1 /* $NetBSD: geodewdg.c,v 1.5 2006/11/16 01:32:39 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2005 David Young. All rights reserved. 5 * 6 * This code was written by David Young. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by David Young. 19 * 4. The name of David Young may not be used to endorse or promote 20 * products derived from this software without specific prior 21 * written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY 24 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 25 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 26 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DAVID 27 * YOUNG BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 28 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 31 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 34 * OF SUCH DAMAGE. 35 */ 36 /*- 37 * Copyright (c) 2002 The NetBSD Foundation, Inc. 38 * All rights reserved. 39 * 40 * This code is derived from software contributed to The NetBSD Foundation 41 * by Jason R. Thorpe. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the NetBSD 54 * Foundation, Inc. and its contributors. 55 * 4. Neither the name of The NetBSD Foundation nor the names of its 56 * contributors may be used to endorse or promote products derived 57 * from this software without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 60 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 61 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 62 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 63 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 64 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 65 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 66 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 67 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 68 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 69 * POSSIBILITY OF SUCH DAMAGE. 70 */ 71 72 /* 73 * Device driver for the watchdog timer built into the 74 * AMD Geode SC1100 processor. 75 */ 76 77 #include <sys/cdefs.h> 78 79 __KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.5 2006/11/16 01:32:39 christos Exp $"); 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/device.h> 84 #include <sys/wdog.h> 85 #include <uvm/uvm_extern.h> 86 #include <machine/bus.h> 87 #include <dev/pci/pcivar.h> 88 #include <dev/pci/pcidevs.h> 89 #include <arch/i386/pci/geodevar.h> 90 #include <arch/i386/pci/geodereg.h> 91 #include <dev/sysmon/sysmonvar.h> 92 93 #ifdef GEODE_DEBUG 94 #define GEODE_DPRINTF(__x) printf __x 95 #else /* GEODE_DEBUG */ 96 #define GEODE_DPRINTF(__x) /* nothing */ 97 #endif 98 99 struct geode_wdog_softc { 100 struct device sc_dev; 101 struct geode_gcb_softc *sc_gcb_dev; 102 103 uint16_t sc_countdown; 104 uint8_t sc_prescale; 105 struct sysmon_wdog sc_smw; 106 }; 107 108 static int attached = 0; 109 110 static void 111 geode_wdog_disable(struct geode_wdog_softc *sc) 112 { 113 uint16_t wdcnfg; 114 115 /* cancel any pending countdown */ 116 sc->sc_countdown = 0; 117 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO, 0); 118 /* power-down clock */ 119 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 120 SC1100_GCB_WDCNFG); 121 122 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); 123 124 wdcnfg |= SC1100_WDCNFG_WD32KPD; 125 wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK); 126 /* This no-op is for the reader's benefit. */ 127 wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION | 128 SC1100_WDCNFG_WDTYPE2_NOACTION; 129 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg); 130 131 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); 132 } 133 134 static void 135 geode_wdog_enable(struct geode_wdog_softc *sc) 136 { 137 uint16_t wdcnfg; 138 139 /* power-up clock and set prescale */ 140 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG); 141 142 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); 143 144 wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK | 145 SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK); 146 wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK); 147 wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION; 148 149 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG, wdcnfg); 150 151 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); 152 } 153 154 static void 155 geode_wdog_reset(struct geode_wdog_softc *sc) 156 { 157 /* set countdown */ 158 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDTO, 159 sc->sc_countdown); 160 } 161 162 static int 163 geode_wdog_tickle(struct sysmon_wdog *smw) 164 { 165 int s; 166 struct geode_wdog_softc *sc = smw->smw_cookie; 167 168 s = splhigh(); 169 geode_wdog_reset(sc); 170 splx(s); 171 return 0; 172 } 173 174 static int 175 geode_wdog_setmode(struct sysmon_wdog *smw) 176 { 177 struct geode_wdog_softc *sc = smw->smw_cookie; 178 uint32_t ticks; 179 int prescale, s; 180 181 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 182 s = splhigh(); 183 geode_wdog_disable(sc); 184 splx(s); 185 return 0; 186 } 187 if (smw->smw_period == WDOG_PERIOD_DEFAULT) 188 smw->smw_period = 32; 189 else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */ 190 return EINVAL; 191 192 GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period)); 193 194 ticks = smw->smw_period * SC1100_WDCLK_HZ; 195 196 GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks)); 197 198 for (prescale = 0; ticks > UINT16_MAX; prescale++) 199 ticks /= 2; 200 201 GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks)); 202 GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale)); 203 204 KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX); 205 KASSERT(ticks <= UINT16_MAX); 206 207 s = splhigh(); 208 209 sc->sc_prescale = (uint8_t)prescale; 210 sc->sc_countdown = (uint16_t)ticks; 211 212 geode_wdog_enable(sc); 213 214 geode_wdog_reset(sc); 215 216 splx(s); 217 return 0; 218 } 219 220 static int 221 geode_wdog_match(struct device *parent, struct cfdata *match, 222 void *aux) 223 { 224 return !attached; 225 } 226 227 static void 228 geode_wdog_attach(struct device *parent, struct device *self, 229 void *aux) 230 { 231 struct geode_wdog_softc *sc = (void *) self; 232 uint8_t wdsts; 233 234 aprint_naive(": Watchdog Timer\n"); 235 aprint_normal(": AMD Geode SC1100 Watchdog Timer\n"); 236 237 238 /* 239 * Hook up the watchdog timer. 240 */ 241 sc->sc_gcb_dev = (struct geode_gcb_softc *)parent; 242 sc->sc_smw.smw_name = sc->sc_dev.dv_xname; 243 sc->sc_smw.smw_cookie = sc; 244 sc->sc_smw.smw_setmode = geode_wdog_setmode; 245 sc->sc_smw.smw_tickle = geode_wdog_tickle; 246 sc->sc_smw.smw_period = 32; 247 248 /* 249 * Determine cause of the last reset, and issue a warning if it 250 * was due to watchdog expiry. 251 */ 252 wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS); 253 254 GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", sc->sc_dev.dv_xname, 255 wdsts)); 256 257 if (wdsts & SC1100_WDSTS_WDRST) 258 aprint_error( 259 "%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n", 260 sc->sc_dev.dv_xname); 261 262 /* reset WDOVF by writing 1 to it */ 263 bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDSTS, 264 wdsts & SC1100_WDSTS_WDOVF); 265 266 if (sysmon_wdog_register(&sc->sc_smw) != 0) 267 aprint_error("%s: unable to register watchdog with sysmon\n", 268 sc->sc_dev.dv_xname); 269 270 /* cancel any pending countdown */ 271 geode_wdog_disable(sc); 272 273 attached = 1; 274 } 275 276 CFATTACH_DECL(geodewdog, sizeof(struct geode_wdog_softc), 277 geode_wdog_match, geode_wdog_attach, NULL, NULL); 278