xref: /linux/arch/x86/kernel/apic/apic.c (revision 092e0e7e520a1fca03e13c9f2d157432a8657ff2)
1 /*
2  *	Local APIC handling, local APIC timers
3  *
4  *	(c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
5  *
6  *	Fixes
7  *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
8  *					thanks to Eric Gilmore
9  *					and Rolf G. Tews
10  *					for testing these extensively.
11  *	Maciej W. Rozycki	:	Various updates and fixes.
12  *	Mikael Pettersson	:	Power Management for UP-APIC.
13  *	Pavel Machek and
14  *	Mikael Pettersson	:	PM converted to driver model.
15  */
16 
17 #include <linux/perf_event.h>
18 #include <linux/kernel_stat.h>
19 #include <linux/mc146818rtc.h>
20 #include <linux/acpi_pmtmr.h>
21 #include <linux/clockchips.h>
22 #include <linux/interrupt.h>
23 #include <linux/bootmem.h>
24 #include <linux/ftrace.h>
25 #include <linux/ioport.h>
26 #include <linux/module.h>
27 #include <linux/sysdev.h>
28 #include <linux/delay.h>
29 #include <linux/timex.h>
30 #include <linux/dmar.h>
31 #include <linux/init.h>
32 #include <linux/cpu.h>
33 #include <linux/dmi.h>
34 #include <linux/nmi.h>
35 #include <linux/smp.h>
36 #include <linux/mm.h>
37 
38 #include <asm/perf_event.h>
39 #include <asm/x86_init.h>
40 #include <asm/pgalloc.h>
41 #include <asm/atomic.h>
42 #include <asm/mpspec.h>
43 #include <asm/i8253.h>
44 #include <asm/i8259.h>
45 #include <asm/proto.h>
46 #include <asm/apic.h>
47 #include <asm/desc.h>
48 #include <asm/hpet.h>
49 #include <asm/idle.h>
50 #include <asm/mtrr.h>
51 #include <asm/smp.h>
52 #include <asm/mce.h>
53 #include <asm/kvm_para.h>
54 #include <asm/tsc.h>
55 #include <asm/atomic.h>
56 
57 unsigned int num_processors;
58 
59 unsigned disabled_cpus __cpuinitdata;
60 
61 /* Processor that is doing the boot up */
62 unsigned int boot_cpu_physical_apicid = -1U;
63 
64 /*
65  * The highest APIC ID seen during enumeration.
66  */
67 unsigned int max_physical_apicid;
68 
69 /*
70  * Bitmask of physically existing CPUs:
71  */
72 physid_mask_t phys_cpu_present_map;
73 
74 /*
75  * Map cpu index to physical APIC ID
76  */
77 DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
78 DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
79 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
80 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
81 
82 #ifdef CONFIG_X86_32
83 /*
84  * Knob to control our willingness to enable the local APIC.
85  *
86  * +1=force-enable
87  */
88 static int force_enable_local_apic;
89 /*
90  * APIC command line parameters
91  */
92 static int __init parse_lapic(char *arg)
93 {
94 	force_enable_local_apic = 1;
95 	return 0;
96 }
97 early_param("lapic", parse_lapic);
98 /* Local APIC was disabled by the BIOS and enabled by the kernel */
99 static int enabled_via_apicbase;
100 
101 /*
102  * Handle interrupt mode configuration register (IMCR).
103  * This register controls whether the interrupt signals
104  * that reach the BSP come from the master PIC or from the
105  * local APIC. Before entering Symmetric I/O Mode, either
106  * the BIOS or the operating system must switch out of
107  * PIC Mode by changing the IMCR.
108  */
109 static inline void imcr_pic_to_apic(void)
110 {
111 	/* select IMCR register */
112 	outb(0x70, 0x22);
113 	/* NMI and 8259 INTR go through APIC */
114 	outb(0x01, 0x23);
115 }
116 
117 static inline void imcr_apic_to_pic(void)
118 {
119 	/* select IMCR register */
120 	outb(0x70, 0x22);
121 	/* NMI and 8259 INTR go directly to BSP */
122 	outb(0x00, 0x23);
123 }
124 #endif
125 
126 #ifdef CONFIG_X86_64
127 static int apic_calibrate_pmtmr __initdata;
128 static __init int setup_apicpmtimer(char *s)
129 {
130 	apic_calibrate_pmtmr = 1;
131 	notsc_setup(NULL);
132 	return 0;
133 }
134 __setup("apicpmtimer", setup_apicpmtimer);
135 #endif
136 
137 int x2apic_mode;
138 #ifdef CONFIG_X86_X2APIC
139 /* x2apic enabled before OS handover */
140 static int x2apic_preenabled;
141 static __init int setup_nox2apic(char *str)
142 {
143 	if (x2apic_enabled()) {
144 		pr_warning("Bios already enabled x2apic, "
145 			   "can't enforce nox2apic");
146 		return 0;
147 	}
148 
149 	setup_clear_cpu_cap(X86_FEATURE_X2APIC);
150 	return 0;
151 }
152 early_param("nox2apic", setup_nox2apic);
153 #endif
154 
155 unsigned long mp_lapic_addr;
156 int disable_apic;
157 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
158 static int disable_apic_timer __cpuinitdata;
159 /* Local APIC timer works in C2 */
160 int local_apic_timer_c2_ok;
161 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
162 
163 int first_system_vector = 0xfe;
164 
165 /*
166  * Debug level, exported for io_apic.c
167  */
168 unsigned int apic_verbosity;
169 
170 int pic_mode;
171 
172 /* Have we found an MP table */
173 int smp_found_config;
174 
175 static struct resource lapic_resource = {
176 	.name = "Local APIC",
177 	.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
178 };
179 
180 static unsigned int calibration_result;
181 
182 static int lapic_next_event(unsigned long delta,
183 			    struct clock_event_device *evt);
184 static void lapic_timer_setup(enum clock_event_mode mode,
185 			      struct clock_event_device *evt);
186 static void lapic_timer_broadcast(const struct cpumask *mask);
187 static void apic_pm_activate(void);
188 
189 /*
190  * The local apic timer can be used for any function which is CPU local.
191  */
192 static struct clock_event_device lapic_clockevent = {
193 	.name		= "lapic",
194 	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
195 			| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
196 	.shift		= 32,
197 	.set_mode	= lapic_timer_setup,
198 	.set_next_event	= lapic_next_event,
199 	.broadcast	= lapic_timer_broadcast,
200 	.rating		= 100,
201 	.irq		= -1,
202 };
203 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
204 
205 static unsigned long apic_phys;
206 
207 /*
208  * Get the LAPIC version
209  */
210 static inline int lapic_get_version(void)
211 {
212 	return GET_APIC_VERSION(apic_read(APIC_LVR));
213 }
214 
215 /*
216  * Check, if the APIC is integrated or a separate chip
217  */
218 static inline int lapic_is_integrated(void)
219 {
220 #ifdef CONFIG_X86_64
221 	return 1;
222 #else
223 	return APIC_INTEGRATED(lapic_get_version());
224 #endif
225 }
226 
227 /*
228  * Check, whether this is a modern or a first generation APIC
229  */
230 static int modern_apic(void)
231 {
232 	/* AMD systems use old APIC versions, so check the CPU */
233 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
234 	    boot_cpu_data.x86 >= 0xf)
235 		return 1;
236 	return lapic_get_version() >= 0x14;
237 }
238 
239 /*
240  * right after this call apic become NOOP driven
241  * so apic->write/read doesn't do anything
242  */
243 void apic_disable(void)
244 {
245 	pr_info("APIC: switched to apic NOOP\n");
246 	apic = &apic_noop;
247 }
248 
249 void native_apic_wait_icr_idle(void)
250 {
251 	while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
252 		cpu_relax();
253 }
254 
255 u32 native_safe_apic_wait_icr_idle(void)
256 {
257 	u32 send_status;
258 	int timeout;
259 
260 	timeout = 0;
261 	do {
262 		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
263 		if (!send_status)
264 			break;
265 		udelay(100);
266 	} while (timeout++ < 1000);
267 
268 	return send_status;
269 }
270 
271 void native_apic_icr_write(u32 low, u32 id)
272 {
273 	apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
274 	apic_write(APIC_ICR, low);
275 }
276 
277 u64 native_apic_icr_read(void)
278 {
279 	u32 icr1, icr2;
280 
281 	icr2 = apic_read(APIC_ICR2);
282 	icr1 = apic_read(APIC_ICR);
283 
284 	return icr1 | ((u64)icr2 << 32);
285 }
286 
287 /**
288  * enable_NMI_through_LVT0 - enable NMI through local vector table 0
289  */
290 void __cpuinit enable_NMI_through_LVT0(void)
291 {
292 	unsigned int v;
293 
294 	/* unmask and set to NMI */
295 	v = APIC_DM_NMI;
296 
297 	/* Level triggered for 82489DX (32bit mode) */
298 	if (!lapic_is_integrated())
299 		v |= APIC_LVT_LEVEL_TRIGGER;
300 
301 	apic_write(APIC_LVT0, v);
302 }
303 
304 #ifdef CONFIG_X86_32
305 /**
306  * get_physical_broadcast - Get number of physical broadcast IDs
307  */
308 int get_physical_broadcast(void)
309 {
310 	return modern_apic() ? 0xff : 0xf;
311 }
312 #endif
313 
314 /**
315  * lapic_get_maxlvt - get the maximum number of local vector table entries
316  */
317 int lapic_get_maxlvt(void)
318 {
319 	unsigned int v;
320 
321 	v = apic_read(APIC_LVR);
322 	/*
323 	 * - we always have APIC integrated on 64bit mode
324 	 * - 82489DXs do not report # of LVT entries
325 	 */
326 	return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
327 }
328 
329 /*
330  * Local APIC timer
331  */
332 
333 /* Clock divisor */
334 #define APIC_DIVISOR 16
335 
336 /*
337  * This function sets up the local APIC timer, with a timeout of
338  * 'clocks' APIC bus clock. During calibration we actually call
339  * this function twice on the boot CPU, once with a bogus timeout
340  * value, second time for real. The other (noncalibrating) CPUs
341  * call this function only once, with the real, calibrated value.
