summaryrefslogtreecommitdiff
path: root/drivers/dma/dw-edma/dw-edma-core.c
blob: 468d1097a1ece2e70a1fc8be8942a2f64ff3477f (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
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
 * Synopsys DesignWare eDMA core driver
 *
 * Author: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
 */

#include <linux/module.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/pm_runtime.h>
#include <linux/dmaengine.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/dma/edma.h>
#include <linux/dma-mapping.h>

#include "dw-edma-core.h"
#include "dw-edma-v0-core.h"
#include "../dmaengine.h"
#include "../virt-dma.h"

static inline
struct device *dchan2dev(struct dma_chan *dchan)
{
	return &dchan->dev->device;
}

static inline
struct device *chan2dev(struct dw_edma_chan *chan)
{
	return &chan->vc.chan.dev->device;
}

static inline
struct dw_edma_desc *vd2dw_edma_desc(struct virt_dma_desc *vd)
{
	return container_of(vd, struct dw_edma_desc, vd);
}

static struct dw_edma_burst *dw_edma_alloc_burst(struct dw_edma_chunk *chunk)
{
	struct dw_edma_burst *burst;

	burst = kzalloc(sizeof(*burst), GFP_NOWAIT);
	if (unlikely(!burst))
		return NULL;

	INIT_LIST_HEAD(&burst->list);
	if (chunk->burst) {
		/* Create and add new element into the linked list */
		chunk->bursts_alloc++;
		list_add_tail(&burst->list, &chunk->burst->list);
	} else {
		/* List head */
		chunk->bursts_alloc = 0;
		chunk->burst = burst;
	}

	return burst;
}

static struct dw_edma_chunk *dw_edma_alloc_chunk(struct dw_edma_desc *desc)
{
	struct dw_edma_chan *chan = desc->chan;
	struct dw_edma *dw = chan->chip->dw;
	struct dw_edma_chunk *chunk;

	chunk = kzalloc(sizeof(*chunk), GFP_NOWAIT);
	if (unlikely(!chunk))
		return NULL;

	INIT_LIST_HEAD(&chunk->list);
	chunk->chan = chan;
	/* Toggling change bit (CB) in each chunk, this is a mechanism to
	 * inform the eDMA HW block that this is a new linked list ready
	 * to be consumed.
	 *  - Odd chunks originate CB equal to 0
	 *  - Even chunks originate CB equal to 1
	 */
	chunk->cb = !(desc->chunks_alloc % 2);
	if (chan->dir == EDMA_DIR_WRITE) {
		chunk->ll_region.paddr = dw->ll_region_wr[chan->id].paddr;
		chunk->ll_region.vaddr = dw->ll_region_wr[chan->id].vaddr;
	} else {
		chunk->ll_region.paddr = dw->ll_region_rd[chan->id].paddr;
		chunk->ll_region.vaddr = dw->ll_region_rd[chan->id].vaddr;
	}

	if (desc->chunk) {
		/* Create and add new element into the linked list */
		if (!dw_edma_alloc_burst(chunk)) {
			kfree(chunk);
			return NULL;
		}
		desc->chunks_alloc++;
		list_add_tail(&chunk->list, &desc->chunk->list);
	} else {
		/* List head */
		chunk->burst = NULL;
		desc->chunks_alloc = 0;
		desc->chunk = chunk;
	}

	return chunk;
}

static struct dw_edma_desc *dw_edma_alloc_desc(struct dw_edma_chan *chan)
{
	struct dw_edma_desc *desc;

	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
	if (unlikely(!desc))
		return NULL;

	desc->chan = chan;
	if (!dw_edma_alloc_chunk(desc)) {
		kfree(desc);
		return NULL;
	}

	return desc;
}

static void dw_edma_free_burst(struct dw_edma_chunk *chunk)
{
	struct dw_edma_burst *child, *_next;

	/* Remove all the list elements */
	list_for_each_entry_safe(child, _next, &chunk->burst->list, list) {
		list_del(&child->list);
		kfree(child);
		chunk->bursts_alloc--;
	}

