1 /*
2  * Copyright (c) 1996, by Steve Passe
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. The name of the developer may NOT be used to endorse or promote products
11  *    derived from this software without specific prior written permission.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  * $FreeBSD: src/sys/i386/i386/mp_machdep.c,v 1.115.2.15 2003/03/14 21:22:35 jhb Exp $
26  */
27 
28 #include "opt_cpu.h"
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/sysctl.h>
34 #include <sys/malloc.h>
35 #include <sys/memrange.h>
36 #include <sys/cons.h>	/* cngetc() */
37 #include <sys/machintr.h>
38 #include <sys/cpu_topology.h>
39 
40 #include <sys/mplock2.h>
41 
42 #include <vm/vm.h>
43 #include <vm/vm_param.h>
44 #include <vm/pmap.h>
45 #include <vm/vm_kern.h>
46 #include <vm/vm_extern.h>
47 #include <sys/lock.h>
48 #include <vm/vm_map.h>
49 #include <sys/user.h>
50 #ifdef GPROF
51 #include <sys/gmon.h>
52 #endif
53 
54 #include <machine/smp.h>
55 #include <machine_base/apic/apicreg.h>
56 #include <machine/atomic.h>
57 #include <machine/cpufunc.h>
58 #include <machine/cputypes.h>
59 #include <machine_base/apic/lapic.h>
60 #include <machine_base/apic/ioapic.h>
61 #include <machine_base/acpica/acpi_md_cpu.h>
62 #include <machine/psl.h>
63 #include <machine/segments.h>
64 #include <machine/tss.h>
65 #include <machine/specialreg.h>
66 #include <machine/globaldata.h>
67 #include <machine/pmap_inval.h>
68 #include <machine/clock.h>
69 
70 #include <machine/md_var.h>		/* setidt() */
71 #include <machine_base/icu/icu.h>	/* IPIs */
72 #include <machine_base/icu/icu_var.h>
73 #include <machine_base/apic/ioapic_abi.h>
74 #include <machine/intr_machdep.h>	/* IPIs */
75 
76 #define WARMBOOT_TARGET		0
77 #define WARMBOOT_OFF		(KERNBASE + 0x0467)
78 #define WARMBOOT_SEG		(KERNBASE + 0x0469)
79 
80 #define CMOS_REG		(0x70)
81 #define CMOS_DATA		(0x71)
82 #define BIOS_RESET		(0x0f)
83 #define BIOS_WARM		(0x0a)
84 
85 /*
86  * this code MUST be enabled here and in mpboot.s.
87  * it follows the very early stages of AP boot by placing values in CMOS ram.
88  * it NORMALLY will never be needed and thus the primitive method for enabling.
89  *
90  */
91 #if defined(CHECK_POINTS)
92 #define CHECK_READ(A)	 (outb(CMOS_REG, (A)), inb(CMOS_DATA))
93 #define CHECK_WRITE(A,D) (outb(CMOS_REG, (A)), outb(CMOS_DATA, (D)))
94 
95 #define CHECK_INIT(D);				\
96 	CHECK_WRITE(0x34, (D));			\
97 	CHECK_WRITE(0x35, (D));			\
98 	CHECK_WRITE(0x36, (D));			\
99 	CHECK_WRITE(0x37, (D));			\
100 	CHECK_WRITE(0x38, (D));			\
101 	CHECK_WRITE(0x39, (D));
102 
103 #define CHECK_PRINT(S);				\
104 	kprintf("%s: %d, %d, %d, %d, %d, %d\n",	\
105 	   (S),					\
106 	   CHECK_READ(0x34),			\
107 	   CHECK_READ(0x35),			\
108 	   CHECK_READ(0x36),			\
109 	   CHECK_READ(0x37),			\
110 	   CHECK_READ(0x38),			\
111 	   CHECK_READ(0x39));
112 
113 #else				/* CHECK_POINTS */
114 
115 #define CHECK_INIT(D)
116 #define CHECK_PRINT(S)
117 
118 #endif				/* CHECK_POINTS */
119 
120 /*
121  * Values to send to the POST hardware.
122  */
123 #define MP_BOOTADDRESS_POST	0x10
124 #define MP_PROBE_POST		0x11
125 #define MPTABLE_PASS1_POST	0x12
126 
127 #define MP_START_POST		0x13
128 #define MP_ENABLE_POST		0x14
129 #define MPTABLE_PASS2_POST	0x15
130 
131 #define START_ALL_APS_POST	0x16
132 #define INSTALL_AP_TRAMP_POST	0x17
133 #define START_AP_POST		0x18
134 
135 #define MP_ANNOUNCE_POST	0x19
136 
137 /** XXX FIXME: where does this really belong, isa.h/isa.c perhaps? */
138 int	current_postcode;
139 
140 /** XXX FIXME: what system files declare these??? */
141 extern struct region_descriptor r_gdt;
142 
143 extern int nkpt;
144 extern int naps;
145 
146 int64_t tsc0_offset;
147 extern int64_t tsc_offsets[];
148 
149 /* AP uses this during bootstrap.  Do not staticize.  */
150 char *bootSTK;
151 static int bootAP;
152 
153 struct pcb stoppcbs[MAXCPU];
154 
155 extern inthand_t IDTVEC(fast_syscall), IDTVEC(fast_syscall32);
156 
157 /*
158  * Local data and functions.
159  */
160 
161 static u_int	boot_address;
162 static int	mp_finish;
163 static int	mp_finish_lapic;
164 
165 static int	start_all_aps(u_int boot_addr);
166 #if 0
167 static void	install_ap_tramp(u_int boot_addr);
168 #endif
169 static int	start_ap(struct mdglobaldata *gd, u_int boot_addr, int smibest);
170 static int	smitest(void);
171 static void	mp_bsp_simple_setup(void);
172 
173 /* which cpus have been started */
174 static cpumask_t smp_startup_mask = CPUMASK_INITIALIZER_ONLYONE;
175 /* which cpus have lapic been inited */
176 static cpumask_t smp_lapic_mask = CPUMASK_INITIALIZER_ONLYONE;
177 /* which cpus are ready for IPIs etc? */
178 cpumask_t smp_active_mask = CPUMASK_INITIALIZER_ONLYONE;
179 cpumask_t smp_finalize_mask = CPUMASK_INITIALIZER_ONLYONE;
180 
181 SYSCTL_INT(_machdep, OID_AUTO, smp_active, CTLFLAG_RD, &smp_active_mask, 0, "");
182 static u_int	bootMP_size;
183 static u_int	report_invlpg_src;
184 SYSCTL_INT(_machdep, OID_AUTO, report_invlpg_src, CTLFLAG_RW,
185 	&report_invlpg_src, 0, "");
186 static u_int	report_invltlb_src;
187 SYSCTL_INT(_machdep, OID_AUTO, report_invltlb_src, CTLFLAG_RW,
188 	&report_invltlb_src, 0, "");
189 static int	optimized_invltlb;
190 SYSCTL_INT(_machdep, OID_AUTO, optimized_invltlb, CTLFLAG_RW,
191 	&optimized_invltlb, 0, "");
192 static int	all_but_self_ipi_enable = 1;
193 SYSCTL_INT(_machdep, OID_AUTO, all_but_self_ipi_enable, CTLFLAG_RW,
194 	&all_but_self_ipi_enable, 0, "");
195 
196 /* Local data for detecting CPU TOPOLOGY */
197 static int core_bits = 0;
198 static int logical_CPU_bits = 0;
199 
200 
201 /*
202  * Calculate usable address in base memory for AP trampoline code.
203  */
204 u_int
205 mp_bootaddress(u_int basemem)
206 {
207 	POSTCODE(MP_BOOTADDRESS_POST);
208 
209 	bootMP_size = mptramp_end - mptramp_start;
210 	boot_address = trunc_page(basemem * 1024); /* round down to 4k boundary */
211 	if (((basemem * 1024) - boot_address) < bootMP_size)
212 		boot_address -= PAGE_SIZE;	/* not enough, lower by 4k */
213 	/* 3 levels of page table pages */
214 	mptramp_pagetables = boot_address - (PAGE_SIZE * 3);
215 
216 	return mptramp_pagetables;
217 }
218 
219 /*
220  * Print various information about the SMP system hardware and setup.
221  */
222 void
223 mp_announce(void)
224 {
225 	int     x;
226 
227 	POSTCODE(MP_ANNOUNCE_POST);
228 
229 	kprintf("DragonFly/MP: Multiprocessor motherboard\n");
230 	kprintf(" cpu0 (BSP): apic id: %2d\n", CPUID_TO_APICID(0));
231 	for (x = 1; x <= naps; ++x)
232 		kprintf(" cpu%d (AP):  apic id: %2d\n", x, CPUID_TO_APICID(x));
233 
234 	if (!ioapic_enable)
235 		kprintf(" Warning: APIC I/O disabled\n");
236 }
237 
238 /*
239  * AP cpu's call this to sync up protected mode.
240  *
241  * WARNING! %gs is not set up on entry.  This routine sets up %gs.
