local_apic.c revision 140254
1/*-
2 * Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org>
3 * Copyright (c) 1996, by Steve Passe
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. The name of the developer may NOT be used to endorse or promote products
12 *    derived from this software without specific prior written permission.
13 * 3. Neither the name of the author nor the names of any co-contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30/*
31 * Local APIC support on Pentium and later processors.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD: head/sys/i386/i386/local_apic.c 140254 2005-01-14 18:31:00Z jhb $");
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/bus.h>
40#include <sys/kernel.h>
41#include <sys/pcpu.h>
42
43#include <vm/vm.h>
44#include <vm/pmap.h>
45
46#include <machine/apicreg.h>
47#include <machine/cputypes.h>
48#include <machine/frame.h>
49#include <machine/intr_machdep.h>
50#include <machine/apicvar.h>
51#include <machine/md_var.h>
52#include <machine/smp.h>
53#include <machine/specialreg.h>
54
55/*
56 * We can handle up to 60 APICs via our logical cluster IDs, but currently
57 * the physical IDs on Intel processors up to the Pentium 4 are limited to
58 * 16.
59 */
60#define	MAX_APICID	16
61
62/* Sanity checks on IDT vectors. */
63CTASSERT(APIC_IO_INTS + APIC_NUM_IOINTS == APIC_TIMER_INT);
64CTASSERT(APIC_TIMER_INT < APIC_LOCAL_INTS);
65CTASSERT(APIC_LOCAL_INTS == 240);
66CTASSERT(IPI_STOP < APIC_SPURIOUS_INT);
67
68/*
69 * Support for local APICs.  Local APICs manage interrupts on each
70 * individual processor as opposed to I/O APICs which receive interrupts
71 * from I/O devices and then forward them on to the local APICs.
72 *
73 * Local APICs can also send interrupts to each other thus providing the
74 * mechanism for IPIs.
75 */
76
77struct lvt {
78	u_int lvt_edgetrigger:1;
79	u_int lvt_activehi:1;
80	u_int lvt_masked:1;
81	u_int lvt_active:1;
82	u_int lvt_mode:16;
83	u_int lvt_vector:8;
84};
85
86struct lapic {
87	struct lvt la_lvts[LVT_MAX + 1];
88	u_int la_id:8;
89	u_int la_cluster:4;
90	u_int la_cluster_id:2;
91	u_int la_present:1;
92} static lapics[MAX_APICID];
93
94/* XXX: should thermal be an NMI? */
95
96/* Global defaults for local APIC LVT entries. */
97static struct lvt lvts[LVT_MAX + 1] = {
98	{ 1, 1, 1, 1, APIC_LVT_DM_EXTINT, 0 },	/* LINT0: masked ExtINT */
99	{ 1, 1, 0, 1, APIC_LVT_DM_NMI, 0 },	/* LINT1: NMI */
100	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_TIMER_INT },	/* Timer */
101	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_ERROR_INT },	/* Error */
102	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, 0 },	/* PMC */
103	{ 1, 1, 1, 1, APIC_LVT_DM_FIXED, APIC_THERMAL_INT },	/* Thermal */
104};
105
