xref: /netbsd-src/sys/external/bsd/vchiq/dist/interface/vchiq_arm/vchiq_arm.c (revision a7b0ae37b099612d38a9546d32c0cb0bcc029251)
1 /**
2  * Copyright (c) 2014 Raspberry Pi (Trading) Ltd. All rights reserved.
3  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions, and the following disclaimer,
10  *    without modification.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The names of the above-listed copyright holders may not be used
15  *    to endorse or promote products derived from this software without
16  *    specific prior written permission.
17  *
18  * ALTERNATIVELY, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2, as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
23  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
26  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
29  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #include <sys/systm.h>
37 #include <sys/device.h>
38 #include <sys/file.h>
39 #include <sys/filedesc.h>
40 #include <sys/kmem.h>
41 
42 #include "vchiq_core.h"
43 #include "vchiq_ioctl.h"
44 #include "vchiq_arm.h"
45 #include "vchiq_debugfs.h"
46 
47 #define DEVICE_NAME "vchiq"
48 
49 /* Override the default prefix, which would be vchiq_arm (from the filename) */
50 #undef MODULE_PARAM_PREFIX
51 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
52 
53 #define VCHIQ_MINOR 0
54 
55 /* Some per-instance constants */
56 #define MAX_COMPLETIONS 128
57 #define MAX_SERVICES 64
58 #define MAX_ELEMENTS 8
59 #define MSG_QUEUE_SIZE 128
60 
61 #define KEEPALIVE_VER 1
62 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
63 
64 MALLOC_DEFINE(M_VCHIQ, "vchiq_cdev", "VideoCore cdev memory");
65 
66 /* Run time control of log level, based on KERN_XXX level. */
67 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
68 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
69 
70 #define SUSPEND_TIMER_TIMEOUT_MS 100
71 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
72 
73 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
74 static const char *const suspend_state_names[] = {
75 	"VC_SUSPEND_FORCE_CANCELED",
76 	"VC_SUSPEND_REJECTED",
77 	"VC_SUSPEND_FAILED",
78 	"VC_SUSPEND_IDLE",
79 	"VC_SUSPEND_REQUESTED",
80 	"VC_SUSPEND_IN_PROGRESS",
81 	"VC_SUSPEND_SUSPENDED"
82 };
83 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
84 static const char *const resume_state_names[] = {
85 	"VC_RESUME_FAILED",
86 	"VC_RESUME_IDLE",
87 	"VC_RESUME_REQUESTED",
88 	"VC_RESUME_IN_PROGRESS",
89 	"VC_RESUME_RESUMED"
90 };
91 /* The number of times we allow force suspend to timeout before actually
92 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
93 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
94 */
95 #define FORCE_SUSPEND_FAIL_MAX 8
96 
97 /* The time in ms allowed for videocore to go idle when force suspend has been
98  * requested */
99 #define FORCE_SUSPEND_TIMEOUT_MS 200
100 
101 
102 static void suspend_timer_callback(unsigned long context);
103 
104 
105 typedef struct user_service_struct {
106 	VCHIQ_SERVICE_T *service;
107 	void *userdata;
108 	VCHIQ_INSTANCE_T instance;
109 	char is_vchi;
110 	char dequeue_pending;
111 	char close_pending;
112 	int message_available_pos;
113 	int msg_insert;
114 	int msg_remove;
115 	struct semaphore insert_event;
116 	struct semaphore remove_event;
117 	struct semaphore close_event;
118 	VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
119 } USER_SERVICE_T;
120 
121 struct bulk_waiter_node {
122 	struct bulk_waiter bulk_waiter;
123 	int pid;
124 	struct list_head list;
125 };
126 
127 struct vchiq_instance_struct {
128 	VCHIQ_STATE_T *state;
129 	VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
130 	int completion_insert;
131 	int completion_remove;
132 	struct semaphore insert_event;
133 	struct semaphore remove_event;
134 	struct mutex completion_mutex;
135 
136 	int connected;
137 	int closing;
138 	int pid;
139 	int mark;
140 	int use_close_delivered;
141 	int trace;
142 
143 	struct list_head bulk_waiter_list;
144 	struct mutex bulk_waiter_list_mutex;
145 
146 	VCHIQ_DEBUGFS_NODE_T debugfs_node;
147 };
148 
149 typedef struct dump_context_struct {
150 	char __user *buf;
151 	size_t actual;
152 	size_t space;
153 	loff_t offset;
154 } DUMP_CONTEXT_T;
155 
156 VCHIQ_STATE_T g_state;
157 static DEFINE_SPINLOCK(msg_queue_spinlock);
158 
159 static const char *const ioctl_names[] = {
160 	"CONNECT",
161 	"SHUTDOWN",
162 	"CREATE_SERVICE",
163 	"REMOVE_SERVICE",
164 	"QUEUE_MESSAGE",
165 	"QUEUE_BULK_TRANSMIT",
166 	"QUEUE_BULK_RECEIVE",
167 	"AWAIT_COMPLETION",
168 	"DEQUEUE_MESSAGE",
169 	"GET_CLIENT_ID",
170 	"GET_CONFIG",
171 	"CLOSE_SERVICE",
172 	"USE_SERVICE",
173 	"RELEASE_SERVICE",
174 	"SET_SERVICE_OPTION",
175 	"DUMP_PHYS_MEM",
176 	"LIB_VERSION",
177 	"CLOSE_DELIVERED"
178 };
179 
180 vchiq_static_assert((sizeof(ioctl_names)/sizeof(ioctl_names[0])) ==
181 	(VCHIQ_IOC_MAX + 1));
182 
183 static dev_type_open(vchiq_open);
184 
185 struct cdevsw vchiq_cdevsw = {
186 	.d_open = vchiq_open,
187 	.d_close = noclose,
188 	.d_read = noread,
189 	.d_write = nowrite,
190 	.d_ioctl = noioctl,
191 	.d_stop = nostop,
192 	.d_tty = notty,
193 	.d_poll = nopoll,
194 	.d_mmap = nommap,
195 	.d_kqfilter = nokqfilter,
196 	.d_discard = nodiscard,
197 	.d_flag = D_OTHER | D_MPSAFE
198 };
199 
200 extern struct cfdriver vchiq_cd;
201 
202 static int	vchiq_ioctl(struct file *, u_long, void *);
203 static int	vchiq_close(struct file *);
204 static int	vchiq_read(struct file *, off_t *, struct uio *, kauth_cred_t, int);
205 
206 static const struct fileops vchiq_fileops = {
207 	.fo_name = "vchiq",
208 	.fo_read = vchiq_read,
209 	.fo_write = fbadop_write,
210 	.fo_ioctl = vchiq_ioctl,
211 	.fo_fcntl = fnullop_fcntl,
212 	.fo_poll = fnullop_poll,
213 	.fo_stat = fbadop_stat,
214 	.fo_close = vchiq_close,
215 	.fo_kqfilter = fnullop_kqfilter,
216 };
217 
218 #if 0
219 static void
220 dump_phys_mem(void *virt_addr, uint32_t num_bytes);
221 #endif
222 
223 /****************************************************************************
224 *
225 *   add_completion
226 *
227 ***************************************************************************/
228 
229 static VCHIQ_STATUS_T
add_completion(VCHIQ_INSTANCE_T instance,VCHIQ_REASON_T reason,VCHIQ_HEADER_T * header,USER_SERVICE_T * user_service,void * bulk_userdata)230 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
231 	VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
232 	void *bulk_userdata)
233 {
234 	VCHIQ_COMPLETION_DATA_T *completion;
235 	int insert;
236 	DEBUG_INITIALISE(g_state.local)
237 
238 	insert = instance->completion_insert;
239 	while ((insert - instance->completion_remove) >= MAX_COMPLETIONS) {
240 		/* Out of space - wait for the client */
241 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
242 		vchiq_log_trace(vchiq_arm_log_level,
243 			"add_completion - completion queue full");
244 		DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
245 
246 		if (down_interruptible(&instance->remove_event) != 0) {
247 			vchiq_log_info(vchiq_arm_log_level,
248 				"service_callback interrupted");
249 			return VCHIQ_RETRY;
250 		}
251 
252 		if (instance->closing) {
253 			vchiq_log_info(vchiq_arm_log_level,
254 				"service_callback closing");
255 			return VCHIQ_SUCCESS;
256 		}
257 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
258 	}
259 
260 	completion = &instance->completions[insert & (MAX_COMPLETIONS - 1)];
261 
262 	completion->header = header;
263 	completion->reason = reason;
264 	/* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
265 	completion->service_userdata = user_service->service;
266 	completion->bulk_userdata = bulk_userdata;
267 
268 	if (reason == VCHIQ_SERVICE_CLOSED) {
269 		/* Take an extra reference, to be held until
270 		   this CLOSED notification is delivered. */
271 		lock_service(user_service->service);
272 		if (instance->use_close_delivered)
273 			user_service->close_pending = 1;
274 	}
275 
276 	/* A write barrier is needed here to ensure that the entire completion
277 		record is written out before the insert point. */
278 	wmb();
279 
280 	if (reason == VCHIQ_MESSAGE_AVAILABLE)
281 		user_service->message_available_pos = insert;
282 
283 	instance->completion_insert = ++insert;
284 
285 	up(&instance->insert_event);
286 
287 	return VCHIQ_SUCCESS;
288 }
289 
290 /****************************************************************************
291 *
292 *   service_callback
293 *
294 ***************************************************************************/
295 
296 static VCHIQ_STATUS_T
service_callback(VCHIQ_REASON_T reason,VCHIQ_HEADER_T * header,VCHIQ_SERVICE_HANDLE_T handle,void * bulk_userdata)297 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
298 	VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
299 {
300 	/* How do we ensure the callback goes to the right client?
301 	** The service_user data points to a USER_SERVICE_T record containing
302 	** the original callback and the user state structure, which contains a
303 	** circular buffer for completion records.
304 	*/
305 	USER_SERVICE_T *user_service;
306 	VCHIQ_SERVICE_T *service;
307 	VCHIQ_INSTANCE_T instance;
308 	int skip_completion = 0;
309 	DEBUG_INITIALISE(g_state.local)
310 
311 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
312 
313 	service = handle_to_service(handle);
314 	BUG_ON(!service);
315 	user_service = (USER_SERVICE_T *)service->base.userdata;
316 	instance = user_service->instance;
317 
318 	if (!instance || instance->closing)
319 		return VCHIQ_SUCCESS;
320 
321 	vchiq_log_trace(vchiq_arm_log_level,
322 		"service_callback - service %lx(%d,%p), reason %d, header %lx, "
323 		"instance %lx, bulk_userdata %lx",
324 		(unsigned long)user_service,
325 		service->localport, user_service->userdata,
326 		reason, (unsigned long)header,
327 		(unsigned long)instance, (unsigned long)bulk_userdata);
328 
329 	if (header && user_service->is_vchi) {
330 		spin_lock(&msg_queue_spinlock);
331 		while (user_service->msg_insert ==
332 			(user_service->msg_remove + MSG_QUEUE_SIZE)) {
333 			spin_unlock(&msg_queue_spinlock);
334 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
335 			DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
336 			vchiq_log_trace(vchiq_arm_log_level,
337 				"service_callback - msg queue full");
338 			/* If there is no MESSAGE_AVAILABLE in the completion
339 			** queue, add one
340 			*/
341 			if ((user_service->message_available_pos -
342 				instance->completion_remove) < 0) {
343 				VCHIQ_STATUS_T status;
344 				vchiq_log_info(vchiq_arm_log_level,
345 					"Inserting extra MESSAGE_AVAILABLE");
346 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
347 				status = add_completion(instance, reason,
348 					NULL, user_service, bulk_userdata);
349 				if (status != VCHIQ_SUCCESS) {
350 					DEBUG_TRACE(SERVICE_CALLBACK_LINE);
351 					return status;
352 				}
353 			}
354 
355 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
356 			if (down_interruptible(&user_service->remove_event)
357 				!= 0) {
358 				vchiq_log_info(vchiq_arm_log_level,
359 					"service_callback interrupted");
360 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
361 				return VCHIQ_RETRY;
362 			} else if (instance->closing) {
363 				vchiq_log_info(vchiq_arm_log_level,
364 					"service_callback closing");
365 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
366 				return VCHIQ_ERROR;
367 			}
368 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
369 			spin_lock(&msg_queue_spinlock);
370 		}
371 
372 		user_service->msg_queue[user_service->msg_insert &
373 			(MSG_QUEUE_SIZE - 1)] = header;
374 		user_service->msg_insert++;
375 
376 		/* If there is a thread waiting in DEQUEUE_MESSAGE, or if
377 		** there is a MESSAGE_AVAILABLE in the completion queue then
378 		** bypass the completion queue.
