1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #include <linux/ptp_classify.h>
4 
5 #include "lan966x_main.h"
6 #include "vcap_api.h"
7 #include "vcap_api_client.h"
8 
9 #define LAN966X_MAX_PTP_ID	512
10 
11 /* Represents 1ppm adjustment in 2^59 format with 6.037735849ns as reference
12  * The value is calculated as following: (1/1000000)/((2^-59)/6.037735849)
13  */
14 #define LAN966X_1PPM_FORMAT		3480517749723LL
15 
16 /* Represents 1ppb adjustment in 2^29 format with 6.037735849ns as reference
17  * The value is calculated as following: (1/1000000000)/((2^59)/6.037735849)
18  */
19 #define LAN966X_1PPB_FORMAT		3480517749LL
20 
21 #define TOD_ACC_PIN		0x7
22 
23 /* This represents the base rule ID for the PTP rules that are added in the
24  * VCAP to trap frames to CPU. This number needs to be bigger than the maximum
25  * number of entries that can exist in the VCAP.
26  */
27 #define LAN966X_VCAP_PTP_RULE_ID	1000000
28 #define LAN966X_VCAP_L2_PTP_TRAP	(LAN966X_VCAP_PTP_RULE_ID + 0)
29 #define LAN966X_VCAP_IPV4_EV_PTP_TRAP	(LAN966X_VCAP_PTP_RULE_ID + 1)
30 #define LAN966X_VCAP_IPV4_GEN_PTP_TRAP	(LAN966X_VCAP_PTP_RULE_ID + 2)
31 #define LAN966X_VCAP_IPV6_EV_PTP_TRAP	(LAN966X_VCAP_PTP_RULE_ID + 3)
32 #define LAN966X_VCAP_IPV6_GEN_PTP_TRAP	(LAN966X_VCAP_PTP_RULE_ID + 4)
33 
34 enum {
35 	PTP_PIN_ACTION_IDLE = 0,
36 	PTP_PIN_ACTION_LOAD,
37 	PTP_PIN_ACTION_SAVE,
38 	PTP_PIN_ACTION_CLOCK,
39 	PTP_PIN_ACTION_DELTA,
40 	PTP_PIN_ACTION_TOD
41 };
42 
43 static u64 lan966x_ptp_get_nominal_value(void)
44 {
45 	/* This is the default value that for each system clock, the time of day
46 	 * is increased. It has the format 5.59 nanosecond.
47 	 */
48 	return 0x304d4873ecade305;
49 }
50 
51 static int lan966x_ptp_add_trap(struct lan966x_port *port,
52 				int (*add_ptp_key)(struct vcap_rule *vrule,
53 						   struct lan966x_port*),
54 				u32 rule_id,
55 				u16 proto)
56 {
57 	struct lan966x *lan966x = port->lan966x;
58 	struct vcap_rule *vrule;
59 	int err;
60 
61 	vrule = vcap_get_rule(lan966x->vcap_ctrl, rule_id);
62 	if (vrule) {
63 		u32 value, mask;
64 
65 		/* Just modify the ingress port mask and exit */
66 		vcap_rule_get_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
67 				      &value, &mask);
68 		mask &= ~BIT(port->chip_port);
69 		vcap_rule_mod_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
70 				      value, mask);
71 
72 		err = vcap_mod_rule(vrule);
73 		goto free_rule;
74 	}
75 
76 	vrule = vcap_alloc_rule(lan966x->vcap_ctrl, port->dev,
77 				LAN966X_VCAP_CID_IS2_L0,
78 				VCAP_USER_PTP, 0, rule_id);
79 	if (IS_ERR(vrule))
80 		return PTR_ERR(vrule);
81 
82 	err = add_ptp_key(vrule, port);
83 	if (err)
84 		goto free_rule;
85 
86 	err = vcap_rule_add_action_bit(vrule, VCAP_AF_CPU_COPY_ENA, VCAP_BIT_1);
87 	err |= vcap_rule_add_action_u32(vrule, VCAP_AF_MASK_MODE, LAN966X_PMM_REPLACE);
88 	err |= vcap_val_rule(vrule, proto);
89 	if (err)
90 		goto free_rule;
91 
92 	err = vcap_add_rule(vrule);
93 
94 free_rule:
95 	/* Free the local copy of the rule */
96 	vcap_free_rule(vrule);
97 	return err;
98 }
99 
100 static int lan966x_ptp_del_trap(struct lan966x_port *port,
101 				u32 rule_id)
102 {
103 	struct lan966x *lan966x = port->lan966x;
104 	struct vcap_rule *vrule;
105 	u32 value, mask;
106 	int err;
107 
108 	vrule = vcap_get_rule(lan966x->vcap_ctrl, rule_id);
109 	if (!vrule)
110 		return -EEXIST;
111 
112 	vcap_rule_get_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK, &value, &mask);
113 	mask |= BIT(port->chip_port);
114 
115 	/* No other port requires this trap, so it is safe to remove it */
116 	if (mask == GENMASK(lan966x->num_phys_ports, 0)) {
117 		err = vcap_del_rule(lan966x->vcap_ctrl, port->dev, rule_id);
118 		goto free_rule;
119 	}
120 
121 	vcap_rule_mod_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK, value, mask);
122 	err = vcap_mod_rule(vrule);
123 
124 free_rule:
125 	vcap_free_rule(vrule);
126 	return err;
127 }
128 
129 static int lan966x_ptp_add_l2_key(struct vcap_rule *vrule,
130 				  struct lan966x_port *port)
131 {
132 	return vcap_rule_add_key_u32(vrule, VCAP_KF_ETYPE, ETH_P_1588, ~0);
133 }
134 
135 static int lan966x_ptp_add_ip_event_key(struct vcap_rule *vrule,
136 					struct lan966x_port *port)
