aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/intel/ice/ice_ptp.c
blob: 05cc5870e4efb52b01ef1cf649b4bf318d8e498d (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
// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2021, Intel Corporation. */

#include "ice.h"
#include "ice_lib.h"

#define E810_OUT_PROP_DELAY_NS 1

/**
 * ice_set_tx_tstamp - Enable or disable Tx timestamping
 * @pf: The PF pointer to search in
 * @on: bool value for whether timestamps are enabled or disabled
 */
static void ice_set_tx_tstamp(struct ice_pf *pf, bool on)
{
	struct ice_vsi *vsi;
	u32 val;
	u16 i;

	vsi = ice_get_main_vsi(pf);
	if (!vsi)
		return;

	/* Set the timestamp enable flag for all the Tx rings */
	ice_for_each_txq(vsi, i) {
		if (!vsi->tx_rings[i])
			continue;
		vsi->tx_rings[i]->ptp_tx = on;
	}

	/* Configure the Tx timestamp interrupt */
	val = rd32(&pf->hw, PFINT_OICR_ENA);
	if (on)
		val |= PFINT_OICR_TSYN_TX_M;
	else
		val &= ~PFINT_OICR_TSYN_TX_M;
	wr32(&pf->hw, PFINT_OICR_ENA, val);
}

/**
 * ice_set_rx_tstamp - Enable or disable Rx timestamping
 * @pf: The PF pointer to search in
 * @on: bool value for whether timestamps are enabled or disabled
 */
static void ice_set_rx_tstamp(struct ice_pf *pf, bool on)
{
	struct ice_vsi *vsi;
	u16 i;

	vsi = ice_get_main_vsi(pf);
	if (!vsi)
		return;

	/* Set the timestamp flag for all the Rx rings */
	ice_for_each_rxq(vsi, i) {
		if (!vsi->rx_rings[i])
			continue;
		vsi->rx_rings[i]->ptp_rx = on;
	}
}

/**
 * ice_ptp_cfg_timestamp - Configure timestamp for init/deinit
 * @pf: Board private structure
 * @ena: bool value to enable or disable time stamp
 *
 * This function will configure timestamping during PTP initialization
 * and deinitialization
 */
static void ice_ptp_cfg_timestamp(struct ice_pf *pf, bool ena)
{
	ice_set_tx_tstamp(pf, ena);
	ice_set_rx_tstamp(pf, ena);

	if (ena) {
		pf->ptp.tstamp_config.rx_filter = HWTSTAMP_FILTER_ALL;
		pf->ptp.tstamp_config.tx_type = HWTSTAMP_TX_ON;
	} else {
		pf->ptp.tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
		pf->ptp.tstamp_config.tx_type = HWTSTAMP_TX_OFF;
	}
}

/**
 * ice_get_ptp_clock_index - Get the PTP clock index
 * @pf: the PF pointer
 *
 * Determine the clock index of the PTP clock associated with this device. If
 * this is the PF controlling the clock, just use the local access to the
 * clock device pointer.
 *
 * Otherwise, read from the driver shared parameters to determine the clock
 * index value.
 *
 * Returns: the index of the PTP clock associated with this device, or -1 if
 * there is no associated clock.
 */
int ice_get_ptp_clock_index(struct ice_pf *pf)
{
	struct device *dev = ice_pf_to_dev(pf);
	enum ice_aqc_driver_params param_idx;
	struct ice_hw *hw = &pf->hw;
	u8 tmr_idx;
	u32 value;
	int err;

	/* Use the ptp_clock structure if we're the main PF */
	if (pf->ptp.clock)
		return ptp_clock_index(pf->ptp.clock);

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_assoc;
	if (!tmr_idx)
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR0;
	else
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR1;

	err = ice_aq_get_driver_param(hw, param_idx, &value, NULL);
	if (err) {
		dev_err(dev, "Failed to read PTP clock index parameter, err %d aq_err %s\n",
			err, ice_aq_str(hw->adminq.sq_last_status));
		return -1;
	}

	/* The PTP clock index is an integer, and will be between 0 and
	 * INT_MAX. The highest bit of the driver shared parameter is used to
	 * indicate whether or not the currently stored clock index is valid.
	 */
	if (!(value & PTP_SHARED_CLK_IDX_VALID))
		return -1;

	return value & ~PTP_SHARED_CLK_IDX_VALID;
}

/**
 * ice_set_ptp_clock_index - Set the PTP clock index
 * @pf: the PF pointer
 *
 * Set the PTP clock index for this device into the shared driver parameters,
 * so that other PFs associated with this device can read it.
 *
 * If the PF is unable to store the clock index, it will log an error, but
 * will continue operating PTP.
 */
static void ice_set_ptp_clock_index(struct ice_pf *pf)
{
	struct device *dev = ice_pf_to_dev(pf);
	enum ice_aqc_driver_params param_idx;
	struct ice_hw *hw = &pf->hw;
	u8 tmr_idx;
	u32 value;
	int err;

	if (!pf->ptp.clock)
		return;

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_assoc;
	if (!tmr_idx)
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR0;
	else
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR1;

	value = (u32)ptp_clock_index(pf->ptp.clock);
	if (value > INT_MAX) {
		dev_err(dev, "PTP Clock index is too large to store\n");
		return;
	}
	value |= PTP_SHARED_CLK_IDX_VALID;

	err = ice_aq_set_driver_param(hw, param_idx, value, NULL);
	if (err) {
		dev_err(dev, "Failed to set PTP clock index parameter, err %d aq_err %s\n",
			err, ice_aq_str(hw->adminq.sq_last_status));
	}
}

/**
 * ice_clear_ptp_clock_index - Clear the PTP clock index
 * @pf: the PF pointer
 *
 * Clear the PTP clock index for this device. Must be called when
 * unregistering the PTP clock, in order to ensure other PFs stop reporting
 * a clock object that no longer exists.
 */
static void ice_clear_ptp_clock_index(struct ice_pf *pf)
{
	struct device *dev = ice_pf_to_dev(pf);
	enum ice_aqc_driver_params param_idx;
	struct ice_hw *hw = &pf->hw;
	u8 tmr_idx;
	int err;

	/* Do not clear the index if we don't own the timer */
	if (!hw->func_caps.ts_func_info.src_tmr_owned)
		return;

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_assoc;
	if (!tmr_idx)
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR0;
	else
		param_idx = ICE_AQC_DRIVER_PARAM_CLK_IDX_TMR1;

	err = ice_aq_set_driver_param(hw, param_idx, 0, NULL);
	if (err) {
		dev_dbg(dev, "Failed to clear PTP clock index parameter, err %d aq_err %s\n",
			err, ice_aq_str(hw->adminq.sq_last_status));
	}
}

