arch/arm/include/asm/dma-mapping.h

   1 #ifndef ASMARM_DMA_MAPPING_H
   2 #define ASMARM_DMA_MAPPING_H
   3
   4 #ifdef __KERNEL__
   5
   6 #include <linux/mm_types.h>
   7 #include <linux/scatterlist.h>
   8 #include <linux/dma-debug.h>
   9
  10 #include <asm-generic/dma-coherent.h>
  11 #include <asm/memory.h>
  12
  13 #define DMA_ERROR_CODE  (~0)
  14 extern struct dma_map_ops arm_dma_ops;
  15
  16 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  17 {
  18         if (dev && dev->archdata.dma_ops)
  19                 return dev->archdata.dma_ops;
  20         return &arm_dma_ops;
  21 }
  22
  23 static inline void set_dma_ops(struct device *dev, struct dma_map_ops *ops)
  24 {
  25         BUG_ON(!dev);
  26         dev->archdata.dma_ops = ops;
  27 }
  28
  29 #include <asm-generic/dma-mapping-common.h>
  30
  31 static inline int dma_set_mask(struct device *dev, u64 mask)
  32 {
  33         return get_dma_ops(dev)->set_dma_mask(dev, mask);
  34 }
  35
  36 #ifdef __arch_page_to_dma
  37 #error Please update to __arch_pfn_to_dma
  38 #endif
  39
  40 /*
  41  * dma_to_pfn/pfn_to_dma/dma_to_virt/virt_to_dma are architecture private
  42  * functions used internally by the DMA-mapping API to provide DMA
  43  * addresses. They must not be used by drivers.
  44  */
  45 #ifndef __arch_pfn_to_dma
  46 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  47 {
  48         return (dma_addr_t)__pfn_to_bus(pfn);
  49 }
  50
  51 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  52 {
  53         return __bus_to_pfn(addr);
  54 }
  55
  56 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  57 {
  58         return (void *)__bus_to_virt((unsigned long)addr);
  59 }
  60
  61 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  62 {
  63         return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
  64 }
  65 #else
  66 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
  67 {
  68         return __arch_pfn_to_dma(dev, pfn);
  69 }
  70
  71 static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
  72 {
  73         return __arch_dma_to_pfn(dev, addr);
  74 }
  75
  76 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
  77 {
  78         return __arch_dma_to_virt(dev, addr);
  79 }
  80
  81 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
  82 {
  83         return __arch_virt_to_dma(dev, addr);
  84 }
  85 #endif
  86
  87 /*
  88  * The DMA API is built upon the notion of "buffer ownership".  A buffer
  89  * is either exclusively owned by the CPU (and therefore may be accessed
  90  * by it) or exclusively owned by the DMA device.  These helper functions
  91  * represent the transitions between these two ownership states.
  92  *
  93  * Note, however, that on later ARMs, this notion does not work due to
  94  * speculative prefetches.  We model our approach on the assumption that
  95  * the CPU does do speculative prefetches, which means we clean caches
  96  * before transfers and delay cache invalidation until transfer completion.
  97  *
  98  * Private support functions: these are not part of the API and are
  99  * liable to change.  Drivers must not use these.
 100  */
 101 static inline void __dma_single_cpu_to_dev(const void *kaddr, size_t size,
 102         enum dma_data_direction dir)
 103 {
 104         extern void ___dma_single_cpu_to_dev(const void *, size_t,
 105                 enum dma_data_direction);
 106
 107         if (!arch_is_coherent())
 108                 ___dma_single_cpu_to_dev(kaddr, size, dir);
 109 }
 110
 111 static inline void __dma_single_dev_to_cpu(const void *kaddr, size_t size,
 112         enum dma_data_direction dir)
 113 {
 114         extern void ___dma_single_dev_to_cpu(const void *, size_t,
 115                 enum dma_data_direction);
 116
 117         if (!arch_is_coherent())
 118                 ___dma_single_dev_to_cpu(kaddr, size, dir);
 119 }
 120
 121 static inline void __dma_page_cpu_to_dev(struct page *page, unsigned long off,
 122         size_t size, enum dma_data_direction dir)
 123 {
 124         extern void ___dma_page_cpu_to_dev(struct page *, unsigned long,
 125                 size_t, enum dma_data_direction);
 126
 127         if (!arch_is_coherent())
 128                 ___dma_page_cpu_to_dev(page, off, size, dir);
 129 }
 130
 131 static inline void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
 132         size_t size, enum dma_data_direction dir)
 133 {
 134         extern void ___dma_page_dev_to_cpu(struct page *, unsigned long,
 135                 size_t, enum dma_data_direction);
 136
 137         if (!arch_is_coherent())
 138                 ___dma_page_dev_to_cpu(page, off, size, dir);
 139 }
 140
 141 extern int dma_supported(struct device *, u64);
 142 extern int dma_set_mask(struct device *, u64);
 143 /*
 144  * DMA errors are defined by all-bits-set in the DMA address.
