xref: /netbsd-src/sys/arch/xen/x86/cpu.c (revision c34236556bea94afcaca1782d7d228301edc3ea0)
1 /*	$NetBSD: cpu.c,v 1.105 2016/11/25 12:20:03 maxv Exp $	*/
2 
3 /*-
4  * Copyright (c) 2000 The NetBSD Foundation, Inc.
5  * Copyright (c) 2002, 2006, 2007 YAMAMOTO Takashi,
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by RedBack Networks Inc.
10  *
11  * Author: Bill Sommerfeld
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 /*
36  * Copyright (c) 1999 Stefan Grefen
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *      This product includes software developed by the NetBSD
49  *      Foundation, Inc. and its contributors.
50  * 4. Neither the name of The NetBSD Foundation nor the names of its
51  *    contributors may be used to endorse or promote products derived
52  *    from this software without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
55  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR AND CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  */
66 
67 #include <sys/cdefs.h>
68 __KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.105 2016/11/25 12:20:03 maxv Exp $");
69 
70 #include "opt_ddb.h"
71 #include "opt_multiprocessor.h"
72 #include "opt_mpbios.h"		/* for MPDEBUG */
73 #include "opt_mtrr.h"
74 #include "opt_xen.h"
75 
76 #include "lapic.h"
77 #include "ioapic.h"
78 
79 #include <sys/param.h>
80 #include <sys/proc.h>
81 #include <sys/systm.h>
82 #include <sys/device.h>
83 #include <sys/kmem.h>
84 #include <sys/cpu.h>
85 #include <sys/cpufreq.h>
86 #include <sys/atomic.h>
87 #include <sys/reboot.h>
88 #include <sys/idle.h>
89 
90 #include <uvm/uvm.h>
91 
92 #include <machine/cpufunc.h>
93 #include <machine/cpuvar.h>
94 #include <machine/pmap.h>
95 #include <machine/vmparam.h>
96 #include <machine/mpbiosvar.h>
97 #include <machine/pcb.h>
98 #include <machine/specialreg.h>
99 #include <machine/segments.h>
100 #include <machine/gdt.h>
101 #include <machine/mtrr.h>
102 #include <machine/pio.h>
103 
104 #include <x86/fpu.h>
105 
106 #include <xen/xen.h>
107 #include <xen/xen-public/vcpu.h>
108 #include <xen/vcpuvar.h>
109 
110 #if NLAPIC > 0
111 #include <machine/apicvar.h>
112 #include <machine/i82489reg.h>
113 #include <machine/i82489var.h>
114 #endif
115 
116 #include <dev/ic/mc146818reg.h>
117 #include <dev/isa/isareg.h>
118 
119 static int	cpu_match(device_t, cfdata_t, void *);
120 static void	cpu_attach(device_t, device_t, void *);
121 static void	cpu_defer(device_t);
122 static int	cpu_rescan(device_t, const char *, const int *);
123 static void	cpu_childdetached(device_t, device_t);
124 static int	vcpu_match(device_t, cfdata_t, void *);
125 static void	vcpu_attach(device_t, device_t, void *);
126 static void	cpu_attach_common(device_t, device_t, void *);
127 void		cpu_offline_md(void);
128 
129 struct cpu_softc {
130 	device_t sc_dev;		/* device tree glue */
131 	struct cpu_info *sc_info;	/* pointer to CPU info */
132 	bool sc_wasonline;
133 };
134 
135 int mp_cpu_start(struct cpu_info *, vaddr_t);
136 void mp_cpu_start_cleanup(struct cpu_info *);
137 const struct cpu_functions mp_cpu_funcs = { mp_cpu_start, NULL,
138 				      mp_cpu_start_cleanup };
139 
140 CFATTACH_DECL2_NEW(cpu, sizeof(struct cpu_softc),
141     cpu_match, cpu_attach, NULL, NULL, cpu_rescan, cpu_childdetached);
142 
143 CFATTACH_DECL_NEW(vcpu, sizeof(struct cpu_softc),
144     vcpu_match, vcpu_attach, NULL, NULL);
145 
146 /*
147  * Statically-allocated CPU info for the primary CPU (or the only
148  * CPU, on uniprocessors).  The CPU info list is initialized to
149  * point at it.
