xref: /freebsd/sys/dev/ichwd/ichwd.c (revision 119b75925c562202145d7bac7b676b98029c6cb9)
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_PCH,      "Intel PCH watchdog timer",	10 },
114 	{ DEVICEID_PCHM,     "Intel PCH watchdog timer",	10 },
115 	{ DEVICEID_P55,      "Intel P55 watchdog timer",	10 },
116 	{ DEVICEID_PM55,     "Intel PM55 watchdog timer",	10 },
117 	{ DEVICEID_H55,      "Intel H55 watchdog timer",	10 },
118 	{ DEVICEID_QM57,     "Intel QM57 watchdog timer",       10 },
119 	{ DEVICEID_H57,      "Intel H57 watchdog timer",        10 },
120 	{ DEVICEID_HM55,     "Intel HM55 watchdog timer",       10 },
121 	{ DEVICEID_Q57,      "Intel Q57 watchdog timer",        10 },
122 	{ DEVICEID_HM57,     "Intel HM57 watchdog timer",       10 },
123 	{ DEVICEID_PCHMSFF,  "Intel PCHMSFF watchdog timer",    10 },
124 	{ DEVICEID_QS57,     "Intel QS57 watchdog timer",       10 },
125 	{ DEVICEID_3400,     "Intel 3400 watchdog timer",       10 },
126 	{ DEVICEID_3420,     "Intel 3420 watchdog timer",       10 },
127 	{ DEVICEID_3450,     "Intel 3450 watchdog timer",       10 },
128 	{ DEVICEID_CPT0,     "Intel Cougar Point watchdog timer",	10 },
129 	{ DEVICEID_CPT1,     "Intel Cougar Point watchdog timer",	10 },
130 	{ DEVICEID_CPT2,     "Intel Cougar Point watchdog timer",	10 },
131 	{ DEVICEID_CPT3,     "Intel Cougar Point watchdog timer",	10 },
132 	{ DEVICEID_CPT4,     "Intel Cougar Point watchdog timer",	10 },
133 	{ DEVICEID_CPT5,     "Intel Cougar Point watchdog timer",	10 },
134 	{ DEVICEID_CPT6,     "Intel Cougar Point watchdog timer",	10 },
135 	{ DEVICEID_CPT7,     "Intel Cougar Point watchdog timer",	10 },
136 	{ DEVICEID_CPT8,     "Intel Cougar Point watchdog timer",	10 },
137 	{ DEVICEID_CPT9,     "Intel Cougar Point watchdog timer",	10 },
138 	{ DEVICEID_CPT10,    "Intel Cougar Point watchdog timer",	10 },
139 	{ DEVICEID_CPT11,    "Intel Cougar Point watchdog timer",	10 },
140 	{ DEVICEID_CPT12,    "Intel Cougar Point watchdog timer",	10 },
141 	{ DEVICEID_CPT13,    "Intel Cougar Point watchdog timer",	10 },
142 	{ DEVICEID_CPT14,    "Intel Cougar Point watchdog timer",	10 },
143 	{ DEVICEID_CPT15,    "Intel Cougar Point watchdog timer",	10 },
144 	{ DEVICEID_CPT16,    "Intel Cougar Point watchdog timer",	10 },
145 	{ DEVICEID_CPT17,    "Intel Cougar Point watchdog timer",	10 },
146 	{ DEVICEID_CPT18,    "Intel Cougar Point watchdog timer",	10 },
147 	{ DEVICEID_CPT19,    "Intel Cougar Point watchdog timer",	10 },
148 	{ DEVICEID_CPT20,    "Intel Cougar Point watchdog timer",	10 },
149 	{ DEVICEID_CPT21,    "Intel Cougar Point watchdog timer",	10 },
150 	{ DEVICEID_CPT22,    "Intel Cougar Point watchdog timer",	10 },
151 	{ DEVICEID_CPT23,    "Intel Cougar Point watchdog timer",	10 },
152 	{ DEVICEID_CPT23,    "Intel Cougar Point watchdog timer",	10 },
153 	{ DEVICEID_CPT25,    "Intel Cougar Point watchdog timer",	10 },
154 	{ DEVICEID_CPT26,    "Intel Cougar Point watchdog timer",	10 },
155 	{ DEVICEID_CPT27,    "Intel Cougar Point watchdog timer",	10 },
156 	{ DEVICEID_CPT28,    "Intel Cougar Point watchdog timer",	10 },
