xref: /freebsd/sys/dev/ichwd/ichwd.c (revision 0f2bd1e89db1a2f09268edea21e0ead329e092df)
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  * ICH6/7/8 support by Takeharu KATO <takeharu1219@ybb.ne.jp>
56  */
57 
58 #include <sys/cdefs.h>
59 __FBSDID("$FreeBSD$");
60 
61 #include <sys/param.h>
62 #include <sys/kernel.h>
63 #include <sys/module.h>
64 #include <sys/systm.h>
65 #include <sys/bus.h>
66 #include <machine/bus.h>
67 #include <sys/rman.h>
68 #include <machine/resource.h>
69 #include <sys/watchdog.h>
70 
71 #include <isa/isavar.h>
72 #include <dev/pci/pcivar.h>
73 
74 #include <dev/ichwd/ichwd.h>
75 
76 static struct ichwd_device ichwd_devices[] = {
77 	{ DEVICEID_82801AA,  "Intel 82801AA watchdog timer",	1 },
78 	{ DEVICEID_82801AB,  "Intel 82801AB watchdog timer",	1 },
79 	{ DEVICEID_82801BA,  "Intel 82801BA watchdog timer",	2 },
80 	{ DEVICEID_82801BAM, "Intel 82801BAM watchdog timer",	2 },
81 	{ DEVICEID_82801CA,  "Intel 82801CA watchdog timer",	3 },
82 	{ DEVICEID_82801CAM, "Intel 82801CAM watchdog timer",	3 },
83 	{ DEVICEID_82801DB,  "Intel 82801DB watchdog timer",	4 },
84 	{ DEVICEID_82801DBM, "Intel 82801DBM watchdog timer",	4 },
85 	{ DEVICEID_82801E,   "Intel 82801E watchdog timer",	5 },
86 	{ DEVICEID_82801EB,  "Intel 82801EB watchdog timer",	5 },
87 	{ DEVICEID_82801EBR, "Intel 82801EB/ER watchdog timer",	5 },
88 	{ DEVICEID_6300ESB,  "Intel 6300ESB watchdog timer",	5 },
89 	{ DEVICEID_82801FBR, "Intel 82801FB/FR watchdog timer",	6 },
90 	{ DEVICEID_ICH6M,    "Intel ICH6M watchdog timer",	6 },
91 	{ DEVICEID_ICH6W,    "Intel ICH6W watchdog timer",	6 },
92 	{ DEVICEID_ICH7,     "Intel ICH7 watchdog timer",	7 },
93 	{ DEVICEID_ICH7DH,   "Intel ICH7DH watchdog timer",	7 },
94 	{ DEVICEID_ICH7M,    "Intel ICH7M watchdog timer",	7 },
95 	{ DEVICEID_ICH7MDH,  "Intel ICH7MDH watchdog timer",	7 },
96 	{ DEVICEID_NM10,     "Intel NM10 watchdog timer",	7 },
97 	{ DEVICEID_ICH8,     "Intel ICH8 watchdog timer",	8 },
98 	{ DEVICEID_ICH8DH,   "Intel ICH8DH watchdog timer",	8 },
99 	{ DEVICEID_ICH8DO,   "Intel ICH8DO watchdog timer",	8 },
100 	{ DEVICEID_ICH8M,    "Intel ICH8M watchdog timer",	8 },
101 	{ DEVICEID_ICH8ME,   "Intel ICH8M-E watchdog timer",	8 },
102 	{ DEVICEID_63XXESB,  "Intel 63XXESB watchdog timer",	8 },
103 	{ DEVICEID_ICH9,     "Intel ICH9 watchdog timer",	9 },
104 	{ DEVICEID_ICH9DH,   "Intel ICH9DH watchdog timer",	9 },
105 	{ DEVICEID_ICH9DO,   "Intel ICH9DO watchdog timer",	9 },
106 	{ DEVICEID_ICH9M,    "Intel ICH9M watchdog timer",	9 },
107 	{ DEVICEID_ICH9ME,   "Intel ICH9M-E watchdog timer",	9 },
108 	{ DEVICEID_ICH9R,    "Intel ICH9R watchdog timer",	9 },
109 	{ DEVICEID_ICH10,    "Intel ICH10 watchdog timer",	10 },
110 	{ DEVICEID_ICH10D,   "Intel ICH10D watchdog timer",	10 },
111 	{ DEVICEID_ICH10DO,  "Intel ICH10DO watchdog timer",	10 },
112 	{ DEVICEID_ICH10R,   "Intel ICH10R watchdog timer",	10 },
113 	{ DEVICEID_H55,      "Intel H55 watchdog timer",	10 },
114 	{ 0, NULL, 0 },
115 };
116 
117 static devclass_t ichwd_devclass;
118 
119 #define ichwd_read_tco_1(sc, off) \
120 	bus_space_read_1((sc)->tco_bst, (sc)->tco_bsh, (off))
