1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * System Control and Management Interface (SCMI) Power Protocol
4  *
5  * Copyright (C) 2018 ARM Ltd.
6  */
7 
8 #define pr_fmt(fmt) "SCMI Notifications POWER - " fmt
9 
10 #include <linux/scmi_protocol.h>
11 
12 #include "common.h"
13 #include "notify.h"
14 
15 enum scmi_power_protocol_cmd {
16 	POWER_DOMAIN_ATTRIBUTES = 0x3,
17 	POWER_STATE_SET = 0x4,
18 	POWER_STATE_GET = 0x5,
19 	POWER_STATE_NOTIFY = 0x6,
20 };
21 
22 struct scmi_msg_resp_power_attributes {
23 	__le16 num_domains;
24 	__le16 reserved;
25 	__le32 stats_addr_low;
26 	__le32 stats_addr_high;
27 	__le32 stats_size;
28 };
29 
30 struct scmi_msg_resp_power_domain_attributes {
31 	__le32 flags;
32 #define SUPPORTS_STATE_SET_NOTIFY(x)	((x) & BIT(31))
33 #define SUPPORTS_STATE_SET_ASYNC(x)	((x) & BIT(30))
34 #define SUPPORTS_STATE_SET_SYNC(x)	((x) & BIT(29))
35 	    u8 name[SCMI_MAX_STR_SIZE];
36 };
37 
38 struct scmi_power_set_state {
39 	__le32 flags;
40 #define STATE_SET_ASYNC		BIT(0)
41 	__le32 domain;
42 	__le32 state;
43 };
44 
45 struct scmi_power_state_notify {
46 	__le32 domain;
47 	__le32 notify_enable;
48 };
49 
50 struct scmi_power_state_notify_payld {
51 	__le32 agent_id;
52 	__le32 domain_id;
53 	__le32 power_state;
54 };
55 
56 struct power_dom_info {
57 	bool state_set_sync;
58 	bool state_set_async;
59 	bool state_set_notify;
60 	char name[SCMI_MAX_STR_SIZE];
61 };
62 
63 struct scmi_power_info {
64 	u32 version;
65 	int num_domains;
66 	u64 stats_addr;
67 	u32 stats_size;
68 	struct power_dom_info *dom_info;
69 };
70 
71 static int scmi_power_attributes_get(const struct scmi_handle *handle,
72 				     struct scmi_power_info *pi)
73 {
74 	int ret;
75 	struct scmi_xfer *t;
76 	struct scmi_msg_resp_power_attributes *attr;
77 
78 	ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
79 				 SCMI_PROTOCOL_POWER, 0, sizeof(*attr), &t);
80 	if (ret)
81 		return ret;
82 
83 	attr = t->rx.buf;
84 
85 	ret = scmi_do_xfer(handle, t);
86 	if (!ret) {
87 		pi->num_domains = le16_to_cpu(attr->num_domains);
88 		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
89 				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
90 		pi->stats_size = le32_to_cpu(attr->stats_size);
91 	}
92 
93 	scmi_xfer_put(handle, t);
94 	return ret;
95 }
96 
97 static int
98 scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
99 				 struct power_dom_info *dom_info)
100 {
101 	int ret;
102 	struct scmi_xfer *t;
103 	struct scmi_msg_resp_power_domain_attributes *attr;
104 
105 	ret = scmi_xfer_get_init(handle, POWER_DOMAIN_ATTRIBUTES,
106 				 SCMI_PROTOCOL_POWER, sizeof(domain),
107 				 sizeof(*attr), &t);
108 	if (ret)
109 		return ret;
110 
111 	put_unaligned_le32(domain, t->tx.buf);
112 	attr = t->rx.buf;
113 
114 	ret = scmi_do_xfer(handle, t);
115 	if (!ret) {
116 		u32 flags = le32_to_cpu(attr->flags);
117 
118 		dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
119 		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
120 		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
121 		strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
122 	}
123 
124 	scmi_xfer_put(handle, t);
125 	return ret;
126 }
127 
128 static int
129 scmi_power_state_set(const struct scmi_handle *handle, u32 domain, u32 state)
130 {
131 	int ret;
132 	struct scmi_xfer *t;
133 	struct scmi_power_set_state *st;
134 
135 	ret = scmi_xfer_get_init(handle, POWER_STATE_SET, SCMI_PROTOCOL_POWER,
136 				 sizeof(*st), 0, &t);
137 	if (ret)
138 		return ret;
139 
140 	st = t->tx.buf;
141 	st->flags = cpu_to_le32(0);
142 	st->domain = cpu_to_le32(domain);
143 	st->state = cpu_to_le32(state);
144 
145 	ret = scmi_do_xfer(handle, t);
146 
147 	scmi_xfer_put(handle, t);
148 	return ret;
149 }
150 
151 static int
152 scmi_power_state_get(const struct scmi_handle *handle, u32 domain, u32 *state)
153 {
154 	int ret;
155 	struct scmi_xfer *t;
156 
157 	ret = scmi_xfer_get_init(handle, POWER_STATE_GET, SCMI_PROTOCOL_POWER,
158 				 sizeof(u32), sizeof(u32), &t);
159 	if (ret)
160 		return ret;
161 
162 	put_unaligned_le32(domain, t->tx.buf);
163 
164 	ret = scmi_do_xfer(handle, t);
165 	if (!ret)
166 		*state = get_unaligned_le32(t->rx.buf);
167 
