1/*-
2 * Copyright (c) 2011 Sandvine Incorporated ULC.
3 * Copyright (c) 2012 iXsystems, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27/*
28 * Support for Winbond watchdog.
29 *
30 * With minor abstractions it might be possible to add support for other
31 * different Winbond Super I/O chips as well.  Winbond seems to have four
32 * different types of chips, four different ways to get into extended config
33 * mode.
34 *
35 * Note: there is no serialization between the debugging sysctl handlers and
36 * the watchdog functions and possibly others poking the registers at the same
37 * time.  For that at least possibly interfering sysctls are hidden by default.
38 */
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD$");
42
43#include <sys/param.h>
44#include <sys/kernel.h>
45#include <sys/systm.h>
46#include <sys/bus.h>
47#include <sys/eventhandler.h>
48#include <sys/lock.h>
49#include <sys/module.h>
50#include <sys/rman.h>
51#include <sys/sbuf.h>
52#include <sys/sysctl.h>
53#include <sys/watchdog.h>
54
55#include <isa/isavar.h>
56
57#include <machine/bus.h>
58#include <machine/resource.h>
59
60/*
61 * Global registers.
62 */
63#define	WB_DEVICE_ID_REG	0x20	/* Device ID */
64#define	WB_DEVICE_REV_REG	0x21	/* Device revision */
65#define	WB_CR26			0x26	/* Bit6: HEFRAS (base port selector) */
66
67/* LDN selection. */
68#define	WB_LDN_REG		0x07
69#define	WB_LDN_REG_LDN8		0x08	/* GPIO 2, Watchdog */
70
71/*
72 * LDN8 (GPIO 2, Watchdog) specific registers and options.
73 */
74/* CR30: LDN8 activation control. */
75#define	WB_LDN8_CR30		0x30
76#define	WB_LDN8_CR30_ACTIVE	0x01	/* 1: LD active */
77
78/* CRF5: Watchdog scale, P20. Mapped to reg_1. */
79#define	WB_LDN8_CRF5		0xF5
80#define	WB_LDN8_CRF5_SCALE	0x08	/* 0: 1s, 1: 60s */
81#define	WB_LDN8_CRF5_KEYB_P20	0x04	/* 1: keyb P20 forces timeout */
82#define	WB_LDN8_CRF5_KBRST	0x02	/* 1: timeout causes pin60 kbd reset */
83
84/* CRF6: Watchdog Timeout (0 == off). Mapped to reg_timeout. */
85#define	WB_LDN8_CRF6		0xF6
86
87/* CRF7: Watchdog mouse, keyb, force, .. Mapped to reg_2. */
88#define	WB_LDN8_CRF7		0xF7
89#define	WB_LDN8_CRF7_MOUSE	0x80	/* 1: mouse irq resets wd timer */
90#define	WB_LDN8_CRF7_KEYB	0x40	/* 1: keyb irq resets wd timer */
91#define	WB_LDN8_CRF7_FORCE	0x20	/* 1: force timeout (self-clear) */
92#define	WB_LDN8_CRF7_TS		0x10	/* 0: counting, 1: fired */
93#define	WB_LDN8_CRF7_IRQS	0x0f	/* irq source for watchdog, 2 == SMI */
94
95enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
96	     w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg,
97	     w83627dhg_p, w83667hg_b, nct6775, nct6776, nct6779, nct6791,
98	     nct6792, nct6102 };
99
100struct wb_softc {
101	device_t		dev;
102	struct resource		*portres;
103	bus_space_tag_t		bst;
104	bus_space_handle_t	bsh;
105	int			rid;
106	eventhandler_tag	ev_tag;
107	int			(*ext_cfg_enter_f)(struct wb_softc *, u_short);
108	void			(*ext_cfg_exit_f)(struct wb_softc *, u_short);
109	enum chips		chip;
110	uint8_t			ctl_reg;
111	uint8_t			time_reg;
112	uint8_t			csr_reg;
113	int			debug_verbose;
114
115	/*
116	 * Special feature to let the watchdog fire at a different
117	 * timeout as set by watchdog(4) but still use that API to
118	 * re-load it periodically.
