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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Local APIC handling, local APIC timers
4 *
5 * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
6 *
7 * Fixes
8 * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
9 * thanks to Eric Gilmore
10 * and Rolf G. Tews
11 * for testing these extensively.
12 * Maciej W. Rozycki : Various updates and fixes.
13 * Mikael Pettersson : Power Management for UP-APIC.
14 * Pavel Machek and
15 * Mikael Pettersson : PM converted to driver model.
16 */
17
18#include <linux/perf_event.h>
19#include <linux/kernel_stat.h>
20#include <linux/mc146818rtc.h>
21#include <linux/acpi_pmtmr.h>
22#include <linux/bitmap.h>
23#include <linux/clockchips.h>
24#include <linux/interrupt.h>
25#include <linux/memblock.h>
26#include <linux/ftrace.h>
27#include <linux/ioport.h>
28#include <linux/export.h>
29#include <linux/syscore_ops.h>
30#include <linux/delay.h>
31#include <linux/timex.h>
32#include <linux/i8253.h>
33#include <linux/dmar.h>
34#include <linux/init.h>
35#include <linux/cpu.h>
36#include <linux/dmi.h>
37#include <linux/smp.h>
38#include <linux/mm.h>
39
40#include <xen/xen.h>
41
42#include <asm/trace/irq_vectors.h>
43#include <asm/irq_remapping.h>
44#include <asm/pc-conf-reg.h>
45#include <asm/perf_event.h>
46#include <asm/x86_init.h>
47#include <linux/atomic.h>
48#include <asm/barrier.h>
49#include <asm/mpspec.h>
50#include <asm/i8259.h>
51#include <asm/proto.h>
52#include <asm/traps.h>
53#include <asm/apic.h>
54#include <asm/acpi.h>
55#include <asm/io_apic.h>
56#include <asm/desc.h>
57#include <asm/hpet.h>
58#include <asm/mtrr.h>
59#include <asm/time.h>
60#include <asm/smp.h>
61#include <asm/mce.h>
62#include <asm/tsc.h>
63#include <asm/hypervisor.h>
64#include <asm/cpu_device_id.h>
65#include <asm/intel-family.h>
66#include <asm/irq_regs.h>
67#include <asm/cpu.h>
68
69#include "local.h"
70
71/* Processor that is doing the boot up */
72u32 boot_cpu_physical_apicid __ro_after_init = BAD_APICID;
73EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
74
75u8 boot_cpu_apic_version __ro_after_init;
76
77/*
78 * This variable controls which CPUs receive external NMIs. By default,
79 * external NMIs are delivered only to the BSP.
80 */
81static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP;
82
83/*
84 * Hypervisor supports 15 bits of APIC ID in MSI Extended Destination ID
85 */
86static bool virt_ext_dest_id __ro_after_init;
87
88/* For parallel bootup. */
89unsigned long apic_mmio_base __ro_after_init;
90
91static inline bool apic_accessible(void)
92{
93 return x2apic_mode || apic_mmio_base;
94}
95
96#ifdef CONFIG_X86_32
97/* Local APIC was disabled by the BIOS and enabled by the kernel */
98static int enabled_via_apicbase __ro_after_init;
99
100/*
101 * Handle interrupt mode configuration register (IMCR).
102 * This register controls whether the interrupt signals
103 * that reach the BSP come from the master PIC or from the
104 * local APIC. Before entering Symmetric I/O Mode, either
105 * the BIOS or the operating system must switch out of
106 * PIC Mode by changing the IMCR.
107 */
108static inline void imcr_pic_to_apic(void)
109{
110 /* NMI and 8259 INTR go through APIC */
111 pc_conf_set(PC_CONF_MPS_IMCR, 0x01);
112}
113
114static inline void imcr_apic_to_pic(void)
115{
116 /* NMI and 8259 INTR go directly to BSP */
117 pc_conf_set(PC_CONF_MPS_IMCR, 0x00);
118}
119#endif
120
121/*
122 * Knob to control our willingness to enable the local APIC.
123 *
124 * +1=force-enable
125 */
126static int force_enable_local_apic __initdata;
127
128/*
129 * APIC command line parameters
130 */
131static int __init parse_lapic(char *arg)
132{
133 if (IS_ENABLED(CONFIG_X86_32) && !arg)
134 force_enable_local_apic = 1;
135 else if (arg && !strncmp(arg, "notscdeadline", 13))
136 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
137 return 0;
138}
139early_param("lapic", parse_lapic);
140
141#ifdef CONFIG_X86_64
142static int apic_calibrate_pmtmr __initdata;
143static __init int setup_apicpmtimer(char *s)
144{
145 apic_calibrate_pmtmr = 1;
146 notsc_setup(NULL);
147 return 1;
148}
149__setup("apicpmtimer", setup_apicpmtimer);
150#endif
151
152static unsigned long mp_lapic_addr __ro_after_init;
153bool apic_is_disabled __ro_after_init;
154/* Disable local APIC timer from the kernel commandline or via dmi quirk */
155static int disable_apic_timer __initdata;
156/* Local APIC timer works in C2 */
157int local_apic_timer_c2_ok __ro_after_init;
158EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
159
160/*
161 * Debug level, exported for io_apic.c
162 */
163int apic_verbosity __ro_after_init;
164
165int pic_mode __ro_after_init;
166
167/* Have we found an MP table */
168int smp_found_config __ro_after_init;
169
170static struct resource lapic_resource = {
171 .name = "Local APIC",
172 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
173};
174
175unsigned int lapic_timer_period = 0;
176
177static void apic_pm_activate(void);
178
179/*
180 * Get the LAPIC version
181 */
182static inline int lapic_get_version(void)
183{
184 return GET_APIC_VERSION(apic_read(APIC_LVR));
185}
186
187/*
188 * Check, if the APIC is integrated or a separate chip
189 */
190static inline int lapic_is_integrated(void)
191{
192 return APIC_INTEGRATED(lapic_get_version());
193}
194
195/*
196 * Check, whether this is a modern or a first generation APIC
197 */
198static int modern_apic(void)
199{
200 /* AMD systems use old APIC versions, so check the CPU */
201 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
202 boot_cpu_data.x86 >= 0xf)
203 return 1;
204
205 /* Hygon systems use modern APIC */
206 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
207 return 1;
208
209 return lapic_get_version() >= 0x14;
210}
211
212/*
213 * right after this call apic become NOOP driven
214 * so apic->write/read doesn't do anything
215 */
216static void __init apic_disable(void)
217{
218 apic_install_driver(&apic_noop);
219}
220
221void native_apic_icr_write(u32 low, u32 id)
222{
223 unsigned long flags;
224
225 local_irq_save(flags);
226 apic_write(APIC_ICR2, SET_XAPIC_DEST_FIELD(id));
227 apic_write(APIC_ICR, low);
228 local_irq_restore(flags);
229}
230
231u64 native_apic_icr_read(void)
232{
233 u32 icr1, icr2;
234
235 icr2 = apic_read(APIC_ICR2);
236 icr1 = apic_read(APIC_ICR);
237
238 return icr1 | ((u64)icr2 << 32);
239}
240
241/**
242 * lapic_get_maxlvt - get the maximum number of local vector table entries
243 */
244int lapic_get_maxlvt(void)
245{
246 /*
247 * - we always have APIC integrated on 64bit mode
248 * - 82489DXs do not report # of LVT entries
249 */
250 return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2;
251}
252
253/*
254 * Local APIC timer
255 */
256
257/* Clock divisor */
258#define APIC_DIVISOR 16
259#define TSC_DIVISOR 8
260
261/* i82489DX specific */
262#define I82489DX_BASE_DIVIDER (((0x2) << 18))
263
264/*
265 * This function sets up the local APIC timer, with a timeout of
266 * 'clocks' APIC bus clock. During calibration we actually call
267 * this function twice on the boot CPU, once with a bogus timeout
268 * value, second time for real. The other (noncalibrating) CPUs
269 * call this function only once, with the real, calibrated value.
270 *
271 * We do reads before writes even if unnecessary, to get around the
272 * P5 APIC double write bug.
273 */
274static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
275{
276 unsigned int lvtt_value, tmp_value;
277
278 lvtt_value = LOCAL_TIMER_VECTOR;
279 if (!oneshot)
280 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
281 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
282 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
283
284 /*
285 * The i82489DX APIC uses bit 18 and 19 for the base divider. This
286 * overlaps with bit 18 on integrated APICs, but is not documented
287 * in the SDM. No problem though. i82489DX equipped systems do not
288 * have TSC deadline timer.
289 */
290 if (!lapic_is_integrated())
291 lvtt_value |= I82489DX_BASE_DIVIDER;
292
293 if (!irqen)
294 lvtt_value |= APIC_LVT_MASKED;
295
296 apic_write(APIC_LVTT, lvtt_value);
297
298 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
299 /*
300 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
301 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
302 * According to Intel, MFENCE can do the serialization here.
303 */
304 asm volatile("mfence" : : : "memory");
305 return;
306 }
307
308 /*
309 * Divide PICLK by 16
310 */
311 tmp_value = apic_read(APIC_TDCR);
312 apic_write(APIC_TDCR,
313 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
314 APIC_TDR_DIV_16);
315
316 if (!oneshot)
317 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
318}
319
320/*
321 * Setup extended LVT, AMD specific
322 *
323 * Software should use the LVT offsets the BIOS provides. The offsets
324 * are determined by the subsystems using it like those for MCE
325 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
326 * are supported. Beginning with family 10h at least 4 offsets are
327 * available.
328 *
329 * Since the offsets must be consistent for all cores, we keep track
330 * of the LVT offsets in software and reserve the offset for the same
331 * vector also to be used on other cores. An offset is freed by
332 * setting the entry to APIC_EILVT_MASKED.
333 *
334 * If the BIOS is right, there should be no conflicts. Otherwise a
335 * "[Firmware Bug]: ..." error message is generated. However, if
336 * software does not properly determines the offsets, it is not
337 * necessarily a BIOS bug.
338 */
339
340static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
341
342static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
343{
344 return (old & APIC_EILVT_MASKED)
345 || (new == APIC_EILVT_MASKED)
346 || ((new & ~APIC_EILVT_MASKED) == old);
347}
348
349static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
350{
351 unsigned int rsvd, vector;
352
353 if (offset >= APIC_EILVT_NR_MAX)
354 return ~0;
355
356 rsvd = atomic_read(&eilvt_offsets[offset]);
357 do {
358 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
359 if (vector && !eilvt_entry_is_changeable(vector, new))
360 /* may not change if vectors are different */
361 return rsvd;
362 } while (!atomic_try_cmpxchg(&eilvt_offsets[offset], &rsvd, new));
363
364 rsvd = new & ~APIC_EILVT_MASKED;
365 if (rsvd && rsvd != vector)
366 pr_info("LVT offset %d assigned for vector 0x%02x\n",
367 offset, rsvd);
368
369 return new;
370}
371
372/*
373 * If mask=1, the LVT entry does not generate interrupts while mask=0
374 * enables the vector. See also the BKDGs. Must be called with
375 * preemption disabled.
376 */
377
378int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
379{
380 unsigned long reg = APIC_EILVTn(offset);
381 unsigned int new, old, reserved;
382
383 new = (mask << 16) | (msg_type << 8) | vector;
384 old = apic_read(reg);
385 reserved = reserve_eilvt_offset(offset, new);
386
387 if (reserved != new) {
388 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
389 "vector 0x%x, but the register is already in use for "
390 "vector 0x%x on another cpu\n",
391 smp_processor_id(), reg, offset, new, reserved);
392 return -EINVAL;
393 }
394
395 if (!eilvt_entry_is_changeable(old, new)) {
396 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
397 "vector 0x%x, but the register is already in use for "
398 "vector 0x%x on this cpu\n",
399 smp_processor_id(), reg, offset, new, old);
400 return -EBUSY;
401 }
402
403 apic_write(reg, new);
404
405 return 0;
406}
407EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
408
409/*
410 * Program the next event, relative to now
411 */
412static int lapic_next_event(unsigned long delta,
413 struct clock_event_device *evt)
414{
415 apic_write(APIC_TMICT, delta);
416 return 0;
417}
418
419static int lapic_next_deadline(unsigned long delta,
420 struct clock_event_device *evt)
421{
422 u64 tsc;
423
424 /* This MSR is special and need a special fence: */
425 weak_wrmsr_fence();
426
427 tsc = rdtsc();
428 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
429 return 0;
430}
431
432static int lapic_timer_shutdown(struct clock_event_device *evt)
433{
434 unsigned int v;
435
436 /* Lapic used as dummy for broadcast ? */
437 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
438 return 0;
439
440 v = apic_read(APIC_LVTT);
441 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
442 apic_write(APIC_LVTT, v);
443
444 /*
445 * Setting APIC_LVT_MASKED (above) should be enough to tell
446 * the hardware that this timer will never fire. But AMD
447 * erratum 411 and some Intel CPU behavior circa 2024 say
448 * otherwise. Time for belt and suspenders programming: mask
449 * the timer _and_ zero the counter registers:
450 */
451 if (v & APIC_LVT_TIMER_TSCDEADLINE)
452 wrmsrl(MSR_IA32_TSC_DEADLINE, 0);
453 else
454 apic_write(APIC_TMICT, 0);
455
456 return 0;
457}
458
459static inline int
460lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
461{
462 /* Lapic used as dummy for broadcast ? */
463 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
464 return 0;
465
466 __setup_APIC_LVTT(lapic_timer_period, oneshot, 1);
467 return 0;
468}
469
470static int lapic_timer_set_periodic(struct clock_event_device *evt)
471{
472 return lapic_timer_set_periodic_oneshot(evt, false);
473}
474
475static int lapic_timer_set_oneshot(struct clock_event_device *evt)
476{
477 return lapic_timer_set_periodic_oneshot(evt, true);
478}
479
480/*
481 * Local APIC timer broadcast function
482 */
483static void lapic_timer_broadcast(const struct cpumask *mask)
484{
485#ifdef CONFIG_SMP
486 __apic_send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
487#endif
488}
489
490
491/*
492 * The local apic timer can be used for any function which is CPU local.
493 */
494static struct clock_event_device lapic_clockevent = {
495 .name = "lapic",
496 .features = CLOCK_EVT_FEAT_PERIODIC |
497 CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
498 | CLOCK_EVT_FEAT_DUMMY,
499 .shift = 32,
500 .set_state_shutdown = lapic_timer_shutdown,
501 .set_state_periodic = lapic_timer_set_periodic,
502 .set_state_oneshot = lapic_timer_set_oneshot,
503 .set_state_oneshot_stopped = lapic_timer_shutdown,
504 .set_next_event = lapic_next_event,
505 .broadcast = lapic_timer_broadcast,
506 .rating = 100,
507 .irq = -1,
508};
509static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
510
511static const struct x86_cpu_id deadline_match[] __initconst = {
512 X86_MATCH_VFM_STEPPINGS(INTEL_HASWELL_X, X86_STEPPINGS(0x2, 0x2), 0x3a), /* EP */
513 X86_MATCH_VFM_STEPPINGS(INTEL_HASWELL_X, X86_STEPPINGS(0x4, 0x4), 0x0f), /* EX */
514
515 X86_MATCH_VFM(INTEL_BROADWELL_X, 0x0b000020),
516
517 X86_MATCH_VFM_STEPPINGS(INTEL_BROADWELL_D, X86_STEPPINGS(0x2, 0x2), 0x00000011),
518 X86_MATCH_VFM_STEPPINGS(INTEL_BROADWELL_D, X86_STEPPINGS(0x3, 0x3), 0x0700000e),
519 X86_MATCH_VFM_STEPPINGS(INTEL_BROADWELL_D, X86_STEPPINGS(0x4, 0x4), 0x0f00000c),
520 X86_MATCH_VFM_STEPPINGS(INTEL_BROADWELL_D, X86_STEPPINGS(0x5, 0x5), 0x0e000003),
521
522 X86_MATCH_VFM_STEPPINGS(INTEL_SKYLAKE_X, X86_STEPPINGS(0x3, 0x3), 0x01000136),
523 X86_MATCH_VFM_STEPPINGS(INTEL_SKYLAKE_X, X86_STEPPINGS(0x4, 0x4), 0x02000014),
524 X86_MATCH_VFM_STEPPINGS(INTEL_SKYLAKE_X, X86_STEPPINGS(0x5, 0xf), 0),
525
526 X86_MATCH_VFM(INTEL_HASWELL, 0x22),
527 X86_MATCH_VFM(INTEL_HASWELL_L, 0x20),
528 X86_MATCH_VFM(INTEL_HASWELL_G, 0x17),
529
530 X86_MATCH_VFM(INTEL_BROADWELL, 0x25),
531 X86_MATCH_VFM(INTEL_BROADWELL_G, 0x17),
532
533 X86_MATCH_VFM(INTEL_SKYLAKE_L, 0xb2),
534 X86_MATCH_VFM(INTEL_SKYLAKE, 0xb2),
535
536 X86_MATCH_VFM(INTEL_KABYLAKE_L, 0x52),
537 X86_MATCH_VFM(INTEL_KABYLAKE, 0x52),
538
539 {},
540};
541
542static __init bool apic_validate_deadline_timer(void)
543{
544 const struct x86_cpu_id *m;
545 u32 rev;
546
547 if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
548 return false;
549 if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
550 return true;
551
552 m = x86_match_cpu(deadline_match);
553 if (!m)
554 return true;
555
556 rev = (u32)m->driver_data;
557
558 if (boot_cpu_data.microcode >= rev)
559 return true;
560
561 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
562 pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; "
563 "please update microcode to version: 0x%x (or later)\n", rev);
564 return false;
565}
566
567/*
568 * Setup the local APIC timer for this CPU. Copy the initialized values
569 * of the boot CPU and register the clock event in the framework.
570 */
571static void setup_APIC_timer(void)
572{
573 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
574
575 if (this_cpu_has(X86_FEATURE_ARAT)) {
576 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
577 /* Make LAPIC timer preferable over percpu HPET */
578 lapic_clockevent.rating = 150;
579 }
580
581 memcpy(levt, &lapic_clockevent, sizeof(*levt));
582 levt->cpumask = cpumask_of(smp_processor_id());
583
584 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
585 levt->name = "lapic-deadline";
586 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
587 CLOCK_EVT_FEAT_DUMMY);
588 levt->set_next_event = lapic_next_deadline;
589 clockevents_config_and_register(levt,
590 tsc_khz * (1000 / TSC_DIVISOR),
591 0xF, ~0UL);
592 } else
593 clockevents_register_device(levt);
594}
595
596/*
597 * Install the updated TSC frequency from recalibration at the TSC
598 * deadline clockevent devices.
599 */
600static void __lapic_update_tsc_freq(void *info)
601{
602 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
603
604 if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
605 return;
606
607 clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
608}
609
610void lapic_update_tsc_freq(void)
611{
612 /*
613 * The clockevent device's ->mult and ->shift can both be
614 * changed. In order to avoid races, schedule the frequency
615 * update code on each CPU.
616 */
617 on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
618}
619
620/*
621 * In this functions we calibrate APIC bus clocks to the external timer.
622 *
623 * We want to do the calibration only once since we want to have local timer
624 * irqs synchronous. CPUs connected by the same APIC bus have the very same bus
625 * frequency.
626 *
627 * This was previously done by reading the PIT/HPET and waiting for a wrap
628 * around to find out, that a tick has elapsed. I have a box, where the PIT
629 * readout is broken, so it never gets out of the wait loop again. This was
630 * also reported by others.
631 *
632 * Monitoring the jiffies value is inaccurate and the clockevents
633 * infrastructure allows us to do a simple substitution of the interrupt
634 * handler.
635 *
636 * The calibration routine also uses the pm_timer when possible, as the PIT
637 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
638 * back to normal later in the boot process).
639 */
640
641#define LAPIC_CAL_LOOPS (HZ/10)
642
643static __initdata int lapic_cal_loops = -1;
644static __initdata long lapic_cal_t1, lapic_cal_t2;
645static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
646static __initdata u32 lapic_cal_pm1, lapic_cal_pm2;
647static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
648
649/*
650 * Temporary interrupt handler and polled calibration function.
651 */
652static void __init lapic_cal_handler(struct clock_event_device *dev)
653{
654 unsigned long long tsc = 0;
655 long tapic = apic_read(APIC_TMCCT);
656 u32 pm = acpi_pm_read_early();
657
658 if (boot_cpu_has(X86_FEATURE_TSC))
659 tsc = rdtsc();
660
661 switch (lapic_cal_loops++) {
662 case 0:
663 lapic_cal_t1 = tapic;
664 lapic_cal_tsc1 = tsc;
665 lapic_cal_pm1 = pm;
666 lapic_cal_j1 = jiffies;
667 break;
668
669 case LAPIC_CAL_LOOPS:
670 lapic_cal_t2 = tapic;
671 lapic_cal_tsc2 = tsc;
672 if (pm < lapic_cal_pm1)
673 pm += ACPI_PM_OVRRUN;
674 lapic_cal_pm2 = pm;
675 lapic_cal_j2 = jiffies;
676 break;
677 }
678}
679
680static int __init
681calibrate_by_pmtimer(u32 deltapm, long *delta, long *deltatsc)
682{
683 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
684 const long pm_thresh = pm_100ms / 100;
685 unsigned long mult;
686 u64 res;
687
688#ifndef CONFIG_X86_PM_TIMER
689 return -1;
690#endif
691
692 apic_pr_verbose("... PM-Timer delta = %u\n", deltapm);
693
694 /* Check, if the PM timer is available */
695 if (!deltapm)
696 return -1;
697
698 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
699
700 if (deltapm > (pm_100ms - pm_thresh) &&
701 deltapm < (pm_100ms + pm_thresh)) {
702 apic_pr_verbose("... PM-Timer result ok\n");
703 return 0;
704 }
705
706 res = (((u64)deltapm) * mult) >> 22;
707 do_div(res, 1000000);
708 pr_warn("APIC calibration not consistent with PM-Timer: %ldms instead of 100ms\n",
709 (long)res);
710
711 /* Correct the lapic counter value */
712 res = (((u64)(*delta)) * pm_100ms);
713 do_div(res, deltapm);
714 pr_info("APIC delta adjusted to PM-Timer: "
715 "%lu (%ld)\n", (unsigned long)res, *delta);
716 *delta = (long)res;
717
718 /* Correct the tsc counter value */
719 if (boot_cpu_has(X86_FEATURE_TSC)) {
720 res = (((u64)(*deltatsc)) * pm_100ms);
721 do_div(res, deltapm);
722 apic_pr_verbose("TSC delta adjusted to PM-Timer: %lu (%ld)\n",
723 (unsigned long)res, *deltatsc);
724 *deltatsc = (long)res;
725 }
726
727 return 0;
728}
729
730static int __init lapic_init_clockevent(void)
731{
732 if (!lapic_timer_period)
733 return -1;
734
735 /* Calculate the scaled math multiplication factor */
736 lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR,
737 TICK_NSEC, lapic_clockevent.shift);
738 lapic_clockevent.max_delta_ns =
739 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
740 lapic_clockevent.max_delta_ticks = 0x7FFFFFFF;
741 lapic_clockevent.min_delta_ns =
742 clockevent_delta2ns(0xF, &lapic_clockevent);
743 lapic_clockevent.min_delta_ticks = 0xF;
744
745 return 0;
746}
747
748bool __init apic_needs_pit(void)
749{
750 /*
751 * If the frequencies are not known, PIT is required for both TSC
752 * and apic timer calibration.
