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/hrtimer.h>
18 #define CPUIDLE_STATE_MAX 10
19 #define CPUIDLE_NAME_LEN 16
20 #define CPUIDLE_DESC_LEN 32
24 struct cpuidle_device
;
25 struct cpuidle_driver
;
28 /****************************
29 * CPUIDLE DEVICE INTERFACE *
30 ****************************/
32 struct cpuidle_state_usage
{
33 unsigned long long disable
;
34 unsigned long long usage
;
35 unsigned long long time
; /* in US */
38 struct cpuidle_state
{
39 char name
[CPUIDLE_NAME_LEN
];
40 char desc
[CPUIDLE_DESC_LEN
];
43 unsigned int exit_latency
; /* in US */
44 int power_usage
; /* in mW */
45 unsigned int target_residency
; /* in US */
46 bool disabled
; /* disabled on all CPUs */
48 int (*enter
) (struct cpuidle_device
*dev
,
49 struct cpuidle_driver
*drv
,
52 int (*enter_dead
) (struct cpuidle_device
*dev
, int index
);
55 /* Idle State Flags */
56 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
57 #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
58 #define CPUIDLE_FLAG_TIMER_STOP (0x04) /* timer is stopped on this state */
60 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
62 struct cpuidle_device_kobj
;
63 struct cpuidle_state_kobj
;
64 struct cpuidle_driver_kobj
;
66 struct cpuidle_device
{
67 unsigned int registered
:1;
68 unsigned int enabled
:1;
73 struct cpuidle_state_usage states_usage
[CPUIDLE_STATE_MAX
];
74 struct cpuidle_state_kobj
*kobjs
[CPUIDLE_STATE_MAX
];
75 struct cpuidle_driver_kobj
*kobj_driver
;
76 struct cpuidle_device_kobj
*kobj_dev
;
77 struct list_head device_list
;
79 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
81 cpumask_t coupled_cpus
;
82 struct cpuidle_coupled
*coupled
;
86 DECLARE_PER_CPU(struct cpuidle_device
*, cpuidle_devices
);
87 DECLARE_PER_CPU(struct cpuidle_device
, cpuidle_dev
);
90 * cpuidle_get_last_residency - retrieves the last state's residency time
91 * @dev: the target CPU
93 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
95 static inline int cpuidle_get_last_residency(struct cpuidle_device
*dev
)
97 return dev
->last_residency
;
101 /****************************
102 * CPUIDLE DRIVER INTERFACE *
103 ****************************/
105 struct cpuidle_driver
{
107 struct module
*owner
;
110 /* used by the cpuidle framework to setup the broadcast timer */
111 unsigned int bctimer
:1;
112 /* states array must be ordered in decreasing power consumption */
113 struct cpuidle_state states
[CPUIDLE_STATE_MAX
];
115 int safe_state_index
;
117 /* the driver handles the cpus in cpumask */
118 struct cpumask
*cpumask
;
121 #ifdef CONFIG_CPU_IDLE
122 extern void disable_cpuidle(void);
124 extern int cpuidle_select(struct cpuidle_driver
*drv
,
125 struct cpuidle_device
*dev
);
126 extern int cpuidle_enter(struct cpuidle_driver
*drv
,
127 struct cpuidle_device
*dev
, int index
);
128 extern void cpuidle_reflect(struct cpuidle_device
*dev
, int index
);
130 extern int cpuidle_register_driver(struct cpuidle_driver
*drv
);
131 extern struct cpuidle_driver
*cpuidle_get_driver(void);
132 extern struct cpuidle_driver
*cpuidle_driver_ref(void);
133 extern void cpuidle_driver_unref(void);
134 extern void cpuidle_unregister_driver(struct cpuidle_driver
*drv
);
135 extern int cpuidle_register_device(struct cpuidle_device
*dev
);
136 extern void cpuidle_unregister_device(struct cpuidle_device
*dev
);
137 extern int cpuidle_register(struct cpuidle_driver
*drv
