summaryrefslogtreecommitdiffstats
path: root/include/linux/dmaengine.h
blob: cb234979fc6bd4dc14a48398e7cc5d7f01311554 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
/*
 * Copyright(c) 2004 - 2006 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * The full GNU General Public License is included in this distribution in the
 * file called COPYING.
 */
#ifndef DMAENGINE_H
#define DMAENGINE_H

#include <linux/device.h>
#include <linux/uio.h>
#include <linux/dma-mapping.h>

/**
 * typedef dma_cookie_t - an opaque DMA cookie
 *
 * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
 */
typedef s32 dma_cookie_t;
#define DMA_MIN_COOKIE	1
#define DMA_MAX_COOKIE	INT_MAX

#define dma_submit_error(cookie) ((cookie) < 0 ? 1 : 0)

/**
 * enum dma_status - DMA transaction status
 * @DMA_SUCCESS: transaction completed successfully
 * @DMA_IN_PROGRESS: transaction not yet processed
 * @DMA_ERROR: transaction failed
 */
enum dma_status {
	DMA_SUCCESS,
	DMA_IN_PROGRESS,
	DMA_ERROR,
};

/**
 * enum dma_transaction_type - DMA transaction types/indexes
 *
 * Note: The DMA_ASYNC_TX capability is not to be set by drivers.  It is
 * automatically set as dma devices are registered.
 */
enum dma_transaction_type {
	DMA_MEMCPY,
	DMA_XOR,
	DMA_PQ,
	DMA_XOR_VAL,
	DMA_PQ_VAL,
	DMA_MEMSET,
	DMA_INTERRUPT,
	DMA_PRIVATE,
	DMA_ASYNC_TX,
	DMA_SLAVE,
};

/* last transaction type for creation of the capabilities mask */
#define DMA_TX_TYPE_END (DMA_SLAVE + 1)


/**
 * enum dma_ctrl_flags - DMA flags to augment operation preparation,
 *  control completion, and communicate status.
 * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of
 *  this transaction
 * @DMA_CTRL_ACK - if clear, the descriptor cannot be reused until the client
 *  acknowledges receipt, i.e. has has a chance to establish any dependency
 *  chains
 * @DMA_COMPL_SKIP_SRC_UNMAP - set to disable dma-unmapping the source buffer(s)
 * @DMA_COMPL_SKIP_DEST_UNMAP - set to disable dma-unmapping the destination(s)
 * @DMA_COMPL_SRC_UNMAP_SINGLE - set to do the source dma-unmapping as single
 * 	(if not set, do the source dma-unmapping as page)
 * @DMA_COMPL_DEST_UNMAP_SINGLE - set to do the destination dma-unmapping as single
 * 	(if not set, do the destination dma-unmapping as page)
 * @DMA_PREP_PQ_DISABLE_P - prevent generation of P while generating Q
 * @DMA_PREP_PQ_DISABLE_Q - prevent generation of Q while generating P
 * @DMA_PREP_CONTINUE - indicate to a driver that it is reusing buffers as
 *  sources that were the result of a previous operation, in the case of a PQ
 *  operation it continues the calculation with new sources
 * @DMA_PREP_FENCE - tell the driver that subsequent operations depend
 *  on the result of this operation
 */
enum dma_ctrl_flags {
	DMA_PREP_INTERRUPT = (1 << 0),
	DMA_CTRL_ACK = (1 << 1),
	DMA_COMPL_SKIP_SRC_UNMAP = (1 << 2),
	DMA_COMPL_SKIP_DEST_UNMAP = (1 << 3),
	DMA_COMPL_SRC_UNMAP_SINGLE = (1 << 4),
	DMA_COMPL_DEST_UNMAP_SINGLE = (1 << 5),
	DMA_PREP_PQ_DISABLE_P = (1 << 6),
	DMA_PREP_PQ_DISABLE_Q = (1 << 7),
	DMA_PREP_CONTINUE = (1 << 8),
	DMA_PREP_FENCE = (1 << 9),
};

/**
 * enum sum_check_bits - bit position of pq_check_flags
 */
enum sum_check_bits {
	SUM_CHECK_P = 0,
	SUM_CHECK_Q = 1,
};

