1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 2015 Intel Corporation.
5 
6   This program is free software; you can redistribute it and/or modify it
7   under the terms and conditions of the GNU General Public License,
8   version 2, as published by the Free Software Foundation.
9 
10   This program is distributed in the hope it will be useful, but WITHOUT
11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13   more details.
14 
15   You should have received a copy of the GNU General Public License along with
16   this program; if not, write to the Free Software Foundation, Inc.,
17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 
19   The full GNU General Public License is included in this distribution in
20   the file called "COPYING".
21 
22   Contact Information:
23   Linux NICS <linux.nics@intel.com>
24   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
25   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
26 
27 *******************************************************************************/
28 #include "ixgbe.h"
29 #include <linux/ptp_classify.h>
30 #include <linux/clocksource.h>
31 
32 /*
33  * The 82599 and the X540 do not have true 64bit nanosecond scale
34  * counter registers. Instead, SYSTIME is defined by a fixed point
35  * system which allows the user to define the scale counter increment
36  * value at every level change of the oscillator driving the SYSTIME
37  * value. For both devices the TIMINCA:IV field defines this
38  * increment. On the X540 device, 31 bits are provided. However on the
39  * 82599 only provides 24 bits. The time unit is determined by the
40  * clock frequency of the oscillator in combination with the TIMINCA
41  * register. When these devices link at 10Gb the oscillator has a
42  * period of 6.4ns. In order to convert the scale counter into
43  * nanoseconds the cyclecounter and timecounter structures are
44  * used. The SYSTIME registers need to be converted to ns values by use
45  * of only a right shift (division by power of 2). The following math
46  * determines the largest incvalue that will fit into the available
47  * bits in the TIMINCA register.
48  *
49  * PeriodWidth: Number of bits to store the clock period
50  * MaxWidth: The maximum width value of the TIMINCA register
51  * Period: The clock period for the oscillator
52  * round(): discard the fractional portion of the calculation
53  *
54  * Period * [ 2 ^ ( MaxWidth - PeriodWidth ) ]
55  *
56  * For the X540, MaxWidth is 31 bits, and the base period is 6.4 ns
57  * For the 82599, MaxWidth is 24 bits, and the base period is 6.4 ns
58  *
59  * The period also changes based on the link speed:
60  * At 10Gb link or no link, the period remains the same.
61  * At 1Gb link, the period is multiplied by 10. (64ns)
62  * At 100Mb link, the period is multiplied by 100. (640ns)
63  *
64  * The calculated value allows us to right shift the SYSTIME register
65  * value in order to quickly convert it into a nanosecond clock,
66  * while allowing for the maximum possible adjustment value.
67  *
68  * These diagrams are only for the 10Gb link period
69  *
70  *           SYSTIMEH            SYSTIMEL
71  *       +--------------+  +--------------+
72  * X540  |      32      |  | 1 | 3 |  28  |
73  *       *--------------+  +--------------+
74  *        \________ 36 bits ______/  fract
75  *
76  *       +--------------+  +--------------+
77  * 82599 |      32      |  | 8 | 3 |  21  |
78  *       *--------------+  +--------------+
79  *        \________ 43 bits ______/  fract
80  *
81  * The 36 bit X540 SYSTIME overflows every
82  *   2^36 * 10^-9 / 60 = 1.14 minutes or 69 seconds
83  *
84  * The 43 bit 82599 SYSTIME overflows every
85  *   2^43 * 10^-9 / 3600 = 2.4 hours
86  */
87 #define IXGBE_INCVAL_10GB 0x66666666
88 #define IXGBE_INCVAL_1GB  0x40000000
89 #define IXGBE_INCVAL_100  0x50000000
90 
91 #define IXGBE_INCVAL_SHIFT_10GB  28
92 #define IXGBE_INCVAL_SHIFT_1GB   24
93 #define IXGBE_INCVAL_SHIFT_100   21
94 
95 #define IXGBE_INCVAL_SHIFT_82599 7
96 #define IXGBE_INCPER_SHIFT_82599 24
97 
98 #define IXGBE_OVERFLOW_PERIOD    (HZ * 30)
99 #define IXGBE_PTP_TX_TIMEOUT     (HZ * 15)
100 
101 /* half of a one second clock period, for use with PPS signal. We have to use
102  * this instead of something pre-defined like IXGBE_PTP_PPS_HALF_SECOND, in
103  * order to force at least 64bits of precision for shifting
104  */
105 #define IXGBE_PTP_PPS_HALF_SECOND 500000000ULL
106 
107 /* In contrast, the X550 controller has two registers, SYSTIMEH and SYSTIMEL
108  * which contain measurements of seconds and nanoseconds respectively. This
109  * matches the standard linux representation of time in the kernel. In addition,
110  * the X550 also has a SYSTIMER register which represents residue, or
111  * subnanosecond overflow adjustments. To control clock adjustment, the TIMINCA
112  * register is used, but it is unlike the X540 and 82599 devices. TIMINCA
113  * represents units of 2^-32 nanoseconds, and uses 31 bits for this, with the
114  * high bit representing whether the adjustent is positive or negative. Every
115  * clock cycle, the X550 will add 12.5 ns + TIMINCA which can result in a range
116  * of 12 to 13 nanoseconds adjustment. Unlike the 82599 and X540 devices, the
117  * X550's clock for purposes of SYSTIME generation is constant and not dependent
118  * on the link speed.
119  *
120  *           SYSTIMEH           SYSTIMEL        SYSTIMER
121  *       +--------------+  +--------------+  +-------------+
122  * X550  |      32      |  |      32      |  |     32      |
123  *       *--------------+  +--------------+  +-------------+
124  *       \____seconds___/   \_nanoseconds_/  \__2^-32 ns__/
125  *
126  * This results in a full 96 bits to represent the clock, with 32 bits for
127  * seconds, 32 bits for nanoseconds (largest value is 0d999999999 or just under
128  * 1 second) and an additional 32 bits to measure sub nanosecond adjustments for
129  * underflow of adjustments.
130  *
131  * The 32 bits of seconds for the X550 overflows every
132  *   2^32 / ( 365.25 * 24 * 60 * 60 ) = ~136 years.
133  *
134  * In order to adjust the clock frequency for the X550, the TIMINCA register is
135  * provided. This register represents a + or minus nearly 0.5 ns adjustment to
136  * the base frequency. It is measured in 2^-32 ns units, with the high bit being
137  * the sign bit. This register enables software to calculate frequency
138  * adjustments and apply them directly to the clock rate.
139  *
140  * The math for converting ppb into TIMINCA values is fairly straightforward.
141  *   TIMINCA value = ( Base_Frequency * ppb ) / 1000000000ULL
142  *
143  * This assumes that ppb is never high enough to create a value bigger than
144  * TIMINCA's 31 bits can store. This is ensured by the stack. Calculating this
145  * value is also simple.