150  */
151 #ifdef TRAPLOG
152 #include <machine/tlog.h>
153 struct tlog tlog_primary;
154 #endif
155 struct cpu_info cpu_info_primary __aligned(CACHE_LINE_SIZE) = {
156 	.ci_dev = 0,
157 	.ci_self = &cpu_info_primary,
158 	.ci_idepth = -1,
159 	.ci_curlwp = &lwp0,
160 	.ci_curldt = -1,
161 #ifdef TRAPLOG
162 	.ci_tlog = &tlog_primary,
163 #endif
164 
165 };
166 struct cpu_info phycpu_info_primary __aligned(CACHE_LINE_SIZE) = {
167 	.ci_dev = 0,
168 	.ci_self = &phycpu_info_primary,
169 };
170 
171 struct cpu_info *cpu_info_list = &cpu_info_primary;
172 struct cpu_info *phycpu_info_list = &phycpu_info_primary;
173 
174 uint32_t cpu_feature[7]; /* X86 CPUID feature bits
175 			  *	[0] basic features %edx
176 			  *	[1] basic features %ecx
177 			  *	[2] extended features %edx
178 			  *	[3] extended features %ecx
179 			  *	[4] VIA padlock features
180 			  *	[5] structured extended features cpuid.7:%ebx
181 			  *	[6] structured extended features cpuid.7:%ecx
182 			  */
183 
184 bool x86_mp_online;
185 paddr_t mp_trampoline_paddr = MP_TRAMPOLINE;
186 
187 #if defined(MULTIPROCESSOR)
188 void    	cpu_hatch(void *);
189 static void    	cpu_boot_secondary(struct cpu_info *ci);
190 static void    	cpu_start_secondary(struct cpu_info *ci);
191 #endif	/* MULTIPROCESSOR */
192 
193 static int
194 cpu_match(device_t parent, cfdata_t match, void *aux)
195 {
196 
197 	return 1;
198 }
199 
200 static void
201 cpu_attach(device_t parent, device_t self, void *aux)
202 {
203 	struct cpu_softc *sc = device_private(self);
204 	struct cpu_attach_args *caa = aux;
205 	struct cpu_info *ci;
206 	uintptr_t ptr;
207 	static int nphycpu = 0;
208 
209 	sc->sc_dev = self;
210 
211 	/*
212 	 * If we're an Application Processor, allocate a cpu_info
213 	 * If we're the first attached CPU use the primary cpu_info,
214 	 * otherwise allocate a new one
215 	 */
216 	aprint_naive("\n");
217 	aprint_normal("\n");
218 	if (nphycpu > 0) {
219 		struct cpu_info *tmp;
220 		ptr = (uintptr_t)kmem_zalloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
221 		    KM_SLEEP);
222 		ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
223 		ci->ci_curldt = -1;
224 
225 		tmp = phycpu_info_list;
226 		while (tmp->ci_next)
227 			tmp = tmp->ci_next;
228 
229 		tmp->ci_next = ci;
230 	} else {
231 		ci = &phycpu_info_primary;
232 	}
233 
234 	ci->ci_self = ci;
235 	sc->sc_info = ci;
236 
237 	ci->ci_dev = self;
238 	ci->ci_acpiid = caa->cpu_id;
239 	ci->ci_cpuid = caa->cpu_number;
240 	ci->ci_vcpu = NULL;
241 	ci->ci_index = nphycpu++;
242 
243 	if (!pmf_device_register(self, NULL, NULL))
244 		aprint_error_dev(self, "couldn't establish power handler\n");
245 
246 	(void)config_defer(self, cpu_defer);
247 }
248 
249 static void
250 cpu_defer(device_t self)
251 {
252 	cpu_rescan(self, NULL, NULL);
253 }
254 
255 static int
256 cpu_rescan(device_t self, const char *ifattr, const int *locators)
257 {
258 	struct cpu_softc *sc = device_private(self);
259 	struct cpufeature_attach_args cfaa;
260 	struct cpu_info *ci = sc->sc_info;
261 
262 	memset(&cfaa, 0, sizeof(cfaa));
263 	cfaa.ci = ci;
264 
265 	if (ifattr_match(ifattr, "cpufeaturebus")) {
266 
267 		if (ci->ci_frequency == NULL) {
268 			cfaa.name = "frequency";
269 			ci->ci_frequency = config_found_ia(self,
270 			    "cpufeaturebus", &cfaa, NULL);
271 		}
272 	}
273 
274 	return 0;
275 }
276 
277 static void
278 cpu_childdetached(device_t self, device_t child)
279 {
280 	struct cpu_softc *sc = device_private(self);
281 	struct cpu_info *ci = sc->sc_info;
282 
283 	if (ci->ci_frequency == child)
284 		ci->ci_frequency = NULL;
285 }
286 
287 static int
288 vcpu_match(device_t parent, cfdata_t match, void *aux)
289 {
290 	struct vcpu_attach_args *vcaa = aux;
291 	struct vcpu_runstate_info vcr;
292 	int error;
293 
294 	if (strcmp(vcaa->vcaa_name, match->cf_name) == 0) {
295 		error = HYPERVISOR_vcpu_op(VCPUOP_get_runstate_info,
296 		    vcaa->vcaa_caa.cpu_number, &vcr);
297 		switch (error) {
298 		case 0:
299 			return 1;
300 		case -ENOENT:
301 			return 0;
302 		default:
303 			panic("Unknown hypervisor error %d returned on vcpu runstate probe\n", error);
304 		}
305 	}
306 
307 	return 0;
308 }
309 
310 static void
311 vcpu_attach(device_t parent, device_t self, void *aux)
312 {
313 	struct vcpu_attach_args *vcaa = aux;
314 
315 	KASSERT(vcaa->vcaa_caa.cpu_func == NULL);
316 	vcaa->vcaa_caa.cpu_func = &mp_cpu_funcs;
317 	cpu_attach_common(parent, self, &vcaa->vcaa_caa);
318 
319 	if (!pmf_device_register(self, NULL, NULL))
320 		aprint_error_dev(self, "couldn't establish power handler\n");
321 }
322 
323 static int
324 vcpu_is_up(struct cpu_info *ci)
325 {
326 	KASSERT(ci != NULL);
327 	return HYPERVISOR_vcpu_op(VCPUOP_is_up, ci->ci_cpuid, NULL);
328 }
329 
330 static void
331 cpu_vm_init(struct cpu_info *ci)
332 {
333 	int ncolors = 2, i;
334 
335 	for (i = CAI_ICACHE; i <= CAI_L2CACHE; i++) {
336 		struct x86_cache_info *cai;
337 		int tcolors;
338 
339 		cai = &ci->ci_cinfo[i];
340 
341 		tcolors = atop(cai->cai_totalsize);
342 		switch (cai->cai_associativity) {
343 		case 0xff:
344 			tcolors = 1; /* fully associative */
345 			break;
346 		case 0:
347 		case 1:
348 			break;
349 		default:
350 			tcolors /= cai->cai_associativity;
351 		}
352 		ncolors = max(ncolors, tcolors);
353 	}
354 
355 	/*
356 	 * Knowing the size of the largest cache on this CPU, potentially
357 	 * re-color our pages.