/**
 * enum pq_check_flags - result of async_{xor,pq}_zero_sum operations
 * @SUM_CHECK_P_RESULT - 1 if xor zero sum error, 0 otherwise
 * @SUM_CHECK_Q_RESULT - 1 if reed-solomon zero sum error, 0 otherwise
 */
enum sum_check_flags {
	SUM_CHECK_P_RESULT = (1 << SUM_CHECK_P),
	SUM_CHECK_Q_RESULT = (1 << SUM_CHECK_Q),
};


/**
 * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
 * See linux/cpumask.h
 */
typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;

/**
 * struct dma_chan_percpu - the per-CPU part of struct dma_chan
 * @memcpy_count: transaction counter
 * @bytes_transferred: byte counter
 */

struct dma_chan_percpu {
	/* stats */
	unsigned long memcpy_count;
	unsigned long bytes_transferred;
};

/**
 * struct dma_chan - devices supply DMA channels, clients use them
 * @device: ptr to the dma device who supplies this channel, always !%NULL
 * @cookie: last cookie value returned to client
 * @chan_id: channel ID for sysfs
 * @dev: class device for sysfs
 * @device_node: used to add this to the device chan list
 * @local: per-cpu pointer to a struct dma_chan_percpu
 * @client-count: how many clients are using this channel
 * @table_count: number of appearances in the mem-to-mem allocation table
 * @private: private data for certain client-channel associations
 */
struct dma_chan {
	struct dma_device *device;
	dma_cookie_t cookie;

	/* sysfs */
	int chan_id;
	struct dma_chan_dev *dev;

	struct list_head device_node;
	struct dma_chan_percpu __percpu *local;
	int client_count;
	int table_count;
	void *private;
};

/**
 * struct dma_chan_dev - relate sysfs device node to backing channel device
 * @chan - driver channel device
 * @device - sysfs device
 * @dev_id - parent dma_device dev_id
 * @idr_ref - reference count to gate release of dma_device dev_id
 */
struct dma_chan_dev {
	struct dma_chan *chan;
	struct device device;
	int dev_id;
	atomic_t *idr_ref;
};

static inline const char *dma_chan_name(struct dma_chan *chan)
{
	return dev_name(&chan->dev->device);
}

void dma_chan_cleanup(struct kref *kref);

/**
 * typedef dma_filter_fn - callback filter for dma_request_channel
 * @chan: channel to be reviewed
 * @filter_param: opaque parameter passed through dma_request_channel
 *
 * When this optional parameter is specified in a call to dma_request_channel a
 * suitable channel is passed to this routine for further dispositioning before
 * being returned.  Where 'suitable' indicates a non-busy channel that
 * satisfies the given capability mask.  It returns 'true' to indicate that the
 * channel is suitable.
 */
typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);

typedef void (*dma_async_tx_callback)(void *dma_async_param);
/**
 * struct dma_async_tx_descriptor - async transaction descriptor
 * ---dma generic offload fields---
 * @cookie: tracking cookie for this transaction, set to -EBUSY if
 *	this tx is sitting on a dependency list
 * @flags: flags to augment operation preparation, control completion, and
 * 	communicate status
 * @phys: physical address of the descriptor
 * @chan: target channel for this operation
 * @tx_submit: set the prepared descriptor(s) to be executed by the engine
 * @callback: routine to call after this operation is complete
 * @callback_param: general parameter to pass to the callback routine
 * ---async_tx api specific fields---
 * @next: at completion submit this descriptor
 * @parent: pointer to the next level up in the dependency chain
 * @lock: protect the parent and next pointers
 */
struct dma_async_tx_descriptor {
	dma_cookie_t cookie;
	enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */
	dma_addr_t phys;
	struct dma_chan *chan;
	dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
	dma_async_tx_callback callback;
	void *callback_param;
#ifndef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH
	struct dma_async_tx_descriptor *next;
	struct dma_async_tx_descriptor *parent;
	spinlock_t lock;
#endif
};

#ifdef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH
static inline void txd_lock(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
{
	BUG();
}
static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
{
}
static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
{
}
static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
{
	return NULL;
}
static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
{
	return NULL;
}

#else
static inline void txd_lock(struct dma_async_tx_descriptor *txd)
{
	spin_lock_bh(&txd->lock);
}
static inline void txd_unlock(struct dma_async_tx_descriptor *txd)
{
	spin_unlock_bh(&txd->lock);
}
static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next)
{
	txd->next = next;
	next->parent = txd;
}
static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd)
{
	txd->parent = NULL;
}
static inline void txd_clear_next(struct dma_async_tx_descriptor *txd)
{
	txd->next = NULL;
}
static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd)
{
	return txd->parent;
}
static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd)
{
	return txd->next;
}
#endif

