arch/x86/kernel/cpu/mce/therm_throt.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Thermal throttle event support code (such as syslog messaging and rate
   4  * limiting) that was factored out from x86_64 (mce_intel.c) and i386 (p4.c).
   5  *
   6  * This allows consistent reporting of CPU thermal throttle events.
   7  *
   8  * Maintains a counter in /sys that keeps track of the number of thermal
   9  * events, such that the user knows how bad the thermal problem might be
  10  * (since the logging to syslog is rate limited).
  11  *
  12  * Author: Dmitriy Zavin (dmitriyz@google.com)
  13  *
  14  * Credits: Adapted from Zwane Mwaikambo's original code in mce_intel.c.
  15  *          Inspired by Ross Biro's and Al Borchers' counter code.
  16  */
  17 #include <linux/interrupt.h>
  18 #include <linux/notifier.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/kernel.h>
  21 #include <linux/percpu.h>
  22 #include <linux/export.h>
  23 #include <linux/types.h>
  24 #include <linux/init.h>
  25 #include <linux/smp.h>
  26 #include <linux/cpu.h>
  27
  28 #include <asm/processor.h>
  29 #include <asm/traps.h>
  30 #include <asm/apic.h>
  31 #include <asm/mce.h>
  32 #include <asm/msr.h>
  33 #include <asm/trace/irq_vectors.h>
  34
  35 #include "internal.h"
  36
  37 /* How long to wait between reporting thermal events */
  38 #define CHECK_INTERVAL          (300 * HZ)
  39
  40 #define THERMAL_THROTTLING_EVENT        0
  41 #define POWER_LIMIT_EVENT               1
  42
  43 /**
  44  * struct _thermal_state - Represent the current thermal event state
  45  * @next_check:                 Stores the next timestamp, when it is allowed
  46  *                              to log the next warning message.
  47  * @last_interrupt_time:        Stores the timestamp for the last threshold
  48  *                              high event.
  49  * @therm_work:                 Delayed workqueue structure
  50  * @count:                      Stores the current running count for thermal
  51  *                              or power threshold interrupts.
  52  * @last_count:                 Stores the previous running count for thermal
  53  *                              or power threshold interrupts.
  54  * @max_time_ms:                This shows the maximum amount of time CPU was
  55  *                              in throttled state for a single thermal
  56  *                              threshold high to low state.
  57  * @total_time_ms:              This is a cumulative time during which CPU was
  58  *                              in the throttled state.
  59  * @rate_control_active:        Set when a throttling message is logged.
  60  *                              This is used for the purpose of rate-control.
  61  * @new_event:                  Stores the last high/low status of the
  62  *                              THERM_STATUS_PROCHOT or
  63  *                              THERM_STATUS_POWER_LIMIT.
  64  * @level:                      Stores whether this _thermal_state instance is
  65  *                              for a CORE level or for PACKAGE level.
  66  * @sample_index:               Index for storing the next sample in the buffer
  67  *                              temp_samples[].
  68  * @sample_count:               Total number of samples collected in the buffer
  69  *                              temp_samples[].
  70  * @average:                    The last moving average of temperature samples
  71  * @baseline_temp:              Temperature at which thermal threshold high
  72  *                              interrupt was generated.
  73  * @temp_samples:               Storage for temperature samples to calculate
  74  *                              moving average.
  75  *
  76  * This structure is used to represent data related to thermal state for a CPU.
  77  * There is a separate storage for core and package level for each CPU.
