mp_machdep.c revision 153241
1/*-
2 * Copyright (c) 1996, by Steve Passe
3 * Copyright (c) 2003, by Peter Wemm
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. The name of the developer may NOT be used to endorse or promote products
12 *    derived from this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/amd64/amd64/mp_machdep.c 153241 2005-12-08 18:33:30Z jhb $");
29
30#include "opt_cpu.h"
31#include "opt_kstack_pages.h"
32#include "opt_mp_watchdog.h"
33#include "opt_sched.h"
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/bus.h>
38#ifdef GPROF
39#include <sys/gmon.h>
40#endif
41#include <sys/kernel.h>
42#include <sys/ktr.h>
43#include <sys/lock.h>
44#include <sys/malloc.h>
45#include <sys/memrange.h>
46#include <sys/mutex.h>
47#include <sys/pcpu.h>
48#include <sys/proc.h>
49#include <sys/smp.h>
50#include <sys/sysctl.h>
51
52#include <vm/vm.h>
53#include <vm/vm_param.h>
54#include <vm/pmap.h>
55#include <vm/vm_kern.h>
56#include <vm/vm_extern.h>
57
58#include <machine/apicreg.h>
59#include <machine/clock.h>
60#include <machine/md_var.h>
61#include <machine/mp_watchdog.h>
62#include <machine/pcb.h>
63#include <machine/psl.h>
64#include <machine/smp.h>
65#include <machine/specialreg.h>
66#include <machine/tss.h>
67
68#define WARMBOOT_TARGET		0
69#define WARMBOOT_OFF		(KERNBASE + 0x0467)
70#define WARMBOOT_SEG		(KERNBASE + 0x0469)
71
72#define CMOS_REG		(0x70)
73#define CMOS_DATA		(0x71)
74#define BIOS_RESET		(0x0f)
75#define BIOS_WARM		(0x0a)
76
77/* lock region used by kernel profiling */
78int	mcount_lock;
79
80int	mp_naps;		/* # of Applications processors */
81int	boot_cpu_id = -1;	/* designated BSP */
82extern	int nkpt;
83
84/*
85 * CPU topology map datastructures for HTT.
86 */
87static struct cpu_group mp_groups[MAXCPU];
88static struct cpu_top mp_top;
89
90/* AP uses this during bootstrap.  Do not staticize.  */
91char *bootSTK;
92static int bootAP;
93
94/* Free these after use */
95void *bootstacks[MAXCPU];
96
97/* Temporary holder for double fault stack */
98char *doublefault_stack;
99
100/* Hotwire a 0->4MB V==P mapping */
101extern pt_entry_t *KPTphys;
102
103/* SMP page table page */
104extern pt_entry_t *SMPpt;
105
106struct pcb stoppcbs[MAXCPU];
107
108/* Variables needed for SMP tlb shootdown. */
109vm_offset_t smp_tlb_addr1;
110vm_offset_t smp_tlb_addr2;
111volatile int smp_tlb_wait;
112
113extern inthand_t IDTVEC(fast_syscall), IDTVEC(fast_syscall32);
114
115#ifdef STOP_NMI
116volatile cpumask_t ipi_nmi_pending;
117
118static void	ipi_nmi_selected(u_int32_t cpus);
119#endif
120
121/*
122 * Local data and functions.
123 */
124
125#ifdef STOP_NMI
126/*
127 * Provide an alternate method of stopping other CPUs. If another CPU has
128 * disabled interrupts the conventional STOP IPI will be blocked. This
129 * NMI-based stop should get through in that case.
130 */
131static int stop_cpus_with_nmi = 1;
132SYSCTL_INT(_debug, OID_AUTO, stop_cpus_with_nmi, CTLTYPE_INT | CTLFLAG_RW,
133    &stop_cpus_with_nmi, 0, "");
134TUNABLE_INT("debug.stop_cpus_with_nmi", &stop_cpus_with_nmi);
135#else
136#define	stop_cpus_with_nmi	0
137#endif
138
139static u_int logical_cpus;
140
141/* used to hold the AP's until we are ready to release them */
142static struct mtx ap_boot_mtx;
143
144/* Set to 1 once we're ready to let the APs out of the pen. */
145static volatile int aps_ready = 0;
146
147/*
148 * Store data from cpu_add() until later in the boot when we actually setup
149 * the APs.
150 */
151struct cpu_info {
152	int	cpu_present:1;
153	int	cpu_bsp:1;
154	int	cpu_disabled:1;
155} static cpu_info[MAXCPU];
156static int cpu_apic_ids[MAXCPU];
157
158/* Holds pending bitmap based IPIs per CPU */
159static volatile u_int cpu_ipi_pending[MAXCPU];
160
161static u_int boot_address;
162
163static void	set_logical_apic_ids(void);
164static int	start_all_aps(void);
165static int	start_ap(int apic_id);
166static void	release_aps(void *dummy);
167
168static int	hlt_logical_cpus;
169static u_int	hyperthreading_cpus;
170static cpumask_t	hyperthreading_cpus_mask;
171static int	hyperthreading_allowed = 1;
172static struct	sysctl_ctx_list logical_cpu_clist;
173static u_int	bootMP_size;
174
175static void
176mem_range_AP_init(void)
177{
178	if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
179		mem_range_softc.mr_op->initAP(&mem_range_softc);
180}
181
182void
183mp_topology(void)
184{
185	struct cpu_group *group;
186	int logical_cpus;
187	int apic_id;
188	int groups;
189	int cpu;
190
191	/* Build the smp_topology map. */
192	/* Nothing to do if there is no HTT support. */
193	if ((cpu_feature & CPUID_HTT) == 0)
194		return;
195	logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
196	if (logical_cpus <= 1)
197		return;
198	group = &mp_groups[0];
199	groups = 1;
200	for (cpu = 0, apic_id = 0; apic_id < MAXCPU; apic_id++) {
201		if (!cpu_info[apic_id].cpu_present)
202			continue;
203		/*
204		 * If the current group has members and we're not a logical
205		 * cpu, create a new group.