242  */
243 void
244 init_secondary(void)
245 {
246 	int	gsel_tss;
247 	int	x, myid = bootAP;
248 	u_int64_t msr, cr0;
249 	struct mdglobaldata *md;
250 	struct privatespace *ps;
251 
252 	ps = CPU_prvspace[myid];
253 
254 	gdt_segs[GPROC0_SEL].ssd_base =
255 		(long) &ps->mdglobaldata.gd_common_tss;
256 	ps->mdglobaldata.mi.gd_prvspace = ps;
257 
258 	/* We fill the 32-bit segment descriptors */
259 	for (x = 0; x < NGDT; x++) {
260 		if (x != GPROC0_SEL && x != (GPROC0_SEL + 1))
261 			ssdtosd(&gdt_segs[x], &gdt[myid * NGDT + x]);
262 	}
263 	/* And now a 64-bit one */
264 	ssdtosyssd(&gdt_segs[GPROC0_SEL],
265 	    (struct system_segment_descriptor *)&gdt[myid * NGDT + GPROC0_SEL]);
266 
267 	r_gdt.rd_limit = NGDT * sizeof(gdt[0]) - 1;
268 	r_gdt.rd_base = (long) &gdt[myid * NGDT];
269 	lgdt(&r_gdt);			/* does magic intra-segment return */
270 
271 	/* lgdt() destroys the GSBASE value, so we load GSBASE after lgdt() */
272 	wrmsr(MSR_FSBASE, 0);		/* User value */
273 	wrmsr(MSR_GSBASE, (u_int64_t)ps);
274 	wrmsr(MSR_KGSBASE, 0);		/* XXX User value while we're in the kernel */
275 
276 	lidt(&r_idt_arr[mdcpu->mi.gd_cpuid]);
277 
278 #if 0
279 	lldt(_default_ldt);
280 	mdcpu->gd_currentldt = _default_ldt;
281 #endif
282 
283 	gsel_tss = GSEL(GPROC0_SEL, SEL_KPL);
284 	gdt[myid * NGDT + GPROC0_SEL].sd_type = SDT_SYSTSS;
285 
286 	md = mdcpu;	/* loaded through %gs:0 (mdglobaldata.mi.gd_prvspace)*/
287 
288 	md->gd_common_tss.tss_rsp0 = 0;	/* not used until after switch */
289 #if 0 /* JG XXX */
290 	md->gd_common_tss.tss_ioopt = (sizeof md->gd_common_tss) << 16;
291 #endif
292 	md->gd_tss_gdt = &gdt[myid * NGDT + GPROC0_SEL];
293 	md->gd_common_tssd = *md->gd_tss_gdt;
294 
295 	/* double fault stack */
296 	md->gd_common_tss.tss_ist1 =
297 		(long)&md->mi.gd_prvspace->idlestack[
298 			sizeof(md->mi.gd_prvspace->idlestack)];
299 
300 	ltr(gsel_tss);
301 
302 	/*
303 	 * Set to a known state:
304 	 * Set by mpboot.s: CR0_PG, CR0_PE
305 	 * Set by cpu_setregs: CR0_NE, CR0_MP, CR0_TS, CR0_WP, CR0_AM
306 	 */
307 	cr0 = rcr0();
308 	cr0 &= ~(CR0_CD | CR0_NW | CR0_EM);
309 	load_cr0(cr0);
310 
311 	/* Set up the fast syscall stuff */
312 	msr = rdmsr(MSR_EFER) | EFER_SCE;
313 	wrmsr(MSR_EFER, msr);
314 	wrmsr(MSR_LSTAR, (u_int64_t)IDTVEC(fast_syscall));
315 	wrmsr(MSR_CSTAR, (u_int64_t)IDTVEC(fast_syscall32));
316 	msr = ((u_int64_t)GSEL(GCODE_SEL, SEL_KPL) << 32) |
317 	      ((u_int64_t)GSEL(GUCODE32_SEL, SEL_UPL) << 48);
318 	wrmsr(MSR_STAR, msr);
319 	wrmsr(MSR_SF_MASK, PSL_NT|PSL_T|PSL_I|PSL_C|PSL_D|PSL_IOPL);
320 
321 	pmap_set_opt();		/* PSE/4MB pages, etc */
322 	pmap_init_pat();	/* Page Attribute Table */
323 
324 	/* set up CPU registers and state */
325 	cpu_setregs();
326 
327 	/* set up SSE/NX registers */
328 	initializecpu(myid);
329 
330 	/* set up FPU state on the AP */
331 	npxinit();
332 
333 	/* disable the APIC, just to be SURE */
334 	lapic->svr &= ~APIC_SVR_ENABLE;
335 }
336 
337 /*******************************************************************
338  * local functions and data
339  */
340 
341 /*
342  * Start the SMP system
343  */
344 static void
345 mp_start_aps(void *dummy __unused)
346 {
347 	if (lapic_enable) {
348 		/* start each Application Processor */
349 		start_all_aps(boot_address);
350 	} else {
351 		mp_bsp_simple_setup();
352 	}
353 }
354 SYSINIT(startaps, SI_BOOT2_START_APS, SI_ORDER_FIRST, mp_start_aps, NULL);
355 
356 /*
357  * start each AP in our list
358  */
359 static int
360 start_all_aps(u_int boot_addr)
361 {
362 	vm_offset_t va = boot_address + KERNBASE;
363 	u_int64_t *pt4, *pt3, *pt2;
364 	int	pssize;
365 	int     x, i;
366 	int	shift;
367 	int	smicount;
368 	int	smibest;
369 	int	smilast;
370 	u_char  mpbiosreason;
371 	u_long  mpbioswarmvec;
372 	struct mdglobaldata *gd;
373 	struct privatespace *ps;
374 	size_t ipiq_size;
375 
376 	POSTCODE(START_ALL_APS_POST);
377 
378 	/* install the AP 1st level boot code */
379 	pmap_kenter(va, boot_address);
380 	cpu_invlpg((void *)va);		/* JG XXX */
381 	bcopy(mptramp_start, (void *)va, bootMP_size);
382 
383 	/* Locate the page tables, they'll be below the trampoline */
384 	pt4 = (u_int64_t *)(uintptr_t)(mptramp_pagetables + KERNBASE);
385 	pt3 = pt4 + (PAGE_SIZE) / sizeof(u_int64_t);
386 	pt2 = pt3 + (PAGE_SIZE) / sizeof(u_int64_t);
387 
388 	/* Create the initial 1GB replicated page tables */
389 	for (i = 0; i < 512; i++) {
390 		/* Each slot of the level 4 pages points to the same level 3 page */
391 		pt4[i] = (u_int64_t)(uintptr_t)(mptramp_pagetables + PAGE_SIZE);
392 		pt4[i] |= kernel_pmap.pmap_bits[PG_V_IDX] |
393 		    kernel_pmap.pmap_bits[PG_RW_IDX] |
394 		    kernel_pmap.pmap_bits[PG_U_IDX];
395 
396 		/* Each slot of the level 3 pages points to the same level 2 page */
397 		pt3[i] = (u_int64_t)(uintptr_t)(mptramp_pagetables + (2 * PAGE_SIZE));
398 		pt3[i] |= kernel_pmap.pmap_bits[PG_V_IDX] |
399 		    kernel_pmap.pmap_bits[PG_RW_IDX] |
400 		    kernel_pmap.pmap_bits[PG_U_IDX];
401 
402 		/* The level 2 page slots are mapped with 2MB pages for 1GB. */
403 		pt2[i] = i * (2 * 1024 * 1024);
404 		pt2[i] |= kernel_pmap.pmap_bits[PG_V_IDX] |
405 		    kernel_pmap.pmap_bits[PG_RW_IDX] |
406 		    kernel_pmap.pmap_bits[PG_PS_IDX] |
407 		    kernel_pmap.pmap_bits[PG_U_IDX];
408 	}
409 
410 	/* save the current value of the warm-start vector */
411 	mpbioswarmvec = *((u_int32_t *) WARMBOOT_OFF);
412 	outb(CMOS_REG, BIOS_RESET);
413 	mpbiosreason = inb(CMOS_DATA);
414 
415 	/* setup a vector to our boot code */
416 	*((volatile u_short *) WARMBOOT_OFF) = WARMBOOT_TARGET;
417 	*((volatile u_short *) WARMBOOT_SEG) = (boot_address >> 4);
418 	outb(CMOS_REG, BIOS_RESET);
419 	outb(CMOS_DATA, BIOS_WARM);	/* 'warm-start' */
420 
421 	/*
422 	 * If we have a TSC we can figure out the SMI interrupt rate.
423 	 * The SMI does not necessarily use a constant rate.  Spend
424 	 * up to 250ms trying to figure it out.