  78  */
  79 struct _thermal_state {
  80         u64                     next_check;
  81         u64                     last_interrupt_time;
  82         struct delayed_work     therm_work;
  83         unsigned long           count;
  84         unsigned long           last_count;
  85         unsigned long           max_time_ms;
  86         unsigned long           total_time_ms;
  87         bool                    rate_control_active;
  88         bool                    new_event;
  89         u8                      level;
  90         u8                      sample_index;
  91         u8                      sample_count;
  92         u8                      average;
  93         u8                      baseline_temp;
  94         u8                      temp_samples[3];
  95 };
  96
  97 struct thermal_state {
  98         struct _thermal_state core_throttle;
  99         struct _thermal_state core_power_limit;
 100         struct _thermal_state package_throttle;
 101         struct _thermal_state package_power_limit;
 102         struct _thermal_state core_thresh0;
 103         struct _thermal_state core_thresh1;
 104         struct _thermal_state pkg_thresh0;
 105         struct _thermal_state pkg_thresh1;
 106 };
 107
 108 /* Callback to handle core threshold interrupts */
 109 int (*platform_thermal_notify)(__u64 msr_val);
 110 EXPORT_SYMBOL(platform_thermal_notify);
 111
 112 /* Callback to handle core package threshold_interrupts */
 113 int (*platform_thermal_package_notify)(__u64 msr_val);
 114 EXPORT_SYMBOL_GPL(platform_thermal_package_notify);
 115
 116 /* Callback support of rate control, return true, if
 117  * callback has rate control */
 118 bool (*platform_thermal_package_rate_control)(void);
 119 EXPORT_SYMBOL_GPL(platform_thermal_package_rate_control);
 120
 121
 122 static DEFINE_PER_CPU(struct thermal_state, thermal_state);
 123
 124 static atomic_t therm_throt_en  = ATOMIC_INIT(0);
 125
 126 static u32 lvtthmr_init __read_mostly;
 127
 128 #ifdef CONFIG_SYSFS
 129 #define define_therm_throt_device_one_ro(_name)                         \
 130         static DEVICE_ATTR(_name, 0444,                                 \
 131                            therm_throt_device_show_##_name,             \
 132                                    NULL)                                \
 133
 134 #define define_therm_throt_device_show_func(event, name)                \
 135                                                                         \
 136 static ssize_t therm_throt_device_show_##event##_##name(                \
 137                         struct device *dev,                             \
 138                         struct device_attribute *attr,                  \
 139                         char *buf)                                      \
 140 {                                                                       \
 141         unsigned int cpu = dev->id;                                     \
 142         ssize_t ret;                                                    \
 143                                                                         \
 144         preempt_disable();      /* CPU hotplug */                       \
 145         if (cpu_online(cpu)) {                                          \
 146                 ret = sprintf(buf, "%lu\n",                             \
 147                               per_cpu(thermal_state, cpu).event.name);  \
 148         } else                                                          \
 149                 ret = 0;                                                \
 150         preempt_enable();                                               \
 151                                                                         \
 152         return ret;                                                     \
 153 }
 154
 155 define_therm_throt_device_show_func(core_throttle, count);
 156 define_therm_throt_device_one_ro(core_throttle_count);
 157
 158 define_therm_throt_device_show_func(core_power_limit, count);
 159 define_therm_throt_device_one_ro(core_power_limit_count);
 160
 161 define_therm_throt_device_show_func(package_throttle, count);
 162 define_therm_throt_device_one_ro(package_throttle_count);
 163
 164 define_therm_throt_device_show_func(package_power_limit, count);
 165 define_therm_throt_device_one_ro(package_power_limit_count);
 166
 167 define_therm_throt_device_show_func(core_throttle, max_time_ms);
 168 define_therm_throt_device_one_ro(core_throttle_max_time_ms);
 169
 170 define_therm_throt_device_show_func(package_throttle, max_time_ms);
 171 define_therm_throt_device_one_ro(package_throttle_max_time_ms);
 172
 173 define_therm_throt_device_show_func(core_throttle, total_time_ms);
 174 define_therm_throt_device_one_ro(core_throttle_total_time_ms);
 175
