drivers/idle/intel_idle.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * intel_idle.c - native hardware idle loop for modern Intel processors
   4  *
   5  * Copyright (c) 2013 - 2020, Intel Corporation.
   6  * Len Brown <len.brown@intel.com>
   7  * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   8  */
   9
  10 /*
  11  * intel_idle is a cpuidle driver that loads on all Intel CPUs with MWAIT
  12  * in lieu of the legacy ACPI processor_idle driver.  The intent is to
  13  * make Linux more efficient on these processors, as intel_idle knows
  14  * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs.
  15  */
  16
  17 /*
  18  * Design Assumptions
  19  *
  20  * All CPUs have same idle states as boot CPU
  21  *
  22  * Chipset BM_STS (bus master status) bit is a NOP
  23  *      for preventing entry into deep C-states
  24  *
  25  * CPU will flush caches as needed when entering a C-state via MWAIT
  26  *      (in contrast to entering ACPI C3, in which case the WBINVD
  27  *      instruction needs to be executed to flush the caches)
  28  */
  29
  30 /*
  31  * Known limitations
  32  *
  33  * ACPI has a .suspend hack to turn off deep c-statees during suspend
  34  * to avoid complications with the lapic timer workaround.
  35  * Have not seen issues with suspend, but may need same workaround here.
  36  *
  37  */
  38
  39 /* un-comment DEBUG to enable pr_debug() statements */
  40 #define DEBUG
  41
  42 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  43
  44 #include <linux/acpi.h>
  45 #include <linux/kernel.h>
  46 #include <linux/cpuidle.h>
  47 #include <linux/tick.h>
  48 #include <trace/events/power.h>
  49 #include <linux/sched.h>
  50 #include <linux/notifier.h>
  51 #include <linux/cpu.h>
  52 #include <linux/moduleparam.h>
  53 #include <asm/cpu_device_id.h>
  54 #include <asm/intel-family.h>
  55 #include <asm/mwait.h>
  56 #include <asm/msr.h>
  57
  58 #define INTEL_IDLE_VERSION "0.5.1"
  59
  60 static struct cpuidle_driver intel_idle_driver = {
  61         .name = "intel_idle",
  62         .owner = THIS_MODULE,
  63 };
  64 /* intel_idle.max_cstate=0 disables driver */
  65 static int max_cstate = CPUIDLE_STATE_MAX - 1;
  66 static unsigned int disabled_states_mask;
  67
  68 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
  69
  70 static unsigned long auto_demotion_disable_flags;
  71 static bool disable_promotion_to_c1e;
  72
  73 struct idle_cpu {
  74         struct cpuidle_state *state_table;
  75
  76         /*
  77          * Hardware C-state auto-demotion may not always be optimal.
  78          * Indicate which enable bits to clear here.
  79          */
  80         unsigned long auto_demotion_disable_flags;
  81         bool byt_auto_demotion_disable_flag;
  82         bool disable_promotion_to_c1e;
  83         bool use_acpi;
  84 };
  85
  86 static const struct idle_cpu *icpu __initdata;
  87 static struct cpuidle_state *cpuidle_state_table __initdata;
  88
  89 static unsigned int mwait_substates __initdata;
  90
  91 /*
  92  * Enable this state by default even if the ACPI _CST does not list it.
  93  */
  94 #define CPUIDLE_FLAG_ALWAYS_ENABLE      BIT(15)
  95
  96 /*
  97  * MWAIT takes an 8-bit "hint" in EAX "suggesting"
  98  * the C-state (top nibble) and sub-state (bottom nibble)
  99  * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
 100  *
 101  * We store the hint at the top of our "flags" for each state.
 102  */
 103 #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
 104 #define MWAIT2flg(eax) ((eax & 0xFF) << 24)
 105
 106 /**
 107  * intel_idle - Ask the processor to enter the given idle state.
 108  * @dev: cpuidle device of the target CPU.
 109  * @drv: cpuidle driver (assumed to point to intel_idle_driver).
 110  * @index: Target idle state index.
 111  *
 112  * Use the MWAIT instruction to notify the processor that the CPU represented by
 113  * @dev is idle and it can try to enter the idle state corresponding to @index.
 114  *
 115  * If the local APIC timer is not known to be reliable in the target idle state,
 116  * enable one-shot tick broadcasting for the target CPU before executing MWAIT.
 117  *
 118  * Optionally call leave_mm() for the target CPU upfront to avoid wakeups due to
 119  * flushing user TLBs.
 120  *
 121  * Must be called under local_irq_disable().
 122  */
 123 static __cpuidle int intel_idle(struct cpuidle_device *dev,
 124                                 struct cpuidle_driver *drv, int index)
 125 {
 126         struct cpuidle_state *state = &drv->states[index];
 127         unsigned long eax = flg2MWAIT(state->flags);
 128         unsigned long ecx = 1; /* break on interrupt flag */
 129
 130         mwait_idle_with_hints(eax, ecx);
 131
 132         return index;
 133 }
 134
 135 /**
 136  * intel_idle_s2idle - Ask the processor to enter the given idle state.
 137  * @dev: cpuidle device of the target CPU.
 138  * @drv: cpuidle driver (assumed to point to intel_idle_driver).
 139  * @index: Target idle state index.
 140  *
 141  * Use the MWAIT instruction to notify the processor that the CPU represented by
 142  * @dev is idle and it can try to enter the idle state corresponding to @index.
 143  *
 144  * Invoked as a suspend-to-idle callback routine with frozen user space, frozen
 145  * scheduler tick and suspended scheduler clock on the target CPU.
 146  */
 147 static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev,
 148                                        struct cpuidle_driver *drv, int index)
 149 {
 150         unsigned long eax = flg2MWAIT(drv->states[index].flags);
 151         unsigned long ecx = 1; /* break on interrupt flag */
 152
 153         mwait_idle_with_hints(eax, ecx);
 154
 155         return 0;
 156 }
 157
 158 /*
 159  * States are indexed by the cstate number,
 160  * which is also the index into the MWAIT hint array.
 161  * Thus C0 is a dummy.
