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/cpu.h>
28 #include <linux/clockchips.h>
29 #include <linux/acpi_pmtmr.h>
30 #include <linux/module.h>
31 #include <linux/dmi.h>
32 #include <linux/dmar.h>
34 #include <asm/atomic.h>
37 #include <asm/mpspec.h>
39 #include <asm/arch_hooks.h>
41 #include <asm/pgalloc.h>
42 #include <asm/i8253.h>
45 #include <asm/proto.h>
46 #include <asm/timex.h>
48 #include <asm/i8259.h>
50 #include <mach_apic.h>
51 #include <mach_apicdef.h>
57 #if ((SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F)
58 # error SPURIOUS_APIC_VECTOR definition error
63 * Knob to control our willingness to enable the local APIC.
67 static int force_enable_local_apic;
69 * APIC command line parameters
71 static int __init parse_lapic(char *arg)
73 force_enable_local_apic = 1;
76 early_param("lapic", parse_lapic);
77 /* Local APIC was disabled by the BIOS and enabled by the kernel */
78 static int enabled_via_apicbase;
83 static int apic_calibrate_pmtmr __initdata;
84 static __init int setup_apicpmtimer(char *s)
86 apic_calibrate_pmtmr = 1;
90 __setup("apicpmtimer", setup_apicpmtimer);
99 /* x2apic enabled before OS handover */
100 int x2apic_preenabled;
102 static __init int setup_nox2apic(char *str)
105 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
108 early_param("nox2apic", setup_nox2apic);
111 unsigned long mp_lapic_addr;
113 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
114 static int disable_apic_timer __cpuinitdata;
115 /* Local APIC timer works in C2 */
116 int local_apic_timer_c2_ok;
117 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
119 int first_system_vector = 0xfe;
121 char system_vectors[NR_VECTORS] = { [0 ... NR_VECTORS-1] = SYS_VECTOR_FREE};
124 * Debug level, exported for io_apic.c
126 unsigned int apic_verbosity;
130 /* Have we found an MP table */
131 int smp_found_config;
133 static struct resource lapic_resource = {
134 .name = "Local APIC",
135 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
138 static unsigned int calibration_result;
140 static int lapic_next_event(unsigned long delta,
141 struct clock_event_device *evt);
142 static void lapic_timer_setup(enum clock_event_mode mode,
143 struct clock_event_device *evt);
144 static void lapic_timer_broadcast(cpumask_t mask);
145 static void apic_pm_activate(void);
148 * The local apic timer can be used for any function which is CPU local.
150 static struct clock_event_device lapic_clockevent = {
152 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
153 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
155 .set_mode = lapic_timer_setup,
156 .set_next_event = lapic_next_event,
157 .broadcast = lapic_timer_broadcast,
161 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
163 static unsigned long apic_phys;
166 * Get the LAPIC version
168 static inline int lapic_get_version(void)
170 return GET_APIC_VERSION(apic_read(APIC_LVR));
174 * Check, if the APIC is integrated or a separate chip
176 static inline int lapic_is_integrated(void)
181 return APIC_INTEGRATED(lapic_get_version());
186 * Check, whether this is a modern or a first generation APIC
188 static int modern_apic(void)
190 /* AMD systems use old APIC versions, so check the CPU */
191 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
192 boot_cpu_data.x86 >= 0xf)
194 return lapic_get_version() >= 0x14;
198 * Paravirt kernels also might be using these below ops. So we still
199 * use generic apic_read()/apic_write(), which might be pointing to different
200 * ops in PARAVIRT case.
202 void xapic_wait_icr_idle(void)
204 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
208 u32 safe_xapic_wait_icr_idle(void)
215 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
219 } while (timeout++ < 1000);
224 void xapic_icr_write(u32 low, u32 id)
226 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
227 apic_write(APIC_ICR, low);
230 u64 xapic_icr_read(void)
234 icr2 = apic_read(APIC_ICR2);
235 icr1 = apic_read(APIC_ICR);
237 return icr1 | ((u64)icr2 << 32);
240 static struct apic_ops xapic_ops = {
241 .read = native_apic_mem_read,
242 .write = native_apic_mem_write,
243 .icr_read = xapic_icr_read,
244 .icr_write = xapic_icr_write,
245 .wait_icr_idle = xapic_wait_icr_idle,
246 .safe_wait_icr_idle = safe_xapic_wait_icr_idle,
249 struct apic_ops __read_mostly *apic_ops = &xapic_ops;
250 EXPORT_SYMBOL_GPL(apic_ops);
253 static void x2apic_wait_icr_idle(void)
255 /* no need to wait for icr idle in x2apic */
259 static u32 safe_x2apic_wait_icr_idle(void)
261 /* no need to wait for icr idle in x2apic */
265 void x2apic_icr_write(u32 low, u32 id)
267 wrmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), ((__u64) id) << 32 | low);
270 u64 x2apic_icr_read(void)
274 rdmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), val);
278 static struct apic_ops x2apic_ops = {
279 .read = native_apic_msr_read,
280 .write = native_apic_msr_write,
281 .icr_read = x2apic_icr_read,
282 .icr_write = x2apic_icr_write,
283 .wait_icr_idle = x2apic_wait_icr_idle,
284 .safe_wait_icr_idle = safe_x2apic_wait_icr_idle,
289 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
291 void __cpuinit enable_NMI_through_LVT0(void)
295 /* unmask and set to NMI */
298 /* Level triggered for 82489DX (32bit mode) */
299 if (!lapic_is_integrated())
300 v |= APIC_LVT_LEVEL_TRIGGER;
302 apic_write(APIC_LVT0, v);
307 * get_physical_broadcast - Get number of physical broadcast IDs
309 int get_physical_broadcast(void)
311 return modern_apic() ? 0xff : 0xf;
316 * lapic_get_maxlvt - get the maximum number of local vector table entries
318 int lapic_get_maxlvt(void)
322 v = apic_read(APIC_LVR);
324 * - we always have APIC integrated on 64bit mode
325 * - 82489DXs do not report # of LVT entries
327 return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
335 #define APIC_DIVISOR 16
338 * This function sets up the local APIC timer, with a timeout of
339 * 'clocks' APIC bus clock. During calibration we actually call
340 * this function twice on the boot CPU, once with a bogus timeout
341 * value, second time for real. The other (noncalibrating) CPUs
342 * call this function only once, with the real, calibrated value.
