1 /* $NetBSD: i80321_wdog.c,v 1.8 2005/12/24 20:06:52 perry Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Jason R. Thorpe 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 Intel i80321 I/O processor. 40 */ 41 42 #include <sys/cdefs.h> 43 __KERNEL_RCSID(0, "$NetBSD: i80321_wdog.c,v 1.8 2005/12/24 20:06:52 perry Exp $"); 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/device.h> 48 #include <sys/wdog.h> 49 50 #include <machine/bus.h> 51 #include <arm/cpufunc.h> 52 53 #include <arm/xscale/i80321reg.h> 54 #include <arm/xscale/i80321var.h> 55 56 #include <dev/sysmon/sysmonvar.h> 57 58 struct iopwdog_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 static inline void 66 wdtcr_write(uint32_t val) 67 { 68 69 __asm volatile("mcr p6, 0, %0, c7, c1, 0" 70 : 71 : "r" (val)); 72 } 73 74 static int 75 iopwdog_tickle(struct sysmon_wdog *smw) 76 { 77 78 wdtcr_write(WDTCR_ENABLE1); 79 wdtcr_write(WDTCR_ENABLE2); 80 return (0); 81 } 82 83 static int 84 iopwdog_setmode(struct sysmon_wdog *smw) 85 { 86 struct iopwdog_softc *sc = smw->smw_cookie; 87 88 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 89 /* The i80321 watchdog can't be disarmed once armed. */ 90 if (sc->sc_wdog_armed) 91 return (EOPNOTSUPP); 92 } else { 93 if (smw->smw_period == WDOG_PERIOD_DEFAULT) 94 smw->smw_period = sc->sc_wdog_period; 95 else if (smw->smw_period != sc->sc_wdog_period) { 96 /* Can't change the i80321 watchdog period. */ 97 return (EOPNOTSUPP); 98 } 99 sc->sc_wdog_armed = 1; 100 /* Watchdog is armed by tickling it. */ 101 iopwdog_tickle(smw); 102 } 103 return (0); 104 } 105 106 static int 107 iopwdog_match(struct device *parent, struct cfdata *cf, void *aux) 108 { 109 struct iopxs_attach_args *ia = aux; 110 111 if (strcmp(cf->cf_name, ia->ia_name) == 0) 112 return (1); 113 114 return (0); 115 } 116 117 static void 118 iopwdog_attach(struct device *parent, struct device *self, void *aux) 119 { 120 struct iopwdog_softc *sc = (void *) self; 121 122 /* 123 * XXX Should compute the period based on processor speed. 124 * For a 600MHz XScale core, the wdog must be tickled approx. 125 * every 7 seconds. 126 */ 127 sc->sc_wdog_period = 7; 128 129 aprint_naive(": Watchdog timer\n"); 130 aprint_normal(": %d second period\n", sc->sc_wdog_period); 131 132 sc->sc_smw.smw_name = sc->sc_dev.dv_xname; 133 sc->sc_smw.smw_cookie = sc; 134 sc->sc_smw.smw_setmode = iopwdog_setmode; 135 sc->sc_smw.smw_tickle = iopwdog_tickle; 136 sc->sc_smw.smw_period = sc->sc_wdog_period; 137 138 if (sysmon_wdog_register(&sc->sc_smw) != 0) 139 aprint_error("%s: unable to register with sysmon\n", 140 sc->sc_dev.dv_xname); 141 } 142 143 CFATTACH_DECL(iopwdog, sizeof(struct iopwdog_softc), 144 iopwdog_match, iopwdog_attach, NULL, NULL); 145