xref: /titanic_41/usr/src/uts/sun4/os/mp_startup.c (revision b02e9a2d4d2071d770e5aa9ae8f83f2bbe1f2ced)
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 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/sysmacros.h>
30 #include <sys/prom_plat.h>
31 #include <sys/prom_debug.h>
32 #include <vm/hat_sfmmu.h>
33 #include <vm/seg_kp.h>
34 #include <vm/seg_kmem.h>
35 #include <sys/machsystm.h>
36 #include <sys/callb.h>
37 #include <sys/cpu_module.h>
38 #include <sys/pg.h>
39 #include <sys/cmt.h>
40 #include <sys/dtrace.h>
41 #include <sys/reboot.h>
42 #include <sys/kdi.h>
43 #include <sys/traptrace.h>
44 #ifdef TRAPTRACE
45 #include <sys/bootconf.h>
46 #endif /* TRAPTRACE */
47 #include <sys/cpu_sgnblk_defs.h>
48 
49 extern int cpu_intrq_setup(struct cpu *);
50 extern void cpu_intrq_cleanup(struct cpu *);
51 extern void cpu_intrq_register(struct cpu *);
52 
53 struct cpu	*cpus;	/* pointer to other cpus; dynamically allocate */
54 struct cpu	*cpu[NCPU];	/* pointers to all CPUs */
55 uint64_t	cpu_pa[NCPU];	/* pointers to all CPUs in PA */
56 cpu_core_t	cpu_core[NCPU];	/* cpu_core structures */
57 
58 #ifdef TRAPTRACE
59 caddr_t	ttrace_buf;	/* bop alloced traptrace for all cpus except 0 */
60 #endif /* TRAPTRACE */
61 
62 /* bit mask of cpus ready for x-calls, protected by cpu_lock */
63 cpuset_t cpu_ready_set;
64 
65 /* bit mask used to communicate with cpus during bringup */
66 static cpuset_t proxy_ready_set;
67 
68 static void	slave_startup(void);
69 
70 /*
71  * Defined in $KARCH/os/mach_mp_startup.c
72  */
73 #pragma weak init_cpu_info
74 
75 /*
76  * Amount of time (in milliseconds) we should wait before giving up on CPU
77  * initialization and assuming that the CPU we're trying to wake up is dead
78  * or out of control.
79  */
80 #define	CPU_WAKEUP_GRACE_MSEC 1000
81 
82 #ifdef	TRAPTRACE
83 /*
84  * This function sets traptrace buffers for all cpus
85  * other than boot cpu.
86  * Note that the memory at base will be allocated later.
87  */
88 caddr_t
89 trap_trace_alloc(caddr_t base)
90 {
91 	caddr_t	vaddr;
92 	extern int max_ncpus;
93 
94 	if (max_ncpus == 1) {
95 		return (base);
96 	}
97 
98 	vaddr = (caddr_t)base;
99 
100 	ttrace_buf = vaddr;
101 	PRM_DEBUG(ttrace_buf);
102 	return (vaddr + (TRAP_TSIZE * (max_ncpus - 1)));
103 }
104 #endif	/* TRAPTRACE */
105 
106 /*
107  * common slave cpu initialization code
108  */
109 void
110 common_startup_init(cpu_t *cp, int cpuid)
111 {
112 	kthread_id_t tp;
113 	sfmmu_t *sfmmup;
114 	caddr_t	sp;
115 
116 	/*
117 	 * Allocate and initialize the startup thread for this CPU.
118 	 */
119 	tp = thread_create(NULL, 0, slave_startup, NULL, 0, &p0,
120 	    TS_STOPPED, maxclsyspri);
121 
122 	/*
123 	 * Set state to TS_ONPROC since this thread will start running
124 	 * as soon as the CPU comes online.
125 	 *
126 	 * All the other fields of the thread structure are setup by
127 	 * thread_create().
