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 82d1896049SThomas Renninger static int disabled_by_idle_boot_param(void) 83d1896049SThomas Renninger { 84d1896049SThomas Renninger return boot_option_idle_override == IDLE_POLL || 85d1896049SThomas Renninger boot_option_idle_override == IDLE_FORCE_MWAIT || 86d1896049SThomas Renninger boot_option_idle_override == IDLE_HALT; 87d1896049SThomas Renninger } 88d1896049SThomas Renninger 891da177e4SLinus Torvalds /* 901da177e4SLinus Torvalds * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. 911da177e4SLinus Torvalds * For now disable this. Probably a bug somewhere else. 921da177e4SLinus Torvalds * 931da177e4SLinus Torvalds * To skip this limit, boot/load with a large max_cstate limit. 941da177e4SLinus Torvalds */ 951855256cSJeff Garzik static int set_max_cstate(const struct dmi_system_id *id) 961da177e4SLinus Torvalds { 971da177e4SLinus Torvalds if (max_cstate > ACPI_PROCESSOR_MAX_POWER) 981da177e4SLinus Torvalds return 0; 991da177e4SLinus Torvalds 1003d35600aSLen Brown printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." 1011da177e4SLinus Torvalds " Override with \"processor.max_cstate=%d\"\n", id->ident, 1023d35600aSLen Brown (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); 1031da177e4SLinus Torvalds 1043d35600aSLen Brown max_cstate = (long)id->driver_data; 1051da177e4SLinus Torvalds 1061da177e4SLinus Torvalds return 0; 1071da177e4SLinus Torvalds } 1081da177e4SLinus Torvalds 1097ded5689SAshok Raj /* Actually this shouldn't be __cpuinitdata, would be better to fix the 1107ded5689SAshok Raj callers to only run once -AK */ 1117ded5689SAshok Raj static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { 112335f16beSDavid Shaohua Li { set_max_cstate, "Clevo 5600D", { 113876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), 114876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, 115335f16beSDavid Shaohua Li (void *)2}, 116370d5cd8SArjan van de Ven { set_max_cstate, "Pavilion zv5000", { 117370d5cd8SArjan van de Ven DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 118370d5cd8SArjan van de Ven DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")}, 119370d5cd8SArjan van de Ven (void *)1}, 120370d5cd8SArjan van de Ven { set_max_cstate, "Asus L8400B", { 121370d5cd8SArjan van de Ven DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."), 122370d5cd8SArjan van de Ven DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")}, 123370d5cd8SArjan van de Ven (void *)1}, 1241da177e4SLinus Torvalds {}, 1251da177e4SLinus Torvalds }; 1261da177e4SLinus Torvalds 1274f86d3a8SLen Brown 1282e906655Svenkatesh.pallipadi@intel.com /* 1292e906655Svenkatesh.pallipadi@intel.com * Callers should disable interrupts before the call and enable 1302e906655Svenkatesh.pallipadi@intel.com * interrupts after return. 1312e906655Svenkatesh.pallipadi@intel.com */ 132ddc081a1SVenkatesh Pallipadi static void acpi_safe_halt(void) 133ddc081a1SVenkatesh Pallipadi { 134ddc081a1SVenkatesh Pallipadi current_thread_info()->status &= ~TS_POLLING; 135ddc081a1SVenkatesh Pallipadi /* 136ddc081a1SVenkatesh Pallipadi * TS_POLLING-cleared state must be visible before we 137ddc081a1SVenkatesh Pallipadi * test NEED_RESCHED: 138ddc081a1SVenkatesh Pallipadi */ 139ddc081a1SVenkatesh Pallipadi smp_mb(); 14071e93d15SVenki Pallipadi if (!need_resched()) { 141ddc081a1SVenkatesh Pallipadi safe_halt(); 14271e93d15SVenki Pallipadi local_irq_disable(); 14371e93d15SVenki Pallipadi } 144ddc081a1SVenkatesh Pallipadi current_thread_info()->status |= TS_POLLING; 145ddc081a1SVenkatesh Pallipadi } 146ddc081a1SVenkatesh Pallipadi 147169a0abbSThomas Gleixner #ifdef ARCH_APICTIMER_STOPS_ON_C3 148169a0abbSThomas Gleixner 149169a0abbSThomas Gleixner /* 150169a0abbSThomas Gleixner * Some BIOS implementations switch to C3 in the published C2 state. 151296d93cdSLinus Torvalds * This seems to be a common problem on AMD boxen, but other vendors 152296d93cdSLinus Torvalds * are affected too. We pick the most conservative approach: we assume 153296d93cdSLinus Torvalds * that the local APIC stops in both C2 and C3. 154169a0abbSThomas Gleixner */ 1557e275cc4SLen Brown static void lapic_timer_check_state(int state, struct acpi_processor *pr, 156169a0abbSThomas Gleixner struct acpi_processor_cx *cx) 157169a0abbSThomas Gleixner { 158169a0abbSThomas Gleixner struct acpi_processor_power *pwr = &pr->power; 159e585bef8SThomas Gleixner u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; 160169a0abbSThomas Gleixner 161db954b58SVenkatesh Pallipadi if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT)) 162db954b58SVenkatesh Pallipadi return; 163db954b58SVenkatesh Pallipadi 16402c68a02SLen Brown if (amd_e400_c1e_detected) 16587ad57baSShaohua Li type = ACPI_STATE_C1; 16687ad57baSShaohua Li 167169a0abbSThomas Gleixner /* 168169a0abbSThomas Gleixner * Check, if one of the previous states already marked the lapic 169169a0abbSThomas Gleixner * unstable 170169a0abbSThomas Gleixner */ 171169a0abbSThomas Gleixner if (pwr->timer_broadcast_on_state < state) 172169a0abbSThomas Gleixner return; 173169a0abbSThomas Gleixner 174e585bef8SThomas Gleixner if (cx->type >= type) 175169a0abbSThomas Gleixner pr->power.timer_broadcast_on_state = state; 176169a0abbSThomas Gleixner } 177169a0abbSThomas Gleixner 178918aae42SHidetoshi Seto static void __lapic_timer_propagate_broadcast(void *arg) 179169a0abbSThomas Gleixner { 180f833bab8SSuresh Siddha struct acpi_processor *pr = (struct acpi_processor *) arg; 181e9e2cdb4SThomas Gleixner unsigned long reason; 182e9e2cdb4SThomas Gleixner 183e9e2cdb4SThomas Gleixner reason = pr->power.timer_broadcast_on_state < INT_MAX ? 