 162  */
 163 static struct cpuidle_state nehalem_cstates[] __initdata = {
 164         {
 165                 .name = "C1",
 166                 .desc = "MWAIT 0x00",
 167                 .flags = MWAIT2flg(0x00),
 168                 .exit_latency = 3,
 169                 .target_residency = 6,
 170                 .enter = &intel_idle,
 171                 .enter_s2idle = intel_idle_s2idle, },
 172         {
 173                 .name = "C1E",
 174                 .desc = "MWAIT 0x01",
 175                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 176                 .exit_latency = 10,
 177                 .target_residency = 20,
 178                 .enter = &intel_idle,
 179                 .enter_s2idle = intel_idle_s2idle, },
 180         {
 181                 .name = "C3",
 182                 .desc = "MWAIT 0x10",
 183                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 184                 .exit_latency = 20,
 185                 .target_residency = 80,
 186                 .enter = &intel_idle,
 187                 .enter_s2idle = intel_idle_s2idle, },
 188         {
 189                 .name = "C6",
 190                 .desc = "MWAIT 0x20",
 191                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 192                 .exit_latency = 200,
 193                 .target_residency = 800,
 194                 .enter = &intel_idle,
 195                 .enter_s2idle = intel_idle_s2idle, },
 196         {
 197                 .enter = NULL }
 198 };
 199
 200 static struct cpuidle_state snb_cstates[] __initdata = {
 201         {
 202                 .name = "C1",
 203                 .desc = "MWAIT 0x00",
 204                 .flags = MWAIT2flg(0x00),
 205                 .exit_latency = 2,
 206                 .target_residency = 2,
 207                 .enter = &intel_idle,
 208                 .enter_s2idle = intel_idle_s2idle, },
 209         {
 210                 .name = "C1E",
 211                 .desc = "MWAIT 0x01",
 212                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 213                 .exit_latency = 10,
 214                 .target_residency = 20,
 215                 .enter = &intel_idle,
 216                 .enter_s2idle = intel_idle_s2idle, },
 217         {
 218                 .name = "C3",
 219                 .desc = "MWAIT 0x10",
 220                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 221                 .exit_latency = 80,
 222                 .target_residency = 211,
 223                 .enter = &intel_idle,
 224                 .enter_s2idle = intel_idle_s2idle, },
 225         {
 226                 .name = "C6",
 227                 .desc = "MWAIT 0x20",
 228                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 229                 .exit_latency = 104,
 230                 .target_residency = 345,
 231                 .enter = &intel_idle,
 232                 .enter_s2idle = intel_idle_s2idle, },
 233         {
 234                 .name = "C7",
 235                 .desc = "MWAIT 0x30",
 236                 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 237                 .exit_latency = 109,
 238                 .target_residency = 345,
 239                 .enter = &intel_idle,
 240                 .enter_s2idle = intel_idle_s2idle, },
 241         {
 242                 .enter = NULL }
 243 };
 244
 245 static struct cpuidle_state byt_cstates[] __initdata = {
 246         {
 247                 .name = "C1",
 248                 .desc = "MWAIT 0x00",
 249                 .flags = MWAIT2flg(0x00),
 250                 .exit_latency = 1,
 251                 .target_residency = 1,
 252                 .enter = &intel_idle,
 253                 .enter_s2idle = intel_idle_s2idle, },
 254         {
 255                 .name = "C6N",
 256                 .desc = "MWAIT 0x58",
 257                 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
 258                 .exit_latency = 300,
 259                 .target_residency = 275,
 260                 .enter = &intel_idle,
 261                 .enter_s2idle = intel_idle_s2idle, },
 262         {
 263                 .name = "C6S",
 264                 .desc = "MWAIT 0x52",
 265                 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 266                 .exit_latency = 500,
 267                 .target_residency = 560,
 268                 .enter = &intel_idle,
 269                 .enter_s2idle = intel_idle_s2idle, },
 270         {
 271                 .name = "C7",
 272                 .desc = "MWAIT 0x60",
 273                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 274                 .exit_latency = 1200,
 275                 .target_residency = 4000,
 276                 .enter = &intel_idle,
 277                 .enter_s2idle = intel_idle_s2idle, },
 278         {
 279                 .name = "C7S",
 280                 .desc = "MWAIT 0x64",
 281                 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
 282                 .exit_latency = 10000,
 283                 .target_residency = 20000,
 284                 .enter = &intel_idle,
 285                 .enter_s2idle = intel_idle_s2idle, },
 286         {
 287                 .enter = NULL }
 288 };
 289
 290 static struct cpuidle_state cht_cstates[] __initdata = {
 291         {
 292                 .name = "C1",
 293                 .desc = "MWAIT 0x00",
 294                 .flags = MWAIT2flg(0x00),
 295                 .exit_latency = 1,
 296                 .target_residency = 1,
 297                 .enter = &intel_idle,
 298                 .enter_s2idle = intel_idle_s2idle, },
 299         {
 300                 .name = "C6N",
 301                 .desc = "MWAIT 0x58",
 302                 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
 303                 .exit_latency = 80,
 304                 .target_residency = 275,
 305                 .enter = &intel_idle,
 306                 .enter_s2idle = intel_idle_s2idle, },
 307         {
 308                 .name = "C6S",
 309                 .desc = "MWAIT 0x52",
 310                 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 311                 .exit_latency = 200,
 312                 .target_residency = 560,
 313                 .enter = &intel_idle,
 314                 .enter_s2idle = intel_idle_s2idle, },
 315         {
 316                 .name = "C7",
 317                 .desc = "MWAIT 0x60",
 318                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 319                 .exit_latency = 1200,
 320                 .target_residency = 4000,
 321                 .enter = &intel_idle,
 322                 .enter_s2idle = intel_idle_s2idle, },
 323         {
 324                 .name = "C7S",
 325                 .desc = "MWAIT 0x64",
 326                 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
 327                 .exit_latency = 10000,
 328                 .target_residency = 20000,
 329                 .enter = &intel_idle,
 330                 .enter_s2idle = intel_idle_s2idle, },
 331         {
 332                 .enter = NULL }
 333 };
 334
 335 static struct cpuidle_state ivb_cstates[] __initdata = {
 336         {
 337                 .name = "C1",
 338                 .desc = "MWAIT 0x00",
 339                 .flags = MWAIT2flg(0x00),
 340                 .exit_latency = 1,
 341                 .target_residency = 1,
 342                 .enter = &intel_idle,
 343                 .enter_s2idle = intel_idle_s2idle, },
 344         {
 345                 .name = "C1E",
 346                 .desc = "MWAIT 0x01",
 347                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 348                 .exit_latency = 10,
 349                 .target_residency = 20,
 350                 .enter = &intel_idle,
 351                 .enter_s2idle = intel_idle_s2idle, },
 352         {
 353                 .name = "C3",
 354                 .desc = "MWAIT 0x10",
 355                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 356                 .exit_latency = 59,
 357                 .target_residency = 156,
 358                 .enter = &intel_idle,
 359                 .enter_s2idle = intel_idle_s2idle, },
 360         {
 361                 .name = "C6",
 362                 .desc = "MWAIT 0x20",
 363                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 364                 .exit_latency = 80,
 365                 .target_residency = 300,
 366                 .enter = &intel_idle,
 367                 .enter_s2idle = intel_idle_s2idle, },
 368         {
 369                 .name = "C7",
 370                 .desc = "MWAIT 0x30",
 371                 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 372                 .exit_latency = 87,
 373                 .target_residency = 300,
 374                 .enter = &intel_idle,
 375                 .enter_s2idle = intel_idle_s2idle, },
 376         {
 377                 .enter = NULL }
 378 };
 379
 380 static struct cpuidle_state ivt_cstates[] __initdata = {
 381         {
 382                 .name = "C1",
 383                 .desc = "MWAIT 0x00",
 384                 .flags = MWAIT2flg(0x00),
 385                 .exit_latency = 1,
 386                 .target_residency = 1,
 387                 .enter = &intel_idle,
