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 (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <sys/mutex.h>
26 #include <sys/cpuvar.h>
27 #include <sys/cyclic.h>
28 #include <sys/disp.h>
29 #include <sys/ddi.h>
30 #include <sys/wdt.h>
31 #include <sys/callb.h>
32 #include <sys/cmn_err.h>
33 #include <sys/hypervisor_api.h>
34 #include <sys/membar.h>
35 #include <sys/x_call.h>
36 #include <sys/promif.h>
37 #include <sys/systm.h>
38 #include <sys/mach_descrip.h>
39 #include <sys/cpu_module.h>
40 #include <sys/pg.h>
41 #include <sys/lgrp.h>
42 #include <sys/sysmacros.h>
43 #include <sys/sunddi.h>
44 #include <sys/cpupart.h>
45 #include <sys/hsvc.h>
46 #include <sys/mpo.h>
47 #include <vm/hat_sfmmu.h>
48 #include <sys/time.h>
49 #include <sys/clock.h>
50
51 /*
52 * Sun4v OS Suspend
53 *
54 * Provides a means to suspend a sun4v guest domain by pausing CPUs and then
55 * calling into the HV to initiate a suspension. Suspension is sequenced
56 * externally by calling suspend_pre, suspend_start, and suspend_post.
57 * suspend_pre and suspend_post are meant to perform any special operations
58 * that should be done before or after a suspend/resume operation. e.g.,
59 * callbacks to cluster software to disable heartbeat monitoring before the
60 * system is suspended. suspend_start prepares kernel services to be suspended
61 * and then suspends the domain by calling hv_guest_suspend.
62 *
63 * Special Handling for %tick and %stick Registers
64 *
65 * After a suspend/resume operation, the %tick and %stick registers may have
66 * jumped forwards or backwards. The delta is assumed to be consistent across
67 * all CPUs, within the negligible level of %tick and %stick variation
68 * acceptable on a cold boot. In order to maintain increasing %tick and %stick
69 * counter values without exposing large positive or negative jumps to kernel
70 * or user code, a %tick and %stick offset is used. Kernel reads of these
71 * counters return the sum of the hardware register counter and offset
72 * variable. After a suspend/resume operation, user reads of %tick or %stick
73 * are emulated. Suspend code enables emulation by setting the
74 * %{tick,stick}.NPT fields which trigger a privileged instruction access
75 * trap whenever the registers are read from user mode. If emulation has been
76 * enabled, the trap handler emulates the instruction. Emulation is only
77 * enabled during a successful suspend/resume operation. When emulation is
78 * enabled, CPUs that are DR'd into the system will have their
79 * %{tick,stick}.NPT bits set to 1 as well.
80 */
81
82 extern u_longlong_t gettick(void); /* returns %stick */
83 extern uint64_t gettick_counter(void); /* returns %tick */
84 extern uint64_t gettick_npt(void);
85 extern uint64_t getstick_npt(void);
86 extern int mach_descrip_update(void);
87 extern cpuset_t cpu_ready_set;
88 extern uint64_t native_tick_offset;
89 extern uint64_t native_stick_offset;
90 extern uint64_t sys_tick_freq;
91
92 /*
93 * Global Sun Cluster pre/post callbacks.
94 */
95 const char *(*cl_suspend_error_decode)(int);
96 int (*cl_suspend_pre_callback)(void);
97 int (*cl_suspend_post_callback)(void);
98 #define SC_PRE_FAIL_STR_FMT "Sun Cluster pre-suspend failure: %d"
99 #define SC_POST_FAIL_STR_FMT "Sun Cluster post-suspend failure: %d"
100 #define SC_FAIL_STR_MAX 256
101
102 /*
103 * The minimum major and minor version of the HSVC_GROUP_CORE API group
104 * required in order to use OS suspend.
105 */
106 #define SUSPEND_CORE_MAJOR 1
107 #define SUSPEND_CORE_MINOR 2
108
109 /*
110 * By default, sun4v OS suspend is supported if the required HV version
111 * is present. suspend_disabled should be set on platforms that do not
112 * allow OS suspend regardless of whether or not the HV supports it.
113 * It can also be set in /etc/system.
114 */
115 static int suspend_disabled = 0;
116
117 /*
118 * Controls whether or not user-land tick and stick register emulation
119 * will be enabled following a successful suspend operation.
120 */
121 static int enable_user_tick_stick_emulation = 1;
122
123 /*
124 * Indicates whether or not tick and stick emulation is currently active.
