xref: /freebsd/sys/x86/x86/local_apic.c (revision 12cce5994b92f8235f379d660ccb28da8e69f55b)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1996, by Steve Passe
5  * All rights reserved.
6  * Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. The name of the developer may NOT be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  * 3. Neither the name of the author nor the names of any co-contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Local APIC support on Pentium and later processors.
34  */
35 
36 #include <sys/cdefs.h>
37 #include "opt_atpic.h"
38 #include "opt_hwpmc_hooks.h"
39 
40 #include "opt_ddb.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/asan.h>
45 #include <sys/bus.h>
46 #include <sys/kernel.h>
47 #include <sys/lock.h>
48 #include <sys/malloc.h>
49 #include <sys/msan.h>
50 #include <sys/mutex.h>
51 #include <sys/pcpu.h>
52 #include <sys/proc.h>
53 #include <sys/sched.h>
54 #include <sys/smp.h>
55 #include <sys/sysctl.h>
56 #include <sys/timeet.h>
57 #include <sys/timetc.h>
58 
59 #include <vm/vm.h>
60 #include <vm/pmap.h>
61 
62 #include <x86/apicreg.h>
63 #include <machine/clock.h>
64 #include <machine/cpufunc.h>
65 #include <machine/cputypes.h>
66 #include <machine/fpu.h>
67 #include <machine/frame.h>
68 #include <machine/intr_machdep.h>
69 #include <x86/apicvar.h>
70 #include <x86/mca.h>
71 #include <machine/md_var.h>
72 #include <machine/smp.h>
73 #include <machine/specialreg.h>
74 #include <x86/init.h>
75 
76 #ifdef DDB
77 #include <sys/interrupt.h>
78 #include <ddb/ddb.h>
79 #endif
80 
81 #ifdef __amd64__
82 #define	SDT_APIC	SDT_SYSIGT
83 #define	GSEL_APIC	0
84 #else
85 #define	SDT_APIC	SDT_SYS386IGT
86 #define	GSEL_APIC	GSEL(GCODE_SEL, SEL_KPL)
87 #endif
88 
89 static MALLOC_DEFINE(M_LAPIC, "local_apic", "Local APIC items");
90 
91 /* Sanity checks on IDT vectors. */
92 CTASSERT(APIC_IO_INTS + APIC_NUM_IOINTS == APIC_TIMER_INT);
93 CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS);
94 CTASSERT(APIC_LOCAL_INTS == 240);
95 CTASSERT(IPI_STOP < APIC_SPURIOUS_INT);
96 
97 /*
98  * I/O interrupts use non-negative IRQ values.  These values are used
99  * to mark unused IDT entries or IDT entries reserved for a non-I/O
100  * interrupt.
101  */
102 #define	IRQ_FREE	-1
103 #define	IRQ_TIMER	-2
104 #define	IRQ_SYSCALL	-3
105 #define	IRQ_DTRACE_RET	-4
106 #define	IRQ_EVTCHN	-5
107 
108 enum lat_timer_mode {
109 	LAT_MODE_UNDEF =	0,
110 	LAT_MODE_PERIODIC =	1,
111 	LAT_MODE_ONESHOT =	2,
112 	LAT_MODE_DEADLINE =	3,
113 };
114 
115 /*
116  * Support for local APICs.  Local APICs manage interrupts on each
117  * individual processor as opposed to I/O APICs which receive interrupts
118  * from I/O devices and then forward them on to the local APICs.
119  *
120  * Local APICs can also send interrupts to each other thus providing the
121  * mechanism for IPIs.
122  */
123 
124 struct lvt {
125 	u_int lvt_edgetrigger:1;
126 	u_int lvt_activehi:1;
127 	u_int lvt_masked:1;
128 	u_int lvt_active:1;
129 	u_int lvt_mode:16;
130 	u_int lvt_vector:8;
131 };
132 
133 struct lapic {
134 	struct lvt la_lvts[APIC_LVT_MAX + 1];
135 	struct lvt la_elvts[APIC_ELVT_MAX + 1];
136 	u_int la_id:8;
137 	u_int la_cluster:4;
138 	u_int la_cluster_id:2;
139 	u_int la_present:1;
140 	u_long *la_timer_count;
141 	uint64_t la_timer_period;
142 	enum lat_timer_mode la_timer_mode;
143 	uint32_t lvt_timer_base;
144 	uint32_t lvt_timer_last;
145 	/* Include IDT_SYSCALL to make indexing easier. */
146 	int la_ioint_irqs[APIC_NUM_IOINTS + 1];
147 } static *lapics;
148 
149 /* Global defaults for local APIC LVT entries. */
150 static struct lvt lvts[APIC_LVT_MAX + 1] = {
151 	{ 1, 1, 1, 1, APIC_LVT_DM_EXTINT, 0 },	/* LINT0: masked ExtINT */
152 	{ 1, 1, 0, 1, APIC_LVT_DM_NMI, 0 },	/* LINT1: NMI */
153 	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_TIMER_INT },	/* Timer */
154 	{ 1, 1, 0, 1, APIC_LVT_DM_FIXED, APIC_ERROR_INT },	/* Error */
155 	{ 1, 1, 1, 1, APIC_LVT_DM_NMI, 0 },	/* PMC */
156 	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_THERMAL_INT },	/* Thermal */
157 	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_CMC_INT },	/* CMCI */
158 };
159 
160 /* Global defaults for AMD local APIC ELVT entries. */
161 static struct lvt elvts[APIC_ELVT_MAX + 1] = {
162 	{ 1, 1, 1, 0, APIC_LVT_DM_FIXED, 0 },
163 	{ 1, 1, 1, 0, APIC_LVT_DM_FIXED, APIC_CMC_INT },
164 	{ 1, 1, 1, 0, APIC_LVT_DM_FIXED, 0 },
165 	{ 1, 1, 1, 0, APIC_LVT_DM_FIXED, 0 },
166 };
167 
168 static inthand_t *ioint_handlers[] = {
169 	NULL,			/* 0 - 31 */
170 	IDTVEC(apic_isr1),	/* 32 - 63 */
171 	IDTVEC(apic_isr2),	/* 64 - 95 */
172 	IDTVEC(apic_isr3),	/* 96 - 127 */
173 	IDTVEC(apic_isr4),	/* 128 - 159 */
174 	IDTVEC(apic_isr5),	/* 160 - 191 */
175 	IDTVEC(apic_isr6),	/* 192 - 223 */
176 	IDTVEC(apic_isr7),	/* 224 - 255 */
177 };
178 
179 static inthand_t *ioint_pti_handlers[] = {
180 	NULL,			/* 0 - 31 */
181 	IDTVEC(apic_isr1_pti),	/* 32 - 63 */
182 	IDTVEC(apic_isr2_pti),	/* 64 - 95 */
183 	IDTVEC(apic_isr3_pti),	/* 96 - 127 */
184 	IDTVEC(apic_isr4_pti),	/* 128 - 159 */
185 	IDTVEC(apic_isr5_pti),	/* 160 - 191 */
186 	IDTVEC(apic_isr6_pti),	/* 192 - 223 */
187 	IDTVEC(apic_isr7_pti),	/* 224 - 255 */
188 };
189 
190 static u_int32_t lapic_timer_divisors[] = {
191 	APIC_TDCR_1, APIC_TDCR_2, APIC_TDCR_4, APIC_TDCR_8, APIC_TDCR_16,
192 	APIC_TDCR_32, APIC_TDCR_64, APIC_TDCR_128
193 };
194 
195 extern inthand_t IDTVEC(rsvd_pti), IDTVEC(rsvd);
196 
197 volatile char *lapic_map;
198 vm_paddr_t lapic_paddr = DEFAULT_APIC_BASE;
199 int x2apic_mode;
200 int lapic_eoi_suppression;
201 static int lapic_timer_tsc_deadline;
202 static u_long lapic_timer_divisor, count_freq;
203 static struct eventtimer lapic_et;
204 #ifdef SMP
205 static uint64_t lapic_ipi_wait_mult;
206 static int __read_mostly lapic_ds_idle_timeout = 1000000;
207 #endif
208 unsigned int max_apic_id;
209 
210 SYSCTL_NODE(_hw, OID_AUTO, apic, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
211     "APIC options");
212 SYSCTL_INT(_hw_apic, OID_AUTO, x2apic_mode, CTLFLAG_RD, &x2apic_mode, 0, "");
213 SYSCTL_INT(_hw_apic, OID_AUTO, eoi_suppression, CTLFLAG_RD,
214     &lapic_eoi_suppression, 0, "");
215 SYSCTL_INT(_hw_apic, OID_AUTO, timer_tsc_deadline, CTLFLAG_RD,
216     &lapic_timer_tsc_deadline, 0, "");
217 #ifdef SMP
218 SYSCTL_INT(_hw_apic, OID_AUTO, ds_idle_timeout, CTLFLAG_RWTUN,
219     &lapic_ds_idle_timeout, 0,
220     "timeout (in us) for APIC Delivery Status to become Idle (xAPIC only)");
221 #endif
222 
223 static void lapic_calibrate_initcount(struct lapic *la);
224 
225 /*
226  * Use __nosanitizethread to exempt the LAPIC I/O accessors from KCSan
227  * instrumentation.  Otherwise, if x2APIC is not available, use of the global
228  * lapic_map will generate a KCSan false positive.  While the mapping is
229  * shared among all CPUs, the physical access will always take place on the
230  * local CPU's APIC, so there isn't in fact a race here.  Furthermore, the
231  * KCSan warning printf can cause a panic if issued during LAPIC access,
232  * due to attempted recursive use of event timer resources.