342  *
343  * We do reads before writes even if unnecessary, to get around the
344  * P5 APIC double write bug.
345  */
346 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
347 {
348 	unsigned int lvtt_value, tmp_value;
349 
350 	lvtt_value = LOCAL_TIMER_VECTOR;
351 	if (!oneshot)
352 		lvtt_value |= APIC_LVT_TIMER_PERIODIC;
353 	if (!lapic_is_integrated())
354 		lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
355 
356 	if (!irqen)
357 		lvtt_value |= APIC_LVT_MASKED;
358 
359 	apic_write(APIC_LVTT, lvtt_value);
360 
361 	/*
362 	 * Divide PICLK by 16
363 	 */
364 	tmp_value = apic_read(APIC_TDCR);
365 	apic_write(APIC_TDCR,
366 		(tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
367 		APIC_TDR_DIV_16);
368 
369 	if (!oneshot)
370 		apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
371 }
372 
373 /*
374  * Setup extended LVT, AMD specific
375  *
376  * Software should use the LVT offsets the BIOS provides.  The offsets
377  * are determined by the subsystems using it like those for MCE
378  * threshold or IBS.  On K8 only offset 0 (APIC500) and MCE interrupts
379  * are supported. Beginning with family 10h at least 4 offsets are
380  * available.
381  *
382  * Since the offsets must be consistent for all cores, we keep track
383  * of the LVT offsets in software and reserve the offset for the same
384  * vector also to be used on other cores. An offset is freed by
385  * setting the entry to APIC_EILVT_MASKED.
386  *
387  * If the BIOS is right, there should be no conflicts. Otherwise a
388  * "[Firmware Bug]: ..." error message is generated. However, if
389  * software does not properly determines the offsets, it is not
390  * necessarily a BIOS bug.
391  */
392 
393 static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
394 
395 static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
396 {
397 	return (old & APIC_EILVT_MASKED)
398 		|| (new == APIC_EILVT_MASKED)
399 		|| ((new & ~APIC_EILVT_MASKED) == old);
400 }
401 
402 static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
403 {
404 	unsigned int rsvd;			/* 0: uninitialized */
405 
406 	if (offset >= APIC_EILVT_NR_MAX)
407 		return ~0;
408 
409 	rsvd = atomic_read(&eilvt_offsets[offset]) & ~APIC_EILVT_MASKED;
410 	do {
411 		if (rsvd &&
412 		    !eilvt_entry_is_changeable(rsvd, new))
413 			/* may not change if vectors are different */
414 			return rsvd;
415 		rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
416 	} while (rsvd != new);
417 
418 	return new;
419 }
420 
421 /*
422  * If mask=1, the LVT entry does not generate interrupts while mask=0
423  * enables the vector. See also the BKDGs.
424  */
425 
426 int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
427 {
428 	unsigned long reg = APIC_EILVTn(offset);
429 	unsigned int new, old, reserved;
430 
431 	new = (mask << 16) | (msg_type << 8) | vector;
432 	old = apic_read(reg);
433 	reserved = reserve_eilvt_offset(offset, new);
434 
435 	if (reserved != new) {
436 		pr_err(FW_BUG "cpu %d, try to setup vector 0x%x, but "
437 		       "vector 0x%x was already reserved by another core, "
438 		       "APIC%lX=0x%x\n",
439 		       smp_processor_id(), new, reserved, reg, old);
440 		return -EINVAL;
441 	}
442 
443 	if (!eilvt_entry_is_changeable(old, new)) {
444 		pr_err(FW_BUG "cpu %d, try to setup vector 0x%x but "
445 		       "register already in use, APIC%lX=0x%x\n",
446 		       smp_processor_id(), new, reg, old);
447 		return -EBUSY;
448 	}
449 
450 	apic_write(reg, new);
451 
452 	return 0;
453 }
454 EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
455 
456 /*
457  * Program the next event, relative to now
458  */
459 static int lapic_next_event(unsigned long delta,
460 			    struct clock_event_device *evt)
461 {
462 	apic_write(APIC_TMICT, delta);
463 	return 0;
464 }
465 
466 /*
467  * Setup the lapic timer in periodic or oneshot mode
468  */
469 static void lapic_timer_setup(enum clock_event_mode mode,
470 			      struct clock_event_device *evt)
471 {
472 	unsigned long flags;
473 	unsigned int v;
474 
475 	/* Lapic used as dummy for broadcast ? */
476 	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
477 		return;
478 
479 	local_irq_save(flags);
480 
481 	switch (mode) {
482 	case CLOCK_EVT_MODE_PERIODIC:
483 	case CLOCK_EVT_MODE_ONESHOT:
484 		__setup_APIC_LVTT(calibration_result,
485 				  mode != CLOCK_EVT_MODE_PERIODIC, 1);
486 		break;
487 	case CLOCK_EVT_MODE_UNUSED:
488 	case CLOCK_EVT_MODE_SHUTDOWN:
489 		v = apic_read(APIC_LVTT);
490 		v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
491 		apic_write(APIC_LVTT, v);
492 		apic_write(APIC_TMICT, 0);
493 		break;
494 	case CLOCK_EVT_MODE_RESUME:
495 		/* Nothing to do here */
496 		break;
497 	}
498 
499 	local_irq_restore(flags);
500 }
501 
502 /*
503  * Local APIC timer broadcast function
504  */
505 static void lapic_timer_broadcast(const struct cpumask *mask)
506 {
507 #ifdef CONFIG_SMP
508 	apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
509 #endif
510 }
511 
512 /*
513  * Setup the local APIC timer for this CPU. Copy the initialized values
514  * of the boot CPU and register the clock event in the framework.
515  */
516 static void __cpuinit setup_APIC_timer(void)
517 {
518 	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
519 
520 	if (cpu_has(&current_cpu_data, X86_FEATURE_ARAT)) {
521 		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
522 		/* Make LAPIC timer preferrable over percpu HPET */
523 		lapic_clockevent.rating = 150;
524 	}
525 
526 	memcpy(levt, &lapic_clockevent, sizeof(*levt));
527 	levt->cpumask = cpumask_of(smp_processor_id());
528 
529 	clockevents_register_device(levt);
530 }
531 
532 /*
533  * In this functions we calibrate APIC bus clocks to the external timer.
534  *
535  * We want to do the calibration only once since we want to have local timer
536  * irqs syncron. CPUs connected by the same APIC bus have the very same bus
537  * frequency.
538  *
539  * This was previously done by reading the PIT/HPET and waiting for a wrap
540  * around to find out, that a tick has elapsed. I have a box, where the PIT
541  * readout is broken, so it never gets out of the wait loop again. This was
542  * also reported by others.
543  *
544  * Monitoring the jiffies value is inaccurate and the clockevents
545  * infrastructure allows us to do a simple substitution of the interrupt
546  * handler.
547  *
548  * The calibration routine also uses the pm_timer when possible, as the PIT
549  * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
550  * back to normal later in the boot process).
551  */
552 
553 #define LAPIC_CAL_LOOPS		(HZ/10)
554 
555 static __initdata int lapic_cal_loops = -1;
556 static __initdata long lapic_cal_t1, lapic_cal_t2;
557 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
558 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
559 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
560 
561 /*
562  * Temporary interrupt handler.
