| 1 | /* |
| 2 | * processor_idle - idle state submodule to the ACPI processor driver |
| 3 | * |
| 4 | * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> |
| 5 | * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> |
| 6 | * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de> |
| 7 | * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> |
| 8 | * - Added processor hotplug support |
| 9 | * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> |
| 10 | * - Added support for C3 on SMP |
| 11 | * |
| 12 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 13 | * |
| 14 | * This program is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or (at |
| 17 | * your option) any later version. |
| 18 | * |
| 19 | * This program is distributed in the hope that it will be useful, but |
| 20 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 22 | * General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License along |
| 25 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 26 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. |
| 27 | * |
| 28 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 29 | */ |
| 30 | |
| 31 | #include <linux/kernel.h> |
| 32 | #include <linux/module.h> |
| 33 | #include <linux/init.h> |
| 34 | #include <linux/cpufreq.h> |
| 35 | #include <linux/proc_fs.h> |
| 36 | #include <linux/seq_file.h> |
| 37 | #include <linux/acpi.h> |
| 38 | #include <linux/dmi.h> |
| 39 | #include <linux/moduleparam.h> |
| 40 | #include <linux/sched.h> /* need_resched() */ |
| 41 | #include <linux/pm_qos_params.h> |
| 42 | #include <linux/clockchips.h> |
| 43 | #include <linux/cpuidle.h> |
| 44 | #include <linux/irqflags.h> |
| 45 | |
| 46 | /* |
| 47 | * Include the apic definitions for x86 to have the APIC timer related defines |
| 48 | * available also for UP (on SMP it gets magically included via linux/smp.h). |
| 49 | * asm/acpi.h is not an option, as it would require more include magic. Also |
| 50 | * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. |
| 51 | */ |
| 52 | #ifdef CONFIG_X86 |
| 53 | #include <asm/apic.h> |
| 54 | #endif |
| 55 | |
| 56 | #include <asm/io.h> |
| 57 | #include <asm/uaccess.h> |
| 58 | |
| 59 | #include <acpi/acpi_bus.h> |
| 60 | #include <acpi/processor.h> |
| 61 | #include <asm/processor.h> |
| 62 | |
| 63 | #define ACPI_PROCESSOR_CLASS "processor" |
| 64 | #define _COMPONENT ACPI_PROCESSOR_COMPONENT |
| 65 | ACPI_MODULE_NAME("processor_idle"); |
| 66 | #define ACPI_PROCESSOR_FILE_POWER "power" |
| 67 | #define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) |
| 68 | #define C2_OVERHEAD 1 /* 1us */ |
| 69 | #define C3_OVERHEAD 1 /* 1us */ |
| 70 | #define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000)) |
| 71 | |
| 72 | static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER; |
| 73 | module_param(max_cstate, uint, 0000); |
| 74 | static unsigned int nocst __read_mostly; |
| 75 | module_param(nocst, uint, 0000); |
| 76 | |
| 77 | static unsigned int latency_factor __read_mostly = 2; |
| 78 | module_param(latency_factor, uint, 0644); |
| 79 | |
| 80 | static s64 us_to_pm_timer_ticks(s64 t) |
| 81 | { |
| 82 | return div64_u64(t * PM_TIMER_FREQUENCY, 1000000); |
| 83 | } |
| 84 | /* |
| 85 | * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. |
| 86 | * For now disable this. Probably a bug somewhere else. |
| 87 | * |
| 88 | * To skip this limit, boot/load with a large max_cstate limit. |
| 89 | */ |
| 90 | static int set_max_cstate(const struct dmi_system_id *id) |
| 91 | { |
| 92 | if (max_cstate > ACPI_PROCESSOR_MAX_POWER) |
| 93 | return 0; |
| 94 | |
| 95 | printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." |
| 96 | " Override with \"processor.max_cstate=%d\"\n", id->ident, |
| 97 | (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); |
| 98 | |
| 99 | max_cstate = (long)id->driver_data; |
| 100 | |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | /* Actually this shouldn't be __cpuinitdata, would be better to fix the |
| 105 | callers to only run once -AK */ |
| 106 | static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { |
| 107 | { set_max_cstate, "Clevo 5600D", { |
| 108 | DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), |
| 109 | DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, |
| 110 | (void *)2}, |
| 111 | {}, |
| 112 | }; |
| 113 | |
| 114 | |
| 115 | /* |
| 116 | * Callers should disable interrupts before the call and enable |
| 117 | * interrupts after return. |
| 118 | */ |
| 119 | static void acpi_safe_halt(void) |
| 120 | { |
| 121 | current_thread_info()->status &= ~TS_POLLING; |
| 122 | /* |
| 123 | * TS_POLLING-cleared state must be visible before we |
| 124 | * test NEED_RESCHED: |
| 125 | */ |
| 126 | smp_mb(); |
| 127 | if (!need_resched()) { |
| 128 | safe_halt(); |
| 129 | local_irq_disable(); |
| 130 | } |
| 131 | current_thread_info()->status |= TS_POLLING; |
| 132 | } |
| 133 | |
| 134 | #ifdef ARCH_APICTIMER_STOPS_ON_C3 |
| 135 | |
| 136 | /* |
| 137 | * Some BIOS implementations switch to C3 in the published C2 state. |
| 138 | * This seems to be a common problem on AMD boxen, but other vendors |
