1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Remote Processor Framework
4  *
5  * Copyright (C) 2011 Texas Instruments, Inc.
6  * Copyright (C) 2011 Google, Inc.
7  *
8  * Ohad Ben-Cohen <ohad@wizery.com>
9  * Brian Swetland <swetland@google.com>
10  * Mark Grosen <mgrosen@ti.com>
11  * Fernando Guzman Lugo <fernando.lugo@ti.com>
12  * Suman Anna <s-anna@ti.com>
13  * Robert Tivy <rtivy@ti.com>
14  * Armando Uribe De Leon <x0095078@ti.com>
15  */
16 
17 #define pr_fmt(fmt)    "%s: " fmt, __func__
18 
19 #include <linux/delay.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/panic_notifier.h>
24 #include <linux/slab.h>
25 #include <linux/mutex.h>
26 #include <linux/dma-map-ops.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/dma-direct.h> /* XXX: pokes into bus_dma_range */
29 #include <linux/firmware.h>
30 #include <linux/string.h>
31 #include <linux/debugfs.h>
32 #include <linux/rculist.h>
33 #include <linux/remoteproc.h>
34 #include <linux/iommu.h>
35 #include <linux/idr.h>
36 #include <linux/elf.h>
37 #include <linux/crc32.h>
38 #include <linux/of_reserved_mem.h>
39 #include <linux/virtio_ids.h>
40 #include <linux/virtio_ring.h>
41 #include <asm/byteorder.h>
42 #include <linux/platform_device.h>
43 
44 #include "remoteproc_internal.h"
45 
46 #define HIGH_BITS_MASK 0xFFFFFFFF00000000ULL
47 
48 static DEFINE_MUTEX(rproc_list_mutex);
49 static LIST_HEAD(rproc_list);
50 static struct notifier_block rproc_panic_nb;
51 
52 typedef int (*rproc_handle_resource_t)(struct rproc *rproc,
53 				 void *, int offset, int avail);
54 
55 static int rproc_alloc_carveout(struct rproc *rproc,
56 				struct rproc_mem_entry *mem);
57 static int rproc_release_carveout(struct rproc *rproc,
58 				  struct rproc_mem_entry *mem);
59 
60 /* Unique indices for remoteproc devices */
61 static DEFINE_IDA(rproc_dev_index);
62 
63 static const char * const rproc_crash_names[] = {
64 	[RPROC_MMUFAULT]	= "mmufault",
65 	[RPROC_WATCHDOG]	= "watchdog",
66 	[RPROC_FATAL_ERROR]	= "fatal error",
67 };
68 
69 /* translate rproc_crash_type to string */
70 static const char *rproc_crash_to_string(enum rproc_crash_type type)
71 {
72 	if (type < ARRAY_SIZE(rproc_crash_names))
73 		return rproc_crash_names[type];
74 	return "unknown";
75 }
76 
77 /*
78  * This is the IOMMU fault handler we register with the IOMMU API
79  * (when relevant; not all remote processors access memory through
80  * an IOMMU).
81  *
82  * IOMMU core will invoke this handler whenever the remote processor
83  * will try to access an unmapped device address.
84  */
85 static int rproc_iommu_fault(struct iommu_domain *domain, struct device *dev,
86 			     unsigned long iova, int flags, void *token)
87 {
88 	struct rproc *rproc = token;
89 
90 	dev_err(dev, "iommu fault: da 0x%lx flags 0x%x\n", iova, flags);
91 
92 	rproc_report_crash(rproc, RPROC_MMUFAULT);
93 
94 	/*
95 	 * Let the iommu core know we're not really handling this fault;
96 	 * we just used it as a recovery trigger.
97 	 */
98 	return -ENOSYS;
99 }
100 
101 static int rproc_enable_iommu(struct rproc *rproc)
102 {
103 	struct iommu_domain *domain;
104 	struct device *dev = rproc->dev.parent;
105 	int ret;
106 
107 	if (!rproc->has_iommu) {
108 		dev_dbg(dev, "iommu not present\n");
109 		return 0;
110 	}
111 
112 	domain = iommu_domain_alloc(dev->bus);
113 	if (!domain) {
114 		dev_err(dev, "can't alloc iommu domain\n");
115 		return -ENOMEM;
116 	}
117 
118 	iommu_set_fault_handler(domain, rproc_iommu_fault, rproc);
119 
120 	ret = iommu_attach_device(domain, dev);
121 	if (ret) {
122 		dev_err(dev, "can't attach iommu device: %d\n", ret);
123 		goto free_domain;
124 	}
125 
126 	rproc->domain = domain;
127 
128 	return 0;
129 
130 free_domain:
131 	iommu_domain_free(domain);
132 	return ret;
133 }
134 
135 static void rproc_disable_iommu(struct rproc *rproc)
136 {
137 	struct iommu_domain *domain = rproc->domain;
138 	struct device *dev = rproc->dev.parent;
139 
140 	if (!domain)
141 		return;
142 
143 	iommu_detach_device(domain, dev);
144 	iommu_domain_free(domain);
145 }
146 
147 phys_addr_t rproc_va_to_pa(void *cpu_addr)
148 {
149 	/*
150 	 * Return physical address according to virtual address location
151 	 * - in vmalloc: if region ioremapped or defined as dma_alloc_coherent
152 	 * - in kernel: if region allocated in generic dma memory pool
153 	 */
154 	if (is_vmalloc_addr(cpu_addr)) {
155 		return page_to_phys(vmalloc_to_page(cpu_addr)) +
156 				    offset_in_page(cpu_addr);
157 	}
158 
159 	WARN_ON(!virt_addr_valid(cpu_addr));
160 	return virt_to_phys(cpu_addr);
161 }
162 EXPORT_SYMBOL(rproc_va_to_pa);
163 
164 /**
165  * rproc_da_to_va() - lookup the kernel virtual address for a remoteproc address
166  * @rproc: handle of a remote processor
167  * @da: remoteproc device address to translate
168  * @len: length of the memory region @da is pointing to
169  * @is_iomem: optional pointer filled in to indicate if @da is iomapped memory
170  *
171  * Some remote processors will ask us to allocate them physically contiguous
172  * memory regions (which we call "carveouts"), and map them to specific
173  * device addresses (which are hardcoded in the firmware). They may also have
174  * dedicated memory regions internal to the processors, and use them either
175  * exclusively or alongside carveouts.
176  *
177  * They may then ask us to copy objects into specific device addresses (e.g.
178  * code/data sections) or expose us certain symbols in other device address
179  * (e.g. their trace buffer).
180  *
181  * This function is a helper function with which we can go over the allocated
182  * carveouts and translate specific device addresses to kernel virtual addresses
183  * so we can access the referenced memory. This function also allows to perform
184  * translations on the internal remoteproc memory regions through a platform
185  * implementation specific da_to_va ops, if present.
186  *
187  * Note: phys_to_virt(iommu_iova_to_phys(rproc->domain, da)) will work too,
188  * but only on kernel direct mapped RAM memory. Instead, we're just using
189  * here the output of the DMA API for the carveouts, which should be more
190  * correct.
