1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * PTP 1588 clock support |
4 | * |
5 | * Copyright (C) 2010 OMICRON electronics GmbH |
6 | */ |
7 | #include <linux/device.h> |
8 | #include <linux/err.h> |
9 | #include <linux/init.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/module.h> |
12 | #include <linux/posix-clock.h> |
13 | #include <linux/pps_kernel.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/syscalls.h> |
16 | #include <linux/uaccess.h> |
17 | #include <linux/debugfs.h> |
18 | #include <linux/xarray.h> |
19 | #include <uapi/linux/sched/types.h> |
20 | |
21 | #include "ptp_private.h" |
22 | |
23 | #define PTP_MAX_ALARMS 4 |
24 | #define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT) |
25 | #define PTP_PPS_EVENT PPS_CAPTUREASSERT |
26 | #define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC) |
27 | |
28 | const struct class ptp_class = { |
29 | .name = "ptp" , |
30 | .dev_groups = ptp_groups |
31 | }; |
32 | |
33 | /* private globals */ |
34 | |
35 | static dev_t ptp_devt; |
36 | |
37 | static DEFINE_XARRAY_ALLOC(ptp_clocks_map); |
38 | |
39 | /* time stamp event queue operations */ |
40 | |
41 | static inline int queue_free(struct timestamp_event_queue *q) |
42 | { |
43 | return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1; |
44 | } |
45 | |
46 | static void enqueue_external_timestamp(struct timestamp_event_queue *queue, |
47 | struct ptp_clock_event *src) |
48 | { |
49 | struct ptp_extts_event *dst; |
50 | struct timespec64 offset_ts; |
51 | unsigned long flags; |
52 | s64 seconds; |
53 | u32 remainder; |
54 | |
55 | if (src->type == PTP_CLOCK_EXTTS) { |
56 | seconds = div_u64_rem(dividend: src->timestamp, divisor: 1000000000, remainder: &remainder); |
57 | } else if (src->type == PTP_CLOCK_EXTOFF) { |
58 | offset_ts = ns_to_timespec64(nsec: src->offset); |
59 | seconds = offset_ts.tv_sec; |
60 | remainder = offset_ts.tv_nsec; |
61 | } else { |
62 | WARN(1, "%s: unknown type %d\n" , __func__, src->type); |
63 | return; |
64 | } |
65 | |
66 | spin_lock_irqsave(&queue->lock, flags); |
67 | |
68 | dst = &queue->buf[queue->tail]; |
69 | dst->index = src->index; |
70 | dst->flags = PTP_EXTTS_EVENT_VALID; |
71 | dst->t.sec = seconds; |
72 | dst->t.nsec = remainder; |
73 | if (src->type == PTP_CLOCK_EXTOFF) |
74 | dst->flags |= PTP_EXT_OFFSET; |
75 | |
76 | /* Both WRITE_ONCE() are paired with READ_ONCE() in queue_cnt() */ |
77 | if (!queue_free(q: queue)) |
78 | WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS); |
79 | |
80 | WRITE_ONCE(queue->tail, (queue->tail + 1) % PTP_MAX_TIMESTAMPS); |
81 | |
82 | spin_unlock_irqrestore(lock: &queue->lock, flags); |
83 | } |
84 | |
85 | /* posix clock implementation */ |
86 | |
87 | static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp) |
88 | { |
89 | tp->tv_sec = 0; |
90 | tp->tv_nsec = 1; |
91 | return 0; |
92 | } |
93 | |
94 | static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp) |
95 | { |
96 | struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); |
97 | |
98 | if (ptp_clock_freerun(ptp)) { |
99 | pr_err("ptp: physical clock is free running\n" ); |
100 | return -EBUSY; |
101 | } |
102 | |
103 | return ptp->info->settime64(ptp->info, tp); |
104 | } |
105 | |
106 | static int ptp_clock_gettime(struct posix_clock *pc, struct timespec64 *tp) |
107 | { |
108 | struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); |
109 | int err; |
110 | |
111 | if (ptp->info->gettimex64) |
112 | err = ptp->info->gettimex64(ptp->info, tp, NULL); |
113 | else |
