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>
31 #include <asm/atomic.h>
34 #include <asm/mpspec.h>
36 #include <asm/pgalloc.h>
39 #include <asm/proto.h>
40 #include <asm/timex.h>
44 #include <mach_apic.h>
46 static int disable_apic_timer __cpuinitdata;
47 static int apic_calibrate_pmtmr __initdata;
50 /* Local APIC timer works in C2 */
51 int local_apic_timer_c2_ok;
52 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
55 * Debug level, exported for io_apic.c
57 unsigned int apic_verbosity;
59 /* Have we found an MP table */
62 static struct resource lapic_resource = {
64 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
67 static unsigned int calibration_result;
69 static int lapic_next_event(unsigned long delta,
70 struct clock_event_device *evt);
71 static void lapic_timer_setup(enum clock_event_mode mode,
72 struct clock_event_device *evt);
73 static void lapic_timer_broadcast(cpumask_t mask);
74 static void apic_pm_activate(void);
76 static struct clock_event_device lapic_clockevent = {
78 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
79 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
81 .set_mode = lapic_timer_setup,
82 .set_next_event = lapic_next_event,
83 .broadcast = lapic_timer_broadcast,
87 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
89 static unsigned long apic_phys;
91 unsigned long mp_lapic_addr;
94 * Get the LAPIC version
96 static inline int lapic_get_version(void)
98 return GET_APIC_VERSION(apic_read(APIC_LVR));
102 * Check, if the APIC is integrated or a seperate chip
104 static inline int lapic_is_integrated(void)
110 * Check, whether this is a modern or a first generation APIC
112 static int modern_apic(void)
114 /* AMD systems use old APIC versions, so check the CPU */
115 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
116 boot_cpu_data.x86 >= 0xf)
118 return lapic_get_version() >= 0x14;
121 void apic_wait_icr_idle(void)
123 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
127 u32 safe_apic_wait_icr_idle(void)
134 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
138 } while (timeout++ < 1000);
144 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
146 void __cpuinit enable_NMI_through_LVT0(void)
150 /* unmask and set to NMI */
152 apic_write(APIC_LVT0, v);
156 * lapic_get_maxlvt - get the maximum number of local vector table entries
158 int lapic_get_maxlvt(void)
160 unsigned int v, maxlvt;
162 v = apic_read(APIC_LVR);
163 maxlvt = GET_APIC_MAXLVT(v);
168 * This function sets up the local APIC timer, with a timeout of
169 * 'clocks' APIC bus clock. During calibration we actually call
170 * this function twice on the boot CPU, once with a bogus timeout
171 * value, second time for real. The other (noncalibrating) CPUs
172 * call this function only once, with the real, calibrated value.
174 * We do reads before writes even if unnecessary, to get around the
175 * P5 APIC double write bug.
178 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
180 unsigned int lvtt_value, tmp_value;
182 lvtt_value = LOCAL_TIMER_VECTOR;
184 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
186 lvtt_value |= APIC_LVT_MASKED;
188 apic_write(APIC_LVTT, lvtt_value);
193 tmp_value = apic_read(APIC_TDCR);
194 apic_write(APIC_TDCR, (tmp_value
195 & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
199 apic_write(APIC_TMICT, clocks);
203 * Setup extended LVT, AMD specific (K8, family 10h)
205 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
206 * MCE interrupts are supported. Thus MCE offset must be set to 0.
208 * If mask=1, the LVT entry does not generate interrupts while mask=0
209 * enables the vector. See also the BKDGs.
