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 59 unsigned int num_processors; 60 61 unsigned disabled_cpus; 62 63 /* Processor that is doing the boot up */ 64 unsigned int boot_cpu_physical_apicid = -1U; 65 EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid); 66 67 /* 68 * The highest APIC ID seen during enumeration. 69 */ 70 static unsigned int max_physical_apicid; 71 72 /* 73 * Bitmask of physically existing CPUs: 74 */ 75 physid_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 */ 82 static unsigned int disabled_cpu_apicid __read_mostly = BAD_APICID; 83 84 /* 85 * Map cpu index to physical APIC ID 86 */ 87 DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID); 88 DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID); 89 EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid); 90 EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid); 91 92 #ifdef CONFIG_X86_32 93 94 /* 95 * On x86_32, the mapping between cpu and logical apicid may vary 96 * depending on apic in use. The following early percpu variable is 97 * used for the mapping. This is where the behaviors of x86_64 and 32 98 * actually diverge. Let's keep it ugly for now. 99 */ 100 DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID); 101 102 /* Local APIC was disabled by the BIOS and enabled by the kernel */ 103 static int enabled_via_apicbase; 104 105 /* 106 * Handle interrupt mode configuration register (IMCR). 107 * This register controls whether the interrupt signals 108 * that reach the BSP come from the master PIC or from the 109 * local APIC. Before entering Symmetric I/O Mode, either 110 * the BIOS or the operating system must switch out of 111 * PIC Mode by changing the IMCR. 112 */ 113 static inline void imcr_pic_to_apic(void) 114 { 115 /* select IMCR register */ 116 outb(0x70, 0x22); 117 /* NMI and 8259 INTR go through APIC */ 118 outb(0x01, 0x23); 119 } 120 121 static inline void imcr_apic_to_pic(void) 122 { 123 /* select IMCR register */ 124 outb(0x70, 0x22); 125 /* NMI and 8259 INTR go directly to BSP */ 126 outb(0x00, 0x23); 127 } 128 #endif 129 130 /* 131 * Knob to control our willingness to enable the local APIC. 132 * 133 * +1=force-enable 134 */ 135 static int force_enable_local_apic __initdata; 136 137 /* Control whether x2APIC mode is enabled or not */ 138 static bool nox2apic __initdata; 139 140 /* 141 * APIC command line parameters 142 */ 143 static int __init parse_lapic(char *arg) 144 { 145 if (config_enabled(CONFIG_X86_32) && !arg) 146 force_enable_local_apic = 1; 147 else if (arg && !strncmp(arg, "notscdeadline", 13)) 148 setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER); 149 return 0; 150 } 151 early_param("lapic", parse_lapic); 152 153 #ifdef CONFIG_X86_64 154 static int apic_calibrate_pmtmr __initdata; 155 static __init int setup_apicpmtimer(char *s) 156 { 157 apic_calibrate_pmtmr = 1; 158 notsc_setup(NULL); 159 return 0; 160 } 161 __setup("apicpmtimer", setup_apicpmtimer); 162 #endif 163 164 int x2apic_mode; 165 #ifdef CONFIG_X86_X2APIC 166 /* x2apic enabled before OS handover */ 167 int x2apic_preenabled; 168 static int x2apic_disabled; 169 static int __init setup_nox2apic(char *str) 170 { 171 if (x2apic_enabled()) { 172 int apicid = native_apic_msr_read(APIC_ID); 173 174 if (apicid >= 255) { 175 pr_warning("Apicid: %08x, cannot enforce nox2apic\n", 176 apicid); 177 return 0; 178 } 179 180 pr_warning("x2apic already enabled. will disable it\n"); 181 } else 182 setup_clear_cpu_cap(X86_FEATURE_X2APIC); 183 184 nox2apic = true; 185 186 return 0; 187 } 188 early_param("nox2apic", setup_nox2apic); 189 #endif 190 191 unsigned long mp_lapic_addr; 192 int disable_apic; 193 /* Disable local APIC timer from the kernel commandline or via dmi quirk */ 194 static int disable_apic_timer __initdata; 195 /* Local APIC timer works in C2 */ 196 int local_apic_timer_c2_ok; 197 EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok); 198 199 int first_system_vector = 0xfe; 200 201 /* 202 * Debug level, exported for io_apic.c 203 */ 204 unsigned int apic_verbosity; 205 206 int pic_mode; 207 208 /* Have we found an MP table */ 209 int smp_found_config; 210 211 static struct resource lapic_resource = { 212 .name = "Local APIC", 213 .flags = IORESOURCE_MEM | IORESOURCE_BUSY, 214 }; 215 216 unsigned int lapic_timer_frequency = 0; 217 218 static void apic_pm_activate(void); 219 220 static unsigned long apic_phys; 221 222 /* 223 * Get the LAPIC version 224 */ 225 static inline int lapic_get_version(void) 226 { 227 return GET_APIC_VERSION(apic_read(APIC_LVR)); 228 } 229 230 /* 231 * Check, if the APIC is integrated or a separate chip 232 */ 233 static inline int lapic_is_integrated(void) 234 { 235 #ifdef CONFIG_X86_64 236 return 1; 237 #else 238 return APIC_INTEGRATED(lapic_get_version()); 239 #endif 240 } 241 242 /* 243 * Check, whether this is a modern or a first generation APIC 244 */ 245 static int modern_apic(void) 246 { 247 /* AMD systems use old APIC versions, so check the CPU */ 248 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && 249 boot_cpu_data.x86 >= 0xf) 250 return 1; 251 return lapic_get_version() >= 0x14; 252 } 253 254 /* 255 * right after this call apic become NOOP driven 256 * so apic->write/read doesn't do anything 257 */ 258 static void __init apic_disable(void) 259 { 260 pr_info("APIC: switched to apic NOOP\n"); 261 apic = &apic_noop; 262 } 263 264 void native_apic_wait_icr_idle(void) 265 { 266 while (apic_read(APIC_ICR) & APIC_ICR_BUSY) 267 cpu_relax(); 268 } 269 270 u32 native_safe_apic_wait_icr_idle(void) 271 { 272 u32 send_status; 273 int timeout; 274 275 timeout = 0; 276 do { 277 send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY; 278 if (!send_status) 279 break; 280 inc_irq_stat(icr_read_retry_count); 281 udelay(100); 282 } while (timeout++ < 1000); 283 284 return send_status; 285 } 286 287 void native_apic_icr_write(u32 low, u32 id) 288 { 289 unsigned long flags; 290 291 local_irq_save(flags); 292 apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id)); 293 apic_write(APIC_ICR, low); 294 local_irq_restore(flags); 295 } 296 297 u64 native_apic_icr_read(void) 298 { 299 u32 icr1, icr2; 300 301 icr2 = apic_read(APIC_ICR2); 302 icr1 = apic_read(APIC_ICR); 303 304 return icr1 | ((u64)icr2 << 32); 305 } 306 307 #ifdef CONFIG_X86_32 308 /** 309 * get_physical_broadcast - Get number of physical broadcast IDs 310 */ 311 int get_physical_broadcast(void) 312 { 313 return modern_apic() ? 0xff : 0xf; 314 } 315 #endif 316 317 /** 318 * lapic_get_maxlvt - get the maximum number of local vector table entries 319 */ 320 int lapic_get_maxlvt(void) 321 { 322 unsigned int v; 323 324 v = apic_read(APIC_LVR); 325 /* 326 * - we always have APIC integrated on 64bit mode 327 * - 82489DXs do not report # of LVT entries 328 */ 329 return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2; 330 } 331 332 /* 333 * Local APIC timer 334 */ 335 336 /* Clock divisor */ 337 #define APIC_DIVISOR 16 338 #define TSC_DIVISOR 32 339 340 /* 341 * This function sets up the local APIC timer, with a timeout of 342 * 'clocks' APIC bus clock. During calibration we actually call 343 * this function twice on the boot CPU, once with a bogus timeout 344 * value, second time for real. The other (noncalibrating) CPUs 345 * call this function only once, with the real, calibrated value. 346 * 347 * We do reads before writes even if unnecessary, to get around the 348 * P5 APIC double write bug. 349 */ 350 static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen) 351 { 352 unsigned int lvtt_value, tmp_value; 353 354 lvtt_value = LOCAL_TIMER_VECTOR; 355 if (!oneshot) 356 lvtt_value |= APIC_LVT_TIMER_PERIODIC; 357 else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) 358 lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE; 359 360 if (!lapic_is_integrated()) 361 lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV); 362 363 if (!irqen) 364 lvtt_value |= APIC_LVT_MASKED; 365 366 apic_write(APIC_LVTT, lvtt_value); 367 368 if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) { 369 printk_once(KERN_DEBUG "TSC deadline timer enabled\n"); 370 return; 371 } 372 373 /* 374 * Divide PICLK by 16 375 */ 376 tmp_value = apic_read(APIC_TDCR); 377 apic_write(APIC_TDCR, 378 (tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) | 379 APIC_TDR_DIV_16); 380 381 if (!oneshot) 382 apic_write(APIC_TMICT, clocks / APIC_DIVISOR); 383 } 384 385 /* 386 * Setup extended LVT, AMD specific 387 * 388 * Software should use the LVT offsets the BIOS provides. The offsets 389 * are determined by the subsystems using it like those for MCE 390 * threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts 391 * are supported. Beginning with family 10h at least 4 offsets are 392 * available. 