121 #define ichwd_read_tco_2(sc, off) \
122 	bus_space_read_2((sc)->tco_bst, (sc)->tco_bsh, (off))
123 #define ichwd_read_tco_4(sc, off) \
124 	bus_space_read_4((sc)->tco_bst, (sc)->tco_bsh, (off))
125 #define ichwd_read_smi_4(sc, off) \
126 	bus_space_read_4((sc)->smi_bst, (sc)->smi_bsh, (off))
127 #define ichwd_read_gcs_4(sc, off) \
128 	bus_space_read_4((sc)->gcs_bst, (sc)->gcs_bsh, (off))
129 
130 #define ichwd_write_tco_1(sc, off, val) \
131 	bus_space_write_1((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
132 #define ichwd_write_tco_2(sc, off, val) \
133 	bus_space_write_2((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
134 #define ichwd_write_tco_4(sc, off, val) \
135 	bus_space_write_4((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
136 #define ichwd_write_smi_4(sc, off, val) \
137 	bus_space_write_4((sc)->smi_bst, (sc)->smi_bsh, (off), (val))
138 #define ichwd_write_gcs_4(sc, off, val) \
139 	bus_space_write_4((sc)->gcs_bst, (sc)->gcs_bsh, (off), (val))
140 
141 #define ichwd_verbose_printf(dev, ...) \
142 	do {						\
143 		if (bootverbose)			\
144 			device_printf(dev, __VA_ARGS__);\
145 	} while (0)
146 
147 /*
148  * Disable the watchdog timeout SMI handler.
149  *
150  * Apparently, some BIOSes install handlers that reset or disable the
151  * watchdog timer instead of resetting the system, so we disable the SMI
152  * (by clearing the SMI_TCO_EN bit of the SMI_EN register) to prevent this
153  * from happening.
154  */
155 static __inline void
156 ichwd_smi_disable(struct ichwd_softc *sc)
157 {
158 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) & ~SMI_TCO_EN);
159 }
160 
161 /*
162  * Enable the watchdog timeout SMI handler.  See above for details.
163  */
164 static __inline void
165 ichwd_smi_enable(struct ichwd_softc *sc)
166 {
167 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) | SMI_TCO_EN);
168 }
169 
170 /*
171  * Reset the watchdog status bits.
172  */
173 static __inline void
174 ichwd_sts_reset(struct ichwd_softc *sc)
175 {
176 	/*
177 	 * The watchdog status bits are set to 1 by the hardware to
178 	 * indicate various conditions.  They can be cleared by software
179 	 * by writing a 1, not a 0.
180 	 */
181 	ichwd_write_tco_2(sc, TCO1_STS, TCO_TIMEOUT);
182 	/*
183 	 * XXX The datasheet says that TCO_SECOND_TO_STS must be cleared
184 	 * before TCO_BOOT_STS, not the other way around.
185 	 */
186 	ichwd_write_tco_2(sc, TCO2_STS, TCO_BOOT_STS);
187 	ichwd_write_tco_2(sc, TCO2_STS, TCO_SECOND_TO_STS);
188 }
189 
190 /*
191  * Enable the watchdog timer by clearing the TCO_TMR_HALT bit in the
192  * TCO1_CNT register.  This is complicated by the need to preserve bit 9
193  * of that same register, and the requirement that all other bits must be
194  * written back as zero.
195  */
196 static __inline void
197 ichwd_tmr_enable(struct ichwd_softc *sc)
198 {
199 	uint16_t cnt;
200 
201 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
202 	ichwd_write_tco_2(sc, TCO1_CNT, cnt & ~TCO_TMR_HALT);
203 	sc->active = 1;
204 	ichwd_verbose_printf(sc->device, "timer enabled\n");
205 }
206 
207 /*
208  * Disable the watchdog timer.  See above for details.
