xref: /netbsd-src/sys/external/bsd/vchiq/dist/interface/vchiq_arm/vchiq_arm.c (revision 80d9064ac03cbb6a4174695f0d5b237c8766d3d0)
1 /**
2  * Copyright (c) 2010-2012 Broadcom. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions, and the following disclaimer,
9  *    without modification.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The names of the above-listed copyright holders may not be used
14  *    to endorse or promote products derived from this software without
15  *    specific prior written permission.
16  *
17  * ALTERNATIVELY, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2, as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
22  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
25  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
28  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #include <sys/systm.h>
36 #include <sys/device.h>
37 #include <sys/file.h>
38 #include <sys/filedesc.h>
39 
40 #include "vchiq_core.h"
41 #include "vchiq_ioctl.h"
42 #include "vchiq_arm.h"
43 
44 #define DEVICE_NAME "vchiq"
45 
46 /* Override the default prefix, which would be vchiq_arm (from the filename) */
47 #undef MODULE_PARAM_PREFIX
48 #define MODULE_PARAM_PREFIX DEVICE_NAME "."
49 
50 #define VCHIQ_MINOR 0
51 
52 /* Some per-instance constants */
53 #define MAX_COMPLETIONS 16
54 #define MAX_SERVICES 64
55 #define MAX_ELEMENTS 8
56 #define MSG_QUEUE_SIZE 64
57 
58 #define KEEPALIVE_VER 1
59 #define KEEPALIVE_VER_MIN KEEPALIVE_VER
60 
61 MALLOC_DEFINE(M_VCHIQ, "vchiq_cdev", "VideoCore cdev memory");
62 
63 /* Run time control of log level, based on KERN_XXX level. */
64 int vchiq_arm_log_level = VCHIQ_LOG_DEFAULT;
65 int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
66 
67 #define SUSPEND_TIMER_TIMEOUT_MS 100
68 #define SUSPEND_RETRY_TIMER_TIMEOUT_MS 1000
69 
70 #define VC_SUSPEND_NUM_OFFSET 3 /* number of values before idle which are -ve */
71 static const char *const suspend_state_names[] = {
72 	"VC_SUSPEND_FORCE_CANCELED",
73 	"VC_SUSPEND_REJECTED",
74 	"VC_SUSPEND_FAILED",
75 	"VC_SUSPEND_IDLE",
76 	"VC_SUSPEND_REQUESTED",
77 	"VC_SUSPEND_IN_PROGRESS",
78 	"VC_SUSPEND_SUSPENDED"
79 };
80 #define VC_RESUME_NUM_OFFSET 1 /* number of values before idle which are -ve */
81 static const char *const resume_state_names[] = {
82 	"VC_RESUME_FAILED",
83 	"VC_RESUME_IDLE",
84 	"VC_RESUME_REQUESTED",
85 	"VC_RESUME_IN_PROGRESS",
86 	"VC_RESUME_RESUMED"
87 };
88 /* The number of times we allow force suspend to timeout before actually
89 ** _forcing_ suspend.  This is to cater for SW which fails to release vchiq
90 ** correctly - we don't want to prevent ARM suspend indefinitely in this case.
91 */
92 #define FORCE_SUSPEND_FAIL_MAX 8
93 
94 /* The time in ms allowed for videocore to go idle when force suspend has been
95  * requested */
96 #define FORCE_SUSPEND_TIMEOUT_MS 200
97 
98 
99 static void suspend_timer_callback(unsigned long context);
100 #ifdef notyet
101 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance);
102 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance);
103 #endif
104 
105 
106 typedef struct user_service_struct {
107 	VCHIQ_SERVICE_T *service;
108 	void *userdata;
109 	VCHIQ_INSTANCE_T instance;
110 	int is_vchi;
111 	int dequeue_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 	VCHIQ_HEADER_T * msg_queue[MSG_QUEUE_SIZE];
118 } USER_SERVICE_T;
119 
120 struct bulk_waiter_node {
121 	struct bulk_waiter bulk_waiter;
122 	struct lwp *l;
123 	struct list_head list;
124 };
125 
126 struct vchiq_instance_struct {
127 	VCHIQ_STATE_T *state;
128 	VCHIQ_COMPLETION_DATA_T completions[MAX_COMPLETIONS];
129 	int completion_insert;
130 	int completion_remove;
131 	struct semaphore insert_event;
132 	struct semaphore remove_event;
133 	struct mutex completion_mutex;
134 
135 	int connected;
136 	int closing;
137 	struct lwp *l;
138 	int mark;
139 
140 	struct list_head bulk_waiter_list;
141 	struct mutex bulk_waiter_list_mutex;
142 
143 	struct proc_dir_entry *proc_entry;
144 };
145 
146 typedef struct dump_context_struct {
147 	char __user *buf;
148 	size_t actual;
149 	size_t space;
150 	loff_t offset;
151 } DUMP_CONTEXT_T;
152 
153 VCHIQ_STATE_T g_state;
154 static DEFINE_SPINLOCK(msg_queue_spinlock);
155 
156 static const char *const ioctl_names[] = {
157 	"CONNECT",
158 	"SHUTDOWN",
159 	"CREATE_SERVICE",
160 	"REMOVE_SERVICE",
161 	"QUEUE_MESSAGE",
162 	"QUEUE_BULK_TRANSMIT",
163 	"QUEUE_BULK_RECEIVE",
164 	"AWAIT_COMPLETION",
165 	"DEQUEUE_MESSAGE",
166 	"GET_CLIENT_ID",
167 	"GET_CONFIG",
168 	"CLOSE_SERVICE",
169 	"USE_SERVICE",
170 	"RELEASE_SERVICE",
171 	"SET_SERVICE_OPTION",
172 	"DUMP_PHYS_MEM"
173 };
174 
175 vchiq_static_assert((sizeof(ioctl_names)/sizeof(ioctl_names[0])) ==
176 	(VCHIQ_IOC_MAX + 1));
177 
178 static dev_type_open(vchiq_open);
179 
180 struct cdevsw vchiq_cdevsw = {
181 	.d_open = vchiq_open,
182 	.d_close = noclose,
183 	.d_read = noread,
184 	.d_write = nowrite,
185 	.d_ioctl = noioctl,
186 	.d_stop = nostop,
187 	.d_tty = notty,
188 	.d_poll = nopoll,
189 	.d_mmap = nommap,
190 	.d_kqfilter = nokqfilter,
191 	.d_discard = nodiscard,
192 	.d_flag = D_OTHER | D_MPSAFE
193 };
194 
195 extern struct cfdriver vchiq_cd;
196 
197 static int	vchiq_ioctl(struct file *, u_long, void *);
198 static int	vchiq_close(struct file *);
199 
200 static const struct fileops vchiq_fileops = {
201 	.fo_read = fbadop_read,
202 	.fo_write = fbadop_write,
203 	.fo_ioctl = vchiq_ioctl,
204 	.fo_fcntl = fnullop_fcntl,
205 	.fo_poll = fnullop_poll,
206 	.fo_stat = fbadop_stat,
207 	.fo_close = vchiq_close,
208 	.fo_kqfilter = fnullop_kqfilter,
209 };
210 
211 #if 0
212 static void
213 dump_phys_mem(void *virt_addr, uint32_t num_bytes);
214 #endif
215 
216 /****************************************************************************
217 *
218 *   add_completion
219 *
220 ***************************************************************************/
221 
222 static VCHIQ_STATUS_T
223 add_completion(VCHIQ_INSTANCE_T instance, VCHIQ_REASON_T reason,
224 	VCHIQ_HEADER_T *header, USER_SERVICE_T *user_service,
225 	void *bulk_userdata)
226 {
227 	VCHIQ_COMPLETION_DATA_T *completion;
228 	DEBUG_INITIALISE(g_state.local)
229 
230 	while (instance->completion_insert ==
231 		(instance->completion_remove + MAX_COMPLETIONS)) {
232 		/* Out of space - wait for the client */
233 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
234 		vchiq_log_trace(vchiq_arm_log_level,
235 			"add_completion - completion queue full");
236 		DEBUG_COUNT(COMPLETION_QUEUE_FULL_COUNT);
237 		if (down_interruptible(&instance->remove_event) != 0) {
238 			vchiq_log_info(vchiq_arm_log_level,
239 				"service_callback interrupted");
240 			return VCHIQ_RETRY;
241 		} else if (instance->closing) {
242 			vchiq_log_info(vchiq_arm_log_level,
243 				"service_callback closing");
244 			return VCHIQ_ERROR;
245 		}
246 		DEBUG_TRACE(SERVICE_CALLBACK_LINE);
247 	}
248 
249 	completion =
250 		 &instance->completions[instance->completion_insert &
251 		 (MAX_COMPLETIONS - 1)];
252 
253 	completion->header = header;
254 	completion->reason = reason;
255 	/* N.B. service_userdata is updated while processing AWAIT_COMPLETION */
256 	completion->service_userdata = user_service->service;
257 	completion->bulk_userdata = bulk_userdata;
258 
259 	if (reason == VCHIQ_SERVICE_CLOSED)
260 		/* Take an extra reference, to be held until
261 		   this CLOSED notification is delivered. */
262 		lock_service(user_service->service);
263 
264 	/* A write barrier is needed here to ensure that the entire completion
265 		record is written out before the insert point. */
266 	wmb();
267 
268 	if (reason == VCHIQ_MESSAGE_AVAILABLE)
269 		user_service->message_available_pos =
270 			instance->completion_insert;
271 	instance->completion_insert++;
272 
273 	up(&instance->insert_event);
274 
275 	return VCHIQ_SUCCESS;
276 }
277 
278 /****************************************************************************
279 *
280 *   service_callback
281 *
282 ***************************************************************************/
283 
284 static VCHIQ_STATUS_T
285 service_callback(VCHIQ_REASON_T reason, VCHIQ_HEADER_T *header,
286 	VCHIQ_SERVICE_HANDLE_T handle, void *bulk_userdata)
287 {
288 	/* How do we ensure the callback goes to the right client?
289 	** The service_user data points to a USER_SERVICE_T record containing
290 	** the original callback and the user state structure, which contains a
291 	** circular buffer for completion records.
292 	*/
293 	USER_SERVICE_T *user_service;
294 	VCHIQ_SERVICE_T *service;
295 	VCHIQ_INSTANCE_T instance;
296 	DEBUG_INITIALISE(g_state.local)
297 
298 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
299 
300 	service = handle_to_service(handle);
301 	BUG_ON(!service);
302 	user_service = (USER_SERVICE_T *)service->base.userdata;
303 	instance = user_service->instance;
304 
305 	if (!instance || instance->closing)
306 		return VCHIQ_SUCCESS;
307 
308 	vchiq_log_trace(vchiq_arm_log_level,
309 		"service_callback - service %lx(%d), handle %x, reason %d, header %lx, "
310 		"instance %lx, bulk_userdata %lx",
311 		(unsigned long)user_service,
312 		service->localport, service->handle,
313 		reason, (unsigned long)header,
314 		(unsigned long)instance, (unsigned long)bulk_userdata);
315 
316 	if (header && user_service->is_vchi) {
317 		spin_lock(&msg_queue_spinlock);
318 		while (user_service->msg_insert ==
319 			(user_service->msg_remove + MSG_QUEUE_SIZE)) {
320 			spin_unlock(&msg_queue_spinlock);
321 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
322 			DEBUG_COUNT(MSG_QUEUE_FULL_COUNT);
323 			vchiq_log_trace(vchiq_arm_log_level,
324 				"service_callback - msg queue full");
325 			/* If there is no MESSAGE_AVAILABLE in the completion
326 			** queue, add one
327 			*/
328 			if ((user_service->message_available_pos -
329 				instance->completion_remove) < 0) {
330 				VCHIQ_STATUS_T status;
331 				vchiq_log_info(vchiq_arm_log_level,
332 					"Inserting extra MESSAGE_AVAILABLE");
333 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
334 				status = add_completion(instance, reason,
335 					NULL, user_service, bulk_userdata);
336 				if (status != VCHIQ_SUCCESS) {
337 					DEBUG_TRACE(SERVICE_CALLBACK_LINE);
338 					return status;
339 				}
340 			}
341 
342 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
343 			if (down_interruptible(&user_service->remove_event)
344 				!= 0) {
345 				vchiq_log_info(vchiq_arm_log_level,
346 					"service_callback interrupted");
347 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
348 				return VCHIQ_RETRY;
349 			} else if (instance->closing) {
350 				vchiq_log_info(vchiq_arm_log_level,
351 					"service_callback closing");
352 				DEBUG_TRACE(SERVICE_CALLBACK_LINE);
353 				return VCHIQ_ERROR;
354 			}
355 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
356 			spin_lock(&msg_queue_spinlock);
357 		}
358 
359 		user_service->msg_queue[user_service->msg_insert &
360 			(MSG_QUEUE_SIZE - 1)] = header;
361 		user_service->msg_insert++;
362 		spin_unlock(&msg_queue_spinlock);
363 
364 		up(&user_service->insert_event);
365 
366 		/* If there is a thread waiting in DEQUEUE_MESSAGE, or if
367 		** there is a MESSAGE_AVAILABLE in the completion queue then
368 		** bypass the completion queue.
