xref: /freebsd/sys/dev/wbwd/wbwd.c (revision 9a41df2a0e6408e9b329bbd8b9e37c2b44461a1b)
1 /*-
2  * Copyright (c) 2011 Sandvine Incorporated ULC.
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  * Support for Winbond watchdog.
28  *
29  * With minor abstractions it might be possible to add support for other
30  * different Winbond Super I/O chips as well.  Winbond seems to have four
31  * different types of chips, four different ways to get into extended config
32  * mode.
33  *
34  * Note: there is no serialization between the debugging sysctl handlers and
35  * the watchdog functions and possibly others poking the registers at the same
36  * time.  For that at least possibly interfering sysctls are hidden by default.
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/kernel.h>
44 #include <sys/systm.h>
45 #include <sys/bus.h>
46 #include <sys/eventhandler.h>
47 #include <sys/lock.h>
48 #include <sys/module.h>
49 #include <sys/rman.h>
50 #include <sys/sbuf.h>
51 #include <sys/sysctl.h>
52 #include <sys/watchdog.h>
53 
54 #include <isa/isavar.h>
55 
56 #include <machine/bus.h>
57 #include <machine/resource.h>
58 
59 /*
60  * Global registers.
61  */
62 #define	WB_DEVICE_ID_REG	0x20	/* Device ID */
63 #define	WB_DEVICE_REV_REG	0x21	/* Device revision */
64 #define	WB_CR26			0x26	/* Bit6: HEFRAS (base port selector) */
65 
66 /* LDN selection. */
67 #define	WB_LDN_REG		0x07
68 #define	WB_LDN_REG_LDN8		0x08	/* GPIO 2, Watchdog */
69 
70 /*
71  * LDN8 (GPIO 2, Watchdog) specific registers and options.
72  */
73 /* CR30: LDN8 activation control. */
74 #define	WB_LDN8_CR30		0x30
75 #define	WB_LDN8_CR30_ACTIVE	0x01	/* 1: LD active */
76 
77 /* CRF5: Watchdog scale, P20. Mapped to reg_1. */
78 #define	WB_LDN8_CRF5		0xF5
79 #define	WB_LDN8_CRF5_SCALE	0x08	/* 0: 1s, 1: 60s */
80 #define	WB_LDN8_CRF5_KEYB_P20	0x04	/* 1: keyb P20 forces timeout */
81 #define	WB_LDN8_CRF5_KBRST	0x02	/* 1: timeout causes pin60 kbd reset */
82 
83 /* CRF6: Watchdog Timeout (0 == off). Mapped to reg_timeout. */
84 #define	WB_LDN8_CRF6		0xF6
85 
86 /* CRF7: Watchdog mouse, keyb, force, .. Mapped to reg_2. */
87 #define	WB_LDN8_CRF7		0xF7
88 #define	WB_LDN8_CRF7_MOUSE	0x80	/* 1: mouse irq resets wd timer */
89 #define	WB_LDN8_CRF7_KEYB	0x40	/* 1: keyb irq resets wd timer */
90 #define	WB_LDN8_CRF7_FORCE	0x20	/* 1: force timeout (self-clear) */
91 #define	WB_LDN8_CRF7_TS		0x10	/* 0: counting, 1: fired */
92 #define	WB_LDN8_CRF7_IRQS	0x0f	/* irq source for watchdog, 2 == SMI */
93 #define	WB_LDN8_CRF7_CLEAR_MASK	\
94     (WB_LDN8_CRF7_MOUSE|WB_LDN8_CRF7_KEYB|WB_LDN8_CRF7_TS|WB_LDN8_CRF7_IRQS)
95 
96 #define	write_efir_1(sc, value)						\
97 	bus_space_write_1((sc)->bst, (sc)->bsh, 0, (value))
98 #define	read_efir_1(sc)							\
99 	bus_space_read_1((sc)->bst, (sc)->bsh, 0)
100 #define	write_efdr_1(sc, value)						\
101 	bus_space_write_1((sc)->bst, (sc)->bsh, 1, (value))
102 #define	read_efdr_1(sc)							\
103 	bus_space_read_1((sc)->bst, (sc)->bsh, 1)
104 
105 struct wb_softc {
106 	device_t		dev;
107 	struct resource		*portres;
108 	bus_space_tag_t		bst;
109 	bus_space_handle_t	bsh;
110 	int			rid;
111 	eventhandler_tag	ev_tag;
112 	int			(*ext_cfg_enter_f)(struct wb_softc *);
113 	void			(*ext_cfg_exit_f)(struct wb_softc *);
114 	int			debug_verbose;
115 
116 	/*
117 	 * Special feature to let the watchdog fire at a different
118 	 * timeout as set by watchdog(4) but still use that API to
119 	 * re-load it periodically.
