1 /*******************************************************************************
2  *
3  * Intel Ethernet Controller XL710 Family Linux Driver
4  * Copyright(c) 2013 - 2014 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
16  * with this program.  If not, see <http://www.gnu.org/licenses/>.
17  *
18  * The full GNU General Public License is included in this distribution in
19  * the file called "COPYING".
20  *
21  * Contact Information:
22  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  ******************************************************************************/
26 
27 #include "i40e.h"
28 #include <linux/ptp_classify.h>
29 
30 /* The XL710 timesync is very much like Intel's 82599 design when it comes to
31  * the fundamental clock design. However, the clock operations are much simpler
32  * in the XL710 because the device supports a full 64 bits of nanoseconds.
33  * Because the field is so wide, we can forgo the cycle counter and just
34  * operate with the nanosecond field directly without fear of overflow.
35  *
36  * Much like the 82599, the update period is dependent upon the link speed:
37  * At 40Gb link or no link, the period is 1.6ns.
38  * At 10Gb link, the period is multiplied by 2. (3.2ns)
39  * At 1Gb link, the period is multiplied by 20. (32ns)
40  * 1588 functionality is not supported at 100Mbps.
41  */
42 #define I40E_PTP_40GB_INCVAL 0x0199999999ULL
43 #define I40E_PTP_10GB_INCVAL 0x0333333333ULL
44 #define I40E_PTP_1GB_INCVAL  0x2000000000ULL
45 
46 #define I40E_PRTTSYN_CTL1_TSYNTYPE_V1  (0x1 << \
47 					I40E_PRTTSYN_CTL1_TSYNTYPE_SHIFT)
48 #define I40E_PRTTSYN_CTL1_TSYNTYPE_V2  (0x2 << \
49 					I40E_PRTTSYN_CTL1_TSYNTYPE_SHIFT)
50 
51 /**
52  * i40e_ptp_read - Read the PHC time from the device
53  * @pf: Board private structure
54  * @ts: timespec structure to hold the current time value
55  *
56  * This function reads the PRTTSYN_TIME registers and stores them in a
57  * timespec. However, since the registers are 64 bits of nanoseconds, we must
58  * convert the result to a timespec before we can return.
59  **/
60 static void i40e_ptp_read(struct i40e_pf *pf, struct timespec *ts)
61 {
62 	struct i40e_hw *hw = &pf->hw;
63 	u32 hi, lo;
64 	u64 ns;
65 
66 	/* The timer latches on the lowest register read. */
67 	lo = rd32(hw, I40E_PRTTSYN_TIME_L);
68 	hi = rd32(hw, I40E_PRTTSYN_TIME_H);
69 
70 	ns = (((u64)hi) << 32) | lo;
71 
72 	*ts = ns_to_timespec(ns);
73 }
74 
75 /**
76  * i40e_ptp_write - Write the PHC time to the device
77  * @pf: Board private structure
78  * @ts: timespec structure that holds the new time value
79  *
80  * This function writes the PRTTSYN_TIME registers with the user value. Since
81  * we receive a timespec from the stack, we must convert that timespec into
82  * nanoseconds before programming the registers.
83  **/
84 static void i40e_ptp_write(struct i40e_pf *pf, const struct timespec *ts)
85 {
86 	struct i40e_hw *hw = &pf->hw;
87 	u64 ns = timespec_to_ns(ts);
88 
89 	/* The timer will not update until the high register is written, so
90 	 * write the low register first.
91 	 */
92 	wr32(hw, I40E_PRTTSYN_TIME_L, ns & 0xFFFFFFFF);
93 	wr32(hw, I40E_PRTTSYN_TIME_H, ns >> 32);
94 }
95 
96 /**
97  * i40e_ptp_convert_to_hwtstamp - Convert device clock to system time
98  * @hwtstamps: Timestamp structure to update
99  * @timestamp: Timestamp from the hardware
100  *
101  * We need to convert the NIC clock value into a hwtstamp which can be used by
102  * the upper level timestamping functions. Since the timestamp is simply a 64-
103  * bit nanosecond value, we can call ns_to_ktime directly to handle this.
