1 /* 2 * intel_idle.c - native hardware idle loop for modern Intel processors 3 * 4 * Copyright (c) 2013, Intel Corporation. 5 * Len Brown <len.brown@intel.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms and conditions of the GNU General Public License, 9 * version 2, as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program; if not, write to the Free Software Foundation, Inc., 18 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 19 */ 20 21 /* 22 * intel_idle is a cpuidle driver that loads on specific Intel processors 23 * in lieu of the legacy ACPI processor_idle driver. The intent is to 24 * make Linux more efficient on these processors, as intel_idle knows 25 * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. 26 */ 27 28 /* 29 * Design Assumptions 30 * 31 * All CPUs have same idle states as boot CPU 32 * 33 * Chipset BM_STS (bus master status) bit is a NOP 34 * for preventing entry into deep C-stats 35 */ 36 37 /* 38 * Known limitations 39 * 40 * The driver currently initializes for_each_online_cpu() upon modprobe. 41 * It it unaware of subsequent processors hot-added to the system. 42 * This means that if you boot with maxcpus=n and later online 43 * processors above n, those processors will use C1 only. 44 * 45 * ACPI has a .suspend hack to turn off deep c-statees during suspend 46 * to avoid complications with the lapic timer workaround. 47 * Have not seen issues with suspend, but may need same workaround here. 48 * 49 * There is currently no kernel-based automatic probing/loading mechanism 50 * if the driver is built as a module. 51 */ 52 53 /* un-comment DEBUG to enable pr_debug() statements */ 54 #define DEBUG 55 56 #include <linux/kernel.h> 57 #include <linux/cpuidle.h> 58 #include <linux/tick.h> 59 #include <trace/events/power.h> 60 #include <linux/sched.h> 61 #include <linux/notifier.h> 62 #include <linux/cpu.h> 63 #include <linux/module.h> 64 #include <asm/cpu_device_id.h> 65 #include <asm/mwait.h> 66 #include <asm/msr.h> 67 68 #define INTEL_IDLE_VERSION "0.4" 69 #define PREFIX "intel_idle: " 70 71 static struct cpuidle_driver intel_idle_driver = { 72 .name = "intel_idle", 73 .owner = THIS_MODULE, 74 }; 75 /* intel_idle.max_cstate=0 disables driver */ 76 static int max_cstate = CPUIDLE_STATE_MAX - 1; 77 78 static unsigned int mwait_substates; 79 80 #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF 81 /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ 82 static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ 83 84 struct idle_cpu { 85 struct cpuidle_state *state_table; 86 87 /* 88 * Hardware C-state auto-demotion may not always be optimal. 89 * Indicate which enable bits to clear here. 90 */ 91 unsigned long auto_demotion_disable_flags; 92 bool byt_auto_demotion_disable_flag; 93 bool disable_promotion_to_c1e; 94 }; 95 96 static const struct idle_cpu *icpu; 97 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; 98 static int intel_idle(struct cpuidle_device *dev, 99 struct cpuidle_driver *drv, int index); 100 static void intel_idle_freeze(struct cpuidle_device *dev, 101 struct cpuidle_driver *drv, int index); 102 static int intel_idle_cpu_init(int cpu); 103 104 static struct cpuidle_state *cpuidle_state_table; 105 106 /* 107 * Set this flag for states where the HW flushes the TLB for us 108 * and so we don't need cross-calls to keep it consistent. 109 * If this flag is set, SW flushes the TLB, so even if the 110 * HW doesn't do the flushing, this flag is safe to use. 111 */ 112 #define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 113 114 /* 115 * MWAIT takes an 8-bit "hint" in EAX "suggesting" 116 * the C-state (top nibble) and sub-state (bottom nibble) 117 * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc. 118 * 119 * We store the hint at the top of our "flags" for each state. 120 */ 121 #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF) 122 #define MWAIT2flg(eax) ((eax & 0xFF) << 24) 123 124 /* 125 * States are indexed by the cstate number, 126 * which is also the index into the MWAIT hint array. 127 * Thus C0 is a dummy. 