xref: /openbmc/linux/drivers/opp/opp.h (revision f4356947)
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, lazy_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 
39 /**
40  * struct opp_config_data - data for set config operations
41  * @opp_table: OPP table
42  * @flags: OPP config flags
43  *
44  * This structure stores the OPP config information for each OPP table
45  * configuration by the callers.
46  */
47 struct opp_config_data {
48 	struct opp_table *opp_table;
49 	unsigned int flags;
50 };
51 
52 /*
53  * Internal data structure organization with the OPP layer library is as
54  * follows:
55  * opp_tables (root)
56  *	|- device 1 (represents voltage domain 1)
57  *	|	|- opp 1 (availability, freq, voltage)
58  *	|	|- opp 2 ..
59  *	...	...
60  *	|	`- opp n ..
61  *	|- device 2 (represents the next voltage domain)
62  *	...
63  *	`- device m (represents mth voltage domain)
64  * device 1, 2.. are represented by opp_table structure while each opp
65  * is represented by the opp structure.
66  */
67 
68 /**
69  * struct dev_pm_opp - Generic OPP description structure
70  * @node:	opp table node. The nodes are maintained throughout the lifetime
71  *		of boot. It is expected only an optimal set of OPPs are
72  *		added to the library by the SoC framework.
73  *		IMPORTANT: the opp nodes should be maintained in increasing
74  *		order.
75  * @kref:	for reference count of the OPP.
76  * @available:	true/false - marks if this OPP as available or not
77  * @dynamic:	not-created from static DT entries.
78  * @turbo:	true if turbo (boost) OPP
79  * @suspend:	true if suspend OPP
80  * @removed:	flag indicating that OPP's reference is dropped by OPP core.
81  * @pstate: Device's power domain's performance state.
82  * @rates:	Frequencies in hertz
83  * @level:	Performance level
84  * @supplies:	Power supplies voltage/current values
85  * @bandwidth:	Interconnect bandwidth values
86  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
87  *		frequency from any other OPP's frequency.
88  * @required_opps: List of OPPs that are required by this OPP.
89  * @opp_table:	points back to the opp_table struct this opp belongs to
90  * @np:		OPP's device node.
91  * @dentry:	debugfs dentry pointer (per opp)
92  *
93  * This structure stores the OPP information for a given device.
94  */
95 struct dev_pm_opp {
96 	struct list_head node;
97 	struct kref kref;
98 
99 	bool available;
100 	bool dynamic;
101 	bool turbo;
102 	bool suspend;
103 	bool removed;
104 	unsigned int pstate;
105 	unsigned long *rates;
106 	unsigned int level;
107 
108 	struct dev_pm_opp_supply *supplies;
109 	struct dev_pm_opp_icc_bw *bandwidth;
110 
111 	unsigned long clock_latency_ns;
112 
113 	struct dev_pm_opp **required_opps;
114 	struct opp_table *opp_table;
115 
116 	struct device_node *np;
117 
118 #ifdef CONFIG_DEBUG_FS
119 	struct dentry *dentry;
120 	const char *of_name;
121 #endif
122 };
123 
124 /**
125  * struct opp_device - devices managed by 'struct opp_table'
126  * @node:	list node
127  * @dev:	device to which the struct object belongs
128  * @dentry:	debugfs dentry pointer (per device)
129  *
130  * This is an internal data structure maintaining the devices that are managed
131  * by 'struct opp_table'.
132  */
133 struct opp_device {
134 	struct list_head node;
135 	const struct device *dev;
136 
137 #ifdef CONFIG_DEBUG_FS
138 	struct dentry *dentry;
139 #endif
140 };
141 
142 enum opp_table_access {
143 	OPP_TABLE_ACCESS_UNKNOWN = 0,
144 	OPP_TABLE_ACCESS_EXCLUSIVE = 1,
145 	OPP_TABLE_ACCESS_SHARED = 2,
146 };
147 
148 /**
149  * struct opp_table - Device opp structure
150  * @node:	table node - contains the devices with OPPs that
151  *		have been registered. Nodes once added are not modified in this
152  *		table.
153  * @head:	notifier head to notify the OPP availability changes.
154  * @dev_list:	list of devices that share these OPPs
155  * @opp_list:	table of opps
156  * @kref:	for reference count of the table.
157  * @lock:	mutex protecting the opp_list and dev_list.
158  * @np:		struct device_node pointer for opp's DT node.
159  * @clock_latency_ns_max: Max clock latency in nanoseconds.
160  * @parsed_static_opps: Count of devices for which OPPs are initialized from DT.
161  * @shared_opp: OPP is shared between multiple devices.
162  * @rate_clk_single: Currently configured frequency for single clk.
163  * @current_opp: Currently configured OPP for the table.
164  * @suspend_opp: Pointer to OPP to be used during device suspend.
165  * @genpd_virt_dev_lock: Mutex protecting the genpd virtual device pointers.
166  * @genpd_virt_devs: List of virtual devices for multiple genpd support.
167  * @required_opp_tables: List of device OPP tables that are required by OPPs in
168  *		this table.
169  * @required_opp_count: Number of required devices.
170  * @supported_hw: Array of version number to support.
171  * @supported_hw_count: Number of elements in supported_hw array.
172  * @prop_name: A name to postfix to many DT properties, while parsing them.
173  * @config_clks: Platform specific config_clks() callback.