425 	 */
426 	smibest = 0;
427 	if (cpu_feature & CPUID_TSC) {
428 		set_apic_timer(275000);
429 		smilast = read_apic_timer();
430 		for (x = 0; x < 20 && read_apic_timer(); ++x) {
431 			smicount = smitest();
432 			if (smibest == 0 || smilast - smicount < smibest)
433 				smibest = smilast - smicount;
434 			smilast = smicount;
435 		}
436 		if (smibest > 250000)
437 			smibest = 0;
438 		if (smibest) {
439 			smibest = smibest * (int64_t)1000000 /
440 				  get_apic_timer_frequency();
441 		}
442 	}
443 	if (smibest)
444 		kprintf("SMI Frequency (worst case): %d Hz (%d us)\n",
445 			1000000 / smibest, smibest);
446 
447 	/* start each AP */
448 	for (x = 1; x <= naps; ++x) {
449 		/* This is a bit verbose, it will go away soon.  */
450 
451 		pssize = sizeof(struct privatespace);
452 		ps = (void *)kmem_alloc(&kernel_map, pssize, VM_SUBSYS_GD);
453 		CPU_prvspace[x] = ps;
454 #if 0
455 		kprintf("ps %d %p %d\n", x, ps, pssize);
456 #endif
457 		bzero(ps, pssize);
458 		gd = &ps->mdglobaldata;
459 		gd->mi.gd_prvspace = ps;
460 
461 		/* prime data page for it to use */
462 		mi_gdinit(&gd->mi, x);
463 		cpu_gdinit(gd, x);
464 		ipiq_size = sizeof(struct lwkt_ipiq) * (naps + 1);
465 		gd->mi.gd_ipiq = (void *)kmem_alloc(&kernel_map, ipiq_size,
466 						    VM_SUBSYS_IPIQ);
467 		bzero(gd->mi.gd_ipiq, ipiq_size);
468 
469 		gd->gd_acpi_id = CPUID_TO_ACPIID(gd->mi.gd_cpuid);
470 
471 		/* setup a vector to our boot code */
472 		*((volatile u_short *) WARMBOOT_OFF) = WARMBOOT_TARGET;
473 		*((volatile u_short *) WARMBOOT_SEG) = (boot_addr >> 4);
474 		outb(CMOS_REG, BIOS_RESET);
475 		outb(CMOS_DATA, BIOS_WARM);	/* 'warm-start' */
476 
477 		/*
478 		 * Setup the AP boot stack
479 		 */
480 		bootSTK = &ps->idlestack[UPAGES * PAGE_SIZE - PAGE_SIZE];
481 		bootAP = x;
482 
483 		/* attempt to start the Application Processor */
484 		CHECK_INIT(99);	/* setup checkpoints */
485 		if (!start_ap(gd, boot_addr, smibest)) {
486 			kprintf("\nAP #%d (PHY# %d) failed!\n",
487 				x, CPUID_TO_APICID(x));
488 			CHECK_PRINT("trace");	/* show checkpoints */
489 			/* better panic as the AP may be running loose */
490 			kprintf("panic y/n? [y] ");
491 			cnpoll(TRUE);
492 			if (cngetc() != 'n')
493 				panic("bye-bye");
494 			cnpoll(FALSE);
495 		}
496 		CHECK_PRINT("trace");		/* show checkpoints */
497 	}
498 
499 	/* set ncpus to 1 + highest logical cpu.  Not all may have come up */
500 	ncpus = x;
501 
502 	/* ncpus2 -- ncpus rounded down to the nearest power of 2 */
503 	for (shift = 0; (1 << shift) <= ncpus; ++shift)
504 		;
505 	--shift;
506 	ncpus2_shift = shift;
507 	ncpus2 = 1 << shift;
508 	ncpus2_mask = ncpus2 - 1;
509 
510 	/* ncpus_fit -- ncpus rounded up to the nearest power of 2 */
511 	if ((1 << shift) < ncpus)
512 		++shift;
513 	ncpus_fit = 1 << shift;
514 	ncpus_fit_mask = ncpus_fit - 1;
515 
516 	/* build our map of 'other' CPUs */
517 	mycpu->gd_other_cpus = smp_startup_mask;
518 	CPUMASK_NANDBIT(mycpu->gd_other_cpus, mycpu->gd_cpuid);
519 
520 	gd = (struct mdglobaldata *)mycpu;
521 	gd->gd_acpi_id = CPUID_TO_ACPIID(mycpu->gd_cpuid);
522 
523 	ipiq_size = sizeof(struct lwkt_ipiq) * ncpus;
524 	mycpu->gd_ipiq = (void *)kmem_alloc(&kernel_map, ipiq_size,
525 					    VM_SUBSYS_IPIQ);
526 	bzero(mycpu->gd_ipiq, ipiq_size);
527 
528 	/* restore the warmstart vector */
529 	*(u_long *) WARMBOOT_OFF = mpbioswarmvec;
530 	outb(CMOS_REG, BIOS_RESET);
531 	outb(CMOS_DATA, mpbiosreason);
532 
533 	/*
534 	 * NOTE!  The idlestack for the BSP was setup by locore.  Finish
535 	 * up, clean out the P==V mapping we did earlier.
536 	 */
537 	pmap_set_opt();
538 
539 	/*
540 	 * Wait all APs to finish initializing LAPIC
541 	 */
542 	if (bootverbose)
543 		kprintf("SMP: Waiting APs LAPIC initialization\n");
544 	if (cpu_feature & CPUID_TSC)
545 		tsc0_offset = rdtsc();
546 	tsc_offsets[0] = 0;
547 	mp_finish_lapic = 1;
548 	rel_mplock();
549 
550 	while (CPUMASK_CMPMASKNEQ(smp_lapic_mask, smp_startup_mask)) {
551 		cpu_pause();
552 		cpu_lfence();
553 		if (cpu_feature & CPUID_TSC)
554 			tsc0_offset = rdtsc();
555 	}
556 	while (try_mplock() == 0) {
557 		cpu_pause();
558 		cpu_lfence();
559 	}
560 
561 	/* number of APs actually started */
562 	return ncpus - 1;
563 }
564 
565 
566 /*
567  * load the 1st level AP boot code into base memory.
568  */
569 
570 /* targets for relocation */
571 extern void bigJump(void);
572 extern void bootCodeSeg(void);
573 extern void bootDataSeg(void);
574 extern void MPentry(void);
575 extern u_int MP_GDT;
576 extern u_int mp_gdtbase;
577 
578 #if 0
579 
580 static void
581 install_ap_tramp(u_int boot_addr)
582 {
583 	int     x;
584 	int     size = *(int *) ((u_long) & bootMP_size);
585 	u_char *src = (u_char *) ((u_long) bootMP);
586 	u_char *dst = (u_char *) boot_addr + KERNBASE;
587 	u_int   boot_base = (u_int) bootMP;
588 	u_int8_t *dst8;
589 	u_int16_t *dst16;
590 	u_int32_t *dst32;
591 
592 	POSTCODE(INSTALL_AP_TRAMP_POST);
593 
594 	for (x = 0; x < size; ++x)
595 		*dst++ = *src++;
596 
597 	/*
598 	 * modify addresses in code we just moved to basemem. unfortunately we
599 	 * need fairly detailed info about mpboot.s for this to work.  changes
600 	 * to mpboot.s might require changes here.
601 	 */
602 
603 	/* boot code is located in KERNEL space */
604 	dst = (u_char *) boot_addr + KERNBASE;
605 
606 	/* modify the lgdt arg */
607 	dst32 = (u_int32_t *) (dst + ((u_int) & mp_gdtbase - boot_base));
608 	*dst32 = boot_addr + ((u_int) & MP_GDT - boot_base);
609 
610 	/* modify the ljmp target for MPentry() */
611 	dst32 = (u_int32_t *) (dst + ((u_int) bigJump - boot_base) + 1);
612 	*dst32 = ((u_int) MPentry - KERNBASE);
613 
614 	/* modify the target for boot code segment */
615 	dst16 = (u_int16_t *) (dst + ((u_int) bootCodeSeg - boot_base));
616 	dst8 = (u_int8_t *) (dst16 + 1);
617 	*dst16 = (u_int) boot_addr & 0xffff;
618 	*dst8 = ((u_int) boot_addr >> 16) & 0xff;
619 
620 	/* modify the target for boot data segment */
621 	dst16 = (u_int16_t *) (dst + ((u_int) bootDataSeg - boot_base));
622 	dst8 = (u_int8_t *) (dst16 + 1);
623 	*dst16 = (u_int) boot_addr & 0xffff;
624 	*dst8 = ((u_int) boot_addr >> 16) & 0xff;
625 }
626 
627 #endif
628 
629 /*
630  * This function starts the AP (application processor) identified
631  * by the APIC ID 'physicalCpu'.  It does quite a "song and dance"
632  * to accomplish this.  This is necessary because of the nuances
633  * of the different hardware we might encounter.  It ain't pretty,
634  * but it seems to work.
635  *
636  * NOTE: eventually an AP gets to ap_init(), which is called just
637  * before the AP goes into the LWKT scheduler's idle loop.
