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_event.h>
18 #include <linux/kernel_stat.h>
19 #include <linux/mc146818rtc.h>
20 #include <linux/acpi_pmtmr.h>
21 #include <linux/clockchips.h>
22 #include <linux/interrupt.h>
23 #include <linux/memblock.h>
24 #include <linux/ftrace.h>
25 #include <linux/ioport.h>
26 #include <linux/export.h>
27 #include <linux/syscore_ops.h>
28 #include <linux/delay.h>
29 #include <linux/timex.h>
30 #include <linux/i8253.h>
31 #include <linux/dmar.h>
32 #include <linux/init.h>
33 #include <linux/cpu.h>
34 #include <linux/dmi.h>
35 #include <linux/smp.h>
38 #include <asm/trace/irq_vectors.h>
39 #include <asm/irq_remapping.h>
40 #include <asm/perf_event.h>
41 #include <asm/x86_init.h>
42 #include <asm/pgalloc.h>
43 #include <linux/atomic.h>
44 #include <asm/mpspec.h>
45 #include <asm/i8259.h>
46 #include <asm/proto.h>
47 #include <asm/traps.h>
49 #include <asm/io_apic.h>
57 #include <asm/hypervisor.h>
58 #include <asm/cpu_device_id.h>
59 #include <asm/intel-family.h>
60 #include <asm/irq_regs.h>
62 unsigned int num_processors;
64 unsigned disabled_cpus;
66 /* Processor that is doing the boot up */
67 unsigned int boot_cpu_physical_apicid = -1U;
68 EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
70 u8 boot_cpu_apic_version;
73 * The highest APIC ID seen during enumeration.
75 static unsigned int max_physical_apicid;
78 * Bitmask of physically existing CPUs:
80 physid_mask_t phys_cpu_present_map;
83 * Processor to be disabled specified by kernel parameter
84 * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
85 * avoid undefined behaviour caused by sending INIT from AP to BSP.
87 static unsigned int disabled_cpu_apicid __read_mostly = BAD_APICID;
90 * This variable controls which CPUs receive external NMIs. By default,
91 * external NMIs are delivered only to the BSP.
93 static int apic_extnmi = APIC_EXTNMI_BSP;
96 * Map cpu index to physical APIC ID
98 DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
99 DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID);
100 DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX);
101 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
102 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
103 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
108 * On x86_32, the mapping between cpu and logical apicid may vary
109 * depending on apic in use. The following early percpu variable is
110 * used for the mapping. This is where the behaviors of x86_64 and 32
111 * actually diverge. Let's keep it ugly for now.
113 DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID);
115 /* Local APIC was disabled by the BIOS and enabled by the kernel */
116 static int enabled_via_apicbase;
119 * Handle interrupt mode configuration register (IMCR).
120 * This register controls whether the interrupt signals
121 * that reach the BSP come from the master PIC or from the
122 * local APIC. Before entering Symmetric I/O Mode, either
123 * the BIOS or the operating system must switch out of
124 * PIC Mode by changing the IMCR.
126 static inline void imcr_pic_to_apic(void)
128 /* select IMCR register */
130 /* NMI and 8259 INTR go through APIC */
134 static inline void imcr_apic_to_pic(void)
136 /* select IMCR register */
138 /* NMI and 8259 INTR go directly to BSP */
144 * Knob to control our willingness to enable the local APIC.
148 static int force_enable_local_apic __initdata;
151 * APIC command line parameters
153 static int __init parse_lapic(char *arg)
155 if (IS_ENABLED(CONFIG_X86_32) && !arg)
156 force_enable_local_apic = 1;
157 else if (arg && !strncmp(arg, "notscdeadline", 13))
158 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
161 early_param("lapic", parse_lapic);
164 static int apic_calibrate_pmtmr __initdata;
165 static __init int setup_apicpmtimer(char *s)
167 apic_calibrate_pmtmr = 1;
171 __setup("apicpmtimer", setup_apicpmtimer);
174 unsigned long mp_lapic_addr;
176 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
177 static int disable_apic_timer __initdata;
178 /* Local APIC timer works in C2 */
179 int local_apic_timer_c2_ok;
180 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
183 * Debug level, exported for io_apic.c
185 unsigned int apic_verbosity;
189 /* Have we found an MP table */
190 int smp_found_config;
192 static struct resource lapic_resource = {
193 .name = "Local APIC",
194 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
197 unsigned int lapic_timer_period = 0;
199 static void apic_pm_activate(void);
201 static unsigned long apic_phys;
204 * Get the LAPIC version
206 static inline int lapic_get_version(void)
208 return GET_APIC_VERSION(apic_read(APIC_LVR));
212 * Check, if the APIC is integrated or a separate chip
214 static inline int lapic_is_integrated(void)
216 return APIC_INTEGRATED(lapic_get_version());
220 * Check, whether this is a modern or a first generation APIC
222 static int modern_apic(void)
224 /* AMD systems use old APIC versions, so check the CPU */
225 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
226 boot_cpu_data.x86 >= 0xf)
229 /* Hygon systems use modern APIC */
230 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
233 return lapic_get_version() >= 0x14;
237 * right after this call apic become NOOP driven
238 * so apic->write/read doesn't do anything
240 static void __init apic_disable(void)
242 pr_info("APIC: switched to apic NOOP\n");
246 void native_apic_wait_icr_idle(void)
248 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
252 u32 native_safe_apic_wait_icr_idle(void)
259 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
262 inc_irq_stat(icr_read_retry_count);
264 } while (timeout++ < 1000);
269 void native_apic_icr_write(u32 low, u32 id)
273 local_irq_save(flags);
274 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
275 apic_write(APIC_ICR, low);
276 local_irq_restore(flags);
279 u64 native_apic_icr_read(void)
283 icr2 = apic_read(APIC_ICR2);
284 icr1 = apic_read(APIC_ICR);
286 return icr1 | ((u64)icr2 << 32);
291 * get_physical_broadcast - Get number of physical broadcast IDs
293 int get_physical_broadcast(void)
295 return modern_apic() ? 0xff : 0xf;
300 * lapic_get_maxlvt - get the maximum number of local vector table entries
302 int lapic_get_maxlvt(void)
305 * - we always have APIC integrated on 64bit mode
306 * - 82489DXs do not report # of LVT entries
308 return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2;
316 #define APIC_DIVISOR 16
317 #define TSC_DIVISOR 8
320 * This function sets up the local APIC timer, with a timeout of
321 * 'clocks' APIC bus clock. During calibration we actually call
322 * this function twice on the boot CPU, once with a bogus timeout
323 * value, second time for real. The other (noncalibrating) CPUs
324 * call this function only once, with the real, calibrated value.
326 * We do reads before writes even if unnecessary, to get around the
327 * P5 APIC double write bug.
329 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
331 unsigned int lvtt_value, tmp_value;
333 lvtt_value = LOCAL_TIMER_VECTOR;
335 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
336 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
337 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
339 if (!lapic_is_integrated())
340 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
343 lvtt_value |= APIC_LVT_MASKED;
345 apic_write(APIC_LVTT, lvtt_value);
347 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
349 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
350 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
351 * According to Intel, MFENCE can do the serialization here.
353 asm volatile("mfence" : : : "memory");
355 printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
362 tmp_value = apic_read(APIC_TDCR);
363 apic_write(APIC_TDCR,
364 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
368 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
372 * Setup extended LVT, AMD specific
374 * Software should use the LVT offsets the BIOS provides. The offsets
375 * are determined by the subsystems using it like those for MCE
376 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
377 * are supported. Beginning with family 10h at least 4 offsets are
380 * Since the offsets must be consistent for all cores, we keep track
381 * of the LVT offsets in software and reserve the offset for the same
382 * vector also to be used on other cores. An offset is freed by
383 * setting the entry to APIC_EILVT_MASKED.
385 * If the BIOS is right, there should be no conflicts. Otherwise a
386 * "[Firmware Bug]: ..." error message is generated. However, if
387 * software does not properly determines the offsets, it is not
388 * necessarily a BIOS bug.