358 	 */
359 	aprint_debug_dev(ci->ci_dev, "%d page colors\n", ncolors);
360 	uvm_page_recolor(ncolors);
361 	pmap_tlb_cpu_init(ci);
362 }
363 
364 static void
365 cpu_attach_common(device_t parent, device_t self, void *aux)
366 {
367 	struct cpu_softc *sc = device_private(self);
368 	struct cpu_attach_args *caa = aux;
369 	struct cpu_info *ci;
370 	uintptr_t ptr;
371 	int cpunum = caa->cpu_number;
372 	static bool again = false;
373 
374 	sc->sc_dev = self;
375 
376 	/*
377 	 * If we're an Application Processor, allocate a cpu_info
378 	 * structure, otherwise use the primary's.
379 	 */
380 	if (caa->cpu_role == CPU_ROLE_AP) {
381 		aprint_naive(": Application Processor\n");
382 		ptr = (uintptr_t)kmem_alloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
383 		    KM_SLEEP);
384 		ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
385 		memset(ci, 0, sizeof(*ci));
386 #ifdef TRAPLOG
387 		ci->ci_tlog_base = kmem_zalloc(sizeof(struct tlog), KM_SLEEP);
388 #endif
389 	} else {
390 		aprint_naive(": %s Processor\n",
391 		    caa->cpu_role == CPU_ROLE_SP ? "Single" : "Boot");
392 		ci = &cpu_info_primary;
393 	}
394 
395 	ci->ci_self = ci;
396 	sc->sc_info = ci;
397 	ci->ci_dev = self;
398 	ci->ci_cpuid = cpunum;
399 
400 	KASSERT(HYPERVISOR_shared_info != NULL);
401 	KASSERT(cpunum < XEN_LEGACY_MAX_VCPUS);
402 	ci->ci_vcpu = &HYPERVISOR_shared_info->vcpu_info[cpunum];
403 
404 	KASSERT(ci->ci_func == 0);
405 	ci->ci_func = caa->cpu_func;
406 	aprint_normal("\n");
407 
408 	/* Must be called before mi_cpu_attach(). */
409 	cpu_vm_init(ci);
410 
411 	if (caa->cpu_role == CPU_ROLE_AP) {
412 		int error;
413 
414 		error = mi_cpu_attach(ci);
415 
416 		KASSERT(ci->ci_data.cpu_idlelwp != NULL);
417 		if (error != 0) {
418 			aprint_error_dev(self,
419 			    "mi_cpu_attach failed with %d\n", error);
420 			return;
421 		}
422 
423 	} else {
424 		KASSERT(ci->ci_data.cpu_idlelwp != NULL);
425 	}
426 
427 	KASSERT(ci->ci_cpuid == ci->ci_index);
428 #ifdef __x86_64__
429 	/* No user PGD mapped for this CPU yet */
430 	ci->ci_xen_current_user_pgd = 0;
431 #endif
432 #if defined(__x86_64__) || defined(PAE)
433 	mutex_init(&ci->ci_kpm_mtx, MUTEX_DEFAULT, IPL_VM);
434 #endif
435 	pmap_reference(pmap_kernel());
436 	ci->ci_pmap = pmap_kernel();
437 	ci->ci_tlbstate = TLBSTATE_STALE;
438 
439 	/*
440 	 * Boot processor may not be attached first, but the below
441 	 * must be done to allow booting other processors.
442 	 */
443 	if (!again) {
444 		atomic_or_32(&ci->ci_flags, CPUF_PRESENT | CPUF_PRIMARY);
445 		/* Basic init. */
446 		cpu_intr_init(ci);
447 		cpu_get_tsc_freq(ci);
448 		cpu_init(ci);
449 		pmap_cpu_init_late(ci);
450 
451 		/* Every processor needs to init its own ipi h/w (similar to lapic) */
452 		xen_ipi_init();
453 
454 		/* Make sure DELAY() is initialized. */
455 		DELAY(1);
456 		again = true;
457 	}
458 
459 	/* further PCB init done later. */
460 
461 	switch (caa->cpu_role) {
462 	case CPU_ROLE_SP:
463 		atomic_or_32(&ci->ci_flags, CPUF_SP);
464 		cpu_identify(ci);
465 		x86_cpu_idle_init();
466 		break;
467 
468 	case CPU_ROLE_BP:
469 		atomic_or_32(&ci->ci_flags, CPUF_BSP);
470 		cpu_identify(ci);
471 		x86_cpu_idle_init();
472 		break;
473 
474 	case CPU_ROLE_AP:
475 		atomic_or_32(&ci->ci_flags, CPUF_AP);
476 
477 		/*
478 		 * report on an AP
479 		 */
480 
481 #if defined(MULTIPROCESSOR)
482 		/* interrupt handler stack */
483 		cpu_intr_init(ci);
484 
485 		/* Setup per-cpu memory for gdt */
486 		gdt_alloc_cpu(ci);
487 
488 		pmap_cpu_init_late(ci);
489 		cpu_start_secondary(ci);
490 
491 		if (ci->ci_flags & CPUF_PRESENT) {
492 			struct cpu_info *tmp;
493 
494 			cpu_identify(ci);
495 			tmp = cpu_info_list;
496 			while (tmp->ci_next)
497 				tmp = tmp->ci_next;
498 
499 			tmp->ci_next = ci;
500 		}
501 #else
502 		aprint_error_dev(ci->ci_dev, "not started\n");
503 #endif
504 		break;
505 
506 	default:
507 		panic("unknown processor type??\n");
508 	}
509 
510 #ifdef MPVERBOSE
511 	if (mp_verbose) {
512 		struct lwp *l = ci->ci_data.cpu_idlelwp;
513 		struct pcb *pcb = lwp_getpcb(l);
514 
515 		aprint_verbose_dev(self,
516 		    "idle lwp at %p, idle sp at 0x%p\n",
517 		    l,
518 #ifdef i386
519 		    (void *)pcb->pcb_esp
520 #else
521 		    (void *)pcb->pcb_rsp
522 #endif
523 		);
524 
525 	}
526 #endif /* MPVERBOSE */
527 }
528 
529 /*
530  * Initialize the processor appropriately.
