summaryrefslogtreecommitdiffstats
path: root/drivers/net/wireless/ath/ath10k/htt_rx.c
blob: 1b7a04366256febc8438e02a01eb979102cb1d39 (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
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
/*
 * Copyright (c) 2005-2011 Atheros Communications Inc.
 * Copyright (c) 2011-2013 Qualcomm Atheros, Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "core.h"
#include "htc.h"
#include "htt.h"
#include "txrx.h"
#include "debug.h"
#include "trace.h"
#include "mac.h"

#include <linux/log2.h>

#define HTT_RX_RING_SIZE HTT_RX_RING_SIZE_MAX
#define HTT_RX_RING_FILL_LEVEL (((HTT_RX_RING_SIZE) / 2) - 1)

/* when under memory pressure rx ring refill may fail and needs a retry */
#define HTT_RX_RING_REFILL_RETRY_MS 50

static int ath10k_htt_rx_get_csum_state(struct sk_buff *skb);
static void ath10k_htt_txrx_compl_task(unsigned long ptr);

static struct sk_buff *
ath10k_htt_rx_find_skb_paddr(struct ath10k *ar, u32 paddr)
{
	struct ath10k_skb_rxcb *rxcb;

	hash_for_each_possible(ar->htt.rx_ring.skb_table, rxcb, hlist, paddr)
		if (rxcb->paddr == paddr)
			return ATH10K_RXCB_SKB(rxcb);

	WARN_ON_ONCE(1);
	return NULL;
}

static void ath10k_htt_rx_ring_free(struct ath10k_htt *htt)
{
	struct sk_buff *skb;
	struct ath10k_skb_rxcb *rxcb;
	struct hlist_node *n;
	int i;

	if (htt->rx_ring.in_ord_rx) {
		hash_for_each_safe(htt->rx_ring.skb_table, i, n, rxcb, hlist) {
			skb = ATH10K_RXCB_SKB(rxcb);
			dma_unmap_single(htt->ar->dev, rxcb->paddr,
					 skb->len + skb_tailroom(skb),
					 DMA_FROM_DEVICE);
			hash_del(&rxcb->hlist);
			dev_kfree_skb_any(skb);
		}
	} else {
		for (i = 0; i < htt->rx_ring.size; i++) {
			skb = htt->rx_ring.netbufs_ring[i];
			if (!skb)
				continue;

			rxcb = ATH10K_SKB_RXCB(skb);
			dma_unmap_single(htt->ar->dev, rxcb->paddr,
					 skb->len + skb_tailroom(skb),
					 DMA_FROM_DEVICE);
			dev_kfree_skb_any(skb);
		}
	}

	htt->rx_ring.fill_cnt = 0;
	hash_init(htt->rx_ring.skb_table);
	memset(htt->rx_ring.netbufs_ring, 0,
	       htt->rx_ring.size * sizeof(htt->rx_ring.netbufs_ring[0]));
}

static int __ath10k_htt_rx_ring_fill_n(struct ath10k_htt *htt, int num)
{
	struct htt_rx_desc *rx_desc;
	struct ath10k_skb_rxcb *rxcb;
	struct sk_buff *skb;
	dma_addr_t paddr;
	int ret = 0, idx;

	/* The Full Rx Reorder firmware has no way of telling the host
	 * implicitly when it copied HTT Rx Ring buffers to MAC Rx Ring.
	 * To keep things simple make sure ring is always half empty. This
	 * guarantees there'll be no replenishment overruns possible.
	 */
	BUILD_BUG_ON(HTT_RX_RING_FILL_LEVEL >= HTT_RX_RING_SIZE / 2);

	idx = __le32_to_cpu(*htt->rx_ring.alloc_idx.vaddr);
	while (num > 0) {
		skb = dev_alloc_skb(HTT_RX_BUF_SIZE + HTT_RX_DESC_ALIGN);
		if (!skb) {
			ret = -ENOMEM;
			goto fail;
		}

		if (!IS_ALIGNED((unsigned long)skb->data, HTT_RX_DESC_ALIGN))
			skb_pull(skb,
				 PTR_ALIGN(skb->data, HTT_RX_DESC_ALIGN) -
				 skb->data);

		/* Clear rx_desc attention word before posting to Rx ring */
		rx_desc = (struct htt_rx_desc *)skb->data;
		rx_desc->attention.flags = __cpu_to_le32(0);

		paddr = dma_map_single(htt->ar->dev, skb->data,
				       skb->len + skb_tailroom(skb),
				       DMA_FROM_DEVICE);

		if (unlikely(dma_mapping_error(htt->ar->dev, paddr))) {
			dev_kfree_skb_any(skb);
			ret = -ENOMEM;
			goto fail;
		}

		rxcb = ATH10K_SKB_RXCB(skb);
		rxcb->paddr = paddr;
		htt->rx_ring.netbufs_ring[idx] = skb;
		htt->rx_ring.paddrs_ring[idx] = __cpu_to_le32(paddr);
		htt->rx_ring.fill_cnt++;

		if (htt->rx_ring.in_ord_rx) {
			hash_add(htt->rx_ring.skb_table,
				 &ATH10K_SKB_RXCB(skb)->hlist,
				 (u32)paddr);
		}

		num--;
		idx++;
		idx &= htt->rx_ring.size_mask;
	}

fail:
	/*
	 * Make sure the rx buffer is updated before available buffer
	 * index to avoid any potential rx ring corruption.
	 */
	mb();
	*htt->rx_ring.alloc_idx.vaddr = __cpu_to_le32(idx);
	return ret;
}

static int ath10k_htt_rx_ring_fill_n(struct ath10k_htt *htt, int num)
{
	lockdep_assert_held(&htt->rx_ring.lock);
	return __ath10k_htt_rx_ring_fill_n(htt, num);
}

static void ath10k_htt_rx_msdu_buff_replenish(struct ath10k_htt *htt)
{
	int ret, num_deficit, num_to_fill;

	/* Refilling the whole RX ring buffer proves to be a bad idea. The
	 * reason is RX may take up significant amount of CPU cycles and starve
	 * other tasks, e.g. TX on an ethernet device while acting as a bridge
	 * with ath10k wlan interface. This ended up with very poor performance
	 * once CPU the host system was overwhelmed with RX on ath10k.
	 *
	 * By limiting the number of refills the replenishing occurs
	 * progressively. This in turns makes use of the fact tasklets are
	 * processed in FIFO order. This means actual RX processing can starve
	 * out refilling. If there's not enough buffers on RX ring FW will not
	 * report RX until it is refilled with enough buffers. This
	 * automatically balances load wrt to CPU power.
	 *
	 * This probably comes at a cost of lower maximum throughput but
	 * improves the average and stability. */
	spin_lock_bh(&htt->rx_ring.lock);
	num_deficit = htt->rx_ring.fill_level - htt->rx_ring.fill_cnt;
	num_to_fill = min(ATH10K_HTT_MAX_NUM_REFILL, num_deficit);
	num_deficit -= num_to_fill;
	ret = ath10k_htt_rx_ring_fill_n(htt, num_to_fill);
	if (ret == -ENOMEM) {
		/*
		 * Failed to fill it to the desired level -
		 * we'll start a timer and try again next time.
		 * As long as enough buffers are left in the ring for
		 * another A-MPDU rx, no special recovery is needed.
		 */
		mod_timer(&htt->rx_ring.refill_retry_timer, jiffies +
			  msecs_to_jiffies(HTT_RX_RING_REFILL_RETRY_MS));
	} else if (num_deficit > 0) {
		tasklet_schedule(&htt->rx_replenish_task);
	}
	spin_unlock_bh(&htt->rx_ring.lock);
}

static void ath10k_htt_rx_ring_refill_retry(unsigned long arg)
{
	struct ath10k_htt *htt = (struct ath10k_htt *)arg;

	ath10k_htt_rx_msdu_buff_replenish(htt);
}

int ath10k_htt_rx_ring_refill(struct ath10k *ar)
{
	struct ath10k_htt *htt = &ar->htt;
	int ret;

	spin_lock_bh(&htt->rx_ring.lock);
	ret = ath10k_htt_rx_ring_fill_n(htt, (htt->rx_ring.fill_level -
					      htt->rx_ring.fill_cnt));
	spin_unlock_bh(&htt->rx_ring.lock);

	if (ret)
		ath10k_htt_rx_ring_free(htt);

	return ret;
}

void ath10k_htt_rx_free(struct ath10k_htt *htt)
{
	del_timer_sync(&htt->rx_ring.refill_retry_timer);
	tasklet_kill(&htt->rx_replenish_task);
	tasklet_kill(&htt->txrx_compl_task);

	skb_queue_purge(&htt->tx_compl_q);
	skb_queue_purge(&htt->rx_compl_q);
	skb_queue_purge(&htt->rx_in_ord_compl_q);

	ath10k_htt_rx_ring_free(htt);

	dma_free_coherent(htt->ar->dev,
			  (htt->rx_ring.size *
			   sizeof(htt->rx_ring.paddrs_ring)),
			  htt->rx_ring.paddrs_ring,
			  htt->rx_ring.base_paddr);

	dma_free_coherent(htt->ar->dev,
			  sizeof(*htt->rx_ring.alloc_idx.vaddr),
			  htt->rx_ring.alloc_idx.vaddr,
			  htt->rx_ring.alloc_idx.paddr);

	kfree(htt->rx_ring.netbufs_ring);
}

static inline struct sk_buff *ath10k_htt_rx_netbuf_pop(struct ath10k_htt *htt)
{
	struct ath10k *ar = htt->ar;
	int idx;
	struct sk_buff *msdu;

	lockdep_assert_held(&htt->rx_ring.lock);

	if (htt->rx_ring.fill_cnt == 0) {
		ath10k_warn(ar, "tried to pop sk_buff from an empty rx ring\n");
		return NULL;
	}

	idx = htt->rx_ring.sw_rd_idx.msdu_payld;
	msdu = htt->rx_ring.netbufs_ring[idx];
	htt->rx_ring.netbufs_ring[idx] = NULL;
	htt->rx_ring.paddrs_ring[idx] = 0;

	idx++;
	idx &= htt->rx_ring.size_mask;
	htt->rx_ring.sw_rd_idx.msdu_payld = idx;
	htt->rx_ring.fill_cnt--;

	dma_unmap_single(htt->ar->dev,
			 ATH10K_SKB_RXCB(msdu)->paddr,
			 msdu->len + skb_tailroom(msdu),
			 DMA_FROM_DEVICE);
	ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt rx netbuf pop: ",
			msdu->data, msdu->len + skb_tailroom(msdu));

	return msdu;
}

/* return: < 0 fatal error, 0 - non chained msdu, 1 chained msdu */
static int ath10k_htt_rx_amsdu_pop(struct ath10k_htt *htt,
				   u8 **fw_desc, int *fw_desc_len,
				   struct sk_buff_head *amsdu)
{
	struct ath10k *ar = htt->ar;
	int msdu_len, msdu_chaining = 0;
	struct sk_buff *msdu;
	struct htt_rx_desc *rx_desc;

	lockdep_assert_held(&htt->rx_ring.lock);

	for (;;) {
		int last_msdu, msdu_len_invalid, msdu_chained;

		msdu = ath10k_htt_rx_netbuf_pop(htt);
		if (!msdu) {
			__skb_queue_purge(amsdu);
			return -ENOENT;
		}

