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
27 struct 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
cpts_event_port(struct cpts_event * event)35 static int cpts_event_port(struct cpts_event *event)
36 {
37 return (event->high >> PORT_NUMBER_SHIFT) & PORT_NUMBER_MASK;
38 }
39
event_expired(struct cpts_event * event)40 static int event_expired(struct cpts_event *event)
41 {
42 return time_after(jiffies, event->tmo);
43 }
44
event_type(struct cpts_event * event)45 static int event_type(struct cpts_event *event)
46 {
47 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
48 }
49
cpts_fifo_pop(struct cpts * cpts,u32 * high,u32 * low)50 static 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
cpts_purge_events(struct cpts * cpts)63 static 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
cpts_purge_txq(struct cpts * cpts)83 static 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 */
cpts_fifo_read(struct cpts * cpts,int match)105 static 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
cpts_misc_interrupt(struct cpts * cpts)178 void cpts_misc_interrupt(struct cpts *cpts)
179 {
180 cpts_fifo_read(cpts, -1);
181 }
182 EXPORT_SYMBOL_GPL(cpts_misc_interrupt);
183
cpts_systim_read(const struct cyclecounter * cc)184 static 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
cpts_update_cur_time(struct cpts * cpts,int match,struct ptp_system_timestamp * sts)191 static 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
cpts_ptp_adjfreq(struct ptp_clock_info * ptp,s32 ppb)216 static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
217 {
218 struct cpts *cpts = container_of(ptp, struct cpts, info);
219 int neg_adj = 0;
220 u32 diff, mult;
221 u64 adj;
222
223 if (ppb < 0) {
224 neg_adj = 1;
225 ppb = -ppb;
226 }
227 mult = cpts->cc_mult;
228 adj = mult;
229 adj *= ppb;
230 diff = div_u64(adj, 1000000000ULL);
231
232 mutex_lock(&cpts->ptp_clk_mutex);
233
234 cpts->mult_new = neg_adj ? mult - diff : mult + diff;
235
236 cpts_update_cur_time(cpts, CPTS_EV_PUSH, NULL);
237
238 mutex_unlock(&cpts->ptp_clk_mutex);
239 return 0;
240 }
241
cpts_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)242 static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
243 {
244 struct cpts *cpts = container_of(ptp, struct cpts, info);
245
246 mutex_lock(&cpts->ptp_clk_mutex);
247 timecounter_adjtime(&cpts->tc, delta);
248 mutex_unlock(&cpts->ptp_clk_mutex);
249
250 return 0;
251 }
252
cpts_ptp_gettimeex(struct ptp_clock_info * ptp,struct timespec64 * ts,struct ptp_system_timestamp * sts)253 static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
254 struct timespec64 *ts,
255 struct ptp_system_timestamp *sts)
256 {
257 struct cpts *cpts = container_of(ptp, struct cpts, info);
258 u64 ns;
259
260 mutex_lock(&cpts->ptp_clk_mutex);
261
262 cpts_update_cur_time(cpts, CPTS_EV_PUSH, sts);
263
264 ns = timecounter_read(&cpts->tc);
265 mutex_unlock(&cpts->ptp_clk_mutex);
266
267 *ts = ns_to_timespec64(ns);
268
269 return 0;
270 }
271
cpts_ptp_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)272 static int cpts_ptp_settime(struct ptp_clock_info *ptp,
273 const struct timespec64 *ts)
274 {
275 struct cpts *cpts = container_of(ptp, struct cpts, info);
276 u64 ns;
277
278 ns = timespec64_to_ns(ts);
279
280 mutex_lock(&cpts->ptp_clk_mutex);
281 timecounter_init(&cpts->tc, &cpts->cc, ns);
282 mutex_unlock(&cpts->ptp_clk_mutex);
283
284 return 0;
285 }
286
cpts_extts_enable(struct cpts * cpts,u32 index,int on)287 static int cpts_extts_enable(struct cpts *cpts, u32 index, int on)
288 {
289 u32 v;
290
291 if (((cpts->hw_ts_enable & BIT(index)) >> index) == on)
292 return 0;
293
294 mutex_lock(&cpts->ptp_clk_mutex);
295
296 v = cpts_read32(cpts, control);