104  **/
105 static void i40e_ptp_convert_to_hwtstamp(struct skb_shared_hwtstamps *hwtstamps,
106 					 u64 timestamp)
107 {
108 	memset(hwtstamps, 0, sizeof(*hwtstamps));
109 
110 	hwtstamps->hwtstamp = ns_to_ktime(timestamp);
111 }
112 
113 /**
114  * i40e_ptp_adjfreq - Adjust the PHC frequency
115  * @ptp: The PTP clock structure
116  * @ppb: Parts per billion adjustment from the base
117  *
118  * Adjust the frequency of the PHC by the indicated parts per billion from the
119  * base frequency.
120  **/
121 static int i40e_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
122 {
123 	struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps);
124 	struct i40e_hw *hw = &pf->hw;
125 	u64 adj, freq, diff;
126 	int neg_adj = 0;
127 
128 	if (ppb < 0) {
129 		neg_adj = 1;
130 		ppb = -ppb;
131 	}
132 
133 	smp_mb(); /* Force any pending update before accessing. */
134 	adj = ACCESS_ONCE(pf->ptp_base_adj);
135 
136 	freq = adj;
137 	freq *= ppb;
138 	diff = div_u64(freq, 1000000000ULL);
139 
140 	if (neg_adj)
141 		adj -= diff;
142 	else
143 		adj += diff;
144 
145 	wr32(hw, I40E_PRTTSYN_INC_L, adj & 0xFFFFFFFF);
146 	wr32(hw, I40E_PRTTSYN_INC_H, adj >> 32);
147 
148 	return 0;
149 }
150 
151 /**
152  * i40e_ptp_adjtime - Adjust the PHC time
153  * @ptp: The PTP clock structure
154  * @delta: Offset in nanoseconds to adjust the PHC time by
155  *
156  * Adjust the frequency of the PHC by the indicated parts per billion from the
157  * base frequency.
158  **/
159 static int i40e_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
160 {
161 	struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps);
162 	struct timespec now, then = ns_to_timespec(delta);
163 	unsigned long flags;
164 
165 	spin_lock_irqsave(&pf->tmreg_lock, flags);
166 
167 	i40e_ptp_read(pf, &now);
168 	now = timespec_add(now, then);
169 	i40e_ptp_write(pf, (const struct timespec *)&now);
170 
171 	spin_unlock_irqrestore(&pf->tmreg_lock, flags);
172 
173 	return 0;
174 }
175 
176 /**
177  * i40e_ptp_gettime - Get the time of the PHC
178  * @ptp: The PTP clock structure
179  * @ts: timespec structure to hold the current time value
180  *
181  * Read the device clock and return the correct value on ns, after converting it
182  * into a timespec struct.
183  **/
184 static int i40e_ptp_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
185 {
186 	struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps);
187 	unsigned long flags;
188 
189 	spin_lock_irqsave(&pf->tmreg_lock, flags);
190 	i40e_ptp_read(pf, ts);
191 	spin_unlock_irqrestore(&pf->tmreg_lock, flags);
192 
193 	return 0;
194 }
195 
196 /**
197  * i40e_ptp_settime - Set the time of the PHC
198  * @ptp: The PTP clock structure
199  * @ts: timespec structure that holds the new time value
200  *
201  * Set the device clock to the user input value. The conversion from timespec
202  * to ns happens in the write function.
203  **/
204 static int i40e_ptp_settime(struct ptp_clock_info *ptp,
205 			    const struct timespec *ts)
206 {
207 	struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps);
208 	unsigned long flags;
209 
210 	spin_lock_irqsave(&pf->tmreg_lock, flags);
211 	i40e_ptp_write(pf, ts);
212 	spin_unlock_irqrestore(&pf->tmreg_lock, flags);
213 
214 	return 0;
215 }
216 
217 /**
218  * i40e_ptp_feature_enable - Enable/disable ancillary features of the PHC subsystem
219  * @ptp: The PTP clock structure
220  * @rq: The requested feature to change
221  * @on: Enable/disable flag
222  *
223  * The XL710 does not support any of the ancillary features of the PHC
224  * subsystem, so this function may just return.
