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gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / net / ethernet / ti / cpts.c
blob729ce09dded9f26edf9f68629151a65041747a71
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
25 struct cpts_skb_cb_data {
26 unsigned long tmo;
27 };
28
29 #define cpts_read32(c, r) readl_relaxed(&c->reg->r)
30 #define cpts_write32(c, v, r) writel_relaxed(v, &c->reg->r)
31
32 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
33 u16 ts_seqid, u8 ts_msgtype);
34
35 static int event_expired(struct cpts_event *event)
36 {
37 return time_after(jiffies, event->tmo);
38 }
39
40 static int event_type(struct cpts_event *event)
41 {
42 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
43 }
44
45 static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
46 {
47 u32 r = cpts_read32(cpts, intstat_raw);
48
49 if (r & TS_PEND_RAW) {
50 *high = cpts_read32(cpts, event_high);
51 *low = cpts_read32(cpts, event_low);
52 cpts_write32(cpts, EVENT_POP, event_pop);
53 return 0;
54 }
55 return -1;
56 }
57
58 static int cpts_purge_events(struct cpts *cpts)
59 {
60 struct list_head *this, *next;
61 struct cpts_event *event;
62 int removed = 0;
63
64 list_for_each_safe(this, next, &cpts->events) {
65 event = list_entry(this, struct cpts_event, list);
66 if (event_expired(event)) {
67 list_del_init(&event->list);
68 list_add(&event->list, &cpts->pool);
69 ++removed;
70 }
71 }
72
73 if (removed)
74 pr_debug("cpts: event pool cleaned up %d\n", removed);
75 return removed ? 0 : -1;
76 }
77
78 static void cpts_purge_txq(struct cpts *cpts)
79 {
80 struct cpts_skb_cb_data *skb_cb;
81 struct sk_buff *skb, *tmp;
82 int removed = 0;
83
84 skb_queue_walk_safe(&cpts->txq, skb, tmp) {
85 skb_cb = (struct cpts_skb_cb_data *)skb->cb;
86 if (time_after(jiffies, skb_cb->tmo)) {
87 __skb_unlink(skb, &cpts->txq);
88 dev_consume_skb_any(skb);
89 ++removed;
90 }
91 }
92
93 if (removed)
94 dev_dbg(cpts->dev, "txq cleaned up %d\n", removed);
95 }
96
97 static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
98 {
99 struct sk_buff *skb, *tmp;
100 u16 seqid;
101 u8 mtype;
102 bool found = false;
103
104 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
105 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
106
107 /* no need to grab txq.lock as access is always done under cpts->lock */
108 skb_queue_walk_safe(&cpts->txq, skb, tmp) {
109 struct skb_shared_hwtstamps ssh;
110 unsigned int class = ptp_classify_raw(skb);
111 struct cpts_skb_cb_data *skb_cb =
112 (struct cpts_skb_cb_data *)skb->cb;
113
114 if (cpts_match(skb, class, seqid, mtype)) {
115 u64 ns = timecounter_cyc2time(&cpts->tc, event->low);
116
117 memset(&ssh, 0, sizeof(ssh));
118 ssh.hwtstamp = ns_to_ktime(ns);
119 skb_tstamp_tx(skb, &ssh);
120 found = true;
121 __skb_unlink(skb, &cpts->txq);
122 dev_consume_skb_any(skb);
123 dev_dbg(cpts->dev, "match tx timestamp mtype %u seqid %04x\n",
124 mtype, seqid);
125 break;
126 }
127
128 if (time_after(jiffies, skb_cb->tmo)) {
129 /* timeout any expired skbs over 1s */
130 dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
131 __skb_unlink(skb, &cpts->txq);
132 dev_consume_skb_any(skb);
133 }
134 }
135
136 return found;
137 }
138
139 /*
140 * Returns zero if matching event type was found.
