2 * Local APIC handling, local APIC timers
4 * (c) 1999, 2000 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/init.h>
20 #include <linux/delay.h>
21 #include <linux/bootmem.h>
22 #include <linux/interrupt.h>
23 #include <linux/mc146818rtc.h>
24 #include <linux/kernel_stat.h>
25 #include <linux/sysdev.h>
26 #include <linux/ioport.h>
27 #include <linux/clockchips.h>
28 #include <linux/acpi_pmtmr.h>
29 #include <linux/module.h>
30 #include <linux/dmar.h>
32 #include <asm/atomic.h>
35 #include <asm/mpspec.h>
38 #include <asm/pgalloc.h>
41 #include <asm/proto.h>
42 #include <asm/timex.h>
44 #include <asm/i8259.h>
47 #include <mach_apic.h>
52 #if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
53 # error SPURIOUS_APIC_VECTOR definition error
56 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
57 static int disable_apic_timer __cpuinitdata;
58 static int apic_calibrate_pmtmr __initdata;
63 /* x2apic enabled before OS handover */
64 int x2apic_preenabled;
66 /* Local APIC timer works in C2 */
67 int local_apic_timer_c2_ok;
68 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
70 int first_system_vector = 0xfe;
72 char system_vectors[NR_VECTORS] = { [0 ... NR_VECTORS-1] = SYS_VECTOR_FREE};
75 * Debug level, exported for io_apic.c
77 unsigned int apic_verbosity;
81 /* Have we found an MP table */
84 static struct resource lapic_resource = {
86 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
89 static unsigned int calibration_result;
91 static int lapic_next_event(unsigned long delta,
92 struct clock_event_device *evt);
93 static void lapic_timer_setup(enum clock_event_mode mode,
94 struct clock_event_device *evt);
95 static void lapic_timer_broadcast(cpumask_t mask);
96 static void apic_pm_activate(void);
99 * The local apic timer can be used for any function which is CPU local.
101 static struct clock_event_device lapic_clockevent = {
103 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
104 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
106 .set_mode = lapic_timer_setup,
107 .set_next_event = lapic_next_event,
108 .broadcast = lapic_timer_broadcast,
112 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
114 static unsigned long apic_phys;
116 unsigned long mp_lapic_addr;
119 * Get the LAPIC version
121 static inline int lapic_get_version(void)
123 return GET_APIC_VERSION(apic_read(APIC_LVR));
127 * Check, if the APIC is integrated or a separate chip
129 static inline int lapic_is_integrated(void)
134 return APIC_INTEGRATED(lapic_get_version());
139 * Check, whether this is a modern or a first generation APIC
141 static int modern_apic(void)
143 /* AMD systems use old APIC versions, so check the CPU */
144 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
145 boot_cpu_data.x86 >= 0xf)
147 return lapic_get_version() >= 0x14;
151 * Paravirt kernels also might be using these below ops. So we still
152 * use generic apic_read()/apic_write(), which might be pointing to different
153 * ops in PARAVIRT case.
155 void xapic_wait_icr_idle(void)
157 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
161 u32 safe_xapic_wait_icr_idle(void)
168 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
172 } while (timeout++ < 1000);
177 void xapic_icr_write(u32 low, u32 id)
179 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
180 apic_write(APIC_ICR, low);
183 u64 xapic_icr_read(void)
187 icr2 = apic_read(APIC_ICR2);
188 icr1 = apic_read(APIC_ICR);
190 return icr1 | ((u64)icr2 << 32);
193 static struct apic_ops xapic_ops = {
194 .read = native_apic_mem_read,
195 .write = native_apic_mem_write,
196 .icr_read = xapic_icr_read,
197 .icr_write = xapic_icr_write,
198 .wait_icr_idle = xapic_wait_icr_idle,
199 .safe_wait_icr_idle = safe_xapic_wait_icr_idle,
202 struct apic_ops __read_mostly *apic_ops = &xapic_ops;
203 EXPORT_SYMBOL_GPL(apic_ops);
205 static void x2apic_wait_icr_idle(void)
207 /* no need to wait for icr idle in x2apic */
211 static u32 safe_x2apic_wait_icr_idle(void)
213 /* no need to wait for icr idle in x2apic */
217 void x2apic_icr_write(u32 low, u32 id)
219 wrmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), ((__u64) id) << 32 | low);
222 u64 x2apic_icr_read(void)
226 rdmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), val);
230 static struct apic_ops x2apic_ops = {
231 .read = native_apic_msr_read,
232 .write = native_apic_msr_write,
233 .icr_read = x2apic_icr_read,
234 .icr_write = x2apic_icr_write,
235 .wait_icr_idle = x2apic_wait_icr_idle,
236 .safe_wait_icr_idle = safe_x2apic_wait_icr_idle,
240 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
242 void __cpuinit enable_NMI_through_LVT0(void)
246 /* unmask and set to NMI */
249 /* Level triggered for 82489DX (32bit mode) */
250 if (!lapic_is_integrated())
251 v |= APIC_LVT_LEVEL_TRIGGER;
253 apic_write(APIC_LVT0, v);
258 * get_physical_broadcast - Get number of physical broadcast IDs
260 int get_physical_broadcast(void)
262 return modern_apic() ? 0xff : 0xf;
267 * lapic_get_maxlvt - get the maximum number of local vector table entries
269 int lapic_get_maxlvt(void)
273 v = apic_read(APIC_LVR);
275 * - we always have APIC integrated on 64bit mode
276 * - 82489DXs do not report # of LVT entries
278 return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
287 #define APIC_DIVISOR 1
289 #define APIC_DIVISOR 16
293 * This function sets up the local APIC timer, with a timeout of
294 * 'clocks' APIC bus clock. During calibration we actually call
295 * this function twice on the boot CPU, once with a bogus timeout
296 * value, second time for real. The other (noncalibrating) CPUs
297 * call this function only once, with the real, calibrated value.
