11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * processor_idle - idle state submodule to the ACPI processor driver 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 51da177e4SLinus Torvalds * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6c5ab81caSDominik Brodowski * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de> 71da177e4SLinus Torvalds * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 81da177e4SLinus Torvalds * - Added processor hotplug support 902df8b93SVenkatesh Pallipadi * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> 1002df8b93SVenkatesh Pallipadi * - Added support for C3 on SMP 111da177e4SLinus Torvalds * 121da177e4SLinus Torvalds * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 131da177e4SLinus Torvalds * 141da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify 151da177e4SLinus Torvalds * it under the terms of the GNU General Public License as published by 161da177e4SLinus Torvalds * the Free Software Foundation; either version 2 of the License, or (at 171da177e4SLinus Torvalds * your option) any later version. 181da177e4SLinus Torvalds * 191da177e4SLinus Torvalds * This program is distributed in the hope that it will be useful, but 201da177e4SLinus Torvalds * WITHOUT ANY WARRANTY; without even the implied warranty of 211da177e4SLinus Torvalds * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 221da177e4SLinus Torvalds * General Public License for more details. 231da177e4SLinus Torvalds * 241da177e4SLinus Torvalds * You should have received a copy of the GNU General Public License along 251da177e4SLinus Torvalds * with this program; if not, write to the Free Software Foundation, Inc., 261da177e4SLinus Torvalds * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 271da177e4SLinus Torvalds * 281da177e4SLinus Torvalds * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 291da177e4SLinus Torvalds */ 301da177e4SLinus Torvalds 311da177e4SLinus Torvalds #include <linux/kernel.h> 321da177e4SLinus Torvalds #include <linux/module.h> 331da177e4SLinus Torvalds #include <linux/init.h> 341da177e4SLinus Torvalds #include <linux/cpufreq.h> 355a0e3ad6STejun Heo #include <linux/slab.h> 361da177e4SLinus Torvalds #include <linux/acpi.h> 371da177e4SLinus Torvalds #include <linux/dmi.h> 381da177e4SLinus Torvalds #include <linux/moduleparam.h> 394e57b681STim Schmielau #include <linux/sched.h> /* need_resched() */ 40f011e2e2SMark Gross #include <linux/pm_qos_params.h> 41e9e2cdb4SThomas Gleixner #include <linux/clockchips.h> 424f86d3a8SLen Brown #include <linux/cpuidle.h> 43ba84be23SRussell King #include <linux/irqflags.h> 441da177e4SLinus Torvalds 453434933bSThomas Gleixner /* 463434933bSThomas Gleixner * Include the apic definitions for x86 to have the APIC timer related defines 473434933bSThomas Gleixner * available also for UP (on SMP it gets magically included via linux/smp.h). 483434933bSThomas Gleixner * asm/acpi.h is not an option, as it would require more include magic. Also 493434933bSThomas Gleixner * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. 503434933bSThomas Gleixner */ 513434933bSThomas Gleixner #ifdef CONFIG_X86 523434933bSThomas Gleixner #include <asm/apic.h> 533434933bSThomas Gleixner #endif 543434933bSThomas Gleixner 551da177e4SLinus Torvalds #include <asm/io.h> 561da177e4SLinus Torvalds #include <asm/uaccess.h> 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #include <acpi/acpi_bus.h> 591da177e4SLinus Torvalds #include <acpi/processor.h> 60c1e3b377SZhao Yakui #include <asm/processor.h> 611da177e4SLinus Torvalds 62a192a958SLen Brown #define PREFIX "ACPI: " 63a192a958SLen Brown 641da177e4SLinus Torvalds #define ACPI_PROCESSOR_CLASS "processor" 651da177e4SLinus Torvalds #define _COMPONENT ACPI_PROCESSOR_COMPONENT 66f52fd66dSLen Brown ACPI_MODULE_NAME("processor_idle"); 672aa44d05SIngo Molnar #define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) 684f86d3a8SLen Brown #define C2_OVERHEAD 1 /* 1us */ 694f86d3a8SLen Brown #define C3_OVERHEAD 1 /* 1us */ 704f86d3a8SLen Brown #define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000)) 711da177e4SLinus Torvalds 724f86d3a8SLen Brown static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER; 734f86d3a8SLen Brown module_param(max_cstate, uint, 0000); 74b6835052SAndreas Mohr static unsigned int nocst __read_mostly; 751da177e4SLinus Torvalds module_param(nocst, uint, 0000); 76d3e7e99fSLen Brown static int bm_check_disable __read_mostly; 77d3e7e99fSLen Brown module_param(bm_check_disable, uint, 0000); 781da177e4SLinus Torvalds 7925de5718SLen Brown static unsigned int latency_factor __read_mostly = 2; 804963f620SLen Brown module_param(latency_factor, uint, 0644); 811da177e4SLinus Torvalds 821da177e4SLinus Torvalds /* 831da177e4SLinus Torvalds * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. 841da177e4SLinus Torvalds * For now disable this. Probably a bug somewhere else. 851da177e4SLinus Torvalds * 861da177e4SLinus Torvalds * To skip this limit, boot/load with a large max_cstate limit. 871da177e4SLinus Torvalds */ 881855256cSJeff Garzik static int set_max_cstate(const struct dmi_system_id *id) 891da177e4SLinus Torvalds { 901da177e4SLinus Torvalds if (max_cstate > ACPI_PROCESSOR_MAX_POWER) 911da177e4SLinus Torvalds return 0; 921da177e4SLinus Torvalds 933d35600aSLen Brown printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." 941da177e4SLinus Torvalds " Override with \"processor.max_cstate=%d\"\n", id->ident, 953d35600aSLen Brown (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); 961da177e4SLinus Torvalds 973d35600aSLen Brown max_cstate = (long)id->driver_data; 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds return 0; 1001da177e4SLinus Torvalds } 1011da177e4SLinus Torvalds 1027ded5689SAshok Raj /* Actually this shouldn't be __cpuinitdata, would be better to fix the 1037ded5689SAshok Raj callers to only run once -AK */ 1047ded5689SAshok Raj static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { 105335f16beSDavid Shaohua Li { set_max_cstate, "Clevo 5600D", { 106876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), 107876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, 108335f16beSDavid Shaohua Li (void *)2}, 109370d5cd8SArjan van de Ven { set_max_cstate, "Pavilion zv5000", { 110370d5cd8SArjan van de Ven DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 111370d5cd8SArjan van de Ven DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")}, 112370d5cd8SArjan van de Ven (void *)1}, 113370d5cd8SArjan van de Ven { set_max_cstate, "Asus L8400B", { 114370d5cd8SArjan van de Ven DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."), 115370d5cd8SArjan van de Ven DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")}, 116370d5cd8SArjan van de Ven (void *)1}, 1171da177e4SLinus Torvalds {}, 1181da177e4SLinus Torvalds }; 1191da177e4SLinus Torvalds 1204f86d3a8SLen Brown 1212e906655Svenkatesh.pallipadi@intel.com /* 1222e906655Svenkatesh.pallipadi@intel.com * Callers should disable interrupts before the call and enable 1232e906655Svenkatesh.pallipadi@intel.com * interrupts after return. 