xref: /illumos-gate/usr/src/uts/i86pc/os/mp_startup.c (revision 4d9fdb46)
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 (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 /*
26  * Copyright (c) 2010, Intel Corporation.
27  * All rights reserved.
28  */
29 /*
30  * Copyright 2020 Joyent, Inc.
31  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
32  * Copyright 2018 OmniOS Community Edition (OmniOSce) Association.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/thread.h>
37 #include <sys/cpuvar.h>
38 #include <sys/cpu.h>
39 #include <sys/t_lock.h>
40 #include <sys/param.h>
41 #include <sys/proc.h>
42 #include <sys/disp.h>
43 #include <sys/class.h>
44 #include <sys/cmn_err.h>
45 #include <sys/debug.h>
46 #include <sys/note.h>
47 #include <sys/asm_linkage.h>
48 #include <sys/x_call.h>
49 #include <sys/systm.h>
50 #include <sys/var.h>
51 #include <sys/vtrace.h>
52 #include <vm/hat.h>
53 #include <vm/as.h>
54 #include <vm/seg_kmem.h>
55 #include <vm/seg_kp.h>
56 #include <sys/segments.h>
57 #include <sys/kmem.h>
58 #include <sys/stack.h>
59 #include <sys/smp_impldefs.h>
60 #include <sys/x86_archext.h>
61 #include <sys/machsystm.h>
62 #include <sys/traptrace.h>
63 #include <sys/clock.h>
64 #include <sys/cpc_impl.h>
65 #include <sys/pg.h>
66 #include <sys/cmt.h>
67 #include <sys/dtrace.h>
68 #include <sys/archsystm.h>
69 #include <sys/fp.h>
70 #include <sys/reboot.h>
71 #include <sys/kdi_machimpl.h>
72 #include <vm/hat_i86.h>
73 #include <vm/vm_dep.h>
74 #include <sys/memnode.h>
75 #include <sys/pci_cfgspace.h>
76 #include <sys/mach_mmu.h>
77 #include <sys/sysmacros.h>
78 #if defined(__xpv)
79 #include <sys/hypervisor.h>
80 #else
81 #include <sys/hma.h>
82 #endif
83 #include <sys/cpu_module.h>
84 #include <sys/ontrap.h>
85 
86 struct cpu	cpus[1] __aligned(MMU_PAGESIZE);
87 struct cpu	*cpu[NCPU] = {&cpus[0]};
88 struct cpu	*cpu_free_list;
89 cpu_core_t	cpu_core[NCPU];
90 
91 #define	cpu_next_free	cpu_prev
92 
93 /*
94  * Useful for disabling MP bring-up on a MP capable system.
95  */
96 int use_mp = 1;
97 
98 /*
99  * to be set by a PSM to indicate what cpus
100  * are sitting around on the system.
101  */
102 cpuset_t mp_cpus;
103 
104 /*
105  * This variable is used by the hat layer to decide whether or not
106  * critical sections are needed to prevent race conditions.  For sun4m,
107  * this variable is set once enough MP initialization has been done in
108  * order to allow cross calls.
109  */
110 int flushes_require_xcalls;
111 
112 cpuset_t cpu_ready_set;		/* initialized in startup() */
113 
114 static void mp_startup_boot(void);
115 static void mp_startup_hotplug(void);
116 
117 static void cpu_sep_enable(void);
118 static void cpu_sep_disable(void);
119 static void cpu_asysc_enable(void);
120 static void cpu_asysc_disable(void);
121 
122 /*
123  * Init CPU info - get CPU type info for processor_info system call.
124  */
125 void
126 init_cpu_info(struct cpu *cp)
127 {
128 	processor_info_t *pi = &cp->cpu_type_info;
129 
130 	/*
131 	 * Get clock-frequency property for the CPU.
132 	 */
133 	pi->pi_clock = cpu_freq;
134 
135 	/*
136 	 * Current frequency in Hz.
137 	 */
138 	cp->cpu_curr_clock = cpu_freq_hz;
139 
140 	/*
141 	 * Supported frequencies.
142 	 */
143 	if (cp->cpu_supp_freqs == NULL) {
144 		cpu_set_supp_freqs(cp, NULL);
145 	}
146 
147 	(void) strcpy(pi->pi_processor_type, "i386");
148 	if (fpu_exists)
149 		(void) strcpy(pi->pi_fputypes, "i387 compatible");
150 
151 	cp->cpu_idstr = kmem_zalloc(CPU_IDSTRLEN, KM_SLEEP);
152 	cp->cpu_brandstr = kmem_zalloc(CPU_IDSTRLEN, KM_SLEEP);
153 
154 	/*
155 	 * If called for the BSP, cp is equal to current CPU.
156 	 * For non-BSPs, cpuid info of cp is not ready yet, so use cpuid info
157 	 * of current CPU as default values for cpu_idstr and cpu_brandstr.
158 	 * They will be corrected in mp_startup_common() after cpuid_pass1()
159 	 * has been invoked on target CPU.
160 	 */
161 	(void) cpuid_getidstr(CPU, cp->cpu_idstr, CPU_IDSTRLEN);
162 	(void) cpuid_getbrandstr(CPU, cp->cpu_brandstr, CPU_IDSTRLEN);
163 }
164 
165 /*
166  * Configure syscall support on this CPU.
167  */
168 /*ARGSUSED*/
169 void
170 init_cpu_syscall(struct cpu *cp)
171 {
172 	kpreempt_disable();
173 
174 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
175 	    is_x86_feature(x86_featureset, X86FSET_ASYSC)) {
176 		uint64_t flags;
177 
178 #if !defined(__xpv)
179 		/*
180 		 * The syscall instruction imposes a certain ordering on
181 		 * segment selectors, so we double-check that ordering
182 		 * here.
183 		 */
184 		CTASSERT(KDS_SEL == KCS_SEL + 8);
185 		CTASSERT(UDS_SEL == U32CS_SEL + 8);
186 		CTASSERT(UCS_SEL == U32CS_SEL + 16);
187 #endif
188 
189 		/*
190 		 * Turn syscall/sysret extensions on.
191 		 */
192 		cpu_asysc_enable();
193 
194 		/*
195 		 * Program the magic registers ..
196 		 */
197 		wrmsr(MSR_AMD_STAR,
198 		    ((uint64_t)(U32CS_SEL << 16 | KCS_SEL)) << 32);
199 		if (kpti_enable == 1) {
200 			wrmsr(MSR_AMD_LSTAR,
201 			    (uint64_t)(uintptr_t)tr_sys_syscall);
202 			wrmsr(MSR_AMD_CSTAR,
203 			    (uint64_t)(uintptr_t)tr_sys_syscall32);
204 		} else {
205 			wrmsr(MSR_AMD_LSTAR,
206 			    (uint64_t)(uintptr_t)sys_syscall);
207 			wrmsr(MSR_AMD_CSTAR,
208 			    (uint64_t)(uintptr_t)sys_syscall32);
209 		}
210 
211 		/*
212 		 * This list of flags is masked off the incoming
213 		 * %rfl when we enter the kernel.
214 		 */
215 		flags = PS_IE | PS_T;
216 		if (is_x86_feature(x86_featureset, X86FSET_SMAP) == B_TRUE)
217 			flags |= PS_ACHK;
218 		wrmsr(MSR_AMD_SFMASK, flags);
219 	}
220 
221 	/*
222 	 * On 64-bit kernels on Nocona machines, the 32-bit syscall
223 	 * variant isn't available to 32-bit applications, but sysenter is.
224 	 */
225 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
226 	    is_x86_feature(x86_featureset, X86FSET_SEP)) {
227 
228 #if !defined(__xpv)
229 		/*
230 		 * The sysenter instruction imposes a certain ordering on
231 		 * segment selectors, so we double-check that ordering
232 		 * here. See "sysenter" in Intel document 245471-012, "IA-32
233 		 * Intel Architecture Software Developer's Manual Volume 2:
234 		 * Instruction Set Reference"
235 		 */
236 		CTASSERT(KDS_SEL == KCS_SEL + 8);
237 
238 		CTASSERT(U32CS_SEL == ((KCS_SEL + 16) | 3));
239 		CTASSERT(UDS_SEL == U32CS_SEL + 8);
240 #endif
241 
242 		cpu_sep_enable();
243 
244 		/*
245 		 * resume() sets this value to the base of the threads stack
246 		 * via a context handler.
247 		 */
248 		wrmsr(MSR_INTC_SEP_ESP, 0);
249 
250 		if (kpti_enable == 1) {
251 			wrmsr(MSR_INTC_SEP_EIP,
252 			    (uint64_t)(uintptr_t)tr_sys_sysenter);
253 		} else {
254 			wrmsr(MSR_INTC_SEP_EIP,
255 			    (uint64_t)(uintptr_t)sys_sysenter);
256 		}
257 	}
258 
259 	kpreempt_enable();
260 }
261 
262 #if !defined(__xpv)
263 /*
264  * Configure per-cpu ID GDT
265  */
266 static void
267 init_cpu_id_gdt(struct cpu *cp)
268 {
269 	/* Write cpu_id into limit field of GDT for usermode retrieval */
270 #if defined(__amd64)
271 	set_usegd(&cp->cpu_gdt[GDT_CPUID], SDP_SHORT, NULL, cp->cpu_id,
272 	    SDT_MEMRODA, SEL_UPL, SDP_BYTES, SDP_OP32);
273 #elif defined(__i386)
274 	set_usegd(&cp->cpu_gdt[GDT_CPUID], NULL, cp->cpu_id, SDT_MEMRODA,
275 	    SEL_UPL, SDP_BYTES, SDP_OP32);
276 #endif
277 }
278 #endif /* !defined(__xpv) */
279 
280 /*
281  * Multiprocessor initialization.
282  *
283  * Allocate and initialize the cpu structure, TRAPTRACE buffer, and the
284  * startup and idle threads for the specified CPU.
285  * Parameter boot is true for boot time operations and is false for CPU
286  * DR operations.
