xref: /linux/drivers/opp/opp.h (revision c8b90d40d5bba8e6fba457b8a7c10d3c0d467e37)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Generic OPP Interface
4  *
5  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
6  *	Nishanth Menon
7  *	Romit Dasgupta
8  *	Kevin Hilman
9  */
10 
11 #ifndef __DRIVER_OPP_H__
12 #define __DRIVER_OPP_H__
13 
14 #include <linux/device.h>
15 #include <linux/interconnect.h>
16 #include <linux/kernel.h>
17 #include <linux/kref.h>
18 #include <linux/list.h>
19 #include <linux/limits.h>
20 #include <linux/pm_opp.h>
21 #include <linux/notifier.h>
22 
23 struct clk;
24 struct regulator;
25 
26 /* Lock to allow exclusive modification to the device and opp lists */
27 extern struct mutex opp_table_lock;
28 
29 extern struct list_head opp_tables;
30 
31 /* OPP Config flags */
32 #define OPP_CONFIG_CLK			BIT(0)
33 #define OPP_CONFIG_REGULATOR		BIT(1)
34 #define OPP_CONFIG_REGULATOR_HELPER	BIT(2)
35 #define OPP_CONFIG_PROP_NAME		BIT(3)
36 #define OPP_CONFIG_SUPPORTED_HW		BIT(4)
37 #define OPP_CONFIG_REQUIRED_DEV		BIT(5)
38 
39 /**
40  * struct opp_config_data - data for set config operations
41  * @opp_table: OPP table
42  * @flags: OPP config flags
43  * @required_dev_index: The position in the array of required_devs
44  *
45  * This structure stores the OPP config information for each OPP table
46  * configuration by the callers.
47  */
48 struct opp_config_data {
49 	struct opp_table *opp_table;
50 	unsigned int flags;
51 	unsigned int required_dev_index;
52 };
53 
54 /**
55  * struct dev_pm_opp_icc_bw - Interconnect bandwidth values
56  * @avg:	Average bandwidth corresponding to this OPP (in icc units)
57  * @peak:	Peak bandwidth corresponding to this OPP (in icc units)
58  *
59  * This structure stores the bandwidth values for a single interconnect path.
60  */
61 struct dev_pm_opp_icc_bw {
62 	u32 avg;
63 	u32 peak;
64 };
65 
66 /*
67  * Internal data structure organization with the OPP layer library is as
68  * follows:
69  * opp_tables (root)
70  *	|- device 1 (represents voltage domain 1)
71  *	|	|- opp 1 (availability, freq, voltage)
72  *	|	|- opp 2 ..
73  *	...	...
74  *	|	`- opp n ..
75  *	|- device 2 (represents the next voltage domain)
76  *	...
77  *	`- device m (represents mth voltage domain)
78  * device 1, 2.. are represented by opp_table structure while each opp
79  * is represented by the opp structure.
80  */
81 
82 /**
83  * struct dev_pm_opp - Generic OPP description structure
84  * @node:	opp table node. The nodes are maintained throughout the lifetime
85  *		of boot. It is expected only an optimal set of OPPs are
86  *		added to the library by the SoC framework.
87  *		IMPORTANT: the opp nodes should be maintained in increasing
88  *		order.
89  * @kref:	for reference count of the OPP.
90  * @available:	true/false - marks if this OPP as available or not
91  * @dynamic:	not-created from static DT entries.
92  * @turbo:	true if turbo (boost) OPP
93  * @suspend:	true if suspend OPP
94  * @removed:	flag indicating that OPP's reference is dropped by OPP core.
95  * @rates:	Frequencies in hertz
96  * @level:	Performance level
97  * @supplies:	Power supplies voltage/current values
98  * @bandwidth:	Interconnect bandwidth values
99  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
100  *		frequency from any other OPP's frequency.
101  * @required_opps: List of OPPs that are required by this OPP.
102  * @opp_table:	points back to the opp_table struct this opp belongs to
103  * @np:		OPP's device node.