	/* Remove the list head */
	kfree(child);
	chunk->burst = NULL;
}

static void dw_edma_free_chunk(struct dw_edma_desc *desc)
{
	struct dw_edma_chunk *child, *_next;

	if (!desc->chunk)
		return;

	/* Remove all the list elements */
	list_for_each_entry_safe(child, _next, &desc->chunk->list, list) {
		dw_edma_free_burst(child);
		list_del(&child->list);
		kfree(child);
		desc->chunks_alloc--;
	}

	/* Remove the list head */
	kfree(child);
	desc->chunk = NULL;
}

static void dw_edma_free_desc(struct dw_edma_desc *desc)
{
	dw_edma_free_chunk(desc);
	kfree(desc);
}

static void vchan_free_desc(struct virt_dma_desc *vdesc)
{
	dw_edma_free_desc(vd2dw_edma_desc(vdesc));
}

static void dw_edma_start_transfer(struct dw_edma_chan *chan)
{
	struct dw_edma_chunk *child;
	struct dw_edma_desc *desc;
	struct virt_dma_desc *vd;

	vd = vchan_next_desc(&chan->vc);
	if (!vd)
		return;

	desc = vd2dw_edma_desc(vd);
	if (!desc)
		return;

	child = list_first_entry_or_null(&desc->chunk->list,
					 struct dw_edma_chunk, list);
	if (!child)
		return;

	dw_edma_v0_core_start(child, !desc->xfer_sz);
	desc->xfer_sz += child->ll_region.sz;
	dw_edma_free_burst(child);
	list_del(&child->list);
	kfree(child);
	desc->chunks_alloc--;
}

static int dw_edma_device_config(struct dma_chan *dchan,
				 struct dma_slave_config *config)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);

	memcpy(&chan->config, config, sizeof(*config));
	chan->configured = true;

	return 0;
}

static int dw_edma_device_pause(struct dma_chan *dchan)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	int err = 0;

	if (!chan->configured)
		err = -EPERM;
	else if (chan->status != EDMA_ST_BUSY)
		err = -EPERM;
	else if (chan->request != EDMA_REQ_NONE)
		err = -EPERM;
	else
		chan->request = EDMA_REQ_PAUSE;

	return err;
}

static int dw_edma_device_resume(struct dma_chan *dchan)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	int err = 0;

	if (!chan->configured) {
		err = -EPERM;
	} else if (chan->status != EDMA_ST_PAUSE) {
		err = -EPERM;
	} else if (chan->request != EDMA_REQ_NONE) {
		err = -EPERM;
	} else {
		chan->status = EDMA_ST_BUSY;
		dw_edma_start_transfer(chan);
	}

	return err;
}

static int dw_edma_device_terminate_all(struct dma_chan *dchan)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	int err = 0;

	if (!chan->configured) {
		/* Do nothing */
	} else if (chan->status == EDMA_ST_PAUSE) {
		chan->status = EDMA_ST_IDLE;
		chan->configured = false;
	} else if (chan->status == EDMA_ST_IDLE) {
		chan->configured = false;
	} else if (dw_edma_v0_core_ch_status(chan) == DMA_COMPLETE) {
		/*
		 * The channel is in a false BUSY state, probably didn't
		 * receive or lost an interrupt
		 */
		chan->status = EDMA_ST_IDLE;
		chan->configured = false;
	} else if (chan->request > EDMA_REQ_PAUSE) {
		err = -EPERM;
	} else {
		chan->request = EDMA_REQ_STOP;
	}

	return err;
}

static void dw_edma_device_issue_pending(struct dma_chan *dchan)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	unsigned long flags;

	spin_lock_irqsave(&chan->vc.lock, flags);
	if (chan->configured && chan->request == EDMA_REQ_NONE &&
	    chan->status == EDMA_ST_IDLE && vchan_issue_pending(&chan->vc)) {
		chan->status = EDMA_ST_BUSY;
		dw_edma_start_transfer(chan);
	}
	spin_unlock_irqrestore(&chan->vc.lock, flags);
}

