summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
blob: bfb984b2e00c6079b36334eb5a611a0206fa843a (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
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
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
/******************************************************************************
 *
 * 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) 2017 Intel Deutschland GmbH
 * Copyright(c) 2018 - 2019 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License 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.
 *
 * BSD LICENSE
 *
 * Copyright(c) 2017 Intel Deutschland GmbH
 * Copyright(c) 2018 - 2019 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 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.
 *
 *****************************************************************************/
#include <net/tso.h>
#include <linux/tcp.h>

#include "iwl-debug.h"
#include "iwl-csr.h"
#include "iwl-io.h"
#include "internal.h"
#include "fw/api/tx.h"

 /*
 * iwl_pcie_gen2_tx_stop - Stop all Tx DMA channels
 */
void iwl_pcie_gen2_tx_stop(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int txq_id;

	/*
	 * This function can be called before the op_mode disabled the
	 * queues. This happens when we have an rfkill interrupt.
	 * Since we stop Tx altogether - mark the queues as stopped.
	 */
	memset(trans_pcie->queue_stopped, 0, sizeof(trans_pcie->queue_stopped));
	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));

	/* Unmap DMA from host system and free skb's */
	for (txq_id = 0; txq_id < ARRAY_SIZE(trans_pcie->txq); txq_id++) {
		if (!trans_pcie->txq[txq_id])
			continue;
		iwl_pcie_gen2_txq_unmap(trans, txq_id);
	}
}

/*
 * iwl_pcie_txq_update_byte_tbl - Set up entry in Tx byte-count array
 */
static void iwl_pcie_gen2_update_byte_tbl(struct iwl_trans_pcie *trans_pcie,
					  struct iwl_txq *txq, u16 byte_cnt,
					  int num_tbs)
{
	struct iwlagn_scd_bc_tbl *scd_bc_tbl = txq->bc_tbl.addr;
	struct iwl_trans *trans = iwl_trans_pcie_get_trans(trans_pcie);
	struct iwl_gen3_bc_tbl *scd_bc_tbl_gen3 = txq->bc_tbl.addr;
	int idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);
	u8 filled_tfd_size, num_fetch_chunks;
	u16 len = byte_cnt;
	__le16 bc_ent;

	if (WARN(idx >= txq->n_window, "%d >= %d\n", idx, txq->n_window))
		return;

	filled_tfd_size = offsetof(struct iwl_tfh_tfd, tbs) +
				   num_tbs * sizeof(struct iwl_tfh_tb);
	/*
	 * filled_tfd_size contains the number of filled bytes in the TFD.
	 * Dividing it by 64 will give the number of chunks to fetch
	 * to SRAM- 0 for one chunk, 1 for 2 and so on.
	 * If, for example, TFD contains only 3 TBs then 32 bytes
	 * of the TFD are used, and only one chunk of 64 bytes should
	 * be fetched
	 */
	num_fetch_chunks = DIV_ROUND_UP(filled_tfd_size, 64) - 1;

	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
		/* Starting from AX210, the HW expects bytes */
		WARN_ON(trans_pcie->bc_table_dword);
		WARN_ON(len > 0x3FFF);
		bc_ent = cpu_to_le16(len | (num_fetch_chunks << 14));
		scd_bc_tbl_gen3->tfd_offset[idx] = bc_ent;
	} else {
		/* Before AX210, the HW expects DW */
		WARN_ON(!trans_pcie->bc_table_dword);
		len = DIV_ROUND_UP(len, 4);
		WARN_ON(len > 0xFFF);
		bc_ent = cpu_to_le16(len | (num_fetch_chunks << 12));
		scd_bc_tbl->tfd_offset[idx] = bc_ent;
	}
}

/*
 * iwl_pcie_gen2_txq_inc_wr_ptr - Send new write index to hardware
 */
void iwl_pcie_gen2_txq_inc_wr_ptr(struct iwl_trans *trans,
				  struct iwl_txq *txq)
{
	lockdep_assert_held(&txq->lock);

	IWL_DEBUG_TX(trans, "Q:%d WR: 0x%x\n", txq->id, txq->write_ptr);

	/*
	 * if not in power-save mode, uCode will never sleep when we're
	 * trying to tx (during RFKILL, we're not trying to tx).
	 */
	iwl_write32(trans, HBUS_TARG_WRPTR, txq->write_ptr | (txq->id << 16));
}

static u8 iwl_pcie_gen2_get_num_tbs(struct iwl_trans *trans,
				    struct iwl_tfh_tfd *tfd)
{
	return le16_to_cpu(tfd->num_tbs) & 0x1f;
}

static void iwl_pcie_gen2_tfd_unmap(struct iwl_trans *trans,
				    struct iwl_cmd_meta *meta,
				    struct iwl_tfh_tfd *tfd)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int i, num_tbs;

	/* Sanity check on number of chunks */
	num_tbs = iwl_pcie_gen2_get_num_tbs(trans, tfd);

	if (num_tbs > trans_pcie->max_tbs) {
		IWL_ERR(trans, "Too many chunks: %i\n", num_tbs);
		return;
	}

	/* first TB is never freed - it's the bidirectional DMA data */
	for (i = 1; i < num_tbs; i++) {
		if (meta->tbs & BIT(i))
			dma_unmap_page(trans->dev,
				       le64_to_cpu(tfd->tbs[i].addr),
				       le16_to_cpu(tfd->tbs[i].tb_len),
				       DMA_TO_DEVICE);
		else
			dma_unmap_single(trans->dev,
					 le64_to_cpu(tfd->tbs[i].addr),
					 le16_to_cpu(tfd->tbs[i].tb_len),
					 DMA_TO_DEVICE);
	}

	tfd->num_tbs = 0;
}

static void iwl_pcie_gen2_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq)
{
	/* rd_ptr is bounded by TFD_QUEUE_SIZE_MAX and
	 * idx is bounded by n_window
	 */
	int idx = iwl_pcie_get_cmd_index(txq, txq->read_ptr);

	lockdep_assert_held(&txq->lock);

	iwl_pcie_gen2_tfd_unmap(trans, &txq->entries[idx].meta,
				iwl_pcie_get_tfd(trans, txq, idx));

	/* free SKB */
	if (txq->entries) {
		struct sk_buff *skb;

		skb = txq->entries[idx].skb;

