xref: /linux/drivers/net/dsa/microchip/ksz_ptp.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Microchip KSZ PTP Implementation
3  *
4  * Copyright (C) 2020 ARRI Lighting
5  * Copyright (C) 2022 Microchip Technology Inc.
6  */
7 
8 #include <linux/dsa/ksz_common.h>
9 #include <linux/irq.h>
10 #include <linux/irqdomain.h>
11 #include <linux/kernel.h>
12 #include <linux/ptp_classify.h>
13 #include <linux/ptp_clock_kernel.h>
14 
15 #include "ksz_common.h"
16 #include "ksz_ptp.h"
17 #include "ksz_ptp_reg.h"
18 
19 #define ptp_caps_to_data(d) container_of((d), struct ksz_ptp_data, caps)
20 #define ptp_data_to_ksz_dev(d) container_of((d), struct ksz_device, ptp_data)
21 #define work_to_xmit_work(w) \
22 		container_of((w), struct ksz_deferred_xmit_work, work)
23 
24 /* Sub-nanoseconds-adj,max * sub-nanoseconds / 40ns * 1ns
25  * = (2^30-1) * (2 ^ 32) / 40 ns * 1 ns = 6249999
26  */
27 #define KSZ_MAX_DRIFT_CORR 6249999
28 #define KSZ_MAX_PULSE_WIDTH 125000000LL
29 
30 #define KSZ_PTP_INC_NS 40ULL  /* HW clock is incremented every 40 ns (by 40) */
31 #define KSZ_PTP_SUBNS_BITS 32
32 
33 #define KSZ_PTP_INT_START 13
34 
35 static int ksz_ptp_tou_gpio(struct ksz_device *dev)
36 {
37 	int ret;
38 
39 	if (!is_lan937x(dev))
40 		return 0;
41 
42 	ret = ksz_rmw32(dev, REG_PTP_CTRL_STAT__4, GPIO_OUT,
43 			GPIO_OUT);
44 	if (ret)
45 		return ret;
46 
47 	ret = ksz_rmw32(dev, REG_SW_GLOBAL_LED_OVR__4, LED_OVR_1 | LED_OVR_2,
48 			LED_OVR_1 | LED_OVR_2);
49 	if (ret)
50 		return ret;
51 
52 	return ksz_rmw32(dev, REG_SW_GLOBAL_LED_SRC__4,
53 			 LED_SRC_PTP_GPIO_1 | LED_SRC_PTP_GPIO_2,
54 			 LED_SRC_PTP_GPIO_1 | LED_SRC_PTP_GPIO_2);
55 }
56 
57 static int ksz_ptp_tou_reset(struct ksz_device *dev, u8 unit)
58 {
59 	u32 data;
60 	int ret;
61 
62 	/* Reset trigger unit (clears TRIGGER_EN, but not GPIOSTATx) */
63 	ret = ksz_rmw32(dev, REG_PTP_CTRL_STAT__4, TRIG_RESET, TRIG_RESET);
64 
65 	data = FIELD_PREP(TRIG_DONE_M, BIT(unit));
66 	ret = ksz_write32(dev, REG_PTP_TRIG_STATUS__4, data);
67 	if (ret)
68 		return ret;
69 
70 	data = FIELD_PREP(TRIG_INT_M, BIT(unit));
71 	ret = ksz_write32(dev, REG_PTP_INT_STATUS__4, data);
72 	if (ret)
73 		return ret;
74 
75 	/* Clear reset and set GPIO direction */
76 	return ksz_rmw32(dev, REG_PTP_CTRL_STAT__4, (TRIG_RESET | TRIG_ENABLE),
77 			 0);
78 }
79 
80 static int ksz_ptp_tou_pulse_verify(u64 pulse_ns)
81 {
82 	u32 data;
83 
84 	if (pulse_ns & 0x3)
85 		return -EINVAL;
86 
87 	data = (pulse_ns / 8);
88 	if (!FIELD_FIT(TRIG_PULSE_WIDTH_M, data))
89 		return -ERANGE;
90 
91 	return 0;
92 }
93 
94 static int ksz_ptp_tou_target_time_set(struct ksz_device *dev,
95 				       struct timespec64 const *ts)
96 {
97 	int ret;
98 
99 	/* Hardware has only 32 bit */
100 	if ((ts->tv_sec & 0xffffffff) != ts->tv_sec)
101 		return -EINVAL;
102 
103 	ret = ksz_write32(dev, REG_TRIG_TARGET_NANOSEC, ts->tv_nsec);
104 	if (ret)
105 		return ret;
106 
107 	ret = ksz_write32(dev, REG_TRIG_TARGET_SEC, ts->tv_sec);
108 	if (ret)
109 		return ret;
110 
111 	return 0;
112 }
113 
114 static int ksz_ptp_tou_start(struct ksz_device *dev, u8 unit)
115 {
116 	u32 data;
117 	int ret;
118 
119 	ret = ksz_rmw32(dev, REG_PTP_CTRL_STAT__4, TRIG_ENABLE, TRIG_ENABLE);
120 	if (ret)
121 		return ret;
122 
123 	/* Check error flag:
124 	 * - the ACTIVE flag is NOT cleared an error!