157 	{ DEVICEID_CPT29,    "Intel Cougar Point watchdog timer",	10 },
158 	{ DEVICEID_CPT30,    "Intel Cougar Point watchdog timer",	10 },
159 	{ DEVICEID_CPT31,    "Intel Cougar Point watchdog timer",	10 },
160 	{ DEVICEID_PATSBURG_LPC1, "Intel Patsburg watchdog timer",	10 },
161 	{ DEVICEID_PATSBURG_LPC2, "Intel Patsburg watchdog timer",	10 },
162 	{ DEVICEID_PPT0,     "Intel Panther Point watchdog timer",	10 },
163 	{ DEVICEID_PPT1,     "Intel Panther Point watchdog timer",	10 },
164 	{ DEVICEID_PPT2,     "Intel Panther Point watchdog timer",	10 },
165 	{ DEVICEID_PPT3,     "Intel Panther Point watchdog timer",	10 },
166 	{ DEVICEID_PPT4,     "Intel Panther Point watchdog timer",	10 },
167 	{ DEVICEID_PPT5,     "Intel Panther Point watchdog timer",	10 },
168 	{ DEVICEID_PPT6,     "Intel Panther Point watchdog timer",	10 },
169 	{ DEVICEID_PPT7,     "Intel Panther Point watchdog timer",	10 },
170 	{ DEVICEID_PPT8,     "Intel Panther Point watchdog timer",	10 },
171 	{ DEVICEID_PPT9,     "Intel Panther Point watchdog timer",	10 },
172 	{ DEVICEID_PPT10,    "Intel Panther Point watchdog timer",	10 },
173 	{ DEVICEID_PPT11,    "Intel Panther Point watchdog timer",	10 },
174 	{ DEVICEID_PPT12,    "Intel Panther Point watchdog timer",	10 },
175 	{ DEVICEID_PPT13,    "Intel Panther Point watchdog timer",	10 },
176 	{ DEVICEID_PPT14,    "Intel Panther Point watchdog timer",	10 },
177 	{ DEVICEID_PPT15,    "Intel Panther Point watchdog timer",	10 },
178 	{ DEVICEID_PPT16,    "Intel Panther Point watchdog timer",	10 },
179 	{ DEVICEID_PPT17,    "Intel Panther Point watchdog timer",	10 },
180 	{ DEVICEID_PPT18,    "Intel Panther Point watchdog timer",	10 },
181 	{ DEVICEID_PPT19,    "Intel Panther Point watchdog timer",	10 },
182 	{ DEVICEID_PPT20,    "Intel Panther Point watchdog timer",	10 },
183 	{ DEVICEID_PPT21,    "Intel Panther Point watchdog timer",	10 },
184 	{ DEVICEID_PPT22,    "Intel Panther Point watchdog timer",	10 },
185 	{ DEVICEID_PPT23,    "Intel Panther Point watchdog timer",	10 },
186 	{ DEVICEID_PPT24,    "Intel Panther Point watchdog timer",	10 },
187 	{ DEVICEID_PPT25,    "Intel Panther Point watchdog timer",	10 },
188 	{ DEVICEID_PPT26,    "Intel Panther Point watchdog timer",	10 },
189 	{ DEVICEID_PPT27,    "Intel Panther Point watchdog timer",	10 },
190 	{ DEVICEID_PPT28,    "Intel Panther Point watchdog timer",	10 },
191 	{ DEVICEID_PPT29,    "Intel Panther Point watchdog timer",	10 },
192 	{ DEVICEID_PPT30,    "Intel Panther Point watchdog timer",	10 },
193 	{ DEVICEID_PPT31,    "Intel Panther Point watchdog timer",	10 },
194 	{ DEVICEID_LPT0,     "Intel Lynx Point watchdog timer",		10 },
195 	{ DEVICEID_LPT1,     "Intel Lynx Point watchdog timer",		10 },
196 	{ DEVICEID_LPT2,     "Intel Lynx Point watchdog timer",		10 },
197 	{ DEVICEID_LPT3,     "Intel Lynx Point watchdog timer",		10 },
198 	{ DEVICEID_LPT4,     "Intel Lynx Point watchdog timer",		10 },
199 	{ DEVICEID_LPT5,     "Intel Lynx Point watchdog timer",		10 },
200 	{ DEVICEID_LPT6,     "Intel Lynx Point watchdog timer",		10 },
201 	{ DEVICEID_LPT7,     "Intel Lynx Point watchdog timer",		10 },
