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/* Updated only after ALL the mandatory features for that version are merged */
17#define SCMI_PROTOCOL_SUPPORTED_VERSION 0x20000
18
19#define SCMI_BASE_NUM_SOURCES 1
20#define SCMI_BASE_MAX_CMD_ERR_COUNT 1024
21
22enum scmi_base_protocol_cmd {
23 BASE_DISCOVER_VENDOR = 0x3,
24 BASE_DISCOVER_SUB_VENDOR = 0x4,
25 BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
26 BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
27 BASE_DISCOVER_AGENT = 0x7,
28 BASE_NOTIFY_ERRORS = 0x8,
29 BASE_SET_DEVICE_PERMISSIONS = 0x9,
30 BASE_SET_PROTOCOL_PERMISSIONS = 0xa,
31 BASE_RESET_AGENT_CONFIGURATION = 0xb,
32};
33
34struct scmi_msg_resp_base_attributes {
35 u8 num_protocols;
36 u8 num_agents;
37 __le16 reserved;
38};
39
40struct scmi_msg_resp_base_discover_agent {
41 __le32 agent_id;
42 u8 name[SCMI_SHORT_NAME_MAX_SIZE];
43};
44
45
46struct scmi_msg_base_error_notify {
47 __le32 event_control;
48#define BASE_TP_NOTIFY_ALL BIT(0)
49};
50
51struct scmi_base_error_notify_payld {
52 __le32 agent_id;
53 __le32 error_status;
54#define IS_FATAL_ERROR(x) ((x) & BIT(31))
55#define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x))
56 __le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT];
57};
58
59/**
60 * scmi_base_attributes_get() - gets the implementation details
61 * that are associated with the base protocol.
62 *
63 * @ph: SCMI protocol handle
64 *
65 * Return: 0 on success, else appropriate SCMI error.
66 */
67static int scmi_base_attributes_get(const struct scmi_protocol_handle *ph)
68{
69 int ret;
70 struct scmi_xfer *t;
71 struct scmi_msg_resp_base_attributes *attr_info;
72 struct scmi_revision_info *rev = ph->get_priv(ph);
73
74 ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
75 0, sizeof(*attr_info), &t);
76 if (ret)
77 return ret;
78
79 ret = ph->xops->do_xfer(ph, t);
80 if (!ret) {
81 attr_info = t->rx.buf;
82 rev->num_protocols = attr_info->num_protocols;
83 rev->num_agents = attr_info->num_agents;
84 }
85
86 ph->xops->xfer_put(ph, t);
87
88 return ret;
89}
90
91/**
92 * scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
93 *
94 * @ph: SCMI protocol handle
95 * @sub_vendor: specify true if sub-vendor ID is needed
96 *
97 * Return: 0 on success, else appropriate SCMI error.
98 */
99static int
100scmi_base_vendor_id_get(const struct scmi_protocol_handle *ph, bool sub_vendor)
101{
102 u8 cmd;
103 int ret, size;
104 char *vendor_id;
105 struct scmi_xfer *t;
106 struct scmi_revision_info *rev = ph->get_priv(ph);
107
108
109 if (sub_vendor) {
110 cmd = BASE_DISCOVER_SUB_VENDOR;
111 vendor_id = rev->sub_vendor_id;
112 size = ARRAY_SIZE(rev->sub_vendor_id);
113 } else {
114 cmd = BASE_DISCOVER_VENDOR;
115 vendor_id = rev->vendor_id;
116 size = ARRAY_SIZE(rev->vendor_id);
117 }
118
119 ret = ph->xops->xfer_get_init(ph, cmd, 0, size, &t);
120 if (ret)
121 return ret;
122
123 ret = ph->xops->do_xfer(ph, t);
124 if (!ret)
125 strscpy(vendor_id, t->rx.buf, size);
126
127 ph->xops->xfer_put(ph, t);
128
129 return ret;
130}
131
132/**
133 * scmi_base_implementation_version_get() - gets a vendor-specific
134 * implementation 32-bit version. The format of the version number is
135 * vendor-specific
136 *
137 * @ph: SCMI protocol handle
138 *
139 * Return: 0 on success, else appropriate SCMI error.
140 */
141static int
142scmi_base_implementation_version_get(const struct scmi_protocol_handle *ph)
143{
144 int ret;
145 __le32 *impl_ver;
146 struct scmi_xfer *t;
147 struct scmi_revision_info *rev = ph->get_priv(ph);
148
149 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_IMPLEMENT_VERSION,
150 0, sizeof(*impl_ver), &t);
151 if (ret)
152 return ret;
153
154 ret = ph->xops->do_xfer(ph, t);
155 if (!ret) {
156 impl_ver = t->rx.buf;
157 rev->impl_ver = le32_to_cpu(*impl_ver);
158 }
159
160 ph->xops->xfer_put(ph, t);
161
162 return ret;
163}
164
165/**
166 * scmi_base_implementation_list_get() - gets the list of protocols it is
167 * OSPM is allowed to access
168 *
169 * @ph: SCMI protocol handle
170 * @protocols_imp: pointer to hold the list of protocol identifiers
171 *
172 * Return: 0 on success, else appropriate SCMI error.