344 * We do reads before writes even if unnecessary, to get around the
345 * P5 APIC double write bug.
347 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
349 unsigned int lvtt_value, tmp_value;
351 lvtt_value = LOCAL_TIMER_VECTOR;
353 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
354 if (!lapic_is_integrated())
355 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
358 lvtt_value |= APIC_LVT_MASKED;
360 apic_write(APIC_LVTT, lvtt_value);
365 tmp_value = apic_read(APIC_TDCR);
366 apic_write(APIC_TDCR,
367 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
371 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
375 * Setup extended LVT, AMD specific (K8, family 10h)
377 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
378 * MCE interrupts are supported. Thus MCE offset must be set to 0.
380 * If mask=1, the LVT entry does not generate interrupts while mask=0
381 * enables the vector. See also the BKDGs.
384 #define APIC_EILVT_LVTOFF_MCE 0
385 #define APIC_EILVT_LVTOFF_IBS 1
387 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
389 unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
390 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
395 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
397 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
398 return APIC_EILVT_LVTOFF_MCE;
401 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
403 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
404 return APIC_EILVT_LVTOFF_IBS;
406 EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
409 * Program the next event, relative to now
411 static int lapic_next_event(unsigned long delta,
412 struct clock_event_device *evt)
414 apic_write(APIC_TMICT, delta);
419 * Setup the lapic timer in periodic or oneshot mode
421 static void lapic_timer_setup(enum clock_event_mode mode,
422 struct clock_event_device *evt)
427 /* Lapic used as dummy for broadcast ? */
428 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
431 local_irq_save(flags);
434 case CLOCK_EVT_MODE_PERIODIC:
435 case CLOCK_EVT_MODE_ONESHOT:
436 __setup_APIC_LVTT(calibration_result,
437 mode != CLOCK_EVT_MODE_PERIODIC, 1);
439 case CLOCK_EVT_MODE_UNUSED:
440 case CLOCK_EVT_MODE_SHUTDOWN:
441 v = apic_read(APIC_LVTT);
442 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
443 apic_write(APIC_LVTT, v);
445 case CLOCK_EVT_MODE_RESUME:
446 /* Nothing to do here */
450 local_irq_restore(flags);
454 * Local APIC timer broadcast function
456 static void lapic_timer_broadcast(cpumask_t mask)
459 send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
464 * Setup the local APIC timer for this CPU. Copy the initilized values
465 * of the boot CPU and register the clock event in the framework.
467 static void __cpuinit setup_APIC_timer(void)
469 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
471 memcpy(levt, &lapic_clockevent, sizeof(*levt));
472 levt->cpumask = cpumask_of_cpu(smp_processor_id());
474 clockevents_register_device(levt);
478 * In this functions we calibrate APIC bus clocks to the external timer.
480 * We want to do the calibration only once since we want to have local timer
481 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
484 * This was previously done by reading the PIT/HPET and waiting for a wrap
485 * around to find out, that a tick has elapsed. I have a box, where the PIT
486 * readout is broken, so it never gets out of the wait loop again. This was
487 * also reported by others.
489 * Monitoring the jiffies value is inaccurate and the clockevents
490 * infrastructure allows us to do a simple substitution of the interrupt
493 * The calibration routine also uses the pm_timer when possible, as the PIT
494 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
495 * back to normal later in the boot process).
498 #define LAPIC_CAL_LOOPS (HZ/10)
500 static __initdata int lapic_cal_loops = -1;
501 static __initdata long lapic_cal_t1, lapic_cal_t2;
502 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
503 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
504 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
507 * Temporary interrupt handler.
509 static void __init lapic_cal_handler(struct clock_event_device *dev)
511 unsigned long long tsc = 0;
512 long tapic = apic_read(APIC_TMCCT);
513 unsigned long pm = acpi_pm_read_early();
518 switch (lapic_cal_loops++) {
520 lapic_cal_t1 = tapic;
521 lapic_cal_tsc1 = tsc;
523 lapic_cal_j1 = jiffies;
526 case LAPIC_CAL_LOOPS:
527 lapic_cal_t2 = tapic;
528 lapic_cal_tsc2 = tsc;
529 if (pm < lapic_cal_pm1)
530 pm += ACPI_PM_OVRRUN;
532 lapic_cal_j2 = jiffies;
537 static int __init calibrate_by_pmtimer(long deltapm, long *delta)
539 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
540 const long pm_thresh = pm_100ms / 100;
544 #ifndef CONFIG_X86_PM_TIMER
548 apic_printk(APIC_VERBOSE, "... PM timer delta = %ld\n", deltapm);
550 /* Check, if the PM timer is available */
554 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
556 if (deltapm > (pm_100ms - pm_thresh) &&
557 deltapm < (pm_100ms + pm_thresh)) {
558 apic_printk(APIC_VERBOSE, "... PM timer result ok\n");
560 res = (((u64)deltapm) * mult) >> 22;
561 do_div(res, 1000000);
562 printk(KERN_WARNING "APIC calibration not consistent "
563 "with PM Timer: %ldms instead of 100ms\n",
565 /* Correct the lapic counter value */
566 res = (((u64)(*delta)) * pm_100ms);
567 do_div(res, deltapm);
568 printk(KERN_INFO "APIC delta adjusted to PM-Timer: "
569 "%lu (%ld)\n", (unsigned long)res, *delta);
576 static int __init calibrate_APIC_clock(void)
578 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
579 void (*real_handler)(struct clock_event_device *dev);
580 unsigned long deltaj;
582 int pm_referenced = 0;
586 /* Replace the global interrupt handler */
587 real_handler = global_clock_event->event_handler;
588 global_clock_event->event_handler = lapic_cal_handler;
591 * Setup the APIC counter to maximum. There is no way the lapic
592 * can underflow in the 100ms detection time frame
594 __setup_APIC_LVTT(0xffffffff, 0, 0);
596 /* Let the interrupts run */
599 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