146  *   Max ppb = ( Max Adjustment / Base Frequency ) / 1000000000ULL
147  *
148  * For the X550, the Max adjustment is +/- 0.5 ns, and the base frequency is
149  * 12.5 nanoseconds. This means that the Max ppb is 39999999
150  *   Note: We subtract one in order to ensure no overflow, because the TIMINCA
151  *         register can only hold slightly under 0.5 nanoseconds.
152  *
153  * Because TIMINCA is measured in 2^-32 ns units, we have to convert 12.5 ns
154  * into 2^-32 units, which is
155  *
156  *  12.5 * 2^32 = C80000000
157  *
158  * Some revisions of hardware have a faster base frequency than the registers
159  * were defined for. To fix this, we use a timecounter structure with the
160  * proper mult and shift to convert the cycles into nanoseconds of time.
161  */
162 #define IXGBE_X550_BASE_PERIOD 0xC80000000ULL
163 #define INCVALUE_MASK	0x7FFFFFFF
164 #define ISGN		0x80000000
165 #define MAX_TIMADJ	0x7FFFFFFF
166 
167 /**
168  * ixgbe_ptp_setup_sdp_x540
169  * @hw: the hardware private structure
170  *
171  * this function enables or disables the clock out feature on SDP0 for
172  * the X540 device. It will create a 1second periodic output that can
173  * be used as the PPS (via an interrupt).
174  *
175  * It calculates when the systime will be on an exact second, and then
176  * aligns the start of the PPS signal to that value. The shift is
177  * necessary because it can change based on the link speed.
178  */
179 static void ixgbe_ptp_setup_sdp_x540(struct ixgbe_adapter *adapter)
180 {
181 	struct ixgbe_hw *hw = &adapter->hw;
182 	int shift = adapter->hw_cc.shift;
183 	u32 esdp, tsauxc, clktiml, clktimh, trgttiml, trgttimh, rem;
184 	u64 ns = 0, clock_edge = 0;
185 
186 	/* disable the pin first */
187 	IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
188 	IXGBE_WRITE_FLUSH(hw);
189 
190 	if (!(adapter->flags2 & IXGBE_FLAG2_PTP_PPS_ENABLED))
191 		return;
192 
193 	esdp = IXGBE_READ_REG(hw, IXGBE_ESDP);
194 
195 	/* enable the SDP0 pin as output, and connected to the
196 	 * native function for Timesync (ClockOut)
197 	 */
198 	esdp |= IXGBE_ESDP_SDP0_DIR |
199 		IXGBE_ESDP_SDP0_NATIVE;
200 
201 	/* enable the Clock Out feature on SDP0, and allow
202 	 * interrupts to occur when the pin changes
203 	 */
204 	tsauxc = IXGBE_TSAUXC_EN_CLK |
205 		 IXGBE_TSAUXC_SYNCLK |
206 		 IXGBE_TSAUXC_SDP0_INT;
207 
208 	/* clock period (or pulse length) */
209 	clktiml = (u32)(IXGBE_PTP_PPS_HALF_SECOND << shift);
210 	clktimh = (u32)((IXGBE_PTP_PPS_HALF_SECOND << shift) >> 32);
211 
212 	/* Account for the cyclecounter wrap-around value by
213 	 * using the converted ns value of the current time to
214 	 * check for when the next aligned second would occur.
215 	 */
216 	clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
217 	clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
218 	ns = timecounter_cyc2time(&adapter->hw_tc, clock_edge);
219 
220 	div_u64_rem(ns, IXGBE_PTP_PPS_HALF_SECOND, &rem);
221 	clock_edge += ((IXGBE_PTP_PPS_HALF_SECOND - (u64)rem) << shift);
222 
223 	/* specify the initial clock start time */
224 	trgttiml = (u32)clock_edge;
225 	trgttimh = (u32)(clock_edge >> 32);
226 
227 	IXGBE_WRITE_REG(hw, IXGBE_CLKTIML, clktiml);
228 	IXGBE_WRITE_REG(hw, IXGBE_CLKTIMH, clktimh);
229 	IXGBE_WRITE_REG(hw, IXGBE_TRGTTIML0, trgttiml);
230 	IXGBE_WRITE_REG(hw, IXGBE_TRGTTIMH0, trgttimh);
231 
232 	IXGBE_WRITE_REG(hw, IXGBE_ESDP, esdp);
233 	IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, tsauxc);
234 
235 	IXGBE_WRITE_FLUSH(hw);
236 }
237 
238 /**
239  * ixgbe_ptp_read_X550 - read cycle counter value
240  * @hw_cc: cyclecounter structure
241  *
242  * This function reads SYSTIME registers. It is called by the cyclecounter
243  * structure to convert from internal representation into nanoseconds. We need
244  * this for X550 since some skews do not have expected clock frequency and
245  * result of SYSTIME is 32bits of "billions of cycles" and 32 bits of
246  * "cycles", rather than seconds and nanoseconds.
247  */
248 static cycle_t ixgbe_ptp_read_X550(const struct cyclecounter *hw_cc)
249 {
250 	struct ixgbe_adapter *adapter =
251 			container_of(hw_cc, struct ixgbe_adapter, hw_cc);
252 	struct ixgbe_hw *hw = &adapter->hw;
253 	struct timespec64 ts;
254 
255 	/* storage is 32 bits of 'billions of cycles' and 32 bits of 'cycles'.
256 	 * Some revisions of hardware run at a higher frequency and so the
257 	 * cycles are not guaranteed to be nanoseconds. The timespec64 created
258 	 * here is used for its math/conversions but does not necessarily
259 	 * represent nominal time.
260 	 *
261 	 * It should be noted that this cyclecounter will overflow at a
262 	 * non-bitmask field since we have to convert our billions of cycles
263 	 * into an actual cycles count. This results in some possible weird
264 	 * situations at high cycle counter stamps. However given that 32 bits
265 	 * of "seconds" is ~138 years this isn't a problem. Even at the
266 	 * increased frequency of some revisions, this is still ~103 years.
267 	 * Since the SYSTIME values start at 0 and we never write them, it is
268 	 * highly unlikely for the cyclecounter to overflow in practice.
