include/linux/pm_domain.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * pm_domain.h - Definitions and headers related to device power domains.
   4  *
   5  * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
   6  */
   7
   8 #ifndef _LINUX_PM_DOMAIN_H
   9 #define _LINUX_PM_DOMAIN_H
  10
  11 #include <linux/device.h>
  12 #include <linux/ktime.h>
  13 #include <linux/mutex.h>
  14 #include <linux/pm.h>
  15 #include <linux/err.h>
  16 #include <linux/of.h>
  17 #include <linux/notifier.h>
  18 #include <linux/spinlock.h>
  19 #include <linux/cpumask.h>
  20
  21 /*
  22  * Flags to control the behaviour of a genpd.
  23  *
  24  * These flags may be set in the struct generic_pm_domain's flags field by a
  25  * genpd backend driver. The flags must be set before it calls pm_genpd_init(),
  26  * which initializes a genpd.
  27  *
  28  * GENPD_FLAG_PM_CLK:           Instructs genpd to use the PM clk framework,
  29  *                              while powering on/off attached devices.
  30  *
  31  * GENPD_FLAG_IRQ_SAFE:         This informs genpd that its backend callbacks,
  32  *                              ->power_on|off(), doesn't sleep. Hence, these
  33  *                              can be invoked from within atomic context, which
  34  *                              enables genpd to power on/off the PM domain,
  35  *                              even when pm_runtime_is_irq_safe() returns true,
  36  *                              for any of its attached devices. Note that, a
  37  *                              genpd having this flag set, requires its
  38  *                              masterdomains to also have it set.
  39  *
  40  * GENPD_FLAG_ALWAYS_ON:        Instructs genpd to always keep the PM domain
  41  *                              powered on.
  42  *
  43  * GENPD_FLAG_ACTIVE_WAKEUP:    Instructs genpd to keep the PM domain powered
  44  *                              on, in case any of its attached devices is used
  45  *                              in the wakeup path to serve system wakeups.
  46  *
  47  * GENPD_FLAG_CPU_DOMAIN:       Instructs genpd that it should expect to get
  48  *                              devices attached, which may belong to CPUs or
  49  *                              possibly have subdomains with CPUs attached.
  50  *                              This flag enables the genpd backend driver to
  51  *                              deploy idle power management support for CPUs
  52  *                              and groups of CPUs. Note that, the backend
  53  *                              driver must then comply with the so called,
  54  *                              last-man-standing algorithm, for the CPUs in the
  55  *                              PM domain.
  56  *
  57  * GENPD_FLAG_RPM_ALWAYS_ON:    Instructs genpd to always keep the PM domain
  58  *                              powered on except for system suspend.
  59  *
  60  * GENPD_FLAG_MIN_RESIDENCY:    Enable the genpd governor to consider its
  61  *                              components' next wakeup when determining the
  62  *                              optimal idle state.
  63  */
  64 #define GENPD_FLAG_PM_CLK        (1U << 0)
  65 #define GENPD_FLAG_IRQ_SAFE      (1U << 1)
  66 #define GENPD_FLAG_ALWAYS_ON     (1U << 2)
  67 #define GENPD_FLAG_ACTIVE_WAKEUP (1U << 3)
  68 #define GENPD_FLAG_CPU_DOMAIN    (1U << 4)
  69 #define GENPD_FLAG_RPM_ALWAYS_ON (1U << 5)
  70 #define GENPD_FLAG_MIN_RESIDENCY (1U << 6)
  71
  72 enum gpd_status {
  73         GENPD_STATE_ON = 0,     /* PM domain is on */
  74         GENPD_STATE_OFF,        /* PM domain is off */
  75 };
  76
  77 enum genpd_notication {
  78         GENPD_NOTIFY_PRE_OFF = 0,
  79         GENPD_NOTIFY_OFF,
  80         GENPD_NOTIFY_PRE_ON,
  81         GENPD_NOTIFY_ON,
  82 };
  83
  84 struct dev_power_governor {
  85         bool (*power_down_ok)(struct dev_pm_domain *domain);
  86         bool (*suspend_ok)(struct device *dev);
  87 };
  88
  89 struct gpd_dev_ops {
  90         int (*start)(struct device *dev);
  91         int (*stop)(struct device *dev);
  92 };
  93
  94 struct genpd_power_state {
  95         s64 power_off_latency_ns;
  96         s64 power_on_latency_ns;
  97         s64 residency_ns;
  98         u64 usage;
  99         u64 rejected;
 100         struct fwnode_handle *fwnode;
 101         ktime_t idle_time;
 102         void *data;
 103 };
 104
 105 struct genpd_lock_ops;
 106 struct dev_pm_opp;
 107 struct opp_table;