379 		*/
380 		if (((user_service->message_available_pos -
381 			instance->completion_remove) >= 0) ||
382 			user_service->dequeue_pending) {
383 			user_service->dequeue_pending = 0;
384 			skip_completion = 1;
385 		}
386 
387 		spin_unlock(&msg_queue_spinlock);
388 
389 		up(&user_service->insert_event);
390 
391 		header = NULL;
392 	}
393 
394 	if (skip_completion) {
395 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
396 		return VCHIQ_SUCCESS;
397 	}
398 
399 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
400 
401 	return add_completion(instance, reason, header, user_service,
402 		bulk_userdata);
403 }
404 
405 /****************************************************************************
406 *
407 *   user_service_free
408 *
409 ***************************************************************************/
410 static void
user_service_free(void * userdata)411 user_service_free(void *userdata)
412 {
413 	USER_SERVICE_T *user_service = userdata;
414 
415 	_sema_destroy(&user_service->insert_event);
416 	_sema_destroy(&user_service->remove_event);
417 
418 	kfree(user_service);
419 }
420 
421 /****************************************************************************
422 *
423 *   close_delivered
424 *
425 ***************************************************************************/
close_delivered(USER_SERVICE_T * user_service)426 static void close_delivered(USER_SERVICE_T *user_service)
427 {
428 	vchiq_log_info(vchiq_arm_log_level,
429 		"close_delivered(handle=%x)",
430 		user_service->service->handle);
431 
432 	if (user_service->close_pending) {
433 		/* Allow the underlying service to be culled */
434 		unlock_service(user_service->service);
435 
436 		/* Wake the user-thread blocked in close_ or remove_service */
437 		up(&user_service->close_event);
438 
439 		user_service->close_pending = 0;
440 	}
441 }
442 
443 /****************************************************************************
444 *
445 *   vchiq_ioctl
446 *
447 ***************************************************************************/
448 
449 static int
vchiq_ioctl(struct file * fp,u_long cmd,void * arg)450 vchiq_ioctl(struct file *fp, u_long cmd, void *arg)
451 {
452 	VCHIQ_INSTANCE_T instance = fp->f_data;
453 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
454 	VCHIQ_SERVICE_T *service = NULL;
455 	int ret = 0;
456 	int i, rc;
457 	DEBUG_INITIALISE(g_state.local)
458 
459 /* XXXBSD: HACK! */
460 #define _IOC_NR(x) ((x) & 0xff)
461 #define	_IOC_TYPE(x)	IOCGROUP(x)
462 
463 	vchiq_log_trace(vchiq_arm_log_level,
464 		 "vchiq_ioctl - instance %p, cmd %s, arg %p",
465 		instance,
466 		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
467 		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
468 		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
469 
470 	switch (cmd) {
471 	case VCHIQ_IOC_SHUTDOWN:
472 		if (!instance->connected)
473 			break;
474 
475 		/* Remove all services */
476 		i = 0;
477 		while ((service = next_service_by_instance(instance->state,
478 			instance, &i)) != NULL) {
479 			status = vchiq_remove_service(service->handle);
480 			unlock_service(service);
481 			if (status != VCHIQ_SUCCESS)
482 				break;
483 		}
484 		service = NULL;
485 
486 		if (status == VCHIQ_SUCCESS) {
487 			/* Wake the completion thread and ask it to exit */
488 			instance->closing = 1;
489 			up(&instance->insert_event);
490 		}
491 
492 		break;
493 
494 	case VCHIQ_IOC_CONNECT:
495 		if (instance->connected) {
496 			ret = -EINVAL;
497 			break;
498 		}
499 		rc = lmutex_lock_interruptible(&instance->state->mutex);
500 		if (rc != 0) {
501 			vchiq_log_error(vchiq_arm_log_level,
502 				"vchiq: connect: could not lock mutex for "
503 				"state %d: %d",
504 				instance->state->id, rc);
505 			ret = -EINTR;
506 			break;
507 		}
508 		status = vchiq_connect_internal(instance->state, instance);
509 		lmutex_unlock(&instance->state->mutex);
510 
511 		if (status == VCHIQ_SUCCESS)
512 			instance->connected = 1;
513 		else
514 			vchiq_log_error(vchiq_arm_log_level,
515 				"vchiq: could not connect: %d", status);
516 		break;
517 
518 	case VCHIQ_IOC_CREATE_SERVICE: {
519 		VCHIQ_CREATE_SERVICE_T *pargs = arg;
520 		VCHIQ_CREATE_SERVICE_T args = *pargs;
521 		USER_SERVICE_T *user_service = NULL;
522 		void *userdata;
523 		int srvstate;
524 
525 		/* XXXNH kmalloc */
526 		user_service = kzalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
527 		if (!user_service) {
528 			ret = -ENOMEM;
529 			break;
530 		}
531 
532 		if (args.is_open) {
533 			if (!instance->connected) {
534 				ret = -ENOTCONN;
535 				kfree(user_service);
536 				break;
537 			}
538 			srvstate = VCHIQ_SRVSTATE_OPENING;
539 		} else {
540 			srvstate =
541 				 instance->connected ?
542 				 VCHIQ_SRVSTATE_LISTENING :
543 				 VCHIQ_SRVSTATE_HIDDEN;
544 		}
545 
546 		userdata = args.params.userdata;
547 		pargs->params.callback = service_callback;
548 		pargs->params.userdata = user_service;
549 		args.params.callback = service_callback;
550 		args.params.userdata = user_service;
551 		service = vchiq_add_service_internal(
552 				instance->state,
553 				&pargs->params, srvstate,
554 				instance, user_service_free);
555 
556 		if (service != NULL) {
557 			user_service->service = service;
558 			user_service->userdata = userdata;
559 			user_service->instance = instance;
560 			user_service->is_vchi = (args.is_vchi != 0);
561 			user_service->dequeue_pending = 0;
562 			user_service->close_pending = 0;
563 			user_service->message_available_pos =
564 				instance->completion_remove - 1;
565 			user_service->msg_insert = 0;
566 			user_service->msg_remove = 0;
567 			_sema_init(&user_service->insert_event, 0);
568 			_sema_init(&user_service->remove_event, 0);
569 			_sema_init(&user_service->close_event, 0);
570 
571 			if (args.is_open) {
572 				status = vchiq_open_service_internal
573 					(service, instance->pid);
574 				if (status != VCHIQ_SUCCESS) {
575 					vchiq_remove_service(service->handle);
576 					service = NULL;
577 					ret = (status == VCHIQ_RETRY) ?
578 						-EINTR : -EIO;
579 					break;
580 				}
581 			}
582 
583 #ifdef VCHIQ_IOCTL_DEBUG
584 			printf("%s: [CREATE SERVICE] handle = %08x\n", __func__, service->handle);
585 #endif
586 			pargs->handle = service->handle;
587 
588 			service = NULL;
589 		} else {
590 			ret = -EEXIST;
591 			kfree(user_service);
592 		}
593 	} break;
594 
595 	case VCHIQ_IOC_CLOSE_SERVICE: {
596 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
597 
598 #ifdef VCHIQ_IOCTL_DEBUG
599 		printf("%s: [CLOSE SERVICE] handle = %08x\n", __func__, handle);
600 #endif
601 
602 		service = find_service_for_instance(instance, handle);
603 		if (service != NULL) {
604 			USER_SERVICE_T *user_service =
605 				(USER_SERVICE_T *)service->base.userdata;
606 			/* close_pending is false on first entry, and when the
607                            wait in vchiq_close_service has been interrupted. */
608 			if (!user_service->close_pending) {
609 				status = vchiq_close_service(service->handle);
610 				if (status != VCHIQ_SUCCESS)
611 					break;
612 			}
613 
614 			/* close_pending is true once the underlying service
615 			   has been closed until the client library calls the
616 			   CLOSE_DELIVERED ioctl, signalling close_event. */
617 			if (user_service->close_pending &&
618 				down_interruptible(&user_service->close_event))
619 				status = VCHIQ_RETRY;
620 		}
621 		else
622 			ret = -EINVAL;
623 	} break;
624 
625 	case VCHIQ_IOC_REMOVE_SERVICE: {
626 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
627 
628 #ifdef VCHIQ_IOCTL_DEBUG
629 		printf("%s: [REMOVE SERVICE] handle = %08x\n", __func__, handle);
630 #endif
631 
632 		service = find_service_for_instance(instance, handle);
633 		if (service != NULL) {
634 			USER_SERVICE_T *user_service =
635 				(USER_SERVICE_T *)service->base.userdata;
636 			/* close_pending is false on first entry, and when the
637                            wait in vchiq_close_service has been interrupted. */
638 			if (!user_service->close_pending) {
639 				status = vchiq_remove_service(service->handle);
640 				if (status != VCHIQ_SUCCESS)
641 					break;
642 			}
643 
644 			/* close_pending is true once the underlying service
645 			   has been closed until the client library calls the
646 			   CLOSE_DELIVERED ioctl, signalling close_event. */
647 			if (user_service->close_pending &&
648 				down_interruptible(&user_service->close_event))
649 				status = VCHIQ_RETRY;
650 		}
651 		else
652 			ret = -EINVAL;
653 	} break;
654 
655 	case VCHIQ_IOC_USE_SERVICE:
656 	case VCHIQ_IOC_RELEASE_SERVICE:	{
657 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
658 
659 #ifdef VCHIQ_IOCTL_DEBUG
660 		printf("%s: [%s SERVICE] handle = %08x\n", __func__,
661 		    cmd == VCHIQ_IOC_USE_SERVICE ? "USE" : "RELEASE", handle);
662 #endif
663 
664 		service = find_service_for_instance(instance, handle);
665 		if (service != NULL) {
666 			status = (cmd == VCHIQ_IOC_USE_SERVICE)	?
667 				vchiq_use_service_internal(service) :
668 				vchiq_release_service_internal(service);
669 			if (status != VCHIQ_SUCCESS) {
670 				vchiq_log_error(vchiq_susp_log_level,
671 					"%s: cmd %s returned error %d for "
672 					"service %c%c%c%c:%8x",
673 					__func__,
674 					(cmd == VCHIQ_IOC_USE_SERVICE) ?