269 	 */
270 	IXGBE_READ_REG(hw, IXGBE_SYSTIMR);
271 	ts.tv_nsec = IXGBE_READ_REG(hw, IXGBE_SYSTIML);
272 	ts.tv_sec = IXGBE_READ_REG(hw, IXGBE_SYSTIMH);
273 
274 	return (u64)timespec64_to_ns(&ts);
275 }
276 
277 /**
278  * ixgbe_ptp_read_82599 - read raw cycle counter (to be used by time counter)
279  * @cc: the cyclecounter structure
280  *
281  * this function reads the cyclecounter registers and is called by the
282  * cyclecounter structure used to construct a ns counter from the
283  * arbitrary fixed point registers
284  */
285 static cycle_t ixgbe_ptp_read_82599(const struct cyclecounter *cc)
286 {
287 	struct ixgbe_adapter *adapter =
288 		container_of(cc, struct ixgbe_adapter, hw_cc);
289 	struct ixgbe_hw *hw = &adapter->hw;
290 	u64 stamp = 0;
291 
292 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
293 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
294 
295 	return stamp;
296 }
297 
298 /**
299  * ixgbe_ptp_convert_to_hwtstamp - convert register value to hw timestamp
300  * @adapter: private adapter structure
301  * @hwtstamp: stack timestamp structure
302  * @systim: unsigned 64bit system time value
303  *
304  * We need to convert the adapter's RX/TXSTMP registers into a hwtstamp value
305  * which can be used by the stack's ptp functions.
306  *
307  * The lock is used to protect consistency of the cyclecounter and the SYSTIME
308  * registers. However, it does not need to protect against the Rx or Tx
309  * timestamp registers, as there can't be a new timestamp until the old one is
310  * unlatched by reading.
311  *
312  * In addition to the timestamp in hardware, some controllers need a software
313  * overflow cyclecounter, and this function takes this into account as well.
314  **/
315 static void ixgbe_ptp_convert_to_hwtstamp(struct ixgbe_adapter *adapter,
316 					  struct skb_shared_hwtstamps *hwtstamp,
317 					  u64 timestamp)
318 {
319 	unsigned long flags;
320 	struct timespec64 systime;
321 	u64 ns;
322 
323 	memset(hwtstamp, 0, sizeof(*hwtstamp));
324 
325 	switch (adapter->hw.mac.type) {
326 	/* X550 and later hardware supposedly represent time using a seconds
327 	 * and nanoseconds counter, instead of raw 64bits nanoseconds. We need
328 	 * to convert the timestamp into cycles before it can be fed to the
329 	 * cyclecounter. We need an actual cyclecounter because some revisions
330 	 * of hardware run at a higher frequency and thus the counter does
331 	 * not represent seconds/nanoseconds. Instead it can be thought of as
332 	 * cycles and billions of cycles.
333 	 */
334 	case ixgbe_mac_X550:
335 	case ixgbe_mac_X550EM_x:
336 		/* Upper 32 bits represent billions of cycles, lower 32 bits
337 		 * represent cycles. However, we use timespec64_to_ns for the
338 		 * correct math even though the units haven't been corrected
339 		 * yet.
340 		 */
341 		systime.tv_sec = timestamp >> 32;
342 		systime.tv_nsec = timestamp & 0xFFFFFFFF;
343 
344 		timestamp = timespec64_to_ns(&systime);
345 		break;
346 	default:
347 		break;
348 	}
349 
350 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
351 	ns = timecounter_cyc2time(&adapter->hw_tc, timestamp);
352 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
353 
354 	hwtstamp->hwtstamp = ns_to_ktime(ns);
355 }
356 
357 /**
358  * ixgbe_ptp_adjfreq_82599
359  * @ptp: the ptp clock structure
360  * @ppb: parts per billion adjustment from base
361  *
362  * adjust the frequency of the ptp cycle counter by the
363  * indicated ppb from the base frequency.
364  */
365 static int ixgbe_ptp_adjfreq_82599(struct ptp_clock_info *ptp, s32 ppb)
366 {
367 	struct ixgbe_adapter *adapter =
368 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
369 	struct ixgbe_hw *hw = &adapter->hw;
370 	u64 freq, incval;
371 	u32 diff;
372 	int neg_adj = 0;
373 
374 	if (ppb < 0) {
375 		neg_adj = 1;
376 		ppb = -ppb;
377 	}
378 
379 	smp_mb();
380 	incval = ACCESS_ONCE(adapter->base_incval);
381 
382 	freq = incval;
383 	freq *= ppb;
384 	diff = div_u64(freq, 1000000000ULL);
385 
386 	incval = neg_adj ? (incval - diff) : (incval + diff);
387 
388 	switch (hw->mac.type) {
389 	case ixgbe_mac_X540:
390 		if (incval > 0xFFFFFFFFULL)
391 			e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
392 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, (u32)incval);
393 		break;
394 	case ixgbe_mac_82599EB:
395 		if (incval > 0x00FFFFFFULL)
396 			e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
397 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
398 				(1 << IXGBE_INCPER_SHIFT_82599) |
399 				((u32)incval & 0x00FFFFFFUL));
400 		break;
401 	default:
402 		break;
403 	}
404 
405 	return 0;
406 }
407 
408 /**
409  * ixgbe_ptp_adjfreq_X550
410  * @ptp: the ptp clock structure
411  * @ppb: parts per billion adjustment from base
412  *
413  * adjust the frequency of the SYSTIME registers by the indicated ppb from base
414  * frequency
415  */
416 static int ixgbe_ptp_adjfreq_X550(struct ptp_clock_info *ptp, s32 ppb)
417 {
418 	struct ixgbe_adapter *adapter =
419 			container_of(ptp, struct ixgbe_adapter, ptp_caps);
420 	struct ixgbe_hw *hw = &adapter->hw;
421 	int neg_adj = 0;
422 	u64 rate = IXGBE_X550_BASE_PERIOD;
423 	u32 inca;
424 
425 	if (ppb < 0) {
426 		neg_adj = 1;
427 		ppb = -ppb;
428 	}
429 	rate *= ppb;
430 	rate = div_u64(rate, 1000000000ULL);
431 
432 	/* warn if rate is too large */
433 	if (rate >= INCVALUE_MASK)
434 		e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
435 
436 	inca = rate & INCVALUE_MASK;
437 	if (neg_adj)
438 		inca |= ISGN;
439 
440 	IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, inca);
441 
442 	return 0;
443 }
444 
445 /**
446  * ixgbe_ptp_adjtime
447  * @ptp: the ptp clock structure
448  * @delta: offset to adjust the cycle counter by
449  *
450  * adjust the timer by resetting the timecounter structure.
451  */
452 static int ixgbe_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
453 {
454 	struct ixgbe_adapter *adapter =
455 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
456 	unsigned long flags;
457 
458 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
459 	timecounter_adjtime(&adapter->hw_tc, delta);
460 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
461 
462 	if (adapter->ptp_setup_sdp)
463 		adapter->ptp_setup_sdp(adapter);
464 
465 	return 0;
466 }
467 
468 /**
469  * ixgbe_ptp_gettime
470  * @ptp: the ptp clock structure
471  * @ts: timespec structure to hold the current time value
472  *
473  * read the timecounter and return the correct value on ns,
474  * after converting it into a struct timespec.