391 static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
393 static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
395 return (old & APIC_EILVT_MASKED)
396 || (new == APIC_EILVT_MASKED)
397 || ((new & ~APIC_EILVT_MASKED) == old);
400 static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
402 unsigned int rsvd, vector;
404 if (offset >= APIC_EILVT_NR_MAX)
407 rsvd = atomic_read(&eilvt_offsets[offset]);
409 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
410 if (vector && !eilvt_entry_is_changeable(vector, new))
411 /* may not change if vectors are different */
413 rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
414 } while (rsvd != new);
416 rsvd &= ~APIC_EILVT_MASKED;
417 if (rsvd && rsvd != vector)
418 pr_info("LVT offset %d assigned for vector 0x%02x\n",
425 * If mask=1, the LVT entry does not generate interrupts while mask=0
426 * enables the vector. See also the BKDGs. Must be called with
427 * preemption disabled.
430 int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
432 unsigned long reg = APIC_EILVTn(offset);
433 unsigned int new, old, reserved;
435 new = (mask << 16) | (msg_type << 8) | vector;
436 old = apic_read(reg);
437 reserved = reserve_eilvt_offset(offset, new);
439 if (reserved != new) {
440 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
441 "vector 0x%x, but the register is already in use for "
442 "vector 0x%x on another cpu\n",
443 smp_processor_id(), reg, offset, new, reserved);
447 if (!eilvt_entry_is_changeable(old, new)) {
448 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
449 "vector 0x%x, but the register is already in use for "
450 "vector 0x%x on this cpu\n",
451 smp_processor_id(), reg, offset, new, old);
455 apic_write(reg, new);
459 EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
462 * Program the next event, relative to now
464 static int lapic_next_event(unsigned long delta,
465 struct clock_event_device *evt)
467 apic_write(APIC_TMICT, delta);
471 static int lapic_next_deadline(unsigned long delta,
472 struct clock_event_device *evt)
477 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
481 static int lapic_timer_shutdown(struct clock_event_device *evt)
485 /* Lapic used as dummy for broadcast ? */
486 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
489 v = apic_read(APIC_LVTT);
490 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
491 apic_write(APIC_LVTT, v);
492 apic_write(APIC_TMICT, 0);
497 lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
499 /* Lapic used as dummy for broadcast ? */
500 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
503 __setup_APIC_LVTT(lapic_timer_period, oneshot, 1);
507 static int lapic_timer_set_periodic(struct clock_event_device *evt)
509 return lapic_timer_set_periodic_oneshot(evt, false);
512 static int lapic_timer_set_oneshot(struct clock_event_device *evt)
514 return lapic_timer_set_periodic_oneshot(evt, true);
518 * Local APIC timer broadcast function
520 static void lapic_timer_broadcast(const struct cpumask *mask)
523 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
529 * The local apic timer can be used for any function which is CPU local.
531 static struct clock_event_device lapic_clockevent = {
533 .features = CLOCK_EVT_FEAT_PERIODIC |
534 CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
535 | CLOCK_EVT_FEAT_DUMMY,
537 .set_state_shutdown = lapic_timer_shutdown,
538 .set_state_periodic = lapic_timer_set_periodic,
539 .set_state_oneshot = lapic_timer_set_oneshot,
540 .set_state_oneshot_stopped = lapic_timer_shutdown,
541 .set_next_event = lapic_next_event,
542 .broadcast = lapic_timer_broadcast,
546 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
548 #define DEADLINE_MODEL_MATCH_FUNC(model, func) \
549 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&func }
551 #define DEADLINE_MODEL_MATCH_REV(model, rev) \
552 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)rev }
554 static u32 hsx_deadline_rev(void)
556 switch (boot_cpu_data.x86_stepping) {
557 case 0x02: return 0x3a; /* EP */
558 case 0x04: return 0x0f; /* EX */
564 static u32 bdx_deadline_rev(void)
566 switch (boot_cpu_data.x86_stepping) {
567 case 0x02: return 0x00000011;
568 case 0x03: return 0x0700000e;
569 case 0x04: return 0x0f00000c;
570 case 0x05: return 0x0e000003;
576 static u32 skx_deadline_rev(void)
578 switch (boot_cpu_data.x86_stepping) {
579 case 0x03: return 0x01000136;
580 case 0x04: return 0x02000014;
583 if (boot_cpu_data.x86_stepping > 4)
589 static const struct x86_cpu_id deadline_match[] = {
590 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_HASWELL_X, hsx_deadline_rev),
591 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_X, 0x0b000020),
592 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_BROADWELL_XEON_D, bdx_deadline_rev),
593 DEADLINE_MODEL_MATCH_FUNC( INTEL_FAM6_SKYLAKE_X, skx_deadline_rev),
595 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_CORE, 0x22),
596 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_ULT, 0x20),
597 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_HASWELL_GT3E, 0x17),
599 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_CORE, 0x25),
600 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_BROADWELL_GT3E, 0x17),
602 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_MOBILE, 0xb2),
603 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_SKYLAKE_DESKTOP, 0xb2),
605 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_MOBILE, 0x52),
606 DEADLINE_MODEL_MATCH_REV ( INTEL_FAM6_KABYLAKE_DESKTOP, 0x52),
611 static void apic_check_deadline_errata(void)
613 const struct x86_cpu_id *m;
616 if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER) ||
617 boot_cpu_has(X86_FEATURE_HYPERVISOR))
620 m = x86_match_cpu(deadline_match);
625 * Function pointers will have the MSB set due to address layout,
626 * immediate revisions will not.
628 if ((long)m->driver_data < 0)
629 rev = ((u32 (*)(void))(m->driver_data))();
631 rev = (u32)m->driver_data;
633 if (boot_cpu_data.microcode >= rev)
636 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
637 pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; "
638 "please update microcode to version: 0x%x (or later)\n", rev);
642 * Setup the local APIC timer for this CPU. Copy the initialized values
643 * of the boot CPU and register the clock event in the framework.
645 static void setup_APIC_timer(void)
647 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
649 if (this_cpu_has(X86_FEATURE_ARAT)) {
650 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
651 /* Make LAPIC timer preferrable over percpu HPET */
652 lapic_clockevent.rating = 150;
655 memcpy(levt, &lapic_clockevent, sizeof(*levt));
656 levt->cpumask = cpumask_of(smp_processor_id());
658 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
659 levt->name = "lapic-deadline";
660 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
661 CLOCK_EVT_FEAT_DUMMY);
662 levt->set_next_event = lapic_next_deadline;
663 clockevents_config_and_register(levt,
664 tsc_khz * (1000 / TSC_DIVISOR),
667 clockevents_register_device(levt);
671 * Install the updated TSC frequency from recalibration at the TSC
672 * deadline clockevent devices.
674 static void __lapic_update_tsc_freq(void *info)
676 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
678 if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
681 clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
684 void lapic_update_tsc_freq(void)
687 * The clockevent device's ->mult and ->shift can both be
688 * changed. In order to avoid races, schedule the frequency
689 * update code on each CPU.
691 on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
695 * In this functions we calibrate APIC bus clocks to the external timer.
697 * We want to do the calibration only once since we want to have local timer
698 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
701 * This was previously done by reading the PIT/HPET and waiting for a wrap
702 * around to find out, that a tick has elapsed. I have a box, where the PIT
703 * readout is broken, so it never gets out of the wait loop again. This was
704 * also reported by others.
706 * Monitoring the jiffies value is inaccurate and the clockevents
707 * infrastructure allows us to do a simple substitution of the interrupt
710 * The calibration routine also uses the pm_timer when possible, as the PIT
711 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
712 * back to normal later in the boot process).
715 #define LAPIC_CAL_LOOPS (HZ/10)
717 static __initdata int lapic_cal_loops = -1;
718 static __initdata long lapic_cal_t1, lapic_cal_t2;
719 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
720 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
721 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
724 * Temporary interrupt handler.