1242e906655Svenkatesh.pallipadi@intel.com */ 125ddc081a1SVenkatesh Pallipadi static void acpi_safe_halt(void) 126ddc081a1SVenkatesh Pallipadi { 127ddc081a1SVenkatesh Pallipadi current_thread_info()->status &= ~TS_POLLING; 128ddc081a1SVenkatesh Pallipadi /* 129ddc081a1SVenkatesh Pallipadi * TS_POLLING-cleared state must be visible before we 130ddc081a1SVenkatesh Pallipadi * test NEED_RESCHED: 131ddc081a1SVenkatesh Pallipadi */ 132ddc081a1SVenkatesh Pallipadi smp_mb(); 13371e93d15SVenki Pallipadi if (!need_resched()) { 134ddc081a1SVenkatesh Pallipadi safe_halt(); 13571e93d15SVenki Pallipadi local_irq_disable(); 13671e93d15SVenki Pallipadi } 137ddc081a1SVenkatesh Pallipadi current_thread_info()->status |= TS_POLLING; 138ddc081a1SVenkatesh Pallipadi } 139ddc081a1SVenkatesh Pallipadi 140169a0abbSThomas Gleixner #ifdef ARCH_APICTIMER_STOPS_ON_C3 141169a0abbSThomas Gleixner 142169a0abbSThomas Gleixner /* 143169a0abbSThomas Gleixner * Some BIOS implementations switch to C3 in the published C2 state. 144296d93cdSLinus Torvalds * This seems to be a common problem on AMD boxen, but other vendors 145296d93cdSLinus Torvalds * are affected too. We pick the most conservative approach: we assume 146296d93cdSLinus Torvalds * that the local APIC stops in both C2 and C3. 147169a0abbSThomas Gleixner */ 1487e275cc4SLen Brown static void lapic_timer_check_state(int state, struct acpi_processor *pr, 149169a0abbSThomas Gleixner struct acpi_processor_cx *cx) 150169a0abbSThomas Gleixner { 151169a0abbSThomas Gleixner struct acpi_processor_power *pwr = &pr->power; 152e585bef8SThomas Gleixner u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; 153169a0abbSThomas Gleixner 154db954b58SVenkatesh Pallipadi if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT)) 155db954b58SVenkatesh Pallipadi return; 156db954b58SVenkatesh Pallipadi 157e8c534ecSMichal Schmidt if (c1e_detected) 15887ad57baSShaohua Li type = ACPI_STATE_C1; 15987ad57baSShaohua Li 160169a0abbSThomas Gleixner /* 161169a0abbSThomas Gleixner * Check, if one of the previous states already marked the lapic 162169a0abbSThomas Gleixner * unstable 163169a0abbSThomas Gleixner */ 164169a0abbSThomas Gleixner if (pwr->timer_broadcast_on_state < state) 165169a0abbSThomas Gleixner return; 166169a0abbSThomas Gleixner 167e585bef8SThomas Gleixner if (cx->type >= type) 168169a0abbSThomas Gleixner pr->power.timer_broadcast_on_state = state; 169169a0abbSThomas Gleixner } 170169a0abbSThomas Gleixner 171918aae42SHidetoshi Seto static void __lapic_timer_propagate_broadcast(void *arg) 172169a0abbSThomas Gleixner { 173f833bab8SSuresh Siddha struct acpi_processor *pr = (struct acpi_processor *) arg; 174e9e2cdb4SThomas Gleixner unsigned long reason; 175e9e2cdb4SThomas Gleixner 176e9e2cdb4SThomas Gleixner reason = pr->power.timer_broadcast_on_state < INT_MAX ? 177e9e2cdb4SThomas Gleixner CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; 178e9e2cdb4SThomas Gleixner 179e9e2cdb4SThomas Gleixner clockevents_notify(reason, &pr->id); 180e9e2cdb4SThomas Gleixner } 181e9e2cdb4SThomas Gleixner 182918aae42SHidetoshi Seto static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) 183918aae42SHidetoshi Seto { 184918aae42SHidetoshi Seto smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast, 185918aae42SHidetoshi Seto (void *)pr, 1); 186918aae42SHidetoshi Seto } 187918aae42SHidetoshi Seto 188e9e2cdb4SThomas Gleixner /* Power(C) State timer broadcast control */ 1897e275cc4SLen Brown static void lapic_timer_state_broadcast(struct acpi_processor *pr, 190e9e2cdb4SThomas Gleixner struct acpi_processor_cx *cx, 191e9e2cdb4SThomas Gleixner int broadcast) 192e9e2cdb4SThomas Gleixner { 193e9e2cdb4SThomas Gleixner int state = cx - pr->power.states; 194e9e2cdb4SThomas Gleixner 195e9e2cdb4SThomas Gleixner if (state >= pr->power.timer_broadcast_on_state) { 196e9e2cdb4SThomas Gleixner unsigned long reason; 197e9e2cdb4SThomas Gleixner 198e9e2cdb4SThomas Gleixner reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER : 199e9e2cdb4SThomas Gleixner CLOCK_EVT_NOTIFY_BROADCAST_EXIT; 200e9e2cdb4SThomas Gleixner clockevents_notify(reason, &pr->id); 201e9e2cdb4SThomas Gleixner } 202169a0abbSThomas Gleixner } 203169a0abbSThomas Gleixner 204169a0abbSThomas Gleixner #else 205169a0abbSThomas Gleixner 2067e275cc4SLen Brown static void lapic_timer_check_state(int state, struct acpi_processor *pr, 207169a0abbSThomas Gleixner struct acpi_processor_cx *cstate) { } 2087e275cc4SLen Brown static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { } 2097e275cc4SLen Brown static void lapic_timer_state_broadcast(struct acpi_processor *pr, 210e9e2cdb4SThomas Gleixner struct acpi_processor_cx *cx, 211e9e2cdb4SThomas Gleixner int broadcast) 212e9e2cdb4SThomas Gleixner { 213e9e2cdb4SThomas Gleixner } 214169a0abbSThomas Gleixner 215169a0abbSThomas Gleixner #endif 216169a0abbSThomas Gleixner 217b04e7bdbSThomas Gleixner /* 218b04e7bdbSThomas Gleixner * Suspend / resume control 219b04e7bdbSThomas Gleixner */ 220b04e7bdbSThomas Gleixner static int acpi_idle_suspend; 221815ab0fdSLen Brown static u32 saved_bm_rld; 222815ab0fdSLen Brown 223815ab0fdSLen Brown static void acpi_idle_bm_rld_save(void) 224815ab0fdSLen Brown { 225815ab0fdSLen Brown acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld); 226815ab0fdSLen Brown } 227815ab0fdSLen Brown static void acpi_idle_bm_rld_restore(void) 228815ab0fdSLen Brown { 229815ab0fdSLen Brown u32 resumed_bm_rld; 230815ab0fdSLen Brown 231815ab0fdSLen Brown acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld); 232815ab0fdSLen Brown 233815ab0fdSLen Brown if (resumed_bm_rld != saved_bm_rld) 234815ab0fdSLen Brown acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld); 235815ab0fdSLen Brown } 236b04e7bdbSThomas Gleixner 237b04e7bdbSThomas Gleixner int acpi_processor_suspend(struct acpi_device * device, pm_message_t state) 238b04e7bdbSThomas Gleixner { 239815ab0fdSLen Brown if (acpi_idle_suspend == 1) 240815ab0fdSLen Brown return 0; 241815ab0fdSLen Brown 242815ab0fdSLen Brown acpi_idle_bm_rld_save(); 243b04e7bdbSThomas Gleixner acpi_idle_suspend = 1; 244b04e7bdbSThomas Gleixner return 0; 245b04e7bdbSThomas Gleixner } 246b04e7bdbSThomas Gleixner 247b04e7bdbSThomas Gleixner int acpi_processor_resume(struct acpi_device * device) 248b04e7bdbSThomas Gleixner { 249815ab0fdSLen Brown if (acpi_idle_suspend == 0) 250815ab0fdSLen Brown return 0; 251815ab0fdSLen Brown 252815ab0fdSLen Brown acpi_idle_bm_rld_restore(); 253b04e7bdbSThomas Gleixner acpi_idle_suspend = 0; 254b04e7bdbSThomas Gleixner return 0; 255b04e7bdbSThomas Gleixner } 256b04e7bdbSThomas Gleixner 257592913ecSJohn Stultz #if defined(CONFIG_X86) 258520daf72SLen Brown static void tsc_check_state(int state) 259ddb25f9aSAndi Kleen { 260ddb25f9aSAndi Kleen switch (boot_cpu_data.x86_vendor) { 261ddb25f9aSAndi Kleen case X86_VENDOR_AMD: 26240fb1715SVenki Pallipadi case X86_VENDOR_INTEL: 263ddb25f9aSAndi Kleen /* 264ddb25f9aSAndi Kleen * AMD Fam10h TSC will tick in all 265ddb25f9aSAndi Kleen * C/P/S0/S1 states when this bit is set. 266ddb25f9aSAndi Kleen */ 26740fb1715SVenki Pallipadi if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 268520daf72SLen Brown return; 26940fb1715SVenki Pallipadi 270ddb25f9aSAndi Kleen /*FALL THROUGH*/ 271ddb25f9aSAndi Kleen default: 272520daf72SLen Brown /* TSC