xref: /dragonfly/sys/dev/misc/amdsbwd/amdsbwd.c (revision 5fb3968e)
1 /*-
2  * Copyright (c) 2009 Andriy Gapon <avg@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * This is a driver for watchdog timer present in AMD SB600/SB7xx/SB8xx
29  * southbridges.
30  * Please see the following specifications for the descriptions of the
31  * registers and flags:
32  * - AMD SB600 Register Reference Guide, Public Version,  Rev. 3.03 (SB600 RRG)
33  *   http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/46155_sb600_rrg_pub_3.03.pdf
34  * - AMD SB700/710/750 Register Reference Guide (RRG)
35  *   http://developer.amd.com/assets/43009_sb7xx_rrg_pub_1.00.pdf
36  * - AMD SB700/710/750 Register Programming Requirements (RPR)
37  *   http://developer.amd.com/assets/42413_sb7xx_rpr_pub_1.00.pdf
38  * - AMD SB800-Series Southbridges Register Reference Guide (RRG)
39  *   http://support.amd.com/us/Embedded_TechDocs/45482.pdf
40  * Please see the following for Watchdog Resource Table specification:
41  * - Watchdog Timer Hardware Requirements for Windows Server 2003 (WDRT)
42  *   http://www.microsoft.com/whdc/system/sysinternals/watchdog.mspx
43  * AMD SB600/SB7xx/SB8xx watchdog hardware seems to conform to the above
44  * specifications, but the table hasn't been spotted in the wild yet.
45  *
46  * $FreeBSD: src/sys/dev/amdsbwd/amdsbwd.c,v 1.3 2011/06/07 06:18:02 avg Exp $
47  */
48 
49 #include <sys/param.h>
50 #include <sys/kernel.h>
51 #include <sys/module.h>
52 #include <sys/systm.h>
53 #include <sys/sysctl.h>
54 #include <sys/bus.h>
55 #include <sys/rman.h>
56 #include <sys/resource.h>
57 #include <sys/wdog.h>
58 
59 #include <bus/isa/isavar.h>
60 #include <bus/pci/pcivar.h>
61 
62 #include "amd_chipset.h"
63 
64 /*
65  * Registers in the Watchdog IO space.
66  * See SB7xx RRG 2.3.4, WDRT.
67  */
68 #define	AMDSB_WD_CTRL			0x00
69 #define		AMDSB_WD_RUN		0x01
70 #define		AMDSB_WD_FIRED		0x02
71 #define		AMDSB_WD_SHUTDOWN	0x04
72 #define		AMDSB_WD_DISABLE	0x08
73 #define		AMDSB_WD_RESERVED	0x70
74 #define		AMDSB_WD_RELOAD		0x80
75 #define	AMDSB_WD_COUNT			0x04
76 #define		AMDSB_WD_COUNT_MASK	0xffff
77 #define	AMDSB_WDIO_REG_WIDTH		4
78 
79 #define	amdsbwd_verbose_printf(dev, ...)	\
80 	do {						\
81 		if (bootverbose)			\
82 			device_printf(dev, __VA_ARGS__);\
83 	} while (0)
84 
85 struct amdsbwd_softc {
86 	device_t		dev;
87 	struct watchdog		wdog;
88 	struct resource		*res_ctrl;
89 	struct resource		*res_count;
90 	int			rid_ctrl;
91 	int			rid_count;
92 	int			ms_per_tick;
93 	int			max_ticks;
94 	int			active;
95 	unsigned int		timeout;
96 };
97 
98 static void	amdsbwd_identify(driver_t *driver, device_t parent);
99 static int	amdsbwd_probe(device_t dev);
100 static int	amdsbwd_attach(device_t dev);
101 static int	amdsbwd_detach(device_t dev);
102 static int	amdsbwd_suspend(device_t dev);
103 static int	amdsbwd_resume(device_t dev);
104 
105 static device_method_t amdsbwd_methods[] = {
106 	DEVMETHOD(device_identify,	amdsbwd_identify),
107 	DEVMETHOD(device_probe,		amdsbwd_probe),
108 	DEVMETHOD(device_attach,	amdsbwd_attach),
109 	DEVMETHOD(device_detach,	amdsbwd_detach),
110 	DEVMETHOD(device_suspend,	amdsbwd_suspend),