299 * We do reads before writes even if unnecessary, to get around the
300 * P5 APIC double write bug.
302 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
304 unsigned int lvtt_value, tmp_value;
306 lvtt_value = LOCAL_TIMER_VECTOR;
308 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
309 if (!lapic_is_integrated())
310 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
313 lvtt_value |= APIC_LVT_MASKED;
315 apic_write(APIC_LVTT, lvtt_value);
320 tmp_value = apic_read(APIC_TDCR);
321 apic_write(APIC_TDCR,
322 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
326 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
330 * Setup extended LVT, AMD specific (K8, family 10h)
332 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
333 * MCE interrupts are supported. Thus MCE offset must be set to 0.
335 * If mask=1, the LVT entry does not generate interrupts while mask=0
336 * enables the vector. See also the BKDGs.
339 #define APIC_EILVT_LVTOFF_MCE 0
340 #define APIC_EILVT_LVTOFF_IBS 1
342 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
344 unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
345 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
350 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
352 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
353 return APIC_EILVT_LVTOFF_MCE;
356 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
358 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
359 return APIC_EILVT_LVTOFF_IBS;
361 EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
364 * Program the next event, relative to now
366 static int lapic_next_event(unsigned long delta,
367 struct clock_event_device *evt)
369 apic_write(APIC_TMICT, delta);
374 * Setup the lapic timer in periodic or oneshot mode
376 static void lapic_timer_setup(enum clock_event_mode mode,
377 struct clock_event_device *evt)
382 /* Lapic used as dummy for broadcast ? */
383 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
386 local_irq_save(flags);
389 case CLOCK_EVT_MODE_PERIODIC:
390 case CLOCK_EVT_MODE_ONESHOT:
391 __setup_APIC_LVTT(calibration_result,
392 mode != CLOCK_EVT_MODE_PERIODIC, 1);
394 case CLOCK_EVT_MODE_UNUSED:
395 case CLOCK_EVT_MODE_SHUTDOWN:
396 v = apic_read(APIC_LVTT);
397 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
398 apic_write(APIC_LVTT, v);
400 case CLOCK_EVT_MODE_RESUME:
401 /* Nothing to do here */
405 local_irq_restore(flags);
409 * Local APIC timer broadcast function
411 static void lapic_timer_broadcast(cpumask_t mask)
414 send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
419 * Setup the local APIC timer for this CPU. Copy the initilized values
420 * of the boot CPU and register the clock event in the framework.
422 static void __cpuinit setup_APIC_timer(void)
424 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
426 memcpy(levt, &lapic_clockevent, sizeof(*levt));
427 levt->cpumask = cpumask_of_cpu(smp_processor_id());
429 clockevents_register_device(levt);
433 * In this function we calibrate APIC bus clocks to the external
434 * timer. Unfortunately we cannot use jiffies and the timer irq
435 * to calibrate, since some later bootup code depends on getting
436 * the first irq? Ugh.
438 * We want to do the calibration only once since we
439 * want to have local timer irqs syncron. CPUs connected
440 * by the same APIC bus have the very same bus frequency.
441 * And we want to have irqs off anyways, no accidental
445 #define TICK_COUNT 100000000
447 static int __init calibrate_APIC_clock(void)
449 unsigned apic, apic_start;
450 unsigned long tsc, tsc_start;
456 * Put whatever arbitrary (but long enough) timeout
457 * value into the APIC clock, we just want to get the
458 * counter running for calibration.
460 * No interrupt enable !
462 __setup_APIC_LVTT(250000000, 0, 0);
464 apic_start = apic_read(APIC_TMCCT);
465 #ifdef CONFIG_X86_PM_TIMER
466 if (apic_calibrate_pmtmr && pmtmr_ioport) {
467 pmtimer_wait(5000); /* 5ms wait */
468 apic = apic_read(APIC_TMCCT);
469 result = (apic_start - apic) * 1000L / 5;
476 apic = apic_read(APIC_TMCCT);
478 } while ((tsc - tsc_start) < TICK_COUNT &&
479 (apic_start - apic) < TICK_COUNT);
481 result = (apic_start - apic) * 1000L * tsc_khz /
487 printk(KERN_DEBUG "APIC timer calibration result %d\n", result);
489 printk(KERN_INFO "Detected %d.%03d MHz APIC timer.\n",
490 result / 1000 / 1000, result / 1000 % 1000);
492 /* Calculate the scaled math multiplication factor */
493 lapic_clockevent.mult = div_sc(result, NSEC_PER_SEC,
494 lapic_clockevent.shift);
495 lapic_clockevent.max_delta_ns =
496 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
497 lapic_clockevent.min_delta_ns =
498 clockevent_delta2ns(0xF, &lapic_clockevent);
500 calibration_result = (result * APIC_DIVISOR) / HZ;
503 * Do a sanity check on the APIC calibration result
505 if (calibration_result < (1000000 / HZ)) {
507 "APIC frequency too slow, disabling apic timer\n");
515 * Setup the boot APIC
517 * Calibrate and verify the result.