120 	 */
121 	unsigned int		timeout_override;
122 
123 	/*
124 	 * Space to save current state temporary and for sysctls.
125 	 * We want to know the timeout value and usually need two
126 	 * additional registers for options. Do not name them by
127 	 * register as these might be different by chip.
128 	 */
129 	uint8_t			reg_timeout;
130 	uint8_t			reg_1;
131 	uint8_t			reg_2;
132 };
133 
134 static int	ext_cfg_enter_0x87_0x87(struct wb_softc *);
135 static void	ext_cfg_exit_0xaa(struct wb_softc *);
136 
137 struct winbond_superio_cfg {
138 	uint8_t			efer;	/* and efir */
139 	int			(*ext_cfg_enter_f)(struct wb_softc *);
140 	void			(*ext_cfg_exit_f)(struct wb_softc *);
141 } probe_addrs[] = {
142 	{
143 		.efer			= 0x2e,
144 		.ext_cfg_enter_f	= ext_cfg_enter_0x87_0x87,
145 		.ext_cfg_exit_f		= ext_cfg_exit_0xaa,
146 	},
147 	{
148 		.efer			= 0x4e,
149 		.ext_cfg_enter_f	= ext_cfg_enter_0x87_0x87,
150 		.ext_cfg_exit_f		= ext_cfg_exit_0xaa,
151 	},
152 };
153 
154 struct winbond_vendor_device_id {
155 	uint16_t		vendor_id;
156 	uint8_t			device_id;
157 	uint8_t			device_rev;
158 	const char *		descr;
159 } wb_devs[] = {
160 	{
161 		.vendor_id	= 0x5ca3,
162 		.device_id	= 0x52,
163 		.device_rev	= 0x17,
164 		.descr		= "Winbond 83627HF/F/HG/G Rev. G",
165 	},
166 	{
167 		.vendor_id	= 0x5ca3,
168 		.device_id	= 0x52,
169 		.device_rev	= 0x3a,
170 		.descr		= "Winbond 83627HF/F/HG/G Rev. J",
171 	},
172 	{
173 		.vendor_id	= 0x5ca3,
174 		.device_id	= 0x52,
175 		.device_rev	= 0x41,
176 		.descr		= "Winbond 83627HF/F/HG/G Rev. UD-A",
177 	},
178 	{
179 		.vendor_id	= 0x5ca3,
180 		.device_id	= 0xa0,
181 		.device_rev	= 0x25,
182 		.descr		= "Winbond 83627DHG IC ver. 5",
183 	},
184 	{
185 		.vendor_id	= 0x5ca3,
186 		.device_id	= 0xb0,
187 		.device_rev	= 0x73,
188 		.descr		= "Winbond 83627DHG-P",
189 	},
190 };
191 
192 /*
193  * Return the watchdog related registers as we last read them.  This will
194  * usually not give the current timeout or state on whether the watchdog
195  * fired.
196  */
197 static int
198 sysctl_wb_debug(SYSCTL_HANDLER_ARGS)
199 {
200 	struct wb_softc *sc;
201 	struct sbuf sb;
202 	int error;
203 
204 	sc = arg1;
205 
206 	sbuf_new_for_sysctl(&sb, NULL, 64, req);
207 
208 	sbuf_printf(&sb, "LDN8 (GPIO2, Watchdog): ");
209 	sbuf_printf(&sb, "CRF5 0x%02x ", sc->reg_1);
210 	sbuf_printf(&sb, "CRF6 0x%02x ", sc->reg_timeout);
211 	sbuf_printf(&sb, "CRF7 0x%02x ", sc->reg_2);
212 
213 	sbuf_trim(&sb);
214 	error = sbuf_finish(&sb);
215 	sbuf_delete(&sb);
216 	return (error);
217 }
218 
219 /*
220  * Read the current values before returning them.  Given this might poke
221  * the registers the same time as the watchdog, this sysctl handler should
222  * be marked CTLFLAG_SKIP to not show up by default.
