xref: /netbsd-src/sys/arch/x86/pci/tco.c (revision 7d62b00eb9ad855ffcd7da46b41e23feb5476fac)
1 /*	$NetBSD: tco.c,v 1.9 2022/09/22 14:43:04 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2015 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Minoura Makoto and Matthew R. Green.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Intel I/O Controller Hub (ICHn) watchdog timer
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: tco.c,v 1.9 2022/09/22 14:43:04 riastradh Exp $");
38 
39 #include <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/device.h>
43 #include <sys/timetc.h>
44 #include <sys/module.h>
45 
46 #include <dev/pci/pcivar.h>
47 #include <dev/pci/pcireg.h>
48 #include <dev/ic/i82801lpcreg.h>
49 
50 #include <dev/sysmon/sysmonvar.h>
51 
52 #include <arch/x86/pci/tco.h>
53 
54 #include "pcibvar.h"
55 
56 struct tco_softc {
57 	struct sysmon_wdog	sc_smw;
58 	bus_space_tag_t		sc_pmt;
59 	bus_space_handle_t	sc_pmh;
60 	bus_space_tag_t		sc_rcbat;
61 	bus_space_handle_t	sc_rcbah;
62 	struct pcib_softc *	sc_pcib;
63 	bus_space_tag_t		sc_tcot;
64 	bus_space_handle_t	sc_tcoh;
65 	int			sc_armed;
66 	unsigned int		sc_min_t;
67 	unsigned int		sc_max_t;
68 	int			sc_version;
69 	bool			sc_attached;
70 };
71 
72 static int tco_match(device_t, cfdata_t, void *);
73 static void tco_attach(device_t, device_t, void *);
74 static int tco_detach(device_t, int);
75 
76 static bool tco_suspend(device_t, const pmf_qual_t *);
77 
78 static int tcotimer_setmode(struct sysmon_wdog *);
79 static int tcotimer_tickle(struct sysmon_wdog *);
80 static void tcotimer_stop(struct tco_softc *);
81 static void tcotimer_start(struct tco_softc *);
82 static void tcotimer_status_reset(struct tco_softc *);
83 static int  tcotimer_disable_noreboot(device_t);
84 
85 CFATTACH_DECL3_NEW(tco, sizeof(struct tco_softc),
86     tco_match, tco_attach, tco_detach, NULL, NULL, NULL, 0);
87 
88 /*
89  * Autoconf callbacks.
90  */
91 static int
92 tco_match(device_t parent, cfdata_t match, void *aux)
93 {
94 	struct tco_attach_args *ta = aux;
95 
96 	if (ta->ta_pmt == 0)
97 		return 0;
98 
99 	switch (ta->ta_version) {
100 	case TCO_VERSION_RCBA:
101 	case TCO_VERSION_PCIB:
102 		break;
103 	default:
104 		return 0;
105 	}
106 
107 	return 1;
108 }
109 
110 static void
111 tco_attach(device_t parent, device_t self, void *aux)
112 {
113 	struct tco_softc *sc = device_private(self);
114 	struct tco_attach_args *ta = aux;
115 	uint32_t ioreg;
116 
117 	/* Retrieve bus info shared with parent/siblings */
118 	sc->sc_version = ta->ta_version;
119 	sc->sc_pmt = ta->ta_pmt;
120 	sc->sc_pmh = ta->ta_pmh;
121 	sc->sc_rcbat = ta->ta_rcbat;
122 	sc->sc_rcbah = ta->ta_rcbah;
123 	sc->sc_pcib = ta->ta_pcib;
124 
125 	aprint_normal(": TCO (watchdog) timer configured.\n");
126 	aprint_naive("\n");
127 
128 	sc->sc_tcot = sc->sc_pmt;
129 	if (bus_space_subregion(sc->sc_pmt, sc->sc_pmh, PMC_TCO_BASE,
130 		TCO_REGSIZE, &sc->sc_tcoh)) {
131 		aprint_error_dev(self, "failed to map TCO registers\n");
132 		return;
133 	}
134 
135 	/* Explicitly stop the TCO timer. */
136 	tcotimer_stop(sc);
137 
138 	/*
139 	 * Enable TCO timeout SMI only if the hardware reset does not
140 	 * work. We don't know what the SMBIOS does.
141 	 */
142 	ioreg = bus_space_read_4(sc->sc_pmt, sc->sc_pmh, PMC_SMI_EN);
143 	ioreg &= ~PMC_SMI_EN_TCO_EN;
144 
145 	/*
146 	 * Clear the No Reboot (NR) bit. If this fails, enabling the TCO_EN bit
147 	 * in the SMI_EN register is the last chance.
