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> 351da177e4SLinus Torvalds #include <linux/proc_fs.h> 361da177e4SLinus Torvalds #include <linux/seq_file.h> 371da177e4SLinus Torvalds #include <linux/acpi.h> 381da177e4SLinus Torvalds #include <linux/dmi.h> 391da177e4SLinus Torvalds #include <linux/moduleparam.h> 404e57b681STim Schmielau #include <linux/sched.h> /* need_resched() */ 411da177e4SLinus Torvalds 421da177e4SLinus Torvalds #include <asm/io.h> 431da177e4SLinus Torvalds #include <asm/uaccess.h> 441da177e4SLinus Torvalds 451da177e4SLinus Torvalds #include <acpi/acpi_bus.h> 461da177e4SLinus Torvalds #include <acpi/processor.h> 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds #define ACPI_PROCESSOR_COMPONENT 0x01000000 491da177e4SLinus Torvalds #define ACPI_PROCESSOR_CLASS "processor" 501da177e4SLinus Torvalds #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver" 511da177e4SLinus Torvalds #define _COMPONENT ACPI_PROCESSOR_COMPONENT 521da177e4SLinus Torvalds ACPI_MODULE_NAME("acpi_processor") 531da177e4SLinus Torvalds #define ACPI_PROCESSOR_FILE_POWER "power" 541da177e4SLinus Torvalds #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) 551da177e4SLinus Torvalds #define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ 561da177e4SLinus Torvalds #define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ 57b6835052SAndreas Mohr static void (*pm_idle_save) (void) __read_mostly; 581da177e4SLinus Torvalds module_param(max_cstate, uint, 0644); 591da177e4SLinus Torvalds 60b6835052SAndreas Mohr static unsigned int nocst __read_mostly; 611da177e4SLinus Torvalds module_param(nocst, uint, 0000); 621da177e4SLinus Torvalds 631da177e4SLinus Torvalds /* 641da177e4SLinus Torvalds * bm_history -- bit-mask with a bit per jiffy of bus-master activity 651da177e4SLinus Torvalds * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms 661da177e4SLinus Torvalds * 800 HZ: 0xFFFFFFFF: 32 jiffies = 40ms 671da177e4SLinus Torvalds * 100 HZ: 0x0000000F: 4 jiffies = 40ms 681da177e4SLinus Torvalds * reduce history for more aggressive entry into C3 691da177e4SLinus Torvalds */ 70b6835052SAndreas Mohr static unsigned int bm_history __read_mostly = 714be44fcdSLen Brown (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); 721da177e4SLinus Torvalds module_param(bm_history, uint, 0644); 731da177e4SLinus Torvalds /* -------------------------------------------------------------------------- 741da177e4SLinus Torvalds Power Management 751da177e4SLinus Torvalds -------------------------------------------------------------------------- */ 761da177e4SLinus Torvalds 771da177e4SLinus Torvalds /* 781da177e4SLinus Torvalds * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. 791da177e4SLinus Torvalds * For now disable this. Probably a bug somewhere else. 801da177e4SLinus Torvalds * 811da177e4SLinus Torvalds * To skip this limit, boot/load with a large max_cstate limit. 821da177e4SLinus Torvalds */ 83335f16beSDavid Shaohua Li static int set_max_cstate(struct dmi_system_id *id) 841da177e4SLinus Torvalds { 851da177e4SLinus Torvalds if (max_cstate > ACPI_PROCESSOR_MAX_POWER) 861da177e4SLinus Torvalds return 0; 871da177e4SLinus Torvalds 883d35600aSLen Brown printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate." 891da177e4SLinus Torvalds " Override with \"processor.max_cstate=%d\"\n", id->ident, 903d35600aSLen Brown (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); 911da177e4SLinus Torvalds 923d35600aSLen Brown max_cstate = (long)id->driver_data; 931da177e4SLinus Torvalds 941da177e4SLinus Torvalds return 0; 951da177e4SLinus Torvalds } 961da177e4SLinus Torvalds 977ded5689SAshok Raj /* Actually this shouldn't be __cpuinitdata, would be better to fix the 987ded5689SAshok Raj callers to only run once -AK */ 997ded5689SAshok Raj static struct dmi_system_id __cpuinitdata processor_power_dmi_table[] = { 100335f16beSDavid Shaohua Li { set_max_cstate, "IBM ThinkPad R40e", { 101876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 102f831335dSBartlomiej Swiercz DMI_MATCH(DMI_BIOS_VERSION,"1SET70WW")}, (void *)1}, 103f831335dSBartlomiej Swiercz { set_max_cstate, "IBM ThinkPad R40e", { 104f831335dSBartlomiej Swiercz DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 105876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW")}, (void *)1}, 106876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 107876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 108876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET43WW") }, (void*)1}, 109876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 110876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 111876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET45WW") }, (void*)1}, 112876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 113876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 114876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET47WW") }, (void*)1}, 115876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 116876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 117876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET50WW") }, (void*)1}, 118876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 119876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 120876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET52WW") }, (void*)1}, 121876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 122876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 123876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET55WW") }, (void*)1}, 124876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 125876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 126876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET56WW") }, (void*)1}, 127876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 128876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 129876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET59WW") }, (void*)1}, 130876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 131876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 132876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET60WW") }, (void*)1}, 133876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 134876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 135876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET61WW") }, (void*)1}, 136876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 137876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 138876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET62WW") }, (void*)1}, 139876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 140876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 141876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET64WW") }, (void*)1}, 142876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 143876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 144876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET65WW") }, (void*)1}, 145876c184bSThomas Rosner { set_max_cstate, "IBM ThinkPad R40e", { 146876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"IBM"), 147876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"1SET68WW") }, (void*)1}, 148335f16beSDavid Shaohua Li { set_max_cstate, "Medion 41700", { 149876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), 