/**
 * struct dma_device - info on the entity supplying DMA services
 * @chancnt: how many DMA channels are supported
 * @privatecnt: how many DMA channels are requested by dma_request_channel
 * @channels: the list of struct dma_chan
 * @global_node: list_head for global dma_device_list
 * @cap_mask: one or more dma_capability flags
 * @max_xor: maximum number of xor sources, 0 if no capability
 * @max_pq: maximum number of PQ sources and PQ-continue capability
 * @copy_align: alignment shift for memcpy operations
 * @xor_align: alignment shift for xor operations
 * @pq_align: alignment shift for pq operations
 * @fill_align: alignment shift for memset operations
 * @dev_id: unique device ID
 * @dev: struct device reference for dma mapping api
 * @device_alloc_chan_resources: allocate resources and return the
 *	number of allocated descriptors
 * @device_free_chan_resources: release DMA channel's resources
 * @device_prep_dma_memcpy: prepares a memcpy operation
 * @device_prep_dma_xor: prepares a xor operation
 * @device_prep_dma_xor_val: prepares a xor validation operation
 * @device_prep_dma_pq: prepares a pq operation
 * @device_prep_dma_pq_val: prepares a pqzero_sum operation
 * @device_prep_dma_memset: prepares a memset operation
 * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
 * @device_prep_slave_sg: prepares a slave dma operation
 * @device_terminate_all: terminate all pending operations
 * @device_is_tx_complete: poll for transaction completion
 * @device_issue_pending: push pending transactions to hardware
 */
struct dma_device {

	unsigned int chancnt;
	unsigned int privatecnt;
	struct list_head channels;
	struct list_head global_node;
	dma_cap_mask_t  cap_mask;
	unsigned short max_xor;
	unsigned short max_pq;
	u8 copy_align;
	u8 xor_align;
	u8 pq_align;
	u8 fill_align;
	#define DMA_HAS_PQ_CONTINUE (1 << 15)

	int dev_id;
	struct device *dev;

	int (*device_alloc_chan_resources)(struct dma_chan *chan);
	void (*device_free_chan_resources)(struct dma_chan *chan);

	struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
		size_t len, unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
		struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
		unsigned int src_cnt, size_t len, unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_xor_val)(
		struct dma_chan *chan, dma_addr_t *src,	unsigned int src_cnt,
		size_t len, enum sum_check_flags *result, unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_pq)(
		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
		unsigned int src_cnt, const unsigned char *scf,
		size_t len, unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_pq_val)(
		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
		unsigned int src_cnt, const unsigned char *scf, size_t len,
		enum sum_check_flags *pqres, unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_memset)(
		struct dma_chan *chan, dma_addr_t dest, int value, size_t len,
		unsigned long flags);
	struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
		struct dma_chan *chan, unsigned long flags);

	struct dma_async_tx_descriptor *(*device_prep_slave_sg)(
		struct dma_chan *chan, struct scatterlist *sgl,
		unsigned int sg_len, enum dma_data_direction direction,
		unsigned long flags);
	void (*device_terminate_all)(struct dma_chan *chan);

	enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
			dma_cookie_t cookie, dma_cookie_t *last,
			dma_cookie_t *used);
	void (*device_issue_pending)(struct dma_chan *chan);
};

static inline bool dmaengine_check_align(u8 align, size_t off1, size_t off2, size_t len)
{
	size_t mask;

	if (!align)
		return true;
	mask = (1 << align) - 1;
	if (mask & (off1 | off2 | len))
		return false;
	return true;
}

static inline bool is_dma_copy_aligned(struct dma_device *dev, size_t off1,
				       size_t off2, size_t len)
{
	return dmaengine_check_align(dev->copy_align, off1, off2, len);
}

static inline bool is_dma_xor_aligned(struct dma_device *dev, size_t off1,
				      size_t off2, size_t len)
{
	return dmaengine_check_align(dev->xor_align, off1, off2, len);
}

static inline bool is_dma_pq_aligned(struct dma_device *dev, size_t off1,
				     size_t off2, size_t len)
{
	return dmaengine_check_align(dev->pq_align, off1, off2, len);
}