531  */
532 
533 void
534 cpu_init(struct cpu_info *ci)
535 {
536 
537 	/*
538 	 * If we have FXSAVE/FXRESTOR, use them.
539 	 */
540 	if (cpu_feature[0] & CPUID_FXSR) {
541 		lcr4(rcr4() | CR4_OSFXSR);
542 
543 		/*
544 		 * If we have SSE/SSE2, enable XMM exceptions.
545 		 */
546 		if (cpu_feature[0] & (CPUID_SSE|CPUID_SSE2))
547 			lcr4(rcr4() | CR4_OSXMMEXCPT);
548 	}
549 
550 	atomic_or_32(&ci->ci_flags, CPUF_RUNNING);
551 }
552 
553 
554 #ifdef MULTIPROCESSOR
555 
556 void
557 cpu_boot_secondary_processors(void)
558 {
559 	struct cpu_info *ci;
560 	u_long i;
561 	for (i = 0; i < maxcpus; i++) {
562 		ci = cpu_lookup(i);
563 		if (ci == NULL)
564 			continue;
565 		if (ci->ci_data.cpu_idlelwp == NULL)
566 			continue;
567 		if ((ci->ci_flags & CPUF_PRESENT) == 0)
568 			continue;
569 		if (ci->ci_flags & (CPUF_BSP|CPUF_SP|CPUF_PRIMARY))
570 			continue;
571 		cpu_boot_secondary(ci);
572 	}
573 
574 	x86_mp_online = true;
575 }
576 
577 static void
578 cpu_init_idle_lwp(struct cpu_info *ci)
579 {
580 	struct lwp *l = ci->ci_data.cpu_idlelwp;
581 	struct pcb *pcb = lwp_getpcb(l);
582 
583 	pcb->pcb_cr0 = rcr0();
584 }
585 
586 void
587 cpu_init_idle_lwps(void)
588 {
589 	struct cpu_info *ci;
590 	u_long i;
591 
592 	for (i = 0; i < maxcpus; i++) {
593 		ci = cpu_lookup(i);
594 		if (ci == NULL)
595 			continue;
596 		if (ci->ci_data.cpu_idlelwp == NULL)
597 			continue;
598 		if ((ci->ci_flags & CPUF_PRESENT) == 0)
599 			continue;
600 		cpu_init_idle_lwp(ci);
601 	}
602 }
603 
604 static void
605 cpu_start_secondary(struct cpu_info *ci)
606 {
607 	int i;
608 
609 	aprint_debug_dev(ci->ci_dev, "starting\n");
610 
611 	ci->ci_curlwp = ci->ci_data.cpu_idlelwp;
612 
613 	if (CPU_STARTUP(ci, (vaddr_t) cpu_hatch) != 0) {
614 		return;
615 	}
616 
617 	/*
618 	 * wait for it to become ready
619 	 */
620 	for (i = 100000; (!(ci->ci_flags & CPUF_PRESENT)) && i > 0; i--) {
621 		delay(10);
622 	}
623 	if ((ci->ci_flags & CPUF_PRESENT) == 0) {
624 		aprint_error_dev(ci->ci_dev, "failed to become ready\n");
625 #if defined(MPDEBUG) && defined(DDB)
626 		printf("dropping into debugger; continue from here to resume boot\n");
627 		Debugger();
628 #endif
629 	}
630 
631 	CPU_START_CLEANUP(ci);
632 }
633 
634 void
635 cpu_boot_secondary(struct cpu_info *ci)
636 {
637 	int i;
638 	atomic_or_32(&ci->ci_flags, CPUF_GO);
639 	for (i = 100000; (!(ci->ci_flags & CPUF_RUNNING)) && i > 0; i--) {
640 		delay(10);
641 	}
642 	if ((ci->ci_flags & CPUF_RUNNING) == 0) {
643 		aprint_error_dev(ci->ci_dev, "CPU failed to start\n");
644 #if defined(MPDEBUG) && defined(DDB)
645 		printf("dropping into debugger; continue from here to resume boot\n");
646 		Debugger();
647 #endif
648 	}
649 }
650 
651 /*
652  * APs end up here immediately after initialisation and VCPUOP_up in
653  * mp_cpu_start().
654  * At this point, we are running in the idle pcb/idle stack of the new
655  * CPU.  This function jumps to the idle loop and starts looking for
656  * work.
657  */
658 extern void x86_64_tls_switch(struct lwp *);
659 void
660 cpu_hatch(void *v)
661 {
662 	struct cpu_info *ci = (struct cpu_info *)v;
663 	struct pcb *pcb;
664 	int s, i;
665 
666 	/* Setup TLS and kernel GS/FS */
667 	cpu_init_msrs(ci, true);
668 	cpu_init_idt();
669 	gdt_init_cpu(ci);
670 
671 	cpu_probe(ci);
672 
673 	atomic_or_32(&ci->ci_flags, CPUF_PRESENT);
674 
675 	while ((ci->ci_flags & CPUF_GO) == 0) {
676 		/* Don't use delay, boot CPU may be patching the text. */
677 		for (i = 10000; i != 0; i--)
678 			x86_pause();
679 	}
680 
681 	/* Because the text may have been patched in x86_patch(). */
682 	x86_flush();
683 	tlbflushg();
684 
685 	KASSERT((ci->ci_flags & CPUF_RUNNING) == 0);
686 
687 	pcb = lwp_getpcb(curlwp);
688 	pcb->pcb_cr3 = pmap_pdirpa(pmap_kernel(), 0);
689 	pcb = lwp_getpcb(ci->ci_data.cpu_idlelwp);
690 
691 	xen_ipi_init();
692 
693 	xen_initclocks();
694 
695 #ifdef __x86_64__
696 	fpuinit(ci);
697 #endif
698 
699 	lldt(GSEL(GLDT_SEL, SEL_KPL));
700 
701 	cpu_init(ci);
702 	cpu_get_tsc_freq(ci);
703 
704 	s = splhigh();
705 	x86_enable_intr();
706 	splx(s);
707 
708 	aprint_debug_dev(ci->ci_dev, "running\n");
709 
710 	cpu_switchto(NULL, ci->ci_data.cpu_idlelwp, true);
711 
712 	idle_loop(NULL);
713 	KASSERT(false);
714 }
715 
716 #if defined(DDB)
717 
718 #include <ddb/db_output.h>
719 #include <machine/db_machdep.h>
720 
721 /*
722  * Dump CPU information from ddb.
