2 * Local APIC handling, local APIC timers
4 * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
7 * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
8 * thanks to Eric Gilmore
10 * for testing these extensively.
11 * Maciej W. Rozycki : Various updates and fixes.
12 * Mikael Pettersson : Power Management for UP-APIC.
14 * Mikael Pettersson : PM converted to driver model.
17 #include <linux/kernel_stat.h>
18 #include <linux/mc146818rtc.h>
19 #include <linux/acpi_pmtmr.h>
20 #include <linux/clockchips.h>
21 #include <linux/interrupt.h>
22 #include <linux/bootmem.h>
23 #include <linux/ftrace.h>
24 #include <linux/ioport.h>
25 #include <linux/module.h>
26 #include <linux/sysdev.h>
27 #include <linux/delay.h>
28 #include <linux/timex.h>
29 #include <linux/dmar.h>
30 #include <linux/init.h>
31 #include <linux/cpu.h>
32 #include <linux/dmi.h>
33 #include <linux/nmi.h>
34 #include <linux/smp.h>
37 #include <asm/arch_hooks.h>
38 #include <asm/pgalloc.h>
39 #include <asm/genapic.h>
40 #include <asm/atomic.h>
41 #include <asm/mpspec.h>
42 #include <asm/i8253.h>
43 #include <asm/i8259.h>
44 #include <asm/proto.h>
52 unsigned int num_processors;
54 unsigned disabled_cpus __cpuinitdata;
56 /* Processor that is doing the boot up */
57 unsigned int boot_cpu_physical_apicid = -1U;
60 * The highest APIC ID seen during enumeration.
62 * This determines the messaging protocol we can use: if all APIC IDs
63 * are in the 0 ... 7 range, then we can use logical addressing which
64 * has some performance advantages (better broadcasting).
66 * If there's an APIC ID above 8, we use physical addressing.
68 unsigned int max_physical_apicid;
71 * Bitmask of physically existing CPUs:
73 physid_mask_t phys_cpu_present_map;
76 * Map cpu index to physical APIC ID
78 DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
79 DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
80 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
81 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
85 * Knob to control our willingness to enable the local APIC.
89 static int force_enable_local_apic;
91 * APIC command line parameters
93 static int __init parse_lapic(char *arg)
95 force_enable_local_apic = 1;
98 early_param("lapic", parse_lapic);
99 /* Local APIC was disabled by the BIOS and enabled by the kernel */
100 static int enabled_via_apicbase;
105 static int apic_calibrate_pmtmr __initdata;
106 static __init int setup_apicpmtimer(char *s)
108 apic_calibrate_pmtmr = 1;
112 __setup("apicpmtimer", setup_apicpmtimer);
115 #ifdef CONFIG_X86_X2APIC
117 /* x2apic enabled before OS handover */
118 static int x2apic_preenabled;
119 static int disable_x2apic;
120 static __init int setup_nox2apic(char *str)
123 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
126 early_param("nox2apic", setup_nox2apic);
129 unsigned long mp_lapic_addr;
131 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
132 static int disable_apic_timer __cpuinitdata;
133 /* Local APIC timer works in C2 */
134 int local_apic_timer_c2_ok;
135 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
137 int first_system_vector = 0xfe;
140 * Debug level, exported for io_apic.c
142 unsigned int apic_verbosity;
146 /* Have we found an MP table */
147 int smp_found_config;
149 static struct resource lapic_resource = {
150 .name = "Local APIC",
151 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
154 static unsigned int calibration_result;
156 static int lapic_next_event(unsigned long delta,
157 struct clock_event_device *evt);
158 static void lapic_timer_setup(enum clock_event_mode mode,
159 struct clock_event_device *evt);
160 static void lapic_timer_broadcast(const struct cpumask *mask);
161 static void apic_pm_activate(void);
164 * The local apic timer can be used for any function which is CPU local.
166 static struct clock_event_device lapic_clockevent = {
168 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
169 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
171 .set_mode = lapic_timer_setup,
172 .set_next_event = lapic_next_event,
173 .broadcast = lapic_timer_broadcast,
177 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
179 static unsigned long apic_phys;
182 * Get the LAPIC version
184 static inline int lapic_get_version(void)
186 return GET_APIC_VERSION(apic_read(APIC_LVR));
190 * Check, if the APIC is integrated or a separate chip
192 static inline int lapic_is_integrated(void)
197 return APIC_INTEGRATED(lapic_get_version());
202 * Check, whether this is a modern or a first generation APIC
204 static int modern_apic(void)
206 /* AMD systems use old APIC versions, so check the CPU */
207 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
208 boot_cpu_data.x86 >= 0xf)
210 return lapic_get_version() >= 0x14;
213 void native_apic_wait_icr_idle(void)
215 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
219 u32 native_safe_apic_wait_icr_idle(void)
226 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
230 } while (timeout++ < 1000);
235 void native_apic_icr_write(u32 low, u32 id)
237 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
238 apic_write(APIC_ICR, low);
241 u64 native_apic_icr_read(void)
245 icr2 = apic_read(APIC_ICR2);
246 icr1 = apic_read(APIC_ICR);
248 return icr1 | ((u64)icr2 << 32);
252 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
254 void __cpuinit enable_NMI_through_LVT0(void)
258 /* unmask and set to NMI */
261 /* Level triggered for 82489DX (32bit mode) */
262 if (!lapic_is_integrated())
263 v |= APIC_LVT_LEVEL_TRIGGER;
265 apic_write(APIC_LVT0, v);
270 * get_physical_broadcast - Get number of physical broadcast IDs
272 int get_physical_broadcast(void)
274 return modern_apic() ? 0xff : 0xf;
279 * lapic_get_maxlvt - get the maximum number of local vector table entries
281 int lapic_get_maxlvt(void)
285 v = apic_read(APIC_LVR);
287 * - we always have APIC integrated on 64bit mode
288 * - 82489DXs do not report # of LVT entries
290 return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
298 #define APIC_DIVISOR 16
301 * This function sets up the local APIC timer, with a timeout of
302 * 'clocks' APIC bus clock. During calibration we actually call
303 * this function twice on the boot CPU, once with a bogus timeout
304 * value, second time for real. The other (noncalibrating) CPUs
305 * call this function only once, with the real, calibrated value.
