summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/intel/ixgbe/ixgbe_ptp.c
blob: 5184e2a1a7d8249bc746ce6496e55f5789a0e949 (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
/*******************************************************************************

  Intel 10 Gigabit PCI Express Linux driver
  Copyright(c) 1999 - 2013 Intel Corporation.

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  more details.

  You should have received a copy of the GNU General Public License along with
  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information:
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

*******************************************************************************/
#include "ixgbe.h"
#include <linux/export.h>
#include <linux/ptp_classify.h>

/*
 * The 82599 and the X540 do not have true 64bit nanosecond scale
 * counter registers. Instead, SYSTIME is defined by a fixed point
 * system which allows the user to define the scale counter increment
 * value at every level change of the oscillator driving the SYSTIME
 * value. For both devices the TIMINCA:IV field defines this
 * increment. On the X540 device, 31 bits are provided. However on the
 * 82599 only provides 24 bits. The time unit is determined by the
 * clock frequency of the oscillator in combination with the TIMINCA
 * register. When these devices link at 10Gb the oscillator has a
 * period of 6.4ns. In order to convert the scale counter into
 * nanoseconds the cyclecounter and timecounter structures are
 * used. The SYSTIME registers need to be converted to ns values by use
 * of only a right shift (division by power of 2). The following math
 * determines the largest incvalue that will fit into the available
 * bits in the TIMINCA register.
 *
 * PeriodWidth: Number of bits to store the clock period
 * MaxWidth: The maximum width value of the TIMINCA register
 * Period: The clock period for the oscillator
 * round(): discard the fractional portion of the calculation
 *
 * Period * [ 2 ^ ( MaxWidth - PeriodWidth ) ]
 *
 * For the X540, MaxWidth is 31 bits, and the base period is 6.4 ns
 * For the 82599, MaxWidth is 24 bits, and the base period is 6.4 ns
 *
 * The period also changes based on the link speed:
 * At 10Gb link or no link, the period remains the same.
 * At 1Gb link, the period is multiplied by 10. (64ns)
 * At 100Mb link, the period is multiplied by 100. (640ns)
 *
 * The calculated value allows us to right shift the SYSTIME register
 * value in order to quickly convert it into a nanosecond clock,
 * while allowing for the maximum possible adjustment value.
 *
 * These diagrams are only for the 10Gb link period
 *
 *           SYSTIMEH            SYSTIMEL
 *       +--------------+  +--------------+
 * X540  |      32      |  | 1 | 3 |  28  |
 *       *--------------+  +--------------+
 *        \________ 36 bits ______/  fract
 *
 *       +--------------+  +--------------+
 * 82599 |      32      |  | 8 | 3 |  21  |
 *       *--------------+  +--------------+
 *        \________ 43 bits ______/  fract
 *
 * The 36 bit X540 SYSTIME overflows every
 *   2^36 * 10^-9 / 60 = 1.14 minutes or 69 seconds
 *
 * The 43 bit 82599 SYSTIME overflows every
 *   2^43 * 10^-9 / 3600 = 2.4 hours
 */
#define IXGBE_INCVAL_10GB 0x66666666
#define IXGBE_INCVAL_1GB  0x40000000
#define IXGBE_INCVAL_100  0x50000000

#define IXGBE_INCVAL_SHIFT_10GB  28
#define IXGBE_INCVAL_SHIFT_1GB   24
#define IXGBE_INCVAL_SHIFT_100   21

#define IXGBE_INCVAL_SHIFT_82599 7
#define IXGBE_INCPER_SHIFT_82599 24
#define IXGBE_MAX_TIMEADJ_VALUE  0x7FFFFFFFFFFFFFFFULL

#define IXGBE_OVERFLOW_PERIOD    (HZ * 30)
#define IXGBE_PTP_TX_TIMEOUT     (HZ * 15)

#ifndef NSECS_PER_SEC
#define NSECS_PER_SEC 1000000000ULL
#endif

/**
 * ixgbe_ptp_setup_sdp
 * @hw: the hardware private structure
 *
 * this function enables or disables the clock out feature on SDP0 for
 * the X540 device. It will create a 1second periodic output that can
 * be used as the PPS (via an interrupt).
 *
 * It calculates when the systime will be on an exact second, and then
 * aligns the start of the PPS signal to that value. The shift is
 * necessary because it can change based on the link speed.
 */
static void ixgbe_ptp_setup_sdp(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	int shift = adapter->cc.shift;
	u32 esdp, tsauxc, clktiml, clktimh, trgttiml, trgttimh, rem;
	u64 ns = 0, clock_edge = 0;

	if ((adapter->flags2 & IXGBE_FLAG2_PTP_PPS_ENABLED) &&
	    (hw->mac.type == ixgbe_mac_X540)) {

