595 lines
17 KiB
C
595 lines
17 KiB
C
/* $NetBSD: clock.c,v 1.13 2006/09/13 07:13:03 gdamore Exp $ */
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/*
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* Copyright 1997
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* Digital Equipment Corporation. All rights reserved.
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*
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* This software is furnished under license and may be used and
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* copied only in accordance with the following terms and conditions.
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* Subject to these conditions, you may download, copy, install,
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* use, modify and distribute this software in source and/or binary
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* form. No title or ownership is transferred hereby.
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*
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* 1) Any source code used, modified or distributed must reproduce
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* and retain this copyright notice and list of conditions as
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* they appear in the source file.
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*
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* 2) No right is granted to use any trade name, trademark, or logo of
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* Digital Equipment Corporation. Neither the "Digital Equipment
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* Corporation" name nor any trademark or logo of Digital Equipment
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* Corporation may be used to endorse or promote products derived
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* from this software without the prior written permission of
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* Digital Equipment Corporation.
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*
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* 3) This software is provided "AS-IS" and any express or implied
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* warranties, including but not limited to, any implied warranties
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* of merchantability, fitness for a particular purpose, or
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* non-infringement are disclaimed. In no event shall DIGITAL be
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* liable for any damages whatsoever, and in particular, DIGITAL
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* shall not be liable for special, indirect, consequential, or
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* incidental damages or damages for lost profits, loss of
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* revenue or loss of use, whether such damages arise in contract,
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* negligence, tort, under statute, in equity, at law or otherwise,
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* even if advised of the possibility of such damage.
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*/
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/*-
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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. 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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* Copyright (c) 1993, 1994 Charles M. Hannum.
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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 1.13 2006/09/13 07:13:03 gdamore Exp $");
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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/timetc.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 <arm/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 <dev/ic/i8253reg.h>
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#include <shark/isa/nvram.h>
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#include <shark/isa/spkrreg.h>
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#include <shark/shark/hat.h>
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void sysbeepstop(void *);
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void sysbeep(int, int);
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void rtcinit(void);
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int timer_hz_to_count(int);
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static void findcpuspeed(void);
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static void delayloop(int);
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static int clockintr(void *);
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static int gettick(void);
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static void tc_init_i8253(void);
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void startrtclock(void);
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inline unsigned mc146818_read(void *, unsigned);
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inline void mc146818_write(void *, unsigned, unsigned);
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inline unsigned
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mc146818_read(void *sc, unsigned 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(void *sc, unsigned reg, unsigned 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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unsigned int count1024usec; /* calibrated loop variable (1024 microseconds) */
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/* number of timer ticks in a Musec = 2^20 usecs */
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#define TIMER_MUSECFREQ\
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(((((((TIMER_FREQ) * 1024) + 999) / 1000) * 1024) + 999) / 1000)
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#define TIMER_MUSECDIV(x) ((TIMER_MUSECFREQ+(x)/2)/(x))
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/*
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* microtime() makes use of the following globals.
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* timer_msb_table[] and timer_lsb_table[] are used to compute the
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* microsecond increment.
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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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u_short isa_timer_lsb_table[256]; /* timer->usec conversion for LSB */
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/* 64 bit counts from timer 0 */
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struct count64 {
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unsigned lo; /* low 32 bits */
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unsigned hi; /* high 32 bits */
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};
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#define TIMER0_ROLLOVER 0xFFFF /* maximum rollover for 8254 counter */
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struct count64 timer0count;
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struct count64 timer0_at_last_clockintr;
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unsigned timer0last;
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/*#define TESTHAT*/
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#ifdef TESTHAT
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#define HATSTACKSIZE 1024
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#define HATHZ 50000
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#define HATHZ2 10000
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unsigned char hatStack[HATSTACKSIZE];
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unsigned testHatOn = 0;
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unsigned nHats = 0;
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unsigned nHatWedges = 0;
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unsigned fiqReason = 0;
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unsigned hatCount = 0;
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unsigned hatCount2 = 0;
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void hatTest(int testReason)
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{
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fiqReason |= testReason;
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nHats++;
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}
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void hatWedge(int nFIQs)
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{
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printf("Unwedging the HAT. fiqs_happened = %d\n", nFIQs);
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nHatWedges++;
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}
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#endif
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void
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startrtclock(void)
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{
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findcpuspeed(); /* use the clock (while it's free) to
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find the CPU speed */
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timer0count.lo = 0;
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timer0count.hi = 0;
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timer0_at_last_clockintr.lo = 0;
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timer0_at_last_clockintr.hi = 0;
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timer0last = 0;
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/* initialize 8253 clock */
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outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT);
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outb(IO_TIMER1 + TIMER_CNTR0, TIMER0_ROLLOVER % 256);
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outb(IO_TIMER1 + TIMER_CNTR0, TIMER0_ROLLOVER / 256);
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#ifdef TESTHAT
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hatCount = timer_hz_to_count(HATHZ);
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hatCount2 = timer_hz_to_count(HATHZ2);
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printf("HAT test on @ %d Hz = %d ticks\n", HATHZ, hatCount);
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#endif
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}
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int
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timer_hz_to_count(int timer_hz)
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{
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u_long tval;
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tval = (TIMER_FREQ * 2) / (u_long) timer_hz;
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tval = (tval / 2) + (tval & 0x1);
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return (int)tval;
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}
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void gettimer0count(struct count64 *);
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/* must be called at SPL_CLOCK or higher */
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void gettimer0count(struct count64 *pcount)
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{
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unsigned current, ticks, oldlo;
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/*
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* Latch the current value of the timer and then read it.