225  **/
226 static int i40e_ptp_feature_enable(struct ptp_clock_info *ptp,
227 				   struct ptp_clock_request *rq, int on)
228 {
229 	return -EOPNOTSUPP;
230 }
231 
232 /**
233  * i40e_ptp_rx_hang - Detect error case when Rx timestamp registers are hung
234  * @vsi: The VSI with the rings relevant to 1588
235  *
236  * This watchdog task is scheduled to detect error case where hardware has
237  * dropped an Rx packet that was timestamped when the ring is full. The
238  * particular error is rare but leaves the device in a state unable to timestamp
239  * any future packets.
240  **/
241 void i40e_ptp_rx_hang(struct i40e_vsi *vsi)
242 {
243 	struct i40e_pf *pf = vsi->back;
244 	struct i40e_hw *hw = &pf->hw;
245 	struct i40e_ring *rx_ring;
246 	unsigned long rx_event;
247 	u32 prttsyn_stat;
248 	int n;
249 
250 	if (!(pf->flags & I40E_FLAG_PTP))
251 		return;
252 
253 	prttsyn_stat = rd32(hw, I40E_PRTTSYN_STAT_1);
254 
255 	/* Unless all four receive timestamp registers are latched, we are not
256 	 * concerned about a possible PTP Rx hang, so just update the timeout
257 	 * counter and exit.
258 	 */
259 	if (!(prttsyn_stat & ((I40E_PRTTSYN_STAT_1_RXT0_MASK <<
260 			       I40E_PRTTSYN_STAT_1_RXT0_SHIFT) |
261 			      (I40E_PRTTSYN_STAT_1_RXT1_MASK <<
262 			       I40E_PRTTSYN_STAT_1_RXT1_SHIFT) |
263 			      (I40E_PRTTSYN_STAT_1_RXT2_MASK <<
264 			       I40E_PRTTSYN_STAT_1_RXT2_SHIFT) |
265 			      (I40E_PRTTSYN_STAT_1_RXT3_MASK <<
266 			       I40E_PRTTSYN_STAT_1_RXT3_SHIFT)))) {
267 		pf->last_rx_ptp_check = jiffies;
268 		return;
269 	}
270 
271 	/* Determine the most recent watchdog or rx_timestamp event. */
272 	rx_event = pf->last_rx_ptp_check;
273 	for (n = 0; n < vsi->num_queue_pairs; n++) {
274 		rx_ring = vsi->rx_rings[n];
275 		if (time_after(rx_ring->last_rx_timestamp, rx_event))
276 			rx_event = rx_ring->last_rx_timestamp;
277 	}
278 
279 	/* Only need to read the high RXSTMP register to clear the lock */
280 	if (time_is_before_jiffies(rx_event + 5 * HZ)) {
281 		rd32(hw, I40E_PRTTSYN_RXTIME_H(0));
282 		rd32(hw, I40E_PRTTSYN_RXTIME_H(1));
283 		rd32(hw, I40E_PRTTSYN_RXTIME_H(2));
284 		rd32(hw, I40E_PRTTSYN_RXTIME_H(3));
285 		pf->last_rx_ptp_check = jiffies;
286 		pf->rx_hwtstamp_cleared++;
287 		dev_warn(&vsi->back->pdev->dev,
288 			 "%s: clearing Rx timestamp hang\n",
289 			 __func__);
290 	}
291 }
292 
293 /**
294  * i40e_ptp_tx_hwtstamp - Utility function which returns the Tx timestamp
295  * @pf: Board private structure
296  *
297  * Read the value of the Tx timestamp from the registers, convert it into a
298  * value consumable by the stack, and store that result into the shhwtstamps
299  * struct before returning it up the stack.
