1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 2013 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/export.h>
30 #include <linux/ptp_classify.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 #define IXGBE_MAX_TIMEADJ_VALUE  0x7FFFFFFFFFFFFFFFULL
98 
99 #define IXGBE_OVERFLOW_PERIOD    (HZ * 30)
100 #define IXGBE_PTP_TX_TIMEOUT     (HZ * 15)
101 
102 #ifndef NSECS_PER_SEC
103 #define NSECS_PER_SEC 1000000000ULL
104 #endif
105 
106 /**
107  * ixgbe_ptp_setup_sdp
108  * @hw: the hardware private structure
109  *
110  * this function enables or disables the clock out feature on SDP0 for
111  * the X540 device. It will create a 1second periodic output that can
112  * be used as the PPS (via an interrupt).
113  *
114  * It calculates when the systime will be on an exact second, and then
115  * aligns the start of the PPS signal to that value. The shift is
116  * necessary because it can change based on the link speed.
117  */
118 static void ixgbe_ptp_setup_sdp(struct ixgbe_adapter *adapter)
119 {
120 	struct ixgbe_hw *hw = &adapter->hw;
121 	int shift = adapter->cc.shift;
122 	u32 esdp, tsauxc, clktiml, clktimh, trgttiml, trgttimh, rem;
123 	u64 ns = 0, clock_edge = 0;
124 
125 	if ((adapter->flags2 & IXGBE_FLAG2_PTP_PPS_ENABLED) &&
126 	    (hw->mac.type == ixgbe_mac_X540)) {
127 
128 		/* disable the pin first */
129 		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
130 		IXGBE_WRITE_FLUSH(hw);
131 
132 		esdp = IXGBE_READ_REG(hw, IXGBE_ESDP);
133 
134 		/*
135 		 * enable the SDP0 pin as output, and connected to the
136 		 * native function for Timesync (ClockOut)
137 		 */
138 		esdp |= (IXGBE_ESDP_SDP0_DIR |
139 			 IXGBE_ESDP_SDP0_NATIVE);
140 
141 		/*
142 		 * enable the Clock Out feature on SDP0, and allow
143 		 * interrupts to occur when the pin changes
144 		 */
145 		tsauxc = (IXGBE_TSAUXC_EN_CLK |
146 			  IXGBE_TSAUXC_SYNCLK |
147 			  IXGBE_TSAUXC_SDP0_INT);
148 
149 		/* clock period (or pulse length) */
150 		clktiml = (u32)(NSECS_PER_SEC << shift);
151 		clktimh = (u32)((NSECS_PER_SEC << shift) >> 32);
152 
153 		/*
154 		 * Account for the cyclecounter wrap-around value by
155 		 * using the converted ns value of the current time to
156 		 * check for when the next aligned second would occur.
157 		 */
158 		clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
159 		clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
160 		ns = timecounter_cyc2time(&adapter->tc, clock_edge);
161 
162 		div_u64_rem(ns, NSECS_PER_SEC, &rem);
163 		clock_edge += ((NSECS_PER_SEC - (u64)rem) << shift);
164 
165 		/* specify the initial clock start time */
166 		trgttiml = (u32)clock_edge;
167 		trgttimh = (u32)(clock_edge >> 32);
168 
169 		IXGBE_WRITE_REG(hw, IXGBE_CLKTIML, clktiml);
170 		IXGBE_WRITE_REG(hw, IXGBE_CLKTIMH, clktimh);
171 		IXGBE_WRITE_REG(hw, IXGBE_TRGTTIML0, trgttiml);
172 		IXGBE_WRITE_REG(hw, IXGBE_TRGTTIMH0, trgttimh);
173 
174 		IXGBE_WRITE_REG(hw, IXGBE_ESDP, esdp);
175 		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, tsauxc);
176 	} else {
177 		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
178 	}
179 
180 	IXGBE_WRITE_FLUSH(hw);
181 }
182 
183 /**
184  * ixgbe_ptp_read - read raw cycle counter (to be used by time counter)
185  * @cc: the cyclecounter structure
186  *
187  * this function reads the cyclecounter registers and is called by the
188  * cyclecounter structure used to construct a ns counter from the
189  * arbitrary fixed point registers
190  */
191 static cycle_t ixgbe_ptp_read(const struct cyclecounter *cc)
192 {
193 	struct ixgbe_adapter *adapter =
194 		container_of(cc, struct ixgbe_adapter, cc);
195 	struct ixgbe_hw *hw = &adapter->hw;
196 	u64 stamp = 0;
197 
198 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
199 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
200 
201 	return stamp;
202 }
203 
204 /**
205  * ixgbe_ptp_adjfreq
206  * @ptp: the ptp clock structure
207  * @ppb: parts per billion adjustment from base
208  *
209  * adjust the frequency of the ptp cycle counter by the
210  * indicated ppb from the base frequency.