223  */
224 static int
225 sysctl_wb_debug_current(SYSCTL_HANDLER_ARGS)
226 {
227 	struct wb_softc *sc;
228 
229 	sc = arg1;
230 
231 	/*
232 	 * Enter extended function mode in case someone else has been
233 	 * poking on the registers.  We will not leave it though.
234 	 */
235 	if ((*sc->ext_cfg_enter_f)(sc) != 0)
236 		return (ENXIO);
237 
238 	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
239 	write_efir_1(sc, WB_LDN_REG);
240 	write_efdr_1(sc, WB_LDN_REG_LDN8);
241 
242 	write_efir_1(sc, WB_LDN8_CRF5);
243 	sc->reg_1 = read_efdr_1(sc);
244 	write_efir_1(sc, WB_LDN8_CRF6);
245 	sc->reg_timeout = read_efdr_1(sc);
246 	write_efir_1(sc, WB_LDN8_CRF7);
247 	sc->reg_2 = read_efdr_1(sc);
248 
249 	return (sysctl_wb_debug(oidp, arg1, arg2, req));
250 }
251 
252 /*
253  * Sysctl handlers to force a watchdog timeout or to test the NMI functionality
254  * works as expetced.
255  * For testing we could set a test_nmi flag in the softc that, in case of NMI, a
256  * callback function from trap.c could check whether we fired and not report the
257  * timeout but clear the flag for the sysctl again.  This is interesting given a
258  * lot of boards have jumpers to change the action on watchdog timeout or
259  * disable the watchdog completely.
260  * XXX-BZ notyet: currently no general infrastructure exists to do this.
261  */
262 static int
263 sysctl_wb_force_test_nmi(SYSCTL_HANDLER_ARGS)
264 {
265 	struct wb_softc *sc;
266 	int error, test, val;
267 
268 	sc = arg1;
269 	test = arg2;
270 
271 #ifdef notyet
272 	val = sc->test_nmi;
273 #else
274 	val = 0;
275 #endif
276 	error = sysctl_handle_int(oidp, &val, 0, req);
277         if (error || !req->newptr)
278                 return (error);
279 
280 #ifdef notyet
281 	/* Manually clear the test for a value of 0 and do nothing else. */
282 	if (test && val == 0) {
283 		sc->test_nmi = 0;
284 		return (0);
285 	}
286 #endif
287 
288 	/*
289 	 * Enter extended function mode in case someone else has been
290 	 * poking on the registers.  We will not leave it though.
291 	 */
292 	if ((*sc->ext_cfg_enter_f)(sc) != 0)
293 		return (ENXIO);
294 
295 #ifdef notyet
296 	/*
297 	 * If we are testing the NMI functionality, set the flag before
298 	 * forcing the timeout.
299 	 */
300 	if (test)
301 		sc->test_nmi = 1;
302 #endif
303 
304 	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
305 	write_efir_1(sc, WB_LDN_REG);
306 	write_efdr_1(sc, WB_LDN_REG_LDN8);
307 
308 	/* Force watchdog to fire. */
309 	write_efir_1(sc, WB_LDN8_CRF7);
310 	sc->reg_2 = read_efdr_1(sc);
311 	sc->reg_2 |= WB_LDN8_CRF7_FORCE;
312 
313 	write_efir_1(sc, WB_LDN8_CRF7);
314 	write_efdr_1(sc, sc->reg_2);
315 
316 	return (0);
317 }
318 
319 /*
320  * Print current watchdog state.
321  *
322  * Note: it is the responsibility of the caller to update the registers
323  * upfront.