static enum dma_status
dw_edma_device_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
			 struct dma_tx_state *txstate)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	struct dw_edma_desc *desc;
	struct virt_dma_desc *vd;
	unsigned long flags;
	enum dma_status ret;
	u32 residue = 0;

	ret = dma_cookie_status(dchan, cookie, txstate);
	if (ret == DMA_COMPLETE)
		return ret;

	if (ret == DMA_IN_PROGRESS && chan->status == EDMA_ST_PAUSE)
		ret = DMA_PAUSED;

	if (!txstate)
		goto ret_residue;

	spin_lock_irqsave(&chan->vc.lock, flags);
	vd = vchan_find_desc(&chan->vc, cookie);
	if (vd) {
		desc = vd2dw_edma_desc(vd);
		if (desc)
			residue = desc->alloc_sz - desc->xfer_sz;
	}
	spin_unlock_irqrestore(&chan->vc.lock, flags);

ret_residue:
	dma_set_residue(txstate, residue);

	return ret;
}

static struct dma_async_tx_descriptor *
dw_edma_device_transfer(struct dw_edma_transfer *xfer)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(xfer->dchan);
	enum dma_transfer_direction dir = xfer->direction;
	phys_addr_t src_addr, dst_addr;
	struct scatterlist *sg = NULL;
	struct dw_edma_chunk *chunk;
	struct dw_edma_burst *burst;
	struct dw_edma_desc *desc;
	u32 cnt = 0;
	int i;

	if (!chan->configured)
		return NULL;

	switch (chan->config.direction) {
	case DMA_DEV_TO_MEM: /* local DMA */
		if (dir == DMA_DEV_TO_MEM && chan->dir == EDMA_DIR_READ)
			break;
		return NULL;
	case DMA_MEM_TO_DEV: /* local DMA */
		if (dir == DMA_MEM_TO_DEV && chan->dir == EDMA_DIR_WRITE)
			break;
		return NULL;
	default: /* remote DMA */
		if (dir == DMA_MEM_TO_DEV && chan->dir == EDMA_DIR_READ)
			break;
		if (dir == DMA_DEV_TO_MEM && chan->dir == EDMA_DIR_WRITE)
			break;
		return NULL;
	}

	if (xfer->type == EDMA_XFER_CYCLIC) {
		if (!xfer->xfer.cyclic.len || !xfer->xfer.cyclic.cnt)
			return NULL;
	} else if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
		if (xfer->xfer.sg.len < 1)
			return NULL;
	} else if (xfer->type == EDMA_XFER_INTERLEAVED) {
		if (!xfer->xfer.il->numf)
			return NULL;
		if (xfer->xfer.il->numf > 0 && xfer->xfer.il->frame_size > 0)
			return NULL;
	} else {
		return NULL;
	}

	desc = dw_edma_alloc_desc(chan);
	if (unlikely(!desc))
		goto err_alloc;

	chunk = dw_edma_alloc_chunk(desc);
	if (unlikely(!chunk))
		goto err_alloc;

	if (xfer->type == EDMA_XFER_INTERLEAVED) {
		src_addr = xfer->xfer.il->src_start;
		dst_addr = xfer->xfer.il->dst_start;
	} else {
		src_addr = chan->config.src_addr;
		dst_addr = chan->config.dst_addr;
	}

	if (xfer->type == EDMA_XFER_CYCLIC) {
		cnt = xfer->xfer.cyclic.cnt;
	} else if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
		cnt = xfer->xfer.sg.len;
		sg = xfer->xfer.sg.sgl;
	} else if (xfer->type == EDMA_XFER_INTERLEAVED) {
		if (xfer->xfer.il->numf > 0)
			cnt = xfer->xfer.il->numf;
		else
			cnt = xfer->xfer.il->frame_size;
	}

	for (i = 0; i < cnt; i++) {
		if (xfer->type == EDMA_XFER_SCATTER_GATHER && !sg)
			break;

