xref: /freebsd/sys/dev/amdsbwd/amdsbwd.c (revision 39ee7a7a6bdd1557b1c3532abf60d139798ac88b)
1 /*-
2  * Copyright (c) 2009 Andriy Gapon <avg@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * This is a driver for watchdog timer present in AMD SB600/SB7xx/SB8xx
29  * southbridges.
30  * Please see the following specifications for the descriptions of the
31  * registers and flags:
32  * - AMD SB600 Register Reference Guide, Public Version,  Rev. 3.03 (SB600 RRG)
33  *   http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/46155_sb600_rrg_pub_3.03.pdf
34  * - AMD SB700/710/750 Register Reference Guide (RRG)
35  *   http://developer.amd.com/assets/43009_sb7xx_rrg_pub_1.00.pdf
36  * - AMD SB700/710/750 Register Programming Requirements (RPR)
37  *   http://developer.amd.com/assets/42413_sb7xx_rpr_pub_1.00.pdf
38  * - AMD SB800-Series Southbridges Register Reference Guide (RRG)
39  *   http://support.amd.com/us/Embedded_TechDocs/45482.pdf
40  * Please see the following for Watchdog Resource Table specification:
41  * - Watchdog Timer Hardware Requirements for Windows Server 2003 (WDRT)
42  *   http://www.microsoft.com/whdc/system/sysinternals/watchdog.mspx
43  * AMD SB600/SB7xx/SB8xx watchdog hardware seems to conform to the above
44  * specifications, but the table hasn't been spotted in the wild yet.
45  */
46 
47 #include <sys/cdefs.h>
48 __FBSDID("$FreeBSD$");
49 
50 #include <sys/param.h>
51 #include <sys/kernel.h>
52 #include <sys/module.h>
53 #include <sys/systm.h>
54 #include <sys/sysctl.h>
55 #include <sys/bus.h>
56 #include <machine/bus.h>
57 #include <sys/rman.h>
58 #include <machine/resource.h>
59 #include <sys/watchdog.h>
60 
61 #include <dev/pci/pcivar.h>
62 #include <isa/isavar.h>
63 
64 /* SB7xx RRG 2.3.3.1.1. */
65 #define	AMDSB_PMIO_INDEX		0xcd6
66 #define	AMDSB_PMIO_DATA			(PMIO_INDEX + 1)
67 #define	AMDSB_PMIO_WIDTH		2
68 /* SB7xx RRG 2.3.3.2. */
69 #define	AMDSB_PM_RESET_STATUS0		0x44
70 #define	AMDSB_PM_RESET_STATUS1		0x45
71 #define		AMDSB_WD_RST_STS	0x02
72 /* SB7xx RRG 2.3.3.2, RPR 2.36. */
73 #define	AMDSB_PM_WDT_CTRL		0x69
74 #define		AMDSB_WDT_DISABLE	0x01
75 #define		AMDSB_WDT_RES_MASK	(0x02 | 0x04)
76 #define		AMDSB_WDT_RES_32US	0x00
77 #define		AMDSB_WDT_RES_10MS	0x02
78 #define		AMDSB_WDT_RES_100MS	0x04
79 #define		AMDSB_WDT_RES_1S	0x06
80 #define	AMDSB_PM_WDT_BASE_LSB		0x6c
81 #define	AMDSB_PM_WDT_BASE_MSB		0x6f
82 /* SB8xx RRG 2.3.3. */
83 #define	AMDSB8_PM_WDT_EN		0x48
84 #define		AMDSB8_WDT_DEC_EN	0x01
85 #define		AMDSB8_WDT_DISABLE	0x02
86 #define	AMDSB8_PM_WDT_CTRL		0x4c
87 #define		AMDSB8_WDT_32KHZ	0x00
88 #define		AMDSB8_WDT_1HZ		0x03
89 #define		AMDSB8_WDT_RES_MASK	0x03
90 #define	AMDSB8_PM_RESET_STATUS0		0xC0
91 #define	AMDSB8_PM_RESET_STATUS1		0xC1
92 #define		AMDSB8_WD_RST_STS	0x20
93 /* SB7xx RRG 2.3.4, WDRT. */
94 #define	AMDSB_WD_CTRL			0x00
95 #define		AMDSB_WD_RUN		0x01
96 #define		AMDSB_WD_FIRED		0x02
97 #define		AMDSB_WD_SHUTDOWN	0x04
98 #define		AMDSB_WD_DISABLE	0x08
99 #define		AMDSB_WD_RESERVED	0x70
100 #define		AMDSB_WD_RELOAD		0x80
101 #define	AMDSB_WD_COUNT			0x04