191  *
192  * Return: a valid kernel address on success or NULL on failure
193  */
194 void *rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool *is_iomem)
195 {
196 	struct rproc_mem_entry *carveout;
197 	void *ptr = NULL;
198 
199 	if (rproc->ops->da_to_va) {
200 		ptr = rproc->ops->da_to_va(rproc, da, len, is_iomem);
201 		if (ptr)
202 			goto out;
203 	}
204 
205 	list_for_each_entry(carveout, &rproc->carveouts, node) {
206 		int offset = da - carveout->da;
207 
208 		/*  Verify that carveout is allocated */
209 		if (!carveout->va)
210 			continue;
211 
212 		/* try next carveout if da is too small */
213 		if (offset < 0)
214 			continue;
215 
216 		/* try next carveout if da is too large */
217 		if (offset + len > carveout->len)
218 			continue;
219 
220 		ptr = carveout->va + offset;
221 
222 		if (is_iomem)
223 			*is_iomem = carveout->is_iomem;
224 
225 		break;
226 	}
227 
228 out:
229 	return ptr;
230 }
231 EXPORT_SYMBOL(rproc_da_to_va);
232 
233 /**
234  * rproc_find_carveout_by_name() - lookup the carveout region by a name
235  * @rproc: handle of a remote processor
236  * @name: carveout name to find (format string)
237  * @...: optional parameters matching @name string
238  *
239  * Platform driver has the capability to register some pre-allacoted carveout
240  * (physically contiguous memory regions) before rproc firmware loading and
241  * associated resource table analysis. These regions may be dedicated memory
242  * regions internal to the coprocessor or specified DDR region with specific
243  * attributes
244  *
245  * This function is a helper function with which we can go over the
246  * allocated carveouts and return associated region characteristics like
247  * coprocessor address, length or processor virtual address.
248  *
249  * Return: a valid pointer on carveout entry on success or NULL on failure.
250  */
251 __printf(2, 3)
252 struct rproc_mem_entry *
253 rproc_find_carveout_by_name(struct rproc *rproc, const char *name, ...)
254 {
255 	va_list args;
256 	char _name[32];
257 	struct rproc_mem_entry *carveout, *mem = NULL;
258 
259 	if (!name)
260 		return NULL;
261 
262 	va_start(args, name);
263 	vsnprintf(_name, sizeof(_name), name, args);
264 	va_end(args);
265 
266 	list_for_each_entry(carveout, &rproc->carveouts, node) {
267 		/* Compare carveout and requested names */
268 		if (!strcmp(carveout->name, _name)) {
269 			mem = carveout;
270 			break;
271 		}
272 	}
273 
274 	return mem;
275 }
276 
277 /**
278  * rproc_check_carveout_da() - Check specified carveout da configuration
279  * @rproc: handle of a remote processor
280  * @mem: pointer on carveout to check
281  * @da: area device address
282  * @len: associated area size
283  *
284  * This function is a helper function to verify requested device area (couple
285  * da, len) is part of specified carveout.
286  * If da is not set (defined as FW_RSC_ADDR_ANY), only requested length is
287  * checked.
288  *
289  * Return: 0 if carveout matches request else error
290  */
291 static int rproc_check_carveout_da(struct rproc *rproc,
292 				   struct rproc_mem_entry *mem, u32 da, u32 len)
293 {
294 	struct device *dev = &rproc->dev;
295 	int delta;
296 
297 	/* Check requested resource length */
298 	if (len > mem->len) {
299 		dev_err(dev, "Registered carveout doesn't fit len request\n");
300 		return -EINVAL;
301 	}
302 
303 	if (da != FW_RSC_ADDR_ANY && mem->da == FW_RSC_ADDR_ANY) {
304 		/* Address doesn't match registered carveout configuration */
305 		return -EINVAL;
306 	} else if (da != FW_RSC_ADDR_ANY && mem->da != FW_RSC_ADDR_ANY) {
307 		delta = da - mem->da;
308 
309 		/* Check requested resource belongs to registered carveout */
310 		if (delta < 0) {
311 			dev_err(dev,
312 				"Registered carveout doesn't fit da request\n");
313 			return -EINVAL;
314 		}
315 
316 		if (delta + len > mem->len) {
317 			dev_err(dev,
318 				"Registered carveout doesn't fit len request\n");
319 			return -EINVAL;
320 		}
321 	}
322 
323 	return 0;
324 }
325 
326 int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
327 {
328 	struct rproc *rproc = rvdev->rproc;
329 	struct device *dev = &rproc->dev;
330 	struct rproc_vring *rvring = &rvdev->vring[i];
331 	struct fw_rsc_vdev *rsc;
332 	int ret, notifyid;
333 	struct rproc_mem_entry *mem;
334 	size_t size;
335 
336 	/* actual size of vring (in bytes) */
337 	size = PAGE_ALIGN(vring_size(rvring->len, rvring->align));
338 
339 	rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
340 
341 	/* Search for pre-registered carveout */
342 	mem = rproc_find_carveout_by_name(rproc, "vdev%dvring%d", rvdev->index,
343 					  i);
344 	if (mem) {
345 		if (rproc_check_carveout_da(rproc, mem, rsc->vring[i].da, size))
346 			return -ENOMEM;
347 	} else {
348 		/* Register carveout in in list */
349 		mem = rproc_mem_entry_init(dev, NULL, 0,
350 					   size, rsc->vring[i].da,
351 					   rproc_alloc_carveout,
352 					   rproc_release_carveout,
353 					   "vdev%dvring%d",
354 					   rvdev->index, i);
355 		if (!mem) {
356 			dev_err(dev, "Can't allocate memory entry structure\n");
357 			return -ENOMEM;
358 		}
359 
360 		rproc_add_carveout(rproc, mem);
361 	}
362 
363 	/*
364 	 * Assign an rproc-wide unique index for this vring
365 	 * TODO: assign a notifyid for rvdev updates as well
366 	 * TODO: support predefined notifyids (via resource table)
367 	 */
368 	ret = idr_alloc(&rproc->notifyids, rvring, 0, 0, GFP_KERNEL);
369 	if (ret < 0) {
370 		dev_err(dev, "idr_alloc failed: %d\n", ret);
371 		return ret;
372 	}
373 	notifyid = ret;
374 
375 	/* Potentially bump max_notifyid */
376 	if (notifyid > rproc->max_notifyid)
377 		rproc->max_notifyid = notifyid;
378 
379 	rvring->notifyid = notifyid;
380 
381 	/* Let the rproc know the notifyid of this vring.*/
382 	rsc->vring[i].notifyid = notifyid;
383 	return 0;
384 }
385 
386 static int
387 rproc_parse_vring(struct rproc_vdev *rvdev, struct fw_rsc_vdev *rsc, int i)
388 {
389 	struct rproc *rproc = rvdev->rproc;
390 	struct device *dev = &rproc->dev;
391 	struct fw_rsc_vdev_vring *vring = &rsc->vring[i];
392 	struct rproc_vring *rvring = &rvdev->vring[i];
393 
394 	dev_dbg(dev, "vdev rsc: vring%d: da 0x%x, qsz %d, align %d\n",
395 		i, vring->da, vring->num, vring->align);
396 
397 	/* verify queue size and vring alignment are sane */
398 	if (!vring->num || !vring->align) {
399 		dev_err(dev, "invalid qsz (%d) or alignment (%d)\n",
400 			vring->num, vring->align);
401 		return -EINVAL;
402 	}
403 
404 	rvring->len = vring->num;
405 	rvring->align = vring->align;
406 	rvring->rvdev = rvdev;
407 
408 	return 0;
409 }
410 
411 void rproc_free_vring(struct rproc_vring *rvring)
412 {
413 	struct rproc *rproc = rvring->rvdev->rproc;
414 	int idx = rvring - rvring->rvdev->vring;
415 	struct fw_rsc_vdev *rsc;
416 
417 	idr_remove(&rproc->notifyids, rvring->notifyid);
418 
419 	/*
420 	 * At this point rproc_stop() has been called and the installed resource
421 	 * table in the remote processor memory may no longer be accessible. As
422 	 * such and as per rproc_stop(), rproc->table_ptr points to the cached
423 	 * resource table (rproc->cached_table).  The cached resource table is
424 	 * only available when a remote processor has been booted by the
425 	 * remoteproc core, otherwise it is NULL.