300  **/
301 void i40e_ptp_tx_hwtstamp(struct i40e_pf *pf)
302 {
303 	struct skb_shared_hwtstamps shhwtstamps;
304 	struct i40e_hw *hw = &pf->hw;
305 	u32 hi, lo;
306 	u64 ns;
307 
308 	lo = rd32(hw, I40E_PRTTSYN_TXTIME_L);
309 	hi = rd32(hw, I40E_PRTTSYN_TXTIME_H);
310 
311 	ns = (((u64)hi) << 32) | lo;
312 
313 	i40e_ptp_convert_to_hwtstamp(&shhwtstamps, ns);
314 	skb_tstamp_tx(pf->ptp_tx_skb, &shhwtstamps);
315 	dev_kfree_skb_any(pf->ptp_tx_skb);
316 	pf->ptp_tx_skb = NULL;
317 	clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, &pf->state);
318 }
319 
320 /**
321  * i40e_ptp_rx_hwtstamp - Utility function which checks for an Rx timestamp
322  * @pf: Board private structure
323  * @skb: Particular skb to send timestamp with
324  * @index: Index into the receive timestamp registers for the timestamp
325  *
326  * The XL710 receives a notification in the receive descriptor with an offset
327  * into the set of RXTIME registers where the timestamp is for that skb. This
328  * function goes and fetches the receive timestamp from that offset, if a valid
329  * one exists. The RXTIME registers are in ns, so we must convert the result
330  * first.
331  **/
332 void i40e_ptp_rx_hwtstamp(struct i40e_pf *pf, struct sk_buff *skb, u8 index)
333 {
334 	u32 prttsyn_stat, hi, lo;
335 	struct i40e_hw *hw;
336 	u64 ns;
337 
338 	/* Since we cannot turn off the Rx timestamp logic if the device is
339 	 * doing Tx timestamping, check if Rx timestamping is configured.
340 	 */
341 	if (!pf->ptp_rx)
342 		return;
343 
344 	hw = &pf->hw;
345 
346 	prttsyn_stat = rd32(hw, I40E_PRTTSYN_STAT_1);
347 
348 	if (!(prttsyn_stat & (1 << index)))
349 		return;
350 
351 	lo = rd32(hw, I40E_PRTTSYN_RXTIME_L(index));
352 	hi = rd32(hw, I40E_PRTTSYN_RXTIME_H(index));
353 
354 	ns = (((u64)hi) << 32) | lo;
355 
356 	i40e_ptp_convert_to_hwtstamp(skb_hwtstamps(skb), ns);
357 }
358 
359 /**
360  * i40e_ptp_set_increment - Utility function to update clock increment rate
361  * @pf: Board private structure
362  *
363  * During a link change, the DMA frequency that drives the 1588 logic will
364  * change. In order to keep the PRTTSYN_TIME registers in units of nanoseconds,
365  * we must update the increment value per clock tick.
366  **/
367 void i40e_ptp_set_increment(struct i40e_pf *pf)
368 {
369 	struct i40e_link_status *hw_link_info;
370 	struct i40e_hw *hw = &pf->hw;
371 	u64 incval;
372 
373 	hw_link_info = &hw->phy.link_info;
374 
375 	i40e_aq_get_link_info(&pf->hw, true, NULL, NULL);
376 
377 	switch (hw_link_info->link_speed) {
378 	case I40E_LINK_SPEED_10GB:
379 		incval = I40E_PTP_10GB_INCVAL;
380 		break;
381 	case I40E_LINK_SPEED_1GB:
382 		incval = I40E_PTP_1GB_INCVAL;
383 		break;
384 	case I40E_LINK_SPEED_100MB:
385 	{
386 		static int warn_once;
387 
388 		if (!warn_once) {
389 			dev_warn(&pf->pdev->dev,
390 				 "1588 functionality is not supported at 100 Mbps. Stopping the PHC.\n");
391 			warn_once++;
392 		}
393 		incval = 0;
394 		break;
395 	}
396 	case I40E_LINK_SPEED_40GB:
397 	default:
398 		incval = I40E_PTP_40GB_INCVAL;
399 		break;
400 	}
401 
402 	/* Write the new increment value into the increment register. The
403 	 * hardware will not update the clock until both registers have been
404 	 * written.
405 	 */
406 	wr32(hw, I40E_PRTTSYN_INC_L, incval & 0xFFFFFFFF);
407 	wr32(hw, I40E_PRTTSYN_INC_H, incval >> 32);
408 
409 	/* Update the base adjustement value. */
410 	ACCESS_ONCE(pf->ptp_base_adj) = incval;
411 	smp_mb(); /* Force the above update. */
412 }
413 
414 /**
415  * i40e_ptp_get_ts_config - ioctl interface to read the HW timestamping
416  * @pf: Board private structure
417  * @ifreq: ioctl data
418  *
419  * Obtain the current hardware timestamping settigs as requested. To do this,
420  * keep a shadow copy of the timestamp settings rather than attempting to
421  * deconstruct it from the registers.