209  */
210 static __inline void
211 ichwd_tmr_disable(struct ichwd_softc *sc)
212 {
213 	uint16_t cnt;
214 
215 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
216 	ichwd_write_tco_2(sc, TCO1_CNT, cnt | TCO_TMR_HALT);
217 	sc->active = 0;
218 	ichwd_verbose_printf(sc->device, "timer disabled\n");
219 }
220 
221 /*
222  * Reload the watchdog timer: writing anything to any of the lower five
223  * bits of the TCO_RLD register reloads the timer from the last value
224  * written to TCO_TMR.
225  */
226 static __inline void
227 ichwd_tmr_reload(struct ichwd_softc *sc)
228 {
229 	if (sc->ich_version <= 5)
230 		ichwd_write_tco_1(sc, TCO_RLD, 1);
231 	else
232 		ichwd_write_tco_2(sc, TCO_RLD, 1);
233 
234 	ichwd_verbose_printf(sc->device, "timer reloaded\n");
235 }
236 
237 /*
238  * Set the initial timeout value.  Note that this must always be followed
239  * by a reload.
240  */
241 static __inline void
242 ichwd_tmr_set(struct ichwd_softc *sc, unsigned int timeout)
243 {
244 
245 	/*
246 	 * If the datasheets are to be believed, the minimum value
247 	 * actually varies from chipset to chipset - 4 for ICH5 and 2 for
248 	 * all other chipsets.  I suspect this is a bug in the ICH5
249 	 * datasheet and that the minimum is uniformly 2, but I'd rather
250 	 * err on the side of caution.
251 	 */
252 	if (timeout < 4)
253 		timeout = 4;
254 
255 	if (sc->ich_version <= 5) {
256 		uint8_t tmr_val8 = ichwd_read_tco_1(sc, TCO_TMR1);
257 
258 		tmr_val8 &= 0xc0;
259 		if (timeout > 0x3f)
260 			timeout = 0x3f;
261 		tmr_val8 |= timeout;
262 		ichwd_write_tco_1(sc, TCO_TMR1, tmr_val8);
263 	} else {
264 		uint16_t tmr_val16 = ichwd_read_tco_2(sc, TCO_TMR2);
265 
266 		tmr_val16 &= 0xfc00;
267 		if (timeout > 0x03ff)
268 			timeout = 0x03ff;
269 		tmr_val16 |= timeout;
270 		ichwd_write_tco_2(sc, TCO_TMR2, tmr_val16);
271 	}
272 
273 	sc->timeout = timeout;
274 
275 	ichwd_verbose_printf(sc->device, "timeout set to %u ticks\n", timeout);
276 }
277 
278 static __inline int
279 ichwd_clear_noreboot(struct ichwd_softc *sc)
280 {
281 	uint32_t status;
282 	int rc = 0;
283 
284 	/* try to clear the NO_REBOOT bit */
285 	if (sc->ich_version <= 5) {
286 		status = pci_read_config(sc->ich, ICH_GEN_STA, 1);
287 		status &= ~ICH_GEN_STA_NO_REBOOT;
288 		pci_write_config(sc->ich, ICH_GEN_STA, status, 1);
289 		status = pci_read_config(sc->ich, ICH_GEN_STA, 1);
290 		if (status & ICH_GEN_STA_NO_REBOOT)
291 			rc = EIO;
292 	} else {
293 		status = ichwd_read_gcs_4(sc, 0);
294 		status &= ~ICH_GCS_NO_REBOOT;
295 		ichwd_write_gcs_4(sc, 0, status);
296 		status = ichwd_read_gcs_4(sc, 0);
297 		if (status & ICH_GCS_NO_REBOOT)
298 			rc = EIO;
299 	}
300 
301 	if (rc)
302 		device_printf(sc->device,
303 		    "ICH WDT present but disabled in BIOS or hardware\n");
304 
305 	return (rc);
306 }
307 
308 /*
309  * Watchdog event handler - called by the framework to enable or disable
310  * the watchdog or change the initial timeout value.
