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 /* Disable local APIC timer from the kernel commandline or via dmi quirk */
49 static int disable_apic_timer __cpuinitdata
;
50 static int apic_calibrate_pmtmr __initdata
;
55 /* x2apic enabled before OS handover */
56 int x2apic_preenabled
;
58 /* Local APIC timer works in C2 */
59 int local_apic_timer_c2_ok
;
60 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok
);
63 * Debug level, exported for io_apic.c
65 unsigned int apic_verbosity
;
67 /* Have we found an MP table */
70 static struct resource lapic_resource
= {
72 .flags
= IORESOURCE_MEM
| IORESOURCE_BUSY
,
75 static unsigned int calibration_result
;
77 static int lapic_next_event(unsigned long delta
,
78 struct clock_event_device
*evt
);
79 static void lapic_timer_setup(enum clock_event_mode mode
,
80 struct clock_event_device
*evt
);
81 static void lapic_timer_broadcast(cpumask_t mask
);
82 static void apic_pm_activate(void);
84 static struct clock_event_device lapic_clockevent
= {
86 .features
= CLOCK_EVT_FEAT_PERIODIC
| CLOCK_EVT_FEAT_ONESHOT
87 | CLOCK_EVT_FEAT_C3STOP
| CLOCK_EVT_FEAT_DUMMY
,
89 .set_mode
= lapic_timer_setup
,
90 .set_next_event
= lapic_next_event
,
91 .broadcast
= lapic_timer_broadcast
,
95 static DEFINE_PER_CPU(struct clock_event_device
, lapic_events
);
97 static unsigned long apic_phys
;
99 unsigned long mp_lapic_addr
;
101 unsigned int __cpuinitdata maxcpus
= NR_CPUS
;
103 * Get the LAPIC version
105 static inline int lapic_get_version(void)
107 return GET_APIC_VERSION(apic_read(APIC_LVR
));
111 * Check, if the APIC is integrated or a seperate chip
113 static inline int lapic_is_integrated(void)
119 * Check, whether this is a modern or a first generation APIC
121 static int modern_apic(void)
123 /* AMD systems use old APIC versions, so check the CPU */
124 if (boot_cpu_data
.x86_vendor
== X86_VENDOR_AMD
&&
125 boot_cpu_data
.x86
>= 0xf)
127 return lapic_get_version() >= 0x14;
130 void xapic_wait_icr_idle(void)
132 while (apic_read(APIC_ICR
) & APIC_ICR_BUSY
)
136 u32
safe_xapic_wait_icr_idle(void)
143 send_status
= apic_read(APIC_ICR
) & APIC_ICR_BUSY
;
147 } while (timeout
++ < 1000);
152 void xapic_icr_write(u32 low
, u32 id
)
154 apic_write(APIC_ICR2
, SET_APIC_DEST_FIELD(id
));
155 apic_write(APIC_ICR
, low
);
158 u64
xapic_icr_read(void)
162 icr2
= apic_read(APIC_ICR2
);
163 icr1
= apic_read(APIC_ICR
);
165 return (icr1
| ((u64
)icr2
<< 32));
168 static struct apic_ops xapic_ops
= {
169 .read
= native_apic_mem_read
,
170 .write
= native_apic_mem_write
,
171 .icr_read
= xapic_icr_read
,
172 .icr_write
= xapic_icr_write
,
173 .wait_icr_idle
= xapic_wait_icr_idle
,
174 .safe_wait_icr_idle
= safe_xapic_wait_icr_idle
,
177 struct apic_ops __read_mostly
*apic_ops
= &xapic_ops
;
179 EXPORT_SYMBOL_GPL(apic_ops
);
181 static void x2apic_wait_icr_idle(void)
183 /* no need to wait for icr idle in x2apic */
187 static u32
safe_x2apic_wait_icr_idle(void)
189 /* no need to wait for icr idle in x2apic */
193 void x2apic_icr_write(u32 low
, u32 id
)
195 wrmsrl(APIC_BASE_MSR
+ (APIC_ICR
>> 4), ((__u64
) id
) << 32 | low
);
198 u64
x2apic_icr_read(void)
202 rdmsrl(APIC_BASE_MSR
+ (APIC_ICR
>> 4), val
);
206 static struct apic_ops x2apic_ops
= {
207 .read
= native_apic_msr_read
,
208 .write
= native_apic_msr_write
,
209 .icr_read
= x2apic_icr_read
,
210 .icr_write
= x2apic_icr_write
,
211 .wait_icr_idle
= x2apic_wait_icr_idle
,
212 .safe_wait_icr_idle
= safe_x2apic_wait_icr_idle
,
216 * enable_NMI_through_LVT0 - enable NMI through local vector table 0
218 void __cpuinit
enable_NMI_through_LVT0(void)
222 /* unmask and set to NMI */
225 /* Level triggered for 82489DX (32bit mode) */
226 if (!lapic_is_integrated())
227 v
|= APIC_LVT_LEVEL_TRIGGER
;
229 apic_write(APIC_LVT0
, v
);
233 * lapic_get_maxlvt - get the maximum number of local vector table entries
235 int lapic_get_maxlvt(void)
239 v
= apic_read(APIC_LVR
);
241 * - we always have APIC integrated on 64bit mode
242 * - 82489DXs do not report # of LVT entries
244 return APIC_INTEGRATED(GET_APIC_VERSION(v
)) ? GET_APIC_MAXLVT(v
) : 2;
247 /* Clock divisor is set to 1 */
248 #define APIC_DIVISOR 1
251 * This function sets up the local APIC timer, with a timeout of
252 * 'clocks' APIC bus clock. During calibration we actually call
253 * this function twice on the boot CPU, once with a bogus timeout
254 * value, second time for real. The other (noncalibrating) CPUs
255 * call this function only once, with the real, calibrated value.