475  */
476 static int ixgbe_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
477 {
478 	struct ixgbe_adapter *adapter =
479 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
480 	unsigned long flags;
481 	u64 ns;
482 
483 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
484 	ns = timecounter_read(&adapter->hw_tc);
485 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
486 
487 	*ts = ns_to_timespec64(ns);
488 
489 	return 0;
490 }
491 
492 /**
493  * ixgbe_ptp_settime
494  * @ptp: the ptp clock structure
495  * @ts: the timespec containing the new time for the cycle counter
496  *
497  * reset the timecounter to use a new base value instead of the kernel
498  * wall timer value.
499  */
500 static int ixgbe_ptp_settime(struct ptp_clock_info *ptp,
501 			     const struct timespec64 *ts)
502 {
503 	struct ixgbe_adapter *adapter =
504 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
505 	unsigned long flags;
506 	u64 ns = timespec64_to_ns(ts);
507 
508 	/* reset the timecounter */
509 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
510 	timecounter_init(&adapter->hw_tc, &adapter->hw_cc, ns);
511 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
512 
513 	if (adapter->ptp_setup_sdp)
514 		adapter->ptp_setup_sdp(adapter);
515 	return 0;
516 }
517 
518 /**
519  * ixgbe_ptp_feature_enable
520  * @ptp: the ptp clock structure
521  * @rq: the requested feature to change
522  * @on: whether to enable or disable the feature
523  *
524  * enable (or disable) ancillary features of the phc subsystem.
525  * our driver only supports the PPS feature on the X540
526  */
527 static int ixgbe_ptp_feature_enable(struct ptp_clock_info *ptp,
528 				    struct ptp_clock_request *rq, int on)
529 {
530 	struct ixgbe_adapter *adapter =
531 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
532 
533 	/**
534 	 * When PPS is enabled, unmask the interrupt for the ClockOut
535 	 * feature, so that the interrupt handler can send the PPS
536 	 * event when the clock SDP triggers. Clear mask when PPS is
537 	 * disabled
538 	 */
539 	if (rq->type != PTP_CLK_REQ_PPS || !adapter->ptp_setup_sdp)
540 		return -ENOTSUPP;
541 
542 	if (on)
543 		adapter->flags2 |= IXGBE_FLAG2_PTP_PPS_ENABLED;
544 	else
545 		adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
546 
547 	adapter->ptp_setup_sdp(adapter);
548 	return 0;
549 }
550 
551 /**
552  * ixgbe_ptp_check_pps_event
553  * @adapter: the private adapter structure
554  *
555  * This function is called by the interrupt routine when checking for
556  * interrupts. It will check and handle a pps event.
557  */
558 void ixgbe_ptp_check_pps_event(struct ixgbe_adapter *adapter)
559 {
560 	struct ixgbe_hw *hw = &adapter->hw;
561 	struct ptp_clock_event event;
562 
563 	event.type = PTP_CLOCK_PPS;
564 
565 	/* this check is necessary in case the interrupt was enabled via some
566 	 * alternative means (ex. debug_fs). Better to check here than
567 	 * everywhere that calls this function.
568 	 */
569 	if (!adapter->ptp_clock)
570 		return;
571 
572 	switch (hw->mac.type) {
573 	case ixgbe_mac_X540:
574 		ptp_clock_event(adapter->ptp_clock, &event);
575 		break;
576 	default:
577 		break;
578 	}
579 }
580 
581 /**
582  * ixgbe_ptp_overflow_check - watchdog task to detect SYSTIME overflow
583  * @adapter: private adapter struct
584  *
585  * this watchdog task periodically reads the timecounter
586  * in order to prevent missing when the system time registers wrap
587  * around. This needs to be run approximately twice a minute.
588  */
589 void ixgbe_ptp_overflow_check(struct ixgbe_adapter *adapter)
590 {
591 	bool timeout = time_is_before_jiffies(adapter->last_overflow_check +
592 					     IXGBE_OVERFLOW_PERIOD);
593 	struct timespec64 ts;
594 
595 	if (timeout) {
596 		ixgbe_ptp_gettime(&adapter->ptp_caps, &ts);
597 		adapter->last_overflow_check = jiffies;
598 	}
599 }
600 
601 /**
602  * ixgbe_ptp_rx_hang - detect error case when Rx timestamp registers latched
603  * @adapter: private network adapter structure
604  *
605  * this watchdog task is scheduled to detect error case where hardware has
606  * dropped an Rx packet that was timestamped when the ring is full. The
607  * particular error is rare but leaves the device in a state unable to timestamp
608  * any future packets.
609  */
610 void ixgbe_ptp_rx_hang(struct ixgbe_adapter *adapter)
611 {
612 	struct ixgbe_hw *hw = &adapter->hw;
613 	u32 tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
614 	struct ixgbe_ring *rx_ring;
615 	unsigned long rx_event;
616 	int n;
617 
618 	/* if we don't have a valid timestamp in the registers, just update the
619 	 * timeout counter and exit
620 	 */
621 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID)) {
622 		adapter->last_rx_ptp_check = jiffies;
623 		return;
624 	}
625 
626 	/* determine the most recent watchdog or rx_timestamp event */
627 	rx_event = adapter->last_rx_ptp_check;
628 	for (n = 0; n < adapter->num_rx_queues; n++) {
629 		rx_ring = adapter->rx_ring[n];
630 		if (time_after(rx_ring->last_rx_timestamp, rx_event))
631 			rx_event = rx_ring->last_rx_timestamp;
632 	}
633 
634 	/* only need to read the high RXSTMP register to clear the lock */
635 	if (time_is_before_jiffies(rx_event + 5 * HZ)) {
636 		IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
637 		adapter->last_rx_ptp_check = jiffies;
638 
639 		adapter->rx_hwtstamp_cleared++;
640 		e_warn(drv, "clearing RX Timestamp hang\n");
641 	}
642 }
643 
644 /**
645  * ixgbe_ptp_clear_tx_timestamp - utility function to clear Tx timestamp state
646  * @adapter: the private adapter structure
647  *
648  * This function should be called whenever the state related to a Tx timestamp
649  * needs to be cleared. This helps ensure that all related bits are reset for
650  * the next Tx timestamp event.
