1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * TI Common Platform Time Sync
  4 *
  5 * Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
  6 *
  7 */
  8#include <linux/clk-provider.h>
  9#include <linux/err.h>
 10#include <linux/if.h>
 11#include <linux/hrtimer.h>
 12#include <linux/module.h>
 13#include <linux/net_tstamp.h>
 14#include <linux/ptp_classify.h>
 15#include <linux/time.h>
 16#include <linux/uaccess.h>
 17#include <linux/workqueue.h>
 18#include <linux/if_ether.h>
 19#include <linux/if_vlan.h>
 20
 21#include "cpts.h"
 22
 23#define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */
 24#define CPTS_SKB_RX_TX_TMO 100 /*ms */
 25#define CPTS_EVENT_RX_TX_TIMEOUT (100) /* ms */
 26
 27struct cpts_skb_cb_data {
 28	u32 skb_mtype_seqid;
 29	unsigned long tmo;
 30};
 31
 32#define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
 33#define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 34
 35static int cpts_event_port(struct cpts_event *event)
 36{
 37	return (event->high >> PORT_NUMBER_SHIFT) & PORT_NUMBER_MASK;
 38}
 39
 40static int event_expired(struct cpts_event *event)
 41{
 42	return time_after(jiffies, event->tmo);
 43}
 44
 45static int event_type(struct cpts_event *event)
 46{
 47	return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
 48}
 49
 50static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
 51{
 52	u32 r = cpts_read32(cpts, intstat_raw);
 53
 54	if (r & TS_PEND_RAW) {
 55		*high = cpts_read32(cpts, event_high);
 56		*low  = cpts_read32(cpts, event_low);
 57		cpts_write32(cpts, EVENT_POP, event_pop);
 58		return 0;
 59	}
 60	return -1;
 61}
 62
 63static int cpts_purge_events(struct cpts *cpts)
 64{
 65	struct list_head *this, *next;
 66	struct cpts_event *event;
 67	int removed = 0;
 68
 69	list_for_each_safe(this, next, &cpts->events) {
 70		event = list_entry(this, struct cpts_event, list);
 71		if (event_expired(event)) {
 72			list_del_init(&event->list);
 73			list_add(&event->list, &cpts->pool);
 74			++removed;
 75		}
 76	}
 77
 78	if (removed)
 79		dev_dbg(cpts->dev, "cpts: event pool cleaned up %d\n", removed);
 80	return removed ? 0 : -1;
 81}
 82
 83static void cpts_purge_txq(struct cpts *cpts)
 84{
 85	struct cpts_skb_cb_data *skb_cb;
 86	struct sk_buff *skb, *tmp;
 87	int removed = 0;
 88
 89	skb_queue_walk_safe(&cpts->txq, skb, tmp) {
 90		skb_cb = (struct cpts_skb_cb_data *)skb->cb;
 91		if (time_after(jiffies, skb_cb->tmo)) {
 92			__skb_unlink(skb, &cpts->txq);
 93			dev_consume_skb_any(skb);
 94			++removed;
 95		}
 96	}
 97
 98	if (removed)
 99		dev_dbg(cpts->dev, "txq cleaned up %d\n", removed);
100}
101
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
102/*
103 * Returns zero if matching event type was found.
104 */
105static int cpts_fifo_read(struct cpts *cpts, int match)
106{
107	struct ptp_clock_event pevent;
108	bool need_schedule = false;
109	struct cpts_event *event;
110	unsigned long flags;
111	int i, type = -1;
112	u32 hi, lo;
113
114	spin_lock_irqsave(&cpts->lock, flags);
115
116	for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
117		if (cpts_fifo_pop(cpts, &hi, &lo))
118			break;
119
120		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
121			dev_warn(cpts->dev, "cpts: event pool empty\n");
122			break;
123		}
124
125		event = list_first_entry(&cpts->pool, struct cpts_event, list);
 
126		event->high = hi;
127		event->low = lo;
128		event->timestamp = timecounter_cyc2time(&cpts->tc, event->low);
129		type = event_type(event);
130
131		dev_dbg(cpts->dev, "CPTS_EV: %d high:%08X low:%08x\n",
132			type, event->high, event->low);
133		switch (type) {
134		case CPTS_EV_PUSH:
135			WRITE_ONCE(cpts->cur_timestamp, lo);
136			timecounter_read(&cpts->tc);
137			if (cpts->mult_new) {
138				cpts->cc.mult = cpts->mult_new;
139				cpts->mult_new = 0;
140			}
141			if (!cpts->irq_poll)
142				complete(&cpts->ts_push_complete);
143			break;
144		case CPTS_EV_TX:
 