104  * @dentry:	debugfs dentry pointer (per opp)
105  *
106  * This structure stores the OPP information for a given device.
107  */
108 struct dev_pm_opp {
109 	struct list_head node;
110 	struct kref kref;
111 
112 	bool available;
113 	bool dynamic;
114 	bool turbo;
115 	bool suspend;
116 	bool removed;
117 	unsigned long *rates;
118 	unsigned int level;
119 
120 	struct dev_pm_opp_supply *supplies;
121 	struct dev_pm_opp_icc_bw *bandwidth;
122 
123 	unsigned long clock_latency_ns;
124 
125 	struct dev_pm_opp **required_opps;
126 	struct opp_table *opp_table;
127 
128 	struct device_node *np;
129 
130 #ifdef CONFIG_DEBUG_FS
131 	struct dentry *dentry;
132 	const char *of_name;
133 #endif
134 };
135 
136 /**
137  * struct opp_device - devices managed by 'struct opp_table'
138  * @node:	list node
139  * @dev:	device to which the struct object belongs
140  * @dentry:	debugfs dentry pointer (per device)
141  *
142  * This is an internal data structure maintaining the devices that are managed
143  * by 'struct opp_table'.
144  */
145 struct opp_device {
146 	struct list_head node;
147 	const struct device *dev;
148 
149 #ifdef CONFIG_DEBUG_FS
150 	struct dentry *dentry;
151 #endif
152 };
153 
154 enum opp_table_access {
155 	OPP_TABLE_ACCESS_UNKNOWN = 0,
156 	OPP_TABLE_ACCESS_EXCLUSIVE = 1,
157 	OPP_TABLE_ACCESS_SHARED = 2,
158 };
159 
160 /**
161  * struct opp_table - Device opp structure
162  * @node:	table node - contains the devices with OPPs that
163  *		have been registered. Nodes once added are not modified in this
164  *		table.
165  * @head:	notifier head to notify the OPP availability changes.
166  * @dev_list:	list of devices that share these OPPs
167  * @opp_list:	table of opps
168  * @kref:	for reference count of the table.
169  * @lock:	mutex protecting the opp_list and dev_list.
170  * @np:		struct device_node pointer for opp's DT node.
171  * @clock_latency_ns_max: Max clock latency in nanoseconds.
172  * @parsed_static_opps: Count of devices for which OPPs are initialized from DT.
173  * @shared_opp: OPP is shared between multiple devices.
174  * @current_rate_single_clk: Currently configured frequency for single clk.
175  * @current_opp: Currently configured OPP for the table.
176  * @suspend_opp: Pointer to OPP to be used during device suspend.
177  * @required_opp_tables: List of device OPP tables that are required by OPPs in
178  *		this table.
179  * @required_devs: List of devices for required OPP tables.
180  * @required_opp_count: Number of required devices.
181  * @supported_hw: Array of version number to support.
182  * @supported_hw_count: Number of elements in supported_hw array.
183  * @prop_name: A name to postfix to many DT properties, while parsing them.
184  * @config_clks: Platform specific config_clks() callback.
185  * @clks: Device's clock handles, for multiple clocks.
186  * @clk: Device's clock handle, for single clock.
187  * @clk_count: Number of clocks.
188  * @config_regulators: Platform specific config_regulators() callback.
189  * @regulators: Supply regulators
190  * @regulator_count: Number of power supply regulators. Its value can be -1
191  * (uninitialized), 0 (no opp-microvolt property) or > 0 (has opp-microvolt
192  * property).
193  * @paths: Interconnect path handles
194  * @path_count: Number of interconnect paths
195  * @enabled: Set to true if the device's resources are enabled/configured.
196  * @is_genpd: Marks if the OPP table belongs to a genpd.
197  * @dentry:	debugfs dentry pointer of the real device directory (not links).
198  * @dentry_name: Name of the real dentry.
199  *
200  * @voltage_tolerance_v1: In percentage, for v1 bindings only.
