xref: /linux-6.15/include/linux/pm_qos.h (revision 5b06eeae)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_PM_QOS_H
3 #define _LINUX_PM_QOS_H
4 /* interface for the pm_qos_power infrastructure of the linux kernel.
5  *
6  * Mark Gross <[email protected]>
7  */
8 #include <linux/plist.h>
9 #include <linux/notifier.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 
17 	/* insert new class ID */
18 	PM_QOS_NUM_CLASSES,
19 };
20 
21 enum pm_qos_flags_status {
22 	PM_QOS_FLAGS_UNDEFINED = -1,
23 	PM_QOS_FLAGS_NONE,
24 	PM_QOS_FLAGS_SOME,
25 	PM_QOS_FLAGS_ALL,
26 };
27 
28 #define PM_QOS_DEFAULT_VALUE	(-1)
29 #define PM_QOS_LATENCY_ANY	S32_MAX
30 #define PM_QOS_LATENCY_ANY_NS	((s64)PM_QOS_LATENCY_ANY * NSEC_PER_USEC)
31 
32 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
33 #define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE	PM_QOS_LATENCY_ANY
34 #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT	PM_QOS_LATENCY_ANY
35 #define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS	PM_QOS_LATENCY_ANY_NS
36 #define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE	0
37 #define PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE	0
38 #define PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE	(-1)
39 #define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT	(-1)
40 
41 #define PM_QOS_FLAG_NO_POWER_OFF	(1 << 0)
42 
43 struct pm_qos_request {
44 	struct plist_node node;
45 	int pm_qos_class;
46 	struct delayed_work work; /* for pm_qos_update_request_timeout */
47 };
48 
49 struct pm_qos_flags_request {
50 	struct list_head node;
51 	s32 flags;	/* Do not change to 64 bit */
52 };
53 
54 enum dev_pm_qos_req_type {
55 	DEV_PM_QOS_RESUME_LATENCY = 1,
56 	DEV_PM_QOS_LATENCY_TOLERANCE,
57 	DEV_PM_QOS_MIN_FREQUENCY,
58 	DEV_PM_QOS_MAX_FREQUENCY,
59 	DEV_PM_QOS_FLAGS,
60 };
61 
62 struct dev_pm_qos_request {
63 	enum dev_pm_qos_req_type type;
64 	union {
65 		struct plist_node pnode;
66 		struct pm_qos_flags_request flr;
67 	} data;
68 	struct device *dev;
69 };
70 
71 enum pm_qos_type {
72 	PM_QOS_UNITIALIZED,
73 	PM_QOS_MAX,		/* return the largest value */
74 	PM_QOS_MIN,		/* return the smallest value */
75 	PM_QOS_SUM		/* return the sum */
76 };
77 
78 /*
79  * Note: The lockless read path depends on the CPU accessing target_value
80  * or effective_flags atomically.  Atomic access is only guaranteed on all CPU
81  * types linux supports for 32 bit quantites
82  */
83 struct pm_qos_constraints {
84 	struct plist_head list;
85 	s32 target_value;	/* Do not change to 64 bit */
86 	s32 default_value;
87 	s32 no_constraint_value;
88 	enum pm_qos_type type;
89 	struct blocking_notifier_head *notifiers;
90 };
91 
92 struct pm_qos_flags {
93 	struct list_head list;
94 	s32 effective_flags;	/* Do not change to 64 bit */
95 };
96 
97 struct dev_pm_qos {
98 	struct pm_qos_constraints resume_latency;
99 	struct pm_qos_constraints latency_tolerance;
100 	struct pm_qos_constraints min_frequency;
101 	struct pm_qos_constraints max_frequency;
102 	struct pm_qos_flags flags;
103 	struct dev_pm_qos_request *resume_latency_req;
104 	struct dev_pm_qos_request *latency_tolerance_req;
105 	struct dev_pm_qos_request *flags_req;
106 	struct dev_pm_qos_request *min_frequency_req;
107 	struct dev_pm_qos_request *max_frequency_req;
108 };
109 
110 /* Action requested to pm_qos_update_target */
111 enum pm_qos_req_action {
112 	PM_QOS_ADD_REQ,		/* Add a new request */
113 	PM_QOS_UPDATE_REQ,	/* Update an existing request */
114 	PM_QOS_REMOVE_REQ	/* Remove an existing request */
115 };
116 
117 static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
118 {
119 	return req->dev != NULL;
120 }
121 
122 int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
123 			 enum pm_qos_req_action action, int value);
124 bool pm_qos_update_flags(struct pm_qos_flags *pqf,
125 			 struct pm_qos_flags_request *req,
126 			 enum pm_qos_req_action action, s32 val);
127 void pm_qos_add_request(struct pm_qos_request *req, int pm_qos_class,
128 			s32 value);
129 void pm_qos_update_request(struct pm_qos_request *req,
130 			   s32 new_value);
131 void pm_qos_update_request_timeout(struct pm_qos_request *req,
132 				   s32 new_value, unsigned long timeout_us);
133 void pm_qos_remove_request(struct pm_qos_request *req);
134 
135 int pm_qos_request(int pm_qos_class);
136 int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier);
137 int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier);
138 int pm_qos_request_active(struct pm_qos_request *req);
139 s32 pm_qos_read_value(struct pm_qos_constraints *c);
140 
141 #ifdef CONFIG_PM
142 enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask);
143 enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask);
144 s32 __dev_pm_qos_resume_latency(struct device *dev);
145 s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type);
146 int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
147 			   enum dev_pm_qos_req_type type, s32 value);
148 int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