125 	 */
126 	ret = ksz_read32(dev, REG_PTP_TRIG_STATUS__4, &data);
127 	if (ret)
128 		return ret;
129 
130 	if (FIELD_GET(TRIG_ERROR_M, data) & (1 << unit)) {
131 		dev_err(dev->dev, "%s: Trigger unit%d error!\n", __func__,
132 			unit);
133 		ret = -EIO;
134 		/* Unit will be reset on next access */
135 		return ret;
136 	}
137 
138 	return 0;
139 }
140 
141 static int ksz_ptp_configure_perout(struct ksz_device *dev,
142 				    u32 cycle_width_ns, u32 pulse_width_ns,
143 				    struct timespec64 const *target_time,
144 				    u8 index)
145 {
146 	u32 data;
147 	int ret;
148 
149 	data = FIELD_PREP(TRIG_NOTIFY, 1) |
150 		FIELD_PREP(TRIG_GPO_M, index) |
151 		FIELD_PREP(TRIG_PATTERN_M, TRIG_POS_PERIOD);
152 	ret = ksz_write32(dev, REG_TRIG_CTRL__4, data);
153 	if (ret)
154 		return ret;
155 
156 	ret = ksz_write32(dev, REG_TRIG_CYCLE_WIDTH, cycle_width_ns);
157 	if (ret)
158 		return ret;
159 
160 	/* Set cycle count 0 - Infinite */
161 	ret = ksz_rmw32(dev, REG_TRIG_CYCLE_CNT, TRIG_CYCLE_CNT_M, 0);
162 	if (ret)
163 		return ret;
164 
165 	data = (pulse_width_ns / 8);
166 	ret = ksz_write32(dev, REG_TRIG_PULSE_WIDTH__4, data);
167 	if (ret)
168 		return ret;
169 
170 	ret = ksz_ptp_tou_target_time_set(dev, target_time);
171 	if (ret)
172 		return ret;
173 
174 	return 0;
175 }
176 
177 static int ksz_ptp_enable_perout(struct ksz_device *dev,
178 				 struct ptp_perout_request const *request,
179 				 int on)
180 {
181 	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
182 	u64 req_pulse_width_ns;
183 	u64 cycle_width_ns;
184 	u64 pulse_width_ns;
185 	int pin = 0;
186 	u32 data32;
187 	int ret;
188 
189 	if (request->flags & ~PTP_PEROUT_DUTY_CYCLE)
190 		return -EOPNOTSUPP;
191 
192 	if (ptp_data->tou_mode != KSZ_PTP_TOU_PEROUT &&
193 	    ptp_data->tou_mode != KSZ_PTP_TOU_IDLE)
194 		return -EBUSY;
195 
196 	pin = ptp_find_pin(ptp_data->clock, PTP_PF_PEROUT, request->index);
197 	if (pin < 0)
198 		return -EINVAL;
199 
200 	data32 = FIELD_PREP(PTP_GPIO_INDEX, pin) |
201 		 FIELD_PREP(PTP_TOU_INDEX, request->index);
202 	ret = ksz_rmw32(dev, REG_PTP_UNIT_INDEX__4,
203 			PTP_GPIO_INDEX | PTP_TOU_INDEX, data32);
204 	if (ret)
205 		return ret;
206 
207 	ret = ksz_ptp_tou_reset(dev, request->index);
208 	if (ret)
209 		return ret;
210 
211 	if (!on) {
212 		ptp_data->tou_mode = KSZ_PTP_TOU_IDLE;
213 		return 0;
214 	}
215 
216 	ptp_data->perout_target_time_first.tv_sec  = request->start.sec;
217 	ptp_data->perout_target_time_first.tv_nsec = request->start.nsec;
218 
219 	ptp_data->perout_period.tv_sec = request->period.sec;
220 	ptp_data->perout_period.tv_nsec = request->period.nsec;
221 
222 	cycle_width_ns = timespec64_to_ns(&ptp_data->perout_period);
223 	if ((cycle_width_ns & TRIG_CYCLE_WIDTH_M) != cycle_width_ns)
224 		return -EINVAL;
225 
226 	if (request->flags & PTP_PEROUT_DUTY_CYCLE) {
227 		pulse_width_ns = request->on.sec * NSEC_PER_SEC +
228 			request->on.nsec;
229 	} else {
230 		/* Use a duty cycle of 50%. Maximum pulse width supported by the
231 		 * hardware is a little bit more than 125 ms.
232 		 */
233 		req_pulse_width_ns = (request->period.sec * NSEC_PER_SEC +
234 				      request->period.nsec) / 2;
235 		pulse_width_ns = min_t(u64, req_pulse_width_ns,
236 				       KSZ_MAX_PULSE_WIDTH);
237 	}
238 
239 	ret = ksz_ptp_tou_pulse_verify(pulse_width_ns);
240 	if (ret)
241 		return ret;
242 
243 	ret = ksz_ptp_configure_perout(dev, cycle_width_ns, pulse_width_ns,
244 				       &ptp_data->perout_target_time_first,
245 				       pin);
246 	if (ret)
247 		return ret;
248 
249 	ret = ksz_ptp_tou_gpio(dev);
250 	if (ret)
251 		return ret;
252 
253 	ret = ksz_ptp_tou_start(dev, request->index);
254 	if (ret)
255 		return ret;
256 
257 	ptp_data->tou_mode = KSZ_PTP_TOU_PEROUT;
258 
259 	return 0;
260 }
261 
262 static int ksz_ptp_enable_mode(struct ksz_device *dev)
263 {
264 	struct ksz_tagger_data *tagger_data = ksz_tagger_data(dev->ds);
265 	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
266 	struct ksz_port *prt;
267 	struct dsa_port *dp;
268 	bool tag_en = false;
269 	int ret;
270 
271 	dsa_switch_for_each_user_port(dp, dev->ds) {
272 		prt = &dev->ports[dp->index];
273 		if (prt->hwts_tx_en || prt->hwts_rx_en) {
274 			tag_en = true;
275 			break;
276 		}
277 	}
278 
279 	if (tag_en) {
280 		ret = ptp_schedule_worker(ptp_data->clock, 0);
281 		if (ret)
282 			return ret;
283 	} else {
284 		ptp_cancel_worker_sync(ptp_data->clock);
285 	}
286 
287 	tagger_data->hwtstamp_set_state(dev->ds, tag_en);
288 
289 	return ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_ENABLE,
290 			 tag_en ? PTP_ENABLE : 0);
291 }
292 
293 /* The function is return back the capability of timestamping feature when
294  * requested through ethtool -T <interface> utility
295  */
296 int ksz_get_ts_info(struct dsa_switch *ds, int port, struct ethtool_ts_info *ts)
297 {
298 	struct ksz_device *dev = ds->priv;
299 	struct ksz_ptp_data *ptp_data;
300 
301 	ptp_data = &dev->ptp_data;
302 
303 	if (!ptp_data->clock)
304 		return -ENODEV;
305 
306 	ts->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
307 			      SOF_TIMESTAMPING_RX_HARDWARE |
308 			      SOF_TIMESTAMPING_RAW_HARDWARE;
309 
310 	ts->tx_types = BIT(HWTSTAMP_TX_OFF) | BIT(HWTSTAMP_TX_ONESTEP_P2P);
311 
312 	if (is_lan937x(dev))
313 		ts->tx_types |= BIT(HWTSTAMP_TX_ON);
314 
315 	ts->rx_filters = BIT(HWTSTAMP_FILTER_NONE) |
316 			 BIT(HWTSTAMP_FILTER_PTP_V2_L4_EVENT) |
317 			 BIT(HWTSTAMP_FILTER_PTP_V2_L2_EVENT) |
318 			 BIT(HWTSTAMP_FILTER_PTP_V2_EVENT);
319 
320 	ts->phc_index = ptp_clock_index(ptp_data->clock);
321 
322 	return 0;
323 }
324 
325 int ksz_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr)
326 {
327 	struct ksz_device *dev = ds->priv;
328 	struct hwtstamp_config *config;
329 	struct ksz_port *prt;
330 
331 	prt = &dev->ports[port];
332 	config = &prt->tstamp_config;
333 
334 	return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ?