 145  */
 146 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 147 {
 148         return dma_addr == DMA_ERROR_CODE;
 149 }
 150
 151 /*
 152  * Dummy noncoherent implementation.  We don't provide a dma_cache_sync
 153  * function so drivers using this API are highlighted with build warnings.
 154  */
 155 static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
 156                 dma_addr_t *handle, gfp_t gfp)
 157 {
 158         return NULL;
 159 }
 160
 161 static inline void dma_free_noncoherent(struct device *dev, size_t size,
 162                 void *cpu_addr, dma_addr_t handle)
 163 {
 164 }
 165
 166 /**
 167  * dma_alloc_coherent - allocate consistent memory for DMA
 168  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 169  * @size: required memory size
 170  * @handle: bus-specific DMA address
 171  *
 172  * Allocate some uncached, unbuffered memory for a device for
 173  * performing DMA.  This function allocates pages, and will
 174  * return the CPU-viewed address, and sets @handle to be the
 175  * device-viewed address.
 176  */
 177 extern void *dma_alloc_coherent(struct device *, size_t, dma_addr_t *, gfp_t);
 178
 179 /**
 180  * dma_free_coherent - free memory allocated by dma_alloc_coherent
 181  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 182  * @size: size of memory originally requested in dma_alloc_coherent
 183  * @cpu_addr: CPU-view address returned from dma_alloc_coherent
 184  * @handle: device-view address returned from dma_alloc_coherent
 185  *
 186  * Free (and unmap) a DMA buffer previously allocated by
 187  * dma_alloc_coherent().
 188  *
 189  * References to memory and mappings associated with cpu_addr/handle
 190  * during and after this call executing are illegal.
 191  */
 192 extern void dma_free_coherent(struct device *, size_t, void *, dma_addr_t);
 193
 194 /**
 195  * dma_mmap_coherent - map a coherent DMA allocation into user space
 196  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 197  * @vma: vm_area_struct describing requested user mapping
 198  * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
 199  * @handle: device-view address returned from dma_alloc_coherent
 200  * @size: size of memory originally requested in dma_alloc_coherent
 201  *
 202  * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
 203  * into user space.  The coherent DMA buffer must not be freed by the
 204  * driver until the user space mapping has been released.
 205  */
 206 int dma_mmap_coherent(struct device *, struct vm_area_struct *,
 207                 void *, dma_addr_t, size_t);
 208
 209
 210 /**
 211  * dma_alloc_writecombine - allocate writecombining memory for DMA
 212  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
 213  * @size: required memory size
 214  * @handle: bus-specific DMA address
 215  *
 216  * Allocate some uncached, buffered memory for a device for
 217  * performing DMA.  This function allocates pages, and will
 218  * return the CPU-viewed address, and sets @handle to be the
 219  * device-viewed address.
 220  */
 221 extern void *dma_alloc_writecombine(struct device *, size_t, dma_addr_t *,
 222                 gfp_t);
 223
 224 #define dma_free_writecombine(dev,size,cpu_addr,handle) \
 225         dma_free_coherent(dev,size,cpu_addr,handle)
 226
 227 int dma_mmap_writecombine(struct device *, struct vm_area_struct *,
 228                 void *, dma_addr_t, size_t);
 229
 230 /*
 231  * This can be called during boot to increase the size of the consistent
 232  * DMA region above it's default value of 2MB. It must be called before the
 233  * memory allocator is initialised, i.e. before any core_initcall.