297 if (on) {
298 v |= BIT(8 + index);
299 cpts->hw_ts_enable |= BIT(index);
300 } else {
301 v &= ~BIT(8 + index);
302 cpts->hw_ts_enable &= ~BIT(index);
303 }
304 cpts_write32(cpts, v, control);
305
306 mutex_unlock(&cpts->ptp_clk_mutex);
307
308 return 0;
309 }
310
cpts_ptp_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)311 static int cpts_ptp_enable(struct ptp_clock_info *ptp,
312 struct ptp_clock_request *rq, int on)
313 {
314 struct cpts *cpts = container_of(ptp, struct cpts, info);
315
316 switch (rq->type) {
317 case PTP_CLK_REQ_EXTTS:
318 return cpts_extts_enable(cpts, rq->extts.index, on);
319 default:
320 break;
321 }
322
323 return -EOPNOTSUPP;
324 }
325
cpts_match_tx_ts(struct cpts * cpts,struct cpts_event * event)326 static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
327 {
328 struct sk_buff_head txq_list;
329 struct sk_buff *skb, *tmp;
330 unsigned long flags;
331 bool found = false;
332 u32 mtype_seqid;
333
334 mtype_seqid = event->high &
335 ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
336 (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
337 (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
338
339 __skb_queue_head_init(&txq_list);
340
341 spin_lock_irqsave(&cpts->txq.lock, flags);
342 skb_queue_splice_init(&cpts->txq, &txq_list);
343 spin_unlock_irqrestore(&cpts->txq.lock, flags);
344
345 skb_queue_walk_safe(&txq_list, skb, tmp) {
346 struct skb_shared_hwtstamps ssh;
347 struct cpts_skb_cb_data *skb_cb =
348 (struct cpts_skb_cb_data *)skb->cb;
349
350 if (mtype_seqid == skb_cb->skb_mtype_seqid) {
351 memset(&ssh, 0, sizeof(ssh));
352 ssh.hwtstamp = ns_to_ktime(event->timestamp);
353 skb_tstamp_tx(skb, &ssh);
354 found = true;
355 __skb_unlink(skb, &txq_list);
356 dev_consume_skb_any(skb);
357 dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
358 mtype_seqid);
359 break;
360 }
361
362 if (time_after(jiffies, skb_cb->tmo)) {
363 /* timeout any expired skbs over 1s */
364 dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
365 __skb_unlink(skb, &txq_list);
366 dev_consume_skb_any(skb);
367 }
368 }
369
370 spin_lock_irqsave(&cpts->txq.lock, flags);
371 skb_queue_splice(&txq_list, &cpts->txq);
372 spin_unlock_irqrestore(&cpts->txq.lock, flags);
373
374 return found;
375 }
376
cpts_process_events(struct cpts * cpts)377 static void cpts_process_events(struct cpts *cpts)
378 {
379 struct list_head *this, *next;
380 struct cpts_event *event;
381 LIST_HEAD(events_free);
382 unsigned long flags;
383 LIST_HEAD(events);
384
385 spin_lock_irqsave(&cpts->lock, flags);
386 list_splice_init(&cpts->events, &events);
387 spin_unlock_irqrestore(&cpts->lock, flags);
388
389 list_for_each_safe(this, next, &events) {
390 event = list_entry(this, struct cpts_event, list);
391 if (cpts_match_tx_ts(cpts, event) ||
392 time_after(jiffies, event->tmo)) {
393 list_del_init(&event->list);
394 list_add(&event->list, &events_free);
395 }
396 }
397
398 spin_lock_irqsave(&cpts->lock, flags);
399 list_splice_tail(&events, &cpts->events);
400 list_splice_tail(&events_free, &cpts->pool);
401 spin_unlock_irqrestore(&cpts->lock, flags);
402 }
403
cpts_overflow_check(struct ptp_clock_info * ptp)404 static long cpts_overflow_check(struct ptp_clock_info *ptp)
405 {
406 struct cpts *cpts = container_of(ptp, struct cpts, info);
407 unsigned long delay = cpts->ov_check_period;
408 unsigned long flags;
409 u64 ns;
410
411 mutex_lock(&cpts->ptp_clk_mutex);
412
413 cpts_update_cur_time(cpts, -1, NULL);
414 ns = timecounter_read(&cpts->tc);
415
416 cpts_process_events(cpts);
417
418 spin_lock_irqsave(&cpts->txq.lock, flags);
419 if (!skb_queue_empty(&cpts->txq)) {
420 cpts_purge_txq(cpts);
421 if (!skb_queue_empty(&cpts->txq))
