xref: /freebsd/sys/x86/x86/local_apic.c (revision 4f2465260f035fa0095e73b34a74851ef2efaa83)
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 
39 #include "opt_ddb.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/asan.h>
44 #include <sys/bus.h>
45 #include <sys/kernel.h>
46 #include <sys/lock.h>
47 #include <sys/malloc.h>
48 #include <sys/msan.h>
49 #include <sys/mutex.h>
50 #include <sys/pcpu.h>
51 #include <sys/proc.h>
52 #include <sys/refcount.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/atomic.h>
64 #include <machine/clock.h>
65 #include <machine/cpufunc.h>
66 #include <machine/cputypes.h>
67 #include <machine/fpu.h>
68 #include <machine/frame.h>
69 #include <machine/intr_machdep.h>
70 #include <x86/apicvar.h>
71 #include <x86/mca.h>
72 #include <machine/md_var.h>
73 #include <machine/smp.h>
74 #include <machine/specialreg.h>
75 #include <x86/init.h>
76 #include <x86/kvm.h>
77 #include <contrib/xen/arch-x86/cpuid.h>
78 #include <x86/bhyve.h>
79 #include <dev/hyperv/vmbus/x86/hyperv_reg.h>
80 
81 #ifdef DDB
82 #include <sys/interrupt.h>
83 #include <ddb/ddb.h>
84 #endif
85 
86 #ifdef __amd64__
87 #define	SDT_APIC	SDT_SYSIGT
88 #define	GSEL_APIC	0
89 #else
90 #define	SDT_APIC	SDT_SYS386IGT
91 #define	GSEL_APIC	GSEL(GCODE_SEL, SEL_KPL)
92 #endif
93 
94 static MALLOC_DEFINE(M_LAPIC, "local_apic", "Local APIC items");
95 
96 /* Sanity checks on IDT vectors. */
97 CTASSERT(APIC_IO_INTS + APIC_NUM_IOINTS == APIC_TIMER_INT);
98 CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS);
99 CTASSERT(APIC_LOCAL_INTS == 240);
100 CTASSERT(IPI_STOP < APIC_SPURIOUS_INT);
101 
102 /*
103  * I/O interrupts use non-negative IRQ values.  These values are used
104  * to mark unused IDT entries or IDT entries reserved for a non-I/O
105  * interrupt.
106  */
107 #define	IRQ_FREE	-1
108 #define	IRQ_TIMER	-2
109 #define	IRQ_SYSCALL	-3
110 #define	IRQ_DTRACE_RET	-4
111 #define	IRQ_EVTCHN	-5
112 
113 enum lat_timer_mode {
114 	LAT_MODE_UNDEF =	0,
115 	LAT_MODE_PERIODIC =	1,
116 	LAT_MODE_ONESHOT =	2,
117 	LAT_MODE_DEADLINE =	3,
118 };
119 
120 /*
121  * Support for local APICs.  Local APICs manage interrupts on each
122  * individual processor as opposed to I/O APICs which receive interrupts
123  * from I/O devices and then forward them on to the local APICs.
124  *
125  * Local APICs can also send interrupts to each other thus providing the
126  * mechanism for IPIs.
127  */
128 
129 struct lvt {
130 	u_int lvt_edgetrigger:1;
131 	u_int lvt_activehi:1;
132 	u_int lvt_masked:1;
133 	u_int lvt_active:1;
134 	u_int lvt_mode:16;
135 	u_int lvt_vector:8;
136 	u_int lvt_reg;
137 	const char *lvt_desc;
138 };
139 
140 struct lapic {
141 	struct lvt la_lvts[APIC_LVT_MAX + 1];
142 	struct lvt la_elvts[APIC_ELVT_MAX + 1];
143 	u_int la_id:8;
144 	u_int la_cluster:4;
145 	u_int la_cluster_id:2;
146 	u_int la_present:1;
147 	u_long *la_timer_count;
148 	uint64_t la_timer_period;
149 	enum lat_timer_mode la_timer_mode;
150 	uint32_t lvt_timer_base;
151 	uint32_t lvt_timer_last;
152 	/* Include IDT_SYSCALL to make indexing easier. */
153 	int la_ioint_irqs[APIC_NUM_IOINTS + 1];
154 } static *lapics;
155 
156 /* Global defaults for local APIC LVT entries. */
157 static struct lvt lvts[] = {
158 	/* LINT0: masked ExtINT */
159 	[APIC_LVT_LINT0] = {
160 		.lvt_edgetrigger = 1,
161 		.lvt_activehi = 1,
162 		.lvt_masked = 1,
163 		.lvt_active = 1,
164 		.lvt_mode = APIC_LVT_DM_EXTINT,
165 		.lvt_vector = 0,
166 		.lvt_reg = LAPIC_LVT_LINT0,
167 		.lvt_desc = "LINT0",
168 	},
169 	/* LINT1: NMI */
170 	[APIC_LVT_LINT1] = {
171 		.lvt_edgetrigger = 1,
172 		.lvt_activehi = 1,
173 		.lvt_masked = 0,
174 		.lvt_active = 1,
175 		.lvt_mode = APIC_LVT_DM_NMI,
176 		.lvt_vector = 0,
177 		.lvt_reg = LAPIC_LVT_LINT1,
178 		.lvt_desc = "LINT1",
179 	},
180 	[APIC_LVT_TIMER] = {
181 		.lvt_edgetrigger = 1,
182 		.lvt_activehi = 1,
183 		.lvt_masked = 1,
184 		.lvt_active = 1,
185 		.lvt_mode = APIC_LVT_DM_FIXED,
186 		.lvt_vector = APIC_TIMER_INT,
187 		.lvt_reg = LAPIC_LVT_TIMER,
188 		.lvt_desc = "TIMER",
189 	},
190 	[APIC_LVT_ERROR] = {
191 		.lvt_edgetrigger = 1,
192 		.lvt_activehi = 1,
193 		.lvt_masked = 0,
194 		.lvt_active = 1,
195 		.lvt_mode = APIC_LVT_DM_FIXED,
196 		.lvt_vector = APIC_ERROR_INT,
197 		.lvt_reg = LAPIC_LVT_ERROR,
198 		.lvt_desc = "ERROR",
199 	},
200 	[APIC_LVT_PMC] = {
201 		.lvt_edgetrigger = 1,
202 		.lvt_activehi = 1,
203 		.lvt_masked = 1,
204 		.lvt_active = 1,
205 		.lvt_mode = APIC_LVT_DM_NMI,
206 		.lvt_vector = 0,
207 		.lvt_reg = LAPIC_LVT_PCINT,
208 		.lvt_desc = "PMC",
209 	},
210 	[APIC_LVT_THERMAL] = {
211 		.lvt_edgetrigger = 1,
212 		.lvt_activehi = 1,
213 		.lvt_masked = 1,
214 		.lvt_active = 1,
215 		.lvt_mode = APIC_LVT_DM_FIXED,
216 		.lvt_vector = APIC_THERMAL_INT,
217 		.lvt_reg = LAPIC_LVT_THERMAL,
218 		.lvt_desc = "THERM",
219 	},
220 	[APIC_LVT_CMCI] = {
221 		.lvt_edgetrigger = 1,
222 		.lvt_activehi = 1,
223 		.lvt_masked = 1,
224 		.lvt_active = 1,
225 		.lvt_mode = APIC_LVT_DM_FIXED,
226 		.lvt_vector = APIC_CMC_INT,
227 		.lvt_reg = LAPIC_LVT_CMCI,
228 		.lvt_desc = "CMCI",
229 	},
230 };
231 
232 /* Global defaults for AMD local APIC ELVT entries. */
233 static struct lvt elvts[] = {
234 	[APIC_ELVT_IBS] = {
235 		.lvt_edgetrigger = 1,
236 		.lvt_activehi = 1,
237 		.lvt_masked = 1,
238 		.lvt_active = 1,
239 		.lvt_mode = APIC_LVT_DM_NMI,
240 		.lvt_vector = 0,
241 		.lvt_reg = LAPIC_EXT_LVT0,
242 		.lvt_desc = "IBS",
243 	},
244 	[APIC_ELVT_MCA] = {
245 		.lvt_edgetrigger = 1,
246 		.lvt_activehi = 1,
247 		.lvt_masked = 1,
248 		.lvt_active = 0,
249 		.lvt_mode = APIC_LVT_DM_FIXED,
250 		.lvt_vector = APIC_CMC_INT,
251 		.lvt_reg = LAPIC_EXT_LVT1,
252 		.lvt_desc = "MCA",
253 	},
254 	[APIC_ELVT_DEI] = {
255 		.lvt_edgetrigger = 1,
256 		.lvt_activehi = 1,
257 		.lvt_masked = 1,
258 		.lvt_active = 0,
259 		.lvt_mode = APIC_LVT_DM_FIXED,
260 		.lvt_vector = 0,
261 		.lvt_reg = LAPIC_EXT_LVT2,
262 		.lvt_desc = "ELVT2",
263 	},
264 	[APIC_ELVT_SBI] = {
265 		.lvt_edgetrigger = 1,
266 		.lvt_activehi = 1,
267 		.lvt_masked = 1,
268 		.lvt_active = 0,
269 		.lvt_mode = APIC_LVT_DM_FIXED,
270 		.lvt_vector = 0,
271 		.lvt_reg = LAPIC_EXT_LVT3,
272 		.lvt_desc = "ELVT3",
273 	},
274 };
275 
276 static inthand_t *ioint_handlers[] = {
277 	NULL,			/* 0 - 31 */
278 	IDTVEC(apic_isr1),	/* 32 - 63 */
279 	IDTVEC(apic_isr2),	/* 64 - 95 */
280 	IDTVEC(apic_isr3),	/* 96 - 127 */
281 	IDTVEC(apic_isr4),	/* 128 - 159 */
282 	IDTVEC(apic_isr5),	/* 160 - 191 */
283 	IDTVEC(apic_isr6),	/* 192 - 223 */
284 	IDTVEC(apic_isr7),	/* 224 - 255 */
285 };
286 
287 static inthand_t *ioint_pti_handlers[] = {
288 	NULL,			/* 0 - 31 */
289 	IDTVEC(apic_isr1_pti),	/* 32 - 63 */
290 	IDTVEC(apic_isr2_pti),	/* 64 - 95 */
291 	IDTVEC(apic_isr3_pti),	/* 96 - 127 */
292 	IDTVEC(apic_isr4_pti),	/* 128 - 159 */
293 	IDTVEC(apic_isr5_pti),	/* 160 - 191 */
294 	IDTVEC(apic_isr6_pti),	/* 192 - 223 */
295 	IDTVEC(apic_isr7_pti),	/* 224 - 255 */
296 };
297 
298 static u_int32_t lapic_timer_divisors[] = {
299 	APIC_TDCR_1, APIC_TDCR_2, APIC_TDCR_4, APIC_TDCR_8, APIC_TDCR_16,
300 	APIC_TDCR_32, APIC_TDCR_64, APIC_TDCR_128
301 };
302 
303 extern inthand_t IDTVEC(rsvd_pti), IDTVEC(rsvd);
304 
305 volatile char *lapic_map;
306 vm_paddr_t lapic_paddr = DEFAULT_APIC_BASE;
307 int x2apic_mode;
308 int lapic_eoi_suppression;
309 static int lapic_timer_tsc_deadline;
310 static u_long lapic_timer_divisor, count_freq;
311 static struct eventtimer lapic_et;
312 #ifdef SMP
313 static uint64_t lapic_ipi_wait_mult;
314 static int __read_mostly lapic_ds_idle_timeout = 1000000;
315 #endif
316 unsigned int max_apic_id;
317 static lapic_thermal_handler_t *lapic_thermal_function;
318 static void *lapic_thermal_function_arg;
319 static int pcint_refcnt = 0;
320 
321 SYSCTL_NODE(_hw, OID_AUTO, apic, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
322     "APIC options");
323 SYSCTL_INT(_hw_apic, OID_AUTO, x2apic_mode, CTLFLAG_RD, &x2apic_mode, 0, "");
324 SYSCTL_INT(_hw_apic, OID_AUTO, eoi_suppression, CTLFLAG_RD,
325     &lapic_eoi_suppression, 0, "");
326 SYSCTL_INT(_hw_apic, OID_AUTO, timer_tsc_deadline, CTLFLAG_RD,
327     &lapic_timer_tsc_deadline, 0, "");
328 #ifdef SMP
329 SYSCTL_INT(_hw_apic, OID_AUTO, ds_idle_timeout, CTLFLAG_RWTUN,
330     &lapic_ds_idle_timeout, 0,
331     "timeout (in us) for APIC Delivery Status to become Idle (xAPIC only)");
332 #endif
333 
334 static void lapic_calibrate_initcount(struct lapic *la);
335 
336 /*
337  * Use __nosanitizethread to exempt the LAPIC I/O accessors from KCSan
338  * instrumentation.  Otherwise, if x2APIC is not available, use of the global
339  * lapic_map will generate a KCSan false positive.  While the mapping is
340  * shared among all CPUs, the physical access will always take place on the
341  * local CPU's APIC, so there isn't in fact a race here.  Furthermore, the
342  * KCSan warning printf can cause a panic if issued during LAPIC access,
343  * due to attempted recursive use of event timer resources.