125 * After a successful suspend operation, if emulation is enabled, this
126 * variable is set to B_TRUE. Global scope to allow emulation code to
127 * check if emulation is active.
128 */
129 boolean_t tick_stick_emulation_active = B_FALSE;
130
131 /*
132 * When non-zero, after a successful suspend and resume, cpunodes, CPU HW
133 * sharing data structures, and processor groups will be updated using
134 * information from the updated MD.
135 */
136 static int suspend_update_cpu_mappings = 1;
137
138 /*
139 * The maximum number of microseconds by which the %tick or %stick register
140 * can vary between any two CPUs in the system. To calculate the
141 * native_stick_offset and native_tick_offset, we measure the change in these
142 * registers on one CPU over a suspend/resume. Other CPUs may experience
143 * slightly larger or smaller changes. %tick and %stick should be synchronized
144 * between CPUs, but there may be some variation. So we add an additional value
145 * derived from this variable to ensure that these registers always increase
146 * over a suspend/resume operation, assuming all %tick and %stick registers
147 * are synchronized (within a certain limit) across CPUs in the system. The
148 * delta between %sticks on different CPUs should be a small number of cycles,
149 * not perceptible to readers of %stick that migrate between CPUs. We set this
150 * value to 1 millisecond which means that over a suspend/resume operation,
151 * all CPU's %tick and %stick will advance forwards as long as, across all
152 * CPUs, the %tick and %stick are synchronized to within 1 ms. This applies to
153 * CPUs before the suspend and CPUs after the resume. 1 ms is conservative,
154 * but small enough to not trigger TOD faults.
155 */
156 static uint64_t suspend_tick_stick_max_delta = 1000; /* microseconds */
157
158 /*
159 * The number of times the system has been suspended and resumed.
160 */
161 static uint64_t suspend_count = 0;
162
163 /*
164 * DBG and DBG_PROM() macro.
165 */
166 #ifdef DEBUG
167
168 static int suspend_debug_flag = 0;
169
170 #define DBG_PROM \
171 if (suspend_debug_flag) \
172 prom_printf
173
174 #define DBG \
175 if (suspend_debug_flag) \
176 suspend_debug
177
178 static void
suspend_debug(const char * fmt,...)179 suspend_debug(const char *fmt, ...)
180 {
181 char buf[512];
182 va_list ap;
183
184 va_start(ap, fmt);
185 (void) vsprintf(buf, fmt, ap);
186 va_end(ap);
187
188 cmn_err(CE_NOTE, "%s", buf);
189 }
190
191 #else /* DEBUG */
192
193 #define DBG_PROM
194 #define DBG
195
196 #endif /* DEBUG */
197
198 /*
199 * Return true if the HV supports OS suspend and if suspend has not been
200 * disabled on this platform.
201 */
202 boolean_t
suspend_supported(void)203 suspend_supported(void)
204 {
205 uint64_t major, minor;
206
207 if (suspend_disabled)
208 return (B_FALSE);
209
210 if (hsvc_version(HSVC_GROUP_CORE, &major, &minor) != 0)
211 return (B_FALSE);
212
213 return ((major == SUSPEND_CORE_MAJOR && minor >= SUSPEND_CORE_MINOR) ||
214 (major > SUSPEND_CORE_MAJOR));
215 }
216
217 /*
218 * Memory DR is not permitted if the system has been suspended and resumed.
219 * It is the responsibility of the caller of suspend_start and the DR
220 * subsystem to serialize DR operations and suspend_memdr_allowed() checks.
221 */
222 boolean_t
suspend_memdr_allowed(void)223 suspend_memdr_allowed(void)
224 {
225 return (suspend_count == 0);
226 }
227
228 /*
229 * Given a source tick, stick, and tod value, set the tick and stick offsets
230 * such that the (current physical register value) + offset == (source value)
231 * and in addition account for some variation between the %tick/%stick on
232 * different CPUs. We account for this variation by adding in double the value
233 * of suspend_tick_stick_max_delta. The following is an explanation of why
234 * suspend_tick_stick_max_delta must be multplied by two and added to
235 * native_stick_offset.
236 *
237 * Consider a guest instance that is yet to be suspended with CPUs p0 and p1
238 * with physical "source" %stick values s0 and s1 respectively. When the guest
239 * is first resumed, the physical "target" %stick values are t0 and t1
240 * respectively. The virtual %stick values after the resume are v0 and v1
241 * respectively. Let x be the maximum difference between any two CPU's %stick
242 * register at a given point in time and let the %stick values be assigned
243 * such that
244 *
245 * s1 = s0 + x and
246 * t1 = t0 - x
247 *
248 * Let us assume that p0 is driving the suspend and resume. Then, we will
249 * calculate the stick offset f and the virtual %stick on p0 after the
250 * resume as follows.
