diff options
Diffstat (limited to 'drivers/idle/intel_idle.c')
| -rw-r--r-- | drivers/idle/intel_idle.c | 67 |
1 files changed, 62 insertions, 5 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 56ac09d6c930..d14585b2e045 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -59,6 +59,8 @@ #include <linux/hrtimer.h> /* ktime_get_real() */ #include <trace/events/power.h> #include <linux/sched.h> +#include <linux/notifier.h> +#include <linux/cpu.h> #include <asm/mwait.h> #define INTEL_IDLE_VERSION "0.4" @@ -73,6 +75,7 @@ static int max_cstate = MWAIT_MAX_NUM_CSTATES - 1; static unsigned int mwait_substates; +#define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ @@ -82,6 +85,14 @@ static int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state); static struct cpuidle_state *cpuidle_state_table; /* + * Set this flag for states where the HW flushes the TLB for us + * and so we don't need cross-calls to keep it consistent. + * If this flag is set, SW flushes the TLB, so even if the + * HW doesn't do the flushing, this flag is safe to use. + */ +#define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 + +/* * States are indexed by the cstate number, * which is also the index into the MWAIT hint array. * Thus C0 is a dummy. @@ -122,7 +133,7 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { .driver_data = (void *) 0x00, .flags = CPUIDLE_FLAG_TIME_VALID, .exit_latency = 1, - .target_residency = 4, + .target_residency = 1, .enter = &intel_idle }, { /* MWAIT C2 */ .name = "SNB-C3", @@ -130,7 +141,7 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { .driver_data = (void *) 0x10, .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 80, - .target_residency = 160, + .target_residency = 211, .enter = &intel_idle }, { /* MWAIT C3 */ .name = "SNB-C6", @@ -138,7 +149,7 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { .driver_data = (void *) 0x20, .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 104, - .target_residency = 208, + .target_residency = 345, .enter = &intel_idle }, { /* MWAIT C4 */ .name = "SNB-C7", @@ -146,7 +157,7 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { .driver_data = (void *) 0x30, .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, .exit_latency = 109, - .target_residency = 300, + .target_residency = 345, .enter = &intel_idle }, }; @@ -243,6 +254,39 @@ static int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state) return usec_delta; } +static void __setup_broadcast_timer(void *arg) +{ + unsigned long reason = (unsigned long)arg; + int cpu = smp_processor_id(); + + reason = reason ? + CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; + + clockevents_notify(reason, &cpu); +} + +static int __cpuinit setup_broadcast_cpuhp_notify(struct notifier_block *n, + unsigned long action, void *hcpu) +{ + int hotcpu = (unsigned long)hcpu; + + switch (action & 0xf) { + case CPU_ONLINE: + smp_call_function_single(hotcpu, __setup_broadcast_timer, + (void *)true, 1); + break; + case CPU_DOWN_PREPARE: + smp_call_function_single(hotcpu, __setup_broadcast_timer, + (void *)false, 1); + break; + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata setup_broadcast_notifier = { + .notifier_call = setup_broadcast_cpuhp_notify, +}; + /* * intel_idle_probe() */ @@ -305,7 +349,11 @@ static int intel_idle_probe(void) } if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ - lapic_timer_reliable_states = 0xFFFFFFFF; + lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; + else { + smp_call_function(__setup_broadcast_timer, (void *)true, 1); + register_cpu_notifier(&setup_broadcast_notifier); + } pr_debug(PREFIX "v" INTEL_IDLE_VERSION " model 0x%X\n", boot_cpu_data.x86_model); @@ -403,6 +451,10 @@ static int __init intel_idle_init(void) { int retval; + /* Do not load intel_idle at all for now if idle= is passed */ + if (boot_option_idle_override != IDLE_NO_OVERRIDE) + return -ENODEV; + retval = intel_idle_probe(); if (retval) return retval; @@ -428,6 +480,11 @@ static void __exit intel_idle_exit(void) intel_idle_cpuidle_devices_uninit(); cpuidle_unregister_driver(&intel_idle_driver); + if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) { + smp_call_function(__setup_broadcast_timer, (void *)false, 1); + unregister_cpu_notifier(&setup_broadcast_notifier); + } + return; } |