xref: /openbmc/linux/include/linux/scmi_protocol.h (revision f5ad1c74)
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 	bool (*power_scale_mw_get)(const struct scmi_handle *handle);
125 };
126 
127 /**
128  * struct scmi_power_ops - represents the various operations provided
129  *	by SCMI Power Protocol
130  *
131  * @num_domains_get: get the count of power domains provided by SCMI
132  * @name_get: gets the name of a power domain
133  * @state_set: sets the power state of a power domain
134  * @state_get: gets the power state of a power domain
135  */
136 struct scmi_power_ops {
137 	int (*num_domains_get)(const struct scmi_handle *handle);
138 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
139 #define SCMI_POWER_STATE_TYPE_SHIFT	30
140 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
141 #define SCMI_POWER_STATE_PARAM(type, id) \
142 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
143 		((id) & SCMI_POWER_STATE_ID_MASK))
144 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
145 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
146 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
147 			 u32 state);
148 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
149 			 u32 *state);
150 };
151 
152 struct scmi_sensor_info {
153 	u32 id;
154 	u8 type;
155 	s8 scale;
156 	u8 num_trip_points;
157 	bool async;
158 	char name[SCMI_MAX_STR_SIZE];
159 };
160 
161 /*
162  * Partial list from Distributed Management Task Force (DMTF) specification:
163  * DSP0249 (Platform Level Data Model specification)
164  */
165 enum scmi_sensor_class {
166 	NONE = 0x0,
167 	TEMPERATURE_C = 0x2,
168 	VOLTAGE = 0x5,
169 	CURRENT = 0x6,
170 	POWER = 0x7,
171 	ENERGY = 0x8,
172 };
173 
174 /**
175  * struct scmi_sensor_ops - represents the various operations provided
176  *	by SCMI Sensor Protocol
177  *
178  * @count_get: get the count of sensors provided by SCMI
179  * @info_get: get the information of the specified sensor
180  * @trip_point_config: selects and configures a trip-point of interest
181  * @reading_get: gets the current value of the sensor
182  */
183 struct scmi_sensor_ops {
184 	int (*count_get)(const struct scmi_handle *handle);
185 	const struct scmi_sensor_info *(*info_get)
186 		(const struct scmi_handle *handle, u32 sensor_id);
187 	int (*trip_point_config)(const struct scmi_handle *handle,
188 				 u32 sensor_id, u8 trip_id, u64 trip_value);
189 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
190 			   u64 *value);
191 };
192 
193 /**
194  * struct scmi_reset_ops - represents the various operations provided
195  *	by SCMI Reset Protocol
196  *
197  * @num_domains_get: get the count of reset domains provided by SCMI
198  * @name_get: gets the name of a reset domain
199  * @latency_get: gets the reset latency for the specified reset domain
200  * @reset: resets the specified reset domain
201  * @assert: explicitly assert reset signal of the specified reset domain
202  * @deassert: explicitly deassert reset signal of the specified reset domain
203  */
204 struct scmi_reset_ops {
205 	int (*num_domains_get)(const struct scmi_handle *handle);
206 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
207 	int (*latency_get)(const struct scmi_handle *handle, u32 domain);
208 	int (*reset)(const struct scmi_handle *handle, u32 domain);
209 	int (*assert)(const struct scmi_handle *handle, u32 domain);
210 	int (*deassert)(const struct scmi_handle *handle, u32 domain);
211 };
212 
213 /**
214  * struct scmi_voltage_info - describe one available SCMI Voltage Domain
215  *
216  * @id: the domain ID as advertised by the platform
217  * @segmented: defines the layout of the entries of array @levels_uv.
218  *	       - when True the entries are to be interpreted as triplets,
219  *	         each defining a segment representing a range of equally
220  *	         space voltages: <lowest_volts>, <highest_volt>, <step_uV>
221  *	       - when False the entries simply represent a single discrete
222  *	         supported voltage level
223  * @negative_volts_allowed: True if any of the entries of @levels_uv represent
224  *			    a negative voltage.
225  * @attributes: represents Voltage Domain advertised attributes
226  * @name: name assigned to the Voltage Domain by platform
227  * @num_levels: number of total entries in @levels_uv.
228  * @levels_uv: array of entries describing the available voltage levels for
229  *	       this domain.