344  */
345 
346 static uint32_t __nosanitizethread
lapic_read32(enum LAPIC_REGISTERS reg)347 lapic_read32(enum LAPIC_REGISTERS reg)
348 {
349 	uint32_t res;
350 
351 	if (x2apic_mode) {
352 		res = rdmsr32(MSR_APIC_000 + reg);
353 	} else {
354 		res = *(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL);
355 	}
356 	return (res);
357 }
358 
359 static void __nosanitizethread
lapic_write32(enum LAPIC_REGISTERS reg,uint32_t val)360 lapic_write32(enum LAPIC_REGISTERS reg, uint32_t val)
361 {
362 
363 	if (x2apic_mode) {
364 		mfence();
365 		lfence();
366 		wrmsr(MSR_APIC_000 + reg, val);
367 	} else {
368 		*(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL) = val;
369 	}
370 }
371 
372 static void __nosanitizethread
lapic_write32_nofence(enum LAPIC_REGISTERS reg,uint32_t val)373 lapic_write32_nofence(enum LAPIC_REGISTERS reg, uint32_t val)
374 {
375 
376 	if (x2apic_mode) {
377 		wrmsr(MSR_APIC_000 + reg, val);
378 	} else {
379 		*(volatile uint32_t *)(lapic_map + reg * LAPIC_MEM_MUL) = val;
380 	}
381 }
382 
383 static inline uint32_t __pure2
lapic_version(void)384 lapic_version(void)
385 {
386 	return (lapic_read32(LAPIC_VERSION));
387 }
388 
389 /*
390  * Calculate the max index of the present LVT entry from the value of
391  * the LAPIC version register.
392  */
393 static inline int __pure2
lapic_version_maxlvt(uint32_t version)394 lapic_version_maxlvt(uint32_t version)
395 {
396 	return ((version & APIC_VER_MAXLVT) >> MAXLVTSHIFT);
397 }
398 
399 static inline int __pure2
lapic_maxlvt(void)400 lapic_maxlvt(void)
401 {
402 	return (lapic_version_maxlvt(lapic_version()));
403 }
404 
405 #ifdef SMP
406 static uint64_t
lapic_read_icr_lo(void)407 lapic_read_icr_lo(void)
408 {
409 
410 	return (lapic_read32(LAPIC_ICR_LO));
411 }
412 
413 static void
lapic_write_icr(uint32_t vhi,uint32_t vlo)414 lapic_write_icr(uint32_t vhi, uint32_t vlo)
415 {
416 	register_t saveintr;
417 	uint64_t v;
418 
419 	if (x2apic_mode) {
420 		v = ((uint64_t)vhi << 32) | vlo;
421 		mfence();
422 		wrmsr(MSR_APIC_000 + LAPIC_ICR_LO, v);
423 	} else {
424 		saveintr = intr_disable();
425 		lapic_write32(LAPIC_ICR_HI, vhi);
426 		lapic_write32(LAPIC_ICR_LO, vlo);
427 		intr_restore(saveintr);
428 	}
429 }
430 
431 static void
lapic_write_icr_lo(uint32_t vlo)432 lapic_write_icr_lo(uint32_t vlo)
433 {
434 
435 	if (x2apic_mode) {
436 		mfence();
437 		wrmsr(MSR_APIC_000 + LAPIC_ICR_LO, vlo);
438 	} else {
439 		lapic_write32(LAPIC_ICR_LO, vlo);
440 	}
441 }
442 
443 static void
lapic_write_self_ipi(uint32_t vector)444 lapic_write_self_ipi(uint32_t vector)
445 {
446 
447 	KASSERT(x2apic_mode, ("SELF IPI write in xAPIC mode"));
448 	wrmsr(MSR_APIC_000 + LAPIC_SELF_IPI, vector);
449 }
450 #endif /* SMP */
451 
452 static void
lapic_enable_x2apic(void)453 lapic_enable_x2apic(void)
454 {
455 	uint64_t apic_base;
456 
457 	apic_base = rdmsr(MSR_APICBASE);
458 	apic_base |= APICBASE_X2APIC | APICBASE_ENABLED;
459 	wrmsr(MSR_APICBASE, apic_base);
460 }
461 
462 bool
lapic_is_x2apic(void)463 lapic_is_x2apic(void)
464 {
465 	uint64_t apic_base;
466 
467 	apic_base = rdmsr(MSR_APICBASE);
468 	return ((apic_base & (APICBASE_X2APIC | APICBASE_ENABLED)) ==
469 	    (APICBASE_X2APIC | APICBASE_ENABLED));
470 }
471 
472 static void	lapic_early_mask_vecs(void);
473 static void	lapic_enable(void);
474 static void	lapic_resume(struct pic *pic, bool suspend_cancelled);
475 static void	lapic_timer_oneshot(struct lapic *);
476 static void	lapic_timer_oneshot_nointr(struct lapic *, uint32_t);
477 static void	lapic_timer_periodic(struct lapic *);
478 static void	lapic_timer_deadline(struct lapic *);
479 static void	lapic_timer_stop(struct lapic *);
480 static void	lapic_timer_set_divisor(u_int divisor);
481 static uint32_t	lvt_mode(struct lapic *la, u_int pin, uint32_t value);
482 static int	lapic_et_start(struct eventtimer *et,
483 		    sbintime_t first, sbintime_t period);
484 static int	lapic_et_stop(struct eventtimer *et);
485 static u_int	apic_idt_to_irq(u_int apic_id, u_int vector);
486 static void	lapic_set_tpr(u_int vector);
487 
488 struct pic lapic_pic = { .pic_resume = lapic_resume };
489 
490 static uint32_t
lvt_mode_impl(struct lapic * la,struct lvt * lvt,u_int pin,uint32_t value)491 lvt_mode_impl(struct lapic *la, struct lvt *lvt, u_int pin, uint32_t value)
492 {
493 
494 	value &= ~(APIC_LVT_M | APIC_LVT_TM | APIC_LVT_IIPP | APIC_LVT_DM |
495 	    APIC_LVT_VECTOR);
496 	if (lvt->lvt_edgetrigger == 0)
497 		value |= APIC_LVT_TM;
498 	if (lvt->lvt_activehi == 0)
499 		value |= APIC_LVT_IIPP_INTALO;
500 	if (lvt->lvt_masked)
501 		value |= APIC_LVT_M;
502 	value |= lvt->lvt_mode;
503 	switch (lvt->lvt_mode) {
504 	case APIC_LVT_DM_NMI:
505 	case APIC_LVT_DM_SMI:
506 	case APIC_LVT_DM_INIT:
507 	case APIC_LVT_DM_EXTINT:
508 		if (!lvt->lvt_edgetrigger) {
509 			if (bootverbose) {
510 				printf(
511 				    "lapic%u: Forcing LINT%u to edge trigger\n",
512 				    la->la_id, pin);
513 			}
514 			value &= ~APIC_LVT_TM;
515 		}
516 		/* Use a vector of 0. */
517 		break;
518 	case APIC_LVT_DM_FIXED:
519 		value |= lvt->lvt_vector;
520 		break;
521 	default:
522 		panic("bad APIC LVT delivery mode: %#x\n", value);
523 	}
524 	return (value);
525 }
526 
527 static uint32_t
lvt_mode(struct lapic * la,u_int pin,uint32_t value)528 lvt_mode(struct lapic *la, u_int pin, uint32_t value)
529 {
530 	struct lvt *lvt;
531 
532 	KASSERT(pin <= APIC_LVT_MAX,
533 	    ("%s: pin %u out of range", __func__, pin));
534 	if (la->la_lvts[pin].lvt_active)
535 		lvt = &la->la_lvts[pin];
536 	else
537 		lvt = &lvts[pin];
538 
539 	return (lvt_mode_impl(la, lvt, pin, value));
540 }
541 
542 static uint32_t
elvt_mode(struct lapic * la,u_int idx,uint32_t value)543 elvt_mode(struct lapic *la, u_int idx, uint32_t value)
544 {
545 	struct lvt *elvt;
546 
547 	KASSERT(idx <= APIC_ELVT_MAX,
548 	    ("%s: idx %u out of range", __func__, idx));
549 
550 	if (la->la_elvts[idx].lvt_active)
551 	    elvt = &la->la_elvts[idx];
552 	else
553 	    elvt = &elvts[idx];
554 	KASSERT(elvt->lvt_active, ("%s: ELVT%u is not active", __func__, idx));
555 	KASSERT(elvt->lvt_edgetrigger,
556 	    ("%s: ELVT%u is not edge triggered", __func__, idx));
557 	KASSERT(elvt->lvt_activehi,
558 	    ("%s: ELVT%u is not active high", __func__, idx));
559 	return (lvt_mode_impl(la, elvt, idx, value));
560 }
561 
562 /*
563  * Map the local APIC and setup necessary interrupt vectors.
564  */
565 void
lapic_init(vm_paddr_t addr)566 lapic_init(vm_paddr_t addr)
567 {
568 #ifdef SMP
569 	uint64_t r, r1, r2, rx;
570 #endif
571 	uint32_t ver;
572 	int i;
573 	bool arat;
574 
575 	TSENTER();
576 
577 	/*
578 	 * Enable x2APIC mode if possible. Map the local APIC
579 	 * registers page.
580 	 *
581 	 * Keep the LAPIC registers page mapped uncached for x2APIC
582 	 * mode too, to have direct map page attribute set to
583 	 * uncached.  This is needed to work around CPU errata present
584 	 * on all Intel processors.
585 	 */
586 	KASSERT(trunc_page(addr) == addr,
587 	    ("local APIC not aligned on a page boundary"));
588 	lapic_paddr = addr;
589 	lapic_map = pmap_mapdev(addr, PAGE_SIZE);
590 	if (x2apic_mode) {
591 		lapic_enable_x2apic();
592 		lapic_map = NULL;
593 	}
594 
595 	/* Setup the spurious interrupt handler. */
596 	setidt(APIC_SPURIOUS_INT, IDTVEC(spuriousint), SDT_APIC, SEL_KPL,
597 	    GSEL_APIC);
598 
599 	/* Perform basic initialization of the BSP's local APIC. */
600 	lapic_enable();
601 	lapic_early_mask_vecs();
602 
603 	/* Set BSP's per-CPU local APIC ID. */
604 	PCPU_SET(apic_id, lapic_id());
605 
606 	/* Local APIC timer interrupt. */
607 	setidt(APIC_TIMER_INT, pti ? IDTVEC(timerint_pti) : IDTVEC(timerint),
608 	    SDT_APIC, SEL_KPL, GSEL_APIC);
609 
610 	/* Local APIC error interrupt. */
611 	setidt(APIC_ERROR_INT, pti ? IDTVEC(errorint_pti) : IDTVEC(errorint),
612 	    SDT_APIC, SEL_KPL, GSEL_APIC);
613 
614 	/* Thermal interrupt */
615 	setidt(APIC_THERMAL_INT, pti ? IDTVEC(thermalint_pti) : IDTVEC(thermalint),
616 	    SDT_APIC, SEL_KPL, GSEL_APIC);
617 
618 	/* Local APIC CMCI. */
619 	setidt(APIC_CMC_INT, pti ? IDTVEC(cmcint_pti) : IDTVEC(cmcint),
620 	    SDT_APIC, SEL_KPL, GSEL_APIC);
621 
622 	if ((resource_int_value("apic", 0, "clock", &i) != 0 || i != 0)) {
623 		/* Set if APIC timer runs in C3. */
624 		arat = (cpu_power_eax & CPUTPM1_ARAT);
625 
626 		bzero(&lapic_et, sizeof(lapic_et));
627 		lapic_et.et_name = "LAPIC";
628 		lapic_et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT |
629 		    ET_FLAGS_PERCPU;
630 		lapic_et.et_quality = 600;
631 		if (!arat) {
632 			lapic_et.et_flags |= ET_FLAGS_C3STOP;
633 			lapic_et.et_quality = 100;
634 		}
635 		if ((cpu_feature & CPUID_TSC) != 0 &&
636 		    (cpu_feature2 & CPUID2_TSCDLT) != 0 &&
637 		    tsc_is_invariant && tsc_freq != 0) {
638 			lapic_timer_tsc_deadline = 1;
639 			TUNABLE_INT_FETCH("hw.apic.timer_tsc_deadline",
640 			    &lapic_timer_tsc_deadline);
641 		}
642 
643 		lapic_et.et_frequency = 0;
644 		/* We don't know frequency yet, so trying to guess. */
645 		lapic_et.et_min_period = 0x00001000LL;
646 		lapic_et.et_max_period = SBT_1S;
647 		lapic_et.et_start = lapic_et_start;
648 		lapic_et.et_stop = lapic_et_stop;
649 		lapic_et.et_priv = NULL;
650 		et_register(&lapic_et);
651 	}
652 
653 	/*
654 	 * Set lapic_eoi_suppression after lapic_enable(), to not
655 	 * enable suppression in the hardware prematurely.  Note that
656 	 * we by default enable suppression even when system only has
657 	 * one IO-APIC, since EOI is broadcasted to all APIC agents,
658 	 * including CPUs, otherwise.
