xref: /netbsd-src/sys/arch/next68k/next68k/clock.c (revision 1d39c7845c7d63630dec9db1282715af056f440e)
1 /*	$NetBSD: clock.c,v 1.14 2023/02/03 23:13:01 tsutsui Exp $	*/
2 /*
3  * Copyright (c) 1998 Darrin B. Jewell
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.14 2023/02/03 23:13:01 tsutsui Exp $");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/tty.h>
34 #include <sys/device.h>
35 
36 #include <machine/psl.h>
37 #include <machine/bus.h>
38 #include <machine/cpu.h>
39 
40 #include <next68k/dev/clockreg.h>
41 #include <next68k/dev/intiovar.h>
42 
43 #include <next68k/next68k/rtc.h>
44 #include <next68k/next68k/isr.h>
45 
46 /* @@@ This is pretty bogus and will need fixing once
47  * things are working better.
48  * -- jewell@mit.edu
49  */
50 
51 int clock_intr(void *);
52 
53 int
clock_intr(void * arg)54 clock_intr(void *arg)
55 {
56 	volatile struct timer_reg *timer;
57 	int whilecount = 0;
58 
59 	if (!INTR_OCCURRED(NEXT_I_TIMER)) {
60 		return 0;
61 	}
62 
63 	do {
64 		static int in_hardclock = 0;
65 		int s;
66 
67 		timer = (volatile struct timer_reg *)IIOV(NEXT_P_TIMER);
68 		timer->csr |= TIMER_REG_UPDATE;
69 
70 		if (!in_hardclock) {
71 			in_hardclock = 1;
72 			s = splclock ();
73 			hardclock(arg);
74 			splx(s);
75 			in_hardclock = 0;
76 		}
77 		if (whilecount++ > 10)
78 			panic ("whilecount");
79 	} while (INTR_OCCURRED(NEXT_I_TIMER));
80 	return 1;
81 }
82 
83 /*
84  * Set up the real-time and statistics clocks.  Leave stathz 0 only
85  * if no alternative timer is available.
86  *
87  * The frequencies of these clocks must be an even number of microseconds.
88  */
89 void
cpu_initclocks(void)90 cpu_initclocks(void)
91 {
92 	int s, cnt;
93 	volatile struct timer_reg *timer;
94 
95 	rtc_init();
96 	hz = 100;
97 	s = splclock();
98 	timer = (volatile struct timer_reg *)IIOV(NEXT_P_TIMER);
99 	cnt = 1000000/hz;          /* usec timer */
100 	timer->csr = 0;
101 	timer->msb = (cnt >> 8);
102 	timer->lsb = cnt;
103 	timer->csr = TIMER_REG_ENABLE|TIMER_REG_UPDATE;
104 	isrlink_autovec(clock_intr, NULL, NEXT_I_IPL(NEXT_I_TIMER), 0, NULL);
105 	INTR_ENABLE(NEXT_I_TIMER);
106 	splx(s);
107 }
108 
109 
110 void
setstatclockrate(int newhz)111 setstatclockrate(int newhz)
112 {
113 
114 	/* XXX should we do something here? XXX */
115 }
116 
117 /*
118  * @@@ update this to use the usec timer
119  * Darrin B Jewell <jewell@mit.edu>  Sun Feb  8 05:01:02 1998
120  * XXX: Well, there is no more microtime.  But if there is a hardware
121  * timer of any sort, it could be added.   ENODOCS.  gdamore.
122  */
123 
124