335 		-EFAULT : 0;
336 }
337 
338 static int ksz_set_hwtstamp_config(struct ksz_device *dev,
339 				   struct ksz_port *prt,
340 				   struct hwtstamp_config *config)
341 {
342 	int ret;
343 
344 	if (config->flags)
345 		return -EINVAL;
346 
347 	switch (config->tx_type) {
348 	case HWTSTAMP_TX_OFF:
349 		prt->ptpmsg_irq[KSZ_SYNC_MSG].ts_en  = false;
350 		prt->ptpmsg_irq[KSZ_XDREQ_MSG].ts_en = false;
351 		prt->ptpmsg_irq[KSZ_PDRES_MSG].ts_en = false;
352 		prt->hwts_tx_en = false;
353 		break;
354 	case HWTSTAMP_TX_ONESTEP_P2P:
355 		prt->ptpmsg_irq[KSZ_SYNC_MSG].ts_en  = false;
356 		prt->ptpmsg_irq[KSZ_XDREQ_MSG].ts_en = true;
357 		prt->ptpmsg_irq[KSZ_PDRES_MSG].ts_en = false;
358 		prt->hwts_tx_en = true;
359 
360 		ret = ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_1STEP, PTP_1STEP);
361 		if (ret)
362 			return ret;
363 
364 		break;
365 	case HWTSTAMP_TX_ON:
366 		if (!is_lan937x(dev))
367 			return -ERANGE;
368 
369 		prt->ptpmsg_irq[KSZ_SYNC_MSG].ts_en  = true;
370 		prt->ptpmsg_irq[KSZ_XDREQ_MSG].ts_en = true;
371 		prt->ptpmsg_irq[KSZ_PDRES_MSG].ts_en = true;
372 		prt->hwts_tx_en = true;
373 
374 		ret = ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_1STEP, 0);
375 		if (ret)
376 			return ret;
377 
378 		break;
379 	default:
380 		return -ERANGE;
381 	}
382 
383 	switch (config->rx_filter) {
384 	case HWTSTAMP_FILTER_NONE:
385 		prt->hwts_rx_en = false;
386 		break;
387 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
388 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
389 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
390 		prt->hwts_rx_en = true;
391 		break;
392 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
393 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
394 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;
395 		prt->hwts_rx_en = true;
396 		break;
397 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
398 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
399 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
400 		prt->hwts_rx_en = true;
401 		break;
402 	default:
403 		config->rx_filter = HWTSTAMP_FILTER_NONE;
404 		return -ERANGE;
405 	}
406 
407 	return ksz_ptp_enable_mode(dev);
408 }
409 
410 int ksz_hwtstamp_set(struct dsa_switch *ds, int port, struct ifreq *ifr)
411 {
412 	struct ksz_device *dev = ds->priv;
413 	struct hwtstamp_config config;
414 	struct ksz_port *prt;
415 	int ret;
416 
417 	prt = &dev->ports[port];
418 
419 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
420 		return -EFAULT;
421 
422 	ret = ksz_set_hwtstamp_config(dev, prt, &config);
423 	if (ret)
424 		return ret;
425 
426 	memcpy(&prt->tstamp_config, &config, sizeof(config));
427 
428 	if (copy_to_user(ifr->ifr_data, &config, sizeof(config)))
429 		return -EFAULT;
430 
431 	return 0;
432 }
433 
434 static ktime_t ksz_tstamp_reconstruct(struct ksz_device *dev, ktime_t tstamp)
435 {
436 	struct timespec64 ptp_clock_time;
437 	struct ksz_ptp_data *ptp_data;
438 	struct timespec64 diff;
439 	struct timespec64 ts;
440 
441 	ptp_data = &dev->ptp_data;
442 	ts = ktime_to_timespec64(tstamp);
443 
444 	spin_lock_bh(&ptp_data->clock_lock);
445 	ptp_clock_time = ptp_data->clock_time;
446 	spin_unlock_bh(&ptp_data->clock_lock);
447 
448 	/* calculate full time from partial time stamp */
449 	ts.tv_sec = (ptp_clock_time.tv_sec & ~3) | ts.tv_sec;
450 
451 	/* find nearest possible point in time */
452 	diff = timespec64_sub(ts, ptp_clock_time);
453 	if (diff.tv_sec > 2)
454 		ts.tv_sec -= 4;
455 	else if (diff.tv_sec < -2)
456 		ts.tv_sec += 4;
457 
458 	return timespec64_to_ktime(ts);
459 }
460 
461 bool ksz_port_rxtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb,
462 		       unsigned int type)
463 {
464 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
465 	struct ksz_device *dev = ds->priv;
466 	struct ptp_header *ptp_hdr;
467 	struct ksz_port *prt;
468 	u8 ptp_msg_type;
469 	ktime_t tstamp;
470 	s64 correction;
471 
472 	prt = &dev->ports[port];
473 
474 	tstamp = KSZ_SKB_CB(skb)->tstamp;
475 	memset(hwtstamps, 0, sizeof(*hwtstamps));
476 	hwtstamps->hwtstamp = ksz_tstamp_reconstruct(dev, tstamp);
477 
478 	if (prt->tstamp_config.tx_type != HWTSTAMP_TX_ONESTEP_P2P)
479 		goto out;
480 
481 	ptp_hdr = ptp_parse_header(skb, type);
482 	if (!ptp_hdr)
483 		goto out;
484 
485 	ptp_msg_type = ptp_get_msgtype(ptp_hdr, type);
486 	if (ptp_msg_type != PTP_MSGTYPE_PDELAY_REQ)
487 		goto out;
488 
489 	/* Only subtract the partial time stamp from the correction field.  When
490 	 * the hardware adds the egress time stamp to the correction field of
491 	 * the PDelay_Resp message on tx, also only the partial time stamp will
492 	 * be added.