604 /* Restore the real event handler */
605 global_clock_event->event_handler = real_handler;
607 /* Build delta t1-t2 as apic timer counts down */
608 delta = lapic_cal_t1 - lapic_cal_t2;
609 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
611 /* we trust the PM based calibration if possible */
612 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
615 /* Calculate the scaled math multiplication factor */
616 lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
617 lapic_clockevent.shift);
618 lapic_clockevent.max_delta_ns =
619 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
620 lapic_clockevent.min_delta_ns =
621 clockevent_delta2ns(0xF, &lapic_clockevent);
623 calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
625 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
626 apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
627 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
631 delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
632 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
634 (delta / LAPIC_CAL_LOOPS) / (1000000 / HZ),
635 (delta / LAPIC_CAL_LOOPS) % (1000000 / HZ));
638 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
640 calibration_result / (1000000 / HZ),
641 calibration_result % (1000000 / HZ));
644 * Do a sanity check on the APIC calibration result
646 if (calibration_result < (1000000 / HZ)) {
649 "APIC frequency too slow, disabling apic timer\n");
653 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
656 * PM timer calibration failed or not turned on
657 * so lets try APIC timer based calibration
659 if (!pm_referenced) {
660 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
663 * Setup the apic timer manually
665 levt->event_handler = lapic_cal_handler;
666 lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
667 lapic_cal_loops = -1;
669 /* Let the interrupts run */
672 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
677 /* Stop the lapic timer */
678 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
683 deltaj = lapic_cal_j2 - lapic_cal_j1;
684 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
686 /* Check, if the jiffies result is consistent */
687 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
688 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
690 levt->features |= CLOCK_EVT_FEAT_DUMMY;
694 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
696 "APIC timer disabled due to verification failure.\n");
704 * Setup the boot APIC
706 * Calibrate and verify the result.
708 void __init setup_boot_APIC_clock(void)
711 * The local apic timer can be disabled via the kernel
712 * commandline or from the CPU detection code. Register the lapic
713 * timer as a dummy clock event source on SMP systems, so the
714 * broadcast mechanism is used. On UP systems simply ignore it.
716 if (disable_apic_timer) {
717 printk(KERN_INFO "Disabling APIC timer\n");
718 /* No broadcast on UP ! */
719 if (num_possible_cpus() > 1) {
720 lapic_clockevent.mult = 1;
726 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
727 "calibrating APIC timer ...\n");
729 if (calibrate_APIC_clock()) {
730 /* No broadcast on UP ! */
731 if (num_possible_cpus() > 1)
737 * If nmi_watchdog is set to IO_APIC, we need the
738 * PIT/HPET going. Otherwise register lapic as a dummy
741 if (nmi_watchdog != NMI_IO_APIC)
742 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
744 printk(KERN_WARNING "APIC timer registered as dummy,"
745 " due to nmi_watchdog=%d!\n", nmi_watchdog);
747 /* Setup the lapic or request the broadcast */
751 void __cpuinit setup_secondary_APIC_clock(void)
757 * The guts of the apic timer interrupt
759 static void local_apic_timer_interrupt(void)
761 int cpu = smp_processor_id();
762 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
765 * Normally we should not be here till LAPIC has been initialized but
766 * in some cases like kdump, its possible that there is a pending LAPIC
767 * timer interrupt from previous kernel's context and is delivered in
768 * new kernel the moment interrupts are enabled.
770 * Interrupts are enabled early and LAPIC is setup much later, hence
771 * its possible that when we get here evt->event_handler is NULL.
772 * Check for event_handler being NULL and discard the interrupt as
775 if (!evt->event_handler) {
777 "Spurious LAPIC timer interrupt on cpu %d\n", cpu);
779 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
784 * the NMI deadlock-detector uses this.
787 add_pda(apic_timer_irqs, 1);
789 per_cpu(irq_stat, cpu).apic_timer_irqs++;
792 evt->event_handler(evt);
796 * Local APIC timer interrupt. This is the most natural way for doing
797 * local interrupts, but local timer interrupts can be emulated by
798 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
800 * [ if a single-CPU system runs an SMP kernel then we call the local
801 * interrupt as well. Thus we cannot inline the local irq ... ]
803 void smp_apic_timer_interrupt(struct pt_regs *regs)
805 struct pt_regs *old_regs = set_irq_regs(regs);
808 * NOTE! We'd better ACK the irq immediately,
809 * because timer handling can be slow.
813 * update_process_times() expects us to have done irq_enter().
814 * Besides, if we don't timer interrupts ignore the global
815 * interrupt lock, which is the WrongThing (tm) to do.
819 local_apic_timer_interrupt();
822 set_irq_regs(old_regs);
825 int setup_profiling_timer(unsigned int multiplier)
831 * Local APIC start and shutdown
835 * clear_local_APIC - shutdown the local APIC
837 * This is called, when a CPU is disabled and before rebooting, so the state of
838 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
839 * leftovers during boot.
841 void clear_local_APIC(void)
846 /* APIC hasn't been mapped yet */
850 maxlvt = lapic_get_maxlvt();
852 * Masking an LVT entry can trigger a local APIC error
853 * if the vector is zero. Mask LVTERR first to prevent this.
856 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
857 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
860 * Careful: we have to set masks only first to deassert
861 * any level-triggered sources.