184e9e2cdb4SThomas Gleixner CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; 185e9e2cdb4SThomas Gleixner 186e9e2cdb4SThomas Gleixner clockevents_notify(reason, &pr->id); 187e9e2cdb4SThomas Gleixner } 188e9e2cdb4SThomas Gleixner 189918aae42SHidetoshi Seto static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) 190918aae42SHidetoshi Seto { 191918aae42SHidetoshi Seto smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast, 192918aae42SHidetoshi Seto (void *)pr, 1); 193918aae42SHidetoshi Seto } 194918aae42SHidetoshi Seto 195e9e2cdb4SThomas Gleixner /* Power(C) State timer broadcast control */ 1967e275cc4SLen Brown static void lapic_timer_state_broadcast(struct acpi_processor *pr, 197e9e2cdb4SThomas Gleixner struct acpi_processor_cx *cx, 198e9e2cdb4SThomas Gleixner int broadcast) 199e9e2cdb4SThomas Gleixner { 200e9e2cdb4SThomas Gleixner int state = cx - pr->power.states; 201e9e2cdb4SThomas Gleixner 202e9e2cdb4SThomas Gleixner if (state >= pr->power.timer_broadcast_on_state) { 203e9e2cdb4SThomas Gleixner unsigned long reason; 204e9e2cdb4SThomas Gleixner 205e9e2cdb4SThomas Gleixner reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER : 206e9e2cdb4SThomas Gleixner CLOCK_EVT_NOTIFY_BROADCAST_EXIT; 207e9e2cdb4SThomas Gleixner clockevents_notify(reason, &pr->id); 208e9e2cdb4SThomas Gleixner } 209169a0abbSThomas Gleixner } 210169a0abbSThomas Gleixner 211169a0abbSThomas Gleixner #else 212169a0abbSThomas Gleixner 2137e275cc4SLen Brown static void lapic_timer_check_state(int state, struct acpi_processor *pr, 214169a0abbSThomas Gleixner struct acpi_processor_cx *cstate) { } 2157e275cc4SLen Brown static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { } 2167e275cc4SLen Brown static void lapic_timer_state_broadcast(struct acpi_processor *pr, 217e9e2cdb4SThomas Gleixner struct acpi_processor_cx *cx, 218e9e2cdb4SThomas Gleixner int broadcast) 219e9e2cdb4SThomas Gleixner { 220e9e2cdb4SThomas Gleixner } 221169a0abbSThomas Gleixner 222169a0abbSThomas Gleixner #endif 223169a0abbSThomas Gleixner 224b04e7bdbSThomas Gleixner /* 225b04e7bdbSThomas Gleixner * Suspend / resume control 226b04e7bdbSThomas Gleixner */ 227b04e7bdbSThomas Gleixner static int acpi_idle_suspend; 228815ab0fdSLen Brown static u32 saved_bm_rld; 229815ab0fdSLen Brown 230815ab0fdSLen Brown static void acpi_idle_bm_rld_save(void) 231815ab0fdSLen Brown { 232815ab0fdSLen Brown acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld); 233815ab0fdSLen Brown } 234815ab0fdSLen Brown static void acpi_idle_bm_rld_restore(void) 235815ab0fdSLen Brown { 236815ab0fdSLen Brown u32 resumed_bm_rld; 237815ab0fdSLen Brown 238815ab0fdSLen Brown acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld); 239815ab0fdSLen Brown 240815ab0fdSLen Brown if (resumed_bm_rld != saved_bm_rld) 241815ab0fdSLen Brown acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld); 242815ab0fdSLen Brown } 243b04e7bdbSThomas Gleixner 244b04e7bdbSThomas Gleixner int acpi_processor_suspend(struct acpi_device * device, pm_message_t state) 245b04e7bdbSThomas Gleixner { 246815ab0fdSLen Brown if (acpi_idle_suspend == 1) 247815ab0fdSLen Brown return 0; 248815ab0fdSLen Brown 249815ab0fdSLen Brown acpi_idle_bm_rld_save(); 250b04e7bdbSThomas Gleixner acpi_idle_suspend = 1; 251b04e7bdbSThomas Gleixner return 0; 252b04e7bdbSThomas Gleixner } 253b04e7bdbSThomas Gleixner 254b04e7bdbSThomas Gleixner int acpi_processor_resume(struct acpi_device * device) 255b04e7bdbSThomas Gleixner { 256815ab0fdSLen Brown if (acpi_idle_suspend == 0) 257815ab0fdSLen Brown return 0; 258815ab0fdSLen Brown 259815ab0fdSLen Brown acpi_idle_bm_rld_restore(); 260b04e7bdbSThomas Gleixner acpi_idle_suspend = 0; 261b04e7bdbSThomas Gleixner return 0; 262b04e7bdbSThomas Gleixner } 263b04e7bdbSThomas Gleixner 264592913ecSJohn Stultz #if defined(CONFIG_X86) 265520daf72SLen Brown static void tsc_check_state(int state) 266ddb25f9aSAndi Kleen { 267ddb25f9aSAndi Kleen switch (boot_cpu_data.x86_vendor) { 268ddb25f9aSAndi Kleen case X86_VENDOR_AMD: 26940fb1715SVenki Pallipadi case X86_VENDOR_INTEL: 270ddb25f9aSAndi Kleen /* 271ddb25f9aSAndi Kleen * AMD Fam10h TSC will tick in all 272ddb25f9aSAndi Kleen * C/P/S0/S1 states when this bit is set. 273ddb25f9aSAndi Kleen */ 27440fb1715SVenki Pallipadi if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 275520daf72SLen Brown return; 27640fb1715SVenki Pallipadi 277ddb25f9aSAndi Kleen /*FALL THROUGH*/ 278ddb25f9aSAndi Kleen default: 279520daf72SLen Brown /* TSC could halt in idle, so notify users */ 280520daf72SLen Brown if (state > ACPI_STATE_C1) 281520daf72SLen Brown mark_tsc_unstable("TSC halts in idle"); 282ddb25f9aSAndi Kleen } 283ddb25f9aSAndi Kleen } 284520daf72SLen Brown #else 285520daf72SLen Brown static void tsc_check_state(int state) { return; } 286ddb25f9aSAndi Kleen #endif 287ddb25f9aSAndi Kleen 2881da177e4SLinus Torvalds static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 2891da177e4SLinus Torvalds { 2901da177e4SLinus Torvalds 2911da177e4SLinus Torvalds if (!pr) 292d550d98dSPatrick Mochel return -EINVAL; 2931da177e4SLinus Torvalds 2941da177e4SLinus Torvalds if (!pr->pblk) 295d550d98dSPatrick Mochel return -ENODEV; 2961da177e4SLinus Torvalds 2971da177e4SLinus Torvalds /* if info is obtained from pblk/fadt, type equals state */ 2981da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; 2991da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; 3001da177e4SLinus Torvalds 3014c033552SVenkatesh Pallipadi #ifndef CONFIG_HOTPLUG_CPU 3024c033552SVenkatesh Pallipadi /* 3034c033552SVenkatesh Pallipadi * Check for P_LVL2_UP flag before entering C2 and above on 3044c033552SVenkatesh Pallipadi * an SMP system. 3054c033552SVenkatesh Pallipadi */ 306ad71860aSAlexey Starikovskiy if ((num_online_cpus() > 1) && 307cee324b1SAlexey Starikovskiy !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 308d550d98dSPatrick Mochel return -ENODEV; 3094c033552SVenkatesh Pallipadi #endif 3104c033552SVenkatesh Pallipadi 3111da177e4SLinus Torvalds /* determine C2 and C3 address from pblk */ 3121da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; 3131da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; 3141da177e4SLinus Torvalds 3151da177e4SLinus Torvalds /* determine latencies from FADT */ 316cee324b1SAlexey Starikovskiy pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.C2latency; 317cee324b1SAlexey Starikovskiy pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.C3latency; 3181da177e4SLinus Torvalds 3195d76b6f6SLen Brown /* 3205d76b6f6SLen Brown * FADT specified C2 latency must be less than or equal to 3215d76b6f6SLen Brown * 100 microseconds. 3225d76b6f6SLen Brown */ 3235d76b6f6SLen Brown if (acpi_gbl_FADT.C2latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { 3245d76b6f6SLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, 3255d76b6f6SLen Brown "C2 latency too large [%d]\n", acpi_gbl_FADT.C2latency)); 3265d76b6f6SLen Brown /* invalidate C2 */ 3275d76b6f6SLen Brown pr->power.states[ACPI_STATE_C2].address = 0; 3285d76b6f6SLen Brown } 3295d76b6f6SLen Brown 330a6d72c18SLen Brown /* 331a6d72c18SLen Brown * FADT supplied C3 latency must be less than or equal to 332a6d72c18SLen Brown * 1000 microseconds. 