106static inthand_t *ioint_handlers[] = {
107	NULL,			/* 0 - 31 */
108	IDTVEC(apic_isr1),	/* 32 - 63 */
109	IDTVEC(apic_isr2),	/* 64 - 95 */
110	IDTVEC(apic_isr3),	/* 96 - 127 */
111	IDTVEC(apic_isr4),	/* 128 - 159 */
112	IDTVEC(apic_isr5),	/* 160 - 191 */
113	IDTVEC(apic_isr6),	/* 192 - 223 */
114	IDTVEC(apic_isr7),	/* 224 - 255 */
115};
116
117volatile lapic_t *lapic;
118
119static void	lapic_enable(void);
120static uint32_t	lvt_mode(struct lapic *la, u_int pin, uint32_t value);
121
122static uint32_t
123lvt_mode(struct lapic *la, u_int pin, uint32_t value)
124{
125	struct lvt *lvt;
126
127	KASSERT(pin <= LVT_MAX, ("%s: pin %u out of range", __func__, pin));
128	if (la->la_lvts[pin].lvt_active)
129		lvt = &la->la_lvts[pin];
130	else
131		lvt = &lvts[pin];
132
133	value &= ~(APIC_LVT_M | APIC_LVT_TM | APIC_LVT_IIPP | APIC_LVT_DM |
134	    APIC_LVT_VECTOR);
135	if (lvt->lvt_edgetrigger == 0)
136		value |= APIC_LVT_TM;
137	if (lvt->lvt_activehi == 0)
138		value |= APIC_LVT_IIPP_INTALO;
139	if (lvt->lvt_masked)
140		value |= APIC_LVT_M;
141	value |= lvt->lvt_mode;
142	switch (lvt->lvt_mode) {
143	case APIC_LVT_DM_NMI:
144	case APIC_LVT_DM_SMI:
145	case APIC_LVT_DM_INIT:
146	case APIC_LVT_DM_EXTINT:
147		if (!lvt->lvt_edgetrigger) {
148			printf("lapic%u: Forcing LINT%u to edge trigger\n",
149			    la->la_id, pin);
150			value |= APIC_LVT_TM;
151		}
152		/* Use a vector of 0. */
153		break;
154	case APIC_LVT_DM_FIXED:
155		value |= lvt->lvt_vector;
156		break;
157	default:
158		panic("bad APIC LVT delivery mode: %#x\n", value);
159	}
160	return (value);
161}
162
163/*
164 * Map the local APIC and setup necessary interrupt vectors.
165 */
166void
167lapic_init(uintptr_t addr)
168{
169
170	/* Map the local APIC and setup the spurious interrupt handler. */
171	KASSERT(trunc_page(addr) == addr,
172	    ("local APIC not aligned on a page boundary"));
173	lapic = (lapic_t *)pmap_mapdev(addr, sizeof(lapic_t));
174	setidt(APIC_SPURIOUS_INT, IDTVEC(spuriousint), SDT_SYS386IGT, SEL_KPL,
175	    GSEL(GCODE_SEL, SEL_KPL));
176
177	/* Perform basic initialization of the BSP's local APIC. */
178	lapic_enable();
179
180	/* Set BSP's per-CPU local APIC ID. */
181	PCPU_SET(apic_id, lapic_id());
182
183	/* XXX: timer/error/thermal interrupts */
184}
185
186/*
187 * Create a local APIC instance.
188 */
189void
190lapic_create(u_int apic_id, int boot_cpu)
191{
192	int i;
193
194	if (apic_id >= MAX_APICID) {
195		printf("APIC: Ignoring local APIC with ID %d\n", apic_id);
196		if (boot_cpu)
197			panic("Can't ignore BSP");
198		return;
199	}
200	KASSERT(!lapics[apic_id].la_present, ("duplicate local APIC %u",
201	    apic_id));
202
203	/*
204	 * Assume no local LVT overrides and a cluster of 0 and
205	 * intra-cluster ID of 0.