257 * We do reads before writes even if unnecessary, to get around the
258 * P5 APIC double write bug.
261 static void __setup_APIC_LVTT(unsigned int clocks
, int oneshot
, int irqen
)
263 unsigned int lvtt_value
, tmp_value
;
265 lvtt_value
= LOCAL_TIMER_VECTOR
;
267 lvtt_value
|= APIC_LVT_TIMER_PERIODIC
;
268 if (!lapic_is_integrated())
269 lvtt_value
|= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV
);
272 lvtt_value
|= APIC_LVT_MASKED
;
274 apic_write(APIC_LVTT
, lvtt_value
);
279 tmp_value
= apic_read(APIC_TDCR
);
280 apic_write(APIC_TDCR
, (tmp_value
281 & ~(APIC_TDR_DIV_1
| APIC_TDR_DIV_TMBASE
))
285 apic_write(APIC_TMICT
, clocks
/ APIC_DIVISOR
);
289 * Setup extended LVT, AMD specific (K8, family 10h)
291 * Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
292 * MCE interrupts are supported. Thus MCE offset must be set to 0.
295 #define APIC_EILVT_LVTOFF_MCE 0
296 #define APIC_EILVT_LVTOFF_IBS 1
298 static void setup_APIC_eilvt(u8 lvt_off
, u8 vector
, u8 msg_type
, u8 mask
)
300 unsigned long reg
= (lvt_off
<< 4) + APIC_EILVT0
;
301 unsigned int v
= (mask
<< 16) | (msg_type
<< 8) | vector
;
306 u8
setup_APIC_eilvt_mce(u8 vector
, u8 msg_type
, u8 mask
)
308 setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE
, vector
, msg_type
, mask
);
309 return APIC_EILVT_LVTOFF_MCE
;
312 u8
setup_APIC_eilvt_ibs(u8 vector
, u8 msg_type
, u8 mask
)
314 setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS
, vector
, msg_type
, mask
);
315 return APIC_EILVT_LVTOFF_IBS
;
319 * Program the next event, relative to now
321 static int lapic_next_event(unsigned long delta
,
322 struct clock_event_device
*evt
)
324 apic_write(APIC_TMICT
, delta
);
329 * Setup the lapic timer in periodic or oneshot mode
331 static void lapic_timer_setup(enum clock_event_mode mode
,
332 struct clock_event_device
*evt
)
337 /* Lapic used as dummy for broadcast ? */
338 if (evt
->features
& CLOCK_EVT_FEAT_DUMMY
)
341 local_irq_save(flags
);
344 case CLOCK_EVT_MODE_PERIODIC
:
345 case CLOCK_EVT_MODE_ONESHOT
:
346 __setup_APIC_LVTT(calibration_result
,
347 mode
!= CLOCK_EVT_MODE_PERIODIC
, 1);
349 case CLOCK_EVT_MODE_UNUSED
:
350 case CLOCK_EVT_MODE_SHUTDOWN
:
351 v
= apic_read(APIC_LVTT
);
352 v
|= (APIC_LVT_MASKED
| LOCAL_TIMER_VECTOR
);
353 apic_write(APIC_LVTT
, v
);
355 case CLOCK_EVT_MODE_RESUME
:
356 /* Nothing to do here */
360 local_irq_restore(flags
);
364 * Local APIC timer broadcast function
366 static void lapic_timer_broadcast(cpumask_t mask
)
369 send_IPI_mask(mask
, LOCAL_TIMER_VECTOR
);
374 * Setup the local APIC timer for this CPU. Copy the initilized values
375 * of the boot CPU and register the clock event in the framework.
377 static void setup_APIC_timer(void)
379 struct clock_event_device
*levt
= &__get_cpu_var(lapic_events
);
381 memcpy(levt
, &lapic_clockevent
, sizeof(*levt
));
382 levt
->cpumask
= cpumask_of_cpu(smp_processor_id());
384 clockevents_register_device(levt
);
388 * In this function we calibrate APIC bus clocks to the external
389 * timer. Unfortunately we cannot use jiffies and the timer irq
390 * to calibrate, since some later bootup code depends on getting
391 * the first irq? Ugh.
393 * We want to do the calibration only once since we
394 * want to have local timer irqs syncron. CPUs connected
395 * by the same APIC bus have the very same bus frequency.
396 * And we want to have irqs off anyways, no accidental
400 #define TICK_COUNT 100000000
402 static int __init
calibrate_APIC_clock(void)
404 unsigned apic
, apic_start
;
405 unsigned long tsc
, tsc_start
;
411 * Put whatever arbitrary (but long enough) timeout
412 * value into the APIC clock, we just want to get the
413 * counter running for calibration.
415 * No interrupt enable !