563  */
564 static void __init lapic_cal_handler(struct clock_event_device *dev)
565 {
566 	unsigned long long tsc = 0;
567 	long tapic = apic_read(APIC_TMCCT);
568 	unsigned long pm = acpi_pm_read_early();
569 
570 	if (cpu_has_tsc)
571 		rdtscll(tsc);
572 
573 	switch (lapic_cal_loops++) {
574 	case 0:
575 		lapic_cal_t1 = tapic;
576 		lapic_cal_tsc1 = tsc;
577 		lapic_cal_pm1 = pm;
578 		lapic_cal_j1 = jiffies;
579 		break;
580 
581 	case LAPIC_CAL_LOOPS:
582 		lapic_cal_t2 = tapic;
583 		lapic_cal_tsc2 = tsc;
584 		if (pm < lapic_cal_pm1)
585 			pm += ACPI_PM_OVRRUN;
586 		lapic_cal_pm2 = pm;
587 		lapic_cal_j2 = jiffies;
588 		break;
589 	}
590 }
591 
592 static int __init
593 calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
594 {
595 	const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
596 	const long pm_thresh = pm_100ms / 100;
597 	unsigned long mult;
598 	u64 res;
599 
600 #ifndef CONFIG_X86_PM_TIMER
601 	return -1;
602 #endif
603 
604 	apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
605 
606 	/* Check, if the PM timer is available */
607 	if (!deltapm)
608 		return -1;
609 
610 	mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
611 
612 	if (deltapm > (pm_100ms - pm_thresh) &&
613 	    deltapm < (pm_100ms + pm_thresh)) {
614 		apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
615 		return 0;
616 	}
617 
618 	res = (((u64)deltapm) *  mult) >> 22;
619 	do_div(res, 1000000);
620 	pr_warning("APIC calibration not consistent "
621 		   "with PM-Timer: %ldms instead of 100ms\n",(long)res);
622 
623 	/* Correct the lapic counter value */
624 	res = (((u64)(*delta)) * pm_100ms);
625 	do_div(res, deltapm);
626 	pr_info("APIC delta adjusted to PM-Timer: "
627 		"%lu (%ld)\n", (unsigned long)res, *delta);
628 	*delta = (long)res;
629 
630 	/* Correct the tsc counter value */
631 	if (cpu_has_tsc) {
632 		res = (((u64)(*deltatsc)) * pm_100ms);
633 		do_div(res, deltapm);
634 		apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
635 					  "PM-Timer: %lu (%ld)\n",
636 					(unsigned long)res, *deltatsc);
637 		*deltatsc = (long)res;
638 	}
639 
640 	return 0;
641 }
642 
643 static int __init calibrate_APIC_clock(void)
644 {
645 	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
646 	void (*real_handler)(struct clock_event_device *dev);
647 	unsigned long deltaj;
648 	long delta, deltatsc;
649 	int pm_referenced = 0;
650 
651 	local_irq_disable();
652 
653 	/* Replace the global interrupt handler */
654 	real_handler = global_clock_event->event_handler;
655 	global_clock_event->event_handler = lapic_cal_handler;
656 
657 	/*
658 	 * Setup the APIC counter to maximum. There is no way the lapic
659 	 * can underflow in the 100ms detection time frame
660 	 */
661 	__setup_APIC_LVTT(0xffffffff, 0, 0);
662 
663 	/* Let the interrupts run */
664 	local_irq_enable();
665 
666 	while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
667 		cpu_relax();
668 
669 	local_irq_disable();
670 
671 	/* Restore the real event handler */
672 	global_clock_event->event_handler = real_handler;
673 
674 	/* Build delta t1-t2 as apic timer counts down */
675 	delta = lapic_cal_t1 - lapic_cal_t2;
676 	apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
677 
678 	deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
679 
680 	/* we trust the PM based calibration if possible */
681 	pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
682 					&delta, &deltatsc);
683 
684 	/* Calculate the scaled math multiplication factor */
685 	lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
686 				       lapic_clockevent.shift);
687 	lapic_clockevent.max_delta_ns =
688 		clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
689 	lapic_clockevent.min_delta_ns =
690 		clockevent_delta2ns(0xF, &lapic_clockevent);
691 
692 	calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
693 
694 	apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
695 	apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
696 	apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
697 		    calibration_result);
698 
699 	if (cpu_has_tsc) {
700 		apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
701 			    "%ld.%04ld MHz.\n",
702 			    (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
703 			    (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
704 	}
705 
706 	apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
707 		    "%u.%04u MHz.\n",
708 		    calibration_result / (1000000 / HZ),
709 		    calibration_result % (1000000 / HZ));
710 
711 	/*
712 	 * Do a sanity check on the APIC calibration result
713 	 */
714 	if (calibration_result < (1000000 / HZ)) {
715 		local_irq_enable();
716 		pr_warning("APIC frequency too slow, disabling apic timer\n");
717 		return -1;
718 	}
719 
720 	levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
721 
722 	/*
723 	 * PM timer calibration failed or not turned on
724 	 * so lets try APIC timer based calibration
725 	 */
726 	if (!pm_referenced) {
727 		apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
728 
729 		/*
730 		 * Setup the apic timer manually
731 		 */
732 		levt->event_handler = lapic_cal_handler;
733 		lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
734 		lapic_cal_loops = -1;
735 
736 		/* Let the interrupts run */
737 		local_irq_enable();
738 
739 		while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
740 			cpu_relax();
741 
742 		/* Stop the lapic timer */
743 		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
744 
745 		/* Jiffies delta */
746 		deltaj = lapic_cal_j2 - lapic_cal_j1;
747 		apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
748 
749 		/* Check, if the jiffies result is consistent */
750 		if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
751 			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
752 		else
753 			levt->features |= CLOCK_EVT_FEAT_DUMMY;
754 	} else
755 		local_irq_enable();
756 
757 	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
758 		pr_warning("APIC timer disabled due to verification failure\n");
759 			return -1;
760 	}
761 
762 	return 0;
763 }
764 
765 /*
766  * Setup the boot APIC
767  *
768  * Calibrate and verify the result.
769  */
770 void __init setup_boot_APIC_clock(void)
771 {
772 	/*
773 	 * The local apic timer can be disabled via the kernel
774 	 * commandline or from the CPU detection code. Register the lapic
775 	 * timer as a dummy clock event source on SMP systems, so the
776 	 * broadcast mechanism is used. On UP systems simply ignore it.
777 	 */
778 	if (disable_apic_timer) {
779 		pr_info("Disabling APIC timer\n");
780 		/* No broadcast on UP ! */
781 		if (num_possible_cpus() > 1) {
782 			lapic_clockevent.mult = 1;
783 			setup_APIC_timer();
784 		}
785 		return;
786 	}
787 
788 	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
789 		    "calibrating APIC timer ...\n");
790 
791 	if (calibrate_APIC_clock()) {
792 		/* No broadcast on UP ! */
793 		if (num_possible_cpus() > 1)
794 			setup_APIC_timer();
795 		return;
796 	}
797 
798 	/*
799 	 * If nmi_watchdog is set to IO_APIC, we need the
800 	 * PIT/HPET going.  Otherwise register lapic as a dummy
801 	 * device.
802 	 */
803 	if (nmi_watchdog != NMI_IO_APIC)
804 		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
805 	else
806 		pr_warning("APIC timer registered as dummy,"
807 			" due to nmi_watchdog=%d!\n", nmi_watchdog);
808 
809 	/* Setup the lapic or request the broadcast */
810 	setup_APIC_timer();
811 }
812 
813 void __cpuinit setup_secondary_APIC_clock(void)
814 {
815 	setup_APIC_timer();
816 }
817 
818 /*
819  * The guts of the apic timer interrupt
820  */
821 static void local_apic_timer_interrupt(void)
822 {
823 	int cpu = smp_processor_id();
824 	struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
825 
826 	/*
827 	 * Normally we should not be here till LAPIC has been initialized but
828 	 * in some cases like kdump, its possible that there is a pending LAPIC
829 	 * timer interrupt from previous kernel's context and is delivered in
830 	 * new kernel the moment interrupts are enabled.
831 	 *
832 	 * Interrupts are enabled early and LAPIC is setup much later, hence
833 	 * its possible that when we get here evt->event_handler is NULL.
834 	 * Check for event_handler being NULL and discard the interrupt as
835 	 * spurious.
836 	 */
837 	if (!evt->event_handler) {
838 		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
839 		/* Switch it off */
840 		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
841 		return;
842 	}
843 
844 	/*
845 	 * the NMI deadlock-detector uses this.
846 	 */
847 	inc_irq_stat(apic_timer_irqs);
848 
849 	evt->event_handler(evt);
850 }
851 
852 /*
853  * Local APIC timer interrupt. This is the most natural way for doing
854  * local interrupts, but local timer interrupts can be emulated by
855  * broadcast interrupts too. [in case the hw doesn't support APIC timers]
856  *
857  * [ if a single-CPU system runs an SMP kernel then we call the local
858  *   interrupt as well. Thus we cannot inline the local irq ... ]
859  */
860 void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
861 {
862 	struct pt_regs *old_regs = set_irq_regs(regs);
863 
864 	/*
865 	 * NOTE! We'd better ACK the irq immediately,
866 	 * because timer handling can be slow.
867 	 */
868 	ack_APIC_irq();
869 	/*
870 	 * update_process_times() expects us to have done irq_enter().
871 	 * Besides, if we don't timer interrupts ignore the global
872 	 * interrupt lock, which is the WrongThing (tm) to do.
873 	 */
874 	exit_idle();
875 	irq_enter();
876 	local_apic_timer_interrupt();
877 	irq_exit();
878 
879 	set_irq_regs(old_regs);
880 }
881 
882 int setup_profiling_timer(unsigned int multiplier)
883 {
884 	return -EINVAL;
885 }
886 
887 /*
888  * Local APIC start and shutdown
889  */
890 
891 /**
892  * clear_local_APIC - shutdown the local APIC
893  *
894  * This is called, when a CPU is disabled and before rebooting, so the state of
895  * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
896  * leftovers during boot.
897  */
898 void clear_local_APIC(void)
899 {
900 	int maxlvt;
901 	u32 v;
902 
903 	/* APIC hasn't been mapped yet */
904 	if (!x2apic_mode && !apic_phys)
905 		return;
906 
907 	maxlvt = lapic_get_maxlvt();
908 	/*
909 	 * Masking an LVT entry can trigger a local APIC error
910 	 * if the vector is zero. Mask LVTERR first to prevent this.
911 	 */
912 	if (maxlvt >= 3) {
913 		v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
914 		apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
915 	}
916 	/*
917 	 * Careful: we have to set masks only first to deassert
918 	 * any level-triggered sources.
