xref: /netbsd-src/sys/arch/xen/x86/cpu.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /*	$NetBSD: cpu.c,v 1.129 2019/03/09 08:42:25 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 1.129 2019/03/09 08:42:25 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/cpu.h>
93 #include <machine/cpufunc.h>
94 #include <machine/cpuvar.h>
95 #include <machine/pmap.h>
96 #include <machine/vmparam.h>
97 #include <machine/mpbiosvar.h>
98 #include <machine/pcb.h>
99 #include <machine/specialreg.h>
100 #include <machine/segments.h>
101 #include <machine/gdt.h>
102 #include <machine/mtrr.h>
103 #include <machine/pio.h>
104 
105 #include <x86/fpu.h>
106 
107 #include <xen/xen.h>
108 #include <xen/include/public/vcpu.h>
109 #include <xen/vcpuvar.h>
110 
111 #if NLAPIC > 0
112 #include <machine/apicvar.h>
113 #include <machine/i82489reg.h>
114 #include <machine/i82489var.h>
115 #endif
116 
117 #include <dev/ic/mc146818reg.h>
118 #include <dev/isa/isareg.h>
119 
120 static int	cpu_match(device_t, cfdata_t, void *);
121 static void	cpu_attach(device_t, device_t, void *);
122 static void	cpu_defer(device_t);
123 static int	cpu_rescan(device_t, const char *, const int *);
124 static void	cpu_childdetached(device_t, device_t);
125 static int	vcpu_match(device_t, cfdata_t, void *);
126 static void	vcpu_attach(device_t, device_t, void *);
127 static void	cpu_attach_common(device_t, device_t, void *);
128 void		cpu_offline_md(void);
129 
130 struct cpu_softc {
131 	device_t sc_dev;		/* device tree glue */
132 	struct cpu_info *sc_info;	/* pointer to CPU info */
133 	bool sc_wasonline;
134 };
135 
136 int mp_cpu_start(struct cpu_info *, vaddr_t);
137 void mp_cpu_start_cleanup(struct cpu_info *);
138 const struct cpu_functions mp_cpu_funcs = { mp_cpu_start, NULL,
139 				      mp_cpu_start_cleanup };
140 
141 CFATTACH_DECL2_NEW(cpu, sizeof(struct cpu_softc),
142     cpu_match, cpu_attach, NULL, NULL, cpu_rescan, cpu_childdetached);
143 
144 CFATTACH_DECL_NEW(vcpu, sizeof(struct cpu_softc),
145     vcpu_match, vcpu_attach, NULL, NULL);
146 
147 /*
148  * Statically-allocated CPU info for the primary CPU (or the only
149  * CPU, on uniprocessors).  The CPU info list is initialized to
150  * point at it.
151  */
152 struct cpu_info cpu_info_primary __aligned(CACHE_LINE_SIZE) = {
153 	.ci_dev = 0,
154 	.ci_self = &cpu_info_primary,
155 	.ci_idepth = -1,
156 	.ci_curlwp = &lwp0,
157 	.ci_curldt = -1,
158 };
159 struct cpu_info phycpu_info_primary __aligned(CACHE_LINE_SIZE) = {
160 	.ci_dev = 0,
161 	.ci_self = &phycpu_info_primary,
162 };
163 
164 struct cpu_info *cpu_info_list = &cpu_info_primary;
165 struct cpu_info *phycpu_info_list = &phycpu_info_primary;
166 
167 uint32_t cpu_feature[7] __read_mostly; /* X86 CPUID feature bits
168 			  *	[0] basic features %edx
169 			  *	[1] basic features %ecx
170 			  *	[2] extended features %edx
171 			  *	[3] extended features %ecx
172 			  *	[4] VIA padlock features
173 			  *	[5] structured extended features cpuid.7:%ebx
174 			  *	[6] structured extended features cpuid.7:%ecx
175 			  */
176 
177 bool x86_mp_online;
178 paddr_t mp_trampoline_paddr = MP_TRAMPOLINE;
179 
180 #if defined(MULTIPROCESSOR)
181 void    	cpu_hatch(void *);
182 static void    	cpu_boot_secondary(struct cpu_info *ci);
183 static void    	cpu_start_secondary(struct cpu_info *ci);
184 #endif	/* MULTIPROCESSOR */
185 
186 static int
187 cpu_match(device_t parent, cfdata_t match, void *aux)
188 {
189 
190 	return 1;
191 }
192 
193 static void
194 cpu_attach(device_t parent, device_t self, void *aux)
195 {
196 	struct cpu_softc *sc = device_private(self);
197 	struct cpu_attach_args *caa = aux;
198 	struct cpu_info *ci;
199 	uintptr_t ptr;
200 	static int nphycpu = 0;
201 
202 	sc->sc_dev = self;
203 
204 	/*
205 	 * If we're an Application Processor, allocate a cpu_info
206 	 * If we're the first attached CPU use the primary cpu_info,
207 	 * otherwise allocate a new one
208 	 */
209 	aprint_naive("\n");
210 	aprint_normal("\n");
211 	if (nphycpu > 0) {
212 		struct cpu_info *tmp;
