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v3.5.6
   1/*
   2 *	Local APIC handling, local APIC timers
   3 *
   4 *	(c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
   5 *
   6 *	Fixes
   7 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
   8 *					thanks to Eric Gilmore
   9 *					and Rolf G. Tews
  10 *					for testing these extensively.
  11 *	Maciej W. Rozycki	:	Various updates and fixes.
  12 *	Mikael Pettersson	:	Power Management for UP-APIC.
  13 *	Pavel Machek and
  14 *	Mikael Pettersson	:	PM converted to driver model.
  15 */
  16
  17#include <linux/perf_event.h>
  18#include <linux/kernel_stat.h>
  19#include <linux/mc146818rtc.h>
  20#include <linux/acpi_pmtmr.h>
  21#include <linux/clockchips.h>
  22#include <linux/interrupt.h>
  23#include <linux/bootmem.h>
  24#include <linux/ftrace.h>
  25#include <linux/ioport.h>
  26#include <linux/module.h>
  27#include <linux/syscore_ops.h>
  28#include <linux/delay.h>
  29#include <linux/timex.h>
  30#include <linux/i8253.h>
  31#include <linux/dmar.h>
  32#include <linux/init.h>
  33#include <linux/cpu.h>
  34#include <linux/dmi.h>
  35#include <linux/smp.h>
  36#include <linux/mm.h>
  37
 
  38#include <asm/irq_remapping.h>
  39#include <asm/perf_event.h>
  40#include <asm/x86_init.h>
  41#include <asm/pgalloc.h>
  42#include <linux/atomic.h>
  43#include <asm/mpspec.h>
  44#include <asm/i8259.h>
  45#include <asm/proto.h>
  46#include <asm/apic.h>
  47#include <asm/io_apic.h>
  48#include <asm/desc.h>
  49#include <asm/hpet.h>
  50#include <asm/idle.h>
  51#include <asm/mtrr.h>
  52#include <asm/time.h>
  53#include <asm/smp.h>
  54#include <asm/mce.h>
  55#include <asm/tsc.h>
  56#include <asm/hypervisor.h>
  57
  58unsigned int num_processors;
  59
  60unsigned disabled_cpus __cpuinitdata;
  61
  62/* Processor that is doing the boot up */
  63unsigned int boot_cpu_physical_apicid = -1U;
 
  64
  65/*
  66 * The highest APIC ID seen during enumeration.
  67 */
  68unsigned int max_physical_apicid;
  69
  70/*
  71 * Bitmask of physically existing CPUs:
  72 */
  73physid_mask_t phys_cpu_present_map;
  74
  75/*
 
 
 
 
 
 
 
 
 
 
 
 
 
  76 * Map cpu index to physical APIC ID
  77 */
  78DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
  79DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
  80EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
  81EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
  82
  83#ifdef CONFIG_X86_32
  84
  85/*
  86 * On x86_32, the mapping between cpu and logical apicid may vary
  87 * depending on apic in use.  The following early percpu variable is
  88 * used for the mapping.  This is where the behaviors of x86_64 and 32
  89 * actually diverge.  Let's keep it ugly for now.
  90 */
  91DEFINE_EARLY_PER_CPU(int, x86_cpu_to_logical_apicid, BAD_APICID);
  92
  93/*
  94 * Knob to control our willingness to enable the local APIC.
  95 *
  96 * +1=force-enable
  97 */
  98static int force_enable_local_apic __initdata;
  99/*
 100 * APIC command line parameters
 101 */
 102static int __init parse_lapic(char *arg)
 103{
 104	force_enable_local_apic = 1;
 105	return 0;
 106}
 107early_param("lapic", parse_lapic);
 108/* Local APIC was disabled by the BIOS and enabled by the kernel */
 109static int enabled_via_apicbase;
 110
 111/*
 112 * Handle interrupt mode configuration register (IMCR).
 113 * This register controls whether the interrupt signals
 114 * that reach the BSP come from the master PIC or from the
 115 * local APIC. Before entering Symmetric I/O Mode, either
 116 * the BIOS or the operating system must switch out of
 117 * PIC Mode by changing the IMCR.
 118 */
 119static inline void imcr_pic_to_apic(void)
 120{
 121	/* select IMCR register */
 122	outb(0x70, 0x22);
 123	/* NMI and 8259 INTR go through APIC */
 124	outb(0x01, 0x23);
 125}
 126
 127static inline void imcr_apic_to_pic(void)
 128{
 129	/* select IMCR register */
 130	outb(0x70, 0x22);
 131	/* NMI and 8259 INTR go directly to BSP */
 132	outb(0x00, 0x23);
 133}
 134#endif
 135
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 136#ifdef CONFIG_X86_64
 137static int apic_calibrate_pmtmr __initdata;
 138static __init int setup_apicpmtimer(char *s)
 139{
 140	apic_calibrate_pmtmr = 1;
 141	notsc_setup(NULL);
 142	return 0;
 143}
 144__setup("apicpmtimer", setup_apicpmtimer);
 145#endif
 146
 147int x2apic_mode;
 148#ifdef CONFIG_X86_X2APIC
 149/* x2apic enabled before OS handover */
 150int x2apic_preenabled;
 151static int x2apic_disabled;
 152static int nox2apic;
 153static __init int setup_nox2apic(char *str)
 154{
 155	if (x2apic_enabled()) {
 156		int apicid = native_apic_msr_read(APIC_ID);
 157
 158		if (apicid >= 255) {
 159			pr_warning("Apicid: %08x, cannot enforce nox2apic\n",
 160				   apicid);
 161			return 0;
 162		}
 163
 164		pr_warning("x2apic already enabled. will disable it\n");
 165	} else
 166		setup_clear_cpu_cap(X86_FEATURE_X2APIC);
 167
 168	nox2apic = 1;
 169
 170	return 0;
 171}
 172early_param("nox2apic", setup_nox2apic);
 173#endif
 174
 175unsigned long mp_lapic_addr;
 176int disable_apic;
 177/* Disable local APIC timer from the kernel commandline or via dmi quirk */
 178static int disable_apic_timer __initdata;
 179/* Local APIC timer works in C2 */
 180int local_apic_timer_c2_ok;
 181EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
 182
 183int first_system_vector = 0xfe;
 184
 185/*
 186 * Debug level, exported for io_apic.c
 187 */
 188unsigned int apic_verbosity;
 189
 190int pic_mode;
 191
 192/* Have we found an MP table */
 193int smp_found_config;
 194
 195static struct resource lapic_resource = {
 196	.name = "Local APIC",
 197	.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
 198};
 199
 200unsigned int lapic_timer_frequency = 0;
 201
 202static void apic_pm_activate(void);
 203
 204static unsigned long apic_phys;
 205
 206/*
 207 * Get the LAPIC version
 208 */
 209static inline int lapic_get_version(void)
 210{
 211	return GET_APIC_VERSION(apic_read(APIC_LVR));
 212}
 213
 214/*
 215 * Check, if the APIC is integrated or a separate chip
 216 */
 217static inline int lapic_is_integrated(void)
 218{
 219#ifdef CONFIG_X86_64
 220	return 1;
 221#else
 222	return APIC_INTEGRATED(lapic_get_version());
 223#endif
 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	return lapic_get_version() >= 0x14;
 236}
 237
 238/*
 239 * right after this call apic become NOOP driven
 240 * so apic->write/read doesn't do anything
 241 */
 242static void __init apic_disable(void)
 243{
 244	pr_info("APIC: switched to apic NOOP\n");
 245	apic = &apic_noop;
 246}
 247
 248void native_apic_wait_icr_idle(void)
 249{
 250	while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
 251		cpu_relax();
 252}
 253
 254u32 native_safe_apic_wait_icr_idle(void)
 255{
 256	u32 send_status;
 257	int timeout;
 258
 259	timeout = 0;
 260	do {
 261		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
 262		if (!send_status)
 263			break;
 264		inc_irq_stat(icr_read_retry_count);
 265		udelay(100);
 266	} while (timeout++ < 1000);
 267
 268	return send_status;
 269}
 270
 271void native_apic_icr_write(u32 low, u32 id)
 272{
 
 
 
 273	apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
 274	apic_write(APIC_ICR, low);
 
 275}
 276
 277u64 native_apic_icr_read(void)
 278{
 279	u32 icr1, icr2;
 280
 281	icr2 = apic_read(APIC_ICR2);
 282	icr1 = apic_read(APIC_ICR);
 283
 284	return icr1 | ((u64)icr2 << 32);
 285}
 286
 287#ifdef CONFIG_X86_32
 288/**
 289 * get_physical_broadcast - Get number of physical broadcast IDs
 290 */
 291int get_physical_broadcast(void)
 292{
 293	return modern_apic() ? 0xff : 0xf;
 294}
 295#endif
 296
 297/**
 298 * lapic_get_maxlvt - get the maximum number of local vector table entries
 299 */
 300int lapic_get_maxlvt(void)
 301{
 302	unsigned int v;
 303
 304	v = apic_read(APIC_LVR);
 305	/*
 306	 * - we always have APIC integrated on 64bit mode
 307	 * - 82489DXs do not report # of LVT entries
 308	 */
 309	return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
 310}
 311
 312/*
 313 * Local APIC timer
 314 */
 315
 316/* Clock divisor */
 317#define APIC_DIVISOR 16
 
 318
 319/*
 320 * This function sets up the local APIC timer, with a timeout of
 321 * 'clocks' APIC bus clock. During calibration we actually call
 322 * this function twice on the boot CPU, once with a bogus timeout
 323 * value, second time for real. The other (noncalibrating) CPUs
 324 * call this function only once, with the real, calibrated value.
 325 *
 326 * We do reads before writes even if unnecessary, to get around the
 327 * P5 APIC double write bug.
 328 */
 329static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
 330{
 331	unsigned int lvtt_value, tmp_value;
 332
 333	lvtt_value = LOCAL_TIMER_VECTOR;
 334	if (!oneshot)
 335		lvtt_value |= APIC_LVT_TIMER_PERIODIC;
 
 
 
 336	if (!lapic_is_integrated())
 337		lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
 338
 339	if (!irqen)
 340		lvtt_value |= APIC_LVT_MASKED;
 341
 342	apic_write(APIC_LVTT, lvtt_value);
 343
 
 
 
 
 
 
 
 
 
 
 
 
 344	/*
 345	 * Divide PICLK by 16
 346	 */
 347	tmp_value = apic_read(APIC_TDCR);
 348	apic_write(APIC_TDCR,
 349		(tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
 350		APIC_TDR_DIV_16);
 351
 352	if (!oneshot)
 353		apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
 354}
 355
 356/*
 357 * Setup extended LVT, AMD specific
 358 *
 359 * Software should use the LVT offsets the BIOS provides.  The offsets
 360 * are determined by the subsystems using it like those for MCE
 361 * threshold or IBS.  On K8 only offset 0 (APIC500) and MCE interrupts
 362 * are supported. Beginning with family 10h at least 4 offsets are
 363 * available.
 364 *
 365 * Since the offsets must be consistent for all cores, we keep track
 366 * of the LVT offsets in software and reserve the offset for the same
 367 * vector also to be used on other cores. An offset is freed by
 368 * setting the entry to APIC_EILVT_MASKED.
 369 *
 370 * If the BIOS is right, there should be no conflicts. Otherwise a
 371 * "[Firmware Bug]: ..." error message is generated. However, if
 372 * software does not properly determines the offsets, it is not
 373 * necessarily a BIOS bug.
 374 */
 375
 376static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
 377
 378static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
 379{
 380	return (old & APIC_EILVT_MASKED)
 381		|| (new == APIC_EILVT_MASKED)
 382		|| ((new & ~APIC_EILVT_MASKED) == old);
 383}
 384
 385static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
 386{
 387	unsigned int rsvd, vector;
 388
 389	if (offset >= APIC_EILVT_NR_MAX)
 390		return ~0;
 391
 392	rsvd = atomic_read(&eilvt_offsets[offset]);
 393	do {
 394		vector = rsvd & ~APIC_EILVT_MASKED;	/* 0: unassigned */
 395		if (vector && !eilvt_entry_is_changeable(vector, new))
 396			/* may not change if vectors are different */
 397			return rsvd;
 398		rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
 399	} while (rsvd != new);
 400
 401	rsvd &= ~APIC_EILVT_MASKED;
 402	if (rsvd && rsvd != vector)
 403		pr_info("LVT offset %d assigned for vector 0x%02x\n",
 404			offset, rsvd);
 405
 406	return new;
 407}
 408
 409/*
 410 * If mask=1, the LVT entry does not generate interrupts while mask=0
 411 * enables the vector. See also the BKDGs. Must be called with
 412 * preemption disabled.
 413 */
 414
 415int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
 416{
 417	unsigned long reg = APIC_EILVTn(offset);
 418	unsigned int new, old, reserved;
 419
 420	new = (mask << 16) | (msg_type << 8) | vector;
 421	old = apic_read(reg);
 422	reserved = reserve_eilvt_offset(offset, new);
 423
 424	if (reserved != new) {
 425		pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
 426		       "vector 0x%x, but the register is already in use for "
 427		       "vector 0x%x on another cpu\n",
 428		       smp_processor_id(), reg, offset, new, reserved);
 429		return -EINVAL;
 430	}
 431
 432	if (!eilvt_entry_is_changeable(old, new)) {
 433		pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
 434		       "vector 0x%x, but the register is already in use for "
 435		       "vector 0x%x on this cpu\n",
 436		       smp_processor_id(), reg, offset, new, old);
 437		return -EBUSY;
 438	}
 439
 440	apic_write(reg, new);
 441
 442	return 0;
 443}
 444EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
 445
 446/*
 447 * Program the next event, relative to now
 448 */
 449static int lapic_next_event(unsigned long delta,
 450			    struct clock_event_device *evt)
 451{
 452	apic_write(APIC_TMICT, delta);
 453	return 0;
 454}
 455
 456/*
 457 * Setup the lapic timer in periodic or oneshot mode
 458 */
 459static void lapic_timer_setup(enum clock_event_mode mode,
 460			      struct clock_event_device *evt)
 
 
 
 
 
 
 461{
 462	unsigned long flags;
 463	unsigned int v;
 464
 465	/* Lapic used as dummy for broadcast ? */
 466	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
 467		return;
 468
 469	local_irq_save(flags);
 
 
 
 
 
 470
 471	switch (mode) {
 472	case CLOCK_EVT_MODE_PERIODIC:
 473	case CLOCK_EVT_MODE_ONESHOT:
 474		__setup_APIC_LVTT(lapic_timer_frequency,
 475				  mode != CLOCK_EVT_MODE_PERIODIC, 1);
 476		break;
 477	case CLOCK_EVT_MODE_UNUSED:
 478	case CLOCK_EVT_MODE_SHUTDOWN:
 479		v = apic_read(APIC_LVTT);
 480		v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
 481		apic_write(APIC_LVTT, v);
 482		apic_write(APIC_TMICT, 0);
 483		break;
 484	case CLOCK_EVT_MODE_RESUME:
 485		/* Nothing to do here */
 486		break;
 487	}
 488
 489	local_irq_restore(flags);
 
 
 
 
 
 
 
 
 
 
 
 490}
 491
 492/*
 493 * Local APIC timer broadcast function
 494 */
 495static void lapic_timer_broadcast(const struct cpumask *mask)
 496{
 497#ifdef CONFIG_SMP
 498	apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
 499#endif
 500}
 501
 502
 503/*
 504 * The local apic timer can be used for any function which is CPU local.
 505 */
 506static struct clock_event_device lapic_clockevent = {
 507	.name		= "lapic",
 508	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
 509			| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
 510	.shift		= 32,
 511	.set_mode	= lapic_timer_setup,
 512	.set_next_event	= lapic_next_event,
 513	.broadcast	= lapic_timer_broadcast,
 514	.rating		= 100,
 515	.irq		= -1,
 
 
 
 516};
 517static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
 518
 519/*
 520 * Setup the local APIC timer for this CPU. Copy the initialized values
 521 * of the boot CPU and register the clock event in the framework.
 522 */
 523static void __cpuinit setup_APIC_timer(void)
 524{
 525	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
 526
 527	if (this_cpu_has(X86_FEATURE_ARAT)) {
 528		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
 529		/* Make LAPIC timer preferrable over percpu HPET */
 530		lapic_clockevent.rating = 150;
 531	}
 532
 533	memcpy(levt, &lapic_clockevent, sizeof(*levt));
 534	levt->cpumask = cpumask_of(smp_processor_id());
 535
 536	clockevents_register_device(levt);
 
 
 
 
 
 
 
 
 537}
 538
 539/*
 540 * In this functions we calibrate APIC bus clocks to the external timer.
 541 *
 542 * We want to do the calibration only once since we want to have local timer
 543 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
 544 * frequency.
 545 *
 546 * This was previously done by reading the PIT/HPET and waiting for a wrap
 547 * around to find out, that a tick has elapsed. I have a box, where the PIT
 548 * readout is broken, so it never gets out of the wait loop again. This was
 549 * also reported by others.
 550 *
 551 * Monitoring the jiffies value is inaccurate and the clockevents
 552 * infrastructure allows us to do a simple substitution of the interrupt
 553 * handler.
 554 *
 555 * The calibration routine also uses the pm_timer when possible, as the PIT
 556 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
 557 * back to normal later in the boot process).
 558 */
 559
 560#define LAPIC_CAL_LOOPS		(HZ/10)
 561
 562static __initdata int lapic_cal_loops = -1;
 563static __initdata long lapic_cal_t1, lapic_cal_t2;
 564static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
 565static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
 566static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
 567
 568/*
 569 * Temporary interrupt handler.
 570 */
 571static void __init lapic_cal_handler(struct clock_event_device *dev)
 572{
 573	unsigned long long tsc = 0;
 574	long tapic = apic_read(APIC_TMCCT);
 575	unsigned long pm = acpi_pm_read_early();
 576
 577	if (cpu_has_tsc)
 578		rdtscll(tsc);
 579
 580	switch (lapic_cal_loops++) {
 581	case 0:
 582		lapic_cal_t1 = tapic;
 583		lapic_cal_tsc1 = tsc;
 584		lapic_cal_pm1 = pm;
 585		lapic_cal_j1 = jiffies;
 586		break;
 587
 588	case LAPIC_CAL_LOOPS:
 589		lapic_cal_t2 = tapic;
 590		lapic_cal_tsc2 = tsc;
 591		if (pm < lapic_cal_pm1)
 592			pm += ACPI_PM_OVRRUN;
 593		lapic_cal_pm2 = pm;
 594		lapic_cal_j2 = jiffies;
 595		break;
 596	}
 597}
 598
 599static int __init
 600calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
 601{
 602	const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
 603	const long pm_thresh = pm_100ms / 100;
 604	unsigned long mult;
 605	u64 res;
 606
 607#ifndef CONFIG_X86_PM_TIMER
 608	return -1;
 609#endif
 610
 611	apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
 612
 613	/* Check, if the PM timer is available */
 614	if (!deltapm)
 615		return -1;
 616
 617	mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
 618
 619	if (deltapm > (pm_100ms - pm_thresh) &&
 620	    deltapm < (pm_100ms + pm_thresh)) {
 621		apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
 622		return 0;
 623	}
 624
 625	res = (((u64)deltapm) *  mult) >> 22;
 626	do_div(res, 1000000);
 627	pr_warning("APIC calibration not consistent "
 628		   "with PM-Timer: %ldms instead of 100ms\n",(long)res);
 629
 630	/* Correct the lapic counter value */
 631	res = (((u64)(*delta)) * pm_100ms);
 632	do_div(res, deltapm);
 633	pr_info("APIC delta adjusted to PM-Timer: "
 634		"%lu (%ld)\n", (unsigned long)res, *delta);
 635	*delta = (long)res;
 636
 637	/* Correct the tsc counter value */
 638	if (cpu_has_tsc) {
 639		res = (((u64)(*deltatsc)) * pm_100ms);
 640		do_div(res, deltapm);
 641		apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
 642					  "PM-Timer: %lu (%ld)\n",
 643					(unsigned long)res, *deltatsc);
 644		*deltatsc = (long)res;
 645	}
 646
 647	return 0;
 648}
 649
 650static int __init calibrate_APIC_clock(void)
 651{
 652	struct clock_event_device *levt = &__get_cpu_var(lapic_events);
 653	void (*real_handler)(struct clock_event_device *dev);
 654	unsigned long deltaj;
 655	long delta, deltatsc;
 656	int pm_referenced = 0;
 657
 658	/**
 659	 * check if lapic timer has already been calibrated by platform
 660	 * specific routine, such as tsc calibration code. if so, we just fill
 661	 * in the clockevent structure and return.
 662	 */
 663
 664	if (lapic_timer_frequency) {
 