static inline bool is_dma_fill_aligned(struct dma_device *dev, size_t off1,
				       size_t off2, size_t len)
{
	return dmaengine_check_align(dev->fill_align, off1, off2, len);
}

static inline void
dma_set_maxpq(struct dma_device *dma, int maxpq, int has_pq_continue)
{
	dma->max_pq = maxpq;
	if (has_pq_continue)
		dma->max_pq |= DMA_HAS_PQ_CONTINUE;
}

static inline bool dmaf_continue(enum dma_ctrl_flags flags)
{
	return (flags & DMA_PREP_CONTINUE) == DMA_PREP_CONTINUE;
}

static inline bool dmaf_p_disabled_continue(enum dma_ctrl_flags flags)
{
	enum dma_ctrl_flags mask = DMA_PREP_CONTINUE | DMA_PREP_PQ_DISABLE_P;

	return (flags & mask) == mask;
}

static inline bool dma_dev_has_pq_continue(struct dma_device *dma)
{
	return (dma->max_pq & DMA_HAS_PQ_CONTINUE) == DMA_HAS_PQ_CONTINUE;
}

static unsigned short dma_dev_to_maxpq(struct dma_device *dma)
{
	return dma->max_pq & ~DMA_HAS_PQ_CONTINUE;
}

/* dma_maxpq - reduce maxpq in the face of continued operations
 * @dma - dma device with PQ capability
 * @flags - to check if DMA_PREP_CONTINUE and DMA_PREP_PQ_DISABLE_P are set
 *
 * When an engine does not support native continuation we need 3 extra
 * source slots to reuse P and Q with the following coefficients:
 * 1/ {00} * P : remove P from Q', but use it as a source for P'
 * 2/ {01} * Q : use Q to continue Q' calculation
 * 3/ {00} * Q : subtract Q from P' to cancel (2)
 *
 * In the case where P is disabled we only need 1 extra source:
 * 1/ {01} * Q : use Q to continue Q' calculation
 */
static inline int dma_maxpq(struct dma_device *dma, enum dma_ctrl_flags flags)
{
	if (dma_dev_has_pq_continue(dma) || !dmaf_continue(flags))
		return dma_dev_to_maxpq(dma);
	else if (dmaf_p_disabled_continue(flags))
		return dma_dev_to_maxpq(dma) - 1;
	else if (dmaf_continue(flags))
		return dma_dev_to_maxpq(dma) - 3;
	BUG();
}

/* --- public DMA engine API --- */

#ifdef CONFIG_DMA_ENGINE
void dmaengine_get(void);
void dmaengine_put(void);
#else
static inline void dmaengine_get(void)
{
}
static inline void dmaengine_put(void)
{
}
#endif

#ifdef CONFIG_NET_DMA
#define net_dmaengine_get()	dmaengine_get()
#define net_dmaengine_put()	dmaengine_put()
#else
static inline void net_dmaengine_get(void)
{
}
static inline void net_dmaengine_put(void)
{
}
#endif

#ifdef CONFIG_ASYNC_TX_DMA
#define async_dmaengine_get()	dmaengine_get()
#define async_dmaengine_put()	dmaengine_put()
#ifdef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH
#define async_dma_find_channel(type) dma_find_channel(DMA_ASYNC_TX)
#else
#define async_dma_find_channel(type) dma_find_channel(type)
#endif /* CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH */
#else
static inline void async_dmaengine_get(void)
{
}
static inline void async_dmaengine_put(void)
{
}
static inline struct dma_chan *
async_dma_find_channel(enum dma_transaction_type type)
{
	return NULL;
}
#endif /* CONFIG_ASYNC_TX_DMA */

dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,
	void *dest, void *src, size_t len);
dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,
	struct page *page, unsigned int offset, void *kdata, size_t len);
dma_cookie_t dma_async_memcpy_pg_to_pg(struct dma_chan *chan,
	struct page *dest_pg, unsigned int dest_off, struct page *src_pg,
	unsigned int src_off, size_t len);
void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
	struct dma_chan *chan);

static inline void async_tx_ack(struct dma_async_tx_descriptor *tx)
{
	tx->flags |= DMA_CTRL_ACK;
}

static inline void async_tx_clear_ack(struct dma_async_tx_descriptor *tx)
{
	tx->flags &= ~DMA_CTRL_ACK;
}

static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx)
{
	return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK;
}