723  */
724 void
725 cpu_debug_dump(void)
726 {
727 	struct cpu_info *ci;
728 	CPU_INFO_ITERATOR cii;
729 
730 	db_printf("addr		dev	id	flags	ipis	curlwp 		fpcurlwp\n");
731 	for (CPU_INFO_FOREACH(cii, ci)) {
732 		db_printf("%p	%s	%ld	%x	%x	%10p	%10p\n",
733 		    ci,
734 		    ci->ci_dev == NULL ? "BOOT" : device_xname(ci->ci_dev),
735 		    (long)ci->ci_cpuid,
736 		    ci->ci_flags, ci->ci_ipis,
737 		    ci->ci_curlwp,
738 		    ci->ci_fpcurlwp);
739 	}
740 }
741 #endif /* DDB */
742 
743 #endif /* MULTIPROCESSOR */
744 
745 extern void hypervisor_callback(void);
746 extern void failsafe_callback(void);
747 #ifdef __x86_64__
748 typedef void (vector)(void);
749 extern vector Xsyscall, Xsyscall32;
750 #endif
751 
752 /*
753  * Setup the "trampoline". On Xen, we setup nearly all cpu context
754  * outside a trampoline, so we prototype and call targetip like so:
755  * void targetip(struct cpu_info *);
756  */
757 
758 static void
759 gdt_prepframes(paddr_t *frames, vaddr_t base, uint32_t entries)
760 {
761 	int i;
762 	for (i = 0; i < roundup(entries, PAGE_SIZE) >> PAGE_SHIFT; i++) {
763 		frames[i] = ((paddr_t)xpmap_ptetomach(
764 		    (pt_entry_t *)(base + (i << PAGE_SHIFT)))) >> PAGE_SHIFT;
765 
766 		/* Mark Read-only */
767 		pmap_pte_clearbits(kvtopte(base + (i << PAGE_SHIFT)),
768 		    PG_RW);
769 	}
770 }
771 
772 #ifdef __x86_64__
773 extern char *ldtstore;
774 
775 static void
776 xen_init_amd64_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
777     void targetrip(struct cpu_info *))
778 {
779 	/* page frames to point at GDT */
780 	extern int gdt_size;
781 	paddr_t frames[16];
782 	psize_t gdt_ents;
783 
784 	struct lwp *l;
785 	struct pcb *pcb;
786 
787 	volatile struct vcpu_info *vci;
788 
789 	KASSERT(ci != NULL);
790 	KASSERT(ci != &cpu_info_primary);
791 	KASSERT(initctx != NULL);
792 	KASSERT(targetrip != NULL);
793 
794 	memset(initctx, 0, sizeof(*initctx));
795 
796 	gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
797 	KASSERT(gdt_ents <= 16);
798 
799 	gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);
800 
801 	/* Initialise the vcpu context: We use idle_loop()'s pcb context. */
802 
803 	l = ci->ci_data.cpu_idlelwp;
804 
805 	KASSERT(l != NULL);
806 	pcb = lwp_getpcb(l);
807 	KASSERT(pcb != NULL);
808 
809 	/* resume with interrupts off */
810 	vci = ci->ci_vcpu;
811 	vci->evtchn_upcall_mask = 1;
812 	xen_mb();
813 
814 	/* resume in kernel-mode */
815 	initctx->flags = VGCF_in_kernel | VGCF_online;
816 
817 	/* Stack and entry points:
818 	 * We arrange for the stack frame for cpu_hatch() to
819 	 * appear as a callee frame of lwp_trampoline(). Being a
820 	 * leaf frame prevents trampling on any of the MD stack setup
821 	 * that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
822 	 */
823 
824 	initctx->user_regs.rdi = (uint64_t) ci; /* targetrip(ci); */
825 	initctx->user_regs.rip = (vaddr_t) targetrip;
826 
827 	initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);
828 
829 	initctx->user_regs.rflags = pcb->pcb_flags;
830 	initctx->user_regs.rsp = pcb->pcb_rsp;
831 
832 	/* Data segments */
833 	initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
834 	initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
835 	initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);
836 
837 	/* GDT */
838 	memcpy(initctx->gdt_frames, frames, sizeof(frames));
839 	initctx->gdt_ents = gdt_ents;
840 
841 	/* LDT */
842 	initctx->ldt_base = (unsigned long)ldtstore;
843 	initctx->ldt_ents = LDT_SIZE >> 3;
844 
845 	/* Kernel context state */
846 	initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
847 	initctx->kernel_sp = pcb->pcb_rsp0;
848 	initctx->ctrlreg[0] = pcb->pcb_cr0;
849 	initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
850 	initctx->ctrlreg[2] = (vaddr_t)targetrip;
851 	/*
852 	 * Use pmap_kernel() L4 PD directly, until we setup the
853 	 * per-cpu L4 PD in pmap_cpu_init_late()
854 	 */
855 	initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_kpm_pdirpa)));
856 	initctx->ctrlreg[4] = CR4_PAE | CR4_OSFXSR | CR4_OSXMMEXCPT;
857 
858 	/* Xen callbacks */
859 	initctx->event_callback_eip = (unsigned long)hypervisor_callback;
860 	initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
861 	initctx->syscall_callback_eip = (unsigned long)Xsyscall;
862 
863 	return;
864 }
865 #else /* i386 */
866 extern union descriptor *ldt;
867 extern void Xsyscall(void);
868 
869 static void
870 xen_init_i386_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
871     void targeteip(struct cpu_info *))
872 {
873 	/* page frames to point at GDT */
874 	extern int gdt_size;
875 	paddr_t frames[16];
876 	psize_t gdt_ents;
877 
878 	struct lwp *l;
879 	struct pcb *pcb;
880 
881 	volatile struct vcpu_info *vci;
882 
883 	KASSERT(ci != NULL);
884 	KASSERT(ci != &cpu_info_primary);
885 	KASSERT(initctx != NULL);
886 	KASSERT(targeteip != NULL);
887 
888 	memset(initctx, 0, sizeof(*initctx));
889 
890 	gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
891 	KASSERT(gdt_ents <= 16);
892 
893 	gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);
894 
895 	/*
896 	 * Initialise the vcpu context:
897 	 * We use this cpu's idle_loop() pcb context.