119	 */
120	unsigned int		timeout_override;
121
122	/*
123	 * Space to save current state temporary and for sysctls.
124	 * We want to know the timeout value and usually need two
125	 * additional registers for options. Do not name them by
126	 * register as these might be different by chip.
127	 */
128	uint8_t			reg_timeout;
129	uint8_t			reg_1;
130	uint8_t			reg_2;
131};
132
133static int	ext_cfg_enter_0x87_0x87(struct wb_softc *, u_short);
134static void	ext_cfg_exit_0xaa(struct wb_softc *, u_short);
135
136struct winbond_superio_cfg {
137	uint8_t			efer;	/* and efir */
138	int			(*ext_cfg_enter_f)(struct wb_softc *, u_short);
139	void			(*ext_cfg_exit_f)(struct wb_softc *, u_short);
140} probe_addrs[] = {
141	{
142		.efer			= 0x2e,
143		.ext_cfg_enter_f	= ext_cfg_enter_0x87_0x87,
144		.ext_cfg_exit_f		= ext_cfg_exit_0xaa,
145	},
146	{
147		.efer			= 0x4e,
148		.ext_cfg_enter_f	= ext_cfg_enter_0x87_0x87,
149		.ext_cfg_exit_f		= ext_cfg_exit_0xaa,
150	},
151};
152
153struct winbond_vendor_device_id {
154	uint8_t			device_id;
155	enum chips		chip;
156	const char *		descr;
157} wb_devs[] = {
158	{
159		.device_id	= 0x52,
160		.chip		= w83627hf,
161		.descr		= "Winbond 83627HF/F/HG/G",
162	},
163	{
164		.device_id	= 0x59,
165		.chip		= w83627s,
166		.descr		= "Winbond 83627S",
167	},
168	{
169		.device_id	= 0x60,
170		.chip		= w83697hf,
171		.descr		= "Winbond 83697HF",
172	},
173	{
174		.device_id	= 0x68,
175		.chip		= w83697ug,
176		.descr		= "Winbond 83697UG",
177	},
178	{
179		.device_id	= 0x70,
180		.chip		= w83637hf,
181		.descr		= "Winbond 83637HF",
182	},
183	{
184		.device_id	= 0x82,
185		.chip		= w83627thf,
186		.descr		= "Winbond 83627THF",
187	},
188	{
189		.device_id	= 0x85,
190		.chip		= w83687thf,
191		.descr		= "Winbond 83687THF",
192	},
193	{
194		.device_id	= 0x88,
195		.chip		= w83627ehf,
196		.descr		= "Winbond 83627EHF",
197	},
198	{
199		.device_id	= 0xa0,
200		.chip		= w83627dhg,
201		.descr		= "Winbond 83627DHG",
202	},
203	{
204		.device_id	= 0xa2,
205		.chip		= w83627uhg,
206		.descr		= "Winbond 83627UHG",
207	},
208	{
209		.device_id	= 0xa5,
210		.chip		= w83667hg,
211		.descr		= "Winbond 83667HG",
212	},
213	{
214		.device_id	= 0xb0,
215		.chip		= w83627dhg_p,
216		.descr		= "Winbond 83627DHG-P",
217	},
218	{
219		.device_id	= 0xb3,
220		.chip		= w83667hg_b,
221		.descr		= "Winbond 83667HG-B",
222	},
223	{
224		.device_id	= 0xb4,
225		.chip		= nct6775,
226		.descr		= "Nuvoton NCT6775",
227	},
228	{
229		.device_id	= 0xc3,
230		.chip		= nct6776,
231		.descr		= "Nuvoton NCT6776",
232	},
233	{
234		.device_id	= 0xc4,
235		.chip		= nct6102,
236		.descr		= "Nuvoton NCT6102",
237	},
238	{
239		.device_id	= 0xc5,
240		.chip		= nct6779,
241		.descr		= "Nuvoton NCT6779",
242	},
243	{
244		.device_id	= 0xc8,
245		.chip		= nct6791,
246		.descr		= "Nuvoton NCT6791",
247	},
248	{
249		.device_id	= 0xc9,
250		.chip		= nct6792,
251		.descr		= "Nuvoton NCT6792",
252	},
253};
254
255static void
256write_efir_1(struct wb_softc *sc, u_short baseport, uint8_t value)
257{
258
259	MPASS(sc != NULL || baseport != 0);
260	if (sc != NULL)
