summaryrefslogtreecommitdiffstats
path: root/drivers/soc/qcom/apr.c
blob: 1f35b097c6356bcd6c221d0d6d40ebed5ca2922b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2011-2017, The Linux Foundation. All rights reserved.
// Copyright (c) 2018, Linaro Limited

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/spinlock.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/of_device.h>
#include <linux/soc/qcom/apr.h>
#include <linux/soc/qcom/pdr.h>
#include <linux/rpmsg.h>
#include <linux/of.h>

struct apr {
	struct rpmsg_endpoint *ch;
	struct device *dev;
	spinlock_t svcs_lock;
	spinlock_t rx_lock;
	struct idr svcs_idr;
	int dest_domain_id;
	struct pdr_handle *pdr;
	struct workqueue_struct *rxwq;
	struct work_struct rx_work;
	struct list_head rx_list;
};

struct apr_rx_buf {
	struct list_head node;
	int len;
	uint8_t buf[];
};

/**
 * apr_send_pkt() - Send a apr message from apr device
 *
 * @adev: Pointer to previously registered apr device.
 * @pkt: Pointer to apr packet to send
 *
 * Return: Will be an negative on packet size on success.
 */
int apr_send_pkt(struct apr_device *adev, struct apr_pkt *pkt)
{
	struct apr *apr = dev_get_drvdata(adev->dev.parent);
	struct apr_hdr *hdr;
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&adev->lock, flags);

	hdr = &pkt->hdr;
	hdr->src_domain = APR_DOMAIN_APPS;
	hdr->src_svc = adev->svc_id;
	hdr->dest_domain = adev->domain_id;
	hdr->dest_svc = adev->svc_id;

	ret = rpmsg_trysend(apr->ch, pkt, hdr->pkt_size);
	spin_unlock_irqrestore(&adev->lock, flags);

	return ret ? ret : hdr->pkt_size;
}
EXPORT_SYMBOL_GPL(apr_send_pkt);

static void apr_dev_release(struct device *dev)
{
	struct apr_device *adev = to_apr_device(dev);

	kfree(adev);
}

static int apr_callback(struct rpmsg_device *rpdev, void *buf,
				  int len, void *priv, u32 addr)
{
	struct apr *apr = dev_get_drvdata(&rpdev->dev);
	struct apr_rx_buf *abuf;
	unsigned long flags;

	if (len <= APR_HDR_SIZE) {
		dev_err(apr->dev, "APR: Improper apr pkt received:%p %d\n",
			buf, len);
		return -EINVAL;
	}

	abuf = kzalloc(sizeof(*abuf) + len, GFP_ATOMIC);
	if (!abuf)
		return -ENOMEM;

	abuf->len = len;
	memcpy(abuf->buf, buf, len);

	spin_lock_irqsave(&apr->rx_lock, flags);
	list_add_tail(&abuf->node, &apr->rx_list);
	spin_unlock_irqrestore(&apr->rx_lock, flags);

	queue_work(apr->rxwq, &apr->rx_work);

	return 0;
}


static int apr_do_rx_callback(struct apr *apr, struct apr_rx_buf *abuf)
{
	uint16_t hdr_size, msg_type, ver, svc_id;
	struct apr_device *svc = NULL;
	struct apr_driver *adrv = NULL;
	struct apr_resp_pkt resp;
	struct apr_hdr *hdr;
	unsigned long flags;
	void *buf = abuf->buf;
	int len = abuf->len;

	hdr = buf;
	ver = APR_HDR_FIELD_VER(hdr->hdr_field);
	if (ver > APR_PKT_VER + 1)
		return -EINVAL;

	hdr_size = APR_HDR_FIELD_SIZE_BYTES(hdr->hdr_field);
	if (hdr_size < APR_HDR_SIZE) {
		dev_err(apr->dev, "APR: Wrong hdr size:%d\n", hdr_size);
		return -EINVAL;
	}

	if (hdr->pkt_size < APR_HDR_SIZE || hdr->pkt_size != len) {
		dev_err(apr->dev, "APR: Wrong packet size\n");
		return -EINVAL;
	}