493 	 */
494 	correction = (s64)get_unaligned_be64(&ptp_hdr->correction);
495 	correction -= ktime_to_ns(tstamp) << 16;
496 
497 	ptp_header_update_correction(skb, type, ptp_hdr, correction);
498 
499 out:
500 	return false;
501 }
502 
503 void ksz_port_txtstamp(struct dsa_switch *ds, int port, struct sk_buff *skb)
504 {
505 	struct ksz_device *dev = ds->priv;
506 	struct ptp_header *hdr;
507 	struct sk_buff *clone;
508 	struct ksz_port *prt;
509 	unsigned int type;
510 	u8 ptp_msg_type;
511 
512 	prt = &dev->ports[port];
513 
514 	if (!prt->hwts_tx_en)
515 		return;
516 
517 	type = ptp_classify_raw(skb);
518 	if (type == PTP_CLASS_NONE)
519 		return;
520 
521 	hdr = ptp_parse_header(skb, type);
522 	if (!hdr)
523 		return;
524 
525 	ptp_msg_type = ptp_get_msgtype(hdr, type);
526 
527 	switch (ptp_msg_type) {
528 	case PTP_MSGTYPE_SYNC:
529 		if (prt->tstamp_config.tx_type == HWTSTAMP_TX_ONESTEP_P2P)
530 			return;
531 		break;
532 	case PTP_MSGTYPE_PDELAY_REQ:
533 		break;
534 	case PTP_MSGTYPE_PDELAY_RESP:
535 		if (prt->tstamp_config.tx_type == HWTSTAMP_TX_ONESTEP_P2P) {
536 			KSZ_SKB_CB(skb)->ptp_type = type;
537 			KSZ_SKB_CB(skb)->update_correction = true;
538 			return;
539 		}
540 		break;
541 
542 	default:
543 		return;
544 	}
545 
546 	clone = skb_clone_sk(skb);
547 	if (!clone)
548 		return;
549 
550 	/* caching the value to be used in tag_ksz.c */
551 	KSZ_SKB_CB(skb)->clone = clone;
552 }
553 
554 static void ksz_ptp_txtstamp_skb(struct ksz_device *dev,
555 				 struct ksz_port *prt, struct sk_buff *skb)
556 {
557 	struct skb_shared_hwtstamps hwtstamps = {};
558 	int ret;
559 
560 	/* timeout must include DSA conduit to transmit data, tstamp latency,
561 	 * IRQ latency and time for reading the time stamp.
