xref: /netbsd-src/sys/arch/sparc/sparc/timervar.h (revision 5eadbc3ac174cf47c88f8d339df4a13c7a9c5e96)
1 /*	$NetBSD: timervar.h,v 1.13 2021/01/24 07:36:54 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * All advertising materials mentioning features or use of this software
12  * must display the following acknowledgement:
13  *	This product includes software developed by the University of
14  *	California, Lawrence Berkeley Laboratory.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #include "opt_sparc_arch.h"
42 
43 #if defined(SUN4) || defined(SUN4C)
44 int	clockintr_4(void *);
45 int	statintr_4(void *);
46 void	timer_init_4(void);
47 
48 void	timerattach_obio_4(device_t, device_t, void *);
49 void	timerattach_mainbus_4c(device_t, device_t, void *);
50 #endif /* SUN4 || SUN4C */
51 
52 #if defined(SUN4M)
53 int	clockintr_4m(void *);
54 int	statintr_4m(void *);
55 void	timer_init_4m(void);
56 
57 void	timerattach_obio_4m(device_t, device_t, void *);
58 #endif /* SUN4M */
59 
60 /* Imported from clock.c: */
61 extern int statvar, statmin, statint;
62 extern int timerblurb;
63 extern void (*timer_init)(void);
64 extern int (*eeprom_nvram_wenable)(int);
65 extern int oldclk;
66 extern int timerblurb;
67 void tickle_tc(void);
68 
69 /* Common timer attach routine in timer.c: */
70 void	timerattach(volatile int *, volatile int *);
71 extern void	*sched_cookie;		/* for schedclock() interrupts */
72 
73 static inline u_long __attribute__((__unused__))
new_interval(void)74 new_interval(void)
75 {
76 	u_long newint, r, var;
77 
78 	/*
79 	 * Compute new randomized interval.  The intervals are uniformly
80 	 * distributed on [statint - statvar / 2, statint + statvar / 2],
81 	 * and therefore have mean statint, giving a stathz frequency clock.
82 	 */
83 	var = statvar;
84 	do {
85 		r = random() & (var - 1);
86 	} while (r == 0);
87 	newint = statmin + r;
88 	return (newint);
89 }
90