 176 define_therm_throt_device_show_func(package_throttle, total_time_ms);
 177 define_therm_throt_device_one_ro(package_throttle_total_time_ms);
 178
 179 static struct attribute *thermal_throttle_attrs[] = {
 180         &dev_attr_core_throttle_count.attr,
 181         &dev_attr_core_throttle_max_time_ms.attr,
 182         &dev_attr_core_throttle_total_time_ms.attr,
 183         NULL
 184 };
 185
 186 static const struct attribute_group thermal_attr_group = {
 187         .attrs  = thermal_throttle_attrs,
 188         .name   = "thermal_throttle"
 189 };
 190 #endif /* CONFIG_SYSFS */
 191
 192 #define CORE_LEVEL      0
 193 #define PACKAGE_LEVEL   1
 194
 195 #define THERM_THROT_POLL_INTERVAL       HZ
 196 #define THERM_STATUS_PROCHOT_LOG        BIT(1)
 197
 198 static void clear_therm_status_log(int level)
 199 {
 200         int msr;
 201         u64 msr_val;
 202
 203         if (level == CORE_LEVEL)
 204                 msr = MSR_IA32_THERM_STATUS;
 205         else
 206                 msr = MSR_IA32_PACKAGE_THERM_STATUS;
 207
 208         rdmsrl(msr, msr_val);
 209         wrmsrl(msr, msr_val & ~THERM_STATUS_PROCHOT_LOG);
 210 }
 211
 212 static void get_therm_status(int level, bool *proc_hot, u8 *temp)
 213 {
 214         int msr;
 215         u64 msr_val;
 216
 217         if (level == CORE_LEVEL)
 218                 msr = MSR_IA32_THERM_STATUS;
 219         else
 220                 msr = MSR_IA32_PACKAGE_THERM_STATUS;
 221
 222         rdmsrl(msr, msr_val);
 223         if (msr_val & THERM_STATUS_PROCHOT_LOG)
 224                 *proc_hot = true;
 225         else
 226                 *proc_hot = false;
 227
 228         *temp = (msr_val >> 16) & 0x7F;
 229 }
 230
 231 static void throttle_active_work(struct work_struct *work)
 232 {
 233         struct _thermal_state *state = container_of(to_delayed_work(work),
 234                                                 struct _thermal_state, therm_work);
 235         unsigned int i, avg, this_cpu = smp_processor_id();
 236         u64 now = get_jiffies_64();
 237         bool hot;
 238         u8 temp;
 239
 240         get_therm_status(state->level, &hot, &temp);
 241         /* temperature value is offset from the max so lesser means hotter */
 242         if (!hot && temp > state->baseline_temp) {
 243                 if (state->rate_control_active)
 244                         pr_info("CPU%d: %s temperature/speed normal (total events = %lu)\n",
 245                                 this_cpu,
 246                                 state->level == CORE_LEVEL ? "Core" : "Package",
 247                                 state->count);
 248
 249                 state->rate_control_active = false;
 250                 return;
 251         }
 252
 253         if (time_before64(now, state->next_check) &&
 254                           state->rate_control_active)
 255                 goto re_arm;
 256
 257         state->next_check = now + CHECK_INTERVAL;
 258
 259         if (state->count != state->last_count) {
 260                 /* There was one new thermal interrupt */
 261                 state->last_count = state->count;
 262                 state->average = 0;
 263                 state->sample_count = 0;
 264                 state->sample_index = 0;
 265         }
 266
 267         state->temp_samples[state->sample_index] = temp;
 268         state->sample_count++;
 269         state->sample_index = (state->sample_index + 1) % ARRAY_SIZE(state->temp_samples);
 270         if (state->sample_count < ARRAY_SIZE(state->temp_samples))
 271                 goto re_arm;
 272
 273         avg = 0;
 274         for (i = 0; i < ARRAY_SIZE(state->temp_samples); ++i)
 275                 avg += state->temp_samples[i];
 276
 277         avg /= ARRAY_SIZE(state->temp_samples);
 278
 279         if (state->average > avg) {
 280                 pr_warn("CPU%d: %s temperature is above threshold, cpu clock is throttled (total events = %lu)\n",
 281                         this_cpu,
 282                         state->level == CORE_LEVEL ? "Core" : "Package",
 283                         state->count);
 284                 state->rate_control_active = true;
 285         }
 286
 287         state->average = avg;
 288
 289 re_arm:
 290         clear_therm_status_log(state->level);
 291         schedule_delayed_work_on(this_cpu, &state->therm_work, THERM_THROT_POLL_INTERVAL);
 292 }
 293
 294 /***
 295  * therm_throt_process - Process thermal throttling event from interrupt
 296  * @curr: Whether the condition is current or not (boolean), since the
 297  *        thermal interrupt normally gets called both when the thermal
 298  *        event begins and once the event has ended.
 299  *
 300  * This function is called by the thermal interrupt after the
 301  * IRQ has been acknowledged.
 302  *
 303  * It will take care of rate limiting and printing messages to the syslog.
