arch/powerpc/include/asm/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 <linux/dma-attrs.h>
  17 #include <asm/io.h>
  18
  19 #define DMA_ERROR_CODE          (~(dma_addr_t)0x0)
  20
  21 #ifdef CONFIG_NOT_COHERENT_CACHE
  22 /*
  23  * DMA-consistent mapping functions for PowerPCs that don't support
  24  * cache snooping.  These allocate/free a region of uncached mapped
  25  * memory space for use with DMA devices.  Alternatively, you could
  26  * allocate the space "normally" and use the cache management functions
  27  * to ensure it is consistent.
  28  */
  29 extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp);
  30 extern void __dma_free_coherent(size_t size, void *vaddr);
  31 extern void __dma_sync(void *vaddr, size_t size, int direction);
  32 extern void __dma_sync_page(struct page *page, unsigned long offset,
  33                                  size_t size, int direction);
  34
  35 #else /* ! CONFIG_NOT_COHERENT_CACHE */
  36 /*
  37  * Cache coherent cores.
  38  */
  39
  40 #define __dma_alloc_coherent(gfp, size, handle) NULL
  41 #define __dma_free_coherent(size, addr)         ((void)0)
  42 #define __dma_sync(addr, size, rw)              ((void)0)
  43 #define __dma_sync_page(pg, off, sz, rw)        ((void)0)
  44
  45 #endif /* ! CONFIG_NOT_COHERENT_CACHE */
  46
  47 static inline unsigned long device_to_mask(struct device *dev)
  48 {
  49         if (dev->dma_mask && *dev->dma_mask)
  50                 return *dev->dma_mask;
  51         /* Assume devices without mask can take 32 bit addresses */
  52         return 0xfffffffful;
  53 }
  54
  55 /*
  56  * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
  57  */
  58 struct dma_mapping_ops {
  59         void *          (*alloc_coherent)(struct device *dev, size_t size,
  60                                 dma_addr_t *dma_handle, gfp_t flag);
  61         void            (*free_coherent)(struct device *dev, size_t size,
  62                                 void *vaddr, dma_addr_t dma_handle);
  63         dma_addr_t      (*map_single)(struct device *dev, void *ptr,
  64                                 size_t size, enum dma_data_direction direction,
  65                                 struct dma_attrs *attrs);
  66         void            (*unmap_single)(struct device *dev, dma_addr_t dma_addr,
  67                                 size_t size, enum dma_data_direction direction,
  68                                 struct dma_attrs *attrs);
  69         int             (*map_sg)(struct device *dev, struct scatterlist *sg,
  70                                 int nents, enum dma_data_direction direction,
  71                                 struct dma_attrs *attrs);
  72         void            (*unmap_sg)(struct device *dev, struct scatterlist *sg,
  73                                 int nents, enum dma_data_direction direction,
  74                                 struct dma_attrs *attrs);
  75         int             (*dma_supported)(struct device *dev, u64 mask);
  76         int             (*set_dma_mask)(struct device *dev, u64 dma_mask);
  77         dma_addr_t      (*map_page)(struct device *dev, struct page *page,
  78                                 unsigned long offset, size_t size,
  79                                 enum dma_data_direction direction,
  80                                 struct dma_attrs *attrs);
  81         void            (*unmap_page)(struct device *dev,
  82                                 dma_addr_t dma_address, size_t size,
  83                                 enum dma_data_direction direction,
  84                                 struct dma_attrs *attrs);
  85 };
  86
  87 /*
  88  * Available generic sets of operations
  89  */
  90 #ifdef CONFIG_PPC64
  91 extern struct dma_mapping_ops dma_iommu_ops;
  92 #endif
  93 extern struct dma_mapping_ops dma_direct_ops;
  94
  95 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
  96 {
  97         /* We don't handle the NULL dev case for ISA for now. We could
  98          * do it via an out of line call but it is not needed for now. The
  99          * only ISA DMA device we support is the floppy and we have a hack
 100          * in the floppy driver directly to get a device for us.
 101          */
 102
 103         if (unlikely(dev == NULL) || dev->archdata.dma_ops == NULL) {
 104 #ifdef CONFIG_PPC64
 105                 return NULL;
 106 #else
 107                 /* Use default on 32-bit if dma_ops is not set up */
 108                 /* TODO: Long term, we should fix drivers so that dev and
 109                  * archdata dma_ops are set up for all buses.