206		 */
207		if (group->cg_count != 0 && (apic_id % logical_cpus) == 0) {
208			group++;
209			groups++;
210		}
211		group->cg_count++;
212		group->cg_mask |= 1 << cpu;
213		cpu++;
214	}
215
216	mp_top.ct_count = groups;
217	mp_top.ct_group = mp_groups;
218	smp_topology = &mp_top;
219}
220
221/*
222 * Calculate usable address in base memory for AP trampoline code.
223 */
224u_int
225mp_bootaddress(u_int basemem)
226{
227
228	bootMP_size = mptramp_end - mptramp_start;
229	boot_address = trunc_page(basemem * 1024); /* round down to 4k boundary */
230	if (((basemem * 1024) - boot_address) < bootMP_size)
231		boot_address -= PAGE_SIZE;	/* not enough, lower by 4k */
232	/* 3 levels of page table pages */
233	mptramp_pagetables = boot_address - (PAGE_SIZE * 3);
234
235	return mptramp_pagetables;
236}
237
238void
239cpu_add(u_int apic_id, char boot_cpu)
240{
241
242	if (apic_id >= MAXCPU) {
243		printf("SMP: CPU %d exceeds maximum CPU %d, ignoring\n",
244		    apic_id, MAXCPU - 1);
245		return;
246	}
247	KASSERT(cpu_info[apic_id].cpu_present == 0, ("CPU %d added twice",
248	    apic_id));
249	cpu_info[apic_id].cpu_present = 1;
250	if (boot_cpu) {
251		KASSERT(boot_cpu_id == -1,
252		    ("CPU %d claims to be BSP, but CPU %d already is", apic_id,
253		    boot_cpu_id));
254		boot_cpu_id = apic_id;
255		cpu_info[apic_id].cpu_bsp = 1;
256	}
257	mp_ncpus++;
258	if (apic_id > mp_maxid)
259		mp_maxid = apic_id;
260	if (bootverbose)
261		printf("SMP: Added CPU %d (%s)\n", apic_id, boot_cpu ? "BSP" :
262		    "AP");
263
264}
265
266void
267cpu_mp_setmaxid(void)
268{
269
270	/*
271	 * mp_maxid should be already set by calls to cpu_add().
272	 * Just sanity check its value here.
273	 */
274	if (mp_ncpus == 0)
275		KASSERT(mp_maxid == 0,
276		    ("%s: mp_ncpus is zero, but mp_maxid is not", __func__));
277	else if (mp_ncpus == 1)
278		mp_maxid = 0;
279	else
280		KASSERT(mp_maxid >= mp_ncpus - 1,
281		    ("%s: counters out of sync: max %d, count %d", __func__,
282			mp_maxid, mp_ncpus));
283
284}
285
286int
287cpu_mp_probe(void)
288{
289
290	/*
291	 * Always record BSP in CPU map so that the mbuf init code works
292	 * correctly.
293	 */
294	all_cpus = 1;
295	if (mp_ncpus == 0) {
296		/*
297		 * No CPUs were found, so this must be a UP system.  Setup
298		 * the variables to represent a system with a single CPU
299		 * with an id of 0.
300		 */
301		mp_ncpus = 1;
302		return (0);
303	}
304
305	/* At least one CPU was found. */
306	if (mp_ncpus == 1) {
307		/*
308		 * One CPU was found, so this must be a UP system with
309		 * an I/O APIC.
310		 */
311		mp_maxid = 0;
312		return (0);
313	}
314
315	/* At least two CPUs were found. */
316	return (1);
317}
318
319/*
320 * Initialize the IPI handlers and start up the AP's.
321 */
322void
323cpu_mp_start(void)
324{
325	int i;
326	u_int threads_per_cache, p[4];
327
328	/* Initialize the logical ID to APIC ID table. */
329	for (i = 0; i < MAXCPU; i++) {
330		cpu_apic_ids[i] = -1;
331		cpu_ipi_pending[i] = 0;
332	}
333
334	/* Install an inter-CPU IPI for TLB invalidation */
335	setidt(IPI_INVLTLB, IDTVEC(invltlb), SDT_SYSIGT, SEL_KPL, 0);
336	setidt(IPI_INVLPG, IDTVEC(invlpg), SDT_SYSIGT, SEL_KPL, 0);
337	setidt(IPI_INVLRNG, IDTVEC(invlrng), SDT_SYSIGT, SEL_KPL, 0);
338
339	/* Install an inter-CPU IPI for all-CPU rendezvous */
340	setidt(IPI_RENDEZVOUS, IDTVEC(rendezvous), SDT_SYSIGT, SEL_KPL, 0);
341
342	/* Install generic inter-CPU IPI handler */
343	setidt(IPI_BITMAP_VECTOR, IDTVEC(ipi_intr_bitmap_handler),
344	       SDT_SYSIGT, SEL_KPL, 0);
345
346	/* Install an inter-CPU IPI for CPU stop/restart */
347	setidt(IPI_STOP, IDTVEC(cpustop), SDT_SYSIGT, SEL_KPL, 0);
348
349	/* Set boot_cpu_id if needed. */
350	if (boot_cpu_id == -1) {
351		boot_cpu_id = PCPU_GET(apic_id);
352		cpu_info[boot_cpu_id].cpu_bsp = 1;
353	} else
354		KASSERT(boot_cpu_id == PCPU_GET(apic_id),
355		    ("BSP's APIC ID doesn't match boot_cpu_id"));
356	cpu_apic_ids[0] = boot_cpu_id;
357
358	/* Start each Application Processor */
359	start_all_aps();
360
361	/* Setup the initial logical CPUs info. */
362	logical_cpus = logical_cpus_mask = 0;
363	if (cpu_feature & CPUID_HTT)
364		logical_cpus = (cpu_procinfo & CPUID_HTT_CORES) >> 16;
365
366	/*
367	 * Work out if hyperthreading is *really* enabled.  This
368	 * is made really ugly by the fact that processors lie: Dual
369	 * core processors claim to be hyperthreaded even when they're
370	 * not, presumably because they want to be treated the same
371	 * way as HTT with respect to per-cpu software licensing.