651  */
652 static void ixgbe_ptp_clear_tx_timestamp(struct ixgbe_adapter *adapter)
653 {
654 	struct ixgbe_hw *hw = &adapter->hw;
655 
656 	IXGBE_READ_REG(hw, IXGBE_TXSTMPH);
657 	if (adapter->ptp_tx_skb) {
658 		dev_kfree_skb_any(adapter->ptp_tx_skb);
659 		adapter->ptp_tx_skb = NULL;
660 	}
661 	clear_bit_unlock(__IXGBE_PTP_TX_IN_PROGRESS, &adapter->state);
662 }
663 
664 /**
665  * ixgbe_ptp_tx_hwtstamp - utility function which checks for TX time stamp
666  * @adapter: the private adapter struct
667  *
668  * if the timestamp is valid, we convert it into the timecounter ns
669  * value, then store that result into the shhwtstamps structure which
670  * is passed up the network stack
671  */
672 static void ixgbe_ptp_tx_hwtstamp(struct ixgbe_adapter *adapter)
673 {
674 	struct ixgbe_hw *hw = &adapter->hw;
675 	struct skb_shared_hwtstamps shhwtstamps;
676 	u64 regval = 0;
677 
678 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPL);
679 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPH) << 32;
680 
681 	ixgbe_ptp_convert_to_hwtstamp(adapter, &shhwtstamps, regval);
682 	skb_tstamp_tx(adapter->ptp_tx_skb, &shhwtstamps);
683 
684 	ixgbe_ptp_clear_tx_timestamp(adapter);
685 }
686 
687 /**
688  * ixgbe_ptp_tx_hwtstamp_work
689  * @work: pointer to the work struct
690  *
691  * This work item polls TSYNCTXCTL valid bit to determine when a Tx hardware
692  * timestamp has been taken for the current skb. It is necessary, because the
693  * descriptor's "done" bit does not correlate with the timestamp event.
694  */
695 static void ixgbe_ptp_tx_hwtstamp_work(struct work_struct *work)
696 {
697 	struct ixgbe_adapter *adapter = container_of(work, struct ixgbe_adapter,
698 						     ptp_tx_work);
699 	struct ixgbe_hw *hw = &adapter->hw;
700 	bool timeout = time_is_before_jiffies(adapter->ptp_tx_start +
701 					      IXGBE_PTP_TX_TIMEOUT);
702 	u32 tsynctxctl;
703 
704 	/* we have to have a valid skb to poll for a timestamp */
705 	if (!adapter->ptp_tx_skb) {
706 		ixgbe_ptp_clear_tx_timestamp(adapter);
707 		return;
708 	}
709 
710 	/* stop polling once we have a valid timestamp */
711 	tsynctxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
712 	if (tsynctxctl & IXGBE_TSYNCTXCTL_VALID) {
713 		ixgbe_ptp_tx_hwtstamp(adapter);
714 		return;
715 	}
716 
717 	if (timeout) {
718 		ixgbe_ptp_clear_tx_timestamp(adapter);
719 		adapter->tx_hwtstamp_timeouts++;
720 		e_warn(drv, "clearing Tx Timestamp hang\n");
721 	} else {
722 		/* reschedule to keep checking if it's not available yet */
723 		schedule_work(&adapter->ptp_tx_work);
724 	}
725 }
726 
727 /**
728  * ixgbe_ptp_rx_pktstamp - utility function to get RX time stamp from buffer
729  * @q_vector: structure containing interrupt and ring information
730  * @skb: the packet
731  *
732  * This function will be called by the Rx routine of the timestamp for this
733  * packet is stored in the buffer. The value is stored in little endian format
734  * starting at the end of the packet data.
735  */
736 void ixgbe_ptp_rx_pktstamp(struct ixgbe_q_vector *q_vector,
737 			   struct sk_buff *skb)
738 {
739 	__le64 regval;
740 
741 	/* copy the bits out of the skb, and then trim the skb length */
742 	skb_copy_bits(skb, skb->len - IXGBE_TS_HDR_LEN, &regval,
743 		      IXGBE_TS_HDR_LEN);
744 	__pskb_trim(skb, skb->len - IXGBE_TS_HDR_LEN);
745 
746 	/* The timestamp is recorded in little endian format, and is stored at
747 	 * the end of the packet.
748 	 *
749 	 * DWORD: N              N + 1      N + 2
750 	 * Field: End of Packet  SYSTIMH    SYSTIML
751 	 */
752 	ixgbe_ptp_convert_to_hwtstamp(q_vector->adapter, skb_hwtstamps(skb),
753 				      le64_to_cpu(regval));
754 }
755 
756 /**
757  * ixgbe_ptp_rx_rgtstamp - utility function which checks for RX time stamp
758  * @q_vector: structure containing interrupt and ring information
759  * @skb: particular skb to send timestamp with
760  *
761  * if the timestamp is valid, we convert it into the timecounter ns
762  * value, then store that result into the shhwtstamps structure which
763  * is passed up the network stack
764  */
765 void ixgbe_ptp_rx_rgtstamp(struct ixgbe_q_vector *q_vector,
766 			   struct sk_buff *skb)
767 {
768 	struct ixgbe_adapter *adapter;
769 	struct ixgbe_hw *hw;
770 	u64 regval = 0;
771 	u32 tsyncrxctl;
772 
773 	/* we cannot process timestamps on a ring without a q_vector */
774 	if (!q_vector || !q_vector->adapter)
775 		return;
776 
777 	adapter = q_vector->adapter;
778 	hw = &adapter->hw;
779 
780 	/* Read the tsyncrxctl register afterwards in order to prevent taking an
781 	 * I/O hit on every packet.
782 	 */
783 
784 	tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
785 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID))
786 		return;
787 
788 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPL);
789 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPH) << 32;
790 
791 	ixgbe_ptp_convert_to_hwtstamp(adapter, skb_hwtstamps(skb), regval);
792 }
793 
794 int ixgbe_ptp_get_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
795 {
796 	struct hwtstamp_config *config = &adapter->tstamp_config;
797 
798 	return copy_to_user(ifr->ifr_data, config,
799 			    sizeof(*config)) ? -EFAULT : 0;
800 }
801 
802 /**
803  * ixgbe_ptp_set_timestamp_mode - setup the hardware for the requested mode
804  * @adapter: the private ixgbe adapter structure
805  * @config: the hwtstamp configuration requested
806  *
807  * Outgoing time stamping can be enabled and disabled. Play nice and
808  * disable it when requested, although it shouldn't cause any overhead
809  * when no packet needs it. At most one packet in the queue may be
810  * marked for time stamping, otherwise it would be impossible to tell
811  * for sure to which packet the hardware time stamp belongs.
812  *
813  * Incoming time stamping has to be configured via the hardware
814  * filters. Not all combinations are supported, in particular event
815  * type has to be specified. Matching the kind of event packet is
816  * not supported, with the exception of "all V2 events regardless of
817  * level 2 or 4".
818  *
819  * Since hardware always timestamps Path delay packets when timestamping V2
820  * packets, regardless of the type specified in the register, only use V2
821  * Event mode. This more accurately tells the user what the hardware is going
822  * to do anyways.