137 {
138 	return vcap_rule_add_key_u32(vrule, VCAP_KF_L4_DPORT, PTP_EV_PORT, ~0) ||
139 	       vcap_rule_add_key_bit(vrule, VCAP_KF_TCP_IS, VCAP_BIT_0);
140 }
141 
142 static int lan966x_ptp_add_ip_general_key(struct vcap_rule *vrule,
143 					  struct lan966x_port *port)
144 {
145 	return vcap_rule_add_key_u32(vrule, VCAP_KF_L4_DPORT, PTP_GEN_PORT, ~0) ||
146 	       vcap_rule_add_key_bit(vrule, VCAP_KF_TCP_IS, VCAP_BIT_0);
147 }
148 
149 static int lan966x_ptp_add_l2_rule(struct lan966x_port *port)
150 {
151 	return lan966x_ptp_add_trap(port, lan966x_ptp_add_l2_key,
152 				    LAN966X_VCAP_L2_PTP_TRAP, ETH_P_ALL);
153 }
154 
155 static int lan966x_ptp_add_ipv4_rules(struct lan966x_port *port)
156 {
157 	int err;
158 
159 	err = lan966x_ptp_add_trap(port, lan966x_ptp_add_ip_event_key,
160 				   LAN966X_VCAP_IPV4_EV_PTP_TRAP, ETH_P_IP);
161 	if (err)
162 		return err;
163 
164 	err = lan966x_ptp_add_trap(port, lan966x_ptp_add_ip_general_key,
165 				   LAN966X_VCAP_IPV4_GEN_PTP_TRAP, ETH_P_IP);
166 	if (err)
167 		lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV4_EV_PTP_TRAP);
168 
169 	return err;
170 }
171 
172 static int lan966x_ptp_add_ipv6_rules(struct lan966x_port *port)
173 {
174 	int err;
175 
176 	err = lan966x_ptp_add_trap(port, lan966x_ptp_add_ip_event_key,
177 				   LAN966X_VCAP_IPV6_EV_PTP_TRAP, ETH_P_IPV6);
178 	if (err)
179 		return err;
180 
181 	err = lan966x_ptp_add_trap(port, lan966x_ptp_add_ip_general_key,
182 				   LAN966X_VCAP_IPV6_GEN_PTP_TRAP, ETH_P_IPV6);
183 	if (err)
184 		lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV6_EV_PTP_TRAP);
185 
186 	return err;
187 }
188 
189 static int lan966x_ptp_del_l2_rule(struct lan966x_port *port)
190 {
191 	return lan966x_ptp_del_trap(port, LAN966X_VCAP_L2_PTP_TRAP);
192 }
193 
194 static int lan966x_ptp_del_ipv4_rules(struct lan966x_port *port)
195 {
196 	int err;
197 
198 	err = lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV4_EV_PTP_TRAP);
199 	err |= lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV4_GEN_PTP_TRAP);
200 
201 	return err;
202 }
203 
204 static int lan966x_ptp_del_ipv6_rules(struct lan966x_port *port)
205 {
206 	int err;
207 
208 	err = lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV6_EV_PTP_TRAP);
209 	err |= lan966x_ptp_del_trap(port, LAN966X_VCAP_IPV6_GEN_PTP_TRAP);
210 
211 	return err;
212 }
213 
214 static int lan966x_ptp_add_traps(struct lan966x_port *port)
215 {
216 	int err;
217 
218 	err = lan966x_ptp_add_l2_rule(port);
219 	if (err)
220 		goto err_l2;
221 
222 	err = lan966x_ptp_add_ipv4_rules(port);
223 	if (err)
224 		goto err_ipv4;
225 
226 	err = lan966x_ptp_add_ipv6_rules(port);
227 	if (err)
228 		goto err_ipv6;
229 
230 	return err;
231 
232 err_ipv6:
233 	lan966x_ptp_del_ipv4_rules(port);
234 err_ipv4:
235 	lan966x_ptp_del_l2_rule(port);
236 err_l2:
237 	return err;
238 }
239 
240 int lan966x_ptp_del_traps(struct lan966x_port *port)
241 {
242 	int err;
243 
244 	err = lan966x_ptp_del_l2_rule(port);
245 	err |= lan966x_ptp_del_ipv4_rules(port);
246 	err |= lan966x_ptp_del_ipv6_rules(port);
247 
248 	return err;
249 }
250 
251 int lan966x_ptp_setup_traps(struct lan966x_port *port, struct ifreq *ifr)
252 {
253 	struct hwtstamp_config cfg;
254 
255 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
256 		return -EFAULT;
257 
258 	if (cfg.rx_filter == HWTSTAMP_FILTER_NONE)
259 		return lan966x_ptp_del_traps(port);
260 	else
261 		return lan966x_ptp_add_traps(port);
262 }
263 
264 int lan966x_ptp_hwtstamp_set(struct lan966x_port *port, struct ifreq *ifr)
265 {
266 	struct lan966x *lan966x = port->lan966x;
267 	struct hwtstamp_config cfg;
268 	struct lan966x_phc *phc;
269 
270 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
271 		return -EFAULT;
272 
273 	switch (cfg.tx_type) {
274 	case HWTSTAMP_TX_ON:
275 		port->ptp_cmd = IFH_REW_OP_TWO_STEP_PTP;
276 		break;
277 	case HWTSTAMP_TX_ONESTEP_SYNC:
278 		port->ptp_cmd = IFH_REW_OP_ONE_STEP_PTP;
279 		break;
280 	case HWTSTAMP_TX_OFF:
281 		port->ptp_cmd = IFH_REW_OP_NOOP;
282 		break;
283 	default:
284 		return -ERANGE;
285 	}
286 
287 	switch (cfg.rx_filter) {
288 	case HWTSTAMP_FILTER_NONE:
289 		break;
290 	case HWTSTAMP_FILTER_ALL:
291 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
292 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
293 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
294 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
295 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
296 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
297 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
298 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
299 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
300 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
301 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
302 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
303 	case HWTSTAMP_FILTER_NTP_ALL:
304 		cfg.rx_filter = HWTSTAMP_FILTER_ALL;
305 		break;
306 	default:
307 		return -ERANGE;
308 	}
309 
310 	/* Commit back the result & save it */
311 	mutex_lock(&lan966x->ptp_lock);
312 	phc = &lan966x->phc[LAN966X_PHC_PORT];
313 	memcpy(&phc->hwtstamp_config, &cfg, sizeof(cfg));
314 	mutex_unlock(&lan966x->ptp_lock);
315 
316 	return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
317 }
318 
319 int lan966x_ptp_hwtstamp_get(struct lan966x_port *port, struct ifreq *ifr)
320 {
321 	struct lan966x *lan966x = port->lan966x;
322 	struct lan966x_phc *phc;
323 
324 	phc = &lan966x->phc[LAN966X_PHC_PORT];
325 	return copy_to_user(ifr->ifr_data, &phc->hwtstamp_config,
326 			    sizeof(phc->hwtstamp_config)) ? -EFAULT : 0;
327 }
328 
329 static int lan966x_ptp_classify(struct lan966x_port *port, struct sk_buff *skb)
330 {
331 	struct ptp_header *header;
332 	u8 msgtype;
333 	int type;
334 
335 	if (port->ptp_cmd == IFH_REW_OP_NOOP)
336 		return IFH_REW_OP_NOOP;
337 
338 	type = ptp_classify_raw(skb);
339 	if (type == PTP_CLASS_NONE)
340 		return IFH_REW_OP_NOOP;
341 
342 	header = ptp_parse_header(skb, type);
343 	if (!header)
344 		return IFH_REW_OP_NOOP;
345 
346 	if (port->ptp_cmd == IFH_REW_OP_TWO_STEP_PTP)
347 		return IFH_REW_OP_TWO_STEP_PTP;
348 
349 	/* If it is sync and run 1 step then set the correct operation,
350 	 * otherwise run as 2 step
351 	 */
352 	msgtype = ptp_get_msgtype(header, type);
353 	if ((msgtype & 0xf) == 0)
354 		return IFH_REW_OP_ONE_STEP_PTP;
355 
356 	return IFH_REW_OP_TWO_STEP_PTP;
357 }
358 
359 static void lan966x_ptp_txtstamp_old_release(struct lan966x_port *port)
360 {
361 	struct sk_buff *skb, *skb_tmp;
362 	unsigned long flags;
363 
364 	spin_lock_irqsave(&port->tx_skbs.lock, flags);
365 	skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) {
366 		if time_after(LAN966X_SKB_CB(skb)->jiffies + LAN966X_PTP_TIMEOUT,
367 			      jiffies)
368 			break;
369 
370 		__skb_unlink(skb, &port->tx_skbs);
371 		dev_kfree_skb_any(skb);
372 	}
373 	spin_unlock_irqrestore(&port->tx_skbs.lock, flags);
374 }
375 
376 int lan966x_ptp_txtstamp_request(struct lan966x_port *port,
377 				 struct sk_buff *skb)
378 {
379 	struct lan966x *lan966x = port->lan966x;
380 	unsigned long flags;
381 	u8 rew_op;
382 
383 	rew_op = lan966x_ptp_classify(port, skb);
384 	LAN966X_SKB_CB(skb)->rew_op = rew_op;
385 
386 	if (rew_op != IFH_REW_OP_TWO_STEP_PTP)
387 		return 0;
388 
389 	lan966x_ptp_txtstamp_old_release(port);
390 
391 	spin_lock_irqsave(&lan966x->ptp_ts_id_lock, flags);
392 	if (lan966x->ptp_skbs == LAN966X_MAX_PTP_ID) {
393 		spin_unlock_irqrestore(&lan966x->ptp_ts_id_lock, flags);
394 		return -EBUSY;
395 	}
396 
397 	skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
398 
399 	skb_queue_tail(&port->tx_skbs, skb);
400 	LAN966X_SKB_CB(skb)->ts_id = port->ts_id;
401 	LAN966X_SKB_CB(skb)->jiffies = jiffies;
402 
403 	lan966x->ptp_skbs++;
404 	port->ts_id++;
405 	if (port->ts_id == LAN966X_MAX_PTP_ID)
406 		port->ts_id = 0;
407 
408 	spin_unlock_irqrestore(&lan966x->ptp_ts_id_lock, flags);
409 
410 	return 0;
411 }
412 
413 void lan966x_ptp_txtstamp_release(struct lan966x_port *port,
414 				  struct sk_buff *skb)
415 {
416 	struct lan966x *lan966x = port->lan966x;
417 	unsigned long flags;
418 
419 	spin_lock_irqsave(&lan966x->ptp_ts_id_lock, flags);
420 	port->ts_id--;
421 	lan966x->ptp_skbs--;
422 	skb_unlink(skb, &port->tx_skbs);
423 	spin_unlock_irqrestore(&lan966x->ptp_ts_id_lock, flags);
424 }
425 