 110                  */
 111                 return &dma_direct_ops;
 112 #endif
 113         }
 114
 115         return dev->archdata.dma_ops;
 116 }
 117
 118 static inline void set_dma_ops(struct device *dev, struct dma_mapping_ops *ops)
 119 {
 120         dev->archdata.dma_ops = ops;
 121 }
 122
 123 static inline int dma_supported(struct device *dev, u64 mask)
 124 {
 125         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 126
 127         if (unlikely(dma_ops == NULL))
 128                 return 0;
 129         if (dma_ops->dma_supported == NULL)
 130                 return 1;
 131         return dma_ops->dma_supported(dev, mask);
 132 }
 133
 134 /* We have our own implementation of pci_set_dma_mask() */
 135 #define HAVE_ARCH_PCI_SET_DMA_MASK
 136
 137 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
 138 {
 139         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 140
 141         if (unlikely(dma_ops == NULL))
 142                 return -EIO;
 143         if (dma_ops->set_dma_mask != NULL)
 144                 return dma_ops->set_dma_mask(dev, dma_mask);
 145         if (!dev->dma_mask || !dma_supported(dev, dma_mask))
 146                 return -EIO;
 147         *dev->dma_mask = dma_mask;
 148         return 0;
 149 }
 150
 151 /*
 152  * TODO: map_/unmap_single will ideally go away, to be completely
 153  * replaced by map/unmap_page.   Until then, we allow dma_ops to have
 154  * one or the other, or both by checking to see if the specific
 155  * function requested exists; and if not, falling back on the other set.
 156  */
 157 static inline dma_addr_t dma_map_single_attrs(struct device *dev,
 158                                               void *cpu_addr,
 159                                               size_t size,
 160                                               enum dma_data_direction direction,
 161                                               struct dma_attrs *attrs)
 162 {
 163         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 164
 165         BUG_ON(!dma_ops);
 166
 167         if (dma_ops->map_single)
 168                 return dma_ops->map_single(dev, cpu_addr, size, direction,
 169                                            attrs);
 170
 171         return dma_ops->map_page(dev, virt_to_page(cpu_addr),
 172                                  (unsigned long)cpu_addr % PAGE_SIZE, size,
 173                                  direction, attrs);
 174 }
 175
 176 static inline void dma_unmap_single_attrs(struct device *dev,
 177                                           dma_addr_t dma_addr,
 178                                           size_t size,
 179                                           enum dma_data_direction direction,
 180                                           struct dma_attrs *attrs)
 181 {
 182         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 183
 184         BUG_ON(!dma_ops);
 185
 186         if (dma_ops->unmap_single) {
 187                 dma_ops->unmap_single(dev, dma_addr, size, direction, attrs);
 188                 return;
 189         }
 190
 191         dma_ops->unmap_page(dev, dma_addr, size, direction, attrs);
 192 }
 193
 194 static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 195                                             struct page *page,
 196                                             unsigned long offset, size_t size,
 197                                             enum dma_data_direction direction,
 198                                             struct dma_attrs *attrs)
 199 {
 200         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 201
 202         BUG_ON(!dma_ops);
 203
 204         if (dma_ops->map_page)
 205                 return dma_ops->map_page(dev, page, offset, size, direction,
 206                                          attrs);
 207
 208         return dma_ops->map_single(dev, page_address(page) + offset, size,
 209                                    direction, attrs);
 210 }
 211
 212 static inline void dma_unmap_page_attrs(struct device *dev,
 213                                         dma_addr_t dma_address,
 214                                         size_t size,
 215                                         enum dma_data_direction direction,
 216                                         struct dma_attrs *attrs)
 217 {
 218         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 219
 220         BUG_ON(!dma_ops);
 221
 222         if (dma_ops->unmap_page) {
 223                 dma_ops->unmap_page(dev, dma_address, size, direction, attrs);
 224                 return;
 225         }
 226
 227         dma_ops->unmap_single(dev, dma_address, size, direction, attrs);
 228 }
 229
 230 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 231                                    int nents, enum dma_data_direction direction,
 232                                    struct dma_attrs *attrs)
 233 {
 234         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 235
 236         BUG_ON(!dma_ops);
 237         return dma_ops->map_sg(dev, sg, nents, direction, attrs);
 238 }
 239
 240 static inline void dma_unmap_sg_attrs(struct device *dev,
 241                                       struct scatterlist *sg,
 242                                       int nhwentries,
 243                                       enum dma_data_direction direction,
 244                                       struct dma_attrs *attrs)
 245 {
 246         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 247
 248         BUG_ON(!dma_ops);
 249         dma_ops->unmap_sg(dev, sg, nhwentries, direction, attrs);
 250 }
 251