726 static void __init lapic_cal_handler(struct clock_event_device *dev)
728 unsigned long long tsc = 0;
729 long tapic = apic_read(APIC_TMCCT);
730 unsigned long pm = acpi_pm_read_early();
732 if (boot_cpu_has(X86_FEATURE_TSC))
735 switch (lapic_cal_loops++) {
737 lapic_cal_t1 = tapic;
738 lapic_cal_tsc1 = tsc;
740 lapic_cal_j1 = jiffies;
743 case LAPIC_CAL_LOOPS:
744 lapic_cal_t2 = tapic;
745 lapic_cal_tsc2 = tsc;
746 if (pm < lapic_cal_pm1)
747 pm += ACPI_PM_OVRRUN;
749 lapic_cal_j2 = jiffies;
755 calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
757 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
758 const long pm_thresh = pm_100ms / 100;
762 #ifndef CONFIG_X86_PM_TIMER
766 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
768 /* Check, if the PM timer is available */
772 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
774 if (deltapm > (pm_100ms - pm_thresh) &&
775 deltapm < (pm_100ms + pm_thresh)) {
776 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
780 res = (((u64)deltapm) * mult) >> 22;
781 do_div(res, 1000000);
782 pr_warning("APIC calibration not consistent "
783 "with PM-Timer: %ldms instead of 100ms\n",(long)res);
785 /* Correct the lapic counter value */
786 res = (((u64)(*delta)) * pm_100ms);
787 do_div(res, deltapm);
788 pr_info("APIC delta adjusted to PM-Timer: "
789 "%lu (%ld)\n", (unsigned long)res, *delta);
792 /* Correct the tsc counter value */
793 if (boot_cpu_has(X86_FEATURE_TSC)) {
794 res = (((u64)(*deltatsc)) * pm_100ms);
795 do_div(res, deltapm);
796 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
797 "PM-Timer: %lu (%ld)\n",
798 (unsigned long)res, *deltatsc);
799 *deltatsc = (long)res;
805 static int __init lapic_init_clockevent(void)
807 if (!lapic_timer_period)
810 /* Calculate the scaled math multiplication factor */
811 lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR,
812 TICK_NSEC, lapic_clockevent.shift);
813 lapic_clockevent.max_delta_ns =
814 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
815 lapic_clockevent.max_delta_ticks = 0x7FFFFFFF;
816 lapic_clockevent.min_delta_ns =
817 clockevent_delta2ns(0xF, &lapic_clockevent);
818 lapic_clockevent.min_delta_ticks = 0xF;
823 bool __init apic_needs_pit(void)
826 * If the frequencies are not known, PIT is required for both TSC
827 * and apic timer calibration.
829 if (!tsc_khz || !cpu_khz)
832 /* Is there an APIC at all? */
833 if (!boot_cpu_has(X86_FEATURE_APIC))
836 /* Deadline timer is based on TSC so no further PIT action required */
837 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
840 /* APIC timer disabled? */
841 if (disable_apic_timer)
844 * The APIC timer frequency is known already, no PIT calibration
845 * required. If unknown, let the PIT be initialized.
847 return lapic_timer_period == 0;
850 static int __init calibrate_APIC_clock(void)
852 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
853 void (*real_handler)(struct clock_event_device *dev);
854 unsigned long deltaj;
855 long delta, deltatsc;
856 int pm_referenced = 0;
858 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
862 * Check if lapic timer has already been calibrated by platform
863 * specific routine, such as tsc calibration code. If so just fill
864 * in the clockevent structure and return.
866 if (!lapic_init_clockevent()) {
867 apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
870 * Direct calibration methods must have an always running
871 * local APIC timer, no need for broadcast timer.
873 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
877 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
878 "calibrating APIC timer ...\n");
882 /* Replace the global interrupt handler */
883 real_handler = global_clock_event->event_handler;
884 global_clock_event->event_handler = lapic_cal_handler;
887 * Setup the APIC counter to maximum. There is no way the lapic
888 * can underflow in the 100ms detection time frame
890 __setup_APIC_LVTT(0xffffffff, 0, 0);
892 /* Let the interrupts run */
895 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
900 /* Restore the real event handler */
901 global_clock_event->event_handler = real_handler;
903 /* Build delta t1-t2 as apic timer counts down */
904 delta = lapic_cal_t1 - lapic_cal_t2;
905 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
907 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
909 /* we trust the PM based calibration if possible */
910 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
913 lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
914 lapic_init_clockevent();
916 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
917 apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
918 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
921 if (boot_cpu_has(X86_FEATURE_TSC)) {
922 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
924 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
925 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
928 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
930 lapic_timer_period / (1000000 / HZ),
931 lapic_timer_period % (1000000 / HZ));
934 * Do a sanity check on the APIC calibration result
936 if (lapic_timer_period < (1000000 / HZ)) {
938 pr_warning("APIC frequency too slow, disabling apic timer\n");
942 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
945 * PM timer calibration failed or not turned on
946 * so lets try APIC timer based calibration
948 if (!pm_referenced) {
949 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
952 * Setup the apic timer manually
954 levt->event_handler = lapic_cal_handler;
955 lapic_timer_set_periodic(levt);
956 lapic_cal_loops = -1;
958 /* Let the interrupts run */
961 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
964 /* Stop the lapic timer */
966 lapic_timer_shutdown(levt);
969 deltaj = lapic_cal_j2 - lapic_cal_j1;
970 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
972 /* Check, if the jiffies result is consistent */
973 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
974 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
976 levt->features |= CLOCK_EVT_FEAT_DUMMY;
980 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
981 pr_warning("APIC timer disabled due to verification failure\n");
989 * Setup the boot APIC
991 * Calibrate and verify the result.
993 void __init setup_boot_APIC_clock(void)
996 * The local apic timer can be disabled via the kernel
997 * commandline or from the CPU detection code. Register the lapic
998 * timer as a dummy clock event source on SMP systems, so the
999 * broadcast mechanism is used. On UP systems simply ignore it.
1001 if (disable_apic_timer) {
1002 pr_info("Disabling APIC timer\n");
1003 /* No broadcast on UP ! */
1004 if (num_possible_cpus() > 1) {
1005 lapic_clockevent.mult = 1;
1011 if (calibrate_APIC_clock()) {
1012 /* No broadcast on UP ! */
1013 if (num_possible_cpus() > 1)
1019 * If nmi_watchdog is set to IO_APIC, we need the
1020 * PIT/HPET going. Otherwise register lapic as a dummy
1023 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
1025 /* Setup the lapic or request the broadcast */
1027 amd_e400_c1e_apic_setup();
1030 void setup_secondary_APIC_clock(void)
1033 amd_e400_c1e_apic_setup();
1037 * The guts of the apic timer interrupt
1039 static void local_apic_timer_interrupt(void)
1041 struct clock_event_device *evt = this_cpu_ptr(&lapic_events);
1044 * Normally we should not be here till LAPIC has been initialized but
1045 * in some cases like kdump, its possible that there is a pending LAPIC
1046 * timer interrupt from previous kernel's context and is delivered in
1047 * new kernel the moment interrupts are enabled.
1049 * Interrupts are enabled early and LAPIC is setup much later, hence
1050 * its possible that when we get here evt->event_handler is NULL.
1051 * Check for event_handler being NULL and discard the interrupt as
1054 if (!evt->event_handler) {
1055 pr_warning("Spurious LAPIC timer interrupt on cpu %d\n",
1056 smp_processor_id());
1058 lapic_timer_shutdown(evt);
1063 * the NMI deadlock-detector uses this.
1065 inc_irq_stat(apic_timer_irqs);
1067 evt->event_handler(evt);
1071 * Local APIC timer interrupt. This is the most natural way for doing
1072 * local interrupts, but local timer interrupts can be emulated by
1073 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
1075 * [ if a single-CPU system runs an SMP kernel then we call the local
1076 * interrupt as well. Thus we cannot inline the local irq ... ]
1078 __visible void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
1080 struct pt_regs *old_regs = set_irq_regs(regs);
1083 * NOTE! We'd better ACK the irq immediately,
1084 * because timer handling can be slow.