823  *
824  * Note: this may modify the hwtstamp configuration towards a more general
825  * mode, if required to support the specifically requested mode.
826  */
827 static int ixgbe_ptp_set_timestamp_mode(struct ixgbe_adapter *adapter,
828 				 struct hwtstamp_config *config)
829 {
830 	struct ixgbe_hw *hw = &adapter->hw;
831 	u32 tsync_tx_ctl = IXGBE_TSYNCTXCTL_ENABLED;
832 	u32 tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED;
833 	u32 tsync_rx_mtrl = PTP_EV_PORT << 16;
834 	bool is_l2 = false;
835 	u32 regval;
836 
837 	/* reserved for future extensions */
838 	if (config->flags)
839 		return -EINVAL;
840 
841 	switch (config->tx_type) {
842 	case HWTSTAMP_TX_OFF:
843 		tsync_tx_ctl = 0;
844 	case HWTSTAMP_TX_ON:
845 		break;
846 	default:
847 		return -ERANGE;
848 	}
849 
850 	switch (config->rx_filter) {
851 	case HWTSTAMP_FILTER_NONE:
852 		tsync_rx_ctl = 0;
853 		tsync_rx_mtrl = 0;
854 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
855 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
856 		break;
857 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
858 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
859 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_SYNC_MSG;
860 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
861 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
862 		break;
863 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
864 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
865 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_DELAY_REQ_MSG;
866 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
867 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
868 		break;
869 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
870 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
871 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
872 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
873 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
874 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
875 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
876 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
877 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
878 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_EVENT_V2;
879 		is_l2 = true;
880 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
881 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
882 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
883 		break;
884 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
885 	case HWTSTAMP_FILTER_ALL:
886 		/* The X550 controller is capable of timestamping all packets,
887 		 * which allows it to accept any filter.
888 		 */
889 		if (hw->mac.type >= ixgbe_mac_X550) {
890 			tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_ALL;
891 			config->rx_filter = HWTSTAMP_FILTER_ALL;
892 			adapter->flags |= IXGBE_FLAG_RX_HWTSTAMP_ENABLED;
893 			break;
894 		}
895 		/* fall through */
896 	default:
897 		/*
898 		 * register RXMTRL must be set in order to do V1 packets,
899 		 * therefore it is not possible to time stamp both V1 Sync and
900 		 * Delay_Req messages and hardware does not support
901 		 * timestamping all packets => return error
902 		 */
903 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
904 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
905 		config->rx_filter = HWTSTAMP_FILTER_NONE;
906 		return -ERANGE;
907 	}
908 
909 	if (hw->mac.type == ixgbe_mac_82598EB) {
910 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
911 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
912 		if (tsync_rx_ctl | tsync_tx_ctl)
913 			return -ERANGE;
914 		return 0;
915 	}
916 
917 	/* Per-packet timestamping only works if the filter is set to all
918 	 * packets. Since this is desired, always timestamp all packets as long
919 	 * as any Rx filter was configured.
920 	 */
921 	switch (hw->mac.type) {
922 	case ixgbe_mac_X550:
923 	case ixgbe_mac_X550EM_x:
924 		/* enable timestamping all packets only if at least some
925 		 * packets were requested. Otherwise, play nice and disable
926 		 * timestamping
927 		 */
928 		if (config->rx_filter == HWTSTAMP_FILTER_NONE)
929 			break;
930 
931 		tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED |
932 			       IXGBE_TSYNCRXCTL_TYPE_ALL |
933 			       IXGBE_TSYNCRXCTL_TSIP_UT_EN;
934 		config->rx_filter = HWTSTAMP_FILTER_ALL;
935 		adapter->flags |= IXGBE_FLAG_RX_HWTSTAMP_ENABLED;
936 		adapter->flags &= ~IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER;
937 		is_l2 = true;
938 		break;
939 	default:
940 		break;
941 	}
942 
943 	/* define ethertype filter for timestamping L2 packets */
944 	if (is_l2)
945 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
946 				(IXGBE_ETQF_FILTER_EN | /* enable filter */
947 				 IXGBE_ETQF_1588 | /* enable timestamping */
948 				 ETH_P_1588));     /* 1588 eth protocol type */
949 	else
950 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588), 0);
951 
952 	/* enable/disable TX */
953 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
954 	regval &= ~IXGBE_TSYNCTXCTL_ENABLED;
955 	regval |= tsync_tx_ctl;
956 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCTXCTL, regval);
957 
958 	/* enable/disable RX */
959 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
960 	regval &= ~(IXGBE_TSYNCRXCTL_ENABLED | IXGBE_TSYNCRXCTL_TYPE_MASK);
961 	regval |= tsync_rx_ctl;
962 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, regval);
963 
964 	/* define which PTP packets are time stamped */
965 	IXGBE_WRITE_REG(hw, IXGBE_RXMTRL, tsync_rx_mtrl);
966 
967 	IXGBE_WRITE_FLUSH(hw);
968 
969 	/* clear TX/RX time stamp registers, just to be sure */
970 	ixgbe_ptp_clear_tx_timestamp(adapter);
971 	IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
972 
973 	return 0;
974 }
975 
976 /**
977  * ixgbe_ptp_set_ts_config - user entry point for timestamp mode
978  * @adapter: pointer to adapter struct
979  * @ifreq: ioctl data
980  *
981  * Set hardware to requested mode. If unsupported, return an error with no
982  * changes. Otherwise, store the mode for future reference.
983  */
984 int ixgbe_ptp_set_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
985 {
986 	struct hwtstamp_config config;
987 	int err;
988 
989 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
990 		return -EFAULT;
991 
992 	err = ixgbe_ptp_set_timestamp_mode(adapter, &config);
993 	if (err)
994 		return err;
995 
996 	/* save these settings for future reference */
997 	memcpy(&adapter->tstamp_config, &config,
998 	       sizeof(adapter->tstamp_config));
999 
1000 	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
1001 		-EFAULT : 0;
1002 }
1003 
1004 static void ixgbe_ptp_link_speed_adjust(struct ixgbe_adapter *adapter,
1005 					u32 *shift, u32 *incval)
1006 {
1007 	/**
1008 	 * Scale the NIC cycle counter by a large factor so that
1009 	 * relatively small corrections to the frequency can be added
1010 	 * or subtracted. The drawbacks of a large factor include
1011 	 * (a) the clock register overflows more quickly, (b) the cycle
1012 	 * counter structure must be able to convert the systime value
1013 	 * to nanoseconds using only a multiplier and a right-shift,
1014 	 * and (c) the value must fit within the timinca register space
1015 	 * => math based on internal DMA clock rate and available bits
1016 	 *
1017 	 * Note that when there is no link, internal DMA clock is same as when
1018 	 * link speed is 10Gb. Set the registers correctly even when link is
1019 	 * down to preserve the clock setting
1020 	 */
1021 	switch (adapter->link_speed) {
1022 	case IXGBE_LINK_SPEED_100_FULL:
1023 		*shift = IXGBE_INCVAL_SHIFT_100;
1024 		*incval = IXGBE_INCVAL_100;
1025 		break;
1026 	case IXGBE_LINK_SPEED_1GB_FULL:
1027 		*shift = IXGBE_INCVAL_SHIFT_1GB;
1028 		*incval = IXGBE_INCVAL_1GB;
1029 		break;
1030 	case IXGBE_LINK_SPEED_10GB_FULL:
1031 	default:
1032 		*shift = IXGBE_INCVAL_SHIFT_10GB;
1033 		*incval = IXGBE_INCVAL_10GB;
1034 		break;
1035 	}
1036 }
1037 
1038 /**
1039  * ixgbe_ptp_start_cyclecounter - create the cycle counter from hw
1040  * @adapter: pointer to the adapter structure
1041  *
1042  * This function should be called to set the proper values for the TIMINCA
1043  * register and tell the cyclecounter structure what the tick rate of SYSTIME
1044  * is. It does not directly modify SYSTIME registers or the timecounter
1045  * structure. It should be called whenever a new TIMINCA value is necessary,
1046  * such as during initialization or when the link speed changes.