 388                 .enter_s2idle = intel_idle_s2idle, },
 389         {
 390                 .name = "C1E",
 391                 .desc = "MWAIT 0x01",
 392                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 393                 .exit_latency = 10,
 394                 .target_residency = 80,
 395                 .enter = &intel_idle,
 396                 .enter_s2idle = intel_idle_s2idle, },
 397         {
 398                 .name = "C3",
 399                 .desc = "MWAIT 0x10",
 400                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 401                 .exit_latency = 59,
 402                 .target_residency = 156,
 403                 .enter = &intel_idle,
 404                 .enter_s2idle = intel_idle_s2idle, },
 405         {
 406                 .name = "C6",
 407                 .desc = "MWAIT 0x20",
 408                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 409                 .exit_latency = 82,
 410                 .target_residency = 300,
 411                 .enter = &intel_idle,
 412                 .enter_s2idle = intel_idle_s2idle, },
 413         {
 414                 .enter = NULL }
 415 };
 416
 417 static struct cpuidle_state ivt_cstates_4s[] __initdata = {
 418         {
 419                 .name = "C1",
 420                 .desc = "MWAIT 0x00",
 421                 .flags = MWAIT2flg(0x00),
 422                 .exit_latency = 1,
 423                 .target_residency = 1,
 424                 .enter = &intel_idle,
 425                 .enter_s2idle = intel_idle_s2idle, },
 426         {
 427                 .name = "C1E",
 428                 .desc = "MWAIT 0x01",
 429                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 430                 .exit_latency = 10,
 431                 .target_residency = 250,
 432                 .enter = &intel_idle,
 433                 .enter_s2idle = intel_idle_s2idle, },
 434         {
 435                 .name = "C3",
 436                 .desc = "MWAIT 0x10",
 437                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 438                 .exit_latency = 59,
 439                 .target_residency = 300,
 440                 .enter = &intel_idle,
 441                 .enter_s2idle = intel_idle_s2idle, },
 442         {
 443                 .name = "C6",
 444                 .desc = "MWAIT 0x20",
 445                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 446                 .exit_latency = 84,
 447                 .target_residency = 400,
 448                 .enter = &intel_idle,
 449                 .enter_s2idle = intel_idle_s2idle, },
 450         {
 451                 .enter = NULL }
 452 };
 453
 454 static struct cpuidle_state ivt_cstates_8s[] __initdata = {
 455         {
 456                 .name = "C1",
 457                 .desc = "MWAIT 0x00",
 458                 .flags = MWAIT2flg(0x00),
 459                 .exit_latency = 1,
 460                 .target_residency = 1,
 461                 .enter = &intel_idle,
 462                 .enter_s2idle = intel_idle_s2idle, },
 463         {
 464                 .name = "C1E",
 465                 .desc = "MWAIT 0x01",
 466                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 467                 .exit_latency = 10,
 468                 .target_residency = 500,
 469                 .enter = &intel_idle,
 470                 .enter_s2idle = intel_idle_s2idle, },
 471         {
 472                 .name = "C3",
 473                 .desc = "MWAIT 0x10",
 474                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 475                 .exit_latency = 59,
 476                 .target_residency = 600,
 477                 .enter = &intel_idle,
 478                 .enter_s2idle = intel_idle_s2idle, },
 479         {
 480                 .name = "C6",
 481                 .desc = "MWAIT 0x20",
 482                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 483                 .exit_latency = 88,
 484                 .target_residency = 700,
 485                 .enter = &intel_idle,
 486                 .enter_s2idle = intel_idle_s2idle, },
 487         {
 488                 .enter = NULL }
 489 };
 490
 491 static struct cpuidle_state hsw_cstates[] __initdata = {
 492         {
 493                 .name = "C1",
 494                 .desc = "MWAIT 0x00",
 495                 .flags = MWAIT2flg(0x00),
 496                 .exit_latency = 2,
 497                 .target_residency = 2,
 498                 .enter = &intel_idle,
 499                 .enter_s2idle = intel_idle_s2idle, },
 500         {
 501                 .name = "C1E",
 502                 .desc = "MWAIT 0x01",
 503                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 504                 .exit_latency = 10,
 505                 .target_residency = 20,
 506                 .enter = &intel_idle,
 507                 .enter_s2idle = intel_idle_s2idle, },
 508         {
 509                 .name = "C3",
 510                 .desc = "MWAIT 0x10",
 511                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 512                 .exit_latency = 33,
 513                 .target_residency = 100,
 514                 .enter = &intel_idle,
 515                 .enter_s2idle = intel_idle_s2idle, },
 516         {
 517                 .name = "C6",
 518                 .desc = "MWAIT 0x20",
 519                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 520                 .exit_latency = 133,
 521                 .target_residency = 400,
 522                 .enter = &intel_idle,
 523                 .enter_s2idle = intel_idle_s2idle, },
 524         {
 525                 .name = "C7s",
 526                 .desc = "MWAIT 0x32",
 527                 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
 528                 .exit_latency = 166,
 529                 .target_residency = 500,
 530                 .enter = &intel_idle,
 531                 .enter_s2idle = intel_idle_s2idle, },
 532         {
 533                 .name = "C8",
 534                 .desc = "MWAIT 0x40",
 535                 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 536                 .exit_latency = 300,
 537                 .target_residency = 900,
 538                 .enter = &intel_idle,
 539                 .enter_s2idle = intel_idle_s2idle, },
 540         {
 541                 .name = "C9",
 542                 .desc = "MWAIT 0x50",
 543                 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 544                 .exit_latency = 600,
 545                 .target_residency = 1800,
 546                 .enter = &intel_idle,
 547                 .enter_s2idle = intel_idle_s2idle, },
 548         {
 549                 .name = "C10",
 550                 .desc = "MWAIT 0x60",
 551                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 552                 .exit_latency = 2600,
 553                 .target_residency = 7700,
 554                 .enter = &intel_idle,
 555                 .enter_s2idle = intel_idle_s2idle, },
 556         {
 557                 .enter = NULL }
 558 };
 559 static struct cpuidle_state bdw_cstates[] __initdata = {
 560         {
 561                 .name = "C1",
 562                 .desc = "MWAIT 0x00",
 563                 .flags = MWAIT2flg(0x00),
 564                 .exit_latency = 2,
 565                 .target_residency = 2,
 566                 .enter = &intel_idle,
 567                 .enter_s2idle = intel_idle_s2idle, },
 568         {
 569                 .name = "C1E",
 570                 .desc = "MWAIT 0x01",
 571                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 572                 .exit_latency = 10,
 573                 .target_residency = 20,
 574                 .enter = &intel_idle,
 575                 .enter_s2idle = intel_idle_s2idle, },
 576         {
 577                 .name = "C3",
 578                 .desc = "MWAIT 0x10",
 579                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 580                 .exit_latency = 40,
 581                 .target_residency = 100,
 582                 .enter = &intel_idle,
 583                 .enter_s2idle = intel_idle_s2idle, },
 584         {
 585                 .name = "C6",
 586                 .desc = "MWAIT 0x20",
 587                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 588                 .exit_latency = 133,
 589                 .target_residency = 400,
 590                 .enter = &intel_idle,
 591                 .enter_s2idle = intel_idle_s2idle, },
 592         {
 593                 .name = "C7s",
 594                 .desc = "MWAIT 0x32",
 595                 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
 596                 .exit_latency = 166,
 597                 .target_residency = 500,
 598                 .enter = &intel_idle,
 599                 .enter_s2idle = intel_idle_s2idle, },
 600         {
 601                 .name = "C8",
 602                 .desc = "MWAIT 0x40",
 603                 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 604                 .exit_latency = 300,
 605                 .target_residency = 900,
 606                 .enter = &intel_idle,
 607                 .enter_s2idle = intel_idle_s2idle, },
 608         {
 609                 .name = "C9",
 610                 .desc = "MWAIT 0x50",