919 	 */
920 	v = apic_read(APIC_LVTT);
921 	apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
922 	v = apic_read(APIC_LVT0);
923 	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
924 	v = apic_read(APIC_LVT1);
925 	apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
926 	if (maxlvt >= 4) {
927 		v = apic_read(APIC_LVTPC);
928 		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
929 	}
930 
931 	/* lets not touch this if we didn't frob it */
932 #ifdef CONFIG_X86_THERMAL_VECTOR
933 	if (maxlvt >= 5) {
934 		v = apic_read(APIC_LVTTHMR);
935 		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
936 	}
937 #endif
938 #ifdef CONFIG_X86_MCE_INTEL
939 	if (maxlvt >= 6) {
940 		v = apic_read(APIC_LVTCMCI);
941 		if (!(v & APIC_LVT_MASKED))
942 			apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
943 	}
944 #endif
945 
946 	/*
947 	 * Clean APIC state for other OSs:
948 	 */
949 	apic_write(APIC_LVTT, APIC_LVT_MASKED);
950 	apic_write(APIC_LVT0, APIC_LVT_MASKED);
951 	apic_write(APIC_LVT1, APIC_LVT_MASKED);
952 	if (maxlvt >= 3)
953 		apic_write(APIC_LVTERR, APIC_LVT_MASKED);
954 	if (maxlvt >= 4)
955 		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
956 
957 	/* Integrated APIC (!82489DX) ? */
958 	if (lapic_is_integrated()) {
959 		if (maxlvt > 3)
960 			/* Clear ESR due to Pentium errata 3AP and 11AP */
961 			apic_write(APIC_ESR, 0);
962 		apic_read(APIC_ESR);
963 	}
964 }
965 
966 /**
967  * disable_local_APIC - clear and disable the local APIC
968  */
969 void disable_local_APIC(void)
970 {
971 	unsigned int value;
972 
973 	/* APIC hasn't been mapped yet */
974 	if (!x2apic_mode && !apic_phys)
975 		return;
976 
977 	clear_local_APIC();
978 
979 	/*
980 	 * Disable APIC (implies clearing of registers
981 	 * for 82489DX!).
982 	 */
983 	value = apic_read(APIC_SPIV);
984 	value &= ~APIC_SPIV_APIC_ENABLED;
985 	apic_write(APIC_SPIV, value);
986 
987 #ifdef CONFIG_X86_32
988 	/*
989 	 * When LAPIC was disabled by the BIOS and enabled by the kernel,
990 	 * restore the disabled state.
991 	 */
992 	if (enabled_via_apicbase) {
993 		unsigned int l, h;
994 
995 		rdmsr(MSR_IA32_APICBASE, l, h);
996 		l &= ~MSR_IA32_APICBASE_ENABLE;
997 		wrmsr(MSR_IA32_APICBASE, l, h);
998 	}
999 #endif
1000 }
1001 
1002 /*
1003  * If Linux enabled the LAPIC against the BIOS default disable it down before
1004  * re-entering the BIOS on shutdown.  Otherwise the BIOS may get confused and
1005  * not power-off.  Additionally clear all LVT entries before disable_local_APIC
1006  * for the case where Linux didn't enable the LAPIC.
1007  */
1008 void lapic_shutdown(void)
1009 {
1010 	unsigned long flags;
1011 
1012 	if (!cpu_has_apic && !apic_from_smp_config())
1013 		return;
1014 
1015 	local_irq_save(flags);
1016 
1017 #ifdef CONFIG_X86_32
1018 	if (!enabled_via_apicbase)
1019 		clear_local_APIC();
1020 	else
1021 #endif
1022 		disable_local_APIC();
1023 
1024 
1025 	local_irq_restore(flags);
1026 }
1027 
1028 /*
1029  * This is to verify that we're looking at a real local APIC.
1030  * Check these against your board if the CPUs aren't getting
1031  * started for no apparent reason.
1032  */
1033 int __init verify_local_APIC(void)
1034 {
1035 	unsigned int reg0, reg1;
1036 
1037 	/*
1038 	 * The version register is read-only in a real APIC.
1039 	 */
1040 	reg0 = apic_read(APIC_LVR);
1041 	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
1042 	apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
1043 	reg1 = apic_read(APIC_LVR);
1044 	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
1045 
1046 	/*
1047 	 * The two version reads above should print the same
1048 	 * numbers.  If the second one is different, then we
1049 	 * poke at a non-APIC.
1050 	 */
1051 	if (reg1 != reg0)
1052 		return 0;
1053 
1054 	/*
1055 	 * Check if the version looks reasonably.
1056 	 */
1057 	reg1 = GET_APIC_VERSION(reg0);
1058 	if (reg1 == 0x00 || reg1 == 0xff)
1059 		return 0;
1060 	reg1 = lapic_get_maxlvt();
1061 	if (reg1 < 0x02 || reg1 == 0xff)
1062 		return 0;
1063 
1064 	/*
1065 	 * The ID register is read/write in a real APIC.
1066 	 */
1067 	reg0 = apic_read(APIC_ID);
1068 	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
1069 	apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
1070 	reg1 = apic_read(APIC_ID);
1071 	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
1072 	apic_write(APIC_ID, reg0);
1073 	if (reg1 != (reg0 ^ apic->apic_id_mask))
1074 		return 0;
1075 
1076 	/*
1077 	 * The next two are just to see if we have sane values.
1078 	 * They're only really relevant if we're in Virtual Wire
1079 	 * compatibility mode, but most boxes are anymore.
1080 	 */
1081 	reg0 = apic_read(APIC_LVT0);
1082 	apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
1083 	reg1 = apic_read(APIC_LVT1);
1084 	apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
1085 
1086 	return 1;
1087 }
1088 
1089 /**
1090  * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1091  */
1092 void __init sync_Arb_IDs(void)
1093 {
1094 	/*
1095 	 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1096 	 * needed on AMD.
1097 	 */
1098 	if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1099 		return;
1100 
1101 	/*
1102 	 * Wait for idle.
1103 	 */
1104 	apic_wait_icr_idle();
1105 
1106 	apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1107 	apic_write(APIC_ICR, APIC_DEST_ALLINC |
1108 			APIC_INT_LEVELTRIG | APIC_DM_INIT);
1109 }
1110 
1111 /*
1112  * An initial setup of the virtual wire mode.
1113  */
1114 void __init init_bsp_APIC(void)
1115 {
1116 	unsigned int value;
1117 
1118 	/*
1119 	 * Don't do the setup now if we have a SMP BIOS as the
1120 	 * through-I/O-APIC virtual wire mode might be active.
1121 	 */
1122 	if (smp_found_config || !cpu_has_apic)
1123 		return;
1124 
1125 	/*
1126 	 * Do not trust the local APIC being empty at bootup.
1127 	 */
1128 	clear_local_APIC();
1129 
1130 	/*
1131 	 * Enable APIC.
1132 	 */
1133 	value = apic_read(APIC_SPIV);
1134 	value &= ~APIC_VECTOR_MASK;
1135 	value |= APIC_SPIV_APIC_ENABLED;
1136 
1137 #ifdef CONFIG_X86_32
1138 	/* This bit is reserved on P4/Xeon and should be cleared */
1139 	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1140 	    (boot_cpu_data.x86 == 15))
1141 		value &= ~APIC_SPIV_FOCUS_DISABLED;
1142 	else
1143 #endif
1144 		value |= APIC_SPIV_FOCUS_DISABLED;
1145 	value |= SPURIOUS_APIC_VECTOR;
1146 	apic_write(APIC_SPIV, value);
1147 
1148 	/*
1149 	 * Set up the virtual wire mode.
1150 	 */
1151 	apic_write(APIC_LVT0, APIC_DM_EXTINT);
1152 	value = APIC_DM_NMI;
1153 	if (!lapic_is_integrated())		/* 82489DX */
1154 		value |= APIC_LVT_LEVEL_TRIGGER;
1155 	apic_write(APIC_LVT1, value);
1156 }
1157 
1158 static void __cpuinit lapic_setup_esr(void)
1159 {
1160 	unsigned int oldvalue, value, maxlvt;
1161 
1162 	if (!lapic_is_integrated()) {
1163 		pr_info("No ESR for 82489DX.\n");
1164 		return;
1165 	}
1166 
1167 	if (apic->disable_esr) {
1168 		/*
1169 		 * Something untraceable is creating bad interrupts on
1170 		 * secondary quads ... for the moment, just leave the
1171 		 * ESR disabled - we can't do anything useful with the
1172 		 * errors anyway - mbligh
1173 		 */
1174 		pr_info("Leaving ESR disabled.\n");
1175 		return;
1176 	}
1177 
1178 	maxlvt = lapic_get_maxlvt();
1179 	if (maxlvt > 3)		/* Due to the Pentium erratum 3AP. */
1180 		apic_write(APIC_ESR, 0);
1181 	oldvalue = apic_read(APIC_ESR);
1182 
1183 	/* enables sending errors */
1184 	value = ERROR_APIC_VECTOR;
1185 	apic_write(APIC_LVTERR, value);
1186 
1187 	/*
1188 	 * spec says clear errors after enabling vector.
1189 	 */
1190 	if (maxlvt > 3)
1191 		apic_write(APIC_ESR, 0);
1192 	value = apic_read(APIC_ESR);
1193 	if (value != oldvalue)
1194 		apic_printk(APIC_VERBOSE, "ESR value before enabling "
1195 			"vector: 0x%08x  after: 0x%08x\n",
1196 			oldvalue, value);
1197 }
1198 
1199 
1200 /**
1201  * setup_local_APIC - setup the local APIC
1202  */
1203 void __cpuinit setup_local_APIC(void)
1204 {
1205 	unsigned int value, queued;
1206 	int i, j, acked = 0;
1207 	unsigned long long tsc = 0, ntsc;
1208 	long long max_loops = cpu_khz;
1209 
1210 	if (cpu_has_tsc)
1211 		rdtscll(tsc);
1212 
1213 	if (disable_apic) {
1214 		arch_disable_smp_support();
1215 		return;
1216 	}
1217 
1218 #ifdef CONFIG_X86_32
1219 	/* Pound the ESR really hard over the head with a big hammer - mbligh */
1220 	if (lapic_is_integrated() && apic->disable_esr) {
1221 		apic_write(APIC_ESR, 0);
1222 		apic_write(APIC_ESR, 0);
1223 		apic_write(APIC_ESR, 0);
1224 		apic_write(APIC_ESR, 0);
1225 	}
1226 #endif
1227 	perf_events_lapic_init();
1228 
1229 	preempt_disable();
1230 
1231 	/*
1232 	 * Double-check whether this APIC is really registered.