 234  */
 235 extern void __init init_consistent_dma_size(unsigned long size);
 236
 237
 238 #ifdef CONFIG_DMABOUNCE
 239 /*
 240  * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
 241  * and utilize bounce buffers as needed to work around limited DMA windows.
 242  *
 243  * On the SA-1111, a bug limits DMA to only certain regions of RAM.
 244  * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
 245  * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
 246  *
 247  * The following are helper functions used by the dmabounce subystem
 248  *
 249  */
 250
 251 /**
 252  * dmabounce_register_dev
 253  *
 254  * @dev: valid struct device pointer
 255  * @small_buf_size: size of buffers to use with small buffer pool
 256  * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
 257  * @needs_bounce_fn: called to determine whether buffer needs bouncing
 258  *
 259  * This function should be called by low-level platform code to register
 260  * a device as requireing DMA buffer bouncing. The function will allocate
 261  * appropriate DMA pools for the device.
 262  */
 263 extern int dmabounce_register_dev(struct device *, unsigned long,
 264                 unsigned long, int (*)(struct device *, dma_addr_t, size_t));
 265
 266 /**
 267  * dmabounce_unregister_dev
 268  *
 269  * @dev: valid struct device pointer
 270  *
 271  * This function should be called by low-level platform code when device
 272  * that was previously registered with dmabounce_register_dev is removed
 273  * from the system.
 274  *
 275  */
 276 extern void dmabounce_unregister_dev(struct device *);
 277
 278 /*
 279  * The DMA API, implemented by dmabounce.c.  See below for descriptions.
 280  */
 281 extern dma_addr_t __dma_map_page(struct device *, struct page *,
 282                 unsigned long, size_t, enum dma_data_direction);
 283 extern void __dma_unmap_page(struct device *, dma_addr_t, size_t,
 284                 enum dma_data_direction);
 285
 286 /*
 287  * Private functions
 288  */
 289 int dmabounce_sync_for_cpu(struct device *, dma_addr_t, size_t, enum dma_data_direction);
 290 int dmabounce_sync_for_device(struct device *, dma_addr_t, size_t, enum dma_data_direction);
 291 #else
 292 static inline int dmabounce_sync_for_cpu(struct device *d, dma_addr_t addr,
 293         size_t size, enum dma_data_direction dir)
 294 {
 295         return 1;
 296 }
 297
 298 static inline int dmabounce_sync_for_device(struct device *d, dma_addr_t addr,
 299         size_t size, enum dma_data_direction dir)
 300 {
 301         return 1;
 302 }
 303
 304
 305 static inline dma_addr_t __dma_map_page(struct device *dev, struct page *page,
 306              unsigned long offset, size_t size, enum dma_data_direction dir)
 307 {
 308         __dma_page_cpu_to_dev(page, offset, size, dir);
 309         return pfn_to_dma(dev, page_to_pfn(page)) + offset;
 310 }
 311
 312 static inline void __dma_unmap_page(struct device *dev, dma_addr_t handle,
 313                 size_t size, enum dma_data_direction dir)
 314 {
 315         __dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, handle)),
 316                 handle & ~PAGE_MASK, size, dir);
 317 }
 318 #endif /* CONFIG_DMABOUNCE */
 319
 320 /*
 321  * The scatter list versions of the above methods.
 322  */
 323 extern int arm_dma_map_sg(struct device *, struct scatterlist *, int,
 324                 enum dma_data_direction, struct dma_attrs *attrs);
 325 extern void arm_dma_unmap_sg(struct device *, struct scatterlist *, int,
 326                 enum dma_data_direction, struct dma_attrs *attrs);
 327 extern void arm_dma_sync_sg_for_cpu(struct device *, struct scatterlist *, int,
 328                 enum dma_data_direction);
 329 extern void arm_dma_sync_sg_for_device(struct device *, struct scatterlist *, int,
 330                 enum dma_data_direction);
 331
 332 #endif /* __KERNEL__ */
 333 #endif