1047  */
1048 void ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter *adapter)
1049 {
1050 	struct ixgbe_hw *hw = &adapter->hw;
1051 	struct cyclecounter cc;
1052 	unsigned long flags;
1053 	u32 incval = 0;
1054 	u32 tsauxc = 0;
1055 	u32 fuse0 = 0;
1056 
1057 	/* For some of the boards below this mask is technically incorrect.
1058 	 * The timestamp mask overflows at approximately 61bits. However the
1059 	 * particular hardware does not overflow on an even bitmask value.
1060 	 * Instead, it overflows due to conversion of upper 32bits billions of
1061 	 * cycles. Timecounters are not really intended for this purpose so
1062 	 * they do not properly function if the overflow point isn't 2^N-1.
1063 	 * However, the actual SYSTIME values in question take ~138 years to
1064 	 * overflow. In practice this means they won't actually overflow. A
1065 	 * proper fix to this problem would require modification of the
1066 	 * timecounter delta calculations.
1067 	 */
1068 	cc.mask = CLOCKSOURCE_MASK(64);
1069 	cc.mult = 1;
1070 	cc.shift = 0;
1071 
1072 	switch (hw->mac.type) {
1073 	case ixgbe_mac_X550EM_x:
1074 		/* SYSTIME assumes X550EM_x board frequency is 300Mhz, and is
1075 		 * designed to represent seconds and nanoseconds when this is
1076 		 * the case. However, some revisions of hardware have a 400Mhz
1077 		 * clock and we have to compensate for this frequency
1078 		 * variation using corrected mult and shift values.
1079 		 */
1080 		fuse0 = IXGBE_READ_REG(hw, IXGBE_FUSES0_GROUP(0));
1081 		if (!(fuse0 & IXGBE_FUSES0_300MHZ)) {
1082 			cc.mult = 3;
1083 			cc.shift = 2;
1084 		}
1085 		/* fallthrough */
1086 	case ixgbe_mac_X550:
1087 		cc.read = ixgbe_ptp_read_X550;
1088 
1089 		/* enable SYSTIME counter */
1090 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIMR, 0);
1091 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIML, 0);
1092 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIMH, 0);
1093 		tsauxc = IXGBE_READ_REG(hw, IXGBE_TSAUXC);
1094 		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC,
1095 				tsauxc & ~IXGBE_TSAUXC_DISABLE_SYSTIME);
1096 		IXGBE_WRITE_REG(hw, IXGBE_TSIM, IXGBE_TSIM_TXTS);
1097 		IXGBE_WRITE_REG(hw, IXGBE_EIMS, IXGBE_EIMS_TIMESYNC);
1098 
1099 		IXGBE_WRITE_FLUSH(hw);
1100 		break;
1101 	case ixgbe_mac_X540:
1102 		cc.read = ixgbe_ptp_read_82599;
1103 
1104 		ixgbe_ptp_link_speed_adjust(adapter, &cc.shift, &incval);
1105 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
1106 		break;
1107 	case ixgbe_mac_82599EB:
1108 		cc.read = ixgbe_ptp_read_82599;
1109 
1110 		ixgbe_ptp_link_speed_adjust(adapter, &cc.shift, &incval);
1111 		incval >>= IXGBE_INCVAL_SHIFT_82599;
1112 		cc.shift -= IXGBE_INCVAL_SHIFT_82599;
1113 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
1114 				(1 << IXGBE_INCPER_SHIFT_82599) | incval);
1115 		break;
1116 	default:
1117 		/* other devices aren't supported */
1118 		return;
1119 	}
1120 
1121 	/* update the base incval used to calculate frequency adjustment */
1122 	ACCESS_ONCE(adapter->base_incval) = incval;
1123 	smp_mb();
1124 
1125 	/* need lock to prevent incorrect read while modifying cyclecounter */
1126 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
1127 	memcpy(&adapter->hw_cc, &cc, sizeof(adapter->hw_cc));
1128 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
1129 }
1130 
1131 /**
1132  * ixgbe_ptp_reset
1133  * @adapter: the ixgbe private board structure
1134  *
1135  * When the MAC resets, all the hardware bits for timesync are reset. This
1136  * function is used to re-enable the device for PTP based on current settings.
1137  * We do lose the current clock time, so just reset the cyclecounter to the
1138  * system real clock time.
1139  *
1140  * This function will maintain hwtstamp_config settings, and resets the SDP
1141  * output if it was enabled.
1142  */
1143 void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
1144 {
1145 	struct ixgbe_hw *hw = &adapter->hw;
1146 	unsigned long flags;
1147 
1148 	/* reset the hardware timestamping mode */
1149 	ixgbe_ptp_set_timestamp_mode(adapter, &adapter->tstamp_config);
1150 
1151 	/* 82598 does not support PTP */
1152 	if (hw->mac.type == ixgbe_mac_82598EB)
1153 		return;
1154 
1155 	ixgbe_ptp_start_cyclecounter(adapter);
1156 
1157 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
1158 	timecounter_init(&adapter->hw_tc, &adapter->hw_cc,
1159 			 ktime_to_ns(ktime_get_real()));
1160 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
1161 
1162 	adapter->last_overflow_check = jiffies;
1163 
1164 	/* Now that the shift has been calculated and the systime
1165 	 * registers reset, (re-)enable the Clock out feature
1166 	 */
1167 	if (adapter->ptp_setup_sdp)
1168 		adapter->ptp_setup_sdp(adapter);
1169 }
1170 
1171 /**
1172  * ixgbe_ptp_create_clock
1173  * @adapter: the ixgbe private adapter structure
1174  *
1175  * This function performs setup of the user entry point function table and
1176  * initializes the PTP clock device, which is used to access the clock-like
1177  * features of the PTP core. It will be called by ixgbe_ptp_init, and may
1178  * reuse a previously initialized clock (such as during a suspend/resume
1179  * cycle).