211  */
212 static int ixgbe_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
213 {
214 	struct ixgbe_adapter *adapter =
215 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
216 	struct ixgbe_hw *hw = &adapter->hw;
217 	u64 freq;
218 	u32 diff, incval;
219 	int neg_adj = 0;
220 
221 	if (ppb < 0) {
222 		neg_adj = 1;
223 		ppb = -ppb;
224 	}
225 
226 	smp_mb();
227 	incval = ACCESS_ONCE(adapter->base_incval);
228 
229 	freq = incval;
230 	freq *= ppb;
231 	diff = div_u64(freq, 1000000000ULL);
232 
233 	incval = neg_adj ? (incval - diff) : (incval + diff);
234 
235 	switch (hw->mac.type) {
236 	case ixgbe_mac_X540:
237 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
238 		break;
239 	case ixgbe_mac_82599EB:
240 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
241 				(1 << IXGBE_INCPER_SHIFT_82599) |
242 				incval);
243 		break;
244 	default:
245 		break;
246 	}
247 
248 	return 0;
249 }
250 
251 /**
252  * ixgbe_ptp_adjtime
253  * @ptp: the ptp clock structure
254  * @delta: offset to adjust the cycle counter by
255  *
256  * adjust the timer by resetting the timecounter structure.
257  */
258 static int ixgbe_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
259 {
260 	struct ixgbe_adapter *adapter =
261 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
262 	unsigned long flags;
263 	u64 now;
264 
265 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
266 
267 	now = timecounter_read(&adapter->tc);
268 	now += delta;
269 
270 	/* reset the timecounter */
271 	timecounter_init(&adapter->tc,
272 			 &adapter->cc,
273 			 now);
274 
275 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
276 
277 	ixgbe_ptp_setup_sdp(adapter);
278 
279 	return 0;
280 }
281 
282 /**
283  * ixgbe_ptp_gettime
284  * @ptp: the ptp clock structure
285  * @ts: timespec structure to hold the current time value
286  *
287  * read the timecounter and return the correct value on ns,
288  * after converting it into a struct timespec.
289  */
290 static int ixgbe_ptp_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
291 {
292 	struct ixgbe_adapter *adapter =
293 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
294 	u64 ns;
295 	u32 remainder;
296 	unsigned long flags;
297 
298 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
299 	ns = timecounter_read(&adapter->tc);
300 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
301 
302 	ts->tv_sec = div_u64_rem(ns, 1000000000ULL, &remainder);
303 	ts->tv_nsec = remainder;
304 
305 	return 0;
306 }
307 
308 /**
309  * ixgbe_ptp_settime
310  * @ptp: the ptp clock structure
311  * @ts: the timespec containing the new time for the cycle counter
312  *
313  * reset the timecounter to use a new base value instead of the kernel
314  * wall timer value.