202 	{ DEVICEID_LPT8,     "Intel Lynx Point watchdog timer",		10 },
203 	{ DEVICEID_LPT9,     "Intel Lynx Point watchdog timer",		10 },
204 	{ DEVICEID_LPT10,    "Intel Lynx Point watchdog timer",		10 },
205 	{ DEVICEID_LPT11,    "Intel Lynx Point watchdog timer",		10 },
206 	{ DEVICEID_LPT12,    "Intel Lynx Point watchdog timer",		10 },
207 	{ DEVICEID_LPT13,    "Intel Lynx Point watchdog timer",		10 },
208 	{ DEVICEID_LPT14,    "Intel Lynx Point watchdog timer",		10 },
209 	{ DEVICEID_LPT15,    "Intel Lynx Point watchdog timer",		10 },
210 	{ DEVICEID_LPT16,    "Intel Lynx Point watchdog timer",		10 },
211 	{ DEVICEID_LPT17,    "Intel Lynx Point watchdog timer",		10 },
212 	{ DEVICEID_LPT18,    "Intel Lynx Point watchdog timer",		10 },
213 	{ DEVICEID_LPT19,    "Intel Lynx Point watchdog timer",		10 },
214 	{ DEVICEID_LPT20,    "Intel Lynx Point watchdog timer",		10 },
215 	{ DEVICEID_LPT21,    "Intel Lynx Point watchdog timer",		10 },
216 	{ DEVICEID_LPT22,    "Intel Lynx Point watchdog timer",		10 },
217 	{ DEVICEID_LPT23,    "Intel Lynx Point watchdog timer",		10 },
218 	{ DEVICEID_LPT24,    "Intel Lynx Point watchdog timer",		10 },
219 	{ DEVICEID_LPT25,    "Intel Lynx Point watchdog timer",		10 },
220 	{ DEVICEID_LPT26,    "Intel Lynx Point watchdog timer",		10 },
221 	{ DEVICEID_LPT27,    "Intel Lynx Point watchdog timer",		10 },
222 	{ DEVICEID_LPT28,    "Intel Lynx Point watchdog timer",		10 },
223 	{ DEVICEID_LPT29,    "Intel Lynx Point watchdog timer",		10 },
224 	{ DEVICEID_LPT30,    "Intel Lynx Point watchdog timer",		10 },
225 	{ DEVICEID_LPT31,    "Intel Lynx Point watchdog timer",		10 },
226 	{ DEVICEID_WCPT2,    "Intel Wildcat Point watchdog timer",	10 },
227 	{ DEVICEID_WCPT4,    "Intel Wildcat Point watchdog timer",	10 },
228 	{ DEVICEID_WCPT6,    "Intel Wildcat Point watchdog timer",	10 },
229 	{ DEVICEID_DH89XXCC_LPC,  "Intel DH89xxCC watchdog timer",	10 },
230 	{ DEVICEID_COLETOCRK_LPC, "Intel Coleto Creek watchdog timer",  10 },
231 	{ 0, NULL, 0 },
232 };
233 
234 static devclass_t ichwd_devclass;
235 
236 #define ichwd_read_tco_1(sc, off) \
237 	bus_read_1((sc)->tco_res, (off))
238 #define ichwd_read_tco_2(sc, off) \
239 	bus_read_2((sc)->tco_res, (off))
240 #define ichwd_read_tco_4(sc, off) \
241 	bus_read_4((sc)->tco_res, (off))
242 #define ichwd_read_smi_4(sc, off) \
243 	bus_read_4((sc)->smi_res, (off))
244 #define ichwd_read_gcs_4(sc, off) \
245 	bus_read_4((sc)->gcs_res, (off))
246 
247 #define ichwd_write_tco_1(sc, off, val) \
248 	bus_write_1((sc)->tco_res, (off), (val))
249 #define ichwd_write_tco_2(sc, off, val) \
250 	bus_write_2((sc)->tco_res, (off), (val))
251 #define ichwd_write_tco_4(sc, off, val) \
252 	bus_write_4((sc)->tco_res, (off), (val))
253 #define ichwd_write_smi_4(sc, off, val) \
254 	bus_write_4((sc)->smi_res, (off), (val))
255 #define ichwd_write_gcs_4(sc, off, val) \
256 	bus_write_4((sc)->gcs_res, (off), (val))
257 
258 #define ichwd_verbose_printf(dev, ...) \
259 	do {						\
260 		if (bootverbose)			\
261 			device_printf(dev, __VA_ARGS__);\
262 	} while (0)
263 
264 /*
265  * Disable the watchdog timeout SMI handler.