	msg_type = APR_HDR_FIELD_MT(hdr->hdr_field);
	if (msg_type >= APR_MSG_TYPE_MAX) {
		dev_err(apr->dev, "APR: Wrong message type: %d\n", msg_type);
		return -EINVAL;
	}

	if (hdr->src_domain >= APR_DOMAIN_MAX ||
			hdr->dest_domain >= APR_DOMAIN_MAX ||
			hdr->src_svc >= APR_SVC_MAX ||
			hdr->dest_svc >= APR_SVC_MAX) {
		dev_err(apr->dev, "APR: Wrong APR header\n");
		return -EINVAL;
	}

	svc_id = hdr->dest_svc;
	spin_lock_irqsave(&apr->svcs_lock, flags);
	svc = idr_find(&apr->svcs_idr, svc_id);
	if (svc && svc->dev.driver)
		adrv = to_apr_driver(svc->dev.driver);
	spin_unlock_irqrestore(&apr->svcs_lock, flags);

	if (!adrv) {
		dev_err(apr->dev, "APR: service is not registered\n");
		return -EINVAL;
	}

	resp.hdr = *hdr;
	resp.payload_size = hdr->pkt_size - hdr_size;

	/*
	 * NOTE: hdr_size is not same as APR_HDR_SIZE as remote can include
	 * optional headers in to apr_hdr which should be ignored
	 */
	if (resp.payload_size > 0)
		resp.payload = buf + hdr_size;

	adrv->callback(svc, &resp);

	return 0;
}

static void apr_rxwq(struct work_struct *work)
{
	struct apr *apr = container_of(work, struct apr, rx_work);
	struct apr_rx_buf *abuf, *b;
	unsigned long flags;

	if (!list_empty(&apr->rx_list)) {
		list_for_each_entry_safe(abuf, b, &apr->rx_list, node) {
			apr_do_rx_callback(apr, abuf);
			spin_lock_irqsave(&apr->rx_lock, flags);
			list_del(&abuf->node);
			spin_unlock_irqrestore(&apr->rx_lock, flags);
			kfree(abuf);
		}
	}
}

static int apr_device_match(struct device *dev, struct device_driver *drv)
{
	struct apr_device *adev = to_apr_device(dev);
	struct apr_driver *adrv = to_apr_driver(drv);
	const struct apr_device_id *id = adrv->id_table;

	/* Attempt an OF style match first */
	if (of_driver_match_device(dev, drv))
		return 1;

	if (!id)
		return 0;

	while (id->domain_id != 0 || id->svc_id != 0) {
		if (id->domain_id == adev->domain_id &&
		    id->svc_id == adev->svc_id)
			return 1;
		id++;
	}

	return 0;
}

static int apr_device_probe(struct device *dev)
{
	struct apr_device *adev = to_apr_device(dev);
	struct apr_driver *adrv = to_apr_driver(dev->driver);

	return adrv->probe(adev);
}

static int apr_device_remove(struct device *dev)
{
	struct apr_device *adev = to_apr_device(dev);
	struct apr_driver *adrv;
	struct apr *apr = dev_get_drvdata(adev->dev.parent);

	if (dev->driver) {
		adrv = to_apr_driver(dev->driver);
		if (adrv->remove)
			adrv->remove(adev);
		spin_lock(&apr->svcs_lock);
		idr_remove(&apr->svcs_idr, adev->svc_id);
		spin_unlock(&apr->svcs_lock);
	}

	return 0;
}

static int apr_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct apr_device *adev = to_apr_device(dev);
	int ret;

	ret = of_device_uevent_modalias(dev, env);
	if (ret != -ENODEV)
		return ret;

	return add_uevent_var(env, "MODALIAS=apr:%s", adev->name);
}

struct bus_type aprbus = {
	.name		= "aprbus",
	.match		= apr_device_match,
	.probe		= apr_device_probe,
	.uevent		= apr_uevent,
	.remove		= apr_device_remove,
};
EXPORT_SYMBOL_GPL(aprbus);

static int apr_add_device(struct device *dev, struct device_node *np,
			  const struct apr_device_id *id)
{
	struct apr *apr = dev_get_drvdata(dev);
	struct apr_device *adev = NULL;
	int ret;