898 	 */
899 
900 	l = ci->ci_data.cpu_idlelwp;
901 
902 	KASSERT(l != NULL);
903 	pcb = lwp_getpcb(l);
904 	KASSERT(pcb != NULL);
905 
906 	/* resume with interrupts off */
907 	vci = ci->ci_vcpu;
908 	vci->evtchn_upcall_mask = 1;
909 	xen_mb();
910 
911 	/* resume in kernel-mode */
912 	initctx->flags = VGCF_in_kernel | VGCF_online;
913 
914 	/* Stack frame setup for cpu_hatch():
915 	 * We arrange for the stack frame for cpu_hatch() to
916 	 * appear as a callee frame of lwp_trampoline(). Being a
917 	 * leaf frame prevents trampling on any of the MD stack setup
918 	 * that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
919 	 */
920 
921 	initctx->user_regs.esp = pcb->pcb_esp - 4; /* Leave word for
922 						      arg1 */
923 	{
924 		/* targeteip(ci); */
925 		uint32_t *arg = (uint32_t *)initctx->user_regs.esp;
926 		arg[1] = (uint32_t)ci; /* arg1 */
927 	}
928 
929 	initctx->user_regs.eip = (vaddr_t)targeteip;
930 	initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);
931 	initctx->user_regs.eflags |= pcb->pcb_iopl;
932 
933 	/* Data segments */
934 	initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
935 	initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
936 	initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);
937 	initctx->user_regs.fs = GSEL(GDATA_SEL, SEL_KPL);
938 
939 	/* GDT */
940 	memcpy(initctx->gdt_frames, frames, sizeof(frames));
941 	initctx->gdt_ents = gdt_ents;
942 
943 	/* LDT */
944 	initctx->ldt_base = (unsigned long)ldt;
945 	initctx->ldt_ents = NLDT;
946 
947 	/* Kernel context state */
948 	initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
949 	initctx->kernel_sp = pcb->pcb_esp0;
950 	initctx->ctrlreg[0] = pcb->pcb_cr0;
951 	initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
952 	initctx->ctrlreg[2] = (vaddr_t)targeteip;
953 #ifdef PAE
954 	initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_pae_l3_pdirpa)));
955 #else
956 	initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(pcb->pcb_cr3)));
957 #endif
958 	initctx->ctrlreg[4] = /* CR4_PAE | */CR4_OSFXSR | CR4_OSXMMEXCPT;
959 
960 	/* Xen callbacks */
961 	initctx->event_callback_eip = (unsigned long)hypervisor_callback;
962 	initctx->event_callback_cs = GSEL(GCODE_SEL, SEL_KPL);
963 	initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
964 	initctx->failsafe_callback_cs = GSEL(GCODE_SEL, SEL_KPL);
965 
966 	return;
967 }
968 #endif /* __x86_64__ */
969 
970 int
971 mp_cpu_start(struct cpu_info *ci, vaddr_t target)
972 {
973 	int hyperror;
974 	struct vcpu_guest_context vcpuctx;
975 
976 	KASSERT(ci != NULL);
977 	KASSERT(ci != &cpu_info_primary);
978 	KASSERT(ci->ci_flags & CPUF_AP);
979 
980 #ifdef __x86_64__
981 	xen_init_amd64_vcpuctxt(ci, &vcpuctx, (void (*)(struct cpu_info *))target);
982 #else
983 	xen_init_i386_vcpuctxt(ci, &vcpuctx, (void (*)(struct cpu_info *))target);
984 #endif
985 
986 	/* Initialise the given vcpu to execute cpu_hatch(ci); */
987 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_initialise, ci->ci_cpuid, &vcpuctx))) {
988 		aprint_error(": context initialisation failed. errno = %d\n", hyperror);
989 		return hyperror;
990 	}
991 
992 	/* Start it up */
993 
994 	/* First bring it down */
995 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL))) {
996 		aprint_error(": VCPUOP_down hypervisor command failed. errno = %d\n", hyperror);
997 		return hyperror;
998 	}
999 
1000 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_up, ci->ci_cpuid, NULL))) {
1001 		aprint_error(": VCPUOP_up hypervisor command failed. errno = %d\n", hyperror);
1002 		return hyperror;
1003 	}
1004 
1005 	if (!vcpu_is_up(ci)) {
1006 		aprint_error(": did not come up\n");
1007 		return -1;
1008 	}
1009 
1010 	return 0;
1011 }
1012 
1013 void
