xref: /linux/drivers/firmware/arm_scmi/power.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
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		0x30000
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 	int num_domains;
72 	u64 stats_addr;
73 	u32 stats_size;
74 	struct power_dom_info *dom_info;
75 };
76 
77 static int scmi_power_attributes_get(const struct scmi_protocol_handle *ph,
78 				     struct scmi_power_info *pi)
79 {
80 	int ret;
81 	struct scmi_xfer *t;
82 	struct scmi_msg_resp_power_attributes *attr;
83 
84 	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
85 				      0, sizeof(*attr), &t);
86 	if (ret)
87 		return ret;
88 
89 	attr = t->rx.buf;
90 
91 	ret = ph->xops->do_xfer(ph, t);
92 	if (!ret) {
93 		pi->num_domains = le16_to_cpu(attr->num_domains);
94 		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
95 				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
96 		pi->stats_size = le32_to_cpu(attr->stats_size);
97 	}
98 
99 	ph->xops->xfer_put(ph, t);
100 	return ret;
101 }
102 
103 static int
104 scmi_power_domain_attributes_get(const struct scmi_protocol_handle *ph,
105 				 u32 domain, struct power_dom_info *dom_info,
106 				 u32 version)
107 {
108 	int ret;
109 	u32 flags;
110 	struct scmi_xfer *t;
111 	struct scmi_msg_resp_power_domain_attributes *attr;
112 
113 	ret = ph->xops->xfer_get_init(ph, POWER_DOMAIN_ATTRIBUTES,
114 				      sizeof(domain), sizeof(*attr), &t);
115 	if (ret)
116 		return ret;
117 
118 	put_unaligned_le32(domain, t->tx.buf);
119 	attr = t->rx.buf;
120 
121 	ret = ph->xops->do_xfer(ph, t);
122 	if (!ret) {
123 		flags = le32_to_cpu(attr->flags);
124 
125 		dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
126 		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
127 		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
128 		strscpy(dom_info->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE);
129 	}
130 	ph->xops->xfer_put(ph, t);
131 
132 	/*
133 	 * If supported overwrite short name with the extended one;
134 	 * on error just carry on and use already provided short name.
135 	 */
136 	if (!ret && PROTOCOL_REV_MAJOR(version) >= 0x3 &&
137 	    SUPPORTS_EXTENDED_NAMES(flags)) {
138 		ph->hops->extended_name_get(ph, POWER_DOMAIN_NAME_GET,
139 					    domain, NULL, dom_info->name,
140 					    SCMI_MAX_STR_SIZE);
141 	}
142 
143 	return ret;
144 }
145 
146 static int scmi_power_state_set(const struct scmi_protocol_handle *ph,
147 				u32 domain, u32 state)
148 {
149 	int ret;
150 	struct scmi_xfer *t;
151 	struct scmi_power_set_state *st;
152 
153 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_SET, sizeof(*st), 0, &t);
154 	if (ret)
155 		return ret;
156 
157 	st = t->tx.buf;
158 	st->flags = cpu_to_le32(0);
159 	st->domain = cpu_to_le32(domain);
160 	st->state = cpu_to_le32(state);
161 
162 	ret = ph->xops->do_xfer(ph, t);
163 
164 	ph->xops->xfer_put(ph, t);
165 	return ret;
166 }
167 
168 static int scmi_power_state_get(const struct scmi_protocol_handle *ph,
169 				u32 domain, u32 *state)
170 {
171 	int ret;
172 	struct scmi_xfer *t;
173 
174 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_GET, sizeof(u32), sizeof(u32), &t);
175 	if (ret)
176 		return ret;
177 
178 	put_unaligned_le32(domain, t->tx.buf);
179 
180 	ret = ph->xops->do_xfer(ph, t);
181 	if (!ret)
182 		*state = get_unaligned_le32(t->rx.buf);
183 
184 	ph->xops->xfer_put(ph, t);
185 	return ret;
186 }
187 
188 static int scmi_power_num_domains_get(const struct scmi_protocol_handle *ph)
189 {
190 	struct scmi_power_info *pi = ph->get_priv(ph);
191 
192 	return pi->num_domains;
193 }
194 
195 static const char *
196 scmi_power_name_get(const struct scmi_protocol_handle *ph,
197 		    u32 domain)
198 {
199 	struct scmi_power_info *pi = ph->get_priv(ph);
200 	struct power_dom_info *dom = pi->dom_info + domain;
201 
202 	return dom->name;
203 }
204 
205 static const struct scmi_power_proto_ops power_proto_ops = {
206 	.num_domains_get = scmi_power_num_domains_get,
207 	.name_get = scmi_power_name_get,
208 	.state_set = scmi_power_state_set,