#define first_dma_cap(mask) __first_dma_cap(&(mask))
static inline int __first_dma_cap(const dma_cap_mask_t *srcp)
{
	return min_t(int, DMA_TX_TYPE_END,
		find_first_bit(srcp->bits, DMA_TX_TYPE_END));
}

#define next_dma_cap(n, mask) __next_dma_cap((n), &(mask))
static inline int __next_dma_cap(int n, const dma_cap_mask_t *srcp)
{
	return min_t(int, DMA_TX_TYPE_END,
		find_next_bit(srcp->bits, DMA_TX_TYPE_END, n+1));
}

#define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask))
static inline void
__dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
{
	set_bit(tx_type, dstp->bits);
}

#define dma_cap_clear(tx, mask) __dma_cap_clear((tx), &(mask))
static inline void
__dma_cap_clear(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
{
	clear_bit(tx_type, dstp->bits);
}

#define dma_cap_zero(mask) __dma_cap_zero(&(mask))
static inline void __dma_cap_zero(dma_cap_mask_t *dstp)
{
	bitmap_zero(dstp->bits, DMA_TX_TYPE_END);
}

#define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
static inline int
__dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
{
	return test_bit(tx_type, srcp->bits);
}

#define for_each_dma_cap_mask(cap, mask) \
	for ((cap) = first_dma_cap(mask);	\
		(cap) < DMA_TX_TYPE_END;	\
		(cap) = next_dma_cap((cap), (mask)))

/**
 * dma_async_issue_pending - flush pending transactions to HW
 * @chan: target DMA channel
 *
 * This allows drivers to push copies to HW in batches,
 * reducing MMIO writes where possible.
 */
static inline void dma_async_issue_pending(struct dma_chan *chan)
{
	chan->device->device_issue_pending(chan);
}

#define dma_async_memcpy_issue_pending(chan) dma_async_issue_pending(chan)

/**
 * dma_async_is_tx_complete - poll for transaction completion
 * @chan: DMA channel
 * @cookie: transaction identifier to check status of
 * @last: returns last completed cookie, can be NULL
 * @used: returns last issued cookie, can be NULL
 *
 * If @last and @used are passed in, upon return they reflect the driver
 * internal state and can be used with dma_async_is_complete() to check
 * the status of multiple cookies without re-checking hardware state.
 */
static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
	dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
{
	return chan->device->device_is_tx_complete(chan, cookie, last, used);
}

#define dma_async_memcpy_complete(chan, cookie, last, used)\
	dma_async_is_tx_complete(chan, cookie, last, used)

/**
 * dma_async_is_complete - test a cookie against chan state
 * @cookie: transaction identifier to test status of
 * @last_complete: last know completed transaction
 * @last_used: last cookie value handed out
 *
 * dma_async_is_complete() is used in dma_async_memcpy_complete()
 * the test logic is separated for lightweight testing of multiple cookies
 */
static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
			dma_cookie_t last_complete, dma_cookie_t last_used)
{
	if (last_complete <= last_used) {
		if ((cookie <= last_complete) || (cookie > last_used))
			return DMA_SUCCESS;
	} else {
		if ((cookie <= last_complete) && (cookie > last_used))
			return DMA_SUCCESS;
	}
	return DMA_IN_PROGRESS;
}

enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
#ifdef CONFIG_DMA_ENGINE
enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
void dma_issue_pending_all(void);
#else
static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
{
	return DMA_SUCCESS;
}
static inline void dma_issue_pending_all(void)
{
	do { } while (0);
}
#endif

/* --- DMA device --- */

int dma_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param);
void dma_release_channel(struct dma_chan *chan);

/* --- Helper iov-locking functions --- */

struct dma_page_list {
	char __user *base_address;
	int nr_pages;
	struct page **pages;
};

struct dma_pinned_list {
	int nr_iovecs;
	struct dma_page_list page_list[0];
};

struct dma_pinned_list *dma_pin_iovec_pages(struct iovec *iov, size_t len);
void dma_unpin_iovec_pages(struct dma_pinned_list* pinned_list);

dma_cookie_t dma_memcpy_to_iovec(struct dma_chan *chan, struct iovec *iov,
	struct dma_pinned_list *pinned_list, unsigned char *kdata, size_t len);
dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
	struct dma_pinned_list *pinned_list, struct page *page,
	unsigned int offset, size_t len);

#endif /* DMAENGINE_H */
OpenPOWER on IntegriCloud