 611                 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 612                 .exit_latency = 600,
 613                 .target_residency = 1800,
 614                 .enter = &intel_idle,
 615                 .enter_s2idle = intel_idle_s2idle, },
 616         {
 617                 .name = "C10",
 618                 .desc = "MWAIT 0x60",
 619                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 620                 .exit_latency = 2600,
 621                 .target_residency = 7700,
 622                 .enter = &intel_idle,
 623                 .enter_s2idle = intel_idle_s2idle, },
 624         {
 625                 .enter = NULL }
 626 };
 627
 628 static struct cpuidle_state skl_cstates[] __initdata = {
 629         {
 630                 .name = "C1",
 631                 .desc = "MWAIT 0x00",
 632                 .flags = MWAIT2flg(0x00),
 633                 .exit_latency = 2,
 634                 .target_residency = 2,
 635                 .enter = &intel_idle,
 636                 .enter_s2idle = intel_idle_s2idle, },
 637         {
 638                 .name = "C1E",
 639                 .desc = "MWAIT 0x01",
 640                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 641                 .exit_latency = 10,
 642                 .target_residency = 20,
 643                 .enter = &intel_idle,
 644                 .enter_s2idle = intel_idle_s2idle, },
 645         {
 646                 .name = "C3",
 647                 .desc = "MWAIT 0x10",
 648                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 649                 .exit_latency = 70,
 650                 .target_residency = 100,
 651                 .enter = &intel_idle,
 652                 .enter_s2idle = intel_idle_s2idle, },
 653         {
 654                 .name = "C6",
 655                 .desc = "MWAIT 0x20",
 656                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 657                 .exit_latency = 85,
 658                 .target_residency = 200,
 659                 .enter = &intel_idle,
 660                 .enter_s2idle = intel_idle_s2idle, },
 661         {
 662                 .name = "C7s",
 663                 .desc = "MWAIT 0x33",
 664                 .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED,
 665                 .exit_latency = 124,
 666                 .target_residency = 800,
 667                 .enter = &intel_idle,
 668                 .enter_s2idle = intel_idle_s2idle, },
 669         {
 670                 .name = "C8",
 671                 .desc = "MWAIT 0x40",
 672                 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 673                 .exit_latency = 200,
 674                 .target_residency = 800,
 675                 .enter = &intel_idle,
 676                 .enter_s2idle = intel_idle_s2idle, },
 677         {
 678                 .name = "C9",
 679                 .desc = "MWAIT 0x50",
 680                 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 681                 .exit_latency = 480,
 682                 .target_residency = 5000,
 683                 .enter = &intel_idle,
 684                 .enter_s2idle = intel_idle_s2idle, },
 685         {
 686                 .name = "C10",
 687                 .desc = "MWAIT 0x60",
 688                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 689                 .exit_latency = 890,
 690                 .target_residency = 5000,
 691                 .enter = &intel_idle,
 692                 .enter_s2idle = intel_idle_s2idle, },
 693         {
 694                 .enter = NULL }
 695 };
 696
 697 static struct cpuidle_state skx_cstates[] __initdata = {
 698         {
 699                 .name = "C1",
 700                 .desc = "MWAIT 0x00",
 701                 .flags = MWAIT2flg(0x00),
 702                 .exit_latency = 2,
 703                 .target_residency = 2,
 704                 .enter = &intel_idle,
 705                 .enter_s2idle = intel_idle_s2idle, },
 706         {
 707                 .name = "C1E",
 708                 .desc = "MWAIT 0x01",
 709                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 710                 .exit_latency = 10,
 711                 .target_residency = 20,
 712                 .enter = &intel_idle,
 713                 .enter_s2idle = intel_idle_s2idle, },
 714         {
 715                 .name = "C6",
 716                 .desc = "MWAIT 0x20",
 717                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 718                 .exit_latency = 133,
 719                 .target_residency = 600,
 720                 .enter = &intel_idle,
 721                 .enter_s2idle = intel_idle_s2idle, },
 722         {
 723                 .enter = NULL }
 724 };
 725
 726 static struct cpuidle_state icx_cstates[] __initdata = {
 727         {
 728                 .name = "C1",
 729                 .desc = "MWAIT 0x00",
 730                 .flags = MWAIT2flg(0x00),
 731                 .exit_latency = 1,
 732                 .target_residency = 1,
 733                 .enter = &intel_idle,
 734                 .enter_s2idle = intel_idle_s2idle, },
 735         {
 736                 .name = "C1E",
 737                 .desc = "MWAIT 0x01",
 738                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 739                 .exit_latency = 4,
 740                 .target_residency = 4,
 741                 .enter = &intel_idle,
 742                 .enter_s2idle = intel_idle_s2idle, },
 743         {
 744                 .name = "C6",
 745                 .desc = "MWAIT 0x20",
 746                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 747                 .exit_latency = 128,
 748                 .target_residency = 384,
 749                 .enter = &intel_idle,
 750                 .enter_s2idle = intel_idle_s2idle, },
 751         {
 752                 .enter = NULL }
 753 };
 754
 755 static struct cpuidle_state atom_cstates[] __initdata = {
 756         {
 757                 .name = "C1E",
 758                 .desc = "MWAIT 0x00",
 759                 .flags = MWAIT2flg(0x00),
 760                 .exit_latency = 10,
 761                 .target_residency = 20,
 762                 .enter = &intel_idle,
 763                 .enter_s2idle = intel_idle_s2idle, },
 764         {
 765                 .name = "C2",
 766                 .desc = "MWAIT 0x10",
 767                 .flags = MWAIT2flg(0x10),
 768                 .exit_latency = 20,
 769                 .target_residency = 80,
 770                 .enter = &intel_idle,
 771                 .enter_s2idle = intel_idle_s2idle, },
 772         {
 773                 .name = "C4",
 774                 .desc = "MWAIT 0x30",
 775                 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 776                 .exit_latency = 100,
 777                 .target_residency = 400,
 778                 .enter = &intel_idle,
 779                 .enter_s2idle = intel_idle_s2idle, },
 780         {
 781                 .name = "C6",
 782                 .desc = "MWAIT 0x52",
 783                 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 784                 .exit_latency = 140,
 785                 .target_residency = 560,
 786                 .enter = &intel_idle,
 787                 .enter_s2idle = intel_idle_s2idle, },
 788         {
 789                 .enter = NULL }
 790 };
 791 static struct cpuidle_state tangier_cstates[] __initdata = {
 792         {
 793                 .name = "C1",
 794                 .desc = "MWAIT 0x00",
 795                 .flags = MWAIT2flg(0x00),
 796                 .exit_latency = 1,
 797                 .target_residency = 4,
 798                 .enter = &intel_idle,
 799                 .enter_s2idle = intel_idle_s2idle, },
 800         {
 801                 .name = "C4",
 802                 .desc = "MWAIT 0x30",
 803                 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
 804                 .exit_latency = 100,
 805                 .target_residency = 400,
 806                 .enter = &intel_idle,
 807                 .enter_s2idle = intel_idle_s2idle, },
 808         {
 809                 .name = "C6",
 810                 .desc = "MWAIT 0x52",
 811                 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
 812                 .exit_latency = 140,
 813                 .target_residency = 560,
 814                 .enter = &intel_idle,
 815                 .enter_s2idle = intel_idle_s2idle, },
 816         {
 817                 .name = "C7",
 818                 .desc = "MWAIT 0x60",
 819                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 820                 .exit_latency = 1200,
 821                 .target_residency = 4000,
 822                 .enter = &intel_idle,
 823                 .enter_s2idle = intel_idle_s2idle, },
 824         {
 825                 .name = "C9",
 826                 .desc = "MWAIT 0x64",
 827                 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
 828                 .exit_latency = 10000,
 829                 .target_residency = 20000,
 830                 .enter = &intel_idle,
 831                 .enter_s2idle = intel_idle_s2idle, },
 832         {
 833                 .enter = NULL }
 834 };
 835 static struct cpuidle_state avn_cstates[] __initdata = {
