2 * cpuidle.h - a generic framework for CPU idle power management
4 * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
8 * This code is licenced under the GPL.
11 #ifndef _LINUX_CPUIDLE_H
12 #define _LINUX_CPUIDLE_H
14 #include <linux/percpu.h>
15 #include <linux/list.h>
16 #include <linux/kobject.h>
17 #include <linux/completion.h>
18 #include <linux/hrtimer.h>
20 #define CPUIDLE_STATE_MAX 8
21 #define CPUIDLE_NAME_LEN 16
22 #define CPUIDLE_DESC_LEN 32
26 struct cpuidle_device
;
27 struct cpuidle_driver
;
30 /****************************
31 * CPUIDLE DEVICE INTERFACE *
32 ****************************/
34 struct cpuidle_state_usage
{
37 unsigned long long disable
;
38 unsigned long long usage
;
39 unsigned long long time
; /* in US */
42 struct cpuidle_state
{
43 char name
[CPUIDLE_NAME_LEN
];
44 char desc
[CPUIDLE_DESC_LEN
];
47 unsigned int exit_latency
; /* in US */
48 int power_usage
; /* in mW */
49 unsigned int target_residency
; /* in US */
50 bool disabled
; /* disabled on all CPUs */
52 int (*enter
) (struct cpuidle_device
*dev
,
53 struct cpuidle_driver
*drv
,
56 int (*enter_dead
) (struct cpuidle_device
*dev
, int index
);
59 /* Idle State Flags */
60 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
61 #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
63 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
66 * cpuidle_get_statedata - retrieves private driver state data
67 * @st_usage: the state usage statistics
69 static inline void *cpuidle_get_statedata(struct cpuidle_state_usage
*st_usage
)
71 return st_usage
->driver_data
;
75 * cpuidle_set_statedata - stores private driver state data
76 * @st_usage: the state usage statistics
77 * @data: the private data
80 cpuidle_set_statedata(struct cpuidle_state_usage
*st_usage
, void *data
)
82 st_usage
->driver_data
= data
;
85 struct cpuidle_device
{
86 unsigned int registered
:1;
87 unsigned int enabled
:1;
92 struct cpuidle_state_usage states_usage
[CPUIDLE_STATE_MAX
];
93 struct cpuidle_state_kobj
*kobjs
[CPUIDLE_STATE_MAX
];
94 struct cpuidle_driver_kobj
*kobj_driver
;
95 struct list_head device_list
;
97 struct completion kobj_unregister
;
99 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
100 int safe_state_index
;
101 cpumask_t coupled_cpus
;
102 struct cpuidle_coupled
*coupled
;
106 DECLARE_PER_CPU(struct cpuidle_device
*, cpuidle_devices
);
109 * cpuidle_get_last_residency - retrieves the last state's residency time
110 * @dev: the target CPU
112 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
114 static inline int cpuidle_get_last_residency(struct cpuidle_device
*dev
)
116 return dev
->last_residency
;
120 /****************************
121 * CPUIDLE DRIVER INTERFACE *
122 ****************************/
124 struct cpuidle_driver
{
126 struct module
*owner
;
129 unsigned int power_specified
:1;
130 /* set to 1 to use the core cpuidle time keeping (for all states). */
131 unsigned int en_core_tk_irqen
:1;
132 struct cpuidle_state states
[CPUIDLE_STATE_MAX
];
134 int safe_state_index
;
137 #ifdef CONFIG_CPU_IDLE
138 extern void disable_cpuidle(void);
139 extern int cpuidle_idle_call(void);
140 extern int cpuidle_register_driver(struct cpuidle_driver
*drv
);
141 extern struct cpuidle_driver
*cpuidle_get_driver(void);
142 extern struct cpuidle_driver
*cpuidle_driver_ref(void);
143 extern void cpuidle_driver_unref(void);
144 extern void cpuidle_unregister_driver(struct cpuidle_driver
*drv
);
145 extern int cpuidle_register_device(struct cpuidle_device