128 	 */
129 	THREAD_ONPROC(tp, cp);
130 	tp->t_preempt = 1;
131 	tp->t_bound_cpu = cp;
132 	tp->t_affinitycnt = 1;
133 	tp->t_cpu = cp;
134 	tp->t_disp_queue = cp->cpu_disp;
135 
136 	sfmmup = astosfmmu(&kas);
137 	CPUSET_ADD(sfmmup->sfmmu_cpusran, cpuid);
138 
139 	/*
140 	 * Setup thread to start in slave_startup.
141 	 */
142 	sp = tp->t_stk;
143 	tp->t_pc = (uintptr_t)slave_startup - 8;
144 	tp->t_sp = (uintptr_t)((struct rwindow *)sp - 1) - STACK_BIAS;
145 
146 	cp->cpu_id = cpuid;
147 	cp->cpu_self = cp;
148 	cp->cpu_thread = tp;
149 	cp->cpu_lwp = NULL;
150 	cp->cpu_dispthread = tp;
151 	cp->cpu_dispatch_pri = DISP_PRIO(tp);
152 	cp->cpu_startup_thread = tp;
153 }
154 
155 /*
156  * parametric flag setting functions.  these routines set the cpu
157  * state just prior to releasing the slave cpu.
158  */
159 void
160 cold_flag_set(int cpuid)
161 {
162 	cpu_t *cp;
163 
164 	ASSERT(MUTEX_HELD(&cpu_lock));
165 
166 	cp = cpu[cpuid];
167 	cp->cpu_flags |= CPU_RUNNING | CPU_ENABLE | CPU_EXISTS;
168 	cpu_add_active(cp);
169 	/*
170 	 * Add CPU_READY after the cpu_add_active() call
171 	 * to avoid pausing cp.
172 	 */
173 	cp->cpu_flags |= CPU_READY;		/* ready */
174 	cpu_set_state(cp);
175 }
176 
177 static void
178 warm_flag_set(int cpuid)
179 {
180 	cpu_t *cp;
181 
182 	ASSERT(MUTEX_HELD(&cpu_lock));
183 
184 	/*
185 	 * warm start activates cpus into the OFFLINE state
186 	 */
187 	cp = cpu[cpuid];
188 	cp->cpu_flags |= CPU_RUNNING | CPU_READY | CPU_EXISTS
189 	    | CPU_OFFLINE | CPU_QUIESCED;
190 	cpu_set_state(cp);
191 }
192 
193 /*
194  * Internal cpu startup sequencer
195  * The sequence is as follows:
196  *
197  * MASTER	SLAVE
198  * -------	----------
199  * assume the kernel data is initialized
200  * clear the proxy bit
201  * start the slave cpu
202  * wait for the slave cpu to set the proxy
203  *
204  *		the slave runs slave_startup and then sets the proxy
205  *		the slave waits for the master to add slave to the ready set
206  *
207  * the master finishes the initialization and
208  * adds the slave to the ready set
209  *
210  *		the slave exits the startup thread and is running
211  */
212 void
213 start_cpu(int cpuid, void(*flag_func)(int))
214 {
215 	extern void cpu_startup(int);
216 	int timout;
217 
218 	ASSERT(MUTEX_HELD(&cpu_lock));
219 
220 	/*
221 	 * Before we begin the dance, tell DTrace that we're about to start
222 	 * a CPU.
223 	 */
224 	if (dtrace_cpustart_init != NULL)
225 		(*dtrace_cpustart_init)();
226 
227 	/* start the slave cpu */
228 	CPUSET_DEL(proxy_ready_set, cpuid);
229 	if (prom_test("SUNW,start-cpu-by-cpuid") == 0) {
230 		(void) prom_startcpu_bycpuid(cpuid, (caddr_t)&cpu_startup,
231 		    cpuid);
232 	} else {
233 		/* "by-cpuid" interface didn't exist.  Do it the old way */
234 		pnode_t nodeid = cpunodes[cpuid].nodeid;
235 
236 		ASSERT(nodeid != (pnode_t)0);
237 		(void) prom_startcpu(nodeid, (caddr_t)&cpu_startup, cpuid);
238 	}
239 
240 	/* wait for the slave cpu to check in. */
241 	for (timout = CPU_WAKEUP_GRACE_MSEC; timout; timout--) {
242 		if (CPU_IN_SET(proxy_ready_set, cpuid))
243 			break;
244 		DELAY(1000);
245 	}
246 	if (timout == 0) {
247 		panic("cpu%d failed to start (2)", cpuid);
248 	}
249 
250 	/*
251 	 * The slave has started; we can tell DTrace that it's safe again.