261		bus_space_write_1((sc)->bst, (sc)->bsh, 0, (value));
262	else
263		outb(baseport, value);
264}
265
266static uint8_t __unused
267read_efir_1(struct wb_softc *sc, u_short baseport)
268{
269
270	MPASS(sc != NULL || baseport != 0);
271	if (sc != NULL)
272		return (bus_space_read_1((sc)->bst, (sc)->bsh, 0));
273	else
274		return (inb(baseport));
275}
276
277static void
278write_efdr_1(struct wb_softc *sc, u_short baseport, uint8_t value)
279{
280
281	MPASS(sc != NULL || baseport != 0);
282	if (sc != NULL)
283		bus_space_write_1((sc)->bst, (sc)->bsh, 1, (value));
284	else
285		outb(baseport + 1, value);
286}
287
288static uint8_t
289read_efdr_1(struct wb_softc *sc, u_short baseport)
290{
291
292	MPASS(sc != NULL || baseport != 0);
293	if (sc != NULL)
294		return (bus_space_read_1((sc)->bst, (sc)->bsh, 1));
295	else
296		return (inb(baseport + 1));
297}
298
299static void
300write_reg(struct wb_softc *sc, uint8_t reg, uint8_t value)
301{
302
303	write_efir_1(sc, 0, reg);
304	write_efdr_1(sc, 0, value);
305}
306
307static uint8_t
308read_reg(struct wb_softc *sc, uint8_t reg)
309{
310
311	write_efir_1(sc, 0, reg);
312	return (read_efdr_1(sc, 0));
313}
314
315/*
316 * Return the watchdog related registers as we last read them.  This will
317 * usually not give the current timeout or state on whether the watchdog
318 * fired.
319 */
320static int
321sysctl_wb_debug(SYSCTL_HANDLER_ARGS)
322{
323	struct wb_softc *sc;
324	struct sbuf sb;
325	int error;
326
327	sc = arg1;
328
329	sbuf_new_for_sysctl(&sb, NULL, 64, req);
330
331	sbuf_printf(&sb, "LDN8 (GPIO2, Watchdog): ");
332	sbuf_printf(&sb, "CR%02X 0x%02x ", sc->ctl_reg, sc->reg_1);
333	sbuf_printf(&sb, "CR%02X 0x%02x ", sc->time_reg, sc->reg_timeout);
334	sbuf_printf(&sb, "CR%02X 0x%02x", sc->csr_reg, sc->reg_2);
335
336	error = sbuf_finish(&sb);
337	sbuf_delete(&sb);
338	return (error);
339}
340
341/*
342 * Read the current values before returning them.  Given this might poke
343 * the registers the same time as the watchdog, this sysctl handler should
344 * be marked CTLFLAG_SKIP to not show up by default.
345 */
346static int
347sysctl_wb_debug_current(SYSCTL_HANDLER_ARGS)
348{
349	struct wb_softc *sc;
350
351	sc = arg1;
352
353	if ((*sc->ext_cfg_enter_f)(sc, 0) != 0)
354		return (ENXIO);
355
356	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
357	write_reg(sc, WB_LDN_REG, WB_LDN_REG_LDN8);
358
359	sc->reg_1 = read_reg(sc, sc->ctl_reg);
360	sc->reg_timeout = read_reg(sc, sc->time_reg);
361	sc->reg_2 = read_reg(sc, sc->csr_reg);
362
363	(*sc->ext_cfg_exit_f)(sc, 0);
364
365	return (sysctl_wb_debug(oidp, arg1, arg2, req));
366}
367
368/*
369 * Sysctl handlers to force a watchdog timeout or to test the NMI functionality
370 * works as expetced.
371 * For testing we could set a test_nmi flag in the softc that, in case of NMI, a
372 * callback function from trap.c could check whether we fired and not report the
373 * timeout but clear the flag for the sysctl again.  This is interesting given a
374 * lot of boards have jumpers to change the action on watchdog timeout or
375 * disable the watchdog completely.