519 void __init setup_boot_APIC_clock(void)
522 * The local apic timer can be disabled via the kernel
523 * commandline or from the CPU detection code. Register the lapic
524 * timer as a dummy clock event source on SMP systems, so the
525 * broadcast mechanism is used. On UP systems simply ignore it.
527 if (disable_apic_timer) {
528 printk(KERN_INFO "Disabling APIC timer\n");
529 /* No broadcast on UP ! */
530 if (num_possible_cpus() > 1) {
531 lapic_clockevent.mult = 1;
537 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
538 "calibrating APIC timer ...\n");
540 if (calibrate_APIC_clock()) {
541 /* No broadcast on UP ! */
542 if (num_possible_cpus() > 1)
548 * If nmi_watchdog is set to IO_APIC, we need the
549 * PIT/HPET going. Otherwise register lapic as a dummy
552 if (nmi_watchdog != NMI_IO_APIC)
553 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
555 printk(KERN_WARNING "APIC timer registered as dummy,"
556 " due to nmi_watchdog=%d!\n", nmi_watchdog);
558 /* Setup the lapic or request the broadcast */
562 void __cpuinit setup_secondary_APIC_clock(void)
568 * The guts of the apic timer interrupt
570 static void local_apic_timer_interrupt(void)
572 int cpu = smp_processor_id();
573 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
576 * Normally we should not be here till LAPIC has been initialized but
577 * in some cases like kdump, its possible that there is a pending LAPIC
578 * timer interrupt from previous kernel's context and is delivered in
579 * new kernel the moment interrupts are enabled.
581 * Interrupts are enabled early and LAPIC is setup much later, hence
582 * its possible that when we get here evt->event_handler is NULL.
583 * Check for event_handler being NULL and discard the interrupt as
586 if (!evt->event_handler) {
588 "Spurious LAPIC timer interrupt on cpu %d\n", cpu);
590 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
595 * the NMI deadlock-detector uses this.
598 add_pda(apic_timer_irqs, 1);
600 per_cpu(irq_stat, cpu).apic_timer_irqs++;
603 evt->event_handler(evt);
607 * Local APIC timer interrupt. This is the most natural way for doing
608 * local interrupts, but local timer interrupts can be emulated by
609 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
611 * [ if a single-CPU system runs an SMP kernel then we call the local
612 * interrupt as well. Thus we cannot inline the local irq ... ]
614 void smp_apic_timer_interrupt(struct pt_regs *regs)
616 struct pt_regs *old_regs = set_irq_regs(regs);
619 * NOTE! We'd better ACK the irq immediately,
620 * because timer handling can be slow.
624 * update_process_times() expects us to have done irq_enter().
625 * Besides, if we don't timer interrupts ignore the global
626 * interrupt lock, which is the WrongThing (tm) to do.
632 local_apic_timer_interrupt();
635 set_irq_regs(old_regs);
638 int setup_profiling_timer(unsigned int multiplier)
645 * Local APIC start and shutdown
649 * clear_local_APIC - shutdown the local APIC
651 * This is called, when a CPU is disabled and before rebooting, so the state of
652 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
653 * leftovers during boot.
655 void clear_local_APIC(void)
660 /* APIC hasn't been mapped yet */
664 maxlvt = lapic_get_maxlvt();
666 * Masking an LVT entry can trigger a local APIC error
667 * if the vector is zero. Mask LVTERR first to prevent this.
670 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
671 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
674 * Careful: we have to set masks only first to deassert
675 * any level-triggered sources.
677 v = apic_read(APIC_LVTT);
678 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
679 v = apic_read(APIC_LVT0);
680 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
681 v = apic_read(APIC_LVT1);
682 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
684 v = apic_read(APIC_LVTPC);
685 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
688 /* lets not touch this if we didn't frob it */
689 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(X86_MCE_INTEL)
691 v = apic_read(APIC_LVTTHMR);
692 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
696 * Clean APIC state for other OSs:
698 apic_write(APIC_LVTT, APIC_LVT_MASKED);
699 apic_write(APIC_LVT0, APIC_LVT_MASKED);
700 apic_write(APIC_LVT1, APIC_LVT_MASKED);
702 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
704 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
706 /* Integrated APIC (!82489DX) ? */
707 if (lapic_is_integrated()) {
709 /* Clear ESR due to Pentium errata 3AP and 11AP */
710 apic_write(APIC_ESR, 0);
716 * disable_local_APIC - clear and disable the local APIC
718 void disable_local_APIC(void)
725 * Disable APIC (implies clearing of registers
728 value = apic_read(APIC_SPIV);
729 value &= ~APIC_SPIV_APIC_ENABLED;
730 apic_write(APIC_SPIV, value);
734 * When LAPIC was disabled by the BIOS and enabled by the kernel,
735 * restore the disabled state.
