xref: /titanic_41/usr/src/uts/sun4u/io/todblade.c (revision 0dc2366f7b9f9f36e10909b1e95edbf2a261c2ac)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/conf.h>
28 #include <sys/kmem.h>
29 #include <sys/open.h>
30 #include <sys/ddi.h>
31 #include <sys/sunddi.h>
32 
33 #include <sys/todm5819.h>
34 #include <sys/modctl.h>
35 #include <sys/stat.h>
36 #include <sys/clock.h>
37 #include <sys/reboot.h>
38 #include <sys/machsystm.h>
39 #include <sys/poll.h>
40 #include <sys/pbio.h>
41 #include <sys/lom_priv.h>
42 
43 #define	WDOG_ON 1
44 #define	WDOG_OFF 0
45 
46 static timestruc_t	todbl_get(void);
47 static void		todbl_set(timestruc_t);
48 static uint_t		todbl_set_watchdog_timer(uint_t);
49 static uint_t		todbl_clear_watchdog_timer(void);
50 static void		todbl_set_power_alarm(timestruc_t);
51 static void		todbl_clear_power_alarm(void);
52 static uint64_t		todbl_get_cpufrequency(void);
53 
54 static todinfo_t	rtc_to_tod(struct rtc_t *);
55 static uint_t		read_rtc(struct rtc_t *);
56 static void		write_rtc_time(struct rtc_t *);
57 static uint_t		configure_wdog(uint8_t new_state);
58 
59 extern uint64_t		find_cpufrequency(volatile uint8_t *);
60 
61 /*
62  * External variables
63  */
64 extern int	watchdog_enable;
65 extern int	watchdog_available;
66 extern int	watchdog_activated;
67 extern uint_t   watchdog_timeout_seconds;
68 extern int	boothowto;
69 extern void	(*bsc_drv_func_ptr)(struct bscv_idi_info *);
70 
71 /*
72  * Global variables
73  */
74 int m5819_debug_flags;
75 uint8_t wdog_reset_on_timeout = 1;
76 static clock_t last_pat_lbt;
77 
78 
79 static struct modlmisc modlmisc = {
80 	&mod_miscops, "todblade module",
81 };
82 
83 static struct modlinkage modlinkage = {
84 	MODREV_1, &modlmisc, NULL
85 };
86 
87 
88 int
89 _init(void)
90 {
91 	if (strcmp(tod_module_name, "todblade") == 0) {
92 		RTC_PUT8(RTC_B, (RTC_DM | RTC_HM));
93 
94 		tod_ops.tod_get = todbl_get;
95 		tod_ops.tod_set = todbl_set;
96 		tod_ops.tod_set_watchdog_timer = todbl_set_watchdog_timer;
97 		tod_ops.tod_clear_watchdog_timer = todbl_clear_watchdog_timer;
98 		tod_ops.tod_set_power_alarm = todbl_set_power_alarm;
99 		tod_ops.tod_clear_power_alarm = todbl_clear_power_alarm;
100 		tod_ops.tod_get_cpufrequency = todbl_get_cpufrequency;
101 
102 		if (watchdog_enable && (boothowto & RB_DEBUG)) {
103 				watchdog_available = 0;
104 				cmn_err(CE_WARN, "todblade: kernel debugger "
105 				    "detected: hardware watchdog disabled");
106 		}
107 	}
108 	return (mod_install(&modlinkage));
109 }
110 
111 int
112 _fini(void)
113 {
114 	if (strcmp(tod_module_name, "todblade") == 0) {
115 		return (EBUSY);
116 	} else {
117 		return (mod_remove(&modlinkage));
118 	}
119 }
120 
121 /*
122  * The loadable-module _info(9E) entry point
123  */
124 int
125 _info(struct modinfo *modinfop)
126 {
127 	return (mod_info(&modlinkage, modinfop));
128 }
129 
130 
131 /*
132  * Read the current time from the clock chip and convert to UNIX form.
133  * Assumes that the year in the clock chip is valid.
134  * Must be called with tod_lock held.
