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/perf_counter.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>
38 #include <asm/perf_counter.h>
39 #include <asm/pgalloc.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>
53 unsigned int num_processors;
55 unsigned disabled_cpus __cpuinitdata;
57 /* Processor that is doing the boot up */
58 unsigned int boot_cpu_physical_apicid = -1U;
61 * The highest APIC ID seen during enumeration.
63 * This determines the messaging protocol we can use: if all APIC IDs
64 * are in the 0 ... 7 range, then we can use logical addressing which
65 * has some performance advantages (better broadcasting).
67 * If there's an APIC ID above 8, we use physical addressing.
69 unsigned int max_physical_apicid;
72 * Bitmask of physically existing CPUs:
74 physid_mask_t phys_cpu_present_map;
77 * Map cpu index to physical APIC ID
79 DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
80 DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
81 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
82 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
86 * Knob to control our willingness to enable the local APIC.
90 static int force_enable_local_apic;
92 * APIC command line parameters
94 static int __init parse_lapic(char *arg)
96 force_enable_local_apic = 1;
99 early_param("lapic", parse_lapic);
100 /* Local APIC was disabled by the BIOS and enabled by the kernel */
101 static int enabled_via_apicbase;
104 * Handle interrupt mode configuration register (IMCR).
105 * This register controls whether the interrupt signals
106 * that reach the BSP come from the master PIC or from the
107 * local APIC. Before entering Symmetric I/O Mode, either
108 * the BIOS or the operating system must switch out of
109 * PIC Mode by changing the IMCR.
111 static inline void imcr_pic_to_apic(void)
113 /* select IMCR register */
115 /* NMI and 8259 INTR go through APIC */
119 static inline void imcr_apic_to_pic(void)
121 /* select IMCR register */
123 /* NMI and 8259 INTR go directly to BSP */
129 static int apic_calibrate_pmtmr __initdata;
130 static __init int setup_apicpmtimer(char *s)
132 apic_calibrate_pmtmr = 1;
136 __setup("apicpmtimer", setup_apicpmtimer);
140 #ifdef CONFIG_X86_X2APIC
141 /* x2apic enabled before OS handover */
142 static int x2apic_preenabled;
143 static int disable_x2apic;
144 static __init int setup_nox2apic(char *str)
146 if (x2apic_enabled()) {
147 pr_warning("Bios already enabled x2apic, "
148 "can't enforce nox2apic");
153 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
156 early_param("nox2apic", setup_nox2apic);
159 unsigned long mp_lapic_addr;
161 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
162 static int disable_apic_timer __cpuinitdata;
163 /* Local APIC timer works in C2 */
164 int local_apic_timer_c2_ok;
165 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
167 int first_system_vector = 0xfe;
170 * Debug level, exported for io_apic.c
172 unsigned int apic_verbosity;
176 /* Have we found an MP table */
177 int smp_found_config;
179 static struct resource lapic_resource = {
180 .name = "Local APIC",
181 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
184 static unsigned int calibration_result;
186 static int lapic_next_event(unsigned long delta,
187 struct clock_event_device *evt);
188 static void lapic_timer_setup(enum clock_event_mode mode,
189 struct clock_event_device *evt);
190 static void lapic_timer_broadcast(const struct cpumask *mask);
191 static void apic_pm_activate(void);
194 * The local apic timer can be used for any function which is CPU local.
196 static struct clock_event_device lapic_clockevent = {
198 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
199 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
201 .set_mode = lapic_timer_setup,
202 .set_next_event = lapic_next_event,
203 .broadcast = lapic_timer_broadcast,
207 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
209 static unsigned long apic_phys;
212 * Get the LAPIC version
214 static inline int lapic_get_version(void)
216 return GET_APIC_VERSION(apic_read(APIC_LVR));
220 * Check, if the APIC is integrated or a separate chip
222 static inline int lapic_is_integrated(void)
227 return APIC_INTEGRATED(lapic_get_version());
232 * Check, whether this is a modern or a first generation APIC
234 static int modern_apic(void)
236 /* AMD systems use old APIC versions, so check the CPU */
237 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
238 boot_cpu_data.x86 >= 0xf)
240 return lapic_get_version() >= 0x14;
244 * bare function to substitute write operation
245 * and it's _that_ fast :)
247 static void native_apic_write_dummy(u32 reg, u32 v)
249 WARN_ON_ONCE((cpu_has_apic || !disable_apic));
252 static u32 native_apic_read_dummy(u32 reg)
254 WARN_ON_ONCE((cpu_has_apic && !disable_apic));
259 * right after this call apic->write/read doesn't do anything
260 * note that there is no restore operation it works one way
262 void apic_disable(void)
264 apic->read = native_apic_read_dummy;
265 apic->write = native_apic_write_dummy;
268 void native_apic_wait_icr_idle(void)
270 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
274 u32 native_safe_apic_wait_icr_idle(void)
281 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
285 } while (timeout++ < 1000);
290 void native_apic_icr_write(u32 low, u32 id)
292 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
293 apic_write(APIC_ICR, low);
296 u64 native_apic_icr_read(void)
300 icr2 = apic_read(APIC_ICR2);
301 icr1 = apic_read(APIC_ICR);
303 return icr1 | ((u64)icr2 << 32);
307 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
309 void __cpuinit enable_NMI_through_LVT0(void)
313 /* unmask and set to NMI */
316 /* Level triggered for 82489DX (32bit mode) */
317 if (!lapic_is_integrated())
318 v |= APIC_LVT_LEVEL_TRIGGER;
320 apic_write(APIC_LVT0, v);
325 * get_physical_broadcast - Get number of physical broadcast IDs
327 int get_physical_broadcast(void)
329 return modern_apic() ? 0xff : 0xf;
334 * lapic_get_maxlvt - get the maximum number of local vector table entries
336 int lapic_get_maxlvt(void)
340 v = apic_read(APIC_LVR);
342 * - we always have APIC integrated on 64bit mode
343 * - 82489DXs do not report # of LVT entries
345 return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
353 #define APIC_DIVISOR 16
356 * This function sets up the local APIC timer, with a timeout of
357 * 'clocks' APIC bus clock. During calibration we actually call
358 * this function twice on the boot CPU, once with a bogus timeout
359 * value, second time for real. The other (noncalibrating) CPUs
360 * call this function only once, with the real, calibrated value.