426 	 *
427 	 * Based on the above, reset the virtio device section in the cached
428 	 * resource table only if there is one to work with.
429 	 */
430 	if (rproc->table_ptr) {
431 		rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset;
432 		rsc->vring[idx].da = 0;
433 		rsc->vring[idx].notifyid = -1;
434 	}
435 }
436 
437 static int rproc_vdev_do_start(struct rproc_subdev *subdev)
438 {
439 	struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
440 
441 	return rproc_add_virtio_dev(rvdev, rvdev->id);
442 }
443 
444 static void rproc_vdev_do_stop(struct rproc_subdev *subdev, bool crashed)
445 {
446 	struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
447 	int ret;
448 
449 	ret = device_for_each_child(&rvdev->dev, NULL, rproc_remove_virtio_dev);
450 	if (ret)
451 		dev_warn(&rvdev->dev, "can't remove vdev child device: %d\n", ret);
452 }
453 
454 /**
455  * rproc_rvdev_release() - release the existence of a rvdev
456  *
457  * @dev: the subdevice's dev
458  */
459 static void rproc_rvdev_release(struct device *dev)
460 {
461 	struct rproc_vdev *rvdev = container_of(dev, struct rproc_vdev, dev);
462 
463 	of_reserved_mem_device_release(dev);
464 
465 	kfree(rvdev);
466 }
467 
468 static int copy_dma_range_map(struct device *to, struct device *from)
469 {
470 	const struct bus_dma_region *map = from->dma_range_map, *new_map, *r;
471 	int num_ranges = 0;
472 
473 	if (!map)
474 		return 0;
475 
476 	for (r = map; r->size; r++)
477 		num_ranges++;
478 
479 	new_map = kmemdup(map, array_size(num_ranges + 1, sizeof(*map)),
480 			  GFP_KERNEL);
481 	if (!new_map)
482 		return -ENOMEM;
483 	to->dma_range_map = new_map;
484 	return 0;
485 }
486 
487 /**
488  * rproc_handle_vdev() - handle a vdev fw resource
489  * @rproc: the remote processor
490  * @ptr: the vring resource descriptor
491  * @offset: offset of the resource entry
492  * @avail: size of available data (for sanity checking the image)
493  *
494  * This resource entry requests the host to statically register a virtio
495  * device (vdev), and setup everything needed to support it. It contains
496  * everything needed to make it possible: the virtio device id, virtio
497  * device features, vrings information, virtio config space, etc...
498  *
499  * Before registering the vdev, the vrings are allocated from non-cacheable
500  * physically contiguous memory. Currently we only support two vrings per
501  * remote processor (temporary limitation). We might also want to consider
502  * doing the vring allocation only later when ->find_vqs() is invoked, and
503  * then release them upon ->del_vqs().
504  *
505  * Note: @da is currently not really handled correctly: we dynamically
506  * allocate it using the DMA API, ignoring requested hard coded addresses,
507  * and we don't take care of any required IOMMU programming. This is all
508  * going to be taken care of when the generic iommu-based DMA API will be
509  * merged. Meanwhile, statically-addressed iommu-based firmware images should
510  * use RSC_DEVMEM resource entries to map their required @da to the physical
511  * address of their base CMA region (ouch, hacky!).
512  *
513  * Return: 0 on success, or an appropriate error code otherwise
514  */
515 static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
516 			     int offset, int avail)
517 {
518 	struct fw_rsc_vdev *rsc = ptr;
519 	struct device *dev = &rproc->dev;
520 	struct rproc_vdev *rvdev;
521 	int i, ret;
522 	char name[16];
523 
524 	/* make sure resource isn't truncated */
525 	if (struct_size(rsc, vring, rsc->num_of_vrings) + rsc->config_len >
526 			avail) {
527 		dev_err(dev, "vdev rsc is truncated\n");
528 		return -EINVAL;
529 	}
530 
531 	/* make sure reserved bytes are zeroes */
532 	if (rsc->reserved[0] || rsc->reserved[1]) {
533 		dev_err(dev, "vdev rsc has non zero reserved bytes\n");
534 		return -EINVAL;
535 	}
536 
537 	dev_dbg(dev, "vdev rsc: id %d, dfeatures 0x%x, cfg len %d, %d vrings\n",
538 		rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings);
539 
540 	/* we currently support only two vrings per rvdev */
541 	if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) {
542 		dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings);
543 		return -EINVAL;
544 	}
545 
546 	rvdev = kzalloc(sizeof(*rvdev), GFP_KERNEL);
547 	if (!rvdev)
548 		return -ENOMEM;
549 
550 	kref_init(&rvdev->refcount);
551 
552 	rvdev->id = rsc->id;
553 	rvdev->rproc = rproc;
554 	rvdev->index = rproc->nb_vdev++;
555 
556 	/* Initialise vdev subdevice */
557 	snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
558 	rvdev->dev.parent = &rproc->dev;
559 	rvdev->dev.release = rproc_rvdev_release;
560 	dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev->dev.parent), name);
561 	dev_set_drvdata(&rvdev->dev, rvdev);
562 
563 	ret = device_register(&rvdev->dev);
564 	if (ret) {
565 		put_device(&rvdev->dev);
566 		return ret;
567 	}
568 
569 	ret = copy_dma_range_map(&rvdev->dev, rproc->dev.parent);
570 	if (ret)
571 		goto free_rvdev;
572 
573 	/* Make device dma capable by inheriting from parent's capabilities */
574 	set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
575 
576 	ret = dma_coerce_mask_and_coherent(&rvdev->dev,
577 					   dma_get_mask(rproc->dev.parent));
578 	if (ret) {
579 		dev_warn(dev,
580 			 "Failed to set DMA mask %llx. Trying to continue... (%pe)\n",
581 			 dma_get_mask(rproc->dev.parent), ERR_PTR(ret));
582 	}
583 
584 	/* parse the vrings */
585 	for (i = 0; i < rsc->num_of_vrings; i++) {
586 		ret = rproc_parse_vring(rvdev, rsc, i);
587 		if (ret)
588 			goto free_rvdev;
589 	}
590 
591 	/* remember the resource offset*/
592 	rvdev->rsc_offset = offset;
593 
594 	/* allocate the vring resources */
595 	for (i = 0; i < rsc->num_of_vrings; i++) {
596 		ret = rproc_alloc_vring(rvdev, i);
597 		if (ret)
598 			goto unwind_vring_allocations;
599 	}
600 
601 	list_add_tail(&rvdev->node, &rproc->rvdevs);
602 
603 	rvdev->subdev.start = rproc_vdev_do_start;
604 	rvdev->subdev.stop = rproc_vdev_do_stop;
605 
606 	rproc_add_subdev(rproc, &rvdev->subdev);
607 
608 	return 0;
609 
610 unwind_vring_allocations:
611 	for (i--; i >= 0; i--)
612 		rproc_free_vring(&rvdev->vring[i]);
613 free_rvdev:
614 	device_unregister(&rvdev->dev);
615 	return ret;
616 }
617 
618 void rproc_vdev_release(struct kref *ref)
619 {
620 	struct rproc_vdev *rvdev = container_of(ref, struct rproc_vdev, refcount);
621 	struct rproc_vring *rvring;
622 	struct rproc *rproc = rvdev->rproc;
623 	int id;
624 
625 	for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
626 		rvring = &rvdev->vring[id];
627 		rproc_free_vring(rvring);
628 	}
629 
630 	rproc_remove_subdev(rproc, &rvdev->subdev);
631 	list_del(&rvdev->node);
632 	device_unregister(&rvdev->dev);
633 }
634 
635 /**
636  * rproc_handle_trace() - handle a shared trace buffer resource
637  * @rproc: the remote processor
638  * @ptr: the trace resource descriptor
639  * @offset: offset of the resource entry
640  * @avail: size of available data (for sanity checking the image)
641  *
642  * In case the remote processor dumps trace logs into memory,
643  * export it via debugfs.