422  **/
423 int i40e_ptp_get_ts_config(struct i40e_pf *pf, struct ifreq *ifr)
424 {
425 	struct hwtstamp_config *config = &pf->tstamp_config;
426 
427 	if (!(pf->flags & I40E_FLAG_PTP))
428 		return -EOPNOTSUPP;
429 
430 	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
431 		-EFAULT : 0;
432 }
433 
434 /**
435  * i40e_ptp_set_timestamp_mode - setup hardware for requested timestamp mode
436  * @pf: Board private structure
437  * @config: hwtstamp settings requested or saved
438  *
439  * Control hardware registers to enter the specific mode requested by the
440  * user. Also used during reset path to ensure that timestamp settings are
441  * maintained.
442  *
443  * Note: modifies config in place, and may update the requested mode to be
444  * more broad if the specific filter is not directly supported.
445  **/
446 static int i40e_ptp_set_timestamp_mode(struct i40e_pf *pf,
447 				       struct hwtstamp_config *config)
448 {
449 	struct i40e_hw *hw = &pf->hw;
450 	u32 tsyntype, regval;
451 
452 	/* Reserved for future extensions. */
453 	if (config->flags)
454 		return -EINVAL;
455 
456 	switch (config->tx_type) {
457 	case HWTSTAMP_TX_OFF:
458 		pf->ptp_tx = false;
459 		break;
460 	case HWTSTAMP_TX_ON:
461 		pf->ptp_tx = true;
462 		break;
463 	default:
464 		return -ERANGE;
465 	}
466 
467 	switch (config->rx_filter) {
468 	case HWTSTAMP_FILTER_NONE:
469 		pf->ptp_rx = false;
470 		tsyntype = 0;
471 		break;
472 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
473 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
474 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
475 		pf->ptp_rx = true;
476 		tsyntype = I40E_PRTTSYN_CTL1_V1MESSTYPE0_MASK |
477 			   I40E_PRTTSYN_CTL1_TSYNTYPE_V1 |
478 			   I40E_PRTTSYN_CTL1_UDP_ENA_MASK;
479 		config->rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
480 		break;
481 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
482 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
483 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
484 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
485 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
486 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
487 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
488 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
489 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
490 		pf->ptp_rx = true;
491 		tsyntype = I40E_PRTTSYN_CTL1_V2MESSTYPE0_MASK |
492 			   I40E_PRTTSYN_CTL1_TSYNTYPE_V2 |
493 			   I40E_PRTTSYN_CTL1_UDP_ENA_MASK;
494 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
495 		break;
496 	case HWTSTAMP_FILTER_ALL:
497 	default:
498 		return -ERANGE;
499 	}
500 
501 	/* Clear out all 1588-related registers to clear and unlatch them. */
502 	rd32(hw, I40E_PRTTSYN_STAT_0);
503 	rd32(hw, I40E_PRTTSYN_TXTIME_H);
504 	rd32(hw, I40E_PRTTSYN_RXTIME_H(0));
505 	rd32(hw, I40E_PRTTSYN_RXTIME_H(1));
506 	rd32(hw, I40E_PRTTSYN_RXTIME_H(2));
507 	rd32(hw, I40E_PRTTSYN_RXTIME_H(3));
508 
509 	/* Enable/disable the Tx timestamp interrupt based on user input. */
510 	regval = rd32(hw, I40E_PRTTSYN_CTL0);
511 	if (pf->ptp_tx)
512 		regval |= I40E_PRTTSYN_CTL0_TXTIME_INT_ENA_MASK;
513 	else
514 		regval &= ~I40E_PRTTSYN_CTL0_TXTIME_INT_ENA_MASK;
515 	wr32(hw, I40E_PRTTSYN_CTL0, regval);
516 
517 	regval = rd32(hw, I40E_PFINT_ICR0_ENA);
518 	if (pf->ptp_tx)
519 		regval |= I40E_PFINT_ICR0_ENA_TIMESYNC_MASK;
520 	else
521 		regval &= ~I40E_PFINT_ICR0_ENA_TIMESYNC_MASK;
522 	wr32(hw, I40E_PFINT_ICR0_ENA, regval);
523 
524 	/* There is no simple on/off switch for Rx. To "disable" Rx support,
525 	 * ignore any received timestamps, rather than turn off the clock.