141 */
142 static int cpts_fifo_read(struct cpts *cpts, int match)
143 {
144 int i, type = -1;
145 u32 hi, lo;
146 struct cpts_event *event;
147
148 for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
149 if (cpts_fifo_pop(cpts, &hi, &lo))
150 break;
151
152 if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
153 pr_err("cpts: event pool empty\n");
154 return -1;
155 }
156
157 event = list_first_entry(&cpts->pool, struct cpts_event, list);
158 event->tmo = jiffies + 2;
159 event->high = hi;
160 event->low = lo;
161 type = event_type(event);
162 switch (type) {
163 case CPTS_EV_TX:
164 if (cpts_match_tx_ts(cpts, event)) {
165 /* if the new event matches an existing skb,
166 * then don't queue it
167 */
168 break;
169 }
170 /* fall through */
171 case CPTS_EV_PUSH:
172 case CPTS_EV_RX:
173 list_del_init(&event->list);
174 list_add_tail(&event->list, &cpts->events);
175 break;
176 case CPTS_EV_ROLL:
177 case CPTS_EV_HALF:
178 case CPTS_EV_HW:
179 break;
180 default:
181 pr_err("cpts: unknown event type\n");
182 break;
183 }
184 if (type == match)
185 break;
186 }
187 return type == match ? 0 : -1;
188 }
189
190 static u64 cpts_systim_read(const struct cyclecounter *cc)
191 {
192 u64 val = 0;
193 struct cpts_event *event;
194 struct list_head *this, *next;
195 struct cpts *cpts = container_of(cc, struct cpts, cc);
196
197 cpts_write32(cpts, TS_PUSH, ts_push);
198 if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
199 pr_err("cpts: unable to obtain a time stamp\n");
200
201 list_for_each_safe(this, next, &cpts->events) {
202 event = list_entry(this, struct cpts_event, list);
203 if (event_type(event) == CPTS_EV_PUSH) {
204 list_del_init(&event->list);
205 list_add(&event->list, &cpts->pool);
206 val = event->low;
207 break;
208 }
209 }
210
211 return val;
212 }
213
214 /* PTP clock operations */
215
216 static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
217 {
218 u64 adj;
219 u32 diff, mult;
220 int neg_adj = 0;
221 unsigned long flags;
222 struct cpts *cpts = container_of(ptp, struct cpts, info);
223
224 if (ppb < 0) {
225 neg_adj = 1;
226 ppb = -ppb;
227 }
228 mult = cpts->cc_mult;
229 adj = mult;
230 adj *= ppb;
231 diff = div_u64(adj, 1000000000ULL);
232
233 spin_lock_irqsave(&cpts->lock, flags);
234
235 timecounter_read(&cpts->tc);
236
237 cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
238
239 spin_unlock_irqrestore(&cpts->lock, flags);
240
241 return 0;
242 }
243
244 static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
245 {
246 unsigned long flags;
247 struct cpts *cpts = container_of(ptp, struct cpts, info);
248
249 spin_lock_irqsave(&cpts->lock, flags);
250 timecounter_adjtime(&cpts->tc, delta);
251 spin_unlock_irqrestore(&cpts->lock, flags);
252
253 return 0;
254 }
255
256 static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
257 {
258 u64 ns;
259 unsigned long flags;
260 struct cpts *cpts = container_of(ptp, struct cpts, info);
261
262 spin_lock_irqsave(&cpts->lock, flags);
263 ns = timecounter_read(&cpts->tc);
264 spin_unlock_irqrestore(&cpts->lock, flags);
265
266 *ts = ns_to_timespec64(ns);
267
268 return 0;
269 }
270
271 static int cpts_ptp_settime(struct ptp_clock_info *ptp,
272 const struct timespec64 *ts)
273 {
274 u64 ns;
275 unsigned long flags;
276 struct cpts *cpts = container_of(ptp, struct cpts, info);
277
278 ns = timespec64_to_ns(ts);
279
280 spin_lock_irqsave(&cpts->lock, flags);