307 * We do reads before writes even if unnecessary, to get around the
308 * P5 APIC double write bug.
310 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
312 unsigned int lvtt_value, tmp_value;
314 lvtt_value = LOCAL_TIMER_VECTOR;
316 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
317 if (!lapic_is_integrated())
318 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
321 lvtt_value |= APIC_LVT_MASKED;
323 apic_write(APIC_LVTT, lvtt_value);
328 tmp_value = apic_read(APIC_TDCR);
329 apic_write(APIC_TDCR,
330 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
334 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
338 * Setup extended LVT, AMD specific (K8, family 10h)
340 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
341 * MCE interrupts are supported. Thus MCE offset must be set to 0.
343 * If mask=1, the LVT entry does not generate interrupts while mask=0
344 * enables the vector. See also the BKDGs.
347 #define APIC_EILVT_LVTOFF_MCE 0
348 #define APIC_EILVT_LVTOFF_IBS 1
350 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
352 unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
353 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
358 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
360 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
361 return APIC_EILVT_LVTOFF_MCE;
364 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
366 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
367 return APIC_EILVT_LVTOFF_IBS;
369 EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
372 * Program the next event, relative to now
374 static int lapic_next_event(unsigned long delta,
375 struct clock_event_device *evt)
377 apic_write(APIC_TMICT, delta);
382 * Setup the lapic timer in periodic or oneshot mode
384 static void lapic_timer_setup(enum clock_event_mode mode,
385 struct clock_event_device *evt)
390 /* Lapic used as dummy for broadcast ? */
391 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
394 local_irq_save(flags);
397 case CLOCK_EVT_MODE_PERIODIC:
398 case CLOCK_EVT_MODE_ONESHOT:
399 __setup_APIC_LVTT(calibration_result,
400 mode != CLOCK_EVT_MODE_PERIODIC, 1);
402 case CLOCK_EVT_MODE_UNUSED:
403 case CLOCK_EVT_MODE_SHUTDOWN:
404 v = apic_read(APIC_LVTT);
405 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
406 apic_write(APIC_LVTT, v);
407 apic_write(APIC_TMICT, 0xffffffff);
409 case CLOCK_EVT_MODE_RESUME:
410 /* Nothing to do here */
414 local_irq_restore(flags);
418 * Local APIC timer broadcast function
420 static void lapic_timer_broadcast(const struct cpumask *mask)
423 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
428 * Setup the local APIC timer for this CPU. Copy the initilized values
429 * of the boot CPU and register the clock event in the framework.
431 static void __cpuinit setup_APIC_timer(void)
433 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
435 memcpy(levt, &lapic_clockevent, sizeof(*levt));
436 levt->cpumask = cpumask_of(smp_processor_id());
438 clockevents_register_device(levt);
442 * In this functions we calibrate APIC bus clocks to the external timer.
444 * We want to do the calibration only once since we want to have local timer
445 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
448 * This was previously done by reading the PIT/HPET and waiting for a wrap
449 * around to find out, that a tick has elapsed. I have a box, where the PIT
450 * readout is broken, so it never gets out of the wait loop again. This was
451 * also reported by others.
453 * Monitoring the jiffies value is inaccurate and the clockevents
454 * infrastructure allows us to do a simple substitution of the interrupt
457 * The calibration routine also uses the pm_timer when possible, as the PIT
458 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
459 * back to normal later in the boot process).
462 #define LAPIC_CAL_LOOPS (HZ/10)
464 static __initdata int lapic_cal_loops = -1;
465 static __initdata long lapic_cal_t1, lapic_cal_t2;
466 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
467 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
468 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
471 * Temporary interrupt handler.
473 static void __init lapic_cal_handler(struct clock_event_device *dev)
475 unsigned long long tsc = 0;
476 long tapic = apic_read(APIC_TMCCT);
477 unsigned long pm = acpi_pm_read_early();
482 switch (lapic_cal_loops++) {
484 lapic_cal_t1 = tapic;
485 lapic_cal_tsc1 = tsc;
487 lapic_cal_j1 = jiffies;
490 case LAPIC_CAL_LOOPS:
491 lapic_cal_t2 = tapic;
492 lapic_cal_tsc2 = tsc;
493 if (pm < lapic_cal_pm1)
494 pm += ACPI_PM_OVRRUN;
496 lapic_cal_j2 = jiffies;
502 calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
504 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
505 const long pm_thresh = pm_100ms / 100;
509 #ifndef CONFIG_X86_PM_TIMER
513 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
515 /* Check, if the PM timer is available */
519 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
521 if (deltapm > (pm_100ms - pm_thresh) &&
522 deltapm < (pm_100ms + pm_thresh)) {
523 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
527 res = (((u64)deltapm) * mult) >> 22;
528 do_div(res, 1000000);
529 pr_warning("APIC calibration not consistent "
530 "with PM-Timer: %ldms instead of 100ms\n",(long)res);
532 /* Correct the lapic counter value */
533 res = (((u64)(*delta)) * pm_100ms);
534 do_div(res, deltapm);
535 pr_info("APIC delta adjusted to PM-Timer: "
536 "%lu (%ld)\n", (unsigned long)res, *delta);
539 /* Correct the tsc counter value */
541 res = (((u64)(*deltatsc)) * pm_100ms);
542 do_div(res, deltapm);
543 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
544 "PM-Timer: %lu (%ld) \n",
545 (unsigned long)res, *deltatsc);
546 *deltatsc = (long)res;
552 static int __init calibrate_APIC_clock(void)
554 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
555 void (*real_handler)(struct clock_event_device *dev);
556 unsigned long deltaj;
557 long delta, deltatsc;
558 int pm_referenced = 0;
562 /* Replace the global interrupt handler */
563 real_handler = global_clock_event->event_handler;
564 global_clock_event->event_handler = lapic_cal_handler;
567 * Setup the APIC counter to maximum. There is no way the lapic
