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>
37 #include <asm/pgalloc.h>
40 #include <asm/proto.h>
41 #include <asm/timex.h>
43 #include <asm/i8259.h>
46 #include <mach_apic.h>
48 static int disable_apic_timer __cpuinitdata;
49 static int apic_calibrate_pmtmr __initdata;
54 /* x2apic enabled before OS handover */
55 int x2apic_preenabled;
57 /* Local APIC timer works in C2 */
58 int local_apic_timer_c2_ok;
59 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
62 * Debug level, exported for io_apic.c
64 unsigned int apic_verbosity;
66 /* Have we found an MP table */
69 static struct resource lapic_resource = {
71 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
74 static unsigned int calibration_result;
76 static int lapic_next_event(unsigned long delta,
77 struct clock_event_device *evt);
78 static void lapic_timer_setup(enum clock_event_mode mode,
79 struct clock_event_device *evt);
80 static void lapic_timer_broadcast(cpumask_t mask);
81 static void apic_pm_activate(void);
83 static struct clock_event_device lapic_clockevent = {
85 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
86 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
88 .set_mode = lapic_timer_setup,
89 .set_next_event = lapic_next_event,
90 .broadcast = lapic_timer_broadcast,
94 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
96 static unsigned long apic_phys;
98 unsigned long mp_lapic_addr;
101 * Get the LAPIC version
103 static inline int lapic_get_version(void)
105 return GET_APIC_VERSION(apic_read(APIC_LVR));
109 * Check, if the APIC is integrated or a seperate chip
111 static inline int lapic_is_integrated(void)
117 * Check, whether this is a modern or a first generation APIC
119 static int modern_apic(void)
121 /* AMD systems use old APIC versions, so check the CPU */
122 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
123 boot_cpu_data.x86 >= 0xf)
125 return lapic_get_version() >= 0x14;
128 void xapic_wait_icr_idle(void)
130 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
134 u32 safe_xapic_wait_icr_idle(void)
141 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
145 } while (timeout++ < 1000);
150 void xapic_icr_write(u32 low, u32 id)
152 apic_write(APIC_ICR2, id << 24);
153 apic_write(APIC_ICR, low);
156 u64 xapic_icr_read(void)
160 icr2 = apic_read(APIC_ICR2);
161 icr1 = apic_read(APIC_ICR);
163 return (icr1 | ((u64)icr2 << 32));
166 static struct apic_ops xapic_ops = {
167 .read = native_apic_mem_read,
168 .write = native_apic_mem_write,
169 .icr_read = xapic_icr_read,
170 .icr_write = xapic_icr_write,
171 .wait_icr_idle = xapic_wait_icr_idle,
172 .safe_wait_icr_idle = safe_xapic_wait_icr_idle,
175 struct apic_ops __read_mostly *apic_ops = &xapic_ops;
177 EXPORT_SYMBOL_GPL(apic_ops);
179 static void x2apic_wait_icr_idle(void)
181 /* no need to wait for icr idle in x2apic */
185 static u32 safe_x2apic_wait_icr_idle(void)
187 /* no need to wait for icr idle in x2apic */
191 void x2apic_icr_write(u32 low, u32 id)
193 wrmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), ((__u64) id) << 32 | low);
196 u64 x2apic_icr_read(void)
200 rdmsrl(APIC_BASE_MSR + (APIC_ICR >> 4), val);
204 static struct apic_ops x2apic_ops = {
205 .read = native_apic_msr_read,
206 .write = native_apic_msr_write,
207 .icr_read = x2apic_icr_read,
208 .icr_write = x2apic_icr_write,
209 .wait_icr_idle = x2apic_wait_icr_idle,
210 .safe_wait_icr_idle = safe_x2apic_wait_icr_idle,
214 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
216 void __cpuinit enable_NMI_through_LVT0(void)
220 /* unmask and set to NMI */
222 apic_write(APIC_LVT0, v);
226 * lapic_get_maxlvt - get the maximum number of local vector table entries
228 int lapic_get_maxlvt(void)
230 unsigned int v, maxlvt;
232 v = apic_read(APIC_LVR);
233 maxlvt = GET_APIC_MAXLVT(v);
238 * This function sets up the local APIC timer, with a timeout of
239 * 'clocks' APIC bus clock. During calibration we actually call
240 * this function twice on the boot CPU, once with a bogus timeout
241 * value, second time for real. The other (noncalibrating) CPUs
242 * call this function only once, with the real, calibrated value.