1086 * update_process_times() expects us to have done irq_enter().
1087 * Besides, if we don't timer interrupts ignore the global
1088 * interrupt lock, which is the WrongThing (tm) to do.
1091 trace_local_timer_entry(LOCAL_TIMER_VECTOR);
1092 local_apic_timer_interrupt();
1093 trace_local_timer_exit(LOCAL_TIMER_VECTOR);
1096 set_irq_regs(old_regs);
1099 int setup_profiling_timer(unsigned int multiplier)
1105 * Local APIC start and shutdown
1109 * clear_local_APIC - shutdown the local APIC
1111 * This is called, when a CPU is disabled and before rebooting, so the state of
1112 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
1113 * leftovers during boot.
1115 void clear_local_APIC(void)
1120 /* APIC hasn't been mapped yet */
1121 if (!x2apic_mode && !apic_phys)
1124 maxlvt = lapic_get_maxlvt();
1126 * Masking an LVT entry can trigger a local APIC error
1127 * if the vector is zero. Mask LVTERR first to prevent this.
1130 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
1131 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
1134 * Careful: we have to set masks only first to deassert
1135 * any level-triggered sources.
1137 v = apic_read(APIC_LVTT);
1138 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
1139 v = apic_read(APIC_LVT0);
1140 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1141 v = apic_read(APIC_LVT1);
1142 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1144 v = apic_read(APIC_LVTPC);
1145 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1148 /* lets not touch this if we didn't frob it */
1149 #ifdef CONFIG_X86_THERMAL_VECTOR
1151 v = apic_read(APIC_LVTTHMR);
1152 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1155 #ifdef CONFIG_X86_MCE_INTEL
1157 v = apic_read(APIC_LVTCMCI);
1158 if (!(v & APIC_LVT_MASKED))
1159 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1164 * Clean APIC state for other OSs:
1166 apic_write(APIC_LVTT, APIC_LVT_MASKED);
1167 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1168 apic_write(APIC_LVT1, APIC_LVT_MASKED);
1170 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1172 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1174 /* Integrated APIC (!82489DX) ? */
1175 if (lapic_is_integrated()) {
1177 /* Clear ESR due to Pentium errata 3AP and 11AP */
1178 apic_write(APIC_ESR, 0);
1179 apic_read(APIC_ESR);
1184 * disable_local_APIC - clear and disable the local APIC
1186 void disable_local_APIC(void)
1190 /* APIC hasn't been mapped yet */
1191 if (!x2apic_mode && !apic_phys)
1197 * Disable APIC (implies clearing of registers
1200 value = apic_read(APIC_SPIV);
1201 value &= ~APIC_SPIV_APIC_ENABLED;
1202 apic_write(APIC_SPIV, value);
1204 #ifdef CONFIG_X86_32
1206 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1207 * restore the disabled state.
1209 if (enabled_via_apicbase) {
1212 rdmsr(MSR_IA32_APICBASE, l, h);
1213 l &= ~MSR_IA32_APICBASE_ENABLE;
1214 wrmsr(MSR_IA32_APICBASE, l, h);
1220 * If Linux enabled the LAPIC against the BIOS default disable it down before
1221 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
1222 * not power-off. Additionally clear all LVT entries before disable_local_APIC
1223 * for the case where Linux didn't enable the LAPIC.
1225 void lapic_shutdown(void)
1227 unsigned long flags;
1229 if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
1232 local_irq_save(flags);
1234 #ifdef CONFIG_X86_32
1235 if (!enabled_via_apicbase)
1239 disable_local_APIC();
1242 local_irq_restore(flags);
1246 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1248 void __init sync_Arb_IDs(void)
1251 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1254 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1260 apic_wait_icr_idle();
1262 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1263 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1264 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1267 enum apic_intr_mode_id apic_intr_mode;
1269 static int __init apic_intr_mode_select(void)
1271 /* Check kernel option */
1273 pr_info("APIC disabled via kernel command line\n");
1278 #ifdef CONFIG_X86_64
1279 /* On 64-bit, the APIC must be integrated, Check local APIC only */
1280 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1282 pr_info("APIC disabled by BIOS\n");
1286 /* On 32-bit, the APIC may be integrated APIC or 82489DX */
1288 /* Neither 82489DX nor integrated APIC ? */
1289 if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) {
1294 /* If the BIOS pretends there is an integrated APIC ? */
1295 if (!boot_cpu_has(X86_FEATURE_APIC) &&
1296 APIC_INTEGRATED(boot_cpu_apic_version)) {
1298 pr_err(FW_BUG "Local APIC %d not detected, force emulation\n",
1299 boot_cpu_physical_apicid);
1304 /* Check MP table or ACPI MADT configuration */
1305 if (!smp_found_config) {
1306 disable_ioapic_support();
1308 pr_info("APIC: ACPI MADT or MP tables are not detected\n");
1309 return APIC_VIRTUAL_WIRE_NO_CONFIG;
1311 return APIC_VIRTUAL_WIRE;
1315 /* If SMP should be disabled, then really disable it! */
1316 if (!setup_max_cpus) {
1317 pr_info("APIC: SMP mode deactivated\n");
1318 return APIC_SYMMETRIC_IO_NO_ROUTING;
1321 if (read_apic_id() != boot_cpu_physical_apicid) {
1322 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
1323 read_apic_id(), boot_cpu_physical_apicid);
1324 /* Or can we switch back to PIC here? */
1328 return APIC_SYMMETRIC_IO;
1332 * An initial setup of the virtual wire mode.
1334 void __init init_bsp_APIC(void)
1339 * Don't do the setup now if we have a SMP BIOS as the
1340 * through-I/O-APIC virtual wire mode might be active.
1342 if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
1346 * Do not trust the local APIC being empty at bootup.
1353 value = apic_read(APIC_SPIV);
1354 value &= ~APIC_VECTOR_MASK;
1355 value |= APIC_SPIV_APIC_ENABLED;
1357 #ifdef CONFIG_X86_32
1358 /* This bit is reserved on P4/Xeon and should be cleared */
1359 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1360 (boot_cpu_data.x86 == 15))
1361 value &= ~APIC_SPIV_FOCUS_DISABLED;
1364 value |= APIC_SPIV_FOCUS_DISABLED;
1365 value |= SPURIOUS_APIC_VECTOR;
1366 apic_write(APIC_SPIV, value);
1369 * Set up the virtual wire mode.
1371 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1372 value = APIC_DM_NMI;
1373 if (!lapic_is_integrated()) /* 82489DX */
1374 value |= APIC_LVT_LEVEL_TRIGGER;
1375 if (apic_extnmi == APIC_EXTNMI_NONE)
1376 value |= APIC_LVT_MASKED;
1377 apic_write(APIC_LVT1, value);
1380 static void __init apic_bsp_setup(bool upmode);
1382 /* Init the interrupt delivery mode for the BSP */
1383 void __init apic_intr_mode_init(void)
1385 bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
1387 apic_intr_mode = apic_intr_mode_select();
1389 switch (apic_intr_mode) {
1391 pr_info("APIC: Keep in PIC mode(8259)\n");
1393 case APIC_VIRTUAL_WIRE:
1394 pr_info("APIC: Switch to virtual wire mode setup\n");
1395 default_setup_apic_routing();
1397 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1398 pr_info("APIC: Switch to virtual wire mode setup with no configuration\n");
1400 default_setup_apic_routing();
1402 case APIC_SYMMETRIC_IO:
1403 pr_info("APIC: Switch to symmetric I/O mode setup\n");
1404 default_setup_apic_routing();
1406 case APIC_SYMMETRIC_IO_NO_ROUTING:
1407 pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n");
1411 apic_bsp_setup(upmode);
1414 static void lapic_setup_esr(void)
1416 unsigned int oldvalue, value, maxlvt;
1418 if (!lapic_is_integrated()) {
1419 pr_info("No ESR for 82489DX.\n");
1423 if (apic->disable_esr) {
1425 * Something untraceable is creating bad interrupts on
1426 * secondary quads ... for the moment, just leave the
1427 * ESR disabled - we can't do anything useful with the
1428 * errors anyway - mbligh
1430 pr_info("Leaving ESR disabled.\n");
1434 maxlvt = lapic_get_maxlvt();
1435 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1436 apic_write(APIC_ESR, 0);
1437 oldvalue = apic_read(APIC_ESR);
1439 /* enables sending errors */
1440 value = ERROR_APIC_VECTOR;
1441 apic_write(APIC_LVTERR, value);
1444 * spec says clear errors after enabling vector.
