1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2017, Linaro Ltd.
4 */
5#include <linux/firmware.h>
6#include <linux/module.h>
7#include <linux/notifier.h>
8#include <linux/slab.h>
9#include <linux/interrupt.h>
10#include <linux/io.h>
11#include <linux/of_irq.h>
12#include <linux/platform_device.h>
13#include <linux/remoteproc/qcom_rproc.h>
14#include <linux/rpmsg.h>
15
16#include "qcom_common.h"
17
18static BLOCKING_NOTIFIER_HEAD(sysmon_notifiers);
19
20struct qcom_sysmon {
21 struct rproc_subdev subdev;
22 struct rproc *rproc;
23
24 int state;
25 struct mutex state_lock;
26
27 struct list_head node;
28
29 const char *name;
30
31 int shutdown_irq;
32 int ssctl_version;
33 int ssctl_instance;
34
35 struct notifier_block nb;
36
37 struct device *dev;
38
39 struct rpmsg_endpoint *ept;
40 struct completion comp;
41 struct completion ind_comp;
42 struct completion shutdown_comp;
43 struct completion ssctl_comp;
44 struct mutex lock;
45
46 bool ssr_ack;
47 bool shutdown_acked;
48
49 struct qmi_handle qmi;
50 struct sockaddr_qrtr ssctl;
51};
52
53enum {
54 SSCTL_SSR_EVENT_BEFORE_POWERUP,
55 SSCTL_SSR_EVENT_AFTER_POWERUP,
56 SSCTL_SSR_EVENT_BEFORE_SHUTDOWN,
57 SSCTL_SSR_EVENT_AFTER_SHUTDOWN,
58};
59
60static const char * const sysmon_state_string[] = {
61 [SSCTL_SSR_EVENT_BEFORE_POWERUP] = "before_powerup",
62 [SSCTL_SSR_EVENT_AFTER_POWERUP] = "after_powerup",
63 [SSCTL_SSR_EVENT_BEFORE_SHUTDOWN] = "before_shutdown",
64 [SSCTL_SSR_EVENT_AFTER_SHUTDOWN] = "after_shutdown",
65};
66
67struct sysmon_event {
68 const char *subsys_name;
69 u32 ssr_event;
70};
71
72static DEFINE_MUTEX(sysmon_lock);
73static LIST_HEAD(sysmon_list);
74
75/**
76 * sysmon_send_event() - send notification of other remote's SSR event
77 * @sysmon: sysmon context
78 * @event: sysmon event context
79 */
80static void sysmon_send_event(struct qcom_sysmon *sysmon,
81 const struct sysmon_event *event)
82{
83 char req[50];
84 int len;
85 int ret;
86
87 len = snprintf(buf: req, size: sizeof(req), fmt: "ssr:%s:%s", event->subsys_name,
88 sysmon_state_string[event->ssr_event]);
89 if (len >= sizeof(req))
90 return;
91
92 mutex_lock(&sysmon->lock);
93 reinit_completion(x: &sysmon->comp);
94 sysmon->ssr_ack = false;
95
96 ret = rpmsg_send(ept: sysmon->ept, data: req, len);
97 if (ret < 0) {
98 dev_err(sysmon->dev, "failed to send sysmon event\n");
99 goto out_unlock;
100 }
101
102 ret = wait_for_completion_timeout(x: &sysmon->comp,
103 timeout: msecs_to_jiffies(m: 5000));
104 if (!ret) {
105 dev_err(sysmon->dev, "timeout waiting for sysmon ack\n");
106 goto out_unlock;
107 }
108
109 if (!sysmon->ssr_ack)
110 dev_err(sysmon->dev, "unexpected response to sysmon event\n");
111
112out_unlock:
113 mutex_unlock(lock: &sysmon->lock);
114}
115
116/**
117 * sysmon_request_shutdown() - request graceful shutdown of remote
118 * @sysmon: sysmon context
119 *
120 * Return: boolean indicator of the remote processor acking the request
121 */
122static bool sysmon_request_shutdown(struct qcom_sysmon *sysmon)
123{
124 char *req = "ssr:shutdown";
125 bool acked = false;
126 int ret;
127
128 mutex_lock(&sysmon->lock);
129 reinit_completion(x: &sysmon->comp);
130 sysmon->ssr_ack = false;
131
132 ret = rpmsg_send(ept: sysmon->ept, data: req, strlen(req) + 1);
133 if (ret < 0) {
