1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * System Control and Management Interface (SCMI) Base Protocol
4 *
5 * Copyright (C) 2018-2021 ARM Ltd.
6 */
7
8 #define pr_fmt(fmt) "SCMI Notifications BASE - " fmt
9
10 #include <linux/module.h>
11 #include <linux/scmi_protocol.h>
12
13 #include "common.h"
14 #include "notify.h"
15
16 #define SCMI_BASE_NUM_SOURCES 1
17 #define SCMI_BASE_MAX_CMD_ERR_COUNT 1024
18
19 enum scmi_base_protocol_cmd {
20 BASE_DISCOVER_VENDOR = 0x3,
21 BASE_DISCOVER_SUB_VENDOR = 0x4,
22 BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
23 BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
24 BASE_DISCOVER_AGENT = 0x7,
25 BASE_NOTIFY_ERRORS = 0x8,
26 BASE_SET_DEVICE_PERMISSIONS = 0x9,
27 BASE_SET_PROTOCOL_PERMISSIONS = 0xa,
28 BASE_RESET_AGENT_CONFIGURATION = 0xb,
29 };
30
31 struct scmi_msg_resp_base_attributes {
32 u8 num_protocols;
33 u8 num_agents;
34 __le16 reserved;
35 };
36
37 struct scmi_msg_resp_base_discover_agent {
38 __le32 agent_id;
39 u8 name[SCMI_SHORT_NAME_MAX_SIZE];
40 };
41
42
43 struct scmi_msg_base_error_notify {
44 __le32 event_control;
45 #define BASE_TP_NOTIFY_ALL BIT(0)
46 };
47
48 struct scmi_base_error_notify_payld {
49 __le32 agent_id;
50 __le32 error_status;
51 #define IS_FATAL_ERROR(x) ((x) & BIT(31))
52 #define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x))
53 __le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT];
54 };
55
56 /**
57 * scmi_base_attributes_get() - gets the implementation details
58 * that are associated with the base protocol.
59 *
60 * @ph: SCMI protocol handle
61 *
62 * Return: 0 on success, else appropriate SCMI error.
63 */
scmi_base_attributes_get(const struct scmi_protocol_handle * ph)64 static int scmi_base_attributes_get(const struct scmi_protocol_handle *ph)
65 {
66 int ret;
67 struct scmi_xfer *t;
68 struct scmi_msg_resp_base_attributes *attr_info;
69 struct scmi_revision_info *rev = ph->get_priv(ph);
70
71 ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
72 0, sizeof(*attr_info), &t);
73 if (ret)
74 return ret;
75
76 ret = ph->xops->do_xfer(ph, t);
77 if (!ret) {
78 attr_info = t->rx.buf;
79 rev->num_protocols = attr_info->num_protocols;
80 rev->num_agents = attr_info->num_agents;
81 }
82
83 ph->xops->xfer_put(ph, t);
84
85 return ret;
86 }
87
88 /**
89 * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
90 *
91 * @ph: SCMI protocol handle
92 * @sub_vendor: specify true if sub-vendor ID is needed
93 *
94 * Return: 0 on success, else appropriate SCMI error.
95 */
96 static int
scmi_base_vendor_id_get(const struct scmi_protocol_handle * ph,bool sub_vendor)97 scmi_base_vendor_id_get(const struct scmi_protocol_handle *ph, bool sub_vendor)
98 {
99 u8 cmd;
100 int ret, size;
101 char *vendor_id;
102 struct scmi_xfer *t;
103 struct scmi_revision_info *rev = ph->get_priv(ph);
104
105
106 if (sub_vendor) {
107 cmd = BASE_DISCOVER_SUB_VENDOR;
108 vendor_id = rev->sub_vendor_id;
109 size = ARRAY_SIZE(rev->sub_vendor_id);
110 } else {
111 cmd = BASE_DISCOVER_VENDOR;
112 vendor_id = rev->vendor_id;
113 size = ARRAY_SIZE(rev->vendor_id);
114 }
115
116 ret = ph->xops->xfer_get_init(ph, cmd, 0, size, &t);
117 if (ret)
118 return ret;
119
120 ret = ph->xops->do_xfer(ph, t);
121 if (!ret)
122 strscpy(vendor_id, t->rx.buf, size);
123
124 ph->xops->xfer_put(ph, t);
125
126 return ret;
127 }
128
129 /**
130 * scmi_base_implementation_version_get() - gets a vendor-specific
131 * implementation 32-bit version. The format of the version number is
132 * vendor-specific
133 *
134 * @ph: SCMI protocol handle
135 *
136 * Return: 0 on success, else appropriate SCMI error.
