- Add Pulse-Per-Second timestamping using raw ffcounter and corresponding

  ffclock time in seconds.

- Add IOCTL to retrieve ffclock timestamps from userland.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)

1 files changed, 65 insertions, 0 deletions

diff --git a/sys/kern/kern_tc.c b/sys/kern/kern_tc.c
index 66e26d0..e5db8d9 100644
--- a/sys/kern/kern_tc.c
+++ b/sys/kern/kern_tc.c
@@ -1365,6 +1365,9 @@ pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
 {
 	pps_params_t *app;
 	struct pps_fetch_args *fapi;
+#ifdef FFCLOCK
+	struct pps_fetch_ffc_args *fapi_ffc;
+#endif
 #ifdef PPS_SYNC
 	struct pps_kcbind_args *kapi;
 #endif
@@ -1379,6 +1382,11 @@ pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
 		app = (pps_params_t *)data;
 		if (app->mode & ~pps->ppscap)
 			return (EINVAL);
+#ifdef FFCLOCK
+		/* Ensure only a single clock is selected for ffc timestamp. */
+		if ((app->mode & PPS_TSCLK_MASK) == PPS_TSCLK_MASK)
+			return (EINVAL);
+#endif
 		pps->ppsparam = *app;
 		return (0);
 	case PPS_IOC_GETPARAMS:
@@ -1398,6 +1406,31 @@ pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
 		pps->ppsinfo.current_mode = pps->ppsparam.mode;
 		fapi->pps_info_buf = pps->ppsinfo;
 		return (0);
+#ifdef FFCLOCK
+	case PPS_IOC_FETCH_FFCOUNTER:
+		fapi_ffc = (struct pps_fetch_ffc_args *)data;
+		if (fapi_ffc->tsformat && fapi_ffc->tsformat !=
+		    PPS_TSFMT_TSPEC)
+			return (EINVAL);
+		if (fapi_ffc->timeout.tv_sec || fapi_ffc->timeout.tv_nsec)
+			return (EOPNOTSUPP);
+		pps->ppsinfo_ffc.current_mode = pps->ppsparam.mode;
+		fapi_ffc->pps_info_buf_ffc = pps->ppsinfo_ffc;
+		/* Overwrite timestamps if feedback clock selected. */
+		switch (pps->ppsparam.mode & PPS_TSCLK_MASK) {
+		case PPS_TSCLK_FBCK:
+			fapi_ffc->pps_info_buf_ffc.assert_timestamp =
+			    pps->ppsinfo.assert_timestamp;
+			fapi_ffc->pps_info_buf_ffc.clear_timestamp =
+			    pps->ppsinfo.clear_timestamp;
+			break;
+		case PPS_TSCLK_FFWD:
+			break;
+		default:
+			break;
+		}
+		return (0);
+#endif /* FFCLOCK */
 	case PPS_IOC_KCBIND:
 #ifdef PPS_SYNC
 		kapi = (struct pps_kcbind_args *)data;
@@ -1426,6 +1459,9 @@ pps_init(struct pps_state *pps)
 		pps->ppscap |= PPS_OFFSETASSERT;
 	if (pps->ppscap & PPS_CAPTURECLEAR)
 		pps->ppscap |= PPS_OFFSETCLEAR;
+#ifdef FFCLOCK
+	pps->ppscap |= PPS_TSCLK_MASK;
+#endif
 }
 
 void
@@ -1437,6 +1473,9 @@ pps_capture(struct pps_state *pps)
 	th = timehands;
 	pps->capgen = th->th_generation;
 	pps->capth = th;
+#ifdef FFCLOCK
+	pps->capffth = fftimehands;
+#endif
 	pps->capcount = th->th_counter->tc_get_timecount(th->th_counter);
 	if (pps->capgen != th->th_generation)
 		pps->capgen = 0;
@@ -1450,6 +1489,11 @@ pps_event(struct pps_state *pps, int event)
 	u_int tcount, *pcount;
 	int foff, fhard;
 	pps_seq_t *pseq;
+#ifdef FFCLOCK
+	struct timespec *tsp_ffc;
+	pps_seq_t *pseq_ffc;
+	ffcounter *ffcount;
+#endif
 
 	KASSERT(pps != NULL, ("NULL pps pointer in pps_event"));
 	/* If the timecounter was wound up underneath us, bail out. */
@@ -1464,6 +1508,11 @@ pps_event(struct pps_state *pps, int event)
 		fhard = pps->kcmode & PPS_CAPTUREASSERT;
 		pcount = &pps->ppscount[0];
 		pseq = &pps->ppsinfo.assert_sequence;
+#ifdef FFCLOCK
+		ffcount = &pps->ppsinfo_ffc.assert_ffcount;
+		tsp_ffc = &pps->ppsinfo_ffc.assert_timestamp;
+		pseq_ffc = &pps->ppsinfo_ffc.assert_sequence;
+#endif
 	} else {
 		tsp = &pps->ppsinfo.clear_timestamp;
 		osp = &pps->ppsparam.clear_offset;
@@ -1471,6 +1520,11 @@ pps_event(struct pps_state *pps, int event)
 		fhard = pps->kcmode & PPS_CAPTURECLEAR;
 		pcount = &pps->ppscount[1];
 		pseq = &pps->ppsinfo.clear_sequence;
+#ifdef FFCLOCK
+		ffcount = &pps->ppsinfo_ffc.clear_ffcount;
+		tsp_ffc = &pps->ppsinfo_ffc.clear_timestamp;
+		pseq_ffc = &pps->ppsinfo_ffc.clear_sequence;
+#endif
 	}
 
 	/*
@@ -1507,6 +1561,17 @@ pps_event(struct pps_state *pps, int event)
 			tsp->tv_sec -= 1;
 		}
 	}
+
+#ifdef FFCLOCK
+	*ffcount = pps->capffth->tick_ffcount + tcount;
+	bt = pps->capffth->tick_time;
+	ffclock_convert_delta(tcount, pps->capffth->cest.period, &bt);
+	bintime_add(&bt, &pps->capffth->tick_time);
+	bintime2timespec(&bt, &ts);
+	(*pseq_ffc)++;
+	*tsp_ffc = ts;
+#endif
+
 #ifdef PPS_SYNC
 	if (fhard) {
 		uint64_t scale;