884 lines
22 KiB
C
884 lines
22 KiB
C
/* $NetBSD: clock.c,v 1.70 2002/01/01 09:14:14 perry Exp $ */
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/*-
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* Copyright (c) 1993, 1994 Charles M. Hannum.
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* Copyright (c) 1990 The Regents of the University of California.
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* All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* William Jolitz and Don Ahn.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)clock.c 7.2 (Berkeley) 5/12/91
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*/
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/*
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* Mach Operating System
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* Copyright (c) 1991,1990,1989 Carnegie Mellon University
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* All Rights Reserved.
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*
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* Permission to use, copy, modify and distribute this software and its
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* documentation is hereby granted, provided that both the copyright
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* notice and this permission notice appear in all copies of the
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* software, derivative works or modified versions, and any portions
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* thereof, and that both notices appear in supporting documentation.
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*
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* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
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* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
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* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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*
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* Carnegie Mellon requests users of this software to return to
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*
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* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
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* School of Computer Science
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* Carnegie Mellon University
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* Pittsburgh PA 15213-3890
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*
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* any improvements or extensions that they make and grant Carnegie Mellon
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* the rights to redistribute these changes.
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*/
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/*
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Copyright 1988, 1989 by Intel Corporation, Santa Clara, California.
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All Rights Reserved
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Permission to use, copy, modify, and distribute this software and
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its documentation for any purpose and without fee is hereby
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granted, provided that the above copyright notice appears in all
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copies and that both the copyright notice and this permission notice
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appear in supporting documentation, and that the name of Intel
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not be used in advertising or publicity pertaining to distribution
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of the software without specific, written prior permission.
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INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
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INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
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IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
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CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
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LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
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NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
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WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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/*
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* Primitive clock interrupt routines.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.70 2002/01/01 09:14:14 perry Exp $");
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/* #define CLOCKDEBUG */
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/* #define CLOCK_PARANOIA */
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/time.h>
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#include <sys/kernel.h>
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#include <sys/device.h>
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#include <machine/cpu.h>
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#include <machine/intr.h>
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#include <machine/pio.h>
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#include <machine/cpufunc.h>
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#include <dev/isa/isareg.h>
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#include <dev/isa/isavar.h>
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#include <dev/ic/mc146818reg.h>
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#include <i386/isa/nvram.h>
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#include <i386/isa/timerreg.h>
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#include <dev/clock_subr.h>
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#include "mca.h"
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#if NMCA > 0
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#include <machine/mca_machdep.h> /* for MCA_system */
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#endif
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#include "pcppi.h"
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#if (NPCPPI > 0)
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#include <dev/isa/pcppivar.h>
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#ifdef CLOCKDEBUG
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int clock_debug = 0;
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#define DPRINTF(arg) if (clock_debug) printf arg
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#else
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#define DPRINTF(arg)
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#endif
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int sysbeepmatch __P((struct device *, struct cfdata *, void *));
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void sysbeepattach __P((struct device *, struct device *, void *));
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struct cfattach sysbeep_ca = {
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sizeof(struct device), sysbeepmatch, sysbeepattach
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};
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static int ppi_attached;
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static pcppi_tag_t ppicookie;
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#endif /* PCPPI */
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void spinwait __P((int));
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int clockintr __P((void *));
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int gettick __P((void));
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void sysbeep __P((int, int));
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void rtcinit __P((void));
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int rtcget __P((mc_todregs *));
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void rtcput __P((mc_todregs *));
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int bcdtobin __P((int));
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int bintobcd __P((int));
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static void check_clock_bug __P((void));
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static inline int gettick_broken_latch __P((void));
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__inline u_int mc146818_read __P((void *, u_int));
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__inline void mc146818_write __P((void *, u_int, u_int));
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__inline u_int
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mc146818_read(sc, reg)
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void *sc; /* XXX use it? */
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u_int reg;
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{
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outb(IO_RTC, reg);
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return (inb(IO_RTC+1));
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}
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__inline void
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mc146818_write(sc, reg, datum)
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void *sc; /* XXX use it? */
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u_int reg, datum;
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{
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outb(IO_RTC, reg);
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outb(IO_RTC+1, datum);
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}
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static u_long rtclock_tval;
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static int clock_broken_latch = 0;
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#ifdef CLOCK_PARANOIA
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static int ticks[6];
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#endif
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/*
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* i8254 latch check routine:
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* National Geode (formerly Cyrix MediaGX) has a serious bug in
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* its built-in i8254-compatible clock module.
