1 /* $NetBSD: ofwgencfg_clock.c,v 1.10 2009/03/18 10:22:24 cegger Exp $ */
2
3 /*
4 * Copyright 1997
5 * Digital Equipment Corporation. All rights reserved.
6 *
7 * This software is furnished under license and may be used and
8 * copied only in accordance with the following terms and conditions.
9 * Subject to these conditions, you may download, copy, install,
10 * use, modify and distribute this software in source and/or binary
11 * form. No title or ownership is transferred hereby.
12 *
13 * 1) Any source code used, modified or distributed must reproduce
14 * and retain this copyright notice and list of conditions as
15 * they appear in the source file.
16 *
17 * 2) No right is granted to use any trade name, trademark, or logo of
18 * Digital Equipment Corporation. Neither the "Digital Equipment
19 * Corporation" name nor any trademark or logo of Digital Equipment
20 * Corporation may be used to endorse or promote products derived
21 * from this software without the prior written permission of
22 * Digital Equipment Corporation.
23 *
24 * 3) This software is provided "AS-IS" and any express or implied
25 * warranties, including but not limited to, any implied warranties
26 * of merchantability, fitness for a particular purpose, or
27 * non-infringement are disclaimed. In no event shall DIGITAL be
28 * liable for any damages whatsoever, and in particular, DIGITAL
29 * shall not be liable for special, indirect, consequential, or
30 * incidental damages or damages for lost profits, loss of
31 * revenue or loss of use, whether such damages arise in contract,
32 * negligence, tort, under statute, in equity, at law or otherwise,
33 * even if advised of the possibility of such damage.
34 */
35
36 /* Include header files */
37
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: ofwgencfg_clock.c,v 1.10 2009/03/18 10:22:24 cegger Exp $");
40
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/kernel.h>
45 #include <sys/time.h>
46
47 #include <machine/intr.h>
48 #include <machine/irqhandler.h>
49 #include <arm/cpufunc.h>
50 #include <machine/cpu.h>
51 #include <machine/ofw.h>
52
53 static void *clockirq;
54
55
56 /*
57 * int clockhandler(struct clockframe *frame)
58 *
59 * Function called by timer 0 interrupts. This just calls
60 * hardclock(). Eventually the irqhandler can call hardclock() directly
61 * but for now we use this function so that we can debug IRQ's
62 */
63
64 static int
clockhandler(struct clockframe * frame)65 clockhandler(struct clockframe *frame)
66 {
67
68 hardclock(frame);
69 return(0); /* Pass the interrupt on down the chain */
70 }
71
72 #if 0
73 /*
74 * int statclockhandler(struct clockframe *frame)
75 *
76 * Function called by timer 1 interrupts. This just calls
77 * statclock(). Eventually the irqhandler can call statclock() directly
78 * but for now we use this function so that we can debug IRQ's
79 */
80
81 int
82 statclockhandler(struct clockframe *frame)
83 {
84
85 statclock(frame);
86 return(0); /* Pass the interrupt on down the chain */
87 }
88 #endif
89
90 /*
91 * void setstatclockrate(int hz)
92 *
93 * Set the stat clock rate. The stat clock uses timer1
94 */
95
96 void
setstatclockrate(int arg)97 setstatclockrate(int arg)
98 {
99 #ifdef OFWGENCFG
100 printf("Not setting statclock: OFW generic has only one clock.\n");
101 #endif
102 }
103
104
105 /*
106 * void cpu_initclocks(void)
107 *
108 * Initialise the clocks.
109 * This sets up the two timers in the IOMD and installs the IRQ handlers
110 *
111 * NOTE: Currently only timer 0 is setup and the IRQ handler is not installed
112 */
113
114 void
cpu_initclocks(void)115 cpu_initclocks(void)
116 {
117 /*
118 * Load timer 0 with count down value
119 * This timer generates 100Hz interrupts for the system clock
120 */
121
122 printf("clock: hz=%d stathz = %d profhz = %d\n", hz, stathz, profhz);
123
124 clockirq = intr_claim(IRQ_TIMER0, IPL_CLOCK,
125 (int (*)(void *))clockhandler, 0, "clock", "hard intr");
126 if (clockirq == NULL)
127 panic("Cannot installer timer 0 IRQ handler");
128
129 /* Notify callback handler that it can start processing ticks. */
130 ofw_handleticks = 1;
131
132 if (stathz) {
133 printf("Not installing statclock: OFW generic has only one clock.\n");
134 }
135 }
136
137 /*
138 * Estimated loop for n microseconds
139 */
140
141 /* Need to re-write this to use the timers */
142
143 /* One day soon I will actually do this */
144
145 int delaycount = 50;
146
147 void
delay(u_int n)148 delay(u_int n)
149 {
150 u_int i;
151
152 if (n == 0) return;
153 while (n-- > 0) {
154 if (cputype == CPU_ID_SA110) /* XXX - Seriously gross hack */
155 for (i = delaycount; --i;);
156 else
157 for (i = 8; --i;);
158 }
159 }
160