		/* Can be called from irqs-disabled context
		 * If skb is not NULL, it means that the whole queue is being
		 * freed and that the queue is not empty - free the skb
		 */
		if (skb) {
			iwl_op_mode_free_skb(trans->op_mode, skb);
			txq->entries[idx].skb = NULL;
		}
	}
}

static int iwl_pcie_gen2_set_tb(struct iwl_trans *trans,
				struct iwl_tfh_tfd *tfd, dma_addr_t addr,
				u16 len)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int idx = iwl_pcie_gen2_get_num_tbs(trans, tfd);
	struct iwl_tfh_tb *tb;

	/*
	 * Only WARN here so we know about the issue, but we mess up our
	 * unmap path because not every place currently checks for errors
	 * returned from this function - it can only return an error if
	 * there's no more space, and so when we know there is enough we
	 * don't always check ...
	 */
	WARN(iwl_pcie_crosses_4g_boundary(addr, len),
	     "possible DMA problem with iova:0x%llx, len:%d\n",
	     (unsigned long long)addr, len);

	if (WARN_ON(idx >= IWL_TFH_NUM_TBS))
		return -EINVAL;
	tb = &tfd->tbs[idx];

	/* Each TFD can point to a maximum max_tbs Tx buffers */
	if (le16_to_cpu(tfd->num_tbs) >= trans_pcie->max_tbs) {
		IWL_ERR(trans, "Error can not send more than %d chunks\n",
			trans_pcie->max_tbs);
		return -EINVAL;
	}

	put_unaligned_le64(addr, &tb->addr);
	tb->tb_len = cpu_to_le16(len);

	tfd->num_tbs = cpu_to_le16(idx + 1);

	return idx;
}

static struct page *get_workaround_page(struct iwl_trans *trans,
					struct sk_buff *skb)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct page **page_ptr;
	struct page *ret;

	page_ptr = (void *)((u8 *)skb->cb + trans_pcie->page_offs);

	ret = alloc_page(GFP_ATOMIC);
	if (!ret)
		return NULL;

	/* set the chaining pointer to the previous page if there */
	*(void **)(page_address(ret) + PAGE_SIZE - sizeof(void *)) = *page_ptr;
	*page_ptr = ret;

	return ret;
}

/*
 * Add a TB and if needed apply the FH HW bug workaround;
 * meta != NULL indicates that it's a page mapping and we
 * need to dma_unmap_page() and set the meta->tbs bit in
 * this case.
 */
static int iwl_pcie_gen2_set_tb_with_wa(struct iwl_trans *trans,
					struct sk_buff *skb,
					struct iwl_tfh_tfd *tfd,
					dma_addr_t phys, void *virt,
					u16 len, struct iwl_cmd_meta *meta)
{
	dma_addr_t oldphys = phys;
	struct page *page;
	int ret;

	if (unlikely(dma_mapping_error(trans->dev, phys)))
		return -ENOMEM;

	if (likely(!iwl_pcie_crosses_4g_boundary(phys, len))) {
		ret = iwl_pcie_gen2_set_tb(trans, tfd, phys, len);

		if (ret < 0)
			goto unmap;

		if (meta)
			meta->tbs |= BIT(ret);

		ret = 0;
		goto trace;
	}

	/*
	 * Work around a hardware bug. If (as expressed in the
	 * condition above) the TB ends on a 32-bit boundary,
	 * then the next TB may be accessed with the wrong
	 * address.
	 * To work around it, copy the data elsewhere and make
	 * a new mapping for it so the device will not fail.
	 */

	if (WARN_ON(len > PAGE_SIZE - sizeof(void *))) {
		ret = -ENOBUFS;
		goto unmap;
	}

	page = get_workaround_page(trans, skb);
	if (!page) {
		ret = -ENOMEM;
		goto unmap;
	}

	memcpy(page_address(page), virt, len);

	phys = dma_map_single(trans->dev, page_address(page), len,
			      DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(trans->dev, phys)))
		return -ENOMEM;
	ret = iwl_pcie_gen2_set_tb(trans, tfd, phys, len);
	if (ret < 0) {
		/* unmap the new allocation as single */
		oldphys = phys;
		meta = NULL;
		goto unmap;
	}
	IWL_WARN(trans,
		 "TB bug workaround: copied %d bytes from 0x%llx to 0x%llx\n",
		 len, (unsigned long long)oldphys, (unsigned long long)phys);

	ret = 0;
unmap:
	if (meta)
		dma_unmap_page(trans->dev, oldphys, len, DMA_TO_DEVICE);
	else
		dma_unmap_single(trans->dev, oldphys, len, DMA_TO_DEVICE);
trace:
	trace_iwlwifi_dev_tx_tb(trans->dev, skb, virt, phys, len);

	return ret;
}

static int iwl_pcie_gen2_build_amsdu(struct iwl_trans *trans,
				     struct sk_buff *skb,
				     struct iwl_tfh_tfd *tfd, int start_len,
				     u8 hdr_len,
				     struct iwl_device_tx_cmd *dev_cmd)
{
#ifdef CONFIG_INET
	struct iwl_tx_cmd_gen2 *tx_cmd = (void *)dev_cmd->payload;
	struct ieee80211_hdr *hdr = (void *)skb->data;
	unsigned int snap_ip_tcp_hdrlen, ip_hdrlen, total_len, hdr_room;
	unsigned int mss = skb_shinfo(skb)->gso_size;
	u16 length, amsdu_pad;
	u8 *start_hdr;
	struct iwl_tso_hdr_page *hdr_page;
	struct tso_t tso;

	trace_iwlwifi_dev_tx(trans->dev, skb, tfd, sizeof(*tfd),
			     &dev_cmd->hdr, start_len, 0);

	ip_hdrlen = skb_transport_header(skb) - skb_network_header(skb);
	snap_ip_tcp_hdrlen = 8 + ip_hdrlen + tcp_hdrlen(skb);
	total_len = skb->len - snap_ip_tcp_hdrlen - hdr_len;
	amsdu_pad = 0;

	/* total amount of header we may need for this A-MSDU */
	hdr_room = DIV_ROUND_UP(total_len, mss) *
		(3 + snap_ip_tcp_hdrlen + sizeof(struct ethhdr));

	/* Our device supports 9 segments at most, it will fit in 1 page */
	hdr_page = get_page_hdr(trans, hdr_room, skb);
	if (!hdr_page)
		return -ENOMEM;

	start_hdr = hdr_page->pos;

	/*
	 * Pull the ieee80211 header to be able to use TSO core,
	 * we will restore it for the tx_status flow.
	 */
	skb_pull(skb, hdr_len);

