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clock.c revision 1.2 
      1 /* $NetBSD: clock.c,v 1.2 2008/01/07 17:27:12 joerg Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2007 Jared D. McNeill <jmcneill (at) invisible.ca>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *        This product includes software developed by Jared D. McNeill.
     18  * 4. Neither the name of The NetBSD Foundation nor the names of its
     19  *    contributors may be used to endorse or promote products derived
     20  *    from this software without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     32  * POSSIBILITY OF SUCH DAMAGE.
     33  */
     34 
     35 #include <sys/cdefs.h>
     36 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.2 2008/01/07 17:27:12 joerg Exp $");
     37 
     38 #include <sys/param.h>
     39 #include <sys/proc.h>
     40 #include <sys/user.h>
     41 #include <sys/systm.h>
     42 #include <sys/device.h>
     43 #include <sys/timetc.h>
     44 
     45 #include <machine/mainbus.h>
     46 
     47 static int	clock_match(device_t, cfdata_t, void *);
     48 static void	clock_attach(device_t, device_t, void *);
     49 
     50 static void 	clock_intr(int);
     51 static u_int	clock_getcounter(struct timecounter *);
     52 
     53 typedef struct clock_softc {
     54 	device_t	sc_dev;
     55 } clock_softc_t;
     56 
     57 extern int	setitimer(int, const struct itimerval *, struct itimerval *);
     58 
     59 static struct timecounter clock_timecounter = {
     60 	clock_getcounter,	/* get_timecount */
     61 	0,			/* no poll_pps */
     62 	~0u,			/* counter_mask */
     63 	1000000,		/* frequency */
     64 	"gettimeofday",		/* name */
     65 	100,			/* quality */
     66 	NULL,			/* prev */
     67 	NULL,			/* next */
     68 };
     69 
     70 CFATTACH_DECL_NEW(clock, sizeof(clock_softc_t),
     71     clock_match, clock_attach, NULL, NULL);
     72 
     73 static int
     74 clock_match(device_t parent, cfdata_t match, void *opaque)
     75 {
     76 	struct thunkbus_attach_args *taa = opaque;
     77 
     78 	if (taa->taa_type != THUNKBUS_TYPE_CLOCK)
     79 		return 0;
     80 
     81 	return 1;
     82 }
     83 
     84 static void
     85 clock_attach(device_t parent, device_t self, void *opaque)
     86 {
     87 	clock_softc_t *sc = device_private(self);
     88 	struct itimerval itimer;
     89 
     90 	aprint_naive("\n");
     91 	aprint_normal("\n");
     92 
     93 	sc->sc_dev = self;
     94 
     95 	(void)signal(SIGALRM, clock_intr);
     96 
     97 	itimer.it_interval.tv_sec = 0;
     98 	itimer.it_interval.tv_usec = 10000;
     99 	itimer.it_value = itimer.it_interval;
    100 	(void)setitimer(ITIMER_REAL, &itimer, NULL);
    101 
    102 	tc_init(&clock_timecounter);
    103 }
    104 
    105 static void
    106 clock_intr(int notused)
    107 {
    108 	extern int usermode_x;
    109 	struct clockframe cf;
    110 
    111 #if notyet
    112 	/* XXXJDM */
    113 	if (usermode_x > IPL_SOFTCLOCK)
    114 		return;
    115 #endif
    116 
    117 	hardclock(&cf);
    118 }
    119 
    120 static u_int
    121 clock_getcounter(struct timecounter *tc)
    122 {
    123 	extern int gettimeofday(struct timeval *, void *);
    124 	struct timeval tv;
    125 
    126 	gettimeofday(&tv, NULL);
    127 	return tv.tv_sec * 1000000 + tv.tv_usec;
    128 }
    129