Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * System Control and Management Interface (SCMI) Reset Protocol
4 *
5 * Copyright (C) 2019-2022 ARM Ltd.
6 */
7
8#define pr_fmt(fmt) "SCMI Notifications RESET - " fmt
9
10#include <linux/module.h>
11#include <linux/scmi_protocol.h>
12
13#include "protocols.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 0x30001
18
19enum scmi_reset_protocol_cmd {
20 RESET_DOMAIN_ATTRIBUTES = 0x3,
21 RESET = 0x4,
22 RESET_NOTIFY = 0x5,
23 RESET_DOMAIN_NAME_GET = 0x6,
24};
25
26#define NUM_RESET_DOMAIN_MASK 0xffff
27#define RESET_NOTIFY_ENABLE BIT(0)
28
29struct scmi_msg_resp_reset_domain_attributes {
30 __le32 attributes;
31#define SUPPORTS_ASYNC_RESET(x) ((x) & BIT(31))
32#define SUPPORTS_NOTIFY_RESET(x) ((x) & BIT(30))
33#define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(29))
34 __le32 latency;
35 u8 name[SCMI_SHORT_NAME_MAX_SIZE];
36};
37
38struct scmi_msg_reset_domain_reset {
39 __le32 domain_id;
40 __le32 flags;
41#define AUTONOMOUS_RESET BIT(0)
42#define EXPLICIT_RESET_ASSERT BIT(1)
43#define ASYNCHRONOUS_RESET BIT(2)
44 __le32 reset_state;
45#define ARCH_COLD_RESET 0
46};
47
48struct scmi_msg_reset_notify {
49 __le32 id;
50 __le32 event_control;
51#define RESET_TP_NOTIFY_ALL BIT(0)
52};
53
54struct scmi_reset_issued_notify_payld {
55 __le32 agent_id;
56 __le32 domain_id;
57 __le32 reset_state;
58};
59
60struct reset_dom_info {
61 bool async_reset;
62 bool reset_notify;
63 u32 latency_us;
64 char name[SCMI_MAX_STR_SIZE];
65};
66
67struct scmi_reset_info {
68 int num_domains;
69 bool notify_reset_cmd;
70 struct reset_dom_info *dom_info;
71};
72
73static int scmi_reset_attributes_get(const struct scmi_protocol_handle *ph,
74 struct scmi_reset_info *pi)
75{
76 int ret;
77 struct scmi_xfer *t;
78 u32 attr;
79
80 ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
81 0, sizeof(attr), &t);
82 if (ret)
83 return ret;
84
85 ret = ph->xops->do_xfer(ph, t);
86 if (!ret) {
87 attr = get_unaligned_le32(t->rx.buf);
88 pi->num_domains = attr & NUM_RESET_DOMAIN_MASK;
89 }
90
91 ph->xops->xfer_put(ph, t);
92
93 if (!ret)
94 if (!ph->hops->protocol_msg_check(ph, RESET_NOTIFY, NULL))
95 pi->notify_reset_cmd = true;
96
97 return ret;
98}
99
100static struct reset_dom_info *
101scmi_reset_domain_lookup(const struct scmi_protocol_handle *ph, u32 domain)
102{
103 struct scmi_reset_info *pi = ph->get_priv(ph);
104
105 if (domain >= pi->num_domains)
106 return ERR_PTR(-EINVAL);
107
108 return pi->dom_info + domain;
109}
110
111static int
112scmi_reset_domain_attributes_get(const struct scmi_protocol_handle *ph,
113 struct scmi_reset_info *pinfo, u32 domain)
114{
115 int ret;
116 u32 attributes;
117 struct scmi_xfer *t;
118 struct scmi_msg_resp_reset_domain_attributes *attr;
119 struct reset_dom_info *dom_info = pinfo->dom_info + domain;
120
121 ret = ph->xops->xfer_get_init(ph, RESET_DOMAIN_ATTRIBUTES,
122 sizeof(domain), sizeof(*attr), &t);
123 if (ret)
124 return ret;
125
126 put_unaligned_le32(domain, t->tx.buf);
127 attr = t->rx.buf;
128
129 ret = ph->xops->do_xfer(ph, t);
130 if (!ret) {
131 attributes = le32_to_cpu(attr->attributes);
132
133 dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
134 if (pinfo->notify_reset_cmd)
135 dom_info->reset_notify =
136 SUPPORTS_NOTIFY_RESET(attributes);
137 dom_info->latency_us = le32_to_cpu(attr->latency);
138 if (dom_info->latency_us == U32_MAX)
139 dom_info->latency_us = 0;
140 strscpy(dom_info->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE);
141 }
142
143 ph->xops->xfer_put(ph, t);
144
145 /*
146 * If supported overwrite short name with the extended one;
147 * on error just carry on and use already provided short name.