737 if (enabled_via_apicbase) {
740 rdmsr(MSR_IA32_APICBASE, l, h);
741 l &= ~MSR_IA32_APICBASE_ENABLE;
742 wrmsr(MSR_IA32_APICBASE, l, h);
748 * If Linux enabled the LAPIC against the BIOS default disable it down before
749 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
750 * not power-off. Additionally clear all LVT entries before disable_local_APIC
751 * for the case where Linux didn't enable the LAPIC.
753 void lapic_shutdown(void)
760 local_irq_save(flags);
763 if (!enabled_via_apicbase)
767 disable_local_APIC();
770 local_irq_restore(flags);
774 * This is to verify that we're looking at a real local APIC.
775 * Check these against your board if the CPUs aren't getting
776 * started for no apparent reason.
778 int __init verify_local_APIC(void)
780 unsigned int reg0, reg1;
783 * The version register is read-only in a real APIC.
785 reg0 = apic_read(APIC_LVR);
786 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
787 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
788 reg1 = apic_read(APIC_LVR);
789 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
792 * The two version reads above should print the same
793 * numbers. If the second one is different, then we
794 * poke at a non-APIC.
800 * Check if the version looks reasonably.
802 reg1 = GET_APIC_VERSION(reg0);
803 if (reg1 == 0x00 || reg1 == 0xff)
805 reg1 = lapic_get_maxlvt();
806 if (reg1 < 0x02 || reg1 == 0xff)
810 * The ID register is read/write in a real APIC.
812 reg0 = apic_read(APIC_ID);
813 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
814 apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
815 reg1 = apic_read(APIC_ID);
816 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
817 apic_write(APIC_ID, reg0);
818 if (reg1 != (reg0 ^ APIC_ID_MASK))
822 * The next two are just to see if we have sane values.
823 * They're only really relevant if we're in Virtual Wire
824 * compatibility mode, but most boxes are anymore.
826 reg0 = apic_read(APIC_LVT0);
827 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
828 reg1 = apic_read(APIC_LVT1);
829 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
835 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
837 void __init sync_Arb_IDs(void)
840 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
843 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
849 apic_wait_icr_idle();
851 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
852 apic_write(APIC_ICR, APIC_DEST_ALLINC |
853 APIC_INT_LEVELTRIG | APIC_DM_INIT);
857 * An initial setup of the virtual wire mode.
859 void __init init_bsp_APIC(void)
864 * Don't do the setup now if we have a SMP BIOS as the
865 * through-I/O-APIC virtual wire mode might be active.
867 if (smp_found_config || !cpu_has_apic)
871 * Do not trust the local APIC being empty at bootup.
878 value = apic_read(APIC_SPIV);
879 value &= ~APIC_VECTOR_MASK;
880 value |= APIC_SPIV_APIC_ENABLED;
883 /* This bit is reserved on P4/Xeon and should be cleared */
884 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
885 (boot_cpu_data.x86 == 15))
886 value &= ~APIC_SPIV_FOCUS_DISABLED;
889 value |= APIC_SPIV_FOCUS_DISABLED;
890 value |= SPURIOUS_APIC_VECTOR;
891 apic_write(APIC_SPIV, value);
894 * Set up the virtual wire mode.
896 apic_write(APIC_LVT0, APIC_DM_EXTINT);
898 if (!lapic_is_integrated()) /* 82489DX */
899 value |= APIC_LVT_LEVEL_TRIGGER;
900 apic_write(APIC_LVT1, value);
903 static void __cpuinit lapic_setup_esr(void)
905 unsigned long oldvalue, value, maxlvt;
906 if (lapic_is_integrated() && !esr_disable) {
909 * Something untraceable is creating bad interrupts on
910 * secondary quads ... for the moment, just leave the
911 * ESR disabled - we can't do anything useful with the
912 * errors anyway - mbligh
914 printk(KERN_INFO "Leaving ESR disabled.\n");
918 maxlvt = lapic_get_maxlvt();
919 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
920 apic_write(APIC_ESR, 0);
921 oldvalue = apic_read(APIC_ESR);
923 /* enables sending errors */
924 value = ERROR_APIC_VECTOR;
925 apic_write(APIC_LVTERR, value);
927 * spec says clear errors after enabling vector.
930 apic_write(APIC_ESR, 0);
931 value = apic_read(APIC_ESR);
932 if (value != oldvalue)
933 apic_printk(APIC_VERBOSE, "ESR value before enabling "
934 "vector: 0x%08lx after: 0x%08lx\n",
937 printk(KERN_INFO "No ESR for 82489DX.\n");
943 * setup_local_APIC - setup the local APIC
945 void __cpuinit setup_local_APIC(void)
951 /* Pound the ESR really hard over the head with a big hammer - mbligh */
953 apic_write(APIC_ESR, 0);
954 apic_write(APIC_ESR, 0);
955 apic_write(APIC_ESR, 0);
956 apic_write(APIC_ESR, 0);
963 * Double-check whether this APIC is really registered.