315  */
316 static int ixgbe_ptp_settime(struct ptp_clock_info *ptp,
317 			     const struct timespec *ts)
318 {
319 	struct ixgbe_adapter *adapter =
320 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
321 	u64 ns;
322 	unsigned long flags;
323 
324 	ns = ts->tv_sec * 1000000000ULL;
325 	ns += ts->tv_nsec;
326 
327 	/* reset the timecounter */
328 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
329 	timecounter_init(&adapter->tc, &adapter->cc, ns);
330 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
331 
332 	ixgbe_ptp_setup_sdp(adapter);
333 	return 0;
334 }
335 
336 /**
337  * ixgbe_ptp_enable
338  * @ptp: the ptp clock structure
339  * @rq: the requested feature to change
340  * @on: whether to enable or disable the feature
341  *
342  * enable (or disable) ancillary features of the phc subsystem.
343  * our driver only supports the PPS feature on the X540
344  */
345 static int ixgbe_ptp_enable(struct ptp_clock_info *ptp,
346 			    struct ptp_clock_request *rq, int on)
347 {
348 	struct ixgbe_adapter *adapter =
349 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
350 
351 	/**
352 	 * When PPS is enabled, unmask the interrupt for the ClockOut
353 	 * feature, so that the interrupt handler can send the PPS
354 	 * event when the clock SDP triggers. Clear mask when PPS is
355 	 * disabled
356 	 */
357 	if (rq->type == PTP_CLK_REQ_PPS) {
358 		switch (adapter->hw.mac.type) {
359 		case ixgbe_mac_X540:
360 			if (on)
361 				adapter->flags2 |= IXGBE_FLAG2_PTP_PPS_ENABLED;
362 			else
363 				adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
364 
365 			ixgbe_ptp_setup_sdp(adapter);
366 			return 0;
367 		default:
368 			break;
369 		}
370 	}
371 
372 	return -ENOTSUPP;
373 }
374 
375 /**
376  * ixgbe_ptp_check_pps_event
377  * @adapter: the private adapter structure
378  * @eicr: the interrupt cause register value
379  *
380  * This function is called by the interrupt routine when checking for
381  * interrupts. It will check and handle a pps event.
382  */
383 void ixgbe_ptp_check_pps_event(struct ixgbe_adapter *adapter, u32 eicr)
384 {
385 	struct ixgbe_hw *hw = &adapter->hw;
386 	struct ptp_clock_event event;
387 
388 	event.type = PTP_CLOCK_PPS;
389 
390 	/* this check is necessary in case the interrupt was enabled via some
391 	 * alternative means (ex. debug_fs). Better to check here than
392 	 * everywhere that calls this function.
393 	 */
394 	if (!adapter->ptp_clock)
395 		return;
396 
397 	switch (hw->mac.type) {
398 	case ixgbe_mac_X540:
399 		ptp_clock_event(adapter->ptp_clock, &event);
400 		break;
401 	default:
402 		break;
403 	}
404 }
405 
406 /**
407  * ixgbe_ptp_overflow_check - watchdog task to detect SYSTIME overflow
408  * @adapter: private adapter struct
409  *
410  * this watchdog task periodically reads the timecounter
411  * in order to prevent missing when the system time registers wrap
412  * around. This needs to be run approximately twice a minute.
413  */
414 void ixgbe_ptp_overflow_check(struct ixgbe_adapter *adapter)
415 {
416 	bool timeout = time_is_before_jiffies(adapter->last_overflow_check +
417 					     IXGBE_OVERFLOW_PERIOD);
418 	struct timespec ts;
419 
420 	if (timeout) {
421 		ixgbe_ptp_gettime(&adapter->ptp_caps, &ts);
422 		adapter->last_overflow_check = jiffies;
423 	}
424 }
425 
426 /**
427  * ixgbe_ptp_rx_hang - detect error case when Rx timestamp registers latched
428  * @adapter: private network adapter structure
429  *
430  * this watchdog task is scheduled to detect error case where hardware has
431  * dropped an Rx packet that was timestamped when the ring is full. The
432  * particular error is rare but leaves the device in a state unable to timestamp
433  * any future packets.