244 * We do reads before writes even if unnecessary, to get around the
245 * P5 APIC double write bug.
248 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
250 unsigned int lvtt_value, tmp_value;
252 lvtt_value = LOCAL_TIMER_VECTOR;
254 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
256 lvtt_value |= APIC_LVT_MASKED;
258 apic_write(APIC_LVTT, lvtt_value);
263 tmp_value = apic_read(APIC_TDCR);
264 apic_write(APIC_TDCR, (tmp_value
265 & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
269 apic_write(APIC_TMICT, clocks);
273 * Setup extended LVT, AMD specific (K8, family 10h)
275 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
276 * MCE interrupts are supported. Thus MCE offset must be set to 0.
279 #define APIC_EILVT_LVTOFF_MCE 0
280 #define APIC_EILVT_LVTOFF_IBS 1
282 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
284 unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
285 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
290 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
292 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
293 return APIC_EILVT_LVTOFF_MCE;
296 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
298 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
299 return APIC_EILVT_LVTOFF_IBS;
303 * Program the next event, relative to now
305 static int lapic_next_event(unsigned long delta,
306 struct clock_event_device *evt)
308 apic_write(APIC_TMICT, delta);
313 * Setup the lapic timer in periodic or oneshot mode
315 static void lapic_timer_setup(enum clock_event_mode mode,
316 struct clock_event_device *evt)
321 /* Lapic used as dummy for broadcast ? */
322 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
325 local_irq_save(flags);
328 case CLOCK_EVT_MODE_PERIODIC:
329 case CLOCK_EVT_MODE_ONESHOT:
330 __setup_APIC_LVTT(calibration_result,
331 mode != CLOCK_EVT_MODE_PERIODIC, 1);
333 case CLOCK_EVT_MODE_UNUSED:
334 case CLOCK_EVT_MODE_SHUTDOWN:
335 v = apic_read(APIC_LVTT);
336 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
337 apic_write(APIC_LVTT, v);
339 case CLOCK_EVT_MODE_RESUME:
340 /* Nothing to do here */
344 local_irq_restore(flags);
348 * Local APIC timer broadcast function
350 static void lapic_timer_broadcast(cpumask_t mask)
353 send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
358 * Setup the local APIC timer for this CPU. Copy the initilized values
359 * of the boot CPU and register the clock event in the framework.
361 static void setup_APIC_timer(void)
363 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
365 memcpy(levt, &lapic_clockevent, sizeof(*levt));
366 levt->cpumask = cpumask_of_cpu(smp_processor_id());
368 clockevents_register_device(levt);
372 * In this function we calibrate APIC bus clocks to the external
373 * timer. Unfortunately we cannot use jiffies and the timer irq
374 * to calibrate, since some later bootup code depends on getting
375 * the first irq? Ugh.
377 * We want to do the calibration only once since we
378 * want to have local timer irqs syncron. CPUs connected
379 * by the same APIC bus have the very same bus frequency.
380 * And we want to have irqs off anyways, no accidental
384 #define TICK_COUNT 100000000
386 static int __init calibrate_APIC_clock(void)
388 unsigned apic, apic_start;
389 unsigned long tsc, tsc_start;
395 * Put whatever arbitrary (but long enough) timeout
396 * value into the APIC clock, we just want to get the
397 * counter running for calibration.
399 * No interrupt enable !