1014 mp_cpu_start_cleanup(struct cpu_info *ci)
1015 {
1016 	if (vcpu_is_up(ci)) {
1017 		aprint_debug_dev(ci->ci_dev, "is started.\n");
1018 	} else {
1019 		aprint_error_dev(ci->ci_dev, "did not start up.\n");
1020 	}
1021 }
1022 
1023 void
1024 cpu_init_msrs(struct cpu_info *ci, bool full)
1025 {
1026 #ifdef __x86_64__
1027 	if (full) {
1028 		HYPERVISOR_set_segment_base(SEGBASE_FS, 0);
1029 		HYPERVISOR_set_segment_base(SEGBASE_GS_KERNEL, (uint64_t)ci);
1030 		HYPERVISOR_set_segment_base(SEGBASE_GS_USER, 0);
1031 	}
1032 #endif
1033 
1034 	if (cpu_feature[2] & CPUID_NOX)
1035 		wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NXE);
1036 }
1037 
1038 void
1039 cpu_offline_md(void)
1040 {
1041 	int s;
1042 
1043 	s = splhigh();
1044 	fpusave_cpu(true);
1045 	splx(s);
1046 }
1047 
1048 void
1049 cpu_get_tsc_freq(struct cpu_info *ci)
1050 {
1051 	uint32_t vcpu_tversion;
1052 	const volatile vcpu_time_info_t *tinfo = &ci->ci_vcpu->time;
1053 
1054 	vcpu_tversion = tinfo->version;
1055 	while (tinfo->version == vcpu_tversion); /* Wait for a time update. XXX: timeout ? */
1056 
1057 	uint64_t freq = 1000000000ULL << 32;
1058 	freq = freq / (uint64_t)tinfo->tsc_to_system_mul;
1059 	if (tinfo->tsc_shift < 0)
1060 		freq = freq << -tinfo->tsc_shift;
1061 	else
1062 		freq = freq >> tinfo->tsc_shift;
1063 	ci->ci_data.cpu_cc_freq = freq;
1064 }
1065 
1066 void
1067 x86_cpu_idle_xen(void)
1068 {
1069 	struct cpu_info *ci = curcpu();
1070 
1071 	KASSERT(ci->ci_ilevel == IPL_NONE);
1072 
1073 	x86_disable_intr();
1074 	if (!__predict_false(ci->ci_want_resched)) {
1075 		idle_block();
1076 	} else {
1077 		x86_enable_intr();
1078 	}
1079 }
1080 
1081 /*
1082  * Loads pmap for the current CPU.
1083  */
1084 void
1085 cpu_load_pmap(struct pmap *pmap, struct pmap *oldpmap)
1086 {
1087 	KASSERT(pmap != pmap_kernel());
1088 
1089 #if defined(__x86_64__) || defined(PAE)
1090 	struct cpu_info *ci = curcpu();
1091 	cpuid_t cid = cpu_index(ci);
1092 
1093 	mutex_enter(&ci->ci_kpm_mtx);
1094 	/* make new pmap visible to xen_kpm_sync() */
1095 	kcpuset_atomic_set(pmap->pm_xen_ptp_cpus, cid);
1096 #endif
1097 
1098 #ifdef i386
1099 #ifdef PAE
1100 	{
1101 		int i;
1102 		paddr_t l3_pd = xpmap_ptom_masked(ci->ci_pae_l3_pdirpa);
1103 		/* don't update the kernel L3 slot */
1104 		for (i = 0 ; i < PDP_SIZE - 1; i++) {
1105 			xpq_queue_pte_update(l3_pd + i * sizeof(pd_entry_t),
1106 			    xpmap_ptom(pmap->pm_pdirpa[i]) | PG_V);
1107 		}
1108 		tlbflush();
1109 	}
1110 #else /* PAE */
1111 	lcr3(pmap_pdirpa(pmap, 0));
1112 #endif /* PAE */
1113 #endif /* i386 */
1114 
1115 #ifdef __x86_64__
1116 	{
1117 		int i;
1118 		pd_entry_t *new_pgd;
1119 		paddr_t l4_pd_ma;
1120 
1121 		l4_pd_ma = xpmap_ptom_masked(ci->ci_kpm_pdirpa);
1122 
1123 		/*
1124 		 * Map user space address in kernel space and load
1125 		 * user cr3
1126 		 */
1127 		new_pgd = pmap->pm_pdir;
1128 		KASSERT(pmap == ci->ci_pmap);
1129 
1130 		/* Copy user pmap L4 PDEs (in user addr. range) to per-cpu L4 */
1131 		for (i = 0; i < PDIR_SLOT_PTE; i++) {
1132 			KASSERT(pmap != pmap_kernel() || new_pgd[i] == 0);
1133 			if (ci->ci_kpm_pdir[i] != new_pgd[i]) {
1134 				xpq_queue_pte_update(
1135 				    l4_pd_ma + i * sizeof(pd_entry_t),
1136 				    new_pgd[i]);
1137 			}
1138 		}
1139 
1140 		xen_set_user_pgd(pmap_pdirpa(pmap, 0));
1141 		ci->ci_xen_current_user_pgd = pmap_pdirpa(pmap, 0);
1142 
1143 		tlbflush();
1144 	}
1145 #endif /* __x86_64__ */
1146 
1147 #if defined(__x86_64__) || defined(PAE)
1148 	/* old pmap no longer visible to xen_kpm_sync() */
1149 	if (oldpmap != pmap_kernel()) {
1150 		kcpuset_atomic_clear(oldpmap->pm_xen_ptp_cpus, cid);
1151 	}
1152 	mutex_exit(&ci->ci_kpm_mtx);
1153 #endif
1154 }
1155 
1156 /*
1157  * pmap_cpu_init_late: perform late per-CPU initialization.
