xref: /openbmc/linux/include/linux/scmi_protocol.h (revision 82df5b73)
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/types.h>
13 
14 #define SCMI_MAX_STR_SIZE	16
15 #define SCMI_MAX_NUM_RATES	16
16 
17 /**
18  * struct scmi_revision_info - version information structure
19  *
20  * @major_ver: Major ABI version. Change here implies risk of backward
21  *	compatibility break.
22  * @minor_ver: Minor ABI version. Change here implies new feature addition,
23  *	or compatible change in ABI.
24  * @num_protocols: Number of protocols that are implemented, excluding the
25  *	base protocol.
26  * @num_agents: Number of agents in the system.
27  * @impl_ver: A vendor-specific implementation version.
28  * @vendor_id: A vendor identifier(Null terminated ASCII string)
29  * @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
30  */
31 struct scmi_revision_info {
32 	u16 major_ver;
33 	u16 minor_ver;
34 	u8 num_protocols;
35 	u8 num_agents;
36 	u32 impl_ver;
37 	char vendor_id[SCMI_MAX_STR_SIZE];
38 	char sub_vendor_id[SCMI_MAX_STR_SIZE];
39 };
40 
41 struct scmi_clock_info {
42 	char name[SCMI_MAX_STR_SIZE];
43 	bool rate_discrete;
44 	union {
45 		struct {
46 			int num_rates;
47 			u64 rates[SCMI_MAX_NUM_RATES];
48 		} list;
49 		struct {
50 			u64 min_rate;
51 			u64 max_rate;
52 			u64 step_size;
53 		} range;
54 	};
55 };
56 
57 struct scmi_handle;
58 
59 /**
60  * struct scmi_clk_ops - represents the various operations provided
61  *	by SCMI Clock Protocol
62  *
63  * @count_get: get the count of clocks provided by SCMI
64  * @info_get: get the information of the specified clock
65  * @rate_get: request the current clock rate of a clock
66  * @rate_set: set the clock rate of a clock
67  * @enable: enables the specified clock
68  * @disable: disables the specified clock
69  */
70 struct scmi_clk_ops {
71 	int (*count_get)(const struct scmi_handle *handle);
72 
73 	const struct scmi_clock_info *(*info_get)
74 		(const struct scmi_handle *handle, u32 clk_id);
75 	int (*rate_get)(const struct scmi_handle *handle, u32 clk_id,
76 			u64 *rate);
77 	int (*rate_set)(const struct scmi_handle *handle, u32 clk_id,
78 			u64 rate);
79 	int (*enable)(const struct scmi_handle *handle, u32 clk_id);
80 	int (*disable)(const struct scmi_handle *handle, u32 clk_id);
81 };
82 
83 /**
84  * struct scmi_perf_ops - represents the various operations provided
85  *	by SCMI Performance Protocol
86  *
87  * @limits_set: sets limits on the performance level of a domain
88  * @limits_get: gets limits on the performance level of a domain
89  * @level_set: sets the performance level of a domain
90  * @level_get: gets the performance level of a domain
91  * @device_domain_id: gets the scmi domain id for a given device
92  * @transition_latency_get: gets the DVFS transition latency for a given device
93  * @device_opps_add: adds all the OPPs for a given device
94  * @freq_set: sets the frequency for a given device using sustained frequency
95  *	to sustained performance level mapping
96  * @freq_get: gets the frequency for a given device using sustained frequency
97  *	to sustained performance level mapping
98  * @est_power_get: gets the estimated power cost for a given performance domain
99  *	at a given frequency
100  */
101 struct scmi_perf_ops {
102 	int (*limits_set)(const struct scmi_handle *handle, u32 domain,
103 			  u32 max_perf, u32 min_perf);
104 	int (*limits_get)(const struct scmi_handle *handle, u32 domain,
105 			  u32 *max_perf, u32 *min_perf);
106 	int (*level_set)(const struct scmi_handle *handle, u32 domain,
107 			 u32 level, bool poll);
108 	int (*level_get)(const struct scmi_handle *handle, u32 domain,
109 			 u32 *level, bool poll);
110 	int (*device_domain_id)(struct device *dev);
111 	int (*transition_latency_get)(const struct scmi_handle *handle,
112 				      struct device *dev);
113 	int (*device_opps_add)(const struct scmi_handle *handle,