393 * 394 * Since the offsets must be consistent for all cores, we keep track 395 * of the LVT offsets in software and reserve the offset for the same 396 * vector also to be used on other cores. An offset is freed by 397 * setting the entry to APIC_EILVT_MASKED. 398 * 399 * If the BIOS is right, there should be no conflicts. Otherwise a 400 * "[Firmware Bug]: ..." error message is generated. However, if 401 * software does not properly determines the offsets, it is not 402 * necessarily a BIOS bug. 403 */ 404 405 static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX]; 406 407 static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new) 408 { 409 return (old & APIC_EILVT_MASKED) 410 || (new == APIC_EILVT_MASKED) 411 || ((new & ~APIC_EILVT_MASKED) == old); 412 } 413 414 static unsigned int reserve_eilvt_offset(int offset, unsigned int new) 415 { 416 unsigned int rsvd, vector; 417 418 if (offset >= APIC_EILVT_NR_MAX) 419 return ~0; 420 421 rsvd = atomic_read(&eilvt_offsets[offset]); 422 do { 423 vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */ 424 if (vector && !eilvt_entry_is_changeable(vector, new)) 425 /* may not change if vectors are different */ 426 return rsvd; 427 rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new); 428 } while (rsvd != new); 429 430 rsvd &= ~APIC_EILVT_MASKED; 431 if (rsvd && rsvd != vector) 432 pr_info("LVT offset %d assigned for vector 0x%02x\n", 433 offset, rsvd); 434 435 return new; 436 } 437 438 /* 439 * If mask=1, the LVT entry does not generate interrupts while mask=0 440 * enables the vector. See also the BKDGs. Must be called with 441 * preemption disabled. 442 */ 443 444 int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask) 445 { 446 unsigned long reg = APIC_EILVTn(offset); 447 unsigned int new, old, reserved; 448 449 new = (mask << 16) | (msg_type << 8) | vector; 450 old = apic_read(reg); 451 reserved = reserve_eilvt_offset(offset, new); 452 453 if (reserved != new) { 454 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for " 455 "vector 0x%x, but the register is already in use for " 456 "vector 0x%x on another cpu\n", 457 smp_processor_id(), reg, offset, new, reserved); 458 return -EINVAL; 459 } 460 461 if (!eilvt_entry_is_changeable(old, new)) { 462 pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for " 463 "vector 0x%x, but the register is already in use for " 464 "vector 0x%x on this cpu\n", 465 smp_processor_id(), reg, offset, new, old); 466 return -EBUSY; 467 } 468 469 apic_write(reg, new); 470 471 return 0; 472 } 473 EXPORT_SYMBOL_GPL(setup_APIC_eilvt); 474 475 /* 476 * Program the next event, relative to now 477 */ 478 static int lapic_next_event(unsigned long delta, 479 struct clock_event_device *evt) 480 { 481 apic_write(APIC_TMICT, delta); 482 return 0; 483 } 484 485 static int lapic_next_deadline(unsigned long delta, 486 struct clock_event_device *evt) 487 { 488 u64 tsc; 489 490 rdtscll(tsc); 491 wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR)); 492 return 0; 493 } 494 495 /* 496 * Setup the lapic timer in periodic or oneshot mode 497 */ 498 static void lapic_timer_setup(enum clock_event_mode mode, 499 struct clock_event_device *evt) 500 { 501 unsigned long flags; 502 unsigned int v; 503 504 /* Lapic used as dummy for broadcast ? */ 505 if (evt->features & CLOCK_EVT_FEAT_DUMMY) 506 return; 507 508 local_irq_save(flags); 509 510 switch (mode) { 511 case CLOCK_EVT_MODE_PERIODIC: 512 case CLOCK_EVT_MODE_ONESHOT: 513 __setup_APIC_LVTT(lapic_timer_frequency, 514 mode != CLOCK_EVT_MODE_PERIODIC, 1); 515 break; 516 case CLOCK_EVT_MODE_UNUSED: 517 case CLOCK_EVT_MODE_SHUTDOWN: 518 v = apic_read(APIC_LVTT); 519 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR); 520 apic_write(APIC_LVTT, v); 521 apic_write(APIC_TMICT, 0); 522 break; 523 case CLOCK_EVT_MODE_RESUME: 524 /* Nothing to do here */ 525 break; 526 } 527 528 local_irq_restore(flags); 529 } 530 531 /* 532 * Local APIC timer broadcast function 533 */ 534 static void lapic_timer_broadcast(const struct cpumask *mask) 535 { 536 #ifdef CONFIG_SMP 537 apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR); 538 #endif 539 } 540 541 542 /* 543 * The local apic timer can be used for any function which is CPU local. 544 */ 545 static struct clock_event_device lapic_clockevent = { 546 .name = "lapic", 547 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT 548 | CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY, 549 .shift = 32, 550 .set_mode = lapic_timer_setup, 551 .set_next_event = lapic_next_event, 552 .broadcast = lapic_timer_broadcast, 553 .rating = 100, 554 .irq = -1, 555 }; 556 static DEFINE_PER_CPU(struct clock_event_device, lapic_events); 557 558 /* 559 * Setup the local APIC timer for this CPU. Copy the initialized values 560 * of the boot CPU and register the clock event in the framework. 561 */ 562 static void setup_APIC_timer(void) 563 { 564 struct clock_event_device *levt = &__get_cpu_var(lapic_events); 565 566 if (this_cpu_has(X86_FEATURE_ARAT)) { 567 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP; 568 /* Make LAPIC timer preferrable over percpu HPET */ 569 lapic_clockevent.rating = 150; 570 } 571 572 memcpy(levt, &lapic_clockevent, sizeof(*levt)); 573 levt->cpumask = cpumask_of(smp_processor_id()); 574 575 if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) { 576 levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC | 577 CLOCK_EVT_FEAT_DUMMY); 578 levt->set_next_event = lapic_next_deadline; 579 clockevents_config_and_register(levt, 580 (tsc_khz / TSC_DIVISOR) * 1000, 581 0xF, ~0UL); 582 } else 583 clockevents_register_device(levt); 584 } 585 586 /* 587 * In this functions we calibrate APIC bus clocks to the external timer. 588 * 589 * We want to do the calibration only once since we want to have local timer 590 * irqs syncron. CPUs connected by the same APIC bus have the very same bus 591 * frequency. 592 * 593 * This was previously done by reading the PIT/HPET and waiting for a wrap 594 * around to find out, that a tick has elapsed. I have a box, where the PIT 595 * readout is broken, so it never gets out of the wait loop again. This was 596 * also reported by others. 597 * 598 * Monitoring the jiffies value is inaccurate and the clockevents 599 * infrastructure allows us to do a simple substitution of the interrupt 600 * handler. 601 * 602 * The calibration routine also uses the pm_timer when possible, as the PIT 603 * happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes 604 * back to normal later in the boot process). 605 */ 606 607 #define LAPIC_CAL_LOOPS (HZ/10) 608 609 static __initdata int lapic_cal_loops = -1; 610 static __initdata long lapic_cal_t1, lapic_cal_t2; 611 static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2; 612 static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2; 613 static __initdata unsigned long lapic_cal_j1, lapic_cal_j2; 614 615 /* 616 * Temporary interrupt handler. 617 */ 618 static void __init lapic_cal_handler(struct clock_event_device *dev) 619 { 620 unsigned long long tsc = 0; 621 long tapic = apic_read(APIC_TMCCT); 622 unsigned long pm = acpi_pm_read_early(); 623 624 if (cpu_has_tsc) 625 rdtscll(tsc); 626 627 switch (lapic_cal_loops++) { 628 case 0: 629 lapic_cal_t1 = tapic; 630 lapic_cal_tsc1 = tsc; 631 lapic_cal_pm1 = pm; 632 lapic_cal_j1 = jiffies; 633 break; 634 635 case LAPIC_CAL_LOOPS: 636 lapic_cal_t2 = tapic; 637 lapic_cal_tsc2 = tsc; 638 if (pm < lapic_cal_pm1) 639 pm += ACPI_PM_OVRRUN; 640 lapic_cal_pm2 = pm; 641 lapic_cal_j2 = jiffies; 642 break; 643 } 644 } 645 646 static int __init 647 calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc) 648 { 649 const long pm_100ms = PMTMR_TICKS_PER_SEC / 10; 650 const long pm_thresh = pm_100ms / 100; 651 unsigned long mult; 652 u64 res; 653 654 #ifndef CONFIG_X86_PM_TIMER 655 return -1; 656 #endif 657 658 apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm); 659 660 /* Check, if the PM timer is available */ 661 if (!deltapm) 662 return -1; 663 664 mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22); 665 666 if (deltapm > (pm_100ms - pm_thresh) && 667 deltapm < (pm_100ms + pm_thresh)) { 668 apic_printk(APIC_VERBOSE, "... PM-Timer result ok\n"); 669 return 0; 670 } 671 672 res = (((u64)deltapm) * mult) >> 22; 673 do_div(res, 1000000); 674 pr_warning("APIC calibration not consistent " 675 "with PM-Timer: %ldms instead of 100ms\n",(long)res); 676 677 /* Correct the lapic counter value */ 678 res = (((u64)(*delta)) * pm_100ms); 679 do_div(res, deltapm); 680 pr_info("APIC delta adjusted to PM-Timer: " 681 "%lu (%ld)\n", (unsigned long)res, *delta); 682 *delta = (long)res; 683 684 /* Correct the tsc counter value */ 685 if (cpu_has_tsc) { 686 res = (((u64)(*deltatsc)) * pm_100ms); 687 do_div(res, deltapm); 688 apic_printk(APIC_VERBOSE, "TSC delta adjusted to " 689 "PM-Timer: %lu (%ld)\n", 690 (unsigned long)res, *deltatsc); 691 *deltatsc = (long)res; 692 } 693 694 return 0; 695 } 696 697 static int __init calibrate_APIC_clock(void) 698 { 699 struct clock_event_device *levt = &__get_cpu_var(lapic_events); 700 void (*real_handler)(struct clock_event_device *dev); 701 unsigned long deltaj; 702 long delta, deltatsc; 703 int pm_referenced = 0; 704 705 /** 706 * check if lapic timer has already been calibrated by platform 707 * specific routine, such as tsc calibration code. if so, we just fill 708 * in the clockevent structure and return. 