252 	 */
253 	if (dtrace_cpustart_fini != NULL)
254 		(*dtrace_cpustart_fini)();
255 
256 	/* run the master side of stick synchronization for the slave cpu */
257 	sticksync_master();
258 
259 	/*
260 	 * deal with the cpu flags in a phase-specific manner
261 	 * for various reasons, this needs to run after the slave
262 	 * is checked in but before the slave is released.
263 	 */
264 	(*flag_func)(cpuid);
265 
266 	/* release the slave */
267 	CPUSET_ADD(cpu_ready_set, cpuid);
268 }
269 
270 #ifdef TRAPTRACE
271 int trap_tr0_inuse = 1;	/* it is always used on the boot cpu */
272 int trap_trace_inuse[NCPU];
273 #endif /* TRAPTRACE */
274 
275 #define	cpu_next_free	cpu_prev
276 
277 /*
278  * Routine to set up a CPU to prepare for starting it up.
279  */
280 int
281 setup_cpu_common(int cpuid)
282 {
283 	struct cpu *cp = NULL;
284 	kthread_id_t tp;
285 #ifdef TRAPTRACE
286 	int tt_index;
287 	TRAP_TRACE_CTL	*ctlp;
288 	caddr_t	newbuf;
289 #endif /* TRAPTRACE */
290 
291 	extern void idle();
292 	int	rval;
293 
294 	ASSERT(MUTEX_HELD(&cpu_lock));
295 	ASSERT(cpu[cpuid] == NULL);
296 
297 	ASSERT(ncpus <= max_ncpus);
298 
299 #ifdef TRAPTRACE
300 	/*
301 	 * allocate a traptrace buffer for this CPU.
302 	 */
303 	ctlp = &trap_trace_ctl[cpuid];
304 	if (!trap_tr0_inuse) {
305 		trap_tr0_inuse = 1;
306 		newbuf = trap_tr0;
307 		tt_index = -1;
308 	} else {
309 		for (tt_index = 0; tt_index < (max_ncpus-1); tt_index++)
310 			if (!trap_trace_inuse[tt_index])
311 				break;
312 		ASSERT(tt_index < max_ncpus - 1);
313 		trap_trace_inuse[tt_index] = 1;
314 		newbuf = (caddr_t)(ttrace_buf + (tt_index * TRAP_TSIZE));
315 	}
316 	ctlp->d.vaddr_base = newbuf;
317 	ctlp->d.offset = ctlp->d.last_offset = 0;
318 	ctlp->d.limit = trap_trace_bufsize;
319 	ctlp->d.paddr_base = va_to_pa(newbuf);
320 	ASSERT(ctlp->d.paddr_base != (uint64_t)-1);
321 #endif /* TRAPTRACE */
322 	/*
323 	 * initialize hv traptrace buffer for this CPU
324 	 */
325 	mach_htraptrace_setup(cpuid);
326 
327 	/*
328 	 * Obtain pointer to the appropriate cpu structure.
329 	 */
330 	if (cpu0.cpu_flags == 0) {
331 		cp = &cpu0;
332 	} else {
333 		/*
334 		 *  When dynamically allocating cpu structs,
335 		 *  cpus is used as a pointer to a list of freed
336 		 *  cpu structs.