114 			       struct device *dev);
115 	int (*freq_set)(const struct scmi_handle *handle, u32 domain,
116 			unsigned long rate, bool poll);
117 	int (*freq_get)(const struct scmi_handle *handle, u32 domain,
118 			unsigned long *rate, bool poll);
119 	int (*est_power_get)(const struct scmi_handle *handle, u32 domain,
120 			     unsigned long *rate, unsigned long *power);
121 };
122 
123 /**
124  * struct scmi_power_ops - represents the various operations provided
125  *	by SCMI Power Protocol
126  *
127  * @num_domains_get: get the count of power domains provided by SCMI
128  * @name_get: gets the name of a power domain
129  * @state_set: sets the power state of a power domain
130  * @state_get: gets the power state of a power domain
131  */
132 struct scmi_power_ops {
133 	int (*num_domains_get)(const struct scmi_handle *handle);
134 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
135 #define SCMI_POWER_STATE_TYPE_SHIFT	30
136 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
137 #define SCMI_POWER_STATE_PARAM(type, id) \
138 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
139 		((id) & SCMI_POWER_STATE_ID_MASK))
140 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
141 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
142 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
143 			 u32 state);
144 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
145 			 u32 *state);
146 };
147 
148 struct scmi_sensor_info {
149 	u32 id;
150 	u8 type;
151 	s8 scale;
152 	u8 num_trip_points;
153 	bool async;
154 	char name[SCMI_MAX_STR_SIZE];
155 };
156 
157 /*
158  * Partial list from Distributed Management Task Force (DMTF) specification:
159  * DSP0249 (Platform Level Data Model specification)
160  */
161 enum scmi_sensor_class {
162 	NONE = 0x0,
163 	TEMPERATURE_C = 0x2,
164 	VOLTAGE = 0x5,
165 	CURRENT = 0x6,
166 	POWER = 0x7,
167 	ENERGY = 0x8,
168 };
169 
170 /**
171  * struct scmi_sensor_ops - represents the various operations provided
172  *	by SCMI Sensor Protocol
173  *
174  * @count_get: get the count of sensors provided by SCMI
175  * @info_get: get the information of the specified sensor
176  * @trip_point_notify: control notifications on cross-over events for
177  *	the trip-points
178  * @trip_point_config: selects and configures a trip-point of interest
179  * @reading_get: gets the current value of the sensor
180  */
181 struct scmi_sensor_ops {
182 	int (*count_get)(const struct scmi_handle *handle);
183 
184 	const struct scmi_sensor_info *(*info_get)
185 		(const struct scmi_handle *handle, u32 sensor_id);
186 	int (*trip_point_notify)(const struct scmi_handle *handle,
187 				 u32 sensor_id, bool enable);
188 	int (*trip_point_config)(const struct scmi_handle *handle,
189 				 u32 sensor_id, u8 trip_id, u64 trip_value);
190 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
191 			   u64 *value);
192 };
193 
194 /**
195  * struct scmi_reset_ops - represents the various operations provided
196  *	by SCMI Reset Protocol
197  *
198  * @num_domains_get: get the count of reset domains provided by SCMI
199  * @name_get: gets the name of a reset domain
200  * @latency_get: gets the reset latency for the specified reset domain
201  * @reset: resets the specified reset domain
202  * @assert: explicitly assert reset signal of the specified reset domain
203  * @deassert: explicitly deassert reset signal of the specified reset domain
204  */
205 struct scmi_reset_ops {
206 	int (*num_domains_get)(const struct scmi_handle *handle);
207 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
208 	int (*latency_get)(const struct scmi_handle *handle, u32 domain);
209 	int (*reset)(const struct scmi_handle *handle, u32 domain);
210 	int (*assert)(const struct scmi_handle *handle, u32 domain);
211 	int (*deassert)(const struct scmi_handle *handle, u32 domain);
212 };
213 
214 /**
215  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