434  */
435 void ixgbe_ptp_rx_hang(struct ixgbe_adapter *adapter)
436 {
437 	struct ixgbe_hw *hw = &adapter->hw;
438 	struct ixgbe_ring *rx_ring;
439 	u32 tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
440 	unsigned long rx_event;
441 	int n;
442 
443 	/* if we don't have a valid timestamp in the registers, just update the
444 	 * timeout counter and exit
445 	 */
446 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID)) {
447 		adapter->last_rx_ptp_check = jiffies;
448 		return;
449 	}
450 
451 	/* determine the most recent watchdog or rx_timestamp event */
452 	rx_event = adapter->last_rx_ptp_check;
453 	for (n = 0; n < adapter->num_rx_queues; n++) {
454 		rx_ring = adapter->rx_ring[n];
455 		if (time_after(rx_ring->last_rx_timestamp, rx_event))
456 			rx_event = rx_ring->last_rx_timestamp;
457 	}
458 
459 	/* only need to read the high RXSTMP register to clear the lock */
460 	if (time_is_before_jiffies(rx_event + 5*HZ)) {
461 		IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
462 		adapter->last_rx_ptp_check = jiffies;
463 
464 		e_warn(drv, "clearing RX Timestamp hang");
465 	}
466 }
467 
468 /**
469  * ixgbe_ptp_tx_hwtstamp - utility function which checks for TX time stamp
470  * @adapter: the private adapter struct
471  *
472  * if the timestamp is valid, we convert it into the timecounter ns
473  * value, then store that result into the shhwtstamps structure which
474  * is passed up the network stack
475  */
476 static void ixgbe_ptp_tx_hwtstamp(struct ixgbe_adapter *adapter)
477 {
478 	struct ixgbe_hw *hw = &adapter->hw;
479 	struct skb_shared_hwtstamps shhwtstamps;
480 	u64 regval = 0, ns;
481 	unsigned long flags;
482 
483 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPL);
484 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPH) << 32;
485 
486 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
487 	ns = timecounter_cyc2time(&adapter->tc, regval);
488 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
489 
490 	memset(&shhwtstamps, 0, sizeof(shhwtstamps));
491 	shhwtstamps.hwtstamp = ns_to_ktime(ns);
492 	skb_tstamp_tx(adapter->ptp_tx_skb, &shhwtstamps);
493 
494 	dev_kfree_skb_any(adapter->ptp_tx_skb);
495 	adapter->ptp_tx_skb = NULL;
496 	clear_bit_unlock(__IXGBE_PTP_TX_IN_PROGRESS, &adapter->state);
497 }
498 
499 /**
500  * ixgbe_ptp_tx_hwtstamp_work
501  * @work: pointer to the work struct
502  *
503  * This work item polls TSYNCTXCTL valid bit to determine when a Tx hardware
504  * timestamp has been taken for the current skb. It is necesary, because the
505  * descriptor's "done" bit does not correlate with the timestamp event.
