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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>");
1/*
2 * TI Common Platform Time Sync
3 *
4 * Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20#include <linux/err.h>
21#include <linux/if.h>
22#include <linux/hrtimer.h>
23#include <linux/module.h>
24#include <linux/net_tstamp.h>
25#include <linux/ptp_classify.h>
26#include <linux/time.h>
27#include <linux/uaccess.h>
28#include <linux/workqueue.h>
29#include <linux/if_ether.h>
30#include <linux/if_vlan.h>
31
32#include "cpts.h"
33
34#define cpts_read32(c, r) readl_relaxed(&c->reg->r)
35#define cpts_write32(c, v, r) writel_relaxed(v, &c->reg->r)
36
37static int event_expired(struct cpts_event *event)
38{
39 return time_after(jiffies, event->tmo);
40}
41
42static int event_type(struct cpts_event *event)
43{
44 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
45}
46
47static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
48{
49 u32 r = cpts_read32(cpts, intstat_raw);
50
51 if (r & TS_PEND_RAW) {
52 *high = cpts_read32(cpts, event_high);
53 *low = cpts_read32(cpts, event_low);
54 cpts_write32(cpts, EVENT_POP, event_pop);
55 return 0;
56 }
57 return -1;
58}
59
60static int cpts_purge_events(struct cpts *cpts)
61{
62 struct list_head *this, *next;
63 struct cpts_event *event;
64 int removed = 0;
65
66 list_for_each_safe(this, next, &cpts->events) {
67 event = list_entry(this, struct cpts_event, list);
68 if (event_expired(event)) {
69 list_del_init(&event->list);
70 list_add(&event->list, &cpts->pool);
71 ++removed;
72 }
73 }
74
75 if (removed)
76 pr_debug("cpts: event pool cleaned up %d\n", removed);
77 return removed ? 0 : -1;
78}
79
80/*
81 * Returns zero if matching event type was found.
82 */
83static int cpts_fifo_read(struct cpts *cpts, int match)
84{
85 int i, type = -1;
86 u32 hi, lo;
87 struct cpts_event *event;
88
89 for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
90 if (cpts_fifo_pop(cpts, &hi, &lo))
91 break;
92
93 if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
94 pr_err("cpts: event pool empty\n");
95 return -1;
96 }
97
98 event = list_first_entry(&cpts->pool, struct cpts_event, list);
99 event->tmo = jiffies + 2;
100 event->high = hi;
101 event->low = lo;
102 type = event_type(event);
103 switch (type) {
104 case CPTS_EV_PUSH:
105 case CPTS_EV_RX:
106 case CPTS_EV_TX:
107 list_del_init(&event->list);
108 list_add_tail(&event->list, &cpts->events);
109 break;
110 case CPTS_EV_ROLL:
111 case CPTS_EV_HALF:
112 case CPTS_EV_HW:
113 break;
114 default:
115 pr_err("cpts: unknown event type\n");
116 break;
117 }
118 if (type == match)
119 break;
120 }
121 return type == match ? 0 : -1;
122}
123
124static u64 cpts_systim_read(const struct cyclecounter *cc)
125{
126 u64 val = 0;
127 struct cpts_event *event;
128 struct list_head *this, *next;
129 struct cpts *cpts = container_of(cc, struct cpts, cc);
130
131 cpts_write32(cpts, TS_PUSH, ts_push);
132 if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
133 pr_err("cpts: unable to obtain a time stamp\n");
134
135 list_for_each_safe(this, next, &cpts->events) {
136 event = list_entry(this, struct cpts_event, list);
137 if (event_type(event) == CPTS_EV_PUSH) {
138 list_del_init(&event->list);
139 list_add(&event->list, &cpts->pool);
140 val = event->low;
141 break;
142 }
143 }
144
145 return val;
146}
147
148/* PTP clock operations */
149
150static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
151{
152 u64 adj;
153 u32 diff, mult;
154 int neg_adj = 0;
155 unsigned long flags;
156 struct cpts *cpts = container_of(ptp, struct cpts, info);
157
158 if (ppb < 0) {
159 neg_adj = 1;
160 ppb = -ppb;
161 }
162 mult = cpts->cc_mult;
163 adj = mult;
164 adj *= ppb;
165 diff = div_u64(adj, 1000000000ULL);
166
167 spin_lock_irqsave(&cpts->lock, flags);
168
169 timecounter_read(&cpts->tc);
170
171 cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
172
173 spin_unlock_irqrestore(&cpts->lock, flags);
174
175 return 0;
176}
177
178static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
179{
180 unsigned long flags;
181 struct cpts *cpts = container_of(ptp, struct cpts, info);
182
183 spin_lock_irqsave(&cpts->lock, flags);
184 timecounter_adjtime(&cpts->tc, delta);
185 spin_unlock_irqrestore(&cpts->lock, flags);
186
