xref: /linux/drivers/firmware/arm_scmi/power.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * System Control and Management Interface (SCMI) Power Protocol
4  *
5  * Copyright (C) 2018-2022 ARM Ltd.
6  */
7 
8 #define pr_fmt(fmt) "SCMI Notifications POWER - " fmt
9 
10 #include <linux/module.h>
11 #include <linux/scmi_protocol.h>
12 
13 #include "protocols.h"
14 #include "notify.h"
15 
16 /* Updated only after ALL the mandatory features for that version are merged */
17 #define SCMI_PROTOCOL_SUPPORTED_VERSION		0x30001
18 
19 enum scmi_power_protocol_cmd {
20 	POWER_DOMAIN_ATTRIBUTES = 0x3,
21 	POWER_STATE_SET = 0x4,
22 	POWER_STATE_GET = 0x5,
23 	POWER_STATE_NOTIFY = 0x6,
24 	POWER_DOMAIN_NAME_GET = 0x8,
25 };
26 
27 struct scmi_msg_resp_power_attributes {
28 	__le16 num_domains;
29 	__le16 reserved;
30 	__le32 stats_addr_low;
31 	__le32 stats_addr_high;
32 	__le32 stats_size;
33 };
34 
35 struct scmi_msg_resp_power_domain_attributes {
36 	__le32 flags;
37 #define SUPPORTS_STATE_SET_NOTIFY(x)	((x) & BIT(31))
38 #define SUPPORTS_STATE_SET_ASYNC(x)	((x) & BIT(30))
39 #define SUPPORTS_STATE_SET_SYNC(x)	((x) & BIT(29))
40 #define SUPPORTS_EXTENDED_NAMES(x)	((x) & BIT(27))
41 	    u8 name[SCMI_SHORT_NAME_MAX_SIZE];
42 };
43 
44 struct scmi_power_set_state {
45 	__le32 flags;
46 #define STATE_SET_ASYNC		BIT(0)
47 	__le32 domain;
48 	__le32 state;
49 };
50 
51 struct scmi_power_state_notify {
52 	__le32 domain;
53 	__le32 notify_enable;
54 };
55 
56 struct scmi_power_state_notify_payld {
57 	__le32 agent_id;
58 	__le32 domain_id;
59 	__le32 power_state;
60 };
61 
62 struct power_dom_info {
63 	bool state_set_sync;
64 	bool state_set_async;
65 	bool state_set_notify;
66 	char name[SCMI_MAX_STR_SIZE];
67 };
68 
69 struct scmi_power_info {
70 	u32 version;
71 	bool notify_state_change_cmd;
72 	int num_domains;
73 	u64 stats_addr;
74 	u32 stats_size;
75 	struct power_dom_info *dom_info;
76 };
77 
78 static int scmi_power_attributes_get(const struct scmi_protocol_handle *ph,
79 				     struct scmi_power_info *pi)
80 {
81 	int ret;
82 	struct scmi_xfer *t;
83 	struct scmi_msg_resp_power_attributes *attr;
84 
85 	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
86 				      0, sizeof(*attr), &t);
87 	if (ret)
88 		return ret;
89 
90 	attr = t->rx.buf;
91 
92 	ret = ph->xops->do_xfer(ph, t);
93 	if (!ret) {
94 		pi->num_domains = le16_to_cpu(attr->num_domains);
95 		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
96 				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
97 		pi->stats_size = le32_to_cpu(attr->stats_size);
98 	}
99 
100 	ph->xops->xfer_put(ph, t);
101 
102 	if (!ret)
103 		if (!ph->hops->protocol_msg_check(ph, POWER_STATE_NOTIFY, NULL))
104 			pi->notify_state_change_cmd = true;
105 
106 	return ret;
107 }
108 
109 static int
110 scmi_power_domain_attributes_get(const struct scmi_protocol_handle *ph,
111 				 u32 domain, struct power_dom_info *dom_info,
112 				 u32 version, bool notify_state_change_cmd)
113 {
114 	int ret;
115 	u32 flags;
116 	struct scmi_xfer *t;
117 	struct scmi_msg_resp_power_domain_attributes *attr;
118 
119 	ret = ph->xops->xfer_get_init(ph, POWER_DOMAIN_ATTRIBUTES,
120 				      sizeof(domain), sizeof(*attr), &t);
121 	if (ret)
122 		return ret;
123 
124 	put_unaligned_le32(domain, t->tx.buf);
125 	attr = t->rx.buf;
126 
127 	ret = ph->xops->do_xfer(ph, t);
128 	if (!ret) {
129 		flags = le32_to_cpu(attr->flags);
130 
131 		if (notify_state_change_cmd)
132 			dom_info->state_set_notify =
133 				SUPPORTS_STATE_SET_NOTIFY(flags);
134 		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
135 		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
136 		strscpy(dom_info->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE);
137 	}
138 	ph->xops->xfer_put(ph, t);
139 
140 	/*
141 	 * If supported overwrite short name with the extended one;
142 	 * on error just carry on and use already provided short name.