568 * can underflow in the 100ms detection time frame
570 __setup_APIC_LVTT(0xffffffff, 0, 0);
572 /* Let the interrupts run */
575 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
580 /* Restore the real event handler */
581 global_clock_event->event_handler = real_handler;
583 /* Build delta t1-t2 as apic timer counts down */
584 delta = lapic_cal_t1 - lapic_cal_t2;
585 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
587 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
589 /* we trust the PM based calibration if possible */
590 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
593 /* Calculate the scaled math multiplication factor */
594 lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
595 lapic_clockevent.shift);
596 lapic_clockevent.max_delta_ns =
597 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
598 lapic_clockevent.min_delta_ns =
599 clockevent_delta2ns(0xF, &lapic_clockevent);
601 calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
603 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
604 apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
605 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
609 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
611 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
612 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
615 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
617 calibration_result / (1000000 / HZ),
618 calibration_result % (1000000 / HZ));
621 * Do a sanity check on the APIC calibration result
623 if (calibration_result < (1000000 / HZ)) {
625 pr_warning("APIC frequency too slow, disabling apic timer\n");
629 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
632 * PM timer calibration failed or not turned on
633 * so lets try APIC timer based calibration
635 if (!pm_referenced) {
636 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
639 * Setup the apic timer manually
641 levt->event_handler = lapic_cal_handler;
642 lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
643 lapic_cal_loops = -1;
645 /* Let the interrupts run */
648 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
651 /* Stop the lapic timer */
652 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
655 deltaj = lapic_cal_j2 - lapic_cal_j1;
656 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
658 /* Check, if the jiffies result is consistent */
659 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
660 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
662 levt->features |= CLOCK_EVT_FEAT_DUMMY;
666 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
667 pr_warning("APIC timer disabled due to verification failure\n");
675 * Setup the boot APIC
677 * Calibrate and verify the result.
679 void __init setup_boot_APIC_clock(void)
682 * The local apic timer can be disabled via the kernel
683 * commandline or from the CPU detection code. Register the lapic
684 * timer as a dummy clock event source on SMP systems, so the
685 * broadcast mechanism is used. On UP systems simply ignore it.
687 if (disable_apic_timer) {
688 pr_info("Disabling APIC timer\n");
689 /* No broadcast on UP ! */
690 if (num_possible_cpus() > 1) {
691 lapic_clockevent.mult = 1;
697 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
698 "calibrating APIC timer ...\n");
700 if (calibrate_APIC_clock()) {
701 /* No broadcast on UP ! */
702 if (num_possible_cpus() > 1)
708 * If nmi_watchdog is set to IO_APIC, we need the
709 * PIT/HPET going. Otherwise register lapic as a dummy
712 if (nmi_watchdog != NMI_IO_APIC)
713 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
715 pr_warning("APIC timer registered as dummy,"
716 " due to nmi_watchdog=%d!\n", nmi_watchdog);
718 /* Setup the lapic or request the broadcast */
722 void __cpuinit setup_secondary_APIC_clock(void)
728 * The guts of the apic timer interrupt
730 static void local_apic_timer_interrupt(void)
732 int cpu = smp_processor_id();
733 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
736 * Normally we should not be here till LAPIC has been initialized but
737 * in some cases like kdump, its possible that there is a pending LAPIC
738 * timer interrupt from previous kernel's context and is delivered in
739 * new kernel the moment interrupts are enabled.
741 * Interrupts are enabled early and LAPIC is setup much later, hence
742 * its possible that when we get here evt->event_handler is NULL.
743 * Check for event_handler being NULL and discard the interrupt as
746 if (!evt->event_handler) {
747 pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
749 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
754 * the NMI deadlock-detector uses this.
756 inc_irq_stat(apic_timer_irqs);
758 evt->event_handler(evt);
762 * Local APIC timer interrupt. This is the most natural way for doing
763 * local interrupts, but local timer interrupts can be emulated by
764 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
766 * [ if a single-CPU system runs an SMP kernel then we call the local
767 * interrupt as well. Thus we cannot inline the local irq ... ]
769 void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
771 struct pt_regs *old_regs = set_irq_regs(regs);
774 * NOTE! We'd better ACK the irq immediately,
775 * because timer handling can be slow.
779 * update_process_times() expects us to have done irq_enter().
780 * Besides, if we don't timer interrupts ignore the global
781 * interrupt lock, which is the WrongThing (tm) to do.
785 local_apic_timer_interrupt();
788 set_irq_regs(old_regs);
791 int setup_profiling_timer(unsigned int multiplier)
797 * Local APIC start and shutdown
801 * clear_local_APIC - shutdown the local APIC
803 * This is called, when a CPU is disabled and before rebooting, so the state of
804 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
805 * leftovers during boot.
807 void clear_local_APIC(void)
812 /* APIC hasn't been mapped yet */
816 maxlvt = lapic_get_maxlvt();
818 * Masking an LVT entry can trigger a local APIC error
819 * if the vector is zero. Mask LVTERR first to prevent this.
822 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
823 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
826 * Careful: we have to set masks only first to deassert
827 * any level-triggered sources.