135  */
136 static timestruc_t
137 todbl_get(void)
138 {
139 	int i;
140 	timestruc_t ts;
141 	struct rtc_t rtc;
142 	struct bscv_idi_info bscv_info;
143 
144 	ASSERT(MUTEX_HELD(&tod_lock));
145 
146 	/*
147 	 * We must check that the value of watchdog enable hasnt changed
148 	 * as its a user knob for turning it on and off
149 	 */
150 	if (watchdog_available) {
151 		if (watchdog_activated && !watchdog_enable) {
152 			(void) configure_wdog(WDOG_OFF);
153 		} else if (!watchdog_activated && watchdog_enable) {
154 			(void) configure_wdog(WDOG_ON);
155 		} else if (watchdog_activated &&
156 		    (ddi_get_lbolt() - last_pat_lbt) >= SEC_TO_TICK(1)) {
157 			/*
158 			 * PAT THE WATCHDOG!!
159 			 * We dont want to accelerate the pat frequency
160 			 * when userland calls to the TOD_GET_DATE ioctl
161 			 * pass through here.
162 			 */
163 			bscv_info.type = BSCV_IDI_WDOG_PAT;
164 			bscv_info.data = NULL;
165 			bscv_info.size = 0;
166 			if (bsc_drv_func_ptr != NULL) {
167 				(*bsc_drv_func_ptr)(&bscv_info);
168 				last_pat_lbt = ddi_get_lbolt();
169 			}
170 		}
171 	}
172 
173 	/*
174 	 * Read from the tod, and if it isnt accessible wait
175 	 * before retrying.
176 	 */
177 	for (i = 0; i < TODM5819_UIP_RETRY_THRESH; i++) {
178 		if (read_rtc(&rtc))
179 			break;
180 		drv_usecwait(TODM5819_UIP_WAIT_USEC);
181 	}
182 	if (i == TODM5819_UIP_RETRY_THRESH) {
183 		/*
184 		 * We couldn't read from the TOD.
185 		 */
186 		tod_status_set(TOD_GET_FAILED);
187 		return (hrestime);
188 	}
189 
190 	DPRINTF("todbl_get: century=%d year=%d dom=%d hrs=%d\n",
191 	    rtc.rtc_century, rtc.rtc_year, rtc.rtc_dom, rtc.rtc_hrs);
192 
193 	/* read was successful so ensure failure flag is clear */
194 	tod_status_clear(TOD_GET_FAILED);
195 
196 	ts.tv_sec = tod_to_utc(rtc_to_tod(&rtc));
197 	ts.tv_nsec = 0;
198 	return (ts);
199 }
200 
201 static todinfo_t
202 rtc_to_tod(struct rtc_t *rtc)
203 {
204 	todinfo_t tod;
205 
206 	/*
207 	 * tod_year is base 1900 so this code needs to adjust the true
208 	 * year retrieved from the rtc's century and year fields.
209 	 */
210 	tod.tod_year	= rtc->rtc_year + (rtc->rtc_century * 100) - 1900;
211 	tod.tod_month	= rtc->rtc_mon;
212 	tod.tod_day	= rtc->rtc_dom;
213 	tod.tod_dow	= rtc->rtc_dow;
214 	tod.tod_hour	= rtc->rtc_hrs;
215 	tod.tod_min	= rtc->rtc_min;
216 	tod.tod_sec	= rtc->rtc_sec;
217 
218 	return (tod);
219 }
220 
221 
222 static uint_t
223 read_rtc(struct rtc_t *rtc)
224 {
225 	int s;
226 	uint_t rtc_readable = 0;
227 
228 	s = splhi();
229 	/*
230 	 * If UIP bit is not set we have at least 274us
231 	 * to read the values.
232 	 */
233 	if (!(RTC_GET8(RTC_A) & RTC_UIP)) {
234 		rtc_readable = 1;
235 
236 		rtc->rtc_sec = RTC_GET8(RTC_SEC);
237 		rtc->rtc_asec = RTC_GET8(RTC_ASEC);
238 		rtc->rtc_min = RTC_GET8(RTC_MIN);
239 		rtc->rtc_amin = RTC_GET8(RTC_AMIN);
240 
241 		rtc->rtc_hrs = RTC_GET8(RTC_HRS);
242 		rtc->rtc_ahrs = RTC_GET8(RTC_AHRS);
243 		rtc->rtc_dow = RTC_GET8(RTC_DOW);
244 		rtc->rtc_dom = RTC_GET8(RTC_DOM);
245 		rtc->rtc_adom = RTC_GET8(RTC_D) & 0x3f;
246 
247 		rtc->rtc_mon = RTC_GET8(RTC_MON);
248 		rtc->rtc_year = RTC_GET8(RTC_YEAR);
249 		rtc->rtc_century = RTC_GET8(RTC_CENTURY);
250 		rtc->rtc_amon = 0;
251 
252 		/* Clear wakeup data */
253 		rtc->apc_wdwr = 0;
254 		rtc->apc_wdmr = 0;
255 		rtc->apc_wmr = 0;
256 		rtc->apc_wyr = 0;
257 		rtc->apc_wcr = 0;
258 	}
259 
260 	splx(s);
261 	return (rtc_readable);
262 }
263 
264 /*
265  * Write the specified time into the clock chip.
