xref: /freebsd/sys/dev/amdsbwd/amdsbwd.c (revision fe75646a0234a261c0013bf1840fdac4acaf0cec)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2009 Andriy Gapon <avg@FreeBSD.org>
5  * All rights reserved.
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  * This is a driver for watchdog timer present in AMD SB600/SB7xx/SB8xx
31  * southbridges.
32  * Please see the following specifications for the descriptions of the
33  * registers and flags:
34  * - AMD SB600 Register Reference Guide, Public Version,  Rev. 3.03 (SB600 RRG)
35  *   http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/46155_sb600_rrg_pub_3.03.pdf
36  * - AMD SB700/710/750 Register Reference Guide (RRG)
37  *   http://developer.amd.com/assets/43009_sb7xx_rrg_pub_1.00.pdf
38  * - AMD SB700/710/750 Register Programming Requirements (RPR)
39  *   http://developer.amd.com/assets/42413_sb7xx_rpr_pub_1.00.pdf
40  * - AMD SB800-Series Southbridges Register Reference Guide (RRG)
41  *   http://support.amd.com/us/Embedded_TechDocs/45482.pdf
42  * Please see the following for Watchdog Resource Table specification:
43  * - Watchdog Timer Hardware Requirements for Windows Server 2003 (WDRT)
44  *   http://www.microsoft.com/whdc/system/sysinternals/watchdog.mspx
45  * AMD SB600/SB7xx/SB8xx watchdog hardware seems to conform to the above
46  * specifications, but the table hasn't been spotted in the wild yet.
47  */
48 
49 #include <sys/cdefs.h>
50 #include "opt_amdsbwd.h"
51 
52 #include <sys/param.h>
53 #include <sys/eventhandler.h>
54 #include <sys/kernel.h>
55 #include <sys/module.h>
56 #include <sys/systm.h>
57 #include <sys/sysctl.h>
58 #include <sys/bus.h>
59 #include <machine/bus.h>
60 #include <sys/rman.h>
61 #include <machine/cputypes.h>
62 #include <machine/md_var.h>
63 #include <machine/resource.h>
64 #include <sys/watchdog.h>
65 
66 #include <dev/pci/pcivar.h>
67 #include <dev/amdsbwd/amd_chipset.h>
68 #include <isa/isavar.h>
69 
70 /*
71  * Registers in the Watchdog IO space.
72  * See SB7xx RRG 2.3.4, WDRT.
73  */
74 #define	AMDSB_WD_CTRL			0x00
75 #define		AMDSB_WD_RUN		0x01
76 #define		AMDSB_WD_FIRED		0x02
77 #define		AMDSB_WD_SHUTDOWN	0x04
78 #define		AMDSB_WD_DISABLE	0x08
79 #define		AMDSB_WD_RESERVED	0x70
80 #define		AMDSB_WD_RELOAD		0x80
81 #define	AMDSB_WD_COUNT			0x04
82 #define		AMDSB_WD_COUNT_MASK	0xffff
83 #define	AMDSB_WDIO_REG_WIDTH		4
84 
85 #define	amdsbwd_verbose_printf(dev, ...)	\
86 	do {						\
87 		if (bootverbose)			\
88 			device_printf(dev, __VA_ARGS__);\
89 	} while (0)
90 
91 struct amdsbwd_softc {
92 	device_t		dev;
93 	eventhandler_tag	ev_tag;
94 	struct resource		*res_ctrl;
95 	struct resource		*res_count;
96 	int			rid_ctrl;
97 	int			rid_count;
98 	int			ms_per_tick;
99 	int			max_ticks;
100 	int			active;
101 	unsigned int		timeout;
102 };
103 
104 static void	amdsbwd_identify(driver_t *driver, device_t parent);
105 static int	amdsbwd_probe(device_t dev);
106 static int	amdsbwd_attach(device_t dev);
107 static int	amdsbwd_detach(device_t dev);
108 static int	amdsbwd_suspend(device_t dev);
109 static int	amdsbwd_resume(device_t dev);
110 
111 static device_method_t amdsbwd_methods[] = {
112 	DEVMETHOD(device_identify,	amdsbwd_identify),
113 	DEVMETHOD(device_probe,		amdsbwd_probe),
114 	DEVMETHOD(device_attach,	amdsbwd_attach),
115 	DEVMETHOD(device_detach,	amdsbwd_detach),
116 	DEVMETHOD(device_suspend,	amdsbwd_suspend),
117 	DEVMETHOD(device_resume,	amdsbwd_resume),