 108
 109 struct generic_pm_domain {
 110         struct device dev;
 111         struct dev_pm_domain domain;    /* PM domain operations */
 112         struct list_head gpd_list_node; /* Node in the global PM domains list */
 113         struct list_head parent_links;  /* Links with PM domain as a parent */
 114         struct list_head child_links;   /* Links with PM domain as a child */
 115         struct list_head dev_list;      /* List of devices */
 116         struct dev_power_governor *gov;
 117         struct work_struct power_off_work;
 118         struct fwnode_handle *provider; /* Identity of the domain provider */
 119         bool has_provider;
 120         const char *name;
 121         atomic_t sd_count;      /* Number of subdomains with power "on" */
 122         enum gpd_status status; /* Current state of the domain */
 123         unsigned int device_count;      /* Number of devices */
 124         unsigned int suspended_count;   /* System suspend device counter */
 125         unsigned int prepared_count;    /* Suspend counter of prepared devices */
 126         unsigned int performance_state; /* Aggregated max performance state */
 127         cpumask_var_t cpus;             /* A cpumask of the attached CPUs */
 128         int (*power_off)(struct generic_pm_domain *domain);
 129         int (*power_on)(struct generic_pm_domain *domain);
 130         struct raw_notifier_head power_notifiers; /* Power on/off notifiers */
 131         struct opp_table *opp_table;    /* OPP table of the genpd */
 132         unsigned int (*opp_to_performance_state)(struct generic_pm_domain *genpd,
 133                                                  struct dev_pm_opp *opp);
 134         int (*set_performance_state)(struct generic_pm_domain *genpd,
 135                                      unsigned int state);
 136         struct gpd_dev_ops dev_ops;
 137         s64 max_off_time_ns;    /* Maximum allowed "suspended" time. */
 138         ktime_t next_wakeup;    /* Maintained by the domain governor */
 139         bool max_off_time_changed;
 140         bool cached_power_down_ok;
 141         bool cached_power_down_state_idx;
 142         int (*attach_dev)(struct generic_pm_domain *domain,
 143                           struct device *dev);
 144         void (*detach_dev)(struct generic_pm_domain *domain,
 145                            struct device *dev);
 146         unsigned int flags;             /* Bit field of configs for genpd */
 147         struct genpd_power_state *states;
 148         void (*free_states)(struct genpd_power_state *states,
 149                             unsigned int state_count);
 150         unsigned int state_count; /* number of states */
 151         unsigned int state_idx; /* state that genpd will go to when off */
 152         ktime_t on_time;
 153         ktime_t accounting_time;
 154         const struct genpd_lock_ops *lock_ops;
 155         union {
 156                 struct mutex mlock;
 157                 struct {
 158                         spinlock_t slock;
 159                         unsigned long lock_flags;
 160                 };
 161         };
 162
 163 };
 164
 165 static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
 166 {
 167         return container_of(pd, struct generic_pm_domain, domain);
 168 }
 169
 170 struct gpd_link {
 171         struct generic_pm_domain *parent;
 172         struct list_head parent_node;
 173         struct generic_pm_domain *child;
 174         struct list_head child_node;
 175
 176         /* Sub-domain's per-master domain performance state */
 177         unsigned int performance_state;
 178         unsigned int prev_performance_state;
 179 };
 180
 181 struct gpd_timing_data {
 182         s64 suspend_latency_ns;
 183         s64 resume_latency_ns;
 184         s64 effective_constraint_ns;
 185         bool constraint_changed;
 186         bool cached_suspend_ok;
 187 };
 188
 189 struct pm_domain_data {
 190         struct list_head list_node;
 191         struct device *dev;
 192 };
 193
 194 struct generic_pm_domain_data {
 195         struct pm_domain_data base;
 196         struct gpd_timing_data td;
 197         struct notifier_block nb;
 198         struct notifier_block *power_nb;
 199         int cpu;
 200         unsigned int performance_state;
 201         ktime_t next_wakeup;
 202         void *data;
 203 };
 204
 205 #ifdef CONFIG_PM_GENERIC_DOMAINS
 206 static inline struct generic_pm_domain_data *to_gpd_data(struct pm_domain_data *pdd)