362 * We do reads before writes even if unnecessary, to get around the
363 * P5 APIC double write bug.
365 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
367 unsigned int lvtt_value, tmp_value;
369 lvtt_value = LOCAL_TIMER_VECTOR;
371 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
372 if (!lapic_is_integrated())
373 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
376 lvtt_value |= APIC_LVT_MASKED;
378 apic_write(APIC_LVTT, lvtt_value);
383 tmp_value = apic_read(APIC_TDCR);
384 apic_write(APIC_TDCR,
385 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
389 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
393 * Setup extended LVT, AMD specific (K8, family 10h)
395 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
396 * MCE interrupts are supported. Thus MCE offset must be set to 0.
398 * If mask=1, the LVT entry does not generate interrupts while mask=0
399 * enables the vector. See also the BKDGs.
402 #define APIC_EILVT_LVTOFF_MCE 0
403 #define APIC_EILVT_LVTOFF_IBS 1
405 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
407 unsigned long reg = (lvt_off << 4) + APIC_EILVTn(0);
408 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
413 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
415 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
416 return APIC_EILVT_LVTOFF_MCE;
419 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
421 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
422 return APIC_EILVT_LVTOFF_IBS;
424 EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
427 * Program the next event, relative to now
429 static int lapic_next_event(unsigned long delta,
430 struct clock_event_device *evt)
432 apic_write(APIC_TMICT, delta);
437 * Setup the lapic timer in periodic or oneshot mode
439 static void lapic_timer_setup(enum clock_event_mode mode,
440 struct clock_event_device *evt)
445 /* Lapic used as dummy for broadcast ? */
446 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
449 local_irq_save(flags);
452 case CLOCK_EVT_MODE_PERIODIC:
453 case CLOCK_EVT_MODE_ONESHOT:
454 __setup_APIC_LVTT(calibration_result,
455 mode != CLOCK_EVT_MODE_PERIODIC, 1);
457 case CLOCK_EVT_MODE_UNUSED:
458 case CLOCK_EVT_MODE_SHUTDOWN:
459 v = apic_read(APIC_LVTT);
460 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
461 apic_write(APIC_LVTT, v);
462 apic_write(APIC_TMICT, 0xffffffff);
464 case CLOCK_EVT_MODE_RESUME:
465 /* Nothing to do here */
469 local_irq_restore(flags);
473 * Local APIC timer broadcast function
475 static void lapic_timer_broadcast(const struct cpumask *mask)
478 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
483 * Setup the local APIC timer for this CPU. Copy the initilized values
484 * of the boot CPU and register the clock event in the framework.
486 static void __cpuinit setup_APIC_timer(void)
488 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
490 if (cpu_has(¤t_cpu_data, X86_FEATURE_ARAT)) {
491 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
492 /* Make LAPIC timer preferrable over percpu HPET */
493 lapic_clockevent.rating = 150;
496 memcpy(levt, &lapic_clockevent, sizeof(*levt));
497 levt->cpumask = cpumask_of(smp_processor_id());
499 clockevents_register_device(levt);
503 * In this functions we calibrate APIC bus clocks to the external timer.
505 * We want to do the calibration only once since we want to have local timer
506 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
509 * This was previously done by reading the PIT/HPET and waiting for a wrap
510 * around to find out, that a tick has elapsed. I have a box, where the PIT
511 * readout is broken, so it never gets out of the wait loop again. This was
512 * also reported by others.
514 * Monitoring the jiffies value is inaccurate and the clockevents
515 * infrastructure allows us to do a simple substitution of the interrupt
518 * The calibration routine also uses the pm_timer when possible, as the PIT
519 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
520 * back to normal later in the boot process).
523 #define LAPIC_CAL_LOOPS (HZ/10)
525 static __initdata int lapic_cal_loops = -1;
526 static __initdata long lapic_cal_t1, lapic_cal_t2;
527 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
528 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
529 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
532 * Temporary interrupt handler.
534 static void __init lapic_cal_handler(struct clock_event_device *dev)
536 unsigned long long tsc = 0;
537 long tapic = apic_read(APIC_TMCCT);
538 unsigned long pm = acpi_pm_read_early();
543 switch (lapic_cal_loops++) {
545 lapic_cal_t1 = tapic;
546 lapic_cal_tsc1 = tsc;
548 lapic_cal_j1 = jiffies;
551 case LAPIC_CAL_LOOPS:
552 lapic_cal_t2 = tapic;
553 lapic_cal_tsc2 = tsc;
554 if (pm < lapic_cal_pm1)
555 pm += ACPI_PM_OVRRUN;
557 lapic_cal_j2 = jiffies;
563 calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
565 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
566 const long pm_thresh = pm_100ms / 100;
570 #ifndef CONFIG_X86_PM_TIMER
574 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
576 /* Check, if the PM timer is available */
580 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
582 if (deltapm > (pm_100ms - pm_thresh) &&
583 deltapm < (pm_100ms + pm_thresh)) {
584 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
588 res = (((u64)deltapm) * mult) >> 22;
589 do_div(res, 1000000);
590 pr_warning("APIC calibration not consistent "
591 "with PM-Timer: %ldms instead of 100ms\n",(long)res);
593 /* Correct the lapic counter value */
594 res = (((u64)(*delta)) * pm_100ms);
595 do_div(res, deltapm);
596 pr_info("APIC delta adjusted to PM-Timer: "
597 "%lu (%ld)\n", (unsigned long)res, *delta);
600 /* Correct the tsc counter value */
602 res = (((u64)(*deltatsc)) * pm_100ms);
603 do_div(res, deltapm);
604 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
605 "PM-Timer: %lu (%ld) \n",
606 (unsigned long)res, *deltatsc);
607 *deltatsc = (long)res;
613 static int __init calibrate_APIC_clock(void)
615 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
616 void (*real_handler)(struct clock_event_device *dev);
617 unsigned long deltaj;
618 long delta, deltatsc;
619 int pm_referenced = 0;
623 /* Replace the global interrupt handler */
624 real_handler = global_clock_event->event_handler;
625 global_clock_event->event_handler = lapic_cal_handler;