		/* disable the pin first */
		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
		IXGBE_WRITE_FLUSH(hw);

		esdp = IXGBE_READ_REG(hw, IXGBE_ESDP);

		/*
		 * enable the SDP0 pin as output, and connected to the
		 * native function for Timesync (ClockOut)
		 */
		esdp |= (IXGBE_ESDP_SDP0_DIR |
			 IXGBE_ESDP_SDP0_NATIVE);

		/*
		 * enable the Clock Out feature on SDP0, and allow
		 * interrupts to occur when the pin changes
		 */
		tsauxc = (IXGBE_TSAUXC_EN_CLK |
			  IXGBE_TSAUXC_SYNCLK |
			  IXGBE_TSAUXC_SDP0_INT);

		/* clock period (or pulse length) */
		clktiml = (u32)(NSECS_PER_SEC << shift);
		clktimh = (u32)((NSECS_PER_SEC << shift) >> 32);

		/*
		 * Account for the cyclecounter wrap-around value by
		 * using the converted ns value of the current time to
		 * check for when the next aligned second would occur.
		 */
		clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
		clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
		ns = timecounter_cyc2time(&adapter->tc, clock_edge);

		div_u64_rem(ns, NSECS_PER_SEC, &rem);
		clock_edge += ((NSECS_PER_SEC - (u64)rem) << shift);

		/* specify the initial clock start time */
		trgttiml = (u32)clock_edge;
		trgttimh = (u32)(clock_edge >> 32);

		IXGBE_WRITE_REG(hw, IXGBE_CLKTIML, clktiml);
		IXGBE_WRITE_REG(hw, IXGBE_CLKTIMH, clktimh);
		IXGBE_WRITE_REG(hw, IXGBE_TRGTTIML0, trgttiml);
		IXGBE_WRITE_REG(hw, IXGBE_TRGTTIMH0, trgttimh);

		IXGBE_WRITE_REG(hw, IXGBE_ESDP, esdp);
		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, tsauxc);
	} else {
		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
	}

	IXGBE_WRITE_FLUSH(hw);
}

/**
 * ixgbe_ptp_read - read raw cycle counter (to be used by time counter)
 * @cc: the cyclecounter structure
 *
 * this function reads the cyclecounter registers and is called by the
 * cyclecounter structure used to construct a ns counter from the
 * arbitrary fixed point registers
 */
static cycle_t ixgbe_ptp_read(const struct cyclecounter *cc)
{
	struct ixgbe_adapter *adapter =
		container_of(cc, struct ixgbe_adapter, cc);
	struct ixgbe_hw *hw = &adapter->hw;
	u64 stamp = 0;

	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;

	return stamp;
}

/**
 * ixgbe_ptp_adjfreq
 * @ptp: the ptp clock structure
 * @ppb: parts per billion adjustment from base
 *
 * adjust the frequency of the ptp cycle counter by the
 * indicated ppb from the base frequency.
 */
static int ixgbe_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
{
	struct ixgbe_adapter *adapter =
		container_of(ptp, struct ixgbe_adapter, ptp_caps);
	struct ixgbe_hw *hw = &adapter->hw;
	u64 freq;
	u32 diff, incval;
	int neg_adj = 0;

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

	smp_mb();
	incval = ACCESS_ONCE(adapter->base_incval);

	freq = incval;
	freq *= ppb;
	diff = div_u64(freq, 1000000000ULL);

	incval = neg_adj ? (incval - diff) : (incval + diff);

	switch (hw->mac.type) {
	case ixgbe_mac_X540:
		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
		break;
	case ixgbe_mac_82599EB:
		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
				(1 << IXGBE_INCPER_SHIFT_82599) |
				incval);
		break;
	default:
		break;
	}

	return 0;
}

/**
 * ixgbe_ptp_adjtime
 * @ptp: the ptp clock structure
 * @delta: offset to adjust the cycle counter by
 *
 * adjust the timer by resetting the timecounter structure.
 */
static int ixgbe_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
	struct ixgbe_adapter *adapter =
		container_of(ptp, struct ixgbe_adapter, ptp_caps);
	unsigned long flags;
	u64 now;

	spin_lock_irqsave(&adapter->tmreg_lock, flags);

	now = timecounter_read(&adapter->tc);
	now += delta;