128 */ 129 static struct cpuidle_state nehalem_cstates[] = { 130 { 131 .name = "C1-NHM", 132 .desc = "MWAIT 0x00", 133 .flags = MWAIT2flg(0x00), 134 .exit_latency = 3, 135 .target_residency = 6, 136 .enter = &intel_idle, 137 .enter_freeze = intel_idle_freeze, }, 138 { 139 .name = "C1E-NHM", 140 .desc = "MWAIT 0x01", 141 .flags = MWAIT2flg(0x01), 142 .exit_latency = 10, 143 .target_residency = 20, 144 .enter = &intel_idle, 145 .enter_freeze = intel_idle_freeze, }, 146 { 147 .name = "C3-NHM", 148 .desc = "MWAIT 0x10", 149 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 150 .exit_latency = 20, 151 .target_residency = 80, 152 .enter = &intel_idle, 153 .enter_freeze = intel_idle_freeze, }, 154 { 155 .name = "C6-NHM", 156 .desc = "MWAIT 0x20", 157 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 158 .exit_latency = 200, 159 .target_residency = 800, 160 .enter = &intel_idle, 161 .enter_freeze = intel_idle_freeze, }, 162 { 163 .enter = NULL } 164 }; 165 166 static struct cpuidle_state snb_cstates[] = { 167 { 168 .name = "C1-SNB", 169 .desc = "MWAIT 0x00", 170 .flags = MWAIT2flg(0x00), 171 .exit_latency = 2, 172 .target_residency = 2, 173 .enter = &intel_idle, 174 .enter_freeze = intel_idle_freeze, }, 175 { 176 .name = "C1E-SNB", 177 .desc = "MWAIT 0x01", 178 .flags = MWAIT2flg(0x01), 179 .exit_latency = 10, 180 .target_residency = 20, 181 .enter = &intel_idle, 182 .enter_freeze = intel_idle_freeze, }, 183 { 184 .name = "C3-SNB", 185 .desc = "MWAIT 0x10", 186 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 187 .exit_latency = 80, 188 .target_residency = 211, 189 .enter = &intel_idle, 190 .enter_freeze = intel_idle_freeze, }, 191 { 192 .name = "C6-SNB", 193 .desc = "MWAIT 0x20", 194 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 195 .exit_latency = 104, 196 .target_residency = 345, 197 .enter = &intel_idle, 198 .enter_freeze = intel_idle_freeze, }, 199 { 200 .name = "C7-SNB", 201 .desc = "MWAIT 0x30", 202 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, 203 .exit_latency = 109, 204 .target_residency = 345, 205 .enter = &intel_idle, 206 .enter_freeze = intel_idle_freeze, }, 207 { 208 .enter = NULL } 209 }; 210 211 static struct cpuidle_state byt_cstates[] = { 212 { 213 .name = "C1-BYT", 214 .desc = "MWAIT 0x00", 215 .flags = MWAIT2flg(0x00), 216 .exit_latency = 1, 217 .target_residency = 1, 218 .enter = &intel_idle, 219 .enter_freeze = intel_idle_freeze, }, 220 { 221 .name = "C6N-BYT", 222 .desc = "MWAIT 0x58", 223 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, 224 .exit_latency = 300, 225 .target_residency = 275, 226 .enter = &intel_idle, 227 .enter_freeze = intel_idle_freeze, }, 228 { 229 .name = "C6S-BYT", 230 .desc = "MWAIT 0x52", 231 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, 232 .exit_latency = 500, 233 .target_residency = 560, 234 .enter = &intel_idle, 235 .enter_freeze = intel_idle_freeze, }, 236 { 237 .name = "C7-BYT", 238 .desc = "MWAIT 0x60", 239 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, 240 .exit_latency = 1200, 241 .target_residency = 4000, 242 .enter = &intel_idle, 243 .enter_freeze = intel_idle_freeze, }, 244 { 245 .name = "C7S-BYT", 246 .desc = "MWAIT 0x64", 247 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, 248 .exit_latency = 10000, 249 .target_residency = 20000, 250 .enter = &intel_idle, 251 .enter_freeze = intel_idle_freeze, }, 252 { 253 .enter = NULL } 254 }; 255 256 static struct cpuidle_state cht_cstates[] = { 257 { 258 .name = "C1-CHT", 259 .desc = "MWAIT 0x00", 260 .flags = MWAIT2flg(0x00), 261 .exit_latency = 1, 262 .target_residency = 1, 263 .enter = &intel_idle, 264 .enter_freeze = intel_idle_freeze, }, 265 { 266 .name = "C6N-CHT", 267 .desc = "MWAIT 0x58", 268 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED, 269 .exit_latency = 80, 270 .target_residency = 275, 271 .enter = &intel_idle, 272 .enter_freeze = intel_idle_freeze, }, 273 { 274 .name = "C6S-CHT", 275 .desc = "MWAIT 0x52", 276 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, 277 .exit_latency = 200, 278 .target_residency = 560, 279 .enter = &intel_idle, 280 .enter_freeze = intel_idle_freeze, }, 281 { 282 .name = "C7-CHT", 283 .desc = "MWAIT 0x60", 