417 __setup_APIC_LVTT(250000000, 0, 0);
419 apic_start
= apic_read(APIC_TMCCT
);
420 #ifdef CONFIG_X86_PM_TIMER
421 if (apic_calibrate_pmtmr
&& pmtmr_ioport
) {
422 pmtimer_wait(5000); /* 5ms wait */
423 apic
= apic_read(APIC_TMCCT
);
424 result
= (apic_start
- apic
) * 1000L / 5;
431 apic
= apic_read(APIC_TMCCT
);
433 } while ((tsc
- tsc_start
) < TICK_COUNT
&&
434 (apic_start
- apic
) < TICK_COUNT
);
436 result
= (apic_start
- apic
) * 1000L * tsc_khz
/
442 printk(KERN_DEBUG
"APIC timer calibration result %d\n", result
);
444 printk(KERN_INFO
"Detected %d.%03d MHz APIC timer.\n",
445 result
/ 1000 / 1000, result
/ 1000 % 1000);
447 /* Calculate the scaled math multiplication factor */
448 lapic_clockevent
.mult
= div_sc(result
, NSEC_PER_SEC
,
449 lapic_clockevent
.shift
);
450 lapic_clockevent
.max_delta_ns
=
451 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent
);
452 lapic_clockevent
.min_delta_ns
=
453 clockevent_delta2ns(0xF, &lapic_clockevent
);
455 calibration_result
= (result
* APIC_DIVISOR
) / HZ
;
458 * Do a sanity check on the APIC calibration result
460 if (calibration_result
< (1000000 / HZ
)) {
462 "APIC frequency too slow, disabling apic timer\n");
470 * Setup the boot APIC
472 * Calibrate and verify the result.
474 void __init
setup_boot_APIC_clock(void)
477 * The local apic timer can be disabled via the kernel commandline.
478 * Register the lapic timer as a dummy clock event source on SMP
479 * systems, so the broadcast mechanism is used. On UP systems simply
482 if (disable_apic_timer
) {
483 printk(KERN_INFO
"Disabling APIC timer\n");
484 /* No broadcast on UP ! */
485 if (num_possible_cpus() > 1) {
486 lapic_clockevent
.mult
= 1;
492 printk(KERN_INFO
"Using local APIC timer interrupts.\n");
493 if (calibrate_APIC_clock()) {
494 /* No broadcast on UP ! */
495 if (num_possible_cpus() > 1)
501 * If nmi_watchdog is set to IO_APIC, we need the
502 * PIT/HPET going. Otherwise register lapic as a dummy
505 if (nmi_watchdog
!= NMI_IO_APIC
)
506 lapic_clockevent
.features
&= ~CLOCK_EVT_FEAT_DUMMY
;
508 printk(KERN_WARNING
"APIC timer registered as dummy,"
509 " due to nmi_watchdog=%d!\n", nmi_watchdog
);
514 void __cpuinit
setup_secondary_APIC_clock(void)
520 * The guts of the apic timer interrupt
522 static void local_apic_timer_interrupt(void)
524 int cpu
= smp_processor_id();
525 struct clock_event_device
*evt
= &per_cpu(lapic_events
, cpu
);
528 * Normally we should not be here till LAPIC has been initialized but
529 * in some cases like kdump, its possible that there is a pending LAPIC
530 * timer interrupt from previous kernel's context and is delivered in
531 * new kernel the moment interrupts are enabled.
533 * Interrupts are enabled early and LAPIC is setup much later, hence
534 * its possible that when we get here evt->event_handler is NULL.
535 * Check for event_handler being NULL and discard the interrupt as
538 if (!evt
->event_handler
) {
540 "Spurious LAPIC timer interrupt on cpu %d\n", cpu
);
542 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN
, evt
);
547 * the NMI deadlock-detector uses this.
549 add_pda(apic_timer_irqs
, 1);
551 evt
->event_handler(evt
);
555 * Local APIC timer interrupt. This is the most natural way for doing
556 * local interrupts, but local timer interrupts can be emulated by
557 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
559 * [ if a single-CPU system runs an SMP kernel then we call the local
560 * interrupt as well. Thus we cannot inline the local irq ... ]
562 void smp_apic_timer_interrupt(struct pt_regs
*regs
)
564 struct pt_regs
*old_regs
= set_irq_regs(regs
);
567 * NOTE! We'd better ACK the irq immediately,
568 * because timer handling can be slow.
572 * update_process_times() expects us to have done irq_enter().
573 * Besides, if we don't timer interrupts ignore the global
574 * interrupt lock, which is the WrongThing (tm) to do.
578 local_apic_timer_interrupt();
580 set_irq_regs(old_regs
);
583 int setup_profiling_timer(unsigned int multiplier
)
590 * Local APIC start and shutdown
594 * clear_local_APIC - shutdown the local APIC
596 * This is called, when a CPU is disabled and before rebooting, so the state of
597 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
598 * leftovers during boot.
600 void clear_local_APIC(void)
605 /* APIC hasn't been mapped yet */
609 maxlvt
= lapic_get_maxlvt();
611 * Masking an LVT entry can trigger a local APIC error
612 * if the vector is zero. Mask LVTERR first to prevent this.
615 v
= ERROR_APIC_VECTOR
; /* any non-zero vector will do */
616 apic_write(APIC_LVTERR
, v
| APIC_LVT_MASKED
);
619 * Careful: we have to set masks only first to deassert
620 * any level-triggered sources.
622 v
= apic_read(APIC_LVTT
);
623 apic_write(APIC_LVTT
, v
| APIC_LVT_MASKED
);
624 v
= apic_read(APIC_LVT0
);
625 apic_write(APIC_LVT0
, v
| APIC_LVT_MASKED
);
626 v
= apic_read(APIC_LVT1
);
627 apic_write(APIC_LVT1
, v
| APIC_LVT_MASKED
);
629 v
= apic_read(APIC_LVTPC
);
630 apic_write(APIC_LVTPC
, v
| APIC_LVT_MASKED
);
634 * Clean APIC state for other OSs:
636 apic_write(APIC_LVTT
, APIC_LVT_MASKED
);
637 apic_write(APIC_LVT0
, APIC_LVT_MASKED
);
638 apic_write(APIC_LVT1
, APIC_LVT_MASKED
);
640 apic_write(APIC_LVTERR
, APIC_LVT_MASKED
);
642 apic_write(APIC_LVTPC
, APIC_LVT_MASKED
);
643 apic_write(APIC_ESR
, 0);
648 * disable_local_APIC - clear and disable the local APIC
650 void disable_local_APIC(void)
657 * Disable APIC (implies clearing of registers
660 value
= apic_read(APIC_SPIV
);
661 value
&= ~APIC_SPIV_APIC_ENABLED
;
662 apic_write(APIC_SPIV
, value
);
665 void lapic_shutdown(void)
672 local_irq_save(flags
);
674 disable_local_APIC();
676 local_irq_restore(flags
);
680 * This is to verify that we're looking at a real local APIC.