206	 */
207	lapics[apic_id].la_present = 1;
208	lapics[apic_id].la_id = apic_id;
209	for (i = 0; i < LVT_MAX; i++) {
210		lapics[apic_id].la_lvts[i] = lvts[i];
211		lapics[apic_id].la_lvts[i].lvt_active = 0;
212	}
213
214#ifdef SMP
215	cpu_add(apic_id, boot_cpu);
216#endif
217}
218
219/*
220 * Dump contents of local APIC registers
221 */
222void
223lapic_dump(const char* str)
224{
225
226	printf("cpu%d %s:\n", PCPU_GET(cpuid), str);
227	printf("     ID: 0x%08x   VER: 0x%08x LDR: 0x%08x DFR: 0x%08x\n",
228	    lapic->id, lapic->version, lapic->ldr, lapic->dfr);
229	printf("  lint0: 0x%08x lint1: 0x%08x TPR: 0x%08x SVR: 0x%08x\n",
230	    lapic->lvt_lint0, lapic->lvt_lint1, lapic->tpr, lapic->svr);
231	printf("  timer: 0x%08x therm: 0x%08x err: 0x%08x pcm: 0x%08x\n",
232	    lapic->lvt_timer, lapic->lvt_thermal, lapic->lvt_error,
233	    lapic->lvt_pcint);
234}
235
236void
237lapic_enable_intr(u_int irq)
238{
239	u_int vector;
240
241	vector = apic_irq_to_idt(irq);
242	KASSERT(vector != IDT_SYSCALL, ("Attempt to overwrite syscall entry"));
243	KASSERT(ioint_handlers[vector / 32] != NULL,
244	    ("No ISR handler for IRQ %u", irq));
245	setidt(vector, ioint_handlers[vector / 32], SDT_SYS386IGT, SEL_KPL,
246	    GSEL(GCODE_SEL, SEL_KPL));
247}
248
249void
250lapic_setup(void)
251{
252	struct lapic *la;
253	u_int32_t value, maxlvt;
254	register_t eflags;
255
256	la = &lapics[lapic_id()];
257	KASSERT(la->la_present, ("missing APIC structure"));
258	eflags = intr_disable();
259	maxlvt = (lapic->version & APIC_VER_MAXLVT) >> MAXLVTSHIFT;
260
261	/* Initialize the TPR to allow all interrupts. */
262	lapic_set_tpr(0);
263
264	/* Use the cluster model for logical IDs. */
265	value = lapic->dfr;
266	value &= ~APIC_DFR_MODEL_MASK;
267	value |= APIC_DFR_MODEL_CLUSTER;
268	lapic->dfr = value;
269
270	/* Set this APIC's logical ID. */
271	value = lapic->ldr;
272	value &= ~APIC_ID_MASK;
273	value |= (la->la_cluster << APIC_ID_CLUSTER_SHIFT |
274	    1 << la->la_cluster_id) << APIC_ID_SHIFT;
275	lapic->ldr = value;
276
277	/* Setup spurious vector and enable the local APIC. */
278	lapic_enable();
279
280	/* Program LINT[01] LVT entries. */
281	lapic->lvt_lint0 = lvt_mode(la, LVT_LINT0, lapic->lvt_lint0);
282	lapic->lvt_lint1 = lvt_mode(la, LVT_LINT1, lapic->lvt_lint1);
283
284	/* XXX: more LVT entries */
285
286	intr_restore(eflags);
287}
288
289void
290lapic_disable(void)
291{
292	uint32_t value;
293
294	/* Software disable the local APIC. */
295	value = lapic->svr;
296	value &= ~APIC_SVR_SWEN;
297	lapic->svr = value;
298}
299
300static void
301lapic_enable(void)
302{
303	u_int32_t value;
304
305	/* Program the spurious vector to enable the local APIC. */
306	value = lapic->svr;
307	value &= ~(APIC_SVR_VECTOR | APIC_SVR_FOCUS);
308	value |= (APIC_SVR_FEN | APIC_SVR_SWEN | APIC_SPURIOUS_INT);
309	lapic->svr = value;
310}
311
312int
313lapic_id(void)
314{
315
316	KASSERT(lapic != NULL, ("local APIC is not mapped"));
317	return (lapic->id >> APIC_ID_SHIFT);
318}
319
320int
321lapic_intr_pending(u_int vector)
322{
323	volatile u_int32_t *irr;
324
325	/*
326	 * The IRR registers are an array of 128-bit registers each of
327	 * which only describes 32 interrupts in the low 32 bits..  Thus,
328	 * we divide the vector by 32 to get the 128-bit index.  We then
329	 * multiply that index by 4 to get the equivalent index from
330	 * treating the IRR as an array of 32-bit registers.  Finally, we
331	 * modulus the vector by 32 to determine the individual bit to
332	 * test.