284 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, 285 .exit_latency = 1200, 286 .target_residency = 4000, 287 .enter = &intel_idle, 288 .enter_freeze = intel_idle_freeze, }, 289 { 290 .name = "C7S-CHT", 291 .desc = "MWAIT 0x64", 292 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED, 293 .exit_latency = 10000, 294 .target_residency = 20000, 295 .enter = &intel_idle, 296 .enter_freeze = intel_idle_freeze, }, 297 { 298 .enter = NULL } 299 }; 300 301 static struct cpuidle_state ivb_cstates[] = { 302 { 303 .name = "C1-IVB", 304 .desc = "MWAIT 0x00", 305 .flags = MWAIT2flg(0x00), 306 .exit_latency = 1, 307 .target_residency = 1, 308 .enter = &intel_idle, 309 .enter_freeze = intel_idle_freeze, }, 310 { 311 .name = "C1E-IVB", 312 .desc = "MWAIT 0x01", 313 .flags = MWAIT2flg(0x01), 314 .exit_latency = 10, 315 .target_residency = 20, 316 .enter = &intel_idle, 317 .enter_freeze = intel_idle_freeze, }, 318 { 319 .name = "C3-IVB", 320 .desc = "MWAIT 0x10", 321 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 322 .exit_latency = 59, 323 .target_residency = 156, 324 .enter = &intel_idle, 325 .enter_freeze = intel_idle_freeze, }, 326 { 327 .name = "C6-IVB", 328 .desc = "MWAIT 0x20", 329 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 330 .exit_latency = 80, 331 .target_residency = 300, 332 .enter = &intel_idle, 333 .enter_freeze = intel_idle_freeze, }, 334 { 335 .name = "C7-IVB", 336 .desc = "MWAIT 0x30", 337 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, 338 .exit_latency = 87, 339 .target_residency = 300, 340 .enter = &intel_idle, 341 .enter_freeze = intel_idle_freeze, }, 342 { 343 .enter = NULL } 344 }; 345 346 static struct cpuidle_state ivt_cstates[] = { 347 { 348 .name = "C1-IVT", 349 .desc = "MWAIT 0x00", 350 .flags = MWAIT2flg(0x00), 351 .exit_latency = 1, 352 .target_residency = 1, 353 .enter = &intel_idle, 354 .enter_freeze = intel_idle_freeze, }, 355 { 356 .name = "C1E-IVT", 357 .desc = "MWAIT 0x01", 358 .flags = MWAIT2flg(0x01), 359 .exit_latency = 10, 360 .target_residency = 80, 361 .enter = &intel_idle, 362 .enter_freeze = intel_idle_freeze, }, 363 { 364 .name = "C3-IVT", 365 .desc = "MWAIT 0x10", 366 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 367 .exit_latency = 59, 368 .target_residency = 156, 369 .enter = &intel_idle, 370 .enter_freeze = intel_idle_freeze, }, 371 { 372 .name = "C6-IVT", 373 .desc = "MWAIT 0x20", 374 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 375 .exit_latency = 82, 376 .target_residency = 300, 377 .enter = &intel_idle, 378 .enter_freeze = intel_idle_freeze, }, 379 { 380 .enter = NULL } 381 }; 382 383 static struct cpuidle_state ivt_cstates_4s[] = { 384 { 385 .name = "C1-IVT-4S", 386 .desc = "MWAIT 0x00", 387 .flags = MWAIT2flg(0x00), 388 .exit_latency = 1, 389 .target_residency = 1, 390 .enter = &intel_idle, 391 .enter_freeze = intel_idle_freeze, }, 392 { 393 .name = "C1E-IVT-4S", 394 .desc = "MWAIT 0x01", 395 .flags = MWAIT2flg(0x01), 396 .exit_latency = 10, 397 .target_residency = 250, 398 .enter = &intel_idle, 399 .enter_freeze = intel_idle_freeze, }, 400 { 401 .name = "C3-IVT-4S", 402 .desc = "MWAIT 0x10", 403 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 404 .exit_latency = 59, 405 .target_residency = 300, 406 .enter = &intel_idle, 407 .enter_freeze = intel_idle_freeze, }, 408 { 409 .name = "C6-IVT-4S", 410 .desc = "MWAIT 0x20", 411 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 412 .exit_latency = 84, 413 .target_residency = 400, 414 .enter = &intel_idle, 415 .enter_freeze = intel_idle_freeze, }, 416 { 417 .enter = NULL } 418 }; 419 420 static struct cpuidle_state ivt_cstates_8s[] = { 421 { 422 .name = "C1-IVT-8S", 423 .desc = "MWAIT 0x00", 424 .flags = MWAIT2flg(0x00), 425 .exit_latency = 1, 426 .target_residency = 1, 427 .enter = &intel_idle, 428 .enter_freeze = intel_idle_freeze, }, 429 { 430 .name = "C1E-IVT-8S", 431 .desc = "MWAIT 0x01", 432 .flags = MWAIT2flg(0x01), 433 .exit_latency = 10, 434 .target_residency = 500, 435 .enter = &intel_idle, 436 .enter_freeze = intel_idle_freeze, }, 437 { 438 .name = "C3-IVT-8S", 439 .desc = "MWAIT 0x10", 440 