1 #ifndef ASMARM_DMA_MAPPING_H
2 #define ASMARM_DMA_MAPPING_H
6 #include <linux/mm_types.h>
7 #include <linux/scatterlist.h>
9 #include <asm-generic/dma-coherent.h>
10 #include <asm/memory.h>
13 * page_to_dma/dma_to_virt/virt_to_dma are architecture private functions
14 * used internally by the DMA-mapping API to provide DMA addresses. They
15 * must not be used by drivers.
17 #ifndef __arch_page_to_dma
18 static inline dma_addr_t page_to_dma(struct device *dev, struct page *page)
20 return (dma_addr_t)__virt_to_bus((unsigned long)page_address(page));
23 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
25 return (void *)__bus_to_virt(addr);
28 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
30 return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
33 static inline dma_addr_t page_to_dma(struct device *dev, struct page *page)
35 return __arch_page_to_dma(dev, page);
38 static inline void *dma_to_virt(struct device *dev, dma_addr_t addr)
40 return __arch_dma_to_virt(dev, addr);
43 static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
45 return __arch_virt_to_dma(dev, addr);
50 * DMA-consistent mapping functions. These allocate/free a region of
51 * uncached, unwrite-buffered mapped memory space for use with DMA
52 * devices. This is the "generic" version. The PCI specific version
55 * Note: Drivers should NOT use this function directly, as it will break
56 * platforms with CONFIG_DMABOUNCE.
57 * Use the driver DMA support - see dma-mapping.h (dma_sync_*)
59 extern void dma_cache_maint(const void *kaddr, size_t size, int rw);
62 * Return whether the given device DMA address mask can be supported
63 * properly. For example, if your device can only drive the low 24-bits
64 * during bus mastering, then you would pass 0x00ffffff as the mask
67 * FIXME: This should really be a platform specific issue - we should
68 * return false if GFP_DMA allocations may not satisfy the supplied 'mask'.
70 static inline int dma_supported(struct device *dev, u64 mask)
72 return dev->dma_mask && *dev->dma_mask != 0;
75 static inline int dma_set_mask(struct device *dev, u64 dma_mask)
77 if (!dev->dma_mask || !dma_supported(dev, dma_mask))
80 *dev->dma_mask = dma_mask;
85 static inline int dma_get_cache_alignment(void)
90 static inline int dma_is_consistent(struct device *dev, dma_addr_t handle)
92 return !!arch_is_coherent();
96 * DMA errors are defined by all-bits-set in the DMA address.
98 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
100 return dma_addr == ~0;
104 * Dummy noncoherent implementation. We don't provide a dma_cache_sync
105 * function so drivers using this API are highlighted with build warnings.
108 dma_alloc_noncoherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp)
114 dma_free_noncoherent(struct device *dev, size_t size, void *cpu_addr,
120 * dma_alloc_coherent - allocate consistent memory for DMA
121 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
122 * @size: required memory size
123 * @handle: bus-specific DMA address
125 * Allocate some uncached, unbuffered memory for a device for
126 * performing DMA. This function allocates pages, and will
127 * return the CPU-viewed address, and sets @handle to be the
128 * device-viewed address.
131 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp);
134 * dma_free_coherent - free memory allocated by dma_alloc_coherent
135 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
136 * @size: size of memory originally requested in dma_alloc_coherent
137 * @cpu_addr: CPU-view address returned from dma_alloc_coherent
138 * @handle: device-view address returned from dma_alloc_coherent
140 * Free (and unmap) a DMA buffer previously allocated by
141 * dma_alloc_coherent().
143 * References to memory and mappings associated with cpu_addr/handle
144 * during and after this call executing are illegal.
147 dma_free_coherent(struct device *dev, size_t size, void *cpu_addr,
151 * dma_mmap_coherent - map a coherent DMA allocation into user space
152 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
153 * @vma: vm_area_struct describing requested user mapping
154 * @cpu_addr: kernel CPU-view address returned from dma_alloc_coherent
155 * @handle: device-view address returned from dma_alloc_coherent
156 * @size: size of memory originally requested in dma_alloc_coherent
158 * Map a coherent DMA buffer previously allocated by dma_alloc_coherent
159 * into user space. The coherent DMA buffer must not be freed by the
160 * driver until the user space mapping has been released.