150876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"R01-A1J")}, (void *)1}, 151335f16beSDavid Shaohua Li { set_max_cstate, "Clevo 5600D", { 152876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), 153876c184bSThomas Rosner DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, 154335f16beSDavid Shaohua Li (void *)2}, 1551da177e4SLinus Torvalds {}, 1561da177e4SLinus Torvalds }; 1571da177e4SLinus Torvalds 1584be44fcdSLen Brown static inline u32 ticks_elapsed(u32 t1, u32 t2) 1591da177e4SLinus Torvalds { 1601da177e4SLinus Torvalds if (t2 >= t1) 1611da177e4SLinus Torvalds return (t2 - t1); 1621da177e4SLinus Torvalds else if (!acpi_fadt.tmr_val_ext) 1631da177e4SLinus Torvalds return (((0x00FFFFFF - t1) + t2) & 0x00FFFFFF); 1641da177e4SLinus Torvalds else 1651da177e4SLinus Torvalds return ((0xFFFFFFFF - t1) + t2); 1661da177e4SLinus Torvalds } 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds static void 1694be44fcdSLen Brown acpi_processor_power_activate(struct acpi_processor *pr, 1701da177e4SLinus Torvalds struct acpi_processor_cx *new) 1711da177e4SLinus Torvalds { 1721da177e4SLinus Torvalds struct acpi_processor_cx *old; 1731da177e4SLinus Torvalds 1741da177e4SLinus Torvalds if (!pr || !new) 1751da177e4SLinus Torvalds return; 1761da177e4SLinus Torvalds 1771da177e4SLinus Torvalds old = pr->power.state; 1781da177e4SLinus Torvalds 1791da177e4SLinus Torvalds if (old) 1801da177e4SLinus Torvalds old->promotion.count = 0; 1811da177e4SLinus Torvalds new->demotion.count = 0; 1821da177e4SLinus Torvalds 1831da177e4SLinus Torvalds /* Cleanup from old state. */ 1841da177e4SLinus Torvalds if (old) { 1851da177e4SLinus Torvalds switch (old->type) { 1861da177e4SLinus Torvalds case ACPI_STATE_C3: 1871da177e4SLinus Torvalds /* Disable bus master reload */ 18802df8b93SVenkatesh Pallipadi if (new->type != ACPI_STATE_C3 && pr->flags.bm_check) 1894be44fcdSLen Brown acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0, 1904be44fcdSLen Brown ACPI_MTX_DO_NOT_LOCK); 1911da177e4SLinus Torvalds break; 1921da177e4SLinus Torvalds } 1931da177e4SLinus Torvalds } 1941da177e4SLinus Torvalds 1951da177e4SLinus Torvalds /* Prepare to use new state. */ 1961da177e4SLinus Torvalds switch (new->type) { 1971da177e4SLinus Torvalds case ACPI_STATE_C3: 1981da177e4SLinus Torvalds /* Enable bus master reload */ 19902df8b93SVenkatesh Pallipadi if (old->type != ACPI_STATE_C3 && pr->flags.bm_check) 2004be44fcdSLen Brown acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1, 2014be44fcdSLen Brown ACPI_MTX_DO_NOT_LOCK); 2021da177e4SLinus Torvalds break; 2031da177e4SLinus Torvalds } 2041da177e4SLinus Torvalds 2051da177e4SLinus Torvalds pr->power.state = new; 2061da177e4SLinus Torvalds 2071da177e4SLinus Torvalds return; 2081da177e4SLinus Torvalds } 2091da177e4SLinus Torvalds 21064c7c8f8SNick Piggin static void acpi_safe_halt(void) 21164c7c8f8SNick Piggin { 212495ab9c0SAndi Kleen current_thread_info()->status &= ~TS_POLLING; 21364c7c8f8SNick Piggin smp_mb__after_clear_bit(); 21464c7c8f8SNick Piggin if (!need_resched()) 21564c7c8f8SNick Piggin safe_halt(); 216495ab9c0SAndi Kleen current_thread_info()->status |= TS_POLLING; 21764c7c8f8SNick Piggin } 21864c7c8f8SNick Piggin 21902df8b93SVenkatesh Pallipadi static atomic_t c3_cpu_count; 22002df8b93SVenkatesh Pallipadi 2211da177e4SLinus Torvalds static void acpi_processor_idle(void) 2221da177e4SLinus Torvalds { 2231da177e4SLinus Torvalds struct acpi_processor *pr = NULL; 2241da177e4SLinus Torvalds struct acpi_processor_cx *cx = NULL; 2251da177e4SLinus Torvalds struct acpi_processor_cx *next_state = NULL; 2261da177e4SLinus Torvalds int sleep_ticks = 0; 2271da177e4SLinus Torvalds u32 t1, t2 = 0; 2281da177e4SLinus Torvalds 22964c7c8f8SNick Piggin pr = processors[smp_processor_id()]; 2301da177e4SLinus Torvalds if (!pr) 2311da177e4SLinus Torvalds return; 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds /* 2341da177e4SLinus Torvalds * Interrupts must be disabled during bus mastering calculations and 2351da177e4SLinus Torvalds * for C2/C3 transitions. 2361da177e4SLinus Torvalds */ 2371da177e4SLinus Torvalds local_irq_disable(); 2381da177e4SLinus Torvalds 2391da177e4SLinus Torvalds /* 2401da177e4SLinus Torvalds * Check whether we truly need to go idle, or should 2411da177e4SLinus Torvalds * reschedule: 2421da177e4SLinus Torvalds */ 2431da177e4SLinus Torvalds if (unlikely(need_resched())) { 2441da177e4SLinus Torvalds local_irq_enable(); 2451da177e4SLinus Torvalds return; 2461da177e4SLinus Torvalds } 2471da177e4SLinus Torvalds 2481da177e4SLinus Torvalds cx = pr->power.state; 24964c7c8f8SNick Piggin if (!cx) { 25064c7c8f8SNick Piggin if (pm_idle_save) 25164c7c8f8SNick Piggin pm_idle_save(); 25264c7c8f8SNick Piggin else 25364c7c8f8SNick Piggin acpi_safe_halt(); 25464c7c8f8SNick Piggin return; 25564c7c8f8SNick Piggin } 2561da177e4SLinus Torvalds 2571da177e4SLinus Torvalds /* 2581da177e4SLinus Torvalds * Check BM Activity 2591da177e4SLinus Torvalds * ----------------- 2601da177e4SLinus Torvalds * Check for bus mastering activity (if required), record, and check 2611da177e4SLinus Torvalds * for demotion. 2621da177e4SLinus Torvalds */ 2631da177e4SLinus Torvalds if (pr->flags.bm_check) { 2641da177e4SLinus Torvalds u32 bm_status = 0; 2651da177e4SLinus Torvalds unsigned long diff = jiffies - pr->power.bm_check_timestamp; 2661da177e4SLinus Torvalds 267c5ab81caSDominik Brodowski if (diff > 31) 268c5ab81caSDominik Brodowski diff = 31; 2691da177e4SLinus Torvalds 270c5ab81caSDominik Brodowski pr->power.bm_activity <<= diff; 2711da177e4SLinus Torvalds 2721da177e4SLinus Torvalds acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, 2731da177e4SLinus Torvalds &bm_status, ACPI_MTX_DO_NOT_LOCK); 2741da177e4SLinus Torvalds if (bm_status) { 275c5ab81caSDominik Brodowski pr->power.bm_activity |= 0x1; 2761da177e4SLinus Torvalds acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 2771da177e4SLinus Torvalds 1, ACPI_MTX_DO_NOT_LOCK); 2781da177e4SLinus Torvalds } 2791da177e4SLinus Torvalds /* 2801da177e4SLinus Torvalds * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect 2811da177e4SLinus Torvalds * the true state of bus mastering activity; forcing us to 2821da177e4SLinus Torvalds * manually check the BMIDEA bit of each IDE channel. 2831da177e4SLinus Torvalds */ 2841da177e4SLinus Torvalds else if (errata.piix4.bmisx) { 2851da177e4SLinus Torvalds if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) 2861da177e4SLinus Torvalds || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) 287c5ab81caSDominik Brodowski pr->power.bm_activity |= 0x1; 2881da177e4SLinus Torvalds } 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds pr->power.bm_check_timestamp = jiffies; 2911da177e4SLinus Torvalds 2921da177e4SLinus Torvalds /* 293c4a001b1SDominik Brodowski * If bus mastering is or was active this jiffy, demote 2941da177e4SLinus Torvalds * to avoid a faulty transition. Note that the processor 2951da177e4SLinus Torvalds * won't enter a low-power state during this call (to this 296c4a001b1SDominik Brodowski * function) but should upon the next. 2971da177e4SLinus Torvalds * 2981da177e4SLinus Torvalds * TBD: A better policy might be to fallback to the demotion 2991da177e4SLinus Torvalds * state (use it for this quantum only) istead of 3001da177e4SLinus Torvalds * demoting -- and rely on duration as our sole demotion 3011da177e4SLinus Torvalds * qualification. This may, however, introduce DMA 3021da177e4SLinus Torvalds * issues (e.g. floppy DMA transfer overrun/underrun). 