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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_SKB_TX_WORK_TIMEOUT 1
35
36struct cpts_skb_cb_data {
37 unsigned long tmo;
38};
39
40#define cpts_read32(c, r) readl_relaxed(&c->reg->r)
41#define cpts_write32(c, v, r) writel_relaxed(v, &c->reg->r)
42
43static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
44 u16 ts_seqid, u8 ts_msgtype);
45
46static int event_expired(struct cpts_event *event)
47{
48 return time_after(jiffies, event->tmo);
49}
50
51static int event_type(struct cpts_event *event)
52{
53 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
54}
55
56static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
57{
58 u32 r = cpts_read32(cpts, intstat_raw);
59
60 if (r & TS_PEND_RAW) {
61 *high = cpts_read32(cpts, event_high);
62 *low = cpts_read32(cpts, event_low);
63 cpts_write32(cpts, EVENT_POP, event_pop);
64 return 0;
65 }
66 return -1;
67}
68
69static int cpts_purge_events(struct cpts *cpts)
70{
71 struct list_head *this, *next;
72 struct cpts_event *event;
73 int removed = 0;
74
75 list_for_each_safe(this, next, &cpts->events) {
76 event = list_entry(this, struct cpts_event, list);
77 if (event_expired(event)) {
78 list_del_init(&event->list);
79 list_add(&event->list, &cpts->pool);
80 ++removed;
81 }
82 }
83
84 if (removed)
85 pr_debug("cpts: event pool cleaned up %d\n", removed);
86 return removed ? 0 : -1;
87}
88
89static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
90{
91 struct sk_buff *skb, *tmp;
92 u16 seqid;
93 u8 mtype;
94 bool found = false;
95
96 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
97 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
98
99
100 skb_queue_walk_safe(&cpts->txq, skb, tmp) {
101 struct skb_shared_hwtstamps ssh;
102 unsigned int class = ptp_classify_raw(skb);
103 struct cpts_skb_cb_data *skb_cb =
104 (struct cpts_skb_cb_data *)skb->cb;
105
106 if (cpts_match(skb, class, seqid, mtype)) {
107 u64 ns = timecounter_cyc2time(&cpts->tc, event->low);
108
109 memset(&ssh, 0, sizeof(ssh));
110 ssh.hwtstamp = ns_to_ktime(ns);
111 skb_tstamp_tx(skb, &ssh);
112 found = true;
113 __skb_unlink(skb, &cpts->txq);
114 dev_consume_skb_any(skb);
115 dev_dbg(cpts->dev, "match tx timestamp mtype %u seqid %04x\n",
116 mtype, seqid);
117 } else if (time_after(jiffies, skb_cb->tmo)) {
118
119 dev_dbg(cpts->dev,
120 "expiring tx timestamp mtype %u seqid %04x\n",
121 mtype, seqid);
122 __skb_unlink(skb, &cpts->txq);
123 dev_consume_skb_any(skb);
124 }
125 }
126
127 return found;
128}
129
130
131
132
133static int cpts_fifo_read(struct cpts *cpts, int match)
134{
135 int i, type = -1;
136 u32 hi, lo;
137 struct cpts_event *event;
138
139 for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
140 if (cpts_fifo_pop(cpts, &hi, &lo))
141 break;
142
143 if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
144 pr_err("cpts: event pool empty\n");
145 return -1;
146 }
147
148 event = list_first_entry(&cpts->pool, struct cpts_event, list);
149 event->tmo = jiffies + 2;
150 event->high = hi;
151 event->low = lo;
152 type = event_type(event);
153 switch (type) {
154 case CPTS_EV_TX:
155 if (cpts_match_tx_ts(cpts, event)) {
156
157
158
159 break;
160 }
161 case CPTS_EV_PUSH:
162 case CPTS_EV_RX:
163 list_del_init(&event->list);
164 list_add_tail(&event->list, &cpts->events);
165 break;
166 case CPTS_EV_ROLL:
167 case CPTS_EV_HALF:
168 case CPTS_EV_HW:
169 break;
170 default:
171 pr_err("cpts: unknown event type\n");