333	 */
334	irr = &lapic->irr0;
335	return (irr[(vector / 32) * 4] & 1 << (vector % 32));
336}
337
338void
339lapic_set_logical_id(u_int apic_id, u_int cluster, u_int cluster_id)
340{
341	struct lapic *la;
342
343	KASSERT(lapics[apic_id].la_present, ("%s: APIC %u doesn't exist",
344	    __func__, apic_id));
345	KASSERT(cluster <= APIC_MAX_CLUSTER, ("%s: cluster %u too big",
346	    __func__, cluster));
347	KASSERT(cluster_id <= APIC_MAX_INTRACLUSTER_ID,
348	    ("%s: intra cluster id %u too big", __func__, cluster_id));
349	la = &lapics[apic_id];
350	la->la_cluster = cluster;
351	la->la_cluster_id = cluster_id;
352}
353
354int
355lapic_set_lvt_mask(u_int apic_id, u_int pin, u_char masked)
356{
357
358	if (pin > LVT_MAX)
359		return (EINVAL);
360	if (apic_id == APIC_ID_ALL) {
361		lvts[pin].lvt_masked = masked;
362		if (bootverbose)
363			printf("lapic:");
364	} else {
365		KASSERT(lapics[apic_id].la_present,
366		    ("%s: missing APIC %u", __func__, apic_id));
367		lapics[apic_id].la_lvts[pin].lvt_masked = masked;
368		lapics[apic_id].la_lvts[pin].lvt_active = 1;
369		if (bootverbose)
370			printf("lapic%u:", apic_id);
371	}
372	if (bootverbose)
373		printf(" LINT%u %s\n", pin, masked ? "masked" : "unmasked");
374	return (0);
375}
376
377int
378lapic_set_lvt_mode(u_int apic_id, u_int pin, u_int32_t mode)
379{
380	struct lvt *lvt;
381
382	if (pin > LVT_MAX)
383		return (EINVAL);
384	if (apic_id == APIC_ID_ALL) {
385		lvt = &lvts[pin];
386		if (bootverbose)
387			printf("lapic:");
388	} else {
389		KASSERT(lapics[apic_id].la_present,
390		    ("%s: missing APIC %u", __func__, apic_id));
391		lvt = &lapics[apic_id].la_lvts[pin];
392		lvt->lvt_active = 1;
393		if (bootverbose)
394			printf("lapic%u:", apic_id);
395	}
396	lvt->lvt_mode = mode;
397	switch (mode) {
398	case APIC_LVT_DM_NMI:
399	case APIC_LVT_DM_SMI:
400	case APIC_LVT_DM_INIT:
401	case APIC_LVT_DM_EXTINT:
402		lvt->lvt_edgetrigger = 1;
403		lvt->lvt_activehi = 1;
404		if (mode == APIC_LVT_DM_EXTINT)
405			lvt->lvt_masked = 1;
406		else
407			lvt->lvt_masked = 0;
408		break;
409	default:
410		panic("Unsupported delivery mode: 0x%x\n", mode);
411	}
412	if (bootverbose) {
413		printf(" Routing ");
414		switch (mode) {
415		case APIC_LVT_DM_NMI:
416			printf("NMI");
417			break;
418		case APIC_LVT_DM_SMI:
419			printf("SMI");
420			break;
421		case APIC_LVT_DM_INIT:
422			printf("INIT");
423			break;
424		case APIC_LVT_DM_EXTINT:
425			printf("ExtINT");
426			break;
427		}
428		printf(" -> LINT%u\n", pin);
429	}
430	return (0);
431}
432
433int
434lapic_set_lvt_polarity(u_int apic_id, u_int pin, enum intr_polarity pol)
435{
436
437	if (pin > LVT_MAX || pol == INTR_POLARITY_CONFORM)
438		return (EINVAL);
439	if (apic_id == APIC_ID_ALL) {
440		lvts[pin].lvt_activehi = (pol == INTR_POLARITY_HIGH);
441		if (bootverbose)
442			printf("lapic:");
443	} else {
444		KASSERT(lapics[apic_id].la_present,
445		    ("%s: missing APIC %u", __func__, apic_id));
446		lapics[apic_id].la_lvts[pin].lvt_active = 1;
447		lapics[apic_id].la_lvts[pin].lvt_activehi =
