ichwd.c revision 130402
1/* 2 * Copyright (c) 2004 Texas A&M University 3 * All rights reserved. 4 * 5 * Developer: Wm. Daryl Hawkins 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29/* 30 * Intel ICH Watchdog Timer (WDT) driver 31 * 32 * Originally developed by Wm. Daryl Hawkins of Texas A&M 33 * Heavily modified by <des@FreeBSD.org> 34 * 35 * This is a tricky one. The ICH WDT can't be treated as a regular PCI 36 * device as it's actually an integrated function of the ICH LPC interface 37 * bridge. Detection is also awkward, because we can only infer the 38 * presence of the watchdog timer from the fact that the machine has an 39 * ICH chipset, or, on ACPI 2.x systems, by the presence of the 'WDDT' 40 * ACPI table (although this driver does not support the ACPI detection 41 * method). 42 * 43 * There is one slight problem on non-ACPI or ACPI 1.x systems: we have no 44 * way of knowing if the WDT is permanently disabled (either by the BIOS 45 * or in hardware). 46 * 47 * The WDT is programmed through I/O registers in the ACPI I/O space. 48 * Intel swears it's always at offset 0x60, so we use that. 49 * 50 * For details about the ICH WDT, see Intel Application Note AP-725 51 * (document no. 292273-001). The WDT is also described in the individual 52 * chipset datasheets, e.g. Intel82801EB ICH5 / 82801ER ICH5R Datasheet 53 * (document no. 252516-001) sections 9.10 and 9.11. 54 */ 55 56#include <sys/cdefs.h> 57__FBSDID("$FreeBSD: head/sys/dev/ichwd/ichwd.c 130402 2004-06-13 05:00:19Z jmg $"); 58 59#include <sys/param.h> 60#include <sys/kernel.h> 61#include <sys/module.h> 62#include <sys/systm.h> 63#include <sys/bus.h> 64#include <machine/bus.h> 65#include <sys/rman.h> 66#include <machine/resource.h> 67#include <sys/watchdog.h> 68 69#include <dev/pci/pcivar.h> 70 71#include <dev/ichwd/ichwd.h> 72 73static struct ichwd_device ichwd_devices[] = { 74 { VENDORID_INTEL, DEVICEID_82801AA, "Intel 82801AA watchdog timer" }, 75 { VENDORID_INTEL, DEVICEID_82801AB, "Intel 82801AB watchdog timer" }, 76 { VENDORID_INTEL, DEVICEID_82801BA, "Intel 82801BA watchdog timer" }, 77 { VENDORID_INTEL, DEVICEID_82801BAM, "Intel 82801BAM watchdog timer" }, 78 { VENDORID_INTEL, DEVICEID_82801CA, "Intel 82801CA watchdog timer" }, 79 { VENDORID_INTEL, DEVICEID_82801CAM, "Intel 82801CAM watchdog timer" }, 80 { VENDORID_INTEL, DEVICEID_82801DB, "Intel 82801DB watchdog timer" }, 81 { VENDORID_INTEL, DEVICEID_82801DBM, "Intel 82801DBM watchdog timer" }, 82 { VENDORID_INTEL, DEVICEID_82801E, "Intel 82801E watchdog timer" }, 83 { VENDORID_INTEL, DEVICEID_82801EBR, "Intel 82801EB/ER watchdog timer" }, 84 { 0, 0, NULL }, 85}; 86 87static devclass_t ichwd_devclass; 88 89#define ichwd_read_1(sc, off) \ 90 bus_space_read_1((sc)->smi_bst, (sc)->smi_bsh, (off)) 91#define ichwd_read_2(sc, off) \ 92 bus_space_read_2((sc)->smi_bst, (sc)->smi_bsh, (off)) 93#define ichwd_read_4(sc, off) \ 94 bus_space_read_4((sc)->smi_bst, (sc)->smi_bsh, (off)) 95 96#define ichwd_write_1(sc, off, val) \ 97 bus_space_write_1((sc)->smi_bst, (sc)->smi_bsh, (off), (val)) 98#define ichwd_write_2(sc, off, val) \ 99 bus_space_write_2((sc)->smi_bst, (sc)->smi_bsh, (off), (val)) 100#define ichwd_write_4(sc, off, val) \ 101 bus_space_write_4((sc)->smi_bst, (sc)->smi_bsh, (off), (val)) 102 103static __inline void 104ichwd_intr_enable(struct ichwd_softc *sc) 105{ 106 ichwd_write_4(sc, SMI_EN, ichwd_read_4(sc, SMI_EN) | SMI_TCO_EN); 107} 108 109static __inline void 110ichwd_intr_disable(struct ichwd_softc *sc) 111{ 112 