628 * Setup the APIC counter to maximum. There is no way the lapic
629 * can underflow in the 100ms detection time frame
631 __setup_APIC_LVTT(0xffffffff, 0, 0);
633 /* Let the interrupts run */
636 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
641 /* Restore the real event handler */
642 global_clock_event->event_handler = real_handler;
644 /* Build delta t1-t2 as apic timer counts down */
645 delta = lapic_cal_t1 - lapic_cal_t2;
646 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
648 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
650 /* we trust the PM based calibration if possible */
651 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
654 /* Calculate the scaled math multiplication factor */
655 lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
656 lapic_clockevent.shift);
657 lapic_clockevent.max_delta_ns =
658 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
659 lapic_clockevent.min_delta_ns =
660 clockevent_delta2ns(0xF, &lapic_clockevent);
662 calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
664 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
665 apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
666 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
670 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
672 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
673 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
676 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
678 calibration_result / (1000000 / HZ),
679 calibration_result % (1000000 / HZ));
682 * Do a sanity check on the APIC calibration result
684 if (calibration_result < (1000000 / HZ)) {
686 pr_warning("APIC frequency too slow, disabling apic timer\n");
690 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
693 * PM timer calibration failed or not turned on
694 * so lets try APIC timer based calibration
696 if (!pm_referenced) {
697 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
700 * Setup the apic timer manually
702 levt->event_handler = lapic_cal_handler;
703 lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
704 lapic_cal_loops = -1;
706 /* Let the interrupts run */
709 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
712 /* Stop the lapic timer */
713 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
716 deltaj = lapic_cal_j2 - lapic_cal_j1;
717 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
719 /* Check, if the jiffies result is consistent */
720 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
721 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
723 levt->features |= CLOCK_EVT_FEAT_DUMMY;
727 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
728 pr_warning("APIC timer disabled due to verification failure\n");
736 * Setup the boot APIC
738 * Calibrate and verify the result.
740 void __init setup_boot_APIC_clock(void)
743 * The local apic timer can be disabled via the kernel
744 * commandline or from the CPU detection code. Register the lapic
745 * timer as a dummy clock event source on SMP systems, so the
746 * broadcast mechanism is used. On UP systems simply ignore it.
748 if (disable_apic_timer) {
749 pr_info("Disabling APIC timer\n");
750 /* No broadcast on UP ! */
751 if (num_possible_cpus() > 1) {
752 lapic_clockevent.mult = 1;
758 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
759 "calibrating APIC timer ...\n");
761 if (calibrate_APIC_clock()) {
762 /* No broadcast on UP ! */
763 if (num_possible_cpus() > 1)
769 * If nmi_watchdog is set to IO_APIC, we need the
770 * PIT/HPET going. Otherwise register lapic as a dummy
773 if (nmi_watchdog != NMI_IO_APIC)
774 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
776 pr_warning("APIC timer registered as dummy,"
777 " due to nmi_watchdog=%d!\n", nmi_watchdog);
779 /* Setup the lapic or request the broadcast */
783 void __cpuinit setup_secondary_APIC_clock(void)
789 * The guts of the apic timer interrupt
791 static void local_apic_timer_interrupt(void)
793 int cpu = smp_processor_id();
794 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
797 * Normally we should not be here till LAPIC has been initialized but
798 * in some cases like kdump, its possible that there is a pending LAPIC
799 * timer interrupt from previous kernel's context and is delivered in
800 * new kernel the moment interrupts are enabled.
802 * Interrupts are enabled early and LAPIC is setup much later, hence
803 * its possible that when we get here evt->event_handler is NULL.
804 * Check for event_handler being NULL and discard the interrupt as
807 if (!evt->event_handler) {
808 pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
810 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
815 * the NMI deadlock-detector uses this.
817 inc_irq_stat(apic_timer_irqs);
819 evt->event_handler(evt);
823 * Local APIC timer interrupt. This is the most natural way for doing
824 * local interrupts, but local timer interrupts can be emulated by
825 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
827 * [ if a single-CPU system runs an SMP kernel then we call the local
828 * interrupt as well. Thus we cannot inline the local irq ... ]
830 void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
832 struct pt_regs *old_regs = set_irq_regs(regs);
835 * NOTE! We'd better ACK the irq immediately,
836 * because timer handling can be slow.
840 * update_process_times() expects us to have done irq_enter().
841 * Besides, if we don't timer interrupts ignore the global
842 * interrupt lock, which is the WrongThing (tm) to do.
846 local_apic_timer_interrupt();
849 set_irq_regs(old_regs);
852 int setup_profiling_timer(unsigned int multiplier)
858 * Local APIC start and shutdown
862 * clear_local_APIC - shutdown the local APIC
864 * This is called, when a CPU is disabled and before rebooting, so the state of
865 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
866 * leftovers during boot.
868 void clear_local_APIC(void)
873 /* APIC hasn't been mapped yet */
874 if (!x2apic_mode && !apic_phys)
877 maxlvt = lapic_get_maxlvt();
879 * Masking an LVT entry can trigger a local APIC error
880 * if the vector is zero. Mask LVTERR first to prevent this.
883 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
884 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
887 * Careful: we have to set masks only first to deassert
888 * any level-triggered sources.
