diff options
Diffstat (limited to 'drivers/cpuidle/cpuidle.c')
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 48 |
1 files changed, 46 insertions, 2 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 794962d9f48b..d868d737742f 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -12,9 +12,10 @@ #include <linux/mutex.h> #include <linux/sched.h> #include <linux/notifier.h> -#include <linux/latency.h> +#include <linux/pm_qos_params.h> #include <linux/cpu.h> #include <linux/cpuidle.h> +#include <linux/ktime.h> #include "cpuidle.h" @@ -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))) { @@ -265,7 +306,10 @@ static struct notifier_block cpuidle_latency_notifier = { .notifier_call = cpuidle_latency_notify, }; -#define latency_notifier_init(x) do { register_latency_notifier(x); } while (0) +static inline void latency_notifier_init(struct notifier_block *n) +{ + pm_qos_add_notifier(PM_QOS_CPU_DMA_LATENCY, n); +} #else /* CONFIG_SMP */ |