geodewdg.c revision 1.8
1 /* $NetBSD: geodewdg.c,v 1.8 2008/04/28 20:23:25 martin 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 * 52 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 53 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 54 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 55 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 56 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 57 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 58 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 59 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 60 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 61 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 62 * POSSIBILITY OF SUCH DAMAGE. 63 */ 64 65 /* 66 * Device driver for the watchdog timer built into the 67 * AMD Geode SC1100 processor. 68 */ 69 70 #include <sys/cdefs.h> 71 72 __KERNEL_RCSID(0, "$NetBSD: geodewdg.c,v 1.8 2008/04/28 20:23:25 martin Exp $"); 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/device.h> 77 #include <sys/wdog.h> 78 #include <uvm/uvm_extern.h> 79 #include <machine/bus.h> 80 #include <dev/pci/pcivar.h> 81 #include <dev/pci/pcidevs.h> 82 #include <arch/i386/pci/geodevar.h> 83 #include <arch/i386/pci/geodereg.h> 84 #include <dev/sysmon/sysmonvar.h> 85 86 #ifdef GEODE_DEBUG 87 #define GEODE_DPRINTF(__x) printf __x 88 #else /* GEODE_DEBUG */ 89 #define GEODE_DPRINTF(__x) /* nothing */ 90 #endif 91 92 struct geode_wdog_softc { 93 struct device sc_dev; 94 struct geode_gcb_softc *sc_gcb_dev; 95 96 uint16_t sc_countdown; 97 uint8_t sc_prescale; 98 struct sysmon_wdog sc_smw; 99 }; 100 101 static int attached = 0; 102 103 static void 104 geode_wdog_disable(struct geode_wdog_softc *sc) 105 { 106 uint16_t wdcnfg; 107 108 /* cancel any pending countdown */ 109 sc->sc_countdown = 0; 110 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 111 SC1100_GCB_WDTO, 0); 112 /* power-down clock */ 113 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, 114 sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG); 115 116 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); 117 118 wdcnfg |= SC1100_WDCNFG_WD32KPD; 119 wdcnfg &= ~(SC1100_WDCNFG_WDTYPE2_MASK | SC1100_WDCNFG_WDTYPE1_MASK); 120 /* This no-op is for the reader's benefit. */ 121 wdcnfg |= SC1100_WDCNFG_WDTYPE1_NOACTION | 122 SC1100_WDCNFG_WDTYPE2_NOACTION; 123 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 124 SC1100_GCB_WDCNFG, wdcnfg); 125 126 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); 127 } 128 129 static void 130 geode_wdog_enable(struct geode_wdog_softc *sc) 131 { 132 uint16_t wdcnfg; 133 134 /* power-up clock and set prescale */ 135 wdcnfg = bus_space_read_2(sc->sc_gcb_dev->sc_iot, 136 sc->sc_gcb_dev->sc_ioh, SC1100_GCB_WDCNFG); 137 138 GEODE_DPRINTF(("%s: wdcnfg %#04" PRIx16 " -> ", __func__, wdcnfg)); 139 140 wdcnfg &= ~(SC1100_WDCNFG_WD32KPD | SC1100_WDCNFG_WDPRES_MASK | 141 SC1100_WDCNFG_WDTYPE1_MASK | SC1100_WDCNFG_WDTYPE2_MASK); 142 wdcnfg |= __SHIFTIN(sc->sc_prescale, SC1100_WDCNFG_WDPRES_MASK); 143 wdcnfg |= SC1100_WDCNFG_WDTYPE1_RESET | SC1100_WDCNFG_WDTYPE2_NOACTION; 144 145 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 146 SC1100_GCB_WDCNFG, wdcnfg); 147 148 GEODE_DPRINTF(("%#04" PRIx16 "\n", wdcnfg)); 149 } 150 151 static void 152 geode_wdog_reset(struct geode_wdog_softc *sc) 153 { 154 /* set countdown */ 155 bus_space_write_2(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 156 SC1100_GCB_WDTO, sc->sc_countdown); 157 } 158 159 static int 160 geode_wdog_tickle(struct sysmon_wdog *smw) 161 { 162 int s; 163 struct geode_wdog_softc *sc = smw->smw_cookie; 164 165 s = splhigh(); 166 geode_wdog_reset(sc); 167 splx(s); 168 return 0; 169 } 170 171 static int 172 geode_wdog_setmode(struct sysmon_wdog *smw) 173 { 174 struct geode_wdog_softc *sc = smw->smw_cookie; 175 uint32_t ticks; 176 int prescale, s; 177 178 if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) { 179 s = splhigh(); 180 geode_wdog_disable(sc); 181 splx(s); 182 return 0; 183 } 184 if (smw->smw_period == WDOG_PERIOD_DEFAULT) 185 smw->smw_period = 32; 186 else if (smw->smw_period > SC1100_WDIVL_MAX) /* too big? */ 187 return EINVAL; 188 189 GEODE_DPRINTF(("%s: period %u\n", __func__, smw->smw_period)); 190 191 ticks = smw->smw_period * SC1100_WDCLK_HZ; 192 193 GEODE_DPRINTF(("%s: ticks0 %" PRIu32 "\n", __func__, ticks)); 194 195 for (prescale = 0; ticks > UINT16_MAX; prescale++) 196 ticks /= 2; 197 198 GEODE_DPRINTF(("%s: ticks %" PRIu32 "\n", __func__, ticks)); 199 GEODE_DPRINTF(("%s: prescale %d\n", __func__, prescale)); 200 201 KASSERT(prescale <= SC1100_WDCNFG_WDPRES_MAX); 202 KASSERT(ticks <= UINT16_MAX); 203 204 s = splhigh(); 205 206 sc->sc_prescale = (uint8_t)prescale; 207 sc->sc_countdown = (uint16_t)ticks; 208 209 geode_wdog_enable(sc); 210 211 geode_wdog_reset(sc); 212 213 splx(s); 214 return 0; 215 } 216 217 static int 218 geode_wdog_match(device_t parent, struct cfdata *match, void *aux) 219 { 220 return !attached; 221 } 222 223 static void 224 geode_wdog_attach(device_t parent, device_t self, void *aux) 225 { 226 struct geode_wdog_softc *sc = device_private(self); 227 uint8_t wdsts; 228 229 aprint_naive(": Watchdog Timer\n"); 230 aprint_normal(": AMD Geode SC1100 Watchdog Timer\n"); 231 232 233 /* 234 * Hook up the watchdog timer. 235 */ 236 sc->sc_gcb_dev = device_private(parent); 237 sc->sc_smw.smw_name = device_xname(self); 238 sc->sc_smw.smw_cookie = sc; 239 sc->sc_smw.smw_setmode = geode_wdog_setmode; 240 sc->sc_smw.smw_tickle = geode_wdog_tickle; 241 sc->sc_smw.smw_period = 32; 242 243 /* 244 * Determine cause of the last reset, and issue a warning if it 245 * was due to watchdog expiry. 246 */ 247 wdsts = bus_space_read_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 248 SC1100_GCB_WDSTS); 249 250 GEODE_DPRINTF(("%s: status %#02" PRIx8 "\n", device_xname(self), 251 wdsts)); 252 253 if (wdsts & SC1100_WDSTS_WDRST) 254 aprint_error( 255 "%s: WARNING: LAST RESET DUE TO WATCHDOG EXPIRATION!\n", 256 device_xname(self)); 257 258 /* reset WDOVF by writing 1 to it */ 259 bus_space_write_1(sc->sc_gcb_dev->sc_iot, sc->sc_gcb_dev->sc_ioh, 260 SC1100_GCB_WDSTS, wdsts & SC1100_WDSTS_WDOVF); 261 262 if (sysmon_wdog_register(&sc->sc_smw) != 0) 263 aprint_error("%s: unable to register watchdog with sysmon\n", 264 device_xname(self)); 265 266 /* cancel any pending countdown */ 267 geode_wdog_disable(sc); 268 269 attached = 1; 270 } 271 272 static int 273 geode_wdog_detach(device_t self, int flags) 274 { 275 int rc; 276 struct geode_wdog_softc *sc = device_private(self); 277 278 if ((rc = sysmon_wdog_unregister(&sc->sc_smw)) != 0) { 279 if (rc == ERESTART) 280 rc = EINTR; 281 return rc; 282 } 283 284 /* cancel any pending countdown */ 285 geode_wdog_disable(sc); 286 287 attached = 0; 288 289 return 0; 290 } 291 292 CFATTACH_DECL(geodewdog, sizeof(struct geode_wdog_softc), 293 geode_wdog_match, geode_wdog_attach, geode_wdog_detach, NULL); 294
Indexes created Thu Oct 23 22:10:10 GMT 2025