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* Set the variable 'clock_broken_latch' to indicate it.
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* XXX check only cpu_id
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*/
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static void
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check_clock_bug()
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{
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extern int cpu_id;
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switch (cpu_id) {
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case 0x440: /* Cyrix MediaGX */
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case 0x540: /* GXm */
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clock_broken_latch = 1;
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break;
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default:
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clock_broken_latch = 0;
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break;
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}
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}
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int
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gettick_broken_latch()
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{
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u_long ef;
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int v1, v2, v3;
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int w1, w2, w3;
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/* Don't want someone screwing with the counter
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while we're here. */
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ef = read_eflags();
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disable_intr();
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v1 = inb(TIMER_CNTR0);
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v1 |= inb(TIMER_CNTR0) << 8;
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v2 = inb(TIMER_CNTR0);
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v2 |= inb(TIMER_CNTR0) << 8;
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v3 = inb(TIMER_CNTR0);
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v3 |= inb(TIMER_CNTR0) << 8;
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write_eflags(ef);
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#ifdef CLOCK_PARANOIA
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if (clock_debug) {
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ticks[0] = ticks[3];
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ticks[1] = ticks[4];
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ticks[2] = ticks[5];
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ticks[3] = v1;
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ticks[4] = v2;
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ticks[5] = v3;
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}
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#endif
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if (v1 >= v2 && v2 >= v3 && v1 - v3 < 0x200)
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return (v2);
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#define _swap_val(a, b) do { \
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int c = a; \
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a = b; \
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b = c; \
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} while (0)
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/*
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* sort v1 v2 v3
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*/
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if (v1 < v2)
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_swap_val(v1, v2);
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if (v2 < v3)
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_swap_val(v2, v3);
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if (v1 < v2)
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_swap_val(v1, v2);
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/*
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* compute the middle value
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*/
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if (v1 - v3 < 0x200)
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return (v2);
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w1 = v2 - v3;
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w2 = v3 - v1 + rtclock_tval;
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w3 = v1 - v2;
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if (w1 >= w2) {
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if (w1 >= w3)
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return (v1);
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} else {
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if (w2 >= w3)
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return (v2);
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}
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return (v3);
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}
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/* minimal initialization, enough for delay() */
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void
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initrtclock()
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{
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u_long tval;
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/*
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* Compute timer_count, the count-down count the timer will be
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* set to. Also, correctly round
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* this by carrying an extra bit through the division.
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*/
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tval = (TIMER_FREQ * 2) / (u_long) hz;
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tval = (tval / 2) + (tval & 0x1);
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/* initialize 8253 clock */
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outb(TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT);
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/* Correct rounding will buy us a better precision in timekeeping */
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outb(IO_TIMER1, tval % 256);
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outb(IO_TIMER1, tval / 256);
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rtclock_tval = tval;
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check_clock_bug();
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}
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/*
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* microtime() makes use of the following globals. Note that isa_timer_tick
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* may be redundant to the `tick' variable, but is kept here for stability.
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* isa_timer_count is the countdown count for the timer. timer_msb_table[]
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* and timer_lsb_table[] are used to compute the microsecond increment
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* for time.tv_usec in the follow fashion:
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*
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* time.tv_usec += isa_timer_msb_table[cnt_msb] - isa_timer_lsb_table[cnt_lsb];
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*/
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#define ISA_TIMER_MSB_TABLE_SIZE 128
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u_long isa_timer_tick; /* the number of microseconds in a tick */
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u_short isa_timer_count; /* the countdown count for the timer */
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u_short isa_timer_msb_table[ISA_TIMER_MSB_TABLE_SIZE]; /* timer->usec MSB */
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u_short isa_timer_lsb_table[256]; /* timer->usec conversion for LSB */
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void
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startrtclock()
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{
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int s;
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u_long tval;
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u_long t, msb, lsb, quotient, remainder;
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if (!rtclock_tval)
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initrtclock();
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/*
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* Compute timer_tick from hz. We truncate this value (i.e.