333a6d72c18SLen Brown */ 334a6d72c18SLen Brown if (acpi_gbl_FADT.C3latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { 335a6d72c18SLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, 336a6d72c18SLen Brown "C3 latency too large [%d]\n", acpi_gbl_FADT.C3latency)); 337a6d72c18SLen Brown /* invalidate C3 */ 338a6d72c18SLen Brown pr->power.states[ACPI_STATE_C3].address = 0; 339a6d72c18SLen Brown } 340a6d72c18SLen Brown 3411da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 3421da177e4SLinus Torvalds "lvl2[0x%08x] lvl3[0x%08x]\n", 3431da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address, 3441da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address)); 3451da177e4SLinus Torvalds 346d550d98dSPatrick Mochel return 0; 3471da177e4SLinus Torvalds } 3481da177e4SLinus Torvalds 349991528d7SVenkatesh Pallipadi static int acpi_processor_get_power_info_default(struct acpi_processor *pr) 350acf05f4bSVenkatesh Pallipadi { 351991528d7SVenkatesh Pallipadi if (!pr->power.states[ACPI_STATE_C1].valid) { 352cf824788SJanosch Machowinski /* set the first C-State to C1 */ 353991528d7SVenkatesh Pallipadi /* all processors need to support C1 */ 354acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; 355acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].valid = 1; 3560fda6b40SVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; 357991528d7SVenkatesh Pallipadi } 358991528d7SVenkatesh Pallipadi /* the C0 state only exists as a filler in our array */ 359991528d7SVenkatesh Pallipadi pr->power.states[ACPI_STATE_C0].valid = 1; 360d550d98dSPatrick Mochel return 0; 361acf05f4bSVenkatesh Pallipadi } 362acf05f4bSVenkatesh Pallipadi 3631da177e4SLinus Torvalds static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) 3641da177e4SLinus Torvalds { 3651da177e4SLinus Torvalds acpi_status status = 0; 366439913ffSLin Ming u64 count; 367cf824788SJanosch Machowinski int current_count; 3681da177e4SLinus Torvalds int i; 3691da177e4SLinus Torvalds struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 3701da177e4SLinus Torvalds union acpi_object *cst; 3711da177e4SLinus Torvalds 3721da177e4SLinus Torvalds 3731da177e4SLinus Torvalds if (nocst) 374d550d98dSPatrick Mochel return -ENODEV; 3751da177e4SLinus Torvalds 376991528d7SVenkatesh Pallipadi current_count = 0; 3771da177e4SLinus Torvalds 3781da177e4SLinus Torvalds status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); 3791da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 3801da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); 381d550d98dSPatrick Mochel return -ENODEV; 3821da177e4SLinus Torvalds } 3831da177e4SLinus Torvalds 38450dd0969SJan Engelhardt cst = buffer.pointer; 3851da177e4SLinus Torvalds 3861da177e4SLinus Torvalds /* There must be at least 2 elements */ 3871da177e4SLinus Torvalds if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { 3886468463aSLen Brown printk(KERN_ERR PREFIX "not enough elements in _CST\n"); 3891da177e4SLinus Torvalds status = -EFAULT; 3901da177e4SLinus Torvalds goto end; 3911da177e4SLinus Torvalds } 3921da177e4SLinus Torvalds 3931da177e4SLinus Torvalds count = cst->package.elements[0].integer.value; 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds /* Validate number of power states. */ 3961da177e4SLinus Torvalds if (count < 1 || count != cst->package.count - 1) { 3976468463aSLen Brown printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); 3981da177e4SLinus Torvalds status = -EFAULT; 3991da177e4SLinus Torvalds goto end; 4001da177e4SLinus Torvalds } 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvalds /* Tell driver that at least _CST is supported. */ 4031da177e4SLinus Torvalds pr->flags.has_cst = 1; 4041da177e4SLinus Torvalds 4051da177e4SLinus Torvalds for (i = 1; i <= count; i++) { 4061da177e4SLinus Torvalds union acpi_object *element; 4071da177e4SLinus Torvalds union acpi_object *obj; 4081da177e4SLinus Torvalds struct acpi_power_register *reg; 4091da177e4SLinus Torvalds struct acpi_processor_cx cx; 4101da177e4SLinus Torvalds 4111da177e4SLinus Torvalds memset(&cx, 0, sizeof(cx)); 4121da177e4SLinus Torvalds 41350dd0969SJan Engelhardt element = &(cst->package.elements[i]); 4141da177e4SLinus Torvalds if (element->type != ACPI_TYPE_PACKAGE) 4151da177e4SLinus Torvalds continue; 4161da177e4SLinus Torvalds 4171da177e4SLinus Torvalds if (element->package.count != 4) 4181da177e4SLinus Torvalds continue; 4191da177e4SLinus Torvalds 42050dd0969SJan Engelhardt obj = &(element->package.elements[0]); 4211da177e4SLinus Torvalds 4221da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_BUFFER) 4231da177e4SLinus Torvalds continue; 4241da177e4SLinus Torvalds 4251da177e4SLinus Torvalds reg = (struct acpi_power_register *)obj->buffer.pointer; 4261da177e4SLinus Torvalds 4271da177e4SLinus Torvalds if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && 4281da177e4SLinus Torvalds (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) 4291da177e4SLinus Torvalds continue; 4301da177e4SLinus Torvalds 4311da177e4SLinus Torvalds /* There should be an easy way to extract an integer... */ 43250dd0969SJan Engelhardt obj = &(element->package.elements[1]); 4331da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4341da177e4SLinus Torvalds continue; 4351da177e4SLinus Torvalds 4361da177e4SLinus Torvalds cx.type = obj->integer.value; 437991528d7SVenkatesh Pallipadi /* 438991528d7SVenkatesh Pallipadi * Some buggy BIOSes won't list C1 in _CST - 439991528d7SVenkatesh Pallipadi * Let acpi_processor_get_power_info_default() handle them later 440991528d7SVenkatesh Pallipadi */ 441991528d7SVenkatesh Pallipadi if (i == 1 && cx.type != ACPI_STATE_C1) 442991528d7SVenkatesh Pallipadi current_count++; 4431da177e4SLinus Torvalds 444991528d7SVenkatesh Pallipadi cx.address = reg->address; 445991528d7SVenkatesh Pallipadi cx.index = current_count + 1; 4461da177e4SLinus Torvalds 447bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_SYSTEMIO; 448991528d7SVenkatesh Pallipadi if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { 449991528d7SVenkatesh Pallipadi if (acpi_processor_ffh_cstate_probe 450991528d7SVenkatesh Pallipadi (pr->id, &cx, reg) == 0) { 451bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_FFH; 452bc71bec9Svenkatesh.pallipadi@intel.com } else if (cx.type == ACPI_STATE_C1) { 453991528d7SVenkatesh Pallipadi /* 454991528d7SVenkatesh Pallipadi * C1 is a special case where FIXED_HARDWARE 455991528d7SVenkatesh Pallipadi * can be handled in non-MWAIT way as well. 456991528d7SVenkatesh Pallipadi * In that case, save this _CST entry info. 457991528d7SVenkatesh Pallipadi * Otherwise, ignore this info and continue. 