/**
 * ice_ptp_read_src_clk_reg - Read the source clock register
 * @pf: Board private structure
 * @sts: Optional parameter for holding a pair of system timestamps from
 *       the system clock. Will be ignored if NULL is given.
 */
static u64
ice_ptp_read_src_clk_reg(struct ice_pf *pf, struct ptp_system_timestamp *sts)
{
	struct ice_hw *hw = &pf->hw;
	u32 hi, lo, lo2;
	u8 tmr_idx;

	tmr_idx = ice_get_ptp_src_clock_index(hw);
	/* Read the system timestamp pre PHC read */
	ptp_read_system_prets(sts);

	lo = rd32(hw, GLTSYN_TIME_L(tmr_idx));

	/* Read the system timestamp post PHC read */
	ptp_read_system_postts(sts);

	hi = rd32(hw, GLTSYN_TIME_H(tmr_idx));
	lo2 = rd32(hw, GLTSYN_TIME_L(tmr_idx));

	if (lo2 < lo) {
		/* if TIME_L rolled over read TIME_L again and update
		 * system timestamps
		 */
		ptp_read_system_prets(sts);
		lo = rd32(hw, GLTSYN_TIME_L(tmr_idx));
		ptp_read_system_postts(sts);
		hi = rd32(hw, GLTSYN_TIME_H(tmr_idx));
	}

	return ((u64)hi << 32) | lo;
}

/**
 * ice_ptp_update_cached_phctime - Update the cached PHC time values
 * @pf: Board specific private structure
 *
 * This function updates the system time values which are cached in the PF
 * structure and the Rx rings.
 *
 * This function must be called periodically to ensure that the cached value
 * is never more than 2 seconds old. It must also be called whenever the PHC
 * time has been changed.
 */
static void ice_ptp_update_cached_phctime(struct ice_pf *pf)
{
	u64 systime;
	int i;

	/* Read the current PHC time */
	systime = ice_ptp_read_src_clk_reg(pf, NULL);

	/* Update the cached PHC time stored in the PF structure */
	WRITE_ONCE(pf->ptp.cached_phc_time, systime);

	ice_for_each_vsi(pf, i) {
		struct ice_vsi *vsi = pf->vsi[i];
		int j;

		if (!vsi)
			continue;

		if (vsi->type != ICE_VSI_PF)
			continue;

		ice_for_each_rxq(vsi, j) {
			if (!vsi->rx_rings[j])
				continue;
			WRITE_ONCE(vsi->rx_rings[j]->cached_phctime, systime);
		}
	}
}

/**
 * ice_ptp_extend_32b_ts - Convert a 32b nanoseconds timestamp to 64b
 * @cached_phc_time: recently cached copy of PHC time
 * @in_tstamp: Ingress/egress 32b nanoseconds timestamp value
 *
 * Hardware captures timestamps which contain only 32 bits of nominal
 * nanoseconds, as opposed to the 64bit timestamps that the stack expects.
 * Note that the captured timestamp values may be 40 bits, but the lower
 * 8 bits are sub-nanoseconds and generally discarded.
 *
 * Extend the 32bit nanosecond timestamp using the following algorithm and
 * assumptions:
 *
 * 1) have a recently cached copy of the PHC time
 * 2) assume that the in_tstamp was captured 2^31 nanoseconds (~2.1
 *    seconds) before or after the PHC time was captured.
 * 3) calculate the delta between the cached time and the timestamp
 * 4) if the delta is smaller than 2^31 nanoseconds, then the timestamp was
 *    captured after the PHC time. In this case, the full timestamp is just
 *    the cached PHC time plus the delta.
 * 5) otherwise, if the delta is larger than 2^31 nanoseconds, then the
 *    timestamp was captured *before* the PHC time, i.e. because the PHC
 *    cache was updated after the timestamp was captured by hardware. In this
 *    case, the full timestamp is the cached time minus the inverse delta.
 *
 * This algorithm works even if the PHC time was updated after a Tx timestamp
 * was requested, but before the Tx timestamp event was reported from
 * hardware.
 *
 * This calculation primarily relies on keeping the cached PHC time up to
 * date. If the timestamp was captured more than 2^31 nanoseconds after the
 * PHC time, it is possible that the lower 32bits of PHC time have
 * overflowed more than once, and we might generate an incorrect timestamp.
 *
 * This is prevented by (a) periodically updating the cached PHC time once
 * a second, and (b) discarding any Tx timestamp packet if it has waited for
 * a timestamp for more than one second.
 */
static u64 ice_ptp_extend_32b_ts(u64 cached_phc_time, u32 in_tstamp)
{
	u32 delta, phc_time_lo;
	u64 ns;

	/* Extract the lower 32 bits of the PHC time */
	phc_time_lo = (u32)cached_phc_time;

	/* Calculate the delta between the lower 32bits of the cached PHC
	 * time and the in_tstamp value
	 */
	delta = (in_tstamp - phc_time_lo);

	/* Do not assume that the in_tstamp is always more recent than the
	 * cached PHC time. If the delta is large, it indicates that the
	 * in_tstamp was taken in the past, and should be converted
	 * forward.
	 */
	if (delta > (U32_MAX / 2)) {
		/* reverse the delta calculation here */
		delta = (phc_time_lo - in_tstamp);
		ns = cached_phc_time - delta;
	} else {
		ns = cached_phc_time + delta;
	}

	return ns;
}

/**
 * ice_ptp_extend_40b_ts - Convert a 40b timestamp to 64b nanoseconds
 * @pf: Board private structure
 * @in_tstamp: Ingress/egress 40b timestamp value
 *
 * The Tx and Rx timestamps are 40 bits wide, including 32 bits of nominal
 * nanoseconds, 7 bits of sub-nanoseconds, and a valid bit.
 *
 *  *--------------------------------------------------------------*
 *  | 32 bits of nanoseconds | 7 high bits of sub ns underflow | v |
 *  *--------------------------------------------------------------*
 *
 * The low bit is an indicator of whether the timestamp is valid. The next
 * 7 bits are a capture of the upper 7 bits of the sub-nanosecond underflow,
 * and the remaining 32 bits are the lower 32 bits of the PHC timer.
 *
 * It is assumed that the caller verifies the timestamp is valid prior to
 * calling this function.
 *
 * Extract the 32bit nominal nanoseconds and extend them. Use the cached PHC
 * time stored in the device private PTP structure as the basis for timestamp
 * extension.
 *
 * See ice_ptp_extend_32b_ts for a detailed explanation of the extension
 * algorithm.
 */
static u64 ice_ptp_extend_40b_ts(struct ice_pf *pf, u64 in_tstamp)
{
	const u64 mask = GENMASK_ULL(31, 0);

	return ice_ptp_extend_32b_ts(pf->ptp.cached_phc_time,
				     (in_tstamp >> 8) & mask);
}