102 #define		AMDSB_WD_COUNT_MASK	0xffff
103 #define	AMDSB_WDIO_REG_WIDTH		4
104 /* WDRT */
105 #define	MAXCOUNT_MIN_VALUE		511
106 /* SB7xx RRG 2.3.1.1, SB600 RRG 2.3.1.1, SB8xx RRG 2.3.1.  */
107 #define	AMDSB_SMBUS_DEVID		0x43851002
108 #define	AMDSB8_SMBUS_REVID		0x40
109 
110 #define	amdsbwd_verbose_printf(dev, ...)	\
111 	do {						\
112 		if (bootverbose)			\
113 			device_printf(dev, __VA_ARGS__);\
114 	} while (0)
115 
116 struct amdsbwd_softc {
117 	device_t		dev;
118 	eventhandler_tag	ev_tag;
119 	struct resource		*res_ctrl;
120 	struct resource		*res_count;
121 	int			rid_ctrl;
122 	int			rid_count;
123 	int			ms_per_tick;
124 	int			max_ticks;
125 	int			active;
126 	unsigned int		timeout;
127 };
128 
129 static void	amdsbwd_identify(driver_t *driver, device_t parent);
130 static int	amdsbwd_probe(device_t dev);
131 static int	amdsbwd_attach(device_t dev);
132 static int	amdsbwd_detach(device_t dev);
133 
134 static device_method_t amdsbwd_methods[] = {
135 	DEVMETHOD(device_identify,	amdsbwd_identify),
136 	DEVMETHOD(device_probe,		amdsbwd_probe),
137 	DEVMETHOD(device_attach,	amdsbwd_attach),
138 	DEVMETHOD(device_detach,	amdsbwd_detach),
139 #if 0
140 	DEVMETHOD(device_shutdown,	amdsbwd_detach),
141 #endif
142 	DEVMETHOD_END
143 };
144 
145 static devclass_t	amdsbwd_devclass;
146 static driver_t		amdsbwd_driver = {
147 	"amdsbwd",
148 	amdsbwd_methods,
149 	sizeof(struct amdsbwd_softc)
150 };
151 
152 DRIVER_MODULE(amdsbwd, isa, amdsbwd_driver, amdsbwd_devclass, NULL, NULL);
153 
154 
155 static uint8_t
156 pmio_read(struct resource *res, uint8_t reg)
157 {
158 	bus_write_1(res, 0, reg);	/* Index */
159 	return (bus_read_1(res, 1));	/* Data */
160 }
161 
162 static void
163 pmio_write(struct resource *res, uint8_t reg, uint8_t val)
164 {
165 	bus_write_1(res, 0, reg);	/* Index */
166 	bus_write_1(res, 1, val);	/* Data */
167 }
168 
169 static uint32_t
170 wdctrl_read(struct amdsbwd_softc *sc)
171 {
172 	return (bus_read_4(sc->res_ctrl, 0));
173 }
174 
175 static void
176 wdctrl_write(struct amdsbwd_softc *sc, uint32_t val)
177 {
178 	bus_write_4(sc->res_ctrl, 0, val);
179 }
180 
181 static __unused uint32_t
182 wdcount_read(struct amdsbwd_softc *sc)
183 {
184 	return (bus_read_4(sc->res_count, 0));
185 }
186 
187 static void
188 wdcount_write(struct amdsbwd_softc *sc, uint32_t val)
189 {
190 	bus_write_4(sc->res_count, 0, val);
191 }
192 
193 static void
194 amdsbwd_tmr_enable(struct amdsbwd_softc *sc)
195 {
196 	uint32_t val;
197 
198 	val = wdctrl_read(sc);
199 	val |= AMDSB_WD_RUN;
200 	wdctrl_write(sc, val);
201 	sc->active = 1;
202 	amdsbwd_verbose_printf(sc->dev, "timer enabled\n");
203 }
204 
205 static void
206 amdsbwd_tmr_disable(struct amdsbwd_softc *sc)
207 {
208 	uint32_t val;
209 
210 	val = wdctrl_read(sc);
211 	val &= ~AMDSB_WD_RUN;
212 	wdctrl_write(sc, val);
213 	sc->active = 0;
214 	amdsbwd_verbose_printf(sc->dev, "timer disabled\n");
215 }
216 
217 static void
218 amdsbwd_tmr_reload(struct amdsbwd_softc *sc)
219 {
220 	uint32_t val;
221 
222 	val = wdctrl_read(sc);