287  */
288 static struct cpu *
289 mp_cpu_configure_common(int cpun, boolean_t boot)
290 {
291 	struct cpu *cp;
292 	kthread_id_t tp;
293 	caddr_t	sp;
294 	proc_t *procp;
295 #if !defined(__xpv)
296 	extern int idle_cpu_prefer_mwait;
297 	extern void cpu_idle_mwait();
298 #endif
299 	extern void idle();
300 	extern void cpu_idle();
301 
302 #ifdef TRAPTRACE
303 	trap_trace_ctl_t *ttc = &trap_trace_ctl[cpun];
304 #endif
305 
306 	ASSERT(MUTEX_HELD(&cpu_lock));
307 	ASSERT(cpun < NCPU && cpu[cpun] == NULL);
308 
309 	if (cpu_free_list == NULL) {
310 		cp = kmem_zalloc(sizeof (*cp), KM_SLEEP);
311 	} else {
312 		cp = cpu_free_list;
313 		cpu_free_list = cp->cpu_next_free;
314 	}
315 
316 	cp->cpu_m.mcpu_istamp = cpun << 16;
317 
318 	/* Create per CPU specific threads in the process p0. */
319 	procp = &p0;
320 
321 	/*
322 	 * Initialize the dispatcher first.
323 	 */
324 	disp_cpu_init(cp);
325 
326 	cpu_vm_data_init(cp);
327 
328 	/*
329 	 * Allocate and initialize the startup thread for this CPU.
330 	 * Interrupt and process switch stacks get allocated later
331 	 * when the CPU starts running.
332 	 */
333 	tp = thread_create(NULL, 0, NULL, NULL, 0, procp,
334 	    TS_STOPPED, maxclsyspri);
335 
336 	/*
337 	 * Set state to TS_ONPROC since this thread will start running
338 	 * as soon as the CPU comes online.
339 	 *
340 	 * All the other fields of the thread structure are setup by
341 	 * thread_create().
342 	 */
343 	THREAD_ONPROC(tp, cp);
344 	tp->t_preempt = 1;
345 	tp->t_bound_cpu = cp;
346 	tp->t_affinitycnt = 1;
347 	tp->t_cpu = cp;
348 	tp->t_disp_queue = cp->cpu_disp;
349 
350 	/*
351 	 * Setup thread to start in mp_startup_common.
352 	 */
353 	sp = tp->t_stk;
354 	tp->t_sp = (uintptr_t)(sp - MINFRAME);
355 #if defined(__amd64)
356 	tp->t_sp -= STACK_ENTRY_ALIGN;		/* fake a call */
357 #endif
358 	/*
359 	 * Setup thread start entry point for boot or hotplug.
360 	 */
361 	if (boot) {
362 		tp->t_pc = (uintptr_t)mp_startup_boot;
363 	} else {
364 		tp->t_pc = (uintptr_t)mp_startup_hotplug;
365 	}
366 
367 	cp->cpu_id = cpun;
368 	cp->cpu_self = cp;
369 	cp->cpu_thread = tp;
370 	cp->cpu_lwp = NULL;
371 	cp->cpu_dispthread = tp;
372 	cp->cpu_dispatch_pri = DISP_PRIO(tp);
373 
374 	/*
375 	 * cpu_base_spl must be set explicitly here to prevent any blocking
376 	 * operations in mp_startup_common from causing the spl of the cpu
377 	 * to drop to 0 (allowing device interrupts before we're ready) in
378 	 * resume().
379 	 * cpu_base_spl MUST remain at LOCK_LEVEL until the cpu is CPU_READY.
380 	 * As an extra bit of security on DEBUG kernels, this is enforced with
381 	 * an assertion in mp_startup_common() -- before cpu_base_spl is set
382 	 * to its proper value.
383 	 */
384 	cp->cpu_base_spl = ipltospl(LOCK_LEVEL);
385 
386 	/*
387 	 * Now, initialize per-CPU idle thread for this CPU.
388 	 */
389 	tp = thread_create(NULL, PAGESIZE, idle, NULL, 0, procp, TS_ONPROC, -1);
390 
391 	cp->cpu_idle_thread = tp;
392 
393 	tp->t_preempt = 1;
394 	tp->t_bound_cpu = cp;
395 	tp->t_affinitycnt = 1;
396 	tp->t_cpu = cp;
397 	tp->t_disp_queue = cp->cpu_disp;
398 
399 	/*
400 	 * Bootstrap the CPU's PG data
401 	 */
402 	pg_cpu_bootstrap(cp);
403 
404 	/*
405 	 * Perform CPC initialization on the new CPU.
406 	 */
407 	kcpc_hw_init(cp);
408 
409 	/*
410 	 * Allocate virtual addresses for cpu_caddr1 and cpu_caddr2
411 	 * for each CPU.
412 	 */
413 	setup_vaddr_for_ppcopy(cp);
414 
415 	/*
416 	 * Allocate page for new GDT and initialize from current GDT.
417 	 */
418 #if !defined(__lint)
419 	ASSERT((sizeof (*cp->cpu_gdt) * NGDT) <= PAGESIZE);
420 #endif
421 	cp->cpu_gdt = kmem_zalloc(PAGESIZE, KM_SLEEP);
422 	bcopy(CPU->cpu_gdt, cp->cpu_gdt, (sizeof (*cp->cpu_gdt) * NGDT));
423 
424 #if defined(__i386)
425 	/*
426 	 * setup kernel %gs.
427 	 */
428 	set_usegd(&cp->cpu_gdt[GDT_GS], cp, sizeof (struct cpu) -1, SDT_MEMRWA,
429 	    SEL_KPL, 0, 1);
430 #endif
431 
432 	/*
433 	 * Allocate pages for the CPU LDT.
434 	 */
435 	cp->cpu_m.mcpu_ldt = kmem_zalloc(LDT_CPU_SIZE, KM_SLEEP);
436 	cp->cpu_m.mcpu_ldt_len = 0;
437 
438 	/*
439 	 * Allocate a per-CPU IDT and initialize the new IDT to the currently
440 	 * runing CPU.
441 	 */
442 #if !defined(__lint)
443 	ASSERT((sizeof (*CPU->cpu_idt) * NIDT) <= PAGESIZE);
444 #endif
445 	cp->cpu_idt = kmem_alloc(PAGESIZE, KM_SLEEP);
446 	bcopy(CPU->cpu_idt, cp->cpu_idt, PAGESIZE);
447 
448 	/*
449 	 * alloc space for cpuid info
450 	 */
451 	cpuid_alloc_space(cp);
452 #if !defined(__xpv)
453 	if (is_x86_feature(x86_featureset, X86FSET_MWAIT) &&
454 	    idle_cpu_prefer_mwait) {
455 		cp->cpu_m.mcpu_mwait = cpuid_mwait_alloc(cp);
456 		cp->cpu_m.mcpu_idle_cpu = cpu_idle_mwait;
457 	} else
458 #endif
459 		cp->cpu_m.mcpu_idle_cpu = cpu_idle;
460 
461 	init_cpu_info(cp);
462 
463 #if !defined(__xpv)
464 	init_cpu_id_gdt(cp);
465 #endif
466 
467 	/*
468 	 * alloc space for ucode_info
469 	 */
470 	ucode_alloc_space(cp);
471 	xc_init_cpu(cp);
472 	hat_cpu_online(cp);
473 
474 #ifdef TRAPTRACE
475 	/*
476 	 * If this is a TRAPTRACE kernel, allocate TRAPTRACE buffers
477 	 */
478 	ttc->ttc_first = (uintptr_t)kmem_zalloc(trap_trace_bufsize, KM_SLEEP);
479 	ttc->ttc_next = ttc->ttc_first;
480 	ttc->ttc_limit = ttc->ttc_first + trap_trace_bufsize;
481 #endif
482 
483 	/*
484 	 * Record that we have another CPU.
485 	 */
486 	/*
487 	 * Initialize the interrupt threads for this CPU
488 	 */
489 	cpu_intr_alloc(cp, NINTR_THREADS);
490 
491 	cp->cpu_flags = CPU_OFFLINE | CPU_QUIESCED | CPU_POWEROFF;
492 	cpu_set_state(cp);
493 
494 	/*
495 	 * Add CPU to list of available CPUs.  It'll be on the active list
496 	 * after mp_startup_common().
497 	 */
498 	cpu_add_unit(cp);
499 
500 	return (cp);
501 }
502 
503 /*
504  * Undo what was done in mp_cpu_configure_common
505  */
506 static void
507 mp_cpu_unconfigure_common(struct cpu *cp, int error)
508 {
509 	ASSERT(MUTEX_HELD(&cpu_lock));
510 
511 	/*
512 	 * Remove the CPU from the list of available CPUs.
513 	 */
514 	cpu_del_unit(cp->cpu_id);
515 
516 	if (error == ETIMEDOUT) {
517 		/*
518 		 * The cpu was started, but never *seemed* to run any
519 		 * code in the kernel; it's probably off spinning in its
520 		 * own private world, though with potential references to
521 		 * our kmem-allocated IDTs and GDTs (for example).
522 		 *
523 		 * Worse still, it may actually wake up some time later,
524 		 * so rather than guess what it might or might not do, we
525 		 * leave the fundamental data structures intact.
526 		 */
527 		cp->cpu_flags = 0;
528 		return;
529 	}
530 
531 	/*
532 	 * At this point, the only threads bound to this CPU should
533 	 * special per-cpu threads: it's idle thread, it's pause threads,
534 	 * and it's interrupt threads.  Clean these up.
535 	 */
536 	cpu_destroy_bound_threads(cp);
537 	cp->cpu_idle_thread = NULL;
538 
539 	/*
540 	 * Free the interrupt stack.
