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
  60static struct cpuidle_driver intel_idle_driver = {
  61	.name = "intel_idle",
  62	.owner = THIS_MODULE,
  63};
  64/* intel_idle.max_cstate=0 disables driver */
  65static int max_cstate = CPUIDLE_STATE_MAX - 1;
  66static unsigned int disabled_states_mask;
  67
  68static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
  69
  70static unsigned long auto_demotion_disable_flags;
  71static bool disable_promotion_to_c1e;
 
  72
  73struct 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
  86static const struct idle_cpu *icpu __initdata;
  87static struct cpuidle_state *cpuidle_state_table __initdata;
  88
  89static 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 */
 123static __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 */
 147static __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 */
 163static 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
 200static 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
 245static 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
 290static 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
 335static 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
 380static 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
 417static 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
 454static 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
 491static 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};
 559static 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
 628static 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
 697static 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
 726static 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 = 170,
 748		.target_residency = 600,
 749		.enter = &intel_idle,
 750		.enter_s2idle = intel_idle_s2idle, },
 751	{
 752		.enter = NULL }
 753};
 754
 755static 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};
 791static 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};
 835static 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};
 855static 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
 876static 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
 937static 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 */
 970static 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
 999static 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
1005static 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
1012static const struct idle_cpu idle_cpu_atom __initconst = {
1013	.state_table = atom_cstates,
1014};
1015
1016static const struct idle_cpu idle_cpu_tangier __initconst = {
1017	.state_table = tangier_cstates,
1018};
1019
1020static 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
1025static const struct idle_cpu idle_cpu_snb __initconst = {
1026	.state_table = snb_cstates,
1027	.disable_promotion_to_c1e = true,
1028};
1029
1030static 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
1036static 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
1042static 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
1048static const struct idle_cpu idle_cpu_ivb __initconst = {
1049	.state_table = ivb_cstates,
1050	.disable_promotion_to_c1e = true,
1051};
1052
1053static 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
1059static const struct idle_cpu idle_cpu_hsw __initconst = {
1060	.state_table = hsw_cstates,
1061	.disable_promotion_to_c1e = true,
1062};
1063
1064static 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
1070static const struct idle_cpu idle_cpu_bdw __initconst = {
1071	.state_table = bdw_cstates,
1072	.disable_promotion_to_c1e = true,
1073};
1074
1075static 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
1081static const struct idle_cpu idle_cpu_skl __initconst = {
1082	.state_table = skl_cstates,
1083	.disable_promotion_to_c1e = true,
1084};
1085
1086static 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
1092static 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
1098static 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
1104static const struct idle_cpu idle_cpu_knl __initconst = {
1105	.state_table = knl_cstates,
1106	.use_acpi = true,
1107};
1108
1109static const struct idle_cpu idle_cpu_bxt __initconst = {
1110	.state_table = bxt_cstates,
1111	.disable_promotion_to_c1e = true,
1112};
1113
1114static 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
1120static 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
1126static 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(ICELAKE_D,		&idle_cpu_icx),
1160	X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL,	&idle_cpu_knl),
1161	X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM,	&idle_cpu_knl),
1162	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT,	&idle_cpu_bxt),
1163	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_PLUS,	&idle_cpu_bxt),
1164	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D,	&idle_cpu_dnv),
1165	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D,	&idle_cpu_snr),
1166	{}
1167};
1168
1169static const struct x86_cpu_id intel_mwait_ids[] __initconst = {
1170	X86_MATCH_VENDOR_FAM_FEATURE(INTEL, 6, X86_FEATURE_MWAIT, NULL),
1171	{}
1172};
1173
1174static bool __init intel_idle_max_cstate_reached(int cstate)
1175{
1176	if (cstate + 1 > max_cstate) {
1177		pr_info("max_cstate %d reached\n", max_cstate);
1178		return true;
1179	}
1180	return false;
1181}
1182
1183static bool __init intel_idle_state_needs_timer_stop(struct cpuidle_state *state)
1184{
1185	unsigned long eax = flg2MWAIT(state->flags);
1186
1187	if (boot_cpu_has(X86_FEATURE_ARAT))
1188		return false;
1189
1190	/*
1191	 * Switch over to one-shot tick broadcast if the target C-state
1192	 * is deeper than C1.
1193	 */
1194	return !!((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK);
1195}
1196
1197#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
1198#include <acpi/processor.h>
1199
1200static bool no_acpi __read_mostly;
1201module_param(no_acpi, bool, 0444);
1202MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list");
1203
1204static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */
1205module_param_named(use_acpi, force_use_acpi, bool, 0444);
1206MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list");
1207
1208static struct acpi_processor_power acpi_state_table __initdata;
1209
1210/**
1211 * intel_idle_cst_usable - Check if the _CST information can be used.
1212 *
1213 * Check if all of the C-states listed by _CST in the max_cstate range are
1214 * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT.
1215 */
1216static bool __init intel_idle_cst_usable(void)
1217{
1218	int cstate, limit;
1219
1220	limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1),
1221		      acpi_state_table.count);
1222
1223	for (cstate = 1; cstate < limit; cstate++) {
1224		struct acpi_processor_cx *cx = &acpi_state_table.states[cstate];
1225
1226		if (cx->entry_method != ACPI_CSTATE_FFH)
1227			return false;
 