681 * Check these against your board if the CPUs aren't getting
682 * started for no apparent reason.
684 int __init
verify_local_APIC(void)
686 unsigned int reg0
, reg1
;
689 * The version register is read-only in a real APIC.
691 reg0
= apic_read(APIC_LVR
);
692 apic_printk(APIC_DEBUG
, "Getting VERSION: %x\n", reg0
);
693 apic_write(APIC_LVR
, reg0
^ APIC_LVR_MASK
);
694 reg1
= apic_read(APIC_LVR
);
695 apic_printk(APIC_DEBUG
, "Getting VERSION: %x\n", reg1
);
698 * The two version reads above should print the same
699 * numbers. If the second one is different, then we
700 * poke at a non-APIC.
706 * Check if the version looks reasonably.
708 reg1
= GET_APIC_VERSION(reg0
);
709 if (reg1
== 0x00 || reg1
== 0xff)
711 reg1
= lapic_get_maxlvt();
712 if (reg1
< 0x02 || reg1
== 0xff)
716 * The ID register is read/write in a real APIC.
718 reg0
= apic_read(APIC_ID
);
719 apic_printk(APIC_DEBUG
, "Getting ID: %x\n", reg0
);
720 apic_write(APIC_ID
, reg0
^ APIC_ID_MASK
);
721 reg1
= apic_read(APIC_ID
);
722 apic_printk(APIC_DEBUG
, "Getting ID: %x\n", reg1
);
723 apic_write(APIC_ID
, reg0
);
724 if (reg1
!= (reg0
^ APIC_ID_MASK
))
728 * The next two are just to see if we have sane values.
729 * They're only really relevant if we're in Virtual Wire
730 * compatibility mode, but most boxes are anymore.
732 reg0
= apic_read(APIC_LVT0
);
733 apic_printk(APIC_DEBUG
, "Getting LVT0: %x\n", reg0
);
734 reg1
= apic_read(APIC_LVT1
);
735 apic_printk(APIC_DEBUG
, "Getting LVT1: %x\n", reg1
);
741 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
743 void __init
sync_Arb_IDs(void)
745 /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 */
752 apic_wait_icr_idle();
754 apic_printk(APIC_DEBUG
, "Synchronizing Arb IDs.\n");
755 apic_write(APIC_ICR
, APIC_DEST_ALLINC
| APIC_INT_LEVELTRIG
760 * An initial setup of the virtual wire mode.
762 void __init
init_bsp_APIC(void)
767 * Don't do the setup now if we have a SMP BIOS as the
768 * through-I/O-APIC virtual wire mode might be active.
770 if (smp_found_config
|| !cpu_has_apic
)
773 value
= apic_read(APIC_LVR
);
776 * Do not trust the local APIC being empty at bootup.
783 value
= apic_read(APIC_SPIV
);
784 value
&= ~APIC_VECTOR_MASK
;
785 value
|= APIC_SPIV_APIC_ENABLED
;
786 value
|= APIC_SPIV_FOCUS_DISABLED
;
787 value
|= SPURIOUS_APIC_VECTOR
;
788 apic_write(APIC_SPIV
, value
);
791 * Set up the virtual wire mode.
793 apic_write(APIC_LVT0
, APIC_DM_EXTINT
);
795 apic_write(APIC_LVT1
, value
);
799 * setup_local_APIC - setup the local APIC
801 void __cpuinit
setup_local_APIC(void)
807 value
= apic_read(APIC_LVR
);
809 BUILD_BUG_ON((SPURIOUS_APIC_VECTOR
& 0x0f) != 0x0f);
812 * Double-check whether this APIC is really registered.
813 * This is meaningless in clustered apic mode, so we skip it.
815 if (!apic_id_registered())
819 * Intel recommends to set DFR, LDR and TPR before enabling
820 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
821 * document number 292116). So here it goes...
826 * Set Task Priority to 'accept all'. We never change this
829 value
= apic_read(APIC_TASKPRI
);
830 value
&= ~APIC_TPRI_MASK
;
831 apic_write(APIC_TASKPRI
, value
);
834 * After a crash, we no longer service the interrupts and a pending
835 * interrupt from previous kernel might still have ISR bit set.
837 * Most probably by now CPU has serviced that pending interrupt and
838 * it might not have done the ack_APIC_irq() because it thought,
839 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
840 * does not clear the ISR bit and cpu thinks it has already serivced
841 * the interrupt. Hence a vector might get locked. It was noticed
842 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
844 for (i
= APIC_ISR_NR
- 1; i
>= 0; i
--) {
845 value
= apic_read(APIC_ISR
+ i
*0x10);
846 for (j
= 31; j
>= 0; j
--) {
853 * Now that we are all set up, enable the APIC
855 value
= apic_read(APIC_SPIV
);
856 value
&= ~APIC_VECTOR_MASK
;
860 value
|= APIC_SPIV_APIC_ENABLED
;
862 /* We always use processor focus */
865 * Set spurious IRQ vector
867 value
|= SPURIOUS_APIC_VECTOR
;
868 apic_write(APIC_SPIV
, value
);
873 * set up through-local-APIC on the BP's LINT0. This is not
874 * strictly necessary in pure symmetric-IO mode, but sometimes
875 * we delegate interrupts to the 8259A.