541 	 */
542 	segkp_release(segkp,
543 	    cp->cpu_intr_stack - (INTR_STACK_SIZE - SA(MINFRAME)));
544 	cp->cpu_intr_stack = NULL;
545 
546 #ifdef TRAPTRACE
547 	/*
548 	 * Discard the trap trace buffer
549 	 */
550 	{
551 		trap_trace_ctl_t *ttc = &trap_trace_ctl[cp->cpu_id];
552 
553 		kmem_free((void *)ttc->ttc_first, trap_trace_bufsize);
554 		ttc->ttc_first = (uintptr_t)NULL;
555 	}
556 #endif
557 
558 	hat_cpu_offline(cp);
559 
560 	ucode_free_space(cp);
561 
562 	/* Free CPU ID string and brand string. */
563 	if (cp->cpu_idstr) {
564 		kmem_free(cp->cpu_idstr, CPU_IDSTRLEN);
565 		cp->cpu_idstr = NULL;
566 	}
567 	if (cp->cpu_brandstr) {
568 		kmem_free(cp->cpu_brandstr, CPU_IDSTRLEN);
569 		cp->cpu_brandstr = NULL;
570 	}
571 
572 #if !defined(__xpv)
573 	if (cp->cpu_m.mcpu_mwait != NULL) {
574 		cpuid_mwait_free(cp);
575 		cp->cpu_m.mcpu_mwait = NULL;
576 	}
577 #endif
578 	cpuid_free_space(cp);
579 
580 	if (cp->cpu_idt != CPU->cpu_idt)
581 		kmem_free(cp->cpu_idt, PAGESIZE);
582 	cp->cpu_idt = NULL;
583 
584 	kmem_free(cp->cpu_m.mcpu_ldt, LDT_CPU_SIZE);
585 	cp->cpu_m.mcpu_ldt = NULL;
586 	cp->cpu_m.mcpu_ldt_len = 0;
587 
588 	kmem_free(cp->cpu_gdt, PAGESIZE);
589 	cp->cpu_gdt = NULL;
590 
591 	if (cp->cpu_supp_freqs != NULL) {
592 		size_t len = strlen(cp->cpu_supp_freqs) + 1;
593 		kmem_free(cp->cpu_supp_freqs, len);
594 		cp->cpu_supp_freqs = NULL;
595 	}
596 
597 	teardown_vaddr_for_ppcopy(cp);
598 
599 	kcpc_hw_fini(cp);
600 
601 	cp->cpu_dispthread = NULL;
602 	cp->cpu_thread = NULL;	/* discarded by cpu_destroy_bound_threads() */
603 
604 	cpu_vm_data_destroy(cp);
605 
606 	xc_fini_cpu(cp);
607 	disp_cpu_fini(cp);
608 
609 	ASSERT(cp != CPU0);
610 	bzero(cp, sizeof (*cp));
611 	cp->cpu_next_free = cpu_free_list;
612 	cpu_free_list = cp;
613 }
614 
615 /*
616  * Apply workarounds for known errata, and warn about those that are absent.
617  *
618  * System vendors occasionally create configurations which contain different
619  * revisions of the CPUs that are almost but not exactly the same.  At the
620  * time of writing, this meant that their clock rates were the same, their
621  * feature sets were the same, but the required workaround were -not-
622  * necessarily the same.  So, this routine is invoked on -every- CPU soon
623  * after starting to make sure that the resulting system contains the most
624  * pessimal set of workarounds needed to cope with *any* of the CPUs in the
625  * system.
626  *
627  * workaround_errata is invoked early in mlsetup() for CPU 0, and in
628  * mp_startup_common() for all slave CPUs. Slaves process workaround_errata
629  * prior to acknowledging their readiness to the master, so this routine will
630  * never be executed by multiple CPUs in parallel, thus making updates to
631  * global data safe.
632  *
633  * These workarounds are based on Rev 3.57 of the Revision Guide for
634  * AMD Athlon(tm) 64 and AMD Opteron(tm) Processors, August 2005.
635  */
636 
637 #if defined(OPTERON_ERRATUM_88)
638 int opteron_erratum_88;		/* if non-zero -> at least one cpu has it */
639 #endif
640 
641 #if defined(OPTERON_ERRATUM_91)
642 int opteron_erratum_91;		/* if non-zero -> at least one cpu has it */
643 #endif
644 
645 #if defined(OPTERON_ERRATUM_93)
646 int opteron_erratum_93;		/* if non-zero -> at least one cpu has it */
647 #endif
648 
649 #if defined(OPTERON_ERRATUM_95)
650 int opteron_erratum_95;		/* if non-zero -> at least one cpu has it */
651 #endif
652 
653 #if defined(OPTERON_ERRATUM_100)
654 int opteron_erratum_100;	/* if non-zero -> at least one cpu has it */
655 #endif
656 
657 #if defined(OPTERON_ERRATUM_108)
658 int opteron_erratum_108;	/* if non-zero -> at least one cpu has it */
659 #endif
660 
661 #if defined(OPTERON_ERRATUM_109)
662 int opteron_erratum_109;	/* if non-zero -> at least one cpu has it */
663 #endif
664 
665 #if defined(OPTERON_ERRATUM_121)
666 int opteron_erratum_121;	/* if non-zero -> at least one cpu has it */
667 #endif
668 
669 #if defined(OPTERON_ERRATUM_122)
670 int opteron_erratum_122;	/* if non-zero -> at least one cpu has it */
671 #endif
672 
673 #if defined(OPTERON_ERRATUM_123)
674 int opteron_erratum_123;	/* if non-zero -> at least one cpu has it */
675 #endif
676 
677 #if defined(OPTERON_ERRATUM_131)
678 int opteron_erratum_131;	/* if non-zero -> at least one cpu has it */
679 #endif
680 
681 #if defined(OPTERON_WORKAROUND_6336786)
682 int opteron_workaround_6336786;	/* non-zero -> WA relevant and applied */
683 int opteron_workaround_6336786_UP = 0;	/* Not needed for UP */
684 #endif
685 
686 #if defined(OPTERON_WORKAROUND_6323525)
687 int opteron_workaround_6323525;	/* if non-zero -> at least one cpu has it */
688 #endif
689 
690 #if defined(OPTERON_ERRATUM_298)
691 int opteron_erratum_298;
692 #endif
693 
694 #if defined(OPTERON_ERRATUM_721)
695 int opteron_erratum_721;
696 #endif
697 
698 static void
699 workaround_warning(cpu_t *cp, uint_t erratum)
700 {
701 	cmn_err(CE_WARN, "cpu%d: no workaround for erratum %u",
702 	    cp->cpu_id, erratum);
703 }
704 
705 static void
706 workaround_applied(uint_t erratum)
707 {
708 	if (erratum > 1000000)
709 		cmn_err(CE_CONT, "?workaround applied for cpu issue #%d\n",
710 		    erratum);
711 	else
712 		cmn_err(CE_CONT, "?workaround applied for cpu erratum #%d\n",
713 		    erratum);
714 }
715 
716 static void
717 msr_warning(cpu_t *cp, const char *rw, uint_t msr, int error)
718 {
719 	cmn_err(CE_WARN, "cpu%d: couldn't %smsr 0x%x, error %d",
720 	    cp->cpu_id, rw, msr, error);
721 }
722 
723 /*
724  * Determine the number of nodes in a Hammer / Greyhound / Griffin family
725  * system.
726  */
727 static uint_t
728 opteron_get_nnodes(void)
729 {
730 	static uint_t nnodes = 0;
731 
732 	if (nnodes == 0) {
733 #ifdef	DEBUG
734 		uint_t family;
735 
736 		/*
737 		 * This routine uses a PCI config space based mechanism
738 		 * for retrieving the number of nodes in the system.
739 		 * Device 24, function 0, offset 0x60 as used here is not
740 		 * AMD processor architectural, and may not work on processor
741 		 * families other than those listed below.
742 		 *
743 		 * Callers of this routine must ensure that we're running on
744 		 * a processor which supports this mechanism.
745 		 * The assertion below is meant to catch calls on unsupported
746 		 * processors.
747 		 */
748 		family = cpuid_getfamily(CPU);
749 		ASSERT(family == 0xf || family == 0x10 || family == 0x11);
750 #endif	/* DEBUG */
751 
752 		/*
753 		 * Obtain the number of nodes in the system from
754 		 * bits [6:4] of the Node ID register on node 0.
755 		 *
756 		 * The actual node count is NodeID[6:4] + 1
757 		 *
758 		 * The Node ID register is accessed via function 0,
759 		 * offset 0x60. Node 0 is device 24.
760 		 */
761 		nnodes = ((pci_getl_func(0, 24, 0, 0x60) & 0x70) >> 4) + 1;
762 	}
763 	return (nnodes);
764 }
765 
766 uint_t
767 do_erratum_298(struct cpu *cpu)
768 {
769 	static int	osvwrc = -3;
770 	extern int	osvw_opteron_erratum(cpu_t *, uint_t);
771 
772 	/*
773 	 * L2 Eviction May Occur During Processor Operation To Set
774 	 * Accessed or Dirty Bit.
775 	 */
776 	if (osvwrc == -3) {
777 		osvwrc = osvw_opteron_erratum(cpu, 298);
778 	} else {
779 		/* osvw return codes should be consistent for all cpus */
780 		ASSERT(osvwrc == osvw_opteron_erratum(cpu, 298));
781 	}
782 
783 	switch (osvwrc) {
784 	case 0:		/* erratum is not present: do nothing */
785 		break;
786 	case 1:		/* erratum is present: BIOS workaround applied */
787 		/*
788 		 * check if workaround is actually in place and issue warning
789 		 * if not.