376 * XXX-BZ notyet: currently no general infrastructure exists to do this.
377 */
378static int
379sysctl_wb_force_test_nmi(SYSCTL_HANDLER_ARGS)
380{
381	struct wb_softc *sc;
382	int error, test, val;
383
384	sc = arg1;
385	test = arg2;
386
387#ifdef notyet
388	val = sc->test_nmi;
389#else
390	val = 0;
391#endif
392	error = sysctl_handle_int(oidp, &val, 0, req);
393        if (error || !req->newptr)
394                return (error);
395
396#ifdef notyet
397	/* Manually clear the test for a value of 0 and do nothing else. */
398	if (test && val == 0) {
399		sc->test_nmi = 0;
400		return (0);
401	}
402#endif
403
404	if ((*sc->ext_cfg_enter_f)(sc, 0) != 0)
405		return (ENXIO);
406
407#ifdef notyet
408	/*
409	 * If we are testing the NMI functionality, set the flag before
410	 * forcing the timeout.
411	 */
412	if (test)
413		sc->test_nmi = 1;
414#endif
415
416	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
417	write_reg(sc, WB_LDN_REG, WB_LDN_REG_LDN8);
418
419	/* Force watchdog to fire. */
420	sc->reg_2 = read_reg(sc, sc->csr_reg);
421	sc->reg_2 |= WB_LDN8_CRF7_FORCE;
422	write_reg(sc, sc->csr_reg, sc->reg_2);
423
424	(*sc->ext_cfg_exit_f)(sc, 0);
425
426	return (0);
427}
428
429/*
430 * Print current watchdog state.
431 *
432 * Note: it is the responsibility of the caller to update the registers
433 * upfront.
434 */
435static void
436wb_print_state(struct wb_softc *sc, const char *msg)
437{
438
439	device_printf(sc->dev, "%s%sWatchdog %sabled. %s"
440	    "Scaling by %ds, timer at %d (%s=%ds%s). "
441	    "CRF5 0x%02x CRF7 0x%02x\n",
442	    (msg != NULL) ? msg : "", (msg != NULL) ? ": " : "",
443	    (sc->reg_timeout > 0x00) ? "en" : "dis",
444	    (sc->reg_2 & WB_LDN8_CRF7_TS) ? "Watchdog fired. " : "",
445	    (sc->reg_1 & WB_LDN8_CRF5_SCALE) ? 60 : 1,
446	    sc->reg_timeout,
447	    (sc->reg_timeout > 0x00) ? "<" : "",
448	    sc->reg_timeout * ((sc->reg_1 & WB_LDN8_CRF5_SCALE) ? 60 : 1),
449	    (sc->reg_timeout > 0x00) ? " left" : "",
450	    sc->reg_1, sc->reg_2);
451}
452
453/*
454 * Functions to enter and exit extended function mode.  Possibly shared
455 * between different chips.
456 */
457static int
458ext_cfg_enter_0x87_0x87(struct wb_softc *sc, u_short baseport)
459{
460
461	/*
462	 * Enable extended function mode.
463	 * Winbond does not allow us to validate so always return success.
464	 */
465	write_efir_1(sc, baseport, 0x87);
466	write_efir_1(sc, baseport, 0x87);
467
468	return (0);
469}
470
471static void
472ext_cfg_exit_0xaa(struct wb_softc *sc, u_short baseport)
473{
474
475	write_efir_1(sc, baseport, 0xaa);
476}
477
478/*
479 * (Re)load the watchdog counter depending on timeout.  A timeout of 0 will
480 * disable the watchdog.
481 */
482static int
483wb_set_watchdog(struct wb_softc *sc, unsigned int timeout)
484{
485
486	if (timeout != 0) {
487		/*
488		 * In case an override is set, let it override.  It may lead
489		 * to strange results as we do not check the input of the sysctl.