878 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
880 value
= apic_read(APIC_LVT0
) & APIC_LVT_MASKED
;
881 if (!smp_processor_id() && !value
) {
882 value
= APIC_DM_EXTINT
;
883 apic_printk(APIC_VERBOSE
, "enabled ExtINT on CPU#%d\n",
886 value
= APIC_DM_EXTINT
| APIC_LVT_MASKED
;
887 apic_printk(APIC_VERBOSE
, "masked ExtINT on CPU#%d\n",
890 apic_write(APIC_LVT0
, value
);
893 * only the BP should see the LINT1 NMI signal, obviously.
895 if (!smp_processor_id())
898 value
= APIC_DM_NMI
| APIC_LVT_MASKED
;
899 apic_write(APIC_LVT1
, value
);
903 static void __cpuinit
lapic_setup_esr(void)
905 unsigned maxlvt
= lapic_get_maxlvt();
907 apic_write(APIC_LVTERR
, ERROR_APIC_VECTOR
);
909 * spec says clear errors after enabling vector.
912 apic_write(APIC_ESR
, 0);
915 void __cpuinit
end_local_APIC_setup(void)
918 setup_apic_nmi_watchdog(NULL
);
922 void check_x2apic(void)
926 rdmsr(MSR_IA32_APICBASE
, msr
, msr2
);
928 if (msr
& X2APIC_ENABLE
) {
929 printk("x2apic enabled by BIOS, switching to x2apic ops\n");
930 x2apic_preenabled
= x2apic
= 1;
931 apic_ops
= &x2apic_ops
;
935 void enable_x2apic(void)
939 rdmsr(MSR_IA32_APICBASE
, msr
, msr2
);
940 if (!(msr
& X2APIC_ENABLE
)) {
941 printk("Enabling x2apic\n");
942 wrmsr(MSR_IA32_APICBASE
, msr
| X2APIC_ENABLE
, 0);
946 void enable_IR_x2apic(void)
948 #ifdef CONFIG_INTR_REMAP
955 if (!x2apic_preenabled
&& disable_x2apic
) {
957 "Skipped enabling x2apic and Interrupt-remapping "
958 "because of nox2apic\n");
962 if (x2apic_preenabled
&& disable_x2apic
)
963 panic("Bios already enabled x2apic, can't enforce nox2apic");
965 if (!x2apic_preenabled
&& skip_ioapic_setup
) {
967 "Skipped enabling x2apic and Interrupt-remapping "
968 "because of skipping io-apic setup\n");
972 ret
= dmar_table_init();
975 "dmar_table_init() failed with %d:\n", ret
);
977 if (x2apic_preenabled
)
978 panic("x2apic enabled by bios. But IR enabling failed");
981 "Not enabling x2apic,Intr-remapping\n");
985 local_irq_save(flags
);
987 save_mask_IO_APIC_setup();
989 ret
= enable_intr_remapping(1);
991 if (ret
&& x2apic_preenabled
) {
992 local_irq_restore(flags
);
993 panic("x2apic enabled by bios. But IR enabling failed");
1001 apic_ops
= &x2apic_ops
;
1007 * IR enabling failed
1009 restore_IO_APIC_setup();
1011 reinit_intr_remapped_IO_APIC(x2apic_preenabled
);
1014 local_irq_restore(flags
);
1017 if (!x2apic_preenabled
)
1019 "Enabled x2apic and interrupt-remapping\n");
1022 "Enabled Interrupt-remapping\n");
1025 "Failed to enable Interrupt-remapping and x2apic\n");
1027 if (!cpu_has_x2apic
)
1030 if (x2apic_preenabled
)
1031 panic("x2apic enabled prior OS handover,"
1032 " enable CONFIG_INTR_REMAP");
1034 printk(KERN_INFO
"Enable CONFIG_INTR_REMAP for enabling intr-remapping "
1042 * Detect and enable local APICs on non-SMP boards.
1043 * Original code written by Keir Fraser.
1044 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1045 * not correctly set up (usually the APIC timer won't work etc.)
1047 static int __init
detect_init_APIC(void)
1049 if (!cpu_has_apic
) {
1050 printk(KERN_INFO
"No local APIC present\n");
1054 mp_lapic_addr
= APIC_DEFAULT_PHYS_BASE
;
1055 boot_cpu_physical_apicid
= 0;
1059 void __init
early_init_lapic_mapping(void)
1061 unsigned long phys_addr
;
1064 * If no local APIC can be found then go out
1065 * : it means there is no mpatable and MADT
1067 if (!smp_found_config
)
1070 phys_addr
= mp_lapic_addr
;
1072 set_fixmap_nocache(FIX_APIC_BASE
, phys_addr
);
1073 apic_printk(APIC_VERBOSE
, "mapped APIC to %16lx (%16lx)\n",
1074 APIC_BASE
, phys_addr
);
1077 * Fetch the APIC ID of the BSP in case we have a
1078 * default configuration (or the MP table is broken).
1080 boot_cpu_physical_apicid
= read_apic_id();
1084 * init_apic_mappings - initialize APIC mappings
1086 void __init
init_apic_mappings(void)
1089 boot_cpu_physical_apicid
= read_apic_id();
1094 * If no local APIC can be found then set up a fake all
1095 * zeroes page to simulate the local APIC and another
1096 * one for the IO-APIC.