675 						"VCHIQ_IOC_USE_SERVICE" :
676 						"VCHIQ_IOC_RELEASE_SERVICE",
677 					status,
678 					VCHIQ_FOURCC_AS_4CHARS(
679 						service->base.fourcc),
680 					service->client_id);
681 				ret = -EINVAL;
682 			}
683 		} else
684 			ret = -EINVAL;
685 	} break;
686 
687 	case VCHIQ_IOC_QUEUE_MESSAGE: {
688 		VCHIQ_QUEUE_MESSAGE_T *pargs = arg;
689 		VCHIQ_QUEUE_MESSAGE_T args = *pargs;
690 
691 #ifdef VCHIQ_IOCTL_DEBUG
692 		printf("%s: [QUEUE MESSAGE] handle = %08x\n", __func__, args.handle);
693 #endif
694 
695 		service = find_service_for_instance(instance, args.handle);
696 
697 		if ((service != NULL) && (args.count <= MAX_ELEMENTS)) {
698 			/* Copy elements into kernel space */
699 			VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
700 			if (copy_from_user(elements, args.elements,
701 				args.count * sizeof(VCHIQ_ELEMENT_T)) == 0)
702 				status = vchiq_queue_message
703 					(args.handle,
704 					elements, args.count);
705 			else
706 				ret = -EFAULT;
707 		} else {
708 			ret = -EINVAL;
709 		}
710 	} break;
711 
712 	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
713 	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
714 		VCHIQ_QUEUE_BULK_TRANSFER_T *pargs = arg;
715 		VCHIQ_QUEUE_BULK_TRANSFER_T args = *pargs;
716 		struct bulk_waiter_node *waiter = NULL;
717 		VCHIQ_BULK_DIR_T dir =
718 			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
719 			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
720 
721 		service = find_service_for_instance(instance, args.handle);
722 		if (!service) {
723 			ret = -EINVAL;
724 			break;
725 		}
726 
727 		if (args.mode == VCHIQ_BULK_MODE_BLOCKING) {
728 			waiter = kzalloc(sizeof(struct bulk_waiter_node),
729 				GFP_KERNEL);
730 			if (!waiter) {
731 				ret = -ENOMEM;
732 				break;
733 			}
734 			args.userdata = &waiter->bulk_waiter;
735 		} else if (args.mode == VCHIQ_BULK_MODE_WAITING) {
736 			struct list_head *pos;
737 			lmutex_lock(&instance->bulk_waiter_list_mutex);
738 			list_for_each(pos, &instance->bulk_waiter_list) {
739 				if (list_entry(pos, struct bulk_waiter_node,
740 					list)->pid == current->l_proc->p_pid) {
741 					waiter = list_entry(pos,
742 						struct bulk_waiter_node,
743 						list);
744 					list_del(pos);
745 					break;
746 				}
747 
748 			}
749 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
750 			if (!waiter) {
751 				vchiq_log_error(vchiq_arm_log_level,
752 					"no bulk_waiter found for pid %d",
753 					current->l_proc->p_pid);
754 				ret = -ESRCH;
755 				break;
756 			}
757 			vchiq_log_info(vchiq_arm_log_level,
758 				"found bulk_waiter %p for pid %d",
759 				waiter, current->l_proc->p_pid);
760 			args.userdata = &waiter->bulk_waiter;
761 		}
762 		status = vchiq_bulk_transfer
763 			(args.handle,
764 			 VCHI_MEM_HANDLE_INVALID,
765 			 args.data, args.size,
766 			 args.userdata, args.mode,
767 			 dir);
768 		if (!waiter)
769 			break;
770 		if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
771 			!waiter->bulk_waiter.bulk) {
772 			if (waiter->bulk_waiter.bulk) {
773 				/* Cancel the signal when the transfer
774 				** completes. */
775 				spin_lock(&bulk_waiter_spinlock);
776 				waiter->bulk_waiter.bulk->userdata = NULL;
777 				spin_unlock(&bulk_waiter_spinlock);
778 			}
779 			_sema_destroy(&waiter->bulk_waiter.event);
780 			kfree(waiter);
781 		} else {
782 			const VCHIQ_BULK_MODE_T mode_waiting =
783 				VCHIQ_BULK_MODE_WAITING;
784 			waiter->pid = current->l_proc->p_pid;
785 			lmutex_lock(&instance->bulk_waiter_list_mutex);
786 			list_add(&waiter->list, &instance->bulk_waiter_list);
787 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
788 			vchiq_log_info(vchiq_arm_log_level,
789 				"saved bulk_waiter %p for pid %d",
790 				waiter, current->l_proc->p_pid);
791 
792 			pargs->mode = mode_waiting;
793 		}
794 	} break;
795 
796 	case VCHIQ_IOC_AWAIT_COMPLETION: {
797 		VCHIQ_AWAIT_COMPLETION_T *pargs = arg;
798 		VCHIQ_AWAIT_COMPLETION_T args = *pargs;
799 		int count = 0;
800 
801 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
802 		if (!instance->connected) {
803 			ret = -ENOTCONN;
804 			break;
805 		}
806 
807 		lmutex_lock(&instance->completion_mutex);
808 
809 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
810 		while ((instance->completion_remove ==
811 			instance->completion_insert)
812 			&& !instance->closing) {
813 			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
814 			lmutex_unlock(&instance->completion_mutex);
815 			rc = down_interruptible(&instance->insert_event);
816 			lmutex_lock(&instance->completion_mutex);
817 			if (rc != 0) {
818 				DEBUG_TRACE(AWAIT_COMPLETION_LINE);
819 				vchiq_log_info(vchiq_arm_log_level,
820 					"AWAIT_COMPLETION interrupted");
821 				ret = -EINTR;
822 				break;
823 			}
824 		}
825 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
826 
827 		if (ret == 0) {
828 			int msgbufcount = args.msgbufcount;
829 			int remove;
830 
831 			remove = instance->completion_remove;
832 
833 			for (count = 0; count < args.count; count++) {
834 				VCHIQ_COMPLETION_DATA_T *completion;
835 				VCHIQ_SERVICE_T *service1;
836 				USER_SERVICE_T *user_service;
837 				VCHIQ_HEADER_T *header;
838 
839 				if (remove == instance->completion_insert)
840 					break;
841 
842 				completion = &instance->completions[
843 					remove & (MAX_COMPLETIONS - 1)];
844 
845 				/* A read memory barrier is needed to prevent
846 				** the prefetch of a stale completion record
847 				*/
848 				rmb();
849 
850 
851 				service1 = completion->service_userdata;
852 				user_service = service1->base.userdata;
853 				completion->service_userdata =
854 					user_service->userdata;
855 
856 				header = completion->header;
857 				if (header) {
858 					void __user *msgbuf;
859 					int msglen;
860 
861 					msglen = header->size +
862 						sizeof(VCHIQ_HEADER_T);
863 					/* This must be a VCHIQ-style service */
864 					if (args.msgbufsize < msglen) {
865 						vchiq_log_error(
866 							vchiq_arm_log_level,
867 							"header %p: msgbufsize"
868 							" %x < msglen %x",
869 							header,
870 							args.msgbufsize,
871 							msglen);
872 						WARN(1, "invalid message "
873 							"size\n");
874 						if (count == 0)
875 							ret = -EMSGSIZE;
876 						break;
877 					}
878 					if (msgbufcount <= 0)
879 						/* Stall here for lack of a
880 						** buffer for the message. */
881 						break;
882 					/* Get the pointer from user space */
883 					msgbufcount--;
884 					if (copy_from_user(&msgbuf,
885 						(const void __user *)
886 						&args.msgbufs[msgbufcount],
887 						sizeof(msgbuf)) != 0) {
888 						if (count == 0)
889 							ret = -EFAULT;
890 						break;
891 					}
892 
893 					/* Copy the message to user space */
894 					if (copy_to_user(msgbuf, header,
895 						msglen) != 0) {
896 						if (count == 0)
897 							ret = -EFAULT;
898 						break;
899 					}
900 
901 					/* Now it has been copied, the message
902 					** can be released. */
903 					vchiq_release_message(service1->handle,
904 						header);
905 
906 					/* The completion must point to the
907 					** msgbuf. */
908 					completion->header = msgbuf;
909 				}
910 
911 				if ((completion->reason ==
912 					VCHIQ_SERVICE_CLOSED) &&
913 					!instance->use_close_delivered)
914 					unlock_service(service1);
915 
916 				if (copy_to_user((void __user *)(
917 					(size_t)args.buf +
918 					count * sizeof(VCHIQ_COMPLETION_DATA_T)),
919 					completion,
920 					sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
921 						if (count == 0)
922 							ret = -EFAULT;
923 					break;
924 				}
925 
926 				/* Ensure that the above copy has completed
927 				** before advancing the remove pointer. */
928 				mb();
929 
930 				instance->completion_remove = ++remove;
931 			}
932 
933 			pargs->msgbufcount = msgbufcount;
934 			pargs->count = count;
935 		}
936 		if (count != 0)
937 			up(&instance->remove_event);
938 
939 		lmutex_unlock(&instance->completion_mutex);
940 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
941 	} break;
942 
943 	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
944 		VCHIQ_DEQUEUE_MESSAGE_T *pargs = arg;
945 		VCHIQ_DEQUEUE_MESSAGE_T args = *pargs;
946 		USER_SERVICE_T *user_service;
947 		VCHIQ_HEADER_T *header;
948 
949 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
950 		service = find_service_for_instance(instance, args.handle);
951 		if (!service) {
952 			ret = -EINVAL;
953 			break;
954 		}
955 		user_service = (USER_SERVICE_T *)service->base.userdata;
956 		if (user_service->is_vchi == 0) {
957 			ret = -EINVAL;
958 			break;
959 		}
960 
961 		spin_lock(&msg_queue_spinlock);
962 		if (user_service->msg_remove == user_service->msg_insert) {
963 			if (!args.blocking) {
964 				spin_unlock(&msg_queue_spinlock);
965 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
966 				ret = -EWOULDBLOCK;
967 				break;
968 			}
969 			user_service->dequeue_pending = 1;
970 			do {
971 				spin_unlock(&msg_queue_spinlock);
972 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
973 				if (down_interruptible(
974 					&user_service->insert_event) != 0) {
975 					vchiq_log_info(vchiq_arm_log_level,
976 						"DEQUEUE_MESSAGE interrupted");
977 					ret = -EINTR;
978 					break;
979 				}
980 				spin_lock(&msg_queue_spinlock);
981 			} while (user_service->msg_remove ==
982 				user_service->msg_insert);
983 
984 			if (ret)
985 				break;
986 		}
987 
988 		BUG_ON((int)(user_service->msg_insert -
989 			user_service->msg_remove) < 0);
990 
991 		header = user_service->msg_queue[user_service->msg_remove &
992 			(MSG_QUEUE_SIZE - 1)];
993 		user_service->msg_remove++;
994 		spin_unlock(&msg_queue_spinlock);
995 
996 		up(&user_service->remove_event);
997 		if (header == NULL)
998 			ret = -ENOTCONN;
999 		else if (header->size <= args.bufsize) {
1000 			/* Copy to user space if msgbuf is not NULL */
1001 			if ((args.buf == NULL) ||
1002 				(copy_to_user((void __user *)args.buf,
1003 				header->data,
1004 				header->size) == 0)) {
1005 				pargs->bufsize = header->size;
1006 				vchiq_release_message(
1007 					service->handle,
1008 					header);
1009 			} else
1010 				ret = -EFAULT;
1011 		} else {
1012 			vchiq_log_error(vchiq_arm_log_level,
1013 				"header %p: bufsize %x < size %x",
1014 				header, args.bufsize,
1015 				header->size);
1016 			WARN(1, "invalid size\n");
1017 			ret = -EMSGSIZE;
1018 		}
1019 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
1020 	} break;
1021 
1022 	case VCHIQ_IOC_GET_CLIENT_ID: {
1023 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
1024 
1025 		ret = vchiq_get_client_id(handle);
1026 	} break;
1027 
1028 	case VCHIQ_IOC_GET_CONFIG: {
1029 		VCHIQ_GET_CONFIG_T *pargs = arg;
1030 		VCHIQ_GET_CONFIG_T args = *pargs;
1031 		VCHIQ_CONFIG_T config;
1032 
1033 		if (args.config_size > sizeof(config)) {
1034 			ret = -EINVAL;
1035 			break;
1036 		}
1037 		status = vchiq_get_config(instance, args.config_size, &config);
1038 		if (status == VCHIQ_SUCCESS) {
1039 			if (copy_to_user((void __user *)args.pconfig,
1040 				&config, args.config_size) != 0) {
1041 				ret = -EFAULT;
1042 				break;
1043 			}
1044 		}
1045 	} break;
1046 
1047 	case VCHIQ_IOC_SET_SERVICE_OPTION: {
1048 		VCHIQ_SET_SERVICE_OPTION_T *pargs = arg;
1049 		VCHIQ_SET_SERVICE_OPTION_T args = *pargs;
1050 
1051 		service = find_service_for_instance(instance, args.handle);
1052 		if (!service) {
1053 			ret = -EINVAL;
1054 			break;
1055 		}
1056 
1057 		status = vchiq_set_service_option(
1058 				args.handle, args.option, args.value);
1059 	} break;
1060 