562 	 */
563 	ret = wait_for_completion_timeout(&prt->tstamp_msg_comp,
564 					  msecs_to_jiffies(100));
565 	if (!ret)
566 		return;
567 
568 	hwtstamps.hwtstamp = prt->tstamp_msg;
569 	skb_complete_tx_timestamp(skb, &hwtstamps);
570 }
571 
572 void ksz_port_deferred_xmit(struct kthread_work *work)
573 {
574 	struct ksz_deferred_xmit_work *xmit_work = work_to_xmit_work(work);
575 	struct sk_buff *clone, *skb = xmit_work->skb;
576 	struct dsa_switch *ds = xmit_work->dp->ds;
577 	struct ksz_device *dev = ds->priv;
578 	struct ksz_port *prt;
579 
580 	prt = &dev->ports[xmit_work->dp->index];
581 
582 	clone = KSZ_SKB_CB(skb)->clone;
583 
584 	skb_shinfo(clone)->tx_flags |= SKBTX_IN_PROGRESS;
585 
586 	reinit_completion(&prt->tstamp_msg_comp);
587 
588 	dsa_enqueue_skb(skb, skb->dev);
589 
590 	ksz_ptp_txtstamp_skb(dev, prt, clone);
591 
592 	kfree(xmit_work);
593 }
594 
595 static int _ksz_ptp_gettime(struct ksz_device *dev, struct timespec64 *ts)
596 {
597 	u32 nanoseconds;
598 	u32 seconds;
599 	u8 phase;
600 	int ret;
601 
602 	/* Copy current PTP clock into shadow registers and read */
603 	ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_READ_TIME, PTP_READ_TIME);
604 	if (ret)
605 		return ret;
606 
607 	ret = ksz_read8(dev, REG_PTP_RTC_SUB_NANOSEC__2, &phase);
608 	if (ret)
609 		return ret;
610 
611 	ret = ksz_read32(dev, REG_PTP_RTC_NANOSEC, &nanoseconds);
612 	if (ret)
613 		return ret;
614 
615 	ret = ksz_read32(dev, REG_PTP_RTC_SEC, &seconds);
616 	if (ret)
617 		return ret;
618 
619 	ts->tv_sec = seconds;
620 	ts->tv_nsec = nanoseconds + phase * 8;
621 
622 	return 0;
623 }
624 
625 static int ksz_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
626 {
627 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
628 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
629 	int ret;
630 
631 	mutex_lock(&ptp_data->lock);
632 	ret = _ksz_ptp_gettime(dev, ts);
633 	mutex_unlock(&ptp_data->lock);
634 
635 	return ret;
636 }
637 
638 static int ksz_ptp_restart_perout(struct ksz_device *dev)
639 {
640 	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
641 	s64 now_ns, first_ns, period_ns, next_ns;
642 	struct ptp_perout_request request;
643 	struct timespec64 next;
644 	struct timespec64 now;
645 	unsigned int count;
646 	int ret;
647 
648 	dev_info(dev->dev, "Restarting periodic output signal\n");
649 
650 	ret = _ksz_ptp_gettime(dev, &now);
651 	if (ret)
652 		return ret;
653 
654 	now_ns = timespec64_to_ns(&now);
655 	first_ns = timespec64_to_ns(&ptp_data->perout_target_time_first);
656 
657 	/* Calculate next perout event based on start time and period */
658 	period_ns = timespec64_to_ns(&ptp_data->perout_period);
659 
660 	if (first_ns < now_ns) {
661 		count = div_u64(now_ns - first_ns, period_ns);
662 		next_ns = first_ns + count * period_ns;
663 	} else {
664 		next_ns = first_ns;
665 	}
666 
667 	/* Ensure 100 ms guard time prior next event */
668 	while (next_ns < now_ns + 100000000)
669 		next_ns += period_ns;
670 
671 	/* Restart periodic output signal */
672 	next = ns_to_timespec64(next_ns);
673 	request.start.sec  = next.tv_sec;
674 	request.start.nsec = next.tv_nsec;
675 	request.period.sec  = ptp_data->perout_period.tv_sec;
676 	request.period.nsec = ptp_data->perout_period.tv_nsec;
677 	request.index = 0;
678 	request.flags = 0;
679 
680 	return ksz_ptp_enable_perout(dev, &request, 1);
681 }
682 
683 static int ksz_ptp_settime(struct ptp_clock_info *ptp,
684 			   const struct timespec64 *ts)
685 {
686 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
687 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
688 	int ret;
689 
690 	mutex_lock(&ptp_data->lock);
691 
692 	/* Write to shadow registers and Load PTP clock */
693 	ret = ksz_write16(dev, REG_PTP_RTC_SUB_NANOSEC__2, PTP_RTC_0NS);
694 	if (ret)
695 		goto unlock;
696 
697 	ret = ksz_write32(dev, REG_PTP_RTC_NANOSEC, ts->tv_nsec);
698 	if (ret)
699 		goto unlock;
700 
701 	ret = ksz_write32(dev, REG_PTP_RTC_SEC, ts->tv_sec);
702 	if (ret)
703 		goto unlock;
704 
705 	ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_LOAD_TIME, PTP_LOAD_TIME);
706 	if (ret)
707 		goto unlock;
708 
709 	switch (ptp_data->tou_mode) {
710 	case KSZ_PTP_TOU_IDLE:
711 		break;
712 
713 	case KSZ_PTP_TOU_PEROUT:
714 		ret = ksz_ptp_restart_perout(dev);
715 		if (ret)
716 			goto unlock;
717 
718 		break;
719 	}
720 
721 	spin_lock_bh(&ptp_data->clock_lock);
722 	ptp_data->clock_time = *ts;
723 	spin_unlock_bh(&ptp_data->clock_lock);
724 
725 unlock:
726 	mutex_unlock(&ptp_data->lock);
727 
728 	return ret;
729 }
730 
731 static int ksz_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
732 {
733 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
734 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
735 	u64 base, adj;
736 	bool negative;
737 	u32 data32;
738 	int ret;
739 
740 	mutex_lock(&ptp_data->lock);
741 
742 	if (scaled_ppm) {
743 		base = KSZ_PTP_INC_NS << KSZ_PTP_SUBNS_BITS;
744 		negative = diff_by_scaled_ppm(base, scaled_ppm, &adj);
745 
746 		data32 = (u32)adj;
747 		data32 &= PTP_SUBNANOSEC_M;
748 		if (!negative)
749 			data32 |= PTP_RATE_DIR;
750 
751 		ret = ksz_write32(dev, REG_PTP_SUBNANOSEC_RATE, data32);