426 static void lan966x_get_hwtimestamp(struct lan966x *lan966x,
427 				    struct timespec64 *ts,
428 				    u32 nsec)
429 {
430 	/* Read current PTP time to get seconds */
431 	unsigned long flags;
432 	u32 curr_nsec;
433 
434 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
435 
436 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_SAVE) |
437 		PTP_PIN_CFG_PIN_DOM_SET(LAN966X_PHC_PORT) |
438 		PTP_PIN_CFG_PIN_SYNC_SET(0),
439 		PTP_PIN_CFG_PIN_ACTION |
440 		PTP_PIN_CFG_PIN_DOM |
441 		PTP_PIN_CFG_PIN_SYNC,
442 		lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
443 
444 	ts->tv_sec = lan_rd(lan966x, PTP_TOD_SEC_LSB(TOD_ACC_PIN));
445 	curr_nsec = lan_rd(lan966x, PTP_TOD_NSEC(TOD_ACC_PIN));
446 
447 	ts->tv_nsec = nsec;
448 
449 	/* Sec has incremented since the ts was registered */
450 	if (curr_nsec < nsec)
451 		ts->tv_sec--;
452 
453 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
454 }
455 
456 irqreturn_t lan966x_ptp_irq_handler(int irq, void *args)
457 {
458 	int budget = LAN966X_MAX_PTP_ID;
459 	struct lan966x *lan966x = args;
460 
461 	while (budget--) {
462 		struct sk_buff *skb, *skb_tmp, *skb_match = NULL;
463 		struct skb_shared_hwtstamps shhwtstamps;
464 		struct lan966x_port *port;
465 		struct timespec64 ts;
466 		unsigned long flags;
467 		u32 val, id, txport;
468 		u32 delay;
469 
470 		val = lan_rd(lan966x, PTP_TWOSTEP_CTRL);
471 
472 		/* Check if a timestamp can be retrieved */
473 		if (!(val & PTP_TWOSTEP_CTRL_VLD))
474 			break;
475 
476 		WARN_ON(val & PTP_TWOSTEP_CTRL_OVFL);
477 
478 		if (!(val & PTP_TWOSTEP_CTRL_STAMP_TX))
479 			continue;
480 
481 		/* Retrieve the ts Tx port */
482 		txport = PTP_TWOSTEP_CTRL_STAMP_PORT_GET(val);
483 
484 		/* Retrieve its associated skb */
485 		port = lan966x->ports[txport];
486 
487 		/* Retrieve the delay */
488 		delay = lan_rd(lan966x, PTP_TWOSTEP_STAMP);
489 		delay = PTP_TWOSTEP_STAMP_STAMP_NSEC_GET(delay);
490 
491 		/* Get next timestamp from fifo, which needs to be the
492 		 * rx timestamp which represents the id of the frame
493 		 */
494 		lan_rmw(PTP_TWOSTEP_CTRL_NXT_SET(1),
495 			PTP_TWOSTEP_CTRL_NXT,
496 			lan966x, PTP_TWOSTEP_CTRL);
497 
498 		val = lan_rd(lan966x, PTP_TWOSTEP_CTRL);
499 
500 		/* Check if a timestamp can be retried */
501 		if (!(val & PTP_TWOSTEP_CTRL_VLD))
502 			break;
503 
504 		/* Read RX timestamping to get the ID */
505 		id = lan_rd(lan966x, PTP_TWOSTEP_STAMP);
506 
507 		spin_lock_irqsave(&port->tx_skbs.lock, flags);
508 		skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) {
509 			if (LAN966X_SKB_CB(skb)->ts_id != id)
510 				continue;
511 
512 			__skb_unlink(skb, &port->tx_skbs);
513 			skb_match = skb;
514 			break;
515 		}
516 		spin_unlock_irqrestore(&port->tx_skbs.lock, flags);
517 
518 		/* Next ts */
519 		lan_rmw(PTP_TWOSTEP_CTRL_NXT_SET(1),
520 			PTP_TWOSTEP_CTRL_NXT,
521 			lan966x, PTP_TWOSTEP_CTRL);
522 
523 		if (WARN_ON(!skb_match))
524 			continue;
525 
526 		spin_lock_irqsave(&lan966x->ptp_ts_id_lock, flags);
527 		lan966x->ptp_skbs--;
528 		spin_unlock_irqrestore(&lan966x->ptp_ts_id_lock, flags);
529 
530 		/* Get the h/w timestamp */
531 		lan966x_get_hwtimestamp(lan966x, &ts, delay);
532 
533 		/* Set the timestamp into the skb */
534 		shhwtstamps.hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec);
535 		skb_tstamp_tx(skb_match, &shhwtstamps);
536 
537 		dev_kfree_skb_any(skb_match);
538 	}
539 
540 	return IRQ_HANDLED;
541 }
542 
543 irqreturn_t lan966x_ptp_ext_irq_handler(int irq, void *args)
544 {
545 	struct lan966x *lan966x = args;
546 	struct lan966x_phc *phc;
547 	unsigned long flags;
548 	u64 time = 0;
549 	time64_t s;
550 	int pin, i;
551 	s64 ns;
552 
553 	if (!(lan_rd(lan966x, PTP_PIN_INTR)))
554 		return IRQ_NONE;
555 
556 	/* Go through all domains and see which pin generated the interrupt */
557 	for (i = 0; i < LAN966X_PHC_COUNT; ++i) {
558 		struct ptp_clock_event ptp_event = {0};
559 
560 		phc = &lan966x->phc[i];
561 		pin = ptp_find_pin_unlocked(phc->clock, PTP_PF_EXTTS, 0);
562 		if (pin == -1)
563 			continue;
564 
565 		if (!(lan_rd(lan966x, PTP_PIN_INTR) & BIT(pin)))
566 			continue;
567 
568 		spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
569 
570 		/* Enable to get the new interrupt.