372	 * At the time of writing (May 12, 2005) the only hyperthreaded
373	 * cpus are from Intel, and Intel's dual-core processors can be
374	 * identified via the "deterministic cache parameters" cpuid
375	 * calls.
376	 */
377	/*
378	 * First determine if this is an Intel processor which claims
379	 * to have hyperthreading support.
380	 */
381	if ((cpu_feature & CPUID_HTT) &&
382	    (strcmp(cpu_vendor, "GenuineIntel") == 0)) {
383		/*
384		 * If the "deterministic cache parameters" cpuid calls
385		 * are available, use them.
386		 */
387		if (cpu_high >= 4) {
388			/* Ask the processor about up to 32 caches. */
389			for (i = 0; i < 32; i++) {
390				cpuid_count(4, i, p);
391				threads_per_cache = ((p[0] & 0x3ffc000) >> 14) + 1;
392				if (hyperthreading_cpus < threads_per_cache)
393					hyperthreading_cpus = threads_per_cache;
394				if ((p[0] & 0x1f) == 0)
395					break;
396			}
397		}
398
399		/*
400		 * If the deterministic cache parameters are not
401		 * available, or if no caches were reported to exist,
402		 * just accept what the HTT flag indicated.
403		 */
404		if (hyperthreading_cpus == 0)
405			hyperthreading_cpus = logical_cpus;
406	}
407
408	set_logical_apic_ids();
409}
410
411
412/*
413 * Print various information about the SMP system hardware and setup.
414 */
415void
416cpu_mp_announce(void)
417{
418	int i, x;
419
420	/* List CPUs */
421	printf(" cpu0 (BSP): APIC ID: %2d\n", boot_cpu_id);
422	for (i = 1, x = 0; x < MAXCPU; x++) {
423		if (!cpu_info[x].cpu_present || cpu_info[x].cpu_bsp)
424			continue;
425		if (cpu_info[x].cpu_disabled)
426			printf("  cpu (AP): APIC ID: %2d (disabled)\n", x);
427		else {
428			KASSERT(i < mp_ncpus,
429			    ("mp_ncpus and actual cpus are out of whack"));
430			printf(" cpu%d (AP): APIC ID: %2d\n", i++, x);
431		}
432	}
433}
434
435/*
436 * AP CPU's call this to initialize themselves.
437 */
438void
439init_secondary(void)
440{
441	struct pcpu *pc;
442	u_int64_t msr, cr0;
443	int cpu, gsel_tss;
444
445	/* Set by the startup code for us to use */
446	cpu = bootAP;
447
448	/* Init tss */
449	common_tss[cpu] = common_tss[0];
450	common_tss[cpu].tss_rsp0 = 0;   /* not used until after switch */
451	common_tss[cpu].tss_iobase = sizeof(struct amd64tss);
452	common_tss[cpu].tss_ist1 = (long)&doublefault_stack[PAGE_SIZE];
453
454	gdt_segs[GPROC0_SEL].ssd_base = (long) &common_tss[cpu];
455	ssdtosyssd(&gdt_segs[GPROC0_SEL],
456	   (struct system_segment_descriptor *)&gdt[GPROC0_SEL]);
457
458	lgdt(&r_gdt);			/* does magic intra-segment return */
459
460	/* Get per-cpu data */
461	pc = &__pcpu[cpu];
462
463	/* prime data page for it to use */
464	pcpu_init(pc, cpu, sizeof(struct pcpu));
465	pc->pc_apic_id = cpu_apic_ids[cpu];
466	pc->pc_prvspace = pc;
467	pc->pc_curthread = 0;
468	pc->pc_tssp = &common_tss[cpu];
469	pc->pc_rsp0 = 0;
470
471	wrmsr(MSR_FSBASE, 0);		/* User value */
472	wrmsr(MSR_GSBASE, (u_int64_t)pc);
473	wrmsr(MSR_KGSBASE, (u_int64_t)pc);	/* XXX User value while we're in the kernel */
474
475	lidt(&r_idt);
476
477	gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
478	ltr(gsel_tss);
479
480	/*
481	 * Set to a known state:
482	 * Set by mpboot.s: CR0_PG, CR0_PE
483	 * Set by cpu_setregs: CR0_NE, CR0_MP, CR0_TS, CR0_WP, CR0_AM
484	 */
485	cr0 = rcr0();
486	cr0 &= ~(CR0_CD | CR0_NW | CR0_EM);
487	load_cr0(cr0);
488
489	/* Set up the fast syscall stuff */
490	msr = rdmsr(MSR_EFER) | EFER_SCE;
491	wrmsr(MSR_EFER, msr);
492	wrmsr(MSR_LSTAR, (u_int64_t)IDTVEC(fast_syscall));
493	wrmsr(MSR_CSTAR, (u_int64_t)IDTVEC(fast_syscall32));
494	msr = ((u_int64_t)GSEL(GCODE_SEL, SEL_KPL) << 32) |
495	      ((u_int64_t)GSEL(GUCODE32_SEL, SEL_UPL) << 48);
496	wrmsr(MSR_STAR, msr);
497	wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D);
498
499	/* Disable local APIC just to be sure. */
500	lapic_disable();
501
502	/* signal our startup to the BSP. */
503	mp_naps++;
504
505	/* Spin until the BSP releases the AP's. */
506	while (!aps_ready)
507		ia32_pause();
508
509	/* set up CPU registers and state */
510	cpu_setregs();
511
512	/* set up SSE/NX registers */
513	initializecpu();
514
515	/* set up FPU state on the AP */
516	fpuinit();
517
518	/* A quick check from sanity claus */
519	if (PCPU_GET(apic_id) != lapic_id()) {
520		printf("SMP: cpuid = %d\n", PCPU_GET(cpuid));
521		printf("SMP: actual apic_id = %d\n", lapic_id());
522		printf("SMP: correct apic_id = %d\n", PCPU_GET(apic_id));