1061 	case VCHIQ_IOC_DUMP_PHYS_MEM: {
1062 #if 0
1063 		VCHIQ_DUMP_MEM_T *pargs = arg;
1064 #endif
1065 
1066 		printf("IMPLEMENT ME: %s:%d\n", __FILE__, __LINE__);
1067 #if 0
1068 		dump_phys_mem(pargs->virt_addr, pargs->num_bytes);
1069 #endif
1070 	} break;
1071 
1072 	case VCHIQ_IOC_LIB_VERSION: {
1073 		unsigned int lib_version = (uintptr_t)arg;
1074 
1075 		if (lib_version < VCHIQ_VERSION_MIN)
1076 			ret = -EINVAL;
1077 		else if (lib_version >= VCHIQ_VERSION_CLOSE_DELIVERED)
1078 			instance->use_close_delivered = 1;
1079 	} break;
1080 
1081 	case VCHIQ_IOC_CLOSE_DELIVERED: {
1082 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
1083 
1084 		service = find_closed_service_for_instance(instance, handle);
1085 		if (service != NULL) {
1086 			USER_SERVICE_T *user_service =
1087 				(USER_SERVICE_T *)service->base.userdata;
1088 			close_delivered(user_service);
1089 		}
1090 		else
1091 			ret = -EINVAL;
1092 	} break;
1093 
1094 	default:
1095 		ret = -ENOTTY;
1096 		break;
1097 	}
1098 
1099 	if (service)
1100 		unlock_service(service);
1101 
1102 	if (ret == 0) {
1103 		if (status == VCHIQ_ERROR)
1104 			ret = -EIO;
1105 		else if (status == VCHIQ_RETRY)
1106 			ret = -EINTR;
1107 	}
1108 
1109 	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
1110 		(ret != -EWOULDBLOCK))
1111 		vchiq_log_info(vchiq_arm_log_level,
1112 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1113 			(unsigned long)instance,
1114 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1115 				ioctl_names[_IOC_NR(cmd)] :
1116 				"<invalid>",
1117 			status, ret);
1118 	else
1119 		vchiq_log_trace(vchiq_arm_log_level,
1120 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1121 			(unsigned long)instance,
1122 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1123 				ioctl_names[_IOC_NR(cmd)] :
1124 				"<invalid>",
1125 			status, ret);
1126 
1127 	/* XXXBSD: report BSD-style error to userland */
1128 	if (ret < 0)
1129 		ret = -ret;
1130 
1131 	return ret;
1132 }
1133 
1134 /****************************************************************************
1135 *
1136 *   vchiq_open
1137 *
1138 ***************************************************************************/
1139 
1140 static int
vchiq_open(dev_t dev,int flags,int mode,lwp_t * l)1141 vchiq_open(dev_t dev, int flags, int mode, lwp_t *l)
1142 {
1143 	VCHIQ_INSTANCE_T instance = NULL;
1144 	struct file *fp;
1145 	int err, fd;
1146 
1147 	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1148 
1149 	/* XXXBSD: do we really need this check? */
1150 	if (device_lookup_private(&vchiq_cd, minor(dev)) != NULL) {
1151 		VCHIQ_STATE_T *state;
1152 		int i;
1153 
1154 		for (i=0; i<10; ++i) {
1155 			state = vchiq_get_state();
1156 			if (state)
1157 				break;
1158 			delay(500);
1159 		}
1160 
1161 		if (!state) {
1162 			vchiq_log_error(vchiq_arm_log_level,
1163 				"vchiq has no connection to VideoCore");
1164 			return -ENOTCONN;
1165 		}
1166 
1167 		instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1168 		if (!instance)
1169 			return -ENOMEM;
1170 
1171 		err = fd_allocfile(&fp, &fd);
1172 		if (err) {
1173 			kfree(instance);
1174 			return -err;
1175 		}
1176 
1177 		instance->state = state;
1178 		instance->pid = current->l_proc->p_pid;
1179 
1180 #ifdef notyet
1181 		ret = vchiq_debugfs_add_instance(instance);
1182 		if (ret != 0) {
1183 			kfree(instance);
1184 			return ret;
1185 		}
1186 #endif
1187 
1188 		_sema_init(&instance->insert_event, 0);
1189 		_sema_init(&instance->remove_event, 0);
1190 		lmutex_init(&instance->completion_mutex);
1191 		lmutex_init(&instance->bulk_waiter_list_mutex);
1192 		INIT_LIST_HEAD(&instance->bulk_waiter_list);
1193 
1194 	}
1195 	else {
1196 		vchiq_log_error(vchiq_arm_log_level,
1197 			"Unknown minor device");
1198 		return -ENXIO;
1199 	}
1200 
1201 	return fd_clone(fp, fd, flags, &vchiq_fileops, instance);
1202 }
1203 
1204 /****************************************************************************
1205 *
1206 *   vchiq_release
1207 *
1208 ***************************************************************************/
1209 
1210 static int
vchiq_close(struct file * fp)1211 vchiq_close(struct file *fp)
1212 {
1213 	int ret = 0;
1214 	if (1) {
1215 		VCHIQ_INSTANCE_T instance = fp->f_data;
1216 		VCHIQ_STATE_T *state = vchiq_get_state();
1217 		VCHIQ_SERVICE_T *service;
1218 		int i;
1219 
1220 		vchiq_log_info(vchiq_arm_log_level,
1221 			"vchiq_release: instance=%lx",
1222 			(unsigned long)instance);
1223 
1224 		if (!state) {
1225 			ret = -EPERM;
1226 			goto out;
1227 		}
1228 
1229 		/* Ensure videocore is awake to allow termination. */
1230 		vchiq_use_internal(instance->state, NULL,
1231 				USE_TYPE_VCHIQ);
1232 
1233 		lmutex_lock(&instance->completion_mutex);
1234 
1235 		/* Wake the completion thread and ask it to exit */
1236 		instance->closing = 1;
1237 		up(&instance->insert_event);
1238 
1239 		lmutex_unlock(&instance->completion_mutex);
1240 
1241 		/* Wake the slot handler if the completion queue is full. */
1242 		up(&instance->remove_event);
1243 
1244 		/* Mark all services for termination... */
1245 		i = 0;
1246 		while ((service = next_service_by_instance(state, instance,
1247 			&i)) !=	NULL) {
1248 			USER_SERVICE_T *user_service = service->base.userdata;
1249 
1250 			/* Wake the slot handler if the msg queue is full. */
1251 			up(&user_service->remove_event);
1252 
1253 			vchiq_terminate_service_internal(service);
1254 			unlock_service(service);
1255 		}
1256 
1257 		/* ...and wait for them to die */
1258 		i = 0;
1259 		while ((service = next_service_by_instance(state, instance, &i))
1260 			!= NULL) {
1261 			USER_SERVICE_T *user_service = service->base.userdata;
1262 
1263 			down(&service->remove_event);
1264 
1265 			BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1266 
1267 			spin_lock(&msg_queue_spinlock);
1268 
1269 			while (user_service->msg_remove !=
1270 				user_service->msg_insert) {
1271 				VCHIQ_HEADER_T *header = user_service->
1272 					msg_queue[user_service->msg_remove &
1273 						(MSG_QUEUE_SIZE - 1)];
1274 				user_service->msg_remove++;
1275 				spin_unlock(&msg_queue_spinlock);
1276 
1277 				if (header)
1278 					vchiq_release_message(
1279 						service->handle,
1280 						header);
1281 				spin_lock(&msg_queue_spinlock);
1282 			}
1283 
1284 			spin_unlock(&msg_queue_spinlock);
1285 
1286 			unlock_service(service);
1287 		}
1288 
1289 		/* Release any closed services */
1290 		while (instance->completion_remove !=
1291 			instance->completion_insert) {
1292 			VCHIQ_COMPLETION_DATA_T *completion;
1293 			VCHIQ_SERVICE_T *service1;
1294 			completion = &instance->completions[
1295 				instance->completion_remove &
1296 				(MAX_COMPLETIONS - 1)];
1297 			service1 = completion->service_userdata;
1298 			if (completion->reason == VCHIQ_SERVICE_CLOSED)
1299 			{
1300 				USER_SERVICE_T *user_service =
1301 					service->base.userdata;
1302 
1303 				/* Wake any blocked user-thread */
1304 				if (instance->use_close_delivered)
1305 					up(&user_service->close_event);
1306 				unlock_service(service1);
1307 			}
1308 			instance->completion_remove++;
1309 		}
1310 
1311 		/* Release the PEER service count. */
1312 		vchiq_release_internal(instance->state, NULL);
1313 
1314 		{
1315 			struct list_head *pos, *next;
1316 			list_for_each_safe(pos, next,
1317 				&instance->bulk_waiter_list) {
1318 				struct bulk_waiter_node *waiter;
1319 				waiter = list_entry(pos,
1320 					struct bulk_waiter_node,
1321 					list);
1322 				list_del(pos);
1323 				vchiq_log_info(vchiq_arm_log_level,
1324 					"bulk_waiter - cleaned up %p "
1325 					"for pid %d",
1326 					waiter, waiter->pid);
1327 		                _sema_destroy(&waiter->bulk_waiter.event);
1328 				kfree(waiter);
1329 			}
1330 		}
1331 
1332 	}
1333 	else {
1334 		vchiq_log_error(vchiq_arm_log_level,
1335 			"Unknown minor device");
1336 		ret = -ENXIO;
1337 	}
1338 
1339 out:
1340 	return ret;
1341 }
1342 
1343 /****************************************************************************
1344 *
1345 *   vchiq_dump
1346 *
1347 ***************************************************************************/
1348 
1349 void
vchiq_dump(void * dump_context,const char * str,int len)1350 vchiq_dump(void *dump_context, const char *str, int len)
1351 {
1352 	DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1353 
1354 	if (context->actual < context->space) {
1355 		int copy_bytes;
1356 		if (context->offset > 0) {
1357 			int skip_bytes = min(len, (int)context->offset);
1358 			str += skip_bytes;
1359 			len -= skip_bytes;
1360 			context->offset -= skip_bytes;
1361 			if (context->offset > 0)
1362 				return;
1363 		}
1364 		copy_bytes = min(len, (int)(context->space - context->actual));
1365 		if (copy_bytes == 0)
1366 			return;
1367 		memcpy(context->buf + context->actual, str, copy_bytes);
1368 		context->actual += copy_bytes;
1369 		len -= copy_bytes;
1370 
1371 		/* If tne terminating NUL is included in the length, then it
1372 		** marks the end of a line and should be replaced with a
1373 		** carriage return. */
1374 		if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1375 			char cr = '\n';
1376 			memcpy(context->buf + context->actual - 1, &cr, 1);
1377 		}
1378 	}
1379 }
1380 
1381 /****************************************************************************
1382 *
1383 *   vchiq_dump_platform_instance_state
1384 *
1385 ***************************************************************************/
1386 
1387 void
vchiq_dump_platform_instances(void * dump_context)1388 vchiq_dump_platform_instances(void *dump_context)
1389 {
1390 	VCHIQ_STATE_T *state = vchiq_get_state();
1391 	char buf[80];
1392 	int len;
1393 	int i;
1394 
1395 	/* There is no list of instances, so instead scan all services,
1396 		marking those that have been dumped. */
1397 
1398 	for (i = 0; i < state->unused_service; i++) {
1399 		VCHIQ_SERVICE_T *service = state->services[i];
1400 		VCHIQ_INSTANCE_T instance;
1401 
1402 		if (service && (service->base.callback == service_callback)) {
1403 			instance = service->instance;
1404 			if (instance)
1405 				instance->mark = 0;
1406 		}
1407 	}
1408 
1409 	for (i = 0; i < state->unused_service; i++) {
1410 		VCHIQ_SERVICE_T *service = state->services[i];
1411 		VCHIQ_INSTANCE_T instance;
1412 
1413 		if (service && (service->base.callback == service_callback)) {
1414 			instance = service->instance;
1415 			if (instance && !instance->mark) {
1416 				len = snprintf(buf, sizeof(buf),
1417 					"Instance %p: pid %d,%s completions "
1418 						"%d/%d",
1419 					instance, instance->pid,
1420 					instance->connected ? " connected, " :
1421 						"",
1422 					instance->completion_insert -
1423 						instance->completion_remove,
1424 					MAX_COMPLETIONS);
1425 
1426 				vchiq_dump(dump_context, buf, len + 1);
1427 
1428 				instance->mark = 1;
1429 			}
1430 		}
1431 	}
1432 }
1433 
1434 /****************************************************************************
1435 *
1436 *   vchiq_dump_platform_service_state
1437 *
1438 ***************************************************************************/
1439 
1440 void
vchiq_dump_platform_service_state(void * dump_context,VCHIQ_SERVICE_T * service)1441 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1442 {
1443 	USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1444 	char buf[80];
1445 	int len;
1446 
1447 	len = snprintf(buf, sizeof(buf), "  instance %p",
1448 		service->instance);
1449 
1450 	if ((service->base.callback == service_callback) &&
1451 		user_service->is_vchi) {
1452 		len += snprintf(buf + len, sizeof(buf) - len,
