xref: /netbsd-src/sys/arch/sh3/dev/wdog.c (revision 0dd5877adce57db949b16ae963e5a6831cccdfb6)
1 /* $NetBSD: wdog.c,v 1.5 2002/02/12 15:26:46 uch 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 
41 #include <machine/cpu.h>
42 #include <machine/conf.h>
43 #include <sh3/frame.h>
44 #include <sh3/shbvar.h>
45 #include <sh3/wdtreg.h>
46 #include <sh3/wdogvar.h>
47 
48 struct wdog_softc {
49 	struct device sc_dev;		/* generic device structures */
50 	unsigned int iobase;
51 	int flags;
52 };
53 
54 static int wdogmatch(struct device *, struct cfdata *, void *);
55 static void wdogattach(struct device *, struct device *, void *);
56 static int wdogintr(void *);
57 
58 struct cfattach wdog_ca = {
59 	sizeof(struct wdog_softc), wdogmatch, wdogattach
60 };
61 
62 extern struct cfdriver wdog_cd;
63 
64 void
65 wdog_wr_cnt(unsigned char x)
66 {
67 
68 	SHREG_WTCNT_W = WTCNT_W_M | (unsigned short) x;
69 }
70 
71 void
72 wdog_wr_csr(unsigned char x)
73 {
74 
75 	SHREG_WTCSR_W = WTCSR_W_M | (unsigned short) x;
76 }
77 
78 static int
79 wdogmatch(struct device *parent, struct cfdata *cfp, void *aux)
80 {
81 	struct shb_attach_args *sa = aux;
82 
83 	if (strcmp(cfp->cf_driver->cd_name, "wdog"))
84 		return 0;
85 
86 	sa->ia_iosize = 4;	/* XXX */
87 
88 	return (1);
89 }
90 
91 /*
92  *  functions for probeing.
93  */
94 /* ARGSUSED */
95 static void
96 wdogattach(struct device *parent, struct device *self, void *aux)
97 {
98 	struct wdog_softc *sc = (struct wdog_softc *)self;
99 	struct shb_attach_args *sa = aux;
100 
101 	sc->iobase = sa->ia_iobase;
102 	sc->flags = 0;
103 
104 	wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096);	/* default to wt mode */
105 
106 	shb_intr_establish(WDOG_IRQ, IST_EDGE, IPL_SOFTCLOCK, wdogintr, 0);
107 
108 	printf("\nwdog0: internal watchdog timer\n");
109 }
110 
111 /*ARGSUSED*/
112 int
113 wdogopen(dev_t dev, int flag, int mode, struct proc *p)
114 {
115 	struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
116 
117 	if (minor(dev) != 0)
118 		return (ENXIO);
119 	if (sc->flags & WDOGF_OPEN)
120 		return (EBUSY);
121 	sc->flags |= WDOGF_OPEN;
122 	return (0);
123 }
124 
125 /*ARGSUSED*/
126 int
127 wdogclose(dev_t dev, int flag, int mode, struct proc *p)
128 {
129 	struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */
130 
131 	if (sc->flags & WDOGF_OPEN)
132 		sc->flags = 0;
133 
134 	return (0);
135 }
136 
137 extern unsigned int maxwdog;
138 
139 /*ARGSUSED*/
140 int
141 wdogioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
142 {
143 	int error = 0;
144 	int request;
145 
146 	switch (cmd) {
147 	case SIOWDOGSETMODE:
148 		request = *(int *)data;
149 
150 		switch (request) {
151 		case WDOGM_RESET:
152 			wdog_wr_csr(SHREG_WTCSR_R | WTCSR_WT);
153 			break;
154 		case WDOGM_INTR:
155 			wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_WT);
156 			break;
157 		default:
158 			error = EINVAL;
159 			break;
160 		}
161 		break;
162 	case SIORESETWDOG:
163 		wdog_wr_cnt(0);		/* reset to zero */
164 		break;
165 	case SIOSTARTWDOG:
166 		wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096);
167 		wdog_wr_cnt(0);		/* reset to zero */
168 		wdog_wr_csr(SHREG_WTCSR_R | WTCSR_TME);	/* start!!! */
169 		break;
170 	case SIOSTOPWDOG:
171 		wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_TME); /* stop */
172 		break;
173 	case SIOSETWDOG:
174 		request = *(int *)data;
175 
176 		if (request > 2) {
177 			error = EINVAL;
178 			break;
179 		}
180 		break;
181 	default:
182 		error = EINVAL;
183 		break;
184 	}
185 
186 	return (error);
187 }
188 
189 int
190 wdogintr(void *arg)
191 {
192 	struct trapframe *frame = arg;
193 
194 	wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_IOVF); /* clear overflow bit */
195 	wdog_wr_cnt(0);			/* reset to zero */
196 	printf("wdog trapped: spc = %x\n", frame->tf_spc);
197 
198 	return (0);
199 }
200