523		panic("cpuid mismatch! boom!!");
524	}
525
526	/* Initialize curthread. */
527	KASSERT(PCPU_GET(idlethread) != NULL, ("no idle thread"));
528	PCPU_SET(curthread, PCPU_GET(idlethread));
529
530	mtx_lock_spin(&ap_boot_mtx);
531
532	/* Init local apic for irq's */
533	lapic_setup();
534
535	/* Set memory range attributes for this CPU to match the BSP */
536	mem_range_AP_init();
537
538	smp_cpus++;
539
540	CTR1(KTR_SMP, "SMP: AP CPU #%d Launched", PCPU_GET(cpuid));
541	printf("SMP: AP CPU #%d Launched!\n", PCPU_GET(cpuid));
542
543	/* Determine if we are a logical CPU. */
544	if (logical_cpus > 1 && PCPU_GET(apic_id) % logical_cpus != 0)
545		logical_cpus_mask |= PCPU_GET(cpumask);
546
547	/* Determine if we are a hyperthread. */
548	if (hyperthreading_cpus > 1 &&
549	    PCPU_GET(apic_id) % hyperthreading_cpus != 0)
550		hyperthreading_cpus_mask |= PCPU_GET(cpumask);
551
552	/* Build our map of 'other' CPUs. */
553	PCPU_SET(other_cpus, all_cpus & ~PCPU_GET(cpumask));
554
555	if (bootverbose)
556		lapic_dump("AP");
557
558	if (smp_cpus == mp_ncpus) {
559		/* enable IPI's, tlb shootdown, freezes etc */
560		atomic_store_rel_int(&smp_started, 1);
561		smp_active = 1;	 /* historic */
562	}
563
564	mtx_unlock_spin(&ap_boot_mtx);
565
566	/* wait until all the AP's are up */
567	while (smp_started == 0)
568		ia32_pause();
569
570	/* ok, now grab sched_lock and enter the scheduler */
571	mtx_lock_spin(&sched_lock);
572
573	/*
574	 * Correct spinlock nesting.  The idle thread context that we are
575	 * borrowing was created so that it would start out with a single
576	 * spin lock (sched_lock) held in fork_trampoline().  Since we've
577	 * explicitly acquired locks in this function, the nesting count
578	 * is now 2 rather than 1.  Since we are nested, calling
579	 * spinlock_exit() will simply adjust the counts without allowing
580	 * spin lock using code to interrupt us.
581	 */
582	spinlock_exit();
583	KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count"));
584
585	binuptime(PCPU_PTR(switchtime));
586	PCPU_SET(switchticks, ticks);
587
588	cpu_throw(NULL, choosethread());	/* doesn't return */
589
590	panic("scheduler returned us to %s", __func__);
591	/* NOTREACHED */
592}
593
594/*******************************************************************
595 * local functions and data
596 */
597
598/*
599 * Set the APIC logical IDs.
600 *
601 * We want to cluster logical CPU's within the same APIC ID cluster.
602 * Since logical CPU's are aligned simply filling in the clusters in
603 * APIC ID order works fine.  Note that this does not try to balance
604 * the number of CPU's in each cluster. (XXX?)
605 */
606static void
607set_logical_apic_ids(void)
608{
609	u_int apic_id, cluster, cluster_id;
610
611	/* Force us to allocate cluster 0 at the start. */
612	cluster = -1;
613	cluster_id = APIC_MAX_INTRACLUSTER_ID;
614	for (apic_id = 0; apic_id < MAXCPU; apic_id++) {
615		if (!cpu_info[apic_id].cpu_present)
616			continue;
617		if (cluster_id == APIC_MAX_INTRACLUSTER_ID) {
618			cluster = ioapic_next_logical_cluster();
619			cluster_id = 0;
620		} else
621			cluster_id++;
622		if (bootverbose)
623			printf("APIC ID: physical %u, logical %u:%u\n",
624			    apic_id, cluster, cluster_id);
625		lapic_set_logical_id(apic_id, cluster, cluster_id);
626	}
627}
628
629/*
630 * start each AP in our list
631 */
632static int
633start_all_aps(void)
634{
635	vm_offset_t va = boot_address + KERNBASE;
636	u_int64_t *pt4, *pt3, *pt2;
637	u_int32_t mpbioswarmvec;
638	int apic_id, cpu, i;
639	u_char mpbiosreason;
640
641	mtx_init(&ap_boot_mtx, "ap boot", NULL, MTX_SPIN);
642
643	/* install the AP 1st level boot code */
644	pmap_kenter(va, boot_address);
645	pmap_invalidate_page(kernel_pmap, va);
646	bcopy(mptramp_start, (void *)va, bootMP_size);
647
648	/* Locate the page tables, they'll be below the trampoline */
649	pt4 = (u_int64_t *)(uintptr_t)(mptramp_pagetables + KERNBASE);
650	pt3 = pt4 + (PAGE_SIZE) / sizeof(u_int64_t);
651	pt2 = pt3 + (PAGE_SIZE) / sizeof(u_int64_t);
652
653	/* Create the initial 1GB replicated page tables */
654	for (i = 0; i < 512; i++) {
655		/* Each slot of the level 4 pages points to the same level 3 page */
656		pt4[i] = (u_int64_t)(uintptr_t)(mptramp_pagetables + PAGE_SIZE);
657		pt4[i] |= PG_V | PG_RW | PG_U;
658
659		/* Each slot of the level 3 pages points to the same level 2 page */
