summaryrefslogtreecommitdiff
path: root/include/linux/cpuidle.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/cpuidle.h')
-rw-r--r--include/linux/cpuidle.h180
1 files changed, 180 insertions, 0 deletions
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
new file mode 100644
index 000000000000..16a51546db44
--- /dev/null
+++ b/include/linux/cpuidle.h
@@ -0,0 +1,180 @@
+/*
+ * cpuidle.h - a generic framework for CPU idle power management
+ *
+ * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ * Shaohua Li <shaohua.li@intel.com>
+ * Adam Belay <abelay@novell.com>
+ *
+ * This code is licenced under the GPL.
+ */
+
+#ifndef _LINUX_CPUIDLE_H
+#define _LINUX_CPUIDLE_H
+
+#include <linux/percpu.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+#include <linux/completion.h>
+
+#define CPUIDLE_STATE_MAX 8
+#define CPUIDLE_NAME_LEN 16
+
+struct cpuidle_device;
+
+
+/****************************
+ * CPUIDLE DEVICE INTERFACE *
+ ****************************/
+
+struct cpuidle_state {
+ char name[CPUIDLE_NAME_LEN];
+ void *driver_data;
+
+ unsigned int flags;
+ unsigned int exit_latency; /* in US */
+ unsigned int power_usage; /* in mW */
+ unsigned int target_residency; /* in US */
+
+ unsigned int usage;
+ unsigned int time; /* in US */
+
+ int (*enter) (struct cpuidle_device *dev,
+ struct cpuidle_state *state);
+};
+
+/* Idle State Flags */
+#define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
+#define CPUIDLE_FLAG_CHECK_BM (0x02) /* BM activity will exit state */
+#define CPUIDLE_FLAG_SHALLOW (0x10) /* low latency, minimal savings */
+#define CPUIDLE_FLAG_BALANCED (0x20) /* medium latency, moderate savings */
+#define CPUIDLE_FLAG_DEEP (0x40) /* high latency, large savings */
+
+#define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
+
+/**
+ * cpuidle_get_statedata - retrieves private driver state data
+ * @state: the state
+ */
+static inline void * cpuidle_get_statedata(struct cpuidle_state *state)
+{
+ return state->driver_data;
+}
+
+/**
+ * cpuidle_set_statedata - stores private driver state data
+ * @state: the state
+ * @data: the private data
+ */
+static inline void
+cpuidle_set_statedata(struct cpuidle_state *state, void *data)
+{
+ state->driver_data = data;
+}
+
+struct cpuidle_state_kobj {
+ struct cpuidle_state *state;
+ struct completion kobj_unregister;
+ struct kobject kobj;
+};
+
+struct cpuidle_device {
+ int enabled:1;
+ unsigned int cpu;
+
+ int last_residency;
+ int state_count;
+ struct cpuidle_state states[CPUIDLE_STATE_MAX];
+ struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
+ struct cpuidle_state *last_state;
+
+ struct list_head device_list;
+ struct kobject kobj;
+ struct completion kobj_unregister;
+ void *governor_data;
+};
+
+DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
+
+/**
+ * cpuidle_get_last_residency - retrieves the last state's residency time
+ * @dev: the target CPU
+ *
+ * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
+ */
+static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
+{
+ return dev->last_residency;
+}
+
+
+/****************************
+ * CPUIDLE DRIVER INTERFACE *
+ ****************************/
+
+struct cpuidle_driver {
+ char name[CPUIDLE_NAME_LEN];
+ struct module *owner;
+};
+
+#ifdef CONFIG_CPU_IDLE
+
+extern int cpuidle_register_driver(struct cpuidle_driver *drv);
+extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
+extern int cpuidle_register_device(struct cpuidle_device *dev);
+extern void cpuidle_unregister_device(struct cpuidle_device *dev);
+
+extern void cpuidle_pause_and_lock(void);
+extern void cpuidle_resume_and_unlock(void);
+extern int cpuidle_enable_device(struct cpuidle_device *dev);
+extern void cpuidle_disable_device(struct cpuidle_device *dev);
+
+#else
+
+static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
+{return 0;}
+static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
+static inline int cpuidle_register_device(struct cpuidle_device *dev)
+{return 0;}
+static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
+
+static inline void cpuidle_pause_and_lock(void) { }
+static inline void cpuidle_resume_and_unlock(void) { }
+static inline int cpuidle_enable_device(struct cpuidle_device *dev)
+{return 0;}
+static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
+
+#endif
+
+/******************************
+ * CPUIDLE GOVERNOR INTERFACE *
+ ******************************/
+
+struct cpuidle_governor {
+ char name[CPUIDLE_NAME_LEN];
+ struct list_head governor_list;
+ unsigned int rating;
+
+ int (*enable) (struct cpuidle_device *dev);
+ void (*disable) (struct cpuidle_device *dev);
+
+ int (*select) (struct cpuidle_device *dev);
+ void (*reflect) (struct cpuidle_device *dev);
+
+ struct module *owner;
+};
+
+#ifdef CONFIG_CPU_IDLE
+
+extern int cpuidle_register_governor(struct cpuidle_governor *gov);
+extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
+
+#else
+
+static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
+{return 0;}
+static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
+
+#endif
+
+#endif /* _LINUX_CPUIDLE_H */