790 		 */
791 		if (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
792 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0)) {
793 #if defined(OPTERON_ERRATUM_298)
794 			opteron_erratum_298++;
795 #else
796 			workaround_warning(cpu, 298);
797 			return (1);
798 #endif
799 		}
800 		break;
801 	case -1:	/* cannot determine via osvw: check cpuid */
802 		if ((cpuid_opteron_erratum(cpu, 298) > 0) &&
803 		    (((rdmsr(MSR_AMD_HWCR) & AMD_HWCR_TLBCACHEDIS) == 0) ||
804 		    ((rdmsr(MSR_AMD_BU_CFG) & AMD_BU_CFG_E298) == 0))) {
805 #if defined(OPTERON_ERRATUM_298)
806 			opteron_erratum_298++;
807 #else
808 			workaround_warning(cpu, 298);
809 			return (1);
810 #endif
811 		}
812 		break;
813 	}
814 	return (0);
815 }
816 
817 uint_t
818 workaround_errata(struct cpu *cpu)
819 {
820 	uint_t missing = 0;
821 
822 	ASSERT(cpu == CPU);
823 
824 	/*LINTED*/
825 	if (cpuid_opteron_erratum(cpu, 88) > 0) {
826 		/*
827 		 * SWAPGS May Fail To Read Correct GS Base
828 		 */
829 #if defined(OPTERON_ERRATUM_88)
830 		/*
831 		 * The workaround is an mfence in the relevant assembler code
832 		 */
833 		opteron_erratum_88++;
834 #else
835 		workaround_warning(cpu, 88);
836 		missing++;
837 #endif
838 	}
839 
840 	if (cpuid_opteron_erratum(cpu, 91) > 0) {
841 		/*
842 		 * Software Prefetches May Report A Page Fault
843 		 */
844 #if defined(OPTERON_ERRATUM_91)
845 		/*
846 		 * fix is in trap.c
847 		 */
848 		opteron_erratum_91++;
849 #else
850 		workaround_warning(cpu, 91);
851 		missing++;
852 #endif
853 	}
854 
855 	if (cpuid_opteron_erratum(cpu, 93) > 0) {
856 		/*
857 		 * RSM Auto-Halt Restart Returns to Incorrect RIP
858 		 */
859 #if defined(OPTERON_ERRATUM_93)
860 		/*
861 		 * fix is in trap.c
862 		 */
863 		opteron_erratum_93++;
864 #else
865 		workaround_warning(cpu, 93);
866 		missing++;
867 #endif
868 	}
869 
870 	/*LINTED*/
871 	if (cpuid_opteron_erratum(cpu, 95) > 0) {
872 		/*
873 		 * RET Instruction May Return to Incorrect EIP
874 		 */
875 #if defined(OPTERON_ERRATUM_95)
876 #if defined(_LP64)
877 		/*
878 		 * Workaround this by ensuring that 32-bit user code and
879 		 * 64-bit kernel code never occupy the same address
880 		 * range mod 4G.
881 		 */
882 		if (_userlimit32 > 0xc0000000ul)
883 			*(uintptr_t *)&_userlimit32 = 0xc0000000ul;
884 
885 		/*LINTED*/
886 		ASSERT((uint32_t)COREHEAP_BASE == 0xc0000000u);
887 		opteron_erratum_95++;
888 #endif	/* _LP64 */
889 #else
890 		workaround_warning(cpu, 95);
891 		missing++;
892 #endif
893 	}
894 
895 	if (cpuid_opteron_erratum(cpu, 100) > 0) {
896 		/*
897 		 * Compatibility Mode Branches Transfer to Illegal Address
898 		 */
899 #if defined(OPTERON_ERRATUM_100)
900 		/*
901 		 * fix is in trap.c
902 		 */
903 		opteron_erratum_100++;
904 #else
905 		workaround_warning(cpu, 100);
906 		missing++;
907 #endif
908 	}
909 
910 	/*LINTED*/
911 	if (cpuid_opteron_erratum(cpu, 108) > 0) {
912 		/*
913 		 * CPUID Instruction May Return Incorrect Model Number In
914 		 * Some Processors
915 		 */
916 #if defined(OPTERON_ERRATUM_108)
917 		/*
918 		 * (Our cpuid-handling code corrects the model number on
919 		 * those processors)
920 		 */
921 #else
922 		workaround_warning(cpu, 108);
923 		missing++;
924 #endif
925 	}
926 
927 	/*LINTED*/
928 	if (cpuid_opteron_erratum(cpu, 109) > 0) do {
929 		/*
930 		 * Certain Reverse REP MOVS May Produce Unpredictable Behavior
931 		 */
932 #if defined(OPTERON_ERRATUM_109)
933 		/*
934 		 * The "workaround" is to print a warning to upgrade the BIOS
935 		 */
936 		uint64_t value;
937 		const uint_t msr = MSR_AMD_PATCHLEVEL;
938 		int err;
939 
940 		if ((err = checked_rdmsr(msr, &value)) != 0) {
941 			msr_warning(cpu, "rd", msr, err);
942 			workaround_warning(cpu, 109);
943 			missing++;
944 		}
945 		if (value == 0)
946 			opteron_erratum_109++;
947 #else
948 		workaround_warning(cpu, 109);
949 		missing++;
950 #endif
951 	/*CONSTANTCONDITION*/
952 	} while (0);
953 
954 	/*LINTED*/
955 	if (cpuid_opteron_erratum(cpu, 121) > 0) {
956 		/*
957 		 * Sequential Execution Across Non_Canonical Boundary Caused
958 		 * Processor Hang
959 		 */
960 #if defined(OPTERON_ERRATUM_121)
961 #if defined(_LP64)
962 		/*
963 		 * Erratum 121 is only present in long (64 bit) mode.
964 		 * Workaround is to include the page immediately before the
965 		 * va hole to eliminate the possibility of system hangs due to
966 		 * sequential execution across the va hole boundary.
967 		 */
968 		if (opteron_erratum_121)
969 			opteron_erratum_121++;
970 		else {
971 			if (hole_start) {
972 				hole_start -= PAGESIZE;
973 			} else {
974 				/*
975 				 * hole_start not yet initialized by
976 				 * mmu_init. Initialize hole_start
977 				 * with value to be subtracted.
978 				 */
979 				hole_start = PAGESIZE;
980 			}
981 			opteron_erratum_121++;
982 		}
983 #endif	/* _LP64 */
984 #else
985 		workaround_warning(cpu, 121);
986 		missing++;
987 #endif
988 	}
989 
990 	/*LINTED*/
991 	if (cpuid_opteron_erratum(cpu, 122) > 0) do {
992 		/*
993 		 * TLB Flush Filter May Cause Coherency Problem in
994 		 * Multiprocessor Systems
995 		 */
996 #if defined(OPTERON_ERRATUM_122)
997 		uint64_t value;
998 		const uint_t msr = MSR_AMD_HWCR;
999 		int error;
1000 
1001 		/*
1002 		 * Erratum 122 is only present in MP configurations (multi-core
1003 		 * or multi-processor).
1004 		 */
1005 #if defined(__xpv)
1006 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
1007 			break;
1008 		if (!opteron_erratum_122 && xpv_nr_phys_cpus() == 1)
1009 			break;
1010 #else
1011 		if (!opteron_erratum_122 && opteron_get_nnodes() == 1 &&
1012 		    cpuid_get_ncpu_per_chip(cpu) == 1)
1013 			break;
1014 #endif
1015 		/* disable TLB Flush Filter */
1016 
1017 		if ((error = checked_rdmsr(msr, &value)) != 0) {
1018 			msr_warning(cpu, "rd", msr, error);
1019 			workaround_warning(cpu, 122);
1020 			missing++;
1021 		} else {
1022 			value |= (uint64_t)AMD_HWCR_FFDIS;
1023 			if ((error = checked_wrmsr(msr, value)) != 0) {
1024 				msr_warning(cpu, "wr", msr, error);
1025 				workaround_warning(cpu, 122);
1026 				missing++;
1027 			}
1028 		}
1029 		opteron_erratum_122++;
1030 #else
1031 		workaround_warning(cpu, 122);
1032 		missing++;
1033 #endif
1034 	/*CONSTANTCONDITION*/
1035 	} while (0);
1036 
1037 	/*LINTED*/
1038 	if (cpuid_opteron_erratum(cpu, 123) > 0) do {
1039 		/*
1040 		 * Bypassed Reads May Cause Data Corruption of System Hang in
1041 		 * Dual Core Processors
1042 		 */
1043 #if defined(OPTERON_ERRATUM_123)
1044 		uint64_t value;
1045 		const uint_t msr = MSR_AMD_PATCHLEVEL;
1046 		int err;
1047 
1048 		/*
1049 		 * Erratum 123 applies only to multi-core cpus.
1050 		 */
1051 		if (cpuid_get_ncpu_per_chip(cpu) < 2)
1052 			break;
1053 #if defined(__xpv)
1054 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
1055 			break;
1056 #endif
1057 		/*
1058 		 * The "workaround" is to print a warning to upgrade the BIOS
1059 		 */
1060 		if ((err = checked_rdmsr(msr, &value)) != 0) {
1061 			msr_warning(cpu, "rd", msr, err);
1062 			workaround_warning(cpu, 123);
1063 			missing++;
1064 		}
1065 		if (value == 0)
1066 			opteron_erratum_123++;
1067 #else
1068 		workaround_warning(cpu, 123);
1069 		missing++;
1070 
1071 #endif
1072 	/*CONSTANTCONDITION*/
1073 	} while (0);
1074 
1075 	/*LINTED*/
1076 	if (cpuid_opteron_erratum(cpu, 131) > 0) do {
1077 		/*
1078 		 * Multiprocessor Systems with Four or More Cores May Deadlock
1079 		 * Waiting for a Probe Response
1080 		 */
1081 #if defined(OPTERON_ERRATUM_131)
1082 		uint64_t nbcfg;
1083 		const uint_t msr = MSR_AMD_NB_CFG;
1084 		const uint64_t wabits =
1085 		    AMD_NB_CFG_SRQ_HEARTBEAT | AMD_NB_CFG_SRQ_SPR;
1086 		int error;
1087 
1088 		/*
1089 		 * Erratum 131 applies to any system with four or more cores.
1090 		 */
1091 		if (opteron_erratum_131)
1092 			break;
1093 #if defined(__xpv)
1094 		if (!DOMAIN_IS_INITDOMAIN(xen_info))
1095 			break;
1096 		if (xpv_nr_phys_cpus() < 4)
1097 			break;
1098 #else
1099 		if (opteron_get_nnodes() * cpuid_get_ncpu_per_chip(cpu) < 4)
1100 			break;
1101 #endif
1102 		/*
1103 		 * Print a warning if neither of the workarounds for
1104 		 * erratum 131 is present.
1105 		 */
1106 		if ((error = checked_rdmsr(msr, &nbcfg)) != 0) {
1107 			msr_warning(cpu, "rd", msr, error);
1108 			workaround_warning(cpu, 131);
1109 			missing++;
1110 		} else if ((nbcfg & wabits) == 0) {
1111 			opteron_erratum_131++;
1112 		} else {
1113 			/* cannot have both workarounds set */
1114 			ASSERT((nbcfg & wabits) != wabits);
1115 		}
1116 #else
1117 		workaround_warning(cpu, 131);
1118 		missing++;
1119 #endif
1120 	/*CONSTANTCONDITION*/
1121 	} while (0);
1122 
1123 	/*
1124 	 * This isn't really an erratum, but for convenience the
1125 	 * detection/workaround code lives here and in cpuid_opteron_erratum.