753 */
754 if (!tsc_khz || !cpu_khz)
755 return true;
756
757 /* Is there an APIC at all or is it disabled? */
758 if (!boot_cpu_has(X86_FEATURE_APIC) || apic_is_disabled)
759 return true;
760
761 /*
762 * If interrupt delivery mode is legacy PIC or virtual wire without
763 * configuration, the local APIC timer won't be set up. Make sure
764 * that the PIT is initialized.
765 */
766 if (apic_intr_mode == APIC_PIC ||
767 apic_intr_mode == APIC_VIRTUAL_WIRE_NO_CONFIG)
768 return true;
769
770 /* Virt guests may lack ARAT, but still have DEADLINE */
771 if (!boot_cpu_has(X86_FEATURE_ARAT))
772 return true;
773
774 /* Deadline timer is based on TSC so no further PIT action required */
775 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
776 return false;
777
778 /* APIC timer disabled? */
779 if (disable_apic_timer)
780 return true;
781 /*
782 * The APIC timer frequency is known already, no PIT calibration
783 * required. If unknown, let the PIT be initialized.
784 */
785 return lapic_timer_period == 0;
786}
787
788static int __init calibrate_APIC_clock(void)
789{
790 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
791 u64 tsc_perj = 0, tsc_start = 0;
792 unsigned long jif_start;
793 unsigned long deltaj;
794 long delta, deltatsc;
795 int pm_referenced = 0;
796
797 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
798 return 0;
799
800 /*
801 * Check if lapic timer has already been calibrated by platform
802 * specific routine, such as tsc calibration code. If so just fill
803 * in the clockevent structure and return.
804 */
805 if (!lapic_init_clockevent()) {
806 apic_pr_verbose("lapic timer already calibrated %d\n", lapic_timer_period);
807 /*
808 * Direct calibration methods must have an always running
809 * local APIC timer, no need for broadcast timer.
810 */
811 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
812 return 0;
813 }
814
815 apic_pr_verbose("Using local APIC timer interrupts. Calibrating APIC timer ...\n");
816
817 /*
818 * There are platforms w/o global clockevent devices. Instead of
819 * making the calibration conditional on that, use a polling based
820 * approach everywhere.
821 */
822 local_irq_disable();
823
824 /*
825 * Setup the APIC counter to maximum. There is no way the lapic
826 * can underflow in the 100ms detection time frame
827 */
828 __setup_APIC_LVTT(0xffffffff, 0, 0);
829
830 /*
831 * Methods to terminate the calibration loop:
832 * 1) Global clockevent if available (jiffies)
833 * 2) TSC if available and frequency is known
834 */
835 jif_start = READ_ONCE(jiffies);
836
837 if (tsc_khz) {
838 tsc_start = rdtsc();
839 tsc_perj = div_u64((u64)tsc_khz * 1000, HZ);
840 }
841
842 /*
843 * Enable interrupts so the tick can fire, if a global
844 * clockevent device is available
845 */
846 local_irq_enable();
847
848 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) {
849 /* Wait for a tick to elapse */
850 while (1) {
851 if (tsc_khz) {
852 u64 tsc_now = rdtsc();
853 if ((tsc_now - tsc_start) >= tsc_perj) {
854 tsc_start += tsc_perj;
855 break;
856 }
857 } else {
858 unsigned long jif_now = READ_ONCE(jiffies);
859
860 if (time_after(jif_now, jif_start)) {
861 jif_start = jif_now;
862 break;
863 }
864 }
865 cpu_relax();
866 }
867
868 /* Invoke the calibration routine */
869 local_irq_disable();
870 lapic_cal_handler(NULL);
871 local_irq_enable();
872 }
873
874 local_irq_disable();
875
876 /* Build delta t1-t2 as apic timer counts down */
877 delta = lapic_cal_t1 - lapic_cal_t2;
878 apic_pr_verbose("... lapic delta = %ld\n", delta);
879
880 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
881
882 /* we trust the PM based calibration if possible */
883 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
884 &delta, &deltatsc);
885
886 lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
887 lapic_init_clockevent();
888
889 apic_pr_verbose("..... delta %ld\n", delta);
890 apic_pr_verbose("..... mult: %u\n", lapic_clockevent.mult);
891 apic_pr_verbose("..... calibration result: %u\n", lapic_timer_period);
892
893 if (boot_cpu_has(X86_FEATURE_TSC)) {
894 apic_pr_verbose("..... CPU clock speed is %ld.%04ld MHz.\n",
895 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
896 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
897 }
898
899 apic_pr_verbose("..... host bus clock speed is %u.%04u MHz.\n",
900 lapic_timer_period / (1000000 / HZ),
901 lapic_timer_period % (1000000 / HZ));
902
903 /*
904 * Do a sanity check on the APIC calibration result
905 */
906 if (lapic_timer_period < (1000000 / HZ)) {
907 local_irq_enable();
908 pr_warn("APIC frequency too slow, disabling apic timer\n");
909 return -1;
910 }
911
912 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
913
914 /*
915 * PM timer calibration failed or not turned on so lets try APIC
916 * timer based calibration, if a global clockevent device is
917 * available.
918 */
919 if (!pm_referenced && global_clock_event) {
920 apic_pr_verbose("... verify APIC timer\n");
921
922 /*
923 * Setup the apic timer manually
924 */
925 levt->event_handler = lapic_cal_handler;
926 lapic_timer_set_periodic(levt);
927 lapic_cal_loops = -1;
928
929 /* Let the interrupts run */
930 local_irq_enable();
931
932 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
933 cpu_relax();
934
935 /* Stop the lapic timer */
936 local_irq_disable();
937 lapic_timer_shutdown(levt);
938
939 /* Jiffies delta */
940 deltaj = lapic_cal_j2 - lapic_cal_j1;
941 apic_pr_verbose("... jiffies delta = %lu\n", deltaj);
942
943 /* Check, if the jiffies result is consistent */
944 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
945 apic_pr_verbose("... jiffies result ok\n");
946 else
947 levt->features |= CLOCK_EVT_FEAT_DUMMY;
948 }
949 local_irq_enable();
950
951 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
952 pr_warn("APIC timer disabled due to verification failure\n");
953 return -1;
954 }
955
956 return 0;
957}
958
959/*
960 * Setup the boot APIC
961 *
962 * Calibrate and verify the result.
963 */
964void __init setup_boot_APIC_clock(void)
965{
966 /*
967 * The local apic timer can be disabled via the kernel
968 * commandline or from the CPU detection code. Register the lapic
969 * timer as a dummy clock event source on SMP systems, so the
970 * broadcast mechanism is used. On UP systems simply ignore it.
971 */
972 if (disable_apic_timer) {
973 pr_info("Disabling APIC timer\n");
974 /* No broadcast on UP ! */
975 if (num_possible_cpus() > 1) {
976 lapic_clockevent.mult = 1;
977 setup_APIC_timer();
978 }
979 return;
980 }
981
982 if (calibrate_APIC_clock()) {
983 /* No broadcast on UP ! */
984 if (num_possible_cpus() > 1)
985 setup_APIC_timer();
986 return;
987 }
988
989 /*
990 * If nmi_watchdog is set to IO_APIC, we need the
991 * PIT/HPET going. Otherwise register lapic as a dummy
992 * device.
993 */
994 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
995
996 /* Setup the lapic or request the broadcast */
997 setup_APIC_timer();
998 amd_e400_c1e_apic_setup();
999}
1000
1001void setup_secondary_APIC_clock(void)
1002{
1003 setup_APIC_timer();
1004 amd_e400_c1e_apic_setup();
1005}
1006
1007/*
1008 * The guts of the apic timer interrupt
1009 */
1010static void local_apic_timer_interrupt(void)
1011{
1012 struct clock_event_device *evt = this_cpu_ptr(&lapic_events);
1013
1014 /*
1015 * Normally we should not be here till LAPIC has been initialized but
1016 * in some cases like kdump, its possible that there is a pending LAPIC
1017 * timer interrupt from previous kernel's context and is delivered in
1018 * new kernel the moment interrupts are enabled.
1019 *
1020 * Interrupts are enabled early and LAPIC is setup much later, hence
1021 * its possible that when we get here evt->event_handler is NULL.
1022 * Check for event_handler being NULL and discard the interrupt as
1023 * spurious.
1024 */
1025 if (!evt->event_handler) {
1026 pr_warn("Spurious LAPIC timer interrupt on cpu %d\n",
1027 smp_processor_id());
1028 /* Switch it off */
1029 lapic_timer_shutdown(evt);
1030 return;
1031 }
1032
1033 /*
1034 * the NMI deadlock-detector uses this.
1035 */
1036 inc_irq_stat(apic_timer_irqs);
1037
1038 evt->event_handler(evt);
1039}
1040
1041/*
1042 * Local APIC timer interrupt. This is the most natural way for doing
1043 * local interrupts, but local timer interrupts can be emulated by
1044 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
1045 *
1046 * [ if a single-CPU system runs an SMP kernel then we call the local
1047 * interrupt as well. Thus we cannot inline the local irq ... ]
1048 */
1049DEFINE_IDTENTRY_SYSVEC(sysvec_apic_timer_interrupt)
1050{
1051 struct pt_regs *old_regs = set_irq_regs(regs);
1052
1053 apic_eoi();
1054 trace_local_timer_entry(LOCAL_TIMER_VECTOR);
1055 local_apic_timer_interrupt();
1056 trace_local_timer_exit(LOCAL_TIMER_VECTOR);
1057
1058 set_irq_regs(old_regs);
1059}
1060
1061/*
1062 * Local APIC start and shutdown
1063 */
1064
1065/**
1066 * clear_local_APIC - shutdown the local APIC
1067 *
1068 * This is called, when a CPU is disabled and before rebooting, so the state of
1069 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
1070 * leftovers during boot.
1071 */
1072void clear_local_APIC(void)
1073{
1074 int maxlvt;
1075 u32 v;
1076
1077 if (!apic_accessible())
1078 return;
1079
1080 maxlvt = lapic_get_maxlvt();
1081 /*
1082 * Masking an LVT entry can trigger a local APIC error
1083 * if the vector is zero. Mask LVTERR first to prevent this.
1084 */
1085 if (maxlvt >= 3) {
1086 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
1087 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
1088 }
1089 /*
1090 * Careful: we have to set masks only first to deassert
1091 * any level-triggered sources.
1092 */
1093 v = apic_read(APIC_LVTT);
1094 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
1095 v = apic_read(APIC_LVT0);
1096 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1097 v = apic_read(APIC_LVT1);
1098 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1099 if (maxlvt >= 4) {
1100 v = apic_read(APIC_LVTPC);
1101 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1102 }
1103
1104 /* lets not touch this if we didn't frob it */
1105#ifdef CONFIG_X86_THERMAL_VECTOR
1106 if (maxlvt >= 5) {
1107 v = apic_read(APIC_LVTTHMR);
1108 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1109 }
1110#endif
1111#ifdef CONFIG_X86_MCE_INTEL
1112 if (maxlvt >= 6) {
1113 v = apic_read(APIC_LVTCMCI);
1114 if (!(v & APIC_LVT_MASKED))
1115 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1116 }
1117#endif
1118
1119 /*
1120 * Clean APIC state for other OSs:
1121 */
1122 apic_write(APIC_LVTT, APIC_LVT_MASKED);
1123 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1124 apic_write(APIC_LVT1, APIC_LVT_MASKED);
1125 if (maxlvt >= 3)
1126 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1127 if (maxlvt >= 4)
1128 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1129
1130 /* Integrated APIC (!82489DX) ? */
1131 if (lapic_is_integrated()) {
1132 if (maxlvt > 3)
1133 /* Clear ESR due to Pentium errata 3AP and 11AP */
1134 apic_write(APIC_ESR, 0);
1135 apic_read(APIC_ESR);
1136 }
1137}
1138
1139/**
1140 * apic_soft_disable - Clears and software disables the local APIC on hotplug
1141 *
1142 * Contrary to disable_local_APIC() this does not touch the enable bit in
1143 * MSR_IA32_APICBASE. Clearing that bit on systems based on the 3 wire APIC
1144 * bus would require a hardware reset as the APIC would lose track of bus
1145 * arbitration. On systems with FSB delivery APICBASE could be disabled,
1146 * but it has to be guaranteed that no interrupt is sent to the APIC while
1147 * in that state and it's not clear from the SDM whether it still responds
1148 * to INIT/SIPI messages. Stay on the safe side and use software disable.
1149 */
1150void apic_soft_disable(void)
1151{
1152 u32 value;
1153
1154 clear_local_APIC();
1155
1156 /* Soft disable APIC (implies clearing of registers for 82489DX!). */
1157 value = apic_read(APIC_SPIV);
1158 value &= ~APIC_SPIV_APIC_ENABLED;
1159 apic_write(APIC_SPIV, value);
1160}
1161
1162/**
1163 * disable_local_APIC - clear and disable the local APIC
1164 */
1165void disable_local_APIC(void)
1166{
1167 if (!apic_accessible())
1168 return;
1169
1170 apic_soft_disable();
1171
1172#ifdef CONFIG_X86_32
1173 /*
1174 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1175 * restore the disabled state.
1176 */
1177 if (enabled_via_apicbase) {
1178 unsigned int l, h;
1179
1180 rdmsr(MSR_IA32_APICBASE, l, h);
1181 l &= ~MSR_IA32_APICBASE_ENABLE;
1182 wrmsr(MSR_IA32_APICBASE, l, h);
1183 }
1184#endif
1185}
1186
1187/*
1188 * If Linux enabled the LAPIC against the BIOS default disable it down before
1189 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
1190 * not power-off. Additionally clear all LVT entries before disable_local_APIC
1191 * for the case where Linux didn't enable the LAPIC.
1192 */
1193void lapic_shutdown(void)
1194{
1195 unsigned long flags;
1196
1197 if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
1198 return;
1199
1200 local_irq_save(flags);
1201
1202#ifdef CONFIG_X86_32
1203 if (!enabled_via_apicbase)
1204 clear_local_APIC();
1205 else
1206#endif
1207 disable_local_APIC();
1208
1209
1210 local_irq_restore(flags);
1211}
1212
1213/**
1214 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1215 */
1216void __init sync_Arb_IDs(void)
1217{
1218 /*
1219 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1220 * needed on AMD.
1221 */
1222 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1223 return;
1224
1225 /*
1226 * Wait for idle.
1227 */
1228 apic_wait_icr_idle();
1229
1230 apic_pr_debug("Synchronizing Arb IDs.\n");
1231 apic_write(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG | APIC_DM_INIT);
1232}
1233
1234enum apic_intr_mode_id apic_intr_mode __ro_after_init;
1235
1236static int __init __apic_intr_mode_select(void)
1237{
1238 /* Check kernel option */
1239 if (apic_is_disabled) {
1240 pr_info("APIC disabled via kernel command line\n");
1241 return APIC_PIC;
1242 }
1243
1244 /* Check BIOS */
1245#ifdef CONFIG_X86_64
1246 /* On 64-bit, the APIC must be integrated, Check local APIC only */
1247 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1248 apic_is_disabled = true;
1249 pr_info("APIC disabled by BIOS\n");
1250 return APIC_PIC;
1251 }
1252#else
1253 /* On 32-bit, the APIC may be integrated APIC or 82489DX */
1254
1255 /* Neither 82489DX nor integrated APIC ? */
1256 if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) {
1257 apic_is_disabled = true;
1258 return APIC_PIC;
1259 }
1260
1261 /* If the BIOS pretends there is an integrated APIC ? */
1262 if (!boot_cpu_has(X86_FEATURE_APIC) &&
1263 APIC_INTEGRATED(boot_cpu_apic_version)) {
1264 apic_is_disabled = true;
1265 pr_err(FW_BUG "Local APIC not detected, force emulation\n");
1266 return APIC_PIC;
1267 }
1268#endif
1269
1270 /* Check MP table or ACPI MADT configuration */
1271 if (!smp_found_config) {
1272 disable_ioapic_support();
1273 if (!acpi_lapic) {
1274 pr_info("APIC: ACPI MADT or MP tables are not detected\n");
1275 return APIC_VIRTUAL_WIRE_NO_CONFIG;
1276 }
1277 return APIC_VIRTUAL_WIRE;
1278 }
1279
1280#ifdef CONFIG_SMP
1281 /* If SMP should be disabled, then really disable it! */
1282 if (!setup_max_cpus) {
1283 pr_info("APIC: SMP mode deactivated\n");
1284 return APIC_SYMMETRIC_IO_NO_ROUTING;
1285 }
1286#endif
1287
1288 return APIC_SYMMETRIC_IO;
1289}
1290
1291/* Select the interrupt delivery mode for the BSP */
1292void __init apic_intr_mode_select(void)
1293{
1294 apic_intr_mode = __apic_intr_mode_select();
1295}
1296
1297/*
1298 * An initial setup of the virtual wire mode.
1299 */
1300void __init init_bsp_APIC(void)
1301{
1302 unsigned int value;
1303
1304 /*
1305 * Don't do the setup now if we have a SMP BIOS as the
1306 * through-I/O-APIC virtual wire mode might be active.
1307 */
1308 if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
1309 return;
1310
1311 /*
1312 * Do not trust the local APIC being empty at bootup.
1313 */
1314 clear_local_APIC();
1315
1316 /*
1317 * Enable APIC.
1318 */
1319 value = apic_read(APIC_SPIV);
1320 value &= ~APIC_VECTOR_MASK;
1321 value |= APIC_SPIV_APIC_ENABLED;
1322
1323#ifdef CONFIG_X86_32
1324 /* This bit is reserved on P4/Xeon and should be cleared */
1325 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1326 (boot_cpu_data.x86 == 15))
1327 value &= ~APIC_SPIV_FOCUS_DISABLED;
1328 else
1329#endif
1330 value |= APIC_SPIV_FOCUS_DISABLED;
1331 value |= SPURIOUS_APIC_VECTOR;
1332 apic_write(APIC_SPIV, value);
1333
1334 /*
1335 * Set up the virtual wire mode.
1336 */
1337 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1338 value = APIC_DM_NMI;
1339 if (!lapic_is_integrated()) /* 82489DX */
1340 value |= APIC_LVT_LEVEL_TRIGGER;
1341 if (apic_extnmi == APIC_EXTNMI_NONE)
1342 value |= APIC_LVT_MASKED;
1343 apic_write(APIC_LVT1, value);
1344}
1345
1346static void __init apic_bsp_setup(bool upmode);
1347
1348/* Init the interrupt delivery mode for the BSP */
1349void __init apic_intr_mode_init(void)
1350{
1351 bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
1352
1353 switch (apic_intr_mode) {
1354 case APIC_PIC:
1355 pr_info("APIC: Keep in PIC mode(8259)\n");
1356 return;
1357 case APIC_VIRTUAL_WIRE:
1358 pr_info("APIC: Switch to virtual wire mode setup\n");
1359 break;
1360 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1361 pr_info("APIC: Switch to virtual wire mode setup with no configuration\n");
1362 upmode = true;
1363 break;
1364 case APIC_SYMMETRIC_IO:
1365 pr_info("APIC: Switch to symmetric I/O mode setup\n");
1366 break;
1367 case APIC_SYMMETRIC_IO_NO_ROUTING:
1368 pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n");
1369 break;
1370 }
1371
1372 x86_64_probe_apic();
1373
1374 x86_32_install_bigsmp();
1375
1376 if (x86_platform.apic_post_init)
1377 x86_platform.apic_post_init();
1378
1379 apic_bsp_setup(upmode);
1380}
1381
1382static void lapic_setup_esr(void)
1383{
1384 unsigned int oldvalue, value, maxlvt;
1385
1386 if (!lapic_is_integrated()) {
1387 pr_info("No ESR for 82489DX.\n");
1388 return;
1389 }
1390
1391 if (apic->disable_esr) {
1392 /*
1393 * Something untraceable is creating bad interrupts on
1394 * secondary quads ... for the moment, just leave the
1395 * ESR disabled - we can't do anything useful with the
1396 * errors anyway - mbligh
1397 */
1398 pr_info("Leaving ESR disabled.\n");
1399 return;
1400 }
1401
1402 maxlvt = lapic_get_maxlvt();
1403 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1404 apic_write(APIC_ESR, 0);
1405 oldvalue = apic_read(APIC_ESR);
1406
1407 /* enables sending errors */
1408 value = ERROR_APIC_VECTOR;
1409 apic_write(APIC_LVTERR, value);
1410
1411 /*
1412 * spec says clear errors after enabling vector.