	/*
	 * Remove the length of all the headers that we don't actually
	 * have in the MPDU by themselves, but that we duplicate into
	 * all the different MSDUs inside the A-MSDU.
	 */
	le16_add_cpu(&tx_cmd->len, -snap_ip_tcp_hdrlen);

	tso_start(skb, &tso);

	while (total_len) {
		/* this is the data left for this subframe */
		unsigned int data_left = min_t(unsigned int, mss, total_len);
		struct sk_buff *csum_skb = NULL;
		unsigned int tb_len;
		dma_addr_t tb_phys;
		u8 *subf_hdrs_start = hdr_page->pos;

		total_len -= data_left;

		memset(hdr_page->pos, 0, amsdu_pad);
		hdr_page->pos += amsdu_pad;
		amsdu_pad = (4 - (sizeof(struct ethhdr) + snap_ip_tcp_hdrlen +
				  data_left)) & 0x3;
		ether_addr_copy(hdr_page->pos, ieee80211_get_DA(hdr));
		hdr_page->pos += ETH_ALEN;
		ether_addr_copy(hdr_page->pos, ieee80211_get_SA(hdr));
		hdr_page->pos += ETH_ALEN;

		length = snap_ip_tcp_hdrlen + data_left;
		*((__be16 *)hdr_page->pos) = cpu_to_be16(length);
		hdr_page->pos += sizeof(length);

		/*
		 * This will copy the SNAP as well which will be considered
		 * as MAC header.
		 */
		tso_build_hdr(skb, hdr_page->pos, &tso, data_left, !total_len);

		hdr_page->pos += snap_ip_tcp_hdrlen;

		tb_len = hdr_page->pos - start_hdr;
		tb_phys = dma_map_single(trans->dev, start_hdr,
					 tb_len, DMA_TO_DEVICE);
		if (unlikely(dma_mapping_error(trans->dev, tb_phys))) {
			dev_kfree_skb(csum_skb);
			goto out_err;
		}
		/*
		 * No need for _with_wa, this is from the TSO page and
		 * we leave some space at the end of it so can't hit
		 * the buggy scenario.
		 */
		iwl_pcie_gen2_set_tb(trans, tfd, tb_phys, tb_len);
		trace_iwlwifi_dev_tx_tb(trans->dev, skb, start_hdr,
					tb_phys, tb_len);
		/* add this subframe's headers' length to the tx_cmd */
		le16_add_cpu(&tx_cmd->len, hdr_page->pos - subf_hdrs_start);

		/* prepare the start_hdr for the next subframe */
		start_hdr = hdr_page->pos;

		/* put the payload */
		while (data_left) {
			int ret;

			tb_len = min_t(unsigned int, tso.size, data_left);
			tb_phys = dma_map_single(trans->dev, tso.data,
						 tb_len, DMA_TO_DEVICE);
			ret = iwl_pcie_gen2_set_tb_with_wa(trans, skb, tfd,
							   tb_phys, tso.data,
							   tb_len, NULL);
			if (ret) {
				dev_kfree_skb(csum_skb);
				goto out_err;
			}

			data_left -= tb_len;
			tso_build_data(skb, &tso, tb_len);
		}
	}

	/* re -add the WiFi header */
	skb_push(skb, hdr_len);

	return 0;

out_err:
#endif
	return -EINVAL;
}

static struct
iwl_tfh_tfd *iwl_pcie_gen2_build_tx_amsdu(struct iwl_trans *trans,
					  struct iwl_txq *txq,
					  struct iwl_device_tx_cmd *dev_cmd,
					  struct sk_buff *skb,
					  struct iwl_cmd_meta *out_meta,
					  int hdr_len,
					  int tx_cmd_len)
{
	int idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);
	struct iwl_tfh_tfd *tfd = iwl_pcie_get_tfd(trans, txq, idx);
	dma_addr_t tb_phys;
	int len;
	void *tb1_addr;

	tb_phys = iwl_pcie_get_first_tb_dma(txq, idx);

	/*
	 * No need for _with_wa, the first TB allocation is aligned up
	 * to a 64-byte boundary and thus can't be at the end or cross
	 * a page boundary (much less a 2^32 boundary).
	 */
	iwl_pcie_gen2_set_tb(trans, tfd, tb_phys, IWL_FIRST_TB_SIZE);

	/*
	 * The second TB (tb1) points to the remainder of the TX command
	 * and the 802.11 header - dword aligned size
	 * (This calculation modifies the TX command, so do it before the
	 * setup of the first TB)
	 */
	len = tx_cmd_len + sizeof(struct iwl_cmd_header) + hdr_len -
	      IWL_FIRST_TB_SIZE;

	/* do not align A-MSDU to dword as the subframe header aligns it */

	/* map the data for TB1 */
	tb1_addr = ((u8 *)&dev_cmd->hdr) + IWL_FIRST_TB_SIZE;
	tb_phys = dma_map_single(trans->dev, tb1_addr, len, DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(trans->dev, tb_phys)))
		goto out_err;
	/*
	 * No need for _with_wa(), we ensure (via alignment) that the data
	 * here can never cross or end at a page boundary.
	 */
	iwl_pcie_gen2_set_tb(trans, tfd, tb_phys, len);

	if (iwl_pcie_gen2_build_amsdu(trans, skb, tfd,
				      len + IWL_FIRST_TB_SIZE,
				      hdr_len, dev_cmd))
		goto out_err;

	/* building the A-MSDU might have changed this data, memcpy it now */
	memcpy(&txq->first_tb_bufs[idx], dev_cmd, IWL_FIRST_TB_SIZE);
	return tfd;

out_err:
	iwl_pcie_gen2_tfd_unmap(trans, out_meta, tfd);
	return NULL;
}

static int iwl_pcie_gen2_tx_add_frags(struct iwl_trans *trans,
				      struct sk_buff *skb,
				      struct iwl_tfh_tfd *tfd,
				      struct iwl_cmd_meta *out_meta)
{
	int i;