	/* reset the timecounter */
	timecounter_init(&adapter->tc,
			 &adapter->cc,
			 now);

	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	ixgbe_ptp_setup_sdp(adapter);

	return 0;
}

/**
 * ixgbe_ptp_gettime
 * @ptp: the ptp clock structure
 * @ts: timespec structure to hold the current time value
 *
 * read the timecounter and return the correct value on ns,
 * after converting it into a struct timespec.
 */
static int ixgbe_ptp_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
{
	struct ixgbe_adapter *adapter =
		container_of(ptp, struct ixgbe_adapter, ptp_caps);
	u64 ns;
	u32 remainder;
	unsigned long flags;

	spin_lock_irqsave(&adapter->tmreg_lock, flags);
	ns = timecounter_read(&adapter->tc);
	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	ts->tv_sec = div_u64_rem(ns, 1000000000ULL, &remainder);
	ts->tv_nsec = remainder;

	return 0;
}

/**
 * ixgbe_ptp_settime
 * @ptp: the ptp clock structure
 * @ts: the timespec containing the new time for the cycle counter
 *
 * reset the timecounter to use a new base value instead of the kernel
 * wall timer value.
 */
static int ixgbe_ptp_settime(struct ptp_clock_info *ptp,
			     const struct timespec *ts)
{
	struct ixgbe_adapter *adapter =
		container_of(ptp, struct ixgbe_adapter, ptp_caps);
	u64 ns;
	unsigned long flags;

	ns = ts->tv_sec * 1000000000ULL;
	ns += ts->tv_nsec;

	/* reset the timecounter */
	spin_lock_irqsave(&adapter->tmreg_lock, flags);
	timecounter_init(&adapter->tc, &adapter->cc, ns);
	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	ixgbe_ptp_setup_sdp(adapter);
	return 0;
}

/**
 * ixgbe_ptp_enable
 * @ptp: the ptp clock structure
 * @rq: the requested feature to change
 * @on: whether to enable or disable the feature
 *
 * enable (or disable) ancillary features of the phc subsystem.
 * our driver only supports the PPS feature on the X540
 */
static int ixgbe_ptp_enable(struct ptp_clock_info *ptp,
			    struct ptp_clock_request *rq, int on)
{
	struct ixgbe_adapter *adapter =
		container_of(ptp, struct ixgbe_adapter, ptp_caps);

	/**
	 * When PPS is enabled, unmask the interrupt for the ClockOut
	 * feature, so that the interrupt handler can send the PPS
	 * event when the clock SDP triggers. Clear mask when PPS is
	 * disabled
	 */
	if (rq->type == PTP_CLK_REQ_PPS) {
		switch (adapter->hw.mac.type) {
		case ixgbe_mac_X540:
			if (on)
				adapter->flags2 |= IXGBE_FLAG2_PTP_PPS_ENABLED;
			else
				adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;

			ixgbe_ptp_setup_sdp(adapter);
			return 0;
		default:
			break;
		}
	}

	return -ENOTSUPP;
}

/**
 * ixgbe_ptp_check_pps_event
 * @adapter: the private adapter structure
 * @eicr: the interrupt cause register value
 *
 * This function is called by the interrupt routine when checking for
 * interrupts. It will check and handle a pps event.
 */
void ixgbe_ptp_check_pps_event(struct ixgbe_adapter *adapter, u32 eicr)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct ptp_clock_event event;

	event.type = PTP_CLOCK_PPS;

	/* this check is necessary in case the interrupt was enabled via some
	 * alternative means (ex. debug_fs). Better to check here than
	 * everywhere that calls this function.
	 */
	if (!adapter->ptp_clock)
		return;

	switch (hw->mac.type) {
	case ixgbe_mac_X540:
		ptp_clock_event(adapter->ptp_clock, &event);
		break;
	default:
		break;
	}
}