149 int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
150 int dev_pm_qos_add_notifier(struct device *dev,
151 			    struct notifier_block *notifier,
152 			    enum dev_pm_qos_req_type type);
153 int dev_pm_qos_remove_notifier(struct device *dev,
154 			       struct notifier_block *notifier,
155 			       enum dev_pm_qos_req_type type);
156 void dev_pm_qos_constraints_init(struct device *dev);
157 void dev_pm_qos_constraints_destroy(struct device *dev);
158 int dev_pm_qos_add_ancestor_request(struct device *dev,
159 				    struct dev_pm_qos_request *req,
160 				    enum dev_pm_qos_req_type type, s32 value);
161 int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value);
162 void dev_pm_qos_hide_latency_limit(struct device *dev);
163 int dev_pm_qos_expose_flags(struct device *dev, s32 value);
164 void dev_pm_qos_hide_flags(struct device *dev);
165 int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set);
166 s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev);
167 int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val);
168 int dev_pm_qos_expose_latency_tolerance(struct device *dev);
169 void dev_pm_qos_hide_latency_tolerance(struct device *dev);
170 
171 static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
172 {
173 	return dev->power.qos->resume_latency_req->data.pnode.prio;
174 }
175 
176 static inline s32 dev_pm_qos_requested_flags(struct device *dev)
177 {
178 	return dev->power.qos->flags_req->data.flr.flags;
179 }
180 
181 static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev)
182 {
183 	return IS_ERR_OR_NULL(dev->power.qos) ?
184 		PM_QOS_RESUME_LATENCY_NO_CONSTRAINT :
185 		pm_qos_read_value(&dev->power.qos->resume_latency);
186 }
187 #else
188 static inline enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev,
189 							  s32 mask)
190 			{ return PM_QOS_FLAGS_UNDEFINED; }
191 static inline enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev,
192 							s32 mask)
193 			{ return PM_QOS_FLAGS_UNDEFINED; }
194 static inline s32 __dev_pm_qos_resume_latency(struct device *dev)
195 			{ return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; }
196 static inline s32 dev_pm_qos_read_value(struct device *dev,
197 					enum dev_pm_qos_req_type type)
198 {
199 	switch (type) {
200 	case DEV_PM_QOS_RESUME_LATENCY:
201 		return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
202 	case DEV_PM_QOS_MIN_FREQUENCY:
203 		return PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE;
204 	case DEV_PM_QOS_MAX_FREQUENCY:
205 		return PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE;
206 	default:
207 		WARN_ON(1);
208 		return 0;
209 	}
210 }
211 
212 static inline int dev_pm_qos_add_request(struct device *dev,
213 					 struct dev_pm_qos_request *req,
214 					 enum dev_pm_qos_req_type type,
215 					 s32 value)
216 			{ return 0; }
217 static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
218 					    s32 new_value)
219 			{ return 0; }
220 static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
221 			{ return 0; }
222 static inline int dev_pm_qos_add_notifier(struct device *dev,
223 					  struct notifier_block *notifier,
224 					  enum dev_pm_qos_req_type type)
225 			{ return 0; }
226 static inline int dev_pm_qos_remove_notifier(struct device *dev,
227 					     struct notifier_block *notifier,
228 					     enum dev_pm_qos_req_type type)
229 			{ return 0; }
230 static inline void dev_pm_qos_constraints_init(struct device *dev)
231 {
232 	dev->power.power_state = PMSG_ON;
233 }
234 static inline void dev_pm_qos_constraints_destroy(struct device *dev)
235 {
236 	dev->power.power_state = PMSG_INVALID;
237 }
238 static inline int dev_pm_qos_add_ancestor_request(struct device *dev,
239 						  struct dev_pm_qos_request *req,
240 						  enum dev_pm_qos_req_type type,
241 						  s32 value)
242 			{ return 0; }
243 static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
244 			{ return 0; }
245 static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {}
246 static inline int dev_pm_qos_expose_flags(struct device *dev, s32 value)
247 			{ return 0; }
248 static inline void dev_pm_qos_hide_flags(struct device *dev) {}
249 static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set)
250 			{ return 0; }
251 static inline s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev)
252 			{ return PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; }
253 static inline int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val)
254 			{ return 0; }
255 static inline int dev_pm_qos_expose_latency_tolerance(struct device *dev)
256 			{ return 0; }
257 static inline void dev_pm_qos_hide_latency_tolerance(struct device *dev) {}
258 
259 static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
260 {
261 	return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
262 }
263 static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; }
264 static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev)
265 {
266 	return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
267 }
268 #endif
269 
270 #endif
271