659 	 *
660 	 * It seems that at least some KVM versions report
661 	 * EOI_SUPPRESSION bit, but auto-EOI does not work.
662 	 */
663 	ver = lapic_version();
664 	if ((ver & APIC_VER_EOI_SUPPRESSION) != 0) {
665 		lapic_eoi_suppression = 1;
666 		if (vm_guest == VM_GUEST_KVM) {
667 			if (bootverbose)
668 				printf(
669 		       "KVM -- disabling lapic eoi suppression\n");
670 			lapic_eoi_suppression = 0;
671 		}
672 		TUNABLE_INT_FETCH("hw.apic.eoi_suppression",
673 		    &lapic_eoi_suppression);
674 	}
675 
676 #ifdef SMP
677 #define	LOOPS	1000
678 	/*
679 	 * Calibrate the busy loop waiting for IPI ack in xAPIC mode.
680 	 * lapic_ipi_wait_mult contains the number of iterations which
681 	 * approximately delay execution for 1 microsecond (the
682 	 * argument to lapic_ipi_wait() is in microseconds).
683 	 *
684 	 * We assume that TSC is present and already measured.
685 	 * Possible TSC frequency jumps are irrelevant to the
686 	 * calibration loop below, the CPU clock management code is
687 	 * not yet started, and we do not enter sleep states.
688 	 */
689 	KASSERT((cpu_feature & CPUID_TSC) != 0 && tsc_freq != 0,
690 	    ("TSC not initialized"));
691 	if (!x2apic_mode) {
692 		r = rdtsc();
693 		for (rx = 0; rx < LOOPS; rx++) {
694 			(void)lapic_read_icr_lo();
695 			ia32_pause();
696 		}
697 		r = rdtsc() - r;
698 		r1 = tsc_freq * LOOPS;
699 		r2 = r * 1000000;
700 		lapic_ipi_wait_mult = r1 >= r2 ? r1 / r2 : 1;
701 		if (bootverbose) {
702 			printf("LAPIC: ipi_wait() us multiplier %ju (r %ju "
703 			    "tsc %ju)\n", (uintmax_t)lapic_ipi_wait_mult,
704 			    (uintmax_t)r, (uintmax_t)tsc_freq);
705 		}
706 	}
707 #undef LOOPS
708 #endif /* SMP */
709 
710 	TSEXIT();
711 }
712 
713 /*
714  * Create a local APIC instance.
715  */
716 void
lapic_create(u_int apic_id,int boot_cpu)717 lapic_create(u_int apic_id, int boot_cpu)
718 {
719 	int i;
720 
721 	if (apic_id > max_apic_id) {
722 		printf("APIC: Ignoring local APIC with ID %d\n", apic_id);
723 		if (boot_cpu)
724 			panic("Can't ignore BSP");
725 		return;
726 	}
727 	KASSERT(!lapics[apic_id].la_present, ("duplicate local APIC %u",
728 	    apic_id));
729 
730 	/*
731 	 * Assume no local LVT overrides and a cluster of 0 and
732 	 * intra-cluster ID of 0.
733 	 */
734 	lapics[apic_id].la_present = 1;
735 	lapics[apic_id].la_id = apic_id;
736 	for (i = 0; i <= APIC_LVT_MAX; i++) {
737 		lapics[apic_id].la_lvts[i] = lvts[i];
738 		lapics[apic_id].la_lvts[i].lvt_active = 0;
739 	}
740 	for (i = 0; i <= APIC_ELVT_MAX; i++) {
741 		lapics[apic_id].la_elvts[i] = elvts[i];
742 		lapics[apic_id].la_elvts[i].lvt_active = 0;
743 	}
744 	for (i = 0; i <= APIC_NUM_IOINTS; i++)
745 	    lapics[apic_id].la_ioint_irqs[i] = IRQ_FREE;
746 	lapics[apic_id].la_ioint_irqs[IDT_SYSCALL - APIC_IO_INTS] = IRQ_SYSCALL;
747 	lapics[apic_id].la_ioint_irqs[APIC_TIMER_INT - APIC_IO_INTS] =
748 	    IRQ_TIMER;
749 #ifdef KDTRACE_HOOKS
750 	lapics[apic_id].la_ioint_irqs[IDT_DTRACE_RET - APIC_IO_INTS] =
751 	    IRQ_DTRACE_RET;
752 #endif
753 #ifdef XENHVM
754 	lapics[apic_id].la_ioint_irqs[IDT_EVTCHN - APIC_IO_INTS] = IRQ_EVTCHN;
755 #endif
756 
757 #ifdef SMP
758 	cpu_add(apic_id, boot_cpu);
759 #endif
760 }
761 
762 static inline uint32_t
amd_read_ext_features(void)763 amd_read_ext_features(void)
764 {
765 	uint32_t version;
766 
767 	if (cpu_vendor_id != CPU_VENDOR_AMD &&
768 	    cpu_vendor_id != CPU_VENDOR_HYGON)
769 		return (0);
770 	version = lapic_version();
771 	if ((version & APIC_VER_AMD_EXT_SPACE) != 0)
772 		return (lapic_read32(LAPIC_EXT_FEATURES));
773 	else
774 		return (0);
775 }
776 
777 static inline uint32_t
amd_read_elvt_count(void)778 amd_read_elvt_count(void)
779 {
780 	uint32_t extf;
781 	uint32_t count;
782 
783 	extf = amd_read_ext_features();
784 	count = (extf & APIC_EXTF_ELVT_MASK) >> APIC_EXTF_ELVT_SHIFT;
785 	count = min(count, APIC_ELVT_MAX + 1);
786 	return (count);
787 }
788 
789 /*
790  * Dump contents of local APIC registers
791  */
792 void
lapic_dump(const char * str)793 lapic_dump(const char* str)
794 {
795 	const uint32_t version = lapic_version();
796 	const int maxlvt = lapic_version_maxlvt(version);
797 	uint32_t extf;
798 	int elvt_count;
799 	int i;
800 
801 	printf("cpu%d %s:\n", PCPU_GET(cpuid), str);
802 	printf("     ID: 0x%08x   VER: 0x%08x LDR: 0x%08x DFR: 0x%08x",
803 	    lapic_read32(LAPIC_ID), version,
804 	    lapic_read32(LAPIC_LDR), x2apic_mode ? 0 : lapic_read32(LAPIC_DFR));
805 	if ((cpu_feature2 & CPUID2_X2APIC) != 0)
806 		printf(" x2APIC: %d", x2apic_mode);
807 	printf("\n  lint0: 0x%08x lint1: 0x%08x TPR: 0x%08x SVR: 0x%08x\n",
808 	    lapic_read32(LAPIC_LVT_LINT0), lapic_read32(LAPIC_LVT_LINT1),
809 	    lapic_read32(LAPIC_TPR), lapic_read32(LAPIC_SVR));
810 	printf("  timer: 0x%08x err: 0x%08x", lapic_read32(LAPIC_LVT_TIMER),
811 	    lapic_read32(LAPIC_LVT_ERROR));
812 	if (maxlvt >= APIC_LVT_THERMAL)
813 		printf(" therm: 0x%08x", lapic_read32(LAPIC_LVT_THERMAL));
814 	if (maxlvt >= APIC_LVT_PMC)
815 		printf(" pmc: 0x%08x", lapic_read32(LAPIC_LVT_PCINT));
816 	printf("\n");
817 	if (maxlvt >= APIC_LVT_CMCI)
818 		printf("   cmci: 0x%08x\n", lapic_read32(LAPIC_LVT_CMCI));
819 	extf = amd_read_ext_features();
820 	if (extf != 0) {
821 		printf("   AMD ext features: 0x%08x", extf);
822 		elvt_count = amd_read_elvt_count();
823 		for (i = 0; i < elvt_count; i++)
824 			printf("%s elvt%d: 0x%08x", (i % 4) ? "" : "\n ", i,
825 			    lapic_read32(LAPIC_EXT_LVT0 + i));
826 		printf("\n");
827 	}
828 }
829 
830 void
lapic_xapic_mode(void)831 lapic_xapic_mode(void)
832 {
833 	register_t saveintr;
834 
835 	saveintr = intr_disable();
836 	if (x2apic_mode)
837 		lapic_enable_x2apic();
838 	intr_restore(saveintr);
839 }
840 
841 static void
lapic_early_mask_vec(const struct lvt * l)842 lapic_early_mask_vec(const struct lvt *l)
843 {
844 	uint32_t v;
845 
846 	if (l->lvt_masked != 0) {
847 		v = lapic_read32(l->lvt_reg);
848 		v |= APIC_LVT_M;
849 		lapic_write32(l->lvt_reg, v);
850 	}
851 }
852 
853 /* Done on BSP only */
854 static void
lapic_early_mask_vecs(void)855 lapic_early_mask_vecs(void)
856 {
857 	int elvt_count, lvts_count, i;
858 
859 	lvts_count = min(nitems(lvts), lapic_maxlvt() + 1);
860 	for (i = 0; i < lvts_count; i++)
861 		lapic_early_mask_vec(&lvts[i]);
862 
863 	elvt_count = amd_read_elvt_count();
864 	for (i = 0; i < elvt_count; i++)
865 		lapic_early_mask_vec(&elvts[i]);
866 }
867 
868 void
lapic_setup(int boot)869 lapic_setup(int boot)
870 {
871 	const uint32_t version = lapic_version();
872 	const uint32_t maxlvt = lapic_version_maxlvt(version);
873 	struct lapic *la;
874 	register_t saveintr;
875 	int elvt_count;
876 	int i;
877 
878 	saveintr = intr_disable();
879 
880 	la = &lapics[lapic_id()];
881 	KASSERT(la->la_present, ("missing APIC structure"));
882 
883 	/* Initialize the TPR to allow all interrupts. */
884 	lapic_set_tpr(0);
885 
886 	/* Setup spurious vector and enable the local APIC. */
887 	lapic_enable();
888 
889 	/* Program LINT[01] LVT entries. */
890 	lapic_write32(LAPIC_LVT_LINT0, lvt_mode(la, APIC_LVT_LINT0,
891 	    lapic_read32(LAPIC_LVT_LINT0)));
892 	lapic_write32(LAPIC_LVT_LINT1, lvt_mode(la, APIC_LVT_LINT1,
893 	    lapic_read32(LAPIC_LVT_LINT1)));
894 
895 	/* Program the PMC LVT entry if present. */
896 	if (maxlvt >= APIC_LVT_PMC) {
897 		lapic_write32(LAPIC_LVT_PCINT, lvt_mode(la, APIC_LVT_PMC,
898 		    LAPIC_LVT_PCINT));
899 	}
900 
901 	/*
902 	 * Program the timer LVT.  Calibration is deferred until it is certain
903 	 * that we have a reliable timecounter.