890 v = apic_read(APIC_LVTT);
891 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
892 v = apic_read(APIC_LVT0);
893 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
894 v = apic_read(APIC_LVT1);
895 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
897 v = apic_read(APIC_LVTPC);
898 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
901 /* lets not touch this if we didn't frob it */
902 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
904 v = apic_read(APIC_LVTTHMR);
905 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
908 #ifdef CONFIG_X86_MCE_INTEL
910 v = apic_read(APIC_LVTCMCI);
911 if (!(v & APIC_LVT_MASKED))
912 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
917 * Clean APIC state for other OSs:
919 apic_write(APIC_LVTT, APIC_LVT_MASKED);
920 apic_write(APIC_LVT0, APIC_LVT_MASKED);
921 apic_write(APIC_LVT1, APIC_LVT_MASKED);
923 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
925 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
927 /* Integrated APIC (!82489DX) ? */
928 if (lapic_is_integrated()) {
930 /* Clear ESR due to Pentium errata 3AP and 11AP */
931 apic_write(APIC_ESR, 0);
937 * disable_local_APIC - clear and disable the local APIC
939 void disable_local_APIC(void)
943 /* APIC hasn't been mapped yet */
950 * Disable APIC (implies clearing of registers
953 value = apic_read(APIC_SPIV);
954 value &= ~APIC_SPIV_APIC_ENABLED;
955 apic_write(APIC_SPIV, value);
959 * When LAPIC was disabled by the BIOS and enabled by the kernel,
960 * restore the disabled state.
962 if (enabled_via_apicbase) {
965 rdmsr(MSR_IA32_APICBASE, l, h);
966 l &= ~MSR_IA32_APICBASE_ENABLE;
967 wrmsr(MSR_IA32_APICBASE, l, h);
973 * If Linux enabled the LAPIC against the BIOS default disable it down before
974 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
975 * not power-off. Additionally clear all LVT entries before disable_local_APIC
976 * for the case where Linux didn't enable the LAPIC.
978 void lapic_shutdown(void)
985 local_irq_save(flags);
988 if (!enabled_via_apicbase)
992 disable_local_APIC();
995 local_irq_restore(flags);
999 * This is to verify that we're looking at a real local APIC.
1000 * Check these against your board if the CPUs aren't getting
1001 * started for no apparent reason.
1003 int __init verify_local_APIC(void)
1005 unsigned int reg0, reg1;
1008 * The version register is read-only in a real APIC.
1010 reg0 = apic_read(APIC_LVR);
1011 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
1012 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
1013 reg1 = apic_read(APIC_LVR);
1014 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
1017 * The two version reads above should print the same
1018 * numbers. If the second one is different, then we
1019 * poke at a non-APIC.
1025 * Check if the version looks reasonably.
1027 reg1 = GET_APIC_VERSION(reg0);
1028 if (reg1 == 0x00 || reg1 == 0xff)
1030 reg1 = lapic_get_maxlvt();
1031 if (reg1 < 0x02 || reg1 == 0xff)
1035 * The ID register is read/write in a real APIC.
1037 reg0 = apic_read(APIC_ID);
1038 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
1039 apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
1040 reg1 = apic_read(APIC_ID);
1041 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
1042 apic_write(APIC_ID, reg0);
1043 if (reg1 != (reg0 ^ apic->apic_id_mask))
1047 * The next two are just to see if we have sane values.
1048 * They're only really relevant if we're in Virtual Wire
1049 * compatibility mode, but most boxes are anymore.
1051 reg0 = apic_read(APIC_LVT0);
1052 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
1053 reg1 = apic_read(APIC_LVT1);
1054 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
1060 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1062 void __init sync_Arb_IDs(void)
1065 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1068 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1074 apic_wait_icr_idle();
1076 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1077 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1078 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1082 * An initial setup of the virtual wire mode.
1084 void __init init_bsp_APIC(void)
1089 * Don't do the setup now if we have a SMP BIOS as the
1090 * through-I/O-APIC virtual wire mode might be active.
1092 if (smp_found_config || !cpu_has_apic)
1096 * Do not trust the local APIC being empty at bootup.
1103 value = apic_read(APIC_SPIV);
1104 value &= ~APIC_VECTOR_MASK;
1105 value |= APIC_SPIV_APIC_ENABLED;
1107 #ifdef CONFIG_X86_32
1108 /* This bit is reserved on P4/Xeon and should be cleared */
1109 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1110 (boot_cpu_data.x86 == 15))
1111 value &= ~APIC_SPIV_FOCUS_DISABLED;
1114 value |= APIC_SPIV_FOCUS_DISABLED;
1115 value |= SPURIOUS_APIC_VECTOR;
1116 apic_write(APIC_SPIV, value);
1119 * Set up the virtual wire mode.
1121 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1122 value = APIC_DM_NMI;
1123 if (!lapic_is_integrated()) /* 82489DX */
1124 value |= APIC_LVT_LEVEL_TRIGGER;
1125 apic_write(APIC_LVT1, value);
1128 static void __cpuinit lapic_setup_esr(void)
1130 unsigned int oldvalue, value, maxlvt;
1132 if (!lapic_is_integrated()) {
1133 pr_info("No ESR for 82489DX.\n");
1137 if (apic->disable_esr) {
1139 * Something untraceable is creating bad interrupts on
1140 * secondary quads ... for the moment, just leave the
1141 * ESR disabled - we can't do anything useful with the
1142 * errors anyway - mbligh
1144 pr_info("Leaving ESR disabled.\n");
1148 maxlvt = lapic_get_maxlvt();
1149 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1150 apic_write(APIC_ESR, 0);
1151 oldvalue = apic_read(APIC_ESR);
1153 /* enables sending errors */
1154 value = ERROR_APIC_VECTOR;
1155 apic_write(APIC_LVTERR, value);
1158 * spec says clear errors after enabling vector.
1161 apic_write(APIC_ESR, 0);
1162 value = apic_read(APIC_ESR);
1163 if (value != oldvalue)
1164 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1165 "vector: 0x%08x after: 0x%08x\n",
1171 * setup_local_APIC - setup the local APIC
1173 void __cpuinit setup_local_APIC(void)
1179 arch_disable_smp_support();
1183 #ifdef CONFIG_X86_32
1184 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1185 if (lapic_is_integrated() && apic->disable_esr) {
1186 apic_write(APIC_ESR, 0);
1187 apic_write(APIC_ESR, 0);
1188 apic_write(APIC_ESR, 0);
1189 apic_write(APIC_ESR, 0);
1192 perf_counters_lapic_init();
1197 * Double-check whether this APIC is really registered.
1198 * This is meaningless in clustered apic mode, so we skip it.
1200 if (!apic->apic_id_registered())
1204 * Intel recommends to set DFR, LDR and TPR before enabling
1205 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1206 * document number 292116). So here it goes...