		__skb_queue_tail(amsdu, msdu);

		rx_desc = (struct htt_rx_desc *)msdu->data;

		/* FIXME: we must report msdu payload since this is what caller
		 *        expects now */
		skb_put(msdu, offsetof(struct htt_rx_desc, msdu_payload));
		skb_pull(msdu, offsetof(struct htt_rx_desc, msdu_payload));

		/*
		 * Sanity check - confirm the HW is finished filling in the
		 * rx data.
		 * If the HW and SW are working correctly, then it's guaranteed
		 * that the HW's MAC DMA is done before this point in the SW.
		 * To prevent the case that we handle a stale Rx descriptor,
		 * just assert for now until we have a way to recover.
		 */
		if (!(__le32_to_cpu(rx_desc->attention.flags)
				& RX_ATTENTION_FLAGS_MSDU_DONE)) {
			__skb_queue_purge(amsdu);
			return -EIO;
		}

		/*
		 * Copy the FW rx descriptor for this MSDU from the rx
		 * indication message into the MSDU's netbuf. HL uses the
		 * same rx indication message definition as LL, and simply
		 * appends new info (fields from the HW rx desc, and the
		 * MSDU payload itself). So, the offset into the rx
		 * indication message only has to account for the standard
		 * offset of the per-MSDU FW rx desc info within the
		 * message, and how many bytes of the per-MSDU FW rx desc
		 * info have already been consumed. (And the endianness of
		 * the host, since for a big-endian host, the rx ind
		 * message contents, including the per-MSDU rx desc bytes,
		 * were byteswapped during upload.)
		 */
		if (*fw_desc_len > 0) {
			rx_desc->fw_desc.info0 = **fw_desc;
			/*
			 * The target is expected to only provide the basic
			 * per-MSDU rx descriptors. Just to be sure, verify
			 * that the target has not attached extension data
			 * (e.g. LRO flow ID).
			 */

			/* or more, if there's extension data */
			(*fw_desc)++;
			(*fw_desc_len)--;
		} else {
			/*
			 * When an oversized AMSDU happened, FW will lost
			 * some of MSDU status - in this case, the FW
			 * descriptors provided will be less than the
			 * actual MSDUs inside this MPDU. Mark the FW
			 * descriptors so that it will still deliver to
			 * upper stack, if no CRC error for this MPDU.
			 *
			 * FIX THIS - the FW descriptors are actually for
			 * MSDUs in the end of this A-MSDU instead of the
			 * beginning.
			 */
			rx_desc->fw_desc.info0 = 0;
		}

		msdu_len_invalid = !!(__le32_to_cpu(rx_desc->attention.flags)
					& (RX_ATTENTION_FLAGS_MPDU_LENGTH_ERR |
					   RX_ATTENTION_FLAGS_MSDU_LENGTH_ERR));
		msdu_len = MS(__le32_to_cpu(rx_desc->msdu_start.common.info0),
			      RX_MSDU_START_INFO0_MSDU_LENGTH);
		msdu_chained = rx_desc->frag_info.ring2_more_count;

		if (msdu_len_invalid)
			msdu_len = 0;

		skb_trim(msdu, 0);
		skb_put(msdu, min(msdu_len, HTT_RX_MSDU_SIZE));
		msdu_len -= msdu->len;

		/* Note: Chained buffers do not contain rx descriptor */
		while (msdu_chained--) {
			msdu = ath10k_htt_rx_netbuf_pop(htt);
			if (!msdu) {
				__skb_queue_purge(amsdu);
				return -ENOENT;
			}

			__skb_queue_tail(amsdu, msdu);
			skb_trim(msdu, 0);
			skb_put(msdu, min(msdu_len, HTT_RX_BUF_SIZE));
			msdu_len -= msdu->len;
			msdu_chaining = 1;
		}

		last_msdu = __le32_to_cpu(rx_desc->msdu_end.common.info0) &
				RX_MSDU_END_INFO0_LAST_MSDU;

		trace_ath10k_htt_rx_desc(ar, &rx_desc->attention,
					 sizeof(*rx_desc) - sizeof(u32));

		if (last_msdu)
			break;
	}

	if (skb_queue_empty(amsdu))
		msdu_chaining = -1;

	/*
	 * Don't refill the ring yet.
	 *
	 * First, the elements popped here are still in use - it is not
	 * safe to overwrite them until the matching call to
	 * mpdu_desc_list_next. Second, for efficiency it is preferable to
	 * refill the rx ring with 1 PPDU's worth of rx buffers (something
	 * like 32 x 3 buffers), rather than one MPDU's worth of rx buffers
	 * (something like 3 buffers). Consequently, we'll rely on the txrx
	 * SW to tell us when it is done pulling all the PPDU's rx buffers
	 * out of the rx ring, and then refill it just once.
	 */

	return msdu_chaining;
}

static void ath10k_htt_rx_replenish_task(unsigned long ptr)
{
	struct ath10k_htt *htt = (struct ath10k_htt *)ptr;

	ath10k_htt_rx_msdu_buff_replenish(htt);
}

static struct sk_buff *ath10k_htt_rx_pop_paddr(struct ath10k_htt *htt,
					       u32 paddr)
{
	struct ath10k *ar = htt->ar;
	struct ath10k_skb_rxcb *rxcb;
	struct sk_buff *msdu;

	lockdep_assert_held(&htt->rx_ring.lock);

	msdu = ath10k_htt_rx_find_skb_paddr(ar, paddr);
	if (!msdu)
		return NULL;

	rxcb = ATH10K_SKB_RXCB(msdu);
	hash_del(&rxcb->hlist);
	htt->rx_ring.fill_cnt--;

	dma_unmap_single(htt->ar->dev, rxcb->paddr,
			 msdu->len + skb_tailroom(msdu),
			 DMA_FROM_DEVICE);
	ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt rx netbuf pop: ",
			msdu->data, msdu->len + skb_tailroom(msdu));

	return msdu;
}

static int ath10k_htt_rx_pop_paddr_list(struct ath10k_htt *htt,
					struct htt_rx_in_ord_ind *ev,
					struct sk_buff_head *list)
{
	struct ath10k *ar = htt->ar;
	struct htt_rx_in_ord_msdu_desc *msdu_desc = ev->msdu_descs;
	struct htt_rx_desc *rxd;
	struct sk_buff *msdu;
	int msdu_count;
	bool is_offload;
	u32 paddr;

	lockdep_assert_held(&htt->rx_ring.lock);

	msdu_count = __le16_to_cpu(ev->msdu_count);
	is_offload = !!(ev->info & HTT_RX_IN_ORD_IND_INFO_OFFLOAD_MASK);

	while (msdu_count--) {
		paddr = __le32_to_cpu(msdu_desc->msdu_paddr);

		msdu = ath10k_htt_rx_pop_paddr(htt, paddr);
		if (!msdu) {
			__skb_queue_purge(list);
			return -ENOENT;
		}

		__skb_queue_tail(list, msdu);

		if (!is_offload) {
			rxd = (void *)msdu->data;

			trace_ath10k_htt_rx_desc(ar, rxd, sizeof(*rxd));

			skb_put(msdu, sizeof(*rxd));
			skb_pull(msdu, sizeof(*rxd));
			skb_put(msdu, __le16_to_cpu(msdu_desc->msdu_len));

			if (!(__le32_to_cpu(rxd->attention.flags) &
			      RX_ATTENTION_FLAGS_MSDU_DONE)) {
				ath10k_warn(htt->ar, "tried to pop an incomplete frame, oops!\n");
				return -EIO;
			}
		}

		msdu_desc++;
	}

	return 0;
}

int ath10k_htt_rx_alloc(struct ath10k_htt *htt)
{
	struct ath10k *ar = htt->ar;
	dma_addr_t paddr;
	void *vaddr;
	size_t size;
	struct timer_list *timer = &htt->rx_ring.refill_retry_timer;

	htt->rx_confused = false;