223 	val |= AMDSB_WD_RELOAD;
224 	wdctrl_write(sc, val);
225 }
226 
227 static void
228 amdsbwd_tmr_set(struct amdsbwd_softc *sc, uint16_t timeout)
229 {
230 
231 	timeout &= AMDSB_WD_COUNT_MASK;
232 	wdcount_write(sc, timeout);
233 	sc->timeout = timeout;
234 	amdsbwd_verbose_printf(sc->dev, "timeout set to %u ticks\n", timeout);
235 }
236 
237 static void
238 amdsbwd_event(void *arg, unsigned int cmd, int *error)
239 {
240 	struct amdsbwd_softc *sc = arg;
241 	unsigned int timeout;
242 
243 	/* convert from power-of-two-ns to WDT ticks */
244 	cmd &= WD_INTERVAL;
245 	if (cmd < WD_TO_1SEC)
246 		cmd = 0;
247 	if (cmd) {
248 		timeout = ((uint64_t)1 << (cmd - WD_TO_1MS)) / sc->ms_per_tick;
249 		if (timeout > sc->max_ticks)
250 			timeout = sc->max_ticks;
251 		if (timeout != sc->timeout) {
252 			amdsbwd_tmr_set(sc, timeout);
253 			if (!sc->active)
254 				amdsbwd_tmr_enable(sc);
255 		}
256 		amdsbwd_tmr_reload(sc);
257 		*error = 0;
258 	} else {
259 		if (sc->active)
260 			amdsbwd_tmr_disable(sc);
261 	}
262 }
263 
264 static void
265 amdsbwd_identify(driver_t *driver, device_t parent)
266 {
267 	device_t		child;
268 	device_t		smb_dev;
269 
270 	if (resource_disabled("amdsbwd", 0))
271 		return;
272 	if (device_find_child(parent, "amdsbwd", -1) != NULL)
273 		return;
274 
275 	/*
276 	 * Try to identify SB600/SB7xx by PCI Device ID of SMBus device
277 	 * that should be present at bus 0, device 20, function 0.
278 	 */
279 	smb_dev = pci_find_bsf(0, 20, 0);
280 	if (smb_dev == NULL)
281 		return;
282 	if (pci_get_devid(smb_dev) != AMDSB_SMBUS_DEVID)
283 		return;
284 
285 	child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "amdsbwd", -1);
286 	if (child == NULL)
287 		device_printf(parent, "add amdsbwd child failed\n");
288 }
289 
290 
291 static void
292 amdsbwd_probe_sb7xx(device_t dev, struct resource *pmres, uint32_t *addr)
293 {
294 	uint32_t	val;
295 	int		i;
296 
297 	/* Report cause of previous reset for user's convenience. */
298 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS0);
299 	if (val != 0)
300 		amdsbwd_verbose_printf(dev, "ResetStatus0 = %#04x\n", val);
301 	val = pmio_read(pmres, AMDSB_PM_RESET_STATUS1);
302 	if (val != 0)
303 		amdsbwd_verbose_printf(dev, "ResetStatus1 = %#04x\n", val);
304 	if ((val & AMDSB_WD_RST_STS) != 0)
305 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
306 
307 	/* Find base address of memory mapped WDT registers. */
308 	for (*addr = 0, i = 0; i < 4; i++) {
309 		*addr <<= 8;
310 		*addr |= pmio_read(pmres, AMDSB_PM_WDT_BASE_MSB - i);
311 	}
312 	/* Set watchdog timer tick to 1s. */
313 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
314 	val &= ~AMDSB_WDT_RES_MASK;
315 	val |= AMDSB_WDT_RES_10MS;
316 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
317 
318 	/* Enable watchdog device (in stopped state). */
319 	val = pmio_read(pmres, AMDSB_PM_WDT_CTRL);
320 	val &= ~AMDSB_WDT_DISABLE;
321 	pmio_write(pmres, AMDSB_PM_WDT_CTRL, val);
322 
323 	/*
324 	 * XXX TODO: Ensure that watchdog decode is enabled
325 	 * (register 0x41, bit 3).
