4 files changed, 135 insertions, 11 deletions

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 6588f43017bd..87411cebc577 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -53,6 +53,52 @@ static void cpuidle_kick_cpus(void) {}
 
 static int __cpuidle_register_device(struct cpuidle_device *dev);
 
+static inline int cpuidle_enter(struct cpuidle_device *dev,
+                                struct cpuidle_driver *drv, int index)
+{
+        struct cpuidle_state *target_state = &drv->states[index];
+        return target_state->enter(dev, drv, index);
+}
+
+static inline int cpuidle_enter_tk(struct cpuidle_device *dev,
+                               struct cpuidle_driver *drv, int index)
+{
+        return cpuidle_wrap_enter(dev, drv, index, cpuidle_enter);
+}
+
+typedef int (*cpuidle_enter_t)(struct cpuidle_device *dev,
+                               struct cpuidle_driver *drv, int index);
+
+static cpuidle_enter_t cpuidle_enter_ops;
+
+/**
+ * cpuidle_play_dead - cpu off-lining
+ *
+ * Only returns in case of an error
+ */
+int cpuidle_play_dead(void)
+{
+        struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
+        struct cpuidle_driver *drv = cpuidle_get_driver();
+        int i, dead_state = -1;
+        int power_usage = -1;
+
+        /* Find lowest-power state that supports long-term idle */
+        for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+                struct cpuidle_state *s = &drv->states[i];
+
+                if (s->power_usage < power_usage && s->enter_dead) {
+                        power_usage = s->power_usage;
+                        dead_state = i;
+                }
+        }
+
+        if (dead_state != -1)
+                return drv->states[dead_state].enter_dead(dev, dead_state);
+
+        return -ENODEV;
+}
+
 /**
  * cpuidle_idle_call - the main idle loop
  *
@@ -63,7 +109,6 @@ int cpuidle_idle_call(void)
 {
         struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
         struct cpuidle_driver *drv = cpuidle_get_driver();
-        struct cpuidle_state *target_state;
         int next_state, entered_state;
 
         if (off)
@@ -92,12 +137,10 @@ int cpuidle_idle_call(void)
                 return 0;
         }
 
-        target_state = &drv->states[next_state];
-
         trace_power_start_rcuidle(POWER_CSTATE, next_state, dev->cpu);
         trace_cpu_idle_rcuidle(next_state, dev->cpu);
 
-        entered_state = target_state->enter(dev, drv, next_state);
+        entered_state = cpuidle_enter_ops(dev, drv, next_state);
 
         trace_power_end_rcuidle(dev->cpu);
         trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
@@ -110,6 +153,8 @@ int cpuidle_idle_call(void)
                 dev->states_usage[entered_state].time +=
                                 (unsigned long long)dev->last_residency;
                 dev->states_usage[entered_state].usage++;
+        } else {
+                dev->last_residency = 0;
         }
 
         /* give the governor an opportunity to reflect on the outcome */
@@ -164,6 +209,37 @@ void cpuidle_resume_and_unlock(void)
 
 EXPORT_SYMBOL_GPL(cpuidle_resume_and_unlock);
 
+/**
+ * cpuidle_wrap_enter - performs timekeeping and irqen around enter function
+ * @dev: pointer to a valid cpuidle_device object
+ * @drv: pointer to a valid cpuidle_driver object
+ * @index: index of the target cpuidle state.
+ */
+int cpuidle_wrap_enter(struct cpuidle_device *dev,
+                                struct cpuidle_driver *drv, int index,
+                                int (*enter)(struct cpuidle_device *dev,
+                                        struct cpuidle_driver *drv, int index))
+{
+        ktime_t time_start, time_end;
+        s64 diff;
+
+        time_start = ktime_get();
+
+        index = enter(dev, drv, index);
+
+        time_end = ktime_get();
+
+        local_irq_enable();
+
+        diff = ktime_to_us(ktime_sub(time_end, time_start));
+        if (diff > INT_MAX)
+                diff = INT_MAX;
+
+        dev->last_residency = (int) diff;
+
+        return index;
+}
+
 #ifdef CONFIG_ARCH_HAS_CPU_RELAX
 static int poll_idle(struct cpuidle_device *dev,
                 struct cpuidle_driver *drv, int index)
@@ -197,6 +273,7 @@ static void poll_idle_init(struct cpuidle_driver *drv)
         state->power_usage = -1;
         state->flags = 0;
         state->enter = poll_idle;
+        state->disable = 0;
 }
 #else
 static void poll_idle_init(struct cpuidle_driver *drv) {}
@@ -212,13 +289,14 @@ static void poll_idle_init(struct cpuidle_driver *drv) {}
 int cpuidle_enable_device(struct cpuidle_device *dev)
 {
         int ret, i;
+        struct cpuidle_driver *drv = cpuidle_get_driver();
 
         if (dev->enabled)
                 return 0;
-        if (!cpuidle_get_driver() || !cpuidle_curr_governor)
+        if (!drv || !cpuidle_curr_governor)
                 return -EIO;
         if (!dev->state_count)
-                return -EINVAL;
+                dev->state_count = drv->state_count;
 
         if (dev->registered == 0) {
                 ret = __cpuidle_register_device(dev);
@@ -226,13 +304,16 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
                         return ret;
         }
 