 
 665		apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
 666				lapic_timer_frequency);
 667		lapic_clockevent.mult = div_sc(lapic_timer_frequency/APIC_DIVISOR,
 668					TICK_NSEC, lapic_clockevent.shift);
 669		lapic_clockevent.max_delta_ns =
 670			clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
 671		lapic_clockevent.min_delta_ns =
 672			clockevent_delta2ns(0xF, &lapic_clockevent);
 673		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
 674		return 0;
 675	}
 676
 
 
 
 677	local_irq_disable();
 678
 679	/* Replace the global interrupt handler */
 680	real_handler = global_clock_event->event_handler;
 681	global_clock_event->event_handler = lapic_cal_handler;
 682
 683	/*
 684	 * Setup the APIC counter to maximum. There is no way the lapic
 685	 * can underflow in the 100ms detection time frame
 686	 */
 687	__setup_APIC_LVTT(0xffffffff, 0, 0);
 688
 689	/* Let the interrupts run */
 690	local_irq_enable();
 691
 692	while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
 693		cpu_relax();
 694
 695	local_irq_disable();
 696
 697	/* Restore the real event handler */
 698	global_clock_event->event_handler = real_handler;
 699
 700	/* Build delta t1-t2 as apic timer counts down */
 701	delta = lapic_cal_t1 - lapic_cal_t2;
 702	apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
 703
 704	deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
 705
 706	/* we trust the PM based calibration if possible */
 707	pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
 708					&delta, &deltatsc);
 709
 710	/* Calculate the scaled math multiplication factor */
 711	lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
 712				       lapic_clockevent.shift);
 713	lapic_clockevent.max_delta_ns =
 714		clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
 715	lapic_clockevent.min_delta_ns =
 716		clockevent_delta2ns(0xF, &lapic_clockevent);
 717
 718	lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
 719
 720	apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
 721	apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
 722	apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
 723		    lapic_timer_frequency);
 724
 725	if (cpu_has_tsc) {
 726		apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
 727			    "%ld.%04ld MHz.\n",
 728			    (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
 729			    (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
 730	}
 731
 732	apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
 733		    "%u.%04u MHz.\n",
 734		    lapic_timer_frequency / (1000000 / HZ),
 735		    lapic_timer_frequency % (1000000 / HZ));
 736
 737	/*
 738	 * Do a sanity check on the APIC calibration result
 739	 */
 740	if (lapic_timer_frequency < (1000000 / HZ)) {
 741		local_irq_enable();
 742		pr_warning("APIC frequency too slow, disabling apic timer\n");
 743		return -1;
 744	}
 745
 746	levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
 747
 748	/*
 749	 * PM timer calibration failed or not turned on
 750	 * so lets try APIC timer based calibration
 751	 */
 752	if (!pm_referenced) {
 753		apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
 754
 755		/*
 756		 * Setup the apic timer manually
 757		 */
 758		levt->event_handler = lapic_cal_handler;
 759		lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
 760		lapic_cal_loops = -1;
 761
 762		/* Let the interrupts run */
 763		local_irq_enable();
 764
 765		while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
 766			cpu_relax();
 767
 768		/* Stop the lapic timer */
 769		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
 
 770
 771		/* Jiffies delta */
 772		deltaj = lapic_cal_j2 - lapic_cal_j1;
 773		apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
 774
 775		/* Check, if the jiffies result is consistent */
 776		if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
 777			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
 778		else
 779			levt->features |= CLOCK_EVT_FEAT_DUMMY;
 780	} else
 781		local_irq_enable();
 782
 783	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
 784		pr_warning("APIC timer disabled due to verification failure\n");
 785			return -1;
 786	}
 787
 788	return 0;
 789}
 790
 791/*
 792 * Setup the boot APIC
 793 *
 794 * Calibrate and verify the result.
 795 */
 796void __init setup_boot_APIC_clock(void)
 797{
 798	/*
 799	 * The local apic timer can be disabled via the kernel
 800	 * commandline or from the CPU detection code. Register the lapic
 801	 * timer as a dummy clock event source on SMP systems, so the
 802	 * broadcast mechanism is used. On UP systems simply ignore it.
 803	 */
 804	if (disable_apic_timer) {
 805		pr_info("Disabling APIC timer\n");
 806		/* No broadcast on UP ! */
 807		if (num_possible_cpus() > 1) {
 808			lapic_clockevent.mult = 1;
 809			setup_APIC_timer();
 810		}
 811		return;
 812	}
 813
 814	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
 815		    "calibrating APIC timer ...\n");
 816
 817	if (calibrate_APIC_clock()) {
 818		/* No broadcast on UP ! */
 819		if (num_possible_cpus() > 1)
 820			setup_APIC_timer();
 821		return;
 822	}
 823
 824	/*
 825	 * If nmi_watchdog is set to IO_APIC, we need the
 826	 * PIT/HPET going.  Otherwise register lapic as a dummy
 827	 * device.
 828	 */
 829	lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
 830
 831	/* Setup the lapic or request the broadcast */
 832	setup_APIC_timer();
 833}
 834
 835void __cpuinit setup_secondary_APIC_clock(void)
 836{
 837	setup_APIC_timer();
 838}
 839
 840/*
 841 * The guts of the apic timer interrupt
 842 */
 843static void local_apic_timer_interrupt(void)
 844{
 845	int cpu = smp_processor_id();
 846	struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
 847
 848	/*
 849	 * Normally we should not be here till LAPIC has been initialized but
 850	 * in some cases like kdump, its possible that there is a pending LAPIC
 851	 * timer interrupt from previous kernel's context and is delivered in
 852	 * new kernel the moment interrupts are enabled.
 853	 *
 854	 * Interrupts are enabled early and LAPIC is setup much later, hence
 855	 * its possible that when we get here evt->event_handler is NULL.
 856	 * Check for event_handler being NULL and discard the interrupt as
 857	 * spurious.
 858	 */
 859	if (!evt->event_handler) {
 860		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
 861		/* Switch it off */
 862		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
 863		return;
 864	}
 865
 866	/*
 867	 * the NMI deadlock-detector uses this.
 868	 */
 869	inc_irq_stat(apic_timer_irqs);
 870
 871	evt->event_handler(evt);
 872}
 873
 874/*
 875 * Local APIC timer interrupt. This is the most natural way for doing
 876 * local interrupts, but local timer interrupts can be emulated by
 877 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
 878 *
 879 * [ if a single-CPU system runs an SMP kernel then we call the local
 880 *   interrupt as well. Thus we cannot inline the local irq ... ]
 881 */
 882void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
 883{
 884	struct pt_regs *old_regs = set_irq_regs(regs);
 885
 886	/*
 887	 * NOTE! We'd better ACK the irq immediately,
 888	 * because timer handling can be slow.
 
 
 
 
 889	 */
 890	ack_APIC_irq();
 
 
 
 
 
 
 
 
 
 
 891	/*
 
 
 
 892	 * update_process_times() expects us to have done irq_enter().
 893	 * Besides, if we don't timer interrupts ignore the global
 894	 * interrupt lock, which is the WrongThing (tm) to do.
 895	 */
 896	irq_enter();
 897	exit_idle();
 898	local_apic_timer_interrupt();
 899	irq_exit();
 
 900
 901	set_irq_regs(old_regs);
 902}
 903
 904int setup_profiling_timer(unsigned int multiplier)
 905{
 906	return -EINVAL;
 907}
 908
 909/*
 910 * Local APIC start and shutdown
 911 */
 912
 913/**
 914 * clear_local_APIC - shutdown the local APIC
 915 *
 916 * This is called, when a CPU is disabled and before rebooting, so the state of
 917 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
 918 * leftovers during boot.
 919 */
 920void clear_local_APIC(void)
 921{
 922	int maxlvt;
 923	u32 v;
 924
 925	/* APIC hasn't been mapped yet */
 926	if (!x2apic_mode && !apic_phys)
 927		return;
 928
 929	maxlvt = lapic_get_maxlvt();
 930	/*
 931	 * Masking an LVT entry can trigger a local APIC error
 932	 * if the vector is zero. Mask LVTERR first to prevent this.
 933	 */
 934	if (maxlvt >= 3) {
 935		v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
 936		apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
 937	}
 938	/*
 939	 * Careful: we have to set masks only first to deassert
 940	 * any level-triggered sources.
 941	 */
 942	v = apic_read(APIC_LVTT);
 943	apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
 944	v = apic_read(APIC_LVT0);
 945	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
 946	v = apic_read(APIC_LVT1);
 947	apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
 948	if (maxlvt >= 4) {
 949		v = apic_read(APIC_LVTPC);
 950		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
 951	}
 952
 953	/* lets not touch this if we didn't frob it */
 954#ifdef CONFIG_X86_THERMAL_VECTOR
 955	if (maxlvt >= 5) {
 956		v = apic_read(APIC_LVTTHMR);
 957		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
 958	}
 959#endif
 960#ifdef CONFIG_X86_MCE_INTEL
 961	if (maxlvt >= 6) {
 962		v = apic_read(APIC_LVTCMCI);
 963		if (!(v & APIC_LVT_MASKED))
 964			apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
 965	}
 966#endif
 967
 968	/*
 969	 * Clean APIC state for other OSs:
 970	 */
 971	apic_write(APIC_LVTT, APIC_LVT_MASKED);
 972	apic_write(APIC_LVT0, APIC_LVT_MASKED);
 973	apic_write(APIC_LVT1, APIC_LVT_MASKED);
 974	if (maxlvt >= 3)
 975		apic_write(APIC_LVTERR, APIC_LVT_MASKED);
 976	if (maxlvt >= 4)
 977		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
 978
 979	/* Integrated APIC (!82489DX) ? */
 980	if (lapic_is_integrated()) {
 981		if (maxlvt > 3)
 982			/* Clear ESR due to Pentium errata 3AP and 11AP */
 983			apic_write(APIC_ESR, 0);
 984		apic_read(APIC_ESR);
 985	}
 986}
 987
 988/**
 989 * disable_local_APIC - clear and disable the local APIC
 990 */
 991void disable_local_APIC(void)
 992{
 993	unsigned int value;
 994
 995	/* APIC hasn't been mapped yet */
 996	if (!x2apic_mode && !apic_phys)
 997		return;
 998
 999	clear_local_APIC();
1000
1001	/*
1002	 * Disable APIC (implies clearing of registers
1003	 * for 82489DX!).
1004	 */
1005	value = apic_read(APIC_SPIV);
1006	value &= ~APIC_SPIV_APIC_ENABLED;
1007	apic_write(APIC_SPIV, value);
1008
1009#ifdef CONFIG_X86_32
1010	/*
1011	 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1012	 * restore the disabled state.
1013	 */
1014	if (enabled_via_apicbase) {
1015		unsigned int l, h;
1016
1017		rdmsr(MSR_IA32_APICBASE, l, h);
1018		l &= ~MSR_IA32_APICBASE_ENABLE;
1019		wrmsr(MSR_IA32_APICBASE, l, h);
1020	}
1021#endif
1022}
1023
1024/*
1025 * If Linux enabled the LAPIC against the BIOS default disable it down before
1026 * re-entering the BIOS on shutdown.  Otherwise the BIOS may get confused and
1027 * not power-off.  Additionally clear all LVT entries before disable_local_APIC
1028 * for the case where Linux didn't enable the LAPIC.
1029 */
1030void lapic_shutdown(void)
1031{
1032	unsigned long flags;
1033
1034	if (!cpu_has_apic && !apic_from_smp_config())
1035		return;
1036
1037	local_irq_save(flags);
1038
1039#ifdef CONFIG_X86_32
1040	if (!enabled_via_apicbase)
1041		clear_local_APIC();
1042	else
1043#endif
1044		disable_local_APIC();
1045
1046
1047	local_irq_restore(flags);
1048}
1049
1050/*
1051 * This is to verify that we're looking at a real local APIC.
1052 * Check these against your board if the CPUs aren't getting
1053 * started for no apparent reason.
1054 */
1055int __init verify_local_APIC(void)
1056{
1057	unsigned int reg0, reg1;
1058
1059	/*
1060	 * The version register is read-only in a real APIC.
1061	 */
1062	reg0 = apic_read(APIC_LVR);
1063	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
1064	apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
1065	reg1 = apic_read(APIC_LVR);
1066	apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
1067
1068	/*
1069	 * The two version reads above should print the same
1070	 * numbers.  If the second one is different, then we
1071	 * poke at a non-APIC.
1072	 */
1073	if (reg1 != reg0)
1074		return 0;
1075
1076	/*
1077	 * Check if the version looks reasonably.
1078	 */
1079	reg1 = GET_APIC_VERSION(reg0);
1080	if (reg1 == 0x00 || reg1 == 0xff)
1081		return 0;
1082	reg1 = lapic_get_maxlvt();
1083	if (reg1 < 0x02 || reg1 == 0xff)
1084		return 0;
1085
1086	/*
1087	 * The ID register is read/write in a real APIC.
1088	 */
1089	reg0 = apic_read(APIC_ID);
1090	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
1091	apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
1092	reg1 = apic_read(APIC_ID);
1093	apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
1094	apic_write(APIC_ID, reg0);
1095	if (reg1 != (reg0 ^ apic->apic_id_mask))
1096		return 0;
1097
1098	/*
1099	 * The next two are just to see if we have sane values.
1100	 * They're only really relevant if we're in Virtual Wire
1101	 * compatibility mode, but most boxes are anymore.
1102	 */
1103	reg0 = apic_read(APIC_LVT0);
1104	apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
1105	reg1 = apic_read(APIC_LVT1);
1106	apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
1107
1108	return 1;
1109}
1110
1111/**
1112 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1113 */
1114void __init sync_Arb_IDs(void)
1115{
1116	/*
1117	 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1118	 * needed on AMD.
1119	 */
1120	if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1121		return;
1122
1123	/*
1124	 * Wait for idle.
1125	 */
1126	apic_wait_icr_idle();
1127
1128	apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1129	apic_write(APIC_ICR, APIC_DEST_ALLINC |
1130			APIC_INT_LEVELTRIG | APIC_DM_INIT);
1131}
1132
1133/*
1134 * An initial setup of the virtual wire mode.
1135 */
1136void __init init_bsp_APIC(void)
1137{
1138	unsigned int value;
1139
1140	/*
1141	 * Don't do the setup now if we have a SMP BIOS as the
1142	 * through-I/O-APIC virtual wire mode might be active.
1143	 */
1144	if (smp_found_config || !cpu_has_apic)
1145		return;
1146
1147	/*
1148	 * Do not trust the local APIC being empty at bootup.
1149	 */
1150	clear_local_APIC();
1151
1152	/*
1153	 * Enable APIC.
1154	 */
1155	value = apic_read(APIC_SPIV);
1156	value &= ~APIC_VECTOR_MASK;
1157	value |= APIC_SPIV_APIC_ENABLED;
1158
1159#ifdef CONFIG_X86_32
1160	/* This bit is reserved on P4/Xeon and should be cleared */
1161	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1162	    (boot_cpu_data.x86 == 15))
1163		value &= ~APIC_SPIV_FOCUS_DISABLED;
1164	else
1165#endif
1166		value |= APIC_SPIV_FOCUS_DISABLED;
1167	value |= SPURIOUS_APIC_VECTOR;
1168	apic_write(APIC_SPIV, value);
1169
1170	/*
1171	 * Set up the virtual wire mode.
1172	 */
1173	apic_write(APIC_LVT0, APIC_DM_EXTINT);
1174	value = APIC_DM_NMI;
1175	if (!lapic_is_integrated())		/* 82489DX */
1176		value |= APIC_LVT_LEVEL_TRIGGER;
 