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* round down) to minimize the possibility of a backward clock
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* step if hz is not a nice number.
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*/
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isa_timer_tick = 1000000 / (u_long) hz;
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/*
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* We can't stand any number with an MSB larger than
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* TIMER_MSB_TABLE_SIZE will accomodate.
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*/
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tval = rtclock_tval;
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if ((tval / 256) >= ISA_TIMER_MSB_TABLE_SIZE
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|| TIMER_FREQ > (8*1024*1024)) {
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panic("startrtclock: TIMER_FREQ/HZ unsupportable");
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}
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isa_timer_count = (u_short) tval;
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/*
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* Now compute the translation tables from timer ticks to
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* microseconds. We go to some length to ensure all values
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* are rounded-to-nearest (i.e. +-0.5 of the exact values)
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* as this will ensure the computation
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*
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* isa_timer_msb_table[msb] - isa_timer_lsb_table[lsb]
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*
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* will produce a result which is +-1 usec away from the
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* correctly rounded conversion (in fact, it'll be exact about
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* 75% of the time, 1 too large 12.5% of the time, and 1 too
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* small 12.5% of the time).
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*/
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for (s = 0; s < 256; s++) {
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/* LSB table is easy, just divide and round */
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t = ((u_long) s * 1000000 * 2) / TIMER_FREQ;
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isa_timer_lsb_table[s] = (u_short) ((t / 2) + (t & 0x1));
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/* MSB table is zero unless the MSB is <= isa_timer_count */
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if (s < ISA_TIMER_MSB_TABLE_SIZE) {
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msb = ((u_long) s) * 256;
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if (msb > tval) {
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isa_timer_msb_table[s] = 0;
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} else {
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/*
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* Harder computation here, since multiplying
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* the value by 1000000 can overflow a long.
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* To avoid 64-bit computations we divide
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* the high order byte and the low order
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* byte of the numerator separately, adding
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* the remainder of the first computation
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* into the second. The constraint on
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* TIMER_FREQ above should prevent overflow
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* here.
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*/
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msb = tval - msb;
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lsb = msb % 256;
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msb = (msb / 256) * 1000000;
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quotient = msb / TIMER_FREQ;
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remainder = msb % TIMER_FREQ;
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t = ((remainder * 256 * 2)
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+ (lsb * 1000000 * 2)) / TIMER_FREQ;
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isa_timer_msb_table[s] = (u_short)((t / 2)
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+ (t & 0x1) + (quotient * 256));
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}
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}
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}
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/* Check diagnostic status */
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if ((s = mc146818_read(NULL, NVRAM_DIAG)) != 0) { /* XXX softc */
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char bits[128];
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printf("RTC BIOS diagnostic error %s\n",
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bitmask_snprintf(s, NVRAM_DIAG_BITS, bits, sizeof(bits)));
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}
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}
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int
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clockintr(arg)
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void *arg;
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{
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struct clockframe *frame = arg; /* not strictly necessary */
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hardclock(frame);
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#if NMCA > 0
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if (MCA_system) {
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/* Reset PS/2 clock interrupt by asserting bit 7 of port 0x61 */
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outb(0x61, inb(0x61) | 0x80);
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}
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#endif
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return -1;
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}
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int
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gettick()
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{
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u_long ef;
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u_char lo, hi;
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if (clock_broken_latch)
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return (gettick_broken_latch());
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/* Don't want someone screwing with the counter while we're here. */
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ef = read_eflags();
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disable_intr();
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/* Select counter 0 and latch it. */
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outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
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lo = inb(TIMER_CNTR0);
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hi = inb(TIMER_CNTR0);
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write_eflags(ef);
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return ((hi << 8) | lo);
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}
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/*
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* Wait approximately `n' microseconds.
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* Relies on timer 1 counting down from (TIMER_FREQ / hz) at TIMER_FREQ Hz.