213 		ptr = (uintptr_t)kmem_zalloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
214 		    KM_SLEEP);
215 		ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
216 		ci->ci_curldt = -1;
217 
218 		tmp = phycpu_info_list;
219 		while (tmp->ci_next)
220 			tmp = tmp->ci_next;
221 
222 		tmp->ci_next = ci;
223 	} else {
224 		ci = &phycpu_info_primary;
225 	}
226 
227 	ci->ci_self = ci;
228 	sc->sc_info = ci;
229 
230 	ci->ci_dev = self;
231 	ci->ci_acpiid = caa->cpu_id;
232 	ci->ci_cpuid = caa->cpu_number;
233 	ci->ci_vcpu = NULL;
234 	ci->ci_index = nphycpu++;
235 
236 	if (!pmf_device_register(self, NULL, NULL))
237 		aprint_error_dev(self, "couldn't establish power handler\n");
238 
239 	(void)config_defer(self, cpu_defer);
240 }
241 
242 static void
243 cpu_defer(device_t self)
244 {
245 	cpu_rescan(self, NULL, NULL);
246 }
247 
248 static int
249 cpu_rescan(device_t self, const char *ifattr, const int *locators)
250 {
251 	struct cpu_softc *sc = device_private(self);
252 	struct cpufeature_attach_args cfaa;
253 	struct cpu_info *ci = sc->sc_info;
254 
255 	memset(&cfaa, 0, sizeof(cfaa));
256 	cfaa.ci = ci;
257 
258 	if (ifattr_match(ifattr, "cpufeaturebus")) {
259 
260 		if (ci->ci_frequency == NULL) {
261 			cfaa.name = "frequency";
262 			ci->ci_frequency = config_found_ia(self,
263 			    "cpufeaturebus", &cfaa, NULL);
264 		}
265 	}
266 
267 	return 0;
268 }
269 
270 static void
271 cpu_childdetached(device_t self, device_t child)
272 {
273 	struct cpu_softc *sc = device_private(self);
274 	struct cpu_info *ci = sc->sc_info;
275 
276 	if (ci->ci_frequency == child)
277 		ci->ci_frequency = NULL;
278 }
279 
280 static int
281 vcpu_match(device_t parent, cfdata_t match, void *aux)
282 {
283 	struct vcpu_attach_args *vcaa = aux;
284 	struct vcpu_runstate_info vcr;
285 	int error;
286 
287 	if (strcmp(vcaa->vcaa_name, match->cf_name) == 0) {
288 		error = HYPERVISOR_vcpu_op(VCPUOP_get_runstate_info,
289 		    vcaa->vcaa_caa.cpu_number, &vcr);
290 		switch (error) {
291 		case 0:
292 			return 1;
293 		case -ENOENT:
294 			return 0;
295 		default:
296 			panic("Unknown hypervisor error %d returned on vcpu runstate probe\n", error);
297 		}
298 	}
299 
300 	return 0;
301 }
302 
303 static void
304 vcpu_attach(device_t parent, device_t self, void *aux)
305 {
306 	struct vcpu_attach_args *vcaa = aux;
307 
308 	KASSERT(vcaa->vcaa_caa.cpu_func == NULL);
309 	vcaa->vcaa_caa.cpu_func = &mp_cpu_funcs;
310 	cpu_attach_common(parent, self, &vcaa->vcaa_caa);
311 
312 	if (!pmf_device_register(self, NULL, NULL))
313 		aprint_error_dev(self, "couldn't establish power handler\n");
314 }
315 
316 static int
317 vcpu_is_up(struct cpu_info *ci)
318 {
319 	KASSERT(ci != NULL);
320 	return HYPERVISOR_vcpu_op(VCPUOP_is_up, ci->ci_cpuid, NULL);
321 }
322 
323 static void
324 cpu_vm_init(struct cpu_info *ci)
325 {
326 	int ncolors = 2, i;
327 
328 	for (i = CAI_ICACHE; i <= CAI_L2CACHE; i++) {
329 		struct x86_cache_info *cai;
330 		int tcolors;
331 
332 		cai = &ci->ci_cinfo[i];
333 
334 		tcolors = atop(cai->cai_totalsize);
335 		switch (cai->cai_associativity) {
336 		case 0xff:
337 			tcolors = 1; /* fully associative */
338 			break;
339 		case 0:
340 		case 1:
341 			break;
342 		default:
343 			tcolors /= cai->cai_associativity;
344 		}
345 		ncolors = uimax(ncolors, tcolors);
346 	}
347 
348 	/*
349 	 * Knowing the size of the largest cache on this CPU, potentially
350 	 * re-color our pages.
351 	 */
352 	aprint_debug_dev(ci->ci_dev, "%d page colors\n", ncolors);
353 	uvm_page_recolor(ncolors);
354 	pmap_tlb_cpu_init(ci);
355 #ifndef __HAVE_DIRECT_MAP
356 	pmap_vpage_cpu_init(ci);
357 #endif
358 }
359 
360 static void
361 cpu_attach_common(device_t parent, device_t self, void *aux)
362 {
363 	struct cpu_softc *sc = device_private(self);
364 	struct cpu_attach_args *caa = aux;
365 	struct cpu_info *ci;
366 	uintptr_t ptr;
367 	int cpunum = caa->cpu_number;
368 	static bool again = false;
369 
370 	sc->sc_dev = self;
371 
372 	/*
373 	 * If we're an Application Processor, allocate a cpu_info
374 	 * structure, otherwise use the primary's.