1158  *
1159  * Short note about percpu PDIR pages. Both the PAE and __x86_64__ architectures
1160  * have per-cpu PDIR tables, for two different reasons:
1161  *  - on PAE, this is to get around Xen's pagetable setup constraints (multiple
1162  *    L3[3]s cannot point to the same L2 - Xen will refuse to pin a table set up
1163  *    this way).
1164  *  - on __x86_64__, this is for multiple CPUs to map in different user pmaps
1165  *    (see cpu_load_pmap()).
1166  *
1167  * What this means for us is that the PDIR of the pmap_kernel() is considered
1168  * to be a canonical "SHADOW" PDIR with the following properties:
1169  *  - its recursive mapping points to itself
1170  *  - per-cpu recursive mappings point to themselves on __x86_64__
1171  *  - per-cpu L4 pages' kernel entries are expected to be in sync with
1172  *    the shadow
1173  */
1174 
1175 void
1176 pmap_cpu_init_late(struct cpu_info *ci)
1177 {
1178 #if defined(PAE) || defined(__x86_64__)
1179 	/*
1180 	 * The BP has already its own PD page allocated during early
1181 	 * MD startup.
1182 	 */
1183 
1184 #if defined(__x86_64__)
1185 	/* Setup per-cpu normal_pdes */
1186 	int i;
1187 	extern pd_entry_t * const normal_pdes[];
1188 	for (i = 0;i < PTP_LEVELS - 1;i++) {
1189 		ci->ci_normal_pdes[i] = normal_pdes[i];
1190 	}
1191 #endif /* __x86_64__ */
1192 
1193 	if (ci == &cpu_info_primary)
1194 		return;
1195 
1196 	KASSERT(ci != NULL);
1197 
1198 #if defined(PAE)
1199 	cpu_alloc_l3_page(ci);
1200 	KASSERT(ci->ci_pae_l3_pdirpa != 0);
1201 
1202 	/* Initialise L2 entries 0 - 2: Point them to pmap_kernel() */
1203 	int i;
1204 	for (i = 0 ; i < PDP_SIZE - 1; i++) {
1205 		ci->ci_pae_l3_pdir[i] =
1206 		    xpmap_ptom_masked(pmap_kernel()->pm_pdirpa[i]) | PG_V;
1207 	}
1208 #endif /* PAE */
1209 
1210 	ci->ci_kpm_pdir = (pd_entry_t *)uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
1211 	    UVM_KMF_WIRED | UVM_KMF_ZERO | UVM_KMF_NOWAIT);
1212 
1213 	if (ci->ci_kpm_pdir == NULL) {
1214 		panic("%s: failed to allocate L4 per-cpu PD for CPU %d\n",
1215 		    __func__, cpu_index(ci));
1216 	}
1217 	ci->ci_kpm_pdirpa = vtophys((vaddr_t)ci->ci_kpm_pdir);
1218 	KASSERT(ci->ci_kpm_pdirpa != 0);
1219 
1220 #if defined(__x86_64__)
1221 	/*
1222 	 * Copy over the pmap_kernel() shadow L4 entries
1223 	 */
1224 
1225 	memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir, PAGE_SIZE);
1226 
1227 	/* Recursive kernel mapping */
1228 	ci->ci_kpm_pdir[PDIR_SLOT_PTE] = xpmap_ptom_masked(ci->ci_kpm_pdirpa)
1229 	    | PG_k | PG_V;
1230 #elif defined(PAE)
1231 	/* Copy over the pmap_kernel() shadow L2 entries that map the kernel */
1232 	memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir + PDIR_SLOT_KERN,
1233 	    nkptp[PTP_LEVELS - 1] * sizeof(pd_entry_t));
1234 #endif /* __x86_64__ else PAE */
1235 
1236 	/* Xen wants a RO pdir. */
1237 	pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_kpm_pdir,
1238 	    (vaddr_t)ci->ci_kpm_pdir + PAGE_SIZE, VM_PROT_READ);
1239 	pmap_update(pmap_kernel());
1240 #if defined(PAE)
1241 	/*
1242 	 * Initialize L3 entry 3. This mapping is shared across all pmaps and is
1243 	 * static, ie: loading a new pmap will not update this entry.
1244 	 */
1245 	ci->ci_pae_l3_pdir[3] = xpmap_ptom_masked(ci->ci_kpm_pdirpa) | PG_k | PG_V;
1246 
1247 	/* Xen wants a RO L3. */
1248 	pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_pae_l3_pdir,
1249 	    (vaddr_t)ci->ci_pae_l3_pdir + PAGE_SIZE, VM_PROT_READ);
1250 	pmap_update(pmap_kernel());
1251 
1252 	xpq_queue_pin_l3_table(xpmap_ptom_masked(ci->ci_pae_l3_pdirpa));
1253 
1254 #elif defined(__x86_64__)
1255 	xpq_queue_pin_l4_table(xpmap_ptom_masked(ci->ci_kpm_pdirpa));
1256 #endif /* PAE , __x86_64__ */
1257 #endif /* defined(PAE) || defined(__x86_64__) */
1258 }
1259 
1260 /*
1261  * Notify all other cpus to halt.
1262  */
1263 
1264 void
1265 cpu_broadcast_halt(void)
1266 {
1267 	xen_broadcast_ipi(XEN_IPI_HALT);
1268 }
1269 
1270 /*
1271  * Send a dummy ipi to a cpu.
1272  */
1273 
1274 void
1275 cpu_kick(struct cpu_info *ci)
1276 {
1277 	(void)xen_send_ipi(ci, XEN_IPI_KICK);
1278 }
1279