233  */
234 
235 static uint32_t __nosanitizethread
lapic_read32(enum LAPIC_REGISTERS reg)236 lapic_read32(enum LAPIC_REGISTERS reg)
237 {
238 	uint32_t res;
239 
240 	if (x2apic_mode) {
241 		res = rdmsr32(MSR_APIC_000 + reg);
242 	} else {
243 		res = *(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL);
244 	}
245 	return (res);
246 }
247 
248 static void __nosanitizethread
lapic_write32(enum LAPIC_REGISTERS reg,uint32_t val)249 lapic_write32(enum LAPIC_REGISTERS reg, uint32_t val)
250 {
251 
252 	if (x2apic_mode) {
253 		mfence();
254 		lfence();
255 		wrmsr(MSR_APIC_000 + reg, val);
256 	} else {
257 		*(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL) = val;
258 	}
259 }
260 
261 static void __nosanitizethread
lapic_write32_nofence(enum LAPIC_REGISTERS reg,uint32_t val)262 lapic_write32_nofence(enum LAPIC_REGISTERS reg, uint32_t val)
263 {
264 
265 	if (x2apic_mode) {
266 		wrmsr(MSR_APIC_000 + reg, val);
267 	} else {
268 		*(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL) = val;
269 	}
270 }
271 
272 #ifdef SMP
273 static uint64_t
lapic_read_icr_lo(void)274 lapic_read_icr_lo(void)
275 {
276 
277 	return (lapic_read32(LAPIC_ICR_LO));
278 }
279 
280 static void
lapic_write_icr(uint32_t vhi,uint32_t vlo)281 lapic_write_icr(uint32_t vhi, uint32_t vlo)
282 {
283 	register_t saveintr;
284 	uint64_t v;
285 
286 	if (x2apic_mode) {
287 		v = ((uint64_t)vhi << 32) | vlo;
288 		mfence();
289 		wrmsr(MSR_APIC_000 + LAPIC_ICR_LO, v);
290 	} else {
291 		saveintr = intr_disable();
292 		lapic_write32(LAPIC_ICR_HI, vhi);
293 		lapic_write32(LAPIC_ICR_LO, vlo);
294 		intr_restore(saveintr);
295 	}
296 }
297 
298 static void
lapic_write_icr_lo(uint32_t vlo)299 lapic_write_icr_lo(uint32_t vlo)
300 {
301 
302 	if (x2apic_mode) {
303 		mfence();
304 		wrmsr(MSR_APIC_000 + LAPIC_ICR_LO, vlo);
305 	} else {
306 		lapic_write32(LAPIC_ICR_LO, vlo);
307 	}
308 }
309 
310 static void
lapic_write_self_ipi(uint32_t vector)311 lapic_write_self_ipi(uint32_t vector)
312 {
313 
314 	KASSERT(x2apic_mode, ("SELF IPI write in xAPIC mode"));
315 	wrmsr(MSR_APIC_000 + LAPIC_SELF_IPI, vector);
316 }
317 #endif /* SMP */
318 
319 static void
lapic_enable_x2apic(void)320 lapic_enable_x2apic(void)
321 {
322 	uint64_t apic_base;
323 
324 	apic_base = rdmsr(MSR_APICBASE);
325 	apic_base |= APICBASE_X2APIC | APICBASE_ENABLED;
326 	wrmsr(MSR_APICBASE, apic_base);
327 }
328 
329 bool
lapic_is_x2apic(void)330 lapic_is_x2apic(void)
331 {
332 	uint64_t apic_base;
333 
334 	apic_base = rdmsr(MSR_APICBASE);
335 	return ((apic_base & (APICBASE_X2APIC | APICBASE_ENABLED)) ==
336 	    (APICBASE_X2APIC | APICBASE_ENABLED));
337 }
338 
339 static void	lapic_enable(void);
340 static void	lapic_resume(struct pic *pic, bool suspend_cancelled);
341 static void	lapic_timer_oneshot(struct lapic *);
342 static void	lapic_timer_oneshot_nointr(struct lapic *, uint32_t);
343 static void	lapic_timer_periodic(struct lapic *);
344 static void	lapic_timer_deadline(struct lapic *);
345 static void	lapic_timer_stop(struct lapic *);
346 static void	lapic_timer_set_divisor(u_int divisor);
347 static uint32_t	lvt_mode(struct lapic *la, u_int pin, uint32_t value);
348 static int	lapic_et_start(struct eventtimer *et,
349 		    sbintime_t first, sbintime_t period);
350 static int	lapic_et_stop(struct eventtimer *et);
351 static u_int	apic_idt_to_irq(u_int apic_id, u_int vector);
352 static void	lapic_set_tpr(u_int vector);
353 
354 struct pic lapic_pic = { .pic_resume = lapic_resume };
355 
356 static uint32_t
lvt_mode_impl(struct lapic * la,struct lvt * lvt,u_int pin,uint32_t value)357 lvt_mode_impl(struct lapic *la, struct lvt *lvt, u_int pin, uint32_t value)
358 {
359 
360 	value &= ~(APIC_LVT_M | APIC_LVT_TM | APIC_LVT_IIPP | APIC_LVT_DM |
361 	    APIC_LVT_VECTOR);
362 	if (lvt->lvt_edgetrigger == 0)
363 		value |= APIC_LVT_TM;
364 	if (lvt->lvt_activehi == 0)
365 		value |= APIC_LVT_IIPP_INTALO;
366 	if (lvt->lvt_masked)
367 		value |= APIC_LVT_M;
368 	value |= lvt->lvt_mode;
369 	switch (lvt->lvt_mode) {
370 	case APIC_LVT_DM_NMI:
371 	case APIC_LVT_DM_SMI:
372 	case APIC_LVT_DM_INIT:
373 	case APIC_LVT_DM_EXTINT:
374 		if (!lvt->lvt_edgetrigger && bootverbose) {
375 			printf("lapic%u: Forcing LINT%u to edge trigger\n",
376 			    la->la_id, pin);
377 			value &= ~APIC_LVT_TM;
378 		}
379 		/* Use a vector of 0. */
380 		break;
381 	case APIC_LVT_DM_FIXED:
382 		value |= lvt->lvt_vector;
383 		break;
384 	default:
385 		panic("bad APIC LVT delivery mode: %#x\n", value);
386 	}
387 	return (value);
388 }
389 
390 static uint32_t
lvt_mode(struct lapic * la,u_int pin,uint32_t value)391 lvt_mode(struct lapic *la, u_int pin, uint32_t value)
392 {
393 	struct lvt *lvt;
394 
395 	KASSERT(pin <= APIC_LVT_MAX,
396 	    ("%s: pin %u out of range", __func__, pin));
397 	if (la->la_lvts[pin].lvt_active)
398 		lvt = &la->la_lvts[pin];
399 	else
400 		lvt = &lvts[pin];
401 
402 	return (lvt_mode_impl(la, lvt, pin, value));
403 }
404 
405 static uint32_t
elvt_mode(struct lapic * la,u_int idx,uint32_t value)406 elvt_mode(struct lapic *la, u_int idx, uint32_t value)
407 {
408 	struct lvt *elvt;
409 
410 	KASSERT(idx <= APIC_ELVT_MAX,
411 	    ("%s: idx %u out of range", __func__, idx));
412 
413 	elvt = &la->la_elvts[idx];
414 	KASSERT(elvt->lvt_active, ("%s: ELVT%u is not active", __func__, idx));
415 	KASSERT(elvt->lvt_edgetrigger,
416 	    ("%s: ELVT%u is not edge triggered", __func__, idx));
417 	KASSERT(elvt->lvt_activehi,
418 	    ("%s: ELVT%u is not active high", __func__, idx));
419 	return (lvt_mode_impl(la, elvt, idx, value));
420 }
421 
422 /*
423  * Map the local APIC and setup necessary interrupt vectors.
424  */
425 void
lapic_init(vm_paddr_t addr)426 lapic_init(vm_paddr_t addr)
427 {
428 #ifdef SMP
429 	uint64_t r, r1, r2, rx;
430 #endif
431 	uint32_t ver;
432 	int i;
433 	bool arat;
434 
435 	TSENTER();
436 
437 	/*
438 	 * Enable x2APIC mode if possible. Map the local APIC
439 	 * registers page.
440 	 *
441 	 * Keep the LAPIC registers page mapped uncached for x2APIC
442 	 * mode too, to have direct map page attribute set to
443 	 * uncached.  This is needed to work around CPU errata present
444 	 * on all Intel processors.
445 	 */
446 	KASSERT(trunc_page(addr) == addr,
447 	    ("local APIC not aligned on a page boundary"));
448 	lapic_paddr = addr;
449 	lapic_map = pmap_mapdev(addr, PAGE_SIZE);
450 	if (x2apic_mode) {
451 		lapic_enable_x2apic();
452 		lapic_map = NULL;
453 	}
454 
455 	/* Setup the spurious interrupt handler. */
456 	setidt(APIC_SPURIOUS_INT, IDTVEC(spuriousint), SDT_APIC, SEL_KPL,
457 	    GSEL_APIC);
458 
459 	/* Perform basic initialization of the BSP's local APIC. */
460 	lapic_enable();
461 
462 	/* Set BSP's per-CPU local APIC ID. */
463 	PCPU_SET(apic_id, lapic_id());
464 
465 	/* Local APIC timer interrupt. */
466 	setidt(APIC_TIMER_INT, pti ? IDTVEC(timerint_pti) : IDTVEC(timerint),
467 	    SDT_APIC, SEL_KPL, GSEL_APIC);
468 
469 	/* Local APIC error interrupt. */
470 	setidt(APIC_ERROR_INT, pti ? IDTVEC(errorint_pti) : IDTVEC(errorint),
471 	    SDT_APIC, SEL_KPL, GSEL_APIC);
472 
473 	/* XXX: Thermal interrupt */
474 
475 	/* Local APIC CMCI. */
476 	setidt(APIC_CMC_INT, pti ? IDTVEC(cmcint_pti) : IDTVEC(cmcint),
477 	    SDT_APIC, SEL_KPL, GSEL_APIC);
478 
479 	if ((resource_int_value("apic", 0, "clock", &i) != 0 || i != 0)) {
480 		/* Set if APIC timer runs in C3. */
481 		arat = (cpu_power_eax & CPUTPM1_ARAT);
482 
483 		bzero(&lapic_et, sizeof(lapic_et));
484 		lapic_et.et_name = "LAPIC";
485 		lapic_et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT |
486 		    ET_FLAGS_PERCPU;
487 		lapic_et.et_quality = 600;
488 		if (!arat) {
489 			lapic_et.et_flags |= ET_FLAGS_C3STOP;
490 			lapic_et.et_quality = 100;
491 		}
492 		if ((cpu_feature & CPUID_TSC) != 0 &&
493 		    (cpu_feature2 & CPUID2_TSCDLT) != 0 &&
494 		    tsc_is_invariant && tsc_freq != 0) {
495 			lapic_timer_tsc_deadline = 1;
496 			TUNABLE_INT_FETCH("hw.apic.timer_tsc_deadline",
497 			    &lapic_timer_tsc_deadline);
498 		}
499 
500 		lapic_et.et_frequency = 0;
501 		/* We don't know frequency yet, so trying to guess. */
502 		lapic_et.et_min_period = 0x00001000LL;
503 		lapic_et.et_max_period = SBT_1S;
504 		lapic_et.et_start = lapic_et_start;
505 		lapic_et.et_stop = lapic_et_stop;
506 		lapic_et.et_priv = NULL;
507 		et_register(&lapic_et);
508 	}
509 
510 	/*
511 	 * Set lapic_eoi_suppression after lapic_enable(), to not
512 	 * enable suppression in the hardware prematurely.  Note that
513 	 * we by default enable suppression even when system only has
514 	 * one IO-APIC, since EOI is broadcasted to all APIC agents,
515 	 * including CPUs, otherwise.
516 	 *
517 	 * It seems that at least some KVM versions report
518 	 * EOI_SUPPRESSION bit, but auto-EOI does not work.
519 	 */
520 	ver = lapic_read32(LAPIC_VERSION);
521 	if ((ver & APIC_VER_EOI_SUPPRESSION) != 0) {
522 		lapic_eoi_suppression = 1;
523 		if (vm_guest == VM_GUEST_KVM) {
524 			if (bootverbose)
525 				printf(
526 		       "KVM -- disabling lapic eoi suppression\n");
527 			lapic_eoi_suppression = 0;
528 		}
529 		TUNABLE_INT_FETCH("hw.apic.eoi_suppression",
530 		    &lapic_eoi_suppression);
531 	}
532 
533 #ifdef SMP
534 #define	LOOPS	1000
535 	/*
536 	 * Calibrate the busy loop waiting for IPI ack in xAPIC mode.
537 	 * lapic_ipi_wait_mult contains the number of iterations which
538 	 * approximately delay execution for 1 microsecond (the
539 	 * argument to lapic_ipi_wait() is in microseconds).
540 	 *
541 	 * We assume that TSC is present and already measured.