904 	 */
905 	la->lvt_timer_base = lvt_mode(la, APIC_LVT_TIMER,
906 	    lapic_read32(LAPIC_LVT_TIMER));
907 	la->lvt_timer_last = la->lvt_timer_base;
908 	lapic_write32(LAPIC_LVT_TIMER, la->lvt_timer_base);
909 
910 	if (boot)
911 		la->la_timer_mode = LAT_MODE_UNDEF;
912 	else if (la->la_timer_mode != LAT_MODE_UNDEF) {
913 		KASSERT(la->la_timer_period != 0, ("lapic%u: zero divisor",
914 		    lapic_id()));
915 		switch (la->la_timer_mode) {
916 		case LAT_MODE_PERIODIC:
917 			lapic_timer_set_divisor(lapic_timer_divisor);
918 			lapic_timer_periodic(la);
919 			break;
920 		case LAT_MODE_ONESHOT:
921 			lapic_timer_set_divisor(lapic_timer_divisor);
922 			lapic_timer_oneshot(la);
923 			break;
924 		case LAT_MODE_DEADLINE:
925 			lapic_timer_deadline(la);
926 			break;
927 		default:
928 			panic("corrupted la_timer_mode %p %d", la,
929 			    la->la_timer_mode);
930 		}
931 	}
932 
933 	/* Program error LVT and clear any existing errors. */
934 	lapic_write32(LAPIC_LVT_ERROR, lvt_mode(la, APIC_LVT_ERROR,
935 	    lapic_read32(LAPIC_LVT_ERROR)));
936 	lapic_write32(LAPIC_ESR, 0);
937 
938 	/* Thermal LVT */
939 	if (maxlvt >= APIC_LVT_THERMAL)
940 		lapic_write32(LAPIC_LVT_THERMAL, lvt_mode(la, APIC_LVT_THERMAL,
941 		    lapic_read32(LAPIC_LVT_THERMAL)));
942 
943 	/* Program the CMCI LVT entry if present. */
944 	if (maxlvt >= APIC_LVT_CMCI) {
945 		lapic_write32(LAPIC_LVT_CMCI, lvt_mode(la, APIC_LVT_CMCI,
946 		    lapic_read32(LAPIC_LVT_CMCI)));
947 	}
948 
949 	elvt_count = amd_read_elvt_count();
950 	for (i = 0; i < elvt_count; i++) {
951 		if (la->la_elvts[i].lvt_active)
952 			lapic_write32(LAPIC_EXT_LVT0 + i,
953 			    elvt_mode(la, i, lapic_read32(LAPIC_EXT_LVT0 + i)));
954 	}
955 
956 	intr_restore(saveintr);
957 }
958 
959 static void
lapic_intrcnt(void * dummy __unused)960 lapic_intrcnt(void *dummy __unused)
961 {
962 	struct pcpu *pc;
963 	struct lapic *la;
964 	char buf[MAXCOMLEN + 1];
965 
966 	/* If there are no APICs, skip this function. */
967 	if (lapics == NULL)
968 		return;
969 
970 	STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
971 		la = &lapics[pc->pc_apic_id];
972 		if (!la->la_present)
973 		    continue;
974 
975 		snprintf(buf, sizeof(buf), "cpu%d:timer", pc->pc_cpuid);
976 		intrcnt_add(buf, &la->la_timer_count);
977 	}
978 }
979 SYSINIT(lapic_intrcnt, SI_SUB_INTR, SI_ORDER_MIDDLE, lapic_intrcnt, NULL);
980 
981 void
lapic_reenable_pcint(void)982 lapic_reenable_pcint(void)
983 {
984 	uint32_t value;
985 
986 	if (refcount_load(&pcint_refcnt) == 0)
987 		return;
988 
989 	value = lapic_read32(LAPIC_LVT_PCINT);
990 	value &= ~APIC_LVT_M;
991 	lapic_write32(LAPIC_LVT_PCINT, value);
992 
993 	if ((amd_feature2 & AMDID2_IBS) != 0) {
994 		value = lapic_read32(LAPIC_EXT_LVT0);
995 		value &= ~APIC_LVT_M;
996 		lapic_write32(LAPIC_EXT_LVT0, value);
997 	}
998 }
999 
1000 static void
lapic_update_pcint(void * dummy)1001 lapic_update_pcint(void *dummy)
1002 {
1003 	struct lapic *la;
1004 
1005 	la = &lapics[lapic_id()];
1006 	lapic_write32(LAPIC_LVT_PCINT, lvt_mode(la, APIC_LVT_PMC,
1007 	    lapic_read32(LAPIC_LVT_PCINT)));
1008 
1009 	if ((amd_feature2 & AMDID2_IBS) != 0) {
1010 		lapic_write32(LAPIC_EXT_LVT0, elvt_mode(la, APIC_ELVT_IBS,
1011 		    lapic_read32(LAPIC_EXT_LVT0)));
1012 	}
1013 }
1014 
1015 void
lapic_calibrate_timer(void)1016 lapic_calibrate_timer(void)
1017 {
1018 	struct lapic *la;
1019 	register_t intr;
1020 
1021 #ifdef DEV_ATPIC
1022 	/* Fail if the local APIC is not present. */
1023 	if (!x2apic_mode && lapic_map == NULL)
1024 		return;
1025 #endif
1026 
1027 	intr = intr_disable();
1028 	la = &lapics[lapic_id()];
1029 
1030 	lapic_calibrate_initcount(la);
1031 
1032 	intr_restore(intr);
1033 
1034 	if (lapic_timer_tsc_deadline && bootverbose) {
1035 		printf("lapic: deadline tsc mode, Frequency %ju Hz\n",
1036 		    (uintmax_t)tsc_freq);
1037 	}
1038 }
1039 
1040 int
lapic_enable_pcint(void)1041 lapic_enable_pcint(void)
1042 {
1043 #ifdef DEV_ATPIC
1044 	/* Fail if the local APIC is not present. */
1045 	if (!x2apic_mode && lapic_map == NULL)
1046 		return (0);
1047 #endif
1048 
1049 	/* Fail if the PMC LVT is not present. */
1050 	if (lapic_maxlvt() < APIC_LVT_PMC)
1051 		return (0);
1052 	if (refcount_acquire(&pcint_refcnt) > 0)
1053 		return (1);
1054 	lvts[APIC_LVT_PMC].lvt_masked = 0;
1055 
1056 	if ((amd_feature2 & AMDID2_IBS) != 0)
1057 		elvts[APIC_ELVT_IBS].lvt_masked = 0;
1058 
1059 	MPASS(mp_ncpus == 1 || smp_started);
1060 	smp_rendezvous(NULL, lapic_update_pcint, NULL, NULL);
1061 	return (1);
1062 }
1063 
1064 void
lapic_disable_pcint(void)1065 lapic_disable_pcint(void)
1066 {
1067 #ifdef DEV_ATPIC
1068 	/* Fail if the local APIC is not present. */
1069 	if (!x2apic_mode && lapic_map == NULL)
1070 		return;
1071 #endif
1072 
1073 	/* Fail if the PMC LVT is not present. */
1074 	if (lapic_maxlvt() < APIC_LVT_PMC)
1075 		return;
1076 	if (!refcount_release(&pcint_refcnt))
1077 		return;
1078 	lvts[APIC_LVT_PMC].lvt_masked = 1;
1079 	elvts[APIC_ELVT_IBS].lvt_masked = 1;
1080 
1081 #ifdef SMP
1082 	/* The APs should always be started when hwpmc is unloaded. */
1083 	KASSERT(mp_ncpus == 1 || smp_started, ("hwpmc unloaded too early"));
1084 #endif
1085 	smp_rendezvous(NULL, lapic_update_pcint, NULL, NULL);
1086 }
1087 
1088 static int
lapic_calibrate_initcount_cpuid_vm(void)1089 lapic_calibrate_initcount_cpuid_vm(void)
1090 {
1091 	u_int regs[4];
1092 	uint64_t freq;
1093 
1094 	/* Get value from CPUID leaf if possible. */
1095 	if (vm_guest == VM_GUEST_NO)
1096 		return (false);
1097 	if (hv_high < 0x40000010)
1098 		return (false);
1099 	do_cpuid(0x40000010, regs);
1100 	freq = (uint64_t)(regs[1]) * 1000;
1101 
1102 	/* Pick timer divisor. */
1103 	lapic_timer_divisor = 2;
1104 	do {
1105 		if (freq / lapic_timer_divisor < APIC_TIMER_MAX_COUNT)
1106 			break;
1107 		lapic_timer_divisor <<= 1;
1108 	} while (lapic_timer_divisor <= 128);
1109 	if (lapic_timer_divisor > 128)
1110 		return (false);
1111 
1112 	/* Record divided frequency. */
1113 	count_freq = freq / lapic_timer_divisor;
1114 	return (count_freq != 0);
1115 }
1116 
1117 static uint64_t
cb_lapic_getcount(void)1118 cb_lapic_getcount(void)
1119 {
1120 
1121 	return (APIC_TIMER_MAX_COUNT - lapic_read32(LAPIC_CCR_TIMER));
1122 }
1123 
1124 static void
lapic_calibrate_initcount(struct lapic * la)1125 lapic_calibrate_initcount(struct lapic *la)
1126 {
1127 	uint64_t freq;
1128 
1129 	if (lapic_calibrate_initcount_cpuid_vm())
1130 		goto done;
1131 
1132 	/* Calibrate the APIC timer frequency. */
1133 	lapic_timer_set_divisor(2);
1134 	lapic_timer_oneshot_nointr(la, APIC_TIMER_MAX_COUNT);
1135 	fpu_kern_enter(curthread, NULL, FPU_KERN_NOCTX);
1136 	freq = clockcalib(cb_lapic_getcount, "lapic");
1137 	fpu_kern_leave(curthread, NULL);
1138 
1139 	/* Pick a different divisor if necessary. */
1140 	lapic_timer_divisor = 2;
1141 	do {
1142 		if (freq * 2 / lapic_timer_divisor < APIC_TIMER_MAX_COUNT)
1143 			break;
1144 		lapic_timer_divisor <<= 1;
1145 	} while (lapic_timer_divisor <= 128);
1146 	if (lapic_timer_divisor > 128)
1147 		panic("lapic: Divisor too big");
1148 	count_freq = freq * 2 / lapic_timer_divisor;
1149 done:
1150 	if (bootverbose) {
1151 		printf("lapic: Divisor %lu, Frequency %lu Hz\n",
1152 		    lapic_timer_divisor, count_freq);
1153 	}
1154 }
1155 
1156 static void
lapic_change_mode(struct eventtimer * et,struct lapic * la,enum lat_timer_mode newmode)1157 lapic_change_mode(struct eventtimer *et, struct lapic *la,
1158     enum lat_timer_mode newmode)
1159 {
1160 	if (la->la_timer_mode == newmode)
1161 		return;
1162 	switch (newmode) {
1163 	case LAT_MODE_PERIODIC:
1164 		lapic_timer_set_divisor(lapic_timer_divisor);
1165 		et->et_frequency = count_freq;
1166 		break;
1167 	case LAT_MODE_DEADLINE:
1168 		et->et_frequency = tsc_freq;
1169 		break;
1170 	case LAT_MODE_ONESHOT:
1171 		lapic_timer_set_divisor(lapic_timer_divisor);
1172 		et->et_frequency = count_freq;
1173 		break;
1174 	default:
1175 		panic("lapic_change_mode %d", newmode);
1176 	}
1177 	la->la_timer_mode = newmode;
1178 	et->et_min_period = (0x00000002LLU << 32) / et->et_frequency;
1179 	et->et_max_period = (0xfffffffeLLU << 32) / et->et_frequency;
1180 }
1181 
1182 static int
lapic_et_start(struct eventtimer * et,sbintime_t first,sbintime_t period)1183 lapic_et_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
1184 {
1185 	struct lapic *la;
1186 
1187 	la = &lapics[PCPU_GET(apic_id)];
1188 	if (period != 0) {
1189 		lapic_change_mode(et, la, LAT_MODE_PERIODIC);
1190 		la->la_timer_period = ((uint32_t)et->et_frequency * period) >>
1191 		    32;
1192 		lapic_timer_periodic(la);
1193 	} else if (lapic_timer_tsc_deadline) {
1194 		lapic_change_mode(et, la, LAT_MODE_DEADLINE);
1195 		la->la_timer_period = (et->et_frequency * first) >> 32;
1196 		lapic_timer_deadline(la);
1197 	} else {
1198 		lapic_change_mode(et, la, LAT_MODE_ONESHOT);
1199 		la->la_timer_period = ((uint32_t)et->et_frequency * first) >>
1200 		    32;
1201 		lapic_timer_oneshot(la);
1202 	}
1203 	return (0);
1204 }
1205 
1206 static int
lapic_et_stop(struct eventtimer * et)1207 lapic_et_stop(struct eventtimer *et)
1208 {
1209 	struct lapic *la;
1210 
1211 	la = &lapics[PCPU_GET(apic_id)];
1212 	lapic_timer_stop(la);
1213 	la->la_timer_mode = LAT_MODE_UNDEF;
1214 	return (0);
1215 }
1216 
1217 void
lapic_disable(void)1218 lapic_disable(void)
1219 {
1220 	uint32_t value;
1221 
1222 	/* Software disable the local APIC. */
1223 	value = lapic_read32(LAPIC_SVR);
1224 	value &= ~APIC_SVR_SWEN;
1225 	lapic_write32(LAPIC_SVR, value);
1226 }
1227 
1228 static void
lapic_enable(void)1229 lapic_enable(void)
1230 {
1231 	uint32_t value;
1232 
1233 	/* Program the spurious vector to enable the local APIC. */
1234 	value = lapic_read32(LAPIC_SVR);
1235 	value &= ~(APIC_SVR_VECTOR | APIC_SVR_FOCUS);
1236 	value |= APIC_SVR_FEN | APIC_SVR_SWEN | APIC_SPURIOUS_INT;
1237 	if (lapic_eoi_suppression)
1238 		value |= APIC_SVR_EOI_SUPPRESSION;
1239 	lapic_write32(LAPIC_SVR, value);
1240 }
1241 
1242 /* Reset the local APIC on the BSP during resume. */
1243 static void
lapic_resume(struct pic * pic,bool suspend_cancelled)1244 lapic_resume(struct pic *pic, bool suspend_cancelled)
1245 {
1246 
1247 	lapic_setup(0);
1248 }
1249 
1250 int
lapic_id(void)1251 lapic_id(void)
1252 {
1253 	uint32_t v;
1254 
1255 	KASSERT(x2apic_mode || lapic_map != NULL, ("local APIC is not mapped"));
1256 	v = lapic_read32(LAPIC_ID);
1257 	if (!x2apic_mode)
1258 		v >>= APIC_ID_SHIFT;
1259 	return (v);
1260 }
1261 
1262 int
lapic_intr_pending(u_int vector)1263 lapic_intr_pending(u_int vector)
1264 {
1265 	uint32_t irr;
1266 
1267 	/*
1268 	 * The IRR registers are an array of registers each of which
1269 	 * only describes 32 interrupts in the low 32 bits.  Thus, we
1270 	 * divide the vector by 32 to get the register index.
