1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * System Control and Management Interface (SCMI) Sensor Protocol
4  *
5  * Copyright (C) 2018 ARM Ltd.
6  */
7 
8 #define pr_fmt(fmt) "SCMI Notifications SENSOR - " fmt
9 
10 #include <linux/scmi_protocol.h>
11 
12 #include "common.h"
13 #include "notify.h"
14 
15 enum scmi_sensor_protocol_cmd {
16 	SENSOR_DESCRIPTION_GET = 0x3,
17 	SENSOR_TRIP_POINT_NOTIFY = 0x4,
18 	SENSOR_TRIP_POINT_CONFIG = 0x5,
19 	SENSOR_READING_GET = 0x6,
20 };
21 
22 struct scmi_msg_resp_sensor_attributes {
23 	__le16 num_sensors;
24 	u8 max_requests;
25 	u8 reserved;
26 	__le32 reg_addr_low;
27 	__le32 reg_addr_high;
28 	__le32 reg_size;
29 };
30 
31 struct scmi_msg_resp_sensor_description {
32 	__le16 num_returned;
33 	__le16 num_remaining;
34 	struct {
35 		__le32 id;
36 		__le32 attributes_low;
37 #define SUPPORTS_ASYNC_READ(x)	((x) & BIT(31))
38 #define NUM_TRIP_POINTS(x)	((x) & 0xff)
39 		__le32 attributes_high;
40 #define SENSOR_TYPE(x)		((x) & 0xff)
41 #define SENSOR_SCALE(x)		(((x) >> 11) & 0x1f)
42 #define SENSOR_SCALE_SIGN	BIT(4)
43 #define SENSOR_SCALE_EXTEND	GENMASK(7, 5)
44 #define SENSOR_UPDATE_SCALE(x)	(((x) >> 22) & 0x1f)
45 #define SENSOR_UPDATE_BASE(x)	(((x) >> 27) & 0x1f)
46 		    u8 name[SCMI_MAX_STR_SIZE];
47 	} desc[0];
48 };
49 
50 struct scmi_msg_sensor_trip_point_notify {
51 	__le32 id;
52 	__le32 event_control;
53 #define SENSOR_TP_NOTIFY_ALL	BIT(0)
54 };
55 
56 struct scmi_msg_set_sensor_trip_point {
57 	__le32 id;
58 	__le32 event_control;
59 #define SENSOR_TP_EVENT_MASK	(0x3)
60 #define SENSOR_TP_DISABLED	0x0
61 #define SENSOR_TP_POSITIVE	0x1
62 #define SENSOR_TP_NEGATIVE	0x2
63 #define SENSOR_TP_BOTH		0x3
64 #define SENSOR_TP_ID(x)		(((x) & 0xff) << 4)
65 	__le32 value_low;
66 	__le32 value_high;
67 };
68 
69 struct scmi_msg_sensor_reading_get {
70 	__le32 id;
71 	__le32 flags;
72 #define SENSOR_READ_ASYNC	BIT(0)
73 };
74 
75 struct scmi_sensor_trip_notify_payld {
76 	__le32 agent_id;
77 	__le32 sensor_id;
78 	__le32 trip_point_desc;
79 };
80 
81 struct sensors_info {
82 	u32 version;
83 	int num_sensors;
84 	int max_requests;
85 	u64 reg_addr;
86 	u32 reg_size;
87 	struct scmi_sensor_info *sensors;
88 };
89 
90 static int scmi_sensor_attributes_get(const struct scmi_handle *handle,
91 				      struct sensors_info *si)
92 {
93 	int ret;
94 	struct scmi_xfer *t;
95 	struct scmi_msg_resp_sensor_attributes *attr;
96 
97 	ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
98 				 SCMI_PROTOCOL_SENSOR, 0, sizeof(*attr), &t);
99 	if (ret)
100 		return ret;
101 
102 	attr = t->rx.buf;
103 
104 	ret = scmi_do_xfer(handle, t);
105 	if (!ret) {
106 		si->num_sensors = le16_to_cpu(attr->num_sensors);
107 		si->max_requests = attr->max_requests;
108 		si->reg_addr = le32_to_cpu(attr->reg_addr_low) |
109 				(u64)le32_to_cpu(attr->reg_addr_high) << 32;
110 		si->reg_size = le32_to_cpu(attr->reg_size);
111 	}
112 
113 	scmi_xfer_put(handle, t);
114 	return ret;
115 }
116 
117 static int scmi_sensor_description_get(const struct scmi_handle *handle,
118 				       struct sensors_info *si)
119 {
120 	int ret, cnt;
121 	u32 desc_index = 0;
122 	u16 num_returned, num_remaining;
123 	struct scmi_xfer *t;
124 	struct scmi_msg_resp_sensor_description *buf;
125 
126 	ret = scmi_xfer_get_init(handle, SENSOR_DESCRIPTION_GET,
127 				 SCMI_PROTOCOL_SENSOR, sizeof(__le32), 0, &t);
128 	if (ret)
129 		return ret;
130 
131 	buf = t->rx.buf;
132 
133 	do {
134 		/* Set the number of sensors to be skipped/already read */
135 		put_unaligned_le32(desc_index, t->tx.buf);
136 