542 	 * Possible TSC frequency jumps are irrelevant to the
543 	 * calibration loop below, the CPU clock management code is
544 	 * not yet started, and we do not enter sleep states.
545 	 */
546 	KASSERT((cpu_feature & CPUID_TSC) != 0 && tsc_freq != 0,
547 	    ("TSC not initialized"));
548 	if (!x2apic_mode) {
549 		r = rdtsc();
550 		for (rx = 0; rx < LOOPS; rx++) {
551 			(void)lapic_read_icr_lo();
552 			ia32_pause();
553 		}
554 		r = rdtsc() - r;
555 		r1 = tsc_freq * LOOPS;
556 		r2 = r * 1000000;
557 		lapic_ipi_wait_mult = r1 >= r2 ? r1 / r2 : 1;
558 		if (bootverbose) {
559 			printf("LAPIC: ipi_wait() us multiplier %ju (r %ju "
560 			    "tsc %ju)\n", (uintmax_t)lapic_ipi_wait_mult,
561 			    (uintmax_t)r, (uintmax_t)tsc_freq);
562 		}
563 	}
564 #undef LOOPS
565 #endif /* SMP */
566 
567 	TSEXIT();
568 }
569 
570 /*
571  * Create a local APIC instance.
572  */
573 void
lapic_create(u_int apic_id,int boot_cpu)574 lapic_create(u_int apic_id, int boot_cpu)
575 {
576 	int i;
577 
578 	if (apic_id > max_apic_id) {
579 		printf("APIC: Ignoring local APIC with ID %d\n", apic_id);
580 		if (boot_cpu)
581 			panic("Can't ignore BSP");
582 		return;
583 	}
584 	KASSERT(!lapics[apic_id].la_present, ("duplicate local APIC %u",
585 	    apic_id));
586 
587 	/*
588 	 * Assume no local LVT overrides and a cluster of 0 and
589 	 * intra-cluster ID of 0.
590 	 */
591 	lapics[apic_id].la_present = 1;
592 	lapics[apic_id].la_id = apic_id;
593 	for (i = 0; i <= APIC_LVT_MAX; i++) {
594 		lapics[apic_id].la_lvts[i] = lvts[i];
595 		lapics[apic_id].la_lvts[i].lvt_active = 0;
596 	}
597 	for (i = 0; i <= APIC_ELVT_MAX; i++) {
598 		lapics[apic_id].la_elvts[i] = elvts[i];
599 		lapics[apic_id].la_elvts[i].lvt_active = 0;
600 	}
601 	for (i = 0; i <= APIC_NUM_IOINTS; i++)
602 	    lapics[apic_id].la_ioint_irqs[i] = IRQ_FREE;
603 	lapics[apic_id].la_ioint_irqs[IDT_SYSCALL - APIC_IO_INTS] = IRQ_SYSCALL;
604 	lapics[apic_id].la_ioint_irqs[APIC_TIMER_INT - APIC_IO_INTS] =
605 	    IRQ_TIMER;
606 #ifdef KDTRACE_HOOKS
607 	lapics[apic_id].la_ioint_irqs[IDT_DTRACE_RET - APIC_IO_INTS] =
608 	    IRQ_DTRACE_RET;
609 #endif
610 #ifdef XENHVM
611 	lapics[apic_id].la_ioint_irqs[IDT_EVTCHN - APIC_IO_INTS] = IRQ_EVTCHN;
612 #endif
613 
614 #ifdef SMP
615 	cpu_add(apic_id, boot_cpu);
616 #endif
617 }
618 
619 static inline uint32_t
amd_read_ext_features(void)620 amd_read_ext_features(void)
621 {
622 	uint32_t version;
623 
624 	if (cpu_vendor_id != CPU_VENDOR_AMD &&
625 	    cpu_vendor_id != CPU_VENDOR_HYGON)
626 		return (0);
627 	version = lapic_read32(LAPIC_VERSION);
628 	if ((version & APIC_VER_AMD_EXT_SPACE) != 0)
629 		return (lapic_read32(LAPIC_EXT_FEATURES));
630 	else
631 		return (0);
632 }
633 
634 static inline uint32_t
amd_read_elvt_count(void)635 amd_read_elvt_count(void)
636 {
637 	uint32_t extf;
638 	uint32_t count;
639 
640 	extf = amd_read_ext_features();
641 	count = (extf & APIC_EXTF_ELVT_MASK) >> APIC_EXTF_ELVT_SHIFT;
642 	count = min(count, APIC_ELVT_MAX + 1);
643 	return (count);
644 }
645 
646 /*
647  * Dump contents of local APIC registers
648  */
649 void
lapic_dump(const char * str)650 lapic_dump(const char* str)
651 {
652 	uint32_t version;
653 	uint32_t maxlvt;
654 	uint32_t extf;
655 	int elvt_count;
656 	int i;
657 
658 	version = lapic_read32(LAPIC_VERSION);
659 	maxlvt = (version & APIC_VER_MAXLVT) >> MAXLVTSHIFT;
660 	printf("cpu%d %s:\n", PCPU_GET(cpuid), str);
661 	printf("     ID: 0x%08x   VER: 0x%08x LDR: 0x%08x DFR: 0x%08x",
662 	    lapic_read32(LAPIC_ID), version,
663 	    lapic_read32(LAPIC_LDR), x2apic_mode ? 0 : lapic_read32(LAPIC_DFR));
664 	if ((cpu_feature2 & CPUID2_X2APIC) != 0)
665 		printf(" x2APIC: %d", x2apic_mode);
666 	printf("\n  lint0: 0x%08x lint1: 0x%08x TPR: 0x%08x SVR: 0x%08x\n",
667 	    lapic_read32(LAPIC_LVT_LINT0), lapic_read32(LAPIC_LVT_LINT1),
668 	    lapic_read32(LAPIC_TPR), lapic_read32(LAPIC_SVR));
669 	printf("  timer: 0x%08x therm: 0x%08x err: 0x%08x",
670 	    lapic_read32(LAPIC_LVT_TIMER), lapic_read32(LAPIC_LVT_THERMAL),
671 	    lapic_read32(LAPIC_LVT_ERROR));
672 	if (maxlvt >= APIC_LVT_PMC)
673 		printf(" pmc: 0x%08x", lapic_read32(LAPIC_LVT_PCINT));
674 	printf("\n");
675 	if (maxlvt >= APIC_LVT_CMCI)
676 		printf("   cmci: 0x%08x\n", lapic_read32(LAPIC_LVT_CMCI));
677 	extf = amd_read_ext_features();
678 	if (extf != 0) {
679 		printf("   AMD ext features: 0x%08x", extf);
680 		elvt_count = amd_read_elvt_count();
681 		for (i = 0; i < elvt_count; i++)
682 			printf("%s elvt%d: 0x%08x", (i % 4) ? "" : "\n ", i,
683 			    lapic_read32(LAPIC_EXT_LVT0 + i));
684 		printf("\n");
685 	}
686 }
687 
688 void
lapic_xapic_mode(void)689 lapic_xapic_mode(void)
690 {
691 	register_t saveintr;
692 
693 	saveintr = intr_disable();
694 	if (x2apic_mode)
695 		lapic_enable_x2apic();
696 	intr_restore(saveintr);
697 }
698 
699 void
lapic_setup(int boot)700 lapic_setup(int boot)
701 {
702 	struct lapic *la;
703 	uint32_t version;
704 	uint32_t maxlvt;
705 	register_t saveintr;
706 	int elvt_count;
707 	int i;
708 
709 	saveintr = intr_disable();
710 
711 	la = &lapics[lapic_id()];
712 	KASSERT(la->la_present, ("missing APIC structure"));
713 	version = lapic_read32(LAPIC_VERSION);
714 	maxlvt = (version & APIC_VER_MAXLVT) >> MAXLVTSHIFT;
715 
716 	/* Initialize the TPR to allow all interrupts. */
717 	lapic_set_tpr(0);
718 
719 	/* Setup spurious vector and enable the local APIC. */
720 	lapic_enable();
721 
722 	/* Program LINT[01] LVT entries. */
723 	lapic_write32(LAPIC_LVT_LINT0, lvt_mode(la, APIC_LVT_LINT0,
724 	    lapic_read32(LAPIC_LVT_LINT0)));
725 	lapic_write32(LAPIC_LVT_LINT1, lvt_mode(la, APIC_LVT_LINT1,
726 	    lapic_read32(LAPIC_LVT_LINT1)));
727 
728 	/* Program the PMC LVT entry if present. */
729 	if (maxlvt >= APIC_LVT_PMC) {
730 		lapic_write32(LAPIC_LVT_PCINT, lvt_mode(la, APIC_LVT_PMC,
731 		    LAPIC_LVT_PCINT));
732 	}
733 
734 	/*
735 	 * Program the timer LVT.  Calibration is deferred until it is certain
736 	 * that we have a reliable timecounter.