/**
 * ice_ptp_read_time - Read the time from the device
 * @pf: Board private structure
 * @ts: timespec structure to hold the current time value
 * @sts: Optional parameter for holding a pair of system timestamps from
 *       the system clock. Will be ignored if NULL is given.
 *
 * This function reads the source clock registers and stores them in a timespec.
 * However, since the registers are 64 bits of nanoseconds, we must convert the
 * result to a timespec before we can return.
 */
static void
ice_ptp_read_time(struct ice_pf *pf, struct timespec64 *ts,
		  struct ptp_system_timestamp *sts)
{
	u64 time_ns = ice_ptp_read_src_clk_reg(pf, sts);

	*ts = ns_to_timespec64(time_ns);
}

/**
 * ice_ptp_write_init - Set PHC time to provided value
 * @pf: Board private structure
 * @ts: timespec structure that holds the new time value
 *
 * Set the PHC time to the specified time provided in the timespec.
 */
static int ice_ptp_write_init(struct ice_pf *pf, struct timespec64 *ts)
{
	u64 ns = timespec64_to_ns(ts);
	struct ice_hw *hw = &pf->hw;

	return ice_ptp_init_time(hw, ns);
}

/**
 * ice_ptp_write_adj - Adjust PHC clock time atomically
 * @pf: Board private structure
 * @adj: Adjustment in nanoseconds
 *
 * Perform an atomic adjustment of the PHC time by the specified number of
 * nanoseconds.
 */
static int ice_ptp_write_adj(struct ice_pf *pf, s32 adj)
{
	struct ice_hw *hw = &pf->hw;

	return ice_ptp_adj_clock(hw, adj);
}

/**
 * ice_ptp_adjfine - Adjust clock increment rate
 * @info: the driver's PTP info structure
 * @scaled_ppm: Parts per million with 16-bit fractional field
 *
 * Adjust the frequency of the clock by the indicated scaled ppm from the
 * base frequency.
 */
static int ice_ptp_adjfine(struct ptp_clock_info *info, long scaled_ppm)
{
	struct ice_pf *pf = ptp_info_to_pf(info);
	u64 freq, divisor = 1000000ULL;
	struct ice_hw *hw = &pf->hw;
	s64 incval, diff;
	int neg_adj = 0;
	int err;

	incval = ICE_PTP_NOMINAL_INCVAL_E810;

	if (scaled_ppm < 0) {
		neg_adj = 1;
		scaled_ppm = -scaled_ppm;
	}

	while ((u64)scaled_ppm > div_u64(U64_MAX, incval)) {
		/* handle overflow by scaling down the scaled_ppm and
		 * the divisor, losing some precision
		 */
		scaled_ppm >>= 2;
		divisor >>= 2;
	}

	freq = (incval * (u64)scaled_ppm) >> 16;
	diff = div_u64(freq, divisor);

	if (neg_adj)
		incval -= diff;
	else
		incval += diff;

	err = ice_ptp_write_incval_locked(hw, incval);
	if (err) {
		dev_err(ice_pf_to_dev(pf), "PTP failed to set incval, err %d\n",
			err);
		return -EIO;
	}

	return 0;
}

/**
 * ice_ptp_extts_work - Workqueue task function
 * @work: external timestamp work structure
 *
 * Service for PTP external clock event
 */
static void ice_ptp_extts_work(struct kthread_work *work)
{
	struct ice_ptp *ptp = container_of(work, struct ice_ptp, extts_work);
	struct ice_pf *pf = container_of(ptp, struct ice_pf, ptp);
	struct ptp_clock_event event;
	struct ice_hw *hw = &pf->hw;
	u8 chan, tmr_idx;
	u32 hi, lo;

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;
	/* Event time is captured by one of the two matched registers
	 *      GLTSYN_EVNT_L: 32 LSB of sampled time event
	 *      GLTSYN_EVNT_H: 32 MSB of sampled time event
	 * Event is defined in GLTSYN_EVNT_0 register
	 */
	for (chan = 0; chan < GLTSYN_EVNT_H_IDX_MAX; chan++) {
		/* Check if channel is enabled */
		if (pf->ptp.ext_ts_irq & (1 << chan)) {
			lo = rd32(hw, GLTSYN_EVNT_L(chan, tmr_idx));
			hi = rd32(hw, GLTSYN_EVNT_H(chan, tmr_idx));
			event.timestamp = (((u64)hi) << 32) | lo;
			event.type = PTP_CLOCK_EXTTS;
			event.index = chan;

			/* Fire event */
			ptp_clock_event(pf->ptp.clock, &event);
			pf->ptp.ext_ts_irq &= ~(1 << chan);
		}
	}
}

/**
 * ice_ptp_cfg_extts - Configure EXTTS pin and channel
 * @pf: Board private structure
 * @ena: true to enable; false to disable
 * @chan: GPIO channel (0-3)
 * @gpio_pin: GPIO pin
 * @extts_flags: request flags from the ptp_extts_request.flags
 */
static int
ice_ptp_cfg_extts(struct ice_pf *pf, bool ena, unsigned int chan, u32 gpio_pin,
		  unsigned int extts_flags)
{
	u32 func, aux_reg, gpio_reg, irq_reg;
	struct ice_hw *hw = &pf->hw;
	u8 tmr_idx;

	if (chan > (unsigned int)pf->ptp.info.n_ext_ts)
		return -EINVAL;

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;

	irq_reg = rd32(hw, PFINT_OICR_ENA);

	if (ena) {
		/* Enable the interrupt */
		irq_reg |= PFINT_OICR_TSYN_EVNT_M;
		aux_reg = GLTSYN_AUX_IN_0_INT_ENA_M;

#define GLTSYN_AUX_IN_0_EVNTLVL_RISING_EDGE	BIT(0)
#define GLTSYN_AUX_IN_0_EVNTLVL_FALLING_EDGE	BIT(1)

		/* set event level to requested edge */
		if (extts_flags & PTP_FALLING_EDGE)
			aux_reg |= GLTSYN_AUX_IN_0_EVNTLVL_FALLING_EDGE;
		if (extts_flags & PTP_RISING_EDGE)
			aux_reg |= GLTSYN_AUX_IN_0_EVNTLVL_RISING_EDGE;