 304  */
 305 static void therm_throt_process(bool new_event, int event, int level)
 306 {
 307         struct _thermal_state *state;
 308         unsigned int this_cpu = smp_processor_id();
 309         bool old_event;
 310         u64 now;
 311         struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
 312
 313         now = get_jiffies_64();
 314         if (level == CORE_LEVEL) {
 315                 if (event == THERMAL_THROTTLING_EVENT)
 316                         state = &pstate->core_throttle;
 317                 else if (event == POWER_LIMIT_EVENT)
 318                         state = &pstate->core_power_limit;
 319                 else
 320                         return;
 321         } else if (level == PACKAGE_LEVEL) {
 322                 if (event == THERMAL_THROTTLING_EVENT)
 323                         state = &pstate->package_throttle;
 324                 else if (event == POWER_LIMIT_EVENT)
 325                         state = &pstate->package_power_limit;
 326                 else
 327                         return;
 328         } else
 329                 return;
 330
 331         old_event = state->new_event;
 332         state->new_event = new_event;
 333
 334         if (new_event)
 335                 state->count++;
 336
 337         if (event != THERMAL_THROTTLING_EVENT)
 338                 return;
 339
 340         if (new_event && !state->last_interrupt_time) {
 341                 bool hot;
 342                 u8 temp;
 343
 344                 get_therm_status(state->level, &hot, &temp);
 345                 /*
 346                  * Ignore short temperature spike as the system is not close
 347                  * to PROCHOT. 10C offset is large enough to ignore. It is
 348                  * already dropped from the high threshold temperature.
 349                  */
 350                 if (temp > 10)
 351                         return;
 352
 353                 state->baseline_temp = temp;
 354                 state->last_interrupt_time = now;
 355                 schedule_delayed_work_on(this_cpu, &state->therm_work, THERM_THROT_POLL_INTERVAL);
 356         } else if (old_event && state->last_interrupt_time) {
 357                 unsigned long throttle_time;
 358
 359                 throttle_time = jiffies_delta_to_msecs(now - state->last_interrupt_time);
 360                 if (throttle_time > state->max_time_ms)
 361                         state->max_time_ms = throttle_time;
 362                 state->total_time_ms += throttle_time;
 363                 state->last_interrupt_time = 0;
 364         }
 365 }
 366
 367 static int thresh_event_valid(int level, int event)
 368 {
 369         struct _thermal_state *state;
 370         unsigned int this_cpu = smp_processor_id();
 371         struct thermal_state *pstate = &per_cpu(thermal_state, this_cpu);
 372         u64 now = get_jiffies_64();
 373
 374         if (level == PACKAGE_LEVEL)
 375                 state = (event == 0) ? &pstate->pkg_thresh0 :
 376                                                 &pstate->pkg_thresh1;
 377         else
 378                 state = (event == 0) ? &pstate->core_thresh0 :
 379                                                 &pstate->core_thresh1;
 380
 381         if (time_before64(now, state->next_check))
 382                 return 0;
 383
 384         state->next_check = now + CHECK_INTERVAL;
 385
 386         return 1;
 387 }
 388
 389 static bool int_pln_enable;
 390 static int __init int_pln_enable_setup(char *s)
 391 {
 392         int_pln_enable = true;
 393
 394         return 1;
 395 }
 396 __setup("int_pln_enable", int_pln_enable_setup);
 397
 398 #ifdef CONFIG_SYSFS
 399 /* Add/Remove thermal_throttle interface for CPU device: */
 400 static int thermal_throttle_add_dev(struct device *dev, unsigned int cpu)
 401 {
 402         int err;
 403         struct cpuinfo_x86 *c = &cpu_data(cpu);
 404
 405         err = sysfs_create_group(&dev->kobj, &thermal_attr_group);
 406         if (err)
 407                 return err;
 408
 409         if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable) {
 410                 err = sysfs_add_file_to_group(&dev->kobj,
 411                                               &dev_attr_core_power_limit_count.attr,
 412                                               thermal_attr_group.name);
 413                 if (err)
 414                         goto del_group;
 415         }
 416
 417         if (cpu_has(c, X86_FEATURE_PTS)) {
 418                 err = sysfs_add_file_to_group(&dev->kobj,
 419                                               &dev_attr_package_throttle_count.attr,
