xref: /netbsd-src/sys/arch/sh3/dev/wdog.c (revision 08c81a9c2dc8c7300e893321eb65c0925d60871c)
1 /* $NetBSD: wdog.c,v 1.7 2002/09/06 13:18:43 gehenna Exp $ */
2 
3 /*-
4  * Copyright (C) 2000 SAITOH Masanobu.  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  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/buf.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/uio.h>
34 #include <sys/device.h>
35 #include <sys/fcntl.h>
36 #include <sys/ioctl.h>
37 #include <sys/malloc.h>
38 #include <sys/proc.h>
39 #include <sys/syslog.h>
40 #include <sys/conf.h>
41 
42 #include <machine/cpu.h>
43 #include <machine/intr.h>
44 
45 #include <sh3/frame.h>
46 #include <sh3/wdtreg.h>
47 #include <sh3/wdogvar.h>
48 #include <sh3/exception.h>
49 
50 struct wdog_softc {
51 	struct device sc_dev;		/* generic device structures */
52 	int flags;
53 };
54 
55 static int wdogmatch(struct device *, struct cfdata *, void *);
56 static void wdogattach(struct device *, struct device *, void *);
57 static int wdogintr(void *);
58 
59 struct cfattach wdog_ca = {
60 	sizeof(struct wdog_softc), wdogmatch, wdogattach
61 };
62 
63 extern struct cfdriver wdog_cd;
64 
65 dev_type_open(wdogopen);
66 dev_type_close(wdogclose);
67 dev_type_ioctl(wdogioctl);
68 
69 const struct cdevsw wdog_cdevsw = {
70 	wdogopen, wdogclose, noread, nowrite, wdogioctl,
71 	nostop, notty, nopoll, nommap,
72 };
73 
74 void
75 wdog_wr_cnt(unsigned char x)
76 {
77 
78 	SHREG_WTCNT_W = WTCNT_W_M | (unsigned short) x;
79 }
80 
81 void
82 wdog_wr_csr(unsigned char x)
83 {
84 
85 	SHREG_WTCSR_W = WTCSR_W_M | (unsigned short) x;
86 }
87 
88 static int
89 wdogmatch(struct device *parent, struct cfdata *cfp, void *aux)
90 {
91 
92 	if (strcmp(cfp->cf_driver->cd_name, "wdog"))
93 		return (0);
94 
95 	return (1);
96 }
97 
98 /*
99  *  functions for probeing.
100  */
101 /* ARGSUSED */
102 static void
103 wdogattach(struct device *parent, struct device *self, void *aux)
104 {
105 	struct wdog_softc *sc = (struct wdog_softc *)self;
106 
107 	sc->flags = 0;
108 
109 	wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096);	/* default to wt mode */
110 
111 	intc_intr_establish(SH_INTEVT_WDT_ITI, IST_LEVEL, IPL_SOFTCLOCK,
112 	    wdogintr, 0);
113 
114 	printf("\nwdog0: internal watchdog timer\n");
115 }
116 
117 /*ARGSUSED*/
118 int
119 wdogopen(dev_t dev, int flag, int mode, struct proc *p)
120 {
121 	struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
122 
123 	if (minor(dev) != 0)
124 		return (ENXIO);
125 	if (sc->flags & WDOGF_OPEN)
126 		return (EBUSY);
127 	sc->flags |= WDOGF_OPEN;
128 	return (0);
129 }
130 
131 /*ARGSUSED*/
132 int
133 wdogclose(dev_t dev, int flag, int mode, struct proc *p)
134 {
135 	struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
136 
137 	if (sc->flags & WDOGF_OPEN)
138 		sc->flags = 0;
139 
140 	return (0);
141 }
142 
143 extern unsigned int maxwdog;
144 
145 /*ARGSUSED*/
146 int
147 wdogioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
148 {
149 	int error = 0;
150 	int request;
151 
152 	switch (cmd) {
153 	case SIOWDOGSETMODE:
154 		request = *(int *)data;
155 
156 		switch (request) {
157 		case WDOGM_RESET:
158 			wdog_wr_csr(SHREG_WTCSR_R | WTCSR_WT);
159 			break;
160 		case WDOGM_INTR:
161 			wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_WT);
162 			break;
163 		default:
164 			error = EINVAL;
165 			break;
166 		}
167 		break;
168 	case SIORESETWDOG:
169 		wdog_wr_cnt(0);		/* reset to zero */
170 		break;
171 	case SIOSTARTWDOG:
172 		wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096);
173 		wdog_wr_cnt(0);		/* reset to zero */
174 		wdog_wr_csr(SHREG_WTCSR_R | WTCSR_TME);	/* start!!! */
175 		break;
176 	case SIOSTOPWDOG:
177 		wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_TME); /* stop */
178 		break;
179 	case SIOSETWDOG:
180 		request = *(int *)data;
181 
182 		if (request > 2) {
183 			error = EINVAL;
184 			break;
185 		}
186 		break;
187 	default:
188 		error = EINVAL;
189 		break;
190 	}
191 
192 	return (error);
193 }
194 
195 int
196 wdogintr(void *arg)
197 {
198 	struct trapframe *frame = arg;
199 
200 	wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_IOVF); /* clear overflow bit */
201 	wdog_wr_cnt(0);			/* reset to zero */
202 	printf("wdog trapped: spc = %x\n", frame->tf_spc);
203 
204 	return (0);
205 }
206