829 v = apic_read(APIC_LVTT);
830 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
831 v = apic_read(APIC_LVT0);
832 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
833 v = apic_read(APIC_LVT1);
834 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
836 v = apic_read(APIC_LVTPC);
837 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
840 /* lets not touch this if we didn't frob it */
841 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(X86_MCE_INTEL)
843 v = apic_read(APIC_LVTTHMR);
844 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
848 * Clean APIC state for other OSs:
850 apic_write(APIC_LVTT, APIC_LVT_MASKED);
851 apic_write(APIC_LVT0, APIC_LVT_MASKED);
852 apic_write(APIC_LVT1, APIC_LVT_MASKED);
854 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
856 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
858 /* Integrated APIC (!82489DX) ? */
859 if (lapic_is_integrated()) {
861 /* Clear ESR due to Pentium errata 3AP and 11AP */
862 apic_write(APIC_ESR, 0);
868 * disable_local_APIC - clear and disable the local APIC
870 void disable_local_APIC(void)
874 /* APIC hasn't been mapped yet */
881 * Disable APIC (implies clearing of registers
884 value = apic_read(APIC_SPIV);
885 value &= ~APIC_SPIV_APIC_ENABLED;
886 apic_write(APIC_SPIV, value);
890 * When LAPIC was disabled by the BIOS and enabled by the kernel,
891 * restore the disabled state.
893 if (enabled_via_apicbase) {
896 rdmsr(MSR_IA32_APICBASE, l, h);
897 l &= ~MSR_IA32_APICBASE_ENABLE;
898 wrmsr(MSR_IA32_APICBASE, l, h);
904 * If Linux enabled the LAPIC against the BIOS default disable it down before
905 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
906 * not power-off. Additionally clear all LVT entries before disable_local_APIC
907 * for the case where Linux didn't enable the LAPIC.
909 void lapic_shutdown(void)
916 local_irq_save(flags);
919 if (!enabled_via_apicbase)
923 disable_local_APIC();
926 local_irq_restore(flags);
930 * This is to verify that we're looking at a real local APIC.
931 * Check these against your board if the CPUs aren't getting
932 * started for no apparent reason.
934 int __init verify_local_APIC(void)
936 unsigned int reg0, reg1;
939 * The version register is read-only in a real APIC.
941 reg0 = apic_read(APIC_LVR);
942 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
943 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
944 reg1 = apic_read(APIC_LVR);
945 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
948 * The two version reads above should print the same
949 * numbers. If the second one is different, then we
950 * poke at a non-APIC.
956 * Check if the version looks reasonably.
958 reg1 = GET_APIC_VERSION(reg0);
959 if (reg1 == 0x00 || reg1 == 0xff)
961 reg1 = lapic_get_maxlvt();
962 if (reg1 < 0x02 || reg1 == 0xff)
966 * The ID register is read/write in a real APIC.
968 reg0 = apic_read(APIC_ID);
969 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
970 apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
971 reg1 = apic_read(APIC_ID);
972 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
973 apic_write(APIC_ID, reg0);
974 if (reg1 != (reg0 ^ apic->apic_id_mask))
978 * The next two are just to see if we have sane values.
979 * They're only really relevant if we're in Virtual Wire
980 * compatibility mode, but most boxes are anymore.
982 reg0 = apic_read(APIC_LVT0);
983 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
984 reg1 = apic_read(APIC_LVT1);
985 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
991 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
993 void __init sync_Arb_IDs(void)
996 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
999 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1005 apic_wait_icr_idle();
1007 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1008 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1009 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1013 * An initial setup of the virtual wire mode.
1015 void __init init_bsp_APIC(void)
1020 * Don't do the setup now if we have a SMP BIOS as the
1021 * through-I/O-APIC virtual wire mode might be active.
1023 if (smp_found_config || !cpu_has_apic)
1027 * Do not trust the local APIC being empty at bootup.
1034 value = apic_read(APIC_SPIV);
1035 value &= ~APIC_VECTOR_MASK;
1036 value |= APIC_SPIV_APIC_ENABLED;
1038 #ifdef CONFIG_X86_32
1039 /* This bit is reserved on P4/Xeon and should be cleared */
1040 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1041 (boot_cpu_data.x86 == 15))
1042 value &= ~APIC_SPIV_FOCUS_DISABLED;
1045 value |= APIC_SPIV_FOCUS_DISABLED;
1046 value |= SPURIOUS_APIC_VECTOR;
1047 apic_write(APIC_SPIV, value);
1050 * Set up the virtual wire mode.
1052 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1053 value = APIC_DM_NMI;
1054 if (!lapic_is_integrated()) /* 82489DX */
1055 value |= APIC_LVT_LEVEL_TRIGGER;
1056 apic_write(APIC_LVT1, value);
1059 static void __cpuinit lapic_setup_esr(void)
1061 unsigned int oldvalue, value, maxlvt;
1063 if (!lapic_is_integrated()) {
1064 pr_info("No ESR for 82489DX.\n");
1068 if (apic->disable_esr) {
1070 * Something untraceable is creating bad interrupts on
1071 * secondary quads ... for the moment, just leave the
1072 * ESR disabled - we can't do anything useful with the
1073 * errors anyway - mbligh
1075 pr_info("Leaving ESR disabled.\n");
1079 maxlvt = lapic_get_maxlvt();
1080 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1081 apic_write(APIC_ESR, 0);
1082 oldvalue = apic_read(APIC_ESR);
1084 /* enables sending errors */
1085 value = ERROR_APIC_VECTOR;
1086 apic_write(APIC_LVTERR, value);
1089 * spec says clear errors after enabling vector.
1092 apic_write(APIC_ESR, 0);
1093 value = apic_read(APIC_ESR);
1094 if (value != oldvalue)
1095 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1096 "vector: 0x%08x after: 0x%08x\n",
1102 * setup_local_APIC - setup the local APIC
1104 void __cpuinit setup_local_APIC(void)
1110 arch_disable_smp_support();
1114 #ifdef CONFIG_X86_32
1115 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1116 if (lapic_is_integrated() && apic->disable_esr) {
1117 apic_write(APIC_ESR, 0);
1118 apic_write(APIC_ESR, 0);
1119 apic_write(APIC_ESR, 0);
1120 apic_write(APIC_ESR, 0);
1127 * Double-check whether this APIC is really registered.
