Add a generic implementation of inittodr() and resettodr(), as well as

a set of helper routines to deal with real-time clocks. The generic
functions access the clock diver using a kobj interface. This is intended
to reduce code reduplication and make it easy to support more than one
clock model on a single architecture.

This code is currently only used on sparc64, but it is planned to convert
the code of the other architectures to it later.

1 files changed, 316 insertions, 0 deletions

diff --git a/sys/kern/subr_clock.c b/sys/kern/subr_clock.c
new file mode 100644
index 0000000..a79e331
--- /dev/null
+++ b/sys/kern/subr_clock.c
@@ -0,0 +1,316 @@
+/*
+ * Copyright (c) 1988 University of Utah.
+ * Copyright (c) 1982, 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * the Systems Programming Group of the University of Utah Computer
+ * Science Department.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	from: Utah $Hdr: clock.c 1.18 91/01/21$
+ *	from: @(#)clock.c	8.2 (Berkeley) 1/12/94
+ *	from: NetBSD: clock_subr.c,v 1.6 2001/07/07 17:04:02 thorpej Exp
+ *	and
+ *	from: src/sys/i386/isa/clock.c,v 1.176 2001/09/04
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Helpers for time-of-day clocks. This is useful for architectures that need
+ * support multiple models of such clocks, and generally serves to make the
+ * code more machine-independent.
+ * If the clock in question can also be used as a time counter, the driver
+ * needs to initiate this.
+ * This code is not yet used by all architectures.
+ */
+
+/*
+ * Generic routines to convert between a POSIX date
+ * (seconds since 1/1/1970) and yr/mo/day/hr/min/sec
+ * Derived from NetBSD arch/hp300/hp300/clock.c
+ */
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/bus.h>
+#include <sys/clock.h>
+#include <sys/sysctl.h>
+#include <sys/timetc.h>
+
+#include "clock_if.h"
+
+static __inline int leapyear(int year);
+static int sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS);
+
+#define	FEBRUARY	2
+#define	days_in_year(y) 	(leapyear(y) ? 366 : 365)
+#define	days_in_month(y, m) \
+	(month_days[(m) - 1] + (m == FEBRUARY ? leapyear(y) : 0))
+/* Day of week. Days are counted from 1/1/1970, which was a Thursday */
+#define	day_of_week(days)	(((days) + 4) % 7)
+
+static const int month_days[12] = {
+	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
+};
+
+static device_t clock_dev = NULL;
+static long clock_res;
+
+int adjkerntz;		/* local offset from GMT in seconds */
+int disable_rtc_set;	/* disable resettodr() if != 0 */
+int wall_cmos_clock;	/* wall CMOS clock assumed if != 0 */
+
+/*
+ * These have traditionally been in machdep, but should probably be moved to
+ * kern.
+ */
+SYSCTL_PROC(_machdep, OID_AUTO, adjkerntz, CTLTYPE_INT|CTLFLAG_RW,
+	&adjkerntz, 0, sysctl_machdep_adjkerntz, "I", "");
+
+SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set,
+	CTLFLAG_RW, &disable_rtc_set, 0, "");
+
+SYSCTL_INT(_machdep, OID_AUTO, wall_cmos_clock,
+	CTLFLAG_RW, &wall_cmos_clock, 0, "");
+
+static int
+sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS)
+{
+	int error;
+	error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2,
+		req);
+	if (!error && req->newptr)
+		resettodr();
+	return (error);
+}
+
+/*
+ * This inline avoids some unnecessary modulo operations
+ * as compared with the usual macro:
+ *   ( ((year % 4) == 0 &&
+ *      (year % 100) != 0) ||
+ *     ((year % 400) == 0) )
+ * It is otherwise equivalent.
+ */
+static __inline int
+leapyear(int year)
+{
+	int rv = 0;
+
+	if ((year & 3) == 0) {
+		rv = 1;
+		if ((year % 100) == 0) {
+			rv = 0;
+			if ((year % 400) == 0)
+				rv = 1;
+		}
+	}
+	return (rv);
+}
+
+int
+clock_ct_to_ts(struct clocktime *ct, struct timespec *ts)
+{
+	time_t secs;
+	int i, year, days;
+
+	year = ct->year;
+
+	/* Sanity checks. */
+	if (ct->mon < 1 || ct->mon > 12 || ct->day < 1 ||
+	    ct->day > days_in_month(year, ct->mon) ||