863 v = apic_read(APIC_LVTT);
864 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
865 v = apic_read(APIC_LVT0);
866 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
867 v = apic_read(APIC_LVT1);
868 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
870 v = apic_read(APIC_LVTPC);
871 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
874 /* lets not touch this if we didn't frob it */
875 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(X86_MCE_INTEL)
877 v = apic_read(APIC_LVTTHMR);
878 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
882 * Clean APIC state for other OSs:
884 apic_write(APIC_LVTT, APIC_LVT_MASKED);
885 apic_write(APIC_LVT0, APIC_LVT_MASKED);
886 apic_write(APIC_LVT1, APIC_LVT_MASKED);
888 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
890 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
892 /* Integrated APIC (!82489DX) ? */
893 if (lapic_is_integrated()) {
895 /* Clear ESR due to Pentium errata 3AP and 11AP */
896 apic_write(APIC_ESR, 0);
902 * disable_local_APIC - clear and disable the local APIC
904 void disable_local_APIC(void)
911 * Disable APIC (implies clearing of registers
914 value = apic_read(APIC_SPIV);
915 value &= ~APIC_SPIV_APIC_ENABLED;
916 apic_write(APIC_SPIV, value);
920 * When LAPIC was disabled by the BIOS and enabled by the kernel,
921 * restore the disabled state.
923 if (enabled_via_apicbase) {
926 rdmsr(MSR_IA32_APICBASE, l, h);
927 l &= ~MSR_IA32_APICBASE_ENABLE;
928 wrmsr(MSR_IA32_APICBASE, l, h);
934 * If Linux enabled the LAPIC against the BIOS default disable it down before
935 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
936 * not power-off. Additionally clear all LVT entries before disable_local_APIC
937 * for the case where Linux didn't enable the LAPIC.
939 void lapic_shutdown(void)
946 local_irq_save(flags);
949 if (!enabled_via_apicbase)
953 disable_local_APIC();
956 local_irq_restore(flags);
960 * This is to verify that we're looking at a real local APIC.
961 * Check these against your board if the CPUs aren't getting
962 * started for no apparent reason.
964 int __init verify_local_APIC(void)
966 unsigned int reg0, reg1;
969 * The version register is read-only in a real APIC.
971 reg0 = apic_read(APIC_LVR);
972 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
973 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
974 reg1 = apic_read(APIC_LVR);
975 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
978 * The two version reads above should print the same
979 * numbers. If the second one is different, then we
980 * poke at a non-APIC.
986 * Check if the version looks reasonably.
988 reg1 = GET_APIC_VERSION(reg0);
989 if (reg1 == 0x00 || reg1 == 0xff)
991 reg1 = lapic_get_maxlvt();
992 if (reg1 < 0x02 || reg1 == 0xff)
996 * The ID register is read/write in a real APIC.
998 reg0 = apic_read(APIC_ID);
999 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
1000 apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
1001 reg1 = apic_read(APIC_ID);
1002 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
1003 apic_write(APIC_ID, reg0);
1004 if (reg1 != (reg0 ^ APIC_ID_MASK))
1008 * The next two are just to see if we have sane values.
1009 * They're only really relevant if we're in Virtual Wire
1010 * compatibility mode, but most boxes are anymore.
1012 reg0 = apic_read(APIC_LVT0);
1013 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
1014 reg1 = apic_read(APIC_LVT1);
1015 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
1021 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1023 void __init sync_Arb_IDs(void)
1026 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1029 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1035 apic_wait_icr_idle();
1037 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1038 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1039 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1043 * An initial setup of the virtual wire mode.
1045 void __init init_bsp_APIC(void)
1050 * Don't do the setup now if we have a SMP BIOS as the
1051 * through-I/O-APIC virtual wire mode might be active.
1053 if (smp_found_config || !cpu_has_apic)
1057 * Do not trust the local APIC being empty at bootup.
1064 value = apic_read(APIC_SPIV);
1065 value &= ~APIC_VECTOR_MASK;
1066 value |= APIC_SPIV_APIC_ENABLED;
1068 #ifdef CONFIG_X86_32
1069 /* This bit is reserved on P4/Xeon and should be cleared */
1070 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1071 (boot_cpu_data.x86 == 15))
1072 value &= ~APIC_SPIV_FOCUS_DISABLED;
1075 value |= APIC_SPIV_FOCUS_DISABLED;
1076 value |= SPURIOUS_APIC_VECTOR;
1077 apic_write(APIC_SPIV, value);
1080 * Set up the virtual wire mode.
1082 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1083 value = APIC_DM_NMI;
1084 if (!lapic_is_integrated()) /* 82489DX */
1085 value |= APIC_LVT_LEVEL_TRIGGER;
1086 apic_write(APIC_LVT1, value);
1089 static void __cpuinit lapic_setup_esr(void)
1091 unsigned int oldvalue, value, maxlvt;
1093 if (!lapic_is_integrated()) {
1094 printk(KERN_INFO "No ESR for 82489DX.\n");
1100 * Something untraceable is creating bad interrupts on
1101 * secondary quads ... for the moment, just leave the
1102 * ESR disabled - we can't do anything useful with the
1103 * errors anyway - mbligh
1105 printk(KERN_INFO "Leaving ESR disabled.\n");
1109 maxlvt = lapic_get_maxlvt();
1110 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1111 apic_write(APIC_ESR, 0);
1112 oldvalue = apic_read(APIC_ESR);
1114 /* enables sending errors */
1115 value = ERROR_APIC_VECTOR;
1116 apic_write(APIC_LVTERR, value);
1119 * spec says clear errors after enabling vector.
1122 apic_write(APIC_ESR, 0);
1123 value = apic_read(APIC_ESR);
1124 if (value != oldvalue)
1125 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1126 "vector: 0x%08x after: 0x%08x\n",
1132 * setup_local_APIC - setup the local APIC
1134 void __cpuinit setup_local_APIC(void)
1139 #ifdef CONFIG_X86_32
1140 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1141 if (lapic_is_integrated() && esr_disable) {
1142 apic_write(APIC_ESR, 0);
1143 apic_write(APIC_ESR, 0);
1144 apic_write(APIC_ESR, 0);
1145 apic_write(APIC_ESR, 0);
1152 * Double-check whether this APIC is really registered.