134 dev_err(sysmon->dev, "send sysmon shutdown request failed\n");
135 goto out_unlock;
136 }
137
138 ret = wait_for_completion_timeout(x: &sysmon->comp,
139 timeout: msecs_to_jiffies(m: 5000));
140 if (!ret) {
141 dev_err(sysmon->dev, "timeout waiting for sysmon ack\n");
142 goto out_unlock;
143 }
144
145 if (!sysmon->ssr_ack)
146 dev_err(sysmon->dev,
147 "unexpected response to sysmon shutdown request\n");
148 else
149 acked = true;
150
151out_unlock:
152 mutex_unlock(lock: &sysmon->lock);
153
154 return acked;
155}
156
157static int sysmon_callback(struct rpmsg_device *rpdev, void *data, int count,
158 void *priv, u32 addr)
159{
160 struct qcom_sysmon *sysmon = priv;
161 const char *ssr_ack = "ssr:ack";
162 const int ssr_ack_len = strlen(ssr_ack) + 1;
163
164 if (!sysmon)
165 return -EINVAL;
166
167 if (count >= ssr_ack_len && !memcmp(p: data, q: ssr_ack, size: ssr_ack_len))
168 sysmon->ssr_ack = true;
169
170 complete(&sysmon->comp);
171
172 return 0;
173}
174
175#define SSCTL_SHUTDOWN_REQ 0x21
176#define SSCTL_SHUTDOWN_READY_IND 0x21
177#define SSCTL_SUBSYS_EVENT_REQ 0x23
178
179#define SSCTL_MAX_MSG_LEN 7
180
181#define SSCTL_SUBSYS_NAME_LENGTH 15
182
183enum {
184 SSCTL_SSR_EVENT_FORCED,
185 SSCTL_SSR_EVENT_GRACEFUL,
186};
187
188struct ssctl_shutdown_resp {
189 struct qmi_response_type_v01 resp;
190};
191
192static const struct qmi_elem_info ssctl_shutdown_resp_ei[] = {
193 {
194 .data_type = QMI_STRUCT,
195 .elem_len = 1,
196 .elem_size = sizeof(struct qmi_response_type_v01),
197 .array_type = NO_ARRAY,
198 .tlv_type = 0x02,
199 .offset = offsetof(struct ssctl_shutdown_resp, resp),
200 .ei_array = qmi_response_type_v01_ei,
201 },
202 {}
203};
204
205struct ssctl_subsys_event_req {
206 u8 subsys_name_len;
207 char subsys_name[SSCTL_SUBSYS_NAME_LENGTH];
208 u32 event;
209 u8 evt_driven_valid;
210 u32 evt_driven;
211};
212
213static const struct qmi_elem_info ssctl_subsys_event_req_ei[] = {
214 {
215 .data_type = QMI_DATA_LEN,
216 .elem_len = 1,
217 .elem_size = sizeof(uint8_t),
218 .array_type = NO_ARRAY,
219 .tlv_type = 0x01,
220 .offset = offsetof(struct ssctl_subsys_event_req,
221 subsys_name_len),
222 .ei_array = NULL,
223 },
224 {
225 .data_type = QMI_UNSIGNED_1_BYTE,
226 .elem_len = SSCTL_SUBSYS_NAME_LENGTH,
227 .elem_size = sizeof(char),
228 .array_type = VAR_LEN_ARRAY,
229 .tlv_type = 0x01,
230 .offset = offsetof(struct ssctl_subsys_event_req,
231 subsys_name),
232 .ei_array = NULL,
233 },
234 {
235 .data_type = QMI_SIGNED_4_BYTE_ENUM,
236 .elem_len = 1,
237 .elem_size = sizeof(uint32_t),
238 .array_type = NO_ARRAY,
239 .tlv_type = 0x02,
240 .offset = offsetof(struct ssctl_subsys_event_req,
241 event),
242 .ei_array = NULL,
243 },
244 {
245 .data_type = QMI_OPT_FLAG,
246 .elem_len = 1,
247 .elem_size = sizeof(uint8_t),
248 .array_type = NO_ARRAY,
249 .tlv_type = 0x10,
250 .offset = offsetof(struct ssctl_subsys_event_req,
251 evt_driven_valid),
252 .ei_array = NULL,
253 },
254 {
255 .data_type = QMI_SIGNED_4_BYTE_ENUM,
256 .elem_len = 1,
257 .elem_size = sizeof(uint32_t),
258 .array_type = NO_ARRAY,
259 .tlv_type = 0x10,
260 .offset = offsetof(struct ssctl_subsys_event_req,
261 evt_driven),
262 .ei_array = NULL,
263 },
264 {}
265};
266
267struct ssctl_subsys_event_resp {
268 struct qmi_response_type_v01 resp;