could halt in idle, so notify users */ 273520daf72SLen Brown if (state > ACPI_STATE_C1) 274520daf72SLen Brown mark_tsc_unstable("TSC halts in idle"); 275ddb25f9aSAndi Kleen } 276ddb25f9aSAndi Kleen } 277520daf72SLen Brown #else 278520daf72SLen Brown static void tsc_check_state(int state) { return; } 279ddb25f9aSAndi Kleen #endif 280ddb25f9aSAndi Kleen 2811da177e4SLinus Torvalds static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 2821da177e4SLinus Torvalds { 2831da177e4SLinus Torvalds 2841da177e4SLinus Torvalds if (!pr) 285d550d98dSPatrick Mochel return -EINVAL; 2861da177e4SLinus Torvalds 2871da177e4SLinus Torvalds if (!pr->pblk) 288d550d98dSPatrick Mochel return -ENODEV; 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds /* if info is obtained from pblk/fadt, type equals state */ 2911da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; 2921da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; 2931da177e4SLinus Torvalds 2944c033552SVenkatesh Pallipadi #ifndef CONFIG_HOTPLUG_CPU 2954c033552SVenkatesh Pallipadi /* 2964c033552SVenkatesh Pallipadi * Check for P_LVL2_UP flag before entering C2 and above on 2974c033552SVenkatesh Pallipadi * an SMP system. 2984c033552SVenkatesh Pallipadi */ 299ad71860aSAlexey Starikovskiy if ((num_online_cpus() > 1) && 300cee324b1SAlexey Starikovskiy !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 301d550d98dSPatrick Mochel return -ENODEV; 3024c033552SVenkatesh Pallipadi #endif 3034c033552SVenkatesh Pallipadi 3041da177e4SLinus Torvalds /* determine C2 and C3 address from pblk */ 3051da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; 3061da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; 3071da177e4SLinus Torvalds 3081da177e4SLinus Torvalds /* determine latencies from FADT */ 309cee324b1SAlexey Starikovskiy pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency; 310cee324b1SAlexey Starikovskiy pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency; 3111da177e4SLinus Torvalds 3125d76b6f6SLen Brown /* 3135d76b6f6SLen Brown * FADT specified C2 latency must be less than or equal to 3145d76b6f6SLen Brown * 100 microseconds. 3155d76b6f6SLen Brown */ 3165d76b6f6SLen Brown if (acpi_gbl_FADT.C2latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { 3175d76b6f6SLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, 3185d76b6f6SLen Brown "C2 latency too large [%d]\n", acpi_gbl_FADT.C2latency)); 3195d76b6f6SLen Brown /* invalidate C2 */ 3205d76b6f6SLen Brown pr->power.states[ACPI_STATE_C2].address = 0; 3215d76b6f6SLen Brown } 3225d76b6f6SLen Brown 323a6d72c18SLen Brown /* 324a6d72c18SLen Brown * FADT supplied C3 latency must be less than or equal to 325a6d72c18SLen Brown * 1000 microseconds. 326a6d72c18SLen Brown */ 327a6d72c18SLen Brown if (acpi_gbl_FADT.C3latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { 328a6d72c18SLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, 329a6d72c18SLen Brown "C3 latency too large [%d]\n", acpi_gbl_FADT.C3latency)); 330a6d72c18SLen Brown /* invalidate C3 */ 331a6d72c18SLen Brown pr->power.states[ACPI_STATE_C3].address = 0; 332a6d72c18SLen Brown } 333a6d72c18SLen Brown 3341da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 3351da177e4SLinus Torvalds "lvl2[0x%08x] lvl3[0x%08x]\n", 3361da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address, 3371da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address)); 3381da177e4SLinus Torvalds 339d550d98dSPatrick Mochel return 0; 3401da177e4SLinus Torvalds } 3411da177e4SLinus Torvalds 342991528d7SVenkatesh Pallipadi static int acpi_processor_get_power_info_default(struct acpi_processor *pr) 343acf05f4bSVenkatesh Pallipadi { 344991528d7SVenkatesh Pallipadi if (!pr->power.states[ACPI_STATE_C1].valid) { 345cf824788SJanosch Machowinski /* set the first C-State to C1 */ 346991528d7SVenkatesh Pallipadi /* all processors need to support C1 */ 347acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; 348acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].valid = 1; 3490fda6b40SVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; 350991528d7SVenkatesh Pallipadi } 351991528d7SVenkatesh Pallipadi /* the C0 state only exists as a filler in our array */ 352991528d7SVenkatesh Pallipadi pr->power.states[ACPI_STATE_C0].valid = 1; 353d550d98dSPatrick Mochel return 0; 354acf05f4bSVenkatesh Pallipadi } 355acf05f4bSVenkatesh Pallipadi 3561da177e4SLinus Torvalds static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) 3571da177e4SLinus Torvalds { 3581da177e4SLinus Torvalds acpi_status status = 0; 359439913ffSLin Ming u64 count; 360cf824788SJanosch Machowinski int current_count; 3611da177e4SLinus Torvalds int i; 3621da177e4SLinus Torvalds struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 3631da177e4SLinus Torvalds union acpi_object *cst; 3641da177e4SLinus Torvalds 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds if (nocst) 367d550d98dSPatrick Mochel return -ENODEV; 3681da177e4SLinus Torvalds 369991528d7SVenkatesh Pallipadi current_count = 0; 3701da177e4SLinus Torvalds 3711da177e4SLinus Torvalds status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); 3721da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 3731da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); 374d550d98dSPatrick Mochel return -ENODEV; 3751da177e4SLinus Torvalds } 3761da177e4SLinus Torvalds 37750dd0969SJan Engelhardt cst = buffer.pointer; 3781da177e4SLinus Torvalds 3791da177e4SLinus Torvalds /* There must be at least 2 elements */ 3801da177e4SLinus Torvalds if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { 3816468463aSLen Brown printk(KERN_ERR PREFIX "not enough elements in _CST\n"); 3821da177e4SLinus Torvalds status = -EFAULT; 3831da177e4SLinus Torvalds goto end; 3841da177e4SLinus Torvalds } 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds count = cst->package.elements[0].integer.value; 3871da177e4SLinus Torvalds 3881da177e4SLinus Torvalds /* Validate number of power states. */ 3891da177e4SLinus Torvalds if (count < 1 || count != cst->package.count - 1) { 3906468463aSLen Brown printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); 3911da177e4SLinus Torvalds status = -EFAULT; 3921da177e4SLinus Torvalds goto end; 3931da177e4SLinus Torvalds } 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds /* Tell driver that at least _CST is supported. */ 3961da177e4SLinus Torvalds pr->flags.has_cst = 1; 3971da177e4SLinus Torvalds 3981da177e4SLinus Torvalds for (i = 1; i <= count; i++) { 3991da177e4SLinus Torvalds union acpi_object *element; 4001da177e4SLinus Torvalds union acpi_object *obj; 4011da177e4SLinus Torvalds struct acpi_power_register *reg; 4021da177e4SLinus Torvalds struct acpi_processor_cx cx; 4031da177e4SLinus Torvalds 4041da177e4SLinus Torvalds memset(&cx, 0, sizeof(cx)); 4051da177e4SLinus Torvalds 40650dd0969SJan Engelhardt element = &(cst->package.elements[i]); 4071da177e4SLinus Torvalds if (element->type != ACPI_TYPE_PACKAGE) 4081da177e4SLinus Torvalds continue; 4091da177e4SLinus Torvalds 4101da177e4SLinus Torvalds if (element->package.count != 4) 4111da177e4SLinus Torvalds continue; 4121da177e4SLinus Torvalds 41350dd0969SJan Engelhardt obj = &(element->package.elements[0]); 