266  *
267  * Apparently, some BIOSes install handlers that reset or disable the
268  * watchdog timer instead of resetting the system, so we disable the SMI
269  * (by clearing the SMI_TCO_EN bit of the SMI_EN register) to prevent this
270  * from happening.
271  */
272 static __inline void
273 ichwd_smi_disable(struct ichwd_softc *sc)
274 {
275 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) & ~SMI_TCO_EN);
276 }
277 
278 /*
279  * Enable the watchdog timeout SMI handler.  See above for details.
280  */
281 static __inline void
282 ichwd_smi_enable(struct ichwd_softc *sc)
283 {
284 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) | SMI_TCO_EN);
285 }
286 
287 /*
288  * Check if the watchdog SMI triggering is enabled.
289  */
290 static __inline int
291 ichwd_smi_is_enabled(struct ichwd_softc *sc)
292 {
293 	return ((ichwd_read_smi_4(sc, SMI_EN) & SMI_TCO_EN) != 0);
294 }
295 
296 /*
297  * Reset the watchdog status bits.
298  */
299 static __inline void
300 ichwd_sts_reset(struct ichwd_softc *sc)
301 {
302 	/*
303 	 * The watchdog status bits are set to 1 by the hardware to
304 	 * indicate various conditions.  They can be cleared by software
305 	 * by writing a 1, not a 0.
306 	 */
307 	ichwd_write_tco_2(sc, TCO1_STS, TCO_TIMEOUT);
308 	/*
309 	 * According to Intel's docs, clearing SECOND_TO_STS and BOOT_STS must
310 	 * be done in two separate operations.
311 	 */
312 	ichwd_write_tco_2(sc, TCO2_STS, TCO_SECOND_TO_STS);
313 	ichwd_write_tco_2(sc, TCO2_STS, TCO_BOOT_STS);
314 }
315 
316 /*
317  * Enable the watchdog timer by clearing the TCO_TMR_HALT bit in the
318  * TCO1_CNT register.  This is complicated by the need to preserve bit 9
319  * of that same register, and the requirement that all other bits must be
320  * written back as zero.
321  */
322 static __inline void
323 ichwd_tmr_enable(struct ichwd_softc *sc)
324 {
325 	uint16_t cnt;
326 
327 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
328 	ichwd_write_tco_2(sc, TCO1_CNT, cnt & ~TCO_TMR_HALT);
329 	sc->active = 1;
330 	ichwd_verbose_printf(sc->device, "timer enabled\n");
331 }
332 
333 /*
334  * Disable the watchdog timer.  See above for details.
335  */
336 static __inline void
337 ichwd_tmr_disable(struct ichwd_softc *sc)
338 {
339 	uint16_t cnt;
340 
341 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
342 	ichwd_write_tco_2(sc, TCO1_CNT, cnt | TCO_TMR_HALT);
343 	sc->active = 0;
344 	ichwd_verbose_printf(sc->device, "timer disabled\n");
345 }
346 
347 /*
348  * Reload the watchdog timer: writing anything to any of the lower five
349  * bits of the TCO_RLD register reloads the timer from the last value
350  * written to TCO_TMR.