638  */
639 static int
640 start_ap(struct mdglobaldata *gd, u_int boot_addr, int smibest)
641 {
642 	int     physical_cpu;
643 	int     vector;
644 	u_long  icr_lo, icr_hi;
645 
646 	POSTCODE(START_AP_POST);
647 
648 	/* get the PHYSICAL APIC ID# */
649 	physical_cpu = CPUID_TO_APICID(gd->mi.gd_cpuid);
650 
651 	/* calculate the vector */
652 	vector = (boot_addr >> 12) & 0xff;
653 
654 	/* We don't want anything interfering */
655 	cpu_disable_intr();
656 
657 	/* Make sure the target cpu sees everything */
658 	wbinvd();
659 
660 	/*
661 	 * Try to detect when a SMI has occurred, wait up to 200ms.
662 	 *
663 	 * If a SMI occurs during an AP reset but before we issue
664 	 * the STARTUP command, the AP may brick.  To work around
665 	 * this problem we hold off doing the AP startup until
666 	 * after we have detected the SMI.  Hopefully another SMI
667 	 * will not occur before we finish the AP startup.
668 	 *
669 	 * Retries don't seem to help.  SMIs have a window of opportunity
670 	 * and if USB->legacy keyboard emulation is enabled in the BIOS
671 	 * the interrupt rate can be quite high.
672 	 *
673 	 * NOTE: Don't worry about the L1 cache load, it might bloat
674 	 *	 ldelta a little but ndelta will be so huge when the SMI
675 	 *	 occurs the detection logic will still work fine.
676 	 */
677 	if (smibest) {
678 		set_apic_timer(200000);
679 		smitest();
680 	}
681 
682 	/*
683 	 * first we do an INIT/RESET IPI this INIT IPI might be run, reseting
684 	 * and running the target CPU. OR this INIT IPI might be latched (P5
685 	 * bug), CPU waiting for STARTUP IPI. OR this INIT IPI might be
686 	 * ignored.
687 	 *
688 	 * see apic/apicreg.h for icr bit definitions.
689 	 *
690 	 * TIME CRITICAL CODE, DO NOT DO ANY KPRINTFS IN THE HOT PATH.
691 	 */
692 
693 	/*
694 	 * Setup the address for the target AP.  We can setup
695 	 * icr_hi once and then just trigger operations with
696 	 * icr_lo.
697 	 */
698 	icr_hi = lapic->icr_hi & ~APIC_ID_MASK;
699 	icr_hi |= (physical_cpu << 24);
700 	icr_lo = lapic->icr_lo & 0xfff00000;
701 	lapic->icr_hi = icr_hi;
702 
703 	/*
704 	 * Do an INIT IPI: assert RESET
705 	 *
706 	 * Use edge triggered mode to assert INIT
707 	 */
708 	lapic->icr_lo = icr_lo | 0x00004500;
709 	while (lapic->icr_lo & APIC_DELSTAT_MASK)
710 		 /* spin */ ;
711 
712 	/*
713 	 * The spec calls for a 10ms delay but we may have to use a
714 	 * MUCH lower delay to avoid bricking an AP due to a fast SMI
715 	 * interrupt.  We have other loops here too and dividing by 2
716 	 * doesn't seem to be enough even after subtracting 350us,
717 	 * so we divide by 4.
718 	 *
719 	 * Our minimum delay is 150uS, maximum is 10ms.  If no SMI
720 	 * interrupt was detected we use the full 10ms.
721 	 */
722 	if (smibest == 0)
723 		u_sleep(10000);
724 	else if (smibest < 150 * 4 + 350)
725 		u_sleep(150);
726 	else if ((smibest - 350) / 4 < 10000)
727 		u_sleep((smibest - 350) / 4);
728 	else
729 		u_sleep(10000);
730 
731 	/*
732 	 * Do an INIT IPI: deassert RESET
733 	 *
734 	 * Use level triggered mode to deassert.  It is unclear
735 	 * why we need to do this.
736 	 */
737 	lapic->icr_lo = icr_lo | 0x00008500;
738 	while (lapic->icr_lo & APIC_DELSTAT_MASK)
739 		 /* spin */ ;
740 	u_sleep(150);				/* wait 150us */
741 
742 	/*
743 	 * Next we do a STARTUP IPI: the previous INIT IPI might still be
744 	 * latched, (P5 bug) this 1st STARTUP would then terminate
745 	 * immediately, and the previously started INIT IPI would continue. OR
746 	 * the previous INIT IPI has already run. and this STARTUP IPI will
747 	 * run. OR the previous INIT IPI was ignored. and this STARTUP IPI
748 	 * will run.
749 	 */
750 	lapic->icr_lo = icr_lo | 0x00000600 | vector;
751 	while (lapic->icr_lo & APIC_DELSTAT_MASK)
752 		 /* spin */ ;
753 	u_sleep(200);		/* wait ~200uS */
754 
755 	/*
756 	 * Finally we do a 2nd STARTUP IPI: this 2nd STARTUP IPI should run IF
757 	 * the previous STARTUP IPI was cancelled by a latched INIT IPI. OR
758 	 * this STARTUP IPI will be ignored, as only ONE STARTUP IPI is
759 	 * recognized after hardware RESET or INIT IPI.
760 	 */
761 	lapic->icr_lo = icr_lo | 0x00000600 | vector;
762 	while (lapic->icr_lo & APIC_DELSTAT_MASK)
763 		 /* spin */ ;
764 
765 	/* Resume normal operation */
766 	cpu_enable_intr();
767 
768 	/* wait for it to start, see ap_init() */
769 	set_apic_timer(5000000);/* == 5 seconds */
770 	while (read_apic_timer()) {
771 		if (CPUMASK_TESTBIT(smp_startup_mask, gd->mi.gd_cpuid))
772 			return 1;	/* return SUCCESS */
773 	}
774 
775 	return 0;		/* return FAILURE */
776 }
777 
778 static
779 int
780 smitest(void)
781 {
782 	int64_t	ltsc;
783 	int64_t	ntsc;
784 	int64_t	ldelta;
785 	int64_t	ndelta;
786 	int count;
787 
788 	ldelta = 0;
789 	ndelta = 0;
790 	while (read_apic_timer()) {
791 		ltsc = rdtsc();
792 		for (count = 0; count < 100; ++count)
793 			ntsc = rdtsc();	/* force loop to occur */
794 		if (ldelta) {
795 			ndelta = ntsc - ltsc;
796 			if (ldelta > ndelta)
797 				ldelta = ndelta;
798 			if (ndelta > ldelta * 2)
799 				break;
800 		} else {
801 			ldelta = ntsc - ltsc;
802 		}
803 	}
804 	return(read_apic_timer());
805 }
806 
807 /*
808  * Synchronously flush the TLB on all other CPU's.  The current cpu's
809  * TLB is not flushed.  If the caller wishes to flush the current cpu's
810  * TLB the caller must call cpu_invltlb() in addition to smp_invltlb().
811  *
812  * This routine may be called concurrently from multiple cpus.  When this
813  * happens, smp_invltlb() can wind up sticking around in the confirmation
814  * while() loop at the end as additional cpus are added to the global
815  * cpumask, until they are acknowledged by another IPI.
816  *
817  * NOTE: If for some reason we were unable to start all cpus we cannot
818  *	 safely use broadcast IPIs.
819  */
820 
821 cpumask_t smp_smurf_mask;
822 static cpumask_t smp_invltlb_mask;
823 #define LOOPRECOVER
824 #ifdef LOOPMASK_IN
825 cpumask_t smp_in_mask;
826 #endif
827 cpumask_t smp_invmask;
828 extern cpumask_t smp_idleinvl_mask;
829 extern cpumask_t smp_idleinvl_reqs;
830 
831 /*
832  * Atomically OR bits in *mask to smp_smurf_mask.  Adjust *mask to remove
833  * bits that do not need to be IPId.  These bits are still part of the command,
834  * but the target cpus have already been signalled and do not need to be
835  * sigalled again.
836  */
837 #include <sys/spinlock.h>
838 #include <sys/spinlock2.h>
839 
840 static __noinline
841 void
842 smp_smurf_fetchset(cpumask_t *mask)
843 {
844 	cpumask_t omask;
845 	int i;
846 	__uint64_t obits;
847 	__uint64_t nbits;
848 
849 	i = 0;
850 	while (i < CPUMASK_ELEMENTS) {
851 		obits = smp_smurf_mask.ary[i];
852 		cpu_ccfence();
853 		nbits = obits | mask->ary[i];
854 		if (atomic_cmpset_long(&smp_smurf_mask.ary[i], obits, nbits)) {
855 			omask.ary[i] = obits;
856 			++i;
857 		}
858 	}
859 	CPUMASK_NANDMASK(*mask, omask);
860 }
861 
862 /*
863  * This is a mechanism which guarantees that cpu_invltlb() will be executed
864  * on idle cpus without having to signal or wake them up.  The invltlb will be
865  * executed when they wake up, prior to any scheduling or interrupt thread.
866  *
867  * (*mask) is modified to remove the cpus we successfully negotiate this
868  * function with.  This function may only be used with semi-synchronous
869  * commands (typically invltlb's or semi-synchronous invalidations which
870  * are usually associated only with kernel memory).
