xref: /openbmc/linux/include/linux/scmi_protocol.h (revision 37744fee)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * SCMI Message Protocol driver header
4  *
5  * Copyright (C) 2018 ARM Ltd.
6  */
7 #include <linux/device.h>
8 #include <linux/types.h>
9 
10 #define SCMI_MAX_STR_SIZE	16
11 #define SCMI_MAX_NUM_RATES	16
12 
13 /**
14  * struct scmi_revision_info - version information structure
15  *
16  * @major_ver: Major ABI version. Change here implies risk of backward
17  *	compatibility break.
18  * @minor_ver: Minor ABI version. Change here implies new feature addition,
19  *	or compatible change in ABI.
20  * @num_protocols: Number of protocols that are implemented, excluding the
21  *	base protocol.
22  * @num_agents: Number of agents in the system.
23  * @impl_ver: A vendor-specific implementation version.
24  * @vendor_id: A vendor identifier(Null terminated ASCII string)
25  * @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
26  */
27 struct scmi_revision_info {
28 	u16 major_ver;
29 	u16 minor_ver;
30 	u8 num_protocols;
31 	u8 num_agents;
32 	u32 impl_ver;
33 	char vendor_id[SCMI_MAX_STR_SIZE];
34 	char sub_vendor_id[SCMI_MAX_STR_SIZE];
35 };
36 
37 struct scmi_clock_info {
38 	char name[SCMI_MAX_STR_SIZE];
39 	bool rate_discrete;
40 	union {
41 		struct {
42 			int num_rates;
43 			u64 rates[SCMI_MAX_NUM_RATES];
44 		} list;
45 		struct {
46 			u64 min_rate;
47 			u64 max_rate;
48 			u64 step_size;
49 		} range;
50 	};
51 };
52 
53 struct scmi_handle;
54 
55 /**
56  * struct scmi_clk_ops - represents the various operations provided
57  *	by SCMI Clock Protocol
58  *
59  * @count_get: get the count of clocks provided by SCMI
60  * @info_get: get the information of the specified clock
61  * @rate_get: request the current clock rate of a clock
62  * @rate_set: set the clock rate of a clock
63  * @enable: enables the specified clock
64  * @disable: disables the specified clock
65  */
66 struct scmi_clk_ops {
67 	int (*count_get)(const struct scmi_handle *handle);
68 
69 	const struct scmi_clock_info *(*info_get)
70 		(const struct scmi_handle *handle, u32 clk_id);
71 	int (*rate_get)(const struct scmi_handle *handle, u32 clk_id,
72 			u64 *rate);
73 	int (*rate_set)(const struct scmi_handle *handle, u32 clk_id,
74 			u64 rate);
75 	int (*enable)(const struct scmi_handle *handle, u32 clk_id);
76 	int (*disable)(const struct scmi_handle *handle, u32 clk_id);
77 };
78 
79 /**
80  * struct scmi_perf_ops - represents the various operations provided
81  *	by SCMI Performance Protocol
82  *
83  * @limits_set: sets limits on the performance level of a domain
84  * @limits_get: gets limits on the performance level of a domain
85  * @level_set: sets the performance level of a domain
86  * @level_get: gets the performance level of a domain
87  * @device_domain_id: gets the scmi domain id for a given device
88  * @transition_latency_get: gets the DVFS transition latency for a given device
89  * @device_opps_add: adds all the OPPs for a given device
90  * @freq_set: sets the frequency for a given device using sustained frequency
91  *	to sustained performance level mapping
92  * @freq_get: gets the frequency for a given device using sustained frequency
93  *	to sustained performance level mapping
94  * @est_power_get: gets the estimated power cost for a given performance domain
95  *	at a given frequency
96  */
97 struct scmi_perf_ops {
98 	int (*limits_set)(const struct scmi_handle *handle, u32 domain,
99 			  u32 max_perf, u32 min_perf);
100 	int (*limits_get)(const struct scmi_handle *handle, u32 domain,
101 			  u32 *max_perf, u32 *min_perf);
102 	int (*level_set)(const struct scmi_handle *handle, u32 domain,
103 			 u32 level, bool poll);
104 	int (*level_get)(const struct scmi_handle *handle, u32 domain,
105 			 u32 *level, bool poll);
106 	int (*device_domain_id)(struct device *dev);
107 	int (*transition_latency_get)(const struct scmi_handle *handle,