1128 * This is meaningless in clustered apic mode, so we skip it.
1130 if (!apic->apic_id_registered())
1134 * Intel recommends to set DFR, LDR and TPR before enabling
1135 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1136 * document number 292116). So here it goes...
1138 apic->init_apic_ldr();
1141 * Set Task Priority to 'accept all'. We never change this
1144 value = apic_read(APIC_TASKPRI);
1145 value &= ~APIC_TPRI_MASK;
1146 apic_write(APIC_TASKPRI, value);
1149 * After a crash, we no longer service the interrupts and a pending
1150 * interrupt from previous kernel might still have ISR bit set.
1152 * Most probably by now CPU has serviced that pending interrupt and
1153 * it might not have done the ack_APIC_irq() because it thought,
1154 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1155 * does not clear the ISR bit and cpu thinks it has already serivced
1156 * the interrupt. Hence a vector might get locked. It was noticed
1157 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1159 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1160 value = apic_read(APIC_ISR + i*0x10);
1161 for (j = 31; j >= 0; j--) {
1168 * Now that we are all set up, enable the APIC
1170 value = apic_read(APIC_SPIV);
1171 value &= ~APIC_VECTOR_MASK;
1175 value |= APIC_SPIV_APIC_ENABLED;
1177 #ifdef CONFIG_X86_32
1179 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1180 * certain networking cards. If high frequency interrupts are
1181 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1182 * entry is masked/unmasked at a high rate as well then sooner or
1183 * later IOAPIC line gets 'stuck', no more interrupts are received
1184 * from the device. If focus CPU is disabled then the hang goes
1187 * [ This bug can be reproduced easily with a level-triggered
1188 * PCI Ne2000 networking cards and PII/PIII processors, dual
1192 * Actually disabling the focus CPU check just makes the hang less
1193 * frequent as it makes the interrupt distributon model be more
1194 * like LRU than MRU (the short-term load is more even across CPUs).
1195 * See also the comment in end_level_ioapic_irq(). --macro
1199 * - enable focus processor (bit==0)
1200 * - 64bit mode always use processor focus
1201 * so no need to set it
1203 value &= ~APIC_SPIV_FOCUS_DISABLED;
1207 * Set spurious IRQ vector
1209 value |= SPURIOUS_APIC_VECTOR;
1210 apic_write(APIC_SPIV, value);
1213 * Set up LVT0, LVT1:
1215 * set up through-local-APIC on the BP's LINT0. This is not
1216 * strictly necessary in pure symmetric-IO mode, but sometimes
1217 * we delegate interrupts to the 8259A.
1220 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1222 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1223 if (!smp_processor_id() && (pic_mode || !value)) {
1224 value = APIC_DM_EXTINT;
1225 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1226 smp_processor_id());
1228 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1229 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1230 smp_processor_id());
1232 apic_write(APIC_LVT0, value);
1235 * only the BP should see the LINT1 NMI signal, obviously.
1237 if (!smp_processor_id())
1238 value = APIC_DM_NMI;
1240 value = APIC_DM_NMI | APIC_LVT_MASKED;
1241 if (!lapic_is_integrated()) /* 82489DX */
1242 value |= APIC_LVT_LEVEL_TRIGGER;
1243 apic_write(APIC_LVT1, value);
1248 void __cpuinit end_local_APIC_setup(void)
1252 #ifdef CONFIG_X86_32
1255 /* Disable the local apic timer */
1256 value = apic_read(APIC_LVTT);
1257 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1258 apic_write(APIC_LVTT, value);
1262 setup_apic_nmi_watchdog(NULL);
1266 #ifdef CONFIG_X86_X2APIC
1267 void check_x2apic(void)
1271 if (!cpu_has_x2apic)
1274 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1276 if (msr & X2APIC_ENABLE) {
1277 pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
1278 x2apic_preenabled = x2apic = 1;
1282 void enable_x2apic(void)
1289 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1290 if (!(msr & X2APIC_ENABLE)) {
1291 pr_info("Enabling x2apic\n");
1292 wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1296 void __init enable_IR_x2apic(void)
1298 #ifdef CONFIG_INTR_REMAP
1300 unsigned long flags;
1302 if (!cpu_has_x2apic)
1305 if (!x2apic_preenabled && disable_x2apic) {
1306 pr_info("Skipped enabling x2apic and Interrupt-remapping "
1307 "because of nox2apic\n");
1311 if (x2apic_preenabled && disable_x2apic)
1312 panic("Bios already enabled x2apic, can't enforce nox2apic");
1314 if (!x2apic_preenabled && skip_ioapic_setup) {
1315 pr_info("Skipped enabling x2apic and Interrupt-remapping "
1316 "because of skipping io-apic setup\n");
1320 ret = dmar_table_init();
1322 pr_info("dmar_table_init() failed with %d:\n", ret);
1324 if (x2apic_preenabled)
1325 panic("x2apic enabled by bios. But IR enabling failed");
1327 pr_info("Not enabling x2apic,Intr-remapping\n");
1331 local_irq_save(flags);
1334 ret = save_mask_IO_APIC_setup();
1336 pr_info("Saving IO-APIC state failed: %d\n", ret);
1340 ret = enable_intr_remapping(1);
1342 if (ret && x2apic_preenabled) {
1343 local_irq_restore(flags);
1344 panic("x2apic enabled by bios. But IR enabling failed");
1358 * IR enabling failed
1360 restore_IO_APIC_setup();
1362 reinit_intr_remapped_IO_APIC(x2apic_preenabled);
1366 local_irq_restore(flags);
1369 if (!x2apic_preenabled)
1370 pr_info("Enabled x2apic and interrupt-remapping\n");
1372 pr_info("Enabled Interrupt-remapping\n");
1374 pr_err("Failed to enable Interrupt-remapping and x2apic\n");
1376 if (!cpu_has_x2apic)
1379 if (x2apic_preenabled)
1380 panic("x2apic enabled prior OS handover,"
1381 " enable CONFIG_INTR_REMAP");
1383 pr_info("Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1389 #endif /* CONFIG_X86_X2APIC */
1391 #ifdef CONFIG_X86_64
1393 * Detect and enable local APICs on non-SMP boards.