,
138 const struct cpumask
*const coupled_cpus
);
139 extern void cpuidle_unregister(struct cpuidle_driver
*drv
);
140 extern void cpuidle_pause_and_lock(void);
141 extern void cpuidle_resume_and_unlock(void);
142 extern void cpuidle_pause(void);
143 extern void cpuidle_resume(void);
144 extern int cpuidle_enable_device(struct cpuidle_device
*dev
);
145 extern void cpuidle_disable_device(struct cpuidle_device
*dev
);
146 extern int cpuidle_play_dead(void);
147 extern void cpuidle_use_deepest_state(bool enable
);
149 extern struct cpuidle_driver
*cpuidle_get_cpu_driver(struct cpuidle_device
*dev
);
151 static inline void disable_cpuidle(void) { }
152 static inline int cpuidle_select(struct cpuidle_driver
*drv
,
153 struct cpuidle_device
*dev
)
155 static inline int cpuidle_enter(struct cpuidle_driver
*drv
,
156 struct cpuidle_device
*dev
, int index
)
158 static inline void cpuidle_reflect(struct cpuidle_device
*dev
, int index
) { }
159 static inline int cpuidle_register_driver(struct cpuidle_driver
*drv
)
161 static inline struct cpuidle_driver
*cpuidle_get_driver(void) {return NULL
; }
162 static inline struct cpuidle_driver
*cpuidle_driver_ref(void) {return NULL
; }
163 static inline void cpuidle_driver_unref(void) {}
164 static inline void cpuidle_unregister_driver(struct cpuidle_driver
*drv
) { }
165 static inline int cpuidle_register_device(struct cpuidle_device
*dev
)
167 static inline void cpuidle_unregister_device(struct cpuidle_device
*dev
) { }
168 static inline int cpuidle_register(struct cpuidle_driver
*drv
,
169 const struct cpumask
*const coupled_cpus
)
171 static inline void cpuidle_unregister(struct cpuidle_driver
*drv
) { }
172 static inline void cpuidle_pause_and_lock(void) { }
173 static inline void cpuidle_resume_and_unlock(void) { }
174 static inline void cpuidle_pause(void) { }
175 static inline void cpuidle_resume(void) { }
176 static inline int cpuidle_enable_device(struct cpuidle_device
*dev
)
178 static inline void cpuidle_disable_device(struct cpuidle_device
*dev
) { }
179 static inline int cpuidle_play_dead(void) {return -ENODEV
; }
180 static inline void cpuidle_use_deepest_state(bool enable
) {}
181 static inline struct cpuidle_driver
*cpuidle_get_cpu_driver(
182 struct cpuidle_device
*dev
) {return NULL
; }
185 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
186 void cpuidle_coupled_parallel_barrier(struct cpuidle_device
*dev
, atomic_t
*a
);
188 static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device
*dev
, atomic_t
*a
)
193 /******************************
194 * CPUIDLE GOVERNOR INTERFACE *
195 ******************************/
197 struct cpuidle_governor
{
198 char name
[CPUIDLE_NAME_LEN
];
199 struct list_head governor_list
;
202 int (*enable
) (struct cpuidle_driver
*drv
,
203 struct cpuidle_device
*dev
);
204 void (*disable
) (struct cpuidle_driver
*drv
,
205 struct cpuidle_device
*dev
);
207 int (*select
) (struct cpuidle_driver
*drv
,
208 struct cpuidle_device
*dev
);
209 void (*reflect
) (struct cpuidle_device
*dev
, int index
);
211 struct module
*owner
;
214 #ifdef CONFIG_CPU_IDLE
215 extern int cpuidle_register_governor(struct cpuidle_governor
*gov
);
217 static inline int cpuidle_register_governor(struct cpuidle_governor
*gov
)
221 #ifdef CONFIG_ARCH_HAS_CPU_RELAX
222 #define CPUIDLE_DRIVER_STATE_START 1
224 #define CPUIDLE_DRIVER_STATE_START 0
227 #endif /* _LINUX_CPUIDLE_H */