401 __setup_APIC_LVTT(250000000, 0, 0);
403 apic_start = apic_read(APIC_TMCCT);
404 #ifdef CONFIG_X86_PM_TIMER
405 if (apic_calibrate_pmtmr && pmtmr_ioport) {
406 pmtimer_wait(5000); /* 5ms wait */
407 apic = apic_read(APIC_TMCCT);
408 result = (apic_start - apic) * 1000L / 5;
415 apic = apic_read(APIC_TMCCT);
417 } while ((tsc - tsc_start) < TICK_COUNT &&
418 (apic_start - apic) < TICK_COUNT);
420 result = (apic_start - apic) * 1000L * tsc_khz /
426 printk(KERN_DEBUG "APIC timer calibration result %d\n", result);
428 printk(KERN_INFO "Detected %d.%03d MHz APIC timer.\n",
429 result / 1000 / 1000, result / 1000 % 1000);
431 /* Calculate the scaled math multiplication factor */
432 lapic_clockevent.mult = div_sc(result, NSEC_PER_SEC,
433 lapic_clockevent.shift);
434 lapic_clockevent.max_delta_ns =
435 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
436 lapic_clockevent.min_delta_ns =
437 clockevent_delta2ns(0xF, &lapic_clockevent);
439 calibration_result = result / HZ;
442 * Do a sanity check on the APIC calibration result
444 if (calibration_result < (1000000 / HZ)) {
446 "APIC frequency too slow, disabling apic timer\n");
454 * Setup the boot APIC
456 * Calibrate and verify the result.
458 void __init setup_boot_APIC_clock(void)
461 * The local apic timer can be disabled via the kernel commandline.
462 * Register the lapic timer as a dummy clock event source on SMP
463 * systems, so the broadcast mechanism is used. On UP systems simply
466 if (disable_apic_timer) {
467 printk(KERN_INFO "Disabling APIC timer\n");
468 /* No broadcast on UP ! */
469 if (num_possible_cpus() > 1) {
470 lapic_clockevent.mult = 1;
476 printk(KERN_INFO "Using local APIC timer interrupts.\n");
477 if (calibrate_APIC_clock()) {
478 /* No broadcast on UP ! */
479 if (num_possible_cpus() > 1)
485 * If nmi_watchdog is set to IO_APIC, we need the
486 * PIT/HPET going. Otherwise register lapic as a dummy
489 if (nmi_watchdog != NMI_IO_APIC)
490 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
492 printk(KERN_WARNING "APIC timer registered as dummy,"
493 " due to nmi_watchdog=%d!\n", nmi_watchdog);
498 void __cpuinit setup_secondary_APIC_clock(void)
504 * The guts of the apic timer interrupt
506 static void local_apic_timer_interrupt(void)
508 int cpu = smp_processor_id();
509 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
512 * Normally we should not be here till LAPIC has been initialized but
513 * in some cases like kdump, its possible that there is a pending LAPIC
514 * timer interrupt from previous kernel's context and is delivered in
515 * new kernel the moment interrupts are enabled.
517 * Interrupts are enabled early and LAPIC is setup much later, hence
518 * its possible that when we get here evt->event_handler is NULL.
519 * Check for event_handler being NULL and discard the interrupt as
522 if (!evt->event_handler) {
524 "Spurious LAPIC timer interrupt on cpu %d\n", cpu);
526 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
531 * the NMI deadlock-detector uses this.
533 add_pda(apic_timer_irqs, 1);
535 evt->event_handler(evt);
539 * Local APIC timer interrupt. This is the most natural way for doing
540 * local interrupts, but local timer interrupts can be emulated by
541 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
543 * [ if a single-CPU system runs an SMP kernel then we call the local
544 * interrupt as well. Thus we cannot inline the local irq ... ]
546 void smp_apic_timer_interrupt(struct pt_regs *regs)
548 struct pt_regs *old_regs = set_irq_regs(regs);
551 * NOTE! We'd better ACK the irq immediately,
552 * because timer handling can be slow.
556 * update_process_times() expects us to have done irq_enter().
557 * Besides, if we don't timer interrupts ignore the global
558 * interrupt lock, which is the WrongThing (tm) to do.
562 local_apic_timer_interrupt();
564 set_irq_regs(old_regs);
567 int setup_profiling_timer(unsigned int multiplier)
574 * Local APIC start and shutdown
578 * clear_local_APIC - shutdown the local APIC
580 * This is called, when a CPU is disabled and before rebooting, so the state of
581 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
582 * leftovers during boot.
584 void clear_local_APIC(void)
589 /* APIC hasn't been mapped yet */
593 maxlvt = lapic_get_maxlvt();
595 * Masking an LVT entry can trigger a local APIC error
596 * if the vector is zero. Mask LVTERR first to prevent this.