571 		 * By writing 1 it clears the bit
572 		 */
573 		lan_wr(BIT(pin), lan966x, PTP_PIN_INTR);
574 
575 		/* Get current time */
576 		s = lan_rd(lan966x, PTP_TOD_SEC_MSB(pin));
577 		s <<= 32;
578 		s |= lan_rd(lan966x, PTP_TOD_SEC_LSB(pin));
579 		ns = lan_rd(lan966x, PTP_TOD_NSEC(pin));
580 		ns &= PTP_TOD_NSEC_TOD_NSEC;
581 
582 		spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
583 
584 		if ((ns & 0xFFFFFFF0) == 0x3FFFFFF0) {
585 			s--;
586 			ns &= 0xf;
587 			ns += 999999984;
588 		}
589 		time = ktime_set(s, ns);
590 
591 		ptp_event.index = pin;
592 		ptp_event.timestamp = time;
593 		ptp_event.type = PTP_CLOCK_EXTTS;
594 		ptp_clock_event(phc->clock, &ptp_event);
595 	}
596 
597 	return IRQ_HANDLED;
598 }
599 
600 static int lan966x_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
601 {
602 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
603 	struct lan966x *lan966x = phc->lan966x;
604 	unsigned long flags;
605 	bool neg_adj = 0;
606 	u64 tod_inc;
607 	u64 ref;
608 
609 	if (!scaled_ppm)
610 		return 0;
611 
612 	if (scaled_ppm < 0) {
613 		neg_adj = 1;
614 		scaled_ppm = -scaled_ppm;
615 	}
616 
617 	tod_inc = lan966x_ptp_get_nominal_value();
618 
619 	/* The multiplication is split in 2 separate additions because of
620 	 * overflow issues. If scaled_ppm with 16bit fractional part was bigger
621 	 * than 20ppm then we got overflow.
622 	 */
623 	ref = LAN966X_1PPM_FORMAT * (scaled_ppm >> 16);
624 	ref += (LAN966X_1PPM_FORMAT * (0xffff & scaled_ppm)) >> 16;
625 	tod_inc = neg_adj ? tod_inc - ref : tod_inc + ref;
626 
627 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
628 
629 	lan_rmw(PTP_DOM_CFG_CLKCFG_DIS_SET(1 << BIT(phc->index)),
630 		PTP_DOM_CFG_CLKCFG_DIS,
631 		lan966x, PTP_DOM_CFG);
632 
633 	lan_wr((u32)tod_inc & 0xFFFFFFFF, lan966x,
634 	       PTP_CLK_PER_CFG(phc->index, 0));
635 	lan_wr((u32)(tod_inc >> 32), lan966x,
636 	       PTP_CLK_PER_CFG(phc->index, 1));
637 
638 	lan_rmw(PTP_DOM_CFG_CLKCFG_DIS_SET(0),
639 		PTP_DOM_CFG_CLKCFG_DIS,
640 		lan966x, PTP_DOM_CFG);
641 
642 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
643 
644 	return 0;
645 }
646 
647 static int lan966x_ptp_settime64(struct ptp_clock_info *ptp,
648 				 const struct timespec64 *ts)
649 {
650 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
651 	struct lan966x *lan966x = phc->lan966x;
652 	unsigned long flags;
653 
654 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
655 
656 	/* Must be in IDLE mode before the time can be loaded */
657 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_IDLE) |
658 		PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
659 		PTP_PIN_CFG_PIN_SYNC_SET(0),
660 		PTP_PIN_CFG_PIN_ACTION |
661 		PTP_PIN_CFG_PIN_DOM |
662 		PTP_PIN_CFG_PIN_SYNC,
663 		lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
664 
665 	/* Set new value */
666 	lan_wr(PTP_TOD_SEC_MSB_TOD_SEC_MSB_SET(upper_32_bits(ts->tv_sec)),
667 	       lan966x, PTP_TOD_SEC_MSB(TOD_ACC_PIN));
668 	lan_wr(lower_32_bits(ts->tv_sec),
669 	       lan966x, PTP_TOD_SEC_LSB(TOD_ACC_PIN));
670 	lan_wr(ts->tv_nsec, lan966x, PTP_TOD_NSEC(TOD_ACC_PIN));
671 
672 	/* Apply new values */
673 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_LOAD) |
674 		PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
675 		PTP_PIN_CFG_PIN_SYNC_SET(0),
676 		PTP_PIN_CFG_PIN_ACTION |
677 		PTP_PIN_CFG_PIN_DOM |
678 		PTP_PIN_CFG_PIN_SYNC,
679 		lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
680 
681 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
682 
683 	return 0;
684 }
685 
686 int lan966x_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts)
687 {
688 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
689 	struct lan966x *lan966x = phc->lan966x;
690 	unsigned long flags;
691 	time64_t s;
692 	s64 ns;
693 
694 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
695 
696 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_SAVE) |
697 		PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
698 		PTP_PIN_CFG_PIN_SYNC_SET(0),
699 		PTP_PIN_CFG_PIN_ACTION |
700 		PTP_PIN_CFG_PIN_DOM |
701 		PTP_PIN_CFG_PIN_SYNC,