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
		dma_addr_t tb_phys;
		unsigned int fragsz = skb_frag_size(frag);
		int ret;

		if (!fragsz)
			continue;

		tb_phys = skb_frag_dma_map(trans->dev, frag, 0,
					   fragsz, DMA_TO_DEVICE);
		ret = iwl_pcie_gen2_set_tb_with_wa(trans, skb, tfd, tb_phys,
						   skb_frag_address(frag),
						   fragsz, out_meta);
		if (ret)
			return ret;
	}

	return 0;
}

static struct
iwl_tfh_tfd *iwl_pcie_gen2_build_tx(struct iwl_trans *trans,
				    struct iwl_txq *txq,
				    struct iwl_device_tx_cmd *dev_cmd,
				    struct sk_buff *skb,
				    struct iwl_cmd_meta *out_meta,
				    int hdr_len,
				    int tx_cmd_len,
				    bool pad)
{
	int idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);
	struct iwl_tfh_tfd *tfd = iwl_pcie_get_tfd(trans, txq, idx);
	dma_addr_t tb_phys;
	int len, tb1_len, tb2_len;
	void *tb1_addr;
	struct sk_buff *frag;

	tb_phys = iwl_pcie_get_first_tb_dma(txq, idx);

	/* The first TB points to bi-directional DMA data */
	memcpy(&txq->first_tb_bufs[idx], dev_cmd, IWL_FIRST_TB_SIZE);

	/*
	 * No need for _with_wa, the first TB allocation is aligned up
	 * to a 64-byte boundary and thus can't be at the end or cross
	 * a page boundary (much less a 2^32 boundary).
	 */
	iwl_pcie_gen2_set_tb(trans, tfd, tb_phys, IWL_FIRST_TB_SIZE);

	/*
	 * The second TB (tb1) points to the remainder of the TX command
	 * and the 802.11 header - dword aligned size
	 * (This calculation modifies the TX command, so do it before the
	 * setup of the first TB)
	 */
	len = tx_cmd_len + sizeof(struct iwl_cmd_header) + hdr_len -
	      IWL_FIRST_TB_SIZE;

	if (pad)
		tb1_len = ALIGN(len, 4);
	else
		tb1_len = len;

	/* map the data for TB1 */
	tb1_addr = ((u8 *)&dev_cmd->hdr) + IWL_FIRST_TB_SIZE;
	tb_phys = dma_map_single(trans->dev, tb1_addr, tb1_len, DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(trans->dev, tb_phys)))
		goto out_err;
	/*
	 * No need for _with_wa(), we ensure (via alignment) that the data
	 * here can never cross or end at a page boundary.
	 */
	iwl_pcie_gen2_set_tb(trans, tfd, tb_phys, tb1_len);
	trace_iwlwifi_dev_tx(trans->dev, skb, tfd, sizeof(*tfd), &dev_cmd->hdr,
			     IWL_FIRST_TB_SIZE + tb1_len, hdr_len);

	/* set up TFD's third entry to point to remainder of skb's head */
	tb2_len = skb_headlen(skb) - hdr_len;

	if (tb2_len > 0) {
		int ret;

		tb_phys = dma_map_single(trans->dev, skb->data + hdr_len,
					 tb2_len, DMA_TO_DEVICE);
		ret = iwl_pcie_gen2_set_tb_with_wa(trans, skb, tfd, tb_phys,
						   skb->data + hdr_len, tb2_len,
						   NULL);
		if (ret)
			goto out_err;
	}

	if (iwl_pcie_gen2_tx_add_frags(trans, skb, tfd, out_meta))
		goto out_err;

	skb_walk_frags(skb, frag) {
		int ret;

		tb_phys = dma_map_single(trans->dev, frag->data,
					 skb_headlen(frag), DMA_TO_DEVICE);
		ret = iwl_pcie_gen2_set_tb_with_wa(trans, skb, tfd, tb_phys,
						   frag->data,
						   skb_headlen(frag), NULL);
		if (ret)
			goto out_err;
		if (iwl_pcie_gen2_tx_add_frags(trans, frag, tfd, out_meta))
			goto out_err;
	}

	return tfd;

out_err:
	iwl_pcie_gen2_tfd_unmap(trans, out_meta, tfd);
	return NULL;
}

static
struct iwl_tfh_tfd *iwl_pcie_gen2_build_tfd(struct iwl_trans *trans,
					    struct iwl_txq *txq,
					    struct iwl_device_tx_cmd *dev_cmd,
					    struct sk_buff *skb,
					    struct iwl_cmd_meta *out_meta)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	int idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);
	struct iwl_tfh_tfd *tfd = iwl_pcie_get_tfd(trans, txq, idx);
	int len, hdr_len;
	bool amsdu;

	/* There must be data left over for TB1 or this code must be changed */
	BUILD_BUG_ON(sizeof(struct iwl_tx_cmd_gen2) < IWL_FIRST_TB_SIZE);

	memset(tfd, 0, sizeof(*tfd));

	if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_AX210)
		len = sizeof(struct iwl_tx_cmd_gen2);
	else
		len = sizeof(struct iwl_tx_cmd_gen3);

	amsdu = ieee80211_is_data_qos(hdr->frame_control) &&
			(*ieee80211_get_qos_ctl(hdr) &
			 IEEE80211_QOS_CTL_A_MSDU_PRESENT);

	hdr_len = ieee80211_hdrlen(hdr->frame_control);

	/*
	 * Only build A-MSDUs here if doing so by GSO, otherwise it may be
	 * an A-MSDU for other reasons, e.g. NAN or an A-MSDU having been
	 * built in the higher layers already.
	 */
	if (amsdu && skb_shinfo(skb)->gso_size)
		return iwl_pcie_gen2_build_tx_amsdu(trans, txq, dev_cmd, skb,
						    out_meta, hdr_len, len);

	return iwl_pcie_gen2_build_tx(trans, txq, dev_cmd, skb, out_meta,
				      hdr_len, len, !amsdu);
}

int iwl_trans_pcie_gen2_tx(struct iwl_trans *trans, struct sk_buff *skb,
			   struct iwl_device_tx_cmd *dev_cmd, int txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_cmd_meta *out_meta;
	struct iwl_txq *txq = trans_pcie->txq[txq_id];
	u16 cmd_len;
	int idx;
	void *tfd;

	if (WARN_ONCE(!test_bit(txq_id, trans_pcie->queue_used),
		      "TX on unused queue %d\n", txq_id))
		return -EINVAL;

	if (skb_is_nonlinear(skb) &&
	    skb_shinfo(skb)->nr_frags > IWL_PCIE_MAX_FRAGS(trans_pcie) &&
	    __skb_linearize(skb))
		return -ENOMEM;

	spin_lock(&txq->lock);

	if (iwl_queue_space(trans, txq) < txq->high_mark) {
		iwl_stop_queue(trans, txq);

		/* don't put the packet on the ring, if there is no room */
		if (unlikely(iwl_queue_space(trans, txq) < 3)) {
			struct iwl_device_tx_cmd **dev_cmd_ptr;

			dev_cmd_ptr = (void *)((u8 *)skb->cb +
					       trans_pcie->dev_cmd_offs);