111 	DEVMETHOD(device_resume,	amdsbwd_resume),
112 #if 0
113 	DEVMETHOD(device_shutdown,	amdsbwd_detach),
114 #endif
115 	DEVMETHOD_END
116 };
117 
118 static devclass_t	amdsbwd_devclass;
119 static driver_t		amdsbwd_driver = {
120 	"amdsbwd",
121 	amdsbwd_methods,
122 	sizeof(struct amdsbwd_softc)
123 };
124 
125 DRIVER_MODULE(amdsbwd, isa, amdsbwd_driver, amdsbwd_devclass, NULL, NULL);
126 MODULE_VERSION(amdsbwd, 1);
127 
128 
129 static uint8_t
130 pmio_read(struct resource *res, uint8_t reg)
131 {
132 	bus_write_1(res, 0, reg);	/* Index */
133 	return (bus_read_1(res, 1));	/* Data */
134 }
135 
136 static void
137 pmio_write(struct resource *res, uint8_t reg, uint8_t val)
138 {
139 	bus_write_1(res, 0, reg);	/* Index */
140 	bus_write_1(res, 1, val);	/* Data */
141 }
142 
143 static uint32_t
144 wdctrl_read(struct amdsbwd_softc *sc)
145 {
146 	return (bus_read_4(sc->res_ctrl, 0));
147 }
148 
149 static void
150 wdctrl_write(struct amdsbwd_softc *sc, uint32_t val)
151 {
152 	bus_write_4(sc->res_ctrl, 0, val);
153 }
154 
155 static __unused uint32_t
156 wdcount_read(struct amdsbwd_softc *sc)
157 {
158 	return (bus_read_4(sc->res_count, 0));
159 }
160 
161 static void
162 wdcount_write(struct amdsbwd_softc *sc, uint32_t val)
163 {
164 	bus_write_4(sc->res_count, 0, val);
165 }
166 
167 static void
168 amdsbwd_tmr_enable(struct amdsbwd_softc *sc)
169 {
170 	uint32_t val;
171 
172 	val = wdctrl_read(sc);
173 	val |= AMDSB_WD_RUN;
174 	wdctrl_write(sc, val);
175 	sc->active = 1;
176 	amdsbwd_verbose_printf(sc->dev, "timer enabled\n");
177 }
178 
179 static void
180 amdsbwd_tmr_disable(struct amdsbwd_softc *sc)
181 {
182 	uint32_t val;
183 
184 	val = wdctrl_read(sc);
185 	val &= ~AMDSB_WD_RUN;
186 	wdctrl_write(sc, val);
187 	sc->active = 0;
188 	amdsbwd_verbose_printf(sc->dev, "timer disabled\n");
189 }
190 
191 static void
192 amdsbwd_tmr_reload(struct amdsbwd_softc *sc)
193 {
194 	uint32_t val;
195 
196 	val = wdctrl_read(sc);
197 	val |= AMDSB_WD_RELOAD;
198 	wdctrl_write(sc, val);
199 }
200 
201 static void
202 amdsbwd_tmr_set(struct amdsbwd_softc *sc, uint16_t timeout)
203 {
204 
205 	timeout &= AMDSB_WD_COUNT_MASK;
206 	wdcount_write(sc, timeout);
207 	sc->timeout = timeout;
208 	amdsbwd_verbose_printf(sc->dev, "timeout set to %u ticks\n", timeout);
209 }
210 
211 static int
212 amdsb_watchdog(void *arg, int period)
213 {
214 	unsigned int timeout;
215 	struct amdsbwd_softc *sc = arg;
216 
217 	timeout = (period * 1000) / sc->ms_per_tick;
218 	if (timeout > sc->max_ticks)
219 		timeout = sc->max_ticks;
220 	if (timeout != sc->timeout) {
221 		amdsbwd_tmr_set(sc, timeout);
222 		if (!sc->active)
223 			amdsbwd_tmr_enable(sc);
224 	}
225 	amdsbwd_tmr_reload(sc);
226 
227 	return period;
228 }
229 
230 static void
231 amdsbwd_identify(driver_t *driver, device_t parent)
232 {
233 	device_t		child;
234 	device_t		smb_dev;
235 
236 	if (resource_disabled("amdsbwd", 0))
237 		return;
238 	if (device_find_child(parent, "amdsbwd", -1) != NULL)
239 		return;
240 
241 	/*
242 	 * Try to identify SB600/SB7xx by PCI Device ID of SMBus device
243 	 * that should be present at bus 0, device 20, function 0.
