xref: /linux-6.15/include/linux/pm_qos.h (revision 8fdff1dc)
1 #ifndef _LINUX_PM_QOS_H
2 #define _LINUX_PM_QOS_H
3 /* interface for the pm_qos_power infrastructure of the linux kernel.
4  *
5  * Mark Gross <[email protected]>
6  */
7 #include <linux/plist.h>
8 #include <linux/notifier.h>
9 #include <linux/miscdevice.h>
10 #include <linux/device.h>
11 #include <linux/workqueue.h>
12 
13 enum {
14 	PM_QOS_RESERVED = 0,
15 	PM_QOS_CPU_DMA_LATENCY,
16 	PM_QOS_NETWORK_LATENCY,
17 	PM_QOS_NETWORK_THROUGHPUT,
18 
19 	/* insert new class ID */
20 	PM_QOS_NUM_CLASSES,
21 };
22 
23 enum pm_qos_flags_status {
24 	PM_QOS_FLAGS_UNDEFINED = -1,
25 	PM_QOS_FLAGS_NONE,
26 	PM_QOS_FLAGS_SOME,
27 	PM_QOS_FLAGS_ALL,
28 };
29 
30 #define PM_QOS_DEFAULT_VALUE -1
31 
32 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
33 #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
34 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
35 #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
36 
37 #define PM_QOS_FLAG_NO_POWER_OFF	(1 << 0)
38 #define PM_QOS_FLAG_REMOTE_WAKEUP	(1 << 1)
39 
40 struct pm_qos_request {
41 	struct plist_node node;
42 	int pm_qos_class;
43 	struct delayed_work work; /* for pm_qos_update_request_timeout */
44 };
45 
46 struct pm_qos_flags_request {
47 	struct list_head node;
48 	s32 flags;	/* Do not change to 64 bit */
49 };
50 
51 enum dev_pm_qos_req_type {
52 	DEV_PM_QOS_LATENCY = 1,
53 	DEV_PM_QOS_FLAGS,
54 };
55 
56 struct dev_pm_qos_request {
57 	enum dev_pm_qos_req_type type;
58 	union {
59 		struct plist_node pnode;
60 		struct pm_qos_flags_request flr;
61 	} data;
62 	struct device *dev;
63 };
64 
65 enum pm_qos_type {
66 	PM_QOS_UNITIALIZED,
67 	PM_QOS_MAX,		/* return the largest value */
68 	PM_QOS_MIN		/* return the smallest value */
69 };
70 
71 /*
72  * Note: The lockless read path depends on the CPU accessing target_value
73  * or effective_flags atomically.  Atomic access is only guaranteed on all CPU
74  * types linux supports for 32 bit quantites
75  */
76 struct pm_qos_constraints {
77 	struct plist_head list;
78 	s32 target_value;	/* Do not change to 64 bit */
79 	s32 default_value;
80 	enum pm_qos_type type;
81 	struct blocking_notifier_head *notifiers;
82 };
83 
84 struct pm_qos_flags {
85 	struct list_head list;
86 	s32 effective_flags;	/* Do not change to 64 bit */
87 };
88 
89 struct dev_pm_qos {
90 	struct pm_qos_constraints latency;
91 	struct pm_qos_flags flags;
92 	struct dev_pm_qos_request *latency_req;
93 	struct dev_pm_qos_request *flags_req;
94 };
95 
96 /* Action requested to pm_qos_update_target */
97 enum pm_qos_req_action {
98 	PM_QOS_ADD_REQ,		/* Add a new request */
99 	PM_QOS_UPDATE_REQ,	/* Update an existing request */
100 	PM_QOS_REMOVE_REQ	/* Remove an existing request */
101 };
102 
103 static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
104 {
105 	return req->dev != NULL;
106 }
107 
108 int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
109 			 enum pm_qos_req_action action, int value);
110 bool pm_qos_update_flags(struct pm_qos_flags *pqf,
111 			 struct pm_qos_flags_request *req,
112 			 enum pm_qos_req_action action, s32 val);
113 void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
114 			s32 value);
115 void pm_qos_update_request(struct pm_qos_request *req,
116 			   s32 new_value);
117 void pm_qos_update_request_timeout(struct pm_qos_request *req,
118 				   s32 new_value, unsigned long timeout_us);
119 void pm_qos_remove_request(struct pm_qos_request *req);
120 
121 int pm_qos_request(int pm_qos_class);
122 int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier);
123 int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier);
124 int pm_qos_request_active(struct pm_qos_request *req);
125 s32 pm_qos_read_value(struct pm_qos_constraints *c);
126 
127 #ifdef CONFIG_PM
128 enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask);
129 enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask);