187 return 0;
188}
189
190static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
191{
192 u64 ns;
193 unsigned long flags;
194 struct cpts *cpts = container_of(ptp, struct cpts, info);
195
196 spin_lock_irqsave(&cpts->lock, flags);
197 ns = timecounter_read(&cpts->tc);
198 spin_unlock_irqrestore(&cpts->lock, flags);
199
200 *ts = ns_to_timespec64(ns);
201
202 return 0;
203}
204
205static int cpts_ptp_settime(struct ptp_clock_info *ptp,
206 const struct timespec64 *ts)
207{
208 u64 ns;
209 unsigned long flags;
210 struct cpts *cpts = container_of(ptp, struct cpts, info);
211
212 ns = timespec64_to_ns(ts);
213
214 spin_lock_irqsave(&cpts->lock, flags);
215 timecounter_init(&cpts->tc, &cpts->cc, ns);
216 spin_unlock_irqrestore(&cpts->lock, flags);
217
218 return 0;
219}
220
221static int cpts_ptp_enable(struct ptp_clock_info *ptp,
222 struct ptp_clock_request *rq, int on)
223{
224 return -EOPNOTSUPP;
225}
226
227static struct ptp_clock_info cpts_info = {
228 .owner = THIS_MODULE,
229 .name = "CTPS timer",
230 .max_adj = 1000000,
231 .n_ext_ts = 0,
232 .n_pins = 0,
233 .pps = 0,
234 .adjfreq = cpts_ptp_adjfreq,
235 .adjtime = cpts_ptp_adjtime,
236 .gettime64 = cpts_ptp_gettime,
237 .settime64 = cpts_ptp_settime,
238 .enable = cpts_ptp_enable,
239};
240
241static void cpts_overflow_check(struct work_struct *work)
242{
243 struct timespec64 ts;
244 struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
245
246 cpts_ptp_gettime(&cpts->info, &ts);
247 pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
248 schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
249}
250
251static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
252 u16 ts_seqid, u8 ts_msgtype)
253{
254 u16 *seqid;
255 unsigned int offset = 0;
256 u8 *msgtype, *data = skb->data;
257
258 if (ptp_class & PTP_CLASS_VLAN)
259 offset += VLAN_HLEN;
260
261 switch (ptp_class & PTP_CLASS_PMASK) {
262 case PTP_CLASS_IPV4:
263 offset += ETH_HLEN + IPV4_HLEN(data + offset) + UDP_HLEN;
264 break;
265 case PTP_CLASS_IPV6:
266 offset += ETH_HLEN + IP6_HLEN + UDP_HLEN;
267 break;
268 case PTP_CLASS_L2:
269 offset += ETH_HLEN;
270 break;
271 default:
272 return 0;
273 }
274
275 if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid))
276 return 0;
277
278 if (unlikely(ptp_class & PTP_CLASS_V1))
279 msgtype = data + offset + OFF_PTP_CONTROL;
280 else
281 msgtype = data + offset;
282
283 seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
284
285 return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
286}
287
288static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
289{
290 u64 ns = 0;
291 struct cpts_event *event;
292 struct list_head *this, *next;
293 unsigned int class = ptp_classify_raw(skb);
294 unsigned long flags;
295 u16 seqid;
296 u8 mtype;
297
298 if (class == PTP_CLASS_NONE)
299 return 0;
300
301 spin_lock_irqsave(&cpts->lock, flags);
302 cpts_fifo_read(cpts, CPTS_EV_PUSH);
303 list_for_each_safe(this, next, &cpts->events) {
304 event = list_entry(this, struct cpts_event, list);
305 if (event_expired(event)) {
306 list_del_init(&event->list);
307 list_add(&event->list, &cpts->pool);
308 continue;
309 }
310 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
311 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
312 if (ev_type == event_type(event) &&
313 cpts_match(skb, class, seqid, mtype)) {
314 ns = timecounter_cyc2time(&cpts->tc, event->low);
315 list_del_init(&event->list);
316 list_add(&event->list, &cpts->pool);
317 break;
318 }
319 }
320 spin_unlock_irqrestore(&cpts->lock, flags);
321
322 return ns;
323}
324
325void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
326{
327 u64 ns;
328 struct skb_shared_hwtstamps *ssh;
329
330 if (!cpts->rx_enable)
331 return;
332 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
333 if (!ns)
334 return;
335 ssh = skb_hwtstamps(skb);
336 memset(ssh, 0, sizeof(*ssh));
337 ssh->hwtstamp = ns_to_ktime(ns);
338}
339EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
340
341void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
342{
343 u64 ns;
344 struct skb_shared_hwtstamps ssh;
345
346 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
347 return;
348 ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
349 if (!ns)
350 return;
351 memset(&ssh, 0, sizeof(ssh));