143 	 */
144 	if (!ret && PROTOCOL_REV_MAJOR(version) >= 0x3 &&
145 	    SUPPORTS_EXTENDED_NAMES(flags)) {
146 		ph->hops->extended_name_get(ph, POWER_DOMAIN_NAME_GET,
147 					    domain, NULL, dom_info->name,
148 					    SCMI_MAX_STR_SIZE);
149 	}
150 
151 	return ret;
152 }
153 
154 static int scmi_power_state_set(const struct scmi_protocol_handle *ph,
155 				u32 domain, u32 state)
156 {
157 	int ret;
158 	struct scmi_xfer *t;
159 	struct scmi_power_set_state *st;
160 
161 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_SET, sizeof(*st), 0, &t);
162 	if (ret)
163 		return ret;
164 
165 	st = t->tx.buf;
166 	st->flags = cpu_to_le32(0);
167 	st->domain = cpu_to_le32(domain);
168 	st->state = cpu_to_le32(state);
169 
170 	ret = ph->xops->do_xfer(ph, t);
171 
172 	ph->xops->xfer_put(ph, t);
173 	return ret;
174 }
175 
176 static int scmi_power_state_get(const struct scmi_protocol_handle *ph,
177 				u32 domain, u32 *state)
178 {
179 	int ret;
180 	struct scmi_xfer *t;
181 
182 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_GET, sizeof(u32), sizeof(u32), &t);
183 	if (ret)
184 		return ret;
185 
186 	put_unaligned_le32(domain, t->tx.buf);
187 
188 	ret = ph->xops->do_xfer(ph, t);
189 	if (!ret)
190 		*state = get_unaligned_le32(t->rx.buf);
191 
192 	ph->xops->xfer_put(ph, t);
193 	return ret;
194 }
195 
196 static int scmi_power_num_domains_get(const struct scmi_protocol_handle *ph)
197 {
198 	struct scmi_power_info *pi = ph->get_priv(ph);
199 
200 	return pi->num_domains;
201 }
202 
203 static const char *
204 scmi_power_name_get(const struct scmi_protocol_handle *ph,
205 		    u32 domain)
206 {
207 	struct scmi_power_info *pi = ph->get_priv(ph);
208 	struct power_dom_info *dom = pi->dom_info + domain;
209 
210 	return dom->name;
211 }
212 
213 static const struct scmi_power_proto_ops power_proto_ops = {
214 	.num_domains_get = scmi_power_num_domains_get,
215 	.name_get = scmi_power_name_get,
216 	.state_set = scmi_power_state_set,
217 	.state_get = scmi_power_state_get,
218 };
219 
220 static int scmi_power_request_notify(const struct scmi_protocol_handle *ph,
221 				     u32 domain, bool enable)
222 {
223 	int ret;
224 	struct scmi_xfer *t;
225 	struct scmi_power_state_notify *notify;
226 
227 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_NOTIFY,
228 				      sizeof(*notify), 0, &t);
229 	if (ret)
230 		return ret;
231 
232 	notify = t->tx.buf;
233 	notify->domain = cpu_to_le32(domain);
234 	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
235 
236 	ret = ph->xops->do_xfer(ph, t);
237 
238 	ph->xops->xfer_put(ph, t);
239 	return ret;
240 }
241 
242 static bool scmi_power_notify_supported(const struct scmi_protocol_handle *ph,
243 					u8 evt_id, u32 src_id)
244 {
245 	struct power_dom_info *dom;
246 	struct scmi_power_info *pinfo = ph->get_priv(ph);
247 
248 	if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED ||
249 	    src_id >= pinfo->num_domains)
250 		return false;
251 
252 	dom = pinfo->dom_info + src_id;
253 	return dom->state_set_notify;
254 }
255 
256 static int scmi_power_set_notify_enabled(const struct scmi_protocol_handle *ph,
257 					 u8 evt_id, u32 src_id, bool enable)
258 {
259 	int ret;
260 
261 	ret = scmi_power_request_notify(ph, src_id, enable);
262 	if (ret)