 207 {
 208         return container_of(pdd, struct generic_pm_domain_data, base);
 209 }
 210
 211 static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev)
 212 {
 213         return to_gpd_data(dev->power.subsys_data->domain_data);
 214 }
 215
 216 int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev);
 217 int pm_genpd_remove_device(struct device *dev);
 218 int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 219                            struct generic_pm_domain *subdomain);
 220 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 221                               struct generic_pm_domain *subdomain);
 222 int pm_genpd_init(struct generic_pm_domain *genpd,
 223                   struct dev_power_governor *gov, bool is_off);
 224 int pm_genpd_remove(struct generic_pm_domain *genpd);
 225 int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state);
 226 int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb);
 227 int dev_pm_genpd_remove_notifier(struct device *dev);
 228 void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next);
 229
 230 extern struct dev_power_governor simple_qos_governor;
 231 extern struct dev_power_governor pm_domain_always_on_gov;
 232 #ifdef CONFIG_CPU_IDLE
 233 extern struct dev_power_governor pm_domain_cpu_gov;
 234 #endif
 235 #else
 236
 237 static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev)
 238 {
 239         return ERR_PTR(-ENOSYS);
 240 }
 241 static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
 242                                       struct device *dev)
 243 {
 244         return -ENOSYS;
 245 }
 246 static inline int pm_genpd_remove_device(struct device *dev)
 247 {
 248         return -ENOSYS;
 249 }
 250 static inline int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 251                                          struct generic_pm_domain *subdomain)
 252 {
 253         return -ENOSYS;
 254 }
 255 static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 256                                             struct generic_pm_domain *subdomain)
 257 {
 258         return -ENOSYS;
 259 }
 260 static inline int pm_genpd_init(struct generic_pm_domain *genpd,
 261                                 struct dev_power_governor *gov, bool is_off)
 262 {
 263         return -ENOSYS;
 264 }
 265 static inline int pm_genpd_remove(struct generic_pm_domain *genpd)
 266 {
 267         return -EOPNOTSUPP;
 268 }
 269
 270 static inline int dev_pm_genpd_set_performance_state(struct device *dev,
 271                                                      unsigned int state)
 272 {
 273         return -EOPNOTSUPP;
 274 }
 275
 276 static inline int dev_pm_genpd_add_notifier(struct device *dev,
 277                                             struct notifier_block *nb)
 278 {
 279         return -EOPNOTSUPP;
 280 }
 281
 282 static inline int dev_pm_genpd_remove_notifier(struct device *dev)
 283 {
 284         return -EOPNOTSUPP;
 285 }
 286
 287 static inline void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next)
 288 { }
 289
 290 #define simple_qos_governor             (*(struct dev_power_governor *)(NULL))
 291 #define pm_domain_always_on_gov         (*(struct dev_power_governor *)(NULL))
 292 #endif
 293
 294 #ifdef CONFIG_PM_GENERIC_DOMAINS_SLEEP
 295 void dev_pm_genpd_suspend(struct device *dev);
 296 void dev_pm_genpd_resume(struct device *dev);
 297 #else
 298 static inline void dev_pm_genpd_suspend(struct device *dev) {}
 299 static inline void dev_pm_genpd_resume(struct device *dev) {}
 300 #endif
 301
 302 /* OF PM domain providers */
 303 struct of_device_id;
 304
 305 typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args,
 306                                                    void *data);
 307
 308 struct genpd_onecell_data {
 309         struct generic_pm_domain **domains;
 310         unsigned int num_domains;
 311         genpd_xlate_t xlate;
 312 };
 313
 314 #ifdef CONFIG_PM_GENERIC_DOMAINS_OF
 315 int of_genpd_add_provider_simple(struct device_node *np,
 316                                  struct generic_pm_domain *genpd);
 317 int of_genpd_add_provider_onecell(struct device_node *np,
 318                                   struct genpd_onecell_data *data);
 319 void of_genpd_del_provider(struct device_node *np);
 320 int of_genpd_add_device(struct of_phandle_args *args, struct device *dev);
 321 int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
 322                            struct of_phandle_args *subdomain_spec);