1228	}
1229
1230	return true;
1231}
1232
1233static bool __init intel_idle_acpi_cst_extract(void)
1234{
1235	unsigned int cpu;
1236
1237	if (no_acpi) {
1238		pr_debug("Not allowed to use ACPI _CST\n");
1239		return false;
1240	}
1241
1242	for_each_possible_cpu(cpu) {
1243		struct acpi_processor *pr = per_cpu(processors, cpu);
1244
1245		if (!pr)
1246			continue;
1247
1248		if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table))
1249			continue;
1250
1251		acpi_state_table.count++;
1252
1253		if (!intel_idle_cst_usable())
1254			continue;
1255
1256		if (!acpi_processor_claim_cst_control())
1257			break;
1258
1259		return true;
1260	}
1261
1262	acpi_state_table.count = 0;
1263	pr_debug("ACPI _CST not found or not usable\n");
1264	return false;
1265}
1266
1267static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
1268{
1269	int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1270
1271	/*
1272	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1273	 * the interesting states are ACPI_CSTATE_FFH.
1274	 */
1275	for (cstate = 1; cstate < limit; cstate++) {
1276		struct acpi_processor_cx *cx;
1277		struct cpuidle_state *state;
1278
1279		if (intel_idle_max_cstate_reached(cstate - 1))
1280			break;
1281
1282		cx = &acpi_state_table.states[cstate];
1283
1284		state = &drv->states[drv->state_count++];
 
 
 
1285
1286		snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate);
1287		strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
1288		state->exit_latency = cx->latency;
1289		/*
1290		 * For C1-type C-states use the same number for both the exit
1291		 * latency and target residency, because that is the case for
1292		 * C1 in the majority of the static C-states tables above.
1293		 * For the other types of C-states, however, set the target
1294		 * residency to 3 times the exit latency which should lead to
1295		 * a reasonable balance between energy-efficiency and
1296		 * performance in the majority of interesting cases.
1297		 */
1298		state->target_residency = cx->latency;
1299		if (cx->type > ACPI_STATE_C1)
1300			state->target_residency *= 3;
1301
1302		state->flags = MWAIT2flg(cx->address);
1303		if (cx->type > ACPI_STATE_C2)
1304			state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
1305
1306		if (disabled_states_mask & BIT(cstate))
1307			state->flags |= CPUIDLE_FLAG_OFF;
1308
1309		if (intel_idle_state_needs_timer_stop(state))
1310			state->flags |= CPUIDLE_FLAG_TIMER_STOP;
1311
1312		state->enter = intel_idle;
1313		state->enter_s2idle = intel_idle_s2idle;
1314	}
1315}
1316
1317static bool __init intel_idle_off_by_default(u32 mwait_hint)
 
