xref: /openbmc/linux/include/linux/scmi_protocol.h (revision 11a163f2)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * SCMI Message Protocol driver header
4  *
5  * Copyright (C) 2018 ARM Ltd.
6  */
7 
8 #ifndef _LINUX_SCMI_PROTOCOL_H
9 #define _LINUX_SCMI_PROTOCOL_H
10 
11 #include <linux/device.h>
12 #include <linux/notifier.h>
13 #include <linux/types.h>
14 
15 #define SCMI_MAX_STR_SIZE	16
16 #define SCMI_MAX_NUM_RATES	16
17 
18 /**
19  * struct scmi_revision_info - version information structure
20  *
21  * @major_ver: Major ABI version. Change here implies risk of backward
22  *	compatibility break.
23  * @minor_ver: Minor ABI version. Change here implies new feature addition,
24  *	or compatible change in ABI.
25  * @num_protocols: Number of protocols that are implemented, excluding the
26  *	base protocol.
27  * @num_agents: Number of agents in the system.
28  * @impl_ver: A vendor-specific implementation version.
29  * @vendor_id: A vendor identifier(Null terminated ASCII string)
30  * @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
31  */
32 struct scmi_revision_info {
33 	u16 major_ver;
34 	u16 minor_ver;
35 	u8 num_protocols;
36 	u8 num_agents;
37 	u32 impl_ver;
38 	char vendor_id[SCMI_MAX_STR_SIZE];
39 	char sub_vendor_id[SCMI_MAX_STR_SIZE];
40 };
41 
42 struct scmi_clock_info {
43 	char name[SCMI_MAX_STR_SIZE];
44 	bool rate_discrete;
45 	union {
46 		struct {
47 			int num_rates;
48 			u64 rates[SCMI_MAX_NUM_RATES];
49 		} list;
50 		struct {
51 			u64 min_rate;
52 			u64 max_rate;
53 			u64 step_size;
54 		} range;
55 	};
56 };
57 
58 struct scmi_handle;
59 
60 /**
61  * struct scmi_clk_ops - represents the various operations provided
62  *	by SCMI Clock Protocol
63  *
64  * @count_get: get the count of clocks provided by SCMI
65  * @info_get: get the information of the specified clock
66  * @rate_get: request the current clock rate of a clock
67  * @rate_set: set the clock rate of a clock
68  * @enable: enables the specified clock
69  * @disable: disables the specified clock
70  */
71 struct scmi_clk_ops {
72 	int (*count_get)(const struct scmi_handle *handle);
73 
74 	const struct scmi_clock_info *(*info_get)
75 		(const struct scmi_handle *handle, u32 clk_id);
76 	int (*rate_get)(const struct scmi_handle *handle, u32 clk_id,
77 			u64 *rate);
78 	int (*rate_set)(const struct scmi_handle *handle, u32 clk_id,
79 			u64 rate);
80 	int (*enable)(const struct scmi_handle *handle, u32 clk_id);
81 	int (*disable)(const struct scmi_handle *handle, u32 clk_id);
82 };
83 
84 /**
85  * struct scmi_perf_ops - represents the various operations provided
86  *	by SCMI Performance Protocol
87  *
88  * @limits_set: sets limits on the performance level of a domain
89  * @limits_get: gets limits on the performance level of a domain
90  * @level_set: sets the performance level of a domain
91  * @level_get: gets the performance level of a domain
92  * @device_domain_id: gets the scmi domain id for a given device
93  * @transition_latency_get: gets the DVFS transition latency for a given device
94  * @device_opps_add: adds all the OPPs for a given device
95  * @freq_set: sets the frequency for a given device using sustained frequency
96  *	to sustained performance level mapping
97  * @freq_get: gets the frequency for a given device using sustained frequency
98  *	to sustained performance level mapping
99  * @est_power_get: gets the estimated power cost for a given performance domain
100  *	at a given frequency
101  */
102 struct scmi_perf_ops {
103 	int (*limits_set)(const struct scmi_handle *handle, u32 domain,
104 			  u32 max_perf, u32 min_perf);
105 	int (*limits_get)(const struct scmi_handle *handle, u32 domain,
106 			  u32 *max_perf, u32 *min_perf);
107 	int (*level_set)(const struct scmi_handle *handle, u32 domain,
108 			 u32 level, bool poll);
109 	int (*level_get)(const struct scmi_handle *handle, u32 domain,
110 			 u32 *level, bool poll);
111 	int (*device_domain_id)(struct device *dev);
112 	int (*transition_latency_get)(const struct scmi_handle *handle,
113 				      struct device *dev);
114 	int (*device_opps_add)(const struct scmi_handle *handle,
115 			       struct device *dev);
116 	int (*freq_set)(const struct scmi_handle *handle, u32 domain,
117 			unsigned long rate, bool poll);
118 	int (*freq_get)(const struct scmi_handle *handle, u32 domain,
119 			unsigned long *rate, bool poll);
120 	int (*est_power_get)(const struct scmi_handle *handle, u32 domain,
121 			     unsigned long *rate, unsigned long *power);
