/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Definitions related to Power Management Quality of Service (PM QoS).
 *
 * Copyright (C) 2020 Intel Corporation
 *
 * Authors:
 *      Mark Gross <mgross@linux.intel.com>
 *      Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 */

#ifndef _LINUX_PM_QOS_H
#define _LINUX_PM_QOS_H

#include <linux/plist.h>
#include <linux/notifier.h>
#include <linux/device.h>

enum pm_qos_flags_status {
        PM_QOS_FLAGS_UNDEFINED = -1,
        PM_QOS_FLAGS_NONE,
        PM_QOS_FLAGS_SOME,
        PM_QOS_FLAGS_ALL,
};

#define PM_QOS_DEFAULT_VALUE    (-1)
#define PM_QOS_LATENCY_ANY      S32_MAX
#define PM_QOS_LATENCY_ANY_NS   ((s64)PM_QOS_LATENCY_ANY * NSEC_PER_USEC)

#define PM_QOS_CPU_LATENCY_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
#define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE     PM_QOS_LATENCY_ANY
#define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT     PM_QOS_LATENCY_ANY
#define PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS  PM_QOS_LATENCY_ANY_NS
#define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE  0
#define PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE      0
#define PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE      FREQ_QOS_MAX_DEFAULT_VALUE
#define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT  (-1)

#define PM_QOS_FLAG_NO_POWER_OFF        (1 << 0)

enum pm_qos_type {
        PM_QOS_UNITIALIZED,
        PM_QOS_MAX,             /* return the largest value */
        PM_QOS_MIN,             /* return the smallest value */
};

/*
 * Note: The lockless read path depends on the CPU accessing target_value
 * or effective_flags atomically.  Atomic access is only guaranteed on all CPU
 * types linux supports for 32 bit quantites
 */
struct pm_qos_constraints {
        struct plist_head list;
        s32 target_value;       /* Do not change to 64 bit */
        s32 default_value;
        s32 no_constraint_value;
        enum pm_qos_type type;
        struct blocking_notifier_head *notifiers;
};

struct pm_qos_request {
        struct plist_node node;
        struct pm_qos_constraints *qos;
};

struct pm_qos_flags_request {
        struct list_head node;
        s32 flags;      /* Do not change to 64 bit */
};

struct pm_qos_flags {
        struct list_head list;
        s32 effective_flags;    /* Do not change to 64 bit */
};


#define FREQ_QOS_MIN_DEFAULT_VALUE      0
#define FREQ_QOS_MAX_DEFAULT_VALUE      S32_MAX

enum freq_qos_req_type {
        FREQ_QOS_MIN = 1,
        FREQ_QOS_MAX,
};

struct freq_constraints {
        struct pm_qos_constraints min_freq;
        struct blocking_notifier_head min_freq_notifiers;
        struct pm_qos_constraints max_freq;
        struct blocking_notifier_head max_freq_notifiers;
};

struct freq_qos_request {
        enum freq_qos_req_type type;
        struct plist_node pnode;
        struct freq_constraints *qos;
};


enum dev_pm_qos_req_type {
        DEV_PM_QOS_RESUME_LATENCY = 1,
        DEV_PM_QOS_LATENCY_TOLERANCE,
        DEV_PM_QOS_MIN_FREQUENCY,
        DEV_PM_QOS_MAX_FREQUENCY,
        DEV_PM_QOS_FLAGS,
};

struct dev_pm_qos_request {
        enum dev_pm_qos_req_type type;
        union {
                struct plist_node pnode;
                struct pm_qos_flags_request flr;
                struct freq_qos_request freq;
        } data;
        struct device *dev;
};

struct dev_pm_qos {
        struct pm_qos_constraints resume_latency;
        struct pm_qos_constraints latency_tolerance;
        struct freq_constraints freq;
        struct pm_qos_flags flags;
        struct dev_pm_qos_request *resume_latency_req;
        struct dev_pm_qos_request *latency_tolerance_req;
        struct dev_pm_qos_request *flags_req;
};

/* Action requested to pm_qos_update_target */
enum pm_qos_req_action {
        PM_QOS_ADD_REQ,         /* Add a new request */
        PM_QOS_UPDATE_REQ,      /* Update an existing request */
        PM_QOS_REMOVE_REQ       /* Remove an existing request */
};

static inline int dev_pm_qos_request_active(struct dev_pm_qos_request *req)
{
        return req->dev != NULL;
}

s32 pm_qos_read_value(struct pm_qos_constraints *c);
int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
                         enum pm_qos_req_action action, int value);
bool pm_qos_update_flags(struct pm_qos_flags *pqf,
                         struct pm_qos_flags_request *req,
                         enum pm_qos_req_action action, s32 val);

#ifdef CONFIG_CPU_IDLE
s32 cpu_latency_qos_limit(void);
bool cpu_latency_qos_request_active(struct pm_qos_request *req);
void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value);
void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value);
void cpu_latency_qos_remove_request(struct pm_qos_request *req);
#else
static inline s32 cpu_latency_qos_limit(void) { return INT_MAX; }
static inline bool cpu_latency_qos_request_active(struct pm_qos_request *req)
{
        return false;
}
static inline void cpu_latency_qos_add_request(struct pm_qos_request *req,
                                               s32 value) {}
static inline void cpu_latency_qos_update_request(struct pm_qos_request *req,
                                                  s32 new_value) {}
static inline void cpu_latency_qos_remove_request(struct pm_qos_request *req) {}
#endif