369 		*/
370 		if (((user_service->message_available_pos -
371 			instance->completion_remove) >= 0) ||
372 			user_service->dequeue_pending) {
373 			DEBUG_TRACE(SERVICE_CALLBACK_LINE);
374 			user_service->dequeue_pending = 0;
375 			return VCHIQ_SUCCESS;
376 		}
377 
378 		header = NULL;
379 	}
380 	DEBUG_TRACE(SERVICE_CALLBACK_LINE);
381 
382 	return add_completion(instance, reason, header, user_service,
383 		bulk_userdata);
384 }
385 
386 /****************************************************************************
387 *
388 *   user_service_free
389 *
390 ***************************************************************************/
391 static void
392 user_service_free(void *userdata)
393 {
394 	USER_SERVICE_T *user_service = userdata;
395 
396 	_sema_destroy(&user_service->insert_event);
397 	_sema_destroy(&user_service->remove_event);
398 
399 	kfree(user_service);
400 }
401 
402 /****************************************************************************
403 *
404 *   vchiq_ioctl
405 *
406 ***************************************************************************/
407 
408 static int
409 vchiq_ioctl(struct file *fp, u_long cmd, void *arg)
410 {
411 	VCHIQ_INSTANCE_T instance;
412 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
413 	VCHIQ_SERVICE_T *service = NULL;
414 	int ret = 0;
415 	int i, rc;
416 	DEBUG_INITIALISE(g_state.local)
417 
418 	instance = fp->f_data;
419 
420 /* XXXBSD: HACK! */
421 #define _IOC_NR(x) ((x) & 0xff)
422 #define	_IOC_TYPE(x)	IOCGROUP(x)
423 
424 	vchiq_log_trace(vchiq_arm_log_level,
425 		 "vchiq_ioctl - instance %x, cmd %s, arg %p",
426 		(unsigned int)instance,
427 		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
428 		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
429 		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
430 
431 	switch (cmd) {
432 	case VCHIQ_IOC_SHUTDOWN:
433 		if (!instance->connected)
434 			break;
435 
436 		/* Remove all services */
437 		i = 0;
438 		while ((service = next_service_by_instance(instance->state,
439 			instance, &i)) != NULL) {
440 			status = vchiq_remove_service(service->handle);
441 			unlock_service(service);
442 			if (status != VCHIQ_SUCCESS)
443 				break;
444 		}
445 		service = NULL;
446 
447 		if (status == VCHIQ_SUCCESS) {
448 			/* Wake the completion thread and ask it to exit */
449 			instance->closing = 1;
450 			up(&instance->insert_event);
451 		}
452 
453 		break;
454 
455 	case VCHIQ_IOC_CONNECT:
456 		if (instance->connected) {
457 			ret = -EINVAL;
458 			break;
459 		}
460 		rc = lmutex_lock_interruptible(&instance->state->mutex);
461 		if (rc != 0) {
462 			vchiq_log_error(vchiq_arm_log_level,
463 				"vchiq: connect: could not lock mutex for "
464 				"state %d: %d",
465 				instance->state->id, rc);
466 			ret = -EINTR;
467 			break;
468 		}
469 		status = vchiq_connect_internal(instance->state, instance);
470 		lmutex_unlock(&instance->state->mutex);
471 
472 		if (status == VCHIQ_SUCCESS)
473 			instance->connected = 1;
474 		else
475 			vchiq_log_error(vchiq_arm_log_level,
476 				"vchiq: could not connect: %d", status);
477 		break;
478 
479 	case VCHIQ_IOC_CREATE_SERVICE: {
480 		VCHIQ_CREATE_SERVICE_T *pargs = arg;
481 		USER_SERVICE_T *user_service = NULL;
482 		void *userdata;
483 		int srvstate;
484 
485 		user_service = kzalloc(sizeof(USER_SERVICE_T), GFP_KERNEL);
486 		if (!user_service) {
487 			ret = -ENOMEM;
488 			break;
489 		}
490 
491 		if (pargs->is_open) {
492 			if (!instance->connected) {
493 				ret = -ENOTCONN;
494 				kfree(user_service);
495 				break;
496 			}
497 			srvstate = VCHIQ_SRVSTATE_OPENING;
498 		} else {
499 			srvstate =
500 				 instance->connected ?
501 				 VCHIQ_SRVSTATE_LISTENING :
502 				 VCHIQ_SRVSTATE_HIDDEN;
503 		}
504 
505 		userdata = pargs->params.userdata;
506 		pargs->params.callback = service_callback;
507 		pargs->params.userdata = user_service;
508 		service = vchiq_add_service_internal(
509 				instance->state,
510 				&pargs->params, srvstate,
511 				instance, user_service_free);
512 
513 		if (service != NULL) {
514 			user_service->service = service;
515 			user_service->userdata = userdata;
516 			user_service->instance = instance;
517 			user_service->is_vchi = pargs->is_vchi;
518 			user_service->dequeue_pending = 0;
519 			user_service->message_available_pos =
520 				instance->completion_remove - 1;
521 			user_service->msg_insert = 0;
522 			user_service->msg_remove = 0;
523 			_sema_init(&user_service->insert_event, 0);
524 			_sema_init(&user_service->remove_event, 0);
525 
526 			if (pargs->is_open) {
527 				status = vchiq_open_service_internal
528 					(service, (uintptr_t)instance->l);
529 				if (status != VCHIQ_SUCCESS) {
530 					vchiq_remove_service(service->handle);
531 					service = NULL;
532 					ret = (status == VCHIQ_RETRY) ?
533 						-EINTR : -EIO;
534 					break;
535 				}
536 			}
537 
538 #ifdef VCHIQ_IOCTL_DEBUG
539 			printf("%s: [CREATE SERVICE] handle = %08x\n", __func__, service->handle);
540 #endif
541 			pargs->handle = service->handle;
542 
543 			service = NULL;
544 		} else {
545 			ret = -EEXIST;
546 			kfree(user_service);
547 		}
548 	} break;
549 
550 	case VCHIQ_IOC_CLOSE_SERVICE: {
551 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
552 
553 #ifdef VCHIQ_IOCTL_DEBUG
554 		printf("%s: [CLOSE SERVICE] handle = %08x\n", __func__, handle);
555 #endif
556 
557 		service = find_service_for_instance(instance, handle);
558 		if (service != NULL)
559 			status = vchiq_close_service(service->handle);
560 		else
561 			ret = -EINVAL;
562 	} break;
563 
564 	case VCHIQ_IOC_REMOVE_SERVICE: {
565 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
566 
567 #ifdef VCHIQ_IOCTL_DEBUG
568 		printf("%s: [REMOVE SERVICE] handle = %08x\n", __func__, handle);
569 #endif
570 
571 		service = find_service_for_instance(instance, handle);
572 		if (service != NULL)
573 			status = vchiq_remove_service(service->handle);
574 		else
575 			ret = -EINVAL;
576 	} break;
577 
578 	case VCHIQ_IOC_USE_SERVICE:
579 	case VCHIQ_IOC_RELEASE_SERVICE:	{
580 		VCHIQ_SERVICE_HANDLE_T handle = *(VCHIQ_SERVICE_HANDLE_T *)arg;
581 
582 #ifdef VCHIQ_IOCTL_DEBUG
583 		printf("%s: [%s SERVICE] handle = %08x\n", __func__,
584 		    cmd == VCHIQ_IOC_USE_SERVICE ? "USE" : "RELEASE", handle);
585 #endif
586 
587 		service = find_service_for_instance(instance, handle);
588 		if (service != NULL) {
589 			status = (cmd == VCHIQ_IOC_USE_SERVICE)	?
590 				vchiq_use_service_internal(service) :
591 				vchiq_release_service_internal(service);
592 			if (status != VCHIQ_SUCCESS) {
593 				vchiq_log_error(vchiq_susp_log_level,
594 					"%s: cmd %s returned error %d for "
595 					"service %c%c%c%c:%8x",
596 					__func__,
597 					(cmd == VCHIQ_IOC_USE_SERVICE) ?
598 						"VCHIQ_IOC_USE_SERVICE" :
599 						"VCHIQ_IOC_RELEASE_SERVICE",
600 					status,
601 					VCHIQ_FOURCC_AS_4CHARS(
602 						service->base.fourcc),
603 					service->client_id);
604 				ret = -EINVAL;
605 			}
606 		} else
607 			ret = -EINVAL;
608 	} break;
609 
610 	case VCHIQ_IOC_QUEUE_MESSAGE: {
611 		VCHIQ_QUEUE_MESSAGE_T *pargs = arg;
612 
613 #ifdef VCHIQ_IOCTL_DEBUG
614 		printf("%s: [QUEUE MESSAGE] handle = %08x\n", __func__, pargs->handle);
615 #endif
616 
617 		service = find_service_for_instance(instance, pargs->handle);
618 
619 		if ((service != NULL) && (pargs->count <= MAX_ELEMENTS)) {
620 			/* Copy elements into kernel space */
621 			VCHIQ_ELEMENT_T elements[MAX_ELEMENTS];
622 			if (copy_from_user(elements, pargs->elements,
623 				pargs->count * sizeof(VCHIQ_ELEMENT_T)) == 0)
624 				status = vchiq_queue_message
625 					(pargs->handle,
626 					elements, pargs->count);
627 			else
628 				ret = -EFAULT;
629 		} else {
630 			ret = -EINVAL;
631 		}
632 	} break;
633 
634 	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
635 	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
636 		VCHIQ_QUEUE_BULK_TRANSFER_T *pargs = arg;
637 		struct bulk_waiter_node *waiter = NULL;
638 		VCHIQ_BULK_DIR_T dir =
639 			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
640 			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
641 
642 		service = find_service_for_instance(instance, pargs->handle);
643 		if (!service) {
644 			ret = -EINVAL;
645 			break;
646 		}
647 
648 		if (pargs->mode == VCHIQ_BULK_MODE_BLOCKING) {
649 			waiter = kzalloc(sizeof(struct bulk_waiter_node),
650 				GFP_KERNEL);
651 			if (!waiter) {
652 				ret = -ENOMEM;
653 				break;
654 			}
655 			pargs->userdata = &waiter->bulk_waiter;
656 		} else if (pargs->mode == VCHIQ_BULK_MODE_WAITING) {
657 			struct list_head *pos;
658 			lmutex_lock(&instance->bulk_waiter_list_mutex);
659 			list_for_each(pos, &instance->bulk_waiter_list) {
660 				if (list_entry(pos, struct bulk_waiter_node,
661 					list)->l == current) {
662 					waiter = list_entry(pos,
663 						struct bulk_waiter_node,
664 						list);
665 					list_del(pos);
666 					break;
667 				}
668 
669 			}
670 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
671 			if (!waiter) {
672 				vchiq_log_error(vchiq_arm_log_level,
673 					"no bulk_waiter found for lwp %p",
674 					current);
675 				ret = -ESRCH;
676 				break;
677 			}
678 			vchiq_log_info(vchiq_arm_log_level,
679 				"found bulk_waiter %x for lwp %p",
680 				(unsigned int)waiter, current);
681 			pargs->userdata = &waiter->bulk_waiter;
682 		}
683 		status = vchiq_bulk_transfer
684 			(pargs->handle,
685 			 VCHI_MEM_HANDLE_INVALID,
686 			 pargs->data, pargs->size,
687 			 pargs->userdata, pargs->mode,
688 			 dir);
689 		if (!waiter)
690 			break;
691 		if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
692 			!waiter->bulk_waiter.bulk) {
693 			if (waiter->bulk_waiter.bulk) {
694 				/* Cancel the signal when the transfer
695 				** completes. */
696 				spin_lock(&bulk_waiter_spinlock);
697 				waiter->bulk_waiter.bulk->userdata = NULL;
698 				spin_unlock(&bulk_waiter_spinlock);
699 			}
700 			_sema_destroy(&waiter->bulk_waiter.event);
701 			kfree(waiter);
702 		} else {
703 			const VCHIQ_BULK_MODE_T mode_waiting =
704 				VCHIQ_BULK_MODE_WAITING;