1447 apic_write(APIC_ESR, 0);
1448 value = apic_read(APIC_ESR);
1449 if (value != oldvalue)
1450 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1451 "vector: 0x%08x after: 0x%08x\n",
1455 static void apic_pending_intr_clear(void)
1457 long long max_loops = cpu_khz ? cpu_khz : 1000000;
1458 unsigned long long tsc = 0, ntsc;
1459 unsigned int queued;
1460 unsigned long value;
1461 int i, j, acked = 0;
1463 if (boot_cpu_has(X86_FEATURE_TSC))
1466 * After a crash, we no longer service the interrupts and a pending
1467 * interrupt from previous kernel might still have ISR bit set.
1469 * Most probably by now CPU has serviced that pending interrupt and
1470 * it might not have done the ack_APIC_irq() because it thought,
1471 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1472 * does not clear the ISR bit and cpu thinks it has already serivced
1473 * the interrupt. Hence a vector might get locked. It was noticed
1474 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1478 for (i = APIC_ISR_NR - 1; i >= 0; i--)
1479 queued |= apic_read(APIC_IRR + i*0x10);
1481 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1482 value = apic_read(APIC_ISR + i*0x10);
1483 for_each_set_bit(j, &value, 32) {
1489 pr_err("LAPIC pending interrupts after %d EOI\n", acked);
1493 if (boot_cpu_has(X86_FEATURE_TSC) && cpu_khz) {
1495 max_loops = (cpu_khz << 10) - (ntsc - tsc);
1500 } while (queued && max_loops > 0);
1501 WARN_ON(max_loops <= 0);
1505 * setup_local_APIC - setup the local APIC
1507 * Used to setup local APIC while initializing BSP or bringing up APs.
1508 * Always called with preemption disabled.
1510 static void setup_local_APIC(void)
1512 int cpu = smp_processor_id();
1514 #ifdef CONFIG_X86_32
1515 int logical_apicid, ldr_apicid;
1520 disable_ioapic_support();
1524 #ifdef CONFIG_X86_32
1525 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1526 if (lapic_is_integrated() && apic->disable_esr) {
1527 apic_write(APIC_ESR, 0);
1528 apic_write(APIC_ESR, 0);
1529 apic_write(APIC_ESR, 0);
1530 apic_write(APIC_ESR, 0);
1533 perf_events_lapic_init();
1536 * Double-check whether this APIC is really registered.
1537 * This is meaningless in clustered apic mode, so we skip it.
1539 BUG_ON(!apic->apic_id_registered());
1542 * Intel recommends to set DFR, LDR and TPR before enabling
1543 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1544 * document number 292116). So here it goes...
1546 apic->init_apic_ldr();
1548 #ifdef CONFIG_X86_32
1550 * APIC LDR is initialized. If logical_apicid mapping was
1551 * initialized during get_smp_config(), make sure it matches the
1554 logical_apicid = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
1555 ldr_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1556 WARN_ON(logical_apicid != BAD_APICID && logical_apicid != ldr_apicid);
1557 /* always use the value from LDR */
1558 early_per_cpu(x86_cpu_to_logical_apicid, cpu) = ldr_apicid;
1562 * Set Task Priority to 'accept all'. We never change this
1565 value = apic_read(APIC_TASKPRI);
1566 value &= ~APIC_TPRI_MASK;
1567 apic_write(APIC_TASKPRI, value);
1569 apic_pending_intr_clear();
1572 * Now that we are all set up, enable the APIC
1574 value = apic_read(APIC_SPIV);
1575 value &= ~APIC_VECTOR_MASK;
1579 value |= APIC_SPIV_APIC_ENABLED;
1581 #ifdef CONFIG_X86_32
1583 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1584 * certain networking cards. If high frequency interrupts are
1585 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1586 * entry is masked/unmasked at a high rate as well then sooner or
1587 * later IOAPIC line gets 'stuck', no more interrupts are received
1588 * from the device. If focus CPU is disabled then the hang goes
1591 * [ This bug can be reproduced easily with a level-triggered
1592 * PCI Ne2000 networking cards and PII/PIII processors, dual
1596 * Actually disabling the focus CPU check just makes the hang less
1597 * frequent as it makes the interrupt distributon model be more
1598 * like LRU than MRU (the short-term load is more even across CPUs).
1602 * - enable focus processor (bit==0)
1603 * - 64bit mode always use processor focus
1604 * so no need to set it
1606 value &= ~APIC_SPIV_FOCUS_DISABLED;
1610 * Set spurious IRQ vector
1612 value |= SPURIOUS_APIC_VECTOR;
1613 apic_write(APIC_SPIV, value);
1616 * Set up LVT0, LVT1:
1618 * set up through-local-APIC on the boot CPU's LINT0. This is not
1619 * strictly necessary in pure symmetric-IO mode, but sometimes
1620 * we delegate interrupts to the 8259A.
1623 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1625 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1626 if (!cpu && (pic_mode || !value || skip_ioapic_setup)) {
1627 value = APIC_DM_EXTINT;
1628 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1630 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1631 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1633 apic_write(APIC_LVT0, value);
1636 * Only the BSP sees the LINT1 NMI signal by default. This can be
1637 * modified by apic_extnmi= boot option.
1639 if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1640 apic_extnmi == APIC_EXTNMI_ALL)
1641 value = APIC_DM_NMI;
1643 value = APIC_DM_NMI | APIC_LVT_MASKED;
1646 if (!lapic_is_integrated())
1647 value |= APIC_LVT_LEVEL_TRIGGER;
1648 apic_write(APIC_LVT1, value);
1650 #ifdef CONFIG_X86_MCE_INTEL
1651 /* Recheck CMCI information after local APIC is up on CPU #0 */
1657 static void end_local_APIC_setup(void)
1661 #ifdef CONFIG_X86_32
1664 /* Disable the local apic timer */
1665 value = apic_read(APIC_LVTT);
1666 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1667 apic_write(APIC_LVTT, value);
1675 * APIC setup function for application processors. Called from smpboot.c
1677 void apic_ap_setup(void)
1680 end_local_APIC_setup();
1683 #ifdef CONFIG_X86_X2APIC
1691 static int x2apic_state;
1693 static void __x2apic_disable(void)
1697 if (!boot_cpu_has(X86_FEATURE_APIC))
1700 rdmsrl(MSR_IA32_APICBASE, msr);
1701 if (!(msr & X2APIC_ENABLE))
1703 /* Disable xapic and x2apic first and then reenable xapic mode */
1704 wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1705 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1706 printk_once(KERN_INFO "x2apic disabled\n");
1709 static void __x2apic_enable(void)
1713 rdmsrl(MSR_IA32_APICBASE, msr);
1714 if (msr & X2APIC_ENABLE)
1716 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1717 printk_once(KERN_INFO "x2apic enabled\n");
1720 static int __init setup_nox2apic(char *str)
1722 if (x2apic_enabled()) {
1723 int apicid = native_apic_msr_read(APIC_ID);
1725 if (apicid >= 255) {
1726 pr_warning("Apicid: %08x, cannot enforce nox2apic\n",
1730 pr_warning("x2apic already enabled.\n");
1733 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1734 x2apic_state = X2APIC_DISABLED;
1738 early_param("nox2apic", setup_nox2apic);
1740 /* Called from cpu_init() to enable x2apic on (secondary) cpus */
1741 void x2apic_setup(void)
1744 * If x2apic is not in ON state, disable it if already enabled
1747 if (x2apic_state != X2APIC_ON) {
1754 static __init void x2apic_disable(void)
1756 u32 x2apic_id, state = x2apic_state;
1759 x2apic_state = X2APIC_DISABLED;
1761 if (state != X2APIC_ON)
1764 x2apic_id = read_apic_id();
1765 if (x2apic_id >= 255)
1766 panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1769 register_lapic_address(mp_lapic_addr);
1772 static __init void x2apic_enable(void)
1774 if (x2apic_state != X2APIC_OFF)
1778 x2apic_state = X2APIC_ON;
1782 static __init void try_to_enable_x2apic(int remap_mode)
1784 if (x2apic_state == X2APIC_DISABLED)
1787 if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1788 /* IR is required if there is APIC ID > 255 even when running
1791 if (max_physical_apicid > 255 ||
1792 !x86_init.hyper.x2apic_available()) {
1793 pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1799 * without IR all CPUs can be addressed by IOAPIC/MSI
1800 * only in physical mode
1807 void __init check_x2apic(void)
1809 if (x2apic_enabled()) {
1810 pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1812 x2apic_state = X2APIC_ON;
1813 } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) {
1814 x2apic_state = X2APIC_DISABLED;
1817 #else /* CONFIG_X86_X2APIC */
1818 static int __init validate_x2apic(void)
1820 if (!apic_is_x2apic_enabled())
1823 * Checkme: Can we simply turn off x2apic here instead of panic?