		/* Write GPIO CTL reg.
		 * 0x1 is input sampled by EVENT register(channel)
		 * + num_in_channels * tmr_idx
		 */
		func = 1 + chan + (tmr_idx * 3);
		gpio_reg = ((func << GLGEN_GPIO_CTL_PIN_FUNC_S) &
			    GLGEN_GPIO_CTL_PIN_FUNC_M);
		pf->ptp.ext_ts_chan |= (1 << chan);
	} else {
		/* clear the values we set to reset defaults */
		aux_reg = 0;
		gpio_reg = 0;
		pf->ptp.ext_ts_chan &= ~(1 << chan);
		if (!pf->ptp.ext_ts_chan)
			irq_reg &= ~PFINT_OICR_TSYN_EVNT_M;
	}

	wr32(hw, PFINT_OICR_ENA, irq_reg);
	wr32(hw, GLTSYN_AUX_IN(chan, tmr_idx), aux_reg);
	wr32(hw, GLGEN_GPIO_CTL(gpio_pin), gpio_reg);

	return 0;
}

/**
 * ice_ptp_cfg_clkout - Configure clock to generate periodic wave
 * @pf: Board private structure
 * @chan: GPIO channel (0-3)
 * @config: desired periodic clk configuration. NULL will disable channel
 * @store: If set to true the values will be stored
 *
 * Configure the internal clock generator modules to generate the clock wave of
 * specified period.
 */
static int ice_ptp_cfg_clkout(struct ice_pf *pf, unsigned int chan,
			      struct ice_perout_channel *config, bool store)
{
	u64 current_time, period, start_time, phase;
	struct ice_hw *hw = &pf->hw;
	u32 func, val, gpio_pin;
	u8 tmr_idx;

	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;

	/* 0. Reset mode & out_en in AUX_OUT */
	wr32(hw, GLTSYN_AUX_OUT(chan, tmr_idx), 0);

	/* If we're disabling the output, clear out CLKO and TGT and keep
	 * output level low
	 */
	if (!config || !config->ena) {
		wr32(hw, GLTSYN_CLKO(chan, tmr_idx), 0);
		wr32(hw, GLTSYN_TGT_L(chan, tmr_idx), 0);
		wr32(hw, GLTSYN_TGT_H(chan, tmr_idx), 0);

		val = GLGEN_GPIO_CTL_PIN_DIR_M;
		gpio_pin = pf->ptp.perout_channels[chan].gpio_pin;
		wr32(hw, GLGEN_GPIO_CTL(gpio_pin), val);

		/* Store the value if requested */
		if (store)
			memset(&pf->ptp.perout_channels[chan], 0,
			       sizeof(struct ice_perout_channel));

		return 0;
	}
	period = config->period;
	start_time = config->start_time;
	div64_u64_rem(start_time, period, &phase);
	gpio_pin = config->gpio_pin;

	/* 1. Write clkout with half of required period value */
	if (period & 0x1) {
		dev_err(ice_pf_to_dev(pf), "CLK Period must be an even value\n");
		goto err;
	}

	period >>= 1;

	/* For proper operation, the GLTSYN_CLKO must be larger than clock tick
	 */
#define MIN_PULSE 3
	if (period <= MIN_PULSE || period > U32_MAX) {
		dev_err(ice_pf_to_dev(pf), "CLK Period must be > %d && < 2^33",
			MIN_PULSE * 2);
		goto err;
	}

	wr32(hw, GLTSYN_CLKO(chan, tmr_idx), lower_32_bits(period));

	/* Allow time for programming before start_time is hit */
	current_time = ice_ptp_read_src_clk_reg(pf, NULL);

	/* if start time is in the past start the timer at the nearest second
	 * maintaining phase
	 */
	if (start_time < current_time)
		start_time = div64_u64(current_time + NSEC_PER_SEC - 1,
				       NSEC_PER_SEC) * NSEC_PER_SEC + phase;

	start_time -= E810_OUT_PROP_DELAY_NS;

	/* 2. Write TARGET time */
	wr32(hw, GLTSYN_TGT_L(chan, tmr_idx), lower_32_bits(start_time));
	wr32(hw, GLTSYN_TGT_H(chan, tmr_idx), upper_32_bits(start_time));

	/* 3. Write AUX_OUT register */
	val = GLTSYN_AUX_OUT_0_OUT_ENA_M | GLTSYN_AUX_OUT_0_OUTMOD_M;
	wr32(hw, GLTSYN_AUX_OUT(chan, tmr_idx), val);

	/* 4. write GPIO CTL reg */
	func = 8 + chan + (tmr_idx * 4);
	val = GLGEN_GPIO_CTL_PIN_DIR_M |
	      ((func << GLGEN_GPIO_CTL_PIN_FUNC_S) & GLGEN_GPIO_CTL_PIN_FUNC_M);
	wr32(hw, GLGEN_GPIO_CTL(gpio_pin), val);

	/* Store the value if requested */
	if (store) {
		memcpy(&pf->ptp.perout_channels[chan], config,
		       sizeof(struct ice_perout_channel));
		pf->ptp.perout_channels[chan].start_time = phase;
	}

	return 0;
err:
	dev_err(ice_pf_to_dev(pf), "PTP failed to cfg per_clk\n");
	return -EFAULT;
}

/**
 * ice_ptp_disable_all_clkout - Disable all currently configured outputs
 * @pf: pointer to the PF structure
 *
 * Disable all currently configured clock outputs. This is necessary before
 * certain changes to the PTP hardware clock. Use ice_ptp_enable_all_clkout to
 * re-enable the clocks again.
 */
static void ice_ptp_disable_all_clkout(struct ice_pf *pf)
{
	uint i;

	for (i = 0; i < pf->ptp.info.n_per_out; i++)
		if (pf->ptp.perout_channels[i].ena)
			ice_ptp_cfg_clkout(pf, i, NULL, false);
}

/**
 * ice_ptp_enable_all_clkout - Enable all configured periodic clock outputs
 * @pf: pointer to the PF structure
 *
 * Enable all currently configured clock outputs. Use this after
 * ice_ptp_disable_all_clkout to reconfigure the output signals according to
 * their configuration.
 */
static void ice_ptp_enable_all_clkout(struct ice_pf *pf)
{
	uint i;

	for (i = 0; i < pf->ptp.info.n_per_out; i++)
		if (pf->ptp.perout_channels[i].ena)
			ice_ptp_cfg_clkout(pf, i, &pf->ptp.perout_channels[i],
					   false);
}