137 */
138 static int
scmi_base_implementation_version_get(const struct scmi_protocol_handle * ph)139 scmi_base_implementation_version_get(const struct scmi_protocol_handle *ph)
140 {
141 int ret;
142 __le32 *impl_ver;
143 struct scmi_xfer *t;
144 struct scmi_revision_info *rev = ph->get_priv(ph);
145
146 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_IMPLEMENT_VERSION,
147 0, sizeof(*impl_ver), &t);
148 if (ret)
149 return ret;
150
151 ret = ph->xops->do_xfer(ph, t);
152 if (!ret) {
153 impl_ver = t->rx.buf;
154 rev->impl_ver = le32_to_cpu(*impl_ver);
155 }
156
157 ph->xops->xfer_put(ph, t);
158
159 return ret;
160 }
161
162 /**
163 * scmi_base_implementation_list_get() - gets the list of protocols it is
164 * OSPM is allowed to access
165 *
166 * @ph: SCMI protocol handle
167 * @protocols_imp: pointer to hold the list of protocol identifiers
168 *
169 * Return: 0 on success, else appropriate SCMI error.
170 */
171 static int
scmi_base_implementation_list_get(const struct scmi_protocol_handle * ph,u8 * protocols_imp)172 scmi_base_implementation_list_get(const struct scmi_protocol_handle *ph,
173 u8 *protocols_imp)
174 {
175 u8 *list;
176 int ret, loop;
177 struct scmi_xfer *t;
178 __le32 *num_skip, *num_ret;
179 u32 tot_num_ret = 0, loop_num_ret;
180 struct device *dev = ph->dev;
181 struct scmi_revision_info *rev = ph->get_priv(ph);
182
183 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_LIST_PROTOCOLS,
184 sizeof(*num_skip), 0, &t);
185 if (ret)
186 return ret;
187
188 num_skip = t->tx.buf;
189 num_ret = t->rx.buf;
190 list = t->rx.buf + sizeof(*num_ret);
191
192 do {
193 size_t real_list_sz;
194 u32 calc_list_sz;
195
196 /* Set the number of protocols to be skipped/already read */
197 *num_skip = cpu_to_le32(tot_num_ret);
198
199 ret = ph->xops->do_xfer(ph, t);
200 if (ret)
201 break;
202
203 loop_num_ret = le32_to_cpu(*num_ret);
204 if (!loop_num_ret)
205 break;
206
207 if (loop_num_ret > rev->num_protocols - tot_num_ret) {
208 dev_err(dev,
209 "No. Returned protocols > Total protocols.\n");
210 break;
211 }
212
213 if (t->rx.len < (sizeof(u32) * 2)) {
214 dev_err(dev, "Truncated reply - rx.len:%zd\n",
215 t->rx.len);
216 ret = -EPROTO;
217 break;
218 }
219
220 real_list_sz = t->rx.len - sizeof(u32);
221 calc_list_sz = (1 + (loop_num_ret - 1) / sizeof(u32)) *
222 sizeof(u32);
223 if (calc_list_sz != real_list_sz) {
224 dev_warn(dev,
225 "Malformed reply - real_sz:%zd calc_sz:%u (loop_num_ret:%d)\n",
226 real_list_sz, calc_list_sz, loop_num_ret);
227 /*
228 * Bail out if the expected list size is bigger than the
229 * total payload size of the received reply.
230 */
231 if (calc_list_sz > real_list_sz) {
232 ret = -EPROTO;
233 break;
234 }
235 }
236
237 for (loop = 0; loop < loop_num_ret; loop++)
238 protocols_imp[tot_num_ret + loop] = *(list + loop);
239
240 tot_num_ret += loop_num_ret;
241
242 ph->xops->reset_rx_to_maxsz(ph, t);
243 } while (tot_num_ret < rev->num_protocols);
244
245 ph->xops->xfer_put(ph, t);
246
247 return ret;
248 }
249
250 /**
251 * scmi_base_discover_agent_get() - discover the name of an agent
252 *
253 * @ph: SCMI protocol handle
254 * @id: Agent identifier
255 * @name: Agent identifier ASCII string
256 *
257 * An agent id of 0 is reserved to identify the platform itself.
258 * Generally operating system is represented as "OSPM"
259 *
260 * Return: 0 on success, else appropriate SCMI error.