114 | err = ptp->info->gettime64(ptp->info, tp); |
115 | return err; |
116 | } |
117 | |
118 | static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx) |
119 | { |
120 | struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); |
121 | struct ptp_clock_info *ops; |
122 | int err = -EOPNOTSUPP; |
123 | |
124 | if (ptp_clock_freerun(ptp)) { |
125 | pr_err("ptp: physical clock is free running\n" ); |
126 | return -EBUSY; |
127 | } |
128 | |
129 | ops = ptp->info; |
130 | |
131 | if (tx->modes & ADJ_SETOFFSET) { |
132 | struct timespec64 ts; |
133 | ktime_t kt; |
134 | s64 delta; |
135 | |
136 | ts.tv_sec = tx->time.tv_sec; |
137 | ts.tv_nsec = tx->time.tv_usec; |
138 | |
139 | if (!(tx->modes & ADJ_NANO)) |
140 | ts.tv_nsec *= 1000; |
141 | |
142 | if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC) |
143 | return -EINVAL; |
144 | |
145 | kt = timespec64_to_ktime(ts); |
146 | delta = ktime_to_ns(kt); |
147 | err = ops->adjtime(ops, delta); |
148 | } else if (tx->modes & ADJ_FREQUENCY) { |
149 | long ppb = scaled_ppm_to_ppb(ppm: tx->freq); |
150 | if (ppb > ops->max_adj || ppb < -ops->max_adj) |
151 | return -ERANGE; |
152 | err = ops->adjfine(ops, tx->freq); |
153 | ptp->dialed_frequency = tx->freq; |
154 | } else if (tx->modes & ADJ_OFFSET) { |
155 | if (ops->adjphase) { |
156 | s32 max_phase_adj = ops->getmaxphase(ops); |
157 | s32 offset = tx->offset; |
158 | |
159 | if (!(tx->modes & ADJ_NANO)) |
160 | offset *= NSEC_PER_USEC; |
161 | |
162 | if (offset > max_phase_adj || offset < -max_phase_adj) |
163 | return -ERANGE; |
164 | |
165 | err = ops->adjphase(ops, offset); |
166 | } |
167 | } else if (tx->modes == 0) { |
168 | tx->freq = ptp->dialed_frequency; |
169 | err = 0; |
170 | } |
171 | |
172 | return err; |
173 | } |
174 | |
175 | static struct posix_clock_operations ptp_clock_ops = { |
176 | .owner = THIS_MODULE, |
177 | .clock_adjtime = ptp_clock_adjtime, |
178 | .clock_gettime = ptp_clock_gettime, |
179 | .clock_getres = ptp_clock_getres, |
180 | .clock_settime = ptp_clock_settime, |
181 | .ioctl = ptp_ioctl, |
182 | .open = ptp_open, |
183 | .release = ptp_release, |
184 | .poll = ptp_poll, |
185 | .read = ptp_read, |
186 | }; |
187 | |
188 | static void ptp_clock_release(struct device *dev) |
189 | { |
190 | struct ptp_clock *ptp = container_of(dev, struct ptp_clock, dev); |
191 | struct timestamp_event_queue *tsevq; |
192 | unsigned long flags; |
193 | |
194 | ptp_cleanup_pin_groups(ptp); |
195 | kfree(objp: ptp->vclock_index); |
196 | mutex_destroy(lock: &ptp->pincfg_mux); |
197 | mutex_destroy(lock: &ptp->n_vclocks_mux); |
198 | /* Delete first entry */ |
199 | spin_lock_irqsave(&ptp->tsevqs_lock, flags); |
200 | tsevq = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue, |
201 | qlist); |
202 | list_del(entry: &tsevq->qlist); |
203 | spin_unlock_irqrestore(lock: &ptp->tsevqs_lock, flags); |
204 | bitmap_free(bitmap: tsevq->mask); |
205 | kfree(objp: tsevq); |
206 | debugfs_remove(dentry: ptp->debugfs_root); |
207 | xa_erase(&ptp_clocks_map, index: ptp->index); |
208 | kfree(objp: ptp); |
209 | } |
210 | |
211 | static int ptp_getcycles64(struct ptp_clock_info *info, struct timespec64 *ts) |
212 | { |
213 | if (info->getcyclesx64) |
214 | return info->getcyclesx64(info, ts, NULL); |
215 | else |
216 | return info->gettime64(info, ts); |
217 | } |
218 | |
219 | static void ptp_aux_kworker(struct kthread_work *work) |
220 | { |
221 | struct ptp_clock *ptp = container_of(work, struct ptp_clock, |
222 | aux_work.work); |