458991528d7SVenkatesh Pallipadi */ 459bc71bec9Svenkatesh.pallipadi@intel.com cx.entry_method = ACPI_CSTATE_HALT; 4604fcb2fcdSVenkatesh Pallipadi snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); 461bc71bec9Svenkatesh.pallipadi@intel.com } else { 4621da177e4SLinus Torvalds continue; 463991528d7SVenkatesh Pallipadi } 464da5e09a1SZhao Yakui if (cx.type == ACPI_STATE_C1 && 465d1896049SThomas Renninger (boot_option_idle_override == IDLE_NOMWAIT)) { 466c1e3b377SZhao Yakui /* 467c1e3b377SZhao Yakui * In most cases the C1 space_id obtained from 468c1e3b377SZhao Yakui * _CST object is FIXED_HARDWARE access mode. 469c1e3b377SZhao Yakui * But when the option of idle=halt is added, 470c1e3b377SZhao Yakui * the entry_method type should be changed from 471c1e3b377SZhao Yakui * CSTATE_FFH to CSTATE_HALT. 472da5e09a1SZhao Yakui * When the option of idle=nomwait is added, 473da5e09a1SZhao Yakui * the C1 entry_method type should be 474da5e09a1SZhao Yakui * CSTATE_HALT. 475c1e3b377SZhao Yakui */ 476c1e3b377SZhao Yakui cx.entry_method = ACPI_CSTATE_HALT; 477c1e3b377SZhao Yakui snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT"); 478c1e3b377SZhao Yakui } 4794fcb2fcdSVenkatesh Pallipadi } else { 4804fcb2fcdSVenkatesh Pallipadi snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x", 4814fcb2fcdSVenkatesh Pallipadi cx.address); 482991528d7SVenkatesh Pallipadi } 4831da177e4SLinus Torvalds 4840fda6b40SVenkatesh Pallipadi if (cx.type == ACPI_STATE_C1) { 4850fda6b40SVenkatesh Pallipadi cx.valid = 1; 4860fda6b40SVenkatesh Pallipadi } 4874fcb2fcdSVenkatesh Pallipadi 48850dd0969SJan Engelhardt obj = &(element->package.elements[2]); 4891da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4901da177e4SLinus Torvalds continue; 4911da177e4SLinus Torvalds 4921da177e4SLinus Torvalds cx.latency = obj->integer.value; 4931da177e4SLinus Torvalds 49450dd0969SJan Engelhardt obj = &(element->package.elements[3]); 4951da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 4961da177e4SLinus Torvalds continue; 4971da177e4SLinus Torvalds 4981da177e4SLinus Torvalds cx.power = obj->integer.value; 4991da177e4SLinus Torvalds 500cf824788SJanosch Machowinski current_count++; 501cf824788SJanosch Machowinski memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); 502cf824788SJanosch Machowinski 503cf824788SJanosch Machowinski /* 504cf824788SJanosch Machowinski * We support total ACPI_PROCESSOR_MAX_POWER - 1 505cf824788SJanosch Machowinski * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) 506cf824788SJanosch Machowinski */ 507cf824788SJanosch Machowinski if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { 508cf824788SJanosch Machowinski printk(KERN_WARNING 509cf824788SJanosch Machowinski "Limiting number of power states to max (%d)\n", 510cf824788SJanosch Machowinski ACPI_PROCESSOR_MAX_POWER); 511cf824788SJanosch Machowinski printk(KERN_WARNING 512cf824788SJanosch Machowinski "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); 513cf824788SJanosch Machowinski break; 514cf824788SJanosch Machowinski } 5151da177e4SLinus Torvalds } 5161da177e4SLinus Torvalds 5174be44fcdSLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", 518cf824788SJanosch Machowinski current_count)); 5191da177e4SLinus Torvalds 5201da177e4SLinus Torvalds /* Validate number of power states discovered */ 521cf824788SJanosch Machowinski if (current_count < 2) 5226d93c648SVenkatesh Pallipadi status = -EFAULT; 5231da177e4SLinus Torvalds 5241da177e4SLinus Torvalds end: 52502438d87SLen Brown kfree(buffer.pointer); 5261da177e4SLinus Torvalds 527d550d98dSPatrick Mochel return status; 5281da177e4SLinus Torvalds } 5291da177e4SLinus Torvalds 5304be44fcdSLen Brown static void acpi_processor_power_verify_c3(struct acpi_processor *pr, 5311da177e4SLinus Torvalds struct acpi_processor_cx *cx) 5321da177e4SLinus Torvalds { 533ee1ca48fSPallipadi, Venkatesh static int bm_check_flag = -1; 534ee1ca48fSPallipadi, Venkatesh static int bm_control_flag = -1; 53502df8b93SVenkatesh Pallipadi 5361da177e4SLinus Torvalds 5371da177e4SLinus Torvalds if (!cx->address) 538d550d98dSPatrick Mochel return; 5391da177e4SLinus Torvalds 5401da177e4SLinus Torvalds /* 5411da177e4SLinus Torvalds * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) 5421da177e4SLinus Torvalds * DMA transfers are used by any ISA device to avoid livelock. 5431da177e4SLinus Torvalds * Note that we could disable Type-F DMA (as recommended by 5441da177e4SLinus Torvalds * the erratum), but this is known to disrupt certain ISA 5451da177e4SLinus Torvalds * devices thus we take the conservative approach. 5461da177e4SLinus Torvalds */ 5471da177e4SLinus Torvalds else if (errata.piix4.fdma) { 5481da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 5491da177e4SLinus Torvalds "C3 not supported on PIIX4 with Type-F DMA\n")); 550d550d98dSPatrick Mochel return; 5511da177e4SLinus Torvalds } 5521da177e4SLinus Torvalds 55302df8b93SVenkatesh Pallipadi /* All the logic here assumes flags.bm_check is same across all CPUs */ 554ee1ca48fSPallipadi, Venkatesh if (bm_check_flag == -1) { 55502df8b93SVenkatesh Pallipadi /* Determine whether bm_check is needed based on CPU */ 55602df8b93SVenkatesh Pallipadi acpi_processor_power_init_bm_check(&(pr->flags), pr->id); 55702df8b93SVenkatesh Pallipadi bm_check_flag = pr->flags.bm_check; 558ee1ca48fSPallipadi, Venkatesh bm_control_flag = pr->flags.bm_control; 55902df8b93SVenkatesh Pallipadi } else { 56002df8b93SVenkatesh Pallipadi pr->flags.bm_check = bm_check_flag; 561ee1ca48fSPallipadi, Venkatesh pr->flags.bm_control = bm_control_flag; 56202df8b93SVenkatesh Pallipadi } 56302df8b93SVenkatesh Pallipadi 56402df8b93SVenkatesh Pallipadi if (pr->flags.bm_check) { 56502df8b93SVenkatesh Pallipadi if (!pr->flags.bm_control) { 566ed3110efSVenki Pallipadi if (pr->flags.has_cst != 1) { 567ed3110efSVenki Pallipadi /* bus mastering control is necessary */ 56802df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 569ed3110efSVenki Pallipadi "C3 support requires BM control\n")); 570ed3110efSVenki Pallipadi return; 571ed3110efSVenki Pallipadi } else { 572ed3110efSVenki Pallipadi /* Here we enter C3 without bus mastering */ 573ed3110efSVenki Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 574ed3110efSVenki Pallipadi "C3 support without BM control\n")); 575ed3110efSVenki Pallipadi } 57602df8b93SVenkatesh Pallipadi } 57702df8b93SVenkatesh Pallipadi } else { 57802df8b93SVenkatesh Pallipadi /* 57902df8b93SVenkatesh Pallipadi * WBINVD should be set in fadt, for C3 state to be 58002df8b93SVenkatesh Pallipadi * supported on when bm_check is not required. 58102df8b93SVenkatesh Pallipadi */ 582cee324b1SAlexey Starikovskiy if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { 58302df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 58402df8b93SVenkatesh Pallipadi "Cache invalidation should work properly" 58502df8b93SVenkatesh Pallipadi " for C3 to be enabled on SMP systems\n")); 586d550d98dSPatrick Mochel return; 58702df8b93SVenkatesh Pallipadi } 58802df8b93SVenkatesh Pallipadi } 58902df8b93SVenkatesh Pallipadi 5901da177e4SLinus Torvalds /* 5911da177e4SLinus Torvalds * Otherwise we've met all of our C3 requirements. 