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 441 .exit_latency = 59, 442 .target_residency = 600, 443 .enter = &intel_idle, 444 .enter_freeze = intel_idle_freeze, }, 445 { 446 .name = "C6-IVT-8S", 447 .desc = "MWAIT 0x20", 448 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 449 .exit_latency = 88, 450 .target_residency = 700, 451 .enter = &intel_idle, 452 .enter_freeze = intel_idle_freeze, }, 453 { 454 .enter = NULL } 455 }; 456 457 static struct cpuidle_state hsw_cstates[] = { 458 { 459 .name = "C1-HSW", 460 .desc = "MWAIT 0x00", 461 .flags = MWAIT2flg(0x00), 462 .exit_latency = 2, 463 .target_residency = 2, 464 .enter = &intel_idle, 465 .enter_freeze = intel_idle_freeze, }, 466 { 467 .name = "C1E-HSW", 468 .desc = "MWAIT 0x01", 469 .flags = MWAIT2flg(0x01), 470 .exit_latency = 10, 471 .target_residency = 20, 472 .enter = &intel_idle, 473 .enter_freeze = intel_idle_freeze, }, 474 { 475 .name = "C3-HSW", 476 .desc = "MWAIT 0x10", 477 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 478 .exit_latency = 33, 479 .target_residency = 100, 480 .enter = &intel_idle, 481 .enter_freeze = intel_idle_freeze, }, 482 { 483 .name = "C6-HSW", 484 .desc = "MWAIT 0x20", 485 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 486 .exit_latency = 133, 487 .target_residency = 400, 488 .enter = &intel_idle, 489 .enter_freeze = intel_idle_freeze, }, 490 { 491 .name = "C7s-HSW", 492 .desc = "MWAIT 0x32", 493 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, 494 .exit_latency = 166, 495 .target_residency = 500, 496 .enter = &intel_idle, 497 .enter_freeze = intel_idle_freeze, }, 498 { 499 .name = "C8-HSW", 500 .desc = "MWAIT 0x40", 501 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, 502 .exit_latency = 300, 503 .target_residency = 900, 504 .enter = &intel_idle, 505 .enter_freeze = intel_idle_freeze, }, 506 { 507 .name = "C9-HSW", 508 .desc = "MWAIT 0x50", 509 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, 510 .exit_latency = 600, 511 .target_residency = 1800, 512 .enter = &intel_idle, 513 .enter_freeze = intel_idle_freeze, }, 514 { 515 .name = "C10-HSW", 516 .desc = "MWAIT 0x60", 517 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, 518 .exit_latency = 2600, 519 .target_residency = 7700, 520 .enter = &intel_idle, 521 .enter_freeze = intel_idle_freeze, }, 522 { 523 .enter = NULL } 524 }; 525 static struct cpuidle_state bdw_cstates[] = { 526 { 527 .name = "C1-BDW", 528 .desc = "MWAIT 0x00", 529 .flags = MWAIT2flg(0x00), 530 .exit_latency = 2, 531 .target_residency = 2, 532 .enter = &intel_idle, 533 .enter_freeze = intel_idle_freeze, }, 534 { 535 .name = "C1E-BDW", 536 .desc = "MWAIT 0x01", 537 .flags = MWAIT2flg(0x01), 538 .exit_latency = 10, 539 .target_residency = 20, 540 .enter = &intel_idle, 541 .enter_freeze = intel_idle_freeze, }, 542 { 543 .name = "C3-BDW", 544 .desc = "MWAIT 0x10", 545 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 546 .exit_latency = 40, 547 .target_residency = 100, 548 .enter = &intel_idle, 549 .enter_freeze = intel_idle_freeze, }, 550 { 551 .name = "C6-BDW", 552 .desc = "MWAIT 0x20", 553 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 554 .exit_latency = 133, 555 .target_residency = 400, 556 .enter = &intel_idle, 557 .enter_freeze = intel_idle_freeze, }, 558 { 559 .name = "C7s-BDW", 560 .desc = "MWAIT 0x32", 561 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED, 562 .exit_latency = 166, 563 .target_residency = 500, 564 .enter = &intel_idle, 565 .enter_freeze = intel_idle_freeze, }, 566 { 567 .name = "C8-BDW", 568 .desc = "MWAIT 0x40", 569 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, 570 .exit_latency = 300, 571 .target_residency = 900, 572 .enter = &intel_idle, 573 .enter_freeze = intel_idle_freeze, }, 574 { 575 .name = "C9-BDW", 576 .desc = "MWAIT 0x50", 577 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, 578 .exit_latency = 600, 579 .target_residency = 1800, 580 .enter = &intel_idle, 581 .enter_freeze = intel_idle_freeze, }, 582 { 583 .name = "C10-BDW", 584 .desc = "MWAIT 0x60", 585 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, 586 .exit_latency = 2600, 587 .target_residency = 7700, 588 .enter = &intel_idle, 589 .enter_freeze = intel_idle_freeze, }, 590 { 591 .enter = NULL } 592 }; 593 594 static struct cpuidle_state skl_cstates[] = { 595 { 596 .name = "C1-SKL", 597 .desc = "MWAIT 0x00", 598 .flags = MWAIT2flg(0x00), 599 .exit_latency = 2, 600 .target_residency = 2, 601 .enter = &intel_idle, 602 .enter_freeze = intel_idle_freeze, }, 603 { 604 .name = "C1E-SKL", 605 .desc = "MWAIT 0x01", 606 .flags = MWAIT2flg(0x01), 607 .exit_latency = 10, 608 .target_residency = 20, 609 .enter = &intel_idle, 610 .enter_freeze = intel_idle_freeze, }, 611 { 612 .name = "C3-SKL", 613 .desc = "MWAIT 0x10", 614 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED, 615 .exit_latency = 70, 616 .target_residency = 100, 617 .enter = &intel_idle, 618 .enter_freeze = intel_idle_freeze, }, 619 { 620 .name = "C6-SKL", 621 .desc = "MWAIT 0x20", 622 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, 623 .exit_latency = 85, 624 .target_residency = 200, 625 .enter = &intel_idle, 626 .enter_freeze = intel_idle_freeze, }, 627 { 628 .name = "C7s-SKL", 629 .desc = "MWAIT 0x33", 630 .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED, 631 .exit_latency = 124, 632 .target_residency = 800, 633 .enter = &intel_idle, 634 .enter_freeze = intel_idle_freeze, }, 635 { 636 .name = "C8-SKL", 637 .desc = "MWAIT 0x40", 638 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, 639 .exit_latency = 200, 640 .target_residency = 800, 641 .enter = &intel_idle, 642 .enter_freeze = intel_idle_freeze, }, 643 { 644 .name = "C9-SKL", 645 .desc = "MWAIT 0x50", 646 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, 647 .exit_latency = 480, 648 .target_residency = 5000, 649 .enter = &intel_idle, 650 .enter_freeze = intel_idle_freeze, }, 651 { 652 .name = "C10-SKL", 653 .desc = "MWAIT 0x60", 654 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, 655 .exit_latency = 890, 656 .target_residency = 5000, 657 .enter = &intel_idle, 658 .enter_freeze = intel_idle_freeze, }, 659 { 660 .enter = NULL } 661 }; 662 663 static struct cpuidle_state atom_cstates[] = { 664 { 665 .name = "C1E-ATM", 666 .desc = "MWAIT 0x00", 667 .flags = MWAIT2flg(0x00), 668 .exit_latency = 10, 669 .target_residency = 20, 670 .enter = &intel_idle, 671 .enter_freeze = intel_idle_freeze, }, 672 { 673 .name = "C2-ATM", 674 .desc = "MWAIT 0x10", 675 .flags = MWAIT2flg(0x10), 676 .exit_latency = 20, 677 .target_residency = 80, 678 .enter = &intel_idle, 679 .enter_freeze = intel_idle_freeze, }, 680 { 681 .name = "C4-ATM", 682 .desc = "MWAIT 0x30", 683 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED, 684 .exit_latency = 100, 685 .target_residency = 400, 686 .enter = &intel_idle, 687 .enter_freeze = intel_idle_freeze, }, 688 { 689 .name = "C6-ATM", 690 .desc = "MWAIT 0x52", 691 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED, 692 .exit_latency = 140, 693 .target_residency = 560, 694 .enter = &intel_idle, 695 .enter_freeze = intel_idle_freeze, }, 696 { 697 .enter = NULL } 698 }; 699 static struct cpuidle_state avn_cstates[] = { 700 { 701 .name = "C1-AVN", 702 .desc = "MWAIT 0x00", 703 .flags = MWAIT2flg(0x00), 704 .exit_latency = 2, 705 .target_residency = 2, 706 .enter = &intel_idle, 707 .enter_freeze = intel_idle_freeze, }, 708 { 709 .name = "C6-AVN", 710 .desc = "MWAIT 0x51", 711 .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED, 712 .exit_latency = 15, 713 .target_residency = 45, 714 .enter = &intel_idle, 715 .enter_freeze = intel_idle_freeze, }, 716 { 717 .enter = NULL } 718 }; 719 720 /** 721 * intel_idle 722 * @dev: cpuidle_device 723 * @drv: cpuidle driver 724 * @index: index of cpuidle state 725 * 726 * Must be called under local_irq_disable(). 727 */ 728 static int intel_idle(struct cpuidle_device *dev, 729 struct cpuidle_driver *drv, int index) 730 { 731 unsigned long ecx = 1; /* break on interrupt flag */ 732 struct cpuidle_state *state = &drv->states[index]; 733 unsigned long eax = flg2MWAIT(state->flags); 734 unsigned int cstate; 735 int cpu = smp_processor_id(); 736 737 cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; 738 739 /* 740 * leave_mm() to avoid costly and often unnecessary wakeups 741 * for flushing the user TLB's associated with the active mm. 742 */ 743 if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) 744 leave_mm(cpu); 745 746 if (!