351  */
352 static __inline void
353 ichwd_tmr_reload(struct ichwd_softc *sc)
354 {
355 	if (sc->ich_version <= 5)
356 		ichwd_write_tco_1(sc, TCO_RLD, 1);
357 	else
358 		ichwd_write_tco_2(sc, TCO_RLD, 1);
359 }
360 
361 /*
362  * Set the initial timeout value.  Note that this must always be followed
363  * by a reload.
364  */
365 static __inline void
366 ichwd_tmr_set(struct ichwd_softc *sc, unsigned int timeout)
367 {
368 
369 	if (timeout < TCO_RLD_TMR_MIN)
370 		timeout = TCO_RLD_TMR_MIN;
371 
372 	if (sc->ich_version <= 5) {
373 		uint8_t tmr_val8 = ichwd_read_tco_1(sc, TCO_TMR1);
374 
375 		tmr_val8 &= (~TCO_RLD1_TMR_MAX & 0xff);
376 		if (timeout > TCO_RLD1_TMR_MAX)
377 			timeout = TCO_RLD1_TMR_MAX;
378 		tmr_val8 |= timeout;
379 		ichwd_write_tco_1(sc, TCO_TMR1, tmr_val8);
380 	} else {
381 		uint16_t tmr_val16 = ichwd_read_tco_2(sc, TCO_TMR2);
382 
383 		tmr_val16 &= (~TCO_RLD2_TMR_MAX & 0xffff);
384 		if (timeout > TCO_RLD2_TMR_MAX)
385 			timeout = TCO_RLD2_TMR_MAX;
386 		tmr_val16 |= timeout;
387 		ichwd_write_tco_2(sc, TCO_TMR2, tmr_val16);
388 	}
389 
390 	sc->timeout = timeout;
391 
392 	ichwd_verbose_printf(sc->device, "timeout set to %u ticks\n", timeout);
393 }
394 
395 static __inline int
396 ichwd_clear_noreboot(struct ichwd_softc *sc)
397 {
398 	uint32_t status;
399 	int rc = 0;
400 
401 	/* try to clear the NO_REBOOT bit */
402 	if (sc->ich_version <= 5) {
403 		status = pci_read_config(sc->ich, ICH_GEN_STA, 1);
404 		status &= ~ICH_GEN_STA_NO_REBOOT;
405 		pci_write_config(sc->ich, ICH_GEN_STA, status, 1);
406 		status = pci_read_config(sc->ich, ICH_GEN_STA, 1);
407 		if (status & ICH_GEN_STA_NO_REBOOT)
408 			rc = EIO;
409 	} else {
410 		status = ichwd_read_gcs_4(sc, 0);
411 		status &= ~ICH_GCS_NO_REBOOT;
412 		ichwd_write_gcs_4(sc, 0, status);
413 		status = ichwd_read_gcs_4(sc, 0);
414 		if (status & ICH_GCS_NO_REBOOT)
415 			rc = EIO;
416 	}
417 
418 	if (rc)
419 		device_printf(sc->device,
420 		    "ICH WDT present but disabled in BIOS or hardware\n");
421 
422 	return (rc);
423 }
424 
425 /*
426  * Watchdog event handler - called by the framework to enable or disable
427  * the watchdog or change the initial timeout value.
428  */
429 static void
430 ichwd_event(void *arg, unsigned int cmd, int *error)
431 {
432 	struct ichwd_softc *sc = arg;
433 	unsigned int timeout;
434 
435 	/* convert from power-of-two-ns to WDT ticks */
436 	cmd &= WD_INTERVAL;
437 	timeout = ((uint64_t)1 << cmd) / ICHWD_TICK;
438 	if (cmd) {
439 		if (!sc->active)
440 			ichwd_tmr_enable(sc);
441 		if (timeout != sc->timeout)
442 			ichwd_tmr_set(sc, timeout);
443 		ichwd_tmr_reload(sc);
444 		*error = 0;
445 	} else {
446 		if (sc->active)
447 			ichwd_tmr_disable(sc);
448 	}
449 }
450 
451 static device_t
452 ichwd_find_ich_lpc_bridge(struct ichwd_device **id_p)
453 {
454 	struct ichwd_device *id;
455 	device_t ich = NULL;
456 
457 	/* look for an ICH LPC interface bridge */
458 	for (id = ichwd_devices; id->desc != NULL; ++id)
459 		if ((ich = pci_find_device(VENDORID_INTEL, id->device)) != NULL)
460 			break;
461 
462 	if (ich == NULL)
463 		return (NULL);
464 
465 	ichwd_verbose_printf(ich, "found ICH%d or equivalent chipset: %s\n",
466 	    id->version, id->desc);
467 
468 	if (id_p)
469 		*id_p = id;
470 
471 	return (ich);
472 }
473 
474 /*
475  * Look for an ICH LPC interface bridge.  If one is found, register an
476  * ichwd device.  There can be only one.