| 139 | * are affected too. We pick the most conservative approach: we assume |
| 140 | * that the local APIC stops in both C2 and C3. |
| 141 | */ |
| 142 | static void acpi_timer_check_state(int state, struct acpi_processor *pr, |
| 143 | struct acpi_processor_cx *cx) |
| 144 | { |
| 145 | struct acpi_processor_power *pwr = &pr->power; |
| 146 | u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; |
| 147 | |
| 148 | if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT)) |
| 149 | return; |
| 150 | |
| 151 | if (boot_cpu_has(X86_FEATURE_AMDC1E)) |
| 152 | type = ACPI_STATE_C1; |
| 153 | |
| 154 | /* |
| 155 | * Check, if one of the previous states already marked the lapic |
| 156 | * unstable |
| 157 | */ |
| 158 | if (pwr->timer_broadcast_on_state < state) |
| 159 | return; |
| 160 | |
| 161 | if (cx->type >= type) |
| 162 | pr->power.timer_broadcast_on_state = state; |
| 163 | } |
| 164 | |
| 165 | static void acpi_propagate_timer_broadcast(struct acpi_processor *pr) |
| 166 | { |
| 167 | unsigned long reason; |
| 168 | |
| 169 | reason = pr->power.timer_broadcast_on_state < INT_MAX ? |
| 170 | CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; |
| 171 | |
| 172 | clockevents_notify(reason, &pr->id); |
| 173 | } |
| 174 | |
| 175 | /* Power(C) State timer broadcast control */ |
| 176 | static void acpi_state_timer_broadcast(struct acpi_processor *pr, |
| 177 | struct acpi_processor_cx *cx, |
| 178 | int broadcast) |
| 179 | { |
| 180 | int state = cx - pr->power.states; |
| 181 | |
| 182 | if (state >= pr->power.timer_broadcast_on_state) { |
| 183 | unsigned long reason; |
| 184 | |
| 185 | reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER : |
| 186 | CLOCK_EVT_NOTIFY_BROADCAST_EXIT; |
| 187 | clockevents_notify(reason, &pr->id); |
| 188 | } |
| 189 | } |
| 190 | |
| 191 | #else |
| 192 | |
| 193 | static void acpi_timer_check_state(int state, struct acpi_processor *pr, |
| 194 | struct acpi_processor_cx *cstate) { } |
| 195 | static void acpi_propagate_timer_broadcast(struct acpi_processor *pr) { } |
| 196 | static void acpi_state_timer_broadcast(struct acpi_processor *pr, |
| 197 | struct acpi_processor_cx *cx, |
| 198 | int broadcast) |
| 199 | { |
| 200 | } |
| 201 | |
| 202 | #endif |
| 203 | |
| 204 | /* |
| 205 | * Suspend / resume control |
| 206 | */ |
| 207 | static int acpi_idle_suspend; |
| 208 | static u32 saved_bm_rld; |
| 209 | |
| 210 | static void acpi_idle_bm_rld_save(void) |
| 211 | { |
| 212 | acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld); |
| 213 | } |
| 214 | static void acpi_idle_bm_rld_restore(void) |
| 215 | { |
| 216 | u32 resumed_bm_rld; |
| 217 | |
| 218 | acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld); |
| 219 | |
| 220 | if (resumed_bm_rld != saved_bm_rld) |
| 221 | acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld); |
| 222 | } |
| 223 | |
| 224 | int acpi_processor_suspend(struct acpi_device * device, pm_message_t state) |
| 225 | { |
| 226 | if (acpi_idle_suspend == 1) |
| 227 | return 0; |
| 228 | |
| 229 | acpi_idle_bm_rld_save(); |
| 230 | acpi_idle_suspend = 1; |
| 231 | return 0; |
| 232 | } |
| 233 | |
| 234 | int acpi_processor_resume(struct acpi_device * device) |
| 235 | { |
| 236 | if (acpi_idle_suspend == 0) |
| 237 | return 0; |
| 238 | |
| 239 | acpi_idle_bm_rld_restore(); |
| 240 | acpi_idle_suspend = 0; |
| 241 | return 0; |
| 242 | } |
| 243 | |
| 244 | #if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) |
| 245 | static void tsc_check_state(int state) |
| 246 | { |
| 247 | switch (boot_cpu_data.x86_vendor) { |
| 248 | case X86_VENDOR_AMD: |
| 249 | case X86_VENDOR_INTEL: |
| 250 | /* |
| 251 | * AMD Fam10h TSC will tick in all |
| 252 | * C/P/S0/S1 states when this bit is set. |
| 253 | */ |
| 254 | if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) |
| 255 | return; |
| 256 | |
| 257 | /*FALL THROUGH*/ |
| 258 | default: |
| 259 | /* TSC could halt in idle, so notify users */ |
| 260 | if (state > ACPI_STATE_C1) |
| 261 | mark_tsc_unstable("TSC halts in idle"); |
| 262 | } |
| 263 | } |
| 264 | #else |
| 265 | static void tsc_check_state(int state) { return; } |
| 266 | #endif |
| 267 | |
| 268 | static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) |
| 269 | { |
| 270 | |
| 271 | if (!pr) |
| 272 | return -EINVAL; |
| 273 | |
| 274 | if (!pr->pblk) |
| 275 | return -ENODEV; |
| 276 | |
| 277 | /* if info is obtained from pblk/fadt, type equals state */ |
| 278 | pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; |
| 279 | pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; |
| 280 | |
| 281 | #ifndef CONFIG_HOTPLUG_CPU |
| 282 | /* |
| 283 | * Check for P_LVL2_UP flag before entering C2 and above on |
| 284 | * an SMP system. |
| 285 | */ |
| 286 | if ((num_online_cpus() > 1) && |
| 287 | !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) |
| 288 | return -ENODEV; |
| 289 | #endif |
| 290 | |
| 291 | /* determine C2 and C3 address from pblk */ |
| 292 | pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; |
| 293 | pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; |
| 294 | |
| 295 | /* determine latencies from FADT */ |
| 296 | pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency; |