1208 apic->init_apic_ldr();
1211 * Set Task Priority to 'accept all'. We never change this
1214 value = apic_read(APIC_TASKPRI);
1215 value &= ~APIC_TPRI_MASK;
1216 apic_write(APIC_TASKPRI, value);
1219 * After a crash, we no longer service the interrupts and a pending
1220 * interrupt from previous kernel might still have ISR bit set.
1222 * Most probably by now CPU has serviced that pending interrupt and
1223 * it might not have done the ack_APIC_irq() because it thought,
1224 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1225 * does not clear the ISR bit and cpu thinks it has already serivced
1226 * the interrupt. Hence a vector might get locked. It was noticed
1227 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1229 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1230 value = apic_read(APIC_ISR + i*0x10);
1231 for (j = 31; j >= 0; j--) {
1238 * Now that we are all set up, enable the APIC
1240 value = apic_read(APIC_SPIV);
1241 value &= ~APIC_VECTOR_MASK;
1245 value |= APIC_SPIV_APIC_ENABLED;
1247 #ifdef CONFIG_X86_32
1249 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1250 * certain networking cards. If high frequency interrupts are
1251 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1252 * entry is masked/unmasked at a high rate as well then sooner or
1253 * later IOAPIC line gets 'stuck', no more interrupts are received
1254 * from the device. If focus CPU is disabled then the hang goes
1257 * [ This bug can be reproduced easily with a level-triggered
1258 * PCI Ne2000 networking cards and PII/PIII processors, dual
1262 * Actually disabling the focus CPU check just makes the hang less
1263 * frequent as it makes the interrupt distributon model be more
1264 * like LRU than MRU (the short-term load is more even across CPUs).
1265 * See also the comment in end_level_ioapic_irq(). --macro
1269 * - enable focus processor (bit==0)
1270 * - 64bit mode always use processor focus
1271 * so no need to set it
1273 value &= ~APIC_SPIV_FOCUS_DISABLED;
1277 * Set spurious IRQ vector
1279 value |= SPURIOUS_APIC_VECTOR;
1280 apic_write(APIC_SPIV, value);
1283 * Set up LVT0, LVT1:
1285 * set up through-local-APIC on the BP's LINT0. This is not
1286 * strictly necessary in pure symmetric-IO mode, but sometimes
1287 * we delegate interrupts to the 8259A.
1290 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1292 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1293 if (!smp_processor_id() && (pic_mode || !value)) {
1294 value = APIC_DM_EXTINT;
1295 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1296 smp_processor_id());
1298 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1299 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1300 smp_processor_id());
1302 apic_write(APIC_LVT0, value);
1305 * only the BP should see the LINT1 NMI signal, obviously.
1307 if (!smp_processor_id())
1308 value = APIC_DM_NMI;
1310 value = APIC_DM_NMI | APIC_LVT_MASKED;
1311 if (!lapic_is_integrated()) /* 82489DX */
1312 value |= APIC_LVT_LEVEL_TRIGGER;
1313 apic_write(APIC_LVT1, value);
1317 #ifdef CONFIG_X86_MCE_INTEL
1318 /* Recheck CMCI information after local APIC is up on CPU #0 */
1319 if (smp_processor_id() == 0)
1324 void __cpuinit end_local_APIC_setup(void)
1328 #ifdef CONFIG_X86_32
1331 /* Disable the local apic timer */
1332 value = apic_read(APIC_LVTT);
1333 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1334 apic_write(APIC_LVTT, value);
1338 setup_apic_nmi_watchdog(NULL);
1342 #ifdef CONFIG_X86_X2APIC
1343 void check_x2apic(void)
1345 if (x2apic_enabled()) {
1346 pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
1347 x2apic_preenabled = x2apic_mode = 1;
1351 void enable_x2apic(void)
1358 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1359 if (!(msr & X2APIC_ENABLE)) {
1360 pr_info("Enabling x2apic\n");
1361 wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1364 #endif /* CONFIG_X86_X2APIC */
1366 void __init enable_IR_x2apic(void)
1368 #ifdef CONFIG_INTR_REMAP
1370 unsigned long flags;
1371 struct IO_APIC_route_entry **ioapic_entries = NULL;
1373 ret = dmar_table_init();
1375 pr_debug("dmar_table_init() failed with %d:\n", ret);
1379 if (!intr_remapping_supported()) {
1380 pr_debug("intr-remapping not supported\n");
1385 if (!x2apic_preenabled && skip_ioapic_setup) {
1386 pr_info("Skipped enabling intr-remap because of skipping "
1391 ioapic_entries = alloc_ioapic_entries();
1392 if (!ioapic_entries) {
1393 pr_info("Allocate ioapic_entries failed: %d\n", ret);
1397 ret = save_IO_APIC_setup(ioapic_entries);
1399 pr_info("Saving IO-APIC state failed: %d\n", ret);
1403 local_irq_save(flags);
1404 mask_IO_APIC_setup(ioapic_entries);
1407 ret = enable_intr_remapping(x2apic_supported());
1411 pr_info("Enabled Interrupt-remapping\n");
1413 if (x2apic_supported() && !x2apic_mode) {
1416 pr_info("Enabled x2apic\n");
1422 * IR enabling failed
1424 restore_IO_APIC_setup(ioapic_entries);
1427 local_irq_restore(flags);
1431 free_ioapic_entries(ioapic_entries);
1437 if (x2apic_preenabled)
1438 panic("x2apic enabled by bios. But IR enabling failed");
1439 else if (cpu_has_x2apic)
1440 pr_info("Not enabling x2apic,Intr-remapping\n");
1442 if (!cpu_has_x2apic)
1445 if (x2apic_preenabled)
1446 panic("x2apic enabled prior OS handover,"
1447 " enable CONFIG_X86_X2APIC, CONFIG_INTR_REMAP");
1454 #ifdef CONFIG_X86_64
1456 * Detect and enable local APICs on non-SMP boards.
1457 * Original code written by Keir Fraser.
1458 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1459 * not correctly set up (usually the APIC timer won't work etc.)