 
 
 
1318{
1319	int cstate, limit;
1320
1321	/*
1322	 * If there are no _CST C-states, do not disable any C-states by
1323	 * default.
1324	 */
1325	if (!acpi_state_table.count)
1326		return false;
1327
1328	limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1329	/*
1330	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1331	 * the interesting states are ACPI_CSTATE_FFH.
1332	 */
1333	for (cstate = 1; cstate < limit; cstate++) {
1334		if (acpi_state_table.states[cstate].address == mwait_hint)
1335			return false;
1336	}
1337	return true;
1338}
1339#else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1340#define force_use_acpi	(false)
1341
1342static inline bool intel_idle_acpi_cst_extract(void) { return false; }
1343static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
1344static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; }
1345#endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1346
1347/**
1348 * ivt_idle_state_table_update - Tune the idle states table for Ivy Town.
1349 *
1350 * Tune IVT multi-socket targets.
1351 * Assumption: num_sockets == (max_package_num + 1).
1352 */
1353static void __init ivt_idle_state_table_update(void)
1354{
1355	/* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1356	int cpu, package_num, num_sockets = 1;
1357
1358	for_each_online_cpu(cpu) {
1359		package_num = topology_physical_package_id(cpu);
1360		if (package_num + 1 > num_sockets) {
1361			num_sockets = package_num + 1;
1362
1363			if (num_sockets > 4) {
1364				cpuidle_state_table = ivt_cstates_8s;
1365				return;
1366			}
1367		}
1368	}
1369
1370	if (num_sockets > 2)
1371		cpuidle_state_table = ivt_cstates_4s;
1372
1373	/* else, 1 and 2 socket systems use default ivt_cstates */
1374}
1375
1376/**
1377 * irtl_2_usec - IRTL to microseconds conversion.
1378 * @irtl: IRTL MSR value.
1379 *
1380 * Translate the IRTL (Interrupt Response Time Limit) MSR value to microseconds.
1381 */
1382static unsigned long long __init irtl_2_usec(unsigned long long irtl)
 
 
 
 
1383{
1384	static const unsigned int irtl_ns_units[] __initconst = {
1385		1, 32, 1024, 32768, 1048576, 33554432, 0, 0
1386	};
1387	unsigned long long ns;
1388
1389	if (!irtl)
1390		return 0;
1391
1392	ns = irtl_ns_units[(irtl >> 10) & 0x7];
1393
1394	return div_u64((irtl & 0x3FF) * ns, NSEC_PER_USEC);
1395}
1396
1397/**
1398 * bxt_idle_state_table_update - Fix up the Broxton idle states table.
1399 *
1400 * On BXT, trust the IRTL (Interrupt Response Time Limit) MSR to show the
1401 * definitive maximum latency and use the same value for target_residency.
1402 */
1403static void __init bxt_idle_state_table_update(void)
1404{
1405	unsigned long long msr;
1406	unsigned int usec;
1407
1408	rdmsrl(MSR_PKGC6_IRTL, msr);
1409	usec = irtl_2_usec(msr);
1410	if (usec) {
1411		bxt_cstates[2].exit_latency = usec;
1412		bxt_cstates[2].target_residency = usec;
1413	}
1414
1415	rdmsrl(MSR_PKGC7_IRTL, msr);
1416	usec = irtl_2_usec(msr);
1417	if (usec) {
1418		bxt_cstates[3].exit_latency = usec;
1419		bxt_cstates[3].target_residency = usec;
1420	}
1421
1422	rdmsrl(MSR_PKGC8_IRTL, msr);
1423	usec = irtl_2_usec(msr);
1424	if (usec) {
1425		bxt_cstates[4].exit_latency = usec;
1426		bxt_cstates[4].target_residency = usec;
1427	}
1428
1429	rdmsrl(MSR_PKGC9_IRTL, msr);
1430	usec = irtl_2_usec(msr);
1431	if (usec) {
1432		bxt_cstates[5].exit_latency = usec;
1433		bxt_cstates[5].target_residency = usec;
1434	}
1435
1436	rdmsrl(MSR_PKGC10_IRTL, msr);
1437	usec = irtl_2_usec(msr);
1438	if (usec) {
1439		bxt_cstates[6].exit_latency = usec;
1440		bxt_cstates[6].target_residency = usec;
1441	}
1442
1443}
1444
1445/**
1446 * sklh_idle_state_table_update - Fix up the Sky Lake idle states table.
1447 *
1448 * On SKL-H (model 0x5e) skip C8 and C9 if C10 is enabled and SGX disabled.
 