337 		 */
338 		if (cpus) {
339 			/* grab the first cpu struct on the free list */
340 			cp = cpus;
341 			if (cp->cpu_next_free)
342 				cpus = cp->cpu_next_free;
343 			else
344 				cpus = NULL;
345 		}
346 	}
347 
348 	if (cp == NULL)
349 		cp = vmem_xalloc(static_alloc_arena, CPU_ALLOC_SIZE,
350 		    CPU_ALLOC_SIZE, 0, 0, NULL, NULL, VM_SLEEP);
351 
352 	bzero(cp, sizeof (*cp));
353 
354 	cp->cpu_id = cpuid;
355 	cp->cpu_self = cp;
356 
357 	/*
358 	 * Initialize ptl1_panic stack
359 	 */
360 	ptl1_init_cpu(cp);
361 
362 	/*
363 	 * Initialize the dispatcher for this CPU.
364 	 */
365 	disp_cpu_init(cp);
366 
367 	cpu_vm_data_init(cp);
368 
369 	/*
370 	 * Now, initialize per-CPU idle thread for this CPU.
371 	 */
372 	tp = thread_create(NULL, 0, idle, NULL, 0, &p0, TS_ONPROC, -1);
373 
374 	cp->cpu_idle_thread = tp;
375 
376 	tp->t_preempt = 1;
377 	tp->t_bound_cpu = cp;
378 	tp->t_affinitycnt = 1;
379 	tp->t_cpu = cp;
380 	tp->t_disp_queue = cp->cpu_disp;
381 
382 	/*
383 	 * Registering a thread in the callback table is usually
384 	 * done in the initialization code of the thread. In this
385 	 * case, we do it right after thread creation to avoid
386 	 * blocking idle thread while registering itself. It also
387 	 * avoids the possibility of reregistration in case a CPU
388 	 * restarts its idle thread.
389 	 */
390 	CALLB_CPR_INIT_SAFE(tp, "idle");
391 
392 	init_cpu_info(cp);
393 
394 	/*
395 	 * Initialize the interrupt threads for this CPU
396 	 */
397 	cpu_intr_alloc(cp, NINTR_THREADS);
398 
399 	/*
400 	 * Add CPU to list of available CPUs.
401 	 * It'll be on the active list after it is started.
402 	 */
403 	cpu_add_unit(cp);
404 
405 	/*
406 	 * Allocate and init cpu module private data structures,
407 	 * including scrubber.
408 	 */
409 	cpu_init_private(cp);
410 
411 	/*
412 	 * Initialize the CPUs physical ID cache, and processor groups
413 	 */
414 	pghw_physid_create(cp);
415 	pg_cpu_init(cp);
416 
417 	if ((rval = cpu_intrq_setup(cp)) != 0) {
418 		return (rval);
419 	}
420 
421 	/*
422 	 * Initialize MMU context domain information.
423 	 */
424 	sfmmu_cpu_init(cp);
425 
426 	return (0);
427 }
428 
429 /*
430  * Routine to clean up a CPU after shutting it down.
431  */
432 int
433 cleanup_cpu_common(int cpuid)
434 {
435 	struct cpu *cp;
436 #ifdef TRAPTRACE
437 	int i;
438 	TRAP_TRACE_CTL	*ctlp;
439 	caddr_t	newbuf;
440 #endif /* TRAPTRACE */
441 
442 	ASSERT(MUTEX_HELD(&cpu_lock));
443 	ASSERT(cpu[cpuid] != NULL);
444 
445 	cp = cpu[cpuid];
446 
447 	/* Free cpu module private data structures, including scrubber. */
448 	cpu_uninit_private(cp);
449 
450 	/* Free cpu ID string and brand string. */
451 	if (cp->cpu_idstr)
452 		kmem_free(cp->cpu_idstr, strlen(cp->cpu_idstr) + 1);
453 	if (cp->cpu_brandstr)
454 		kmem_free(cp->cpu_brandstr, strlen(cp->cpu_brandstr) + 1);
455 
456 	cpu_vm_data_destroy(cp);
457 
458 	/*
459 	 * Remove CPU from list of available CPUs.