118 #if 0
119 	DEVMETHOD(device_shutdown,	amdsbwd_detach),
120 #endif
121 	DEVMETHOD_END
122 };
123 
124 static driver_t		amdsbwd_driver = {
125 	"amdsbwd",
126 	amdsbwd_methods,
127 	sizeof(struct amdsbwd_softc)
128 };
129 
130 DRIVER_MODULE(amdsbwd, isa, amdsbwd_driver, NULL, NULL);
131 
132 static uint8_t
133 pmio_read(struct resource *res, uint8_t reg)
134 {
135 	bus_write_1(res, 0, reg);	/* Index */
136 	return (bus_read_1(res, 1));	/* Data */
137 }
138 
139 static void
140 pmio_write(struct resource *res, uint8_t reg, uint8_t val)
141 {
142 	bus_write_1(res, 0, reg);	/* Index */
143 	bus_write_1(res, 1, val);	/* Data */
144 }
145 
146 static uint32_t
147 wdctrl_read(struct amdsbwd_softc *sc)
148 {
149 	return (bus_read_4(sc->res_ctrl, 0));
150 }
151 
152 static void
153 wdctrl_write(struct amdsbwd_softc *sc, uint32_t val)
154 {
155 	bus_write_4(sc->res_ctrl, 0, val);
156 }
157 
158 static __unused uint32_t
159 wdcount_read(struct amdsbwd_softc *sc)
160 {
161 	return (bus_read_4(sc->res_count, 0));
162 }
163 
164 static void
165 wdcount_write(struct amdsbwd_softc *sc, uint32_t val)
166 {
167 	bus_write_4(sc->res_count, 0, val);
168 }
169 
170 static void
171 amdsbwd_tmr_enable(struct amdsbwd_softc *sc)
172 {
173 	uint32_t val;
174 
175 	val = wdctrl_read(sc);
176 	val |= AMDSB_WD_RUN;
177 	wdctrl_write(sc, val);
178 	sc->active = 1;
179 	amdsbwd_verbose_printf(sc->dev, "timer enabled\n");
180 }
181 
182 static void
183 amdsbwd_tmr_disable(struct amdsbwd_softc *sc)
184 {
185 	uint32_t val;
186 
187 	val = wdctrl_read(sc);
188 	val &= ~AMDSB_WD_RUN;
189 	wdctrl_write(sc, val);
190 	sc->active = 0;
191 	amdsbwd_verbose_printf(sc->dev, "timer disabled\n");
192 }
193 
194 static void
195 amdsbwd_tmr_reload(struct amdsbwd_softc *sc)
196 {
197 	uint32_t val;
198 
199 	val = wdctrl_read(sc);
200 	val |= AMDSB_WD_RELOAD;
201 	wdctrl_write(sc, val);
202 }
203 
204 static void
205 amdsbwd_tmr_set(struct amdsbwd_softc *sc, uint16_t timeout)
206 {
207 
208 	timeout &= AMDSB_WD_COUNT_MASK;
209 	wdcount_write(sc, timeout);
210 	sc->timeout = timeout;
211 	amdsbwd_verbose_printf(sc->dev, "timeout set to %u ticks\n", timeout);
212 }
213 
214 static void
215 amdsbwd_event(void *arg, unsigned int cmd, int *error)
216 {
217 	struct amdsbwd_softc *sc = arg;
218 	uint64_t timeout;
219 
220 	if (cmd != 0) {
221 		timeout = 0;
222 		cmd &= WD_INTERVAL;
223 		if (cmd >= WD_TO_1MS) {
224 			timeout = (uint64_t)1 << (cmd - WD_TO_1MS);
225 			timeout = timeout / sc->ms_per_tick;
226 		}
227 		/* For a too short timeout use 1 tick. */
228 		if (timeout == 0)
229 			timeout = 1;
230 		/* For a too long timeout stop the timer. */
231 		if (timeout > sc->max_ticks)
232 			timeout = 0;
233 	} else {
234 		timeout = 0;
235 	}
236 
237 	if (timeout != 0) {
238 		if (timeout != sc->timeout)
239 			amdsbwd_tmr_set(sc, timeout);
240 		if (!sc->active)
241 			amdsbwd_tmr_enable(sc);
242 		amdsbwd_tmr_reload(sc);
243 		*error = 0;
244 	} else {
245 		if (sc->active)
246 			amdsbwd_tmr_disable(sc);
247 	}
248 }
249 
250 static void
251 amdsbwd_identify(driver_t *driver, device_t parent)
252 {
253 	device_t		child;
254 	device_t		smb_dev;
255 
256 	if (resource_disabled("amdsbwd", 0))
257 		return;
258 	if (device_find_child(parent, "amdsbwd", -1) != NULL)
259 		return;
260 
261 	/*
262 	 * Try to identify SB600/SB7xx by PCI Device ID of SMBus device
263 	 * that should be present at bus 0, device 20, function 0.