752 		if (ret)
753 			goto unlock;
754 
755 		ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ADJ_ENABLE,
756 				PTP_CLK_ADJ_ENABLE);
757 		if (ret)
758 			goto unlock;
759 	} else {
760 		ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ADJ_ENABLE, 0);
761 		if (ret)
762 			goto unlock;
763 	}
764 
765 unlock:
766 	mutex_unlock(&ptp_data->lock);
767 	return ret;
768 }
769 
770 static int ksz_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
771 {
772 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
773 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
774 	struct timespec64 delta64 = ns_to_timespec64(delta);
775 	s32 sec, nsec;
776 	u16 data16;
777 	int ret;
778 
779 	mutex_lock(&ptp_data->lock);
780 
781 	/* do not use ns_to_timespec64(),
782 	 * both sec and nsec are subtracted by hw
783 	 */
784 	sec = div_s64_rem(delta, NSEC_PER_SEC, &nsec);
785 
786 	ret = ksz_write32(dev, REG_PTP_RTC_NANOSEC, abs(nsec));
787 	if (ret)
788 		goto unlock;
789 
790 	ret = ksz_write32(dev, REG_PTP_RTC_SEC, abs(sec));
791 	if (ret)
792 		goto unlock;
793 
794 	ret = ksz_read16(dev, REG_PTP_CLK_CTRL, &data16);
795 	if (ret)
796 		goto unlock;
797 
798 	data16 |= PTP_STEP_ADJ;
799 
800 	/* PTP_STEP_DIR -- 0: subtract, 1: add */
801 	if (delta < 0)
802 		data16 &= ~PTP_STEP_DIR;
803 	else
804 		data16 |= PTP_STEP_DIR;
805 
806 	ret = ksz_write16(dev, REG_PTP_CLK_CTRL, data16);
807 	if (ret)
808 		goto unlock;
809 
810 	switch (ptp_data->tou_mode) {
811 	case KSZ_PTP_TOU_IDLE:
812 		break;
813 
814 	case KSZ_PTP_TOU_PEROUT:
815 		ret = ksz_ptp_restart_perout(dev);
816 		if (ret)
817 			goto unlock;
818 
819 		break;
820 	}
821 
822 	spin_lock_bh(&ptp_data->clock_lock);
823 	ptp_data->clock_time = timespec64_add(ptp_data->clock_time, delta64);
824 	spin_unlock_bh(&ptp_data->clock_lock);
825 
826 unlock:
827 	mutex_unlock(&ptp_data->lock);
828 	return ret;
829 }
830 
831 static int ksz_ptp_enable(struct ptp_clock_info *ptp,
832 			  struct ptp_clock_request *req, int on)
833 {
834 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
835 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
836 	int ret;
837 
838 	switch (req->type) {
839 	case PTP_CLK_REQ_PEROUT:
840 		mutex_lock(&ptp_data->lock);
841 		ret = ksz_ptp_enable_perout(dev, &req->perout, on);
842 		mutex_unlock(&ptp_data->lock);
843 		break;
844 	default:
845 		return -EOPNOTSUPP;
846 	}
847 
848 	return ret;
849 }
850 
851 static int ksz_ptp_verify_pin(struct ptp_clock_info *ptp, unsigned int pin,
852 			      enum ptp_pin_function func, unsigned int chan)
853 {
854 	int ret = 0;
855 
856 	switch (func) {
857 	case PTP_PF_NONE:
858 	case PTP_PF_PEROUT:
859 		break;
860 	default:
861 		ret = -1;
862 		break;
863 	}
864 
865 	return ret;
866 }
867 
868 /*  Function is pointer to the do_aux_work in the ptp_clock capability */
869 static long ksz_ptp_do_aux_work(struct ptp_clock_info *ptp)
870 {
871 	struct ksz_ptp_data *ptp_data = ptp_caps_to_data(ptp);
872 	struct ksz_device *dev = ptp_data_to_ksz_dev(ptp_data);
873 	struct timespec64 ts;
874 	int ret;
875 
876 	mutex_lock(&ptp_data->lock);
877 	ret = _ksz_ptp_gettime(dev, &ts);
878 	if (ret)
879 		goto out;
880 
881 	spin_lock_bh(&ptp_data->clock_lock);
882 	ptp_data->clock_time = ts;
883 	spin_unlock_bh(&ptp_data->clock_lock);
884 
885 out:
886 	mutex_unlock(&ptp_data->lock);
887 
888 	return HZ;  /* reschedule in 1 second */
889 }
890 
891 static int ksz_ptp_start_clock(struct ksz_device *dev)
892 {
893 	struct ksz_ptp_data *ptp_data = &dev->ptp_data;
894 	int ret;
895 
896 	ret = ksz_rmw16(dev, REG_PTP_CLK_CTRL, PTP_CLK_ENABLE, PTP_CLK_ENABLE);
897 	if (ret)
898 		return ret;
899 
900 	ptp_data->clock_time.tv_sec = 0;
901 	ptp_data->clock_time.tv_nsec = 0;
902 
903 	return 0;
904 }
905 
906 int ksz_ptp_clock_register(struct dsa_switch *ds)
907 {
908 	struct ksz_device *dev = ds->priv;
909 	struct ksz_ptp_data *ptp_data;
910 	int ret;
911 	u8 i;
912 
913 	ptp_data = &dev->ptp_data;
914 	mutex_init(&ptp_data->lock);
915 	spin_lock_init(&ptp_data->clock_lock);
916 
917 	ptp_data->caps.owner		= THIS_MODULE;
918 	snprintf(ptp_data->caps.name, 16, "Microchip Clock");
919 	ptp_data->caps.max_adj		= KSZ_MAX_DRIFT_CORR;
920 	ptp_data->caps.gettime64	= ksz_ptp_gettime;
921 	ptp_data->caps.settime64	= ksz_ptp_settime;
922 	ptp_data->caps.adjfine		= ksz_ptp_adjfine;
923 	ptp_data->caps.adjtime		= ksz_ptp_adjtime;
924 	ptp_data->caps.do_aux_work	= ksz_ptp_do_aux_work;
925 	ptp_data->caps.enable		= ksz_ptp_enable;
926 	ptp_data->caps.verify		= ksz_ptp_verify_pin;
927 	ptp_data->caps.n_pins		= KSZ_PTP_N_GPIO;
928 	ptp_data->caps.n_per_out	= 3;
929 
930 	ret = ksz_ptp_start_clock(dev);
931 	if (ret)
932 		return ret;
933 
934 	for (i = 0; i < KSZ_PTP_N_GPIO; i++) {
935 		struct ptp_pin_desc *ptp_pin = &ptp_data->pin_config[i];
936 
937 		snprintf(ptp_pin->name,
938 			 sizeof(ptp_pin->name), "ksz_ptp_pin_%02d", i);
939 		ptp_pin->index = i;
940 		ptp_pin->func = PTP_PF_NONE;
941 	}
942 
943 	ptp_data->caps.pin_config = ptp_data->pin_config;
944 
945 	/* Currently only P2P mode is supported. When 802_1AS bit is set, it
946 	 * forwards all PTP packets to host port and none to other ports.
