xref: /linux/drivers/firmware/arm_scmi/base.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * System Control and Management Interface (SCMI) Base Protocol
4  *
5  * Copyright (C) 2018 ARM Ltd.
6  */
7 
8 #define pr_fmt(fmt) "SCMI Notifications BASE - " fmt
9 
10 #include <linux/scmi_protocol.h>
11 
12 #include "common.h"
13 #include "notify.h"
14 
15 #define SCMI_BASE_NUM_SOURCES		1
16 #define SCMI_BASE_MAX_CMD_ERR_COUNT	1024
17 
18 enum scmi_base_protocol_cmd {
19 	BASE_DISCOVER_VENDOR = 0x3,
20 	BASE_DISCOVER_SUB_VENDOR = 0x4,
21 	BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
22 	BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
23 	BASE_DISCOVER_AGENT = 0x7,
24 	BASE_NOTIFY_ERRORS = 0x8,
25 	BASE_SET_DEVICE_PERMISSIONS = 0x9,
26 	BASE_SET_PROTOCOL_PERMISSIONS = 0xa,
27 	BASE_RESET_AGENT_CONFIGURATION = 0xb,
28 };
29 
30 struct scmi_msg_resp_base_attributes {
31 	u8 num_protocols;
32 	u8 num_agents;
33 	__le16 reserved;
34 };
35 
36 struct scmi_msg_base_error_notify {
37 	__le32 event_control;
38 #define BASE_TP_NOTIFY_ALL	BIT(0)
39 };
40 
41 struct scmi_base_error_notify_payld {
42 	__le32 agent_id;
43 	__le32 error_status;
44 #define IS_FATAL_ERROR(x)	((x) & BIT(31))
45 #define ERROR_CMD_COUNT(x)	FIELD_GET(GENMASK(9, 0), (x))
46 	__le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT];
47 };
48 
49 /**
50  * scmi_base_attributes_get() - gets the implementation details
51  *	that are associated with the base protocol.
52  *
53  * @handle: SCMI entity handle
54  *
55  * Return: 0 on success, else appropriate SCMI error.
56  */
57 static int scmi_base_attributes_get(const struct scmi_handle *handle)
58 {
59 	int ret;
60 	struct scmi_xfer *t;
61 	struct scmi_msg_resp_base_attributes *attr_info;
62 	struct scmi_revision_info *rev = handle->version;
63 
64 	ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
65 				 SCMI_PROTOCOL_BASE, 0, sizeof(*attr_info), &t);
66 	if (ret)
67 		return ret;
68 
69 	ret = scmi_do_xfer(handle, t);
70 	if (!ret) {
71 		attr_info = t->rx.buf;
72 		rev->num_protocols = attr_info->num_protocols;
73 		rev->num_agents = attr_info->num_agents;
74 	}
75 
76 	scmi_xfer_put(handle, t);
77 
78 	return ret;
79 }
80 
81 /**
82  * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
83  *
84  * @handle: SCMI entity handle
85  * @sub_vendor: specify true if sub-vendor ID is needed
86  *
87  * Return: 0 on success, else appropriate SCMI error.
88  */
89 static int
90 scmi_base_vendor_id_get(const struct scmi_handle *handle, bool sub_vendor)
91 {
92 	u8 cmd;
93 	int ret, size;
94 	char *vendor_id;
95 	struct scmi_xfer *t;
96 	struct scmi_revision_info *rev = handle->version;
97 
98 	if (sub_vendor) {
99 		cmd = BASE_DISCOVER_SUB_VENDOR;
100 		vendor_id = rev->sub_vendor_id;
101 		size = ARRAY_SIZE(rev->sub_vendor_id);
102 	} else {
103 		cmd = BASE_DISCOVER_VENDOR;
104 		vendor_id = rev->vendor_id;
105 		size = ARRAY_SIZE(rev->vendor_id);
106 	}
107 
108 	ret = scmi_xfer_get_init(handle, cmd, SCMI_PROTOCOL_BASE, 0, size, &t);
109 	if (ret)
110 		return ret;
111 
112 	ret = scmi_do_xfer(handle, t);
113 	if (!ret)
114 		memcpy(vendor_id, t->rx.buf, size);
115 
116 	scmi_xfer_put(handle, t);
117 
118 	return ret;
119 }
120 
121 /**
122  * scmi_base_implementation_version_get() - gets a vendor-specific
123  *	implementation 32-bit version. The format of the version number is
124  *	vendor-specific
125  *
126  * @handle: SCMI entity handle
127  *
128  * Return: 0 on success, else appropriate SCMI error.