3031da177e4SLinus Torvalds */ 304c4a001b1SDominik Brodowski if ((pr->power.bm_activity & 0x1) && 305c4a001b1SDominik Brodowski cx->demotion.threshold.bm) { 3061da177e4SLinus Torvalds local_irq_enable(); 3071da177e4SLinus Torvalds next_state = cx->demotion.state; 3081da177e4SLinus Torvalds goto end; 3091da177e4SLinus Torvalds } 3101da177e4SLinus Torvalds } 3111da177e4SLinus Torvalds 3124c033552SVenkatesh Pallipadi #ifdef CONFIG_HOTPLUG_CPU 3134c033552SVenkatesh Pallipadi /* 3144c033552SVenkatesh Pallipadi * Check for P_LVL2_UP flag before entering C2 and above on 3154c033552SVenkatesh Pallipadi * an SMP system. We do it here instead of doing it at _CST/P_LVL 3164c033552SVenkatesh Pallipadi * detection phase, to work cleanly with logical CPU hotplug. 3174c033552SVenkatesh Pallipadi */ 3184c033552SVenkatesh Pallipadi if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && 3191e483969SDavid Shaohua Li !pr->flags.has_cst && !acpi_fadt.plvl2_up) 3201e483969SDavid Shaohua Li cx = &pr->power.states[ACPI_STATE_C1]; 3214c033552SVenkatesh Pallipadi #endif 3221e483969SDavid Shaohua Li 3231da177e4SLinus Torvalds /* 3241da177e4SLinus Torvalds * Sleep: 3251da177e4SLinus Torvalds * ------ 3261da177e4SLinus Torvalds * Invoke the current Cx state to put the processor to sleep. 3271da177e4SLinus Torvalds */ 3282a298a35SNick Piggin if (cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) { 329495ab9c0SAndi Kleen current_thread_info()->status &= ~TS_POLLING; 3302a298a35SNick Piggin smp_mb__after_clear_bit(); 3312a298a35SNick Piggin if (need_resched()) { 332495ab9c0SAndi Kleen current_thread_info()->status |= TS_POLLING; 333af2eb17bSLinus Torvalds local_irq_enable(); 3342a298a35SNick Piggin return; 3352a298a35SNick Piggin } 3362a298a35SNick Piggin } 3372a298a35SNick Piggin 3381da177e4SLinus Torvalds switch (cx->type) { 3391da177e4SLinus Torvalds 3401da177e4SLinus Torvalds case ACPI_STATE_C1: 3411da177e4SLinus Torvalds /* 3421da177e4SLinus Torvalds * Invoke C1. 3431da177e4SLinus Torvalds * Use the appropriate idle routine, the one that would 3441da177e4SLinus Torvalds * be used without acpi C-states. 3451da177e4SLinus Torvalds */ 3461da177e4SLinus Torvalds if (pm_idle_save) 3471da177e4SLinus Torvalds pm_idle_save(); 3481da177e4SLinus Torvalds else 34964c7c8f8SNick Piggin acpi_safe_halt(); 35064c7c8f8SNick Piggin 3511da177e4SLinus Torvalds /* 3521da177e4SLinus Torvalds * TBD: Can't get time duration while in C1, as resumes 3531da177e4SLinus Torvalds * go to an ISR rather than here. Need to instrument 3541da177e4SLinus Torvalds * base interrupt handler. 3551da177e4SLinus Torvalds */ 3561da177e4SLinus Torvalds sleep_ticks = 0xFFFFFFFF; 3571da177e4SLinus Torvalds break; 3581da177e4SLinus Torvalds 3591da177e4SLinus Torvalds case ACPI_STATE_C2: 3601da177e4SLinus Torvalds /* Get start time (ticks) */ 3611da177e4SLinus Torvalds t1 = inl(acpi_fadt.xpm_tmr_blk.address); 3621da177e4SLinus Torvalds /* Invoke C2 */ 3631da177e4SLinus Torvalds inb(cx->address); 364b488f021SAndreas Mohr /* Dummy wait op - must do something useless after P_LVL2 read 365b488f021SAndreas Mohr because chipsets cannot guarantee that STPCLK# signal 366b488f021SAndreas Mohr gets asserted in time to freeze execution properly. */ 3671da177e4SLinus Torvalds t2 = inl(acpi_fadt.xpm_tmr_blk.address); 3681da177e4SLinus Torvalds /* Get end time (ticks) */ 3691da177e4SLinus Torvalds t2 = inl(acpi_fadt.xpm_tmr_blk.address); 370539eb11eSjohn stultz 371539eb11eSjohn stultz #ifdef CONFIG_GENERIC_TIME 372539eb11eSjohn stultz /* TSC halts in C2, so notify users */ 373539eb11eSjohn stultz mark_tsc_unstable(); 374539eb11eSjohn stultz #endif 3751da177e4SLinus Torvalds /* Re-enable interrupts */ 3761da177e4SLinus Torvalds local_irq_enable(); 377495ab9c0SAndi Kleen current_thread_info()->status |= TS_POLLING; 3781da177e4SLinus Torvalds /* Compute time (ticks) that we were actually asleep */ 3794be44fcdSLen Brown sleep_ticks = 3804be44fcdSLen Brown ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD; 3811da177e4SLinus Torvalds break; 3821da177e4SLinus Torvalds 3831da177e4SLinus Torvalds case ACPI_STATE_C3: 38402df8b93SVenkatesh Pallipadi 38502df8b93SVenkatesh Pallipadi if (pr->flags.bm_check) { 38602df8b93SVenkatesh Pallipadi if (atomic_inc_return(&c3_cpu_count) == 38702df8b93SVenkatesh Pallipadi num_online_cpus()) { 38802df8b93SVenkatesh Pallipadi /* 38902df8b93SVenkatesh Pallipadi * All CPUs are trying to go to C3 39002df8b93SVenkatesh Pallipadi * Disable bus master arbitration 39102df8b93SVenkatesh Pallipadi */ 39202df8b93SVenkatesh Pallipadi acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1, 39302df8b93SVenkatesh Pallipadi ACPI_MTX_DO_NOT_LOCK); 39402df8b93SVenkatesh Pallipadi } 39502df8b93SVenkatesh Pallipadi } else { 39602df8b93SVenkatesh Pallipadi /* SMP with no shared cache... Invalidate cache */ 39702df8b93SVenkatesh Pallipadi ACPI_FLUSH_CPU_CACHE(); 39802df8b93SVenkatesh Pallipadi } 39902df8b93SVenkatesh Pallipadi 4001da177e4SLinus Torvalds /* Get start time (ticks) */ 4011da177e4SLinus Torvalds t1 = inl(acpi_fadt.xpm_tmr_blk.address); 4021da177e4SLinus Torvalds /* Invoke C3 */ 4031da177e4SLinus Torvalds inb(cx->address); 404b488f021SAndreas Mohr /* Dummy wait op (see above) */ 4051da177e4SLinus Torvalds t2 = inl(acpi_fadt.xpm_tmr_blk.address); 4061da177e4SLinus Torvalds /* Get end time (ticks) */ 4071da177e4SLinus Torvalds t2 = inl(acpi_fadt.xpm_tmr_blk.address); 40802df8b93SVenkatesh Pallipadi if (pr->flags.bm_check) { 4091da177e4SLinus Torvalds /* Enable bus master arbitration */ 41002df8b93SVenkatesh Pallipadi atomic_dec(&c3_cpu_count); 4114be44fcdSLen Brown acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0, 4124be44fcdSLen Brown ACPI_MTX_DO_NOT_LOCK); 41302df8b93SVenkatesh Pallipadi } 41402df8b93SVenkatesh Pallipadi 415539eb11eSjohn stultz #ifdef CONFIG_GENERIC_TIME 416539eb11eSjohn stultz /* TSC halts in C3, so notify users */ 417539eb11eSjohn stultz mark_tsc_unstable(); 418539eb11eSjohn stultz #endif 4191da177e4SLinus Torvalds /* Re-enable interrupts */ 4201da177e4SLinus Torvalds local_irq_enable(); 421495ab9c0SAndi Kleen current_thread_info()->status |= TS_POLLING; 4221da177e4SLinus Torvalds /* Compute time (ticks) that we were actually asleep */ 4234be44fcdSLen Brown sleep_ticks = 4244be44fcdSLen Brown ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD; 4251da177e4SLinus Torvalds break; 4261da177e4SLinus Torvalds 4271da177e4SLinus Torvalds default: 4281da177e4SLinus Torvalds local_irq_enable(); 4291da177e4SLinus Torvalds return; 4301da177e4SLinus Torvalds } 431a3c6598fSDominik Brodowski cx->usage++; 432a3c6598fSDominik Brodowski if ((cx->type != ACPI_STATE_C1) && (sleep_ticks > 0)) 433a3c6598fSDominik Brodowski cx->time += sleep_ticks; 4341da177e4SLinus Torvalds 4351da177e4SLinus Torvalds next_state = pr->power.state; 4361da177e4SLinus Torvalds 4371e483969SDavid Shaohua Li #ifdef CONFIG_HOTPLUG_CPU 4381e483969SDavid Shaohua Li /* Don't do promotion/demotion */ 4391e483969SDavid Shaohua Li if ((cx->type == ACPI_STATE_C1) && (num_online_cpus() > 1) && 4401e483969SDavid Shaohua Li !pr->flags.has_cst && !acpi_fadt.plvl2_up) { 4411e483969SDavid Shaohua Li next_state = cx; 4421e483969SDavid Shaohua Li goto end; 4431e483969SDavid Shaohua Li } 4441e483969SDavid Shaohua Li #endif 4451e483969SDavid Shaohua Li 4461da177e4SLinus Torvalds /* 4471da177e4SLinus Torvalds * Promotion? 