	/* XXX: The fill level could be changed during runtime in response to
	 * the host processing latency. Is this really worth it?
	 */
	htt->rx_ring.size = HTT_RX_RING_SIZE;
	htt->rx_ring.size_mask = htt->rx_ring.size - 1;
	htt->rx_ring.fill_level = HTT_RX_RING_FILL_LEVEL;

	if (!is_power_of_2(htt->rx_ring.size)) {
		ath10k_warn(ar, "htt rx ring size is not power of 2\n");
		return -EINVAL;
	}

	htt->rx_ring.netbufs_ring =
		kzalloc(htt->rx_ring.size * sizeof(struct sk_buff *),
			GFP_KERNEL);
	if (!htt->rx_ring.netbufs_ring)
		goto err_netbuf;

	size = htt->rx_ring.size * sizeof(htt->rx_ring.paddrs_ring);

	vaddr = dma_alloc_coherent(htt->ar->dev, size, &paddr, GFP_DMA);
	if (!vaddr)
		goto err_dma_ring;

	htt->rx_ring.paddrs_ring = vaddr;
	htt->rx_ring.base_paddr = paddr;

	vaddr = dma_alloc_coherent(htt->ar->dev,
				   sizeof(*htt->rx_ring.alloc_idx.vaddr),
				   &paddr, GFP_DMA);
	if (!vaddr)
		goto err_dma_idx;

	htt->rx_ring.alloc_idx.vaddr = vaddr;
	htt->rx_ring.alloc_idx.paddr = paddr;
	htt->rx_ring.sw_rd_idx.msdu_payld = htt->rx_ring.size_mask;
	*htt->rx_ring.alloc_idx.vaddr = 0;

	/* Initialize the Rx refill retry timer */
	setup_timer(timer, ath10k_htt_rx_ring_refill_retry, (unsigned long)htt);

	spin_lock_init(&htt->rx_ring.lock);

	htt->rx_ring.fill_cnt = 0;
	htt->rx_ring.sw_rd_idx.msdu_payld = 0;
	hash_init(htt->rx_ring.skb_table);

	tasklet_init(&htt->rx_replenish_task, ath10k_htt_rx_replenish_task,
		     (unsigned long)htt);

	skb_queue_head_init(&htt->tx_compl_q);
	skb_queue_head_init(&htt->rx_compl_q);
	skb_queue_head_init(&htt->rx_in_ord_compl_q);

	tasklet_init(&htt->txrx_compl_task, ath10k_htt_txrx_compl_task,
		     (unsigned long)htt);

	ath10k_dbg(ar, ATH10K_DBG_BOOT, "htt rx ring size %d fill_level %d\n",
		   htt->rx_ring.size, htt->rx_ring.fill_level);
	return 0;

err_dma_idx:
	dma_free_coherent(htt->ar->dev,
			  (htt->rx_ring.size *
			   sizeof(htt->rx_ring.paddrs_ring)),
			  htt->rx_ring.paddrs_ring,
			  htt->rx_ring.base_paddr);
err_dma_ring:
	kfree(htt->rx_ring.netbufs_ring);
err_netbuf:
	return -ENOMEM;
}

static int ath10k_htt_rx_crypto_param_len(struct ath10k *ar,
					  enum htt_rx_mpdu_encrypt_type type)
{
	switch (type) {
	case HTT_RX_MPDU_ENCRYPT_NONE:
		return 0;
	case HTT_RX_MPDU_ENCRYPT_WEP40:
	case HTT_RX_MPDU_ENCRYPT_WEP104:
		return IEEE80211_WEP_IV_LEN;
	case HTT_RX_MPDU_ENCRYPT_TKIP_WITHOUT_MIC:
	case HTT_RX_MPDU_ENCRYPT_TKIP_WPA:
		return IEEE80211_TKIP_IV_LEN;
	case HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2:
		return IEEE80211_CCMP_HDR_LEN;
	case HTT_RX_MPDU_ENCRYPT_WEP128:
	case HTT_RX_MPDU_ENCRYPT_WAPI:
		break;
	}

	ath10k_warn(ar, "unsupported encryption type %d\n", type);
	return 0;
}

#define MICHAEL_MIC_LEN 8

static int ath10k_htt_rx_crypto_tail_len(struct ath10k *ar,
					 enum htt_rx_mpdu_encrypt_type type)
{
	switch (type) {
	case HTT_RX_MPDU_ENCRYPT_NONE:
		return 0;
	case HTT_RX_MPDU_ENCRYPT_WEP40:
	case HTT_RX_MPDU_ENCRYPT_WEP104:
		return IEEE80211_WEP_ICV_LEN;
	case HTT_RX_MPDU_ENCRYPT_TKIP_WITHOUT_MIC:
	case HTT_RX_MPDU_ENCRYPT_TKIP_WPA:
		return IEEE80211_TKIP_ICV_LEN;
	case HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2:
		return IEEE80211_CCMP_MIC_LEN;
	case HTT_RX_MPDU_ENCRYPT_WEP128:
	case HTT_RX_MPDU_ENCRYPT_WAPI:
		break;
	}

	ath10k_warn(ar, "unsupported encryption type %d\n", type);
	return 0;
}

struct amsdu_subframe_hdr {
	u8 dst[ETH_ALEN];
	u8 src[ETH_ALEN];
	__be16 len;
} __packed;

static void ath10k_htt_rx_h_rates(struct ath10k *ar,
				  struct ieee80211_rx_status *status,
				  struct htt_rx_desc *rxd)
{
	struct ieee80211_supported_band *sband;
	u8 cck, rate, bw, sgi, mcs, nss;
	u8 preamble = 0;
	u32 info1, info2, info3;

	info1 = __le32_to_cpu(rxd->ppdu_start.info1);
	info2 = __le32_to_cpu(rxd->ppdu_start.info2);
	info3 = __le32_to_cpu(rxd->ppdu_start.info3);

	preamble = MS(info1, RX_PPDU_START_INFO1_PREAMBLE_TYPE);

	switch (preamble) {
	case HTT_RX_LEGACY:
		/* To get legacy rate index band is required. Since band can't
		 * be undefined check if freq is non-zero.
		 */
		if (!status->freq)
			return;

		cck = info1 & RX_PPDU_START_INFO1_L_SIG_RATE_SELECT;
		rate = MS(info1, RX_PPDU_START_INFO1_L_SIG_RATE);
		rate &= ~RX_PPDU_START_RATE_FLAG;

		sband = &ar->mac.sbands[status->band];
		status->rate_idx = ath10k_mac_hw_rate_to_idx(sband, rate);
		break;
	case HTT_RX_HT:
	case HTT_RX_HT_WITH_TXBF:
		/* HT-SIG - Table 20-11 in info2 and info3 */
		mcs = info2 & 0x1F;
		nss = mcs >> 3;
		bw = (info2 >> 7) & 1;
		sgi = (info3 >> 7) & 1;

		status->rate_idx = mcs;
		status->flag |= RX_FLAG_HT;
		if (sgi)
			status->flag |= RX_FLAG_SHORT_GI;
		if (bw)
			status->flag |= RX_FLAG_40MHZ;
		break;
	case HTT_RX_VHT:
	case HTT_RX_VHT_WITH_TXBF:
		/* VHT-SIG-A1 in info2, VHT-SIG-A2 in info3
		   TODO check this */
		mcs = (info3 >> 4) & 0x0F;
		nss = ((info2 >> 10) & 0x07) + 1;
		bw = info2 & 3;
		sgi = info3 & 1;

		status->rate_idx = mcs;
		status->vht_nss = nss;

		if (sgi)
			status->flag |= RX_FLAG_SHORT_GI;

		switch (bw) {
		/* 20MHZ */
		case 0:
			break;
		/* 40MHZ */
		case 1:
			status->flag |= RX_FLAG_40MHZ;
			break;
		/* 80MHZ */
		case 2:
			status->vht_flag |= RX_VHT_FLAG_80MHZ;
		}

		status->flag |= RX_FLAG_VHT;
		break;
	default:
		break;
	}
}

static struct ieee80211_channel *
ath10k_htt_rx_h_peer_channel(struct ath10k *ar, struct htt_rx_desc *rxd)
{
	struct ath10k_peer *peer;
	struct ath10k_vif *arvif;
	struct cfg80211_chan_def def;
	u16 peer_id;

	lockdep_assert_held(&ar->data_lock);

	if (!rxd)
		return NULL;

	if (rxd->attention.flags &
	    __cpu_to_le32(RX_ATTENTION_FLAGS_PEER_IDX_INVALID))
		return NULL;

	if (!(rxd->msdu_end.common.info0 &
	      __cpu_to_le32(RX_MSDU_END_INFO0_FIRST_MSDU)))
		return NULL;

	peer_id = MS(__le32_to_cpu(rxd->mpdu_start.info0),
		     RX_MPDU_START_INFO0_PEER_IDX);

	peer = ath10k_peer_find_by_id(ar, peer_id);
	if (!peer)
		return NULL;

	arvif = ath10k_get_arvif(ar, peer->vdev_id);
	if (WARN_ON_ONCE(!arvif))
		return NULL;

	if (WARN_ON(ath10k_mac_vif_chan(arvif->vif, &def)))
		return NULL;

	return def.chan;
}

static struct ieee80211_channel *
ath10k_htt_rx_h_vdev_channel(struct ath10k *ar, u32 vdev_id)
{
	struct ath10k_vif *arvif;
	struct cfg80211_chan_def def;

	lockdep_assert_held(&ar->data_lock);

	list_for_each_entry(arvif, &ar->arvifs, list) {
		if (arvif->vdev_id == vdev_id &&
		    ath10k_mac_vif_chan(arvif->vif, &def) == 0)
			return def.chan;
	}

	return NULL;
}

static void
ath10k_htt_rx_h_any_chan_iter(struct ieee80211_hw *hw,
			      struct ieee80211_chanctx_conf *conf,
			      void *data)
{
	struct cfg80211_chan_def *def = data;