137 		ret = scmi_do_xfer(handle, t);
138 		if (ret)
139 			break;
140 
141 		num_returned = le16_to_cpu(buf->num_returned);
142 		num_remaining = le16_to_cpu(buf->num_remaining);
143 
144 		if (desc_index + num_returned > si->num_sensors) {
145 			dev_err(handle->dev, "No. of sensors can't exceed %d",
146 				si->num_sensors);
147 			break;
148 		}
149 
150 		for (cnt = 0; cnt < num_returned; cnt++) {
151 			u32 attrh, attrl;
152 			struct scmi_sensor_info *s;
153 
154 			attrl = le32_to_cpu(buf->desc[cnt].attributes_low);
155 			attrh = le32_to_cpu(buf->desc[cnt].attributes_high);
156 			s = &si->sensors[desc_index + cnt];
157 			s->id = le32_to_cpu(buf->desc[cnt].id);
158 			s->type = SENSOR_TYPE(attrh);
159 			s->scale = SENSOR_SCALE(attrh);
160 			/* Sign extend to a full s8 */
161 			if (s->scale & SENSOR_SCALE_SIGN)
162 				s->scale |= SENSOR_SCALE_EXTEND;
163 			s->async = SUPPORTS_ASYNC_READ(attrl);
164 			s->num_trip_points = NUM_TRIP_POINTS(attrl);
165 			strlcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
166 		}
167 
168 		desc_index += num_returned;
169 		/*
170 		 * check for both returned and remaining to avoid infinite
171 		 * loop due to buggy firmware
172 		 */
173 	} while (num_returned && num_remaining);
174 
175 	scmi_xfer_put(handle, t);
176 	return ret;
177 }
178 
179 static int scmi_sensor_trip_point_notify(const struct scmi_handle *handle,
180 					 u32 sensor_id, bool enable)
181 {
182 	int ret;
183 	u32 evt_cntl = enable ? SENSOR_TP_NOTIFY_ALL : 0;
184 	struct scmi_xfer *t;
185 	struct scmi_msg_sensor_trip_point_notify *cfg;
186 
187 	ret = scmi_xfer_get_init(handle, SENSOR_TRIP_POINT_NOTIFY,
188 				 SCMI_PROTOCOL_SENSOR, sizeof(*cfg), 0, &t);
189 	if (ret)
190 		return ret;
191 
192 	cfg = t->tx.buf;
193 	cfg->id = cpu_to_le32(sensor_id);
194 	cfg->event_control = cpu_to_le32(evt_cntl);
195 
196 	ret = scmi_do_xfer(handle, t);
197 
198 	scmi_xfer_put(handle, t);
199 	return ret;
200 }
201 
202 static int
203 scmi_sensor_trip_point_config(const struct scmi_handle *handle, u32 sensor_id,
204 			      u8 trip_id, u64 trip_value)
205 {
206 	int ret;
207 	u32 evt_cntl = SENSOR_TP_BOTH;
208 	struct scmi_xfer *t;
209 	struct scmi_msg_set_sensor_trip_point *trip;
210 
211 	ret = scmi_xfer_get_init(handle, SENSOR_TRIP_POINT_CONFIG,
212 				 SCMI_PROTOCOL_SENSOR, sizeof(*trip), 0, &t);
213 	if (ret)
214 		return ret;
215 
216 	trip = t->tx.buf;
217 	trip->id = cpu_to_le32(sensor_id);
218 	trip->event_control = cpu_to_le32(evt_cntl | SENSOR_TP_ID(trip_id));
219 	trip->value_low = cpu_to_le32(trip_value & 0xffffffff);
220 	trip->value_high = cpu_to_le32(trip_value >> 32);
221 
222 	ret = scmi_do_xfer(handle, t);
223 
224 	scmi_xfer_put(handle, t);
225 	return ret;
226 }
227 
228 static int scmi_sensor_reading_get(const struct scmi_handle *handle,
229 				   u32 sensor_id, u64 *value)
230 {
231 	int ret;
232 	struct scmi_xfer *t;
233 	struct scmi_msg_sensor_reading_get *sensor;
234 	struct sensors_info *si = handle->sensor_priv;
235 	struct scmi_sensor_info *s = si->sensors + sensor_id;
236 
237 	ret = scmi_xfer_get_init(handle, SENSOR_READING_GET,
238 				 SCMI_PROTOCOL_SENSOR, sizeof(*sensor),
239 				 sizeof(u64), &t);
240 	if (ret)
241 		return ret;
242 
243 	sensor = t->tx.buf;
244 	sensor->id = cpu_to_le32(sensor_id);
245 
246 	if (s->async) {
247 		sensor->flags = cpu_to_le32(SENSOR_READ_ASYNC);
248 		ret = scmi_do_xfer_with_response(handle, t);
249 		if (!ret)
250 			*value = get_unaligned_le64((void *)
251 						    ((__le32 *)t->rx.buf + 1));
252 	} else {
253 		sensor->flags = cpu_to_le32(0);