5921da177e4SLinus Torvalds * Normalize the C3 latency to expidite policy. Enable 5931da177e4SLinus Torvalds * checking of bus mastering status (bm_check) so we can 5941da177e4SLinus Torvalds * use this in our C3 policy 5951da177e4SLinus Torvalds */ 5961da177e4SLinus Torvalds cx->valid = 1; 5974f86d3a8SLen Brown 5984f86d3a8SLen Brown cx->latency_ticks = cx->latency; 59931878dd8SLen Brown /* 60031878dd8SLen Brown * On older chipsets, BM_RLD needs to be set 60131878dd8SLen Brown * in order for Bus Master activity to wake the 60231878dd8SLen Brown * system from C3. Newer chipsets handle DMA 60331878dd8SLen Brown * during C3 automatically and BM_RLD is a NOP. 60431878dd8SLen Brown * In either case, the proper way to 60531878dd8SLen Brown * handle BM_RLD is to set it and leave it set. 60631878dd8SLen Brown */ 60750ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); 6081da177e4SLinus Torvalds 609d550d98dSPatrick Mochel return; 6101da177e4SLinus Torvalds } 6111da177e4SLinus Torvalds 6121da177e4SLinus Torvalds static int acpi_processor_power_verify(struct acpi_processor *pr) 6131da177e4SLinus Torvalds { 6141da177e4SLinus Torvalds unsigned int i; 6151da177e4SLinus Torvalds unsigned int working = 0; 6166eb0a0fdSVenkatesh Pallipadi 617169a0abbSThomas Gleixner pr->power.timer_broadcast_on_state = INT_MAX; 6186eb0a0fdSVenkatesh Pallipadi 619a0bf284bSLen Brown for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 6201da177e4SLinus Torvalds struct acpi_processor_cx *cx = &pr->power.states[i]; 6211da177e4SLinus Torvalds 6221da177e4SLinus Torvalds switch (cx->type) { 6231da177e4SLinus Torvalds case ACPI_STATE_C1: 6241da177e4SLinus Torvalds cx->valid = 1; 6251da177e4SLinus Torvalds break; 6261da177e4SLinus Torvalds 6271da177e4SLinus Torvalds case ACPI_STATE_C2: 628d22edd29SLen Brown if (!cx->address) 629d22edd29SLen Brown break; 630d22edd29SLen Brown cx->valid = 1; 631d22edd29SLen Brown cx->latency_ticks = cx->latency; /* Normalize latency */ 6321da177e4SLinus Torvalds break; 6331da177e4SLinus Torvalds 6341da177e4SLinus Torvalds case ACPI_STATE_C3: 6351da177e4SLinus Torvalds acpi_processor_power_verify_c3(pr, cx); 6361da177e4SLinus Torvalds break; 6371da177e4SLinus Torvalds } 6387e275cc4SLen Brown if (!cx->valid) 6397e275cc4SLen Brown continue; 6401da177e4SLinus Torvalds 6417e275cc4SLen Brown lapic_timer_check_state(i, pr, cx); 6427e275cc4SLen Brown tsc_check_state(cx->type); 6431da177e4SLinus Torvalds working++; 6441da177e4SLinus Torvalds } 6451da177e4SLinus Torvalds 646918aae42SHidetoshi Seto lapic_timer_propagate_broadcast(pr); 647bd663347SAndi Kleen 6481da177e4SLinus Torvalds return (working); 6491da177e4SLinus Torvalds } 6501da177e4SLinus Torvalds 6514be44fcdSLen Brown static int acpi_processor_get_power_info(struct acpi_processor *pr) 6521da177e4SLinus Torvalds { 6531da177e4SLinus Torvalds unsigned int i; 6541da177e4SLinus Torvalds int result; 6551da177e4SLinus Torvalds 6561da177e4SLinus Torvalds 6571da177e4SLinus Torvalds /* NOTE: the idle thread may not be running while calling 6581da177e4SLinus Torvalds * this function */ 6591da177e4SLinus Torvalds 660991528d7SVenkatesh Pallipadi /* Zero initialize all the C-states info. */ 661991528d7SVenkatesh Pallipadi memset(pr->power.states, 0, sizeof(pr->power.states)); 662991528d7SVenkatesh Pallipadi 6631da177e4SLinus Torvalds result = acpi_processor_get_power_info_cst(pr); 6646d93c648SVenkatesh Pallipadi if (result == -ENODEV) 665c5a114f1SDarrick J. Wong result = acpi_processor_get_power_info_fadt(pr); 6666d93c648SVenkatesh Pallipadi 667991528d7SVenkatesh Pallipadi if (result) 668991528d7SVenkatesh Pallipadi return result; 669991528d7SVenkatesh Pallipadi 670991528d7SVenkatesh Pallipadi acpi_processor_get_power_info_default(pr); 671991528d7SVenkatesh Pallipadi 672cf824788SJanosch Machowinski pr->power.count = acpi_processor_power_verify(pr); 6731da177e4SLinus Torvalds 6741da177e4SLinus Torvalds /* 6751da177e4SLinus Torvalds * if one state of type C2 or C3 is available, mark this 6761da177e4SLinus Torvalds * CPU as being "idle manageable" 6771da177e4SLinus Torvalds */ 6781da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 679acf05f4bSVenkatesh Pallipadi if (pr->power.states[i].valid) { 6801da177e4SLinus Torvalds pr->power.count = i; 6812203d6edSLinus Torvalds if (pr->power.states[i].type >= ACPI_STATE_C2) 6821da177e4SLinus Torvalds pr->flags.power = 1; 6831da177e4SLinus Torvalds } 684acf05f4bSVenkatesh Pallipadi } 6851da177e4SLinus Torvalds 686d550d98dSPatrick Mochel return 0; 6871da177e4SLinus Torvalds } 6881da177e4SLinus Torvalds 6894f86d3a8SLen Brown /** 6904f86d3a8SLen Brown * acpi_idle_bm_check - checks if bus master activity was detected 6914f86d3a8SLen Brown */ 6924f86d3a8SLen Brown static int acpi_idle_bm_check(void) 6934f86d3a8SLen Brown { 6944f86d3a8SLen Brown u32 bm_status = 0; 6954f86d3a8SLen Brown 696d3e7e99fSLen Brown if (bm_check_disable) 697d3e7e99fSLen Brown return 0; 698d3e7e99fSLen Brown 69950ffba1bSBob Moore acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); 7004f86d3a8SLen Brown if (bm_status) 70150ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); 7024f86d3a8SLen Brown /* 7034f86d3a8SLen Brown * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect 7044f86d3a8SLen Brown * the true state of bus mastering activity; forcing us to 7054f86d3a8SLen Brown * manually check the BMIDEA bit of each IDE channel. 7064f86d3a8SLen Brown */ 7074f86d3a8SLen Brown else if (errata.piix4.bmisx) { 7084f86d3a8SLen Brown if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) 7094f86d3a8SLen Brown || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) 7104f86d3a8SLen Brown bm_status = 1; 7114f86d3a8SLen Brown } 7124f86d3a8SLen Brown return bm_status; 7134f86d3a8SLen Brown } 7144f86d3a8SLen Brown 7154f86d3a8SLen Brown /** 7164f86d3a8SLen Brown * acpi_idle_do_entry - a helper function that does C2 and C3 type entry 7174f86d3a8SLen Brown * @cx: cstate data 718bc71bec9Svenkatesh.pallipadi@intel.com * 719bc71bec9Svenkatesh.pallipadi@intel.com * Caller disables interrupt before call and enables interrupt after return. 