709 */ 710 711 if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) { 712 return 0; 713 } else if (lapic_timer_frequency) { 714 apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n", 715 lapic_timer_frequency); 716 lapic_clockevent.mult = div_sc(lapic_timer_frequency/APIC_DIVISOR, 717 TICK_NSEC, lapic_clockevent.shift); 718 lapic_clockevent.max_delta_ns = 719 clockevent_delta2ns(0x7FFFFF, &lapic_clockevent); 720 lapic_clockevent.min_delta_ns = 721 clockevent_delta2ns(0xF, &lapic_clockevent); 722 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; 723 return 0; 724 } 725 726 apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n" 727 "calibrating APIC timer ...\n"); 728 729 local_irq_disable(); 730 731 /* Replace the global interrupt handler */ 732 real_handler = global_clock_event->event_handler; 733 global_clock_event->event_handler = lapic_cal_handler; 734 735 /* 736 * Setup the APIC counter to maximum. There is no way the lapic 737 * can underflow in the 100ms detection time frame 738 */ 739 __setup_APIC_LVTT(0xffffffff, 0, 0); 740 741 /* Let the interrupts run */ 742 local_irq_enable(); 743 744 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) 745 cpu_relax(); 746 747 local_irq_disable(); 748 749 /* Restore the real event handler */ 750 global_clock_event->event_handler = real_handler; 751 752 /* Build delta t1-t2 as apic timer counts down */ 753 delta = lapic_cal_t1 - lapic_cal_t2; 754 apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta); 755 756 deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1); 757 758 /* we trust the PM based calibration if possible */ 759 pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1, 760 &delta, &deltatsc); 761 762 /* Calculate the scaled math multiplication factor */ 763 lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS, 764 lapic_clockevent.shift); 765 lapic_clockevent.max_delta_ns = 766 clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent); 767 lapic_clockevent.min_delta_ns = 768 clockevent_delta2ns(0xF, &lapic_clockevent); 769 770 lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS; 771 772 apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta); 773 apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult); 774 apic_printk(APIC_VERBOSE, "..... calibration result: %u\n", 775 lapic_timer_frequency); 776 777 if (cpu_has_tsc) { 778 apic_printk(APIC_VERBOSE, "..... CPU clock speed is " 779 "%ld.%04ld MHz.\n", 780 (deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ), 781 (deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ)); 782 } 783 784 apic_printk(APIC_VERBOSE, "..... host bus clock speed is " 785 "%u.%04u MHz.\n", 786 lapic_timer_frequency / (1000000 / HZ), 787 lapic_timer_frequency % (1000000 / HZ)); 788 789 /* 790 * Do a sanity check on the APIC calibration result 791 */ 792 if (lapic_timer_frequency < (1000000 / HZ)) { 793 local_irq_enable(); 794 pr_warning("APIC frequency too slow, disabling apic timer\n"); 795 return -1; 796 } 797 798 levt->features &= ~CLOCK_EVT_FEAT_DUMMY; 799 800 /* 801 * PM timer calibration failed or not turned on 802 * so lets try APIC timer based calibration 803 */ 804 if (!pm_referenced) { 805 apic_printk(APIC_VERBOSE, "... verify APIC timer\n"); 806 807 /* 808 * Setup the apic timer manually 809 */ 810 levt->event_handler = lapic_cal_handler; 811 lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt); 812 lapic_cal_loops = -1; 813 814 /* Let the interrupts run */ 815 local_irq_enable(); 816 817 while (lapic_cal_loops <= LAPIC_CAL_LOOPS) 818 cpu_relax(); 819 820 /* Stop the lapic timer */ 821 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt); 822 823 /* Jiffies delta */ 824 deltaj = lapic_cal_j2 - lapic_cal_j1; 825 apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj); 826 827 /* Check, if the jiffies result is consistent */ 828 if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2) 829 apic_printk(APIC_VERBOSE, "... jiffies result ok\n"); 830 else 831 levt->features |= CLOCK_EVT_FEAT_DUMMY; 832 } else 833 local_irq_enable(); 834 835 if (levt->features & CLOCK_EVT_FEAT_DUMMY) { 836 pr_warning("APIC timer disabled due to verification failure\n"); 837 return -1; 838 } 839 840 return 0; 841 } 842 843 /* 844 * Setup the boot APIC 845 * 846 * Calibrate and verify the result. 847 */ 848 void __init setup_boot_APIC_clock(void) 849 { 850 /* 851 * The local apic timer can be disabled via the kernel 852 * commandline or from the CPU detection code. Register the lapic 853 * timer as a dummy clock event source on SMP systems, so the 854 * broadcast mechanism is used. On UP systems simply ignore it. 855 */ 856 if (disable_apic_timer) { 857 pr_info("Disabling APIC timer\n"); 858 /* No broadcast on UP ! */ 859 if (num_possible_cpus() > 1) { 860 lapic_clockevent.mult = 1; 861 setup_APIC_timer(); 862 } 863 return; 864 } 865 866 if (calibrate_APIC_clock()) { 867 /* No broadcast on UP ! */ 868 if (num_possible_cpus() > 1) 869 setup_APIC_timer(); 870 return; 871 } 872 873 /* 874 * If nmi_watchdog is set to IO_APIC, we need the 875 * PIT/HPET going. Otherwise register lapic as a dummy 876 * device. 877 */ 878 lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY; 879 880 /* Setup the lapic or request the broadcast */ 881 setup_APIC_timer(); 882 } 883 884 void setup_secondary_APIC_clock(void) 885 { 886 setup_APIC_timer(); 887 } 888 889 /* 890 * The guts of the apic timer interrupt 891 */ 892 static void local_apic_timer_interrupt(void) 893 { 894 int cpu = smp_processor_id(); 895 struct clock_event_device *evt = &per_cpu(lapic_events, cpu); 896 897 /* 898 * Normally we should not be here till LAPIC has been initialized but 899 * in some cases like kdump, its possible that there is a pending LAPIC 900 * timer interrupt from previous kernel's context and is delivered in 901 * new kernel the moment interrupts are enabled. 902 * 903 * Interrupts are enabled early and LAPIC is setup much later, hence 904 * its possible that when we get here evt->event_handler is NULL. 905 * Check for event_handler being NULL and discard the interrupt as 906 * spurious. 907 */ 908 if (!evt->event_handler) { 909 pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu); 910 /* Switch it off */ 911 lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt); 912 return; 913 } 914 915 /* 916 * the NMI deadlock-detector uses this. 917 */ 918 inc_irq_stat(apic_timer_irqs); 919 920 evt->event_handler(evt); 921 } 922 923 /* 924 * Local APIC timer interrupt. This is the most natural way for doing 925 * local interrupts, but local timer interrupts can be emulated by 926 * broadcast interrupts too. [in case the hw doesn't support APIC timers] 927 * 928 * [ if a single-CPU system runs an SMP kernel then we call the local 929 * interrupt as well. Thus we cannot inline the local irq ... ] 930 */ 931 __visible void __irq_entry smp_apic_timer_interrupt(struct pt_regs *regs) 932 { 933 struct pt_regs *old_regs = set_irq_regs(regs); 934 935 /* 936 * NOTE! We'd better ACK the irq immediately, 937 * because timer handling can be slow. 938 * 939 * update_process_times() expects us to have done irq_enter(). 940 * Besides, if we don't timer interrupts ignore the global 941 * interrupt lock, which is the WrongThing (tm) to do. 942 */ 943 entering_ack_irq(); 944 local_apic_timer_interrupt(); 945 exiting_irq(); 946 947 set_irq_regs(old_regs); 948 } 949 950 __visible void __irq_entry smp_trace_apic_timer_interrupt(struct pt_regs *regs) 951 { 952 struct pt_regs *old_regs = set_irq_regs(regs); 953 954 /* 955 * NOTE! We'd better ACK the irq immediately, 956 * because timer handling can be slow. 957 * 958 * update_process_times() expects us to have done irq_enter(). 