 
1177	apic_write(APIC_LVT1, value);
1178}
1179
1180static void __cpuinit lapic_setup_esr(void)
1181{
1182	unsigned int oldvalue, value, maxlvt;
1183
1184	if (!lapic_is_integrated()) {
1185		pr_info("No ESR for 82489DX.\n");
1186		return;
1187	}
1188
1189	if (apic->disable_esr) {
1190		/*
1191		 * Something untraceable is creating bad interrupts on
1192		 * secondary quads ... for the moment, just leave the
1193		 * ESR disabled - we can't do anything useful with the
1194		 * errors anyway - mbligh
1195		 */
1196		pr_info("Leaving ESR disabled.\n");
1197		return;
1198	}
1199
1200	maxlvt = lapic_get_maxlvt();
1201	if (maxlvt > 3)		/* Due to the Pentium erratum 3AP. */
1202		apic_write(APIC_ESR, 0);
1203	oldvalue = apic_read(APIC_ESR);
1204
1205	/* enables sending errors */
1206	value = ERROR_APIC_VECTOR;
1207	apic_write(APIC_LVTERR, value);
1208
1209	/*
1210	 * spec says clear errors after enabling vector.
1211	 */
1212	if (maxlvt > 3)
1213		apic_write(APIC_ESR, 0);
1214	value = apic_read(APIC_ESR);
1215	if (value != oldvalue)
1216		apic_printk(APIC_VERBOSE, "ESR value before enabling "
1217			"vector: 0x%08x  after: 0x%08x\n",
1218			oldvalue, value);
1219}
1220
1221/**
1222 * setup_local_APIC - setup the local APIC
1223 *
1224 * Used to setup local APIC while initializing BSP or bringin up APs.
1225 * Always called with preemption disabled.
1226 */
1227void __cpuinit setup_local_APIC(void)
1228{
1229	int cpu = smp_processor_id();
1230	unsigned int value, queued;
1231	int i, j, acked = 0;
1232	unsigned long long tsc = 0, ntsc;
1233	long long max_loops = cpu_khz;
1234
1235	if (cpu_has_tsc)
1236		rdtscll(tsc);
1237
1238	if (disable_apic) {
1239		disable_ioapic_support();
1240		return;
1241	}
1242
1243#ifdef CONFIG_X86_32
1244	/* Pound the ESR really hard over the head with a big hammer - mbligh */
1245	if (lapic_is_integrated() && apic->disable_esr) {
1246		apic_write(APIC_ESR, 0);
1247		apic_write(APIC_ESR, 0);
1248		apic_write(APIC_ESR, 0);
1249		apic_write(APIC_ESR, 0);
1250	}
1251#endif
1252	perf_events_lapic_init();
1253
1254	/*
1255	 * Double-check whether this APIC is really registered.
1256	 * This is meaningless in clustered apic mode, so we skip it.
1257	 */
1258	BUG_ON(!apic->apic_id_registered());
1259
1260	/*
1261	 * Intel recommends to set DFR, LDR and TPR before enabling
1262	 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
1263	 * document number 292116).  So here it goes...
1264	 */
1265	apic->init_apic_ldr();
1266
1267#ifdef CONFIG_X86_32
1268	/*
1269	 * APIC LDR is initialized.  If logical_apicid mapping was
1270	 * initialized during get_smp_config(), make sure it matches the
1271	 * actual value.
1272	 */
1273	i = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
1274	WARN_ON(i != BAD_APICID && i != logical_smp_processor_id());
1275	/* always use the value from LDR */
1276	early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
1277		logical_smp_processor_id();
1278
1279	/*
1280	 * Some NUMA implementations (NUMAQ) don't initialize apicid to
1281	 * node mapping during NUMA init.  Now that logical apicid is
1282	 * guaranteed to be known, give it another chance.  This is already
1283	 * a bit too late - percpu allocation has already happened without
1284	 * proper NUMA affinity.
1285	 */
1286	if (apic->x86_32_numa_cpu_node)
1287		set_apicid_to_node(early_per_cpu(x86_cpu_to_apicid, cpu),
1288				   apic->x86_32_numa_cpu_node(cpu));
1289#endif
1290
1291	/*
1292	 * Set Task Priority to 'accept all'. We never change this
1293	 * later on.
1294	 */
1295	value = apic_read(APIC_TASKPRI);
1296	value &= ~APIC_TPRI_MASK;
1297	apic_write(APIC_TASKPRI, value);
1298
1299	/*
1300	 * After a crash, we no longer service the interrupts and a pending
1301	 * interrupt from previous kernel might still have ISR bit set.
1302	 *
1303	 * Most probably by now CPU has serviced that pending interrupt and
1304	 * it might not have done the ack_APIC_irq() because it thought,
1305	 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1306	 * does not clear the ISR bit and cpu thinks it has already serivced
1307	 * the interrupt. Hence a vector might get locked. It was noticed
1308	 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1309	 */
1310	do {
1311		queued = 0;
1312		for (i = APIC_ISR_NR - 1; i >= 0; i--)
1313			queued |= apic_read(APIC_IRR + i*0x10);
1314
1315		for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1316			value = apic_read(APIC_ISR + i*0x10);
1317			for (j = 31; j >= 0; j--) {
1318				if (value & (1<<j)) {
1319					ack_APIC_irq();
1320					acked++;
1321				}
1322			}
1323		}
1324		if (acked > 256) {
1325			printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n",
1326			       acked);
1327			break;
1328		}
1329		if (queued) {
1330			if (cpu_has_tsc) {
1331				rdtscll(ntsc);
1332				max_loops = (cpu_khz << 10) - (ntsc - tsc);
1333			} else
1334				max_loops--;
1335		}
1336	} while (queued && max_loops > 0);
1337	WARN_ON(max_loops <= 0);
1338
1339	/*
1340	 * Now that we are all set up, enable the APIC
1341	 */
1342	value = apic_read(APIC_SPIV);
1343	value &= ~APIC_VECTOR_MASK;
1344	/*
1345	 * Enable APIC
1346	 */
1347	value |= APIC_SPIV_APIC_ENABLED;
1348
1349#ifdef CONFIG_X86_32
1350	/*
1351	 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1352	 * certain networking cards. If high frequency interrupts are
1353	 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1354	 * entry is masked/unmasked at a high rate as well then sooner or
1355	 * later IOAPIC line gets 'stuck', no more interrupts are received
1356	 * from the device. If focus CPU is disabled then the hang goes
1357	 * away, oh well :-(
1358	 *
1359	 * [ This bug can be reproduced easily with a level-triggered
1360	 *   PCI Ne2000 networking cards and PII/PIII processors, dual
1361	 *   BX chipset. ]
1362	 */
1363	/*
1364	 * Actually disabling the focus CPU check just makes the hang less
1365	 * frequent as it makes the interrupt distributon model be more
1366	 * like LRU than MRU (the short-term load is more even across CPUs).
1367	 * See also the comment in end_level_ioapic_irq().  --macro
1368	 */
1369
1370	/*
1371	 * - enable focus processor (bit==0)
1372	 * - 64bit mode always use processor focus
1373	 *   so no need to set it
1374	 */
1375	value &= ~APIC_SPIV_FOCUS_DISABLED;
1376#endif
1377
1378	/*
1379	 * Set spurious IRQ vector
1380	 */
1381	value |= SPURIOUS_APIC_VECTOR;
1382	apic_write(APIC_SPIV, value);
1383
1384	/*
1385	 * Set up LVT0, LVT1:
1386	 *
1387	 * set up through-local-APIC on the BP's LINT0. This is not
1388	 * strictly necessary in pure symmetric-IO mode, but sometimes
1389	 * we delegate interrupts to the 8259A.
1390	 */
1391	/*
1392	 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1393	 */
1394	value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1395	if (!cpu && (pic_mode || !value)) {
1396		value = APIC_DM_EXTINT;
1397		apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1398	} else {
1399		value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1400		apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1401	}
1402	apic_write(APIC_LVT0, value);
1403
1404	/*
1405	 * only the BP should see the LINT1 NMI signal, obviously.
 
1406	 */
1407	if (!cpu)
 
1408		value = APIC_DM_NMI;
1409	else
1410		value = APIC_DM_NMI | APIC_LVT_MASKED;
1411	if (!lapic_is_integrated())		/* 82489DX */
1412		value |= APIC_LVT_LEVEL_TRIGGER;
1413	apic_write(APIC_LVT1, value);
1414
1415#ifdef CONFIG_X86_MCE_INTEL
1416	/* Recheck CMCI information after local APIC is up on CPU #0 */
1417	if (!cpu)
1418		cmci_recheck();
1419#endif
1420}
1421
1422void __cpuinit end_local_APIC_setup(void)
1423{
1424	lapic_setup_esr();
1425
1426#ifdef CONFIG_X86_32
1427	{
1428		unsigned int value;
1429		/* Disable the local apic timer */
1430		value = apic_read(APIC_LVTT);
1431		value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1432		apic_write(APIC_LVTT, value);
1433	}
1434#endif
1435
1436	apic_pm_activate();
1437}
1438
1439void __init bsp_end_local_APIC_setup(void)
 
 
 
1440{
 
1441	end_local_APIC_setup();
1442
1443	/*
1444	 * Now that local APIC setup is completed for BP, configure the fault
1445	 * handling for interrupt remapping.
1446	 */
1447	if (irq_remapping_enabled)
1448		irq_remap_enable_fault_handling();
1449
1450}
1451
1452#ifdef CONFIG_X86_X2APIC
1453/*
1454 * Need to disable xapic and x2apic at the same time and then enable xapic mode
1455 */
1456static inline void __disable_x2apic(u64 msr)
1457{
1458	wrmsrl(MSR_IA32_APICBASE,
1459	       msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1460	wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1461}
1462
1463static __init void disable_x2apic(void)
1464{
1465	u64 msr;
1466
1467	if (!cpu_has_x2apic)
1468		return;
1469
1470	rdmsrl(MSR_IA32_APICBASE, msr);
1471	if (msr & X2APIC_ENABLE) {
1472		u32 x2apic_id = read_apic_id();
1473
1474		if (x2apic_id >= 255)
1475			panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
 
 
1476
1477		pr_info("Disabling x2apic\n");
1478		__disable_x2apic(msr);
 
1479
1480		if (nox2apic) {
1481			clear_cpu_cap(&cpu_data(0), X86_FEATURE_X2APIC);
1482			setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1483		}
 
 
1484
1485		x2apic_disabled = 1;
1486		x2apic_mode = 0;
 
 
1487
1488		register_lapic_address(mp_lapic_addr);
 
 
 
 
 
 
1489	}
 
 
 
 
1490}
 
1491
1492void check_x2apic(void)
 
1493{
1494	if (x2apic_enabled()) {
1495		pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
1496		x2apic_preenabled = x2apic_mode = 1;
 
 
 
 
1497	}
 
1498}
1499
1500void enable_x2apic(void)
1501{
1502	u64 msr;
1503
1504	rdmsrl(MSR_IA32_APICBASE, msr);
1505	if (x2apic_disabled) {
1506		__disable_x2apic(msr);
 
1507		return;
1508	}
1509
1510	if (!x2apic_mode)
 
 
 
 
 
 
 
 
 
 
1511		return;
1512
1513	if (!(msr & X2APIC_ENABLE)) {
1514		printk_once(KERN_INFO "Enabling x2apic\n");
1515		wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1516	}
 
1517}
1518#endif /* CONFIG_X86_X2APIC */
1519
1520int __init enable_IR(void)
1521{
1522#ifdef CONFIG_IRQ_REMAP
1523	if (!irq_remapping_supported()) {
1524		pr_debug("intr-remapping not supported\n");
1525		return -1;
 
 
1526	}
 
 
 
 
 
 
 
 
 
 
 
 
1527
1528	if (!x2apic_preenabled && skip_ioapic_setup) {
1529		pr_info("Skipped enabling intr-remap because of skipping "
1530			"io-apic setup\n");
 
 
 
 
 
 
1531		return -1;
1532	}
1533
1534	return irq_remapping_enable();
1535#endif
1536	return -1;
1537}
1538
1539void __init enable_IR_x2apic(void)
1540{
1541	unsigned long flags;
1542	int ret, x2apic_enabled = 0;
1543	int hardware_init_ret;
1544
1545	/* Make sure irq_remap_ops are initialized */
1546	setup_irq_remapping_ops();
1547
1548	hardware_init_ret = irq_remapping_prepare();
1549	if (hardware_init_ret && !x2apic_supported())
1550		return;
1551
1552	ret = save_ioapic_entries();
1553	if (ret) {
1554		pr_info("Saving IO-APIC state failed: %d\n", ret);
1555		return;
1556	}
1557
1558	local_irq_save(flags);
1559	legacy_pic->mask_all();
1560	mask_ioapic_entries();
1561
1562	if (x2apic_preenabled && nox2apic)
1563		disable_x2apic();
1564
1565	if (hardware_init_ret)
1566		ret = -1;
1567	else
1568		ret = enable_IR();
1569
1570	if (!x2apic_supported())
1571		goto skip_x2apic;
1572
1573	if (ret < 0) {
1574		/* IR is required if there is APIC ID > 255 even when running
1575		 * under KVM
1576		 */
1577		if (max_physical_apicid > 255 ||
1578		    !hypervisor_x2apic_available()) {
1579			if (x2apic_preenabled)
1580				disable_x2apic();
1581			goto skip_x2apic;
1582		}
1583		/*
1584		 * without IR all CPUs can be addressed by IOAPIC/MSI
1585		 * only in physical mode
1586		 */
1587		x2apic_force_phys();
1588	}
1589
1590	if (ret == IRQ_REMAP_XAPIC_MODE) {
1591		pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n");
1592		goto skip_x2apic;
1593	}
1594
1595	x2apic_enabled = 1;
1596
1597	if (x2apic_supported() && !x2apic_mode) {
1598		x2apic_mode = 1;
1599		enable_x2apic();
1600		pr_info("Enabled x2apic\n");
1601	}
1602
1603skip_x2apic:
1604	if (ret < 0) /* IR enabling failed */
1605		restore_ioapic_entries();
1606	legacy_pic->restore_mask();
1607	local_irq_restore(flags);
1608}
1609
1610#ifdef CONFIG_X86_64
1611/*
1612 * Detect and enable local APICs on non-SMP boards.
1613 * Original code written by Keir Fraser.
1614 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1615 * not correctly set up (usually the APIC timer won't work etc.)
1616 */
1617static int __init detect_init_APIC(void)
1618{
1619	if (!cpu_has_apic) {
1620		pr_info("No local APIC present\n");
1621		return -1;
1622	}
1623
1624	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1625	return 0;
1626}
1627#else
1628
1629static int __init apic_verify(void)
1630{
1631	u32 features, h, l;
1632
1633	/*
1634	 * The APIC feature bit should now be enabled
1635	 * in `cpuid'
1636	 */
1637	features = cpuid_edx(1);
1638	if (!(features & (1 << X86_FEATURE_APIC))) {
1639		pr_warning("Could not enable APIC!\n");
1640		return -1;
1641	}
1642	set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1643	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1644
1645	/* The BIOS may have set up the APIC at some other address */
1646	if (boot_cpu_data.x86 >= 6) {
1647		rdmsr(MSR_IA32_APICBASE, l, h);
1648		if (l & MSR_IA32_APICBASE_ENABLE)
1649			mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1650	}
1651
1652	pr_info("Found and enabled local APIC!\n");
1653	return 0;
1654}
1655
1656int __init apic_force_enable(unsigned long addr)
1657{
1658	u32 h, l;
1659
1660	if (disable_apic)
1661		return -1;
1662
1663	/*
1664	 * Some BIOSes disable the local APIC in the APIC_BASE
1665	 * MSR. This can only be done in software for Intel P6 or later
1666	 * and AMD K7 (Model > 1) or later.
1667	 */
1668	if (boot_cpu_data.x86 >= 6) {
1669		rdmsr(MSR_IA32_APICBASE, l, h);
1670		if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1671			pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1672			l &= ~MSR_IA32_APICBASE_BASE;
1673			l |= MSR_IA32_APICBASE_ENABLE | addr;
1674			wrmsr(MSR_IA32_APICBASE, l, h);
1675			enabled_via_apicbase = 1;
1676		}
1677	}
1678	return apic_verify();
1679}
1680
1681/*
1682 * Detect and initialize APIC
1683 */
1684static int __init detect_init_APIC(void)
1685{
1686	/* Disabled by kernel option? */
1687	if (disable_apic)
1688		return -1;
1689
1690	switch (boot_cpu_data.x86_vendor) {
1691	case X86_VENDOR_AMD:
1692		if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1693		    (boot_cpu_data.x86 >= 15))
1694			break;
1695		goto no_apic;
1696	case X86_VENDOR_INTEL:
1697		if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1698		    (boot_cpu_data.x86 == 5 && cpu_has_apic))
1699			break;
1700		goto no_apic;
1701	default:
1702		goto no_apic;
1703	}
1704
1705	if (!cpu_has_apic) {
1706		/*
1707		 * Over-ride BIOS and try to enable the local APIC only if
1708		 * "lapic" specified.
1709		 */
1710		if (!force_enable_local_apic) {
1711			pr_info("Local APIC disabled by BIOS -- "
1712				"you can enable it with \"lapic\"\n");
1713			return -1;
1714		}
1715		if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
1716			return -1;
1717	} else {
1718		if (apic_verify())
1719			return -1;
1720	}
1721
1722	apic_pm_activate();
1723
1724	return 0;
1725
1726no_apic:
1727	pr_info("No local APIC present or hardware disabled\n");
1728	return -1;
1729}
1730#endif
1731
1732/**
1733 * init_apic_mappings - initialize APIC mappings
1734 */
1735void __init init_apic_mappings(void)
1736{
1737	unsigned int new_apicid;
1738
1739	if (x2apic_mode) {
1740		boot_cpu_physical_apicid = read_apic_id();
1741		return;
1742	}
1743
1744	/* If no local APIC can be found return early */
1745	if (!smp_found_config && detect_init_APIC()) {
1746		/* lets NOP'ify apic operations */
1747		pr_info("APIC: disable apic facility\n");
1748		apic_disable();
1749	} else {
1750		apic_phys = mp_lapic_addr;
1751
1752		/*
1753		 * acpi lapic path already maps that address in
1754		 * acpi_register_lapic_address()
1755		 */
1756		if (!acpi_lapic && !smp_found_config)
1757			register_lapic_address(apic_phys);
1758	}
1759
1760	/*
1761	 * Fetch the APIC ID of the BSP in case we have a
1762	 * default configuration (or the MP table is broken).
1763	 */
1764	new_apicid = read_apic_id();
1765	if (boot_cpu_physical_apicid != new_apicid) {
1766		boot_cpu_physical_apicid = new_apicid;
1767		/*
1768		 * yeah -- we lie about apic_version
1769		 * in case if apic was disabled via boot option
1770		 * but it's not a problem for SMP compiled kernel
1771		 * since smp_sanity_check is prepared for such a case
1772		 * and disable smp mode
1773		 */
1774		apic_version[new_apicid] =
1775			 GET_APIC_VERSION(apic_read(APIC_LVR));
1776	}
1777}
1778
1779void __init register_lapic_address(unsigned long address)
1780{
1781	mp_lapic_addr = address;
1782
1783	if (!x2apic_mode) {
1784		set_fixmap_nocache(FIX_APIC_BASE, address);
1785		apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1786			    APIC_BASE, mp_lapic_addr);
1787	}
1788	if (boot_cpu_physical_apicid == -1U) {
1789		boot_cpu_physical_apicid  = read_apic_id();
1790		apic_version[boot_cpu_physical_apicid] =
1791			 GET_APIC_VERSION(apic_read(APIC_LVR));
1792	}
1793}
1794
1795/*
1796 * This initializes the IO-APIC and APIC hardware if this is
1797 * a UP kernel.
1798 */
1799int apic_version[MAX_LOCAL_APIC];
1800
1801int __init APIC_init_uniprocessor(void)
1802{
1803	if (disable_apic) {
1804		pr_info("Apic disabled\n");
1805		return -1;
1806	}
1807#ifdef CONFIG_X86_64
1808	if (!cpu_has_apic) {
1809		disable_apic = 1;
1810		pr_info("Apic disabled by BIOS\n");
1811		return -1;
1812	}
1813#else
1814	if (!smp_found_config && !cpu_has_apic)
1815		return -1;
1816
1817	/*
1818	 * Complain if the BIOS pretends there is one.
1819	 */
1820	if (!cpu_has_apic &&
1821	    APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
1822		pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
1823			boot_cpu_physical_apicid);
1824		return -1;
1825	}
1826#endif
1827
1828	default_setup_apic_routing();
1829
1830	verify_local_APIC();
1831	connect_bsp_APIC();
1832
1833#ifdef CONFIG_X86_64
1834	apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
1835#else
1836	/*
1837	 * Hack: In case of kdump, after a crash, kernel might be booting
1838	 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
1839	 * might be zero if read from MP tables. Get it from LAPIC.
1840	 */
1841# ifdef CONFIG_CRASH_DUMP
1842	boot_cpu_physical_apicid = read_apic_id();
1843# endif
1844#endif
1845	physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1846	setup_local_APIC();
1847
1848#ifdef CONFIG_X86_IO_APIC
1849	/*
1850	 * Now enable IO-APICs, actually call clear_IO_APIC
1851	 * We need clear_IO_APIC before enabling error vector
1852	 */
1853	if (!skip_ioapic_setup && nr_ioapics)
1854		enable_IO_APIC();
1855#endif
1856
1857	bsp_end_local_APIC_setup();
1858
1859#ifdef CONFIG_X86_IO_APIC
1860	if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
1861		setup_IO_APIC();
1862	else {
1863		nr_ioapics = 0;
1864	}
1865#endif
1866
1867	x86_init.timers.setup_percpu_clockev();
1868	return 0;
1869}
1870
1871/*
1872 * Local APIC interrupts
1873 */
1874
1875/*
1876 * This interrupt should _never_ happen with our APIC/SMP architecture
1877 */
1878void smp_spurious_interrupt(struct pt_regs *regs)
1879{
1880	u32 v;
1881
1882	irq_enter();
1883	exit_idle();
1884	/*
1885	 * Check if this really is a spurious interrupt and ACK it
1886	 * if it is a vectored one.  Just in case...
1887	 * Spurious interrupts should not be ACKed.
1888	 */
1889	v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
1890	if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
1891		ack_APIC_irq();
1892
1893	inc_irq_stat(irq_spurious_count);
1894
1895	/* see sw-dev-man vol 3, chapter 7.4.13.5 */
1896	pr_info("spurious APIC interrupt on CPU#%d, "
1897		"should never happen.\n", smp_processor_id());
1898	irq_exit();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1899}
1900
1901/*
1902 * This interrupt should never happen with our APIC/SMP architecture
1903 */
1904void smp_error_interrupt(struct pt_regs *regs)
1905{
1906	u32 v0, v1;
1907	u32 i = 0;
1908	static const char * const error_interrupt_reason[] = {
1909		"Send CS error",		/* APIC Error Bit 0 */
1910		"Receive CS error",		/* APIC Error Bit 1 */
1911		"Send accept error",		/* APIC Error Bit 2 */
1912		"Receive accept error",		/* APIC Error Bit 3 */
1913		"Redirectable IPI",		/* APIC Error Bit 4 */
1914		"Send illegal vector",		/* APIC Error Bit 5 */
1915		"Received illegal vector",	/* APIC Error Bit 6 */
1916		"Illegal register address",	/* APIC Error Bit 7 */
1917	};
1918
1919	irq_enter();
1920	exit_idle();
1921	/* First tickle the hardware, only then report what went on. -- REW */
1922	v0 = apic_read(APIC_ESR);
1923	apic_write(APIC_ESR, 0);
1924	v1 = apic_read(APIC_ESR);
1925	ack_APIC_irq();
1926	atomic_inc(&irq_err_count);
1927
1928	apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x(%02x)",
1929		    smp_processor_id(), v0 , v1);
1930
1931	v1 = v1 & 0xff;
1932	while (v1) {
1933		if (v1 & 0x1)
1934			apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
1935		i++;
1936		v1 >>= 1;
1937	};
1938
1939	apic_printk(APIC_DEBUG, KERN_CONT "\n");
1940
1941	irq_exit();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1942}
1943
1944/**
1945 * connect_bsp_APIC - attach the APIC to the interrupt system
1946 */
1947void __init connect_bsp_APIC(void)
1948{
1949#ifdef CONFIG_X86_32
1950	if (pic_mode) {
1951		/*
1952		 * Do not trust the local APIC being empty at bootup.
1953		 */
1954		clear_local_APIC();
1955		/*
1956		 * PIC mode, enable APIC mode in the IMCR, i.e.  connect BSP's
1957		 * local APIC to INT and NMI lines.
1958		 */
1959		apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1960				"enabling APIC mode.\n");
1961		imcr_pic_to_apic();
1962	}
1963#endif
1964	if (apic->enable_apic_mode)
1965		apic->enable_apic_mode();
1966}
1967
1968/**
1969 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1970 * @virt_wire_setup:	indicates, whether virtual wire mode is selected
1971 *
1972 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1973 * APIC is disabled.
1974 */
1975void disconnect_bsp_APIC(int virt_wire_setup)
1976{
1977	unsigned int value;
1978
1979#ifdef CONFIG_X86_32
1980	if (pic_mode) {
1981		/*
1982		 * Put the board back into PIC mode (has an effect only on
1983		 * certain older boards).  Note that APIC interrupts, including
1984		 * IPIs, won't work beyond this point!  The only exception are
1985		 * INIT IPIs.
1986		 */
1987		apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1988				"entering PIC mode.\n");
1989		imcr_apic_to_pic();
1990		return;
1991	}
1992#endif
1993
1994	/* Go back to Virtual Wire compatibility mode */
1995
1996	/* For the spurious interrupt use vector F, and enable it */
1997	value = apic_read(APIC_SPIV);
1998	value &= ~APIC_VECTOR_MASK;
1999	value |= APIC_SPIV_APIC_ENABLED;
2000	value |= 0xf;
2001	apic_write(APIC_SPIV, value);
2002
2003	if (!virt_wire_setup) {
2004		/*
2005		 * For LVT0 make it edge triggered, active high,
2006		 * external and enabled
2007		 */
2008		value = apic_read(APIC_LVT0);
2009		value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2010			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2011			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2012		value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2013		value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
2014		apic_write(APIC_LVT0, value);
2015	} else {
2016		/* Disable LVT0 */
2017		apic_write(APIC_LVT0, APIC_LVT_MASKED);
2018	}
2019
2020	/*
2021	 * For LVT1 make it edge triggered, active high,
2022	 * nmi and enabled
2023	 */
2024	value = apic_read(APIC_LVT1);
2025	value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
2026			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
2027			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
2028	value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
2029	value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
2030	apic_write(APIC_LVT1, value);
2031}
2032
2033void __cpuinit generic_processor_info(int apicid, int version)
2034{
2035	int cpu, max = nr_cpu_ids;
2036	bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
2037				phys_cpu_present_map);
2038
2039	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2040	 * If boot cpu has not been detected yet, then only allow upto
2041	 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu
2042	 */
2043	if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
2044	    apicid != boot_cpu_physical_apicid) {
2045		int thiscpu = max + disabled_cpus - 1;
2046
2047		pr_warning(
2048			"ACPI: NR_CPUS/possible_cpus limit of %i almost"
2049			" reached. Keeping one slot for boot cpu."
2050			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2051
2052		disabled_cpus++;
2053		return;
2054	}
2055
2056	if (num_processors >= nr_cpu_ids) {
2057		int thiscpu = max + disabled_cpus;
2058
2059		pr_warning(
2060			"ACPI: NR_CPUS/possible_cpus limit of %i reached."
2061			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2062
2063		disabled_cpus++;
2064		return;
2065	}
2066
2067	num_processors++;
2068	if (apicid == boot_cpu_physical_apicid) {
2069		/*
2070		 * x86_bios_cpu_apicid is required to have processors listed
2071		 * in same order as logical cpu numbers. Hence the first
2072		 * entry is BSP, and so on.
2073		 * boot_cpu_init() already hold bit 0 in cpu_present_mask
2074		 * for BSP.
2075		 */
2076		cpu = 0;
2077	} else
2078		cpu = cpumask_next_zero(-1, cpu_present_mask);
2079
2080	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2081	 * Validate version
2082	 */
2083	if (version == 0x0) {
2084		pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
2085			   cpu, apicid);
2086		version = 0x10;
2087	}
2088	apic_version[apicid] = version;
2089
2090	if (version != apic_version[boot_cpu_physical_apicid]) {
2091		pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
2092			apic_version[boot_cpu_physical_apicid], cpu, version);
2093	}
2094
2095	physid_set(apicid, phys_cpu_present_map);
2096	if (apicid > max_physical_apicid)
2097		max_physical_apicid = apicid;
2098
2099#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2100	early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2101	early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
2102#endif
2103#ifdef CONFIG_X86_32
2104	early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
2105		apic->x86_32_early_logical_apicid(cpu);
2106#endif
2107	set_cpu_possible(cpu, true);
2108	set_cpu_present(cpu, true);
 