 
 
 
 
 
 
 
145		case CPTS_EV_RX:
146			event->tmo = jiffies +
147				msecs_to_jiffies(CPTS_EVENT_RX_TX_TIMEOUT);
148
149			list_del_init(&event->list);
150			list_add_tail(&event->list, &cpts->events);
151			need_schedule = true;
152			break;
153		case CPTS_EV_ROLL:
154		case CPTS_EV_HALF:
155			break;
156		case CPTS_EV_HW:
157			pevent.timestamp = event->timestamp;
158			pevent.type = PTP_CLOCK_EXTTS;
159			pevent.index = cpts_event_port(event) - 1;
160			ptp_clock_event(cpts->clock, &pevent);
161			break;
162		default:
163			dev_err(cpts->dev, "cpts: unknown event type\n");
164			break;
165		}
166		if (type == match)
167			break;
168	}
169
170	spin_unlock_irqrestore(&cpts->lock, flags);
171
172	if (!cpts->irq_poll && need_schedule)
173		ptp_schedule_worker(cpts->clock, 0);
174
175	return type == match ? 0 : -1;
176}
177
178void cpts_misc_interrupt(struct cpts *cpts)
179{
180	cpts_fifo_read(cpts, -1);
181}
182EXPORT_SYMBOL_GPL(cpts_misc_interrupt);
183
184static u64 cpts_systim_read(const struct cyclecounter *cc)
185{
 
 
 
186	struct cpts *cpts = container_of(cc, struct cpts, cc);
187
188	return READ_ONCE(cpts->cur_timestamp);
189}
190
191static void cpts_update_cur_time(struct cpts *cpts, int match,
192				 struct ptp_system_timestamp *sts)
193{
194	unsigned long flags;
195
196	reinit_completion(&cpts->ts_push_complete);
197
198	/* use spin_lock_irqsave() here as it has to run very fast */
199	spin_lock_irqsave(&cpts->lock, flags);
200	ptp_read_system_prets(sts);
201	cpts_write32(cpts, TS_PUSH, ts_push);
202	cpts_read32(cpts, ts_push);
203	ptp_read_system_postts(sts);
204	spin_unlock_irqrestore(&cpts->lock, flags);
205
206	if (cpts->irq_poll && cpts_fifo_read(cpts, match) && match != -1)
207		dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
 
 
 
 
 
 
 
208
209	if (!cpts->irq_poll &&
210	    !wait_for_completion_timeout(&cpts->ts_push_complete, HZ))
211		dev_err(cpts->dev, "cpts: obtain a time stamp timeout\n");
212}
213
214/* PTP clock operations */
215
216static int cpts_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
217{
 
 
 
 
218	struct cpts *cpts = container_of(ptp, struct cpts, info);
219
220	mutex_lock(&cpts->ptp_clk_mutex);
 
 
 
 
 
 
 
 
 
 
 
221
222	cpts->mult_new = adjust_by_scaled_ppm(cpts->cc_mult, scaled_ppm);
223
224	cpts_update_cur_time(cpts, CPTS_EV_PUSH, NULL);
225
226	mutex_unlock(&cpts->ptp_clk_mutex);
227	return 0;
228}
229
230static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
231{
 
232	struct cpts *cpts = container_of(ptp, struct cpts, info);
233
234	mutex_lock(&cpts->ptp_clk_mutex);
235	timecounter_adjtime(&cpts->tc, delta);
236	mutex_unlock(&cpts->ptp_clk_mutex);
237
238	return 0;
239}
240
241static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
242			      struct timespec64 *ts,
243			      struct ptp_system_timestamp *sts)
244{
245	struct cpts *cpts = container_of(ptp, struct cpts, info);
246	u64 ns;
 
 
247
248	mutex_lock(&cpts->ptp_clk_mutex);
249
250	cpts_update_cur_time(cpts, CPTS_EV_PUSH, sts);
251
252	ns = timecounter_read(&cpts->tc);
253	mutex_unlock(&cpts->ptp_clk_mutex);
254
255	*ts = ns_to_timespec64(ns);
256
257	return 0;
258}
259
260static int cpts_ptp_settime(struct ptp_clock_info *ptp,
261			    const struct timespec64 *ts)
262{
263	struct cpts *cpts = container_of(ptp, struct cpts, info);
264	u64 ns;
 