4481da177e4SLinus Torvalds * ---------- 4491da177e4SLinus Torvalds * Track the number of longs (time asleep is greater than threshold) 4501da177e4SLinus Torvalds * and promote when the count threshold is reached. Note that bus 4511da177e4SLinus Torvalds * mastering activity may prevent promotions. 4521da177e4SLinus Torvalds * Do not promote above max_cstate. 4531da177e4SLinus Torvalds */ 4541da177e4SLinus Torvalds if (cx->promotion.state && 4551da177e4SLinus Torvalds ((cx->promotion.state - pr->power.states) <= max_cstate)) { 4561da177e4SLinus Torvalds if (sleep_ticks > cx->promotion.threshold.ticks) { 4571da177e4SLinus Torvalds cx->promotion.count++; 4581da177e4SLinus Torvalds cx->demotion.count = 0; 4594be44fcdSLen Brown if (cx->promotion.count >= 4604be44fcdSLen Brown cx->promotion.threshold.count) { 4611da177e4SLinus Torvalds if (pr->flags.bm_check) { 4624be44fcdSLen Brown if (! 4634be44fcdSLen Brown (pr->power.bm_activity & cx-> 4644be44fcdSLen Brown promotion.threshold.bm)) { 4654be44fcdSLen Brown next_state = 4664be44fcdSLen Brown cx->promotion.state; 4671da177e4SLinus Torvalds goto end; 4681da177e4SLinus Torvalds } 4694be44fcdSLen Brown } else { 4701da177e4SLinus Torvalds next_state = cx->promotion.state; 4711da177e4SLinus Torvalds goto end; 4721da177e4SLinus Torvalds } 4731da177e4SLinus Torvalds } 4741da177e4SLinus Torvalds } 4751da177e4SLinus Torvalds } 4761da177e4SLinus Torvalds 4771da177e4SLinus Torvalds /* 4781da177e4SLinus Torvalds * Demotion? 4791da177e4SLinus Torvalds * --------- 4801da177e4SLinus Torvalds * Track the number of shorts (time asleep is less than time threshold) 4811da177e4SLinus Torvalds * and demote when the usage threshold is reached. 4821da177e4SLinus Torvalds */ 4831da177e4SLinus Torvalds if (cx->demotion.state) { 4841da177e4SLinus Torvalds if (sleep_ticks < cx->demotion.threshold.ticks) { 4851da177e4SLinus Torvalds cx->demotion.count++; 4861da177e4SLinus Torvalds cx->promotion.count = 0; 4871da177e4SLinus Torvalds if (cx->demotion.count >= cx->demotion.threshold.count) { 4881da177e4SLinus Torvalds next_state = cx->demotion.state; 4891da177e4SLinus Torvalds goto end; 4901da177e4SLinus Torvalds } 4911da177e4SLinus Torvalds } 4921da177e4SLinus Torvalds } 4931da177e4SLinus Torvalds 4941da177e4SLinus Torvalds end: 4951da177e4SLinus Torvalds /* 4961da177e4SLinus Torvalds * Demote if current state exceeds max_cstate 4971da177e4SLinus Torvalds */ 4981da177e4SLinus Torvalds if ((pr->power.state - pr->power.states) > max_cstate) { 4991da177e4SLinus Torvalds if (cx->demotion.state) 5001da177e4SLinus Torvalds next_state = cx->demotion.state; 5011da177e4SLinus Torvalds } 5021da177e4SLinus Torvalds 5031da177e4SLinus Torvalds /* 5041da177e4SLinus Torvalds * New Cx State? 5051da177e4SLinus Torvalds * ------------- 5061da177e4SLinus Torvalds * If we're going to start using a new Cx state we must clean up 5071da177e4SLinus Torvalds * from the previous and prepare to use the new. 5081da177e4SLinus Torvalds */ 5091da177e4SLinus Torvalds if (next_state != pr->power.state) 5101da177e4SLinus Torvalds acpi_processor_power_activate(pr, next_state); 5111da177e4SLinus Torvalds } 5121da177e4SLinus Torvalds 5134be44fcdSLen Brown static int acpi_processor_set_power_policy(struct acpi_processor *pr) 5141da177e4SLinus Torvalds { 5151da177e4SLinus Torvalds unsigned int i; 5161da177e4SLinus Torvalds unsigned int state_is_set = 0; 5171da177e4SLinus Torvalds struct acpi_processor_cx *lower = NULL; 5181da177e4SLinus Torvalds struct acpi_processor_cx *higher = NULL; 5191da177e4SLinus Torvalds struct acpi_processor_cx *cx; 5201da177e4SLinus Torvalds 5211da177e4SLinus Torvalds 5221da177e4SLinus Torvalds if (!pr) 523d550d98dSPatrick Mochel return -EINVAL; 5241da177e4SLinus Torvalds 5251da177e4SLinus Torvalds /* 5261da177e4SLinus Torvalds * This function sets the default Cx state policy (OS idle handler). 5271da177e4SLinus Torvalds * Our scheme is to promote quickly to C2 but more conservatively 5281da177e4SLinus Torvalds * to C3. We're favoring C2 for its characteristics of low latency 5291da177e4SLinus Torvalds * (quick response), good power savings, and ability to allow bus 5301da177e4SLinus Torvalds * mastering activity. Note that the Cx state policy is completely 5311da177e4SLinus Torvalds * customizable and can be altered dynamically. 5321da177e4SLinus Torvalds */ 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds /* startup state */ 5351da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 5361da177e4SLinus Torvalds cx = &pr->power.states[i]; 5371da177e4SLinus Torvalds if (!cx->valid) 5381da177e4SLinus Torvalds continue; 5391da177e4SLinus Torvalds 5401da177e4SLinus Torvalds if (!state_is_set) 5411da177e4SLinus Torvalds pr->power.state = cx; 5421da177e4SLinus Torvalds state_is_set++; 5431da177e4SLinus Torvalds break; 5441da177e4SLinus Torvalds } 5451da177e4SLinus Torvalds 5461da177e4SLinus Torvalds if (!state_is_set) 547d550d98dSPatrick Mochel return -ENODEV; 5481da177e4SLinus Torvalds 5491da177e4SLinus Torvalds /* demotion */ 5501da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 5511da177e4SLinus Torvalds cx = &pr->power.states[i]; 5521da177e4SLinus Torvalds if (!cx->valid) 5531da177e4SLinus Torvalds continue; 5541da177e4SLinus Torvalds 5551da177e4SLinus Torvalds if (lower) { 5561da177e4SLinus Torvalds cx->demotion.state = lower; 5571da177e4SLinus Torvalds cx->demotion.threshold.ticks = cx->latency_ticks; 5581da177e4SLinus Torvalds cx->demotion.threshold.count = 1; 5591da177e4SLinus Torvalds if (cx->type == ACPI_STATE_C3) 5601da177e4SLinus Torvalds cx->demotion.threshold.bm = bm_history; 5611da177e4SLinus Torvalds } 5621da177e4SLinus Torvalds 5631da177e4SLinus Torvalds lower = cx; 5641da177e4SLinus Torvalds } 5651da177e4SLinus Torvalds 5661da177e4SLinus Torvalds /* promotion */ 5671da177e4SLinus Torvalds for (i = (ACPI_PROCESSOR_MAX_POWER - 1); i > 0; i--) { 5681da177e4SLinus Torvalds cx = &pr->power.states[i]; 5691da177e4SLinus Torvalds if (!cx->valid) 5701da177e4SLinus Torvalds continue; 5711da177e4SLinus Torvalds 5721da177e4SLinus Torvalds if (higher) { 5731da177e4SLinus Torvalds cx->promotion.state = higher; 5741da177e4SLinus Torvalds cx->promotion.threshold.ticks = cx->latency_ticks; 5751da177e4SLinus Torvalds if (cx->type >= ACPI_STATE_C2) 5761da177e4SLinus Torvalds cx->promotion.threshold.count = 4; 5771da177e4SLinus Torvalds else 5781da177e4SLinus Torvalds cx->promotion.threshold.count = 10; 5791da177e4SLinus Torvalds if (higher->type == ACPI_STATE_C3) 5801da177e4SLinus Torvalds cx->promotion.threshold.bm = bm_history; 5811da177e4SLinus Torvalds } 5821da177e4SLinus Torvalds 5831da177e4SLinus Torvalds higher = cx; 5841da177e4SLinus Torvalds } 5851da177e4SLinus Torvalds 586d550d98dSPatrick Mochel return 0; 5871da177e4SLinus Torvalds } 5881da177e4SLinus Torvalds 5891da177e4SLinus Torvalds static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 5901da177e4SLinus Torvalds { 5911da177e4SLinus Torvalds 5921da177e4SLinus Torvalds if (!pr) 593d550d98dSPatrick Mochel return -EINVAL; 5941da177e4SLinus Torvalds 5951da177e4SLinus Torvalds if (!pr->pblk) 596d550d98dSPatrick Mochel return -ENODEV; 5971da177e4SLinus Torvalds 5981da177e4SLinus Torvalds /* if info is obtained from pblk/fadt, type equals state */ 5991da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; 6001da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; 6011da177e4SLinus Torvalds 6024c033552SVenkatesh Pallipadi #ifndef CONFIG_HOTPLUG_CPU 6034c033552SVenkatesh Pallipadi /* 6044c033552SVenkatesh Pallipadi * Check for P_LVL2_UP flag before entering C2 and above on 6054c033552SVenkatesh Pallipadi * an SMP system. 