352 ssh.hwtstamp = ns_to_ktime(ns);
353 skb_tstamp_tx(skb, &ssh);
354}
355EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
356
357int cpts_register(struct cpts *cpts)
358{
359 int err, i;
360
361 INIT_LIST_HEAD(&cpts->events);
362 INIT_LIST_HEAD(&cpts->pool);
363 for (i = 0; i < CPTS_MAX_EVENTS; i++)
364 list_add(&cpts->pool_data[i].list, &cpts->pool);
365
366 clk_enable(cpts->refclk);
367
368 cpts_write32(cpts, CPTS_EN, control);
369 cpts_write32(cpts, TS_PEND_EN, int_enable);
370
371 timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
372
373 cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
374 if (IS_ERR(cpts->clock)) {
375 err = PTR_ERR(cpts->clock);
376 cpts->clock = NULL;
377 goto err_ptp;
378 }
379 cpts->phc_index = ptp_clock_index(cpts->clock);
380
381 schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
382 return 0;
383
384err_ptp:
385 clk_disable(cpts->refclk);
386 return err;
387}
388EXPORT_SYMBOL_GPL(cpts_register);
389
390void cpts_unregister(struct cpts *cpts)
391{
392 if (WARN_ON(!cpts->clock))
393 return;
394
395 cancel_delayed_work_sync(&cpts->overflow_work);
396
397 ptp_clock_unregister(cpts->clock);
398 cpts->clock = NULL;
399
400 cpts_write32(cpts, 0, int_enable);
401 cpts_write32(cpts, 0, control);
402
403 clk_disable(cpts->refclk);
404}
405EXPORT_SYMBOL_GPL(cpts_unregister);
406
407static void cpts_calc_mult_shift(struct cpts *cpts)
408{
409 u64 frac, maxsec, ns;
410 u32 freq;
411
412 freq = clk_get_rate(cpts->refclk);
413
414 /* Calc the maximum number of seconds which we can run before
415 * wrapping around.
416 */
417 maxsec = cpts->cc.mask;
418 do_div(maxsec, freq);
419 /* limit conversation rate to 10 sec as higher values will produce
420 * too small mult factors and so reduce the conversion accuracy
421 */
422 if (maxsec > 10)
423 maxsec = 10;
424
425 /* Calc overflow check period (maxsec / 2) */
426 cpts->ov_check_period = (HZ * maxsec) / 2;
427 dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
428 cpts->ov_check_period);
429
430 if (cpts->cc.mult || cpts->cc.shift)
431 return;
432
433 clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
434 freq, NSEC_PER_SEC, maxsec);
435
436 frac = 0;
437 ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
438
439 dev_info(cpts->dev,
440 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
441 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
442}
443
444static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
445{
446 int ret = -EINVAL;
447 u32 prop;
448
449 if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
450 cpts->cc.mult = prop;
451
452 if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
453 cpts->cc.shift = prop;
454
455 if ((cpts->cc.mult && !cpts->cc.shift) ||
456 (!cpts->cc.mult && cpts->cc.shift))
457 goto of_error;
458
459 return 0;
460
461of_error:
462 dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
463 return ret;
464}
465
466struct cpts *cpts_create(struct device *dev, void __iomem *regs,
467 struct device_node *node)
468{
469 struct cpts *cpts;
470 int ret;
471
472 cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
473 if (!cpts)
474 return ERR_PTR(-ENOMEM);
475
476 cpts->dev = dev;
477 cpts->reg = (struct cpsw_cpts __iomem *)regs;
478 spin_lock_init(&cpts->lock);
479 INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
480
481 ret = cpts_of_parse(cpts, node);
482 if (ret)
483 return ERR_PTR(ret);
484
485 cpts->refclk = devm_clk_get(dev, "cpts");
486 if (IS_ERR(cpts->refclk)) {
487 dev_err(dev, "Failed to get cpts refclk\n");
488 return ERR_PTR(PTR_ERR(cpts->refclk));
489 }
490
491 clk_prepare(cpts->refclk);
492
493 cpts->cc.read = cpts_systim_read;
494 cpts->cc.mask = CLOCKSOURCE_MASK(32);
495 cpts->info = cpts_info;
496
497 cpts_calc_mult_shift(cpts);
498 /* save cc.mult original value as it can be modified
499 * by cpts_ptp_adjfreq().
500 */
501 cpts->cc_mult = cpts->cc.mult;
502
503 return cpts;
504}
505EXPORT_SYMBOL_GPL(cpts_create);
506
507void cpts_release(struct cpts *cpts)
508{
509 if (!cpts)
510 return;
511
512 if (WARN_ON(!cpts->refclk))
513 return;
514
515 clk_unprepare(cpts->refclk);
516}
517EXPORT_SYMBOL_GPL(cpts_release);
518
519MODULE_LICENSE("GPL v2");
520MODULE_DESCRIPTION("TI CPTS driver");
521MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");