 
2109}
2110
2111int hard_smp_processor_id(void)
2112{
2113	return read_apic_id();
2114}
2115
2116void default_init_apic_ldr(void)
2117{
2118	unsigned long val;
2119
2120	apic_write(APIC_DFR, APIC_DFR_VALUE);
2121	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
2122	val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
2123	apic_write(APIC_LDR, val);
2124}
2125
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2126/*
2127 * Power management
2128 */
2129#ifdef CONFIG_PM
2130
2131static struct {
2132	/*
2133	 * 'active' is true if the local APIC was enabled by us and
2134	 * not the BIOS; this signifies that we are also responsible
2135	 * for disabling it before entering apm/acpi suspend
2136	 */
2137	int active;
2138	/* r/w apic fields */
2139	unsigned int apic_id;
2140	unsigned int apic_taskpri;
2141	unsigned int apic_ldr;
2142	unsigned int apic_dfr;
2143	unsigned int apic_spiv;
2144	unsigned int apic_lvtt;
2145	unsigned int apic_lvtpc;
2146	unsigned int apic_lvt0;
2147	unsigned int apic_lvt1;
2148	unsigned int apic_lvterr;
2149	unsigned int apic_tmict;
2150	unsigned int apic_tdcr;
2151	unsigned int apic_thmr;
 
2152} apic_pm_state;
2153
2154static int lapic_suspend(void)
2155{
2156	unsigned long flags;
2157	int maxlvt;
2158
2159	if (!apic_pm_state.active)
2160		return 0;
2161
2162	maxlvt = lapic_get_maxlvt();
2163
2164	apic_pm_state.apic_id = apic_read(APIC_ID);
2165	apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2166	apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2167	apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2168	apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2169	apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2170	if (maxlvt >= 4)
2171		apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2172	apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2173	apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2174	apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2175	apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2176	apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2177#ifdef CONFIG_X86_THERMAL_VECTOR
2178	if (maxlvt >= 5)
2179		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2180#endif
 
 
 
 
2181
2182	local_irq_save(flags);
2183	disable_local_APIC();
2184
2185	if (irq_remapping_enabled)
2186		irq_remapping_disable();
2187
2188	local_irq_restore(flags);
2189	return 0;
2190}
2191
2192static void lapic_resume(void)
2193{
2194	unsigned int l, h;
2195	unsigned long flags;
2196	int maxlvt;
2197
2198	if (!apic_pm_state.active)
2199		return;
2200
2201	local_irq_save(flags);
2202	if (irq_remapping_enabled) {
2203		/*
2204		 * IO-APIC and PIC have their own resume routines.
2205		 * We just mask them here to make sure the interrupt
2206		 * subsystem is completely quiet while we enable x2apic
2207		 * and interrupt-remapping.
2208		 */
2209		mask_ioapic_entries();
2210		legacy_pic->mask_all();
2211	}
2212
2213	if (x2apic_mode)
2214		enable_x2apic();
2215	else {
 
 
 
 
 
 
 
 
 
2216		/*
2217		 * Make sure the APICBASE points to the right address
2218		 *
2219		 * FIXME! This will be wrong if we ever support suspend on
2220		 * SMP! We'll need to do this as part of the CPU restore!
2221		 */
2222		if (boot_cpu_data.x86 >= 6) {
2223			rdmsr(MSR_IA32_APICBASE, l, h);
2224			l &= ~MSR_IA32_APICBASE_BASE;
2225			l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2226			wrmsr(MSR_IA32_APICBASE, l, h);
2227		}
2228	}
2229
2230	maxlvt = lapic_get_maxlvt();
2231	apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2232	apic_write(APIC_ID, apic_pm_state.apic_id);
2233	apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2234	apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2235	apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2236	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2237	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2238	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2239#if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
2240	if (maxlvt >= 5)
2241		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2242#endif
 
 
 