4141da177e4SLinus Torvalds 4151da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_BUFFER) 4161da177e4SLinus Torvalds continue; 4171da177e4SLinus Torvalds 4181da177e4SLinus Torvalds reg = (struct acpi_power_register *)obj->buffer.pointer; 4191da177e4SLinus Torvalds 4201da177e4SLinus Torvalds if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && 4211da177e4SLinus Torvalds (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) 4221da177e4SLinus Torvalds continue; 4231da177e4SLinus Torvalds 4241da177e4SLinus Torvalds /* There should be an easy way to extract an integer... */ 42550dd0969SJan Engelhardt obj = &(element->package.elements[1]); 4261da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4271da177e4SLinus Torvalds continue; 4281da177e4SLinus Torvalds 4291da177e4SLinus Torvalds cx.type = obj->integer.value; 430991528d7SVenkatesh Pallipadi /* 431991528d7SVenkatesh Pallipadi * Some buggy BIOSes won't list C1 in _CST - 432991528d7SVenkatesh Pallipadi * Let acpi_processor_get_power_info_default() handle them later 433991528d7SVenkatesh Pallipadi */ 434991528d7SVenkatesh Pallipadi if (i == 1 && cx.type != ACPI_STATE_C1) 435991528d7SVenkatesh Pallipadi current_count++; 4361da177e4SLinus Torvalds 437991528d7SVenkatesh Pallipadi cx.address = reg->address; 438991528d7SVenkatesh Pallipadi cx.index = current_count + 1; 4391da177e4SLinus Torvalds 440bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_SYSTEMIO; 441991528d7SVenkatesh Pallipadi if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { 442991528d7SVenkatesh Pallipadi if (acpi_processor_ffh_cstate_probe 443991528d7SVenkatesh Pallipadi (pr->id, &cx, reg) == 0) { 444bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_FFH; 445bc71bec9Svenkatesh.pallipadi@intel.com } else if (cx.type == ACPI_STATE_C1) { 446991528d7SVenkatesh Pallipadi /* 447991528d7SVenkatesh Pallipadi * C1 is a special case where FIXED_HARDWARE 448991528d7SVenkatesh Pallipadi * can be handled in non-MWAIT way as well. 449991528d7SVenkatesh Pallipadi * In that case, save this _CST entry info. 450991528d7SVenkatesh Pallipadi * Otherwise, ignore this info and continue. 451991528d7SVenkatesh Pallipadi */ 452bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_HALT; 4534fcb2fcdSVenkatesh Pallipadi snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); 454bc71bec9Svenkatesh.pallipadi@intel.com } else { 4551da177e4SLinus Torvalds continue; 456991528d7SVenkatesh Pallipadi } 457da5e09a1SZhao Yakui if (cx.type == ACPI_STATE_C1 && 458da5e09a1SZhao Yakui (idle_halt || idle_nomwait)) { 459c1e3b377SZhao Yakui /* 460c1e3b377SZhao Yakui * In most cases the C1 space_id obtained from 461c1e3b377SZhao Yakui * _CST object is FIXED_HARDWARE access mode. 462c1e3b377SZhao Yakui * But when the option of idle=halt is added, 463c1e3b377SZhao Yakui * the entry_method type should be changed from 464c1e3b377SZhao Yakui * CSTATE_FFH to CSTATE_HALT. 465da5e09a1SZhao Yakui * When the option of idle=nomwait is added, 466da5e09a1SZhao Yakui * the C1 entry_method type should be 467da5e09a1SZhao Yakui * CSTATE_HALT. 468c1e3b377SZhao Yakui */ 469c1e3b377SZhao Yakui cx.entry_method = ACPI_CSTATE_HALT; 470c1e3b377SZhao Yakui snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); 471c1e3b377SZhao Yakui } 4724fcb2fcdSVenkatesh Pallipadi } else { 4734fcb2fcdSVenkatesh Pallipadi snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", 4744fcb2fcdSVenkatesh Pallipadi cx.address); 475991528d7SVenkatesh Pallipadi } 4761da177e4SLinus Torvalds 4770fda6b40SVenkatesh Pallipadi if (cx.type == ACPI_STATE_C1) { 4780fda6b40SVenkatesh Pallipadi cx.valid = 1; 4790fda6b40SVenkatesh Pallipadi } 4804fcb2fcdSVenkatesh Pallipadi 48150dd0969SJan Engelhardt obj = &(element->package.elements[2]); 4821da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4831da177e4SLinus Torvalds continue; 4841da177e4SLinus Torvalds 4851da177e4SLinus Torvalds cx.latency = obj->integer.value; 4861da177e4SLinus Torvalds 48750dd0969SJan Engelhardt obj = &(element->package.elements[3]); 4881da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4891da177e4SLinus Torvalds continue; 4901da177e4SLinus Torvalds 4911da177e4SLinus Torvalds cx.power = obj->integer.value; 4921da177e4SLinus Torvalds 493cf824788SJanosch Machowinski current_count++; 494cf824788SJanosch Machowinski memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); 495cf824788SJanosch Machowinski 496cf824788SJanosch Machowinski /* 497cf824788SJanosch Machowinski * We support total ACPI_PROCESSOR_MAX_POWER - 1 498cf824788SJanosch Machowinski * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) 499cf824788SJanosch Machowinski */ 500cf824788SJanosch Machowinski if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { 501cf824788SJanosch Machowinski printk(KERN_WARNING 502cf824788SJanosch Machowinski "Limiting number of power states to max (%d)\n", 503cf824788SJanosch Machowinski ACPI_PROCESSOR_MAX_POWER); 504cf824788SJanosch Machowinski printk(KERN_WARNING 505cf824788SJanosch Machowinski "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); 506cf824788SJanosch Machowinski break; 507cf824788SJanosch Machowinski } 5081da177e4SLinus Torvalds } 5091da177e4SLinus Torvalds 5104be44fcdSLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", 511cf824788SJanosch Machowinski current_count)); 5121da177e4SLinus Torvalds 5131da177e4SLinus Torvalds /* Validate number of power states discovered */ 514cf824788SJanosch Machowinski if (current_count < 2) 5156d93c648SVenkatesh Pallipadi status = -EFAULT; 5161da177e4SLinus Torvalds 5171da177e4SLinus Torvalds end: 51802438d87SLen Brown kfree(buffer.pointer); 5191da177e4SLinus Torvalds 520d550d98dSPatrick Mochel return status; 5211da177e4SLinus Torvalds } 5221da177e4SLinus Torvalds 5234be44fcdSLen Brown static void acpi_processor_power_verify_c3(struct acpi_processor *pr, 5241da177e4SLinus Torvalds struct acpi_processor_cx *cx) 5251da177e4SLinus Torvalds { 526ee1ca48fSPallipadi, Venkatesh static int bm_check_flag = -1; 527ee1ca48fSPallipadi, Venkatesh static int bm_control_flag = -1; 52802df8b93SVenkatesh Pallipadi 5291da177e4SLinus Torvalds 5301da177e4SLinus Torvalds if (!cx->address) 531d550d98dSPatrick Mochel return; 5321da177e4SLinus Torvalds 5331da177e4SLinus Torvalds /* 5341da177e4SLinus Torvalds * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) 5351da177e4SLinus Torvalds * DMA transfers are used by any ISA device to avoid livelock. 5361da177e4SLinus Torvalds * Note that we could disable Type-F DMA (as recommended by 5371da177e4SLinus Torvalds * the erratum), but this is known to disrupt certain ISA 5381da177e4SLinus Torvalds * devices thus we take the conservative approach. 