 
265
266	ns = timespec64_to_ns(ts);
267
268	mutex_lock(&cpts->ptp_clk_mutex);
269	timecounter_init(&cpts->tc, &cpts->cc, ns);
270	mutex_unlock(&cpts->ptp_clk_mutex);
271
272	return 0;
273}
274
275static int cpts_extts_enable(struct cpts *cpts, u32 index, int on)
276{
277	u32 v;
278
279	if (((cpts->hw_ts_enable & BIT(index)) >> index) == on)
280		return 0;
281
282	mutex_lock(&cpts->ptp_clk_mutex);
283
284	v = cpts_read32(cpts, control);
285	if (on) {
286		v |= BIT(8 + index);
287		cpts->hw_ts_enable |= BIT(index);
288	} else {
289		v &= ~BIT(8 + index);
290		cpts->hw_ts_enable &= ~BIT(index);
291	}
292	cpts_write32(cpts, v, control);
293
294	mutex_unlock(&cpts->ptp_clk_mutex);
295
296	return 0;
297}
298
299static int cpts_ptp_enable(struct ptp_clock_info *ptp,
300			   struct ptp_clock_request *rq, int on)
301{
302	struct cpts *cpts = container_of(ptp, struct cpts, info);
303
304	switch (rq->type) {
305	case PTP_CLK_REQ_EXTTS:
306		return cpts_extts_enable(cpts, rq->extts.index, on);
307	default:
308		break;
309	}
310
311	return -EOPNOTSUPP;
312}
313
314static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
315{
316	struct sk_buff_head txq_list;
317	struct sk_buff *skb, *tmp;
318	unsigned long flags;
319	bool found = false;
320	u32 mtype_seqid;
321
322	mtype_seqid = event->high &
323		      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
324		       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
325		       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
326
327	__skb_queue_head_init(&txq_list);
328
329	spin_lock_irqsave(&cpts->txq.lock, flags);
330	skb_queue_splice_init(&cpts->txq, &txq_list);
331	spin_unlock_irqrestore(&cpts->txq.lock, flags);
332
333	skb_queue_walk_safe(&txq_list, skb, tmp) {
334		struct skb_shared_hwtstamps ssh;
335		struct cpts_skb_cb_data *skb_cb =
336					(struct cpts_skb_cb_data *)skb->cb;
337
338		if (mtype_seqid == skb_cb->skb_mtype_seqid) {
339			memset(&ssh, 0, sizeof(ssh));
340			ssh.hwtstamp = ns_to_ktime(event->timestamp);
341			skb_tstamp_tx(skb, &ssh);
342			found = true;
343			__skb_unlink(skb, &txq_list);
344			dev_consume_skb_any(skb);
345			dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
346				mtype_seqid);
347			break;
348		}
349
350		if (time_after(jiffies, skb_cb->tmo)) {
351			/* timeout any expired skbs over 1s */
352			dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
353			__skb_unlink(skb, &txq_list);
354			dev_consume_skb_any(skb);
355		}
356	}
357
358	spin_lock_irqsave(&cpts->txq.lock, flags);
359	skb_queue_splice(&txq_list, &cpts->txq);
360	spin_unlock_irqrestore(&cpts->txq.lock, flags);
361
362	return found;
363}
364
365static void cpts_process_events(struct cpts *cpts)
366{
367	struct list_head *this, *next;
368	struct cpts_event *event;
369	LIST_HEAD(events_free);
370	unsigned long flags;
371	LIST_HEAD(events);
372
373	spin_lock_irqsave(&cpts->lock, flags);
374	list_splice_init(&cpts->events, &events);
375	spin_unlock_irqrestore(&cpts->lock, flags);
376
377	list_for_each_safe(this, next, &events) {
378		event = list_entry(this, struct cpts_event, list);
379		if (cpts_match_tx_ts(cpts, event) ||
380		    time_after(jiffies, event->tmo)) {
381			list_del_init(&event->list);
382			list_add(&event->list, &events_free);
383		}
384	}
385
386	spin_lock_irqsave(&cpts->lock, flags);
387	list_splice_tail(&events, &cpts->events);
388	list_splice_tail(&events_free, &cpts->pool);
389	spin_unlock_irqrestore(&cpts->lock, flags);
390}
391
392static long cpts_overflow_check(struct ptp_clock_info *ptp)
393{
394	struct cpts *cpts = container_of(ptp, struct cpts, info);
395	unsigned long delay = cpts->ov_check_period;
 
