- 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)

2 files changed, 114 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;
diff --git a/sys/sys/timepps.h b/sys/sys/timepps.h
index cde9396..8083f33 100644
--- a/sys/sys/timepps.h
+++ b/sys/sys/timepps.h
@@ -6,6 +6,12 @@
  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
  * ----------------------------------------------------------------------------
  *
+ * Copyright (c) 2011 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * Portions of this software were developed by Julien Ridoux at the University
+ * of Melbourne under sponsorship from the FreeBSD Foundation.
+ *
  * $FreeBSD$
  *
  * The is a FreeBSD version of the RFC 2783 API for Pulse Per Second 
@@ -15,6 +21,7 @@
 #ifndef _SYS_TIMEPPS_H_
 #define _SYS_TIMEPPS_H_
 
+#include <sys/_ffcounter.h>
 #include <sys/ioccom.h>
 #include <sys/time.h>
 
@@ -43,6 +50,16 @@ typedef struct {
 	int		current_mode;		/* current mode bits */
 } pps_info_t;
 
+typedef struct {
+	pps_seq_t	assert_sequence;	/* assert event seq # */
+	pps_seq_t	clear_sequence;		/* clear event seq # */
+	pps_timeu_t	assert_tu;
+	pps_timeu_t	clear_tu;
+	ffcounter	assert_ffcount;		/* ffcounter on assert event */
+	ffcounter	clear_ffcount;		/* ffcounter on clear event */
+	int		current_mode;		/* current mode bits */
+} pps_info_ffc_t;
+
 #define assert_timestamp        assert_tu.tspec
 #define clear_timestamp         clear_tu.tspec
 
@@ -79,6 +96,10 @@ typedef struct {
 #define PPS_TSFMT_TSPEC		0x1000
 #define PPS_TSFMT_NTPFP		0x2000
 
+#define	PPS_TSCLK_FBCK		0x10000
+#define	PPS_TSCLK_FFWD		0x20000
+#define	PPS_TSCLK_MASK		0x30000
+
 #define PPS_KC_HARDPPS		0
 #define PPS_KC_HARDPPS_PLL	1
 #define PPS_KC_HARDPPS_FLL	2
@@ -89,6 +110,12 @@ struct pps_fetch_args {
 	struct timespec	timeout;
 };
 
+struct pps_fetch_ffc_args {
+	int		tsformat;
+	pps_info_ffc_t	pps_info_buf_ffc;
+	struct timespec	timeout;
+};
+
 struct pps_kcbind_args {
 	int kernel_consumer;
 	int edge;
@@ -102,18 +129,21 @@ struct pps_kcbind_args {
 #define PPS_IOC_GETCAP		_IOR('1', 5, int)
 #define PPS_IOC_FETCH		_IOWR('1', 6, struct pps_fetch_args)
 #define PPS_IOC_KCBIND		_IOW('1', 7, struct pps_kcbind_args)
+#define	PPS_IOC_FETCH_FFCOUNTER	_IOWR('1', 8, struct pps_fetch_ffc_args)
 
 #ifdef _KERNEL
 
 struct pps_state {
 	/* Capture information. */
 	struct timehands *capth;
+	struct fftimehands *capffth;
 	unsigned	capgen;
 	unsigned	capcount;
 
 	/* State information. */
 	pps_params_t	ppsparam;
 	pps_info_t	ppsinfo;
+	pps_info_ffc_t	ppsinfo_ffc;
 	int		kcmode;
 	int		ppscap;
 	struct timecounter *ppstc;
@@ -184,6 +214,25 @@ time_pps_fetch(pps_handle_t handle, const int tsformat,
 }
 
 static __inline int
+time_pps_fetch_ffc(pps_handle_t handle, const int tsformat,
+	pps_info_ffc_t *ppsinfobuf, const struct timespec *timeout)
+{
+	struct pps_fetch_ffc_args arg;
+	int error;
+
+	arg.tsformat = tsformat;
+	if (timeout == NULL) {
+		arg.timeout.tv_sec = -1;
+		arg.timeout.tv_nsec = -1;
+	} else {
+		arg.timeout = *timeout;
+	}
+	error = ioctl(handle, PPS_IOC_FETCH_FFCOUNTER, &arg);
+	*ppsinfobuf = arg.pps_info_buf_ffc;
+	return (error);
+}
+
+static __inline int
 time_pps_kcbind(pps_handle_t handle, const int kernel_consumer,
 	const int edge, const int tsformat)
 {