269};
270
271static const struct qmi_elem_info ssctl_subsys_event_resp_ei[] = {
272 {
273 .data_type = QMI_STRUCT,
274 .elem_len = 1,
275 .elem_size = sizeof(struct qmi_response_type_v01),
276 .array_type = NO_ARRAY,
277 .tlv_type = 0x02,
278 .offset = offsetof(struct ssctl_subsys_event_resp,
279 resp),
280 .ei_array = qmi_response_type_v01_ei,
281 },
282 {}
283};
284
285static const struct qmi_elem_info ssctl_shutdown_ind_ei[] = {
286 {}
287};
288
289static void sysmon_ind_cb(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
290 struct qmi_txn *txn, const void *data)
291{
292 struct qcom_sysmon *sysmon = container_of(qmi, struct qcom_sysmon, qmi);
293
294 complete(&sysmon->ind_comp);
295}
296
297static const struct qmi_msg_handler qmi_indication_handler[] = {
298 {
299 .type = QMI_INDICATION,
300 .msg_id = SSCTL_SHUTDOWN_READY_IND,
301 .ei = ssctl_shutdown_ind_ei,
302 .decoded_size = 0,
303 .fn = sysmon_ind_cb
304 },
305 {}
306};
307
308static bool ssctl_request_shutdown_wait(struct qcom_sysmon *sysmon)
309{
310 int ret;
311
312 ret = wait_for_completion_timeout(x: &sysmon->shutdown_comp, timeout: 10 * HZ);
313 if (ret)
314 return true;
315
316 ret = try_wait_for_completion(x: &sysmon->ind_comp);
317 if (ret)
318 return true;
319
320 dev_err(sysmon->dev, "timeout waiting for shutdown ack\n");
321 return false;
322}
323
324/**
325 * ssctl_request_shutdown() - request shutdown via SSCTL QMI service
326 * @sysmon: sysmon context
327 *
328 * Return: boolean indicator of the remote processor acking the request
329 */
330static bool ssctl_request_shutdown(struct qcom_sysmon *sysmon)
331{
332 struct ssctl_shutdown_resp resp;
333 struct qmi_txn txn;
334 bool acked = false;
335 int ret;
336
337 reinit_completion(x: &sysmon->ind_comp);
338 reinit_completion(x: &sysmon->shutdown_comp);
339 ret = qmi_txn_init(qmi: &sysmon->qmi, txn: &txn, ei: ssctl_shutdown_resp_ei, c_struct: &resp);
340 if (ret < 0) {
341 dev_err(sysmon->dev, "failed to allocate QMI txn\n");
342 return false;
343 }
344
345 ret = qmi_send_request(qmi: &sysmon->qmi, sq: &sysmon->ssctl, txn: &txn,
346 SSCTL_SHUTDOWN_REQ, len: 0, NULL, NULL);
347 if (ret < 0) {
348 dev_err(sysmon->dev, "failed to send shutdown request\n");
349 qmi_txn_cancel(txn: &txn);
350 return false;
351 }
352
353 ret = qmi_txn_wait(txn: &txn, timeout: 5 * HZ);
354 if (ret < 0) {
355 dev_err(sysmon->dev, "timeout waiting for shutdown response\n");
356 } else if (resp.resp.result) {
357 dev_err(sysmon->dev, "shutdown request rejected\n");
358 } else {
359 dev_dbg(sysmon->dev, "shutdown request completed\n");
360 acked = true;
361 }
362
363 if (sysmon->shutdown_irq > 0)
364 return ssctl_request_shutdown_wait(sysmon);
365
366 return acked;
367}
368
369/**
370 * ssctl_send_event() - send notification of other remote's SSR event
371 * @sysmon: sysmon context
372 * @event: sysmon event context
373 */
374static void ssctl_send_event(struct qcom_sysmon *sysmon,
375 const struct sysmon_event *event)
376{
377 struct ssctl_subsys_event_resp resp;
378 struct ssctl_subsys_event_req req;
379 struct qmi_txn txn;
380 int ret;
381
382 memset(&resp, 0, sizeof(resp));
383 ret = qmi_txn_init(qmi: &sysmon->qmi, txn: &txn, ei: ssctl_subsys_event_resp_ei, c_struct: &resp);
384 if (ret < 0) {