396	unsigned long flags;
397	u64 ns;
398
399	mutex_lock(&cpts->ptp_clk_mutex);
400
401	cpts_update_cur_time(cpts, -1, NULL);
402	ns = timecounter_read(&cpts->tc);
403
404	cpts_process_events(cpts);
405
406	spin_lock_irqsave(&cpts->txq.lock, flags);
407	if (!skb_queue_empty(&cpts->txq)) {
408		cpts_purge_txq(cpts);
409		if (!skb_queue_empty(&cpts->txq))
410			delay = CPTS_SKB_TX_WORK_TIMEOUT;
411	}
412	spin_unlock_irqrestore(&cpts->txq.lock, flags);
413
414	dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
415	mutex_unlock(&cpts->ptp_clk_mutex);
416	return (long)delay;
417}
418
419static const struct ptp_clock_info cpts_info = {
420	.owner		= THIS_MODULE,
421	.name		= "CTPS timer",
422	.max_adj	= 1000000,
423	.n_ext_ts	= 0,
424	.n_pins		= 0,
425	.pps		= 0,
426	.adjfine	= cpts_ptp_adjfine,
427	.adjtime	= cpts_ptp_adjtime,
428	.gettimex64	= cpts_ptp_gettimeex,
429	.settime64	= cpts_ptp_settime,
430	.enable		= cpts_ptp_enable,
431	.do_aux_work	= cpts_overflow_check,
432};
433
434static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
 
435{
436	unsigned int ptp_class = ptp_classify_raw(skb);
437	struct ptp_header *hdr;
438	u8 msgtype;
439	u16 seqid;
440
441	if (ptp_class == PTP_CLASS_NONE)
 
 
 
 
 
 
 
 
 
 
 
 
442		return 0;
 
443
444	hdr = ptp_parse_header(skb, ptp_class);
445	if (!hdr)
446		return 0;
447
448	msgtype = ptp_get_msgtype(hdr, ptp_class);
449	seqid	= ntohs(hdr->sequence_id);
 
 
450
451	*mtype_seqid  = (msgtype & MESSAGE_TYPE_MASK) << MESSAGE_TYPE_SHIFT;
452	*mtype_seqid |= (seqid & SEQUENCE_ID_MASK) << SEQUENCE_ID_SHIFT;
453
454	return 1;
455}
456
457static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
458			int ev_type, u32 skb_mtype_seqid)
459{
460	struct list_head *this, *next;
461	struct cpts_event *event;
 
 
462	unsigned long flags;
463	u32 mtype_seqid;
464	u64 ns = 0;
 
 
 
465
466	cpts_fifo_read(cpts, -1);
467	spin_lock_irqsave(&cpts->lock, flags);
 
468	list_for_each_safe(this, next, &cpts->events) {
469		event = list_entry(this, struct cpts_event, list);
470		if (event_expired(event)) {
471			list_del_init(&event->list);
472			list_add(&event->list, &cpts->pool);
473			continue;
474		}
475
476		mtype_seqid = event->high &
477			      ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
478			       (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
479			       (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
480
481		if (mtype_seqid == skb_mtype_seqid) {
482			ns = event->timestamp;
483			list_del_init(&event->list);
484			list_add(&event->list, &cpts->pool);
485			break;
486		}
487	}
 
 
 
 
 
 
 
 
 
 
 
 
 
488	spin_unlock_irqrestore(&cpts->lock, flags);
489
490	return ns;
491}
492
493void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
494{
495	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
496	struct skb_shared_hwtstamps *ssh;
497	int ret;
498	u64 ns;
 