223 | struct ptp_clock_info *info = ptp->info; |
224 | long delay; |
225 | |
226 | delay = info->do_aux_work(info); |
227 | |
228 | if (delay >= 0) |
229 | kthread_queue_delayed_work(worker: ptp->kworker, dwork: &ptp->aux_work, delay); |
230 | } |
231 | |
232 | /* public interface */ |
233 | |
234 | struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, |
235 | struct device *parent) |
236 | { |
237 | struct ptp_clock *ptp; |
238 | struct timestamp_event_queue *queue = NULL; |
239 | int err, index, major = MAJOR(ptp_devt); |
240 | char debugfsname[16]; |
241 | size_t size; |
242 | |
243 | if (info->n_alarm > PTP_MAX_ALARMS) |
244 | return ERR_PTR(error: -EINVAL); |
245 | |
246 | /* Initialize a clock structure. */ |
247 | ptp = kzalloc(size: sizeof(struct ptp_clock), GFP_KERNEL); |
248 | if (!ptp) { |
249 | err = -ENOMEM; |
250 | goto no_memory; |
251 | } |
252 | |
253 | err = xa_alloc(xa: &ptp_clocks_map, id: &index, entry: ptp, xa_limit_31b, |
254 | GFP_KERNEL); |
255 | if (err) |
256 | goto no_slot; |
257 | |
258 | ptp->clock.ops = ptp_clock_ops; |
259 | ptp->info = info; |
260 | ptp->devid = MKDEV(major, index); |
261 | ptp->index = index; |
262 | INIT_LIST_HEAD(list: &ptp->tsevqs); |
263 | queue = kzalloc(size: sizeof(*queue), GFP_KERNEL); |
264 | if (!queue) { |
265 | err = -ENOMEM; |
266 | goto no_memory_queue; |
267 | } |
268 | list_add_tail(new: &queue->qlist, head: &ptp->tsevqs); |
269 | spin_lock_init(&ptp->tsevqs_lock); |
270 | queue->mask = bitmap_alloc(PTP_MAX_CHANNELS, GFP_KERNEL); |
271 | if (!queue->mask) { |
272 | err = -ENOMEM; |
273 | goto no_memory_bitmap; |
274 | } |
275 | bitmap_set(map: queue->mask, start: 0, PTP_MAX_CHANNELS); |
276 | spin_lock_init(&queue->lock); |
277 | mutex_init(&ptp->pincfg_mux); |
278 | mutex_init(&ptp->n_vclocks_mux); |
279 | init_waitqueue_head(&ptp->tsev_wq); |
280 | |
281 | if (ptp->info->getcycles64 || ptp->info->getcyclesx64) { |
282 | ptp->has_cycles = true; |
283 | if (!ptp->info->getcycles64 && ptp->info->getcyclesx64) |
284 | ptp->info->getcycles64 = ptp_getcycles64; |
285 | } else { |
286 | /* Free running cycle counter not supported, use time. */ |
287 | ptp->info->getcycles64 = ptp_getcycles64; |
288 | |
289 | if (ptp->info->gettimex64) |
290 | ptp->info->getcyclesx64 = ptp->info->gettimex64; |
291 | |
292 | if (ptp->info->getcrosststamp) |
293 | ptp->info->getcrosscycles = ptp->info->getcrosststamp; |
294 | } |
295 | |
296 | if (ptp->info->do_aux_work) { |
297 | kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker); |
298 | ptp->kworker = kthread_create_worker(flags: 0, namefmt: "ptp%d" , ptp->index); |
299 | if (IS_ERR(ptr: ptp->kworker)) { |
300 | err = PTR_ERR(ptr: ptp->kworker); |
301 | pr_err("failed to create ptp aux_worker %d\n" , err); |
302 | goto kworker_err; |
303 | } |
304 | } |
305 | |
306 | /* PTP virtual clock is being registered under physical clock */ |
307 | if (parent && parent->class && parent->class->name && |
308 | strcmp(parent->class->name, "ptp" ) == 0) |
309 | ptp->is_virtual_clock = true; |
310 | |
311 | if (!ptp->is_virtual_clock) { |
312 | ptp->max_vclocks = PTP_DEFAULT_MAX_VCLOCKS; |
313 | |
314 | size = sizeof(int) * ptp->max_vclocks; |
315 | ptp->vclock_index = kzalloc(size, GFP_KERNEL); |
316 | if (!ptp->vclock_index) { |
317 | err = -ENOMEM; |
318 | goto no_mem_for_vclocks; |
319 | } |
320 | } |
321 | |
322 | err = ptp_populate_pin_groups(ptp); |
323 | if (err) |
324 | goto no_pin_groups; |
325 | |
326 | /* Register a new PPS source. */ |
327 | if (info->pps) { |