490		 */
491		if (sc->timeout_override > 0)
492			timeout = sc->timeout_override;
493
494		/* Make sure we support the requested timeout. */
495		if (timeout > 255 * 60)
496			return (EINVAL);
497	}
498
499	if (sc->debug_verbose)
500		wb_print_state(sc, "Before watchdog counter (re)load");
501
502	if ((*sc->ext_cfg_enter_f)(sc, 0) != 0)
503		return (ENXIO);
504
505	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog) */
506	write_reg(sc, WB_LDN_REG, WB_LDN_REG_LDN8);
507
508	if (timeout == 0) {
509		/* Disable watchdog. */
510		sc->reg_timeout = 0;
511		write_reg(sc, sc->time_reg, sc->reg_timeout);
512
513	} else {
514		/* Read current scaling factor. */
515		sc->reg_1 = read_reg(sc, sc->ctl_reg);
516
517		if (timeout > 255) {
518			/* Set scaling factor to 60s. */
519			sc->reg_1 |= WB_LDN8_CRF5_SCALE;
520			sc->reg_timeout = (timeout / 60);
521			if (timeout % 60)
522				sc->reg_timeout++;
523		} else {
524			/* Set scaling factor to 1s. */
525			sc->reg_1 &= ~WB_LDN8_CRF5_SCALE;
526			sc->reg_timeout = timeout;
527		}
528
529		/* In case we fired before we need to clear to fire again. */
530		sc->reg_2 = read_reg(sc, sc->csr_reg);
531		if (sc->reg_2 & WB_LDN8_CRF7_TS) {
532			sc->reg_2 &= ~WB_LDN8_CRF7_TS;
533			write_reg(sc, sc->csr_reg, sc->reg_2);
534		}
535
536		/* Write back scaling factor. */
537		write_reg(sc, sc->ctl_reg, sc->reg_1);
538
539		/* Set timer and arm/reset the watchdog. */
540		write_reg(sc, sc->time_reg, sc->reg_timeout);
541	}
542
543	(*sc->ext_cfg_exit_f)(sc, 0);
544
545	if (sc->debug_verbose)
546		wb_print_state(sc, "After watchdog counter (re)load");
547	return (0);
548}
549
550/*
551 * watchdog(9) EVENTHANDLER function implementation to (re)load the counter
552 * with the given timeout or disable the watchdog.
553 */
554static void
555wb_watchdog_fn(void *private, u_int cmd, int *error)
556{
557	struct wb_softc *sc;
558	unsigned int timeout;
559	int e;
560
561	sc = private;
562	KASSERT(sc != NULL, ("%s: watchdog handler function called without "
563	    "softc.", __func__));
564
565	cmd &= WD_INTERVAL;
566	if (cmd > 0 && cmd <= 63) {
567		/* Reset (and arm) watchdog. */
568		timeout = ((uint64_t)1 << cmd) / 1000000000;
569		if (timeout == 0)
570			timeout = 1;
571		e = wb_set_watchdog(sc, timeout);
572		if (e == 0) {
573			if (error != NULL)
574				*error = 0;
575		} else {
576			/* On error, try to make sure the WD is disabled. */
577			wb_set_watchdog(sc, 0);
578		}
579
580	} else {
581		/* Disable watchdog. */
582		e = wb_set_watchdog(sc, 0);
583		if (e != 0 && cmd == 0 && error != NULL) {
584			/* Failed to disable watchdog. */
585			*error = EOPNOTSUPP;
586		}
587	}
588}
589
590/*
591 * Probe/attach the Winbond Super I/O chip.
592 *
593 * Initial abstraction to possibly support more chips:
594 * - Iterate over the well known base ports, try to enable extended function
595 *   mode and read and match the device ID and device revision.  Unfortunately
596 *   the Vendor ID is in the hardware monitoring section accessible by different
597 *   base ports only.
598 * - Also HEFRAS, which would tell use the base port, is only accessible after
599 *   entering extended function mode, for which the base port is needed.
600 *   At least check HEFRAS to match the current base port we are probing.
601 * - On match set the description, remember functions to enter/exit extended
602 *   function mode as well as the base port.