108 				      struct device *dev);
109 	int (*device_opps_add)(const struct scmi_handle *handle,
110 			       struct device *dev);
111 	int (*freq_set)(const struct scmi_handle *handle, u32 domain,
112 			unsigned long rate, bool poll);
113 	int (*freq_get)(const struct scmi_handle *handle, u32 domain,
114 			unsigned long *rate, bool poll);
115 	int (*est_power_get)(const struct scmi_handle *handle, u32 domain,
116 			     unsigned long *rate, unsigned long *power);
117 };
118 
119 /**
120  * struct scmi_power_ops - represents the various operations provided
121  *	by SCMI Power Protocol
122  *
123  * @num_domains_get: get the count of power domains provided by SCMI
124  * @name_get: gets the name of a power domain
125  * @state_set: sets the power state of a power domain
126  * @state_get: gets the power state of a power domain
127  */
128 struct scmi_power_ops {
129 	int (*num_domains_get)(const struct scmi_handle *handle);
130 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
131 #define SCMI_POWER_STATE_TYPE_SHIFT	30
132 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
133 #define SCMI_POWER_STATE_PARAM(type, id) \
134 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
135 		((id) & SCMI_POWER_STATE_ID_MASK))
136 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
137 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
138 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
139 			 u32 state);
140 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
141 			 u32 *state);
142 };
143 
144 struct scmi_sensor_info {
145 	u32 id;
146 	u8 type;
147 	s8 scale;
148 	u8 num_trip_points;
149 	bool async;
150 	char name[SCMI_MAX_STR_SIZE];
151 };
152 
153 /*
154  * Partial list from Distributed Management Task Force (DMTF) specification:
155  * DSP0249 (Platform Level Data Model specification)
156  */
157 enum scmi_sensor_class {
158 	NONE = 0x0,
159 	TEMPERATURE_C = 0x2,
160 	VOLTAGE = 0x5,
161 	CURRENT = 0x6,
162 	POWER = 0x7,
163 	ENERGY = 0x8,
164 };
165 
166 /**
167  * struct scmi_sensor_ops - represents the various operations provided
168  *	by SCMI Sensor Protocol
169  *
170  * @count_get: get the count of sensors provided by SCMI
171  * @info_get: get the information of the specified sensor
172  * @trip_point_notify: control notifications on cross-over events for
173  *	the trip-points
174  * @trip_point_config: selects and configures a trip-point of interest
175  * @reading_get: gets the current value of the sensor
176  */
177 struct scmi_sensor_ops {
178 	int (*count_get)(const struct scmi_handle *handle);
179 
180 	const struct scmi_sensor_info *(*info_get)
181 		(const struct scmi_handle *handle, u32 sensor_id);
182 	int (*trip_point_notify)(const struct scmi_handle *handle,
183 				 u32 sensor_id, bool enable);
184 	int (*trip_point_config)(const struct scmi_handle *handle,
185 				 u32 sensor_id, u8 trip_id, u64 trip_value);
186 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
187 			   u64 *value);
188 };
189 
190 /**
191  * struct scmi_reset_ops - represents the various operations provided
192  *	by SCMI Reset Protocol
193  *
194  * @num_domains_get: get the count of reset domains provided by SCMI
195  * @name_get: gets the name of a reset domain
196  * @latency_get: gets the reset latency for the specified reset domain
197  * @reset: resets the specified reset domain
198  * @assert: explicitly assert reset signal of the specified reset domain
199  * @deassert: explicitly deassert reset signal of the specified reset domain
200  */
201 struct scmi_reset_ops {
202 	int (*num_domains_get)(const struct scmi_handle *handle);
203 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
204 	int (*latency_get)(const struct scmi_handle *handle, u32 domain);
205 	int (*reset)(const struct scmi_handle *handle, u32 domain);
206 	int (*assert)(const struct scmi_handle *handle, u32 domain);
207 	int (*deassert)(const struct scmi_handle *handle, u32 domain);