324  */
325 static void
326 wb_print_state(struct wb_softc *sc, const char *msg)
327 {
328 
329 	device_printf(sc->dev, "%s%sWatchdog %sabled. %s"
330 	    "Scaling by %ds, timer at %d (%s=%ds%s). "
331 	    "CRF5 0x%02x CRF7 0x%02x\n",
332 	    (msg != NULL) ? msg : "", (msg != NULL) ? ": " : "",
333 	    (sc->reg_timeout > 0x00) ? "en" : "dis",
334 	    (sc->reg_2 & WB_LDN8_CRF7_TS) ? "Watchdog fired. " : "",
335 	    (sc->reg_1 & WB_LDN8_CRF5_SCALE) ? 60 : 1,
336 	    sc->reg_timeout,
337 	    (sc->reg_timeout > 0x00) ? "<" : "",
338 	    sc->reg_timeout * ((sc->reg_1 & WB_LDN8_CRF5_SCALE) ? 60 : 1),
339 	    (sc->reg_timeout > 0x00) ? " left" : "",
340 	    sc->reg_1, sc->reg_2);
341 }
342 
343 /*
344  * Functions to enter and exit extended function mode.  Possibly shared
345  * between different chips.
346  */
347 static int
348 ext_cfg_enter_0x87_0x87(struct wb_softc *sc)
349 {
350 
351 	/*
352 	 * Enable extended function mode.
353 	 * Winbond does not allow us to validate so always return success.
354 	 */
355 	write_efir_1(sc, 0x87);
356 	write_efir_1(sc, 0x87);
357 
358 	return (0);
359 }
360 
361 static void
362 ext_cfg_exit_0xaa(struct wb_softc *sc)
363 {
364 
365 	write_efir_1(sc, 0xaa);
366 }
367 
368 /*
369  * (Re)load the watchdog counter depending on timeout.  A timeout of 0 will
370  * disable the watchdog.
371  */
372 static int
373 wb_set_watchdog(struct wb_softc *sc, unsigned int timeout)
374 {
375 
376 	if (sc->debug_verbose)
377 		wb_print_state(sc, "Before watchdog counter (re)load");
378 
379 	/*
380 	 * Enter extended function mode in case someone else has been
381 	 * poking on the registers.  We will not leave it though.
382 	 */
383 	if ((*sc->ext_cfg_enter_f)(sc) != 0)
384 		return (ENXIO);
385 
386 	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog) */
387 	write_efir_1(sc, WB_LDN_REG);
388 	write_efdr_1(sc, WB_LDN_REG_LDN8);
389 
390 	/* Disable and validate or arm/reset watchdog. */
391 	if (timeout == 0) {
392 		/* Disable watchdog. */
393 		write_efir_1(sc, WB_LDN8_CRF6);
394 		write_efdr_1(sc, 0x00);
395 
396 		/* Re-check. */
397 		write_efir_1(sc, WB_LDN8_CRF6);
398 		sc->reg_timeout = read_efdr_1(sc);
399 
400 		if (sc->reg_timeout != 0x00) {
401 			device_printf(sc->dev, "Failed to disable watchdog: "
402 			    "0x%02x.\n", sc->reg_timeout);
403 			return (EIO);
404 		}
405 
406 	} else {
407 		/*
408 		 * In case an override is set, let it override.  It may lead
409 		 * to strange results as we do not check the input of the sysctl.