1413 */
1414 if (maxlvt > 3)
1415 apic_write(APIC_ESR, 0);
1416 value = apic_read(APIC_ESR);
1417 if (value != oldvalue) {
1418 apic_pr_verbose("ESR value before enabling vector: 0x%08x after: 0x%08x\n",
1419 oldvalue, value);
1420 }
1421}
1422
1423#define APIC_IR_REGS APIC_ISR_NR
1424#define APIC_IR_BITS (APIC_IR_REGS * 32)
1425#define APIC_IR_MAPSIZE (APIC_IR_BITS / BITS_PER_LONG)
1426
1427union apic_ir {
1428 unsigned long map[APIC_IR_MAPSIZE];
1429 u32 regs[APIC_IR_REGS];
1430};
1431
1432static bool apic_check_and_ack(union apic_ir *irr, union apic_ir *isr)
1433{
1434 int i, bit;
1435
1436 /* Read the IRRs */
1437 for (i = 0; i < APIC_IR_REGS; i++)
1438 irr->regs[i] = apic_read(APIC_IRR + i * 0x10);
1439
1440 /* Read the ISRs */
1441 for (i = 0; i < APIC_IR_REGS; i++)
1442 isr->regs[i] = apic_read(APIC_ISR + i * 0x10);
1443
1444 /*
1445 * If the ISR map is not empty. ACK the APIC and run another round
1446 * to verify whether a pending IRR has been unblocked and turned
1447 * into a ISR.
1448 */
1449 if (!bitmap_empty(isr->map, APIC_IR_BITS)) {
1450 /*
1451 * There can be multiple ISR bits set when a high priority
1452 * interrupt preempted a lower priority one. Issue an ACK
1453 * per set bit.
1454 */
1455 for_each_set_bit(bit, isr->map, APIC_IR_BITS)
1456 apic_eoi();
1457 return true;
1458 }
1459
1460 return !bitmap_empty(irr->map, APIC_IR_BITS);
1461}
1462
1463/*
1464 * After a crash, we no longer service the interrupts and a pending
1465 * interrupt from previous kernel might still have ISR bit set.
1466 *
1467 * Most probably by now the CPU has serviced that pending interrupt and it
1468 * might not have done the apic_eoi() because it thought, interrupt
1469 * came from i8259 as ExtInt. LAPIC did not get EOI so it does not clear
1470 * the ISR bit and cpu thinks it has already serviced the interrupt. Hence
1471 * a vector might get locked. It was noticed for timer irq (vector
1472 * 0x31). Issue an extra EOI to clear ISR.
1473 *
1474 * If there are pending IRR bits they turn into ISR bits after a higher
1475 * priority ISR bit has been acked.
1476 */
1477static void apic_pending_intr_clear(void)
1478{
1479 union apic_ir irr, isr;
1480 unsigned int i;
1481
1482 /* 512 loops are way oversized and give the APIC a chance to obey. */
1483 for (i = 0; i < 512; i++) {
1484 if (!apic_check_and_ack(&irr, &isr))
1485 return;
1486 }
1487 /* Dump the IRR/ISR content if that failed */
1488 pr_warn("APIC: Stale IRR: %256pb ISR: %256pb\n", irr.map, isr.map);
1489}
1490
1491/**
1492 * setup_local_APIC - setup the local APIC
1493 *
1494 * Used to setup local APIC while initializing BSP or bringing up APs.
1495 * Always called with preemption disabled.
1496 */
1497static void setup_local_APIC(void)
1498{
1499 int cpu = smp_processor_id();
1500 unsigned int value;
1501
1502 if (apic_is_disabled) {
1503 disable_ioapic_support();
1504 return;
1505 }
1506
1507 /*
1508 * If this comes from kexec/kcrash the APIC might be enabled in
1509 * SPIV. Soft disable it before doing further initialization.
1510 */
1511 value = apic_read(APIC_SPIV);
1512 value &= ~APIC_SPIV_APIC_ENABLED;
1513 apic_write(APIC_SPIV, value);
1514
1515#ifdef CONFIG_X86_32
1516 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1517 if (lapic_is_integrated() && apic->disable_esr) {
1518 apic_write(APIC_ESR, 0);
1519 apic_write(APIC_ESR, 0);
1520 apic_write(APIC_ESR, 0);
1521 apic_write(APIC_ESR, 0);
1522 }
1523#endif
1524 /*
1525 * Intel recommends to set DFR, LDR and TPR before enabling
1526 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1527 * document number 292116).
1528 *
1529 * Except for APICs which operate in physical destination mode.
1530 */
1531 if (apic->init_apic_ldr)
1532 apic->init_apic_ldr();
1533
1534 /*
1535 * Set Task Priority to 'accept all except vectors 0-31'. An APIC
1536 * vector in the 16-31 range could be delivered if TPR == 0, but we
1537 * would think it's an exception and terrible things will happen. We
1538 * never change this later on.
1539 */
1540 value = apic_read(APIC_TASKPRI);
1541 value &= ~APIC_TPRI_MASK;
1542 value |= 0x10;
1543 apic_write(APIC_TASKPRI, value);
1544
1545 /* Clear eventually stale ISR/IRR bits */
1546 apic_pending_intr_clear();
1547
1548 /*
1549 * Now that we are all set up, enable the APIC
1550 */
1551 value = apic_read(APIC_SPIV);
1552 value &= ~APIC_VECTOR_MASK;
1553 /*
1554 * Enable APIC
1555 */
1556 value |= APIC_SPIV_APIC_ENABLED;
1557
1558#ifdef CONFIG_X86_32
1559 /*
1560 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1561 * certain networking cards. If high frequency interrupts are
1562 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1563 * entry is masked/unmasked at a high rate as well then sooner or
1564 * later IOAPIC line gets 'stuck', no more interrupts are received
1565 * from the device. If focus CPU is disabled then the hang goes
1566 * away, oh well :-(
1567 *
1568 * [ This bug can be reproduced easily with a level-triggered
1569 * PCI Ne2000 networking cards and PII/PIII processors, dual
1570 * BX chipset. ]
1571 */
1572 /*
1573 * Actually disabling the focus CPU check just makes the hang less
1574 * frequent as it makes the interrupt distribution model be more
1575 * like LRU than MRU (the short-term load is more even across CPUs).
1576 */
1577
1578 /*
1579 * - enable focus processor (bit==0)
1580 * - 64bit mode always use processor focus
1581 * so no need to set it
1582 */
1583 value &= ~APIC_SPIV_FOCUS_DISABLED;
1584#endif
1585
1586 /*
1587 * Set spurious IRQ vector
1588 */
1589 value |= SPURIOUS_APIC_VECTOR;
1590 apic_write(APIC_SPIV, value);
1591
1592 perf_events_lapic_init();
1593
1594 /*
1595 * Set up LVT0, LVT1:
1596 *
1597 * set up through-local-APIC on the boot CPU's LINT0. This is not
1598 * strictly necessary in pure symmetric-IO mode, but sometimes
1599 * we delegate interrupts to the 8259A.
1600 */
1601 /*
1602 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1603 */
1604 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1605 if (!cpu && (pic_mode || !value || ioapic_is_disabled)) {
1606 value = APIC_DM_EXTINT;
1607 apic_pr_verbose("Enabled ExtINT on CPU#%d\n", cpu);
1608 } else {
1609 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1610 apic_pr_verbose("Masked ExtINT on CPU#%d\n", cpu);
1611 }
1612 apic_write(APIC_LVT0, value);
1613
1614 /*
1615 * Only the BSP sees the LINT1 NMI signal by default. This can be
1616 * modified by apic_extnmi= boot option.
1617 */
1618 if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1619 apic_extnmi == APIC_EXTNMI_ALL)
1620 value = APIC_DM_NMI;
1621 else
1622 value = APIC_DM_NMI | APIC_LVT_MASKED;
1623
1624 /* Is 82489DX ? */
1625 if (!lapic_is_integrated())
1626 value |= APIC_LVT_LEVEL_TRIGGER;
1627 apic_write(APIC_LVT1, value);
1628
1629#ifdef CONFIG_X86_MCE_INTEL
1630 /* Recheck CMCI information after local APIC is up on CPU #0 */
1631 if (!cpu)
1632 cmci_recheck();
1633#endif
1634}
1635
1636static void end_local_APIC_setup(void)
1637{
1638 lapic_setup_esr();
1639
1640#ifdef CONFIG_X86_32
1641 {
1642 unsigned int value;
1643 /* Disable the local apic timer */
1644 value = apic_read(APIC_LVTT);
1645 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1646 apic_write(APIC_LVTT, value);
1647 }
1648#endif
1649
1650 apic_pm_activate();
1651}
1652
1653/*
1654 * APIC setup function for application processors. Called from smpboot.c
1655 */
1656void apic_ap_setup(void)
1657{
1658 setup_local_APIC();
1659 end_local_APIC_setup();
1660}
1661
1662static __init void apic_read_boot_cpu_id(bool x2apic)
1663{
1664 /*
1665 * This can be invoked from check_x2apic() before the APIC has been
1666 * selected. But that code knows for sure that the BIOS enabled
1667 * X2APIC.
1668 */
1669 if (x2apic) {
1670 boot_cpu_physical_apicid = native_apic_msr_read(APIC_ID);
1671 boot_cpu_apic_version = GET_APIC_VERSION(native_apic_msr_read(APIC_LVR));
1672 } else {
1673 boot_cpu_physical_apicid = read_apic_id();
1674 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
1675 }
1676 topology_register_boot_apic(boot_cpu_physical_apicid);
1677 x86_32_probe_bigsmp_early();
1678}
1679
1680#ifdef CONFIG_X86_X2APIC
1681int x2apic_mode;
1682EXPORT_SYMBOL_GPL(x2apic_mode);
1683
1684enum {
1685 X2APIC_OFF,
1686 X2APIC_DISABLED,
1687 /* All states below here have X2APIC enabled */
1688 X2APIC_ON,
1689 X2APIC_ON_LOCKED
1690};
1691static int x2apic_state;
1692
1693static bool x2apic_hw_locked(void)
1694{
1695 u64 x86_arch_cap_msr;
1696 u64 msr;
1697
1698 x86_arch_cap_msr = x86_read_arch_cap_msr();
1699 if (x86_arch_cap_msr & ARCH_CAP_XAPIC_DISABLE) {
1700 rdmsrl(MSR_IA32_XAPIC_DISABLE_STATUS, msr);
1701 return (msr & LEGACY_XAPIC_DISABLED);
1702 }
1703 return false;
1704}
1705
1706static void __x2apic_disable(void)
1707{
1708 u64 msr;
1709
1710 if (!boot_cpu_has(X86_FEATURE_APIC))
1711 return;
1712
1713 rdmsrl(MSR_IA32_APICBASE, msr);
1714 if (!(msr & X2APIC_ENABLE))
1715 return;
1716 /* Disable xapic and x2apic first and then reenable xapic mode */
1717 wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1718 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1719 printk_once(KERN_INFO "x2apic disabled\n");
1720}
1721
1722static void __x2apic_enable(void)
1723{
1724 u64 msr;
1725
1726 rdmsrl(MSR_IA32_APICBASE, msr);
1727 if (msr & X2APIC_ENABLE)
1728 return;
1729 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1730 printk_once(KERN_INFO "x2apic enabled\n");
1731}
1732
1733static int __init setup_nox2apic(char *str)
1734{
1735 if (x2apic_enabled()) {
1736 u32 apicid = native_apic_msr_read(APIC_ID);
1737
1738 if (apicid >= 255) {
1739 pr_warn("Apicid: %08x, cannot enforce nox2apic\n",
1740 apicid);
1741 return 0;
1742 }
1743 if (x2apic_hw_locked()) {
1744 pr_warn("APIC locked in x2apic mode, can't disable\n");
1745 return 0;
1746 }
1747 pr_warn("x2apic already enabled.\n");
1748 __x2apic_disable();
1749 }
1750 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1751 x2apic_state = X2APIC_DISABLED;
1752 x2apic_mode = 0;
1753 return 0;
1754}
1755early_param("nox2apic", setup_nox2apic);
1756
1757/* Called from cpu_init() to enable x2apic on (secondary) cpus */
1758void x2apic_setup(void)
1759{
1760 /*
1761 * Try to make the AP's APIC state match that of the BSP, but if the
1762 * BSP is unlocked and the AP is locked then there is a state mismatch.
1763 * Warn about the mismatch in case a GP fault occurs due to a locked AP
1764 * trying to be turned off.
1765 */
1766 if (x2apic_state != X2APIC_ON_LOCKED && x2apic_hw_locked())
1767 pr_warn("x2apic lock mismatch between BSP and AP.\n");
1768 /*
1769 * If x2apic is not in ON or LOCKED state, disable it if already enabled
1770 * from BIOS.
1771 */
1772 if (x2apic_state < X2APIC_ON) {
1773 __x2apic_disable();
1774 return;
1775 }
1776 __x2apic_enable();
1777}
1778
1779static __init void apic_set_fixmap(bool read_apic);
1780
1781static __init void x2apic_disable(void)
1782{
1783 u32 x2apic_id;
1784
1785 if (x2apic_state < X2APIC_ON)
1786 return;
1787
1788 x2apic_id = read_apic_id();
1789 if (x2apic_id >= 255)
1790 panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1791
1792 if (x2apic_hw_locked()) {
1793 pr_warn("Cannot disable locked x2apic, id: %08x\n", x2apic_id);
1794 return;
1795 }
1796
1797 __x2apic_disable();
1798
1799 x2apic_mode = 0;
1800 x2apic_state = X2APIC_DISABLED;
1801
1802 /*
1803 * Don't reread the APIC ID as it was already done from
1804 * check_x2apic() and the APIC driver still is a x2APIC variant,
1805 * which fails to do the read after x2APIC was disabled.
1806 */
1807 apic_set_fixmap(false);
1808}
1809
1810static __init void x2apic_enable(void)
1811{
1812 if (x2apic_state != X2APIC_OFF)
1813 return;
1814
1815 x2apic_mode = 1;
1816 x2apic_state = X2APIC_ON;
1817 __x2apic_enable();
1818}
1819
1820static __init void try_to_enable_x2apic(int remap_mode)
1821{
1822 if (x2apic_state == X2APIC_DISABLED)
1823 return;
1824
1825 if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1826 u32 apic_limit = 255;
1827
1828 /*
1829 * Using X2APIC without IR is not architecturally supported
1830 * on bare metal but may be supported in guests.
1831 */
1832 if (!x86_init.hyper.x2apic_available()) {
1833 pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1834 x2apic_disable();
1835 return;
1836 }
1837
1838 /*
1839 * If the hypervisor supports extended destination ID in
1840 * MSI, that increases the maximum APIC ID that can be
1841 * used for non-remapped IRQ domains.
1842 */
1843 if (x86_init.hyper.msi_ext_dest_id()) {
1844 virt_ext_dest_id = 1;
1845 apic_limit = 32767;
1846 }
1847
1848 /*
1849 * Without IR, all CPUs can be addressed by IOAPIC/MSI only
1850 * in physical mode, and CPUs with an APIC ID that cannot
1851 * be addressed must not be brought online.
1852 */
1853 x2apic_set_max_apicid(apic_limit);
1854 x2apic_phys = 1;
1855 }
1856 x2apic_enable();
1857}
1858
1859void __init check_x2apic(void)
1860{
1861 if (x2apic_enabled()) {
1862 pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1863 x2apic_mode = 1;
1864 if (x2apic_hw_locked())
1865 x2apic_state = X2APIC_ON_LOCKED;
1866 else
1867 x2apic_state = X2APIC_ON;
1868 apic_read_boot_cpu_id(true);
1869 } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) {
1870 x2apic_state = X2APIC_DISABLED;
1871 }
1872}
1873#else /* CONFIG_X86_X2APIC */
1874void __init check_x2apic(void)
1875{
1876 if (!apic_is_x2apic_enabled())
1877 return;
1878 /*
1879 * Checkme: Can we simply turn off x2APIC here instead of disabling the APIC?
1880 */
1881 pr_err("Kernel does not support x2APIC, please recompile with CONFIG_X86_X2APIC.\n");
1882 pr_err("Disabling APIC, expect reduced performance and functionality.\n");
1883
1884 apic_is_disabled = true;
1885 setup_clear_cpu_cap(X86_FEATURE_APIC);
1886}
1887
1888static inline void try_to_enable_x2apic(int remap_mode) { }
1889static inline void __x2apic_enable(void) { }
1890#endif /* !CONFIG_X86_X2APIC */
1891
1892void __init enable_IR_x2apic(void)
1893{
1894 unsigned long flags;
1895 int ret, ir_stat;
1896
1897 if (ioapic_is_disabled) {
1898 pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1899 return;
1900 }
1901
1902 ir_stat = irq_remapping_prepare();
1903 if (ir_stat < 0 && !x2apic_supported())
1904 return;
1905
1906 ret = save_ioapic_entries();
1907 if (ret) {
1908 pr_info("Saving IO-APIC state failed: %d\n", ret);
1909 return;
1910 }
1911
1912 local_irq_save(flags);
1913 legacy_pic->mask_all();
1914 mask_ioapic_entries();
1915
1916 /* If irq_remapping_prepare() succeeded, try to enable it */
1917 if (ir_stat >= 0)
1918 ir_stat = irq_remapping_enable();
1919 /* ir_stat contains the remap mode or an error code */
1920 try_to_enable_x2apic(ir_stat);
1921
1922 if (ir_stat < 0)
1923 restore_ioapic_entries();
1924 legacy_pic->restore_mask();
1925 local_irq_restore(flags);
1926}
1927
1928#ifdef CONFIG_X86_64
1929/*
1930 * Detect and enable local APICs on non-SMP boards.
1931 * Original code written by Keir Fraser.
1932 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1933 * not correctly set up (usually the APIC timer won't work etc.)
1934 */
1935static bool __init detect_init_APIC(void)
1936{
1937 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1938 pr_info("No local APIC present\n");
1939 return false;
1940 }
1941
1942 register_lapic_address(APIC_DEFAULT_PHYS_BASE);
1943 return true;
1944}
1945#else
1946
1947static bool __init apic_verify(unsigned long addr)
1948{
1949 u32 features, h, l;
1950
1951 /*
1952 * The APIC feature bit should now be enabled
1953 * in `cpuid'
1954 */
1955 features = cpuid_edx(1);
1956 if (!(features & (1 << X86_FEATURE_APIC))) {
1957 pr_warn("Could not enable APIC!\n");
1958 return false;
1959 }
1960 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1961
1962 /* The BIOS may have set up the APIC at some other address */
1963 if (boot_cpu_data.x86 >= 6) {
1964 rdmsr(MSR_IA32_APICBASE, l, h);
1965 if (l & MSR_IA32_APICBASE_ENABLE)
1966 addr = l & MSR_IA32_APICBASE_BASE;
1967 }
1968
1969 register_lapic_address(addr);
1970 pr_info("Found and enabled local APIC!\n");
1971 return true;
1972}
1973
1974bool __init apic_force_enable(unsigned long addr)
1975{
1976 u32 h, l;
1977
1978 if (apic_is_disabled)
1979 return false;
1980
1981 /*
1982 * Some BIOSes disable the local APIC in the APIC_BASE
1983 * MSR. This can only be done in software for Intel P6 or later
1984 * and AMD K7 (Model > 1) or later.
1985 */
1986 if (boot_cpu_data.x86 >= 6) {
1987 rdmsr(MSR_IA32_APICBASE, l, h);
1988 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1989 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1990 l &= ~MSR_IA32_APICBASE_BASE;
1991 l |= MSR_IA32_APICBASE_ENABLE | addr;
1992 wrmsr(MSR_IA32_APICBASE, l, h);
1993 enabled_via_apicbase = 1;
1994 }
1995 }
1996 return apic_verify(addr);
1997}
1998
1999/*
2000 * Detect and initialize APIC
2001 */
2002static bool __init detect_init_APIC(void)
2003{
2004 /* Disabled by kernel option? */
2005 if (apic_is_disabled)
2006 return false;
2007
2008 switch (boot_cpu_data.x86_vendor) {
2009 case X86_VENDOR_AMD:
2010 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
2011 (boot_cpu_data.x86 >= 15))
2012 break;
2013 goto no_apic;
2014 case X86_VENDOR_HYGON:
2015 break;
2016 case X86_VENDOR_INTEL:
2017 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
2018 (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC)))
2019 break;
2020 goto no_apic;
2021 default:
2022 goto no_apic;
2023 }
2024
2025 if (!boot_cpu_has(X86_FEATURE_APIC)) {
2026 /*
2027 * Over-ride BIOS and try to enable the local APIC only if
2028 * "lapic" specified.
2029 */
2030 if (!force_enable_local_apic) {
2031 pr_info("Local APIC disabled by BIOS -- "
2032 "you can enable it with \"lapic\"\n");
2033 return false;
2034 }
2035 if (!apic_force_enable(APIC_DEFAULT_PHYS_BASE))
2036 return false;
2037 } else {
2038 if (!apic_verify(APIC_DEFAULT_PHYS_BASE))
2039 return false;
2040 }
2041
2042 apic_pm_activate();
2043
2044 return true;
2045
2046no_apic:
2047 pr_info("No local APIC present or hardware disabled\n");
2048 return false;
2049}
2050#endif
2051
2052/**
2053 * init_apic_mappings - initialize APIC mappings
2054 */
2055void __init init_apic_mappings(void)
2056{
2057 if (apic_validate_deadline_timer())
2058 pr_info("TSC deadline timer available\n");
2059
2060 if (x2apic_mode)
2061 return;
2062
2063 if (!smp_found_config) {
2064 if (!detect_init_APIC()) {
2065 pr_info("APIC: disable apic facility\n");
2066 apic_disable();
2067 }
2068 }
2069}
2070
2071static __init void apic_set_fixmap(bool read_apic)
2072{
2073 set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);
2074 apic_mmio_base = APIC_BASE;
2075 apic_pr_verbose("Mapped APIC to %16lx (%16lx)\n", apic_mmio_base, mp_lapic_addr);
2076 if (read_apic)
2077 apic_read_boot_cpu_id(false);
2078}
2079
2080void __init register_lapic_address(unsigned long address)
2081{
2082 /* This should only happen once */
2083 WARN_ON_ONCE(mp_lapic_addr);
2084 mp_lapic_addr = address;
2085
2086 if (!x2apic_mode)
2087 apic_set_fixmap(true);
2088}
2089
2090/*
2091 * Local APIC interrupts
2092 */
2093
2094/*
2095 * Common handling code for spurious_interrupt and spurious_vector entry
2096 * points below. No point in allowing the compiler to inline it twice.