173 */
174static int
175scmi_base_implementation_list_get(const struct scmi_protocol_handle *ph,
176 u8 *protocols_imp)
177{
178 u8 *list;
179 int ret, loop;
180 struct scmi_xfer *t;
181 __le32 *num_skip, *num_ret;
182 u32 tot_num_ret = 0, loop_num_ret;
183 struct device *dev = ph->dev;
184 struct scmi_revision_info *rev = ph->get_priv(ph);
185
186 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_LIST_PROTOCOLS,
187 sizeof(*num_skip), 0, &t);
188 if (ret)
189 return ret;
190
191 num_skip = t->tx.buf;
192 num_ret = t->rx.buf;
193 list = t->rx.buf + sizeof(*num_ret);
194
195 do {
196 size_t real_list_sz;
197 u32 calc_list_sz;
198
199 /* Set the number of protocols to be skipped/already read */
200 *num_skip = cpu_to_le32(tot_num_ret);
201
202 ret = ph->xops->do_xfer(ph, t);
203 if (ret)
204 break;
205
206 loop_num_ret = le32_to_cpu(*num_ret);
207 if (!loop_num_ret)
208 break;
209
210 if (loop_num_ret > rev->num_protocols - tot_num_ret) {
211 dev_err(dev,
212 "No. Returned protocols > Total protocols.\n");
213 break;
214 }
215
216 if (t->rx.len < (sizeof(u32) * 2)) {
217 dev_err(dev, "Truncated reply - rx.len:%zd\n",
218 t->rx.len);
219 ret = -EPROTO;
220 break;
221 }
222
223 real_list_sz = t->rx.len - sizeof(u32);
224 calc_list_sz = (1 + (loop_num_ret - 1) / sizeof(u32)) *
225 sizeof(u32);
226 if (calc_list_sz != real_list_sz) {
227 dev_warn(dev,
228 "Malformed reply - real_sz:%zd calc_sz:%u (loop_num_ret:%d)\n",
229 real_list_sz, calc_list_sz, loop_num_ret);
230 /*
231 * Bail out if the expected list size is bigger than the
232 * total payload size of the received reply.
233 */
234 if (calc_list_sz > real_list_sz) {
235 ret = -EPROTO;
236 break;
237 }
238 }
239
240 for (loop = 0; loop < loop_num_ret; loop++)
241 protocols_imp[tot_num_ret + loop] = *(list + loop);
242
243 tot_num_ret += loop_num_ret;
244
245 ph->xops->reset_rx_to_maxsz(ph, t);
246 } while (tot_num_ret < rev->num_protocols);
247
248 ph->xops->xfer_put(ph, t);
249
250 return ret;
251}
252
253/**
254 * scmi_base_discover_agent_get() - discover the name of an agent
255 *
256 * @ph: SCMI protocol handle
257 * @id: Agent identifier
258 * @name: Agent identifier ASCII string
259 *
260 * An agent id of 0 is reserved to identify the platform itself.
261 * Generally operating system is represented as "OSPM"
262 *
263 * Return: 0 on success, else appropriate SCMI error.
264 */
265static int scmi_base_discover_agent_get(const struct scmi_protocol_handle *ph,
266 int id, char *name)
267{
268 int ret;
269 struct scmi_msg_resp_base_discover_agent *agent_info;
270 struct scmi_xfer *t;
271
272 ret = ph->xops->xfer_get_init(ph, BASE_DISCOVER_AGENT,
273 sizeof(__le32), sizeof(*agent_info), &t);
274 if (ret)
275 return ret;
276
277 put_unaligned_le32(val: id, p: t->tx.buf);
278
279 ret = ph->xops->do_xfer(ph, t);
280 if (!ret) {
281 agent_info = t->rx.buf;
282 strscpy(name, agent_info->name, SCMI_SHORT_NAME_MAX_SIZE);
283 }
284
285 ph->xops->xfer_put(ph, t);
286
287 return ret;
288}
289
290static int scmi_base_error_notify(const struct scmi_protocol_handle *ph,
291 bool enable)
292{
293 int ret;
294 u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0;
295 struct scmi_xfer *t;
296 struct scmi_msg_base_error_notify *cfg;
297
298 ret = ph->xops->xfer_get_init(ph, BASE_NOTIFY_ERRORS,
299 sizeof(*cfg), 0, &t);
300 if (ret)
301 return ret;
302
303 cfg = t->tx.buf;
304 cfg->event_control = cpu_to_le32(evt_cntl);
305
306 ret = ph->xops->do_xfer(ph, t);
307
308 ph->xops->xfer_put(ph, t);
309 return ret;
310}
311
312static int scmi_base_set_notify_enabled(const struct scmi_protocol_handle *ph,
313 u8 evt_id, u32 src_id, bool enable)
314{
315 int ret;
316
317 ret = scmi_base_error_notify(ph, enable);
318 if (ret)
319 pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret);
320
321 return ret;
322}
323
324static void *scmi_base_fill_custom_report(const struct scmi_protocol_handle *ph,
325 u8 evt_id, ktime_t timestamp,
326 const void *payld, size_t payld_sz,
327 void *report, u32 *src_id)
328{
329 int i;
330 const struct scmi_base_error_notify_payld *p = payld;
331 struct scmi_base_error_report *r = report;
332
333 /*
334 * BaseError notification payload is variable in size but
335 * up to a maximum length determined by the struct ponted by p.