1453 			", %d/%d messages",
1454 			user_service->msg_insert - user_service->msg_remove,
1455 			MSG_QUEUE_SIZE);
1456 
1457 		if (user_service->dequeue_pending)
1458 			len += snprintf(buf + len, sizeof(buf) - len,
1459 				" (dequeue pending)");
1460 	}
1461 
1462 	vchiq_dump(dump_context, buf, len + 1);
1463 }
1464 
1465 #ifdef notyet
1466 /****************************************************************************
1467 *
1468 *   dump_user_mem
1469 *
1470 ***************************************************************************/
1471 
1472 static void
dump_phys_mem(void * virt_addr,uint32_t num_bytes)1473 dump_phys_mem(void *virt_addr, uint32_t num_bytes)
1474 {
1475 	int            rc;
1476 	uint8_t       *end_virt_addr = virt_addr + num_bytes;
1477 	int            num_pages;
1478 	int            offset;
1479 	int            end_offset;
1480 	int            page_idx;
1481 	int            prev_idx;
1482 	struct page   *page;
1483 	struct page  **pages;
1484 	uint8_t       *kmapped_virt_ptr;
1485 
1486 	/* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1487 
1488 	virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1489 	end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1490 		~0x0fuL);
1491 
1492 	offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1493 	end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1494 
1495 	num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1496 
1497 	pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1498 	if (pages == NULL) {
1499 		vchiq_log_error(vchiq_arm_log_level,
1500 			"Unable to allocation memory for %d pages",
1501 			num_pages);
1502 		return;
1503 	}
1504 
1505 	down_read(&current->mm->mmap_sem);
1506 	rc = get_user_pages(current,      /* task */
1507 		current->mm,              /* mm */
1508 		(unsigned long)virt_addr, /* start */
1509 		num_pages,                /* len */
1510 		0,                        /* write */
1511 		0,                        /* force */
1512 		pages,                    /* pages (array of page pointers) */
1513 		NULL);                    /* vmas */
1514 	up_read(&current->mm->mmap_sem);
1515 
1516 	prev_idx = -1;
1517 	page = NULL;
1518 
1519 	while (offset < end_offset) {
1520 
1521 		int page_offset = offset % PAGE_SIZE;
1522 		page_idx = offset / PAGE_SIZE;
1523 
1524 		if (page_idx != prev_idx) {
1525 
1526 			if (page != NULL)
1527 				kunmap(page);
1528 			page = pages[page_idx];
1529 			kmapped_virt_ptr = kmap(page);
1530 
1531 			prev_idx = page_idx;
1532 		}
1533 
1534 		if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1535 			vchiq_log_dump_mem("ph",
1536 				(uint32_t)(unsigned long)&kmapped_virt_ptr[
1537 					page_offset],
1538 				&kmapped_virt_ptr[page_offset], 16);
1539 
1540 		offset += 16;
1541 	}
1542 	if (page != NULL)
1543 		kunmap(page);
1544 
1545 	for (page_idx = 0; page_idx < num_pages; page_idx++)
1546 		page_cache_release(pages[page_idx]);
1547 
1548 	kfree(pages);
1549 }
1550 #endif
1551 
1552 /****************************************************************************
1553 *
1554 *   vchiq_read
1555 *
1556 ***************************************************************************/
1557 
1558 static int
vchiq_read(struct file * file,off_t * ppos,struct uio * uio,kauth_cred_t cred,int flags)1559 vchiq_read(struct file *file, off_t *ppos, struct uio *uio, kauth_cred_t cred,
1560     int flags)
1561 {
1562 	int result;
1563 
1564 	char *buf = kmem_zalloc(PAGE_SIZE, KM_SLEEP);
1565 
1566 	DUMP_CONTEXT_T context;
1567 	context.buf = buf;
1568 	context.actual = 0;
1569 	context.space = PAGE_SIZE;
1570 	context.offset = *ppos;
1571 
1572 	vchiq_dump_state(&context, &g_state);
1573 
1574 	*ppos += context.actual;
1575 
1576 	result = uiomove(buf, context.actual, uio);
1577 	kmem_free(buf, PAGE_SIZE);
1578 
1579 	return result;
1580 }
1581 
1582 VCHIQ_STATE_T *
vchiq_get_state(void)1583 vchiq_get_state(void)
1584 {
1585 
1586 	if (g_state.remote == NULL)
1587 		printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1588 	else if (g_state.remote->initialised != 1)
1589 		printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1590 			__func__, g_state.remote->initialised);
1591 
1592 	return ((g_state.remote != NULL) &&
1593 		(g_state.remote->initialised == 1)) ? &g_state : NULL;
1594 }
1595 
1596 /*
1597  * Autosuspend related functionality
1598  */
1599 
1600 int
vchiq_videocore_wanted(VCHIQ_STATE_T * state)1601 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1602 {
1603 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1604 	if (!arm_state)
1605 		/* autosuspend not supported - always return wanted */
1606 		return 1;
1607 	else if (arm_state->blocked_count)
1608 		return 1;
1609 	else if (!arm_state->videocore_use_count)
1610 		/* usage count zero - check for override unless we're forcing */
1611 		if (arm_state->resume_blocked)
1612 			return 0;
1613 		else
1614 			return vchiq_platform_videocore_wanted(state);
1615 	else
1616 		/* non-zero usage count - videocore still required */
1617 		return 1;
1618 }
1619 
1620 static VCHIQ_STATUS_T
vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,VCHIQ_HEADER_T * header,VCHIQ_SERVICE_HANDLE_T service_user,void * bulk_user)1621 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1622 	VCHIQ_HEADER_T *header,
1623 	VCHIQ_SERVICE_HANDLE_T service_user,
1624 	void *bulk_user)
1625 {
1626 	vchiq_log_error(vchiq_susp_log_level,
1627 		"%s callback reason %d", __func__, reason);
1628 	return 0;
1629 }
1630 
1631 static int
vchiq_keepalive_thread_func(void * v)1632 vchiq_keepalive_thread_func(void *v)
1633 {
1634 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1635 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1636 
1637 	VCHIQ_STATUS_T status;
1638 	VCHIQ_INSTANCE_T instance;
1639 	VCHIQ_SERVICE_HANDLE_T ka_handle;
1640 
1641 	VCHIQ_SERVICE_PARAMS_T params = {
1642 		.fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1643 		.callback    = vchiq_keepalive_vchiq_callback,
1644 		.version     = KEEPALIVE_VER,
1645 		.version_min = KEEPALIVE_VER_MIN
1646 	};
1647 
1648 	status = vchiq_initialise(&instance);
1649 	if (status != VCHIQ_SUCCESS) {
1650 		vchiq_log_error(vchiq_susp_log_level,
1651 			"%s vchiq_initialise failed %d", __func__, status);
1652 		goto exit;
1653 	}
1654 
1655 	status = vchiq_connect(instance);
1656 	if (status != VCHIQ_SUCCESS) {
1657 		vchiq_log_error(vchiq_susp_log_level,
1658 			"%s vchiq_connect failed %d", __func__, status);
1659 		goto shutdown;
1660 	}
1661 
1662 	status = vchiq_add_service(instance, &params, &ka_handle);
1663 	if (status != VCHIQ_SUCCESS) {
1664 		vchiq_log_error(vchiq_susp_log_level,
1665 			"%s vchiq_open_service failed %d", __func__, status);
1666 		goto shutdown;
1667 	}
1668 
1669 	while (1) {
1670 		long rc = 0, uc = 0;
1671 		if (wait_for_completion_interruptible(&arm_state->ka_evt)
1672 				!= 0) {
1673 			vchiq_log_error(vchiq_susp_log_level,
1674 				"%s interrupted", __func__);
1675 			flush_signals(current);
1676 			continue;
1677 		}
1678 
1679 		/* read and clear counters.  Do release_count then use_count to
1680 		 * prevent getting more releases than uses */
1681 		rc = atomic_xchg(&arm_state->ka_release_count, 0);
1682 		uc = atomic_xchg(&arm_state->ka_use_count, 0);
1683 
1684 		/* Call use/release service the requisite number of times.
1685 		 * Process use before release so use counts don't go negative */
1686 		while (uc--) {
1687 			atomic_inc(&arm_state->ka_use_ack_count);
1688 			status = vchiq_use_service(ka_handle);
1689 			if (status != VCHIQ_SUCCESS) {
1690 				vchiq_log_error(vchiq_susp_log_level,
1691 					"%s vchiq_use_service error %d",
1692 					__func__, status);
1693 			}
1694 		}
1695 		while (rc--) {
1696 			status = vchiq_release_service(ka_handle);
1697 			if (status != VCHIQ_SUCCESS) {
1698 				vchiq_log_error(vchiq_susp_log_level,
1699 					"%s vchiq_release_service error %d",
1700 					__func__, status);
1701 			}
1702 		}
1703 	}
1704 
1705 shutdown:
1706 	vchiq_shutdown(instance);
1707 exit:
1708 	return 0;
1709 }
1710 
1711 
1712 
1713 VCHIQ_STATUS_T
vchiq_arm_init_state(VCHIQ_STATE_T * state,VCHIQ_ARM_STATE_T * arm_state)1714 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1715 {
1716 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
1717 
1718 	if (arm_state) {
1719 		rwlock_init(&arm_state->susp_res_lock);
1720 
1721 		init_completion(&arm_state->ka_evt);
1722 		atomic_set(&arm_state->ka_use_count, 0);
1723 		atomic_set(&arm_state->ka_use_ack_count, 0);
1724 		atomic_set(&arm_state->ka_release_count, 0);
1725 
1726 		init_completion(&arm_state->vc_suspend_complete);
1727 
1728 		init_completion(&arm_state->vc_resume_complete);
1729 		/* Initialise to 'done' state.  We only want to block on resume
1730 		 * completion while videocore is suspended. */
1731 		set_resume_state(arm_state, VC_RESUME_RESUMED);
1732 
1733 		init_completion(&arm_state->resume_blocker);
1734 		/* Initialise to 'done' state.  We only want to block on this
1735 		 * completion while resume is blocked */
1736 		complete_all(&arm_state->resume_blocker);
1737 
1738 		init_completion(&arm_state->blocked_blocker);
1739 		/* Initialise to 'done' state.  We only want to block on this
1740 		 * completion while things are waiting on the resume blocker */
1741 		complete_all(&arm_state->blocked_blocker);
1742 
1743 		arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1744 		arm_state->suspend_timer_running = 0;
1745 		init_timer(&arm_state->suspend_timer);
1746 		arm_state->suspend_timer.data = (unsigned long)(state);
1747 		arm_state->suspend_timer.function = suspend_timer_callback;
1748 
1749 		arm_state->first_connect = 0;
1750 
1751 	}
1752 	return status;
1753 }
1754 
1755 /*
1756 ** Functions to modify the state variables;
1757 **	set_suspend_state
1758 **	set_resume_state
1759 **
1760 ** There are more state variables than we might like, so ensure they remain in
1761 ** step.  Suspend and resume state are maintained separately, since most of
1762 ** these state machines can operate independently.  However, there are a few
1763 ** states where state transitions in one state machine cause a reset to the
1764 ** other state machine.  In addition, there are some completion events which
1765 ** need to occur on state machine reset and end-state(s), so these are also
1766 ** dealt with in these functions.
1767 **
1768 ** In all states we set the state variable according to the input, but in some
1769 ** cases we perform additional steps outlined below;
1770 **
1771 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1772 **			The suspend completion is completed after any suspend
1773 **			attempt.  When we reset the state machine we also reset
1774 **			the completion.  This reset occurs when videocore is
1775 **			resumed, and also if we initiate suspend after a suspend
1776 **			failure.
1777 **
1778 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1779 **			suspend - ie from this point on we must try to suspend
1780 **			before resuming can occur.  We therefore also reset the
1781 **			resume state machine to VC_RESUME_IDLE in this state.
1782 **
1783 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1784 **			complete_all on the suspend completion to notify
1785 **			anything waiting for suspend to happen.
1786 **
1787 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1788 **			initiate resume, so no need to alter resume state.
1789 **			We call complete_all on the suspend completion to notify
1790 **			of suspend rejection.
1791 **
1792 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1793 **			suspend completion and reset the resume state machine.