-        poll_idle_init(cpuidle_get_driver());
+        cpuidle_enter_ops = drv->en_core_tk_irqen ?
+                cpuidle_enter_tk : cpuidle_enter;
+
+        poll_idle_init(drv);
 
         if ((ret = cpuidle_add_state_sysfs(dev)))
                 return ret;
 
         if (cpuidle_curr_governor->enable &&
-            (ret = cpuidle_curr_governor->enable(cpuidle_get_driver(), dev)))
+            (ret = cpuidle_curr_governor->enable(drv, dev)))
                 goto fail_sysfs;
 
         for (i = 0; i < dev->state_count; i++) {
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 284d7af5a9c8..40cd3f3024df 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -47,7 +47,7 @@ static void __cpuidle_register_driver(struct cpuidle_driver *drv)
  */
 int cpuidle_register_driver(struct cpuidle_driver *drv)
 {
-        if (!drv)
+        if (!drv || !drv->state_count)
                 return -EINVAL;
 
         if (cpuidle_disabled())
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index ad0952601ae2..06335756ea14 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -236,7 +236,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
 {
         struct menu_device *data = &__get_cpu_var(menu_devices);
         int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY);
-        unsigned int power_usage = -1;
+        int power_usage = -1;
         int i;
         int multiplier;
         struct timespec t;
@@ -280,7 +280,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
          * We want to default to C1 (hlt), not to busy polling
          * unless the timer is happening really really soon.
          */
-        if (data->expected_us > 5)
+        if (data->expected_us > 5 &&
+                drv->states[CPUIDLE_DRIVER_STATE_START].disable == 0)
                 data->last_state_idx = CPUIDLE_DRIVER_STATE_START;
 
         /*
@@ -290,6 +291,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
         for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
                 struct cpuidle_state *s = &drv->states[i];
 
+                if (s->disable)
+                        continue;
                 if (s->target_residency > data->predicted_us)
                         continue;
                 if (s->exit_latency > latency_req)
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
index 3fe41fe4851a..88032b4dc6d2 100644
--- a/drivers/cpuidle/sysfs.c
+++ b/drivers/cpuidle/sysfs.c
@@ -11,6 +11,7 @@
 #include <linux/sysfs.h>
 #include <linux/slab.h>
 #include <linux/cpu.h>
+#include <linux/capability.h>
 
 #include "cpuidle.h"
 
@@ -222,6 +223,9 @@ struct cpuidle_state_attr {
 #define define_one_state_ro(_name, show) \
 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
 
+#define define_one_state_rw(_name, show, store) \
+static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store)
+
 #define define_show_state_function(_name) \
 static ssize_t show_state_##_name(struct cpuidle_state *state, \
                          struct cpuidle_state_usage *state_usage, char *buf) \
@@ -229,6 +233,24 @@ static ssize_t show_state_##_name(struct cpuidle_state *state, \
         return sprintf(buf, "%u\n", state->_name);\
 }
 
+#define define_store_state_function(_name) \
+static ssize_t store_state_##_name(struct cpuidle_state *state, \
+                const char *buf, size_t size) \
+{ \
+        long value; \
+        int err; \
+        if (!capable(CAP_SYS_ADMIN)) \
+                return -EPERM; \
+        err = kstrtol(buf, 0, &value); \
+        if (err) \
+                return err; \
+        if (value) \
+                state->disable = 1; \
+        else \
+                state->disable = 0; \
+        return size; \
+}
+
 #define define_show_state_ull_function(_name) \
 static ssize_t show_state_##_name(struct cpuidle_state *state, \
                         struct cpuidle_state_usage *state_usage, char *buf) \
@@ -251,6 +273,8 @@ define_show_state_ull_function(usage)
 define_show_state_ull_function(time)
 define_show_state_str_function(name)
 define_show_state_str_function(desc)
+define_show_state_function(disable)
+define_store_state_function(disable)
 
 define_one_state_ro(name, show_state_name);
 define_one_state_ro(desc, show_state_desc);
@@ -258,6 +282,7 @@ define_one_state_ro(latency, show_state_exit_latency);
 define_one_state_ro(power, show_state_power_usage);
 define_one_state_ro(usage, show_state_usage);
 define_one_state_ro(time, show_state_time);
+define_one_state_rw(disable, show_state_disable, store_state_disable);
 
 static struct attribute *cpuidle_state_default_attrs[] = {
         &attr_name.attr,
@@ -266,6 +291,7 @@ static struct attribute *cpuidle_state_default_attrs[] = {
         &attr_power.attr,
         &attr_usage.attr,
         &attr_time.attr,
+        &attr_disable.attr,
         NULL
 };
 
@@ -287,8 +313,22 @@ static ssize_t cpuidle_state_show(struct kobject * kobj,
         return ret;
 }
 
+static ssize_t cpuidle_state_store(struct kobject *kobj,
+        struct attribute *attr, const char *buf, size_t size)
+{
+        int ret = -EIO;
+        struct cpuidle_state *state = kobj_to_state(kobj);
+        struct cpuidle_state_attr *cattr = attr_to_stateattr(attr);
+
+        if (cattr->store)
+                ret = cattr->store(state, buf, size);
+
+        return ret;
+}
+
 static const struct sysfs_ops cpuidle_state_sysfs_ops = {
         .show = cpuidle_state_show,
+        .store = cpuidle_state_store,
 };
 
 static void cpuidle_state_sysfs_release(struct kobject *kobj)