705 			waiter->l = current;
706 			lmutex_lock(&instance->bulk_waiter_list_mutex);
707 			list_add(&waiter->list, &instance->bulk_waiter_list);
708 			lmutex_unlock(&instance->bulk_waiter_list_mutex);
709 			vchiq_log_info(vchiq_arm_log_level,
710 				"saved bulk_waiter %x for lwp %p",
711 				(unsigned int)waiter, current);
712 
713 			pargs->mode = mode_waiting;
714 		}
715 	} break;
716 
717 	case VCHIQ_IOC_AWAIT_COMPLETION: {
718 		VCHIQ_AWAIT_COMPLETION_T *pargs = arg;
719 
720 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
721 		if (!instance->connected) {
722 			ret = -ENOTCONN;
723 			break;
724 		}
725 
726 		lmutex_lock(&instance->completion_mutex);
727 
728 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
729 		while ((instance->completion_remove ==
730 			instance->completion_insert)
731 			&& !instance->closing) {
732 			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
733 			lmutex_unlock(&instance->completion_mutex);
734 			rc = down_interruptible(&instance->insert_event);
735 			lmutex_lock(&instance->completion_mutex);
736 			if (rc != 0) {
737 				DEBUG_TRACE(AWAIT_COMPLETION_LINE);
738 				vchiq_log_info(vchiq_arm_log_level,
739 					"AWAIT_COMPLETION interrupted");
740 				ret = -EINTR;
741 				break;
742 			}
743 		}
744 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
745 
746 		/* A read memory barrier is needed to stop prefetch of a stale
747 		** completion record
748 		*/
749 		rmb();
750 
751 		if (ret == 0) {
752 			int msgbufcount = pargs->msgbufcount;
753 			int count;
754 
755 			for (count = 0; count < pargs->count; count++) {
756 				VCHIQ_COMPLETION_DATA_T *completion;
757 				VCHIQ_SERVICE_T *service1;
758 				USER_SERVICE_T *user_service;
759 				VCHIQ_HEADER_T *header;
760 				if (instance->completion_remove ==
761 					instance->completion_insert)
762 					break;
763 				completion = &instance->completions[
764 					instance->completion_remove &
765 					(MAX_COMPLETIONS - 1)];
766 
767 				service1 = completion->service_userdata;
768 				user_service = service1->base.userdata;
769 				completion->service_userdata =
770 					user_service->userdata;
771 
772 				header = completion->header;
773 				if (header) {
774 					void __user *msgbuf;
775 					int msglen;
776 
777 					msglen = header->size +
778 						sizeof(VCHIQ_HEADER_T);
779 					/* This must be a VCHIQ-style service */
780 					if (pargs->msgbufsize < msglen) {
781 						vchiq_log_error(
782 							vchiq_arm_log_level,
783 							"header %x: msgbufsize"
784 							" %x < msglen %x",
785 							(unsigned int)header,
786 							pargs->msgbufsize,
787 							msglen);
788 						WARN(1, "invalid message "
789 							"size\n");
790 						if (count == 0)
791 							ret = -EMSGSIZE;
792 						break;
793 					}
794 					if (msgbufcount <= 0)
795 						/* Stall here for lack of a
796 						** buffer for the message. */
797 						break;
798 					/* Get the pointer from user space */
799 					msgbufcount--;
800 					if (copy_from_user(&msgbuf,
801 						(const void __user *)
802 						&pargs->msgbufs[msgbufcount],
803 						sizeof(msgbuf)) != 0) {
804 						if (count == 0)
805 							ret = -EFAULT;
806 						break;
807 					}
808 
809 					/* Copy the message to user space */
810 					if (copy_to_user(msgbuf, header,
811 						msglen) != 0) {
812 						if (count == 0)
813 							ret = -EFAULT;
814 						break;
815 					}
816 
817 					/* Now it has been copied, the message
818 					** can be released. */
819 					vchiq_release_message(service1->handle,
820 						header);
821 
822 					/* The completion must point to the
823 					** msgbuf. */
824 					completion->header = msgbuf;
825 				}
826 
827 				if (completion->reason ==
828 					VCHIQ_SERVICE_CLOSED)
829 					unlock_service(service1);
830 
831 				if (copy_to_user((void __user *)(
832 					(size_t)pargs->buf +
833 					count * sizeof(VCHIQ_COMPLETION_DATA_T)),
834 					completion,
835 					sizeof(VCHIQ_COMPLETION_DATA_T)) != 0) {
836 						if (count == 0)
837 							ret = -EFAULT;
838 					break;
839 				}
840 
841 				instance->completion_remove++;
842 			}
843 
844 			pargs->msgbufcount = msgbufcount;
845 			pargs->count = count;
846 		}
847 
848 		if (ret != 0)
849 			up(&instance->remove_event);
850 		lmutex_unlock(&instance->completion_mutex);
851 		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
852 	} break;
853 
854 	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
855 		VCHIQ_DEQUEUE_MESSAGE_T *pargs = arg;
856 		USER_SERVICE_T *user_service;
857 		VCHIQ_HEADER_T *header;
858 
859 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
860 		service = find_service_for_instance(instance, pargs->handle);
861 		if (!service) {
862 			ret = -EINVAL;
863 			break;
864 		}
865 		user_service = (USER_SERVICE_T *)service->base.userdata;
866 		if (user_service->is_vchi == 0) {
867 			ret = -EINVAL;
868 			break;
869 		}
870 
871 		spin_lock(&msg_queue_spinlock);
872 		if (user_service->msg_remove == user_service->msg_insert) {
873 			if (!pargs->blocking) {
874 				spin_unlock(&msg_queue_spinlock);
875 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
876 				ret = -EWOULDBLOCK;
877 				break;
878 			}
879 			user_service->dequeue_pending = 1;
880 			do {
881 				spin_unlock(&msg_queue_spinlock);
882 				DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
883 				if (down_interruptible(
884 					&user_service->insert_event) != 0) {
885 					vchiq_log_info(vchiq_arm_log_level,
886 						"DEQUEUE_MESSAGE interrupted");
887 					ret = -EINTR;
888 					break;
889 				}
890 				spin_lock(&msg_queue_spinlock);
891 			} while (user_service->msg_remove ==
892 				user_service->msg_insert);
893 
894 			if (ret)
895 				break;
896 		}
897 
898 		BUG_ON((int)(user_service->msg_insert -
899 			user_service->msg_remove) < 0);
900 
901 		header = user_service->msg_queue[user_service->msg_remove &
902 			(MSG_QUEUE_SIZE - 1)];
903 		user_service->msg_remove++;
904 		spin_unlock(&msg_queue_spinlock);
905 
906 		up(&user_service->remove_event);
907 		if (header == NULL)
908 			ret = -ENOTCONN;
909 		else if (header->size <= pargs->bufsize) {
910 			/* Copy to user space if msgbuf is not NULL */
911 			if ((pargs->buf == NULL) ||
912 				(copy_to_user((void __user *)pargs->buf,
913 				header->data,
914 				header->size) == 0)) {
915 				pargs->bufsize = header->size;
916 				vchiq_release_message(
917 					service->handle,
918 					header);
919 			} else
920 				ret = -EFAULT;
921 		} else {
922 			vchiq_log_error(vchiq_arm_log_level,
923 				"header %x: bufsize %x < size %x",
924 				(unsigned int)header, pargs->bufsize,
925 				header->size);
926 			WARN(1, "invalid size\n");
927 			ret = -EMSGSIZE;
928 		}
929 		DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
930 	} break;
931 
932 	case VCHIQ_IOC_GET_CLIENT_ID: {
933 		VCHIQ_SERVICE_HANDLE_T handle = (VCHIQ_SERVICE_HANDLE_T)arg;
934 
935 		ret = vchiq_get_client_id(handle);
936 	} break;
937 
938 	case VCHIQ_IOC_GET_CONFIG: {
939 		VCHIQ_GET_CONFIG_T *pargs = arg;
940 		VCHIQ_CONFIG_T config;
941 
942 		if (pargs->config_size > sizeof(config)) {
943 			ret = -EINVAL;
944 			break;
945 		}
946 		status = vchiq_get_config(instance, pargs->config_size, &config);
947 		if (status == VCHIQ_SUCCESS) {
948 			if (copy_to_user((void __user *)pargs->pconfig,
949 				&config, pargs->config_size) != 0) {
950 				ret = -EFAULT;
951 				break;
952 			}
953 		}
954 	} break;
955 
956 	case VCHIQ_IOC_SET_SERVICE_OPTION: {
957 		VCHIQ_SET_SERVICE_OPTION_T *pargs = arg;
958 
959 		service = find_service_for_instance(instance, pargs->handle);
960 		if (!service) {
961 			ret = -EINVAL;
962 			break;
963 		}
964 
965 		status = vchiq_set_service_option(
966 				pargs->handle, pargs->option, pargs->value);
967 	} break;
968 
969 	case VCHIQ_IOC_DUMP_PHYS_MEM: {
970 #if 0
971 		VCHIQ_DUMP_MEM_T *pargs = arg;
972 #endif
973 
974 		printf("IMPLEMENT ME: %s:%d\n", __FILE__, __LINE__);
975 #if 0
976 		dump_phys_mem(pargs->virt_addr, pargs->num_bytes);
977 #endif
978 	} break;
979 
980 	default:
981 		ret = -ENOTTY;
982 		break;
983 	}
984 
985 	if (service)
986 		unlock_service(service);
987 
988 	if (ret == 0) {
989 		if (status == VCHIQ_ERROR)
990 			ret = -EIO;
991 		else if (status == VCHIQ_RETRY)
992 			ret = -EINTR;
993 	}
994 
995 	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
996 		(ret != -EWOULDBLOCK))
997 		vchiq_log_info(vchiq_arm_log_level,
998 			"  ioctl instance %lx, cmd %s -> status %d, %d",
999 			(unsigned long)instance,
1000 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1001 				ioctl_names[_IOC_NR(cmd)] :
1002 				"<invalid>",
1003 			status, ret);
1004 	else
1005 		vchiq_log_trace(vchiq_arm_log_level,
1006 			"  ioctl instance %lx, cmd %s -> status %d, %d",
1007 			(unsigned long)instance,
1008 			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
1009 				ioctl_names[_IOC_NR(cmd)] :
1010 				"<invalid>",
1011 			status, ret);
1012 
1013 	/* XXXBSD: report BSD-style error to userland */
1014 	if (ret < 0)
1015 		ret = -ret;
1016 
1017 	return ret;
1018 }
1019 
1020 #if notyet
1021 static void
1022 instance_dtr(void *data)
1023 {
1024 
1025    free(data, M_VCHIQ);
1026 }
1027 #endif
1028 
1029 /****************************************************************************
1030 *
1031 *   vchiq_open
1032 *
1033 ***************************************************************************/
1034 
1035 static int
1036 vchiq_open(dev_t dev, int flags, int mode, lwp_t *l)
1037 {
1038 	VCHIQ_INSTANCE_T instance = NULL;
1039 	struct file *fp;
1040 	int err, fd;
1041 
1042 	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
1043 
1044 	/* XXXBSD: do we really need this check? */
1045 	if (device_lookup_private(&vchiq_cd, minor(dev)) != NULL) {
1046 		VCHIQ_STATE_T *state = vchiq_get_state();
1047 
1048 		if (!state) {
1049 			vchiq_log_error(vchiq_arm_log_level,
1050 				"vchiq has no connection to VideoCore");
1051 			return -ENOTCONN;
1052 		}
1053 
1054 		instance = kzalloc(sizeof(*instance), GFP_KERNEL);
1055 		if (!instance)
1056 			return -ENOMEM;
1057 
1058 		err = fd_allocfile(&fp, &fd);
1059 		if (err) {