(lapic_timer_reliable_states & (1 << (cstate)))) 747 tick_broadcast_enter(); 748 749 mwait_idle_with_hints(eax, ecx); 750 751 if (!(lapic_timer_reliable_states & (1 << (cstate)))) 752 tick_broadcast_exit(); 753 754 return index; 755 } 756 757 /** 758 * intel_idle_freeze - simplified "enter" callback routine for suspend-to-idle 759 * @dev: cpuidle_device 760 * @drv: cpuidle driver 761 * @index: state index 762 */ 763 static void intel_idle_freeze(struct cpuidle_device *dev, 764 struct cpuidle_driver *drv, int index) 765 { 766 unsigned long ecx = 1; /* break on interrupt flag */ 767 unsigned long eax = flg2MWAIT(drv->states[index].flags); 768 769 mwait_idle_with_hints(eax, ecx); 770 } 771 772 static void __setup_broadcast_timer(void *arg) 773 { 774 unsigned long on = (unsigned long)arg; 775 776 if (on) 777 tick_broadcast_enable(); 778 else 779 tick_broadcast_disable(); 780 } 781 782 static int cpu_hotplug_notify(struct notifier_block *n, 783 unsigned long action, void *hcpu) 784 { 785 int hotcpu = (unsigned long)hcpu; 786 struct cpuidle_device *dev; 787 788 switch (action & ~CPU_TASKS_FROZEN) { 789 case CPU_ONLINE: 790 791 if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) 792 smp_call_function_single(hotcpu, __setup_broadcast_timer, 793 (void *)true, 1); 794 795 /* 796 * Some systems can hotplug a cpu at runtime after 797 * the kernel has booted, we have to initialize the 798 * driver in this case 799 */ 800 dev = per_cpu_ptr(intel_idle_cpuidle_devices, hotcpu); 801 if (!dev->registered) 802 intel_idle_cpu_init(hotcpu); 803 804 break; 805 } 806 return NOTIFY_OK; 807 } 808 809 static struct notifier_block cpu_hotplug_notifier = { 810 .notifier_call = cpu_hotplug_notify, 811 }; 812 813 static void auto_demotion_disable(void *dummy) 814 { 815 unsigned long long msr_bits; 816 817 rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); 818 msr_bits &= ~(icpu->auto_demotion_disable_flags); 819 wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); 820 } 821 static void c1e_promotion_disable(void *dummy) 822 { 823 unsigned long long msr_bits; 824 825 rdmsrl(MSR_IA32_POWER_CTL, msr_bits); 826 msr_bits &= ~0x2; 827 wrmsrl(MSR_IA32_POWER_CTL, msr_bits); 828 } 829 830 static const struct idle_cpu idle_cpu_nehalem = { 831 .state_table = nehalem_cstates, 832 .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, 833 .disable_promotion_to_c1e = true, 834 }; 835 836 static const struct idle_cpu idle_cpu_atom = { 837 .state_table = atom_cstates, 838 }; 839 840 static const struct idle_cpu idle_cpu_lincroft = { 841 .state_table = atom_cstates, 842 .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE, 843 }; 844 845 static const struct idle_cpu idle_cpu_snb = { 846 .state_table = snb_cstates, 847 .disable_promotion_to_c1e = true, 848 }; 849 850 static const struct idle_cpu idle_cpu_byt = { 851 .state_table = byt_cstates, 852 .disable_promotion_to_c1e = true, 853 .byt_auto_demotion_disable_flag = true, 854 }; 855 856 static const struct idle_cpu idle_cpu_cht = { 857 .state_table = cht_cstates, 858 .disable_promotion_to_c1e = true, 859 .byt_auto_demotion_disable_flag = true, 860 }; 861 862 static const struct idle_cpu idle_cpu_ivb = { 863 .state_table = ivb_cstates, 864 .disable_promotion_to_c1e = true, 865 }; 866 867 static const struct idle_cpu idle_cpu_ivt = { 868 .state_table = ivt_cstates, 869 .disable_promotion_to_c1e = true, 870 }; 871 872 static const struct idle_cpu idle_cpu_hsw = { 873 .state_table = hsw_cstates, 874 .disable_promotion_to_c1e = true, 875 }; 876 877 static const struct idle_cpu idle_cpu_bdw = { 878 .state_table = bdw_cstates, 879 .disable_promotion_to_c1e = true, 880 }; 881 882 static const struct idle_cpu idle_cpu_skl = { 883 .state_table = skl_cstates, 884 .disable_promotion_to_c1e = true, 885 }; 886 887 888 static const struct idle_cpu idle_cpu_avn = { 889 .state_table = avn_cstates, 890 .disable_promotion_to_c1e = true, 891 }; 