1825 panic("BIOS has enabled x2apic but kernel doesn't support x2apic, please disable x2apic in BIOS.\n");
1827 early_initcall(validate_x2apic);
1829 static inline void try_to_enable_x2apic(int remap_mode) { }
1830 static inline void __x2apic_enable(void) { }
1831 #endif /* !CONFIG_X86_X2APIC */
1833 void __init enable_IR_x2apic(void)
1835 unsigned long flags;
1838 if (skip_ioapic_setup) {
1839 pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1843 ir_stat = irq_remapping_prepare();
1844 if (ir_stat < 0 && !x2apic_supported())
1847 ret = save_ioapic_entries();
1849 pr_info("Saving IO-APIC state failed: %d\n", ret);
1853 local_irq_save(flags);
1854 legacy_pic->mask_all();
1855 mask_ioapic_entries();
1857 /* If irq_remapping_prepare() succeeded, try to enable it */
1859 ir_stat = irq_remapping_enable();
1860 /* ir_stat contains the remap mode or an error code */
1861 try_to_enable_x2apic(ir_stat);
1864 restore_ioapic_entries();
1865 legacy_pic->restore_mask();
1866 local_irq_restore(flags);
1869 #ifdef CONFIG_X86_64
1871 * Detect and enable local APICs on non-SMP boards.
1872 * Original code written by Keir Fraser.
1873 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1874 * not correctly set up (usually the APIC timer won't work etc.)
1876 static int __init detect_init_APIC(void)
1878 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1879 pr_info("No local APIC present\n");
1883 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1888 static int __init apic_verify(void)
1893 * The APIC feature bit should now be enabled
1896 features = cpuid_edx(1);
1897 if (!(features & (1 << X86_FEATURE_APIC))) {
1898 pr_warning("Could not enable APIC!\n");
1901 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1902 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1904 /* The BIOS may have set up the APIC at some other address */
1905 if (boot_cpu_data.x86 >= 6) {
1906 rdmsr(MSR_IA32_APICBASE, l, h);
1907 if (l & MSR_IA32_APICBASE_ENABLE)
1908 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1911 pr_info("Found and enabled local APIC!\n");
1915 int __init apic_force_enable(unsigned long addr)
1923 * Some BIOSes disable the local APIC in the APIC_BASE
1924 * MSR. This can only be done in software for Intel P6 or later
1925 * and AMD K7 (Model > 1) or later.
1927 if (boot_cpu_data.x86 >= 6) {
1928 rdmsr(MSR_IA32_APICBASE, l, h);
1929 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1930 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1931 l &= ~MSR_IA32_APICBASE_BASE;
1932 l |= MSR_IA32_APICBASE_ENABLE | addr;
1933 wrmsr(MSR_IA32_APICBASE, l, h);
1934 enabled_via_apicbase = 1;
1937 return apic_verify();
1941 * Detect and initialize APIC
1943 static int __init detect_init_APIC(void)
1945 /* Disabled by kernel option? */
1949 switch (boot_cpu_data.x86_vendor) {
1950 case X86_VENDOR_AMD:
1951 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1952 (boot_cpu_data.x86 >= 15))
1955 case X86_VENDOR_HYGON:
1957 case X86_VENDOR_INTEL:
1958 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1959 (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC)))
1966 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1968 * Over-ride BIOS and try to enable the local APIC only if
1969 * "lapic" specified.
1971 if (!force_enable_local_apic) {
1972 pr_info("Local APIC disabled by BIOS -- "
1973 "you can enable it with \"lapic\"\n");
1976 if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
1988 pr_info("No local APIC present or hardware disabled\n");
1994 * init_apic_mappings - initialize APIC mappings
1996 void __init init_apic_mappings(void)
1998 unsigned int new_apicid;
2000 apic_check_deadline_errata();
2003 boot_cpu_physical_apicid = read_apic_id();
2007 /* If no local APIC can be found return early */
2008 if (!smp_found_config && detect_init_APIC()) {
2009 /* lets NOP'ify apic operations */
2010 pr_info("APIC: disable apic facility\n");
2013 apic_phys = mp_lapic_addr;
2016 * If the system has ACPI MADT tables or MP info, the LAPIC
2017 * address is already registered.
2019 if (!acpi_lapic && !smp_found_config)
2020 register_lapic_address(apic_phys);
2024 * Fetch the APIC ID of the BSP in case we have a
2025 * default configuration (or the MP table is broken).
2027 new_apicid = read_apic_id();
2028 if (boot_cpu_physical_apicid != new_apicid) {
2029 boot_cpu_physical_apicid = new_apicid;
2031 * yeah -- we lie about apic_version
2032 * in case if apic was disabled via boot option
2033 * but it's not a problem for SMP compiled kernel
2034 * since apic_intr_mode_select is prepared for such
2035 * a case and disable smp mode
2037 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2041 void __init register_lapic_address(unsigned long address)
2043 mp_lapic_addr = address;
2046 set_fixmap_nocache(FIX_APIC_BASE, address);
2047 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
2048 APIC_BASE, address);
2050 if (boot_cpu_physical_apicid == -1U) {
2051 boot_cpu_physical_apicid = read_apic_id();
2052 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2057 * Local APIC interrupts
2061 * This interrupt should _never_ happen with our APIC/SMP architecture
2063 __visible void __irq_entry smp_spurious_interrupt(struct pt_regs *regs)
2065 u8 vector = ~regs->orig_ax;
2069 trace_spurious_apic_entry(vector);
2071 inc_irq_stat(irq_spurious_count);
2074 * If this is a spurious interrupt then do not acknowledge
2076 if (vector == SPURIOUS_APIC_VECTOR) {
2078 pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n",
2079 smp_processor_id());
2084 * If it is a vectored one, verify it's set in the ISR. If set,
2087 v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
2088 if (v & (1 << (vector & 0x1f))) {
2089 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
2090 vector, smp_processor_id());
2093 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
2094 vector, smp_processor_id());
2097 trace_spurious_apic_exit(vector);
2102 * This interrupt should never happen with our APIC/SMP architecture
2104 __visible void __irq_entry smp_error_interrupt(struct pt_regs *regs)
2106 static const char * const error_interrupt_reason[] = {
2107 "Send CS error", /* APIC Error Bit 0 */
2108 "Receive CS error", /* APIC Error Bit 1 */
2109 "Send accept error", /* APIC Error Bit 2 */
2110 "Receive accept error", /* APIC Error Bit 3 */
2111 "Redirectable IPI", /* APIC Error Bit 4 */
2112 "Send illegal vector", /* APIC Error Bit 5 */
2113 "Received illegal vector", /* APIC Error Bit 6 */
2114 "Illegal register address", /* APIC Error Bit 7 */
2119 trace_error_apic_entry(ERROR_APIC_VECTOR);
2121 /* First tickle the hardware, only then report what went on. -- REW */
2122 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */
2123 apic_write(APIC_ESR, 0);
2124 v = apic_read(APIC_ESR);
2126 atomic_inc(&irq_err_count);
2128 apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
2129 smp_processor_id(), v);
2134 apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
2139 apic_printk(APIC_DEBUG, KERN_CONT "\n");
2141 trace_error_apic_exit(ERROR_APIC_VECTOR);
2146 * connect_bsp_APIC - attach the APIC to the interrupt system
2148 static void __init connect_bsp_APIC(void)
2150 #ifdef CONFIG_X86_32
2153 * Do not trust the local APIC being empty at bootup.
