diff options
-rw-r--r-- | arch/x86/Kconfig | 6 | ||||
-rw-r--r-- | drivers/acpi/processor_idle.c | 47 | ||||
-rw-r--r-- | drivers/cpuidle/Kconfig | 4 | ||||
-rw-r--r-- | drivers/cpuidle/cpuidle.c | 43 | ||||
-rw-r--r-- | include/acpi/processor.h | 3 | ||||
-rw-r--r-- | include/linux/cpuidle.h | 26 |
6 files changed, 111 insertions, 18 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e6728bd61cc1..3954ae96b0c7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -98,6 +98,9 @@ config ARCH_HAS_ILOG2_U32 config ARCH_HAS_ILOG2_U64 def_bool n +config ARCH_HAS_CPU_IDLE_WAIT + def_bool y + config GENERIC_CALIBRATE_DELAY def_bool y @@ -105,6 +108,9 @@ config GENERIC_TIME_VSYSCALL bool default X86_64 +config ARCH_HAS_CPU_RELAX + def_bool y + config HAVE_SETUP_PER_CPU_AREA def_bool X86_64 diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 199ea2146153..32003fdc91e8 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -98,6 +98,9 @@ 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 /* @@ -201,6 +204,10 @@ static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2) return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2); } +/* + * Callers should disable interrupts before the call and enable + * interrupts after return. + */ static void acpi_safe_halt(void) { current_thread_info()->status &= ~TS_POLLING; @@ -261,7 +268,7 @@ static atomic_t c3_cpu_count; /* Common C-state entry for C2, C3, .. */ static void acpi_cstate_enter(struct acpi_processor_cx *cstate) { - if (cstate->space_id == ACPI_CSTATE_FFH) { + if (cstate->entry_method == ACPI_CSTATE_FFH) { /* Call into architectural FFH based C-state */ acpi_processor_ffh_cstate_enter(cstate); } else { @@ -413,6 +420,8 @@ static void acpi_processor_idle(void) pm_idle_save(); else acpi_safe_halt(); + + local_irq_enable(); return; } @@ -521,6 +530,7 @@ static void acpi_processor_idle(void) * skew otherwise. */ sleep_ticks = 0xFFFFFFFF; + local_irq_enable(); break; case ACPI_STATE_C2: @@ -922,20 +932,20 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) cx.address = reg->address; cx.index = current_count + 1; - cx.space_id = ACPI_CSTATE_SYSTEMIO; + cx.entry_method = ACPI_CSTATE_SYSTEMIO; if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { if (acpi_processor_ffh_cstate_probe (pr->id, &cx, reg) == 0) { - cx.space_id = ACPI_CSTATE_FFH; - } else if (cx.type != ACPI_STATE_C1) { + cx.entry_method = ACPI_CSTATE_FFH; + } else if (cx.type == ACPI_STATE_C1) { /* * C1 is a special case where FIXED_HARDWARE * can be handled in non-MWAIT way as well. * In that case, save this _CST entry info. - * That is, we retain space_id of SYSTEM_IO for - * halt based C1. * Otherwise, ignore this info and continue. */ + cx.entry_method = ACPI_CSTATE_HALT; + } else { continue; } } @@ -1369,12 +1379,16 @@ static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr, /** * acpi_idle_do_entry - a helper function that does C2 and C3 type entry * @cx: cstate data + * + * Caller disables interrupt before call and enables interrupt after return. */ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) { - if (cx->space_id == ACPI_CSTATE_FFH) { + if (cx->entry_method == ACPI_CSTATE_FFH) { /* Call into architectural FFH based C-state */ acpi_processor_ffh_cstate_enter(cx); + } else if (cx->entry_method == ACPI_CSTATE_HALT) { + acpi_safe_halt(); } else { int unused; /* IO port based C-state */ @@ -1396,21 +1410,27 @@ static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx) static int acpi_idle_enter_c1(struct cpuidle_device *dev, struct cpuidle_state *state) { + u32 t1, t2; struct acpi_processor *pr; struct acpi_processor_cx *cx = cpuidle_get_statedata(state); + pr = processors[smp_processor_id()]; if (unlikely(!pr)) return 0; + local_irq_disable(); if (pr->flags.bm_check) acpi_idle_update_bm_rld(pr, cx); - acpi_safe_halt(); + t1 = inl(acpi_gbl_FADT.xpm_timer_block.address); + acpi_idle_do_entry(cx); + t2 = inl(acpi_gbl_FADT.xpm_timer_block.address); + local_irq_enable(); cx->usage++; - return 0; + return ticks_elapsed_in_us(t1, t2); } /** @@ -1517,7 +1537,9 @@ static int acpi_idle_enter_bm(struct cpuidle_device *dev, if (dev->safe_state) { return dev->safe_state->enter(dev, dev->safe_state); } else { + local_irq_disable(); acpi_safe_halt(); + local_irq_enable(); return 0; } } @@ -1609,7 +1631,7 @@ struct cpuidle_driver acpi_idle_driver = { */ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) { - int i, count = 0; + int i, count = CPUIDLE_DRIVER_STATE_START; struct acpi_processor_cx *cx; struct cpuidle_state *state; struct cpuidle_device *dev = &pr->power.dev; @@ -1638,13 +1660,14 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); state->exit_latency = cx->latency; - state->target_residency = cx->latency * 6; + state->target_residency = cx->latency * latency_factor; state->power_usage = cx->power; state->flags = 0; switch (cx->type) { case