1 /*
2 * cpuidle.h - a generic framework for CPU idle power management
3 *
4 * (C) 2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
5 * Shaohua Li <shaohua.li@intel.com>
6 * Adam Belay <abelay@novell.com>
7 *
8 * This code is licenced under the GPL.
9 */
10
11 #ifndef _LINUX_CPUIDLE_H
12 #define _LINUX_CPUIDLE_H
13
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>
19
20 #define CPUIDLE_STATE_MAX 8
21 #define CPUIDLE_NAME_LEN 16
22 #define CPUIDLE_DESC_LEN 32
23
24 struct module;
25
26 struct cpuidle_device;
27 struct cpuidle_driver;
28
29
30 /****************************
31 * CPUIDLE DEVICE INTERFACE *
32 ****************************/
33
34 struct cpuidle_state_usage {
35 void *driver_data;
36
37 unsigned long long usage;
38 unsigned long long time; /* in US */
39 };
40
41 struct cpuidle_state {
42 char name[CPUIDLE_NAME_LEN];
43 char desc[CPUIDLE_DESC_LEN];
44
45 unsigned int flags;
46 unsigned int exit_latency; /* in US */
47 int power_usage; /* in mW */
48 unsigned int target_residency; /* in US */
49 unsigned int disable;
50
51 int (*enter) (struct cpuidle_device *dev,
52 struct cpuidle_driver *drv,
53 int index);
54
55 int (*enter_dead) (struct cpuidle_device *dev, int index);
56 };
57
58 /* Idle State Flags */
59 #define CPUIDLE_FLAG_TIME_VALID (0x01) /* is residency time measurable? */
60 #define CPUIDLE_FLAG_COUPLED (0x02) /* state applies to multiple cpus */
61
62 #define CPUIDLE_DRIVER_FLAGS_MASK (0xFFFF0000)
63
64 /**
65 * cpuidle_get_statedata - retrieves private driver state data
66 * @st_usage: the state usage statistics
67 */
cpuidle_get_statedata(struct cpuidle_state_usage * st_usage)68 static inline void *cpuidle_get_statedata(struct cpuidle_state_usage *st_usage)
69 {
70 return st_usage->driver_data;
71 }
72
73 /**
74 * cpuidle_set_statedata - stores private driver state data
75 * @st_usage: the state usage statistics
76 * @data: the private data
77 */
78 static inline void
cpuidle_set_statedata(struct cpuidle_state_usage * st_usage,void * data)79 cpuidle_set_statedata(struct cpuidle_state_usage *st_usage, void *data)
80 {
81 st_usage->driver_data = data;
82 }
83
84 struct cpuidle_state_kobj {
85 struct cpuidle_state *state;
86 struct cpuidle_state_usage *state_usage;
87 struct completion kobj_unregister;
88 struct kobject kobj;
89 };
90
91 struct cpuidle_device {
92 unsigned int registered:1;
93 unsigned int enabled:1;
94 unsigned int cpu;
95
96 int last_residency;
97 int state_count;
98 struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX];
99 struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
100
101 struct list_head device_list;
102 struct kobject kobj;
103 struct completion kobj_unregister;
104
105 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
106 int safe_state_index;
107 cpumask_t coupled_cpus;
108 struct cpuidle_coupled *coupled;
109 #endif
110 };
111
112 DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
113
114 /**
115 * cpuidle_get_last_residency - retrieves the last state's residency time
116 * @dev: the target CPU
117 *
118 * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
119 */
cpuidle_get_last_residency(struct cpuidle_device * dev)120 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
121 {
122 return dev->last_residency;
123 }
124
125
126 /****************************
127 * CPUIDLE DRIVER INTERFACE *
128 ****************************/
129
130 struct cpuidle_driver {
131 const char *name;
132 struct module *owner;
133
134 unsigned int power_specified:1;
135 /* set to 1 to use the core cpuidle time keeping (for all states). */
136 unsigned int en_core_tk_irqen:1;
137 struct cpuidle_state states[CPUIDLE_STATE_MAX];
138 int state_count;
139 int safe_state_index;
140 };
141
142 #ifdef CONFIG_CPU_IDLE
143 extern void disable_cpuidle(void);
144 extern int cpuidle_idle_call(void);
145 extern int cpuidle_register_driver(struct cpuidle_driver *drv);
146 struct cpuidle_driver *cpuidle_get_driver(void);