1394 * Original code written by Keir Fraser.
1395 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1396 * not correctly set up (usually the APIC timer won't work etc.)
1398 static int __init detect_init_APIC(void)
1400 if (!cpu_has_apic) {
1401 pr_info("No local APIC present\n");
1405 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1406 boot_cpu_physical_apicid = 0;
1411 * Detect and initialize APIC
1413 static int __init detect_init_APIC(void)
1417 /* Disabled by kernel option? */
1421 switch (boot_cpu_data.x86_vendor) {
1422 case X86_VENDOR_AMD:
1423 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1424 (boot_cpu_data.x86 >= 15))
1427 case X86_VENDOR_INTEL:
1428 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1429 (boot_cpu_data.x86 == 5 && cpu_has_apic))
1436 if (!cpu_has_apic) {
1438 * Over-ride BIOS and try to enable the local APIC only if
1439 * "lapic" specified.
1441 if (!force_enable_local_apic) {
1442 pr_info("Local APIC disabled by BIOS -- "
1443 "you can enable it with \"lapic\"\n");
1447 * Some BIOSes disable the local APIC in the APIC_BASE
1448 * MSR. This can only be done in software for Intel P6 or later
1449 * and AMD K7 (Model > 1) or later.
1451 rdmsr(MSR_IA32_APICBASE, l, h);
1452 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1453 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1454 l &= ~MSR_IA32_APICBASE_BASE;
1455 l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
1456 wrmsr(MSR_IA32_APICBASE, l, h);
1457 enabled_via_apicbase = 1;
1461 * The APIC feature bit should now be enabled
1464 features = cpuid_edx(1);
1465 if (!(features & (1 << X86_FEATURE_APIC))) {
1466 pr_warning("Could not enable APIC!\n");
1469 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1470 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1472 /* The BIOS may have set up the APIC at some other address */
1473 rdmsr(MSR_IA32_APICBASE, l, h);
1474 if (l & MSR_IA32_APICBASE_ENABLE)
1475 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1477 pr_info("Found and enabled local APIC!\n");
1484 pr_info("No local APIC present or hardware disabled\n");
1489 #ifdef CONFIG_X86_64
1490 void __init early_init_lapic_mapping(void)
1492 unsigned long phys_addr;
1495 * If no local APIC can be found then go out
1496 * : it means there is no mpatable and MADT
1498 if (!smp_found_config)
1501 phys_addr = mp_lapic_addr;
1503 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1504 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1505 APIC_BASE, phys_addr);
1508 * Fetch the APIC ID of the BSP in case we have a
1509 * default configuration (or the MP table is broken).
1511 boot_cpu_physical_apicid = read_apic_id();
1516 * init_apic_mappings - initialize APIC mappings
1518 void __init init_apic_mappings(void)
1520 #ifdef CONFIG_X86_X2APIC
1522 boot_cpu_physical_apicid = read_apic_id();
1528 * If no local APIC can be found then set up a fake all
1529 * zeroes page to simulate the local APIC and another
1530 * one for the IO-APIC.
1532 if (!smp_found_config && detect_init_APIC()) {
1533 apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
1534 apic_phys = __pa(apic_phys);
1536 apic_phys = mp_lapic_addr;
1538 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1539 apic_printk(APIC_VERBOSE, "mapped APIC to %08lx (%08lx)\n",
1540 APIC_BASE, apic_phys);
1543 * Fetch the APIC ID of the BSP in case we have a
1544 * default configuration (or the MP table is broken).
1546 if (boot_cpu_physical_apicid == -1U)
1547 boot_cpu_physical_apicid = read_apic_id();
1551 * This initializes the IO-APIC and APIC hardware if this is
1554 int apic_version[MAX_APICS];
1556 int __init APIC_init_uniprocessor(void)
1559 pr_info("Apic disabled\n");
1562 #ifdef CONFIG_X86_64
1563 if (!cpu_has_apic) {
1565 pr_info("Apic disabled by BIOS\n");
1569 if (!smp_found_config && !cpu_has_apic)
1573 * Complain if the BIOS pretends there is one.
1575 if (!cpu_has_apic &&
1576 APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1577 pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
1578 boot_cpu_physical_apicid);
1579 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1585 #ifdef CONFIG_X86_64
1586 default_setup_apic_routing();
1589 verify_local_APIC();
1592 #ifdef CONFIG_X86_64
1593 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1596 * Hack: In case of kdump, after a crash, kernel might be booting
1597 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1598 * might be zero if read from MP tables. Get it from LAPIC.
1600 # ifdef CONFIG_CRASH_DUMP
1601 boot_cpu_physical_apicid = read_apic_id();
1604 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1607 #ifdef CONFIG_X86_IO_APIC
1609 * Now enable IO-APICs, actually call clear_IO_APIC
1610 * We need clear_IO_APIC before enabling error vector
1612 if (!skip_ioapic_setup && nr_ioapics)
1616 end_local_APIC_setup();
1618 #ifdef CONFIG_X86_IO_APIC
1619 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1623 localise_nmi_watchdog();
1626 localise_nmi_watchdog();
1630 #ifdef CONFIG_X86_64
1631 check_nmi_watchdog();
1638 * Local APIC interrupts
1642 * This interrupt should _never_ happen with our APIC/SMP architecture
1644 void smp_spurious_interrupt(struct pt_regs *regs)
1651 * Check if this really is a spurious interrupt and ACK it
1652 * if it is a vectored one. Just in case...
1653 * Spurious interrupts should not be ACKed.