1060 			kfree(instance);
1061 			return -err;
1062 		}
1063 
1064 		instance->state = state;
1065 		instance->l = l;
1066 
1067 #ifdef notyet
1068 		ret = vchiq_proc_add_instance(instance);
1069 		if (ret != 0) {
1070 			kfree(instance);
1071 			return ret;
1072 		}
1073 #endif
1074 
1075 		_sema_init(&instance->insert_event, 0);
1076 		_sema_init(&instance->remove_event, 0);
1077 		lmutex_init(&instance->completion_mutex);
1078 		lmutex_init(&instance->bulk_waiter_list_mutex);
1079 		INIT_LIST_HEAD(&instance->bulk_waiter_list);
1080 
1081 	}
1082 	else {
1083 		vchiq_log_error(vchiq_arm_log_level,
1084 			"Unknown minor device");
1085 		return -ENXIO;
1086 	}
1087 
1088 	return fd_clone(fp, fd, flags, &vchiq_fileops, instance);
1089 }
1090 
1091 /****************************************************************************
1092 *
1093 *   vchiq_release
1094 *
1095 ***************************************************************************/
1096 
1097 static int
1098 vchiq_close(struct file *fp)
1099 {
1100 	int ret = 0;
1101 	if (1) {
1102 		VCHIQ_INSTANCE_T instance;
1103 		VCHIQ_STATE_T *state = vchiq_get_state();
1104 		VCHIQ_SERVICE_T *service;
1105 		int i;
1106 
1107 		instance = fp->f_data;
1108 
1109 		vchiq_log_info(vchiq_arm_log_level,
1110 			"vchiq_release: instance=%lx",
1111 			(unsigned long)instance);
1112 
1113 		if (!state) {
1114 			ret = -EPERM;
1115 			goto out;
1116 		}
1117 
1118 		/* Ensure videocore is awake to allow termination. */
1119 		vchiq_use_internal(instance->state, NULL,
1120 				USE_TYPE_VCHIQ);
1121 
1122 		lmutex_lock(&instance->completion_mutex);
1123 
1124 		/* Wake the completion thread and ask it to exit */
1125 		instance->closing = 1;
1126 		up(&instance->insert_event);
1127 
1128 		lmutex_unlock(&instance->completion_mutex);
1129 
1130 		/* Wake the slot handler if the completion queue is full. */
1131 		up(&instance->remove_event);
1132 
1133 		/* Mark all services for termination... */
1134 		i = 0;
1135 		while ((service = next_service_by_instance(state, instance,
1136 			&i)) !=	NULL) {
1137 			USER_SERVICE_T *user_service = service->base.userdata;
1138 
1139 			/* Wake the slot handler if the msg queue is full. */
1140 			up(&user_service->remove_event);
1141 
1142 			vchiq_terminate_service_internal(service);
1143 			unlock_service(service);
1144 		}
1145 
1146 		/* ...and wait for them to die */
1147 		i = 0;
1148 		while ((service = next_service_by_instance(state, instance, &i))
1149 			!= NULL) {
1150 			USER_SERVICE_T *user_service = service->base.userdata;
1151 
1152 			down(&service->remove_event);
1153 
1154 			BUG_ON(service->srvstate != VCHIQ_SRVSTATE_FREE);
1155 
1156 			spin_lock(&msg_queue_spinlock);
1157 
1158 			while (user_service->msg_remove !=
1159 				user_service->msg_insert) {
1160 				VCHIQ_HEADER_T *header = user_service->
1161 					msg_queue[user_service->msg_remove &
1162 						(MSG_QUEUE_SIZE - 1)];
1163 				user_service->msg_remove++;
1164 				spin_unlock(&msg_queue_spinlock);
1165 
1166 				if (header)
1167 					vchiq_release_message(
1168 						service->handle,
1169 						header);
1170 				spin_lock(&msg_queue_spinlock);
1171 			}
1172 
1173 			spin_unlock(&msg_queue_spinlock);
1174 
1175 			unlock_service(service);
1176 		}
1177 
1178 		/* Release any closed services */
1179 		while (instance->completion_remove !=
1180 			instance->completion_insert) {
1181 			VCHIQ_COMPLETION_DATA_T *completion;
1182 			VCHIQ_SERVICE_T *service1;
1183 			completion = &instance->completions[
1184 				instance->completion_remove &
1185 				(MAX_COMPLETIONS - 1)];
1186 			service1 = completion->service_userdata;
1187 			if (completion->reason == VCHIQ_SERVICE_CLOSED)
1188 				unlock_service(service1);
1189 			instance->completion_remove++;
1190 		}
1191 
1192 		/* Release the PEER service count. */
1193 		vchiq_release_internal(instance->state, NULL);
1194 
1195 		{
1196 			struct list_head *pos, *next;
1197 			list_for_each_safe(pos, next,
1198 				&instance->bulk_waiter_list) {
1199 				struct bulk_waiter_node *waiter;
1200 				waiter = list_entry(pos,
1201 					struct bulk_waiter_node,
1202 					list);
1203 				list_del(pos);
1204 				vchiq_log_info(vchiq_arm_log_level,
1205 					"bulk_waiter - cleaned up %x "
1206 					"for lwp %p",
1207 					(unsigned int)waiter, waiter->l);
1208 		                _sema_destroy(&waiter->bulk_waiter.event);
1209 				kfree(waiter);
1210 			}
1211 		}
1212 
1213 	}
1214 	else {
1215 		vchiq_log_error(vchiq_arm_log_level,
1216 			"Unknown minor device");
1217 		ret = -ENXIO;
1218 	}
1219 
1220 out:
1221 	return ret;
1222 }
1223 
1224 /****************************************************************************
1225 *
1226 *   vchiq_dump
1227 *
1228 ***************************************************************************/
1229 
1230 void
1231 vchiq_dump(void *dump_context, const char *str, int len)
1232 {
1233 	DUMP_CONTEXT_T *context = (DUMP_CONTEXT_T *)dump_context;
1234 
1235 	if (context->actual < context->space) {
1236 		int copy_bytes;
1237 		if (context->offset > 0) {
1238 			int skip_bytes = min(len, (int)context->offset);
1239 			str += skip_bytes;
1240 			len -= skip_bytes;
1241 			context->offset -= skip_bytes;
1242 			if (context->offset > 0)
1243 				return;
1244 		}
1245 		copy_bytes = min(len, (int)(context->space - context->actual));
1246 		if (copy_bytes == 0)
1247 			return;
1248 		if (copy_to_user(context->buf + context->actual, str,
1249 			copy_bytes))
1250 			context->actual = -EFAULT;
1251 		context->actual += copy_bytes;
1252 		len -= copy_bytes;
1253 
1254 		/* If tne terminating NUL is included in the length, then it
1255 		** marks the end of a line and should be replaced with a
1256 		** carriage return. */
1257 		if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
1258 			char cr = '\n';
1259 			if (copy_to_user(context->buf + context->actual - 1,
1260 				&cr, 1))
1261 				context->actual = -EFAULT;
1262 		}
1263 	}
1264 }
1265 
1266 /****************************************************************************
1267 *
1268 *   vchiq_dump_platform_instance_state
1269 *
1270 ***************************************************************************/
1271 
1272 void
1273 vchiq_dump_platform_instances(void *dump_context)
1274 {
1275 	VCHIQ_STATE_T *state = vchiq_get_state();
1276 	char buf[80];
1277 	int len;
1278 	int i;
1279 
1280 	/* There is no list of instances, so instead scan all services,
1281 		marking those that have been dumped. */
1282 
1283 	for (i = 0; i < state->unused_service; i++) {
1284 		VCHIQ_SERVICE_T *service = state->services[i];
1285 		VCHIQ_INSTANCE_T instance;
1286 
1287 		if (service && (service->base.callback == service_callback)) {
1288 			instance = service->instance;
1289 			if (instance)
1290 				instance->mark = 0;
1291 		}
1292 	}
1293 
1294 	for (i = 0; i < state->unused_service; i++) {
1295 		VCHIQ_SERVICE_T *service = state->services[i];
1296 		VCHIQ_INSTANCE_T instance;
1297 
1298 		if (service && (service->base.callback == service_callback)) {
1299 			instance = service->instance;
1300 			if (instance && !instance->mark) {
1301 				len = snprintf(buf, sizeof(buf),
1302 					"Instance %x: lwp %p,%s completions "
1303 						"%d/%d",
1304 					(unsigned int)instance, instance->l,
1305 					instance->connected ? " connected, " :
1306 						"",
1307 					instance->completion_insert -
1308 						instance->completion_remove,
1309 					MAX_COMPLETIONS);
1310 
1311 				vchiq_dump(dump_context, buf, len + 1);
1312 
1313 				instance->mark = 1;
1314 			}
1315 		}
1316 	}
1317 }
1318 
1319 /****************************************************************************
1320 *
1321 *   vchiq_dump_platform_service_state
1322 *
1323 ***************************************************************************/
1324 
1325 void
1326 vchiq_dump_platform_service_state(void *dump_context, VCHIQ_SERVICE_T *service)
1327 {
1328 	USER_SERVICE_T *user_service = (USER_SERVICE_T *)service->base.userdata;
1329 	char buf[80];
1330 	int len;
1331 
1332 	len = snprintf(buf, sizeof(buf), "  instance %x",
1333 		(unsigned int)service->instance);
1334 
1335 	if ((service->base.callback == service_callback) &&
1336 		user_service->is_vchi) {
1337 		len += snprintf(buf + len, sizeof(buf) - len,
1338 			", %d/%d messages",
1339 			user_service->msg_insert - user_service->msg_remove,
1340 			MSG_QUEUE_SIZE);
1341 
1342 		if (user_service->dequeue_pending)
1343 			len += snprintf(buf + len, sizeof(buf) - len,
1344 				" (dequeue pending)");
1345 	}
1346 
1347 	vchiq_dump(dump_context, buf, len + 1);
1348 }
1349 
1350 #ifdef notyet
1351 /****************************************************************************
1352 *
1353 *   dump_user_mem
1354 *
1355 ***************************************************************************/
1356 
1357 static void
1358 dump_phys_mem(void *virt_addr, uint32_t num_bytes)
1359 {
1360 	int            rc;
1361 	uint8_t       *end_virt_addr = virt_addr + num_bytes;
1362 	int            num_pages;
1363 	int            offset;
1364 	int            end_offset;
1365 	int            page_idx;
1366 	int            prev_idx;
1367 	struct page   *page;
1368 	struct page  **pages;
1369 	uint8_t       *kmapped_virt_ptr;
1370 
1371 	/* Align virtAddr and endVirtAddr to 16 byte boundaries. */
1372 
1373 	virt_addr = (void *)((unsigned long)virt_addr & ~0x0fuL);
1374 	end_virt_addr = (void *)(((unsigned long)end_virt_addr + 15uL) &
1375 		~0x0fuL);
1376 
1377 	offset = (int)(long)virt_addr & (PAGE_SIZE - 1);
1378 	end_offset = (int)(long)end_virt_addr & (PAGE_SIZE - 1);
1379 
1380 	num_pages = (offset + num_bytes + PAGE_SIZE - 1) / PAGE_SIZE;
1381 
1382 	pages = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1383 	if (pages == NULL) {
1384 		vchiq_log_error(vchiq_arm_log_level,
1385 			"Unable to allocation memory for %d pages\n",
1386 			num_pages);
1387 		return;
1388 	}
1389 
1390 	down_read(&current->mm->mmap_sem);
1391 	rc = get_user_pages(current,      /* task */
1392 		current->mm,              /* mm */
1393 		(unsigned long)virt_addr, /* start */
1394 		num_pages,                /* len */