1153 * This is meaningless in clustered apic mode, so we skip it.
1155 if (!apic_id_registered())
1159 * Intel recommends to set DFR, LDR and TPR before enabling
1160 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1161 * document number 292116). So here it goes...
1166 * Set Task Priority to 'accept all'. We never change this
1169 value = apic_read(APIC_TASKPRI);
1170 value &= ~APIC_TPRI_MASK;
1171 apic_write(APIC_TASKPRI, value);
1174 * After a crash, we no longer service the interrupts and a pending
1175 * interrupt from previous kernel might still have ISR bit set.
1177 * Most probably by now CPU has serviced that pending interrupt and
1178 * it might not have done the ack_APIC_irq() because it thought,
1179 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1180 * does not clear the ISR bit and cpu thinks it has already serivced
1181 * the interrupt. Hence a vector might get locked. It was noticed
1182 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1184 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1185 value = apic_read(APIC_ISR + i*0x10);
1186 for (j = 31; j >= 0; j--) {
1193 * Now that we are all set up, enable the APIC
1195 value = apic_read(APIC_SPIV);
1196 value &= ~APIC_VECTOR_MASK;
1200 value |= APIC_SPIV_APIC_ENABLED;
1202 #ifdef CONFIG_X86_32
1204 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1205 * certain networking cards. If high frequency interrupts are
1206 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1207 * entry is masked/unmasked at a high rate as well then sooner or
1208 * later IOAPIC line gets 'stuck', no more interrupts are received
1209 * from the device. If focus CPU is disabled then the hang goes
1212 * [ This bug can be reproduced easily with a level-triggered
1213 * PCI Ne2000 networking cards and PII/PIII processors, dual
1217 * Actually disabling the focus CPU check just makes the hang less
1218 * frequent as it makes the interrupt distributon model be more
1219 * like LRU than MRU (the short-term load is more even across CPUs).
1220 * See also the comment in end_level_ioapic_irq(). --macro
1224 * - enable focus processor (bit==0)
1225 * - 64bit mode always use processor focus
1226 * so no need to set it
1228 value &= ~APIC_SPIV_FOCUS_DISABLED;
1232 * Set spurious IRQ vector
1234 value |= SPURIOUS_APIC_VECTOR;
1235 apic_write(APIC_SPIV, value);
1238 * Set up LVT0, LVT1:
1240 * set up through-local-APIC on the BP's LINT0. This is not
1241 * strictly necessary in pure symmetric-IO mode, but sometimes
1242 * we delegate interrupts to the 8259A.
1245 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1247 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1248 if (!smp_processor_id() && (pic_mode || !value)) {
1249 value = APIC_DM_EXTINT;
1250 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
1251 smp_processor_id());
1253 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1254 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
1255 smp_processor_id());
1257 apic_write(APIC_LVT0, value);
1260 * only the BP should see the LINT1 NMI signal, obviously.
1262 if (!smp_processor_id())
1263 value = APIC_DM_NMI;
1265 value = APIC_DM_NMI | APIC_LVT_MASKED;
1266 if (!lapic_is_integrated()) /* 82489DX */
1267 value |= APIC_LVT_LEVEL_TRIGGER;
1268 apic_write(APIC_LVT1, value);
1273 void __cpuinit end_local_APIC_setup(void)
1277 #ifdef CONFIG_X86_32
1280 /* Disable the local apic timer */
1281 value = apic_read(APIC_LVTT);
1282 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1283 apic_write(APIC_LVTT, value);
1287 setup_apic_nmi_watchdog(NULL);
1292 void check_x2apic(void)
1296 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1298 if (msr & X2APIC_ENABLE) {
1299 printk("x2apic enabled by BIOS, switching to x2apic ops\n");
1300 x2apic_preenabled = x2apic = 1;
1301 apic_ops = &x2apic_ops;
1305 void enable_x2apic(void)
1309 rdmsr(MSR_IA32_APICBASE, msr, msr2);
1310 if (!(msr & X2APIC_ENABLE)) {
1311 printk("Enabling x2apic\n");
1312 wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
1316 void __init enable_IR_x2apic(void)
1318 #ifdef CONFIG_INTR_REMAP
1320 unsigned long flags;
1322 if (!cpu_has_x2apic)
1325 if (!x2apic_preenabled && disable_x2apic) {
1327 "Skipped enabling x2apic and Interrupt-remapping "
1328 "because of nox2apic\n");
1332 if (x2apic_preenabled && disable_x2apic)
1333 panic("Bios already enabled x2apic, can't enforce nox2apic");
1335 if (!x2apic_preenabled && skip_ioapic_setup) {
1337 "Skipped enabling x2apic and Interrupt-remapping "
1338 "because of skipping io-apic setup\n");
1342 ret = dmar_table_init();
1345 "dmar_table_init() failed with %d:\n", ret);
1347 if (x2apic_preenabled)
1348 panic("x2apic enabled by bios. But IR enabling failed");
1351 "Not enabling x2apic,Intr-remapping\n");
1355 local_irq_save(flags);
1358 ret = save_mask_IO_APIC_setup();
1360 printk(KERN_INFO "Saving IO-APIC state failed: %d\n", ret);
1364 ret = enable_intr_remapping(1);
1366 if (ret && x2apic_preenabled) {
1367 local_irq_restore(flags);
1368 panic("x2apic enabled by bios. But IR enabling failed");
1376 apic_ops = &x2apic_ops;
1383 * IR enabling failed
1385 restore_IO_APIC_setup();
1387 reinit_intr_remapped_IO_APIC(x2apic_preenabled);
1391 local_irq_restore(flags);
1394 if (!x2apic_preenabled)
1396 "Enabled x2apic and interrupt-remapping\n");
1399 "Enabled Interrupt-remapping\n");
1402 "Failed to enable Interrupt-remapping and x2apic\n");
1404 if (!cpu_has_x2apic)
1407 if (x2apic_preenabled)
1408 panic("x2apic enabled prior OS handover,"
1409 " enable CONFIG_INTR_REMAP");
1411 printk(KERN_INFO "Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1417 #endif /* HAVE_X2APIC */
1419 #ifdef CONFIG_X86_64
1421 * Detect and enable local APICs on non-SMP boards.