216  *
217  * @dev: pointer to the SCMI device
218  * @version: pointer to the structure containing SCMI version information
219  * @power_ops: pointer to set of power protocol operations
220  * @perf_ops: pointer to set of performance protocol operations
221  * @clk_ops: pointer to set of clock protocol operations
222  * @sensor_ops: pointer to set of sensor protocol operations
223  * @reset_ops: pointer to set of reset protocol operations
224  * @perf_priv: pointer to private data structure specific to performance
225  *	protocol(for internal use only)
226  * @clk_priv: pointer to private data structure specific to clock
227  *	protocol(for internal use only)
228  * @power_priv: pointer to private data structure specific to power
229  *	protocol(for internal use only)
230  * @sensor_priv: pointer to private data structure specific to sensors
231  *	protocol(for internal use only)
232  * @reset_priv: pointer to private data structure specific to reset
233  *	protocol(for internal use only)
234  */
235 struct scmi_handle {
236 	struct device *dev;
237 	struct scmi_revision_info *version;
238 	struct scmi_perf_ops *perf_ops;
239 	struct scmi_clk_ops *clk_ops;
240 	struct scmi_power_ops *power_ops;
241 	struct scmi_sensor_ops *sensor_ops;
242 	struct scmi_reset_ops *reset_ops;
243 	/* for protocol internal use */
244 	void *perf_priv;
245 	void *clk_priv;
246 	void *power_priv;
247 	void *sensor_priv;
248 	void *reset_priv;
249 };
250 
251 enum scmi_std_protocol {
252 	SCMI_PROTOCOL_BASE = 0x10,
253 	SCMI_PROTOCOL_POWER = 0x11,
254 	SCMI_PROTOCOL_SYSTEM = 0x12,
255 	SCMI_PROTOCOL_PERF = 0x13,
256 	SCMI_PROTOCOL_CLOCK = 0x14,
257 	SCMI_PROTOCOL_SENSOR = 0x15,
258 	SCMI_PROTOCOL_RESET = 0x16,
259 };
260 
261 struct scmi_device {
262 	u32 id;
263 	u8 protocol_id;
264 	const char *name;
265 	struct device dev;
266 	struct scmi_handle *handle;
267 };
268 
269 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
270 
271 struct scmi_device *
272 scmi_device_create(struct device_node *np, struct device *parent, int protocol,
273 		   const char *name);
274 void scmi_device_destroy(struct scmi_device *scmi_dev);
275 
276 struct scmi_device_id {
277 	u8 protocol_id;
278 	const char *name;
279 };
280 
281 struct scmi_driver {
282 	const char *name;
283 	int (*probe)(struct scmi_device *sdev);
284 	void (*remove)(struct scmi_device *sdev);
285 	const struct scmi_device_id *id_table;
286 
287 	struct device_driver driver;
288 };
289 
290 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
291 
292 #ifdef CONFIG_ARM_SCMI_PROTOCOL
293 int scmi_driver_register(struct scmi_driver *driver,
294 			 struct module *owner, const char *mod_name);
295 void scmi_driver_unregister(struct scmi_driver *driver);
296 #else
297 static inline int
298 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
299 		     const char *mod_name)
300 {
301 	return -EINVAL;
302 }
303 
304 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
305 #endif /* CONFIG_ARM_SCMI_PROTOCOL */
306 
307 #define scmi_register(driver) \
308 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
309 #define scmi_unregister(driver) \
310 	scmi_driver_unregister(driver)
311 
312 /**
313  * module_scmi_driver() - Helper macro for registering a scmi driver
314  * @__scmi_driver: scmi_driver structure
315  *
316  * Helper macro for scmi drivers to set up proper module init / exit
317  * functions.  Replaces module_init() and module_exit() and keeps people from
318  * printing pointless things to the kernel log when their driver is loaded.
319  */
320 #define module_scmi_driver(__scmi_driver)	\
321 	module_driver(__scmi_driver, scmi_register, scmi_unregister)
322 
323 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
324 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
325 void scmi_protocol_unregister(int protocol_id);
326 
327 #endif /* _LINUX_SCMI_PROTOCOL_H */
328