+	    ct->hour > 23 ||  ct->min > 59 || ct->sec > 59 ||
+	    ct->year > 2037)		/* time_t overflow */
+		return (EINVAL);
+
+	/*
+	 * Compute days since start of time
+	 * First from years, then from months.
+	 */
+	days = 0;
+	for (i = POSIX_BASE_YEAR; i < year; i++)
+		days += days_in_year(i);
+
+	/* Months */
+	for (i = 1; i < ct->mon; i++)
+	  	days += days_in_month(year, i);
+	days += (ct->day - 1);
+
+	/* Another sanity check. */
+	if (ct->dow != -1 && ct->dow != day_of_week(days))
+		return (EINVAL);
+
+	/* Add hours, minutes, seconds. */
+	secs = ((days * 24 + ct->hour) * 60 + ct->min) * 60 + ct->sec;
+
+	ts->tv_sec = secs;
+	ts->tv_nsec = ct->nsec;
+	return (0);
+}
+
+void
+clock_ts_to_ct(struct timespec *ts, struct clocktime *ct)
+{
+	int i, year, days;
+	time_t rsec;	/* remainder seconds */
+	time_t secs;
+
+	secs = ts->tv_sec;
+	days = secs / SECDAY;
+	rsec = secs % SECDAY;
+
+	ct->dow = day_of_week(days);
+
+	/* Subtract out whole years, counting them in i. */
+	for (year = POSIX_BASE_YEAR; days >= days_in_year(year); year++)
+		days -= days_in_year(year);
+	ct->year = year;
+
+	/* Subtract out whole months, counting them in i. */
+	for (i = 1; days >= days_in_month(year, i); i++)
+		days -= days_in_month(year, i);
+	ct->mon = i;
+
+	/* Days are what is left over (+1) from all that. */
+	ct->day = days + 1;
+
+	/* Hours, minutes, seconds are easy */
+	ct->hour = rsec / 3600;
+	rsec = rsec % 3600;
+	ct->min  = rsec / 60;
+	rsec = rsec % 60;
+	ct->sec  = rsec;
+	ct->nsec = ts->tv_nsec;
+}
+
+void
+clock_register(device_t dev, long res)
+{
+
+	if (clock_dev != NULL) {
+		if (clock_res > res) {
+			if (bootverbose) {
+				device_printf(dev, "not installed as "
+				    "time-of-day clock: clock %s has higher "
+				    "resolution\n", device_get_name(clock_dev));
+			}
+			return;
+		} else {
+			if (bootverbose) {
+				device_printf(clock_dev, "removed as "
+				    "time-of-day clock: clock %s has higher "
+				    "resolution\n", device_get_name(dev));
+			}
+		}
+	}
+	clock_dev = dev;
+	clock_res = res;
+	if (bootverbose) {
+		device_printf(dev, "registered as a time-of-day clock "
+		    "(resolution %ldus)\n", res);
+	}
+}
+
+/*
+ * inittodr and settodr derived from the i386 versions written
+ * by Christoph Robitschko <chmr@edvz.tu-graz.ac.at>,  reintroduced and
+ * updated by Chris Stenton <chris@gnome.co.uk> 8/10/94
+ */
+
+/*
+ * Initialize the time of day register, based on the time base which is, e.g.
+ * from a filesystem.
+ */
+void
+inittodr(time_t base)
+{
+	struct timespec diff, ref, ts;
+	int error;
+
+	if (base) {
+		ref.tv_sec = base;
+		ref.tv_nsec = 0;
+		tc_setclock(&ref);
+	}
+
+	if (clock_dev == NULL) {
+		printf("warning: no time-of-day clock registered, system time "
+		    "will not be set accurately\n");
+		return;
+	}
+	error = CLOCK_GETTIME(clock_dev, &ts);
+	if (error != 0 && error != EINVAL) {
+		printf("warning: clock_gettime failed (%d), the system time "
+		    "will not be set accurately\n", error);
+		return;
+	}
+	if (error == EINVAL || ts.tv_sec < 0) {
+		printf("Invalid time in real time clock.\n");
+		printf("Check and reset the date immediately!\n");
+	}
+
+	ts.tv_sec += tz.tz_minuteswest * 60 +
+	    (wall_cmos_clock ? adjkerntz : 0);
+
+	if (timespeccmp(&ref, &ts, >)) {
+		diff = ref;
+		timespecsub(&ref, &ts);
+	} else {
+		diff = ts;
+		timespecsub(&diff, &ref);
+	}
+	if (ts.tv_sec >= 2) {
+		/* badly off, adjust it */
+		tc_setclock(&ts);
+	}
+}
+
+/*
+ * Write system time back to RTC
+ */
+void
+resettodr()
+{
+	struct timespec ts;
+	int error;
+
+	if (disable_rtc_set || clock_dev == NULL)
+		return;
+
+	getnanotime(&ts);
+	ts.tv_sec -= tz.tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0);
+	if ((error = CLOCK_SETTIME(clock_dev, &ts)) != 0) {
+		printf("warning: clock_settime failed (%d), time-of-day clock "
+		    "not adjusted to system time\n", error);
+		return;
+	}
+}