Automatically degrade the timedelta sensor if the clock is free running for to

long (12 hours for most cards, four days for the ones with higher precision
local clocks, e.g. the GPS170PCI).

All radio-clock drivers now behave more or less the same with regarding to
timedelta sensor degradation;  time to implement a few new drivers...

1 files changed, 42 insertions, 4 deletions

diff --git a/sys/dev/pci/mbg.c b/sys/dev/pci/mbg.c
index bf84eb27e02..05a6a0a9b0b 100644
--- a/sys/dev/pci/mbg.c
+++ b/sys/dev/pci/mbg.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mbg.c,v 1.23 2007/11/12 16:40:46 mbalmer Exp $ */
+/*	$OpenBSD: mbg.c,v 1.24 2007/11/26 19:44:43 mbalmer Exp $ */
 
 /*
  * Copyright (c) 2006, 2007 Marc Balmer <mbalmer@openbsd.org>
@@ -47,7 +47,9 @@ struct mbg_softc {
 	struct ksensor		sc_timedelta;
 	struct ksensor		sc_signal;
 	struct ksensordev	sc_sensordev;
-
+	struct timeout		sc_timeout;	/* invalidate sensor */
+	int			sc_trust;	/* trust time in ticks */
+	
 	int			(*sc_read)(struct mbg_softc *, int cmd,
 				    char *buf, size_t len,
 				    struct timespec *tstamp);
@@ -144,6 +146,7 @@ int	mbg_read_amcc_s5933(struct mbg_softc *, int cmd, char *buf, size_t len,
 	    struct timespec *tstamp);
 int	mbg_read_asic(struct mbg_softc *, int cmd, char *buf, size_t len,
 	    struct timespec *tstamp);
+void	mbg_timeout(void *);
 
 struct cfattach mbg_ca = {
 	sizeof(struct mbg_softc), mbg_probe, mbg_attach
@@ -174,14 +177,17 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 	struct mbg_softc *sc = (struct mbg_softc *)self;
 	struct pci_attach_args *const pa = (struct pci_attach_args *)aux;
 	struct mbg_time tframe;
+	struct timeval tv_trust;
 	pcireg_t memtype;
 	bus_size_t iosize, iosize2;
-	int bar = PCI_MAPREG_START, signal;
+	int bar = PCI_MAPREG_START, signal, t_trust;
 	const char *desc;
 #ifdef MBG_DEBUG
 	char fw_id[MBG_ID_LEN];
 #endif
 
+	timeout_set(&sc->sc_timeout, mbg_timeout, sc);
+
 	/* for the PEX511 use BAR2 instead of BAR0*/
 	if (PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_MEINBERG_PEX511)
 		bar += 0x08;
@@ -202,6 +208,7 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 	    sizeof(sc->sc_sensordev.xname));
 
 	sc->sc_timedelta.type = SENSOR_TIMEDELTA;
+	sc->sc_timedelta.status = SENSOR_S_UNKNOWN;
 	sc->sc_timedelta.value = 0LL;
 	sc->sc_timedelta.flags = 0;
 	sensor_attach(&sc->sc_sensordev, &sc->sc_timedelta);
@@ -213,6 +220,8 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 	strlcpy(sc->sc_signal.desc, "Signal", sizeof(sc->sc_signal.desc));
 	sensor_attach(&sc->sc_sensordev, &sc->sc_signal);
 
+	t_trust = 12 * 60 * 60;		/* twelve hours */
+
 	switch (PCI_PRODUCT(pa->pa_id)) {
 	case PCI_PRODUCT_MEINBERG_PCI32:
 		sc->sc_read = mbg_read_amcc_s5933;
@@ -243,6 +252,7 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 		sensor_task_register(sc, mbg_task, 10);
 		break;
 	case PCI_PRODUCT_MEINBERG_GPS170PCI:
+		t_trust = 4 * 24 * 60 * 60;	/* four days */
 		sc->sc_read = mbg_read_asic;
 		sensor_task_register(sc, mbg_task_hr, 1);
 		break;
@@ -252,6 +262,10 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 		break;
 	}
 
+	tv_trust.tv_sec = t_trust;
+	tv_trust.tv_usec = 0L;
+	sc->sc_trust = tvtohz(&tv_trust);
+
 	if (sc->sc_read(sc, MBG_GET_TIME, (char *)&tframe,
 	    sizeof(struct mbg_time), NULL)) {
 		printf(": unknown status");
@@ -288,6 +302,7 @@ mbg_attach(struct device *parent, struct device *self, void *aux)
 #endif
 	printf("\n");
 	sensordev_install(&sc->sc_sensordev);
+	timeout_add(&sc->sc_timeout, sc->sc_trust);
 }
 
 /*
@@ -366,7 +381,6 @@ mbg_update_sensor(struct mbg_softc *sc, struct timespec *tstamp,
 	int signal;
 
 	sc->sc_timedelta.value = timedelta;
-	sc->sc_timedelta.status = SENSOR_S_OK;
 	sc->sc_timedelta.tv.tv_sec = tstamp->tv_sec;
 	sc->sc_timedelta.tv.tv_usec = tstamp->tv_nsec / 1000;
 
@@ -381,6 +395,10 @@ mbg_update_sensor(struct mbg_softc *sc, struct timespec *tstamp,
 	    SENSOR_S_WARN : SENSOR_S_OK;
 	sc->sc_signal.tv.tv_sec = sc->sc_timedelta.tv.tv_sec;
 	sc->sc_signal.tv.tv_usec = sc->sc_timedelta.tv.tv_usec;
+	if (!(status & MBG_FREERUN)) {
+		sc->sc_timedelta.status = SENSOR_S_OK;
+		timeout_add(&sc->sc_timeout, sc->sc_trust);
+	}
 }
 
 /*
@@ -545,3 +563,23 @@ mbg_read_asic(struct mbg_softc *sc, int cmd, char *buf, size_t len,
 	}
 	return 0;
 }
+
+/*
+ * Degrade the sensor state if we are feerunning for more than
+ * TRUSTTIME seconds.
+ */
+void
+mbg_timeout(void *xsc)
+{
+	struct mbg_softc *sc = xsc;
+
+	if (sc->sc_timedelta.status == SENSOR_S_OK) {
+		sc->sc_timedelta.status = SENSOR_S_WARN;
+		/*
+		 * further degrade in TRUSTTIME seconds if no new valid NMEA
+		 * sentences are received.
+		 */
+		timeout_add(&sc->sc_timeout, sc->sc_trust);
+	} else
+		sc->sc_timedelta.status = SENSOR_S_CRIT;
+}