aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/dma/ioat/dma_v3.c
blob: 3686dddf6bffb6def756cca7016110dae55fd36e (plain) (blame)
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
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2004 - 2009 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * 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.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * BSD LICENSE
 *
 * Copyright(c) 2004-2009 Intel Corporation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *   * Neither the name of Intel Corporation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Support routines for v3+ hardware
 */

#include <linux/pci.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include "registers.h"
#include "hw.h"
#include "dma.h"
#include "dma_v2.h"

/* ioat hardware assumes at least two sources for raid operations */
#define src_cnt_to_sw(x) ((x) + 2)
#define src_cnt_to_hw(x) ((x) - 2)

/* provide a lookup table for setting the source address in the base or
 * extended descriptor of an xor or pq descriptor
 */
static const u8 xor_idx_to_desc __read_mostly = 0xd0;
static const u8 xor_idx_to_field[] __read_mostly = { 1, 4, 5, 6, 7, 0, 1, 2 };
static const u8 pq_idx_to_desc __read_mostly = 0xf8;
static const u8 pq_idx_to_field[] __read_mostly = { 1, 4, 5, 0, 1, 2, 4, 5 };

static dma_addr_t xor_get_src(struct ioat_raw_descriptor *descs[2], int idx)
{
	struct ioat_raw_descriptor *raw = descs[xor_idx_to_desc >> idx & 1];

	return raw->field[xor_idx_to_field[idx]];
}

static void xor_set_src(struct ioat_raw_descriptor *descs[2],
			dma_addr_t addr, u32 offset, int idx)
{
	struct ioat_raw_descriptor *raw = descs[xor_idx_to_desc >> idx & 1];

	raw->field[xor_idx_to_field[idx]] = addr + offset;
}

static dma_addr_t pq_get_src(struct ioat_raw_descriptor *descs[2], int idx)
{
	struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1];

	return raw->field[pq_idx_to_field[idx]];
}

static void pq_set_src(struct ioat_raw_descriptor *descs[2],
		       dma_addr_t addr, u32 offset, u8 coef, int idx)
{
	struct ioat_pq_descriptor *pq = (struct ioat_pq_descriptor *) descs[0];
	struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1];

	raw->field[pq_idx_to_field[idx]] = addr + offset;
	pq->coef[idx] = coef;
}

static void ioat3_dma_unmap(struct ioat2_dma_chan *ioat,
			    struct ioat_ring_ent *desc, int idx)
{
	struct ioat_chan_common *chan = &ioat->base;
	struct pci_dev *pdev = chan->device->pdev;
	size_t len = desc->len;
	size_t offset = len - desc->hw->size;
	struct dma_async_tx_descriptor *tx = &desc->txd;
	enum dma_ctrl_flags flags = tx->flags;

	switch (desc->hw->ctl_f.op) {
	case IOAT_OP_COPY:
		if (!desc->hw->ctl_f.null) /* skip 'interrupt' ops */
			ioat_dma_unmap(chan, flags, len, desc->hw);
		break;
	case IOAT_OP_FILL: {
		struct ioat_fill_descriptor *hw = desc->fill;

		if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP))
			ioat_unmap(pdev, hw->dst_addr - offset, len,
				   PCI_DMA_FROMDEVICE, flags, 1);
		break;
	}
	case IOAT_OP_XOR_VAL:
	case IOAT_OP_XOR: {
		struct ioat_xor_descriptor *xor = desc->xor;
		struct ioat_ring_ent *ext;
		struct ioat_xor_ext_descriptor *xor_ex = NULL;
		int src_cnt = src_cnt_to_sw(xor->ctl_f.src_cnt);
		struct ioat_raw_descriptor *descs[2];
		int i;

		if (src_cnt > 5) {
			ext = ioat2_get_ring_ent(ioat, idx + 1);
			xor_ex = ext->xor_ex;
		}

		if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
			descs[0] = (struct ioat_raw_descriptor *) xor;
			descs[1] = (struct ioat_raw_descriptor *) xor_ex;
			for (i = 0; i < src_cnt; i++) {
				dma_addr_t src = xor_get_src(descs, i);

				ioat_unmap(pdev, src - offset, len,
					   PCI_DMA_TODEVICE, flags, 0);
			}

			/* dest is a source in xor validate operations */
			if (xor->ctl_f.op == IOAT_OP_XOR_VAL) {
				ioat_unmap(pdev, xor->dst_addr - offset, len,
					   PCI_DMA_TODEVICE, flags, 1);
				break;
			}
		}

		if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP))
			ioat_unmap(pdev, xor->dst_addr - offset, len,
				   PCI_DMA_FROMDEVICE, flags, 1);
		break;
	}
	case IOAT_OP_PQ_VAL:
	case IOAT_OP_PQ: {
		struct ioat_pq_descriptor *pq = desc->pq;
		struct ioat_ring_ent *ext;
		struct ioat_pq_ext_descriptor *pq_ex = NULL;
		int src_cnt = src_cnt_to_sw(pq->ctl_f.src_cnt);
		struct ioat_raw_descriptor *descs[2];
		int i;

		if (src_cnt > 3) {
			ext = ioat2_get_ring_ent(ioat, idx + 1);
			pq_ex = ext->pq_ex;
		}