737 	 */
738 	la->lvt_timer_base = lvt_mode(la, APIC_LVT_TIMER,
739 	    lapic_read32(LAPIC_LVT_TIMER));
740 	la->lvt_timer_last = la->lvt_timer_base;
741 	lapic_write32(LAPIC_LVT_TIMER, la->lvt_timer_base);
742 
743 	if (boot)
744 		la->la_timer_mode = LAT_MODE_UNDEF;
745 	else if (la->la_timer_mode != LAT_MODE_UNDEF) {
746 		KASSERT(la->la_timer_period != 0, ("lapic%u: zero divisor",
747 		    lapic_id()));
748 		switch (la->la_timer_mode) {
749 		case LAT_MODE_PERIODIC:
750 			lapic_timer_set_divisor(lapic_timer_divisor);
751 			lapic_timer_periodic(la);
752 			break;
753 		case LAT_MODE_ONESHOT:
754 			lapic_timer_set_divisor(lapic_timer_divisor);
755 			lapic_timer_oneshot(la);
756 			break;
757 		case LAT_MODE_DEADLINE:
758 			lapic_timer_deadline(la);
759 			break;
760 		default:
761 			panic("corrupted la_timer_mode %p %d", la,
762 			    la->la_timer_mode);
763 		}
764 	}
765 
766 	/* Program error LVT and clear any existing errors. */
767 	lapic_write32(LAPIC_LVT_ERROR, lvt_mode(la, APIC_LVT_ERROR,
768 	    lapic_read32(LAPIC_LVT_ERROR)));
769 	lapic_write32(LAPIC_ESR, 0);
770 
771 	/* XXX: Thermal LVT */
772 
773 	/* Program the CMCI LVT entry if present. */
774 	if (maxlvt >= APIC_LVT_CMCI) {
775 		lapic_write32(LAPIC_LVT_CMCI, lvt_mode(la, APIC_LVT_CMCI,
776 		    lapic_read32(LAPIC_LVT_CMCI)));
777 	}
778 
779 	elvt_count = amd_read_elvt_count();
780 	for (i = 0; i < elvt_count; i++) {
781 		if (la->la_elvts[i].lvt_active)
782 			lapic_write32(LAPIC_EXT_LVT0 + i,
783 			    elvt_mode(la, i, lapic_read32(LAPIC_EXT_LVT0 + i)));
784 	}
785 
786 	intr_restore(saveintr);
787 }
788 
789 static void
lapic_intrcnt(void * dummy __unused)790 lapic_intrcnt(void *dummy __unused)
791 {
792 	struct pcpu *pc;
793 	struct lapic *la;
794 	char buf[MAXCOMLEN + 1];
795 
796 	/* If there are no APICs, skip this function. */
797 	if (lapics == NULL)
798 		return;
799 
800 	STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
801 		la = &lapics[pc->pc_apic_id];
802 		if (!la->la_present)
803 		    continue;
804 
805 		snprintf(buf, sizeof(buf), "cpu%d:timer", pc->pc_cpuid);
806 		intrcnt_add(buf, &la->la_timer_count);
807 	}
808 }
809 SYSINIT(lapic_intrcnt, SI_SUB_INTR, SI_ORDER_MIDDLE, lapic_intrcnt, NULL);
810 
811 void
lapic_reenable_pmc(void)812 lapic_reenable_pmc(void)
813 {
814 #ifdef HWPMC_HOOKS
815 	uint32_t value;
816 
817 	value = lapic_read32(LAPIC_LVT_PCINT);
818 	value &= ~APIC_LVT_M;
819 	lapic_write32(LAPIC_LVT_PCINT, value);
820 #endif
821 }
822 
823 #ifdef HWPMC_HOOKS
824 static void
lapic_update_pmc(void * dummy)825 lapic_update_pmc(void *dummy)
826 {
827 	struct lapic *la;
828 
829 	la = &lapics[lapic_id()];
830 	lapic_write32(LAPIC_LVT_PCINT, lvt_mode(la, APIC_LVT_PMC,
831 	    lapic_read32(LAPIC_LVT_PCINT)));
832 }
833 #endif
834 
835 void
lapic_calibrate_timer(void)836 lapic_calibrate_timer(void)
837 {
838 	struct lapic *la;
839 	register_t intr;
840 
841 #ifdef DEV_ATPIC
842 	/* Fail if the local APIC is not present. */
843 	if (!x2apic_mode && lapic_map == NULL)
844 		return;
845 #endif
846 
847 	intr = intr_disable();
848 	la = &lapics[lapic_id()];
849 
850 	lapic_calibrate_initcount(la);
851 
852 	intr_restore(intr);
853 
854 	if (lapic_timer_tsc_deadline && bootverbose) {
855 		printf("lapic: deadline tsc mode, Frequency %ju Hz\n",
856 		    (uintmax_t)tsc_freq);
857 	}
858 }
859 
860 int
lapic_enable_pmc(void)861 lapic_enable_pmc(void)
862 {
863 #ifdef HWPMC_HOOKS
864 	u_int32_t maxlvt;
865 
866 #ifdef DEV_ATPIC
867 	/* Fail if the local APIC is not present. */
868 	if (!x2apic_mode && lapic_map == NULL)
869 		return (0);
870 #endif
871 
872 	/* Fail if the PMC LVT is not present. */
873 	maxlvt = (lapic_read32(LAPIC_VERSION) & APIC_VER_MAXLVT) >> MAXLVTSHIFT;
874 	if (maxlvt < APIC_LVT_PMC)
875 		return (0);
876 
877 	lvts[APIC_LVT_PMC].lvt_masked = 0;
878 
879 	MPASS(mp_ncpus == 1 || smp_started);
880 	smp_rendezvous(NULL, lapic_update_pmc, NULL, NULL);
881 	return (1);
882 #else
883 	return (0);
884 #endif
885 }
886 
887 void
lapic_disable_pmc(void)888 lapic_disable_pmc(void)
889 {
890 #ifdef HWPMC_HOOKS
891 	u_int32_t maxlvt;
892 
893 #ifdef DEV_ATPIC
894 	/* Fail if the local APIC is not present. */
895 	if (!x2apic_mode && lapic_map == NULL)
896 		return;
897 #endif
898 
899 	/* Fail if the PMC LVT is not present. */
900 	maxlvt = (lapic_read32(LAPIC_VERSION) & APIC_VER_MAXLVT) >> MAXLVTSHIFT;
901 	if (maxlvt < APIC_LVT_PMC)
902 		return;
903 
904 	lvts[APIC_LVT_PMC].lvt_masked = 1;
905 
906 #ifdef SMP
907 	/* The APs should always be started when hwpmc is unloaded. */
908 	KASSERT(mp_ncpus == 1 || smp_started, ("hwpmc unloaded too early"));
909 #endif
910 	smp_rendezvous(NULL, lapic_update_pmc, NULL, NULL);
911 #endif
912 }
913 
914 static int
lapic_calibrate_initcount_cpuid_vm(void)915 lapic_calibrate_initcount_cpuid_vm(void)
916 {
917 	u_int regs[4];
918 	uint64_t freq;
919 
920 	/* Get value from CPUID leaf if possible. */
921 	if (vm_guest == VM_GUEST_NO)
922 		return (false);
923 	if (hv_high < 0x40000010)
924 		return (false);
925 	do_cpuid(0x40000010, regs);
926 	freq = (uint64_t)(regs[1]) * 1000;
927 
928 	/* Pick timer divisor. */
929 	lapic_timer_divisor = 2;
930 	do {
931 		if (freq / lapic_timer_divisor < APIC_TIMER_MAX_COUNT)
932 			break;
933 		lapic_timer_divisor <<= 1;
934 	} while (lapic_timer_divisor <= 128);
935 	if (lapic_timer_divisor > 128)
936 		return (false);
937 
938 	/* Record divided frequency. */
939 	count_freq = freq / lapic_timer_divisor;
940 	return (count_freq != 0);
941 }
942 
943 static uint64_t
cb_lapic_getcount(void)944 cb_lapic_getcount(void)
945 {
946 
947 	return (APIC_TIMER_MAX_COUNT - lapic_read32(LAPIC_CCR_TIMER));
948 }
949 
950 static void
lapic_calibrate_initcount(struct lapic * la)951 lapic_calibrate_initcount(struct lapic *la)
952 {
953 	uint64_t freq;
954 
955 	if (lapic_calibrate_initcount_cpuid_vm())
956 		goto done;
957 
958 	/* Calibrate the APIC timer frequency. */
959 	lapic_timer_set_divisor(2);
960 	lapic_timer_oneshot_nointr(la, APIC_TIMER_MAX_COUNT);
961 	fpu_kern_enter(curthread, NULL, FPU_KERN_NOCTX);
962 	freq = clockcalib(cb_lapic_getcount, "lapic");
963 	fpu_kern_leave(curthread, NULL);
964 
965 	/* Pick a different divisor if necessary. */
966 	lapic_timer_divisor = 2;
967 	do {
968 		if (freq * 2 / lapic_timer_divisor < APIC_TIMER_MAX_COUNT)
969 			break;
970 		lapic_timer_divisor <<= 1;
971 	} while (lapic_timer_divisor <= 128);
972 	if (lapic_timer_divisor > 128)
973 		panic("lapic: Divisor too big");
974 	count_freq = freq * 2 / lapic_timer_divisor;
975 done:
976 	if (bootverbose) {
977 		printf("lapic: Divisor %lu, Frequency %lu Hz\n",
978 		    lapic_timer_divisor, count_freq);
979 	}
980 }
981 
982 static void
lapic_change_mode(struct eventtimer * et,struct lapic * la,enum lat_timer_mode newmode)983 lapic_change_mode(struct eventtimer *et, struct lapic *la,
984     enum lat_timer_mode newmode)
985 {
986 	if (la->la_timer_mode == newmode)
987 		return;
988 	switch (newmode) {
989 	case LAT_MODE_PERIODIC:
990 		lapic_timer_set_divisor(lapic_timer_divisor);
991 		et->et_frequency = count_freq;
992 		break;
993 	case LAT_MODE_DEADLINE:
994 		et->et_frequency = tsc_freq;
995 		break;
996 	case LAT_MODE_ONESHOT:
997 		lapic_timer_set_divisor(lapic_timer_divisor);
998 		et->et_frequency = count_freq;
999 		break;
1000 	default:
1001 		panic("lapic_change_mode %d", newmode);
1002 	}
1003 	la->la_timer_mode = newmode;
1004 	et->et_min_period = (0x00000002LLU << 32) / et->et_frequency;
1005 	et->et_max_period = (0xfffffffeLLU << 32) / et->et_frequency;
1006 }
1007 
1008 static int
lapic_et_start(struct eventtimer * et,sbintime_t first,sbintime_t period)1009 lapic_et_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
1010 {
1011 	struct lapic *la;
1012 
1013 	la = &lapics[PCPU_GET(apic_id)];
1014 	if (period != 0) {
1015 		lapic_change_mode(et, la, LAT_MODE_PERIODIC);
1016 		la->la_timer_period = ((uint32_t)et->et_frequency * period) >>
1017 		    32;
1018 		lapic_timer_periodic(la);
1019 	} else if (lapic_timer_tsc_deadline) {
1020 		lapic_change_mode(et, la, LAT_MODE_DEADLINE);
1021 		la->la_timer_period = (et->et_frequency * first) >> 32;
1022 		lapic_timer_deadline(la);
1023 	} else {
1024 		lapic_change_mode(et, la, LAT_MODE_ONESHOT);
1025 		la->la_timer_period = ((uint32_t)et->et_frequency * first) >>
1026 		    32;
1027 		lapic_timer_oneshot(la);
1028 	}
1029 	return (0);
1030 }
1031 
1032 static int
lapic_et_stop(struct eventtimer * et)1033 lapic_et_stop(struct eventtimer *et)
1034 {
1035 	struct lapic *la;
1036 
1037 	la = &lapics[PCPU_GET(apic_id)];
1038 	lapic_timer_stop(la);
1039 	la->la_timer_mode = LAT_MODE_UNDEF;
1040 	return (0);
1041 }
1042 
1043 void
lapic_disable(void)1044 lapic_disable(void)
1045 {
1046 	uint32_t value;
1047 
1048 	/* Software disable the local APIC. */
1049 	value = lapic_read32(LAPIC_SVR);
1050 	value &= ~APIC_SVR_SWEN;
1051 	lapic_write32(LAPIC_SVR, value);
1052 }
1053 
1054 static void
lapic_enable(void)1055 lapic_enable(void)
1056 {
1057 	uint32_t value;
1058 
1059 	/* Program the spurious vector to enable the local APIC. */
1060 	value = lapic_read32(LAPIC_SVR);
1061 	value &= ~(APIC_SVR_VECTOR | APIC_SVR_FOCUS);
1062 	value |= APIC_SVR_FEN | APIC_SVR_SWEN | APIC_SPURIOUS_INT;
1063 	if (lapic_eoi_suppression)
1064 		value |= APIC_SVR_EOI_SUPPRESSION;
1065 	lapic_write32(LAPIC_SVR, value);
1066 }
1067 
1068 /* Reset the local APIC on the BSP during resume. */
1069 static void
lapic_resume(struct pic * pic,bool suspend_cancelled)1070 lapic_resume(struct pic *pic, bool suspend_cancelled)
1071 {
1072 
1073 	lapic_setup(0);
1074 }
1075 
1076 int
lapic_id(void)1077 lapic_id(void)
1078 {
1079 	uint32_t v;
1080 
1081 	KASSERT(x2apic_mode || lapic_map != NULL, ("local APIC is not mapped"));
1082 	v = lapic_read32(LAPIC_ID);
1083 	if (!x2apic_mode)
1084 		v >>= APIC_ID_SHIFT;
1085 	return (v);
1086 }
1087 
1088 int
lapic_intr_pending(u_int vector)1089 lapic_intr_pending(u_int vector)
1090 {
1091 	uint32_t irr;
1092 
1093 	/*
1094 	 * The IRR registers are an array of registers each of which
1095 	 * only describes 32 interrupts in the low 32 bits.  Thus, we
1096 	 * divide the vector by 32 to get the register index.