130 s32 __dev_pm_qos_read_value(struct device *dev);
131 s32 dev_pm_qos_read_value(struct device *dev);
132 int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
133 			   enum dev_pm_qos_req_type type, s32 value);
134 int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
135 int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
136 int dev_pm_qos_add_notifier(struct device *dev,
137 			    struct notifier_block *notifier);
138 int dev_pm_qos_remove_notifier(struct device *dev,
139 			       struct notifier_block *notifier);
140 int dev_pm_qos_add_global_notifier(struct notifier_block *notifier);
141 int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier);
142 void dev_pm_qos_constraints_init(struct device *dev);
143 void dev_pm_qos_constraints_destroy(struct device *dev);
144 int dev_pm_qos_add_ancestor_request(struct device *dev,
145 				    struct dev_pm_qos_request *req, s32 value);
146 #else
147 static inline enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev,
148 							  s32 mask)
149 			{ return PM_QOS_FLAGS_UNDEFINED; }
150 static inline enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev,
151 							s32 mask)
152 			{ return PM_QOS_FLAGS_UNDEFINED; }
153 static inline s32 __dev_pm_qos_read_value(struct device *dev)
154 			{ return 0; }
155 static inline s32 dev_pm_qos_read_value(struct device *dev)
156 			{ return 0; }
157 static inline int dev_pm_qos_add_request(struct device *dev,
158 					 struct dev_pm_qos_request *req,
159 					 enum dev_pm_qos_req_type type,
160 					 s32 value)
161 			{ return 0; }
162 static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
163 					    s32 new_value)
164 			{ return 0; }
165 static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
166 			{ return 0; }
167 static inline int dev_pm_qos_add_notifier(struct device *dev,
168 					  struct notifier_block *notifier)
169 			{ return 0; }
170 static inline int dev_pm_qos_remove_notifier(struct device *dev,
171 					     struct notifier_block *notifier)
172 			{ return 0; }
173 static inline int dev_pm_qos_add_global_notifier(
174 					struct notifier_block *notifier)
175 			{ return 0; }
176 static inline int dev_pm_qos_remove_global_notifier(
177 					struct notifier_block *notifier)
178 			{ return 0; }
179 static inline void dev_pm_qos_constraints_init(struct device *dev)
180 {
181 	dev->power.power_state = PMSG_ON;
182 }
183 static inline void dev_pm_qos_constraints_destroy(struct device *dev)
184 {
185 	dev->power.power_state = PMSG_INVALID;
186 }
187 static inline int dev_pm_qos_add_ancestor_request(struct device *dev,
188 				    struct dev_pm_qos_request *req, s32 value)
189 			{ return 0; }
190 #endif
191 
192 #ifdef CONFIG_PM_RUNTIME
193 int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value);
194 void dev_pm_qos_hide_latency_limit(struct device *dev);
195 int dev_pm_qos_expose_flags(struct device *dev, s32 value);
196 void dev_pm_qos_hide_flags(struct device *dev);
197 int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set);
198 
199 static inline s32 dev_pm_qos_requested_latency(struct device *dev)
200 {
201 	return dev->power.qos->latency_req->data.pnode.prio;
202 }
203 
204 static inline s32 dev_pm_qos_requested_flags(struct device *dev)
205 {
206 	return dev->power.qos->flags_req->data.flr.flags;
207 }
208 #else
209 static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
210 			{ return 0; }
211 static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {}
212 static inline int dev_pm_qos_expose_flags(struct device *dev, s32 value)
213 			{ return 0; }
214 static inline void dev_pm_qos_hide_flags(struct device *dev) {}
215 static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set)
216 			{ return 0; }
217 
218 static inline s32 dev_pm_qos_requested_latency(struct device *dev) { return 0; }
219 static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; }
220 #endif
221 
222 #endif
223