 
2243	if (maxlvt >= 4)
2244		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2245	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2246	apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2247	apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2248	apic_write(APIC_ESR, 0);
2249	apic_read(APIC_ESR);
2250	apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2251	apic_write(APIC_ESR, 0);
2252	apic_read(APIC_ESR);
2253
2254	if (irq_remapping_enabled)
2255		irq_remapping_reenable(x2apic_mode);
2256
2257	local_irq_restore(flags);
2258}
2259
2260/*
2261 * This device has no shutdown method - fully functioning local APICs
2262 * are needed on every CPU up until machine_halt/restart/poweroff.
2263 */
2264
2265static struct syscore_ops lapic_syscore_ops = {
2266	.resume		= lapic_resume,
2267	.suspend	= lapic_suspend,
2268};
2269
2270static void __cpuinit apic_pm_activate(void)
2271{
2272	apic_pm_state.active = 1;
2273}
2274
2275static int __init init_lapic_sysfs(void)
2276{
2277	/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2278	if (cpu_has_apic)
2279		register_syscore_ops(&lapic_syscore_ops);
2280
2281	return 0;
2282}
2283
2284/* local apic needs to resume before other devices access its registers. */
2285core_initcall(init_lapic_sysfs);
2286
2287#else	/* CONFIG_PM */
2288
2289static void apic_pm_activate(void) { }
2290
2291#endif	/* CONFIG_PM */
2292
2293#ifdef CONFIG_X86_64
2294
2295static int __cpuinit apic_cluster_num(void)
2296{
2297	int i, clusters, zeros;
2298	unsigned id;
2299	u16 *bios_cpu_apicid;
2300	DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
2301
2302	bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
2303	bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
2304
2305	for (i = 0; i < nr_cpu_ids; i++) {
2306		/* are we being called early in kernel startup? */
2307		if (bios_cpu_apicid) {
2308			id = bios_cpu_apicid[i];
2309		} else if (i < nr_cpu_ids) {
2310			if (cpu_present(i))
2311				id = per_cpu(x86_bios_cpu_apicid, i);
2312			else
2313				continue;
2314		} else
2315			break;
2316
2317		if (id != BAD_APICID)
2318			__set_bit(APIC_CLUSTERID(id), clustermap);
2319	}
2320
2321	/* Problem:  Partially populated chassis may not have CPUs in some of
2322	 * the APIC clusters they have been allocated.  Only present CPUs have
2323	 * x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
2324	 * Since clusters are allocated sequentially, count zeros only if
2325	 * they are bounded by ones.
2326	 */
2327	clusters = 0;
2328	zeros = 0;
2329	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
2330		if (test_bit(i, clustermap)) {
2331			clusters += 1 + zeros;
2332			zeros = 0;
2333		} else
2334			++zeros;
2335	}
2336
2337	return clusters;
2338}
2339
2340static int __cpuinitdata multi_checked;
2341static int __cpuinitdata multi;
2342
2343static int __cpuinit set_multi(const struct dmi_system_id *d)
2344{
2345	if (multi)
2346		return 0;
2347	pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2348	multi = 1;
2349	return 0;
2350}
2351
2352static const __cpuinitconst struct dmi_system_id multi_dmi_table[] = {
2353	{
2354		.callback = set_multi,
2355		.ident = "IBM System Summit2",
2356		.matches = {
2357			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2358			DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2359		},
2360	},
2361	{}
2362};
2363
2364static void __cpuinit dmi_check_multi(void)
2365{
2366	if (multi_checked)
2367		return;
2368
2369	dmi_check_system(multi_dmi_table);
2370	multi_checked = 1;
2371}
2372
2373/*
2374 * apic_is_clustered_box() -- Check if we can expect good TSC
2375 *
2376 * Thus far, the major user of this is IBM's Summit2 series:
2377 * Clustered boxes may have unsynced TSC problems if they are
2378 * multi-chassis.
2379 * Use DMI to check them
2380 */
2381__cpuinit int apic_is_clustered_box(void)
2382{
2383	dmi_check_multi();
2384	if (multi)
2385		return 1;
2386
2387	if (!is_vsmp_box())
2388		return 0;
2389
2390	/*
2391	 * ScaleMP vSMPowered boxes have one cluster per board and TSCs are
2392	 * not guaranteed to be synced between boards
2393	 */
2394	if (apic_cluster_num() > 1)
2395		return 1;
2396
2397	return 0;
2398}
2399#endif
2400
2401/*
2402 * APIC command line parameters
2403 */
2404static int __init setup_disableapic(char *arg)
2405{
2406	disable_apic = 1;
2407	setup_clear_cpu_cap(X86_FEATURE_APIC);
2408	return 0;
2409}
2410early_param("disableapic", setup_disableapic);
2411
2412/* same as disableapic, for compatibility */
2413static int __init setup_nolapic(char *arg)
2414{
2415	return setup_disableapic(arg);
2416}
2417early_param("nolapic", setup_nolapic);
2418
2419static int __init parse_lapic_timer_c2_ok(char *arg)
2420{
2421	local_apic_timer_c2_ok = 1;
2422	return 0;
2423}
2424early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2425
2426static int __init parse_disable_apic_timer(char *arg)
2427{
2428	disable_apic_timer = 1;
2429	return 0;
2430}
2431early_param("noapictimer", parse_disable_apic_timer);
2432
2433static int __init parse_nolapic_timer(char *arg)
2434{
2435	disable_apic_timer = 1;
2436	return 0;
2437}
2438early_param("nolapic_timer", parse_nolapic_timer);
2439
2440static int __init apic_set_verbosity(char *arg)
2441{
2442	if (!arg)  {
2443#ifdef CONFIG_X86_64
2444		skip_ioapic_setup = 0;
2445		return 0;
2446#endif
2447		return -EINVAL;
2448	}
2449
2450	if (strcmp("debug", arg) == 0)
2451		apic_verbosity = APIC_DEBUG;
2452	else if (strcmp("verbose", arg) == 0)
2453		apic_verbosity = APIC_VERBOSE;
2454	else {
2455		pr_warning("APIC Verbosity level %s not recognised"
2456			" use apic=verbose or apic=debug\n", arg);
2457		return -EINVAL;
2458	}
2459
2460	return 0;
2461}
2462early_param("apic", apic_set_verbosity);
2463
2464static int __init lapic_insert_resource(void)
2465{
2466	if (!apic_phys)
2467		return -1;
2468
2469	/* Put local APIC into the resource map. */
2470	lapic_resource.start = apic_phys;
2471	lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2472	insert_resource(&iomem_resource, &lapic_resource);
2473
2474	return 0;
2475}
2476
2477/*
2478 * need call insert after e820_reserve_resources()
2479 * that is using request_resource
2480 */
2481late_initcall(lapic_insert_resource);
v4.6
   1/*
   2 *	Local APIC handling, local APIC timers
   3 *
   4 *	(c) 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
   5 *
   6 *	Fixes
   7 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
   8 *					thanks to Eric Gilmore
   9 *					and Rolf G. Tews
  10 *					for testing these extensively.
  11 *	Maciej W. Rozycki	:	Various updates and fixes.
  12 *	Mikael Pettersson	:	Power Management for UP-APIC.
  13 *	Pavel Machek and
  14 *	Mikael Pettersson	:	PM converted to driver model.
  15 */
  16
  17#include <linux/perf_event.h>
  18#include <linux/kernel_stat.h>
  19#include <linux/mc146818rtc.h>
  20#include <linux/acpi_pmtmr.h>
  21#include <linux/clockchips.h>
  22#include <linux/interrupt.h>
  23#include <linux/bootmem.h>
  24#include <linux/ftrace.h>
  25#include <linux/ioport.h>
  26#include <linux/module.h>
  27#include <linux/syscore_ops.h>
  28#include <linux/delay.h>
  29#include <linux/timex.h>
  30#include <linux/i8253.h>
  31#include <linux/dmar.h>
  32#include <linux/init.h>
  33#include <linux/cpu.h>
  34#include <linux/dmi.h>
  35#include <linux/smp.h>
  36#include <linux/mm.h>
  37
  38#include <asm/trace/irq_vectors.h>
  39#include <asm/irq_remapping.h>
  40#include <asm/perf_event.h>
  41#include <asm/x86_init.h>
  42#include <asm/pgalloc.h>
  43#include <linux/atomic.h>
  44#include <asm/mpspec.h>
  45#include <asm/i8259.h>
  46#include <asm/proto.h>
  47#include <asm/apic.h>
  48#include <asm/io_apic.h>
  49#include <asm/desc.h>
  50#include <asm/hpet.h>
  51#include <asm/idle.h>
  52#include <asm/mtrr.h>
  53#include <asm/time.h>
  54#include <asm/smp.h>
  55#include <asm/mce.h>
  56#include <asm/tsc.h>
  57#include <asm/hypervisor.h>
  58
  59unsigned int num_processors;
  60
  61unsigned disabled_cpus;
  62
  63/* Processor that is doing the boot up */
  64unsigned int boot_cpu_physical_apicid = -1U;
  65EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
  66
  67/*
  68 * The highest APIC ID seen during enumeration.
  69 */
  70static unsigned int max_physical_apicid;
  71
  72/*
  73 * Bitmask of physically existing CPUs:
  74 */
  75physid_mask_t phys_cpu_present_map;
  76
  77/*
  78 * Processor to be disabled specified by kernel parameter
  79 * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
  80 * avoid undefined behaviour caused by sending INIT from AP to BSP.
  81 */
  82static unsigned int disabled_cpu_apicid __read_mostly = BAD_APICID;
  83
  84/*
  85 * This variable controls which CPUs receive external NMIs.  By default,
  86 * external NMIs are delivered only to the BSP.
  87 */
  88static int apic_extnmi = APIC_EXTNMI_BSP;
  89
  90/*
  91 * Map cpu index to physical APIC ID
  92 */
  93DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
  94DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID);
  95EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
  96EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
  97
  98#ifdef CONFIG_X86_32
  99
 100/*
 101 * On x86_32, the mapping between cpu and logical apicid may vary
 102 * depending on apic in use.  The following early percpu variable is
 103 * used for the mapping.  This is where the behaviors of x86_64 and 32
 104 * actually diverge.  Let's keep it ugly for now.
 105 */
 106DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID);
 107
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 108/* Local APIC was disabled by the BIOS and enabled by the kernel */
 109static int enabled_via_apicbase;
 110
 111/*
 112 * Handle interrupt mode configuration register (IMCR).
 113 * This register controls whether the interrupt signals
 114 * that reach the BSP come from the master PIC or from the
 115 * local APIC. Before entering Symmetric I/O Mode, either
 116 * the BIOS or the operating system must switch out of
 117 * PIC Mode by changing the IMCR.
 118 */
 119static inline void imcr_pic_to_apic(void)
 120{
 121	/* select IMCR register */
 122	outb(0x70, 0x22);
 123	/* NMI and 8259 INTR go through APIC */
 124	outb(0x01, 0x23);
 125}
 126
 127static inline void imcr_apic_to_pic(void)
 128{
 129	/* select IMCR register */
 130	outb(0x70, 0x22);
 131	/* NMI and 8259 INTR go directly to BSP */
 132	outb(0x00, 0x23);
 133}
 134#endif
 135
 136/*
 137 * Knob to control our willingness to enable the local APIC.
 138 *
 139 * +1=force-enable
 140 */
 141static int force_enable_local_apic __initdata;
 142
 143/*
 144 * APIC command line parameters
 145 */
 146static int __init parse_lapic(char *arg)
 147{
 148	if (config_enabled(CONFIG_X86_32) && !arg)
 149		force_enable_local_apic = 1;
 150	else if (arg && !strncmp(arg, "notscdeadline", 13))
 151		setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
 152	return 0;
 153}
 154early_param("lapic", parse_lapic);
 155
 156#ifdef CONFIG_X86_64
 157static int apic_calibrate_pmtmr __initdata;
 158static __init int setup_apicpmtimer(char *s)
 159{
 160	apic_calibrate_pmtmr = 1;
 161	notsc_setup(NULL);
 162	return 0;
 163}
 164__setup("apicpmtimer", setup_apicpmtimer);
 165#endif
 166
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 167unsigned long mp_lapic_addr;
 168int disable_apic;
 169/* Disable local APIC timer from the kernel commandline or via dmi quirk */
 170static int disable_apic_timer __initdata;
 171/* Local APIC timer works in C2 */
 172int local_apic_timer_c2_ok;
 173EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
 174
 175int first_system_vector = FIRST_SYSTEM_VECTOR;
 176
 177/*
 178 * Debug level, exported for io_apic.c
 179 */
 180unsigned int apic_verbosity;
 181
 182int pic_mode;
 183
 184/* Have we found an MP table */
 185int smp_found_config;
 186
 187static struct resource lapic_resource = {
 188	.name = "Local APIC",
 189	.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
 190};
 191
 192unsigned int lapic_timer_frequency = 0;
 193
 194static void apic_pm_activate(void);
 195
 196static unsigned long apic_phys;
 197
 198/*
 199 * Get the LAPIC version
 200 */
 201static inline int lapic_get_version(void)
 202{
 203	return GET_APIC_VERSION(apic_read(APIC_LVR));
 204}
 205
 206/*
 207 * Check, if the APIC is integrated or a separate chip
 208 */
 209static inline int lapic_is_integrated(void)
 210{
 211#ifdef CONFIG_X86_64
 212	return 1;
 213#else
 214	return APIC_INTEGRATED(lapic_get_version());
 215#endif
 216}
 217
 218/*
 219 * Check, whether this is a modern or a first generation APIC
 220 */
 221static int modern_apic(void)
 222{
 223	/* AMD systems use old APIC versions, so check the CPU */
 224	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 225	    boot_cpu_data.x86 >= 0xf)
 226		return 1;
 227	return lapic_get_version() >= 0x14;
 228}
 229
 230/*
 231 * right after this call apic become NOOP driven
 232 * so apic->write/read doesn't do anything
 233 */
 234static void __init apic_disable(void)
 235{
 236	pr_info("APIC: switched to apic NOOP\n");
 237	apic = &apic_noop;
 238}
 239
 240void native_apic_wait_icr_idle(void)
 241{
 242	while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
 243		cpu_relax();
 244}
 245
 246u32 native_safe_apic_wait_icr_idle(void)
 247{
 248	u32 send_status;
 249	int timeout;
 250
 251	timeout = 0;
 252	do {
 253		send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
 254		if (!send_status)
 255			break;
 256		inc_irq_stat(icr_read_retry_count);
 257		udelay(100);
 258	} while (timeout++ < 1000);
 259
 260	return send_status;
 261}
 262
 263void native_apic_icr_write(u32 low, u32 id)
 264{
 265	unsigned long flags;
 266
 267	local_irq_save(flags);
 268	apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
 269	apic_write(APIC_ICR, low);
 270	local_irq_restore(flags);
 271}
 272
 273u64 native_apic_icr_read(void)
 274{
 275	u32 icr1, icr2;
 276
 277	icr2 = apic_read(APIC_ICR2);
 278	icr1 = apic_read(APIC_ICR);
 279
 280	return icr1 | ((u64)icr2 << 32);
 281}
 282
 283#ifdef CONFIG_X86_32
 284/**
 285 * get_physical_broadcast - Get number of physical broadcast IDs
 286 */
 287int get_physical_broadcast(void)
 288{
 289	return modern_apic() ? 0xff : 0xf;
 290}
 291#endif
 292
 293/**
 294 * lapic_get_maxlvt - get the maximum number of local vector table entries
 295 */
 296int lapic_get_maxlvt(void)
 297{
 298	unsigned int v;
 299
 300	v = apic_read(APIC_LVR);
 301	/*
 302	 * - we always have APIC integrated on 64bit mode
 303	 * - 82489DXs do not report # of LVT entries
 304	 */
 305	return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
 306}
 307
 308/*
 309 * Local APIC timer
 310 */
 311
 312/* Clock divisor */
 313#define APIC_DIVISOR 16
 314#define TSC_DIVISOR  32
 315
 316/*
 317 * This function sets up the local APIC timer, with a timeout of
 318 * 'clocks' APIC bus clock. During calibration we actually call
 319 * this function twice on the boot CPU, once with a bogus timeout
 320 * value, second time for real. The other (noncalibrating) CPUs
 321 * call this function only once, with the real, calibrated value.
 322 *
 323 * We do reads before writes even if unnecessary, to get around the
 324 * P5 APIC double write bug.
 325 */
 326static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
 327{
 328	unsigned int lvtt_value, tmp_value;
 329
 330	lvtt_value = LOCAL_TIMER_VECTOR;
 331	if (!oneshot)
 332		lvtt_value |= APIC_LVT_TIMER_PERIODIC;
 333	else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
 334		lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
 335
 336	if (!lapic_is_integrated())
 337		lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
 338
 339	if (!irqen)
 340		lvtt_value |= APIC_LVT_MASKED;
 341
 342	apic_write(APIC_LVTT, lvtt_value);
 343
 344	if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
 345		/*
 346		 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
 347		 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
 348		 * According to Intel, MFENCE can do the serialization here.
 349		 */
 350		asm volatile("mfence" : : : "memory");
 351
 352		printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
 353		return;
 354	}
 355
 356	/*
 357	 * Divide PICLK by 16
 358	 */
 359	tmp_value = apic_read(APIC_TDCR);
 360	apic_write(APIC_TDCR,
 361		(tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
 362		APIC_TDR_DIV_16);
 363
 364	if (!oneshot)
 365		apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
 366}
 367
 368/*
 369 * Setup extended LVT, AMD specific
 370 *
 371 * Software should use the LVT offsets the BIOS provides.  The offsets
 372 * are determined by the subsystems using it like those for MCE
 373 * threshold or IBS.  On K8 only offset 0 (APIC500) and MCE interrupts
 374 * are supported. Beginning with family 10h at least 4 offsets are
 375 * available.
 376 *
 377 * Since the offsets must be consistent for all cores, we keep track
 378 * of the LVT offsets in software and reserve the offset for the same
 379 * vector also to be used on other cores. An offset is freed by
 380 * setting the entry to APIC_EILVT_MASKED.
 381 *
 382 * If the BIOS is right, there should be no conflicts. Otherwise a
 383 * "[Firmware Bug]: ..." error message is generated. However, if
 384 * software does not properly determines the offsets, it is not
 385 * necessarily a BIOS bug.
 386 */
 387
 388static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
 389
 390static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
 391{
 392	return (old & APIC_EILVT_MASKED)
 393		|| (new == APIC_EILVT_MASKED)
 394		|| ((new & ~APIC_EILVT_MASKED) == old);
 395}
 396
 397static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
 398{
 399	unsigned int rsvd, vector;
 400
 401	if (offset >= APIC_EILVT_NR_MAX)
 402		return ~0;
 403
 404	rsvd = atomic_read(&eilvt_offsets[offset]);
 405	do {
 406		vector = rsvd & ~APIC_EILVT_MASKED;	/* 0: unassigned */
 407		if (vector && !eilvt_entry_is_changeable(vector, new))
 408			/* may not change if vectors are different */
 409			return rsvd;
 410		rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
 411	} while (rsvd != new);
 412
 413	rsvd &= ~APIC_EILVT_MASKED;
 414	if (rsvd && rsvd != vector)
 415		pr_info("LVT offset %d assigned for vector 0x%02x\n",
 416			offset, rsvd);
 417
 418	return new;
 419}
 420
 421/*
 422 * If mask=1, the LVT entry does not generate interrupts while mask=0
 423 * enables the vector. See also the BKDGs. Must be called with
 424 * preemption disabled.
 425 */
 426
 427int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
 428{
 429	unsigned long reg = APIC_EILVTn(offset);
 430	unsigned int new, old, reserved;
 431
 432	new = (mask << 16) | (msg_type << 8) | vector;
 433	old = apic_read(reg);
 434	reserved = reserve_eilvt_offset(offset, new);
 435
 436	if (reserved != new) {
 437		pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
 438		       "vector 0x%x, but the register is already in use for "
 439		       "vector 0x%x on another cpu\n",
 440		       smp_processor_id(), reg, offset, new, reserved);
 441		return -EINVAL;
 442	}
 443
 444	if (!eilvt_entry_is_changeable(old, 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 this cpu\n",
 448		       smp_processor_id(), reg, offset, new, old);
 449		return -EBUSY;
 450	}
 451
 452	apic_write(reg, new);
 453
 454	return 0;
 455}
 456EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
 457
 458/*
 459 * Program the next event, relative to now
 460 */
 461static int lapic_next_event(unsigned long delta,
 462			    struct clock_event_device *evt)
 463{
 464	apic_write(APIC_TMICT, delta);
 465	return 0;
 466}
 467
 468static int lapic_next_deadline(unsigned long delta,
 469			       struct clock_event_device *evt)
 470{
 471	u64 tsc;
 472
 473	tsc = rdtsc();
 474	wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
 475	return 0;
 476}
 477
 478static int lapic_timer_shutdown(struct clock_event_device *evt)
 479{
 
 480	unsigned int v;
 481
 482	/* Lapic used as dummy for broadcast ? */
 483	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
 484		return 0;
 485
 486	v = apic_read(APIC_LVTT);
 487	v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
 488	apic_write(APIC_LVTT, v);
 489	apic_write(APIC_TMICT, 0);
 490	return 0;
 491}
 492
 493static inline int
 494lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
 495{
 496	/* Lapic used as dummy for broadcast ? */
 497	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
 498		return 0;
 
 
 
 
 
 
 
 
 
 
 
 499
 500	__setup_APIC_LVTT(lapic_timer_frequency, oneshot, 1);
 501	return 0;
 502}
 503
 504static int lapic_timer_set_periodic(struct clock_event_device *evt)
 505{
 506	return lapic_timer_set_periodic_oneshot(evt, false);
 507}
 508
 509static int lapic_timer_set_oneshot(struct clock_event_device *evt)
 510{
 511	return lapic_timer_set_periodic_oneshot(evt, true);
 512}
 513
 514/*
 515 * Local APIC timer broadcast function
 516 */
 517static void lapic_timer_broadcast(const struct cpumask *mask)
 518{
 519#ifdef CONFIG_SMP
 520	apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
 521#endif
 522}
 523
 524
 525/*
 526 * The local apic timer can be used for any function which is CPU local.
 527 */
 528static struct clock_event_device lapic_clockevent = {
 529	.name			= "lapic",
 530	.features		= CLOCK_EVT_FEAT_PERIODIC |
 531				  CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
 532				  | CLOCK_EVT_FEAT_DUMMY,
 533	.shift			= 32,
 534	.set_state_shutdown	= lapic_timer_shutdown,
 535	.set_state_periodic	= lapic_timer_set_periodic,
 536	.set_state_oneshot	= lapic_timer_set_oneshot,
 537	.set_next_event		= lapic_next_event,
 538	.broadcast		= lapic_timer_broadcast,
 539	.rating			= 100,
 540	.irq			= -1,
 541};
 542static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
 543
 544/*
 545 * Setup the local APIC timer for this CPU. Copy the initialized values
 546 * of the boot CPU and register the clock event in the framework.
 547 */
 548static void setup_APIC_timer(void)
 549{
 550	struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
 551
 552	if (this_cpu_has(X86_FEATURE_ARAT)) {
 553		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
 554		/* Make LAPIC timer preferrable over percpu HPET */
 555		lapic_clockevent.rating = 150;
 556	}
 557
 558	memcpy(levt, &lapic_clockevent, sizeof(*levt));
 559	levt->cpumask = cpumask_of(smp_processor_id());
 560
 561	if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
 562		levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
 563				    CLOCK_EVT_FEAT_DUMMY);
 564		levt->set_next_event = lapic_next_deadline;
 565		clockevents_config_and_register(levt,
 566						(tsc_khz / TSC_DIVISOR) * 1000,
 567						0xF, ~0UL);
 568	} else
 569		clockevents_register_device(levt);
 570}
 571
 572/*
 573 * In this functions we calibrate APIC bus clocks to the external timer.
 574 *
 575 * We want to do the calibration only once since we want to have local timer
 576 * irqs syncron. CPUs connected by the same APIC bus have the very same bus
 577 * frequency.
 578 *
 579 * This was previously done by reading the PIT/HPET and waiting for a wrap
 580 * around to find out, that a tick has elapsed. I have a box, where the PIT
 581 * readout is broken, so it never gets out of the wait loop again. This was
 582 * also reported by others.
 583 *
 584 * Monitoring the jiffies value is inaccurate and the clockevents
 585 * infrastructure allows us to do a simple substitution of the interrupt
 586 * handler.
 587 *
 588 * The calibration routine also uses the pm_timer when possible, as the PIT
 589 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
 590 * back to normal later in the boot process).
 591 */
 592
 593#define LAPIC_CAL_LOOPS		(HZ/10)
 594
 595static __initdata int lapic_cal_loops = -1;
 596static __initdata long lapic_cal_t1, lapic_cal_t2;
 597static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
 598static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
 599static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
 600
 601/*
 602 * Temporary interrupt handler.
 603 */
 604static void __init lapic_cal_handler(struct clock_event_device *dev)
 605{
 606	unsigned long long tsc = 0;
 607	long tapic = apic_read(APIC_TMCCT);
 608	unsigned long pm = acpi_pm_read_early();
 609
 610	if (cpu_has_tsc)
 611		tsc = rdtsc();
 612
 613	switch (lapic_cal_loops++) {
 614	case 0:
 615		lapic_cal_t1 = tapic;
 616		lapic_cal_tsc1 = tsc;
 617		lapic_cal_pm1 = pm;
 618		lapic_cal_j1 = jiffies;
 619		break;
 620
 621	case LAPIC_CAL_LOOPS:
 622		lapic_cal_t2 = tapic;
 623		lapic_cal_tsc2 = tsc;
 624		if (pm < lapic_cal_pm1)
 625			pm += ACPI_PM_OVRRUN;
 626		lapic_cal_pm2 = pm;
 627		lapic_cal_j2 = jiffies;
 628		break;
 629	}
 630}
 631
 632static int __init
 633calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
 634{
 635	const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
 636	const long pm_thresh = pm_100ms / 100;
 637	unsigned long mult;
 638	u64 res;
 639
 640#ifndef CONFIG_X86_PM_TIMER
 641	return -1;
 642#endif
 643
 644	apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
 645
 646	/* Check, if the PM timer is available */
 647	if (!deltapm)
 648		return -1;
 649
 650	mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
 651
 652	if (deltapm > (pm_100ms - pm_thresh) &&
 653	    deltapm < (pm_100ms + pm_thresh)) {
 654		apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n");
 655		return 0;
 656	}
 657
 658	res = (((u64)deltapm) *  mult) >> 22;
 659	do_div(res, 1000000);
 660	pr_warning("APIC calibration not consistent "
 661		   "with PM-Timer: %ldms instead of 100ms\n",(long)res);
 662
 663	/* Correct the lapic counter value */
 664	res = (((u64)(*delta)) * pm_100ms);
 665	do_div(res, deltapm);
 666	pr_info("APIC delta adjusted to PM-Timer: "
 667		"%lu (%ld)\n", (unsigned long)res, *delta);
 668	*delta = (long)res;
 669
 670	/* Correct the tsc counter value */
 671	if (cpu_has_tsc) {
 672		res = (((u64)(*deltatsc)) * pm_100ms);
 673		do_div(res, deltapm);
 674		apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
 675					  "PM-Timer: %lu (%ld)\n",
 676					(unsigned long)res, *deltatsc);
 677		*deltatsc = (long)res;
 678	}
 679
 680	return 0;
 681}
 682
 683static int __init calibrate_APIC_clock(void)
 684{
 685	struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
 686	void (*real_handler)(struct clock_event_device *dev);
 687	unsigned long deltaj;
 688	long delta, deltatsc;
 689	int pm_referenced = 0;
 690
 691	/**
 692	 * check if lapic timer has already been calibrated by platform
 693	 * specific routine, such as tsc calibration code. if so, we just fill
 694	 * in the clockevent structure and return.
 695	 */
 696
 697	if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
 698		return 0;
 699	} else if (lapic_timer_frequency) {
 700		apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
 701				lapic_timer_frequency);
 702		lapic_clockevent.mult = div_sc(lapic_timer_frequency/APIC_DIVISOR,
 703					TICK_NSEC, lapic_clockevent.shift);
 704		lapic_clockevent.max_delta_ns =
 705			clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
 706		lapic_clockevent.min_delta_ns =
 707			clockevent_delta2ns(0xF, &lapic_clockevent);
 708		lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
 709		return 0;
 710	}
 711
 712	apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
 713		    "calibrating APIC timer ...\n");
 714
 715	local_irq_disable();
 716
 717	/* Replace the global interrupt handler */
 718	real_handler = global_clock_event->event_handler;
 719	global_clock_event->event_handler = lapic_cal_handler;
 720
 721	/*
 722	 * Setup the APIC counter to maximum. There is no way the lapic
 723	 * can underflow in the 100ms detection time frame
 724	 */
 725	__setup_APIC_LVTT(0xffffffff, 0, 0);
 726
 727	/* Let the interrupts run */
 728	local_irq_enable();
 729
 730	while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
 731		cpu_relax();
 732
 733	local_irq_disable();
 734
 735	/* Restore the real event handler */
 736	global_clock_event->event_handler = real_handler;
 737
 738	/* Build delta t1-t2 as apic timer counts down */
 739	delta = lapic_cal_t1 - lapic_cal_t2;
 740	apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
 741
 742	deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
 743
 744	/* we trust the PM based calibration if possible */
 745	pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
 746					&delta, &deltatsc);
 747
 748	/* Calculate the scaled math multiplication factor */
 749	lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
 750				       lapic_clockevent.shift);
 751	lapic_clockevent.max_delta_ns =
 752		clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
 753	lapic_clockevent.min_delta_ns =
 754		clockevent_delta2ns(0xF, &lapic_clockevent);
 755
 756	lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
 757
 758	apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
 759	apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
 760	apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
 761		    lapic_timer_frequency);
 762
 763	if (cpu_has_tsc) {
 764		apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
 765			    "%ld.%04ld MHz.\n",
 766			    (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
 767			    (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
 768	}
 769
 770	apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
 771		    "%u.%04u MHz.\n",
 772		    lapic_timer_frequency / (1000000 / HZ),
 773		    lapic_timer_frequency % (1000000 / HZ));
 774
 775	/*
 776	 * Do a sanity check on the APIC calibration result
 777	 */
 778	if (lapic_timer_frequency < (1000000 / HZ)) {
 779		local_irq_enable();
 780		pr_warning("APIC frequency too slow, disabling apic timer\n");
 781		return -1;
 782	}
 783
 784	levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
 785
 786	/*
 787	 * PM timer calibration failed or not turned on
 788	 * so lets try APIC timer based calibration
 789	 */
 790	if (!pm_referenced) {
 791		apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
 792
 793		/*
 794		 * Setup the apic timer manually
 795		 */
 796		levt->event_handler = lapic_cal_handler;
 797		lapic_timer_set_periodic(levt);
 798		lapic_cal_loops = -1;
 799
 800		/* Let the interrupts run */
 801		local_irq_enable();
 802
 803		while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
 804			cpu_relax();
 805
 806		/* Stop the lapic timer */
 807		local_irq_disable();
 808		lapic_timer_shutdown(levt);
 809
 810		/* Jiffies delta */
 811		deltaj = lapic_cal_j2 - lapic_cal_j1;
 812		apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
 813
 814		/* Check, if the jiffies result is consistent */
 815		if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
 816			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
 817		else
 818			levt->features |= CLOCK_EVT_FEAT_DUMMY;
 819	}
 820	local_irq_enable();
 821
 822	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
 823		pr_warning("APIC timer disabled due to verification failure\n");
 824			return -1;
 825	}
 826
 827	return 0;
 828}
 829
 830/*
 831 * Setup the boot APIC
 832 *
 833 * Calibrate and verify the result.
 834 */
 835void __init setup_boot_APIC_clock(void)
 836{
 837	/*
 838	 * The local apic timer can be disabled via the kernel
 839	 * commandline or from the CPU detection code. Register the lapic
 840	 * timer as a dummy clock event source on SMP systems, so the
 841	 * broadcast mechanism is used. On UP systems simply ignore it.
 842	 */
 843	if (disable_apic_timer) {
 844		pr_info("Disabling APIC timer\n");
 845		/* No broadcast on UP ! */
 846		if (num_possible_cpus() > 1) {
 847			lapic_clockevent.mult = 1;
 848			setup_APIC_timer();
 849		}
 850		return;
 851	}
 852
 