410 		 */
411 		if (sc->timeout_override > 0)
412 			timeout = sc->timeout_override;
413 
414 		/* Make sure we support the requested timeout. */
415 		if (timeout > 255 * 60)
416 			return (EINVAL);
417 
418 		/* Read current scaling factor. */
419 		write_efir_1(sc, WB_LDN8_CRF5);
420 		sc->reg_1 = read_efdr_1(sc);
421 
422 		if (timeout > 255) {
423 			/* Set scaling factor to 60s. */
424 			sc->reg_1 |= WB_LDN8_CRF5_SCALE;
425 			sc->reg_timeout = (timeout / 60);
426 			if (timeout % 60)
427 				sc->reg_timeout++;
428 		} else {
429 			/* Set scaling factor to 1s. */
430 			sc->reg_1 &= ~WB_LDN8_CRF5_SCALE;
431 			sc->reg_timeout = timeout;
432 		}
433 
434 		/* In case we fired before we need to clear to fire again. */
435 		write_efir_1(sc, WB_LDN8_CRF7);
436 		sc->reg_2 = read_efdr_1(sc);
437 		if (sc->reg_2 & WB_LDN8_CRF7_TS) {
438 			sc->reg_2 &= ~WB_LDN8_CRF7_TS;
439 			write_efir_1(sc, WB_LDN8_CRF7);
440 			write_efdr_1(sc, sc->reg_2);
441 		}
442 
443 		/* Write back scaling factor. */
444 		write_efir_1(sc, WB_LDN8_CRF5);
445 		write_efdr_1(sc, sc->reg_1);
446 
447 		/* Set timer and arm/reset the watchdog. */
448 		write_efir_1(sc, WB_LDN8_CRF6);
449 		write_efdr_1(sc, sc->reg_timeout);
450 	}
451 
452 	if (sc->debug_verbose)
453 		wb_print_state(sc, "After watchdog counter (re)load");
454 
455 	return (0);
456 }
457 
458 /*
459  * watchdog(9) EVENTHANDLER function implementation to (re)load the counter
460  * with the given timeout or disable the watchdog.
461  */
462 static void
463 wb_watchdog_fn(void *private, u_int cmd, int *error)
464 {
465 	struct wb_softc *sc;
466 	unsigned int timeout;
467 	int e;
468 
469 	sc = private;
470 	KASSERT(sc != NULL, ("%s: watchdog handler function called without "
471 	    "softc.", __func__));
472 
473 	cmd &= WD_INTERVAL;
474 	if (cmd > 0 && cmd <= 63) {
475 		/* Reset (and arm) watchdog. */
476 		timeout = ((uint64_t)1 << cmd) / 1000000000;
477 		if (timeout == 0)
478 			timeout = 1;
479 		e = wb_set_watchdog(sc, timeout);
480 		if (e == 0) {
481 			if (error != NULL)
482 				*error = 0;
483 		} else {
484 			/* On error, try to make sure the WD is disabled. */
485 			wb_set_watchdog(sc, 0);
486 		}
487 
488 	} else {
489 		/* Disable watchdog. */
490 		e = wb_set_watchdog(sc, 0);
491 		if (e != 0 && cmd == 0 && error != NULL) {
492 			/* Failed to disable watchdog. */
493 			*error = EOPNOTSUPP;
494 		}
495 	}
496 }
497 
498 /*
499  * Probe/attach the Winbond Super I/O chip.
500  *
501  * Initial abstraction to possibly support more chips:
502  * - Iterate over the well known base ports, try to enable extended function
503  *   mode and read and match the device ID and device revision.  Unfortunately
504  *   the Vendor ID is in the hardware monitoring section accessible by different
505  *   base ports only.
506  * - Also HEFRAS, which would tell use the base port, is only accessible after
507  *   entering extended function mode, for which the base port is needed.
508  *   At least check HEFRAS to match the current base port we are probing.
509  * - On match set the description, remember functions to enter/exit extended
510  *   function mode as well as the base port.