ichwd_write_4(sc, SMI_EN, ichwd_read_4(sc, SMI_EN) & ~SMI_TCO_EN); 113} 114 115static __inline void 116ichwd_sts_reset(struct ichwd_softc *sc) 117{ 118 ichwd_write_2(sc, TCO1_STS, TCO_TIMEOUT); 119 ichwd_write_2(sc, TCO2_STS, TCO_BOOT_STS); 120 ichwd_write_2(sc, TCO2_STS, TCO_SECOND_TO_STS); 121} 122 123static __inline void 124ichwd_tmr_enable(struct ichwd_softc *sc) 125{ 126 uint16_t cnt; 127 128 cnt = ichwd_read_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE; 129 ichwd_write_2(sc, TCO1_CNT, cnt & ~TCO_TMR_HALT); 130 sc->active = 1; 131 if (bootverbose) 132 device_printf(sc->device, "timer enabled\n"); 133} 134 135static __inline void 136ichwd_tmr_disable(struct ichwd_softc *sc) 137{ 138 uint16_t cnt; 139 140 cnt = ichwd_read_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE; 141 ichwd_write_2(sc, TCO1_CNT, cnt | TCO_TMR_HALT); 142 sc->active = 0; 143 if (bootverbose) 144 device_printf(sc->device, "timer disabled\n"); 145} 146 147static __inline void 148ichwd_tmr_reload(struct ichwd_softc *sc) 149{ 150 ichwd_write_1(sc, TCO_RLD, 1); 151 if (bootverbose) 152 device_printf(sc->device, "timer reloaded\n"); 153} 154 155static __inline void 156ichwd_tmr_set(struct ichwd_softc *sc, uint8_t timeout) 157{ 158 ichwd_write_1(sc, TCO_TMR, timeout); 159 sc->timeout = timeout; 160 if (bootverbose) 161 device_printf(sc->device, "timeout set to %u ticks\n", timeout); 162} 163 164/* 165 * Watchdog event handler. 166 */ 167static void 168ichwd_event(void *arg, unsigned int cmd, int *error) 169{ 170 struct ichwd_softc *sc = arg; 171 unsigned int timeout; 172 173 cmd &= WD_INTERVAL; 174 175 /* disable / enable */ 176 if (cmd == 0) { 177 if (sc->active) 178 ichwd_tmr_disable(sc); 179 *error = 0; 180 return; 181 } 182 if (!sc->active) 183 ichwd_tmr_enable(sc); 184 185 /* convert from power-of-to-ns to WDT ticks */ 186 if (cmd >= 64) { 187 *error = EINVAL; 188 return; 189 } 190 timeout = ((uint64_t)1 << cmd) / ICHWD_TICK; 191 if (timeout < ICHWD_MIN_TIMEOUT || timeout > ICHWD_MAX_TIMEOUT) { 192 *error = EINVAL; 193 return; 194 } 195 196 /* set new initial value */ 197 if (timeout != sc->timeout) 198 ichwd_tmr_set(sc, timeout); 199 200 /* reload */ 201 ichwd_tmr_reload(sc); 202 203 *error = 0; 204 return; 205} 206 207static unsigned long pmbase; 208 209/* 210 * Look for an ICH LPC interface bridge. If one is found, register an 211 * ichwd device. There can be only one. 212 */ 213static void 214ichwd_identify(driver_t *driver, device_t parent) 215{ 216 struct ichwd_device *id; 217 device_t ich = NULL; 218 device_t dev; 219 220 /* look for an ICH LPC interface bridge */ 221 for (id = ichwd_devices; id->desc != NULL; ++id) 222 if ((ich = pci_find_device(id->vendor, id->device)) != NULL) 223 break; 224 if (ich == NULL) 225 return; 226 227 if (bootverbose) 228 printf("%s(): found ICH chipset: %s\n", __func__, id->desc); 229 230 /* get for ACPI base address */ 231 pmbase = pci_read_config(ich, ICH_PMBASE, 2) & ICH_PMBASE_MASK; 232 if (pmbase == 0) { 233 if (bootverbose) 234 printf("%s(): ICH PMBASE register is empty\n", 235 __func__); 236 return; 237 } 238 239 /* try to clear the NO_REBOOT bit */ 240 pci_write_config(ich, ICH_GEN_STA, 0x00, 1); 241 if (pci_read_config(ich, ICH_GEN_STA, 1) & ICH_GEN_STA_NO_REBOOT) { 242 if (bootverbose) 243 printf("%s(): ICH WDT present but disabled\n", 244 __func__); 245 return; 246 } 247 248 /* good, add child to bus */ 249 if ((dev = device_find_child(parent, driver->name, 0)) == NULL) 250 dev = BUS_ADD_CHILD(parent, 0, driver->name, 