5391da177e4SLinus Torvalds */ 5401da177e4SLinus Torvalds else if (errata.piix4.fdma) { 5411da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 5421da177e4SLinus Torvalds "C3 not supported on PIIX4 with Type-F DMA\n")); 543d550d98dSPatrick Mochel return; 5441da177e4SLinus Torvalds } 5451da177e4SLinus Torvalds 54602df8b93SVenkatesh Pallipadi /* All the logic here assumes flags.bm_check is same across all CPUs */ 547ee1ca48fSPallipadi, Venkatesh if (bm_check_flag == -1) { 54802df8b93SVenkatesh Pallipadi /* Determine whether bm_check is needed based on CPU */ 54902df8b93SVenkatesh Pallipadi acpi_processor_power_init_bm_check(&(pr->flags), pr->id); 55002df8b93SVenkatesh Pallipadi bm_check_flag = pr->flags.bm_check; 551ee1ca48fSPallipadi, Venkatesh bm_control_flag = pr->flags.bm_control; 55202df8b93SVenkatesh Pallipadi } else { 55302df8b93SVenkatesh Pallipadi pr->flags.bm_check = bm_check_flag; 554ee1ca48fSPallipadi, Venkatesh pr->flags.bm_control = bm_control_flag; 55502df8b93SVenkatesh Pallipadi } 55602df8b93SVenkatesh Pallipadi 55702df8b93SVenkatesh Pallipadi if (pr->flags.bm_check) { 55802df8b93SVenkatesh Pallipadi if (!pr->flags.bm_control) { 559ed3110efSVenki Pallipadi if (pr->flags.has_cst != 1) { 560ed3110efSVenki Pallipadi /* bus mastering control is necessary */ 56102df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 562ed3110efSVenki Pallipadi "C3 support requires BM control\n")); 563ed3110efSVenki Pallipadi return; 564ed3110efSVenki Pallipadi } else { 565ed3110efSVenki Pallipadi /* Here we enter C3 without bus mastering */ 566ed3110efSVenki Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 567ed3110efSVenki Pallipadi "C3 support without BM control\n")); 568ed3110efSVenki Pallipadi } 56902df8b93SVenkatesh Pallipadi } 57002df8b93SVenkatesh Pallipadi } else { 57102df8b93SVenkatesh Pallipadi /* 57202df8b93SVenkatesh Pallipadi * WBINVD should be set in fadt, for C3 state to be 57302df8b93SVenkatesh Pallipadi * supported on when bm_check is not required. 57402df8b93SVenkatesh Pallipadi */ 575cee324b1SAlexey Starikovskiy if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { 57602df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 57702df8b93SVenkatesh Pallipadi "Cache invalidation should work properly" 57802df8b93SVenkatesh Pallipadi " for C3 to be enabled on SMP systems\n")); 579d550d98dSPatrick Mochel return; 58002df8b93SVenkatesh Pallipadi } 58102df8b93SVenkatesh Pallipadi } 58202df8b93SVenkatesh Pallipadi 5831da177e4SLinus Torvalds /* 5841da177e4SLinus Torvalds * Otherwise we've met all of our C3 requirements. 5851da177e4SLinus Torvalds * Normalize the C3 latency to expidite policy. Enable 5861da177e4SLinus Torvalds * checking of bus mastering status (bm_check) so we can 5871da177e4SLinus Torvalds * use this in our C3 policy 5881da177e4SLinus Torvalds */ 5891da177e4SLinus Torvalds cx->valid = 1; 5904f86d3a8SLen Brown 5914f86d3a8SLen Brown cx->latency_ticks = cx->latency; 59231878dd8SLen Brown /* 59331878dd8SLen Brown * On older chipsets, BM_RLD needs to be set 59431878dd8SLen Brown * in order for Bus Master activity to wake the 59531878dd8SLen Brown * system from C3. Newer chipsets handle DMA 59631878dd8SLen Brown * during C3 automatically and BM_RLD is a NOP. 59731878dd8SLen Brown * In either case, the proper way to 59831878dd8SLen Brown * handle BM_RLD is to set it and leave it set. 59931878dd8SLen Brown */ 60050ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); 6011da177e4SLinus Torvalds 602d550d98dSPatrick Mochel return; 6031da177e4SLinus Torvalds } 6041da177e4SLinus Torvalds 6051da177e4SLinus Torvalds static int acpi_processor_power_verify(struct acpi_processor *pr) 6061da177e4SLinus Torvalds { 6071da177e4SLinus Torvalds unsigned int i; 6081da177e4SLinus Torvalds unsigned int working = 0; 6096eb0a0fdSVenkatesh Pallipadi 610169a0abbSThomas Gleixner pr->power.timer_broadcast_on_state = INT_MAX; 6116eb0a0fdSVenkatesh Pallipadi 612a0bf284bSLen Brown for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 6131da177e4SLinus Torvalds struct acpi_processor_cx *cx = &pr->power.states[i]; 6141da177e4SLinus Torvalds 6151da177e4SLinus Torvalds switch (cx->type) { 6161da177e4SLinus Torvalds case ACPI_STATE_C1: 6171da177e4SLinus Torvalds cx->valid = 1; 6181da177e4SLinus Torvalds break; 6191da177e4SLinus Torvalds 6201da177e4SLinus Torvalds case ACPI_STATE_C2: 621d22edd29SLen Brown if (!cx->address) 622d22edd29SLen Brown break; 623d22edd29SLen Brown cx->valid = 1; 624d22edd29SLen Brown cx->latency_ticks = cx->latency; /* Normalize latency */ 6251da177e4SLinus Torvalds break; 6261da177e4SLinus Torvalds 6271da177e4SLinus Torvalds case ACPI_STATE_C3: 6281da177e4SLinus Torvalds acpi_processor_power_verify_c3(pr, cx); 6291da177e4SLinus Torvalds break; 6301da177e4SLinus Torvalds } 6317e275cc4SLen Brown if (!cx->valid) 6327e275cc4SLen Brown continue; 6331da177e4SLinus Torvalds 6347e275cc4SLen Brown lapic_timer_check_state(i, pr, cx); 6357e275cc4SLen Brown tsc_check_state(cx->type); 6361da177e4SLinus Torvalds working++; 6371da177e4SLinus Torvalds } 6381da177e4SLinus Torvalds 639918aae42SHidetoshi Seto lapic_timer_propagate_broadcast(pr); 640bd663347SAndi Kleen 6411da177e4SLinus Torvalds return (working); 6421da177e4SLinus Torvalds } 6431da177e4SLinus Torvalds 6444be44fcdSLen Brown static int acpi_processor_get_power_info(struct acpi_processor *pr) 6451da177e4SLinus Torvalds { 6461da177e4SLinus Torvalds unsigned int i; 6471da177e4SLinus Torvalds int result; 6481da177e4SLinus Torvalds 6491da177e4SLinus Torvalds 6501da177e4SLinus Torvalds /* NOTE: the idle thread may not be running while calling 6511da177e4SLinus Torvalds * this function */ 6521da177e4SLinus Torvalds 653991528d7SVenkatesh Pallipadi /* Zero initialize all the C-states info. */ 654991528d7SVenkatesh Pallipadi memset(pr->power.states, 0, sizeof(pr->power.states)); 655991528d7SVenkatesh Pallipadi 6561da177e4SLinus Torvalds result = acpi_processor_get_power_info_cst(pr); 6576d93c648SVenkatesh Pallipadi if (result == -ENODEV) 658c5a114f1SDarrick J. Wong result = acpi_processor_get_power_info_fadt(pr); 6596d93c648SVenkatesh Pallipadi 660991528d7SVenkatesh Pallipadi if (result) 661991528d7SVenkatesh Pallipadi return result; 662991528d7SVenkatesh Pallipadi 663991528d7SVenkatesh Pallipadi acpi_processor_get_power_info_default(pr); 664991528d7SVenkatesh Pallipadi 665cf824788SJanosch Machowinski pr->power.count = acpi_processor_power_verify(pr); 6661da177e4SLinus Torvalds 6671da177e4SLinus Torvalds /* 6681da177e4SLinus Torvalds * if one state of type C2 or C3 is available, mark this 6691da177e4SLinus Torvalds * CPU as being "idle manageable" 6701da177e4SLinus Torvalds */ 6711da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 672acf05f4bSVenkatesh Pallipadi if (pr->power.states[i].valid) { 6731da177e4SLinus Torvalds pr->power.count = i; 6742203d6edSLinus Torvalds if (pr->power.states[i].type >= ACPI_STATE_C2) 6751da177e4SLinus Torvalds pr->flags.power = 1; 6761da177e4SLinus Torvalds } 677acf05f4bSVenkatesh Pallipadi } 6781da177e4SLinus Torvalds 679d550d98dSPatrick Mochel return 0; 6801da177e4SLinus Torvalds } 6811da177e4SLinus Torvalds 6824f86d3a8SLen Brown /** 6834f86d3a8SLen Brown * acpi_idle_bm_check - checks if bus master activity was detected 6844f86d3a8SLen Brown */ 6854f86d3a8SLen Brown static int acpi_idle_bm_check(void) 6864f86d3a8SLen Brown { 6874f86d3a8SLen Brown u32 bm_status = 0; 6884f86d3a8SLen Brown 689d3e7e99fSLen Brown if (bm_check_disable) 690d3e7e99fSLen Brown return 0; 691d3e7e99fSLen Brown 69250ffba1bSBob Moore acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); 6934f86d3a8SLen Brown if (bm_status) 69450ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); 6954f86d3a8SLen Brown /* 6964f86d3a8SLen Brown * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect 6974f86d3a8SLen Brown * the true state of bus mastering activity; forcing us to 6984f86d3a8SLen Brown * manually check the BMIDEA bit of each IDE channel. 