201  *
202  * This is an internal data structure maintaining the link to opps attached to
203  * a device. This structure is not meant to be shared to users as it is
204  * meant for book keeping and private to OPP library.
205  */
206 struct opp_table {
207 	struct list_head node, lazy;
208 
209 	struct blocking_notifier_head head;
210 	struct list_head dev_list;
211 	struct list_head opp_list;
212 	struct kref kref;
213 	struct mutex lock;
214 
215 	struct device_node *np;
216 	unsigned long clock_latency_ns_max;
217 
218 	/* For backward compatibility with v1 bindings */
219 	unsigned int voltage_tolerance_v1;
220 
221 	unsigned int parsed_static_opps;
222 	enum opp_table_access shared_opp;
223 	unsigned long current_rate_single_clk;
224 	struct dev_pm_opp *current_opp;
225 	struct dev_pm_opp *suspend_opp;
226 
227 	struct opp_table **required_opp_tables;
228 	struct device **required_devs;
229 	unsigned int required_opp_count;
230 
231 	unsigned int *supported_hw;
232 	unsigned int supported_hw_count;
233 	const char *prop_name;
234 	config_clks_t config_clks;
235 	struct clk **clks;
236 	struct clk *clk;
237 	int clk_count;
238 	config_regulators_t config_regulators;
239 	struct regulator **regulators;
240 	int regulator_count;
241 	struct icc_path **paths;
242 	unsigned int path_count;
243 	bool enabled;
244 	bool is_genpd;
245 
246 #ifdef CONFIG_DEBUG_FS
247 	struct dentry *dentry;
248 	char dentry_name[NAME_MAX];
249 #endif
250 };
251 
252 /* Routines internal to opp core */
253 void dev_pm_opp_get(struct dev_pm_opp *opp);
254 bool _opp_remove_all_static(struct opp_table *opp_table);
255 void _get_opp_table_kref(struct opp_table *opp_table);
256 int _get_opp_count(struct opp_table *opp_table);
257 struct opp_table *_find_opp_table(struct device *dev);
258 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
259 struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
260 void _opp_free(struct dev_pm_opp *opp);
261 int _opp_compare_key(struct opp_table *opp_table, struct dev_pm_opp *opp1, struct dev_pm_opp *opp2);
262 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
263 int _opp_add_v1(struct opp_table *opp_table, struct device *dev, struct dev_pm_opp_data *data, bool dynamic);
264 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu);
265 struct opp_table *_add_opp_table_indexed(struct device *dev, int index, bool getclk);
266 void _required_opps_available(struct dev_pm_opp *opp, int count);
267 
268 static inline bool lazy_linking_pending(struct opp_table *opp_table)
269 {
270 	return unlikely(!list_empty(&opp_table->lazy));
271 }
272 
273 #ifdef CONFIG_OF
274 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index);
275 void _of_clear_opp_table(struct opp_table *opp_table);
276 struct opp_table *_managed_opp(struct device *dev, int index);
277 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp);
278 #else
279 static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index) {}
280 static inline void _of_clear_opp_table(struct opp_table *opp_table) {}
281 static inline struct opp_table *_managed_opp(struct device *dev, int index) { return NULL; }
282 static inline void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp) {}
283 #endif
284 
285 #ifdef CONFIG_DEBUG_FS
286 void opp_debug_remove_one(struct dev_pm_opp *opp);
287 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
288 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
289 void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
290 #else
291 static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}
292 
293 static inline void opp_debug_create_one(struct dev_pm_opp *opp,
294 					struct opp_table *opp_table) { }
295 
296 static inline void opp_debug_register(struct opp_device *opp_dev,
297 				      struct opp_table *opp_table) { }
298 
299 static inline void opp_debug_unregister(struct opp_device *opp_dev,
300 					struct opp_table *opp_table)
301 { }
302 #endif		/* DEBUG_FS */
303 
304 #endif		/* __DRIVER_OPP_H__ */
305