		/* in the 'continue' case don't unmap the dests as sources */
		if (dmaf_p_disabled_continue(flags))
			src_cnt--;
		else if (dmaf_continue(flags))
			src_cnt -= 3;

		if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
			descs[0] = (struct ioat_raw_descriptor *) pq;
			descs[1] = (struct ioat_raw_descriptor *) pq_ex;
			for (i = 0; i < src_cnt; i++) {
				dma_addr_t src = pq_get_src(descs, i);

				ioat_unmap(pdev, src - offset, len,
					   PCI_DMA_TODEVICE, flags, 0);
			}

			/* the dests are sources in pq validate operations */
			if (pq->ctl_f.op == IOAT_OP_XOR_VAL) {
				if (!(flags & DMA_PREP_PQ_DISABLE_P))
					ioat_unmap(pdev, pq->p_addr - offset,
						   len, PCI_DMA_TODEVICE, flags, 0);
				if (!(flags & DMA_PREP_PQ_DISABLE_Q))
					ioat_unmap(pdev, pq->q_addr - offset,
						   len, PCI_DMA_TODEVICE, flags, 0);
				break;
			}
		}

		if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
			if (!(flags & DMA_PREP_PQ_DISABLE_P))
				ioat_unmap(pdev, pq->p_addr - offset, len,
					   PCI_DMA_BIDIRECTIONAL, flags, 1);
			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
				ioat_unmap(pdev, pq->q_addr - offset, len,
					   PCI_DMA_BIDIRECTIONAL, flags, 1);
		}
		break;
	}
	default:
		dev_err(&pdev->dev, "%s: unknown op type: %#x\n",
			__func__, desc->hw->ctl_f.op);
	}
}

static bool desc_has_ext(struct ioat_ring_ent *desc)
{
	struct ioat_dma_descriptor *hw = desc->hw;

	if (hw->ctl_f.op == IOAT_OP_XOR ||
	    hw->ctl_f.op == IOAT_OP_XOR_VAL) {
		struct ioat_xor_descriptor *xor = desc->xor;

		if (src_cnt_to_sw(xor->ctl_f.src_cnt) > 5)
			return true;
	} else if (hw->ctl_f.op == IOAT_OP_PQ ||
		   hw->ctl_f.op == IOAT_OP_PQ_VAL) {
		struct ioat_pq_descriptor *pq = desc->pq;

		if (src_cnt_to_sw(pq->ctl_f.src_cnt) > 3)
			return true;
	}

	return false;
}

/**
 * __cleanup - reclaim used descriptors
 * @ioat: channel (ring) to clean
 *
 * The difference from the dma_v2.c __cleanup() is that this routine
 * handles extended descriptors and dma-unmapping raid operations.
 */
static void __cleanup(struct ioat2_dma_chan *ioat, unsigned long phys_complete)
{
	struct ioat_chan_common *chan = &ioat->base;
	struct ioat_ring_ent *desc;
	bool seen_current = false;
	u16 active;
	int i;

	dev_dbg(to_dev(chan), "%s: head: %#x tail: %#x issued: %#x\n",
		__func__, ioat->head, ioat->tail, ioat->issued);

	active = ioat2_ring_active(ioat);
	for (i = 0; i < active && !seen_current; i++) {
		struct dma_async_tx_descriptor *tx;

		prefetch(ioat2_get_ring_ent(ioat, ioat->tail + i + 1));
		desc = ioat2_get_ring_ent(ioat, ioat->tail + i);
		dump_desc_dbg(ioat, desc);
		tx = &desc->txd;
		if (tx->cookie) {
			chan->completed_cookie = tx->cookie;
			ioat3_dma_unmap(ioat, desc, ioat->tail + i);
			tx->cookie = 0;
			if (tx->callback) {
				tx->callback(tx->callback_param);
				tx->callback = NULL;
			}
		}

		if (tx->phys == phys_complete)
			seen_current = true;

		/* skip extended descriptors */
		if (desc_has_ext(desc)) {
			BUG_ON(i + 1 >= active);
			i++;
		}
	}
	ioat->tail += i;
	BUG_ON(!seen_current); /* no active descs have written a completion? */
	chan->last_completion = phys_complete;
	if (ioat->head == ioat->tail) {
		dev_dbg(to_dev(chan), "%s: cancel completion timeout\n",
			__func__);
		clear_bit(IOAT_COMPLETION_PENDING, &chan->state);
		mod_timer(&chan->timer, jiffies + IDLE_TIMEOUT);
	}
}

static void ioat3_cleanup(struct ioat2_dma_chan *ioat)
{
	struct ioat_chan_common *chan = &ioat->base;
	unsigned long phys_complete;

	prefetch(chan->completion);

	if (!spin_trylock_bh(&chan->cleanup_lock))
		return;

	if (!ioat_cleanup_preamble(chan, &phys_complete)) {
		spin_unlock_bh(&chan->cleanup_lock);
		return;
	}

	if (!spin_trylock_bh(&ioat->ring_lock)) {
		spin_unlock_bh(&chan->cleanup_lock);
		return;
	}