212 #define APIC_EILVT_LVTOFF_MCE 0
213 #define APIC_EILVT_LVTOFF_IBS 1
215 static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
217 unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
218 unsigned int v = (mask << 16) | (msg_type << 8) | vector;
223 u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
225 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
226 return APIC_EILVT_LVTOFF_MCE;
229 u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
231 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
232 return APIC_EILVT_LVTOFF_IBS;
234 EXPORT_SYMBOL_GPL(setup_APIC_eilvt_ibs);
237 * Program the next event, relative to now
239 static int lapic_next_event(unsigned long delta,
240 struct clock_event_device *evt)
242 apic_write(APIC_TMICT, delta);
247 * Setup the lapic timer in periodic or oneshot mode
249 static void lapic_timer_setup(enum clock_event_mode mode,
250 struct clock_event_device *evt)
255 /* Lapic used as dummy for broadcast ? */
256 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
259 local_irq_save(flags);
262 case CLOCK_EVT_MODE_PERIODIC:
263 case CLOCK_EVT_MODE_ONESHOT:
264 __setup_APIC_LVTT(calibration_result,
265 mode != CLOCK_EVT_MODE_PERIODIC, 1);
267 case CLOCK_EVT_MODE_UNUSED:
268 case CLOCK_EVT_MODE_SHUTDOWN:
269 v = apic_read(APIC_LVTT);
270 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
271 apic_write(APIC_LVTT, v);
273 case CLOCK_EVT_MODE_RESUME:
274 /* Nothing to do here */
278 local_irq_restore(flags);
282 * Local APIC timer broadcast function
284 static void lapic_timer_broadcast(cpumask_t mask)
287 send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
292 * Setup the local APIC timer for this CPU. Copy the initilized values
293 * of the boot CPU and register the clock event in the framework.
295 static void setup_APIC_timer(void)
297 struct clock_event_device *levt = &__get_cpu_var(lapic_events);
299 memcpy(levt, &lapic_clockevent, sizeof(*levt));
300 levt->cpumask = cpumask_of_cpu(smp_processor_id());
302 clockevents_register_device(levt);
306 * In this function we calibrate APIC bus clocks to the external
307 * timer. Unfortunately we cannot use jiffies and the timer irq
308 * to calibrate, since some later bootup code depends on getting
309 * the first irq? Ugh.
311 * We want to do the calibration only once since we
312 * want to have local timer irqs syncron. CPUs connected
313 * by the same APIC bus have the very same bus frequency.
314 * And we want to have irqs off anyways, no accidental
318 #define TICK_COUNT 100000000
320 static int __init calibrate_APIC_clock(void)
322 unsigned apic, apic_start;
323 unsigned long tsc, tsc_start;
329 * Put whatever arbitrary (but long enough) timeout
330 * value into the APIC clock, we just want to get the
331 * counter running for calibration.
333 * No interrupt enable !
335 __setup_APIC_LVTT(250000000, 0, 0);
337 apic_start = apic_read(APIC_TMCCT);
338 #ifdef CONFIG_X86_PM_TIMER
339 if (apic_calibrate_pmtmr && pmtmr_ioport) {
340 pmtimer_wait(5000); /* 5ms wait */
341 apic = apic_read(APIC_TMCCT);
342 result = (apic_start - apic) * 1000L / 5;
349 apic = apic_read(APIC_TMCCT);
351 } while ((tsc - tsc_start) < TICK_COUNT &&
352 (apic_start - apic) < TICK_COUNT);
354 result = (apic_start - apic) * 1000L * tsc_khz /
360 printk(KERN_DEBUG "APIC timer calibration result %d\n", result);
362 printk(KERN_INFO "Detected %d.%03d MHz APIC timer.\n",
363 result / 1000 / 1000, result / 1000 % 1000);
365 /* Calculate the scaled math multiplication factor */
366 lapic_clockevent.mult = div_sc(result, NSEC_PER_SEC,
367 lapic_clockevent.shift);
368 lapic_clockevent.max_delta_ns =
369 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
370 lapic_clockevent.min_delta_ns =
371 clockevent_delta2ns(0xF, &lapic_clockevent);
373 calibration_result = result / HZ;
376 * Do a sanity check on the APIC calibration result
378 if (calibration_result < (1000000 / HZ)) {
380 "APIC frequency too slow, disabling apic timer\n");
388 * Setup the boot APIC
390 * Calibrate and verify the result.
392 void __init setup_boot_APIC_clock(void)
395 * The local apic timer can be disabled via the kernel commandline.