1655 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1656 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1659 inc_irq_stat(irq_spurious_count);
1661 /* see sw-dev-man vol 3, chapter 7.4.13.5 */
1662 pr_info("spurious APIC interrupt on CPU#%d, "
1663 "should never happen.\n", smp_processor_id());
1668 * This interrupt should never happen with our APIC/SMP architecture
1670 void smp_error_interrupt(struct pt_regs *regs)
1676 /* First tickle the hardware, only then report what went on. -- REW */
1677 v = apic_read(APIC_ESR);
1678 apic_write(APIC_ESR, 0);
1679 v1 = apic_read(APIC_ESR);
1681 atomic_inc(&irq_err_count);
1684 * Here is what the APIC error bits mean:
1686 * 1: Receive CS error
1687 * 2: Send accept error
1688 * 3: Receive accept error
1690 * 5: Send illegal vector
1691 * 6: Received illegal vector
1692 * 7: Illegal register address
1694 pr_debug("APIC error on CPU%d: %02x(%02x)\n",
1695 smp_processor_id(), v , v1);
1700 * connect_bsp_APIC - attach the APIC to the interrupt system
1702 void __init connect_bsp_APIC(void)
1704 #ifdef CONFIG_X86_32
1707 * Do not trust the local APIC being empty at bootup.
1711 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
1712 * local APIC to INT and NMI lines.
1714 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1715 "enabling APIC mode.\n");
1720 if (apic->enable_apic_mode)
1721 apic->enable_apic_mode();
1725 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1726 * @virt_wire_setup: indicates, whether virtual wire mode is selected
1728 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1731 void disconnect_bsp_APIC(int virt_wire_setup)
1735 #ifdef CONFIG_X86_32
1738 * Put the board back into PIC mode (has an effect only on
1739 * certain older boards). Note that APIC interrupts, including
1740 * IPIs, won't work beyond this point! The only exception are
1743 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1744 "entering PIC mode.\n");
1751 /* Go back to Virtual Wire compatibility mode */
1753 /* For the spurious interrupt use vector F, and enable it */
1754 value = apic_read(APIC_SPIV);
1755 value &= ~APIC_VECTOR_MASK;
1756 value |= APIC_SPIV_APIC_ENABLED;
1758 apic_write(APIC_SPIV, value);
1760 if (!virt_wire_setup) {
1762 * For LVT0 make it edge triggered, active high,
1763 * external and enabled
1765 value = apic_read(APIC_LVT0);
1766 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1767 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1768 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1769 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1770 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1771 apic_write(APIC_LVT0, value);
1774 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1778 * For LVT1 make it edge triggered, active high,
1781 value = apic_read(APIC_LVT1);
1782 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1783 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1784 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1785 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1786 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1787 apic_write(APIC_LVT1, value);
1790 void __cpuinit generic_processor_info(int apicid, int version)
1797 if (version == 0x0) {
1798 pr_warning("BIOS bug, APIC version is 0 for CPU#%d! "
1799 "fixing up to 0x10. (tell your hw vendor)\n",
1803 apic_version[apicid] = version;
1805 if (num_processors >= nr_cpu_ids) {
1806 int max = nr_cpu_ids;
1807 int thiscpu = max + disabled_cpus;
1810 "ACPI: NR_CPUS/possible_cpus limit of %i reached."
1811 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
1818 cpu = cpumask_next_zero(-1, cpu_present_mask);
1820 if (version != apic_version[boot_cpu_physical_apicid])
1822 "ACPI: apic version mismatch, bootcpu: %x cpu %d: %x\n",
1823 apic_version[boot_cpu_physical_apicid], cpu, version);
1825 physid_set(apicid, phys_cpu_present_map);
1826 if (apicid == boot_cpu_physical_apicid) {
1828 * x86_bios_cpu_apicid is required to have processors listed
1829 * in same order as logical cpu numbers. Hence the first
1830 * entry is BSP, and so on.
1834 if (apicid > max_physical_apicid)
1835 max_physical_apicid = apicid;
1837 #ifdef CONFIG_X86_32
1839 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
1840 * but we need to work other dependencies like SMP_SUSPEND etc
1841 * before this can be done without some confusion.
1842 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
1843 * - Ashok Raj <ashok.raj@intel.com>
1845 if (max_physical_apicid >= 8) {
1846 switch (boot_cpu_data.x86_vendor) {
1847 case X86_VENDOR_INTEL:
1848 if (!APIC_XAPIC(version)) {
1852 /* If P4 and above fall through */
1853 case X86_VENDOR_AMD:
1859 #if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
1860 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1861 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1864 set_cpu_possible(cpu, true);
1865 set_cpu_present(cpu, true);
1868 int hard_smp_processor_id(void)
1870 return read_apic_id();
1873 void default_init_apic_ldr(void)
1877 apic_write(APIC_DFR, APIC_DFR_VALUE);
1878 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
1879 val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
1880 apic_write(APIC_LDR, val);
1883 #ifdef CONFIG_X86_32
1884 int default_apicid_to_node(int logical_apicid)
1887 return apicid_2_node[hard_smp_processor_id()];
1901 * 'active' is true if the local APIC was enabled by us and
1902 * not the BIOS; this signifies that we are also responsible
1903 * for disabling it before entering apm/acpi suspend
1906 /* r/w apic fields */
1907 unsigned int apic_id;
1908 unsigned int apic_taskpri;
1909 unsigned int apic_ldr;
1910 unsigned int apic_dfr;
1911 unsigned int apic_spiv;
1912 unsigned int apic_lvtt;
1913 unsigned int apic_lvtpc;
1914 unsigned int apic_lvt0;
1915 unsigned int apic_lvt1;
1916 unsigned int apic_lvterr;
1917 unsigned int apic_tmict;
1918 unsigned int apic_tdcr;
1919 unsigned int apic_thmr;
1922 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1924 unsigned long flags;
1927 if (!apic_pm_state.active)
1930 maxlvt = lapic_get_maxlvt();
1932 apic_pm_state.apic_id = apic_read(APIC_ID);
1933 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1934 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1935 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1936 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1937 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1939 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1940 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1941 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1942 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1943 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1944 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1945 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1947 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1950 local_irq_save(flags);
1951 disable_local_APIC();
1952 local_irq_restore(flags);
1956 static int lapic_resume(struct sys_device *dev)
1959 unsigned long flags;
1962 if (!apic_pm_state.active)
1965 maxlvt = lapic_get_maxlvt();
1967 local_irq_save(flags);
1969 #ifdef CONFIG_X86_X2APIC
1976 * Make sure the APICBASE points to the right address
1978 * FIXME! This will be wrong if we ever support suspend on
1979 * SMP! We'll need to do this as part of the CPU restore!