644  *
645  * Currently, the 'da' member of @rsc should contain the device address
646  * where the remote processor is dumping the traces. Later we could also
647  * support dynamically allocating this address using the generic
648  * DMA API (but currently there isn't a use case for that).
649  *
650  * Return: 0 on success, or an appropriate error code otherwise
651  */
652 static int rproc_handle_trace(struct rproc *rproc, void *ptr,
653 			      int offset, int avail)
654 {
655 	struct fw_rsc_trace *rsc = ptr;
656 	struct rproc_debug_trace *trace;
657 	struct device *dev = &rproc->dev;
658 	char name[15];
659 
660 	if (sizeof(*rsc) > avail) {
661 		dev_err(dev, "trace rsc is truncated\n");
662 		return -EINVAL;
663 	}
664 
665 	/* make sure reserved bytes are zeroes */
666 	if (rsc->reserved) {
667 		dev_err(dev, "trace rsc has non zero reserved bytes\n");
668 		return -EINVAL;
669 	}
670 
671 	trace = kzalloc(sizeof(*trace), GFP_KERNEL);
672 	if (!trace)
673 		return -ENOMEM;
674 
675 	/* set the trace buffer dma properties */
676 	trace->trace_mem.len = rsc->len;
677 	trace->trace_mem.da = rsc->da;
678 
679 	/* set pointer on rproc device */
680 	trace->rproc = rproc;
681 
682 	/* make sure snprintf always null terminates, even if truncating */
683 	snprintf(name, sizeof(name), "trace%d", rproc->num_traces);
684 
685 	/* create the debugfs entry */
686 	trace->tfile = rproc_create_trace_file(name, rproc, trace);
687 	if (!trace->tfile) {
688 		kfree(trace);
689 		return -EINVAL;
690 	}
691 
692 	list_add_tail(&trace->node, &rproc->traces);
693 
694 	rproc->num_traces++;
695 
696 	dev_dbg(dev, "%s added: da 0x%x, len 0x%x\n",
697 		name, rsc->da, rsc->len);
698 
699 	return 0;
700 }
701 
702 /**
703  * rproc_handle_devmem() - handle devmem resource entry
704  * @rproc: remote processor handle
705  * @ptr: the devmem resource entry
706  * @offset: offset of the resource entry
707  * @avail: size of available data (for sanity checking the image)
708  *
709  * Remote processors commonly need to access certain on-chip peripherals.
710  *
711  * Some of these remote processors access memory via an iommu device,
712  * and might require us to configure their iommu before they can access
713  * the on-chip peripherals they need.
714  *
715  * This resource entry is a request to map such a peripheral device.
716  *
717  * These devmem entries will contain the physical address of the device in
718  * the 'pa' member. If a specific device address is expected, then 'da' will
719  * contain it (currently this is the only use case supported). 'len' will
720  * contain the size of the physical region we need to map.
721  *
722  * Currently we just "trust" those devmem entries to contain valid physical
723  * addresses, but this is going to change: we want the implementations to
724  * tell us ranges of physical addresses the firmware is allowed to request,
725  * and not allow firmwares to request access to physical addresses that
726  * are outside those ranges.
727  *
728  * Return: 0 on success, or an appropriate error code otherwise
729  */
730 static int rproc_handle_devmem(struct rproc *rproc, void *ptr,
731 			       int offset, int avail)
732 {
733 	struct fw_rsc_devmem *rsc = ptr;
734 	struct rproc_mem_entry *mapping;
735 	struct device *dev = &rproc->dev;
736 	int ret;
737 
738 	/* no point in handling this resource without a valid iommu domain */
739 	if (!rproc->domain)
740 		return -EINVAL;
741 
742 	if (sizeof(*rsc) > avail) {
743 		dev_err(dev, "devmem rsc is truncated\n");
744 		return -EINVAL;
745 	}
746 
747 	/* make sure reserved bytes are zeroes */
748 	if (rsc->reserved) {
749 		dev_err(dev, "devmem rsc has non zero reserved bytes\n");
750 		return -EINVAL;
751 	}
752 
753 	mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
754 	if (!mapping)
755 		return -ENOMEM;
756 
757 	ret = iommu_map(rproc->domain, rsc->da, rsc->pa, rsc->len, rsc->flags);
758 	if (ret) {
759 		dev_err(dev, "failed to map devmem: %d\n", ret);
760 		goto out;
761 	}
762 
763 	/*
764 	 * We'll need this info later when we'll want to unmap everything
765 	 * (e.g. on shutdown).
766 	 *
767 	 * We can't trust the remote processor not to change the resource
768 	 * table, so we must maintain this info independently.
769 	 */
770 	mapping->da = rsc->da;
771 	mapping->len = rsc->len;
772 	list_add_tail(&mapping->node, &rproc->mappings);
773 
774 	dev_dbg(dev, "mapped devmem pa 0x%x, da 0x%x, len 0x%x\n",
775 		rsc->pa, rsc->da, rsc->len);
776 
777 	return 0;
778 
779 out:
780 	kfree(mapping);
781 	return ret;
782 }
783 
784 /**
785  * rproc_alloc_carveout() - allocated specified carveout
786  * @rproc: rproc handle
787  * @mem: the memory entry to allocate
788  *
789  * This function allocate specified memory entry @mem using
790  * dma_alloc_coherent() as default allocator
791  *
792  * Return: 0 on success, or an appropriate error code otherwise
793  */
794 static int rproc_alloc_carveout(struct rproc *rproc,
795 				struct rproc_mem_entry *mem)
796 {
797 	struct rproc_mem_entry *mapping = NULL;
798 	struct device *dev = &rproc->dev;
799 	dma_addr_t dma;
800 	void *va;
801 	int ret;
802 
803 	va = dma_alloc_coherent(dev->parent, mem->len, &dma, GFP_KERNEL);
804 	if (!va) {
805 		dev_err(dev->parent,
806 			"failed to allocate dma memory: len 0x%zx\n",
807 			mem->len);
808 		return -ENOMEM;
809 	}
810 
811 	dev_dbg(dev, "carveout va %pK, dma %pad, len 0x%zx\n",
812 		va, &dma, mem->len);
813 
814 	if (mem->da != FW_RSC_ADDR_ANY && !rproc->domain) {
815 		/*
816 		 * Check requested da is equal to dma address
817 		 * and print a warn message in case of missalignment.
818 		 * Don't stop rproc_start sequence as coprocessor may
819 		 * build pa to da translation on its side.