396 * Register the lapic timer as a dummy clock event source on SMP
397 * systems, so the broadcast mechanism is used. On UP systems simply
400 if (disable_apic_timer) {
401 printk(KERN_INFO "Disabling APIC timer\n");
402 /* No broadcast on UP ! */
403 if (num_possible_cpus() > 1) {
404 lapic_clockevent.mult = 1;
410 printk(KERN_INFO "Using local APIC timer interrupts.\n");
411 if (calibrate_APIC_clock()) {
412 /* No broadcast on UP ! */
413 if (num_possible_cpus() > 1)
419 * If nmi_watchdog is set to IO_APIC, we need the
420 * PIT/HPET going. Otherwise register lapic as a dummy
423 if (nmi_watchdog != NMI_IO_APIC)
424 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
426 printk(KERN_WARNING "APIC timer registered as dummy,"
427 " due to nmi_watchdog=%d!\n", nmi_watchdog);
432 void __cpuinit setup_secondary_APIC_clock(void)
438 * The guts of the apic timer interrupt
440 static void local_apic_timer_interrupt(void)
442 int cpu = smp_processor_id();
443 struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
446 * Normally we should not be here till LAPIC has been initialized but
447 * in some cases like kdump, its possible that there is a pending LAPIC
448 * timer interrupt from previous kernel's context and is delivered in
449 * new kernel the moment interrupts are enabled.
451 * Interrupts are enabled early and LAPIC is setup much later, hence
452 * its possible that when we get here evt->event_handler is NULL.
453 * Check for event_handler being NULL and discard the interrupt as
456 if (!evt->event_handler) {
458 "Spurious LAPIC timer interrupt on cpu %d\n", cpu);
460 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
465 * the NMI deadlock-detector uses this.
467 add_pda(apic_timer_irqs, 1);
469 evt->event_handler(evt);
473 * Local APIC timer interrupt. This is the most natural way for doing
474 * local interrupts, but local timer interrupts can be emulated by
475 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
477 * [ if a single-CPU system runs an SMP kernel then we call the local
478 * interrupt as well. Thus we cannot inline the local irq ... ]
480 void smp_apic_timer_interrupt(struct pt_regs *regs)
482 struct pt_regs *old_regs = set_irq_regs(regs);
485 * NOTE! We'd better ACK the irq immediately,
486 * because timer handling can be slow.
490 * update_process_times() expects us to have done irq_enter().
491 * Besides, if we don't timer interrupts ignore the global
492 * interrupt lock, which is the WrongThing (tm) to do.
496 local_apic_timer_interrupt();
498 set_irq_regs(old_regs);
501 int setup_profiling_timer(unsigned int multiplier)
508 * Local APIC start and shutdown
512 * clear_local_APIC - shutdown the local APIC
514 * This is called, when a CPU is disabled and before rebooting, so the state of
515 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
516 * leftovers during boot.
518 void clear_local_APIC(void)
523 /* APIC hasn't been mapped yet */
527 maxlvt = lapic_get_maxlvt();
529 * Masking an LVT entry can trigger a local APIC error
530 * if the vector is zero. Mask LVTERR first to prevent this.
533 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
534 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
537 * Careful: we have to set masks only first to deassert
538 * any level-triggered sources.
540 v = apic_read(APIC_LVTT);
541 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
542 v = apic_read(APIC_LVT0);
543 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
544 v = apic_read(APIC_LVT1);
545 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
547 v = apic_read(APIC_LVTPC);
548 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
552 * Clean APIC state for other OSs:
554 apic_write(APIC_LVTT, APIC_LVT_MASKED);
555 apic_write(APIC_LVT0, APIC_LVT_MASKED);
556 apic_write(APIC_LVT1, APIC_LVT_MASKED);
558 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
560 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
561 apic_write(APIC_ESR, 0);
566 * disable_local_APIC - clear and disable the local APIC
568 void disable_local_APIC(void)
575 * Disable APIC (implies clearing of registers
578 value = apic_read(APIC_SPIV);
579 value &= ~APIC_SPIV_APIC_ENABLED;
580 apic_write(APIC_SPIV, value);
583 void lapic_shutdown(void)
590 local_irq_save(flags);
592 disable_local_APIC();
594 local_irq_restore(flags);
598 * This is to verify that we're looking at a real local APIC.
599 * Check these against your board if the CPUs aren't getting
600 * started for no apparent reason.
602 int __init verify_local_APIC(void)
604 unsigned int reg0, reg1;
607 * The version register is read-only in a real APIC.
609 reg0 = apic_read(APIC_LVR);
610 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
611 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
612 reg1 = apic_read(APIC_LVR);
613 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
616 * The two version reads above should print the same
617 * numbers. If the second one is different, then we
618 * poke at a non-APIC.