477  */
478 static void
479 ichwd_identify(driver_t *driver, device_t parent)
480 {
481 	struct ichwd_device *id_p;
482 	device_t ich = NULL;
483 	device_t dev;
484 	uint32_t rcba;
485 	int rc;
486 
487 	ich = ichwd_find_ich_lpc_bridge(&id_p);
488 	if (ich == NULL)
489 		return;
490 
491 	/* good, add child to bus */
492 	if ((dev = device_find_child(parent, driver->name, 0)) == NULL)
493 		dev = BUS_ADD_CHILD(parent, 0, driver->name, 0);
494 
495 	if (dev == NULL)
496 		return;
497 
498 	device_set_desc_copy(dev, id_p->desc);
499 
500 	if (id_p->version >= 6) {
501 		/* get RCBA (root complex base address) */
502 		rcba = pci_read_config(ich, ICH_RCBA, 4);
503 		rc = bus_set_resource(ich, SYS_RES_MEMORY, 0,
504 		    (rcba & 0xffffc000) + ICH_GCS_OFFSET, ICH_GCS_SIZE);
505 		if (rc)
506 			ichwd_verbose_printf(dev,
507 			    "Can not set memory resource for RCBA\n");
508 	}
509 }
510 
511 static int
512 ichwd_probe(device_t dev)
513 {
514 
515 	/* Do not claim some ISA PnP device by accident. */
516 	if (isa_get_logicalid(dev) != 0)
517 		return (ENXIO);
518 	return (0);
519 }
520 
521 static int
522 ichwd_attach(device_t dev)
523 {
524 	struct ichwd_softc *sc;
525 	struct ichwd_device *id_p;
526 	device_t ich;
527 	unsigned int pmbase = 0;
528 
529 	sc = device_get_softc(dev);
530 	sc->device = dev;
531 
532 	ich = ichwd_find_ich_lpc_bridge(&id_p);
533 	if (ich == NULL) {
534 		device_printf(sc->device, "Can not find ICH device.\n");
535 		goto fail;
536 	}
537 	sc->ich = ich;
538 	sc->ich_version = id_p->version;
539 
540 	/* get ACPI base address */
541 	pmbase = pci_read_config(ich, ICH_PMBASE, 2) & ICH_PMBASE_MASK;
542 	if (pmbase == 0) {
543 		device_printf(dev, "ICH PMBASE register is empty\n");
544 		goto fail;
545 	}
546 
547 	/* allocate I/O register space */
548 	sc->smi_rid = 0;
549 	sc->smi_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->smi_rid,
550 	    pmbase + SMI_BASE, pmbase + SMI_BASE + SMI_LEN - 1, SMI_LEN,
551 	    RF_ACTIVE | RF_SHAREABLE);
552 	if (sc->smi_res == NULL) {
553 		device_printf(dev, "unable to reserve SMI registers\n");
554 		goto fail;
555 	}
556 
557 	sc->tco_rid = 1;
558 	sc->tco_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->tco_rid,
559 	    pmbase + TCO_BASE, pmbase + TCO_BASE + TCO_LEN - 1, TCO_LEN,
560 	    RF_ACTIVE | RF_SHAREABLE);
561 	if (sc->tco_res == NULL) {
562 		device_printf(dev, "unable to reserve TCO registers\n");
563 		goto fail;
564 	}
565 
566 	sc->gcs_rid = 0;
567 	if (sc->ich_version >= 6) {
568 		sc->gcs_res = bus_alloc_resource_any(ich, SYS_RES_MEMORY,
569 		    &sc->gcs_rid, RF_ACTIVE|RF_SHAREABLE);
570 		if (sc->gcs_res == NULL) {
571 			device_printf(dev, "unable to reserve GCS registers\n");
572 			goto fail;
573 		}
574 	}
575 
576 	if (ichwd_clear_noreboot(sc) != 0)
577 		goto fail;
578 
579 	ichwd_verbose_printf(dev, "%s (ICH%d or equivalent)\n",
580 	    device_get_desc(dev), sc->ich_version);
581 
582 	/*
583 	 * Determine if we are coming up after a watchdog-induced reset.  Some
584 	 * BIOSes may clear this bit at bootup, preventing us from reporting
585 	 * this case on such systems.  We clear this bit in ichwd_sts_reset().