1098 if (!smp_found_config
&& detect_init_APIC()) {
1099 apic_phys
= (unsigned long) alloc_bootmem_pages(PAGE_SIZE
);
1100 apic_phys
= __pa(apic_phys
);
1102 apic_phys
= mp_lapic_addr
;
1104 set_fixmap_nocache(FIX_APIC_BASE
, apic_phys
);
1105 apic_printk(APIC_VERBOSE
, "mapped APIC to %16lx (%16lx)\n",
1106 APIC_BASE
, apic_phys
);
1109 * Fetch the APIC ID of the BSP in case we have a
1110 * default configuration (or the MP table is broken).
1112 boot_cpu_physical_apicid
= read_apic_id();
1116 * This initializes the IO-APIC and APIC hardware if this is
1119 int __init
APIC_init_uniprocessor(void)
1122 printk(KERN_INFO
"Apic disabled\n");
1125 if (!cpu_has_apic
) {
1127 printk(KERN_INFO
"Apic disabled by BIOS\n");
1132 setup_apic_routing();
1134 verify_local_APIC();
1138 physid_set_mask_of_physid(boot_cpu_physical_apicid
, &phys_cpu_present_map
);
1139 apic_write(APIC_ID
, SET_APIC_ID(boot_cpu_physical_apicid
));
1144 * Now enable IO-APICs, actually call clear_IO_APIC
1145 * We need clear_IO_APIC before enabling vector on BP
1147 if (!skip_ioapic_setup
&& nr_ioapics
)
1150 if (!smp_found_config
|| skip_ioapic_setup
|| !nr_ioapics
)
1151 localise_nmi_watchdog();
1152 end_local_APIC_setup();
1154 if (smp_found_config
&& !skip_ioapic_setup
&& nr_ioapics
)
1158 setup_boot_APIC_clock();
1159 check_nmi_watchdog();
1164 * Local APIC interrupts
1168 * This interrupt should _never_ happen with our APIC/SMP architecture
1170 asmlinkage
void smp_spurious_interrupt(void)
1176 * Check if this really is a spurious interrupt and ACK it
1177 * if it is a vectored one. Just in case...
1178 * Spurious interrupts should not be ACKed.
1180 v
= apic_read(APIC_ISR
+ ((SPURIOUS_APIC_VECTOR
& ~0x1f) >> 1));
1181 if (v
& (1 << (SPURIOUS_APIC_VECTOR
& 0x1f)))
1184 add_pda(irq_spurious_count
, 1);
1189 * This interrupt should never happen with our APIC/SMP architecture
1191 asmlinkage
void smp_error_interrupt(void)
1197 /* First tickle the hardware, only then report what went on. -- REW */
1198 v
= apic_read(APIC_ESR
);
1199 apic_write(APIC_ESR
, 0);
1200 v1
= apic_read(APIC_ESR
);
1202 atomic_inc(&irq_err_count
);
1204 /* Here is what the APIC error bits mean:
1207 2: Send accept error
1208 3: Receive accept error
1210 5: Send illegal vector
1211 6: Received illegal vector
1212 7: Illegal register address
1214 printk(KERN_DEBUG
"APIC error on CPU%d: %02x(%02x)\n",
1215 smp_processor_id(), v
, v1
);
1220 * * connect_bsp_APIC - attach the APIC to the interrupt system
1222 void __init
connect_bsp_APIC(void)
1227 void disconnect_bsp_APIC(int virt_wire_setup
)
1229 /* Go back to Virtual Wire compatibility mode */
1230 unsigned long value
;
1232 /* For the spurious interrupt use vector F, and enable it */
1233 value
= apic_read(APIC_SPIV
);
1234 value
&= ~APIC_VECTOR_MASK
;
1235 value
|= APIC_SPIV_APIC_ENABLED
;
1237 apic_write(APIC_SPIV
, value
);
1239 if (!virt_wire_setup
) {
1241 * For LVT0 make it edge triggered, active high,
1242 * external and enabled
1244 value
= apic_read(APIC_LVT0
);
1245 value
&= ~(APIC_MODE_MASK
| APIC_SEND_PENDING
|
1246 APIC_INPUT_POLARITY
| APIC_LVT_REMOTE_IRR
|
1247 APIC_LVT_LEVEL_TRIGGER
| APIC_LVT_MASKED
);
1248 value
|= APIC_LVT_REMOTE_IRR
| APIC_SEND_PENDING
;
1249 value
= SET_APIC_DELIVERY_MODE(value
, APIC_MODE_EXTINT
);
1250 apic_write(APIC_LVT0
, value
);
1253 apic_write(APIC_LVT0
, APIC_LVT_MASKED
);
1256 /* For LVT1 make it edge triggered, active high, nmi and enabled */
1257 value
= apic_read(APIC_LVT1
);
1258 value
&= ~(APIC_MODE_MASK
| APIC_SEND_PENDING
|
1259 APIC_INPUT_POLARITY
| APIC_LVT_REMOTE_IRR
|
1260 APIC_LVT_LEVEL_TRIGGER
| APIC_LVT_MASKED
);
1261 value
|= APIC_LVT_REMOTE_IRR
| APIC_SEND_PENDING
;
1262 value
= SET_APIC_DELIVERY_MODE(value
, APIC_MODE_NMI
);
1263 apic_write(APIC_LVT1
, value
);
1266 void __cpuinit
generic_processor_info(int apicid
, int version
)
1271 if (num_processors
>= NR_CPUS
) {
1272 printk(KERN_WARNING
"WARNING: NR_CPUS limit of %i reached."
1273 " Processor ignored.\n", NR_CPUS
);
1277 if (num_processors
>= maxcpus
) {
1278 printk(KERN_WARNING
"WARNING: maxcpus limit of %i reached."
