drivers/net/ethernet/ti/cpts.c

   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
  35 static int cpts_event_port(struct cpts_event *event)
  36 {
  37         return (event->high >> PORT_NUMBER_SHIFT) & PORT_NUMBER_MASK;
  38 }
  39
  40 static int event_expired(struct cpts_event *event)
  41 {
  42         return time_after(jiffies, event->tmo);
  43 }
  44
  45 static int event_type(struct cpts_event *event)
  46 {
  47         return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
  48 }
  49
  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
  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
  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  */
 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
 178 void cpts_misc_interrupt(struct cpts *cpts)
 179 {
 180         cpts_fifo_read(cpts, -1);
 181 }
 182 EXPORT_SYMBOL_GPL(cpts_misc_interrupt);
 183
 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
 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
 216 static 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
 230 static 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
 241 static 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
 260 static 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
 275 static 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
 299 static 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
 314 static 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
 365 static 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
 392 static 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
 419 static 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
 434 static 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
 457 static 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
 493 void 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 }
 521 EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 522
 523 void 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 }
 547 EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 548
 549 int 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
 579 err_ptp:
 580         clk_disable(cpts->refclk);
 581         return err;
 582 }
 583 EXPORT_SYMBOL_GPL(cpts_register);
 584
 585 void 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 }
 602 EXPORT_SYMBOL_GPL(cpts_unregister);
 603
 604 static 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
 641 static void cpts_clk_unregister(void *clk)
 642 {
 643         clk_hw_unregister_mux(clk);
 644 }
 645
 646 static void cpts_clk_del_provider(void *np)
 647 {
 648         of_clk_del_provider(np);
 649 }
 650
 651 static 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
 719 mux_fail:
 720         of_node_put(refclk_np);
 721         return ret;
 722 }
 723
 724 static 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
 741 of_error:
 742         dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
 743         return ret;
 744 }
 745
 746 struct 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 }
 798 EXPORT_SYMBOL_GPL(cpts_create);
 799
 800 void 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 }
 810 EXPORT_SYMBOL_GPL(cpts_release);
 811
 812 MODULE_LICENSE("GPL v2");
 813 MODULE_DESCRIPTION("TI CPTS driver");
 814 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");