1097 	 * Finally, we modulus the vector by 32 to determine the
1098 	 * individual bit to test.
1099 	 */
1100 	irr = lapic_read32(LAPIC_IRR0 + vector / 32);
1101 	return (irr & 1 << (vector % 32));
1102 }
1103 
1104 void
lapic_set_logical_id(u_int apic_id,u_int cluster,u_int cluster_id)1105 lapic_set_logical_id(u_int apic_id, u_int cluster, u_int cluster_id)
1106 {
1107 	struct lapic *la;
1108 
1109 	KASSERT(lapics[apic_id].la_present, ("%s: APIC %u doesn't exist",
1110 	    __func__, apic_id));
1111 	KASSERT(cluster <= APIC_MAX_CLUSTER, ("%s: cluster %u too big",
1112 	    __func__, cluster));
1113 	KASSERT(cluster_id <= APIC_MAX_INTRACLUSTER_ID,
1114 	    ("%s: intra cluster id %u too big", __func__, cluster_id));
1115 	la = &lapics[apic_id];
1116 	la->la_cluster = cluster;
1117 	la->la_cluster_id = cluster_id;
1118 }
1119 
1120 int
lapic_set_lvt_mask(u_int apic_id,u_int pin,u_char masked)1121 lapic_set_lvt_mask(u_int apic_id, u_int pin, u_char masked)
1122 {
1123 
1124 	if (pin > APIC_LVT_MAX)
1125 		return (EINVAL);
1126 	if (apic_id == APIC_ID_ALL) {
1127 		lvts[pin].lvt_masked = masked;
1128 		if (bootverbose)
1129 			printf("lapic:");
1130 	} else {
1131 		KASSERT(lapics[apic_id].la_present,
1132 		    ("%s: missing APIC %u", __func__, apic_id));
1133 		lapics[apic_id].la_lvts[pin].lvt_masked = masked;
1134 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1135 		if (bootverbose)
1136 			printf("lapic%u:", apic_id);
1137 	}
1138 	if (bootverbose)
1139 		printf(" LINT%u %s\n", pin, masked ? "masked" : "unmasked");
1140 	return (0);
1141 }
1142 
1143 int
lapic_set_lvt_mode(u_int apic_id,u_int pin,u_int32_t mode)1144 lapic_set_lvt_mode(u_int apic_id, u_int pin, u_int32_t mode)
1145 {
1146 	struct lvt *lvt;
1147 
1148 	if (pin > APIC_LVT_MAX)
1149 		return (EINVAL);
1150 	if (apic_id == APIC_ID_ALL) {
1151 		lvt = &lvts[pin];
1152 		if (bootverbose)
1153 			printf("lapic:");
1154 	} else {
1155 		KASSERT(lapics[apic_id].la_present,
1156 		    ("%s: missing APIC %u", __func__, apic_id));
1157 		lvt = &lapics[apic_id].la_lvts[pin];
1158 		lvt->lvt_active = 1;
1159 		if (bootverbose)
1160 			printf("lapic%u:", apic_id);
1161 	}
1162 	lvt->lvt_mode = mode;
1163 	switch (mode) {
1164 	case APIC_LVT_DM_NMI:
1165 	case APIC_LVT_DM_SMI:
1166 	case APIC_LVT_DM_INIT:
1167 	case APIC_LVT_DM_EXTINT:
1168 		lvt->lvt_edgetrigger = 1;
1169 		lvt->lvt_activehi = 1;
1170 		if (mode == APIC_LVT_DM_EXTINT)
1171 			lvt->lvt_masked = 1;
1172 		else
1173 			lvt->lvt_masked = 0;
1174 		break;
1175 	default:
1176 		panic("Unsupported delivery mode: 0x%x\n", mode);
1177 	}
1178 	if (bootverbose) {
1179 		printf(" Routing ");
1180 		switch (mode) {
1181 		case APIC_LVT_DM_NMI:
1182 			printf("NMI");
1183 			break;
1184 		case APIC_LVT_DM_SMI:
1185 			printf("SMI");
1186 			break;
1187 		case APIC_LVT_DM_INIT:
1188 			printf("INIT");
1189 			break;
1190 		case APIC_LVT_DM_EXTINT:
1191 			printf("ExtINT");
1192 			break;
1193 		}
1194 		printf(" -> LINT%u\n", pin);
1195 	}
1196 	return (0);
1197 }
1198 
1199 int
lapic_set_lvt_polarity(u_int apic_id,u_int pin,enum intr_polarity pol)1200 lapic_set_lvt_polarity(u_int apic_id, u_int pin, enum intr_polarity pol)
1201 {
1202 
1203 	if (pin > APIC_LVT_MAX || pol == INTR_POLARITY_CONFORM)
1204 		return (EINVAL);
1205 	if (apic_id == APIC_ID_ALL) {
1206 		lvts[pin].lvt_activehi = (pol == INTR_POLARITY_HIGH);
1207 		if (bootverbose)
1208 			printf("lapic:");
1209 	} else {
1210 		KASSERT(lapics[apic_id].la_present,
1211 		    ("%s: missing APIC %u", __func__, apic_id));
1212 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1213 		lapics[apic_id].la_lvts[pin].lvt_activehi =
1214 		    (pol == INTR_POLARITY_HIGH);
1215 		if (bootverbose)
1216 			printf("lapic%u:", apic_id);
1217 	}
1218 	if (bootverbose)
1219 		printf(" LINT%u polarity: %s\n", pin,
1220 		    pol == INTR_POLARITY_HIGH ? "high" : "low");
1221 	return (0);
1222 }
1223 
1224 int
lapic_set_lvt_triggermode(u_int apic_id,u_int pin,enum intr_trigger trigger)1225 lapic_set_lvt_triggermode(u_int apic_id, u_int pin,
1226      enum intr_trigger trigger)
1227 {
1228 
1229 	if (pin > APIC_LVT_MAX || trigger == INTR_TRIGGER_CONFORM)
1230 		return (EINVAL);
1231 	if (apic_id == APIC_ID_ALL) {
1232 		lvts[pin].lvt_edgetrigger = (trigger == INTR_TRIGGER_EDGE);
1233 		if (bootverbose)
1234 			printf("lapic:");
1235 	} else {
1236 		KASSERT(lapics[apic_id].la_present,
1237 		    ("%s: missing APIC %u", __func__, apic_id));
1238 		lapics[apic_id].la_lvts[pin].lvt_edgetrigger =
1239 		    (trigger == INTR_TRIGGER_EDGE);
1240 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1241 		if (bootverbose)
1242 			printf("lapic%u:", apic_id);
1243 	}
1244 	if (bootverbose)
1245 		printf(" LINT%u trigger: %s\n", pin,
1246 		    trigger == INTR_TRIGGER_EDGE ? "edge" : "level");
1247 	return (0);
1248 }
1249 
1250 /*
1251  * Adjust the TPR of the current CPU so that it blocks all interrupts below
1252  * the passed in vector.
1253  */
1254 static void
lapic_set_tpr(u_int vector)1255 lapic_set_tpr(u_int vector)
1256 {
1257 #ifdef CHEAP_TPR
1258 	lapic_write32(LAPIC_TPR, vector);
1259 #else
1260 	uint32_t tpr;
1261 
1262 	tpr = lapic_read32(LAPIC_TPR) & ~APIC_TPR_PRIO;
1263 	tpr |= vector;
1264 	lapic_write32(LAPIC_TPR, tpr);
1265 #endif
1266 }
1267 
1268 void
lapic_eoi(void)1269 lapic_eoi(void)
1270 {
1271 
1272 	lapic_write32_nofence(LAPIC_EOI, 0);
1273 }
1274 
1275 void
lapic_handle_intr(int vector,struct trapframe * frame)1276 lapic_handle_intr(int vector, struct trapframe *frame)
1277 {
1278 	struct intsrc *isrc;
1279 
1280 	kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0);
1281 	kmsan_mark(&vector, sizeof(vector), KMSAN_STATE_INITED);
1282 	kmsan_mark(frame, sizeof(*frame), KMSAN_STATE_INITED);
1283 	trap_check_kstack();
1284 
1285 	isrc = intr_lookup_source(apic_idt_to_irq(PCPU_GET(apic_id),
1286 	    vector));
1287 	intr_execute_handlers(isrc, frame);
1288 }
1289 
1290 void
lapic_handle_timer(struct trapframe * frame)1291 lapic_handle_timer(struct trapframe *frame)
1292 {
1293 	struct lapic *la;
1294 	struct trapframe *oldframe;
1295 	struct thread *td;
1296 
1297 	/* Send EOI first thing. */
1298 	lapic_eoi();
1299 
1300 	kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0);
1301 	kmsan_mark(frame, sizeof(*frame), KMSAN_STATE_INITED);
1302 	trap_check_kstack();
1303 
1304 #if defined(SMP) && !defined(SCHED_ULE)
1305 	/*
1306 	 * Don't do any accounting for the disabled HTT cores, since it
1307 	 * will provide misleading numbers for the userland.
1308 	 *
1309 	 * No locking is necessary here, since even if we lose the race
1310 	 * when hlt_cpus_mask changes it is not a big deal, really.
1311 	 *
1312 	 * Don't do that for ULE, since ULE doesn't consider hlt_cpus_mask
1313 	 * and unlike other schedulers it actually schedules threads to
1314 	 * those CPUs.