264 	 */
265 	smb_dev = pci_find_bsf(0, 20, 0);
266 	if (smb_dev == NULL)
267 		return;
268 	if (pci_get_devid(smb_dev) != AMDSB_SMBUS_DEVID &&
269 	    pci_get_devid(smb_dev) != AMDFCH_SMBUS_DEVID &&
270 	    pci_get_devid(smb_dev) != AMDCZ_SMBUS_DEVID &&
271 	    pci_get_devid(smb_dev) != HYGONCZ_SMBUS_DEVID)
272 		return;
273 
274 	child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "amdsbwd", -1);
275 	if (child == NULL)
276 		device_printf(parent, "add amdsbwd child failed\n");
277 }
278 
279 static void
280 amdsbwd_probe_sb7xx(device_t dev, struct resource *pmres, uint32_t *addr)
281 {
282 	uint8_t	val;
283 	int	i;
284 
285 	/* Report cause of previous reset for user's convenience. */
286 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS0);
287 	if (val != 0)
288 		amdsbwd_verbose_printf(dev, "ResetStatus0 = %#04x\n", val);
289 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS1);
290 	if (val != 0)
291 		amdsbwd_verbose_printf(dev, "ResetStatus1 = %#04x\n", val);
292 	if ((val & AMDSB_WD_RST_STS) != 0)
293 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
294 
295 	/* Find base address of memory mapped WDT registers. */
296 	for (*addr = 0, i = 0; i < 4; i++) {
297 		*addr <<= 8;
298 		*addr |= pmio_read(pmres, AMDSB_PM_WDT_BASE_MSB - i);
299 	}
300 	*addr &= ~0x07u;
301 
302 	/* Set watchdog timer tick to 1s. */
303 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
304 	val &= ~AMDSB_WDT_RES_MASK;
305 	val |= AMDSB_WDT_RES_1S;
306 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
307 
308 	/* Enable watchdog device (in stopped state). */
309 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
310 	val &= ~AMDSB_WDT_DISABLE;
311 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
312 
313 	/*
314 	 * XXX TODO: Ensure that watchdog decode is enabled
315 	 * (register 0x41, bit 3).
316 	 */
317 	device_set_desc(dev, "AMD SB600/SB7xx Watchdog Timer");
318 }
319 
320 static void
321 amdsbwd_probe_sb8xx(device_t dev, struct resource *pmres, uint32_t *addr)
322 {
323 	uint32_t	val;
324 	int		i;
325 
326 	/* Report cause of previous reset for user's convenience. */
327 
328 	val = pmio_read(pmres, AMDSB8_PM_RESET_CTRL);
329 	if ((val & AMDSB8_RST_STS_DIS) != 0) {
330 		val &= ~AMDSB8_RST_STS_DIS;
331 		pmio_write(pmres, AMDSB8_PM_RESET_CTRL, val);
332 	}
333 	val = 0;
334 	for (i = 3; i >= 0; i--) {
335 		val <<= 8;
336 		val |= pmio_read(pmres, AMDSB8_PM_RESET_STATUS + i);
337 	}
338 	if (val != 0)
339 		amdsbwd_verbose_printf(dev, "ResetStatus = 0x%08x\n", val);
340 	if ((val & AMDSB8_WD_RST_STS) != 0)
341 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
342 
343 	/* Find base address of memory mapped WDT registers. */
344 	for (*addr = 0, i = 0; i < 4; i++) {
345 		*addr <<= 8;
346 		*addr |= pmio_read(pmres, AMDSB8_PM_WDT_EN + 3 - i);
347 	}
348 	*addr &= ~0x07u;
349 
350 	/* Set watchdog timer tick to 1s. */
351 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
352 	val &= ~AMDSB8_WDT_RES_MASK;
353 	val |= AMDSB8_WDT_1HZ;
354 	pmio_write(pmres, AMDSB8_PM_WDT_CTRL, val);
355 #ifdef AMDSBWD_DEBUG
356 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
357 	amdsbwd_verbose_printf(dev, "AMDSB8_PM_WDT_CTRL value = %#04x\n", val);
358 #endif
359 
360 	/*
361 	 * Enable watchdog device (in stopped state)
362 	 * and decoding of its address.