148 	 */
149 	if (tcotimer_disable_noreboot(self)) {
150 		ioreg |= PMC_SMI_EN_TCO_EN;
151 	}
152 	if ((ioreg & PMC_SMI_EN_GBL_SMI_EN) != 0) {
153 		bus_space_write_4(sc->sc_pmt, sc->sc_pmh, PMC_SMI_EN, ioreg);
154 	}
155 
156 	/* Reset the watchdog status registers. */
157 	tcotimer_status_reset(sc);
158 
159 	/*
160 	 * Register the driver with the sysmon watchdog framework.
161 	 */
162 	sc->sc_smw.smw_name = device_xname(self);
163 	sc->sc_smw.smw_cookie = sc;
164 	sc->sc_smw.smw_setmode = tcotimer_setmode;
165 	sc->sc_smw.smw_tickle = tcotimer_tickle;
166 
167 	/*
168 	 * ICH6 or newer are limited to 2ticks min and 613ticks max.
169 	 *                              1sec           367secs
170 	 *
171 	 * ICH5 or older are limited to 4ticks min and 39ticks max.
172 	 *                              2secs          23secs
173 	 */
174 	switch (sc->sc_version) {
175 	case TCO_VERSION_RCBA:
176 		sc->sc_max_t = TCOTIMER2_MAX_TICK;
177 		sc->sc_min_t = TCOTIMER2_MIN_TICK;
178 		break;
179 	case TCO_VERSION_PCIB:
180 		sc->sc_max_t = TCOTIMER_MAX_TICK;
181 		sc->sc_min_t = TCOTIMER_MIN_TICK;
182 		break;
183 	}
184 	sc->sc_smw.smw_period = tcotimer_tick_to_second(sc->sc_max_t);
185 
186 	aprint_verbose_dev(self, "Min/Max interval %u/%u seconds\n",
187 		tcotimer_tick_to_second(sc->sc_min_t),
188 		tcotimer_tick_to_second(sc->sc_max_t));
189 
190 	if (sysmon_wdog_register(&sc->sc_smw))
191 		aprint_error_dev(self, "unable to register TCO timer"
192 		       "as a sysmon watchdog device.\n");
193 
194 	if (!pmf_device_register(self, tco_suspend, NULL))
195 		aprint_error_dev(self, "unable to register with pmf\n");
196 
197 	sc->sc_attached = true;
198 }
199 
200 static int
201 tco_detach(device_t self, int flags)
202 {
203 	struct tco_softc *sc = device_private(self);
204 	int rc;
205 
206 	if (!sc->sc_attached)
207 		return 0;
208 
209 	if ((rc = sysmon_wdog_unregister(&sc->sc_smw)) != 0) {
210 		if (rc == ERESTART)
211 			rc = EINTR;
212 		return rc;
213 	}
214 
215 	/* Explicitly stop the TCO timer. */
216 	tcotimer_stop(sc);
217 
218 	/* XXX Set No Reboot? */
219 
220 	pmf_device_deregister(self);
221 
222 	return 0;
223 }
224 
225 static bool
226 tco_suspend(device_t self, const pmf_qual_t *quals)
227 {
228 	struct tco_softc *sc = device_private(self);
229 
230 	/* Allow suspend only if watchdog is not armed */
231 
232 	return ((sc->sc_smw.smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED);
233 }
234 
235 /*
236  * Sysmon watchdog callbacks.
237  */
238 static int
239 tcotimer_setmode(struct sysmon_wdog *smw)
240 {
241 	struct tco_softc *sc = smw->smw_cookie;
242 	unsigned int period;
243 	uint16_t ich6period = 0;
244 	uint8_t ich5period = 0;
245 
246 	if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
247 		/* Stop the TCO timer. */
248 		tcotimer_stop(sc);
249 	} else {
250 		period = tcotimer_second_to_tick(smw->smw_period);
251 		if (period < sc->sc_min_t || period > sc->sc_max_t)
252 			return EINVAL;
253 
254 		/* Stop the TCO timer, */
255 		tcotimer_stop(sc);
256 
257 		/* set the timeout, */
258 		switch (sc->sc_version) {
259 		case TCO_VERSION_RCBA:
260 			/* ICH6 or newer */
261 			ich6period = bus_space_read_2(sc->sc_tcot, sc->sc_tcoh,
262 			    TCO_TMR2);
263 			ich6period &= 0xfc00;
264 			bus_space_write_2(sc->sc_tcot, sc->sc_tcoh,
265 			    TCO_TMR2, ich6period | period);
266 			break;
267 		case TCO_VERSION_PCIB:
268 			/* ICH5 or older */
269 			ich5period = bus_space_read_1(sc->sc_tcot, sc->sc_tcoh,
270 			    TCO_TMR);
271 			ich5period &= 0xc0;
272 			bus_space_write_1(sc->sc_tcot, sc->sc_tcoh,
273 			    TCO_TMR, ich5period | period);