 836         {
 837                 .name = "C1",
 838                 .desc = "MWAIT 0x00",
 839                 .flags = MWAIT2flg(0x00),
 840                 .exit_latency = 2,
 841                 .target_residency = 2,
 842                 .enter = &intel_idle,
 843                 .enter_s2idle = intel_idle_s2idle, },
 844         {
 845                 .name = "C6",
 846                 .desc = "MWAIT 0x51",
 847                 .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED,
 848                 .exit_latency = 15,
 849                 .target_residency = 45,
 850                 .enter = &intel_idle,
 851                 .enter_s2idle = intel_idle_s2idle, },
 852         {
 853                 .enter = NULL }
 854 };
 855 static struct cpuidle_state knl_cstates[] __initdata = {
 856         {
 857                 .name = "C1",
 858                 .desc = "MWAIT 0x00",
 859                 .flags = MWAIT2flg(0x00),
 860                 .exit_latency = 1,
 861                 .target_residency = 2,
 862                 .enter = &intel_idle,
 863                 .enter_s2idle = intel_idle_s2idle },
 864         {
 865                 .name = "C6",
 866                 .desc = "MWAIT 0x10",
 867                 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
 868                 .exit_latency = 120,
 869                 .target_residency = 500,
 870                 .enter = &intel_idle,
 871                 .enter_s2idle = intel_idle_s2idle },
 872         {
 873                 .enter = NULL }
 874 };
 875
 876 static struct cpuidle_state bxt_cstates[] __initdata = {
 877         {
 878                 .name = "C1",
 879                 .desc = "MWAIT 0x00",
 880                 .flags = MWAIT2flg(0x00),
 881                 .exit_latency = 2,
 882                 .target_residency = 2,
 883                 .enter = &intel_idle,
 884                 .enter_s2idle = intel_idle_s2idle, },
 885         {
 886                 .name = "C1E",
 887                 .desc = "MWAIT 0x01",
 888                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 889                 .exit_latency = 10,
 890                 .target_residency = 20,
 891                 .enter = &intel_idle,
 892                 .enter_s2idle = intel_idle_s2idle, },
 893         {
 894                 .name = "C6",
 895                 .desc = "MWAIT 0x20",
 896                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 897                 .exit_latency = 133,
 898                 .target_residency = 133,
 899                 .enter = &intel_idle,
 900                 .enter_s2idle = intel_idle_s2idle, },
 901         {
 902                 .name = "C7s",
 903                 .desc = "MWAIT 0x31",
 904                 .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
 905                 .exit_latency = 155,
 906                 .target_residency = 155,
 907                 .enter = &intel_idle,
 908                 .enter_s2idle = intel_idle_s2idle, },
 909         {
 910                 .name = "C8",
 911                 .desc = "MWAIT 0x40",
 912                 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
 913                 .exit_latency = 1000,
 914                 .target_residency = 1000,
 915                 .enter = &intel_idle,
 916                 .enter_s2idle = intel_idle_s2idle, },
 917         {
 918                 .name = "C9",
 919                 .desc = "MWAIT 0x50",
 920                 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
 921                 .exit_latency = 2000,
 922                 .target_residency = 2000,
 923                 .enter = &intel_idle,
 924                 .enter_s2idle = intel_idle_s2idle, },
 925         {
 926                 .name = "C10",
 927                 .desc = "MWAIT 0x60",
 928                 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
 929                 .exit_latency = 10000,
 930                 .target_residency = 10000,
 931                 .enter = &intel_idle,
 932                 .enter_s2idle = intel_idle_s2idle, },
 933         {
 934                 .enter = NULL }
 935 };
 936
 937 static struct cpuidle_state dnv_cstates[] __initdata = {
 938         {
 939                 .name = "C1",
 940                 .desc = "MWAIT 0x00",
 941                 .flags = MWAIT2flg(0x00),
 942                 .exit_latency = 2,
 943                 .target_residency = 2,
 944                 .enter = &intel_idle,
 945                 .enter_s2idle = intel_idle_s2idle, },
 946         {
 947                 .name = "C1E",
 948                 .desc = "MWAIT 0x01",
 949                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 950                 .exit_latency = 10,
 951                 .target_residency = 20,
 952                 .enter = &intel_idle,
 953                 .enter_s2idle = intel_idle_s2idle, },
 954         {
 955                 .name = "C6",
 956                 .desc = "MWAIT 0x20",
 957                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 958                 .exit_latency = 50,
 959                 .target_residency = 500,
 960                 .enter = &intel_idle,
 961                 .enter_s2idle = intel_idle_s2idle, },
 962         {
 963                 .enter = NULL }
 964 };
 965
 966 /*
 967  * Note, depending on HW and FW revision, SnowRidge SoC may or may not support
 968  * C6, and this is indicated in the CPUID mwait leaf.
 969  */
 970 static struct cpuidle_state snr_cstates[] __initdata = {
 971         {
 972                 .name = "C1",
 973                 .desc = "MWAIT 0x00",
 974                 .flags = MWAIT2flg(0x00),
 975                 .exit_latency = 2,
 976                 .target_residency = 2,
 977                 .enter = &intel_idle,
 978                 .enter_s2idle = intel_idle_s2idle, },
 979         {
 980                 .name = "C1E",
 981                 .desc = "MWAIT 0x01",
 982                 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
 983                 .exit_latency = 15,
 984                 .target_residency = 25,
 985                 .enter = &intel_idle,
 986                 .enter_s2idle = intel_idle_s2idle, },
 987         {
 988                 .name = "C6",
 989                 .desc = "MWAIT 0x20",
 990                 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
 991                 .exit_latency = 130,
 992                 .target_residency = 500,
 993                 .enter = &intel_idle,
 994                 .enter_s2idle = intel_idle_s2idle, },
 995         {
 996                 .enter = NULL }
 997 };
 998
 999 static const struct idle_cpu idle_cpu_nehalem __initconst = {
1000         .state_table = nehalem_cstates,
1001         .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1002         .disable_promotion_to_c1e = true,
1003 };
1004
1005 static const struct idle_cpu idle_cpu_nhx __initconst = {
1006         .state_table = nehalem_cstates,
1007         .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1008         .disable_promotion_to_c1e = true,
1009         .use_acpi = true,
1010 };
1011
1012 static const struct idle_cpu idle_cpu_atom __initconst = {
1013         .state_table = atom_cstates,
1014 };
1015
1016 static const struct idle_cpu idle_cpu_tangier __initconst = {
1017         .state_table = tangier_cstates,
1018 };
1019
1020 static const struct idle_cpu idle_cpu_lincroft __initconst = {
1021         .state_table = atom_cstates,
1022         .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
1023 };
1024
1025 static const struct idle_cpu idle_cpu_snb __initconst = {
1026         .state_table = snb_cstates,
1027         .disable_promotion_to_c1e = true,
1028 };
1029
1030 static const struct idle_cpu idle_cpu_snx __initconst = {
1031         .state_table = snb_cstates,
1032         .disable_promotion_to_c1e = true,
1033         .use_acpi = true,
1034 };
1035
1036 static const struct idle_cpu idle_cpu_byt __initconst = {
1037         .state_table = byt_cstates,
1038         .disable_promotion_to_c1e = true,
1039         .byt_auto_demotion_disable_flag = true,
1040 };
1041
1042 static const struct idle_cpu idle_cpu_cht __initconst = {
1043         .state_table = cht_cstates,
1044         .disable_promotion_to_c1e = true,
1045         .byt_auto_demotion_disable_flag = true,
1046 };
1047
1048 static const struct idle_cpu idle_cpu_ivb __initconst = {
1049         .state_table = ivb_cstates,
1050         .disable_promotion_to_c1e = true,
1051 };
1052
1053 static const struct idle_cpu idle_cpu_ivt __initconst = {
1054         .state_table = ivt_cstates,
1055         .disable_promotion_to_c1e = true,
1056         .use_acpi = true,
1057 };
1058
1059 static const struct idle_cpu idle_cpu_hsw __initconst = {
1060         .state_table = hsw_cstates,
1061         .disable_promotion_to_c1e = true,
1062 };
1063
1064 static const struct idle_cpu idle_cpu_hsx __initconst = {
1065         .state_table = hsw_cstates,
1066         .disable_promotion_to_c1e = true,
1067         .use_acpi = true,
1068 };
1069
1070 static const struct idle_cpu idle_cpu_bdw __initconst = {
1071         .state_table = bdw_cstates,
1072         .disable_promotion_to_c1e = true,
1073 };
1074
1075 static const struct idle_cpu idle_cpu_bdx __initconst = {
1076         .state_table = bdw_cstates,
1077         .disable_promotion_to_c1e = true,
