xref: /linux/drivers/opp/opp.h (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
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_GENPD		BIT(5)
38 #define OPP_CONFIG_REQUIRED_DEVS	BIT(6)
39 
40 /**
41  * struct opp_config_data - data for set config operations
42  * @opp_table: OPP table
43  * @flags: OPP config flags
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 };
52 
53 /**
54  * struct dev_pm_opp_icc_bw - Interconnect bandwidth values
55  * @avg:	Average bandwidth corresponding to this OPP (in icc units)
56  * @peak:	Peak bandwidth corresponding to this OPP (in icc units)
57  *
58  * This structure stores the bandwidth values for a single interconnect path.
59  */
60 struct dev_pm_opp_icc_bw {
61 	u32 avg;
62 	u32 peak;
63 };
64 
65 /*
66  * Internal data structure organization with the OPP layer library is as
67  * follows:
68  * opp_tables (root)
69  *	|- device 1 (represents voltage domain 1)
70  *	|	|- opp 1 (availability, freq, voltage)
71  *	|	|- opp 2 ..
72  *	...	...
73  *	|	`- opp n ..
74  *	|- device 2 (represents the next voltage domain)
75  *	...
76  *	`- device m (represents mth voltage domain)
77  * device 1, 2.. are represented by opp_table structure while each opp
78  * is represented by the opp structure.
79  */
80 
81 /**
82  * struct dev_pm_opp - Generic OPP description structure
83  * @node:	opp table node. The nodes are maintained throughout the lifetime
84  *		of boot. It is expected only an optimal set of OPPs are
85  *		added to the library by the SoC framework.
86  *		IMPORTANT: the opp nodes should be maintained in increasing
87  *		order.
88  * @kref:	for reference count of the OPP.
89  * @available:	true/false - marks if this OPP as available or not
90  * @dynamic:	not-created from static DT entries.
91  * @turbo:	true if turbo (boost) OPP
92  * @suspend:	true if suspend OPP
93  * @removed:	flag indicating that OPP's reference is dropped by OPP core.
94  * @rates:	Frequencies in hertz
95  * @level:	Performance level
96  * @supplies:	Power supplies voltage/current values
97  * @bandwidth:	Interconnect bandwidth values
98  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
99  *		frequency from any other OPP's frequency.
100  * @required_opps: List of OPPs that are required by this OPP.
101  * @opp_table:	points back to the opp_table struct this opp belongs to
102  * @np:		OPP's device node.
103  * @dentry:	debugfs dentry pointer (per opp)
104  *
105  * This structure stores the OPP information for a given device.
106  */
107 struct dev_pm_opp {
108 	struct list_head node;
109 	struct kref kref;
110 
111 	bool available;
112 	bool dynamic;
113 	bool turbo;
114 	bool suspend;
115 	bool removed;
116 	unsigned long *rates;
117 	unsigned int level;
118 
119 	struct dev_pm_opp_supply *supplies;
120 	struct dev_pm_opp_icc_bw *bandwidth;
121 
122 	unsigned long clock_latency_ns;
123 
124 	struct dev_pm_opp **required_opps;
125 	struct opp_table *opp_table;
126 
127 	struct device_node *np;
128 
129 #ifdef CONFIG_DEBUG_FS
130 	struct dentry *dentry;
131 	const char *of_name;
132 #endif
133 };
134 
135 /**
136  * struct opp_device - devices managed by 'struct opp_table'
137  * @node:	list node
138  * @dev:	device to which the struct object belongs
139  * @dentry:	debugfs dentry pointer (per device)
140  *
141  * This is an internal data structure maintaining the devices that are managed
142  * by 'struct opp_table'.
143  */
144 struct opp_device {
145 	struct list_head node;
146 	const struct device *dev;
147 
148 #ifdef CONFIG_DEBUG_FS
149 	struct dentry *dentry;
150 #endif
151 };
152 
153 enum opp_table_access {
154 	OPP_TABLE_ACCESS_UNKNOWN = 0,
155 	OPP_TABLE_ACCESS_EXCLUSIVE = 1,
156 	OPP_TABLE_ACCESS_SHARED = 2,
157 };
158 
159 /**
160  * struct opp_table - Device opp structure
161  * @node:	table node - contains the devices with OPPs that
162  *		have been registered. Nodes once added are not modified in this
163  *		table.
164  * @head:	notifier head to notify the OPP availability changes.
165  * @dev_list:	list of devices that share these OPPs
166  * @opp_list:	table of opps
167  * @kref:	for reference count of the table.
168  * @lock:	mutex protecting the opp_list and dev_list.
169  * @np:		struct device_node pointer for opp's DT node.
170  * @clock_latency_ns_max: Max clock latency in nanoseconds.
171  * @parsed_static_opps: Count of devices for which OPPs are initialized from DT.
172  * @shared_opp: OPP is shared between multiple devices.
173  * @current_rate_single_clk: Currently configured frequency for single clk.
174  * @current_opp: Currently configured OPP for the table.
175  * @suspend_opp: Pointer to OPP to be used during device suspend.
176  * @required_opp_tables: List of device OPP tables that are required by OPPs in
177  *		this table.
178  * @required_devs: List of devices for required OPP tables.