385 dev_err(sysmon->dev, "failed to allocate QMI txn\n");
386 return;
387 }
388
389 memset(&req, 0, sizeof(req));
390 strscpy(p: req.subsys_name, q: event->subsys_name, size: sizeof(req.subsys_name));
391 req.subsys_name_len = strlen(req.subsys_name);
392 req.event = event->ssr_event;
393 req.evt_driven_valid = true;
394 req.evt_driven = SSCTL_SSR_EVENT_FORCED;
395
396 ret = qmi_send_request(qmi: &sysmon->qmi, sq: &sysmon->ssctl, txn: &txn,
397 SSCTL_SUBSYS_EVENT_REQ, len: 40,
398 ei: ssctl_subsys_event_req_ei, c_struct: &req);
399 if (ret < 0) {
400 dev_err(sysmon->dev, "failed to send subsystem event\n");
401 qmi_txn_cancel(txn: &txn);
402 return;
403 }
404
405 ret = qmi_txn_wait(txn: &txn, timeout: 5 * HZ);
406 if (ret < 0)
407 dev_err(sysmon->dev, "timeout waiting for subsystem event response\n");
408 else if (resp.resp.result)
409 dev_err(sysmon->dev, "subsystem event rejected\n");
410 else
411 dev_dbg(sysmon->dev, "subsystem event accepted\n");
412}
413
414/**
415 * ssctl_new_server() - QMI callback indicating a new service
416 * @qmi: QMI handle
417 * @svc: service information
418 *
419 * Return: 0 if we're interested in this service, -EINVAL otherwise.
420 */
421static int ssctl_new_server(struct qmi_handle *qmi, struct qmi_service *svc)
422{
423 struct qcom_sysmon *sysmon = container_of(qmi, struct qcom_sysmon, qmi);
424
425 switch (svc->version) {
426 case 1:
427 if (svc->instance != 0)
428 return -EINVAL;
429 if (strcmp(sysmon->name, "modem"))
430 return -EINVAL;
431 break;
432 case 2:
433 if (svc->instance != sysmon->ssctl_instance)
434 return -EINVAL;
435 break;
436 default:
437 return -EINVAL;
438 }
439
440 sysmon->ssctl_version = svc->version;
441
442 sysmon->ssctl.sq_family = AF_QIPCRTR;
443 sysmon->ssctl.sq_node = svc->node;
444 sysmon->ssctl.sq_port = svc->port;
445
446 svc->priv = sysmon;
447
448 complete(&sysmon->ssctl_comp);
449
450 return 0;
451}
452
453/**
454 * ssctl_del_server() - QMI callback indicating that @svc is removed
455 * @qmi: QMI handle
456 * @svc: service information
457 */
458static void ssctl_del_server(struct qmi_handle *qmi, struct qmi_service *svc)
459{
460 struct qcom_sysmon *sysmon = svc->priv;
461
462 sysmon->ssctl_version = 0;
463}
464
465static const struct qmi_ops ssctl_ops = {
466 .new_server = ssctl_new_server,
467 .del_server = ssctl_del_server,
468};
469
470static int sysmon_prepare(struct rproc_subdev *subdev)
471{
472 struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon,
473 subdev);
474 struct sysmon_event event = {
475 .subsys_name = sysmon->name,
476 .ssr_event = SSCTL_SSR_EVENT_BEFORE_POWERUP
477 };
478
479 mutex_lock(&sysmon->state_lock);
480 sysmon->state = SSCTL_SSR_EVENT_BEFORE_POWERUP;
481 blocking_notifier_call_chain(nh: &sysmon_notifiers, val: 0, v: (void *)&event);
482 mutex_unlock(lock: &sysmon->state_lock);
483
484 return 0;
485}
486
487/**
488 * sysmon_start() - start callback for the sysmon remoteproc subdevice
489 * @subdev: instance of the sysmon subdevice
490 *
491 * Inform all the listners of sysmon notifications that the rproc associated
492 * to @subdev has booted up. The rproc that booted up also needs to know
493 * which rprocs are already up and running, so send start notifications
494 * on behalf of all the online rprocs.