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* Note: timer had better have been programmed before this is first used!
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* (Note that we use `rate generator' mode, which counts at 1:1; `square
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* wave' mode counts at 2:1).
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* Don't rely on this being particularly accurate.
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*/
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void
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delay(n)
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int n;
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{
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int tick, otick;
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static const int delaytab[26] = {
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0, 2, 3, 4, 5, 6, 7, 9, 10, 11,
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12, 13, 15, 16, 17, 18, 19, 21, 22, 23,
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24, 25, 27, 28, 29, 30,
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};
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/* allow DELAY() to be used before startrtclock() */
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if (!rtclock_tval)
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initrtclock();
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/*
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* Read the counter first, so that the rest of the setup overhead is
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* counted.
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*/
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otick = gettick();
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if (n <= 25)
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n = delaytab[n];
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else {
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#ifdef __GNUC__
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/*
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* Calculate ((n * TIMER_FREQ) / 1e6) using explicit assembler
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* code so we can take advantage of the intermediate 64-bit
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* quantity to prevent loss of significance.
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*/
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int m;
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__asm __volatile("mul %3"
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: "=a" (n), "=d" (m)
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: "0" (n), "r" (TIMER_FREQ));
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__asm __volatile("div %4"
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: "=a" (n), "=d" (m)
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: "0" (n), "1" (m), "r" (1000000));
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#else
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/*
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* Calculate ((n * TIMER_FREQ) / 1e6) without using floating
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* point and without any avoidable overflows.
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*/
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int sec = n / 1000000,
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usec = n % 1000000;
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n = sec * TIMER_FREQ +
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usec * (TIMER_FREQ / 1000000) +
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usec * ((TIMER_FREQ % 1000000) / 1000) / 1000 +
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usec * (TIMER_FREQ % 1000) / 1000000;
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#endif
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}
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while (n > 0) {
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#ifdef CLOCK_PARANOIA
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int delta;
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tick = gettick();
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if (tick > otick)
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delta = rtclock_tval - (tick - otick);
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else
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delta = otick - tick;
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if (delta < 0 || delta >= rtclock_tval / 2) {
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DPRINTF(("delay: ignore ticks %.4x-%.4x",
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otick, tick));
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if (clock_broken_latch) {
|
|
DPRINTF((" (%.4x %.4x %.4x %.4x %.4x %.4x)\n",
|
|
ticks[0], ticks[1], ticks[2],
|
|
ticks[3], ticks[4], ticks[5]));
|
|
} else {
|
|
DPRINTF(("\n"));
|
|
}
|
|
} else
|
|
n -= delta;
|
|
#else
|
|
tick = gettick();
|
|
if (tick > otick)
|
|
n -= rtclock_tval - (tick - otick);
|
|
else
|
|
n -= otick - tick;
|
|
#endif
|
|
otick = tick;
|
|
}
|
|
}
|
|
|
|
#if (NPCPPI > 0)
|
|
int
|
|
sysbeepmatch(parent, match, aux)
|
|
struct device *parent;
|
|
struct cfdata *match;
|
|
void *aux;
|
|
{
|
|
return (!ppi_attached);
|
|
}
|
|
|
|
void
|
|
sysbeepattach(parent, self, aux)
|
|
struct device *parent, *self;
|
|
void *aux;
|
|
{
|
|
printf("\n");
|
|
|
|
ppicookie = ((struct pcppi_attach_args *)aux)->pa_cookie;
|
|
ppi_attached = 1;
|
|
}
|
|
#endif
|
|
|
|
void
|
|
sysbeep(pitch, period)
|
|
int pitch, period;
|
|
{
|
|
#if (NPCPPI > 0)
|
|
if (ppi_attached)
|
|
pcppi_bell(ppicookie, pitch, period, 0);
|
|
#endif
|
|
}
|
|
|
|
void
|
|
cpu_initclocks()
|
|
{
|
|
|
|
/*
|
|
* XXX If you're doing strange things with multiple clocks, you might
|
|
* want to keep track of clock handlers.
