diff options
Diffstat (limited to 'drivers/acpi/processor_idle.c')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 608 |
1 files changed, 0 insertions, 608 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 7eab733ae96..7bc22a471fe 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -66,43 +66,17 @@ ACPI_MODULE_NAME("processor_idle"); #define ACPI_PROCESSOR_FILE_POWER "power" #define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000) #define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY) -#ifndef CONFIG_CPU_IDLE -#define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */ -#define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */ -static void (*pm_idle_save) (void) __read_mostly; -#else #define C2_OVERHEAD 1 /* 1us */ #define C3_OVERHEAD 1 /* 1us */ -#endif #define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000)) static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER; -#ifdef CONFIG_CPU_IDLE module_param(max_cstate, uint, 0000); -#else -module_param(max_cstate, uint, 0644); -#endif static unsigned int nocst __read_mostly; module_param(nocst, uint, 0000); -#ifndef CONFIG_CPU_IDLE -/* - * bm_history -- bit-mask with a bit per jiffy of bus-master activity - * 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms - * 800 HZ: 0xFFFFFFFF: 32 jiffies = 40ms - * 100 HZ: 0x0000000F: 4 jiffies = 40ms - * reduce history for more aggressive entry into C3 - */ -static unsigned int bm_history __read_mostly = - (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); -module_param(bm_history, uint, 0644); - -static int acpi_processor_set_power_policy(struct acpi_processor *pr); - -#else /* CONFIG_CPU_IDLE */ static unsigned int latency_factor __read_mostly = 2; module_param(latency_factor, uint, 0644); -#endif /* * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. @@ -224,51 +198,6 @@ static void acpi_safe_halt(void) current_thread_info()->status |= TS_POLLING; } -#ifndef CONFIG_CPU_IDLE - -static void -acpi_processor_power_activate(struct acpi_processor *pr, - struct acpi_processor_cx *new) -{ - struct acpi_processor_cx *old; - - if (!pr || !new) - return; - - old = pr->power.state; - - if (old) - old->promotion.count = 0; - new->demotion.count = 0; - - pr->power.state = new; - - return; -} - -static atomic_t c3_cpu_count; - -/* Common C-state entry for C2, C3, .. */ -static void acpi_cstate_enter(struct acpi_processor_cx *cstate) -{ - /* Don't trace irqs off for idle */ - stop_critical_timings(); - if (cstate->entry_method == ACPI_CSTATE_FFH) { - /* Call into architectural FFH based C-state */ - acpi_processor_ffh_cstate_enter(cstate); - } else { - int unused; - /* IO port based C-state */ - inb(cstate->address); - /* Dummy wait op - must do something useless after P_LVL2 read - because chipsets cannot guarantee that STPCLK# signal - gets asserted in time to freeze execution properly. */ - unused = inl(acpi_gbl_FADT.xpm_timer_block.address); - } - start_critical_timings(); -} -#endif /* !CONFIG_CPU_IDLE */ - #ifdef ARCH_APICTIMER_STOPS_ON_C3 /* @@ -370,421 +299,6 @@ static int tsc_halts_in_c(int state) } #endif -#ifndef CONFIG_CPU_IDLE -static void acpi_processor_idle(void) -{ - struct acpi_processor *pr = NULL; - struct acpi_processor_cx *cx = NULL; - struct acpi_processor_cx *next_state = NULL; - int sleep_ticks = 0; - u32 t1, t2 = 0; - - /* - * Interrupts must be disabled during bus mastering calculations and - * for C2/C3 transitions. - */ - local_irq_disable(); - - pr = __get_cpu_var(processors); - if (!pr) { - local_irq_enable(); - return; - } - - /* - * Check whether we truly need to go idle, or should - * reschedule: - */ - if (unlikely(need_resched())) { - local_irq_enable(); - return; - } - - cx = pr->power.state; - if (!cx || acpi_idle_suspend) { - if (pm_idle_save) { - pm_idle_save(); /* enables IRQs */ - } else { - acpi_safe_halt(); - local_irq_enable(); - } - - return; - } - - /* - * Check BM Activity - * ----------------- - * Check for bus mastering activity (if required), record, and check - * for demotion. - */ - if (pr->flags.bm_check) { - u32 bm_status = 0; - unsigned long diff = jiffies - pr->power.bm_check_timestamp; - - if (diff > 31) - diff = 31; - - pr->power.bm_activity <<= diff; - - acpi_get_register_unlocked(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); - if (bm_status) { - pr->power.bm_activity |= 0x1; - acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); - } - /* - * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect - * the true state of bus mastering activity; forcing us to - * manually check the BMIDEA bit of each IDE channel. - */ - else if (errata.piix4.bmisx) { - if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) - || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) - pr->power.bm_activity |= 0x1; - } - - pr->power.bm_check_timestamp = jiffies; - - /* - * If bus mastering is or was active this jiffy, demote - * to avoid a faulty transition. Note that the processor - * won't enter a low-power state during this call (to this - * function) but should upon the next. - * - * TBD: A better policy might be to fallback to the demotion - * state (use it for this quantum only) istead of - * demoting -- and rely on duration as our sole demotion - * qualification. This may, however, introduce DMA - * issues (e.g. floppy DMA transfer overrun/underrun). - */ - if ((pr->power.bm_activity & 0x1) && - cx->demotion.threshold.bm) { - local_irq_enable(); - next_state = cx->demotion.state; - goto end; - } - } - -#ifdef CONFIG_HOTPLUG_CPU - /* - * Check for P_LVL2_UP flag before entering C2 and above on - * an SMP system. We do it here instead of doing it at _CST/P_LVL - * detection phase, to work cleanly with logical CPU hotplug. - */ - if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && - !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) - cx = &pr->power.states[ACPI_STATE_C1]; -#endif - - /* - * Sleep: - * ------ - * Invoke the current Cx state to put the processor to sleep. - */ - if (cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) { - current_thread_info()->status &= ~TS_POLLING; - /* - * TS_POLLING-cleared state must be visible before we - * test NEED_RESCHED: - */ - smp_mb(); - if (need_resched()) { - current_thread_info()->status |= TS_POLLING; - local_irq_enable(); - return; - } - } - - switch (cx->type) { - - case ACPI_STATE_C1: - /* - * Invoke C1. - * Use the appropriate idle routine, the one that would - * be used without acpi C-states. - */ - if (pm_idle_save) { - pm_idle_save(); /* enables IRQs */ - } else { - acpi_safe_halt(); - local_irq_enable(); - } - - /* - * TBD: Can't get time duration while in C1, as resumes - * go to an ISR rather than here. Need to instrument - * base interrupt handler. - * - * Note: the TSC better not stop in C1, sched_clock() will - * skew otherwise. - */ - sleep_ticks = 0xFFFFFFFF; - - break; - - case ACPI_STATE_C2: - /* Get start time (ticks) */ - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); - /* Tell the scheduler that we are going deep-idle: */ - sched_clock_idle_sleep_event(); - /* Invoke C2 */ - acpi_state_timer_broadcast(pr, cx, 1); - acpi_cstate_enter(cx); - /* Get end time (ticks) */ - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); - -#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) - /* TSC halts in C2, so notify users */ - if (tsc_halts_in_c(ACPI_STATE_C2)) - mark_tsc_unstable("possible TSC halt in C2"); -#endif - /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = ticks_elapsed(t1, t2); - - /* Tell