6994f86d3a8SLen Brown */ 7004f86d3a8SLen Brown else if (errata.piix4.bmisx) { 7014f86d3a8SLen Brown if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) 7024f86d3a8SLen Brown || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) 7034f86d3a8SLen Brown bm_status = 1; 7044f86d3a8SLen Brown } 7054f86d3a8SLen Brown return bm_status; 7064f86d3a8SLen Brown } 7074f86d3a8SLen Brown 7084f86d3a8SLen Brown /** 7094f86d3a8SLen Brown * acpi_idle_do_entry - a helper function that does C2 and C3 type entry 7104f86d3a8SLen Brown * @cx: cstate data 711bc71bec9Svenkatesh.pallipadi@intel.com * 712bc71bec9Svenkatesh.pallipadi@intel.com * Caller disables interrupt before call and enables interrupt after return. 7134f86d3a8SLen Brown */ 7144f86d3a8SLen Brown static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) 7154f86d3a8SLen Brown { 716dcf30997SSteven Rostedt /* Don't trace irqs off for idle */ 717dcf30997SSteven Rostedt stop_critical_timings(); 718bc71bec9Svenkatesh.pallipadi@intel.com if (cx->entry_method == ACPI_CSTATE_FFH) { 7194f86d3a8SLen Brown /* Call into architectural FFH based C-state */ 7204f86d3a8SLen Brown acpi_processor_ffh_cstate_enter(cx); 721bc71bec9Svenkatesh.pallipadi@intel.com } else if (cx->entry_method == ACPI_CSTATE_HALT) { 722bc71bec9Svenkatesh.pallipadi@intel.com acpi_safe_halt(); 7234f86d3a8SLen Brown } else { 7244f86d3a8SLen Brown /* IO port based C-state */ 7254f86d3a8SLen Brown inb(cx->address); 7264f86d3a8SLen Brown /* Dummy wait op - must do something useless after P_LVL2 read 7274f86d3a8SLen Brown because chipsets cannot guarantee that STPCLK# signal 7284f86d3a8SLen Brown gets asserted in time to freeze execution properly. */ 729cfa806f0SAndi Kleen inl(acpi_gbl_FADT.xpm_timer_block.address); 7304f86d3a8SLen Brown } 731dcf30997SSteven Rostedt start_critical_timings(); 7324f86d3a8SLen Brown } 7334f86d3a8SLen Brown 7344f86d3a8SLen Brown /** 7354f86d3a8SLen Brown * acpi_idle_enter_c1 - enters an ACPI C1 state-type 7364f86d3a8SLen Brown * @dev: the target CPU 7374f86d3a8SLen Brown * @state: the state data 7384f86d3a8SLen Brown * 7394f86d3a8SLen Brown * This is equivalent to the HALT instruction. 7404f86d3a8SLen Brown */ 7414f86d3a8SLen Brown static int acpi_idle_enter_c1(struct cpuidle_device *dev, 7424f86d3a8SLen Brown struct cpuidle_state *state) 7434f86d3a8SLen Brown { 744ff69f2bbSalex.shi ktime_t kt1, kt2; 745ff69f2bbSalex.shi s64 idle_time; 7464f86d3a8SLen Brown struct acpi_processor *pr; 7474f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 7489b12e18cSvenkatesh.pallipadi@intel.com 7494a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 7504f86d3a8SLen Brown 7514f86d3a8SLen Brown if (unlikely(!pr)) 7524f86d3a8SLen Brown return 0; 7534f86d3a8SLen Brown 7542e906655Svenkatesh.pallipadi@intel.com local_irq_disable(); 755b077fbadSVenkatesh Pallipadi 756b077fbadSVenkatesh Pallipadi /* Do not access any ACPI IO ports in suspend path */ 757b077fbadSVenkatesh Pallipadi if (acpi_idle_suspend) { 758b077fbadSVenkatesh Pallipadi local_irq_enable(); 7597d60e8abSShaohua Li cpu_relax(); 760b077fbadSVenkatesh Pallipadi return 0; 761b077fbadSVenkatesh Pallipadi } 762b077fbadSVenkatesh Pallipadi 7637e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 764ff69f2bbSalex.shi kt1 = ktime_get_real(); 765bc71bec9Svenkatesh.pallipadi@intel.com acpi_idle_do_entry(cx); 766ff69f2bbSalex.shi kt2 = ktime_get_real(); 767ff69f2bbSalex.shi idle_time = ktime_to_us(ktime_sub(kt2, kt1)); 7684f86d3a8SLen Brown 7692e906655Svenkatesh.pallipadi@intel.com local_irq_enable(); 7704f86d3a8SLen Brown cx->usage++; 7717e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 7724f86d3a8SLen Brown 773ff69f2bbSalex.shi return idle_time; 7744f86d3a8SLen Brown } 7754f86d3a8SLen Brown 7764f86d3a8SLen Brown /** 7774f86d3a8SLen Brown * acpi_idle_enter_simple - enters an ACPI state without BM handling 7784f86d3a8SLen Brown * @dev: the target CPU 7794f86d3a8SLen Brown * @state: the state data 7804f86d3a8SLen Brown */ 7814f86d3a8SLen Brown static int acpi_idle_enter_simple(struct cpuidle_device *dev, 7824f86d3a8SLen Brown struct cpuidle_state *state) 7834f86d3a8SLen Brown { 7844f86d3a8SLen Brown struct acpi_processor *pr; 7854f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 786ff69f2bbSalex.shi ktime_t kt1, kt2; 7872da513f5SVenkatesh Pallipadi s64 idle_time_ns; 788ff69f2bbSalex.shi s64 idle_time; 78950629118SVenkatesh Pallipadi 7904a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 7914f86d3a8SLen Brown 7924f86d3a8SLen Brown if (unlikely(!pr)) 7934f86d3a8SLen Brown return 0; 7944f86d3a8SLen Brown 795e196441bSLen Brown if (acpi_idle_suspend) 796e196441bSLen Brown return(acpi_idle_enter_c1(dev, state)); 797e196441bSLen Brown 7984f86d3a8SLen Brown local_irq_disable(); 79902cf4f98SLen Brown 800d306ebc2SPallipadi, Venkatesh if (cx->entry_method != ACPI_CSTATE_FFH) { 8014f86d3a8SLen Brown current_thread_info()->status &= ~TS_POLLING; 8024f86d3a8SLen Brown /* 8034f86d3a8SLen Brown * TS_POLLING-cleared state must be visible before we test 8044f86d3a8SLen Brown * NEED_RESCHED: 8054f86d3a8SLen Brown */ 8064f86d3a8SLen Brown smp_mb(); 8074f86d3a8SLen Brown 8084f86d3a8SLen Brown if (unlikely(need_resched())) { 8094f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 8104f86d3a8SLen Brown local_irq_enable(); 8114f86d3a8SLen Brown return 0; 8124f86d3a8SLen Brown } 81302cf4f98SLen Brown } 8144f86d3a8SLen Brown 815e17bcb43SThomas Gleixner /* 816e17bcb43SThomas Gleixner * Must be done before busmaster disable as we might need to 817e17bcb43SThomas Gleixner * access HPET ! 818e17bcb43SThomas Gleixner */ 8197e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 820e17bcb43SThomas Gleixner 8214f86d3a8SLen Brown if (cx->type == ACPI_STATE_C3) 8224f86d3a8SLen Brown ACPI_FLUSH_CPU_CACHE(); 8234f86d3a8SLen Brown 824ff69f2bbSalex.shi kt1 = ktime_get_real(); 82550629118SVenkatesh Pallipadi /* Tell the scheduler that we are going deep-idle: */ 82650629118SVenkatesh Pallipadi sched_clock_idle_sleep_event(); 8274f86d3a8SLen Brown acpi_idle_do_entry(cx); 828ff69f2bbSalex.shi kt2 = ktime_get_real(); 8292da513f5SVenkatesh Pallipadi idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1)); 8302da513f5SVenkatesh Pallipadi idle_time = idle_time_ns; 8312da513f5SVenkatesh Pallipadi do_div(idle_time, NSEC_PER_USEC); 8324f86d3a8SLen Brown 83350629118SVenkatesh Pallipadi /* Tell the scheduler how much we idled: */ 8342da513f5SVenkatesh Pallipadi sched_clock_idle_wakeup_event(idle_time_ns); 8354f86d3a8SLen Brown 8364f86d3a8SLen Brown local_irq_enable(); 83702cf4f98SLen Brown if (cx->entry_method != ACPI_CSTATE_FFH) 8384f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 8394f86d3a8SLen Brown 8404f86d3a8SLen Brown cx->usage++; 8414f86d3a8SLen Brown 8427e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 843bceefad5SVenkatesh Pallipadi cx->time += idle_time; 844ff69f2bbSalex.shi return idle_time; 8454f86d3a8SLen Brown } 8464f86d3a8SLen Brown 8474f86d3a8SLen Brown static int c3_cpu_count; 8484f86d3a8SLen Brown static DEFINE_SPINLOCK(c3_lock); 8494f86d3a8SLen Brown 8504f86d3a8SLen Brown /** 8514f86d3a8SLen Brown * acpi_idle_enter_bm - enters C3 with proper BM handling 8524f86d3a8SLen Brown * @dev: the target CPU 8534f86d3a8SLen Brown * @state: the state data 8544f86d3a8SLen Brown * 8554f86d3a8SLen Brown * If BM is detected, the deepest non-C3 idle state is entered instead. 