xref: /freebsd/sys/dev/ichwd/ichwd.c (revision f6c0136c7fb87ab8277221a306291e386fe944fb)
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 
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
58 
59 #include <sys/param.h>
60 #include <sys/kernel.h>
61 #include <sys/module.h>
62 #include <sys/systm.h>
63 #include <sys/bus.h>
64 #include <machine/bus.h>
65 #include <sys/rman.h>
66 #include <machine/resource.h>
67 #include <sys/watchdog.h>
68 
69 #include <dev/pci/pcivar.h>
70 
71 #include <dev/ichwd/ichwd.h>
72 
73 static struct ichwd_device ichwd_devices[] = {
74 	{ VENDORID_INTEL, DEVICEID_82801AA, "Intel 82801AA watchdog timer" },
75 	{ VENDORID_INTEL, DEVICEID_82801AB, "Intel 82801AB watchdog timer" },
76 	{ VENDORID_INTEL, DEVICEID_82801BA, "Intel 82801BA watchdog timer" },
77 	{ VENDORID_INTEL, DEVICEID_82801BAM, "Intel 82801BAM watchdog timer" },
78 	{ VENDORID_INTEL, DEVICEID_82801CA, "Intel 82801CA watchdog timer" },
79 	{ VENDORID_INTEL, DEVICEID_82801CAM, "Intel 82801CAM watchdog timer" },
80 	{ VENDORID_INTEL, DEVICEID_82801DB, "Intel 82801DB watchdog timer" },
81 	{ VENDORID_INTEL, DEVICEID_82801DBM, "Intel 82801DBM watchdog timer" },
82 	{ VENDORID_INTEL, DEVICEID_82801E, "Intel 82801E watchdog timer" },
83 	{ VENDORID_INTEL, DEVICEID_82801EBR, "Intel 82801EB/ER watchdog timer" },
84 	{ VENDORID_INTEL, DEVICEID_82801FBR, "Intel 82801FB/FR watchdog timer" },
85 	{ VENDORID_INTEL, DEVICEID_ICH5, "Intel ICH5 watchdog timer"},
86 	{ VENDORID_INTEL, DEVICEID_6300ESB, "Intel 6300ESB watchdog timer"},
87 	{ 0, 0, NULL },
88 };
89 
90 static devclass_t ichwd_devclass;
91 
92 #define ichwd_read_tco_1(sc, off) \
93 	bus_space_read_1((sc)->tco_bst, (sc)->tco_bsh, (off))
94 #define ichwd_read_tco_2(sc, off) \
95 	bus_space_read_2((sc)->tco_bst, (sc)->tco_bsh, (off))
96 #define ichwd_read_tco_4(sc, off) \
97 	bus_space_read_4((sc)->tco_bst, (sc)->tco_bsh, (off))
98 
99 #define ichwd_write_tco_1(sc, off, val) \
100 	bus_space_write_1((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
101 #define ichwd_write_tco_2(sc, off, val) \
102 	bus_space_write_2((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
103 #define ichwd_write_tco_4(sc, off, val) \
104 	bus_space_write_4((sc)->tco_bst, (sc)->tco_bsh, (off), (val))
105 
106 #define ichwd_read_smi_4(sc, off) \
107 	bus_space_read_4((sc)->smi_bst, (sc)->smi_bsh, (off))
108 #define ichwd_write_smi_4(sc, off, val) \
109 	bus_space_write_4((sc)->smi_bst, (sc)->smi_bsh, (off), (val))
110 
111 static __inline void
112 ichwd_intr_enable(struct ichwd_softc *sc)
113 {
114 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) & ~SMI_TCO_EN);
115 }
116 
117 static __inline void
118 ichwd_intr_disable(struct ichwd_softc *sc)
119 {
120 	ichwd_write_smi_4(sc, SMI_EN, ichwd_read_smi_4(sc, SMI_EN) | SMI_TCO_EN);
121 }
122 
123 static __inline void
124 ichwd_sts_reset(struct ichwd_softc *sc)
125 {
126 	ichwd_write_tco_2(sc, TCO1_STS, TCO_TIMEOUT);
127 	ichwd_write_tco_2(sc, TCO2_STS, TCO_BOOT_STS);
128 	ichwd_write_tco_2(sc, TCO2_STS, TCO_SECOND_TO_STS);
129 }
130 
131 static __inline void
132 ichwd_tmr_enable(struct ichwd_softc *sc)
133 {
134 	uint16_t cnt;
135 
136 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
137 	ichwd_write_tco_2(sc, TCO1_CNT, cnt & ~TCO_TMR_HALT);