1271 	 * Finally, we modulus the vector by 32 to determine the
1272 	 * individual bit to test.
1273 	 */
1274 	irr = lapic_read32(LAPIC_IRR0 + vector / 32);
1275 	return (irr & 1 << (vector % 32));
1276 }
1277 
1278 void
lapic_set_logical_id(u_int apic_id,u_int cluster,u_int cluster_id)1279 lapic_set_logical_id(u_int apic_id, u_int cluster, u_int cluster_id)
1280 {
1281 	struct lapic *la;
1282 
1283 	KASSERT(lapics[apic_id].la_present, ("%s: APIC %u doesn't exist",
1284 	    __func__, apic_id));
1285 	KASSERT(cluster <= APIC_MAX_CLUSTER, ("%s: cluster %u too big",
1286 	    __func__, cluster));
1287 	KASSERT(cluster_id <= APIC_MAX_INTRACLUSTER_ID,
1288 	    ("%s: intra cluster id %u too big", __func__, cluster_id));
1289 	la = &lapics[apic_id];
1290 	la->la_cluster = cluster;
1291 	la->la_cluster_id = cluster_id;
1292 }
1293 
1294 int
lapic_set_lvt_mask(u_int apic_id,u_int pin,u_char masked)1295 lapic_set_lvt_mask(u_int apic_id, u_int pin, u_char masked)
1296 {
1297 
1298 	if (pin > APIC_LVT_MAX)
1299 		return (EINVAL);
1300 	if (apic_id == APIC_ID_ALL) {
1301 		lvts[pin].lvt_masked = masked;
1302 		if (bootverbose)
1303 			printf("lapic:");
1304 	} else {
1305 		KASSERT(lapics[apic_id].la_present,
1306 		    ("%s: missing APIC %u", __func__, apic_id));
1307 		lapics[apic_id].la_lvts[pin].lvt_masked = masked;
1308 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1309 		if (bootverbose)
1310 			printf("lapic%u:", apic_id);
1311 	}
1312 	if (bootverbose)
1313 		printf(" LINT%u %s\n", pin, masked ? "masked" : "unmasked");
1314 	return (0);
1315 }
1316 
1317 int
lapic_set_lvt_mode(u_int apic_id,u_int pin,u_int32_t mode)1318 lapic_set_lvt_mode(u_int apic_id, u_int pin, u_int32_t mode)
1319 {
1320 	struct lvt *lvt;
1321 
1322 	if (pin > APIC_LVT_MAX)
1323 		return (EINVAL);
1324 	if (apic_id == APIC_ID_ALL) {
1325 		lvt = &lvts[pin];
1326 		if (bootverbose)
1327 			printf("lapic:");
1328 	} else {
1329 		KASSERT(lapics[apic_id].la_present,
1330 		    ("%s: missing APIC %u", __func__, apic_id));
1331 		lvt = &lapics[apic_id].la_lvts[pin];
1332 		lvt->lvt_active = 1;
1333 		if (bootverbose)
1334 			printf("lapic%u:", apic_id);
1335 	}
1336 	lvt->lvt_mode = mode;
1337 	switch (mode) {
1338 	case APIC_LVT_DM_NMI:
1339 	case APIC_LVT_DM_SMI:
1340 	case APIC_LVT_DM_INIT:
1341 	case APIC_LVT_DM_EXTINT:
1342 		lvt->lvt_edgetrigger = 1;
1343 		lvt->lvt_activehi = 1;
1344 		if (mode == APIC_LVT_DM_EXTINT)
1345 			lvt->lvt_masked = 1;
1346 		else
1347 			lvt->lvt_masked = 0;
1348 		break;
1349 	default:
1350 		panic("Unsupported delivery mode: 0x%x\n", mode);
1351 	}
1352 	if (bootverbose) {
1353 		printf(" Routing ");
1354 		switch (mode) {
1355 		case APIC_LVT_DM_NMI:
1356 			printf("NMI");
1357 			break;
1358 		case APIC_LVT_DM_SMI:
1359 			printf("SMI");
1360 			break;
1361 		case APIC_LVT_DM_INIT:
1362 			printf("INIT");
1363 			break;
1364 		case APIC_LVT_DM_EXTINT:
1365 			printf("ExtINT");
1366 			break;
1367 		}
1368 		printf(" -> LINT%u\n", pin);
1369 	}
1370 	return (0);
1371 }
1372 
1373 int
lapic_set_lvt_polarity(u_int apic_id,u_int pin,enum intr_polarity pol)1374 lapic_set_lvt_polarity(u_int apic_id, u_int pin, enum intr_polarity pol)
1375 {
1376 
1377 	if (pin > APIC_LVT_MAX || pol == INTR_POLARITY_CONFORM)
1378 		return (EINVAL);
1379 	if (apic_id == APIC_ID_ALL) {
1380 		lvts[pin].lvt_activehi = (pol == INTR_POLARITY_HIGH);
1381 		if (bootverbose)
1382 			printf("lapic:");
1383 	} else {
1384 		KASSERT(lapics[apic_id].la_present,
1385 		    ("%s: missing APIC %u", __func__, apic_id));
1386 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1387 		lapics[apic_id].la_lvts[pin].lvt_activehi =
1388 		    (pol == INTR_POLARITY_HIGH);
1389 		if (bootverbose)
1390 			printf("lapic%u:", apic_id);
1391 	}
1392 	if (bootverbose)
1393 		printf(" LINT%u polarity: %s\n", pin,
1394 		    pol == INTR_POLARITY_HIGH ? "high" : "low");
1395 	return (0);
1396 }
1397 
1398 int
lapic_set_lvt_triggermode(u_int apic_id,u_int pin,enum intr_trigger trigger)1399 lapic_set_lvt_triggermode(u_int apic_id, u_int pin,
1400      enum intr_trigger trigger)
1401 {
1402 
1403 	if (pin > APIC_LVT_MAX || trigger == INTR_TRIGGER_CONFORM)
1404 		return (EINVAL);
1405 	if (apic_id == APIC_ID_ALL) {
1406 		lvts[pin].lvt_edgetrigger = (trigger == INTR_TRIGGER_EDGE);
1407 		if (bootverbose)
1408 			printf("lapic:");
1409 	} else {
1410 		KASSERT(lapics[apic_id].la_present,
1411 		    ("%s: missing APIC %u", __func__, apic_id));
1412 		lapics[apic_id].la_lvts[pin].lvt_edgetrigger =
1413 		    (trigger == INTR_TRIGGER_EDGE);
1414 		lapics[apic_id].la_lvts[pin].lvt_active = 1;
1415 		if (bootverbose)
1416 			printf("lapic%u:", apic_id);
1417 	}
1418 	if (bootverbose)
1419 		printf(" LINT%u trigger: %s\n", pin,
1420 		    trigger == INTR_TRIGGER_EDGE ? "edge" : "level");
1421 	return (0);
1422 }
1423 
1424 /*
1425  * Adjust the TPR of the current CPU so that it blocks all interrupts below
1426  * the passed in vector.
1427  */
1428 static void
lapic_set_tpr(u_int vector)1429 lapic_set_tpr(u_int vector)
1430 {
1431 #ifdef CHEAP_TPR
1432 	lapic_write32(LAPIC_TPR, vector);
1433 #else
1434 	uint32_t tpr;
1435 
1436 	tpr = lapic_read32(LAPIC_TPR) & ~APIC_TPR_PRIO;
1437 	tpr |= vector;
1438 	lapic_write32(LAPIC_TPR, tpr);
1439 #endif
1440 }
1441 
1442 void
lapic_eoi(void)1443 lapic_eoi(void)
1444 {
1445 
1446 	lapic_write32_nofence(LAPIC_EOI, 0);
1447 }
1448 
1449 void
lapic_handle_intr(int vector,struct trapframe * frame)1450 lapic_handle_intr(int vector, struct trapframe *frame)
1451 {
1452 	struct intsrc *isrc;
1453 
1454 	kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0);
1455 	kmsan_mark(&vector, sizeof(vector), KMSAN_STATE_INITED);
1456 	kmsan_mark(frame, sizeof(*frame), KMSAN_STATE_INITED);
1457 	trap_check_kstack();
1458 
1459 	isrc = intr_lookup_source(apic_idt_to_irq(PCPU_GET(apic_id),
1460 	    vector));
1461 	KASSERT(isrc != NULL,
1462 	    ("lapic_handle_intr: vector %d unrecognized at lapic %u",
1463 	    vector, PCPU_GET(apic_id)));
1464 	intr_execute_handlers(isrc, frame);
1465 }
1466 
1467 void
lapic_handle_timer(struct trapframe * frame)1468 lapic_handle_timer(struct trapframe *frame)
1469 {
1470 	struct lapic *la;
1471 	struct trapframe *oldframe;
1472 	struct thread *td;
1473 
1474 	/* Send EOI first thing. */
1475 	lapic_eoi();
1476 
1477 	kasan_mark(frame, sizeof(*frame), sizeof(*frame), 0);
1478 	kmsan_mark(frame, sizeof(*frame), KMSAN_STATE_INITED);
1479 	trap_check_kstack();
1480 
1481 	/* Look up our local APIC structure for the tick counters. */
1482 	la = &lapics[PCPU_GET(apic_id)];
1483 	(*la->la_timer_count)++;
1484 	critical_enter();
1485 	if (lapic_et.et_active) {
1486 		td = curthread;
1487 		td->td_intr_nesting_level++;
1488 		oldframe = td->td_intr_frame;
1489 		td->td_intr_frame = frame;
1490 		lapic_et.et_event_cb(&lapic_et, lapic_et.et_arg);
1491 		td->td_intr_frame = oldframe;
1492 		td->td_intr_nesting_level--;
1493 	}
1494 	critical_exit();
1495 }
1496 
1497 static void
lapic_timer_set_divisor(u_int divisor)1498 lapic_timer_set_divisor(u_int divisor)
1499 {
1500 
1501 	KASSERT(powerof2(divisor), ("lapic: invalid divisor %u", divisor));
1502 	KASSERT(ffs(divisor) <= nitems(lapic_timer_divisors),
1503 		("lapic: invalid divisor %u", divisor));
1504 	lapic_write32(LAPIC_DCR_TIMER, lapic_timer_divisors[ffs(divisor) - 1]);
1505 }
1506 
1507 static void
lapic_timer_oneshot(struct lapic * la)1508 lapic_timer_oneshot(struct lapic *la)
1509 {
1510 	uint32_t value;
1511 
1512 	value = la->lvt_timer_base;
1513 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1514 	value |= APIC_LVTT_TM_ONE_SHOT;
1515 	la->lvt_timer_last = value;
1516 	lapic_write32(LAPIC_LVT_TIMER, value);
1517 	lapic_write32(LAPIC_ICR_TIMER, la->la_timer_period);
1518 }
1519 
1520 static void
lapic_timer_oneshot_nointr(struct lapic * la,uint32_t count)1521 lapic_timer_oneshot_nointr(struct lapic *la, uint32_t count)
1522 {
1523 	uint32_t value;
1524 
1525 	value = la->lvt_timer_base;
1526 	value &= ~APIC_LVTT_TM;
1527 	value |= APIC_LVTT_TM_ONE_SHOT | APIC_LVT_M;
1528 	la->lvt_timer_last = value;
1529 	lapic_write32(LAPIC_LVT_TIMER, value);
1530 	lapic_write32(LAPIC_ICR_TIMER, count);
1531 }
1532 
1533 static void
lapic_timer_periodic(struct lapic * la)1534 lapic_timer_periodic(struct lapic *la)
1535 {
1536 	uint32_t value;
1537 
1538 	value = la->lvt_timer_base;
1539 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1540 	value |= APIC_LVTT_TM_PERIODIC;
1541 	la->lvt_timer_last = value;
1542 	lapic_write32(LAPIC_LVT_TIMER, value);
1543 	lapic_write32(LAPIC_ICR_TIMER, la->la_timer_period);
1544 }
1545 
1546 static void
lapic_timer_deadline(struct lapic * la)1547 lapic_timer_deadline(struct lapic *la)
1548 {
1549 	uint32_t value;
1550 
1551 	value = la->lvt_timer_base;
1552 	value &= ~(APIC_LVTT_TM | APIC_LVT_M);
1553 	value |= APIC_LVTT_TM_TSCDLT;
1554 	if (value != la->lvt_timer_last) {
1555 		la->lvt_timer_last = value;
1556 		lapic_write32_nofence(LAPIC_LVT_TIMER, value);
1557 		if (!x2apic_mode)
1558 			mfence();
1559 	}
1560 	wrmsr(MSR_TSC_DEADLINE, la->la_timer_period + rdtsc());
1561 }
1562 
1563 static void
lapic_timer_stop(struct lapic * la)1564 lapic_timer_stop(struct lapic *la)
1565 {
1566 	uint32_t value;
1567 
1568 	if (la->la_timer_mode == LAT_MODE_DEADLINE) {
1569 		wrmsr(MSR_TSC_DEADLINE, 0);
1570 		mfence();
1571 	} else {
1572 		value = la->lvt_timer_base;
1573 		value &= ~APIC_LVTT_TM;
1574 		value |= APIC_LVT_M;
1575 		la->lvt_timer_last = value;
1576 		lapic_write32(LAPIC_LVT_TIMER, value);
1577 	}
1578 }
1579 
1580 void
lapic_handle_cmc(void)1581 lapic_handle_cmc(void)
1582 {
1583 	trap_check_kstack();
1584 
1585 	lapic_eoi();
1586 	cmc_intr();
1587 }
1588 
1589 /*
1590  * Called from the mca_init() to activate the CMC interrupt if this CPU is
1591  * responsible for monitoring any MC banks for CMC events.  Since mca_init()
1592  * is called prior to lapic_setup() during boot, this just needs to unmask
1593  * this CPU's LVT_CMCI entry.
