/* * 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 and Ralph Campbell. * * 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) 6/10/93 */ #include <sys/param.h> #include <sys/kernel.h> #include <machine/machConst.h> #include <pmax/pmax/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. */ volatile struct chiptime *Mach_clock_addr; /* * Start the real-time and statistics clocks. Leave stathz 0 since there * are no other timers available. */ cpu_initclocks() { register volatile struct chiptime *c; extern int tickadj; tick = 15625; /* number of micro-seconds between interrupts */ hz = 1000000 / 15625; /* 64 Hz */ tickadj = 240000 / (60000000 / 15625); c = Mach_clock_addr; c->rega = REGA_TIME_BASE | SELECTED_RATE; c->regb = REGB_PER_INT_ENA | REGB_DATA_MODE | REGB_HOURS_FORMAT; } /* * 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; { } /* * 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 }; /* * 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. */ void inittodr(base) time_t base; { register volatile struct chiptime *c; register int days, yr; int sec, min, hour, day, mon, year; long deltat; int badbase, s; if (base < 5*SECYR) { printf("WARNING: preposterous time in file system"); /* read the system clock anyway */ base = 6*SECYR + 186*SECDAY + SECDAY/2; badbase = 1; } else badbase = 0; c = Mach_clock_addr; /* don't read clock registers while they are being updated */ s = splclock(); while ((c->rega & REGA_UIP) == 1) ; sec = c->sec; min = c->min; hour = c->hour; day = c->day; mon = c->mon; year = c->year + 20; /* must be multiple of 4 because chip knows leap */ splx(s); /* simple sanity checks */ if (year < 70 || mon < 1 || mon > 12 || day < 1 || day > 31 || hour > 23 || min > 59 || sec > 59) { /* * Believe the time in the file system for lack of * anything better, resetting the TODR. */ time.tv_sec = base; if (!badbase) { printf("WARNING: preposterous clock chip time\n"); resettodr(); } goto bad; } 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); } bad: 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 struct chiptime *c; register int t, t2; int sec, min, hour, day, mon, year; int s; /* compute the year */ t2 = time.tv_sec / SECDAY; year = 69; while (t2 >= 0) { /* whittle off years */ t = t2; year++; t2 -= LEAPYEAR(year) ? 366 : 365; } /* t = month + day; separate */ t2 = LEAPYEAR(year); for (mon = 1; mon < 12; mon++) if (t < dayyr[mon] + (t2 && mon > 1)) break; day = t - dayyr[mon - 1] + 1; if (t2 && mon > 2) day--; /* the rest is easy */ t = time.tv_sec % SECDAY; hour = t / 3600; t %= 3600; min = t / 60; sec = t % 60; c = Mach_clock_addr; s = splclock(); t = c->regb; c->regb = t | REGB_SET_TIME; MachEmptyWriteBuffer(); c->sec = sec; c->min = min; c->hour = hour; c->day = day; c->mon = mon; c->year = year - 20; /* must be multiple of 4 because chip knows leap */ c->regb = t; MachEmptyWriteBuffer(); splx(s); }