2097 */
2098static noinline void handle_spurious_interrupt(u8 vector)
2099{
2100 u32 v;
2101
2102 trace_spurious_apic_entry(vector);
2103
2104 inc_irq_stat(irq_spurious_count);
2105
2106 /*
2107 * If this is a spurious interrupt then do not acknowledge
2108 */
2109 if (vector == SPURIOUS_APIC_VECTOR) {
2110 /* See SDM vol 3 */
2111 pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n",
2112 smp_processor_id());
2113 goto out;
2114 }
2115
2116 /*
2117 * If it is a vectored one, verify it's set in the ISR. If set,
2118 * acknowledge it.
2119 */
2120 v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
2121 if (v & (1 << (vector & 0x1f))) {
2122 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
2123 vector, smp_processor_id());
2124 apic_eoi();
2125 } else {
2126 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
2127 vector, smp_processor_id());
2128 }
2129out:
2130 trace_spurious_apic_exit(vector);
2131}
2132
2133/**
2134 * spurious_interrupt - Catch all for interrupts raised on unused vectors
2135 * @regs: Pointer to pt_regs on stack
2136 * @vector: The vector number
2137 *
2138 * This is invoked from ASM entry code to catch all interrupts which
2139 * trigger on an entry which is routed to the common_spurious idtentry
2140 * point.
2141 */
2142DEFINE_IDTENTRY_IRQ(spurious_interrupt)
2143{
2144 handle_spurious_interrupt(vector);
2145}
2146
2147DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt)
2148{
2149 handle_spurious_interrupt(SPURIOUS_APIC_VECTOR);
2150}
2151
2152/*
2153 * This interrupt should never happen with our APIC/SMP architecture
2154 */
2155DEFINE_IDTENTRY_SYSVEC(sysvec_error_interrupt)
2156{
2157 static const char * const error_interrupt_reason[] = {
2158 "Send CS error", /* APIC Error Bit 0 */
2159 "Receive CS error", /* APIC Error Bit 1 */
2160 "Send accept error", /* APIC Error Bit 2 */
2161 "Receive accept error", /* APIC Error Bit 3 */
2162 "Redirectable IPI", /* APIC Error Bit 4 */
2163 "Send illegal vector", /* APIC Error Bit 5 */
2164 "Received illegal vector", /* APIC Error Bit 6 */
2165 "Illegal register address", /* APIC Error Bit 7 */
2166 };
2167 u32 v, i = 0;
2168
2169 trace_error_apic_entry(ERROR_APIC_VECTOR);
2170
2171 /* First tickle the hardware, only then report what went on. -- REW */
2172 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */
2173 apic_write(APIC_ESR, 0);
2174 v = apic_read(APIC_ESR);
2175 apic_eoi();
2176 atomic_inc(&irq_err_count);
2177
2178 apic_pr_debug("APIC error on CPU%d: %02x", smp_processor_id(), v);
2179
2180 v &= 0xff;
2181 while (v) {
2182 if (v & 0x1)
2183 apic_pr_debug_cont(" : %s", error_interrupt_reason[i]);
2184 i++;
2185 v >>= 1;
2186 }
2187
2188 apic_pr_debug_cont("\n");
2189
2190 trace_error_apic_exit(ERROR_APIC_VECTOR);
2191}
2192
2193/**
2194 * connect_bsp_APIC - attach the APIC to the interrupt system
2195 */
2196static void __init connect_bsp_APIC(void)
2197{
2198#ifdef CONFIG_X86_32
2199 if (pic_mode) {
2200 /*
2201 * Do not trust the local APIC being empty at bootup.
2202 */
2203 clear_local_APIC();
2204 /*
2205 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
2206 * local APIC to INT and NMI lines.
2207 */
2208 apic_pr_verbose("Leaving PIC mode, enabling APIC mode.\n");
2209 imcr_pic_to_apic();
2210 }
2211#endif
2212}
2213
2214/**
2215 * disconnect_bsp_APIC - detach the APIC from the interrupt system
2216 * @virt_wire_setup: indicates, whether virtual wire mode is selected
2217 *
2218 * Virtual wire mode is necessary to deliver legacy interrupts even when the
2219 * APIC is disabled.
2220 */
2221void disconnect_bsp_APIC(int virt_wire_setup)
2222{
2223 unsigned int value;
2224
2225#ifdef CONFIG_X86_32
2226 if (pic_mode) {
2227 /*
2228 * Put the board back into PIC mode (has an effect only on
2229 * certain older boards). Note that APIC interrupts, including
2230 * IPIs, won't work beyond this point! The only exception are
2231 * INIT IPIs.
2232 */
2233 apic_pr_verbose("Disabling APIC mode, entering PIC mode.\n");
2234 imcr_apic_to_pic();
2235 return;
2236 }
2237#endif
2238
2239 /* Go back to Virtual Wire compatibility mode */
2240
2241 /* For the spurious interrupt use vector F, and enable it */
2242 value = apic_read(APIC_SPIV);
2243 value &= ~APIC_VECTOR_MASK;
2244 value |= APIC_SPIV_APIC_ENABLED;
2245 value |= 0xf;
2246 apic_write(APIC_SPIV, value);
2247
2248 if (!virt_wire_setup) {
2249 /*
2250 * For LVT0 make it edge triggered, active high,
2251 * external and enabled
2252 */
2253 value = apic_read(APIC_LVT0);
2254 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2255 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2256 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2257 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2258 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2259 apic_write(APIC_LVT0, value);
2260 } else {
2261 /* Disable LVT0 */
2262 apic_write(APIC_LVT0, APIC_LVT_MASKED);
2263 }
2264
2265 /*
2266 * For LVT1 make it edge triggered, active high,
2267 * nmi and enabled
2268 */
2269 value = apic_read(APIC_LVT1);
2270 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2271 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2272 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2273 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2274 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2275 apic_write(APIC_LVT1, value);
2276}
2277
2278void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
2279 bool dmar)
2280{
2281 memset(msg, 0, sizeof(*msg));
2282
2283 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
2284 msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical;
2285 msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF;
2286
2287 msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED;
2288 msg->arch_data.vector = cfg->vector;
2289
2290 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
2291 /*
2292 * Only the IOMMU itself can use the trick of putting destination
2293 * APIC ID into the high bits of the address. Anything else would
2294 * just be writing to memory if it tried that, and needs IR to
2295 * address APICs which can't be addressed in the normal 32-bit
2296 * address range at 0xFFExxxxx. That is typically just 8 bits, but
2297 * some hypervisors allow the extended destination ID field in bits
2298 * 5-11 to be used, giving support for 15 bits of APIC IDs in total.
2299 */
2300 if (dmar)
2301 msg->arch_addr_hi.destid_8_31 = cfg->dest_apicid >> 8;
2302 else if (virt_ext_dest_id && cfg->dest_apicid < 0x8000)
2303 msg->arch_addr_lo.virt_destid_8_14 = cfg->dest_apicid >> 8;
2304 else
2305 WARN_ON_ONCE(cfg->dest_apicid > 0xFF);
2306}
2307
2308u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid)
2309{
2310 u32 dest = msg->arch_addr_lo.destid_0_7;
2311
2312 if (extid)
2313 dest |= msg->arch_addr_hi.destid_8_31 << 8;
2314 return dest;
2315}
2316EXPORT_SYMBOL_GPL(x86_msi_msg_get_destid);
2317
2318static void __init apic_bsp_up_setup(void)
2319{
2320 reset_phys_cpu_present_map(boot_cpu_physical_apicid);
2321}
2322
2323/**
2324 * apic_bsp_setup - Setup function for local apic and io-apic
2325 * @upmode: Force UP mode (for APIC_init_uniprocessor)
2326 */
2327static void __init apic_bsp_setup(bool upmode)
2328{
2329 connect_bsp_APIC();
2330 if (upmode)
2331 apic_bsp_up_setup();
2332 setup_local_APIC();
2333
2334 enable_IO_APIC();
2335 end_local_APIC_setup();
2336 irq_remap_enable_fault_handling();
2337 setup_IO_APIC();
2338 lapic_update_legacy_vectors();
2339}
2340
2341#ifdef CONFIG_UP_LATE_INIT
2342void __init up_late_init(void)
2343{
2344 if (apic_intr_mode == APIC_PIC)
2345 return;
2346
2347 /* Setup local timer */
2348 x86_init.timers.setup_percpu_clockev();
2349}
2350#endif
2351
2352/*
2353 * Power management
2354 */
2355#ifdef CONFIG_PM
2356
2357static struct {
2358 /*
2359 * 'active' is true if the local APIC was enabled by us and
2360 * not the BIOS; this signifies that we are also responsible
2361 * for disabling it before entering apm/acpi suspend
2362 */
2363 int active;
2364 /* r/w apic fields */
2365 u32 apic_id;
2366 unsigned int apic_taskpri;
2367 unsigned int apic_ldr;
2368 unsigned int apic_dfr;
2369 unsigned int apic_spiv;
2370 unsigned int apic_lvtt;
2371 unsigned int apic_lvtpc;
2372 unsigned int apic_lvt0;
2373 unsigned int apic_lvt1;
2374 unsigned int apic_lvterr;
2375 unsigned int apic_tmict;
2376 unsigned int apic_tdcr;
2377 unsigned int apic_thmr;
2378 unsigned int apic_cmci;
2379} apic_pm_state;
2380
2381static int lapic_suspend(void)
2382{
2383 unsigned long flags;
2384 int maxlvt;
2385
2386 if (!apic_pm_state.active)
2387 return 0;
2388
2389 maxlvt = lapic_get_maxlvt();
2390
2391 apic_pm_state.apic_id = apic_read(APIC_ID);
2392 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2393 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2394 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2395 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2396 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2397 if (maxlvt >= 4)
2398 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2399 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2400 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2401 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2402 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2403 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2404#ifdef CONFIG_X86_THERMAL_VECTOR
2405 if (maxlvt >= 5)
2406 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2407#endif
2408#ifdef CONFIG_X86_MCE_INTEL
2409 if (maxlvt >= 6)
2410 apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2411#endif
2412
2413 local_irq_save(flags);
2414
2415 /*
2416 * Mask IOAPIC before disabling the local APIC to prevent stale IRR
2417 * entries on some implementations.
2418 */
2419 mask_ioapic_entries();
2420
2421 disable_local_APIC();
2422
2423 irq_remapping_disable();
2424
2425 local_irq_restore(flags);
2426 return 0;
2427}
2428
2429static void lapic_resume(void)
2430{
2431 unsigned int l, h;
2432 unsigned long flags;
2433 int maxlvt;
2434
2435 if (!apic_pm_state.active)
2436 return;
2437
2438 local_irq_save(flags);
2439
2440 /*
2441 * IO-APIC and PIC have their own resume routines.
2442 * We just mask them here to make sure the interrupt
2443 * subsystem is completely quiet while we enable x2apic
2444 * and interrupt-remapping.
2445 */
2446 mask_ioapic_entries();
2447 legacy_pic->mask_all();
2448
2449 if (x2apic_mode) {
2450 __x2apic_enable();
2451 } else {
2452 /*
2453 * Make sure the APICBASE points to the right address
2454 *
2455 * FIXME! This will be wrong if we ever support suspend on
2456 * SMP! We'll need to do this as part of the CPU restore!
2457 */
2458 if (boot_cpu_data.x86 >= 6) {
2459 rdmsr(MSR_IA32_APICBASE, l, h);
2460 l &= ~MSR_IA32_APICBASE_BASE;
2461 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2462 wrmsr(MSR_IA32_APICBASE, l, h);
2463 }
2464 }
2465
2466 maxlvt = lapic_get_maxlvt();
2467 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2468 apic_write(APIC_ID, apic_pm_state.apic_id);
2469 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2470 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2471 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2472 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2473 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2474 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2475#ifdef CONFIG_X86_THERMAL_VECTOR
2476 if (maxlvt >= 5)
2477 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2478#endif
2479#ifdef CONFIG_X86_MCE_INTEL
2480 if (maxlvt >= 6)
2481 apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2482#endif
2483 if (maxlvt >= 4)
2484 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2485 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2486 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2487 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2488 apic_write(APIC_ESR, 0);
2489 apic_read(APIC_ESR);
2490 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2491 apic_write(APIC_ESR, 0);
2492 apic_read(APIC_ESR);
2493
2494 irq_remapping_reenable(x2apic_mode);
2495
2496 local_irq_restore(flags);
2497}
2498
2499/*
2500 * This device has no shutdown method - fully functioning local APICs
2501 * are needed on every CPU up until machine_halt/restart/poweroff.
2502 */
2503
2504static struct syscore_ops lapic_syscore_ops = {
2505 .resume = lapic_resume,
2506 .suspend = lapic_suspend,
2507};
2508
2509static void apic_pm_activate(void)
2510{
2511 apic_pm_state.active = 1;
2512}
2513
2514static int __init init_lapic_sysfs(void)
2515{
2516 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2517 if (boot_cpu_has(X86_FEATURE_APIC))
2518 register_syscore_ops(&lapic_syscore_ops);
2519
2520 return 0;
2521}
2522
2523/* local apic needs to resume before other devices access its registers. */
2524core_initcall(init_lapic_sysfs);
2525
2526#else /* CONFIG_PM */
2527
2528static void apic_pm_activate(void) { }
2529
2530#endif /* CONFIG_PM */
2531
2532#ifdef CONFIG_X86_64
2533
2534static int multi_checked;
2535static int multi;
2536
2537static int set_multi(const struct dmi_system_id *d)
2538{
2539 if (multi)
2540 return 0;
2541 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2542 multi = 1;
2543 return 0;
2544}
2545
2546static const struct dmi_system_id multi_dmi_table[] = {
2547 {
2548 .callback = set_multi,
2549 .ident = "IBM System Summit2",
2550 .matches = {
2551 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2552 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2553 },
2554 },
2555 {}
2556};
2557
2558static void dmi_check_multi(void)
2559{
2560 if (multi_checked)
2561 return;
2562
2563 dmi_check_system(multi_dmi_table);
2564 multi_checked = 1;
2565}
2566
2567/*
2568 * apic_is_clustered_box() -- Check if we can expect good TSC
2569 *
2570 * Thus far, the major user of this is IBM's Summit2 series:
2571 * Clustered boxes may have unsynced TSC problems if they are
2572 * multi-chassis.
2573 * Use DMI to check them
2574 */
2575int apic_is_clustered_box(void)
2576{
2577 dmi_check_multi();
2578 return multi;
2579}
2580#endif
2581
2582/*
2583 * APIC command line parameters
2584 */
2585static int __init setup_disableapic(char *arg)
2586{
2587 apic_is_disabled = true;
2588 setup_clear_cpu_cap(X86_FEATURE_APIC);
2589 return 0;
2590}
2591early_param("disableapic", setup_disableapic);
2592
2593/* same as disableapic, for compatibility */
2594static int __init setup_nolapic(char *arg)
2595{
2596 return setup_disableapic(arg);
2597}
2598early_param("nolapic", setup_nolapic);
2599
2600static int __init parse_lapic_timer_c2_ok(char *arg)
2601{
2602 local_apic_timer_c2_ok = 1;
2603 return 0;
2604}
2605early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2606
2607static int __init parse_disable_apic_timer(char *arg)
2608{
2609 disable_apic_timer = 1;
2610 return 0;
2611}
2612early_param("noapictimer", parse_disable_apic_timer);
2613
2614static int __init parse_nolapic_timer(char *arg)
2615{
2616 disable_apic_timer = 1;
2617 return 0;
2618}
2619early_param("nolapic_timer", parse_nolapic_timer);
2620
2621static int __init apic_set_verbosity(char *arg)
2622{
2623 if (!arg) {
2624 if (IS_ENABLED(CONFIG_X86_32))
2625 return -EINVAL;
2626
2627 ioapic_is_disabled = false;
2628 return 0;
2629 }
2630
2631 if (strcmp("debug", arg) == 0)
2632 apic_verbosity = APIC_DEBUG;
2633 else if (strcmp("verbose", arg) == 0)
2634 apic_verbosity = APIC_VERBOSE;
2635#ifdef CONFIG_X86_64
2636 else {
2637 pr_warn("APIC Verbosity level %s not recognised"
2638 " use apic=verbose or apic=debug\n", arg);
2639 return -EINVAL;
2640 }
2641#endif
2642
2643 return 0;
2644}
2645early_param("apic", apic_set_verbosity);
2646
2647static int __init lapic_insert_resource(void)
2648{
2649 if (!apic_mmio_base)
2650 return -1;
2651
2652 /* Put local APIC into the resource map. */
2653 lapic_resource.start = apic_mmio_base;
2654 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2655 insert_resource(&iomem_resource, &lapic_resource);
2656
2657 return 0;
2658}
2659
2660/*
2661 * need call insert after e820__reserve_resources()
2662 * that is using request_resource
2663 */
2664late_initcall(lapic_insert_resource);
2665
2666static int __init apic_set_extnmi(char *arg)
2667{
2668 if (!arg)
2669 return -EINVAL;
2670
2671 if (!strncmp("all", arg, 3))
2672 apic_extnmi = APIC_EXTNMI_ALL;
2673 else if (!strncmp("none", arg, 4))
2674 apic_extnmi = APIC_EXTNMI_NONE;
2675 else if (!strncmp("bsp", arg, 3))
2676 apic_extnmi = APIC_EXTNMI_BSP;
2677 else {
2678 pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2679 return -EINVAL;
2680 }
2681
2682 return 0;
2683}
2684early_param("apic_extnmi", apic_set_extnmi);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Local APIC handling, local APIC timers
4 *
5 * (c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
6 *
7 * Fixes
8 * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
9 * thanks to Eric Gilmore
10 * and Rolf G. Tews
11 * for testing these extensively.
12 * Maciej W. Rozycki : Various updates and fixes.
13 * Mikael Pettersson : Power Management for UP-APIC.
14 * Pavel Machek and
15 * Mikael Pettersson : PM converted to driver model.
16 */
17
18#include <linux/perf_event.h>
19#include <linux/kernel_stat.h>
20#include <linux/mc146818rtc.h>
21#include <linux/acpi_pmtmr.h>
22#include <linux/clockchips.h>
23#include <linux/interrupt.h>
24#include <linux/memblock.h>
25#include <linux/ftrace.h>
26#include <linux/ioport.h>
27#include <linux/export.h>
28#include <linux/syscore_ops.h>
29#include <linux/delay.h>
30#include <linux/timex.h>
31#include <linux/i8253.h>
32#include <linux/dmar.h>
33#include <linux/init.h>
34#include <linux/cpu.h>
35#include <linux/dmi.h>
36#include <linux/smp.h>
37#include <linux/mm.h>
38
39#include <asm/trace/irq_vectors.h>
40#include <asm/irq_remapping.h>
41#include <asm/perf_event.h>
42#include <asm/x86_init.h>
43#include <linux/atomic.h>
44#include <asm/barrier.h>
45#include <asm/mpspec.h>
46#include <asm/i8259.h>
47#include <asm/proto.h>
48#include <asm/traps.h>
49#include <asm/apic.h>
50#include <asm/acpi.h>
51#include <asm/io_apic.h>
52#include <asm/desc.h>
53#include <asm/hpet.h>
54#include <asm/mtrr.h>
55#include <asm/time.h>
56#include <asm/smp.h>
57#include <asm/mce.h>
58#include <asm/tsc.h>
59#include <asm/hypervisor.h>
60#include <asm/cpu_device_id.h>
61#include <asm/intel-family.h>
62#include <asm/irq_regs.h>
63
64unsigned int num_processors;
65
66unsigned disabled_cpus;
67
68/* Processor that is doing the boot up */
69unsigned int boot_cpu_physical_apicid __ro_after_init = -1U;
70EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
71
72u8 boot_cpu_apic_version __ro_after_init;
73
74/*
75 * The highest APIC ID seen during enumeration.
76 */
77static unsigned int max_physical_apicid;
78
79/*
80 * Bitmask of physically existing CPUs:
81 */
82physid_mask_t phys_cpu_present_map;
83
84/*
85 * Processor to be disabled specified by kernel parameter
86 * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
87 * avoid undefined behaviour caused by sending INIT from AP to BSP.
88 */
89static unsigned int disabled_cpu_apicid __ro_after_init = BAD_APICID;
90
91/*
92 * This variable controls which CPUs receive external NMIs. By default,
93 * external NMIs are delivered only to the BSP.
94 */
95static int apic_extnmi __ro_after_init = APIC_EXTNMI_BSP;
96
97/*
98 * Hypervisor supports 15 bits of APIC ID in MSI Extended Destination ID
99 */
100static bool virt_ext_dest_id __ro_after_init;
101
102/*
103 * Map cpu index to physical APIC ID
104 */
105DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
106DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID);
107DEFINE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid, U32_MAX);
108EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
109EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
110EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_acpiid);
111
112#ifdef CONFIG_X86_32
113
114/*
115 * On x86_32, the mapping between cpu and logical apicid may vary
116 * depending on apic in use. The following early percpu variable is
117 * used for the mapping. This is where the behaviors of x86_64 and 32
118 * actually diverge. Let's keep it ugly for now.