964 * This is meaningless in clustered apic mode, so we skip it.
966 if (!apic_id_registered())
970 * Intel recommends to set DFR, LDR and TPR before enabling
971 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
972 * document number 292116). So here it goes...
977 * Set Task Priority to 'accept all'. We never change this
980 value = apic_read(APIC_TASKPRI);
981 value &= ~APIC_TPRI_MASK;
982 apic_write(APIC_TASKPRI, value);
985 * After a crash, we no longer service the interrupts and a pending
986 * interrupt from previous kernel might still have ISR bit set.
988 * Most probably by now CPU has serviced that pending interrupt and
989 * it might not have done the ack_APIC_irq() because it thought,
990 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
991 * does not clear the ISR bit and cpu thinks it has already serivced
992 * the interrupt. Hence a vector might get locked. It was noticed
993 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
995 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
996 value = apic_read(APIC_ISR + i*0x10);
997 for (j = 31; j >= 0; j--) {
1004 * Now that we are all set up, enable the APIC
1006 value = apic_read(APIC_SPIV);
1007 value &= ~APIC_VECTOR_MASK;
1011 value |= APIC_SPIV_APIC_ENABLED;
1013 #ifdef CONFIG_X86_32
1015 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1016 * certain networking cards. If high frequency interrupts are
1017 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1018 * entry is masked/unmasked at a high rate as well then sooner or
1019 * later IOAPIC line gets 'stuck', no more interrupts are received
1020 * from the device. If focus CPU is disabled then the hang goes
1023 * [ This bug can be reproduced easily with a level-triggered
1024 * PCI Ne2000 networking cards and PII/PIII processors, dual
1028 * Actually disabling the focus CPU check just makes the hang less
1029 * frequent as it makes the interrupt distributon model be more
1030 * like LRU than MRU (the short-term load is more even across CPUs).
1031 * See also the comment in end_level_ioapic_irq(). --macro
1035 * - enable focus processor (bit==0)
1036 * - 64bit mode always use processor focus
1037 * so no need to set it
1039 value &= ~APIC_SPIV_FOCUS_DISABLED;
1043 * Set spurious IRQ vector
1045 value |= SPURIOUS_APIC_VECTOR;
1046 apic_write(APIC_SPIV, value);
1049 * Set up LVT0, LVT1:
1051 * set up through-local-APIC on the BP's LINT0. This is not
1052 * strictly necessary in pure symmetric-IO mode, but sometimes
1053 * we delegate interrupts to the 8259A.
1056 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1058 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1059 if (!smp_processor_id() && (pic_mode || !value)) {
1060 value = APIC_DM_EXTINT;
1061 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1062 smp_processor_id());
1064 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1065 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1066 smp_processor_id());
1068 apic_write(APIC_LVT0, value);
1071 * only the BP should see the LINT1 NMI signal, obviously.
1073 if (!smp_processor_id())
1074 value = APIC_DM_NMI;
1076 value = APIC_DM_NMI | APIC_LVT_MASKED;
1077 if (!lapic_is_integrated()) /* 82489DX */
1078 value |= APIC_LVT_LEVEL_TRIGGER;
1079 apic_write(APIC_LVT1, value);
1084 void __cpuinit end_local_APIC_setup(void)
1088 #ifdef CONFIG_X86_32
1091 /* Disable the local apic timer */
1092 value = apic_read(APIC_LVTT);
1093 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1094 apic_write(APIC_LVTT, value);
1098 setup_apic_nmi_watchdog(NULL);
1102 void check_x2apic(void)
1106 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1108 if (msr & X2APIC_ENABLE) {
1109 printk("x2apic enabled by BIOS, switching to x2apic ops\n");
1110 x2apic_preenabled = x2apic = 1;
1111 apic_ops = &x2apic_ops;
1115 void enable_x2apic(void)
1119 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1120 if (!(msr & X2APIC_ENABLE)) {
1121 printk("Enabling x2apic\n");
1122 wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1126 void enable_IR_x2apic(void)
1128 #ifdef CONFIG_INTR_REMAP
1130 unsigned long flags;
1132 if (!cpu_has_x2apic)
1135 if (!x2apic_preenabled && disable_x2apic) {
1137 "Skipped enabling x2apic and Interrupt-remapping "
1138 "because of nox2apic\n");
1142 if (x2apic_preenabled && disable_x2apic)
1143 panic("Bios already enabled x2apic, can't enforce nox2apic");
1145 if (!x2apic_preenabled && skip_ioapic_setup) {
1147 "Skipped enabling x2apic and Interrupt-remapping "
1148 "because of skipping io-apic setup\n");
1152 ret = dmar_table_init();
1155 "dmar_table_init() failed with %d:\n", ret);
1157 if (x2apic_preenabled)
1158 panic("x2apic enabled by bios. But IR enabling failed");
1161 "Not enabling x2apic,Intr-remapping\n");
1165 local_irq_save(flags);
1167 save_mask_IO_APIC_setup();
1169 ret = enable_intr_remapping(1);
1171 if (ret && x2apic_preenabled) {
1172 local_irq_restore(flags);
1173 panic("x2apic enabled by bios. But IR enabling failed");
1181 apic_ops = &x2apic_ops;
1187 * IR enabling failed
1189 restore_IO_APIC_setup();
1191 reinit_intr_remapped_IO_APIC(x2apic_preenabled);
1194 local_irq_restore(flags);
1197 if (!x2apic_preenabled)
1199 "Enabled x2apic and interrupt-remapping\n");
1202 "Enabled Interrupt-remapping\n");
1205 "Failed to enable Interrupt-remapping and x2apic\n");
1207 if (!cpu_has_x2apic)
1210 if (x2apic_preenabled)
1211 panic("x2apic enabled prior OS handover,"
1212 " enable CONFIG_INTR_REMAP");
1214 printk(KERN_INFO "Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1222 * Detect and enable local APICs on non-SMP boards.