1422 * Original code written by Keir Fraser.
1423 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1424 * not correctly set up (usually the APIC timer won't work etc.)
1426 static int __init detect_init_APIC(void)
1428 if (!cpu_has_apic) {
1429 printk(KERN_INFO "No local APIC present\n");
1433 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1434 boot_cpu_physical_apicid = 0;
1439 * Detect and initialize APIC
1441 static int __init detect_init_APIC(void)
1445 /* Disabled by kernel option? */
1449 switch (boot_cpu_data.x86_vendor) {
1450 case X86_VENDOR_AMD:
1451 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1452 (boot_cpu_data.x86 == 15))
1455 case X86_VENDOR_INTEL:
1456 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1457 (boot_cpu_data.x86 == 5 && cpu_has_apic))
1464 if (!cpu_has_apic) {
1466 * Over-ride BIOS and try to enable the local APIC only if
1467 * "lapic" specified.
1469 if (!force_enable_local_apic) {
1470 printk(KERN_INFO "Local APIC disabled by BIOS -- "
1471 "you can enable it with \"lapic\"\n");
1475 * Some BIOSes disable the local APIC in the APIC_BASE
1476 * MSR. This can only be done in software for Intel P6 or later
1477 * and AMD K7 (Model > 1) or later.
1479 rdmsr(MSR_IA32_APICBASE, l, h);
1480 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1482 "Local APIC disabled by BIOS -- reenabling.\n");
1483 l &= ~MSR_IA32_APICBASE_BASE;
1484 l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
1485 wrmsr(MSR_IA32_APICBASE, l, h);
1486 enabled_via_apicbase = 1;
1490 * The APIC feature bit should now be enabled
1493 features = cpuid_edx(1);
1494 if (!(features & (1 << X86_FEATURE_APIC))) {
1495 printk(KERN_WARNING "Could not enable APIC!\n");
1498 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1499 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1501 /* The BIOS may have set up the APIC at some other address */
1502 rdmsr(MSR_IA32_APICBASE, l, h);
1503 if (l & MSR_IA32_APICBASE_ENABLE)
1504 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1506 printk(KERN_INFO "Found and enabled local APIC!\n");
1513 printk(KERN_INFO "No local APIC present or hardware disabled\n");
1518 #ifdef CONFIG_X86_64
1519 void __init early_init_lapic_mapping(void)
1521 unsigned long phys_addr;
1524 * If no local APIC can be found then go out
1525 * : it means there is no mpatable and MADT
1527 if (!smp_found_config)
1530 phys_addr = mp_lapic_addr;
1532 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1533 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1534 APIC_BASE, phys_addr);
1537 * Fetch the APIC ID of the BSP in case we have a
1538 * default configuration (or the MP table is broken).
1540 boot_cpu_physical_apicid = read_apic_id();
1545 * init_apic_mappings - initialize APIC mappings
1547 void __init init_apic_mappings(void)
1551 boot_cpu_physical_apicid = read_apic_id();
1557 * If no local APIC can be found then set up a fake all
1558 * zeroes page to simulate the local APIC and another
1559 * one for the IO-APIC.
1561 if (!smp_found_config && detect_init_APIC()) {
1562 apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
1563 apic_phys = __pa(apic_phys);
1565 apic_phys = mp_lapic_addr;
1567 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1568 apic_printk(APIC_VERBOSE, "mapped APIC to %08lx (%08lx)\n",
1569 APIC_BASE, apic_phys);
1572 * Fetch the APIC ID of the BSP in case we have a
1573 * default configuration (or the MP table is broken).
1575 if (boot_cpu_physical_apicid == -1U)
1576 boot_cpu_physical_apicid = read_apic_id();
1580 * This initializes the IO-APIC and APIC hardware if this is
1583 int apic_version[MAX_APICS];
1585 int __init APIC_init_uniprocessor(void)
1587 #ifdef CONFIG_X86_64
1589 printk(KERN_INFO "Apic disabled\n");
1592 if (!cpu_has_apic) {
1594 printk(KERN_INFO "Apic disabled by BIOS\n");
1598 if (!smp_found_config && !cpu_has_apic)
1602 * Complain if the BIOS pretends there is one.
1604 if (!cpu_has_apic &&
1605 APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1606 printk(KERN_ERR "BIOS bug, local APIC 0x%x not detected!...\n",
1607 boot_cpu_physical_apicid);
1608 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1616 #ifdef CONFIG_X86_64
1617 setup_apic_routing();
1620 verify_local_APIC();
1623 #ifdef CONFIG_X86_64
1624 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1627 * Hack: In case of kdump, after a crash, kernel might be booting
1628 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1629 * might be zero if read from MP tables. Get it from LAPIC.
1631 # ifdef CONFIG_CRASH_DUMP
1632 boot_cpu_physical_apicid = read_apic_id();
1635 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1638 #ifdef CONFIG_X86_64
1640 * Now enable IO-APICs, actually call clear_IO_APIC
1641 * We need clear_IO_APIC before enabling vector on BP
1643 if (!skip_ioapic_setup && nr_ioapics)
1647 #ifdef CONFIG_X86_IO_APIC
1648 if (!smp_found_config || skip_ioapic_setup || !nr_ioapics)
1650 localise_nmi_watchdog();
1651 end_local_APIC_setup();
1653 #ifdef CONFIG_X86_IO_APIC
1654 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1656 # ifdef CONFIG_X86_64
1662 #ifdef CONFIG_X86_64
1663 setup_boot_APIC_clock();
1664 check_nmi_watchdog();
1673 * Local APIC interrupts
1677 * This interrupt should _never_ happen with our APIC/SMP architecture
1679 void smp_spurious_interrupt(struct pt_regs *regs)
1686 * Check if this really is a spurious interrupt and ACK it
1687 * if it is a vectored one. Just in case...