| 297 | pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency; |
| 298 | |
| 299 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 300 | "lvl2[0x%08x] lvl3[0x%08x]\n", |
| 301 | pr->power.states[ACPI_STATE_C2].address, |
| 302 | pr->power.states[ACPI_STATE_C3].address)); |
| 303 | |
| 304 | return 0; |
| 305 | } |
| 306 | |
| 307 | static int acpi_processor_get_power_info_default(struct acpi_processor *pr) |
| 308 | { |
| 309 | if (!pr->power.states[ACPI_STATE_C1].valid) { |
| 310 | /* set the first C-State to C1 */ |
| 311 | /* all processors need to support C1 */ |
| 312 | pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; |
| 313 | pr->power.states[ACPI_STATE_C1].valid = 1; |
| 314 | pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; |
| 315 | } |
| 316 | /* the C0 state only exists as a filler in our array */ |
| 317 | pr->power.states[ACPI_STATE_C0].valid = 1; |
| 318 | return 0; |
| 319 | } |
| 320 | |
| 321 | static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) |
| 322 | { |
| 323 | acpi_status status = 0; |
| 324 | acpi_integer count; |
| 325 | int current_count; |
| 326 | int i; |
| 327 | struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; |
| 328 | union acpi_object *cst; |
| 329 | |
| 330 | |
| 331 | if (nocst) |
| 332 | return -ENODEV; |
| 333 | |
| 334 | current_count = 0; |
| 335 | |
| 336 | status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); |
| 337 | if (ACPI_FAILURE(status)) { |
| 338 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); |
| 339 | return -ENODEV; |
| 340 | } |
| 341 | |
| 342 | cst = buffer.pointer; |
| 343 | |
| 344 | /* There must be at least 2 elements */ |
| 345 | if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { |
| 346 | printk(KERN_ERR PREFIX "not enough elements in _CST\n"); |
| 347 | status = -EFAULT; |
| 348 | goto end; |
| 349 | } |
| 350 | |
| 351 | count = cst->package.elements[0].integer.value; |
| 352 | |
| 353 | /* Validate number of power states. */ |
| 354 | if (count < 1 || count != cst->package.count - 1) { |
| 355 | printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); |
| 356 | status = -EFAULT; |
| 357 | goto end; |
| 358 | } |
| 359 | |
| 360 | /* Tell driver that at least _CST is supported. */ |
| 361 | pr->flags.has_cst = 1; |
| 362 | |
| 363 | for (i = 1; i <= count; i++) { |
| 364 | union acpi_object *element; |
| 365 | union acpi_object *obj; |
| 366 | struct acpi_power_register *reg; |
| 367 | struct acpi_processor_cx cx; |
| 368 | |
| 369 | memset(&cx, 0, sizeof(cx)); |
| 370 | |
| 371 | element = &(cst->package.elements[i]); |
| 372 | if (element->type != ACPI_TYPE_PACKAGE) |
| 373 | continue; |
| 374 | |
| 375 | if (element->package.count != 4) |
| 376 | continue; |
| 377 | |
| 378 | obj = &(element->package.elements[0]); |
| 379 | |
| 380 | if (obj->type != ACPI_TYPE_BUFFER) |
| 381 | continue; |
| 382 | |
| 383 | reg = (struct acpi_power_register *)obj->buffer.pointer; |
| 384 | |
| 385 | if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && |
| 386 | (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) |
| 387 | continue; |
| 388 | |
| 389 | /* There should be an easy way to extract an integer... */ |
| 390 | obj = &(element->package.elements[1]); |
| 391 | if (obj->type != ACPI_TYPE_INTEGER) |
| 392 | continue; |
| 393 | |
| 394 | cx.type = obj->integer.value; |
| 395 | /* |
| 396 | * Some buggy BIOSes won't list C1 in _CST - |
| 397 | * Let acpi_processor_get_power_info_default() handle them later |
| 398 | */ |
| 399 | if (i == 1 && cx.type != ACPI_STATE_C1) |
| 400 | current_count++; |
| 401 | |
| 402 | cx.address = reg->address; |
| 403 | cx.index = current_count + 1; |
| 404 | |
| 405 | cx.entry_method = ACPI_CSTATE_SYSTEMIO; |
| 406 | if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { |
| 407 | if (acpi_processor_ffh_cstate_probe |
| 408 | (pr->id, &cx, reg) == 0) { |
| 409 | cx.entry_method = ACPI_CSTATE_FFH; |
| 410 | } else if (cx.type == ACPI_STATE_C1) { |
| 411 | /* |
| 412 | * C1 is a special case where FIXED_HARDWARE |
| 413 | * can be handled in non-MWAIT way as well. |
| 414 | * In that case, save this _CST entry info. |
| 415 | * Otherwise, ignore this info and continue. |
| 416 | */ |
| 417 | cx.entry_method = ACPI_CSTATE_HALT; |
| 418 | snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); |
| 419 | } else { |
| 420 | continue; |
| 421 | } |
| 422 | if (cx.type == ACPI_STATE_C1 && |
| 423 | (idle_halt || idle_nomwait)) { |
| 424 | /* |
| 425 | * In most cases the C1 space_id obtained from |
| 426 | * _CST object is FIXED_HARDWARE access mode. |
| 427 | * But when the option of idle=halt is added, |
| 428 | * the entry_method type should be changed from |
| 429 | * CSTATE_FFH to CSTATE_HALT. |
| 430 | * When the option of idle=nomwait is added, |
| 431 | * the C1 entry_method type should be |
| 432 | * CSTATE_HALT. |
| 433 | */ |
| 434 | cx.entry_method = ACPI_CSTATE_HALT; |
| 435 | snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); |
| 436 | } |
| 437 | } else { |
| 438 | snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", |
| 439 | cx.address); |
| 440 | } |
| 441 | |
| 442 | if (cx.type == ACPI_STATE_C1) { |