/**
 * ice_ptp_gpio_enable_e810 - Enable/disable ancillary features of PHC
 * @info: the driver's PTP info structure
 * @rq: The requested feature to change
 * @on: Enable/disable flag
 */
static int
ice_ptp_gpio_enable_e810(struct ptp_clock_info *info,
			 struct ptp_clock_request *rq, int on)
{
	struct ice_pf *pf = ptp_info_to_pf(info);
	struct ice_perout_channel clk_cfg = {0};
	unsigned int chan;
	u32 gpio_pin;
	int err;

	switch (rq->type) {
	case PTP_CLK_REQ_PEROUT:
		chan = rq->perout.index;
		if (chan == PPS_CLK_GEN_CHAN)
			clk_cfg.gpio_pin = PPS_PIN_INDEX;
		else
			clk_cfg.gpio_pin = chan;

		clk_cfg.period = ((rq->perout.period.sec * NSEC_PER_SEC) +
				   rq->perout.period.nsec);
		clk_cfg.start_time = ((rq->perout.start.sec * NSEC_PER_SEC) +
				       rq->perout.start.nsec);
		clk_cfg.ena = !!on;

		err = ice_ptp_cfg_clkout(pf, chan, &clk_cfg, true);
		break;
	case PTP_CLK_REQ_EXTTS:
		chan = rq->extts.index;
		gpio_pin = chan;

		err = ice_ptp_cfg_extts(pf, !!on, chan, gpio_pin,
					rq->extts.flags);
		break;
	default:
		return -EOPNOTSUPP;
	}

	return err;
}

/**
 * ice_ptp_gettimex64 - Get the time of the clock
 * @info: the driver's PTP info structure
 * @ts: timespec64 structure to hold the current time value
 * @sts: Optional parameter for holding a pair of system timestamps from
 *       the system clock. Will be ignored if NULL is given.
 *
 * Read the device clock and return the correct value on ns, after converting it
 * into a timespec struct.
 */
static int
ice_ptp_gettimex64(struct ptp_clock_info *info, struct timespec64 *ts,
		   struct ptp_system_timestamp *sts)
{
	struct ice_pf *pf = ptp_info_to_pf(info);
	struct ice_hw *hw = &pf->hw;

	if (!ice_ptp_lock(hw)) {
		dev_err(ice_pf_to_dev(pf), "PTP failed to get time\n");
		return -EBUSY;
	}

	ice_ptp_read_time(pf, ts, sts);
	ice_ptp_unlock(hw);

	return 0;
}

/**
 * ice_ptp_settime64 - Set the time of the clock
 * @info: the driver's PTP info structure
 * @ts: timespec64 structure that holds the new time value
 *
 * Set the device clock to the user input value. The conversion from timespec
 * to ns happens in the write function.
 */
static int
ice_ptp_settime64(struct ptp_clock_info *info, const struct timespec64 *ts)
{
	struct ice_pf *pf = ptp_info_to_pf(info);
	struct timespec64 ts64 = *ts;
	struct ice_hw *hw = &pf->hw;
	int err;

	if (!ice_ptp_lock(hw)) {
		err = -EBUSY;
		goto exit;
	}

	/* Disable periodic outputs */
	ice_ptp_disable_all_clkout(pf);

	err = ice_ptp_write_init(pf, &ts64);
	ice_ptp_unlock(hw);

	if (!err)
		ice_ptp_update_cached_phctime(pf);

	/* Reenable periodic outputs */
	ice_ptp_enable_all_clkout(pf);
exit:
	if (err) {
		dev_err(ice_pf_to_dev(pf), "PTP failed to set time %d\n", err);
		return err;
	}

	return 0;
}

/**
 * ice_ptp_adjtime_nonatomic - Do a non-atomic clock adjustment
 * @info: the driver's PTP info structure
 * @delta: Offset in nanoseconds to adjust the time by
 */
static int ice_ptp_adjtime_nonatomic(struct ptp_clock_info *info, s64 delta)
{
	struct timespec64 now, then;

	then = ns_to_timespec64(delta);
	ice_ptp_gettimex64(info, &now, NULL);
	now = timespec64_add(now, then);

	return ice_ptp_settime64(info, (const struct timespec64 *)&now);
}

/**
 * ice_ptp_adjtime - Adjust the time of the clock by the indicated delta
 * @info: the driver's PTP info structure
 * @delta: Offset in nanoseconds to adjust the time by
 */
static int ice_ptp_adjtime(struct ptp_clock_info *info, s64 delta)
{
	struct ice_pf *pf = ptp_info_to_pf(info);
	struct ice_hw *hw = &pf->hw;
	struct device *dev;
	int err;

	dev = ice_pf_to_dev(pf);

	/* Hardware only supports atomic adjustments using signed 32-bit
	 * integers. For any adjustment outside this range, perform
	 * a non-atomic get->adjust->set flow.
	 */
	if (delta > S32_MAX || delta < S32_MIN) {
		dev_dbg(dev, "delta = %lld, adjtime non-atomic\n", delta);
		return ice_ptp_adjtime_nonatomic(info, delta);
	}

	if (!ice_ptp_lock(hw)) {
		dev_err(dev, "PTP failed to acquire semaphore in adjtime\n");
		return -EBUSY;
	}

	/* Disable periodic outputs */
	ice_ptp_disable_all_clkout(pf);

	err = ice_ptp_write_adj(pf, delta);

	/* Reenable periodic outputs */
	ice_ptp_enable_all_clkout(pf);

	ice_ptp_unlock(hw);

	if (err) {
		dev_err(dev, "PTP failed to adjust time, err %d\n", err);
		return err;
	}

	ice_ptp_update_cached_phctime(pf);

	return 0;
}

/**
 * ice_ptp_get_ts_config - ioctl interface to read the timestamping config
 * @pf: Board private structure
 * @ifr: ioctl data
 *
 * Copy the timestamping config to user buffer
 */
int ice_ptp_get_ts_config(struct ice_pf *pf, struct ifreq *ifr)
{
	struct hwtstamp_config *config;

	if (!test_bit(ICE_FLAG_PTP, pf->flags))
		return -EIO;

	config = &pf->ptp.tstamp_config;

	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
		-EFAULT : 0;
}

/**
 * ice_ptp_set_timestamp_mode - Setup driver for requested timestamp mode
 * @pf: Board private structure
 * @config: hwtstamp settings requested or saved
 */
static int
ice_ptp_set_timestamp_mode(struct ice_pf *pf, struct hwtstamp_config *config)
{
	/* Reserved for future extensions. */
	if (config->flags)
		return -EINVAL;

	switch (config->tx_type) {
	case HWTSTAMP_TX_OFF:
		ice_set_tx_tstamp(pf, false);
		break;
	case HWTSTAMP_TX_ON:
		ice_set_tx_tstamp(pf, true);
		break;
	default:
		return -ERANGE;
	}

	switch (config->rx_filter) {
	case HWTSTAMP_FILTER_NONE:
		ice_set_rx_tstamp(pf, false);
		break;
	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
	case HWTSTAMP_FILTER_NTP_ALL:
	case HWTSTAMP_FILTER_ALL:
		config->rx_filter = HWTSTAMP_FILTER_ALL;
		ice_set_rx_tstamp(pf, true);
		break;
	default:
		return -ERANGE;
	}

	return 0;
}

/**
 * ice_ptp_set_ts_config - ioctl interface to control the timestamping
 * @pf: Board private structure
 * @ifr: ioctl data
 *
 * Get the user config and store it
 */
int ice_ptp_set_ts_config(struct ice_pf *pf, struct ifreq *ifr)
{
	struct hwtstamp_config config;
	int err;

	if (!test_bit(ICE_FLAG_PTP, pf->flags))
		return -EAGAIN;