820 		 */
821 		if (mem->da != (u32)dma)
822 			dev_warn(dev->parent,
823 				 "Allocated carveout doesn't fit device address request\n");
824 	}
825 
826 	/*
827 	 * Ok, this is non-standard.
828 	 *
829 	 * Sometimes we can't rely on the generic iommu-based DMA API
830 	 * to dynamically allocate the device address and then set the IOMMU
831 	 * tables accordingly, because some remote processors might
832 	 * _require_ us to use hard coded device addresses that their
833 	 * firmware was compiled with.
834 	 *
835 	 * In this case, we must use the IOMMU API directly and map
836 	 * the memory to the device address as expected by the remote
837 	 * processor.
838 	 *
839 	 * Obviously such remote processor devices should not be configured
840 	 * to use the iommu-based DMA API: we expect 'dma' to contain the
841 	 * physical address in this case.
842 	 */
843 	if (mem->da != FW_RSC_ADDR_ANY && rproc->domain) {
844 		mapping = kzalloc(sizeof(*mapping), GFP_KERNEL);
845 		if (!mapping) {
846 			ret = -ENOMEM;
847 			goto dma_free;
848 		}
849 
850 		ret = iommu_map(rproc->domain, mem->da, dma, mem->len,
851 				mem->flags);
852 		if (ret) {
853 			dev_err(dev, "iommu_map failed: %d\n", ret);
854 			goto free_mapping;
855 		}
856 
857 		/*
858 		 * We'll need this info later when we'll want to unmap
859 		 * everything (e.g. on shutdown).
860 		 *
861 		 * We can't trust the remote processor not to change the
862 		 * resource table, so we must maintain this info independently.
863 		 */
864 		mapping->da = mem->da;
865 		mapping->len = mem->len;
866 		list_add_tail(&mapping->node, &rproc->mappings);
867 
868 		dev_dbg(dev, "carveout mapped 0x%x to %pad\n",
869 			mem->da, &dma);
870 	}
871 
872 	if (mem->da == FW_RSC_ADDR_ANY) {
873 		/* Update device address as undefined by requester */
874 		if ((u64)dma & HIGH_BITS_MASK)
875 			dev_warn(dev, "DMA address cast in 32bit to fit resource table format\n");
876 
877 		mem->da = (u32)dma;
878 	}
879 
880 	mem->dma = dma;
881 	mem->va = va;
882 
883 	return 0;
884 
885 free_mapping:
886 	kfree(mapping);
887 dma_free:
888 	dma_free_coherent(dev->parent, mem->len, va, dma);
889 	return ret;
890 }
891 
892 /**
893  * rproc_release_carveout() - release acquired carveout
894  * @rproc: rproc handle
895  * @mem: the memory entry to release
896  *
897  * This function releases specified memory entry @mem allocated via
898  * rproc_alloc_carveout() function by @rproc.
899  *
900  * Return: 0 on success, or an appropriate error code otherwise
901  */
902 static int rproc_release_carveout(struct rproc *rproc,
903 				  struct rproc_mem_entry *mem)
904 {
905 	struct device *dev = &rproc->dev;
906 
907 	/* clean up carveout allocations */
908 	dma_free_coherent(dev->parent, mem->len, mem->va, mem->dma);
909 	return 0;
910 }
911 
912 /**
913  * rproc_handle_carveout() - handle phys contig memory allocation requests
914  * @rproc: rproc handle
915  * @ptr: the resource entry
916  * @offset: offset of the resource entry
917  * @avail: size of available data (for image validation)
918  *
919  * This function will handle firmware requests for allocation of physically
920  * contiguous memory regions.
921  *
922  * These request entries should come first in the firmware's resource table,
923  * as other firmware entries might request placing other data objects inside
924  * these memory regions (e.g. data/code segments, trace resource entries, ...).
925  *
926  * Allocating memory this way helps utilizing the reserved physical memory
927  * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
928  * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
929  * pressure is important; it may have a substantial impact on performance.
930  *
931  * Return: 0 on success, or an appropriate error code otherwise
932  */
933 static int rproc_handle_carveout(struct rproc *rproc,
934 				 void *ptr, int offset, int avail)
935 {
936 	struct fw_rsc_carveout *rsc = ptr;
937 	struct rproc_mem_entry *carveout;
938 	struct device *dev = &rproc->dev;
939 
940 	if (sizeof(*rsc) > avail) {
941 		dev_err(dev, "carveout rsc is truncated\n");
942 		return -EINVAL;
943 	}
944 
945 	/* make sure reserved bytes are zeroes */
946 	if (rsc->reserved) {
947 		dev_err(dev, "carveout rsc has non zero reserved bytes\n");
948 		return -EINVAL;
949 	}
950 
951 	dev_dbg(dev, "carveout rsc: name: %s, da 0x%x, pa 0x%x, len 0x%x, flags 0x%x\n",
952 		rsc->name, rsc->da, rsc->pa, rsc->len, rsc->flags);
953 
954 	/*
955 	 * Check carveout rsc already part of a registered carveout,
956 	 * Search by name, then check the da and length
957 	 */
958 	carveout = rproc_find_carveout_by_name(rproc, rsc->name);
959 
960 	if (carveout) {
961 		if (carveout->rsc_offset != FW_RSC_ADDR_ANY) {
962 			dev_err(dev,
963 				"Carveout already associated to resource table\n");
964 			return -ENOMEM;
965 		}
966 
967 		if (rproc_check_carveout_da(rproc, carveout, rsc->da, rsc->len))
968 			return -ENOMEM;
969 
970 		/* Update memory carveout with resource table info */
971 		carveout->rsc_offset = offset;
972 		carveout->flags = rsc->flags;
973 
974 		return 0;
975 	}
976 
977 	/* Register carveout in in list */
978 	carveout = rproc_mem_entry_init(dev, NULL, 0, rsc->len, rsc->da,
979 					rproc_alloc_carveout,
980 					rproc_release_carveout, rsc->name);
981 	if (!carveout) {
982 		dev_err(dev, "Can't allocate memory entry structure\n");
983 		return -ENOMEM;
984 	}
985 
986 	carveout->flags = rsc->flags;
987 	carveout->rsc_offset = offset;
988 	rproc_add_carveout(rproc, carveout);
989 
990 	return 0;
991 }
992 
993 /**
994  * rproc_add_carveout() - register an allocated carveout region
995  * @rproc: rproc handle
996  * @mem: memory entry to register
997  *
998  * This function registers specified memory entry in @rproc carveouts list.
999  * Specified carveout should have been allocated before registering.
1000  */
1001 void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem)
1002 {
1003 	list_add_tail(&mem->node, &rproc->carveouts);
1004 }
1005 EXPORT_SYMBOL(rproc_add_carveout);
1006 
1007 /**
1008  * rproc_mem_entry_init() - allocate and initialize rproc_mem_entry struct
1009  * @dev: pointer on device struct
1010  * @va: virtual address
1011  * @dma: dma address
1012  * @len: memory carveout length
1013  * @da: device address
1014  * @alloc: memory carveout allocation function
1015  * @release: memory carveout release function
1016  * @name: carveout name
1017  *
1018  * This function allocates a rproc_mem_entry struct and fill it with parameters
1019  * provided by client.
1020  *
1021  * Return: a valid pointer on success, or NULL on failure
1022  */
1023 __printf(8, 9)
1024 struct rproc_mem_entry *
1025 rproc_mem_entry_init(struct device *dev,
1026 		     void *va, dma_addr_t dma, size_t len, u32 da,
1027 		     int (*alloc)(struct rproc *, struct rproc_mem_entry *),
1028 		     int (*release)(struct rproc *, struct rproc_mem_entry *),
1029 		     const char *name, ...)