1223 * Original code written by Keir Fraser.
1224 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1225 * not correctly set up (usually the APIC timer won't work etc.)
1227 static int __init detect_init_APIC(void)
1229 if (!cpu_has_apic) {
1230 printk(KERN_INFO "No local APIC present\n");
1234 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1235 boot_cpu_physical_apicid = 0;
1239 void __init early_init_lapic_mapping(void)
1241 unsigned long phys_addr;
1244 * If no local APIC can be found then go out
1245 * : it means there is no mpatable and MADT
1247 if (!smp_found_config)
1250 phys_addr = mp_lapic_addr;
1252 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1253 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1254 APIC_BASE, phys_addr);
1257 * Fetch the APIC ID of the BSP in case we have a
1258 * default configuration (or the MP table is broken).
1260 boot_cpu_physical_apicid = read_apic_id();
1264 * init_apic_mappings - initialize APIC mappings
1266 void __init init_apic_mappings(void)
1269 boot_cpu_physical_apicid = read_apic_id();
1274 * If no local APIC can be found then set up a fake all
1275 * zeroes page to simulate the local APIC and another
1276 * one for the IO-APIC.
1278 if (!smp_found_config && detect_init_APIC()) {
1279 apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
1280 apic_phys = __pa(apic_phys);
1282 apic_phys = mp_lapic_addr;
1284 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1285 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1286 APIC_BASE, apic_phys);
1289 * Fetch the APIC ID of the BSP in case we have a
1290 * default configuration (or the MP table is broken).
1292 boot_cpu_physical_apicid = read_apic_id();
1296 * This initializes the IO-APIC and APIC hardware if this is
1299 int apic_version[MAX_APICS];
1301 int __init APIC_init_uniprocessor(void)
1304 printk(KERN_INFO "Apic disabled\n");
1307 if (!cpu_has_apic) {
1309 printk(KERN_INFO "Apic disabled by BIOS\n");
1314 setup_apic_routing();
1316 verify_local_APIC();
1320 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1321 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1326 * Now enable IO-APICs, actually call clear_IO_APIC
1327 * We need clear_IO_APIC before enabling vector on BP
1329 if (!skip_ioapic_setup && nr_ioapics)
1332 if (!smp_found_config || skip_ioapic_setup || !nr_ioapics)
1333 localise_nmi_watchdog();
1334 end_local_APIC_setup();
1336 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1340 setup_boot_APIC_clock();
1341 check_nmi_watchdog();
1346 * Local APIC interrupts
1350 * This interrupt should _never_ happen with our APIC/SMP architecture
1352 asmlinkage void smp_spurious_interrupt(void)
1358 * Check if this really is a spurious interrupt and ACK it
1359 * if it is a vectored one. Just in case...
1360 * Spurious interrupts should not be ACKed.
1362 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1363 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1366 add_pda(irq_spurious_count, 1);
1371 * This interrupt should never happen with our APIC/SMP architecture
1373 asmlinkage void smp_error_interrupt(void)
1379 /* First tickle the hardware, only then report what went on. -- REW */
1380 v = apic_read(APIC_ESR);
1381 apic_write(APIC_ESR, 0);
1382 v1 = apic_read(APIC_ESR);
1384 atomic_inc(&irq_err_count);
1386 /* Here is what the APIC error bits mean:
1389 2: Send accept error
1390 3: Receive accept error
1392 5: Send illegal vector
1393 6: Received illegal vector
1394 7: Illegal register address
1396 printk(KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
1397 smp_processor_id(), v , v1);
1402 * connect_bsp_APIC - attach the APIC to the interrupt system
1404 void __init connect_bsp_APIC(void)
1406 #ifdef CONFIG_X86_32
1409 * Do not trust the local APIC being empty at bootup.
1413 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
1414 * local APIC to INT and NMI lines.