375 	 */
376 	if (caa->cpu_role == CPU_ROLE_AP) {
377 		aprint_naive(": Application Processor\n");
378 		ptr = (uintptr_t)kmem_alloc(sizeof(*ci) + CACHE_LINE_SIZE - 1,
379 		    KM_SLEEP);
380 		ci = (struct cpu_info *)roundup2(ptr, CACHE_LINE_SIZE);
381 		memset(ci, 0, sizeof(*ci));
382 		cpu_init_tss(ci);
383 	} else {
384 		aprint_naive(": %s Processor\n",
385 		    caa->cpu_role == CPU_ROLE_SP ? "Single" : "Boot");
386 		ci = &cpu_info_primary;
387 	}
388 
389 	ci->ci_self = ci;
390 	sc->sc_info = ci;
391 	ci->ci_dev = self;
392 	ci->ci_cpuid = cpunum;
393 
394 	KASSERT(HYPERVISOR_shared_info != NULL);
395 	KASSERT(cpunum < XEN_LEGACY_MAX_VCPUS);
396 	ci->ci_vcpu = &HYPERVISOR_shared_info->vcpu_info[cpunum];
397 
398 	KASSERT(ci->ci_func == 0);
399 	ci->ci_func = caa->cpu_func;
400 	aprint_normal("\n");
401 
402 	/* Must be called before mi_cpu_attach(). */
403 	cpu_vm_init(ci);
404 
405 	if (caa->cpu_role == CPU_ROLE_AP) {
406 		int error;
407 
408 		error = mi_cpu_attach(ci);
409 
410 		KASSERT(ci->ci_data.cpu_idlelwp != NULL);
411 		if (error != 0) {
412 			aprint_error_dev(self,
413 			    "mi_cpu_attach failed with %d\n", error);
414 			return;
415 		}
416 
417 	} else {
418 		KASSERT(ci->ci_data.cpu_idlelwp != NULL);
419 	}
420 
421 	KASSERT(ci->ci_cpuid == ci->ci_index);
422 #ifdef __x86_64__
423 	/* No user PGD mapped for this CPU yet */
424 	ci->ci_xen_current_user_pgd = 0;
425 #endif
426 	mutex_init(&ci->ci_kpm_mtx, MUTEX_DEFAULT, IPL_VM);
427 	pmap_reference(pmap_kernel());
428 	ci->ci_pmap = pmap_kernel();
429 	ci->ci_tlbstate = TLBSTATE_STALE;
430 
431 	/*
432 	 * Boot processor may not be attached first, but the below
433 	 * must be done to allow booting other processors.
434 	 */
435 	if (!again) {
436 		atomic_or_32(&ci->ci_flags, CPUF_PRESENT | CPUF_PRIMARY);
437 		/* Basic init. */
438 		cpu_intr_init(ci);
439 		cpu_get_tsc_freq(ci);
440 		cpu_init(ci);
441 		pmap_cpu_init_late(ci);
442 
443 		/* Every processor needs to init its own ipi h/w (similar to lapic) */
444 		xen_ipi_init();
445 
446 		/* Make sure DELAY() is initialized. */
447 		DELAY(1);
448 		again = true;
449 	}
450 
451 	/* further PCB init done later. */
452 
453 	switch (caa->cpu_role) {
454 	case CPU_ROLE_SP:
455 		atomic_or_32(&ci->ci_flags, CPUF_SP);
456 		cpu_identify(ci);
457 		x86_cpu_idle_init();
458 		break;
459 
460 	case CPU_ROLE_BP:
461 		atomic_or_32(&ci->ci_flags, CPUF_BSP);
462 		cpu_identify(ci);
463 		x86_cpu_idle_init();
464 		break;
465 
466 	case CPU_ROLE_AP:
467 		atomic_or_32(&ci->ci_flags, CPUF_AP);
468 
469 		/*
470 		 * report on an AP
471 		 */
472 
473 #if defined(MULTIPROCESSOR)
474 		/* interrupt handler stack */
475 		cpu_intr_init(ci);
476 
477 		/* Setup per-cpu memory for gdt */
478 		gdt_alloc_cpu(ci);
479 
480 		pmap_cpu_init_late(ci);
481 		cpu_start_secondary(ci);
482 
483 		if (ci->ci_flags & CPUF_PRESENT) {
484 			struct cpu_info *tmp;
485 
486 			cpu_identify(ci);
487 			tmp = cpu_info_list;
488 			while (tmp->ci_next)
489 				tmp = tmp->ci_next;
490 
491 			tmp->ci_next = ci;
492 		}
493 #else
494 		aprint_error_dev(ci->ci_dev, "not started\n");
495 #endif
496 		break;
497 
498 	default:
499 		panic("unknown processor type??\n");
500 	}
501 
502 #ifdef MPVERBOSE
503 	if (mp_verbose) {
504 		struct lwp *l = ci->ci_data.cpu_idlelwp;
505 		struct pcb *pcb = lwp_getpcb(l);
506 
507 		aprint_verbose_dev(self,
508 		    "idle lwp at %p, idle sp at 0x%p\n",
509 		    l,
510 #ifdef i386
511 		    (void *)pcb->pcb_esp
512 #else
513 		    (void *)pcb->pcb_rsp
514 #endif
515 		);
516 
517 	}
518 #endif /* MPVERBOSE */
519 }
520 
521 /*
522  * Initialize the processor appropriately.
523  */
524 
525 void
526 cpu_init(struct cpu_info *ci)
527 {
528 	uint32_t cr4 = 0;
529 
530 	/*
531 	 * If we have FXSAVE/FXRESTOR, use them.
532 	 */
533 	if (cpu_feature[0] & CPUID_FXSR) {
534 		cr4 |= CR4_OSFXSR;
535 
536 		/*
537 		 * If we have SSE/SSE2, enable XMM exceptions.
538 		 */
539 		if (cpu_feature[0] & (CPUID_SSE|CPUID_SSE2))
540 			cr4 |= CR4_OSXMMEXCPT;
541 	}
542 
543 	/* If xsave is supported, enable it */
544 	if (cpu_feature[1] & CPUID2_XSAVE && x86_fpu_save >= FPU_SAVE_XSAVE)
545 		cr4 |= CR4_OSXSAVE;
546 
547 	if (cr4) {
548 		cr4 |= rcr4();
549 		lcr4(cr4);
550 	}
551 
552 	if (x86_fpu_save >= FPU_SAVE_FXSAVE) {
553 		fpuinit_mxcsr_mask();
554 	}
555 
556 	/*
557 	 * Changing CR4 register may change cpuid values. For example, setting
558 	 * CR4_OSXSAVE sets CPUID2_OSXSAVE. The CPUID2_OSXSAVE is in
559 	 * ci_feat_val[1], so update it.
560 	 * XXX Other than ci_feat_val[1] might be changed.