499
500	/* cpts_rx_timestamp() is called before eth_type_trans(), so
501	 * skb MAC Hdr properties are not configured yet. Hence need to
502	 * reset skb MAC header here
503	 */
504	skb_reset_mac_header(skb);
505	ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
506	if (!ret)
507		return;
508
509	skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
510
511	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
512		__func__, skb_cb->skb_mtype_seqid);
513
514	ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
515	if (!ns)
516		return;
517	ssh = skb_hwtstamps(skb);
518	memset(ssh, 0, sizeof(*ssh));
519	ssh->hwtstamp = ns_to_ktime(ns);
520}
521EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
522
523void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
524{
525	struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
526	int ret;
527
528	if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
529		return;
530
531	ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
532	if (!ret)
533		return;
534
535	skb_cb->skb_mtype_seqid |= (CPTS_EV_TX << EVENT_TYPE_SHIFT);
536
537	dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
538		__func__, skb_cb->skb_mtype_seqid);
539
540	/* Always defer TX TS processing to PTP worker */
541	skb_get(skb);
542	/* get the timestamp for timeouts */
543	skb_cb->tmo = jiffies + msecs_to_jiffies(CPTS_SKB_RX_TX_TMO);
544	skb_queue_tail(&cpts->txq, skb);
545	ptp_schedule_worker(cpts->clock, 0);
546}
547EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
548
549int cpts_register(struct cpts *cpts)
550{
551	int err, i;
552
553	skb_queue_head_init(&cpts->txq);
554	INIT_LIST_HEAD(&cpts->events);
555	INIT_LIST_HEAD(&cpts->pool);
556	for (i = 0; i < CPTS_MAX_EVENTS; i++)
557		list_add(&cpts->pool_data[i].list, &cpts->pool);
558
559	err = clk_enable(cpts->refclk);
560	if (err)
561		return err;
562
563	cpts_write32(cpts, CPTS_EN, control);
564	cpts_write32(cpts, TS_PEND_EN, int_enable);
565
566	timecounter_init(&cpts->tc, &cpts->cc, ktime_get_real_ns());
567
568	cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
569	if (IS_ERR(cpts->clock)) {
570		err = PTR_ERR(cpts->clock);
571		cpts->clock = NULL;
572		goto err_ptp;
573	}
574	cpts->phc_index = ptp_clock_index(cpts->clock);
575
576	ptp_schedule_worker(cpts->clock, cpts->ov_check_period);
577	return 0;
578
579err_ptp:
580	clk_disable(cpts->refclk);
581	return err;
582}
583EXPORT_SYMBOL_GPL(cpts_register);
584
585void cpts_unregister(struct cpts *cpts)
586{
587	if (WARN_ON(!cpts->clock))
588		return;
589
590	ptp_clock_unregister(cpts->clock);
591	cpts->clock = NULL;
592	cpts->phc_index = -1;
593
594	cpts_write32(cpts, 0, int_enable);
595	cpts_write32(cpts, 0, control);
596
597	/* Drop all packet */
598	skb_queue_purge(&cpts->txq);
599
600	clk_disable(cpts->refclk);
601}
602EXPORT_SYMBOL_GPL(cpts_unregister);
603
604static void cpts_calc_mult_shift(struct cpts *cpts)
605{
606	u64 frac, maxsec, ns;
607	u32 freq;
608
609	freq = clk_get_rate(cpts->refclk);
610
611	/* Calc the maximum number of seconds which we can run before
612	 * wrapping around.
613	 */
614	maxsec = cpts->cc.mask;
615	do_div(maxsec, freq);
616	/* limit conversation rate to 10 sec as higher values will produce
617	 * too small mult factors and so reduce the conversion accuracy
618	 */
619	if (maxsec > 10)
620		maxsec = 10;
621
622	/* Calc overflow check period (maxsec / 2) */
623	cpts->ov_check_period = (HZ * maxsec) / 2;
624	dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
625		 cpts->ov_check_period);
626
627	if (cpts->cc.mult || cpts->cc.shift)
628		return;
629
630	clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
631			       freq, NSEC_PER_SEC, maxsec);
632
633	frac = 0;
634	ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
635
636	dev_info(cpts->dev,
637		 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
638		 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
639}
640
641static void cpts_clk_unregister(void *clk)
642{
643	clk_hw_unregister_mux(clk);
644}
645
646static void cpts_clk_del_provider(void *np)
647{
648	of_clk_del_provider(np);
649}
650
651static int cpts_of_mux_clk_setup(struct cpts *cpts, struct device_node *node)
652{
653	struct device_node *refclk_np;
654	const char **parent_names;
655	unsigned int num_parents;
656	struct clk_hw *clk_hw;
657	int ret = -EINVAL;
658	u32 *mux_table;
659
660	refclk_np = of_get_child_by_name(node, "cpts-refclk-mux");
661	if (!refclk_np)
662		/* refclk selection supported not for all SoCs */
663		return 0;
664
665	num_parents = of_clk_get_parent_count(refclk_np);
666	if (num_parents < 1) {
667		dev_err(cpts->dev, "mux-clock %s must have parents\n",
668			refclk_np->name);
669		goto mux_fail;
670	}
671
672	parent_names = devm_kcalloc(cpts->dev, num_parents,
673				    sizeof(*parent_names), GFP_KERNEL);
674
675	mux_table = devm_kcalloc(cpts->dev, num_parents, sizeof(*mux_table),
676				 GFP_KERNEL);
677	if (!mux_table || !parent_names) {
678		ret = -ENOMEM;
679		goto mux_fail;
680	}
681
682	of_clk_parent_fill(refclk_np, parent_names, num_parents);
683
684	ret = of_property_read_variable_u32_array(refclk_np, "ti,mux-tbl",
685						  mux_table,
686						  num_parents, num_parents);
687	if (ret < 0)
688		goto mux_fail;
689
690	clk_hw = clk_hw_register_mux_table(cpts->dev, refclk_np->name,
691					   parent_names, num_parents,
692					   0,
693					   &cpts->reg->rftclk_sel, 0, 0x1F,
694					   0, mux_table, NULL);
695	if (IS_ERR(clk_hw)) {
696		ret = PTR_ERR(clk_hw);
697		goto mux_fail;
698	}
699
700	ret = devm_add_action_or_reset(cpts->dev, cpts_clk_unregister, clk_hw);
 