422 delay = CPTS_SKB_TX_WORK_TIMEOUT;
423 }
424 spin_unlock_irqrestore(&cpts->txq.lock, flags);
425
426 dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
427 mutex_unlock(&cpts->ptp_clk_mutex);
428 return (long)delay;
429 }
430
431 static const struct ptp_clock_info cpts_info = {
432 .owner = THIS_MODULE,
433 .name = "CTPS timer",
434 .max_adj = 1000000,
435 .n_ext_ts = 0,
436 .n_pins = 0,
437 .pps = 0,
438 .adjfreq = cpts_ptp_adjfreq,
439 .adjtime = cpts_ptp_adjtime,
440 .gettimex64 = cpts_ptp_gettimeex,
441 .settime64 = cpts_ptp_settime,
442 .enable = cpts_ptp_enable,
443 .do_aux_work = cpts_overflow_check,
444 };
445
cpts_skb_get_mtype_seqid(struct sk_buff * skb,u32 * mtype_seqid)446 static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
447 {
448 unsigned int ptp_class = ptp_classify_raw(skb);
449 struct ptp_header *hdr;
450 u8 msgtype;
451 u16 seqid;
452
453 if (ptp_class == PTP_CLASS_NONE)
454 return 0;
455
456 hdr = ptp_parse_header(skb, ptp_class);
457 if (!hdr)
458 return 0;
459
460 msgtype = ptp_get_msgtype(hdr, ptp_class);
461 seqid = ntohs(hdr->sequence_id);
462
463 *mtype_seqid = (msgtype & MESSAGE_TYPE_MASK) << MESSAGE_TYPE_SHIFT;
464 *mtype_seqid |= (seqid & SEQUENCE_ID_MASK) << SEQUENCE_ID_SHIFT;
465
466 return 1;
467 }
468
cpts_find_ts(struct cpts * cpts,struct sk_buff * skb,int ev_type,u32 skb_mtype_seqid)469 static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
470 int ev_type, u32 skb_mtype_seqid)
471 {
472 struct list_head *this, *next;
473 struct cpts_event *event;
474 unsigned long flags;
475 u32 mtype_seqid;
476 u64 ns = 0;
477
478 cpts_fifo_read(cpts, -1);
479 spin_lock_irqsave(&cpts->lock, flags);
480 list_for_each_safe(this, next, &cpts->events) {
481 event = list_entry(this, struct cpts_event, list);
482 if (event_expired(event)) {
483 list_del_init(&event->list);
484 list_add(&event->list, &cpts->pool);
485 continue;
486 }
487
488 mtype_seqid = event->high &
489 ((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
490 (SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
491 (EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
492
493 if (mtype_seqid == skb_mtype_seqid) {
494 ns = event->timestamp;
495 list_del_init(&event->list);
496 list_add(&event->list, &cpts->pool);
497 break;
498 }
499 }
500 spin_unlock_irqrestore(&cpts->lock, flags);
501
502 return ns;
503 }
504
cpts_rx_timestamp(struct cpts * cpts,struct sk_buff * skb)505 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
506 {
507 struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
508 struct skb_shared_hwtstamps *ssh;
509 int ret;
510 u64 ns;
511
512 /* cpts_rx_timestamp() is called before eth_type_trans(), so
513 * skb MAC Hdr properties are not configured yet. Hence need to
514 * reset skb MAC header here
515 */
516 skb_reset_mac_header(skb);
517 ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
518 if (!ret)
519 return;
520
521 skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
522
523 dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
524 __func__, skb_cb->skb_mtype_seqid);
525
526 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
527 if (!ns)
528 return;
529 ssh = skb_hwtstamps(skb);
530 memset(ssh, 0, sizeof(*ssh));
531 ssh->hwtstamp = ns_to_ktime(ns);
532 }
533 EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
534
cpts_tx_timestamp(struct cpts * cpts,struct sk_buff * skb)535 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
536 {
537 struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
538 int ret;
539
540 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
541 return;
542
543 ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
544 if (!ret)
545 return;
546
547 skb_cb->skb_mtype_seqid |= (CPTS_EV_TX << EVENT_TYPE_SHIFT);
