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-rw-r--r--drivers/cpuidle/Kconfig4
-rw-r--r--drivers/cpuidle/cpuidle.c43
2 files changed, 44 insertions, 3 deletions
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))) {
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