1/*	$NetBSD: clockvar.h,v 1.8 2008/04/28 20:23:54 martin Exp $	*/
2
3/*-
4 * Copyright (c) 1996, 2002 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _MVME_CLOCKVAR_H
33#define _MVME_CLOCKVAR_H
34
35#include <dev/clock_subr.h>
36
37/*
38 * Definitions exported to ASIC-specific clock attachment.
39 */
40
41extern	struct evcnt clock_profcnt;
42extern	struct evcnt clock_statcnt;
43
44extern	int clock_statvar;
45extern	int clock_statmin;
46
47struct clock_attach_args {
48	void			(*ca_initfunc)(void *, int, int);
49	void			*ca_arg;
50};
51
52void	clock_config(device_t, struct clock_attach_args *,
53			struct evcnt *);
54
55/*
56 * Macro to compute a new randomized interval.  The intervals are
57 * uniformly distributed on [statint - statvar / 2, statint + statvar / 2],
58 * and therefore have mean statint, giving a stathz frequency clock.
59 *
60 * This is gratuitously stolen from sparc/sparc/clock.c
61 */
62#define CLOCK_NEWINT(statvar, statmin)	({				\
63		u_long r, var = (statvar);				\
64		do { r = random() & (var - 1); } while (r == 0);	\
65		(statmin + r);						\
66	})
67
68/*
69 * Sun chose the year `68' as their base count, so that
70 * cl_year==0 means 1968.
71 */
72#define YEAR0   1968
73
74/*
75 * interrupt level for clock
76 */
77#define CLOCK_LEVEL 5
78
79#endif /* _MVME_CLOCKVAR_H */
80