526 	 */
527 	if (pf->ptp_rx) {
528 		regval = rd32(hw, I40E_PRTTSYN_CTL1);
529 		/* clear everything but the enable bit */
530 		regval &= I40E_PRTTSYN_CTL1_TSYNENA_MASK;
531 		/* now enable bits for desired Rx timestamps */
532 		regval |= tsyntype;
533 		wr32(hw, I40E_PRTTSYN_CTL1, regval);
534 	}
535 
536 	return 0;
537 }
538 
539 /**
540  * i40e_ptp_set_ts_config - ioctl interface to control the HW timestamping
541  * @pf: Board private structure
542  * @ifreq: ioctl data
543  *
544  * Respond to the user filter requests and make the appropriate hardware
545  * changes here. The XL710 cannot support splitting of the Tx/Rx timestamping
546  * logic, so keep track in software of whether to indicate these timestamps
547  * or not.
548  *
549  * It is permissible to "upgrade" the user request to a broader filter, as long
550  * as the user receives the timestamps they care about and the user is notified
551  * the filter has been broadened.
552  **/
553 int i40e_ptp_set_ts_config(struct i40e_pf *pf, struct ifreq *ifr)
554 {
555 	struct hwtstamp_config config;
556 	int err;
557 
558 	if (!(pf->flags & I40E_FLAG_PTP))
559 		return -EOPNOTSUPP;
560 
561 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
562 		return -EFAULT;
563 
564 	err = i40e_ptp_set_timestamp_mode(pf, &config);
565 	if (err)
566 		return err;
567 
568 	/* save these settings for future reference */
569 	pf->tstamp_config = config;
570 
571 	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
572 		-EFAULT : 0;
573 }
574 
575 /**
576  * i40e_ptp_create_clock - Create PTP clock device for userspace
577  * @pf: Board private structure
578  *
579  * This function creates a new PTP clock device. It only creates one if we
580  * don't already have one, so it is safe to call. Will return error if it
581  * can't create one, but success if we already have a device. Should be used
582  * by i40e_ptp_init to create clock initially, and prevent global resets from
583  * creating new clock devices.
584  **/
585 static long i40e_ptp_create_clock(struct i40e_pf *pf)
586 {
587 	/* no need to create a clock device if we already have one */
588 	if (!IS_ERR_OR_NULL(pf->ptp_clock))
589 		return 0;
590 
591 	strncpy(pf->ptp_caps.name, i40e_driver_name, sizeof(pf->ptp_caps.name));
592 	pf->ptp_caps.owner = THIS_MODULE;
593 	pf->ptp_caps.max_adj = 999999999;
594 	pf->ptp_caps.n_ext_ts = 0;
595 	pf->ptp_caps.pps = 0;
596 	pf->ptp_caps.adjfreq = i40e_ptp_adjfreq;
597 	pf->ptp_caps.adjtime = i40e_ptp_adjtime;
598 	pf->ptp_caps.gettime = i40e_ptp_gettime;
599 	pf->ptp_caps.settime = i40e_ptp_settime;
600 	pf->ptp_caps.enable = i40e_ptp_feature_enable;
601 
602 	/* Attempt to register the clock before enabling the hardware. */
603 	pf->ptp_clock = ptp_clock_register(&pf->ptp_caps, &pf->pdev->dev);
604 	if (IS_ERR(pf->ptp_clock)) {
605 		return PTR_ERR(pf->ptp_clock);
606 	}
607 
608 	/* clear the hwtstamp settings here during clock create, instead of
609 	 * during regular init, so that we can maintain settings across a
610 	 * reset or suspend.