892 893 #define ICPU(model, cpu) \ 894 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu } 895 896 static const struct x86_cpu_id intel_idle_ids[] __initconst = { 897 ICPU(0x1a, idle_cpu_nehalem), 898 ICPU(0x1e, idle_cpu_nehalem), 899 ICPU(0x1f, idle_cpu_nehalem), 900 ICPU(0x25, idle_cpu_nehalem), 901 ICPU(0x2c, idle_cpu_nehalem), 902 ICPU(0x2e, idle_cpu_nehalem), 903 ICPU(0x1c, idle_cpu_atom), 904 ICPU(0x26, idle_cpu_lincroft), 905 ICPU(0x2f, idle_cpu_nehalem), 906 ICPU(0x2a, idle_cpu_snb), 907 ICPU(0x2d, idle_cpu_snb), 908 ICPU(0x36, idle_cpu_atom), 909 ICPU(0x37, idle_cpu_byt), 910 ICPU(0x4c, idle_cpu_cht), 911 ICPU(0x3a, idle_cpu_ivb), 912 ICPU(0x3e, idle_cpu_ivt), 913 ICPU(0x3c, idle_cpu_hsw), 914 ICPU(0x3f, idle_cpu_hsw), 915 ICPU(0x45, idle_cpu_hsw), 916 ICPU(0x46, idle_cpu_hsw), 917 ICPU(0x4d, idle_cpu_avn), 918 ICPU(0x3d, idle_cpu_bdw), 919 ICPU(0x47, idle_cpu_bdw), 920 ICPU(0x4f, idle_cpu_bdw), 921 ICPU(0x56, idle_cpu_bdw), 922 ICPU(0x4e, idle_cpu_skl), 923 ICPU(0x5e, idle_cpu_skl), 924 {} 925 }; 926 MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids); 927 928 /* 929 * intel_idle_probe() 930 */ 931 static int __init intel_idle_probe(void) 932 { 933 unsigned int eax, ebx, ecx; 934 const struct x86_cpu_id *id; 935 936 if (max_cstate == 0) { 937 pr_debug(PREFIX "disabled\n"); 938 return -EPERM; 939 } 940 941 id = x86_match_cpu(intel_idle_ids); 942 if (!id) { 943 if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && 944 boot_cpu_data.x86 == 6) 945 pr_debug(PREFIX "does not run on family %d model %d\n", 946 boot_cpu_data.x86, boot_cpu_data.x86_model); 947 return -ENODEV; 948 } 949 950 if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) 951 return -ENODEV; 952 953 cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates); 954 955 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || 956 !(ecx & CPUID5_ECX_INTERRUPT_BREAK) || 957 !mwait_substates) 958 return -ENODEV; 959 960 pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates); 961 962 icpu = (const struct idle_cpu *)id->driver_data; 963 cpuidle_state_table = icpu->state_table; 964 965 if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ 966 lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; 967 else 968 on_each_cpu(__setup_broadcast_timer, (void *)true, 1); 969 970 pr_debug(PREFIX "v" INTEL_IDLE_VERSION 971 " model 0x%X\n", boot_cpu_data.x86_model); 972 973 pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n", 974 lapic_timer_reliable_states); 975 return 0; 976 } 977 978 /* 979 * intel_idle_cpuidle_devices_uninit() 980 * unregister, free cpuidle_devices 981 */ 982 static void intel_idle_cpuidle_devices_uninit(void) 983 { 984 int i; 985 struct cpuidle_device *dev; 986 987 for_each_online_cpu(i) { 988 dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); 989 cpuidle_unregister_device(dev); 990 } 991 992 free_percpu(intel_idle_cpuidle_devices); 993 return; 994 } 995 996 /* 997 * intel_idle_state_table_update() 998 * 999 * Update the default state_table for this CPU-id 1000 * 1001 * Currently used to access tuned IVT multi-socket targets 1002 * Assumption: num_sockets == (max_package_num + 1) 1003 */ 1004 void intel_idle_state_table_update(void) 1005 { 1006 /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */ 1007 if (boot_cpu_data.x86_model == 0x3e) { /* IVT */ 1008 int cpu, package_num, num_sockets = 1; 1009 1010 for_each_online_cpu(cpu) { 1011 package_num = topology_physical_package_id(cpu); 1012 if (package_num + 1 > num_sockets) { 1013 num_sockets = package_num + 1; 1014 1015 if (num_sockets > 4) { 1016 cpuidle_state_table = ivt_cstates_8s; 1017 return; 1018 } 1019 } 1020 } 1021 1022 if (num_sockets > 2) 1023 cpuidle_state_table = ivt_cstates_4s; 1024 /* else, 1 and 2 socket systems use default ivt_cstates */ 1025 } 1026 return; 1027 } 1028 1029 /* 1030 * intel_idle_cpuidle_driver_init() 1031 * allocate, initialize cpuidle_states 1032 */ 1033 static int __init intel_idle_cpuidle_driver_init(void) 1034 { 1035 int cstate; 1036 struct cpuidle_driver *drv = &intel_idle_driver; 1037 1038 intel_idle_state_table_update(); 1039 1040 drv->state_count = 1; 