2157 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
2158 * local APIC to INT and NMI lines.
2160 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
2161 "enabling APIC mode.\n");
2168 * disconnect_bsp_APIC - detach the APIC from the interrupt system
2169 * @virt_wire_setup: indicates, whether virtual wire mode is selected
2171 * Virtual wire mode is necessary to deliver legacy interrupts even when the
2174 void disconnect_bsp_APIC(int virt_wire_setup)
2178 #ifdef CONFIG_X86_32
2181 * Put the board back into PIC mode (has an effect only on
2182 * certain older boards). Note that APIC interrupts, including
2183 * IPIs, won't work beyond this point! The only exception are
2186 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
2187 "entering PIC mode.\n");
2193 /* Go back to Virtual Wire compatibility mode */
2195 /* For the spurious interrupt use vector F, and enable it */
2196 value = apic_read(APIC_SPIV);
2197 value &= ~APIC_VECTOR_MASK;
2198 value |= APIC_SPIV_APIC_ENABLED;
2200 apic_write(APIC_SPIV, value);
2202 if (!virt_wire_setup) {
2204 * For LVT0 make it edge triggered, active high,
2205 * external and enabled
2207 value = apic_read(APIC_LVT0);
2208 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2209 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2210 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2211 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2212 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2213 apic_write(APIC_LVT0, value);
2216 apic_write(APIC_LVT0, APIC_LVT_MASKED);
2220 * For LVT1 make it edge triggered, active high,
2223 value = apic_read(APIC_LVT1);
2224 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2225 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2226 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2227 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2228 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2229 apic_write(APIC_LVT1, value);
2233 * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
2234 * contiguously, it equals to current allocated max logical CPU ID plus 1.
2235 * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range,
2236 * so the maximum of nr_logical_cpuids is nr_cpu_ids.
2238 * NOTE: Reserve 0 for BSP.
2240 static int nr_logical_cpuids = 1;
2243 * Used to store mapping between logical CPU IDs and APIC IDs.
2245 static int cpuid_to_apicid[] = {
2246 [0 ... NR_CPUS - 1] = -1,
2251 * apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread
2252 * @id: APIC ID to check
2254 bool apic_id_is_primary_thread(unsigned int apicid)
2258 if (smp_num_siblings == 1)
2260 /* Isolate the SMT bit(s) in the APICID and check for 0 */
2261 mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
2262 return !(apicid & mask);
2267 * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
2268 * and cpuid_to_apicid[] synchronized.
2270 static int allocate_logical_cpuid(int apicid)
2275 * cpuid <-> apicid mapping is persistent, so when a cpu is up,
2276 * check if the kernel has allocated a cpuid for it.
2278 for (i = 0; i < nr_logical_cpuids; i++) {
2279 if (cpuid_to_apicid[i] == apicid)
2283 /* Allocate a new cpuid. */
2284 if (nr_logical_cpuids >= nr_cpu_ids) {
2285 WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
2286 "Processor %d/0x%x and the rest are ignored.\n",
2287 nr_cpu_ids, nr_logical_cpuids, apicid);
2291 cpuid_to_apicid[nr_logical_cpuids] = apicid;
2292 return nr_logical_cpuids++;
2295 int generic_processor_info(int apicid, int version)
2297 int cpu, max = nr_cpu_ids;
2298 bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
2299 phys_cpu_present_map);
2302 * boot_cpu_physical_apicid is designed to have the apicid
2303 * returned by read_apic_id(), i.e, the apicid of the
2304 * currently booting-up processor. However, on some platforms,
2305 * it is temporarily modified by the apicid reported as BSP
2306 * through MP table. Concretely:
2308 * - arch/x86/kernel/mpparse.c: MP_processor_info()
2309 * - arch/x86/mm/amdtopology.c: amd_numa_init()
2311 * This function is executed with the modified
2312 * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel
2313 * parameter doesn't work to disable APs on kdump 2nd kernel.
2315 * Since fixing handling of boot_cpu_physical_apicid requires
2316 * another discussion and tests on each platform, we leave it
2317 * for now and here we use read_apic_id() directly in this
2318 * function, generic_processor_info().
2320 if (disabled_cpu_apicid != BAD_APICID &&
2321 disabled_cpu_apicid != read_apic_id() &&
2322 disabled_cpu_apicid == apicid) {
2323 int thiscpu = num_processors + disabled_cpus;
2325 pr_warning("APIC: Disabling requested cpu."
2326 " Processor %d/0x%x ignored.\n",
2334 * If boot cpu has not been detected yet, then only allow upto
2335 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu
2337 if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
2338 apicid != boot_cpu_physical_apicid) {
2339 int thiscpu = max + disabled_cpus - 1;
2342 "APIC: NR_CPUS/possible_cpus limit of %i almost"
2343 " reached. Keeping one slot for boot cpu."
2344 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2350 if (num_processors >= nr_cpu_ids) {
2351 int thiscpu = max + disabled_cpus;
2353 pr_warning("APIC: NR_CPUS/possible_cpus limit of %i "
2354 "reached. Processor %d/0x%x ignored.\n",
2355 max, thiscpu, apicid);
2361 if (apicid == boot_cpu_physical_apicid) {
2363 * x86_bios_cpu_apicid is required to have processors listed
2364 * in same order as logical cpu numbers. Hence the first
2365 * entry is BSP, and so on.
2366 * boot_cpu_init() already hold bit 0 in cpu_present_mask
2371 /* Logical cpuid 0 is reserved for BSP. */
2372 cpuid_to_apicid[0] = apicid;
2374 cpu = allocate_logical_cpuid(apicid);
2384 if (version == 0x0) {
2385 pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
2390 if (version != boot_cpu_apic_version) {
2391 pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
2392 boot_cpu_apic_version, cpu, version);
2395 if (apicid > max_physical_apicid)
2396 max_physical_apicid = apicid;
2398 #if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2399 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2400 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
2402 #ifdef CONFIG_X86_32
2403 early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
2404 apic->x86_32_early_logical_apicid(cpu);
2406 set_cpu_possible(cpu, true);
2407 physid_set(apicid, phys_cpu_present_map);
2408 set_cpu_present(cpu, true);
2414 int hard_smp_processor_id(void)
2416 return read_apic_id();
2420 * Override the generic EOI implementation with an optimized version.
2421 * Only called during early boot when only one CPU is active and with
2422 * interrupts disabled, so we know this does not race with actual APIC driver
2425 void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
2429 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
2430 /* Should happen once for each apic */
2431 WARN_ON((*drv)->eoi_write == eoi_write);
2432 (*drv)->native_eoi_write = (*drv)->eoi_write;
2433 (*drv)->eoi_write = eoi_write;
2437 static void __init apic_bsp_up_setup(void)
2439 #ifdef CONFIG_X86_64
2440 apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid));
2443 * Hack: In case of kdump, after a crash, kernel might be booting
2444 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
2445 * might be zero if read from MP tables. Get it from LAPIC.
