1/* $NetBSD: wdog.c,v 1.11 2011/06/17 19:03:02 matt 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/cdefs.h> 43__KERNEL_RCSID(0, "$NetBSD: wdog.c,v 1.11 2011/06/17 19:03:02 matt Exp $"); 44 45#include <sys/param.h> 46#include <sys/systm.h> 47#include <sys/device.h> 48#include <sys/cpu.h> 49#include <sys/wdog.h> 50 51#include <prop/proplib.h> 52 53#include <powerpc/spr.h> 54#include <powerpc/ibm4xx/spr.h> 55#include <powerpc/ibm4xx/cpu.h> 56#include <powerpc/ibm4xx/dev/opbvar.h> 57 58#include <dev/sysmon/sysmonvar.h> 59 60static int wdog_match(device_t, cfdata_t, void *); 61static void wdog_attach(device_t, device_t, void *); 62static int wdog_tickle(struct sysmon_wdog *); 63static int wdog_setmode(struct sysmon_wdog *); 64 65struct wdog_softc { 66 device_t sc_dev; 67 struct sysmon_wdog sc_smw; 68 bool sc_wdog_armed; 69 int sc_wdog_period; 70}; 71 72CFATTACH_DECL_NEW(wdog, sizeof(struct wdog_softc), 73 wdog_match, wdog_attach, NULL, NULL); 74 75static int 76wdog_match(device_t parent, cfdata_t cf, void *aux) 77{ 78 struct opb_attach_args * const oaa = aux; 79 80 /* match only watchdog devices */ 81 if (strcmp(oaa->opb_name, cf->cf_name) != 0) 82 return (0); 83 84 return (1); 85} 86 87static void 88wdog_attach(device_t parent, device_t self, void *aux) 89{ 90 struct wdog_softc * const sc = device_private(self); 91 unsigned int processor_freq; 92 prop_number_t freq; 93 94 freq = prop_dictionary_get(board_properties, "processor-frequency"); 95 KASSERT(freq != NULL); 96 processor_freq = (unsigned int) prop_number_integer_value(freq); 97 98 sc->sc_wdog_period = (2LL << 29) / processor_freq; 99 aprint_normal(": %d second period\n", sc->sc_wdog_period); 100 101 sc->sc_dev = self; 102 sc->sc_smw.smw_name = device_xname(self); 103 sc->sc_smw.smw_cookie = sc; 104 sc->sc_smw.smw_setmode = wdog_setmode; 105 sc->sc_smw.smw_tickle = wdog_tickle; 106 sc->sc_smw.smw_period = sc->sc_wdog_period; 107 108 if (sysmon_wdog_register(&sc->sc_smw) != 0) 109 aprint_error_dev(self, "unable to register with sysmon\n"); 110} 111 112static int 113wdog_tickle(struct sysmon_wdog *smw) 114{ 115 uint32_t tsr; 116 117 tsr = mfspr(SPR_TSR); 118 tsr |= TSR_ENW | TSR_WIS; 119 mtspr(SPR_TSR, tsr); 120 return (0); 121} 122 123static int 124wdog_setmode(struct sysmon_wdog *smw) 125{ 126 struct wdog_softc * const sc = smw->smw_cookie; 127 128 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 129 if (sc->sc_wdog_armed) { 130 uint32_t tsr = mfspr(SPR_TSR); 131 tsr &= ~(TSR_ENW | TSR_WIS); 132 mtspr(SPR_TSR, tsr); 133 sc->sc_wdog_armed = false; 134 } 135 } else { 136 if (smw->smw_period == WDOG_PERIOD_DEFAULT) 137 smw->smw_period = sc->sc_wdog_period; 138 else if (smw->smw_period != sc->sc_wdog_period) { 139 /* 140 * There's 4 set watchdog periods on the 405GP, 141 * but we only support the longest one (2.684 142 * seconds). 143 */ 144 return (EOPNOTSUPP); 145 } 146 sc->sc_wdog_armed = true; 147 148 uint32_t tcr = mfspr(SPR_TCR); 149 tcr |= TCR_WP_2_29 | TCR_WRC_SYSTEM; 150 mtspr(SPR_TCR, tcr); 151 152 /* Arm the watchdog. */ 153 wdog_tickle(smw); 154 } 155 return (0); 156} 157