460 	 */
461 	cpu_del_unit(cpuid);
462 
463 	/*
464 	 * Clean any machine specific interrupt states.
465 	 */
466 	cpu_intrq_cleanup(cp);
467 
468 	/*
469 	 * At this point, the only threads bound to this CPU should be
470 	 * special per-cpu threads: it's idle thread, it's pause thread,
471 	 * and it's interrupt threads.  Clean these up.
472 	 */
473 	cpu_destroy_bound_threads(cp);
474 
475 	/*
476 	 * Free the interrupt stack.
477 	 */
478 	segkp_release(segkp, cp->cpu_intr_stack);
479 
480 	/*
481 	 * Free hv traptrace buffer for this CPU.
482 	 */
483 	mach_htraptrace_cleanup(cpuid);
484 #ifdef TRAPTRACE
485 	/*
486 	 * Free the traptrace buffer for this CPU.
487 	 */
488 	ctlp = &trap_trace_ctl[cpuid];
489 	newbuf = ctlp->d.vaddr_base;
490 	i = (newbuf - ttrace_buf) / (TRAP_TSIZE);
491 	if (((newbuf - ttrace_buf) % (TRAP_TSIZE) == 0) &&
492 	    ((i >= 0) && (i < (max_ncpus-1)))) {
493 		/*
494 		 * This CPU got it's trap trace buffer from the
495 		 * boot-alloc'd bunch of them.
496 		 */
497 		trap_trace_inuse[i] = 0;
498 		bzero(newbuf, (TRAP_TSIZE));
499 	} else if (newbuf == trap_tr0) {
500 		trap_tr0_inuse = 0;
501 		bzero(trap_tr0, (TRAP_TSIZE));
502 	} else {
503 		cmn_err(CE_WARN, "failed to free trap trace buffer from cpu%d",
504 		    cpuid);
505 	}
506 	bzero(ctlp, sizeof (*ctlp));
507 #endif /* TRAPTRACE */
508 
509 	/*
510 	 * There is a race condition with mutex_vector_enter() which
511 	 * caches a cpu pointer. The race is detected by checking cpu_next.
512 	 */
513 	disp_cpu_fini(cp);
514 	cpu_pa[cpuid] = 0;
515 	if (CPU_MMU_CTXP(cp))
516 		sfmmu_cpu_cleanup(cp);
517 	bzero(cp, sizeof (*cp));
518 
519 	/*
520 	 * Place the freed cpu structure on the list of freed cpus.
521 	 */
522 	if (cp != &cpu0) {
523 		if (cpus) {
524 			cp->cpu_next_free = cpus;
525 			cpus = cp;
526 		}
527 		else
528 			cpus = cp;
529 	}
530 
531 	return (0);
532 }
533 
534 /*
535  * This routine is used to start a previously powered off processor.
536  * Note that restarted cpus are initialized into the offline state.
537  */
538 void
539 restart_other_cpu(int cpuid)
540 {
541 	struct cpu *cp;
542 	kthread_id_t tp;
543 	caddr_t	sp;
544 	extern void idle();
545 
546 	ASSERT(MUTEX_HELD(&cpu_lock));
547 	ASSERT(cpuid < NCPU && cpu[cpuid] != NULL);
548 
549 	/*
550 	 * Obtain pointer to the appropriate cpu structure.
551 	 */
552 	cp = cpu[cpuid];
553 
554 	common_startup_init(cp, cpuid);
555 
556 	/*
557 	 * idle thread t_lock is held when the idle thread is suspended.
558 	 * Manually unlock the t_lock of idle loop so that we can resume
559 	 * the suspended idle thread.
560 	 * Also adjust the PC of idle thread for re-retry.