1030 {
1031 	struct rproc_mem_entry *mem;
1032 	va_list args;
1033 
1034 	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
1035 	if (!mem)
1036 		return mem;
1037 
1038 	mem->va = va;
1039 	mem->dma = dma;
1040 	mem->da = da;
1041 	mem->len = len;
1042 	mem->alloc = alloc;
1043 	mem->release = release;
1044 	mem->rsc_offset = FW_RSC_ADDR_ANY;
1045 	mem->of_resm_idx = -1;
1046 
1047 	va_start(args, name);
1048 	vsnprintf(mem->name, sizeof(mem->name), name, args);
1049 	va_end(args);
1050 
1051 	return mem;
1052 }
1053 EXPORT_SYMBOL(rproc_mem_entry_init);
1054 
1055 /**
1056  * rproc_of_resm_mem_entry_init() - allocate and initialize rproc_mem_entry struct
1057  * from a reserved memory phandle
1058  * @dev: pointer on device struct
1059  * @of_resm_idx: reserved memory phandle index in "memory-region"
1060  * @len: memory carveout length
1061  * @da: device address
1062  * @name: carveout name
1063  *
1064  * This function allocates a rproc_mem_entry struct and fill it with parameters
1065  * provided by client.
1066  *
1067  * Return: a valid pointer on success, or NULL on failure
1068  */
1069 __printf(5, 6)
1070 struct rproc_mem_entry *
1071 rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, size_t len,
1072 			     u32 da, const char *name, ...)
1073 {
1074 	struct rproc_mem_entry *mem;
1075 	va_list args;
1076 
1077 	mem = kzalloc(sizeof(*mem), GFP_KERNEL);
1078 	if (!mem)
1079 		return mem;
1080 
1081 	mem->da = da;
1082 	mem->len = len;
1083 	mem->rsc_offset = FW_RSC_ADDR_ANY;
1084 	mem->of_resm_idx = of_resm_idx;
1085 
1086 	va_start(args, name);
1087 	vsnprintf(mem->name, sizeof(mem->name), name, args);
1088 	va_end(args);
1089 
1090 	return mem;
1091 }
1092 EXPORT_SYMBOL(rproc_of_resm_mem_entry_init);
1093 
1094 /**
1095  * rproc_of_parse_firmware() - parse and return the firmware-name
1096  * @dev: pointer on device struct representing a rproc
1097  * @index: index to use for the firmware-name retrieval
1098  * @fw_name: pointer to a character string, in which the firmware
1099  *           name is returned on success and unmodified otherwise.
1100  *
1101  * This is an OF helper function that parses a device's DT node for
1102  * the "firmware-name" property and returns the firmware name pointer
1103  * in @fw_name on success.
1104  *
1105  * Return: 0 on success, or an appropriate failure.
1106  */
1107 int rproc_of_parse_firmware(struct device *dev, int index, const char **fw_name)
1108 {
1109 	int ret;
1110 
1111 	ret = of_property_read_string_index(dev->of_node, "firmware-name",
1112 					    index, fw_name);
1113 	return ret ? ret : 0;
1114 }
1115 EXPORT_SYMBOL(rproc_of_parse_firmware);
1116 
1117 /*
1118  * A lookup table for resource handlers. The indices are defined in
1119  * enum fw_resource_type.
1120  */
1121 static rproc_handle_resource_t rproc_loading_handlers[RSC_LAST] = {
1122 	[RSC_CARVEOUT] = rproc_handle_carveout,
1123 	[RSC_DEVMEM] = rproc_handle_devmem,
1124 	[RSC_TRACE] = rproc_handle_trace,
1125 	[RSC_VDEV] = rproc_handle_vdev,
1126 };
1127 
1128 /* handle firmware resource entries before booting the remote processor */
1129 static int rproc_handle_resources(struct rproc *rproc,
1130 				  rproc_handle_resource_t handlers[RSC_LAST])
1131 {
1132 	struct device *dev = &rproc->dev;
1133 	rproc_handle_resource_t handler;
1134 	int ret = 0, i;
1135 
1136 	if (!rproc->table_ptr)
1137 		return 0;
1138 
1139 	for (i = 0; i < rproc->table_ptr->num; i++) {
1140 		int offset = rproc->table_ptr->offset[i];
1141 		struct fw_rsc_hdr *hdr = (void *)rproc->table_ptr + offset;
1142 		int avail = rproc->table_sz - offset - sizeof(*hdr);
1143 		void *rsc = (void *)hdr + sizeof(*hdr);
1144 
1145 		/* make sure table isn't truncated */
1146 		if (avail < 0) {
1147 			dev_err(dev, "rsc table is truncated\n");
1148 			return -EINVAL;
1149 		}
1150 
1151 		dev_dbg(dev, "rsc: type %d\n", hdr->type);
1152 
1153 		if (hdr->type >= RSC_VENDOR_START &&
1154 		    hdr->type <= RSC_VENDOR_END) {
1155 			ret = rproc_handle_rsc(rproc, hdr->type, rsc,
1156 					       offset + sizeof(*hdr), avail);
1157 			if (ret == RSC_HANDLED)
1158 				continue;
1159 			else if (ret < 0)
1160 				break;
1161 
1162 			dev_warn(dev, "unsupported vendor resource %d\n",
1163 				 hdr->type);
1164 			continue;
1165 		}
1166 
1167 		if (hdr->type >= RSC_LAST) {
1168 			dev_warn(dev, "unsupported resource %d\n", hdr->type);
1169 			continue;
1170 		}
1171 
1172 		handler = handlers[hdr->type];
1173 		if (!handler)
1174 			continue;
1175 
1176 		ret = handler(rproc, rsc, offset + sizeof(*hdr), avail);
1177 		if (ret)
1178 			break;
1179 	}
1180 
1181 	return ret;
1182 }
1183 
1184 static int rproc_prepare_subdevices(struct rproc *rproc)
1185 {
1186 	struct rproc_subdev *subdev;
1187 	int ret;
1188 
1189 	list_for_each_entry(subdev, &rproc->subdevs, node) {
1190 		if (subdev->prepare) {
1191 			ret = subdev->prepare(subdev);
1192 			if (ret)
1193 				goto unroll_preparation;
1194 		}
1195 	}
1196 
1197 	return 0;
1198 
1199 unroll_preparation:
1200 	list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node) {
1201 		if (subdev->unprepare)
1202 			subdev->unprepare(subdev);
1203 	}
1204 
1205 	return ret;
1206 }
1207 
1208 static int rproc_start_subdevices(struct rproc *rproc)
1209 {
1210 	struct rproc_subdev *subdev;
1211 	int ret;
1212 
1213 	list_for_each_entry(subdev, &rproc->subdevs, node) {
1214 		if (subdev->start) {
1215 			ret = subdev->start(subdev);
1216 			if (ret)
1217 				goto unroll_registration;
1218 		}
1219 	}
1220 
1221 	return 0;
1222 
1223 unroll_registration:
1224 	list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node) {
1225 		if (subdev->stop)
1226 			subdev->stop(subdev, true);
1227 	}
1228 
1229 	return ret;
1230 }
1231 
1232 static void rproc_stop_subdevices(struct rproc *rproc, bool crashed)
1233 {
1234 	struct rproc_subdev *subdev;
1235 
1236 	list_for_each_entry_reverse(subdev, &rproc->subdevs, node) {
1237 		if (subdev->stop)
1238 			subdev->stop(subdev, crashed);
1239 	}
1240 }
1241 
1242 static void rproc_unprepare_subdevices(struct rproc *rproc)
1243 {
1244 	struct rproc_subdev *subdev;
1245 
1246 	list_for_each_entry_reverse(subdev, &rproc->subdevs, node) {
1247 		if (subdev->unprepare)
1248 			subdev->unprepare(subdev);
1249 	}
1250 }
1251 
1252 /**
1253  * rproc_alloc_registered_carveouts() - allocate all carveouts registered
1254  * in the list
1255  * @rproc: the remote processor handle
1256  *
1257  * This function parses registered carveout list, performs allocation
1258  * if alloc() ops registered and updates resource table information
1259  * if rsc_offset set.