 
 
 853	if (calibrate_APIC_clock()) {
 854		/* No broadcast on UP ! */
 855		if (num_possible_cpus() > 1)
 856			setup_APIC_timer();
 857		return;
 858	}
 859
 860	/*
 861	 * If nmi_watchdog is set to IO_APIC, we need the
 862	 * PIT/HPET going.  Otherwise register lapic as a dummy
 863	 * device.
 864	 */
 865	lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
 866
 867	/* Setup the lapic or request the broadcast */
 868	setup_APIC_timer();
 869}
 870
 871void setup_secondary_APIC_clock(void)
 872{
 873	setup_APIC_timer();
 874}
 875
 876/*
 877 * The guts of the apic timer interrupt
 878 */
 879static void local_apic_timer_interrupt(void)
 880{
 881	int cpu = smp_processor_id();
 882	struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
 883
 884	/*
 885	 * Normally we should not be here till LAPIC has been initialized but
 886	 * in some cases like kdump, its possible that there is a pending LAPIC
 887	 * timer interrupt from previous kernel's context and is delivered in
 888	 * new kernel the moment interrupts are enabled.
 889	 *
 890	 * Interrupts are enabled early and LAPIC is setup much later, hence
 891	 * its possible that when we get here evt->event_handler is NULL.
 892	 * Check for event_handler being NULL and discard the interrupt as
 893	 * spurious.
 894	 */
 895	if (!evt->event_handler) {
 896		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
 897		/* Switch it off */
 898		lapic_timer_shutdown(evt);
 899		return;
 900	}
 901
 902	/*
 903	 * the NMI deadlock-detector uses this.
 904	 */
 905	inc_irq_stat(apic_timer_irqs);
 906
 907	evt->event_handler(evt);
 908}
 909
 910/*
 911 * Local APIC timer interrupt. This is the most natural way for doing
 912 * local interrupts, but local timer interrupts can be emulated by
 913 * broadcast interrupts too. [in case the hw doesn't support APIC timers]
 914 *
 915 * [ if a single-CPU system runs an SMP kernel then we call the local
 916 *   interrupt as well. Thus we cannot inline the local irq ... ]
 917 */
 918__visible void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs)
 919{
 920	struct pt_regs *old_regs = set_irq_regs(regs);
 921
 922	/*
 923	 * NOTE! We'd better ACK the irq immediately,
 924	 * because timer handling can be slow.
 925	 *
 926	 * update_process_times() expects us to have done irq_enter().
 927	 * Besides, if we don't timer interrupts ignore the global
 928	 * interrupt lock, which is the WrongThing (tm) to do.
 929	 */
 930	entering_ack_irq();
 931	local_apic_timer_interrupt();
 932	exiting_irq();
 933
 934	set_irq_regs(old_regs);
 935}
 936
 937__visible void __irq_entry smp_trace_apic_timer_interrupt(struct pt_regs *regs)
 938{
 939	struct pt_regs *old_regs = set_irq_regs(regs);
 940
 941	/*
 942	 * NOTE! We'd better ACK the irq immediately,
 943	 * because timer handling can be slow.
 944	 *
 945	 * update_process_times() expects us to have done irq_enter().
 946	 * Besides, if we don't timer interrupts ignore the global
 947	 * interrupt lock, which is the WrongThing (tm) to do.
 948	 */
 949	entering_ack_irq();
 950	trace_local_timer_entry(LOCAL_TIMER_VECTOR);
 951	local_apic_timer_interrupt();
 952	trace_local_timer_exit(LOCAL_TIMER_VECTOR);
 953	exiting_irq();
 954
 955	set_irq_regs(old_regs);
 956}
 957
 958int setup_profiling_timer(unsigned int multiplier)
 959{
 960	return -EINVAL;
 961}
 962
 963/*
 964 * Local APIC start and shutdown
 965 */
 966
 967/**
 968 * clear_local_APIC - shutdown the local APIC
 969 *
 970 * This is called, when a CPU is disabled and before rebooting, so the state of
 971 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
 972 * leftovers during boot.
 973 */
 974void clear_local_APIC(void)
 975{
 976	int maxlvt;
 977	u32 v;
 978
 979	/* APIC hasn't been mapped yet */
 980	if (!x2apic_mode && !apic_phys)
 981		return;
 982
 983	maxlvt = lapic_get_maxlvt();
 984	/*
 985	 * Masking an LVT entry can trigger a local APIC error
 986	 * if the vector is zero. Mask LVTERR first to prevent this.
 987	 */
 988	if (maxlvt >= 3) {
 989		v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
 990		apic_write(APIC_LVTERR, v | APIC_LVT_MASKED);
 991	}
 992	/*
 993	 * Careful: we have to set masks only first to deassert
 994	 * any level-triggered sources.
 995	 */
 996	v = apic_read(APIC_LVTT);
 997	apic_write(APIC_LVTT, v | APIC_LVT_MASKED);
 998	v = apic_read(APIC_LVT0);
 999	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
1000	v = apic_read(APIC_LVT1);
1001	apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
1002	if (maxlvt >= 4) {
1003		v = apic_read(APIC_LVTPC);
1004		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
1005	}
1006
1007	/* lets not touch this if we didn't frob it */
1008#ifdef CONFIG_X86_THERMAL_VECTOR
1009	if (maxlvt >= 5) {
1010		v = apic_read(APIC_LVTTHMR);
1011		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
1012	}
1013#endif
1014#ifdef CONFIG_X86_MCE_INTEL
1015	if (maxlvt >= 6) {
1016		v = apic_read(APIC_LVTCMCI);
1017		if (!(v & APIC_LVT_MASKED))
1018			apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
1019	}
1020#endif
1021
1022	/*
1023	 * Clean APIC state for other OSs:
1024	 */
1025	apic_write(APIC_LVTT, APIC_LVT_MASKED);
1026	apic_write(APIC_LVT0, APIC_LVT_MASKED);
1027	apic_write(APIC_LVT1, APIC_LVT_MASKED);
1028	if (maxlvt >= 3)
1029		apic_write(APIC_LVTERR, APIC_LVT_MASKED);
1030	if (maxlvt >= 4)
1031		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
1032
1033	/* Integrated APIC (!82489DX) ? */
1034	if (lapic_is_integrated()) {
1035		if (maxlvt > 3)
1036			/* Clear ESR due to Pentium errata 3AP and 11AP */
1037			apic_write(APIC_ESR, 0);
1038		apic_read(APIC_ESR);
1039	}
1040}
1041
1042/**
1043 * disable_local_APIC - clear and disable the local APIC
1044 */
1045void disable_local_APIC(void)
1046{
1047	unsigned int value;
1048
1049	/* APIC hasn't been mapped yet */
1050	if (!x2apic_mode && !apic_phys)
1051		return;
1052
1053	clear_local_APIC();
1054
1055	/*
1056	 * Disable APIC (implies clearing of registers
1057	 * for 82489DX!).
1058	 */
1059	value = apic_read(APIC_SPIV);
1060	value &= ~APIC_SPIV_APIC_ENABLED;
1061	apic_write(APIC_SPIV, value);
1062
1063#ifdef CONFIG_X86_32
1064	/*
1065	 * When LAPIC was disabled by the BIOS and enabled by the kernel,
1066	 * restore the disabled state.
1067	 */
1068	if (enabled_via_apicbase) {
1069		unsigned int l, h;
1070
1071		rdmsr(MSR_IA32_APICBASE, l, h);
1072		l &= ~MSR_IA32_APICBASE_ENABLE;
1073		wrmsr(MSR_IA32_APICBASE, l, h);
1074	}
1075#endif
1076}
1077
1078/*
1079 * If Linux enabled the LAPIC against the BIOS default disable it down before
1080 * re-entering the BIOS on shutdown.  Otherwise the BIOS may get confused and
1081 * not power-off.  Additionally clear all LVT entries before disable_local_APIC
1082 * for the case where Linux didn't enable the LAPIC.
1083 */
1084void lapic_shutdown(void)
1085{
1086	unsigned long flags;
1087
1088	if (!cpu_has_apic && !apic_from_smp_config())
1089		return;
1090
1091	local_irq_save(flags);
1092
1093#ifdef CONFIG_X86_32
1094	if (!enabled_via_apicbase)
1095		clear_local_APIC();
1096	else
1097#endif
1098		disable_local_APIC();
1099
1100
1101	local_irq_restore(flags);
1102}
1103
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1104/**
1105 * sync_Arb_IDs - synchronize APIC bus arbitration IDs
1106 */
1107void __init sync_Arb_IDs(void)
1108{
1109	/*
1110	 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
1111	 * needed on AMD.
1112	 */
1113	if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1114		return;
1115
1116	/*
1117	 * Wait for idle.
1118	 */
1119	apic_wait_icr_idle();
1120
1121	apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
1122	apic_write(APIC_ICR, APIC_DEST_ALLINC |
1123			APIC_INT_LEVELTRIG | APIC_DM_INIT);
1124}
1125
1126/*
1127 * An initial setup of the virtual wire mode.
1128 */
1129void __init init_bsp_APIC(void)
1130{
1131	unsigned int value;
1132
1133	/*
1134	 * Don't do the setup now if we have a SMP BIOS as the
1135	 * through-I/O-APIC virtual wire mode might be active.
1136	 */
1137	if (smp_found_config || !cpu_has_apic)
1138		return;
1139
1140	/*
1141	 * Do not trust the local APIC being empty at bootup.
1142	 */
1143	clear_local_APIC();
1144
1145	/*
1146	 * Enable APIC.
1147	 */
1148	value = apic_read(APIC_SPIV);
1149	value &= ~APIC_VECTOR_MASK;
1150	value |= APIC_SPIV_APIC_ENABLED;
1151
1152#ifdef CONFIG_X86_32
1153	/* This bit is reserved on P4/Xeon and should be cleared */
1154	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
1155	    (boot_cpu_data.x86 == 15))
1156		value &= ~APIC_SPIV_FOCUS_DISABLED;
1157	else
1158#endif
1159		value |= APIC_SPIV_FOCUS_DISABLED;
1160	value |= SPURIOUS_APIC_VECTOR;
1161	apic_write(APIC_SPIV, value);
1162
1163	/*
1164	 * Set up the virtual wire mode.
1165	 */
1166	apic_write(APIC_LVT0, APIC_DM_EXTINT);
1167	value = APIC_DM_NMI;
1168	if (!lapic_is_integrated())		/* 82489DX */
1169		value |= APIC_LVT_LEVEL_TRIGGER;
1170	if (apic_extnmi == APIC_EXTNMI_NONE)
1171		value |= APIC_LVT_MASKED;
1172	apic_write(APIC_LVT1, value);
1173}
1174
1175static void lapic_setup_esr(void)
1176{
1177	unsigned int oldvalue, value, maxlvt;
1178
1179	if (!lapic_is_integrated()) {
1180		pr_info("No ESR for 82489DX.\n");
1181		return;
1182	}
1183
1184	if (apic->disable_esr) {
1185		/*
1186		 * Something untraceable is creating bad interrupts on
1187		 * secondary quads ... for the moment, just leave the
1188		 * ESR disabled - we can't do anything useful with the
1189		 * errors anyway - mbligh
1190		 */
1191		pr_info("Leaving ESR disabled.\n");
1192		return;
1193	}
1194
1195	maxlvt = lapic_get_maxlvt();
1196	if (maxlvt > 3)		/* Due to the Pentium erratum 3AP. */
1197		apic_write(APIC_ESR, 0);
1198	oldvalue = apic_read(APIC_ESR);
1199
1200	/* enables sending errors */
1201	value = ERROR_APIC_VECTOR;
1202	apic_write(APIC_LVTERR, value);
1203
1204	/*
1205	 * spec says clear errors after enabling vector.
1206	 */
1207	if (maxlvt > 3)
1208		apic_write(APIC_ESR, 0);
1209	value = apic_read(APIC_ESR);
1210	if (value != oldvalue)
1211		apic_printk(APIC_VERBOSE, "ESR value before enabling "
1212			"vector: 0x%08x  after: 0x%08x\n",
1213			oldvalue, value);
1214}
1215
1216/**
1217 * setup_local_APIC - setup the local APIC
1218 *
1219 * Used to setup local APIC while initializing BSP or bringin up APs.
1220 * Always called with preemption disabled.
1221 */
1222void setup_local_APIC(void)
1223{
1224	int cpu = smp_processor_id();
1225	unsigned int value, queued;
1226	int i, j, acked = 0;
1227	unsigned long long tsc = 0, ntsc;
1228	long long max_loops = cpu_khz ? cpu_khz : 1000000;
1229
1230	if (cpu_has_tsc)
1231		tsc = rdtsc();
1232
1233	if (disable_apic) {
1234		disable_ioapic_support();
1235		return;
1236	}
1237
1238#ifdef CONFIG_X86_32
1239	/* Pound the ESR really hard over the head with a big hammer - mbligh */
1240	if (lapic_is_integrated() && apic->disable_esr) {
1241		apic_write(APIC_ESR, 0);
1242		apic_write(APIC_ESR, 0);
1243		apic_write(APIC_ESR, 0);
1244		apic_write(APIC_ESR, 0);
1245	}
1246#endif
1247	perf_events_lapic_init();
1248
1249	/*
1250	 * Double-check whether this APIC is really registered.
1251	 * This is meaningless in clustered apic mode, so we skip it.
1252	 */
1253	BUG_ON(!apic->apic_id_registered());
1254
1255	/*
1256	 * Intel recommends to set DFR, LDR and TPR before enabling
1257	 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
1258	 * document number 292116).  So here it goes...
1259	 */
1260	apic->init_apic_ldr();
1261
1262#ifdef CONFIG_X86_32
1263	/*
1264	 * APIC LDR is initialized.  If logical_apicid mapping was
1265	 * initialized during get_smp_config(), make sure it matches the
1266	 * actual value.
1267	 */
1268	i = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
1269	WARN_ON(i != BAD_APICID && i != logical_smp_processor_id());
1270	/* always use the value from LDR */
1271	early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
1272		logical_smp_processor_id();
 
 
 
 
 
 
 
 
 
 
 
