xref: /freebsd/sys/dev/amdsbwd/amdsbwd.c (revision aa0a1e58)
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
29  * south bridges and other watchdog timers advertised via WDRT ACPI table.
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  * Please see the following for Watchdog Resource Table specification:
39  * - Watchdog Timer Hardware Requirements for Windows Server 2003 (WDRT)
40  *   http://www.microsoft.com/whdc/system/sysinternals/watchdog.mspx
41  * AMD SB600/SB7xx watchdog hardware seems to conform to the above,
42  * but my system doesn't provide the table.
43  */
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <sys/param.h>
49 #include <sys/kernel.h>
50 #include <sys/module.h>
51 #include <sys/systm.h>
52 #include <sys/sysctl.h>
53 #include <sys/bus.h>
54 #include <machine/bus.h>
55 #include <sys/rman.h>
56 #include <machine/resource.h>
57 #include <sys/watchdog.h>
58 
59 #include <dev/pci/pcivar.h>
60 #include <isa/isavar.h>
61 
62 /* RRG 2.3.3.1.1, page 161. */
63 #define	AMDSB_PMIO_INDEX		0xcd6
64 #define	AMDSB_PMIO_DATA			(PMIO_INDEX + 1)
65 #define	AMDSB_PMIO_WIDTH		2
66 /* RRG 2.3.3.2, page 181. */
67 #define	AMDSB_PM_RESET_STATUS0		0x44
68 #define	AMDSB_PM_RESET_STATUS1		0x45
69 #define		AMDSB_WD_RST_STS	0x02
70 /* RRG 2.3.3.2, page 188; RPR 2.36, page 30. */
71 #define	AMDSB_PM_WDT_CTRL		0x69
72 #define		AMDSB_WDT_DISABLE	0x01
73 #define		AMDSB_WDT_RES_MASK	(0x02 | 0x04)
74 #define		AMDSB_WDT_RES_32US	0x00
75 #define		AMDSB_WDT_RES_10MS	0x02
76 #define		AMDSB_WDT_RES_100MS	0x04
77 #define		AMDSB_WDT_RES_1S	0x06
78 #define	AMDSB_PM_WDT_BASE_LSB		0x6c
79 #define	AMDSB_PM_WDT_BASE_MSB		0x6f
80 /* RRG 2.3.4, page 223, WDRT. */
81 #define	AMDSB_WD_CTRL			0x00
82 #define		AMDSB_WD_RUN		0x01
83 #define		AMDSB_WD_FIRED		0x02
84 #define		AMDSB_WD_SHUTDOWN	0x04
85 #define		AMDSB_WD_DISABLE	0x08
86 #define		AMDSB_WD_RESERVED	0x70
87 #define		AMDSB_WD_RELOAD		0x80
88 #define	AMDSB_WD_COUNT			0x04
89 #define		AMDSB_WD_COUNT_MASK	0xffff
90 #define	AMDSB_WDIO_REG_WIDTH		4
91 /* WDRT */
92 #define	MAXCOUNT_MIN_VALUE		511
93 /* RRG 2.3.1.1, page 122; SB600 RRG 2.3.1.1, page 97. */
94 #define	AMDSB7xx_SMBUS_DEVID		0x43851002
95 
96 #define	amdsbwd_verbose_printf(dev, ...)	\
97 	do {						\
98 		if (bootverbose)			\
99 			device_printf(dev, __VA_ARGS__);\
100 	} while (0)
101 
102 struct amdsbwd_softc {
103 	device_t		dev;
104 	eventhandler_tag	ev_tag;
105 	struct resource		*res_ctrl;
106 	struct resource		*res_count;
107 	int			rid_ctrl;
108 	int			rid_count;
109 	int			ms_per_tick;
110 	int			max_ticks;
111 	int			active;
112 	unsigned int		timeout;
113 };
114 
115 static void	amdsbwd_identify(driver_t *driver, device_t parent);
116 static int	amdsbwd_probe(device_t dev);
117 static int	amdsbwd_attach(device_t dev);
118 static int	amdsbwd_detach(device_t dev);
119 
120 static device_method_t amdsbwd_methods[] = {
121 	DEVMETHOD(device_identify,	amdsbwd_identify),
122 	DEVMETHOD(device_probe,		amdsbwd_probe),
123 	DEVMETHOD(device_attach,	amdsbwd_attach),
124 	DEVMETHOD(device_detach,	amdsbwd_detach),