1395 		0,                        /* write */
1396 		0,                        /* force */
1397 		pages,                    /* pages (array of page pointers) */
1398 		NULL);                    /* vmas */
1399 	up_read(&current->mm->mmap_sem);
1400 
1401 	prev_idx = -1;
1402 	page = NULL;
1403 
1404 	while (offset < end_offset) {
1405 
1406 		int page_offset = offset % PAGE_SIZE;
1407 		page_idx = offset / PAGE_SIZE;
1408 
1409 		if (page_idx != prev_idx) {
1410 
1411 			if (page != NULL)
1412 				kunmap(page);
1413 			page = pages[page_idx];
1414 			kmapped_virt_ptr = kmap(page);
1415 
1416 			prev_idx = page_idx;
1417 		}
1418 
1419 		if (vchiq_arm_log_level >= VCHIQ_LOG_TRACE)
1420 			vchiq_log_dump_mem("ph",
1421 				(uint32_t)(unsigned long)&kmapped_virt_ptr[
1422 					page_offset],
1423 				&kmapped_virt_ptr[page_offset], 16);
1424 
1425 		offset += 16;
1426 	}
1427 	if (page != NULL)
1428 		kunmap(page);
1429 
1430 	for (page_idx = 0; page_idx < num_pages; page_idx++)
1431 		page_cache_release(pages[page_idx]);
1432 
1433 	kfree(pages);
1434 }
1435 
1436 /****************************************************************************
1437 *
1438 *   vchiq_read
1439 *
1440 ***************************************************************************/
1441 
1442 static ssize_t
1443 vchiq_read(struct file *file, char __user *buf,
1444 	size_t count, loff_t *ppos)
1445 {
1446 	DUMP_CONTEXT_T context;
1447 	context.buf = buf;
1448 	context.actual = 0;
1449 	context.space = count;
1450 	context.offset = *ppos;
1451 
1452 	vchiq_dump_state(&context, &g_state);
1453 
1454 	*ppos += context.actual;
1455 
1456 	return context.actual;
1457 }
1458 #endif
1459 
1460 VCHIQ_STATE_T *
1461 vchiq_get_state(void)
1462 {
1463 
1464 	if (g_state.remote == NULL)
1465 		printk(KERN_ERR "%s: g_state.remote == NULL\n", __func__);
1466 	else if (g_state.remote->initialised != 1)
1467 		printk(KERN_NOTICE "%s: g_state.remote->initialised != 1 (%d)\n",
1468 			__func__, g_state.remote->initialised);
1469 
1470 	return ((g_state.remote != NULL) &&
1471 		(g_state.remote->initialised == 1)) ? &g_state : NULL;
1472 }
1473 
1474 /*
1475  * Autosuspend related functionality
1476  */
1477 
1478 int
1479 vchiq_videocore_wanted(VCHIQ_STATE_T *state)
1480 {
1481 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1482 	if (!arm_state)
1483 		/* autosuspend not supported - always return wanted */
1484 		return 1;
1485 	else if (arm_state->blocked_count)
1486 		return 1;
1487 	else if (!arm_state->videocore_use_count)
1488 		/* usage count zero - check for override unless we're forcing */
1489 		if (arm_state->resume_blocked)
1490 			return 0;
1491 		else
1492 			return vchiq_platform_videocore_wanted(state);
1493 	else
1494 		/* non-zero usage count - videocore still required */
1495 		return 1;
1496 }
1497 
1498 static VCHIQ_STATUS_T
1499 vchiq_keepalive_vchiq_callback(VCHIQ_REASON_T reason,
1500 	VCHIQ_HEADER_T *header,
1501 	VCHIQ_SERVICE_HANDLE_T service_user,
1502 	void *bulk_user)
1503 {
1504 	vchiq_log_error(vchiq_susp_log_level,
1505 		"%s callback reason %d", __func__, reason);
1506 	return 0;
1507 }
1508 
1509 static int
1510 vchiq_keepalive_thread_func(void *v)
1511 {
1512 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *) v;
1513 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1514 
1515 	VCHIQ_STATUS_T status;
1516 	VCHIQ_INSTANCE_T instance;
1517 	VCHIQ_SERVICE_HANDLE_T ka_handle;
1518 
1519 	VCHIQ_SERVICE_PARAMS_T params = {
1520 		.fourcc      = VCHIQ_MAKE_FOURCC('K', 'E', 'E', 'P'),
1521 		.callback    = vchiq_keepalive_vchiq_callback,
1522 		.version     = KEEPALIVE_VER,
1523 		.version_min = KEEPALIVE_VER_MIN
1524 	};
1525 
1526 	status = vchiq_initialise(&instance);
1527 	if (status != VCHIQ_SUCCESS) {
1528 		vchiq_log_error(vchiq_susp_log_level,
1529 			"%s vchiq_initialise failed %d", __func__, status);
1530 		goto exit;
1531 	}
1532 
1533 	status = vchiq_connect(instance);
1534 	if (status != VCHIQ_SUCCESS) {
1535 		vchiq_log_error(vchiq_susp_log_level,
1536 			"%s vchiq_connect failed %d", __func__, status);
1537 		goto shutdown;
1538 	}
1539 
1540 	status = vchiq_add_service(instance, &params, &ka_handle);
1541 	if (status != VCHIQ_SUCCESS) {
1542 		vchiq_log_error(vchiq_susp_log_level,
1543 			"%s vchiq_open_service failed %d", __func__, status);
1544 		goto shutdown;
1545 	}
1546 
1547 	while (1) {
1548 		long rc = 0, uc = 0;
1549 		if (wait_for_completion_interruptible(&arm_state->ka_evt)
1550 				!= 0) {
1551 			vchiq_log_error(vchiq_susp_log_level,
1552 				"%s interrupted", __func__);
1553 			flush_signals(current);
1554 			continue;
1555 		}
1556 
1557 		/* read and clear counters.  Do release_count then use_count to
1558 		 * prevent getting more releases than uses */
1559 		rc = atomic_xchg(&arm_state->ka_release_count, 0);
1560 		uc = atomic_xchg(&arm_state->ka_use_count, 0);
1561 
1562 		/* Call use/release service the requisite number of times.
1563 		 * Process use before release so use counts don't go negative */
1564 		while (uc--) {
1565 			atomic_inc(&arm_state->ka_use_ack_count);
1566 			status = vchiq_use_service(ka_handle);
1567 			if (status != VCHIQ_SUCCESS) {
1568 				vchiq_log_error(vchiq_susp_log_level,
1569 					"%s vchiq_use_service error %d",
1570 					__func__, status);
1571 			}
1572 		}
1573 		while (rc--) {
1574 			status = vchiq_release_service(ka_handle);
1575 			if (status != VCHIQ_SUCCESS) {
1576 				vchiq_log_error(vchiq_susp_log_level,
1577 					"%s vchiq_release_service error %d",
1578 					__func__, status);
1579 			}
1580 		}
1581 	}
1582 
1583 shutdown:
1584 	vchiq_shutdown(instance);
1585 exit:
1586 	return 0;
1587 }
1588 
1589 VCHIQ_STATUS_T
1590 vchiq_arm_init_state(VCHIQ_STATE_T *state, VCHIQ_ARM_STATE_T *arm_state)
1591 {
1592 	VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
1593 
1594 	if (arm_state) {
1595 		rwlock_init(&arm_state->susp_res_lock);
1596 
1597 		init_completion(&arm_state->ka_evt);
1598 		atomic_set(&arm_state->ka_use_count, 0);
1599 		atomic_set(&arm_state->ka_use_ack_count, 0);
1600 		atomic_set(&arm_state->ka_release_count, 0);
1601 
1602 		init_completion(&arm_state->vc_suspend_complete);
1603 
1604 		init_completion(&arm_state->vc_resume_complete);
1605 		/* Initialise to 'done' state.  We only want to block on resume
1606 		 * completion while videocore is suspended. */
1607 		set_resume_state(arm_state, VC_RESUME_RESUMED);
1608 
1609 		init_completion(&arm_state->resume_blocker);
1610 		/* Initialise to 'done' state.  We only want to block on this
1611 		 * completion while resume is blocked */
1612 		complete_all(&arm_state->resume_blocker);
1613 
1614 		init_completion(&arm_state->blocked_blocker);
1615 		/* Initialise to 'done' state.  We only want to block on this
1616 		 * completion while things are waiting on the resume blocker */
1617 		complete_all(&arm_state->blocked_blocker);
1618 
1619 		arm_state->suspend_timer_timeout = SUSPEND_TIMER_TIMEOUT_MS;
1620 		arm_state->suspend_timer_running = 0;
1621 		init_timer(&arm_state->suspend_timer);
1622 		arm_state->suspend_timer.data = (unsigned long)(state);
1623 		arm_state->suspend_timer.function = suspend_timer_callback;
1624 
1625 		arm_state->first_connect = 0;
1626 
1627 	}
1628 	return status;
1629 }
1630 
1631 /*
1632 ** Functions to modify the state variables;
1633 **	set_suspend_state
1634 **	set_resume_state
1635 **
1636 ** There are more state variables than we might like, so ensure they remain in
1637 ** step.  Suspend and resume state are maintained separately, since most of
1638 ** these state machines can operate independently.  However, there are a few
1639 ** states where state transitions in one state machine cause a reset to the
1640 ** other state machine.  In addition, there are some completion events which
1641 ** need to occur on state machine reset and end-state(s), so these are also
1642 ** dealt with in these functions.
1643 **
1644 ** In all states we set the state variable according to the input, but in some
1645 ** cases we perform additional steps outlined below;
1646 **
1647 ** VC_SUSPEND_IDLE - Initialise the suspend completion at the same time.
1648 **			The suspend completion is completed after any suspend
1649 **			attempt.  When we reset the state machine we also reset
1650 **			the completion.  This reset occurs when videocore is
1651 **			resumed, and also if we initiate suspend after a suspend
1652 **			failure.
1653 **
1654 ** VC_SUSPEND_IN_PROGRESS - This state is considered the point of no return for
1655 **			suspend - ie from this point on we must try to suspend
1656 **			before resuming can occur.  We therefore also reset the
1657 **			resume state machine to VC_RESUME_IDLE in this state.
1658 **
1659 ** VC_SUSPEND_SUSPENDED - Suspend has completed successfully. Also call
1660 **			complete_all on the suspend completion to notify
1661 **			anything waiting for suspend to happen.
1662 **
1663 ** VC_SUSPEND_REJECTED - Videocore rejected suspend. Videocore will also
1664 **			initiate resume, so no need to alter resume state.
1665 **			We call complete_all on the suspend completion to notify
1666 **			of suspend rejection.
1667 **
1668 ** VC_SUSPEND_FAILED - We failed to initiate videocore suspend.  We notify the
1669 **			suspend completion and reset the resume state machine.
1670 **
1671 ** VC_RESUME_IDLE - Initialise the resume completion at the same time.  The
1672 **			resume completion is in it's 'done' state whenever
1673 **			videcore is running.  Therfore, the VC_RESUME_IDLE state
1674 **			implies that videocore is suspended.
1675 **			Hence, any thread which needs to wait until videocore is
1676 **			running can wait on this completion - it will only block
1677 **			if videocore is suspended.
1678 **
1679 ** VC_RESUME_RESUMED - Resume has completed successfully.  Videocore is running.
1680 **			Call complete_all on the resume completion to unblock
1681 **			any threads waiting for resume.	 Also reset the suspend
1682 **			state machine to it's idle state.
1683 **
1684 ** VC_RESUME_FAILED - Currently unused - no mechanism to fail resume exists.