251 *
252 * f = s0 - t0 and
253 * v0 = t0 + f
254 *
255 * We calculate the virtual %stick v1 on p1 after the resume as
256 *
257 * v1 = t1 + f
258 *
259 * Substitution yields
260 *
261 * v1 = t1 + (s0 - t0)
262 * v1 = (t0 - x) + (s0 - t0)
263 * v1 = -x + s0
264 * v1 = s0 - x
265 * v1 = (s1 - x) - x
266 * v1 = s1 - 2x
267 *
268 * Therefore, in this scenario, without accounting for %stick variation in
269 * the calculation of the native_stick_offset f, the virtual %stick on p1
270 * is less than the value of the %stick on p1 before the suspend which is
271 * unacceptable. By adding 2x to v1, we guarantee it will be equal to s1
272 * which means the %stick on p1 after the resume will always be greater
273 * than or equal to the %stick on p1 before the suspend. Since v1 = t1 + f
274 * at any point in time, we can accomplish this by adding 2x to f. This
275 * guarantees any processes bound to CPU P0 or P1 will not see a %stick
276 * decrease across a suspend/resume. Hence, in the code below, we multiply
277 * suspend_tick_stick_max_delta by two in the calculation for
278 * native_stick_offset, native_tick_offset, and target_hrtime.
279 */
280 static void
set_tick_offsets(uint64_t source_tick,uint64_t source_stick,timestruc_t * tsp)281 set_tick_offsets(uint64_t source_tick, uint64_t source_stick, timestruc_t *tsp)
282 {
283 uint64_t target_tick;
284 uint64_t target_stick;
285 hrtime_t source_hrtime;
286 hrtime_t target_hrtime;
287
288 /*
289 * Temporarily set the offsets to zero so that the following reads
290 * of the registers will yield physical unadjusted counter values.
291 */
292 native_tick_offset = 0;
293 native_stick_offset = 0;
294
295 target_tick = gettick_counter(); /* returns %tick */
296 target_stick = gettick(); /* returns %stick */
297
298 /*
299 * Calculate the new offsets. In addition to the delta observed on
300 * this CPU, add an additional value. Multiply the %tick/%stick
301 * frequency by suspend_tick_stick_max_delta (us). Then, multiply by 2
302 * to account for a delta between CPUs before the suspend and a
303 * delta between CPUs after the resume.
304 */
305 native_tick_offset = (source_tick - target_tick) +
306 (CPU->cpu_curr_clock * suspend_tick_stick_max_delta * 2 / MICROSEC);
307 native_stick_offset = (source_stick - target_stick) +
308 (sys_tick_freq * suspend_tick_stick_max_delta * 2 / MICROSEC);
309
310 /*
311 * We've effectively increased %stick and %tick by twice the value
312 * of suspend_tick_stick_max_delta to account for variation across
313 * CPUs. Now adjust the preserved TOD by the same amount.
314 */
315 source_hrtime = ts2hrt(tsp);
316 target_hrtime = source_hrtime +
317 (suspend_tick_stick_max_delta * 2 * (NANOSEC/MICROSEC));
318 hrt2ts(target_hrtime, tsp);
319 }
320
321 /*
322 * Set the {tick,stick}.NPT field to 1 on this CPU.
323 */
324 static void
enable_tick_stick_npt(void)325 enable_tick_stick_npt(void)
326 {
327 (void) hv_stick_set_npt(1);
328 (void) hv_tick_set_npt(1);
329 }
330
331 /*
332 * Synchronize a CPU's {tick,stick}.NPT fields with the current state
333 * of the system. This is used when a CPU is DR'd into the system.
334 */
335 void
suspend_sync_tick_stick_npt(void)336 suspend_sync_tick_stick_npt(void)
337 {
338 if (tick_stick_emulation_active) {
339 DBG("enabling {%%tick/%%stick}.NPT on CPU 0x%x", CPU->cpu_id);
340 (void) hv_stick_set_npt(1);
341 (void) hv_tick_set_npt(1);
342 } else {
343 ASSERT(gettick_npt() == 0);
344 ASSERT(getstick_npt() == 0);
345 }
346 }
347
348 /*
349 * Obtain an updated MD from the hypervisor and update cpunodes, CPU HW
350 * sharing data structures, and processor groups.