		if (chunk->bursts_alloc == chan->ll_max) {
			chunk = dw_edma_alloc_chunk(desc);
			if (unlikely(!chunk))
				goto err_alloc;
		}

		burst = dw_edma_alloc_burst(chunk);
		if (unlikely(!burst))
			goto err_alloc;

		if (xfer->type == EDMA_XFER_CYCLIC)
			burst->sz = xfer->xfer.cyclic.len;
		else if (xfer->type == EDMA_XFER_SCATTER_GATHER)
			burst->sz = sg_dma_len(sg);
		else if (xfer->type == EDMA_XFER_INTERLEAVED)
			burst->sz = xfer->xfer.il->sgl[i].size;

		chunk->ll_region.sz += burst->sz;
		desc->alloc_sz += burst->sz;

		if (chan->dir == EDMA_DIR_WRITE) {
			burst->sar = src_addr;
			if (xfer->type == EDMA_XFER_CYCLIC) {
				burst->dar = xfer->xfer.cyclic.paddr;
			} else if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
				src_addr += sg_dma_len(sg);
				burst->dar = sg_dma_address(sg);
				/* Unlike the typical assumption by other
				 * drivers/IPs the peripheral memory isn't
				 * a FIFO memory, in this case, it's a
				 * linear memory and that why the source
				 * and destination addresses are increased
				 * by the same portion (data length)
				 */
			}
		} else {
			burst->dar = dst_addr;
			if (xfer->type == EDMA_XFER_CYCLIC) {
				burst->sar = xfer->xfer.cyclic.paddr;
			} else if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
				dst_addr += sg_dma_len(sg);
				burst->sar = sg_dma_address(sg);
				/* Unlike the typical assumption by other
				 * drivers/IPs the peripheral memory isn't
				 * a FIFO memory, in this case, it's a
				 * linear memory and that why the source
				 * and destination addresses are increased
				 * by the same portion (data length)
				 */
			}
		}

		if (xfer->type == EDMA_XFER_SCATTER_GATHER) {
			sg = sg_next(sg);
		} else if (xfer->type == EDMA_XFER_INTERLEAVED &&
			   xfer->xfer.il->frame_size > 0) {
			struct dma_interleaved_template *il = xfer->xfer.il;
			struct data_chunk *dc = &il->sgl[i];

			if (il->src_sgl) {
				src_addr += burst->sz;
				src_addr += dmaengine_get_src_icg(il, dc);
			}

			if (il->dst_sgl) {
				dst_addr += burst->sz;
				dst_addr += dmaengine_get_dst_icg(il, dc);
			}
		}
	}

	return vchan_tx_prep(&chan->vc, &desc->vd, xfer->flags);

err_alloc:
	if (desc)
		dw_edma_free_desc(desc);

	return NULL;
}

static struct dma_async_tx_descriptor *
dw_edma_device_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
			     unsigned int len,
			     enum dma_transfer_direction direction,
			     unsigned long flags, void *context)
{
	struct dw_edma_transfer xfer;

	xfer.dchan = dchan;
	xfer.direction = direction;
	xfer.xfer.sg.sgl = sgl;
	xfer.xfer.sg.len = len;
	xfer.flags = flags;
	xfer.type = EDMA_XFER_SCATTER_GATHER;

	return dw_edma_device_transfer(&xfer);
}

static struct dma_async_tx_descriptor *
dw_edma_device_prep_dma_cyclic(struct dma_chan *dchan, dma_addr_t paddr,
			       size_t len, size_t count,
			       enum dma_transfer_direction direction,
			       unsigned long flags)
{
	struct dw_edma_transfer xfer;

	xfer.dchan = dchan;
	xfer.direction = direction;
	xfer.xfer.cyclic.paddr = paddr;
	xfer.xfer.cyclic.len = len;
	xfer.xfer.cyclic.cnt = count;
	xfer.flags = flags;
	xfer.type = EDMA_XFER_CYCLIC;