702 		lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
703 
704 	s = lan_rd(lan966x, PTP_TOD_SEC_MSB(TOD_ACC_PIN));
705 	s <<= 32;
706 	s |= lan_rd(lan966x, PTP_TOD_SEC_LSB(TOD_ACC_PIN));
707 	ns = lan_rd(lan966x, PTP_TOD_NSEC(TOD_ACC_PIN));
708 	ns &= PTP_TOD_NSEC_TOD_NSEC;
709 
710 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
711 
712 	/* Deal with negative values */
713 	if ((ns & 0xFFFFFFF0) == 0x3FFFFFF0) {
714 		s--;
715 		ns &= 0xf;
716 		ns += 999999984;
717 	}
718 
719 	set_normalized_timespec64(ts, s, ns);
720 	return 0;
721 }
722 
723 static int lan966x_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
724 {
725 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
726 	struct lan966x *lan966x = phc->lan966x;
727 
728 	if (delta > -(NSEC_PER_SEC / 2) && delta < (NSEC_PER_SEC / 2)) {
729 		unsigned long flags;
730 
731 		spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
732 
733 		/* Must be in IDLE mode before the time can be loaded */
734 		lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_IDLE) |
735 			PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
736 			PTP_PIN_CFG_PIN_SYNC_SET(0),
737 			PTP_PIN_CFG_PIN_ACTION |
738 			PTP_PIN_CFG_PIN_DOM |
739 			PTP_PIN_CFG_PIN_SYNC,
740 			lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
741 
742 		lan_wr(PTP_TOD_NSEC_TOD_NSEC_SET(delta),
743 		       lan966x, PTP_TOD_NSEC(TOD_ACC_PIN));
744 
745 		/* Adjust time with the value of PTP_TOD_NSEC */
746 		lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_DELTA) |
747 			PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
748 			PTP_PIN_CFG_PIN_SYNC_SET(0),
749 			PTP_PIN_CFG_PIN_ACTION |
750 			PTP_PIN_CFG_PIN_DOM |
751 			PTP_PIN_CFG_PIN_SYNC,
752 			lan966x, PTP_PIN_CFG(TOD_ACC_PIN));
753 
754 		spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
755 	} else {
756 		/* Fall back using lan966x_ptp_settime64 which is not exact */
757 		struct timespec64 ts;
758 		u64 now;
759 
760 		lan966x_ptp_gettime64(ptp, &ts);
761 
762 		now = ktime_to_ns(timespec64_to_ktime(ts));
763 		ts = ns_to_timespec64(now + delta);
764 
765 		lan966x_ptp_settime64(ptp, &ts);
766 	}
767 
768 	return 0;
769 }
770 
771 static int lan966x_ptp_verify(struct ptp_clock_info *ptp, unsigned int pin,
772 			      enum ptp_pin_function func, unsigned int chan)
773 {
774 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
775 	struct lan966x *lan966x = phc->lan966x;
776 	struct ptp_clock_info *info;
777 	int i;
778 
779 	/* Currently support only 1 channel */
780 	if (chan != 0)
781 		return -1;
782 
783 	switch (func) {
784 	case PTP_PF_NONE:
785 	case PTP_PF_PEROUT:
786 	case PTP_PF_EXTTS:
787 		break;
788 	default:
789 		return -1;
790 	}
791 
792 	/* The PTP pins are shared by all the PHC. So it is required to see if
793 	 * the pin is connected to another PHC. The pin is connected to another
794 	 * PHC if that pin already has a function on that PHC.
795 	 */
796 	for (i = 0; i < LAN966X_PHC_COUNT; ++i) {
797 		info = &lan966x->phc[i].info;
798 
799 		/* Ignore the check with ourself */
800 		if (ptp == info)
801 			continue;
802 
803 		if (info->pin_config[pin].func == PTP_PF_PEROUT ||
804 		    info->pin_config[pin].func == PTP_PF_EXTTS)
805 			return -1;
806 	}
807 
808 	return 0;
809 }
810 
811 static int lan966x_ptp_perout(struct ptp_clock_info *ptp,
812 			      struct ptp_clock_request *rq, int on)
813 {
814 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
815 	struct lan966x *lan966x = phc->lan966x;
816 	struct timespec64 ts_phase, ts_period;
817 	unsigned long flags;
818 	s64 wf_high, wf_low;
819 	bool pps = false;
820 	int pin;
821 
822 	if (rq->perout.flags & ~(PTP_PEROUT_DUTY_CYCLE |
823 				 PTP_PEROUT_PHASE))
824 		return -EOPNOTSUPP;
825 
826 	pin = ptp_find_pin(phc->clock, PTP_PF_PEROUT, rq->perout.index);
827 	if (pin == -1 || pin >= LAN966X_PHC_PINS_NUM)
828 		return -EINVAL;
829 
830 	if (!on) {
831 		spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
832 		lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_IDLE) |
833 			PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
834 			PTP_PIN_CFG_PIN_SYNC_SET(0),
835 			PTP_PIN_CFG_PIN_ACTION |