1233 	 * This is meaningless in clustered apic mode, so we skip it.
1234 	 */
1235 	BUG_ON(!apic->apic_id_registered());
1236 
1237 	/*
1238 	 * Intel recommends to set DFR, LDR and TPR before enabling
1239 	 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
1240 	 * document number 292116).  So here it goes...
1241 	 */
1242 	apic->init_apic_ldr();
1243 
1244 	/*
1245 	 * Set Task Priority to 'accept all'. We never change this
1246 	 * later on.
1247 	 */
1248 	value = apic_read(APIC_TASKPRI);
1249 	value &= ~APIC_TPRI_MASK;
1250 	apic_write(APIC_TASKPRI, value);
1251 
1252 	/*
1253 	 * After a crash, we no longer service the interrupts and a pending
1254 	 * interrupt from previous kernel might still have ISR bit set.
1255 	 *
1256 	 * Most probably by now CPU has serviced that pending interrupt and
1257 	 * it might not have done the ack_APIC_irq() because it thought,
1258 	 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1259 	 * does not clear the ISR bit and cpu thinks it has already serivced
1260 	 * the interrupt. Hence a vector might get locked. It was noticed
1261 	 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1262 	 */
1263 	do {
1264 		queued = 0;
1265 		for (i = APIC_ISR_NR - 1; i >= 0; i--)
1266 			queued |= apic_read(APIC_IRR + i*0x10);
1267 
1268 		for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1269 			value = apic_read(APIC_ISR + i*0x10);
1270 			for (j = 31; j >= 0; j--) {
1271 				if (value & (1<<j)) {
1272 					ack_APIC_irq();
1273 					acked++;
1274 				}
1275 			}
1276 		}
1277 		if (acked > 256) {
1278 			printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n",
1279 			       acked);
1280 			break;
1281 		}
1282 		if (cpu_has_tsc) {
1283 			rdtscll(ntsc);
1284 			max_loops = (cpu_khz << 10) - (ntsc - tsc);
1285 		} else
1286 			max_loops--;
1287 	} while (queued && max_loops > 0);
1288 	WARN_ON(max_loops <= 0);
1289 
1290 	/*
1291 	 * Now that we are all set up, enable the APIC
1292 	 */
1293 	value = apic_read(APIC_SPIV);
1294 	value &= ~APIC_VECTOR_MASK;
1295 	/*
1296 	 * Enable APIC
1297 	 */
1298 	value |= APIC_SPIV_APIC_ENABLED;
1299 
1300 #ifdef CONFIG_X86_32
1301 	/*
1302 	 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1303 	 * certain networking cards. If high frequency interrupts are
1304 	 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1305 	 * entry is masked/unmasked at a high rate as well then sooner or
1306 	 * later IOAPIC line gets 'stuck', no more interrupts are received
1307 	 * from the device. If focus CPU is disabled then the hang goes
1308 	 * away, oh well :-(
1309 	 *
1310 	 * [ This bug can be reproduced easily with a level-triggered
1311 	 *   PCI Ne2000 networking cards and PII/PIII processors, dual
1312 	 *   BX chipset. ]
1313 	 */
1314 	/*
1315 	 * Actually disabling the focus CPU check just makes the hang less
1316 	 * frequent as it makes the interrupt distributon model be more
1317 	 * like LRU than MRU (the short-term load is more even across CPUs).
1318 	 * See also the comment in end_level_ioapic_irq().  --macro
1319 	 */
1320 
1321 	/*
1322 	 * - enable focus processor (bit==0)
1323 	 * - 64bit mode always use processor focus
1324 	 *   so no need to set it
1325 	 */
1326 	value &= ~APIC_SPIV_FOCUS_DISABLED;
1327 #endif
1328 
1329 	/*
1330 	 * Set spurious IRQ vector
1331 	 */
1332 	value |= SPURIOUS_APIC_VECTOR;
1333 	apic_write(APIC_SPIV, value);
1334 
1335 	/*
1336 	 * Set up LVT0, LVT1:
1337 	 *
1338 	 * set up through-local-APIC on the BP's LINT0. This is not
1339 	 * strictly necessary in pure symmetric-IO mode, but sometimes
1340 	 * we delegate interrupts to the 8259A.
1341 	 */
1342 	/*
1343 	 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1344 	 */
1345 	value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1346 	if (!smp_processor_id() && (pic_mode || !value)) {
1347 		value = APIC_DM_EXTINT;
1348 		apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1349 				smp_processor_id());
1350 	} else {
1351 		value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1352 		apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1353 				smp_processor_id());
1354 	}
1355 	apic_write(APIC_LVT0, value);
1356 
1357 	/*
1358 	 * only the BP should see the LINT1 NMI signal, obviously.
1359 	 */
1360 	if (!smp_processor_id())
1361 		value = APIC_DM_NMI;
1362 	else
1363 		value = APIC_DM_NMI | APIC_LVT_MASKED;
1364 	if (!lapic_is_integrated())		/* 82489DX */
1365 		value |= APIC_LVT_LEVEL_TRIGGER;
1366 	apic_write(APIC_LVT1, value);
1367 
1368 	preempt_enable();
1369 
1370 #ifdef CONFIG_X86_MCE_INTEL
1371 	/* Recheck CMCI information after local APIC is up on CPU #0 */
1372 	if (smp_processor_id() == 0)
1373 		cmci_recheck();
1374 #endif
1375 }
1376 
1377 void __cpuinit end_local_APIC_setup(void)
1378 {
1379 	lapic_setup_esr();
1380 
1381 #ifdef CONFIG_X86_32
1382 	{
1383 		unsigned int value;
1384 		/* Disable the local apic timer */
1385 		value = apic_read(APIC_LVTT);
1386 		value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1387 		apic_write(APIC_LVTT, value);
1388 	}
1389 #endif
1390 
1391 	setup_apic_nmi_watchdog(NULL);
1392 	apic_pm_activate();
1393 }
1394 
1395 #ifdef CONFIG_X86_X2APIC
1396 void check_x2apic(void)
1397 {
1398 	if (x2apic_enabled()) {
1399 		pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
1400 		x2apic_preenabled = x2apic_mode = 1;
1401 	}
1402 }
1403 
1404 void enable_x2apic(void)
1405 {
1406 	int msr, msr2;
1407 
1408 	if (!x2apic_mode)
1409 		return;
1410 
1411 	rdmsr(MSR_IA32_APICBASE, msr, msr2);
1412 	if (!(msr & X2APIC_ENABLE)) {
1413 		printk_once(KERN_INFO "Enabling x2apic\n");
1414 		wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1415 	}
1416 }
1417 #endif /* CONFIG_X86_X2APIC */
1418 
1419 int __init enable_IR(void)
1420 {
1421 #ifdef CONFIG_INTR_REMAP
1422 	if (!intr_remapping_supported()) {
1423 		pr_debug("intr-remapping not supported\n");
1424 		return 0;
1425 	}
1426 
1427 	if (!x2apic_preenabled && skip_ioapic_setup) {
1428 		pr_info("Skipped enabling intr-remap because of skipping "
1429 			"io-apic setup\n");
1430 		return 0;
1431 	}
1432 
1433 	if (enable_intr_remapping(x2apic_supported()))
1434 		return 0;
1435 
1436 	pr_info("Enabled Interrupt-remapping\n");
1437 
1438 	return 1;
1439 
1440 #endif
1441 	return 0;
1442 }
1443 
1444 void __init enable_IR_x2apic(void)
1445 {
1446 	unsigned long flags;
1447 	struct IO_APIC_route_entry **ioapic_entries = NULL;
1448 	int ret, x2apic_enabled = 0;
1449 	int dmar_table_init_ret;
1450 
1451 	dmar_table_init_ret = dmar_table_init();
1452 	if (dmar_table_init_ret && !x2apic_supported())
1453 		return;
1454 
1455 	ioapic_entries = alloc_ioapic_entries();
1456 	if (!ioapic_entries) {
1457 		pr_err("Allocate ioapic_entries failed\n");
1458 		goto out;
1459 	}
1460 
1461 	ret = save_IO_APIC_setup(ioapic_entries);
1462 	if (ret) {
1463 		pr_info("Saving IO-APIC state failed: %d\n", ret);
1464 		goto out;
1465 	}
1466 
1467 	local_irq_save(flags);
1468 	legacy_pic->mask_all();
1469 	mask_IO_APIC_setup(ioapic_entries);
1470 
1471 	if (dmar_table_init_ret)
1472 		ret = 0;
1473 	else
1474 		ret = enable_IR();
1475 
1476 	if (!ret) {
1477 		/* IR is required if there is APIC ID > 255 even when running
1478 		 * under KVM
1479 		 */
1480 		if (max_physical_apicid > 255 || !kvm_para_available())
1481 			goto nox2apic;
1482 		/*
1483 		 * without IR all CPUs can be addressed by IOAPIC/MSI
1484 		 * only in physical mode
1485 		 */
1486 		x2apic_force_phys();
1487 	}
1488 
1489 	x2apic_enabled = 1;
1490 
1491 	if (x2apic_supported() && !x2apic_mode) {
1492 		x2apic_mode = 1;
1493 		enable_x2apic();
1494 		pr_info("Enabled x2apic\n");
1495 	}
1496 
1497 nox2apic:
1498 	if (!ret) /* IR enabling failed */
1499 		restore_IO_APIC_setup(ioapic_entries);
1500 	legacy_pic->restore_mask();
1501 	local_irq_restore(flags);
1502 
1503 out:
1504 	if (ioapic_entries)
1505 		free_ioapic_entries(ioapic_entries);
1506 
1507 	if (x2apic_enabled)
1508 		return;
1509 
1510 	if (x2apic_preenabled)
1511 		panic("x2apic: enabled by BIOS but kernel init failed.");
1512 	else if (cpu_has_x2apic)
1513 		pr_info("Not enabling x2apic, Intr-remapping init failed.\n");
1514 }
1515 
1516 #ifdef CONFIG_X86_64
1517 /*
1518  * Detect and enable local APICs on non-SMP boards.