6064c033552SVenkatesh Pallipadi */ 6071e483969SDavid Shaohua Li if ((num_online_cpus() > 1) && !acpi_fadt.plvl2_up) 608d550d98dSPatrick Mochel return -ENODEV; 6094c033552SVenkatesh Pallipadi #endif 6104c033552SVenkatesh Pallipadi 6111da177e4SLinus Torvalds /* determine C2 and C3 address from pblk */ 6121da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; 6131da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; 6141da177e4SLinus Torvalds 6151da177e4SLinus Torvalds /* determine latencies from FADT */ 6161da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].latency = acpi_fadt.plvl2_lat; 6171da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].latency = acpi_fadt.plvl3_lat; 6181da177e4SLinus Torvalds 6191da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 6201da177e4SLinus Torvalds "lvl2[0x%08x] lvl3[0x%08x]\n", 6211da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C2].address, 6221da177e4SLinus Torvalds pr->power.states[ACPI_STATE_C3].address)); 6231da177e4SLinus Torvalds 624d550d98dSPatrick Mochel return 0; 6251da177e4SLinus Torvalds } 6261da177e4SLinus Torvalds 627acf05f4bSVenkatesh Pallipadi static int acpi_processor_get_power_info_default_c1(struct acpi_processor *pr) 628acf05f4bSVenkatesh Pallipadi { 629acf05f4bSVenkatesh Pallipadi 630cf824788SJanosch Machowinski /* Zero initialize all the C-states info. */ 6312203d6edSLinus Torvalds memset(pr->power.states, 0, sizeof(pr->power.states)); 632acf05f4bSVenkatesh Pallipadi 633cf824788SJanosch Machowinski /* set the first C-State to C1 */ 634acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; 635acf05f4bSVenkatesh Pallipadi 636acf05f4bSVenkatesh Pallipadi /* the C0 state only exists as a filler in our array, 637acf05f4bSVenkatesh Pallipadi * and all processors need to support C1 */ 638acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C0].valid = 1; 639acf05f4bSVenkatesh Pallipadi pr->power.states[ACPI_STATE_C1].valid = 1; 640acf05f4bSVenkatesh Pallipadi 641d550d98dSPatrick Mochel return 0; 642acf05f4bSVenkatesh Pallipadi } 643acf05f4bSVenkatesh Pallipadi 6441da177e4SLinus Torvalds static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) 6451da177e4SLinus Torvalds { 6461da177e4SLinus Torvalds acpi_status status = 0; 6471da177e4SLinus Torvalds acpi_integer count; 648cf824788SJanosch Machowinski int current_count; 6491da177e4SLinus Torvalds int i; 6501da177e4SLinus Torvalds struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 6511da177e4SLinus Torvalds union acpi_object *cst; 6521da177e4SLinus Torvalds 6531da177e4SLinus Torvalds 6541da177e4SLinus Torvalds if (nocst) 655d550d98dSPatrick Mochel return -ENODEV; 6561da177e4SLinus Torvalds 657cf824788SJanosch Machowinski current_count = 1; 658cf824788SJanosch Machowinski 659cf824788SJanosch Machowinski /* Zero initialize C2 onwards and prepare for fresh CST lookup */ 660cf824788SJanosch Machowinski for (i = 2; i < ACPI_PROCESSOR_MAX_POWER; i++) 6610b6b2f08SVenkatesh Pallipadi memset(&(pr->power.states[i]), 0, 6620b6b2f08SVenkatesh Pallipadi sizeof(struct acpi_processor_cx)); 6631da177e4SLinus Torvalds 6641da177e4SLinus Torvalds status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer); 6651da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 6661da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n")); 667d550d98dSPatrick Mochel return -ENODEV; 6681da177e4SLinus Torvalds } 6691da177e4SLinus Torvalds 6701da177e4SLinus Torvalds cst = (union acpi_object *)buffer.pointer; 6711da177e4SLinus Torvalds 6721da177e4SLinus Torvalds /* There must be at least 2 elements */ 6731da177e4SLinus Torvalds if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) { 6746468463aSLen Brown printk(KERN_ERR PREFIX "not enough elements in _CST\n"); 6751da177e4SLinus Torvalds status = -EFAULT; 6761da177e4SLinus Torvalds goto end; 6771da177e4SLinus Torvalds } 6781da177e4SLinus Torvalds 6791da177e4SLinus Torvalds count = cst->package.elements[0].integer.value; 6801da177e4SLinus Torvalds 6811da177e4SLinus Torvalds /* Validate number of power states. */ 6821da177e4SLinus Torvalds if (count < 1 || count != cst->package.count - 1) { 6836468463aSLen Brown printk(KERN_ERR PREFIX "count given by _CST is not valid\n"); 6841da177e4SLinus Torvalds status = -EFAULT; 6851da177e4SLinus Torvalds goto end; 6861da177e4SLinus Torvalds } 6871da177e4SLinus Torvalds 6881da177e4SLinus Torvalds /* Tell driver that at least _CST is supported. */ 6891da177e4SLinus Torvalds pr->flags.has_cst = 1; 6901da177e4SLinus Torvalds 6911da177e4SLinus Torvalds for (i = 1; i <= count; i++) { 6921da177e4SLinus Torvalds union acpi_object *element; 6931da177e4SLinus Torvalds union acpi_object *obj; 6941da177e4SLinus Torvalds struct acpi_power_register *reg; 6951da177e4SLinus Torvalds struct acpi_processor_cx cx; 6961da177e4SLinus Torvalds 6971da177e4SLinus Torvalds memset(&cx, 0, sizeof(cx)); 6981da177e4SLinus Torvalds 6991da177e4SLinus Torvalds element = (union acpi_object *)&(cst->package.elements[i]); 7001da177e4SLinus Torvalds if (element->type != ACPI_TYPE_PACKAGE) 7011da177e4SLinus Torvalds continue; 7021da177e4SLinus Torvalds 7031da177e4SLinus Torvalds if (element->package.count != 4) 7041da177e4SLinus Torvalds continue; 7051da177e4SLinus Torvalds 7061da177e4SLinus Torvalds obj = (union acpi_object *)&(element->package.elements[0]); 7071da177e4SLinus Torvalds 7081da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_BUFFER) 7091da177e4SLinus Torvalds continue; 7101da177e4SLinus Torvalds 7111da177e4SLinus Torvalds reg = (struct acpi_power_register *)obj->buffer.pointer; 7121da177e4SLinus Torvalds 7131da177e4SLinus Torvalds if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && 7141da177e4SLinus Torvalds (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) 7151da177e4SLinus Torvalds continue; 7161da177e4SLinus Torvalds 7171da177e4SLinus Torvalds cx.address = (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) ? 