148 */
149 if (!ret && PROTOCOL_REV_MAJOR(ph->version) >= 0x3 &&
150 SUPPORTS_EXTENDED_NAMES(attributes))
151 ph->hops->extended_name_get(ph, RESET_DOMAIN_NAME_GET, domain,
152 NULL, dom_info->name,
153 SCMI_MAX_STR_SIZE);
154
155 return ret;
156}
157
158static int scmi_reset_num_domains_get(const struct scmi_protocol_handle *ph)
159{
160 struct scmi_reset_info *pi = ph->get_priv(ph);
161
162 return pi->num_domains;
163}
164
165static const char *
166scmi_reset_name_get(const struct scmi_protocol_handle *ph, u32 domain)
167{
168 struct reset_dom_info *dom_info;
169
170 dom_info = scmi_reset_domain_lookup(ph, domain);
171 if (IS_ERR(dom_info))
172 return "unknown";
173
174 return dom_info->name;
175}
176
177static int scmi_reset_latency_get(const struct scmi_protocol_handle *ph,
178 u32 domain)
179{
180 struct reset_dom_info *dom_info;
181
182 dom_info = scmi_reset_domain_lookup(ph, domain);
183 if (IS_ERR(dom_info))
184 return PTR_ERR(dom_info);
185
186 return dom_info->latency_us;
187}
188
189static int scmi_domain_reset(const struct scmi_protocol_handle *ph, u32 domain,
190 u32 flags, u32 state)
191{
192 int ret;
193 struct scmi_xfer *t;
194 struct scmi_msg_reset_domain_reset *dom;
195 struct reset_dom_info *dom_info;
196
197 dom_info = scmi_reset_domain_lookup(ph, domain);
198 if (IS_ERR(dom_info))
199 return PTR_ERR(dom_info);
200
201 if (dom_info->async_reset && flags & AUTONOMOUS_RESET)
202 flags |= ASYNCHRONOUS_RESET;
203
204 ret = ph->xops->xfer_get_init(ph, RESET, sizeof(*dom), 0, &t);
205 if (ret)
206 return ret;
207
208 dom = t->tx.buf;
209 dom->domain_id = cpu_to_le32(domain);
210 dom->flags = cpu_to_le32(flags);
211 dom->reset_state = cpu_to_le32(state);
212
213 if (flags & ASYNCHRONOUS_RESET)
214 ret = ph->xops->do_xfer_with_response(ph, t);
215 else
216 ret = ph->xops->do_xfer(ph, t);
217
218 ph->xops->xfer_put(ph, t);
219 return ret;
220}
221
222static int scmi_reset_domain_reset(const struct scmi_protocol_handle *ph,
223 u32 domain)
224{
225 return scmi_domain_reset(ph, domain, AUTONOMOUS_RESET,
226 ARCH_COLD_RESET);
227}
228
229static int
230scmi_reset_domain_assert(const struct scmi_protocol_handle *ph, u32 domain)
231{
232 return scmi_domain_reset(ph, domain, EXPLICIT_RESET_ASSERT,
233 ARCH_COLD_RESET);
234}
235
236static int
237scmi_reset_domain_deassert(const struct scmi_protocol_handle *ph, u32 domain)
238{
239 return scmi_domain_reset(ph, domain, 0, ARCH_COLD_RESET);
240}
241
242static const struct scmi_reset_proto_ops reset_proto_ops = {
243 .num_domains_get = scmi_reset_num_domains_get,
244 .name_get = scmi_reset_name_get,
245 .latency_get = scmi_reset_latency_get,
246 .reset = scmi_reset_domain_reset,
247 .assert = scmi_reset_domain_assert,
248 .deassert = scmi_reset_domain_deassert,
249};
250
251static bool scmi_reset_notify_supported(const struct scmi_protocol_handle *ph,
252 u8 evt_id, u32 src_id)
253{
254 struct reset_dom_info *dom_info;
255
256 if (evt_id != SCMI_EVENT_RESET_ISSUED)
257 return false;
258
259 dom_info = scmi_reset_domain_lookup(ph, src_id);
260 if (IS_ERR(dom_info))
261 return false;
262
263 return dom_info->reset_notify;
264}
265
266static int scmi_reset_notify(const struct scmi_protocol_handle *ph,
267 u32 domain_id, bool enable)
268{
269 int ret;
270 u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0;
271 struct scmi_xfer *t;
272 struct scmi_msg_reset_notify *cfg;