660		pt3[i] = (u_int64_t)(uintptr_t)(mptramp_pagetables + (2 * PAGE_SIZE));
661		pt3[i] |= PG_V | PG_RW | PG_U;
662
663		/* The level 2 page slots are mapped with 2MB pages for 1GB. */
664		pt2[i] = i * (2 * 1024 * 1024);
665		pt2[i] |= PG_V | PG_RW | PG_PS | PG_U;
666	}
667
668	/* save the current value of the warm-start vector */
669	mpbioswarmvec = *((u_int32_t *) WARMBOOT_OFF);
670	outb(CMOS_REG, BIOS_RESET);
671	mpbiosreason = inb(CMOS_DATA);
672
673	/* setup a vector to our boot code */
674	*((volatile u_short *) WARMBOOT_OFF) = WARMBOOT_TARGET;
675	*((volatile u_short *) WARMBOOT_SEG) = (boot_address >> 4);
676	outb(CMOS_REG, BIOS_RESET);
677	outb(CMOS_DATA, BIOS_WARM);	/* 'warm-start' */
678
679	/* start each AP */
680	for (cpu = 0, apic_id = 0; apic_id < MAXCPU; apic_id++) {
681
682		/* Ignore non-existent CPUs and the BSP. */
683		if (!cpu_info[apic_id].cpu_present ||
684		    cpu_info[apic_id].cpu_bsp)
685			continue;
686
687		/* Don't use this CPU if it has been disabled by a tunable. */
688		if (resource_disabled("lapic", apic_id)) {
689			cpu_info[apic_id].cpu_disabled = 1;
690			mp_ncpus--;
691			continue;
692		}
693
694		cpu++;
695
696		/* save APIC ID for this logical ID */
697		cpu_apic_ids[cpu] = apic_id;
698
699		/* allocate and set up an idle stack data page */
700		bootstacks[cpu] = (void *)kmem_alloc(kernel_map, KSTACK_PAGES * PAGE_SIZE);
701		doublefault_stack = (char *)kmem_alloc(kernel_map, PAGE_SIZE);
702
703		bootSTK = (char *)bootstacks[cpu] + KSTACK_PAGES * PAGE_SIZE - 8;
704		bootAP = cpu;
705
706		/* attempt to start the Application Processor */
707		if (!start_ap(apic_id)) {
708			/* restore the warmstart vector */
709			*(u_int32_t *) WARMBOOT_OFF = mpbioswarmvec;
710			panic("AP #%d (PHY# %d) failed!", cpu, apic_id);
711		}
712
713		all_cpus |= (1 << cpu);		/* record AP in CPU map */
714	}
715
716	/* build our map of 'other' CPUs */
717	PCPU_SET(other_cpus, all_cpus & ~PCPU_GET(cpumask));
718
719	/* restore the warmstart vector */
720	*(u_int32_t *) WARMBOOT_OFF = mpbioswarmvec;
721
722	outb(CMOS_REG, BIOS_RESET);
723	outb(CMOS_DATA, mpbiosreason);
724
725	/* number of APs actually started */
726	return mp_naps;
727}
728
729
730/*
731 * This function starts the AP (application processor) identified
732 * by the APIC ID 'physicalCpu'.  It does quite a "song and dance"
733 * to accomplish this.  This is necessary because of the nuances
734 * of the different hardware we might encounter.  It isn't pretty,
735 * but it seems to work.
736 */
737static int
738start_ap(int apic_id)
739{
740	int vector, ms;
741	int cpus;
742
743	/* calculate the vector */
744	vector = (boot_address >> 12) & 0xff;
745
746	/* used as a watchpoint to signal AP startup */
747	cpus = mp_naps;
748
749	/*
750	 * first we do an INIT/RESET IPI this INIT IPI might be run, reseting
751	 * and running the target CPU. OR this INIT IPI might be latched (P5
752	 * bug), CPU waiting for STARTUP IPI. OR this INIT IPI might be
753	 * ignored.
754	 */
755
756	/* do an INIT IPI: assert RESET */
757	lapic_ipi_raw(APIC_DEST_DESTFLD | APIC_TRIGMOD_EDGE |
758	    APIC_LEVEL_ASSERT | APIC_DESTMODE_PHY | APIC_DELMODE_INIT, apic_id);
759
760	/* wait for pending status end */
761	lapic_ipi_wait(-1);
762
763	/* do an INIT IPI: deassert RESET */
764	lapic_ipi_raw(APIC_DEST_ALLESELF | APIC_TRIGMOD_LEVEL |
765	    APIC_LEVEL_DEASSERT | APIC_DESTMODE_PHY | APIC_DELMODE_INIT, 0);
766
767	/* wait for pending status end */
768	DELAY(10000);		/* wait ~10mS */
769	lapic_ipi_wait(-1);
770
771	/*
772	 * next we do a STARTUP IPI: the previous INIT IPI might still be
773	 * latched, (P5 bug) this 1st STARTUP would then terminate
774	 * immediately, and the previously started INIT IPI would continue. OR
775	 * the previous INIT IPI has already run. and this STARTUP IPI will
776	 * run. OR the previous INIT IPI was ignored. and this STARTUP IPI
777	 * will run.
778	 */
779
780	/* do a STARTUP IPI */
781	lapic_ipi_raw(APIC_DEST_DESTFLD | APIC_TRIGMOD_EDGE |
782	    APIC_LEVEL_DEASSERT | APIC_DESTMODE_PHY | APIC_DELMODE_STARTUP |
783	    vector, apic_id);
784	lapic_ipi_wait(-1);
785	DELAY(200);		/* wait ~200uS */
786
787	/*
788	 * finally we do a 2nd STARTUP IPI: this 2nd STARTUP IPI should run IF
789	 * the previous STARTUP IPI was cancelled by a latched INIT IPI. OR
790	 * this STARTUP IPI will be ignored, as only ONE STARTUP IPI is
791	 * recognized after hardware RESET or INIT IPI.
