/*- * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * William Jolitz and Don Ahn. * * 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. * * @(#)clock.c 7.2 (Berkeley) 5/12/91 * * PATCHES MAGIC LEVEL PATCH THAT GOT US HERE * -------------------- ----- ---------------------- * CURRENT PATCH LEVEL: 3 00082 * -------------------- ----- ---------------------- * * 14 Aug 92 Arne Henrik Juul Added code in the kernel to * allow for DST in the BIOS. * 17 Jan 93 Bruce Evans Fixed leap year and second * calculations * 01 Feb 93 Julian Elischer Added code to for the cpu * speed independent spinwait() * function, (used by scsi and others) */ /* * Primitive clock interrupt routines. */ #include "param.h" #include "systm.h" #include "time.h" #include "kernel.h" #include "machine/segments.h" #include "i386/isa/icu.h" #include "i386/isa/isa.h" #include "i386/isa/rtc.h" #include "i386/isa/timerreg.h" #define DAYST 119 #define DAYEN 303 #ifndef XTALSPEED #define XTALSPEED 1193182 #endif startrtclock() { int s; findcpuspeed(); /* use the clock (while it's free) to find the cpu speed */ /* initialize 8253 clock */ outb(TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT); /* Correct rounding will buy us a better precision in timekeeping */ outb (IO_TIMER1, (XTALSPEED+hz/2)/hz); outb (IO_TIMER1, ((XTALSPEED+hz/2)/hz)/256); /* initialize brain-dead battery powered clock */ outb (IO_RTC, RTC_STATUSA); outb (IO_RTC+1, 0x26); outb (IO_RTC, RTC_STATUSB); outb (IO_RTC+1, 2); outb (IO_RTC, RTC_DIAG); if (s = inb (IO_RTC+1)) printf("RTC BIOS diagnostic error %b\n", s, RTCDG_BITS); outb (IO_RTC, RTC_DIAG); outb (IO_RTC+1, 0); } unsigned int delaycount; /* calibrated loop variable (1 millisecond) */ #define FIRST_GUESS 0x2000 findcpuspeed() { unsigned char low; unsigned int remainder; /* Put counter in count down mode */ outb(IO_TIMER1+3, 0x34); outb(IO_TIMER1, 0xff); outb(IO_TIMER1, 0xff); delaycount = FIRST_GUESS; spinwait(1); /* Read the value left in the counter */ low = inb(IO_TIMER1); /* least siginifcant */ remainder = inb(IO_TIMER1); /* most significant */ remainder = (remainder<<8) + low ; /* Formula for delaycount is : * (loopcount * timer clock speed)/ (counter ticks * 1000) */ delaycount = (FIRST_GUESS * (XTALSPEED/1000)) / (0xffff-remainder); } /* convert 2 digit BCD number */ bcd(i) int i; { return ((i/16)*10 + (i%16)); } /* convert years to seconds (from 1970) */ unsigned long ytos(y) int y; { int i; unsigned long ret; ret = 0; for(i = 1970; i < y; i++) { if (i % 4) ret += 365*24*60*60; else ret += 366*24*60*60; } return ret; } /* convert months to seconds */ unsigned long mtos(m,leap) int m,leap; { int i; unsigned long ret; ret = 0; for(i=1;i= DAYST) && ( yd <= DAYEN)) { sec -= 60*60; } sec += tz.tz_minuteswest * 60; time.tv_sec = sec; } #ifdef garbage /* * Initialze the time of day register, based on the time base which is, e.g. * from a filesystem. */ test_inittodr(base) time_t base; { outb(IO_RTC,9); /* year */ printf("%d ",bcd(inb(IO_RTC+1))); outb(IO_RTC,8); /* month */ printf("%d ",bcd(inb(IO_RTC+1))); outb(IO_RTC,7); /* day */ printf("%d ",bcd(inb(IO_RTC+1))); outb(IO_RTC,4); /* hour */ printf("%d ",bcd(inb(IO_RTC+1))); outb(IO_RTC,2); /* minutes */ printf("%d ",bcd(inb(IO_RTC+1))); outb(IO_RTC,0); /* seconds */ printf("%d\n",bcd(inb(IO_RTC+1))); time.tv_sec = base; } #endif /* * Restart the clock. */ resettodr() { } /* * Wire clock interrupt in. */ #define V(s) __CONCAT(V, s) extern V(clk)(); enablertclock() { INTREN(IRQ0); setidt(ICU_OFFSET+0, &V(clk), SDT_SYS386IGT, SEL_KPL); splnone(); } spinwait(millisecs) int millisecs; /* number of milliseconds to delay */ { int i, j; for (i=0;i