599 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
600 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
603 * Careful: we have to set masks only first to deassert
604 * any level-triggered sources.
606 v = apic_read(APIC_LVTT);
607 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
608 v = apic_read(APIC_LVT0);
609 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
610 v = apic_read(APIC_LVT1);
611 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
613 v = apic_read(APIC_LVTPC);
614 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
618 * Clean APIC state for other OSs:
620 apic_write(APIC_LVTT, APIC_LVT_MASKED);
621 apic_write(APIC_LVT0, APIC_LVT_MASKED);
622 apic_write(APIC_LVT1, APIC_LVT_MASKED);
624 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
626 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
627 apic_write(APIC_ESR, 0);
632 * disable_local_APIC - clear and disable the local APIC
634 void disable_local_APIC(void)
641 * Disable APIC (implies clearing of registers
644 value = apic_read(APIC_SPIV);
645 value &= ~APIC_SPIV_APIC_ENABLED;
646 apic_write(APIC_SPIV, value);
649 void lapic_shutdown(void)
656 local_irq_save(flags);
658 disable_local_APIC();
660 local_irq_restore(flags);
664 * This is to verify that we're looking at a real local APIC.
665 * Check these against your board if the CPUs aren't getting
666 * started for no apparent reason.
668 int __init verify_local_APIC(void)
670 unsigned int reg0, reg1;
673 * The version register is read-only in a real APIC.
675 reg0 = apic_read(APIC_LVR);
676 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
677 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
678 reg1 = apic_read(APIC_LVR);
679 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
682 * The two version reads above should print the same
683 * numbers. If the second one is different, then we
684 * poke at a non-APIC.
690 * Check if the version looks reasonably.
692 reg1 = GET_APIC_VERSION(reg0);
693 if (reg1 == 0x00 || reg1 == 0xff)
695 reg1 = lapic_get_maxlvt();
696 if (reg1 < 0x02 || reg1 == 0xff)
700 * The ID register is read/write in a real APIC.
702 reg0 = apic_read(APIC_ID);
703 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
704 apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
705 reg1 = apic_read(APIC_ID);
706 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
707 apic_write(APIC_ID, reg0);
708 if (reg1 != (reg0 ^ APIC_ID_MASK))
712 * The next two are just to see if we have sane values.
713 * They're only really relevant if we're in Virtual Wire
714 * compatibility mode, but most boxes are anymore.
716 reg0 = apic_read(APIC_LVT0);
717 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
718 reg1 = apic_read(APIC_LVT1);
719 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
725 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
727 void __init sync_Arb_IDs(void)
729 /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 */
736 apic_wait_icr_idle();
738 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
739 apic_write(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
744 * An initial setup of the virtual wire mode.
746 void __init init_bsp_APIC(void)
751 * Don't do the setup now if we have a SMP BIOS as the
752 * through-I/O-APIC virtual wire mode might be active.
754 if (smp_found_config || !cpu_has_apic)
757 value = apic_read(APIC_LVR);
760 * Do not trust the local APIC being empty at bootup.
767 value = apic_read(APIC_SPIV);
768 value &= ~APIC_VECTOR_MASK;
769 value |= APIC_SPIV_APIC_ENABLED;
770 value |= APIC_SPIV_FOCUS_DISABLED;
771 value |= SPURIOUS_APIC_VECTOR;
772 apic_write(APIC_SPIV, value);
775 * Set up the virtual wire mode.
777 apic_write(APIC_LVT0, APIC_DM_EXTINT);
779 apic_write(APIC_LVT1, value);
783 * setup_local_APIC - setup the local APIC
785 void __cpuinit setup_local_APIC(void)
791 value = apic_read(APIC_LVR);
793 BUILD_BUG_ON((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f);
796 * Double-check whether this APIC is really registered.
797 * This is meaningless in clustered apic mode, so we skip it.
799 if (!apic_id_registered())
803 * Intel recommends to set DFR, LDR and TPR before enabling
804 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
805 * document number 292116). So here it goes...
810 * Set Task Priority to 'accept all'. We never change this
813 value = apic_read(APIC_TASKPRI);
814 value &= ~APIC_TPRI_MASK;
815 apic_write(APIC_TASKPRI, value);
818 * After a crash, we no longer service the interrupts and a pending
819 * interrupt from previous kernel might still have ISR bit set.