	*def = conf->def;
}

static struct ieee80211_channel *
ath10k_htt_rx_h_any_channel(struct ath10k *ar)
{
	struct cfg80211_chan_def def = {};

	ieee80211_iter_chan_contexts_atomic(ar->hw,
					    ath10k_htt_rx_h_any_chan_iter,
					    &def);

	return def.chan;
}

static bool ath10k_htt_rx_h_channel(struct ath10k *ar,
				    struct ieee80211_rx_status *status,
				    struct htt_rx_desc *rxd,
				    u32 vdev_id)
{
	struct ieee80211_channel *ch;

	spin_lock_bh(&ar->data_lock);
	ch = ar->scan_channel;
	if (!ch)
		ch = ar->rx_channel;
	if (!ch)
		ch = ath10k_htt_rx_h_peer_channel(ar, rxd);
	if (!ch)
		ch = ath10k_htt_rx_h_vdev_channel(ar, vdev_id);
	if (!ch)
		ch = ath10k_htt_rx_h_any_channel(ar);
	spin_unlock_bh(&ar->data_lock);

	if (!ch)
		return false;

	status->band = ch->band;
	status->freq = ch->center_freq;

	return true;
}

static void ath10k_htt_rx_h_signal(struct ath10k *ar,
				   struct ieee80211_rx_status *status,
				   struct htt_rx_desc *rxd)
{
	/* FIXME: Get real NF */
	status->signal = ATH10K_DEFAULT_NOISE_FLOOR +
			 rxd->ppdu_start.rssi_comb;
	status->flag &= ~RX_FLAG_NO_SIGNAL_VAL;
}

static void ath10k_htt_rx_h_mactime(struct ath10k *ar,
				    struct ieee80211_rx_status *status,
				    struct htt_rx_desc *rxd)
{
	/* FIXME: TSF is known only at the end of PPDU, in the last MPDU. This
	 * means all prior MSDUs in a PPDU are reported to mac80211 without the
	 * TSF. Is it worth holding frames until end of PPDU is known?
	 *
	 * FIXME: Can we get/compute 64bit TSF?
	 */
	status->mactime = __le32_to_cpu(rxd->ppdu_end.common.tsf_timestamp);
	status->flag |= RX_FLAG_MACTIME_END;
}

static void ath10k_htt_rx_h_ppdu(struct ath10k *ar,
				 struct sk_buff_head *amsdu,
				 struct ieee80211_rx_status *status,
				 u32 vdev_id)
{
	struct sk_buff *first;
	struct htt_rx_desc *rxd;
	bool is_first_ppdu;
	bool is_last_ppdu;

	if (skb_queue_empty(amsdu))
		return;

	first = skb_peek(amsdu);
	rxd = (void *)first->data - sizeof(*rxd);

	is_first_ppdu = !!(rxd->attention.flags &
			   __cpu_to_le32(RX_ATTENTION_FLAGS_FIRST_MPDU));
	is_last_ppdu = !!(rxd->attention.flags &
			  __cpu_to_le32(RX_ATTENTION_FLAGS_LAST_MPDU));

	if (is_first_ppdu) {
		/* New PPDU starts so clear out the old per-PPDU status. */
		status->freq = 0;
		status->rate_idx = 0;
		status->vht_nss = 0;
		status->vht_flag &= ~RX_VHT_FLAG_80MHZ;
		status->flag &= ~(RX_FLAG_HT |
				  RX_FLAG_VHT |
				  RX_FLAG_SHORT_GI |
				  RX_FLAG_40MHZ |
				  RX_FLAG_MACTIME_END);
		status->flag |= RX_FLAG_NO_SIGNAL_VAL;

		ath10k_htt_rx_h_signal(ar, status, rxd);
		ath10k_htt_rx_h_channel(ar, status, rxd, vdev_id);
		ath10k_htt_rx_h_rates(ar, status, rxd);
	}

	if (is_last_ppdu)
		ath10k_htt_rx_h_mactime(ar, status, rxd);
}

static const char * const tid_to_ac[] = {
	"BE",
	"BK",
	"BK",
	"BE",
	"VI",
	"VI",
	"VO",
	"VO",
};

static char *ath10k_get_tid(struct ieee80211_hdr *hdr, char *out, size_t size)
{
	u8 *qc;
	int tid;

	if (!ieee80211_is_data_qos(hdr->frame_control))
		return "";

	qc = ieee80211_get_qos_ctl(hdr);
	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
	if (tid < 8)
		snprintf(out, size, "tid %d (%s)", tid, tid_to_ac[tid]);
	else
		snprintf(out, size, "tid %d", tid);

	return out;
}

static void ath10k_process_rx(struct ath10k *ar,
			      struct ieee80211_rx_status *rx_status,
			      struct sk_buff *skb)
{
	struct ieee80211_rx_status *status;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	char tid[32];

	status = IEEE80211_SKB_RXCB(skb);
	*status = *rx_status;

	ath10k_dbg(ar, ATH10K_DBG_DATA,
		   "rx skb %p len %u peer %pM %s %s sn %u %s%s%s%s%s %srate_idx %u vht_nss %u freq %u band %u flag 0x%x fcs-err %i mic-err %i amsdu-more %i\n",
		   skb,
		   skb->len,
		   ieee80211_get_SA(hdr),
		   ath10k_get_tid(hdr, tid, sizeof(tid)),
		   is_multicast_ether_addr(ieee80211_get_DA(hdr)) ?
							"mcast" : "ucast",
		   (__le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4,
		   status->flag == 0 ? "legacy" : "",
		   status->flag & RX_FLAG_HT ? "ht" : "",
		   status->flag & RX_FLAG_VHT ? "vht" : "",
		   status->flag & RX_FLAG_40MHZ ? "40" : "",
		   status->vht_flag & RX_VHT_FLAG_80MHZ ? "80" : "",
		   status->flag & RX_FLAG_SHORT_GI ? "sgi " : "",
		   status->rate_idx,
		   status->vht_nss,
		   status->freq,
		   status->band, status->flag,
		   !!(status->flag & RX_FLAG_FAILED_FCS_CRC),
		   !!(status->flag & RX_FLAG_MMIC_ERROR),
		   !!(status->flag & RX_FLAG_AMSDU_MORE));
	ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "rx skb: ",
			skb->data, skb->len);
	trace_ath10k_rx_hdr(ar, skb->data, skb->len);
	trace_ath10k_rx_payload(ar, skb->data, skb->len);

	ieee80211_rx(ar->hw, skb);
}

static int ath10k_htt_rx_nwifi_hdrlen(struct ath10k *ar,
				      struct ieee80211_hdr *hdr)
{
	int len = ieee80211_hdrlen(hdr->frame_control);

	if (!test_bit(ATH10K_FW_FEATURE_NO_NWIFI_DECAP_4ADDR_PADDING,
		      ar->fw_features))
		len = round_up(len, 4);

	return len;
}

static void ath10k_htt_rx_h_undecap_raw(struct ath10k *ar,
					struct sk_buff *msdu,
					struct ieee80211_rx_status *status,
					enum htt_rx_mpdu_encrypt_type enctype,
					bool is_decrypted)
{
	struct ieee80211_hdr *hdr;
	struct htt_rx_desc *rxd;
	size_t hdr_len;
	size_t crypto_len;
	bool is_first;
	bool is_last;

	rxd = (void *)msdu->data - sizeof(*rxd);
	is_first = !!(rxd->msdu_end.common.info0 &
		      __cpu_to_le32(RX_MSDU_END_INFO0_FIRST_MSDU));
	is_last = !!(rxd->msdu_end.common.info0 &
		     __cpu_to_le32(RX_MSDU_END_INFO0_LAST_MSDU));

	/* Delivered decapped frame:
	 * [802.11 header]
	 * [crypto param] <-- can be trimmed if !fcs_err &&
	 *                    !decrypt_err && !peer_idx_invalid
	 * [amsdu header] <-- only if A-MSDU
	 * [rfc1042/llc]
	 * [payload]
	 * [FCS] <-- at end, needs to be trimmed
	 */

	/* This probably shouldn't happen but warn just in case */
	if (unlikely(WARN_ON_ONCE(!is_first)))
		return;

	/* This probably shouldn't happen but warn just in case */
	if (unlikely(WARN_ON_ONCE(!(is_first && is_last))))
		return;

	skb_trim(msdu, msdu->len - FCS_LEN);

	/* In most cases this will be true for sniffed frames. It makes sense
	 * to deliver them as-is without stripping the crypto param. This is
	 * necessary for software based decryption.
	 *
	 * If there's no error then the frame is decrypted. At least that is
	 * the case for frames that come in via fragmented rx indication.
	 */
	if (!is_decrypted)
		return;

	/* The payload is decrypted so strip crypto params. Start from tail
	 * since hdr is used to compute some stuff.
	 */

	hdr = (void *)msdu->data;

	/* Tail */
	skb_trim(msdu, msdu->len - ath10k_htt_rx_crypto_tail_len(ar, enctype));

	/* MMIC */
	if (!ieee80211_has_morefrags(hdr->frame_control) &&
	    enctype == HTT_RX_MPDU_ENCRYPT_TKIP_WPA)
		skb_trim(msdu, msdu->len - 8);

	/* Head */
	hdr_len = ieee80211_hdrlen(hdr->frame_control);
	crypto_len = ath10k_htt_rx_crypto_param_len(ar, enctype);

	memmove((void *)msdu->data + crypto_len,
		(void *)msdu->data, hdr_len);
	skb_pull(msdu, crypto_len);
}

static void ath10k_htt_rx_h_undecap_nwifi(struct ath10k *ar,
					  struct sk_buff *msdu,
					  struct ieee80211_rx_status *status,
					  const u8 first_hdr[64])
{
	struct ieee80211_hdr *hdr;
	size_t hdr_len;
	u8 da[ETH_ALEN];
	u8 sa[ETH_ALEN];

	/* Delivered decapped frame:
	 * [nwifi 802.11 header] <-- replaced with 802.11 hdr
	 * [rfc1042/llc]
	 *
	 * Note: The nwifi header doesn't have QoS Control and is
	 * (always?) a 3addr frame.
	 *
	 * Note2: There's no A-MSDU subframe header. Even if it's part
	 * of an A-MSDU.
	 */

	/* pull decapped header and copy SA & DA */
	hdr = (struct ieee80211_hdr *)msdu->data;
	hdr_len = ath10k_htt_rx_nwifi_hdrlen(ar, hdr);
	ether_addr_copy(da, ieee80211_get_DA(hdr));
	ether_addr_copy(sa, ieee80211_get_SA(hdr));
	skb_pull(msdu, hdr_len);