495 */
496static int sysmon_start(struct rproc_subdev *subdev)
497{
498 struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon,
499 subdev);
500 struct qcom_sysmon *target;
501 struct sysmon_event event = {
502 .subsys_name = sysmon->name,
503 .ssr_event = SSCTL_SSR_EVENT_AFTER_POWERUP
504 };
505
506 reinit_completion(x: &sysmon->ssctl_comp);
507 mutex_lock(&sysmon->state_lock);
508 sysmon->state = SSCTL_SSR_EVENT_AFTER_POWERUP;
509 blocking_notifier_call_chain(nh: &sysmon_notifiers, val: 0, v: (void *)&event);
510 mutex_unlock(lock: &sysmon->state_lock);
511
512 mutex_lock(&sysmon_lock);
513 list_for_each_entry(target, &sysmon_list, node) {
514 mutex_lock(&target->state_lock);
515 if (target == sysmon || target->state != SSCTL_SSR_EVENT_AFTER_POWERUP) {
516 mutex_unlock(lock: &target->state_lock);
517 continue;
518 }
519
520 event.subsys_name = target->name;
521 event.ssr_event = target->state;
522
523 if (sysmon->ssctl_version == 2)
524 ssctl_send_event(sysmon, event: &event);
525 else if (sysmon->ept)
526 sysmon_send_event(sysmon, event: &event);
527 mutex_unlock(lock: &target->state_lock);
528 }
529 mutex_unlock(lock: &sysmon_lock);
530
531 return 0;
532}
533
534static void sysmon_stop(struct rproc_subdev *subdev, bool crashed)
535{
536 struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon, subdev);
537 struct sysmon_event event = {
538 .subsys_name = sysmon->name,
539 .ssr_event = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN
540 };
541
542 sysmon->shutdown_acked = false;
543
544 mutex_lock(&sysmon->state_lock);
545 sysmon->state = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN;
546 blocking_notifier_call_chain(nh: &sysmon_notifiers, val: 0, v: (void *)&event);
547 mutex_unlock(lock: &sysmon->state_lock);
548
549 /* Don't request graceful shutdown if we've crashed */
550 if (crashed)
551 return;
552
553 if (sysmon->ssctl_instance) {
554 if (!wait_for_completion_timeout(x: &sysmon->ssctl_comp, HZ / 2))
555 dev_err(sysmon->dev, "timeout waiting for ssctl service\n");
556 }
557
558 if (sysmon->ssctl_version)
559 sysmon->shutdown_acked = ssctl_request_shutdown(sysmon);
560 else if (sysmon->ept)
561 sysmon->shutdown_acked = sysmon_request_shutdown(sysmon);
562}
563
564static void sysmon_unprepare(struct rproc_subdev *subdev)
565{
566 struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon,
567 subdev);
568 struct sysmon_event event = {
569 .subsys_name = sysmon->name,
570 .ssr_event = SSCTL_SSR_EVENT_AFTER_SHUTDOWN
571 };
572
573 mutex_lock(&sysmon->state_lock);
574 sysmon->state = SSCTL_SSR_EVENT_AFTER_SHUTDOWN;
575 blocking_notifier_call_chain(nh: &sysmon_notifiers, val: 0, v: (void *)&event);
576 mutex_unlock(lock: &sysmon->state_lock);
577}
578
579/**
580 * sysmon_notify() - notify sysmon target of another's SSR
581 * @nb: notifier_block associated with sysmon instance
582 * @event: unused
583 * @data: SSR identifier of the remote that is going down
584 */
585static int sysmon_notify(struct notifier_block *nb, unsigned long event,
586 void *data)
587{
588 struct qcom_sysmon *sysmon = container_of(nb, struct qcom_sysmon, nb);
589 struct sysmon_event *sysmon_event = data;
590
591 /* Skip non-running rprocs and the originating instance */