1688 * Spurious interrupts should not be ACKed.
1690 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1691 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1694 #ifdef CONFIG_X86_64
1695 add_pda(irq_spurious_count, 1);
1697 /* see sw-dev-man vol 3, chapter 7.4.13.5 */
1698 printk(KERN_INFO "spurious APIC interrupt on CPU#%d, "
1699 "should never happen.\n", smp_processor_id());
1700 __get_cpu_var(irq_stat).irq_spurious_count++;
1706 * This interrupt should never happen with our APIC/SMP architecture
1708 void smp_error_interrupt(struct pt_regs *regs)
1714 /* First tickle the hardware, only then report what went on. -- REW */
1715 v = apic_read(APIC_ESR);
1716 apic_write(APIC_ESR, 0);
1717 v1 = apic_read(APIC_ESR);
1719 atomic_inc(&irq_err_count);
1721 /* Here is what the APIC error bits mean:
1724 2: Send accept error
1725 3: Receive accept error
1727 5: Send illegal vector
1728 6: Received illegal vector
1729 7: Illegal register address
1731 printk(KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
1732 smp_processor_id(), v , v1);
1737 * connect_bsp_APIC - attach the APIC to the interrupt system
1739 void __init connect_bsp_APIC(void)
1741 #ifdef CONFIG_X86_32
1744 * Do not trust the local APIC being empty at bootup.
1748 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
1749 * local APIC to INT and NMI lines.
1751 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1752 "enabling APIC mode.\n");
1761 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1762 * @virt_wire_setup: indicates, whether virtual wire mode is selected
1764 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1767 void disconnect_bsp_APIC(int virt_wire_setup)
1771 #ifdef CONFIG_X86_32
1774 * Put the board back into PIC mode (has an effect only on
1775 * certain older boards). Note that APIC interrupts, including
1776 * IPIs, won't work beyond this point! The only exception are
1779 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1780 "entering PIC mode.\n");
1787 /* Go back to Virtual Wire compatibility mode */
1789 /* For the spurious interrupt use vector F, and enable it */
1790 value = apic_read(APIC_SPIV);
1791 value &= ~APIC_VECTOR_MASK;
1792 value |= APIC_SPIV_APIC_ENABLED;
1794 apic_write(APIC_SPIV, value);
1796 if (!virt_wire_setup) {
1798 * For LVT0 make it edge triggered, active high,
1799 * external and enabled
1801 value = apic_read(APIC_LVT0);
1802 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1803 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1804 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1805 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1806 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1807 apic_write(APIC_LVT0, value);
1810 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1814 * For LVT1 make it edge triggered, active high,
1817 value = apic_read(APIC_LVT1);
1818 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1819 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1820 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1821 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1822 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1823 apic_write(APIC_LVT1, value);
1826 void __cpuinit generic_processor_info(int apicid, int version)
1834 if (version == 0x0) {
1835 printk(KERN_WARNING "BIOS bug, APIC version is 0 for CPU#%d! "
1836 "fixing up to 0x10. (tell your hw vendor)\n",
1840 apic_version[apicid] = version;
1842 if (num_processors >= NR_CPUS) {
1843 printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
1844 " Processor ignored.\n", NR_CPUS);
1849 cpus_complement(tmp_map, cpu_present_map);
1850 cpu = first_cpu(tmp_map);
1852 physid_set(apicid, phys_cpu_present_map);
1853 if (apicid == boot_cpu_physical_apicid) {
1855 * x86_bios_cpu_apicid is required to have processors listed
1856 * in same order as logical cpu numbers. Hence the first
1857 * entry is BSP, and so on.
1861 if (apicid > max_physical_apicid)
1862 max_physical_apicid = apicid;
1864 #ifdef CONFIG_X86_32
1866 * Would be preferable to switch to bigsmp when CONFIG_HOTPLUG_CPU=y
1867 * but we need to work other dependencies like SMP_SUSPEND etc
1868 * before this can be done without some confusion.
1869 * if (CPU_HOTPLUG_ENABLED || num_processors > 8)
1870 * - Ashok Raj <ashok.raj@intel.com>
1872 if (max_physical_apicid >= 8) {
1873 switch (boot_cpu_data.x86_vendor) {
1874 case X86_VENDOR_INTEL:
1875 if (!APIC_XAPIC(version)) {
1879 /* If P4 and above fall through */
1880 case X86_VENDOR_AMD:
1886 #if defined(CONFIG_X86_SMP) || defined(CONFIG_X86_64)
1887 /* are we being called early in kernel startup? */
1888 if (early_per_cpu_ptr(x86_cpu_to_apicid)) {
1889 u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
1890 u16 *bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1892 cpu_to_apicid[cpu] = apicid;
1893 bios_cpu_apicid[cpu] = apicid;
1895 per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1896 per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1900 cpu_set(cpu, cpu_possible_map);
1901 cpu_set(cpu, cpu_present_map);
1904 #ifdef CONFIG_X86_64
1905 int hard_smp_processor_id(void)
1907 return read_apic_id();
1918 * 'active' is true if the local APIC was enabled by us and
1919 * not the BIOS; this signifies that we are also responsible
1920 * for disabling it before entering apm/acpi suspend
1923 /* r/w apic fields */
1924 unsigned int apic_id;
1925 unsigned int apic_taskpri;
1926 unsigned int apic_ldr;
1927 unsigned int apic_dfr;
1928 unsigned int apic_spiv;
1929 unsigned int apic_lvtt;
1930 unsigned int apic_lvtpc;
1931 unsigned int apic_lvt0;
1932 unsigned int apic_lvt1;
1933 unsigned int apic_lvterr;
1934 unsigned int apic_tmict;
1935 unsigned int apic_tdcr;
1936 unsigned int apic_thmr;
1939 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1941 unsigned long flags;
1944 if (!apic_pm_state.active)
1947 maxlvt = lapic_get_maxlvt();
1949 apic_pm_state.apic_id = apic_read(APIC_ID);
1950 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1951 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1952 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1953 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1954 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1956 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1957 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1958 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1959 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1960 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1961 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1962 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
1964 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1967 local_irq_save(flags);
1968 disable_local_APIC();
1969 local_irq_restore(flags);
1973 static int lapic_resume(struct sys_device *dev)
1976 unsigned long flags;
1979 if (!apic_pm_state.active)
1982 maxlvt = lapic_get_maxlvt();
1984 local_irq_save(flags);
1993 * Make sure the APICBASE points to the right address
1995 * FIXME! This will be wrong if we ever support suspend on
1996 * SMP! We'll need to do this as part of the CPU restore!