603 */
604static int
605wb_probe_enable(device_t dev, int probe)
606{
607	struct wb_softc *sc;
608	int error, found, i, j;
609	uint8_t dev_id, dev_rev, cr26;
610	char buf[128];
611
612	if (dev == NULL)
613		sc = NULL;
614	else {
615		sc = device_get_softc(dev);
616		bzero(sc, sizeof(*sc));
617		sc->dev = dev;
618	}
619
620	error = ENXIO;
621	found = 0;
622	for (i = 0; i < sizeof(probe_addrs) / sizeof(*probe_addrs); i++) {
623
624		if (sc != NULL) {
625			/* Allocate bus resources for IO index/data register access. */
626			sc->portres = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->rid,
627			    probe_addrs[i].efer, probe_addrs[i].efer + 1, 2, RF_ACTIVE);
628			if (sc->portres == NULL)
629				continue;
630			sc->bst = rman_get_bustag(sc->portres);
631			sc->bsh = rman_get_bushandle(sc->portres);
632		}
633
634		error = (*probe_addrs[i].ext_cfg_enter_f)(sc, probe_addrs[i].efer);
635		if (error != 0)
636			goto cleanup;
637
638		/* Identify the SuperIO chip. */
639		write_efir_1(sc, probe_addrs[i].efer, WB_DEVICE_ID_REG);
640		dev_id = read_efdr_1(sc, probe_addrs[i].efer);
641		write_efir_1(sc, probe_addrs[i].efer, WB_DEVICE_REV_REG);
642		dev_rev = read_efdr_1(sc, probe_addrs[i].efer);
643		write_efir_1(sc, probe_addrs[i].efer, WB_CR26);
644		cr26 = read_efdr_1(sc, probe_addrs[i].efer);
645
646		if (dev_id == 0xff && dev_rev == 0xff)
647			goto cleanup;
648
649		/* HEFRAS of 0 means EFER at 0x2e, 1 means EFER at 0x4e. */
650		if (((cr26 & 0x40) == 0x00 && probe_addrs[i].efer != 0x2e) ||
651		    ((cr26 & 0x40) == 0x40 && probe_addrs[i].efer != 0x4e)) {
652			if (dev != NULL)
653				device_printf(dev, "HEFRAS and EFER do not "
654				    "align: EFER 0x%02x DevID 0x%02x DevRev "
655				    "0x%02x CR26 0x%02x\n",
656				    probe_addrs[i].efer, dev_id, dev_rev, cr26);
657			goto cleanup;
658		}
659
660		for (j = 0; j < sizeof(wb_devs) / sizeof(*wb_devs); j++) {
661			if (wb_devs[j].device_id == dev_id) {
662				found = 1;
663				break;
664			}
665		}
666
667		if (probe && dev != NULL) {
668			snprintf(buf, sizeof(buf),
669			    "%s (0x%02x/0x%02x) Watchdog Timer",
670			    found ? wb_devs[j].descr :
671			     "Unknown Winbond/Nuvoton", dev_id, dev_rev);
672			device_set_desc_copy(dev, buf);
673		}
674
675		/* If this is hinted attach, try to guess the model. */
676		if (dev != NULL && !found) {
677			found = 1;
678			j = 0;
679		}
680
681cleanup:
682		if (probe || !found) {
683			(*probe_addrs[i].ext_cfg_exit_f)(sc, probe_addrs[i].efer);
684			if (sc != NULL)
685				(void) bus_release_resource(dev, SYS_RES_IOPORT,
686				    sc->rid, sc->portres);
687		}
688
689		/*
690		 * Stop probing if have successfully identified the SuperIO.
691		 * Remember the extended function mode enter/exit functions
692		 * for operations.