	__cleanup(ioat, phys_complete);

	spin_unlock_bh(&ioat->ring_lock);
	spin_unlock_bh(&chan->cleanup_lock);
}

static void ioat3_cleanup_tasklet(unsigned long data)
{
	struct ioat2_dma_chan *ioat = (void *) data;

	ioat3_cleanup(ioat);
	writew(IOAT_CHANCTRL_RUN | IOAT3_CHANCTRL_COMPL_DCA_EN,
	       ioat->base.reg_base + IOAT_CHANCTRL_OFFSET);
}

static void ioat3_restart_channel(struct ioat2_dma_chan *ioat)
{
	struct ioat_chan_common *chan = &ioat->base;
	unsigned long phys_complete;
	u32 status;

	status = ioat_chansts(chan);
	if (is_ioat_active(status) || is_ioat_idle(status))
		ioat_suspend(chan);
	while (is_ioat_active(status) || is_ioat_idle(status)) {
		status = ioat_chansts(chan);
		cpu_relax();
	}

	if (ioat_cleanup_preamble(chan, &phys_complete))
		__cleanup(ioat, phys_complete);

	__ioat2_restart_chan(ioat);
}

static void ioat3_timer_event(unsigned long data)
{
	struct ioat2_dma_chan *ioat = (void *) data;
	struct ioat_chan_common *chan = &ioat->base;

	spin_lock_bh(&chan->cleanup_lock);
	if (test_bit(IOAT_COMPLETION_PENDING, &chan->state)) {
		unsigned long phys_complete;
		u64 status;

		spin_lock_bh(&ioat->ring_lock);
		status = ioat_chansts(chan);

		/* when halted due to errors check for channel
		 * programming errors before advancing the completion state
		 */
		if (is_ioat_halted(status)) {
			u32 chanerr;

			chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
			BUG_ON(is_ioat_bug(chanerr));
		}

		/* if we haven't made progress and we have already
		 * acknowledged a pending completion once, then be more
		 * forceful with a restart
		 */
		if (ioat_cleanup_preamble(chan, &phys_complete))
			__cleanup(ioat, phys_complete);
		else if (test_bit(IOAT_COMPLETION_ACK, &chan->state))
			ioat3_restart_channel(ioat);
		else {
			set_bit(IOAT_COMPLETION_ACK, &chan->state);
			mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
		}
		spin_unlock_bh(&ioat->ring_lock);
	} else {
		u16 active;

		/* if the ring is idle, empty, and oversized try to step
		 * down the size
		 */
		spin_lock_bh(&ioat->ring_lock);
		active = ioat2_ring_active(ioat);
		if (active == 0 && ioat->alloc_order > ioat_get_alloc_order())
			reshape_ring(ioat, ioat->alloc_order-1);
		spin_unlock_bh(&ioat->ring_lock);

		/* keep shrinking until we get back to our minimum
		 * default size
		 */
		if (ioat->alloc_order > ioat_get_alloc_order())
			mod_timer(&chan->timer, jiffies + IDLE_TIMEOUT);
	}
	spin_unlock_bh(&chan->cleanup_lock);
}

static enum dma_status
ioat3_is_complete(struct dma_chan *c, dma_cookie_t cookie,
		  dma_cookie_t *done, dma_cookie_t *used)
{
	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);

	if (ioat_is_complete(c, cookie, done, used) == DMA_SUCCESS)
		return DMA_SUCCESS;

	ioat3_cleanup(ioat);

	return ioat_is_complete(c, cookie, done, used);
}

static struct dma_async_tx_descriptor *
ioat3_prep_memset_lock(struct dma_chan *c, dma_addr_t dest, int value,
		       size_t len, unsigned long flags)
{
	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
	struct ioat_ring_ent *desc;
	size_t total_len = len;
	struct ioat_fill_descriptor *fill;
	int num_descs;
	u64 src_data = (0x0101010101010101ULL) * (value & 0xff);
	u16 idx;
	int i;

	num_descs = ioat2_xferlen_to_descs(ioat, len);
	if (likely(num_descs) &&
	    ioat2_alloc_and_lock(&idx, ioat, num_descs) == 0)
		/* pass */;
	else
		return NULL;
	for (i = 0; i < num_descs; i++) {
		size_t xfer_size = min_t(size_t, len, 1 << ioat->xfercap_log);

		desc = ioat2_get_ring_ent(ioat, idx + i);
		fill = desc->fill;

		fill->size = xfer_size;
		fill->src_data = src_data;
		fill->dst_addr = dest;
		fill->ctl = 0;
		fill->ctl_f.op = IOAT_OP_FILL;

		len -= xfer_size;
		dest += xfer_size;
		dump_desc_dbg(ioat, desc);
	}

	desc->txd.flags = flags;
	desc->len = total_len;
	fill->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
	fill->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
	fill->ctl_f.compl_write = 1;
	dump_desc_dbg(ioat, desc);

	/* we leave the channel locked to ensure in order submission */
	return &desc->txd;
}

static struct dma_async_tx_descriptor *
__ioat3_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result,
		      dma_addr_t dest, dma_addr_t *src, unsigned int src_cnt,
		      size_t len, unsigned long flags)
{
	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
	struct ioat_ring_ent *compl_desc;
	struct ioat_ring_ent *desc;
	struct ioat_ring_ent *ext;
	size_t total_len = len;
	struct ioat_xor_descriptor *xor;
	struct ioat_xor_ext_descriptor *xor_ex = NULL;
	struct ioat_dma_descriptor *hw;
	u32 offset = 0;
	int num_descs;
	int with_ext;
	int i;
	u16 idx;
	u8 op = result ? IOAT_OP_XOR_VAL : IOAT_OP_XOR;