263 		pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n",
264 			 evt_id, src_id, ret);
265 
266 	return ret;
267 }
268 
269 static void *
270 scmi_power_fill_custom_report(const struct scmi_protocol_handle *ph,
271 			      u8 evt_id, ktime_t timestamp,
272 			      const void *payld, size_t payld_sz,
273 			      void *report, u32 *src_id)
274 {
275 	const struct scmi_power_state_notify_payld *p = payld;
276 	struct scmi_power_state_changed_report *r = report;
277 
278 	if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || sizeof(*p) != payld_sz)
279 		return NULL;
280 
281 	r->timestamp = timestamp;
282 	r->agent_id = le32_to_cpu(p->agent_id);
283 	r->domain_id = le32_to_cpu(p->domain_id);
284 	r->power_state = le32_to_cpu(p->power_state);
285 	*src_id = r->domain_id;
286 
287 	return r;
288 }
289 
290 static int scmi_power_get_num_sources(const struct scmi_protocol_handle *ph)
291 {
292 	struct scmi_power_info *pinfo = ph->get_priv(ph);
293 
294 	if (!pinfo)
295 		return -EINVAL;
296 
297 	return pinfo->num_domains;
298 }
299 
300 static const struct scmi_event power_events[] = {
301 	{
302 		.id = SCMI_EVENT_POWER_STATE_CHANGED,
303 		.max_payld_sz = sizeof(struct scmi_power_state_notify_payld),
304 		.max_report_sz =
305 			sizeof(struct scmi_power_state_changed_report),
306 	},
307 };
308 
309 static const struct scmi_event_ops power_event_ops = {
310 	.is_notify_supported = scmi_power_notify_supported,
311 	.get_num_sources = scmi_power_get_num_sources,
312 	.set_notify_enabled = scmi_power_set_notify_enabled,
313 	.fill_custom_report = scmi_power_fill_custom_report,
314 };
315 
316 static const struct scmi_protocol_events power_protocol_events = {
317 	.queue_sz = SCMI_PROTO_QUEUE_SZ,
318 	.ops = &power_event_ops,
319 	.evts = power_events,
320 	.num_events = ARRAY_SIZE(power_events),
321 };
322 
323 static int scmi_power_protocol_init(const struct scmi_protocol_handle *ph)
324 {
325 	int domain, ret;
326 	u32 version;
327 	struct scmi_power_info *pinfo;
328 
329 	ret = ph->xops->version_get(ph, &version);
330 	if (ret)
331 		return ret;
332 
333 	dev_dbg(ph->dev, "Power Version %d.%d\n",
334 		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
335 
336 	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
337 	if (!pinfo)
338 		return -ENOMEM;
339 
340 	ret = scmi_power_attributes_get(ph, pinfo);
341 	if (ret)
342 		return ret;
343 
344 	pinfo->dom_info = devm_kcalloc(ph->dev, pinfo->num_domains,
345 				       sizeof(*pinfo->dom_info), GFP_KERNEL);
346 	if (!pinfo->dom_info)
347 		return -ENOMEM;
348 
349 	for (domain = 0; domain < pinfo->num_domains; domain++) {
350 		struct power_dom_info *dom = pinfo->dom_info + domain;
351 
352 		scmi_power_domain_attributes_get(ph, domain, dom, version,
353 						 pinfo->notify_state_change_cmd);
354 	}
355 
356 	pinfo->version = version;
357 
358 	return ph->set_priv(ph, pinfo, version);
359 }
360 
361 static const struct scmi_protocol scmi_power = {
362 	.id = SCMI_PROTOCOL_POWER,
363 	.owner = THIS_MODULE,
364 	.instance_init = &scmi_power_protocol_init,
365 	.ops = &power_proto_ops,
366 	.events = &power_protocol_events,
367 	.supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
368 };
369 
370 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(power, scmi_power)
371