693		 */
694		if (found) {
695			if (sc != NULL) {
696				sc->ext_cfg_enter_f = probe_addrs[i].ext_cfg_enter_f;
697				sc->ext_cfg_exit_f = probe_addrs[i].ext_cfg_exit_f;
698				sc->chip = wb_devs[j].chip;
699				sc->ctl_reg = 0xf5;
700				sc->time_reg = 0xf6;
701				sc->csr_reg = 0xf7;
702				if (sc->chip == w83697hf ||
703				    sc->chip == w83697ug) {
704					sc->ctl_reg = 0xf3;
705					sc->time_reg = 0xf4;
706				} else if (sc->chip == nct6102) {
707					sc->ctl_reg = 0xf0;
708					sc->time_reg = 0xf1;
709					sc->csr_reg = 0xf2;
710				}
711			}
712			return (BUS_PROBE_SPECIFIC);
713		} else
714			error = ENXIO;
715	}
716
717	return (error);
718}
719
720static void
721wb_identify(driver_t *driver, device_t parent)
722{
723
724	if (device_find_child(parent, driver->name, 0) == NULL) {
725		if (wb_probe_enable(NULL, 1) <= 0)
726			BUS_ADD_CHILD(parent, 0, driver->name, 0);
727	}
728}
729
730static int
731wb_probe(device_t dev)
732{
733
734	/* Make sure we do not claim some ISA PNP device. */
735	if (isa_get_logicalid(dev) != 0)
736		return (ENXIO);
737
738	return (wb_probe_enable(dev, 1));
739}
740
741static int
742wb_attach(device_t dev)
743{
744	struct wb_softc *sc;
745	struct sysctl_ctx_list *sctx;
746	struct sysctl_oid *soid;
747	unsigned long timeout;
748	int error;
749	uint8_t t;
750
751	error = wb_probe_enable(dev, 0);
752	if (error > 0)
753		return (ENXIO);
754
755	sc = device_get_softc(dev);
756	KASSERT(sc->ext_cfg_enter_f != NULL && sc->ext_cfg_exit_f != NULL,
757	    ("%s: successful probe result but not setup correctly", __func__));
758
759	/* Watchdog is configured as part of LDN 8 (GPIO Port2, Watchdog). */
760	write_reg(sc, WB_LDN_REG, WB_LDN_REG_LDN8);
761
762	/* Make sure WDT is enabled. */
763	write_reg(sc, WB_LDN8_CR30,
764	    read_reg(sc, WB_LDN8_CR30) | WB_LDN8_CR30_ACTIVE);
765
766	switch (sc->chip) {
767	case w83627hf:
768	case w83627s:
769		t = read_reg(sc, 0x2B) & ~0x10;
770		write_reg(sc, 0x2B, t); /* set GPIO24 to WDT0 */
771		break;
772	case w83697hf:
773		/* Set pin 119 to WDTO# mode (= CR29, WDT0) */
774		t = read_reg(sc, 0x29) & ~0x60;
775		t |= 0x20;
776		write_reg(sc, 0x29, t);
777		break;
778	case w83697ug:
779		/* Set pin 118 to WDTO# mode */
780		t = read_reg(sc, 0x2b) & ~0x04;
781		write_reg(sc, 0x2b, t);
782		break;
783	case w83627thf:
784		t = (read_reg(sc, 0x2B) & ~0x08) | 0x04;
785		write_reg(sc, 0x2B, t); /* set GPIO3 to WDT0 */
786		break;
787	case w83627dhg:
788	case w83627dhg_p:
789		t = read_reg(sc, 0x2D) & ~0x01; /* PIN77 -> WDT0# */
790		write_reg(sc, 0x2D, t); /* set GPIO5 to WDT0 */
791		t = read_reg(sc, sc->ctl_reg);
792		t |= 0x02;	/* enable the WDTO# output low pulse
793				 * to the KBRST# pin */
794		write_reg(sc, sc->ctl_reg, t);
795		break;
796	case w83637hf:
797		break;
798	case w83687thf:
799		t = read_reg(sc, 0x2C) & ~0x80; /* PIN47 -> WDT0# */
800		write_reg(sc, 0x2C, t);
801		break;
802	case w83627ehf:
803	case w83627uhg:
804	case w83667hg:
805	case w83667hg_b:
806	case nct6775:
807	case nct6776:
808	case nct6779:
809	case nct6791:
810	case nct6792:
811	case nct6102:
812		/*
813		 * These chips have a fixed WDTO# output pin (W83627UHG),
814		 * or support more than one WDTO# output pin.
815		 * Don't touch its configuration, and hope the BIOS
816		 * does the right thing.
