {
 383         BUG_ON(direction == DMA_NONE);
 384         __dma_sync(vaddr, size, (int)direction);
 385 }
 386
 387 #endif /* __KERNEL__ */
 388 #endif  /* _ASM_DMA_MAPPING_H */