363 	 */
364 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
365 	val &= ~AMDSB8_WDT_DISABLE;
366 	val |= AMDSB8_WDT_DEC_EN;
367 	pmio_write(pmres, AMDSB8_PM_WDT_EN, val);
368 #ifdef AMDSBWD_DEBUG
369 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
370 	device_printf(dev, "AMDSB8_PM_WDT_EN value = %#04x\n", val);
371 #endif
372 	device_set_desc(dev, "AMD SB8xx/SB9xx/Axx Watchdog Timer");
373 }
374 
375 static void
376 amdsbwd_probe_fch41(device_t dev, struct resource *pmres, uint32_t *addr)
377 {
378 	uint8_t	val;
379 	char buf[36];
380 
381 	/*
382 	 * Enable decoding of watchdog MMIO address.
383 	 */
384 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN0);
385 	val |= AMDFCH41_WDT_EN;
386 	pmio_write(pmres, AMDFCH41_PM_DECODE_EN0, val);
387 #ifdef AMDSBWD_DEBUG
388 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN0);
389 	device_printf(dev, "AMDFCH41_PM_DECODE_EN0 value = %#04x\n", val);
390 #endif
391 
392 	val = pmio_read(pmres, AMDFCH41_PM_ISA_CTRL);
393 	if ((val & AMDFCH41_MMIO_EN) != 0) {
394 		/* Fixed offset for the watchdog within ACPI MMIO range. */
395 		amdsbwd_verbose_printf(dev, "ACPI MMIO range is enabled\n");
396 		*addr = AMDFCH41_MMIO_ADDR + AMDFCH41_MMIO_WDT_OFF;
397 	} else {
398 		/* Special fixed MMIO range for the watchdog. */
399 		*addr = AMDFCH41_WDT_FIXED_ADDR;
400 	}
401 
402 	/*
403 	 * Set watchdog timer tick to 1s and
404 	 * enable the watchdog device (in stopped state).
405 	 */
406 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN3);
407 	val &= ~AMDFCH41_WDT_RES_MASK;
408 	val |= AMDFCH41_WDT_RES_1S;
409 	val &= ~AMDFCH41_WDT_EN_MASK;
410 	val |= AMDFCH41_WDT_ENABLE;
411 	pmio_write(pmres, AMDFCH41_PM_DECODE_EN3, val);
412 #ifdef AMDSBWD_DEBUG
413 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN3);
414 	amdsbwd_verbose_printf(dev, "AMDFCH41_PM_DECODE_EN3 value = %#04x\n",
415 	    val);
416 #endif
417 	snprintf(buf, sizeof(buf), "%s FCH Rev 41h+ Watchdog Timer",
418 	    cpu_vendor_id == CPU_VENDOR_HYGON ? "Hygon" : "AMD");
419 	device_set_desc_copy(dev, buf);
420 }
421 
422 static int
423 amdsbwd_probe(device_t dev)
424 {
425 	struct resource		*res;
426 	device_t		smb_dev;
427 	uint32_t		addr;
428 	int			rid;
429 	int			rc;
430 	uint32_t		devid;
431 	uint8_t			revid;
432 
433 	/* Do not claim some ISA PnP device by accident. */
434 	if (isa_get_logicalid(dev) != 0)
435 		return (ENXIO);
436 
437 	rc = bus_set_resource(dev, SYS_RES_IOPORT, 0, AMDSB_PMIO_INDEX,
438 	    AMDSB_PMIO_WIDTH);
439 	if (rc != 0) {
440 		device_printf(dev, "bus_set_resource for IO failed\n");
441 		return (ENXIO);
442 	}
443 	rid = 0;
444 	res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
445 	    RF_ACTIVE | RF_SHAREABLE);
446 	if (res == NULL) {
447 		device_printf(dev, "bus_alloc_resource for IO failed\n");
448 		return (ENXIO);
449 	}
450 
451 	smb_dev = pci_find_bsf(0, 20, 0);
452 	KASSERT(smb_dev != NULL, ("can't find SMBus PCI device\n"));
453 	devid = pci_get_devid(smb_dev);
454 	revid = pci_get_revid(smb_dev);
455 	if (devid == AMDSB_SMBUS_DEVID && revid < AMDSB8_SMBUS_REVID)
456 		amdsbwd_probe_sb7xx(dev, res, &addr);
457 	else if (devid == AMDSB_SMBUS_DEVID ||
458 	    (devid == AMDFCH_SMBUS_DEVID && revid < AMDFCH41_SMBUS_REVID) ||
459 	    (devid == AMDCZ_SMBUS_DEVID  && revid < AMDCZ49_SMBUS_REVID))
460 		amdsbwd_probe_sb8xx(dev, res, &addr);
461 	else