2447 # ifdef CONFIG_CRASH_DUMP
2448 boot_cpu_physical_apicid = read_apic_id();
2451 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
2455 * apic_bsp_setup - Setup function for local apic and io-apic
2456 * @upmode: Force UP mode (for APIC_init_uniprocessor)
2458 static void __init apic_bsp_setup(bool upmode)
2462 apic_bsp_up_setup();
2466 end_local_APIC_setup();
2467 irq_remap_enable_fault_handling();
2471 #ifdef CONFIG_UP_LATE_INIT
2472 void __init up_late_init(void)
2474 if (apic_intr_mode == APIC_PIC)
2477 /* Setup local timer */
2478 x86_init.timers.setup_percpu_clockev();
2489 * 'active' is true if the local APIC was enabled by us and
2490 * not the BIOS; this signifies that we are also responsible
2491 * for disabling it before entering apm/acpi suspend
2494 /* r/w apic fields */
2495 unsigned int apic_id;
2496 unsigned int apic_taskpri;
2497 unsigned int apic_ldr;
2498 unsigned int apic_dfr;
2499 unsigned int apic_spiv;
2500 unsigned int apic_lvtt;
2501 unsigned int apic_lvtpc;
2502 unsigned int apic_lvt0;
2503 unsigned int apic_lvt1;
2504 unsigned int apic_lvterr;
2505 unsigned int apic_tmict;
2506 unsigned int apic_tdcr;
2507 unsigned int apic_thmr;
2508 unsigned int apic_cmci;
2511 static int lapic_suspend(void)
2513 unsigned long flags;
2516 if (!apic_pm_state.active)
2519 maxlvt = lapic_get_maxlvt();
2521 apic_pm_state.apic_id = apic_read(APIC_ID);
2522 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2523 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2524 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2525 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2526 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2528 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2529 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2530 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2531 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2532 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2533 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2534 #ifdef CONFIG_X86_THERMAL_VECTOR
2536 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2538 #ifdef CONFIG_X86_MCE_INTEL
2540 apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2543 local_irq_save(flags);
2544 disable_local_APIC();
2546 irq_remapping_disable();
2548 local_irq_restore(flags);
2552 static void lapic_resume(void)
2555 unsigned long flags;
2558 if (!apic_pm_state.active)
2561 local_irq_save(flags);
2564 * IO-APIC and PIC have their own resume routines.
2565 * We just mask them here to make sure the interrupt
2566 * subsystem is completely quiet while we enable x2apic
2567 * and interrupt-remapping.
2569 mask_ioapic_entries();
2570 legacy_pic->mask_all();
2576 * Make sure the APICBASE points to the right address
2578 * FIXME! This will be wrong if we ever support suspend on
2579 * SMP! We'll need to do this as part of the CPU restore!
2581 if (boot_cpu_data.x86 >= 6) {
2582 rdmsr(MSR_IA32_APICBASE, l, h);
2583 l &= ~MSR_IA32_APICBASE_BASE;
2584 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2585 wrmsr(MSR_IA32_APICBASE, l, h);
2589 maxlvt = lapic_get_maxlvt();
2590 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2591 apic_write(APIC_ID, apic_pm_state.apic_id);
2592 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2593 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2594 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2595 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2596 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2597 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2598 #ifdef CONFIG_X86_THERMAL_VECTOR
2600 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2602 #ifdef CONFIG_X86_MCE_INTEL
2604 apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2607 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2608 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2609 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2610 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2611 apic_write(APIC_ESR, 0);
2612 apic_read(APIC_ESR);
2613 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2614 apic_write(APIC_ESR, 0);
2615 apic_read(APIC_ESR);
2617 irq_remapping_reenable(x2apic_mode);
2619 local_irq_restore(flags);
2623 * This device has no shutdown method - fully functioning local APICs
2624 * are needed on every CPU up until machine_halt/restart/poweroff.
2627 static struct syscore_ops lapic_syscore_ops = {
2628 .resume = lapic_resume,
2629 .suspend = lapic_suspend,
2632 static void apic_pm_activate(void)
2634 apic_pm_state.active = 1;
2637 static int __init init_lapic_sysfs(void)
2639 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2640 if (boot_cpu_has(X86_FEATURE_APIC))
2641 register_syscore_ops(&lapic_syscore_ops);
2646 /* local apic needs to resume before other devices access its registers. */
2647 core_initcall(init_lapic_sysfs);
2649 #else /* CONFIG_PM */
2651 static void apic_pm_activate(void) { }
2653 #endif /* CONFIG_PM */
2655 #ifdef CONFIG_X86_64
2657 static int multi_checked;
2660 static int set_multi(const struct dmi_system_id *d)
2664 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2669 static const struct dmi_system_id multi_dmi_table[] = {
2671 .callback = set_multi,
2672 .ident = "IBM System Summit2",
2674 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2675 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2681 static void dmi_check_multi(void)
2686 dmi_check_system(multi_dmi_table);
2691 * apic_is_clustered_box() -- Check if we can expect good TSC
2693 * Thus far, the major user of this is IBM's Summit2 series:
2694 * Clustered boxes may have unsynced TSC problems if they are
2696 * Use DMI to check them
2698 int apic_is_clustered_box(void)
2706 * APIC command line parameters
2708 static int __init setup_disableapic(char *arg)
2711 setup_clear_cpu_cap(X86_FEATURE_APIC);
2714 early_param("disableapic", setup_disableapic);
2716 /* same as disableapic, for compatibility */
2717 static int __init setup_nolapic(char *arg)
2719 return setup_disableapic(arg);
2721 early_param("nolapic", setup_nolapic);
2723 static int __init parse_lapic_timer_c2_ok(char *arg)
2725 local_apic_timer_c2_ok = 1;
2728 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2730 static int __init parse_disable_apic_timer(char *arg)
2732 disable_apic_timer = 1;
2735 early_param("noapictimer", parse_disable_apic_timer);
2737 static int __init parse_nolapic_timer(char *arg)
2739 disable_apic_timer = 1;
2742 early_param("nolapic_timer", parse_nolapic_timer);
2744 static int __init apic_set_verbosity(char *arg)
2747 #ifdef CONFIG_X86_64
2748 skip_ioapic_setup = 0;
2754 if (strcmp("debug", arg) == 0)
2755 apic_verbosity = APIC_DEBUG;
2756 else if (strcmp("verbose", arg) == 0)
2757 apic_verbosity = APIC_VERBOSE;
2758 #ifdef CONFIG_X86_64
2760 pr_warning("APIC Verbosity level %s not recognised"
2761 " use apic=verbose or apic=debug\n", arg);
2768 early_param("apic", apic_set_verbosity);
2770 static int __init lapic_insert_resource(void)
2775 /* Put local APIC into the resource map. */
2776 lapic_resource.start = apic_phys;
2777 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2778 insert_resource(&iomem_resource, &lapic_resource);
2784 * need call insert after e820__reserve_resources()
2785 * that is using request_resource
2787 late_initcall(lapic_insert_resource);
2789 static int __init apic_set_disabled_cpu_apicid(char *arg)
2791 if (!arg || !get_option(&arg, &disabled_cpu_apicid))
2796 early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
2798 static int __init apic_set_extnmi(char *arg)
2803 if (!strncmp("all", arg, 3))
2804 apic_extnmi = APIC_EXTNMI_ALL;
2805 else if (!strncmp("none", arg, 4))
2806 apic_extnmi = APIC_EXTNMI_NONE;
2807 else if (!strncmp("bsp", arg, 3))
2808 apic_extnmi = APIC_EXTNMI_BSP;
2810 pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2816 early_param("apic_extnmi", apic_set_extnmi);