1315 	 */
1316 	if (CPU_ISSET(PCPU_GET(cpuid), &hlt_cpus_mask))
1317 		return;
1318 #endif
1319 
1320 	/* Look up our local APIC structure for the tick counters. */
1321 	la = &lapics[PCPU_GET(apic_id)];
1322 	(*la->la_timer_count)++;
1323 	critical_enter();
1324 	if (lapic_et.et_active) {
1325 		td = curthread;
1326 		td->td_intr_nesting_level++;
1327 		oldframe = td->td_intr_frame;
1328 		td->td_intr_frame = frame;
1329 		lapic_et.et_event_cb(&lapic_et, lapic_et.et_arg);
1330 		td->td_intr_frame = oldframe;
1331 		td->td_intr_nesting_level--;
1332 	}
1333 	critical_exit();
1334 }
1335 
1336 static void
lapic_timer_set_divisor(u_int divisor)1337 lapic_timer_set_divisor(u_int divisor)
1338 {
1339 
1340 	KASSERT(powerof2(divisor), ("lapic: invalid divisor %u", divisor));
1341 	KASSERT(ffs(divisor) <= nitems(lapic_timer_divisors),
1342 		("lapic: invalid divisor %u", divisor));
1343 	lapic_write32(LAPIC_DCR_TIMER, lapic_timer_divisors[ffs(divisor) - 1]);
1344 }
1345 
1346 static void
lapic_timer_oneshot(struct lapic * la)1347 lapic_timer_oneshot(struct lapic *la)
1348 {
1349 	uint32_t value;
1350 
1351 	value = la->lvt_timer_base;
1352 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1353 	value |= APIC_LVTT_TM_ONE_SHOT;
1354 	la->lvt_timer_last = value;
1355 	lapic_write32(LAPIC_LVT_TIMER, value);
1356 	lapic_write32(LAPIC_ICR_TIMER, la->la_timer_period);
1357 }
1358 
1359 static void
lapic_timer_oneshot_nointr(struct lapic * la,uint32_t count)1360 lapic_timer_oneshot_nointr(struct lapic *la, uint32_t count)
1361 {
1362 	uint32_t value;
1363 
1364 	value = la->lvt_timer_base;
1365 	value &= ~APIC_LVTT_TM;
1366 	value |= APIC_LVTT_TM_ONE_SHOT | APIC_LVT_M;
1367 	la->lvt_timer_last = value;
1368 	lapic_write32(LAPIC_LVT_TIMER, value);
1369 	lapic_write32(LAPIC_ICR_TIMER, count);
1370 }
1371 
1372 static void
lapic_timer_periodic(struct lapic * la)1373 lapic_timer_periodic(struct lapic *la)
1374 {
1375 	uint32_t value;
1376 
1377 	value = la->lvt_timer_base;
1378 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1379 	value |= APIC_LVTT_TM_PERIODIC;
1380 	la->lvt_timer_last = value;
1381 	lapic_write32(LAPIC_LVT_TIMER, value);
1382 	lapic_write32(LAPIC_ICR_TIMER, la->la_timer_period);
1383 }
1384 
1385 static void
lapic_timer_deadline(struct lapic * la)1386 lapic_timer_deadline(struct lapic *la)
1387 {
1388 	uint32_t value;
1389 
1390 	value = la->lvt_timer_base;
1391 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1392 	value |= APIC_LVTT_TM_TSCDLT;
1393 	if (value != la->lvt_timer_last) {
1394 		la->lvt_timer_last = value;
1395 		lapic_write32_nofence(LAPIC_LVT_TIMER, value);
1396 		if (!x2apic_mode)
1397 			mfence();
1398 	}
1399 	wrmsr(MSR_TSC_DEADLINE, la->la_timer_period + rdtsc());
1400 }
1401 
1402 static void
lapic_timer_stop(struct lapic * la)1403 lapic_timer_stop(struct lapic *la)
1404 {
1405 	uint32_t value;
1406 
1407 	if (la->la_timer_mode == LAT_MODE_DEADLINE) {
1408 		wrmsr(MSR_TSC_DEADLINE, 0);
1409 		mfence();
1410 	} else {
1411 		value = la->lvt_timer_base;
1412 		value &= ~APIC_LVTT_TM;
1413 		value |= APIC_LVT_M;
1414 		la->lvt_timer_last = value;
1415 		lapic_write32(LAPIC_LVT_TIMER, value);
1416 	}
1417 }
1418 
1419 void
lapic_handle_cmc(void)1420 lapic_handle_cmc(void)
1421 {
1422 	trap_check_kstack();
1423 
1424 	lapic_eoi();
1425 	cmc_intr();
1426 }
1427 
1428 /*
1429  * Called from the mca_init() to activate the CMC interrupt if this CPU is
1430  * responsible for monitoring any MC banks for CMC events.  Since mca_init()
1431  * is called prior to lapic_setup() during boot, this just needs to unmask
1432  * this CPU's LVT_CMCI entry.
1433  */
1434 void
lapic_enable_cmc(void)1435 lapic_enable_cmc(void)
1436 {
1437 	u_int apic_id;
1438 
1439 #ifdef DEV_ATPIC
1440 	if (!x2apic_mode && lapic_map == NULL)
1441 		return;
1442 #endif
1443 	apic_id = PCPU_GET(apic_id);
1444 	KASSERT(lapics[apic_id].la_present,
1445 	    ("%s: missing APIC %u", __func__, apic_id));
1446 	lapics[apic_id].la_lvts[APIC_LVT_CMCI].lvt_masked = 0;
1447 	lapics[apic_id].la_lvts[APIC_LVT_CMCI].lvt_active = 1;
1448 }
1449 
1450 int
lapic_enable_mca_elvt(void)1451 lapic_enable_mca_elvt(void)
1452 {
1453 	u_int apic_id;
1454 	uint32_t value;
1455 	int elvt_count;
1456 
1457 #ifdef DEV_ATPIC
1458 	if (lapic_map == NULL)
1459 		return (-1);
1460 #endif
1461 
1462 	apic_id = PCPU_GET(apic_id);
1463 	KASSERT(lapics[apic_id].la_present,
1464 	    ("%s: missing APIC %u", __func__, apic_id));
1465 	elvt_count = amd_read_elvt_count();
1466 	if (elvt_count <= APIC_ELVT_MCA)
1467 		return (-1);
1468 
1469 	value = lapic_read32(LAPIC_EXT_LVT0 + APIC_ELVT_MCA);
1470 	if ((value & APIC_LVT_M) == 0) {
1471 		if (bootverbose)
1472 			printf("AMD MCE Thresholding Extended LVT is already active\n");
1473 		return (APIC_ELVT_MCA);
1474 	}
1475 	lapics[apic_id].la_elvts[APIC_ELVT_MCA].lvt_masked = 0;
1476 	lapics[apic_id].la_elvts[APIC_ELVT_MCA].lvt_active = 1;
1477 	return (APIC_ELVT_MCA);
1478 }
1479 
1480 void
lapic_handle_error(void)1481 lapic_handle_error(void)
1482 {
1483 	uint32_t esr;
1484 
1485 	trap_check_kstack();
1486 
1487 	/*
1488 	 * Read the contents of the error status register.  Write to
1489 	 * the register first before reading from it to force the APIC
1490 	 * to update its value to indicate any errors that have
1491 	 * occurred since the previous write to the register.
1492 	 */
1493 	lapic_write32(LAPIC_ESR, 0);
1494 	esr = lapic_read32(LAPIC_ESR);
1495 
1496 	printf("CPU%d: local APIC error 0x%x\n", PCPU_GET(cpuid), esr);
1497 	lapic_eoi();
1498 }
1499 
1500 u_int
apic_cpuid(u_int apic_id)1501 apic_cpuid(u_int apic_id)
1502 {
1503 #ifdef SMP
1504 	return apic_cpuids[apic_id];
1505 #else
1506 	return 0;
1507 #endif
1508 }
1509 
1510 /* Request a free IDT vector to be used by the specified IRQ. */
1511 u_int
apic_alloc_vector(u_int apic_id,u_int irq)1512 apic_alloc_vector(u_int apic_id, u_int irq)
1513 {
1514 	u_int vector;
1515 
1516 	KASSERT(irq < num_io_irqs, ("Invalid IRQ %u", irq));
1517 
1518 	/*
1519 	 * Search for a free vector.  Currently we just use a very simple
1520 	 * algorithm to find the first free vector.
1521 	 */
1522 	mtx_lock_spin(&icu_lock);
1523 	for (vector = 0; vector < APIC_NUM_IOINTS; vector++) {
1524 		if (lapics[apic_id].la_ioint_irqs[vector] != IRQ_FREE)
1525 			continue;
1526 		lapics[apic_id].la_ioint_irqs[vector] = irq;
1527 		mtx_unlock_spin(&icu_lock);
1528 		return (vector + APIC_IO_INTS);
1529 	}
1530 	mtx_unlock_spin(&icu_lock);
1531 	return (0);
1532 }
1533 
1534 /*
1535  * Request 'count' free contiguous IDT vectors to be used by 'count'
1536  * IRQs.  'count' must be a power of two and the vectors will be
1537  * aligned on a boundary of 'align'.  If the request cannot be
1538  * satisfied, 0 is returned.
1539  */
1540 u_int
apic_alloc_vectors(u_int apic_id,u_int * irqs,u_int count,u_int align)1541 apic_alloc_vectors(u_int apic_id, u_int *irqs, u_int count, u_int align)
1542 {
1543 	u_int first, run, vector;
1544 
1545 	KASSERT(powerof2(count), ("bad count"));
1546 	KASSERT(powerof2(align), ("bad align"));
1547 	KASSERT(align >= count, ("align < count"));
1548 #ifdef INVARIANTS
1549 	for (run = 0; run < count; run++)
1550 		KASSERT(irqs[run] < num_io_irqs, ("Invalid IRQ %u at index %u",
1551 		    irqs[run], run));
1552 #endif
1553 
1554 	/*
1555 	 * Search for 'count' free vectors.  As with apic_alloc_vector(),
1556 	 * this just uses a simple first fit algorithm.
1557 	 */
1558 	run = 0;
1559 	first = 0;
1560 	mtx_lock_spin(&icu_lock);
1561 	for (vector = 0; vector < APIC_NUM_IOINTS; vector++) {
1562 		/* Vector is in use, end run. */
1563 		if (lapics[apic_id].la_ioint_irqs[vector] != IRQ_FREE) {
1564 			run = 0;
1565 			first = 0;
1566 			continue;
1567 		}
1568 
1569 		/* Start a new run if run == 0 and vector is aligned. */
1570 		if (run == 0) {
1571 			if (((vector + APIC_IO_INTS) & (align - 1)) != 0)
1572 				continue;
1573 			first = vector;
1574 		}
1575 		run++;
1576 
1577 		/* Keep looping if the run isn't long enough yet. */
1578 		if (run < count)
1579 			continue;
1580 
1581 		/* Found a run, assign IRQs and return the first vector. */
1582 		for (vector = 0; vector < count; vector++)
1583 			lapics[apic_id].la_ioint_irqs[first + vector] =
1584 			    irqs[vector];
1585 		mtx_unlock_spin(&icu_lock);
1586 		return (first + APIC_IO_INTS);
1587 	}
1588 	mtx_unlock_spin(&icu_lock);
1589 	printf("APIC: Couldn't find APIC vectors for %u IRQs\n", count);
1590 	return (0);
1591 }
1592 
1593 /*
1594  * Enable a vector for a particular apic_id.  Since all lapics share idt
1595  * entries and ioint_handlers this enables the vector on all lapics.  lapics
1596  * which do not have the vector configured would report spurious interrupts
1597  * should it fire.
1598  */
1599 void
apic_enable_vector(u_int apic_id,u_int vector)1600 apic_enable_vector(u_int apic_id, u_int vector)
1601 {
1602 
1603 	KASSERT(vector != IDT_SYSCALL, ("Attempt to overwrite syscall entry"));
1604 	KASSERT(ioint_handlers[vector / 32] != NULL,
1605 	    ("No ISR handler for vector %u", vector));
1606 #ifdef KDTRACE_HOOKS
1607 	KASSERT(vector != IDT_DTRACE_RET,
1608 	    ("Attempt to overwrite DTrace entry"));
1609 #endif
1610 	setidt(vector, (pti ? ioint_pti_handlers : ioint_handlers)[vector / 32],
1611 	    SDT_APIC, SEL_KPL, GSEL_APIC);
1612 }
1613 
1614 void
apic_disable_vector(u_int apic_id,u_int vector)1615 apic_disable_vector(u_int apic_id, u_int vector)
1616 {
1617 
1618 	KASSERT(vector != IDT_SYSCALL, ("Attempt to overwrite syscall entry"));
1619 #ifdef KDTRACE_HOOKS
1620 	KASSERT(vector != IDT_DTRACE_RET,
1621 	    ("Attempt to overwrite DTrace entry"));
1622 #endif
1623 	KASSERT(ioint_handlers[vector / 32] != NULL,
1624 	    ("No ISR handler for vector %u", vector));
1625 #ifdef notyet
1626 	/*
1627 	 * We can not currently clear the idt entry because other cpus
1628 	 * may have a valid vector at this offset.