561 	 */
562 	cp->cpu_intr_actv = 0;	/* clear the value from previous life */
563 	cp->cpu_m.mutex_ready = 0; /* we are not ready yet */
564 	lock_clear(&cp->cpu_idle_thread->t_lock);
565 	tp = cp->cpu_idle_thread;
566 
567 	sp = tp->t_stk;
568 	tp->t_sp = (uintptr_t)((struct rwindow *)sp - 1) - STACK_BIAS;
569 	tp->t_pc = (uintptr_t)idle - 8;
570 
571 	/*
572 	 * restart the cpu now
573 	 */
574 	promsafe_pause_cpus();
575 	start_cpu(cpuid, warm_flag_set);
576 	start_cpus();
577 
578 	/* call cmn_err outside pause_cpus/start_cpus to avoid deadlock */
579 	cmn_err(CE_CONT, "!cpu%d initialization complete - restarted\n",
580 	    cpuid);
581 }
582 
583 /*
584  * Startup function executed on 'other' CPUs.  This is the first
585  * C function after cpu_start sets up the cpu registers.
586  */
587 static void
588 slave_startup(void)
589 {
590 	struct cpu	*cp = CPU;
591 	ushort_t	original_flags = cp->cpu_flags;
592 
593 	mach_htraptrace_configure(cp->cpu_id);
594 	cpu_intrq_register(CPU);
595 	cp->cpu_m.mutex_ready = 1;
596 	cp->cpu_m.poke_cpu_outstanding = B_FALSE;
597 
598 	/* acknowledge that we are done with initialization */
599 	CPUSET_ADD(proxy_ready_set, cp->cpu_id);
600 
601 	/* synchronize STICK */
602 	sticksync_slave();
603 
604 	if (boothowto & RB_DEBUG)
605 		kdi_dvec_cpu_init(cp);
606 
607 	/*
608 	 * the slave will wait here forever -- assuming that the master
609 	 * will get back to us.  if it doesn't we've got bigger problems
610 	 * than a master not replying to this slave.
611 	 * the small delay improves the slave's responsiveness to the
612 	 * master's ack and decreases the time window between master and
613 	 * slave operations.
614 	 */
615 	while (!CPU_IN_SET(cpu_ready_set, cp->cpu_id))
616 		DELAY(1);
617 
618 	/* enable interrupts */
619 	(void) spl0();
620 
621 	/*
622 	 * Signature block update to indicate that this CPU is in OS now.
623 	 * This needs to be done after the PIL is lowered since on
624 	 * some platforms the update code may block.
625 	 */
626 	CPU_SIGNATURE(OS_SIG, SIGST_RUN, SIGSUBST_NULL, cp->cpu_id);
627 
628 	/*
629 	 * park the slave thread in a safe/quiet state and wait for the master
630 	 * to finish configuring this CPU before proceeding to thread_exit().
631 	 */
632 	while (((volatile ushort_t)cp->cpu_flags) & CPU_QUIESCED)
633 		DELAY(1);
634 
635 	/*
636 	 * Initialize CPC CPU state.
637 	 */
638 	kcpc_hw_startup_cpu(original_flags);
639 
640 	/*
641 	 * Notify the PG subsystem that the CPU  has started
642 	 */
643 	pg_cmt_cpu_startup(CPU);
644 
645 	/*
646 	 * Now we are done with the startup thread, so free it up.
647 	 */
648 	thread_exit();
649 	cmn_err(CE_PANIC, "slave_startup: cannot return");
650 	/*NOTREACHED*/
651 }
652 
653 extern struct cpu	*cpu[NCPU];	/* pointers to all CPUs */
654 
655 /*
656  * cpu_bringup_set is a tunable (via /etc/system, debugger, etc.) that
657  * can be used during debugging to control which processors are brought
658  * online at boot time.  The variable represents a bitmap of the id's
659  * of the processors that will be brought online.  The initialization
660  * of this variable depends on the type of cpuset_t, which varies
661  * depending on the number of processors supported (see cpuvar.h).
662  */
663 cpuset_t cpu_bringup_set;
664 
665 
666 /*
667  * Generic start-all cpus entry.  Typically used during cold initialization.
668  * Note that cold start cpus are initialized into the online state.
