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 */
28extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp);
29extern void __dma_free_coherent(size_t size, void *vaddr);
30extern void __dma_sync(void *vaddr, size_t size, int direction);
31extern 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 */
50struct 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
68static 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
80static 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
91static 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
105static 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
114static 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
123static 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
133static 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
143static 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
154static 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
164static 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
173static 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 */
187extern struct dma_mapping_ops dma_iommu_ops;
188extern struct dma_mapping_ops dma_direct_ops;
189
190extern unsigned long dma_direct_offset;
191
192#else /* CONFIG_PPC64 */
193
194#define dma_supported(dev, mask)	(1)
195
196static 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
206static 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
231static inline void
232dma_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
242static inline dma_addr_t
243dma_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
256static inline dma_addr_t
257dma_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
271static inline int
272dma_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
293static 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
301static 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
309static 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
321static 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
333static 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
350static 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
365static 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
373static 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
381static 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 */
390