1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/*
* 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 <linux/device.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/limits.h>
#include <linux/pm_opp.h>
#include <linux/rculist.h>
#include <linux/rcupdate.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;
/*
* 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
* @supplies: Power supplies voltage/current values
* @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;
struct dev_pm_opp_supply *supplies;
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
* @kref: for reference count of the table.
* @lock: mutex protecting the opp_list.
* @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
* @regulators: Supply regulators
* @regulator_count: Number of power supply regulators
* @set_opp: Platform specific set_opp callback
* @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.
*
* 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 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;
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 **regulators;
unsigned int regulator_count;
int (*set_opp)(struct dev_pm_set_opp_data *data);
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 _get_opp_table_kref(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);
void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev, bool remove_all);
void _dev_pm_opp_find_and_remove_table(struct device *dev, bool remove_all);
struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
void _opp_free(struct dev_pm_opp *opp);
int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
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, bool of);
struct opp_table *_add_opp_table(struct device *dev);
#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__ */
|