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