1594  */
1595 void
lapic_enable_cmc(void)1596 lapic_enable_cmc(void)
1597 {
1598 	u_int apic_id;
1599 
1600 #ifdef DEV_ATPIC
1601 	if (!x2apic_mode && lapic_map == NULL)
1602 		return;
1603 #endif
1604 	apic_id = PCPU_GET(apic_id);
1605 	KASSERT(lapics[apic_id].la_present,
1606 	    ("%s: missing APIC %u", __func__, apic_id));
1607 	lapics[apic_id].la_lvts[APIC_LVT_CMCI].lvt_masked = 0;
1608 	lapics[apic_id].la_lvts[APIC_LVT_CMCI].lvt_active = 1;
1609 }
1610 
1611 int
lapic_enable_mca_elvt(void)1612 lapic_enable_mca_elvt(void)
1613 {
1614 	u_int apic_id;
1615 	uint32_t value;
1616 	int elvt_count;
1617 
1618 #ifdef DEV_ATPIC
1619 	if (lapic_map == NULL)
1620 		return (-1);
1621 #endif
1622 
1623 	apic_id = PCPU_GET(apic_id);
1624 	KASSERT(lapics[apic_id].la_present,
1625 	    ("%s: missing APIC %u", __func__, apic_id));
1626 	elvt_count = amd_read_elvt_count();
1627 	if (elvt_count <= APIC_ELVT_MCA)
1628 		return (-1);
1629 
1630 	value = lapic_read32(LAPIC_EXT_LVT0 + APIC_ELVT_MCA);
1631 	if ((value & APIC_LVT_M) == 0) {
1632 		if (bootverbose)
1633 			printf("AMD MCE Thresholding Extended LVT is already active\n");
1634 		return (APIC_ELVT_MCA);
1635 	}
1636 	lapics[apic_id].la_elvts[APIC_ELVT_MCA].lvt_masked = 0;
1637 	lapics[apic_id].la_elvts[APIC_ELVT_MCA].lvt_active = 1;
1638 	return (APIC_ELVT_MCA);
1639 }
1640 
1641 void
lapic_handle_thermal(void)1642 lapic_handle_thermal(void)
1643 {
1644 	lapic_thermal_handler_t *func;
1645 
1646 	func = (lapic_thermal_handler_t *)atomic_load_acq_ptr(
1647 	    (uintptr_t *)&lapic_thermal_function);
1648 
1649 	if (func != NULL)
1650 		func(PCPU_GET(cpuid), lapic_thermal_function_arg);
1651 
1652 	lapic_eoi();
1653 }
1654 
1655 static void
lapic_update_thermal(void * dummy __unused)1656 lapic_update_thermal(void *dummy __unused)
1657 {
1658 	struct lapic *la;
1659 
1660 	la = &lapics[lapic_id()];
1661 	lapic_write32(LAPIC_LVT_THERMAL, lvt_mode(la, APIC_LVT_THERMAL,
1662 	    lapic_read32(LAPIC_LVT_THERMAL)));
1663 }
1664 
1665 bool
lapic_enable_thermal(lapic_thermal_handler_t * func,void * func_arg)1666 lapic_enable_thermal(lapic_thermal_handler_t *func, void *func_arg)
1667 {
1668 #ifdef DEV_ATPIC
1669 	/* Fail if the local APIC is not present. */
1670 	if (!x2apic_mode && lapic_map == NULL)
1671 		return (false);
1672 #endif
1673 
1674 	if (lapic_maxlvt() < APIC_LVT_THERMAL)
1675 		return (false);
1676 
1677 	lapic_thermal_function_arg = func_arg;
1678 	atomic_store_rel_ptr((uintptr_t *)&lapic_thermal_function,
1679 	    (uintptr_t)func);
1680 
1681 	lvts[APIC_LVT_THERMAL].lvt_masked = 0;
1682 
1683 	MPASS(mp_ncpus == 1 || smp_started);
1684 	smp_rendezvous(NULL, lapic_update_thermal, NULL, NULL);
1685 
1686 	return (true);
1687 }
1688 
1689 void
lapic_disable_thermal(void)1690 lapic_disable_thermal(void)
1691 {
1692 #ifdef DEV_ATPIC
1693 	/* Fail if the local APIC is not present. */
1694 	if (!x2apic_mode && lapic_map == NULL)
1695 		return;
1696 #endif
1697 
1698 	if (lapic_maxlvt() < APIC_LVT_THERMAL)
1699 		return;
1700 
1701 	lvts[APIC_LVT_THERMAL].lvt_masked = 1;
1702 
1703 #ifdef SMP
1704 	KASSERT(mp_ncpus == 1 || smp_started, ("thermal driver unloaded too early"));
1705 #endif
1706 	smp_rendezvous(NULL, lapic_update_thermal, NULL, NULL);
1707 
1708 	atomic_store_rel_ptr((uintptr_t *)&lapic_thermal_function,
1709 	    (uintptr_t)NULL);
1710 }
1711 
1712 void
lapic_handle_error(void)1713 lapic_handle_error(void)
1714 {
1715 	uint32_t esr;
1716 
1717 	trap_check_kstack();
1718 
1719 	/*
1720 	 * Read the contents of the error status register.  Write to
1721 	 * the register first before reading from it to force the APIC
1722 	 * to update its value to indicate any errors that have
1723 	 * occurred since the previous write to the register.
1724 	 */
1725 	lapic_write32(LAPIC_ESR, 0);
1726 	esr = lapic_read32(LAPIC_ESR);
1727 
1728 	printf("CPU%d: local APIC error 0x%x\n", PCPU_GET(cpuid), esr);
1729 	lapic_eoi();
1730 }
1731 
1732 u_int
apic_cpuid(u_int apic_id)1733 apic_cpuid(u_int apic_id)
1734 {
1735 #ifdef SMP
1736 	return apic_cpuids[apic_id];
1737 #else
1738 	return 0;
1739 #endif
1740 }
1741 
1742 /* Request a free IDT vector to be used by the specified IRQ. */
1743 u_int
apic_alloc_vector(u_int apic_id,u_int irq)1744 apic_alloc_vector(u_int apic_id, u_int irq)
1745 {
1746 	u_int vector;
1747 
1748 	KASSERT(irq < num_io_irqs, ("Invalid IRQ %u", irq));
1749 
1750 	/*
1751 	 * Search for a free vector.  Currently we just use a very simple
1752 	 * algorithm to find the first free vector.
1753 	 */
1754 	mtx_lock_spin(&icu_lock);
1755 	for (vector = 0; vector < APIC_NUM_IOINTS; vector++) {
1756 		if (lapics[apic_id].la_ioint_irqs[vector] != IRQ_FREE)
1757 			continue;
1758 		lapics[apic_id].la_ioint_irqs[vector] = irq;
1759 		mtx_unlock_spin(&icu_lock);
1760 		return (vector + APIC_IO_INTS);
1761 	}
1762 	mtx_unlock_spin(&icu_lock);
1763 	return (0);
1764 }
1765 
1766 /*
1767  * Request 'count' free contiguous IDT vectors to be used by 'count'
1768  * IRQs.  'count' must be a power of two and the vectors will be
1769  * aligned on a boundary of 'align'.  If the request cannot be
1770  * satisfied, 0 is returned.
1771  */
1772 u_int
apic_alloc_vectors(u_int apic_id,u_int * irqs,u_int count,u_int align)1773 apic_alloc_vectors(u_int apic_id, u_int *irqs, u_int count, u_int align)
1774 {
1775 	u_int first, run, vector;
1776 
1777 	KASSERT(powerof2(count), ("bad count"));
1778 	KASSERT(powerof2(align), ("bad align"));
1779 	KASSERT(align >= count, ("align < count"));
1780 #ifdef INVARIANTS
1781 	for (run = 0; run < count; run++)
1782 		KASSERT(irqs[run] < num_io_irqs, ("Invalid IRQ %u at index %u",
1783 		    irqs[run], run));
1784 #endif
1785 
1786 	/*
1787 	 * Search for 'count' free vectors.  As with apic_alloc_vector(),
1788 	 * this just uses a simple first fit algorithm.
1789 	 */
1790 	run = 0;
1791 	first = 0;
1792 	mtx_lock_spin(&icu_lock);
1793 	for (vector = 0; vector < APIC_NUM_IOINTS; vector++) {
1794 		/* Vector is in use, end run. */
1795 		if (lapics[apic_id].la_ioint_irqs[vector] != IRQ_FREE) {
1796 			run = 0;
1797 			first = 0;
1798 			continue;
1799 		}
1800 
1801 		/* Start a new run if run == 0 and vector is aligned. */
1802 		if (run == 0) {
1803 			if (((vector + APIC_IO_INTS) & (align - 1)) != 0)
1804 				continue;
1805 			first = vector;
1806 		}
1807 		run++;
1808 
1809 		/* Keep looping if the run isn't long enough yet. */
1810 		if (run < count)
1811 			continue;
1812 
1813 		/* Found a run, assign IRQs and return the first vector. */
1814 		for (vector = 0; vector < count; vector++)
1815 			lapics[apic_id].la_ioint_irqs[first + vector] =
1816 			    irqs[vector];
1817 		mtx_unlock_spin(&icu_lock);
1818 		return (first + APIC_IO_INTS);
1819 	}
1820 	mtx_unlock_spin(&icu_lock);
1821 	printf("APIC: Couldn't find APIC vectors for %u IRQs\n", count);
1822 	return (0);
1823 }
1824 
1825 /*
1826  * Enable a vector for a particular apic_id.  Since all lapics share idt
1827  * entries and ioint_handlers this enables the vector on all lapics.  lapics
1828  * which do not have the vector configured would report spurious interrupts
1829  * should it fire.
1830  */
1831 void
apic_enable_vector(u_int apic_id,u_int vector)1832 apic_enable_vector(u_int apic_id, u_int vector)
1833 {
1834 
1835 	KASSERT(vector != IDT_SYSCALL, ("Attempt to overwrite syscall entry"));
1836 	KASSERT(ioint_handlers[vector / 32] != NULL,
1837 	    ("No ISR handler for vector %u", vector));
1838 #ifdef KDTRACE_HOOKS
1839 	KASSERT(vector != IDT_DTRACE_RET,
1840 	    ("Attempt to overwrite DTrace entry"));
1841 #endif
1842 	setidt(vector, (pti ? ioint_pti_handlers : ioint_handlers)[vector / 32],
1843 	    SDT_APIC, SEL_KPL, GSEL_APIC);
1844 }
1845 
1846 void
apic_disable_vector(u_int apic_id,u_int vector)1847 apic_disable_vector(u_int apic_id, u_int vector)
1848 {
1849 
1850 	KASSERT(vector != IDT_SYSCALL, ("Attempt to overwrite syscall entry"));
1851 #ifdef KDTRACE_HOOKS
1852 	KASSERT(vector != IDT_DTRACE_RET,
1853 	    ("Attempt to overwrite DTrace entry"));
1854 #endif
1855 	KASSERT(ioint_handlers[vector / 32] != NULL,
1856 	    ("No ISR handler for vector %u", vector));
1857 #ifdef notyet
1858 	/*
1859 	 * We can not currently clear the idt entry because other cpus
1860 	 * may have a valid vector at this offset.