244 	 */
245 	smb_dev = pci_find_bsf(0, 20, 0);
246 	if (smb_dev == NULL)
247 		return;
248 	if (pci_get_devid(smb_dev) != AMDSB_SMBUS_DEVID &&
249 	    pci_get_devid(smb_dev) != AMDFCH_SMBUS_DEVID &&
250 	    pci_get_devid(smb_dev) != AMDCZ_SMBUS_DEVID) {
251 		return;
252 	}
253 
254 	child = BUS_ADD_CHILD(parent, parent, ISA_ORDER_SPECULATIVE,
255 			      "amdsbwd", -1);
256 	if (child == NULL)
257 		device_printf(parent, "add amdsbwd child failed\n");
258 }
259 
260 
261 static void
262 amdsbwd_probe_sb7xx(device_t dev, struct resource *pmres, uint32_t *addr)
263 {
264 	uint8_t	val;
265 	int	i;
266 
267 	/* Report cause of previous reset for user's convenience. */
268 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS0);
269 	if (val != 0)
270 		amdsbwd_verbose_printf(dev, "ResetStatus0 = %#04x\n", val);
271 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS1);
272 	if (val != 0)
273 		amdsbwd_verbose_printf(dev, "ResetStatus1 = %#04x\n", val);
274 	if ((val & AMDSB_WD_RST_STS) != 0)
275 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
276 
277 	/* Find base address of memory mapped WDT registers. */
278 	for (*addr = 0, i = 0; i < 4; i++) {
279 		*addr <<= 8;
280 		*addr |= pmio_read(pmres, AMDSB_PM_WDT_BASE_MSB - i);
281 	}
282 	*addr &= ~0x07U;
283 
284 	/* Set watchdog timer tick to 1s. */
285 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
286 	val &= ~AMDSB_WDT_RES_MASK;
287 	val |= AMDSB_WDT_RES_1S;
288 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
289 
290 	/* Enable watchdog device (in stopped state). */
291 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
292 	val &= ~AMDSB_WDT_DISABLE;
293 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
294 
295 	/*
296 	 * XXX TODO: Ensure that watchdog decode is enabled
297 	 * (register 0x41, bit 3).
298 	 */
299 	device_set_desc(dev, "AMD SB600/SB7xx Watchdog Timer");
300 }
301 
302 static void
303 amdsbwd_probe_sb8xx(device_t dev, struct resource *pmres, uint32_t *addr)
304 {
305 	uint32_t	val;
306 	int		i;
307 
308 	/* Report cause of previous reset for user's convenience. */
309 
310 	val = pmio_read(pmres, AMDSB8_PM_RESET_CTRL);
311 	if ((val & AMDSB8_RST_STS_DIS) != 0) {
312 		val &= ~AMDSB8_RST_STS_DIS;
313 		pmio_write(pmres, AMDSB8_PM_RESET_CTRL, val);
314 	}
315 	val = 0;
316 	for (i = 3; i >= 0; i--) {
317 		val <<= 8;
318 		val |= pmio_read(pmres, AMDSB8_PM_RESET_STATUS + i);
319 	}
320 	if (val != 0)
321 		amdsbwd_verbose_printf(dev, "ResetStatus = 0x%08x\n", val);
322 	if ((val & AMDSB8_WD_RST_STS) != 0)
323 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
324 
325 	/* Find base address of memory mapped WDT registers. */
326 	for (*addr = 0, i = 0; i < 4; i++) {
327 		*addr <<= 8;
328 		*addr |= pmio_read(pmres, AMDSB8_PM_WDT_EN + 3 - i);
329 	}
330 	*addr &= ~0x07u;
331 
332 	/* Set watchdog timer tick to 1s. */
333 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
334 	val &= ~AMDSB8_WDT_RES_MASK;
335 	val |= AMDSB8_WDT_1HZ;
336 	pmio_write(pmres, AMDSB8_PM_WDT_CTRL, val);
337 #ifdef AMDSBWD_DEBUG
338 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
339 	amdsbwd_verbose_printf(dev, "AMDSB8_PM_WDT_CTRL value = %#04x\n", val);
340 #endif
341 
342 	/*
343 	 * Enable watchdog device (in stopped state)
344 	 * and decoding of its address.