506  */
507 static void ixgbe_ptp_tx_hwtstamp_work(struct work_struct *work)
508 {
509 	struct ixgbe_adapter *adapter = container_of(work, struct ixgbe_adapter,
510 						     ptp_tx_work);
511 	struct ixgbe_hw *hw = &adapter->hw;
512 	bool timeout = time_is_before_jiffies(adapter->ptp_tx_start +
513 					      IXGBE_PTP_TX_TIMEOUT);
514 	u32 tsynctxctl;
515 
516 	if (timeout) {
517 		dev_kfree_skb_any(adapter->ptp_tx_skb);
518 		adapter->ptp_tx_skb = NULL;
519 		clear_bit_unlock(__IXGBE_PTP_TX_IN_PROGRESS, &adapter->state);
520 		e_warn(drv, "clearing Tx Timestamp hang");
521 		return;
522 	}
523 
524 	tsynctxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
525 	if (tsynctxctl & IXGBE_TSYNCTXCTL_VALID)
526 		ixgbe_ptp_tx_hwtstamp(adapter);
527 	else
528 		/* reschedule to keep checking if it's not available yet */
529 		schedule_work(&adapter->ptp_tx_work);
530 }
531 
532 /**
533  * __ixgbe_ptp_rx_hwtstamp - utility function which checks for RX time stamp
534  * @q_vector: structure containing interrupt and ring information
535  * @skb: particular skb to send timestamp with
536  *
537  * if the timestamp is valid, we convert it into the timecounter ns
538  * value, then store that result into the shhwtstamps structure which
539  * is passed up the network stack
540  */
541 void __ixgbe_ptp_rx_hwtstamp(struct ixgbe_q_vector *q_vector,
542 			     struct sk_buff *skb)
543 {
544 	struct ixgbe_adapter *adapter;
545 	struct ixgbe_hw *hw;
546 	struct skb_shared_hwtstamps *shhwtstamps;
547 	u64 regval = 0, ns;
548 	u32 tsyncrxctl;
549 	unsigned long flags;
550 
551 	/* we cannot process timestamps on a ring without a q_vector */
552 	if (!q_vector || !q_vector->adapter)
553 		return;
554 
555 	adapter = q_vector->adapter;
556 	hw = &adapter->hw;
557 
558 	/*
559 	 * Read the tsyncrxctl register afterwards in order to prevent taking an
560 	 * I/O hit on every packet.
561 	 */
562 	tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
563 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID))
564 		return;
565 
566 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPL);
567 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPH) << 32;
568 
569 
570 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
571 	ns = timecounter_cyc2time(&adapter->tc, regval);
572 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
573 
574 	shhwtstamps = skb_hwtstamps(skb);
575 	shhwtstamps->hwtstamp = ns_to_ktime(ns);
576 }
577 
578 int ixgbe_ptp_get_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
579 {
580 	struct hwtstamp_config *config = &adapter->tstamp_config;
581 
582 	return copy_to_user(ifr->ifr_data, config,
583 			    sizeof(*config)) ? -EFAULT : 0;
584 }
585 
586 /**
587  * ixgbe_ptp_set_ts_config - control hardware time stamping
588  * @adapter: pointer to adapter struct
589  * @ifreq: ioctl data
590  *
591  * Outgoing time stamping can be enabled and disabled. Play nice and
592  * disable it when requested, although it shouldn't cause any overhead
593  * when no packet needs it. At most one packet in the queue may be
594  * marked for time stamping, otherwise it would be impossible to tell
595  * for sure to which packet the hardware time stamp belongs.
596  *
597  * Incoming time stamping has to be configured via the hardware
598  * filters. Not all combinations are supported, in particular event
599  * type has to be specified. Matching the kind of event packet is
600  * not supported, with the exception of "all V2 events regardless of
601  * level 2 or 4".
602  *
603  * Since hardware always timestamps Path delay packets when timestamping V2
604  * packets, regardless of the type specified in the register, only use V2
605  * Event mode. This more accurately tells the user what the hardware is going
606  * to do anyways.