	return dw_edma_device_transfer(&xfer);
}

static struct dma_async_tx_descriptor *
dw_edma_device_prep_interleaved_dma(struct dma_chan *dchan,
				    struct dma_interleaved_template *ilt,
				    unsigned long flags)
{
	struct dw_edma_transfer xfer;

	xfer.dchan = dchan;
	xfer.direction = ilt->dir;
	xfer.xfer.il = ilt;
	xfer.flags = flags;
	xfer.type = EDMA_XFER_INTERLEAVED;

	return dw_edma_device_transfer(&xfer);
}

static void dw_edma_done_interrupt(struct dw_edma_chan *chan)
{
	struct dw_edma_desc *desc;
	struct virt_dma_desc *vd;
	unsigned long flags;

	dw_edma_v0_core_clear_done_int(chan);

	spin_lock_irqsave(&chan->vc.lock, flags);
	vd = vchan_next_desc(&chan->vc);
	if (vd) {
		switch (chan->request) {
		case EDMA_REQ_NONE:
			desc = vd2dw_edma_desc(vd);
			if (desc->chunks_alloc) {
				chan->status = EDMA_ST_BUSY;
				dw_edma_start_transfer(chan);
			} else {
				list_del(&vd->node);
				vchan_cookie_complete(vd);
				chan->status = EDMA_ST_IDLE;
			}
			break;

		case EDMA_REQ_STOP:
			list_del(&vd->node);
			vchan_cookie_complete(vd);
			chan->request = EDMA_REQ_NONE;
			chan->status = EDMA_ST_IDLE;
			break;

		case EDMA_REQ_PAUSE:
			chan->request = EDMA_REQ_NONE;
			chan->status = EDMA_ST_PAUSE;
			break;

		default:
			break;
		}
	}
	spin_unlock_irqrestore(&chan->vc.lock, flags);
}

static void dw_edma_abort_interrupt(struct dw_edma_chan *chan)
{
	struct virt_dma_desc *vd;
	unsigned long flags;

	dw_edma_v0_core_clear_abort_int(chan);

	spin_lock_irqsave(&chan->vc.lock, flags);
	vd = vchan_next_desc(&chan->vc);
	if (vd) {
		list_del(&vd->node);
		vchan_cookie_complete(vd);
	}
	spin_unlock_irqrestore(&chan->vc.lock, flags);
	chan->request = EDMA_REQ_NONE;
	chan->status = EDMA_ST_IDLE;
}

static irqreturn_t dw_edma_interrupt(int irq, void *data, bool write)
{
	struct dw_edma_irq *dw_irq = data;
	struct dw_edma *dw = dw_irq->dw;
	unsigned long total, pos, val;
	unsigned long off;
	u32 mask;

	if (write) {
		total = dw->wr_ch_cnt;
		off = 0;
		mask = dw_irq->wr_mask;
	} else {
		total = dw->rd_ch_cnt;
		off = dw->wr_ch_cnt;
		mask = dw_irq->rd_mask;
	}

	val = dw_edma_v0_core_status_done_int(dw, write ?
							  EDMA_DIR_WRITE :
							  EDMA_DIR_READ);
	val &= mask;
	for_each_set_bit(pos, &val, total) {
		struct dw_edma_chan *chan = &dw->chan[pos + off];

		dw_edma_done_interrupt(chan);
	}

	val = dw_edma_v0_core_status_abort_int(dw, write ?
							   EDMA_DIR_WRITE :
							   EDMA_DIR_READ);
	val &= mask;
	for_each_set_bit(pos, &val, total) {
		struct dw_edma_chan *chan = &dw->chan[pos + off];

		dw_edma_abort_interrupt(chan);
	}

	return IRQ_HANDLED;
}

static inline irqreturn_t dw_edma_interrupt_write(int irq, void *data)
{
	return dw_edma_interrupt(irq, data, true);
}

static inline irqreturn_t dw_edma_interrupt_read(int irq, void *data)
{
	return dw_edma_interrupt(irq, data, false);
}

static irqreturn_t dw_edma_interrupt_common(int irq, void *data)
{
	dw_edma_interrupt(irq, data, true);
	dw_edma_interrupt(irq, data, false);