669  */
670 /*ARGSUSED*/
671 void
672 start_other_cpus(int flag)
673 {
674 	int cpuid;
675 	extern void idlestop_init(void);
676 	int bootcpu;
677 
678 	/*
679 	 * Check if cpu_bringup_set has been explicitly set before
680 	 * initializing it.
681 	 */
682 	if (CPUSET_ISNULL(cpu_bringup_set)) {
683 #ifdef MPSAS
684 		/* just CPU 0 */
685 		CPUSET_ADD(cpu_bringup_set, 0);
686 #else
687 		CPUSET_ALL(cpu_bringup_set);
688 #endif
689 	}
690 
691 	if (&cpu_feature_init)
692 		cpu_feature_init();
693 
694 	/*
695 	 * Initialize CPC.
696 	 */
697 	kcpc_hw_init();
698 
699 	mutex_enter(&cpu_lock);
700 
701 	/*
702 	 * Initialize our own cpu_info.
703 	 */
704 	init_cpu_info(CPU);
705 
706 	/*
707 	 * Initialize CPU 0 cpu module private data area, including scrubber.
708 	 */
709 	cpu_init_private(CPU);
710 
711 	/*
712 	 * perform such initialization as is needed
713 	 * to be able to take CPUs on- and off-line.
714 	 */
715 	cpu_pause_init();
716 	xc_init();		/* initialize processor crosscalls */
717 	idlestop_init();
718 
719 	if (!use_mp) {
720 		mutex_exit(&cpu_lock);
721 		cmn_err(CE_CONT, "?***** Not in MP mode\n");
722 		return;
723 	}
724 	/*
725 	 * should we be initializing this cpu?
726 	 */
727 	bootcpu = getprocessorid();
728 
729 	/*
730 	 * launch all the slave cpus now
731 	 */
732 	for (cpuid = 0; cpuid < NCPU; cpuid++) {
733 		pnode_t nodeid = cpunodes[cpuid].nodeid;
734 
735 		if (nodeid == (pnode_t)0)
736 			continue;
737 
738 		if (cpuid == bootcpu) {
739 			if (!CPU_IN_SET(cpu_bringup_set, cpuid)) {
740 				cmn_err(CE_WARN, "boot cpu not a member "
741 				    "of cpu_bringup_set, adding it");
742 				CPUSET_ADD(cpu_bringup_set, cpuid);
743 			}
744 			continue;
745 		}
746 		if (!CPU_IN_SET(cpu_bringup_set, cpuid))
747 			continue;
748 
749 		ASSERT(cpu[cpuid] == NULL);
750 
751 		if (setup_cpu_common(cpuid)) {
752 			cmn_err(CE_PANIC, "cpu%d: setup failed", cpuid);
753 		}
754 
755 		common_startup_init(cpu[cpuid], cpuid);
756 
757 		start_cpu(cpuid, cold_flag_set);
758 		/*
759 		 * Because slave_startup() gets fired off after init()
760 		 * starts, we can't use the '?' trick to do 'boot -v'
761 		 * printing - so we always direct the 'cpu .. online'
762 		 * messages to the log.
763 		 */
764 		cmn_err(CE_CONT, "!cpu%d initialization complete - online\n",
765 		    cpuid);
766 
767 		/*
768 		 * XXX: register_cpu_setup() callbacks should be called here
769 		 * with a new setup code, CPU_BOOT (or something).
770 		 */
771 		if (dtrace_cpu_init != NULL)
772 			(*dtrace_cpu_init)(cpuid);
773 	}
774 
775 	/*
776 	 * since all the cpus are online now, redistribute interrupts to them.
777 	 */
778 	intr_redist_all_cpus();
779 
780 	mutex_exit(&cpu_lock);
781 
782 	/*
783 	 * Start the Ecache scrubber.  Must be done after all calls to
784 	 * cpu_init_private for every cpu (including CPU 0).
785 	 */
786 	cpu_init_cache_scrub();
787 
788 	if (&cpu_mp_init)
789 		cpu_mp_init();
790 }
791