	BUG_ON(src_cnt < 2);

	num_descs = ioat2_xferlen_to_descs(ioat, len);
	/* we need 2x the number of descriptors to cover greater than 5
	 * sources
	 */
	if (src_cnt > 5) {
		with_ext = 1;
		num_descs *= 2;
	} else
		with_ext = 0;

	/* completion writes from the raid engine may pass completion
	 * writes from the legacy engine, so we need one extra null
	 * (legacy) descriptor to ensure all completion writes arrive in
	 * order.
	 */
	if (likely(num_descs) &&
	    ioat2_alloc_and_lock(&idx, ioat, num_descs+1) == 0)
		/* pass */;
	else
		return NULL;
	for (i = 0; i < num_descs; i += 1 + with_ext) {
		struct ioat_raw_descriptor *descs[2];
		size_t xfer_size = min_t(size_t, len, 1 << ioat->xfercap_log);
		int s;

		desc = ioat2_get_ring_ent(ioat, idx + i);
		xor = desc->xor;

		/* save a branch by unconditionally retrieving the
		 * extended descriptor xor_set_src() knows to not write
		 * to it in the single descriptor case
		 */
		ext = ioat2_get_ring_ent(ioat, idx + i + 1);
		xor_ex = ext->xor_ex;

		descs[0] = (struct ioat_raw_descriptor *) xor;
		descs[1] = (struct ioat_raw_descriptor *) xor_ex;
		for (s = 0; s < src_cnt; s++)
			xor_set_src(descs, src[s], offset, s);
		xor->size = xfer_size;
		xor->dst_addr = dest + offset;
		xor->ctl = 0;
		xor->ctl_f.op = op;
		xor->ctl_f.src_cnt = src_cnt_to_hw(src_cnt);

		len -= xfer_size;
		offset += xfer_size;
		dump_desc_dbg(ioat, desc);
	}

	/* last xor descriptor carries the unmap parameters and fence bit */
	desc->txd.flags = flags;
	desc->len = total_len;
	if (result)
		desc->result = result;
	xor->ctl_f.fence = !!(flags & DMA_PREP_FENCE);

	/* completion descriptor carries interrupt bit */
	compl_desc = ioat2_get_ring_ent(ioat, idx + i);
	compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT;
	hw = compl_desc->hw;
	hw->ctl = 0;
	hw->ctl_f.null = 1;
	hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
	hw->ctl_f.compl_write = 1;
	hw->size = NULL_DESC_BUFFER_SIZE;
	dump_desc_dbg(ioat, compl_desc);

	/* we leave the channel locked to ensure in order submission */
	return &desc->txd;
}

static struct dma_async_tx_descriptor *
ioat3_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
	       unsigned int src_cnt, size_t len, unsigned long flags)
{
	return __ioat3_prep_xor_lock(chan, NULL, dest, src, src_cnt, len, flags);
}

struct dma_async_tx_descriptor *
ioat3_prep_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)
{
	/* the cleanup routine only sets bits on validate failure, it
	 * does not clear bits on validate success... so clear it here
	 */
	*result = 0;

	return __ioat3_prep_xor_lock(chan, result, src[0], &src[1],
				     src_cnt - 1, len, flags);
}

static void
dump_pq_desc_dbg(struct ioat2_dma_chan *ioat, struct ioat_ring_ent *desc, struct ioat_ring_ent *ext)
{
	struct device *dev = to_dev(&ioat->base);
	struct ioat_pq_descriptor *pq = desc->pq;
	struct ioat_pq_ext_descriptor *pq_ex = ext ? ext->pq_ex : NULL;
	struct ioat_raw_descriptor *descs[] = { (void *) pq, (void *) pq_ex };
	int src_cnt = src_cnt_to_sw(pq->ctl_f.src_cnt);
	int i;

	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) flags: %#x"
		" sz: %#x ctl: %#x (op: %d int: %d compl: %d pq: '%s%s' src_cnt: %d)\n",
		desc_id(desc), (unsigned long long) desc->txd.phys,
		(unsigned long long) (pq_ex ? pq_ex->next : pq->next),
		desc->txd.flags, pq->size, pq->ctl, pq->ctl_f.op, pq->ctl_f.int_en,
		pq->ctl_f.compl_write,
		pq->ctl_f.p_disable ? "" : "p", pq->ctl_f.q_disable ? "" : "q",
		pq->ctl_f.src_cnt);
	for (i = 0; i < src_cnt; i++)
		dev_dbg(dev, "\tsrc[%d]: %#llx coef: %#x\n", i,
			(unsigned long long) pq_get_src(descs, i), pq->coef[i]);
	dev_dbg(dev, "\tP: %#llx\n", pq->p_addr);
	dev_dbg(dev, "\tQ: %#llx\n", pq->q_addr);
}