| 443 | cx.valid = 1; |
| 444 | } |
| 445 | |
| 446 | obj = &(element->package.elements[2]); |
| 447 | if (obj->type != ACPI_TYPE_INTEGER) |
| 448 | continue; |
| 449 | |
| 450 | cx.latency = obj->integer.value; |
| 451 | |
| 452 | obj = &(element->package.elements[3]); |
| 453 | if (obj->type != ACPI_TYPE_INTEGER) |
| 454 | continue; |
| 455 | |
| 456 | cx.power = obj->integer.value; |
| 457 | |
| 458 | current_count++; |
| 459 | memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); |
| 460 | |
| 461 | /* |
| 462 | * We support total ACPI_PROCESSOR_MAX_POWER - 1 |
| 463 | * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) |
| 464 | */ |
| 465 | if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { |
| 466 | printk(KERN_WARNING |
| 467 | "Limiting number of power states to max (%d)\n", |
| 468 | ACPI_PROCESSOR_MAX_POWER); |
| 469 | printk(KERN_WARNING |
| 470 | "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); |
| 471 | break; |
| 472 | } |
| 473 | } |
| 474 | |
| 475 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", |
| 476 | current_count)); |
| 477 | |
| 478 | /* Validate number of power states discovered */ |
| 479 | if (current_count < 2) |
| 480 | status = -EFAULT; |
| 481 | |
| 482 | end: |
| 483 | kfree(buffer.pointer); |
| 484 | |
| 485 | return status; |
| 486 | } |
| 487 | |
| 488 | static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) |
| 489 | { |
| 490 | |
| 491 | if (!cx->address) |
| 492 | return; |
| 493 | |
| 494 | /* |
| 495 | * C2 latency must be less than or equal to 100 |
| 496 | * microseconds. |
| 497 | */ |
| 498 | else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { |
| 499 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 500 | "latency too large [%d]\n", cx->latency)); |
| 501 | return; |
| 502 | } |
| 503 | |
| 504 | /* |
| 505 | * Otherwise we've met all of our C2 requirements. |
| 506 | * Normalize the C2 latency to expidite policy |
| 507 | */ |
| 508 | cx->valid = 1; |
| 509 | |
| 510 | cx->latency_ticks = cx->latency; |
| 511 | |
| 512 | return; |
| 513 | } |
| 514 | |
| 515 | static void acpi_processor_power_verify_c3(struct acpi_processor *pr, |
| 516 | struct acpi_processor_cx *cx) |
| 517 | { |
| 518 | static int bm_check_flag; |
| 519 | |
| 520 | |
| 521 | if (!cx->address) |
| 522 | return; |
| 523 | |
| 524 | /* |
| 525 | * C3 latency must be less than or equal to 1000 |
| 526 | * microseconds. |
| 527 | */ |
| 528 | else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { |
| 529 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 530 | "latency too large [%d]\n", cx->latency)); |
| 531 | return; |
| 532 | } |
| 533 | |
| 534 | /* |
| 535 | * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) |
| 536 | * DMA transfers are used by any ISA device to avoid livelock. |
| 537 | * Note that we could disable Type-F DMA (as recommended by |
| 538 | * the erratum), but this is known to disrupt certain ISA |
| 539 | * devices thus we take the conservative approach. |
| 540 | */ |
| 541 | else if (errata.piix4.fdma) { |
| 542 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 543 | "C3 not supported on PIIX4 with Type-F DMA\n")); |
| 544 | return; |
| 545 | } |
| 546 | |
| 547 | /* All the logic here assumes flags.bm_check is same across all CPUs */ |
| 548 | if (!bm_check_flag) { |
| 549 | /* Determine whether bm_check is needed based on CPU */ |
| 550 | acpi_processor_power_init_bm_check(&(pr->flags), pr->id); |
| 551 | bm_check_flag = pr->flags.bm_check; |
| 552 | } else { |
| 553 | pr->flags.bm_check = bm_check_flag; |
| 554 | } |
| 555 | |
| 556 | if (pr->flags.bm_check) { |
| 557 | if (!pr->flags.bm_control) { |
| 558 | if (pr->flags.has_cst != 1) { |
| 559 | /* bus mastering control is necessary */ |
| 560 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 561 | "C3 support requires BM control\n")); |
| 562 | return; |
| 563 | } else { |
| 564 | /* Here we enter C3 without bus mastering */ |
| 565 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 566 | "C3 support without BM control\n")); |
| 567 | } |
| 568 | } |
| 569 | } else { |
| 570 | /* |
| 571 | * WBINVD should be set in fadt, for C3 state to be |
| 572 | * supported on when bm_check is not required. |
| 573 | */ |
| 574 | if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { |
| 575 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 576 | "Cache invalidation should work properly" |
| 577 | " for C3 to be enabled on SMP systems\n")); |
| 578 | return; |
| 579 | } |
| 580 | } |
| 581 | |
| 582 | /* |
| 583 | * Otherwise we've met all of our C3 requirements. |
| 584 | * Normalize the C3 latency to expidite policy. Enable |
| 585 | * checking of bus mastering status (bm_check) so we can |
| 586 | * use this in our C3 policy |
| 587 | */ |
| 588 | cx->valid = 1; |
| 589 | |
| 590 | cx->latency_ticks = cx->latency; |
| 591 | /* |
| 592 | * On older chipsets, BM_RLD needs to be set |
| 593 | * in order for Bus Master activity to wake the |
| 594 | * system from C3. Newer chipsets handle DMA |
| 595 | * during C3 automatically and BM_RLD is a NOP. |
| 596 | * In either case, the proper way to |
| 597 | * handle BM_RLD is to set it and leave it set. |