172 break;
173 }
174 if (type == match)
175 break;
176 }
177 return type == match ? 0 : -1;
178}
179
180static u64 cpts_systim_read(const struct cyclecounter *cc)
181{
182 u64 val = 0;
183 struct cpts_event *event;
184 struct list_head *this, *next;
185 struct cpts *cpts = container_of(cc, struct cpts, cc);
186
187 cpts_write32(cpts, TS_PUSH, ts_push);
188 if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
189 pr_err("cpts: unable to obtain a time stamp\n");
190
191 list_for_each_safe(this, next, &cpts->events) {
192 event = list_entry(this, struct cpts_event, list);
193 if (event_type(event) == CPTS_EV_PUSH) {
194 list_del_init(&event->list);
195 list_add(&event->list, &cpts->pool);
196 val = event->low;
197 break;
198 }
199 }
200
201 return val;
202}
203
204
205
206static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
207{
208 u64 adj;
209 u32 diff, mult;
210 int neg_adj = 0;
211 unsigned long flags;
212 struct cpts *cpts = container_of(ptp, struct cpts, info);
213
214 if (ppb < 0) {
215 neg_adj = 1;
216 ppb = -ppb;
217 }
218 mult = cpts->cc_mult;
219 adj = mult;
220 adj *= ppb;
221 diff = div_u64(adj, 1000000000ULL);
222
223 spin_lock_irqsave(&cpts->lock, flags);
224
225 timecounter_read(&cpts->tc);
226
227 cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
228
229 spin_unlock_irqrestore(&cpts->lock, flags);
230
231 return 0;
232}
233
234static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
235{
236 unsigned long flags;
237 struct cpts *cpts = container_of(ptp, struct cpts, info);
238
239 spin_lock_irqsave(&cpts->lock, flags);
240 timecounter_adjtime(&cpts->tc, delta);
241 spin_unlock_irqrestore(&cpts->lock, flags);
242
243 return 0;
244}
245
246static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
247{
248 u64 ns;
249 unsigned long flags;
250 struct cpts *cpts = container_of(ptp, struct cpts, info);
251
252 spin_lock_irqsave(&cpts->lock, flags);
253 ns = timecounter_read(&cpts->tc);
254 spin_unlock_irqrestore(&cpts->lock, flags);
255
256 *ts = ns_to_timespec64(ns);
257
258 return 0;
259}
260
261static int cpts_ptp_settime(struct ptp_clock_info *ptp,
262 const struct timespec64 *ts)
263{
264 u64 ns;
265 unsigned long flags;
266 struct cpts *cpts = container_of(ptp, struct cpts, info);
267
268 ns = timespec64_to_ns(ts);
269
270 spin_lock_irqsave(&cpts->lock, flags);
271 timecounter_init(&cpts->tc, &cpts->cc, ns);
272 spin_unlock_irqrestore(&cpts->lock, flags);
273
274 return 0;
275}
276
277static int cpts_ptp_enable(struct ptp_clock_info *ptp,
278 struct ptp_clock_request *rq, int on)
279{
280 return -EOPNOTSUPP;
281}
282
283static long cpts_overflow_check(struct ptp_clock_info *ptp)
284{
285 struct cpts *cpts = container_of(ptp, struct cpts, info);
286 unsigned long delay = cpts->ov_check_period;
287 struct timespec64 ts;
288 unsigned long flags;
289
290 spin_lock_irqsave(&cpts->lock, flags);
291 ts = ns_to_timespec64(timecounter_read(&cpts->tc));
292
293 if (!skb_queue_empty(&cpts->txq))
294 delay = CPTS_SKB_TX_WORK_TIMEOUT;
295 spin_unlock_irqrestore(&cpts->lock, flags);
296
297 pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
298 return (long)delay;
299}
300
301static const struct ptp_clock_info cpts_info = {
302 .owner = THIS_MODULE,
303 .name = "CTPS timer",
304 .max_adj = 1000000,
305 .n_ext_ts = 0,
306 .n_pins = 0,
307 .pps = 0,
308 .adjfreq = cpts_ptp_adjfreq,
309 .adjtime = cpts_ptp_adjtime,
310 .gettime64 = cpts_ptp_gettime,
311 .settime64 = cpts_ptp_settime,