119 */
120DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID);
121
122/* Local APIC was disabled by the BIOS and enabled by the kernel */
123static int enabled_via_apicbase __ro_after_init;
124
125/*
126 * Handle interrupt mode configuration register (IMCR).
127 * This register controls whether the interrupt signals
128 * that reach the BSP come from the master PIC or from the
129 * local APIC. Before entering Symmetric I/O Mode, either
130 * the BIOS or the operating system must switch out of
131 * PIC Mode by changing the IMCR.
132 */
133static inline void imcr_pic_to_apic(void)
134{
135 /* select IMCR register */
136 outb(0x70, 0x22);
137 /* NMI and 8259 INTR go through APIC */
138 outb(0x01, 0x23);
139}
140
141static inline void imcr_apic_to_pic(void)
142{
143 /* select IMCR register */
144 outb(0x70, 0x22);
145 /* NMI and 8259 INTR go directly to BSP */
146 outb(0x00, 0x23);
147}
148#endif
149
150/*
151 * Knob to control our willingness to enable the local APIC.
152 *
153 * +1=force-enable
154 */
155static int force_enable_local_apic __initdata;
156
157/*
158 * APIC command line parameters
159 */
160static int __init parse_lapic(char *arg)
161{
162 if (IS_ENABLED(CONFIG_X86_32) && !arg)
163 force_enable_local_apic = 1;
164 else if (arg && !strncmp(arg, "notscdeadline", 13))
165 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
166 return 0;
167}
168early_param("lapic", parse_lapic);
169
170#ifdef CONFIG_X86_64
171static int apic_calibrate_pmtmr __initdata;
172static __init int setup_apicpmtimer(char *s)
173{
174 apic_calibrate_pmtmr = 1;
175 notsc_setup(NULL);
176 return 0;
177}
178__setup("apicpmtimer", setup_apicpmtimer);
179#endif
180
181unsigned long mp_lapic_addr __ro_after_init;
182int disable_apic __ro_after_init;
183/* Disable local APIC timer from the kernel commandline or via dmi quirk */
184static int disable_apic_timer __initdata;
185/* Local APIC timer works in C2 */
186int local_apic_timer_c2_ok __ro_after_init;
187EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
188
189/*
190 * Debug level, exported for io_apic.c
191 */
192int apic_verbosity __ro_after_init;
193
194int pic_mode __ro_after_init;
195
196/* Have we found an MP table */
197int smp_found_config __ro_after_init;
198
199static struct resource lapic_resource = {
200 .name = "Local APIC",
201 .flags = IORESOURCE_MEM | IORESOURCE_BUSY,
202};
203
204unsigned int lapic_timer_period = 0;
205
206static void apic_pm_activate(void);
207
208static unsigned long apic_phys __ro_after_init;
209
210/*
211 * Get the LAPIC version
212 */
213static inline int lapic_get_version(void)
214{
215 return GET_APIC_VERSION(apic_read(APIC_LVR));
216}
217
218/*
219 * Check, if the APIC is integrated or a separate chip
220 */
221static inline int lapic_is_integrated(void)
222{
223 return APIC_INTEGRATED(lapic_get_version());
224}
225
226/*
227 * Check, whether this is a modern or a first generation APIC
228 */
229static int modern_apic(void)
230{
231 /* AMD systems use old APIC versions, so check the CPU */
232 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
233 boot_cpu_data.x86 >= 0xf)
234 return 1;
235
236 /* Hygon systems use modern APIC */
237 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
238 return 1;
239
240 return lapic_get_version() >= 0x14;
241}
242
243/*
244 * right after this call apic become NOOP driven
245 * so apic->write/read doesn't do anything
246 */
247static void __init apic_disable(void)
248{
249 pr_info("APIC: switched to apic NOOP\n");
250 apic = &apic_noop;
251}
252
253void native_apic_wait_icr_idle(void)
254{
255 while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
256 cpu_relax();
257}
258
259u32 native_safe_apic_wait_icr_idle(void)
260{
261 u32 send_status;
262 int timeout;
263
264 timeout = 0;
265 do {
266 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
267 if (!send_status)
268 break;
269 inc_irq_stat(icr_read_retry_count);
270 udelay(100);
271 } while (timeout++ < 1000);
272
273 return send_status;
274}
275
276void native_apic_icr_write(u32 low, u32 id)
277{
278 unsigned long flags;
279
280 local_irq_save(flags);
281 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
282 apic_write(APIC_ICR, low);
283 local_irq_restore(flags);
284}
285
286u64 native_apic_icr_read(void)
287{
288 u32 icr1, icr2;
289
290 icr2 = apic_read(APIC_ICR2);
291 icr1 = apic_read(APIC_ICR);
292
293 return icr1 | ((u64)icr2 << 32);
294}
295
296#ifdef CONFIG_X86_32
297/**
298 * get_physical_broadcast - Get number of physical broadcast IDs
299 */
300int get_physical_broadcast(void)
301{
302 return modern_apic() ? 0xff : 0xf;
303}
304#endif
305
306/**
307 * lapic_get_maxlvt - get the maximum number of local vector table entries
308 */
309int lapic_get_maxlvt(void)
310{
311 /*
312 * - we always have APIC integrated on 64bit mode
313 * - 82489DXs do not report # of LVT entries
314 */
315 return lapic_is_integrated() ? GET_APIC_MAXLVT(apic_read(APIC_LVR)) : 2;
316}
317
318/*
319 * Local APIC timer
320 */
321
322/* Clock divisor */
323#define APIC_DIVISOR 16
324#define TSC_DIVISOR 8
325
326/*
327 * This function sets up the local APIC timer, with a timeout of
328 * 'clocks' APIC bus clock. During calibration we actually call
329 * this function twice on the boot CPU, once with a bogus timeout
330 * value, second time for real. The other (noncalibrating) CPUs
331 * call this function only once, with the real, calibrated value.
332 *
333 * We do reads before writes even if unnecessary, to get around the
334 * P5 APIC double write bug.
335 */
336static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
337{
338 unsigned int lvtt_value, tmp_value;
339
340 lvtt_value = LOCAL_TIMER_VECTOR;
341 if (!oneshot)
342 lvtt_value |= APIC_LVT_TIMER_PERIODIC;
343 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
344 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
345
346 if (!lapic_is_integrated())
347 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
348
349 if (!irqen)
350 lvtt_value |= APIC_LVT_MASKED;
351
352 apic_write(APIC_LVTT, lvtt_value);
353
354 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
355 /*
356 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
357 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
358 * According to Intel, MFENCE can do the serialization here.
359 */
360 asm volatile("mfence" : : : "memory");
361 return;
362 }
363
364 /*
365 * Divide PICLK by 16
366 */
367 tmp_value = apic_read(APIC_TDCR);
368 apic_write(APIC_TDCR,
369 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
370 APIC_TDR_DIV_16);
371
372 if (!oneshot)
373 apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
374}
375
376/*
377 * Setup extended LVT, AMD specific
378 *
379 * Software should use the LVT offsets the BIOS provides. The offsets
380 * are determined by the subsystems using it like those for MCE
381 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
382 * are supported. Beginning with family 10h at least 4 offsets are
383 * available.
384 *
385 * Since the offsets must be consistent for all cores, we keep track
386 * of the LVT offsets in software and reserve the offset for the same
387 * vector also to be used on other cores. An offset is freed by
388 * setting the entry to APIC_EILVT_MASKED.
389 *
390 * If the BIOS is right, there should be no conflicts. Otherwise a
391 * "[Firmware Bug]: ..." error message is generated. However, if
392 * software does not properly determines the offsets, it is not
393 * necessarily a BIOS bug.
394 */
395
396static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
397
398static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
399{
400 return (old & APIC_EILVT_MASKED)
401 || (new == APIC_EILVT_MASKED)
402 || ((new & ~APIC_EILVT_MASKED) == old);
403}
404
405static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
406{
407 unsigned int rsvd, vector;
408
409 if (offset >= APIC_EILVT_NR_MAX)
410 return ~0;
411
412 rsvd = atomic_read(&eilvt_offsets[offset]);
413 do {
414 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
415 if (vector && !eilvt_entry_is_changeable(vector, new))
416 /* may not change if vectors are different */
417 return rsvd;
418 rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
419 } while (rsvd != new);
420
421 rsvd &= ~APIC_EILVT_MASKED;
422 if (rsvd && rsvd != vector)
423 pr_info("LVT offset %d assigned for vector 0x%02x\n",
424 offset, rsvd);
425
426 return new;
427}
428
429/*
430 * If mask=1, the LVT entry does not generate interrupts while mask=0
431 * enables the vector. See also the BKDGs. Must be called with
432 * preemption disabled.
433 */
434
435int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
436{
437 unsigned long reg = APIC_EILVTn(offset);
438 unsigned int new, old, reserved;
439
440 new = (mask << 16) | (msg_type << 8) | vector;
441 old = apic_read(reg);
442 reserved = reserve_eilvt_offset(offset, new);
443
444 if (reserved != new) {
445 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
446 "vector 0x%x, but the register is already in use for "
447 "vector 0x%x on another cpu\n",
448 smp_processor_id(), reg, offset, new, reserved);
449 return -EINVAL;
450 }
451
452 if (!eilvt_entry_is_changeable(old, new)) {
453 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
454 "vector 0x%x, but the register is already in use for "
455 "vector 0x%x on this cpu\n",
456 smp_processor_id(), reg, offset, new, old);
457 return -EBUSY;
458 }
459
460 apic_write(reg, new);
461
462 return 0;
463}
464EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
465
466/*
467 * Program the next event, relative to now
468 */
469static int lapic_next_event(unsigned long delta,
470 struct clock_event_device *evt)
471{
472 apic_write(APIC_TMICT, delta);
473 return 0;
474}
475
476static int lapic_next_deadline(unsigned long delta,
477 struct clock_event_device *evt)
478{
479 u64 tsc;
480
481 /* This MSR is special and need a special fence: */
482 weak_wrmsr_fence();
483
484 tsc = rdtsc();
485 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
486 return 0;
487}
488
489static int lapic_timer_shutdown(struct clock_event_device *evt)
490{
491 unsigned int v;
492
493 /* Lapic used as dummy for broadcast ? */
494 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
495 return 0;
496
497 v = apic_read(APIC_LVTT);
498 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
499 apic_write(APIC_LVTT, v);
500 apic_write(APIC_TMICT, 0);
501 return 0;
502}
503
504static inline int
505lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
506{
507 /* Lapic used as dummy for broadcast ? */
508 if (evt->features & CLOCK_EVT_FEAT_DUMMY)
509 return 0;
510
511 __setup_APIC_LVTT(lapic_timer_period, oneshot, 1);
512 return 0;
513}
514
515static int lapic_timer_set_periodic(struct clock_event_device *evt)
516{
517 return lapic_timer_set_periodic_oneshot(evt, false);
518}
519
520static int lapic_timer_set_oneshot(struct clock_event_device *evt)
521{
522 return lapic_timer_set_periodic_oneshot(evt, true);
523}
524
525/*
526 * Local APIC timer broadcast function
527 */
528static void lapic_timer_broadcast(const struct cpumask *mask)
529{
530#ifdef CONFIG_SMP
531 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
532#endif
533}
534
535
536/*
537 * The local apic timer can be used for any function which is CPU local.
538 */
539static struct clock_event_device lapic_clockevent = {
540 .name = "lapic",
541 .features = CLOCK_EVT_FEAT_PERIODIC |
542 CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
543 | CLOCK_EVT_FEAT_DUMMY,
544 .shift = 32,
545 .set_state_shutdown = lapic_timer_shutdown,
546 .set_state_periodic = lapic_timer_set_periodic,
547 .set_state_oneshot = lapic_timer_set_oneshot,
548 .set_state_oneshot_stopped = lapic_timer_shutdown,
549 .set_next_event = lapic_next_event,
550 .broadcast = lapic_timer_broadcast,
551 .rating = 100,
552 .irq = -1,
553};
554static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
555
556static const struct x86_cpu_id deadline_match[] __initconst = {
557 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x2, 0x2), 0x3a), /* EP */
558 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(HASWELL_X, X86_STEPPINGS(0x4, 0x4), 0x0f), /* EX */
559
560 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_X, 0x0b000020),
561
562 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x2, 0x2), 0x00000011),
563 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x3, 0x3), 0x0700000e),
564 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x4, 0x4), 0x0f00000c),
565 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(BROADWELL_D, X86_STEPPINGS(0x5, 0x5), 0x0e000003),
566
567 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x3, 0x3), 0x01000136),
568 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x4, 0x4), 0x02000014),
569 X86_MATCH_INTEL_FAM6_MODEL_STEPPINGS(SKYLAKE_X, X86_STEPPINGS(0x5, 0xf), 0),
570
571 X86_MATCH_INTEL_FAM6_MODEL( HASWELL, 0x22),
572 X86_MATCH_INTEL_FAM6_MODEL( HASWELL_L, 0x20),
573 X86_MATCH_INTEL_FAM6_MODEL( HASWELL_G, 0x17),
574
575 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL, 0x25),
576 X86_MATCH_INTEL_FAM6_MODEL( BROADWELL_G, 0x17),
577
578 X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE_L, 0xb2),
579 X86_MATCH_INTEL_FAM6_MODEL( SKYLAKE, 0xb2),
580
581 X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE_L, 0x52),
582 X86_MATCH_INTEL_FAM6_MODEL( KABYLAKE, 0x52),
583
584 {},
585};
586
587static __init bool apic_validate_deadline_timer(void)
588{
589 const struct x86_cpu_id *m;
590 u32 rev;
591
592 if (!boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
593 return false;
594 if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
595 return true;
596
597 m = x86_match_cpu(deadline_match);
598 if (!m)
599 return true;
600
601 rev = (u32)m->driver_data;
602
603 if (boot_cpu_data.microcode >= rev)
604 return true;
605
606 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
607 pr_err(FW_BUG "TSC_DEADLINE disabled due to Errata; "
608 "please update microcode to version: 0x%x (or later)\n", rev);
609 return false;
610}
611
612/*
613 * Setup the local APIC timer for this CPU. Copy the initialized values
614 * of the boot CPU and register the clock event in the framework.
615 */
616static void setup_APIC_timer(void)
617{
618 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
619
620 if (this_cpu_has(X86_FEATURE_ARAT)) {
621 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
622 /* Make LAPIC timer preferable over percpu HPET */
623 lapic_clockevent.rating = 150;
624 }
625
626 memcpy(levt, &lapic_clockevent, sizeof(*levt));
627 levt->cpumask = cpumask_of(smp_processor_id());
628
629 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
630 levt->name = "lapic-deadline";
631 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
632 CLOCK_EVT_FEAT_DUMMY);
633 levt->set_next_event = lapic_next_deadline;
634 clockevents_config_and_register(levt,
635 tsc_khz * (1000 / TSC_DIVISOR),
636 0xF, ~0UL);
637 } else
638 clockevents_register_device(levt);
639}
640
641/*
642 * Install the updated TSC frequency from recalibration at the TSC
643 * deadline clockevent devices.
644 */
645static void __lapic_update_tsc_freq(void *info)
646{
647 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
648
649 if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
650 return;
651
652 clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
653}
654
655void lapic_update_tsc_freq(void)
656{
657 /*
658 * The clockevent device's ->mult and ->shift can both be
659 * changed. In order to avoid races, schedule the frequency
660 * update code on each CPU.
661 */
662 on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
663}
664
665/*
666 * In this functions we calibrate APIC bus clocks to the external timer.
667 *
668 * We want to do the calibration only once since we want to have local timer
669 * irqs synchronous. CPUs connected by the same APIC bus have the very same bus
670 * frequency.
671 *
672 * This was previously done by reading the PIT/HPET and waiting for a wrap
673 * around to find out, that a tick has elapsed. I have a box, where the PIT
674 * readout is broken, so it never gets out of the wait loop again. This was
675 * also reported by others.
676 *
677 * Monitoring the jiffies value is inaccurate and the clockevents
678 * infrastructure allows us to do a simple substitution of the interrupt
679 * handler.
680 *
681 * The calibration routine also uses the pm_timer when possible, as the PIT
682 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
683 * back to normal later in the boot process).
684 */
685
686#define LAPIC_CAL_LOOPS (HZ/10)
687
688static __initdata int lapic_cal_loops = -1;
689static __initdata long lapic_cal_t1, lapic_cal_t2;
690static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
691static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
692static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
693
694/*
695 * Temporary interrupt handler and polled calibration function.
696 */
697static void __init lapic_cal_handler(struct clock_event_device *dev)
698{
699 unsigned long long tsc = 0;
700 long tapic = apic_read(APIC_TMCCT);
701 unsigned long pm = acpi_pm_read_early();
702
703 if (boot_cpu_has(X86_FEATURE_TSC))
704 tsc = rdtsc();
705
706 switch (lapic_cal_loops++) {
707 case 0:
708 lapic_cal_t1 = tapic;
709 lapic_cal_tsc1 = tsc;
710 lapic_cal_pm1 = pm;
711 lapic_cal_j1 = jiffies;
712 break;
713
714 case LAPIC_CAL_LOOPS:
715 lapic_cal_t2 = tapic;
716 lapic_cal_tsc2 = tsc;
717 if (pm < lapic_cal_pm1)
718 pm += ACPI_PM_OVRRUN;
719 lapic_cal_pm2 = pm;
720 lapic_cal_j2 = jiffies;
721 break;
722 }
723}
724
725static int __init
726calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
727{
728 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
729 const long pm_thresh = pm_100ms / 100;
730 unsigned long mult;
731 u64 res;
732
733#ifndef CONFIG_X86_PM_TIMER
734 return -1;
735#endif
736
737 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
738
739 /* Check, if the PM timer is available */
740 if (!deltapm)
741 return -1;
742
743 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
744
745 if (deltapm > (pm_100ms - pm_thresh) &&
746 deltapm < (pm_100ms + pm_thresh)) {
747 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
748 return 0;
749 }
750
751 res = (((u64)deltapm) * mult) >> 22;
752 do_div(res, 1000000);
753 pr_warn("APIC calibration not consistent "
754 "with PM-Timer: %ldms instead of 100ms\n", (long)res);
755
756 /* Correct the lapic counter value */
757 res = (((u64)(*delta)) * pm_100ms);
758 do_div(res, deltapm);
759 pr_info("APIC delta adjusted to PM-Timer: "
760 "%lu (%ld)\n", (unsigned long)res, *delta);
761 *delta = (long)res;
762
763 /* Correct the tsc counter value */
764 if (boot_cpu_has(X86_FEATURE_TSC)) {
765 res = (((u64)(*deltatsc)) * pm_100ms);
766 do_div(res, deltapm);
767 apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
768 "PM-Timer: %lu (%ld)\n",
769 (unsigned long)res, *deltatsc);
770 *deltatsc = (long)res;
771 }
772
773 return 0;
774}
775
776static int __init lapic_init_clockevent(void)
777{
778 if (!lapic_timer_period)
779 return -1;
780
781 /* Calculate the scaled math multiplication factor */
782 lapic_clockevent.mult = div_sc(lapic_timer_period/APIC_DIVISOR,
783 TICK_NSEC, lapic_clockevent.shift);
784 lapic_clockevent.max_delta_ns =
785 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
786 lapic_clockevent.max_delta_ticks = 0x7FFFFFFF;
787 lapic_clockevent.min_delta_ns =
788 clockevent_delta2ns(0xF, &lapic_clockevent);
789 lapic_clockevent.min_delta_ticks = 0xF;
790
791 return 0;
792}
793
794bool __init apic_needs_pit(void)
795{
796 /*
797 * If the frequencies are not known, PIT is required for both TSC
798 * and apic timer calibration.
799 */
800 if (!tsc_khz || !cpu_khz)
801 return true;
802
803 /* Is there an APIC at all or is it disabled? */
804 if (!boot_cpu_has(X86_FEATURE_APIC) || disable_apic)
805 return true;
806
807 /*
808 * If interrupt delivery mode is legacy PIC or virtual wire without
809 * configuration, the local APIC timer wont be set up. Make sure
810 * that the PIT is initialized.
811 */
812 if (apic_intr_mode == APIC_PIC ||
813 apic_intr_mode == APIC_VIRTUAL_WIRE_NO_CONFIG)
814 return true;
815
816 /* Virt guests may lack ARAT, but still have DEADLINE */
817 if (!boot_cpu_has(X86_FEATURE_ARAT))
818 return true;
819
820 /* Deadline timer is based on TSC so no further PIT action required */
821 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
822 return false;
823
824 /* APIC timer disabled? */
825 if (disable_apic_timer)
826 return true;
827 /*
828 * The APIC timer frequency is known already, no PIT calibration
829 * required. If unknown, let the PIT be initialized.
830 */
831 return lapic_timer_period == 0;
832}
833
834static int __init calibrate_APIC_clock(void)
835{
836 struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
837 u64 tsc_perj = 0, tsc_start = 0;
838 unsigned long jif_start;
839 unsigned long deltaj;
840 long delta, deltatsc;
841 int pm_referenced = 0;
842
843 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
844 return 0;
845
846 /*
847 * Check if lapic timer has already been calibrated by platform
848 * specific routine, such as tsc calibration code. If so just fill
849 * in the clockevent structure and return.
850 */
851 if (!lapic_init_clockevent()) {
852 apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
853 lapic_timer_period);
854 /*
855 * Direct calibration methods must have an always running
856 * local APIC timer, no need for broadcast timer.
857 */
858 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
859 return 0;
860 }
861
862 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
863 "calibrating APIC timer ...\n");
864
865 /*
866 * There are platforms w/o global clockevent devices. Instead of
867 * making the calibration conditional on that, use a polling based
868 * approach everywhere.
