xref: /netbsd-src/sys/arch/arm/ofw/ofwgencfg_clock.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: ofwgencfg_clock.c,v 1.7 2007/03/08 20:48:39 matt 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 1.7 2007/03/08 20:48:39 matt 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
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(frame)
83 	struct clockframe *frame;
84 {
85 
86 	statclock(frame);
87 	return(0);	/* Pass the interrupt on down the chain */
88 }
89 #endif
90 
91 /*
92  * void setstatclockrate(int hz)
93  *
94  * Set the stat clock rate. The stat clock uses timer1
95  */
96 
97 void
98 setstatclockrate(int arg)
99 {
100 #ifdef	OFWGENCFG
101 	printf("Not setting statclock: OFW generic has only one clock.\n");
102 #endif
103 }
104 
105 
106 /*
107  * void cpu_initclocks(void)
108  *
109  * Initialise the clocks.
110  * This sets up the two timers in the IOMD and installs the IRQ handlers
111  *
112  * NOTE: Currently only timer 0 is setup and the IRQ handler is not installed
113  */
114 
115 void
116 cpu_initclocks()
117 {
118 	/*
119 	 * Load timer 0 with count down value
120 	 * This timer generates 100Hz interrupts for the system clock
121 	 */
122 
123 	printf("clock: hz=%d stathz = %d profhz = %d\n", hz, stathz, profhz);
124 
125         clockirq = intr_claim(IRQ_TIMER0, IPL_CLOCK,
126             (int (*)(void *))clockhandler, 0, "clock", "hard intr");
127         if (clockirq == NULL)
128                 panic("Cannot installer timer 0 IRQ handler");
129 
130 	/* Notify callback handler that it can start processing ticks. */
131 	ofw_handleticks = 1;
132 
133 	if (stathz) {
134 	    printf("Not installing statclock: OFW generic has only one clock.\n");
135 	}
136 }
137 
138 
139 /*
140  * void microtime(struct timeval *tvp)
141  *
142  * Fill in the specified timeval struct with the current time
143  * accurate to the microsecond.
144  */
145 
146 void
147 microtime(tvp)
148 	struct timeval *tvp;
149 {
150 	int s;
151 	static struct timeval oldtv;
152 
153 	s = splhigh();
154 
155 	/* Fill in the timeval struct */
156 
157 	*tvp = time;
158 
159 	/* Make sure the micro seconds don't overflow. */
160 
161 	while (tvp->tv_usec >= 1000000) {
162 		tvp->tv_usec -= 1000000;
163 		++tvp->tv_sec;
164 	}
165 
166 	/* Make sure the time has advanced. */
167 
168 	if (tvp->tv_sec == oldtv.tv_sec &&
169 	    tvp->tv_usec <= oldtv.tv_usec) {
170 		tvp->tv_usec = oldtv.tv_usec + 1;
171 		if (tvp->tv_usec >= 1000000) {
172 			tvp->tv_usec -= 1000000;
173 			++tvp->tv_sec;
174 		}
175 	}
176 
177 
178 	oldtv = *tvp;
179 	(void)splx(s);
180 }
181 
182 /*
183  * Estimated loop for n microseconds
184  */
185 
186 /* Need to re-write this to use the timers */
187 
188 /* One day soon I will actually do this */
189 
190 int delaycount = 50;
191 
192 void
193 delay(n)
194 	u_int n;
195 {
196 	u_int i;
197 
198 	if (n == 0) return;
199 	while (n-- > 0) {
200 		if (cputype == CPU_ID_SA110)	/* XXX - Seriously gross hack */
201 			for (i = delaycount; --i;);
202 		else
203 			for (i = 8; --i;);
204 	}
205 }
206