312 .enable = cpts_ptp_enable,
313 .do_aux_work = cpts_overflow_check,
314};
315
316static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
317 u16 ts_seqid, u8 ts_msgtype)
318{
319 u16 *seqid;
320 unsigned int offset = 0;
321 u8 *msgtype, *data = skb->data;
322
323 if (ptp_class & PTP_CLASS_VLAN)
324 offset += VLAN_HLEN;
325
326 switch (ptp_class & PTP_CLASS_PMASK) {
327 case PTP_CLASS_IPV4:
328 offset += ETH_HLEN + IPV4_HLEN(data + offset) + UDP_HLEN;
329 break;
330 case PTP_CLASS_IPV6:
331 offset += ETH_HLEN + IP6_HLEN + UDP_HLEN;
332 break;
333 case PTP_CLASS_L2:
334 offset += ETH_HLEN;
335 break;
336 default:
337 return 0;
338 }
339
340 if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid))
341 return 0;
342
343 if (unlikely(ptp_class & PTP_CLASS_V1))
344 msgtype = data + offset + OFF_PTP_CONTROL;
345 else
346 msgtype = data + offset;
347
348 seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
349
350 return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
351}
352
353static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
354{
355 u64 ns = 0;
356 struct cpts_event *event;
357 struct list_head *this, *next;
358 unsigned int class = ptp_classify_raw(skb);
359 unsigned long flags;
360 u16 seqid;
361 u8 mtype;
362
363 if (class == PTP_CLASS_NONE)
364 return 0;
365
366 spin_lock_irqsave(&cpts->lock, flags);
367 cpts_fifo_read(cpts, -1);
368 list_for_each_safe(this, next, &cpts->events) {
369 event = list_entry(this, struct cpts_event, list);
370 if (event_expired(event)) {
371 list_del_init(&event->list);
372 list_add(&event->list, &cpts->pool);
373 continue;
374 }
375 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
376 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
377 if (ev_type == event_type(event) &&
378 cpts_match(skb, class, seqid, mtype)) {
379 ns = timecounter_cyc2time(&cpts->tc, event->low);
380 list_del_init(&event->list);
381 list_add(&event->list, &cpts->pool);
382 break;
383 }
384 }
385
386 if (ev_type == CPTS_EV_TX && !ns) {
387 struct cpts_skb_cb_data *skb_cb =
388 (struct cpts_skb_cb_data *)skb->cb;
389
390
391
392 skb_get(skb);
393
394 skb_cb->tmo = jiffies + msecs_to_jiffies(100);
395 __skb_queue_tail(&cpts->txq, skb);
396 ptp_schedule_worker(cpts->clock, 0);
397 }
398 spin_unlock_irqrestore(&cpts->lock, flags);
399
400 return ns;
401}
402
403void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
404{
405 u64 ns;
406 struct skb_shared_hwtstamps *ssh;
407
408 if (!cpts->rx_enable)
409 return;
410 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
411 if (!ns)
412 return;
413 ssh = skb_hwtstamps(skb);
414 memset(ssh, 0, sizeof(*ssh));
415 ssh->hwtstamp = ns_to_ktime(ns);
416}
417EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
418
419void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
420{
421 u64 ns;
422 struct skb_shared_hwtstamps ssh;
423
424 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
425 return;
426 ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
427 if (!ns)
428 return;
429 memset(&ssh, 0, sizeof(ssh));
430 ssh.hwtstamp = ns_to_ktime(ns);
431 skb_tstamp_tx(skb, &ssh);
432}
433EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
434
435int cpts_register(struct cpts *cpts)
436{
437 int err, i;
438
439 skb_queue_head_init(&cpts->txq);
440 INIT_LIST_HEAD(&cpts->events);
441 INIT_LIST_HEAD(&cpts->pool);
442 for (i = 0; i < CPTS_MAX_EVENTS; i++)
443 list_add(&cpts->pool_data[i].list, &cpts->pool);
444
445 clk_enable(cpts->refclk);