	return IRQ_HANDLED;
}

static int dw_edma_alloc_chan_resources(struct dma_chan *dchan)
{
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);

	if (chan->status != EDMA_ST_IDLE)
		return -EBUSY;

	pm_runtime_get(chan->chip->dev);

	return 0;
}

static void dw_edma_free_chan_resources(struct dma_chan *dchan)
{
	unsigned long timeout = jiffies + msecs_to_jiffies(5000);
	struct dw_edma_chan *chan = dchan2dw_edma_chan(dchan);
	int ret;

	while (time_before(jiffies, timeout)) {
		ret = dw_edma_device_terminate_all(dchan);
		if (!ret)
			break;

		if (time_after_eq(jiffies, timeout))
			return;

		cpu_relax();
	}

	pm_runtime_put(chan->chip->dev);
}

static int dw_edma_channel_setup(struct dw_edma_chip *chip, bool write,
				 u32 wr_alloc, u32 rd_alloc)
{
	struct dw_edma_region *dt_region;
	struct device *dev = chip->dev;
	struct dw_edma *dw = chip->dw;
	struct dw_edma_chan *chan;
	struct dw_edma_irq *irq;
	struct dma_device *dma;
	u32 alloc, off_alloc;
	u32 i, j, cnt;
	int err = 0;
	u32 pos;

	if (write) {
		i = 0;
		cnt = dw->wr_ch_cnt;
		dma = &dw->wr_edma;
		alloc = wr_alloc;
		off_alloc = 0;
	} else {
		i = dw->wr_ch_cnt;
		cnt = dw->rd_ch_cnt;
		dma = &dw->rd_edma;
		alloc = rd_alloc;
		off_alloc = wr_alloc;
	}

	INIT_LIST_HEAD(&dma->channels);
	for (j = 0; (alloc || dw->nr_irqs == 1) && j < cnt; j++, i++) {
		chan = &dw->chan[i];

		dt_region = devm_kzalloc(dev, sizeof(*dt_region), GFP_KERNEL);
		if (!dt_region)
			return -ENOMEM;

		chan->vc.chan.private = dt_region;

		chan->chip = chip;
		chan->id = j;
		chan->dir = write ? EDMA_DIR_WRITE : EDMA_DIR_READ;
		chan->configured = false;
		chan->request = EDMA_REQ_NONE;
		chan->status = EDMA_ST_IDLE;

		if (write)
			chan->ll_max = (dw->ll_region_wr[j].sz / EDMA_LL_SZ);
		else
			chan->ll_max = (dw->ll_region_rd[j].sz / EDMA_LL_SZ);
		chan->ll_max -= 1;

		dev_vdbg(dev, "L. List:\tChannel %s[%u] max_cnt=%u\n",
			 write ? "write" : "read", j, chan->ll_max);

		if (dw->nr_irqs == 1)
			pos = 0;
		else
			pos = off_alloc + (j % alloc);

		irq = &dw->irq[pos];

		if (write)
			irq->wr_mask |= BIT(j);
		else
			irq->rd_mask |= BIT(j);

		irq->dw = dw;
		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));

		dev_vdbg(dev, "MSI:\t\tChannel %s[%u] addr=0x%.8x%.8x, data=0x%.8x\n",
			 write ? "write" : "read", j,
			 chan->msi.address_hi, chan->msi.address_lo,
			 chan->msi.data);

		chan->vc.desc_free = vchan_free_desc;
		vchan_init(&chan->vc, dma);

		if (write) {
			dt_region->paddr = dw->dt_region_wr[j].paddr;
			dt_region->vaddr = dw->dt_region_wr[j].vaddr;
			dt_region->sz = dw->dt_region_wr[j].sz;
		} else {
			dt_region->paddr = dw->dt_region_rd[j].paddr;
			dt_region->vaddr = dw->dt_region_rd[j].vaddr;
			dt_region->sz = dw->dt_region_rd[j].sz;
		}

		dw_edma_v0_core_device_config(chan);
	}

	/* Set DMA channel capabilities */
	dma_cap_zero(dma->cap_mask);
	dma_cap_set(DMA_SLAVE, dma->cap_mask);
	dma_cap_set(DMA_CYCLIC, dma->cap_mask);
	dma_cap_set(DMA_PRIVATE, dma->cap_mask);
	dma_cap_set(DMA_INTERLEAVE, dma->cap_mask);
	dma->directions = BIT(write ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV);
	dma->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
	dma->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
	dma->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
	dma->chancnt = cnt;