	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
		return -EFAULT;

	err = ice_ptp_set_timestamp_mode(pf, &config);
	if (err)
		return err;

	/* Save these settings for future reference */
	pf->ptp.tstamp_config = config;

	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
		-EFAULT : 0;
}

/**
 * ice_ptp_rx_hwtstamp - Check for an Rx timestamp
 * @rx_ring: Ring to get the VSI info
 * @rx_desc: Receive descriptor
 * @skb: Particular skb to send timestamp with
 *
 * The driver receives a notification in the receive descriptor with timestamp.
 * The timestamp is in ns, so we must convert the result first.
 */
void
ice_ptp_rx_hwtstamp(struct ice_ring *rx_ring,
		    union ice_32b_rx_flex_desc *rx_desc, struct sk_buff *skb)
{
	u32 ts_high;
	u64 ts_ns;

	/* Populate timesync data into skb */
	if (rx_desc->wb.time_stamp_low & ICE_PTP_TS_VALID) {
		struct skb_shared_hwtstamps *hwtstamps;

		/* Use ice_ptp_extend_32b_ts directly, using the ring-specific
		 * cached PHC value, rather than accessing the PF. This also
		 * allows us to simply pass the upper 32bits of nanoseconds
		 * directly. Calling ice_ptp_extend_40b_ts is unnecessary as
		 * it would just discard these bits itself.
		 */
		ts_high = le32_to_cpu(rx_desc->wb.flex_ts.ts_high);
		ts_ns = ice_ptp_extend_32b_ts(rx_ring->cached_phctime, ts_high);

		hwtstamps = skb_hwtstamps(skb);
		memset(hwtstamps, 0, sizeof(*hwtstamps));
		hwtstamps->hwtstamp = ns_to_ktime(ts_ns);
	}
}

/**
 * ice_ptp_setup_pins_e810 - Setup PTP pins in sysfs
 * @info: PTP clock capabilities
 */
static void ice_ptp_setup_pins_e810(struct ptp_clock_info *info)
{
	info->n_per_out = E810_N_PER_OUT;
	info->n_ext_ts = E810_N_EXT_TS;
}

/**
 * ice_ptp_set_funcs_e810 - Set specialized functions for E810 support
 * @pf: Board private structure
 * @info: PTP info to fill
 *
 * Assign functions to the PTP capabiltiies structure for E810 devices.
 * Functions which operate across all device families should be set directly
 * in ice_ptp_set_caps. Only add functions here which are distinct for e810
 * devices.
 */
static void
ice_ptp_set_funcs_e810(struct ice_pf *pf, struct ptp_clock_info *info)
{
	info->enable = ice_ptp_gpio_enable_e810;

	ice_ptp_setup_pins_e810(info);
}

/**
 * ice_ptp_set_caps - Set PTP capabilities
 * @pf: Board private structure
 */
static void ice_ptp_set_caps(struct ice_pf *pf)
{
	struct ptp_clock_info *info = &pf->ptp.info;
	struct device *dev = ice_pf_to_dev(pf);

	snprintf(info->name, sizeof(info->name) - 1, "%s-%s-clk",
		 dev_driver_string(dev), dev_name(dev));
	info->owner = THIS_MODULE;
	info->max_adj = 999999999;
	info->adjtime = ice_ptp_adjtime;
	info->adjfine = ice_ptp_adjfine;
	info->gettimex64 = ice_ptp_gettimex64;
	info->settime64 = ice_ptp_settime64;

	ice_ptp_set_funcs_e810(pf, info);
}

/**
 * ice_ptp_create_clock - Create PTP clock device for userspace
 * @pf: Board private structure
 *
 * This function creates a new PTP clock device. It only creates one if we
 * don't already have one. Will return error if it can't create one, but success
 * if we already have a device. Should be used by ice_ptp_init to create clock
 * initially, and prevent global resets from creating new clock devices.
 */
static long ice_ptp_create_clock(struct ice_pf *pf)
{
	struct ptp_clock_info *info;
	struct ptp_clock *clock;
	struct device *dev;

	/* No need to create a clock device if we already have one */
	if (pf->ptp.clock)
		return 0;

	ice_ptp_set_caps(pf);

	info = &pf->ptp.info;
	dev = ice_pf_to_dev(pf);

	/* Attempt to register the clock before enabling the hardware. */
	clock = ptp_clock_register(info, dev);
	if (IS_ERR(clock))
		return PTR_ERR(clock);

	pf->ptp.clock = clock;

	return 0;
}

/**
 * ice_ptp_tx_tstamp_work - Process Tx timestamps for a port
 * @work: pointer to the kthread_work struct
 *
 * Process timestamps captured by the PHY associated with this port. To do
 * this, loop over each index with a waiting skb.
 *
 * If a given index has a valid timestamp, perform the following steps:
 *
 * 1) copy the timestamp out of the PHY register
 * 4) clear the timestamp valid bit in the PHY register
 * 5) unlock the index by clearing the associated in_use bit.
 * 2) extend the 40b timestamp value to get a 64bit timestamp
 * 3) send that timestamp to the stack
 *
 * After looping, if we still have waiting SKBs, then re-queue the work. This
 * may cause us effectively poll even when not strictly necessary. We do this
 * because it's possible a new timestamp was requested around the same time as
 * the interrupt. In some cases hardware might not interrupt us again when the
 * timestamp is captured.
 *
 * Note that we only take the tracking lock when clearing the bit and when
 * checking if we need to re-queue this task. The only place where bits can be
 * set is the hard xmit routine where an SKB has a request flag set. The only
 * places where we clear bits are this work function, or the periodic cleanup
 * thread. If the cleanup thread clears a bit we're processing we catch it
 * when we lock to clear the bit and then grab the SKB pointer. If a Tx thread
 * starts a new timestamp, we might not begin processing it right away but we
 * will notice it at the end when we re-queue the work item. If a Tx thread
 * starts a new timestamp just after this function exits without re-queuing,
 * the interrupt when the timestamp finishes should trigger. Avoiding holding
 * the lock for the entire function is important in order to ensure that Tx
 * threads do not get blocked while waiting for the lock.
 */
static void ice_ptp_tx_tstamp_work(struct kthread_work *work)
{
	struct ice_ptp_port *ptp_port;
	struct ice_ptp_tx *tx;
	struct ice_pf *pf;
	struct ice_hw *hw;
	u8 idx;

	tx = container_of(work, struct ice_ptp_tx, work);
	if (!tx->init)
		return;

	ptp_port = container_of(tx, struct ice_ptp_port, tx);
	pf = ptp_port_to_pf(ptp_port);
	hw = &pf->hw;

	for_each_set_bit(idx, tx->in_use, tx->len) {
		struct skb_shared_hwtstamps shhwtstamps = {};
		u8 phy_idx = idx + tx->quad_offset;
		u64 raw_tstamp, tstamp;
		struct sk_buff *skb;
		int err;

		err = ice_read_phy_tstamp(hw, tx->quad, phy_idx,
					  &raw_tstamp);
		if (err)
			continue;