*dev
);
146 extern void cpuidle_unregister_device(struct cpuidle_device
*dev
);
148 extern void cpuidle_pause_and_lock(void);
149 extern void cpuidle_resume_and_unlock(void);
150 extern void cpuidle_pause(void);
151 extern void cpuidle_resume(void);
152 extern int cpuidle_enable_device(struct cpuidle_device
*dev
);
153 extern void cpuidle_disable_device(struct cpuidle_device
*dev
);
154 extern int cpuidle_wrap_enter(struct cpuidle_device
*dev
,
155 struct cpuidle_driver
*drv
, int index
,
156 int (*enter
)(struct cpuidle_device
*dev
,
157 struct cpuidle_driver
*drv
, int index
));
158 extern int cpuidle_play_dead(void);
160 extern struct cpuidle_driver
*cpuidle_get_cpu_driver(struct cpuidle_device
*dev
);
161 extern int cpuidle_register_cpu_driver(struct cpuidle_driver
*drv
, int cpu
);
162 extern void cpuidle_unregister_cpu_driver(struct cpuidle_driver
*drv
, int cpu
);
165 static inline void disable_cpuidle(void) { }
166 static inline int cpuidle_idle_call(void) { return -ENODEV
; }
167 static inline int cpuidle_register_driver(struct cpuidle_driver
*drv
)
169 static inline struct cpuidle_driver
*cpuidle_get_driver(void) {return NULL
; }
170 static inline struct cpuidle_driver
*cpuidle_driver_ref(void) {return NULL
; }
171 static inline void cpuidle_driver_unref(void) {}
172 static inline void cpuidle_unregister_driver(struct cpuidle_driver
*drv
) { }
173 static inline int cpuidle_register_device(struct cpuidle_device
*dev
)
175 static inline void cpuidle_unregister_device(struct cpuidle_device
*dev
) { }
177 static inline void cpuidle_pause_and_lock(void) { }
178 static inline void cpuidle_resume_and_unlock(void) { }
179 static inline void cpuidle_pause(void) { }
180 static inline void cpuidle_resume(void) { }
181 static inline int cpuidle_enable_device(struct cpuidle_device
*dev
)
183 static inline void cpuidle_disable_device(struct cpuidle_device
*dev
) { }
184 static inline int cpuidle_wrap_enter(struct cpuidle_device
*dev
,
185 struct cpuidle_driver
*drv
, int index
,
186 int (*enter
)(struct cpuidle_device
*dev
,
187 struct cpuidle_driver
*drv
, int index
))
189 static inline int cpuidle_play_dead(void) {return -ENODEV
; }
192 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
193 void cpuidle_coupled_parallel_barrier(struct cpuidle_device
*dev
, atomic_t
*a
);
195 static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device
*dev
, atomic_t
*a
)
200 /******************************
201 * CPUIDLE GOVERNOR INTERFACE *
202 ******************************/
204 struct cpuidle_governor
{
205 char name
[CPUIDLE_NAME_LEN
];
206 struct list_head governor_list
;
209 int (*enable
) (struct cpuidle_driver
*drv
,
210 struct cpuidle_device
*dev
);
211 void (*disable
) (struct cpuidle_driver
*drv
,
212 struct cpuidle_device
*dev
);
214 int (*select
) (struct cpuidle_driver
*drv
,
215 struct cpuidle_device
*dev
);
216 void (*reflect
) (struct cpuidle_device
*dev
, int index
);
218 struct module
*owner
;
221 #ifdef CONFIG_CPU_IDLE
223 extern int cpuidle_register_governor(struct cpuidle_governor
*gov
);
224 extern void cpuidle_unregister_governor(struct cpuidle_governor
*gov
);
228 static inline int cpuidle_register_governor(struct cpuidle_governor
*gov
)
230 static inline void cpuidle_unregister_governor(struct cpuidle_governor
*gov
) { }
234 #ifdef CONFIG_ARCH_HAS_CPU_RELAX
235 #define CPUIDLE_DRIVER_STATE_START 1
237 #define CPUIDLE_DRIVER_STATE_START 0
240 #endif /* _LINUX_CPUIDLE_H */