138 	sc->active = 1;
139 	if (bootverbose)
140 		device_printf(sc->device, "timer enabled\n");
141 }
142 
143 static __inline void
144 ichwd_tmr_disable(struct ichwd_softc *sc)
145 {
146 	uint16_t cnt;
147 
148 	cnt = ichwd_read_tco_2(sc, TCO1_CNT) & TCO_CNT_PRESERVE;
149 	ichwd_write_tco_2(sc, TCO1_CNT, cnt | TCO_TMR_HALT);
150 	sc->active = 0;
151 	if (bootverbose)
152 		device_printf(sc->device, "timer disabled\n");
153 }
154 
155 static __inline void
156 ichwd_tmr_reload(struct ichwd_softc *sc)
157 {
158 	ichwd_write_tco_1(sc, TCO_RLD, 1);
159 	if (bootverbose)
160 		device_printf(sc->device, "timer reloaded\n");
161 }
162 
163 static __inline void
164 ichwd_tmr_set(struct ichwd_softc *sc, uint8_t timeout)
165 {
166 	ichwd_write_tco_1(sc, TCO_TMR, timeout);
167 	sc->timeout = timeout;
168 	if (bootverbose)
169 		device_printf(sc->device, "timeout set to %u ticks\n", timeout);
170 }
171 
172 /*
173  * Watchdog event handler.
174  */
175 static void
176 ichwd_event(void *arg, unsigned int cmd, int *error)
177 {
178 	struct ichwd_softc *sc = arg;
179 	unsigned int timeout;
180 
181 	/* convert from power-of-two-ns to WDT ticks */
182 	cmd &= WD_INTERVAL;
183 	timeout = ((uint64_t)1 << cmd) / ICHWD_TICK;
184 	if (cmd > 0 && cmd <= 63
185 	    && timeout >= ICHWD_MIN_TIMEOUT && timeout <= ICHWD_MAX_TIMEOUT) {
186 		if (timeout != sc->timeout) {
187 			if (!sc->active)
188 				ichwd_tmr_enable(sc);
189 			ichwd_tmr_set(sc, timeout);
190 		}
191 
192 		ichwd_tmr_reload(sc);
193 		*error = 0;
194 	} else {
195 		if (sc->active)
196 			ichwd_tmr_disable(sc);
197 		if (cmd > 0)
198 			*error = EINVAL;
199 	}
200 }
201 
202 static unsigned int pmbase = 0;
203 
204 /*
205  * Look for an ICH LPC interface bridge.  If one is found, register an
206  * ichwd device.  There can be only one.
207  */
208 static void
209 ichwd_identify(driver_t *driver, device_t parent)
210 {
211 	struct ichwd_device *id;
212 	device_t ich = NULL;
213 	device_t dev;
214 
215 	/* look for an ICH LPC interface bridge */
216 	for (id = ichwd_devices; id->desc != NULL; ++id)
217 		if ((ich = pci_find_device(id->vendor, id->device)) != NULL)
218 			break;
219 	if (ich == NULL)
220 		return;
221 
222 	if (bootverbose)
223 		printf("%s(): found ICH chipset: %s\n", __func__, id->desc);
224 
225 	/* get for ACPI base address */
226 	pmbase = pci_read_config(ich, ICH_PMBASE, 2) & ICH_PMBASE_MASK;
227 	if (pmbase == 0) {
228 		if (bootverbose)
229 			printf("%s(): ICH PMBASE register is empty\n",
230 			    __func__);
231 		return;
232 	}
233 
234 	/* try to clear the NO_REBOOT bit */
235 	pci_write_config(ich, ICH_GEN_STA, 0x00, 1);
236 	if (pci_read_config(ich, ICH_GEN_STA, 1) & ICH_GEN_STA_NO_REBOOT) {
237 		if (bootverbose)
238 			printf("%s(): ICH WDT present but disabled\n",
239 			    __func__);
240 		return;
241 	}
242 
243 	/* good, add child to bus */
244 	if ((dev = device_find_child(parent, driver->name, 0)) == NULL)
245 		dev = BUS_ADD_CHILD(parent, 0, driver->name, 0);
246 
247 	if (dev != NULL)
248 		device_set_desc_copy(dev, id->desc);
249 }
250 
251 static int
252 ichwd_probe(device_t dev)
253 {
254 	(void)dev;
255 	return (0);
256 }
257 
258 static int
259 ichwd_attach(device_t dev)
260 {
261 	struct ichwd_softc *sc;
262 