448		    (pol == INTR_POLARITY_HIGH);
449		if (bootverbose)
450			printf("lapic%u:", apic_id);
451	}
452	if (bootverbose)
453		printf(" LINT%u polarity: %s\n", pin,
454		    pol == INTR_POLARITY_HIGH ? "high" : "low");
455	return (0);
456}
457
458int
459lapic_set_lvt_triggermode(u_int apic_id, u_int pin, enum intr_trigger trigger)
460{
461
462	if (pin > LVT_MAX || trigger == INTR_TRIGGER_CONFORM)
463		return (EINVAL);
464	if (apic_id == APIC_ID_ALL) {
465		lvts[pin].lvt_edgetrigger = (trigger == INTR_TRIGGER_EDGE);
466		if (bootverbose)
467			printf("lapic:");
468	} else {
469		KASSERT(lapics[apic_id].la_present,
470		    ("%s: missing APIC %u", __func__, apic_id));
471		lapics[apic_id].la_lvts[pin].lvt_edgetrigger =
472		    (trigger == INTR_TRIGGER_EDGE);
473		lapics[apic_id].la_lvts[pin].lvt_active = 1;
474		if (bootverbose)
475			printf("lapic%u:", apic_id);
476	}
477	if (bootverbose)
478		printf(" LINT%u trigger: %s\n", pin,
479		    trigger == INTR_TRIGGER_EDGE ? "edge" : "level");
480	return (0);
481}
482
483/*
484 * Adjust the TPR of the current CPU so that it blocks all interrupts below
485 * the passed in vector.
486 */
487void
488lapic_set_tpr(u_int vector)
489{
490#ifdef CHEAP_TPR
491	lapic->tpr = vector;
492#else
493	u_int32_t tpr;
494
495	tpr = lapic->tpr & ~APIC_TPR_PRIO;
496	tpr |= vector;
497	lapic->tpr = tpr;
498#endif
499}
500
501void
502lapic_eoi(void)
503{
504
505	lapic->eoi = 0;
506}
507
508void
509lapic_handle_intr(struct intrframe frame)
510{
511	struct intsrc *isrc;
512
513	if (frame.if_vec == -1)
514		panic("Couldn't get vector from ISR!");
515	isrc = intr_lookup_source(apic_idt_to_irq(frame.if_vec));
516	intr_execute_handlers(isrc, &frame);
517}
518
519/* Translate between IDT vectors and IRQ vectors. */
520u_int
521apic_irq_to_idt(u_int irq)
522{
523	u_int vector;
524
525	KASSERT(irq < NUM_IO_INTS, ("Invalid IRQ %u", irq));
526	vector = irq + APIC_IO_INTS;
527	if (vector >= IDT_SYSCALL)
528		vector++;
529	return (vector);
530}
531
532u_int
533apic_idt_to_irq(u_int vector)
534{
535
536	KASSERT(vector >= APIC_IO_INTS && vector != IDT_SYSCALL &&
537	    vector <= APIC_IO_INTS + NUM_IO_INTS,
538	    ("Vector %u does not map to an IRQ line", vector));
539	if (vector > IDT_SYSCALL)
540		vector--;
541	return (vector - APIC_IO_INTS);
542}
543
544/*
545 * APIC probing support code.  This includes code to manage enumerators.
546 */
547
548static SLIST_HEAD(, apic_enumerator) enumerators =
549	SLIST_HEAD_INITIALIZER(enumerators);
550static struct apic_enumerator *best_enum;
551
552void
553apic_register_enumerator(struct apic_enumerator *enumerator)
554{
555#ifdef INVARIANTS
556	struct apic_enumerator *apic_enum;
557
558	SLIST_FOREACH(apic_enum, &enumerators, apic_next) {
559		if (apic_enum == enumerator)
560			panic("%s: Duplicate register of %s", __func__,
561			    enumerator->apic_name);
562	}
563#endif
564	SLIST_INSERT_HEAD(&enumerators, enumerator, apic_next);
565}
566
567/*
568 * Probe the APIC enumerators, enumerate CPUs, and initialize the
569 * local APIC.
