/* $NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh Exp $ */ /*- * Copyright (c) 2005 David Young. All rights reserved. * * This code was written by David Young. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY * OF SUCH DAMAGE. */ /*- * Copyright (c) 2002 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Device driver for the watchdog timer built into the * AMD Geode SC1100 processor. */ #include __KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.12 2016/07/11 11:31:49 msaitoh Exp $"); #include #include #include #include #include #include #include #include #include #include #include #ifdef GEODE_DEBUG #define GEODE_DPRINTF(__x) printf __x #else /* GEODE_DEBUG */ #define GEODE_DPRINTF(__x) /* nothing */ #endif struct geode_wdog_softc { struct geode_gcb_softc *sc_gcb_dev; uint16_t sc_countdown; uint8_t sc_prescale; struct sysmon_wdog sc_smw; }; static int attached = 0; static void geode_wdog_disable(struct geode_wdog_softc *sc) { uint16_t wdcnfg; /* cancel any pending countdown */ sc->sc_countdown = 0; bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO, 0); /* power-down clock */ wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG); GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); wdcnfg |= SC1100_WDCNFG_WD32KPD; wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK); /* This no-op is for the reader's benefit. */ wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION | SC1100_WDCNFG_WDTYPE2_NOACTION; bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg); GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); } static void geode_wdog_enable(struct geode_wdog_softc *sc) { uint16_t wdcnfg; /* power-up clock and set prescale */ wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG); GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK | SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK); wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK); wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION; bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg); GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); } static void geode_wdog_reset(struct geode_wdog_softc *sc) { /* set countdown */ bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO, sc->sc_countdown); } static int geode_wdog_tickle(struct sysmon_wdog *smw) { int s; struct geode_wdog_softc *sc = smw->smw_cookie; s = splhigh(); geode_wdog_reset(sc); splx(s); return 0; } static int geode_wdog_setmode(struct sysmon_wdog *smw) { struct geode_wdog_softc *sc = smw->smw_cookie; uint32_t ticks; int prescale, s; if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { s = splhigh(); geode_wdog_disable(sc); splx(s); return 0; } if (smw->smw_period == WDOG_PERIOD_DEFAULT) smw->smw_period = 32; else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */ return EINVAL; GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period)); ticks = smw->smw_period * SC1100_WDCLK_HZ; GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks)); for (prescale = 0; ticks > UINT16_MAX; prescale++) ticks /= 2; GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks)); GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale)); KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX); KASSERT(ticks <= UINT16_MAX); s = splhigh(); sc->sc_prescale = (uint8_t)prescale; sc->sc_countdown = (uint16_t)ticks; geode_wdog_enable(sc); geode_wdog_reset(sc); splx(s); return 0; } static int geode_wdog_match(device_t parent, cfdata_t match, void *aux) { return !attached; } static void geode_wdog_attach(device_t parent, device_t self, void *aux) { struct geode_wdog_softc *sc = device_private(self); uint8_t wdsts; aprint_naive(": Watchdog Timer\n"); aprint_normal(": AMD Geode SC1100 Watchdog Timer\n"); /* * Hook up the watchdog timer. */ sc->sc_gcb_dev = device_private(parent); sc->sc_smw.smw_name = device_xname(self); sc->sc_smw.smw_cookie = sc; sc->sc_smw.smw_setmode = geode_wdog_setmode; sc->sc_smw.smw_tickle = geode_wdog_tickle; sc->sc_smw.smw_period = 32; /* * Determine cause of the last reset, and issue a warning if it * was due to watchdog expiry. */ wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS); GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", device_xname(self), wdsts)); if (wdsts & SC1100_WDSTS_WDRST) aprint_error( "%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n", device_xname(self)); /* reset WDOVF by writing 1 to it */ bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS, wdsts & SC1100_WDSTS_WDOVF); if (sysmon_wdog_register(&sc->sc_smw) != 0) aprint_error("%s: unable to register watchdog with sysmon\n", device_xname(self)); /* cancel any pending countdown */ geode_wdog_disable(sc); attached = 1; } static int geode_wdog_detach(device_t self, int flags) { int rc; struct geode_wdog_softc *sc = device_private(self); if ((rc = sysmon_wdog_unregister(&sc->sc_smw)) != 0) { if (rc == ERESTART) rc = EINTR; return rc; } /* cancel any pending countdown */ geode_wdog_disable(sc); attached = 0; return 0; } CFATTACH_DECL_NEW(geodewdog, sizeof(struct geode_wdog_softc), geode_wdog_match, geode_wdog_attach, geode_wdog_detach, NULL);