	/* push original 802.11 header */
	hdr = (struct ieee80211_hdr *)first_hdr;
	hdr_len = ieee80211_hdrlen(hdr->frame_control);
	memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);

	/* original 802.11 header has a different DA and in
	 * case of 4addr it may also have different SA
	 */
	hdr = (struct ieee80211_hdr *)msdu->data;
	ether_addr_copy(ieee80211_get_DA(hdr), da);
	ether_addr_copy(ieee80211_get_SA(hdr), sa);
}

static void *ath10k_htt_rx_h_find_rfc1042(struct ath10k *ar,
					  struct sk_buff *msdu,
					  enum htt_rx_mpdu_encrypt_type enctype)
{
	struct ieee80211_hdr *hdr;
	struct htt_rx_desc *rxd;
	size_t hdr_len, crypto_len;
	void *rfc1042;
	bool is_first, is_last, is_amsdu;

	rxd = (void *)msdu->data - sizeof(*rxd);
	hdr = (void *)rxd->rx_hdr_status;

	is_first = !!(rxd->msdu_end.common.info0 &
		      __cpu_to_le32(RX_MSDU_END_INFO0_FIRST_MSDU));
	is_last = !!(rxd->msdu_end.common.info0 &
		     __cpu_to_le32(RX_MSDU_END_INFO0_LAST_MSDU));
	is_amsdu = !(is_first && is_last);

	rfc1042 = hdr;

	if (is_first) {
		hdr_len = ieee80211_hdrlen(hdr->frame_control);
		crypto_len = ath10k_htt_rx_crypto_param_len(ar, enctype);

		rfc1042 += round_up(hdr_len, 4) +
			   round_up(crypto_len, 4);
	}

	if (is_amsdu)
		rfc1042 += sizeof(struct amsdu_subframe_hdr);

	return rfc1042;
}

static void ath10k_htt_rx_h_undecap_eth(struct ath10k *ar,
					struct sk_buff *msdu,
					struct ieee80211_rx_status *status,
					const u8 first_hdr[64],
					enum htt_rx_mpdu_encrypt_type enctype)
{
	struct ieee80211_hdr *hdr;
	struct ethhdr *eth;
	size_t hdr_len;
	void *rfc1042;
	u8 da[ETH_ALEN];
	u8 sa[ETH_ALEN];

	/* Delivered decapped frame:
	 * [eth header] <-- replaced with 802.11 hdr & rfc1042/llc
	 * [payload]
	 */

	rfc1042 = ath10k_htt_rx_h_find_rfc1042(ar, msdu, enctype);
	if (WARN_ON_ONCE(!rfc1042))
		return;

	/* pull decapped header and copy SA & DA */
	eth = (struct ethhdr *)msdu->data;
	ether_addr_copy(da, eth->h_dest);
	ether_addr_copy(sa, eth->h_source);
	skb_pull(msdu, sizeof(struct ethhdr));

	/* push rfc1042/llc/snap */
	memcpy(skb_push(msdu, sizeof(struct rfc1042_hdr)), rfc1042,
	       sizeof(struct rfc1042_hdr));

	/* push original 802.11 header */
	hdr = (struct ieee80211_hdr *)first_hdr;
	hdr_len = ieee80211_hdrlen(hdr->frame_control);
	memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);

	/* original 802.11 header has a different DA and in
	 * case of 4addr it may also have different SA
	 */
	hdr = (struct ieee80211_hdr *)msdu->data;
	ether_addr_copy(ieee80211_get_DA(hdr), da);
	ether_addr_copy(ieee80211_get_SA(hdr), sa);
}

static void ath10k_htt_rx_h_undecap_snap(struct ath10k *ar,
					 struct sk_buff *msdu,
					 struct ieee80211_rx_status *status,
					 const u8 first_hdr[64])
{
	struct ieee80211_hdr *hdr;
	size_t hdr_len;

	/* Delivered decapped frame:
	 * [amsdu header] <-- replaced with 802.11 hdr
	 * [rfc1042/llc]
	 * [payload]
	 */

	skb_pull(msdu, sizeof(struct amsdu_subframe_hdr));

	hdr = (struct ieee80211_hdr *)first_hdr;
	hdr_len = ieee80211_hdrlen(hdr->frame_control);
	memcpy(skb_push(msdu, hdr_len), hdr, hdr_len);
}

static void ath10k_htt_rx_h_undecap(struct ath10k *ar,
				    struct sk_buff *msdu,
				    struct ieee80211_rx_status *status,
				    u8 first_hdr[64],
				    enum htt_rx_mpdu_encrypt_type enctype,
				    bool is_decrypted)
{
	struct htt_rx_desc *rxd;
	enum rx_msdu_decap_format decap;

	/* First msdu's decapped header:
	 * [802.11 header] <-- padded to 4 bytes long
	 * [crypto param] <-- padded to 4 bytes long
	 * [amsdu header] <-- only if A-MSDU
	 * [rfc1042/llc]
	 *
	 * Other (2nd, 3rd, ..) msdu's decapped header:
	 * [amsdu header] <-- only if A-MSDU
	 * [rfc1042/llc]
	 */

	rxd = (void *)msdu->data - sizeof(*rxd);
	decap = MS(__le32_to_cpu(rxd->msdu_start.common.info1),
		   RX_MSDU_START_INFO1_DECAP_FORMAT);

	switch (decap) {
	case RX_MSDU_DECAP_RAW:
		ath10k_htt_rx_h_undecap_raw(ar, msdu, status, enctype,
					    is_decrypted);
		break;
	case RX_MSDU_DECAP_NATIVE_WIFI:
		ath10k_htt_rx_h_undecap_nwifi(ar, msdu, status, first_hdr);
		break;
	case RX_MSDU_DECAP_ETHERNET2_DIX:
		ath10k_htt_rx_h_undecap_eth(ar, msdu, status, first_hdr, enctype);
		break;
	case RX_MSDU_DECAP_8023_SNAP_LLC:
		ath10k_htt_rx_h_undecap_snap(ar, msdu, status, first_hdr);
		break;
	}
}

static int ath10k_htt_rx_get_csum_state(struct sk_buff *skb)
{
	struct htt_rx_desc *rxd;
	u32 flags, info;
	bool is_ip4, is_ip6;
	bool is_tcp, is_udp;
	bool ip_csum_ok, tcpudp_csum_ok;

	rxd = (void *)skb->data - sizeof(*rxd);
	flags = __le32_to_cpu(rxd->attention.flags);
	info = __le32_to_cpu(rxd->msdu_start.common.info1);

	is_ip4 = !!(info & RX_MSDU_START_INFO1_IPV4_PROTO);
	is_ip6 = !!(info & RX_MSDU_START_INFO1_IPV6_PROTO);
	is_tcp = !!(info & RX_MSDU_START_INFO1_TCP_PROTO);
	is_udp = !!(info & RX_MSDU_START_INFO1_UDP_PROTO);
	ip_csum_ok = !(flags & RX_ATTENTION_FLAGS_IP_CHKSUM_FAIL);
	tcpudp_csum_ok = !(flags & RX_ATTENTION_FLAGS_TCP_UDP_CHKSUM_FAIL);

	if (!is_ip4 && !is_ip6)
		return CHECKSUM_NONE;
	if (!is_tcp && !is_udp)
		return CHECKSUM_NONE;
	if (!ip_csum_ok)
		return CHECKSUM_NONE;
	if (!tcpudp_csum_ok)
		return CHECKSUM_NONE;

	return CHECKSUM_UNNECESSARY;
}

static void ath10k_htt_rx_h_csum_offload(struct sk_buff *msdu)
{
	msdu->ip_summed = ath10k_htt_rx_get_csum_state(msdu);
}

static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
				 struct sk_buff_head *amsdu,
				 struct ieee80211_rx_status *status)
{
	struct sk_buff *first;
	struct sk_buff *last;
	struct sk_buff *msdu;
	struct htt_rx_desc *rxd;
	struct ieee80211_hdr *hdr;
	enum htt_rx_mpdu_encrypt_type enctype;
	u8 first_hdr[64];
	u8 *qos;
	size_t hdr_len;
	bool has_fcs_err;
	bool has_crypto_err;
	bool has_tkip_err;
	bool has_peer_idx_invalid;
	bool is_decrypted;
	u32 attention;

	if (skb_queue_empty(amsdu))
		return;

	first = skb_peek(amsdu);
	rxd = (void *)first->data - sizeof(*rxd);

	enctype = MS(__le32_to_cpu(rxd->mpdu_start.info0),
		     RX_MPDU_START_INFO0_ENCRYPT_TYPE);

	/* First MSDU's Rx descriptor in an A-MSDU contains full 802.11
	 * decapped header. It'll be used for undecapping of each MSDU.
	 */
	hdr = (void *)rxd->rx_hdr_status;
	hdr_len = ieee80211_hdrlen(hdr->frame_control);
	memcpy(first_hdr, hdr, hdr_len);

	/* Each A-MSDU subframe will use the original header as the base and be
	 * reported as a separate MSDU so strip the A-MSDU bit from QoS Ctl.
	 */
	hdr = (void *)first_hdr;
	qos = ieee80211_get_qos_ctl(hdr);
	qos[0] &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT;

	/* Some attention flags are valid only in the last MSDU. */
	last = skb_peek_tail(amsdu);
	rxd = (void *)last->data - sizeof(*rxd);
	attention = __le32_to_cpu(rxd->attention.flags);

	has_fcs_err = !!(attention & RX_ATTENTION_FLAGS_FCS_ERR);
	has_crypto_err = !!(attention & RX_ATTENTION_FLAGS_DECRYPT_ERR);
	has_tkip_err = !!(attention & RX_ATTENTION_FLAGS_TKIP_MIC_ERR);
	has_peer_idx_invalid = !!(attention & RX_ATTENTION_FLAGS_PEER_IDX_INVALID);