ACPI_STATE_C1: state->flags |= CPUIDLE_FLAG_SHALLOW; + state->flags |= CPUIDLE_FLAG_TIME_VALID; state->enter = acpi_idle_enter_c1; dev->safe_state = state; break; @@ -1667,6 +1690,8 @@ static int acpi_processor_setup_cpuidle(struct acpi_processor *pr) } count++; + if (count == CPUIDLE_STATE_MAX) + break; } dev->state_count = count; diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index 3bed4127d4ad..7dbc4a83c45c 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -1,13 +1,13 @@ config CPU_IDLE bool "CPU idle PM support" + default ACPI help CPU idle is a generic framework for supporting software-controlled idle processor power management. It includes modular cross-platform governors that can be swapped during runtime. - If you're using a mobile platform that supports CPU idle PM (e.g. - an ACPI-capable notebook), you should say Y here. + If you're using an ACPI-enabled platform, you should say Y here. config CPU_IDLE_GOV_LADDER bool diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 2a98d99cbd46..d868d737742f 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -15,6 +15,7 @@ #include <linux/pm_qos_params.h> #include <linux/cpu.h> #include <linux/cpuidle.h> +#include <linux/ktime.h> #include "cpuidle.h" @@ -82,7 +83,7 @@ void cpuidle_uninstall_idle_handler(void) { if (enabled_devices && (pm_idle != pm_idle_old)) { pm_idle = pm_idle_old; - cpu_idle_wait(); + cpuidle_kick_cpus(); } } @@ -180,6 +181,44 @@ void cpuidle_disable_device(struct cpuidle_device *dev) EXPORT_SYMBOL_GPL(cpuidle_disable_device); +#ifdef CONFIG_ARCH_HAS_CPU_RELAX +static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st) +{ + ktime_t t1, t2; + s64 diff; + int ret; + + t1 = ktime_get(); + local_irq_enable(); + while (!need_resched()) + cpu_relax(); + + t2 = ktime_get(); + diff = ktime_to_us(ktime_sub(t2, t1)); + if (diff > INT_MAX) + diff = INT_MAX; + + ret = (int) diff; + return ret; +} + +static void poll_idle_init(struct cpuidle_device *dev) +{ + struct cpuidle_state *state = &dev->states[0]; + + cpuidle_set_statedata(state, NULL); + + snprintf(state->name, CPUIDLE_NAME_LEN, "C0 (poll idle)"); + state->exit_latency = 0; + state->target_residency = 0; + state->power_usage = -1; + state->flags = CPUIDLE_FLAG_POLL | CPUIDLE_FLAG_TIME_VALID; + state->enter = poll_idle; +} +#else +static void poll_idle_init(struct cpuidle_device *dev) {} +#endif /* CONFIG_ARCH_HAS_CPU_RELAX */ + /** * cpuidle_register_device - registers a CPU's idle PM feature * @dev: the cpu @@ -198,6 +237,8 @@ int cpuidle_register_device(struct cpuidle_device *dev) mutex_lock(&cpuidle_lock); + poll_idle_init(dev); + per_cpu(cpuidle_devices, dev->cpu) = dev; list_add(&dev->device_list, &cpuidle_detected_devices); if ((ret = cpuidle_add_sysfs(sys_dev))) { diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 6e253b5b0f3b..f6d7c508917c 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -34,6 +34,7 @@ #define ACPI_CSTATE_SYSTEMIO (0) #define ACPI_CSTATE_FFH (1) +#define ACPI_CSTATE_HALT (2) /* Power Management */ @@ -64,7 +65,7 @@ struct acpi_processor_cx { u8 valid; u8 type; u32 address; - u8 space_id; + u8 entry_method; u8 index; u32 latency; u32 latency_ticks; diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index b0fd85ab9efb..c8eb8c71809e 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -46,9 +46,10 @@ struct cpuidle_state { /* Idle State Flags */ #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */ #define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */ -#define CPUIDLE_FLAG_SHALLOW (0x10) /* low latency, minimal savings */ -#define CPUIDLE_FLAG_BALANCED (0x20) /* medium latency, moderate savings */ -#define CPUIDLE_FLAG_DEEP (0x40) /* high latency, large savings */ +#define CPUIDLE_FLAG_POLL (0x10) /* no latency, no savings */ +#define CPUIDLE_FLAG_SHALLOW (0x20) /* low latency, minimal savings */ +#define CPUIDLE_FLAG_BALANCED (0x40) /* medium latency, moderate savings */ +#define CPUIDLE_FLAG_DEEP (0x80) /* high latency, large savings */ #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000) @@ -72,6 +73,19 @@ cpuidle_set_statedata(struct cpuidle_state *state, void *data) state->driver_data = data; } +#ifdef CONFIG_SMP +#ifdef CONFIG_ARCH_HAS_CPU_IDLE_WAIT +static inline void cpuidle_kick_cpus(void) +{ + cpu_idle_wait(); +} +#else /* !CONFIG_ARCH_HAS_CPU_IDLE_WAIT */ +#error "Arch needs cpu_idle_wait() equivalent here" +#endif /* !CONFIG_ARCH_HAS_CPU_IDLE_WAIT */ +#else /* !CONFIG_SMP */ +static inline void cpuidle_kick_cpus(void) {} +#endif /* !CONFIG_SMP */ + struct cpuidle_state_kobj { struct cpuidle_state *state; struct completion kobj_unregister; @@ -178,4 +192,10 @@ static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { } #endif +#ifdef CONFIG_ARCH_HAS_CPU_RELAX +#define CPUIDLE_DRIVER_STATE_START 1 +#else +#define CPUIDLE_DRIVER_STATE_START 0 +#endif + #endif /* _LINUX_CPUIDLE_H */ |