1794 **
1795 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1796 **			resume completion is in it's 'done' state whenever
1797 **			videcore is running.  Therfore, the VC_RESUME_IDLE state
1798 **			implies that videocore is suspended.
1799 **			Hence, any thread which needs to wait until videocore is
1800 **			running can wait on this completion - it will only block
1801 **			if videocore is suspended.
1802 **
1803 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1804 **			Call complete_all on the resume completion to unblock
1805 **			any threads waiting for resume.	 Also reset the suspend
1806 **			state machine to it's idle state.
1807 **
1808 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1809 */
1810 
1811 inline void
set_suspend_state(VCHIQ_ARM_STATE_T * arm_state,enum vc_suspend_status new_state)1812 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1813 	enum vc_suspend_status new_state)
1814 {
1815 	/* set the state in all cases */
1816 	arm_state->vc_suspend_state = new_state;
1817 
1818 	/* state specific additional actions */
1819 	switch (new_state) {
1820 	case VC_SUSPEND_FORCE_CANCELED:
1821 		complete_all(&arm_state->vc_suspend_complete);
1822 		break;
1823 	case VC_SUSPEND_REJECTED:
1824 		complete_all(&arm_state->vc_suspend_complete);
1825 		break;
1826 	case VC_SUSPEND_FAILED:
1827 		complete_all(&arm_state->vc_suspend_complete);
1828 		arm_state->vc_resume_state = VC_RESUME_RESUMED;
1829 		complete_all(&arm_state->vc_resume_complete);
1830 		break;
1831 	case VC_SUSPEND_IDLE:
1832 		reinit_completion(&arm_state->vc_suspend_complete);
1833 		break;
1834 	case VC_SUSPEND_REQUESTED:
1835 		break;
1836 	case VC_SUSPEND_IN_PROGRESS:
1837 		set_resume_state(arm_state, VC_RESUME_IDLE);
1838 		break;
1839 	case VC_SUSPEND_SUSPENDED:
1840 		complete_all(&arm_state->vc_suspend_complete);
1841 		break;
1842 	default:
1843 		BUG();
1844 		break;
1845 	}
1846 }
1847 
1848 inline void
set_resume_state(VCHIQ_ARM_STATE_T * arm_state,enum vc_resume_status new_state)1849 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1850 	enum vc_resume_status new_state)
1851 {
1852 	/* set the state in all cases */
1853 	arm_state->vc_resume_state = new_state;
1854 
1855 	/* state specific additional actions */
1856 	switch (new_state) {
1857 	case VC_RESUME_FAILED:
1858 		break;
1859 	case VC_RESUME_IDLE:
1860 		reinit_completion(&arm_state->vc_resume_complete);
1861 		break;
1862 	case VC_RESUME_REQUESTED:
1863 		break;
1864 	case VC_RESUME_IN_PROGRESS:
1865 		break;
1866 	case VC_RESUME_RESUMED:
1867 		complete_all(&arm_state->vc_resume_complete);
1868 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1869 		break;
1870 	default:
1871 		BUG();
1872 		break;
1873 	}
1874 }
1875 
1876 
1877 /* should be called with the write lock held */
1878 inline void
start_suspend_timer(VCHIQ_ARM_STATE_T * arm_state)1879 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1880 {
1881 	del_timer(&arm_state->suspend_timer);
1882 	arm_state->suspend_timer.expires = jiffies +
1883 		msecs_to_jiffies(arm_state->
1884 			suspend_timer_timeout);
1885 	add_timer(&arm_state->suspend_timer);
1886 	arm_state->suspend_timer_running = 1;
1887 }
1888 
1889 /* should be called with the write lock held */
1890 static inline void
stop_suspend_timer(VCHIQ_ARM_STATE_T * arm_state)1891 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1892 {
1893 	if (arm_state->suspend_timer_running) {
1894 		del_timer(&arm_state->suspend_timer);
1895 		arm_state->suspend_timer_running = 0;
1896 	}
1897 }
1898 
1899 static inline int
need_resume(VCHIQ_STATE_T * state)1900 need_resume(VCHIQ_STATE_T *state)
1901 {
1902 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1903 	return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1904 			(arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1905 			vchiq_videocore_wanted(state);
1906 }
1907 
1908 static int
block_resume(VCHIQ_ARM_STATE_T * arm_state)1909 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1910 {
1911 	int status = VCHIQ_SUCCESS;
1912 	const unsigned long timeout_val =
1913 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1914 	int resume_count = 0;
1915 
1916 	/* Allow any threads which were blocked by the last force suspend to
1917 	 * complete if they haven't already.  Only give this one shot; if
1918 	 * blocked_count is incremented after blocked_blocker is completed
1919 	 * (which only happens when blocked_count hits 0) then those threads
1920 	 * will have to wait until next time around */
1921 	if (arm_state->blocked_count) {
1922 		reinit_completion(&arm_state->blocked_blocker);
1923 		write_unlock_bh(&arm_state->susp_res_lock);
1924 		vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
1925 			"blocked clients", __func__);
1926 		if (wait_for_completion_interruptible_timeout(
1927 				&arm_state->blocked_blocker, timeout_val)
1928 					<= 0) {
1929 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1930 				"previously blocked clients failed" , __func__);
1931 			status = VCHIQ_ERROR;
1932 			write_lock_bh(&arm_state->susp_res_lock);
1933 			goto out;
1934 		}
1935 		vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
1936 			"clients resumed", __func__);
1937 		write_lock_bh(&arm_state->susp_res_lock);
1938 	}
1939 
1940 	/* We need to wait for resume to complete if it's in process */
1941 	while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
1942 			arm_state->vc_resume_state > VC_RESUME_IDLE) {
1943 		if (resume_count > 1) {
1944 			status = VCHIQ_ERROR;
1945 			vchiq_log_error(vchiq_susp_log_level, "%s waited too "
1946 				"many times for resume" , __func__);
1947 			goto out;
1948 		}
1949 		write_unlock_bh(&arm_state->susp_res_lock);
1950 		vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
1951 			__func__);
1952 		if (wait_for_completion_interruptible_timeout(
1953 				&arm_state->vc_resume_complete, timeout_val)
1954 					<= 0) {
1955 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1956 				"resume failed (%s)", __func__,
1957 				resume_state_names[arm_state->vc_resume_state +
1958 							VC_RESUME_NUM_OFFSET]);
1959 			status = VCHIQ_ERROR;
1960 			write_lock_bh(&arm_state->susp_res_lock);
1961 			goto out;
1962 		}
1963 		vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
1964 		write_lock_bh(&arm_state->susp_res_lock);
1965 		resume_count++;
1966 	}
1967 	reinit_completion(&arm_state->resume_blocker);
1968 	arm_state->resume_blocked = 1;
1969 
1970 out:
1971 	return status;
1972 }
1973 
1974 static inline void
unblock_resume(VCHIQ_ARM_STATE_T * arm_state)1975 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
1976 {
1977 	complete_all(&arm_state->resume_blocker);
1978 	arm_state->resume_blocked = 0;
1979 }
1980 
1981 /* Initiate suspend via slot handler. Should be called with the write lock
1982  * held */
1983 VCHIQ_STATUS_T
vchiq_arm_vcsuspend(VCHIQ_STATE_T * state)1984 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
1985 {
1986 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1987 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1988 
1989 	if (!arm_state)
1990 		goto out;
1991 
1992 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1993 	status = VCHIQ_SUCCESS;
1994 
1995 
1996 	switch (arm_state->vc_suspend_state) {
1997 	case VC_SUSPEND_REQUESTED:
1998 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
1999 			"requested", __func__);
2000 		break;
2001 	case VC_SUSPEND_IN_PROGRESS:
2002 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
2003 			"progress", __func__);
2004 		break;
2005 
2006 	default:
2007 		/* We don't expect to be in other states, so log but continue
2008 		 * anyway */
2009 		vchiq_log_error(vchiq_susp_log_level,
2010 			"%s unexpected suspend state %s", __func__,
2011 			suspend_state_names[arm_state->vc_suspend_state +
2012 						VC_SUSPEND_NUM_OFFSET]);
2013 		/* fall through */
2014 	case VC_SUSPEND_REJECTED:
2015 	case VC_SUSPEND_FAILED:
2016 		/* Ensure any idle state actions have been run */
2017 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2018 		/* fall through */
2019 	case VC_SUSPEND_IDLE:
2020 		vchiq_log_info(vchiq_susp_log_level,
2021 			"%s: suspending", __func__);
2022 		set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
2023 		/* kick the slot handler thread to initiate suspend */
2024 		request_poll(state, NULL, 0);
2025 		break;
2026 	}
2027 
2028 out:
2029 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2030 	return status;
2031 }
2032 
2033 void
vchiq_platform_check_suspend(VCHIQ_STATE_T * state)2034 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
2035 {
2036 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2037 	int susp = 0;
2038 
2039 	if (!arm_state)
2040 		goto out;
2041 
2042 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2043 
2044 	write_lock_bh(&arm_state->susp_res_lock);
2045 	if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
2046 			arm_state->vc_resume_state == VC_RESUME_RESUMED) {
2047 		set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
2048 		susp = 1;
2049 	}
2050 	write_unlock_bh(&arm_state->susp_res_lock);
2051 
2052 	if (susp)
2053 		vchiq_platform_suspend(state);
2054 
2055 out:
2056 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2057 	return;
2058 }
2059 
2060 
2061 static void
output_timeout_error(VCHIQ_STATE_T * state)2062 output_timeout_error(VCHIQ_STATE_T *state)
2063 {
2064 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2065 	char service_err[50] = "";
2066 	int vc_use_count = arm_state->videocore_use_count;
2067 	int active_services = state->unused_service;
2068 	int i;
2069 
2070 	if (!arm_state->videocore_use_count) {
2071 		snprintf(service_err, 50, " Videocore usecount is 0");
2072 		goto output_msg;
2073 	}
2074 	for (i = 0; i < active_services; i++) {
2075 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
2076 		if (service_ptr && service_ptr->service_use_count &&
2077 			(service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
2078 			snprintf(service_err, 50, " %c%c%c%c(%8x) service has "
2079 				"use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
2080 					service_ptr->base.fourcc),
2081 				 service_ptr->client_id,
2082 				 service_ptr->service_use_count,
2083 				 service_ptr->service_use_count ==
2084 					 vc_use_count ? "" : " (+ more)");
2085 			break;
2086 		}
2087 	}
2088 
2089 output_msg:
2090 	vchiq_log_error(vchiq_susp_log_level,
2091 		"timed out waiting for vc suspend (%d).%s",
2092 		 arm_state->autosuspend_override, service_err);
2093 
2094 }
2095 
2096 /* Try to get videocore into suspended state, regardless of autosuspend state.
2097 ** We don't actually force suspend, since videocore may get into a bad state
2098 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
2099 ** determine a good point to suspend.  If this doesn't happen within 100ms we
2100 ** report failure.