	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
	if (!adev)
		return -ENOMEM;

	spin_lock_init(&adev->lock);

	adev->svc_id = id->svc_id;
	adev->domain_id = id->domain_id;
	adev->version = id->svc_version;
	if (np)
		snprintf(adev->name, APR_NAME_SIZE, "%pOFn", np);
	else
		strscpy(adev->name, id->name, APR_NAME_SIZE);

	dev_set_name(&adev->dev, "aprsvc:%s:%x:%x", adev->name,
		     id->domain_id, id->svc_id);

	adev->dev.bus = &aprbus;
	adev->dev.parent = dev;
	adev->dev.of_node = np;
	adev->dev.release = apr_dev_release;
	adev->dev.driver = NULL;

	spin_lock(&apr->svcs_lock);
	idr_alloc(&apr->svcs_idr, adev, id->svc_id,
		  id->svc_id + 1, GFP_ATOMIC);
	spin_unlock(&apr->svcs_lock);

	of_property_read_string_index(np, "qcom,protection-domain",
				      1, &adev->service_path);

	dev_info(dev, "Adding APR dev: %s\n", dev_name(&adev->dev));

	ret = device_register(&adev->dev);
	if (ret) {
		dev_err(dev, "device_register failed: %d\n", ret);
		put_device(&adev->dev);
	}

	return ret;
}

static int of_apr_add_pd_lookups(struct device *dev)
{
	const char *service_name, *service_path;
	struct apr *apr = dev_get_drvdata(dev);
	struct device_node *node;
	struct pdr_service *pds;
	int ret;

	for_each_child_of_node(dev->of_node, node) {
		ret = of_property_read_string_index(node, "qcom,protection-domain",
						    0, &service_name);
		if (ret < 0)
			continue;

		ret = of_property_read_string_index(node, "qcom,protection-domain",
						    1, &service_path);
		if (ret < 0) {
			dev_err(dev, "pdr service path missing: %d\n", ret);
			return ret;
		}

		pds = pdr_add_lookup(apr->pdr, service_name, service_path);
		if (IS_ERR(pds) && PTR_ERR(pds) != -EALREADY) {
			dev_err(dev, "pdr add lookup failed: %d\n", ret);
			return PTR_ERR(pds);
		}
	}

	return 0;
}

static void of_register_apr_devices(struct device *dev, const char *svc_path)
{
	struct apr *apr = dev_get_drvdata(dev);
	struct device_node *node;
	const char *service_path;
	int ret;

	for_each_child_of_node(dev->of_node, node) {
		struct apr_device_id id = { {0} };

		/*
		 * This function is called with svc_path NULL during
		 * apr_probe(), in which case we register any apr devices
		 * without a qcom,protection-domain specified.
		 *
		 * Then as the protection domains becomes available
		 * (if applicable) this function is again called, but with
		 * svc_path representing the service becoming available. In
		 * this case we register any apr devices with a matching
		 * qcom,protection-domain.
		 */

		ret = of_property_read_string_index(node, "qcom,protection-domain",
						    1, &service_path);
		if (svc_path) {
			/* skip APR services that are PD independent */
			if (ret)
				continue;

			/* skip APR services whose PD paths don't match */
			if (strcmp(service_path, svc_path))
				continue;
		} else {
			/* skip APR services whose PD lookups are registered */
			if (ret == 0)
				continue;
		}

		if (of_property_read_u32(node, "reg", &id.svc_id))
			continue;

		id.domain_id = apr->dest_domain_id;

		if (apr_add_device(dev, node, &id))
			dev_err(dev, "Failed to add apr %d svc\n", id.svc_id);
	}
}

static int apr_remove_device(struct device *dev, void *svc_path)
{
	struct apr_device *adev = to_apr_device(dev);

	if (svc_path && adev->service_path) {
		if (!strcmp(adev->service_path, (char *)svc_path))
			device_unregister(&adev->dev);
	} else {
		device_unregister(&adev->dev);
	}