1126 	 * Note, the technique only is valid on families before 12h and
1127 	 * certainly doesn't work when we're virtualized. This is checked for in
1128 	 * the erratum workaround.
1129 	 */
1130 	if (cpuid_opteron_erratum(cpu, 6336786) > 0) {
1131 #if defined(OPTERON_WORKAROUND_6336786)
1132 		/*
1133 		 * Disable C1-Clock ramping on multi-core/multi-processor
1134 		 * K8 platforms to guard against TSC drift.
1135 		 */
1136 		if (opteron_workaround_6336786) {
1137 			opteron_workaround_6336786++;
1138 #if defined(__xpv)
1139 		} else if ((DOMAIN_IS_INITDOMAIN(xen_info) &&
1140 		    xpv_nr_phys_cpus() > 1) ||
1141 		    opteron_workaround_6336786_UP) {
1142 			/*
1143 			 * XXPV	Hmm.  We can't walk the Northbridges on
1144 			 *	the hypervisor; so just complain and drive
1145 			 *	on.  This probably needs to be fixed in
1146 			 *	the hypervisor itself.
1147 			 */
1148 			opteron_workaround_6336786++;
1149 			workaround_warning(cpu, 6336786);
1150 #else	/* __xpv */
1151 		} else if ((opteron_get_nnodes() *
1152 		    cpuid_get_ncpu_per_chip(cpu) > 1) ||
1153 		    opteron_workaround_6336786_UP) {
1154 
1155 			uint_t	node, nnodes;
1156 			uint8_t data;
1157 
1158 			nnodes = opteron_get_nnodes();
1159 			for (node = 0; node < nnodes; node++) {
1160 				/*
1161 				 * Clear PMM7[1:0] (function 3, offset 0x87)
1162 				 * Northbridge device is the node id + 24.
1163 				 */
1164 				data = pci_getb_func(0, node + 24, 3, 0x87);
1165 				data &= 0xFC;
1166 				pci_putb_func(0, node + 24, 3, 0x87, data);
1167 			}
1168 			opteron_workaround_6336786++;
1169 #endif	/* __xpv */
1170 		}
1171 #else
1172 		workaround_warning(cpu, 6336786);
1173 		missing++;
1174 #endif
1175 	}
1176 
1177 	/*LINTED*/
1178 	/*
1179 	 * Mutex primitives don't work as expected. This is erratum #147 from
1180 	 * 'Revision Guide for AMD Athlon 64 and AMD Opteron Processors'
1181 	 * document 25759.
1182 	 */
1183 	if (cpuid_opteron_erratum(cpu, 6323525) > 0) {
1184 #if defined(OPTERON_WORKAROUND_6323525)
1185 		/*
1186 		 * This problem only occurs with 2 or more cores. If bit in
1187 		 * MSR_AMD_BU_CFG set, then not applicable. The workaround
1188 		 * is to patch the semaphone routines with the lfence
1189 		 * instruction to provide necessary load memory barrier with
1190 		 * possible subsequent read-modify-write ops.
1191 		 *
1192 		 * It is too early in boot to call the patch routine so
1193 		 * set erratum variable to be done in startup_end().
1194 		 */
1195 		if (opteron_workaround_6323525) {
1196 			opteron_workaround_6323525++;
1197 #if defined(__xpv)
1198 		} else if (is_x86_feature(x86_featureset, X86FSET_SSE2)) {
1199 			if (DOMAIN_IS_INITDOMAIN(xen_info)) {
1200 				/*
1201 				 * XXPV	Use dom0_msr here when extended
1202 				 *	operations are supported?
1203 				 */
1204 				if (xpv_nr_phys_cpus() > 1)
1205 					opteron_workaround_6323525++;
1206 			} else {
1207 				/*
1208 				 * We have no way to tell how many physical
1209 				 * cpus there are, or even if this processor
1210 				 * has the problem, so enable the workaround
1211 				 * unconditionally (at some performance cost).
1212 				 */
1213 				opteron_workaround_6323525++;
1214 			}
1215 #else	/* __xpv */
1216 		} else if (is_x86_feature(x86_featureset, X86FSET_SSE2) &&
1217 		    ((opteron_get_nnodes() *
1218 		    cpuid_get_ncpu_per_chip(cpu)) > 1)) {
1219 			if ((xrdmsr(MSR_AMD_BU_CFG) & (UINT64_C(1) << 33)) == 0)
1220 				opteron_workaround_6323525++;
1221 #endif	/* __xpv */
1222 		}
1223 #else
1224 		workaround_warning(cpu, 6323525);
1225 		missing++;
1226 #endif
1227 	}
1228 
1229 	missing += do_erratum_298(cpu);
1230 
1231 	if (cpuid_opteron_erratum(cpu, 721) > 0) {
1232 #if defined(OPTERON_ERRATUM_721)
1233 		on_trap_data_t otd;
1234 
1235 		if (!on_trap(&otd, OT_DATA_ACCESS))
1236 			wrmsr(MSR_AMD_DE_CFG,
1237 			    rdmsr(MSR_AMD_DE_CFG) | AMD_DE_CFG_E721);
1238 		no_trap();
1239 
1240 		opteron_erratum_721++;
1241 #else
1242 		workaround_warning(cpu, 721);
1243 		missing++;
1244 #endif
1245 	}
1246 
1247 #ifdef __xpv
1248 	return (0);
1249 #else
1250 	return (missing);
1251 #endif
1252 }
1253 
1254 void
1255 workaround_errata_end()
1256 {
1257 #if defined(OPTERON_ERRATUM_88)
1258 	if (opteron_erratum_88)
1259 		workaround_applied(88);
1260 #endif
1261 #if defined(OPTERON_ERRATUM_91)
1262 	if (opteron_erratum_91)
1263 		workaround_applied(91);
1264 #endif
1265 #if defined(OPTERON_ERRATUM_93)
1266 	if (opteron_erratum_93)
1267 		workaround_applied(93);
1268 #endif
1269 #if defined(OPTERON_ERRATUM_95)
1270 	if (opteron_erratum_95)
1271 		workaround_applied(95);
1272 #endif
1273 #if defined(OPTERON_ERRATUM_100)
1274 	if (opteron_erratum_100)
1275 		workaround_applied(100);
1276 #endif
1277 #if defined(OPTERON_ERRATUM_108)
1278 	if (opteron_erratum_108)
1279 		workaround_applied(108);
1280 #endif
1281 #if defined(OPTERON_ERRATUM_109)
1282 	if (opteron_erratum_109) {
1283 		cmn_err(CE_WARN,
1284 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
1285 		    " processor\nerratum 109 was not detected; updating your"
1286 		    " system's BIOS to a version\ncontaining this"
1287 		    " microcode patch is HIGHLY recommended or erroneous"
1288 		    " system\noperation may occur.\n");
1289 	}
1290 #endif
1291 #if defined(OPTERON_ERRATUM_121)
1292 	if (opteron_erratum_121)
1293 		workaround_applied(121);
1294 #endif
1295 #if defined(OPTERON_ERRATUM_122)
1296 	if (opteron_erratum_122)
1297 		workaround_applied(122);
1298 #endif
1299 #if defined(OPTERON_ERRATUM_123)
1300 	if (opteron_erratum_123) {
1301 		cmn_err(CE_WARN,
1302 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
1303 		    " processor\nerratum 123 was not detected; updating your"
1304 		    " system's BIOS to a version\ncontaining this"
1305 		    " microcode patch is HIGHLY recommended or erroneous"
1306 		    " system\noperation may occur.\n");
1307 	}
1308 #endif
1309 #if defined(OPTERON_ERRATUM_131)
1310 	if (opteron_erratum_131) {
1311 		cmn_err(CE_WARN,
1312 		    "BIOS microcode patch for AMD Athlon(tm) 64/Opteron(tm)"
1313 		    " processor\nerratum 131 was not detected; updating your"
1314 		    " system's BIOS to a version\ncontaining this"
1315 		    " microcode patch is HIGHLY recommended or erroneous"
1316 		    " system\noperation may occur.\n");
1317 	}
1318 #endif
1319 #if defined(OPTERON_WORKAROUND_6336786)
1320 	if (opteron_workaround_6336786)
1321 		workaround_applied(6336786);
1322 #endif
1323 #if defined(OPTERON_WORKAROUND_6323525)
1324 	if (opteron_workaround_6323525)
1325 		workaround_applied(6323525);
1326 #endif
1327 #if defined(OPTERON_ERRATUM_298)
1328 	if (opteron_erratum_298) {
1329 		cmn_err(CE_WARN,
1330 		    "BIOS microcode patch for AMD 64/Opteron(tm)"
1331 		    " processor\nerratum 298 was not detected; updating your"
1332 		    " system's BIOS to a version\ncontaining this"
1333 		    " microcode patch is HIGHLY recommended or erroneous"
1334 		    " system\noperation may occur.\n");
1335 	}
1336 #endif
1337 #if defined(OPTERON_ERRATUM_721)
1338 	if (opteron_erratum_721)
1339 		workaround_applied(721);
1340 #endif
1341 }
1342 
1343 /*
1344  * The procset_slave and procset_master are used to synchronize
1345  * between the control CPU and the target CPU when starting CPUs.
