diff options
Diffstat (limited to 'drivers/acpi/processor_idle.c')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 488 |
1 files changed, 449 insertions, 39 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 1f6fb38de01..f996d0e3768 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -40,6 +40,7 @@ #include <linux/sched.h> /* need_resched() */ #include <linux/latency.h> #include <linux/clockchips.h> +#include <linux/cpuidle.h> /* * Include the apic definitions for x86 to have the APIC timer related defines @@ -64,14 +65,22 @@ 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; -module_param(max_cstate, uint, 0644); +#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; +module_param(max_cstate, uint, 0000); 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 @@ -82,9 +91,10 @@ module_param(nocst, uint, 0000); static unsigned int bm_history __read_mostly = (HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1)); module_param(bm_history, uint, 0644); -/* -------------------------------------------------------------------------- - Power Management - -------------------------------------------------------------------------- */ + +static int acpi_processor_set_power_policy(struct acpi_processor *pr); + +#endif /* * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. @@ -177,6 +187,18 @@ static inline u32 ticks_elapsed(u32 t1, u32 t2) return ((0xFFFFFFFF - t1) + t2); } +static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2) +{ + if (t2 >= t1) + return PM_TIMER_TICKS_TO_US(t2 - t1); + else if (!(acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER)) + return PM_TIMER_TICKS_TO_US(((0x00FFFFFF - t1) + t2) & 0x00FFFFFF); + else + return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2); +} + +#ifndef CONFIG_CPU_IDLE + static void acpi_processor_power_activate(struct acpi_processor *pr, struct acpi_processor_cx *new) @@ -248,6 +270,7 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate) unused = inl(acpi_gbl_FADT.xpm_timer_block.address); } } +#endif /* !CONFIG_CPU_IDLE */ #ifdef ARCH_APICTIMER_STOPS_ON_C3 @@ -330,6 +353,7 @@ int acpi_processor_resume(struct acpi_device * device) return 0; } +#ifndef CONFIG_CPU_IDLE static void acpi_processor_idle(void) { struct acpi_processor *pr = NULL; @@ -427,7 +451,7 @@ static void acpi_processor_idle(void) * 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) && + 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 @@ -727,6 +751,7 @@ static int acpi_processor_set_power_policy(struct acpi_processor *pr) return 0; } +#endif /* !CONFIG_CPU_IDLE */ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) { @@ -744,7 +769,7 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) #ifndef CONFIG_HOTPLUG_CPU /* * Check for P_LVL2_UP flag before entering C2 and above on - * an SMP system. + * an SMP system. */ if ((num_online_cpus() > 1) && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) @@ -945,7 +970,12 @@ static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx) * Normalize the C2 latency to expidite policy */ 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; } @@ -1025,7 +1055,12 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr, * use this in our C3 policy */ 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; } @@ -1090,6 +1125,7 @@ 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 * ------------------ @@ -1101,6 +1137,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr) result = acpi_processor_set_power_policy(pr); if (result) return result; +#endif /* * if one state of type C2 or C3 is available, mark this @@ -1117,35 +1154,6 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr) return 0; } -int acpi_processor_cst_has_changed(struct acpi_processor *pr) -{ - int result = 0; - - - if (!pr) - return -EINVAL; - - if (nocst) { - return -ENODEV; - } - - if (!pr->flags.power_setup_done) - return -ENODEV; - - /* Fall back to the default idle loop */ - pm_idle = pm_idle_save; - synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ - - 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; -} - -/* proc interface */ - static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset) { struct acpi_processor *pr = seq->private; @@ -1227,6 +1235,35 @@ 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 (!pr) + return -EINVAL; + + if (nocst) { + return -ENODEV; + } + + if (!pr->flags.power_setup_done) + return -ENODEV; + + /* Fall back to the default idle loop */ + pm_idle = pm_idle_save; + synchronize_sched(); /* Relies on interrupts forcing exit from idle. */ + + 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) { @@ -1249,7 +1286,366 @@ static int acpi_processor_latency_notify(struct notifier_block *b, 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 + */ +static int acpi_idle_bm_check(void) +{ + u32 bm_status = 0; + + acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); + if (bm_status) + 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)) + bm_status = 1; + } + return bm_status; +} + +/** + * acpi_idle_update_bm_rld - updates the BM_RLD bit depending on target state + * @pr: the processor + * @target: the new target state + */ +static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr, + struct acpi_processor_cx *target) +{ + if (pr->flags.bm_rld_set && target->type != ACPI_STATE_C3) { + acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0); + pr->flags.bm_rld_set = 0; + } + + if (!pr->flags.bm_rld_set && target->type == ACPI_STATE_C3) { + acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1); + pr->flags.bm_rld_set = 1; + } +} + +/** + * acpi_idle_do_entry - a helper function that does C2 and C3 type entry + * @cx: cstate data + */ +static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) +{ + if (cx->space_id == ACPI_CSTATE_FFH) { + /* Call into architectural FFH based C-state */ + acpi_processor_ffh_cstate_enter(cx); + } else { + int unused; + /* IO port based C-state */ + inb(cx->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); + } +} + +/** + * acpi_idle_enter_c1 - enters an ACPI C1 state-type + * @dev: the target CPU + * @state: the state data + * + * This is equivalent to the HALT instruction. + */ +static int acpi_idle_enter_c1(struct cpuidle_device *dev, + struct cpuidle_state *state) +{ + struct acpi_processor *pr; + struct acpi_processor_cx *cx = cpuidle_get_statedata(state); + pr = processors[smp_processor_id()]; + + if (unlikely(!pr)) + return 0; + + if (pr->flags.bm_check) + acpi_idle_update_bm_rld(pr, cx); + + current_thread_info()->status &= ~TS_POLLING; + /* + * TS_POLLING-cleared state must be visible before we test + * NEED_RESCHED: + */ + smp_mb(); + if (!need_resched()) + safe_halt(); + current_thread_info()->status |= TS_POLLING; + + cx->usage++; + + return 0; +} + +/** + * acpi_idle_enter_simple - enters an ACPI state without BM handling + * @dev: the target CPU + * @state: the state data + */ +static int acpi_idle_enter_simple(struct cpuidle_device *dev, + struct cpuidle_state *state) +{ + struct acpi_processor *pr; + struct acpi_processor_cx *cx = cpuidle_get_statedata(state); + u32 t1, t2; + pr = processors[smp_processor_id()]; + + if (unlikely(!pr)) + return 0; + + if (acpi_idle_suspend) + return(acpi_idle_enter_c1(dev, state)); + + if (pr->flags.bm_check) + acpi_idle_update_bm_rld(pr, cx); + + local_irq_disable(); + current_thread_info()->status &= ~TS_POLLING; + /* + * TS_POLLING-cleared state must be visible before we test + * NEED_RESCHED: + */ + smp_mb(); + + if (unlikely(need_resched())) { + current_thread_info()->status |= TS_POLLING; + local_irq_enable(); + return 0; + } + + if (cx->type == ACPI_STATE_C3) + ACPI_FLUSH_CPU_CACHE(); + + t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + acpi_state_timer_broadcast(pr, cx, 1); + acpi_idle_do_entry(cx); + t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + +#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC) + /* TSC could halt in idle, so notify users */ + mark_tsc_unstable("TSC halts in idle");; +#endif + + local_irq_enable(); + current_thread_info()->status |= TS_POLLING; + + cx->usage++; + + acpi_state_timer_broadcast(pr, cx, 0); + cx->time += ticks_elapsed(t1, t2); + return ticks_elapsed_in_us(t1, t2); +} + +static int c3_cpu_count; +static DEFINE_SPINLOCK(c3_lock); + +/** + * acpi_idle_enter_bm - enters C3 with proper BM handling + * @dev: the target CPU + * @state: the state data + * + * If BM is detected, the deepest non-C3 idle state is entered instead. + */ +static int acpi_idle_enter_bm(struct cpuidle_device *dev, + struct cpuidle_state *state) +{ + struct acpi_processor *pr; + struct acpi_processor_cx *cx = cpuidle_get_statedata(state); + u32 t1, t2; + pr = processors[smp_processor_id()]; + + if (unlikely(!pr)) + return 0; + + if (acpi_idle_suspend) + return(acpi_idle_enter_c1(dev, state)); + + local_irq_disable(); + current_thread_info()->status &= ~TS_POLLING; + /* + * TS_POLLING-cleared state must be visible before we test + * NEED_RESCHED: + */ + smp_mb(); + + if (unlikely(need_resched())) { + current_thread_info()->status |= TS_POLLING; + local_irq_enable(); + return 0; + } + + /* + * Must be done before busmaster disable as we might need to + * access HPET ! + */ + acpi_state_timer_broadcast(pr, cx, 1); + + if (acpi_idle_bm_check()) { + cx = pr->power.bm_state; + + acpi_idle_update_bm_rld(pr, cx); + + t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + acpi_idle_do_entry(cx); + t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + } else { + acpi_idle_update_bm_rld(pr, cx); + + spin_lock(&c3_lock); + c3_cpu_count++; + /* Disable bus master arbitration when all CPUs are in C3 */ + if (c3_cpu_count == num_online_cpus()) + acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1); + spin_unlock(&c3_lock); + + t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + acpi_idle_do_entry(cx); + t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + + spin_lock(&c3_lock); + /* Re-enable bus master arbitration */ + if (c3_cpu_count == num_online_cpus()) + acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0); + c3_cpu_count--; + spin_unlock(&c3_lock); + } + +#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC) + /* TSC could halt in idle, so notify users */ + mark_tsc_unstable("TSC halts in idle"); +#endif + + local_irq_enable(); + current_thread_info()->status |= TS_POLLING; + + cx->usage++; + + acpi_state_timer_broadcast(pr, cx, 0); + cx->time += ticks_elapsed(t1, t2); + return ticks_elapsed_in_us(t1, t2); +} + +struct cpuidle_driver acpi_idle_driver = { + .name = "acpi_idle", + .owner = THIS_MODULE, +}; + +/** + * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE + * @pr: the ACPI processor + */ +static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) +{ + int i, count = 0; + struct acpi_processor_cx *cx; + struct cpuidle_state *state; + struct cpuidle_device *dev = &pr->power.dev; + + if (!pr->flags.power_setup_done) + return -EINVAL; + + if (pr->flags.power == 0) { + return -EINVAL; + } + + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { + cx = &pr->power.states[i]; + state = &dev->states[count]; + + if (!cx->valid) + continue; + +#ifdef CONFIG_HOTPLUG_CPU + if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) && + !pr->flags.has_cst && + !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) + continue; #endif + cpuidle_set_statedata(state, cx); + + snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); + state->exit_latency = cx->latency; + state->target_residency = cx->latency * 6; + state->power_usage = cx->power; + + state->flags = 0; + switch (cx->type) { + case ACPI_STATE_C1: + state->flags |= CPUIDLE_FLAG_SHALLOW; + state->enter = acpi_idle_enter_c1; + break; + + case ACPI_STATE_C2: + state->flags |= CPUIDLE_FLAG_BALANCED; + state->flags |= CPUIDLE_FLAG_TIME_VALID; + state->enter = acpi_idle_enter_simple; + break; + + case ACPI_STATE_C3: + state->flags |= CPUIDLE_FLAG_DEEP; + state->flags |= CPUIDLE_FLAG_TIME_VALID; + state->flags |= CPUIDLE_FLAG_CHECK_BM; + state->enter = pr->flags.bm_check ? + acpi_idle_enter_bm : + acpi_idle_enter_simple; + break; + } + + count++; + } + + dev->state_count = count; + + if (!count) + return -EINVAL; + + /* find the deepest state that can handle active BM */ + if (pr->flags.bm_check) { + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) + if (pr->power.states[i].type == ACPI_STATE_C3) + break; + pr->power.bm_state = &pr->power.states[i-1]; + } + + return 0; +} + +int acpi_processor_cst_has_changed(struct acpi_processor *pr) +{ + int ret; + + if (!pr) + return -EINVAL; + + if (nocst) { + return -ENODEV; + } + + if (!pr->flags.power_setup_done) + return -ENODEV; + + cpuidle_pause_and_lock(); + cpuidle_disable_device(&pr->power.dev); + acpi_processor_get_power_info(pr); + acpi_processor_setup_cpuidle(pr); + ret = cpuidle_enable_device(&pr->power.dev); + cpuidle_resume_and_unlock(); + + return ret; +} + +#endif /* CONFIG_CPU_IDLE */ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, struct acpi_device *device) @@ -1267,7 +1663,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, "ACPI: processor limited to max C-state %d\n", max_cstate); first_run++; -#ifdef CONFIG_SMP +#if !defined (CONFIG_CPU_IDLE) && defined (CONFIG_SMP) register_latency_notifier(&acpi_processor_latency_notifier); #endif } @@ -1285,6 +1681,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, } acpi_processor_get_power_info(pr); + pr->flags.power_setup_done = 1; /* * Install the idle handler if processor power management is supported. @@ -1292,6 +1689,13 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, * platforms that only support C1. */ if ((pr->flags.power) && (!boot_option_idle_override)) { +#ifdef CONFIG_CPU_IDLE + acpi_processor_setup_cpuidle(pr); + pr->power.dev.cpu = pr->id; + 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++) if (pr->power.states[i].valid) @@ -1299,10 +1703,12 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, 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] */ @@ -1316,21 +1722,24 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr, entry->owner = THIS_MODULE; } - pr->flags.power_setup_done = 1; - return 0; } int acpi_processor_power_exit(struct acpi_processor *pr, struct acpi_device *device) { - +#ifdef CONFIG_CPU_IDLE + if ((pr->flags.power) && (!boot_option_idle_override)) + 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) { pm_idle = pm_idle_save; @@ -1345,6 +1754,7 @@ int acpi_processor_power_exit(struct acpi_processor *pr, unregister_latency_notifier(&acpi_processor_latency_notifier); #endif } +#endif return 0; } |