| 598 | */ |
| 599 | acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); |
| 600 | |
| 601 | return; |
| 602 | } |
| 603 | |
| 604 | static int acpi_processor_power_verify(struct acpi_processor *pr) |
| 605 | { |
| 606 | unsigned int i; |
| 607 | unsigned int working = 0; |
| 608 | |
| 609 | pr->power.timer_broadcast_on_state = INT_MAX; |
| 610 | |
| 611 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { |
| 612 | struct acpi_processor_cx *cx = &pr->power.states[i]; |
| 613 | |
| 614 | switch (cx->type) { |
| 615 | case ACPI_STATE_C1: |
| 616 | cx->valid = 1; |
| 617 | acpi_timer_check_state(i, pr, cx); |
| 618 | break; |
| 619 | |
| 620 | case ACPI_STATE_C2: |
| 621 | acpi_processor_power_verify_c2(cx); |
| 622 | if (cx->valid) |
| 623 | acpi_timer_check_state(i, pr, cx); |
| 624 | break; |
| 625 | |
| 626 | case ACPI_STATE_C3: |
| 627 | acpi_processor_power_verify_c3(pr, cx); |
| 628 | if (cx->valid) |
| 629 | acpi_timer_check_state(i, pr, cx); |
| 630 | break; |
| 631 | } |
| 632 | if (cx->valid) |
| 633 | tsc_check_state(cx->type); |
| 634 | |
| 635 | if (cx->valid) |
| 636 | working++; |
| 637 | } |
| 638 | |
| 639 | acpi_propagate_timer_broadcast(pr); |
| 640 | |
| 641 | return (working); |
| 642 | } |
| 643 | |
| 644 | static int acpi_processor_get_power_info(struct acpi_processor *pr) |
| 645 | { |
| 646 | unsigned int i; |
| 647 | int result; |
| 648 | |
| 649 | |
| 650 | /* NOTE: the idle thread may not be running while calling |
| 651 | * this function */ |
| 652 | |
| 653 | /* Zero initialize all the C-states info. */ |
| 654 | memset(pr->power.states, 0, sizeof(pr->power.states)); |
| 655 | |
| 656 | result = acpi_processor_get_power_info_cst(pr); |
| 657 | if (result == -ENODEV) |
| 658 | result = acpi_processor_get_power_info_fadt(pr); |
| 659 | |
| 660 | if (result) |
| 661 | return result; |
| 662 | |
| 663 | acpi_processor_get_power_info_default(pr); |
| 664 | |
| 665 | pr->power.count = acpi_processor_power_verify(pr); |
| 666 | |
| 667 | /* |
| 668 | * if one state of type C2 or C3 is available, mark this |
| 669 | * CPU as being "idle manageable" |
| 670 | */ |
| 671 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { |
| 672 | if (pr->power.states[i].valid) { |
| 673 | pr->power.count = i; |
| 674 | if (pr->power.states[i].type >= ACPI_STATE_C2) |
| 675 | pr->flags.power = 1; |
| 676 | } |
| 677 | } |
| 678 | |
| 679 | return 0; |
| 680 | } |
| 681 | |
| 682 | static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) |
| 683 | { |
| 684 | struct acpi_processor *pr = seq->private; |
| 685 | unsigned int i; |
| 686 | |
| 687 | |
| 688 | if (!pr) |
| 689 | goto end; |
| 690 | |
| 691 | seq_printf(seq, "active state: C%zd\n" |
| 692 | "max_cstate: C%d\n" |
| 693 | "maximum allowed latency: %d usec\n", |
| 694 | pr->power.state ? pr->power.state - pr->power.states : 0, |
| 695 | max_cstate, pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY)); |
| 696 | |
| 697 | seq_puts(seq, "states:\n"); |
| 698 | |
| 699 | for (i = 1; i <= pr->power.count; i++) { |
| 700 | seq_printf(seq, " %cC%d: ", |
| 701 | (&pr->power.states[i] == |
| 702 | pr->power.state ? '*' : ' '), i); |
| 703 | |
| 704 | if (!pr->power.states[i].valid) { |
| 705 | seq_puts(seq, "<not supported>\n"); |
| 706 | continue; |
| 707 | } |
| 708 | |
| 709 | switch (pr->power.states[i].type) { |
| 710 | case ACPI_STATE_C1: |
| 711 | seq_printf(seq, "type[C1] "); |
| 712 | break; |
| 713 | case ACPI_STATE_C2: |
| 714 | seq_printf(seq, "type[C2] "); |
| 715 | break; |
| 716 | case ACPI_STATE_C3: |
| 717 | seq_printf(seq, "type[C3] "); |
| 718 | break; |
| 719 | default: |
| 720 | seq_printf(seq, "type[--] "); |
| 721 | break; |
| 722 | } |
| 723 | |
| 724 | if (pr->power.states[i].promotion.state) |
| 725 | seq_printf(seq, "promotion[C%zd] ", |
| 726 | (pr->power.states[i].promotion.state - |
| 727 | pr->power.states)); |
| 728 | else |
| 729 | seq_puts(seq, "promotion[--] "); |
| 730 | |
| 731 | if (pr->power.states[i].demotion.state) |
| 732 | seq_printf(seq, "demotion[C%zd] ", |
| 733 | (pr->power.states[i].demotion.state - |
| 734 | pr->power.states)); |
| 735 | else |
| 736 | seq_puts(seq, "demotion[--] "); |
| 737 | |
| 738 | seq_printf(seq, "latency[%03d] usage[%08d] duration[%020llu]\n", |
| 739 | pr->power.states[i].latency, |
| 740 | pr->power.states[i].usage, |
| 741 | (unsigned long long)pr->power.states[i].time); |
| 742 | } |
| 743 | |
| 744 | end: |
| 745 | return 0; |
| 746 | } |
| 747 | |
| 748 | static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) |
| 749 | { |
| 750 | return single_open(file, acpi_processor_power_seq_show, |
| 751 | PDE(inode)->data); |
| 752 | } |
| 753 | |
| 754 | static const struct file_operations acpi_processor_power_fops = { |
| 755 | .owner = THIS_MODULE, |
| 756 | .open = acpi_processor_power_open_fs, |
| 757 | .read = seq_read, |
| 758 | .llseek = seq_lseek, |
| 759 | .release = single_release, |
| 760 | }; |
| 761 | |
| 762 | |
| 763 | /** |
| 764 | * acpi_idle_bm_check - checks if bus master activity was detected |
| 765 | */ |
| 766 | static int acpi_idle_bm_check(void) |
| 767 | { |
| 768 | u32 bm_status = 0; |
| 769 | |