|
|
*/
|
|
(void)isa_intr_establish(NULL, 0, IST_PULSE, IPL_CLOCK, clockintr, 0);
|
|
}
|
|
|
|
void
|
|
rtcinit()
|
|
{
|
|
static int first_rtcopen_ever = 1;
|
|
|
|
if (!first_rtcopen_ever)
|
|
return;
|
|
first_rtcopen_ever = 0;
|
|
|
|
mc146818_write(NULL, MC_REGA, /* XXX softc */
|
|
MC_BASE_32_KHz | MC_RATE_1024_Hz);
|
|
mc146818_write(NULL, MC_REGB, MC_REGB_24HR); /* XXX softc */
|
|
}
|
|
|
|
int
|
|
rtcget(regs)
|
|
mc_todregs *regs;
|
|
{
|
|
|
|
rtcinit();
|
|
if ((mc146818_read(NULL, MC_REGD) & MC_REGD_VRT) == 0) /* XXX softc */
|
|
return (-1);
|
|
MC146818_GETTOD(NULL, regs); /* XXX softc */
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
rtcput(regs)
|
|
mc_todregs *regs;
|
|
{
|
|
|
|
rtcinit();
|
|
MC146818_PUTTOD(NULL, regs); /* XXX softc */
|
|
}
|
|
|
|
int
|
|
bcdtobin(n)
|
|
int n;
|
|
{
|
|
|
|
return (((n >> 4) & 0x0f) * 10 + (n & 0x0f));
|
|
}
|
|
|
|
int
|
|
bintobcd(n)
|
|
int n;
|
|
{
|
|
|
|
return ((u_char)(((n / 10) << 4) & 0xf0) | ((n % 10) & 0x0f));
|
|
}
|
|
|
|
static int timeset;
|
|
|
|
/*
|
|
* check whether the CMOS layout is "standard"-like (ie, not PS/2-like),
|
|
* to be called at splclock()
|
|
*/
|
|
static int cmoscheck __P((void));
|
|
static int
|
|
cmoscheck()
|
|
{
|
|
int i;
|
|
unsigned short cksum = 0;
|
|
|
|
for (i = 0x10; i <= 0x2d; i++)
|
|
cksum += mc146818_read(NULL, i); /* XXX softc */
|
|
|
|
return (cksum == (mc146818_read(NULL, 0x2e) << 8)
|
|
+ mc146818_read(NULL, 0x2f));
|
|
}
|
|
|
|
#if NMCA > 0
|
|
/*
|
|
* Check whether the CMOS layout is PS/2 like, to be called at splclock().
|
|
*/
|
|
static int cmoscheckps2 __P((void));
|
|
static int
|
|
cmoscheckps2()
|
|
{
|
|
#if 0
|
|
/* Disabled until I find out the CRC checksum algorithm IBM uses */
|
|
int i;
|
|
unsigned short cksum = 0;
|
|
|
|
for (i = 0x10; i <= 0x31; i++)
|
|
cksum += mc146818_read(NULL, i); /* XXX softc */
|
|
|
|
return (cksum == (mc146818_read(NULL, 0x32) << 8)
|
|
+ mc146818_read(NULL, 0x33));
|
|
#else
|
|
/* Check 'incorrect checksum' bit of IBM PS/2 Diagnostic Status Byte */
|
|
return ((mc146818_read(NULL, NVRAM_DIAG) & (1<<6)) == 0);
|
|
#endif
|
|
}
|
|
#endif /* NMCA > 0 */
|
|
|
|
/*
|
|
* patchable to control century byte handling:
|
|
* 1: always update
|
|
* -1: never touch
|
|
* 0: try to figure out itself
|
|
*/
|
|
int rtc_update_century = 0;
|
|
|
|
/*
|
|
* Expand a two-digit year as read from the clock chip
|
|
* into full width.
|
|
* Being here, deal with the CMOS century byte.
