drivers/opp/opp.h

   1 /*
   2  * Generic OPP Interface
   3  *
   4  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   5  *      Nishanth Menon
   6  *      Romit Dasgupta
   7  *      Kevin Hilman
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #ifndef __DRIVER_OPP_H__
  15 #define __DRIVER_OPP_H__
  16
  17 #include <linux/device.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kref.h>
  20 #include <linux/list.h>
  21 #include <linux/limits.h>
  22 #include <linux/pm_opp.h>
  23 #include <linux/notifier.h>
  24
  25 struct clk;
  26 struct regulator;
  27
  28 /* Lock to allow exclusive modification to the device and opp lists */
  29 extern struct mutex opp_table_lock;
  30
  31 extern struct list_head opp_tables;
  32
  33 /*
  34  * Internal data structure organization with the OPP layer library is as
  35  * follows:
  36  * opp_tables (root)
  37  *      |- device 1 (represents voltage domain 1)
  38  *      |       |- opp 1 (availability, freq, voltage)
  39  *      |       |- opp 2 ..
  40  *      ...     ...
  41  *      |       `- opp n ..
  42  *      |- device 2 (represents the next voltage domain)
  43  *      ...
  44  *      `- device m (represents mth voltage domain)
  45  * device 1, 2.. are represented by opp_table structure while each opp
  46  * is represented by the opp structure.
  47  */
  48
  49 /**
  50  * struct dev_pm_opp - Generic OPP description structure
  51  * @node:       opp table node. The nodes are maintained throughout the lifetime
  52  *              of boot. It is expected only an optimal set of OPPs are
  53  *              added to the library by the SoC framework.
  54  *              IMPORTANT: the opp nodes should be maintained in increasing
  55  *              order.
  56  * @kref:       for reference count of the OPP.
  57  * @available:  true/false - marks if this OPP as available or not
  58  * @dynamic:    not-created from static DT entries.
  59  * @turbo:      true if turbo (boost) OPP
  60  * @suspend:    true if suspend OPP
  61  * @pstate: Device's power domain's performance state.
  62  * @rate:       Frequency in hertz
  63  * @level:      Performance level
  64  * @supplies:   Power supplies voltage/current values
  65  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
  66  *              frequency from any other OPP's frequency.
  67  * @required_opps: List of OPPs that are required by this OPP.
  68  * @opp_table:  points back to the opp_table struct this opp belongs to
  69  * @np:         OPP's device node.
  70  * @dentry:     debugfs dentry pointer (per opp)
  71  *
  72  * This structure stores the OPP information for a given device.
  73  */
  74 struct dev_pm_opp {
  75         struct list_head node;
  76         struct kref kref;
  77
  78         bool available;
  79         bool dynamic;
  80         bool turbo;
  81         bool suspend;
  82         unsigned int pstate;
  83         unsigned long rate;
  84         unsigned int level;
  85
  86         struct dev_pm_opp_supply *supplies;
  87
  88         unsigned long clock_latency_ns;
  89
  90         struct dev_pm_opp **required_opps;
  91         struct opp_table *opp_table;
  92
  93         struct device_node *np;
  94
  95 #ifdef CONFIG_DEBUG_FS
  96         struct dentry *dentry;
  97 #endif
  98 };
  99
 100 /**
 101  * struct opp_device - devices managed by 'struct opp_table'
 102  * @node:       list node
 103  * @dev:        device to which the struct object belongs
 104  * @dentry:     debugfs dentry pointer (per device)
 105  *
 106  * This is an internal data structure maintaining the devices that are managed
 107  * by 'struct opp_table'.
 108  */
 109 struct opp_device {
 110         struct list_head node;
 111         const struct device *dev;
 112
 113 #ifdef CONFIG_DEBUG_FS
 114         struct dentry *dentry;
 115 #endif
 116 };
 117
 118 enum opp_table_access {
 119         OPP_TABLE_ACCESS_UNKNOWN = 0,
 120         OPP_TABLE_ACCESS_EXCLUSIVE = 1,
 121         OPP_TABLE_ACCESS_SHARED = 2,
 122 };
 123
 124 /**
 125  * struct opp_table - Device opp structure
 126  * @node:       table node - contains the devices with OPPs that
 127  *              have been registered. Nodes once added are not modified in this
 128  *              table.
 129  * @head:       notifier head to notify the OPP availability changes.
 130  * @dev_list:   list of devices that share these OPPs
 131  * @opp_list:   table of opps
 132  * @kref:       for reference count of the table.
 133  * @list_kref:  for reference count of the OPP list.
 134  * @lock:       mutex protecting the opp_list and dev_list.
 135  * @np:         struct device_node pointer for opp's DT node.
 136  * @clock_latency_ns_max: Max clock latency in nanoseconds.
 137  * @parsed_static_opps: True if OPPs are initialized from DT.
 138  * @shared_opp: OPP is shared between multiple devices.
 139  * @suspend_opp: Pointer to OPP to be used during device suspend.
 140  * @genpd_virt_dev_lock: Mutex protecting the genpd virtual device pointers.