624 * Check if the version looks reasonably.
626 reg1 = GET_APIC_VERSION(reg0);
627 if (reg1 == 0x00 || reg1 == 0xff)
629 reg1 = lapic_get_maxlvt();
630 if (reg1 < 0x02 || reg1 == 0xff)
634 * The ID register is read/write in a real APIC.
636 reg0 = read_apic_id();
637 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
638 apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
639 reg1 = read_apic_id();
640 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
641 apic_write(APIC_ID, reg0);
642 if (reg1 != (reg0 ^ APIC_ID_MASK))
646 * The next two are just to see if we have sane values.
647 * They're only really relevant if we're in Virtual Wire
648 * compatibility mode, but most boxes are anymore.
650 reg0 = apic_read(APIC_LVT0);
651 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
652 reg1 = apic_read(APIC_LVT1);
653 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
659 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
661 void __init sync_Arb_IDs(void)
663 /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 */
670 apic_wait_icr_idle();
672 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
673 apic_write(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
678 * An initial setup of the virtual wire mode.
680 void __init init_bsp_APIC(void)
685 * Don't do the setup now if we have a SMP BIOS as the
686 * through-I/O-APIC virtual wire mode might be active.
688 if (smp_found_config || !cpu_has_apic)
691 value = apic_read(APIC_LVR);
694 * Do not trust the local APIC being empty at bootup.
701 value = apic_read(APIC_SPIV);
702 value &= ~APIC_VECTOR_MASK;
703 value |= APIC_SPIV_APIC_ENABLED;
704 value |= APIC_SPIV_FOCUS_DISABLED;
705 value |= SPURIOUS_APIC_VECTOR;
706 apic_write(APIC_SPIV, value);
709 * Set up the virtual wire mode.
711 apic_write(APIC_LVT0, APIC_DM_EXTINT);
713 apic_write(APIC_LVT1, value);
717 * setup_local_APIC - setup the local APIC
719 void __cpuinit setup_local_APIC(void)
725 value = apic_read(APIC_LVR);
727 BUILD_BUG_ON((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f);
730 * Double-check whether this APIC is really registered.
731 * This is meaningless in clustered apic mode, so we skip it.
733 if (!apic_id_registered())
737 * Intel recommends to set DFR, LDR and TPR before enabling
738 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
739 * document number 292116). So here it goes...
744 * Set Task Priority to 'accept all'. We never change this
747 value = apic_read(APIC_TASKPRI);
748 value &= ~APIC_TPRI_MASK;
749 apic_write(APIC_TASKPRI, value);
752 * After a crash, we no longer service the interrupts and a pending
753 * interrupt from previous kernel might still have ISR bit set.
755 * Most probably by now CPU has serviced that pending interrupt and
756 * it might not have done the ack_APIC_irq() because it thought,
757 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
758 * does not clear the ISR bit and cpu thinks it has already serivced
759 * the interrupt. Hence a vector might get locked. It was noticed
760 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
762 for (i = APIC_ISR_NR - 1; i >= 0; i--) {
763 value = apic_read(APIC_ISR + i*0x10);
764 for (j = 31; j >= 0; j--) {
771 * Now that we are all set up, enable the APIC
773 value = apic_read(APIC_SPIV);
774 value &= ~APIC_VECTOR_MASK;
778 value |= APIC_SPIV_APIC_ENABLED;
780 /* We always use processor focus */
783 * Set spurious IRQ vector
785 value |= SPURIOUS_APIC_VECTOR;
786 apic_write(APIC_SPIV, value);
791 * set up through-local-APIC on the BP's LINT0. This is not
792 * strictly necessary in pure symmetric-IO mode, but sometimes
793 * we delegate interrupts to the 8259A.
796 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
798 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
799 if (!smp_processor_id() && !value) {
800 value = APIC_DM_EXTINT;
801 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
804 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
805 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
808 apic_write(APIC_LVT0, value);
811 * only the BP should see the LINT1 NMI signal, obviously.
813 if (!smp_processor_id())
816 value = APIC_DM_NMI | APIC_LVT_MASKED;
817 apic_write(APIC_LVT1, value);
821 static void __cpuinit lapic_setup_esr(void)
823 unsigned maxlvt = lapic_get_maxlvt();
825 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR);
827 * spec says clear errors after enabling vector.