446
447 cpts_write32(cpts, CPTS_EN, control);
448 cpts_write32(cpts, TS_PEND_EN, int_enable);
449
450 timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
451
452 cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
453 if (IS_ERR(cpts->clock)) {
454 err = PTR_ERR(cpts->clock);
455 cpts->clock = NULL;
456 goto err_ptp;
457 }
458 cpts->phc_index = ptp_clock_index(cpts->clock);
459
460 ptp_schedule_worker(cpts->clock, cpts->ov_check_period);
461 return 0;
462
463err_ptp:
464 clk_disable(cpts->refclk);
465 return err;
466}
467EXPORT_SYMBOL_GPL(cpts_register);
468
469void cpts_unregister(struct cpts *cpts)
470{
471 if (WARN_ON(!cpts->clock))
472 return;
473
474 ptp_clock_unregister(cpts->clock);
475 cpts->clock = NULL;
476
477 cpts_write32(cpts, 0, int_enable);
478 cpts_write32(cpts, 0, control);
479
480
481 skb_queue_purge(&cpts->txq);
482
483 clk_disable(cpts->refclk);
484}
485EXPORT_SYMBOL_GPL(cpts_unregister);
486
487static void cpts_calc_mult_shift(struct cpts *cpts)
488{
489 u64 frac, maxsec, ns;
490 u32 freq;
491
492 freq = clk_get_rate(cpts->refclk);
493
494
495
496
497 maxsec = cpts->cc.mask;
498 do_div(maxsec, freq);
499
500
501
502 if (maxsec > 10)
503 maxsec = 10;
504
505
506 cpts->ov_check_period = (HZ * maxsec) / 2;
507 dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
508 cpts->ov_check_period);
509
510 if (cpts->cc.mult || cpts->cc.shift)
511 return;
512
513 clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
514 freq, NSEC_PER_SEC, maxsec);
515
516 frac = 0;
517 ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
518
519 dev_info(cpts->dev,
520 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
521 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
522}
523
524static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
525{
526 int ret = -EINVAL;
527 u32 prop;
528
529 if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
530 cpts->cc.mult = prop;
531
532 if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
533 cpts->cc.shift = prop;
534
535 if ((cpts->cc.mult && !cpts->cc.shift) ||
536 (!cpts->cc.mult && cpts->cc.shift))
537 goto of_error;
538
539 return 0;
540
541of_error:
542 dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
543 return ret;
544}
545
546struct cpts *cpts_create(struct device *dev, void __iomem *regs,
547 struct device_node *node)
548{
549 struct cpts *cpts;
550 int ret;
551
552 cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
553 if (!cpts)
554 return ERR_PTR(-ENOMEM);
555
556 cpts->dev = dev;
557 cpts->reg = (struct cpsw_cpts __iomem *)regs;
558 spin_lock_init(&cpts->lock);
559
560 ret = cpts_of_parse(cpts, node);
561 if (ret)
562 return ERR_PTR(ret);
563
564 cpts->refclk = devm_clk_get(dev, "cpts");
565 if (IS_ERR(cpts->refclk)) {
566 dev_err(dev, "Failed to get cpts refclk\n");
567 return ERR_PTR(PTR_ERR(cpts->refclk));
568 }
569
570 clk_prepare(cpts->refclk);
571
572 cpts->cc.read = cpts_systim_read;
573 cpts->cc.mask = CLOCKSOURCE_MASK(32);
574 cpts->info = cpts_info;
575
576 cpts_calc_mult_shift(cpts);
577
578
579
580 cpts->cc_mult = cpts->cc.mult;
581
582 return cpts;
583}
584EXPORT_SYMBOL_GPL(cpts_create);
585
586void cpts_release(struct cpts *cpts)
587{
588 if (!cpts)
589 return;
590
591 if (WARN_ON(!cpts->refclk))
592 return;
593
594 clk_unprepare(cpts->refclk);
595}
596EXPORT_SYMBOL_GPL(cpts_release);
597
598MODULE_LICENSE("GPL v2");
599MODULE_DESCRIPTION("TI CPTS driver");
600MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
601