821 * Most probably by now CPU has serviced that pending interrupt and
822 * it might not have done the ack_APIC_irq() because it thought,
823 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
824 * does not clear the ISR bit and cpu thinks it has already serivced
825 * the interrupt. Hence a vector might get locked. It was noticed
826 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
828 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
829 value = apic_read(APIC_ISR + i*0x10);
830 for (j = 31; j >= 0; j--) {
837 * Now that we are all set up, enable the APIC
839 value = apic_read(APIC_SPIV);
840 value &= ~APIC_VECTOR_MASK;
844 value |= APIC_SPIV_APIC_ENABLED;
846 /* We always use processor focus */
849 * Set spurious IRQ vector
851 value |= SPURIOUS_APIC_VECTOR;
852 apic_write(APIC_SPIV, value);
857 * set up through-local-APIC on the BP's LINT0. This is not
858 * strictly necessary in pure symmetric-IO mode, but sometimes
859 * we delegate interrupts to the 8259A.
862 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
864 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
865 if (!smp_processor_id() && !value) {
866 value = APIC_DM_EXTINT;
867 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
870 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
871 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
874 apic_write(APIC_LVT0, value);
877 * only the BP should see the LINT1 NMI signal, obviously.
879 if (!smp_processor_id())
882 value = APIC_DM_NMI | APIC_LVT_MASKED;
883 apic_write(APIC_LVT1, value);
887 static void __cpuinit lapic_setup_esr(void)
889 unsigned maxlvt = lapic_get_maxlvt();
891 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR);
893 * spec says clear errors after enabling vector.
896 apic_write(APIC_ESR, 0);
899 void __cpuinit end_local_APIC_setup(void)
902 setup_apic_nmi_watchdog(NULL);
906 void check_x2apic(void)
910 rdmsr(MSR_IA32_APICBASE, msr, msr2);
912 if (msr & X2APIC_ENABLE) {
913 printk("x2apic enabled by BIOS, switching to x2apic ops\n");
914 x2apic_preenabled = x2apic = 1;
915 apic_ops = &x2apic_ops;
919 void enable_x2apic(void)
923 rdmsr(MSR_IA32_APICBASE, msr, msr2);
924 if (!(msr & X2APIC_ENABLE)) {
925 printk("Enabling x2apic\n");
926 wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
930 void enable_IR_x2apic(void)
932 #ifdef CONFIG_INTR_REMAP
939 if (!x2apic_preenabled && disable_x2apic) {
941 "Skipped enabling x2apic and Interrupt-remapping "
942 "because of nox2apic\n");
946 if (x2apic_preenabled && disable_x2apic)
947 panic("Bios already enabled x2apic, can't enforce nox2apic");
949 if (!x2apic_preenabled && skip_ioapic_setup) {
951 "Skipped enabling x2apic and Interrupt-remapping "
952 "because of skipping io-apic setup\n");
956 ret = dmar_table_init();
959 "dmar_table_init() failed with %d:\n", ret);
961 if (x2apic_preenabled)
962 panic("x2apic enabled by bios. But IR enabling failed");
965 "Not enabling x2apic,Intr-remapping\n");
969 local_irq_save(flags);
971 save_mask_IO_APIC_setup();
973 ret = enable_intr_remapping(1);
975 if (ret && x2apic_preenabled) {
976 local_irq_restore(flags);
977 panic("x2apic enabled by bios. But IR enabling failed");
985 apic_ops = &x2apic_ops;
993 restore_IO_APIC_setup();
995 reinit_intr_remapped_IO_APIC(x2apic_preenabled);
998 local_irq_restore(flags);
1001 if (!x2apic_preenabled)
1003 "Enabled x2apic and interrupt-remapping\n");
1006 "Enabled Interrupt-remapping\n");
1009 "Failed to enable Interrupt-remapping and x2apic\n");
1011 if (!cpu_has_x2apic)
1014 if (x2apic_preenabled)
1015 panic("x2apic enabled prior OS handover,"
1016 " enable CONFIG_INTR_REMAP");
1018 printk(KERN_INFO "Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1026 * Detect and enable local APICs on non-SMP boards.