static struct dma_async_tx_descriptor *
__ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
		     const dma_addr_t *dst, const dma_addr_t *src,
		     unsigned int src_cnt, const unsigned char *scf,
		     size_t len, unsigned long flags)
{
	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
	struct ioat_chan_common *chan = &ioat->base;
	struct ioat_ring_ent *compl_desc;
	struct ioat_ring_ent *desc;
	struct ioat_ring_ent *ext;
	size_t total_len = len;
	struct ioat_pq_descriptor *pq;
	struct ioat_pq_ext_descriptor *pq_ex = NULL;
	struct ioat_dma_descriptor *hw;
	u32 offset = 0;
	int num_descs;
	int with_ext;
	int i, s;
	u16 idx;
	u8 op = result ? IOAT_OP_PQ_VAL : IOAT_OP_PQ;

	dev_dbg(to_dev(chan), "%s\n", __func__);
	/* the engine requires at least two sources (we provide
	 * at least 1 implied source in the DMA_PREP_CONTINUE case)
	 */
	BUG_ON(src_cnt + dmaf_continue(flags) < 2);

	num_descs = ioat2_xferlen_to_descs(ioat, len);
	/* we need 2x the number of descriptors to cover greater than 3
	 * sources
	 */
	if (src_cnt > 3 || flags & DMA_PREP_CONTINUE) {
		with_ext = 1;
		num_descs *= 2;
	} else
		with_ext = 0;

	/* completion writes from the raid engine may pass completion
	 * writes from the legacy engine, so we need one extra null
	 * (legacy) descriptor to ensure all completion writes arrive in
	 * order.
	 */
	if (likely(num_descs) &&
	    ioat2_alloc_and_lock(&idx, ioat, num_descs+1) == 0)
		/* pass */;
	else
		return NULL;
	for (i = 0; i < num_descs; i += 1 + with_ext) {
		struct ioat_raw_descriptor *descs[2];
		size_t xfer_size = min_t(size_t, len, 1 << ioat->xfercap_log);

		desc = ioat2_get_ring_ent(ioat, idx + i);
		pq = desc->pq;

		/* save a branch by unconditionally retrieving the
		 * extended descriptor pq_set_src() knows to not write
		 * to it in the single descriptor case
		 */
		ext = ioat2_get_ring_ent(ioat, idx + i + with_ext);
		pq_ex = ext->pq_ex;

		descs[0] = (struct ioat_raw_descriptor *) pq;
		descs[1] = (struct ioat_raw_descriptor *) pq_ex;

		for (s = 0; s < src_cnt; s++)
			pq_set_src(descs, src[s], offset, scf[s], s);

		/* see the comment for dma_maxpq in include/linux/dmaengine.h */
		if (dmaf_p_disabled_continue(flags))
			pq_set_src(descs, dst[1], offset, 1, s++);
		else if (dmaf_continue(flags)) {
			pq_set_src(descs, dst[0], offset, 0, s++);
			pq_set_src(descs, dst[1], offset, 1, s++);
			pq_set_src(descs, dst[1], offset, 0, s++);
		}
		pq->size = xfer_size;
		pq->p_addr = dst[0] + offset;
		pq->q_addr = dst[1] + offset;
		pq->ctl = 0;
		pq->ctl_f.op = op;
		pq->ctl_f.src_cnt = src_cnt_to_hw(s);
		pq->ctl_f.p_disable = !!(flags & DMA_PREP_PQ_DISABLE_P);
		pq->ctl_f.q_disable = !!(flags & DMA_PREP_PQ_DISABLE_Q);

		len -= xfer_size;
		offset += xfer_size;
	}

	/* last pq descriptor carries the unmap parameters and fence bit */
	desc->txd.flags = flags;
	desc->len = total_len;
	if (result)
		desc->result = result;
	pq->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
	dump_pq_desc_dbg(ioat, desc, ext);

	/* completion descriptor carries interrupt bit */
	compl_desc = ioat2_get_ring_ent(ioat, idx + i);
	compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT;
	hw = compl_desc->hw;
	hw->ctl = 0;
	hw->ctl_f.null = 1;
	hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
	hw->ctl_f.compl_write = 1;
	hw->size = NULL_DESC_BUFFER_SIZE;
	dump_desc_dbg(ioat, compl_desc);

	/* we leave the channel locked to ensure in order submission */
	return &desc->txd;
}

static struct dma_async_tx_descriptor *
ioat3_prep_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)
{
	/* handle the single source multiply case from the raid6
	 * recovery path
	 */
	if (unlikely((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1)) {
		dma_addr_t single_source[2];
		unsigned char single_source_coef[2];

		BUG_ON(flags & DMA_PREP_PQ_DISABLE_Q);
		single_source[0] = src[0];
		single_source[1] = src[0];
		single_source_coef[0] = scf[0];
		single_source_coef[1] = 0;

		return __ioat3_prep_pq_lock(chan, NULL, dst, single_source, 2,
					    single_source_coef, len, flags);
	} else
		return __ioat3_prep_pq_lock(chan, NULL, dst, src, src_cnt, scf,
					    len, flags);
}

struct dma_async_tx_descriptor *
ioat3_prep_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)
{
	/* the cleanup routine only sets bits on validate failure, it
	 * does not clear bits on validate success... so clear it here
	 */
	*pqres = 0;

	return __ioat3_prep_pq_lock(chan, pqres, pq, src, src_cnt, scf, len,
				    flags);
}

static struct dma_async_tx_descriptor *
ioat3_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
		 unsigned int src_cnt, size_t len, unsigned long flags)
{
	unsigned char scf[src_cnt];
	dma_addr_t pq[2];

	memset(scf, 0, src_cnt);
	flags |= DMA_PREP_PQ_DISABLE_Q;
	pq[0] = dst;
	pq[1] = ~0;

	return __ioat3_prep_pq_lock(chan, NULL, pq, src, src_cnt, scf, len,
				    flags);
}

struct dma_async_tx_descriptor *
ioat3_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
		     unsigned int src_cnt, size_t len,
		     enum sum_check_flags *result, unsigned long flags)
{
	unsigned char scf[src_cnt];
	dma_addr_t pq[2];