1346  */
1347 static cpuset_t procset_slave, procset_master;
1348 
1349 static void
1350 mp_startup_wait(cpuset_t *sp, processorid_t cpuid)
1351 {
1352 	cpuset_t tempset;
1353 
1354 	for (tempset = *sp; !CPU_IN_SET(tempset, cpuid);
1355 	    tempset = *(volatile cpuset_t *)sp) {
1356 		SMT_PAUSE();
1357 	}
1358 	CPUSET_ATOMIC_DEL(*(cpuset_t *)sp, cpuid);
1359 }
1360 
1361 static void
1362 mp_startup_signal(cpuset_t *sp, processorid_t cpuid)
1363 {
1364 	cpuset_t tempset;
1365 
1366 	CPUSET_ATOMIC_ADD(*(cpuset_t *)sp, cpuid);
1367 	for (tempset = *sp; CPU_IN_SET(tempset, cpuid);
1368 	    tempset = *(volatile cpuset_t *)sp) {
1369 		SMT_PAUSE();
1370 	}
1371 }
1372 
1373 int
1374 mp_start_cpu_common(cpu_t *cp, boolean_t boot)
1375 {
1376 	_NOTE(ARGUNUSED(boot));
1377 
1378 	void *ctx;
1379 	int delays;
1380 	int error = 0;
1381 	cpuset_t tempset;
1382 	processorid_t cpuid;
1383 #ifndef __xpv
1384 	extern void cpupm_init(cpu_t *);
1385 #endif
1386 
1387 	ASSERT(cp != NULL);
1388 	cpuid = cp->cpu_id;
1389 	ctx = mach_cpucontext_alloc(cp);
1390 	if (ctx == NULL) {
1391 		cmn_err(CE_WARN,
1392 		    "cpu%d: failed to allocate context", cp->cpu_id);
1393 		return (EAGAIN);
1394 	}
1395 	error = mach_cpu_start(cp, ctx);
1396 	if (error != 0) {
1397 		cmn_err(CE_WARN,
1398 		    "cpu%d: failed to start, error %d", cp->cpu_id, error);
1399 		mach_cpucontext_free(cp, ctx, error);
1400 		return (error);
1401 	}
1402 
1403 	for (delays = 0, tempset = procset_slave; !CPU_IN_SET(tempset, cpuid);
1404 	    delays++) {
1405 		if (delays == 500) {
1406 			/*
1407 			 * After five seconds, things are probably looking
1408 			 * a bit bleak - explain the hang.
1409 			 */
1410 			cmn_err(CE_NOTE, "cpu%d: started, "
1411 			    "but not running in the kernel yet", cpuid);
1412 		} else if (delays > 2000) {
1413 			/*
1414 			 * We waited at least 20 seconds, bail ..
1415 			 */
1416 			error = ETIMEDOUT;
1417 			cmn_err(CE_WARN, "cpu%d: timed out", cpuid);
1418 			mach_cpucontext_free(cp, ctx, error);
1419 			return (error);
1420 		}
1421 
1422 		/*
1423 		 * wait at least 10ms, then check again..
1424 		 */
1425 		delay(USEC_TO_TICK_ROUNDUP(10000));
1426 		tempset = *((volatile cpuset_t *)&procset_slave);
1427 	}
1428 	CPUSET_ATOMIC_DEL(procset_slave, cpuid);
1429 
1430 	mach_cpucontext_free(cp, ctx, 0);
1431 
1432 #ifndef __xpv
1433 	if (tsc_gethrtime_enable)
1434 		tsc_sync_master(cpuid);
1435 #endif
1436 
1437 	if (dtrace_cpu_init != NULL) {
1438 		(*dtrace_cpu_init)(cpuid);
1439 	}
1440 
1441 	/*
1442 	 * During CPU DR operations, the cpu_lock is held by current
1443 	 * (the control) thread. We can't release the cpu_lock here
1444 	 * because that will break the CPU DR logic.
1445 	 * On the other hand, CPUPM and processor group initialization
1446 	 * routines need to access the cpu_lock. So we invoke those
1447 	 * routines here on behalf of mp_startup_common().
1448 	 *
1449 	 * CPUPM and processor group initialization routines depend
1450 	 * on the cpuid probing results. Wait for mp_startup_common()
1451 	 * to signal that cpuid probing is done.
1452 	 */
1453 	mp_startup_wait(&procset_slave, cpuid);
1454 #ifndef __xpv
1455 	cpupm_init(cp);
1456 #endif
1457 	(void) pg_cpu_init(cp, B_FALSE);
1458 	cpu_set_state(cp);
1459 	mp_startup_signal(&procset_master, cpuid);
1460 
1461 	return (0);
1462 }
1463 
1464 /*
1465  * Start a single cpu, assuming that the kernel context is available
1466  * to successfully start another cpu.
1467  *
1468  * (For example, real mode code is mapped into the right place
1469  * in memory and is ready to be run.)
1470  */
1471 int
1472 start_cpu(processorid_t who)
1473 {
1474 	cpu_t *cp;
1475 	int error = 0;
1476 	cpuset_t tempset;
1477 
1478 	ASSERT(who != 0);
1479 
1480 	/*
1481 	 * Check if there's at least a Mbyte of kmem available
1482 	 * before attempting to start the cpu.
1483 	 */
1484 	if (kmem_avail() < 1024 * 1024) {
1485 		/*
1486 		 * Kick off a reap in case that helps us with
1487 		 * later attempts ..
1488 		 */
1489 		kmem_reap();
1490 		return (ENOMEM);
1491 	}
1492 
1493 	/*
1494 	 * First configure cpu.
1495 	 */
1496 	cp = mp_cpu_configure_common(who, B_TRUE);
1497 	ASSERT(cp != NULL);
1498 
1499 	/*
1500 	 * Then start cpu.
1501 	 */
1502 	error = mp_start_cpu_common(cp, B_TRUE);
1503 	if (error != 0) {
1504 		mp_cpu_unconfigure_common(cp, error);
1505 		return (error);
1506 	}
1507 
1508 	mutex_exit(&cpu_lock);
1509 	tempset = cpu_ready_set;
1510 	while (!CPU_IN_SET(tempset, who)) {
1511 		drv_usecwait(1);
1512 		tempset = *((volatile cpuset_t *)&cpu_ready_set);
1513 	}
1514 	mutex_enter(&cpu_lock);
1515 
1516 	return (0);
1517 }
1518 
1519 void
1520 start_other_cpus(int cprboot)
1521 {
1522 	_NOTE(ARGUNUSED(cprboot));
1523 
1524 	uint_t who;
1525 	uint_t bootcpuid = 0;
1526 
1527 	/*
1528 	 * Initialize our own cpu_info.
1529 	 */
1530 	init_cpu_info(CPU);
1531 
1532 #if !defined(__xpv)
1533 	init_cpu_id_gdt(CPU);
1534 #endif
1535 
1536 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_idstr);
1537 	cmn_err(CE_CONT, "?cpu%d: %s\n", CPU->cpu_id, CPU->cpu_brandstr);
1538 
1539 	/*
1540 	 * KPTI initialisation happens very early in boot, before logging is
1541 	 * set up. Output a status message now as the boot CPU comes online.
1542 	 */
1543 	cmn_err(CE_CONT, "?KPTI %s (PCID %s, INVPCID %s)\n",
1544 	    kpti_enable ? "enabled" : "disabled",
1545 	    x86_use_pcid == 1 ? "in use" :
1546 	    (is_x86_feature(x86_featureset, X86FSET_PCID) ? "disabled" :
1547 	    "not supported"),
1548 	    x86_use_pcid == 1 && x86_use_invpcid == 1 ? "in use" :
1549 	    (is_x86_feature(x86_featureset, X86FSET_INVPCID) ? "disabled" :
1550 	    "not supported"));
1551 
1552 	/*
1553 	 * Initialize our syscall handlers
1554 	 */
1555 	init_cpu_syscall(CPU);
1556 
1557 	/*
1558 	 * Take the boot cpu out of the mp_cpus set because we know
1559 	 * it's already running.  Add it to the cpu_ready_set for
1560 	 * precisely the same reason.
1561 	 */
1562 	CPUSET_DEL(mp_cpus, bootcpuid);
1563 	CPUSET_ADD(cpu_ready_set, bootcpuid);
1564 
1565 	/*
1566 	 * skip the rest of this if
1567 	 * . only 1 cpu dectected and system isn't hotplug-capable
1568 	 * . not using MP
1569 	 */
1570 	if ((CPUSET_ISNULL(mp_cpus) && plat_dr_support_cpu() == 0) ||
1571 	    use_mp == 0) {
1572 		if (use_mp == 0)
1573 			cmn_err(CE_CONT, "?***** Not in MP mode\n");
1574 		goto done;
1575 	}
1576 
1577 	/*
1578 	 * perform such initialization as is needed
1579 	 * to be able to take CPUs on- and off-line.
1580 	 */
1581 	cpu_pause_init();
1582 
1583 	xc_init_cpu(CPU);		/* initialize processor crosscalls */
1584 
1585 	if (mach_cpucontext_init() != 0)
1586 		goto done;
1587 
1588 	flushes_require_xcalls = 1;
1589 
1590 	/*
1591 	 * We lock our affinity to the master CPU to ensure that all slave CPUs
1592 	 * do their TSC syncs with the same CPU.
1593 	 */
1594 	affinity_set(CPU_CURRENT);
1595 
1596 	for (who = 0; who < NCPU; who++) {
1597 		if (!CPU_IN_SET(mp_cpus, who))
1598 			continue;
1599 		ASSERT(who != bootcpuid);
1600 
1601 		mutex_enter(&cpu_lock);
1602 		if (start_cpu(who) != 0)
1603 			CPUSET_DEL(mp_cpus, who);
1604 		cpu_state_change_notify(who, CPU_SETUP);
1605 		mutex_exit(&cpu_lock);
1606 	}
1607 
1608 	/* Free the space allocated to hold the microcode file */
1609 	ucode_cleanup();
1610 
1611 	affinity_clear();
1612 
1613 	mach_cpucontext_fini();
1614 
1615 done:
1616 	if (get_hwenv() == HW_NATIVE)
1617 		workaround_errata_end();
1618 	cmi_post_mpstartup();
1619 
1620 #if !defined(__xpv)
1621 	/*
1622 	 * Once other CPUs have completed startup procedures, perform
1623 	 * initialization of hypervisor resources for HMA.
1624 	 */
1625 	hma_init();
1626 #endif
1627 
1628 	if (use_mp && ncpus != boot_max_ncpus) {
1629 		cmn_err(CE_NOTE,
1630 		    "System detected %d cpus, but "
1631 		    "only %d cpu(s) were enabled during boot.",
1632 		    boot_max_ncpus, ncpus);
1633 		cmn_err(CE_NOTE,
1634 		    "Use \"boot-ncpus\" parameter to enable more CPU(s). "
1635 		    "See eeprom(1M).");
1636 	}
1637 }
1638 
1639 int
1640 mp_cpu_configure(int cpuid)
1641 {
1642 	cpu_t *cp;
1643 
1644 	if (use_mp == 0 || plat_dr_support_cpu() == 0) {
1645 		return (ENOTSUP);
1646 	}
1647 
1648 	cp = cpu_get(cpuid);
1649 	if (cp != NULL) {
1650 		return (EALREADY);
1651 	}
1652 
1653 	/*
1654 	 * Check if there's at least a Mbyte of kmem available
1655 	 * before attempting to start the cpu.