1027 * Original code written by Keir Fraser.
1028 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1029 * not correctly set up (usually the APIC timer won't work etc.)
1031 static int __init detect_init_APIC(void)
1033 if (!cpu_has_apic) {
1034 printk(KERN_INFO "No local APIC present\n");
1038 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1039 boot_cpu_physical_apicid = 0;
1043 void __init early_init_lapic_mapping(void)
1045 unsigned long phys_addr;
1048 * If no local APIC can be found then go out
1049 * : it means there is no mpatable and MADT
1051 if (!smp_found_config)
1054 phys_addr = mp_lapic_addr;
1056 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
1057 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1058 APIC_BASE, phys_addr);
1061 * Fetch the APIC ID of the BSP in case we have a
1062 * default configuration (or the MP table is broken).
1064 boot_cpu_physical_apicid = read_apic_id();
1068 * init_apic_mappings - initialize APIC mappings
1070 void __init init_apic_mappings(void)
1073 boot_cpu_physical_apicid = read_apic_id();
1078 * If no local APIC can be found then set up a fake all
1079 * zeroes page to simulate the local APIC and another
1080 * one for the IO-APIC.
1082 if (!smp_found_config && detect_init_APIC()) {
1083 apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
1084 apic_phys = __pa(apic_phys);
1086 apic_phys = mp_lapic_addr;
1088 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
1089 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1090 APIC_BASE, apic_phys);
1093 * Fetch the APIC ID of the BSP in case we have a
1094 * default configuration (or the MP table is broken).
1096 boot_cpu_physical_apicid = read_apic_id();
1100 * This initializes the IO-APIC and APIC hardware if this is
1103 int __init APIC_init_uniprocessor(void)
1106 printk(KERN_INFO "Apic disabled\n");
1109 if (!cpu_has_apic) {
1111 printk(KERN_INFO "Apic disabled by BIOS\n");
1116 setup_apic_routing();
1118 verify_local_APIC();
1122 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1123 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1128 * Now enable IO-APICs, actually call clear_IO_APIC
1129 * We need clear_IO_APIC before enabling vector on BP
1131 if (!skip_ioapic_setup && nr_ioapics)
1134 if (!smp_found_config || skip_ioapic_setup || !nr_ioapics)
1135 localise_nmi_watchdog();
1136 end_local_APIC_setup();
1138 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1142 setup_boot_APIC_clock();
1143 check_nmi_watchdog();
1148 * Local APIC interrupts
1152 * This interrupt should _never_ happen with our APIC/SMP architecture
1154 asmlinkage void smp_spurious_interrupt(void)
1160 * Check if this really is a spurious interrupt and ACK it
1161 * if it is a vectored one. Just in case...
1162 * Spurious interrupts should not be ACKed.
1164 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1165 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1168 add_pda(irq_spurious_count, 1);
1173 * This interrupt should never happen with our APIC/SMP architecture
1175 asmlinkage void smp_error_interrupt(void)
1181 /* First tickle the hardware, only then report what went on. -- REW */
1182 v = apic_read(APIC_ESR);
1183 apic_write(APIC_ESR, 0);
1184 v1 = apic_read(APIC_ESR);
1186 atomic_inc(&irq_err_count);
1188 /* Here is what the APIC error bits mean:
1191 2: Send accept error
1192 3: Receive accept error
1194 5: Send illegal vector
1195 6: Received illegal vector
1196 7: Illegal register address
1198 printk(KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
1199 smp_processor_id(), v , v1);
1204 * * connect_bsp_APIC - attach the APIC to the interrupt system
1206 void __init connect_bsp_APIC(void)
1211 void disconnect_bsp_APIC(int virt_wire_setup)
1213 /* Go back to Virtual Wire compatibility mode */
1214 unsigned long value;
1216 /* For the spurious interrupt use vector F, and enable it */
1217 value = apic_read(APIC_SPIV);
1218 value &= ~APIC_VECTOR_MASK;
1219 value |= APIC_SPIV_APIC_ENABLED;
1221 apic_write(APIC_SPIV, value);
1223 if (!virt_wire_setup) {
1225 * For LVT0 make it edge triggered, active high,
1226 * external and enabled
1228 value = apic_read(APIC_LVT0);
1229 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1230 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1231 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1232 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1233 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1234 apic_write(APIC_LVT0, value);
1237 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1240 /* For LVT1 make it edge triggered, active high, nmi and enabled */
1241 value = apic_read(APIC_LVT1);
1242 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1243 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1244 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1245 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1246 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1247 apic_write(APIC_LVT1, value);
1250 void __cpuinit generic_processor_info(int apicid, int version)
1255 if (num_processors >= NR_CPUS) {
1256 printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
1257 " Processor ignored.\n", NR_CPUS);
1262 cpus_complement(tmp_map, cpu_present_map);
1263 cpu = first_cpu(tmp_map);
1265 physid_set(apicid, phys_cpu_present_map);
1266 if (apicid == boot_cpu_physical_apicid) {
1268 * x86_bios_cpu_apicid is required to have processors listed
1269 * in same order as logical cpu numbers. Hence the first
1270 * entry is BSP, and so on.
