sys/arch/usermode/dev/clock.c

   1 /* $NetBSD: clock.c,v 1.3 2009/10/21 16:06:59 snj Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2007 Jared D. McNeill <jmcneill@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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26  * POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.3 2009/10/21 16:06:59 snj Exp $");
  31
  32 #include <sys/param.h>
  33 #include <sys/proc.h>
  34 #include <sys/systm.h>
  35 #include <sys/device.h>
  36 #include <sys/timetc.h>
  37
  38 #include <machine/mainbus.h>
  39
  40 static int      clock_match(device_t, cfdata_t, void *);
  41 static void     clock_attach(device_t, device_t, void *);
  42
  43 static void     clock_intr(int);
  44 static u_int    clock_getcounter(struct timecounter *);
  45
  46 typedef struct clock_softc {
  47         device_t        sc_dev;
  48 } clock_softc_t;
  49
  50 extern int      setitimer(int, const struct itimerval *, struct itimerval *);
  51
  52 static struct timecounter clock_timecounter = {
  53         clock_getcounter,       /* get_timecount */
  54         0,                      /* no poll_pps */
  55         ~0u,                    /* counter_mask */
  56         1000000,                /* frequency */
  57         "gettimeofday",         /* name */
  58         100,                    /* quality */
  59         NULL,                   /* prev */
  60         NULL,                   /* next */
  61 };
  62
  63 CFATTACH_DECL_NEW(clock, sizeof(clock_softc_t),
  64     clock_match, clock_attach, NULL, NULL);
  65
  66 static int
  67 clock_match(device_t parent, cfdata_t match, void *opaque)
  68 {
  69         struct thunkbus_attach_args *taa = opaque;
  70
  71         if (taa->taa_type != THUNKBUS_TYPE_CLOCK)
  72                 return 0;
  73
  74         return 1;
  75 }
  76
  77 static void
  78 clock_attach(device_t parent, device_t self, void *opaque)
  79 {
  80         clock_softc_t *sc = device_private(self);
  81         struct itimerval itimer;
  82
  83         aprint_naive("\n");
  84         aprint_normal("\n");
  85
  86         sc->sc_dev = self;
  87
  88         (void)signal(SIGALRM, clock_intr);
  89
  90         itimer.it_interval.tv_sec = 0;
  91         itimer.it_interval.tv_usec = 10000;
  92         itimer.it_value = itimer.it_interval;
  93         (void)setitimer(ITIMER_REAL, &itimer, NULL);
  94
  95         tc_init(&clock_timecounter);
  96 }
  97
  98 static void
  99 clock_intr(int notused)
 100 {
 101         extern int usermode_x;
 102         struct clockframe cf;
 103
 104 #if notyet
 105         /* XXXJDM */
 106         if (usermode_x > IPL_SOFTCLOCK)
 107                 return;
 108 #endif
 109
 110         hardclock(&cf);
 111 }
 112
 113 static u_int
 114 clock_getcounter(struct timecounter *tc)
 115 {
 116         extern int gettimeofday(struct timeval *, void *);
 117         struct timeval tv;
 118
 119         gettimeofday(&tv, NULL);
 120         return tv.tv_sec * 1000000 + tv.tv_usec;
 121 }