607  */
608 int ixgbe_ptp_set_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
609 {
610 	struct ixgbe_hw *hw = &adapter->hw;
611 	struct hwtstamp_config config;
612 	u32 tsync_tx_ctl = IXGBE_TSYNCTXCTL_ENABLED;
613 	u32 tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED;
614 	u32 tsync_rx_mtrl = PTP_EV_PORT << 16;
615 	bool is_l2 = false;
616 	u32 regval;
617 
618 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
619 		return -EFAULT;
620 
621 	/* reserved for future extensions */
622 	if (config.flags)
623 		return -EINVAL;
624 
625 	switch (config.tx_type) {
626 	case HWTSTAMP_TX_OFF:
627 		tsync_tx_ctl = 0;
628 	case HWTSTAMP_TX_ON:
629 		break;
630 	default:
631 		return -ERANGE;
632 	}
633 
634 	switch (config.rx_filter) {
635 	case HWTSTAMP_FILTER_NONE:
636 		tsync_rx_ctl = 0;
637 		tsync_rx_mtrl = 0;
638 		break;
639 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
640 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
641 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_SYNC_MSG;
642 		break;
643 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
644 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
645 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_DELAY_REQ_MSG;
646 		break;
647 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
648 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
649 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
650 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
651 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
652 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
653 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
654 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
655 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
656 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_EVENT_V2;
657 		is_l2 = true;
658 		config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
659 		break;
660 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
661 	case HWTSTAMP_FILTER_ALL:
662 	default:
663 		/*
664 		 * register RXMTRL must be set in order to do V1 packets,
665 		 * therefore it is not possible to time stamp both V1 Sync and
666 		 * Delay_Req messages and hardware does not support
667 		 * timestamping all packets => return error
668 		 */
669 		config.rx_filter = HWTSTAMP_FILTER_NONE;
670 		return -ERANGE;
671 	}
672 
673 	if (hw->mac.type == ixgbe_mac_82598EB) {
674 		if (tsync_rx_ctl | tsync_tx_ctl)
675 			return -ERANGE;
676 		return 0;
677 	}
678 
679 	/* define ethertype filter for timestamping L2 packets */
680 	if (is_l2)
681 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
682 				(IXGBE_ETQF_FILTER_EN | /* enable filter */
683 				 IXGBE_ETQF_1588 | /* enable timestamping */
684 				 ETH_P_1588));     /* 1588 eth protocol type */
685 	else
686 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588), 0);
687 
688 
689 	/* enable/disable TX */
690 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
691 	regval &= ~IXGBE_TSYNCTXCTL_ENABLED;
692 	regval |= tsync_tx_ctl;
693 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCTXCTL, regval);
694 
695 	/* enable/disable RX */
696 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
697 	regval &= ~(IXGBE_TSYNCRXCTL_ENABLED | IXGBE_TSYNCRXCTL_TYPE_MASK);
698 	regval |= tsync_rx_ctl;
699 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, regval);
700 
701 	/* define which PTP packets are time stamped */
702 	IXGBE_WRITE_REG(hw, IXGBE_RXMTRL, tsync_rx_mtrl);
703 
704 	IXGBE_WRITE_FLUSH(hw);
705 
706 	/* clear TX/RX time stamp registers, just to be sure */
707 	regval = IXGBE_READ_REG(hw, IXGBE_TXSTMPH);
708 	regval = IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
709 
710 	/* save these settings for future reference */
711 	memcpy(&adapter->tstamp_config, &config,
712 	       sizeof(adapter->tstamp_config));
713 
714 	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
715 		-EFAULT : 0;
716 }
717 
718 /**
719  * ixgbe_ptp_start_cyclecounter - create the cycle counter from hw
720  * @adapter: pointer to the adapter structure
721  *
722  * This function should be called to set the proper values for the TIMINCA
723  * register and tell the cyclecounter structure what the tick rate of SYSTIME
724  * is. It does not directly modify SYSTIME registers or the timecounter
725  * structure. It should be called whenever a new TIMINCA value is necessary,
726  * such as during initialization or when the link speed changes.