129  */
130 static int
131 scmi_base_implementation_version_get(const struct scmi_handle *handle)
132 {
133 	int ret;
134 	__le32 *impl_ver;
135 	struct scmi_xfer *t;
136 	struct scmi_revision_info *rev = handle->version;
137 
138 	ret = scmi_xfer_get_init(handle, BASE_DISCOVER_IMPLEMENT_VERSION,
139 				 SCMI_PROTOCOL_BASE, 0, sizeof(*impl_ver), &t);
140 	if (ret)
141 		return ret;
142 
143 	ret = scmi_do_xfer(handle, t);
144 	if (!ret) {
145 		impl_ver = t->rx.buf;
146 		rev->impl_ver = le32_to_cpu(*impl_ver);
147 	}
148 
149 	scmi_xfer_put(handle, t);
150 
151 	return ret;
152 }
153 
154 /**
155  * scmi_base_implementation_list_get() - gets the list of protocols it is
156  *	OSPM is allowed to access
157  *
158  * @handle: SCMI entity handle
159  * @protocols_imp: pointer to hold the list of protocol identifiers
160  *
161  * Return: 0 on success, else appropriate SCMI error.
162  */
163 static int scmi_base_implementation_list_get(const struct scmi_handle *handle,
164 					     u8 *protocols_imp)
165 {
166 	u8 *list;
167 	int ret, loop;
168 	struct scmi_xfer *t;
169 	__le32 *num_skip, *num_ret;
170 	u32 tot_num_ret = 0, loop_num_ret;
171 	struct device *dev = handle->dev;
172 
173 	ret = scmi_xfer_get_init(handle, BASE_DISCOVER_LIST_PROTOCOLS,
174 				 SCMI_PROTOCOL_BASE, sizeof(*num_skip), 0, &t);
175 	if (ret)
176 		return ret;
177 
178 	num_skip = t->tx.buf;
179 	num_ret = t->rx.buf;
180 	list = t->rx.buf + sizeof(*num_ret);
181 
182 	do {
183 		/* Set the number of protocols to be skipped/already read */
184 		*num_skip = cpu_to_le32(tot_num_ret);
185 
186 		ret = scmi_do_xfer(handle, t);
187 		if (ret)
188 			break;
189 
190 		loop_num_ret = le32_to_cpu(*num_ret);
191 		if (tot_num_ret + loop_num_ret > MAX_PROTOCOLS_IMP) {
192 			dev_err(dev, "No. of Protocol > MAX_PROTOCOLS_IMP");
193 			break;
194 		}
195 
196 		for (loop = 0; loop < loop_num_ret; loop++)
197 			protocols_imp[tot_num_ret + loop] = *(list + loop);
198 
199 		tot_num_ret += loop_num_ret;
200 
201 		scmi_reset_rx_to_maxsz(handle, t);
202 	} while (loop_num_ret);
203 
204 	scmi_xfer_put(handle, t);
205 
206 	return ret;
207 }
208 
209 /**
210  * scmi_base_discover_agent_get() - discover the name of an agent
211  *
212  * @handle: SCMI entity handle
213  * @id: Agent identifier
214  * @name: Agent identifier ASCII string
215  *
216  * An agent id of 0 is reserved to identify the platform itself.
217  * Generally operating system is represented as "OSPM"
218  *
219  * Return: 0 on success, else appropriate SCMI error.