			*dev_cmd_ptr = dev_cmd;
			__skb_queue_tail(&txq->overflow_q, skb);
			spin_unlock(&txq->lock);
			return 0;
		}
	}

	idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);

	/* Set up driver data for this TFD */
	txq->entries[idx].skb = skb;
	txq->entries[idx].cmd = dev_cmd;

	dev_cmd->hdr.sequence =
		cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
			    INDEX_TO_SEQ(idx)));

	/* Set up first empty entry in queue's array of Tx/cmd buffers */
	out_meta = &txq->entries[idx].meta;
	out_meta->flags = 0;

	tfd = iwl_pcie_gen2_build_tfd(trans, txq, dev_cmd, skb, out_meta);
	if (!tfd) {
		spin_unlock(&txq->lock);
		return -1;
	}

	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
		struct iwl_tx_cmd_gen3 *tx_cmd_gen3 =
			(void *)dev_cmd->payload;

		cmd_len = le16_to_cpu(tx_cmd_gen3->len);
	} else {
		struct iwl_tx_cmd_gen2 *tx_cmd_gen2 =
			(void *)dev_cmd->payload;

		cmd_len = le16_to_cpu(tx_cmd_gen2->len);
	}

	/* Set up entry for this TFD in Tx byte-count array */
	iwl_pcie_gen2_update_byte_tbl(trans_pcie, txq, cmd_len,
				      iwl_pcie_gen2_get_num_tbs(trans, tfd));

	/* start timer if queue currently empty */
	if (txq->read_ptr == txq->write_ptr && txq->wd_timeout)
		mod_timer(&txq->stuck_timer, jiffies + txq->wd_timeout);

	/* Tell device the write index *just past* this latest filled TFD */
	txq->write_ptr = iwl_queue_inc_wrap(trans, txq->write_ptr);
	iwl_pcie_gen2_txq_inc_wr_ptr(trans, txq);
	/*
	 * At this point the frame is "transmitted" successfully
	 * and we will get a TX status notification eventually.
	 */
	spin_unlock(&txq->lock);
	return 0;
}

/*************** HOST COMMAND QUEUE FUNCTIONS   *****/

/*
 * iwl_pcie_gen2_enqueue_hcmd - enqueue a uCode command
 * @priv: device private data point
 * @cmd: a pointer to the ucode command structure
 *
 * The function returns < 0 values to indicate the operation
 * failed. On success, it returns the index (>= 0) of command in the
 * command queue.
 */
static int iwl_pcie_gen2_enqueue_hcmd(struct iwl_trans *trans,
				      struct iwl_host_cmd *cmd)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_txq *txq = trans_pcie->txq[trans_pcie->cmd_queue];
	struct iwl_device_cmd *out_cmd;
	struct iwl_cmd_meta *out_meta;
	unsigned long flags;
	void *dup_buf = NULL;
	dma_addr_t phys_addr;
	int i, cmd_pos, idx;
	u16 copy_size, cmd_size, tb0_size;
	bool had_nocopy = false;
	u8 group_id = iwl_cmd_groupid(cmd->id);
	const u8 *cmddata[IWL_MAX_CMD_TBS_PER_TFD];
	u16 cmdlen[IWL_MAX_CMD_TBS_PER_TFD];
	struct iwl_tfh_tfd *tfd;

	copy_size = sizeof(struct iwl_cmd_header_wide);
	cmd_size = sizeof(struct iwl_cmd_header_wide);

	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
		cmddata[i] = cmd->data[i];
		cmdlen[i] = cmd->len[i];

		if (!cmd->len[i])
			continue;

		/* need at least IWL_FIRST_TB_SIZE copied */
		if (copy_size < IWL_FIRST_TB_SIZE) {
			int copy = IWL_FIRST_TB_SIZE - copy_size;

			if (copy > cmdlen[i])
				copy = cmdlen[i];
			cmdlen[i] -= copy;
			cmddata[i] += copy;
			copy_size += copy;
		}

		if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) {
			had_nocopy = true;
			if (WARN_ON(cmd->dataflags[i] & IWL_HCMD_DFL_DUP)) {
				idx = -EINVAL;
				goto free_dup_buf;
			}
		} else if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP) {
			/*
			 * This is also a chunk that isn't copied
			 * to the static buffer so set had_nocopy.
			 */
			had_nocopy = true;

			/* only allowed once */
			if (WARN_ON(dup_buf)) {
				idx = -EINVAL;
				goto free_dup_buf;
			}

			dup_buf = kmemdup(cmddata[i], cmdlen[i],
					  GFP_ATOMIC);
			if (!dup_buf)
				return -ENOMEM;
		} else {
			/* NOCOPY must not be followed by normal! */
			if (WARN_ON(had_nocopy)) {
				idx = -EINVAL;
				goto free_dup_buf;
			}
			copy_size += cmdlen[i];
		}
		cmd_size += cmd->len[i];
	}

	/*
	 * If any of the command structures end up being larger than the
	 * TFD_MAX_PAYLOAD_SIZE and they aren't dynamically allocated into
	 * separate TFDs, then we will need to increase the size of the buffers
	 */
	if (WARN(copy_size > TFD_MAX_PAYLOAD_SIZE,
		 "Command %s (%#x) is too large (%d bytes)\n",
		 iwl_get_cmd_string(trans, cmd->id), cmd->id, copy_size)) {
		idx = -EINVAL;
		goto free_dup_buf;
	}

	spin_lock_bh(&txq->lock);

	idx = iwl_pcie_get_cmd_index(txq, txq->write_ptr);
	tfd = iwl_pcie_get_tfd(trans, txq, txq->write_ptr);
	memset(tfd, 0, sizeof(*tfd));

	if (iwl_queue_space(trans, txq) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
		spin_unlock_bh(&txq->lock);

		IWL_ERR(trans, "No space in command queue\n");
		iwl_op_mode_cmd_queue_full(trans->op_mode);
		idx = -ENOSPC;
		goto free_dup_buf;
	}

	out_cmd = txq->entries[idx].cmd;
	out_meta = &txq->entries[idx].meta;

	/* re-initialize to NULL */
	memset(out_meta, 0, sizeof(*out_meta));
	if (cmd->flags & CMD_WANT_SKB)
		out_meta->source = cmd;