	/* Note: If hardware captures an encrypted frame that it can't decrypt,
	 * e.g. due to fcs error, missing peer or invalid key data it will
	 * report the frame as raw.
	 */
	is_decrypted = (enctype != HTT_RX_MPDU_ENCRYPT_NONE &&
			!has_fcs_err &&
			!has_crypto_err &&
			!has_peer_idx_invalid);

	/* Clear per-MPDU flags while leaving per-PPDU flags intact. */
	status->flag &= ~(RX_FLAG_FAILED_FCS_CRC |
			  RX_FLAG_MMIC_ERROR |
			  RX_FLAG_DECRYPTED |
			  RX_FLAG_IV_STRIPPED |
			  RX_FLAG_MMIC_STRIPPED);

	if (has_fcs_err)
		status->flag |= RX_FLAG_FAILED_FCS_CRC;

	if (has_tkip_err)
		status->flag |= RX_FLAG_MMIC_ERROR;

	if (is_decrypted)
		status->flag |= RX_FLAG_DECRYPTED |
				RX_FLAG_IV_STRIPPED |
				RX_FLAG_MMIC_STRIPPED;

	skb_queue_walk(amsdu, msdu) {
		ath10k_htt_rx_h_csum_offload(msdu);
		ath10k_htt_rx_h_undecap(ar, msdu, status, first_hdr, enctype,
					is_decrypted);

		/* Undecapping involves copying the original 802.11 header back
		 * to sk_buff. If frame is protected and hardware has decrypted
		 * it then remove the protected bit.
		 */
		if (!is_decrypted)
			continue;

		hdr = (void *)msdu->data;
		hdr->frame_control &= ~__cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	}
}

static void ath10k_htt_rx_h_deliver(struct ath10k *ar,
				    struct sk_buff_head *amsdu,
				    struct ieee80211_rx_status *status)
{
	struct sk_buff *msdu;

	while ((msdu = __skb_dequeue(amsdu))) {
		/* Setup per-MSDU flags */
		if (skb_queue_empty(amsdu))
			status->flag &= ~RX_FLAG_AMSDU_MORE;
		else
			status->flag |= RX_FLAG_AMSDU_MORE;

		ath10k_process_rx(ar, status, msdu);
	}
}

static int ath10k_unchain_msdu(struct sk_buff_head *amsdu)
{
	struct sk_buff *skb, *first;
	int space;
	int total_len = 0;

	/* TODO:  Might could optimize this by using
	 * skb_try_coalesce or similar method to
	 * decrease copying, or maybe get mac80211 to
	 * provide a way to just receive a list of
	 * skb?
	 */

	first = __skb_dequeue(amsdu);

	/* Allocate total length all at once. */
	skb_queue_walk(amsdu, skb)
		total_len += skb->len;

	space = total_len - skb_tailroom(first);
	if ((space > 0) &&
	    (pskb_expand_head(first, 0, space, GFP_ATOMIC) < 0)) {
		/* TODO:  bump some rx-oom error stat */
		/* put it back together so we can free the
		 * whole list at once.
		 */
		__skb_queue_head(amsdu, first);
		return -1;
	}

	/* Walk list again, copying contents into
	 * msdu_head
	 */
	while ((skb = __skb_dequeue(amsdu))) {
		skb_copy_from_linear_data(skb, skb_put(first, skb->len),
					  skb->len);
		dev_kfree_skb_any(skb);
	}

	__skb_queue_head(amsdu, first);
	return 0;
}

static void ath10k_htt_rx_h_unchain(struct ath10k *ar,
				    struct sk_buff_head *amsdu,
				    bool chained)
{
	struct sk_buff *first;
	struct htt_rx_desc *rxd;
	enum rx_msdu_decap_format decap;

	first = skb_peek(amsdu);
	rxd = (void *)first->data - sizeof(*rxd);
	decap = MS(__le32_to_cpu(rxd->msdu_start.common.info1),
		   RX_MSDU_START_INFO1_DECAP_FORMAT);

	if (!chained)
		return;

	/* FIXME: Current unchaining logic can only handle simple case of raw
	 * msdu chaining. If decapping is other than raw the chaining may be
	 * more complex and this isn't handled by the current code. Don't even
	 * try re-constructing such frames - it'll be pretty much garbage.
	 */
	if (decap != RX_MSDU_DECAP_RAW ||
	    skb_queue_len(amsdu) != 1 + rxd->frag_info.ring2_more_count) {
		__skb_queue_purge(amsdu);
		return;
	}

	ath10k_unchain_msdu(amsdu);
}

static bool ath10k_htt_rx_amsdu_allowed(struct ath10k *ar,
					struct sk_buff_head *amsdu,
					struct ieee80211_rx_status *rx_status)
{
	struct sk_buff *msdu;
	struct htt_rx_desc *rxd;
	bool is_mgmt;
	bool has_fcs_err;

	msdu = skb_peek(amsdu);
	rxd = (void *)msdu->data - sizeof(*rxd);

	/* FIXME: It might be a good idea to do some fuzzy-testing to drop
	 * invalid/dangerous frames.
	 */

	if (!rx_status->freq) {
		ath10k_warn(ar, "no channel configured; ignoring frame(s)!\n");
		return false;
	}

	is_mgmt = !!(rxd->attention.flags &
		     __cpu_to_le32(RX_ATTENTION_FLAGS_MGMT_TYPE));
	has_fcs_err = !!(rxd->attention.flags &
			 __cpu_to_le32(RX_ATTENTION_FLAGS_FCS_ERR));

	/* Management frames are handled via WMI events. The pros of such
	 * approach is that channel is explicitly provided in WMI events
	 * whereas HTT doesn't provide channel information for Rxed frames.
	 *
	 * However some firmware revisions don't report corrupted frames via
	 * WMI so don't drop them.
	 */
	if (is_mgmt && !has_fcs_err) {
		ath10k_dbg(ar, ATH10K_DBG_HTT, "htt rx mgmt ctrl\n");
		return false;
	}

	if (test_bit(ATH10K_CAC_RUNNING, &ar->dev_flags)) {
		ath10k_dbg(ar, ATH10K_DBG_HTT, "htt rx cac running\n");
		return false;
	}

	return true;
}

static void ath10k_htt_rx_h_filter(struct ath10k *ar,
				   struct sk_buff_head *amsdu,
				   struct ieee80211_rx_status *rx_status)
{
	if (skb_queue_empty(amsdu))
		return;

	if (ath10k_htt_rx_amsdu_allowed(ar, amsdu, rx_status))
		return;

	__skb_queue_purge(amsdu);
}

static void ath10k_htt_rx_handler(struct ath10k_htt *htt,
				  struct htt_rx_indication *rx)
{
	struct ath10k *ar = htt->ar;
	struct ieee80211_rx_status *rx_status = &htt->rx_status;
	struct htt_rx_indication_mpdu_range *mpdu_ranges;
	struct sk_buff_head amsdu;
	int num_mpdu_ranges;
	int fw_desc_len;
	u8 *fw_desc;
	int i, ret, mpdu_count = 0;

	lockdep_assert_held(&htt->rx_ring.lock);

	if (htt->rx_confused)
		return;

	fw_desc_len = __le16_to_cpu(rx->prefix.fw_rx_desc_bytes);
	fw_desc = (u8 *)&rx->fw_desc;

	num_mpdu_ranges = MS(__le32_to_cpu(rx->hdr.info1),
			     HTT_RX_INDICATION_INFO1_NUM_MPDU_RANGES);
	mpdu_ranges = htt_rx_ind_get_mpdu_ranges(rx);

	ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt rx ind: ",
			rx, sizeof(*rx) +
			(sizeof(struct htt_rx_indication_mpdu_range) *
				num_mpdu_ranges));

	for (i = 0; i < num_mpdu_ranges; i++)
		mpdu_count += mpdu_ranges[i].mpdu_count;

	while (mpdu_count--) {
		__skb_queue_head_init(&amsdu);
		ret = ath10k_htt_rx_amsdu_pop(htt, &fw_desc,
					      &fw_desc_len, &amsdu);
		if (ret < 0) {
			ath10k_warn(ar, "rx ring became corrupted: %d\n", ret);
			__skb_queue_purge(&amsdu);
			/* FIXME: It's probably a good idea to reboot the
			 * device instead of leaving it inoperable.
			 */
			htt->rx_confused = true;
			break;
		}

		ath10k_htt_rx_h_ppdu(ar, &amsdu, rx_status, 0xffff);
		ath10k_htt_rx_h_unchain(ar, &amsdu, ret > 0);
		ath10k_htt_rx_h_filter(ar, &amsdu, rx_status);
		ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status);
		ath10k_htt_rx_h_deliver(ar, &amsdu, rx_status);
	}

	tasklet_schedule(&htt->rx_replenish_task);
}

static void ath10k_htt_rx_frag_handler(struct ath10k_htt *htt,
				       struct htt_rx_fragment_indication *frag)
{
	struct ath10k *ar = htt->ar;
	struct ieee80211_rx_status *rx_status = &htt->rx_status;
	struct sk_buff_head amsdu;
	int ret;
	u8 *fw_desc;
	int fw_desc_len;

	fw_desc_len = __le16_to_cpu(frag->fw_rx_desc_bytes);
	fw_desc = (u8 *)frag->fw_msdu_rx_desc;