1656 	 */
1657 	if (kmem_avail() < 1024 * 1024) {
1658 		/*
1659 		 * Kick off a reap in case that helps us with
1660 		 * later attempts ..
1661 		 */
1662 		kmem_reap();
1663 		return (ENOMEM);
1664 	}
1665 
1666 	cp = mp_cpu_configure_common(cpuid, B_FALSE);
1667 	ASSERT(cp != NULL && cpu_get(cpuid) == cp);
1668 
1669 	return (cp != NULL ? 0 : EAGAIN);
1670 }
1671 
1672 int
1673 mp_cpu_unconfigure(int cpuid)
1674 {
1675 	cpu_t *cp;
1676 
1677 	if (use_mp == 0 || plat_dr_support_cpu() == 0) {
1678 		return (ENOTSUP);
1679 	} else if (cpuid < 0 || cpuid >= max_ncpus) {
1680 		return (EINVAL);
1681 	}
1682 
1683 	cp = cpu_get(cpuid);
1684 	if (cp == NULL) {
1685 		return (ENODEV);
1686 	}
1687 	mp_cpu_unconfigure_common(cp, 0);
1688 
1689 	return (0);
1690 }
1691 
1692 /*
1693  * Startup function for 'other' CPUs (besides boot cpu).
1694  * Called from real_mode_start.
1695  *
1696  * WARNING: until CPU_READY is set, mp_startup_common and routines called by
1697  * mp_startup_common should not call routines (e.g. kmem_free) that could call
1698  * hat_unload which requires CPU_READY to be set.
1699  */
1700 static void
1701 mp_startup_common(boolean_t boot)
1702 {
1703 	cpu_t *cp = CPU;
1704 	uchar_t new_x86_featureset[BT_SIZEOFMAP(NUM_X86_FEATURES)];
1705 	extern void cpu_event_init_cpu(cpu_t *);
1706 
1707 	/*
1708 	 * We need to get TSC on this proc synced (i.e., any delta
1709 	 * from cpu0 accounted for) as soon as we can, because many
1710 	 * many things use gethrtime/pc_gethrestime, including
1711 	 * interrupts, cmn_err, etc.  Before we can do that, we want to
1712 	 * clear TSC if we're on a buggy Sandy/Ivy Bridge CPU, so do that
1713 	 * right away.
1714 	 */
1715 	bzero(new_x86_featureset, BT_SIZEOFMAP(NUM_X86_FEATURES));
1716 	cpuid_pass1(cp, new_x86_featureset);
1717 
1718 	if (boot && get_hwenv() == HW_NATIVE &&
1719 	    cpuid_getvendor(CPU) == X86_VENDOR_Intel &&
1720 	    cpuid_getfamily(CPU) == 6 &&
1721 	    (cpuid_getmodel(CPU) == 0x2d || cpuid_getmodel(CPU) == 0x3e) &&
1722 	    is_x86_feature(new_x86_featureset, X86FSET_TSC)) {
1723 		(void) wrmsr(REG_TSC, 0UL);
1724 	}
1725 
1726 	/* Let the control CPU continue into tsc_sync_master() */
1727 	mp_startup_signal(&procset_slave, cp->cpu_id);
1728 
1729 #ifndef __xpv
1730 	if (tsc_gethrtime_enable)
1731 		tsc_sync_slave();
1732 #endif
1733 
1734 	/*
1735 	 * Once this was done from assembly, but it's safer here; if
1736 	 * it blocks, we need to be able to swtch() to and from, and
1737 	 * since we get here by calling t_pc, we need to do that call
1738 	 * before swtch() overwrites it.
1739 	 */
1740 	(void) (*ap_mlsetup)();
1741 
1742 #ifndef __xpv
1743 	/*
1744 	 * Program this cpu's PAT
1745 	 */
1746 	pat_sync();
1747 #endif
1748 
1749 	/*
1750 	 * Set up TSC_AUX to contain the cpuid for this processor
1751 	 * for the rdtscp instruction.
1752 	 */
1753 	if (is_x86_feature(x86_featureset, X86FSET_TSCP))
1754 		(void) wrmsr(MSR_AMD_TSCAUX, cp->cpu_id);
1755 
1756 	/*
1757 	 * Initialize this CPU's syscall handlers
1758 	 */
1759 	init_cpu_syscall(cp);
1760 
1761 	/*
1762 	 * Enable interrupts with spl set to LOCK_LEVEL. LOCK_LEVEL is the
1763 	 * highest level at which a routine is permitted to block on
1764 	 * an adaptive mutex (allows for cpu poke interrupt in case
1765 	 * the cpu is blocked on a mutex and halts). Setting LOCK_LEVEL blocks
1766 	 * device interrupts that may end up in the hat layer issuing cross
1767 	 * calls before CPU_READY is set.
1768 	 */
1769 	splx(ipltospl(LOCK_LEVEL));
1770 	sti();
1771 
1772 	/*
1773 	 * There exists a small subset of systems which expose differing
1774 	 * MWAIT/MONITOR support between CPUs.  If MWAIT support is absent from
1775 	 * the boot CPU, but is found on a later CPU, the system continues to
1776 	 * operate as if no MWAIT support is available.
1777 	 *
1778 	 * The reverse case, where MWAIT is available on the boot CPU but not
1779 	 * on a subsequently initialized CPU, is not presently allowed and will
1780 	 * result in a panic.
1781 	 */
1782 	if (is_x86_feature(x86_featureset, X86FSET_MWAIT) !=
1783 	    is_x86_feature(new_x86_featureset, X86FSET_MWAIT)) {
1784 		if (!is_x86_feature(x86_featureset, X86FSET_MWAIT)) {
1785 			remove_x86_feature(new_x86_featureset, X86FSET_MWAIT);
1786 		} else {
1787 			panic("unsupported mixed cpu mwait support detected");
1788 		}
1789 	}
1790 
1791 	/*
1792 	 * We could be more sophisticated here, and just mark the CPU
1793 	 * as "faulted" but at this point we'll opt for the easier
1794 	 * answer of dying horribly.  Provided the boot cpu is ok,
1795 	 * the system can be recovered by booting with use_mp set to zero.
1796 	 */
1797 	if (workaround_errata(cp) != 0)
1798 		panic("critical workaround(s) missing for cpu%d", cp->cpu_id);
1799 
1800 	/*
1801 	 * We can touch cpu_flags here without acquiring the cpu_lock here
1802 	 * because the cpu_lock is held by the control CPU which is running
1803 	 * mp_start_cpu_common().
1804 	 * Need to clear CPU_QUIESCED flag before calling any function which
1805 	 * may cause thread context switching, such as kmem_alloc() etc.
1806 	 * The idle thread checks for CPU_QUIESCED flag and loops for ever if
1807 	 * it's set. So the startup thread may have no chance to switch back
1808 	 * again if it's switched away with CPU_QUIESCED set.
1809 	 */
1810 	cp->cpu_flags &= ~(CPU_POWEROFF | CPU_QUIESCED);
1811 
1812 	enable_pcid();
1813 
1814 	/*
1815 	 * Setup this processor for XSAVE.
1816 	 */
1817 	if (fp_save_mech == FP_XSAVE) {
1818 		xsave_setup_msr(cp);
1819 	}
1820 
1821 	cpuid_pass2(cp);
1822 	cpuid_pass3(cp);
1823 	cpuid_pass4(cp, NULL);
1824 
1825 	/*
1826 	 * Correct cpu_idstr and cpu_brandstr on target CPU after
1827 	 * cpuid_pass1() is done.
1828 	 */
1829 	(void) cpuid_getidstr(cp, cp->cpu_idstr, CPU_IDSTRLEN);
1830 	(void) cpuid_getbrandstr(cp, cp->cpu_brandstr, CPU_IDSTRLEN);
1831 
1832 	cp->cpu_flags |= CPU_RUNNING | CPU_READY | CPU_EXISTS;
1833 
1834 	post_startup_cpu_fixups();
1835 
1836 	cpu_event_init_cpu(cp);
1837 
1838 	/*
1839 	 * Enable preemption here so that contention for any locks acquired
1840 	 * later in mp_startup_common may be preempted if the thread owning
1841 	 * those locks is continuously executing on other CPUs (for example,
1842 	 * this CPU must be preemptible to allow other CPUs to pause it during
1843 	 * their startup phases).  It's safe to enable preemption here because
1844 	 * the CPU state is pretty-much fully constructed.
1845 	 */
1846 	curthread->t_preempt = 0;
1847 
1848 	/* The base spl should still be at LOCK LEVEL here */
1849 	ASSERT(cp->cpu_base_spl == ipltospl(LOCK_LEVEL));
1850 	set_base_spl();		/* Restore the spl to its proper value */
1851 
1852 	pghw_physid_create(cp);
1853 	/*
1854 	 * Delegate initialization tasks, which need to access the cpu_lock,
1855 	 * to mp_start_cpu_common() because we can't acquire the cpu_lock here
1856 	 * during CPU DR operations.
1857 	 */
1858 	mp_startup_signal(&procset_slave, cp->cpu_id);
1859 	mp_startup_wait(&procset_master, cp->cpu_id);
1860 	pg_cmt_cpu_startup(cp);
1861 
1862 	if (boot) {
1863 		mutex_enter(&cpu_lock);
1864 		cp->cpu_flags &= ~CPU_OFFLINE;
1865 		cpu_enable_intr(cp);
1866 		cpu_add_active(cp);
1867 		mutex_exit(&cpu_lock);
1868 	}
1869 
1870 	/* Enable interrupts */
1871 	(void) spl0();
1872 
1873 	/*
1874 	 * Fill out cpu_ucode_info.  Update microcode if necessary. Note that
1875 	 * this is done after pass1 on the boot CPU, but it needs to be later on
1876 	 * for the other CPUs.