230  */
231 struct scmi_voltage_info {
232 	unsigned int id;
233 	bool segmented;
234 	bool negative_volts_allowed;
235 	unsigned int attributes;
236 	char name[SCMI_MAX_STR_SIZE];
237 	unsigned int num_levels;
238 #define SCMI_VOLTAGE_SEGMENT_LOW	0
239 #define SCMI_VOLTAGE_SEGMENT_HIGH	1
240 #define SCMI_VOLTAGE_SEGMENT_STEP	2
241 	int *levels_uv;
242 };
243 
244 /**
245  * struct scmi_voltage_ops - represents the various operations provided
246  * by SCMI Voltage Protocol
247  *
248  * @num_domains_get: get the count of voltage domains provided by SCMI
249  * @info_get: get the information of the specified domain
250  * @config_set: set the config for the specified domain
251  * @config_get: get the config of the specified domain
252  * @level_set: set the voltage level for the specified domain
253  * @level_get: get the voltage level of the specified domain
254  */
255 struct scmi_voltage_ops {
256 	int (*num_domains_get)(const struct scmi_handle *handle);
257 	const struct scmi_voltage_info __must_check *(*info_get)
258 		(const struct scmi_handle *handle, u32 domain_id);
259 	int (*config_set)(const struct scmi_handle *handle, u32 domain_id,
260 			  u32 config);
261 #define	SCMI_VOLTAGE_ARCH_STATE_OFF		0x0
262 #define	SCMI_VOLTAGE_ARCH_STATE_ON		0x7
263 	int (*config_get)(const struct scmi_handle *handle, u32 domain_id,
264 			  u32 *config);
265 	int (*level_set)(const struct scmi_handle *handle, u32 domain_id,
266 			 u32 flags, s32 volt_uV);
267 	int (*level_get)(const struct scmi_handle *handle, u32 domain_id,
268 			 s32 *volt_uV);
269 };
270 
271 /**
272  * struct scmi_notify_ops  - represents notifications' operations provided by
273  * SCMI core
274  * @register_event_notifier: Register a notifier_block for the requested event
275  * @unregister_event_notifier: Unregister a notifier_block for the requested
276  *			       event
277  *
278  * A user can register/unregister its own notifier_block against the wanted
279  * platform instance regarding the desired event identified by the
280  * tuple: (proto_id, evt_id, src_id) using the provided register/unregister
281  * interface where:
282  *
283  * @handle: The handle identifying the platform instance to use
284  * @proto_id: The protocol ID as in SCMI Specification
285  * @evt_id: The message ID of the desired event as in SCMI Specification
286  * @src_id: A pointer to the desired source ID if different sources are
287  *	    possible for the protocol (like domain_id, sensor_id...etc)
288  *
289  * @src_id can be provided as NULL if it simply does NOT make sense for
290  * the protocol at hand, OR if the user is explicitly interested in
291  * receiving notifications from ANY existent source associated to the
292  * specified proto_id / evt_id.
293  *
294  * Received notifications are finally delivered to the registered users,
295  * invoking the callback provided with the notifier_block *nb as follows:
296  *
297  *	int user_cb(nb, evt_id, report)
298  *
299  * with:
300  *
301  * @nb: The notifier block provided by the user
302  * @evt_id: The message ID of the delivered event
303  * @report: A custom struct describing the specific event delivered
304  */
305 struct scmi_notify_ops {
306 	int (*register_event_notifier)(const struct scmi_handle *handle,
307 				       u8 proto_id, u8 evt_id, u32 *src_id,
308 				       struct notifier_block *nb);
309 	int (*unregister_event_notifier)(const struct scmi_handle *handle,
310 					 u8 proto_id, u8 evt_id, u32 *src_id,
311 					 struct notifier_block *nb);
312 };
313 
314 /**
315  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
316  *
317  * @dev: pointer to the SCMI device
318  * @version: pointer to the structure containing SCMI version information
319  * @power_ops: pointer to set of power protocol operations
320  * @perf_ops: pointer to set of performance protocol operations
321  * @clk_ops: pointer to set of clock protocol operations
322  * @sensor_ops: pointer to set of sensor protocol operations
323  * @reset_ops: pointer to set of reset protocol operations
324  * @voltage_ops: pointer to set of voltage protocol operations
325  * @notify_ops: pointer to set of notifications related operations
326  * @perf_priv: pointer to private data structure specific to performance
327  *	protocol(for internal use only)
328  * @clk_priv: pointer to private data structure specific to clock
329  *	protocol(for internal use only)
330  * @power_priv: pointer to private data structure specific to power
331  *	protocol(for internal use only)
332  * @sensor_priv: pointer to private data structure specific to sensors
333  *	protocol(for internal use only)
334  * @reset_priv: pointer to private data structure specific to reset
335  *	protocol(for internal use only)
336  * @voltage_priv: pointer to private data structure specific to voltage
337  *	protocol(for internal use only)
338  * @notify_priv: pointer to private data structure specific to notifications
339  *	(for internal use only)
340  */
