wdog.c revision 1.11 1 /* $NetBSD: wdog.c,v 1.11 2002/10/02 15:52:35 thorpej 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 CFATTACH_DECL(wdog, sizeof(struct wdog_softc),
60 wdogmatch, wdogattach, NULL, NULL);
61
62 extern struct cfdriver wdog_cd;
63
64 dev_type_open(wdogopen);
65 dev_type_close(wdogclose);
66 dev_type_ioctl(wdogioctl);
67
68 const struct cdevsw wdog_cdevsw = {
69 wdogopen, wdogclose, noread, nowrite, wdogioctl,
70 nostop, notty, nopoll, nommap,
71 };
72
73 void
74 wdog_wr_cnt(unsigned char x)
75 {
76
77 SHREG_WTCNT_W = WTCNT_W_M | (unsigned short) x;
78 }
79
80 void
81 wdog_wr_csr(unsigned char x)
82 {
83
84 SHREG_WTCSR_W = WTCSR_W_M | (unsigned short) x;
85 }
86
87 static int
88 wdogmatch(struct device *parent, struct cfdata *cfp, void *aux)
89 {
90
91 if (strcmp(cfp->cf_name, "wdog"))
92 return (0);
93
94 return (1);
95 }
96
97 /*
98 * functions for probeing.
99 */
100 /* ARGSUSED */
101 static void
102 wdogattach(struct device *parent, struct device *self, void *aux)
103 {
104 struct wdog_softc *sc = (struct wdog_softc *)self;
105
106 sc->flags = 0;
107
108 wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096); /* default to wt mode */
109
110 intc_intr_establish(SH_INTEVT_WDT_ITI, IST_LEVEL, IPL_SOFTCLOCK,
111 wdogintr, 0);
112
113 printf("\nwdog0: internal watchdog timer\n");
114 }
115
116 /*ARGSUSED*/
117 int
118 wdogopen(dev_t dev, int flag, int mode, struct proc *p)
119 {
120 struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
121
122 if (minor(dev) != 0)
123 return (ENXIO);
124 if (sc->flags & WDOGF_OPEN)
125 return (EBUSY);
126 sc->flags |= WDOGF_OPEN;
127 return (0);
128 }
129
130 /*ARGSUSED*/
131 int
132 wdogclose(dev_t dev, int flag, int mode, struct proc *p)
133 {
134 struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
135
136 if (sc->flags & WDOGF_OPEN)
137 sc->flags = 0;
138
139 return (0);
140 }
141
142 extern unsigned int maxwdog;
143
144 /*ARGSUSED*/
145 int
146 wdogioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
147 {
148 int error = 0;
149 int request;
150
151 switch (cmd) {
152 case SIOWDOGSETMODE:
153 request = *(int *)data;
154
155 switch (request) {
156 case WDOGM_RESET:
157 wdog_wr_csr(SHREG_WTCSR_R | WTCSR_WT);
158 break;
159 case WDOGM_INTR:
160 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_WT);
161 break;
162 default:
163 error = EINVAL;
164 break;
165 }
166 break;
167 case SIORESETWDOG:
168 wdog_wr_cnt(0); /* reset to zero */
169 break;
170 case SIOSTARTWDOG:
171 wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096);
172 wdog_wr_cnt(0); /* reset to zero */
173 wdog_wr_csr(SHREG_WTCSR_R | WTCSR_TME); /* start!!! */
174 break;
175 case SIOSTOPWDOG:
176 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_TME); /* stop */
177 break;
178 case SIOSETWDOG:
179 request = *(int *)data;
180
181 if (request > 2) {
182 error = EINVAL;
183 break;
184 }
185 break;
186 default:
187 error = EINVAL;
188 break;
189 }
190
191 return (error);
192 }
193
194 int
195 wdogintr(void *arg)
196 {
197 struct trapframe *frame = arg;
198
199 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_IOVF); /* clear overflow bit */
200 wdog_wr_cnt(0); /* reset to zero */
201 printf("wdog trapped: spc = %x\n", frame->tf_spc);
202
203 return (0);
204 }
205