792	 */
793
794	lapic_ipi_raw(APIC_DEST_DESTFLD | APIC_TRIGMOD_EDGE |
795	    APIC_LEVEL_DEASSERT | APIC_DESTMODE_PHY | APIC_DELMODE_STARTUP |
796	    vector, apic_id);
797	lapic_ipi_wait(-1);
798	DELAY(200);		/* wait ~200uS */
799
800	/* Wait up to 5 seconds for it to start. */
801	for (ms = 0; ms < 5000; ms++) {
802		if (mp_naps > cpus)
803			return 1;	/* return SUCCESS */
804		DELAY(1000);
805	}
806	return 0;		/* return FAILURE */
807}
808
809/*
810 * Flush the TLB on all other CPU's
811 */
812static void
813smp_tlb_shootdown(u_int vector, vm_offset_t addr1, vm_offset_t addr2)
814{
815	u_int ncpu;
816
817	ncpu = mp_ncpus - 1;	/* does not shootdown self */
818	if (ncpu < 1)
819		return;		/* no other cpus */
820	mtx_assert(&smp_ipi_mtx, MA_OWNED);
821	smp_tlb_addr1 = addr1;
822	smp_tlb_addr2 = addr2;
823	atomic_store_rel_int(&smp_tlb_wait, 0);
824	ipi_all_but_self(vector);
825	while (smp_tlb_wait < ncpu)
826		ia32_pause();
827}
828
829static void
830smp_targeted_tlb_shootdown(u_int mask, u_int vector, vm_offset_t addr1, vm_offset_t addr2)
831{
832	int ncpu, othercpus;
833
834	othercpus = mp_ncpus - 1;
835	if (mask == (u_int)-1) {
836		ncpu = othercpus;
837		if (ncpu < 1)
838			return;
839	} else {
840		mask &= ~PCPU_GET(cpumask);
841		if (mask == 0)
842			return;
843		ncpu = bitcount32(mask);
844		if (ncpu > othercpus) {
845			/* XXX this should be a panic offence */
846			printf("SMP: tlb shootdown to %d other cpus (only have %d)\n",
847			    ncpu, othercpus);
848			ncpu = othercpus;
849		}
850		/* XXX should be a panic, implied by mask == 0 above */
851		if (ncpu < 1)
852			return;
853	}
854	mtx_assert(&smp_ipi_mtx, MA_OWNED);
855	smp_tlb_addr1 = addr1;
856	smp_tlb_addr2 = addr2;
857	atomic_store_rel_int(&smp_tlb_wait, 0);
858	if (mask == (u_int)-1)
859		ipi_all_but_self(vector);
860	else
861		ipi_selected(mask, vector);
862	while (smp_tlb_wait < ncpu)
863		ia32_pause();
864}
865
866void
867smp_invltlb(void)
868{
869
870	if (smp_started) {
871		smp_tlb_shootdown(IPI_INVLTLB, 0, 0);
872	}
873}
874
875void
876smp_invlpg(vm_offset_t addr)
877{
878
879	if (smp_started)
880		smp_tlb_shootdown(IPI_INVLPG, addr, 0);
881}
882
883void
884smp_invlpg_range(vm_offset_t addr1, vm_offset_t addr2)
885{
886
887	if (smp_started) {
888		smp_tlb_shootdown(IPI_INVLRNG, addr1, addr2);
889	}
890}
891
892void
893smp_masked_invltlb(u_int mask)
894{
895
896	if (smp_started) {
897		smp_targeted_tlb_shootdown(mask, IPI_INVLTLB, 0, 0);
898	}
899}
900
901void
902smp_masked_invlpg(u_int mask, vm_offset_t addr)
903{
904
905	if (smp_started) {
906		smp_targeted_tlb_shootdown(mask, IPI_INVLPG, addr, 0);
907	}
908}
909
910void
911smp_masked_invlpg_range(u_int mask, vm_offset_t addr1, vm_offset_t addr2)
912{
913
914	if (smp_started) {
915		smp_targeted_tlb_shootdown(mask, IPI_INVLRNG, addr1, addr2);
916	}
917}
918
919void
920ipi_bitmap_handler(struct clockframe frame)
921{
922	int cpu = PCPU_GET(cpuid);
923	u_int ipi_bitmap;
924
925	ipi_bitmap = atomic_readandclear_int(&cpu_ipi_pending[cpu]);
926
927#ifdef IPI_PREEMPTION
928	if (ipi_bitmap & IPI_PREEMPT) {
929		mtx_lock_spin(&sched_lock);
930		/* Don't preempt the idle thread */
931		if (curthread->td_priority <  PRI_MIN_IDLE) {
932			struct thread *running_thread = curthread;
933			if (running_thread->td_critnest > 1)
934				running_thread->td_owepreempt = 1;
935			else
936				mi_switch(SW_INVOL | SW_PREEMPT, NULL);
937		}
938		mtx_unlock_spin(&sched_lock);
939	}
940#endif
941
942	/* Nothing to do for AST */
943}
944
945/*
946 * send an IPI to a set of cpus.