1861 	 */
1862 	setidt(vector, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd), SDT_APIC,
1863 	    SEL_KPL, GSEL_APIC);
1864 #endif
1865 }
1866 
1867 /* Release an APIC vector when it's no longer in use. */
1868 void
apic_free_vector(u_int apic_id,u_int vector,u_int irq)1869 apic_free_vector(u_int apic_id, u_int vector, u_int irq)
1870 {
1871 	struct thread *td;
1872 
1873 	KASSERT(vector >= APIC_IO_INTS && vector != IDT_SYSCALL &&
1874 	    vector <= APIC_IO_INTS + APIC_NUM_IOINTS,
1875 	    ("Vector %u does not map to an IRQ line", vector));
1876 	KASSERT(irq < num_io_irqs, ("Invalid IRQ %u", irq));
1877 	KASSERT(lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS] ==
1878 	    irq, ("IRQ mismatch"));
1879 #ifdef KDTRACE_HOOKS
1880 	KASSERT(vector != IDT_DTRACE_RET,
1881 	    ("Attempt to overwrite DTrace entry"));
1882 #endif
1883 
1884 	/*
1885 	 * Bind us to the cpu that owned the vector before freeing it so
1886 	 * we don't lose an interrupt delivery race.
1887 	 */
1888 	td = curthread;
1889 	if (!rebooting) {
1890 		thread_lock(td);
1891 		if (sched_is_bound(td))
1892 			panic("apic_free_vector: Thread already bound.\n");
1893 		sched_bind(td, apic_cpuid(apic_id));
1894 		thread_unlock(td);
1895 	}
1896 	mtx_lock_spin(&icu_lock);
1897 	lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS] = IRQ_FREE;
1898 	mtx_unlock_spin(&icu_lock);
1899 	if (!rebooting) {
1900 		thread_lock(td);
1901 		sched_unbind(td);
1902 		thread_unlock(td);
1903 	}
1904 }
1905 
1906 /* Map an IDT vector (APIC) to an IRQ (interrupt source). */
1907 static u_int
apic_idt_to_irq(u_int apic_id,u_int vector)1908 apic_idt_to_irq(u_int apic_id, u_int vector)
1909 {
1910 	int irq;
1911 
1912 	KASSERT(vector >= APIC_IO_INTS && vector != IDT_SYSCALL &&
1913 	    vector <= APIC_IO_INTS + APIC_NUM_IOINTS,
1914 	    ("Vector %u does not map to an IRQ line", vector));
1915 #ifdef KDTRACE_HOOKS
1916 	KASSERT(vector != IDT_DTRACE_RET,
1917 	    ("Attempt to overwrite DTrace entry"));
1918 #endif
1919 	irq = lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS];
1920 	if (irq < 0)
1921 		irq = 0;
1922 	return (irq);
1923 }
1924 
1925 #ifdef DDB
1926 /*
1927  * Dump data about APIC IDT vector mappings.
1928  */
DB_SHOW_COMMAND_FLAGS(apic,db_show_apic,DB_CMD_MEMSAFE)1929 DB_SHOW_COMMAND_FLAGS(apic, db_show_apic, DB_CMD_MEMSAFE)
1930 {
1931 	struct intsrc *isrc;
1932 	int i, verbose;
1933 	u_int apic_id;
1934 	u_int irq;
1935 
1936 	if (strcmp(modif, "vv") == 0)
1937 		verbose = 2;
1938 	else if (strcmp(modif, "v") == 0)
1939 		verbose = 1;
1940 	else
1941 		verbose = 0;
1942 	for (apic_id = 0; apic_id <= max_apic_id; apic_id++) {
1943 		if (lapics[apic_id].la_present == 0)
1944 			continue;
1945 		db_printf("Interrupts bound to lapic %u\n", apic_id);
1946 		for (i = 0; i < APIC_NUM_IOINTS + 1 && !db_pager_quit; i++) {
1947 			irq = lapics[apic_id].la_ioint_irqs[i];
1948 			if (irq == IRQ_FREE || irq == IRQ_SYSCALL)
1949 				continue;
1950 #ifdef KDTRACE_HOOKS
1951 			if (irq == IRQ_DTRACE_RET)
1952 				continue;
1953 #endif
1954 #ifdef XENHVM
1955 			if (irq == IRQ_EVTCHN)
1956 				continue;
1957 #endif
1958 			db_printf("vec 0x%2x -> ", i + APIC_IO_INTS);
1959 			if (irq == IRQ_TIMER)
1960 				db_printf("lapic timer\n");
1961 			else if (irq < num_io_irqs) {
1962 				isrc = intr_lookup_source(irq);
1963 				if (isrc == NULL || verbose == 0)
1964 					db_printf("IRQ %u\n", irq);
1965 				else
1966 					db_dump_intr_event(isrc->is_event,
1967 					    verbose == 2);
1968 			} else
1969 				db_printf("IRQ %u ???\n", irq);
1970 		}
1971 	}
1972 }
1973 
1974 static void
dump_mask(const char * prefix,uint32_t v,int base)1975 dump_mask(const char *prefix, uint32_t v, int base)
1976 {
1977 	int i, first;
1978 
1979 	first = 1;
1980 	for (i = 0; i < 32; i++)
1981 		if (v & (1 << i)) {
1982 			if (first) {
1983 				db_printf("%s:", prefix);
1984 				first = 0;
1985 			}
1986 			db_printf(" %02x", base + i);
1987 		}
1988 	if (!first)
1989 		db_printf("\n");
1990 }
1991 
1992 /* Show info from the lapic regs for this CPU. */
DB_SHOW_COMMAND_FLAGS(lapic,db_show_lapic,DB_CMD_MEMSAFE)1993 DB_SHOW_COMMAND_FLAGS(lapic, db_show_lapic, DB_CMD_MEMSAFE)
1994 {
1995 	const struct lvt *l;
1996 	int elvt_count, lvts_count, i;
1997 	const uint32_t v = lapic_version();
1998 	const int maxlvt = lapic_version_maxlvt(v);
1999 	const uint32_t vr = lapic_read32(LAPIC_SVR);
2000 
2001 	db_printf("lapic ID = %d\n", lapic_id());
2002 	db_printf("version  = %d.%d (%#x) \n", (v & APIC_VER_VERSION) >> 4,
2003 	    v & 0xf, v);
2004 	db_printf("max LVT  = %d\n", maxlvt);
2005 	db_printf("SVR      = %02x (%s)\n", vr & APIC_SVR_VECTOR,
2006 	    vr & APIC_SVR_ENABLE ? "enabled" : "disabled");
2007 	db_printf("TPR      = %02x\n", lapic_read32(LAPIC_TPR));
2008 
2009 	lvts_count = min(nitems(lvts), maxlvt + 1);
2010 	for (i = 0; i < lvts_count; i++) {
2011 		l = &lvts[i];
2012 		db_printf("LVT%d  (reg %#x %-5s) = %#010x\n", i, l->lvt_reg,
2013 		    l->lvt_desc, lapic_read32(l->lvt_reg));
2014 	}
2015 
2016 	elvt_count = amd_read_elvt_count();
2017 	for (i = 0; i < elvt_count; i++) {
2018 		l = &elvts[i];
2019 		db_printf("ELVT%d (reg %#x %-5s) = %#010x\n", i, l->lvt_reg,
2020 		    l->lvt_desc, lapic_read32(l->lvt_reg));
2021 	}
2022 
2023 #define dump_field(prefix, regn, index)					\
2024 	dump_mask(__XSTRING(prefix ## index), 				\
2025 	    lapic_read32(LAPIC_ ## regn ## index),			\
2026 	    index * 32)
2027 
2028 	db_printf("In-service Interrupts:\n");
2029 	dump_field(isr, ISR, 0);
2030 	dump_field(isr, ISR, 1);
2031 	dump_field(isr, ISR, 2);
2032 	dump_field(isr, ISR, 3);
2033 	dump_field(isr, ISR, 4);
2034 	dump_field(isr, ISR, 5);
2035 	dump_field(isr, ISR, 6);
2036 	dump_field(isr, ISR, 7);
2037 
2038 	db_printf("TMR Interrupts:\n");
2039 	dump_field(tmr, TMR, 0);
2040 	dump_field(tmr, TMR, 1);
2041 	dump_field(tmr, TMR, 2);
2042 	dump_field(tmr, TMR, 3);
2043 	dump_field(tmr, TMR, 4);
2044 	dump_field(tmr, TMR, 5);
2045 	dump_field(tmr, TMR, 6);
2046 	dump_field(tmr, TMR, 7);
2047 
2048 	db_printf("IRR Interrupts:\n");
2049 	dump_field(irr, IRR, 0);
2050 	dump_field(irr, IRR, 1);
2051 	dump_field(irr, IRR, 2);
2052 	dump_field(irr, IRR, 3);
2053 	dump_field(irr, IRR, 4);
2054 	dump_field(irr, IRR, 5);
2055 	dump_field(irr, IRR, 6);
2056 	dump_field(irr, IRR, 7);
2057 
2058 #undef dump_field
2059 }
2060 #endif
2061 
2062 /*
2063  * APIC probing support code.  This includes code to manage enumerators.
2064  */
2065 
2066 static SLIST_HEAD(, apic_enumerator) enumerators =
2067 	SLIST_HEAD_INITIALIZER(enumerators);
2068 static struct apic_enumerator *best_enum;
2069 
2070 void
apic_register_enumerator(struct apic_enumerator * enumerator)2071 apic_register_enumerator(struct apic_enumerator *enumerator)
2072 {
2073 #ifdef INVARIANTS
2074 	struct apic_enumerator *apic_enum;
2075 
2076 	SLIST_FOREACH(apic_enum, &enumerators, apic_next) {
2077 		if (apic_enum == enumerator)
2078 			panic("%s: Duplicate register of %s", __func__,
2079 			    enumerator->apic_name);
2080 	}
2081 #endif
2082 	SLIST_INSERT_HEAD(&enumerators, enumerator, apic_next);
2083 }
2084 
2085 /*
2086  * We have to look for CPU's very, very early because certain subsystems
2087  * want to know how many CPU's we have extremely early on in the boot
2088  * process.
2089  */
2090 static void
apic_init(void * dummy __unused)2091 apic_init(void *dummy __unused)
2092 {
2093 	struct apic_enumerator *enumerator;
2094 	int retval, best;
2095 
2096 	/* We only support built in local APICs. */
2097 	if (!(cpu_feature & CPUID_APIC))
2098 		return;
2099 
2100 	/* Don't probe if APIC mode is disabled. */
2101 	if (resource_disabled("apic", 0))
2102 		return;
2103 
2104 	/* Probe all the enumerators to find the best match. */
2105 	best_enum = NULL;
2106 	best = 0;
2107 	SLIST_FOREACH(enumerator, &enumerators, apic_next) {
2108 		retval = enumerator->apic_probe();
2109 		if (retval > 0)
2110 			continue;
2111 		if (best_enum == NULL || best < retval) {
2112 			best_enum = enumerator;
2113 			best = retval;
2114 		}
2115 	}
2116 	if (best_enum == NULL) {
2117 		if (bootverbose)
2118 			printf("APIC: Could not find any APICs.\n");
2119 #ifndef DEV_ATPIC
2120 		panic("running without device atpic requires a local APIC");
2121 #endif
2122 		return;
2123 	}
2124 
2125 	if (bootverbose)
2126 		printf("APIC: Using the %s enumerator.\n",
2127 		    best_enum->apic_name);
2128 
2129 #ifdef I686_CPU
2130 	/*
2131 	 * To work around an errata, we disable the local APIC on some
2132 	 * CPUs during early startup.  We need to turn the local APIC back
2133 	 * on on such CPUs now.
2134 	 */
2135 	ppro_reenable_apic();
2136 #endif
2137 
2138 	/* Probe the CPU's in the system. */
2139 	retval = best_enum->apic_probe_cpus();
2140 	if (retval != 0)
2141 		printf("%s: Failed to probe CPUs: returned %d\n",
2142 		    best_enum->apic_name, retval);
2143 
2144 }
2145 SYSINIT(apic_init, SI_SUB_FIRST, SI_ORDER_SECOND, apic_init, NULL);
2146 
2147 /*
2148  * Setup the local APIC.  We have to do this prior to starting up the APs
2149  * in the SMP case.