947 	 */
948 	ret = ksz_rmw16(dev, REG_PTP_MSG_CONF1, PTP_TC_P2P | PTP_802_1AS,
949 			PTP_TC_P2P | PTP_802_1AS);
950 	if (ret)
951 		return ret;
952 
953 	ptp_data->clock = ptp_clock_register(&ptp_data->caps, dev->dev);
954 	if (IS_ERR_OR_NULL(ptp_data->clock))
955 		return PTR_ERR(ptp_data->clock);
956 
957 	return 0;
958 }
959 
960 void ksz_ptp_clock_unregister(struct dsa_switch *ds)
961 {
962 	struct ksz_device *dev = ds->priv;
963 	struct ksz_ptp_data *ptp_data;
964 
965 	ptp_data = &dev->ptp_data;
966 
967 	if (ptp_data->clock)
968 		ptp_clock_unregister(ptp_data->clock);
969 }
970 
971 static irqreturn_t ksz_ptp_msg_thread_fn(int irq, void *dev_id)
972 {
973 	struct ksz_ptp_irq *ptpmsg_irq = dev_id;
974 	struct ksz_device *dev;
975 	struct ksz_port *port;
976 	u32 tstamp_raw;
977 	ktime_t tstamp;
978 	int ret;
979 
980 	port = ptpmsg_irq->port;
981 	dev = port->ksz_dev;
982 
983 	if (ptpmsg_irq->ts_en) {
984 		ret = ksz_read32(dev, ptpmsg_irq->ts_reg, &tstamp_raw);
985 		if (ret)
986 			return IRQ_NONE;
987 
988 		tstamp = ksz_decode_tstamp(tstamp_raw);
989 
990 		port->tstamp_msg = ksz_tstamp_reconstruct(dev, tstamp);
991 
992 		complete(&port->tstamp_msg_comp);
993 	}
994 
995 	return IRQ_HANDLED;
996 }
997 
998 static irqreturn_t ksz_ptp_irq_thread_fn(int irq, void *dev_id)
999 {
1000 	struct ksz_irq *ptpirq = dev_id;
1001 	unsigned int nhandled = 0;
1002 	struct ksz_device *dev;
1003 	unsigned int sub_irq;
1004 	u16 data;
1005 	int ret;
1006 	u8 n;
1007 
1008 	dev = ptpirq->dev;
1009 
1010 	ret = ksz_read16(dev, ptpirq->reg_status, &data);
1011 	if (ret)
1012 		goto out;
1013 
1014 	/* Clear the interrupts W1C */
1015 	ret = ksz_write16(dev, ptpirq->reg_status, data);
1016 	if (ret)
1017 		return IRQ_NONE;
1018 
1019 	for (n = 0; n < ptpirq->nirqs; ++n) {
1020 		if (data & BIT(n + KSZ_PTP_INT_START)) {
1021 			sub_irq = irq_find_mapping(ptpirq->domain, n);
1022 			handle_nested_irq(sub_irq);
1023 			++nhandled;
1024 		}
1025 	}
1026 
1027 out:
1028 	return (nhandled > 0 ? IRQ_HANDLED : IRQ_NONE);
1029 }
1030 
1031 static void ksz_ptp_irq_mask(struct irq_data *d)
1032 {
1033 	struct ksz_irq *kirq = irq_data_get_irq_chip_data(d);
1034 
1035 	kirq->masked &= ~BIT(d->hwirq + KSZ_PTP_INT_START);
1036 }
1037 
1038 static void ksz_ptp_irq_unmask(struct irq_data *d)
1039 {
1040 	struct ksz_irq *kirq = irq_data_get_irq_chip_data(d);
1041 
1042 	kirq->masked |= BIT(d->hwirq + KSZ_PTP_INT_START);
1043 }
1044 
1045 static void ksz_ptp_irq_bus_lock(struct irq_data *d)
1046 {
1047 	struct ksz_irq *kirq  = irq_data_get_irq_chip_data(d);
1048 
1049 	mutex_lock(&kirq->dev->lock_irq);
1050 }
1051 
1052 static void ksz_ptp_irq_bus_sync_unlock(struct irq_data *d)
1053 {
1054 	struct ksz_irq *kirq  = irq_data_get_irq_chip_data(d);
1055 	struct ksz_device *dev = kirq->dev;
1056 	int ret;
1057 
1058 	ret = ksz_write16(dev, kirq->reg_mask, kirq->masked);
1059 	if (ret)
1060 		dev_err(dev->dev, "failed to change IRQ mask\n");
1061 
1062 	mutex_unlock(&dev->lock_irq);
1063 }
1064 
1065 static const struct irq_chip ksz_ptp_irq_chip = {
1066 	.name			= "ksz-irq",
1067 	.irq_mask		= ksz_ptp_irq_mask,
1068 	.irq_unmask		= ksz_ptp_irq_unmask,
1069 	.irq_bus_lock		= ksz_ptp_irq_bus_lock,
1070 	.irq_bus_sync_unlock	= ksz_ptp_irq_bus_sync_unlock,
1071 };
1072 
1073 static int ksz_ptp_irq_domain_map(struct irq_domain *d,
1074 				  unsigned int irq, irq_hw_number_t hwirq)
1075 {
1076 	irq_set_chip_data(irq, d->host_data);
1077 	irq_set_chip_and_handler(irq, &ksz_ptp_irq_chip, handle_level_irq);
1078 	irq_set_noprobe(irq);
1079 
1080 	return 0;
1081 }
1082 
1083 static const struct irq_domain_ops ksz_ptp_irq_domain_ops = {
1084 	.map	= ksz_ptp_irq_domain_map,