561 	 */
562 	if (cpuid_level >= 1) {
563 		u_int descs[4];
564 
565 		x86_cpuid(1, descs);
566 		ci->ci_feat_val[1] = descs[2];
567 	}
568 
569 	/* If xsave is enabled, enable all fpu features */
570 	if (cr4 & CR4_OSXSAVE) {
571 		wrxcr(0, x86_xsave_features & XCR0_FPU);
572 	}
573 
574 	atomic_or_32(&ci->ci_flags, CPUF_RUNNING);
575 }
576 
577 
578 #ifdef MULTIPROCESSOR
579 
580 void
581 cpu_boot_secondary_processors(void)
582 {
583 	struct cpu_info *ci;
584 	kcpuset_t *cpus;
585 	u_long i;
586 
587 	kcpuset_create(&cpus, true);
588 	kcpuset_set(cpus, cpu_index(curcpu()));
589 	for (i = 0; i < maxcpus; i++) {
590 		ci = cpu_lookup(i);
591 		if (ci == NULL)
592 			continue;
593 		if (ci->ci_data.cpu_idlelwp == NULL)
594 			continue;
595 		if ((ci->ci_flags & CPUF_PRESENT) == 0)
596 			continue;
597 		if (ci->ci_flags & (CPUF_BSP|CPUF_SP|CPUF_PRIMARY))
598 			continue;
599 		cpu_boot_secondary(ci);
600 		kcpuset_set(cpus, cpu_index(ci));
601 	}
602 	while (!kcpuset_match(cpus, kcpuset_running))
603 		;
604 	kcpuset_destroy(cpus);
605 
606 	x86_mp_online = true;
607 }
608 
609 static void
610 cpu_init_idle_lwp(struct cpu_info *ci)
611 {
612 	struct lwp *l = ci->ci_data.cpu_idlelwp;
613 	struct pcb *pcb = lwp_getpcb(l);
614 
615 	pcb->pcb_cr0 = rcr0();
616 }
617 
618 void
619 cpu_init_idle_lwps(void)
620 {
621 	struct cpu_info *ci;
622 	u_long i;
623 
624 	for (i = 0; i < maxcpus; i++) {
625 		ci = cpu_lookup(i);
626 		if (ci == NULL)
627 			continue;
628 		if (ci->ci_data.cpu_idlelwp == NULL)
629 			continue;
630 		if ((ci->ci_flags & CPUF_PRESENT) == 0)
631 			continue;
632 		cpu_init_idle_lwp(ci);
633 	}
634 }
635 
636 static void
637 cpu_start_secondary(struct cpu_info *ci)
638 {
639 	int i;
640 
641 	aprint_debug_dev(ci->ci_dev, "starting\n");
642 
643 	ci->ci_curlwp = ci->ci_data.cpu_idlelwp;
644 
645 	if (CPU_STARTUP(ci, (vaddr_t) cpu_hatch) != 0) {
646 		return;
647 	}
648 
649 	/*
650 	 * wait for it to become ready
651 	 */
652 	for (i = 100000; (!(ci->ci_flags & CPUF_PRESENT)) && i > 0; i--) {
653 		delay(10);
654 	}
655 	if ((ci->ci_flags & CPUF_PRESENT) == 0) {
656 		aprint_error_dev(ci->ci_dev, "failed to become ready\n");
657 #if defined(MPDEBUG) && defined(DDB)
658 		printf("dropping into debugger; continue from here to resume boot\n");
659 		Debugger();
660 #endif
661 	}
662 
663 	CPU_START_CLEANUP(ci);
664 }
665 
666 void
667 cpu_boot_secondary(struct cpu_info *ci)
668 {
669 	int i;
670 	atomic_or_32(&ci->ci_flags, CPUF_GO);
671 	for (i = 100000; (!(ci->ci_flags & CPUF_RUNNING)) && i > 0; i--) {
672 		delay(10);
673 	}
674 	if ((ci->ci_flags & CPUF_RUNNING) == 0) {
675 		aprint_error_dev(ci->ci_dev, "CPU failed to start\n");
676 #if defined(MPDEBUG) && defined(DDB)
677 		printf("dropping into debugger; continue from here to resume boot\n");
678 		Debugger();
679 #endif
680 	}
681 }
682 
683 /*
684  * APs end up here immediately after initialisation and VCPUOP_up in
685  * mp_cpu_start().
686  * At this point, we are running in the idle pcb/idle stack of the new
687  * CPU.  This function jumps to the idle loop and starts looking for
688  * work.
689  */
690 extern void x86_64_tls_switch(struct lwp *);
691 void
692 cpu_hatch(void *v)
693 {
694 	struct cpu_info *ci = (struct cpu_info *)v;
695 	struct pcb *pcb;
696 	int s, i;
697 
698 	/* Setup TLS and kernel GS/FS */
699 	cpu_init_msrs(ci, true);
700 	cpu_init_idt();
701 	gdt_init_cpu(ci);
702 
703 	cpu_probe(ci);
704 
705 	atomic_or_32(&ci->ci_flags, CPUF_PRESENT);
706 
707 	while ((ci->ci_flags & CPUF_GO) == 0) {
708 		/* Don't use delay, boot CPU may be patching the text. */
709 		for (i = 10000; i != 0; i--)
710 			x86_pause();
711 	}
712 
713 	/* Because the text may have been patched in x86_patch(). */
714 	x86_flush();
715 	tlbflushg();
716 
717 	KASSERT((ci->ci_flags & CPUF_RUNNING) == 0);
718 
719 	pcb = lwp_getpcb(curlwp);
720 	pcb->pcb_cr3 = pmap_pdirpa(pmap_kernel(), 0);
721 	pcb = lwp_getpcb(ci->ci_data.cpu_idlelwp);
722 
723 	xen_ipi_init();
724 
725 	xen_initclocks();
726 
727 #ifdef __x86_64__
728 	fpuinit(ci);
729 #endif
730 
731 	lldt(GSEL(GLDT_SEL, SEL_KPL));
732 
733 	cpu_init(ci);
734 	cpu_get_tsc_freq(ci);
735 
736 	s = splhigh();
737 	x86_enable_intr();
738 	splx(s);
739 
740 	aprint_debug_dev(ci->ci_dev, "running\n");
741 
742 	cpu_switchto(NULL, ci->ci_data.cpu_idlelwp, true);
743 
744 	idle_loop(NULL);
745 	KASSERT(false);
746 }
747 
748 #if defined(DDB)
749 
750 #include <ddb/db_output.h>
751 #include <machine/db_machdep.h>
752 
753 /*
754  * Dump CPU information from ddb.