959 * Besides, if we don't timer interrupts ignore the global 960 * interrupt lock, which is the WrongThing (tm) to do. 961 */ 962 entering_ack_irq(); 963 trace_local_timer_entry(LOCAL_TIMER_VECTOR); 964 local_apic_timer_interrupt(); 965 trace_local_timer_exit(LOCAL_TIMER_VECTOR); 966 exiting_irq(); 967 968 set_irq_regs(old_regs); 969 } 970 971 int setup_profiling_timer(unsigned int multiplier) 972 { 973 return -EINVAL; 974 } 975 976 /* 977 * Local APIC start and shutdown 978 */ 979 980 /** 981 * clear_local_APIC - shutdown the local APIC 982 * 983 * This is called, when a CPU is disabled and before rebooting, so the state of 984 * the local APIC has no dangling leftovers. Also used to cleanout any BIOS 985 * leftovers during boot. 986 */ 987 void clear_local_APIC(void) 988 { 989 int maxlvt; 990 u32 v; 991 992 /* APIC hasn't been mapped yet */ 993 if (!x2apic_mode && !apic_phys) 994 return; 995 996 maxlvt = lapic_get_maxlvt(); 997 /* 998 * Masking an LVT entry can trigger a local APIC error 999 * if the vector is zero. Mask LVTERR first to prevent this. 1000 */ 1001 if (maxlvt >= 3) { 1002 v = ERROR_APIC_VECTOR; /* any non-zero vector will do */ 1003 apic_write(APIC_LVTERR, v | APIC_LVT_MASKED); 1004 } 1005 /* 1006 * Careful: we have to set masks only first to deassert 1007 * any level-triggered sources. 1008 */ 1009 v = apic_read(APIC_LVTT); 1010 apic_write(APIC_LVTT, v | APIC_LVT_MASKED); 1011 v = apic_read(APIC_LVT0); 1012 apic_write(APIC_LVT0, v | APIC_LVT_MASKED); 1013 v = apic_read(APIC_LVT1); 1014 apic_write(APIC_LVT1, v | APIC_LVT_MASKED); 1015 if (maxlvt >= 4) { 1016 v = apic_read(APIC_LVTPC); 1017 apic_write(APIC_LVTPC, v | APIC_LVT_MASKED); 1018 } 1019 1020 /* lets not touch this if we didn't frob it */ 1021 #ifdef CONFIG_X86_THERMAL_VECTOR 1022 if (maxlvt >= 5) { 1023 v = apic_read(APIC_LVTTHMR); 1024 apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED); 1025 } 1026 #endif 1027 #ifdef CONFIG_X86_MCE_INTEL 1028 if (maxlvt >= 6) { 1029 v = apic_read(APIC_LVTCMCI); 1030 if (!(v & APIC_LVT_MASKED)) 1031 apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED); 1032 } 1033 #endif 1034 1035 /* 1036 * Clean APIC state for other OSs: 1037 */ 1038 apic_write(APIC_LVTT, APIC_LVT_MASKED); 1039 apic_write(APIC_LVT0, APIC_LVT_MASKED); 1040 apic_write(APIC_LVT1, APIC_LVT_MASKED); 1041 if (maxlvt >= 3) 1042 apic_write(APIC_LVTERR, APIC_LVT_MASKED); 1043 if (maxlvt >= 4) 1044 apic_write(APIC_LVTPC, APIC_LVT_MASKED); 1045 1046 /* Integrated APIC (!82489DX) ? */ 1047 if (lapic_is_integrated()) { 1048 if (maxlvt > 3) 1049 /* Clear ESR due to Pentium errata 3AP and 11AP */ 1050 apic_write(APIC_ESR, 0); 1051 apic_read(APIC_ESR); 1052 } 1053 } 1054 1055 /** 1056 * disable_local_APIC - clear and disable the local APIC 1057 */ 1058 void disable_local_APIC(void) 1059 { 1060 unsigned int value; 1061 1062 /* APIC hasn't been mapped yet */ 1063 if (!x2apic_mode && !apic_phys) 1064 return; 1065 1066 clear_local_APIC(); 1067 1068 /* 1069 * Disable APIC (implies clearing of registers 1070 * for 82489DX!). 1071 */ 1072 value = apic_read(APIC_SPIV); 1073 value &= ~APIC_SPIV_APIC_ENABLED; 1074 apic_write(APIC_SPIV, value); 1075 1076 #ifdef CONFIG_X86_32 1077 /* 1078 * When LAPIC was disabled by the BIOS and enabled by the kernel, 1079 * restore the disabled state. 1080 */ 1081 if (enabled_via_apicbase) { 1082 unsigned int l, h; 1083 1084 rdmsr(MSR_IA32_APICBASE, l, h); 1085 l &= ~MSR_IA32_APICBASE_ENABLE; 1086 wrmsr(MSR_IA32_APICBASE, l, h); 1087 } 1088 #endif 1089 } 1090 1091 /* 1092 * If Linux enabled the LAPIC against the BIOS default disable it down before 1093 * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and 1094 * not power-off. Additionally clear all LVT entries before disable_local_APIC 1095 * for the case where Linux didn't enable the LAPIC. 1096 */ 1097 void lapic_shutdown(void) 1098 { 1099 unsigned long flags; 1100 1101 if (!cpu_has_apic && !apic_from_smp_config()) 1102 return; 1103 1104 local_irq_save(flags); 1105 1106 #ifdef CONFIG_X86_32 1107 if (!enabled_via_apicbase) 1108 clear_local_APIC(); 1109 else 1110 #endif 1111 disable_local_APIC(); 1112 1113 1114 local_irq_restore(flags); 1115 } 1116 1117 /* 1118 * This is to verify that we're looking at a real local APIC. 1119 * Check these against your board if the CPUs aren't getting 1120 * started for no apparent reason. 1121 */ 1122 int __init verify_local_APIC(void) 1123 { 1124 unsigned int reg0, reg1; 1125 1126 /* 1127 * The version register is read-only in a real APIC. 1128 */ 1129 reg0 = apic_read(APIC_LVR); 1130 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0); 1131 apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK); 1132 reg1 = apic_read(APIC_LVR); 1133 apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1); 1134 1135 /* 1136 * The two version reads above should print the same 1137 * numbers. If the second one is different, then we 1138 * poke at a non-APIC. 1139 */ 1140 if (reg1 != reg0) 1141 return 0; 1142 1143 /* 1144 * Check if the version looks reasonably. 1145 */ 1146 reg1 = GET_APIC_VERSION(reg0); 1147 if (reg1 == 0x00 || reg1 == 0xff) 1148 return 0; 1149 reg1 = lapic_get_maxlvt(); 1150 if (reg1 < 0x02 || reg1 == 0xff) 1151 return 0; 1152 1153 /* 1154 * The ID register is read/write in a real APIC. 1155 */ 1156 reg0 = apic_read(APIC_ID); 1157 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0); 1158 apic_write(APIC_ID, reg0 ^ apic->apic_id_mask); 1159 reg1 = apic_read(APIC_ID); 1160 apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1); 1161 apic_write(APIC_ID, reg0); 1162 if (reg1 != (reg0 ^ apic->apic_id_mask)) 1163 return 0; 1164 1165 /* 1166 * The next two are just to see if we have sane values. 1167 * They're only really relevant if we're in Virtual Wire 1168 * compatibility mode, but most boxes are anymore. 1169 */ 1170 reg0 = apic_read(APIC_LVT0); 1171 apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0); 1172 reg1 = apic_read(APIC_LVT1); 1173 apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1); 1174 1175 return 1; 1176 } 1177 1178 /** 1179 * sync_Arb_IDs - synchronize APIC bus arbitration IDs 1180 */ 1181 void __init sync_Arb_IDs(void) 1182 { 1183 /* 1184 * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not 1185 * needed on AMD. 1186 */ 1187 if (modern_apic() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD) 1188 return; 1189 1190 /* 1191 * Wait for idle. 1192 */ 1193 apic_wait_icr_idle(); 1194 1195 apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n"); 1196 apic_write(APIC_ICR, APIC_DEST_ALLINC | 1197 APIC_INT_LEVELTRIG | APIC_DM_INIT); 1198 } 1199 1200 /* 1201 * An initial setup of the virtual wire mode. 1202 */ 1203 void __init init_bsp_APIC(void) 1204 { 1205 unsigned int value; 1206 1207 /* 1208 * Don't do the setup now if we have a SMP BIOS as the 1209 * through-I/O-APIC virtual wire mode might be active. 1210 */ 1211 if (smp_found_config || !cpu_has_apic) 1212 return; 1213 1214 /* 1215 * Do not trust the local APIC being empty at bootup. 1216 */ 1217 clear_local_APIC(); 1218 1219 /* 1220 * Enable APIC. 1221 */ 1222 value = apic_read(APIC_SPIV); 1223 value &= ~APIC_VECTOR_MASK; 1224 value |= APIC_SPIV_APIC_ENABLED; 1225 1226 #ifdef CONFIG_X86_32 1227 /* This bit is reserved on P4/Xeon and should be cleared */ 1228 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && 1229 (boot_cpu_data.x86 == 15)) 1230 value &= ~APIC_SPIV_FOCUS_DISABLED; 1231 else 1232 #endif 1233 value |= APIC_SPIV_FOCUS_DISABLED; 1234 value |= SPURIOUS_APIC_VECTOR; 1235 apic_write(APIC_SPIV, value); 1236 1237 /* 1238 * Set up the virtual wire mode. 1239 */ 1240 apic_write(APIC_LVT0, APIC_DM_EXTINT); 1241 value = APIC_DM_NMI; 1242 if (!lapic_is_integrated()) /* 82489DX */ 1243 value |= APIC_LVT_LEVEL_TRIGGER; 1244 apic_write(APIC_LVT1, value); 1245 } 1246 1247 static void lapic_setup_esr(void) 1248 { 1249 unsigned int oldvalue, value, maxlvt; 1250 1251 if (!lapic_is_integrated()) { 1252 pr_info("No ESR for 82489DX.\n"); 1253 return; 1254 } 1255 1256 if (apic->disable_esr) { 1257 /* 1258 * Something untraceable is creating bad interrupts on 1259 * secondary quads ... for the moment, just leave the 1260 * ESR disabled - we can't do anything useful with the 1261 * errors anyway - mbligh 1262 */ 1263 pr_info("Leaving ESR disabled.\n"); 1264 return; 1265 } 1266 1267 maxlvt = lapic_get_maxlvt(); 1268 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ 1269 apic_write(APIC_ESR, 0); 1270 oldvalue = apic_read(APIC_ESR); 1271 1272 /* enables sending errors */ 1273 value = ERROR_APIC_VECTOR; 1274 apic_write(APIC_LVTERR, value); 1275 1276 /* 1277 * spec says clear errors after enabling vector. 1278 */ 1279 if (maxlvt > 3) 1280 apic_write(APIC_ESR, 0); 1281 value = apic_read(APIC_ESR); 1282 if (value != oldvalue) 1283 apic_printk(APIC_VERBOSE, "ESR value before enabling " 1284 "vector: 0x%08x after: 0x%08x\n", 1285 oldvalue, value); 1286 } 1287 1288 /** 1289 * setup_local_APIC - setup the local APIC 1290 * 1291 * Used to setup local APIC while initializing BSP or bringin up APs. 1292 * Always called with preemption disabled. 