1041 1042 for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) { 1043 int num_substates, mwait_hint, mwait_cstate; 1044 1045 if ((cpuidle_state_table[cstate].enter == NULL) && 1046 (cpuidle_state_table[cstate].enter_freeze == NULL)) 1047 break; 1048 1049 if (cstate + 1 > max_cstate) { 1050 printk(PREFIX "max_cstate %d reached\n", 1051 max_cstate); 1052 break; 1053 } 1054 1055 mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); 1056 mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint); 1057 1058 /* number of sub-states for this state in CPUID.MWAIT */ 1059 num_substates = (mwait_substates >> ((mwait_cstate + 1) * 4)) 1060 & MWAIT_SUBSTATE_MASK; 1061 1062 /* if NO sub-states for this state in CPUID, skip it */ 1063 if (num_substates == 0) 1064 continue; 1065 1066 if (((mwait_cstate + 1) > 2) && 1067 !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 1068 mark_tsc_unstable("TSC halts in idle" 1069 " states deeper than C2"); 1070 1071 drv->states[drv->state_count] = /* structure copy */ 1072 cpuidle_state_table[cstate]; 1073 1074 drv->state_count += 1; 1075 } 1076 1077 if (icpu->auto_demotion_disable_flags) 1078 on_each_cpu(auto_demotion_disable, NULL, 1); 1079 1080 if (icpu->byt_auto_demotion_disable_flag) { 1081 wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0); 1082 wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0); 1083 } 1084 1085 if (icpu->disable_promotion_to_c1e) /* each-cpu is redundant */ 1086 on_each_cpu(c1e_promotion_disable, NULL, 1); 1087 1088 return 0; 1089 } 1090 1091 1092 /* 1093 * intel_idle_cpu_init() 1094 * allocate, initialize, register cpuidle_devices 1095 * @cpu: cpu/core to initialize 1096 */ 1097 static int intel_idle_cpu_init(int cpu) 1098 { 1099 struct cpuidle_device *dev; 1100 1101 dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu); 1102 1103 dev->cpu = cpu; 1104 1105 if (cpuidle_register_device(dev)) { 1106 pr_debug(PREFIX "cpuidle_register_device %d failed!\n", cpu); 1107 intel_idle_cpuidle_devices_uninit(); 1108 return -EIO; 1109 } 1110 1111 if (icpu->auto_demotion_disable_flags) 1112 smp_call_function_single(cpu, auto_demotion_disable, NULL, 1); 1113 1114 if (icpu->disable_promotion_to_c1e) 1115 smp_call_function_single(cpu, c1e_promotion_disable, NULL, 1); 1116 1117 return 0; 1118 } 1119 1120 static int __init intel_idle_init(void) 1121 { 1122 int retval, i; 1123 1124 /* Do not load intel_idle at all for now if idle= is passed */ 1125 if (boot_option_idle_override != IDLE_NO_OVERRIDE) 1126 return -ENODEV; 1127 1128 retval = intel_idle_probe(); 1129 if (retval) 1130 return retval; 1131 1132 intel_idle_cpuidle_driver_init(); 1133 retval = cpuidle_register_driver(&intel_idle_driver); 1134 if (retval) { 1135 struct cpuidle_driver *drv = cpuidle_get_driver(); 1136 printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", 1137 drv ? drv->name : "none"); 1138 return retval; 1139 } 1140 1141 intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); 1142 if (intel_idle_cpuidle_devices == NULL) 1143 return -ENOMEM; 1144 1145 cpu_notifier_register_begin(); 1146 1147 for_each_online_cpu(i) { 1148 retval = intel_idle_cpu_init(i); 1149 if (retval) { 1150 cpu_notifier_register_done(); 1151 cpuidle_unregister_driver(&intel_idle_driver); 1152 return retval; 1153 } 1154 } 1155 __register_cpu_notifier(&cpu_hotplug_notifier); 1156 1157 cpu_notifier_register_done(); 1158 1159 return 0; 1160 } 1161 1162 static void __exit intel_idle_exit(void) 1163 { 1164 intel_idle_cpuidle_devices_uninit(); 1165 cpuidle_unregister_driver(&intel_idle_driver); 1166 1167 cpu_notifier_register_begin(); 1168 1169 if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) 1170 on_each_cpu(__setup_broadcast_timer, (void *)false, 1); 1171 __unregister_cpu_notifier(&cpu_hotplug_notifier); 1172 1173 cpu_notifier_register_done(); 1174 1175 return; 1176 } 1177 1178 module_init(intel_idle_init); 1179 module_exit(intel_idle_exit); 1180 1181 module_param(max_cstate, int, 0444); 1182 1183 MODULE_AUTHOR("Len Brown <len.brown@intel.com>"); 1184 MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION); 1185 MODULE_LICENSE("GPL"); 1186