174  * @clks: Device's clock handles, for multiple clocks.
175  * @clk: Device's clock handle, for single clock.
176  * @clk_count: Number of clocks.
177  * @config_regulators: Platform specific config_regulators() callback.
178  * @regulators: Supply regulators
179  * @regulator_count: Number of power supply regulators. Its value can be -1
180  * (uninitialized), 0 (no opp-microvolt property) or > 0 (has opp-microvolt
181  * property).
182  * @paths: Interconnect path handles
183  * @path_count: Number of interconnect paths
184  * @enabled: Set to true if the device's resources are enabled/configured.
185  * @genpd_performance_state: Device's power domain support performance state.
186  * @is_genpd: Marks if the OPP table belongs to a genpd.
187  * @set_required_opps: Helper responsible to set required OPPs.
188  * @dentry:	debugfs dentry pointer of the real device directory (not links).
189  * @dentry_name: Name of the real dentry.
190  *
191  * @voltage_tolerance_v1: In percentage, for v1 bindings only.
192  *
193  * This is an internal data structure maintaining the link to opps attached to
194  * a device. This structure is not meant to be shared to users as it is
195  * meant for book keeping and private to OPP library.
196  */
197 struct opp_table {
198 	struct list_head node, lazy;
199 
200 	struct blocking_notifier_head head;
201 	struct list_head dev_list;
202 	struct list_head opp_list;
203 	struct kref kref;
204 	struct mutex lock;
205 
206 	struct device_node *np;
207 	unsigned long clock_latency_ns_max;
208 
209 	/* For backward compatibility with v1 bindings */
210 	unsigned int voltage_tolerance_v1;
211 
212 	unsigned int parsed_static_opps;
213 	enum opp_table_access shared_opp;
214 	unsigned long rate_clk_single;
215 	struct dev_pm_opp *current_opp;
216 	struct dev_pm_opp *suspend_opp;
217 
218 	struct mutex genpd_virt_dev_lock;
219 	struct device **genpd_virt_devs;
220 	struct opp_table **required_opp_tables;
221 	unsigned int required_opp_count;
222 
223 	unsigned int *supported_hw;
224 	unsigned int supported_hw_count;
225 	const char *prop_name;
226 	config_clks_t config_clks;
227 	struct clk **clks;
228 	struct clk *clk;
229 	int clk_count;
230 	config_regulators_t config_regulators;
231 	struct regulator **regulators;
232 	int regulator_count;
233 	struct icc_path **paths;
234 	unsigned int path_count;
235 	bool enabled;
236 	bool genpd_performance_state;
237 	bool is_genpd;
238 	int (*set_required_opps)(struct device *dev,
239 		struct opp_table *opp_table, struct dev_pm_opp *opp, bool scaling_down);
240 
241 #ifdef CONFIG_DEBUG_FS
242 	struct dentry *dentry;
243 	char dentry_name[NAME_MAX];
244 #endif
245 };
246 
247 /* Routines internal to opp core */
248 void dev_pm_opp_get(struct dev_pm_opp *opp);
249 bool _opp_remove_all_static(struct opp_table *opp_table);
250 void _get_opp_table_kref(struct opp_table *opp_table);
251 int _get_opp_count(struct opp_table *opp_table);
252 struct opp_table *_find_opp_table(struct device *dev);
253 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
254 struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
255 void _opp_free(struct dev_pm_opp *opp);
256 int _opp_compare_key(struct opp_table *opp_table, struct dev_pm_opp *opp1, struct dev_pm_opp *opp2);
257 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
258 int _opp_add_v1(struct opp_table *opp_table, struct device *dev, unsigned long freq, long u_volt, bool dynamic);
259 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu);
260 struct opp_table *_add_opp_table_indexed(struct device *dev, int index, bool getclk);
261 void _put_opp_list_kref(struct opp_table *opp_table);
262 void _required_opps_available(struct dev_pm_opp *opp, int count);
263 void _update_set_required_opps(struct opp_table *opp_table);
264 
265 static inline bool lazy_linking_pending(struct opp_table *opp_table)
266 {
267 	return unlikely(!list_empty(&opp_table->lazy));
268 }
269 
270 #ifdef CONFIG_OF
271 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index);
272 void _of_clear_opp_table(struct opp_table *opp_table);
273 struct opp_table *_managed_opp(struct device *dev, int index);
274 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp);
275 #else
276 static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev, int index) {}
277 static inline void _of_clear_opp_table(struct opp_table *opp_table) {}
278 static inline struct opp_table *_managed_opp(struct device *dev, int index) { return NULL; }
279 static inline void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp) {}
280 #endif
281 
282 #ifdef CONFIG_DEBUG_FS
283 void opp_debug_remove_one(struct dev_pm_opp *opp);
284 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
285 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
286 void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
287 #else
288 static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}
289 
290 static inline void opp_debug_create_one(struct dev_pm_opp *opp,
291 					struct opp_table *opp_table) { }
292 
293 static inline void opp_debug_register(struct opp_device *opp_dev,
294 				      struct opp_table *opp_table) { }
295 
296 static inline void opp_debug_unregister(struct opp_device *opp_dev,
297 					struct opp_table *opp_table)
298 { }
299 #endif		/* DEBUG_FS */
300 
301 #endif		/* __DRIVER_OPP_H__ */
302