2 * TI Common Platform Time Sync
4 * Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
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.
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.
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
20 #include <linux/err.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>
34 #define cpts_read32(c, r) __raw_readl(&c->reg->r)
35 #define cpts_write32(c, v, r) __raw_writel(v, &c->reg->r)
37 static int event_expired(struct cpts_event *event)
39 return time_after(jiffies, event->tmo);
42 static int event_type(struct cpts_event *event)
44 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
47 static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
49 u32 r = cpts_read32(cpts, intstat_raw);
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);
61 * Returns zero if matching event type was found.
63 static int cpts_fifo_read(struct cpts *cpts, int match)
67 struct cpts_event *event;
69 for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
70 if (cpts_fifo_pop(cpts, &hi, &lo))
72 if (list_empty(&cpts->pool)) {
73 pr_err("cpts: event pool is empty\n");
76 event = list_first_entry(&cpts->pool, struct cpts_event, list);
77 event->tmo = jiffies + 2;
80 type = event_type(event);
85 list_del_init(&event->list);
86 list_add_tail(&event->list, &cpts->events);
93 pr_err("cpts: unknown event type\n");
99 return type == match ? 0 : -1;
102 static cycle_t cpts_systim_read(const struct cyclecounter *cc)
105 struct cpts_event *event;
106 struct list_head *this, *next;
107 struct cpts *cpts = container_of(cc, struct cpts, cc);
109 cpts_write32(cpts, TS_PUSH, ts_push);
110 if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
111 pr_err("cpts: unable to obtain a time stamp\n");
113 list_for_each_safe(this, next, &cpts->events) {
114 event = list_entry(this, struct cpts_event, list);
115 if (event_type(event) == CPTS_EV_PUSH) {
116 list_del_init(&event->list);
117 list_add(&event->list, &cpts->pool);
126 /* PTP clock operations */
128 static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
134 struct cpts *cpts = container_of(ptp, struct cpts, info);
140 mult = cpts->cc_mult;
143 diff = div_u64(adj, 1000000000ULL);
145 spin_lock_irqsave(&cpts->lock, flags);
147 timecounter_read(&cpts->tc);
149 cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
151 spin_unlock_irqrestore(&cpts->lock, flags);
156 static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
160 struct cpts *cpts = container_of(ptp, struct cpts, info);
162 spin_lock_irqsave(&cpts->lock, flags);
163 now = timecounter_read(&cpts->tc);
165 timecounter_init(&cpts->tc, &cpts->cc, now);
166 spin_unlock_irqrestore(&cpts->lock, flags);
171 static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
176 struct cpts *cpts = container_of(ptp, struct cpts, info);
178 spin_lock_irqsave(&cpts->lock, flags);
179 ns = timecounter_read(&cpts->tc);
180 spin_unlock_irqrestore(&cpts->lock, flags);
182 ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
183 ts->tv_nsec = remainder;
188 static int cpts_ptp_settime(struct ptp_clock_info *ptp,
189 const struct timespec *ts)
193 struct cpts *cpts = container_of(ptp, struct cpts, info);
195 ns = ts->tv_sec * 1000000000ULL;
198 spin_lock_irqsave(&cpts->lock, flags);
199 timecounter_init(&cpts->tc, &cpts->cc, ns);
200 spin_unlock_irqrestore(&cpts->lock, flags);
205 static int cpts_ptp_enable(struct ptp_clock_info *ptp,
206 struct ptp_clock_request *rq, int on)
211 static struct ptp_clock_info cpts_info = {
212 .owner = THIS_MODULE,
213 .name = "CTPS timer",
218 .adjfreq = cpts_ptp_adjfreq,
219 .adjtime = cpts_ptp_adjtime,
220 .gettime = cpts_ptp_gettime,
221 .settime = cpts_ptp_settime,
222 .enable = cpts_ptp_enable,
225 static void cpts_overflow_check(struct work_struct *work)
228 struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
230 cpts_write32(cpts, CPTS_EN, control);
231 cpts_write32(cpts, TS_PEND_EN, int_enable);