263 	sc = device_get_softc(dev);
264 	sc->device = dev;
265 
266 	if (pmbase == 0) {
267 		printf("Not found\n");
268 	}
269 
270 	/* allocate I/O register space */
271 	sc->smi_rid = 0;
272 	sc->smi_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->smi_rid,
273 	    pmbase + SMI_BASE, ~0ul, SMI_LEN,
274 	    RF_ACTIVE | RF_SHAREABLE);
275 	if (sc->smi_res == NULL) {
276 		device_printf(dev, "unable to reserve SMI registers\n");
277 		goto fail;
278 	}
279 	sc->smi_bst = rman_get_bustag(sc->smi_res);
280 	sc->smi_bsh = rman_get_bushandle(sc->smi_res);
281 
282 	sc->tco_rid = 1;
283 	sc->tco_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->tco_rid,
284 	    pmbase + TCO_BASE, ~0ul, TCO_LEN,
285 	    RF_ACTIVE | RF_SHAREABLE);
286 	if (sc->tco_res == NULL) {
287 		device_printf(dev, "unable to reserve TCO registers\n");
288 		goto fail;
289 	}
290 	sc->tco_bst = rman_get_bustag(sc->tco_res);
291 	sc->tco_bsh = rman_get_bushandle(sc->tco_res);
292 	/* reset the watchdog status registers */
293 
294 	ichwd_sts_reset(sc);
295 
296 	/* make sure the WDT starts out inactive */
297 	ichwd_tmr_disable(sc);
298 
299 	/* register the watchdog event handler */
300 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0);
301 
302 	/* enable watchdog timeout interrupts */
303 	ichwd_intr_enable(sc);
304 
305 	return (0);
306  fail:
307 	sc = device_get_softc(dev);
308 	if (sc->tco_res != NULL)
309 		bus_release_resource(dev, SYS_RES_IOPORT,
310 		    sc->tco_rid, sc->tco_res);
311 	if (sc->smi_res != NULL)
312 		bus_release_resource(dev, SYS_RES_IOPORT,
313 		    sc->smi_rid, sc->smi_res);
314 	return (ENXIO);
315 }
316 
317 static int
318 ichwd_detach(device_t dev)
319 {
320 	struct ichwd_softc *sc;
321 
322 	sc = device_get_softc(dev);
323 
324 	/* halt the watchdog timer */
325 	if (sc->active)
326 		ichwd_tmr_disable(sc);
327 
328 	/* disable watchdog timeout interrupts */
329 	ichwd_intr_disable(sc);
330 
331 	/* deregister event handler */
332 	if (sc->ev_tag != NULL)
333 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
334 	sc->ev_tag = NULL;
335 
336 	/* reset the watchdog status registers */
337 	ichwd_sts_reset(sc);
338 
339 	/* deallocate I/O register space */
340 	bus_release_resource(dev, SYS_RES_IOPORT, sc->tco_rid, sc->tco_res);
341 	bus_release_resource(dev, SYS_RES_IOPORT, sc->smi_rid, sc->smi_res);
342 
343 	return (0);
344 }
345 
346 static device_method_t ichwd_methods[] = {
347 	DEVMETHOD(device_identify, ichwd_identify),
348 	DEVMETHOD(device_probe,	ichwd_probe),
349 	DEVMETHOD(device_attach, ichwd_attach),
350 	DEVMETHOD(device_detach, ichwd_detach),
351 	DEVMETHOD(device_shutdown, ichwd_detach),
352 	{0,0}
353 };
354 
355 static driver_t ichwd_driver = {
356 	"ichwd",
357 	ichwd_methods,
358 	sizeof(struct ichwd_softc),
359 };
360 
361 static int
362 ichwd_modevent(module_t mode, int type, void *data)
363 {
364 	int error = 0;
365 
366 	switch (type) {
367 	case MOD_LOAD:
368 		printf("ichwd module loaded\n");
369 		break;
370 	case MOD_UNLOAD:
371 		printf("ichwd module unloaded\n");
372 		break;
373 	case MOD_SHUTDOWN:
374 		printf("ichwd module shutting down\n");
375 		break;
376 	}
377 	return (error);
378 }
379 
380 DRIVER_MODULE(ichwd, isa, ichwd_driver, ichwd_devclass, ichwd_modevent, NULL);
381