345 	 */
346 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
347 	val &= ~AMDSB8_WDT_DISABLE;
348 	val |= AMDSB8_WDT_DEC_EN;
349 	pmio_write(pmres, AMDSB8_PM_WDT_EN, val);
350 #ifdef AMDSBWD_DEBUG
351 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
352 	device_printf(dev, "AMDSB8_PM_WDT_EN value = %#02x\n", val);
353 #endif
354 	device_set_desc(dev, "AMD SB8xx/SB9xx/Axx Watchdog Timer");
355 }
356 
357 static void
358 amdsbwd_probe_fch41(device_t dev, struct resource *pmres, uint32_t *addr)
359 {
360 	uint8_t val;
361 
362 	val = pmio_read(pmres, AMDFCH41_PM_ISA_CTRL);
363 	if ((val & AMDFCH41_MMIO_EN) != 0) {
364 		/* Fixed offset for the watchdog within ACPI MMIO range. */
365 		amdsbwd_verbose_printf(dev, "ACPI MMIO range is enabled\n");
366 		*addr = AMDFCH41_MMIO_ADDR + AMDFCH41_MMIO_WDT_OFF;
367 	} else {
368 		/*
369 		 * Enable decoding of watchdog MMIO address.
370 		 */
371 		val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN0);
372 		val |= AMDFCH41_WDT_EN;
373 		pmio_write(pmres, AMDFCH41_PM_DECODE_EN0, val);
374 #ifdef AMDSBWD_DEBUG
375 		val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN0);
376 		device_printf(dev, "AMDFCH41_PM_DECODE_EN0 value = %#04x\n",
377 		    val);
378 #endif
379 
380 		/* Special fixed MMIO range for the watchdog. */
381 		*addr = AMDFCH41_WDT_FIXED_ADDR;
382 	}
383 
384 	/*
385 	 * Set watchdog timer tick to 1s and
386 	 * enable the watchdog device (in stopped state).
387 	 */
388 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN3);
389 	val &= ~AMDFCH41_WDT_RES_MASK;
390 	val |= AMDFCH41_WDT_RES_1S;
391 	val &= ~AMDFCH41_WDT_EN_MASK;
392 	val |= AMDFCH41_WDT_ENABLE;
393 	pmio_write(pmres, AMDFCH41_PM_DECODE_EN3, val);
394 #ifdef AMDSBWD_DEBUG
395 	val = pmio_read(pmres, AMDFCH41_PM_DECODE_EN3);
396 	amdsbwd_verbose_printf(dev, "AMDFCH41_PM_DECODE_EN3 value = %#04x\n",
397 	    val);
398 #endif
399 	device_set_desc(dev, "AMD FCH Rev 41h+ Watchdog Timer");
400 }
401 
402 static int
403 amdsbwd_probe(device_t dev)
404 {
405 	struct resource		*res;
406 	device_t		smb_dev;
407 	uint32_t		addr;
408 	int			rid;
409 	int			rc;
410 	uint32_t		devid;
411 	uint8_t			revid;
412 
413 	/* Do not claim some ISA PnP device by accident. */
414 	if (isa_get_logicalid(dev) != 0)
415 		return (ENXIO);
416 
417 	rc = bus_set_resource(dev, SYS_RES_IOPORT, 0, AMDSB_PMIO_INDEX,
418 			      AMDSB_PMIO_WIDTH, -1);
419 	if (rc != 0) {
420 		device_printf(dev, "bus_set_resource for IO failed\n");
421 		return (ENXIO);
422 	}
423 	rid = 0;
424 	res = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0ul, ~0ul,
425 	    AMDSB_PMIO_WIDTH, RF_ACTIVE | RF_SHAREABLE);
426 	if (res == NULL) {
427 		device_printf(dev, "bus_alloc_resource for IO failed\n");
428 		return (ENXIO);
429 	}
430 
431 	smb_dev = pci_find_bsf(0, 20, 0);
432 	KASSERT(smb_dev != NULL, ("can't find SMBus PCI device\n"));
433 	devid = pci_get_devid(smb_dev);
434 	revid = pci_get_revid(smb_dev);
435 	if (devid == AMDSB_SMBUS_DEVID && revid < AMDSB8_SMBUS_REVID) {
436 		amdsbwd_probe_sb7xx(dev, res, &addr);
437 	} else if (devid == AMDSB_SMBUS_DEVID ||
438 	     (devid == AMDFCH_SMBUS_DEVID && revid < AMDFCH41_SMBUS_REVID) ||
439 	     (devid == AMDCZ_SMBUS_DEVID  && revid < AMDCZ49_SMBUS_REVID)) {
440 		amdsbwd_probe_sb8xx(dev, res, &addr);
441 	} else {
442 		amdsbwd_probe_fch41(dev, res, &addr);
443 	}
444 