336 * Instead payld_sz is the effective length of this notification
337 * payload so cannot be greater of the maximum allowed size as
338 * pointed by p.
339 */
340 if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz)
341 return NULL;
342
343 r->timestamp = timestamp;
344 r->agent_id = le32_to_cpu(p->agent_id);
345 r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status));
346 r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status));
347 for (i = 0; i < r->cmd_count; i++)
348 r->reports[i] = le64_to_cpu(p->msg_reports[i]);
349 *src_id = 0;
350
351 return r;
352}
353
354static const struct scmi_event base_events[] = {
355 {
356 .id = SCMI_EVENT_BASE_ERROR_EVENT,
357 .max_payld_sz = sizeof(struct scmi_base_error_notify_payld),
358 .max_report_sz = sizeof(struct scmi_base_error_report) +
359 SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64),
360 },
361};
362
363static const struct scmi_event_ops base_event_ops = {
364 .set_notify_enabled = scmi_base_set_notify_enabled,
365 .fill_custom_report = scmi_base_fill_custom_report,
366};
367
368static const struct scmi_protocol_events base_protocol_events = {
369 .queue_sz = 4 * SCMI_PROTO_QUEUE_SZ,
370 .ops = &base_event_ops,
371 .evts = base_events,
372 .num_events = ARRAY_SIZE(base_events),
373 .num_sources = SCMI_BASE_NUM_SOURCES,
374};
375
376static int scmi_base_protocol_init(const struct scmi_protocol_handle *ph)
377{
378 int id, ret;
379 u8 *prot_imp;
380 u32 version;
381 char name[SCMI_SHORT_NAME_MAX_SIZE];
382 struct device *dev = ph->dev;
383 struct scmi_revision_info *rev = scmi_revision_area_get(ph);
384
385 ret = ph->xops->version_get(ph, &version);
386 if (ret)
387 return ret;
388
389 rev->major_ver = PROTOCOL_REV_MAJOR(version),
390 rev->minor_ver = PROTOCOL_REV_MINOR(version);
391 ph->set_priv(ph, rev, version);
392
393 ret = scmi_base_attributes_get(ph);
394 if (ret)
395 return ret;
396
397 prot_imp = devm_kcalloc(dev, n: rev->num_protocols, size: sizeof(u8),
398 GFP_KERNEL);
399 if (!prot_imp)
400 return -ENOMEM;
401
402 scmi_base_vendor_id_get(ph, sub_vendor: false);
403 scmi_base_vendor_id_get(ph, sub_vendor: true);
404 scmi_base_implementation_version_get(ph);
405 scmi_base_implementation_list_get(ph, protocols_imp: prot_imp);
406
407 scmi_setup_protocol_implemented(ph, prot_imp);
408
409 dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
410 rev->major_ver, rev->minor_ver, rev->vendor_id,
411 rev->sub_vendor_id, rev->impl_ver);
412 dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
413 rev->num_agents);
414
415 for (id = 0; id < rev->num_agents; id++) {
416 scmi_base_discover_agent_get(ph, id, name);
417 dev_dbg(dev, "Agent %d: %s\n", id, name);
418 }
419
420 return 0;
421}
422
423static const struct scmi_protocol scmi_base = {
424 .id = SCMI_PROTOCOL_BASE,
425 .owner = NULL,
426 .instance_init = &scmi_base_protocol_init,
427 .ops = NULL,
428 .events = &base_protocol_events,
429 .supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
430};
431
432DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(base, scmi_base)
433

source code of linux/drivers/firmware/arm_scmi/base.c