1461 static int __init detect_init_APIC(void)
1463 if (!cpu_has_apic) {
1464 pr_info("No local APIC present\n");
1468 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1473 * Detect and initialize APIC
1475 static int __init detect_init_APIC(void)
1479 /* Disabled by kernel option? */
1483 switch (boot_cpu_data.x86_vendor) {
1484 case X86_VENDOR_AMD:
1485 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1486 (boot_cpu_data.x86 >= 15))
1489 case X86_VENDOR_INTEL:
1490 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1491 (boot_cpu_data.x86 == 5 && cpu_has_apic))
1498 if (!cpu_has_apic) {
1500 * Over-ride BIOS and try to enable the local APIC only if
1501 * "lapic" specified.
1503 if (!force_enable_local_apic) {
1504 pr_info("Local APIC disabled by BIOS -- "
1505 "you can enable it with \"lapic\"\n");
1509 * Some BIOSes disable the local APIC in the APIC_BASE
1510 * MSR. This can only be done in software for Intel P6 or later
1511 * and AMD K7 (Model > 1) or later.
1513 rdmsr(MSR_IA32_APICBASE, l, h);
1514 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1515 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1516 l &= ~MSR_IA32_APICBASE_BASE;
1517 l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
1518 wrmsr(MSR_IA32_APICBASE, l, h);
1519 enabled_via_apicbase = 1;
1523 * The APIC feature bit should now be enabled
1526 features = cpuid_edx(1);
1527 if (!(features & (1 << X86_FEATURE_APIC))) {
1528 pr_warning("Could not enable APIC!\n");
1531 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1532 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1534 /* The BIOS may have set up the APIC at some other address */
1535 rdmsr(MSR_IA32_APICBASE, l, h);
1536 if (l & MSR_IA32_APICBASE_ENABLE)
1537 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1539 pr_info("Found and enabled local APIC!\n");
1546 pr_info("No local APIC present or hardware disabled\n");
1551 #ifdef CONFIG_X86_64
1552 void __init early_init_lapic_mapping(void)
1554 unsigned long phys_addr;
1557 * If no local APIC can be found then go out
1558 * : it means there is no mpatable and MADT
1560 if (!smp_found_config)
1563 phys_addr = mp_lapic_addr;
1565 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1566 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1567 APIC_BASE, phys_addr);
1570 * Fetch the APIC ID of the BSP in case we have a
1571 * default configuration (or the MP table is broken).
1573 boot_cpu_physical_apicid = read_apic_id();
1578 * init_apic_mappings - initialize APIC mappings
1580 void __init init_apic_mappings(void)
1582 unsigned int new_apicid;
1585 boot_cpu_physical_apicid = read_apic_id();
1589 /* If no local APIC can be found return early */
1590 if (!smp_found_config && detect_init_APIC()) {
1591 /* lets NOP'ify apic operations */
1592 pr_info("APIC: disable apic facility\n");
1595 apic_phys = mp_lapic_addr;
1598 * acpi lapic path already maps that address in
1599 * acpi_register_lapic_address()
1602 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1604 apic_printk(APIC_VERBOSE, "mapped APIC to %08lx (%08lx)\n",
1605 APIC_BASE, apic_phys);
1609 * Fetch the APIC ID of the BSP in case we have a
1610 * default configuration (or the MP table is broken).
1612 new_apicid = read_apic_id();
1613 if (boot_cpu_physical_apicid != new_apicid) {
1614 boot_cpu_physical_apicid = new_apicid;
1616 * yeah -- we lie about apic_version
1617 * in case if apic was disabled via boot option
1618 * but it's not a problem for SMP compiled kernel
1619 * since smp_sanity_check is prepared for such a case
1620 * and disable smp mode
1622 apic_version[new_apicid] =
1623 GET_APIC_VERSION(apic_read(APIC_LVR));
1628 * This initializes the IO-APIC and APIC hardware if this is
1631 int apic_version[MAX_APICS];
1633 int __init APIC_init_uniprocessor(void)
1636 pr_info("Apic disabled\n");
1639 #ifdef CONFIG_X86_64
1640 if (!cpu_has_apic) {
1642 pr_info("Apic disabled by BIOS\n");
1646 if (!smp_found_config && !cpu_has_apic)
1650 * Complain if the BIOS pretends there is one.
1652 if (!cpu_has_apic &&
1653 APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1654 pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
1655 boot_cpu_physical_apicid);
1656 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1662 #ifdef CONFIG_X86_64
1663 default_setup_apic_routing();
1666 verify_local_APIC();
1669 #ifdef CONFIG_X86_64
1670 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1673 * Hack: In case of kdump, after a crash, kernel might be booting
1674 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1675 * might be zero if read from MP tables. Get it from LAPIC.
1677 # ifdef CONFIG_CRASH_DUMP
1678 boot_cpu_physical_apicid = read_apic_id();
1681 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1684 #ifdef CONFIG_X86_IO_APIC
1686 * Now enable IO-APICs, actually call clear_IO_APIC
1687 * We need clear_IO_APIC before enabling error vector
1689 if (!skip_ioapic_setup && nr_ioapics)
1693 end_local_APIC_setup();
1695 #ifdef CONFIG_X86_IO_APIC
1696 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1700 localise_nmi_watchdog();
1703 localise_nmi_watchdog();
1707 #ifdef CONFIG_X86_64
1708 check_nmi_watchdog();
1715 * Local APIC interrupts
1719 * This interrupt should _never_ happen with our APIC/SMP architecture
1721 void smp_spurious_interrupt(struct pt_regs *regs)
1728 * Check if this really is a spurious interrupt and ACK it
1729 * if it is a vectored one. Just in case...
1730 * Spurious interrupts should not be ACKed.