1293 */ 1294 void setup_local_APIC(void) 1295 { 1296 int cpu = smp_processor_id(); 1297 unsigned int value, queued; 1298 int i, j, acked = 0; 1299 unsigned long long tsc = 0, ntsc; 1300 long long max_loops = cpu_khz; 1301 1302 if (cpu_has_tsc) 1303 rdtscll(tsc); 1304 1305 if (disable_apic) { 1306 disable_ioapic_support(); 1307 return; 1308 } 1309 1310 #ifdef CONFIG_X86_32 1311 /* Pound the ESR really hard over the head with a big hammer - mbligh */ 1312 if (lapic_is_integrated() && apic->disable_esr) { 1313 apic_write(APIC_ESR, 0); 1314 apic_write(APIC_ESR, 0); 1315 apic_write(APIC_ESR, 0); 1316 apic_write(APIC_ESR, 0); 1317 } 1318 #endif 1319 perf_events_lapic_init(); 1320 1321 /* 1322 * Double-check whether this APIC is really registered. 1323 * This is meaningless in clustered apic mode, so we skip it. 1324 */ 1325 BUG_ON(!apic->apic_id_registered()); 1326 1327 /* 1328 * Intel recommends to set DFR, LDR and TPR before enabling 1329 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel 1330 * document number 292116). So here it goes... 1331 */ 1332 apic->init_apic_ldr(); 1333 1334 #ifdef CONFIG_X86_32 1335 /* 1336 * APIC LDR is initialized. If logical_apicid mapping was 1337 * initialized during get_smp_config(), make sure it matches the 1338 * actual value. 1339 */ 1340 i = early_per_cpu(x86_cpu_to_logical_apicid, cpu); 1341 WARN_ON(i != BAD_APICID && i != logical_smp_processor_id()); 1342 /* always use the value from LDR */ 1343 early_per_cpu(x86_cpu_to_logical_apicid, cpu) = 1344 logical_smp_processor_id(); 1345 #endif 1346 1347 /* 1348 * Set Task Priority to 'accept all'. We never change this 1349 * later on. 1350 */ 1351 value = apic_read(APIC_TASKPRI); 1352 value &= ~APIC_TPRI_MASK; 1353 apic_write(APIC_TASKPRI, value); 1354 1355 /* 1356 * After a crash, we no longer service the interrupts and a pending 1357 * interrupt from previous kernel might still have ISR bit set. 1358 * 1359 * Most probably by now CPU has serviced that pending interrupt and 1360 * it might not have done the ack_APIC_irq() because it thought, 1361 * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it 1362 * does not clear the ISR bit and cpu thinks it has already serivced 1363 * the interrupt. Hence a vector might get locked. It was noticed 1364 * for timer irq (vector 0x31). Issue an extra EOI to clear ISR. 1365 */ 1366 do { 1367 queued = 0; 1368 for (i = APIC_ISR_NR - 1; i >= 0; i--) 1369 queued |= apic_read(APIC_IRR + i*0x10); 1370 1371 for (i = APIC_ISR_NR - 1; i >= 0; i--) { 1372 value = apic_read(APIC_ISR + i*0x10); 1373 for (j = 31; j >= 0; j--) { 1374 if (value & (1<<j)) { 1375 ack_APIC_irq(); 1376 acked++; 1377 } 1378 } 1379 } 1380 if (acked > 256) { 1381 printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n", 1382 acked); 1383 break; 1384 } 1385 if (queued) { 1386 if (cpu_has_tsc) { 1387 rdtscll(ntsc); 1388 max_loops = (cpu_khz << 10) - (ntsc - tsc); 1389 } else 1390 max_loops--; 1391 } 1392 } while (queued && max_loops > 0); 1393 WARN_ON(max_loops <= 0); 1394 1395 /* 1396 * Now that we are all set up, enable the APIC 1397 */ 1398 value = apic_read(APIC_SPIV); 1399 value &= ~APIC_VECTOR_MASK; 1400 /* 1401 * Enable APIC 1402 */ 1403 value |= APIC_SPIV_APIC_ENABLED; 1404 1405 #ifdef CONFIG_X86_32 1406 /* 1407 * Some unknown Intel IO/APIC (or APIC) errata is biting us with 1408 * certain networking cards. If high frequency interrupts are 1409 * happening on a particular IOAPIC pin, plus the IOAPIC routing 1410 * entry is masked/unmasked at a high rate as well then sooner or 1411 * later IOAPIC line gets 'stuck', no more interrupts are received 1412 * from the device. If focus CPU is disabled then the hang goes 1413 * away, oh well :-( 1414 * 1415 * [ This bug can be reproduced easily with a level-triggered 1416 * PCI Ne2000 networking cards and PII/PIII processors, dual 1417 * BX chipset. ] 1418 */ 1419 /* 1420 * Actually disabling the focus CPU check just makes the hang less 1421 * frequent as it makes the interrupt distributon model be more 1422 * like LRU than MRU (the short-term load is more even across CPUs). 1423 * See also the comment in end_level_ioapic_irq(). --macro 1424 */ 1425 1426 /* 1427 * - enable focus processor (bit==0) 1428 * - 64bit mode always use processor focus 1429 * so no need to set it 1430 */ 1431 value &= ~APIC_SPIV_FOCUS_DISABLED; 1432 #endif 1433 1434 /* 1435 * Set spurious IRQ vector 1436 */ 1437 value |= SPURIOUS_APIC_VECTOR; 1438 apic_write(APIC_SPIV, value); 1439 1440 /* 1441 * Set up LVT0, LVT1: 1442 * 1443 * set up through-local-APIC on the BP's LINT0. This is not 1444 * strictly necessary in pure symmetric-IO mode, but sometimes 1445 * we delegate interrupts to the 8259A. 1446 */ 1447 /* 1448 * TODO: set up through-local-APIC from through-I/O-APIC? --macro 1449 */ 1450 value = apic_read(APIC_LVT0) & APIC_LVT_MASKED; 1451 if (!cpu && (pic_mode || !value)) { 1452 value = APIC_DM_EXTINT; 1453 apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu); 1454 } else { 1455 value = APIC_DM_EXTINT | APIC_LVT_MASKED; 1456 apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu); 1457 } 1458 apic_write(APIC_LVT0, value); 1459 1460 /* 1461 * only the BP should see the LINT1 NMI signal, obviously. 1462 */ 1463 if (!cpu) 1464 value = APIC_DM_NMI; 1465 else 1466 value = APIC_DM_NMI | APIC_LVT_MASKED; 1467 if (!lapic_is_integrated()) /* 82489DX */ 1468 value |= APIC_LVT_LEVEL_TRIGGER; 1469 apic_write(APIC_LVT1, value); 1470 1471 #ifdef CONFIG_X86_MCE_INTEL 1472 /* Recheck CMCI information after local APIC is up on CPU #0 */ 1473 if (!cpu) 1474 cmci_recheck(); 1475 #endif 1476 } 1477 1478 void end_local_APIC_setup(void) 1479 { 1480 lapic_setup_esr(); 1481 1482 #ifdef CONFIG_X86_32 1483 { 1484 unsigned int value; 1485 /* Disable the local apic timer */ 1486 value = apic_read(APIC_LVTT); 1487 value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR); 1488 apic_write(APIC_LVTT, value); 1489 } 1490 #endif 1491 1492 apic_pm_activate(); 1493 } 1494 1495 void __init bsp_end_local_APIC_setup(void) 1496 { 1497 end_local_APIC_setup(); 1498 1499 /* 1500 * Now that local APIC setup is completed for BP, configure the fault 1501 * handling for interrupt remapping. 1502 */ 1503 irq_remap_enable_fault_handling(); 1504 1505 } 1506 1507 #ifdef CONFIG_X86_X2APIC 1508 /* 1509 * Need to disable xapic and x2apic at the same time and then enable xapic mode 1510 */ 1511 static inline void __disable_x2apic(u64 msr) 1512 { 1513 wrmsrl(MSR_IA32_APICBASE, 1514 msr & ~(X2APIC_ENABLE | XAPIC_ENABLE)); 1515 wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE); 1516 } 1517 1518 static __init void disable_x2apic(void) 1519 { 1520 u64 msr; 1521 1522 if (!cpu_has_x2apic) 1523 return; 1524 1525 rdmsrl(MSR_IA32_APICBASE, msr); 1526 if (msr & X2APIC_ENABLE) { 1527 u32 x2apic_id = read_apic_id(); 1528 1529 if (x2apic_id >= 255) 1530 panic("Cannot disable x2apic, id: %08x\n", x2apic_id); 1531 1532 pr_info("Disabling x2apic\n"); 1533 __disable_x2apic(msr); 1534 1535 if (nox2apic) { 1536 clear_cpu_cap(&cpu_data(0), X86_FEATURE_X2APIC); 1537 setup_clear_cpu_cap(X86_FEATURE_X2APIC); 1538 } 1539 1540 x2apic_disabled = 1; 1541 x2apic_mode = 0; 1542 1543 register_lapic_address(mp_lapic_addr); 1544 } 1545 } 1546 1547 void check_x2apic(void) 1548 { 1549 if (x2apic_enabled()) { 1550 pr_info("x2apic enabled by BIOS, switching to x2apic ops\n"); 1551 x2apic_preenabled = x2apic_mode = 1; 1552 } 1553 } 1554 1555 void enable_x2apic(void) 1556 { 1557 u64 msr; 1558 1559 rdmsrl(MSR_IA32_APICBASE, msr); 1560 if (x2apic_disabled) { 1561 __disable_x2apic(msr); 1562 return; 1563 } 1564 1565 if (!x2apic_mode) 1566 return; 1567 1568 if (!(msr & X2APIC_ENABLE)) { 1569 printk_once(KERN_INFO "Enabling x2apic\n"); 1570 wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE); 1571 } 1572 } 1573 #endif /* CONFIG_X86_X2APIC */ 1574 1575 int __init enable_IR(void) 1576 { 1577 #ifdef CONFIG_IRQ_REMAP 1578 if (!irq_remapping_supported()) { 1579 pr_debug("intr-remapping not supported\n"); 1580 return -1; 1581 } 1582 1583 if (!x2apic_preenabled && skip_ioapic_setup) { 1584 pr_info("Skipped enabling intr-remap because of skipping " 1585 "io-apic setup\n"); 1586 return -1; 1587 } 1588 1589 return irq_remapping_enable(); 1590 #endif 1591 return -1; 1592 } 1593 1594 void __init enable_IR_x2apic(void) 1595 { 1596 unsigned long flags; 1597 int ret, x2apic_enabled = 0; 1598 int hardware_init_ret; 1599 1600 /* Make sure irq_remap_ops are initialized */ 1601 setup_irq_remapping_ops(); 1602 1603 hardware_init_ret = irq_remapping_prepare(); 1604 if (hardware_init_ret && !x2apic_supported()) 1605 return; 1606 1607 ret = save_ioapic_entries(); 1608 if (ret) { 1609 pr_info("Saving IO-APIC state failed: %d\n", ret); 1610 return; 1611 } 1612 1613 local_irq_save(flags); 1614 legacy_pic->mask_all(); 1615 mask_ioapic_entries(); 1616 1617 if (x2apic_preenabled && nox2apic) 1618 disable_x2apic(); 1619 1620 if (hardware_init_ret) 1621 ret = -1; 1622 else 1623 ret = enable_IR(); 1624 1625 if (!x2apic_supported()) 1626 goto skip_x2apic; 1627 1628 if (ret < 0) { 1629 /* IR is required if there is APIC ID > 255 even when running 1630 * under KVM 1631 */ 1632 if (max_physical_apicid > 255 || 1633 !hypervisor_x2apic_available()) { 1634 if (x2apic_preenabled) 1635 disable_x2apic(); 1636 goto skip_x2apic; 1637 } 1638 /* 1639 * without IR all CPUs can be addressed by IOAPIC/MSI 1640 * only in physical mode 1641 */ 1642 x2apic_force_phys(); 1643 } 1644 1645 if (ret == IRQ_REMAP_XAPIC_MODE) { 1646 pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n"); 1647 goto skip_x2apic; 1648 } 1649 1650 x2apic_enabled = 1; 1651 1652 if (x2apic_supported() && !x2apic_mode) { 1653 x2apic_mode = 1; 1654 enable_x2apic(); 1655 pr_info("Enabled x2apic\n"); 1656 } 1657 1658 skip_x2apic: 1659 if (ret < 0) /* IR enabling failed */ 1660 restore_ioapic_entries(); 1661 legacy_pic->restore_mask(); 1662 local_irq_restore(flags); 1663 } 1664 1665 #ifdef CONFIG_X86_64 1666 /* 1667 * Detect and enable local APICs on non-SMP boards. 