	/* the cleanup routine only sets bits on validate failure, it
	 * does not clear bits on validate success... so clear it here
	 */
	*result = 0;

	memset(scf, 0, src_cnt);
	flags |= DMA_PREP_PQ_DISABLE_Q;
	pq[0] = src[0];
	pq[1] = ~0;

	return __ioat3_prep_pq_lock(chan, result, pq, &src[1], src_cnt - 1, scf,
				    len, flags);
}

static struct dma_async_tx_descriptor *
ioat3_prep_interrupt_lock(struct dma_chan *c, unsigned long flags)
{
	struct ioat2_dma_chan *ioat = to_ioat2_chan(c);
	struct ioat_ring_ent *desc;
	struct ioat_dma_descriptor *hw;
	u16 idx;

	if (ioat2_alloc_and_lock(&idx, ioat, 1) == 0)
		desc = ioat2_get_ring_ent(ioat, idx);
	else
		return NULL;

	hw = desc->hw;
	hw->ctl = 0;
	hw->ctl_f.null = 1;
	hw->ctl_f.int_en = 1;
	hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
	hw->ctl_f.compl_write = 1;
	hw->size = NULL_DESC_BUFFER_SIZE;
	hw->src_addr = 0;
	hw->dst_addr = 0;

	desc->txd.flags = flags;
	desc->len = 1;

	dump_desc_dbg(ioat, desc);

	/* we leave the channel locked to ensure in order submission */
	return &desc->txd;
}

static void __devinit ioat3_dma_test_callback(void *dma_async_param)
{
	struct completion *cmp = dma_async_param;

	complete(cmp);
}

#define IOAT_NUM_SRC_TEST 6 /* must be <= 8 */
static int __devinit ioat_xor_val_self_test(struct ioatdma_device *device)
{
	int i, src_idx;
	struct page *dest;
	struct page *xor_srcs[IOAT_NUM_SRC_TEST];
	struct page *xor_val_srcs[IOAT_NUM_SRC_TEST + 1];
	dma_addr_t dma_srcs[IOAT_NUM_SRC_TEST + 1];
	dma_addr_t dma_addr, dest_dma;
	struct dma_async_tx_descriptor *tx;
	struct dma_chan *dma_chan;
	dma_cookie_t cookie;
	u8 cmp_byte = 0;
	u32 cmp_word;
	u32 xor_val_result;
	int err = 0;
	struct completion cmp;
	unsigned long tmo;
	struct device *dev = &device->pdev->dev;
	struct dma_device *dma = &device->common;

	dev_dbg(dev, "%s\n", __func__);

	if (!dma_has_cap(DMA_XOR, dma->cap_mask))
		return 0;

	for (src_idx = 0; src_idx < IOAT_NUM_SRC_TEST; src_idx++) {
		xor_srcs[src_idx] = alloc_page(GFP_KERNEL);
		if (!xor_srcs[src_idx]) {
			while (src_idx--)
				__free_page(xor_srcs[src_idx]);
			return -ENOMEM;
		}
	}

	dest = alloc_page(GFP_KERNEL);
	if (!dest) {
		while (src_idx--)
			__free_page(xor_srcs[src_idx]);
		return -ENOMEM;
	}

	/* Fill in src buffers */
	for (src_idx = 0; src_idx < IOAT_NUM_SRC_TEST; src_idx++) {
		u8 *ptr = page_address(xor_srcs[src_idx]);
		for (i = 0; i < PAGE_SIZE; i++)
			ptr[i] = (1 << src_idx);
	}

	for (src_idx = 0; src_idx < IOAT_NUM_SRC_TEST; src_idx++)
		cmp_byte ^= (u8) (1 << src_idx);

	cmp_word = (cmp_byte << 24) | (cmp_byte << 16) |
			(cmp_byte << 8) | cmp_byte;

	memset(page_address(dest), 0, PAGE_SIZE);

	dma_chan = container_of(dma->channels.next, struct dma_chan,
				device_node);
	if (dma->device_alloc_chan_resources(dma_chan) < 1) {
		err = -ENODEV;
		goto out;
	}