1085 	.xlate	= irq_domain_xlate_twocell,
1086 };
1087 
1088 static void ksz_ptp_msg_irq_free(struct ksz_port *port, u8 n)
1089 {
1090 	struct ksz_ptp_irq *ptpmsg_irq;
1091 
1092 	ptpmsg_irq = &port->ptpmsg_irq[n];
1093 
1094 	free_irq(ptpmsg_irq->num, ptpmsg_irq);
1095 	irq_dispose_mapping(ptpmsg_irq->num);
1096 }
1097 
1098 static int ksz_ptp_msg_irq_setup(struct ksz_port *port, u8 n)
1099 {
1100 	u16 ts_reg[] = {REG_PTP_PORT_PDRESP_TS, REG_PTP_PORT_XDELAY_TS,
1101 			REG_PTP_PORT_SYNC_TS};
1102 	static const char * const name[] = {"pdresp-msg", "xdreq-msg",
1103 					    "sync-msg"};
1104 	const struct ksz_dev_ops *ops = port->ksz_dev->dev_ops;
1105 	struct ksz_ptp_irq *ptpmsg_irq;
1106 
1107 	ptpmsg_irq = &port->ptpmsg_irq[n];
1108 
1109 	ptpmsg_irq->port = port;
1110 	ptpmsg_irq->ts_reg = ops->get_port_addr(port->num, ts_reg[n]);
1111 
1112 	snprintf(ptpmsg_irq->name, sizeof(ptpmsg_irq->name), name[n]);
1113 
1114 	ptpmsg_irq->num = irq_find_mapping(port->ptpirq.domain, n);
1115 	if (ptpmsg_irq->num < 0)
1116 		return ptpmsg_irq->num;
1117 
1118 	return request_threaded_irq(ptpmsg_irq->num, NULL,
1119 				    ksz_ptp_msg_thread_fn, IRQF_ONESHOT,
1120 				    ptpmsg_irq->name, ptpmsg_irq);
1121 }
1122 
1123 int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p)
1124 {
1125 	struct ksz_device *dev = ds->priv;
1126 	const struct ksz_dev_ops *ops = dev->dev_ops;
1127 	struct ksz_port *port = &dev->ports[p];
1128 	struct ksz_irq *ptpirq = &port->ptpirq;
1129 	int irq;
1130 	int ret;
1131 
1132 	ptpirq->dev = dev;
1133 	ptpirq->masked = 0;
1134 	ptpirq->nirqs = 3;
1135 	ptpirq->reg_mask = ops->get_port_addr(p, REG_PTP_PORT_TX_INT_ENABLE__2);
1136 	ptpirq->reg_status = ops->get_port_addr(p,
1137 						REG_PTP_PORT_TX_INT_STATUS__2);
1138 	snprintf(ptpirq->name, sizeof(ptpirq->name), "ptp-irq-%d", p);
1139 
1140 	init_completion(&port->tstamp_msg_comp);
1141 
1142 	ptpirq->domain = irq_domain_add_linear(dev->dev->of_node, ptpirq->nirqs,
1143 					       &ksz_ptp_irq_domain_ops, ptpirq);
1144 	if (!ptpirq->domain)
1145 		return -ENOMEM;
1146 
1147 	for (irq = 0; irq < ptpirq->nirqs; irq++)
1148 		irq_create_mapping(ptpirq->domain, irq);
1149 
1150 	ptpirq->irq_num = irq_find_mapping(port->pirq.domain, PORT_SRC_PTP_INT);
1151 	if (ptpirq->irq_num < 0) {
1152 		ret = ptpirq->irq_num;
1153 		goto out;
1154 	}
1155 
1156 	ret = request_threaded_irq(ptpirq->irq_num, NULL, ksz_ptp_irq_thread_fn,
1157 				   IRQF_ONESHOT, ptpirq->name, ptpirq);
1158 	if (ret)
1159 		goto out;
1160 
1161 	for (irq = 0; irq < ptpirq->nirqs; irq++) {
1162 		ret = ksz_ptp_msg_irq_setup(port, irq);
1163 		if (ret)
1164 			goto out_ptp_msg;
1165 	}
1166 
1167 	return 0;
1168 
1169 out_ptp_msg:
1170 	free_irq(ptpirq->irq_num, ptpirq);
1171 	while (irq--)
1172 		free_irq(port->ptpmsg_irq[irq].num, &port->ptpmsg_irq[irq]);
1173 out:
1174 	for (irq = 0; irq < ptpirq->nirqs; irq++)
1175 		irq_dispose_mapping(port->ptpmsg_irq[irq].num);
1176 
1177 	irq_domain_remove(ptpirq->domain);
1178 
1179 	return ret;
1180 }
1181 
1182 void ksz_ptp_irq_free(struct dsa_switch *ds, u8 p)
1183 {
1184 	struct ksz_device *dev = ds->priv;
1185 	struct ksz_port *port = &dev->ports[p];
1186 	struct ksz_irq *ptpirq = &port->ptpirq;
1187 	u8 n;
1188 
1189 	for (n = 0; n < ptpirq->nirqs; n++)
1190 		ksz_ptp_msg_irq_free(port, n);
1191 
1192 	free_irq(ptpirq->irq_num, ptpirq);
1193 	irq_dispose_mapping(ptpirq->irq_num);
1194 
1195 	irq_domain_remove(ptpirq->domain);
1196 }
1197 
1198 MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
1199 MODULE_AUTHOR("Arun Ramadoss <arun.ramadoss@microchip.com>");
1200 MODULE_DESCRIPTION("PTP support for KSZ switch");
1201 MODULE_LICENSE("GPL");
1202