7181da177e4SLinus Torvalds 0 : reg->address; 7191da177e4SLinus Torvalds 7201da177e4SLinus Torvalds /* There should be an easy way to extract an integer... */ 7211da177e4SLinus Torvalds obj = (union acpi_object *)&(element->package.elements[1]); 7221da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 7231da177e4SLinus Torvalds continue; 7241da177e4SLinus Torvalds 7251da177e4SLinus Torvalds cx.type = obj->integer.value; 7261da177e4SLinus Torvalds 7271da177e4SLinus Torvalds if ((cx.type != ACPI_STATE_C1) && 7281da177e4SLinus Torvalds (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) 7291da177e4SLinus Torvalds continue; 7301da177e4SLinus Torvalds 731cf824788SJanosch Machowinski if ((cx.type < ACPI_STATE_C2) || (cx.type > ACPI_STATE_C3)) 7321da177e4SLinus Torvalds continue; 7331da177e4SLinus Torvalds 7341da177e4SLinus Torvalds obj = (union acpi_object *)&(element->package.elements[2]); 7351da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 7361da177e4SLinus Torvalds continue; 7371da177e4SLinus Torvalds 7381da177e4SLinus Torvalds cx.latency = obj->integer.value; 7391da177e4SLinus Torvalds 7401da177e4SLinus Torvalds obj = (union acpi_object *)&(element->package.elements[3]); 7411da177e4SLinus Torvalds if (obj->type != ACPI_TYPE_INTEGER) 7421da177e4SLinus Torvalds continue; 7431da177e4SLinus Torvalds 7441da177e4SLinus Torvalds cx.power = obj->integer.value; 7451da177e4SLinus Torvalds 746cf824788SJanosch Machowinski current_count++; 747cf824788SJanosch Machowinski memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx)); 748cf824788SJanosch Machowinski 749cf824788SJanosch Machowinski /* 750cf824788SJanosch Machowinski * We support total ACPI_PROCESSOR_MAX_POWER - 1 751cf824788SJanosch Machowinski * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1) 752cf824788SJanosch Machowinski */ 753cf824788SJanosch Machowinski if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) { 754cf824788SJanosch Machowinski printk(KERN_WARNING 755cf824788SJanosch Machowinski "Limiting number of power states to max (%d)\n", 756cf824788SJanosch Machowinski ACPI_PROCESSOR_MAX_POWER); 757cf824788SJanosch Machowinski printk(KERN_WARNING 758cf824788SJanosch Machowinski "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); 759cf824788SJanosch Machowinski break; 760cf824788SJanosch Machowinski } 7611da177e4SLinus Torvalds } 7621da177e4SLinus Torvalds 7634be44fcdSLen Brown ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n", 764cf824788SJanosch Machowinski current_count)); 7651da177e4SLinus Torvalds 7661da177e4SLinus Torvalds /* Validate number of power states discovered */ 767cf824788SJanosch Machowinski if (current_count < 2) 7686d93c648SVenkatesh Pallipadi status = -EFAULT; 7691da177e4SLinus Torvalds 7701da177e4SLinus Torvalds end: 77102438d87SLen Brown kfree(buffer.pointer); 7721da177e4SLinus Torvalds 773d550d98dSPatrick Mochel return status; 7741da177e4SLinus Torvalds } 7751da177e4SLinus Torvalds 7761da177e4SLinus Torvalds static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) 7771da177e4SLinus Torvalds { 7781da177e4SLinus Torvalds 7791da177e4SLinus Torvalds if (!cx->address) 780d550d98dSPatrick Mochel return; 7811da177e4SLinus Torvalds 7821da177e4SLinus Torvalds /* 7831da177e4SLinus Torvalds * C2 latency must be less than or equal to 100 7841da177e4SLinus Torvalds * microseconds. 7851da177e4SLinus Torvalds */ 7861da177e4SLinus Torvalds else if (cx->latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { 7871da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 7884be44fcdSLen Brown "latency too large [%d]\n", cx->latency)); 789d550d98dSPatrick Mochel return; 7901da177e4SLinus Torvalds } 7911da177e4SLinus Torvalds 7921da177e4SLinus Torvalds /* 7931da177e4SLinus Torvalds * Otherwise we've met all of our C2 requirements. 7941da177e4SLinus Torvalds * Normalize the C2 latency to expidite policy 7951da177e4SLinus Torvalds */ 7961da177e4SLinus Torvalds cx->valid = 1; 7971da177e4SLinus Torvalds cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); 7981da177e4SLinus Torvalds 799d550d98dSPatrick Mochel return; 8001da177e4SLinus Torvalds } 8011da177e4SLinus Torvalds 8024be44fcdSLen Brown static void acpi_processor_power_verify_c3(struct acpi_processor *pr, 8031da177e4SLinus Torvalds struct acpi_processor_cx *cx) 8041da177e4SLinus Torvalds { 80502df8b93SVenkatesh Pallipadi static int bm_check_flag; 80602df8b93SVenkatesh Pallipadi 8071da177e4SLinus Torvalds 8081da177e4SLinus Torvalds if (!cx->address) 809d550d98dSPatrick Mochel return; 8101da177e4SLinus Torvalds 8111da177e4SLinus Torvalds /* 8121da177e4SLinus Torvalds * C3 latency must be less than or equal to 1000 8131da177e4SLinus Torvalds * microseconds. 8141da177e4SLinus Torvalds */ 8151da177e4SLinus Torvalds else if (cx->latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { 8161da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 8174be44fcdSLen Brown "latency too large [%d]\n", cx->latency)); 818d550d98dSPatrick Mochel return; 8191da177e4SLinus Torvalds } 8201da177e4SLinus Torvalds 8211da177e4SLinus Torvalds /* 8221da177e4SLinus Torvalds * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) 8231da177e4SLinus Torvalds * DMA transfers are used by any ISA device to avoid livelock. 8241da177e4SLinus Torvalds * Note that we could disable Type-F DMA (as recommended by 8251da177e4SLinus Torvalds * the erratum), but this is known to disrupt certain ISA 8261da177e4SLinus Torvalds * devices thus we take the conservative approach. 8271da177e4SLinus Torvalds */ 8281da177e4SLinus Torvalds else if (errata.piix4.fdma) { 8291da177e4SLinus Torvalds ACPI_DEBUG_PRINT((ACPI_DB_INFO, 8301da177e4SLinus Torvalds "C3 not supported on PIIX4 with Type-F DMA\n")); 831d550d98dSPatrick Mochel return; 8321da177e4SLinus Torvalds } 8331da177e4SLinus Torvalds 83402df8b93SVenkatesh Pallipadi /* All the logic here assumes flags.bm_check is same across all CPUs */ 83502df8b93SVenkatesh Pallipadi if (!bm_check_flag) { 83602df8b93SVenkatesh Pallipadi /* Determine whether bm_check is needed based on CPU */ 83702df8b93SVenkatesh Pallipadi acpi_processor_power_init_bm_check(&(pr->flags), pr->id); 83802df8b93SVenkatesh Pallipadi bm_check_flag = pr->flags.bm_check; 83902df8b93SVenkatesh Pallipadi } else { 84002df8b93SVenkatesh Pallipadi pr->flags.bm_check = bm_check_flag; 84102df8b93SVenkatesh Pallipadi } 84202df8b93SVenkatesh Pallipadi 84302df8b93SVenkatesh Pallipadi if (pr->flags.bm_check) { 84402df8b93SVenkatesh Pallipadi /* bus mastering control is necessary */ 84502df8b93SVenkatesh Pallipadi if (!pr->flags.bm_control) { 84602df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 84702df8b93SVenkatesh Pallipadi "C3 support requires bus mastering control\n")); 848d550d98dSPatrick Mochel return; 84902df8b93SVenkatesh Pallipadi } 85002df8b93SVenkatesh Pallipadi } else { 85102df8b93SVenkatesh Pallipadi /* 85202df8b93SVenkatesh Pallipadi * WBINVD should be set in fadt, for C3 state to be 85302df8b93SVenkatesh Pallipadi * supported on when bm_check is not required. 85402df8b93SVenkatesh Pallipadi */ 85502df8b93SVenkatesh Pallipadi if (acpi_fadt.wb_invd != 1) { 85602df8b93SVenkatesh Pallipadi ACPI_DEBUG_PRINT((ACPI_DB_INFO, 85702df8b93SVenkatesh Pallipadi "Cache invalidation should work properly" 85802df8b93SVenkatesh Pallipadi " for C3 to be enabled on SMP systems\n")); 859d550d98dSPatrick Mochel return; 86002df8b93SVenkatesh Pallipadi } 86102df8b93SVenkatesh Pallipadi acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 86202df8b93SVenkatesh Pallipadi 0, ACPI_MTX_DO_NOT_LOCK); 86302df8b93SVenkatesh Pallipadi } 86402df8b93SVenkatesh Pallipadi 8651da177e4SLinus Torvalds /* 8661da177e4SLinus Torvalds * Otherwise we've met all of our C3 requirements. 