168 	scmi_xfer_put(handle, t);
169 	return ret;
170 }
171 
172 static int scmi_power_num_domains_get(const struct scmi_handle *handle)
173 {
174 	struct scmi_power_info *pi = handle->power_priv;
175 
176 	return pi->num_domains;
177 }
178 
179 static char *scmi_power_name_get(const struct scmi_handle *handle, u32 domain)
180 {
181 	struct scmi_power_info *pi = handle->power_priv;
182 	struct power_dom_info *dom = pi->dom_info + domain;
183 
184 	return dom->name;
185 }
186 
187 static struct scmi_power_ops power_ops = {
188 	.num_domains_get = scmi_power_num_domains_get,
189 	.name_get = scmi_power_name_get,
190 	.state_set = scmi_power_state_set,
191 	.state_get = scmi_power_state_get,
192 };
193 
194 static int scmi_power_request_notify(const struct scmi_handle *handle,
195 				     u32 domain, bool enable)
196 {
197 	int ret;
198 	struct scmi_xfer *t;
199 	struct scmi_power_state_notify *notify;
200 
201 	ret = scmi_xfer_get_init(handle, POWER_STATE_NOTIFY,
202 				 SCMI_PROTOCOL_POWER, sizeof(*notify), 0, &t);
203 	if (ret)
204 		return ret;
205 
206 	notify = t->tx.buf;
207 	notify->domain = cpu_to_le32(domain);
208 	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
209 
210 	ret = scmi_do_xfer(handle, t);
211 
212 	scmi_xfer_put(handle, t);
213 	return ret;
214 }
215 
216 static int scmi_power_set_notify_enabled(const struct scmi_handle *handle,
217 					 u8 evt_id, u32 src_id, bool enable)
218 {
219 	int ret;
220 
221 	ret = scmi_power_request_notify(handle, src_id, enable);
222 	if (ret)
223 		pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n",
224 			 evt_id, src_id, ret);
225 
226 	return ret;
227 }
228 
229 static void *scmi_power_fill_custom_report(const struct scmi_handle *handle,
230 					   u8 evt_id, ktime_t timestamp,
231 					   const void *payld, size_t payld_sz,
232 					   void *report, u32 *src_id)
233 {
234 	const struct scmi_power_state_notify_payld *p = payld;
235 	struct scmi_power_state_changed_report *r = report;
236 
237 	if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || sizeof(*p) != payld_sz)
238 		return NULL;
239 
240 	r->timestamp = timestamp;
241 	r->agent_id = le32_to_cpu(p->agent_id);
242 	r->domain_id = le32_to_cpu(p->domain_id);
243 	r->power_state = le32_to_cpu(p->power_state);
244 	*src_id = r->domain_id;
245 
246 	return r;
247 }
248 
249 static const struct scmi_event power_events[] = {
250 	{
251 		.id = SCMI_EVENT_POWER_STATE_CHANGED,
252 		.max_payld_sz = sizeof(struct scmi_power_state_notify_payld),
253 		.max_report_sz =
254 			sizeof(struct scmi_power_state_changed_report),
255 	},
256 };
257 
258 static const struct scmi_event_ops power_event_ops = {
259 	.set_notify_enabled = scmi_power_set_notify_enabled,
260 	.fill_custom_report = scmi_power_fill_custom_report,
261 };
262 
263 static int scmi_power_protocol_init(struct scmi_handle *handle)
264 {
265 	int domain;
266 	u32 version;
267 	struct scmi_power_info *pinfo;
268 
269 	scmi_version_get(handle, SCMI_PROTOCOL_POWER, &version);
270 
271 	dev_dbg(handle->dev, "Power Version %d.%d\n",
272 		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
273 
274 	pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
275 	if (!pinfo)
276 		return -ENOMEM;
277 
278 	scmi_power_attributes_get(handle, pinfo);
279 
280 	pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
281 				       sizeof(*pinfo->dom_info), GFP_KERNEL);
282 	if (!pinfo->dom_info)
283 		return -ENOMEM;
284 
285 	for (domain = 0; domain < pinfo->num_domains; domain++) {
286 		struct power_dom_info *dom = pinfo->dom_info + domain;
287 
288 		scmi_power_domain_attributes_get(handle, domain, dom);
289 	}
290 
291 	scmi_register_protocol_events(handle,
292 				      SCMI_PROTOCOL_POWER, SCMI_PROTO_QUEUE_SZ,
293 				      &power_event_ops, power_events,
294 				      ARRAY_SIZE(power_events),
295 				      pinfo->num_domains);
296 
297 	pinfo->version = version;
298 	handle->power_ops = &power_ops;
299 	handle->power_priv = pinfo;
300 
301 	return 0;
302 }
303 
304 static int __init scmi_power_init(void)
305 {
306 	return scmi_protocol_register(SCMI_PROTOCOL_POWER,
307 				      &scmi_power_protocol_init);
308 }
309 subsys_initcall(scmi_power_init);
310