7204f86d3a8SLen Brown */ 7214f86d3a8SLen Brown static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) 7224f86d3a8SLen Brown { 723dcf30997SSteven Rostedt /* Don't trace irqs off for idle */ 724dcf30997SSteven Rostedt stop_critical_timings(); 725bc71bec9Svenkatesh.pallipadi@intel.com if (cx->entry_method == ACPI_CSTATE_FFH) { 7264f86d3a8SLen Brown /* Call into architectural FFH based C-state */ 7274f86d3a8SLen Brown acpi_processor_ffh_cstate_enter(cx); 728bc71bec9Svenkatesh.pallipadi@intel.com } else if (cx->entry_method == ACPI_CSTATE_HALT) { 729bc71bec9Svenkatesh.pallipadi@intel.com acpi_safe_halt(); 7304f86d3a8SLen Brown } else { 7314f86d3a8SLen Brown /* IO port based C-state */ 7324f86d3a8SLen Brown inb(cx->address); 7334f86d3a8SLen Brown /* Dummy wait op - must do something useless after P_LVL2 read 7344f86d3a8SLen Brown because chipsets cannot guarantee that STPCLK# signal 7354f86d3a8SLen Brown gets asserted in time to freeze execution properly. */ 736cfa806f0SAndi Kleen inl(acpi_gbl_FADT.xpm_timer_block.address); 7374f86d3a8SLen Brown } 738dcf30997SSteven Rostedt start_critical_timings(); 7394f86d3a8SLen Brown } 7404f86d3a8SLen Brown 7414f86d3a8SLen Brown /** 7424f86d3a8SLen Brown * acpi_idle_enter_c1 - enters an ACPI C1 state-type 7434f86d3a8SLen Brown * @dev: the target CPU 7444f86d3a8SLen Brown * @state: the state data 7454f86d3a8SLen Brown * 7464f86d3a8SLen Brown * This is equivalent to the HALT instruction. 7474f86d3a8SLen Brown */ 7484f86d3a8SLen Brown static int acpi_idle_enter_c1(struct cpuidle_device *dev, 7494f86d3a8SLen Brown struct cpuidle_state *state) 7504f86d3a8SLen Brown { 751ff69f2bbSalex.shi ktime_t kt1, kt2; 752ff69f2bbSalex.shi s64 idle_time; 7534f86d3a8SLen Brown struct acpi_processor *pr; 7544f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 7559b12e18cSvenkatesh.pallipadi@intel.com 7564a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 7574f86d3a8SLen Brown 7584f86d3a8SLen Brown if (unlikely(!pr)) 7594f86d3a8SLen Brown return 0; 7604f86d3a8SLen Brown 7612e906655Svenkatesh.pallipadi@intel.com local_irq_disable(); 762b077fbadSVenkatesh Pallipadi 763b077fbadSVenkatesh Pallipadi /* Do not access any ACPI IO ports in suspend path */ 764b077fbadSVenkatesh Pallipadi if (acpi_idle_suspend) { 765b077fbadSVenkatesh Pallipadi local_irq_enable(); 7667d60e8abSShaohua Li cpu_relax(); 767b077fbadSVenkatesh Pallipadi return 0; 768b077fbadSVenkatesh Pallipadi } 769b077fbadSVenkatesh Pallipadi 7707e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 771ff69f2bbSalex.shi kt1 = ktime_get_real(); 772bc71bec9Svenkatesh.pallipadi@intel.com acpi_idle_do_entry(cx); 773ff69f2bbSalex.shi kt2 = ktime_get_real(); 774ff69f2bbSalex.shi idle_time = ktime_to_us(ktime_sub(kt2, kt1)); 7754f86d3a8SLen Brown 7762e906655Svenkatesh.pallipadi@intel.com local_irq_enable(); 7774f86d3a8SLen Brown cx->usage++; 7787e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 7794f86d3a8SLen Brown 780ff69f2bbSalex.shi return idle_time; 7814f86d3a8SLen Brown } 7824f86d3a8SLen Brown 7834f86d3a8SLen Brown /** 7844f86d3a8SLen Brown * acpi_idle_enter_simple - enters an ACPI state without BM handling 7854f86d3a8SLen Brown * @dev: the target CPU 7864f86d3a8SLen Brown * @state: the state data 7874f86d3a8SLen Brown */ 7884f86d3a8SLen Brown static int acpi_idle_enter_simple(struct cpuidle_device *dev, 7894f86d3a8SLen Brown struct cpuidle_state *state) 7904f86d3a8SLen Brown { 7914f86d3a8SLen Brown struct acpi_processor *pr; 7924f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 793ff69f2bbSalex.shi ktime_t kt1, kt2; 7942da513f5SVenkatesh Pallipadi s64 idle_time_ns; 795ff69f2bbSalex.shi s64 idle_time; 79650629118SVenkatesh Pallipadi 7974a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 7984f86d3a8SLen Brown 7994f86d3a8SLen Brown if (unlikely(!pr)) 8004f86d3a8SLen Brown return 0; 8014f86d3a8SLen Brown 802e196441bSLen Brown if (acpi_idle_suspend) 803e196441bSLen Brown return(acpi_idle_enter_c1(dev, state)); 804e196441bSLen Brown 8054f86d3a8SLen Brown local_irq_disable(); 80602cf4f98SLen Brown 807d306ebc2SPallipadi, Venkatesh if (cx->entry_method != ACPI_CSTATE_FFH) { 8084f86d3a8SLen Brown current_thread_info()->status &= ~TS_POLLING; 8094f86d3a8SLen Brown /* 8104f86d3a8SLen Brown * TS_POLLING-cleared state must be visible before we test 8114f86d3a8SLen Brown * NEED_RESCHED: 8124f86d3a8SLen Brown */ 8134f86d3a8SLen Brown smp_mb(); 8144f86d3a8SLen Brown 8154f86d3a8SLen Brown if (unlikely(need_resched())) { 8164f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 8174f86d3a8SLen Brown local_irq_enable(); 8184f86d3a8SLen Brown return 0; 8194f86d3a8SLen Brown } 82002cf4f98SLen Brown } 8214f86d3a8SLen Brown 822e17bcb43SThomas Gleixner /* 823e17bcb43SThomas Gleixner * Must be done before busmaster disable as we might need to 824e17bcb43SThomas Gleixner * access HPET ! 825e17bcb43SThomas Gleixner */ 8267e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 827e17bcb43SThomas Gleixner 8284f86d3a8SLen Brown if (cx->type == ACPI_STATE_C3) 8294f86d3a8SLen Brown ACPI_FLUSH_CPU_CACHE(); 8304f86d3a8SLen Brown 831ff69f2bbSalex.shi kt1 = ktime_get_real(); 83250629118SVenkatesh Pallipadi /* Tell the scheduler that we are going deep-idle: */ 83350629118SVenkatesh Pallipadi sched_clock_idle_sleep_event(); 8344f86d3a8SLen Brown acpi_idle_do_entry(cx); 835ff69f2bbSalex.shi kt2 = ktime_get_real(); 8362da513f5SVenkatesh Pallipadi idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1)); 8372da513f5SVenkatesh Pallipadi idle_time = idle_time_ns; 8382da513f5SVenkatesh Pallipadi do_div(idle_time, NSEC_PER_USEC); 8394f86d3a8SLen Brown 84050629118SVenkatesh Pallipadi /* Tell the scheduler how much we idled: */ 8412da513f5SVenkatesh Pallipadi sched_clock_idle_wakeup_event(idle_time_ns); 8424f86d3a8SLen Brown 8434f86d3a8SLen Brown local_irq_enable(); 84402cf4f98SLen Brown if (cx->entry_method != ACPI_CSTATE_FFH) 8454f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 8464f86d3a8SLen Brown 8474f86d3a8SLen Brown cx->usage++; 8484f86d3a8SLen Brown 8497e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 850bceefad5SVenkatesh Pallipadi cx->time += idle_time; 851ff69f2bbSalex.shi return idle_time; 8524f86d3a8SLen Brown } 8534f86d3a8SLen Brown 8544f86d3a8SLen Brown static int c3_cpu_count; 8554f86d3a8SLen Brown static DEFINE_SPINLOCK(c3_lock); 8564f86d3a8SLen Brown 8574f86d3a8SLen Brown /** 8584f86d3a8SLen Brown * acpi_idle_enter_bm - enters C3 with proper BM handling 8594f86d3a8SLen Brown * @dev: the target CPU 8604f86d3a8SLen Brown * @state: the state data 8614f86d3a8SLen Brown * 8624f86d3a8SLen Brown * If BM is detected, the deepest non-C3 idle state is entered instead. 