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>
29 #include <linux/if_ether.h>
30 #include <linux/if_vlan.h>
36 #define cpts_read32(c, r) __raw_readl(&c->reg->r)
37 #define cpts_write32(c, v, r) __raw_writel(v, &c->reg->r)
39 static int event_expired(struct cpts_event *event)
41 return time_after(jiffies, event->tmo);
44 static int event_type(struct cpts_event *event)
46 return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
49 static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
51 u32 r = cpts_read32(cpts, intstat_raw);
53 if (r & TS_PEND_RAW) {
54 *high = cpts_read32(cpts, event_high);
55 *low = cpts_read32(cpts, event_low);
56 cpts_write32(cpts, EVENT_POP, event_pop);
63 * Returns zero if matching event type was found.
65 static int cpts_fifo_read(struct cpts *cpts, int match)
69 struct cpts_event *event;
71 for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
72 if (cpts_fifo_pop(cpts, &hi, &lo))
74 if (list_empty(&cpts->pool)) {
75 pr_err("cpts: event pool is empty\n");
78 event = list_first_entry(&cpts->pool, struct cpts_event, list);
79 event->tmo = jiffies + 2;
82 type = event_type(event);
87 list_del_init(&event->list);
88 list_add_tail(&event->list, &cpts->events);
95 pr_err("cpts: unknown event type\n");
101 return type == match ? 0 : -1;
104 static cycle_t cpts_systim_read(const struct cyclecounter *cc)
107 struct cpts_event *event;
108 struct list_head *this, *next;
109 struct cpts *cpts = container_of(cc, struct cpts, cc);
111 cpts_write32(cpts, TS_PUSH, ts_push);
112 if (cpts_fifo_read(cpts, CPTS_EV_PUSH))
113 pr_err("cpts: unable to obtain a time stamp\n");
115 list_for_each_safe(this, next, &cpts->events) {
116 event = list_entry(this, struct cpts_event, list);
117 if (event_type(event) == CPTS_EV_PUSH) {
118 list_del_init(&event->list);
119 list_add(&event->list, &cpts->pool);
128 /* PTP clock operations */
130 static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
136 struct cpts *cpts = container_of(ptp, struct cpts, info);
142 mult = cpts->cc_mult;
145 diff = div_u64(adj, 1000000000ULL);
147 spin_lock_irqsave(&cpts->lock, flags);
149 timecounter_read(&cpts->tc);
151 cpts->cc.mult = neg_adj ? mult - diff : mult + diff;
153 spin_unlock_irqrestore(&cpts->lock, flags);
158 static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
161 struct cpts *cpts = container_of(ptp, struct cpts, info);
163 spin_lock_irqsave(&cpts->lock, flags);
164 timecounter_adjtime(&cpts->tc, delta);
165 spin_unlock_irqrestore(&cpts->lock, flags);
170 static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
174 struct cpts *cpts = container_of(ptp, struct cpts, info);
176 spin_lock_irqsave(&cpts->lock, flags);
177 ns = timecounter_read(&cpts->tc);
178 spin_unlock_irqrestore(&cpts->lock, flags);
180 *ts = ns_to_timespec64(ns);
185 static int cpts_ptp_settime(struct ptp_clock_info *ptp,
186 const struct timespec64 *ts)
190 struct cpts *cpts = container_of(ptp, struct cpts, info);
192 ns = timespec64_to_ns(ts);
194 spin_lock_irqsave(&cpts->lock, flags);
195 timecounter_init(&cpts->tc, &cpts->cc, ns);
196 spin_unlock_irqrestore(&cpts->lock, flags);
201 static int cpts_ptp_enable(struct ptp_clock_info *ptp,
202 struct ptp_clock_request *rq, int on)
207 static struct ptp_clock_info cpts_info = {
208 .owner = THIS_MODULE,
209 .name = "CTPS timer",
214 .adjfreq = cpts_ptp_adjfreq,
215 .adjtime = cpts_ptp_adjtime,
216 .gettime64 = cpts_ptp_gettime,
217 .settime64 = cpts_ptp_settime,
218 .enable = cpts_ptp_enable,
221 static void cpts_overflow_check(struct work_struct *work)
223 struct timespec64 ts;
224 struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
226 cpts_write32(cpts, CPTS_EN, control);
227 cpts_write32(cpts, TS_PEND_EN, int_enable);
228 cpts_ptp_gettime(&cpts->info, &ts);