162 int dma_mmap_coherent(struct device *dev, struct vm_area_struct *vma,
163 void *cpu_addr, dma_addr_t handle, size_t size);
167 * dma_alloc_writecombine - allocate writecombining 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
172 * Allocate some uncached, buffered 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.
178 dma_alloc_writecombine(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp);
180 #define dma_free_writecombine(dev,size,cpu_addr,handle) \
181 dma_free_coherent(dev,size,cpu_addr,handle)
183 int dma_mmap_writecombine(struct device *dev, struct vm_area_struct *vma,
184 void *cpu_addr, dma_addr_t handle, size_t size);
187 #ifdef CONFIG_DMABOUNCE
189 * For SA-1111, IXP425, and ADI systems the dma-mapping functions are "magic"
190 * and utilize bounce buffers as needed to work around limited DMA windows.
192 * On the SA-1111, a bug limits DMA to only certain regions of RAM.
193 * On the IXP425, the PCI inbound window is 64MB (256MB total RAM)
194 * On some ADI engineering systems, PCI inbound window is 32MB (12MB total RAM)
196 * The following are helper functions used by the dmabounce subystem
201 * dmabounce_register_dev
203 * @dev: valid struct device pointer
204 * @small_buf_size: size of buffers to use with small buffer pool
205 * @large_buf_size: size of buffers to use with large buffer pool (can be 0)
207 * This function should be called by low-level platform code to register
208 * a device as requireing DMA buffer bouncing. The function will allocate
209 * appropriate DMA pools for the device.
212 extern int dmabounce_register_dev(struct device *, unsigned long, unsigned long);
215 * dmabounce_unregister_dev
217 * @dev: valid struct device pointer
219 * This function should be called by low-level platform code when device
220 * that was previously registered with dmabounce_register_dev is removed
224 extern void dmabounce_unregister_dev(struct device *);
229 * @dev: valid struct device pointer
230 * @dma_handle: dma_handle of unbounced buffer
231 * @size: size of region being mapped
233 * Platforms that utilize the dmabounce mechanism must implement
236 * The dmabounce routines call this function whenever a dma-mapping
237 * is requested to determine whether a given buffer needs to be bounced
238 * or not. The function must return 0 if the buffer is OK for
239 * DMA access and 1 if the buffer needs to be bounced.
242 extern int dma_needs_bounce(struct device*, dma_addr_t, size_t);
247 int dmabounce_sync_for_cpu(struct device *, dma_addr_t, unsigned long,
248 size_t, enum dma_data_direction);
249 int dmabounce_sync_for_device(struct device *, dma_addr_t, unsigned long,
250 size_t, enum dma_data_direction);
252 #define dmabounce_sync_for_cpu(dev,dma,off,sz,dir) (1)
253 #define dmabounce_sync_for_device(dev,dma,off,sz,dir) (1)
254 #endif /* CONFIG_DMABOUNCE */
258 * dma_map_single - map a single buffer for streaming DMA
259 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
260 * @cpu_addr: CPU direct mapped address of buffer
261 * @size: size of buffer to map
262 * @dir: DMA transfer direction
264 * Ensure that any data held in the cache is appropriately discarded
267 * The device owns this memory once this call has completed. The CPU
268 * can regain ownership by calling dma_unmap_single() or
269 * dma_sync_single_for_cpu().
271 #ifndef CONFIG_DMABOUNCE
272 static inline dma_addr_t
273 dma_map_single(struct device *dev, void *cpu_addr, size_t size,
274 enum dma_data_direction dir)
276 if (!arch_is_coherent())
277 dma_cache_maint(cpu_addr, size, dir);
279 return virt_to_dma(dev, cpu_addr);
282 extern dma_addr_t dma_map_single(struct device *,void *, size_t, enum dma_data_direction);
286 * dma_map_page - map a portion of a page for streaming DMA
287 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
288 * @page: page that buffer resides in
289 * @offset: offset into page for start of buffer
290 * @size: size of buffer to map
291 * @dir: DMA transfer direction
293 * Ensure that any data held in the cache is appropriately discarded
296 * The device owns this memory once this call has completed. The CPU
297 * can regain ownership by calling dma_unmap_page() or
298 * dma_sync_single_for_cpu().