1416 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1417 "enabling APIC mode.\n");
1426 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1427 * @virt_wire_setup: indicates, whether virtual wire mode is selected
1429 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1432 void disconnect_bsp_APIC(int virt_wire_setup)
1436 #ifdef CONFIG_X86_32
1439 * Put the board back into PIC mode (has an effect only on
1440 * certain older boards). Note that APIC interrupts, including
1441 * IPIs, won't work beyond this point! The only exception are
1444 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1445 "entering PIC mode.\n");
1452 /* Go back to Virtual Wire compatibility mode */
1454 /* For the spurious interrupt use vector F, and enable it */
1455 value = apic_read(APIC_SPIV);
1456 value &= ~APIC_VECTOR_MASK;
1457 value |= APIC_SPIV_APIC_ENABLED;
1459 apic_write(APIC_SPIV, value);
1461 if (!virt_wire_setup) {
1463 * For LVT0 make it edge triggered, active high,
1464 * external and enabled
1466 value = apic_read(APIC_LVT0);
1467 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1468 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1469 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1470 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1471 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1472 apic_write(APIC_LVT0, value);
1475 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1479 * For LVT1 make it edge triggered, active high,
1482 value = apic_read(APIC_LVT1);
1483 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1484 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1485 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1486 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1487 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1488 apic_write(APIC_LVT1, value);
1491 void __cpuinit generic_processor_info(int apicid, int version)
1499 if (version == 0x0) {
1500 printk(KERN_WARNING "BIOS bug, APIC version is 0 for CPU#%d! "
1501 "fixing up to 0x10. (tell your hw vendor)\n",
1505 apic_version[apicid] = version;
1507 if (num_processors >= NR_CPUS) {
1508 printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
1509 " Processor ignored.\n", NR_CPUS);
1514 cpus_complement(tmp_map, cpu_present_map);
1515 cpu = first_cpu(tmp_map);
1517 physid_set(apicid, phys_cpu_present_map);
1518 if (apicid == boot_cpu_physical_apicid) {
1520 * x86_bios_cpu_apicid is required to have processors listed
1521 * in same order as logical cpu numbers. Hence the first
1522 * entry is BSP, and so on.
1526 if (apicid > max_physical_apicid)
1527 max_physical_apicid = apicid;
1529 #ifdef CONFIG_X86_32
1531 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
1532 * but we need to work other dependencies like SMP_SUSPEND etc
1533 * before this can be done without some confusion.
1534 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
1535 * - Ashok Raj <ashok.raj@intel.com>
1537 if (max_physical_apicid >= 8) {
1538 switch (boot_cpu_data.x86_vendor) {
1539 case X86_VENDOR_INTEL:
1540 if (!APIC_XAPIC(version)) {
1544 /* If P4 and above fall through */
1545 case X86_VENDOR_AMD:
1551 #if defined(CONFIG_X86_SMP) || defined(CONFIG_X86_64)
1552 /* are we being called early in kernel startup? */
1553 if (early_per_cpu_ptr(x86_cpu_to_apicid)) {
1554 u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
1555 u16 *bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1557 cpu_to_apicid[cpu] = apicid;
1558 bios_cpu_apicid[cpu] = apicid;
1560 per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1561 per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1565 cpu_set(cpu, cpu_possible_map);
1566 cpu_set(cpu, cpu_present_map);
1569 int hard_smp_processor_id(void)
1571 return read_apic_id();
1581 * 'active' is true if the local APIC was enabled by us and
1582 * not the BIOS; this signifies that we are also responsible
1583 * for disabling it before entering apm/acpi suspend
1586 /* r/w apic fields */
1587 unsigned int apic_id;
1588 unsigned int apic_taskpri;
1589 unsigned int apic_ldr;
1590 unsigned int apic_dfr;
1591 unsigned int apic_spiv;
1592 unsigned int apic_lvtt;
1593 unsigned int apic_lvtpc;
1594 unsigned int apic_lvt0;
1595 unsigned int apic_lvt1;
1596 unsigned int apic_lvterr;
1597 unsigned int apic_tmict;
1598 unsigned int apic_tdcr;
1599 unsigned int apic_thmr;
1602 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1604 unsigned long flags;
1607 if (!apic_pm_state.active)
1610 maxlvt = lapic_get_maxlvt();
1612 apic_pm_state.apic_id = apic_read(APIC_ID);
1613 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1614 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1615 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1616 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1617 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1619 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1620 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1621 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1622 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1623 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1624 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1625 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1627 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1630 local_irq_save(flags);
1631 disable_local_APIC();
1632 local_irq_restore(flags);
1636 static int lapic_resume(struct sys_device *dev)
1639 unsigned long flags;
1642 if (!apic_pm_state.active)
1645 maxlvt = lapic_get_maxlvt();
1647 local_irq_save(flags);
1649 #ifdef CONFIG_X86_64
1656 * Make sure the APICBASE points to the right address
1658 * FIXME! This will be wrong if we ever support suspend on
1659 * SMP! We'll need to do this as part of the CPU restore!
1661 rdmsr(MSR_IA32_APICBASE, l, h);
1662 l &= ~MSR_IA32_APICBASE_BASE;
1663 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
1664 wrmsr(MSR_IA32_APICBASE, l, h);
1667 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
1668 apic_write(APIC_ID, apic_pm_state.apic_id);
1669 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
1670 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
1671 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
1672 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
1673 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
1674 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
1675 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1677 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
1680 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
1681 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
1682 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
1683 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
1684 apic_write(APIC_ESR, 0);
1685 apic_read(APIC_ESR);
1686 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
1687 apic_write(APIC_ESR, 0);
1688 apic_read(APIC_ESR);
1690 local_irq_restore(flags);
1696 * This device has no shutdown method - fully functioning local APICs
1697 * are needed on every CPU up until machine_halt/restart/poweroff.