1274 if (apicid > max_physical_apicid)
1275 max_physical_apicid = apicid;
1277 /* are we being called early in kernel startup? */
1278 if (early_per_cpu_ptr(x86_cpu_to_apicid)) {
1279 u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
1280 u16 *bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1282 cpu_to_apicid[cpu] = apicid;
1283 bios_cpu_apicid[cpu] = apicid;
1285 per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1286 per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1289 cpu_set(cpu, cpu_possible_map);
1290 cpu_set(cpu, cpu_present_map);
1293 int hard_smp_processor_id(void)
1295 return read_apic_id();
1304 /* 'active' is true if the local APIC was enabled by us and
1305 not the BIOS; this signifies that we are also responsible
1306 for disabling it before entering apm/acpi suspend */
1308 /* r/w apic fields */
1309 unsigned int apic_id;
1310 unsigned int apic_taskpri;
1311 unsigned int apic_ldr;
1312 unsigned int apic_dfr;
1313 unsigned int apic_spiv;
1314 unsigned int apic_lvtt;
1315 unsigned int apic_lvtpc;
1316 unsigned int apic_lvt0;
1317 unsigned int apic_lvt1;
1318 unsigned int apic_lvterr;
1319 unsigned int apic_tmict;
1320 unsigned int apic_tdcr;
1321 unsigned int apic_thmr;
1324 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1326 unsigned long flags;
1329 if (!apic_pm_state.active)
1332 maxlvt = lapic_get_maxlvt();
1334 apic_pm_state.apic_id = apic_read(APIC_ID);
1335 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1336 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1337 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1338 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1339 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1341 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1342 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1343 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1344 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1345 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1346 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1347 #ifdef CONFIG_X86_MCE_INTEL
1349 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1351 local_irq_save(flags);
1352 disable_local_APIC();
1353 local_irq_restore(flags);
1357 static int lapic_resume(struct sys_device *dev)
1360 unsigned long flags;
1363 if (!apic_pm_state.active)
1366 maxlvt = lapic_get_maxlvt();
1368 local_irq_save(flags);
1370 rdmsr(MSR_IA32_APICBASE, l, h);
1371 l &= ~MSR_IA32_APICBASE_BASE;
1372 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
1373 wrmsr(MSR_IA32_APICBASE, l, h);
1377 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
1378 apic_write(APIC_ID, apic_pm_state.apic_id);
1379 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
1380 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
1381 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
1382 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
1383 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
1384 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
1385 #ifdef CONFIG_X86_MCE_INTEL
1387 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
1390 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
1391 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
1392 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
1393 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
1394 apic_write(APIC_ESR, 0);
1395 apic_read(APIC_ESR);
1396 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
1397 apic_write(APIC_ESR, 0);
1398 apic_read(APIC_ESR);
1399 local_irq_restore(flags);
1403 static struct sysdev_class lapic_sysclass = {
1405 .resume = lapic_resume,
1406 .suspend = lapic_suspend,
1409 static struct sys_device device_lapic = {
1411 .cls = &lapic_sysclass,
1414 static void __cpuinit apic_pm_activate(void)
1416 apic_pm_state.active = 1;
1419 static int __init init_lapic_sysfs(void)
1425 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
1427 error = sysdev_class_register(&lapic_sysclass);
1429 error = sysdev_register(&device_lapic);
1432 device_initcall(init_lapic_sysfs);
1434 #else /* CONFIG_PM */
1436 static void apic_pm_activate(void) { }
1438 #endif /* CONFIG_PM */
1441 * apic_is_clustered_box() -- Check if we can expect good TSC
1443 * Thus far, the major user of this is IBM's Summit2 series:
1445 * Clustered boxes may have unsynced TSC problems if they are
1446 * multi-chassis. Use available data to take a good guess.