8564f86d3a8SLen Brown */ 8574f86d3a8SLen Brown static int acpi_idle_enter_bm(struct cpuidle_device *dev, 8584f86d3a8SLen Brown struct cpuidle_state *state) 8594f86d3a8SLen Brown { 8604f86d3a8SLen Brown struct acpi_processor *pr; 8614f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 862ff69f2bbSalex.shi ktime_t kt1, kt2; 8632da513f5SVenkatesh Pallipadi s64 idle_time_ns; 864ff69f2bbSalex.shi s64 idle_time; 865ff69f2bbSalex.shi 86650629118SVenkatesh Pallipadi 8674a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 8684f86d3a8SLen Brown 8694f86d3a8SLen Brown if (unlikely(!pr)) 8704f86d3a8SLen Brown return 0; 8714f86d3a8SLen Brown 872e196441bSLen Brown if (acpi_idle_suspend) 873e196441bSLen Brown return(acpi_idle_enter_c1(dev, state)); 874e196441bSLen Brown 875718be4aaSLen Brown if (!cx->bm_sts_skip && acpi_idle_bm_check()) { 876ddc081a1SVenkatesh Pallipadi if (dev->safe_state) { 877addbad46SVenkatesh Pallipadi dev->last_state = dev->safe_state; 878ddc081a1SVenkatesh Pallipadi return dev->safe_state->enter(dev, dev->safe_state); 879ddc081a1SVenkatesh Pallipadi } else { 8802e906655Svenkatesh.pallipadi@intel.com local_irq_disable(); 881ddc081a1SVenkatesh Pallipadi acpi_safe_halt(); 8822e906655Svenkatesh.pallipadi@intel.com local_irq_enable(); 883ddc081a1SVenkatesh Pallipadi return 0; 884ddc081a1SVenkatesh Pallipadi } 885ddc081a1SVenkatesh Pallipadi } 886ddc081a1SVenkatesh Pallipadi 8874f86d3a8SLen Brown local_irq_disable(); 88802cf4f98SLen Brown 889d306ebc2SPallipadi, Venkatesh if (cx->entry_method != ACPI_CSTATE_FFH) { 8904f86d3a8SLen Brown current_thread_info()->status &= ~TS_POLLING; 8914f86d3a8SLen Brown /* 8924f86d3a8SLen Brown * TS_POLLING-cleared state must be visible before we test 8934f86d3a8SLen Brown * NEED_RESCHED: 8944f86d3a8SLen Brown */ 8954f86d3a8SLen Brown smp_mb(); 8964f86d3a8SLen Brown 8974f86d3a8SLen Brown if (unlikely(need_resched())) { 8984f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 8994f86d3a8SLen Brown local_irq_enable(); 9004f86d3a8SLen Brown return 0; 9014f86d3a8SLen Brown } 90202cf4f98SLen Brown } 9034f86d3a8SLen Brown 904996520c1SVenki Pallipadi acpi_unlazy_tlb(smp_processor_id()); 905996520c1SVenki Pallipadi 90650629118SVenkatesh Pallipadi /* Tell the scheduler that we are going deep-idle: */ 90750629118SVenkatesh Pallipadi sched_clock_idle_sleep_event(); 9084f86d3a8SLen Brown /* 9094f86d3a8SLen Brown * Must be done before busmaster disable as we might need to 9104f86d3a8SLen Brown * access HPET ! 9114f86d3a8SLen Brown */ 9127e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 9134f86d3a8SLen Brown 914f461ddeaSLen Brown kt1 = ktime_get_real(); 915c9c860e5SVenkatesh Pallipadi /* 916c9c860e5SVenkatesh Pallipadi * disable bus master 917c9c860e5SVenkatesh Pallipadi * bm_check implies we need ARB_DIS 918c9c860e5SVenkatesh Pallipadi * !bm_check implies we need cache flush 919c9c860e5SVenkatesh Pallipadi * bm_control implies whether we can do ARB_DIS 920c9c860e5SVenkatesh Pallipadi * 921c9c860e5SVenkatesh Pallipadi * That leaves a case where bm_check is set and bm_control is 922c9c860e5SVenkatesh Pallipadi * not set. In that case we cannot do much, we enter C3 923c9c860e5SVenkatesh Pallipadi * without doing anything. 924c9c860e5SVenkatesh Pallipadi */ 925c9c860e5SVenkatesh Pallipadi if (pr->flags.bm_check && pr->flags.bm_control) { 9264f86d3a8SLen Brown spin_lock(&c3_lock); 9274f86d3a8SLen Brown c3_cpu_count++; 9284f86d3a8SLen Brown /* Disable bus master arbitration when all CPUs are in C3 */ 9294f86d3a8SLen Brown if (c3_cpu_count == num_online_cpus()) 93050ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); 9314f86d3a8SLen Brown spin_unlock(&c3_lock); 932c9c860e5SVenkatesh Pallipadi } else if (!pr->flags.bm_check) { 933c9c860e5SVenkatesh Pallipadi ACPI_FLUSH_CPU_CACHE(); 934c9c860e5SVenkatesh Pallipadi } 9354f86d3a8SLen Brown 9364f86d3a8SLen Brown acpi_idle_do_entry(cx); 9374f86d3a8SLen Brown 9384f86d3a8SLen Brown /* Re-enable bus master arbitration */ 939c9c860e5SVenkatesh Pallipadi if (pr->flags.bm_check && pr->flags.bm_control) { 940c9c860e5SVenkatesh Pallipadi spin_lock(&c3_lock); 94150ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); 9424f86d3a8SLen Brown c3_cpu_count--; 9434f86d3a8SLen Brown spin_unlock(&c3_lock); 9444f86d3a8SLen Brown } 945f461ddeaSLen Brown kt2 = ktime_get_real(); 946157317baSZhao Yakui idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1)); 9472da513f5SVenkatesh Pallipadi idle_time = idle_time_ns; 9482da513f5SVenkatesh Pallipadi do_div(idle_time, NSEC_PER_USEC); 9494f86d3a8SLen Brown 95050629118SVenkatesh Pallipadi /* Tell the scheduler how much we idled: */ 9512da513f5SVenkatesh Pallipadi sched_clock_idle_wakeup_event(idle_time_ns); 9524f86d3a8SLen Brown 9534f86d3a8SLen Brown local_irq_enable(); 95402cf4f98SLen Brown if (cx->entry_method != ACPI_CSTATE_FFH) 9554f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 9564f86d3a8SLen Brown 9574f86d3a8SLen Brown cx->usage++; 9584f86d3a8SLen Brown 9597e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 960bceefad5SVenkatesh Pallipadi cx->time += idle_time; 961ff69f2bbSalex.shi return idle_time; 9624f86d3a8SLen Brown } 9634f86d3a8SLen Brown 9644f86d3a8SLen Brown struct cpuidle_driver acpi_idle_driver = { 9654f86d3a8SLen Brown .name = "acpi_idle", 9664f86d3a8SLen Brown .owner = THIS_MODULE, 9674f86d3a8SLen Brown }; 9684f86d3a8SLen Brown 9694f86d3a8SLen Brown /** 9704f86d3a8SLen Brown * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE 9714f86d3a8SLen Brown * @pr: the ACPI processor 9724f86d3a8SLen Brown */ 9734f86d3a8SLen Brown static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) 9744f86d3a8SLen Brown { 9759a0b8415Svenkatesh.pallipadi@intel.com int i, count = CPUIDLE_DRIVER_STATE_START; 9764f86d3a8SLen Brown struct acpi_processor_cx *cx; 9774f86d3a8SLen Brown struct cpuidle_state *state; 9784f86d3a8SLen Brown struct cpuidle_device *dev = &pr->power.dev; 9794f86d3a8SLen Brown 9804f86d3a8SLen Brown if (!pr->flags.power_setup_done) 9814f86d3a8SLen Brown return -EINVAL; 9824f86d3a8SLen Brown 9834f86d3a8SLen Brown if (pr->flags.power == 0) { 9844f86d3a8SLen Brown return -EINVAL; 9854f86d3a8SLen Brown } 9864f86d3a8SLen Brown 987dcb84f33SVenkatesh Pallipadi dev->cpu = pr->id; 9884fcb2fcdSVenkatesh Pallipadi for (i = 0; i < CPUIDLE_STATE_MAX; i++) { 9894fcb2fcdSVenkatesh Pallipadi dev->states[i].name[0] = '\0'; 9904fcb2fcdSVenkatesh Pallipadi dev->states[i].desc[0] = '\0'; 9914fcb2fcdSVenkatesh Pallipadi } 9924fcb2fcdSVenkatesh Pallipadi 993615dfd93SLen Brown if (max_cstate == 0) 994615dfd93SLen Brown max_cstate = 1; 995615dfd93SLen Brown 9964f86d3a8SLen Brown for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 9974f86d3a8SLen Brown cx = &pr->power.states[i]; 9984f86d3a8SLen Brown state = &dev->states[count]; 9994f86d3a8SLen Brown 10004f86d3a8SLen Brown if (!cx->valid) 10014f86d3a8SLen Brown continue; 10024f86d3a8SLen Brown 10034f86d3a8SLen Brown #ifdef CONFIG_HOTPLUG_CPU 10044f86d3a8SLen Brown if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && 10054f86d3a8SLen Brown !pr->flags.has_cst && 10064f86d3a8SLen Brown !