592 if (sysmon->state != SSCTL_SSR_EVENT_AFTER_POWERUP ||
593 !strcmp(sysmon_event->subsys_name, sysmon->name)) {
594 dev_dbg(sysmon->dev, "not notifying %s\n", sysmon->name);
595 return NOTIFY_DONE;
596 }
597
598 /* Only SSCTL version 2 supports SSR events */
599 if (sysmon->ssctl_version == 2)
600 ssctl_send_event(sysmon, event: sysmon_event);
601 else if (sysmon->ept)
602 sysmon_send_event(sysmon, event: sysmon_event);
603
604 return NOTIFY_DONE;
605}
606
607static irqreturn_t sysmon_shutdown_interrupt(int irq, void *data)
608{
609 struct qcom_sysmon *sysmon = data;
610
611 complete(&sysmon->shutdown_comp);
612
613 return IRQ_HANDLED;
614}
615
616/**
617 * qcom_add_sysmon_subdev() - create a sysmon subdev for the given remoteproc
618 * @rproc: rproc context to associate the subdev with
619 * @name: name of this subdev, to use in SSR
620 * @ssctl_instance: instance id of the ssctl QMI service
621 *
622 * Return: A new qcom_sysmon object, or NULL on failure
623 */
624struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
625 const char *name,
626 int ssctl_instance)
627{
628 struct qcom_sysmon *sysmon;
629 int ret;
630
631 sysmon = kzalloc(size: sizeof(*sysmon), GFP_KERNEL);
632 if (!sysmon)
633 return ERR_PTR(error: -ENOMEM);
634
635 sysmon->dev = rproc->dev.parent;
636 sysmon->rproc = rproc;
637
638 sysmon->name = name;
639 sysmon->ssctl_instance = ssctl_instance;
640
641 init_completion(x: &sysmon->comp);
642 init_completion(x: &sysmon->ind_comp);
643 init_completion(x: &sysmon->shutdown_comp);
644 init_completion(x: &sysmon->ssctl_comp);
645 mutex_init(&sysmon->lock);
646 mutex_init(&sysmon->state_lock);
647
648 sysmon->shutdown_irq = of_irq_get_byname(dev: sysmon->dev->of_node,
649 name: "shutdown-ack");
650 if (sysmon->shutdown_irq < 0) {
651 if (sysmon->shutdown_irq != -ENODATA) {
652 dev_err(sysmon->dev,
653 "failed to retrieve shutdown-ack IRQ\n");
654 ret = sysmon->shutdown_irq;
655 kfree(objp: sysmon);
656 return ERR_PTR(error: ret);
657 }
658 } else {
659 ret = devm_request_threaded_irq(dev: sysmon->dev,
660 irq: sysmon->shutdown_irq,
661 NULL, thread_fn: sysmon_shutdown_interrupt,
662 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
663 devname: "q6v5 shutdown-ack", dev_id: sysmon);
664 if (ret) {
665 dev_err(sysmon->dev,
666 "failed to acquire shutdown-ack IRQ\n");
667 kfree(objp: sysmon);
668 return ERR_PTR(error: ret);
669 }
670 }
671
672 ret = qmi_handle_init(qmi: &sysmon->qmi, SSCTL_MAX_MSG_LEN, ops: &ssctl_ops,
673 handlers: qmi_indication_handler);
674 if (ret < 0) {
675 dev_err(sysmon->dev, "failed to initialize qmi handle\n");
676 kfree(objp: sysmon);
677 return ERR_PTR(error: ret);
678 }
679
680 qmi_add_lookup(qmi: &sysmon->qmi, service: 43, version: 0, instance: 0);
681
682 sysmon->subdev.prepare = sysmon_prepare;
683 sysmon->subdev.start = sysmon_start;
684 sysmon->subdev.stop = sysmon_stop;
685 sysmon->subdev.unprepare = sysmon_unprepare;
686
687 rproc_add_subdev(rproc, subdev: &sysmon->subdev);
688
689 sysmon->nb.notifier_call = sysmon_notify;
690 blocking_notifier_chain_register(nh: &sysmon_notifiers, nb: &sysmon->nb);
691
692 mutex_lock(&sysmon_lock);
693 list_add(new: &sysmon->node, head: &sysmon_list);