	/* set up the header */
	out_cmd->hdr_wide.cmd = iwl_cmd_opcode(cmd->id);
	out_cmd->hdr_wide.group_id = group_id;
	out_cmd->hdr_wide.version = iwl_cmd_version(cmd->id);
	out_cmd->hdr_wide.length =
		cpu_to_le16(cmd_size - sizeof(struct iwl_cmd_header_wide));
	out_cmd->hdr_wide.reserved = 0;
	out_cmd->hdr_wide.sequence =
		cpu_to_le16(QUEUE_TO_SEQ(trans_pcie->cmd_queue) |
					 INDEX_TO_SEQ(txq->write_ptr));

	cmd_pos = sizeof(struct iwl_cmd_header_wide);
	copy_size = sizeof(struct iwl_cmd_header_wide);

	/* and copy the data that needs to be copied */
	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
		int copy;

		if (!cmd->len[i])
			continue;

		/* copy everything if not nocopy/dup */
		if (!(cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY |
					   IWL_HCMD_DFL_DUP))) {
			copy = cmd->len[i];

			memcpy((u8 *)out_cmd + cmd_pos, cmd->data[i], copy);
			cmd_pos += copy;
			copy_size += copy;
			continue;
		}

		/*
		 * Otherwise we need at least IWL_FIRST_TB_SIZE copied
		 * in total (for bi-directional DMA), but copy up to what
		 * we can fit into the payload for debug dump purposes.
		 */
		copy = min_t(int, TFD_MAX_PAYLOAD_SIZE - cmd_pos, cmd->len[i]);

		memcpy((u8 *)out_cmd + cmd_pos, cmd->data[i], copy);
		cmd_pos += copy;

		/* However, treat copy_size the proper way, we need it below */
		if (copy_size < IWL_FIRST_TB_SIZE) {
			copy = IWL_FIRST_TB_SIZE - copy_size;

			if (copy > cmd->len[i])
				copy = cmd->len[i];
			copy_size += copy;
		}
	}

	IWL_DEBUG_HC(trans,
		     "Sending command %s (%.2x.%.2x), seq: 0x%04X, %d bytes at %d[%d]:%d\n",
		     iwl_get_cmd_string(trans, cmd->id), group_id,
		     out_cmd->hdr.cmd, le16_to_cpu(out_cmd->hdr.sequence),
		     cmd_size, txq->write_ptr, idx, trans_pcie->cmd_queue);

	/* start the TFD with the minimum copy bytes */
	tb0_size = min_t(int, copy_size, IWL_FIRST_TB_SIZE);
	memcpy(&txq->first_tb_bufs[idx], out_cmd, tb0_size);
	iwl_pcie_gen2_set_tb(trans, tfd, iwl_pcie_get_first_tb_dma(txq, idx),
			     tb0_size);

	/* map first command fragment, if any remains */
	if (copy_size > tb0_size) {
		phys_addr = dma_map_single(trans->dev,
					   (u8 *)out_cmd + tb0_size,
					   copy_size - tb0_size,
					   DMA_TO_DEVICE);
		if (dma_mapping_error(trans->dev, phys_addr)) {
			idx = -ENOMEM;
			iwl_pcie_gen2_tfd_unmap(trans, out_meta, tfd);
			goto out;
		}
		iwl_pcie_gen2_set_tb(trans, tfd, phys_addr,
				     copy_size - tb0_size);
	}

	/* map the remaining (adjusted) nocopy/dup fragments */
	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
		const void *data = cmddata[i];

		if (!cmdlen[i])
			continue;
		if (!(cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY |
					   IWL_HCMD_DFL_DUP)))
			continue;
		if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP)
			data = dup_buf;
		phys_addr = dma_map_single(trans->dev, (void *)data,
					   cmdlen[i], DMA_TO_DEVICE);
		if (dma_mapping_error(trans->dev, phys_addr)) {
			idx = -ENOMEM;
			iwl_pcie_gen2_tfd_unmap(trans, out_meta, tfd);
			goto out;
		}
		iwl_pcie_gen2_set_tb(trans, tfd, phys_addr, cmdlen[i]);
	}

	BUILD_BUG_ON(IWL_TFH_NUM_TBS > sizeof(out_meta->tbs) * BITS_PER_BYTE);
	out_meta->flags = cmd->flags;
	if (WARN_ON_ONCE(txq->entries[idx].free_buf))
		kzfree(txq->entries[idx].free_buf);
	txq->entries[idx].free_buf = dup_buf;

	trace_iwlwifi_dev_hcmd(trans->dev, cmd, cmd_size, &out_cmd->hdr_wide);

	/* start timer if queue currently empty */
	if (txq->read_ptr == txq->write_ptr && txq->wd_timeout)
		mod_timer(&txq->stuck_timer, jiffies + txq->wd_timeout);

	spin_lock_irqsave(&trans_pcie->reg_lock, flags);
	/* Increment and update queue's write index */
	txq->write_ptr = iwl_queue_inc_wrap(trans, txq->write_ptr);
	iwl_pcie_gen2_txq_inc_wr_ptr(trans, txq);
	spin_unlock_irqrestore(&trans_pcie->reg_lock, flags);

out:
	spin_unlock_bh(&txq->lock);
free_dup_buf:
	if (idx < 0)
		kfree(dup_buf);
	return idx;
}

#define HOST_COMPLETE_TIMEOUT	(2 * HZ)

static int iwl_pcie_gen2_send_hcmd_sync(struct iwl_trans *trans,
					struct iwl_host_cmd *cmd)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	const char *cmd_str = iwl_get_cmd_string(trans, cmd->id);
	struct iwl_txq *txq = trans_pcie->txq[trans_pcie->cmd_queue];
	int cmd_idx;
	int ret;

	IWL_DEBUG_INFO(trans, "Attempting to send sync command %s\n", cmd_str);

	if (WARN(test_and_set_bit(STATUS_SYNC_HCMD_ACTIVE,
				  &trans->status),
		 "Command %s: a command is already active!\n", cmd_str))
		return -EIO;

	IWL_DEBUG_INFO(trans, "Setting HCMD_ACTIVE for command %s\n", cmd_str);

	cmd_idx = iwl_pcie_gen2_enqueue_hcmd(trans, cmd);
	if (cmd_idx < 0) {
		ret = cmd_idx;
		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
		IWL_ERR(trans, "Error sending %s: enqueue_hcmd failed: %d\n",
			cmd_str, ret);
		return ret;
	}

	ret = wait_event_timeout(trans_pcie->wait_command_queue,
				 !test_bit(STATUS_SYNC_HCMD_ACTIVE,
					   &trans->status),
				 HOST_COMPLETE_TIMEOUT);
	if (!ret) {
		IWL_ERR(trans, "Error sending %s: time out after %dms.\n",
			cmd_str, jiffies_to_msecs(HOST_COMPLETE_TIMEOUT));