1449 */
1450static void __init sklh_idle_state_table_update(void)
1451{
1452	unsigned long long msr;
1453	unsigned int eax, ebx, ecx, edx;
1454
1455
1456	/* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
1457	if (max_cstate <= 7)
1458		return;
1459
1460	/* if PC10 not present in CPUID.MWAIT.EDX */
1461	if ((mwait_substates & (0xF << 28)) == 0)
1462		return;
1463
1464	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1465
1466	/* PC10 is not enabled in PKG C-state limit */
1467	if ((msr & 0xF) != 8)
1468		return;
1469
1470	ecx = 0;
1471	cpuid(7, &eax, &ebx, &ecx, &edx);
1472
1473	/* if SGX is present */
1474	if (ebx & (1 << 2)) {
1475
1476		rdmsrl(MSR_IA32_FEAT_CTL, msr);
1477
1478		/* if SGX is enabled */
1479		if (msr & (1 << 18))
1480			return;
1481	}
1482
1483	skl_cstates[5].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C8-SKL */
1484	skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C9-SKL */
1485}
1486
1487/**
1488 * skx_idle_state_table_update - Adjust the Sky Lake/Cascade Lake
1489 * idle states table.
1490 */
1491static void __init skx_idle_state_table_update(void)
1492{
1493	unsigned long long msr;
1494
1495	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1496
1497	/*
1498	 * 000b: C0/C1 (no package C-state support)
1499	 * 001b: C2
1500	 * 010b: C6 (non-retention)
1501	 * 011b: C6 (retention)
1502	 * 111b: No Package C state limits.
1503	 */
1504	if ((msr & 0x7) < 2) {
1505		/*
1506		 * Uses the CC6 + PC0 latency and 3 times of
1507		 * latency for target_residency if the PC6
1508		 * is disabled in BIOS. This is consistent
1509		 * with how intel_idle driver uses _CST
1510		 * to set the target_residency.
1511		 */
1512		skx_cstates[2].exit_latency = 92;
1513		skx_cstates[2].target_residency = 276;
1514	}
1515}
1516
1517static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
1518{
1519	unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
1520	unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
1521					MWAIT_SUBSTATE_MASK;
1522
1523	/* Ignore the C-state if there are NO sub-states in CPUID for it. */
1524	if (num_substates == 0)
1525		return false;
1526
1527	if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1528		mark_tsc_unstable("TSC halts in idle states deeper than C2");
1529
1530	return true;
1531}
1532
1533static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
1534{
1535	int cstate;
1536
1537	switch (boot_cpu_data.x86_model) {
 
1538	case INTEL_FAM6_IVYBRIDGE_X:
1539		ivt_idle_state_table_update();
1540		break;
1541	case INTEL_FAM6_ATOM_GOLDMONT:
1542	case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
1543		bxt_idle_state_table_update();
1544		break;
1545	case INTEL_FAM6_SKYLAKE:
1546		sklh_idle_state_table_update();
1547		break;
1548	case INTEL_FAM6_SKYLAKE_X:
1549		skx_idle_state_table_update();
1550		break;
1551	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1552
1553	for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
1554		unsigned int mwait_hint;
1555
1556		if (intel_idle_max_cstate_reached(cstate))
 
