4.4BSD/usr/src/sys/news3400/news3400/clock.c
/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1992, 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, Ralph Campbell, and Kazumasa Utashiro of
* Software Research Associates, Inc.
*
* 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 $Hdr: clock.c 1.18 91/01/21$
*
* @(#)clock.c 8.1 (Berkeley) 6/11/93
*/
#include <machine/adrsmap.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <news3400/news3400/clockreg.h>
/*
* Machine-dependent clock routines.
*
* Startrtclock restarts the real-time clock, which provides
* hardclock interrupts to kern_clock.c.
*
* Inittodr initializes the time of day hardware which provides
* date functions. Its primary function is to use some file
* system information in case the hardare clock lost state.
*
* Resettodr restores the time of day hardware after a time change.
*/
/*
* We assume newhz is either stathz or profhz, and that neither will
* change after being set up above. Could recalculate intervals here
* but that would be a drag.
*/
void
setstatclockrate(newhz)
int newhz;
{
/* KU:XXX do something! */
}
/*
* Set up the real-time and statistics clocks. Leave stathz 0 only if
* no alternative timer is available.
*/
cpu_initclocks()
{
/*
* Start the real-time clock.
*/
*(char *)ITIMER = IOCLOCK / 6144 / 100 - 1;
/*
* Enable the real-time clock.
*/
*(char *)INTEN0 |= (char)INTEN0_TIMINT;
}
/*
* This code is defunct after 2099.
* Will Unix still be here then??
*/
static short dayyr[12] = {
0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
};
#define bcd_to_int(BCD) (i = BCD, (((i) >> 4) & 0xf) * 10 + ((i) & 0xf))
#define int_to_bcd(INT) (i = INT, ((((i) / 10) % 10) << 4) + (i) % 10)
/*
* Initialze the time of day register, based on the time base which is, e.g.
* from a filesystem. Base provides the time to within six months,
* and the time of year clock (if any) provides the rest.
*/
inittodr(base)
time_t base;
{
register volatile u_char *rtc_port = (u_char *)RTC_PORT;
register volatile u_char *rtc_data = (u_char *)DATA_PORT;
register int days, yr;
int sec, min, hour, week, day, mon, year;
long deltat, badbase = 0;
register u_int i;
if (base < 5*SECYR) {
printf("WARNING: preposterous time in file system\n");
/* read the system clock anyway */
base = 6*SECYR + 186*SECDAY + SECDAY/2;
badbase = 1;
}
*rtc_port = READ_CLOCK;
sec = bcd_to_int(*rtc_data++);
min = bcd_to_int(*rtc_data++);
hour = bcd_to_int(*rtc_data++);
week = bcd_to_int(*rtc_data++);
day = bcd_to_int(*rtc_data++);
mon = bcd_to_int(*rtc_data++);
year = bcd_to_int(*rtc_data++);
*rtc_port = 0;
/* simple sanity checks */
if (year < 70 || mon < 1 || mon > 12 || day < 1 || day > 31 ||
hour > 23 || min > 59 || sec > 59) {
printf("WARNING: preposterous clock chip time\n");
/*
* Believe the time in the file system for lack of
* anything better, resetting the TODR.
*/
time.tv_sec = base;
if (!badbase)
resettodr();
return (0);
}
days = 0;
for (yr = 70; yr < year; yr++)
days += LEAPYEAR(yr) ? 366 : 365;
days += dayyr[mon - 1] + day - 1;
if (LEAPYEAR(yr) && mon > 2)
days++;
/* now have days since Jan 1, 1970; the rest is easy... */
time.tv_sec = days * SECDAY + hour * 3600 + min * 60 + sec;
if (!badbase) {
/*
* See if we gained/lost two or more days;
* if so, assume something is amiss.
*/
deltat = time.tv_sec - base;
if (deltat < 0)
deltat = -deltat;
if (deltat < 2 * SECDAY)
return;
printf("WARNING: clock %s %d days",
time.tv_sec < base ? "lost" : "gained", deltat / SECDAY);
}
printf(" -- CHECK AND RESET THE DATE!\n");
}
/*
* Reset the TODR based on the time value; used when the TODR
* has a preposterous value and also when the time is reset
* by the stime system call. Also called when the TODR goes past
* TODRZERO + 100*(SECYEAR+2*SECDAY) (e.g. on Jan 2 just after midnight)
* to wrap the TODR around.
*/
resettodr()
{
register volatile u_char *rtc_port = (u_char *)RTC_PORT;
register volatile u_char *rtc_data = (u_char *)DATA_PORT;
int sec, min, hour, week, day, mon, year;
register int t, t2, t3;
register int i;
/* compute the year */
t2 = time.tv_sec / SECDAY;
t = 69;
while (t2 >= 0) { /* whittle off years */
t3 = t2;
t++;
t2 -= LEAPYEAR(t) ? 366 : 365;
}
year = t;
/* t3 = month + day; separate */
t = LEAPYEAR(t);
for (t2 = 1; t2 < 12; t2++)
if (t3 < dayyr[t2] + (t && t2 > 1))
break;
/* t2 is month */
mon = t2;
t3 = t3 - dayyr[t2 - 1] + 1;
if (t && t2 > 2)
t3--;
day = t3;
week = 0;
/* the rest is easy */
t = time.tv_sec % SECDAY;
hour = t / 3600;
t %= 3600;
min = t / 60;
sec = t % 60;
*rtc_port = SET_CLOCK;
*rtc_data++ = int_to_bcd(sec);
*rtc_data++ = int_to_bcd(min);
*rtc_data++ = int_to_bcd(hour);
*rtc_data++ = int_to_bcd(week);
*rtc_data++ = int_to_bcd(day);
*rtc_data++ = int_to_bcd(mon);
*rtc_data = int_to_bcd(year);
*rtc_port = 0;
}