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* This guarantees an atomic reading of the time.
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*/
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current = gettick();
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if (timer0last >= current)
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ticks = timer0last - current;
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else
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ticks = timer0last + (TIMER0_ROLLOVER - current);
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timer0last = current;
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oldlo = timer0count.lo;
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if (oldlo > (timer0count.lo = oldlo + ticks)) /* carry? */
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timer0count.hi++;
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*pcount = timer0count;
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}
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static int
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clockintr(void *arg)
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{
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struct clockframe *frame = arg; /* not strictly necessary */
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extern void isa_specific_eoi(int irq);
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#ifdef TESTHAT
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static int ticks = 0;
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#endif
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static int hatUnwedgeCtr = 0;
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gettimer0count(&timer0_at_last_clockintr);
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mc146818_read(NULL, MC_REGC); /* clear the clock interrupt */
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/* check to see if the high-availability timer needs to be unwedged */
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if (++hatUnwedgeCtr >= (hz / HAT_MIN_FREQ)) {
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hatUnwedgeCtr = 0;
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hatUnwedge();
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}
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#ifdef TESTHAT
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++ticks;
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if (testHatOn && ((ticks & 0x3f) == 0)) {
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if (testHatOn == 1) {
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hatClkAdjust(hatCount2);
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testHatOn = 2;
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} else {
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testHatOn = 0;
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hatClkOff();
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printf("hat off status: %d %d %x\n", nHats,
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nHatWedges, fiqReason);
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}
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} else if (!testHatOn && (ticks & 0x1ff) == 0) {
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printf("hat on status: %d %d %x\n",
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nHats, nHatWedges, fiqReason);
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testHatOn = 1;
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nHats = 0;
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fiqReason = 0;
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hatClkOn(hatCount, hatTest, 0xfeedface,
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hatStack + HATSTACKSIZE - sizeof(unsigned),
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hatWedge);
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}
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#endif
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hardclock(frame);
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return(0);
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}
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static int
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gettick(void)
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{
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u_char lo, hi;
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u_int savedints;
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/* Don't want someone screwing with the counter while we're here. */
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savedints = disable_interrupts(I32_bit);
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/* Select counter 0 and latch it. */
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outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
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lo = inb(IO_TIMER1 + TIMER_CNTR0);
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hi = inb(IO_TIMER1 + TIMER_CNTR0);
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restore_interrupts(savedints);
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return ((hi << 8) | lo);
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}
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/* modifications from i386 to shark isa version:
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- removed hardcoded "n -=" values that approximated the time to
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calculate delay ticks
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- made the time to calculate delay ticks almost negligable. 4 multiplies
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= maximum of 12 cycles = 75ns on a slow SA-110, plus a bunch of shifts;
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as opposed to 4 multiplies plus a bunch of divides.
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- removed i386 assembly language hack
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- put code in findcpuspeed that works even if FIRST_GUESS is orders
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of magnitude low
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- put code in delay() to use delayloop() for short delays
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- microtime no longer in assembly language
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*/
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/*
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* Wait "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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*/
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void
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delay(unsigned n)
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{
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int ticks, otick;
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int nticks;
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if (n < 100) {
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/* it can take a long time (1 usec or longer) just for
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1 ISA read, so it's best not to use the timer for
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short delays */
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delayloop((n * count1024usec) >> 10);
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return;
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}
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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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/*
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* Calculate ((n * TIMER_FREQ) / 1e6) without using floating point and
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* without any avoidable overflows.