1732 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1733 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1736 inc_irq_stat(irq_spurious_count);
1738 /* see sw-dev-man vol 3, chapter 7.4.13.5 */
1739 pr_info("spurious APIC interrupt on CPU#%d, "
1740 "should never happen.\n", smp_processor_id());
1745 * This interrupt should never happen with our APIC/SMP architecture
1747 void smp_error_interrupt(struct pt_regs *regs)
1753 /* First tickle the hardware, only then report what went on. -- REW */
1754 v = apic_read(APIC_ESR);
1755 apic_write(APIC_ESR, 0);
1756 v1 = apic_read(APIC_ESR);
1758 atomic_inc(&irq_err_count);
1761 * Here is what the APIC error bits mean:
1763 * 1: Receive CS error
1764 * 2: Send accept error
1765 * 3: Receive accept error
1767 * 5: Send illegal vector
1768 * 6: Received illegal vector
1769 * 7: Illegal register address
1771 pr_debug("APIC error on CPU%d: %02x(%02x)\n",
1772 smp_processor_id(), v , v1);
1777 * connect_bsp_APIC - attach the APIC to the interrupt system
1779 void __init connect_bsp_APIC(void)
1781 #ifdef CONFIG_X86_32
1784 * Do not trust the local APIC being empty at bootup.
1788 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
1789 * local APIC to INT and NMI lines.
1791 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1792 "enabling APIC mode.\n");
1796 if (apic->enable_apic_mode)
1797 apic->enable_apic_mode();
1801 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1802 * @virt_wire_setup: indicates, whether virtual wire mode is selected
1804 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1807 void disconnect_bsp_APIC(int virt_wire_setup)
1811 #ifdef CONFIG_X86_32
1814 * Put the board back into PIC mode (has an effect only on
1815 * certain older boards). Note that APIC interrupts, including
1816 * IPIs, won't work beyond this point! The only exception are
1819 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1820 "entering PIC mode.\n");
1826 /* Go back to Virtual Wire compatibility mode */
1828 /* For the spurious interrupt use vector F, and enable it */
1829 value = apic_read(APIC_SPIV);
1830 value &= ~APIC_VECTOR_MASK;
1831 value |= APIC_SPIV_APIC_ENABLED;
1833 apic_write(APIC_SPIV, value);
1835 if (!virt_wire_setup) {
1837 * For LVT0 make it edge triggered, active high,
1838 * external and enabled
1840 value = apic_read(APIC_LVT0);
1841 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1842 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1843 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1844 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1845 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1846 apic_write(APIC_LVT0, value);
1849 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1853 * For LVT1 make it edge triggered, active high,
1856 value = apic_read(APIC_LVT1);
1857 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1858 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1859 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1860 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1861 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1862 apic_write(APIC_LVT1, value);
1865 void __cpuinit generic_processor_info(int apicid, int version)
1872 if (version == 0x0) {
1873 pr_warning("BIOS bug, APIC version is 0 for CPU#%d! "
1874 "fixing up to 0x10. (tell your hw vendor)\n",
1878 apic_version[apicid] = version;
1880 if (num_processors >= nr_cpu_ids) {
1881 int max = nr_cpu_ids;
1882 int thiscpu = max + disabled_cpus;
1885 "ACPI: NR_CPUS/possible_cpus limit of %i reached."
1886 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
1893 cpu = cpumask_next_zero(-1, cpu_present_mask);
1895 if (version != apic_version[boot_cpu_physical_apicid])
1897 "ACPI: apic version mismatch, bootcpu: %x cpu %d: %x\n",
1898 apic_version[boot_cpu_physical_apicid], cpu, version);
1900 physid_set(apicid, phys_cpu_present_map);
1901 if (apicid == boot_cpu_physical_apicid) {
1903 * x86_bios_cpu_apicid is required to have processors listed
1904 * in same order as logical cpu numbers. Hence the first
1905 * entry is BSP, and so on.
1909 if (apicid > max_physical_apicid)
1910 max_physical_apicid = apicid;
1912 #ifdef CONFIG_X86_32
1914 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
1915 * but we need to work other dependencies like SMP_SUSPEND etc
1916 * before this can be done without some confusion.
1917 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
1918 * - Ashok Raj <ashok.raj@intel.com>
1920 if (max_physical_apicid >= 8) {
1921 switch (boot_cpu_data.x86_vendor) {
1922 case X86_VENDOR_INTEL:
1923 if (!APIC_XAPIC(version)) {
1927 /* If P4 and above fall through */
1928 case X86_VENDOR_AMD:
1934 #if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
1935 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1936 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1939 set_cpu_possible(cpu, true);
1940 set_cpu_present(cpu, true);
1943 int hard_smp_processor_id(void)
1945 return read_apic_id();
1948 void default_init_apic_ldr(void)
1952 apic_write(APIC_DFR, APIC_DFR_VALUE);
1953 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
1954 val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
1955 apic_write(APIC_LDR, val);
1958 #ifdef CONFIG_X86_32
1959 int default_apicid_to_node(int logical_apicid)
1962 return apicid_2_node[hard_smp_processor_id()];
1976 * 'active' is true if the local APIC was enabled by us and
1977 * not the BIOS; this signifies that we are also responsible
1978 * for disabling it before entering apm/acpi suspend
1981 /* r/w apic fields */
1982 unsigned int apic_id;
1983 unsigned int apic_taskpri;
1984 unsigned int apic_ldr;
1985 unsigned int apic_dfr;
1986 unsigned int apic_spiv;
1987 unsigned int apic_lvtt;
1988 unsigned int apic_lvtpc;
1989 unsigned int apic_lvt0;
1990 unsigned int apic_lvt1;
1991 unsigned int apic_lvterr;
1992 unsigned int apic_tmict;
1993 unsigned int apic_tdcr;
1994 unsigned int apic_thmr;
1997 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1999 unsigned long flags;
2002 if (!apic_pm_state.active)
2005 maxlvt = lapic_get_maxlvt();
2007 apic_pm_state.apic_id = apic_read(APIC_ID);
2008 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2009 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2010 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2011 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2012 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2014 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2015 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2016 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2017 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2018 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2019 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2020 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2022 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2025 local_irq_save(flags);
2026 disable_local_APIC();
2028 if (intr_remapping_enabled)
2029 disable_intr_remapping();
2031 local_irq_restore(flags);
2035 static int lapic_resume(struct sys_device *dev)
2038 unsigned long flags;
2041 struct IO_APIC_route_entry **ioapic_entries = NULL;
2043 if (!apic_pm_state.active)
2046 local_irq_save(flags);
2047 if (intr_remapping_enabled) {
2048 ioapic_entries = alloc_ioapic_entries();
2049 if (!ioapic_entries) {
2050 WARN(1, "Alloc ioapic_entries in lapic resume failed.");
2055 ret = save_IO_APIC_setup(ioapic_entries);
2057 WARN(1, "Saving IO-APIC state failed: %d\n", ret);
2058 free_ioapic_entries(ioapic_entries);
2062 mask_IO_APIC_setup(ioapic_entries);
2070 * Make sure the APICBASE points to the right address
2072 * FIXME! This will be wrong if we ever support suspend on
2073 * SMP! We'll need to do this as part of the CPU restore!