1557			break;
1558
1559		if (!cpuidle_state_table[cstate].enter &&
1560		    !cpuidle_state_table[cstate].enter_s2idle)
1561			break;
 
 
 
 
 
 
 
 
1562
1563		/* If marked as unusable, skip this state. */
1564		if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) {
 
 
 
 
1565			pr_debug("state %s is disabled\n",
1566				 cpuidle_state_table[cstate].name);
1567			continue;
1568		}
1569
1570		mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
1571		if (!intel_idle_verify_cstate(mwait_hint))
1572			continue;
1573
1574		/* Structure copy. */
1575		drv->states[drv->state_count] = cpuidle_state_table[cstate];
1576
1577		if ((disabled_states_mask & BIT(drv->state_count)) ||
1578		    ((icpu->use_acpi || force_use_acpi) &&
1579		     intel_idle_off_by_default(mwait_hint) &&
1580		     !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)))
1581			drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF;
1582
1583		if (intel_idle_state_needs_timer_stop(&drv->states[drv->state_count]))
1584			drv->states[drv->state_count].flags |= CPUIDLE_FLAG_TIMER_STOP;
1585
1586		drv->state_count++;
1587	}
1588
1589	if (icpu->byt_auto_demotion_disable_flag) {
1590		wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
1591		wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
1592	}
1593}
1594
1595/**
1596 * intel_idle_cpuidle_driver_init - Create the list of available idle states.
1597 * @drv: cpuidle driver structure to initialize.
1598 */
1599static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv)
1600{
1601	cpuidle_poll_state_init(drv);
1602
1603	if (disabled_states_mask & BIT(0))
1604		drv->states[0].flags |= CPUIDLE_FLAG_OFF;
1605
1606	drv->state_count = 1;
1607
1608	if (icpu)
1609		intel_idle_init_cstates_icpu(drv);
1610	else
1611		intel_idle_init_cstates_acpi(drv);
1612}
1613
1614static void auto_demotion_disable(void)
1615{
1616	unsigned long long msr_bits;
1617
1618	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1619	msr_bits &= ~auto_demotion_disable_flags;
1620	wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1621}
1622
1623static void c1e_promotion_disable(void)
1624{
1625	unsigned long long msr_bits;
1626
1627	rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
1628	msr_bits &= ~0x2;
1629	wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
1630}
1631
1632/**
1633 * intel_idle_cpu_init - Register the target CPU with the cpuidle core.
1634 * @cpu: CPU to initialize.
1635 *
1636 * Register a cpuidle device object for @cpu and update its MSRs in accordance
1637 * with the processor model flags.
1638 */
1639static int intel_idle_cpu_init(unsigned int cpu)
1640{
1641	struct cpuidle_device *dev;
1642
1643	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1644	dev->cpu = cpu;
1645
1646	if (cpuidle_register_device(dev)) {
1647		pr_debug("cpuidle_register_device %d failed!\n", cpu);
1648		return -EIO;
1649	}
1650
1651	if (auto_demotion_disable_flags)
1652		auto_demotion_disable();
1653
1654	if (disable_promotion_to_c1e)
1655		c1e_promotion_disable();
1656
1657	return 0;
1658}
1659
1660static int intel_idle_cpu_online(unsigned int cpu)
1661{
1662	struct cpuidle_device *dev;
1663
1664	if (!boot_cpu_has(X86_FEATURE_ARAT))
1665		tick_broadcast_enable();
1666
1667	/*
1668	 * Some systems can hotplug a cpu at runtime after
1669	 * the kernel has booted, we have to initialize the
1670	 * driver in this case
1671	 */
1672	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1673	if (!dev->registered)
1674		return intel_idle_cpu_init(cpu);
1675
1676	return 0;
1677}
1678
1679/**
1680 * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices.
1681 */
1682static void __init intel_idle_cpuidle_devices_uninit(void)
1683{
1684	int i;
1685
1686	for_each_online_cpu(i)
1687		cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i));
1688}
1689
1690static int __init intel_idle_init(void)
1691{
1692	const struct x86_cpu_id *id;
1693	unsigned int eax, ebx, ecx;
1694	int retval;
1695
1696	/* Do not load intel_idle at all for now if idle= is passed */
1697	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
1698		return -ENODEV;
1699
1700	if (max_cstate == 0) {
1701		pr_debug("disabled\n");
1702		return -EPERM;
1703	}
1704
1705	id = x86_match_cpu(intel_idle_ids);
1706	if (id) {
1707		if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
1708			pr_debug("Please enable MWAIT in BIOS SETUP\n");
1709			return -ENODEV;
1710		}
1711	} else {
1712		id = x86_match_cpu(intel_mwait_ids);
1713		if (!id)
1714			return -ENODEV;
1715	}
1716
1717	if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
1718		return -ENODEV;
1719
1720	cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
1721
1722	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
1723	    !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
1724	    !mwait_substates)
1725			return -ENODEV;
1726
1727	pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
1728
1729	icpu = (const struct idle_cpu *)id->driver_data;
1730	if (icpu) {
1731		cpuidle_state_table = icpu->state_table;
1732		auto_demotion_disable_flags = icpu->auto_demotion_disable_flags;
1733		disable_promotion_to_c1e = icpu->disable_promotion_to_c1e;
1734		if (icpu->use_acpi || force_use_acpi)
1735			intel_idle_acpi_cst_extract();
1736	} else if (!intel_idle_acpi_cst_extract()) {
1737		return -ENODEV;
1738	}
1739
1740	pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
1741		 boot_cpu_data.x86_model);
1742
1743	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
1744	if (!intel_idle_cpuidle_devices)
1745		return -ENOMEM;
1746
1747	intel_idle_cpuidle_driver_init(&intel_idle_driver);
1748
1749	retval = cpuidle_register_driver(&intel_idle_driver);
1750	if (retval) {
1751		struct cpuidle_driver *drv = cpuidle_get_driver();
1752		printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"),
1753		       drv ? drv->name : "none");
1754		goto init_driver_fail;
1755	}
1756
 