1668 * Original code written by Keir Fraser. 1669 * On AMD64 we trust the BIOS - if it says no APIC it is likely 1670 * not correctly set up (usually the APIC timer won't work etc.) 1671 */ 1672 static int __init detect_init_APIC(void) 1673 { 1674 if (!cpu_has_apic) { 1675 pr_info("No local APIC present\n"); 1676 return -1; 1677 } 1678 1679 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE; 1680 return 0; 1681 } 1682 #else 1683 1684 static int __init apic_verify(void) 1685 { 1686 u32 features, h, l; 1687 1688 /* 1689 * The APIC feature bit should now be enabled 1690 * in `cpuid' 1691 */ 1692 features = cpuid_edx(1); 1693 if (!(features & (1 << X86_FEATURE_APIC))) { 1694 pr_warning("Could not enable APIC!\n"); 1695 return -1; 1696 } 1697 set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC); 1698 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE; 1699 1700 /* The BIOS may have set up the APIC at some other address */ 1701 if (boot_cpu_data.x86 >= 6) { 1702 rdmsr(MSR_IA32_APICBASE, l, h); 1703 if (l & MSR_IA32_APICBASE_ENABLE) 1704 mp_lapic_addr = l & MSR_IA32_APICBASE_BASE; 1705 } 1706 1707 pr_info("Found and enabled local APIC!\n"); 1708 return 0; 1709 } 1710 1711 int __init apic_force_enable(unsigned long addr) 1712 { 1713 u32 h, l; 1714 1715 if (disable_apic) 1716 return -1; 1717 1718 /* 1719 * Some BIOSes disable the local APIC in the APIC_BASE 1720 * MSR. This can only be done in software for Intel P6 or later 1721 * and AMD K7 (Model > 1) or later. 1722 */ 1723 if (boot_cpu_data.x86 >= 6) { 1724 rdmsr(MSR_IA32_APICBASE, l, h); 1725 if (!(l & MSR_IA32_APICBASE_ENABLE)) { 1726 pr_info("Local APIC disabled by BIOS -- reenabling.\n"); 1727 l &= ~MSR_IA32_APICBASE_BASE; 1728 l |= MSR_IA32_APICBASE_ENABLE | addr; 1729 wrmsr(MSR_IA32_APICBASE, l, h); 1730 enabled_via_apicbase = 1; 1731 } 1732 } 1733 return apic_verify(); 1734 } 1735 1736 /* 1737 * Detect and initialize APIC 1738 */ 1739 static int __init detect_init_APIC(void) 1740 { 1741 /* Disabled by kernel option? */ 1742 if (disable_apic) 1743 return -1; 1744 1745 switch (boot_cpu_data.x86_vendor) { 1746 case X86_VENDOR_AMD: 1747 if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) || 1748 (boot_cpu_data.x86 >= 15)) 1749 break; 1750 goto no_apic; 1751 case X86_VENDOR_INTEL: 1752 if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 || 1753 (boot_cpu_data.x86 == 5 && cpu_has_apic)) 1754 break; 1755 goto no_apic; 1756 default: 1757 goto no_apic; 1758 } 1759 1760 if (!cpu_has_apic) { 1761 /* 1762 * Over-ride BIOS and try to enable the local APIC only if 1763 * "lapic" specified. 1764 */ 1765 if (!force_enable_local_apic) { 1766 pr_info("Local APIC disabled by BIOS -- " 1767 "you can enable it with \"lapic\"\n"); 1768 return -1; 1769 } 1770 if (apic_force_enable(APIC_DEFAULT_PHYS_BASE)) 1771 return -1; 1772 } else { 1773 if (apic_verify()) 1774 return -1; 1775 } 1776 1777 apic_pm_activate(); 1778 1779 return 0; 1780 1781 no_apic: 1782 pr_info("No local APIC present or hardware disabled\n"); 1783 return -1; 1784 } 1785 #endif 1786 1787 /** 1788 * init_apic_mappings - initialize APIC mappings 1789 */ 1790 void __init init_apic_mappings(void) 1791 { 1792 unsigned int new_apicid; 1793 1794 if (x2apic_mode) { 1795 boot_cpu_physical_apicid = read_apic_id(); 1796 return; 1797 } 1798 1799 /* If no local APIC can be found return early */ 1800 if (!smp_found_config && detect_init_APIC()) { 1801 /* lets NOP'ify apic operations */ 1802 pr_info("APIC: disable apic facility\n"); 1803 apic_disable(); 1804 } else { 1805 apic_phys = mp_lapic_addr; 1806 1807 /* 1808 * acpi lapic path already maps that address in 1809 * acpi_register_lapic_address() 1810 */ 1811 if (!acpi_lapic && !smp_found_config) 1812 register_lapic_address(apic_phys); 1813 } 1814 1815 /* 1816 * Fetch the APIC ID of the BSP in case we have a 1817 * default configuration (or the MP table is broken). 1818 */ 1819 new_apicid = read_apic_id(); 1820 if (boot_cpu_physical_apicid != new_apicid) { 1821 boot_cpu_physical_apicid = new_apicid; 1822 /* 1823 * yeah -- we lie about apic_version 1824 * in case if apic was disabled via boot option 1825 * but it's not a problem for SMP compiled kernel 1826 * since smp_sanity_check is prepared for such a case 1827 * and disable smp mode 1828 */ 1829 apic_version[new_apicid] = 1830 GET_APIC_VERSION(apic_read(APIC_LVR)); 1831 } 1832 } 1833 1834 void __init register_lapic_address(unsigned long address) 1835 { 1836 mp_lapic_addr = address; 1837 1838 if (!x2apic_mode) { 1839 set_fixmap_nocache(FIX_APIC_BASE, address); 1840 apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n", 1841 APIC_BASE, mp_lapic_addr); 1842 } 1843 if (boot_cpu_physical_apicid == -1U) { 1844 boot_cpu_physical_apicid = read_apic_id(); 1845 apic_version[boot_cpu_physical_apicid] = 1846 GET_APIC_VERSION(apic_read(APIC_LVR)); 1847 } 1848 } 1849 1850 /* 1851 * This initializes the IO-APIC and APIC hardware if this is 1852 * a UP kernel. 1853 */ 1854 int apic_version[MAX_LOCAL_APIC]; 1855 1856 int __init APIC_init_uniprocessor(void) 1857 { 1858 if (disable_apic) { 1859 pr_info("Apic disabled\n"); 1860 return -1; 1861 } 1862 #ifdef CONFIG_X86_64 1863 if (!cpu_has_apic) { 1864 disable_apic = 1; 1865 pr_info("Apic disabled by BIOS\n"); 1866 return -1; 1867 } 1868 #else 1869 if (!smp_found_config && !cpu_has_apic) 1870 return -1; 1871 1872 /* 1873 * Complain if the BIOS pretends there is one. 1874 */ 1875 if (!cpu_has_apic && 1876 APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) { 1877 pr_err("BIOS bug, local APIC 0x%x not detected!...\n", 1878 boot_cpu_physical_apicid); 1879 return -1; 1880 } 1881 #endif 1882 1883 default_setup_apic_routing(); 1884 1885 verify_local_APIC(); 1886 connect_bsp_APIC(); 1887 1888 #ifdef CONFIG_X86_64 1889 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid)); 1890 #else 1891 /* 1892 * Hack: In case of kdump, after a crash, kernel might be booting 1893 * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid 1894 * might be zero if read from MP tables. Get it from LAPIC. 1895 */ 1896 # ifdef CONFIG_CRASH_DUMP 1897 boot_cpu_physical_apicid = read_apic_id(); 1898 # endif 1899 #endif 1900 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); 1901 setup_local_APIC(); 1902 1903 #ifdef CONFIG_X86_IO_APIC 1904 /* 1905 * Now enable IO-APICs, actually call clear_IO_APIC 1906 * We need clear_IO_APIC before enabling error vector 1907 */ 1908 if (!skip_ioapic_setup && nr_ioapics) 1909 enable_IO_APIC(); 1910 #endif 1911 1912 bsp_end_local_APIC_setup(); 1913 1914 #ifdef CONFIG_X86_IO_APIC 1915 if (smp_found_config && !skip_ioapic_setup && nr_ioapics) 1916 setup_IO_APIC(); 1917 else { 1918 nr_ioapics = 0; 1919 } 1920 #endif 1921 1922 x86_init.timers.setup_percpu_clockev(); 1923 return 0; 1924 } 1925 1926 /* 1927 * Local APIC interrupts 1928 */ 1929 1930 /* 1931 * This interrupt should _never_ happen with our APIC/SMP architecture 1932 */ 1933 static inline void __smp_spurious_interrupt(void) 1934 { 1935 u32 v; 1936 1937 /* 1938 * Check if this really is a spurious interrupt and ACK it 1939 * if it is a vectored one. Just in case... 1940 * Spurious interrupts should not be ACKed. 1941 */ 1942 v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1)); 1943 if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f))) 1944 ack_APIC_irq(); 1945 1946 inc_irq_stat(irq_spurious_count); 1947 1948 /* see sw-dev-man vol 3, chapter 7.4.13.5 */ 1949 pr_info("spurious APIC interrupt on CPU#%d, " 1950 "should never happen.