xref: /netbsd-src/sys/arch/usermode/dev/clock.c (revision bd1f9e680783606ba327ccadf6002a15ffbdf514)
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/user.h>
35 #include <sys/systm.h>
36 #include <sys/device.h>
37 #include <sys/timetc.h>
38 
39 #include <machine/mainbus.h>
40 
41 static int	clock_match(device_t, cfdata_t, void *);
42 static void	clock_attach(device_t, device_t, void *);
43 
44 static void 	clock_intr(int);
45 static u_int	clock_getcounter(struct timecounter *);
46 
47 typedef struct clock_softc {
48 	device_t	sc_dev;
49 } clock_softc_t;
50 
51 extern int	setitimer(int, const struct itimerval *, struct itimerval *);
52 
53 static struct timecounter clock_timecounter = {
54 	clock_getcounter,	/* get_timecount */
55 	0,			/* no poll_pps */
56 	~0u,			/* counter_mask */
57 	1000000,		/* frequency */
58 	"gettimeofday",		/* name */
59 	100,			/* quality */
60 	NULL,			/* prev */
61 	NULL,			/* next */
62 };
63 
64 CFATTACH_DECL_NEW(clock, sizeof(clock_softc_t),
65     clock_match, clock_attach, NULL, NULL);
66 
67 static int
68 clock_match(device_t parent, cfdata_t match, void *opaque)
69 {
70 	struct thunkbus_attach_args *taa = opaque;
71 
72 	if (taa->taa_type != THUNKBUS_TYPE_CLOCK)
73 		return 0;
74 
75 	return 1;
76 }
77 
78 static void
79 clock_attach(device_t parent, device_t self, void *opaque)
80 {
81 	clock_softc_t *sc = device_private(self);
82 	struct itimerval itimer;
83 
84 	aprint_naive("\n");
85 	aprint_normal("\n");
86 
87 	sc->sc_dev = self;
88 
89 	(void)signal(SIGALRM, clock_intr);
90 
91 	itimer.it_interval.tv_sec = 0;
92 	itimer.it_interval.tv_usec = 10000;
93 	itimer.it_value = itimer.it_interval;
94 	(void)setitimer(ITIMER_REAL, &itimer, NULL);
95 
96 	tc_init(&clock_timecounter);
97 }
98 
99 static void
100 clock_intr(int notused)
101 {
102 	extern int usermode_x;
103 	struct clockframe cf;
104 
105 #if notyet
106 	/* XXXJDM */
107 	if (usermode_x > IPL_SOFTCLOCK)
108 		return;
109 #endif
110 
111 	hardclock(&cf);
112 }
113 
114 static u_int
115 clock_getcounter(struct timecounter *tc)
116 {
117 	extern int gettimeofday(struct timeval *, void *);
118 	struct timeval tv;
119 
120 	gettimeofday(&tv, NULL);
121 	return tv.tv_sec * 1000000 + tv.tv_usec;
122 }
123