/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Generic OPP Interface
 *
 * Copyright (C) 2009-2010 Texas Instruments Incorporated.
 *      Nishanth Menon
 *      Romit Dasgupta
 *      Kevin Hilman
 */

#ifndef __DRIVER_OPP_H__
#define __DRIVER_OPP_H__

#include <linux/device.h>
#include <linux/interconnect.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/limits.h>
#include <linux/pm_opp.h>
#include <linux/notifier.h>

struct clk;
struct regulator;

/* Lock to allow exclusive modification to the device and opp lists */
extern struct mutex opp_table_lock;

extern struct list_head opp_tables, lazy_opp_tables;

/*
 * Internal data structure organization with the OPP layer library is as
 * follows:
 * opp_tables (root)
 *      |- device 1 (represents voltage domain 1)
 *      |       |- opp 1 (availability, freq, voltage)
 *      |       |- opp 2 ..
 *      ...     ...
 *      |       `- opp n ..
 *      |- device 2 (represents the next voltage domain)
 *      ...
 *      `- device m (represents mth voltage domain)
 * device 1, 2.. are represented by opp_table structure while each opp
 * is represented by the opp structure.
 */

/**
 * struct dev_pm_opp - Generic OPP description structure
 * @node:       opp table node. The nodes are maintained throughout the lifetime
 *              of boot. It is expected only an optimal set of OPPs are
 *              added to the library by the SoC framework.
 *              IMPORTANT: the opp nodes should be maintained in increasing
 *              order.
 * @kref:       for reference count of the OPP.
 * @available:  true/false - marks if this OPP as available or not
 * @dynamic:    not-created from static DT entries.
 * @turbo:      true if turbo (boost) OPP
 * @suspend:    true if suspend OPP
 * @removed:    flag indicating that OPP's reference is dropped by OPP core.
 * @pstate: Device's power domain's performance state.
 * @rate:       Frequency in hertz
 * @level:      Performance level
 * @supplies:   Power supplies voltage/current values
 * @bandwidth:  Interconnect bandwidth values
 * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
 *              frequency from any other OPP's frequency.
 * @required_opps: List of OPPs that are required by this OPP.
 * @opp_table:  points back to the opp_table struct this opp belongs to
 * @np:         OPP's device node.
 * @dentry:     debugfs dentry pointer (per opp)
 *
 * This structure stores the OPP information for a given device.
 */
struct dev_pm_opp {
        struct list_head node;
        struct kref kref;

        bool available;
        bool dynamic;
        bool turbo;
        bool suspend;
        bool removed;
        unsigned int pstate;
        unsigned long rate;
        unsigned int level;

        struct dev_pm_opp_supply *supplies;
        struct dev_pm_opp_icc_bw *bandwidth;

        unsigned long clock_latency_ns;

        struct dev_pm_opp **required_opps;
        struct opp_table *opp_table;

        struct device_node *np;

#ifdef CONFIG_DEBUG_FS
        struct dentry *dentry;
#endif
};

/**
 * struct opp_device - devices managed by 'struct opp_table'
 * @node:       list node
 * @dev:        device to which the struct object belongs
 * @dentry:     debugfs dentry pointer (per device)
 *
 * This is an internal data structure maintaining the devices that are managed
 * by 'struct opp_table'.
 */
struct opp_device {
        struct list_head node;
        const struct device *dev;

#ifdef CONFIG_DEBUG_FS
        struct dentry *dentry;
#endif
};

enum opp_table_access {
        OPP_TABLE_ACCESS_UNKNOWN = 0,
        OPP_TABLE_ACCESS_EXCLUSIVE = 1,
        OPP_TABLE_ACCESS_SHARED = 2,
};