the scheduler how much we idled: */ - sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); - - /* Re-enable interrupts */ - local_irq_enable(); - /* Do not account our idle-switching overhead: */ - sleep_ticks -= cx->latency_ticks + C2_OVERHEAD; - - current_thread_info()->status |= TS_POLLING; - acpi_state_timer_broadcast(pr, cx, 0); - break; - - case ACPI_STATE_C3: - acpi_unlazy_tlb(smp_processor_id()); - /* - * Must be done before busmaster disable as we might - * need to access HPET ! - */ - acpi_state_timer_broadcast(pr, cx, 1); - /* - * disable bus master - * bm_check implies we need ARB_DIS - * !bm_check implies we need cache flush - * bm_control implies whether we can do ARB_DIS - * - * That leaves a case where bm_check is set and bm_control is - * not set. In that case we cannot do much, we enter C3 - * without doing anything. - */ - if (pr->flags.bm_check && pr->flags.bm_control) { - if (atomic_inc_return(&c3_cpu_count) == - num_online_cpus()) { - /* - * All CPUs are trying to go to C3 - * Disable bus master arbitration - */ - acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1); - } - } else if (!pr->flags.bm_check) { - /* SMP with no shared cache... Invalidate cache */ - ACPI_FLUSH_CPU_CACHE(); - } - - /* Get start time (ticks) */ - t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); - /* Invoke C3 */ - /* Tell the scheduler that we are going deep-idle: */ - sched_clock_idle_sleep_event(); - acpi_cstate_enter(cx); - /* Get end time (ticks) */ - t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); - if (pr->flags.bm_check && pr->flags.bm_control) { - /* Enable bus master arbitration */ - atomic_dec(&c3_cpu_count); - acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0); - } - -#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86) - /* TSC halts in C3, so notify users */ - if (tsc_halts_in_c(ACPI_STATE_C3)) - mark_tsc_unstable("TSC halts in C3"); -#endif - /* Compute time (ticks) that we were actually asleep */ - sleep_ticks = ticks_elapsed(t1, t2); - /* Tell the scheduler how much we idled: */ - sched_clock_idle_wakeup_event(sleep_ticks*PM_TIMER_TICK_NS); - - /* Re-enable interrupts */ - local_irq_enable(); - /* Do not account our idle-switching overhead: */ - sleep_ticks -= cx->latency_ticks + C3_OVERHEAD; - - current_thread_info()->status |= TS_POLLING; - acpi_state_timer_broadcast(pr, cx, 0); - break; - - default: - local_irq_enable(); - return; - } - cx->usage++; - if ((cx->type != ACPI_STATE_C1) && (sleep_ticks > 0)) - cx->time += sleep_ticks; - - next_state = pr->power.state; - -#ifdef CONFIG_HOTPLUG_CPU - /* Don't do promotion/demotion */ - if ((cx->type == ACPI_STATE_C1) && (num_online_cpus() > 1) && - !pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) { - next_state = cx; - goto end; - } -#endif - - /* - * Promotion? - * ---------- - * Track the number of longs (time asleep is greater than threshold) - * and promote when the count threshold is reached. Note that bus - * mastering activity may prevent promotions. - * Do not promote above max_cstate. - */ - if (cx->promotion.state && - ((cx->promotion.state - pr->power.states) <= max_cstate)) { - if (sleep_ticks > cx->promotion.threshold.ticks && - cx->promotion.state->latency <= - pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY)) { - cx->promotion.count++; - cx->demotion.count = 0; - if (cx->promotion.count >= - cx->promotion.threshold.count) { - if (pr->flags.bm_check) { - if (! - (pr->power.bm_activity & cx-> - promotion.threshold.bm)) { - next_state = - cx->promotion.state; - goto end; - } - } else { - next_state = cx->promotion.state; - goto end; - } - } - } - } - - /* - * Demotion? - * --------- - * Track the number of shorts (time asleep is less than time threshold) - * and