869 */
870 local_irq_disable();
871
872 /*
873 * Setup the APIC counter to maximum. There is no way the lapic
874 * can underflow in the 100ms detection time frame
875 */
876 __setup_APIC_LVTT(0xffffffff, 0, 0);
877
878 /*
879 * Methods to terminate the calibration loop:
880 * 1) Global clockevent if available (jiffies)
881 * 2) TSC if available and frequency is known
882 */
883 jif_start = READ_ONCE(jiffies);
884
885 if (tsc_khz) {
886 tsc_start = rdtsc();
887 tsc_perj = div_u64((u64)tsc_khz * 1000, HZ);
888 }
889
890 /*
891 * Enable interrupts so the tick can fire, if a global
892 * clockevent device is available
893 */
894 local_irq_enable();
895
896 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) {
897 /* Wait for a tick to elapse */
898 while (1) {
899 if (tsc_khz) {
900 u64 tsc_now = rdtsc();
901 if ((tsc_now - tsc_start) >= tsc_perj) {
902 tsc_start += tsc_perj;
903 break;
904 }
905 } else {
906 unsigned long jif_now = READ_ONCE(jiffies);
907
908 if (time_after(jif_now, jif_start)) {
909 jif_start = jif_now;
910 break;
911 }
912 }
913 cpu_relax();
914 }
915
916 /* Invoke the calibration routine */
917 local_irq_disable();
918 lapic_cal_handler(NULL);
919 local_irq_enable();
920 }
921
922 local_irq_disable();
923
924 /* Build delta t1-t2 as apic timer counts down */
925 delta = lapic_cal_t1 - lapic_cal_t2;
926 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
927
928 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
929
930 /* we trust the PM based calibration if possible */
931 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
932 &delta, &deltatsc);
933
934 lapic_timer_period = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
935 lapic_init_clockevent();
936
937 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
938 apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
939 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
940 lapic_timer_period);
941
942 if (boot_cpu_has(X86_FEATURE_TSC)) {
943 apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
944 "%ld.%04ld MHz.\n",
945 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
946 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
947 }
948
949 apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
950 "%u.%04u MHz.\n",
951 lapic_timer_period / (1000000 / HZ),
952 lapic_timer_period % (1000000 / HZ));
953
954 /*
955 * Do a sanity check on the APIC calibration result
956 */
957 if (lapic_timer_period < (1000000 / HZ)) {
958 local_irq_enable();
959 pr_warn("APIC frequency too slow, disabling apic timer\n");
960 return -1;
961 }
962
963 levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
964
965 /*
966 * PM timer calibration failed or not turned on so lets try APIC
967 * timer based calibration, if a global clockevent device is
968 * available.
969 */
970 if (!pm_referenced && global_clock_event) {
971 apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
972
973 /*
974 * Setup the apic timer manually
975 */
976 levt->event_handler = lapic_cal_handler;
977 lapic_timer_set_periodic(levt);
978 lapic_cal_loops = -1;
979
980 /* Let the interrupts run */
981 local_irq_enable();
982
983 while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
984 cpu_relax();
985
986 /* Stop the lapic timer */
987 local_irq_disable();
988 lapic_timer_shutdown(levt);
989
990 /* Jiffies delta */
991 deltaj = lapic_cal_j2 - lapic_cal_j1;
992 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
993
994 /* Check, if the jiffies result is consistent */
995 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
996 apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
997 else
998 levt->features |= CLOCK_EVT_FEAT_DUMMY;
999 }
1000 local_irq_enable();
1001
1002 if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
1003 pr_warn("APIC timer disabled due to verification failure\n");
1004 return -1;
1005 }
1006
1007 return 0;
1008}
1009
1010/*
1011 * Setup the boot APIC
1012 *
1013 * Calibrate and verify the result.
1014 */
1015void __init setup_boot_APIC_clock(void)
1016{
1017 /*
1018 * The local apic timer can be disabled via the kernel
1019 * commandline or from the CPU detection code. Register the lapic
1020 * timer as a dummy clock event source on SMP systems, so the
1021 * broadcast mechanism is used. On UP systems simply ignore it.
1022 */
1023 if (disable_apic_timer) {
1024 pr_info("Disabling APIC timer\n");
1025 /* No broadcast on UP ! */
1026 if (num_possible_cpus() > 1) {
1027 lapic_clockevent.mult = 1;
1028 setup_APIC_timer();
1029 }
1030 return;
1031 }
1032
1033 if (calibrate_APIC_clock()) {
1034 /* No broadcast on UP ! */
1035 if (num_possible_cpus() > 1)
1036 setup_APIC_timer();
1037 return;
1038 }
1039
1040 /*
1041 * If nmi_watchdog is set to IO_APIC, we need the
1042 * PIT/HPET going. Otherwise register lapic as a dummy
1043 * device.
1044 */
1045 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
1046
1047 /* Setup the lapic or request the broadcast */
1048 setup_APIC_timer();
1049 amd_e400_c1e_apic_setup();
1050}
1051
1052void setup_secondary_APIC_clock(void)
1053{
1054 setup_APIC_timer();
1055 amd_e400_c1e_apic_setup();
1056}
1057
1058/*
1059 * The guts of the apic timer interrupt
1060 */
1061static void local_apic_timer_interrupt(void)
1062{
1063 struct clock_event_device *evt = this_cpu_ptr(&lapic_events);
1064
1065 /*
1066 * Normally we should not be here till LAPIC has been initialized but
1067 * in some cases like kdump, its possible that there is a pending LAPIC
1068 * timer interrupt from previous kernel's context and is delivered in
1069 * new kernel the moment interrupts are enabled.
1070 *
1071 * Interrupts are enabled early and LAPIC is setup much later, hence
1072 * its possible that when we get here evt->event_handler is NULL.
1073 * Check for event_handler being NULL and discard the interrupt as
1074 * spurious.
1075 */
1076 if (!evt->event_handler) {
1077 pr_warn("Spurious LAPIC timer interrupt on cpu %d\n",
1078 smp_processor_id());
1079 /* Switch it off */
1080 lapic_timer_shutdown(evt);
1081 return;
1082 }
1083
1084 /*
1085 * the NMI deadlock-detector uses this.
1086 */
1087 inc_irq_stat(apic_timer_irqs);
1088
1089 evt->event_handler(evt);
1090}
1091
1092/*
1093 * Local APIC timer interrupt. This is the most natural way for doing
1094 * local interrupts, but local timer interrupts can be emulated by
1095 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
1096 *
1097 * [ if a single-CPU system runs an SMP kernel then we call the local
1098 * interrupt as well. Thus we cannot inline the local irq ... ]
1099 */
1100DEFINE_IDTENTRY_SYSVEC(sysvec_apic_timer_interrupt)
1101{
1102 struct pt_regs *old_regs = set_irq_regs(regs);
1103
1104 ack_APIC_irq();
1105 trace_local_timer_entry(LOCAL_TIMER_VECTOR);
1106 local_apic_timer_interrupt();
1107 trace_local_timer_exit(LOCAL_TIMER_VECTOR);
1108
1109 set_irq_regs(old_regs);
1110}
1111
1112int setup_profiling_timer(unsigned int multiplier)
1113{
1114 return -EINVAL;
1115}
1116
1117/*
1118 * Local APIC start and shutdown
1119 */
1120
1121/**
1122 * clear_local_APIC - shutdown the local APIC
1123 *
1124 * This is called, when a CPU is disabled and before rebooting, so the state of
1125 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
1126 * leftovers during boot.
1127 */
1128void clear_local_APIC(void)
1129{
1130 int maxlvt;
1131 u32 v;
1132
1133 /* APIC hasn't been mapped yet */
1134 if (!x2apic_mode && !apic_phys)
1135 return;
1136
1137 maxlvt = lapic_get_maxlvt();
1138 /*
1139 * Masking an LVT entry can trigger a local APIC error
1140 * if the vector is zero. Mask LVTERR first to prevent this.
1141 */
1142 if (maxlvt >= 3) {
1143 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
1144 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
1145 }
1146 /*
1147 * Careful: we have to set masks only first to deassert
1148 * any level-triggered sources.
1149 */
1150 v = apic_read(APIC_LVTT);
1151 apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
1152 v = apic_read(APIC_LVT0);
1153 apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1154 v = apic_read(APIC_LVT1);
1155 apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1156 if (maxlvt >= 4) {
1157 v = apic_read(APIC_LVTPC);
1158 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1159 }
1160
1161 /* lets not touch this if we didn't frob it */
1162#ifdef CONFIG_X86_THERMAL_VECTOR
1163 if (maxlvt >= 5) {
1164 v = apic_read(APIC_LVTTHMR);
1165 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1166 }
1167#endif
1168#ifdef CONFIG_X86_MCE_INTEL
1169 if (maxlvt >= 6) {
1170 v = apic_read(APIC_LVTCMCI);
1171 if (!(v & APIC_LVT_MASKED))
1172 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1173 }
1174#endif
1175
1176 /*
1177 * Clean APIC state for other OSs:
1178 */
1179 apic_write(APIC_LVTT, APIC_LVT_MASKED);
1180 apic_write(APIC_LVT0, APIC_LVT_MASKED);
1181 apic_write(APIC_LVT1, APIC_LVT_MASKED);
1182 if (maxlvt >= 3)
1183 apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1184 if (maxlvt >= 4)
1185 apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1186
1187 /* Integrated APIC (!82489DX) ? */
1188 if (lapic_is_integrated()) {
1189 if (maxlvt > 3)
1190 /* Clear ESR due to Pentium errata 3AP and 11AP */
1191 apic_write(APIC_ESR, 0);
1192 apic_read(APIC_ESR);
1193 }
1194}
1195
1196/**
1197 * apic_soft_disable - Clears and software disables the local APIC on hotplug
1198 *
1199 * Contrary to disable_local_APIC() this does not touch the enable bit in
1200 * MSR_IA32_APICBASE. Clearing that bit on systems based on the 3 wire APIC
1201 * bus would require a hardware reset as the APIC would lose track of bus
1202 * arbitration. On systems with FSB delivery APICBASE could be disabled,
1203 * but it has to be guaranteed that no interrupt is sent to the APIC while
1204 * in that state and it's not clear from the SDM whether it still responds
1205 * to INIT/SIPI messages. Stay on the safe side and use software disable.
1206 */
1207void apic_soft_disable(void)
1208{
1209 u32 value;
1210
1211 clear_local_APIC();
1212
1213 /* Soft disable APIC (implies clearing of registers for 82489DX!). */
1214 value = apic_read(APIC_SPIV);
1215 value &= ~APIC_SPIV_APIC_ENABLED;
1216 apic_write(APIC_SPIV, value);
1217}
1218
1219/**
1220 * disable_local_APIC - clear and disable the local APIC
1221 */
1222void disable_local_APIC(void)
1223{
1224 /* APIC hasn't been mapped yet */
1225 if (!x2apic_mode && !apic_phys)
1226 return;
1227
1228 apic_soft_disable();
1229
1230#ifdef CONFIG_X86_32
1231 /*
1232 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1233 * restore the disabled state.
1234 */
1235 if (enabled_via_apicbase) {
1236 unsigned int l, h;
1237
1238 rdmsr(MSR_IA32_APICBASE, l, h);
1239 l &= ~MSR_IA32_APICBASE_ENABLE;
1240 wrmsr(MSR_IA32_APICBASE, l, h);
1241 }
1242#endif
1243}
1244
1245/*
1246 * If Linux enabled the LAPIC against the BIOS default disable it down before
1247 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
1248 * not power-off. Additionally clear all LVT entries before disable_local_APIC
1249 * for the case where Linux didn't enable the LAPIC.
1250 */
1251void lapic_shutdown(void)
1252{
1253 unsigned long flags;
1254
1255 if (!boot_cpu_has(X86_FEATURE_APIC) && !apic_from_smp_config())
1256 return;
1257
1258 local_irq_save(flags);
1259
1260#ifdef CONFIG_X86_32
1261 if (!enabled_via_apicbase)
1262 clear_local_APIC();
1263 else
1264#endif
1265 disable_local_APIC();
1266
1267
1268 local_irq_restore(flags);
1269}
1270
1271/**
1272 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1273 */
1274void __init sync_Arb_IDs(void)
1275{
1276 /*
1277 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1278 * needed on AMD.
1279 */
1280 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1281 return;
1282
1283 /*
1284 * Wait for idle.
1285 */
1286 apic_wait_icr_idle();
1287
1288 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1289 apic_write(APIC_ICR, APIC_DEST_ALLINC |
1290 APIC_INT_LEVELTRIG | APIC_DM_INIT);
1291}
1292
1293enum apic_intr_mode_id apic_intr_mode __ro_after_init;
1294
1295static int __init __apic_intr_mode_select(void)
1296{
1297 /* Check kernel option */
1298 if (disable_apic) {
1299 pr_info("APIC disabled via kernel command line\n");
1300 return APIC_PIC;
1301 }
1302
1303 /* Check BIOS */
1304#ifdef CONFIG_X86_64
1305 /* On 64-bit, the APIC must be integrated, Check local APIC only */
1306 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1307 disable_apic = 1;
1308 pr_info("APIC disabled by BIOS\n");
1309 return APIC_PIC;
1310 }
1311#else
1312 /* On 32-bit, the APIC may be integrated APIC or 82489DX */
1313
1314 /* Neither 82489DX nor integrated APIC ? */
1315 if (!boot_cpu_has(X86_FEATURE_APIC) && !smp_found_config) {
1316 disable_apic = 1;
1317 return APIC_PIC;
1318 }
1319
1320 /* If the BIOS pretends there is an integrated APIC ? */
1321 if (!boot_cpu_has(X86_FEATURE_APIC) &&
1322 APIC_INTEGRATED(boot_cpu_apic_version)) {
1323 disable_apic = 1;
1324 pr_err(FW_BUG "Local APIC %d not detected, force emulation\n",
1325 boot_cpu_physical_apicid);
1326 return APIC_PIC;
1327 }
1328#endif
1329
1330 /* Check MP table or ACPI MADT configuration */
1331 if (!smp_found_config) {
1332 disable_ioapic_support();
1333 if (!acpi_lapic) {
1334 pr_info("APIC: ACPI MADT or MP tables are not detected\n");
1335 return APIC_VIRTUAL_WIRE_NO_CONFIG;
1336 }
1337 return APIC_VIRTUAL_WIRE;
1338 }
1339
1340#ifdef CONFIG_SMP
1341 /* If SMP should be disabled, then really disable it! */
1342 if (!setup_max_cpus) {
1343 pr_info("APIC: SMP mode deactivated\n");
1344 return APIC_SYMMETRIC_IO_NO_ROUTING;
1345 }
1346
1347 if (read_apic_id() != boot_cpu_physical_apicid) {
1348 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
1349 read_apic_id(), boot_cpu_physical_apicid);
1350 /* Or can we switch back to PIC here? */
1351 }
1352#endif
1353
1354 return APIC_SYMMETRIC_IO;
1355}
1356
1357/* Select the interrupt delivery mode for the BSP */
1358void __init apic_intr_mode_select(void)
1359{
1360 apic_intr_mode = __apic_intr_mode_select();
1361}
1362
1363/*
1364 * An initial setup of the virtual wire mode.
1365 */
1366void __init init_bsp_APIC(void)
1367{
1368 unsigned int value;
1369
1370 /*
1371 * Don't do the setup now if we have a SMP BIOS as the
1372 * through-I/O-APIC virtual wire mode might be active.
1373 */
1374 if (smp_found_config || !boot_cpu_has(X86_FEATURE_APIC))
1375 return;
1376
1377 /*
1378 * Do not trust the local APIC being empty at bootup.
1379 */
1380 clear_local_APIC();
1381
1382 /*
1383 * Enable APIC.
1384 */
1385 value = apic_read(APIC_SPIV);
1386 value &= ~APIC_VECTOR_MASK;
1387 value |= APIC_SPIV_APIC_ENABLED;
1388
1389#ifdef CONFIG_X86_32
1390 /* This bit is reserved on P4/Xeon and should be cleared */
1391 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1392 (boot_cpu_data.x86 == 15))
1393 value &= ~APIC_SPIV_FOCUS_DISABLED;
1394 else
1395#endif
1396 value |= APIC_SPIV_FOCUS_DISABLED;
1397 value |= SPURIOUS_APIC_VECTOR;
1398 apic_write(APIC_SPIV, value);
1399
1400 /*
1401 * Set up the virtual wire mode.
1402 */
1403 apic_write(APIC_LVT0, APIC_DM_EXTINT);
1404 value = APIC_DM_NMI;
1405 if (!lapic_is_integrated()) /* 82489DX */
1406 value |= APIC_LVT_LEVEL_TRIGGER;
1407 if (apic_extnmi == APIC_EXTNMI_NONE)
1408 value |= APIC_LVT_MASKED;
1409 apic_write(APIC_LVT1, value);
1410}
1411
1412static void __init apic_bsp_setup(bool upmode);
1413
1414/* Init the interrupt delivery mode for the BSP */
1415void __init apic_intr_mode_init(void)
1416{
1417 bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
1418
1419 switch (apic_intr_mode) {
1420 case APIC_PIC:
1421 pr_info("APIC: Keep in PIC mode(8259)\n");
1422 return;
1423 case APIC_VIRTUAL_WIRE:
1424 pr_info("APIC: Switch to virtual wire mode setup\n");
1425 default_setup_apic_routing();
1426 break;
1427 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1428 pr_info("APIC: Switch to virtual wire mode setup with no configuration\n");
1429 upmode = true;
1430 default_setup_apic_routing();
1431 break;
1432 case APIC_SYMMETRIC_IO:
1433 pr_info("APIC: Switch to symmetric I/O mode setup\n");
1434 default_setup_apic_routing();
1435 break;
1436 case APIC_SYMMETRIC_IO_NO_ROUTING:
1437 pr_info("APIC: Switch to symmetric I/O mode setup in no SMP routine\n");
1438 break;
1439 }
1440
1441 if (x86_platform.apic_post_init)
1442 x86_platform.apic_post_init();
1443
1444 apic_bsp_setup(upmode);
1445}
1446
1447static void lapic_setup_esr(void)
1448{
1449 unsigned int oldvalue, value, maxlvt;
1450
1451 if (!lapic_is_integrated()) {
1452 pr_info("No ESR for 82489DX.\n");
1453 return;
1454 }
1455
1456 if (apic->disable_esr) {
1457 /*
1458 * Something untraceable is creating bad interrupts on
1459 * secondary quads ... for the moment, just leave the
1460 * ESR disabled - we can't do anything useful with the
1461 * errors anyway - mbligh
1462 */
1463 pr_info("Leaving ESR disabled.\n");
1464 return;
1465 }
1466
1467 maxlvt = lapic_get_maxlvt();
1468 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
1469 apic_write(APIC_ESR, 0);
1470 oldvalue = apic_read(APIC_ESR);
1471
1472 /* enables sending errors */
1473 value = ERROR_APIC_VECTOR;
1474 apic_write(APIC_LVTERR, value);
1475
1476 /*
1477 * spec says clear errors after enabling vector.
1478 */
1479 if (maxlvt > 3)
1480 apic_write(APIC_ESR, 0);
1481 value = apic_read(APIC_ESR);
1482 if (value != oldvalue)
1483 apic_printk(APIC_VERBOSE, "ESR value before enabling "
1484 "vector: 0x%08x after: 0x%08x\n",
1485 oldvalue, value);
1486}
1487
1488#define APIC_IR_REGS APIC_ISR_NR
1489#define APIC_IR_BITS (APIC_IR_REGS * 32)
1490#define APIC_IR_MAPSIZE (APIC_IR_BITS / BITS_PER_LONG)
1491
1492union apic_ir {
1493 unsigned long map[APIC_IR_MAPSIZE];
1494 u32 regs[APIC_IR_REGS];
1495};
1496
1497static bool apic_check_and_ack(union apic_ir *irr, union apic_ir *isr)
1498{
1499 int i, bit;
1500
1501 /* Read the IRRs */
1502 for (i = 0; i < APIC_IR_REGS; i++)
1503 irr->regs[i] = apic_read(APIC_IRR + i * 0x10);
1504
1505 /* Read the ISRs */
1506 for (i = 0; i < APIC_IR_REGS; i++)
1507 isr->regs[i] = apic_read(APIC_ISR + i * 0x10);
1508
1509 /*
1510 * If the ISR map is not empty. ACK the APIC and run another round
1511 * to verify whether a pending IRR has been unblocked and turned
1512 * into a ISR.
1513 */
1514 if (!bitmap_empty(isr->map, APIC_IR_BITS)) {
1515 /*
1516 * There can be multiple ISR bits set when a high priority
1517 * interrupt preempted a lower priority one. Issue an ACK
1518 * per set bit.
1519 */
1520 for_each_set_bit(bit, isr->map, APIC_IR_BITS)
1521 ack_APIC_irq();
1522 return true;
1523 }
1524
1525 return !bitmap_empty(irr->map, APIC_IR_BITS);
1526}
1527
1528/*
1529 * After a crash, we no longer service the interrupts and a pending
1530 * interrupt from previous kernel might still have ISR bit set.
1531 *
1532 * Most probably by now the CPU has serviced that pending interrupt and it
1533 * might not have done the ack_APIC_irq() because it thought, interrupt
1534 * came from i8259 as ExtInt. LAPIC did not get EOI so it does not clear
1535 * the ISR bit and cpu thinks it has already serviced the interrupt. Hence
1536 * a vector might get locked. It was noticed for timer irq (vector
1537 * 0x31). Issue an extra EOI to clear ISR.
1538 *
1539 * If there are pending IRR bits they turn into ISR bits after a higher
1540 * priority ISR bit has been acked.
1541 */
1542static void apic_pending_intr_clear(void)
1543{
1544 union apic_ir irr, isr;
1545 unsigned int i;
1546
1547 /* 512 loops are way oversized and give the APIC a chance to obey. */
1548 for (i = 0; i < 512; i++) {
1549 if (!apic_check_and_ack(&irr, &isr))
1550 return;
1551 }
1552 /* Dump the IRR/ISR content if that failed */
1553 pr_warn("APIC: Stale IRR: %256pb ISR: %256pb\n", irr.map, isr.map);
1554}
1555
1556/**
1557 * setup_local_APIC - setup the local APIC
1558 *
1559 * Used to setup local APIC while initializing BSP or bringing up APs.