		IWL_ERR(trans, "Current CMD queue read_ptr %d write_ptr %d\n",
			txq->read_ptr, txq->write_ptr);

		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
		IWL_DEBUG_INFO(trans, "Clearing HCMD_ACTIVE for command %s\n",
			       cmd_str);
		ret = -ETIMEDOUT;

		iwl_trans_pcie_sync_nmi(trans);
		goto cancel;
	}

	if (test_bit(STATUS_FW_ERROR, &trans->status)) {
		IWL_ERR(trans, "FW error in SYNC CMD %s\n", cmd_str);
		dump_stack();
		ret = -EIO;
		goto cancel;
	}

	if (!(cmd->flags & CMD_SEND_IN_RFKILL) &&
	    test_bit(STATUS_RFKILL_OPMODE, &trans->status)) {
		IWL_DEBUG_RF_KILL(trans, "RFKILL in SYNC CMD... no rsp\n");
		ret = -ERFKILL;
		goto cancel;
	}

	if ((cmd->flags & CMD_WANT_SKB) && !cmd->resp_pkt) {
		IWL_ERR(trans, "Error: Response NULL in '%s'\n", cmd_str);
		ret = -EIO;
		goto cancel;
	}

	return 0;

cancel:
	if (cmd->flags & CMD_WANT_SKB) {
		/*
		 * Cancel the CMD_WANT_SKB flag for the cmd in the
		 * TX cmd queue. Otherwise in case the cmd comes
		 * in later, it will possibly set an invalid
		 * address (cmd->meta.source).
		 */
		txq->entries[cmd_idx].meta.flags &= ~CMD_WANT_SKB;
	}

	if (cmd->resp_pkt) {
		iwl_free_resp(cmd);
		cmd->resp_pkt = NULL;
	}

	return ret;
}

int iwl_trans_pcie_gen2_send_hcmd(struct iwl_trans *trans,
				  struct iwl_host_cmd *cmd)
{
	if (!(cmd->flags & CMD_SEND_IN_RFKILL) &&
	    test_bit(STATUS_RFKILL_OPMODE, &trans->status)) {
		IWL_DEBUG_RF_KILL(trans, "Dropping CMD 0x%x: RF KILL\n",
				  cmd->id);
		return -ERFKILL;
	}

	if (cmd->flags & CMD_ASYNC) {
		int ret;

		/* An asynchronous command can not expect an SKB to be set. */
		if (WARN_ON(cmd->flags & CMD_WANT_SKB))
			return -EINVAL;

		ret = iwl_pcie_gen2_enqueue_hcmd(trans, cmd);
		if (ret < 0) {
			IWL_ERR(trans,
				"Error sending %s: enqueue_hcmd failed: %d\n",
				iwl_get_cmd_string(trans, cmd->id), ret);
			return ret;
		}
		return 0;
	}

	return iwl_pcie_gen2_send_hcmd_sync(trans, cmd);
}

/*
 * iwl_pcie_gen2_txq_unmap -  Unmap any remaining DMA mappings and free skb's
 */
void iwl_pcie_gen2_txq_unmap(struct iwl_trans *trans, int txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_txq *txq = trans_pcie->txq[txq_id];

	spin_lock_bh(&txq->lock);
	while (txq->write_ptr != txq->read_ptr) {
		IWL_DEBUG_TX_REPLY(trans, "Q %d Free %d\n",
				   txq_id, txq->read_ptr);

		if (txq_id != trans_pcie->cmd_queue) {
			int idx = iwl_pcie_get_cmd_index(txq, txq->read_ptr);
			struct sk_buff *skb = txq->entries[idx].skb;

			if (WARN_ON_ONCE(!skb))
				continue;

			iwl_pcie_free_tso_page(trans_pcie, skb);
		}
		iwl_pcie_gen2_free_tfd(trans, txq);
		txq->read_ptr = iwl_queue_inc_wrap(trans, txq->read_ptr);
	}

	while (!skb_queue_empty(&txq->overflow_q)) {
		struct sk_buff *skb = __skb_dequeue(&txq->overflow_q);

		iwl_op_mode_free_skb(trans->op_mode, skb);
	}

	spin_unlock_bh(&txq->lock);

	/* just in case - this queue may have been stopped */
	iwl_wake_queue(trans, txq);
}

void iwl_pcie_gen2_txq_free_memory(struct iwl_trans *trans,
				   struct iwl_txq *txq)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct device *dev = trans->dev;

	/* De-alloc circular buffer of TFDs */
	if (txq->tfds) {
		dma_free_coherent(dev,
				  trans_pcie->tfd_size * txq->n_window,
				  txq->tfds, txq->dma_addr);
		dma_free_coherent(dev,
				  sizeof(*txq->first_tb_bufs) * txq->n_window,
				  txq->first_tb_bufs, txq->first_tb_dma);
	}

	kfree(txq->entries);
	iwl_pcie_free_dma_ptr(trans, &txq->bc_tbl);
	kfree(txq);
}

/*
 * iwl_pcie_txq_free - Deallocate DMA queue.
 * @txq: Transmit queue to deallocate.
 *
 * Empty queue by removing and destroying all BD's.
 * Free all buffers.
 * 0-fill, but do not free "txq" descriptor structure.
 */
static void iwl_pcie_gen2_txq_free(struct iwl_trans *trans, int txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_txq *txq = trans_pcie->txq[txq_id];
	int i;

	if (WARN_ON(!txq))
		return;

	iwl_pcie_gen2_txq_unmap(trans, txq_id);

