/* * Generic OPP Interface * * Copyright (C) 2009-2010 Texas Instruments Incorporated. * Nishanth Menon * Romit Dasgupta * Kevin Hilman * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #ifndef __DRIVER_OPP_H__ #define __DRIVER_OPP_H__ #include #include #include #include #include #include #include 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; /* * 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. * RCU usage: opp table is traversed with RCU locks. node * modification is possible realtime, hence the modifications * are protected by the opp_table_lock for integrity. * IMPORTANT: the opp nodes should be maintained in increasing * order. * @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 * @rate: Frequency in hertz * @u_volt: Target voltage in microvolts corresponding to this OPP * @u_volt_min: Minimum voltage in microvolts corresponding to this OPP * @u_volt_max: Maximum voltage in microvolts corresponding to this OPP * @u_amp: Maximum current drawn by the device in microamperes * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's * frequency from any other OPP's frequency. * @opp_table: points back to the opp_table struct this opp belongs to * @rcu_head: RCU callback head used for deferred freeing * @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; bool available; bool dynamic; bool turbo; bool suspend; unsigned long rate; unsigned long u_volt; unsigned long u_volt_min; unsigned long u_volt_max; unsigned long u_amp; unsigned long clock_latency_ns; struct opp_table *opp_table; struct rcu_head rcu_head; 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 * @rcu_head: RCU callback head used for deferred freeing * @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; struct rcu_head rcu_head; #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. * RCU usage: nodes are not modified in the table of opp_table, * however addition is possible and is secured by opp_table_lock * @srcu_head: notifier head to notify the OPP availability changes. * @rcu_head: RCU callback head used for deferred freeing * @dev_list: list of devices that share these OPPs * @opp_list: table of opps * @np: struct device_node pointer for opp's DT node. * @clock_latency_ns_max: Max clock latency in nanoseconds. * @shared_opp: OPP is shared between multiple devices. * @suspend_opp: Pointer to OPP to be used during device suspend. * @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 * @regulator: Supply regulator * @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. * * Because the opp structures can be used from both rcu and srcu readers, we * need to wait for the grace period of both of them before freeing any * resources. And so we have used kfree_rcu() from within call_srcu() handlers. */ struct opp_table { struct list_head node; struct srcu_notifier_head srcu_head; struct rcu_head rcu_head; struct list_head dev_list; struct list_head opp_list; struct device_node *np; unsigned long clock_latency_ns_max; /* For backward compatibility with v1 bindings */ unsigned int voltage_tolerance_v1; enum opp_table_access shared_opp; struct dev_pm_opp *suspend_opp; unsigned int *supported_hw; unsigned int supported_hw_count; const char *prop_name; struct clk *clk; struct regulator *regulator; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; char dentry_name[NAME_MAX]; #endif }; /* Routines internal to opp core */ 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 device_node *_of_get_opp_desc_node(struct device *dev); void _dev_pm_opp_remove_table(struct device *dev, bool remove_all); struct dev_pm_opp *_allocate_opp(struct device *dev, struct opp_table **opp_table); int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table); void _opp_remove(struct opp_table *opp_table, struct dev_pm_opp *opp, bool notify); int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, bool dynamic); void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, bool of); #ifdef CONFIG_OF void _of_init_opp_table(struct opp_table *opp_table, struct device *dev); #else static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev) {} #endif #ifdef CONFIG_DEBUG_FS void opp_debug_remove_one(struct dev_pm_opp *opp); int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table); int 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 int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table) { return 0; } static inline int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table) { return 0; } static inline void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table) { } #endif /* DEBUG_FS */ #endif /* __DRIVER_OPP_H__ */