209 	.state_get = scmi_power_state_get,
210 };
211 
212 static int scmi_power_request_notify(const struct scmi_protocol_handle *ph,
213 				     u32 domain, bool enable)
214 {
215 	int ret;
216 	struct scmi_xfer *t;
217 	struct scmi_power_state_notify *notify;
218 
219 	ret = ph->xops->xfer_get_init(ph, POWER_STATE_NOTIFY,
220 				      sizeof(*notify), 0, &t);
221 	if (ret)
222 		return ret;
223 
224 	notify = t->tx.buf;
225 	notify->domain = cpu_to_le32(domain);
226 	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
227 
228 	ret = ph->xops->do_xfer(ph, t);
229 
230 	ph->xops->xfer_put(ph, t);
231 	return ret;
232 }
233 
234 static int scmi_power_set_notify_enabled(const struct scmi_protocol_handle *ph,
235 					 u8 evt_id, u32 src_id, bool enable)
236 {
237 	int ret;
238 
239 	ret = scmi_power_request_notify(ph, src_id, enable);
240 	if (ret)
241 		pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n",
242 			 evt_id, src_id, ret);
243 
244 	return ret;
245 }
246 
247 static void *
248 scmi_power_fill_custom_report(const struct scmi_protocol_handle *ph,
249 			      u8 evt_id, ktime_t timestamp,
250 			      const void *payld, size_t payld_sz,
251 			      void *report, u32 *src_id)
252 {
253 	const struct scmi_power_state_notify_payld *p = payld;
254 	struct scmi_power_state_changed_report *r = report;
255 
256 	if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || sizeof(*p) != payld_sz)
257 		return NULL;
258 
259 	r->timestamp = timestamp;
260 	r->agent_id = le32_to_cpu(p->agent_id);
261 	r->domain_id = le32_to_cpu(p->domain_id);
262 	r->power_state = le32_to_cpu(p->power_state);
263 	*src_id = r->domain_id;
264 
265 	return r;
266 }
267 
268 static int scmi_power_get_num_sources(const struct scmi_protocol_handle *ph)
269 {
270 	struct scmi_power_info *pinfo = ph->get_priv(ph);
271 
272 	if (!pinfo)
273 		return -EINVAL;
274 
275 	return pinfo->num_domains;
276 }
277 
278 static const struct scmi_event power_events[] = {
279 	{
280 		.id = SCMI_EVENT_POWER_STATE_CHANGED,
281 		.max_payld_sz = sizeof(struct scmi_power_state_notify_payld),
282 		.max_report_sz =
283 			sizeof(struct scmi_power_state_changed_report),
284 	},
285 };
286 
287 static const struct scmi_event_ops power_event_ops = {
288 	.get_num_sources = scmi_power_get_num_sources,
289 	.set_notify_enabled = scmi_power_set_notify_enabled,
290 	.fill_custom_report = scmi_power_fill_custom_report,
291 };
292 
293 static const struct scmi_protocol_events power_protocol_events = {
294 	.queue_sz = SCMI_PROTO_QUEUE_SZ,
295 	.ops = &power_event_ops,
296 	.evts = power_events,
297 	.num_events = ARRAY_SIZE(power_events),
298 };
299 
300 static int scmi_power_protocol_init(const struct scmi_protocol_handle *ph)
301 {
302 	int domain, ret;
303 	u32 version;
304 	struct scmi_power_info *pinfo;
305 
306 	ret = ph->xops->version_get(ph, &version);
307 	if (ret)
308 		return ret;
309 
310 	dev_dbg(ph->dev, "Power Version %d.%d\n",
311 		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
312 
313 	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
314 	if (!pinfo)
315 		return -ENOMEM;
316 
317 	ret = scmi_power_attributes_get(ph, pinfo);
318 	if (ret)
319 		return ret;
320 
321 	pinfo->dom_info = devm_kcalloc(ph->dev, pinfo->num_domains,
322 				       sizeof(*pinfo->dom_info), GFP_KERNEL);
323 	if (!pinfo->dom_info)
324 		return -ENOMEM;
325 
326 	for (domain = 0; domain < pinfo->num_domains; domain++) {
327 		struct power_dom_info *dom = pinfo->dom_info + domain;
328 
329 		scmi_power_domain_attributes_get(ph, domain, dom, version);
330 	}
331 
332 	pinfo->version = version;
333 
334 	return ph->set_priv(ph, pinfo, version);
335 }
336 
337 static const struct scmi_protocol scmi_power = {
338 	.id = SCMI_PROTOCOL_POWER,
339 	.owner = THIS_MODULE,
340 	.instance_init = &scmi_power_protocol_init,
341 	.ops = &power_proto_ops,
342 	.events = &power_protocol_events,
343 	.supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
344 };
345 
346 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(power, scmi_power)
347