	return 0;
}

static void apr_pd_status(int state, char *svc_path, void *priv)
{
	struct apr *apr = (struct apr *)priv;

	switch (state) {
	case SERVREG_SERVICE_STATE_UP:
		of_register_apr_devices(apr->dev, svc_path);
		break;
	case SERVREG_SERVICE_STATE_DOWN:
		device_for_each_child(apr->dev, svc_path, apr_remove_device);
		break;
	}
}

static int apr_probe(struct rpmsg_device *rpdev)
{
	struct device *dev = &rpdev->dev;
	struct apr *apr;
	int ret;

	apr = devm_kzalloc(dev, sizeof(*apr), GFP_KERNEL);
	if (!apr)
		return -ENOMEM;

	ret = of_property_read_u32(dev->of_node, "qcom,apr-domain", &apr->dest_domain_id);
	if (ret) {
		dev_err(dev, "APR Domain ID not specified in DT\n");
		return ret;
	}

	dev_set_drvdata(dev, apr);
	apr->ch = rpdev->ept;
	apr->dev = dev;
	apr->rxwq = create_singlethread_workqueue("qcom_apr_rx");
	if (!apr->rxwq) {
		dev_err(apr->dev, "Failed to start Rx WQ\n");
		return -ENOMEM;
	}
	INIT_WORK(&apr->rx_work, apr_rxwq);

	apr->pdr = pdr_handle_alloc(apr_pd_status, apr);
	if (IS_ERR(apr->pdr)) {
		dev_err(dev, "Failed to init PDR handle\n");
		ret = PTR_ERR(apr->pdr);
		goto destroy_wq;
	}

	INIT_LIST_HEAD(&apr->rx_list);
	spin_lock_init(&apr->rx_lock);
	spin_lock_init(&apr->svcs_lock);
	idr_init(&apr->svcs_idr);

	ret = of_apr_add_pd_lookups(dev);
	if (ret)
		goto handle_release;

	of_register_apr_devices(dev, NULL);

	return 0;

handle_release:
	pdr_handle_release(apr->pdr);
destroy_wq:
	destroy_workqueue(apr->rxwq);
	return ret;
}

static void apr_remove(struct rpmsg_device *rpdev)
{
	struct apr *apr = dev_get_drvdata(&rpdev->dev);

	pdr_handle_release(apr->pdr);
	device_for_each_child(&rpdev->dev, NULL, apr_remove_device);
	flush_workqueue(apr->rxwq);
	destroy_workqueue(apr->rxwq);
}

/*
 * __apr_driver_register() - Client driver registration with aprbus
 *
 * @drv:Client driver to be associated with client-device.
 * @owner: owning module/driver
 *
 * This API will register the client driver with the aprbus
 * It is called from the driver's module-init function.
 */
int __apr_driver_register(struct apr_driver *drv, struct module *owner)
{
	drv->driver.bus = &aprbus;
	drv->driver.owner = owner;

	return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(__apr_driver_register);

/*
 * apr_driver_unregister() - Undo effect of apr_driver_register
 *
 * @drv: Client driver to be unregistered
 */
void apr_driver_unregister(struct apr_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(apr_driver_unregister);

static const struct of_device_id apr_of_match[] = {
	{ .compatible = "qcom,apr"},
	{ .compatible = "qcom,apr-v2"},
	{}
};
MODULE_DEVICE_TABLE(of, apr_of_match);

static struct rpmsg_driver apr_driver = {
	.probe = apr_probe,
	.remove = apr_remove,
	.callback = apr_callback,
	.drv = {
		.name = "qcom,apr",
		.of_match_table = apr_of_match,
	},
};

static int __init apr_init(void)
{
	int ret;

	ret = bus_register(&aprbus);
	if (!ret)
		ret = register_rpmsg_driver(&apr_driver);
	else
		bus_unregister(&aprbus);

	return ret;
}

static void __exit apr_exit(void)
{
	bus_unregister(&aprbus);
	unregister_rpmsg_driver(&apr_driver);
}

subsys_initcall(apr_init);
module_exit(apr_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Qualcomm APR Bus");