| 770 | acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); |
| 771 | if (bm_status) |
| 772 | acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); |
| 773 | /* |
| 774 | * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect |
| 775 | * the true state of bus mastering activity; forcing us to |
| 776 | * manually check the BMIDEA bit of each IDE channel. |
| 777 | */ |
| 778 | else if (errata.piix4.bmisx) { |
| 779 | if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) |
| 780 | || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) |
| 781 | bm_status = 1; |
| 782 | } |
| 783 | return bm_status; |
| 784 | } |
| 785 | |
| 786 | /** |
| 787 | * acpi_idle_do_entry - a helper function that does C2 and C3 type entry |
| 788 | * @cx: cstate data |
| 789 | * |
| 790 | * Caller disables interrupt before call and enables interrupt after return. |
| 791 | */ |
| 792 | static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) |
| 793 | { |
| 794 | /* Don't trace irqs off for idle */ |
| 795 | stop_critical_timings(); |
| 796 | if (cx->entry_method == ACPI_CSTATE_FFH) { |
| 797 | /* Call into architectural FFH based C-state */ |
| 798 | acpi_processor_ffh_cstate_enter(cx); |
| 799 | } else if (cx->entry_method == ACPI_CSTATE_HALT) { |
| 800 | acpi_safe_halt(); |
| 801 | } else { |
| 802 | int unused; |
| 803 | /* IO port based C-state */ |
| 804 | inb(cx->address); |
| 805 | /* Dummy wait op - must do something useless after P_LVL2 read |
| 806 | because chipsets cannot guarantee that STPCLK# signal |
| 807 | gets asserted in time to freeze execution properly. */ |
| 808 | unused = inl(acpi_gbl_FADT.xpm_timer_block.address); |
| 809 | } |
| 810 | start_critical_timings(); |
| 811 | } |
| 812 | |
| 813 | /** |
| 814 | * acpi_idle_enter_c1 - enters an ACPI C1 state-type |
| 815 | * @dev: the target CPU |
| 816 | * @state: the state data |
| 817 | * |
| 818 | * This is equivalent to the HALT instruction. |
| 819 | */ |
| 820 | static int acpi_idle_enter_c1(struct cpuidle_device *dev, |
| 821 | struct cpuidle_state *state) |
| 822 | { |
| 823 | ktime_t kt1, kt2; |
| 824 | s64 idle_time; |
| 825 | struct acpi_processor *pr; |
| 826 | struct acpi_processor_cx *cx = cpuidle_get_statedata(state); |
| 827 | |
| 828 | pr = __get_cpu_var(processors); |
| 829 | |
| 830 | if (unlikely(!pr)) |
| 831 | return 0; |
| 832 | |
| 833 | local_irq_disable(); |
| 834 | |
| 835 | /* Do not access any ACPI IO ports in suspend path */ |
| 836 | if (acpi_idle_suspend) { |
| 837 | local_irq_enable(); |
| 838 | cpu_relax(); |
| 839 | return 0; |
| 840 | } |
| 841 | |
| 842 | acpi_state_timer_broadcast(pr, cx, 1); |
| 843 | kt1 = ktime_get_real(); |
| 844 | acpi_idle_do_entry(cx); |
| 845 | kt2 = ktime_get_real(); |
| 846 | idle_time = ktime_to_us(ktime_sub(kt2, kt1)); |
| 847 | |
| 848 | local_irq_enable(); |
| 849 | cx->usage++; |
| 850 | acpi_state_timer_broadcast(pr, cx, 0); |
| 851 | |
| 852 | return idle_time; |
| 853 | } |
| 854 | |
| 855 | /** |
| 856 | * acpi_idle_enter_simple - enters an ACPI state without BM handling |
| 857 | * @dev: the target CPU |
| 858 | * @state: the state data |
| 859 | */ |
| 860 | static int acpi_idle_enter_simple(struct cpuidle_device *dev, |
| 861 | struct cpuidle_state *state) |
| 862 | { |
| 863 | struct acpi_processor *pr; |
| 864 | struct acpi_processor_cx *cx = cpuidle_get_statedata(state); |
| 865 | ktime_t kt1, kt2; |
| 866 | s64 idle_time; |
| 867 | s64 sleep_ticks = 0; |
| 868 | |
| 869 | pr = __get_cpu_var(processors); |
| 870 | |
| 871 | if (unlikely(!pr)) |
| 872 | return 0; |
| 873 | |
| 874 | if (acpi_idle_suspend) |
| 875 | return(acpi_idle_enter_c1(dev, state)); |
| 876 | |
| 877 | local_irq_disable(); |
| 878 | current_thread_info()->status &= ~TS_POLLING; |
| 879 | /* |
| 880 | * TS_POLLING-cleared state must be visible before we test |
| 881 | * NEED_RESCHED: |
| 882 | */ |
| 883 | smp_mb(); |
| 884 | |
| 885 | if (unlikely(need_resched())) { |
| 886 | current_thread_info()->status |= TS_POLLING; |
| 887 | local_irq_enable(); |
| 888 | return 0; |
| 889 | } |
| 890 | |
| 891 | /* |
| 892 | * Must be done before busmaster disable as we might need to |
| 893 | * access HPET ! |
| 894 | */ |
| 895 | acpi_state_timer_broadcast(pr, cx, 1); |
| 896 | |
| 897 | if (cx->type == ACPI_STATE_C3) |
| 898 | ACPI_FLUSH_CPU_CACHE(); |
| 899 | |
| 900 | kt1 = ktime_get_real(); |
| 901 | /* Tell the scheduler that we are going deep-idle: */ |
| 902 | sched_clock_idle_sleep_event(); |
| 903 | acpi_idle_do_entry(cx); |
| 904 | kt2 = ktime_get_real(); |
| 905 | idle_time = ktime_to_us(ktime_sub(kt2, kt1)); |
| 906 | |
| 907 | sleep_ticks = us_to_pm_timer_ticks(idle_time); |
| 908 | |
| 909 | /* Tell the scheduler how much we idled: */ |
| 910 | sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); |
| 911 | |
| 912 | local_irq_enable(); |
| 913 | current_thread_info()->status |= TS_POLLING; |
| 914 | |
| 915 | cx->usage++; |
| 916 | |
| 917 | acpi_state_timer_broadcast(pr, cx, 0); |
| 918 | cx->time += sleep_ticks; |
| 919 | return idle_time; |
| 920 | } |
| 921 | |
| 922 | static int c3_cpu_count; |
| 923 | static DEFINE_SPINLOCK(c3_lock); |
| 924 | |
| 925 | /** |