548
549 dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
550 __func__, skb_cb->skb_mtype_seqid);
551
552 /* Always defer TX TS processing to PTP worker */
553 skb_get(skb);
554 /* get the timestamp for timeouts */
555 skb_cb->tmo = jiffies + msecs_to_jiffies(CPTS_SKB_RX_TX_TMO);
556 skb_queue_tail(&cpts->txq, skb);
557 ptp_schedule_worker(cpts->clock, 0);
558 }
559 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
560
cpts_register(struct cpts * cpts)561 int cpts_register(struct cpts *cpts)
562 {
563 int err, i;
564
565 skb_queue_head_init(&cpts->txq);
566 INIT_LIST_HEAD(&cpts->events);
567 INIT_LIST_HEAD(&cpts->pool);
568 for (i = 0; i < CPTS_MAX_EVENTS; i++)
569 list_add(&cpts->pool_data[i].list, &cpts->pool);
570
571 err = clk_enable(cpts->refclk);
572 if (err)
573 return err;
574
575 cpts_write32(cpts, CPTS_EN, control);
576 cpts_write32(cpts, TS_PEND_EN, int_enable);
577
578 timecounter_init(&cpts->tc, &cpts->cc, ktime_get_real_ns());
579
580 cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
581 if (IS_ERR(cpts->clock)) {
582 err = PTR_ERR(cpts->clock);
583 cpts->clock = NULL;
584 goto err_ptp;
585 }
586 cpts->phc_index = ptp_clock_index(cpts->clock);
587
588 ptp_schedule_worker(cpts->clock, cpts->ov_check_period);
589 return 0;
590
591 err_ptp:
592 clk_disable(cpts->refclk);
593 return err;
594 }
595 EXPORT_SYMBOL_GPL(cpts_register);
596
cpts_unregister(struct cpts * cpts)597 void cpts_unregister(struct cpts *cpts)
598 {
599 if (WARN_ON(!cpts->clock))
600 return;
601
602 ptp_clock_unregister(cpts->clock);
603 cpts->clock = NULL;
604 cpts->phc_index = -1;
605
606 cpts_write32(cpts, 0, int_enable);
607 cpts_write32(cpts, 0, control);
608
609 /* Drop all packet */
610 skb_queue_purge(&cpts->txq);
611
612 clk_disable(cpts->refclk);
613 }
614 EXPORT_SYMBOL_GPL(cpts_unregister);
615
cpts_calc_mult_shift(struct cpts * cpts)616 static void cpts_calc_mult_shift(struct cpts *cpts)
617 {
618 u64 frac, maxsec, ns;
619 u32 freq;
620
621 freq = clk_get_rate(cpts->refclk);
622
623 /* Calc the maximum number of seconds which we can run before
624 * wrapping around.
625 */
626 maxsec = cpts->cc.mask;
627 do_div(maxsec, freq);
628 /* limit conversation rate to 10 sec as higher values will produce
629 * too small mult factors and so reduce the conversion accuracy
630 */
631 if (maxsec > 10)
632 maxsec = 10;
633
634 /* Calc overflow check period (maxsec / 2) */
635 cpts->ov_check_period = (HZ * maxsec) / 2;
636 dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
637 cpts->ov_check_period);
638
639 if (cpts->cc.mult || cpts->cc.shift)
640 return;
641
642 clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
643 freq, NSEC_PER_SEC, maxsec);
644
645 frac = 0;
646 ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
647
648 dev_info(cpts->dev,
649 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
650 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
651 }
652
cpts_of_mux_clk_setup(struct cpts * cpts,struct device_node * node)653 static int cpts_of_mux_clk_setup(struct cpts *cpts, struct device_node *node)
654 {
655 struct device_node *refclk_np;
656 const char **parent_names;
657 unsigned int num_parents;
658 struct clk_hw *clk_hw;
659 int ret = -EINVAL;
660 u32 *mux_table;
661
662 refclk_np = of_get_child_by_name(node, "cpts-refclk-mux");
663 if (!refclk_np)
664 /* refclk selection supported not for all SoCs */
665 return 0;
666
667 num_parents = of_clk_get_parent_count(refclk_np);
668 if (num_parents < 1) {
669 dev_err(cpts->dev, "mux-clock %s must have parents\n",
670 refclk_np->name);
671 goto mux_fail;
672 }
673
674 parent_names = devm_kzalloc(cpts->dev, (sizeof(char *) * num_parents),
675 GFP_KERNEL);
676
