1 /* $NetBSD: wdog.c,v 1.2 2002/08/12 02:06:21 simonb Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Jason R. Thorpe and Simon Burge for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * Watchdog timer support for the IBM 405GP processor. 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/device.h> 45 #include <sys/properties.h> 46 #include <sys/wdog.h> 47 48 #include <powerpc/spr.h> 49 #include <powerpc/ibm4xx/dev/opbvar.h> 50 51 #include <dev/sysmon/sysmonvar.h> 52 53 static int wdog_match(struct device *, struct cfdata *, void *); 54 static void wdog_attach(struct device *, struct device *, void *); 55 static int wdog_tickle(struct sysmon_wdog *); 56 static int wdog_setmode(struct sysmon_wdog *); 57 58 struct wdog_softc { 59 struct device sc_dev; 60 struct sysmon_wdog sc_smw; 61 int sc_wdog_armed; 62 int sc_wdog_period; 63 }; 64 65 struct cfattach wdog_ca = { 66 sizeof(struct wdog_softc), wdog_match, wdog_attach, 67 }; 68 69 static int 70 wdog_match(struct device *parent, struct cfdata *cf, void *aux) 71 { 72 struct opb_attach_args *oaa = aux; 73 74 /* match only watchdog devices */ 75 if (strcmp(oaa->opb_name, cf->cf_driver->cd_name) != 0) 76 return (0); 77 78 return (1); 79 } 80 81 static void 82 wdog_attach(struct device *parent, struct device *self, void *aux) 83 { 84 struct wdog_softc *sc = (void *)self; 85 unsigned int processor_freq; 86 87 if (board_info_get("processor-frequency", 88 &processor_freq, sizeof(processor_freq)) == -1) 89 processor_freq = 200 * 1000 * 1000; /* assume 200MHz */ 90 91 sc->sc_wdog_period = (2LL << 29) / processor_freq; 92 printf(": %d second period\n", sc->sc_wdog_period); 93 94 sc->sc_smw.smw_name = sc->sc_dev.dv_xname; 95 sc->sc_smw.smw_cookie = sc; 96 sc->sc_smw.smw_setmode = wdog_setmode; 97 sc->sc_smw.smw_tickle = wdog_tickle; 98 sc->sc_smw.smw_period = sc->sc_wdog_period; 99 100 if (sysmon_wdog_register(&sc->sc_smw) != 0) 101 printf("%s: unable to register with sysmon\n", 102 sc->sc_dev.dv_xname); 103 104 } 105 106 static int 107 wdog_tickle(struct sysmon_wdog *smw) 108 { 109 uint32_t tsr; 110 111 tsr = mfspr(SPR_TSR); 112 tsr |= TSR_ENW | TSR_WIS; 113 mtspr(SPR_TSR, tsr); 114 return (0); 115 } 116 117 static int 118 wdog_setmode(struct sysmon_wdog *smw) 119 { 120 struct wdog_softc *sc = smw->smw_cookie; 121 uint32_t tcr, tsr; 122 123 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 124 if (sc->sc_wdog_armed) { 125 tsr = mfspr(SPR_TSR); 126 tsr &= ~(TSR_ENW | TSR_WIS); 127 mtspr(SPR_TSR, tsr); 128 } 129 } else { 130 if (smw->smw_period == WDOG_PERIOD_DEFAULT) 131 smw->smw_period = sc->sc_wdog_period; 132 else if (smw->smw_period != sc->sc_wdog_period) { 133 /* 134 * There's 4 set watchdog periods on the 405GP, 135 * but we only support the longest one (2.684 136 * seconds). 137 */ 138 return (EOPNOTSUPP); 139 } 140 sc->sc_wdog_armed = 1; 141 142 tcr = mfspr(SPR_TCR); 143 tcr |= TCR_WP_2_29 | TCR_WRC_SYSTEM; 144 mtspr(SPR_TCR, tcr); 145 146 /* Arm the watchdog. */ 147 wdog_tickle(smw); 148 } 149 return (0); 150 } 151