2075 rdmsr(MSR_IA32_APICBASE, l, h);
2076 l &= ~MSR_IA32_APICBASE_BASE;
2077 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2078 wrmsr(MSR_IA32_APICBASE, l, h);
2081 maxlvt = lapic_get_maxlvt();
2082 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2083 apic_write(APIC_ID, apic_pm_state.apic_id);
2084 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2085 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2086 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2087 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2088 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2089 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2090 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2092 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2095 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2096 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2097 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2098 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2099 apic_write(APIC_ESR, 0);
2100 apic_read(APIC_ESR);
2101 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2102 apic_write(APIC_ESR, 0);
2103 apic_read(APIC_ESR);
2105 if (intr_remapping_enabled) {
2106 reenable_intr_remapping(x2apic_mode);
2108 restore_IO_APIC_setup(ioapic_entries);
2109 free_ioapic_entries(ioapic_entries);
2112 local_irq_restore(flags);
2118 * This device has no shutdown method - fully functioning local APICs
2119 * are needed on every CPU up until machine_halt/restart/poweroff.
2122 static struct sysdev_class lapic_sysclass = {
2124 .resume = lapic_resume,
2125 .suspend = lapic_suspend,
2128 static struct sys_device device_lapic = {
2130 .cls = &lapic_sysclass,
2133 static void __cpuinit apic_pm_activate(void)
2135 apic_pm_state.active = 1;
2138 static int __init init_lapic_sysfs(void)
2144 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2146 error = sysdev_class_register(&lapic_sysclass);
2148 error = sysdev_register(&device_lapic);
2152 /* local apic needs to resume before other devices access its registers. */
2153 core_initcall(init_lapic_sysfs);
2155 #else /* CONFIG_PM */
2157 static void apic_pm_activate(void) { }
2159 #endif /* CONFIG_PM */
2161 #ifdef CONFIG_X86_64
2163 static int __cpuinit apic_cluster_num(void)
2165 int i, clusters, zeros;
2167 u16 *bios_cpu_apicid;
2168 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2170 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2171 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2173 for (i = 0; i < nr_cpu_ids; i++) {
2174 /* are we being called early in kernel startup? */
2175 if (bios_cpu_apicid) {
2176 id = bios_cpu_apicid[i];
2177 } else if (i < nr_cpu_ids) {
2179 id = per_cpu(x86_bios_cpu_apicid, i);
2185 if (id != BAD_APICID)
2186 __set_bit(APIC_CLUSTERID(id), clustermap);
2189 /* Problem: Partially populated chassis may not have CPUs in some of
2190 * the APIC clusters they have been allocated. Only present CPUs have
2191 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2192 * Since clusters are allocated sequentially, count zeros only if
2193 * they are bounded by ones.
2197 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2198 if (test_bit(i, clustermap)) {
2199 clusters += 1 + zeros;
2208 static int __cpuinitdata multi_checked;
2209 static int __cpuinitdata multi;
2211 static int __cpuinit set_multi(const struct dmi_system_id *d)
2215 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2220 static const __cpuinitconst struct dmi_system_id multi_dmi_table[] = {
2222 .callback = set_multi,
2223 .ident = "IBM System Summit2",
2225 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2226 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2232 static void __cpuinit dmi_check_multi(void)
2237 dmi_check_system(multi_dmi_table);
2242 * apic_is_clustered_box() -- Check if we can expect good TSC
2244 * Thus far, the major user of this is IBM's Summit2 series:
2245 * Clustered boxes may have unsynced TSC problems if they are
2247 * Use DMI to check them
2249 __cpuinit int apic_is_clustered_box(void)
2259 * ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2260 * not guaranteed to be synced between boards
2262 if (apic_cluster_num() > 1)
2270 * APIC command line parameters
2272 static int __init setup_disableapic(char *arg)
2275 setup_clear_cpu_cap(X86_FEATURE_APIC);
2278 early_param("disableapic", setup_disableapic);
2280 /* same as disableapic, for compatibility */
2281 static int __init setup_nolapic(char *arg)
2283 return setup_disableapic(arg);
2285 early_param("nolapic", setup_nolapic);
2287 static int __init parse_lapic_timer_c2_ok(char *arg)
2289 local_apic_timer_c2_ok = 1;
2292 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2294 static int __init parse_disable_apic_timer(char *arg)
2296 disable_apic_timer = 1;
2299 early_param("noapictimer", parse_disable_apic_timer);
2301 static int __init parse_nolapic_timer(char *arg)
2303 disable_apic_timer = 1;
2306 early_param("nolapic_timer", parse_nolapic_timer);
2308 static int __init apic_set_verbosity(char *arg)
2311 #ifdef CONFIG_X86_64
2312 skip_ioapic_setup = 0;
2318 if (strcmp("debug", arg) == 0)
2319 apic_verbosity = APIC_DEBUG;
2320 else if (strcmp("verbose", arg) == 0)
2321 apic_verbosity = APIC_VERBOSE;
2323 pr_warning("APIC Verbosity level %s not recognised"
2324 " use apic=verbose or apic=debug\n", arg);
2330 early_param("apic", apic_set_verbosity);
2332 static int __init lapic_insert_resource(void)
2337 /* Put local APIC into the resource map. */
2338 lapic_resource.start = apic_phys;
2339 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2340 insert_resource(&iomem_resource, &lapic_resource);
2346 * need call insert after e820_reserve_resources()
2347 * that is using request_resource
2349 late_initcall(lapic_insert_resource);