273
274 ret = ph->xops->xfer_get_init(ph, RESET_NOTIFY, sizeof(*cfg), 0, &t);
275 if (ret)
276 return ret;
277
278 cfg = t->tx.buf;
279 cfg->id = cpu_to_le32(domain_id);
280 cfg->event_control = cpu_to_le32(evt_cntl);
281
282 ret = ph->xops->do_xfer(ph, t);
283
284 ph->xops->xfer_put(ph, t);
285 return ret;
286}
287
288static int scmi_reset_set_notify_enabled(const struct scmi_protocol_handle *ph,
289 u8 evt_id, u32 src_id, bool enable)
290{
291 int ret;
292
293 ret = scmi_reset_notify(ph, src_id, enable);
294 if (ret)
295 pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
296 evt_id, src_id, ret);
297
298 return ret;
299}
300
301static void *
302scmi_reset_fill_custom_report(const struct scmi_protocol_handle *ph,
303 u8 evt_id, ktime_t timestamp,
304 const void *payld, size_t payld_sz,
305 void *report, u32 *src_id)
306{
307 const struct scmi_reset_issued_notify_payld *p = payld;
308 struct scmi_reset_issued_report *r = report;
309
310 if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz)
311 return NULL;
312
313 r->timestamp = timestamp;
314 r->agent_id = le32_to_cpu(p->agent_id);
315 r->domain_id = le32_to_cpu(p->domain_id);
316 r->reset_state = le32_to_cpu(p->reset_state);
317 *src_id = r->domain_id;
318
319 return r;
320}
321
322static int scmi_reset_get_num_sources(const struct scmi_protocol_handle *ph)
323{
324 struct scmi_reset_info *pinfo = ph->get_priv(ph);
325
326 if (!pinfo)
327 return -EINVAL;
328
329 return pinfo->num_domains;
330}
331
332static const struct scmi_event reset_events[] = {
333 {
334 .id = SCMI_EVENT_RESET_ISSUED,
335 .max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld),
336 .max_report_sz = sizeof(struct scmi_reset_issued_report),
337 },
338};
339
340static const struct scmi_event_ops reset_event_ops = {
341 .is_notify_supported = scmi_reset_notify_supported,
342 .get_num_sources = scmi_reset_get_num_sources,
343 .set_notify_enabled = scmi_reset_set_notify_enabled,
344 .fill_custom_report = scmi_reset_fill_custom_report,
345};
346
347static const struct scmi_protocol_events reset_protocol_events = {
348 .queue_sz = SCMI_PROTO_QUEUE_SZ,
349 .ops = &reset_event_ops,
350 .evts = reset_events,
351 .num_events = ARRAY_SIZE(reset_events),
352};
353
354static int scmi_reset_protocol_init(const struct scmi_protocol_handle *ph)
355{
356 int domain, ret;
357 struct scmi_reset_info *pinfo;
358
359 dev_dbg(ph->dev, "Reset Version %d.%d\n",
360 PROTOCOL_REV_MAJOR(ph->version), PROTOCOL_REV_MINOR(ph->version));
361
362 pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
363 if (!pinfo)
364 return -ENOMEM;
365
366 ret = scmi_reset_attributes_get(ph, pinfo);
367 if (ret)
368 return ret;
369
370 pinfo->dom_info = devm_kcalloc(ph->dev, pinfo->num_domains,
371 sizeof(*pinfo->dom_info), GFP_KERNEL);
372 if (!pinfo->dom_info)
373 return -ENOMEM;
374
375 for (domain = 0; domain < pinfo->num_domains; domain++)
376 scmi_reset_domain_attributes_get(ph, pinfo, domain);
377
378 return ph->set_priv(ph, pinfo);
379}
380
381static const struct scmi_protocol scmi_reset = {
382 .id = SCMI_PROTOCOL_RESET,
383 .owner = THIS_MODULE,
384 .instance_init = &scmi_reset_protocol_init,
385 .ops = &reset_proto_ops,
386 .events = &reset_protocol_events,
387 .supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
388};
389
390DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(reset, scmi_reset)