871  */
872 void
873 smp_smurf_idleinvlclr(cpumask_t *mask)
874 {
875 	if (optimized_invltlb) {
876 		ATOMIC_CPUMASK_ORMASK(smp_idleinvl_reqs, *mask);
877 		/* cpu_lfence() not needed */
878 		CPUMASK_NANDMASK(*mask, smp_idleinvl_mask);
879 	}
880 }
881 
882 /*
883  * Issue cpu_invltlb() across all cpus except the current cpu.
884  *
885  * This function will arrange to avoid idle cpus, but still gurantee that
886  * invltlb is run on them when they wake up prior to any scheduling or
887  * nominal interrupt.
888  */
889 void
890 smp_invltlb(void)
891 {
892 	struct mdglobaldata *md = mdcpu;
893 	cpumask_t mask;
894 	unsigned long rflags;
895 #ifdef LOOPRECOVER
896 	uint64_t tsc_base = rdtsc();
897 	int repeats = 0;
898 #endif
899 
900 	if (report_invltlb_src > 0) {
901 		if (--report_invltlb_src <= 0)
902 			print_backtrace(8);
903 	}
904 
905 	/*
906 	 * Disallow normal interrupts, set all active cpus except our own
907 	 * in the global smp_invltlb_mask.
908 	 */
909 	++md->mi.gd_cnt.v_smpinvltlb;
910 	crit_enter_gd(&md->mi);
911 
912 	/*
913 	 * Bits we want to set in smp_invltlb_mask.  We do not want to signal
914 	 * our own cpu.  Also try to remove bits associated with idle cpus
915 	 * that we can flag for auto-invltlb.
916 	 */
917 	mask = smp_active_mask;
918 	CPUMASK_NANDBIT(mask, md->mi.gd_cpuid);
919 	smp_smurf_idleinvlclr(&mask);
920 
921 	rflags = read_rflags();
922 	cpu_disable_intr();
923 	ATOMIC_CPUMASK_ORMASK(smp_invltlb_mask, mask);
924 
925 	/*
926 	 * IPI non-idle cpus represented by mask.  The omask calculation
927 	 * removes cpus from the mask which already have a Xinvltlb IPI
928 	 * pending (avoid double-queueing the IPI).
929 	 *
930 	 * We must disable real interrupts when setting the smurf flags or
931 	 * we might race a XINVLTLB before we manage to send the ipi's for
932 	 * the bits we set.
933 	 *
934 	 * NOTE: We are not signalling ourselves, mask already does NOT
935 	 * include our own cpu.
936 	 */
937 	smp_smurf_fetchset(&mask);
938 
939 	/*
940 	 * Issue the IPI.  Note that the XINVLTLB IPI runs regardless of
941 	 * the critical section count on the target cpus.
942 	 */
943 	CPUMASK_ORMASK(mask, md->mi.gd_cpumask);
944 	if (all_but_self_ipi_enable &&
945 	    CPUMASK_CMPMASKEQ(smp_startup_mask, mask)) {
946 		all_but_self_ipi(XINVLTLB_OFFSET);
947 	} else {
948 		CPUMASK_NANDMASK(mask, md->mi.gd_cpumask);
949 		selected_apic_ipi(mask, XINVLTLB_OFFSET, APIC_DELMODE_FIXED);
950 	}
951 
952 	/*
953 	 * Wait for acknowledgement by all cpus.  smp_inval_intr() will
954 	 * temporarily enable interrupts to avoid deadlocking the lapic,
955 	 * and will also handle running cpu_invltlb() and remote invlpg
956 	 * command son our cpu if some other cpu requests it of us.
957 	 *
958 	 * WARNING! I originally tried to implement this as a hard loop
959 	 *	    checking only smp_invltlb_mask (and issuing a local
960 	 *	    cpu_invltlb() if requested), with interrupts enabled
961 	 *	    and without calling smp_inval_intr().  This DID NOT WORK.
962 	 *	    It resulted in weird races where smurf bits would get
963 	 *	    cleared without any action being taken.
964 	 */
965 	smp_inval_intr();
966 	CPUMASK_ASSZERO(mask);
967 	while (CPUMASK_CMPMASKNEQ(smp_invltlb_mask, mask)) {
968 		smp_inval_intr();
969 		cpu_pause();
970 #ifdef LOOPRECOVER
971 		if (tsc_frequency && rdtsc() - tsc_base > tsc_frequency) {
972 			kprintf("smp_invltlb %d: waited too long %08jx "
973 				"dbg=%08jx %08jx\n",
974 				md->mi.gd_cpuid,
975 				smp_invltlb_mask.ary[0],
976 				smp_idleinvl_mask.ary[0],
977 				smp_idleinvl_reqs.ary[0]);
978 			mdcpu->gd_xinvaltlb = 0;
979 			ATOMIC_CPUMASK_NANDMASK(smp_smurf_mask,
980 						smp_invltlb_mask);
981 			smp_invlpg(&smp_active_mask);
982 			tsc_base = rdtsc();
983 			if (++repeats > 10) {
984 				kprintf("smp_invltlb: giving up\n");
985 				CPUMASK_ASSZERO(smp_invltlb_mask);
986 			}
987 		}
988 #endif
989 	}
990 	write_rflags(rflags);
991 	crit_exit_gd(&md->mi);
992 }
993 
994 /*
995  * Called from a critical section with interrupts hard-disabled.
996  * This function issues an XINVLTLB IPI and then executes any pending
997  * command on the current cpu before returning.
998  */
999 void
1000 smp_invlpg(cpumask_t *cmdmask)
1001 {
1002 	struct mdglobaldata *md = mdcpu;
1003 	cpumask_t mask;
1004 
1005 	if (report_invlpg_src > 0) {
1006 		if (--report_invlpg_src <= 0)
1007 			print_backtrace(8);
1008 	}
1009 
1010 	/*
1011 	 * Disallow normal interrupts, set all active cpus in the pmap,
1012 	 * plus our own for completion processing (it might or might not
1013 	 * be part of the set).
1014 	 */
1015 	mask = smp_active_mask;
1016 	CPUMASK_ANDMASK(mask, *cmdmask);
1017 	CPUMASK_ORMASK(mask, md->mi.gd_cpumask);
1018 
1019 	/*
1020 	 * Avoid double-queuing IPIs, which can deadlock us.  We must disable
1021 	 * real interrupts when setting the smurf flags or we might race a
1022 	 * XINVLTLB before we manage to send the ipi's for the bits we set.
1023 	 *
1024 	 * NOTE: We might be including our own cpu in the smurf mask.
1025 	 */
1026 	smp_smurf_fetchset(&mask);
1027 
1028 	/*
1029 	 * Issue the IPI.  Note that the XINVLTLB IPI runs regardless of
1030 	 * the critical section count on the target cpus.
1031 	 *
1032 	 * We do not include our own cpu when issuing the IPI.
1033 	 */
1034 	if (all_but_self_ipi_enable &&
1035 	    CPUMASK_CMPMASKEQ(smp_startup_mask, mask)) {
1036 		all_but_self_ipi(XINVLTLB_OFFSET);
1037 	} else {
1038 		CPUMASK_NANDMASK(mask, md->mi.gd_cpumask);
1039 		selected_apic_ipi(mask, XINVLTLB_OFFSET, APIC_DELMODE_FIXED);
1040 	}
1041 
1042 	/*
1043 	 * This will synchronously wait for our command to complete,
1044 	 * as well as process commands from other cpus.  It also handles
1045 	 * reentrancy.
1046 	 *
1047 	 * (interrupts are disabled and we are in a critical section here)
1048 	 */
1049 	smp_inval_intr();
1050 }
1051 
1052 void
1053 smp_sniff(void)
1054 {
1055 	globaldata_t gd = mycpu;
1056 	int dummy;
1057 
1058 	/*
1059 	 * Ignore all_but_self_ipi_enable here and just use it.
1060 	 */
1061 	all_but_self_ipi(XSNIFF_OFFSET);
1062 	gd->gd_sample_pc = smp_sniff;
1063 	gd->gd_sample_sp = &dummy;
1064 }
1065 
1066 /*
1067  * Called from Xinvltlb assembly with interrupts hard-disabled and in a
1068  * critical section.  gd_intr_nesting_level may or may not be bumped
1069  * depending on entry.
1070  *
1071  * THIS CODE IS INTENDED TO EXPLICITLY IGNORE THE CRITICAL SECTION COUNT.
1072  * THAT IS, THE INTERRUPT IS INTENDED TO FUNCTION EVEN WHEN MAINLINE CODE
1073  * IS IN A CRITICAL SECTION.
1074  */
1075 void
1076 smp_inval_intr(void)
1077 {
1078 	struct mdglobaldata *md = mdcpu;
1079 	cpumask_t cpumask;
1080 #ifdef LOOPRECOVER
1081 	uint64_t tsc_base = rdtsc();
1082 #endif
1083 
1084 #if 0
1085 	/*
1086 	 * The idle code is in a critical section, but that doesn't stop
1087 	 * Xinvltlb from executing, so deal with the race which can occur
1088 	 * in that situation.  Otherwise r-m-w operations by pmap_inval_intr()
1089 	 * may have problems.