1685 */
1686 
1687 inline void
1688 set_suspend_state(VCHIQ_ARM_STATE_T *arm_state,
1689 	enum vc_suspend_status new_state)
1690 {
1691 	/* set the state in all cases */
1692 	arm_state->vc_suspend_state = new_state;
1693 
1694 	/* state specific additional actions */
1695 	switch (new_state) {
1696 	case VC_SUSPEND_FORCE_CANCELED:
1697 		complete_all(&arm_state->vc_suspend_complete);
1698 		break;
1699 	case VC_SUSPEND_REJECTED:
1700 		complete_all(&arm_state->vc_suspend_complete);
1701 		break;
1702 	case VC_SUSPEND_FAILED:
1703 		complete_all(&arm_state->vc_suspend_complete);
1704 		arm_state->vc_resume_state = VC_RESUME_RESUMED;
1705 		complete_all(&arm_state->vc_resume_complete);
1706 		break;
1707 	case VC_SUSPEND_IDLE:
1708 		INIT_COMPLETION(arm_state->vc_suspend_complete);
1709 		break;
1710 	case VC_SUSPEND_REQUESTED:
1711 		break;
1712 	case VC_SUSPEND_IN_PROGRESS:
1713 		set_resume_state(arm_state, VC_RESUME_IDLE);
1714 		break;
1715 	case VC_SUSPEND_SUSPENDED:
1716 		complete_all(&arm_state->vc_suspend_complete);
1717 		break;
1718 	default:
1719 		BUG();
1720 		break;
1721 	}
1722 }
1723 
1724 inline void
1725 set_resume_state(VCHIQ_ARM_STATE_T *arm_state,
1726 	enum vc_resume_status new_state)
1727 {
1728 	/* set the state in all cases */
1729 	arm_state->vc_resume_state = new_state;
1730 
1731 	/* state specific additional actions */
1732 	switch (new_state) {
1733 	case VC_RESUME_FAILED:
1734 		break;
1735 	case VC_RESUME_IDLE:
1736 		INIT_COMPLETION(arm_state->vc_resume_complete);
1737 		break;
1738 	case VC_RESUME_REQUESTED:
1739 		break;
1740 	case VC_RESUME_IN_PROGRESS:
1741 		break;
1742 	case VC_RESUME_RESUMED:
1743 		complete_all(&arm_state->vc_resume_complete);
1744 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1745 		break;
1746 	default:
1747 		BUG();
1748 		break;
1749 	}
1750 }
1751 
1752 
1753 /* should be called with the write lock held */
1754 inline void
1755 start_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1756 {
1757 	del_timer(&arm_state->suspend_timer);
1758 	arm_state->suspend_timer.expires = jiffies +
1759 		msecs_to_jiffies(arm_state->
1760 			suspend_timer_timeout);
1761 	add_timer(&arm_state->suspend_timer);
1762 	arm_state->suspend_timer_running = 1;
1763 }
1764 
1765 /* should be called with the write lock held */
1766 static inline void
1767 stop_suspend_timer(VCHIQ_ARM_STATE_T *arm_state)
1768 {
1769 	if (arm_state->suspend_timer_running) {
1770 		del_timer(&arm_state->suspend_timer);
1771 		arm_state->suspend_timer_running = 0;
1772 	}
1773 }
1774 
1775 static inline int
1776 need_resume(VCHIQ_STATE_T *state)
1777 {
1778 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1779 	return (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) &&
1780 			(arm_state->vc_resume_state < VC_RESUME_REQUESTED) &&
1781 			vchiq_videocore_wanted(state);
1782 }
1783 
1784 static int
1785 block_resume(VCHIQ_ARM_STATE_T *arm_state)
1786 {
1787 	int status = VCHIQ_SUCCESS;
1788 	const unsigned long timeout_val =
1789 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS);
1790 	int resume_count = 0;
1791 
1792 	/* Allow any threads which were blocked by the last force suspend to
1793 	 * complete if they haven't already.  Only give this one shot; if
1794 	 * blocked_count is incremented after blocked_blocker is completed
1795 	 * (which only happens when blocked_count hits 0) then those threads
1796 	 * will have to wait until next time around */
1797 	if (arm_state->blocked_count) {
1798 		INIT_COMPLETION(arm_state->blocked_blocker);
1799 		write_unlock_bh(&arm_state->susp_res_lock);
1800 		vchiq_log_info(vchiq_susp_log_level, "%s wait for previously "
1801 			"blocked clients", __func__);
1802 		if (wait_for_completion_interruptible_timeout(
1803 				&arm_state->blocked_blocker, timeout_val)
1804 					<= 0) {
1805 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1806 				"previously blocked clients failed" , __func__);
1807 			status = VCHIQ_ERROR;
1808 			write_lock_bh(&arm_state->susp_res_lock);
1809 			goto out;
1810 		}
1811 		vchiq_log_info(vchiq_susp_log_level, "%s previously blocked "
1812 			"clients resumed", __func__);
1813 		write_lock_bh(&arm_state->susp_res_lock);
1814 	}
1815 
1816 	/* We need to wait for resume to complete if it's in process */
1817 	while (arm_state->vc_resume_state != VC_RESUME_RESUMED &&
1818 			arm_state->vc_resume_state > VC_RESUME_IDLE) {
1819 		if (resume_count > 1) {
1820 			status = VCHIQ_ERROR;
1821 			vchiq_log_error(vchiq_susp_log_level, "%s waited too "
1822 				"many times for resume" , __func__);
1823 			goto out;
1824 		}
1825 		write_unlock_bh(&arm_state->susp_res_lock);
1826 		vchiq_log_info(vchiq_susp_log_level, "%s wait for resume",
1827 			__func__);
1828 		if (wait_for_completion_interruptible_timeout(
1829 				&arm_state->vc_resume_complete, timeout_val)
1830 					<= 0) {
1831 			vchiq_log_error(vchiq_susp_log_level, "%s wait for "
1832 				"resume failed (%s)", __func__,
1833 				resume_state_names[arm_state->vc_resume_state +
1834 							VC_RESUME_NUM_OFFSET]);
1835 			status = VCHIQ_ERROR;
1836 			write_lock_bh(&arm_state->susp_res_lock);
1837 			goto out;
1838 		}
1839 		vchiq_log_info(vchiq_susp_log_level, "%s resumed", __func__);
1840 		write_lock_bh(&arm_state->susp_res_lock);
1841 		resume_count++;
1842 	}
1843 	INIT_COMPLETION(arm_state->resume_blocker);
1844 	arm_state->resume_blocked = 1;
1845 
1846 out:
1847 	return status;
1848 }
1849 
1850 static inline void
1851 unblock_resume(VCHIQ_ARM_STATE_T *arm_state)
1852 {
1853 	complete_all(&arm_state->resume_blocker);
1854 	arm_state->resume_blocked = 0;
1855 }
1856 
1857 /* Initiate suspend via slot handler. Should be called with the write lock
1858  * held */
1859 VCHIQ_STATUS_T
1860 vchiq_arm_vcsuspend(VCHIQ_STATE_T *state)
1861 {
1862 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1863 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1864 
1865 	if (!arm_state)
1866 		goto out;
1867 
1868 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1869 	status = VCHIQ_SUCCESS;
1870 
1871 
1872 	switch (arm_state->vc_suspend_state) {
1873 	case VC_SUSPEND_REQUESTED:
1874 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already "
1875 			"requested", __func__);
1876 		break;
1877 	case VC_SUSPEND_IN_PROGRESS:
1878 		vchiq_log_info(vchiq_susp_log_level, "%s: suspend already in "
1879 			"progress", __func__);
1880 		break;
1881 
1882 	default:
1883 		/* We don't expect to be in other states, so log but continue
1884 		 * anyway */
1885 		vchiq_log_error(vchiq_susp_log_level,
1886 			"%s unexpected suspend state %s", __func__,
1887 			suspend_state_names[arm_state->vc_suspend_state +
1888 						VC_SUSPEND_NUM_OFFSET]);
1889 		/* fall through */
1890 	case VC_SUSPEND_REJECTED:
1891 	case VC_SUSPEND_FAILED:
1892 		/* Ensure any idle state actions have been run */
1893 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
1894 		/* fall through */
1895 	case VC_SUSPEND_IDLE:
1896 		vchiq_log_info(vchiq_susp_log_level,
1897 			"%s: suspending", __func__);
1898 		set_suspend_state(arm_state, VC_SUSPEND_REQUESTED);
1899 		/* kick the slot handler thread to initiate suspend */
1900 		request_poll(state, NULL, 0);
1901 		break;
1902 	}
1903 
1904 out:
1905 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
1906 	return status;
1907 }
1908 
1909 void
1910 vchiq_platform_check_suspend(VCHIQ_STATE_T *state)
1911 {
1912 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1913 	int susp = 0;
1914 
1915 	if (!arm_state)
1916 		goto out;
1917 
1918 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1919 
1920 	write_lock_bh(&arm_state->susp_res_lock);
1921 	if (arm_state->vc_suspend_state == VC_SUSPEND_REQUESTED &&
1922 			arm_state->vc_resume_state == VC_RESUME_RESUMED) {
1923 		set_suspend_state(arm_state, VC_SUSPEND_IN_PROGRESS);
1924 		susp = 1;
1925 	}
1926 	write_unlock_bh(&arm_state->susp_res_lock);
1927 
1928 	if (susp)
1929 		vchiq_platform_suspend(state);
1930 
1931 out:
1932 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
1933 	return;
1934 }
1935 
1936 
1937 static void
1938 output_timeout_error(VCHIQ_STATE_T *state)
1939 {
1940 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1941 	char service_err[50] = "";
1942 	int vc_use_count = arm_state->videocore_use_count;
1943 	int active_services = state->unused_service;
1944 	int i;
1945 
1946 	if (!arm_state->videocore_use_count) {
1947 		snprintf(service_err, 50, " Videocore usecount is 0");
1948 		goto output_msg;
1949 	}
1950 	for (i = 0; i < active_services; i++) {
1951 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
1952 		if (service_ptr && service_ptr->service_use_count &&
1953 			(service_ptr->srvstate != VCHIQ_SRVSTATE_FREE)) {
1954 			snprintf(service_err, 50, " %c%c%c%c(%8x) service has "
1955 				"use count %d%s", VCHIQ_FOURCC_AS_4CHARS(
1956 					service_ptr->base.fourcc),
1957 				 service_ptr->client_id,
1958 				 service_ptr->service_use_count,
1959 				 service_ptr->service_use_count ==
1960 					 vc_use_count ? "" : " (+ more)");
1961 			break;
1962 		}
1963 	}
1964 
1965 output_msg:
1966 	vchiq_log_error(vchiq_susp_log_level,
1967 		"timed out waiting for vc suspend (%d).%s",
1968 		 arm_state->autosuspend_override, service_err);
1969 
1970 }
1971 
1972 /* Try to get videocore into suspended state, regardless of autosuspend state.
1973 ** We don't actually force suspend, since videocore may get into a bad state
1974 ** if we force suspend at a bad time.  Instead, we wait for autosuspend to
1975 ** determine a good point to suspend.  If this doesn't happen within 100ms we
1976 ** report failure.
1977 **
1978 ** Returns VCHIQ_SUCCESS if videocore suspended successfully, VCHIQ_RETRY if
1979 ** videocore failed to suspend in time or VCHIQ_ERROR if interrupted.
1980 */
1981 VCHIQ_STATUS_T
1982 vchiq_arm_force_suspend(VCHIQ_STATE_T *state)
1983 {
1984 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
1985 	VCHIQ_STATUS_T status = VCHIQ_ERROR;
1986 	long rc = 0;
1987 	int repeat = -1;
1988 
1989 	if (!arm_state)
1990 		goto out;
1991 
1992 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
1993 
1994 	write_lock_bh(&arm_state->susp_res_lock);
1995 
1996 	status = block_resume(arm_state);
1997 	if (status != VCHIQ_SUCCESS)
1998 		goto unlock;
1999 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2000 		/* Already suspended - just block resume and exit */
2001 		vchiq_log_info(vchiq_susp_log_level, "%s already suspended",
2002 			__func__);
2003 		status = VCHIQ_SUCCESS;
2004 		goto unlock;
2005 	} else if (arm_state->vc_suspend_state <= VC_SUSPEND_IDLE) {
2006 		/* initiate suspend immediately in the case that we're waiting
2007 		 * for the timeout */
2008 		stop_suspend_timer(arm_state);
2009 		if (!vchiq_videocore_wanted(state)) {
2010 			vchiq_log_info(vchiq_susp_log_level, "%s videocore "
2011 				"idle, initiating suspend", __func__);
2012 			status = vchiq_arm_vcsuspend(state);
2013 		} else if (arm_state->autosuspend_override <
2014 						FORCE_SUSPEND_FAIL_MAX) {
2015 			vchiq_log_info(vchiq_susp_log_level, "%s letting "
2016 				"videocore go idle", __func__);
2017 			status = VCHIQ_SUCCESS;
2018 		} else {
2019 			vchiq_log_warning(vchiq_susp_log_level, "%s failed too "
2020 				"many times - attempting suspend", __func__);
2021 			status = vchiq_arm_vcsuspend(state);
2022 		}
2023 	} else {
2024 		vchiq_log_info(vchiq_susp_log_level, "%s videocore suspend "
2025 			"in progress - wait for completion", __func__);
2026 		status = VCHIQ_SUCCESS;
2027 	}
2028 
2029 	/* Wait for suspend to happen due to system idle (not forced..) */
2030 	if (status != VCHIQ_SUCCESS)
2031 		goto unblock_resume;
2032 
2033 	do {
2034 		write_unlock_bh(&arm_state->susp_res_lock);
2035 
2036 		rc = wait_for_completion_interruptible_timeout(
2037 				&arm_state->vc_suspend_complete,
2038 				msecs_to_jiffies(FORCE_SUSPEND_TIMEOUT_MS));
2039 
2040 		write_lock_bh(&arm_state->susp_res_lock);
2041 		if (rc < 0) {
2042 			vchiq_log_warning(vchiq_susp_log_level, "%s "
2043 				"interrupted waiting for suspend", __func__);
2044 			status = VCHIQ_ERROR;
2045 			goto unblock_resume;
2046 		} else if (rc == 0) {
2047 			if (arm_state->vc_suspend_state > VC_SUSPEND_IDLE) {
2048 				/* Repeat timeout once if in progress */
2049 				if (repeat < 0) {
2050 					repeat = 1;
2051 					continue;
2052 				}
2053 			}
2054 			arm_state->autosuspend_override++;
2055 			output_timeout_error(state);
2056 
2057 			status = VCHIQ_RETRY;
2058 			goto unblock_resume;
2059 		}
2060 	} while (0 < (repeat--));
2061 
2062 	/* Check and report state in case we need to abort ARM suspend */
2063 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED) {
2064 		status = VCHIQ_RETRY;
2065 		vchiq_log_error(vchiq_susp_log_level,
2066 			"%s videocore suspend failed (state %s)", __func__,
2067 			suspend_state_names[arm_state->vc_suspend_state +
2068 						VC_SUSPEND_NUM_OFFSET]);
2069 		/* Reset the state only if it's still in an error state.