	__skb_queue_head_init(&amsdu);

	spin_lock_bh(&htt->rx_ring.lock);
	ret = ath10k_htt_rx_amsdu_pop(htt, &fw_desc, &fw_desc_len,
				      &amsdu);
	spin_unlock_bh(&htt->rx_ring.lock);

	tasklet_schedule(&htt->rx_replenish_task);

	ath10k_dbg(ar, ATH10K_DBG_HTT_DUMP, "htt rx frag ahead\n");

	if (ret) {
		ath10k_warn(ar, "failed to pop amsdu from httr rx ring for fragmented rx %d\n",
			    ret);
		__skb_queue_purge(&amsdu);
		return;
	}

	if (skb_queue_len(&amsdu) != 1) {
		ath10k_warn(ar, "failed to pop frag amsdu: too many msdus\n");
		__skb_queue_purge(&amsdu);
		return;
	}

	ath10k_htt_rx_h_ppdu(ar, &amsdu, rx_status, 0xffff);
	ath10k_htt_rx_h_filter(ar, &amsdu, rx_status);
	ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status);
	ath10k_htt_rx_h_deliver(ar, &amsdu, rx_status);

	if (fw_desc_len > 0) {
		ath10k_dbg(ar, ATH10K_DBG_HTT,
			   "expecting more fragmented rx in one indication %d\n",
			   fw_desc_len);
	}
}

static void ath10k_htt_rx_frm_tx_compl(struct ath10k *ar,
				       struct sk_buff *skb)
{
	struct ath10k_htt *htt = &ar->htt;
	struct htt_resp *resp = (struct htt_resp *)skb->data;
	struct htt_tx_done tx_done = {};
	int status = MS(resp->data_tx_completion.flags, HTT_DATA_TX_STATUS);
	__le16 msdu_id;
	int i;

	switch (status) {
	case HTT_DATA_TX_STATUS_NO_ACK:
		tx_done.no_ack = true;
		break;
	case HTT_DATA_TX_STATUS_OK:
		tx_done.success = true;
		break;
	case HTT_DATA_TX_STATUS_DISCARD:
	case HTT_DATA_TX_STATUS_POSTPONE:
	case HTT_DATA_TX_STATUS_DOWNLOAD_FAIL:
		tx_done.discard = true;
		break;
	default:
		ath10k_warn(ar, "unhandled tx completion status %d\n", status);
		tx_done.discard = true;
		break;
	}

	ath10k_dbg(ar, ATH10K_DBG_HTT, "htt tx completion num_msdus %d\n",
		   resp->data_tx_completion.num_msdus);

	for (i = 0; i < resp->data_tx_completion.num_msdus; i++) {
		msdu_id = resp->data_tx_completion.msdus[i];
		tx_done.msdu_id = __le16_to_cpu(msdu_id);
		ath10k_txrx_tx_unref(htt, &tx_done);
	}
}

static void ath10k_htt_rx_addba(struct ath10k *ar, struct htt_resp *resp)
{
	struct htt_rx_addba *ev = &resp->rx_addba;
	struct ath10k_peer *peer;
	struct ath10k_vif *arvif;
	u16 info0, tid, peer_id;

	info0 = __le16_to_cpu(ev->info0);
	tid = MS(info0, HTT_RX_BA_INFO0_TID);
	peer_id = MS(info0, HTT_RX_BA_INFO0_PEER_ID);

	ath10k_dbg(ar, ATH10K_DBG_HTT,
		   "htt rx addba tid %hu peer_id %hu size %hhu\n",
		   tid, peer_id, ev->window_size);

	spin_lock_bh(&ar->data_lock);
	peer = ath10k_peer_find_by_id(ar, peer_id);
	if (!peer) {
		ath10k_warn(ar, "received addba event for invalid peer_id: %hu\n",
			    peer_id);
		spin_unlock_bh(&ar->data_lock);
		return;
	}

	arvif = ath10k_get_arvif(ar, peer->vdev_id);
	if (!arvif) {
		ath10k_warn(ar, "received addba event for invalid vdev_id: %u\n",
			    peer->vdev_id);
		spin_unlock_bh(&ar->data_lock);
		return;
	}

	ath10k_dbg(ar, ATH10K_DBG_HTT,
		   "htt rx start rx ba session sta %pM tid %hu size %hhu\n",
		   peer->addr, tid, ev->window_size);

	ieee80211_start_rx_ba_session_offl(arvif->vif, peer->addr, tid);
	spin_unlock_bh(&ar->data_lock);
}

static void ath10k_htt_rx_delba(struct ath10k *ar, struct htt_resp *resp)
{
	struct htt_rx_delba *ev = &resp->rx_delba;
	struct ath10k_peer *peer;
	struct ath10k_vif *arvif;
	u16 info0, tid, peer_id;

	info0 = __le16_to_cpu(ev->info0);
	tid = MS(info0, HTT_RX_BA_INFO0_TID);
	peer_id = MS(info0, HTT_RX_BA_INFO0_PEER_ID);

	ath10k_dbg(ar, ATH10K_DBG_HTT,
		   "htt rx delba tid %hu peer_id %hu\n",
		   tid, peer_id);

	spin_lock_bh(&ar->data_lock);
	peer = ath10k_peer_find_by_id(ar, peer_id);
	if (!peer) {
		ath10k_warn(ar, "received addba event for invalid peer_id: %hu\n",
			    peer_id);
		spin_unlock_bh(&ar->data_lock);
		return;
	}

	arvif = ath10k_get_arvif(ar, peer->vdev_id);
	if (!arvif) {
		ath10k_warn(ar, "received addba event for invalid vdev_id: %u\n",
			    peer->vdev_id);
		spin_unlock_bh(&ar->data_lock);
		return;
	}

	ath10k_dbg(ar, ATH10K_DBG_HTT,
		   "htt rx stop rx ba session sta %pM tid %hu\n",
		   peer->addr, tid);

	ieee80211_stop_rx_ba_session_offl(arvif->vif, peer->addr, tid);
	spin_unlock_bh(&ar->data_lock);
}

static int ath10k_htt_rx_extract_amsdu(struct sk_buff_head *list,
				       struct sk_buff_head *amsdu)
{
	struct sk_buff *msdu;
	struct htt_rx_desc *rxd;

	if (skb_queue_empty(list))
		return -ENOBUFS;

	if (WARN_ON(!skb_queue_empty(amsdu)))
		return -EINVAL;

	while ((msdu = __skb_dequeue(list))) {
		__skb_queue_tail(amsdu, msdu);

		rxd = (void *)msdu->data - sizeof(*rxd);
		if (rxd->msdu_end.common.info0 &
		    __cpu_to_le32(RX_MSDU_END_INFO0_LAST_MSDU))
			break;
	}

	msdu = skb_peek_tail(amsdu);
	rxd = (void *)msdu->data - sizeof(*rxd);
	if (!(rxd->msdu_end.common.info0 &
	      __cpu_to_le32(RX_MSDU_END_INFO0_LAST_MSDU))) {
		skb_queue_splice_init(amsdu, list);
		return -EAGAIN;
	}

	return 0;
}

static void ath10k_htt_rx_h_rx_offload_prot(struct ieee80211_rx_status *status,
					    struct sk_buff *skb)
{
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;

	if (!ieee80211_has_protected(hdr->frame_control))
		return;

	/* Offloaded frames are already decrypted but firmware insists they are
	 * protected in the 802.11 header. Strip the flag.  Otherwise mac80211
	 * will drop the frame.
	 */

	hdr->frame_control &= ~__cpu_to_le16(IEEE80211_FCTL_PROTECTED);
	status->flag |= RX_FLAG_DECRYPTED |
			RX_FLAG_IV_STRIPPED |
			RX_FLAG_MMIC_STRIPPED;
}

static void ath10k_htt_rx_h_rx_offload(struct ath10k *ar,
				       struct sk_buff_head *list)
{
	struct ath10k_htt *htt = &ar->htt;
	struct ieee80211_rx_status *status = &htt->rx_status;
	struct htt_rx_offload_msdu *rx;
	struct sk_buff *msdu;
	size_t offset;

	while ((msdu = __skb_dequeue(list))) {
		/* Offloaded frames don't have Rx descriptor. Instead they have
		 * a short meta information header.
		 */

		rx = (void *)msdu->data;

		skb_put(msdu, sizeof(*rx));
		skb_pull(msdu, sizeof(*rx));

		if (skb_tailroom(msdu) < __le16_to_cpu(rx->msdu_len)) {
			ath10k_warn(ar, "dropping frame: offloaded rx msdu is too long!\n");
			dev_kfree_skb_any(msdu);
			continue;
		}

		skb_put(msdu, __le16_to_cpu(rx->msdu_len));

		/* Offloaded rx header length isn't multiple of 2 nor 4 so the
		 * actual payload is unaligned. Align the frame.  Otherwise
		 * mac80211 complains.  This shouldn't reduce performance much
		 * because these offloaded frames are rare.
		 */
		offset = 4 - ((unsigned long)msdu->data & 3);
		skb_put(msdu, offset);
		memmove(msdu->data + offset, msdu->data, msdu->len);
		skb_pull(msdu, offset);

		/* FIXME: The frame is NWifi. Re-construct QoS Control
		 * if possible later.
		 */

		memset(status, 0, sizeof(*status));
		status->flag |= RX_FLAG_NO_SIGNAL_VAL;

		ath10k_htt_rx_h_rx_offload_prot(status, msdu);
		ath10k_htt_rx_h_channel(ar, status, NULL, rx->vdev_id);
		ath10k_process_rx(ar, status, msdu);
	}
}

static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
{
	struct ath10k_htt *htt = &ar->htt;
	struct htt_resp *resp = (void *)skb->data;
	struct ieee80211_rx_status *status = &htt->rx_status;
	struct sk_buff_head list;
	struct sk_buff_head amsdu;
	u16 peer_id;
	u16 msdu_count;
	u8 vdev_id;
	u8 tid;
	bool offload;
	bool frag;
	int ret;

	lockdep_assert_held(&htt->rx_ring.lock);

	if (htt->rx_confused)
		return;

	skb_pull(skb, sizeof(resp->hdr));
	skb_pull(skb, sizeof(resp->rx_in_ord_ind));

	peer_id = __le16_to_cpu(resp->rx_in_ord_ind.peer_id);
	msdu_count = __le16_to_cpu(resp->rx_in_ord_ind.msdu_count);
	vdev_id = resp->rx_in_ord_ind.vdev_id;
	tid = SM(resp->rx_in_ord_ind.info, HTT_RX_IN_ORD_IND_INFO_TID);
	offload = !!(resp->rx_in_ord_ind.info &
			HTT_RX_IN_ORD_IND_INFO_OFFLOAD_MASK);
	frag = !!(resp->rx_in_ord_ind.info & HTT_RX_IN_ORD_IND_INFO_FRAG_MASK);

	ath10k_dbg(ar, ATH10K_DBG_HTT,
		   "htt rx in ord vdev %i peer %i tid %i offload %i frag %i msdu count %i\n",
		   vdev_id, peer_id, tid, offload, frag, msdu_count);

	if (skb->len < msdu_count * sizeof(*resp->rx_in_ord_ind.msdu_descs)) {
		ath10k_warn(ar, "dropping invalid in order rx indication\n");
		return;
	}