122 	bool (*fast_switch_possible)(const struct scmi_handle *handle,
123 				     struct device *dev);
124 };
125 
126 /**
127  * struct scmi_power_ops - represents the various operations provided
128  *	by SCMI Power Protocol
129  *
130  * @num_domains_get: get the count of power domains provided by SCMI
131  * @name_get: gets the name of a power domain
132  * @state_set: sets the power state of a power domain
133  * @state_get: gets the power state of a power domain
134  */
135 struct scmi_power_ops {
136 	int (*num_domains_get)(const struct scmi_handle *handle);
137 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
138 #define SCMI_POWER_STATE_TYPE_SHIFT	30
139 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
140 #define SCMI_POWER_STATE_PARAM(type, id) \
141 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
142 		((id) & SCMI_POWER_STATE_ID_MASK))
143 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
144 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
145 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
146 			 u32 state);
147 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
148 			 u32 *state);
149 };
150 
151 struct scmi_sensor_info {
152 	u32 id;
153 	u8 type;
154 	s8 scale;
155 	u8 num_trip_points;
156 	bool async;
157 	char name[SCMI_MAX_STR_SIZE];
158 };
159 
160 /*
161  * Partial list from Distributed Management Task Force (DMTF) specification:
162  * DSP0249 (Platform Level Data Model specification)
163  */
164 enum scmi_sensor_class {
165 	NONE = 0x0,
166 	TEMPERATURE_C = 0x2,
167 	VOLTAGE = 0x5,
168 	CURRENT = 0x6,
169 	POWER = 0x7,
170 	ENERGY = 0x8,
171 };
172 
173 /**
174  * struct scmi_sensor_ops - represents the various operations provided
175  *	by SCMI Sensor Protocol
176  *
177  * @count_get: get the count of sensors provided by SCMI
178  * @info_get: get the information of the specified sensor
179  * @trip_point_config: selects and configures a trip-point of interest
180  * @reading_get: gets the current value of the sensor
181  */
182 struct scmi_sensor_ops {
183 	int (*count_get)(const struct scmi_handle *handle);
184 	const struct scmi_sensor_info *(*info_get)
185 		(const struct scmi_handle *handle, u32 sensor_id);
186 	int (*trip_point_config)(const struct scmi_handle *handle,
187 				 u32 sensor_id, u8 trip_id, u64 trip_value);
188 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
189 			   u64 *value);
190 };
191 
192 /**
193  * struct scmi_reset_ops - represents the various operations provided
194  *	by SCMI Reset Protocol
195  *
196  * @num_domains_get: get the count of reset domains provided by SCMI
197  * @name_get: gets the name of a reset domain
198  * @latency_get: gets the reset latency for the specified reset domain
199  * @reset: resets the specified reset domain
200  * @assert: explicitly assert reset signal of the specified reset domain
201  * @deassert: explicitly deassert reset signal of the specified reset domain
202  */
203 struct scmi_reset_ops {
204 	int (*num_domains_get)(const struct scmi_handle *handle);
205 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
206 	int (*latency_get)(const struct scmi_handle *handle, u32 domain);
207 	int (*reset)(const struct scmi_handle *handle, u32 domain);
208 	int (*assert)(const struct scmi_handle *handle, u32 domain);
209 	int (*deassert)(const struct scmi_handle *handle, u32 domain);
210 };
211 
212 /**
213  * struct scmi_notify_ops  - represents notifications' operations provided by
214  * SCMI core
215  * @register_event_notifier: Register a notifier_block for the requested event
216  * @unregister_event_notifier: Unregister a notifier_block for the requested
217  *			       event
218  *
219  * A user can register/unregister its own notifier_block against the wanted
220  * platform instance regarding the desired event identified by the
221  * tuple: (proto_id, evt_id, src_id) using the provided register/unregister
222  * interface where:
223  *
224  * @handle: The handle identifying the platform instance to use
225  * @proto_id: The protocol ID as in SCMI Specification
226  * @evt_id: The message ID of the desired event as in SCMI Specification
227  * @src_id: A pointer to the desired source ID if different sources are
228  *	    possible for the protocol (like domain_id, sensor_id...etc)
229  *
230  * @src_id can be provided as NULL if it simply does NOT make sense for
231  * the protocol at hand, OR if the user is explicitly interested in
232  * receiving notifications from ANY existent source associated to the
233  * specified proto_id / evt_id.