694 mutex_unlock(lock: &sysmon_lock);
695
696 return sysmon;
697}
698EXPORT_SYMBOL_GPL(qcom_add_sysmon_subdev);
699
700/**
701 * qcom_remove_sysmon_subdev() - release a qcom_sysmon
702 * @sysmon: sysmon context, as retrieved by qcom_add_sysmon_subdev()
703 */
704void qcom_remove_sysmon_subdev(struct qcom_sysmon *sysmon)
705{
706 if (!sysmon)
707 return;
708
709 mutex_lock(&sysmon_lock);
710 list_del(entry: &sysmon->node);
711 mutex_unlock(lock: &sysmon_lock);
712
713 blocking_notifier_chain_unregister(nh: &sysmon_notifiers, nb: &sysmon->nb);
714
715 rproc_remove_subdev(rproc: sysmon->rproc, subdev: &sysmon->subdev);
716
717 qmi_handle_release(qmi: &sysmon->qmi);
718
719 kfree(objp: sysmon);
720}
721EXPORT_SYMBOL_GPL(qcom_remove_sysmon_subdev);
722
723/**
724 * qcom_sysmon_shutdown_acked() - query the success of the last shutdown
725 * @sysmon: sysmon context
726 *
727 * When sysmon is used to request a graceful shutdown of the remote processor
728 * this can be used by the remoteproc driver to query the success, in order to
729 * know if it should fall back to other means of requesting a shutdown.
730 *
731 * Return: boolean indicator of the success of the last shutdown request
732 */
733bool qcom_sysmon_shutdown_acked(struct qcom_sysmon *sysmon)
734{
735 return sysmon && sysmon->shutdown_acked;
736}
737EXPORT_SYMBOL_GPL(qcom_sysmon_shutdown_acked);
738
739/**
740 * sysmon_probe() - probe sys_mon channel
741 * @rpdev: rpmsg device handle
742 *
743 * Find the sysmon context associated with the ancestor remoteproc and assign
744 * this rpmsg device with said sysmon context.
745 *
746 * Return: 0 on success, negative errno on failure.
747 */
748static int sysmon_probe(struct rpmsg_device *rpdev)
749{
750 struct qcom_sysmon *sysmon;
751 struct rproc *rproc;
752
753 rproc = rproc_get_by_child(dev: &rpdev->dev);
754 if (!rproc) {
755 dev_err(&rpdev->dev, "sysmon device not child of rproc\n");
756 return -EINVAL;
757 }
758
759 mutex_lock(&sysmon_lock);
760 list_for_each_entry(sysmon, &sysmon_list, node) {
761 if (sysmon->rproc == rproc)
762 goto found;
763 }
764 mutex_unlock(lock: &sysmon_lock);
765
766 dev_err(&rpdev->dev, "no sysmon associated with parent rproc\n");
767
768 return -EINVAL;
769
770found:
771 mutex_unlock(lock: &sysmon_lock);
772
773 rpdev->ept->priv = sysmon;
774 sysmon->ept = rpdev->ept;
775
776 return 0;
777}
778
779/**
780 * sysmon_remove() - sys_mon channel remove handler
781 * @rpdev: rpmsg device handle
782 *
783 * Disassociate the rpmsg device with the sysmon instance.
784 */
785static void sysmon_remove(struct rpmsg_device *rpdev)
786{
787 struct qcom_sysmon *sysmon = rpdev->ept->priv;
788
789 sysmon->ept = NULL;
790}
791
792static const struct rpmsg_device_id sysmon_match[] = {
793 { "sys_mon" },
794 {}
795};
796
797static struct rpmsg_driver sysmon_driver = {
798 .probe = sysmon_probe,
799 .remove = sysmon_remove,
800 .callback = sysmon_callback,
801 .id_table = sysmon_match,
802 .drv = {
803 .name = "qcom_sysmon",
804 },
805};
806
807module_rpmsg_driver(sysmon_driver);
808
809MODULE_DESCRIPTION("Qualcomm sysmon driver");
810MODULE_LICENSE("GPL v2");
811

source code of linux/drivers/remoteproc/qcom_sysmon.c