	/* Set DMA channel callbacks */
	dma->dev = chip->dev;
	dma->device_alloc_chan_resources = dw_edma_alloc_chan_resources;
	dma->device_free_chan_resources = dw_edma_free_chan_resources;
	dma->device_config = dw_edma_device_config;
	dma->device_pause = dw_edma_device_pause;
	dma->device_resume = dw_edma_device_resume;
	dma->device_terminate_all = dw_edma_device_terminate_all;
	dma->device_issue_pending = dw_edma_device_issue_pending;
	dma->device_tx_status = dw_edma_device_tx_status;
	dma->device_prep_slave_sg = dw_edma_device_prep_slave_sg;
	dma->device_prep_dma_cyclic = dw_edma_device_prep_dma_cyclic;
	dma->device_prep_interleaved_dma = dw_edma_device_prep_interleaved_dma;

	dma_set_max_seg_size(dma->dev, U32_MAX);

	/* Register DMA device */
	err = dma_async_device_register(dma);

	return err;
}

static inline void dw_edma_dec_irq_alloc(int *nr_irqs, u32 *alloc, u16 cnt)
{
	if (*nr_irqs && *alloc < cnt) {
		(*alloc)++;
		(*nr_irqs)--;
	}
}

static inline void dw_edma_add_irq_mask(u32 *mask, u32 alloc, u16 cnt)
{
	while (*mask * alloc < cnt)
		(*mask)++;
}

static int dw_edma_irq_request(struct dw_edma_chip *chip,
			       u32 *wr_alloc, u32 *rd_alloc)
{
	struct device *dev = chip->dev;
	struct dw_edma *dw = chip->dw;
	u32 wr_mask = 1;
	u32 rd_mask = 1;
	int i, err = 0;
	u32 ch_cnt;
	int irq;

	ch_cnt = dw->wr_ch_cnt + dw->rd_ch_cnt;

	if (dw->nr_irqs < 1)
		return -EINVAL;

	if (dw->nr_irqs == 1) {
		/* Common IRQ shared among all channels */
		irq = dw->ops->irq_vector(dev, 0);
		err = request_irq(irq, dw_edma_interrupt_common,
				  IRQF_SHARED, dw->name, &dw->irq[0]);
		if (err) {
			dw->nr_irqs = 0;
			return err;
		}

		if (irq_get_msi_desc(irq))
			get_cached_msi_msg(irq, &dw->irq[0].msi);
	} else {
		/* Distribute IRQs equally among all channels */
		int tmp = dw->nr_irqs;

		while (tmp && (*wr_alloc + *rd_alloc) < ch_cnt) {
			dw_edma_dec_irq_alloc(&tmp, wr_alloc, dw->wr_ch_cnt);
			dw_edma_dec_irq_alloc(&tmp, rd_alloc, dw->rd_ch_cnt);
		}

		dw_edma_add_irq_mask(&wr_mask, *wr_alloc, dw->wr_ch_cnt);
		dw_edma_add_irq_mask(&rd_mask, *rd_alloc, dw->rd_ch_cnt);

		for (i = 0; i < (*wr_alloc + *rd_alloc); i++) {
			irq = dw->ops->irq_vector(dev, i);
			err = request_irq(irq,
					  i < *wr_alloc ?
						dw_edma_interrupt_write :
						dw_edma_interrupt_read,
					  IRQF_SHARED, dw->name,
					  &dw->irq[i]);
			if (err) {
				dw->nr_irqs = i;
				return err;
			}