947 */
948void
949ipi_selected(u_int32_t cpus, u_int ipi)
950{
951	int cpu;
952	u_int bitmap = 0;
953	u_int old_pending;
954	u_int new_pending;
955
956	if (IPI_IS_BITMAPED(ipi)) {
957		bitmap = 1 << ipi;
958		ipi = IPI_BITMAP_VECTOR;
959	}
960
961#ifdef STOP_NMI
962	if (ipi == IPI_STOP && stop_cpus_with_nmi) {
963		ipi_nmi_selected(cpus);
964		return;
965	}
966#endif
967	CTR3(KTR_SMP, "%s: cpus: %x ipi: %x", __func__, cpus, ipi);
968	while ((cpu = ffs(cpus)) != 0) {
969		cpu--;
970		cpus &= ~(1 << cpu);
971
972		KASSERT(cpu_apic_ids[cpu] != -1,
973		    ("IPI to non-existent CPU %d", cpu));
974
975		if (bitmap) {
976			do {
977				old_pending = cpu_ipi_pending[cpu];
978				new_pending = old_pending | bitmap;
979			} while  (!atomic_cmpset_int(&cpu_ipi_pending[cpu],old_pending, new_pending));
980
981			if (old_pending)
982				continue;
983		}
984
985		lapic_ipi_vectored(ipi, cpu_apic_ids[cpu]);
986	}
987
988}
989
990/*
991 * send an IPI INTerrupt containing 'vector' to all CPUs, including myself
992 */
993void
994ipi_all(u_int ipi)
995{
996
997	if (IPI_IS_BITMAPED(ipi) || (ipi == IPI_STOP && stop_cpus_with_nmi)) {
998		ipi_selected(all_cpus, ipi);
999		return;
1000	}
1001	CTR2(KTR_SMP, "%s: ipi: %x", __func__, ipi);
1002	lapic_ipi_vectored(ipi, APIC_IPI_DEST_ALL);
1003}
1004
1005/*
1006 * send an IPI to all CPUs EXCEPT myself
1007 */
1008void
1009ipi_all_but_self(u_int ipi)
1010{
1011
1012	if (IPI_IS_BITMAPED(ipi) || (ipi == IPI_STOP && stop_cpus_with_nmi)) {
1013		ipi_selected(PCPU_GET(other_cpus), ipi);
1014		return;
1015	}
1016	CTR2(KTR_SMP, "%s: ipi: %x", __func__, ipi);
1017	lapic_ipi_vectored(ipi, APIC_IPI_DEST_OTHERS);
1018}
1019
1020/*
1021 * send an IPI to myself
1022 */
1023void
1024ipi_self(u_int ipi)
1025{
1026
1027	if (IPI_IS_BITMAPED(ipi) || (ipi == IPI_STOP && stop_cpus_with_nmi)) {
1028		ipi_selected(PCPU_GET(cpumask), ipi);
1029		return;
1030	}
1031	CTR2(KTR_SMP, "%s: ipi: %x", __func__, ipi);
1032	lapic_ipi_vectored(ipi, APIC_IPI_DEST_SELF);
1033}
1034
1035#ifdef STOP_NMI
1036/*
1037 * send NMI IPI to selected CPUs
1038 */
1039
1040#define	BEFORE_SPIN	1000000
1041
1042void
1043ipi_nmi_selected(u_int32_t cpus)
1044{
1045	int cpu;
1046	register_t icrlo;
1047
1048	icrlo = APIC_DELMODE_NMI | APIC_DESTMODE_PHY | APIC_LEVEL_ASSERT
1049		| APIC_TRIGMOD_EDGE;
1050
1051	CTR2(KTR_SMP, "%s: cpus: %x nmi", __func__, cpus);
1052
1053	atomic_set_int(&ipi_nmi_pending, cpus);
1054
1055	while ((cpu = ffs(cpus)) != 0) {
1056		cpu--;
1057		cpus &= ~(1 << cpu);
1058
1059		KASSERT(cpu_apic_ids[cpu] != -1,
1060		    ("IPI NMI to non-existent CPU %d", cpu));
1061
1062		/* Wait for an earlier IPI to finish. */
1063		if (!lapic_ipi_wait(BEFORE_SPIN))
1064			panic("ipi_nmi_selected: previous IPI has not cleared");
1065
1066		lapic_ipi_raw(icrlo, cpu_apic_ids[cpu]);
1067	}
1068}
1069
1070int
1071ipi_nmi_handler(void)
1072{
1073	int cpumask = PCPU_GET(cpumask);
1074
1075	if (!(ipi_nmi_pending & cpumask))
1076		return 1;
1077
1078	atomic_clear_int(&ipi_nmi_pending, cpumask);
1079	cpustop_handler();
1080	return 0;
1081}
1082
1083#endif /* STOP_NMI */
1084
1085/*
1086 * Handle an IPI_STOP by saving our current context and spinning until we
1087 * are resumed.
1088 */
1089void
1090cpustop_handler(void)
1091{
1092	int cpu = PCPU_GET(cpuid);
1093	int cpumask = PCPU_GET(cpumask);
1094
1095	savectx(&stoppcbs[cpu]);
1096
1097	/* Indicate that we are stopped */
1098	atomic_set_int(&stopped_cpus, cpumask);
1099
1100	/* Wait for restart */
1101	while (!(started_cpus & cpumask))
1102	    ia32_pause();
1103
1104	atomic_clear_int(&started_cpus, cpumask);
1105	atomic_clear_int(&stopped_cpus, cpumask);
1106
1107	if (cpu == 0 && cpustop_restartfunc != NULL) {
1108		cpustop_restartfunc();
1109		cpustop_restartfunc = NULL;
1110	}
1111}
1112
1113/*
1114 * This is called once the rest of the system is up and running and we're
1115 * ready to let the AP's out of the pen.