274 			break;
275 		}
276 
277 		/* and start/reload the timer. */
278 		tcotimer_start(sc);
279 		tcotimer_tickle(smw);
280 	}
281 
282 	return 0;
283 }
284 
285 static int
286 tcotimer_tickle(struct sysmon_wdog *smw)
287 {
288 	struct tco_softc *sc = smw->smw_cookie;
289 
290 	/* any value is allowed */
291 	switch (sc->sc_version) {
292 	case TCO_VERSION_RCBA:
293 		bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO_RLD, 1);
294 		break;
295 	case TCO_VERSION_PCIB:
296 		bus_space_write_1(sc->sc_tcot, sc->sc_tcoh, TCO_RLD, 1);
297 		break;
298 	}
299 
300 	return 0;
301 }
302 
303 static void
304 tcotimer_stop(struct tco_softc *sc)
305 {
306 	uint16_t ioreg;
307 
308 	ioreg = bus_space_read_2(sc->sc_tcot, sc->sc_tcoh, TCO1_CNT);
309 	ioreg |= TCO1_CNT_TCO_TMR_HLT;
310 	bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO1_CNT, ioreg);
311 }
312 
313 static void
314 tcotimer_start(struct tco_softc *sc)
315 {
316 	uint16_t ioreg;
317 
318 	ioreg = bus_space_read_2(sc->sc_tcot, sc->sc_tcoh, TCO1_CNT);
319 	ioreg &= ~TCO1_CNT_TCO_TMR_HLT;
320 	bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO1_CNT, ioreg);
321 }
322 
323 static void
324 tcotimer_status_reset(struct tco_softc *sc)
325 {
326 	bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO1_STS,
327 	    TCO1_STS_TIMEOUT);
328 	bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO2_STS,
329 	    TCO2_STS_BOOT_STS);
330 	bus_space_write_2(sc->sc_tcot, sc->sc_tcoh, TCO2_STS,
331 	    TCO2_STS_SECONDS_TO_STS);
332 }
333 
334 /*
335  * Clear the No Reboot (NR) bit, this enables reboots when the timer
336  * reaches the timeout for the second time.
337  */
338 static int
339 tcotimer_disable_noreboot(device_t self)
340 {
341 	struct tco_softc *sc = device_private(self);
342 
343 	switch (sc->sc_version) {
344 	case TCO_VERSION_RCBA: {
345 		uint32_t status;
346 
347 		status = bus_space_read_4(sc->sc_rcbat, sc->sc_rcbah,
348 		    LPCIB_GCS_OFFSET);
349 		status &= ~LPCIB_GCS_NO_REBOOT;
350 		bus_space_write_4(sc->sc_rcbat, sc->sc_rcbah,
351 		    LPCIB_GCS_OFFSET, status);
352 		status = bus_space_read_4(sc->sc_rcbat, sc->sc_rcbah,
353 		    LPCIB_GCS_OFFSET);
354 		if (status & LPCIB_GCS_NO_REBOOT)
355 			goto error;
356 		break;
357 	}
358 	case TCO_VERSION_PCIB: {
359 		pcireg_t pcireg;
360 
361 		pcireg = pci_conf_read(sc->sc_pcib->sc_pc, sc->sc_pcib->sc_tag,
362 		    LPCIB_PCI_GEN_STA);
363 		if (pcireg & LPCIB_PCI_GEN_STA_NO_REBOOT) {
364 			/* TCO timeout reset is disabled; try to enable it */
365 			pcireg &= ~LPCIB_PCI_GEN_STA_NO_REBOOT;
366 			pci_conf_write(sc->sc_pcib->sc_pc, sc->sc_pcib->sc_tag,
367 			    LPCIB_PCI_GEN_STA, pcireg);
368 			if (pcireg & LPCIB_PCI_GEN_STA_NO_REBOOT)
369 				goto error;
370 		}
371 		break;
372 	}
373 	}
374 
375 	return 0;
376 error:
377 	aprint_error_dev(self, "TCO timer reboot disabled by hardware; "
378 	    "hope SMBIOS properly handles it.\n");
379 	return EINVAL;
380 }
381 
382 MODULE(MODULE_CLASS_DRIVER, tco, "sysmon_wdog");
383 
384 #ifdef _MODULE
385 #include "ioconf.c"
386 #endif
387 
388 static int
389 tco_modcmd(modcmd_t cmd, void *arg)
390 {
391 	int ret = 0;
392 
393 	switch (cmd) {
394 	case MODULE_CMD_INIT:
395 #ifdef _MODULE
396 		ret = config_init_component(cfdriver_ioconf_tco,
397 		    cfattach_ioconf_tco,
398 		    cfdata_ioconf_tco);
399 #endif
400 		break;
401 	case MODULE_CMD_FINI:
402 #ifdef _MODULE
403 		ret = config_fini_component(cfdriver_ioconf_tco,
404 		    cfattach_ioconf_tco,
405 		    cfdata_ioconf_tco);
406 #endif
407 		break;
408 	default:
409 		ret = ENOTTY;
410 	}
411 
412 	return ret;
413 }
414