328 | struct pps_source_info pps; |
329 | memset(&pps, 0, sizeof(pps)); |
330 | snprintf(buf: pps.name, PPS_MAX_NAME_LEN, fmt: "ptp%d" , index); |
331 | pps.mode = PTP_PPS_MODE; |
332 | pps.owner = info->owner; |
333 | ptp->pps_source = pps_register_source(info: &pps, PTP_PPS_DEFAULTS); |
334 | if (IS_ERR(ptr: ptp->pps_source)) { |
335 | err = PTR_ERR(ptr: ptp->pps_source); |
336 | pr_err("failed to register pps source\n" ); |
337 | goto no_pps; |
338 | } |
339 | ptp->pps_source->lookup_cookie = ptp; |
340 | } |
341 | |
342 | /* Initialize a new device of our class in our clock structure. */ |
343 | device_initialize(dev: &ptp->dev); |
344 | ptp->dev.devt = ptp->devid; |
345 | ptp->dev.class = &ptp_class; |
346 | ptp->dev.parent = parent; |
347 | ptp->dev.groups = ptp->pin_attr_groups; |
348 | ptp->dev.release = ptp_clock_release; |
349 | dev_set_drvdata(dev: &ptp->dev, data: ptp); |
350 | dev_set_name(dev: &ptp->dev, name: "ptp%d" , ptp->index); |
351 | |
352 | /* Create a posix clock and link it to the device. */ |
353 | err = posix_clock_register(clk: &ptp->clock, dev: &ptp->dev); |
354 | if (err) { |
355 | if (ptp->pps_source) |
356 | pps_unregister_source(pps: ptp->pps_source); |
357 | |
358 | if (ptp->kworker) |
359 | kthread_destroy_worker(worker: ptp->kworker); |
360 | |
361 | put_device(dev: &ptp->dev); |
362 | |
363 | pr_err("failed to create posix clock\n" ); |
364 | return ERR_PTR(error: err); |
365 | } |
366 | |
367 | /* Debugfs initialization */ |
368 | snprintf(buf: debugfsname, size: sizeof(debugfsname), fmt: "ptp%d" , ptp->index); |
369 | ptp->debugfs_root = debugfs_create_dir(name: debugfsname, NULL); |
370 | |
371 | return ptp; |
372 | |
373 | no_pps: |
374 | ptp_cleanup_pin_groups(ptp); |
375 | no_pin_groups: |
376 | kfree(objp: ptp->vclock_index); |
377 | no_mem_for_vclocks: |
378 | if (ptp->kworker) |
379 | kthread_destroy_worker(worker: ptp->kworker); |
380 | kworker_err: |
381 | mutex_destroy(lock: &ptp->pincfg_mux); |
382 | mutex_destroy(lock: &ptp->n_vclocks_mux); |
383 | bitmap_free(bitmap: queue->mask); |
384 | no_memory_bitmap: |
385 | list_del(entry: &queue->qlist); |
386 | kfree(objp: queue); |
387 | no_memory_queue: |
388 | xa_erase(&ptp_clocks_map, index); |
389 | no_slot: |
390 | kfree(objp: ptp); |
391 | no_memory: |
392 | return ERR_PTR(error: err); |
393 | } |
394 | EXPORT_SYMBOL(ptp_clock_register); |
395 | |
396 | static int unregister_vclock(struct device *dev, void *data) |
397 | { |
398 | struct ptp_clock *ptp = dev_get_drvdata(dev); |
399 | |
400 | ptp_vclock_unregister(info_to_vclock(ptp->info)); |
401 | return 0; |
402 | } |
403 | |
404 | int ptp_clock_unregister(struct ptp_clock *ptp) |
405 | { |
406 | if (ptp_vclock_in_use(ptp)) { |
407 | device_for_each_child(dev: &ptp->dev, NULL, fn: unregister_vclock); |
408 | } |
409 | |
410 | ptp->defunct = 1; |
411 | wake_up_interruptible(&ptp->tsev_wq); |
412 | |
413 | if (ptp->kworker) { |
414 | kthread_cancel_delayed_work_sync(work: &ptp->aux_work); |
415 | kthread_destroy_worker(worker: ptp->kworker); |
416 | } |
417 | |
418 | /* Release the clock's resources. */ |
419 | if (ptp->pps_source) |
420 | pps_unregister_source(pps: ptp->pps_source); |
421 | |
422 | posix_clock_unregister(clk: &ptp->clock); |
423 | |
424 | return 0; |
425 | } |
426 | EXPORT_SYMBOL(ptp_clock_unregister); |
427 | |
428 | void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event) |
429 | { |
430 | struct timestamp_event_queue *tsevq; |
431 | struct pps_event_time evt; |
432 | unsigned long flags; |