1273#endif
1274
1275	/*
1276	 * Set Task Priority to 'accept all'. We never change this
1277	 * later on.
1278	 */
1279	value = apic_read(APIC_TASKPRI);
1280	value &= ~APIC_TPRI_MASK;
1281	apic_write(APIC_TASKPRI, value);
1282
1283	/*
1284	 * After a crash, we no longer service the interrupts and a pending
1285	 * interrupt from previous kernel might still have ISR bit set.
1286	 *
1287	 * Most probably by now CPU has serviced that pending interrupt and
1288	 * it might not have done the ack_APIC_irq() because it thought,
1289	 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
1290	 * does not clear the ISR bit and cpu thinks it has already serivced
1291	 * the interrupt. Hence a vector might get locked. It was noticed
1292	 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
1293	 */
1294	do {
1295		queued = 0;
1296		for (i = APIC_ISR_NR - 1; i >= 0; i--)
1297			queued |= apic_read(APIC_IRR + i*0x10);
1298
1299		for (i = APIC_ISR_NR - 1; i >= 0; i--) {
1300			value = apic_read(APIC_ISR + i*0x10);
1301			for (j = 31; j >= 0; j--) {
1302				if (value & (1<<j)) {
1303					ack_APIC_irq();
1304					acked++;
1305				}
1306			}
1307		}
1308		if (acked > 256) {
1309			printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n",
1310			       acked);
1311			break;
1312		}
1313		if (queued) {
1314			if (cpu_has_tsc && cpu_khz) {
1315				ntsc = rdtsc();
1316				max_loops = (cpu_khz << 10) - (ntsc - tsc);
1317			} else
1318				max_loops--;
1319		}
1320	} while (queued && max_loops > 0);
1321	WARN_ON(max_loops <= 0);
1322
1323	/*
1324	 * Now that we are all set up, enable the APIC
1325	 */
1326	value = apic_read(APIC_SPIV);
1327	value &= ~APIC_VECTOR_MASK;
1328	/*
1329	 * Enable APIC
1330	 */
1331	value |= APIC_SPIV_APIC_ENABLED;
1332
1333#ifdef CONFIG_X86_32
1334	/*
1335	 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
1336	 * certain networking cards. If high frequency interrupts are
1337	 * happening on a particular IOAPIC pin, plus the IOAPIC routing
1338	 * entry is masked/unmasked at a high rate as well then sooner or
1339	 * later IOAPIC line gets 'stuck', no more interrupts are received
1340	 * from the device. If focus CPU is disabled then the hang goes
1341	 * away, oh well :-(
1342	 *
1343	 * [ This bug can be reproduced easily with a level-triggered
1344	 *   PCI Ne2000 networking cards and PII/PIII processors, dual
1345	 *   BX chipset. ]
1346	 */
1347	/*
1348	 * Actually disabling the focus CPU check just makes the hang less
1349	 * frequent as it makes the interrupt distributon model be more
1350	 * like LRU than MRU (the short-term load is more even across CPUs).
1351	 * See also the comment in end_level_ioapic_irq().  --macro
1352	 */
1353
1354	/*
1355	 * - enable focus processor (bit==0)
1356	 * - 64bit mode always use processor focus
1357	 *   so no need to set it
1358	 */
1359	value &= ~APIC_SPIV_FOCUS_DISABLED;
1360#endif
1361
1362	/*
1363	 * Set spurious IRQ vector
1364	 */
1365	value |= SPURIOUS_APIC_VECTOR;
1366	apic_write(APIC_SPIV, value);
1367
1368	/*
1369	 * Set up LVT0, LVT1:
1370	 *
1371	 * set up through-local-APIC on the BP's LINT0. This is not
1372	 * strictly necessary in pure symmetric-IO mode, but sometimes
1373	 * we delegate interrupts to the 8259A.
1374	 */
1375	/*
1376	 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
1377	 */
1378	value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
1379	if (!cpu && (pic_mode || !value)) {
1380		value = APIC_DM_EXTINT;
1381		apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
1382	} else {
1383		value = APIC_DM_EXTINT | APIC_LVT_MASKED;
1384		apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
1385	}
1386	apic_write(APIC_LVT0, value);
1387
1388	/*
1389	 * Only the BSP sees the LINT1 NMI signal by default. This can be
1390	 * modified by apic_extnmi= boot option.
1391	 */
1392	if ((!cpu && apic_extnmi != APIC_EXTNMI_NONE) ||
1393	    apic_extnmi == APIC_EXTNMI_ALL)
1394		value = APIC_DM_NMI;
1395	else
1396		value = APIC_DM_NMI | APIC_LVT_MASKED;
1397	if (!lapic_is_integrated())		/* 82489DX */
1398		value |= APIC_LVT_LEVEL_TRIGGER;
1399	apic_write(APIC_LVT1, value);
1400
1401#ifdef CONFIG_X86_MCE_INTEL
1402	/* Recheck CMCI information after local APIC is up on CPU #0 */
1403	if (!cpu)
1404		cmci_recheck();
1405#endif
1406}
1407
1408static void end_local_APIC_setup(void)
1409{
1410	lapic_setup_esr();
1411
1412#ifdef CONFIG_X86_32
1413	{
1414		unsigned int value;
1415		/* Disable the local apic timer */
1416		value = apic_read(APIC_LVTT);
1417		value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
1418		apic_write(APIC_LVTT, value);
1419	}
1420#endif
1421
1422	apic_pm_activate();
1423}
1424
1425/*
1426 * APIC setup function for application processors. Called from smpboot.c
1427 */
1428void apic_ap_setup(void)
1429{
1430	setup_local_APIC();
1431	end_local_APIC_setup();
 
 
 
 
 
 
 
 
1432}
1433
1434#ifdef CONFIG_X86_X2APIC
1435int x2apic_mode;
1436
1437enum {
1438	X2APIC_OFF,
1439	X2APIC_ON,
1440	X2APIC_DISABLED,
1441};
1442static int x2apic_state;
 
1443
1444static void __x2apic_disable(void)
1445{
1446	u64 msr;
1447
1448	if (!cpu_has_apic)
1449		return;
1450
1451	rdmsrl(MSR_IA32_APICBASE, msr);
1452	if (!(msr & X2APIC_ENABLE))
1453		return;
1454	/* Disable xapic and x2apic first and then reenable xapic mode */
1455	wrmsrl(MSR_IA32_APICBASE, msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
1456	wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
1457	printk_once(KERN_INFO "x2apic disabled\n");
1458}
1459
1460static void __x2apic_enable(void)
1461{
1462	u64 msr;
1463
1464	rdmsrl(MSR_IA32_APICBASE, msr);
1465	if (msr & X2APIC_ENABLE)
1466		return;
1467	wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
1468	printk_once(KERN_INFO "x2apic enabled\n");
1469}
1470
1471static int __init setup_nox2apic(char *str)
1472{
1473	if (x2apic_enabled()) {
1474		int apicid = native_apic_msr_read(APIC_ID);
1475
1476		if (apicid >= 255) {
1477			pr_warning("Apicid: %08x, cannot enforce nox2apic\n",
1478				   apicid);
1479			return 0;
1480		}
1481		pr_warning("x2apic already enabled.\n");
1482		__x2apic_disable();
1483	}
1484	setup_clear_cpu_cap(X86_FEATURE_X2APIC);
1485	x2apic_state = X2APIC_DISABLED;
1486	x2apic_mode = 0;
1487	return 0;
1488}
1489early_param("nox2apic", setup_nox2apic);
1490
1491/* Called from cpu_init() to enable x2apic on (secondary) cpus */
1492void x2apic_setup(void)
1493{
1494	/*
1495	 * If x2apic is not in ON state, disable it if already enabled
1496	 * from BIOS.
1497	 */
1498	if (x2apic_state != X2APIC_ON) {
1499		__x2apic_disable();
1500		return;
1501	}
1502	__x2apic_enable();
1503}
1504
1505static __init void x2apic_disable(void)
1506{
1507	u32 x2apic_id, state = x2apic_state;
1508
1509	x2apic_mode = 0;
1510	x2apic_state = X2APIC_DISABLED;
1511
1512	if (state != X2APIC_ON)
1513		return;
 
1514
1515	x2apic_id = read_apic_id();
1516	if (x2apic_id >= 255)
1517		panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
1518
1519	__x2apic_disable();
1520	register_lapic_address(mp_lapic_addr);
1521}
1522
1523static __init void x2apic_enable(void)
1524{
1525	if (x2apic_state != X2APIC_OFF)
1526		return;
1527
1528	x2apic_mode = 1;
1529	x2apic_state = X2APIC_ON;
1530	__x2apic_enable();
1531}
1532
1533static __init void try_to_enable_x2apic(int remap_mode)
1534{
1535	if (x2apic_state == X2APIC_DISABLED)
1536		return;
1537
1538	if (remap_mode != IRQ_REMAP_X2APIC_MODE) {
1539		/* IR is required if there is APIC ID > 255 even when running
1540		 * under KVM
1541		 */
1542		if (max_physical_apicid > 255 ||
1543		    !hypervisor_x2apic_available()) {
1544			pr_info("x2apic: IRQ remapping doesn't support X2APIC mode\n");
1545			x2apic_disable();
1546			return;
1547		}
1548
1549		/*
1550		 * without IR all CPUs can be addressed by IOAPIC/MSI
1551		 * only in physical mode
1552		 */
1553		x2apic_phys = 1;
1554	}
1555	x2apic_enable();
1556}
 
1557
1558void __init check_x2apic(void)
1559{
1560	if (x2apic_enabled()) {
1561		pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");
1562		x2apic_mode = 1;
1563		x2apic_state = X2APIC_ON;
1564	} else if (!cpu_has_x2apic) {
1565		x2apic_state = X2APIC_DISABLED;
1566	}
1567}
1568#else /* CONFIG_X86_X2APIC */
1569static int __init validate_x2apic(void)
1570{
1571	if (!apic_is_x2apic_enabled())
1572		return 0;
1573	/*
1574	 * Checkme: Can we simply turn off x2apic here instead of panic?
1575	 */
1576	panic("BIOS has enabled x2apic but kernel doesn't support x2apic, please disable x2apic in BIOS.\n");
1577}
1578early_initcall(validate_x2apic);
1579
1580static inline void try_to_enable_x2apic(int remap_mode) { }
1581static inline void __x2apic_enable(void) { }
1582#endif /* !CONFIG_X86_X2APIC */
1583
1584static int __init try_to_enable_IR(void)
1585{
1586#ifdef CONFIG_X86_IO_APIC
1587	if (!x2apic_enabled() && skip_ioapic_setup) {
1588		pr_info("Not enabling interrupt remapping due to skipped IO-APIC setup\n");
1589		return -1;
1590	}
 
 
1591#endif
1592	return irq_remapping_enable();
1593}
1594
1595void __init enable_IR_x2apic(void)
1596{
1597	unsigned long flags;
1598	int ret, ir_stat;
 
 
 
 
1599
1600	ir_stat = irq_remapping_prepare();
1601	if (ir_stat < 0 && !x2apic_supported())
1602		return;
1603
1604	ret = save_ioapic_entries();
1605	if (ret) {
1606		pr_info("Saving IO-APIC state failed: %d\n", ret);
1607		return;
1608	}
1609
1610	local_irq_save(flags);
1611	legacy_pic->mask_all();
1612	mask_ioapic_entries();
1613
1614	/* If irq_remapping_prepare() succeeded, try to enable it */
1615	if (ir_stat >= 0)
1616		ir_stat = try_to_enable_IR();
1617	/* ir_stat contains the remap mode or an error code */
1618	try_to_enable_x2apic(ir_stat);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1619
1620	if (ir_stat < 0)
 
 
 
 
 
 
 
 
 
1621		restore_ioapic_entries();
1622	legacy_pic->restore_mask();
1623	local_irq_restore(flags);
1624}
1625
1626#ifdef CONFIG_X86_64
1627/*
1628 * Detect and enable local APICs on non-SMP boards.
1629 * Original code written by Keir Fraser.
1630 * On AMD64 we trust the BIOS - if it says no APIC it is likely
1631 * not correctly set up (usually the APIC timer won't work etc.)
1632 */
1633static int __init detect_init_APIC(void)
1634{
1635	if (!cpu_has_apic) {
1636		pr_info("No local APIC present\n");
1637		return -1;
1638	}
1639
1640	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1641	return 0;
1642}
1643#else
1644
1645static int __init apic_verify(void)
1646{
1647	u32 features, h, l;
1648
1649	/*
1650	 * The APIC feature bit should now be enabled
1651	 * in `cpuid'
1652	 */
1653	features = cpuid_edx(1);
1654	if (!(features & (1 << X86_FEATURE_APIC))) {
1655		pr_warning("Could not enable APIC!\n");
1656		return -1;
1657	}
1658	set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
1659	mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
1660
1661	/* The BIOS may have set up the APIC at some other address */
1662	if (boot_cpu_data.x86 >= 6) {
1663		rdmsr(MSR_IA32_APICBASE, l, h);
1664		if (l & MSR_IA32_APICBASE_ENABLE)
1665			mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
1666	}
1667
1668	pr_info("Found and enabled local APIC!\n");
1669	return 0;
1670}
1671
1672int __init apic_force_enable(unsigned long addr)
1673{
1674	u32 h, l;
1675
1676	if (disable_apic)
1677		return -1;
1678
1679	/*
1680	 * Some BIOSes disable the local APIC in the APIC_BASE
1681	 * MSR. This can only be done in software for Intel P6 or later
1682	 * and AMD K7 (Model > 1) or later.
1683	 */
1684	if (boot_cpu_data.x86 >= 6) {
1685		rdmsr(MSR_IA32_APICBASE, l, h);
1686		if (!(l & MSR_IA32_APICBASE_ENABLE)) {
1687			pr_info("Local APIC disabled by BIOS -- reenabling.\n");
1688			l &= ~MSR_IA32_APICBASE_BASE;
1689			l |= MSR_IA32_APICBASE_ENABLE | addr;
1690			wrmsr(MSR_IA32_APICBASE, l, h);
1691			enabled_via_apicbase = 1;
1692		}
1693	}
1694	return apic_verify();
1695}
1696
1697/*
1698 * Detect and initialize APIC
1699 */
1700static int __init detect_init_APIC(void)
1701{
1702	/* Disabled by kernel option? */
1703	if (disable_apic)
1704		return -1;
1705
1706	switch (boot_cpu_data.x86_vendor) {
1707	case X86_VENDOR_AMD:
1708		if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
1709		    (boot_cpu_data.x86 >= 15))
1710			break;
1711		goto no_apic;
1712	case X86_VENDOR_INTEL:
1713		if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
1714		    (boot_cpu_data.x86 == 5 && cpu_has_apic))
1715			break;
1716		goto no_apic;
1717	default:
1718		goto no_apic;
1719	}
1720
1721	if (!cpu_has_apic) {
1722		/*
1723		 * Over-ride BIOS and try to enable the local APIC only if
1724		 * "lapic" specified.
1725		 */
1726		if (!force_enable_local_apic) {
1727			pr_info("Local APIC disabled by BIOS -- "
1728				"you can enable it with \"lapic\"\n");
1729			return -1;
1730		}
1731		if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
1732			return -1;
1733	} else {
1734		if (apic_verify())
1735			return -1;
1736	}
1737
1738	apic_pm_activate();
1739
1740	return 0;
1741
1742no_apic:
1743	pr_info("No local APIC present or hardware disabled\n");
1744	return -1;
1745}
1746#endif
1747
1748/**
1749 * init_apic_mappings - initialize APIC mappings
1750 */
1751void __init init_apic_mappings(void)
1752{
1753	unsigned int new_apicid;
1754
1755	if (x2apic_mode) {
1756		boot_cpu_physical_apicid = read_apic_id();
1757		return;
1758	}
1759
1760	/* If no local APIC can be found return early */
1761	if (!smp_found_config && detect_init_APIC()) {
1762		/* lets NOP'ify apic operations */
1763		pr_info("APIC: disable apic facility\n");
1764		apic_disable();
1765	} else {
1766		apic_phys = mp_lapic_addr;
1767
1768		/*
1769		 * acpi lapic path already maps that address in
1770		 * acpi_register_lapic_address()
1771		 */
1772		if (!acpi_lapic && !smp_found_config)
1773			register_lapic_address(apic_phys);
1774	}
1775
1776	/*
1777	 * Fetch the APIC ID of the BSP in case we have a
1778	 * default configuration (or the MP table is broken).
1779	 */
1780	new_apicid = read_apic_id();
1781	if (boot_cpu_physical_apicid != new_apicid) {
1782		boot_cpu_physical_apicid = new_apicid;
1783		/*
1784		 * yeah -- we lie about apic_version
1785		 * in case if apic was disabled via boot option
1786		 * but it's not a problem for SMP compiled kernel
1787		 * since smp_sanity_check is prepared for such a case
1788		 * and disable smp mode
1789		 */
1790		apic_version[new_apicid] =
1791			 GET_APIC_VERSION(apic_read(APIC_LVR));
1792	}
1793}
1794
1795void __init register_lapic_address(unsigned long address)
1796{
1797	mp_lapic_addr = address;
1798
1799	if (!x2apic_mode) {
1800		set_fixmap_nocache(FIX_APIC_BASE, address);
1801		apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
1802			    APIC_BASE, mp_lapic_addr);
1803	}
1804	if (boot_cpu_physical_apicid == -1U) {
1805		boot_cpu_physical_apicid  = read_apic_id();
1806		apic_version[boot_cpu_physical_apicid] =
1807			 GET_APIC_VERSION(apic_read(APIC_LVR));
1808	}
1809}
1810
 
 
 
 
1811int apic_version[MAX_LOCAL_APIC];
1812
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1813/*
1814 * Local APIC interrupts
1815 */
1816
1817/*
1818 * This interrupt should _never_ happen with our APIC/SMP architecture
1819 */
1820static void __smp_spurious_interrupt(u8 vector)
1821{
1822	u32 v;
1823
 
 
1824	/*
1825	 * Check if this really is a spurious interrupt and ACK it
1826	 * if it is a vectored one.  Just in case...
1827	 * Spurious interrupts should not be ACKed.
1828	 */
1829	v = apic_read(APIC_ISR + ((vector & ~0x1f) >> 1));
1830	if (v & (1 << (vector & 0x1f)))
1831		ack_APIC_irq();
1832
1833	inc_irq_stat(irq_spurious_count);
1834
1835	/* see sw-dev-man vol 3, chapter 7.4.13.5 */
1836	pr_info("spurious APIC interrupt through vector %02x on CPU#%d, "
1837		"should never happen.\n", vector, smp_processor_id());
1838}
1839
1840__visible void smp_spurious_interrupt(struct pt_regs *regs)
1841{
1842	entering_irq();
1843	__smp_spurious_interrupt(~regs->orig_ax);
1844	exiting_irq();
1845}
1846
1847__visible void smp_trace_spurious_interrupt(struct pt_regs *regs)
1848{
1849	u8 vector = ~regs->orig_ax;
1850
1851	entering_irq();
1852	trace_spurious_apic_entry(vector);
1853	__smp_spurious_interrupt(vector);
1854	trace_spurious_apic_exit(vector);
1855	exiting_irq();
1856}
1857
1858/*
1859 * This interrupt should never happen with our APIC/SMP architecture
1860 */
1861static void __smp_error_interrupt(struct pt_regs *regs)
1862{
1863	u32 v;
1864	u32 i = 0;
1865	static const char * const error_interrupt_reason[] = {
1866		"Send CS error",		/* APIC Error Bit 0 */
1867		"Receive CS error",		/* APIC Error Bit 1 */
1868		"Send accept error",		/* APIC Error Bit 2 */
1869		"Receive accept error",		/* APIC Error Bit 3 */
1870		"Redirectable IPI",		/* APIC Error Bit 4 */
1871		"Send illegal vector",		/* APIC Error Bit 5 */
1872		"Received illegal vector",	/* APIC Error Bit 6 */
1873		"Illegal register address",	/* APIC Error Bit 7 */
1874	};
1875
 
 
1876	/* First tickle the hardware, only then report what went on. -- REW */
1877	if (lapic_get_maxlvt() > 3)	/* Due to the Pentium erratum 3AP. */
1878		apic_write(APIC_ESR, 0);
1879	v = apic_read(APIC_ESR);
1880	ack_APIC_irq();
1881	atomic_inc(&irq_err_count);
1882
1883	apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
1884		    smp_processor_id(), v);
1885
1886	v &= 0xff;
1887	while (v) {
1888		if (v & 0x1)
1889			apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
1890		i++;
1891		v >>= 1;
1892	}
1893
1894	apic_printk(APIC_DEBUG, KERN_CONT "\n");
1895
1896}
1897
1898__visible void smp_error_interrupt(struct pt_regs *regs)
1899{
1900	entering_irq();
1901	__smp_error_interrupt(regs);
1902	exiting_irq();
1903}
1904
1905__visible void smp_trace_error_interrupt(struct pt_regs *regs)
1906{
1907	entering_irq();
1908	trace_error_apic_entry(ERROR_APIC_VECTOR);
1909	__smp_error_interrupt(regs);
1910	trace_error_apic_exit(ERROR_APIC_VECTOR);
1911	exiting_irq();
1912}
1913
1914/**
1915 * connect_bsp_APIC - attach the APIC to the interrupt system
1916 */
1917static void __init connect_bsp_APIC(void)
1918{
1919#ifdef CONFIG_X86_32
1920	if (pic_mode) {
1921		/*
1922		 * Do not trust the local APIC being empty at bootup.
1923		 */
1924		clear_local_APIC();
1925		/*
1926		 * PIC mode, enable APIC mode in the IMCR, i.e.  connect BSP's
1927		 * local APIC to INT and NMI lines.
1928		 */
1929		apic_printk(APIC_VERBOSE, "leaving PIC mode, "
1930				"enabling APIC mode.\n");
1931		imcr_pic_to_apic();
1932	}
1933#endif
 