2101 **
2102 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
2103 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
2104 */
2105 VCHIQ_STATUS_T
vchiq_arm_force_suspend(VCHIQ_STATE_T * state)2106 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
2107 {
2108 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2109 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
2110 	long rc = 0;
2111 	int repeat = -1;
2112 
2113 	if (!arm_state)
2114 		goto out;
2115 
2116 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2117 
2118 	write_lock_bh(&arm_state->susp_res_lock);
2119 
2120 	status = block_resume(arm_state);
2121 	if (status != VCHIQ_SUCCESS)
2122 		goto unlock;
2123 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2124 		/* Already suspended - just block resume and exit */
2125 		vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2126 			__func__);
2127 		status = VCHIQ_SUCCESS;
2128 		goto unlock;
2129 	} else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2130 		/* initiate suspend immediately in the case that we're waiting
2131 		 * for the timeout */
2132 		stop_suspend_timer(arm_state);
2133 		if (!vchiq_videocore_wanted(state)) {
2134 			vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2135 				"idle, initiating suspend", __func__);
2136 			status = vchiq_arm_vcsuspend(state);
2137 		} else if (arm_state->autosuspend_override <
2138 						FORCE_SUSPEND_FAIL_MAX) {
2139 			vchiq_log_info(vchiq_susp_log_level, "%s letting "
2140 				"videocore go idle", __func__);
2141 			status = VCHIQ_SUCCESS;
2142 		} else {
2143 			vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2144 				"many times - attempting suspend", __func__);
2145 			status = vchiq_arm_vcsuspend(state);
2146 		}
2147 	} else {
2148 		vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2149 			"in progress - wait for completion", __func__);
2150 		status = VCHIQ_SUCCESS;
2151 	}
2152 
2153 	/* Wait for suspend to happen due to system idle (not forced..) */
2154 	if (status != VCHIQ_SUCCESS)
2155 		goto unblock_resume;
2156 
2157 	do {
2158 		write_unlock_bh(&arm_state->susp_res_lock);
2159 
2160 		rc = wait_for_completion_interruptible_timeout(
2161 				&arm_state->vc_suspend_complete,
2162 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2163 
2164 		write_lock_bh(&arm_state->susp_res_lock);
2165 		if (rc < 0) {
2166 			vchiq_log_warning(vchiq_susp_log_level, "%s "
2167 				"interrupted waiting for suspend", __func__);
2168 			status = VCHIQ_ERROR;
2169 			goto unblock_resume;
2170 		} else if (rc == 0) {
2171 			if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2172 				/* Repeat timeout once if in progress */
2173 				if (repeat < 0) {
2174 					repeat = 1;
2175 					continue;
2176 				}
2177 			}
2178 			arm_state->autosuspend_override++;
2179 			output_timeout_error(state);
2180 
2181 			status = VCHIQ_RETRY;
2182 			goto unblock_resume;
2183 		}
2184 	} while (0 < (repeat--));
2185 
2186 	/* Check and report state in case we need to abort ARM suspend */
2187 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2188 		status = VCHIQ_RETRY;
2189 		vchiq_log_error(vchiq_susp_log_level,
2190 			"%s videocore suspend failed (state %s)", __func__,
2191 			suspend_state_names[arm_state->vc_suspend_state +
2192 						VC_SUSPEND_NUM_OFFSET]);
2193 		/* Reset the state only if it's still in an error state.
2194 		 * Something could have already initiated another suspend. */
2195 		if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2196 			set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2197 
2198 		goto unblock_resume;
2199 	}
2200 
2201 	/* successfully suspended - unlock and exit */
2202 	goto unlock;
2203 
2204 unblock_resume:
2205 	/* all error states need to unblock resume before exit */
2206 	unblock_resume(arm_state);
2207 
2208 unlock:
2209 	write_unlock_bh(&arm_state->susp_res_lock);
2210 
2211 out:
2212 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2213 	return status;
2214 }
2215 
2216 void
vchiq_check_suspend(VCHIQ_STATE_T * state)2217 vchiq_check_suspend(VCHIQ_STATE_T *state)
2218 {
2219 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2220 
2221 	if (!arm_state)
2222 		goto out;
2223 
2224 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2225 
2226 	write_lock_bh(&arm_state->susp_res_lock);
2227 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2228 			arm_state->first_connect &&
2229 			!vchiq_videocore_wanted(state)) {
2230 		vchiq_arm_vcsuspend(state);
2231 	}
2232 	write_unlock_bh(&arm_state->susp_res_lock);
2233 
2234 out:
2235 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2236 	return;
2237 }
2238 
2239 
2240 int
vchiq_arm_allow_resume(VCHIQ_STATE_T * state)2241 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2242 {
2243 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2244 	int resume = 0;
2245 	int ret = -1;
2246 
2247 	if (!arm_state)
2248 		goto out;
2249 
2250 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2251 
2252 	write_lock_bh(&arm_state->susp_res_lock);
2253 	unblock_resume(arm_state);
2254 	resume = vchiq_check_resume(state);
2255 	write_unlock_bh(&arm_state->susp_res_lock);
2256 
2257 	if (resume) {
2258 		if (wait_for_completion_interruptible(
2259 			&arm_state->vc_resume_complete) < 0) {
2260 			vchiq_log_error(vchiq_susp_log_level,
2261 				"%s interrupted", __func__);
2262 			/* failed, cannot accurately derive suspend
2263 			 * state, so exit early. */
2264 			goto out;
2265 		}
2266 	}
2267 
2268 	read_lock_bh(&arm_state->susp_res_lock);
2269 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2270 		vchiq_log_info(vchiq_susp_log_level,
2271 				"%s: Videocore remains suspended", __func__);
2272 	} else {
2273 		vchiq_log_info(vchiq_susp_log_level,
2274 				"%s: Videocore resumed", __func__);
2275 		ret = 0;
2276 	}
2277 	read_unlock_bh(&arm_state->susp_res_lock);
2278 out:
2279 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2280 	return ret;
2281 }
2282 
2283 /* This function should be called with the write lock held */
2284 int
vchiq_check_resume(VCHIQ_STATE_T * state)2285 vchiq_check_resume(VCHIQ_STATE_T *state)
2286 {
2287 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2288 	int resume = 0;
2289 
2290 	if (!arm_state)
2291 		goto out;
2292 
2293 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2294 
2295 	if (need_resume(state)) {
2296 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2297 		request_poll(state, NULL, 0);
2298 		resume = 1;
2299 	}
2300 
2301 out:
2302 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2303 	return resume;
2304 }
2305 
2306 #ifdef notyet
2307 void
vchiq_platform_check_resume(VCHIQ_STATE_T * state)2308 vchiq_platform_check_resume(VCHIQ_STATE_T *state)
2309 {
2310 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2311 	int res = 0;
2312 
2313 	if (!arm_state)
2314 		goto out;
2315 
2316 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2317 
2318 	write_lock_bh(&arm_state->susp_res_lock);
2319 	if (arm_state->wake_address == 0) {
2320 		vchiq_log_info(vchiq_susp_log_level,
2321 					"%s: already awake", __func__);
2322 		goto unlock;
2323 	}
2324 	if (arm_state->vc_resume_state == VC_RESUME_IN_PROGRESS) {
2325 		vchiq_log_info(vchiq_susp_log_level,
2326 					"%s: already resuming", __func__);
2327 		goto unlock;
2328 	}
2329 
2330 	if (arm_state->vc_resume_state == VC_RESUME_REQUESTED) {
2331 		set_resume_state(arm_state, VC_RESUME_IN_PROGRESS);
2332 		res = 1;
2333 	} else
2334 		vchiq_log_trace(vchiq_susp_log_level,
2335 				"%s: not resuming (resume state %s)", __func__,
2336 				resume_state_names[arm_state->vc_resume_state +
2337 							VC_RESUME_NUM_OFFSET]);
2338 
2339 unlock:
2340 	write_unlock_bh(&arm_state->susp_res_lock);
2341 
2342 	if (res)
2343 		vchiq_platform_resume(state);
2344 
2345 out:
2346 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2347 	return;
2348 
2349 }
2350 #endif
2351 
2352 
2353 
2354 VCHIQ_STATUS_T
vchiq_use_internal(VCHIQ_STATE_T * state,VCHIQ_SERVICE_T * service,enum USE_TYPE_E use_type)2355 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2356 		enum USE_TYPE_E use_type)
2357 {
2358 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2359 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2360 	char entity[16];
2361 	int *entity_uc;
2362 	int local_uc, local_entity_uc;
2363 
2364 	if (!arm_state)
2365 		goto out;
2366 
2367 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2368 
2369 	if (use_type == USE_TYPE_VCHIQ) {
2370 		snprintf(entity, sizeof(entity), "VCHIQ:   ");
2371 		entity_uc = &arm_state->peer_use_count;
2372 	} else if (service) {
2373 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2374 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2375 			service->client_id);
2376 		entity_uc = &service->service_use_count;
2377 	} else {
2378 		vchiq_log_error(vchiq_susp_log_level, "%s null service "
2379 				"ptr", __func__);
2380 		ret = VCHIQ_ERROR;
2381 		goto out;
2382 	}
2383 
2384 	write_lock_bh(&arm_state->susp_res_lock);
2385 	while (arm_state->resume_blocked) {
2386 		/* If we call 'use' while force suspend is waiting for suspend,
2387 		 * then we're about to block the thread which the force is
2388 		 * waiting to complete, so we're bound to just time out. In this
2389 		 * case, set the suspend state such that the wait will be
2390 		 * canceled, so we can complete as quickly as possible. */
2391 		if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2392 				VC_SUSPEND_IDLE) {
2393 			set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2394 			break;
2395 		}
2396 		/* If suspend is already in progress then we need to block */
2397 		if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2398 			/* Indicate that there are threads waiting on the resume
2399 			 * blocker.  These need to be allowed to complete before
2400 			 * a _second_ call to force suspend can complete,
2401 			 * otherwise low priority threads might never actually
2402 			 * continue */
2403 			arm_state->blocked_count++;
2404 			write_unlock_bh(&arm_state->susp_res_lock);
2405 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2406 				"blocked - waiting...", __func__, entity);
2407 			if (wait_for_completion_killable(
2408 					&arm_state->resume_blocker) != 0) {
2409 				vchiq_log_error(vchiq_susp_log_level, "%s %s "
2410 					"wait for resume blocker interrupted",
2411 					__func__, entity);
2412 				ret = VCHIQ_ERROR;
2413 				write_lock_bh(&arm_state->susp_res_lock);
2414 				arm_state->blocked_count--;
2415 				write_unlock_bh(&arm_state->susp_res_lock);
2416 				goto out;
2417 			}
2418 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2419 				"unblocked", __func__, entity);
2420 			write_lock_bh(&arm_state->susp_res_lock);
2421 			if (--arm_state->blocked_count == 0)
2422 				complete_all(&arm_state->blocked_blocker);
2423 		}
2424 	}
2425 
2426 	stop_suspend_timer(arm_state);
2427 
2428 	local_uc = ++arm_state->videocore_use_count;
2429 	local_entity_uc = ++(*entity_uc);
2430 
2431 	/* If there's a pending request which hasn't yet been serviced then
2432 	 * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2433 	 * vc_resume_complete will block until we either resume or fail to
2434 	 * suspend */
2435 	if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2436 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2437 
2438 	if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2439 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2440 		vchiq_log_info(vchiq_susp_log_level,
2441 			"%s %s count %d, state count %d",
2442 			__func__, entity, local_entity_uc, local_uc);
2443 		request_poll(state, NULL, 0);
2444 	} else
2445 		vchiq_log_trace(vchiq_susp_log_level,
2446 			"%s %s count %d, state count %d",
2447 			__func__, entity, *entity_uc, local_uc);
2448 
2449 
2450 	write_unlock_bh(&arm_state->susp_res_lock);
2451 
2452 	/* Completion is in a done state when we're not suspended, so this won't
2453 	 * block for the non-suspended case. */
2454 	if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2455 		vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2456 			__func__, entity);
2457 		if (wait_for_completion_killable(
2458 				&arm_state->vc_resume_complete) != 0) {
2459 			vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2460 				"resume interrupted", __func__, entity);
2461 			ret = VCHIQ_ERROR;
2462 			goto out;
2463 		}
2464 		vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2465 			entity);
2466 	}
2467 
2468 	if (ret == VCHIQ_SUCCESS) {
2469 		VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2470 		long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2471 		while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2472 			/* Send the use notify to videocore */
2473 			status = vchiq_send_remote_use_active(state);
2474 			if (status == VCHIQ_SUCCESS)
2475 				ack_cnt--;
2476 			else
2477 				atomic_add(ack_cnt,
2478 					&arm_state->ka_use_ack_count);
2479 		}
2480 	}
2481 
2482 out:
2483 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2484 	return ret;