1090 	 */
1091 	if (ATOMIC_CPUMASK_TESTANDCLR(smp_idleinvl_reqs, md->mi.gd_cpuid)) {
1092 		ATOMIC_CPUMASK_NANDBIT(smp_invltlb_mask, md->mi.gd_cpuid);
1093 		cpu_invltlb();
1094 		cpu_mfence();
1095 	}
1096 #endif
1097 
1098 	/*
1099 	 * This is a real mess.  I'd like to just leave interrupts disabled
1100 	 * but it can cause the lapic to deadlock if too many interrupts queue
1101 	 * to it, due to the idiotic design of the lapic.  So instead we have
1102 	 * to enter a critical section so normal interrupts are made pending
1103 	 * and track whether this one was reentered.
1104 	 */
1105 	if (md->gd_xinvaltlb) {		/* reentrant on cpu */
1106 		md->gd_xinvaltlb = 2;
1107 		return;
1108 	}
1109 	md->gd_xinvaltlb = 1;
1110 
1111 	/*
1112 	 * Check only those cpus with active Xinvl* commands pending.
1113 	 *
1114 	 * We are going to enable interrupts so make sure we are in a
1115 	 * critical section.  This is necessary to avoid deadlocking
1116 	 * the lapic and to ensure that we execute our commands prior to
1117 	 * any nominal interrupt or preemption.
1118 	 *
1119 	 * WARNING! It is very important that we only clear out but in
1120 	 *	    smp_smurf_mask once for each interrupt we take.  In
1121 	 *	    this case, we clear it on initial entry and only loop
1122 	 *	    on the reentrancy detect (caused by another interrupt).
1123 	 */
1124 	cpumask = smp_invmask;
1125 loop:
1126 	cpu_enable_intr();
1127 #ifdef LOOPMASK_IN
1128 	ATOMIC_CPUMASK_ORBIT(smp_in_mask, md->mi.gd_cpuid);
1129 #endif
1130 	ATOMIC_CPUMASK_NANDBIT(smp_smurf_mask, md->mi.gd_cpuid);
1131 
1132 	/*
1133 	 * Specific page request(s), and we can't return until all bits
1134 	 * are zero.
1135 	 */
1136 	for (;;) {
1137 		int toolong;
1138 
1139 		/*
1140 		 * Also execute any pending full invalidation request in
1141 		 * this loop.
1142 		 */
1143 		if (CPUMASK_TESTBIT(smp_invltlb_mask, md->mi.gd_cpuid)) {
1144 			ATOMIC_CPUMASK_NANDBIT(smp_invltlb_mask,
1145 					       md->mi.gd_cpuid);
1146 			cpu_invltlb();
1147 			cpu_mfence();
1148 		}
1149 
1150 #ifdef LOOPRECOVER
1151 		if (tsc_frequency && rdtsc() - tsc_base > tsc_frequency) {
1152 			kprintf("smp_inval_intr %d inv=%08jx tlbm=%08jx "
1153 				"idle=%08jx/%08jx\n",
1154 				md->mi.gd_cpuid,
1155 				smp_invmask.ary[0],
1156 				smp_invltlb_mask.ary[0],
1157 				smp_idleinvl_mask.ary[0],
1158 				smp_idleinvl_reqs.ary[0]);
1159 			tsc_base = rdtsc();
1160 			toolong = 1;
1161 		} else {
1162 			toolong = 0;
1163 		}
1164 #else
1165 		toolong = 0;
1166 #endif
1167 
1168 		/*
1169 		 * We can only add bits to the cpumask to test during the
1170 		 * loop because the smp_invmask bit is cleared once the
1171 		 * originator completes the command (the targets may still
1172 		 * be cycling their own completions in this loop, afterwords).
1173 		 *
1174 		 * lfence required prior to all tests as this Xinvltlb
1175 		 * interrupt could race the originator (already be in progress
1176 		 * wnen the originator decides to issue, due to an issue by
1177 		 * another cpu).
1178 		 */
1179 		cpu_lfence();
1180 		CPUMASK_ORMASK(cpumask, smp_invmask);
1181 		/*cpumask = smp_active_mask;*/	/* XXX */
1182 
1183 		if (pmap_inval_intr(&cpumask, toolong) == 0) {
1184 			/*
1185 			 * Clear our smurf mask to allow new IPIs, but deal
1186 			 * with potential races.
1187 			 */
1188 			break;
1189 		}
1190 
1191 		/*
1192 		 * Test if someone sent us another invalidation IPI, break
1193 		 * out so we can take it to avoid deadlocking the lapic
1194 		 * interrupt queue (? stupid intel, amd).
1195 		 */
1196 		if (md->gd_xinvaltlb == 2)
1197 			break;
1198 		/*
1199 		if (CPUMASK_TESTBIT(smp_smurf_mask, md->mi.gd_cpuid))
1200 			break;
1201 		*/
1202 	}
1203 
1204 	/*
1205 	 * Full invalidation request
1206 	 */
1207 	if (CPUMASK_TESTBIT(smp_invltlb_mask, md->mi.gd_cpuid)) {
1208 		ATOMIC_CPUMASK_NANDBIT(smp_invltlb_mask,
1209 				       md->mi.gd_cpuid);
1210 		cpu_invltlb();
1211 		cpu_mfence();
1212 	}
1213 
1214 #ifdef LOOPMASK_IN
1215 	ATOMIC_CPUMASK_NANDBIT(smp_in_mask, md->mi.gd_cpuid);
1216 #endif
1217 	/*
1218 	 * Check to see if another Xinvltlb interrupt occurred and loop up
1219 	 * if it did.
1220 	 */
1221 	cpu_disable_intr();
1222 	if (md->gd_xinvaltlb == 2) {
1223 		md->gd_xinvaltlb = 1;
1224 		goto loop;
1225 	}
1226 	md->gd_xinvaltlb = 0;
1227 }
1228 
1229 void
1230 cpu_wbinvd_on_all_cpus_callback(void *arg)
1231 {
1232 	wbinvd();
1233 }
1234 
1235 /*
1236  * When called the executing CPU will send an IPI to all other CPUs
1237  *  requesting that they halt execution.
1238  *
1239  * Usually (but not necessarily) called with 'other_cpus' as its arg.
1240  *
1241  *  - Signals all CPUs in map to stop.
1242  *  - Waits for each to stop.
1243  *
1244  * Returns:
1245  *  -1: error
1246  *   0: NA
1247  *   1: ok
1248  *
1249  * XXX FIXME: this is not MP-safe, needs a lock to prevent multiple CPUs
1250  *            from executing at same time.
1251  */
1252 int
1253 stop_cpus(cpumask_t map)
1254 {
1255 	cpumask_t mask;
1256 
1257 	CPUMASK_ANDMASK(map, smp_active_mask);
1258 
1259 	/* send the Xcpustop IPI to all CPUs in map */
1260 	selected_apic_ipi(map, XCPUSTOP_OFFSET, APIC_DELMODE_FIXED);
1261 
1262 	do {
1263 		mask = stopped_cpus;
1264 		CPUMASK_ANDMASK(mask, map);
1265 		/* spin */
1266 	} while (CPUMASK_CMPMASKNEQ(mask, map));
1267 
1268 	return 1;
1269 }
1270 
1271 
1272 /*
1273  * Called by a CPU to restart stopped CPUs.
1274  *
1275  * Usually (but not necessarily) called with 'stopped_cpus' as its arg.
1276  *
1277  *  - Signals all CPUs in map to restart.
1278  *  - Waits for each to restart.
1279  *
1280  * Returns:
1281  *  -1: error
1282  *   0: NA
1283  *   1: ok
1284  */
1285 int
1286 restart_cpus(cpumask_t map)
1287 {
1288 	cpumask_t mask;
1289 
1290 	/* signal other cpus to restart */
1291 	mask = map;
1292 	CPUMASK_ANDMASK(mask, smp_active_mask);
1293 	cpu_ccfence();
1294 	started_cpus = mask;
1295 	cpu_ccfence();
1296 
1297 	/* wait for each to clear its bit */
1298 	while (CPUMASK_CMPMASKNEQ(stopped_cpus, map))
1299 		cpu_pause();
1300 
1301 	return 1;
1302 }
1303 
1304 /*
1305  * This is called once the mpboot code has gotten us properly relocated
1306  * and the MMU turned on, etc.   ap_init() is actually the idle thread,
1307  * and when it returns the scheduler will call the real cpu_idle() main
1308  * loop for the idlethread.  Interrupts are disabled on entry and should
1309  * remain disabled at return.
1310  */
1311 void
1312 ap_init(void)
1313 {
1314 	int	cpu_id;
1315 
1316 	/*
1317 	 * Adjust smp_startup_mask to signal the BSP that we have started
1318 	 * up successfully.  Note that we do not yet hold the BGL.  The BSP
1319 	 * is waiting for our signal.
1320 	 *
1321 	 * We can't set our bit in smp_active_mask yet because we are holding
1322 	 * interrupts physically disabled and remote cpus could deadlock
1323 	 * trying to send us an IPI.
