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             (*dac_dma_supported)(struct device *dev, u64 mask);
  65         int             (*set_dma_mask)(struct device *dev, u64 dma_mask);
  66 };
  67
  68 static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
  69 {
  70         /* We don't handle the NULL dev case for ISA for now. We could
  71          * do it via an out of line call but it is not needed for now. The
  72          * only ISA DMA device we support is the floppy and we have a hack
  73          * in the floppy driver directly to get a device for us.
  74          */
  75         if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
  76                 return NULL;
  77         return dev->archdata.dma_ops;
  78 }
  79
  80 static inline int dma_supported(struct device *dev, u64 mask)
  81 {
  82         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
  83
  84         if (unlikely(dma_ops == NULL))
  85                 return 0;
  86         if (dma_ops->dma_supported == NULL)
  87                 return 1;
  88         return dma_ops->dma_supported(dev, mask);
  89 }
  90
  91 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
  92 {
  93         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
  94
  95         if (unlikely(dma_ops == NULL))
  96                 return -EIO;
  97         if (dma_ops->set_dma_mask != NULL)
  98                 return dma_ops->set_dma_mask(dev, dma_mask);
  99         if (!dev->dma_mask || !dma_supported(dev, *dev->dma_mask))
 100                 return -EIO;
 101         *dev->dma_mask = dma_mask;
 102         return 0;
 103 }
 104
 105 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 106                                        dma_addr_t *dma_handle, gfp_t flag)
 107 {
 108         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 109
 110         BUG_ON(!dma_ops);
 111         return dma_ops->alloc_coherent(dev, size, dma_handle, flag);
 112 }
 113
 114 static inline void dma_free_coherent(struct device *dev, size_t size,
 115                                      void *cpu_addr, dma_addr_t dma_handle)
 116 {
 117         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 118
 119         BUG_ON(!dma_ops);
 120         dma_ops->free_coherent(dev, size, cpu_addr, dma_handle);
 121 }
 122
 123 static inline dma_addr_t dma_map_single(struct device *dev, void *cpu_addr,
 124                                         size_t size,
 125                                         enum dma_data_direction direction)
 126 {
 127         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 128
 129         BUG_ON(!dma_ops);
 130         return dma_ops->map_single(dev, cpu_addr, size, direction);
 131 }
 132
 133 static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
 134                                     size_t size,
 135                                     enum dma_data_direction direction)
 136 {
 137         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 138
 139         BUG_ON(!dma_ops);
 140         dma_ops->unmap_single(dev, dma_addr, size, direction);
 141 }
 142
 143 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
 144                                       unsigned long offset, size_t size,
 145                                       enum dma_data_direction direction)
 146 {
 147         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 148
 149         BUG_ON(!dma_ops);
 150         return dma_ops->map_single(dev, page_address(page) + offset, size,
 151                         direction);
 152 }
 153
 154 static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
 155                                   size_t size,
 156                                   enum dma_data_direction direction)
 157 {
 158         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 159
 160         BUG_ON(!dma_ops);
 161         dma_ops->unmap_single(dev, dma_address, size, direction);
 162 }
 163
 164 static inline int dma_map_sg(struct device *dev, struct scatterlist *sg,
 165                              int nents, enum dma_data_direction direction)
 166 {
 167         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 168
 169         BUG_ON(!dma_ops);
 170         return dma_ops->map_sg(dev, sg, nents, direction);
 171 }
 172
 173 static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
 174                                 int nhwentries,
 175                                 enum dma_data_direction direction)
 176 {
 177         struct dma_mapping_ops *dma_ops = get_dma_ops(dev);
 178
 179         BUG_ON(!dma_ops);
 180         dma_ops->unmap_sg(dev, sg, nhwentries, direction);
 181 }
 182
 183
 184 /*
 185  * Available generic sets of operations
 186  */
 187 extern struct dma_mapping_ops dma_iommu_ops;
 188 extern struct dma_mapping_ops dma_direct_ops;
 189
 190 extern unsigned long dma_direct_offset;
 191
 192 #else /* CONFIG_PPC64 */
 193
 194 #define dma_supported(dev, mask)        (1)
 195
 196 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
 197 {
 198         if (!dev->dma_mask || !dma_supported(dev, mask))
 199                 return -EIO;
 200
 201         *dev->dma_mask = dma_mask;
 202
 203         return 0;
 204 }
 205
 206 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
 207                                        dma_addr_t * dma_handle,
 208                                        gfp_t gfp)
 209 {
 210 #ifdef CONFIG_NOT_COHERENT_CACHE
 211         return __dma_alloc_coherent(size, dma_handle, gfp);
 212 #else
 213         void *ret;
 214         /* ignore region specifiers */
 215         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