2485 }
2486 
2487 VCHIQ_STATUS_T
vchiq_release_internal(VCHIQ_STATE_T * state,VCHIQ_SERVICE_T * service)2488 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2489 {
2490 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2491 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2492 	char entity[16];
2493 	int *entity_uc;
2494 
2495 	if (!arm_state)
2496 		goto out;
2497 
2498 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2499 
2500 	if (service) {
2501 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2502 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2503 			service->client_id);
2504 		entity_uc = &service->service_use_count;
2505 	} else {
2506 		snprintf(entity, sizeof(entity), "PEER:   ");
2507 		entity_uc = &arm_state->peer_use_count;
2508 	}
2509 
2510 	write_lock_bh(&arm_state->susp_res_lock);
2511 	if (!arm_state->videocore_use_count || !(*entity_uc)) {
2512 		/* Don't use BUG_ON - don't allow user thread to crash kernel */
2513 		WARN_ON(!arm_state->videocore_use_count);
2514 		WARN_ON(!(*entity_uc));
2515 		ret = VCHIQ_ERROR;
2516 		goto unlock;
2517 	}
2518 	--arm_state->videocore_use_count;
2519 	--(*entity_uc);
2520 
2521 	if (!vchiq_videocore_wanted(state)) {
2522 		if (vchiq_platform_use_suspend_timer() &&
2523 				!arm_state->resume_blocked) {
2524 			/* Only use the timer if we're not trying to force
2525 			 * suspend (=> resume_blocked) */
2526 			start_suspend_timer(arm_state);
2527 		} else {
2528 			vchiq_log_info(vchiq_susp_log_level,
2529 				"%s %s count %d, state count %d - suspending",
2530 				__func__, entity, *entity_uc,
2531 				arm_state->videocore_use_count);
2532 			vchiq_arm_vcsuspend(state);
2533 		}
2534 	} else
2535 		vchiq_log_trace(vchiq_susp_log_level,
2536 			"%s %s count %d, state count %d",
2537 			__func__, entity, *entity_uc,
2538 			arm_state->videocore_use_count);
2539 
2540 unlock:
2541 	write_unlock_bh(&arm_state->susp_res_lock);
2542 
2543 out:
2544 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2545 	return ret;
2546 }
2547 
2548 void
vchiq_on_remote_use(VCHIQ_STATE_T * state)2549 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2550 {
2551 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2552 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2553 	atomic_inc(&arm_state->ka_use_count);
2554 	complete(&arm_state->ka_evt);
2555 }
2556 
2557 void
vchiq_on_remote_release(VCHIQ_STATE_T * state)2558 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2559 {
2560 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2561 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2562 	atomic_inc(&arm_state->ka_release_count);
2563 	complete(&arm_state->ka_evt);
2564 }
2565 
2566 VCHIQ_STATUS_T
vchiq_use_service_internal(VCHIQ_SERVICE_T * service)2567 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2568 {
2569 	return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2570 }
2571 
2572 VCHIQ_STATUS_T
vchiq_release_service_internal(VCHIQ_SERVICE_T * service)2573 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2574 {
2575 	return vchiq_release_internal(service->state, service);
2576 }
2577 
2578 #ifdef notyet
2579 VCHIQ_DEBUGFS_NODE_T *
vchiq_instance_get_debugfs_node(VCHIQ_INSTANCE_T instance)2580 vchiq_instance_get_debugfs_node(VCHIQ_INSTANCE_T instance)
2581 {
2582 	return &instance->debugfs_node;
2583 }
2584 
2585 int
vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)2586 vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2587 {
2588 	VCHIQ_SERVICE_T *service;
2589 	int use_count = 0, i;
2590 	i = 0;
2591 	while ((service = next_service_by_instance(instance->state,
2592 		instance, &i)) != NULL) {
2593 		use_count += service->service_use_count;
2594 		unlock_service(service);
2595 	}
2596 	return use_count;
2597 }
2598 
2599 int
vchiq_instance_get_pid(VCHIQ_INSTANCE_T instance)2600 vchiq_instance_get_pid(VCHIQ_INSTANCE_T instance)
2601 {
2602 	return instance->pid;
2603 }
2604 
2605 int
vchiq_instance_get_trace(VCHIQ_INSTANCE_T instance)2606 vchiq_instance_get_trace(VCHIQ_INSTANCE_T instance)
2607 {
2608 	return instance->trace;
2609 }
2610 
2611 void
vchiq_instance_set_trace(VCHIQ_INSTANCE_T instance,int trace)2612 vchiq_instance_set_trace(VCHIQ_INSTANCE_T instance, int trace)
2613 {
2614 	VCHIQ_SERVICE_T *service;
2615 	int i;
2616 	i = 0;
2617 	while ((service = next_service_by_instance(instance->state,
2618 		instance, &i)) != NULL) {
2619 		service->trace = trace;
2620 		unlock_service(service);
2621 	}
2622 	instance->trace = (trace != 0);
2623 }
2624 #endif
2625 
suspend_timer_callback(unsigned long context)2626 static void suspend_timer_callback(unsigned long context)
2627 {
2628 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2629 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2630 	if (!arm_state)
2631 		goto out;
2632 	vchiq_log_info(vchiq_susp_log_level,
2633 		"%s - suspend timer expired - check suspend", __func__);
2634 	vchiq_check_suspend(state);
2635 out:
2636 	return;
2637 }
2638 
2639 VCHIQ_STATUS_T
vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)2640 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2641 {
2642 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2643 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2644 	if (service) {
2645 		ret = vchiq_use_internal(service->state, service,
2646 				USE_TYPE_SERVICE_NO_RESUME);
2647 		unlock_service(service);
2648 	}
2649 	return ret;
2650 }
2651 
2652 VCHIQ_STATUS_T
vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)2653 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2654 {
2655 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2656 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2657 	if (service) {
2658 		ret = vchiq_use_internal(service->state, service,
2659 				USE_TYPE_SERVICE);
2660 		unlock_service(service);
2661 	}
2662 	return ret;
2663 }
2664 
2665 VCHIQ_STATUS_T
vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)2666 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2667 {
2668 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2669 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2670 	if (service) {
2671 		ret = vchiq_release_internal(service->state, service);
2672 		unlock_service(service);
2673 	}
2674 	return ret;
2675 }
2676 
2677 void
vchiq_dump_service_use_state(VCHIQ_STATE_T * state)2678 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2679 {
2680 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2681 	int i, j = 0;
2682 	/* Only dump 64 services */
2683 #define local_max_services 64
2684 	/* If there's more than 64 services, only dump ones with
2685 	 * non-zero counts */
2686 	int only_nonzero = 0;
2687 	static const char *nz = "<-- preventing suspend";
2688 
2689 	enum vc_suspend_status vc_suspend_state;
2690 	enum vc_resume_status  vc_resume_state;
2691 	int peer_count;
2692 	int vc_use_count;
2693 	int active_services;
2694 	struct service_data_struct {
2695 		int fourcc;
2696 		int clientid;
2697 		int use_count;
2698 	} service_data[local_max_services];
2699 
2700 	if (!arm_state)
2701 		return;
2702 
2703 	read_lock_bh(&arm_state->susp_res_lock);
2704 	vc_suspend_state = arm_state->vc_suspend_state;
2705 	vc_resume_state  = arm_state->vc_resume_state;
2706 	peer_count = arm_state->peer_use_count;
2707 	vc_use_count = arm_state->videocore_use_count;
2708 	active_services = state->unused_service;
2709 	if (active_services > local_max_services)
2710 		only_nonzero = 1;
2711 
2712 	for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2713 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
2714 		if (!service_ptr)
2715 			continue;
2716 
2717 		if (only_nonzero && !service_ptr->service_use_count)
2718 			continue;
2719 
2720 		if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2721 			service_data[j].fourcc = service_ptr->base.fourcc;
2722 			service_data[j].clientid = service_ptr->client_id;
2723 			service_data[j++].use_count = service_ptr->
2724 							service_use_count;
2725 		}
2726 	}
2727 
2728 	read_unlock_bh(&arm_state->susp_res_lock);
2729 
2730 	vchiq_log_warning(vchiq_susp_log_level,
2731 		"-- Videcore suspend state: %s --",
2732 		suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2733 	vchiq_log_warning(vchiq_susp_log_level,
2734 		"-- Videcore resume state: %s --",
2735 		resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2736 
2737 	if (only_nonzero)
2738 		vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2739 			"services (%d).  Only dumping up to first %d services "
2740 			"with non-zero use-count", active_services,
2741 			local_max_services);
2742 
2743 	for (i = 0; i < j; i++) {
2744 		vchiq_log_warning(vchiq_susp_log_level,
2745 			"----- %c%c%c%c:%d service count %d %s",
2746 			VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2747 			service_data[i].clientid,
2748 			service_data[i].use_count,
2749 			service_data[i].use_count ? nz : "");
2750 	}
2751 	vchiq_log_warning(vchiq_susp_log_level,
2752 		"----- VCHIQ use count count %d", peer_count);
2753 	vchiq_log_warning(vchiq_susp_log_level,
2754 		"--- Overall vchiq instance use count %d", vc_use_count);
2755 
2756 	vchiq_dump_platform_use_state(state);
2757 }
2758 
2759 VCHIQ_STATUS_T
vchiq_check_service(VCHIQ_SERVICE_T * service)2760 vchiq_check_service(VCHIQ_SERVICE_T *service)
2761 {
2762 	VCHIQ_ARM_STATE_T *arm_state;
2763 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2764 
2765 	if (!service || !service->state)
2766 		goto out;
2767 
2768 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2769 
2770 	arm_state = vchiq_platform_get_arm_state(service->state);
2771 
2772 	read_lock_bh(&arm_state->susp_res_lock);
2773 	if (service->service_use_count)
2774 		ret = VCHIQ_SUCCESS;
2775 	read_unlock_bh(&arm_state->susp_res_lock);
2776 
2777 	if (ret == VCHIQ_ERROR) {
2778 		vchiq_log_error(vchiq_susp_log_level,
2779 			"%s ERROR - %c%c%c%c:%8x service count %d, "
2780 			"state count %d, videocore suspend state %s", __func__,
2781 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2782 			service->client_id, service->service_use_count,
2783 			arm_state->videocore_use_count,
2784 			suspend_state_names[arm_state->vc_suspend_state +
2785 						VC_SUSPEND_NUM_OFFSET]);
2786 		vchiq_dump_service_use_state(service->state);
2787 	}
2788 out:
2789 	return ret;
2790 }
2791 
2792 /* stub functions */
vchiq_on_remote_use_active(VCHIQ_STATE_T * state)2793 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2794 {
2795 	(void)state;
2796 }
2797 
vchiq_platform_conn_state_changed(VCHIQ_STATE_T * state,VCHIQ_CONNSTATE_T oldstate,VCHIQ_CONNSTATE_T newstate)2798 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2799 	VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2800 {
2801 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2802 	vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2803 		get_conn_state_name(oldstate), get_conn_state_name(newstate));
2804 	if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2805 		write_lock_bh(&arm_state->susp_res_lock);
2806 		if (!arm_state->first_connect) {
2807 			char threadname[10];
2808 			arm_state->first_connect = 1;
2809 			write_unlock_bh(&arm_state->susp_res_lock);
2810 			snprintf(threadname, sizeof(threadname), "VCHIQka-%d",
2811 				state->id);
2812 			arm_state->ka_thread = vchiq_thread_create(
2813 				&vchiq_keepalive_thread_func,
2814 				(void *)state,
2815 				threadname);
2816 			if (arm_state->ka_thread == NULL) {
2817 				vchiq_log_error(vchiq_susp_log_level,
2818 					"vchiq: FATAL: couldn't create thread %s",
2819 					threadname);
2820 			} else {
2821 				wake_up_process(arm_state->ka_thread);
2822 			}
2823 		} else
2824 			write_unlock_bh(&arm_state->susp_res_lock);
2825 	}
2826 }
2827 
2828 
2829 /****************************************************************************
2830 *
2831 *   vchiq_init - called when the module is loaded.
2832 *
2833 ***************************************************************************/
2834 
2835 int __init vchiq_init(void);
2836 int __init
vchiq_init(void)2837 vchiq_init(void)
2838 {
2839 	int err;
2840 
2841 #ifdef notyet
2842 	/* create proc entries */
2843 	err = vchiq_proc_init();
2844 	if (err != 0)
2845 		goto failed_proc_init;
2846 #endif
2847 
2848 	spin_lock_init(&msg_queue_spinlock);
2849 
2850 	err = vchiq_platform_init(&g_state);
2851 	if (err != 0)
2852 		goto failed_platform_init;
2853 
2854 	vchiq_log_info(vchiq_arm_log_level,
2855 		"vchiq: initialised - version %d (min %d)",
2856 		VCHIQ_VERSION, VCHIQ_VERSION_MIN);
2857 
2858 	return 0;
2859 
2860 failed_platform_init:
2861 	vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2862 	return err;
2863 }
2864 
2865 /****************************************************************************
2866 *
2867 *   vchiq_exit - called when the module is unloaded.
2868 *
2869 ***************************************************************************/
2870 
2871 void vchiq_exit(void);
2872 void
vchiq_exit(void)2873 vchiq_exit(void)
2874 {
2875 	vchiq_platform_exit(&g_state);
2876 }
2877