1981 rdmsr(MSR_IA32_APICBASE, l, h);
1982 l &= ~MSR_IA32_APICBASE_BASE;
1983 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
1984 wrmsr(MSR_IA32_APICBASE, l, h);
1987 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
1988 apic_write(APIC_ID, apic_pm_state.apic_id);
1989 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
1990 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
1991 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
1992 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
1993 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
1994 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
1995 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1997 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2000 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2001 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2002 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2003 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2004 apic_write(APIC_ESR, 0);
2005 apic_read(APIC_ESR);
2006 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2007 apic_write(APIC_ESR, 0);
2008 apic_read(APIC_ESR);
2010 local_irq_restore(flags);
2016 * This device has no shutdown method - fully functioning local APICs
2017 * are needed on every CPU up until machine_halt/restart/poweroff.
2020 static struct sysdev_class lapic_sysclass = {
2022 .resume = lapic_resume,
2023 .suspend = lapic_suspend,
2026 static struct sys_device device_lapic = {
2028 .cls = &lapic_sysclass,
2031 static void __cpuinit apic_pm_activate(void)
2033 apic_pm_state.active = 1;
2036 static int __init init_lapic_sysfs(void)
2042 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2044 error = sysdev_class_register(&lapic_sysclass);
2046 error = sysdev_register(&device_lapic);
2049 device_initcall(init_lapic_sysfs);
2051 #else /* CONFIG_PM */
2053 static void apic_pm_activate(void) { }
2055 #endif /* CONFIG_PM */
2057 #ifdef CONFIG_X86_64
2059 * apic_is_clustered_box() -- Check if we can expect good TSC
2061 * Thus far, the major user of this is IBM's Summit2 series:
2063 * Clustered boxes may have unsynced TSC problems if they are
2064 * multi-chassis. Use available data to take a good guess.
2065 * If in doubt, go HPET.
2067 __cpuinit int apic_is_clustered_box(void)
2069 int i, clusters, zeros;
2071 u16 *bios_cpu_apicid;
2072 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2075 * there is not this kind of box with AMD CPU yet.
2076 * Some AMD box with quadcore cpu and 8 sockets apicid
2077 * will be [4, 0x23] or [8, 0x27] could be thought to
2078 * vsmp box still need checking...
2080 if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
2083 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2084 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2086 for (i = 0; i < nr_cpu_ids; i++) {
2087 /* are we being called early in kernel startup? */
2088 if (bios_cpu_apicid) {
2089 id = bios_cpu_apicid[i];
2090 } else if (i < nr_cpu_ids) {
2092 id = per_cpu(x86_bios_cpu_apicid, i);
2098 if (id != BAD_APICID)
2099 __set_bit(APIC_CLUSTERID(id), clustermap);
2102 /* Problem: Partially populated chassis may not have CPUs in some of
2103 * the APIC clusters they have been allocated. Only present CPUs have
2104 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2105 * Since clusters are allocated sequentially, count zeros only if
2106 * they are bounded by ones.
2110 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2111 if (test_bit(i, clustermap)) {
2112 clusters += 1 + zeros;
2118 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2119 * not guaranteed to be synced between boards
2121 if (is_vsmp_box() && clusters > 1)
2125 * If clusters > 2, then should be multi-chassis.
2126 * May have to revisit this when multi-core + hyperthreaded CPUs come
2127 * out, but AFAIK this will work even for them.
2129 return (clusters > 2);
2134 * APIC command line parameters
2136 static int __init setup_disableapic(char *arg)
2139 setup_clear_cpu_cap(X86_FEATURE_APIC);
2142 early_param("disableapic", setup_disableapic);
2144 /* same as disableapic, for compatibility */
2145 static int __init setup_nolapic(char *arg)
2147 return setup_disableapic(arg);
2149 early_param("nolapic", setup_nolapic);
2151 static int __init parse_lapic_timer_c2_ok(char *arg)
2153 local_apic_timer_c2_ok = 1;
2156 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2158 static int __init parse_disable_apic_timer(char *arg)
2160 disable_apic_timer = 1;
2163 early_param("noapictimer", parse_disable_apic_timer);
2165 static int __init parse_nolapic_timer(char *arg)
2167 disable_apic_timer = 1;
2170 early_param("nolapic_timer", parse_nolapic_timer);
2172 static int __init apic_set_verbosity(char *arg)
2175 #ifdef CONFIG_X86_64
2176 skip_ioapic_setup = 0;
2182 if (strcmp("debug", arg) == 0)
2183 apic_verbosity = APIC_DEBUG;
2184 else if (strcmp("verbose", arg) == 0)
2185 apic_verbosity = APIC_VERBOSE;
2187 pr_warning("APIC Verbosity level %s not recognised"
2188 " use apic=verbose or apic=debug\n", arg);
2194 early_param("apic", apic_set_verbosity);
2196 static int __init lapic_insert_resource(void)
2201 /* Put local APIC into the resource map. */
2202 lapic_resource.start = apic_phys;
2203 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2204 insert_resource(&iomem_resource, &lapic_resource);
2210 * need call insert after e820_reserve_resources()
2211 * that is using request_resource
2213 late_initcall(lapic_insert_resource);