266  * Must be called with tod_lock held.
267  */
268 static void
269 todbl_set(timestruc_t ts)
270 {
271 	struct rtc_t	rtc;
272 	todinfo_t tod = utc_to_tod(ts.tv_sec);
273 	struct bscv_idi_info bscv_info;
274 	int year;
275 
276 	ASSERT(MUTEX_HELD(&tod_lock));
277 
278 	/* tod_year is base 1900 so this code needs to adjust */
279 	year = 1900 + tod.tod_year;
280 	rtc.rtc_year	= year % 100;
281 	rtc.rtc_century = year / 100;
282 	rtc.rtc_mon	= (uint8_t)tod.tod_month;
283 	rtc.rtc_dom	= (uint8_t)tod.tod_day;
284 	rtc.rtc_dow	= (uint8_t)tod.tod_dow;
285 	rtc.rtc_hrs	= (uint8_t)tod.tod_hour;
286 	rtc.rtc_min	= (uint8_t)tod.tod_min;
287 	rtc.rtc_sec	= (uint8_t)tod.tod_sec;
288 	DPRINTF("todbl_set: century=%d year=%d dom=%d hrs=%d\n",
289 	    rtc.rtc_century, rtc.rtc_year, rtc.rtc_dom, rtc.rtc_hrs);
290 
291 	write_rtc_time(&rtc);
292 
293 	/*
294 	 * Because of a generic solaris problem where calls to stime()
295 	 * starve calls to tod_get(), we need to check to see when the
296 	 * watchdog was last patted and pat it if necessary.
297 	 */
298 	if (watchdog_activated &&
299 	    (ddi_get_lbolt() - last_pat_lbt) >= SEC_TO_TICK(1)) {
300 		/*
301 		 * Pat the watchdog!
302 		 */
303 		bscv_info.type = BSCV_IDI_WDOG_PAT;
304 		bscv_info.data = NULL;
305 		bscv_info.size = 0;
306 		if (bsc_drv_func_ptr != NULL) {
307 			(*bsc_drv_func_ptr)(&bscv_info);
308 			last_pat_lbt = ddi_get_lbolt();
309 		}
310 	}
311 }
312 
313 static void
314 write_rtc_time(struct rtc_t *rtc)
315 {
316 	uint8_t	regb;
317 	int	i;
318 
319 	/*
320 	 * Freeze
321 	 */
322 	regb = RTC_GET8(RTC_B);
323 	RTC_PUT8(RTC_B, (regb | RTC_SET));
324 
325 	/*
326 	 * If an update is in progress wait for the UIP flag to clear.
327 	 * If we write whilst UIP is still set there is a slight but real
328 	 * possibility of corrupting the RTC date and time registers.
329 	 *
330 	 * The expected wait is one internal cycle of the chip.  We could
331 	 * simply spin but this may hang a CPU if we were to have a broken
332 	 * RTC chip where UIP is stuck, so we use a retry loop instead.
333 	 * No critical section is needed here as the UIP flag will not be
334 	 * re-asserted until we clear RTC_SET.