 420                                               thermal_attr_group.name);
 421                 if (err)
 422                         goto del_group;
 423
 424                 err = sysfs_add_file_to_group(&dev->kobj,
 425                                               &dev_attr_package_throttle_max_time_ms.attr,
 426                                               thermal_attr_group.name);
 427                 if (err)
 428                         goto del_group;
 429
 430                 err = sysfs_add_file_to_group(&dev->kobj,
 431                                               &dev_attr_package_throttle_total_time_ms.attr,
 432                                               thermal_attr_group.name);
 433                 if (err)
 434                         goto del_group;
 435
 436                 if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable) {
 437                         err = sysfs_add_file_to_group(&dev->kobj,
 438                                         &dev_attr_package_power_limit_count.attr,
 439                                         thermal_attr_group.name);
 440                         if (err)
 441                                 goto del_group;
 442                 }
 443         }
 444
 445         return 0;
 446
 447 del_group:
 448         sysfs_remove_group(&dev->kobj, &thermal_attr_group);
 449
 450         return err;
 451 }
 452
 453 static void thermal_throttle_remove_dev(struct device *dev)
 454 {
 455         sysfs_remove_group(&dev->kobj, &thermal_attr_group);
 456 }
 457
 458 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
 459 static int thermal_throttle_online(unsigned int cpu)
 460 {
 461         struct thermal_state *state = &per_cpu(thermal_state, cpu);
 462         struct device *dev = get_cpu_device(cpu);
 463
 464         state->package_throttle.level = PACKAGE_LEVEL;
 465         state->core_throttle.level = CORE_LEVEL;
 466
 467         INIT_DELAYED_WORK(&state->package_throttle.therm_work, throttle_active_work);
 468         INIT_DELAYED_WORK(&state->core_throttle.therm_work, throttle_active_work);
 469
 470         return thermal_throttle_add_dev(dev, cpu);
 471 }
 472
 473 static int thermal_throttle_offline(unsigned int cpu)
 474 {
 475         struct thermal_state *state = &per_cpu(thermal_state, cpu);
 476         struct device *dev = get_cpu_device(cpu);
 477
 478         cancel_delayed_work(&state->package_throttle.therm_work);
 479         cancel_delayed_work(&state->core_throttle.therm_work);
 480
 481         state->package_throttle.rate_control_active = false;
 482         state->core_throttle.rate_control_active = false;
 483
 484         thermal_throttle_remove_dev(dev);
 485         return 0;
 486 }
 487
 488 static __init int thermal_throttle_init_device(void)
 489 {
 490         int ret;
 491
 492         if (!atomic_read(&therm_throt_en))
 493                 return 0;
 494
 495         ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/therm:online",
 496                                 thermal_throttle_online,
 497                                 thermal_throttle_offline);
 498         return ret < 0 ? ret : 0;
 499 }
 500 device_initcall(thermal_throttle_init_device);
 501
 502 #endif /* CONFIG_SYSFS */
 503
 504 static void notify_package_thresholds(__u64 msr_val)
 505 {
 506         bool notify_thres_0 = false;
 507         bool notify_thres_1 = false;
 508
 509         if (!platform_thermal_package_notify)
 510                 return;
 511
 512         /* lower threshold check */
 513         if (msr_val & THERM_LOG_THRESHOLD0)
 514                 notify_thres_0 = true;
 515         /* higher threshold check */
 516         if (msr_val & THERM_LOG_THRESHOLD1)
 517                 notify_thres_1 = true;
 518
 519         if (!notify_thres_0 && !notify_thres_1)
 520                 return;
 521
 522         if (platform_thermal_package_rate_control &&
 523                 platform_thermal_package_rate_control()) {
 524                 /* Rate control is implemented in callback */
 525                 platform_thermal_package_notify(msr_val);
 526                 return;
 527         }
 528
 529         /* lower threshold reached */
 530         if (notify_thres_0 && thresh_event_valid(PACKAGE_LEVEL, 0))
 531                 platform_thermal_package_notify(msr_val);
 532         /* higher threshold reached */
 533         if (notify_thres_1 && thresh_event_valid(PACKAGE_LEVEL, 1))
 534                 platform_thermal_package_notify(msr_val);
 535 }
 536
 537 static void notify_thresholds(__u64 msr_val)
 538 {
 539         /* check whether the interrupt handler is defined;