/**
 * ixgbe_ptp_overflow_check - watchdog task to detect SYSTIME overflow
 * @adapter: private adapter struct
 *
 * this watchdog task periodically reads the timecounter
 * in order to prevent missing when the system time registers wrap
 * around. This needs to be run approximately twice a minute.
 */
void ixgbe_ptp_overflow_check(struct ixgbe_adapter *adapter)
{
	bool timeout = time_is_before_jiffies(adapter->last_overflow_check +
					     IXGBE_OVERFLOW_PERIOD);
	struct timespec ts;

	if (timeout) {
		ixgbe_ptp_gettime(&adapter->ptp_caps, &ts);
		adapter->last_overflow_check = jiffies;
	}
}

/**
 * ixgbe_ptp_rx_hang - detect error case when Rx timestamp registers latched
 * @adapter: private network adapter structure
 *
 * this watchdog task is scheduled to detect error case where hardware has
 * dropped an Rx packet that was timestamped when the ring is full. The
 * particular error is rare but leaves the device in a state unable to timestamp
 * any future packets.
 */
void ixgbe_ptp_rx_hang(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct ixgbe_ring *rx_ring;
	u32 tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
	unsigned long rx_event;
	int n;

	/* if we don't have a valid timestamp in the registers, just update the
	 * timeout counter and exit
	 */
	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID)) {
		adapter->last_rx_ptp_check = jiffies;
		return;
	}

	/* determine the most recent watchdog or rx_timestamp event */
	rx_event = adapter->last_rx_ptp_check;
	for (n = 0; n < adapter->num_rx_queues; n++) {
		rx_ring = adapter->rx_ring[n];
		if (time_after(rx_ring->last_rx_timestamp, rx_event))
			rx_event = rx_ring->last_rx_timestamp;
	}

	/* only need to read the high RXSTMP register to clear the lock */
	if (time_is_before_jiffies(rx_event + 5*HZ)) {
		IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
		adapter->last_rx_ptp_check = jiffies;

		e_warn(drv, "clearing RX Timestamp hang");
	}
}

/**
 * ixgbe_ptp_tx_hwtstamp - utility function which checks for TX time stamp
 * @adapter: the private adapter struct
 *
 * if the timestamp is valid, we convert it into the timecounter ns
 * value, then store that result into the shhwtstamps structure which
 * is passed up the network stack
 */
static void ixgbe_ptp_tx_hwtstamp(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct skb_shared_hwtstamps shhwtstamps;
	u64 regval = 0, ns;
	unsigned long flags;

	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPL);
	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPH) << 32;

	spin_lock_irqsave(&adapter->tmreg_lock, flags);
	ns = timecounter_cyc2time(&adapter->tc, regval);
	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	memset(&shhwtstamps, 0, sizeof(shhwtstamps));
	shhwtstamps.hwtstamp = ns_to_ktime(ns);
	skb_tstamp_tx(adapter->ptp_tx_skb, &shhwtstamps);

	dev_kfree_skb_any(adapter->ptp_tx_skb);
	adapter->ptp_tx_skb = NULL;
}

/**
 * ixgbe_ptp_tx_hwtstamp_work
 * @work: pointer to the work struct
 *
 * This work item polls TSYNCTXCTL valid bit to determine when a Tx hardware
 * timestamp has been taken for the current skb. It is necesary, because the
 * descriptor's "done" bit does not correlate with the timestamp event.
 */
static void ixgbe_ptp_tx_hwtstamp_work(struct work_struct *work)
{
	struct ixgbe_adapter *adapter = container_of(work, struct ixgbe_adapter,
						     ptp_tx_work);
	struct ixgbe_hw *hw = &adapter->hw;
	bool timeout = time_is_before_jiffies(adapter->ptp_tx_start +
					      IXGBE_PTP_TX_TIMEOUT);
	u32 tsynctxctl;

	/* we have to have a valid skb */
	if (!adapter->ptp_tx_skb)
		return;

	if (timeout) {
		dev_kfree_skb_any(adapter->ptp_tx_skb);
		adapter->ptp_tx_skb = NULL;
		e_warn(drv, "clearing Tx Timestamp hang");
		return;
	}

	tsynctxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
	if (tsynctxctl & IXGBE_TSYNCTXCTL_VALID)
		ixgbe_ptp_tx_hwtstamp(adapter);
	else
		/* reschedule to keep checking if it's not available yet */
		schedule_work(&adapter->ptp_tx_work);
}