1560 * Always called with preemption disabled.
1561 */
1562static void setup_local_APIC(void)
1563{
1564 int cpu = smp_processor_id();
1565 unsigned int value;
1566
1567 if (disable_apic) {
1568 disable_ioapic_support();
1569 return;
1570 }
1571
1572 /*
1573 * If this comes from kexec/kcrash the APIC might be enabled in
1574 * SPIV. Soft disable it before doing further initialization.
1575 */
1576 value = apic_read(APIC_SPIV);
1577 value &= ~APIC_SPIV_APIC_ENABLED;
1578 apic_write(APIC_SPIV, value);
1579
1580#ifdef CONFIG_X86_32
1581 /* Pound the ESR really hard over the head with a big hammer - mbligh */
1582 if (lapic_is_integrated() && apic->disable_esr) {
1583 apic_write(APIC_ESR, 0);
1584 apic_write(APIC_ESR, 0);
1585 apic_write(APIC_ESR, 0);
1586 apic_write(APIC_ESR, 0);
1587 }
1588#endif
1589 /*
1590 * Double-check whether this APIC is really registered.
1591 * This is meaningless in clustered apic mode, so we skip it.
1592 */
1593 BUG_ON(!apic->apic_id_registered());
1594
1595 /*
1596 * Intel recommends to set DFR, LDR and TPR before enabling
1597 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
1598 * document number 292116). So here it goes...
1599 */
1600 apic->init_apic_ldr();
1601
1602#ifdef CONFIG_X86_32
1603 if (apic->dest_mode_logical) {
1604 int logical_apicid, ldr_apicid;
1605
1606 /*
1607 * APIC LDR is initialized. If logical_apicid mapping was
1608 * initialized during get_smp_config(), make sure it matches
1609 * the actual value.
1610 */
1611 logical_apicid = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
1612 ldr_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1613 if (logical_apicid != BAD_APICID)
1614 WARN_ON(logical_apicid != ldr_apicid);
1615 /* Always use the value from LDR. */
1616 early_per_cpu(x86_cpu_to_logical_apicid, cpu) = ldr_apicid;
1617 }
1618#endif
1619
1620 /*
1621 * Set Task Priority to 'accept all except vectors 0-31'. An APIC
1622 * vector in the 16-31 range could be delivered if TPR == 0, but we
1623 * would think it's an exception and terrible things will happen. We
1624 * never change this later on.
1625 */
1626 value = apic_read(APIC_TASKPRI);
1627 value &= ~APIC_TPRI_MASK;
1628 value |= 0x10;
1629 apic_write(APIC_TASKPRI, value);
1630
1631 /* Clear eventually stale ISR/IRR bits */
1632 apic_pending_intr_clear();
1633
1634 /*
1635 * Now that we are all set up, enable the APIC
1636 */
1637 value = apic_read(APIC_SPIV);
1638 value &= ~APIC_VECTOR_MASK;
1639 /*
1640 * Enable APIC
1641 */
1642 value |= APIC_SPIV_APIC_ENABLED;
1643
1644#ifdef CONFIG_X86_32
1645 /*
1646 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1647 * certain networking cards. If high frequency interrupts are
1648 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1649 * entry is masked/unmasked at a high rate as well then sooner or
1650 * later IOAPIC line gets 'stuck', no more interrupts are received
1651 * from the device. If focus CPU is disabled then the hang goes
1652 * away, oh well :-(
1653 *
1654 * [ This bug can be reproduced easily with a level-triggered
1655 * PCI Ne2000 networking cards and PII/PIII processors, dual
1656 * BX chipset. ]
1657 */
1658 /*
1659 * Actually disabling the focus CPU check just makes the hang less
1660 * frequent as it makes the interrupt distribution model be more
1661 * like LRU than MRU (the short-term load is more even across CPUs).
1662 */
1663
1664 /*
1665 * - enable focus processor (bit==0)
1666 * - 64bit mode always use processor focus
1667 * so no need to set it
1668 */
1669 value &= ~APIC_SPIV_FOCUS_DISABLED;
1670#endif
1671
1672 /*
1673 * Set spurious IRQ vector
1674 */
1675 value |= SPURIOUS_APIC_VECTOR;
1676 apic_write(APIC_SPIV, value);
1677
1678 perf_events_lapic_init();
1679
1680 /*
1681 * Set up LVT0, LVT1:
1682 *
1683 * set up through-local-APIC on the boot CPU's LINT0. This is not
1684 * strictly necessary in pure symmetric-IO mode, but sometimes
1685 * we delegate interrupts to the 8259A.
1686 */
1687 /*
1688 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1689 */
1690 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1691 if (!cpu && (pic_mode || !value || skip_ioapic_setup)) {
1692 value = APIC_DM_EXTINT;
1693 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1694 } else {
1695 value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1696 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1697 }
1698 apic_write(APIC_LVT0, value);
1699
1700 /*
1701 * Only the BSP sees the LINT1 NMI signal by default. This can be
1702 * modified by apic_extnmi= boot option.
1703 */
1704 if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1705 apic_extnmi == APIC_EXTNMI_ALL)
1706 value = APIC_DM_NMI;
1707 else
1708 value = APIC_DM_NMI | APIC_LVT_MASKED;
1709
1710 /* Is 82489DX ? */
1711 if (!lapic_is_integrated())
1712 value |= APIC_LVT_LEVEL_TRIGGER;
1713 apic_write(APIC_LVT1, value);
1714
1715#ifdef CONFIG_X86_MCE_INTEL
1716 /* Recheck CMCI information after local APIC is up on CPU #0 */
1717 if (!cpu)
1718 cmci_recheck();
1719#endif
1720}
1721
1722static void end_local_APIC_setup(void)
1723{
1724 lapic_setup_esr();
1725
1726#ifdef CONFIG_X86_32
1727 {
1728 unsigned int value;
1729 /* Disable the local apic timer */
1730 value = apic_read(APIC_LVTT);
1731 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1732 apic_write(APIC_LVTT, value);
1733 }
1734#endif
1735
1736 apic_pm_activate();
1737}
1738
1739/*
1740 * APIC setup function for application processors. Called from smpboot.c
1741 */
1742void apic_ap_setup(void)
1743{
1744 setup_local_APIC();
1745 end_local_APIC_setup();
1746}
1747
1748#ifdef CONFIG_X86_X2APIC
1749int x2apic_mode;
1750EXPORT_SYMBOL_GPL(x2apic_mode);
1751
1752enum {
1753 X2APIC_OFF,
1754 X2APIC_ON,
1755 X2APIC_DISABLED,
1756};
1757static int x2apic_state;
1758
1759static void __x2apic_disable(void)
1760{
1761 u64 msr;
1762
1763 if (!boot_cpu_has(X86_FEATURE_APIC))
1764 return;
1765
1766 rdmsrl(MSR_IA32_APICBASE, msr);
1767 if (!(msr & X2APIC_ENABLE))
1768 return;
1769 /* Disable xapic and x2apic first and then reenable xapic mode */
1770 wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1771 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1772 printk_once(KERN_INFO "x2apic disabled\n");
1773}
1774
1775static void __x2apic_enable(void)
1776{
1777 u64 msr;
1778
1779 rdmsrl(MSR_IA32_APICBASE, msr);
1780 if (msr & X2APIC_ENABLE)
1781 return;
1782 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1783 printk_once(KERN_INFO "x2apic enabled\n");
1784}
1785
1786static int __init setup_nox2apic(char *str)
1787{
1788 if (x2apic_enabled()) {
1789 int apicid = native_apic_msr_read(APIC_ID);
1790
1791 if (apicid >= 255) {
1792 pr_warn("Apicid: %08x, cannot enforce nox2apic\n",
1793 apicid);
1794 return 0;
1795 }
1796 pr_warn("x2apic already enabled.\n");
1797 __x2apic_disable();
1798 }
1799 setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1800 x2apic_state = X2APIC_DISABLED;
1801 x2apic_mode = 0;
1802 return 0;
1803}
1804early_param("nox2apic", setup_nox2apic);
1805
1806/* Called from cpu_init() to enable x2apic on (secondary) cpus */
1807void x2apic_setup(void)
1808{
1809 /*
1810 * If x2apic is not in ON state, disable it if already enabled
1811 * from BIOS.
1812 */
1813 if (x2apic_state != X2APIC_ON) {
1814 __x2apic_disable();
1815 return;
1816 }
1817 __x2apic_enable();
1818}
1819
1820static __init void x2apic_disable(void)
1821{
1822 u32 x2apic_id, state = x2apic_state;
1823
1824 x2apic_mode = 0;
1825 x2apic_state = X2APIC_DISABLED;
1826
1827 if (state != X2APIC_ON)
1828 return;
1829
1830 x2apic_id = read_apic_id();
1831 if (x2apic_id >= 255)
1832 panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1833
1834 __x2apic_disable();
1835 register_lapic_address(mp_lapic_addr);
1836}
1837
1838static __init void x2apic_enable(void)
1839{
1840 if (x2apic_state != X2APIC_OFF)
1841 return;
1842
1843 x2apic_mode = 1;
1844 x2apic_state = X2APIC_ON;
1845 __x2apic_enable();
1846}
1847
1848static __init void try_to_enable_x2apic(int remap_mode)
1849{
1850 if (x2apic_state == X2APIC_DISABLED)
1851 return;
1852
1853 if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1854 u32 apic_limit = 255;
1855
1856 /*
1857 * Using X2APIC without IR is not architecturally supported
1858 * on bare metal but may be supported in guests.
1859 */
1860 if (!x86_init.hyper.x2apic_available()) {
1861 pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1862 x2apic_disable();
1863 return;
1864 }
1865
1866 /*
1867 * If the hypervisor supports extended destination ID in
1868 * MSI, that increases the maximum APIC ID that can be
1869 * used for non-remapped IRQ domains.
1870 */
1871 if (x86_init.hyper.msi_ext_dest_id()) {
1872 virt_ext_dest_id = 1;
1873 apic_limit = 32767;
1874 }
1875
1876 /*
1877 * Without IR, all CPUs can be addressed by IOAPIC/MSI only
1878 * in physical mode, and CPUs with an APIC ID that cannot
1879 * be addressed must not be brought online.
1880 */
1881 x2apic_set_max_apicid(apic_limit);
1882 x2apic_phys = 1;
1883 }
1884 x2apic_enable();
1885}
1886
1887void __init check_x2apic(void)
1888{
1889 if (x2apic_enabled()) {
1890 pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1891 x2apic_mode = 1;
1892 x2apic_state = X2APIC_ON;
1893 } else if (!boot_cpu_has(X86_FEATURE_X2APIC)) {
1894 x2apic_state = X2APIC_DISABLED;
1895 }
1896}
1897#else /* CONFIG_X86_X2APIC */
1898static int __init validate_x2apic(void)
1899{
1900 if (!apic_is_x2apic_enabled())
1901 return 0;
1902 /*
1903 * Checkme: Can we simply turn off x2apic here instead of panic?
1904 */
1905 panic("BIOS has enabled x2apic but kernel doesn't support x2apic, please disable x2apic in BIOS.\n");
1906}
1907early_initcall(validate_x2apic);
1908
1909static inline void try_to_enable_x2apic(int remap_mode) { }
1910static inline void __x2apic_enable(void) { }
1911#endif /* !CONFIG_X86_X2APIC */
1912
1913void __init enable_IR_x2apic(void)
1914{
1915 unsigned long flags;
1916 int ret, ir_stat;
1917
1918 if (skip_ioapic_setup) {
1919 pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1920 return;
1921 }
1922
1923 ir_stat = irq_remapping_prepare();
1924 if (ir_stat < 0 && !x2apic_supported())
1925 return;
1926
1927 ret = save_ioapic_entries();
1928 if (ret) {
1929 pr_info("Saving IO-APIC state failed: %d\n", ret);
1930 return;
1931 }
1932
1933 local_irq_save(flags);
1934 legacy_pic->mask_all();
1935 mask_ioapic_entries();
1936
1937 /* If irq_remapping_prepare() succeeded, try to enable it */
1938 if (ir_stat >= 0)
1939 ir_stat = irq_remapping_enable();
1940 /* ir_stat contains the remap mode or an error code */
1941 try_to_enable_x2apic(ir_stat);
1942
1943 if (ir_stat < 0)
1944 restore_ioapic_entries();
1945 legacy_pic->restore_mask();
1946 local_irq_restore(flags);
1947}
1948
1949#ifdef CONFIG_X86_64
1950/*
1951 * Detect and enable local APICs on non-SMP boards.
1952 * Original code written by Keir Fraser.
1953 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1954 * not correctly set up (usually the APIC timer won't work etc.)
1955 */
1956static int __init detect_init_APIC(void)
1957{
1958 if (!boot_cpu_has(X86_FEATURE_APIC)) {
1959 pr_info("No local APIC present\n");
1960 return -1;
1961 }
1962
1963 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1964 return 0;
1965}
1966#else
1967
1968static int __init apic_verify(void)
1969{
1970 u32 features, h, l;
1971
1972 /*
1973 * The APIC feature bit should now be enabled
1974 * in `cpuid'
1975 */
1976 features = cpuid_edx(1);
1977 if (!(features & (1 << X86_FEATURE_APIC))) {
1978 pr_warn("Could not enable APIC!\n");
1979 return -1;
1980 }
1981 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1982 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1983
1984 /* The BIOS may have set up the APIC at some other address */
1985 if (boot_cpu_data.x86 >= 6) {
1986 rdmsr(MSR_IA32_APICBASE, l, h);
1987 if (l & MSR_IA32_APICBASE_ENABLE)
1988 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1989 }
1990
1991 pr_info("Found and enabled local APIC!\n");
1992 return 0;
1993}
1994
1995int __init apic_force_enable(unsigned long addr)
1996{
1997 u32 h, l;
1998
1999 if (disable_apic)
2000 return -1;
2001
2002 /*
2003 * Some BIOSes disable the local APIC in the APIC_BASE
2004 * MSR. This can only be done in software for Intel P6 or later
2005 * and AMD K7 (Model > 1) or later.
2006 */
2007 if (boot_cpu_data.x86 >= 6) {
2008 rdmsr(MSR_IA32_APICBASE, l, h);
2009 if (!(l & MSR_IA32_APICBASE_ENABLE)) {
2010 pr_info("Local APIC disabled by BIOS -- reenabling.\n");
2011 l &= ~MSR_IA32_APICBASE_BASE;
2012 l |= MSR_IA32_APICBASE_ENABLE | addr;
2013 wrmsr(MSR_IA32_APICBASE, l, h);
2014 enabled_via_apicbase = 1;
2015 }
2016 }
2017 return apic_verify();
2018}
2019
2020/*
2021 * Detect and initialize APIC
2022 */
2023static int __init detect_init_APIC(void)
2024{
2025 /* Disabled by kernel option? */
2026 if (disable_apic)
2027 return -1;
2028
2029 switch (boot_cpu_data.x86_vendor) {
2030 case X86_VENDOR_AMD:
2031 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
2032 (boot_cpu_data.x86 >= 15))
2033 break;
2034 goto no_apic;
2035 case X86_VENDOR_HYGON:
2036 break;
2037 case X86_VENDOR_INTEL:
2038 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
2039 (boot_cpu_data.x86 == 5 && boot_cpu_has(X86_FEATURE_APIC)))
2040 break;
2041 goto no_apic;
2042 default:
2043 goto no_apic;
2044 }
2045
2046 if (!boot_cpu_has(X86_FEATURE_APIC)) {
2047 /*
2048 * Over-ride BIOS and try to enable the local APIC only if
2049 * "lapic" specified.
2050 */
2051 if (!force_enable_local_apic) {
2052 pr_info("Local APIC disabled by BIOS -- "
2053 "you can enable it with \"lapic\"\n");
2054 return -1;
2055 }
2056 if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
2057 return -1;
2058 } else {
2059 if (apic_verify())
2060 return -1;
2061 }
2062
2063 apic_pm_activate();
2064
2065 return 0;
2066
2067no_apic:
2068 pr_info("No local APIC present or hardware disabled\n");
2069 return -1;
2070}
2071#endif
2072
2073/**
2074 * init_apic_mappings - initialize APIC mappings
2075 */
2076void __init init_apic_mappings(void)
2077{
2078 unsigned int new_apicid;
2079
2080 if (apic_validate_deadline_timer())
2081 pr_info("TSC deadline timer available\n");
2082
2083 if (x2apic_mode) {
2084 boot_cpu_physical_apicid = read_apic_id();
2085 return;
2086 }
2087
2088 /* If no local APIC can be found return early */
2089 if (!smp_found_config && detect_init_APIC()) {
2090 /* lets NOP'ify apic operations */
2091 pr_info("APIC: disable apic facility\n");
2092 apic_disable();
2093 } else {
2094 apic_phys = mp_lapic_addr;
2095
2096 /*
2097 * If the system has ACPI MADT tables or MP info, the LAPIC
2098 * address is already registered.
2099 */
2100 if (!acpi_lapic && !smp_found_config)
2101 register_lapic_address(apic_phys);
2102 }
2103
2104 /*
2105 * Fetch the APIC ID of the BSP in case we have a
2106 * default configuration (or the MP table is broken).
2107 */
2108 new_apicid = read_apic_id();
2109 if (boot_cpu_physical_apicid != new_apicid) {
2110 boot_cpu_physical_apicid = new_apicid;
2111 /*
2112 * yeah -- we lie about apic_version
2113 * in case if apic was disabled via boot option
2114 * but it's not a problem for SMP compiled kernel
2115 * since apic_intr_mode_select is prepared for such
2116 * a case and disable smp mode
2117 */
2118 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2119 }
2120}
2121
2122void __init register_lapic_address(unsigned long address)
2123{
2124 mp_lapic_addr = address;
2125
2126 if (!x2apic_mode) {
2127 set_fixmap_nocache(FIX_APIC_BASE, address);
2128 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
2129 APIC_BASE, address);
2130 }
2131 if (boot_cpu_physical_apicid == -1U) {
2132 boot_cpu_physical_apicid = read_apic_id();
2133 boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
2134 }
2135}
2136
2137/*
2138 * Local APIC interrupts
2139 */
2140
2141/*
2142 * Common handling code for spurious_interrupt and spurious_vector entry
2143 * points below. No point in allowing the compiler to inline it twice.
2144 */
2145static noinline void handle_spurious_interrupt(u8 vector)
2146{
2147 u32 v;
2148
2149 trace_spurious_apic_entry(vector);
2150
2151 inc_irq_stat(irq_spurious_count);
2152
2153 /*
2154 * If this is a spurious interrupt then do not acknowledge
2155 */
2156 if (vector == SPURIOUS_APIC_VECTOR) {
2157 /* See SDM vol 3 */
2158 pr_info("Spurious APIC interrupt (vector 0xFF) on CPU#%d, should never happen.\n",
2159 smp_processor_id());
2160 goto out;
2161 }
2162
2163 /*
2164 * If it is a vectored one, verify it's set in the ISR. If set,
2165 * acknowledge it.
2166 */
2167 v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
2168 if (v & (1 << (vector & 0x1f))) {
2169 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Acked\n",
2170 vector, smp_processor_id());
2171 ack_APIC_irq();
2172 } else {
2173 pr_info("Spurious interrupt (vector 0x%02x) on CPU#%d. Not pending!\n",
2174 vector, smp_processor_id());
2175 }
2176out:
2177 trace_spurious_apic_exit(vector);
2178}
2179
2180/**
2181 * spurious_interrupt - Catch all for interrupts raised on unused vectors
2182 * @regs: Pointer to pt_regs on stack
2183 * @vector: The vector number
2184 *
2185 * This is invoked from ASM entry code to catch all interrupts which
2186 * trigger on an entry which is routed to the common_spurious idtentry
2187 * point.
2188 */
2189DEFINE_IDTENTRY_IRQ(spurious_interrupt)
2190{
2191 handle_spurious_interrupt(vector);
2192}
2193
2194DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt)
2195{
2196 handle_spurious_interrupt(SPURIOUS_APIC_VECTOR);
2197}
2198
2199/*
2200 * This interrupt should never happen with our APIC/SMP architecture
2201 */
2202DEFINE_IDTENTRY_SYSVEC(sysvec_error_interrupt)
2203{
2204 static const char * const error_interrupt_reason[] = {
2205 "Send CS error", /* APIC Error Bit 0 */
2206 "Receive CS error", /* APIC Error Bit 1 */
2207 "Send accept error", /* APIC Error Bit 2 */
2208 "Receive accept error", /* APIC Error Bit 3 */
2209 "Redirectable IPI", /* APIC Error Bit 4 */
2210 "Send illegal vector", /* APIC Error Bit 5 */
2211 "Received illegal vector", /* APIC Error Bit 6 */
2212 "Illegal register address", /* APIC Error Bit 7 */
2213 };
2214 u32 v, i = 0;
2215
2216 trace_error_apic_entry(ERROR_APIC_VECTOR);
2217
2218 /* First tickle the hardware, only then report what went on. -- REW */
2219 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */
2220 apic_write(APIC_ESR, 0);
2221 v = apic_read(APIC_ESR);
2222 ack_APIC_irq();
2223 atomic_inc(&irq_err_count);
2224
2225 apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
2226 smp_processor_id(), v);
2227
2228 v &= 0xff;
2229 while (v) {
2230 if (v & 0x1)
2231 apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
2232 i++;
2233 v >>= 1;
2234 }
2235
2236 apic_printk(APIC_DEBUG, KERN_CONT "\n");
2237
2238 trace_error_apic_exit(ERROR_APIC_VECTOR);
2239}
2240
2241/**
2242 * connect_bsp_APIC - attach the APIC to the interrupt system
2243 */
2244static void __init connect_bsp_APIC(void)
2245{
2246#ifdef CONFIG_X86_32
2247 if (pic_mode) {
2248 /*
2249 * Do not trust the local APIC being empty at bootup.