836 			PTP_PIN_CFG_PIN_DOM |
837 			PTP_PIN_CFG_PIN_SYNC,
838 			lan966x, PTP_PIN_CFG(pin));
839 		spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
840 		return 0;
841 	}
842 
843 	if (rq->perout.period.sec == 1 &&
844 	    rq->perout.period.nsec == 0)
845 		pps = true;
846 
847 	if (rq->perout.flags & PTP_PEROUT_PHASE) {
848 		ts_phase.tv_sec = rq->perout.phase.sec;
849 		ts_phase.tv_nsec = rq->perout.phase.nsec;
850 	} else {
851 		ts_phase.tv_sec = rq->perout.start.sec;
852 		ts_phase.tv_nsec = rq->perout.start.nsec;
853 	}
854 
855 	if (ts_phase.tv_sec || (ts_phase.tv_nsec && !pps)) {
856 		dev_warn(lan966x->dev,
857 			 "Absolute time not supported!\n");
858 		return -EINVAL;
859 	}
860 
861 	if (rq->perout.flags & PTP_PEROUT_DUTY_CYCLE) {
862 		struct timespec64 ts_on;
863 
864 		ts_on.tv_sec = rq->perout.on.sec;
865 		ts_on.tv_nsec = rq->perout.on.nsec;
866 
867 		wf_high = timespec64_to_ns(&ts_on);
868 	} else {
869 		wf_high = 5000;
870 	}
871 
872 	if (pps) {
873 		spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
874 		lan_wr(PTP_WF_LOW_PERIOD_PIN_WFL(ts_phase.tv_nsec),
875 		       lan966x, PTP_WF_LOW_PERIOD(pin));
876 		lan_wr(PTP_WF_HIGH_PERIOD_PIN_WFH(wf_high),
877 		       lan966x, PTP_WF_HIGH_PERIOD(pin));
878 		lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_CLOCK) |
879 			PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
880 			PTP_PIN_CFG_PIN_SYNC_SET(3),
881 			PTP_PIN_CFG_PIN_ACTION |
882 			PTP_PIN_CFG_PIN_DOM |
883 			PTP_PIN_CFG_PIN_SYNC,
884 			lan966x, PTP_PIN_CFG(pin));
885 		spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
886 		return 0;
887 	}
888 
889 	ts_period.tv_sec = rq->perout.period.sec;
890 	ts_period.tv_nsec = rq->perout.period.nsec;
891 
892 	wf_low = timespec64_to_ns(&ts_period);
893 	wf_low -= wf_high;
894 
895 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
896 	lan_wr(PTP_WF_LOW_PERIOD_PIN_WFL(wf_low),
897 	       lan966x, PTP_WF_LOW_PERIOD(pin));
898 	lan_wr(PTP_WF_HIGH_PERIOD_PIN_WFH(wf_high),
899 	       lan966x, PTP_WF_HIGH_PERIOD(pin));
900 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_CLOCK) |
901 		PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
902 		PTP_PIN_CFG_PIN_SYNC_SET(0),
903 		PTP_PIN_CFG_PIN_ACTION |
904 		PTP_PIN_CFG_PIN_DOM |
905 		PTP_PIN_CFG_PIN_SYNC,
906 		lan966x, PTP_PIN_CFG(pin));
907 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
908 
909 	return 0;
910 }
911 
912 static int lan966x_ptp_extts(struct ptp_clock_info *ptp,
913 			     struct ptp_clock_request *rq, int on)
914 {
915 	struct lan966x_phc *phc = container_of(ptp, struct lan966x_phc, info);
916 	struct lan966x *lan966x = phc->lan966x;
917 	unsigned long flags;
918 	int pin;
919 	u32 val;
920 
921 	if (lan966x->ptp_ext_irq <= 0)
922 		return -EOPNOTSUPP;
923 
924 	/* Reject requests with unsupported flags */
925 	if (rq->extts.flags & ~(PTP_ENABLE_FEATURE |
926 				PTP_RISING_EDGE |
927 				PTP_STRICT_FLAGS))
928 		return -EOPNOTSUPP;
929 
930 	pin = ptp_find_pin(phc->clock, PTP_PF_EXTTS, rq->extts.index);
931 	if (pin == -1 || pin >= LAN966X_PHC_PINS_NUM)
932 		return -EINVAL;
933 
934 	spin_lock_irqsave(&lan966x->ptp_clock_lock, flags);
935 	lan_rmw(PTP_PIN_CFG_PIN_ACTION_SET(PTP_PIN_ACTION_SAVE) |
936 		PTP_PIN_CFG_PIN_SYNC_SET(on ? 3 : 0) |
937 		PTP_PIN_CFG_PIN_DOM_SET(phc->index) |
938 		PTP_PIN_CFG_PIN_SELECT_SET(pin),
939 		PTP_PIN_CFG_PIN_ACTION |
940 		PTP_PIN_CFG_PIN_SYNC |
941 		PTP_PIN_CFG_PIN_DOM |
942 		PTP_PIN_CFG_PIN_SELECT,
943 		lan966x, PTP_PIN_CFG(pin));
944 
945 	val = lan_rd(lan966x, PTP_PIN_INTR_ENA);
946 	if (on)
947 		val |= BIT(pin);
948 	else
949 		val &= ~BIT(pin);
950 	lan_wr(val, lan966x, PTP_PIN_INTR_ENA);
951 
952 	spin_unlock_irqrestore(&lan966x->ptp_clock_lock, flags);
953 
954 	return 0;
955 }
956 
957 static int lan966x_ptp_enable(struct ptp_clock_info *ptp,
958 			      struct ptp_clock_request *rq, int on)
959 {
960 	switch (rq->type) {
961 	case PTP_CLK_REQ_PEROUT:
962 		return lan966x_ptp_perout(ptp, rq, on);
963 	case PTP_CLK_REQ_EXTTS:
964 		return lan966x_ptp_extts(ptp, rq, on);
965 	default:
966 		return -EOPNOTSUPP;
967 	}
968 
969 	return 0;