8634f86d3a8SLen Brown */ 8644f86d3a8SLen Brown static int acpi_idle_enter_bm(struct cpuidle_device *dev, 8654f86d3a8SLen Brown struct cpuidle_state *state) 8664f86d3a8SLen Brown { 8674f86d3a8SLen Brown struct acpi_processor *pr; 8684f86d3a8SLen Brown struct acpi_processor_cx *cx = cpuidle_get_statedata(state); 869ff69f2bbSalex.shi ktime_t kt1, kt2; 8702da513f5SVenkatesh Pallipadi s64 idle_time_ns; 871ff69f2bbSalex.shi s64 idle_time; 872ff69f2bbSalex.shi 87350629118SVenkatesh Pallipadi 8744a6f4fe8SChristoph Lameter pr = __this_cpu_read(processors); 8754f86d3a8SLen Brown 8764f86d3a8SLen Brown if (unlikely(!pr)) 8774f86d3a8SLen Brown return 0; 8784f86d3a8SLen Brown 879e196441bSLen Brown if (acpi_idle_suspend) 880e196441bSLen Brown return(acpi_idle_enter_c1(dev, state)); 881e196441bSLen Brown 882718be4aaSLen Brown if (!cx->bm_sts_skip && acpi_idle_bm_check()) { 883ddc081a1SVenkatesh Pallipadi if (dev->safe_state) { 884addbad46SVenkatesh Pallipadi dev->last_state = dev->safe_state; 885ddc081a1SVenkatesh Pallipadi return dev->safe_state->enter(dev, dev->safe_state); 886ddc081a1SVenkatesh Pallipadi } else { 8872e906655Svenkatesh.pallipadi@intel.com local_irq_disable(); 888ddc081a1SVenkatesh Pallipadi acpi_safe_halt(); 8892e906655Svenkatesh.pallipadi@intel.com local_irq_enable(); 890ddc081a1SVenkatesh Pallipadi return 0; 891ddc081a1SVenkatesh Pallipadi } 892ddc081a1SVenkatesh Pallipadi } 893ddc081a1SVenkatesh Pallipadi 8944f86d3a8SLen Brown local_irq_disable(); 89502cf4f98SLen Brown 896d306ebc2SPallipadi, Venkatesh if (cx->entry_method != ACPI_CSTATE_FFH) { 8974f86d3a8SLen Brown current_thread_info()->status &= ~TS_POLLING; 8984f86d3a8SLen Brown /* 8994f86d3a8SLen Brown * TS_POLLING-cleared state must be visible before we test 9004f86d3a8SLen Brown * NEED_RESCHED: 9014f86d3a8SLen Brown */ 9024f86d3a8SLen Brown smp_mb(); 9034f86d3a8SLen Brown 9044f86d3a8SLen Brown if (unlikely(need_resched())) { 9054f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 9064f86d3a8SLen Brown local_irq_enable(); 9074f86d3a8SLen Brown return 0; 9084f86d3a8SLen Brown } 90902cf4f98SLen Brown } 9104f86d3a8SLen Brown 911996520c1SVenki Pallipadi acpi_unlazy_tlb(smp_processor_id()); 912996520c1SVenki Pallipadi 91350629118SVenkatesh Pallipadi /* Tell the scheduler that we are going deep-idle: */ 91450629118SVenkatesh Pallipadi sched_clock_idle_sleep_event(); 9154f86d3a8SLen Brown /* 9164f86d3a8SLen Brown * Must be done before busmaster disable as we might need to 9174f86d3a8SLen Brown * access HPET ! 9184f86d3a8SLen Brown */ 9197e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 1); 9204f86d3a8SLen Brown 921f461ddeaSLen Brown kt1 = ktime_get_real(); 922c9c860e5SVenkatesh Pallipadi /* 923c9c860e5SVenkatesh Pallipadi * disable bus master 924c9c860e5SVenkatesh Pallipadi * bm_check implies we need ARB_DIS 925c9c860e5SVenkatesh Pallipadi * !bm_check implies we need cache flush 926c9c860e5SVenkatesh Pallipadi * bm_control implies whether we can do ARB_DIS 927c9c860e5SVenkatesh Pallipadi * 928c9c860e5SVenkatesh Pallipadi * That leaves a case where bm_check is set and bm_control is 929c9c860e5SVenkatesh Pallipadi * not set. In that case we cannot do much, we enter C3 930c9c860e5SVenkatesh Pallipadi * without doing anything. 931c9c860e5SVenkatesh Pallipadi */ 932c9c860e5SVenkatesh Pallipadi if (pr->flags.bm_check && pr->flags.bm_control) { 9334f86d3a8SLen Brown spin_lock(&c3_lock); 9344f86d3a8SLen Brown c3_cpu_count++; 9354f86d3a8SLen Brown /* Disable bus master arbitration when all CPUs are in C3 */ 9364f86d3a8SLen Brown if (c3_cpu_count == num_online_cpus()) 93750ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); 9384f86d3a8SLen Brown spin_unlock(&c3_lock); 939c9c860e5SVenkatesh Pallipadi } else if (!pr->flags.bm_check) { 940c9c860e5SVenkatesh Pallipadi ACPI_FLUSH_CPU_CACHE(); 941c9c860e5SVenkatesh Pallipadi } 9424f86d3a8SLen Brown 9434f86d3a8SLen Brown acpi_idle_do_entry(cx); 9444f86d3a8SLen Brown 9454f86d3a8SLen Brown /* Re-enable bus master arbitration */ 946c9c860e5SVenkatesh Pallipadi if (pr->flags.bm_check && pr->flags.bm_control) { 947c9c860e5SVenkatesh Pallipadi spin_lock(&c3_lock); 94850ffba1bSBob Moore acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); 9494f86d3a8SLen Brown c3_cpu_count--; 9504f86d3a8SLen Brown spin_unlock(&c3_lock); 9514f86d3a8SLen Brown } 952f461ddeaSLen Brown kt2 = ktime_get_real(); 953157317baSZhao Yakui idle_time_ns = ktime_to_ns(ktime_sub(kt2, kt1)); 9542da513f5SVenkatesh Pallipadi idle_time = idle_time_ns; 9552da513f5SVenkatesh Pallipadi do_div(idle_time, NSEC_PER_USEC); 9564f86d3a8SLen Brown 95750629118SVenkatesh Pallipadi /* Tell the scheduler how much we idled: */ 9582da513f5SVenkatesh Pallipadi sched_clock_idle_wakeup_event(idle_time_ns); 9594f86d3a8SLen Brown 9604f86d3a8SLen Brown local_irq_enable(); 96102cf4f98SLen Brown if (cx->entry_method != ACPI_CSTATE_FFH) 9624f86d3a8SLen Brown current_thread_info()->status |= TS_POLLING; 9634f86d3a8SLen Brown 9644f86d3a8SLen Brown cx->usage++; 9654f86d3a8SLen Brown 9667e275cc4SLen Brown lapic_timer_state_broadcast(pr, cx, 0); 967bceefad5SVenkatesh Pallipadi cx->time += idle_time; 968ff69f2bbSalex.shi return idle_time; 9694f86d3a8SLen Brown } 9704f86d3a8SLen Brown 9714f86d3a8SLen Brown struct cpuidle_driver acpi_idle_driver = { 9724f86d3a8SLen Brown .name = "acpi_idle", 9734f86d3a8SLen Brown .owner = THIS_MODULE, 9744f86d3a8SLen Brown }; 9754f86d3a8SLen Brown 9764f86d3a8SLen Brown /** 9774f86d3a8SLen Brown * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE 9784f86d3a8SLen Brown * @pr: the ACPI processor 9794f86d3a8SLen Brown */ 9804f86d3a8SLen Brown static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) 9814f86d3a8SLen Brown { 9829a0b8415Svenkatesh.pallipadi@intel.com int i, count = CPUIDLE_DRIVER_STATE_START; 9834f86d3a8SLen Brown struct acpi_processor_cx *cx; 9844f86d3a8SLen Brown struct cpuidle_state *state; 9854f86d3a8SLen Brown struct cpuidle_device *dev = &pr->power.dev; 9864f86d3a8SLen Brown 9874f86d3a8SLen Brown if (!pr->flags.power_setup_done) 9884f86d3a8SLen Brown return -EINVAL; 9894f86d3a8SLen Brown 9904f86d3a8SLen Brown if (pr->flags.power == 0) { 9914f86d3a8SLen Brown return -EINVAL; 9924f86d3a8SLen Brown } 9934f86d3a8SLen Brown 994dcb84f33SVenkatesh Pallipadi dev->cpu = pr->id; 9954fcb2fcdSVenkatesh Pallipadi for (i = 0; i < CPUIDLE_STATE_MAX; i++) { 9964fcb2fcdSVenkatesh Pallipadi dev->states[i].name[0] = '\0'; 9974fcb2fcdSVenkatesh Pallipadi dev->states[i].desc[0] = '\0'; 9984fcb2fcdSVenkatesh Pallipadi } 9994fcb2fcdSVenkatesh Pallipadi 1000615dfd93SLen Brown if (max_cstate == 0) 1001615dfd93SLen Brown max_cstate = 1; 1002615dfd93SLen Brown 10034f86d3a8SLen Brown for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 10044f86d3a8SLen Brown cx = &pr->power.states[i]; 10054f86d3a8SLen Brown state = &dev->states[count]; 10064f86d3a8SLen Brown 10074f86d3a8SLen Brown if (!cx->valid) 10084f86d3a8SLen Brown continue; 10094f86d3a8SLen Brown 10104f86d3a8SLen Brown #ifdef CONFIG_HOTPLUG_CPU 10114f86d3a8SLen Brown if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && 10124f86d3a8SLen Brown !pr->flags.has_cst && 10134f86d3a8SLen Brown !