 540          * otherwise simply return
 541          */
 542         if (!platform_thermal_notify)
 543                 return;
 544
 545         /* lower threshold reached */
 546         if ((msr_val & THERM_LOG_THRESHOLD0) &&
 547                         thresh_event_valid(CORE_LEVEL, 0))
 548                 platform_thermal_notify(msr_val);
 549         /* higher threshold reached */
 550         if ((msr_val & THERM_LOG_THRESHOLD1) &&
 551                         thresh_event_valid(CORE_LEVEL, 1))
 552                 platform_thermal_notify(msr_val);
 553 }
 554
 555 /* Thermal transition interrupt handler */
 556 static void intel_thermal_interrupt(void)
 557 {
 558         __u64 msr_val;
 559
 560         if (static_cpu_has(X86_FEATURE_HWP))
 561                 wrmsrl_safe(MSR_HWP_STATUS, 0);
 562
 563         rdmsrl(MSR_IA32_THERM_STATUS, msr_val);
 564
 565         /* Check for violation of core thermal thresholds*/
 566         notify_thresholds(msr_val);
 567
 568         therm_throt_process(msr_val & THERM_STATUS_PROCHOT,
 569                             THERMAL_THROTTLING_EVENT,
 570                             CORE_LEVEL);
 571
 572         if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
 573                 therm_throt_process(msr_val & THERM_STATUS_POWER_LIMIT,
 574                                         POWER_LIMIT_EVENT,
 575                                         CORE_LEVEL);
 576
 577         if (this_cpu_has(X86_FEATURE_PTS)) {
 578                 rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val);
 579                 /* check violations of package thermal thresholds */
 580                 notify_package_thresholds(msr_val);
 581                 therm_throt_process(msr_val & PACKAGE_THERM_STATUS_PROCHOT,
 582                                         THERMAL_THROTTLING_EVENT,
 583                                         PACKAGE_LEVEL);
 584                 if (this_cpu_has(X86_FEATURE_PLN) && int_pln_enable)
 585                         therm_throt_process(msr_val &
 586                                         PACKAGE_THERM_STATUS_POWER_LIMIT,
 587                                         POWER_LIMIT_EVENT,
 588                                         PACKAGE_LEVEL);
 589         }
 590 }
 591
 592 static void unexpected_thermal_interrupt(void)
 593 {
 594         pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
 595                 smp_processor_id());
 596 }
 597
 598 static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
 599
 600 asmlinkage __visible void __irq_entry smp_thermal_interrupt(struct pt_regs *regs)
 601 {
 602         entering_irq();
 603         trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
 604         inc_irq_stat(irq_thermal_count);
 605         smp_thermal_vector();
 606         trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
 607         exiting_ack_irq();
 608 }
 609
 610 /* Thermal monitoring depends on APIC, ACPI and clock modulation */
 611 static int intel_thermal_supported(struct cpuinfo_x86 *c)
 612 {
 613         if (!boot_cpu_has(X86_FEATURE_APIC))
 614                 return 0;
 615         if (!cpu_has(c, X86_FEATURE_ACPI) || !cpu_has(c, X86_FEATURE_ACC))
 616                 return 0;
 617         return 1;
 618 }
 619
 620 void __init mcheck_intel_therm_init(void)
 621 {
 622         /*
 623          * This function is only called on boot CPU. Save the init thermal
 624          * LVT value on BSP and use that value to restore APs' thermal LVT
 625          * entry BIOS programmed later
 626          */
 627         if (intel_thermal_supported(&boot_cpu_data))
 628                 lvtthmr_init = apic_read(APIC_LVTTHMR);
 629 }
 630
 631 void intel_init_thermal(struct cpuinfo_x86 *c)
 632 {
 633         unsigned int cpu = smp_processor_id();
 634         int tm2 = 0;
 635         u32 l, h;
 636
 637         if (!intel_thermal_supported(c))
 638                 return;
 639
 640         /*
 641          * First check if its enabled already, in which case there might
 642          * be some SMM goo which handles it, so we can't even put a handler
 643          * since it might be delivered via SMI already:
 644          */
 645         rdmsr(MSR_IA32_MISC_ENABLE, l, h);
 646
 647         h = lvtthmr_init;
 648         /*
 649          * The initial value of thermal LVT entries on all APs always reads
 650          * 0x10000 because APs are woken up by BSP issuing INIT-SIPI-SIPI
 651          * sequence to them and LVT registers are reset to 0s except for
 652          * the mask bits which are set to 1s when APs receive INIT IPI.