830 apic_write(APIC_ESR, 0);
833 void __cpuinit end_local_APIC_setup(void)
836 setup_apic_nmi_watchdog(NULL);
841 * Detect and enable local APICs on non-SMP boards.
842 * Original code written by Keir Fraser.
843 * On AMD64 we trust the BIOS - if it says no APIC it is likely
844 * not correctly set up (usually the APIC timer won't work etc.)
846 static int __init detect_init_APIC(void)
849 printk(KERN_INFO "No local APIC present\n");
853 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
854 boot_cpu_physical_apicid = 0;
858 void __init early_init_lapic_mapping(void)
860 unsigned long phys_addr;
863 * If no local APIC can be found then go out
864 * : it means there is no mpatable and MADT
866 if (!smp_found_config)
869 phys_addr = mp_lapic_addr;
871 set_fixmap_nocache(FIX_APIC_BASE, phys_addr);
872 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
873 APIC_BASE, phys_addr);
876 * Fetch the APIC ID of the BSP in case we have a
877 * default configuration (or the MP table is broken).
879 boot_cpu_physical_apicid = GET_APIC_ID(read_apic_id());
883 * init_apic_mappings - initialize APIC mappings
885 void __init init_apic_mappings(void)
888 * If no local APIC can be found then set up a fake all
889 * zeroes page to simulate the local APIC and another
890 * one for the IO-APIC.
892 if (!smp_found_config && detect_init_APIC()) {
893 apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
894 apic_phys = __pa(apic_phys);
896 apic_phys = mp_lapic_addr;
898 set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
899 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
900 APIC_BASE, apic_phys);
903 * Fetch the APIC ID of the BSP in case we have a
904 * default configuration (or the MP table is broken).
906 boot_cpu_physical_apicid = GET_APIC_ID(read_apic_id());
910 * This initializes the IO-APIC and APIC hardware if this is
913 int __init APIC_init_uniprocessor(void)
916 printk(KERN_INFO "Apic disabled\n");
921 printk(KERN_INFO "Apic disabled by BIOS\n");
929 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
930 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
935 * Now enable IO-APICs, actually call clear_IO_APIC
936 * We need clear_IO_APIC before enabling vector on BP
938 if (!skip_ioapic_setup && nr_ioapics)
941 if (!smp_found_config || skip_ioapic_setup || !nr_ioapics)
942 localise_nmi_watchdog();
943 end_local_APIC_setup();
945 if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
949 setup_boot_APIC_clock();
950 check_nmi_watchdog();
955 * Local APIC interrupts
959 * This interrupt should _never_ happen with our APIC/SMP architecture
961 asmlinkage void smp_spurious_interrupt(void)
967 * Check if this really is a spurious interrupt and ACK it
968 * if it is a vectored one. Just in case...
969 * Spurious interrupts should not be ACKed.
971 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
972 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
975 add_pda(irq_spurious_count, 1);
980 * This interrupt should never happen with our APIC/SMP architecture
982 asmlinkage void smp_error_interrupt(void)
988 /* First tickle the hardware, only then report what went on. -- REW */
989 v = apic_read(APIC_ESR);
990 apic_write(APIC_ESR, 0);
991 v1 = apic_read(APIC_ESR);
993 atomic_inc(&irq_err_count);
995 /* Here is what the APIC error bits mean:
999 3: Receive accept error
1001 5: Send illegal vector
1002 6: Received illegal vector
1003 7: Illegal register address
1005 printk(KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
1006 smp_processor_id(), v , v1);
1011 * * connect_bsp_APIC - attach the APIC to the interrupt system
1013 void __init connect_bsp_APIC(void)
1018 void disconnect_bsp_APIC(int virt_wire_setup)
1020 /* Go back to Virtual Wire compatibility mode */
1021 unsigned long value;
1023 /* For the spurious interrupt use vector F, and enable it */
1024 value = apic_read(APIC_SPIV);
1025 value &= ~APIC_VECTOR_MASK;
1026 value |= APIC_SPIV_APIC_ENABLED;
1028 apic_write(APIC_SPIV, value);
1030 if (!virt_wire_setup) {
1032 * For LVT0 make it edge triggered, active high,
1033 * external and enabled
1035 value = apic_read(APIC_LVT0);
1036 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1037 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1038 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1039 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1040 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1041 apic_write(APIC_LVT0, value);
1044 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1047 /* For LVT1 make it edge triggered, active high, nmi and enabled */
1048 value = apic_read(APIC_LVT1);
1049 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1050 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1051 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1052 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1053 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1054 apic_write(APIC_LVT1, value);
1057 void __cpuinit generic_processor_info(int apicid, int version)
1062 if (num_processors >= NR_CPUS) {
1063 printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
1064 " Processor ignored.\n", NR_CPUS);
1069 cpus_complement(tmp_map, cpu_present_map);
1070 cpu = first_cpu(tmp_map);
1072 physid_set(apicid, phys_cpu_present_map);
1073 if (apicid == boot_cpu_physical_apicid) {
1075 * x86_bios_cpu_apicid is required to have processors listed
1076 * in same order as logical cpu numbers. Hence the first
1077 * entry is BSP, and so on.