125 #if 0
126 	DEVMETHOD(device_shutdown,	amdsbwd_detach),
127 #endif
128 	{0, 0}
129 };
130 
131 static devclass_t	amdsbwd_devclass;
132 static driver_t		amdsbwd_driver = {
133 	"amdsbwd",
134 	amdsbwd_methods,
135 	sizeof(struct amdsbwd_softc)
136 };
137 
138 DRIVER_MODULE(amdsbwd, isa, amdsbwd_driver, amdsbwd_devclass, NULL, NULL);
139 
140 
141 static uint8_t
142 pmio_read(struct resource *res, uint8_t reg)
143 {
144 	bus_write_1(res, 0, reg);	/* Index */
145 	return (bus_read_1(res, 1));	/* Data */
146 }
147 
148 static void
149 pmio_write(struct resource *res, uint8_t reg, uint8_t val)
150 {
151 	bus_write_1(res, 0, reg);	/* Index */
152 	bus_write_1(res, 1, val);	/* Data */
153 }
154 
155 static uint32_t
156 wdctrl_read(struct amdsbwd_softc *sc)
157 {
158 	return (bus_read_4(sc->res_ctrl, 0));
159 }
160 
161 static void
162 wdctrl_write(struct amdsbwd_softc *sc, uint32_t val)
163 {
164 	bus_write_4(sc->res_ctrl, 0, val);
165 }
166 
167 static __unused uint32_t
168 wdcount_read(struct amdsbwd_softc *sc)
169 {
170 	return (bus_read_4(sc->res_count, 0));
171 }
172 
173 static void
174 wdcount_write(struct amdsbwd_softc *sc, uint32_t val)
175 {
176 	bus_write_4(sc->res_count, 0, val);
177 }
178 
179 static void
180 amdsbwd_tmr_enable(struct amdsbwd_softc *sc)
181 {
182 	uint32_t val;
183 
184 	val = wdctrl_read(sc);
185 	val |= AMDSB_WD_RUN;
186 	wdctrl_write(sc, val);
187 	sc->active = 1;
188 	amdsbwd_verbose_printf(sc->dev, "timer enabled\n");
189 }
190 
191 static void
192 amdsbwd_tmr_disable(struct amdsbwd_softc *sc)
193 {
194 	uint32_t val;
195 
196 	val = wdctrl_read(sc);
197 	val &= ~AMDSB_WD_RUN;
198 	wdctrl_write(sc, val);
199 	sc->active = 0;
200 	amdsbwd_verbose_printf(sc->dev, "timer disabled\n");
201 }
202 
203 static void
204 amdsbwd_tmr_reload(struct amdsbwd_softc *sc)
205 {
206 	uint32_t val;
207 
208 	val = wdctrl_read(sc);
209 	val |= AMDSB_WD_RELOAD;
210 	wdctrl_write(sc, val);
211 }
212 
213 static void
214 amdsbwd_tmr_set(struct amdsbwd_softc *sc, uint16_t timeout)
215 {
216 
217 	timeout &= AMDSB_WD_COUNT_MASK;
218 	wdcount_write(sc, timeout);
219 	sc->timeout = timeout;
220 	amdsbwd_verbose_printf(sc->dev, "timeout set to %u ticks\n", timeout);
221 }
222 
223 static void
224 amdsbwd_event(void *arg, unsigned int cmd, int *error)
225 {
226 	struct amdsbwd_softc *sc = arg;
227 	unsigned int timeout;
228 
229 	/* convert from power-of-two-ns to WDT ticks */
230 	cmd &= WD_INTERVAL;
231 	if (cmd < WD_TO_1SEC)
232 		cmd = 0;
233 	if (cmd) {
234 		timeout = ((uint64_t)1 << (cmd - WD_TO_1MS)) / sc->ms_per_tick;
235 		if (timeout > sc->max_ticks)
236 			timeout = sc->max_ticks;
237 		if (timeout != sc->timeout) {
238 			amdsbwd_tmr_set(sc, timeout);
239 			if (!sc->active)
240 				amdsbwd_tmr_enable(sc);
241 		}
242 		amdsbwd_tmr_reload(sc);
243 		*error = 0;
244 	} else {
245 		if (sc->active)
246 			amdsbwd_tmr_disable(sc);
247 	}
248 }
249 
250 static void
251 amdsbwd_identify(driver_t *driver, device_t parent)
252 {
253 	device_t		child;
254 	device_t		smb_dev;