232 cpts_ptp_gettime(&cpts->info, &ts);
233 pr_debug("cpts overflow check at %ld.%09lu\n", ts.tv_sec, ts.tv_nsec);
234 schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
237 #define CPTS_REF_CLOCK_NAME "cpsw_cpts_rft_clk"
239 static void cpts_clk_init(struct cpts *cpts)
241 cpts->refclk = clk_get(NULL, CPTS_REF_CLOCK_NAME);
242 if (IS_ERR(cpts->refclk)) {
243 pr_err("Failed to clk_get %s\n", CPTS_REF_CLOCK_NAME);
247 clk_prepare_enable(cpts->refclk);
250 static void cpts_clk_release(struct cpts *cpts)
252 clk_disable(cpts->refclk);
253 clk_put(cpts->refclk);
256 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
257 u16 ts_seqid, u8 ts_msgtype)
261 u8 *msgtype, *data = skb->data;
264 case PTP_CLASS_V1_IPV4:
265 case PTP_CLASS_V2_IPV4:
266 offset = ETH_HLEN + IPV4_HLEN(data) + UDP_HLEN;
268 case PTP_CLASS_V1_IPV6:
269 case PTP_CLASS_V2_IPV6:
272 case PTP_CLASS_V2_L2:
275 case PTP_CLASS_V2_VLAN:
276 offset = ETH_HLEN + VLAN_HLEN;
282 if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid))
285 if (unlikely(ptp_class & PTP_CLASS_V1))
286 msgtype = data + offset + OFF_PTP_CONTROL;
288 msgtype = data + offset;
290 seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
292 return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
295 static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
298 struct cpts_event *event;
299 struct list_head *this, *next;
300 unsigned int class = ptp_classify_raw(skb);
305 if (class == PTP_CLASS_NONE)
308 spin_lock_irqsave(&cpts->lock, flags);
309 cpts_fifo_read(cpts, CPTS_EV_PUSH);
310 list_for_each_safe(this, next, &cpts->events) {
311 event = list_entry(this, struct cpts_event, list);
312 if (event_expired(event)) {
313 list_del_init(&event->list);
314 list_add(&event->list, &cpts->pool);
317 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
318 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
319 if (ev_type == event_type(event) &&
320 cpts_match(skb, class, seqid, mtype)) {
321 ns = timecounter_cyc2time(&cpts->tc, event->low);
322 list_del_init(&event->list);
323 list_add(&event->list, &cpts->pool);
327 spin_unlock_irqrestore(&cpts->lock, flags);
332 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
335 struct skb_shared_hwtstamps *ssh;
337 if (!cpts->rx_enable)
339 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
342 ssh = skb_hwtstamps(skb);
343 memset(ssh, 0, sizeof(*ssh));
344 ssh->hwtstamp = ns_to_ktime(ns);
347 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
350 struct skb_shared_hwtstamps ssh;
352 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
354 ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
357 memset(&ssh, 0, sizeof(ssh));
358 ssh.hwtstamp = ns_to_ktime(ns);
359 skb_tstamp_tx(skb, &ssh);
362 #endif /*CONFIG_TI_CPTS*/
364 int cpts_register(struct device *dev, struct cpts *cpts,
367 #ifdef CONFIG_TI_CPTS
371 cpts->info = cpts_info;
372 cpts->clock = ptp_clock_register(&cpts->info, dev);
373 if (IS_ERR(cpts->clock)) {
374 err = PTR_ERR(cpts->clock);
378 spin_lock_init(&cpts->lock);
380 cpts->cc.read = cpts_systim_read;
381 cpts->cc.mask = CLOCKSOURCE_MASK(32);
382 cpts->cc_mult = mult;
383 cpts->cc.mult = mult;
384 cpts->cc.shift = shift;
386 INIT_LIST_HEAD(&cpts->events);
387 INIT_LIST_HEAD(&cpts->pool);
388 for (i = 0; i < CPTS_MAX_EVENTS; i++)
389 list_add(&cpts->pool_data[i].list, &cpts->pool);
392 cpts_write32(cpts, CPTS_EN, control);
393 cpts_write32(cpts, TS_PEND_EN, int_enable);
395 spin_lock_irqsave(&cpts->lock, flags);
396 timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
397 spin_unlock_irqrestore(&cpts->lock, flags);
399 INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
400 schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
402 cpts->phc_index = ptp_clock_index(cpts->clock);
407 void cpts_unregister(struct cpts *cpts)
409 #ifdef CONFIG_TI_CPTS
411 ptp_clock_unregister(cpts->clock);
412 cancel_delayed_work_sync(&cpts->overflow_work);
415 cpts_clk_release(cpts);