1700 static struct sysdev_class lapic_sysclass = {
1702 .resume = lapic_resume,
1703 .suspend = lapic_suspend,
1706 static struct sys_device device_lapic = {
1708 .cls = &lapic_sysclass,
1711 static void __cpuinit apic_pm_activate(void)
1713 apic_pm_state.active = 1;
1716 static int __init init_lapic_sysfs(void)
1722 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
1724 error = sysdev_class_register(&lapic_sysclass);
1726 error = sysdev_register(&device_lapic);
1729 device_initcall(init_lapic_sysfs);
1731 #else /* CONFIG_PM */
1733 static void apic_pm_activate(void) { }
1735 #endif /* CONFIG_PM */
1738 * apic_is_clustered_box() -- Check if we can expect good TSC
1740 * Thus far, the major user of this is IBM's Summit2 series:
1742 * Clustered boxes may have unsynced TSC problems if they are
1743 * multi-chassis. Use available data to take a good guess.
1744 * If in doubt, go HPET.
1746 __cpuinit int apic_is_clustered_box(void)
1748 int i, clusters, zeros;
1750 u16 *bios_cpu_apicid;
1751 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
1754 * there is not this kind of box with AMD CPU yet.
1755 * Some AMD box with quadcore cpu and 8 sockets apicid
1756 * will be [4, 0x23] or [8, 0x27] could be thought to
1757 * vsmp box still need checking...
1759 if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
1762 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1763 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
1765 for (i = 0; i < NR_CPUS; i++) {
1766 /* are we being called early in kernel startup? */
1767 if (bios_cpu_apicid) {
1768 id = bios_cpu_apicid[i];
1770 else if (i < nr_cpu_ids) {
1772 id = per_cpu(x86_bios_cpu_apicid, i);
1779 if (id != BAD_APICID)
1780 __set_bit(APIC_CLUSTERID(id), clustermap);
1783 /* Problem: Partially populated chassis may not have CPUs in some of
1784 * the APIC clusters they have been allocated. Only present CPUs have
1785 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
1786 * Since clusters are allocated sequentially, count zeros only if
1787 * they are bounded by ones.
1791 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
1792 if (test_bit(i, clustermap)) {
1793 clusters += 1 + zeros;
1799 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
1800 * not guaranteed to be synced between boards
1802 if (is_vsmp_box() && clusters > 1)
1806 * If clusters > 2, then should be multi-chassis.
1807 * May have to revisit this when multi-core + hyperthreaded CPUs come
1808 * out, but AFAIK this will work even for them.
1810 return (clusters > 2);
1813 static __init int setup_nox2apic(char *str)
1816 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_X2APIC);
1819 early_param("nox2apic", setup_nox2apic);
1823 * APIC command line parameters
1825 static int __init setup_disableapic(char *arg)
1828 setup_clear_cpu_cap(X86_FEATURE_APIC);
1831 early_param("disableapic", setup_disableapic);
1833 /* same as disableapic, for compatibility */
1834 static int __init setup_nolapic(char *arg)
1836 return setup_disableapic(arg);
1838 early_param("nolapic", setup_nolapic);
1840 static int __init parse_lapic_timer_c2_ok(char *arg)
1842 local_apic_timer_c2_ok = 1;
1845 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
1847 static int __init parse_disable_apic_timer(char *arg)
1849 disable_apic_timer = 1;
1852 early_param("noapictimer", parse_disable_apic_timer);
1854 static int __init parse_nolapic_timer(char *arg)
1856 disable_apic_timer = 1;
1859 early_param("nolapic_timer", parse_nolapic_timer);
1861 #ifdef CONFIG_X86_64
1862 static __init int setup_apicpmtimer(char *s)
1864 apic_calibrate_pmtmr = 1;
1868 __setup("apicpmtimer", setup_apicpmtimer);
1871 static int __init apic_set_verbosity(char *arg)
1874 #ifdef CONFIG_X86_64
1875 skip_ioapic_setup = 0;
1881 if (strcmp("debug", arg) == 0)
1882 apic_verbosity = APIC_DEBUG;
1883 else if (strcmp("verbose", arg) == 0)
1884 apic_verbosity = APIC_VERBOSE;
1886 printk(KERN_WARNING "APIC Verbosity level %s not recognised"
1887 " use apic=verbose or apic=debug\n", arg);
1893 early_param("apic", apic_set_verbosity);
1895 static int __init lapic_insert_resource(void)
1900 /* Put local APIC into the resource map. */
1901 lapic_resource.start = apic_phys;
1902 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
1903 insert_resource(&iomem_resource, &lapic_resource);
1909 * need call insert after e820_reserve_resources()
1910 * that is using request_resource
1912 late_initcall(lapic_insert_resource);