586 	 */
587 	if ((ichwd_read_tco_2(sc, TCO2_STS) & TCO_SECOND_TO_STS) != 0)
588 		device_printf(dev,
589 		    "resuming after hardware watchdog timeout\n");
590 
591 	/* reset the watchdog status registers */
592 	ichwd_sts_reset(sc);
593 
594 	/* make sure the WDT starts out inactive */
595 	ichwd_tmr_disable(sc);
596 
597 	/* register the watchdog event handler */
598 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0);
599 
600 	/* disable the SMI handler */
601 	sc->smi_enabled = ichwd_smi_is_enabled(sc);
602 	ichwd_smi_disable(sc);
603 
604 	return (0);
605  fail:
606 	sc = device_get_softc(dev);
607 	if (sc->tco_res != NULL)
608 		bus_release_resource(dev, SYS_RES_IOPORT,
609 		    sc->tco_rid, sc->tco_res);
610 	if (sc->smi_res != NULL)
611 		bus_release_resource(dev, SYS_RES_IOPORT,
612 		    sc->smi_rid, sc->smi_res);
613 	if (sc->gcs_res != NULL)
614 		bus_release_resource(ich, SYS_RES_MEMORY,
615 		    sc->gcs_rid, sc->gcs_res);
616 
617 	return (ENXIO);
618 }
619 
620 static int
621 ichwd_detach(device_t dev)
622 {
623 	struct ichwd_softc *sc;
624 	device_t ich = NULL;
625 
626 	sc = device_get_softc(dev);
627 
628 	/* halt the watchdog timer */
629 	if (sc->active)
630 		ichwd_tmr_disable(sc);
631 
632 	/* enable the SMI handler */
633 	if (sc->smi_enabled != 0)
634 		ichwd_smi_enable(sc);
635 
636 	/* deregister event handler */
637 	if (sc->ev_tag != NULL)
638 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
639 	sc->ev_tag = NULL;
640 
641 	/* reset the watchdog status registers */
642 	ichwd_sts_reset(sc);
643 
644 	/* deallocate I/O register space */
645 	bus_release_resource(dev, SYS_RES_IOPORT, sc->tco_rid, sc->tco_res);
646 	bus_release_resource(dev, SYS_RES_IOPORT, sc->smi_rid, sc->smi_res);
647 
648 	/* deallocate memory resource */
649 	ich = ichwd_find_ich_lpc_bridge(NULL);
650 	if (sc->gcs_res && ich)
651 		bus_release_resource(ich, SYS_RES_MEMORY, sc->gcs_rid, sc->gcs_res);
652 
653 	return (0);
654 }
655 
656 static device_method_t ichwd_methods[] = {
657 	DEVMETHOD(device_identify, ichwd_identify),
658 	DEVMETHOD(device_probe,	ichwd_probe),
659 	DEVMETHOD(device_attach, ichwd_attach),
660 	DEVMETHOD(device_detach, ichwd_detach),
661 	DEVMETHOD(device_shutdown, ichwd_detach),
662 	{0,0}
663 };
664 
665 static driver_t ichwd_driver = {
666 	"ichwd",
667 	ichwd_methods,
668 	sizeof(struct ichwd_softc),
669 };
670 
671 DRIVER_MODULE(ichwd, isa, ichwd_driver, ichwd_devclass, NULL, NULL);
672