462 		amdsbwd_probe_fch41(dev, res, &addr);
463 
464 	bus_release_resource(dev, SYS_RES_IOPORT, rid, res);
465 	bus_delete_resource(dev, SYS_RES_IOPORT, rid);
466 
467 	amdsbwd_verbose_printf(dev, "memory base address = %#010x\n", addr);
468 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 0, addr + AMDSB_WD_CTRL,
469 	    AMDSB_WDIO_REG_WIDTH);
470 	if (rc != 0) {
471 		device_printf(dev, "bus_set_resource for control failed\n");
472 		return (ENXIO);
473 	}
474 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 1, addr + AMDSB_WD_COUNT,
475 	    AMDSB_WDIO_REG_WIDTH);
476 	if (rc != 0) {
477 		device_printf(dev, "bus_set_resource for count failed\n");
478 		return (ENXIO);
479 	}
480 
481 	return (0);
482 }
483 
484 static int
485 amdsbwd_attach_sb(device_t dev, struct amdsbwd_softc *sc)
486 {
487 
488 	sc->max_ticks = UINT16_MAX;
489 	sc->rid_ctrl = 0;
490 	sc->rid_count = 1;
491 
492 	sc->ms_per_tick = 1000;
493 
494 	sc->res_ctrl = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
495 	    &sc->rid_ctrl, RF_ACTIVE);
496 	if (sc->res_ctrl == NULL) {
497 		device_printf(dev, "bus_alloc_resource for ctrl failed\n");
498 		return (ENXIO);
499 	}
500 	sc->res_count = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
501 	    &sc->rid_count, RF_ACTIVE);
502 	if (sc->res_count == NULL) {
503 		device_printf(dev, "bus_alloc_resource for count failed\n");
504 		return (ENXIO);
505 	}
506 	return (0);
507 }
508 
509 static int
510 amdsbwd_attach(device_t dev)
511 {
512 	struct amdsbwd_softc	*sc;
513 	int			rc;
514 
515 	sc = device_get_softc(dev);
516 	sc->dev = dev;
517 
518 	rc = amdsbwd_attach_sb(dev, sc);
519 	if (rc != 0)
520 		goto fail;
521 
522 #ifdef AMDSBWD_DEBUG
523 	device_printf(dev, "wd ctrl = %#04x\n", wdctrl_read(sc));
524 	device_printf(dev, "wd count = %#04x\n", wdcount_read(sc));
525 #endif
526 
527 	/* Setup initial state of Watchdog Control. */
528 	wdctrl_write(sc, AMDSB_WD_FIRED);
529 
530 	if (wdctrl_read(sc) & AMDSB_WD_DISABLE) {
531 		device_printf(dev, "watchdog hardware is disabled\n");
532 		goto fail;
533 	}
534 
535 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, amdsbwd_event, sc,
536 	    EVENTHANDLER_PRI_ANY);
537 
538 	return (0);
539 
540 fail:
541 	amdsbwd_detach(dev);
542 	return (ENXIO);
543 }
544 
545 static int
546 amdsbwd_detach(device_t dev)
547 {
548 	struct amdsbwd_softc *sc;
549 
550 	sc = device_get_softc(dev);
551 	if (sc->ev_tag != NULL)
552 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
553 
554 	if (sc->active)
555 		amdsbwd_tmr_disable(sc);
556 
557 	if (sc->res_ctrl != NULL)
558 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_ctrl,
559 		    sc->res_ctrl);
560 
561 	if (sc->res_count != NULL)
562 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_count,
563 		    sc->res_count);
564 
565 	return (0);
566 }
567 
568 static int
569 amdsbwd_suspend(device_t dev)
570 {
571 	struct amdsbwd_softc *sc;
572 	uint32_t val;
573 
574 	sc = device_get_softc(dev);
575 	val = wdctrl_read(sc);
576 	val &= ~AMDSB_WD_RUN;
577 	wdctrl_write(sc, val);
578 	return (0);
579 }
580 
581 static int
582 amdsbwd_resume(device_t dev)
583 {
584 	struct amdsbwd_softc *sc;
585 
586 	sc = device_get_softc(dev);
587 	wdctrl_write(sc, AMDSB_WD_FIRED);
588 	if (sc->active) {
589 		amdsbwd_tmr_set(sc, sc->timeout);
590 		amdsbwd_tmr_enable(sc);
591 		amdsbwd_tmr_reload(sc);
592 	}
593 	return (0);
594 }
595