1081 if (apicid > max_physical_apicid)
1082 max_physical_apicid = apicid;
1084 /* are we being called early in kernel startup? */
1085 if (early_per_cpu_ptr(x86_cpu_to_apicid)) {
1086 u16 *cpu_to_apicid = early_per_cpu_ptr(x86_cpu_to_apicid);
1087 u16 *bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1089 cpu_to_apicid[cpu] = apicid;
1090 bios_cpu_apicid[cpu] = apicid;
1092 per_cpu(x86_cpu_to_apicid, cpu) = apicid;
1093 per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
1096 cpu_set(cpu, cpu_possible_map);
1097 cpu_set(cpu, cpu_present_map);
1106 /* 'active' is true if the local APIC was enabled by us and
1107 not the BIOS; this signifies that we are also responsible
1108 for disabling it before entering apm/acpi suspend */
1110 /* r/w apic fields */
1111 unsigned int apic_id;
1112 unsigned int apic_taskpri;
1113 unsigned int apic_ldr;
1114 unsigned int apic_dfr;
1115 unsigned int apic_spiv;
1116 unsigned int apic_lvtt;
1117 unsigned int apic_lvtpc;
1118 unsigned int apic_lvt0;
1119 unsigned int apic_lvt1;
1120 unsigned int apic_lvterr;
1121 unsigned int apic_tmict;
1122 unsigned int apic_tdcr;
1123 unsigned int apic_thmr;
1126 static int lapic_suspend(struct sys_device *dev, pm_message_t state)
1128 unsigned long flags;
1131 if (!apic_pm_state.active)
1134 maxlvt = lapic_get_maxlvt();
1136 apic_pm_state.apic_id = read_apic_id();
1137 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
1138 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
1139 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
1140 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
1141 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
1143 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
1144 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
1145 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
1146 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
1147 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
1148 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
1149 #ifdef CONFIG_X86_MCE_INTEL
1151 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
1153 local_irq_save(flags);
1154 disable_local_APIC();
1155 local_irq_restore(flags);
1159 static int lapic_resume(struct sys_device *dev)
1162 unsigned long flags;
1165 if (!apic_pm_state.active)
1168 maxlvt = lapic_get_maxlvt();
1170 local_irq_save(flags);
1171 rdmsr(MSR_IA32_APICBASE, l, h);
1172 l &= ~MSR_IA32_APICBASE_BASE;
1173 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
1174 wrmsr(MSR_IA32_APICBASE, l, h);
1175 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
1176 apic_write(APIC_ID, apic_pm_state.apic_id);
1177 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
1178 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
1179 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
1180 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
1181 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
1182 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
1183 #ifdef CONFIG_X86_MCE_INTEL
1185 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
1188 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
1189 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
1190 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
1191 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
1192 apic_write(APIC_ESR, 0);
1193 apic_read(APIC_ESR);
1194 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
1195 apic_write(APIC_ESR, 0);
1196 apic_read(APIC_ESR);
1197 local_irq_restore(flags);
1201 static struct sysdev_class lapic_sysclass = {
1203 .resume = lapic_resume,
1204 .suspend = lapic_suspend,
1207 static struct sys_device device_lapic = {
1209 .cls = &lapic_sysclass,
1212 static void __cpuinit apic_pm_activate(void)
1214 apic_pm_state.active = 1;
1217 static int __init init_lapic_sysfs(void)
1223 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
1225 error = sysdev_class_register(&lapic_sysclass);
1227 error = sysdev_register(&device_lapic);
1230 device_initcall(init_lapic_sysfs);
1232 #else /* CONFIG_PM */
1234 static void apic_pm_activate(void) { }
1236 #endif /* CONFIG_PM */
1239 * apic_is_clustered_box() -- Check if we can expect good TSC
1241 * Thus far, the major user of this is IBM's Summit2 series:
1243 * Clustered boxes may have unsynced TSC problems if they are
1244 * multi-chassis. Use available data to take a good guess.