#ifdef CONFIG_PM_QOS_CPU_SYSTEM_WAKEUP
s32 cpu_wakeup_latency_qos_limit(void);
#else
static inline s32 cpu_wakeup_latency_qos_limit(void)
{
        return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
}
#endif

#ifdef CONFIG_PM
enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask);
enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask);
s32 __dev_pm_qos_resume_latency(struct device *dev);
s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type);
int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
                           enum dev_pm_qos_req_type type, s32 value);
int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value);
int dev_pm_qos_remove_request(struct dev_pm_qos_request *req);
int dev_pm_qos_add_notifier(struct device *dev,
                            struct notifier_block *notifier,
                            enum dev_pm_qos_req_type type);
int dev_pm_qos_remove_notifier(struct device *dev,
                               struct notifier_block *notifier,
                               enum dev_pm_qos_req_type type);
void dev_pm_qos_constraints_init(struct device *dev);
void dev_pm_qos_constraints_destroy(struct device *dev);
int dev_pm_qos_add_ancestor_request(struct device *dev,
                                    struct dev_pm_qos_request *req,
                                    enum dev_pm_qos_req_type type, s32 value);
int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value);
void dev_pm_qos_hide_latency_limit(struct device *dev);
int dev_pm_qos_expose_flags(struct device *dev, s32 value);
void dev_pm_qos_hide_flags(struct device *dev);
int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set);
s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev);
int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val);
int dev_pm_qos_expose_latency_tolerance(struct device *dev);
void dev_pm_qos_hide_latency_tolerance(struct device *dev);

static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
{
        return dev->power.qos->resume_latency_req->data.pnode.prio;
}

static inline s32 dev_pm_qos_requested_flags(struct device *dev)
{
        return dev->power.qos->flags_req->data.flr.flags;
}

static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev)
{
        return IS_ERR_OR_NULL(dev->power.qos) ?
                PM_QOS_RESUME_LATENCY_NO_CONSTRAINT :
                pm_qos_read_value(&dev->power.qos->resume_latency);
}
#else
static inline enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev,
                                                          s32 mask)
                        { return PM_QOS_FLAGS_UNDEFINED; }
static inline enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev,
                                                        s32 mask)
                        { return PM_QOS_FLAGS_UNDEFINED; }
static inline s32 __dev_pm_qos_resume_latency(struct device *dev)
                        { return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; }
static inline s32 dev_pm_qos_read_value(struct device *dev,
                                        enum dev_pm_qos_req_type type)
{
        switch (type) {
        case DEV_PM_QOS_RESUME_LATENCY:
                return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
        case DEV_PM_QOS_MIN_FREQUENCY:
                return PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE;
        case DEV_PM_QOS_MAX_FREQUENCY:
                return PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE;
        default:
                WARN_ON(1);
                return 0;
        }
}

static inline int dev_pm_qos_add_request(struct device *dev,
                                         struct dev_pm_qos_request *req,
                                         enum dev_pm_qos_req_type type,
                                         s32 value)
                        { return 0; }
static inline int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
                                            s32 new_value)
                        { return 0; }
static inline int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
                        { return 0; }
static inline int dev_pm_qos_add_notifier(struct device *dev,
                                          struct notifier_block *notifier,
                                          enum dev_pm_qos_req_type type)
                        { return 0; }
static inline int dev_pm_qos_remove_notifier(struct device *dev,
                                             struct notifier_block *notifier,
                                             enum dev_pm_qos_req_type type)
                        { return 0; }
static inline void dev_pm_qos_constraints_init(struct device *dev)
{
        dev->power.power_state = PMSG_ON;
}
static inline void dev_pm_qos_constraints_destroy(struct device *dev)
{
        dev->power.power_state = PMSG_INVALID;
}
static inline int dev_pm_qos_add_ancestor_request(struct device *dev,
                                                  struct dev_pm_qos_request *req,
                                                  enum dev_pm_qos_req_type type,
                                                  s32 value)
                        { return 0; }
static inline int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value)
                        { return 0; }
static inline void dev_pm_qos_hide_latency_limit(struct device *dev) {}
static inline int dev_pm_qos_expose_flags(struct device *dev, s32 value)
                        { return 0; }
static inline void dev_pm_qos_hide_flags(struct device *dev) {}
static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set)
                        { return 0; }
static inline s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev)
                        { return PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; }
static inline int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val)
                        { return 0; }
static inline int dev_pm_qos_expose_latency_tolerance(struct device *dev)
                        { return 0; }
static inline void dev_pm_qos_hide_latency_tolerance(struct device *dev) {}

static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
{
        return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
}
static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; }
static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev)
{
        return PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
}
#endif

static inline int freq_qos_request_active(struct freq_qos_request *req)
{
        return !IS_ERR_OR_NULL(req->qos);
}

void freq_constraints_init(struct freq_constraints *qos);

s32 freq_qos_read_value(struct freq_constraints *qos,
                        enum freq_qos_req_type type);

int freq_qos_add_request(struct freq_constraints *qos,
                         struct freq_qos_request *req,
                         enum freq_qos_req_type type, s32 value);
int freq_qos_update_request(struct freq_qos_request *req, s32 new_value);
int freq_qos_remove_request(struct freq_qos_request *req);
int freq_qos_apply(struct freq_qos_request *req,
                   enum pm_qos_req_action action, s32 value);

int freq_qos_add_notifier(struct freq_constraints *qos,
                          enum freq_qos_req_type type,
                          struct notifier_block *notifier);
int freq_qos_remove_notifier(struct freq_constraints *qos,
                             enum freq_qos_req_type type,
                             struct notifier_block *notifier);

#endif