1 /* $NetBSD: wdog.c,v 1.13 2003/07/15 03:35:55 lukem 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/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: wdog.c,v 1.13 2003/07/15 03:35:55 lukem Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/buf.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/uio.h> 37 #include <sys/device.h> 38 #include <sys/fcntl.h> 39 #include <sys/ioctl.h> 40 #include <sys/malloc.h> 41 #include <sys/proc.h> 42 #include <sys/syslog.h> 43 #include <sys/conf.h> 44 45 #include <machine/cpu.h> 46 #include <machine/intr.h> 47 48 #include <sh3/frame.h> 49 #include <sh3/wdtreg.h> 50 #include <sh3/wdogvar.h> 51 #include <sh3/exception.h> 52 53 struct wdog_softc { 54 struct device sc_dev; /* generic device structures */ 55 int flags; 56 }; 57 58 static int wdogmatch(struct device *, struct cfdata *, void *); 59 static void wdogattach(struct device *, struct device *, void *); 60 static int wdogintr(void *); 61 62 CFATTACH_DECL(wdog, sizeof(struct wdog_softc), 63 wdogmatch, wdogattach, NULL, NULL); 64 65 extern struct cfdriver wdog_cd; 66 67 dev_type_open(wdogopen); 68 dev_type_close(wdogclose); 69 dev_type_ioctl(wdogioctl); 70 71 const struct cdevsw wdog_cdevsw = { 72 wdogopen, wdogclose, noread, nowrite, wdogioctl, 73 nostop, notty, nopoll, nommap, nokqfilter, 74 }; 75 76 void 77 wdog_wr_cnt(unsigned char x) 78 { 79 80 SHREG_WTCNT_W = WTCNT_W_M | (unsigned short) x; 81 } 82 83 void 84 wdog_wr_csr(unsigned char x) 85 { 86 87 SHREG_WTCSR_W = WTCSR_W_M | (unsigned short) x; 88 } 89 90 static int 91 wdogmatch(struct device *parent, struct cfdata *cfp, void *aux) 92 { 93 94 if (strcmp(cfp->cf_name, "wdog")) 95 return (0); 96 97 return (1); 98 } 99 100 /* 101 * functions for probeing. 102 */ 103 /* ARGSUSED */ 104 static void 105 wdogattach(struct device *parent, struct device *self, void *aux) 106 { 107 struct wdog_softc *sc = (struct wdog_softc *)self; 108 109 sc->flags = 0; 110 111 wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096); /* default to wt mode */ 112 113 intc_intr_establish(SH_INTEVT_WDT_ITI, IST_LEVEL, IPL_SOFTCLOCK, 114 wdogintr, 0); 115 116 printf("\nwdog0: internal watchdog timer\n"); 117 } 118 119 /*ARGSUSED*/ 120 int 121 wdogopen(dev_t dev, int flag, int mode, struct proc *p) 122 { 123 struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */ 124 125 if (minor(dev) != 0) 126 return (ENXIO); 127 if (sc->flags & WDOGF_OPEN) 128 return (EBUSY); 129 sc->flags |= WDOGF_OPEN; 130 return (0); 131 } 132 133 /*ARGSUSED*/ 134 int 135 wdogclose(dev_t dev, int flag, int mode, struct proc *p) 136 { 137 struct wdog_softc *sc = wdog_cd.cd_devs[0]; /* XXX */ 138 139 if (sc->flags & WDOGF_OPEN) 140 sc->flags = 0; 141 142 return (0); 143 } 144 145 extern unsigned int maxwdog; 146 147 /*ARGSUSED*/ 148 int 149 wdogioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p) 150 { 151 int error = 0; 152 int request; 153 154 switch (cmd) { 155 case SIOWDOGSETMODE: 156 request = *(int *)data; 157 158 switch (request) { 159 case WDOGM_RESET: 160 wdog_wr_csr(SHREG_WTCSR_R | WTCSR_WT); 161 break; 162 case WDOGM_INTR: 163 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_WT); 164 break; 165 default: 166 error = EINVAL; 167 break; 168 } 169 break; 170 case SIORESETWDOG: 171 wdog_wr_cnt(0); /* reset to zero */ 172 break; 173 case SIOSTARTWDOG: 174 wdog_wr_csr(WTCSR_WT | WTCSR_CKS_4096); 175 wdog_wr_cnt(0); /* reset to zero */ 176 wdog_wr_csr(SHREG_WTCSR_R | WTCSR_TME); /* start!!! */ 177 break; 178 case SIOSTOPWDOG: 179 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_TME); /* stop */ 180 break; 181 case SIOSETWDOG: 182 request = *(int *)data; 183 184 if (request > 2) { 185 error = EINVAL; 186 break; 187 } 188 break; 189 default: 190 error = EINVAL; 191 break; 192 } 193 194 return (error); 195 } 196 197 int 198 wdogintr(void *arg) 199 { 200 struct trapframe *frame = arg; 201 202 wdog_wr_csr(SHREG_WTCSR_R & ~WTCSR_IOVF); /* clear overflow bit */ 203 wdog_wr_cnt(0); /* reset to zero */ 204 printf("wdog trapped: spc = %x\n", frame->tf_spc); 205 206 return (0); 207 } 208