			if (irq_get_msi_desc(irq))
				get_cached_msi_msg(irq, &dw->irq[i].msi);
		}

		dw->nr_irqs = i;
	}

	return err;
}

int dw_edma_probe(struct dw_edma_chip *chip)
{
	struct device *dev;
	struct dw_edma *dw;
	u32 wr_alloc = 0;
	u32 rd_alloc = 0;
	int i, err;

	if (!chip)
		return -EINVAL;

	dev = chip->dev;
	if (!dev)
		return -EINVAL;

	dw = chip->dw;
	if (!dw || !dw->irq || !dw->ops || !dw->ops->irq_vector)
		return -EINVAL;

	raw_spin_lock_init(&dw->lock);

	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt,
			      dw_edma_v0_core_ch_count(dw, EDMA_DIR_WRITE));
	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);

	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt,
			      dw_edma_v0_core_ch_count(dw, EDMA_DIR_READ));
	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);

	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
		return -EINVAL;

	dev_vdbg(dev, "Channels:\twrite=%d, read=%d\n",
		 dw->wr_ch_cnt, dw->rd_ch_cnt);

	/* Allocate channels */
	dw->chan = devm_kcalloc(dev, dw->wr_ch_cnt + dw->rd_ch_cnt,
				sizeof(*dw->chan), GFP_KERNEL);
	if (!dw->chan)
		return -ENOMEM;

	snprintf(dw->name, sizeof(dw->name), "dw-edma-core:%d", chip->id);

	/* Disable eDMA, only to establish the ideal initial conditions */
	dw_edma_v0_core_off(dw);

	/* Request IRQs */
	err = dw_edma_irq_request(chip, &wr_alloc, &rd_alloc);
	if (err)
		return err;

	/* Setup write channels */
	err = dw_edma_channel_setup(chip, true, wr_alloc, rd_alloc);
	if (err)
		goto err_irq_free;

	/* Setup read channels */
	err = dw_edma_channel_setup(chip, false, wr_alloc, rd_alloc);
	if (err)
		goto err_irq_free;

	/* Power management */
	pm_runtime_enable(dev);

	/* Turn debugfs on */
	dw_edma_v0_core_debugfs_on(chip);

	return 0;

err_irq_free:
	for (i = (dw->nr_irqs - 1); i >= 0; i--)
		free_irq(dw->ops->irq_vector(dev, i), &dw->irq[i]);

	dw->nr_irqs = 0;

	return err;
}
EXPORT_SYMBOL_GPL(dw_edma_probe);

int dw_edma_remove(struct dw_edma_chip *chip)
{
	struct dw_edma_chan *chan, *_chan;
	struct device *dev = chip->dev;
	struct dw_edma *dw = chip->dw;
	int i;

	/* Disable eDMA */
	dw_edma_v0_core_off(dw);

	/* Free irqs */
	for (i = (dw->nr_irqs - 1); i >= 0; i--)
		free_irq(dw->ops->irq_vector(dev, i), &dw->irq[i]);

	/* Power management */
	pm_runtime_disable(dev);

	/* Deregister eDMA device */
	dma_async_device_unregister(&dw->wr_edma);
	list_for_each_entry_safe(chan, _chan, &dw->wr_edma.channels,
				 vc.chan.device_node) {
		tasklet_kill(&chan->vc.task);
		list_del(&chan->vc.chan.device_node);
	}

	dma_async_device_unregister(&dw->rd_edma);
	list_for_each_entry_safe(chan, _chan, &dw->rd_edma.channels,
				 vc.chan.device_node) {
		tasklet_kill(&chan->vc.task);
		list_del(&chan->vc.chan.device_node);
	}

	/* Turn debugfs off */
	dw_edma_v0_core_debugfs_off(chip);

	return 0;
}
EXPORT_SYMBOL_GPL(dw_edma_remove);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Synopsys DesignWare eDMA controller core driver");
MODULE_AUTHOR("Gustavo Pimentel <gustavo.pimentel@synopsys.com>");