xref: /openbmc/linux/include/linux/scmi_protocol.h (revision 7c768f84)
1 // SPDX-License-Identifier: GPL-2.0
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 			u32 config, 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  */
95 struct scmi_perf_ops {
96 	int (*limits_set)(const struct scmi_handle *handle, u32 domain,
97 			  u32 max_perf, u32 min_perf);
98 	int (*limits_get)(const struct scmi_handle *handle, u32 domain,
99 			  u32 *max_perf, u32 *min_perf);
100 	int (*level_set)(const struct scmi_handle *handle, u32 domain,
101 			 u32 level, bool poll);
102 	int (*level_get)(const struct scmi_handle *handle, u32 domain,
103 			 u32 *level, bool poll);
104 	int (*device_domain_id)(struct device *dev);
105 	int (*transition_latency_get)(const struct scmi_handle *handle,
106 				      struct device *dev);
107 	int (*device_opps_add)(const struct scmi_handle *handle,
108 			       struct device *dev);
109 	int (*freq_set)(const struct scmi_handle *handle, u32 domain,
110 			unsigned long rate, bool poll);
111 	int (*freq_get)(const struct scmi_handle *handle, u32 domain,
112 			unsigned long *rate, bool poll);
113 };
114 
115 /**
116  * struct scmi_power_ops - represents the various operations provided
117  *	by SCMI Power Protocol
118  *
119  * @num_domains_get: get the count of power domains provided by SCMI
120  * @name_get: gets the name of a power domain
121  * @state_set: sets the power state of a power domain
122  * @state_get: gets the power state of a power domain
123  */
124 struct scmi_power_ops {
125 	int (*num_domains_get)(const struct scmi_handle *handle);
126 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
127 #define SCMI_POWER_STATE_TYPE_SHIFT	30
128 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
129 #define SCMI_POWER_STATE_PARAM(type, id) \
130 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
131 		((id) & SCMI_POWER_STATE_ID_MASK))
132 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
133 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
134 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
135 			 u32 state);
136 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
137 			 u32 *state);
138 };
139 
140 struct scmi_sensor_info {
141 	u32 id;
142 	u8 type;
143 	char name[SCMI_MAX_STR_SIZE];
144 };
145 
146 /*
147  * Partial list from Distributed Management Task Force (DMTF) specification:
148  * DSP0249 (Platform Level Data Model specification)
149  */
150 enum scmi_sensor_class {
151 	NONE = 0x0,
152 	TEMPERATURE_C = 0x2,
153 	VOLTAGE = 0x5,
154 	CURRENT = 0x6,
155 	POWER = 0x7,
156 	ENERGY = 0x8,
157 };
158 
159 /**
160  * struct scmi_sensor_ops - represents the various operations provided
161  *	by SCMI Sensor Protocol
162  *
163  * @count_get: get the count of sensors provided by SCMI
164  * @info_get: get the information of the specified sensor
165  * @configuration_set: control notifications on cross-over events for
166  *	the trip-points
167  * @trip_point_set: selects and configures a trip-point of interest
168  * @reading_get: gets the current value of the sensor
169  */
170 struct scmi_sensor_ops {
171 	int (*count_get)(const struct scmi_handle *handle);
172 
173 	const struct scmi_sensor_info *(*info_get)
174 		(const struct scmi_handle *handle, u32 sensor_id);
175 	int (*configuration_set)(const struct scmi_handle *handle,
176 				 u32 sensor_id);
177 	int (*trip_point_set)(const struct scmi_handle *handle, u32 sensor_id,
178 			      u8 trip_id, u64 trip_value);
179 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
180 			   bool async, u64 *value);
181 };
182 
183 /**
184  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
185  *
186  * @dev: pointer to the SCMI device
187  * @version: pointer to the structure containing SCMI version information
188  * @power_ops: pointer to set of power protocol operations
189  * @perf_ops: pointer to set of performance protocol operations
190  * @clk_ops: pointer to set of clock protocol operations
191  * @sensor_ops: pointer to set of sensor protocol operations
192  * @perf_priv: pointer to private data structure specific to performance
193  *	protocol(for internal use only)
194  * @clk_priv: pointer to private data structure specific to clock
195  *	protocol(for internal use only)
196  * @power_priv: pointer to private data structure specific to power
197  *	protocol(for internal use only)
198  * @sensor_priv: pointer to private data structure specific to sensors
199  *	protocol(for internal use only)
200  */
201 struct scmi_handle {
202 	struct device *dev;
203 	struct scmi_revision_info *version;
204 	struct scmi_perf_ops *perf_ops;
205 	struct scmi_clk_ops *clk_ops;
206 	struct scmi_power_ops *power_ops;
207 	struct scmi_sensor_ops *sensor_ops;
208 	/* for protocol internal use */
209 	void *perf_priv;
210 	void *clk_priv;
211 	void *power_priv;
212 	void *sensor_priv;
213 };
214 
215 enum scmi_std_protocol {
216 	SCMI_PROTOCOL_BASE = 0x10,
217 	SCMI_PROTOCOL_POWER = 0x11,
218 	SCMI_PROTOCOL_SYSTEM = 0x12,
219 	SCMI_PROTOCOL_PERF = 0x13,
220 	SCMI_PROTOCOL_CLOCK = 0x14,
221 	SCMI_PROTOCOL_SENSOR = 0x15,
222 };
223 
224 struct scmi_device {
225 	u32 id;
226 	u8 protocol_id;
227 	struct device dev;
228 	struct scmi_handle *handle;
229 };
230 
231 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)
232 
233 struct scmi_device *
234 scmi_device_create(struct device_node *np, struct device *parent, int protocol);
235 void scmi_device_destroy(struct scmi_device *scmi_dev);
236 
237 struct scmi_device_id {
238 	u8 protocol_id;
239 };
240 
241 struct scmi_driver {
242 	const char *name;
243 	int (*probe)(struct scmi_device *sdev);
244 	void (*remove)(struct scmi_device *sdev);
245 	const struct scmi_device_id *id_table;
246 
247 	struct device_driver driver;
248 };
249 
250 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)
251 
252 #ifdef CONFIG_ARM_SCMI_PROTOCOL
253 int scmi_driver_register(struct scmi_driver *driver,
254 			 struct module *owner, const char *mod_name);
255 void scmi_driver_unregister(struct scmi_driver *driver);
256 #else
257 static inline int
258 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
259 		     const char *mod_name)
260 {
261 	return -EINVAL;
262 }
263 
264 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
265 #endif /* CONFIG_ARM_SCMI_PROTOCOL */
266 
267 #define scmi_register(driver) \
268 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
269 #define scmi_unregister(driver) \
270 	scmi_driver_unregister(driver)
271 
272 /**
273  * module_scmi_driver() - Helper macro for registering a scmi driver
274  * @__scmi_driver: scmi_driver structure
275  *
276  * Helper macro for scmi drivers to set up proper module init / exit
277  * functions.  Replaces module_init() and module_exit() and keeps people from
278  * printing pointless things to the kernel log when their driver is loaded.
279  */
280 #define module_scmi_driver(__scmi_driver)	\
281 	module_driver(__scmi_driver, scmi_register, scmi_unregister)
282 
283 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
284 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
285 void scmi_protocol_unregister(int protocol_id);
286