281 timecounter_init(&cpts->tc, &cpts->cc, ns);
282 spin_unlock_irqrestore(&cpts->lock, flags);
283
284 return 0;
285 }
286
287 static int cpts_ptp_enable(struct ptp_clock_info *ptp,
288 struct ptp_clock_request *rq, int on)
289 {
290 return -EOPNOTSUPP;
291 }
292
293 static long cpts_overflow_check(struct ptp_clock_info *ptp)
294 {
295 struct cpts *cpts = container_of(ptp, struct cpts, info);
296 unsigned long delay = cpts->ov_check_period;
297 struct timespec64 ts;
298 unsigned long flags;
299
300 spin_lock_irqsave(&cpts->lock, flags);
301 ts = ns_to_timespec64(timecounter_read(&cpts->tc));
302
303 if (!skb_queue_empty(&cpts->txq)) {
304 cpts_purge_txq(cpts);
305 if (!skb_queue_empty(&cpts->txq))
306 delay = CPTS_SKB_TX_WORK_TIMEOUT;
307 }
308 spin_unlock_irqrestore(&cpts->lock, flags);
309
310 pr_debug("cpts overflow check at %lld.%09ld\n",
311 (long long)ts.tv_sec, ts.tv_nsec);
312 return (long)delay;
313 }
314
315 static const struct ptp_clock_info cpts_info = {
316 .owner = THIS_MODULE,
317 .name = "CTPS timer",
318 .max_adj = 1000000,
319 .n_ext_ts = 0,
320 .n_pins = 0,
321 .pps = 0,
322 .adjfreq = cpts_ptp_adjfreq,
323 .adjtime = cpts_ptp_adjtime,
324 .gettime64 = cpts_ptp_gettime,
325 .settime64 = cpts_ptp_settime,
326 .enable = cpts_ptp_enable,
327 .do_aux_work = cpts_overflow_check,
328 };
329
330 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
331 u16 ts_seqid, u8 ts_msgtype)
332 {
333 u16 *seqid;
334 unsigned int offset = 0;
335 u8 *msgtype, *data = skb->data;
336
337 if (ptp_class & PTP_CLASS_VLAN)
338 offset += VLAN_HLEN;
339
340 switch (ptp_class & PTP_CLASS_PMASK) {
341 case PTP_CLASS_IPV4:
342 offset += ETH_HLEN + IPV4_HLEN(data + offset) + UDP_HLEN;
343 break;
344 case PTP_CLASS_IPV6:
345 offset += ETH_HLEN + IP6_HLEN + UDP_HLEN;
346 break;
347 case PTP_CLASS_L2:
348 offset += ETH_HLEN;
349 break;
350 default:
351 return 0;
352 }
353
354 if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid))
355 return 0;
356
357 if (unlikely(ptp_class & PTP_CLASS_V1))
358 msgtype = data + offset + OFF_PTP_CONTROL;
359 else
360 msgtype = data + offset;
361
362 seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
363
364 return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
365 }
366
367 static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
368 {
369 u64 ns = 0;
370 struct cpts_event *event;
371 struct list_head *this, *next;
372 unsigned int class = ptp_classify_raw(skb);
373 unsigned long flags;
374 u16 seqid;
375 u8 mtype;
376
377 if (class == PTP_CLASS_NONE)
378 return 0;
379
380 spin_lock_irqsave(&cpts->lock, flags);
381 cpts_fifo_read(cpts, -1);
382 list_for_each_safe(this, next, &cpts->events) {
383 event = list_entry(this, struct cpts_event, list);
384 if (event_expired(event)) {
385 list_del_init(&event->list);
386 list_add(&event->list, &cpts->pool);
387 continue;
388 }
389 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
390 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
391 if (ev_type == event_type(event) &&
392 cpts_match(skb, class, seqid, mtype)) {
393 ns = timecounter_cyc2time(&cpts->tc, event->low);
394 list_del_init(&event->list);
395 list_add(&event->list, &cpts->pool);
396 break;
397 }
398 }
399
400 if (ev_type == CPTS_EV_TX && !ns) {
401 struct cpts_skb_cb_data *skb_cb =
402 (struct cpts_skb_cb_data *)skb->cb;
403 /* Not found, add frame to queue for processing later.
404 * The periodic FIFO check will handle this.