727  */
728 void ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter *adapter)
729 {
730 	struct ixgbe_hw *hw = &adapter->hw;
731 	u32 incval = 0;
732 	u32 shift = 0;
733 	unsigned long flags;
734 
735 	/**
736 	 * Scale the NIC cycle counter by a large factor so that
737 	 * relatively small corrections to the frequency can be added
738 	 * or subtracted. The drawbacks of a large factor include
739 	 * (a) the clock register overflows more quickly, (b) the cycle
740 	 * counter structure must be able to convert the systime value
741 	 * to nanoseconds using only a multiplier and a right-shift,
742 	 * and (c) the value must fit within the timinca register space
743 	 * => math based on internal DMA clock rate and available bits
744 	 *
745 	 * Note that when there is no link, internal DMA clock is same as when
746 	 * link speed is 10Gb. Set the registers correctly even when link is
747 	 * down to preserve the clock setting
748 	 */
749 	switch (adapter->link_speed) {
750 	case IXGBE_LINK_SPEED_100_FULL:
751 		incval = IXGBE_INCVAL_100;
752 		shift = IXGBE_INCVAL_SHIFT_100;
753 		break;
754 	case IXGBE_LINK_SPEED_1GB_FULL:
755 		incval = IXGBE_INCVAL_1GB;
756 		shift = IXGBE_INCVAL_SHIFT_1GB;
757 		break;
758 	case IXGBE_LINK_SPEED_10GB_FULL:
759 	default:
760 		incval = IXGBE_INCVAL_10GB;
761 		shift = IXGBE_INCVAL_SHIFT_10GB;
762 		break;
763 	}
764 
765 	/**
766 	 * Modify the calculated values to fit within the correct
767 	 * number of bits specified by the hardware. The 82599 doesn't
768 	 * have the same space as the X540, so bitshift the calculated
769 	 * values to fit.
770 	 */
771 	switch (hw->mac.type) {
772 	case ixgbe_mac_X540:
773 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
774 		break;
775 	case ixgbe_mac_82599EB:
776 		incval >>= IXGBE_INCVAL_SHIFT_82599;
777 		shift -= IXGBE_INCVAL_SHIFT_82599;
778 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
779 				(1 << IXGBE_INCPER_SHIFT_82599) |
780 				incval);
781 		break;
782 	default:
783 		/* other devices aren't supported */
784 		return;
785 	}
786 
787 	/* update the base incval used to calculate frequency adjustment */
788 	ACCESS_ONCE(adapter->base_incval) = incval;
789 	smp_mb();
790 
791 	/* need lock to prevent incorrect read while modifying cyclecounter */
792 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
793 
794 	memset(&adapter->cc, 0, sizeof(adapter->cc));
795 	adapter->cc.read = ixgbe_ptp_read;
796 	adapter->cc.mask = CLOCKSOURCE_MASK(64);
797 	adapter->cc.shift = shift;
798 	adapter->cc.mult = 1;
799 
800 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
801 }
802 
803 /**
804  * ixgbe_ptp_reset
805  * @adapter: the ixgbe private board structure
806  *
807  * When the MAC resets, all timesync features are reset. This function should be
808  * called to re-enable the PTP clock structure. It will re-init the timecounter
809  * structure based on the kernel time as well as setup the cycle counter data.
810  */
811 void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
812 {
813 	struct ixgbe_hw *hw = &adapter->hw;
814 	unsigned long flags;
815 
816 	/* set SYSTIME registers to 0 just in case */
817 	IXGBE_WRITE_REG(hw, IXGBE_SYSTIML, 0x00000000);
818 	IXGBE_WRITE_REG(hw, IXGBE_SYSTIMH, 0x00000000);
819 	IXGBE_WRITE_FLUSH(hw);
820 
821 	/* Reset the saved tstamp_config */
822 	memset(&adapter->tstamp_config, 0, sizeof(adapter->tstamp_config));
823 
824 	ixgbe_ptp_start_cyclecounter(adapter);
825 
826 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
827 
828 	/* reset the ns time counter */
829 	timecounter_init(&adapter->tc, &adapter->cc,
830 			 ktime_to_ns(ktime_get_real()));
831 
832 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
833 
834 	/*
835 	 * Now that the shift has been calculated and the systime
836 	 * registers reset, (re-)enable the Clock out feature
837 	 */
838 	ixgbe_ptp_setup_sdp(adapter);
839 }
840 
841 /**
842  * ixgbe_ptp_init
843  * @adapter: the ixgbe private adapter structure
844  *
845  * This function performs the required steps for enabling ptp
846  * support. If ptp support has already been loaded it simply calls the
847  * cyclecounter init routine and exits.