8671da177e4SLinus Torvalds * Normalize the C3 latency to expidite policy. Enable 8681da177e4SLinus Torvalds * checking of bus mastering status (bm_check) so we can 8691da177e4SLinus Torvalds * use this in our C3 policy 8701da177e4SLinus Torvalds */ 8711da177e4SLinus Torvalds cx->valid = 1; 8721da177e4SLinus Torvalds cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); 8731da177e4SLinus Torvalds 874d550d98dSPatrick Mochel return; 8751da177e4SLinus Torvalds } 8761da177e4SLinus Torvalds 8771da177e4SLinus Torvalds static int acpi_processor_power_verify(struct acpi_processor *pr) 8781da177e4SLinus Torvalds { 8791da177e4SLinus Torvalds unsigned int i; 8801da177e4SLinus Torvalds unsigned int working = 0; 8816eb0a0fdSVenkatesh Pallipadi 882bd663347SAndi Kleen #ifdef ARCH_APICTIMER_STOPS_ON_C3 8830b5c59a1SAndi Kleen int timer_broadcast = 0; 8840b5c59a1SAndi Kleen cpumask_t mask = cpumask_of_cpu(pr->id); 8856eb0a0fdSVenkatesh Pallipadi on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1); 8866eb0a0fdSVenkatesh Pallipadi #endif 8876eb0a0fdSVenkatesh Pallipadi 8881da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 8891da177e4SLinus Torvalds struct acpi_processor_cx *cx = &pr->power.states[i]; 8901da177e4SLinus Torvalds 8911da177e4SLinus Torvalds switch (cx->type) { 8921da177e4SLinus Torvalds case ACPI_STATE_C1: 8931da177e4SLinus Torvalds cx->valid = 1; 8941da177e4SLinus Torvalds break; 8951da177e4SLinus Torvalds 8961da177e4SLinus Torvalds case ACPI_STATE_C2: 8971da177e4SLinus Torvalds acpi_processor_power_verify_c2(cx); 898bd663347SAndi Kleen #ifdef ARCH_APICTIMER_STOPS_ON_C3 899bd663347SAndi Kleen /* Some AMD systems fake C3 as C2, but still 900bd663347SAndi Kleen have timer troubles */ 901bd663347SAndi Kleen if (cx->valid && 902bd663347SAndi Kleen boot_cpu_data.x86_vendor == X86_VENDOR_AMD) 903bd663347SAndi Kleen timer_broadcast++; 904bd663347SAndi Kleen #endif 9051da177e4SLinus Torvalds break; 9061da177e4SLinus Torvalds 9071da177e4SLinus Torvalds case ACPI_STATE_C3: 9081da177e4SLinus Torvalds acpi_processor_power_verify_c3(pr, cx); 9096eb0a0fdSVenkatesh Pallipadi #ifdef ARCH_APICTIMER_STOPS_ON_C3 910bd663347SAndi Kleen if (cx->valid) 911bd663347SAndi Kleen timer_broadcast++; 9126eb0a0fdSVenkatesh Pallipadi #endif 9131da177e4SLinus Torvalds break; 9141da177e4SLinus Torvalds } 9151da177e4SLinus Torvalds 9161da177e4SLinus Torvalds if (cx->valid) 9171da177e4SLinus Torvalds working++; 9181da177e4SLinus Torvalds } 9191da177e4SLinus Torvalds 9200b5c59a1SAndi Kleen #ifdef ARCH_APICTIMER_STOPS_ON_C3 921bd663347SAndi Kleen if (timer_broadcast) 922bd663347SAndi Kleen on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1); 9230b5c59a1SAndi Kleen #endif 924bd663347SAndi Kleen 9251da177e4SLinus Torvalds return (working); 9261da177e4SLinus Torvalds } 9271da177e4SLinus Torvalds 9284be44fcdSLen Brown static int acpi_processor_get_power_info(struct acpi_processor *pr) 9291da177e4SLinus Torvalds { 9301da177e4SLinus Torvalds unsigned int i; 9311da177e4SLinus Torvalds int result; 9321da177e4SLinus Torvalds 9331da177e4SLinus Torvalds 9341da177e4SLinus Torvalds /* NOTE: the idle thread may not be running while calling 9351da177e4SLinus Torvalds * this function */ 9361da177e4SLinus Torvalds 937cf824788SJanosch Machowinski /* Adding C1 state */ 938cf824788SJanosch Machowinski acpi_processor_get_power_info_default_c1(pr); 9391da177e4SLinus Torvalds result = acpi_processor_get_power_info_cst(pr); 9406d93c648SVenkatesh Pallipadi if (result == -ENODEV) 941cf824788SJanosch Machowinski acpi_processor_get_power_info_fadt(pr); 9426d93c648SVenkatesh Pallipadi 943cf824788SJanosch Machowinski pr->power.count = acpi_processor_power_verify(pr); 9441da177e4SLinus Torvalds 9451da177e4SLinus Torvalds /* 9461da177e4SLinus Torvalds * Set Default Policy 9471da177e4SLinus Torvalds * ------------------ 9481da177e4SLinus Torvalds * Now that we know which states are supported, set the default 9491da177e4SLinus Torvalds * policy. Note that this policy can be changed dynamically 9501da177e4SLinus Torvalds * (e.g. encourage deeper sleeps to conserve battery life when 9511da177e4SLinus Torvalds * not on AC). 9521da177e4SLinus Torvalds */ 9531da177e4SLinus Torvalds result = acpi_processor_set_power_policy(pr); 9541da177e4SLinus Torvalds if (result) 955d550d98dSPatrick Mochel return result; 9561da177e4SLinus Torvalds 9571da177e4SLinus Torvalds /* 9581da177e4SLinus Torvalds * if one state of type C2 or C3 is available, mark this 9591da177e4SLinus Torvalds * CPU as being "idle manageable" 9601da177e4SLinus Torvalds */ 9611da177e4SLinus Torvalds for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 962acf05f4bSVenkatesh Pallipadi if (pr->power.states[i].valid) { 9631da177e4SLinus Torvalds pr->power.count = i; 9642203d6edSLinus Torvalds if (pr->power.states[i].type >= ACPI_STATE_C2) 9651da177e4SLinus Torvalds pr->flags.power = 1; 9661da177e4SLinus Torvalds } 967acf05f4bSVenkatesh Pallipadi } 9681da177e4SLinus Torvalds 969d550d98dSPatrick Mochel return 0; 9701da177e4SLinus Torvalds } 9711da177e4SLinus Torvalds 9721da177e4SLinus Torvalds int acpi_processor_cst_has_changed(struct acpi_processor *pr) 9731da177e4SLinus Torvalds { 9741da177e4SLinus Torvalds int result = 0; 9751da177e4SLinus Torvalds 9761da177e4SLinus Torvalds 9771da177e4SLinus Torvalds if (!pr) 978d550d98dSPatrick Mochel return -EINVAL; 9791da177e4SLinus Torvalds 98002df8b93SVenkatesh Pallipadi if (nocst) { 981d550d98dSPatrick Mochel return -ENODEV; 9821da177e4SLinus Torvalds } 9831da177e4SLinus Torvalds 9841da177e4SLinus Torvalds if (!pr->flags.power_setup_done) 985d550d98dSPatrick Mochel return -ENODEV; 9861da177e4SLinus Torvalds 9871da177e4SLinus Torvalds /* Fall back to the default idle loop */ 9881da177e4SLinus Torvalds pm_idle = pm_idle_save; 989fbd568a3SPaul E. McKenney synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ 9901da177e4SLinus Torvalds 9911da177e4SLinus Torvalds pr->flags.power = 0; 9921da177e4SLinus Torvalds result = acpi_processor_get_power_info(pr); 9931da177e4SLinus Torvalds if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) 9941da177e4SLinus Torvalds pm_idle = acpi_processor_idle; 9951da177e4SLinus Torvalds 996d550d98dSPatrick Mochel return result; 9971da177e4SLinus Torvalds } 9981da177e4SLinus Torvalds 9991da177e4SLinus Torvalds /* proc interface */ 10001da177e4SLinus Torvalds 10011da177e4SLinus Torvalds static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) 10021da177e4SLinus Torvalds { 10031da177e4SLinus Torvalds struct acpi_processor *pr = (struct acpi_processor *)seq->private; 10041da177e4SLinus Torvalds unsigned int i; 10051da177e4SLinus Torvalds 10061da177e4SLinus Torvalds 10071da177e4SLinus Torvalds if (!pr) 10081da177e4SLinus Torvalds goto end; 10091da177e4SLinus Torvalds 10101da177e4SLinus Torvalds seq_printf(seq, "active state: C%zd\n" 10111da177e4SLinus Torvalds "max_cstate: C%d\n" 10121da177e4SLinus Torvalds "bus master activity: %08x\n", 10131da177e4SLinus Torvalds pr->power.state ? pr->power.state - pr->power.states : 0, 10144be44fcdSLen Brown max_cstate, (unsigned)pr->power.bm_activity); 10151da177e4SLinus Torvalds 10161da177e4SLinus Torvalds seq_puts(seq, "states:\n"); 10171da177e4SLinus Torvalds 10181da177e4SLinus Torvalds for (i = 1; i <= pr->power.count; i++) { 10191da177e4SLinus Torvalds seq_printf(seq, " %cC%d: ", 10204be44fcdSLen Brown (&pr->power.states[i] == 10214be44fcdSLen Brown pr->power.state ? '*' : ' '), i); 10221da177e4SLinus Torvalds 10231da177e4SLinus