1078         .use_acpi = true,
1079 };
1080
1081 static const struct idle_cpu idle_cpu_skl __initconst = {
1082         .state_table = skl_cstates,
1083         .disable_promotion_to_c1e = true,
1084 };
1085
1086 static const struct idle_cpu idle_cpu_skx __initconst = {
1087         .state_table = skx_cstates,
1088         .disable_promotion_to_c1e = true,
1089         .use_acpi = true,
1090 };
1091
1092 static const struct idle_cpu idle_cpu_icx __initconst = {
1093         .state_table = icx_cstates,
1094         .disable_promotion_to_c1e = true,
1095         .use_acpi = true,
1096 };
1097
1098 static const struct idle_cpu idle_cpu_avn __initconst = {
1099         .state_table = avn_cstates,
1100         .disable_promotion_to_c1e = true,
1101         .use_acpi = true,
1102 };
1103
1104 static const struct idle_cpu idle_cpu_knl __initconst = {
1105         .state_table = knl_cstates,
1106         .use_acpi = true,
1107 };
1108
1109 static const struct idle_cpu idle_cpu_bxt __initconst = {
1110         .state_table = bxt_cstates,
1111         .disable_promotion_to_c1e = true,
1112 };
1113
1114 static const struct idle_cpu idle_cpu_dnv __initconst = {
1115         .state_table = dnv_cstates,
1116         .disable_promotion_to_c1e = true,
1117         .use_acpi = true,
1118 };
1119
1120 static const struct idle_cpu idle_cpu_snr __initconst = {
1121         .state_table = snr_cstates,
1122         .disable_promotion_to_c1e = true,
1123         .use_acpi = true,
1124 };
1125
1126 static const struct x86_cpu_id intel_idle_ids[] __initconst = {
1127         X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_EP,          &idle_cpu_nhx),
1128         X86_MATCH_INTEL_FAM6_MODEL(NEHALEM,             &idle_cpu_nehalem),
1129         X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_G,           &idle_cpu_nehalem),
1130         X86_MATCH_INTEL_FAM6_MODEL(WESTMERE,            &idle_cpu_nehalem),
1131         X86_MATCH_INTEL_FAM6_MODEL(WESTMERE_EP,         &idle_cpu_nhx),
1132         X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_EX,          &idle_cpu_nhx),
1133         X86_MATCH_INTEL_FAM6_MODEL(ATOM_BONNELL,        &idle_cpu_atom),
1134         X86_MATCH_INTEL_FAM6_MODEL(ATOM_BONNELL_MID,    &idle_cpu_lincroft),
1135         X86_MATCH_INTEL_FAM6_MODEL(WESTMERE_EX,         &idle_cpu_nhx),
1136         X86_MATCH_INTEL_FAM6_MODEL(SANDYBRIDGE,         &idle_cpu_snb),
1137         X86_MATCH_INTEL_FAM6_MODEL(SANDYBRIDGE_X,       &idle_cpu_snx),
1138         X86_MATCH_INTEL_FAM6_MODEL(ATOM_SALTWELL,       &idle_cpu_atom),
1139         X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT,     &idle_cpu_byt),
1140         X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_MID, &idle_cpu_tangier),
1141         X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,        &idle_cpu_cht),
1142         X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE,           &idle_cpu_ivb),
1143         X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE_X,         &idle_cpu_ivt),
1144         X86_MATCH_INTEL_FAM6_MODEL(HASWELL,             &idle_cpu_hsw),
1145         X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X,           &idle_cpu_hsx),
1146         X86_MATCH_INTEL_FAM6_MODEL(HASWELL_L,           &idle_cpu_hsw),
1147         X86_MATCH_INTEL_FAM6_MODEL(HASWELL_G,           &idle_cpu_hsw),
1148         X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D,   &idle_cpu_avn),
1149         X86_MATCH_INTEL_FAM6_MODEL(BROADWELL,           &idle_cpu_bdw),
1150         X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_G,         &idle_cpu_bdw),
1151         X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X,         &idle_cpu_bdx),
1152         X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_D,         &idle_cpu_bdx),
1153         X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L,           &idle_cpu_skl),
1154         X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE,             &idle_cpu_skl),
1155         X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L,          &idle_cpu_skl),
1156         X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE,            &idle_cpu_skl),
1157         X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X,           &idle_cpu_skx),
1158         X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X,           &idle_cpu_icx),
1159         X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL,        &idle_cpu_knl),
1160         X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM,        &idle_cpu_knl),
1161         X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,       &idle_cpu_bxt),
1162         X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_PLUS,  &idle_cpu_bxt),
1163         X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,     &idle_cpu_dnv),
1164         X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D,      &idle_cpu_snr),
1165         {}
1166 };
1167
1168 static const struct x86_cpu_id intel_mwait_ids[] __initconst = {
1169         X86_MATCH_VENDOR_FAM_FEATURE(INTEL, 6, X86_FEATURE_MWAIT, NULL),
1170         {}
1171 };
1172
1173 static bool __init intel_idle_max_cstate_reached(int cstate)
1174 {
1175         if (cstate + 1 > max_cstate) {
1176                 pr_info("max_cstate %d reached\n", max_cstate);
1177                 return true;
1178         }
1179         return false;
1180 }
1181
1182 static bool __init intel_idle_state_needs_timer_stop(struct cpuidle_state *state)
1183 {
1184         unsigned long eax = flg2MWAIT(state->flags);
1185
1186         if (boot_cpu_has(X86_FEATURE_ARAT))
1187                 return false;
1188
1189         /*
1190          * Switch over to one-shot tick broadcast if the target C-state
1191          * is deeper than C1.
1192          */
1193         return !!((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK);
1194 }
1195
1196 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
1197 #include <acpi/processor.h>
1198
1199 static bool no_acpi __read_mostly;
1200 module_param(no_acpi, bool, 0444);
1201 MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list");
1202
1203 static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */
1204 module_param_named(use_acpi, force_use_acpi, bool, 0444);
1205 MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list");
1206
1207 static struct acpi_processor_power acpi_state_table __initdata;
1208
1209 /**
1210  * intel_idle_cst_usable - Check if the _CST information can be used.
1211  *
1212  * Check if all of the C-states listed by _CST in the max_cstate range are
1213  * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT.
1214  */
1215 static bool __init intel_idle_cst_usable(void)
1216 {
1217         int cstate, limit;
1218
1219         limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1),
1220                       acpi_state_table.count);
1221
1222         for (cstate = 1; cstate < limit; cstate++) {
1223                 struct acpi_processor_cx *cx = &acpi_state_table.states[cstate];
1224
1225                 if (cx->entry_method != ACPI_CSTATE_FFH)
1226                         return false;
1227         }
1228
1229         return true;
1230 }
1231
1232 static bool __init intel_idle_acpi_cst_extract(void)
1233 {
1234         unsigned int cpu;
1235
1236         if (no_acpi) {
1237                 pr_debug("Not allowed to use ACPI _CST\n");
1238                 return false;
1239         }
1240
1241         for_each_possible_cpu(cpu) {
1242                 struct acpi_processor *pr = per_cpu(processors, cpu);
1243
1244                 if (!pr)
1245                         continue;
1246
1247                 if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table))
1248                         continue;
1249
1250                 acpi_state_table.count++;
1251
1252                 if (!intel_idle_cst_usable())
1253                         continue;
1254
1255                 if (!acpi_processor_claim_cst_control())
1256                         break;
1257
1258                 return true;
1259         }
1260
1261         acpi_state_table.count = 0;
1262         pr_debug("ACPI _CST not found or not usable\n");
1263         return false;
1264 }
1265
1266 static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
1267 {
1268         int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1269
1270         /*
1271          * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1272          * the interesting states are ACPI_CSTATE_FFH.
1273          */
1274         for (cstate = 1; cstate < limit; cstate++) {
1275                 struct acpi_processor_cx *cx;
1276                 struct cpuidle_state *state;
1277
1278                 if (intel_idle_max_cstate_reached(cstate - 1))
1279                         break;
1280
1281                 cx = &acpi_state_table.states[cstate];
1282
1283                 state = &drv->states[drv->state_count++];
1284
1285                 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate);
1286                 strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
1287                 state->exit_latency = cx->latency;
1288                 /*
1289                  * For C1-type C-states use the same number for both the exit
1290                  * latency and target residency, because that is the case for
1291                  * C1 in the majority of the static C-states tables above.