179  * @required_opp_count: Number of required devices.
180  * @supported_hw: Array of version number to support.
181  * @supported_hw_count: Number of elements in supported_hw array.
182  * @prop_name: A name to postfix to many DT properties, while parsing them.
183  * @config_clks: Platform specific config_clks() callback.
184  * @clks: Device's clock handles, for multiple clocks.
185  * @clk: Device's clock handle, for single clock.
186  * @clk_count: Number of clocks.
187  * @config_regulators: Platform specific config_regulators() callback.
188  * @regulators: Supply regulators
189  * @regulator_count: Number of power supply regulators. Its value can be -1
190  * (uninitialized), 0 (no opp-microvolt property) or > 0 (has opp-microvolt
191  * property).
192  * @paths: Interconnect path handles
193  * @path_count: Number of interconnect paths
194  * @enabled: Set to true if the device's resources are enabled/configured.
195  * @is_genpd: Marks if the OPP table belongs to a genpd.
196  * @dentry:	debugfs dentry pointer of the real device directory (not links).
197  * @dentry_name: Name of the real dentry.
198  *
199  * @voltage_tolerance_v1: In percentage, for v1 bindings only.
200  *
201  * This is an internal data structure maintaining the link to opps attached to
202  * a device. This structure is not meant to be shared to users as it is
203  * meant for book keeping and private to OPP library.
204  */
205 struct opp_table {
206 	struct list_head node, lazy;
207 
208 	struct blocking_notifier_head head;
209 	struct list_head dev_list;
210 	struct list_head opp_list;
211 	struct kref kref;
212 	struct mutex lock;
213 
214 	struct device_node *np;
215 	unsigned long clock_latency_ns_max;
216 
217 	/* For backward compatibility with v1 bindings */
218 	unsigned int voltage_tolerance_v1;
219 
220 	unsigned int parsed_static_opps;
221 	enum opp_table_access shared_opp;
222 	unsigned long current_rate_single_clk;
223 	struct dev_pm_opp *current_opp;
224 	struct dev_pm_opp *suspend_opp;
225 
226 	struct opp_table **required_opp_tables;
227 	struct device **required_devs;
228 	unsigned int required_opp_count;
229 
230 	unsigned int *supported_hw;
231 	unsigned int supported_hw_count;
232 	const char *prop_name;
233 	config_clks_t config_clks;
234 	struct clk **clks;
235 	struct clk *clk;
236 	int clk_count;
237 	config_regulators_t config_regulators;
238 	struct regulator **regulators;
239 	int regulator_count;
240 	struct icc_path **paths;
241 	unsigned int path_count;
242 	bool enabled;
243 	bool is_genpd;
244 
245 #ifdef CONFIG_DEBUG_FS
246 	struct dentry *dentry;
247 	char dentry_name[NAME_MAX];
248 #endif
249 };
250 
251 /* Routines internal to opp core */
252 void dev_pm_opp_get(struct dev_pm_opp *opp);
253 bool _opp_remove_all_static(struct opp_table *opp_table);
254 void _get_opp_table_kref(struct opp_table *opp_table);
255 int _get_opp_count(struct opp_table *opp_table);
256 struct opp_table *_find_opp_table(struct device *dev);
257 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
258 struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
259 void _opp_free(struct dev_pm_opp *opp);
260 int _opp_compare_key(struct opp_table *opp_table, struct dev_pm_opp *opp1, struct dev_pm_opp *opp2);
261 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
262 int _opp_add_v1(struct opp_table *opp_table, struct device *dev, struct dev_pm_opp_data *data, bool dynamic);
263 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu);
264 struct opp_table *_add_opp_table_indexed(struct device *dev, int index, bool getclk);
265 void _put_opp_list_kref(struct opp_table *opp_table);
266 void _required_opps_available(struct dev_pm_opp *opp, int count);
267 void _update_set_required_opps(struct opp_table *opp_table);
268 
269 static inline bool lazy_linking_pending(struct opp_table *opp_table)
270 {
271 	return unlikely(!list_empty(&opp_table->lazy));
272 }
273 
274 #ifdef CONFIG_OF
275 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index);
276 void _of_clear_opp_table(struct opp_table *opp_table);
277 struct opp_table *_managed_opp(struct device *dev, int index);
278 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp);
279 #else
280 static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index) {}
281 static inline void _of_clear_opp_table(struct opp_table *opp_table) {}
282 static inline struct opp_table *_managed_opp(struct device *dev, int index) { return NULL; }
283 static inline void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp) {}
284 #endif
285 
286 #ifdef CONFIG_DEBUG_FS
287 void opp_debug_remove_one(struct dev_pm_opp *opp);
288 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
289 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
290 void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
291 #else
292 static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}
293 
294 static inline void opp_debug_create_one(struct dev_pm_opp *opp,
295 					struct opp_table *opp_table) { }
296 
297 static inline void opp_debug_register(struct opp_device *opp_dev,
298 				      struct opp_table *opp_table) { }
299 
300 static inline void opp_debug_unregister(struct opp_device *opp_dev,
301 					struct opp_table *opp_table)
302 { }
303 #endif		/* DEBUG_FS */
304 
305 #endif		/* __DRIVER_OPP_H__ */
306