2070 		 * Something could have already initiated another suspend. */
2071 		if (arm_state->vc_suspend_state < VC_SUSPEND_IDLE)
2072 			set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2073 
2074 		goto unblock_resume;
2075 	}
2076 
2077 	/* successfully suspended - unlock and exit */
2078 	goto unlock;
2079 
2080 unblock_resume:
2081 	/* all error states need to unblock resume before exit */
2082 	unblock_resume(arm_state);
2083 
2084 unlock:
2085 	write_unlock_bh(&arm_state->susp_res_lock);
2086 
2087 out:
2088 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, status);
2089 	return status;
2090 }
2091 
2092 void
2093 vchiq_check_suspend(VCHIQ_STATE_T *state)
2094 {
2095 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2096 
2097 	if (!arm_state)
2098 		goto out;
2099 
2100 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2101 
2102 	write_lock_bh(&arm_state->susp_res_lock);
2103 	if (arm_state->vc_suspend_state != VC_SUSPEND_SUSPENDED &&
2104 			arm_state->first_connect &&
2105 			!vchiq_videocore_wanted(state)) {
2106 		vchiq_arm_vcsuspend(state);
2107 	}
2108 	write_unlock_bh(&arm_state->susp_res_lock);
2109 
2110 out:
2111 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2112 	return;
2113 }
2114 
2115 
2116 int
2117 vchiq_arm_allow_resume(VCHIQ_STATE_T *state)
2118 {
2119 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2120 	int resume = 0;
2121 	int ret = -1;
2122 
2123 	if (!arm_state)
2124 		goto out;
2125 
2126 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2127 
2128 	write_lock_bh(&arm_state->susp_res_lock);
2129 	unblock_resume(arm_state);
2130 	resume = vchiq_check_resume(state);
2131 	write_unlock_bh(&arm_state->susp_res_lock);
2132 
2133 	if (resume) {
2134 		if (wait_for_completion_interruptible(
2135 			&arm_state->vc_resume_complete) < 0) {
2136 			vchiq_log_error(vchiq_susp_log_level,
2137 				"%s interrupted", __func__);
2138 			/* failed, cannot accurately derive suspend
2139 			 * state, so exit early. */
2140 			goto out;
2141 		}
2142 	}
2143 
2144 	read_lock_bh(&arm_state->susp_res_lock);
2145 	if (arm_state->vc_suspend_state == VC_SUSPEND_SUSPENDED) {
2146 		vchiq_log_info(vchiq_susp_log_level,
2147 				"%s: Videocore remains suspended", __func__);
2148 	} else {
2149 		vchiq_log_info(vchiq_susp_log_level,
2150 				"%s: Videocore resumed", __func__);
2151 		ret = 0;
2152 	}
2153 	read_unlock_bh(&arm_state->susp_res_lock);
2154 out:
2155 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2156 	return ret;
2157 }
2158 
2159 /* This function should be called with the write lock held */
2160 int
2161 vchiq_check_resume(VCHIQ_STATE_T *state)
2162 {
2163 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2164 	int resume = 0;
2165 
2166 	if (!arm_state)
2167 		goto out;
2168 
2169 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2170 
2171 	if (need_resume(state)) {
2172 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2173 		request_poll(state, NULL, 0);
2174 		resume = 1;
2175 	}
2176 
2177 out:
2178 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2179 	return resume;
2180 }
2181 
2182 #ifdef notyet
2183 void
2184 vchiq_platform_check_resume(VCHIQ_STATE_T *state)
2185 {
2186 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2187 	int res = 0;
2188 
2189 	if (!arm_state)
2190 		goto out;
2191 
2192 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2193 
2194 	write_lock_bh(&arm_state->susp_res_lock);
2195 	if (arm_state->wake_address == 0) {
2196 		vchiq_log_info(vchiq_susp_log_level,
2197 					"%s: already awake", __func__);
2198 		goto unlock;
2199 	}
2200 	if (arm_state->vc_resume_state == VC_RESUME_IN_PROGRESS) {
2201 		vchiq_log_info(vchiq_susp_log_level,
2202 					"%s: already resuming", __func__);
2203 		goto unlock;
2204 	}
2205 
2206 	if (arm_state->vc_resume_state == VC_RESUME_REQUESTED) {
2207 		set_resume_state(arm_state, VC_RESUME_IN_PROGRESS);
2208 		res = 1;
2209 	} else
2210 		vchiq_log_trace(vchiq_susp_log_level,
2211 				"%s: not resuming (resume state %s)", __func__,
2212 				resume_state_names[arm_state->vc_resume_state +
2213 							VC_RESUME_NUM_OFFSET]);
2214 
2215 unlock:
2216 	write_unlock_bh(&arm_state->susp_res_lock);
2217 
2218 	if (res)
2219 		vchiq_platform_resume(state);
2220 
2221 out:
2222 	vchiq_log_trace(vchiq_susp_log_level, "%s exit", __func__);
2223 	return;
2224 
2225 }
2226 #endif
2227 
2228 
2229 
2230 VCHIQ_STATUS_T
2231 vchiq_use_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service,
2232 		enum USE_TYPE_E use_type)
2233 {
2234 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2235 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2236 	char entity[16];
2237 	int *entity_uc;
2238 	int local_uc, local_entity_uc;
2239 
2240 	if (!arm_state)
2241 		goto out;
2242 
2243 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2244 
2245 	if (use_type == USE_TYPE_VCHIQ) {
2246 		snprintf(entity, sizeof(entity), "VCHIQ:   ");
2247 		entity_uc = &arm_state->peer_use_count;
2248 	} else if (service) {
2249 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2250 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2251 			service->client_id);
2252 		entity_uc = &service->service_use_count;
2253 	} else {
2254 		vchiq_log_error(vchiq_susp_log_level, "%s null service "
2255 				"ptr", __func__);
2256 		ret = VCHIQ_ERROR;
2257 		goto out;
2258 	}
2259 
2260 	write_lock_bh(&arm_state->susp_res_lock);
2261 	while (arm_state->resume_blocked) {
2262 		/* If we call 'use' while force suspend is waiting for suspend,
2263 		 * then we're about to block the thread which the force is
2264 		 * waiting to complete, so we're bound to just time out. In this
2265 		 * case, set the suspend state such that the wait will be
2266 		 * canceled, so we can complete as quickly as possible. */
2267 		if (arm_state->resume_blocked && arm_state->vc_suspend_state ==
2268 				VC_SUSPEND_IDLE) {
2269 			set_suspend_state(arm_state, VC_SUSPEND_FORCE_CANCELED);
2270 			break;
2271 		}
2272 		/* If suspend is already in progress then we need to block */
2273 		if (!try_wait_for_completion(&arm_state->resume_blocker)) {
2274 			/* Indicate that there are threads waiting on the resume
2275 			 * blocker.  These need to be allowed to complete before
2276 			 * a _second_ call to force suspend can complete,
2277 			 * otherwise low priority threads might never actually
2278 			 * continue */
2279 			arm_state->blocked_count++;
2280 			write_unlock_bh(&arm_state->susp_res_lock);
2281 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2282 				"blocked - waiting...", __func__, entity);
2283 			if (wait_for_completion_killable(
2284 					&arm_state->resume_blocker) != 0) {
2285 				vchiq_log_error(vchiq_susp_log_level, "%s %s "
2286 					"wait for resume blocker interrupted",
2287 					__func__, entity);
2288 				ret = VCHIQ_ERROR;
2289 				write_lock_bh(&arm_state->susp_res_lock);
2290 				arm_state->blocked_count--;
2291 				write_unlock_bh(&arm_state->susp_res_lock);
2292 				goto out;
2293 			}
2294 			vchiq_log_info(vchiq_susp_log_level, "%s %s resume "
2295 				"unblocked", __func__, entity);
2296 			write_lock_bh(&arm_state->susp_res_lock);
2297 			if (--arm_state->blocked_count == 0)
2298 				complete_all(&arm_state->blocked_blocker);
2299 		}
2300 	}
2301 
2302 	stop_suspend_timer(arm_state);
2303 
2304 	local_uc = ++arm_state->videocore_use_count;
2305 	local_entity_uc = ++(*entity_uc);
2306 
2307 	/* If there's a pending request which hasn't yet been serviced then
2308 	 * just clear it.  If we're past VC_SUSPEND_REQUESTED state then
2309 	 * vc_resume_complete will block until we either resume or fail to
2310 	 * suspend */
2311 	if (arm_state->vc_suspend_state <= VC_SUSPEND_REQUESTED)
2312 		set_suspend_state(arm_state, VC_SUSPEND_IDLE);
2313 
2314 	if ((use_type != USE_TYPE_SERVICE_NO_RESUME) && need_resume(state)) {
2315 		set_resume_state(arm_state, VC_RESUME_REQUESTED);
2316 		vchiq_log_info(vchiq_susp_log_level,
2317 			"%s %s count %d, state count %d",
2318 			__func__, entity, local_entity_uc, local_uc);
2319 		request_poll(state, NULL, 0);
2320 	} else
2321 		vchiq_log_trace(vchiq_susp_log_level,
2322 			"%s %s count %d, state count %d",
2323 			__func__, entity, *entity_uc, local_uc);
2324 
2325 
2326 	write_unlock_bh(&arm_state->susp_res_lock);
2327 
2328 	/* Completion is in a done state when we're not suspended, so this won't
2329 	 * block for the non-suspended case. */
2330 	if (!try_wait_for_completion(&arm_state->vc_resume_complete)) {
2331 		vchiq_log_info(vchiq_susp_log_level, "%s %s wait for resume",
2332 			__func__, entity);
2333 		if (wait_for_completion_killable(
2334 				&arm_state->vc_resume_complete) != 0) {
2335 			vchiq_log_error(vchiq_susp_log_level, "%s %s wait for "
2336 				"resume interrupted", __func__, entity);
2337 			ret = VCHIQ_ERROR;
2338 			goto out;
2339 		}
2340 		vchiq_log_info(vchiq_susp_log_level, "%s %s resumed", __func__,
2341 			entity);
2342 	}
2343 
2344 	if (ret == VCHIQ_SUCCESS) {
2345 		VCHIQ_STATUS_T status = VCHIQ_SUCCESS;
2346 		long ack_cnt = atomic_xchg(&arm_state->ka_use_ack_count, 0);
2347 		while (ack_cnt && (status == VCHIQ_SUCCESS)) {
2348 			/* Send the use notify to videocore */
2349 			status = vchiq_send_remote_use_active(state);
2350 			if (status == VCHIQ_SUCCESS)
2351 				ack_cnt--;
2352 			else
2353 				atomic_add(ack_cnt,
2354 					&arm_state->ka_use_ack_count);
2355 		}
2356 	}
2357 
2358 out:
2359 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2360 	return ret;
2361 }
2362 
2363 VCHIQ_STATUS_T
2364 vchiq_release_internal(VCHIQ_STATE_T *state, VCHIQ_SERVICE_T *service)
2365 {
2366 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2367 	VCHIQ_STATUS_T ret = VCHIQ_SUCCESS;
2368 	char entity[16];
2369 	int *entity_uc;
2370 
2371 	if (!arm_state)
2372 		goto out;
2373 
2374 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2375 
2376 	if (service) {
2377 		snprintf(entity, sizeof(entity), "%c%c%c%c:%8x",
2378 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2379 			service->client_id);
2380 		entity_uc = &service->service_use_count;
2381 	} else {
2382 		snprintf(entity, sizeof(entity), "PEER:   ");
2383 		entity_uc = &arm_state->peer_use_count;
2384 	}
2385 
2386 	write_lock_bh(&arm_state->susp_res_lock);
2387 	if (!arm_state->videocore_use_count || !(*entity_uc)) {
2388 		/* Don't use BUG_ON - don't allow user thread to crash kernel */
2389 		WARN_ON(!arm_state->videocore_use_count);
2390 		WARN_ON(!(*entity_uc));
2391 		ret = VCHIQ_ERROR;
2392 		goto unlock;
2393 	}
2394 	--arm_state->videocore_use_count;
2395 	--(*entity_uc);
2396 
2397 	if (!vchiq_videocore_wanted(state)) {
2398 		if (vchiq_platform_use_suspend_timer() &&
2399 				!arm_state->resume_blocked) {
2400 			/* Only use the timer if we're not trying to force
2401 			 * suspend (=> resume_blocked) */
2402 			start_suspend_timer(arm_state);
2403 		} else {
2404 			vchiq_log_info(vchiq_susp_log_level,
2405 				"%s %s count %d, state count %d - suspending",
2406 				__func__, entity, *entity_uc,
2407 				arm_state->videocore_use_count);
2408 			vchiq_arm_vcsuspend(state);
2409 		}
2410 	} else
2411 		vchiq_log_trace(vchiq_susp_log_level,