 
701	if (ret) {
702		dev_err(cpts->dev, "add clkmux unreg action %d", ret);
703		goto mux_fail;
704	}
705
706	ret = of_clk_add_hw_provider(refclk_np, of_clk_hw_simple_get, clk_hw);
707	if (ret)
708		goto mux_fail;
709
710	ret = devm_add_action_or_reset(cpts->dev, cpts_clk_del_provider,
 
711				       refclk_np);
712	if (ret) {
713		dev_err(cpts->dev, "add clkmux provider unreg action %d", ret);
714		goto mux_fail;
715	}
716
717	return ret;
718
719mux_fail:
720	of_node_put(refclk_np);
721	return ret;
722}
723
724static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
725{
726	int ret = -EINVAL;
727	u32 prop;
728
729	if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
730		cpts->cc.mult = prop;
731
732	if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
733		cpts->cc.shift = prop;
734
735	if ((cpts->cc.mult && !cpts->cc.shift) ||
736	    (!cpts->cc.mult && cpts->cc.shift))
737		goto of_error;
738
739	return cpts_of_mux_clk_setup(cpts, node);
740
741of_error:
742	dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
743	return ret;
744}
745
746struct cpts *cpts_create(struct device *dev, void __iomem *regs,
747			 struct device_node *node, u32 n_ext_ts)
748{
749	struct cpts *cpts;
750	int ret;
751
752	cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
753	if (!cpts)
754		return ERR_PTR(-ENOMEM);
755
756	cpts->dev = dev;
757	cpts->reg = (struct cpsw_cpts __iomem *)regs;
758	cpts->irq_poll = true;
759	spin_lock_init(&cpts->lock);
760	mutex_init(&cpts->ptp_clk_mutex);
761	init_completion(&cpts->ts_push_complete);
762
763	ret = cpts_of_parse(cpts, node);
764	if (ret)
765		return ERR_PTR(ret);
766
767	cpts->refclk = devm_get_clk_from_child(dev, node, "cpts");
768	if (IS_ERR(cpts->refclk))
769		/* try get clk from dev node for compatibility */
770		cpts->refclk = devm_clk_get(dev, "cpts");
771
772	if (IS_ERR(cpts->refclk)) {
773		dev_err(dev, "Failed to get cpts refclk %ld\n",
774			PTR_ERR(cpts->refclk));
775		return ERR_CAST(cpts->refclk);
776	}
777
778	ret = clk_prepare(cpts->refclk);
779	if (ret)
780		return ERR_PTR(ret);
781
782	cpts->cc.read = cpts_systim_read;
783	cpts->cc.mask = CLOCKSOURCE_MASK(32);
784	cpts->info = cpts_info;
785	cpts->phc_index = -1;
786
787	if (n_ext_ts)
788		cpts->info.n_ext_ts = n_ext_ts;
789
790	cpts_calc_mult_shift(cpts);
791	/* save cc.mult original value as it can be modified
792	 * by cpts_ptp_adjfine().
793	 */
794	cpts->cc_mult = cpts->cc.mult;
795
796	return cpts;
797}
798EXPORT_SYMBOL_GPL(cpts_create);
799
800void cpts_release(struct cpts *cpts)
801{
802	if (!cpts)
803		return;
804
805	if (WARN_ON(!cpts->refclk))
806		return;
807
808	clk_unprepare(cpts->refclk);
809}
810EXPORT_SYMBOL_GPL(cpts_release);
811
812MODULE_LICENSE("GPL v2");
813MODULE_DESCRIPTION("TI CPTS driver");
814MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");