234  *
235  * Received notifications are finally delivered to the registered users,
236  * invoking the callback provided with the notifier_block *nb as follows:
237  *
238  *	int user_cb(nb, evt_id, report)
239  *
240  * with:
241  *
242  * @nb: The notifier block provided by the user
243  * @evt_id: The message ID of the delivered event
244  * @report: A custom struct describing the specific event delivered
245  */
246 struct scmi_notify_ops {
247 	int (*register_event_notifier)(const struct scmi_handle *handle,
248 				       u8 proto_id, u8 evt_id, u32 *src_id,
249 				       struct notifier_block *nb);
250 	int (*unregister_event_notifier)(const struct scmi_handle *handle,
251 					 u8 proto_id, u8 evt_id, u32 *src_id,
252 					 struct notifier_block *nb);
253 };
254 
255 /**
256  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
257  *
258  * @dev: pointer to the SCMI device
259  * @version: pointer to the structure containing SCMI version information
260  * @power_ops: pointer to set of power protocol operations
261  * @perf_ops: pointer to set of performance protocol operations
262  * @clk_ops: pointer to set of clock protocol operations
263  * @sensor_ops: pointer to set of sensor protocol operations
264  * @reset_ops: pointer to set of reset protocol operations
265  * @notify_ops: pointer to set of notifications related operations
266  * @perf_priv: pointer to private data structure specific to performance
267  *	protocol(for internal use only)
268  * @clk_priv: pointer to private data structure specific to clock
269  *	protocol(for internal use only)
270  * @power_priv: pointer to private data structure specific to power
271  *	protocol(for internal use only)
272  * @sensor_priv: pointer to private data structure specific to sensors
273  *	protocol(for internal use only)
274  * @reset_priv: pointer to private data structure specific to reset
275  *	protocol(for internal use only)
276  * @notify_priv: pointer to private data structure specific to notifications
277  *	(for internal use only)
278  */
279 struct scmi_handle {
280 	struct device *dev;
281 	struct scmi_revision_info *version;
282 	const struct scmi_perf_ops *perf_ops;
283 	const struct scmi_clk_ops *clk_ops;
284 	const struct scmi_power_ops *power_ops;
285 	const struct scmi_sensor_ops *sensor_ops;
286 	const struct scmi_reset_ops *reset_ops;
287 	const struct scmi_notify_ops *notify_ops;
288 	/* for protocol internal use */
289 	void *perf_priv;
290 	void *clk_priv;
291 	void *power_priv;
292 	void *sensor_priv;
293 	void *reset_priv;
294 	void *notify_priv;
295 	void *system_priv;
296 };
297 
298 enum scmi_std_protocol {
299 	SCMI_PROTOCOL_BASE = 0x10,
300 	SCMI_PROTOCOL_POWER = 0x11,
301 	SCMI_PROTOCOL_SYSTEM = 0x12,
302 	SCMI_PROTOCOL_PERF = 0x13,
303 	SCMI_PROTOCOL_CLOCK = 0x14,
304 	SCMI_PROTOCOL_SENSOR = 0x15,
305 	SCMI_PROTOCOL_RESET = 0x16,
306 };
307 
308 enum scmi_system_events {
309 	SCMI_SYSTEM_SHUTDOWN,
310 	SCMI_SYSTEM_COLDRESET,
311 	SCMI_SYSTEM_WARMRESET,
312 	SCMI_SYSTEM_POWERUP,
313 	SCMI_SYSTEM_SUSPEND,
314 	SCMI_SYSTEM_MAX
315 };
316 
317 struct scmi_device {
318 	u32 id;
319 	u8 protocol_id;
320 	const char *name;
321 	struct device dev;
322 	struct scmi_handle *handle;
323 };
324 
325 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
326 
327 struct scmi_device *
328 scmi_device_create(struct device_node *np, struct device *parent, int protocol,
329 		   const char *name);
330 void scmi_device_destroy(struct scmi_device *scmi_dev);