1116 */
1117static void
1118release_aps(void *dummy __unused)
1119{
1120
1121	if (mp_ncpus == 1)
1122		return;
1123	mtx_lock_spin(&sched_lock);
1124	atomic_store_rel_int(&aps_ready, 1);
1125	while (smp_started == 0)
1126		ia32_pause();
1127	mtx_unlock_spin(&sched_lock);
1128}
1129SYSINIT(start_aps, SI_SUB_SMP, SI_ORDER_FIRST, release_aps, NULL);
1130
1131static int
1132sysctl_hlt_cpus(SYSCTL_HANDLER_ARGS)
1133{
1134	u_int mask;
1135	int error;
1136
1137	mask = hlt_cpus_mask;
1138	error = sysctl_handle_int(oidp, &mask, 0, req);
1139	if (error || !req->newptr)
1140		return (error);
1141
1142	if (logical_cpus_mask != 0 &&
1143	    (mask & logical_cpus_mask) == logical_cpus_mask)
1144		hlt_logical_cpus = 1;
1145	else
1146		hlt_logical_cpus = 0;
1147
1148	if (! hyperthreading_allowed)
1149		mask |= hyperthreading_cpus_mask;
1150
1151	if ((mask & all_cpus) == all_cpus)
1152		mask &= ~(1<<0);
1153	hlt_cpus_mask = mask;
1154	return (error);
1155}
1156SYSCTL_PROC(_machdep, OID_AUTO, hlt_cpus, CTLTYPE_INT|CTLFLAG_RW,
1157    0, 0, sysctl_hlt_cpus, "IU",
1158    "Bitmap of CPUs to halt.  101 (binary) will halt CPUs 0 and 2.");
1159
1160static int
1161sysctl_hlt_logical_cpus(SYSCTL_HANDLER_ARGS)
1162{
1163	int disable, error;
1164
1165	disable = hlt_logical_cpus;
1166	error = sysctl_handle_int(oidp, &disable, 0, req);
1167	if (error || !req->newptr)
1168		return (error);
1169
1170	if (disable)
1171		hlt_cpus_mask |= logical_cpus_mask;
1172	else
1173		hlt_cpus_mask &= ~logical_cpus_mask;
1174
1175	if (! hyperthreading_allowed)
1176		hlt_cpus_mask |= hyperthreading_cpus_mask;
1177
1178	if ((hlt_cpus_mask & all_cpus) == all_cpus)
1179		hlt_cpus_mask &= ~(1<<0);
1180
1181	hlt_logical_cpus = disable;
1182	return (error);
1183}
1184
1185static int
1186sysctl_hyperthreading_allowed(SYSCTL_HANDLER_ARGS)
1187{
1188	int allowed, error;
1189
1190	allowed = hyperthreading_allowed;
1191	error = sysctl_handle_int(oidp, &allowed, 0, req);
1192	if (error || !req->newptr)
1193		return (error);
1194
1195	if (allowed)
1196		hlt_cpus_mask &= ~hyperthreading_cpus_mask;
1197	else
1198		hlt_cpus_mask |= hyperthreading_cpus_mask;
1199
1200	if (logical_cpus_mask != 0 &&
1201	    (hlt_cpus_mask & logical_cpus_mask) == logical_cpus_mask)
1202		hlt_logical_cpus = 1;
1203	else
1204		hlt_logical_cpus = 0;
1205
1206	if ((hlt_cpus_mask & all_cpus) == all_cpus)
1207		hlt_cpus_mask &= ~(1<<0);
1208
1209	hyperthreading_allowed = allowed;
1210	return (error);
1211}
1212
1213static void
1214cpu_hlt_setup(void *dummy __unused)
1215{
1216
1217	if (logical_cpus_mask != 0) {
1218		TUNABLE_INT_FETCH("machdep.hlt_logical_cpus",
1219		    &hlt_logical_cpus);
1220		sysctl_ctx_init(&logical_cpu_clist);
1221		SYSCTL_ADD_PROC(&logical_cpu_clist,
1222		    SYSCTL_STATIC_CHILDREN(_machdep), OID_AUTO,
1223		    "hlt_logical_cpus", CTLTYPE_INT|CTLFLAG_RW, 0, 0,
1224		    sysctl_hlt_logical_cpus, "IU", "");
1225		SYSCTL_ADD_UINT(&logical_cpu_clist,
1226		    SYSCTL_STATIC_CHILDREN(_machdep), OID_AUTO,
1227		    "logical_cpus_mask", CTLTYPE_INT|CTLFLAG_RD,
1228		    &logical_cpus_mask, 0, "");
1229
1230		if (hlt_logical_cpus)
1231			hlt_cpus_mask |= logical_cpus_mask;
1232
1233		/*
1234		 * If necessary for security purposes, force
1235		 * hyperthreading off, regardless of the value
1236		 * of hlt_logical_cpus.
1237		 */
1238		if (hyperthreading_cpus_mask) {
1239			TUNABLE_INT_FETCH("machdep.hyperthreading_allowed",
1240			    &hyperthreading_allowed);
1241			SYSCTL_ADD_PROC(&logical_cpu_clist,
1242			    SYSCTL_STATIC_CHILDREN(_machdep), OID_AUTO,
1243			    "hyperthreading_allowed", CTLTYPE_INT|CTLFLAG_RW,
1244			    0, 0, sysctl_hyperthreading_allowed, "IU", "");
1245			if (! hyperthreading_allowed)
1246				hlt_cpus_mask |= hyperthreading_cpus_mask;
1247		}
1248	}
1249}
1250SYSINIT(cpu_hlt, SI_SUB_SMP, SI_ORDER_ANY, cpu_hlt_setup, NULL);
1251
1252int
1253mp_grab_cpu_hlt(void)
1254{
1255	u_int mask = PCPU_GET(cpumask);
1256#ifdef MP_WATCHDOG
1257	u_int cpuid = PCPU_GET(cpuid);
1258#endif
1259	int retval;
1260
1261#ifdef MP_WATCHDOG
1262	ap_watchdog(cpuid);
1263#endif
1264
1265	retval = mask & hlt_cpus_mask;
1266	while (mask & hlt_cpus_mask)
1267		__asm __volatile("sti; hlt" : : : "memory");
1268	return (retval);
1269}
1270