\n", smp_processor_id()); 1951 } 1952 1953 __visible void smp_spurious_interrupt(struct pt_regs *regs) 1954 { 1955 entering_irq(); 1956 __smp_spurious_interrupt(); 1957 exiting_irq(); 1958 } 1959 1960 __visible void smp_trace_spurious_interrupt(struct pt_regs *regs) 1961 { 1962 entering_irq(); 1963 trace_spurious_apic_entry(SPURIOUS_APIC_VECTOR); 1964 __smp_spurious_interrupt(); 1965 trace_spurious_apic_exit(SPURIOUS_APIC_VECTOR); 1966 exiting_irq(); 1967 } 1968 1969 /* 1970 * This interrupt should never happen with our APIC/SMP architecture 1971 */ 1972 static inline void __smp_error_interrupt(struct pt_regs *regs) 1973 { 1974 u32 v; 1975 u32 i = 0; 1976 static const char * const error_interrupt_reason[] = { 1977 "Send CS error", /* APIC Error Bit 0 */ 1978 "Receive CS error", /* APIC Error Bit 1 */ 1979 "Send accept error", /* APIC Error Bit 2 */ 1980 "Receive accept error", /* APIC Error Bit 3 */ 1981 "Redirectable IPI", /* APIC Error Bit 4 */ 1982 "Send illegal vector", /* APIC Error Bit 5 */ 1983 "Received illegal vector", /* APIC Error Bit 6 */ 1984 "Illegal register address", /* APIC Error Bit 7 */ 1985 }; 1986 1987 /* First tickle the hardware, only then report what went on. -- REW */ 1988 if (lapic_get_maxlvt() > 3) /* Due to the Pentium erratum 3AP. */ 1989 apic_write(APIC_ESR, 0); 1990 v = apic_read(APIC_ESR); 1991 ack_APIC_irq(); 1992 atomic_inc(&irq_err_count); 1993 1994 apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x", 1995 smp_processor_id(), v); 1996 1997 v &= 0xff; 1998 while (v) { 1999 if (v & 0x1) 2000 apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]); 2001 i++; 2002 v >>= 1; 2003 } 2004 2005 apic_printk(APIC_DEBUG, KERN_CONT "\n"); 2006 2007 } 2008 2009 __visible void smp_error_interrupt(struct pt_regs *regs) 2010 { 2011 entering_irq(); 2012 __smp_error_interrupt(regs); 2013 exiting_irq(); 2014 } 2015 2016 __visible void smp_trace_error_interrupt(struct pt_regs *regs) 2017 { 2018 entering_irq(); 2019 trace_error_apic_entry(ERROR_APIC_VECTOR); 2020 __smp_error_interrupt(regs); 2021 trace_error_apic_exit(ERROR_APIC_VECTOR); 2022 exiting_irq(); 2023 } 2024 2025 /** 2026 * connect_bsp_APIC - attach the APIC to the interrupt system 2027 */ 2028 void __init connect_bsp_APIC(void) 2029 { 2030 #ifdef CONFIG_X86_32 2031 if (pic_mode) { 2032 /* 2033 * Do not trust the local APIC being empty at bootup. 2034 */ 2035 clear_local_APIC(); 2036 /* 2037 * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's 2038 * local APIC to INT and NMI lines. 2039 */ 2040 apic_printk(APIC_VERBOSE, "leaving PIC mode, " 2041 "enabling APIC mode.\n"); 2042 imcr_pic_to_apic(); 2043 } 2044 #endif 2045 } 2046 2047 /** 2048 * disconnect_bsp_APIC - detach the APIC from the interrupt system 2049 * @virt_wire_setup: indicates, whether virtual wire mode is selected 2050 * 2051 * Virtual wire mode is necessary to deliver legacy interrupts even when the 2052 * APIC is disabled. 2053 */ 2054 void disconnect_bsp_APIC(int virt_wire_setup) 2055 { 2056 unsigned int value; 2057 2058 #ifdef CONFIG_X86_32 2059 if (pic_mode) { 2060 /* 2061 * Put the board back into PIC mode (has an effect only on 2062 * certain older boards). Note that APIC interrupts, including 2063 * IPIs, won't work beyond this point! The only exception are 2064 * INIT IPIs. 2065 */ 2066 apic_printk(APIC_VERBOSE, "disabling APIC mode, " 2067 "entering PIC mode.\n"); 2068 imcr_apic_to_pic(); 2069 return; 2070 } 2071 #endif 2072 2073 /* Go back to Virtual Wire compatibility mode */ 2074 2075 /* For the spurious interrupt use vector F, and enable it */ 2076 value = apic_read(APIC_SPIV); 2077 value &= ~APIC_VECTOR_MASK; 2078 value |= APIC_SPIV_APIC_ENABLED; 2079 value |= 0xf; 2080 apic_write(APIC_SPIV, value); 2081 2082 if (!virt_wire_setup) { 2083 /* 2084 * For LVT0 make it edge triggered, active high, 2085 * external and enabled 2086 */ 2087 value = apic_read(APIC_LVT0); 2088 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING | 2089 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR | 2090 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED); 2091 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING; 2092 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT); 2093 apic_write(APIC_LVT0, value); 2094 } else { 2095 /* Disable LVT0 */ 2096 apic_write(APIC_LVT0, APIC_LVT_MASKED); 2097 } 2098 2099 /* 2100 * For LVT1 make it edge triggered, active high, 2101 * nmi and enabled 2102 */ 2103 value = apic_read(APIC_LVT1); 2104 value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING | 2105 APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR | 2106 APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED); 2107 value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING; 2108 value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI); 2109 apic_write(APIC_LVT1, value); 2110 } 2111 2112 int generic_processor_info(int apicid, int version) 2113 { 2114 int cpu, max = nr_cpu_ids; 2115 bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid, 2116 phys_cpu_present_map); 2117 2118 /* 2119 * boot_cpu_physical_apicid is designed to have the apicid 2120 * returned by read_apic_id(), i.e, the apicid of the 2121 * currently booting-up processor. However, on some platforms, 2122 * it is temporarily modified by the apicid reported as BSP 2123 * through MP table. Concretely: 2124 * 2125 * - arch/x86/kernel/mpparse.c: MP_processor_info() 2126 * - arch/x86/mm/amdtopology.c: amd_numa_init() 2127 * 2128 * This function is executed with the modified 2129 * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel 2130 * parameter doesn't work to disable APs on kdump 2nd kernel. 2131 * 2132 * Since fixing handling of boot_cpu_physical_apicid requires 2133 * another discussion and tests on each platform, we leave it 2134 * for now and here we use read_apic_id() directly in this 2135 * function, generic_processor_info(). 2136 */ 2137 if (disabled_cpu_apicid != BAD_APICID && 2138 disabled_cpu_apicid != read_apic_id() && 2139 disabled_cpu_apicid == apicid) { 2140 int thiscpu = num_processors + disabled_cpus; 2141 2142 pr_warning("APIC: Disabling requested cpu." 2143 " Processor %d/0x%x ignored.\n", 2144 thiscpu, apicid); 2145 2146 disabled_cpus++; 2147 return -ENODEV; 2148 } 2149 2150 /* 2151 * If boot cpu has not been detected yet, then only allow upto 2152 * nr_cpu_ids - 1 processors and keep one slot free for boot cpu 2153 */ 2154 if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 && 2155 apicid != boot_cpu_physical_apicid) { 2156 int thiscpu = max + disabled_cpus - 1; 2157 2158 pr_warning( 2159 "ACPI: NR_CPUS/possible_cpus limit of %i almost" 2160 " reached. Keeping one slot for boot cpu." 2161 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid); 2162 2163 disabled_cpus++; 2164 return -ENODEV; 2165 } 2166 2167 if (num_processors >= nr_cpu_ids) { 2168 int thiscpu = max + disabled_cpus; 2169 2170 pr_warning( 2171 "ACPI: NR_CPUS/possible_cpus limit of %i reached." 2172 " Processor %d/0x%x ignored.\n", max, thiscpu, apicid); 2173 2174 disabled_cpus++; 2175 return -EINVAL; 2176 } 2177 2178 num_processors++; 2179 if (apicid == boot_cpu_physical_apicid) { 2180 /* 2181 * x86_bios_cpu_apicid is required to have processors listed 2182 * in same order as logical cpu numbers. Hence the first 2183 * entry is BSP, and so on. 2184 * boot_cpu_init() already hold bit 0 in cpu_present_mask 2185 * for BSP. 2186 */ 2187 cpu = 0; 2188 } else 2189 cpu = cpumask_next_zero(-1, cpu_present_mask); 2190 2191 /* 2192 * Validate version 2193 */ 2194 if (version == 0x0) { 2195 pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n", 2196 cpu, apicid); 2197 version = 0x10; 2198 } 2199 apic_version[apicid] = version; 2200 2201 if (version != apic_version[boot_cpu_physical_apicid]) { 2202 pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n", 2203 apic_version[boot_cpu_physical_apicid], cpu, version); 2204 } 2205 2206 physid_set(apicid, phys_cpu_present_map); 2207 if (apicid > max_physical_apicid) 2208 max_physical_apicid = apicid; 2209 2210 #if defined(CONFIG_SMP) || defined(CONFIG_X86_64) 2211 early_per_cpu(x86_cpu_to_apicid, cpu) = apicid; 2212 early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid; 2213 #endif 2214 #ifdef CONFIG_X86_32 2215 early_per_cpu(x86_cpu_to_logical_apicid, cpu) = 2216 apic->x86_32_early_logical_apicid(cpu); 2217 #endif 2218 set_cpu_possible(cpu, true); 2219 set_cpu_present(cpu, true); 2220 2221 return cpu; 2222 } 2223 2224 int hard_smp_processor_id(void) 2225 { 2226 return read_apic_id(); 2227 } 2228 2229 void default_init_apic_ldr(void) 2230 { 2231 unsigned long val; 2232 2233 apic_write(APIC_DFR, APIC_DFR_VALUE); 2234 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK; 2235 val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id()); 2236 apic_write(APIC_LDR, val); 2237 } 2238 2239 int default_cpu_mask_to_apicid_and(const struct cpumask *cpumask, 2240 const struct cpumask *andmask, 2241 unsigned int *apicid) 2242 { 2243 unsigned int cpu; 2244 2245 for_each_cpu_and(cpu, cpumask, andmask) { 2246 if (cpumask_test_cpu(cpu, cpu_online_mask)) 2247 break; 2248 } 2249 2250 if (likely(cpu < nr_cpu_ids)) { 2251 *apicid = per_cpu(x86_cpu_to_apicid, cpu); 2252 return 0; 2253 } 2254 2255 return -EINVAL; 2256 } 2257 2258 /* 2259 * Override the generic EOI implementation with an optimized version. 