1519  * Original code written by Keir Fraser.
1520  * On AMD64 we trust the BIOS - if it says no APIC it is likely
1521  * not correctly set up (usually the APIC timer won't work etc.)
1522  */
1523 static int __init detect_init_APIC(void)
1524 {
1525 	if (!cpu_has_apic) {
1526 		pr_info("No local APIC present\n");
1527 		return -1;
1528 	}
1529 
1530 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1531 	return 0;
1532 }
1533 #else
1534 /*
1535  * Detect and initialize APIC
1536  */
1537 static int __init detect_init_APIC(void)
1538 {
1539 	u32 h, l, features;
1540 
1541 	/* Disabled by kernel option? */
1542 	if (disable_apic)
1543 		return -1;
1544 
1545 	switch (boot_cpu_data.x86_vendor) {
1546 	case X86_VENDOR_AMD:
1547 		if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1548 		    (boot_cpu_data.x86 >= 15))
1549 			break;
1550 		goto no_apic;
1551 	case X86_VENDOR_INTEL:
1552 		if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1553 		    (boot_cpu_data.x86 == 5 && cpu_has_apic))
1554 			break;
1555 		goto no_apic;
1556 	default:
1557 		goto no_apic;
1558 	}
1559 
1560 	if (!cpu_has_apic) {
1561 		/*
1562 		 * Over-ride BIOS and try to enable the local APIC only if
1563 		 * "lapic" specified.
1564 		 */
1565 		if (!force_enable_local_apic) {
1566 			pr_info("Local APIC disabled by BIOS -- "
1567 				"you can enable it with \"lapic\"\n");
1568 			return -1;
1569 		}
1570 		/*
1571 		 * Some BIOSes disable the local APIC in the APIC_BASE
1572 		 * MSR. This can only be done in software for Intel P6 or later
1573 		 * and AMD K7 (Model > 1) or later.
1574 		 */
1575 		rdmsr(MSR_IA32_APICBASE, l, h);
1576 		if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1577 			pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1578 			l &= ~MSR_IA32_APICBASE_BASE;
1579 			l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
1580 			wrmsr(MSR_IA32_APICBASE, l, h);
1581 			enabled_via_apicbase = 1;
1582 		}
1583 	}
1584 	/*
1585 	 * The APIC feature bit should now be enabled
1586 	 * in `cpuid'
1587 	 */
1588 	features = cpuid_edx(1);
1589 	if (!(features & (1 << X86_FEATURE_APIC))) {
1590 		pr_warning("Could not enable APIC!\n");
1591 		return -1;
1592 	}
1593 	set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1594 	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1595 
1596 	/* The BIOS may have set up the APIC at some other address */
1597 	rdmsr(MSR_IA32_APICBASE, l, h);
1598 	if (l & MSR_IA32_APICBASE_ENABLE)
1599 		mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1600 
1601 	pr_info("Found and enabled local APIC!\n");
1602 
1603 	apic_pm_activate();
1604 
1605 	return 0;
1606 
1607 no_apic:
1608 	pr_info("No local APIC present or hardware disabled\n");
1609 	return -1;
1610 }
1611 #endif
1612 
1613 #ifdef CONFIG_X86_64
1614 void __init early_init_lapic_mapping(void)
1615 {
1616 	/*
1617 	 * If no local APIC can be found then go out
1618 	 * : it means there is no mpatable and MADT
1619 	 */
1620 	if (!smp_found_config)
1621 		return;
1622 
1623 	set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);
1624 	apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1625 		    APIC_BASE, mp_lapic_addr);
1626 
1627 	/*
1628 	 * Fetch the APIC ID of the BSP in case we have a
1629 	 * default configuration (or the MP table is broken).
1630 	 */
1631 	boot_cpu_physical_apicid = read_apic_id();
1632 }
1633 #endif
1634 
1635 /**
1636  * init_apic_mappings - initialize APIC mappings
1637  */
1638 void __init init_apic_mappings(void)
1639 {
1640 	unsigned int new_apicid;
1641 
1642 	if (x2apic_mode) {
1643 		boot_cpu_physical_apicid = read_apic_id();
1644 		return;
1645 	}
1646 
1647 	/* If no local APIC can be found return early */
1648 	if (!smp_found_config && detect_init_APIC()) {
1649 		/* lets NOP'ify apic operations */
1650 		pr_info("APIC: disable apic facility\n");
1651 		apic_disable();
1652 	} else {
1653 		apic_phys = mp_lapic_addr;
1654 
1655 		/*
1656 		 * acpi lapic path already maps that address in
1657 		 * acpi_register_lapic_address()
1658 		 */
1659 		if (!acpi_lapic && !smp_found_config)
1660 			set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1661 
1662 		apic_printk(APIC_VERBOSE, "mapped APIC to %08lx (%08lx)\n",
1663 					APIC_BASE, apic_phys);
1664 	}
1665 
1666 	/*
1667 	 * Fetch the APIC ID of the BSP in case we have a
1668 	 * default configuration (or the MP table is broken).
1669 	 */
1670 	new_apicid = read_apic_id();
1671 	if (boot_cpu_physical_apicid != new_apicid) {
1672 		boot_cpu_physical_apicid = new_apicid;
1673 		/*
1674 		 * yeah -- we lie about apic_version
1675 		 * in case if apic was disabled via boot option
1676 		 * but it's not a problem for SMP compiled kernel
1677 		 * since smp_sanity_check is prepared for such a case
1678 		 * and disable smp mode
1679 		 */
1680 		apic_version[new_apicid] =
1681 			 GET_APIC_VERSION(apic_read(APIC_LVR));
1682 	}
1683 }
1684 
1685 /*
1686  * This initializes the IO-APIC and APIC hardware if this is
1687  * a UP kernel.
1688  */
1689 int apic_version[MAX_APICS];
1690 
1691 int __init APIC_init_uniprocessor(void)
1692 {
1693 	if (disable_apic) {
1694 		pr_info("Apic disabled\n");
1695 		return -1;
1696 	}
1697 #ifdef CONFIG_X86_64
1698 	if (!cpu_has_apic) {
1699 		disable_apic = 1;
1700 		pr_info("Apic disabled by BIOS\n");
1701 		return -1;
1702 	}
1703 #else
1704 	if (!smp_found_config && !cpu_has_apic)
1705 		return -1;
1706 
1707 	/*
1708 	 * Complain if the BIOS pretends there is one.
1709 	 */
1710 	if (!cpu_has_apic &&
1711 	    APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1712 		pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
1713 			boot_cpu_physical_apicid);
1714 		return -1;
1715 	}
1716 #endif
1717 
1718 	default_setup_apic_routing();
1719 
1720 	verify_local_APIC();
1721 	connect_bsp_APIC();
1722 
1723 #ifdef CONFIG_X86_64
1724 	apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1725 #else
1726 	/*
1727 	 * Hack: In case of kdump, after a crash, kernel might be booting
1728 	 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1729 	 * might be zero if read from MP tables. Get it from LAPIC.
1730 	 */
1731 # ifdef CONFIG_CRASH_DUMP
1732 	boot_cpu_physical_apicid = read_apic_id();
1733 # endif
1734 #endif
1735 	physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1736 	setup_local_APIC();
1737 
1738 #ifdef CONFIG_X86_IO_APIC
1739 	/*
1740 	 * Now enable IO-APICs, actually call clear_IO_APIC
1741 	 * We need clear_IO_APIC before enabling error vector
1742 	 */
1743 	if (!skip_ioapic_setup && nr_ioapics)
1744 		enable_IO_APIC();
1745 #endif
1746 
1747 	end_local_APIC_setup();
1748 
1749 #ifdef CONFIG_X86_IO_APIC
1750 	if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1751 		setup_IO_APIC();
1752 	else {
1753 		nr_ioapics = 0;
1754 		localise_nmi_watchdog();
1755 	}
1756 #else
1757 	localise_nmi_watchdog();
1758 #endif
1759 
1760 	x86_init.timers.setup_percpu_clockev();
1761 #ifdef CONFIG_X86_64
1762 	check_nmi_watchdog();
1763 #endif
1764 
1765 	return 0;
1766 }
1767 
1768 /*
1769  * Local APIC interrupts
1770  */
1771 
1772 /*
1773  * This interrupt should _never_ happen with our APIC/SMP architecture
1774  */
1775 void smp_spurious_interrupt(struct pt_regs *regs)
1776 {
1777 	u32 v;
1778 
1779 	exit_idle();
1780 	irq_enter();
1781 	/*
1782 	 * Check if this really is a spurious interrupt and ACK it
1783 	 * if it is a vectored one.  Just in case...