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*/
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{
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/* a Musec = 2^20 usec */
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int Musec = n >> 20,
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usec = n & ((1 << 20) - 1);
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nticks
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= (Musec * TIMER_MUSECFREQ) +
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(usec * (TIMER_MUSECFREQ >> 20)) +
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((usec * ((TIMER_MUSECFREQ & ((1 <<20) - 1)) >>10)) >>10) +
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((usec * (TIMER_MUSECFREQ & ((1 << 10) - 1))) >> 20);
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}
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while (nticks > 0) {
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ticks = gettick();
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if (ticks > otick)
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nticks -= TIMER0_ROLLOVER - (ticks - otick);
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else
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nticks -= otick - ticks;
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otick = ticks;
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}
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}
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void
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sysbeepstop(void *arg)
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{
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}
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void
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sysbeep(int pitch, int period)
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{
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}
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#define FIRST_GUESS 0x2000
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static void
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findcpuspeed(void)
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{
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int ticks;
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unsigned int guess = FIRST_GUESS;
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while (1) { /* loop until accurate enough */
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/* Put counter in count down mode */
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outb(IO_TIMER1 + TIMER_MODE,
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TIMER_SEL0 | TIMER_16BIT | TIMER_RATEGEN);
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outb(IO_TIMER1 + TIMER_CNTR0, 0xff);
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outb(IO_TIMER1 + TIMER_CNTR0, 0xff);
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delayloop(guess);
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/* Read the value left in the counter */
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/*
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* Formula for delaycount is:
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* (loopcount * timer clock speed) / (counter ticks * 1000)
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*/
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ticks = 0xFFFF - gettick();
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if (ticks == 0) ticks = 1; /* just in case */
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if (ticks < (TIMER_MUSECDIV(1024))) { /* not accurate enough */
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guess *= max(2, (TIMER_MUSECDIV(1024) / ticks));
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continue;
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}
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count1024usec = (guess * (TIMER_MUSECDIV(1024))) / ticks;
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return;
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}
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}
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static void
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delayloop(int counts)
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{
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while (counts--)
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__insn_barrier();
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}
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void
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cpu_initclocks(void)
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{
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unsigned hzval;
|
|
|
|
printf("clock: hz=%d stathz = %d profhz = %d\n", hz, stathz, profhz);
|
|
|
|
/* install RTC interrupt handler */
|
|
(void)isa_intr_establish(NULL, IRQ_RTC, IST_LEVEL, IPL_CLOCK,
|
|
clockintr, 0);
|
|
|
|
/* set up periodic interrupt @ hz
|
|
this is the subset of hz values in kern_clock.c that are
|
|
supported by the ISA RTC */
|
|
switch (hz) {
|
|
case 64:
|
|
hzval = MC_RATE_64_Hz;
|
|
break;
|
|
case 128:
|
|
hzval = MC_RATE_128_Hz;
|
|
break;
|
|
case 256:
|
|
hzval = MC_RATE_256_Hz;
|
|
break;
|
|
case 1024:
|
|
hzval = MC_RATE_1024_Hz;
|
|
break;
|
|
default:
|
|
panic("cannot configure hz = %d", hz);
|
|
}
|
|
|
|
rtcinit(); /* make sure basics are done by now */
|
|
|
|
/* blast values to set up clock interrupt */
|
|
mc146818_write(NULL, MC_REGA, MC_BASE_32_KHz | hzval);
|
|
/* enable periodic interrupt */
|
|
mc146818_write(NULL, MC_REGB,
|
|
mc146818_read(NULL, MC_REGB) | MC_REGB_PIE);
|
|
|
|
tc_init_i8253();
|
|
}
|
|
|
|
void
|
|
rtcinit(void)
|
|
{
|
|
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 */
|
|
}
|
|
|
|
void
|
|
setstatclockrate(int arg)
|
|
{
|
|
}
|
|
|
|
static uint32_t
|
|
i8253_get_timecount(struct timecounter *tc)
|
|
{
|
|
return (TIMER0_ROLLOVER - gettick());
|
|
}
|
|
|
|
void
|
|
tc_init_i8253(void)
|
|
{
|
|
static struct timecounter i8253_tc = {
|
|
.tc_get_timecount = i8253_get_timecount,
|
|
.tc_counter_mask = TIMER0_ROLLOVER,
|
|
.tc_frequency = TIMER_FREQ,
|
|
.tc_name = "i8253",
|
|
.tc_quality = 100
|
|
};
|
|
|
|
tc_init(&i8253_tc);
|
|
}
|
|
|
|
/* End of clock.c */
|