1324 	 */
1325 	ATOMIC_CPUMASK_ORBIT(smp_startup_mask, mycpu->gd_cpuid);
1326 	cpu_mfence();
1327 
1328 	/*
1329 	 * Interlock for LAPIC initialization.  Wait until mp_finish_lapic is
1330 	 * non-zero, then get the MP lock.
1331 	 *
1332 	 * Note: We are in a critical section.
1333 	 *
1334 	 * Note: we are the idle thread, we can only spin.
1335 	 *
1336 	 * Note: The load fence is memory volatile and prevents the compiler
1337 	 * from improperly caching mp_finish_lapic, and the cpu from improperly
1338 	 * caching it.
1339 	 */
1340 	while (mp_finish_lapic == 0) {
1341 		cpu_pause();
1342 		cpu_lfence();
1343 	}
1344 #if 0
1345 	while (try_mplock() == 0) {
1346 		cpu_pause();
1347 		cpu_lfence();
1348 	}
1349 #endif
1350 
1351 	if (cpu_feature & CPUID_TSC) {
1352 		/*
1353 		 * The BSP is constantly updating tsc0_offset, figure out
1354 		 * the relative difference to synchronize ktrdump.
1355 		 */
1356 		tsc_offsets[mycpu->gd_cpuid] = rdtsc() - tsc0_offset;
1357 	}
1358 
1359 	/* BSP may have changed PTD while we're waiting for the lock */
1360 	cpu_invltlb();
1361 
1362 	/* Build our map of 'other' CPUs. */
1363 	mycpu->gd_other_cpus = smp_startup_mask;
1364 	ATOMIC_CPUMASK_NANDBIT(mycpu->gd_other_cpus, mycpu->gd_cpuid);
1365 
1366 	/* A quick check from sanity claus */
1367 	cpu_id = APICID_TO_CPUID((lapic->id & 0xff000000) >> 24);
1368 	if (mycpu->gd_cpuid != cpu_id) {
1369 		kprintf("SMP: assigned cpuid = %d\n", mycpu->gd_cpuid);
1370 		kprintf("SMP: actual cpuid = %d lapicid %d\n",
1371 			cpu_id, (lapic->id & 0xff000000) >> 24);
1372 #if 0 /* JGXXX */
1373 		kprintf("PTD[MPPTDI] = %p\n", (void *)PTD[MPPTDI]);
1374 #endif
1375 		panic("cpuid mismatch! boom!!");
1376 	}
1377 
1378 	/* Initialize AP's local APIC for irq's */
1379 	lapic_init(FALSE);
1380 
1381 	/* LAPIC initialization is done */
1382 	ATOMIC_CPUMASK_ORBIT(smp_lapic_mask, mycpu->gd_cpuid);
1383 	cpu_mfence();
1384 
1385 #if 0
1386 	/* Let BSP move onto the next initialization stage */
1387 	rel_mplock();
1388 #endif
1389 
1390 	/*
1391 	 * Interlock for finalization.  Wait until mp_finish is non-zero,
1392 	 * then get the MP lock.
1393 	 *
1394 	 * Note: We are in a critical section.
1395 	 *
1396 	 * Note: we are the idle thread, we can only spin.
1397 	 *
1398 	 * Note: The load fence is memory volatile and prevents the compiler
1399 	 * from improperly caching mp_finish, and the cpu from improperly
1400 	 * caching it.
1401 	 */
1402 	while (mp_finish == 0) {
1403 		cpu_pause();
1404 		cpu_lfence();
1405 	}
1406 
1407 	/* BSP may have changed PTD while we're waiting for the lock */
1408 	cpu_invltlb();
1409 
1410 	/* Set memory range attributes for this CPU to match the BSP */
1411 	mem_range_AP_init();
1412 
1413 	/*
1414 	 * Once we go active we must process any IPIQ messages that may
1415 	 * have been queued, because no actual IPI will occur until we
1416 	 * set our bit in the smp_active_mask.  If we don't the IPI
1417 	 * message interlock could be left set which would also prevent
1418 	 * further IPIs.
1419 	 *
1420 	 * The idle loop doesn't expect the BGL to be held and while
1421 	 * lwkt_switch() normally cleans things up this is a special case
1422 	 * because we returning almost directly into the idle loop.
1423 	 *
1424 	 * The idle thread is never placed on the runq, make sure
1425 	 * nothing we've done put it there.
1426 	 */
1427 
1428 	/*
1429 	 * Hold a critical section and allow real interrupts to occur.  Zero
1430 	 * any spurious interrupts which have accumulated, then set our
1431 	 * smp_active_mask indicating that we are fully operational.
1432 	 */
1433 	crit_enter();
1434 	__asm __volatile("sti; pause; pause"::);
1435 	bzero(mdcpu->gd_ipending, sizeof(mdcpu->gd_ipending));
1436 	ATOMIC_CPUMASK_ORBIT(smp_active_mask, mycpu->gd_cpuid);
1437 
1438 	/*
1439 	 * Wait until all cpus have set their smp_active_mask and have fully
1440 	 * operational interrupts before proceeding.
1441 	 *
1442 	 * We need a final cpu_invltlb() because we would not have received
1443 	 * any until we set our bit in smp_active_mask.
1444 	 */
1445 	while (mp_finish == 1) {
1446 		cpu_pause();
1447 		cpu_lfence();
1448 	}
1449 	cpu_invltlb();
1450 
1451 	/*
1452 	 * Initialize per-cpu clocks and do other per-cpu initialization.
1453 	 * At this point code is expected to be able to use the full kernel
1454 	 * API.
1455 	 */
1456 	initclocks_pcpu();	/* clock interrupts (via IPIs) */
1457 
1458 	/*
1459 	 * Since we may have cleaned up the interrupt triggers, manually
1460 	 * process any pending IPIs before exiting our critical section.
1461 	 * Once the critical section has exited, normal interrupt processing
1462 	 * may occur.
1463 	 */
1464 	atomic_swap_int(&mycpu->gd_npoll, 0);
1465 	lwkt_process_ipiq();
1466 	crit_exit();
1467 
1468 	/*
1469 	 * Final final, allow the waiting BSP to resume the boot process,
1470 	 * return 'into' the idle thread bootstrap.
1471 	 */
1472 	ATOMIC_CPUMASK_ORBIT(smp_finalize_mask, mycpu->gd_cpuid);
1473 	KKASSERT((curthread->td_flags & TDF_RUNQ) == 0);
1474 }
1475 
1476 /*
1477  * Get SMP fully working before we start initializing devices.
1478  */
1479 static
1480 void
1481 ap_finish(void)
1482 {
1483 	if (bootverbose)
1484 		kprintf("Finish MP startup\n");
1485 	rel_mplock();
1486 
1487 	/*
1488 	 * Wait for the active mask to complete, after which all cpus will
1489 	 * be accepting interrupts.
1490 	 */
1491 	mp_finish = 1;
1492 	while (CPUMASK_CMPMASKNEQ(smp_active_mask, smp_startup_mask)) {
1493 		cpu_pause();
1494 		cpu_lfence();
1495 	}
1496 
1497 	/*
1498 	 * Wait for the finalization mask to complete, after which all cpus
1499 	 * have completely finished initializing and are entering or are in
1500 	 * their idle thread.
1501 	 *
1502 	 * BSP should have received all required invltlbs but do another
1503 	 * one just in case.
