diff options
Diffstat (limited to 'sys/kern/subr_rtc.c')
| -rw-r--r-- | sys/kern/subr_rtc.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/sys/kern/subr_rtc.c b/sys/kern/subr_rtc.c new file mode 100644 index 0000000..ed2befc --- /dev/null +++ b/sys/kern/subr_rtc.c @@ -0,0 +1,178 @@ +/*- + * Copyright (c) 1988 University of Utah. + * Copyright (c) 1982, 1990, 1993 + * The Regents of the University of California. + * Copyright (c) 2011 The FreeBSD Foundation + * 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. + * + * Portions of this software were developed by Julien Ridoux at the University + * of Melbourne under sponsorship from the FreeBSD Foundation. + * + * 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. + * 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 + */ + +/* + * 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_ffclock.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/bus.h> +#include <sys/clock.h> +#include <sys/sysctl.h> +#ifdef FFCLOCK +#include <sys/timeffc.h> +#endif +#include <sys/timetc.h> + +#include "clock_if.h" + +static device_t clock_dev = NULL; +static long clock_res; +static struct timespec clock_adj; + +/* XXX: should be kern. now, it's no longer machdep. */ +static int disable_rtc_set; +SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set, CTLFLAG_RW, &disable_rtc_set, + 0, "Disallow adjusting time-of-day clock"); + +void +clock_register(device_t dev, long res) /* res has units of microseconds */ +{ + + 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; + } + 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; + clock_adj.tv_sec = res / 2 / 1000000; + clock_adj.tv_nsec = res / 2 % 1000000 * 1000; + if (bootverbose) + device_printf(dev, "registered as a time-of-day clock " + "(resolution %ldus, adjustment %jd.%09jds)\n", res, + (intmax_t)clock_adj.tv_sec, (intmax_t)clock_adj.tv_nsec); +} + +/* + * 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 ts; + int error; + + if (clock_dev == NULL) { + printf("warning: no time-of-day clock registered, system time " + "will not be set accurately\n"); + goto wrong_time; + } + /* XXX: We should poll all registered RTCs in case of failure */ + 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); + goto wrong_time; + } + if (error == EINVAL || ts.tv_sec < 0) { + printf("Invalid time in real time clock.\n" + "Check and reset the date immediately!\n"); + goto wrong_time; + } + + ts.tv_sec += utc_offset(); + timespecadd(&ts, &clock_adj); + tc_setclock(&ts); +#ifdef FFCLOCK + ffclock_reset_clock(&ts); +#endif + return; + +wrong_time: + if (base > 0) { + ts.tv_sec = base; + ts.tv_nsec = 0; + tc_setclock(&ts); + } +} + +/* + * Write system time back to RTC + */ +void +resettodr(void) +{ + struct timespec ts; + int error; + + if (disable_rtc_set || clock_dev == NULL) + return; + + getnanotime(&ts); + timespecadd(&ts, &clock_adj); + ts.tv_sec -= utc_offset(); + /* XXX: We should really set all registered RTCs */ + 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); +} |