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 10074f86d3a8SLen Brown continue; 10084f86d3a8SLen Brown #endif 10094f86d3a8SLen Brown cpuidle_set_statedata(state, cx); 10104f86d3a8SLen Brown 10114f86d3a8SLen Brown snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); 10124fcb2fcdSVenkatesh Pallipadi strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); 10134f86d3a8SLen Brown state->exit_latency = cx->latency; 10144963f620SLen Brown state->target_residency = cx->latency * latency_factor; 10154f86d3a8SLen Brown 10164f86d3a8SLen Brown state->flags = 0; 10174f86d3a8SLen Brown switch (cx->type) { 10184f86d3a8SLen Brown case ACPI_STATE_C1: 10194f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_SHALLOW; 10208e92b660SVenki Pallipadi if (cx->entry_method == ACPI_CSTATE_FFH) 10219b12e18cSvenkatesh.pallipadi@intel.com state->flags |= CPUIDLE_FLAG_TIME_VALID; 10228e92b660SVenki Pallipadi 10234f86d3a8SLen Brown state->enter = acpi_idle_enter_c1; 1024ddc081a1SVenkatesh Pallipadi dev->safe_state = state; 10254f86d3a8SLen Brown break; 10264f86d3a8SLen Brown 10274f86d3a8SLen Brown case ACPI_STATE_C2: 10284f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_BALANCED; 10294f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_TIME_VALID; 10304f86d3a8SLen Brown state->enter = acpi_idle_enter_simple; 1031ddc081a1SVenkatesh Pallipadi dev->safe_state = state; 10324f86d3a8SLen Brown break; 10334f86d3a8SLen Brown 10344f86d3a8SLen Brown case ACPI_STATE_C3: 10354f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_DEEP; 10364f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_TIME_VALID; 10374f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_CHECK_BM; 10384f86d3a8SLen Brown state->enter = pr->flags.bm_check ? 10394f86d3a8SLen Brown acpi_idle_enter_bm : 10404f86d3a8SLen Brown acpi_idle_enter_simple; 10414f86d3a8SLen Brown break; 10424f86d3a8SLen Brown } 10434f86d3a8SLen Brown 10444f86d3a8SLen Brown count++; 10459a0b8415Svenkatesh.pallipadi@intel.com if (count == CPUIDLE_STATE_MAX) 10469a0b8415Svenkatesh.pallipadi@intel.com break; 10474f86d3a8SLen Brown } 10484f86d3a8SLen Brown 10494f86d3a8SLen Brown dev->state_count = count; 10504f86d3a8SLen Brown 10514f86d3a8SLen Brown if (!count) 10524f86d3a8SLen Brown return -EINVAL; 10534f86d3a8SLen Brown 10544f86d3a8SLen Brown return 0; 10554f86d3a8SLen Brown } 10564f86d3a8SLen Brown 10574f86d3a8SLen Brown int acpi_processor_cst_has_changed(struct acpi_processor *pr) 10584f86d3a8SLen Brown { 1059dcb84f33SVenkatesh Pallipadi int ret = 0; 10604f86d3a8SLen Brown 106136a91358SVenkatesh Pallipadi if (boot_option_idle_override) 106236a91358SVenkatesh Pallipadi return 0; 106336a91358SVenkatesh Pallipadi 10644f86d3a8SLen Brown if (!pr) 10654f86d3a8SLen Brown return -EINVAL; 10664f86d3a8SLen Brown 10674f86d3a8SLen Brown if (nocst) { 10684f86d3a8SLen Brown return -ENODEV; 10694f86d3a8SLen Brown } 10704f86d3a8SLen Brown 10714f86d3a8SLen Brown if (!pr->flags.power_setup_done) 10724f86d3a8SLen Brown return -ENODEV; 10734f86d3a8SLen Brown 10744f86d3a8SLen Brown cpuidle_pause_and_lock(); 10754f86d3a8SLen Brown cpuidle_disable_device(&pr->power.dev); 10764f86d3a8SLen Brown acpi_processor_get_power_info(pr); 1077dcb84f33SVenkatesh Pallipadi if (pr->flags.power) { 10784f86d3a8SLen Brown acpi_processor_setup_cpuidle(pr); 10794f86d3a8SLen Brown ret = cpuidle_enable_device(&pr->power.dev); 1080dcb84f33SVenkatesh Pallipadi } 10814f86d3a8SLen Brown cpuidle_resume_and_unlock(); 10824f86d3a8SLen Brown 10834f86d3a8SLen Brown return ret; 10844f86d3a8SLen Brown } 10854f86d3a8SLen Brown 10867af8b660SPierre Ossman int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, 10874be44fcdSLen Brown struct acpi_device *device) 10881da177e4SLinus Torvalds { 10891da177e4SLinus Torvalds acpi_status status = 0; 1090b6835052SAndreas Mohr static int first_run; 10911da177e4SLinus Torvalds 109236a91358SVenkatesh Pallipadi if (boot_option_idle_override) 109336a91358SVenkatesh Pallipadi return 0; 10941da177e4SLinus Torvalds 10951da177e4SLinus Torvalds if (!first_run) { 1096c1e3b377SZhao Yakui if (idle_halt) { 1097c1e3b377SZhao Yakui /* 1098c1e3b377SZhao Yakui * When the boot option of "idle=halt" is added, halt 1099c1e3b377SZhao Yakui * is used for CPU IDLE. 1100c1e3b377SZhao Yakui * In such case C2/C3 is meaningless. So the max_cstate 1101c1e3b377SZhao Yakui * is set to one. 1102c1e3b377SZhao Yakui */ 1103c1e3b377SZhao Yakui max_cstate = 1; 1104c1e3b377SZhao Yakui } 11051da177e4SLinus Torvalds dmi_check_system(processor_power_dmi_table); 1106c1c30634SAlexey Starikovskiy max_cstate = acpi_processor_cstate_check(max_cstate); 11071da177e4SLinus Torvalds if (max_cstate < ACPI_C_STATES_MAX) 11084be44fcdSLen Brown printk(KERN_NOTICE 11094be44fcdSLen Brown "ACPI: processor limited to max C-state %d\n", 11104be44fcdSLen Brown max_cstate); 11111da177e4SLinus Torvalds first_run++; 11121da177e4SLinus Torvalds } 11131da177e4SLinus Torvalds 111402df8b93SVenkatesh Pallipadi if (!pr) 1115d550d98dSPatrick Mochel return -EINVAL; 111602df8b93SVenkatesh Pallipadi 1117cee324b1SAlexey Starikovskiy if (acpi_gbl_FADT.cst_control && !nocst) { 11184be44fcdSLen Brown status = 1119cee324b1SAlexey Starikovskiy acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8); 11201da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 1121a6fc6720SThomas Renninger ACPI_EXCEPTION((AE_INFO, status, 1122a6fc6720SThomas Renninger "Notifying BIOS of _CST ability failed")); 11231da177e4SLinus Torvalds } 11241da177e4SLinus Torvalds } 11251da177e4SLinus Torvalds 11261da177e4SLinus Torvalds acpi_processor_get_power_info(pr); 11274f86d3a8SLen Brown pr->flags.power_setup_done = 1; 11281da177e4SLinus Torvalds 11291da177e4SLinus Torvalds /* 11301da177e4SLinus Torvalds * Install the idle handler if processor power management is supported. 11311da177e4SLinus Torvalds * Note that we use previously set idle handler will be used on 11321da177e4SLinus Torvalds * platforms that only support C1. 11331da177e4SLinus Torvalds */ 113436a91358SVenkatesh Pallipadi if (pr->flags.power) { 11354f86d3a8SLen Brown acpi_processor_setup_cpuidle(pr); 11364f86d3a8SLen Brown if (cpuidle_register_device(&pr->power.dev)) 11374f86d3a8SLen Brown return -EIO; 11381da177e4SLinus Torvalds } 1139d550d98dSPatrick Mochel return 0; 11401da177e4SLinus Torvalds } 11411da177e4SLinus Torvalds 11424be44fcdSLen Brown int acpi_processor_power_exit(struct acpi_processor *pr, 11434be44fcdSLen Brown struct acpi_device *device) 11441da177e4SLinus Torvalds { 114536a91358SVenkatesh Pallipadi if (boot_option_idle_override) 114636a91358SVenkatesh Pallipadi return 0; 114736a91358SVenkatesh Pallipadi 11484f86d3a8SLen Brown cpuidle_unregister_device(&pr->power.dev); 11491da177e4SLinus Torvalds pr->flags.power_setup_done = 0; 11501da177e4SLinus Torvalds 1151d550d98dSPatrick Mochel return 0; 11521da177e4SLinus Torvalds } 1153