1245 * If in doubt, go HPET.
1247 __cpuinit int apic_is_clustered_box(void)
1249 int i, clusters, zeros;
1251 u16 *bios_cpu_apicid;
1252 DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
1255 * there is not this kind of box with AMD CPU yet.
1256 * Some AMD box with quadcore cpu and 8 sockets apicid
1257 * will be [4, 0x23] or [8, 0x27] could be thought to
1258 * vsmp box still need checking...
1260 if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
1263 bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
1264 bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
1266 for (i = 0; i < NR_CPUS; i++) {
1267 /* are we being called early in kernel startup? */
1268 if (bios_cpu_apicid) {
1269 id = bios_cpu_apicid[i];
1271 else if (i < nr_cpu_ids) {
1273 id = per_cpu(x86_bios_cpu_apicid, i);
1280 if (id != BAD_APICID)
1281 __set_bit(APIC_CLUSTERID(id), clustermap);
1284 /* Problem: Partially populated chassis may not have CPUs in some of
1285 * the APIC clusters they have been allocated. Only present CPUs have
1286 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
1287 * Since clusters are allocated sequentially, count zeros only if
1288 * they are bounded by ones.
1292 for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
1293 if (test_bit(i, clustermap)) {
1294 clusters += 1 + zeros;
1300 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
1301 * not guaranteed to be synced between boards
1303 if (is_vsmp_box() && clusters > 1)
1307 * If clusters > 2, then should be multi-chassis.
1308 * May have to revisit this when multi-core + hyperthreaded CPUs come
1309 * out, but AFAIK this will work even for them.
1311 return (clusters > 2);
1315 * APIC command line parameters
1317 static int __init apic_set_verbosity(char *str)
1320 skip_ioapic_setup = 0;
1324 if (strcmp("debug", str) == 0)
1325 apic_verbosity = APIC_DEBUG;
1326 else if (strcmp("verbose", str) == 0)
1327 apic_verbosity = APIC_VERBOSE;
1329 printk(KERN_WARNING "APIC Verbosity level %s not recognised"
1330 " use apic=verbose or apic=debug\n", str);
1336 early_param("apic", apic_set_verbosity);
1338 static __init int setup_disableapic(char *str)
1341 setup_clear_cpu_cap(X86_FEATURE_APIC);
1344 early_param("disableapic", setup_disableapic);
1346 /* same as disableapic, for compatibility */
1347 static __init int setup_nolapic(char *str)
1349 return setup_disableapic(str);
1351 early_param("nolapic", setup_nolapic);
1353 static int __init parse_lapic_timer_c2_ok(char *arg)
1355 local_apic_timer_c2_ok = 1;
1358 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
1360 static __init int setup_noapictimer(char *str)
1362 if (str[0] != ' ' && str[0] != 0)
1364 disable_apic_timer = 1;
1367 __setup("noapictimer", setup_noapictimer);
1369 static __init int setup_apicpmtimer(char *s)
1371 apic_calibrate_pmtmr = 1;
1375 __setup("apicpmtimer", setup_apicpmtimer);
1377 static int __init lapic_insert_resource(void)
1382 /* Put local APIC into the resource map. */
1383 lapic_resource.start = apic_phys;
1384 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
1385 insert_resource(&iomem_resource, &lapic_resource);
1391 * need call insert after e820_reserve_resources()
1392 * that is using request_resource
1394 late_initcall(lapic_insert_resource);