1292                  * For the other types of C-states, however, set the target
1293                  * residency to 3 times the exit latency which should lead to
1294                  * a reasonable balance between energy-efficiency and
1295                  * performance in the majority of interesting cases.
1296                  */
1297                 state->target_residency = cx->latency;
1298                 if (cx->type > ACPI_STATE_C1)
1299                         state->target_residency *= 3;
1300
1301                 state->flags = MWAIT2flg(cx->address);
1302                 if (cx->type > ACPI_STATE_C2)
1303                         state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
1304
1305                 if (disabled_states_mask & BIT(cstate))
1306                         state->flags |= CPUIDLE_FLAG_OFF;
1307
1308                 if (intel_idle_state_needs_timer_stop(state))
1309                         state->flags |= CPUIDLE_FLAG_TIMER_STOP;
1310
1311                 state->enter = intel_idle;
1312                 state->enter_s2idle = intel_idle_s2idle;
1313         }
1314 }
1315
1316 static bool __init intel_idle_off_by_default(u32 mwait_hint)
1317 {
1318         int cstate, limit;
1319
1320         /*
1321          * If there are no _CST C-states, do not disable any C-states by
1322          * default.
1323          */
1324         if (!acpi_state_table.count)
1325                 return false;
1326
1327         limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1328         /*
1329          * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1330          * the interesting states are ACPI_CSTATE_FFH.
1331          */
1332         for (cstate = 1; cstate < limit; cstate++) {
1333                 if (acpi_state_table.states[cstate].address == mwait_hint)
1334                         return false;
1335         }
1336         return true;
1337 }
1338 #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1339 #define force_use_acpi  (false)
1340
1341 static inline bool intel_idle_acpi_cst_extract(void) { return false; }
1342 static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
1343 static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; }
1344 #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1345
1346 /**
1347  * ivt_idle_state_table_update - Tune the idle states table for Ivy Town.
1348  *
1349  * Tune IVT multi-socket targets.
1350  * Assumption: num_sockets == (max_package_num + 1).
1351  */
1352 static void __init ivt_idle_state_table_update(void)
1353 {
1354         /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1355         int cpu, package_num, num_sockets = 1;
1356
1357         for_each_online_cpu(cpu) {
1358                 package_num = topology_physical_package_id(cpu);
1359                 if (package_num + 1 > num_sockets) {
1360                         num_sockets = package_num + 1;
1361
1362                         if (num_sockets > 4) {
1363                                 cpuidle_state_table = ivt_cstates_8s;
1364                                 return;
1365                         }
1366                 }
1367         }
1368
1369         if (num_sockets > 2)
1370                 cpuidle_state_table = ivt_cstates_4s;
1371
1372         /* else, 1 and 2 socket systems use default ivt_cstates */
1373 }
1374
1375 /**
1376  * irtl_2_usec - IRTL to microseconds conversion.
1377  * @irtl: IRTL MSR value.
1378  *
1379  * Translate the IRTL (Interrupt Response Time Limit) MSR value to microseconds.
1380  */
1381 static unsigned long long __init irtl_2_usec(unsigned long long irtl)
1382 {
1383         static const unsigned int irtl_ns_units[] __initconst = {
1384                 1, 32, 1024, 32768, 1048576, 33554432, 0, 0
1385         };
1386         unsigned long long ns;
1387
1388         if (!irtl)
1389                 return 0;
1390
1391         ns = irtl_ns_units[(irtl >> 10) & 0x7];
1392
1393         return div_u64((irtl & 0x3FF) * ns, NSEC_PER_USEC);
1394 }
1395
1396 /**
1397  * bxt_idle_state_table_update - Fix up the Broxton idle states table.
1398  *
1399  * On BXT, trust the IRTL (Interrupt Response Time Limit) MSR to show the
1400  * definitive maximum latency and use the same value for target_residency.
1401  */
1402 static void __init bxt_idle_state_table_update(void)
1403 {
1404         unsigned long long msr;
1405         unsigned int usec;
1406
1407         rdmsrl(MSR_PKGC6_IRTL, msr);
1408         usec = irtl_2_usec(msr);
1409         if (usec) {
1410                 bxt_cstates[2].exit_latency = usec;
1411                 bxt_cstates[2].target_residency = usec;
1412         }
1413
1414         rdmsrl(MSR_PKGC7_IRTL, msr);
1415         usec = irtl_2_usec(msr);
1416         if (usec) {
1417                 bxt_cstates[3].exit_latency = usec;
1418                 bxt_cstates[3].target_residency = usec;
1419         }
1420
1421         rdmsrl(MSR_PKGC8_IRTL, msr);
1422         usec = irtl_2_usec(msr);
1423         if (usec) {
1424                 bxt_cstates[4].exit_latency = usec;
1425                 bxt_cstates[4].target_residency = usec;
1426         }
1427
1428         rdmsrl(MSR_PKGC9_IRTL, msr);
1429         usec = irtl_2_usec(msr);
1430         if (usec) {
1431                 bxt_cstates[5].exit_latency = usec;
1432                 bxt_cstates[5].target_residency = usec;
1433         }
1434
1435         rdmsrl(MSR_PKGC10_IRTL, msr);
1436         usec = irtl_2_usec(msr);
1437         if (usec) {
1438                 bxt_cstates[6].exit_latency = usec;
1439                 bxt_cstates[6].target_residency = usec;
1440         }
1441
1442 }
1443
1444 /**
1445  * sklh_idle_state_table_update - Fix up the Sky Lake idle states table.
1446  *
1447  * On SKL-H (model 0x5e) skip C8 and C9 if C10 is enabled and SGX disabled.
1448  */
1449 static void __init sklh_idle_state_table_update(void)
1450 {
1451         unsigned long long msr;
1452         unsigned int eax, ebx, ecx, edx;
1453
1454
1455         /* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
1456         if (max_cstate <= 7)
1457                 return;
1458
1459         /* if PC10 not present in CPUID.MWAIT.EDX */
1460         if ((mwait_substates & (0xF << 28)) == 0)
1461                 return;
1462
1463         rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1464
1465         /* PC10 is not enabled in PKG C-state limit */
1466         if ((msr & 0xF) != 8)
1467                 return;
1468
1469         ecx = 0;
1470         cpuid(7, &eax, &ebx, &ecx, &edx);
1471
1472         /* if SGX is present */
1473         if (ebx & (1 << 2)) {
1474
1475                 rdmsrl(MSR_IA32_FEAT_CTL, msr);
1476
1477                 /* if SGX is enabled */
1478                 if (msr & (1 << 18))
1479                         return;
1480         }
1481
1482         skl_cstates[5].flags |= CPUIDLE_FLAG_UNUSABLE;  /* C8-SKL */
1483         skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE;  /* C9-SKL */
1484 }
1485
1486 static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
1487 {
1488         unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
1489         unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
1490                                         MWAIT_SUBSTATE_MASK;
1491
1492         /* Ignore the C-state if there are NO sub-states in CPUID for it. */
1493         if (num_substates == 0)
1494                 return false;
1495
1496         if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1497                 mark_tsc_unstable("TSC halts in idle states deeper than C2");
1498
1499         return true;
1500 }
1501
1502 static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
1503 {
1504         int cstate;
1505
1506         switch (boot_cpu_data.x86_model) {
1507         case INTEL_FAM6_IVYBRIDGE_X:
1508                 ivt_idle_state_table_update();
1509                 break;
1510         case INTEL_FAM6_ATOM_GOLDMONT:
1511         case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
1512                 bxt_idle_state_table_update();
1513                 break;
1514         case INTEL_FAM6_SKYLAKE:
1515                 sklh_idle_state_table_update();
1516                 break;
1517         }
1518
1519         for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
1520                 unsigned int mwait_hint;
1521
1522                 if (intel_idle_max_cstate_reached(cstate))
1523                         break;
1524
1525                 if (!cpuidle_state_table[cstate].enter &&
1526                     !cpuidle_state_table[cstate].enter_s2idle)
1527                         break;
1528
1529                 /* If marked as unusable, skip this state. */
1530                 if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) {
1531                         pr_debug("state %s is disabled\n",
1532                                  cpuidle_state_table[cstate].name);
1533                         continue;
1534                 }
1535
1536                 mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
1537                 if (!intel_idle_verify_cstate(mwait_hint))
1538                         continue;
1539
1540                 /* Structure copy. */
1541                 drv->states[drv->state_count] = cpuidle_state_table[cstate];
1542
1543                 if ((disabled_states_mask & BIT(drv->state_count)) ||
1544                     ((icpu->use_acpi || force_use_acpi) &&
1545                      intel_idle_off_by_default(mwait_hint) &&
1546                      !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)))
1547                         drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF;
1548
1549                 if (intel_idle_state_needs_timer_stop(&drv->states[drv->state_count]))
1550                         drv->states[drv->state_count].flags |= CPUIDLE_FLAG_TIMER_STOP;
1551
1552                 drv->state_count++;
1553         }
1554
1555         if (icpu->byt_auto_demotion_disable_flag) {
1556                 wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
1557                 wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
1558         }
1559 }
1560
1561 /**
1562  * intel_idle_cpuidle_driver_init - Create the list of available idle states.