 
1934}
1935
1936/**
1937 * disconnect_bsp_APIC - detach the APIC from the interrupt system
1938 * @virt_wire_setup:	indicates, whether virtual wire mode is selected
1939 *
1940 * Virtual wire mode is necessary to deliver legacy interrupts even when the
1941 * APIC is disabled.
1942 */
1943void disconnect_bsp_APIC(int virt_wire_setup)
1944{
1945	unsigned int value;
1946
1947#ifdef CONFIG_X86_32
1948	if (pic_mode) {
1949		/*
1950		 * Put the board back into PIC mode (has an effect only on
1951		 * certain older boards).  Note that APIC interrupts, including
1952		 * IPIs, won't work beyond this point!  The only exception are
1953		 * INIT IPIs.
1954		 */
1955		apic_printk(APIC_VERBOSE, "disabling APIC mode, "
1956				"entering PIC mode.\n");
1957		imcr_apic_to_pic();
1958		return;
1959	}
1960#endif
1961
1962	/* Go back to Virtual Wire compatibility mode */
1963
1964	/* For the spurious interrupt use vector F, and enable it */
1965	value = apic_read(APIC_SPIV);
1966	value &= ~APIC_VECTOR_MASK;
1967	value |= APIC_SPIV_APIC_ENABLED;
1968	value |= 0xf;
1969	apic_write(APIC_SPIV, value);
1970
1971	if (!virt_wire_setup) {
1972		/*
1973		 * For LVT0 make it edge triggered, active high,
1974		 * external and enabled
1975		 */
1976		value = apic_read(APIC_LVT0);
1977		value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1978			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1979			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1980		value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1981		value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
1982		apic_write(APIC_LVT0, value);
1983	} else {
1984		/* Disable LVT0 */
1985		apic_write(APIC_LVT0, APIC_LVT_MASKED);
1986	}
1987
1988	/*
1989	 * For LVT1 make it edge triggered, active high,
1990	 * nmi and enabled
1991	 */
1992	value = apic_read(APIC_LVT1);
1993	value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
1994			APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
1995			APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
1996	value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
1997	value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
1998	apic_write(APIC_LVT1, value);
1999}
2000
2001int generic_processor_info(int apicid, int version)
2002{
2003	int cpu, max = nr_cpu_ids;
2004	bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
2005				phys_cpu_present_map);
2006
2007	/*
2008	 * boot_cpu_physical_apicid is designed to have the apicid
2009	 * returned by read_apic_id(), i.e, the apicid of the
2010	 * currently booting-up processor. However, on some platforms,
2011	 * it is temporarily modified by the apicid reported as BSP
2012	 * through MP table. Concretely:
2013	 *
2014	 * - arch/x86/kernel/mpparse.c: MP_processor_info()
2015	 * - arch/x86/mm/amdtopology.c: amd_numa_init()
2016	 *
2017	 * This function is executed with the modified
2018	 * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel
2019	 * parameter doesn't work to disable APs on kdump 2nd kernel.
2020	 *
2021	 * Since fixing handling of boot_cpu_physical_apicid requires
2022	 * another discussion and tests on each platform, we leave it
2023	 * for now and here we use read_apic_id() directly in this
2024	 * function, generic_processor_info().
2025	 */
2026	if (disabled_cpu_apicid != BAD_APICID &&
2027	    disabled_cpu_apicid != read_apic_id() &&
2028	    disabled_cpu_apicid == apicid) {
2029		int thiscpu = num_processors + disabled_cpus;
2030
2031		pr_warning("APIC: Disabling requested cpu."
2032			   " Processor %d/0x%x ignored.\n",
2033			   thiscpu, apicid);
2034
2035		disabled_cpus++;
2036		return -ENODEV;
2037	}
2038
2039	/*
2040	 * If boot cpu has not been detected yet, then only allow upto
2041	 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu
2042	 */
2043	if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
2044	    apicid != boot_cpu_physical_apicid) {
2045		int thiscpu = max + disabled_cpus - 1;
2046
2047		pr_warning(
2048			"ACPI: NR_CPUS/possible_cpus limit of %i almost"
2049			" reached. Keeping one slot for boot cpu."
2050			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2051
2052		disabled_cpus++;
2053		return -ENODEV;
2054	}
2055
2056	if (num_processors >= nr_cpu_ids) {
2057		int thiscpu = max + disabled_cpus;
2058
2059		pr_warning(
2060			"ACPI: NR_CPUS/possible_cpus limit of %i reached."
2061			"  Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
2062
2063		disabled_cpus++;
2064		return -EINVAL;
2065	}
2066
2067	num_processors++;
2068	if (apicid == boot_cpu_physical_apicid) {
2069		/*
2070		 * x86_bios_cpu_apicid is required to have processors listed
2071		 * in same order as logical cpu numbers. Hence the first
2072		 * entry is BSP, and so on.
2073		 * boot_cpu_init() already hold bit 0 in cpu_present_mask
2074		 * for BSP.
2075		 */
2076		cpu = 0;
2077	} else
2078		cpu = cpumask_next_zero(-1, cpu_present_mask);
2079
2080	/*
2081	 * This can happen on physical hotplug. The sanity check at boot time
2082	 * is done from native_smp_prepare_cpus() after num_possible_cpus() is
2083	 * established.
2084	 */
2085	if (topology_update_package_map(apicid, cpu) < 0) {
2086		int thiscpu = max + disabled_cpus;
2087
2088		pr_warning("ACPI: Package limit reached. Processor %d/0x%x ignored.\n",
2089			   thiscpu, apicid);
2090		disabled_cpus++;
2091		return -ENOSPC;
2092	}
2093
2094	/*
2095	 * Validate version
2096	 */
2097	if (version == 0x0) {
2098		pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
2099			   cpu, apicid);
2100		version = 0x10;
2101	}
2102	apic_version[apicid] = version;
2103
2104	if (version != apic_version[boot_cpu_physical_apicid]) {
2105		pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
2106			apic_version[boot_cpu_physical_apicid], cpu, version);
2107	}
2108
2109	physid_set(apicid, phys_cpu_present_map);
2110	if (apicid > max_physical_apicid)
2111		max_physical_apicid = apicid;
2112
2113#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
2114	early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
2115	early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
2116#endif
2117#ifdef CONFIG_X86_32
2118	early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
2119		apic->x86_32_early_logical_apicid(cpu);
2120#endif
2121	set_cpu_possible(cpu, true);
2122	set_cpu_present(cpu, true);
2123
2124	return cpu;
2125}
2126
2127int hard_smp_processor_id(void)
2128{
2129	return read_apic_id();
2130}
2131
2132void default_init_apic_ldr(void)
2133{
2134	unsigned long val;
2135
2136	apic_write(APIC_DFR, APIC_DFR_VALUE);
2137	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
2138	val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
2139	apic_write(APIC_LDR, val);
2140}
2141
2142int default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
2143				   const struct cpumask *andmask,
2144				   unsigned int *apicid)
2145{
2146	unsigned int cpu;
2147
2148	for_each_cpu_and(cpu, cpumask, andmask) {
2149		if (cpumask_test_cpu(cpu, cpu_online_mask))
2150			break;
2151	}
2152
2153	if (likely(cpu < nr_cpu_ids)) {
2154		*apicid = per_cpu(x86_cpu_to_apicid, cpu);
2155		return 0;
2156	}
2157
2158	return -EINVAL;
2159}
2160
2161/*
2162 * Override the generic EOI implementation with an optimized version.
2163 * Only called during early boot when only one CPU is active and with
2164 * interrupts disabled, so we know this does not race with actual APIC driver
2165 * use.
2166 */
2167void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
2168{
2169	struct apic **drv;
2170
2171	for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
2172		/* Should happen once for each apic */
2173		WARN_ON((*drv)->eoi_write == eoi_write);
2174		(*drv)->eoi_write = eoi_write;
2175	}
2176}
2177
2178static void __init apic_bsp_up_setup(void)
2179{
2180#ifdef CONFIG_X86_64
2181	apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
2182#else
2183	/*
2184	 * Hack: In case of kdump, after a crash, kernel might be booting
2185	 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
2186	 * might be zero if read from MP tables. Get it from LAPIC.
2187	 */
2188# ifdef CONFIG_CRASH_DUMP
2189	boot_cpu_physical_apicid = read_apic_id();
2190# endif
2191#endif
2192	physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
2193}
2194
2195/**
2196 * apic_bsp_setup - Setup function for local apic and io-apic
2197 * @upmode:		Force UP mode (for APIC_init_uniprocessor)
2198 *
2199 * Returns:
2200 * apic_id of BSP APIC
2201 */
2202int __init apic_bsp_setup(bool upmode)
2203{
2204	int id;
2205
2206	connect_bsp_APIC();
2207	if (upmode)
2208		apic_bsp_up_setup();
2209	setup_local_APIC();
2210
2211	if (x2apic_mode)
2212		id = apic_read(APIC_LDR);
2213	else
2214		id = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
2215
2216	enable_IO_APIC();
2217	end_local_APIC_setup();
2218	irq_remap_enable_fault_handling();
2219	setup_IO_APIC();
2220	/* Setup local timer */
2221	x86_init.timers.setup_percpu_clockev();
2222	return id;
2223}
2224
2225/*
2226 * This initializes the IO-APIC and APIC hardware if this is
2227 * a UP kernel.
2228 */
2229int __init APIC_init_uniprocessor(void)
2230{
2231	if (disable_apic) {
2232		pr_info("Apic disabled\n");
2233		return -1;
2234	}
2235#ifdef CONFIG_X86_64
2236	if (!cpu_has_apic) {
2237		disable_apic = 1;
2238		pr_info("Apic disabled by BIOS\n");
2239		return -1;
2240	}
2241#else
2242	if (!smp_found_config && !cpu_has_apic)
2243		return -1;
2244
2245	/*
2246	 * Complain if the BIOS pretends there is one.
2247	 */
2248	if (!cpu_has_apic &&
2249	    APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
2250		pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
2251			boot_cpu_physical_apicid);
2252		return -1;
2253	}
2254#endif
2255
2256	if (!smp_found_config)
2257		disable_ioapic_support();
2258
2259	default_setup_apic_routing();
2260	apic_bsp_setup(true);
2261	return 0;
2262}
2263
2264#ifdef CONFIG_UP_LATE_INIT
2265void __init up_late_init(void)
2266{
2267	APIC_init_uniprocessor();
2268}
2269#endif
2270
2271/*
2272 * Power management
2273 */
2274#ifdef CONFIG_PM
2275
2276static struct {
2277	/*
2278	 * 'active' is true if the local APIC was enabled by us and
2279	 * not the BIOS; this signifies that we are also responsible
2280	 * for disabling it before entering apm/acpi suspend
2281	 */
2282	int active;
2283	/* r/w apic fields */
2284	unsigned int apic_id;
2285	unsigned int apic_taskpri;
2286	unsigned int apic_ldr;
2287	unsigned int apic_dfr;
2288	unsigned int apic_spiv;
2289	unsigned int apic_lvtt;
2290	unsigned int apic_lvtpc;
2291	unsigned int apic_lvt0;
2292	unsigned int apic_lvt1;
2293	unsigned int apic_lvterr;
2294	unsigned int apic_tmict;
2295	unsigned int apic_tdcr;
2296	unsigned int apic_thmr;
2297	unsigned int apic_cmci;
2298} apic_pm_state;
2299
2300static int lapic_suspend(void)
2301{
2302	unsigned long flags;
2303	int maxlvt;
2304
2305	if (!apic_pm_state.active)
2306		return 0;
2307
2308	maxlvt = lapic_get_maxlvt();
2309
2310	apic_pm_state.apic_id = apic_read(APIC_ID);
2311	apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
2312	apic_pm_state.apic_ldr = apic_read(APIC_LDR);
2313	apic_pm_state.apic_dfr = apic_read(APIC_DFR);
2314	apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
2315	apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
2316	if (maxlvt >= 4)
2317		apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
2318	apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
2319	apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
2320	apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
2321	apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
2322	apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
2323#ifdef CONFIG_X86_THERMAL_VECTOR
2324	if (maxlvt >= 5)
2325		apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
2326#endif
2327#ifdef CONFIG_X86_MCE_INTEL
2328	if (maxlvt >= 6)
2329		apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
2330#endif
2331
2332	local_irq_save(flags);
2333	disable_local_APIC();
2334
2335	irq_remapping_disable();
 
2336
2337	local_irq_restore(flags);
2338	return 0;
2339}
2340
2341static void lapic_resume(void)
2342{
2343	unsigned int l, h;
2344	unsigned long flags;
2345	int maxlvt;
2346
2347	if (!apic_pm_state.active)
2348		return;
2349
2350	local_irq_save(flags);
 
 
 
 
 
 
 
 
 
 
2351
2352	/*
2353	 * IO-APIC and PIC have their own resume routines.
2354	 * We just mask them here to make sure the interrupt
2355	 * subsystem is completely quiet while we enable x2apic
2356	 * and interrupt-remapping.
2357	 */
2358	mask_ioapic_entries();
2359	legacy_pic->mask_all();
2360
2361	if (x2apic_mode) {
2362		__x2apic_enable();
2363	} else {
2364		/*
2365		 * Make sure the APICBASE points to the right address
2366		 *
2367		 * FIXME! This will be wrong if we ever support suspend on
2368		 * SMP! We'll need to do this as part of the CPU restore!
2369		 */
2370		if (boot_cpu_data.x86 >= 6) {
2371			rdmsr(MSR_IA32_APICBASE, l, h);
2372			l &= ~MSR_IA32_APICBASE_BASE;
2373			l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
2374			wrmsr(MSR_IA32_APICBASE, l, h);
2375		}
2376	}
2377
2378	maxlvt = lapic_get_maxlvt();
2379	apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
2380	apic_write(APIC_ID, apic_pm_state.apic_id);
2381	apic_write(APIC_DFR, apic_pm_state.apic_dfr);
2382	apic_write(APIC_LDR, apic_pm_state.apic_ldr);
2383	apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
2384	apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
2385	apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
2386	apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
2387#ifdef CONFIG_X86_THERMAL_VECTOR
2388	if (maxlvt >= 5)
2389		apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
2390#endif
2391#ifdef CONFIG_X86_MCE_INTEL
2392	if (maxlvt >= 6)
2393		apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
2394#endif
2395	if (maxlvt >= 4)
2396		apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
2397	apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
2398	apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
2399	apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
2400	apic_write(APIC_ESR, 0);
2401	apic_read(APIC_ESR);
2402	apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
2403	apic_write(APIC_ESR, 0);
2404	apic_read(APIC_ESR);
2405
2406	irq_remapping_reenable(x2apic_mode);
 
2407
2408	local_irq_restore(flags);
2409}
2410
2411/*
2412 * This device has no shutdown method - fully functioning local APICs
2413 * are needed on every CPU up until machine_halt/restart/poweroff.
2414 */
2415
2416static struct syscore_ops lapic_syscore_ops = {
2417	.resume		= lapic_resume,
2418	.suspend	= lapic_suspend,
2419};
2420
2421static void apic_pm_activate(void)
2422{
2423	apic_pm_state.active = 1;
2424}
2425
2426static int __init init_lapic_sysfs(void)
2427{
2428	/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
2429	if (cpu_has_apic)
2430		register_syscore_ops(&lapic_syscore_ops);
2431
2432	return 0;
2433}
2434
2435/* local apic needs to resume before other devices access its registers. */
2436core_initcall(init_lapic_sysfs);
2437
2438#else	/* CONFIG_PM */
2439
2440static void apic_pm_activate(void) { }
2441
2442#endif	/* CONFIG_PM */
2443
2444#ifdef CONFIG_X86_64
2445
2446static int multi_checked;
2447static int multi;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2448
2449static int set_multi(const struct dmi_system_id *d)
 
 
 
2450{
2451	if (multi)
2452		return 0;
2453	pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
2454	multi = 1;
2455	return 0;
2456}
2457
2458static const struct dmi_system_id multi_dmi_table[] = {
2459	{
2460		.callback = set_multi,
2461		.ident = "IBM System Summit2",
2462		.matches = {
2463			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2464			DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
2465		},
2466	},
2467	{}
2468};
2469
2470static void dmi_check_multi(void)
2471{
2472	if (multi_checked)
2473		return;
2474
2475	dmi_check_system(multi_dmi_table);
2476	multi_checked = 1;
2477}
2478
2479/*
2480 * apic_is_clustered_box() -- Check if we can expect good TSC
2481 *
2482 * Thus far, the major user of this is IBM's Summit2 series:
2483 * Clustered boxes may have unsynced TSC problems if they are
2484 * multi-chassis.
2485 * Use DMI to check them
2486 */
2487int apic_is_clustered_box(void)
2488{
2489	dmi_check_multi();
2490	return multi;
 
 
 
 
 
 
 
 
 
 
 
 
 
2491}
2492#endif
2493
2494/*
2495 * APIC command line parameters
2496 */
2497static int __init setup_disableapic(char *arg)
2498{
2499	disable_apic = 1;
2500	setup_clear_cpu_cap(X86_FEATURE_APIC);
2501	return 0;
2502}
2503early_param("disableapic", setup_disableapic);
2504
2505/* same as disableapic, for compatibility */
2506static int __init setup_nolapic(char *arg)
2507{
2508	return setup_disableapic(arg);
2509}
2510early_param("nolapic", setup_nolapic);
2511
2512static int __init parse_lapic_timer_c2_ok(char *arg)
2513{
2514	local_apic_timer_c2_ok = 1;
2515	return 0;
2516}
2517early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
2518
2519static int __init parse_disable_apic_timer(char *arg)
2520{
2521	disable_apic_timer = 1;
2522	return 0;
2523}
2524early_param("noapictimer", parse_disable_apic_timer);
2525
2526static int __init parse_nolapic_timer(char *arg)
2527{
2528	disable_apic_timer = 1;
2529	return 0;
2530}
2531early_param("nolapic_timer", parse_nolapic_timer);
2532
2533static int __init apic_set_verbosity(char *arg)
2534{
2535	if (!arg)  {
2536#ifdef CONFIG_X86_64
2537		skip_ioapic_setup = 0;
2538		return 0;
2539#endif
2540		return -EINVAL;
2541	}
2542
2543	if (strcmp("debug", arg) == 0)
2544		apic_verbosity = APIC_DEBUG;
2545	else if (strcmp("verbose", arg) == 0)
2546		apic_verbosity = APIC_VERBOSE;
2547	else {
2548		pr_warning("APIC Verbosity level %s not recognised"
2549			" use apic=verbose or apic=debug\n", arg);
2550		return -EINVAL;
2551	}
2552
2553	return 0;
2554}
2555early_param("apic", apic_set_verbosity);
2556
2557static int __init lapic_insert_resource(void)
2558{
2559	if (!apic_phys)
2560		return -1;
2561
2562	/* Put local APIC into the resource map. */
2563	lapic_resource.start = apic_phys;
2564	lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
2565	insert_resource(&iomem_resource, &lapic_resource);
2566
2567	return 0;
2568}
2569
2570/*
2571 * need call insert after e820_reserve_resources()
2572 * that is using request_resource
2573 */
2574late_initcall(lapic_insert_resource);
2575
2576static int __init apic_set_disabled_cpu_apicid(char *arg)
2577{
2578	if (!arg || !get_option(&arg, &disabled_cpu_apicid))
2579		return -EINVAL;
2580
2581	return 0;
2582}
2583early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
2584
2585static int __init apic_set_extnmi(char *arg)
2586{
2587	if (!arg)
2588		return -EINVAL;
2589
2590	if (!strncmp("all", arg, 3))
2591		apic_extnmi = APIC_EXTNMI_ALL;
2592	else if (!strncmp("none", arg, 4))
2593		apic_extnmi = APIC_EXTNMI_NONE;
2594	else if (!strncmp("bsp", arg, 3))
2595		apic_extnmi = APIC_EXTNMI_BSP;
2596	else {
2597		pr_warn("Unknown external NMI delivery mode `%s' ignored\n", arg);
2598		return -EINVAL;
2599	}
2600
2601	return 0;
2602}
2603early_param("apic_extnmi", apic_set_extnmi);