511  */
512 static int
513 wb_probe_enable(device_t dev, int probe)
514 {
515 	struct wb_softc *sc;
516 	int error, found, i, j;
517 	uint8_t dev_id, dev_rev, cr26;
518 
519 	sc = device_get_softc(dev);
520 	bzero(sc, sizeof(*sc));
521 	sc->dev = dev;
522 
523 	error = ENXIO;
524 	for (i = 0; i < sizeof(probe_addrs) / sizeof(*probe_addrs); i++) {
525 
526 		/* Allocate bus resources for IO index/data register access. */
527 		sc->portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->rid,
528 		    probe_addrs[i].efer, probe_addrs[i].efer + 1, 2, RF_ACTIVE);
529 		if (sc->portres == NULL)
530 			continue;
531 		sc->bst = rman_get_bustag(sc->portres);
532 		sc->bsh = rman_get_bushandle(sc->portres);
533 
534 		found = 0;
535 		error = (*probe_addrs[i].ext_cfg_enter_f)(sc);
536 		if (error != 0)
537 			goto cleanup;
538 
539 		/* Identify the SuperIO chip. */
540 		write_efir_1(sc, WB_DEVICE_ID_REG);
541 		dev_id = read_efdr_1(sc);
542 		write_efir_1(sc, WB_DEVICE_REV_REG);
543 		dev_rev = read_efdr_1(sc);
544 		write_efir_1(sc, WB_CR26);
545 		cr26 = read_efdr_1(sc);
546 
547 		/* HEFRAS of 0 means EFER at 0x2e, 1 means EFER at 0x4e. */
548 		if (((cr26 & 0x40) == 0x00 && probe_addrs[i].efer != 0x2e) ||
549 		    ((cr26 & 0x40) == 0x40 && probe_addrs[i].efer != 0x4e)) {
550 			device_printf(dev, "HEFRAS and EFER do not align: EFER "
551 			    "0x%02x DevID 0x%02x DevRev 0x%02x CR26 0x%02x\n",
552 			     probe_addrs[i].efer, dev_id, dev_rev, cr26);
553 			goto cleanup;
554 		}
555 
556 		for (j = 0; j < sizeof(wb_devs) / sizeof(*wb_devs); j++) {
557 			if (wb_devs[j].device_id == dev_id &&
558 			    wb_devs[j].device_rev == dev_rev) {
559 				if (probe)
560 					device_set_desc(dev, wb_devs[j].descr);
561 				found++;
562 				break;
563 			}
564 		}
565 		if (probe && found && bootverbose)
566 			device_printf(dev, "%s EFER 0x%02x ID 0x%02x Rev 0x%02x"
567 			     " CR26 0x%02x (probing)\n", device_get_desc(dev),
568 			     probe_addrs[i].efer, dev_id, dev_rev, cr26);
569 cleanup:
570 		if (probe || !found) {
571 			(*probe_addrs[i].ext_cfg_exit_f)(sc);
572 
573 			(void) bus_release_resource(dev, SYS_RES_IOPORT, sc->rid,
574 			    sc->portres);
575 		}
576 
577 		/*
578 		 * Stop probing if have successfully identified the SuperIO.
579 		 * Remember the extended function mode enter/exit functions
580 		 * for operations.
581 		 */
582 		if (found) {
583 			sc->ext_cfg_enter_f = probe_addrs[i].ext_cfg_enter_f;
584 			sc->ext_cfg_exit_f = probe_addrs[i].ext_cfg_exit_f;
585 			error = BUS_PROBE_DEFAULT;
586 			break;
587 		} else
588 			error = ENXIO;
589 	}
590 
591 	return (error);
592 }
593 
594 static int
595 wb_probe(device_t dev)
596 {
597 
598 	/* Make sure we do not claim some ISA PNP device. */
599 	if (isa_get_logicalid(dev) != 0)
600 		return (ENXIO);
601 
602 	return (wb_probe_enable(dev, 1));
603 }
604 
605 static int
606 wb_attach(device_t dev)
607 {
608 	struct wb_softc *sc;
609 	struct sysctl_ctx_list *sctx;
610 	struct sysctl_oid *soid;
611 	unsigned long timeout;
612 	int error;
613 
614 	error = wb_probe_enable(dev, 0);
615 	if (error > 0)
616 		return (ENXIO);
617 
618 	sc = device_get_softc(dev);
619 	KASSERT(sc->ext_cfg_enter_f != NULL && sc->ext_cfg_exit_f != NULL,
620 	    ("%s: successfull probe result but not setup correctly", __func__));
621 
622 	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
623 	write_efir_1(sc, WB_LDN_REG);
624 	write_efdr_1(sc, WB_LDN_REG_LDN8);
625 
626 	/* Make sure LDN8 is enabled (Do we need to? Also affects GPIO). */
627 	write_efir_1(sc, WB_LDN8_CR30);
628 	write_efdr_1(sc, WB_LDN8_CR30_ACTIVE);
629 
630 	/* Read the current watchdog configuration. */
631 	write_efir_1(sc, WB_LDN8_CRF5);
632 	sc->reg_1 = read_efdr_1(sc);
633 	write_efir_1(sc, WB_LDN8_CRF6);
634 	sc->reg_timeout = read_efdr_1(sc);
635 	write_efir_1(sc, WB_LDN8_CRF7);
636 	sc->reg_2 = read_efdr_1(sc);
637 
638 	/* Print current state if bootverbose or watchdog already enabled. */
639 	if (bootverbose || (sc->reg_timeout > 0x00))
640 		wb_print_state(sc, "Before watchdog attach");
641 
642 	/*
643 	 * Clear a previous watchdog timeout event (if (still) set).