261 */
scmi_base_discover_agent_get(const struct scmi_protocol_handle * ph,int id,char * name)262 static int scmi_base_discover_agent_get(const struct scmi_protocol_handle *ph,
263 int id, char *name)
264 {
265 int ret;
266 struct scmi_msg_resp_base_discover_agent *agent_info;
267 struct scmi_xfer *t;
268
269 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_AGENT,
270 sizeof(__le32), sizeof(*agent_info), &t);
271 if (ret)
272 return ret;
273
274 put_unaligned_le32(id, t->tx.buf);
275
276 ret = ph->xops->do_xfer(ph, t);
277 if (!ret) {
278 agent_info = t->rx.buf;
279 strscpy(name, agent_info->name, SCMI_SHORT_NAME_MAX_SIZE);
280 }
281
282 ph->xops->xfer_put(ph, t);
283
284 return ret;
285 }
286
scmi_base_error_notify(const struct scmi_protocol_handle * ph,bool enable)287 static int scmi_base_error_notify(const struct scmi_protocol_handle *ph,
288 bool enable)
289 {
290 int ret;
291 u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0;
292 struct scmi_xfer *t;
293 struct scmi_msg_base_error_notify *cfg;
294
295 ret = ph->xops->xfer_get_init(ph, BASE_NOTIFY_ERRORS,
296 sizeof(*cfg), 0, &t);
297 if (ret)
298 return ret;
299
300 cfg = t->tx.buf;
301 cfg->event_control = cpu_to_le32(evt_cntl);
302
303 ret = ph->xops->do_xfer(ph, t);
304
305 ph->xops->xfer_put(ph, t);
306 return ret;
307 }
308
scmi_base_set_notify_enabled(const struct scmi_protocol_handle * ph,u8 evt_id,u32 src_id,bool enable)309 static int scmi_base_set_notify_enabled(const struct scmi_protocol_handle *ph,
310 u8 evt_id, u32 src_id, bool enable)
311 {
312 int ret;
313
314 ret = scmi_base_error_notify(ph, enable);
315 if (ret)
316 pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret);
317
318 return ret;
319 }
320
scmi_base_fill_custom_report(const struct scmi_protocol_handle * ph,u8 evt_id,ktime_t timestamp,const void * payld,size_t payld_sz,void * report,u32 * src_id)321 static void *scmi_base_fill_custom_report(const struct scmi_protocol_handle *ph,
322 u8 evt_id, ktime_t timestamp,
323 const void *payld, size_t payld_sz,
324 void *report, u32 *src_id)
325 {
326 int i;
327 const struct scmi_base_error_notify_payld *p = payld;
328 struct scmi_base_error_report *r = report;
329
330 /*
331 * BaseError notification payload is variable in size but
332 * up to a maximum length determined by the struct ponted by p.
333 * Instead payld_sz is the effective length of this notification
334 * payload so cannot be greater of the maximum allowed size as
335 * pointed by p.
336 */
337 if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz)
338 return NULL;
339
340 r->timestamp = timestamp;
341 r->agent_id = le32_to_cpu(p->agent_id);
342 r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status));
343 r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status));
344 for (i = 0; i < r->cmd_count; i++)
345 r->reports[i] = le64_to_cpu(p->msg_reports[i]);
346 *src_id = 0;
347
348 return r;
349 }
350
351 static const struct scmi_event base_events[] = {
352 {
353 .id = SCMI_EVENT_BASE_ERROR_EVENT,
354 .max_payld_sz = sizeof(struct scmi_base_error_notify_payld),
355 .max_report_sz = sizeof(struct scmi_base_error_report) +
356 SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64),
357 },
358 };
359
360 static const struct scmi_event_ops base_event_ops = {
361 .set_notify_enabled = scmi_base_set_notify_enabled,
362 .fill_custom_report = scmi_base_fill_custom_report,
363 };
364
365 static const struct scmi_protocol_events base_protocol_events = {
366 .queue_sz = 4 * SCMI_PROTO_QUEUE_SZ,
367 .ops = &base_event_ops,
368 .evts = base_events,
369 .num_events = ARRAY_SIZE(base_events),
370 .num_sources = SCMI_BASE_NUM_SOURCES,
371 };
372
scmi_base_protocol_init(const struct scmi_protocol_handle * ph)373 static int scmi_base_protocol_init(const struct scmi_protocol_handle *ph)
374 {
375 int id, ret;
376 u8 *prot_imp;
377 u32 version;
378 char name[SCMI_SHORT_NAME_MAX_SIZE];
379 struct device *dev = ph->dev;
380 struct scmi_revision_info *rev = scmi_revision_area_get(ph);
381
382 ret = ph->xops->version_get(ph, &version);
383 if (ret)
384 return ret;
385
386 rev->major_ver = PROTOCOL_REV_MAJOR(version),
387 rev->minor_ver = PROTOCOL_REV_MINOR(version);
388 ph->set_priv(ph, rev);
389
390 ret = scmi_base_attributes_get(ph);
391 if (ret)
392 return ret;
393
394 prot_imp = devm_kcalloc(dev, rev->num_protocols, sizeof(u8),
395 GFP_KERNEL);
396 if (!prot_imp)
397 return -ENOMEM;
398
399 scmi_base_vendor_id_get(ph, false);
400 scmi_base_vendor_id_get(ph, true);
401 scmi_base_implementation_version_get(ph);
402 scmi_base_implementation_list_get(ph, prot_imp);
403
404 scmi_setup_protocol_implemented(ph, prot_imp);
405
406 dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
407 rev->major_ver, rev->minor_ver, rev->vendor_id,
408 rev->sub_vendor_id, rev->impl_ver);
409 dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
410 rev->num_agents);
411
412 for (id = 0; id < rev->num_agents; id++) {
413 scmi_base_discover_agent_get(ph, id, name);
414 dev_dbg(dev, "Agent %d: %s\n", id, name);
415 }
416
417 return 0;
418 }
419
420 static const struct scmi_protocol scmi_base = {
421 .id = SCMI_PROTOCOL_BASE,
422 .owner = NULL,
423 .instance_init = &scmi_base_protocol_init,
424 .ops = NULL,
425 .events = &base_protocol_events,
426 };
427
428 DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(base, scmi_base)
429