		/* Check if the timestamp is valid */
		if (!(raw_tstamp & ICE_PTP_TS_VALID))
			continue;

		/* clear the timestamp register, so that it won't show valid
		 * again when re-used.
		 */
		ice_clear_phy_tstamp(hw, tx->quad, phy_idx);

		/* The timestamp is valid, so we'll go ahead and clear this
		 * index and then send the timestamp up to the stack.
		 */
		spin_lock(&tx->lock);
		clear_bit(idx, tx->in_use);
		skb = tx->tstamps[idx].skb;
		tx->tstamps[idx].skb = NULL;
		spin_unlock(&tx->lock);

		/* it's (unlikely but) possible we raced with the cleanup
		 * thread for discarding old timestamp requests.
		 */
		if (!skb)
			continue;

		/* Extend the timestamp using cached PHC time */
		tstamp = ice_ptp_extend_40b_ts(pf, raw_tstamp);
		shhwtstamps.hwtstamp = ns_to_ktime(tstamp);

		skb_tstamp_tx(skb, &shhwtstamps);
		dev_kfree_skb_any(skb);
	}

	/* Check if we still have work to do. If so, re-queue this task to
	 * poll for remaining timestamps.
	 */
	spin_lock(&tx->lock);
	if (!bitmap_empty(tx->in_use, tx->len))
		kthread_queue_work(pf->ptp.kworker, &tx->work);
	spin_unlock(&tx->lock);
}

/**
 * ice_ptp_request_ts - Request an available Tx timestamp index
 * @tx: the PTP Tx timestamp tracker to request from
 * @skb: the SKB to associate with this timestamp request
 */
s8 ice_ptp_request_ts(struct ice_ptp_tx *tx, struct sk_buff *skb)
{
	u8 idx;

	/* Check if this tracker is initialized */
	if (!tx->init)
		return -1;

	spin_lock(&tx->lock);
	/* Find and set the first available index */
	idx = find_first_zero_bit(tx->in_use, tx->len);
	if (idx < tx->len) {
		/* We got a valid index that no other thread could have set. Store
		 * a reference to the skb and the start time to allow discarding old
		 * requests.
		 */
		set_bit(idx, tx->in_use);
		tx->tstamps[idx].start = jiffies;
		tx->tstamps[idx].skb = skb_get(skb);
		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
	}

	spin_unlock(&tx->lock);

	/* return the appropriate PHY timestamp register index, -1 if no
	 * indexes were available.
	 */
	if (idx >= tx->len)
		return -1;
	else
		return idx + tx->quad_offset;
}

/**
 * ice_ptp_process_ts - Spawn kthread work to handle timestamps
 * @pf: Board private structure
 *
 * Queue work required to process the PTP Tx timestamps outside of interrupt
 * context.
 */
void ice_ptp_process_ts(struct ice_pf *pf)
{
	if (pf->ptp.port.tx.init)
		kthread_queue_work(pf->ptp.kworker, &pf->ptp.port.tx.work);
}

/**
 * ice_ptp_alloc_tx_tracker - Initialize tracking for Tx timestamps
 * @tx: Tx tracking structure to initialize
 *
 * Assumes that the length has already been initialized. Do not call directly,
 * use the ice_ptp_init_tx_e822 or ice_ptp_init_tx_e810 instead.
 */
static int
ice_ptp_alloc_tx_tracker(struct ice_ptp_tx *tx)
{
	tx->tstamps = kcalloc(tx->len, sizeof(*tx->tstamps), GFP_KERNEL);
	if (!tx->tstamps)
		return -ENOMEM;

	tx->in_use = bitmap_zalloc(tx->len, GFP_KERNEL);
	if (!tx->in_use) {
		kfree(tx->tstamps);
		tx->tstamps = NULL;
		return -ENOMEM;
	}

	spin_lock_init(&tx->lock);
	kthread_init_work(&tx->work, ice_ptp_tx_tstamp_work);

	tx->init = 1;

	return 0;
}

/**
 * ice_ptp_flush_tx_tracker - Flush any remaining timestamps from the tracker
 * @pf: Board private structure
 * @tx: the tracker to flush
 */
static void
ice_ptp_flush_tx_tracker(struct ice_pf *pf, struct ice_ptp_tx *tx)
{
	u8 idx;

	spin_lock(&tx->lock);

	for (idx = 0; idx < tx->len; idx++) {
		u8 phy_idx = idx + tx->quad_offset;

		/* Clear any potential residual timestamp in the PHY block */
		if (!pf->hw.reset_ongoing)
			ice_clear_phy_tstamp(&pf->hw, tx->quad, phy_idx);

		if (tx->tstamps[idx].skb) {
			dev_kfree_skb_any(tx->tstamps[idx].skb);
			tx->tstamps[idx].skb = NULL;
		}
	}

	spin_unlock(&tx->lock);
}

/**
 * ice_ptp_release_tx_tracker - Release allocated memory for Tx tracker
 * @pf: Board private structure
 * @tx: Tx tracking structure to release
 *
 * Free memory associated with the Tx timestamp tracker.
 */
static void
ice_ptp_release_tx_tracker(struct ice_pf *pf, struct ice_ptp_tx *tx)
{
	tx->init = 0;

	kthread_cancel_work_sync(&tx->work);

	ice_ptp_flush_tx_tracker(pf, tx);

	kfree(tx->tstamps);
	tx->tstamps = NULL;

	kfree(tx->in_use);
	tx->in_use = NULL;

	tx->len = 0;
}

/**
 * ice_ptp_init_tx_e810 - Initialize tracking for Tx timestamps
 * @pf: Board private structure
 * @tx: the Tx tracking structure to initialize
 *
 * Initialize the Tx timestamp tracker for this PF. For E810 devices, each
 * port has its own block of timestamps, independent of the other ports.
 */
static int
ice_ptp_init_tx_e810(struct ice_pf *pf, struct ice_ptp_tx *tx)
{
	tx->quad = pf->hw.port_info->lport;
	tx->quad_offset = 0;
	tx->len = INDEX_PER_QUAD;

	return ice_ptp_alloc_tx_tracker(tx);
}

/**
 * ice_ptp_tx_tstamp_cleanup - Cleanup old timestamp requests that got dropped
 * @tx: PTP Tx tracker to clean up
 *
 * Loop through the Tx timestamp requests and see if any of them have been
 * waiting for a long time. Discard any SKBs that have been waiting for more
 * than 2 seconds. This is long enough to be reasonably sure that the
 * timestamp will never be captured. This might happen if the packet gets
 * discarded before it reaches the PHY timestamping block.
 */
static void ice_ptp_tx_tstamp_cleanup(struct ice_ptp_tx *tx)
{
	u8 idx;

	if (!tx->init)
		return;

	for_each_set_bit(idx, tx->in_use, tx->len) {
		struct sk_buff *skb;