demote when the usage threshold is reached. - */ - if (cx->demotion.state) { - if (sleep_ticks < cx->demotion.threshold.ticks) { - cx->demotion.count++; - cx->promotion.count = 0; - if (cx->demotion.count >= cx->demotion.threshold.count) { - next_state = cx->demotion.state; - goto end; - } - } - } - - end: - /* - * Demote if current state exceeds max_cstate - * or if the latency of the current state is unacceptable - */ - if ((pr->power.state - pr->power.states) > max_cstate || - pr->power.state->latency > - pm_qos_requirement(PM_QOS_CPU_DMA_LATENCY)) { - if (cx->demotion.state) - next_state = cx->demotion.state; - } - - /* - * New Cx State? - * ------------- - * If we're going to start using a new Cx state we must clean up - * from the previous and prepare to use the new. - */ - if (next_state != pr->power.state) - acpi_processor_power_activate(pr, next_state); -} - -static int acpi_processor_set_power_policy(struct acpi_processor *pr) -{ - unsigned int i; - unsigned int state_is_set = 0; - struct acpi_processor_cx *lower = NULL; - struct acpi_processor_cx *higher = NULL; - struct acpi_processor_cx *cx; - - - if (!pr) - return -EINVAL; - - /* - * This function sets the default Cx state policy (OS idle handler). - * Our scheme is to promote quickly to C2 but more conservatively - * to C3. We're favoring C2 for its characteristics of low latency - * (quick response), good power savings, and ability to allow bus - * mastering activity. Note that the Cx state policy is completely - * customizable and can be altered dynamically. - */ - - /* startup state */ - for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { - cx = &pr->power.states[i]; - if (!cx->valid) - continue; - - if (!state_is_set) - pr->power.state = cx; - state_is_set++; - break; - } - - if (!state_is_set) - return -ENODEV; - - /* demotion */ - for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { - cx = &pr->power.states[i]; - if (!cx->valid) - continue; - - if (lower) { - cx->demotion.state = lower; - cx->demotion.threshold.ticks = cx->latency_ticks; - cx->demotion.threshold.count = 1; - if (cx->type == ACPI_STATE_C3) - cx->demotion.threshold.bm = bm_history; - } - - lower = cx; - } - - /* promotion */ - for (i = (ACPI_PROCESSOR_MAX_POWER - 1); i > 0; i--) { - cx = &pr->power.states[i]; - if (!cx->valid) - continue; - - if (higher) { - cx->promotion.state = higher; - cx->promotion.threshold.ticks = cx->latency_ticks; - if (cx->type >= ACPI_STATE_C2) - cx->promotion.threshold.count = 4; - else - cx->promotion.threshold.count = 10; - if (higher->type == ACPI_STATE_C3) - cx->promotion.threshold.bm = bm_history; - } - - higher = cx; - } - - return 0; -} -#endif /* !CONFIG_CPU_IDLE */ - static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) { @@ -1027,11 +541,7 @@ static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) */ cx->valid = 1; -#ifndef CONFIG_CPU_IDLE - cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); -#else cx->latency_ticks = cx->latency; -#endif return; } @@ -1111,11 +621,7 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr, */ cx->valid = 1; -#ifndef CONFIG_CPU_IDLE - cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency); -#else cx->latency_ticks = cx->latency; -#endif /* * On older chipsets, BM_RLD needs to be set * in order for Bus Master activity to wake the @@ -1189,20 +695,6 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr) pr->power.count = acpi_processor_power_verify(pr); -#ifndef CONFIG_CPU_IDLE - /* - * Set Default Policy - * ------------------ - * Now that we know which states are supported, set the default - * policy. Note that this policy can be changed dynamically - * (e.g. encourage deeper sleeps to conserve battery life when - * not on AC). - */ - result = acpi_processor_set_power_policy(pr); - if (result) - return result; -#endif - /* * if one state of type C2 or C3 is available, mark this * CPU as being "idle manageable" @@ -1300,69 +792,6 @@ static const struct file_operations acpi_processor_power_fops = { .release = single_release, }; -#ifndef CONFIG_CPU_IDLE - -int acpi_processor_cst_has_changed(struct acpi_processor *pr) -{ - int result = 0; - - if (boot_option_idle_override) - return 0; - - if (!pr) - return -EINVAL; - - if (nocst) { - return -ENODEV; - } - - if (!pr->flags.power_setup_done) - return -ENODEV; - - /* - * Fall back to the default idle loop, when pm_idle_save had - * been initialized. - */ - if (pm_idle_save) { - pm_idle = pm_idle_save; - /* Relies on interrupts forcing exit from idle. */ - synchronize_sched(); - } - - pr->flags.power = 0; - result = acpi_processor_get_power_info(pr); - if ((pr->flags.power == 1) && (pr->flags.power_setup_done)) - pm_idle = acpi_processor_idle; - - return result; -} - -#ifdef CONFIG_SMP -static void smp_callback(void *v) -{ - /* we already woke the CPU up, nothing more to do */ -} - -/* - * This function gets called when a part of the kernel has a new latency - * requirement. This means we need to get all processors out of their C-state, - * and then recalculate a new suitable C-state. Just do a cross-cpu IPI; that - * wakes them all right up. - */ -static int acpi_processor_latency_notify(struct notifier_block *b, - unsigned long l, void *v) -{ - smp_call_function(smp_callback, NULL, 1); - return NOTIFY_OK; -} - -static struct notifier_block acpi_processor_latency_notifier = { - .notifier_call = acpi_processor_latency_notify, -}; - -#endif - -#else /* CONFIG_CPU_IDLE */ /** * acpi_idle_bm_check - checks if bus master activity was detected @@ -1756,8 +1185,6 @@ int acpi_processor_cst_has_changed(struct acpi_processor *pr) return ret; } -#endif /* CONFIG_CPU_IDLE */ - int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, struct acpi_device *device) { @@ -1786,10 +1213,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, "ACPI: processor limited to max C-state %d\n", max_cstate); first_run++; -#if !defined(CONFIG_CPU_IDLE) && defined(CONFIG_SMP) - pm_qos_add_notifier(PM_QOS_CPU_DMA_LATENCY, - &acpi_processor_latency_notifier); -#endif } if (!pr) @@ -1813,11 +1236,9 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, * platforms that only support C1. */ if (pr->flags.power) { -#ifdef CONFIG_CPU_IDLE acpi_processor_setup_cpuidle(pr); if (cpuidle_register_device(&pr->power.dev)) return -EIO; -#endif printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id); for (i = 1; i <= pr->power.count; i++) @@ -1825,13 +1246,6 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, printk(" C%d[C%d]", i, pr->power.states[i].type); printk(")\n"); - -#ifndef CONFIG_CPU_IDLE - if (pr->id == 0) { - pm_idle_save = pm_idle; - pm_idle = acpi_processor_idle; - } -#endif } /* 'power' [R] */ @@ -1850,34 +1264,12 @@ int acpi_processor_power_exit(struct acpi_processor *pr, if (boot_option_idle_override) return 0; -#ifdef CONFIG_CPU_IDLE cpuidle_unregister_device(&pr->power.dev); -#endif pr->flags.power_setup_done = 0; if (acpi_device_dir(device)) remove_proc_entry(ACPI_PROCESSOR_FILE_POWER, acpi_device_dir(device)); -#ifndef CONFIG_CPU_IDLE - - /* Unregister the idle handler when processor #0 is removed. */ - if (pr->id == 0) { - if (pm_idle_save) - pm_idle = pm_idle_save; - - /* - * We are about to unload the current idle thread pm callback - * (pm_idle), Wait for all processors to update cached/local - * copies of pm_idle before proceeding. - */ - cpu_idle_wait(); -#ifdef CONFIG_SMP - pm_qos_remove_notifier(PM_QOS_CPU_DMA_LATENCY, - &acpi_processor_latency_notifier); -#endif - } -#endif - return 0; } |