/**
 * __ixgbe_ptp_rx_hwtstamp - utility function which checks for RX time stamp
 * @q_vector: structure containing interrupt and ring information
 * @skb: particular skb to send timestamp with
 *
 * if the timestamp is valid, we convert it into the timecounter ns
 * value, then store that result into the shhwtstamps structure which
 * is passed up the network stack
 */
void __ixgbe_ptp_rx_hwtstamp(struct ixgbe_q_vector *q_vector,
			     struct sk_buff *skb)
{
	struct ixgbe_adapter *adapter;
	struct ixgbe_hw *hw;
	struct skb_shared_hwtstamps *shhwtstamps;
	u64 regval = 0, ns;
	u32 tsyncrxctl;
	unsigned long flags;

	/* we cannot process timestamps on a ring without a q_vector */
	if (!q_vector || !q_vector->adapter)
		return;

	adapter = q_vector->adapter;
	hw = &adapter->hw;

	/*
	 * Read the tsyncrxctl register afterwards in order to prevent taking an
	 * I/O hit on every packet.
	 */
	tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID))
		return;

	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPL);
	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPH) << 32;


	spin_lock_irqsave(&adapter->tmreg_lock, flags);
	ns = timecounter_cyc2time(&adapter->tc, regval);
	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	shhwtstamps = skb_hwtstamps(skb);
	shhwtstamps->hwtstamp = ns_to_ktime(ns);
}

/**
 * ixgbe_ptp_hwtstamp_ioctl - control hardware time stamping
 * @adapter: pointer to adapter struct
 * @ifreq: ioctl data
 * @cmd: particular ioctl requested
 *
 * Outgoing time stamping can be enabled and disabled. Play nice and
 * disable it when requested, although it shouldn't case any overhead
 * when no packet needs it. At most one packet in the queue may be
 * marked for time stamping, otherwise it would be impossible to tell
 * for sure to which packet the hardware time stamp belongs.
 *
 * Incoming time stamping has to be configured via the hardware
 * filters. Not all combinations are supported, in particular event
 * type has to be specified. Matching the kind of event packet is
 * not supported, with the exception of "all V2 events regardless of
 * level 2 or 4".
 *
 * Since hardware always timestamps Path delay packets when timestamping V2
 * packets, regardless of the type specified in the register, only use V2
 * Event mode. This more accurately tells the user what the hardware is going
 * to do anyways.
 */
int ixgbe_ptp_hwtstamp_ioctl(struct ixgbe_adapter *adapter,
			     struct ifreq *ifr, int cmd)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct hwtstamp_config config;
	u32 tsync_tx_ctl = IXGBE_TSYNCTXCTL_ENABLED;
	u32 tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED;
	u32 tsync_rx_mtrl = PTP_EV_PORT << 16;
	bool is_l2 = false;
	u32 regval;

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

	/* reserved for future extensions */
	if (config.flags)
		return -EINVAL;

	switch (config.tx_type) {
	case HWTSTAMP_TX_OFF:
		tsync_tx_ctl = 0;
	case HWTSTAMP_TX_ON:
		break;
	default:
		return -ERANGE;
	}

	switch (config.rx_filter) {
	case HWTSTAMP_FILTER_NONE:
		tsync_rx_ctl = 0;
		tsync_rx_mtrl = 0;
		break;
	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_SYNC_MSG;
		break;
	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_DELAY_REQ_MSG;
		break;
	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:
		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_EVENT_V2;
		is_l2 = true;
		config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
		break;
	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
	case HWTSTAMP_FILTER_ALL:
	default:
		/*
		 * register RXMTRL must be set in order to do V1 packets,
		 * therefore it is not possible to time stamp both V1 Sync and
		 * Delay_Req messages and hardware does not support
		 * timestamping all packets => return error
		 */
		config.rx_filter = HWTSTAMP_FILTER_NONE;
		return -ERANGE;
	}

	if (hw->mac.type == ixgbe_mac_82598EB) {
		if (tsync_rx_ctl | tsync_tx_ctl)
			return -ERANGE;
		return 0;
	}

	/* define ethertype filter for timestamping L2 packets */
	if (is_l2)
		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
				(IXGBE_ETQF_FILTER_EN | /* enable filter */
				 IXGBE_ETQF_1588 | /* enable timestamping */
				 ETH_P_1588));     /* 1588 eth protocol type */
	else
		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588), 0);