1877 	 */
1878 	ucode_check(cp);
1879 	cpuid_pass_ucode(cp, new_x86_featureset);
1880 
1881 	/*
1882 	 * Do a sanity check to make sure this new CPU is a sane thing
1883 	 * to add to the collection of processors running this system.
1884 	 *
1885 	 * XXX	Clearly this needs to get more sophisticated, if x86
1886 	 * systems start to get built out of heterogenous CPUs; as is
1887 	 * likely to happen once the number of processors in a configuration
1888 	 * gets large enough.
1889 	 */
1890 	if (compare_x86_featureset(x86_featureset, new_x86_featureset) ==
1891 	    B_FALSE) {
1892 		cmn_err(CE_CONT, "cpu%d: featureset\n", cp->cpu_id);
1893 		print_x86_featureset(new_x86_featureset);
1894 		cmn_err(CE_WARN, "cpu%d feature mismatch", cp->cpu_id);
1895 	}
1896 
1897 #ifndef __xpv
1898 	{
1899 		/*
1900 		 * Set up the CPU module for this CPU.  This can't be done
1901 		 * before this CPU is made CPU_READY, because we may (in
1902 		 * heterogeneous systems) need to go load another CPU module.
1903 		 * The act of attempting to load a module may trigger a
1904 		 * cross-call, which will ASSERT unless this cpu is CPU_READY.
1905 		 */
1906 		cmi_hdl_t hdl;
1907 
1908 		if ((hdl = cmi_init(CMI_HDL_NATIVE, cmi_ntv_hwchipid(CPU),
1909 		    cmi_ntv_hwcoreid(CPU), cmi_ntv_hwstrandid(CPU))) != NULL) {
1910 			if (is_x86_feature(x86_featureset, X86FSET_MCA))
1911 				cmi_mca_init(hdl);
1912 			cp->cpu_m.mcpu_cmi_hdl = hdl;
1913 		}
1914 	}
1915 #endif /* __xpv */
1916 
1917 	if (boothowto & RB_DEBUG)
1918 		kdi_cpu_init();
1919 
1920 	(void) mach_cpu_create_device_node(cp, NULL);
1921 
1922 	/*
1923 	 * Setting the bit in cpu_ready_set must be the last operation in
1924 	 * processor initialization; the boot CPU will continue to boot once
1925 	 * it sees this bit set for all active CPUs.
1926 	 */
1927 	CPUSET_ATOMIC_ADD(cpu_ready_set, cp->cpu_id);
1928 
1929 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_idstr);
1930 	cmn_err(CE_CONT, "?cpu%d: %s\n", cp->cpu_id, cp->cpu_brandstr);
1931 	cmn_err(CE_CONT, "?cpu%d initialization complete - online\n",
1932 	    cp->cpu_id);
1933 
1934 	/*
1935 	 * Now we are done with the startup thread, so free it up.
1936 	 */
1937 	thread_exit();
1938 	/*NOTREACHED*/
1939 }
1940 
1941 /*
1942  * Startup function for 'other' CPUs at boot time (besides boot cpu).
1943  */
1944 static void
1945 mp_startup_boot(void)
1946 {
1947 	mp_startup_common(B_TRUE);
1948 }
1949 
1950 /*
1951  * Startup function for hotplug CPUs at runtime.
1952  */
1953 void
1954 mp_startup_hotplug(void)
1955 {
1956 	mp_startup_common(B_FALSE);
1957 }
1958 
1959 /*
1960  * Start CPU on user request.
1961  */
1962 /* ARGSUSED */
1963 int
1964 mp_cpu_start(struct cpu *cp)
1965 {
1966 	ASSERT(MUTEX_HELD(&cpu_lock));
1967 	return (0);
1968 }
1969 
1970 /*
1971  * Stop CPU on user request.
1972  */
1973 int
1974 mp_cpu_stop(struct cpu *cp)
1975 {
1976 	extern int cbe_psm_timer_mode;
1977 	ASSERT(MUTEX_HELD(&cpu_lock));
1978 
1979 #ifdef __xpv
1980 	/*
1981 	 * We can't offline vcpu0.
1982 	 */
1983 	if (cp->cpu_id == 0)
1984 		return (EBUSY);
1985 #endif
1986 
1987 	/*
1988 	 * If TIMER_PERIODIC mode is used, CPU0 is the one running it;
1989 	 * can't stop it.  (This is true only for machines with no TSC.)
1990 	 */
1991 
1992 	if ((cbe_psm_timer_mode == TIMER_PERIODIC) && (cp->cpu_id == 0))
1993 		return (EBUSY);
1994 
1995 	return (0);
1996 }
1997 
1998 /*
1999  * Take the specified CPU out of participation in interrupts.
2000  *
2001  * Usually, we hold cpu_lock. But we cannot assert as such due to the
2002  * exception - i_cpr_save_context() - where we have mutual exclusion via a
2003  * separate mechanism.
2004  */
2005 int
2006 cpu_disable_intr(struct cpu *cp)
2007 {
2008 	if (psm_disable_intr(cp->cpu_id) != DDI_SUCCESS)
2009 		return (EBUSY);
2010 
2011 	cp->cpu_flags &= ~CPU_ENABLE;
2012 	ncpus_intr_enabled--;
2013 	return (0);
2014 }
2015 
2016 /*
2017  * Allow the specified CPU to participate in interrupts.
2018  */
2019 void
2020 cpu_enable_intr(struct cpu *cp)
2021 {
2022 	ASSERT(MUTEX_HELD(&cpu_lock));
2023 	cp->cpu_flags |= CPU_ENABLE;
2024 	ncpus_intr_enabled++;
2025 	psm_enable_intr(cp->cpu_id);
2026 }
2027 
2028 void
2029 mp_cpu_faulted_enter(struct cpu *cp)
2030 {
2031 #ifdef __xpv
2032 	_NOTE(ARGUNUSED(cp));
2033 #else
2034 	cmi_hdl_t hdl = cp->cpu_m.mcpu_cmi_hdl;
2035 
2036 	if (hdl != NULL) {
2037 		cmi_hdl_hold(hdl);
2038 	} else {
2039 		hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
2040 		    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
2041 	}
2042 	if (hdl != NULL) {
2043 		cmi_faulted_enter(hdl);
2044 		cmi_hdl_rele(hdl);
2045 	}
2046 #endif
2047 }
2048 
2049 void
2050 mp_cpu_faulted_exit(struct cpu *cp)
2051 {
2052 #ifdef __xpv
2053 	_NOTE(ARGUNUSED(cp));
2054 #else
2055 	cmi_hdl_t hdl = cp->cpu_m.mcpu_cmi_hdl;
2056 
2057 	if (hdl != NULL) {
2058 		cmi_hdl_hold(hdl);
2059 	} else {
2060 		hdl = cmi_hdl_lookup(CMI_HDL_NATIVE, cmi_ntv_hwchipid(cp),
2061 		    cmi_ntv_hwcoreid(cp), cmi_ntv_hwstrandid(cp));
2062 	}
2063 	if (hdl != NULL) {
2064 		cmi_faulted_exit(hdl);
2065 		cmi_hdl_rele(hdl);
2066 	}
2067 #endif
2068 }
2069 
2070 /*
2071  * The following two routines are used as context operators on threads belonging
2072  * to processes with a private LDT (see sysi86).  Due to the rarity of such
2073  * processes, these routines are currently written for best code readability and
2074  * organization rather than speed.  We could avoid checking x86_featureset at
2075  * every context switch by installing different context ops, depending on
2076  * x86_featureset, at LDT creation time -- one for each combination of fast
2077  * syscall features.
2078  */
2079 
2080 void
2081 cpu_fast_syscall_disable(void)
2082 {
2083 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
2084 	    is_x86_feature(x86_featureset, X86FSET_SEP))
2085 		cpu_sep_disable();
2086 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
2087 	    is_x86_feature(x86_featureset, X86FSET_ASYSC))
2088 		cpu_asysc_disable();
2089 }
2090 
2091 void
2092 cpu_fast_syscall_enable(void)
2093 {
2094 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
2095 	    is_x86_feature(x86_featureset, X86FSET_SEP))
2096 		cpu_sep_enable();
2097 	if (is_x86_feature(x86_featureset, X86FSET_MSR) &&
2098 	    is_x86_feature(x86_featureset, X86FSET_ASYSC))
2099 		cpu_asysc_enable();
2100 }
2101 
2102 static void
2103 cpu_sep_enable(void)
2104 {
2105 	ASSERT(is_x86_feature(x86_featureset, X86FSET_SEP));
2106 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
2107 
2108 	wrmsr(MSR_INTC_SEP_CS, (uint64_t)(uintptr_t)KCS_SEL);
2109 }
2110 
2111 static void
2112 cpu_sep_disable(void)
2113 {
2114 	ASSERT(is_x86_feature(x86_featureset, X86FSET_SEP));
2115 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
2116 
2117 	/*
2118 	 * Setting the SYSENTER_CS_MSR register to 0 causes software executing
2119 	 * the sysenter or sysexit instruction to trigger a #gp fault.
2120 	 */
2121 	wrmsr(MSR_INTC_SEP_CS, 0);
2122 }
2123 
2124 static void
2125 cpu_asysc_enable(void)
2126 {
2127 	ASSERT(is_x86_feature(x86_featureset, X86FSET_ASYSC));
2128 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
2129 
2130 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) |
2131 	    (uint64_t)(uintptr_t)AMD_EFER_SCE);
2132 }
2133 
2134 static void
2135 cpu_asysc_disable(void)
2136 {
2137 	ASSERT(is_x86_feature(x86_featureset, X86FSET_ASYSC));
2138 	ASSERT(curthread->t_preempt || getpil() >= LOCK_LEVEL);
2139 
2140 	/*
2141 	 * Turn off the SCE (syscall enable) bit in the EFER register. Software
2142 	 * executing syscall or sysret with this bit off will incur a #ud trap.
2143 	 */
2144 	wrmsr(MSR_AMD_EFER, rdmsr(MSR_AMD_EFER) &
2145 	    ~((uint64_t)(uintptr_t)AMD_EFER_SCE));
2146 }
2147