 252 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 253                                        dma_addr_t *dma_handle, gfp_t flag)
 254 {
 255         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 256
 257         BUG_ON(!dma_ops);
 258         return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
 259 }
 260
 261 static inline void dma_free_coherent(struct device *dev, size_t size,
 262                                      void *cpu_addr, dma_addr_t dma_handle)
 263 {
 264         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 265
 266         BUG_ON(!dma_ops);
 267         dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
 268 }
 269
 270 static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
 271                                         size_t size,
 272                                         enum dma_data_direction direction)
 273 {
 274         return dma_map_single_attrs(dev, cpu_addr, size, direction, NULL);
 275 }
 276
 277 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 278                                     size_t size,
 279                                     enum dma_data_direction direction)
 280 {
 281         dma_unmap_single_attrs(dev, dma_addr, size, direction, NULL);
 282 }
 283
 284 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
 285                                       unsigned long offset, size_t size,
 286                                       enum dma_data_direction direction)
 287 {
 288         return dma_map_page_attrs(dev, page, offset, size, direction, NULL);
 289 }
 290
 291 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 292                                   size_t size,
 293                                   enum dma_data_direction direction)
 294 {
 295         dma_unmap_page_attrs(dev, dma_address, size, direction, NULL);
 296 }
 297
 298 static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
 299                              int nents, enum dma_data_direction direction)
 300 {
 301         return dma_map_sg_attrs(dev, sg, nents, direction, NULL);
 302 }
 303
 304 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 305                                 int nhwentries,
 306                                 enum dma_data_direction direction)
 307 {
 308         dma_unmap_sg_attrs(dev, sg, nhwentries, direction, NULL);
 309 }
 310
 311 static inline void dma_sync_single_for_cpu(struct device *dev,
 312                 dma_addr_t dma_handle, size_t size,
 313                 enum dma_data_direction direction)
 314 {
 315         BUG_ON(direction == DMA_NONE);
 316         __dma_sync(bus_to_virt(dma_handle), size, direction);
 317 }
 318
 319 static inline void dma_sync_single_for_device(struct device *dev,
 320                 dma_addr_t dma_handle, size_t size,
 321                 enum dma_data_direction direction)
 322 {
 323         BUG_ON(direction == DMA_NONE);
 324         __dma_sync(bus_to_virt(dma_handle), size, direction);
 325 }
 326
 327 static inline void dma_sync_sg_for_cpu(struct device *dev,
 328                 struct scatterlist *sgl, int nents,
 329                 enum dma_data_direction direction)
 330 {
 331         struct scatterlist *sg;
 332         int i;
 333
 334         BUG_ON(direction == DMA_NONE);
 335
 336         for_each_sg(sgl, sg, nents, i)
 337                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 338 }
 339
 340 static inline void dma_sync_sg_for_device(struct device *dev,
 341                 struct scatterlist *sgl, int nents,
 342                 enum dma_data_direction direction)
 343 {
 344         struct scatterlist *sg;
 345         int i;
 346
 347         BUG_ON(direction == DMA_NONE);
 348
 349         for_each_sg(sgl, sg, nents, i)
 350                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
 351 }
 352
 353 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 354 {
 355 #ifdef CONFIG_PPC64
 356         return (dma_addr == DMA_ERROR_CODE);
 357 #else
 358         return 0;
 359 #endif
 360 }
 361
 362 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 363 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 364 #ifdef CONFIG_NOT_COHERENT_CACHE
 365 #define dma_is_consistent(d, h) (0)
 366 #else
 367 #define dma_is_consistent(d, h) (1)
 368 #endif
 369
 370 static inline int dma_get_cache_alignment(void)
 371 {
 372 #ifdef CONFIG_PPC64
 373         /* no easy way to get cache size on all processors, so return
 374          * the maximum possible, to be safe */
 375         return (1 << INTERNODE_CACHE_SHIFT);
 376 #else
 377         /*
 378          * Each processor family will define its own L1_CACHE_SHIFT,
 379          * L1_CACHE_BYTES wraps to this, so this is always safe.
 380          */
 381         return L1_CACHE_BYTES;
 382 #endif
 383 }
 384
 385 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 386                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 387                 enum dma_data_direction direction)
 388 {
 389         /* just sync everything for now */
 390         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 391 }
 392
 393 static inline void dma_sync_single_range_for_device(struct device *dev,
 394                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 395                 enum dma_data_direction direction)
 396 {
 397         /* just sync everything for now */
 398         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 399 }
 400
 401 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 402                 enum dma_data_direction direction)
 403 {
 404         BUG_ON(direction == DMA_NONE);
 405         __dma_sync(vaddr, size, (int)direction);
 406 }
 407
 408 #endif /* __KERNEL__ */
 409 #endif  /* _ASM_DMA_MAPPING_H */