 653          * If BIOS takes over the thermal interrupt and sets its interrupt
 654          * delivery mode to SMI (not fixed), it restores the value that the
 655          * BIOS has programmed on AP based on BSP's info we saved since BIOS
 656          * is always setting the same value for all threads/cores.
 657          */
 658         if ((h & APIC_DM_FIXED_MASK) != APIC_DM_FIXED)
 659                 apic_write(APIC_LVTTHMR, lvtthmr_init);
 660
 661
 662         if ((l & MSR_IA32_MISC_ENABLE_TM1) && (h & APIC_DM_SMI)) {
 663                 if (system_state == SYSTEM_BOOTING)
 664                         pr_debug("CPU%d: Thermal monitoring handled by SMI\n", cpu);
 665                 return;
 666         }
 667
 668         /* early Pentium M models use different method for enabling TM2 */
 669         if (cpu_has(c, X86_FEATURE_TM2)) {
 670                 if (c->x86 == 6 && (c->x86_model == 9 || c->x86_model == 13)) {
 671                         rdmsr(MSR_THERM2_CTL, l, h);
 672                         if (l & MSR_THERM2_CTL_TM_SELECT)
 673                                 tm2 = 1;
 674                 } else if (l & MSR_IA32_MISC_ENABLE_TM2)
 675                         tm2 = 1;
 676         }
 677
 678         /* We'll mask the thermal vector in the lapic till we're ready: */
 679         h = THERMAL_APIC_VECTOR | APIC_DM_FIXED | APIC_LVT_MASKED;
 680         apic_write(APIC_LVTTHMR, h);
 681
 682         rdmsr(MSR_IA32_THERM_INTERRUPT, l, h);
 683         if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable)
 684                 wrmsr(MSR_IA32_THERM_INTERRUPT,
 685                         (l | (THERM_INT_LOW_ENABLE
 686                         | THERM_INT_HIGH_ENABLE)) & ~THERM_INT_PLN_ENABLE, h);
 687         else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
 688                 wrmsr(MSR_IA32_THERM_INTERRUPT,
 689                         l | (THERM_INT_LOW_ENABLE
 690                         | THERM_INT_HIGH_ENABLE | THERM_INT_PLN_ENABLE), h);
 691         else
 692                 wrmsr(MSR_IA32_THERM_INTERRUPT,
 693                       l | (THERM_INT_LOW_ENABLE | THERM_INT_HIGH_ENABLE), h);
 694
 695         if (cpu_has(c, X86_FEATURE_PTS)) {
 696                 rdmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT, l, h);
 697                 if (cpu_has(c, X86_FEATURE_PLN) && !int_pln_enable)
 698                         wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
 699                                 (l | (PACKAGE_THERM_INT_LOW_ENABLE
 700                                 | PACKAGE_THERM_INT_HIGH_ENABLE))
 701                                 & ~PACKAGE_THERM_INT_PLN_ENABLE, h);
 702                 else if (cpu_has(c, X86_FEATURE_PLN) && int_pln_enable)
 703                         wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
 704                                 l | (PACKAGE_THERM_INT_LOW_ENABLE
 705                                 | PACKAGE_THERM_INT_HIGH_ENABLE
 706                                 | PACKAGE_THERM_INT_PLN_ENABLE), h);
 707                 else
 708                         wrmsr(MSR_IA32_PACKAGE_THERM_INTERRUPT,
 709                               l | (PACKAGE_THERM_INT_LOW_ENABLE
 710                                 | PACKAGE_THERM_INT_HIGH_ENABLE), h);
 711         }
 712
 713         smp_thermal_vector = intel_thermal_interrupt;
 714
 715         rdmsr(MSR_IA32_MISC_ENABLE, l, h);
 716         wrmsr(MSR_IA32_MISC_ENABLE, l | MSR_IA32_MISC_ENABLE_TM1, h);
 717
 718         /* Unmask the thermal vector: */
 719         l = apic_read(APIC_LVTTHMR);
 720         apic_write(APIC_LVTTHMR, l & ~APIC_LVT_MASKED);
 721
 722         pr_info_once("CPU0: Thermal monitoring enabled (%s)\n",
 723                       tm2 ? "TM2" : "TM1");
 724
 725         /* enable thermal throttle processing */
 726         atomic_set(&therm_throt_en, 1);
 727 }