1504 	 */
1505 	cpu_invltlb();
1506 	mp_finish = 2;
1507 	while (CPUMASK_CMPMASKNEQ(smp_finalize_mask, smp_startup_mask)) {
1508 		cpu_pause();
1509 		cpu_lfence();
1510 	}
1511 
1512 	while (try_mplock() == 0) {
1513 		cpu_pause();
1514 		cpu_lfence();
1515 	}
1516 
1517 	if (bootverbose) {
1518 		kprintf("Active CPU Mask: %016jx\n",
1519 			(uintmax_t)CPUMASK_LOWMASK(smp_active_mask));
1520 	}
1521 }
1522 
1523 SYSINIT(finishsmp, SI_BOOT2_FINISH_SMP, SI_ORDER_FIRST, ap_finish, NULL);
1524 
1525 void
1526 cpu_send_ipiq(int dcpu)
1527 {
1528 	if (CPUMASK_TESTBIT(smp_active_mask, dcpu))
1529                 single_apic_ipi(dcpu, XIPIQ_OFFSET, APIC_DELMODE_FIXED);
1530 }
1531 
1532 #if 0	/* single_apic_ipi_passive() not working yet */
1533 /*
1534  * Returns 0 on failure, 1 on success
1535  */
1536 int
1537 cpu_send_ipiq_passive(int dcpu)
1538 {
1539         int r = 0;
1540 	if (CPUMASK_TESTBIT(smp_active_mask, dcpu)) {
1541                 r = single_apic_ipi_passive(dcpu, XIPIQ_OFFSET,
1542                                         APIC_DELMODE_FIXED);
1543         }
1544 	return(r);
1545 }
1546 #endif
1547 
1548 static void
1549 mp_bsp_simple_setup(void)
1550 {
1551 	struct mdglobaldata *gd;
1552 	size_t ipiq_size;
1553 
1554 	/* build our map of 'other' CPUs */
1555 	mycpu->gd_other_cpus = smp_startup_mask;
1556 	CPUMASK_NANDBIT(mycpu->gd_other_cpus, mycpu->gd_cpuid);
1557 
1558 	gd = (struct mdglobaldata *)mycpu;
1559 	gd->gd_acpi_id = CPUID_TO_ACPIID(mycpu->gd_cpuid);
1560 
1561 	ipiq_size = sizeof(struct lwkt_ipiq) * ncpus;
1562 	mycpu->gd_ipiq = (void *)kmem_alloc(&kernel_map, ipiq_size,
1563 					    VM_SUBSYS_IPIQ);
1564 	bzero(mycpu->gd_ipiq, ipiq_size);
1565 
1566 	pmap_set_opt();
1567 
1568 	if (cpu_feature & CPUID_TSC)
1569 		tsc0_offset = rdtsc();
1570 }
1571 
1572 
1573 /*
1574  * CPU TOPOLOGY DETECTION FUNCTIONS
1575  */
1576 
1577 /* Detect intel topology using CPUID
1578  * Ref: http://www.intel.com/Assets/PDF/appnote/241618.pdf, pg 41
1579  */
1580 static void
1581 detect_intel_topology(int count_htt_cores)
1582 {
1583 	int shift = 0;
1584 	int ecx_index = 0;
1585 	int core_plus_logical_bits = 0;
1586 	int cores_per_package;
1587 	int logical_per_package;
1588 	int logical_per_core;
1589 	unsigned int p[4];
1590 
1591 	if (cpu_high >= 0xb) {
1592 		goto FUNC_B;
1593 
1594 	} else if (cpu_high >= 0x4) {
1595 		goto FUNC_4;
1596 
1597 	} else {
1598 		core_bits = 0;
1599 		for (shift = 0; (1 << shift) < count_htt_cores; ++shift)
1600 			;
1601 		logical_CPU_bits = 1 << shift;
1602 		return;
1603 	}
1604 
1605 FUNC_B:
1606 	cpuid_count(0xb, FUNC_B_THREAD_LEVEL, p);
1607 
1608 	/* if 0xb not supported - fallback to 0x4 */
1609 	if (p[1] == 0 || (FUNC_B_TYPE(p[2]) != FUNC_B_THREAD_TYPE)) {
1610 		goto FUNC_4;
1611 	}
1612 
1613 	logical_CPU_bits = FUNC_B_BITS_SHIFT_NEXT_LEVEL(p[0]);
1614 
1615 	ecx_index = FUNC_B_THREAD_LEVEL + 1;
1616 	do {
1617 		cpuid_count(0xb, ecx_index, p);
1618 
1619 		/* Check for the Core type in the implemented sub leaves. */
1620 		if (FUNC_B_TYPE(p[2]) == FUNC_B_CORE_TYPE) {
1621 			core_plus_logical_bits = FUNC_B_BITS_SHIFT_NEXT_LEVEL(p[0]);
1622 			break;
1623 		}
1624 
1625 		ecx_index++;
1626 
1627 	} while (FUNC_B_TYPE(p[2]) != FUNC_B_INVALID_TYPE);
1628 
1629 	core_bits = core_plus_logical_bits - logical_CPU_bits;
1630 
1631 	return;
1632 
1633 FUNC_4:
1634 	cpuid_count(0x4, 0, p);
1635 	cores_per_package = FUNC_4_MAX_CORE_NO(p[0]) + 1;
1636 
1637 	logical_per_package = count_htt_cores;
1638 	logical_per_core = logical_per_package / cores_per_package;
1639 
1640 	for (shift = 0; (1 << shift) < logical_per_core; ++shift)
1641 		;
1642 	logical_CPU_bits = shift;
1643 
1644 	for (shift = 0; (1 << shift) < cores_per_package; ++shift)
1645 		;
1646 	core_bits = shift;
1647 
1648 	return;
1649 }
1650 
1651 /* Detect AMD topology using CPUID
1652  * Ref: http://support.amd.com/us/Embedded_TechDocs/25481.pdf, last page
1653  */
1654 static void
1655 detect_amd_topology(int count_htt_cores)
1656 {
1657 	int shift = 0;
1658 	if ((cpu_feature & CPUID_HTT)
1659 			&& (amd_feature2 & AMDID2_CMP)) {
1660 
1661 		if (cpu_procinfo2 & AMDID_COREID_SIZE) {
1662 			core_bits = (cpu_procinfo2 & AMDID_COREID_SIZE)
1663 			    >> AMDID_COREID_SIZE_SHIFT;
1664 		} else {
1665 			core_bits = (cpu_procinfo2 & AMDID_CMP_CORES) + 1;
1666 			for (shift = 0; (1 << shift) < core_bits; ++shift)
1667 				;
1668 			core_bits = shift;
1669 		}
1670 
1671 		logical_CPU_bits = count_htt_cores >> core_bits;
1672 		for (shift = 0; (1 << shift) < logical_CPU_bits; ++shift)
1673 			;
1674 		logical_CPU_bits = shift;
1675 	} else {
1676 		for (shift = 0; (1 << shift) < count_htt_cores; ++shift)
1677 			;
1678 		core_bits = shift;
1679 		logical_CPU_bits = 0;
1680 	}
1681 }
1682 
1683 static void
1684 amd_get_compute_unit_id(void *arg)
1685 {
1686 	u_int regs[4];
1687 
1688 	do_cpuid(0x8000001e, regs);
1689 	cpu_node_t * mynode = get_cpu_node_by_cpuid(mycpuid);
1690 	/*
1691 	 * AMD - CPUID Specification September 2010
1692 	 * page 34 - //ComputeUnitID = ebx[0:7]//
1693 	 */
1694 	mynode->compute_unit_id = regs[1] & 0xff;
1695 }
1696 
1697 int
1698 fix_amd_topology(void)
1699 {
1700 	cpumask_t mask;
1701 
1702 	if (cpu_vendor_id != CPU_VENDOR_AMD)
1703 		return -1;
1704 	if ((amd_feature2 & AMDID2_TOPOEXT) == 0)
1705 		return -1;
1706 
1707 	CPUMASK_ASSALLONES(mask);
1708 	lwkt_cpusync_simple(mask, amd_get_compute_unit_id, NULL);
1709 
1710 	kprintf("Compute unit iDS:\n");
1711 	int i;
1712 	for (i = 0; i < ncpus; i++) {
1713 		kprintf("%d-%d; \n",
1714 			i, get_cpu_node_by_cpuid(i)->compute_unit_id);
1715 	}
1716 
1717 	return 0;
1718 }
1719 
1720 /* Calculate
1721  * - logical_CPU_bits
1722  * - core_bits
1723  * With the values above (for AMD or INTEL) we are able to generally
1724  * detect the CPU topology (number of cores for each level):
1725  * Ref: http://wiki.osdev.org/Detecting_CPU_Topology_(80x86)
1726  * Ref: http://www.multicoreinfo.com/research/papers/whitepapers/Intel-detect-topology.pdf
1727  */
1728 void
1729 detect_cpu_topology(void)
1730 {
1731 	static int topology_detected = 0;
1732 	int count = 0;
1733 
1734 	if (topology_detected)
1735 		goto OUT;
1736 	if ((cpu_feature & CPUID_HTT) == 0) {
1737 		core_bits = 0;
1738 		logical_CPU_bits = 0;
1739 		goto OUT;
1740 	}
1741 	count = (cpu_procinfo & CPUID_HTT_CORES) >> CPUID_HTT_CORE_SHIFT;
1742 
1743 	if (cpu_vendor_id == CPU_VENDOR_INTEL)
1744 		detect_intel_topology(count);
1745 	else if (cpu_vendor_id == CPU_VENDOR_AMD)
1746 		detect_amd_topology(count);
1747 	topology_detected = 1;
1748 
1749 OUT:
1750 	if (bootverbose)
1751 		kprintf("Bits within APICID: logical_CPU_bits: %d; core_bits: %d\n",
1752 		    logical_CPU_bits, core_bits);
1753 }
1754 
1755 /* Interface functions to calculate chip_ID,
1756  * core_number and logical_number
1757  * Ref: http://wiki.osdev.org/Detecting_CPU_Topology_(80x86)
1758  */
1759 int
1760 get_chip_ID(int cpuid)
1761 {
1762 	return get_apicid_from_cpuid(cpuid) >>
1763 	    (logical_CPU_bits + core_bits);
1764 }
1765 
1766 int
1767 get_core_number_within_chip(int cpuid)
1768 {
1769 	return (get_apicid_from_cpuid(cpuid) >> logical_CPU_bits) &
1770 	    ( (1 << core_bits) -1);
1771 }
1772 
1773 int
1774 get_logical_CPU_number_within_core(int cpuid)
1775 {
1776 	return get_apicid_from_cpuid(cpuid) &
1777 	    ( (1 << logical_CPU_bits) -1);
1778 }
1779