1784 	 * Spurious interrupts should not be ACKed.
1785 	 */
1786 	v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1787 	if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1788 		ack_APIC_irq();
1789 
1790 	inc_irq_stat(irq_spurious_count);
1791 
1792 	/* see sw-dev-man vol 3, chapter 7.4.13.5 */
1793 	pr_info("spurious APIC interrupt on CPU#%d, "
1794 		"should never happen.\n", smp_processor_id());
1795 	irq_exit();
1796 }
1797 
1798 /*
1799  * This interrupt should never happen with our APIC/SMP architecture
1800  */
1801 void smp_error_interrupt(struct pt_regs *regs)
1802 {
1803 	u32 v, v1;
1804 
1805 	exit_idle();
1806 	irq_enter();
1807 	/* First tickle the hardware, only then report what went on. -- REW */
1808 	v = apic_read(APIC_ESR);
1809 	apic_write(APIC_ESR, 0);
1810 	v1 = apic_read(APIC_ESR);
1811 	ack_APIC_irq();
1812 	atomic_inc(&irq_err_count);
1813 
1814 	/*
1815 	 * Here is what the APIC error bits mean:
1816 	 * 0: Send CS error
1817 	 * 1: Receive CS error
1818 	 * 2: Send accept error
1819 	 * 3: Receive accept error
1820 	 * 4: Reserved
1821 	 * 5: Send illegal vector
1822 	 * 6: Received illegal vector
1823 	 * 7: Illegal register address
1824 	 */
1825 	pr_debug("APIC error on CPU%d: %02x(%02x)\n",
1826 		smp_processor_id(), v , v1);
1827 	irq_exit();
1828 }
1829 
1830 /**
1831  * connect_bsp_APIC - attach the APIC to the interrupt system
1832  */
1833 void __init connect_bsp_APIC(void)
1834 {
1835 #ifdef CONFIG_X86_32
1836 	if (pic_mode) {
1837 		/*
1838 		 * Do not trust the local APIC being empty at bootup.
1839 		 */
1840 		clear_local_APIC();
1841 		/*
1842 		 * PIC mode, enable APIC mode in the IMCR, i.e.  connect BSP's
1843 		 * local APIC to INT and NMI lines.
1844 		 */
1845 		apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1846 				"enabling APIC mode.\n");
1847 		imcr_pic_to_apic();
1848 	}
1849 #endif
1850 	if (apic->enable_apic_mode)
1851 		apic->enable_apic_mode();
1852 }
1853 
1854 /**
1855  * disconnect_bsp_APIC - detach the APIC from the interrupt system
1856  * @virt_wire_setup:	indicates, whether virtual wire mode is selected
1857  *
1858  * Virtual wire mode is necessary to deliver legacy interrupts even when the
1859  * APIC is disabled.
1860  */
1861 void disconnect_bsp_APIC(int virt_wire_setup)
1862 {
1863 	unsigned int value;
1864 
1865 #ifdef CONFIG_X86_32
1866 	if (pic_mode) {
1867 		/*
1868 		 * Put the board back into PIC mode (has an effect only on
1869 		 * certain older boards).  Note that APIC interrupts, including
1870 		 * IPIs, won't work beyond this point!  The only exception are
1871 		 * INIT IPIs.
1872 		 */
1873 		apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1874 				"entering PIC mode.\n");
1875 		imcr_apic_to_pic();
1876 		return;
1877 	}
1878 #endif
1879 
1880 	/* Go back to Virtual Wire compatibility mode */
1881 
1882 	/* For the spurious interrupt use vector F, and enable it */
1883 	value = apic_read(APIC_SPIV);
1884 	value &= ~APIC_VECTOR_MASK;
1885 	value |= APIC_SPIV_APIC_ENABLED;
1886 	value |= 0xf;
1887 	apic_write(APIC_SPIV, value);
1888 
1889 	if (!virt_wire_setup) {
1890 		/*
1891 		 * For LVT0 make it edge triggered, active high,
1892 		 * external and enabled
1893 		 */
1894 		value = apic_read(APIC_LVT0);
1895 		value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1896 			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1897 			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1898 		value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1899 		value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1900 		apic_write(APIC_LVT0, value);
1901 	} else {
1902 		/* Disable LVT0 */
1903 		apic_write(APIC_LVT0, APIC_LVT_MASKED);
1904 	}
1905 
1906 	/*
1907 	 * For LVT1 make it edge triggered, active high,
1908 	 * nmi and enabled
1909 	 */
1910 	value = apic_read(APIC_LVT1);
1911 	value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1912 			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1913 			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1914 	value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1915 	value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1916 	apic_write(APIC_LVT1, value);
1917 }
1918 
1919 void __cpuinit generic_processor_info(int apicid, int version)
1920 {
1921 	int cpu;
1922 
1923 	/*
1924 	 * Validate version
1925 	 */
1926 	if (version == 0x0) {
1927 		pr_warning("BIOS bug, APIC version is 0 for CPU#%d! "
1928 			   "fixing up to 0x10. (tell your hw vendor)\n",
1929 				version);
1930 		version = 0x10;
1931 	}
1932 	apic_version[apicid] = version;
1933 
1934 	if (num_processors >= nr_cpu_ids) {
1935 		int max = nr_cpu_ids;
1936 		int thiscpu = max + disabled_cpus;
1937 
1938 		pr_warning(
1939 			"ACPI: NR_CPUS/possible_cpus limit of %i reached."
1940 			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
1941 
1942 		disabled_cpus++;
1943 		return;
1944 	}
1945 
1946 	num_processors++;
1947 	cpu = cpumask_next_zero(-1, cpu_present_mask);
1948 
1949 	if (version != apic_version[boot_cpu_physical_apicid])
1950 		WARN_ONCE(1,
1951 			"ACPI: apic version mismatch, bootcpu: %x cpu %d: %x\n",
1952 			apic_version[boot_cpu_physical_apicid], cpu, version);
1953 
1954 	physid_set(apicid, phys_cpu_present_map);
1955 	if (apicid == boot_cpu_physical_apicid) {
1956 		/*
1957 		 * x86_bios_cpu_apicid is required to have processors listed
1958 		 * in same order as logical cpu numbers. Hence the first
1959 		 * entry is BSP, and so on.
1960 		 */
1961 		cpu = 0;
1962 	}
1963 	if (apicid > max_physical_apicid)
1964 		max_physical_apicid = apicid;
1965 
1966 #if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
1967 	early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1968 	early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1969 #endif
1970 
1971 	set_cpu_possible(cpu, true);
1972 	set_cpu_present(cpu, true);
1973 }
1974 
1975 int hard_smp_processor_id(void)
1976 {
1977 	return read_apic_id();
1978 }
1979 
1980 void default_init_apic_ldr(void)
1981 {
1982 	unsigned long val;
1983 
1984 	apic_write(APIC_DFR, APIC_DFR_VALUE);
1985 	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
1986 	val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
1987 	apic_write(APIC_LDR, val);
1988 }
1989 
1990 #ifdef CONFIG_X86_32
1991 int default_apicid_to_node(int logical_apicid)
1992 {
1993 #ifdef CONFIG_SMP
1994 	return apicid_2_node[hard_smp_processor_id()];
1995 #else
1996 	return 0;
1997 #endif
1998 }
1999 #endif
2000 
2001 /*
2002  * Power management
2003  */
2004 #ifdef CONFIG_PM
2005 
2006 static struct {
2007 	/*
2008 	 * 'active' is true if the local APIC was enabled by us and
2009 	 * not the BIOS; this signifies that we are also responsible
2010 	 * for disabling it before entering apm/acpi suspend
2011 	 */
2012 	int active;
2013 	/* r/w apic fields */
2014 	unsigned int apic_id;
2015 	unsigned int apic_taskpri;
2016 	unsigned int apic_ldr;
2017 	unsigned int apic_dfr;
2018 	unsigned int apic_spiv;
2019 	unsigned int apic_lvtt;
2020 	unsigned int apic_lvtpc;
2021 	unsigned int apic_lvt0;
2022 	unsigned int apic_lvt1;
2023 	unsigned int apic_lvterr;
2024 	unsigned int apic_tmict;
2025 	unsigned int apic_tdcr;
2026 	unsigned int apic_thmr;
2027 } apic_pm_state;
2028 
2029 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
2030 {
2031 	unsigned long flags;
2032 	int maxlvt;
2033 
2034 	if (!apic_pm_state.active)
2035 		return 0;
2036 
2037 	maxlvt = lapic_get_maxlvt();
2038 
2039 	apic_pm_state.apic_id = apic_read(APIC_ID);
2040 	apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2041 	apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2042 	apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2043 	apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2044 	apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2045 	if (maxlvt >= 4)
2046 		apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2047 	apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2048 	apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2049 	apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2050 	apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2051 	apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2052 #ifdef CONFIG_X86_THERMAL_VECTOR
2053 	if (maxlvt >= 5)
2054 		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2055 #endif
2056 
2057 	local_irq_save(flags);
2058 	disable_local_APIC();
2059 
2060 	if (intr_remapping_enabled)
2061 		disable_intr_remapping();
2062 
2063 	local_irq_restore(flags);
2064 	return 0;
2065 }
2066 
2067 static int lapic_resume(struct sys_device *dev)
2068 {
2069 	unsigned int l, h;
2070 	unsigned long flags;
2071 	int maxlvt;
2072 	int ret = 0;
2073 	struct IO_APIC_route_entry **ioapic_entries = NULL;
2074 
2075 	if (!apic_pm_state.active)
2076 		return 0;
2077 
2078 	local_irq_save(flags);
2079 	if (intr_remapping_enabled) {
2080 		ioapic_entries = alloc_ioapic_entries();
2081 		if (!ioapic_entries) {
2082 			WARN(1, "Alloc ioapic_entries in lapic resume failed.");
2083 			ret = -ENOMEM;
2084 			goto restore;
2085 		}
2086 
2087 		ret = save_IO_APIC_setup(ioapic_entries);
2088 		if (ret) {
2089 			WARN(1, "Saving IO-APIC state failed: %d\n", ret);
2090 			free_ioapic_entries(ioapic_entries);
2091 			goto restore;
2092 		}
2093 
2094 		mask_IO_APIC_setup(ioapic_entries);
2095 		legacy_pic->mask_all();
2096 	}
2097 
2098 	if (x2apic_mode)
2099 		enable_x2apic();
2100 	else {
2101 		/*
2102 		 * Make sure the APICBASE points to the right address
2103 		 *
2104 		 * FIXME! This will be wrong if we ever support suspend on
2105 		 * SMP! We'll need to do this as part of the CPU restore!