351 */
352 static void
update_cpu_mappings(void)353 update_cpu_mappings(void)
354 {
355 md_t *mdp;
356 processorid_t id;
357 cpu_t *cp;
358 cpu_pg_t *pgps[NCPU];
359
360 if ((mdp = md_get_handle()) == NULL) {
361 DBG("suspend: md_get_handle failed");
362 return;
363 }
364
365 DBG("suspend: updating CPU mappings");
366
367 mutex_enter(&cpu_lock);
368
369 setup_chip_mappings(mdp);
370 setup_exec_unit_mappings(mdp);
371 for (id = 0; id < NCPU; id++) {
372 if ((cp = cpu_get(id)) == NULL)
373 continue;
374 cpu_map_exec_units(cp);
375 }
376
377 /*
378 * Re-calculate processor groups.
379 *
380 * First tear down all PG information before adding any new PG
381 * information derived from the MD we just downloaded. We must
382 * call pg_cpu_inactive and pg_cpu_active with CPUs paused and
383 * we want to minimize the number of times pause_cpus is called.
384 * Inactivating all CPUs would leave PGs without any active CPUs,
385 * so while CPUs are paused, call pg_cpu_inactive and swap in the
386 * bootstrap PG structure saving the original PG structure to be
387 * fini'd afterwards. This prevents the dispatcher from encountering
388 * PGs in which all CPUs are inactive. Offline CPUs are already
389 * inactive in their PGs and shouldn't be reactivated, so we must
390 * not call pg_cpu_inactive or pg_cpu_active for those CPUs.
391 */
392 pause_cpus(NULL, NULL);
393 for (id = 0; id < NCPU; id++) {
394 if ((cp = cpu_get(id)) == NULL)
395 continue;
396 if ((cp->cpu_flags & CPU_OFFLINE) == 0)
397 pg_cpu_inactive(cp);
398 pgps[id] = cp->cpu_pg;
399 pg_cpu_bootstrap(cp);
400 }
401 start_cpus();
402
403 /*
404 * pg_cpu_fini* and pg_cpu_init* must be called while CPUs are
405 * not paused. Use two separate loops here so that we do not
406 * initialize PG data for CPUs until all the old PG data structures
407 * are torn down.
408 */
409 for (id = 0; id < NCPU; id++) {
410 if ((cp = cpu_get(id)) == NULL)
411 continue;
412 pg_cpu_fini(cp, pgps[id]);
413 mpo_cpu_remove(id);
414 }
415
416 /*
417 * Initialize PG data for each CPU, but leave the bootstrapped
418 * PG structure in place to avoid running with any PGs containing
419 * nothing but inactive CPUs.
420 */
421 for (id = 0; id < NCPU; id++) {
422 if ((cp = cpu_get(id)) == NULL)
423 continue;
424 mpo_cpu_add(mdp, id);
425 pgps[id] = pg_cpu_init(cp, B_TRUE);
426 }
427
428 /*
429 * Now that PG data has been initialized for all CPUs in the
430 * system, replace the bootstrapped PG structure with the
431 * initialized PG structure and call pg_cpu_active for each CPU.
432 */
433 pause_cpus(NULL, NULL);
434 for (id = 0; id < NCPU; id++) {
435 if ((cp = cpu_get(id)) == NULL)
436 continue;
437 cp->cpu_pg = pgps[id];
438 if ((cp->cpu_flags & CPU_OFFLINE) == 0)
439 pg_cpu_active(cp);
440 }
441 start_cpus();
442
443 mutex_exit(&cpu_lock);
444
445 (void) md_fini_handle(mdp);
446 }
447
448 /*
449 * Wrapper for the Sun Cluster error decoding function.
450 */
451 static int
cluster_error_decode(int error,char * error_reason,size_t max_reason_len)452 cluster_error_decode(int error, char *error_reason, size_t max_reason_len)
453 {
454 const char *decoded;
455 size_t decoded_len;
456
457 ASSERT(error_reason != NULL);
458 ASSERT(max_reason_len > 0);
459
460 max_reason_len = MIN(max_reason_len, SC_FAIL_STR_MAX);
461
462 if (cl_suspend_error_decode == NULL)
463 return (-1);
464
465 if ((decoded = (*cl_suspend_error_decode)(error)) == NULL)
466 return (-1);
467
468 /* Get number of non-NULL bytes */
469 if ((decoded_len = strnlen(decoded, max_reason_len - 1)) == 0)
470 return (-1);
471
472 bcopy(decoded, error_reason, decoded_len);
473
474 /*
475 * The error string returned from cl_suspend_error_decode
476 * should be NULL-terminated, but set the terminator here
477 * because we only copied non-NULL bytes. If the decoded
478 * string was not NULL-terminated, this guarantees that
479 * error_reason will be.