 323 int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
 324                               struct of_phandle_args *subdomain_spec);
 325 struct generic_pm_domain *of_genpd_remove_last(struct device_node *np);
 326 int of_genpd_parse_idle_states(struct device_node *dn,
 327                                struct genpd_power_state **states, int *n);
 328 unsigned int pm_genpd_opp_to_performance_state(struct device *genpd_dev,
 329                                                struct dev_pm_opp *opp);
 330
 331 int genpd_dev_pm_attach(struct device *dev);
 332 struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 333                                          unsigned int index);
 334 struct device *genpd_dev_pm_attach_by_name(struct device *dev,
 335                                            const char *name);
 336 #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */
 337 static inline int of_genpd_add_provider_simple(struct device_node *np,
 338                                         struct generic_pm_domain *genpd)
 339 {
 340         return -EOPNOTSUPP;
 341 }
 342
 343 static inline int of_genpd_add_provider_onecell(struct device_node *np,
 344                                         struct genpd_onecell_data *data)
 345 {
 346         return -EOPNOTSUPP;
 347 }
 348
 349 static inline void of_genpd_del_provider(struct device_node *np) {}
 350
 351 static inline int of_genpd_add_device(struct of_phandle_args *args,
 352                                       struct device *dev)
 353 {
 354         return -ENODEV;
 355 }
 356
 357 static inline int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
 358                                          struct of_phandle_args *subdomain_spec)
 359 {
 360         return -ENODEV;
 361 }
 362
 363 static inline int of_genpd_remove_subdomain(struct of_phandle_args *parent_spec,
 364                                         struct of_phandle_args *subdomain_spec)
 365 {
 366         return -ENODEV;
 367 }
 368
 369 static inline int of_genpd_parse_idle_states(struct device_node *dn,
 370                         struct genpd_power_state **states, int *n)
 371 {
 372         return -ENODEV;
 373 }
 374
 375 static inline unsigned int
 376 pm_genpd_opp_to_performance_state(struct device *genpd_dev,
 377                                   struct dev_pm_opp *opp)
 378 {
 379         return 0;
 380 }
 381
 382 static inline int genpd_dev_pm_attach(struct device *dev)
 383 {
 384         return 0;
 385 }
 386
 387 static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 388                                                        unsigned int index)
 389 {
 390         return NULL;
 391 }
 392
 393 static inline struct device *genpd_dev_pm_attach_by_name(struct device *dev,
 394                                                          const char *name)
 395 {
 396         return NULL;
 397 }
 398
 399 static inline
 400 struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
 401 {
 402         return ERR_PTR(-EOPNOTSUPP);
 403 }
 404 #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
 405
 406 #ifdef CONFIG_PM
 407 int dev_pm_domain_attach(struct device *dev, bool power_on);
 408 struct device *dev_pm_domain_attach_by_id(struct device *dev,
 409                                           unsigned int index);
 410 struct device *dev_pm_domain_attach_by_name(struct device *dev,
 411                                             const char *name);
 412 void dev_pm_domain_detach(struct device *dev, bool power_off);
 413 int dev_pm_domain_start(struct device *dev);
 414 void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd);
 415 #else
 416 static inline int dev_pm_domain_attach(struct device *dev, bool power_on)
 417 {
 418         return 0;
 419 }
 420 static inline struct device *dev_pm_domain_attach_by_id(struct device *dev,
 421                                                         unsigned int index)
 422 {
 423         return NULL;
 424 }
 425 static inline struct device *dev_pm_domain_attach_by_name(struct device *dev,
 426                                                           const char *name)
 427 {
 428         return NULL;
 429 }
 430 static inline void dev_pm_domain_detach(struct device *dev, bool power_off) {}
 431 static inline int dev_pm_domain_start(struct device *dev)
 432 {
 433         return 0;
 434 }
 435 static inline void dev_pm_domain_set(struct device *dev,
 436                                      struct dev_pm_domain *pd) {}
 437 #endif
 438
 439 #endif /* _LINUX_PM_DOMAIN_H */