570 */
571static void
572apic_init(void *dummy __unused)
573{
574	struct apic_enumerator *enumerator;
575	uint64_t apic_base;
576	int retval, best;
577
578	/* We only support built in local APICs. */
579	if (!(cpu_feature & CPUID_APIC))
580		return;
581
582	/* Don't probe if APIC mode is disabled. */
583	if (resource_disabled("apic", 0))
584		return;
585
586	/* First, probe all the enumerators to find the best match. */
587	best_enum = NULL;
588	best = 0;
589	SLIST_FOREACH(enumerator, &enumerators, apic_next) {
590		retval = enumerator->apic_probe();
591		if (retval > 0)
592			continue;
593		if (best_enum == NULL || best < retval) {
594			best_enum = enumerator;
595			best = retval;
596		}
597	}
598	if (best_enum == NULL) {
599		if (bootverbose)
600			printf("APIC: Could not find any APICs.\n");
601		return;
602	}
603
604	if (bootverbose)
605		printf("APIC: Using the %s enumerator.\n",
606		    best_enum->apic_name);
607
608	/*
609	 * To work around an errata, we disable the local APIC on some
610	 * CPUs during early startup.  We need to turn the local APIC back
611	 * on on such CPUs now.
612	 */
613	if (cpu == CPU_686 && strcmp(cpu_vendor, "GenuineIntel") == 0 &&
614	    (cpu_id & 0xff0) == 0x610) {
615		apic_base = rdmsr(MSR_APICBASE);
616		apic_base |= APICBASE_ENABLED;
617		wrmsr(MSR_APICBASE, apic_base);
618	}
619
620	/* Second, probe the CPU's in the system. */
621	retval = best_enum->apic_probe_cpus();
622	if (retval != 0)
623		printf("%s: Failed to probe CPUs: returned %d\n",
624		    best_enum->apic_name, retval);
625
626	/* Third, initialize the local APIC. */
627	retval = best_enum->apic_setup_local();
628	if (retval != 0)
629		printf("%s: Failed to setup the local APIC: returned %d\n",
630		    best_enum->apic_name, retval);
631#ifdef SMP
632	/* Last, setup the cpu topology now that we have probed CPUs */
633	mp_topology();
634#endif
635}
636SYSINIT(apic_init, SI_SUB_CPU, SI_ORDER_FIRST, apic_init, NULL)
637
638/*
639 * Setup the I/O APICs.
640 */
641static void
642apic_setup_io(void *dummy __unused)
643{
644	int retval;
645
646	if (best_enum == NULL)
647		return;
648	retval = best_enum->apic_setup_io();
649	if (retval != 0)
650		printf("%s: Failed to setup I/O APICs: returned %d\n",
651		    best_enum->apic_name, retval);
652
653	/*
654	 * Finish setting up the local APIC on the BSP once we know how to
655	 * properly program the LINT pins.
656	 */
657	lapic_setup();
658	if (bootverbose)
659		lapic_dump("BSP");
660}
661SYSINIT(apic_setup_io, SI_SUB_INTR, SI_ORDER_SECOND, apic_setup_io, NULL)
662
663#ifdef SMP
664/*
665 * Inter Processor Interrupt functions.  The lapic_ipi_*() functions are
666 * private to the sys/i386 code.  The public interface for the rest of the
667 * kernel is defined in mp_machdep.c.
668 */
669int
670lapic_ipi_wait(int delay)
671{
672	int x, incr;
673
674	/*
675	 * Wait delay loops for IPI to be sent.  This is highly bogus
676	 * since this is sensitive to CPU clock speed.  If delay is
677	 * -1, we wait forever.