254 		ret = scmi_do_xfer(handle, t);
255 		if (!ret)
256 			*value = get_unaligned_le64(t->rx.buf);
257 	}
258 
259 	scmi_xfer_put(handle, t);
260 	return ret;
261 }
262 
263 static const struct scmi_sensor_info *
264 scmi_sensor_info_get(const struct scmi_handle *handle, u32 sensor_id)
265 {
266 	struct sensors_info *si = handle->sensor_priv;
267 
268 	return si->sensors + sensor_id;
269 }
270 
271 static int scmi_sensor_count_get(const struct scmi_handle *handle)
272 {
273 	struct sensors_info *si = handle->sensor_priv;
274 
275 	return si->num_sensors;
276 }
277 
278 static struct scmi_sensor_ops sensor_ops = {
279 	.count_get = scmi_sensor_count_get,
280 	.info_get = scmi_sensor_info_get,
281 	.trip_point_config = scmi_sensor_trip_point_config,
282 	.reading_get = scmi_sensor_reading_get,
283 };
284 
285 static int scmi_sensor_set_notify_enabled(const struct scmi_handle *handle,
286 					  u8 evt_id, u32 src_id, bool enable)
287 {
288 	int ret;
289 
290 	ret = scmi_sensor_trip_point_notify(handle, src_id, enable);
291 	if (ret)
292 		pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
293 			 evt_id, src_id, ret);
294 
295 	return ret;
296 }
297 
298 static void *scmi_sensor_fill_custom_report(const struct scmi_handle *handle,
299 					    u8 evt_id, ktime_t timestamp,
300 					    const void *payld, size_t payld_sz,
301 					    void *report, u32 *src_id)
302 {
303 	const struct scmi_sensor_trip_notify_payld *p = payld;
304 	struct scmi_sensor_trip_point_report *r = report;
305 
306 	if (evt_id != SCMI_EVENT_SENSOR_TRIP_POINT_EVENT ||
307 	    sizeof(*p) != payld_sz)
308 		return NULL;
309 
310 	r->timestamp = timestamp;
311 	r->agent_id = le32_to_cpu(p->agent_id);
312 	r->sensor_id = le32_to_cpu(p->sensor_id);
313 	r->trip_point_desc = le32_to_cpu(p->trip_point_desc);
314 	*src_id = r->sensor_id;
315 
316 	return r;
317 }
318 
319 static const struct scmi_event sensor_events[] = {
320 	{
321 		.id = SCMI_EVENT_SENSOR_TRIP_POINT_EVENT,
322 		.max_payld_sz = sizeof(struct scmi_sensor_trip_notify_payld),
323 		.max_report_sz = sizeof(struct scmi_sensor_trip_point_report),
324 	},
325 };
326 
327 static const struct scmi_event_ops sensor_event_ops = {
328 	.set_notify_enabled = scmi_sensor_set_notify_enabled,
329 	.fill_custom_report = scmi_sensor_fill_custom_report,
330 };
331 
332 static int scmi_sensors_protocol_init(struct scmi_handle *handle)
333 {
334 	u32 version;
335 	struct sensors_info *sinfo;
336 
337 	scmi_version_get(handle, SCMI_PROTOCOL_SENSOR, &version);
338 
339 	dev_dbg(handle->dev, "Sensor Version %d.%d\n",
340 		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
341 
342 	sinfo = devm_kzalloc(handle->dev, sizeof(*sinfo), GFP_KERNEL);
343 	if (!sinfo)
344 		return -ENOMEM;
345 
346 	scmi_sensor_attributes_get(handle, sinfo);
347 
348 	sinfo->sensors = devm_kcalloc(handle->dev, sinfo->num_sensors,
349 				      sizeof(*sinfo->sensors), GFP_KERNEL);
350 	if (!sinfo->sensors)
351 		return -ENOMEM;
352 
353 	scmi_sensor_description_get(handle, sinfo);
354 
355 	scmi_register_protocol_events(handle,
356 				      SCMI_PROTOCOL_SENSOR, SCMI_PROTO_QUEUE_SZ,
357 				      &sensor_event_ops, sensor_events,
358 				      ARRAY_SIZE(sensor_events),
359 				      sinfo->num_sensors);
360 
361 	sinfo->version = version;
362 	handle->sensor_ops = &sensor_ops;
363 	handle->sensor_priv = sinfo;
364 
365 	return 0;
366 }
367 
368 static int __init scmi_sensors_init(void)
369 {
370 	return scmi_protocol_register(SCMI_PROTOCOL_SENSOR,
371 				      &scmi_sensors_protocol_init);
372 }
373 subsys_initcall(scmi_sensors_init);
374