1279 " Processor ignored.\n", maxcpus
);
1284 cpus_complement(tmp_map
, cpu_present_map
);
1285 cpu
= first_cpu(tmp_map
);
1287 physid_set(apicid
, phys_cpu_present_map
);
1288 if (apicid
== boot_cpu_physical_apicid
) {
1290 * x86_bios_cpu_apicid is required to have processors listed
1291 * in same order as logical cpu numbers. Hence the first
1292 * entry is BSP, and so on.
1296 if (apicid
> max_physical_apicid
)
1297 max_physical_apicid
= apicid
;
1299 /* are we being called early in kernel startup? */
1300 if (early_per_cpu_ptr(x86_cpu_to_apicid
)) {
1301 u16
*cpu_to_apicid
= early_per_cpu_ptr(x86_cpu_to_apicid
);
1302 u16
*bios_cpu_apicid
= early_per_cpu_ptr(x86_bios_cpu_apicid
);
1304 cpu_to_apicid
[cpu
] = apicid
;
1305 bios_cpu_apicid
[cpu
] = apicid
;
1307 per_cpu(x86_cpu_to_apicid
, cpu
) = apicid
;
1308 per_cpu(x86_bios_cpu_apicid
, cpu
) = apicid
;
1311 cpu_set(cpu
, cpu_possible_map
);
1312 cpu_set(cpu
, cpu_present_map
);
1315 int hard_smp_processor_id(void)
1317 return read_apic_id();
1326 /* 'active' is true if the local APIC was enabled by us and
1327 not the BIOS; this signifies that we are also responsible
1328 for disabling it before entering apm/acpi suspend */
1330 /* r/w apic fields */
1331 unsigned int apic_id
;
1332 unsigned int apic_taskpri
;
1333 unsigned int apic_ldr
;
1334 unsigned int apic_dfr
;
1335 unsigned int apic_spiv
;
1336 unsigned int apic_lvtt
;
1337 unsigned int apic_lvtpc
;
1338 unsigned int apic_lvt0
;
1339 unsigned int apic_lvt1
;
1340 unsigned int apic_lvterr
;
1341 unsigned int apic_tmict
;
1342 unsigned int apic_tdcr
;
1343 unsigned int apic_thmr
;
1346 static int lapic_suspend(struct sys_device
*dev
, pm_message_t state
)
1348 unsigned long flags
;
1351 if (!apic_pm_state
.active
)
1354 maxlvt
= lapic_get_maxlvt();
1356 apic_pm_state
.apic_id
= apic_read(APIC_ID
);
1357 apic_pm_state
.apic_taskpri
= apic_read(APIC_TASKPRI
);
1358 apic_pm_state
.apic_ldr
= apic_read(APIC_LDR
);
1359 apic_pm_state
.apic_dfr
= apic_read(APIC_DFR
);
1360 apic_pm_state
.apic_spiv
= apic_read(APIC_SPIV
);
1361 apic_pm_state
.apic_lvtt
= apic_read(APIC_LVTT
);
1363 apic_pm_state
.apic_lvtpc
= apic_read(APIC_LVTPC
);
1364 apic_pm_state
.apic_lvt0
= apic_read(APIC_LVT0
);
1365 apic_pm_state
.apic_lvt1
= apic_read(APIC_LVT1
);
1366 apic_pm_state
.apic_lvterr
= apic_read(APIC_LVTERR
);
1367 apic_pm_state
.apic_tmict
= apic_read(APIC_TMICT
);
1368 apic_pm_state
.apic_tdcr
= apic_read(APIC_TDCR
);
1369 #ifdef CONFIG_X86_MCE_INTEL
1371 apic_pm_state
.apic_thmr
= apic_read(APIC_LVTTHMR
);
1373 local_irq_save(flags
);
1374 disable_local_APIC();
1375 local_irq_restore(flags
);
1379 static int lapic_resume(struct sys_device
*dev
)
1382 unsigned long flags
;
1385 if (!apic_pm_state
.active
)
1388 maxlvt
= lapic_get_maxlvt();
1390 local_irq_save(flags
);
1392 rdmsr(MSR_IA32_APICBASE
, l
, h
);
1393 l
&= ~MSR_IA32_APICBASE_BASE
;
1394 l
|= MSR_IA32_APICBASE_ENABLE
| mp_lapic_addr
;
1395 wrmsr(MSR_IA32_APICBASE
, l
, h
);
1399 apic_write(APIC_LVTERR
, ERROR_APIC_VECTOR
| APIC_LVT_MASKED
);
1400 apic_write(APIC_ID
, apic_pm_state
.apic_id
);
1401 apic_write(APIC_DFR
, apic_pm_state
.apic_dfr
);
1402 apic_write(APIC_LDR
, apic_pm_state
.apic_ldr
);
1403 apic_write(APIC_TASKPRI
, apic_pm_state
.apic_taskpri
);
1404 apic_write(APIC_SPIV
, apic_pm_state
.apic_spiv
);
1405 apic_write(APIC_LVT0
, apic_pm_state
.apic_lvt0
);
1406 apic_write(APIC_LVT1
, apic_pm_state
.apic_lvt1
);
1407 #ifdef CONFIG_X86_MCE_INTEL
1409 apic_write(APIC_LVTTHMR
, apic_pm_state
.apic_thmr
);
1412 apic_write(APIC_LVTPC
, apic_pm_state
.apic_lvtpc
);
1413 apic_write(APIC_LVTT
, apic_pm_state
.apic_lvtt
);
1414 apic_write(APIC_TDCR
, apic_pm_state
.apic_tdcr
);
1415 apic_write(APIC_TMICT
, apic_pm_state
.apic_tmict
);
1416 apic_write(APIC_ESR
, 0);
1417 apic_read(APIC_ESR
);
1418 apic_write(APIC_LVTERR
, apic_pm_state
.apic_lvterr
);
1419 apic_write(APIC_ESR
, 0);
1420 apic_read(APIC_ESR
);
1421 local_irq_restore(flags
);
1425 static struct sysdev_class lapic_sysclass
= {
1427 .resume
= lapic_resume
,
1428 .suspend
= lapic_suspend
,
1431 static struct sys_device device_lapic
= {
1433 .cls
= &lapic_sysclass
,
1436 static void __cpuinit
apic_pm_activate(void)
1438 apic_pm_state
.active
= 1;
1441 static int __init
init_lapic_sysfs(void)
1447 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
1449 error
= sysdev_class_register(&lapic_sysclass
);
1451 error
= sysdev_register(&device_lapic
);
1454 device_initcall(init_lapic_sysfs
);
1456 #else /* CONFIG_PM */
1458 static void apic_pm_activate(void) { }
1460 #endif /* CONFIG_PM */
1463 * apic_is_clustered_box() -- Check if we can expect good TSC
1465 * Thus far, the major user of this is IBM's Summit2 series:
1467 * Clustered boxes may have unsynced TSC problems if they are
1468 * multi-chassis. Use available data to take a good guess.