|
|
*/
|
|
static int centb = NVRAM_CENTURY;
|
|
static int clock_expandyear __P((int));
|
|
static int
|
|
clock_expandyear(clockyear)
|
|
int clockyear;
|
|
{
|
|
int s, clockcentury, cmoscentury;
|
|
|
|
clockcentury = (clockyear < 70) ? 20 : 19;
|
|
clockyear += 100 * clockcentury;
|
|
|
|
if (rtc_update_century < 0)
|
|
return (clockyear);
|
|
|
|
s = splclock();
|
|
if (cmoscheck())
|
|
cmoscentury = mc146818_read(NULL, NVRAM_CENTURY);
|
|
#if NMCA > 0
|
|
else if (MCA_system && cmoscheckps2())
|
|
cmoscentury = mc146818_read(NULL, (centb = 0x37));
|
|
#endif
|
|
else
|
|
cmoscentury = 0;
|
|
splx(s);
|
|
if (!cmoscentury) {
|
|
#ifdef DIAGNOSTIC
|
|
printf("clock: unknown CMOS layout\n");
|
|
#endif
|
|
return (clockyear);
|
|
}
|
|
cmoscentury = bcdtobin(cmoscentury);
|
|
|
|
if (cmoscentury != clockcentury) {
|
|
/* XXX note: saying "century is 20" might confuse the naive. */
|
|
printf("WARNING: NVRAM century is %d but RTC year is %d\n",
|
|
cmoscentury, clockyear);
|
|
|
|
/* Kludge to roll over century. */
|
|
if ((rtc_update_century > 0) ||
|
|
((cmoscentury == 19) && (clockcentury == 20) &&
|
|
(clockyear == 2000))) {
|
|
printf("WARNING: Setting NVRAM century to %d\n",
|
|
clockcentury);
|
|
s = splclock();
|
|
mc146818_write(NULL, centb, bintobcd(clockcentury));
|
|
splx(s);
|
|
}
|
|
} else if (cmoscentury == 19 && rtc_update_century == 0)
|
|
rtc_update_century = 1; /* will update later in resettodr() */
|
|
|
|
return (clockyear);
|
|
}
|
|
|
|
/*
|
|
* Initialize the time of day register, based on the time base which is, e.g.
|
|
* from a filesystem.
|
|
*/
|
|
void
|
|
inittodr(base)
|
|
time_t base;
|
|
{
|
|
mc_todregs rtclk;
|
|
struct clock_ymdhms dt;
|
|
int s;
|
|
|
|
/*
|
|
* We mostly ignore the suggested time (which comes from the
|
|
* file system) and go for the RTC clock time stored in the
|
|
* CMOS RAM. If the time can't be obtained from the CMOS, or
|
|
* if the time obtained from the CMOS is 5 or more years less
|
|
* than the suggested time, we used the suggested time. (In
|
|
* the latter case, it's likely that the CMOS battery has
|
|
* died.)
|
|
*/
|
|
|
|
/*
|
|
* XXX Traditionally, the dates in this code snippet get
|
|
* updated every few years. It would be neater if they could
|
|
* somehow be automatically set when the kernel was built.
|
|
*/
|
|
if (base && base < 30*SECYR) { /* if before 2000, something's odd. */
|
|
printf("WARNING: preposterous time in file system\n");
|
|
/* Since the fs time is silly, set the base time to 2002 */
|
|
base = 32*SECYR;
|
|
}
|
|
|
|
s = splclock();
|
|
if (rtcget(&rtclk)) {
|
|
splx(s);
|
|
printf("WARNING: invalid time in clock chip\n");
|
|
goto fstime;
|
|
}
|
|
splx(s);
|
|
#ifdef DEBUG_CLOCK
|
|
printf("readclock: %x/%x/%x %x:%x:%x\n", rtclk[MC_YEAR],
|
|
rtclk[MC_MONTH], rtclk[MC_DOM], rtclk[MC_HOUR], rtclk[MC_MIN],
|
|
rtclk[MC_SEC]);
|
|
#endif
|
|
|
|
dt.dt_sec = bcdtobin(rtclk[MC_SEC]);
|
|
dt.dt_min = bcdtobin(rtclk[MC_MIN]);
|
|
dt.dt_hour = bcdtobin(rtclk[MC_HOUR]);
|
|
dt.dt_day = bcdtobin(rtclk[MC_DOM]);
|
|
dt.dt_mon = bcdtobin(rtclk[MC_MONTH]);
|
|
dt.dt_year = clock_expandyear(bcdtobin(rtclk[MC_YEAR]));
|
|
|
|
/*
|
|
* If time_t is 32 bits, then the "End of Time" is
|
|
* Mon Jan 18 22:14:07 2038 (US/Eastern)
|
|
* This code copes with RTC's past the end of time if time_t
|
|
* is an int32 or less. Needed because sometimes RTCs screw
|
|
* up or are badly set, and that would cause the time to go
|
|
* negative in the calculation below, which causes Very Bad
|
|
* Mojo. This at least lets the user boot and fix the problem.