755  */
756 void
757 cpu_debug_dump(void)
758 {
759 	struct cpu_info *ci;
760 	CPU_INFO_ITERATOR cii;
761 
762 	db_printf("addr		dev	id	flags	ipis	curlwp 		fpcurlwp\n");
763 	for (CPU_INFO_FOREACH(cii, ci)) {
764 		db_printf("%p	%s	%ld	%x	%x	%10p	%10p\n",
765 		    ci,
766 		    ci->ci_dev == NULL ? "BOOT" : device_xname(ci->ci_dev),
767 		    (long)ci->ci_cpuid,
768 		    ci->ci_flags, ci->ci_ipis,
769 		    ci->ci_curlwp,
770 		    ci->ci_fpcurlwp);
771 	}
772 }
773 #endif /* DDB */
774 
775 #endif /* MULTIPROCESSOR */
776 
777 extern void hypervisor_callback(void);
778 extern void failsafe_callback(void);
779 #ifdef __x86_64__
780 typedef void (vector)(void);
781 extern vector Xsyscall, Xsyscall32;
782 #endif
783 
784 /*
785  * Setup the "trampoline". On Xen, we setup nearly all cpu context
786  * outside a trampoline, so we prototype and call targetip like so:
787  * void targetip(struct cpu_info *);
788  */
789 
790 static void
791 gdt_prepframes(paddr_t *frames, vaddr_t base, uint32_t entries)
792 {
793 	int i;
794 	for (i = 0; i < entries; i++) {
795 		frames[i] = ((paddr_t)xpmap_ptetomach(
796 		    (pt_entry_t *)(base + (i << PAGE_SHIFT)))) >> PAGE_SHIFT;
797 
798 		/* Mark Read-only */
799 		pmap_pte_clearbits(kvtopte(base + (i << PAGE_SHIFT)),
800 		    PTE_W);
801 	}
802 }
803 
804 #ifdef __x86_64__
805 extern char *ldtstore;
806 
807 static void
808 xen_init_amd64_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
809     void targetrip(struct cpu_info *))
810 {
811 	/* page frames to point at GDT */
812 	extern int gdt_size;
813 	paddr_t frames[16];
814 	psize_t gdt_ents;
815 
816 	struct lwp *l;
817 	struct pcb *pcb;
818 
819 	volatile struct vcpu_info *vci;
820 
821 	KASSERT(ci != NULL);
822 	KASSERT(ci != &cpu_info_primary);
823 	KASSERT(initctx != NULL);
824 	KASSERT(targetrip != NULL);
825 
826 	memset(initctx, 0, sizeof(*initctx));
827 
828 	gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
829 	KASSERT(gdt_ents <= 16);
830 
831 	gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);
832 
833 	/* Initialise the vcpu context: We use idle_loop()'s pcb context. */
834 
835 	l = ci->ci_data.cpu_idlelwp;
836 
837 	KASSERT(l != NULL);
838 	pcb = lwp_getpcb(l);
839 	KASSERT(pcb != NULL);
840 
841 	/* resume with interrupts off */
842 	vci = ci->ci_vcpu;
843 	vci->evtchn_upcall_mask = 1;
844 	xen_mb();
845 
846 	/* resume in kernel-mode */
847 	initctx->flags = VGCF_in_kernel | VGCF_online;
848 
849 	/* Stack and entry points:
850 	 * We arrange for the stack frame for cpu_hatch() to
851 	 * appear as a callee frame of lwp_trampoline(). Being a
852 	 * leaf frame prevents trampling on any of the MD stack setup
853 	 * that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
854 	 */
855 
856 	initctx->user_regs.rdi = (uint64_t) ci; /* targetrip(ci); */
857 	initctx->user_regs.rip = (vaddr_t) targetrip;
858 
859 	initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);
860 
861 	initctx->user_regs.rflags = pcb->pcb_flags;
862 	initctx->user_regs.rsp = pcb->pcb_rsp;
863 
864 	/* Data segments */
865 	initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
866 	initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
867 	initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);
868 
869 	/* GDT */
870 	memcpy(initctx->gdt_frames, frames, sizeof(frames));
871 	initctx->gdt_ents = gdt_ents;
872 
873 	/* LDT */
874 	initctx->ldt_base = (unsigned long)ldtstore;
875 	initctx->ldt_ents = LDT_SIZE >> 3;
876 
877 	/* Kernel context state */
878 	initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
879 	initctx->kernel_sp = pcb->pcb_rsp0;
880 	initctx->ctrlreg[0] = pcb->pcb_cr0;
881 	initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
882 	initctx->ctrlreg[2] = (vaddr_t)targetrip;
883 	/*
884 	 * Use pmap_kernel() L4 PD directly, until we setup the
885 	 * per-cpu L4 PD in pmap_cpu_init_late()
886 	 */
887 	initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_kpm_pdirpa)));
888 	initctx->ctrlreg[4] = CR4_PAE | CR4_OSFXSR | CR4_OSXMMEXCPT;
889 
890 	/* Xen callbacks */
891 	initctx->event_callback_eip = (unsigned long)hypervisor_callback;
892 	initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
893 	initctx->syscall_callback_eip = (unsigned long)Xsyscall;
894 
895 	return;
896 }
897 #else /* i386 */
898 extern union descriptor *ldtstore;
899 extern void Xsyscall(void);
900 
901 static void
902 xen_init_i386_vcpuctxt(struct cpu_info *ci, struct vcpu_guest_context *initctx,
903     void targeteip(struct cpu_info *))
904 {
905 	/* page frames to point at GDT */
906 	extern int gdt_size;
907 	paddr_t frames[16];
908 	psize_t gdt_ents;
909 
910 	struct lwp *l;
911 	struct pcb *pcb;
912 
913 	volatile struct vcpu_info *vci;
914 
915 	KASSERT(ci != NULL);
916 	KASSERT(ci != &cpu_info_primary);
917 	KASSERT(initctx != NULL);
918 	KASSERT(targeteip != NULL);
919 
920 	memset(initctx, 0, sizeof(*initctx));
921 
922 	gdt_ents = roundup(gdt_size, PAGE_SIZE) >> PAGE_SHIFT;
923 	KASSERT(gdt_ents <= 16);
924 
925 	gdt_prepframes(frames, (vaddr_t)ci->ci_gdt, gdt_ents);
926 
927 	/*
928 	 * Initialise the vcpu context:
929 	 * We use this cpu's idle_loop() pcb context.