1469 * If in doubt, go HPET.
1471 __cpuinit
int apic_is_clustered_box(void)
1473 int i
, clusters
, zeros
;
1475 u16
*bios_cpu_apicid
;
1476 DECLARE_BITMAP(clustermap
, NUM_APIC_CLUSTERS
);
1479 * there is not this kind of box with AMD CPU yet.
1480 * Some AMD box with quadcore cpu and 8 sockets apicid
1481 * will be [4, 0x23] or [8, 0x27] could be thought to
1482 * vsmp box still need checking...
1484 if ((boot_cpu_data
.x86_vendor
== X86_VENDOR_AMD
) && !is_vsmp_box())
1487 bios_cpu_apicid
= early_per_cpu_ptr(x86_bios_cpu_apicid
);
1488 bitmap_zero(clustermap
, NUM_APIC_CLUSTERS
);
1490 for (i
= 0; i
< NR_CPUS
; i
++) {
1491 /* are we being called early in kernel startup? */
1492 if (bios_cpu_apicid
) {
1493 id
= bios_cpu_apicid
[i
];
1495 else if (i
< nr_cpu_ids
) {
1497 id
= per_cpu(x86_bios_cpu_apicid
, i
);
1504 if (id
!= BAD_APICID
)
1505 __set_bit(APIC_CLUSTERID(id
), clustermap
);
1508 /* Problem: Partially populated chassis may not have CPUs in some of
1509 * the APIC clusters they have been allocated. Only present CPUs have
1510 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
1511 * Since clusters are allocated sequentially, count zeros only if
1512 * they are bounded by ones.
1516 for (i
= 0; i
< NUM_APIC_CLUSTERS
; i
++) {
1517 if (test_bit(i
, clustermap
)) {
1518 clusters
+= 1 + zeros
;
1524 /* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
1525 * not guaranteed to be synced between boards
1527 if (is_vsmp_box() && clusters
> 1)
1531 * If clusters > 2, then should be multi-chassis.
1532 * May have to revisit this when multi-core + hyperthreaded CPUs come
1533 * out, but AFAIK this will work even for them.
1535 return (clusters
> 2);
1538 static __init
int setup_nox2apic(char *str
)
1541 clear_cpu_cap(&boot_cpu_data
, X86_FEATURE_X2APIC
);
1544 early_param("nox2apic", setup_nox2apic
);
1548 * APIC command line parameters
1550 static int __init
apic_set_verbosity(char *str
)
1553 skip_ioapic_setup
= 0;
1557 if (strcmp("debug", str
) == 0)
1558 apic_verbosity
= APIC_DEBUG
;
1559 else if (strcmp("verbose", str
) == 0)
1560 apic_verbosity
= APIC_VERBOSE
;
1562 printk(KERN_WARNING
"APIC Verbosity level %s not recognised"
1563 " use apic=verbose or apic=debug\n", str
);
1569 early_param("apic", apic_set_verbosity
);
1571 static __init
int setup_disableapic(char *str
)
1574 setup_clear_cpu_cap(X86_FEATURE_APIC
);
1577 early_param("disableapic", setup_disableapic
);
1579 /* same as disableapic, for compatibility */
1580 static __init
int setup_nolapic(char *str
)
1582 return setup_disableapic(str
);
1584 early_param("nolapic", setup_nolapic
);
1586 static int __init
parse_lapic_timer_c2_ok(char *arg
)
1588 local_apic_timer_c2_ok
= 1;
1591 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok
);
1593 static int __init
parse_disable_apic_timer(char *arg
)
1595 disable_apic_timer
= 1;
1598 early_param("noapictimer", parse_disable_apic_timer
);
1600 static int __init
parse_nolapic_timer(char *arg
)
1602 disable_apic_timer
= 1;
1605 early_param("nolapic_timer", parse_nolapic_timer
);
1607 static __init
int setup_apicpmtimer(char *s
)
1609 apic_calibrate_pmtmr
= 1;
1613 __setup("apicpmtimer", setup_apicpmtimer
);
1615 static int __init
lapic_insert_resource(void)
1620 /* Put local APIC into the resource map. */
1621 lapic_resource
.start
= apic_phys
;
1622 lapic_resource
.end
= lapic_resource
.start
+ PAGE_SIZE
- 1;
1623 insert_resource(&iomem_resource
, &lapic_resource
);
1629 * need call insert after e820_reserve_resources()
1630 * that is using request_resource
1632 late_initcall(lapic_insert_resource
);