311  */
312 static void
313 ichwd_event(void *arg, unsigned int cmd, int *error)
314 {
315 	struct ichwd_softc *sc = arg;
316 	unsigned int timeout;
317 
318 	/* convert from power-of-two-ns to WDT ticks */
319 	cmd &= WD_INTERVAL;
320 	timeout = ((uint64_t)1 << cmd) / ICHWD_TICK;
321 	if (cmd) {
322 		if (timeout != sc->timeout) {
323 			if (!sc->active)
324 				ichwd_tmr_enable(sc);
325 			ichwd_tmr_set(sc, timeout);
326 		}
327 		ichwd_tmr_reload(sc);
328 		*error = 0;
329 	} else {
330 		if (sc->active)
331 			ichwd_tmr_disable(sc);
332 	}
333 }
334 
335 static device_t
336 ichwd_find_ich_lpc_bridge(struct ichwd_device **id_p)
337 {
338 	struct ichwd_device *id;
339 	device_t ich = NULL;
340 
341 	/* look for an ICH LPC interface bridge */
342 	for (id = ichwd_devices; id->desc != NULL; ++id)
343 		if ((ich = pci_find_device(VENDORID_INTEL, id->device)) != NULL)
344 			break;
345 
346 	if (ich == NULL)
347 		return (NULL);
348 
349 	ichwd_verbose_printf(ich, "found ICH%d or equivalent chipset: %s\n",
350 	    id->version, id->desc);
351 
352 	if (id_p)
353 		*id_p = id;
354 
355 	return (ich);
356 }
357 
358 /*
359  * Look for an ICH LPC interface bridge.  If one is found, register an
360  * ichwd device.  There can be only one.
361  */
362 static void
363 ichwd_identify(driver_t *driver, device_t parent)
364 {
365 	struct ichwd_device *id_p;
366 	device_t ich = NULL;
367 	device_t dev;
368 	uint32_t rcba;
369 	int rc;
370 
371 	ich = ichwd_find_ich_lpc_bridge(&id_p);
372 	if (ich == NULL)
373 		return;
374 
375 	/* good, add child to bus */
376 	if ((dev = device_find_child(parent, driver->name, 0)) == NULL)
377 		dev = BUS_ADD_CHILD(parent, 0, driver->name, 0);
378 
379 	if (dev == NULL)
380 		return;
381 
382 	device_set_desc_copy(dev, id_p->desc);
383 
384 	if (id_p->version >= 6) {
385 		/* get RCBA (root complex base address) */
386 		rcba = pci_read_config(ich, ICH_RCBA, 4);
387 		rc = bus_set_resource(ich, SYS_RES_MEMORY, 0,
388 		    (rcba & 0xffffc000) + ICH_GCS_OFFSET, ICH_GCS_SIZE);
389 		if (rc)
390 			ichwd_verbose_printf(dev,
391 			    "Can not set memory resource for RCBA\n");
392 	}
393 }
394 
395 static int
396 ichwd_probe(device_t dev)
397 {
398 
399 	/* Do not claim some ISA PnP device by accident. */
400 	if (isa_get_logicalid(dev) != 0)
401 		return (ENXIO);
402 	return (0);
403 }
404 
405 static int
406 ichwd_attach(device_t dev)
407 {
408 	struct ichwd_softc *sc;
409 	struct ichwd_device *id_p;
410 	device_t ich;
411 	unsigned int pmbase = 0;
412 
413 	sc = device_get_softc(dev);
414 	sc->device = dev;
415 
416 	ich = ichwd_find_ich_lpc_bridge(&id_p);
417 	if (ich == NULL) {
418 		device_printf(sc->device, "Can not find ICH device.\n");
419 		goto fail;
420 	}
421 	sc->ich = ich;
422 	sc->ich_version = id_p->version;
423 
424 	/* get ACPI base address */
425 	pmbase = pci_read_config(ich, ICH_PMBASE, 2) & ICH_PMBASE_MASK;
426 	if (pmbase == 0) {
427 		device_printf(dev, "ICH PMBASE register is empty\n");
428 		goto fail;
429 	}
430 
431 	/* allocate I/O register space */
432 	sc->smi_rid = 0;
433 	sc->smi_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->smi_rid,
434 	    pmbase + SMI_BASE, pmbase + SMI_BASE + SMI_LEN - 1, SMI_LEN,
435 	    RF_ACTIVE | RF_SHAREABLE);
436 	if (sc->smi_res == NULL) {
437 		device_printf(dev, "unable to reserve SMI registers\n");
438 		goto fail;
439 	}
440 	sc->smi_bst = rman_get_bustag(sc->smi_res);
441 	sc->smi_bsh = rman_get_bushandle(sc->smi_res);
442 
443 	sc->tco_rid = 1;