	/* enable/disable TX */
	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
	regval &= ~IXGBE_TSYNCTXCTL_ENABLED;
	regval |= tsync_tx_ctl;
	IXGBE_WRITE_REG(hw, IXGBE_TSYNCTXCTL, regval);

	/* enable/disable RX */
	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
	regval &= ~(IXGBE_TSYNCRXCTL_ENABLED | IXGBE_TSYNCRXCTL_TYPE_MASK);
	regval |= tsync_rx_ctl;
	IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, regval);

	/* define which PTP packets are time stamped */
	IXGBE_WRITE_REG(hw, IXGBE_RXMTRL, tsync_rx_mtrl);

	IXGBE_WRITE_FLUSH(hw);

	/* clear TX/RX time stamp registers, just to be sure */
	regval = IXGBE_READ_REG(hw, IXGBE_TXSTMPH);
	regval = IXGBE_READ_REG(hw, IXGBE_RXSTMPH);

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

/**
 * ixgbe_ptp_start_cyclecounter - create the cycle counter from hw
 * @adapter: pointer to the adapter structure
 *
 * This function should be called to set the proper values for the TIMINCA
 * register and tell the cyclecounter structure what the tick rate of SYSTIME
 * is. It does not directly modify SYSTIME registers or the timecounter
 * structure. It should be called whenever a new TIMINCA value is necessary,
 * such as during initialization or when the link speed changes.
 */
void ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	u32 incval = 0;
	u32 shift = 0;
	unsigned long flags;

	/**
	 * Scale the NIC cycle counter by a large factor so that
	 * relatively small corrections to the frequency can be added
	 * or subtracted. The drawbacks of a large factor include
	 * (a) the clock register overflows more quickly, (b) the cycle
	 * counter structure must be able to convert the systime value
	 * to nanoseconds using only a multiplier and a right-shift,
	 * and (c) the value must fit within the timinca register space
	 * => math based on internal DMA clock rate and available bits
	 *
	 * Note that when there is no link, internal DMA clock is same as when
	 * link speed is 10Gb. Set the registers correctly even when link is
	 * down to preserve the clock setting
	 */
	switch (adapter->link_speed) {
	case IXGBE_LINK_SPEED_100_FULL:
		incval = IXGBE_INCVAL_100;
		shift = IXGBE_INCVAL_SHIFT_100;
		break;
	case IXGBE_LINK_SPEED_1GB_FULL:
		incval = IXGBE_INCVAL_1GB;
		shift = IXGBE_INCVAL_SHIFT_1GB;
		break;
	case IXGBE_LINK_SPEED_10GB_FULL:
	default:
		incval = IXGBE_INCVAL_10GB;
		shift = IXGBE_INCVAL_SHIFT_10GB;
		break;
	}

	/**
	 * Modify the calculated values to fit within the correct
	 * number of bits specified by the hardware. The 82599 doesn't
	 * have the same space as the X540, so bitshift the calculated
	 * values to fit.
	 */
	switch (hw->mac.type) {
	case ixgbe_mac_X540:
		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
		break;
	case ixgbe_mac_82599EB:
		incval >>= IXGBE_INCVAL_SHIFT_82599;
		shift -= IXGBE_INCVAL_SHIFT_82599;
		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
				(1 << IXGBE_INCPER_SHIFT_82599) |
				incval);
		break;
	default:
		/* other devices aren't supported */
		return;
	}

	/* update the base incval used to calculate frequency adjustment */
	ACCESS_ONCE(adapter->base_incval) = incval;
	smp_mb();

	/* need lock to prevent incorrect read while modifying cyclecounter */
	spin_lock_irqsave(&adapter->tmreg_lock, flags);

	memset(&adapter->cc, 0, sizeof(adapter->cc));
	adapter->cc.read = ixgbe_ptp_read;
	adapter->cc.mask = CLOCKSOURCE_MASK(64);
	adapter->cc.shift = shift;
	adapter->cc.mult = 1;

	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
}

/**
 * ixgbe_ptp_reset
 * @adapter: the ixgbe private board structure
 *
 * When the MAC resets, all timesync features are reset. This function should be
 * called to re-enable the PTP clock structure. It will re-init the timecounter
 * structure based on the kernel time as well as setup the cycle counter data.
 */
void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	unsigned long flags;