255 
256 	if (resource_disabled("amdsbwd", 0))
257 		return;
258 	if (device_find_child(parent, "amdsbwd", -1) != NULL)
259 		return;
260 
261 	/*
262 	 * Try to identify SB600/SB7xx by PCI Device ID of SMBus device
263 	 * that should be present at bus 0, device 20, function 0.
264 	 */
265 	smb_dev = pci_find_bsf(0, 20, 0);
266 	if (smb_dev == NULL)
267 		return;
268 	if (pci_get_devid(smb_dev) != AMDSB7xx_SMBUS_DEVID)
269 		return;
270 
271 	child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "amdsbwd", -1);
272 	if (child == NULL)
273 		device_printf(parent, "add amdsbwd child failed\n");
274 }
275 
276 static int
277 amdsbwd_probe(device_t dev)
278 {
279 	struct resource		*res;
280 	uint32_t		addr;
281 	uint32_t		val;
282 	int			rid;
283 	int			rc;
284 	int			i;
285 
286 	/* Do not claim some ISA PnP device by accident. */
287 	if (isa_get_logicalid(dev) != 0)
288 		return (ENXIO);
289 
290 	rc = bus_set_resource(dev, SYS_RES_IOPORT, 0, AMDSB_PMIO_INDEX,
291 	    AMDSB_PMIO_WIDTH);
292 	if (rc != 0) {
293 		device_printf(dev, "bus_set_resource for IO failed\n");
294 		return (ENXIO);
295 	}
296 	rid = 0;
297 	res = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid, 0ul, ~0ul,
298 	    AMDSB_PMIO_WIDTH, RF_ACTIVE | RF_SHAREABLE);
299 	if (res == NULL) {
300 		device_printf(dev, "bus_alloc_resource for IO failed\n");
301 		return (ENXIO);
302 	}
303 
304 	/* Report cause of previous reset for user's convenience. */
305 	val = pmio_read(res, AMDSB_PM_RESET_STATUS0);
306 	if (val != 0)
307 		amdsbwd_verbose_printf(dev, "ResetStatus0 = %#04x\n", val);
308 	val = pmio_read(res, AMDSB_PM_RESET_STATUS1);
309 	if (val != 0)
310 		amdsbwd_verbose_printf(dev, "ResetStatus1 = %#04x\n", val);
311 	if ((val & AMDSB_WD_RST_STS) != 0)
312 		device_printf(dev, "Previous Reset was caused by Watchdog\n");
313 
314 	/* Find base address of memory mapped WDT registers. */
315 	for (addr = 0, i = 0; i < 4; i++) {
316 		addr <<= 8;
317 		addr |= pmio_read(res, AMDSB_PM_WDT_BASE_MSB - i);
318 	}
319 	amdsbwd_verbose_printf(dev, "memory base address = %#010x\n", addr);
320 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 0, addr + AMDSB_WD_CTRL,
321 	    AMDSB_WDIO_REG_WIDTH);
322 	if (rc != 0) {
323 		device_printf(dev, "bus_set_resource for control failed\n");
324 		return (ENXIO);
325 	}
326 	rc = bus_set_resource(dev, SYS_RES_MEMORY, 1, addr + AMDSB_WD_COUNT,
327 	    AMDSB_WDIO_REG_WIDTH);
328 	if (rc != 0) {
329 		device_printf(dev, "bus_set_resource for count failed\n");
330 		return (ENXIO);
331 	}
332 
333 	/* Set watchdog timer tick to 10ms. */
334 	val = pmio_read(res, AMDSB_PM_WDT_CTRL);
335 	val &= ~AMDSB_WDT_RES_MASK;
336 	val |= AMDSB_WDT_RES_10MS;
337 	pmio_write(res, AMDSB_PM_WDT_CTRL, val);
338 
339 	/* Enable watchdog device (in stopped state). */
340 	val = pmio_read(res, AMDSB_PM_WDT_CTRL);
341 	val &= ~AMDSB_WDT_DISABLE;
342 	pmio_write(res, AMDSB_PM_WDT_CTRL, val);
343 
344 	/*
345 	 * XXX TODO: Ensure that watchdog decode is enabled
346 	 * (register 0x41, bit 3).