433 | |
434 | switch (event->type) { |
435 | |
436 | case PTP_CLOCK_ALARM: |
437 | break; |
438 | |
439 | case PTP_CLOCK_EXTTS: |
440 | case PTP_CLOCK_EXTOFF: |
441 | /* Enqueue timestamp on selected queues */ |
442 | spin_lock_irqsave(&ptp->tsevqs_lock, flags); |
443 | list_for_each_entry(tsevq, &ptp->tsevqs, qlist) { |
444 | if (test_bit((unsigned int)event->index, tsevq->mask)) |
445 | enqueue_external_timestamp(queue: tsevq, src: event); |
446 | } |
447 | spin_unlock_irqrestore(lock: &ptp->tsevqs_lock, flags); |
448 | wake_up_interruptible(&ptp->tsev_wq); |
449 | break; |
450 | |
451 | case PTP_CLOCK_PPS: |
452 | pps_get_ts(ts: &evt); |
453 | pps_event(pps: ptp->pps_source, ts: &evt, PTP_PPS_EVENT, NULL); |
454 | break; |
455 | |
456 | case PTP_CLOCK_PPSUSR: |
457 | pps_event(pps: ptp->pps_source, ts: &event->pps_times, |
458 | PTP_PPS_EVENT, NULL); |
459 | break; |
460 | } |
461 | } |
462 | EXPORT_SYMBOL(ptp_clock_event); |
463 | |
464 | int ptp_clock_index(struct ptp_clock *ptp) |
465 | { |
466 | return ptp->index; |
467 | } |
468 | EXPORT_SYMBOL(ptp_clock_index); |
469 | |
470 | int ptp_find_pin(struct ptp_clock *ptp, |
471 | enum ptp_pin_function func, unsigned int chan) |
472 | { |
473 | struct ptp_pin_desc *pin = NULL; |
474 | int i; |
475 | |
476 | for (i = 0; i < ptp->info->n_pins; i++) { |
477 | if (ptp->info->pin_config[i].func == func && |
478 | ptp->info->pin_config[i].chan == chan) { |
479 | pin = &ptp->info->pin_config[i]; |
480 | break; |
481 | } |
482 | } |
483 | |
484 | return pin ? i : -1; |
485 | } |
486 | EXPORT_SYMBOL(ptp_find_pin); |
487 | |
488 | int ptp_find_pin_unlocked(struct ptp_clock *ptp, |
489 | enum ptp_pin_function func, unsigned int chan) |
490 | { |
491 | int result; |
492 | |
493 | mutex_lock(&ptp->pincfg_mux); |
494 | |
495 | result = ptp_find_pin(ptp, func, chan); |
496 | |
497 | mutex_unlock(lock: &ptp->pincfg_mux); |
498 | |
499 | return result; |
500 | } |
501 | EXPORT_SYMBOL(ptp_find_pin_unlocked); |
502 | |
503 | int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay) |
504 | { |
505 | return kthread_mod_delayed_work(worker: ptp->kworker, dwork: &ptp->aux_work, delay); |
506 | } |
507 | EXPORT_SYMBOL(ptp_schedule_worker); |
508 | |
509 | void ptp_cancel_worker_sync(struct ptp_clock *ptp) |
510 | { |
511 | kthread_cancel_delayed_work_sync(work: &ptp->aux_work); |
512 | } |
513 | EXPORT_SYMBOL(ptp_cancel_worker_sync); |
514 | |
515 | /* module operations */ |
516 | |
517 | static void __exit ptp_exit(void) |
518 | { |
519 | class_unregister(class: &ptp_class); |
520 | unregister_chrdev_region(ptp_devt, MINORMASK + 1); |
521 | xa_destroy(&ptp_clocks_map); |
522 | } |
523 | |
524 | static int __init ptp_init(void) |
525 | { |
526 | int err; |
527 | |
528 | err = class_register(class: &ptp_class); |
529 | if (err) { |
530 | pr_err("ptp: failed to allocate class\n" ); |
531 | return err; |
532 | } |
533 | |
534 | err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp" ); |
535 | if (err < 0) { |
536 | pr_err("ptp: failed to allocate device region\n" ); |
537 | goto no_region; |
538 | } |
539 | |
540 | pr_info("PTP clock support registered\n" ); |
541 | return 0; |
542 | |
543 | no_region: |
544 | class_unregister(class: &ptp_class); |
545 | return err; |
546 | } |
547 | |
548 | subsys_initcall(ptp_init); |
549 | module_exit(ptp_exit); |
550 | |
551 | MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>" ); |
552 | MODULE_DESCRIPTION("PTP clocks support" ); |
553 | MODULE_LICENSE("GPL" ); |
554 | |