1629 	 */
1630 	setidt(vector, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd), SDT_APIC,
1631 	    SEL_KPL, GSEL_APIC);
1632 #endif
1633 }
1634 
1635 /* Release an APIC vector when it's no longer in use. */
1636 void
apic_free_vector(u_int apic_id,u_int vector,u_int irq)1637 apic_free_vector(u_int apic_id, u_int vector, u_int irq)
1638 {
1639 	struct thread *td;
1640 
1641 	KASSERT(vector >= APIC_IO_INTS && vector != IDT_SYSCALL &&
1642 	    vector <= APIC_IO_INTS + APIC_NUM_IOINTS,
1643 	    ("Vector %u does not map to an IRQ line", vector));
1644 	KASSERT(irq < num_io_irqs, ("Invalid IRQ %u", irq));
1645 	KASSERT(lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS] ==
1646 	    irq, ("IRQ mismatch"));
1647 #ifdef KDTRACE_HOOKS
1648 	KASSERT(vector != IDT_DTRACE_RET,
1649 	    ("Attempt to overwrite DTrace entry"));
1650 #endif
1651 
1652 	/*
1653 	 * Bind us to the cpu that owned the vector before freeing it so
1654 	 * we don't lose an interrupt delivery race.
1655 	 */
1656 	td = curthread;
1657 	if (!rebooting) {
1658 		thread_lock(td);
1659 		if (sched_is_bound(td))
1660 			panic("apic_free_vector: Thread already bound.\n");
1661 		sched_bind(td, apic_cpuid(apic_id));
1662 		thread_unlock(td);
1663 	}
1664 	mtx_lock_spin(&icu_lock);
1665 	lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS] = IRQ_FREE;
1666 	mtx_unlock_spin(&icu_lock);
1667 	if (!rebooting) {
1668 		thread_lock(td);
1669 		sched_unbind(td);
1670 		thread_unlock(td);
1671 	}
1672 }
1673 
1674 /* Map an IDT vector (APIC) to an IRQ (interrupt source). */
1675 static u_int
apic_idt_to_irq(u_int apic_id,u_int vector)1676 apic_idt_to_irq(u_int apic_id, u_int vector)
1677 {
1678 	int irq;
1679 
1680 	KASSERT(vector >= APIC_IO_INTS && vector != IDT_SYSCALL &&
1681 	    vector <= APIC_IO_INTS + APIC_NUM_IOINTS,
1682 	    ("Vector %u does not map to an IRQ line", vector));
1683 #ifdef KDTRACE_HOOKS
1684 	KASSERT(vector != IDT_DTRACE_RET,
1685 	    ("Attempt to overwrite DTrace entry"));
1686 #endif
1687 	irq = lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS];
1688 	if (irq < 0)
1689 		irq = 0;
1690 	return (irq);
1691 }
1692 
1693 #ifdef DDB
1694 /*
1695  * Dump data about APIC IDT vector mappings.
1696  */
DB_SHOW_COMMAND_FLAGS(apic,db_show_apic,DB_CMD_MEMSAFE)1697 DB_SHOW_COMMAND_FLAGS(apic, db_show_apic, DB_CMD_MEMSAFE)
1698 {
1699 	struct intsrc *isrc;
1700 	int i, verbose;
1701 	u_int apic_id;
1702 	u_int irq;
1703 
1704 	if (strcmp(modif, "vv") == 0)
1705 		verbose = 2;
1706 	else if (strcmp(modif, "v") == 0)
1707 		verbose = 1;
1708 	else
1709 		verbose = 0;
1710 	for (apic_id = 0; apic_id <= max_apic_id; apic_id++) {
1711 		if (lapics[apic_id].la_present == 0)
1712 			continue;
1713 		db_printf("Interrupts bound to lapic %u\n", apic_id);
1714 		for (i = 0; i < APIC_NUM_IOINTS + 1 && !db_pager_quit; i++) {
1715 			irq = lapics[apic_id].la_ioint_irqs[i];
1716 			if (irq == IRQ_FREE || irq == IRQ_SYSCALL)
1717 				continue;
1718 #ifdef KDTRACE_HOOKS
1719 			if (irq == IRQ_DTRACE_RET)
1720 				continue;
1721 #endif
1722 #ifdef XENHVM
1723 			if (irq == IRQ_EVTCHN)
1724 				continue;
1725 #endif
1726 			db_printf("vec 0x%2x -> ", i + APIC_IO_INTS);
1727 			if (irq == IRQ_TIMER)
1728 				db_printf("lapic timer\n");
1729 			else if (irq < num_io_irqs) {
1730 				isrc = intr_lookup_source(irq);
1731 				if (isrc == NULL || verbose == 0)
1732 					db_printf("IRQ %u\n", irq);
1733 				else
1734 					db_dump_intr_event(isrc->is_event,
1735 					    verbose == 2);
1736 			} else
1737 				db_printf("IRQ %u ???\n", irq);
1738 		}
1739 	}
1740 }
1741 
1742 static void
dump_mask(const char * prefix,uint32_t v,int base)1743 dump_mask(const char *prefix, uint32_t v, int base)
1744 {
1745 	int i, first;
1746 
1747 	first = 1;
1748 	for (i = 0; i < 32; i++)
1749 		if (v & (1 << i)) {
1750 			if (first) {
1751 				db_printf("%s:", prefix);
1752 				first = 0;
1753 			}
1754 			db_printf(" %02x", base + i);
1755 		}
1756 	if (!first)
1757 		db_printf("\n");
1758 }
1759 
1760 /* Show info from the lapic regs for this CPU. */
DB_SHOW_COMMAND_FLAGS(lapic,db_show_lapic,DB_CMD_MEMSAFE)1761 DB_SHOW_COMMAND_FLAGS(lapic, db_show_lapic, DB_CMD_MEMSAFE)
1762 {
1763 	uint32_t v;
1764 
1765 	db_printf("lapic ID = %d\n", lapic_id());
1766 	v = lapic_read32(LAPIC_VERSION);
1767 	db_printf("version  = %d.%d\n", (v & APIC_VER_VERSION) >> 4,
1768 	    v & 0xf);
1769 	db_printf("max LVT  = %d\n", (v & APIC_VER_MAXLVT) >> MAXLVTSHIFT);
1770 	v = lapic_read32(LAPIC_SVR);
1771 	db_printf("SVR      = %02x (%s)\n", v & APIC_SVR_VECTOR,
1772 	    v & APIC_SVR_ENABLE ? "enabled" : "disabled");
1773 	db_printf("TPR      = %02x\n", lapic_read32(LAPIC_TPR));
1774 
1775 #define dump_field(prefix, regn, index)					\
1776 	dump_mask(__XSTRING(prefix ## index), 				\
1777 	    lapic_read32(LAPIC_ ## regn ## index),			\
1778 	    index * 32)
1779 
1780 	db_printf("In-service Interrupts:\n");
1781 	dump_field(isr, ISR, 0);
1782 	dump_field(isr, ISR, 1);
1783 	dump_field(isr, ISR, 2);
1784 	dump_field(isr, ISR, 3);
1785 	dump_field(isr, ISR, 4);
1786 	dump_field(isr, ISR, 5);
1787 	dump_field(isr, ISR, 6);
1788 	dump_field(isr, ISR, 7);
1789 
1790 	db_printf("TMR Interrupts:\n");
1791 	dump_field(tmr, TMR, 0);
1792 	dump_field(tmr, TMR, 1);
1793 	dump_field(tmr, TMR, 2);
1794 	dump_field(tmr, TMR, 3);
1795 	dump_field(tmr, TMR, 4);
1796 	dump_field(tmr, TMR, 5);
1797 	dump_field(tmr, TMR, 6);
1798 	dump_field(tmr, TMR, 7);
1799 
1800 	db_printf("IRR Interrupts:\n");
1801 	dump_field(irr, IRR, 0);
1802 	dump_field(irr, IRR, 1);
1803 	dump_field(irr, IRR, 2);
1804 	dump_field(irr, IRR, 3);
1805 	dump_field(irr, IRR, 4);
1806 	dump_field(irr, IRR, 5);
1807 	dump_field(irr, IRR, 6);
1808 	dump_field(irr, IRR, 7);
1809 
1810 #undef dump_field
1811 }
1812 #endif
1813 
1814 /*
1815  * APIC probing support code.  This includes code to manage enumerators.
1816  */
1817 
1818 static SLIST_HEAD(, apic_enumerator) enumerators =
1819 	SLIST_HEAD_INITIALIZER(enumerators);
1820 static struct apic_enumerator *best_enum;
1821 
1822 void
apic_register_enumerator(struct apic_enumerator * enumerator)1823 apic_register_enumerator(struct apic_enumerator *enumerator)
1824 {
1825 #ifdef INVARIANTS
1826 	struct apic_enumerator *apic_enum;
1827 
1828 	SLIST_FOREACH(apic_enum, &enumerators, apic_next) {
1829 		if (apic_enum == enumerator)
1830 			panic("%s: Duplicate register of %s", __func__,
1831 			    enumerator->apic_name);
1832 	}
1833 #endif
1834 	SLIST_INSERT_HEAD(&enumerators, enumerator, apic_next);
1835 }
1836 
1837 /*
1838  * We have to look for CPU's very, very early because certain subsystems
1839  * want to know how many CPU's we have extremely early on in the boot
1840  * process.
1841  */
1842 static void
apic_init(void * dummy __unused)1843 apic_init(void *dummy __unused)
1844 {
1845 	struct apic_enumerator *enumerator;
1846 	int retval, best;
1847 
1848 	/* We only support built in local APICs. */
1849 	if (!(cpu_feature & CPUID_APIC))
1850 		return;
1851 
1852 	/* Don't probe if APIC mode is disabled. */
1853 	if (resource_disabled("apic", 0))
1854 		return;
1855 
1856 	/* Probe all the enumerators to find the best match. */
1857 	best_enum = NULL;
1858 	best = 0;
1859 	SLIST_FOREACH(enumerator, &enumerators, apic_next) {
1860 		retval = enumerator->apic_probe();
1861 		if (retval > 0)
1862 			continue;
1863 		if (best_enum == NULL || best < retval) {
1864 			best_enum = enumerator;
1865 			best = retval;
1866 		}
1867 	}
1868 	if (best_enum == NULL) {
1869 		if (bootverbose)
1870 			printf("APIC: Could not find any APICs.\n");
1871 #ifndef DEV_ATPIC
1872 		panic("running without device atpic requires a local APIC");
1873 #endif
1874 		return;
1875 	}
1876 
1877 	if (bootverbose)
1878 		printf("APIC: Using the %s enumerator.\n",
1879 		    best_enum->apic_name);
1880 
1881 #ifdef I686_CPU
1882 	/*
1883 	 * To work around an errata, we disable the local APIC on some
1884 	 * CPUs during early startup.  We need to turn the local APIC back
1885 	 * on on such CPUs now.
1886 	 */
1887 	ppro_reenable_apic();
1888 #endif
1889 
1890 	/* Probe the CPU's in the system. */
1891 	retval = best_enum->apic_probe_cpus();
1892 	if (retval != 0)
1893 		printf("%s: Failed to probe CPUs: returned %d\n",
1894 		    best_enum->apic_name, retval);
1895 
1896 }
1897 SYSINIT(apic_init, SI_SUB_TUNABLES - 1, SI_ORDER_SECOND, apic_init, NULL);
1898 
1899 /*
1900  * Setup the local APIC.  We have to do this prior to starting up the APs
1901  * in the SMP case.