2250 */
2251 clear_local_APIC();
2252 /*
2253 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
2254 * local APIC to INT and NMI lines.
2255 */
2256 apic_printk(APIC_VERBOSE, "leaving PIC mode, "
2257 "enabling APIC mode.\n");
2258 imcr_pic_to_apic();
2259 }
2260#endif
2261}
2262
2263/**
2264 * disconnect_bsp_APIC - detach the APIC from the interrupt system
2265 * @virt_wire_setup: indicates, whether virtual wire mode is selected
2266 *
2267 * Virtual wire mode is necessary to deliver legacy interrupts even when the
2268 * APIC is disabled.
2269 */
2270void disconnect_bsp_APIC(int virt_wire_setup)
2271{
2272 unsigned int value;
2273
2274#ifdef CONFIG_X86_32
2275 if (pic_mode) {
2276 /*
2277 * Put the board back into PIC mode (has an effect only on
2278 * certain older boards). Note that APIC interrupts, including
2279 * IPIs, won't work beyond this point! The only exception are
2280 * INIT IPIs.
2281 */
2282 apic_printk(APIC_VERBOSE, "disabling APIC mode, "
2283 "entering PIC mode.\n");
2284 imcr_apic_to_pic();
2285 return;
2286 }
2287#endif
2288
2289 /* Go back to Virtual Wire compatibility mode */
2290
2291 /* For the spurious interrupt use vector F, and enable it */
2292 value = apic_read(APIC_SPIV);
2293 value &= ~APIC_VECTOR_MASK;
2294 value |= APIC_SPIV_APIC_ENABLED;
2295 value |= 0xf;
2296 apic_write(APIC_SPIV, value);
2297
2298 if (!virt_wire_setup) {
2299 /*
2300 * For LVT0 make it edge triggered, active high,
2301 * external and enabled
2302 */
2303 value = apic_read(APIC_LVT0);
2304 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2305 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2306 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2307 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2308 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2309 apic_write(APIC_LVT0, value);
2310 } else {
2311 /* Disable LVT0 */
2312 apic_write(APIC_LVT0, APIC_LVT_MASKED);
2313 }
2314
2315 /*
2316 * For LVT1 make it edge triggered, active high,
2317 * nmi and enabled
2318 */
2319 value = apic_read(APIC_LVT1);
2320 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2321 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2322 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2323 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2324 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2325 apic_write(APIC_LVT1, value);
2326}
2327
2328/*
2329 * The number of allocated logical CPU IDs. Since logical CPU IDs are allocated
2330 * contiguously, it equals to current allocated max logical CPU ID plus 1.
2331 * All allocated CPU IDs should be in the [0, nr_logical_cpuids) range,
2332 * so the maximum of nr_logical_cpuids is nr_cpu_ids.
2333 *
2334 * NOTE: Reserve 0 for BSP.
2335 */
2336static int nr_logical_cpuids = 1;
2337
2338/*
2339 * Used to store mapping between logical CPU IDs and APIC IDs.
2340 */
2341static int cpuid_to_apicid[] = {
2342 [0 ... NR_CPUS - 1] = -1,
2343};
2344
2345bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
2346{
2347 return phys_id == cpuid_to_apicid[cpu];
2348}
2349
2350#ifdef CONFIG_SMP
2351/**
2352 * apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread
2353 * @apicid: APIC ID to check
2354 */
2355bool apic_id_is_primary_thread(unsigned int apicid)
2356{
2357 u32 mask;
2358
2359 if (smp_num_siblings == 1)
2360 return true;
2361 /* Isolate the SMT bit(s) in the APICID and check for 0 */
2362 mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
2363 return !(apicid & mask);
2364}
2365#endif
2366
2367/*
2368 * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
2369 * and cpuid_to_apicid[] synchronized.
2370 */
2371static int allocate_logical_cpuid(int apicid)
2372{
2373 int i;
2374
2375 /*
2376 * cpuid <-> apicid mapping is persistent, so when a cpu is up,
2377 * check if the kernel has allocated a cpuid for it.
2378 */
2379 for (i = 0; i < nr_logical_cpuids; i++) {
2380 if (cpuid_to_apicid[i] == apicid)
2381 return i;
2382 }
2383
2384 /* Allocate a new cpuid. */
2385 if (nr_logical_cpuids >= nr_cpu_ids) {
2386 WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
2387 "Processor %d/0x%x and the rest are ignored.\n",
2388 nr_cpu_ids, nr_logical_cpuids, apicid);
2389 return -EINVAL;
2390 }
2391
2392 cpuid_to_apicid[nr_logical_cpuids] = apicid;
2393 return nr_logical_cpuids++;
2394}
2395
2396int generic_processor_info(int apicid, int version)
2397{
2398 int cpu, max = nr_cpu_ids;
2399 bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
2400 phys_cpu_present_map);
2401
2402 /*
2403 * boot_cpu_physical_apicid is designed to have the apicid
2404 * returned by read_apic_id(), i.e, the apicid of the
2405 * currently booting-up processor. However, on some platforms,
2406 * it is temporarily modified by the apicid reported as BSP
2407 * through MP table. Concretely:
2408 *
2409 * - arch/x86/kernel/mpparse.c: MP_processor_info()
2410 * - arch/x86/mm/amdtopology.c: amd_numa_init()
2411 *
2412 * This function is executed with the modified
2413 * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel
2414 * parameter doesn't work to disable APs on kdump 2nd kernel.
2415 *
2416 * Since fixing handling of boot_cpu_physical_apicid requires
2417 * another discussion and tests on each platform, we leave it
2418 * for now and here we use read_apic_id() directly in this
2419 * function, generic_processor_info().
2420 */
2421 if (disabled_cpu_apicid != BAD_APICID &&
2422 disabled_cpu_apicid != read_apic_id() &&
2423 disabled_cpu_apicid == apicid) {
2424 int thiscpu = num_processors + disabled_cpus;
2425
2426 pr_warn("APIC: Disabling requested cpu."
2427 " Processor %d/0x%x ignored.\n", thiscpu, apicid);
2428
2429 disabled_cpus++;
2430 return -ENODEV;
2431 }
2432
2433 /*
2434 * If boot cpu has not been detected yet, then only allow upto
2435 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu
2436 */
2437 if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
2438 apicid != boot_cpu_physical_apicid) {
2439 int thiscpu = max + disabled_cpus - 1;
2440
2441 pr_warn("APIC: NR_CPUS/possible_cpus limit of %i almost"
2442 " reached. Keeping one slot for boot cpu."
2443 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2444
2445 disabled_cpus++;
2446 return -ENODEV;
2447 }
2448
2449 if (num_processors >= nr_cpu_ids) {
2450 int thiscpu = max + disabled_cpus;
2451
2452 pr_warn("APIC: NR_CPUS/possible_cpus limit of %i reached. "
2453 "Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2454
2455 disabled_cpus++;
2456 return -EINVAL;
2457 }
2458
2459 if (apicid == boot_cpu_physical_apicid) {
2460 /*
2461 * x86_bios_cpu_apicid is required to have processors listed
2462 * in same order as logical cpu numbers. Hence the first
2463 * entry is BSP, and so on.
2464 * boot_cpu_init() already hold bit 0 in cpu_present_mask
2465 * for BSP.
2466 */
2467 cpu = 0;
2468
2469 /* Logical cpuid 0 is reserved for BSP. */
2470 cpuid_to_apicid[0] = apicid;
2471 } else {
2472 cpu = allocate_logical_cpuid(apicid);
2473 if (cpu < 0) {
2474 disabled_cpus++;
2475 return -EINVAL;
2476 }
2477 }
2478
2479 /*
2480 * Validate version
2481 */
2482 if (version == 0x0) {
2483 pr_warn("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
2484 cpu, apicid);
2485 version = 0x10;
2486 }
2487
2488 if (version != boot_cpu_apic_version) {
2489 pr_warn("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
2490 boot_cpu_apic_version, cpu, version);
2491 }
2492
2493 if (apicid > max_physical_apicid)
2494 max_physical_apicid = apicid;
2495
2496#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2497 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2498 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
2499#endif
2500#ifdef CONFIG_X86_32
2501 early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
2502 apic->x86_32_early_logical_apicid(cpu);
2503#endif
2504 set_cpu_possible(cpu, true);
2505 physid_set(apicid, phys_cpu_present_map);
2506 set_cpu_present(cpu, true);
2507 num_processors++;
2508
2509 return cpu;
2510}
2511
2512int hard_smp_processor_id(void)
2513{
2514 return read_apic_id();
2515}
2516
2517void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg,
2518 bool dmar)
2519{
2520 memset(msg, 0, sizeof(*msg));
2521
2522 msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW;
2523 msg->arch_addr_lo.dest_mode_logical = apic->dest_mode_logical;
2524 msg->arch_addr_lo.destid_0_7 = cfg->dest_apicid & 0xFF;
2525
2526 msg->arch_data.delivery_mode = APIC_DELIVERY_MODE_FIXED;
2527 msg->arch_data.vector = cfg->vector;
2528
2529 msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH;
2530 /*
2531 * Only the IOMMU itself can use the trick of putting destination
2532 * APIC ID into the high bits of the address. Anything else would
2533 * just be writing to memory if it tried that, and needs IR to
2534 * address APICs which can't be addressed in the normal 32-bit
2535 * address range at 0xFFExxxxx. That is typically just 8 bits, but
2536 * some hypervisors allow the extended destination ID field in bits
2537 * 5-11 to be used, giving support for 15 bits of APIC IDs in total.
2538 */
2539 if (dmar)
2540 msg->arch_addr_hi.destid_8_31 = cfg->dest_apicid >> 8;
2541 else if (virt_ext_dest_id && cfg->dest_apicid < 0x8000)
2542 msg->arch_addr_lo.virt_destid_8_14 = cfg->dest_apicid >> 8;
2543 else
2544 WARN_ON_ONCE(cfg->dest_apicid > 0xFF);
2545}
2546
2547u32 x86_msi_msg_get_destid(struct msi_msg *msg, bool extid)
2548{
2549 u32 dest = msg->arch_addr_lo.destid_0_7;
2550
2551 if (extid)
2552 dest |= msg->arch_addr_hi.destid_8_31 << 8;
2553 return dest;
2554}
2555EXPORT_SYMBOL_GPL(x86_msi_msg_get_destid);
2556
2557/*
2558 * Override the generic EOI implementation with an optimized version.
2559 * Only called during early boot when only one CPU is active and with
2560 * interrupts disabled, so we know this does not race with actual APIC driver
2561 * use.
2562 */
2563void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
2564{
2565 struct apic **drv;
2566
2567 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
2568 /* Should happen once for each apic */
2569 WARN_ON((*drv)->eoi_write == eoi_write);
2570 (*drv)->native_eoi_write = (*drv)->eoi_write;
2571 (*drv)->eoi_write = eoi_write;
2572 }
2573}
2574
2575static void __init apic_bsp_up_setup(void)
2576{
2577#ifdef CONFIG_X86_64
2578 apic_write(APIC_ID, apic->set_apic_id(boot_cpu_physical_apicid));
2579#else
2580 /*
2581 * Hack: In case of kdump, after a crash, kernel might be booting
2582 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
2583 * might be zero if read from MP tables. Get it from LAPIC.
2584 */
2585# ifdef CONFIG_CRASH_DUMP
2586 boot_cpu_physical_apicid = read_apic_id();
2587# endif
2588#endif
2589 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
2590}
2591
2592/**
2593 * apic_bsp_setup - Setup function for local apic and io-apic
2594 * @upmode: Force UP mode (for APIC_init_uniprocessor)
2595 */
2596static void __init apic_bsp_setup(bool upmode)
2597{
2598 connect_bsp_APIC();
2599 if (upmode)
2600 apic_bsp_up_setup();
2601 setup_local_APIC();
2602
2603 enable_IO_APIC();
2604 end_local_APIC_setup();
2605 irq_remap_enable_fault_handling();
2606 setup_IO_APIC();
2607 lapic_update_legacy_vectors();
2608}
2609
2610#ifdef CONFIG_UP_LATE_INIT
2611void __init up_late_init(void)
2612{
2613 if (apic_intr_mode == APIC_PIC)
2614 return;
2615
2616 /* Setup local timer */
2617 x86_init.timers.setup_percpu_clockev();
2618}
2619#endif
2620
2621/*
2622 * Power management
2623 */
2624#ifdef CONFIG_PM
2625
2626static struct {
2627 /*
2628 * 'active' is true if the local APIC was enabled by us and
2629 * not the BIOS; this signifies that we are also responsible
2630 * for disabling it before entering apm/acpi suspend
2631 */
2632 int active;
2633 /* r/w apic fields */
2634 unsigned int apic_id;
2635 unsigned int apic_taskpri;
2636 unsigned int apic_ldr;
2637 unsigned int apic_dfr;
2638 unsigned int apic_spiv;
2639 unsigned int apic_lvtt;
2640 unsigned int apic_lvtpc;
2641 unsigned int apic_lvt0;
2642 unsigned int apic_lvt1;
2643 unsigned int apic_lvterr;
2644 unsigned int apic_tmict;
2645 unsigned int apic_tdcr;
2646 unsigned int apic_thmr;
2647 unsigned int apic_cmci;
2648} apic_pm_state;
2649
2650static int lapic_suspend(void)
2651{
2652 unsigned long flags;
2653 int maxlvt;
2654
2655 if (!apic_pm_state.active)
2656 return 0;
2657
2658 maxlvt = lapic_get_maxlvt();
2659
2660 apic_pm_state.apic_id = apic_read(APIC_ID);
2661 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2662 apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2663 apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2664 apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2665 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2666 if (maxlvt >= 4)
2667 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2668 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2669 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2670 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2671 apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2672 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2673#ifdef CONFIG_X86_THERMAL_VECTOR
2674 if (maxlvt >= 5)
2675 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2676#endif
2677#ifdef CONFIG_X86_MCE_INTEL
2678 if (maxlvt >= 6)
2679 apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2680#endif
2681
2682 local_irq_save(flags);
2683
2684 /*
2685 * Mask IOAPIC before disabling the local APIC to prevent stale IRR
2686 * entries on some implementations.
2687 */
2688 mask_ioapic_entries();
2689
2690 disable_local_APIC();
2691
2692 irq_remapping_disable();
2693
2694 local_irq_restore(flags);
2695 return 0;
2696}
2697
2698static void lapic_resume(void)
2699{
2700 unsigned int l, h;
2701 unsigned long flags;
2702 int maxlvt;
2703
2704 if (!apic_pm_state.active)
2705 return;
2706
2707 local_irq_save(flags);
2708
2709 /*
2710 * IO-APIC and PIC have their own resume routines.
2711 * We just mask them here to make sure the interrupt
2712 * subsystem is completely quiet while we enable x2apic
2713 * and interrupt-remapping.
2714 */
2715 mask_ioapic_entries();
2716 legacy_pic->mask_all();
2717
2718 if (x2apic_mode) {
2719 __x2apic_enable();
2720 } else {
2721 /*
2722 * Make sure the APICBASE points to the right address
2723 *
2724 * FIXME! This will be wrong if we ever support suspend on
2725 * SMP! We'll need to do this as part of the CPU restore!
2726 */
2727 if (boot_cpu_data.x86 >= 6) {
2728 rdmsr(MSR_IA32_APICBASE, l, h);
2729 l &= ~MSR_IA32_APICBASE_BASE;
2730 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2731 wrmsr(MSR_IA32_APICBASE, l, h);
2732 }
2733 }
2734
2735 maxlvt = lapic_get_maxlvt();
2736 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2737 apic_write(APIC_ID, apic_pm_state.apic_id);
2738 apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2739 apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2740 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2741 apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2742 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2743 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2744#ifdef CONFIG_X86_THERMAL_VECTOR
2745 if (maxlvt >= 5)
2746 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2747#endif
2748#ifdef CONFIG_X86_MCE_INTEL
2749 if (maxlvt >= 6)
2750 apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2751#endif
2752 if (maxlvt >= 4)
2753 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2754 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2755 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2756 apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2757 apic_write(APIC_ESR, 0);
2758 apic_read(APIC_ESR);
2759 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2760 apic_write(APIC_ESR, 0);
2761 apic_read(APIC_ESR);
2762
2763 irq_remapping_reenable(x2apic_mode);
2764
2765 local_irq_restore(flags);
2766}
2767
2768/*
2769 * This device has no shutdown method - fully functioning local APICs
2770 * are needed on every CPU up until machine_halt/restart/poweroff.
2771 */
2772
2773static struct syscore_ops lapic_syscore_ops = {
2774 .resume = lapic_resume,
2775 .suspend = lapic_suspend,
2776};
2777
2778static void apic_pm_activate(void)
2779{
2780 apic_pm_state.active = 1;
2781}
2782
2783static int __init init_lapic_sysfs(void)
2784{
2785 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2786 if (boot_cpu_has(X86_FEATURE_APIC))
2787 register_syscore_ops(&lapic_syscore_ops);
2788
2789 return 0;
2790}
2791
2792/* local apic needs to resume before other devices access its registers. */
2793core_initcall(init_lapic_sysfs);
2794
2795#else /* CONFIG_PM */
2796
2797static void apic_pm_activate(void) { }
2798
2799#endif /* CONFIG_PM */
2800
2801#ifdef CONFIG_X86_64
2802
2803static int multi_checked;
2804static int multi;
2805
2806static int set_multi(const struct dmi_system_id *d)
2807{
2808 if (multi)
2809 return 0;
2810 pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2811 multi = 1;
2812 return 0;
2813}
2814
2815static const struct dmi_system_id multi_dmi_table[] = {
2816 {
2817 .callback = set_multi,
2818 .ident = "IBM System Summit2",
2819 .matches = {
2820 DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2821 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2822 },
2823 },
2824 {}
2825};
2826
2827static void dmi_check_multi(void)
2828{
2829 if (multi_checked)
2830 return;
2831
2832 dmi_check_system(multi_dmi_table);
2833 multi_checked = 1;
2834}
2835
2836/*
2837 * apic_is_clustered_box() -- Check if we can expect good TSC
2838 *
2839 * Thus far, the major user of this is IBM's Summit2 series:
2840 * Clustered boxes may have unsynced TSC problems if they are
2841 * multi-chassis.
2842 * Use DMI to check them
2843 */
2844int apic_is_clustered_box(void)
2845{
2846 dmi_check_multi();
2847 return multi;
2848}
2849#endif
2850
2851/*
2852 * APIC command line parameters
2853 */
2854static int __init setup_disableapic(char *arg)
2855{
2856 disable_apic = 1;
2857 setup_clear_cpu_cap(X86_FEATURE_APIC);
2858 return 0;
2859}
2860early_param("disableapic", setup_disableapic);
2861
2862/* same as disableapic, for compatibility */
2863static int __init setup_nolapic(char *arg)
2864{
2865 return setup_disableapic(arg);
2866}
2867early_param("nolapic", setup_nolapic);
2868
2869static int __init parse_lapic_timer_c2_ok(char *arg)
2870{
2871 local_apic_timer_c2_ok = 1;
2872 return 0;
2873}
2874early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2875
2876static int __init parse_disable_apic_timer(char *arg)
2877{
2878 disable_apic_timer = 1;
2879 return 0;
2880}
2881early_param("noapictimer", parse_disable_apic_timer);
2882
2883static int __init parse_nolapic_timer(char *arg)
2884{
2885 disable_apic_timer = 1;
2886 return 0;
2887}
2888early_param("nolapic_timer", parse_nolapic_timer);
2889
2890static int __init apic_set_verbosity(char *arg)
2891{
2892 if (!arg) {
2893#ifdef CONFIG_X86_64
2894 skip_ioapic_setup = 0;
2895 return 0;
2896#endif
2897 return -EINVAL;
2898 }
2899
2900 if (strcmp("debug", arg) == 0)
2901 apic_verbosity = APIC_DEBUG;
2902 else if (strcmp("verbose", arg) == 0)
2903 apic_verbosity = APIC_VERBOSE;
2904#ifdef CONFIG_X86_64
2905 else {
2906 pr_warn("APIC Verbosity level %s not recognised"
2907 " use apic=verbose or apic=debug\n", arg);
2908 return -EINVAL;
2909 }
2910#endif
2911
2912 return 0;
2913}
2914early_param("apic", apic_set_verbosity);
2915
2916static int __init lapic_insert_resource(void)
2917{
2918 if (!apic_phys)
2919 return -1;
2920
2921 /* Put local APIC into the resource map. */
2922 lapic_resource.start = apic_phys;
2923 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2924 insert_resource(&iomem_resource, &lapic_resource);
2925
2926 return 0;
2927}
2928
2929/*
2930 * need call insert after e820__reserve_resources()
2931 * that is using request_resource
2932 */
2933late_initcall(lapic_insert_resource);
2934
2935static int __init apic_set_disabled_cpu_apicid(char *arg)
2936{
2937 if (!arg || !get_option(&arg, &disabled_cpu_apicid))
2938 return -EINVAL;
2939
2940 return 0;
2941}
2942early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
2943
2944static int __init apic_set_extnmi(char *arg)
2945{
2946 if (!arg)
2947 return -EINVAL;
2948
2949 if (!strncmp("all", arg, 3))
2950 apic_extnmi = APIC_EXTNMI_ALL;
2951 else if (!strncmp("none", arg, 4))
2952 apic_extnmi = APIC_EXTNMI_NONE;
2953 else if (!strncmp("bsp", arg, 3))
2954 apic_extnmi = APIC_EXTNMI_BSP;
2955 else {
2956 pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2957 return -EINVAL;
2958 }
2959
2960 return 0;
2961}
2962early_param("apic_extnmi", apic_set_extnmi);