 216
 217         if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
 218                 gfp |= GFP_DMA;
 219
 220         ret = (void *)__get_free_pages(gfp, get_order(size));
 221
 222         if (ret != NULL) {
 223                 memset(ret, 0, size);
 224                 *dma_handle = virt_to_bus(ret);
 225         }
 226
 227         return ret;
 228 #endif
 229 }
 230
 231 static inline void
 232 dma_free_coherent(struct device *dev, size_t size, void *vaddr,
 233                   dma_addr_t dma_handle)
 234 {
 235 #ifdef CONFIG_NOT_COHERENT_CACHE
 236         __dma_free_coherent(size, vaddr);
 237 #else
 238         free_pages((unsigned long)vaddr, get_order(size));
 239 #endif
 240 }
 241
 242 static inline dma_addr_t
 243 dma_map_single(struct device *dev, void *ptr, size_t size,
 244                enum dma_data_direction direction)
 245 {
 246         BUG_ON(direction == DMA_NONE);
 247
 248         __dma_sync(ptr, size, direction);
 249
 250         return virt_to_bus(ptr);
 251 }
 252
 253 /* We do nothing. */
 254 #define dma_unmap_single(dev, addr, size, dir)  ((void)0)
 255
 256 static inline dma_addr_t
 257 dma_map_page(struct device *dev, struct page *page,
 258              unsigned long offset, size_t size,
 259              enum dma_data_direction direction)
 260 {
 261         BUG_ON(direction == DMA_NONE);
 262
 263         __dma_sync_page(page, offset, size, direction);
 264
 265         return page_to_bus(page) + offset;
 266 }
 267
 268 /* We do nothing. */
 269 #define dma_unmap_page(dev, handle, size, dir)  ((void)0)
 270
 271 static inline int
 272 dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
 273            enum dma_data_direction direction)
 274 {
 275         int i;
 276
 277         BUG_ON(direction == DMA_NONE);
 278
 279         for (i = 0; i < nents; i++, sg++) {
 280                 BUG_ON(!sg->page);
 281                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 282                 sg->dma_address = page_to_bus(sg->page) + sg->offset;
 283         }
 284
 285         return nents;
 286 }
 287
 288 /* We don't do anything here. */
 289 #define dma_unmap_sg(dev, sg, nents, dir)       ((void)0)
 290
 291 #endif /* CONFIG_PPC64 */
 292
 293 static inline void dma_sync_single_for_cpu(struct device *dev,
 294                 dma_addr_t dma_handle, size_t size,
 295                 enum dma_data_direction direction)
 296 {
 297         BUG_ON(direction == DMA_NONE);
 298         __dma_sync(bus_to_virt(dma_handle), size, direction);
 299 }
 300
 301 static inline void dma_sync_single_for_device(struct device *dev,
 302                 dma_addr_t dma_handle, size_t size,
 303                 enum dma_data_direction direction)
 304 {
 305         BUG_ON(direction == DMA_NONE);
 306         __dma_sync(bus_to_virt(dma_handle), size, direction);
 307 }
 308
 309 static inline void dma_sync_sg_for_cpu(struct device *dev,
 310                 struct scatterlist *sg, int nents,
 311                 enum dma_data_direction direction)
 312 {
 313         int i;
 314
 315         BUG_ON(direction == DMA_NONE);
 316
 317         for (i = 0; i < nents; i++, sg++)
 318                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 319 }
 320
 321 static inline void dma_sync_sg_for_device(struct device *dev,
 322                 struct scatterlist *sg, int nents,
 323                 enum dma_data_direction direction)
 324 {
 325         int i;
 326
 327         BUG_ON(direction == DMA_NONE);
 328
 329         for (i = 0; i < nents; i++, sg++)
 330                 __dma_sync_page(sg->page, sg->offset, sg->length, direction);
 331 }
 332
 333 static inline int dma_mapping_error(dma_addr_t dma_addr)
 334 {
 335 #ifdef CONFIG_PPC64
 336         return (dma_addr == DMA_ERROR_CODE);
 337 #else
 338         return 0;
 339 #endif
 340 }
 341
 342 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 343 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 344 #ifdef CONFIG_NOT_COHERENT_CACHE
 345 #define dma_is_consistent(d, h) (0)
 346 #else
 347 #define dma_is_consistent(d, h) (1)
 348 #endif
 349
 350 static inline int dma_get_cache_alignment(void)
 351 {
 352 #ifdef CONFIG_PPC64
 353         /* no easy way to get cache size on all processors, so return
 354          * the maximum possible, to be safe */
 355         return (1 << INTERNODE_CACHE_SHIFT);
 356 #else
 357         /*
 358          * Each processor family will define its own L1_CACHE_SHIFT,
 359          * L1_CACHE_BYTES wraps to this, so this is always safe.
 360          */
 361         return L1_CACHE_BYTES;
 362 #endif
 363 }
 364
 365 static inline void dma_sync_single_range_for_cpu(struct device *dev,
 366                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 367                 enum dma_data_direction direction)
 368 {
 369         /* just sync everything for now */
 370         dma_sync_single_for_cpu(dev, dma_handle, offset + size, direction);
 371 }
 372
 373 static inline void dma_sync_single_range_for_device(struct device *dev,
 374                 dma_addr_t dma_handle, unsigned long offset, size_t size,
 375                 enum dma_data_direction direction)
 376 {
 377         /* just sync everything for now */
 378         dma_sync_single_for_device(dev, dma_handle, offset + size, direction);
 379 }
 380
 381 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 382                 enum dma_data_direction direction)
 383 {
 384         BUG_ON(direction == DMA_NONE);
 385         __dma_sync(vaddr, size, (int)direction);
 386 }
 387
 388 #endif /* __KERNEL__ */
 389 #endif  /* _ASM_DMA_MAPPING_H */