677 mux_table = devm_kzalloc(cpts->dev, sizeof(*mux_table) * num_parents,
678 GFP_KERNEL);
679 if (!mux_table || !parent_names) {
680 ret = -ENOMEM;
681 goto mux_fail;
682 }
683
684 of_clk_parent_fill(refclk_np, parent_names, num_parents);
685
686 ret = of_property_read_variable_u32_array(refclk_np, "ti,mux-tbl",
687 mux_table,
688 num_parents, num_parents);
689 if (ret < 0)
690 goto mux_fail;
691
692 clk_hw = clk_hw_register_mux_table(cpts->dev, refclk_np->name,
693 parent_names, num_parents,
694 0,
695 &cpts->reg->rftclk_sel, 0, 0x1F,
696 0, mux_table, NULL);
697 if (IS_ERR(clk_hw)) {
698 ret = PTR_ERR(clk_hw);
699 goto mux_fail;
700 }
701
702 ret = devm_add_action_or_reset(cpts->dev,
703 (void(*)(void *))clk_hw_unregister_mux,
704 clk_hw);
705 if (ret) {
706 dev_err(cpts->dev, "add clkmux unreg action %d", ret);
707 goto mux_fail;
708 }
709
710 ret = of_clk_add_hw_provider(refclk_np, of_clk_hw_simple_get, clk_hw);
711 if (ret)
712 goto mux_fail;
713
714 ret = devm_add_action_or_reset(cpts->dev,
715 (void(*)(void *))of_clk_del_provider,
716 refclk_np);
717 if (ret) {
718 dev_err(cpts->dev, "add clkmux provider unreg action %d", ret);
719 goto mux_fail;
720 }
721
722 return ret;
723
724 mux_fail:
725 of_node_put(refclk_np);
726 return ret;
727 }
728
cpts_of_parse(struct cpts * cpts,struct device_node * node)729 static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
730 {
731 int ret = -EINVAL;
732 u32 prop;
733
734 if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
735 cpts->cc.mult = prop;
736
737 if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
738 cpts->cc.shift = prop;
739
740 if ((cpts->cc.mult && !cpts->cc.shift) ||
741 (!cpts->cc.mult && cpts->cc.shift))
742 goto of_error;
743
744 return cpts_of_mux_clk_setup(cpts, node);
745
746 of_error:
747 dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
748 return ret;
749 }
750
cpts_create(struct device * dev,void __iomem * regs,struct device_node * node,u32 n_ext_ts)751 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
752 struct device_node *node, u32 n_ext_ts)
753 {
754 struct cpts *cpts;
755 int ret;
756
757 cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
758 if (!cpts)
759 return ERR_PTR(-ENOMEM);
760
761 cpts->dev = dev;
762 cpts->reg = (struct cpsw_cpts __iomem *)regs;
763 cpts->irq_poll = true;
764 spin_lock_init(&cpts->lock);
765 mutex_init(&cpts->ptp_clk_mutex);
766 init_completion(&cpts->ts_push_complete);
767
768 ret = cpts_of_parse(cpts, node);
769 if (ret)
770 return ERR_PTR(ret);
771
772 cpts->refclk = devm_get_clk_from_child(dev, node, "cpts");
773 if (IS_ERR(cpts->refclk))
774 /* try get clk from dev node for compatibility */
775 cpts->refclk = devm_clk_get(dev, "cpts");
776
777 if (IS_ERR(cpts->refclk)) {
778 dev_err(dev, "Failed to get cpts refclk %ld\n",
779 PTR_ERR(cpts->refclk));
780 return ERR_CAST(cpts->refclk);
781 }
782
783 ret = clk_prepare(cpts->refclk);
784 if (ret)
785 return ERR_PTR(ret);
786
787 cpts->cc.read = cpts_systim_read;
788 cpts->cc.mask = CLOCKSOURCE_MASK(32);
789 cpts->info = cpts_info;
790 cpts->phc_index = -1;
791
792 if (n_ext_ts)
793 cpts->info.n_ext_ts = n_ext_ts;
794
795 cpts_calc_mult_shift(cpts);
796 /* save cc.mult original value as it can be modified
797 * by cpts_ptp_adjfreq().
798 */
799 cpts->cc_mult = cpts->cc.mult;
800
801 return cpts;
802 }
803 EXPORT_SYMBOL_GPL(cpts_create);
804
cpts_release(struct cpts * cpts)805 void cpts_release(struct cpts *cpts)
806 {
807 if (!cpts)
808 return;
809
810 if (WARN_ON(!cpts->refclk))
811 return;
812
813 clk_unprepare(cpts->refclk);
814 }
815 EXPORT_SYMBOL_GPL(cpts_release);
816
817 MODULE_LICENSE("GPL v2");
818 MODULE_DESCRIPTION("TI CPTS driver");
819 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
820