2150  */
2151 static void
apic_setup_local(void * dummy __unused)2152 apic_setup_local(void *dummy __unused)
2153 {
2154 	int retval;
2155 
2156 	if (best_enum == NULL)
2157 		return;
2158 
2159 	lapics = malloc(sizeof(*lapics) * (max_apic_id + 1), M_LAPIC,
2160 	    M_WAITOK | M_ZERO);
2161 
2162 	/* Initialize the local APIC. */
2163 	retval = best_enum->apic_setup_local();
2164 	if (retval != 0)
2165 		printf("%s: Failed to setup the local APIC: returned %d\n",
2166 		    best_enum->apic_name, retval);
2167 }
2168 SYSINIT(apic_setup_local, SI_SUB_CPU, SI_ORDER_SECOND, apic_setup_local, NULL);
2169 
2170 /* Are we in a VM which supports the Extended Destination ID standard? */
2171 int apic_ext_dest_id = -1;
2172 SYSCTL_INT(_machdep, OID_AUTO, apic_ext_dest_id, CTLFLAG_RDTUN, &apic_ext_dest_id, 0,
2173     "Use APIC Extended Destination IDs");
2174 
2175 /* Detect support for Extended Destination IDs. */
2176 static void
detect_extended_dest_id(void)2177 detect_extended_dest_id(void)
2178 {
2179 	u_int regs[4];
2180 
2181 	/* Check if we support extended destination IDs. */
2182 	switch (vm_guest) {
2183 	case VM_GUEST_XEN:
2184 		cpuid_count(hv_base + 4, 0, regs);
2185 		if (regs[0] & XEN_HVM_CPUID_EXT_DEST_ID)
2186 			apic_ext_dest_id = 1;
2187 		break;
2188 	case VM_GUEST_HV:
2189 		cpuid_count(CPUID_LEAF_HV_STACK_INTERFACE, 0, regs);
2190 		if (regs[0] != HYPERV_STACK_INTERFACE_EAX_SIG)
2191 			break;
2192 		cpuid_count(CPUID_LEAF_HV_STACK_PROPERTIES, 0, regs);
2193 		if (regs[0] & HYPERV_PROPERTIES_EXT_DEST_ID)
2194 			apic_ext_dest_id = 1;
2195 		break;
2196 	case VM_GUEST_KVM:
2197 		kvm_cpuid_get_features(regs);
2198 		if (regs[0] & KVM_FEATURE_MSI_EXT_DEST_ID)
2199 			apic_ext_dest_id = 1;
2200 		break;
2201 	case VM_GUEST_BHYVE:
2202 		if (hv_high < CPUID_BHYVE_FEATURES)
2203 			break;
2204 		cpuid_count(CPUID_BHYVE_FEATURES, 0, regs);
2205 		if (regs[0] & CPUID_BHYVE_FEAT_EXT_DEST_ID)
2206 			apic_ext_dest_id = 1;
2207 		break;
2208 	}
2209 }
2210 
2211 /*
2212  * Setup the I/O APICs.
2213  */
2214 static void
apic_setup_io(void * dummy __unused)2215 apic_setup_io(void *dummy __unused)
2216 {
2217 	int retval;
2218 
2219 	if (best_enum == NULL)
2220 		return;
2221 
2222 	/* Check hypervisor support for extended destination IDs. */
2223 	if (apic_ext_dest_id == -1)
2224 		detect_extended_dest_id();
2225 
2226 	/*
2227 	 * Local APIC must be registered before other PICs and pseudo PICs
2228 	 * for proper suspend/resume order.
2229 	 */
2230 	intr_register_pic(&lapic_pic);
2231 
2232 	retval = best_enum->apic_setup_io();
2233 	if (retval != 0)
2234 		printf("%s: Failed to setup I/O APICs: returned %d\n",
2235 		    best_enum->apic_name, retval);
2236 
2237 	/*
2238 	 * Finish setting up the local APIC on the BSP once we know
2239 	 * how to properly program the LINT pins.  In particular, this
2240 	 * enables the EOI suppression mode, if LAPIC supports it and
2241 	 * user did not disable the mode.
2242 	 */
2243 	lapic_setup(1);
2244 	if (bootverbose)
2245 		lapic_dump("BSP");
2246 
2247 	/* Enable the MSI "pic". */
2248 	msi_init();
2249 
2250 #ifdef XENHVM
2251 	xen_intr_alloc_irqs();
2252 #endif
2253 }
2254 SYSINIT(apic_setup_io, SI_SUB_INTR, SI_ORDER_THIRD, apic_setup_io, NULL);
2255 
2256 #ifdef SMP
2257 /*
2258  * Inter Processor Interrupt functions.  The lapic_ipi_*() functions are
2259  * private to the MD code.  The public interface for the rest of the
2260  * kernel is defined in mp_machdep.c.
2261  */
2262 
2263 /*
2264  * Wait delay microseconds for IPI to be sent.  If delay is -1, we
2265  * wait forever.
2266  */
2267 int
lapic_ipi_wait(int delay)2268 lapic_ipi_wait(int delay)
2269 {
2270 	uint64_t rx;
2271 
2272 	/* LAPIC_ICR.APIC_DELSTAT_MASK is undefined in x2APIC mode */
2273 	if (x2apic_mode)
2274 		return (1);
2275 
2276 	for (rx = 0; delay == -1 || rx < lapic_ipi_wait_mult * delay; rx++) {
2277 		if ((lapic_read_icr_lo() & APIC_DELSTAT_MASK) ==
2278 		    APIC_DELSTAT_IDLE)
2279 			return (1);
2280 		ia32_pause();
2281 	}
2282 	return (0);
2283 }
2284 
2285 void
lapic_ipi_raw(register_t icrlo,u_int dest)2286 lapic_ipi_raw(register_t icrlo, u_int dest)
2287 {
2288 	uint32_t icrhi;
2289 
2290 	/* XXX: Need more sanity checking of icrlo? */
2291 	KASSERT(x2apic_mode || lapic_map != NULL,
2292 	    ("%s called too early", __func__));
2293 	KASSERT(x2apic_mode ||
2294 	    (dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
2295 	    ("%s: invalid dest field", __func__));
2296 	KASSERT((icrlo & APIC_ICRLO_RESV_MASK) == 0,
2297 	    ("%s: reserved bits set in ICR LO register", __func__));
2298 
2299 	if ((icrlo & APIC_DEST_MASK) == APIC_DEST_DESTFLD) {
2300 		if (x2apic_mode)
2301 			icrhi = dest;
2302 		else
2303 			icrhi = dest << APIC_ID_SHIFT;
2304 		lapic_write_icr(icrhi, icrlo);
2305 	} else {
2306 		lapic_write_icr_lo(icrlo);
2307 	}
2308 }
2309 
2310 #ifdef DETECT_DEADLOCK
2311 #define	AFTER_SPIN	50
2312 #endif
2313 
2314 static void
native_lapic_ipi_vectored(u_int vector,int dest)2315 native_lapic_ipi_vectored(u_int vector, int dest)
2316 {
2317 	register_t icrlo, destfield;
2318 
2319 	KASSERT((vector & ~APIC_VECTOR_MASK) == 0,
2320 	    ("%s: invalid vector %d", __func__, vector));
2321 
2322 	destfield = 0;
2323 	switch (dest) {
2324 	case APIC_IPI_DEST_SELF:
2325 		if (x2apic_mode && vector < IPI_NMI_FIRST) {
2326 			lapic_write_self_ipi(vector);
2327 			return;
2328 		}
2329 		icrlo = APIC_DEST_SELF;
2330 		break;
2331 	case APIC_IPI_DEST_ALL:
2332 		icrlo = APIC_DEST_ALLISELF;
2333 		break;
2334 	case APIC_IPI_DEST_OTHERS:
2335 		icrlo = APIC_DEST_ALLESELF;
2336 		break;
2337 	default:
2338 		icrlo = 0;
2339 		KASSERT(x2apic_mode ||
2340 		    (dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
2341 		    ("%s: invalid destination 0x%x", __func__, dest));
2342 		destfield = dest;
2343 	}
2344 
2345 	/*
2346 	 * NMI IPIs are just fake vectors used to send a NMI.  Use special rules
2347 	 * regarding NMIs if passed, otherwise specify the vector.
2348 	 */
2349 	if (vector >= IPI_NMI_FIRST)
2350 		icrlo |= APIC_DELMODE_NMI;
2351 	else
2352 		icrlo |= vector | APIC_DELMODE_FIXED;
2353 	icrlo |= APIC_DESTMODE_PHY | APIC_TRIGMOD_EDGE | APIC_LEVEL_ASSERT;
2354 
2355 	/* Wait for an earlier IPI to finish. */
2356 	if (!lapic_ipi_wait(lapic_ds_idle_timeout)) {
2357 		if (KERNEL_PANICKED())
2358 			return;
2359 		else
2360 			panic("APIC: Previous IPI is stuck");
2361 	}
2362 
2363 	lapic_ipi_raw(icrlo, destfield);
2364 
2365 #ifdef DETECT_DEADLOCK
2366 	/* Wait for IPI to be delivered. */
2367 	if (!lapic_ipi_wait(AFTER_SPIN)) {
2368 #ifdef needsattention
2369 		/*
2370 		 * XXX FIXME:
2371 		 *
2372 		 * The above function waits for the message to actually be
2373 		 * delivered.  It breaks out after an arbitrary timeout
2374 		 * since the message should eventually be delivered (at
2375 		 * least in theory) and that if it wasn't we would catch
2376 		 * the failure with the check above when the next IPI is
2377 		 * sent.
2378 		 *
2379 		 * We could skip this wait entirely, EXCEPT it probably
2380 		 * protects us from other routines that assume that the
2381 		 * message was delivered and acted upon when this function
2382 		 * returns.
2383 		 */
2384 		printf("APIC: IPI might be stuck\n");
2385 #else /* !needsattention */
2386 		/* Wait until mesage is sent without a timeout. */
2387 		while (lapic_read_icr_lo() & APIC_DELSTAT_PEND)
2388 			ia32_pause();
2389 #endif /* needsattention */
2390 	}
2391 #endif /* DETECT_DEADLOCK */
2392 }
2393 
2394 void (*ipi_vectored)(u_int, int) = &native_lapic_ipi_vectored;
2395 #endif /* SMP */
2396 
2397 void (*fred_ipi_handlers[IPI_DYN_LAST - IPI_DYN_FIRST + 1])(struct trapframe *);
2398 
2399 /*
2400  * Since the IDT is shared by all CPUs the IPI slot update needs to be globally
2401  * visible.
2402  *
2403  * Consider the case where an IPI is generated immediately after allocation:
2404  *     vector = lapic_ipi_alloc(ipifunc);
2405  *     ipi_selected(other_cpus, vector);
2406  *
2407  * In xAPIC mode a write to ICR_LO has serializing semantics because the
2408  * APIC page is mapped as an uncached region. In x2APIC mode there is an
2409  * explicit 'mfence' before the ICR MSR is written. Therefore in both cases
2410  * the IDT slot update is globally visible before the IPI is delivered.
2411  */
2412 int
lapic_ipi_alloc(inthand_t * ipifunc,void (* fred_ipifunc)(struct trapframe *))2413 lapic_ipi_alloc(inthand_t *ipifunc, void (*fred_ipifunc)(struct trapframe *))
2414 {
2415 	void (*fip)(struct trapframe *);
2416 	int idx, vector;
2417 
2418 	KASSERT(ipifunc != &IDTVEC(rsvd) && ipifunc != &IDTVEC(rsvd_pti),
2419 	    ("invalid ipifunc %p", ipifunc));
2420 
2421 	vector = -1;
2422 	mtx_lock_spin(&icu_lock);
2423 	for (idx = IPI_DYN_FIRST; idx <= IPI_DYN_LAST; idx++) {
2424 		fip = fred_ipi_handlers[idx - IPI_DYN_FIRST];
2425 		if (fip == NULL) {
2426 			vector = idx;
2427 			fred_ipi_handlers[idx - IPI_DYN_FIRST] = fred_ipifunc;
2428 			setidt(vector, ipifunc, SDT_APIC, SEL_KPL, GSEL_APIC);
2429 			break;
2430 		}
2431 	}
2432 	mtx_unlock_spin(&icu_lock);
2433 	return (vector);
2434 }
2435 
2436 void
lapic_ipi_free(int vector)2437 lapic_ipi_free(int vector)
2438 {
2439 	struct gate_descriptor *ip;
2440 	long func __diagused;
2441 
2442 	KASSERT(vector >= IPI_DYN_FIRST && vector <= IPI_DYN_LAST,
2443 	    ("%s: invalid vector %d", __func__, vector));
2444 
2445 	mtx_lock_spin(&icu_lock);
2446 	KASSERT(fred_ipi_handlers[vector - IPI_DYN_FIRST] != NULL,
2447 	    ("NULL fred func %d", vector));
2448 	fred_ipi_handlers[vector - IPI_DYN_FIRST] = NULL;
2449 	if (!fred) {
2450 		ip = &idt[vector];
2451 		func = (ip->gd_hioffset << 16) | ip->gd_looffset;
2452 #ifdef __i386__
2453 		func -= setidt_disp;
2454 #endif
2455 		KASSERT(func != (uintptr_t)&IDTVEC(rsvd) &&
2456 		    func != (uintptr_t)&IDTVEC(rsvd_pti),
2457 		    ("invalid idtfunc %d %#lx", vector, func));
2458 		setidt(vector, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd),
2459 		    SDT_APIC, SEL_KPL, GSEL_APIC);
2460 	}
2461 	mtx_unlock_spin(&icu_lock);
2462 }
2463