 141  * @genpd_virt_devs: List of virtual devices for multiple genpd support.
 142  * @required_opp_tables: List of device OPP tables that are required by OPPs in
 143  *              this table.
 144  * @required_opp_count: Number of required devices.
 145  * @supported_hw: Array of version number to support.
 146  * @supported_hw_count: Number of elements in supported_hw array.
 147  * @prop_name: A name to postfix to many DT properties, while parsing them.
 148  * @clk: Device's clock handle
 149  * @regulators: Supply regulators
 150  * @regulator_count: Number of power supply regulators. Its value can be -1
 151  * (uninitialized), 0 (no opp-microvolt property) or > 0 (has opp-microvolt
 152  * property).
 153  * @genpd_performance_state: Device's power domain support performance state.
 154  * @is_genpd: Marks if the OPP table belongs to a genpd.
 155  * @set_opp: Platform specific set_opp callback
 156  * @set_opp_data: Data to be passed to set_opp callback
 157  * @dentry:     debugfs dentry pointer of the real device directory (not links).
 158  * @dentry_name: Name of the real dentry.
 159  *
 160  * @voltage_tolerance_v1: In percentage, for v1 bindings only.
 161  *
 162  * This is an internal data structure maintaining the link to opps attached to
 163  * a device. This structure is not meant to be shared to users as it is
 164  * meant for book keeping and private to OPP library.
 165  */
 166 struct opp_table {
 167         struct list_head node;
 168
 169         struct blocking_notifier_head head;
 170         struct list_head dev_list;
 171         struct list_head opp_list;
 172         struct kref kref;
 173         struct kref list_kref;
 174         struct mutex lock;
 175
 176         struct device_node *np;
 177         unsigned long clock_latency_ns_max;
 178
 179         /* For backward compatibility with v1 bindings */
 180         unsigned int voltage_tolerance_v1;
 181
 182         bool parsed_static_opps;
 183         enum opp_table_access shared_opp;
 184         struct dev_pm_opp *suspend_opp;
 185
 186         struct mutex genpd_virt_dev_lock;
 187         struct device **genpd_virt_devs;
 188         struct opp_table **required_opp_tables;
 189         unsigned int required_opp_count;
 190
 191         unsigned int *supported_hw;
 192         unsigned int supported_hw_count;
 193         const char *prop_name;
 194         struct clk *clk;
 195         struct regulator **regulators;
 196         int regulator_count;
 197         bool genpd_performance_state;
 198         bool is_genpd;
 199
 200         int (*set_opp)(struct dev_pm_set_opp_data *data);
 201         struct dev_pm_set_opp_data *set_opp_data;
 202
 203 #ifdef CONFIG_DEBUG_FS
 204         struct dentry *dentry;
 205         char dentry_name[NAME_MAX];
 206 #endif
 207 };
 208
 209 /* Routines internal to opp core */
 210 void dev_pm_opp_get(struct dev_pm_opp *opp);
 211 void _opp_remove_all_static(struct opp_table *opp_table);
 212 void _get_opp_table_kref(struct opp_table *opp_table);
 213 int _get_opp_count(struct opp_table *opp_table);
 214 struct opp_table *_find_opp_table(struct device *dev);
 215 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
 216 void _dev_pm_opp_find_and_remove_table(struct device *dev);
 217 struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
 218 void _opp_free(struct dev_pm_opp *opp);
 219 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table, bool rate_not_available);
 220 int _opp_add_v1(struct opp_table *opp_table, struct device *dev, unsigned long freq, long u_volt, bool dynamic);
 221 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu);
 222 struct opp_table *_add_opp_table(struct device *dev);
 223 void _put_opp_list_kref(struct opp_table *opp_table);
 224
 225 #ifdef CONFIG_OF
 226 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index);
 227 void _of_clear_opp_table(struct opp_table *opp_table);
 228 struct opp_table *_managed_opp(struct device *dev, int index);
 229 void _of_opp_free_required_opps(struct opp_table *opp_table,
 230                                 struct dev_pm_opp *opp);
 231 #else
 232 static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index) {}
 233 static inline void _of_clear_opp_table(struct opp_table *opp_table) {}
 234 static inline struct opp_table *_managed_opp(struct device *dev, int index) { return NULL; }
 235 static inline void _of_opp_free_required_opps(struct opp_table *opp_table,
 236                                               struct dev_pm_opp *opp) {}
 237 #endif
 238
 239 #ifdef CONFIG_DEBUG_FS
 240 void opp_debug_remove_one(struct dev_pm_opp *opp);
 241 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
 242 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
 243 void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
 244 #else
 245 static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}
 246
 247 static inline void opp_debug_create_one(struct dev_pm_opp *opp,
 248                                         struct opp_table *opp_table) { }
 249
 250 static inline void opp_debug_register(struct opp_device *opp_dev,
 251                                       struct opp_table *opp_table) { }
 252
 253 static inline void opp_debug_unregister(struct opp_device *opp_dev,
 254                                         struct opp_table *opp_table)
 255 { }
 256 #endif          /* DEBUG_FS */
 257
 258 #endif          /* __DRIVER_OPP_H__ */