147 extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
148 extern int cpuidle_register_device(struct cpuidle_device *dev);
149 extern void cpuidle_unregister_device(struct cpuidle_device *dev);
150
151 extern void cpuidle_pause_and_lock(void);
152 extern void cpuidle_resume_and_unlock(void);
153 extern int cpuidle_enable_device(struct cpuidle_device *dev);
154 extern void cpuidle_disable_device(struct cpuidle_device *dev);
155 extern int cpuidle_wrap_enter(struct cpuidle_device *dev,
156 struct cpuidle_driver *drv, int index,
157 int (*enter)(struct cpuidle_device *dev,
158 struct cpuidle_driver *drv, int index));
159 extern int cpuidle_play_dead(void);
160
161 #else
disable_cpuidle(void)162 static inline void disable_cpuidle(void) { }
cpuidle_idle_call(void)163 static inline int cpuidle_idle_call(void) { return -ENODEV; }
cpuidle_register_driver(struct cpuidle_driver * drv)164 static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
165 {return -ENODEV; }
cpuidle_get_driver(void)166 static inline struct cpuidle_driver *cpuidle_get_driver(void) {return NULL; }
cpuidle_unregister_driver(struct cpuidle_driver * drv)167 static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
cpuidle_register_device(struct cpuidle_device * dev)168 static inline int cpuidle_register_device(struct cpuidle_device *dev)
169 {return -ENODEV; }
cpuidle_unregister_device(struct cpuidle_device * dev)170 static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
171
cpuidle_pause_and_lock(void)172 static inline void cpuidle_pause_and_lock(void) { }
cpuidle_resume_and_unlock(void)173 static inline void cpuidle_resume_and_unlock(void) { }
cpuidle_enable_device(struct cpuidle_device * dev)174 static inline int cpuidle_enable_device(struct cpuidle_device *dev)
175 {return -ENODEV; }
cpuidle_disable_device(struct cpuidle_device * dev)176 static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
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))177 static inline int cpuidle_wrap_enter(struct cpuidle_device *dev,
178 struct cpuidle_driver *drv, int index,
179 int (*enter)(struct cpuidle_device *dev,
180 struct cpuidle_driver *drv, int index))
181 { return -ENODEV; }
cpuidle_play_dead(void)182 static inline int cpuidle_play_dead(void) {return -ENODEV; }
183
184 #endif
185
186 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
187 void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a);
188 #endif
189
190 /******************************
191 * CPUIDLE GOVERNOR INTERFACE *
192 ******************************/
193
194 struct cpuidle_governor {
195 char name[CPUIDLE_NAME_LEN];
196 struct list_head governor_list;
197 unsigned int rating;
198
199 int (*enable) (struct cpuidle_driver *drv,
200 struct cpuidle_device *dev);
201 void (*disable) (struct cpuidle_driver *drv,
202 struct cpuidle_device *dev);
203
204 int (*select) (struct cpuidle_driver *drv,
205 struct cpuidle_device *dev);
206 void (*reflect) (struct cpuidle_device *dev, int index);
207
208 struct module *owner;
209 };
210
211 #ifdef CONFIG_CPU_IDLE
212
213 extern int cpuidle_register_governor(struct cpuidle_governor *gov);
214 extern void cpuidle_unregister_governor(struct cpuidle_governor *gov);
215
216 #ifdef CONFIG_INTEL_IDLE
217 extern int intel_idle_cpu_init(int cpu);
218 #else
intel_idle_cpu_init(int cpu)219 static inline int intel_idle_cpu_init(int cpu) { return -1; }
220 #endif
221
222 #else
intel_idle_cpu_init(int cpu)223 static inline int intel_idle_cpu_init(int cpu) { return -1; }
224
cpuidle_register_governor(struct cpuidle_governor * gov)225 static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
226 {return 0;}
cpuidle_unregister_governor(struct cpuidle_governor * gov)227 static inline void cpuidle_unregister_governor(struct cpuidle_governor *gov) { }
228
229 #endif
230
231 #ifdef CONFIG_ARCH_HAS_CPU_RELAX
232 #define CPUIDLE_DRIVER_STATE_START 1
233 #else
234 #define CPUIDLE_DRIVER_STATE_START 0
235 #endif
236
237 #endif /* _LINUX_CPUIDLE_H */
238