930 	 */
931 
932 	l = ci->ci_data.cpu_idlelwp;
933 
934 	KASSERT(l != NULL);
935 	pcb = lwp_getpcb(l);
936 	KASSERT(pcb != NULL);
937 
938 	/* resume with interrupts off */
939 	vci = ci->ci_vcpu;
940 	vci->evtchn_upcall_mask = 1;
941 	xen_mb();
942 
943 	/* resume in kernel-mode */
944 	initctx->flags = VGCF_in_kernel | VGCF_online;
945 
946 	/* Stack frame setup for cpu_hatch():
947 	 * We arrange for the stack frame for cpu_hatch() to
948 	 * appear as a callee frame of lwp_trampoline(). Being a
949 	 * leaf frame prevents trampling on any of the MD stack setup
950 	 * that x86/vm_machdep.c:cpu_lwp_fork() does for idle_loop()
951 	 */
952 
953 	initctx->user_regs.esp = pcb->pcb_esp - 4; /* Leave word for
954 						      arg1 */
955 	{
956 		/* targeteip(ci); */
957 		uint32_t *arg = (uint32_t *)initctx->user_regs.esp;
958 		arg[1] = (uint32_t)ci; /* arg1 */
959 	}
960 
961 	initctx->user_regs.eip = (vaddr_t)targeteip;
962 	initctx->user_regs.cs = GSEL(GCODE_SEL, SEL_KPL);
963 	initctx->user_regs.eflags |= pcb->pcb_iopl;
964 
965 	/* Data segments */
966 	initctx->user_regs.ss = GSEL(GDATA_SEL, SEL_KPL);
967 	initctx->user_regs.es = GSEL(GDATA_SEL, SEL_KPL);
968 	initctx->user_regs.ds = GSEL(GDATA_SEL, SEL_KPL);
969 	initctx->user_regs.fs = GSEL(GDATA_SEL, SEL_KPL);
970 
971 	/* GDT */
972 	memcpy(initctx->gdt_frames, frames, sizeof(frames));
973 	initctx->gdt_ents = gdt_ents;
974 
975 	/* LDT */
976 	initctx->ldt_base = (unsigned long)ldtstore;
977 	initctx->ldt_ents = NLDT;
978 
979 	/* Kernel context state */
980 	initctx->kernel_ss = GSEL(GDATA_SEL, SEL_KPL);
981 	initctx->kernel_sp = pcb->pcb_esp0;
982 	initctx->ctrlreg[0] = pcb->pcb_cr0;
983 	initctx->ctrlreg[1] = 0; /* "resuming" from kernel - no User cr3. */
984 	initctx->ctrlreg[2] = (vaddr_t)targeteip;
985 	initctx->ctrlreg[3] = xen_pfn_to_cr3(x86_btop(xpmap_ptom(ci->ci_pae_l3_pdirpa)));
986 	initctx->ctrlreg[4] = /* CR4_PAE | */CR4_OSFXSR | CR4_OSXMMEXCPT;
987 
988 	/* Xen callbacks */
989 	initctx->event_callback_eip = (unsigned long)hypervisor_callback;
990 	initctx->event_callback_cs = GSEL(GCODE_SEL, SEL_KPL);
991 	initctx->failsafe_callback_eip = (unsigned long)failsafe_callback;
992 	initctx->failsafe_callback_cs = GSEL(GCODE_SEL, SEL_KPL);
993 
994 	return;
995 }
996 #endif /* __x86_64__ */
997 
998 int
999 mp_cpu_start(struct cpu_info *ci, vaddr_t target)
1000 {
1001 	int hyperror;
1002 	struct vcpu_guest_context vcpuctx;
1003 
1004 	KASSERT(ci != NULL);
1005 	KASSERT(ci != &cpu_info_primary);
1006 	KASSERT(ci->ci_flags & CPUF_AP);
1007 
1008 #ifdef __x86_64__
1009 	xen_init_amd64_vcpuctxt(ci, &vcpuctx, (void (*)(struct cpu_info *))target);
1010 #else
1011 	xen_init_i386_vcpuctxt(ci, &vcpuctx, (void (*)(struct cpu_info *))target);
1012 #endif
1013 
1014 	/* Initialise the given vcpu to execute cpu_hatch(ci); */
1015 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_initialise, ci->ci_cpuid, &vcpuctx))) {
1016 		aprint_error(": context initialisation failed. errno = %d\n", hyperror);
1017 		return hyperror;
1018 	}
1019 
1020 	/* Start it up */
1021 
1022 	/* First bring it down */
1023 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_down, ci->ci_cpuid, NULL))) {
1024 		aprint_error(": VCPUOP_down hypervisor command failed. errno = %d\n", hyperror);
1025 		return hyperror;
1026 	}
1027 
1028 	if ((hyperror = HYPERVISOR_vcpu_op(VCPUOP_up, ci->ci_cpuid, NULL))) {
1029 		aprint_error(": VCPUOP_up hypervisor command failed. errno = %d\n", hyperror);
1030 		return hyperror;
1031 	}
1032 
1033 	if (!vcpu_is_up(ci)) {