| 926 | * acpi_idle_enter_bm - enters C3 with proper BM handling |
| 927 | * @dev: the target CPU |
| 928 | * @state: the state data |
| 929 | * |
| 930 | * If BM is detected, the deepest non-C3 idle state is entered instead. |
| 931 | */ |
| 932 | static int acpi_idle_enter_bm(struct cpuidle_device *dev, |
| 933 | struct cpuidle_state *state) |
| 934 | { |
| 935 | struct acpi_processor *pr; |
| 936 | struct acpi_processor_cx *cx = cpuidle_get_statedata(state); |
| 937 | ktime_t kt1, kt2; |
| 938 | s64 idle_time; |
| 939 | s64 sleep_ticks = 0; |
| 940 | |
| 941 | |
| 942 | pr = __get_cpu_var(processors); |
| 943 | |
| 944 | if (unlikely(!pr)) |
| 945 | return 0; |
| 946 | |
| 947 | if (acpi_idle_suspend) |
| 948 | return(acpi_idle_enter_c1(dev, state)); |
| 949 | |
| 950 | if (acpi_idle_bm_check()) { |
| 951 | if (dev->safe_state) { |
| 952 | dev->last_state = dev->safe_state; |
| 953 | return dev->safe_state->enter(dev, dev->safe_state); |
| 954 | } else { |
| 955 | local_irq_disable(); |
| 956 | acpi_safe_halt(); |
| 957 | local_irq_enable(); |
| 958 | return 0; |
| 959 | } |
| 960 | } |
| 961 | |
| 962 | local_irq_disable(); |
| 963 | current_thread_info()->status &= ~TS_POLLING; |
| 964 | /* |
| 965 | * TS_POLLING-cleared state must be visible before we test |
| 966 | * NEED_RESCHED: |
| 967 | */ |
| 968 | smp_mb(); |
| 969 | |
| 970 | if (unlikely(need_resched())) { |
| 971 | current_thread_info()->status |= TS_POLLING; |
| 972 | local_irq_enable(); |
| 973 | return 0; |
| 974 | } |
| 975 | |
| 976 | acpi_unlazy_tlb(smp_processor_id()); |
| 977 | |
| 978 | /* Tell the scheduler that we are going deep-idle: */ |
| 979 | sched_clock_idle_sleep_event(); |
| 980 | /* |
| 981 | * Must be done before busmaster disable as we might need to |
| 982 | * access HPET ! |
| 983 | */ |
| 984 | acpi_state_timer_broadcast(pr, cx, 1); |
| 985 | |
| 986 | kt1 = ktime_get_real(); |
| 987 | /* |
| 988 | * disable bus master |
| 989 | * bm_check implies we need ARB_DIS |
| 990 | * !bm_check implies we need cache flush |
| 991 | * bm_control implies whether we can do ARB_DIS |
| 992 | * |
| 993 | * That leaves a case where bm_check is set and bm_control is |
| 994 | * not set. In that case we cannot do much, we enter C3 |
| 995 | * without doing anything. |
| 996 | */ |
| 997 | if (pr->flags.bm_check && pr->flags.bm_control) { |
| 998 | spin_lock(&c3_lock); |
| 999 | c3_cpu_count++; |
| 1000 | /* Disable bus master arbitration when all CPUs are in C3 */ |
| 1001 | if (c3_cpu_count == num_online_cpus()) |
| 1002 | acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); |
| 1003 | spin_unlock(&c3_lock); |
| 1004 | } else if (!pr->flags.bm_check) { |
| 1005 | ACPI_FLUSH_CPU_CACHE(); |
| 1006 | } |
| 1007 | |
| 1008 | acpi_idle_do_entry(cx); |
| 1009 | |
| 1010 | /* Re-enable bus master arbitration */ |
| 1011 | if (pr->flags.bm_check && pr->flags.bm_control) { |
| 1012 | spin_lock(&c3_lock); |
| 1013 | acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); |
| 1014 | c3_cpu_count--; |
| 1015 | spin_unlock(&c3_lock); |
| 1016 | } |
| 1017 | kt2 = ktime_get_real(); |
| 1018 | idle_time = ktime_to_us(ktime_sub(kt2, kt1)); |
| 1019 | |
| 1020 | sleep_ticks = us_to_pm_timer_ticks(idle_time); |
| 1021 | /* Tell the scheduler how much we idled: */ |
| 1022 | sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); |
| 1023 | |
| 1024 | local_irq_enable(); |
| 1025 | current_thread_info()->status |= TS_POLLING; |
| 1026 | |
| 1027 | cx->usage++; |
| 1028 | |
| 1029 | acpi_state_timer_broadcast(pr, cx, 0); |
| 1030 | cx->time += sleep_ticks; |
| 1031 | return idle_time; |
| 1032 | } |
| 1033 | |
| 1034 | struct cpuidle_driver acpi_idle_driver = { |
| 1035 | .name = "acpi_idle", |
| 1036 | .owner = THIS_MODULE, |
| 1037 | }; |
| 1038 | |
| 1039 | /** |
| 1040 | * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE |
| 1041 | * @pr: the ACPI processor |
| 1042 | */ |
| 1043 | static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) |
| 1044 | { |
| 1045 | int i, count = CPUIDLE_DRIVER_STATE_START; |
| 1046 | struct acpi_processor_cx *cx; |
| 1047 | struct cpuidle_state *state; |
| 1048 | struct cpuidle_device *dev = &pr->power.dev; |
| 1049 | |
| 1050 | if (!pr->flags.power_setup_done) |
| 1051 | return -EINVAL; |
| 1052 | |
| 1053 | if (pr->flags.power == 0) { |
| 1054 | return -EINVAL; |
| 1055 | } |
| 1056 | |
| 1057 | dev->cpu = pr->id; |
| 1058 | for (i = 0; i < CPUIDLE_STATE_MAX; i++) { |
| 1059 | dev->states[i].name[0] = '\0'; |
| 1060 | dev->states[i].desc[0] = '\0'; |
| 1061 | } |
| 1062 | |
| 1063 | if (max_cstate == 0) |
| 1064 | max_cstate = 1; |
| 1065 | |
| 1066 | for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { |
| 1067 | cx = &pr->power.states[i]; |
| 1068 | state = &dev->states[count]; |
| 1069 | |
| 1070 | if (!cx->valid) |
| 1071 | continue; |
| 1072 | |
| 1073 | #ifdef CONFIG_HOTPLUG_CPU |
| 1074 | if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && |
| 1075 | !pr->flags.has_cst && |
| 1076 | !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) |
| 1077 | continue; |
| 1078 | #endif |
| 1079 | cpuidle_set_statedata(state, cx); |
| 1080 | |
| 1081 | snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); |