208 };
209 
210 /**
211  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
212  *
213  * @dev: pointer to the SCMI device
214  * @version: pointer to the structure containing SCMI version information
215  * @power_ops: pointer to set of power protocol operations
216  * @perf_ops: pointer to set of performance protocol operations
217  * @clk_ops: pointer to set of clock protocol operations
218  * @sensor_ops: pointer to set of sensor protocol operations
219  * @reset_ops: pointer to set of reset protocol operations
220  * @perf_priv: pointer to private data structure specific to performance
221  *	protocol(for internal use only)
222  * @clk_priv: pointer to private data structure specific to clock
223  *	protocol(for internal use only)
224  * @power_priv: pointer to private data structure specific to power
225  *	protocol(for internal use only)
226  * @sensor_priv: pointer to private data structure specific to sensors
227  *	protocol(for internal use only)
228  * @reset_priv: pointer to private data structure specific to reset
229  *	protocol(for internal use only)
230  */
231 struct scmi_handle {
232 	struct device *dev;
233 	struct scmi_revision_info *version;
234 	struct scmi_perf_ops *perf_ops;
235 	struct scmi_clk_ops *clk_ops;
236 	struct scmi_power_ops *power_ops;
237 	struct scmi_sensor_ops *sensor_ops;
238 	struct scmi_reset_ops *reset_ops;
239 	/* for protocol internal use */
240 	void *perf_priv;
241 	void *clk_priv;
242 	void *power_priv;
243 	void *sensor_priv;
244 	void *reset_priv;
245 };
246 
247 enum scmi_std_protocol {
248 	SCMI_PROTOCOL_BASE = 0x10,
249 	SCMI_PROTOCOL_POWER = 0x11,
250 	SCMI_PROTOCOL_SYSTEM = 0x12,
251 	SCMI_PROTOCOL_PERF = 0x13,
252 	SCMI_PROTOCOL_CLOCK = 0x14,
253 	SCMI_PROTOCOL_SENSOR = 0x15,
254 	SCMI_PROTOCOL_RESET = 0x16,
255 };
256 
257 struct scmi_device {
258 	u32 id;
259 	u8 protocol_id;
260 	const char *name;
261 	struct device dev;
262 	struct scmi_handle *handle;
263 };
264 
265 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
266 
267 struct scmi_device *
268 scmi_device_create(struct device_node *np, struct device *parent, int protocol,
269 		   const char *name);
270 void scmi_device_destroy(struct scmi_device *scmi_dev);
271 
272 struct scmi_device_id {
273 	u8 protocol_id;
274 	const char *name;
275 };
276 
277 struct scmi_driver {
278 	const char *name;
279 	int (*probe)(struct scmi_device *sdev);
280 	void (*remove)(struct scmi_device *sdev);
281 	const struct scmi_device_id *id_table;
282 
283 	struct device_driver driver;
284 };
285 
286 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
287 
288 #ifdef CONFIG_ARM_SCMI_PROTOCOL
289 int scmi_driver_register(struct scmi_driver *driver,
290 			 struct module *owner, const char *mod_name);
291 void scmi_driver_unregister(struct scmi_driver *driver);
292 #else
293 static inline int
294 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
295 		     const char *mod_name)
296 {
297 	return -EINVAL;
298 }
299 
300 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
301 #endif /* CONFIG_ARM_SCMI_PROTOCOL */
302 
303 #define scmi_register(driver) \
304 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
305 #define scmi_unregister(driver) \
306 	scmi_driver_unregister(driver)
307 
308 /**
309  * module_scmi_driver() - Helper macro for registering a scmi driver
310  * @__scmi_driver: scmi_driver structure
311  *
312  * Helper macro for scmi drivers to set up proper module init / exit
313  * functions.  Replaces module_init() and module_exit() and keeps people from
314  * printing pointless things to the kernel log when their driver is loaded.
315  */
316 #define module_scmi_driver(__scmi_driver)	\
317 	module_driver(__scmi_driver, scmi_register, scmi_unregister)
318 
319 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
320 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
321 void scmi_protocol_unregister(int protocol_id);
322