970 }
971 
972 static struct ptp_clock_info lan966x_ptp_clock_info = {
973 	.owner		= THIS_MODULE,
974 	.name		= "lan966x ptp",
975 	.max_adj	= 200000,
976 	.gettime64	= lan966x_ptp_gettime64,
977 	.settime64	= lan966x_ptp_settime64,
978 	.adjtime	= lan966x_ptp_adjtime,
979 	.adjfine	= lan966x_ptp_adjfine,
980 	.verify		= lan966x_ptp_verify,
981 	.enable		= lan966x_ptp_enable,
982 	.n_per_out	= LAN966X_PHC_PINS_NUM,
983 	.n_ext_ts	= LAN966X_PHC_PINS_NUM,
984 	.n_pins		= LAN966X_PHC_PINS_NUM,
985 };
986 
987 static int lan966x_ptp_phc_init(struct lan966x *lan966x,
988 				int index,
989 				struct ptp_clock_info *clock_info)
990 {
991 	struct lan966x_phc *phc = &lan966x->phc[index];
992 	struct ptp_pin_desc *p;
993 	int i;
994 
995 	for (i = 0; i < LAN966X_PHC_PINS_NUM; i++) {
996 		p = &phc->pins[i];
997 
998 		snprintf(p->name, sizeof(p->name), "pin%d", i);
999 		p->index = i;
1000 		p->func = PTP_PF_NONE;
1001 	}
1002 
1003 	phc->info = *clock_info;
1004 	phc->info.pin_config = &phc->pins[0];
1005 	phc->clock = ptp_clock_register(&phc->info, lan966x->dev);
1006 	if (IS_ERR(phc->clock))
1007 		return PTR_ERR(phc->clock);
1008 
1009 	phc->index = index;
1010 	phc->lan966x = lan966x;
1011 
1012 	/* PTP Rx stamping is always enabled.  */
1013 	phc->hwtstamp_config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
1014 
1015 	return 0;
1016 }
1017 
1018 int lan966x_ptp_init(struct lan966x *lan966x)
1019 {
1020 	u64 tod_adj = lan966x_ptp_get_nominal_value();
1021 	struct lan966x_port *port;
1022 	int err, i;
1023 
1024 	if (!lan966x->ptp)
1025 		return 0;
1026 
1027 	for (i = 0; i < LAN966X_PHC_COUNT; ++i) {
1028 		err = lan966x_ptp_phc_init(lan966x, i, &lan966x_ptp_clock_info);
1029 		if (err)
1030 			return err;
1031 	}
1032 
1033 	spin_lock_init(&lan966x->ptp_clock_lock);
1034 	spin_lock_init(&lan966x->ptp_ts_id_lock);
1035 	mutex_init(&lan966x->ptp_lock);
1036 
1037 	/* Disable master counters */
1038 	lan_wr(PTP_DOM_CFG_ENA_SET(0), lan966x, PTP_DOM_CFG);
1039 
1040 	/* Configure the nominal TOD increment per clock cycle */
1041 	lan_rmw(PTP_DOM_CFG_CLKCFG_DIS_SET(0x7),
1042 		PTP_DOM_CFG_CLKCFG_DIS,
1043 		lan966x, PTP_DOM_CFG);
1044 
1045 	for (i = 0; i < LAN966X_PHC_COUNT; ++i) {
1046 		lan_wr((u32)tod_adj & 0xFFFFFFFF, lan966x,
1047 		       PTP_CLK_PER_CFG(i, 0));
1048 		lan_wr((u32)(tod_adj >> 32), lan966x,
1049 		       PTP_CLK_PER_CFG(i, 1));
1050 	}
1051 
1052 	lan_rmw(PTP_DOM_CFG_CLKCFG_DIS_SET(0),
1053 		PTP_DOM_CFG_CLKCFG_DIS,
1054 		lan966x, PTP_DOM_CFG);
1055 
1056 	/* Enable master counters */
1057 	lan_wr(PTP_DOM_CFG_ENA_SET(0x7), lan966x, PTP_DOM_CFG);
1058 
1059 	for (i = 0; i < lan966x->num_phys_ports; i++) {
1060 		port = lan966x->ports[i];
1061 		if (!port)
1062 			continue;
1063 
1064 		skb_queue_head_init(&port->tx_skbs);
1065 	}
1066 
1067 	return 0;
1068 }
1069 
1070 void lan966x_ptp_deinit(struct lan966x *lan966x)
1071 {
1072 	struct lan966x_port *port;
1073 	int i;
1074 
1075 	if (!lan966x->ptp)
1076 		return;
1077 
1078 	for (i = 0; i < lan966x->num_phys_ports; i++) {
1079 		port = lan966x->ports[i];
1080 		if (!port)
1081 			continue;
1082 
1083 		skb_queue_purge(&port->tx_skbs);
1084 	}
1085 
1086 	for (i = 0; i < LAN966X_PHC_COUNT; ++i)
1087 		ptp_clock_unregister(lan966x->phc[i].clock);
1088 }
1089 
1090 void lan966x_ptp_rxtstamp(struct lan966x *lan966x, struct sk_buff *skb,
1091 			  u64 timestamp)
1092 {
1093 	struct skb_shared_hwtstamps *shhwtstamps;
1094 	struct lan966x_phc *phc;
1095 	struct timespec64 ts;
1096 	u64 full_ts_in_ns;
1097 
1098 	if (!lan966x->ptp)
1099 		return;
1100 
1101 	phc = &lan966x->phc[LAN966X_PHC_PORT];
1102 	lan966x_ptp_gettime64(&phc->info, &ts);
1103 
1104 	/* Drop the sub-ns precision */
1105 	timestamp = timestamp >> 2;
1106 	if (ts.tv_nsec < timestamp)
1107 		ts.tv_sec--;
1108 	ts.tv_nsec = timestamp;
1109 	full_ts_in_ns = ktime_set(ts.tv_sec, ts.tv_nsec);
1110 
1111 	shhwtstamps = skb_hwtstamps(skb);
1112 	shhwtstamps->hwtstamp = full_ts_in_ns;
1113 }
1114 
1115 u32 lan966x_ptp_get_period_ps(void)
1116 {
1117 	/* This represents the system clock period in picoseconds */
1118 	return 15125;
1119 }
1120