		/* Check if this SKB has been waiting for too long */
		if (time_is_after_jiffies(tx->tstamps[idx].start + 2 * HZ))
			continue;

		spin_lock(&tx->lock);
		skb = tx->tstamps[idx].skb;
		tx->tstamps[idx].skb = NULL;
		clear_bit(idx, tx->in_use);
		spin_unlock(&tx->lock);

		/* Free the SKB after we've cleared the bit */
		dev_kfree_skb_any(skb);
	}
}

static void ice_ptp_periodic_work(struct kthread_work *work)
{
	struct ice_ptp *ptp = container_of(work, struct ice_ptp, work.work);
	struct ice_pf *pf = container_of(ptp, struct ice_pf, ptp);

	if (!test_bit(ICE_FLAG_PTP, pf->flags))
		return;

	ice_ptp_update_cached_phctime(pf);

	ice_ptp_tx_tstamp_cleanup(&pf->ptp.port.tx);

	/* Run twice a second */
	kthread_queue_delayed_work(ptp->kworker, &ptp->work,
				   msecs_to_jiffies(500));
}

/**
 * ice_ptp_init_owner - Initialize PTP_1588_CLOCK device
 * @pf: Board private structure
 *
 * Setup and initialize a PTP clock device that represents the device hardware
 * clock. Save the clock index for other functions connected to the same
 * hardware resource.
 */
static int ice_ptp_init_owner(struct ice_pf *pf)
{
	struct device *dev = ice_pf_to_dev(pf);
	struct ice_hw *hw = &pf->hw;
	struct timespec64 ts;
	u8 src_idx;
	int err;

	wr32(hw, GLTSYN_SYNC_DLAY, 0);

	/* Clear some HW residue and enable source clock */
	src_idx = hw->func_caps.ts_func_info.tmr_index_owned;

	/* Enable source clocks */
	wr32(hw, GLTSYN_ENA(src_idx), GLTSYN_ENA_TSYN_ENA_M);

	/* Enable PHY time sync */
	err = ice_ptp_init_phy_e810(hw);
	if (err)
		goto err_exit;

	/* Clear event status indications for auxiliary pins */
	(void)rd32(hw, GLTSYN_STAT(src_idx));

	/* Acquire the global hardware lock */
	if (!ice_ptp_lock(hw)) {
		err = -EBUSY;
		goto err_exit;
	}

	/* Write the increment time value to PHY and LAN */
	err = ice_ptp_write_incval(hw, ICE_PTP_NOMINAL_INCVAL_E810);
	if (err) {
		ice_ptp_unlock(hw);
		goto err_exit;
	}

	ts = ktime_to_timespec64(ktime_get_real());
	/* Write the initial Time value to PHY and LAN */
	err = ice_ptp_write_init(pf, &ts);
	if (err) {
		ice_ptp_unlock(hw);
		goto err_exit;
	}

	/* Release the global hardware lock */
	ice_ptp_unlock(hw);

	/* Ensure we have a clock device */
	err = ice_ptp_create_clock(pf);
	if (err)
		goto err_clk;

	/* Store the PTP clock index for other PFs */
	ice_set_ptp_clock_index(pf);

	return 0;

err_clk:
	pf->ptp.clock = NULL;
err_exit:
	dev_err(dev, "PTP failed to register clock, err %d\n", err);

	return err;
}

/**
 * ice_ptp_init - Initialize the PTP support after device probe or reset
 * @pf: Board private structure
 *
 * This function sets device up for PTP support. The first time it is run, it
 * will create a clock device. It does not create a clock device if one
 * already exists. It also reconfigures the device after a reset.
 */
void ice_ptp_init(struct ice_pf *pf)
{
	struct device *dev = ice_pf_to_dev(pf);
	struct kthread_worker *kworker;
	struct ice_hw *hw = &pf->hw;
	int err;

	/* PTP is currently only supported on E810 devices */
	if (!ice_is_e810(hw))
		return;

	/* Check if this PF owns the source timer */
	if (hw->func_caps.ts_func_info.src_tmr_owned) {
		err = ice_ptp_init_owner(pf);
		if (err)
			return;
	}

	/* Disable timestamping for both Tx and Rx */
	ice_ptp_cfg_timestamp(pf, false);

	/* Initialize the PTP port Tx timestamp tracker */
	ice_ptp_init_tx_e810(pf, &pf->ptp.port.tx);

	/* Initialize work functions */
	kthread_init_delayed_work(&pf->ptp.work, ice_ptp_periodic_work);
	kthread_init_work(&pf->ptp.extts_work, ice_ptp_extts_work);

	/* Allocate a kworker for handling work required for the ports
	 * connected to the PTP hardware clock.
	 */
	kworker = kthread_create_worker(0, "ice-ptp-%s", dev_name(dev));
	if (IS_ERR(kworker)) {
		err = PTR_ERR(kworker);
		goto err_kworker;
	}
	pf->ptp.kworker = kworker;

	set_bit(ICE_FLAG_PTP, pf->flags);

	/* Start periodic work going */
	kthread_queue_delayed_work(pf->ptp.kworker, &pf->ptp.work, 0);

	dev_info(dev, "PTP init successful\n");
	return;

err_kworker:
	/* If we registered a PTP clock, release it */
	if (pf->ptp.clock) {
		ptp_clock_unregister(pf->ptp.clock);
		pf->ptp.clock = NULL;
	}
	dev_err(dev, "PTP failed %d\n", err);
}

/**
 * ice_ptp_release - Disable the driver/HW support and unregister the clock
 * @pf: Board private structure
 *
 * This function handles the cleanup work required from the initialization by
 * clearing out the important information and unregistering the clock
 */
void ice_ptp_release(struct ice_pf *pf)
{
	/* Disable timestamping for both Tx and Rx */
	ice_ptp_cfg_timestamp(pf, false);

	ice_ptp_release_tx_tracker(pf, &pf->ptp.port.tx);

	clear_bit(ICE_FLAG_PTP, pf->flags);

	kthread_cancel_delayed_work_sync(&pf->ptp.work);

	if (pf->ptp.kworker) {
		kthread_destroy_worker(pf->ptp.kworker);
		pf->ptp.kworker = NULL;
	}

	if (!pf->ptp.clock)
		return;

	/* Disable periodic outputs */
	ice_ptp_disable_all_clkout(pf);

	ice_clear_ptp_clock_index(pf);
	ptp_clock_unregister(pf->ptp.clock);
	pf->ptp.clock = NULL;

	dev_info(ice_pf_to_dev(pf), "Removed PTP clock\n");
}