1447 * If in doubt, go HPET.
1449 __cpuinit int apic_is_clustered_box(void)
1451 int i, clusters, zeros;
1453 u16 *bios_cpu_apicid;
1454 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
1457 * there is not this kind of box with AMD CPU yet.
1458 * Some AMD box with quadcore cpu and 8 sockets apicid
1459 * will be [4, 0x23] or [8, 0x27] could be thought to
1460 * vsmp box still need checking...
1462 if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
1465 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1466 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
1468 for (i = 0; i < NR_CPUS; i++) {
1469 /* are we being called early in kernel startup? */
1470 if (bios_cpu_apicid) {
1471 id = bios_cpu_apicid[i];
1473 else if (i < nr_cpu_ids) {
1475 id = per_cpu(x86_bios_cpu_apicid, i);
1482 if (id != BAD_APICID)
1483 __set_bit(APIC_CLUSTERID(id), clustermap);
1486 /* Problem: Partially populated chassis may not have CPUs in some of
1487 * the APIC clusters they have been allocated. Only present CPUs have
1488 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
1489 * Since clusters are allocated sequentially, count zeros only if
1490 * they are bounded by ones.
1494 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
1495 if (test_bit(i, clustermap)) {
1496 clusters += 1 + zeros;
1502 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
1503 * not guaranteed to be synced between boards
1505 if (is_vsmp_box() && clusters > 1)
1509 * If clusters > 2, then should be multi-chassis.
1510 * May have to revisit this when multi-core + hyperthreaded CPUs come
1511 * out, but AFAIK this will work even for them.
1513 return (clusters > 2);
1516 static __init int setup_nox2apic(char *str)
1519 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_X2APIC);
1522 early_param("nox2apic", setup_nox2apic);
1526 * APIC command line parameters
1528 static int __init apic_set_verbosity(char *str)
1531 skip_ioapic_setup = 0;
1535 if (strcmp("debug", str) == 0)
1536 apic_verbosity = APIC_DEBUG;
1537 else if (strcmp("verbose", str) == 0)
1538 apic_verbosity = APIC_VERBOSE;
1540 printk(KERN_WARNING "APIC Verbosity level %s not recognised"
1541 " use apic=verbose or apic=debug\n", str);
1547 early_param("apic", apic_set_verbosity);
1549 static __init int setup_disableapic(char *str)
1552 setup_clear_cpu_cap(X86_FEATURE_APIC);
1555 early_param("disableapic", setup_disableapic);
1557 /* same as disableapic, for compatibility */
1558 static __init int setup_nolapic(char *str)
1560 return setup_disableapic(str);
1562 early_param("nolapic", setup_nolapic);
1564 static int __init parse_lapic_timer_c2_ok(char *arg)
1566 local_apic_timer_c2_ok = 1;
1569 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
1571 static __init int setup_noapictimer(char *str)
1573 if (str[0] != ' ' && str[0] != 0)
1575 disable_apic_timer = 1;
1578 __setup("noapictimer", setup_noapictimer);
1580 static __init int setup_apicpmtimer(char *s)
1582 apic_calibrate_pmtmr = 1;
1586 __setup("apicpmtimer", setup_apicpmtimer);
1588 static int __init lapic_insert_resource(void)
1593 /* Put local APIC into the resource map. */
1594 lapic_resource.start = apic_phys;
1595 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
1596 insert_resource(&iomem_resource, &lapic_resource);
1602 * need call insert after e820_reserve_resources()
1603 * that is using request_resource
1605 late_initcall(lapic_insert_resource);