480 */
481 error_reason[decoded_len] = '\0';
482
483 return (0);
484 }
485
486 /*
487 * Wrapper for the Sun Cluster pre-suspend callback.
488 */
489 static int
cluster_pre_wrapper(char * error_reason,size_t max_reason_len)490 cluster_pre_wrapper(char *error_reason, size_t max_reason_len)
491 {
492 int rv = 0;
493
494 if (cl_suspend_pre_callback != NULL) {
495 rv = (*cl_suspend_pre_callback)();
496 DBG("suspend: cl_suspend_pre_callback returned %d", rv);
497 if (rv != 0 && error_reason != NULL && max_reason_len > 0) {
498 if (cluster_error_decode(rv, error_reason,
499 max_reason_len)) {
500 (void) snprintf(error_reason, max_reason_len,
501 SC_PRE_FAIL_STR_FMT, rv);
502 }
503 }
504 }
505
506 return (rv);
507 }
508
509 /*
510 * Wrapper for the Sun Cluster post-suspend callback.
511 */
512 static int
cluster_post_wrapper(char * error_reason,size_t max_reason_len)513 cluster_post_wrapper(char *error_reason, size_t max_reason_len)
514 {
515 int rv = 0;
516
517 if (cl_suspend_post_callback != NULL) {
518 rv = (*cl_suspend_post_callback)();
519 DBG("suspend: cl_suspend_post_callback returned %d", rv);
520 if (rv != 0 && error_reason != NULL && max_reason_len > 0) {
521 if (cluster_error_decode(rv, error_reason,
522 max_reason_len)) {
523 (void) snprintf(error_reason,
524 max_reason_len, SC_POST_FAIL_STR_FMT, rv);
525 }
526 }
527 }
528
529 return (rv);
530 }
531
532 /*
533 * Execute pre-suspend callbacks preparing the system for a suspend operation.
534 * Returns zero on success, non-zero on failure. Sets the recovered argument
535 * to indicate whether or not callbacks could be undone in the event of a
536 * failure--if callbacks were successfully undone, *recovered is set to B_TRUE,
537 * otherwise *recovered is set to B_FALSE. Must be called successfully before
538 * suspend_start can be called. Callers should first call suspend_support to
539 * determine if OS suspend is supported.
540 */
541 int
suspend_pre(char * error_reason,size_t max_reason_len,boolean_t * recovered)542 suspend_pre(char *error_reason, size_t max_reason_len, boolean_t *recovered)
543 {
544 int rv;
545
546 ASSERT(recovered != NULL);
547
548 /*
549 * Return an error if suspend_pre is erreoneously called
550 * when OS suspend is not supported.
551 */
552 ASSERT(suspend_supported());
553 if (!suspend_supported()) {
554 DBG("suspend: suspend_pre called without suspend support");
555 *recovered = B_TRUE;
556 return (ENOTSUP);
557 }
558 DBG("suspend: %s", __func__);
559
560 rv = cluster_pre_wrapper(error_reason, max_reason_len);
561
562 /*
563 * At present, only one pre-suspend operation exists.
564 * If it fails, no recovery needs to be done.
565 */
566 if (rv != 0 && recovered != NULL)
567 *recovered = B_TRUE;
568
569 return (rv);
570 }
571
572 /*
573 * Execute post-suspend callbacks. Returns zero on success, non-zero on
574 * failure. Must be called after suspend_start is called, regardless of
575 * whether or not suspend_start is successful.
576 */
577 int
suspend_post(char * error_reason,size_t max_reason_len)578 suspend_post(char *error_reason, size_t max_reason_len)
579 {
580 ASSERT(suspend_supported());
581 DBG("suspend: %s", __func__);
582 return (cluster_post_wrapper(error_reason, max_reason_len));
583 }
584
585 /*
586 * Suspends the OS by pausing CPUs and calling into the HV to initiate
587 * the suspend. When the HV routine hv_guest_suspend returns, the system
588 * will be resumed. Must be called after a successful call to suspend_pre.
589 * suspend_post must be called after suspend_start, whether or not
590 * suspend_start returns an error.