445 	bus_release_resource(dev, SYS_RES_IOPORT, rid, res);
446 	bus_delete_resource(dev, SYS_RES_IOPORT, rid);
447 
448 	amdsbwd_verbose_printf(dev, "memory base address = %#010x\n", addr);
449 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 0, addr + AMDSB_WD_CTRL,
450 			      AMDSB_WDIO_REG_WIDTH, -1);
451 	if (rc != 0) {
452 		device_printf(dev, "bus_set_resource for control failed\n");
453 		return (ENXIO);
454 	}
455 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 1, addr + AMDSB_WD_COUNT,
456 			      AMDSB_WDIO_REG_WIDTH, -1);
457 	if (rc != 0) {
458 		device_printf(dev, "bus_set_resource for count failed\n");
459 		return (ENXIO);
460 	}
461 
462 	return (0);
463 }
464 
465 static int
466 amdsbwd_attach_sb(device_t dev, struct amdsbwd_softc *sc)
467 {
468 	sc->max_ticks = UINT16_MAX;
469 	sc->rid_ctrl = 0;
470 	sc->rid_count = 1;
471 
472 	sc->ms_per_tick = 1000;
473 
474 	sc->res_ctrl = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
475 	    &sc->rid_ctrl, RF_ACTIVE);
476 	if (sc->res_ctrl == NULL) {
477 		device_printf(dev, "bus_alloc_resource for ctrl failed\n");
478 		return (ENXIO);
479 	}
480 	sc->res_count = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
481 	    &sc->rid_count, RF_ACTIVE);
482 	if (sc->res_count == NULL) {
483 		device_printf(dev, "bus_alloc_resource for count failed\n");
484 		return (ENXIO);
485 	}
486 	return (0);
487 }
488 
489 static int
490 amdsbwd_attach(device_t dev)
491 {
492 	struct amdsbwd_softc	*sc;
493 	int			rc;
494 
495 	sc = device_get_softc(dev);
496 	sc->dev = dev;
497 
498 	rc = amdsbwd_attach_sb(dev, sc);
499 	if (rc != 0)
500 		goto fail;
501 
502 #ifdef AMDSBWD_DEBUG
503 	device_printf(dev, "wd ctrl = %#04x\n", wdctrl_read(sc));
504 	device_printf(dev, "wd count = %#04x\n", wdcount_read(sc));
505 #endif
506 
507 	/* Setup initial state of Watchdog Control. */
508 	wdctrl_write(sc, AMDSB_WD_FIRED);
509 
510 	if (wdctrl_read(sc) & AMDSB_WD_DISABLE) {
511 		device_printf(dev, "watchdog hardware is disabled\n");
512 		goto fail;
513 	}
514 
515 	sc->wdog.name = "AMD southbridge";
516 	sc->wdog.wdog_fn = amdsb_watchdog;
517 	sc->wdog.arg = sc;
518 	sc->wdog.period_max = (UINT16_MAX*1000) / 10;
519 	wdog_register(&sc->wdog);
520 
521 	return (0);
522 
523 fail:
524 	amdsbwd_detach(dev);
525 	return (ENXIO);
526 }
527 
528 static int
529 amdsbwd_detach(device_t dev)
530 {
531 	struct amdsbwd_softc *sc;
532 
533 	sc = device_get_softc(dev);
534 	if (sc->wdog.name)
535 		wdog_unregister(&sc->wdog);
536 
537 	if (sc->active)
538 		amdsbwd_tmr_disable(sc);
539 
540 	if (sc->res_ctrl != NULL)
541 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_ctrl,
542 		    sc->res_ctrl);
543 
544 	if (sc->res_count != NULL)
545 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_count,
546 		    sc->res_count);
547 
548 	return (0);
549 }
550 
551 static int
552 amdsbwd_suspend(device_t dev)
553 {
554 	struct amdsbwd_softc *sc;
555 	uint32_t val;
556 
557 	sc = device_get_softc(dev);
558 	val = wdctrl_read(sc);
559 	val &= ~AMDSB_WD_RUN;
560 	wdctrl_write(sc, val);
561 	return (0);
562 }
563 
564 static int
565 amdsbwd_resume(device_t dev)
566 {
567 	struct amdsbwd_softc *sc;
568 
569 	sc = device_get_softc(dev);
570 	wdctrl_write(sc, AMDSB_WD_FIRED);
571 	if (sc->active) {
572 		amdsbwd_tmr_set(sc, sc->timeout);
573 		amdsbwd_tmr_enable(sc);
574 		amdsbwd_tmr_reload(sc);
575 	}
576 	return (0);
577 }
578