678	 */
679	if (delay == -1) {
680		incr = 0;
681		delay = 1;
682	} else
683		incr = 1;
684	for (x = 0; x < delay; x += incr) {
685		if ((lapic->icr_lo & APIC_DELSTAT_MASK) == APIC_DELSTAT_IDLE)
686			return (1);
687		ia32_pause();
688	}
689	return (0);
690}
691
692void
693lapic_ipi_raw(register_t icrlo, u_int dest)
694{
695	register_t value, eflags;
696
697	/* XXX: Need more sanity checking of icrlo? */
698	KASSERT(lapic != NULL, ("%s called too early", __func__));
699	KASSERT((dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
700	    ("%s: invalid dest field", __func__));
701	KASSERT((icrlo & APIC_ICRLO_RESV_MASK) == 0,
702	    ("%s: reserved bits set in ICR LO register", __func__));
703
704	/* Set destination in ICR HI register if it is being used. */
705	eflags = intr_disable();
706	if ((icrlo & APIC_DEST_MASK) == APIC_DEST_DESTFLD) {
707		value = lapic->icr_hi;
708		value &= ~APIC_ID_MASK;
709		value |= dest << APIC_ID_SHIFT;
710		lapic->icr_hi = value;
711	}
712
713	/* Program the contents of the IPI and dispatch it. */
714	value = lapic->icr_lo;
715	value &= APIC_ICRLO_RESV_MASK;
716	value |= icrlo;
717	lapic->icr_lo = value;
718	intr_restore(eflags);
719}
720
721#define	BEFORE_SPIN	1000000
722#ifdef DETECT_DEADLOCK
723#define	AFTER_SPIN	1000
724#endif
725
726void
727lapic_ipi_vectored(u_int vector, int dest)
728{
729	register_t icrlo, destfield;
730
731	KASSERT((vector & ~APIC_VECTOR_MASK) == 0,
732	    ("%s: invalid vector %d", __func__, vector));
733
734	icrlo = vector | APIC_DELMODE_FIXED | APIC_DESTMODE_PHY |
735	    APIC_LEVEL_DEASSERT | APIC_TRIGMOD_EDGE;
736	destfield = 0;
737	switch (dest) {
738	case APIC_IPI_DEST_SELF:
739		icrlo |= APIC_DEST_SELF;
740		break;
741	case APIC_IPI_DEST_ALL:
742		icrlo |= APIC_DEST_ALLISELF;
743		break;
744	case APIC_IPI_DEST_OTHERS:
745		icrlo |= APIC_DEST_ALLESELF;
746		break;
747	default:
748		KASSERT((dest & ~(APIC_ID_MASK >> APIC_ID_SHIFT)) == 0,
749		    ("%s: invalid destination 0x%x", __func__, dest));
750		destfield = dest;
751	}
752
753	/* Wait for an earlier IPI to finish. */
754	if (!lapic_ipi_wait(BEFORE_SPIN))
755		panic("APIC: Previous IPI is stuck");
756
757	lapic_ipi_raw(icrlo, destfield);
758
759#ifdef DETECT_DEADLOCK
760	/* Wait for IPI to be delivered. */
761	if (!lapic_ipi_wait(AFTER_SPIN)) {
762#ifdef needsattention
763		/*
764		 * XXX FIXME:
765		 *
766		 * The above function waits for the message to actually be
767		 * delivered.  It breaks out after an arbitrary timeout
768		 * since the message should eventually be delivered (at
769		 * least in theory) and that if it wasn't we would catch
770		 * the failure with the check above when the next IPI is
771		 * sent.
772		 *
773		 * We could skip this wait entirely, EXCEPT it probably
774		 * protects us from other routines that assume that the
775		 * message was delivered and acted upon when this function
776		 * returns.
777		 */
778		printf("APIC: IPI might be stuck\n");
779#else /* !needsattention */
780		/* Wait until mesage is sent without a timeout. */
781		while (lapic->icr_lo & APIC_DELSTAT_PEND)
782			ia32_pause();
783#endif /* needsattention */
784	}
785#endif /* DETECT_DEADLOCK */
786}
787#endif /* SMP */
788