444 	sc->tco_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->tco_rid,
445 	    pmbase + TCO_BASE, pmbase + TCO_BASE + TCO_LEN - 1, TCO_LEN,
446 	    RF_ACTIVE | RF_SHAREABLE);
447 	if (sc->tco_res == NULL) {
448 		device_printf(dev, "unable to reserve TCO registers\n");
449 		goto fail;
450 	}
451 	sc->tco_bst = rman_get_bustag(sc->tco_res);
452 	sc->tco_bsh = rman_get_bushandle(sc->tco_res);
453 
454 	sc->gcs_rid = 0;
455 	if (sc->ich_version >= 6) {
456 		sc->gcs_res = bus_alloc_resource_any(ich, SYS_RES_MEMORY,
457 		    &sc->gcs_rid, RF_ACTIVE|RF_SHAREABLE);
458 		if (sc->gcs_res == NULL) {
459 			device_printf(dev, "unable to reserve GCS registers\n");
460 			goto fail;
461 		}
462 		sc->gcs_bst = rman_get_bustag(sc->gcs_res);
463 		sc->gcs_bsh = rman_get_bushandle(sc->gcs_res);
464 	} else {
465 		sc->gcs_res = 0;
466 		sc->gcs_bst = 0;
467 		sc->gcs_bsh = 0;
468 	}
469 
470 	if (ichwd_clear_noreboot(sc) != 0)
471 		goto fail;
472 
473 	ichwd_verbose_printf(dev, "%s (ICH%d or equivalent)\n",
474 	    device_get_desc(dev), sc->ich_version);
475 
476 	/*
477 	 * XXX we should check the status registers (specifically, the
478 	 * TCO_SECOND_TO_STS bit in the TCO2_STS register) to see if we
479 	 * just came back from a watchdog-induced reset, and let the user
480 	 * know.
481 	 */
482 
483 	/* reset the watchdog status registers */
484 	ichwd_sts_reset(sc);
485 
486 	/* make sure the WDT starts out inactive */
487 	ichwd_tmr_disable(sc);
488 
489 	/* register the watchdog event handler */
490 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0);
491 
492 	/* disable the SMI handler */
493 	ichwd_smi_disable(sc);
494 
495 	return (0);
496  fail:
497 	sc = device_get_softc(dev);
498 	if (sc->tco_res != NULL)
499 		bus_release_resource(dev, SYS_RES_IOPORT,
500 		    sc->tco_rid, sc->tco_res);
501 	if (sc->smi_res != NULL)
502 		bus_release_resource(dev, SYS_RES_IOPORT,
503 		    sc->smi_rid, sc->smi_res);
504 	if (sc->gcs_res != NULL)
505 		bus_release_resource(ich, SYS_RES_MEMORY,
506 		    sc->gcs_rid, sc->gcs_res);
507 
508 	return (ENXIO);
509 }
510 
511 static int
512 ichwd_detach(device_t dev)
513 {
514 	struct ichwd_softc *sc;
515 	device_t ich = NULL;
516 
517 	sc = device_get_softc(dev);
518 
519 	/* halt the watchdog timer */
520 	if (sc->active)
521 		ichwd_tmr_disable(sc);
522 
523 	/* enable the SMI handler */
524 	ichwd_smi_enable(sc);
525 
526 	/* deregister event handler */
527 	if (sc->ev_tag != NULL)
528 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
529 	sc->ev_tag = NULL;
530 
531 	/* reset the watchdog status registers */
532 	ichwd_sts_reset(sc);
533 
534 	/* deallocate I/O register space */
535 	bus_release_resource(dev, SYS_RES_IOPORT, sc->tco_rid, sc->tco_res);
536 	bus_release_resource(dev, SYS_RES_IOPORT, sc->smi_rid, sc->smi_res);
537 
538 	/* deallocate memory resource */
539 	ich = ichwd_find_ich_lpc_bridge(NULL);
540 	if (sc->gcs_res && ich)
541 		bus_release_resource(ich, SYS_RES_MEMORY, sc->gcs_rid, sc->gcs_res);
542 
543 	return (0);
544 }
545 
546 static device_method_t ichwd_methods[] = {
547 	DEVMETHOD(device_identify, ichwd_identify),
548 	DEVMETHOD(device_probe,	ichwd_probe),
549 	DEVMETHOD(device_attach, ichwd_attach),
550 	DEVMETHOD(device_detach, ichwd_detach),
551 	DEVMETHOD(device_shutdown, ichwd_detach),
552 	{0,0}
553 };
554 
555 static driver_t ichwd_driver = {
556 	"ichwd",
557 	ichwd_methods,
558 	sizeof(struct ichwd_softc),
559 };
560 
561 DRIVER_MODULE(ichwd, isa, ichwd_driver, ichwd_devclass, NULL, NULL);
562