300 #ifndef CONFIG_DMABOUNCE
301 static inline dma_addr_t
302 dma_map_page(struct device *dev, struct page *page,
303 unsigned long offset, size_t size,
304 enum dma_data_direction dir)
306 if (!arch_is_coherent())
307 dma_cache_maint(page_address(page) + offset, size, dir);
309 return page_to_dma(dev, page) + offset;
312 extern dma_addr_t dma_map_page(struct device *dev, struct page *page,
313 unsigned long offset, size_t size,
314 enum dma_data_direction dir);
318 * dma_unmap_single - unmap a single buffer previously mapped
319 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
320 * @handle: DMA address of buffer
321 * @size: size of buffer to map
322 * @dir: DMA transfer direction
324 * Unmap a single streaming mode DMA translation. The handle and size
325 * must match what was provided in the previous dma_map_single() call.
326 * All other usages are undefined.
328 * After this call, reads by the CPU to the buffer are guaranteed to see
329 * whatever the device wrote there.
331 #ifndef CONFIG_DMABOUNCE
333 dma_unmap_single(struct device *dev, dma_addr_t handle, size_t size,
334 enum dma_data_direction dir)
339 extern void dma_unmap_single(struct device *, dma_addr_t, size_t, enum dma_data_direction);
343 * dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
344 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
345 * @handle: DMA address of buffer
346 * @size: size of buffer to map
347 * @dir: DMA transfer direction
349 * Unmap a single streaming mode DMA translation. The handle and size
350 * must match what was provided in the previous dma_map_single() call.
351 * All other usages are undefined.
353 * After this call, reads by the CPU to the buffer are guaranteed to see
354 * whatever the device wrote there.
357 dma_unmap_page(struct device *dev, dma_addr_t handle, size_t size,
358 enum dma_data_direction dir)
360 dma_unmap_single(dev, handle, size, dir);
364 * dma_sync_single_range_for_cpu
365 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
366 * @handle: DMA address of buffer
367 * @offset: offset of region to start sync
368 * @size: size of region to sync
369 * @dir: DMA transfer direction (same as passed to dma_map_single)
371 * Make physical memory consistent for a single streaming mode DMA
372 * translation after a transfer.
374 * If you perform a dma_map_single() but wish to interrogate the
375 * buffer using the cpu, yet do not wish to teardown the PCI dma
376 * mapping, you must call this function before doing so. At the
377 * next point you give the PCI dma address back to the card, you
378 * must first the perform a dma_sync_for_device, and then the
379 * device again owns the buffer.
382 dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t handle,
383 unsigned long offset, size_t size,
384 enum dma_data_direction dir)
386 if (!dmabounce_sync_for_cpu(dev, handle, offset, size, dir))
389 if (!arch_is_coherent())
390 dma_cache_maint(dma_to_virt(dev, handle) + offset, size, dir);
394 dma_sync_single_range_for_device(struct device *dev, dma_addr_t handle,
395 unsigned long offset, size_t size,
396 enum dma_data_direction dir)
398 if (!dmabounce_sync_for_device(dev, handle, offset, size, dir))
401 if (!arch_is_coherent())
402 dma_cache_maint(dma_to_virt(dev, handle) + offset, size, dir);
406 dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle, size_t size,
407 enum dma_data_direction dir)
409 dma_sync_single_range_for_cpu(dev, handle, 0, size, dir);
413 dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
414 enum dma_data_direction dir)
416 dma_sync_single_range_for_device(dev, handle, 0, size, dir);
420 * The scatter list versions of the above methods.
422 extern int dma_map_sg(struct device *, struct scatterlist *, int, enum dma_data_direction);
423 extern void dma_unmap_sg(struct device *, struct scatterlist *, int, enum dma_data_direction);
424 extern void dma_sync_sg_for_cpu(struct device*, struct scatterlist*, int, enum dma_data_direction);
425 extern void dma_sync_sg_for_device(struct device*, struct scatterlist*, int, enum dma_data_direction);
428 #endif /* __KERNEL__ */