ichwd.c revision 167950 
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: head/sys/dev/ichwd/ichwd.c 167950 2007-03-27 21:03:37Z n_hibma $");
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
73static 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
90static 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
111static __inline void
112ichwd_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
117static __inline void
118ichwd_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
123static __inline void
124ichwd_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
131static __inline void
132ichwd_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
143static __inline void
144ichwd_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
155static __inline void
156ichwd_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
163static __inline void
164ichwd_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 */
175static void
176ichwd_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	}
198}
199
200static unsigned int pmbase = 0;
201
202/*
203 * Look for an ICH LPC interface bridge.  If one is found, register an
204 * ichwd device.  There can be only one.
205 */
206static void
207ichwd_identify(driver_t *driver, device_t parent)
208{
209	struct ichwd_device *id;
210	device_t ich = NULL;
211	device_t dev;
212
213	/* look for an ICH LPC interface bridge */
214	for (id = ichwd_devices; id->desc != NULL; ++id)
215		if ((ich = pci_find_device(id->vendor, id->device)) != NULL)
216			break;
217	if (ich == NULL)
218		return;
219
220	if (bootverbose)
221		printf("%s(): found ICH chipset: %s\n", __func__, id->desc);
222
223	/* get for ACPI base address */
224	pmbase = pci_read_config(ich, ICH_PMBASE, 2) & ICH_PMBASE_MASK;
225	if (pmbase == 0) {
226		if (bootverbose)
227			printf("%s(): ICH PMBASE register is empty\n",
228			    __func__);
229		return;
230	}
231
232	/* try to clear the NO_REBOOT bit */
233	pci_write_config(ich, ICH_GEN_STA, 0x00, 1);
234	if (pci_read_config(ich, ICH_GEN_STA, 1) & ICH_GEN_STA_NO_REBOOT) {
235		if (bootverbose)
236			printf("%s(): ICH WDT present but disabled\n",
237			    __func__);
238		return;
239	}
240
241	/* good, add child to bus */
242	if ((dev = device_find_child(parent, driver->name, 0)) == NULL)
243		dev = BUS_ADD_CHILD(parent, 0, driver->name, 0);
244
245	if (dev != NULL)
246		device_set_desc_copy(dev, id->desc);
247}
248
249static int
250ichwd_probe(device_t dev)
251{
252	(void)dev;
253	return (0);
254}
255
256static int
257ichwd_attach(device_t dev)
258{
259	struct ichwd_softc *sc;
260
261	sc = device_get_softc(dev);
262	sc->device = dev;
263
264	if (pmbase == 0) {
265		printf("Not found\n");
266	}
267
268	/* allocate I/O register space */
269	sc->smi_rid = 0;
270	sc->smi_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->smi_rid,
271	    pmbase + SMI_BASE, ~0ul, SMI_LEN,
272	    RF_ACTIVE | RF_SHAREABLE);
273	if (sc->smi_res == NULL) {
274		device_printf(dev, "unable to reserve SMI registers\n");
275		goto fail;
276	}
277	sc->smi_bst = rman_get_bustag(sc->smi_res);
278	sc->smi_bsh = rman_get_bushandle(sc->smi_res);
279
280	sc->tco_rid = 1;
281	sc->tco_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->tco_rid,
282	    pmbase + TCO_BASE, ~0ul, TCO_LEN,
283	    RF_ACTIVE | RF_SHAREABLE);
284	if (sc->tco_res == NULL) {
285		device_printf(dev, "unable to reserve TCO registers\n");
286		goto fail;
287	}
288	sc->tco_bst = rman_get_bustag(sc->tco_res);
289	sc->tco_bsh = rman_get_bushandle(sc->tco_res);
290	/* reset the watchdog status registers */
291
292	ichwd_sts_reset(sc);
293
294	/* make sure the WDT starts out inactive */
295	ichwd_tmr_disable(sc);
296
297	/* register the watchdog event handler */
298	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, ichwd_event, sc, 0);
299
300	/* enable watchdog timeout interrupts */
301	ichwd_intr_enable(sc);
302
303	return (0);
304 fail:
305	sc = device_get_softc(dev);
306	if (sc->tco_res != NULL)
307		bus_release_resource(dev, SYS_RES_IOPORT,
308		    sc->tco_rid, sc->tco_res);
309	if (sc->smi_res != NULL)
310		bus_release_resource(dev, SYS_RES_IOPORT,
311		    sc->smi_rid, sc->smi_res);
312	return (ENXIO);
313}
314
315static int
316ichwd_detach(device_t dev)
317{
318	struct ichwd_softc *sc;
319
320	sc = device_get_softc(dev);
321
322	/* halt the watchdog timer */
323	if (sc->active)
324		ichwd_tmr_disable(sc);
325
326	/* disable watchdog timeout interrupts */
327	ichwd_intr_disable(sc);
328
329	/* deregister event handler */
330	if (sc->ev_tag != NULL)
331		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
332	sc->ev_tag = NULL;
333
334	/* reset the watchdog status registers */
335	ichwd_sts_reset(sc);
336
337	/* deallocate I/O register space */
338	bus_release_resource(dev, SYS_RES_IOPORT, sc->tco_rid, sc->tco_res);
339	bus_release_resource(dev, SYS_RES_IOPORT, sc->smi_rid, sc->smi_res);
340
341	return (0);
342}
343
344static device_method_t ichwd_methods[] = {
345	DEVMETHOD(device_identify, ichwd_identify),
346	DEVMETHOD(device_probe,	ichwd_probe),
347	DEVMETHOD(device_attach, ichwd_attach),
348	DEVMETHOD(device_detach, ichwd_detach),
349	DEVMETHOD(device_shutdown, ichwd_detach),
350	{0,0}
351};
352
353static driver_t ichwd_driver = {
354	"ichwd",
355	ichwd_methods,
356	sizeof(struct ichwd_softc),
357};
358
359static int
360ichwd_modevent(module_t mode, int type, void *data)
361{
362	int error = 0;
363
364	switch (type) {
365	case MOD_LOAD:
366		printf("ichwd module loaded\n");
367		break;
368	case MOD_UNLOAD:
369		printf("ichwd module unloaded\n");
370		break;
371	case MOD_SHUTDOWN:
372		printf("ichwd module shutting down\n");
373		break;
374	}
375	return (error);
376}
377
378DRIVER_MODULE(ichwd, isa, ichwd_driver, ichwd_devclass, ichwd_modevent, NULL);
379