1260  *
1261  * Return: 0 on success
1262  */
1263 static int rproc_alloc_registered_carveouts(struct rproc *rproc)
1264 {
1265 	struct rproc_mem_entry *entry, *tmp;
1266 	struct fw_rsc_carveout *rsc;
1267 	struct device *dev = &rproc->dev;
1268 	u64 pa;
1269 	int ret;
1270 
1271 	list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
1272 		if (entry->alloc) {
1273 			ret = entry->alloc(rproc, entry);
1274 			if (ret) {
1275 				dev_err(dev, "Unable to allocate carveout %s: %d\n",
1276 					entry->name, ret);
1277 				return -ENOMEM;
1278 			}
1279 		}
1280 
1281 		if (entry->rsc_offset != FW_RSC_ADDR_ANY) {
1282 			/* update resource table */
1283 			rsc = (void *)rproc->table_ptr + entry->rsc_offset;
1284 
1285 			/*
1286 			 * Some remote processors might need to know the pa
1287 			 * even though they are behind an IOMMU. E.g., OMAP4's
1288 			 * remote M3 processor needs this so it can control
1289 			 * on-chip hardware accelerators that are not behind
1290 			 * the IOMMU, and therefor must know the pa.
1291 			 *
1292 			 * Generally we don't want to expose physical addresses
1293 			 * if we don't have to (remote processors are generally
1294 			 * _not_ trusted), so we might want to do this only for
1295 			 * remote processor that _must_ have this (e.g. OMAP4's
1296 			 * dual M3 subsystem).
1297 			 *
1298 			 * Non-IOMMU processors might also want to have this info.
1299 			 * In this case, the device address and the physical address
1300 			 * are the same.
1301 			 */
1302 
1303 			/* Use va if defined else dma to generate pa */
1304 			if (entry->va)
1305 				pa = (u64)rproc_va_to_pa(entry->va);
1306 			else
1307 				pa = (u64)entry->dma;
1308 
1309 			if (((u64)pa) & HIGH_BITS_MASK)
1310 				dev_warn(dev,
1311 					 "Physical address cast in 32bit to fit resource table format\n");
1312 
1313 			rsc->pa = (u32)pa;
1314 			rsc->da = entry->da;
1315 			rsc->len = entry->len;
1316 		}
1317 	}
1318 
1319 	return 0;
1320 }
1321 
1322 
1323 /**
1324  * rproc_resource_cleanup() - clean up and free all acquired resources
1325  * @rproc: rproc handle
1326  *
1327  * This function will free all resources acquired for @rproc, and it
1328  * is called whenever @rproc either shuts down or fails to boot.
1329  */
1330 void rproc_resource_cleanup(struct rproc *rproc)
1331 {
1332 	struct rproc_mem_entry *entry, *tmp;
1333 	struct rproc_debug_trace *trace, *ttmp;
1334 	struct rproc_vdev *rvdev, *rvtmp;
1335 	struct device *dev = &rproc->dev;
1336 
1337 	/* clean up debugfs trace entries */
1338 	list_for_each_entry_safe(trace, ttmp, &rproc->traces, node) {
1339 		rproc_remove_trace_file(trace->tfile);
1340 		rproc->num_traces--;
1341 		list_del(&trace->node);
1342 		kfree(trace);
1343 	}
1344 
1345 	/* clean up iommu mapping entries */
1346 	list_for_each_entry_safe(entry, tmp, &rproc->mappings, node) {
1347 		size_t unmapped;
1348 
1349 		unmapped = iommu_unmap(rproc->domain, entry->da, entry->len);
1350 		if (unmapped != entry->len) {
1351 			/* nothing much to do besides complaining */
1352 			dev_err(dev, "failed to unmap %zx/%zu\n", entry->len,
1353 				unmapped);
1354 		}
1355 
1356 		list_del(&entry->node);
1357 		kfree(entry);
1358 	}
1359 
1360 	/* clean up carveout allocations */
1361 	list_for_each_entry_safe(entry, tmp, &rproc->carveouts, node) {
1362 		if (entry->release)
1363 			entry->release(rproc, entry);
1364 		list_del(&entry->node);
1365 		kfree(entry);
1366 	}
1367 
1368 	/* clean up remote vdev entries */
1369 	list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
1370 		kref_put(&rvdev->refcount, rproc_vdev_release);
1371 
1372 	rproc_coredump_cleanup(rproc);
1373 }
1374 EXPORT_SYMBOL(rproc_resource_cleanup);
1375 
1376 static int rproc_start(struct rproc *rproc, const struct firmware *fw)
1377 {
1378 	struct resource_table *loaded_table;
1379 	struct device *dev = &rproc->dev;
1380 	int ret;
1381 
1382 	/* load the ELF segments to memory */
1383 	ret = rproc_load_segments(rproc, fw);
1384 	if (ret) {
1385 		dev_err(dev, "Failed to load program segments: %d\n", ret);
1386 		return ret;
1387 	}
1388 
1389 	/*
1390 	 * The starting device has been given the rproc->cached_table as the
1391 	 * resource table. The address of the vring along with the other
1392 	 * allocated resources (carveouts etc) is stored in cached_table.
1393 	 * In order to pass this information to the remote device we must copy
1394 	 * this information to device memory. We also update the table_ptr so
1395 	 * that any subsequent changes will be applied to the loaded version.