	/* set SYSTIME registers to 0 just in case */
	IXGBE_WRITE_REG(hw, IXGBE_SYSTIML, 0x00000000);
	IXGBE_WRITE_REG(hw, IXGBE_SYSTIMH, 0x00000000);
	IXGBE_WRITE_FLUSH(hw);

	ixgbe_ptp_start_cyclecounter(adapter);

	spin_lock_irqsave(&adapter->tmreg_lock, flags);

	/* reset the ns time counter */
	timecounter_init(&adapter->tc, &adapter->cc,
			 ktime_to_ns(ktime_get_real()));

	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);

	/*
	 * Now that the shift has been calculated and the systime
	 * registers reset, (re-)enable the Clock out feature
	 */
	ixgbe_ptp_setup_sdp(adapter);
}

/**
 * ixgbe_ptp_init
 * @adapter: the ixgbe private adapter structure
 *
 * This function performs the required steps for enabling ptp
 * support. If ptp support has already been loaded it simply calls the
 * cyclecounter init routine and exits.
 */
void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;

	switch (adapter->hw.mac.type) {
	case ixgbe_mac_X540:
		snprintf(adapter->ptp_caps.name, 16, "%s", netdev->name);
		adapter->ptp_caps.owner = THIS_MODULE;
		adapter->ptp_caps.max_adj = 250000000;
		adapter->ptp_caps.n_alarm = 0;
		adapter->ptp_caps.n_ext_ts = 0;
		adapter->ptp_caps.n_per_out = 0;
		adapter->ptp_caps.pps = 1;
		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq;
		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
		adapter->ptp_caps.gettime = ixgbe_ptp_gettime;
		adapter->ptp_caps.settime = ixgbe_ptp_settime;
		adapter->ptp_caps.enable = ixgbe_ptp_enable;
		break;
	case ixgbe_mac_82599EB:
		snprintf(adapter->ptp_caps.name, 16, "%s", netdev->name);
		adapter->ptp_caps.owner = THIS_MODULE;
		adapter->ptp_caps.max_adj = 250000000;
		adapter->ptp_caps.n_alarm = 0;
		adapter->ptp_caps.n_ext_ts = 0;
		adapter->ptp_caps.n_per_out = 0;
		adapter->ptp_caps.pps = 0;
		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq;
		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
		adapter->ptp_caps.gettime = ixgbe_ptp_gettime;
		adapter->ptp_caps.settime = ixgbe_ptp_settime;
		adapter->ptp_caps.enable = ixgbe_ptp_enable;
		break;
	default:
		adapter->ptp_clock = NULL;
		return;
	}

	spin_lock_init(&adapter->tmreg_lock);
	INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);

	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
						&adapter->pdev->dev);
	if (IS_ERR(adapter->ptp_clock)) {
		adapter->ptp_clock = NULL;
		e_dev_err("ptp_clock_register failed\n");
	} else
		e_dev_info("registered PHC device on %s\n", netdev->name);

	ixgbe_ptp_reset(adapter);

	/* enter the IXGBE_PTP_RUNNING state */
	set_bit(__IXGBE_PTP_RUNNING, &adapter->state);

	return;
}

/**
 * ixgbe_ptp_stop - disable ptp device and stop the overflow check
 * @adapter: pointer to adapter struct
 *
 * this function stops the ptp support, and cancels the delayed work.
 */
void ixgbe_ptp_stop(struct ixgbe_adapter *adapter)
{
	/* Leave the IXGBE_PTP_RUNNING state. */
	if (!test_and_clear_bit(__IXGBE_PTP_RUNNING, &adapter->state))
		return;

	/* stop the PPS signal */
	adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
	ixgbe_ptp_setup_sdp(adapter);

	cancel_work_sync(&adapter->ptp_tx_work);
	if (adapter->ptp_tx_skb) {
		dev_kfree_skb_any(adapter->ptp_tx_skb);
		adapter->ptp_tx_skb = NULL;
	}

	if (adapter->ptp_clock) {
		ptp_clock_unregister(adapter->ptp_clock);
		adapter->ptp_clock = NULL;
		e_dev_info("removed PHC on %s\n",
			   adapter->netdev->name);
	}
}
OpenPOWER on IntegriCloud