611 	 */
612 	pf->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
613 	pf->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
614 
615 	return 0;
616 }
617 
618 /**
619  * i40e_ptp_init - Initialize the 1588 support after device probe or reset
620  * @pf: Board private structure
621  *
622  * This function sets device up for 1588 support. The first time it is run, it
623  * will create a PHC clock device. It does not create a clock device if one
624  * already exists. It also reconfigures the device after a reset.
625  **/
626 void i40e_ptp_init(struct i40e_pf *pf)
627 {
628 	struct net_device *netdev = pf->vsi[pf->lan_vsi]->netdev;
629 	struct i40e_hw *hw = &pf->hw;
630 	u32 pf_id;
631 	long err;
632 
633 	/* Only one PF is assigned to control 1588 logic per port. Do not
634 	 * enable any support for PFs not assigned via PRTTSYN_CTL0.PF_ID
635 	 */
636 	pf_id = (rd32(hw, I40E_PRTTSYN_CTL0) & I40E_PRTTSYN_CTL0_PF_ID_MASK) >>
637 		I40E_PRTTSYN_CTL0_PF_ID_SHIFT;
638 	if (hw->pf_id != pf_id) {
639 		pf->flags &= ~I40E_FLAG_PTP;
640 		dev_info(&pf->pdev->dev, "%s: PTP not supported on %s\n",
641 			 __func__,
642 			 netdev->name);
643 		return;
644 	}
645 
646 	/* we have to initialize the lock first, since we can't control
647 	 * when the user will enter the PHC device entry points
648 	 */
649 	spin_lock_init(&pf->tmreg_lock);
650 
651 	/* ensure we have a clock device */
652 	err = i40e_ptp_create_clock(pf);
653 	if (err) {
654 		pf->ptp_clock = NULL;
655 		dev_err(&pf->pdev->dev, "%s: ptp_clock_register failed\n",
656 			__func__);
657 	} else {
658 		struct timespec ts;
659 		u32 regval;
660 
661 		dev_info(&pf->pdev->dev, "%s: added PHC on %s\n", __func__,
662 			 netdev->name);
663 		pf->flags |= I40E_FLAG_PTP;
664 
665 		/* Ensure the clocks are running. */
666 		regval = rd32(hw, I40E_PRTTSYN_CTL0);
667 		regval |= I40E_PRTTSYN_CTL0_TSYNENA_MASK;
668 		wr32(hw, I40E_PRTTSYN_CTL0, regval);
669 		regval = rd32(hw, I40E_PRTTSYN_CTL1);
670 		regval |= I40E_PRTTSYN_CTL1_TSYNENA_MASK;
671 		wr32(hw, I40E_PRTTSYN_CTL1, regval);
672 
673 		/* Set the increment value per clock tick. */
674 		i40e_ptp_set_increment(pf);
675 
676 		/* reset timestamping mode */
677 		i40e_ptp_set_timestamp_mode(pf, &pf->tstamp_config);
678 
679 		/* Set the clock value. */
680 		ts = ktime_to_timespec(ktime_get_real());
681 		i40e_ptp_settime(&pf->ptp_caps, &ts);
682 	}
683 }
684 
685 /**
686  * i40e_ptp_stop - Disable the driver/hardware support and unregister the PHC
687  * @pf: Board private structure
688  *
689  * This function handles the cleanup work required from the initialization by
690  * clearing out the important information and unregistering the PHC.
691  **/
692 void i40e_ptp_stop(struct i40e_pf *pf)
693 {
694 	pf->flags &= ~I40E_FLAG_PTP;
695 	pf->ptp_tx = false;
696 	pf->ptp_rx = false;
697 
698 	if (pf->ptp_tx_skb) {
699 		dev_kfree_skb_any(pf->ptp_tx_skb);
700 		pf->ptp_tx_skb = NULL;
701 		clear_bit_unlock(__I40E_PTP_TX_IN_PROGRESS, &pf->state);
702 	}
703 
704 	if (pf->ptp_clock) {
705 		ptp_clock_unregister(pf->ptp_clock);
706 		pf->ptp_clock = NULL;
707 		dev_info(&pf->pdev->dev, "%s: removed PHC on %s\n", __func__,
708 			 pf->vsi[pf->lan_vsi]->netdev->name);
709 	}
710 }
711