	/* De-alloc array of command/tx buffers */
	if (txq_id == trans_pcie->cmd_queue)
		for (i = 0; i < txq->n_window; i++) {
			kzfree(txq->entries[i].cmd);
			kzfree(txq->entries[i].free_buf);
		}
	del_timer_sync(&txq->stuck_timer);

	iwl_pcie_gen2_txq_free_memory(trans, txq);

	trans_pcie->txq[txq_id] = NULL;

	clear_bit(txq_id, trans_pcie->queue_used);
}

int iwl_trans_pcie_dyn_txq_alloc_dma(struct iwl_trans *trans,
				     struct iwl_txq **intxq, int size,
				     unsigned int timeout)
{
	int ret;

	struct iwl_txq *txq;
	txq = kzalloc(sizeof(*txq), GFP_KERNEL);
	if (!txq)
		return -ENOMEM;
	ret = iwl_pcie_alloc_dma_ptr(trans, &txq->bc_tbl,
				     (trans->trans_cfg->device_family >=
				      IWL_DEVICE_FAMILY_AX210) ?
				     sizeof(struct iwl_gen3_bc_tbl) :
				     sizeof(struct iwlagn_scd_bc_tbl));
	if (ret) {
		IWL_ERR(trans, "Scheduler BC Table allocation failed\n");
		kfree(txq);
		return -ENOMEM;
	}

	ret = iwl_pcie_txq_alloc(trans, txq, size, false);
	if (ret) {
		IWL_ERR(trans, "Tx queue alloc failed\n");
		goto error;
	}
	ret = iwl_pcie_txq_init(trans, txq, size, false);
	if (ret) {
		IWL_ERR(trans, "Tx queue init failed\n");
		goto error;
	}

	txq->wd_timeout = msecs_to_jiffies(timeout);

	*intxq = txq;
	return 0;

error:
	iwl_pcie_gen2_txq_free_memory(trans, txq);
	return ret;
}

int iwl_trans_pcie_txq_alloc_response(struct iwl_trans *trans,
				      struct iwl_txq *txq,
				      struct iwl_host_cmd *hcmd)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_tx_queue_cfg_rsp *rsp;
	int ret, qid;
	u32 wr_ptr;

	if (WARN_ON(iwl_rx_packet_payload_len(hcmd->resp_pkt) !=
		    sizeof(*rsp))) {
		ret = -EINVAL;
		goto error_free_resp;
	}

	rsp = (void *)hcmd->resp_pkt->data;
	qid = le16_to_cpu(rsp->queue_number);
	wr_ptr = le16_to_cpu(rsp->write_pointer);

	if (qid >= ARRAY_SIZE(trans_pcie->txq)) {
		WARN_ONCE(1, "queue index %d unsupported", qid);
		ret = -EIO;
		goto error_free_resp;
	}

	if (test_and_set_bit(qid, trans_pcie->queue_used)) {
		WARN_ONCE(1, "queue %d already used", qid);
		ret = -EIO;
		goto error_free_resp;
	}

	txq->id = qid;
	trans_pcie->txq[qid] = txq;
	wr_ptr &= (trans->trans_cfg->base_params->max_tfd_queue_size - 1);

	/* Place first TFD at index corresponding to start sequence number */
	txq->read_ptr = wr_ptr;
	txq->write_ptr = wr_ptr;

	IWL_DEBUG_TX_QUEUES(trans, "Activate queue %d\n", qid);

	iwl_free_resp(hcmd);
	return qid;

error_free_resp:
	iwl_free_resp(hcmd);
	iwl_pcie_gen2_txq_free_memory(trans, txq);
	return ret;
}

int iwl_trans_pcie_dyn_txq_alloc(struct iwl_trans *trans,
				 __le16 flags, u8 sta_id, u8 tid,
				 int cmd_id, int size,
				 unsigned int timeout)
{
	struct iwl_txq *txq = NULL;
	struct iwl_tx_queue_cfg_cmd cmd = {
		.flags = flags,
		.sta_id = sta_id,
		.tid = tid,
	};
	struct iwl_host_cmd hcmd = {
		.id = cmd_id,
		.len = { sizeof(cmd) },
		.data = { &cmd, },
		.flags = CMD_WANT_SKB,
	};
	int ret;

	ret = iwl_trans_pcie_dyn_txq_alloc_dma(trans, &txq, size, timeout);
	if (ret)
		return ret;

	cmd.tfdq_addr = cpu_to_le64(txq->dma_addr);
	cmd.byte_cnt_addr = cpu_to_le64(txq->bc_tbl.dma);
	cmd.cb_size = cpu_to_le32(TFD_QUEUE_CB_SIZE(size));

	ret = iwl_trans_send_cmd(trans, &hcmd);
	if (ret)
		goto error;

	return iwl_trans_pcie_txq_alloc_response(trans, txq, &hcmd);

error:
	iwl_pcie_gen2_txq_free_memory(trans, txq);
	return ret;
}

void iwl_trans_pcie_dyn_txq_free(struct iwl_trans *trans, int queue)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	/*
	 * Upon HW Rfkill - we stop the device, and then stop the queues
	 * in the op_mode. Just for the sake of the simplicity of the op_mode,
	 * allow the op_mode to call txq_disable after it already called
	 * stop_device.
	 */
	if (!test_and_clear_bit(queue, trans_pcie->queue_used)) {
		WARN_ONCE(test_bit(STATUS_DEVICE_ENABLED, &trans->status),
			  "queue %d not used", queue);
		return;
	}

	iwl_pcie_gen2_txq_unmap(trans, queue);

	IWL_DEBUG_TX_QUEUES(trans, "Deactivate queue %d\n", queue);
}

void iwl_pcie_gen2_tx_free(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int i;

	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));

	/* Free all TX queues */
	for (i = 0; i < ARRAY_SIZE(trans_pcie->txq); i++) {
		if (!trans_pcie->txq[i])
			continue;

		iwl_pcie_gen2_txq_free(trans, i);
	}
}

int iwl_pcie_gen2_tx_init(struct iwl_trans *trans, int txq_id, int queue_size)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_txq *queue;
	int ret;

	/* alloc and init the tx queue */
	if (!trans_pcie->txq[txq_id]) {
		queue = kzalloc(sizeof(*queue), GFP_KERNEL);
		if (!queue) {
			IWL_ERR(trans, "Not enough memory for tx queue\n");
			return -ENOMEM;
		}
		trans_pcie->txq[txq_id] = queue;
		ret = iwl_pcie_txq_alloc(trans, queue, queue_size, true);
		if (ret) {
			IWL_ERR(trans, "Tx %d queue init failed\n", txq_id);
			goto error;
		}
	} else {
		queue = trans_pcie->txq[txq_id];
	}

	ret = iwl_pcie_txq_init(trans, queue, queue_size,
				(txq_id == trans_pcie->cmd_queue));
	if (ret) {
		IWL_ERR(trans, "Tx %d queue alloc failed\n", txq_id);
		goto error;
	}
	trans_pcie->txq[txq_id]->id = txq_id;
	set_bit(txq_id, trans_pcie->queue_used);

	return 0;

error:
	iwl_pcie_gen2_tx_free(trans);
	return ret;
}