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 10144f86d3a8SLen Brown continue; 10154f86d3a8SLen Brown #endif 10164f86d3a8SLen Brown cpuidle_set_statedata(state, cx); 10174f86d3a8SLen Brown 10184f86d3a8SLen Brown snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); 10194fcb2fcdSVenkatesh Pallipadi strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); 10204f86d3a8SLen Brown state->exit_latency = cx->latency; 10214963f620SLen Brown state->target_residency = cx->latency * latency_factor; 10224f86d3a8SLen Brown 10234f86d3a8SLen Brown state->flags = 0; 10244f86d3a8SLen Brown switch (cx->type) { 10254f86d3a8SLen Brown case ACPI_STATE_C1: 10268e92b660SVenki Pallipadi if (cx->entry_method == ACPI_CSTATE_FFH) 10279b12e18cSvenkatesh.pallipadi@intel.com state->flags |= CPUIDLE_FLAG_TIME_VALID; 10288e92b660SVenki Pallipadi 10294f86d3a8SLen Brown state->enter = acpi_idle_enter_c1; 1030ddc081a1SVenkatesh Pallipadi dev->safe_state = state; 10314f86d3a8SLen Brown break; 10324f86d3a8SLen Brown 10334f86d3a8SLen Brown case ACPI_STATE_C2: 10344f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_TIME_VALID; 10354f86d3a8SLen Brown state->enter = acpi_idle_enter_simple; 1036ddc081a1SVenkatesh Pallipadi dev->safe_state = state; 10374f86d3a8SLen Brown break; 10384f86d3a8SLen Brown 10394f86d3a8SLen Brown case ACPI_STATE_C3: 10404f86d3a8SLen Brown state->flags |= CPUIDLE_FLAG_TIME_VALID; 10414f86d3a8SLen Brown state->enter = pr->flags.bm_check ? 10424f86d3a8SLen Brown acpi_idle_enter_bm : 10434f86d3a8SLen Brown acpi_idle_enter_simple; 10444f86d3a8SLen Brown break; 10454f86d3a8SLen Brown } 10464f86d3a8SLen Brown 10474f86d3a8SLen Brown count++; 10489a0b8415Svenkatesh.pallipadi@intel.com if (count == CPUIDLE_STATE_MAX) 10499a0b8415Svenkatesh.pallipadi@intel.com break; 10504f86d3a8SLen Brown } 10514f86d3a8SLen Brown 10524f86d3a8SLen Brown dev->state_count = count; 10534f86d3a8SLen Brown 10544f86d3a8SLen Brown if (!count) 10554f86d3a8SLen Brown return -EINVAL; 10564f86d3a8SLen Brown 10574f86d3a8SLen Brown return 0; 10584f86d3a8SLen Brown } 10594f86d3a8SLen Brown 10604f86d3a8SLen Brown int acpi_processor_cst_has_changed(struct acpi_processor *pr) 10614f86d3a8SLen Brown { 1062dcb84f33SVenkatesh Pallipadi int ret = 0; 10634f86d3a8SLen Brown 1064d1896049SThomas Renninger if (disabled_by_idle_boot_param()) 106536a91358SVenkatesh Pallipadi return 0; 106636a91358SVenkatesh Pallipadi 10674f86d3a8SLen Brown if (!pr) 10684f86d3a8SLen Brown return -EINVAL; 10694f86d3a8SLen Brown 10704f86d3a8SLen Brown if (nocst) { 10714f86d3a8SLen Brown return -ENODEV; 10724f86d3a8SLen Brown } 10734f86d3a8SLen Brown 10744f86d3a8SLen Brown if (!pr->flags.power_setup_done) 10754f86d3a8SLen Brown return -ENODEV; 10764f86d3a8SLen Brown 10774f86d3a8SLen Brown cpuidle_pause_and_lock(); 10784f86d3a8SLen Brown cpuidle_disable_device(&pr->power.dev); 10794f86d3a8SLen Brown acpi_processor_get_power_info(pr); 1080dcb84f33SVenkatesh Pallipadi if (pr->flags.power) { 10814f86d3a8SLen Brown acpi_processor_setup_cpuidle(pr); 10824f86d3a8SLen Brown ret = cpuidle_enable_device(&pr->power.dev); 1083dcb84f33SVenkatesh Pallipadi } 10844f86d3a8SLen Brown cpuidle_resume_and_unlock(); 10854f86d3a8SLen Brown 10864f86d3a8SLen Brown return ret; 10874f86d3a8SLen Brown } 10884f86d3a8SLen Brown 10897af8b660SPierre Ossman int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, 10904be44fcdSLen Brown struct acpi_device *device) 10911da177e4SLinus Torvalds { 10921da177e4SLinus Torvalds acpi_status status = 0; 1093b6835052SAndreas Mohr static int first_run; 10941da177e4SLinus Torvalds 1095d1896049SThomas Renninger if (disabled_by_idle_boot_param()) 109636a91358SVenkatesh Pallipadi return 0; 10971da177e4SLinus Torvalds 10981da177e4SLinus Torvalds if (!first_run) { 10991da177e4SLinus Torvalds dmi_check_system(processor_power_dmi_table); 1100c1c30634SAlexey Starikovskiy max_cstate = acpi_processor_cstate_check(max_cstate); 11011da177e4SLinus Torvalds if (max_cstate < ACPI_C_STATES_MAX) 11024be44fcdSLen Brown printk(KERN_NOTICE 11034be44fcdSLen Brown "ACPI: processor limited to max C-state %d\n", 11044be44fcdSLen Brown max_cstate); 11051da177e4SLinus Torvalds first_run++; 11061da177e4SLinus Torvalds } 11071da177e4SLinus Torvalds 110802df8b93SVenkatesh Pallipadi if (!pr) 1109d550d98dSPatrick Mochel return -EINVAL; 111002df8b93SVenkatesh Pallipadi 1111cee324b1SAlexey Starikovskiy if (acpi_gbl_FADT.cst_control && !nocst) { 11124be44fcdSLen Brown status = 1113cee324b1SAlexey Starikovskiy acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8); 11141da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 1115a6fc6720SThomas Renninger ACPI_EXCEPTION((AE_INFO, status, 1116a6fc6720SThomas Renninger "Notifying BIOS of _CST ability failed")); 11171da177e4SLinus Torvalds } 11181da177e4SLinus Torvalds } 11191da177e4SLinus Torvalds 11201da177e4SLinus Torvalds acpi_processor_get_power_info(pr); 11214f86d3a8SLen Brown pr->flags.power_setup_done = 1; 11221da177e4SLinus Torvalds 11231da177e4SLinus Torvalds /* 11241da177e4SLinus Torvalds * Install the idle handler if processor power management is supported. 11251da177e4SLinus Torvalds * Note that we use previously set idle handler will be used on 11261da177e4SLinus Torvalds * platforms that only support C1. 11271da177e4SLinus Torvalds */ 112836a91358SVenkatesh Pallipadi if (pr->flags.power) { 11294f86d3a8SLen Brown acpi_processor_setup_cpuidle(pr); 11304f86d3a8SLen Brown if (cpuidle_register_device(&pr->power.dev)) 11314f86d3a8SLen Brown return -EIO; 11321da177e4SLinus Torvalds } 1133d550d98dSPatrick Mochel return 0; 11341da177e4SLinus Torvalds } 11351da177e4SLinus Torvalds 11364be44fcdSLen Brown int acpi_processor_power_exit(struct acpi_processor *pr, 11374be44fcdSLen Brown struct acpi_device *device) 11381da177e4SLinus Torvalds { 1139d1896049SThomas Renninger if (disabled_by_idle_boot_param()) 114036a91358SVenkatesh Pallipadi return 0; 114136a91358SVenkatesh Pallipadi 11424f86d3a8SLen Brown cpuidle_unregister_device(&pr->power.dev); 11431da177e4SLinus Torvalds pr->flags.power_setup_done = 0; 11441da177e4SLinus Torvalds 1145d550d98dSPatrick Mochel return 0; 11461da177e4SLinus Torvalds } 1147