1034 		aprint_error(": did not come up\n");
1035 		return -1;
1036 	}
1037 
1038 	return 0;
1039 }
1040 
1041 void
1042 mp_cpu_start_cleanup(struct cpu_info *ci)
1043 {
1044 	if (vcpu_is_up(ci)) {
1045 		aprint_debug_dev(ci->ci_dev, "is started.\n");
1046 	} else {
1047 		aprint_error_dev(ci->ci_dev, "did not start up.\n");
1048 	}
1049 }
1050 
1051 void
1052 cpu_init_msrs(struct cpu_info *ci, bool full)
1053 {
1054 #ifdef __x86_64__
1055 	if (full) {
1056 		HYPERVISOR_set_segment_base(SEGBASE_FS, 0);
1057 		HYPERVISOR_set_segment_base(SEGBASE_GS_KERNEL, (uint64_t)ci);
1058 		HYPERVISOR_set_segment_base(SEGBASE_GS_USER, 0);
1059 	}
1060 #endif
1061 
1062 	if (cpu_feature[2] & CPUID_NOX)
1063 		wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_NXE);
1064 }
1065 
1066 void
1067 cpu_offline_md(void)
1068 {
1069 	int s;
1070 
1071 	s = splhigh();
1072 	fpusave_cpu(true);
1073 	splx(s);
1074 }
1075 
1076 void
1077 cpu_get_tsc_freq(struct cpu_info *ci)
1078 {
1079 	uint32_t vcpu_tversion;
1080 	const volatile vcpu_time_info_t *tinfo = &ci->ci_vcpu->time;
1081 
1082 	vcpu_tversion = tinfo->version;
1083 	while (tinfo->version == vcpu_tversion); /* Wait for a time update. XXX: timeout ? */
1084 
1085 	uint64_t freq = 1000000000ULL << 32;
1086 	freq = freq / (uint64_t)tinfo->tsc_to_system_mul;
1087 	if (tinfo->tsc_shift < 0)
1088 		freq = freq << -tinfo->tsc_shift;
1089 	else
1090 		freq = freq >> tinfo->tsc_shift;
1091 	ci->ci_data.cpu_cc_freq = freq;
1092 }
1093 
1094 void
1095 x86_cpu_idle_xen(void)
1096 {
1097 	struct cpu_info *ci = curcpu();
1098 
1099 	KASSERT(ci->ci_ilevel == IPL_NONE);
1100 
1101 	x86_disable_intr();
1102 	if (!__predict_false(ci->ci_want_resched)) {
1103 		idle_block();
1104 	} else {
1105 		x86_enable_intr();
1106 	}
1107 }
1108 
1109 /*
1110  * Loads pmap for the current CPU.
1111  */
1112 void
1113 cpu_load_pmap(struct pmap *pmap, struct pmap *oldpmap)
1114 {
1115 	struct cpu_info *ci = curcpu();
1116 	cpuid_t cid = cpu_index(ci);
1117 	int i;
1118 
1119 	KASSERT(pmap != pmap_kernel());
1120 
1121 	mutex_enter(&ci->ci_kpm_mtx);
1122 	/* make new pmap visible to xen_kpm_sync() */
1123 	kcpuset_atomic_set(pmap->pm_xen_ptp_cpus, cid);
1124 
1125 #ifdef __x86_64__
1126 	pd_entry_t *new_pgd;
1127 	paddr_t l4_pd_ma;
1128 
1129 	l4_pd_ma = xpmap_ptom_masked(ci->ci_kpm_pdirpa);
1130 
1131 	/*
1132 	 * Map user space address in kernel space and load
1133 	 * user cr3
1134 	 */
1135 	new_pgd = pmap->pm_pdir;
1136 	KASSERT(pmap == ci->ci_pmap);
1137 
1138 	/* Copy user pmap L4 PDEs (in user addr. range) to per-cpu L4 */
1139 	for (i = 0; i < PDIR_SLOT_USERLIM; i++) {
1140 		KASSERT(pmap != pmap_kernel() || new_pgd[i] == 0);
1141 		if (ci->ci_kpm_pdir[i] != new_pgd[i]) {
1142 			xpq_queue_pte_update(l4_pd_ma + i * sizeof(pd_entry_t),
1143 			    new_pgd[i]);
1144 		}
1145 	}
1146 
1147 	xen_set_user_pgd(pmap_pdirpa(pmap, 0));
1148 	ci->ci_xen_current_user_pgd = pmap_pdirpa(pmap, 0);
1149 #else
1150 	paddr_t l3_pd = xpmap_ptom_masked(ci->ci_pae_l3_pdirpa);
1151 	/* don't update the kernel L3 slot */
1152 	for (i = 0; i < PDP_SIZE - 1; i++) {
1153 		xpq_queue_pte_update(l3_pd + i * sizeof(pd_entry_t),
1154 		    xpmap_ptom(pmap->pm_pdirpa[i]) | PTE_P);
1155 	}
1156 #endif
1157 
1158 	tlbflush();
1159 
1160 	/* old pmap no longer visible to xen_kpm_sync() */
1161 	if (oldpmap != pmap_kernel()) {
1162 		kcpuset_atomic_clear(oldpmap->pm_xen_ptp_cpus, cid);
1163 	}
1164 	mutex_exit(&ci->ci_kpm_mtx);
1165 }
1166 
1167 /*
1168  * pmap_cpu_init_late: perform late per-CPU initialization.