347 	 */
348 	bus_release_resource(dev, SYS_RES_IOPORT, rid, res);
349 	bus_delete_resource(dev, SYS_RES_IOPORT, rid);
350 
351 	device_set_desc(dev, "AMD SB600/SB7xx Watchdog Timer");
352 	return (0);
353 }
354 
355 static int
356 amdsbwd_attach_sb(device_t dev, struct amdsbwd_softc *sc)
357 {
358 	sc->max_ticks = UINT16_MAX;
359 	sc->ms_per_tick = 10;
360 	sc->rid_ctrl = 0;
361 	sc->rid_count = 1;
362 
363 	sc->res_ctrl = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
364 	    &sc->rid_ctrl, RF_ACTIVE);
365 	if (sc->res_ctrl == NULL) {
366 		device_printf(dev, "bus_alloc_resource for ctrl failed\n");
367 		return (ENXIO);
368 	}
369 	sc->res_count = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
370 	    &sc->rid_count, RF_ACTIVE);
371 	if (sc->res_count == NULL) {
372 		device_printf(dev, "bus_alloc_resource for count failed\n");
373 		return (ENXIO);
374 	}
375 	return (0);
376 }
377 
378 static int
379 amdsbwd_attach(device_t dev)
380 {
381 	struct amdsbwd_softc	*sc;
382 	int			rc;
383 
384 	sc = device_get_softc(dev);
385 	sc->dev = dev;
386 
387 	rc = amdsbwd_attach_sb(dev, sc);
388 	if (rc != 0)
389 		goto fail;
390 
391 	/* Setup initial state of Watchdog Control. */
392 	wdctrl_write(sc, AMDSB_WD_FIRED);
393 
394 	if (wdctrl_read(sc) & AMDSB_WD_DISABLE) {
395 		device_printf(dev, "watchdog hardware is disabled\n");
396 		goto fail;
397 	}
398 
399 	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, amdsbwd_event, sc,
400 	    EVENTHANDLER_PRI_ANY);
401 
402 	return (0);
403 
404 fail:
405 	amdsbwd_detach(dev);
406 	return (ENXIO);
407 }
408 
409 static int
410 amdsbwd_detach(device_t dev)
411 {
412 	struct amdsbwd_softc *sc;
413 
414 	sc = device_get_softc(dev);
415 	if (sc->ev_tag != NULL)
416 		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
417 
418 	if (sc->active)
419 		amdsbwd_tmr_disable(sc);
420 
421 	if (sc->res_ctrl != NULL)
422 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_ctrl,
423 		    sc->res_ctrl);
424 
425 	if (sc->res_count != NULL)
426 		bus_release_resource(dev, SYS_RES_MEMORY, sc->rid_count,
427 		    sc->res_count);
428 
429 	return (0);
430 }
431 
432