	/* test xor */
	dest_dma = dma_map_page(dev, dest, 0, PAGE_SIZE, DMA_FROM_DEVICE);
	for (i = 0; i < IOAT_NUM_SRC_TEST; i++)
		dma_srcs[i] = dma_map_page(dev, xor_srcs[i], 0, PAGE_SIZE,
					   DMA_TO_DEVICE);
	tx = dma->device_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
				      IOAT_NUM_SRC_TEST, PAGE_SIZE,
				      DMA_PREP_INTERRUPT);

	if (!tx) {
		dev_err(dev, "Self-test xor prep failed\n");
		err = -ENODEV;
		goto free_resources;
	}

	async_tx_ack(tx);
	init_completion(&cmp);
	tx->callback = ioat3_dma_test_callback;
	tx->callback_param = &cmp;
	cookie = tx->tx_submit(tx);
	if (cookie < 0) {
		dev_err(dev, "Self-test xor setup failed\n");
		err = -ENODEV;
		goto free_resources;
	}
	dma->device_issue_pending(dma_chan);

	tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));

	if (dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
		dev_err(dev, "Self-test xor timed out\n");
		err = -ENODEV;
		goto free_resources;
	}

	dma_sync_single_for_cpu(dev, dest_dma, PAGE_SIZE, DMA_FROM_DEVICE);
	for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) {
		u32 *ptr = page_address(dest);
		if (ptr[i] != cmp_word) {
			dev_err(dev, "Self-test xor failed compare\n");
			err = -ENODEV;
			goto free_resources;
		}
	}
	dma_sync_single_for_device(dev, dest_dma, PAGE_SIZE, DMA_TO_DEVICE);

	/* skip validate if the capability is not present */
	if (!dma_has_cap(DMA_XOR_VAL, dma_chan->device->cap_mask))
		goto free_resources;

	/* validate the sources with the destintation page */
	for (i = 0; i < IOAT_NUM_SRC_TEST; i++)
		xor_val_srcs[i] = xor_srcs[i];
	xor_val_srcs[i] = dest;

	xor_val_result = 1;

	for (i = 0; i < IOAT_NUM_SRC_TEST + 1; i++)
		dma_srcs[i] = dma_map_page(dev, xor_val_srcs[i], 0, PAGE_SIZE,
					   DMA_TO_DEVICE);
	tx = dma->device_prep_dma_xor_val(dma_chan, dma_srcs,
					  IOAT_NUM_SRC_TEST + 1, PAGE_SIZE,
					  &xor_val_result, DMA_PREP_INTERRUPT);
	if (!tx) {
		dev_err(dev, "Self-test zero prep failed\n");
		err = -ENODEV;
		goto free_resources;
	}

	async_tx_ack(tx);
	init_completion(&cmp);
	tx->callback = ioat3_dma_test_callback;
	tx->callback_param = &cmp;
	cookie = tx->tx_submit(tx);
	if (cookie < 0) {
		dev_err(dev, "Self-test zero setup failed\n");
		err = -ENODEV;
		goto free_resources;
	}
	dma->device_issue_pending(dma_chan);

	tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));

	if (dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
		dev_err(dev, "Self-test validate timed out\n");
		err = -ENODEV;
		goto free_resources;
	}

	if (xor_val_result != 0) {
		dev_err(dev, "Self-test validate failed compare\n");
		err = -ENODEV;
		goto free_resources;
	}

	/* skip memset if the capability is not present */
	if (!dma_has_cap(DMA_MEMSET, dma_chan->device->cap_mask))
		goto free_resources;

	/* test memset */
	dma_addr = dma_map_page(dev, dest, 0,
			PAGE_SIZE, DMA_FROM_DEVICE);
	tx = dma->device_prep_dma_memset(dma_chan, dma_addr, 0, PAGE_SIZE,
					 DMA_PREP_INTERRUPT);
	if (!tx) {
		dev_err(dev, "Self-test memset prep failed\n");
		err = -ENODEV;
		goto free_resources;
	}

	async_tx_ack(tx);
	init_completion(&cmp);
	tx->callback = ioat3_dma_test_callback;
	tx->callback_param = &cmp;
	cookie = tx->tx_submit(tx);
	if (cookie < 0) {
		dev_err(dev, "Self-test memset setup failed\n");
		err = -ENODEV;
		goto free_resources;
	}
	dma->device_issue_pending(dma_chan);

	tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));

	if (dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
		dev_err(dev, "Self-test memset timed out\n");
		err = -ENODEV;
		goto free_resources;
	}

	for (i = 0; i < PAGE_SIZE/sizeof(u32); i++) {
		u32 *ptr = page_address(dest);
		if (ptr[i]) {
			dev_err(dev, "Self-test memset failed compare\n");
			err = -ENODEV;
			goto free_resources;
		}
	}

	/* test for non-zero parity sum */
	xor_val_result = 0;
	for (i = 0; i < IOAT_NUM_SRC_TEST + 1; i++)
		dma_srcs[i] = dma_map_page(dev, xor_val_srcs[i], 0, PAGE_SIZE,
					   DMA_TO_DEVICE);
	tx = dma->device_prep_dma_xor_val(dma_chan, dma_srcs,
					  IOAT_NUM_SRC_TEST + 1, PAGE_SIZE,
					  &xor_val_result, DMA_PREP_INTERRUPT);
	if (!tx) {
		dev_err(dev, "Self-test 2nd zero prep failed\n");
		err = -ENODEV;
		goto free_resources;
	}

	async_tx_ack(tx);
	init_completion(&cmp);
	tx->callback = ioat3_dma_test_callback;
	tx->callback_param = &cmp;
	cookie = tx->tx_submit(tx);
	if (cookie < 0) {
		dev_err(dev, "Self-test  2nd zero setup failed\n");
		err = -ENODEV;
		goto free_resources;
	}
	dma->device_issue_pending(dma_chan);

	tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));

	if (dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
		dev_err(dev, "Self-test 2nd validate timed out\n");
		err = -ENODEV;
		goto free_resources;
	}

	if (xor_val_result != SUM_CHECK_P_RESULT) {
		dev_err(dev, "Self-test validate failed compare\n");
		err = -ENODEV;
		goto free_resources;
	}

free_resources:
	dma->device_free_chan_resources(dma_chan);
out:
	src_idx = IOAT_NUM_SRC_TEST;
	while (src_idx--)
		__free_page(xor_srcs[src_idx]);
	__free_page(dest);
	return err;
}

static int __devinit ioat3_dma_self_test(struct ioatdma_device *device)
{
	int rc = ioat_dma_self_test(device);

	if (rc)
		return rc;

	rc = ioat_xor_val_self_test(device);
	if (rc)
		return rc;

	return 0;
}

int __devinit ioat3_dma_probe(struct ioatdma_device *device, int dca)
{
	struct pci_dev *pdev = device->pdev;
	struct dma_device *dma;
	struct dma_chan *c;
	struct ioat_chan_common *chan;
	bool is_raid_device = false;
	int err;
	u16 dev_id;
	u32 cap;

	device->enumerate_channels = ioat2_enumerate_channels;
	device->self_test = ioat3_dma_self_test;
	dma = &device->common;
	dma->device_prep_dma_memcpy = ioat2_dma_prep_memcpy_lock;
	dma->device_issue_pending = ioat2_issue_pending;
	dma->device_alloc_chan_resources = ioat2_alloc_chan_resources;
	dma->device_free_chan_resources = ioat2_free_chan_resources;

	dma_cap_set(DMA_INTERRUPT, dma->cap_mask);
	dma->device_prep_dma_interrupt = ioat3_prep_interrupt_lock;

	cap = readl(device->reg_base + IOAT_DMA_CAP_OFFSET);
	if (cap & IOAT_CAP_XOR) {
		is_raid_device = true;
		dma->max_xor = 8;
		dma->xor_align = 2;

		dma_cap_set(DMA_XOR, dma->cap_mask);
		dma->device_prep_dma_xor = ioat3_prep_xor;

		dma_cap_set(DMA_XOR_VAL, dma->cap_mask);
		dma->device_prep_dma_xor_val = ioat3_prep_xor_val;
	}
	if (cap & IOAT_CAP_PQ) {
		is_raid_device = true;
		dma_set_maxpq(dma, 8, 0);
		dma->pq_align = 2;

		dma_cap_set(DMA_PQ, dma->cap_mask);
		dma->device_prep_dma_pq = ioat3_prep_pq;

		dma_cap_set(DMA_PQ_VAL, dma->cap_mask);
		dma->device_prep_dma_pq_val = ioat3_prep_pq_val;

		if (!(cap & IOAT_CAP_XOR)) {
			dma->max_xor = 8;
			dma->xor_align = 2;

			dma_cap_set(DMA_XOR, dma->cap_mask);
			dma->device_prep_dma_xor = ioat3_prep_pqxor;

			dma_cap_set(DMA_XOR_VAL, dma->cap_mask);
			dma->device_prep_dma_xor_val = ioat3_prep_pqxor_val;
		}
	}
	if (is_raid_device && (cap & IOAT_CAP_FILL_BLOCK)) {
		dma_cap_set(DMA_MEMSET, dma->cap_mask);
		dma->device_prep_dma_memset = ioat3_prep_memset_lock;
	}


	if (is_raid_device) {
		dma->device_is_tx_complete = ioat3_is_complete;
		device->cleanup_tasklet = ioat3_cleanup_tasklet;
		device->timer_fn = ioat3_timer_event;
	} else {
		dma->device_is_tx_complete = ioat2_is_complete;
		device->cleanup_tasklet = ioat2_cleanup_tasklet;
		device->timer_fn = ioat2_timer_event;
	}

	/* -= IOAT ver.3 workarounds =- */
	/* Write CHANERRMSK_INT with 3E07h to mask out the errors
	 * that can cause stability issues for IOAT ver.3
	 */
	pci_write_config_dword(pdev, IOAT_PCI_CHANERRMASK_INT_OFFSET, 0x3e07);

	/* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
	 * (workaround for spurious config parity error after restart)
	 */
	pci_read_config_word(pdev, IOAT_PCI_DEVICE_ID_OFFSET, &dev_id);
	if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0)
		pci_write_config_dword(pdev, IOAT_PCI_DMAUNCERRSTS_OFFSET, 0x10);

	err = ioat_probe(device);
	if (err)
		return err;
	ioat_set_tcp_copy_break(262144);

	list_for_each_entry(c, &dma->channels, device_node) {
		chan = to_chan_common(c);
		writel(IOAT_DMA_DCA_ANY_CPU,
		       chan->reg_base + IOAT_DCACTRL_OFFSET);
	}

	err = ioat_register(device);
	if (err)
		return err;

	ioat_kobject_add(device, &ioat2_ktype);

	if (dca)
		device->dca = ioat3_dca_init(pdev, device->reg_base);

	return 0;
}