1563  * @drv: cpuidle driver structure to initialize.
1564  */
1565 static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv)
1566 {
1567         cpuidle_poll_state_init(drv);
1568
1569         if (disabled_states_mask & BIT(0))
1570                 drv->states[0].flags |= CPUIDLE_FLAG_OFF;
1571
1572         drv->state_count = 1;
1573
1574         if (icpu)
1575                 intel_idle_init_cstates_icpu(drv);
1576         else
1577                 intel_idle_init_cstates_acpi(drv);
1578 }
1579
1580 static void auto_demotion_disable(void)
1581 {
1582         unsigned long long msr_bits;
1583
1584         rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1585         msr_bits &= ~auto_demotion_disable_flags;
1586         wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1587 }
1588
1589 static void c1e_promotion_disable(void)
1590 {
1591         unsigned long long msr_bits;
1592
1593         rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
1594         msr_bits &= ~0x2;
1595         wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
1596 }
1597
1598 /**
1599  * intel_idle_cpu_init - Register the target CPU with the cpuidle core.
1600  * @cpu: CPU to initialize.
1601  *
1602  * Register a cpuidle device object for @cpu and update its MSRs in accordance
1603  * with the processor model flags.
1604  */
1605 static int intel_idle_cpu_init(unsigned int cpu)
1606 {
1607         struct cpuidle_device *dev;
1608
1609         dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1610         dev->cpu = cpu;
1611
1612         if (cpuidle_register_device(dev)) {
1613                 pr_debug("cpuidle_register_device %d failed!\n", cpu);
1614                 return -EIO;
1615         }
1616
1617         if (auto_demotion_disable_flags)
1618                 auto_demotion_disable();
1619
1620         if (disable_promotion_to_c1e)
1621                 c1e_promotion_disable();
1622
1623         return 0;
1624 }
1625
1626 static int intel_idle_cpu_online(unsigned int cpu)
1627 {
1628         struct cpuidle_device *dev;
1629
1630         if (!boot_cpu_has(X86_FEATURE_ARAT))
1631                 tick_broadcast_enable();
1632
1633         /*
1634          * Some systems can hotplug a cpu at runtime after
1635          * the kernel has booted, we have to initialize the
1636          * driver in this case
1637          */
1638         dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1639         if (!dev->registered)
1640                 return intel_idle_cpu_init(cpu);
1641
1642         return 0;
1643 }
1644
1645 /**
1646  * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices.
1647  */
1648 static void __init intel_idle_cpuidle_devices_uninit(void)
1649 {
1650         int i;
1651
1652         for_each_online_cpu(i)
1653                 cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i));
1654 }
1655
1656 static int __init intel_idle_init(void)
1657 {
1658         const struct x86_cpu_id *id;
1659         unsigned int eax, ebx, ecx;
1660         int retval;
1661
1662         /* Do not load intel_idle at all for now if idle= is passed */
1663         if (boot_option_idle_override != IDLE_NO_OVERRIDE)
1664                 return -ENODEV;
1665
1666         if (max_cstate == 0) {
1667                 pr_debug("disabled\n");
1668                 return -EPERM;
1669         }
1670
1671         id = x86_match_cpu(intel_idle_ids);
1672         if (id) {
1673                 if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
1674                         pr_debug("Please enable MWAIT in BIOS SETUP\n");
1675                         return -ENODEV;
1676                 }
1677         } else {
1678                 id = x86_match_cpu(intel_mwait_ids);
1679                 if (!id)
1680                         return -ENODEV;
1681         }
1682
1683         if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
1684                 return -ENODEV;
1685
1686         cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
1687
1688         if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
1689             !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
1690             !mwait_substates)
1691                         return -ENODEV;
1692
1693         pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
1694
1695         icpu = (const struct idle_cpu *)id->driver_data;
1696         if (icpu) {
1697                 cpuidle_state_table = icpu->state_table;
1698                 auto_demotion_disable_flags = icpu->auto_demotion_disable_flags;
1699                 disable_promotion_to_c1e = icpu->disable_promotion_to_c1e;
1700                 if (icpu->use_acpi || force_use_acpi)
1701                         intel_idle_acpi_cst_extract();
1702         } else if (!intel_idle_acpi_cst_extract()) {
1703                 return -ENODEV;
1704         }
1705
1706         pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
1707                  boot_cpu_data.x86_model);
1708
1709         intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
1710         if (!intel_idle_cpuidle_devices)
1711                 return -ENOMEM;
1712
1713         intel_idle_cpuidle_driver_init(&intel_idle_driver);
1714
1715         retval = cpuidle_register_driver(&intel_idle_driver);
1716         if (retval) {
1717                 struct cpuidle_driver *drv = cpuidle_get_driver();
1718                 printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"),
1719                        drv ? drv->name : "none");
1720                 goto init_driver_fail;
1721         }
1722
1723         retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online",
1724                                    intel_idle_cpu_online, NULL);
1725         if (retval < 0)
1726                 goto hp_setup_fail;
1727
1728         pr_debug("Local APIC timer is reliable in %s\n",
1729                  boot_cpu_has(X86_FEATURE_ARAT) ? "all C-states" : "C1");
1730
1731         return 0;
1732
1733 hp_setup_fail:
1734         intel_idle_cpuidle_devices_uninit();
1735         cpuidle_unregister_driver(&intel_idle_driver);
1736 init_driver_fail:
1737         free_percpu(intel_idle_cpuidle_devices);
1738         return retval;
1739
1740 }
1741 device_initcall(intel_idle_init);
1742
1743 /*
1744  * We are not really modular, but we used to support that.  Meaning we also
1745  * support "intel_idle.max_cstate=..." at boot and also a read-only export of
1746  * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param
1747  * is the easiest way (currently) to continue doing that.
1748  */
1749 module_param(max_cstate, int, 0444);
1750 /*
1751  * The positions of the bits that are set in this number are the indices of the
1752  * idle states to be disabled by default (as reflected by the names of the
1753  * corresponding idle state directories in sysfs, "state0", "state1" ...
1754  * "state<i>" ..., where <i> is the index of the given state).
1755  */
1756 module_param_named(states_off, disabled_states_mask, uint, 0444);
1757 MODULE_PARM_DESC(states_off, "Mask of disabled idle states");