| 1082 | strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); |
| 1083 | state->exit_latency = cx->latency; |
| 1084 | state->target_residency = cx->latency * latency_factor; |
| 1085 | state->power_usage = cx->power; |
| 1086 | |
| 1087 | state->flags = 0; |
| 1088 | switch (cx->type) { |
| 1089 | case ACPI_STATE_C1: |
| 1090 | state->flags |= CPUIDLE_FLAG_SHALLOW; |
| 1091 | if (cx->entry_method == ACPI_CSTATE_FFH) |
| 1092 | state->flags |= CPUIDLE_FLAG_TIME_VALID; |
| 1093 | |
| 1094 | state->enter = acpi_idle_enter_c1; |
| 1095 | dev->safe_state = state; |
| 1096 | break; |
| 1097 | |
| 1098 | case ACPI_STATE_C2: |
| 1099 | state->flags |= CPUIDLE_FLAG_BALANCED; |
| 1100 | state->flags |= CPUIDLE_FLAG_TIME_VALID; |
| 1101 | state->enter = acpi_idle_enter_simple; |
| 1102 | dev->safe_state = state; |
| 1103 | break; |
| 1104 | |
| 1105 | case ACPI_STATE_C3: |
| 1106 | state->flags |= CPUIDLE_FLAG_DEEP; |
| 1107 | state->flags |= CPUIDLE_FLAG_TIME_VALID; |
| 1108 | state->flags |= CPUIDLE_FLAG_CHECK_BM; |
| 1109 | state->enter = pr->flags.bm_check ? |
| 1110 | acpi_idle_enter_bm : |
| 1111 | acpi_idle_enter_simple; |
| 1112 | break; |
| 1113 | } |
| 1114 | |
| 1115 | count++; |
| 1116 | if (count == CPUIDLE_STATE_MAX) |
| 1117 | break; |
| 1118 | } |
| 1119 | |
| 1120 | dev->state_count = count; |
| 1121 | |
| 1122 | if (!count) |
| 1123 | return -EINVAL; |
| 1124 | |
| 1125 | return 0; |
| 1126 | } |
| 1127 | |
| 1128 | int acpi_processor_cst_has_changed(struct acpi_processor *pr) |
| 1129 | { |
| 1130 | int ret = 0; |
| 1131 | |
| 1132 | if (boot_option_idle_override) |
| 1133 | return 0; |
| 1134 | |
| 1135 | if (!pr) |
| 1136 | return -EINVAL; |
| 1137 | |
| 1138 | if (nocst) { |
| 1139 | return -ENODEV; |
| 1140 | } |
| 1141 | |
| 1142 | if (!pr->flags.power_setup_done) |
| 1143 | return -ENODEV; |
| 1144 | |
| 1145 | cpuidle_pause_and_lock(); |
| 1146 | cpuidle_disable_device(&pr->power.dev); |
| 1147 | acpi_processor_get_power_info(pr); |
| 1148 | if (pr->flags.power) { |
| 1149 | acpi_processor_setup_cpuidle(pr); |
| 1150 | ret = cpuidle_enable_device(&pr->power.dev); |
| 1151 | } |
| 1152 | cpuidle_resume_and_unlock(); |
| 1153 | |
| 1154 | return ret; |
| 1155 | } |
| 1156 | |
| 1157 | int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, |
| 1158 | struct acpi_device *device) |
| 1159 | { |
| 1160 | acpi_status status = 0; |
| 1161 | static int first_run; |
| 1162 | struct proc_dir_entry *entry = NULL; |
| 1163 | unsigned int i; |
| 1164 | |
| 1165 | if (boot_option_idle_override) |
| 1166 | return 0; |
| 1167 | |
| 1168 | if (!first_run) { |
| 1169 | if (idle_halt) { |
| 1170 | /* |
| 1171 | * When the boot option of "idle=halt" is added, halt |
| 1172 | * is used for CPU IDLE. |
| 1173 | * In such case C2/C3 is meaningless. So the max_cstate |
| 1174 | * is set to one. |
| 1175 | */ |
| 1176 | max_cstate = 1; |
| 1177 | } |
| 1178 | dmi_check_system(processor_power_dmi_table); |
| 1179 | max_cstate = acpi_processor_cstate_check(max_cstate); |
| 1180 | if (max_cstate < ACPI_C_STATES_MAX) |
| 1181 | printk(KERN_NOTICE |
| 1182 | "ACPI: processor limited to max C-state %d\n", |
| 1183 | max_cstate); |
| 1184 | first_run++; |
| 1185 | } |
| 1186 | |
| 1187 | if (!pr) |
| 1188 | return -EINVAL; |
| 1189 | |
| 1190 | if (acpi_gbl_FADT.cst_control && !nocst) { |
| 1191 | status = |
| 1192 | acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8); |
| 1193 | if (ACPI_FAILURE(status)) { |
| 1194 | ACPI_EXCEPTION((AE_INFO, status, |
| 1195 | "Notifying BIOS of _CST ability failed")); |
| 1196 | } |
| 1197 | } |
| 1198 | |
| 1199 | acpi_processor_get_power_info(pr); |
| 1200 | pr->flags.power_setup_done = 1; |
| 1201 | |
| 1202 | /* |
| 1203 | * Install the idle handler if processor power management is supported. |
| 1204 | * Note that we use previously set idle handler will be used on |
| 1205 | * platforms that only support C1. |
| 1206 | */ |
| 1207 | if (pr->flags.power) { |
| 1208 | acpi_processor_setup_cpuidle(pr); |
| 1209 | if (cpuidle_register_device(&pr->power.dev)) |
| 1210 | return -EIO; |
| 1211 | |
| 1212 | printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); |
| 1213 | for (i = 1; i <= pr->power.count; i++) |
| 1214 | if (pr->power.states[i].valid) |
| 1215 | printk(" C%d[C%d]", i, |
| 1216 | pr->power.states[i].type); |
| 1217 | printk(")\n"); |
| 1218 | } |
| 1219 | |
| 1220 | /* 'power' [R] */ |
| 1221 | entry = proc_create_data(ACPI_PROCESSOR_FILE_POWER, |
| 1222 | S_IRUGO, acpi_device_dir(device), |
| 1223 | &acpi_processor_power_fops, |
| 1224 | acpi_driver_data(device)); |
| 1225 | if (!entry) |
| 1226 | return -EIO; |
| 1227 | return 0; |
| 1228 | } |
| 1229 | |
| 1230 | int acpi_processor_power_exit(struct acpi_processor *pr, |
| 1231 | struct acpi_device *device) |
| 1232 | { |
| 1233 | if (boot_option_idle_override) |
| 1234 | return 0; |
| 1235 | |
| 1236 | cpuidle_unregister_device(&pr->power.dev); |
| 1237 | pr->flags.power_setup_done = 0; |
| 1238 | |
| 1239 | if (acpi_device_dir(device)) |
| 1240 | remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, |
| 1241 | acpi_device_dir(device)); |
| 1242 | |
| 1243 | return 0; |
| 1244 | } |