	/* The event can deliver more than 1 A-MSDU. Each A-MSDU is later
	 * extracted and processed.
	 */
	__skb_queue_head_init(&list);
	ret = ath10k_htt_rx_pop_paddr_list(htt, &resp->rx_in_ord_ind, &list);
	if (ret < 0) {
		ath10k_warn(ar, "failed to pop paddr list: %d\n", ret);
		htt->rx_confused = true;
		return;
	}

	/* Offloaded frames are very different and need to be handled
	 * separately.
	 */
	if (offload)
		ath10k_htt_rx_h_rx_offload(ar, &list);

	while (!skb_queue_empty(&list)) {
		__skb_queue_head_init(&amsdu);
		ret = ath10k_htt_rx_extract_amsdu(&list, &amsdu);
		switch (ret) {
		case 0:
			/* Note: The in-order indication may report interleaved
			 * frames from different PPDUs meaning reported rx rate
			 * to mac80211 isn't accurate/reliable. It's still
			 * better to report something than nothing though. This
			 * should still give an idea about rx rate to the user.
			 */
			ath10k_htt_rx_h_ppdu(ar, &amsdu, status, vdev_id);
			ath10k_htt_rx_h_filter(ar, &amsdu, status);
			ath10k_htt_rx_h_mpdu(ar, &amsdu, status);
			ath10k_htt_rx_h_deliver(ar, &amsdu, status);
			break;
		case -EAGAIN:
			/* fall through */
		default:
			/* Should not happen. */
			ath10k_warn(ar, "failed to extract amsdu: %d\n", ret);
			htt->rx_confused = true;
			__skb_queue_purge(&list);
			return;
		}
	}

	tasklet_schedule(&htt->rx_replenish_task);
}

void ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
{
	struct ath10k_htt *htt = &ar->htt;
	struct htt_resp *resp = (struct htt_resp *)skb->data;
	enum htt_t2h_msg_type type;

	/* confirm alignment */
	if (!IS_ALIGNED((unsigned long)skb->data, 4))
		ath10k_warn(ar, "unaligned htt message, expect trouble\n");

	ath10k_dbg(ar, ATH10K_DBG_HTT, "htt rx, msg_type: 0x%0X\n",
		   resp->hdr.msg_type);

	if (resp->hdr.msg_type >= ar->htt.t2h_msg_types_max) {
		ath10k_dbg(ar, ATH10K_DBG_HTT, "htt rx, unsupported msg_type: 0x%0X\n max: 0x%0X",
			   resp->hdr.msg_type, ar->htt.t2h_msg_types_max);
		dev_kfree_skb_any(skb);
		return;
	}
	type = ar->htt.t2h_msg_types[resp->hdr.msg_type];

	switch (type) {
	case HTT_T2H_MSG_TYPE_VERSION_CONF: {
		htt->target_version_major = resp->ver_resp.major;
		htt->target_version_minor = resp->ver_resp.minor;
		complete(&htt->target_version_received);
		break;
	}
	case HTT_T2H_MSG_TYPE_RX_IND:
		spin_lock_bh(&htt->rx_ring.lock);
		__skb_queue_tail(&htt->rx_compl_q, skb);
		spin_unlock_bh(&htt->rx_ring.lock);
		tasklet_schedule(&htt->txrx_compl_task);
		return;
	case HTT_T2H_MSG_TYPE_PEER_MAP: {
		struct htt_peer_map_event ev = {
			.vdev_id = resp->peer_map.vdev_id,
			.peer_id = __le16_to_cpu(resp->peer_map.peer_id),
		};
		memcpy(ev.addr, resp->peer_map.addr, sizeof(ev.addr));
		ath10k_peer_map_event(htt, &ev);
		break;
	}
	case HTT_T2H_MSG_TYPE_PEER_UNMAP: {
		struct htt_peer_unmap_event ev = {
			.peer_id = __le16_to_cpu(resp->peer_unmap.peer_id),
		};
		ath10k_peer_unmap_event(htt, &ev);
		break;
	}
	case HTT_T2H_MSG_TYPE_MGMT_TX_COMPLETION: {
		struct htt_tx_done tx_done = {};
		int status = __le32_to_cpu(resp->mgmt_tx_completion.status);

		tx_done.msdu_id =
			__le32_to_cpu(resp->mgmt_tx_completion.desc_id);

		switch (status) {
		case HTT_MGMT_TX_STATUS_OK:
			tx_done.success = true;
			break;
		case HTT_MGMT_TX_STATUS_RETRY:
			tx_done.no_ack = true;
			break;
		case HTT_MGMT_TX_STATUS_DROP:
			tx_done.discard = true;
			break;
		}

		ath10k_txrx_tx_unref(htt, &tx_done);
		break;
	}
	case HTT_T2H_MSG_TYPE_TX_COMPL_IND:
		skb_queue_tail(&htt->tx_compl_q, skb);
		tasklet_schedule(&htt->txrx_compl_task);
		return;
	case HTT_T2H_MSG_TYPE_SEC_IND: {
		struct ath10k *ar = htt->ar;
		struct htt_security_indication *ev = &resp->security_indication;

		ath10k_dbg(ar, ATH10K_DBG_HTT,
			   "sec ind peer_id %d unicast %d type %d\n",
			  __le16_to_cpu(ev->peer_id),
			  !!(ev->flags & HTT_SECURITY_IS_UNICAST),
			  MS(ev->flags, HTT_SECURITY_TYPE));
		complete(&ar->install_key_done);
		break;
	}
	case HTT_T2H_MSG_TYPE_RX_FRAG_IND: {
		ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt event: ",
				skb->data, skb->len);
		ath10k_htt_rx_frag_handler(htt, &resp->rx_frag_ind);
		break;
	}
	case HTT_T2H_MSG_TYPE_TEST:
		break;
	case HTT_T2H_MSG_TYPE_STATS_CONF:
		trace_ath10k_htt_stats(ar, skb->data, skb->len);
		break;
	case HTT_T2H_MSG_TYPE_TX_INSPECT_IND:
		/* Firmware can return tx frames if it's unable to fully
		 * process them and suspects host may be able to fix it. ath10k
		 * sends all tx frames as already inspected so this shouldn't
		 * happen unless fw has a bug.
		 */
		ath10k_warn(ar, "received an unexpected htt tx inspect event\n");
		break;
	case HTT_T2H_MSG_TYPE_RX_ADDBA:
		ath10k_htt_rx_addba(ar, resp);
		break;
	case HTT_T2H_MSG_TYPE_RX_DELBA:
		ath10k_htt_rx_delba(ar, resp);
		break;
	case HTT_T2H_MSG_TYPE_PKTLOG: {
		struct ath10k_pktlog_hdr *hdr =
			(struct ath10k_pktlog_hdr *)resp->pktlog_msg.payload;

		trace_ath10k_htt_pktlog(ar, resp->pktlog_msg.payload,
					sizeof(*hdr) +
					__le16_to_cpu(hdr->size));
		break;
	}
	case HTT_T2H_MSG_TYPE_RX_FLUSH: {
		/* Ignore this event because mac80211 takes care of Rx
		 * aggregation reordering.
		 */
		break;
	}
	case HTT_T2H_MSG_TYPE_RX_IN_ORD_PADDR_IND: {
		spin_lock_bh(&htt->rx_ring.lock);
		__skb_queue_tail(&htt->rx_in_ord_compl_q, skb);
		spin_unlock_bh(&htt->rx_ring.lock);
		tasklet_schedule(&htt->txrx_compl_task);
		return;
	}
	case HTT_T2H_MSG_TYPE_TX_CREDIT_UPDATE_IND:
		break;
	case HTT_T2H_MSG_TYPE_CHAN_CHANGE:
		break;
	case HTT_T2H_MSG_TYPE_AGGR_CONF:
		break;
	case HTT_T2H_MSG_TYPE_EN_STATS:
	case HTT_T2H_MSG_TYPE_TX_FETCH_IND:
	case HTT_T2H_MSG_TYPE_TX_FETCH_CONF:
	case HTT_T2H_MSG_TYPE_TX_LOW_LATENCY_IND:
	default:
		ath10k_warn(ar, "htt event (%d) not handled\n",
			    resp->hdr.msg_type);
		ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt event: ",
				skb->data, skb->len);
		break;
	};

	/* Free the indication buffer */
	dev_kfree_skb_any(skb);
}

static void ath10k_htt_txrx_compl_task(unsigned long ptr)
{
	struct ath10k_htt *htt = (struct ath10k_htt *)ptr;
	struct ath10k *ar = htt->ar;
	struct htt_resp *resp;
	struct sk_buff *skb;

	while ((skb = skb_dequeue(&htt->tx_compl_q))) {
		ath10k_htt_rx_frm_tx_compl(htt->ar, skb);
		dev_kfree_skb_any(skb);
	}

	spin_lock_bh(&htt->rx_ring.lock);
	while ((skb = __skb_dequeue(&htt->rx_compl_q))) {
		resp = (struct htt_resp *)skb->data;
		ath10k_htt_rx_handler(htt, &resp->rx_ind);
		dev_kfree_skb_any(skb);
	}

	while ((skb = __skb_dequeue(&htt->rx_in_ord_compl_q))) {
		ath10k_htt_rx_in_ord_ind(ar, skb);
		dev_kfree_skb_any(skb);
	}
	spin_unlock_bh(&htt->rx_ring.lock);
}