|
|
* Note the code is self eliminating once time_t goes to 64 bits.
|
|
*/
|
|
if (sizeof(time_t) <= sizeof(int32_t)) {
|
|
if (dt.dt_year >= 2038) {
|
|
printf("WARNING: RTC time at or beyond 2038.\n");
|
|
dt.dt_year = 2037;
|
|
printf("WARNING: year set back to 2037.\n");
|
|
printf("WARNING: CHECK AND RESET THE DATE!\n");
|
|
}
|
|
}
|
|
|
|
time.tv_sec = clock_ymdhms_to_secs(&dt) + rtc_offset * 60;
|
|
#ifdef DEBUG_CLOCK
|
|
printf("readclock: %ld (%ld)\n", time.tv_sec, base);
|
|
#endif
|
|
|
|
if (base != 0 && base < time.tv_sec - 5*SECYR)
|
|
printf("WARNING: file system time much less than clock time\n");
|
|
else if (base > time.tv_sec + 5*SECYR) {
|
|
printf("WARNING: clock time much less than file system time\n");
|
|
printf("WARNING: using file system time\n");
|
|
goto fstime;
|
|
}
|
|
|
|
timeset = 1;
|
|
return;
|
|
|
|
fstime:
|
|
timeset = 1;
|
|
time.tv_sec = base;
|
|
printf("WARNING: CHECK AND RESET THE DATE!\n");
|
|
}
|
|
|
|
/*
|
|
* Reset the clock.
|
|
*/
|
|
void
|
|
resettodr()
|
|
{
|
|
mc_todregs rtclk;
|
|
struct clock_ymdhms dt;
|
|
int century;
|
|
int s;
|
|
|
|
/*
|
|
* We might have been called by boot() due to a crash early
|
|
* on. Don't reset the clock chip in this case.
|
|
*/
|
|
if (!timeset)
|
|
return;
|
|
|
|
s = splclock();
|
|
if (rtcget(&rtclk))
|
|
memset(&rtclk, 0, sizeof(rtclk));
|
|
splx(s);
|
|
|
|
clock_secs_to_ymdhms(time.tv_sec - rtc_offset * 60, &dt);
|
|
|
|
rtclk[MC_SEC] = bintobcd(dt.dt_sec);
|
|
rtclk[MC_MIN] = bintobcd(dt.dt_min);
|
|
rtclk[MC_HOUR] = bintobcd(dt.dt_hour);
|
|
rtclk[MC_DOW] = dt.dt_wday;
|
|
rtclk[MC_YEAR] = bintobcd(dt.dt_year % 100);
|
|
rtclk[MC_MONTH] = bintobcd(dt.dt_mon);
|
|
rtclk[MC_DOM] = bintobcd(dt.dt_day);
|
|
|
|
#ifdef DEBUG_CLOCK
|
|
printf("setclock: %x/%x/%x %x:%x:%x\n", rtclk[MC_YEAR], rtclk[MC_MONTH],
|
|
rtclk[MC_DOM], rtclk[MC_HOUR], rtclk[MC_MIN], rtclk[MC_SEC]);
|
|
#endif
|
|
s = splclock();
|
|
rtcput(&rtclk);
|
|
if (rtc_update_century > 0) {
|
|
century = bintobcd(dt.dt_year / 100);
|
|
mc146818_write(NULL, centb, century); /* XXX softc */
|
|
}
|
|
splx(s);
|
|
}
|
|
|
|
void
|
|
setstatclockrate(arg)
|
|
int arg;
|
|
{
|
|
}
|