0); 251 252 if (dev != NULL) 253 device_set_desc_copy(dev, id->desc); 254} 255 256static int 257ichwd_probe(device_t dev) 258{ 259 (void)dev; 260 return (0); 261} 262 263static int 264ichwd_attach(device_t dev) 265{ 266 struct ichwd_softc *sc; 267 268 sc = device_get_softc(dev); 269 sc->device = dev; 270 271 /* allocate I/O register space */ 272 sc->smi_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->smi_rid, 273 pmbase + SMI_BASE, pmbase + SMI_BASE + SMI_LEN - 1, SMI_LEN, 274 RF_ACTIVE|RF_SHAREABLE); 275 if (sc->smi_res == NULL) { 276 device_printf(dev, "unable to reserve SMI registers\n"); 277 goto fail; 278 } 279 sc->smi_bst = rman_get_bustag(sc->smi_res); 280 sc->smi_bsh = rman_get_bushandle(sc->smi_res); 281 sc->tco_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->tco_rid, 282 pmbase + TCO_BASE, pmbase + TCO_BASE + TCO_LEN - 1, TCO_LEN, 283 RF_ACTIVE|RF_SHAREABLE); 284 if (sc->tco_res == NULL) { 285 device_printf(dev, "unable to reserve TCO registers\n"); 286 goto fail; 287 } 288 sc->tco_bst = rman_get_bustag(sc->tco_res); 289 sc->tco_bsh = rman_get_bushandle(sc->tco_res); 290 291 /* reset the watchdog status registers */ 292 ichwd_sts_reset(sc); 293 294 /* make sure the WDT starts out inactive */ 295 ichwd_tmr_disable(sc); 296 297 /* register the watchdog event handler */ 298 sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0); 299 300 /* enable watchdog timeout interrupts */ 301 ichwd_intr_enable(sc); 302 303 return (0); 304 fail: 305 sc = device_get_softc(dev); 306 if (sc->tco_res != NULL) 307 bus_release_resource(dev, SYS_RES_IOPORT, 308 sc->tco_rid, sc->tco_res); 309 if (sc->smi_res != NULL) 310 bus_release_resource(dev, SYS_RES_IOPORT, 311 sc->smi_rid, sc->smi_res); 312 return (ENXIO); 313} 314 315static int 316ichwd_detach(device_t dev) 317{ 318 struct ichwd_softc *sc; 319 320 device_printf(dev, "detaching\n"); 321 322 sc = device_get_softc(dev); 323 324 /* halt the watchdog timer */ 325 if (sc->active) 326 ichwd_tmr_disable(sc); 327 328 /* disable watchdog timeout interrupts */ 329 ichwd_intr_disable(sc); 330 331 /* deregister event handler */ 332 if (sc->ev_tag != NULL) 333 EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag); 334 sc->ev_tag = NULL; 335 336 /* reset the watchdog status registers */ 337 ichwd_sts_reset(sc); 338 339 /* deallocate I/O register space */ 340 bus_release_resource(dev, SYS_RES_IOPORT, sc->tco_rid, sc->tco_res); 341 bus_release_resource(dev, SYS_RES_IOPORT, sc->smi_rid, sc->smi_res); 342 343 return (0); 344} 345 346static device_method_t ichwd_methods[] = { 347 DEVMETHOD(device_identify, ichwd_identify), 348 DEVMETHOD(device_probe, ichwd_probe), 349 DEVMETHOD(device_attach, ichwd_attach), 350 DEVMETHOD(device_detach, ichwd_detach), 351 {0,0} 352}; 353 354static driver_t ichwd_driver = { 355 "ichwd", 356 ichwd_methods, 357 sizeof(struct ichwd_softc), 358}; 359 360static int 361ichwd_modevent(module_t mode, int type, void *data) 362{ 363 int error = 0; 364 365 switch (type) { 366 case MOD_LOAD: 367 printf("ichwd module loaded\n"); 368 break; 369 case MOD_UNLOAD: 370 printf("ichwd module unloaded\n"); 371 break; 372 case MOD_SHUTDOWN: 373 printf("ichwd module shutting down\n"); 374 break; 375 } 376 return (error); 377} 378 379DRIVER_MODULE(ichwd, nexus, ichwd_driver, ichwd_devclass, ichwd_modevent, NULL); 380/* 381 * this doesn't seem to work, though I can't figure out why. 382 * currently not a big issue since watchdog is standard. 383MODULE_DEPEND(ichwd, watchdog, 1, 1, 1); 384 */ 385