817		 */
818		t = read_reg(sc, sc->ctl_reg);
819		t |= 0x02;	/* enable the WDTO# output low pulse
820				 * to the KBRST# pin */
821		write_reg(sc, sc->ctl_reg, t);
822		break;
823	default:
824		break;
825	}
826
827	/* Read the current watchdog configuration. */
828	sc->reg_1 = read_reg(sc, sc->ctl_reg);
829	sc->reg_timeout = read_reg(sc, sc->time_reg);
830	sc->reg_2 = read_reg(sc, sc->csr_reg);
831
832	/* Print current state if bootverbose or watchdog already enabled. */
833	if (bootverbose || (sc->reg_timeout > 0x00))
834		wb_print_state(sc, "Before watchdog attach");
835
836	sc->reg_1 &= ~WB_LDN8_CRF5_KEYB_P20;
837	sc->reg_1 |= WB_LDN8_CRF5_KBRST;
838	write_reg(sc, sc->ctl_reg, sc->reg_1);
839
840	/*
841	 * Clear a previous watchdog timeout event (if still set).
842	 * Disable timer reset on mouse interrupts.  Leave reset on keyboard,
843	 * since one of my boards is getting stuck in reboot without it.
844	 */
845	sc->reg_2 &= ~(WB_LDN8_CRF7_MOUSE|WB_LDN8_CRF7_TS);
846	write_reg(sc, sc->csr_reg, sc->reg_2);
847
848	(*sc->ext_cfg_exit_f)(sc, 0);
849
850	/* Read global timeout override tunable, Add per device sysctls. */
851	if (TUNABLE_ULONG_FETCH("hw.wbwd.timeout_override", &timeout)) {
852		if (timeout > 0)
853			sc->timeout_override = timeout;
854	}
855	sctx = device_get_sysctl_ctx(dev);
856	soid = device_get_sysctl_tree(dev);
857        SYSCTL_ADD_UINT(sctx, SYSCTL_CHILDREN(soid), OID_AUTO,
858	    "timeout_override", CTLFLAG_RW, &sc->timeout_override, 0,
859            "Timeout in seconds overriding default watchdog timeout");
860        SYSCTL_ADD_INT(sctx, SYSCTL_CHILDREN(soid), OID_AUTO,
861	    "debug_verbose", CTLFLAG_RW, &sc->debug_verbose, 0,
862            "Enables extra debugging information");
863        SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "debug",
864	    CTLTYPE_STRING|CTLFLAG_RD, sc, 0, sysctl_wb_debug, "A",
865            "Selected register information from last change by driver");
866        SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "debug_current",
867	    CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_SKIP, sc, 0,
868	     sysctl_wb_debug_current, "A",
869	     "Selected register information (may interfere)");
870	SYSCTL_ADD_PROC(sctx, SYSCTL_CHILDREN(soid), OID_AUTO, "force_timeout",
871	    CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_SKIP, sc, 0,
872	    sysctl_wb_force_test_nmi, "I", "Enable to force watchdog to fire.");
873
874	/* Register watchdog. */
875	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, wb_watchdog_fn, sc,
876	    0);
877
878	if (bootverbose)
879		wb_print_state(sc, "After watchdog attach");
880
881	return (0);
882}
883
884static int
885wb_detach(device_t dev)
886{
887	struct wb_softc *sc;
888
889	sc = device_get_softc(dev);
890
891	/* Unregister and stop the watchdog if running. */
892	if (sc->ev_tag)
893		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
894	wb_set_watchdog(sc, 0);
895
896	/* Disable extended function mode. */
897	(*sc->ext_cfg_exit_f)(sc, 0);
898
899	/* Cleanup resources. */
900	(void) bus_release_resource(dev, SYS_RES_IOPORT, sc->rid, sc->portres);
901
902	/* Bus subroutines take care of sysctls already. */
903
904	return (0);
905}
906
907static device_method_t wb_methods[] = {
908	/* Device interface */
909	DEVMETHOD(device_identify,	wb_identify),
910	DEVMETHOD(device_probe,		wb_probe),
911	DEVMETHOD(device_attach,	wb_attach),
912	DEVMETHOD(device_detach,	wb_detach),
913
914	DEVMETHOD_END
915};
916
917static driver_t wb_isa_driver = {
918	"wbwd",
919	wb_methods,
920	sizeof(struct wb_softc)
921};
922
923static devclass_t wb_devclass;
924
925DRIVER_MODULE(wb, isa, wb_isa_driver, wb_devclass, NULL, NULL);
926