405 */
406 skb_get(skb);
407 /* get the timestamp for timeouts */
408 skb_cb->tmo = jiffies + msecs_to_jiffies(100);
409 __skb_queue_tail(&cpts->txq, skb);
410 ptp_schedule_worker(cpts->clock, 0);
411 }
412 spin_unlock_irqrestore(&cpts->lock, flags);
413
414 return ns;
415 }
416
417 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
418 {
419 u64 ns;
420 struct skb_shared_hwtstamps *ssh;
421
422 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
423 if (!ns)
424 return;
425 ssh = skb_hwtstamps(skb);
426 memset(ssh, 0, sizeof(*ssh));
427 ssh->hwtstamp = ns_to_ktime(ns);
428 }
429 EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
430
431 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
432 {
433 u64 ns;
434 struct skb_shared_hwtstamps ssh;
435
436 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
437 return;
438 ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
439 if (!ns)
440 return;
441 memset(&ssh, 0, sizeof(ssh));
442 ssh.hwtstamp = ns_to_ktime(ns);
443 skb_tstamp_tx(skb, &ssh);
444 }
445 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
446
447 int cpts_register(struct cpts *cpts)
448 {
449 int err, i;
450
451 skb_queue_head_init(&cpts->txq);
452 INIT_LIST_HEAD(&cpts->events);
453 INIT_LIST_HEAD(&cpts->pool);
454 for (i = 0; i < CPTS_MAX_EVENTS; i++)
455 list_add(&cpts->pool_data[i].list, &cpts->pool);
456
457 clk_enable(cpts->refclk);
458
459 cpts_write32(cpts, CPTS_EN, control);
460 cpts_write32(cpts, TS_PEND_EN, int_enable);
461
462 timecounter_init(&cpts->tc, &cpts->cc, ktime_get_real_ns());
463
464 cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
465 if (IS_ERR(cpts->clock)) {
466 err = PTR_ERR(cpts->clock);
467 cpts->clock = NULL;
468 goto err_ptp;
469 }
470 cpts->phc_index = ptp_clock_index(cpts->clock);
471
472 ptp_schedule_worker(cpts->clock, cpts->ov_check_period);
473 return 0;
474
475 err_ptp:
476 clk_disable(cpts->refclk);
477 return err;
478 }
479 EXPORT_SYMBOL_GPL(cpts_register);
480
481 void cpts_unregister(struct cpts *cpts)
482 {
483 if (WARN_ON(!cpts->clock))
484 return;
485
486 ptp_clock_unregister(cpts->clock);
487 cpts->clock = NULL;
488
489 cpts_write32(cpts, 0, int_enable);
490 cpts_write32(cpts, 0, control);
491
492 /* Drop all packet */
493 skb_queue_purge(&cpts->txq);
494
495 clk_disable(cpts->refclk);
496 }
497 EXPORT_SYMBOL_GPL(cpts_unregister);
498
499 static void cpts_calc_mult_shift(struct cpts *cpts)
500 {
501 u64 frac, maxsec, ns;
502 u32 freq;
503
504 freq = clk_get_rate(cpts->refclk);
505
506 /* Calc the maximum number of seconds which we can run before
507 * wrapping around.
508 */
509 maxsec = cpts->cc.mask;
510 do_div(maxsec, freq);
511 /* limit conversation rate to 10 sec as higher values will produce
512 * too small mult factors and so reduce the conversion accuracy
513 */
514 if (maxsec > 10)
515 maxsec = 10;
516
517 /* Calc overflow check period (maxsec / 2) */
518 cpts->ov_check_period = (HZ * maxsec) / 2;
519 dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
520 cpts->ov_check_period);
521
522 if (cpts->cc.mult || cpts->cc.shift)
523 return;
524
525 clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
526 freq, NSEC_PER_SEC, maxsec);
527
528 frac = 0;
529 ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
530
531 dev_info(cpts->dev,
532 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
533 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
534 }
535
536 static int cpts_of_mux_clk_setup(struct cpts *cpts, struct device_node *node)
537 {
538 struct device_node *refclk_np;
539 const char **parent_names;
540 unsigned int num_parents;
541 struct clk_hw *clk_hw;
542 int ret = -EINVAL;
543 u32 *mux_table;
544
545 refclk_np = of_get_child_by_name(node, "cpts-refclk-mux");
546 if (!refclk_np)