326 	 */
327 	device_set_desc(dev, "AMD SB600/SB7xx Watchdog Timer");
328 }
329 
330 static void
331 amdsbwd_probe_sb8xx(device_t dev, struct resource *pmres, uint32_t *addr)
332 {
333 	uint32_t	val;
334 	int		i;
335 
336 	/* Report cause of previous reset for user's convenience. */
337 	val = pmio_read(pmres, AMDSB8_PM_RESET_STATUS0);
338 	if (val != 0)
339 		amdsbwd_verbose_printf(dev, "ResetStatus0 = %#04x\n", val);
340 	val = pmio_read(pmres, AMDSB8_PM_RESET_STATUS1);
341 	if (val != 0)
342 		amdsbwd_verbose_printf(dev, "ResetStatus1 = %#04x\n", val);
343 	if ((val & AMDSB8_WD_RST_STS) != 0)
344 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
345 
346 	/* Find base address of memory mapped WDT registers. */
347 	for (*addr = 0, i = 0; i < 4; i++) {
348 		*addr <<= 8;
349 		*addr |= pmio_read(pmres, AMDSB8_PM_WDT_EN + 3 - i);
350 	}
351 	*addr &= ~0x07u;
352 
353 	/* Set watchdog timer tick to 1s. */
354 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
355 	val &= ~AMDSB8_WDT_RES_MASK;
356 	val |= AMDSB8_WDT_1HZ;
357 	pmio_write(pmres, AMDSB8_PM_WDT_CTRL, val);
358 #ifdef AMDSBWD_DEBUG
359 	val = pmio_read(pmres, AMDSB8_PM_WDT_CTRL);
360 	amdsbwd_verbose_printf(dev, "AMDSB8_PM_WDT_CTRL value = %#02x\n", val);
361 #endif
362 
363 	/*
364 	 * Enable watchdog device (in stopped state)
365 	 * and decoding of its address.
366 	 */
367 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
368 	val &= ~AMDSB8_WDT_DISABLE;
369 	val |= AMDSB8_WDT_DEC_EN;
370 	pmio_write(pmres, AMDSB8_PM_WDT_EN, val);
371 #ifdef AMDSBWD_DEBUG
372 	val = pmio_read(pmres, AMDSB8_PM_WDT_EN);
373 	device_printf(dev, "AMDSB8_PM_WDT_EN value = %#02x\n", val);
374 #endif
375 	device_set_desc(dev, "AMD SB8xx Watchdog Timer");
376 }
377 
378 static int
379 amdsbwd_probe(device_t dev)
380 {
381 	struct resource		*res;
382 	device_t		smb_dev;
383 	uint32_t		addr;
384 	int			rid;
385 	int			rc;
386 
387 	/* Do not claim some ISA PnP device by accident. */
388 	if (isa_get_logicalid(dev) != 0)
389 		return (ENXIO);
390 
391 	rc = bus_set_resource(dev, SYS_RES_IOPORT, 0, AMDSB_PMIO_INDEX,
392 	    AMDSB_PMIO_WIDTH);
393 	if (rc != 0) {
394 		device_printf(dev, "bus_set_resource for IO failed\n");
395 		return (ENXIO);
396 	}
397 	rid = 0;
398 	res = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0ul, ~0ul,
399 	    AMDSB_PMIO_WIDTH, RF_ACTIVE | RF_SHAREABLE);
400 	if (res == NULL) {
401 		device_printf(dev, "bus_alloc_resource for IO failed\n");
402 		return (ENXIO);
403 	}
404 
405 	smb_dev = pci_find_bsf(0, 20, 0);
406 	KASSERT(smb_dev != NULL, ("can't find SMBus PCI device\n"));
407 	if (pci_get_revid(smb_dev) < AMDSB8_SMBUS_REVID)
408 		amdsbwd_probe_sb7xx(dev, res, &addr);
409 	else
410 		amdsbwd_probe_sb8xx(dev, res, &addr);
411 
412 	bus_release_resource(dev, SYS_RES_IOPORT, rid, res);
413 	bus_delete_resource(dev, SYS_RES_IOPORT, rid);
414 