331 
332 struct scmi_device_id {
333 	u8 protocol_id;
334 	const char *name;
335 };
336 
337 struct scmi_driver {
338 	const char *name;
339 	int (*probe)(struct scmi_device *sdev);
340 	void (*remove)(struct scmi_device *sdev);
341 	const struct scmi_device_id *id_table;
342 
343 	struct device_driver driver;
344 };
345 
346 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
347 
348 #if IS_REACHABLE(CONFIG_ARM_SCMI_PROTOCOL)
349 int scmi_driver_register(struct scmi_driver *driver,
350 			 struct module *owner, const char *mod_name);
351 void scmi_driver_unregister(struct scmi_driver *driver);
352 #else
353 static inline int
354 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
355 		     const char *mod_name)
356 {
357 	return -EINVAL;
358 }
359 
360 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
361 #endif /* CONFIG_ARM_SCMI_PROTOCOL */
362 
363 #define scmi_register(driver) \
364 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
365 #define scmi_unregister(driver) \
366 	scmi_driver_unregister(driver)
367 
368 /**
369  * module_scmi_driver() - Helper macro for registering a scmi driver
370  * @__scmi_driver: scmi_driver structure
371  *
372  * Helper macro for scmi drivers to set up proper module init / exit
373  * functions.  Replaces module_init() and module_exit() and keeps people from
374  * printing pointless things to the kernel log when their driver is loaded.
375  */
376 #define module_scmi_driver(__scmi_driver)	\
377 	module_driver(__scmi_driver, scmi_register, scmi_unregister)
378 
379 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
380 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
381 void scmi_protocol_unregister(int protocol_id);
382 
383 /* SCMI Notification API - Custom Event Reports */
384 enum scmi_notification_events {
385 	SCMI_EVENT_POWER_STATE_CHANGED = 0x0,
386 	SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0,
387 	SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1,
388 	SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0,
389 	SCMI_EVENT_RESET_ISSUED = 0x0,
390 	SCMI_EVENT_BASE_ERROR_EVENT = 0x0,
391 	SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER = 0x0,
392 };
393 
394 struct scmi_power_state_changed_report {
395 	ktime_t		timestamp;
396 	unsigned int	agent_id;
397 	unsigned int	domain_id;
398 	unsigned int	power_state;
399 };
400 
401 struct scmi_system_power_state_notifier_report {
402 	ktime_t		timestamp;
403 	unsigned int	agent_id;
404 	unsigned int	flags;
405 	unsigned int	system_state;
406 };
407 
408 struct scmi_perf_limits_report {
409 	ktime_t		timestamp;
410 	unsigned int	agent_id;
411 	unsigned int	domain_id;
412 	unsigned int	range_max;
413 	unsigned int	range_min;
414 };
415 
416 struct scmi_perf_level_report {
417 	ktime_t		timestamp;
418 	unsigned int	agent_id;
419 	unsigned int	domain_id;
420 	unsigned int	performance_level;
421 };
422 
423 struct scmi_sensor_trip_point_report {
424 	ktime_t		timestamp;
425 	unsigned int	agent_id;
426 	unsigned int	sensor_id;
427 	unsigned int	trip_point_desc;
428 };
429 
430 struct scmi_reset_issued_report {
431 	ktime_t		timestamp;
432 	unsigned int	agent_id;
433 	unsigned int	domain_id;
434 	unsigned int	reset_state;
435 };
436 
437 struct scmi_base_error_report {
438 	ktime_t			timestamp;
439 	unsigned int		agent_id;
440 	bool			fatal;
441 	unsigned int		cmd_count;
442 	unsigned long long	reports[];
443 };
444 
445 #endif /* _LINUX_SCMI_PROTOCOL_H */
446