 
 
1757	retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online",
1758				   intel_idle_cpu_online, NULL);
1759	if (retval < 0)
1760		goto hp_setup_fail;
1761
1762	pr_debug("Local APIC timer is reliable in %s\n",
1763		 boot_cpu_has(X86_FEATURE_ARAT) ? "all C-states" : "C1");
1764
1765	return 0;
1766
1767hp_setup_fail:
1768	intel_idle_cpuidle_devices_uninit();
1769	cpuidle_unregister_driver(&intel_idle_driver);
1770init_driver_fail:
1771	free_percpu(intel_idle_cpuidle_devices);
1772	return retval;
1773
1774}
1775device_initcall(intel_idle_init);
1776
1777/*
1778 * We are not really modular, but we used to support that.  Meaning we also
1779 * support "intel_idle.max_cstate=..." at boot and also a read-only export of
1780 * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param
1781 * is the easiest way (currently) to continue doing that.
1782 */
1783module_param(max_cstate, int, 0444);
1784/*
1785 * The positions of the bits that are set in this number are the indices of the
1786 * idle states to be disabled by default (as reflected by the names of the
1787 * corresponding idle state directories in sysfs, "state0", "state1" ...
1788 * "state<i>" ..., where <i> is the index of the given state).
1789 */
1790module_param_named(states_off, disabled_states_mask, uint, 0444);
1791MODULE_PARM_DESC(states_off, "Mask of disabled idle states");