1180  */
1181 static long ixgbe_ptp_create_clock(struct ixgbe_adapter *adapter)
1182 {
1183 	struct net_device *netdev = adapter->netdev;
1184 	long err;
1185 
1186 	/* do nothing if we already have a clock device */
1187 	if (!IS_ERR_OR_NULL(adapter->ptp_clock))
1188 		return 0;
1189 
1190 	switch (adapter->hw.mac.type) {
1191 	case ixgbe_mac_X540:
1192 		snprintf(adapter->ptp_caps.name,
1193 			 sizeof(adapter->ptp_caps.name),
1194 			 "%s", netdev->name);
1195 		adapter->ptp_caps.owner = THIS_MODULE;
1196 		adapter->ptp_caps.max_adj = 250000000;
1197 		adapter->ptp_caps.n_alarm = 0;
1198 		adapter->ptp_caps.n_ext_ts = 0;
1199 		adapter->ptp_caps.n_per_out = 0;
1200 		adapter->ptp_caps.pps = 1;
1201 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_82599;
1202 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1203 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1204 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1205 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1206 		adapter->ptp_setup_sdp = ixgbe_ptp_setup_sdp_x540;
1207 		break;
1208 	case ixgbe_mac_82599EB:
1209 		snprintf(adapter->ptp_caps.name,
1210 			 sizeof(adapter->ptp_caps.name),
1211 			 "%s", netdev->name);
1212 		adapter->ptp_caps.owner = THIS_MODULE;
1213 		adapter->ptp_caps.max_adj = 250000000;
1214 		adapter->ptp_caps.n_alarm = 0;
1215 		adapter->ptp_caps.n_ext_ts = 0;
1216 		adapter->ptp_caps.n_per_out = 0;
1217 		adapter->ptp_caps.pps = 0;
1218 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_82599;
1219 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1220 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1221 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1222 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1223 		break;
1224 	case ixgbe_mac_X550:
1225 	case ixgbe_mac_X550EM_x:
1226 		snprintf(adapter->ptp_caps.name, 16, "%s", netdev->name);
1227 		adapter->ptp_caps.owner = THIS_MODULE;
1228 		adapter->ptp_caps.max_adj = 30000000;
1229 		adapter->ptp_caps.n_alarm = 0;
1230 		adapter->ptp_caps.n_ext_ts = 0;
1231 		adapter->ptp_caps.n_per_out = 0;
1232 		adapter->ptp_caps.pps = 0;
1233 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_X550;
1234 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1235 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1236 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1237 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1238 		adapter->ptp_setup_sdp = NULL;
1239 		break;
1240 	default:
1241 		adapter->ptp_clock = NULL;
1242 		adapter->ptp_setup_sdp = NULL;
1243 		return -EOPNOTSUPP;
1244 	}
1245 
1246 	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
1247 						&adapter->pdev->dev);
1248 	if (IS_ERR(adapter->ptp_clock)) {
1249 		err = PTR_ERR(adapter->ptp_clock);
1250 		adapter->ptp_clock = NULL;
1251 		e_dev_err("ptp_clock_register failed\n");
1252 		return err;
1253 	} else
1254 		e_dev_info("registered PHC device on %s\n", netdev->name);
1255 
1256 	/* set default timestamp mode to disabled here. We do this in
1257 	 * create_clock instead of init, because we don't want to override the
1258 	 * previous settings during a resume cycle.
1259 	 */
1260 	adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
1261 	adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
1262 
1263 	return 0;
1264 }
1265 
1266 /**
1267  * ixgbe_ptp_init
1268  * @adapter: the ixgbe private adapter structure
1269  *
1270  * This function performs the required steps for enabling PTP
1271  * support. If PTP support has already been loaded it simply calls the
1272  * cyclecounter init routine and exits.
1273  */
1274 void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
1275 {
1276 	/* initialize the spin lock first since we can't control when a user
1277 	 * will call the entry functions once we have initialized the clock
1278 	 * device
1279 	 */
1280 	spin_lock_init(&adapter->tmreg_lock);
1281 
1282 	/* obtain a PTP device, or re-use an existing device */
1283 	if (ixgbe_ptp_create_clock(adapter))
1284 		return;
1285 
1286 	/* we have a clock so we can initialize work now */
1287 	INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);
1288 
1289 	/* reset the PTP related hardware bits */
1290 	ixgbe_ptp_reset(adapter);
1291 
1292 	/* enter the IXGBE_PTP_RUNNING state */
1293 	set_bit(__IXGBE_PTP_RUNNING, &adapter->state);
1294 
1295 	return;
1296 }
1297 
1298 /**
1299  * ixgbe_ptp_suspend - stop PTP work items
1300  * @ adapter: pointer to adapter struct
1301  *
1302  * this function suspends PTP activity, and prevents more PTP work from being
1303  * generated, but does not destroy the PTP clock device.
1304  */
1305 void ixgbe_ptp_suspend(struct ixgbe_adapter *adapter)
1306 {
1307 	/* Leave the IXGBE_PTP_RUNNING state. */
1308 	if (!test_and_clear_bit(__IXGBE_PTP_RUNNING, &adapter->state))
1309 		return;
1310 
1311 	adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
1312 	if (adapter->ptp_setup_sdp)
1313 		adapter->ptp_setup_sdp(adapter);
1314 
1315 	/* ensure that we cancel any pending PTP Tx work item in progress */
1316 	cancel_work_sync(&adapter->ptp_tx_work);
1317 	ixgbe_ptp_clear_tx_timestamp(adapter);
1318 }
1319 
1320 /**
1321  * ixgbe_ptp_stop - close the PTP device
1322  * @adapter: pointer to adapter struct
1323  *
1324  * completely destroy the PTP device, should only be called when the device is
1325  * being fully closed.
1326  */
1327 void ixgbe_ptp_stop(struct ixgbe_adapter *adapter)
1328 {
1329 	/* first, suspend PTP activity */
1330 	ixgbe_ptp_suspend(adapter);
1331 
1332 	/* disable the PTP clock device */
1333 	if (adapter->ptp_clock) {
1334 		ptp_clock_unregister(adapter->ptp_clock);
1335 		adapter->ptp_clock = NULL;
1336 		e_dev_info("removed PHC on %s\n",
1337 			   adapter->netdev->name);
1338 	}
1339 }
1340