2412 			"%s %s count %d, state count %d",
2413 			__func__, entity, *entity_uc,
2414 			arm_state->videocore_use_count);
2415 
2416 unlock:
2417 	write_unlock_bh(&arm_state->susp_res_lock);
2418 
2419 out:
2420 	vchiq_log_trace(vchiq_susp_log_level, "%s exit %d", __func__, ret);
2421 	return ret;
2422 }
2423 
2424 void
2425 vchiq_on_remote_use(VCHIQ_STATE_T *state)
2426 {
2427 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2428 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2429 	atomic_inc(&arm_state->ka_use_count);
2430 	complete(&arm_state->ka_evt);
2431 }
2432 
2433 void
2434 vchiq_on_remote_release(VCHIQ_STATE_T *state)
2435 {
2436 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2437 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2438 	atomic_inc(&arm_state->ka_release_count);
2439 	complete(&arm_state->ka_evt);
2440 }
2441 
2442 VCHIQ_STATUS_T
2443 vchiq_use_service_internal(VCHIQ_SERVICE_T *service)
2444 {
2445 	return vchiq_use_internal(service->state, service, USE_TYPE_SERVICE);
2446 }
2447 
2448 VCHIQ_STATUS_T
2449 vchiq_release_service_internal(VCHIQ_SERVICE_T *service)
2450 {
2451 	return vchiq_release_internal(service->state, service);
2452 }
2453 
2454 static void suspend_timer_callback(unsigned long context)
2455 {
2456 	VCHIQ_STATE_T *state = (VCHIQ_STATE_T *)context;
2457 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2458 	if (!arm_state)
2459 		goto out;
2460 	vchiq_log_info(vchiq_susp_log_level,
2461 		"%s - suspend timer expired - check suspend", __func__);
2462 	vchiq_check_suspend(state);
2463 out:
2464 	return;
2465 }
2466 
2467 VCHIQ_STATUS_T
2468 vchiq_use_service_no_resume(VCHIQ_SERVICE_HANDLE_T handle)
2469 {
2470 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2471 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2472 	if (service) {
2473 		ret = vchiq_use_internal(service->state, service,
2474 				USE_TYPE_SERVICE_NO_RESUME);
2475 		unlock_service(service);
2476 	}
2477 	return ret;
2478 }
2479 
2480 VCHIQ_STATUS_T
2481 vchiq_use_service(VCHIQ_SERVICE_HANDLE_T handle)
2482 {
2483 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2484 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2485 	if (service) {
2486 		ret = vchiq_use_internal(service->state, service,
2487 				USE_TYPE_SERVICE);
2488 		unlock_service(service);
2489 	}
2490 	return ret;
2491 }
2492 
2493 VCHIQ_STATUS_T
2494 vchiq_release_service(VCHIQ_SERVICE_HANDLE_T handle)
2495 {
2496 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2497 	VCHIQ_SERVICE_T *service = find_service_by_handle(handle);
2498 	if (service) {
2499 		ret = vchiq_release_internal(service->state, service);
2500 		unlock_service(service);
2501 	}
2502 	return ret;
2503 }
2504 
2505 void
2506 vchiq_dump_service_use_state(VCHIQ_STATE_T *state)
2507 {
2508 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2509 	int i, j = 0;
2510 	/* Only dump 64 services */
2511 	static const int local_max_services = 64;
2512 	/* If there's more than 64 services, only dump ones with
2513 	 * non-zero counts */
2514 	int only_nonzero = 0;
2515 	static const char *nz = "<-- preventing suspend";
2516 
2517 	enum vc_suspend_status vc_suspend_state;
2518 	enum vc_resume_status  vc_resume_state;
2519 	int peer_count;
2520 	int vc_use_count;
2521 	int active_services;
2522 	struct service_data_struct {
2523 		int fourcc;
2524 		int clientid;
2525 		int use_count;
2526 	} service_data[local_max_services];
2527 
2528 	if (!arm_state)
2529 		return;
2530 
2531 	read_lock_bh(&arm_state->susp_res_lock);
2532 	vc_suspend_state = arm_state->vc_suspend_state;
2533 	vc_resume_state  = arm_state->vc_resume_state;
2534 	peer_count = arm_state->peer_use_count;
2535 	vc_use_count = arm_state->videocore_use_count;
2536 	active_services = state->unused_service;
2537 	if (active_services > local_max_services)
2538 		only_nonzero = 1;
2539 
2540 	for (i = 0; (i < active_services) && (j < local_max_services); i++) {
2541 		VCHIQ_SERVICE_T *service_ptr = state->services[i];
2542 		if (!service_ptr)
2543 			continue;
2544 
2545 		if (only_nonzero && !service_ptr->service_use_count)
2546 			continue;
2547 
2548 		if (service_ptr->srvstate != VCHIQ_SRVSTATE_FREE) {
2549 			service_data[j].fourcc = service_ptr->base.fourcc;
2550 			service_data[j].clientid = service_ptr->client_id;
2551 			service_data[j++].use_count = service_ptr->
2552 							service_use_count;
2553 		}
2554 	}
2555 
2556 	read_unlock_bh(&arm_state->susp_res_lock);
2557 
2558 	vchiq_log_warning(vchiq_susp_log_level,
2559 		"-- Videcore suspend state: %s --",
2560 		suspend_state_names[vc_suspend_state + VC_SUSPEND_NUM_OFFSET]);
2561 	vchiq_log_warning(vchiq_susp_log_level,
2562 		"-- Videcore resume state: %s --",
2563 		resume_state_names[vc_resume_state + VC_RESUME_NUM_OFFSET]);
2564 
2565 	if (only_nonzero)
2566 		vchiq_log_warning(vchiq_susp_log_level, "Too many active "
2567 			"services (%d).  Only dumping up to first %d services "
2568 			"with non-zero use-count", active_services,
2569 			local_max_services);
2570 
2571 	for (i = 0; i < j; i++) {
2572 		vchiq_log_warning(vchiq_susp_log_level,
2573 			"----- %c%c%c%c:%d service count %d %s",
2574 			VCHIQ_FOURCC_AS_4CHARS(service_data[i].fourcc),
2575 			service_data[i].clientid,
2576 			service_data[i].use_count,
2577 			service_data[i].use_count ? nz : "");
2578 	}
2579 	vchiq_log_warning(vchiq_susp_log_level,
2580 		"----- VCHIQ use count count %d", peer_count);
2581 	vchiq_log_warning(vchiq_susp_log_level,
2582 		"--- Overall vchiq instance use count %d", vc_use_count);
2583 
2584 	vchiq_dump_platform_use_state(state);
2585 }
2586 
2587 VCHIQ_STATUS_T
2588 vchiq_check_service(VCHIQ_SERVICE_T *service)
2589 {
2590 	VCHIQ_ARM_STATE_T *arm_state;
2591 	VCHIQ_STATUS_T ret = VCHIQ_ERROR;
2592 
2593 	if (!service || !service->state)
2594 		goto out;
2595 
2596 	vchiq_log_trace(vchiq_susp_log_level, "%s", __func__);
2597 
2598 	arm_state = vchiq_platform_get_arm_state(service->state);
2599 
2600 	read_lock_bh(&arm_state->susp_res_lock);
2601 	if (service->service_use_count)
2602 		ret = VCHIQ_SUCCESS;
2603 	read_unlock_bh(&arm_state->susp_res_lock);
2604 
2605 	if (ret == VCHIQ_ERROR) {
2606 		vchiq_log_error(vchiq_susp_log_level,
2607 			"%s ERROR - %c%c%c%c:%8x service count %d, "
2608 			"state count %d, videocore suspend state %s", __func__,
2609 			VCHIQ_FOURCC_AS_4CHARS(service->base.fourcc),
2610 			service->client_id, service->service_use_count,
2611 			arm_state->videocore_use_count,
2612 			suspend_state_names[arm_state->vc_suspend_state +
2613 						VC_SUSPEND_NUM_OFFSET]);
2614 		vchiq_dump_service_use_state(service->state);
2615 	}
2616 out:
2617 	return ret;
2618 }
2619 
2620 /* stub functions */
2621 void vchiq_on_remote_use_active(VCHIQ_STATE_T *state)
2622 {
2623 	(void)state;
2624 }
2625 
2626 void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
2627 	VCHIQ_CONNSTATE_T oldstate, VCHIQ_CONNSTATE_T newstate)
2628 {
2629 	VCHIQ_ARM_STATE_T *arm_state = vchiq_platform_get_arm_state(state);
2630 	vchiq_log_info(vchiq_susp_log_level, "%d: %s->%s", state->id,
2631 		get_conn_state_name(oldstate), get_conn_state_name(newstate));
2632 	if (state->conn_state == VCHIQ_CONNSTATE_CONNECTED) {
2633 		write_lock_bh(&arm_state->susp_res_lock);
2634 		if (!arm_state->first_connect) {
2635 			char threadname[10];
2636 			arm_state->first_connect = 1;
2637 			write_unlock_bh(&arm_state->susp_res_lock);
2638 			snprintf(threadname, sizeof(threadname), "VCHIQka-%d",
2639 				state->id);
2640 			arm_state->ka_thread = vchiq_thread_create(
2641 				&vchiq_keepalive_thread_func,
2642 				(void *)state,
2643 				threadname);
2644 			if (arm_state->ka_thread == NULL) {
2645 				vchiq_log_error(vchiq_susp_log_level,
2646 					"vchiq: FATAL: couldn't create thread %s",
2647 					threadname);
2648 			} else {
2649 				wake_up_process(arm_state->ka_thread);
2650 			}
2651 		} else
2652 			write_unlock_bh(&arm_state->susp_res_lock);
2653 	}
2654 }
2655 
2656 /****************************************************************************
2657 *
2658 *   vchiq_init - called when the module is loaded.
2659 *
2660 ***************************************************************************/
2661 
2662 int __init vchiq_init(void);
2663 int __init
2664 vchiq_init(void)
2665 {
2666 	int err;
2667 
2668 #ifdef notyet
2669 	/* create proc entries */
2670 	err = vchiq_proc_init();
2671 	if (err != 0)
2672 		goto failed_proc_init;
2673 #endif
2674 
2675 	spin_lock_init(&msg_queue_spinlock);
2676 
2677 	err = vchiq_platform_init(&g_state);
2678 	if (err != 0)
2679 		goto failed_platform_init;
2680 
2681 	vchiq_log_info(vchiq_arm_log_level,
2682 		"vchiq: initialised - version %d (min %d)",
2683 		VCHIQ_VERSION, VCHIQ_VERSION_MIN);
2684 
2685 	return 0;
2686 
2687 failed_platform_init:
2688 	vchiq_log_warning(vchiq_arm_log_level, "could not load vchiq");
2689 	return err;
2690 }
2691 
2692 #ifdef notyet
2693 static int vchiq_instance_get_use_count(VCHIQ_INSTANCE_T instance)
2694 {
2695 	VCHIQ_SERVICE_T *service;
2696 	int use_count = 0, i;
2697 	i = 0;
2698 	while ((service = next_service_by_instance(instance->state,
2699 		instance, &i)) != NULL) {
2700 		use_count += service->service_use_count;
2701 		unlock_service(service);
2702 	}
2703 	return use_count;
2704 }
2705 
2706 /* read the per-process use-count */
2707 static int proc_read_use_count(char *page, char **start,
2708 			       off_t off, int count,
2709 			       int *eof, void *data)
2710 {
2711 	VCHIQ_INSTANCE_T instance = data;
2712 	int len, use_count;
2713 
2714 	use_count = vchiq_instance_get_use_count(instance);
2715 	len = snprintf(page+off, count, "%d\n", use_count);
2716 
2717 	return len;
2718 }
2719 
2720 /* add an instance (process) to the proc entries */
2721 static int vchiq_proc_add_instance(VCHIQ_INSTANCE_T instance)
2722 {
2723 	char pidstr[32];
2724 	struct proc_dir_entry *top, *use_count;
2725 	struct proc_dir_entry *clients = vchiq_clients_top();
2726 	int pid = instance->pid;
2727 
2728 	snprintf(pidstr, sizeof(pidstr), "%d", pid);
2729 	top = proc_mkdir(pidstr, clients);
2730 	if (!top)
2731 		goto fail_top;
2732 
2733 	use_count = create_proc_read_entry("use_count",
2734 					   0444, top,
2735 					   proc_read_use_count,
2736 					   instance);
2737 	if (!use_count)
2738 		goto fail_use_count;
2739 
2740 	instance->proc_entry = top;
2741 
2742 	return 0;
2743 
2744 fail_use_count:
2745 	remove_proc_entry(top->name, clients);
2746 fail_top:
2747 	return -ENOMEM;
2748 }
2749 
2750 static void vchiq_proc_remove_instance(VCHIQ_INSTANCE_T instance)
2751 {
2752 	struct proc_dir_entry *clients = vchiq_clients_top();
2753 	remove_proc_entry("use_count", instance->proc_entry);
2754 	remove_proc_entry(instance->proc_entry->name, clients);
2755 }
2756 
2757 #endif
2758 
2759 /****************************************************************************
2760 *
2761 *   vchiq_exit - called when the module is unloaded.
2762 *
2763 ***************************************************************************/
2764 
2765 void vchiq_exit(void);
2766 void
2767 vchiq_exit(void)
2768 {
2769 	vchiq_platform_exit(&g_state);
2770 }
2771