335 	 */
336 	for (i = 0; i < TODM5819_UIP_RETRY_THRESH; i++) {
337 		if (!(RTC_GET8(RTC_A) & RTC_UIP)) {
338 			break;
339 		}
340 		drv_usecwait(TODM5819_UIP_WAIT_USEC);
341 	}
342 	if (i < TODM5819_UIP_RETRY_THRESH) {
343 		RTC_PUT8(RTC_SEC, (rtc->rtc_sec));
344 		RTC_PUT8(RTC_ASEC, (rtc->rtc_asec));
345 		RTC_PUT8(RTC_MIN, (rtc->rtc_min));
346 		RTC_PUT8(RTC_AMIN, (rtc->rtc_amin));
347 
348 		RTC_PUT8(RTC_HRS, (rtc->rtc_hrs));
349 		RTC_PUT8(RTC_AHRS, (rtc->rtc_ahrs));
350 		RTC_PUT8(RTC_DOW, (rtc->rtc_dow));
351 		RTC_PUT8(RTC_DOM, (rtc->rtc_dom));
352 
353 		RTC_PUT8(RTC_MON, (rtc->rtc_mon));
354 		RTC_PUT8(RTC_YEAR, (rtc->rtc_year));
355 		RTC_PUT8(RTC_CENTURY, (rtc->rtc_century));
356 	} else {
357 		cmn_err(CE_WARN, "todblade: Could not write the RTC\n");
358 	}
359 
360 	/*
361 	 * Unfreeze
362 	 */
363 	RTC_PUT8(RTC_B, regb);
364 }
365 
366 
367 
368 /*
369  * The TOD alarm functionality is not supported on our platform
370  * as the interrupt is not wired, so do nothing.
371  */
372 /*ARGSUSED*/
373 static void
374 todbl_set_power_alarm(timestruc_t ts)
375 {
376 	ASSERT(MUTEX_HELD(&tod_lock));
377 }
378 
379 /*
380  * clear alarm interrupt
381  */
382 static void
383 todbl_clear_power_alarm(void)
384 {
385 	ASSERT(MUTEX_HELD(&tod_lock));
386 }
387 
388 /*
389  * Determine the cpu frequency by watching the TOD chip rollover twice.
390  * Cpu clock rate is determined by computing the ticks added (in tick register)
391  * during one second interval on TOD.
392  */
393 uint64_t
394 todbl_get_cpufrequency(void)
395 {
396 	ASSERT(MUTEX_HELD(&tod_lock));
397 	M5819_ADDR_REG = RTC_SEC;
398 	return (find_cpufrequency(v_rtc_data_reg));
399 }
400 
401 
402 static uint_t
403 todbl_set_watchdog_timer(uint_t timeoutval)
404 {
405 	/*
406 	 * We get started during kernel intilaisation only
407 	 * if watchdog_enable is set.
408 	 */
409 	ASSERT(MUTEX_HELD(&tod_lock));
410 
411 	if (watchdog_available && (!watchdog_activated ||
412 	    (watchdog_activated && (timeoutval != watchdog_timeout_seconds)))) {
413 		watchdog_timeout_seconds = timeoutval;
414 		if (configure_wdog(WDOG_ON))
415 			return (watchdog_timeout_seconds);
416 	}
417 	return (0);
418 }
419 
420 static uint_t
421 todbl_clear_watchdog_timer(void)
422 {
423 	/*
424 	 * The core kernel will call us here to disable the wdog when:
425 	 * 1. we're panicing
426 	 * 2. we're entering debug
427 	 * 3. we're rebooting
428 	 */
429 	ASSERT(MUTEX_HELD(&tod_lock));
430 
431 	if (watchdog_available && watchdog_activated) {
432 		watchdog_enable = 0;
433 		if (!configure_wdog(WDOG_OFF))
434 			return (0);
435 	}
436 	return (watchdog_timeout_seconds);
437 }
438 
439 static uint_t
440 configure_wdog(uint8_t new_state)
441 {
442 	bscv_wdog_t wdog_cmd;
443 	struct bscv_idi_info bscv_info;
444 
445 	if (new_state == WDOG_ON || new_state == WDOG_OFF) {
446 
447 		wdog_cmd.enable_wdog = new_state;
448 		wdog_cmd.wdog_timeout_s = watchdog_timeout_seconds;
449 		wdog_cmd.reset_system_on_timeout = wdog_reset_on_timeout;
450 		bscv_info.type = BSCV_IDI_WDOG_CFG;
451 		bscv_info.data = &wdog_cmd;
452 		bscv_info.size = sizeof (wdog_cmd);
453 
454 		if (bsc_drv_func_ptr != NULL) {
455 			watchdog_activated = new_state;
456 			(*bsc_drv_func_ptr)(&bscv_info);
457 			return (1);
458 		}
459 	}
460 	return (0);
461 
462 }
463