848  */
849 void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
850 {
851 	struct net_device *netdev = adapter->netdev;
852 
853 	switch (adapter->hw.mac.type) {
854 	case ixgbe_mac_X540:
855 		snprintf(adapter->ptp_caps.name,
856 			 sizeof(adapter->ptp_caps.name),
857 			 "%s", netdev->name);
858 		adapter->ptp_caps.owner = THIS_MODULE;
859 		adapter->ptp_caps.max_adj = 250000000;
860 		adapter->ptp_caps.n_alarm = 0;
861 		adapter->ptp_caps.n_ext_ts = 0;
862 		adapter->ptp_caps.n_per_out = 0;
863 		adapter->ptp_caps.pps = 1;
864 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq;
865 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
866 		adapter->ptp_caps.gettime = ixgbe_ptp_gettime;
867 		adapter->ptp_caps.settime = ixgbe_ptp_settime;
868 		adapter->ptp_caps.enable = ixgbe_ptp_enable;
869 		break;
870 	case ixgbe_mac_82599EB:
871 		snprintf(adapter->ptp_caps.name,
872 			 sizeof(adapter->ptp_caps.name),
873 			 "%s", netdev->name);
874 		adapter->ptp_caps.owner = THIS_MODULE;
875 		adapter->ptp_caps.max_adj = 250000000;
876 		adapter->ptp_caps.n_alarm = 0;
877 		adapter->ptp_caps.n_ext_ts = 0;
878 		adapter->ptp_caps.n_per_out = 0;
879 		adapter->ptp_caps.pps = 0;
880 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq;
881 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
882 		adapter->ptp_caps.gettime = ixgbe_ptp_gettime;
883 		adapter->ptp_caps.settime = ixgbe_ptp_settime;
884 		adapter->ptp_caps.enable = ixgbe_ptp_enable;
885 		break;
886 	default:
887 		adapter->ptp_clock = NULL;
888 		return;
889 	}
890 
891 	spin_lock_init(&adapter->tmreg_lock);
892 	INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);
893 
894 	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
895 						&adapter->pdev->dev);
896 	if (IS_ERR(adapter->ptp_clock)) {
897 		adapter->ptp_clock = NULL;
898 		e_dev_err("ptp_clock_register failed\n");
899 	} else
900 		e_dev_info("registered PHC device on %s\n", netdev->name);
901 
902 	ixgbe_ptp_reset(adapter);
903 
904 	/* enter the IXGBE_PTP_RUNNING state */
905 	set_bit(__IXGBE_PTP_RUNNING, &adapter->state);
906 
907 	return;
908 }
909 
910 /**
911  * ixgbe_ptp_stop - disable ptp device and stop the overflow check
912  * @adapter: pointer to adapter struct
913  *
914  * this function stops the ptp support, and cancels the delayed work.
915  */
916 void ixgbe_ptp_stop(struct ixgbe_adapter *adapter)
917 {
918 	/* Leave the IXGBE_PTP_RUNNING state. */
919 	if (!test_and_clear_bit(__IXGBE_PTP_RUNNING, &adapter->state))
920 		return;
921 
922 	/* stop the PPS signal */
923 	adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
924 	ixgbe_ptp_setup_sdp(adapter);
925 
926 	cancel_work_sync(&adapter->ptp_tx_work);
927 	if (adapter->ptp_tx_skb) {
928 		dev_kfree_skb_any(adapter->ptp_tx_skb);
929 		adapter->ptp_tx_skb = NULL;
930 		clear_bit_unlock(__IXGBE_PTP_TX_IN_PROGRESS, &adapter->state);
931 	}
932 
933 	if (adapter->ptp_clock) {
934 		ptp_clock_unregister(adapter->ptp_clock);
935 		adapter->ptp_clock = NULL;
936 		e_dev_info("removed PHC on %s\n",
937 			   adapter->netdev->name);
938 	}
939 }
940