/**
 * struct opp_table - Device opp structure
 * @node:       table node - contains the devices with OPPs that
 *              have been registered. Nodes once added are not modified in this
 *              table.
 * @head:       notifier head to notify the OPP availability changes.
 * @dev_list:   list of devices that share these OPPs
 * @opp_list:   table of opps
 * @kref:       for reference count of the table.
 * @lock:       mutex protecting the opp_list and dev_list.
 * @np:         struct device_node pointer for opp's DT node.
 * @clock_latency_ns_max: Max clock latency in nanoseconds.
 * @parsed_static_opps: Count of devices for which OPPs are initialized from DT.
 * @shared_opp: OPP is shared between multiple devices.
 * @current_rate: Currently configured frequency.
 * @current_opp: Currently configured OPP for the table.
 * @suspend_opp: Pointer to OPP to be used during device suspend.
 * @genpd_virt_dev_lock: Mutex protecting the genpd virtual device pointers.
 * @genpd_virt_devs: List of virtual devices for multiple genpd support.
 * @required_opp_tables: List of device OPP tables that are required by OPPs in
 *              this table.
 * @required_opp_count: Number of required devices.
 * @supported_hw: Array of version number to support.
 * @supported_hw_count: Number of elements in supported_hw array.
 * @prop_name: A name to postfix to many DT properties, while parsing them.
 * @clk: Device's clock handle
 * @regulators: Supply regulators
 * @regulator_count: Number of power supply regulators. Its value can be -1
 * (uninitialized), 0 (no opp-microvolt property) or > 0 (has opp-microvolt
 * property).
 * @paths: Interconnect path handles
 * @path_count: Number of interconnect paths
 * @enabled: Set to true if the device's resources are enabled/configured.
 * @genpd_performance_state: Device's power domain support performance state.
 * @is_genpd: Marks if the OPP table belongs to a genpd.
 * @set_opp: Platform specific set_opp callback
 * @sod_supplies: Set opp data supplies
 * @set_opp_data: Data to be passed to set_opp callback
 * @dentry:     debugfs dentry pointer of the real device directory (not links).
 * @dentry_name: Name of the real dentry.
 *
 * @voltage_tolerance_v1: In percentage, for v1 bindings only.
 *
 * This is an internal data structure maintaining the link to opps attached to
 * a device. This structure is not meant to be shared to users as it is
 * meant for book keeping and private to OPP library.
 */
struct opp_table {
        struct list_head node, lazy;

        struct blocking_notifier_head head;
        struct list_head dev_list;
        struct list_head opp_list;
        struct kref kref;
        struct mutex lock;

        struct device_node *np;
        unsigned long clock_latency_ns_max;

        /* For backward compatibility with v1 bindings */
        unsigned int voltage_tolerance_v1;

        unsigned int parsed_static_opps;
        enum opp_table_access shared_opp;
        unsigned long current_rate;
        struct dev_pm_opp *current_opp;
        struct dev_pm_opp *suspend_opp;

        struct mutex genpd_virt_dev_lock;
        struct device **genpd_virt_devs;
        struct opp_table **required_opp_tables;
        unsigned int required_opp_count;

        unsigned int *supported_hw;
        unsigned int supported_hw_count;
        const char *prop_name;
        struct clk *clk;
        struct regulator **regulators;
        int regulator_count;
        struct icc_path **paths;
        unsigned int path_count;
        bool enabled;
        bool genpd_performance_state;
        bool is_genpd;

        int (*set_opp)(struct dev_pm_set_opp_data *data);
        struct dev_pm_opp_supply *sod_supplies;
        struct dev_pm_set_opp_data *set_opp_data;

#ifdef CONFIG_DEBUG_FS
        struct dentry *dentry;
        char dentry_name[NAME_MAX];
#endif
};

/* Routines internal to opp core */
void dev_pm_opp_get(struct dev_pm_opp *opp);
bool _opp_remove_all_static(struct opp_table *opp_table);
void _get_opp_table_kref(struct opp_table *opp_table);
int _get_opp_count(struct opp_table *opp_table);
struct opp_table *_find_opp_table(struct device *dev);
struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
void _opp_free(struct dev_pm_opp *opp);
int _opp_compare_key(struct dev_pm_opp *opp1, struct dev_pm_opp *opp2);
int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table, bool rate_not_available);
int _opp_add_v1(struct opp_table *opp_table, struct device *dev, unsigned long freq, long u_volt, bool dynamic);
void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu);
struct opp_table *_add_opp_table_indexed(struct device *dev, int index, bool getclk);
void _put_opp_list_kref(struct opp_table *opp_table);
void _required_opps_available(struct dev_pm_opp *opp, int count);

static inline bool lazy_linking_pending(struct opp_table *opp_table)
{
        return unlikely(!list_empty(&opp_table->lazy));
}

#ifdef CONFIG_OF
void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index);
void _of_clear_opp_table(struct opp_table *opp_table);
struct opp_table *_managed_opp(struct device *dev, int index);
void _of_opp_free_required_opps(struct opp_table *opp_table,
                                struct dev_pm_opp *opp);
#else
static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index) {}
static inline void _of_clear_opp_table(struct opp_table *opp_table) {}
static inline struct opp_table *_managed_opp(struct device *dev, int index) { return NULL; }
static inline void _of_opp_free_required_opps(struct opp_table *opp_table,
                                              struct dev_pm_opp *opp) {}
#endif

#ifdef CONFIG_DEBUG_FS
void opp_debug_remove_one(struct dev_pm_opp *opp);
void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
#else
static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}

static inline void opp_debug_create_one(struct dev_pm_opp *opp,
                                        struct opp_table *opp_table) { }

static inline void opp_debug_register(struct opp_device *opp_dev,
                                      struct opp_table *opp_table) { }

static inline void opp_debug_unregister(struct opp_device *opp_dev,
                                        struct opp_table *opp_table)
{ }
#endif          /* DEBUG_FS */

#endif          /* __DRIVER_OPP_H__ */