547 /* refclk selection supported not for all SoCs */
548 return 0;
549
550 num_parents = of_clk_get_parent_count(refclk_np);
551 if (num_parents < 1) {
552 dev_err(cpts->dev, "mux-clock %s must have parents\n",
553 refclk_np->name);
554 goto mux_fail;
555 }
556
557 parent_names = devm_kzalloc(cpts->dev, (sizeof(char *) * num_parents),
558 GFP_KERNEL);
559
560 mux_table = devm_kzalloc(cpts->dev, sizeof(*mux_table) * num_parents,
561 GFP_KERNEL);
562 if (!mux_table || !parent_names) {
563 ret = -ENOMEM;
564 goto mux_fail;
565 }
566
567 of_clk_parent_fill(refclk_np, parent_names, num_parents);
568
569 ret = of_property_read_variable_u32_array(refclk_np, "ti,mux-tbl",
570 mux_table,
571 num_parents, num_parents);
572 if (ret < 0)
573 goto mux_fail;
574
575 clk_hw = clk_hw_register_mux_table(cpts->dev, refclk_np->name,
576 parent_names, num_parents,
577 0,
578 &cpts->reg->rftclk_sel, 0, 0x1F,
579 0, mux_table, NULL);
580 if (IS_ERR(clk_hw)) {
581 ret = PTR_ERR(clk_hw);
582 goto mux_fail;
583 }
584
585 ret = devm_add_action_or_reset(cpts->dev,
586 (void(*)(void *))clk_hw_unregister_mux,
587 clk_hw);
588 if (ret) {
589 dev_err(cpts->dev, "add clkmux unreg action %d", ret);
590 goto mux_fail;
591 }
592
593 ret = of_clk_add_hw_provider(refclk_np, of_clk_hw_simple_get, clk_hw);
594 if (ret)
595 goto mux_fail;
596
597 ret = devm_add_action_or_reset(cpts->dev,
598 (void(*)(void *))of_clk_del_provider,
599 refclk_np);
600 if (ret) {
601 dev_err(cpts->dev, "add clkmux provider unreg action %d", ret);
602 goto mux_fail;
603 }
604
605 return ret;
606
607 mux_fail:
608 of_node_put(refclk_np);
609 return ret;
610 }
611
612 static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
613 {
614 int ret = -EINVAL;
615 u32 prop;
616
617 if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
618 cpts->cc.mult = prop;
619
620 if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
621 cpts->cc.shift = prop;
622
623 if ((cpts->cc.mult && !cpts->cc.shift) ||
624 (!cpts->cc.mult && cpts->cc.shift))
625 goto of_error;
626
627 return cpts_of_mux_clk_setup(cpts, node);
628
629 of_error:
630 dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
631 return ret;
632 }
633
634 struct cpts *cpts_create(struct device *dev, void __iomem *regs,
635 struct device_node *node)
636 {
637 struct cpts *cpts;
638 int ret;
639
640 cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
641 if (!cpts)
642 return ERR_PTR(-ENOMEM);
643
644 cpts->dev = dev;
645 cpts->reg = (struct cpsw_cpts __iomem *)regs;
646 spin_lock_init(&cpts->lock);
647
648 ret = cpts_of_parse(cpts, node);
649 if (ret)
650 return ERR_PTR(ret);
651
652 cpts->refclk = devm_get_clk_from_child(dev, node, "cpts");
653 if (IS_ERR(cpts->refclk))
654 /* try get clk from dev node for compatibility */
655 cpts->refclk = devm_clk_get(dev, "cpts");
656
657 if (IS_ERR(cpts->refclk)) {
658 dev_err(dev, "Failed to get cpts refclk %ld\n",
659 PTR_ERR(cpts->refclk));
660 return ERR_CAST(cpts->refclk);
661 }
662
663 ret = clk_prepare(cpts->refclk);
664 if (ret)
665 return ERR_PTR(ret);
666
667 cpts->cc.read = cpts_systim_read;
668 cpts->cc.mask = CLOCKSOURCE_MASK(32);
669 cpts->info = cpts_info;
670
671 cpts_calc_mult_shift(cpts);
672 /* save cc.mult original value as it can be modified
673 * by cpts_ptp_adjfreq().
674 */
675 cpts->cc_mult = cpts->cc.mult;
676
677 return cpts;
678 }
679 EXPORT_SYMBOL_GPL(cpts_create);
680
681 void cpts_release(struct cpts *cpts)
682 {
683 if (!cpts)
684 return;
685
686 if (WARN_ON(!cpts->refclk))
687 return;
688
689 clk_unprepare(cpts->refclk);
690 }
691 EXPORT_SYMBOL_GPL(cpts_release);
692
693 MODULE_LICENSE("GPL v2");
694 MODULE_DESCRIPTION("TI CPTS driver");
695 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
Linux with added FPC-III support