415 	amdsbwd_verbose_printf(dev, "memory base address = %#010x\n", addr);
416 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 0, addr + AMDSB_WD_CTRL,
417 	    AMDSB_WDIO_REG_WIDTH);
418 	if (rc != 0) {
419 		device_printf(dev, "bus_set_resource for control failed\n");
420 		return (ENXIO);
421 	}
422 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 1, addr + AMDSB_WD_COUNT,
423 	    AMDSB_WDIO_REG_WIDTH);
424 	if (rc != 0) {
425 		device_printf(dev, "bus_set_resource for count failed\n");
426 		return (ENXIO);
427 	}
428 
429 	return (0);
430 }
431 
432 static int
433 amdsbwd_attach_sb(device_t dev, struct amdsbwd_softc *sc)
434 {
435 	device_t	smb_dev;
436 
437 	sc->max_ticks = UINT16_MAX;
438 	sc->rid_ctrl = 0;
439 	sc->rid_count = 1;
440 
441 	smb_dev = pci_find_bsf(0, 20, 0);
442 	KASSERT(smb_dev != NULL, ("can't find SMBus PCI device\n"));
443 	if (pci_get_revid(smb_dev) < AMDSB8_SMBUS_REVID)
444 		sc->ms_per_tick = 10;
445 	else
446 		sc->ms_per_tick = 1000;
447 
448 	sc->res_ctrl = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
449 	    &sc->rid_ctrl, RF_ACTIVE);
450 	if (sc->res_ctrl == NULL) {
451 		device_printf(dev, "bus_alloc_resource for ctrl failed\n");
452 		return (ENXIO);
453 	}
454 	sc->res_count = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
455 	    &sc->rid_count, RF_ACTIVE);
456 	if (sc->res_count == NULL) {
457 		device_printf(dev, "bus_alloc_resource for count failed\n");
458 		return (ENXIO);
459 	}
460 	return (0);
461 }
462 
463 static int
464 amdsbwd_attach(device_t dev)
465 {
466 	struct amdsbwd_softc	*sc;
467 	int			rc;
468 
469 	sc = device_get_softc(dev);
470 	sc->dev = dev;
471 
472 	rc = amdsbwd_attach_sb(dev, sc);
473 	if (rc != 0)
474 		goto fail;
475 
476 #ifdef AMDSBWD_DEBUG
477 	device_printf(dev, "wd ctrl = %#04x\n", wdctrl_read(sc));
478 	device_printf(dev, "wd count = %#04x\n", wdcount_read(sc));
479 #endif
480 
481 	/* Setup initial state of Watchdog Control. */
482 	wdctrl_write(sc, AMDSB_WD_FIRED);
483 
484 	if (wdctrl_read(sc) & AMDSB_WD_DISABLE) {
485 		device_printf(dev, "watchdog hardware is disabled\n");
486 		goto fail;
487 	}
488 
489 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, amdsbwd_event, sc,
490 	    EVENTHANDLER_PRI_ANY);
491 
492 	return (0);
493 
494 fail:
495 	amdsbwd_detach(dev);
496 	return (ENXIO);
497 }
498 
499 static int
500 amdsbwd_detach(device_t dev)
501 {
502 	struct amdsbwd_softc *sc;
503 
504 	sc = device_get_softc(dev);
505 	if (sc->ev_tag != NULL)
506 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
507 
508 	if (sc->active)
509 		amdsbwd_tmr_disable(sc);
510 
511 	if (sc->res_ctrl != NULL)
512 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_ctrl,
513 		    sc->res_ctrl);
514 
515 	if (sc->res_count != NULL)
516 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_count,
517 		    sc->res_count);
518 
519 	return (0);
520 }
521 
522