2260 * Only called during early boot when only one CPU is active and with 2261 * interrupts disabled, so we know this does not race with actual APIC driver 2262 * use. 2263 */ 2264 void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v)) 2265 { 2266 struct apic **drv; 2267 2268 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 2269 /* Should happen once for each apic */ 2270 WARN_ON((*drv)->eoi_write == eoi_write); 2271 (*drv)->eoi_write = eoi_write; 2272 } 2273 } 2274 2275 /* 2276 * Power management 2277 */ 2278 #ifdef CONFIG_PM 2279 2280 static struct { 2281 /* 2282 * 'active' is true if the local APIC was enabled by us and 2283 * not the BIOS; this signifies that we are also responsible 2284 * for disabling it before entering apm/acpi suspend 2285 */ 2286 int active; 2287 /* r/w apic fields */ 2288 unsigned int apic_id; 2289 unsigned int apic_taskpri; 2290 unsigned int apic_ldr; 2291 unsigned int apic_dfr; 2292 unsigned int apic_spiv; 2293 unsigned int apic_lvtt; 2294 unsigned int apic_lvtpc; 2295 unsigned int apic_lvt0; 2296 unsigned int apic_lvt1; 2297 unsigned int apic_lvterr; 2298 unsigned int apic_tmict; 2299 unsigned int apic_tdcr; 2300 unsigned int apic_thmr; 2301 } apic_pm_state; 2302 2303 static int lapic_suspend(void) 2304 { 2305 unsigned long flags; 2306 int maxlvt; 2307 2308 if (!apic_pm_state.active) 2309 return 0; 2310 2311 maxlvt = lapic_get_maxlvt(); 2312 2313 apic_pm_state.apic_id = apic_read(APIC_ID); 2314 apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI); 2315 apic_pm_state.apic_ldr = apic_read(APIC_LDR); 2316 apic_pm_state.apic_dfr = apic_read(APIC_DFR); 2317 apic_pm_state.apic_spiv = apic_read(APIC_SPIV); 2318 apic_pm_state.apic_lvtt = apic_read(APIC_LVTT); 2319 if (maxlvt >= 4) 2320 apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC); 2321 apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0); 2322 apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1); 2323 apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR); 2324 apic_pm_state.apic_tmict = apic_read(APIC_TMICT); 2325 apic_pm_state.apic_tdcr = apic_read(APIC_TDCR); 2326 #ifdef CONFIG_X86_THERMAL_VECTOR 2327 if (maxlvt >= 5) 2328 apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR); 2329 #endif 2330 2331 local_irq_save(flags); 2332 disable_local_APIC(); 2333 2334 irq_remapping_disable(); 2335 2336 local_irq_restore(flags); 2337 return 0; 2338 } 2339 2340 static void lapic_resume(void) 2341 { 2342 unsigned int l, h; 2343 unsigned long flags; 2344 int maxlvt; 2345 2346 if (!apic_pm_state.active) 2347 return; 2348 2349 local_irq_save(flags); 2350 2351 /* 2352 * IO-APIC and PIC have their own resume routines. 2353 * We just mask them here to make sure the interrupt 2354 * subsystem is completely quiet while we enable x2apic 2355 * and interrupt-remapping. 2356 */ 2357 mask_ioapic_entries(); 2358 legacy_pic->mask_all(); 2359 2360 if (x2apic_mode) 2361 enable_x2apic(); 2362 else { 2363 /* 2364 * Make sure the APICBASE points to the right address 2365 * 2366 * FIXME! This will be wrong if we ever support suspend on 2367 * SMP! We'll need to do this as part of the CPU restore! 2368 */ 2369 if (boot_cpu_data.x86 >= 6) { 2370 rdmsr(MSR_IA32_APICBASE, l, h); 2371 l &= ~MSR_IA32_APICBASE_BASE; 2372 l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr; 2373 wrmsr(MSR_IA32_APICBASE, l, h); 2374 } 2375 } 2376 2377 maxlvt = lapic_get_maxlvt(); 2378 apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED); 2379 apic_write(APIC_ID, apic_pm_state.apic_id); 2380 apic_write(APIC_DFR, apic_pm_state.apic_dfr); 2381 apic_write(APIC_LDR, apic_pm_state.apic_ldr); 2382 apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri); 2383 apic_write(APIC_SPIV, apic_pm_state.apic_spiv); 2384 apic_write(APIC_LVT0, apic_pm_state.apic_lvt0); 2385 apic_write(APIC_LVT1, apic_pm_state.apic_lvt1); 2386 #if defined(CONFIG_X86_MCE_INTEL) 2387 if (maxlvt >= 5) 2388 apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr); 2389 #endif 2390 if (maxlvt >= 4) 2391 apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc); 2392 apic_write(APIC_LVTT, apic_pm_state.apic_lvtt); 2393 apic_write(APIC_TDCR, apic_pm_state.apic_tdcr); 2394 apic_write(APIC_TMICT, apic_pm_state.apic_tmict); 2395 apic_write(APIC_ESR, 0); 2396 apic_read(APIC_ESR); 2397 apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr); 2398 apic_write(APIC_ESR, 0); 2399 apic_read(APIC_ESR); 2400 2401 irq_remapping_reenable(x2apic_mode); 2402 2403 local_irq_restore(flags); 2404 } 2405 2406 /* 2407 * This device has no shutdown method - fully functioning local APICs 2408 * are needed on every CPU up until machine_halt/restart/poweroff. 2409 */ 2410 2411 static struct syscore_ops lapic_syscore_ops = { 2412 .resume = lapic_resume, 2413 .suspend = lapic_suspend, 2414 }; 2415 2416 static void apic_pm_activate(void) 2417 { 2418 apic_pm_state.active = 1; 2419 } 2420 2421 static int __init init_lapic_sysfs(void) 2422 { 2423 /* XXX: remove suspend/resume procs if !apic_pm_state.active? */ 2424 if (cpu_has_apic) 2425 register_syscore_ops(&lapic_syscore_ops); 2426 2427 return 0; 2428 } 2429 2430 /* local apic needs to resume before other devices access its registers. */ 2431 core_initcall(init_lapic_sysfs); 2432 2433 #else /* CONFIG_PM */ 2434 2435 static void apic_pm_activate(void) { } 2436 2437 #endif /* CONFIG_PM */ 2438 2439 #ifdef CONFIG_X86_64 2440 2441 static int multi_checked; 2442 static int multi; 2443 2444 static int set_multi(const struct dmi_system_id *d) 2445 { 2446 if (multi) 2447 return 0; 2448 pr_info("APIC: %s detected, Multi Chassis\n", d->ident); 2449 multi = 1; 2450 return 0; 2451 } 2452 2453 static const struct dmi_system_id multi_dmi_table[] = { 2454 { 2455 .callback = set_multi, 2456 .ident = "IBM System Summit2", 2457 .matches = { 2458 DMI_MATCH(DMI_SYS_VENDOR, "IBM"), 2459 DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"), 2460 }, 2461 }, 2462 {} 2463 }; 2464 2465 static void dmi_check_multi(void) 2466 { 2467 if (multi_checked) 2468 return; 2469 2470 dmi_check_system(multi_dmi_table); 2471 multi_checked = 1; 2472 } 2473 2474 /* 2475 * apic_is_clustered_box() -- Check if we can expect good TSC 2476 * 2477 * Thus far, the major user of this is IBM's Summit2 series: 2478 * Clustered boxes may have unsynced TSC problems if they are 2479 * multi-chassis. 2480 * Use DMI to check them 2481 */ 2482 int apic_is_clustered_box(void) 2483 { 2484 dmi_check_multi(); 2485 return multi; 2486 } 2487 #endif 2488 2489 /* 2490 * APIC command line parameters 2491 */ 2492 static int __init setup_disableapic(char *arg) 2493 { 2494 disable_apic = 1; 2495 setup_clear_cpu_cap(X86_FEATURE_APIC); 2496 return 0; 2497 } 2498 early_param("disableapic", setup_disableapic); 2499 2500 /* same as disableapic, for compatibility */ 2501 static int __init setup_nolapic(char *arg) 2502 { 2503 return setup_disableapic(arg); 2504 } 2505 early_param("nolapic", setup_nolapic); 2506 2507 static int __init parse_lapic_timer_c2_ok(char *arg) 2508 { 2509 local_apic_timer_c2_ok = 1; 2510 return 0; 2511 } 2512 early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok); 2513 2514 static int __init parse_disable_apic_timer(char *arg) 2515 { 2516 disable_apic_timer = 1; 2517 return 0; 2518 } 2519 early_param("noapictimer", parse_disable_apic_timer); 2520 2521 static int __init parse_nolapic_timer(char *arg) 2522 { 2523 disable_apic_timer = 1; 2524 return 0; 2525 } 2526 early_param("nolapic_timer", parse_nolapic_timer); 2527 2528 static int __init apic_set_verbosity(char *arg) 2529 { 2530 if (!arg) { 2531 #ifdef CONFIG_X86_64 2532 skip_ioapic_setup = 0; 2533 return 0; 2534 #endif 2535 return -EINVAL; 2536 } 2537 2538 if (strcmp("debug", arg) == 0) 2539 apic_verbosity = APIC_DEBUG; 2540 else if (strcmp("verbose", arg) == 0) 2541 apic_verbosity = APIC_VERBOSE; 2542 else { 2543 pr_warning("APIC Verbosity level %s not recognised" 2544 " use apic=verbose or apic=debug\n", arg); 2545 return -EINVAL; 2546 } 2547 2548 return 0; 2549 } 2550 early_param("apic", apic_set_verbosity); 2551 2552 static int __init lapic_insert_resource(void) 2553 { 2554 if (!apic_phys) 2555 return -1; 2556 2557 /* Put local APIC into the resource map. */ 2558 lapic_resource.start = apic_phys; 2559 lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1; 2560 insert_resource(&iomem_resource, &lapic_resource); 2561 2562 return 0; 2563 } 2564 2565 /* 2566 * need call insert after e820_reserve_resources() 2567 * that is using request_resource 2568 */ 2569 late_initcall(lapic_insert_resource); 2570 2571 static int __init apic_set_disabled_cpu_apicid(char *arg) 2572 { 2573 if (!arg || !get_option(&arg, &disabled_cpu_apicid)) 2574 return -EINVAL; 2575 2576 return 0; 2577 } 2578 early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid); 2579