Torvalds if (!pr->power.states[i].valid) { 10241da177e4SLinus Torvalds seq_puts(seq, "<not supported>\n"); 10251da177e4SLinus Torvalds continue; 10261da177e4SLinus Torvalds } 10271da177e4SLinus Torvalds 10281da177e4SLinus Torvalds switch (pr->power.states[i].type) { 10291da177e4SLinus Torvalds case ACPI_STATE_C1: 10301da177e4SLinus Torvalds seq_printf(seq, "type[C1] "); 10311da177e4SLinus Torvalds break; 10321da177e4SLinus Torvalds case ACPI_STATE_C2: 10331da177e4SLinus Torvalds seq_printf(seq, "type[C2] "); 10341da177e4SLinus Torvalds break; 10351da177e4SLinus Torvalds case ACPI_STATE_C3: 10361da177e4SLinus Torvalds seq_printf(seq, "type[C3] "); 10371da177e4SLinus Torvalds break; 10381da177e4SLinus Torvalds default: 10391da177e4SLinus Torvalds seq_printf(seq, "type[--] "); 10401da177e4SLinus Torvalds break; 10411da177e4SLinus Torvalds } 10421da177e4SLinus Torvalds 10431da177e4SLinus Torvalds if (pr->power.states[i].promotion.state) 10441da177e4SLinus Torvalds seq_printf(seq, "promotion[C%zd] ", 10451da177e4SLinus Torvalds (pr->power.states[i].promotion.state - 10461da177e4SLinus Torvalds pr->power.states)); 10471da177e4SLinus Torvalds else 10481da177e4SLinus Torvalds seq_puts(seq, "promotion[--] "); 10491da177e4SLinus Torvalds 10501da177e4SLinus Torvalds if (pr->power.states[i].demotion.state) 10511da177e4SLinus Torvalds seq_printf(seq, "demotion[C%zd] ", 10521da177e4SLinus Torvalds (pr->power.states[i].demotion.state - 10531da177e4SLinus Torvalds pr->power.states)); 10541da177e4SLinus Torvalds else 10551da177e4SLinus Torvalds seq_puts(seq, "demotion[--] "); 10561da177e4SLinus Torvalds 1057a3c6598fSDominik Brodowski seq_printf(seq, "latency[%03d] usage[%08d] duration[%020llu]\n", 10581da177e4SLinus Torvalds pr->power.states[i].latency, 1059a3c6598fSDominik Brodowski pr->power.states[i].usage, 1060a3c6598fSDominik Brodowski pr->power.states[i].time); 10611da177e4SLinus Torvalds } 10621da177e4SLinus Torvalds 10631da177e4SLinus Torvalds end: 1064d550d98dSPatrick Mochel return 0; 10651da177e4SLinus Torvalds } 10661da177e4SLinus Torvalds 10671da177e4SLinus Torvalds static int acpi_processor_power_open_fs(struct inode *inode, struct file *file) 10681da177e4SLinus Torvalds { 10691da177e4SLinus Torvalds return single_open(file, acpi_processor_power_seq_show, 10701da177e4SLinus Torvalds PDE(inode)->data); 10711da177e4SLinus Torvalds } 10721da177e4SLinus Torvalds 1073*d7508032SArjan van de Ven static const struct file_operations acpi_processor_power_fops = { 10741da177e4SLinus Torvalds .open = acpi_processor_power_open_fs, 10751da177e4SLinus Torvalds .read = seq_read, 10761da177e4SLinus Torvalds .llseek = seq_lseek, 10771da177e4SLinus Torvalds .release = single_release, 10781da177e4SLinus Torvalds }; 10791da177e4SLinus Torvalds 10804be44fcdSLen Brown int acpi_processor_power_init(struct acpi_processor *pr, 10814be44fcdSLen Brown struct acpi_device *device) 10821da177e4SLinus Torvalds { 10831da177e4SLinus Torvalds acpi_status status = 0; 1084b6835052SAndreas Mohr static int first_run; 10851da177e4SLinus Torvalds struct proc_dir_entry *entry = NULL; 10861da177e4SLinus Torvalds unsigned int i; 10871da177e4SLinus Torvalds 10881da177e4SLinus Torvalds 10891da177e4SLinus Torvalds if (!first_run) { 10901da177e4SLinus Torvalds dmi_check_system(processor_power_dmi_table); 10911da177e4SLinus Torvalds if (max_cstate < ACPI_C_STATES_MAX) 10924be44fcdSLen Brown printk(KERN_NOTICE 10934be44fcdSLen Brown "ACPI: processor limited to max C-state %d\n", 10944be44fcdSLen Brown max_cstate); 10951da177e4SLinus Torvalds first_run++; 10961da177e4SLinus Torvalds } 10971da177e4SLinus Torvalds 109802df8b93SVenkatesh Pallipadi if (!pr) 1099d550d98dSPatrick Mochel return -EINVAL; 110002df8b93SVenkatesh Pallipadi 110102df8b93SVenkatesh Pallipadi if (acpi_fadt.cst_cnt && !nocst) { 11024be44fcdSLen Brown status = 11034be44fcdSLen Brown acpi_os_write_port(acpi_fadt.smi_cmd, acpi_fadt.cst_cnt, 8); 11041da177e4SLinus Torvalds if (ACPI_FAILURE(status)) { 1105a6fc6720SThomas Renninger ACPI_EXCEPTION((AE_INFO, status, 1106a6fc6720SThomas Renninger "Notifying BIOS of _CST ability failed")); 11071da177e4SLinus Torvalds } 11081da177e4SLinus Torvalds } 11091da177e4SLinus Torvalds 11101da177e4SLinus Torvalds acpi_processor_get_power_info(pr); 11111da177e4SLinus Torvalds 11121da177e4SLinus Torvalds /* 11131da177e4SLinus Torvalds * Install the idle handler if processor power management is supported. 11141da177e4SLinus Torvalds * Note that we use previously set idle handler will be used on 11151da177e4SLinus Torvalds * platforms that only support C1. 11161da177e4SLinus Torvalds */ 11171da177e4SLinus Torvalds if ((pr->flags.power) && (!boot_option_idle_override)) { 11181da177e4SLinus Torvalds printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); 11191da177e4SLinus Torvalds for (i = 1; i <= pr->power.count; i++) 11201da177e4SLinus Torvalds if (pr->power.states[i].valid) 11214be44fcdSLen Brown printk(" C%d[C%d]", i, 11224be44fcdSLen Brown pr->power.states[i].type); 11231da177e4SLinus Torvalds printk(")\n"); 11241da177e4SLinus Torvalds 11251da177e4SLinus Torvalds if (pr->id == 0) { 11261da177e4SLinus Torvalds pm_idle_save = pm_idle; 11271da177e4SLinus Torvalds pm_idle = acpi_processor_idle; 11281da177e4SLinus Torvalds } 11291da177e4SLinus Torvalds } 11301da177e4SLinus Torvalds 11311da177e4SLinus Torvalds /* 'power' [R] */ 11321da177e4SLinus Torvalds entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER, 11331da177e4SLinus Torvalds S_IRUGO, acpi_device_dir(device)); 11341da177e4SLinus Torvalds if (!entry) 1135a6fc6720SThomas Renninger return -EIO; 11361da177e4SLinus Torvalds else { 11371da177e4SLinus Torvalds entry->proc_fops = &acpi_processor_power_fops; 11381da177e4SLinus Torvalds entry->data = acpi_driver_data(device); 11391da177e4SLinus Torvalds entry->owner = THIS_MODULE; 11401da177e4SLinus Torvalds } 11411da177e4SLinus Torvalds 11421da177e4SLinus Torvalds pr->flags.power_setup_done = 1; 11431da177e4SLinus Torvalds 1144d550d98dSPatrick Mochel return 0; 11451da177e4SLinus Torvalds } 11461da177e4SLinus Torvalds 11474be44fcdSLen Brown int acpi_processor_power_exit(struct acpi_processor *pr, 11484be44fcdSLen Brown struct acpi_device *device) 11491da177e4SLinus Torvalds { 11501da177e4SLinus Torvalds 11511da177e4SLinus Torvalds pr->flags.power_setup_done = 0; 11521da177e4SLinus Torvalds 11531da177e4SLinus Torvalds if (acpi_device_dir(device)) 11544be44fcdSLen Brown remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, 11554be44fcdSLen Brown acpi_device_dir(device)); 11561da177e4SLinus Torvalds 11571da177e4SLinus Torvalds /* Unregister the idle handler when processor #0 is removed. */ 11581da177e4SLinus Torvalds if (pr->id == 0) { 11591da177e4SLinus Torvalds pm_idle = pm_idle_save; 11601da177e4SLinus Torvalds 11611da177e4SLinus Torvalds /* 11621da177e4SLinus Torvalds * We are about to unload the current idle thread pm callback 11631da177e4SLinus Torvalds * (pm_idle), Wait for all processors to update cached/local 11641da177e4SLinus Torvalds * copies of pm_idle before proceeding. 11651da177e4SLinus Torvalds */ 11661da177e4SLinus Torvalds cpu_idle_wait(); 11671da177e4SLinus Torvalds } 11681da177e4SLinus Torvalds 1169d550d98dSPatrick Mochel return 0; 11701da177e4SLinus Torvalds } 1171