1902  */
1903 static void
apic_setup_local(void * dummy __unused)1904 apic_setup_local(void *dummy __unused)
1905 {
1906 	int retval;
1907 
1908 	if (best_enum == NULL)
1909 		return;
1910 
1911 	lapics = malloc(sizeof(*lapics) * (max_apic_id + 1), M_LAPIC,
1912 	    M_WAITOK | M_ZERO);
1913 
1914 	/* Initialize the local APIC. */
1915 	retval = best_enum->apic_setup_local();
1916 	if (retval != 0)
1917 		printf("%s: Failed to setup the local APIC: returned %d\n",
1918 		    best_enum->apic_name, retval);
1919 }
1920 SYSINIT(apic_setup_local, SI_SUB_CPU, SI_ORDER_SECOND, apic_setup_local, NULL);
1921 
1922 /*
1923  * Setup the I/O APICs.
1924  */
1925 static void
apic_setup_io(void * dummy __unused)1926 apic_setup_io(void *dummy __unused)
1927 {
1928 	int retval;
1929 
1930 	if (best_enum == NULL)
1931 		return;
1932 
1933 	/*
1934 	 * Local APIC must be registered before other PICs and pseudo PICs
1935 	 * for proper suspend/resume order.
1936 	 */
1937 	intr_register_pic(&lapic_pic);
1938 
1939 	retval = best_enum->apic_setup_io();
1940 	if (retval != 0)
1941 		printf("%s: Failed to setup I/O APICs: returned %d\n",
1942 		    best_enum->apic_name, retval);
1943 
1944 	/*
1945 	 * Finish setting up the local APIC on the BSP once we know
1946 	 * how to properly program the LINT pins.  In particular, this
1947 	 * enables the EOI suppression mode, if LAPIC supports it and
1948 	 * user did not disable the mode.
1949 	 */
1950 	lapic_setup(1);
1951 	if (bootverbose)
1952 		lapic_dump("BSP");
1953 
1954 	/* Enable the MSI "pic". */
1955 	msi_init();
1956 
1957 #ifdef XENHVM
1958 	xen_intr_alloc_irqs();
1959 #endif
1960 }
1961 SYSINIT(apic_setup_io, SI_SUB_INTR, SI_ORDER_THIRD, apic_setup_io, NULL);
1962 
1963 #ifdef SMP
1964 /*
1965  * Inter Processor Interrupt functions.  The lapic_ipi_*() functions are
1966  * private to the MD code.  The public interface for the rest of the
1967  * kernel is defined in mp_machdep.c.
1968  */
1969 
1970 /*
1971  * Wait delay microseconds for IPI to be sent.  If delay is -1, we
1972  * wait forever.
1973  */
1974 int
lapic_ipi_wait(int delay)1975 lapic_ipi_wait(int delay)
1976 {
1977 	uint64_t rx;
1978 
1979 	/* LAPIC_ICR.APIC_DELSTAT_MASK is undefined in x2APIC mode */
1980 	if (x2apic_mode)
1981 		return (1);
1982 
1983 	for (rx = 0; delay == -1 || rx < lapic_ipi_wait_mult * delay; rx++) {
1984 		if ((lapic_read_icr_lo() & APIC_DELSTAT_MASK) ==
1985 		    APIC_DELSTAT_IDLE)
1986 			return (1);
1987 		ia32_pause();
1988 	}
1989 	return (0);
1990 }
1991 
1992 void
lapic_ipi_raw(register_t icrlo,u_int dest)1993 lapic_ipi_raw(register_t icrlo, u_int dest)
1994 {
1995 	uint32_t icrhi;
1996 
1997 	/* XXX: Need more sanity checking of icrlo? */
1998 	KASSERT(x2apic_mode || lapic_map != NULL,
1999 	    ("%s called too early", __func__));
2000 	KASSERT(x2apic_mode ||
2001 	    (dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
2002 	    ("%s: invalid dest field", __func__));
2003 	KASSERT((icrlo & APIC_ICRLO_RESV_MASK) == 0,
2004 	    ("%s: reserved bits set in ICR LO register", __func__));
2005 
2006 	if ((icrlo & APIC_DEST_MASK) == APIC_DEST_DESTFLD) {
2007 		if (x2apic_mode)
2008 			icrhi = dest;
2009 		else
2010 			icrhi = dest << APIC_ID_SHIFT;
2011 		lapic_write_icr(icrhi, icrlo);
2012 	} else {
2013 		lapic_write_icr_lo(icrlo);
2014 	}
2015 }
2016 
2017 #ifdef DETECT_DEADLOCK
2018 #define	AFTER_SPIN	50
2019 #endif
2020 
2021 static void
native_lapic_ipi_vectored(u_int vector,int dest)2022 native_lapic_ipi_vectored(u_int vector, int dest)
2023 {
2024 	register_t icrlo, destfield;
2025 
2026 	KASSERT((vector & ~APIC_VECTOR_MASK) == 0,
2027 	    ("%s: invalid vector %d", __func__, vector));
2028 
2029 	destfield = 0;
2030 	switch (dest) {
2031 	case APIC_IPI_DEST_SELF:
2032 		if (x2apic_mode && vector < IPI_NMI_FIRST) {
2033 			lapic_write_self_ipi(vector);
2034 			return;
2035 		}
2036 		icrlo = APIC_DEST_SELF;
2037 		break;
2038 	case APIC_IPI_DEST_ALL:
2039 		icrlo = APIC_DEST_ALLISELF;
2040 		break;
2041 	case APIC_IPI_DEST_OTHERS:
2042 		icrlo = APIC_DEST_ALLESELF;
2043 		break;
2044 	default:
2045 		icrlo = 0;
2046 		KASSERT(x2apic_mode ||
2047 		    (dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
2048 		    ("%s: invalid destination 0x%x", __func__, dest));
2049 		destfield = dest;
2050 	}
2051 
2052 	/*
2053 	 * NMI IPIs are just fake vectors used to send a NMI.  Use special rules
2054 	 * regarding NMIs if passed, otherwise specify the vector.
2055 	 */
2056 	if (vector >= IPI_NMI_FIRST)
2057 		icrlo |= APIC_DELMODE_NMI;
2058 	else
2059 		icrlo |= vector | APIC_DELMODE_FIXED;
2060 	icrlo |= APIC_DESTMODE_PHY | APIC_TRIGMOD_EDGE | APIC_LEVEL_ASSERT;
2061 
2062 	/* Wait for an earlier IPI to finish. */
2063 	if (!lapic_ipi_wait(lapic_ds_idle_timeout)) {
2064 		if (KERNEL_PANICKED())
2065 			return;
2066 		else
2067 			panic("APIC: Previous IPI is stuck");
2068 	}
2069 
2070 	lapic_ipi_raw(icrlo, destfield);
2071 
2072 #ifdef DETECT_DEADLOCK
2073 	/* Wait for IPI to be delivered. */
2074 	if (!lapic_ipi_wait(AFTER_SPIN)) {
2075 #ifdef needsattention
2076 		/*
2077 		 * XXX FIXME:
2078 		 *
2079 		 * The above function waits for the message to actually be
2080 		 * delivered.  It breaks out after an arbitrary timeout
2081 		 * since the message should eventually be delivered (at
2082 		 * least in theory) and that if it wasn't we would catch
2083 		 * the failure with the check above when the next IPI is
2084 		 * sent.
2085 		 *
2086 		 * We could skip this wait entirely, EXCEPT it probably
2087 		 * protects us from other routines that assume that the
2088 		 * message was delivered and acted upon when this function
2089 		 * returns.
2090 		 */
2091 		printf("APIC: IPI might be stuck\n");
2092 #else /* !needsattention */
2093 		/* Wait until mesage is sent without a timeout. */
2094 		while (lapic_read_icr_lo() & APIC_DELSTAT_PEND)
2095 			ia32_pause();
2096 #endif /* needsattention */
2097 	}
2098 #endif /* DETECT_DEADLOCK */
2099 }
2100 
2101 void (*ipi_vectored)(u_int, int) = &native_lapic_ipi_vectored;
2102 #endif /* SMP */
2103 
2104 /*
2105  * Since the IDT is shared by all CPUs the IPI slot update needs to be globally
2106  * visible.
2107  *
2108  * Consider the case where an IPI is generated immediately after allocation:
2109  *     vector = lapic_ipi_alloc(ipifunc);
2110  *     ipi_selected(other_cpus, vector);
2111  *
2112  * In xAPIC mode a write to ICR_LO has serializing semantics because the
2113  * APIC page is mapped as an uncached region. In x2APIC mode there is an
2114  * explicit 'mfence' before the ICR MSR is written. Therefore in both cases
2115  * the IDT slot update is globally visible before the IPI is delivered.
2116  */
2117 int
lapic_ipi_alloc(inthand_t * ipifunc)2118 lapic_ipi_alloc(inthand_t *ipifunc)
2119 {
2120 	struct gate_descriptor *ip;
2121 	long func;
2122 	int idx, vector;
2123 
2124 	KASSERT(ipifunc != &IDTVEC(rsvd) && ipifunc != &IDTVEC(rsvd_pti),
2125 	    ("invalid ipifunc %p", ipifunc));
2126 
2127 	vector = -1;
2128 	mtx_lock_spin(&icu_lock);
2129 	for (idx = IPI_DYN_FIRST; idx <= IPI_DYN_LAST; idx++) {
2130 		ip = &idt[idx];
2131 		func = (ip->gd_hioffset << 16) | ip->gd_looffset;
2132 #ifdef __i386__
2133 		func -= setidt_disp;
2134 #endif
2135 		if ((!pti && func == (uintptr_t)&IDTVEC(rsvd)) ||
2136 		    (pti && func == (uintptr_t)&IDTVEC(rsvd_pti))) {
2137 			vector = idx;
2138 			setidt(vector, ipifunc, SDT_APIC, SEL_KPL, GSEL_APIC);
2139 			break;
2140 		}
2141 	}
2142 	mtx_unlock_spin(&icu_lock);
2143 	return (vector);
2144 }
2145 
2146 void
lapic_ipi_free(int vector)2147 lapic_ipi_free(int vector)
2148 {
2149 	struct gate_descriptor *ip;
2150 	long func __diagused;
2151 
2152 	KASSERT(vector >= IPI_DYN_FIRST && vector <= IPI_DYN_LAST,
2153 	    ("%s: invalid vector %d", __func__, vector));
2154 
2155 	mtx_lock_spin(&icu_lock);
2156 	ip = &idt[vector];
2157 	func = (ip->gd_hioffset << 16) | ip->gd_looffset;
2158 #ifdef __i386__
2159 	func -= setidt_disp;
2160 #endif
2161 	KASSERT(func != (uintptr_t)&IDTVEC(rsvd) &&
2162 	    func != (uintptr_t)&IDTVEC(rsvd_pti),
2163 	    ("invalid idtfunc %#lx", func));
2164 	setidt(vector, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd), SDT_APIC,
2165 	    SEL_KPL, GSEL_APIC);
2166 	mtx_unlock_spin(&icu_lock);
2167 }
2168