1169  *
1170  * Short note about percpu PDIR pages. Both the PAE and __x86_64__ architectures
1171  * have per-cpu PDIR tables, for two different reasons:
1172  *  - on PAE, this is to get around Xen's pagetable setup constraints (multiple
1173  *    L3[3]s cannot point to the same L2 - Xen will refuse to pin a table set up
1174  *    this way).
1175  *  - on __x86_64__, this is for multiple CPUs to map in different user pmaps
1176  *    (see cpu_load_pmap()).
1177  *
1178  * What this means for us is that the PDIR of the pmap_kernel() is considered
1179  * to be a canonical "SHADOW" PDIR with the following properties:
1180  *  - its recursive mapping points to itself
1181  *  - per-cpu recursive mappings point to themselves on __x86_64__
1182  *  - per-cpu L4 pages' kernel entries are expected to be in sync with
1183  *    the shadow
1184  */
1185 
1186 void
1187 pmap_cpu_init_late(struct cpu_info *ci)
1188 {
1189 	int i;
1190 
1191 	/*
1192 	 * The BP has already its own PD page allocated during early
1193 	 * MD startup.
1194 	 */
1195 
1196 #ifdef __x86_64__
1197 	/* Setup per-cpu normal_pdes */
1198 	extern pd_entry_t * const normal_pdes[];
1199 	for (i = 0;i < PTP_LEVELS - 1;i++) {
1200 		ci->ci_normal_pdes[i] = normal_pdes[i];
1201 	}
1202 #endif
1203 
1204 	if (ci == &cpu_info_primary)
1205 		return;
1206 
1207 	KASSERT(ci != NULL);
1208 
1209 #if defined(i386)
1210 	cpu_alloc_l3_page(ci);
1211 	KASSERT(ci->ci_pae_l3_pdirpa != 0);
1212 
1213 	/* Initialise L2 entries 0 - 2: Point them to pmap_kernel() */
1214 	for (i = 0; i < PDP_SIZE - 1; i++) {
1215 		ci->ci_pae_l3_pdir[i] =
1216 		    xpmap_ptom_masked(pmap_kernel()->pm_pdirpa[i]) | PTE_P;
1217 	}
1218 #endif
1219 
1220 	ci->ci_kpm_pdir = (pd_entry_t *)uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
1221 	    UVM_KMF_WIRED | UVM_KMF_ZERO | UVM_KMF_NOWAIT);
1222 
1223 	if (ci->ci_kpm_pdir == NULL) {
1224 		panic("%s: failed to allocate L4 per-cpu PD for CPU %d\n",
1225 		    __func__, cpu_index(ci));
1226 	}
1227 	ci->ci_kpm_pdirpa = vtophys((vaddr_t)ci->ci_kpm_pdir);
1228 	KASSERT(ci->ci_kpm_pdirpa != 0);
1229 
1230 #ifdef __x86_64__
1231 	extern pt_entry_t xpmap_pg_nx;
1232 
1233 	/* Copy over the pmap_kernel() shadow L4 entries */
1234 	memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir, PAGE_SIZE);
1235 
1236 	/* Recursive kernel mapping */
1237 	ci->ci_kpm_pdir[PDIR_SLOT_PTE] = xpmap_ptom_masked(ci->ci_kpm_pdirpa)
1238 	    | PTE_P | xpmap_pg_nx;
1239 #else
1240 	/* Copy over the pmap_kernel() shadow L2 entries */
1241 	memcpy(ci->ci_kpm_pdir, pmap_kernel()->pm_pdir + PDIR_SLOT_KERN,
1242 	    nkptp[PTP_LEVELS - 1] * sizeof(pd_entry_t));
1243 #endif
1244 
1245 	/* Xen wants a RO pdir. */
1246 	pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_kpm_pdir,
1247 	    (vaddr_t)ci->ci_kpm_pdir + PAGE_SIZE, VM_PROT_READ);
1248 	pmap_update(pmap_kernel());
1249 
1250 #ifdef __x86_64__
1251 	xpq_queue_pin_l4_table(xpmap_ptom_masked(ci->ci_kpm_pdirpa));
1252 #else
1253 	/*
1254 	 * Initialize L3 entry 3. This mapping is shared across all pmaps and is
1255 	 * static, ie: loading a new pmap will not update this entry.
1256 	 */
1257 	ci->ci_pae_l3_pdir[3] = xpmap_ptom_masked(ci->ci_kpm_pdirpa) | PTE_P;
1258 
1259 	/* Xen wants a RO L3. */
1260 	pmap_protect(pmap_kernel(), (vaddr_t)ci->ci_pae_l3_pdir,
1261 	    (vaddr_t)ci->ci_pae_l3_pdir + PAGE_SIZE, VM_PROT_READ);
1262 	pmap_update(pmap_kernel());
1263 
1264 	xpq_queue_pin_l3_table(xpmap_ptom_masked(ci->ci_pae_l3_pdirpa));
1265 #endif
1266 }
1267 
1268 /*
1269  * Notify all other cpus to halt.
1270  */
1271 
1272 void
1273 cpu_broadcast_halt(void)
1274 {
1275 	xen_broadcast_ipi(XEN_IPI_HALT);
1276 }
1277 
1278 /*
1279  * Send a dummy ipi to a cpu.
1280  */
1281 
1282 void
1283 cpu_kick(struct cpu_info *ci)
1284 {
1285 	(void)xen_send_ipi(ci, XEN_IPI_KICK);
1286 }
1287