220  */
221 static int scmi_base_discover_agent_get(const struct scmi_handle *handle,
222 					int id, char *name)
223 {
224 	int ret;
225 	struct scmi_xfer *t;
226 
227 	ret = scmi_xfer_get_init(handle, BASE_DISCOVER_AGENT,
228 				 SCMI_PROTOCOL_BASE, sizeof(__le32),
229 				 SCMI_MAX_STR_SIZE, &t);
230 	if (ret)
231 		return ret;
232 
233 	put_unaligned_le32(id, t->tx.buf);
234 
235 	ret = scmi_do_xfer(handle, t);
236 	if (!ret)
237 		strlcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE);
238 
239 	scmi_xfer_put(handle, t);
240 
241 	return ret;
242 }
243 
244 static int scmi_base_error_notify(const struct scmi_handle *handle, bool enable)
245 {
246 	int ret;
247 	u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0;
248 	struct scmi_xfer *t;
249 	struct scmi_msg_base_error_notify *cfg;
250 
251 	ret = scmi_xfer_get_init(handle, BASE_NOTIFY_ERRORS,
252 				 SCMI_PROTOCOL_BASE, sizeof(*cfg), 0, &t);
253 	if (ret)
254 		return ret;
255 
256 	cfg = t->tx.buf;
257 	cfg->event_control = cpu_to_le32(evt_cntl);
258 
259 	ret = scmi_do_xfer(handle, t);
260 
261 	scmi_xfer_put(handle, t);
262 	return ret;
263 }
264 
265 static int scmi_base_set_notify_enabled(const struct scmi_handle *handle,
266 					u8 evt_id, u32 src_id, bool enable)
267 {
268 	int ret;
269 
270 	ret = scmi_base_error_notify(handle, enable);
271 	if (ret)
272 		pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret);
273 
274 	return ret;
275 }
276 
277 static void *scmi_base_fill_custom_report(const struct scmi_handle *handle,
278 					  u8 evt_id, ktime_t timestamp,
279 					  const void *payld, size_t payld_sz,
280 					  void *report, u32 *src_id)
281 {
282 	int i;
283 	const struct scmi_base_error_notify_payld *p = payld;
284 	struct scmi_base_error_report *r = report;
285 
286 	/*
287 	 * BaseError notification payload is variable in size but
288 	 * up to a maximum length determined by the struct ponted by p.
289 	 * Instead payld_sz is the effective length of this notification
290 	 * payload so cannot be greater of the maximum allowed size as
291 	 * pointed by p.
292 	 */
293 	if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz)
294 		return NULL;
295 
296 	r->timestamp = timestamp;
297 	r->agent_id = le32_to_cpu(p->agent_id);
298 	r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status));
299 	r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status));
300 	for (i = 0; i < r->cmd_count; i++)
301 		r->reports[i] = le64_to_cpu(p->msg_reports[i]);
302 	*src_id = 0;
303 
304 	return r;
305 }
306 
307 static const struct scmi_event base_events[] = {
308 	{
309 		.id = SCMI_EVENT_BASE_ERROR_EVENT,
310 		.max_payld_sz = sizeof(struct scmi_base_error_notify_payld),
311 		.max_report_sz = sizeof(struct scmi_base_error_report) +
312 				  SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64),
313 	},
314 };
315 
316 static const struct scmi_event_ops base_event_ops = {
317 	.set_notify_enabled = scmi_base_set_notify_enabled,
318 	.fill_custom_report = scmi_base_fill_custom_report,
319 };
320 
321 int scmi_base_protocol_init(struct scmi_handle *h)
322 {
323 	int id, ret;
324 	u8 *prot_imp;
325 	u32 version;
326 	char name[SCMI_MAX_STR_SIZE];
327 	const struct scmi_handle *handle = h;
328 	struct device *dev = handle->dev;
329 	struct scmi_revision_info *rev = handle->version;
330 
331 	ret = scmi_version_get(handle, SCMI_PROTOCOL_BASE, &version);
332 	if (ret)
333 		return ret;
334 
335 	prot_imp = devm_kcalloc(dev, MAX_PROTOCOLS_IMP, sizeof(u8), GFP_KERNEL);
336 	if (!prot_imp)
337 		return -ENOMEM;
338 
339 	rev->major_ver = PROTOCOL_REV_MAJOR(version),
340 	rev->minor_ver = PROTOCOL_REV_MINOR(version);
341 
342 	scmi_base_attributes_get(handle);
343 	scmi_base_vendor_id_get(handle, false);
344 	scmi_base_vendor_id_get(handle, true);
345 	scmi_base_implementation_version_get(handle);
346 	scmi_base_implementation_list_get(handle, prot_imp);
347 	scmi_setup_protocol_implemented(handle, prot_imp);
348 
349 	dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
350 		 rev->major_ver, rev->minor_ver, rev->vendor_id,
351 		 rev->sub_vendor_id, rev->impl_ver);
352 	dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
353 		rev->num_agents);
354 
355 	scmi_register_protocol_events(handle, SCMI_PROTOCOL_BASE,
356 				      (4 * SCMI_PROTO_QUEUE_SZ),
357 				      &base_event_ops, base_events,
358 				      ARRAY_SIZE(base_events),
359 				      SCMI_BASE_NUM_SOURCES);
360 
361 	for (id = 0; id < rev->num_agents; id++) {
362 		scmi_base_discover_agent_get(handle, id, name);
363 		dev_dbg(dev, "Agent %d: %s\n", id, name);
364 	}
365 
366 	return 0;
367 }
368