2106 		 */
2107 		rdmsr(MSR_IA32_APICBASE, l, h);
2108 		l &= ~MSR_IA32_APICBASE_BASE;
2109 		l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2110 		wrmsr(MSR_IA32_APICBASE, l, h);
2111 	}
2112 
2113 	maxlvt = lapic_get_maxlvt();
2114 	apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2115 	apic_write(APIC_ID, apic_pm_state.apic_id);
2116 	apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2117 	apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2118 	apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2119 	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2120 	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2121 	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2122 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2123 	if (maxlvt >= 5)
2124 		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2125 #endif
2126 	if (maxlvt >= 4)
2127 		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2128 	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2129 	apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2130 	apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2131 	apic_write(APIC_ESR, 0);
2132 	apic_read(APIC_ESR);
2133 	apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2134 	apic_write(APIC_ESR, 0);
2135 	apic_read(APIC_ESR);
2136 
2137 	if (intr_remapping_enabled) {
2138 		reenable_intr_remapping(x2apic_mode);
2139 		legacy_pic->restore_mask();
2140 		restore_IO_APIC_setup(ioapic_entries);
2141 		free_ioapic_entries(ioapic_entries);
2142 	}
2143 restore:
2144 	local_irq_restore(flags);
2145 
2146 	return ret;
2147 }
2148 
2149 /*
2150  * This device has no shutdown method - fully functioning local APICs
2151  * are needed on every CPU up until machine_halt/restart/poweroff.
2152  */
2153 
2154 static struct sysdev_class lapic_sysclass = {
2155 	.name		= "lapic",
2156 	.resume		= lapic_resume,
2157 	.suspend	= lapic_suspend,
2158 };
2159 
2160 static struct sys_device device_lapic = {
2161 	.id	= 0,
2162 	.cls	= &lapic_sysclass,
2163 };
2164 
2165 static void __cpuinit apic_pm_activate(void)
2166 {
2167 	apic_pm_state.active = 1;
2168 }
2169 
2170 static int __init init_lapic_sysfs(void)
2171 {
2172 	int error;
2173 
2174 	if (!cpu_has_apic)
2175 		return 0;
2176 	/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2177 
2178 	error = sysdev_class_register(&lapic_sysclass);
2179 	if (!error)
2180 		error = sysdev_register(&device_lapic);
2181 	return error;
2182 }
2183 
2184 /* local apic needs to resume before other devices access its registers. */
2185 core_initcall(init_lapic_sysfs);
2186 
2187 #else	/* CONFIG_PM */
2188 
2189 static void apic_pm_activate(void) { }
2190 
2191 #endif	/* CONFIG_PM */
2192 
2193 #ifdef CONFIG_X86_64
2194 
2195 static int __cpuinit apic_cluster_num(void)
2196 {
2197 	int i, clusters, zeros;
2198 	unsigned id;
2199 	u16 *bios_cpu_apicid;
2200 	DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2201 
2202 	bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2203 	bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2204 
2205 	for (i = 0; i < nr_cpu_ids; i++) {
2206 		/* are we being called early in kernel startup? */
2207 		if (bios_cpu_apicid) {
2208 			id = bios_cpu_apicid[i];
2209 		} else if (i < nr_cpu_ids) {
2210 			if (cpu_present(i))
2211 				id = per_cpu(x86_bios_cpu_apicid, i);
2212 			else
2213 				continue;
2214 		} else
2215 			break;
2216 
2217 		if (id != BAD_APICID)
2218 			__set_bit(APIC_CLUSTERID(id), clustermap);
2219 	}
2220 
2221 	/* Problem:  Partially populated chassis may not have CPUs in some of
2222 	 * the APIC clusters they have been allocated.  Only present CPUs have
2223 	 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2224 	 * Since clusters are allocated sequentially, count zeros only if
2225 	 * they are bounded by ones.
2226 	 */
2227 	clusters = 0;
2228 	zeros = 0;
2229 	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2230 		if (test_bit(i, clustermap)) {
2231 			clusters += 1 + zeros;
2232 			zeros = 0;
2233 		} else
2234 			++zeros;
2235 	}
2236 
2237 	return clusters;
2238 }
2239 
2240 static int __cpuinitdata multi_checked;
2241 static int __cpuinitdata multi;
2242 
2243 static int __cpuinit set_multi(const struct dmi_system_id *d)
2244 {
2245 	if (multi)
2246 		return 0;
2247 	pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2248 	multi = 1;
2249 	return 0;
2250 }
2251 
2252 static const __cpuinitconst struct dmi_system_id multi_dmi_table[] = {
2253 	{
2254 		.callback = set_multi,
2255 		.ident = "IBM System Summit2",
2256 		.matches = {
2257 			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2258 			DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2259 		},
2260 	},
2261 	{}
2262 };
2263 
2264 static void __cpuinit dmi_check_multi(void)
2265 {
2266 	if (multi_checked)
2267 		return;
2268 
2269 	dmi_check_system(multi_dmi_table);
2270 	multi_checked = 1;
2271 }
2272 
2273 /*
2274  * apic_is_clustered_box() -- Check if we can expect good TSC
2275  *
2276  * Thus far, the major user of this is IBM's Summit2 series:
2277  * Clustered boxes may have unsynced TSC problems if they are
2278  * multi-chassis.
2279  * Use DMI to check them
2280  */
2281 __cpuinit int apic_is_clustered_box(void)
2282 {
2283 	dmi_check_multi();
2284 	if (multi)
2285 		return 1;
2286 
2287 	if (!is_vsmp_box())
2288 		return 0;
2289 
2290 	/*
2291 	 * ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2292 	 * not guaranteed to be synced between boards
2293 	 */
2294 	if (apic_cluster_num() > 1)
2295 		return 1;
2296 
2297 	return 0;
2298 }
2299 #endif
2300 
2301 /*
2302  * APIC command line parameters
2303  */
2304 static int __init setup_disableapic(char *arg)
2305 {
2306 	disable_apic = 1;
2307 	setup_clear_cpu_cap(X86_FEATURE_APIC);
2308 	return 0;
2309 }
2310 early_param("disableapic", setup_disableapic);
2311 
2312 /* same as disableapic, for compatibility */
2313 static int __init setup_nolapic(char *arg)
2314 {
2315 	return setup_disableapic(arg);
2316 }
2317 early_param("nolapic", setup_nolapic);
2318 
2319 static int __init parse_lapic_timer_c2_ok(char *arg)
2320 {
2321 	local_apic_timer_c2_ok = 1;
2322 	return 0;
2323 }
2324 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2325 
2326 static int __init parse_disable_apic_timer(char *arg)
2327 {
2328 	disable_apic_timer = 1;
2329 	return 0;
2330 }
2331 early_param("noapictimer", parse_disable_apic_timer);
2332 
2333 static int __init parse_nolapic_timer(char *arg)
2334 {
2335 	disable_apic_timer = 1;
2336 	return 0;
2337 }
2338 early_param("nolapic_timer", parse_nolapic_timer);
2339 
2340 static int __init apic_set_verbosity(char *arg)
2341 {
2342 	if (!arg)  {
2343 #ifdef CONFIG_X86_64
2344 		skip_ioapic_setup = 0;
2345 		return 0;
2346 #endif
2347 		return -EINVAL;
2348 	}
2349 
2350 	if (strcmp("debug", arg) == 0)
2351 		apic_verbosity = APIC_DEBUG;
2352 	else if (strcmp("verbose", arg) == 0)
2353 		apic_verbosity = APIC_VERBOSE;
2354 	else {
2355 		pr_warning("APIC Verbosity level %s not recognised"
2356 			" use apic=verbose or apic=debug\n", arg);
2357 		return -EINVAL;
2358 	}
2359 
2360 	return 0;
2361 }
2362 early_param("apic", apic_set_verbosity);
2363 
2364 static int __init lapic_insert_resource(void)
2365 {
2366 	if (!apic_phys)
2367 		return -1;
2368 
2369 	/* Put local APIC into the resource map. */
2370 	lapic_resource.start = apic_phys;
2371 	lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2372 	insert_resource(&iomem_resource, &lapic_resource);
2373 
2374 	return 0;
2375 }
2376 
2377 /*
2378  * need call insert after e820_reserve_resources()
2379  * that is using request_resource
2380  */
2381 late_initcall(lapic_insert_resource);
2382