591 */
592 /*ARGSUSED*/
593 int
suspend_start(char * error_reason,size_t max_reason_len)594 suspend_start(char *error_reason, size_t max_reason_len)
595 {
596 uint64_t source_tick;
597 uint64_t source_stick;
598 uint64_t rv;
599 timestruc_t source_tod;
600 int spl;
601
602 ASSERT(suspend_supported());
603 DBG("suspend: %s", __func__);
604
605 sfmmu_ctxdoms_lock();
606
607 mutex_enter(&cpu_lock);
608
609 /* Suspend the watchdog */
610 watchdog_suspend();
611
612 /* Record the TOD */
613 mutex_enter(&tod_lock);
614 source_tod = tod_get();
615 mutex_exit(&tod_lock);
616
617 /* Pause all other CPUs */
618 pause_cpus(NULL, NULL);
619 DBG_PROM("suspend: CPUs paused\n");
620
621 /* Suspend cyclics */
622 cyclic_suspend();
623 DBG_PROM("suspend: cyclics suspended\n");
624
625 /* Disable interrupts */
626 spl = spl8();
627 DBG_PROM("suspend: spl8()\n");
628
629 source_tick = gettick_counter();
630 source_stick = gettick();
631 DBG_PROM("suspend: source_tick: 0x%lx\n", source_tick);
632 DBG_PROM("suspend: source_stick: 0x%lx\n", source_stick);
633
634 /*
635 * Call into the HV to initiate the suspend. hv_guest_suspend()
636 * returns after the guest has been resumed or if the suspend
637 * operation failed or was cancelled. After a successful suspend,
638 * the %tick and %stick registers may have changed by an amount
639 * that is not proportional to the amount of time that has passed.
640 * They may have jumped forwards or backwards. Some variation is
641 * allowed and accounted for using suspend_tick_stick_max_delta,
642 * but otherwise this jump must be uniform across all CPUs and we
643 * operate under the assumption that it is (maintaining two global
644 * offset variables--one for %tick and one for %stick.)
645 */
646 DBG_PROM("suspend: suspending... \n");
647 rv = hv_guest_suspend();
648 if (rv != 0) {
649 splx(spl);
650 cyclic_resume();
651 start_cpus();
652 watchdog_resume();
653 mutex_exit(&cpu_lock);
654 sfmmu_ctxdoms_unlock();
655 DBG("suspend: failed, rv: %ld\n", rv);
656 return (rv);
657 }
658
659 suspend_count++;
660
661 /* Update the global tick and stick offsets and the preserved TOD */
662 set_tick_offsets(source_tick, source_stick, &source_tod);
663
664 /* Ensure new offsets are globally visible before resuming CPUs */
665 membar_sync();
666
667 /* Enable interrupts */
668 splx(spl);
669
670 /* Set the {%tick,%stick}.NPT bits on all CPUs */
671 if (enable_user_tick_stick_emulation) {
672 xc_all((xcfunc_t *)enable_tick_stick_npt, 0, 0);
673 xt_sync(cpu_ready_set);
674 ASSERT(gettick_npt() != 0);
675 ASSERT(getstick_npt() != 0);
676 }
677
678 /* If emulation is enabled, but not currently active, enable it */
679 if (enable_user_tick_stick_emulation && !tick_stick_emulation_active) {
680 tick_stick_emulation_active = B_TRUE;
681 }
682
683 sfmmu_ctxdoms_remove();
684
685 /* Resume cyclics, unpause CPUs */
686 cyclic_resume();
687 start_cpus();
688
689 /* Set the TOD */
690 mutex_enter(&tod_lock);
691 tod_set(source_tod);
692 mutex_exit(&tod_lock);
693
694 /* Re-enable the watchdog */
695 watchdog_resume();
696
697 mutex_exit(&cpu_lock);
698
699 /* Download the latest MD */
700 if ((rv = mach_descrip_update()) != 0)
701 cmn_err(CE_PANIC, "suspend: mach_descrip_update failed: %ld",
702 rv);
703
704 sfmmu_ctxdoms_update();
705 sfmmu_ctxdoms_unlock();
706
707 /* Get new MD, update CPU mappings/relationships */
708 if (suspend_update_cpu_mappings)
709 update_cpu_mappings();
710
711 DBG("suspend: target tick: 0x%lx", gettick_counter());
712 DBG("suspend: target stick: 0x%llx", gettick());
713 DBG("suspend: user %%tick/%%stick emulation is %d",
714 tick_stick_emulation_active);
715 DBG("suspend: finished");
716
717 return (0);
718 }
719