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Diffstat (limited to 'drivers/cpuidle/driver.c')
-rw-r--r--drivers/cpuidle/driver.c67
1 files changed, 51 insertions, 16 deletions
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 6e11701..06dbe7c 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -10,6 +10,7 @@
#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/sched.h>
#include <linux/cpuidle.h>
#include <linux/cpumask.h>
#include <linux/clockchips.h>
@@ -56,7 +57,7 @@ static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv)
}
/**
- * __cpuidle_set_driver - set per CPU driver variables the the given driver.
+ * __cpuidle_set_driver - set per CPU driver variables for the given driver.
* @drv: a valid pointer to a struct cpuidle_driver
*
* For each CPU in the driver's cpumask, unset the registered driver per CPU
@@ -132,7 +133,7 @@ static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv)
* cpuidle_setup_broadcast_timer - enable/disable the broadcast timer
* @arg: a void pointer used to match the SMP cross call API
*
- * @arg is used as a value of type 'long' with on of the two values:
+ * @arg is used as a value of type 'long' with one of the two values:
* - CLOCK_EVT_NOTIFY_BROADCAST_ON
* - CLOCK_EVT_NOTIFY_BROADCAST_OFF
*
@@ -149,10 +150,8 @@ static void cpuidle_setup_broadcast_timer(void *arg)
/**
* __cpuidle_driver_init - initialize the driver's internal data
* @drv: a valid pointer to a struct cpuidle_driver
- *
- * Returns 0 on success, a negative error code otherwise.
*/
-static int __cpuidle_driver_init(struct cpuidle_driver *drv)
+static void __cpuidle_driver_init(struct cpuidle_driver *drv)
{
int i;
@@ -169,20 +168,55 @@ static int __cpuidle_driver_init(struct cpuidle_driver *drv)
/*
* Look for the timer stop flag in the different states, so that we know
* if the broadcast timer has to be set up. The loop is in the reverse
- * order, because usually on of the the deeper states has this flag set.
+ * order, because usually one of the deeper states have this flag set.
*/
for (i = drv->state_count - 1; i >= 0 ; i--) {
+ if (drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP) {
+ drv->bctimer = 1;
+ break;
+ }
+ }
+}
- if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP))
- continue;
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+static int poll_idle(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv, int index)
+{
+ ktime_t t1, t2;
+ s64 diff;
- drv->bctimer = 1;
- break;
- }
+ t1 = ktime_get();
+ local_irq_enable();
+ while (!need_resched())
+ cpu_relax();
- return 0;
+ t2 = ktime_get();
+ diff = ktime_to_us(ktime_sub(t2, t1));
+ if (diff > INT_MAX)
+ diff = INT_MAX;
+
+ dev->last_residency = (int) diff;
+
+ return index;
}
+static void poll_idle_init(struct cpuidle_driver *drv)
+{
+ struct cpuidle_state *state = &drv->states[0];
+
+ snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
+ snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
+ state->exit_latency = 0;
+ state->target_residency = 0;
+ state->power_usage = -1;
+ state->flags = 0;
+ state->enter = poll_idle;
+ state->disabled = false;
+}
+#else
+static void poll_idle_init(struct cpuidle_driver *drv) {}
+#endif /* !CONFIG_ARCH_HAS_CPU_RELAX */
+
/**
* __cpuidle_register_driver: register the driver
* @drv: a valid pointer to a struct cpuidle_driver
@@ -206,9 +240,7 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
if (cpuidle_disabled())
return -ENODEV;
- ret = __cpuidle_driver_init(drv);
- if (ret)
- return ret;
+ __cpuidle_driver_init(drv);
ret = __cpuidle_set_driver(drv);
if (ret)
@@ -218,6 +250,8 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer,
(void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
+ poll_idle_init(drv);
+
return 0;
}
@@ -346,10 +380,11 @@ struct cpuidle_driver *cpuidle_driver_ref(void)
*/
void cpuidle_driver_unref(void)
{
- struct cpuidle_driver *drv = cpuidle_get_driver();
+ struct cpuidle_driver *drv;
spin_lock(&cpuidle_driver_lock);
+ drv = cpuidle_get_driver();
if (drv && !WARN_ON(drv->refcnt <= 0))
drv->refcnt--;
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