341 struct scmi_handle {
342 	struct device *dev;
343 	struct scmi_revision_info *version;
344 	const struct scmi_perf_ops *perf_ops;
345 	const struct scmi_clk_ops *clk_ops;
346 	const struct scmi_power_ops *power_ops;
347 	const struct scmi_sensor_ops *sensor_ops;
348 	const struct scmi_reset_ops *reset_ops;
349 	const struct scmi_voltage_ops *voltage_ops;
350 	const struct scmi_notify_ops *notify_ops;
351 	/* for protocol internal use */
352 	void *perf_priv;
353 	void *clk_priv;
354 	void *power_priv;
355 	void *sensor_priv;
356 	void *reset_priv;
357 	void *voltage_priv;
358 	void *notify_priv;
359 	void *system_priv;
360 };
361 
362 enum scmi_std_protocol {
363 	SCMI_PROTOCOL_BASE = 0x10,
364 	SCMI_PROTOCOL_POWER = 0x11,
365 	SCMI_PROTOCOL_SYSTEM = 0x12,
366 	SCMI_PROTOCOL_PERF = 0x13,
367 	SCMI_PROTOCOL_CLOCK = 0x14,
368 	SCMI_PROTOCOL_SENSOR = 0x15,
369 	SCMI_PROTOCOL_RESET = 0x16,
370 	SCMI_PROTOCOL_VOLTAGE = 0x17,
371 };
372 
373 enum scmi_system_events {
374 	SCMI_SYSTEM_SHUTDOWN,
375 	SCMI_SYSTEM_COLDRESET,
376 	SCMI_SYSTEM_WARMRESET,
377 	SCMI_SYSTEM_POWERUP,
378 	SCMI_SYSTEM_SUSPEND,
379 	SCMI_SYSTEM_MAX
380 };
381 
382 struct scmi_device {
383 	u32 id;
384 	u8 protocol_id;
385 	const char *name;
386 	struct device dev;
387 	struct scmi_handle *handle;
388 };
389 
390 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
391 
392 struct scmi_device *
393 scmi_device_create(struct device_node *np, struct device *parent, int protocol,
394 		   const char *name);
395 void scmi_device_destroy(struct scmi_device *scmi_dev);
396 
397 struct scmi_device_id {
398 	u8 protocol_id;
399 	const char *name;
400 };
401 
402 struct scmi_driver {
403 	const char *name;
404 	int (*probe)(struct scmi_device *sdev);
405 	void (*remove)(struct scmi_device *sdev);
406 	const struct scmi_device_id *id_table;
407 
408 	struct device_driver driver;
409 };
410 
411 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
412 
413 #if IS_REACHABLE(CONFIG_ARM_SCMI_PROTOCOL)
414 int scmi_driver_register(struct scmi_driver *driver,
415 			 struct module *owner, const char *mod_name);
416 void scmi_driver_unregister(struct scmi_driver *driver);
417 #else
418 static inline int
419 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
420 		     const char *mod_name)
421 {
422 	return -EINVAL;
423 }
424 
425 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
426 #endif /* CONFIG_ARM_SCMI_PROTOCOL */
427 
428 #define scmi_register(driver) \
429 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
430 #define scmi_unregister(driver) \
431 	scmi_driver_unregister(driver)
432 
433 /**
434  * module_scmi_driver() - Helper macro for registering a scmi driver
435  * @__scmi_driver: scmi_driver structure
436  *
437  * Helper macro for scmi drivers to set up proper module init / exit
438  * functions.  Replaces module_init() and module_exit() and keeps people from
439  * printing pointless things to the kernel log when their driver is loaded.
440  */
441 #define module_scmi_driver(__scmi_driver)	\
442 	module_driver(__scmi_driver, scmi_register, scmi_unregister)
443 
444 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
445 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
446 void scmi_protocol_unregister(int protocol_id);
447 
448 /* SCMI Notification API - Custom Event Reports */
449 enum scmi_notification_events {
450 	SCMI_EVENT_POWER_STATE_CHANGED = 0x0,
451 	SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0,
452 	SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1,
453 	SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0,
454 	SCMI_EVENT_RESET_ISSUED = 0x0,
455 	SCMI_EVENT_BASE_ERROR_EVENT = 0x0,
456 	SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER = 0x0,
457 };
458 
459 struct scmi_power_state_changed_report {
460 	ktime_t		timestamp;
461 	unsigned int	agent_id;
462 	unsigned int	domain_id;
463 	unsigned int	power_state;
464 };
465 
466 struct scmi_system_power_state_notifier_report {
467 	ktime_t		timestamp;
468 	unsigned int	agent_id;
469 	unsigned int	flags;
470 	unsigned int	system_state;
471 };
472 
473 struct scmi_perf_limits_report {
474 	ktime_t		timestamp;
475 	unsigned int	agent_id;
476 	unsigned int	domain_id;
477 	unsigned int	range_max;
478 	unsigned int	range_min;
479 };
480 
481 struct scmi_perf_level_report {
482 	ktime_t		timestamp;
483 	unsigned int	agent_id;
484 	unsigned int	domain_id;
485 	unsigned int	performance_level;
486 };
487 
488 struct scmi_sensor_trip_point_report {
489 	ktime_t		timestamp;
490 	unsigned int	agent_id;
491 	unsigned int	sensor_id;
492 	unsigned int	trip_point_desc;
493 };
494 
495 struct scmi_reset_issued_report {
496 	ktime_t		timestamp;
497 	unsigned int	agent_id;
498 	unsigned int	domain_id;
499 	unsigned int	reset_state;
500 };
501 
502 struct scmi_base_error_report {
503 	ktime_t			timestamp;
504 	unsigned int		agent_id;
505 	bool			fatal;
506 	unsigned int		cmd_count;
507 	unsigned long long	reports[];
508 };
509 
510 #endif /* _LINUX_SCMI_PROTOCOL_H */
511