229 pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
230 schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
233 static void cpts_clk_init(struct device *dev, struct cpts *cpts)
235 cpts->refclk = devm_clk_get(dev, "cpts");
236 if (IS_ERR(cpts->refclk)) {
237 dev_err(dev, "Failed to get cpts refclk\n");
241 clk_prepare_enable(cpts->refclk);
244 static void cpts_clk_release(struct cpts *cpts)
246 clk_disable(cpts->refclk);
249 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
250 u16 ts_seqid, u8 ts_msgtype)
253 unsigned int offset = 0;
254 u8 *msgtype, *data = skb->data;
256 if (ptp_class & PTP_CLASS_VLAN)
259 switch (ptp_class & PTP_CLASS_PMASK) {
261 offset += ETH_HLEN + IPV4_HLEN(data + offset) + UDP_HLEN;
264 offset += ETH_HLEN + IP6_HLEN + UDP_HLEN;
273 if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid))
276 if (unlikely(ptp_class & PTP_CLASS_V1))
277 msgtype = data + offset + OFF_PTP_CONTROL;
279 msgtype = data + offset;
281 seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
283 return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid));
286 static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
289 struct cpts_event *event;
290 struct list_head *this, *next;
291 unsigned int class = ptp_classify_raw(skb);
296 if (class == PTP_CLASS_NONE)
299 spin_lock_irqsave(&cpts->lock, flags);
300 cpts_fifo_read(cpts, CPTS_EV_PUSH);
301 list_for_each_safe(this, next, &cpts->events) {
302 event = list_entry(this, struct cpts_event, list);
303 if (event_expired(event)) {
304 list_del_init(&event->list);
305 list_add(&event->list, &cpts->pool);
308 mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK;
309 seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK;
310 if (ev_type == event_type(event) &&
311 cpts_match(skb, class, seqid, mtype)) {
312 ns = timecounter_cyc2time(&cpts->tc, event->low);
313 list_del_init(&event->list);
314 list_add(&event->list, &cpts->pool);
318 spin_unlock_irqrestore(&cpts->lock, flags);
323 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
326 struct skb_shared_hwtstamps *ssh;
328 if (!cpts->rx_enable)
330 ns = cpts_find_ts(cpts, skb, CPTS_EV_RX);
333 ssh = skb_hwtstamps(skb);
334 memset(ssh, 0, sizeof(*ssh));
335 ssh->hwtstamp = ns_to_ktime(ns);
338 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
341 struct skb_shared_hwtstamps ssh;
343 if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
345 ns = cpts_find_ts(cpts, skb, CPTS_EV_TX);
348 memset(&ssh, 0, sizeof(ssh));
349 ssh.hwtstamp = ns_to_ktime(ns);
350 skb_tstamp_tx(skb, &ssh);
353 #endif /*CONFIG_TI_CPTS*/
355 int cpts_register(struct device *dev, struct cpts *cpts,
358 #ifdef CONFIG_TI_CPTS
362 cpts->info = cpts_info;
363 cpts->clock = ptp_clock_register(&cpts->info, dev);
364 if (IS_ERR(cpts->clock)) {
365 err = PTR_ERR(cpts->clock);
369 spin_lock_init(&cpts->lock);
371 cpts->cc.read = cpts_systim_read;
372 cpts->cc.mask = CLOCKSOURCE_MASK(32);
373 cpts->cc_mult = mult;
374 cpts->cc.mult = mult;
375 cpts->cc.shift = shift;
377 INIT_LIST_HEAD(&cpts->events);
378 INIT_LIST_HEAD(&cpts->pool);
379 for (i = 0; i < CPTS_MAX_EVENTS; i++)
380 list_add(&cpts->pool_data[i].list, &cpts->pool);
382 cpts_clk_init(dev, cpts);
383 cpts_write32(cpts, CPTS_EN, control);
384 cpts_write32(cpts, TS_PEND_EN, int_enable);
386 spin_lock_irqsave(&cpts->lock, flags);
387 timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
388 spin_unlock_irqrestore(&cpts->lock, flags);
390 INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
391 schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
393 cpts->phc_index = ptp_clock_index(cpts->clock);
398 void cpts_unregister(struct cpts *cpts)
400 #ifdef CONFIG_TI_CPTS
402 ptp_clock_unregister(cpts->clock);
403 cancel_delayed_work_sync(&cpts->overflow_work);
406 cpts_clk_release(cpts);