644 	 * Disable all all interrupt reset sources (defaults).
645 	 */
646 	sc->reg_1 &= ~(WB_LDN8_CRF5_KEYB_P20);
647 	sc->reg_1 |= WB_LDN8_CRF5_KBRST;
648 	write_efir_1(sc, WB_LDN8_CRF5);
649 	write_efdr_1(sc, sc->reg_1);
650 
651 	sc->reg_2 &= ~WB_LDN8_CRF7_CLEAR_MASK;
652 	write_efir_1(sc, WB_LDN8_CRF7);
653 	write_efdr_1(sc, sc->reg_2);
654 
655 	/* Read global timeout override tunable, Add per device sysctls. */
656 	if (TUNABLE_ULONG_FETCH("hw.wbwd.timeout_override", &timeout)) {
657 		if (timeout > 0)
658 			sc->timeout_override = timeout;
659 	}
660 	sctx = device_get_sysctl_ctx(dev);
661 	soid = device_get_sysctl_tree(dev);
662         SYSCTL_ADD_UINT(sctx, SYSCTL_CHILDREN(soid), OID_AUTO,
663 	    "timeout_override", CTLFLAG_RW, &sc->timeout_override, 0,
664             "Timeout in seconds overriding default watchdog timeout");
665         SYSCTL_ADD_INT(sctx, SYSCTL_CHILDREN(soid), OID_AUTO,
666 	    "debug_verbose", CTLFLAG_RW, &sc->debug_verbose, 0,
667             "Enables extra debugging information");
668         SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "debug",
669 	    CTLTYPE_STRING|CTLFLAG_RD, sc, 0, sysctl_wb_debug, "A",
670             "Selected register information from last change by driver");
671         SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "debug_current",
672 	    CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_SKIP, sc, 0,
673 	     sysctl_wb_debug_current, "A",
674 	     "Selected register information (may interfere)");
675 	SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "force_timeout",
676 	    CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_SKIP, sc, 0,
677 	    sysctl_wb_force_test_nmi, "I", "Enable to force watchdog to fire.");
678 
679 	/* Register watchdog. */
680 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, wb_watchdog_fn, sc,
681 	    0);
682 
683 	if (bootverbose)
684 		wb_print_state(sc, "After watchdog attach");
685 
686 	return (0);
687 }
688 
689 static int
690 wb_detach(device_t dev)
691 {
692 	struct wb_softc *sc;
693 
694 	sc = device_get_softc(dev);
695 
696 	/* Unregister and stop the watchdog if running. */
697 	if (sc->ev_tag)
698 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
699 	wb_set_watchdog(sc, 0);
700 
701 	/* Disable extended function mode. */
702 	(*sc->ext_cfg_exit_f)(sc);
703 
704 	/* Cleanup resources. */
705 	(void) bus_release_resource(dev, SYS_RES_IOPORT, sc->rid, sc->portres);
706 
707 	/* Bus subroutines take care of sysctls already. */
708 
709 	return (0);
710 }
711 
712 static device_method_t wb_methods[] = {
713 	/* Device interface */
714 	DEVMETHOD(device_probe,		wb_probe),
715 	DEVMETHOD(device_attach,	wb_attach),
716 	DEVMETHOD(device_detach,	wb_detach),
717 
718 	{ 0, 0 }
719 };
720 
721 static driver_t wb_isa_driver = {
722 	"wbwd",
723 	wb_methods,
724 	sizeof(struct wb_softc)
725 };
726 
727 static devclass_t wb_devclass;
728 
729 DRIVER_MODULE(wb, isa, wb_isa_driver, wb_devclass, NULL, NULL);
730