1998 rdmsr(MSR_IA32_APICBASE, l, h);
1999 l &= ~MSR_IA32_APICBASE_BASE;
2000 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2001 wrmsr(MSR_IA32_APICBASE, l, h);
2004 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2005 apic_write(APIC_ID, apic_pm_state.apic_id);
2006 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2007 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2008 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2009 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2010 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2011 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2012 #if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2014 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2017 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2018 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2019 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2020 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2021 apic_write(APIC_ESR, 0);
2022 apic_read(APIC_ESR);
2023 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2024 apic_write(APIC_ESR, 0);
2025 apic_read(APIC_ESR);
2027 local_irq_restore(flags);
2033 * This device has no shutdown method - fully functioning local APICs
2034 * are needed on every CPU up until machine_halt/restart/poweroff.
2037 static struct sysdev_class lapic_sysclass = {
2039 .resume = lapic_resume,
2040 .suspend = lapic_suspend,
2043 static struct sys_device device_lapic = {
2045 .cls = &lapic_sysclass,
2048 static void __cpuinit apic_pm_activate(void)
2050 apic_pm_state.active = 1;
2053 static int __init init_lapic_sysfs(void)
2059 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2061 error = sysdev_class_register(&lapic_sysclass);
2063 error = sysdev_register(&device_lapic);
2066 device_initcall(init_lapic_sysfs);
2068 #else /* CONFIG_PM */
2070 static void apic_pm_activate(void) { }
2072 #endif /* CONFIG_PM */
2074 #ifdef CONFIG_X86_64
2076 * apic_is_clustered_box() -- Check if we can expect good TSC
2078 * Thus far, the major user of this is IBM's Summit2 series:
2080 * Clustered boxes may have unsynced TSC problems if they are
2081 * multi-chassis. Use available data to take a good guess.
2082 * If in doubt, go HPET.
2084 __cpuinit int apic_is_clustered_box(void)
2086 int i, clusters, zeros;
2088 u16 *bios_cpu_apicid;
2089 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2092 * there is not this kind of box with AMD CPU yet.
2093 * Some AMD box with quadcore cpu and 8 sockets apicid
2094 * will be [4, 0x23] or [8, 0x27] could be thought to
2095 * vsmp box still need checking...
2097 if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
2100 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2101 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2103 for (i = 0; i < NR_CPUS; i++) {
2104 /* are we being called early in kernel startup? */
2105 if (bios_cpu_apicid) {
2106 id = bios_cpu_apicid[i];
2108 else if (i < nr_cpu_ids) {
2110 id = per_cpu(x86_bios_cpu_apicid, i);
2117 if (id != BAD_APICID)
2118 __set_bit(APIC_CLUSTERID(id), clustermap);
2121 /* Problem: Partially populated chassis may not have CPUs in some of
2122 * the APIC clusters they have been allocated. Only present CPUs have
2123 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2124 * Since clusters are allocated sequentially, count zeros only if
2125 * they are bounded by ones.
2129 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2130 if (test_bit(i, clustermap)) {
2131 clusters += 1 + zeros;
2137 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2138 * not guaranteed to be synced between boards
2140 if (is_vsmp_box() && clusters > 1)
2144 * If clusters > 2, then should be multi-chassis.
2145 * May have to revisit this when multi-core + hyperthreaded CPUs come
2146 * out, but AFAIK this will work even for them.
2148 return (clusters > 2);
2153 * APIC command line parameters
2155 static int __init setup_disableapic(char *arg)
2158 setup_clear_cpu_cap(X86_FEATURE_APIC);
2161 early_param("disableapic", setup_disableapic);
2163 /* same as disableapic, for compatibility */
2164 static int __init setup_nolapic(char *arg)
2166 return setup_disableapic(arg);
2168 early_param("nolapic", setup_nolapic);
2170 static int __init parse_lapic_timer_c2_ok(char *arg)
2172 local_apic_timer_c2_ok = 1;
2175 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2177 static int __init parse_disable_apic_timer(char *arg)
2179 disable_apic_timer = 1;
2182 early_param("noapictimer", parse_disable_apic_timer);
2184 static int __init parse_nolapic_timer(char *arg)
2186 disable_apic_timer = 1;
2189 early_param("nolapic_timer", parse_nolapic_timer);
2191 static int __init apic_set_verbosity(char *arg)
2194 #ifdef CONFIG_X86_64
2195 skip_ioapic_setup = 0;
2201 if (strcmp("debug", arg) == 0)
2202 apic_verbosity = APIC_DEBUG;
2203 else if (strcmp("verbose", arg) == 0)
2204 apic_verbosity = APIC_VERBOSE;
2206 printk(KERN_WARNING "APIC Verbosity level %s not recognised"
2207 " use apic=verbose or apic=debug\n", arg);
2213 early_param("apic", apic_set_verbosity);
2215 static int __init lapic_insert_resource(void)
2220 /* Put local APIC into the resource map. */
2221 lapic_resource.start = apic_phys;
2222 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2223 insert_resource(&iomem_resource, &lapic_resource);
2229 * need call insert after e820_reserve_resources()
2230 * that is using request_resource
2232 late_initcall(lapic_insert_resource);