1396 	 */
1397 	loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
1398 	if (loaded_table) {
1399 		memcpy(loaded_table, rproc->cached_table, rproc->table_sz);
1400 		rproc->table_ptr = loaded_table;
1401 	}
1402 
1403 	ret = rproc_prepare_subdevices(rproc);
1404 	if (ret) {
1405 		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
1406 			rproc->name, ret);
1407 		goto reset_table_ptr;
1408 	}
1409 
1410 	/* power up the remote processor */
1411 	ret = rproc->ops->start(rproc);
1412 	if (ret) {
1413 		dev_err(dev, "can't start rproc %s: %d\n", rproc->name, ret);
1414 		goto unprepare_subdevices;
1415 	}
1416 
1417 	/* Start any subdevices for the remote processor */
1418 	ret = rproc_start_subdevices(rproc);
1419 	if (ret) {
1420 		dev_err(dev, "failed to probe subdevices for %s: %d\n",
1421 			rproc->name, ret);
1422 		goto stop_rproc;
1423 	}
1424 
1425 	rproc->state = RPROC_RUNNING;
1426 
1427 	dev_info(dev, "remote processor %s is now up\n", rproc->name);
1428 
1429 	return 0;
1430 
1431 stop_rproc:
1432 	rproc->ops->stop(rproc);
1433 unprepare_subdevices:
1434 	rproc_unprepare_subdevices(rproc);
1435 reset_table_ptr:
1436 	rproc->table_ptr = rproc->cached_table;
1437 
1438 	return ret;
1439 }
1440 
1441 static int __rproc_attach(struct rproc *rproc)
1442 {
1443 	struct device *dev = &rproc->dev;
1444 	int ret;
1445 
1446 	ret = rproc_prepare_subdevices(rproc);
1447 	if (ret) {
1448 		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
1449 			rproc->name, ret);
1450 		goto out;
1451 	}
1452 
1453 	/* Attach to the remote processor */
1454 	ret = rproc_attach_device(rproc);
1455 	if (ret) {
1456 		dev_err(dev, "can't attach to rproc %s: %d\n",
1457 			rproc->name, ret);
1458 		goto unprepare_subdevices;
1459 	}
1460 
1461 	/* Start any subdevices for the remote processor */
1462 	ret = rproc_start_subdevices(rproc);
1463 	if (ret) {
1464 		dev_err(dev, "failed to probe subdevices for %s: %d\n",
1465 			rproc->name, ret);
1466 		goto stop_rproc;
1467 	}
1468 
1469 	rproc->state = RPROC_ATTACHED;
1470 
1471 	dev_info(dev, "remote processor %s is now attached\n", rproc->name);
1472 
1473 	return 0;
1474 
1475 stop_rproc:
1476 	rproc->ops->stop(rproc);
1477 unprepare_subdevices:
1478 	rproc_unprepare_subdevices(rproc);
1479 out:
1480 	return ret;
1481 }
1482 
1483 /*
1484  * take a firmware and boot a remote processor with it.
1485  */
1486 static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
1487 {
1488 	struct device *dev = &rproc->dev;
1489 	const char *name = rproc->firmware;
1490 	int ret;
1491 
1492 	ret = rproc_fw_sanity_check(rproc, fw);
1493 	if (ret)
1494 		return ret;
1495 
1496 	dev_info(dev, "Booting fw image %s, size %zd\n", name, fw->size);
1497 
1498 	/*
1499 	 * if enabling an IOMMU isn't relevant for this rproc, this is
1500 	 * just a nop
1501 	 */
1502 	ret = rproc_enable_iommu(rproc);
1503 	if (ret) {
1504 		dev_err(dev, "can't enable iommu: %d\n", ret);
1505 		return ret;
1506 	}
1507 
1508 	/* Prepare rproc for firmware loading if needed */
1509 	ret = rproc_prepare_device(rproc);
1510 	if (ret) {
1511 		dev_err(dev, "can't prepare rproc %s: %d\n", rproc->name, ret);
1512 		goto disable_iommu;
1513 	}
1514 
1515 	rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
1516 
1517 	/* Load resource table, core dump segment list etc from the firmware */
1518 	ret = rproc_parse_fw(rproc, fw);
1519 	if (ret)
1520 		goto unprepare_rproc;
1521 
1522 	/* reset max_notifyid */
1523 	rproc->max_notifyid = -1;
1524 
1525 	/* reset handled vdev */
1526 	rproc->nb_vdev = 0;
1527 
1528 	/* handle fw resources which are required to boot rproc */
1529 	ret = rproc_handle_resources(rproc, rproc_loading_handlers);
1530 	if (ret) {
1531 		dev_err(dev, "Failed to process resources: %d\n", ret);
1532 		goto clean_up_resources;
1533 	}
1534 
1535 	/* Allocate carveout resources associated to rproc */
1536 	ret = rproc_alloc_registered_carveouts(rproc);
1537 	if (ret) {
1538 		dev_err(dev, "Failed to allocate associated carveouts: %d\n",
1539 			ret);
1540 		goto clean_up_resources;
1541 	}
1542 
1543 	ret = rproc_start(rproc, fw);
1544 	if (ret)
1545 		goto clean_up_resources;
1546 
1547 	return 0;
1548 
1549 clean_up_resources:
1550 	rproc_resource_cleanup(rproc);
1551 	kfree(rproc->cached_table);
1552 	rproc->cached_table = NULL;
1553 	rproc->table_ptr = NULL;
1554 unprepare_rproc:
1555 	/* release HW resources if needed */
1556 	rproc_unprepare_device(rproc);
1557 disable_iommu:
1558 	rproc_disable_iommu(rproc);
1559 	return ret;
1560 }
1561 
1562 static int rproc_set_rsc_table(struct rproc *rproc)
1563 {
1564 	struct resource_table *table_ptr;
1565 	struct device *dev = &rproc->dev;
1566 	size_t table_sz;
1567 	int ret;
1568 
1569 	table_ptr = rproc_get_loaded_rsc_table(rproc, &table_sz);
1570 	if (!table_ptr) {
1571 		/* Not having a resource table is acceptable */
1572 		return 0;
1573 	}
1574 
1575 	if (IS_ERR(table_ptr)) {
1576 		ret = PTR_ERR(table_ptr);
1577 		dev_err(dev, "can't load resource table: %d\n", ret);
1578 		return ret;
1579 	}
1580 
1581 	/*
1582 	 * If it is possible to detach the remote processor, keep an untouched
1583 	 * copy of the resource table.  That way we can start fresh again when
1584 	 * the remote processor is re-attached, that is:
1585 	 *
1586 	 *      DETACHED -> ATTACHED -> DETACHED -> ATTACHED
1587 	 *
1588 	 * Free'd in rproc_reset_rsc_table_on_detach() and
1589 	 * rproc_reset_rsc_table_on_stop().
1590 	 */
1591 	if (rproc->ops->detach) {
1592 		rproc->clean_table = kmemdup(table_ptr, table_sz, GFP_KERNEL);
1593 		if (!rproc->clean_table)
1594 			return -ENOMEM;
1595 	} else {
1596 		rproc->clean_table = NULL;
1597 	}
1598 
1599 	rproc->cached_table = NULL;
1600 	rproc->table_ptr = table_ptr;
1601 	rproc->table_sz = table_sz;
1602 
1603 	return 0;
1604 }
1605 
1606 static int rproc_reset_rsc_table_on_detach(struct rproc *rproc)
1607 {
1608 	struct resource_table *table_ptr;
1609 
1610 	/* A resource table was never retrieved, nothing to do here */
1611 	if (!rproc->table_ptr)
1612 		return 0;
1613 
1614 	/*
1615 	 * If we made it to this point a clean_table _must_ have been
1616 	 * allocated in rproc_set_rsc_table().  If one isn't present
1617 	 * something went really wrong and we must complain.
1618 	 */
1619 	if (WARN_ON(!rproc->clean_table))
1620 		return -EINVAL;
1621 
1622 	/* Remember where the external entity installed the resource table */
1623 	table_ptr = rproc->table_ptr;
1624 
1625 	/*
1626 	 * If we made it here the remote processor was started by another
1627 	 * entity and a cache table doesn't exist.  As such make a copy of
1628 	 * the resource table currently used by the remote processor and
1629 	 * use that for the rest of the shutdown process.  The memory
1630 	 * allocated here is free'd in rproc_detach().
1631 	 */
1632 	rproc->cached_table = kmemdup(rproc->table_ptr,
1633 				      rproc->table_sz, GFP_KERNEL);
1634 	if (!rproc->cached_table)
1635 		return -ENOMEM;
1636 
1637 	/*
1638 	 * Use a copy of the resource table for the remainder of the
1639 	 * shutdown process.
1640 	 */
1641 	rproc->table_ptr = rproc->cached_table;
1642 
1643 	/*
1644 	 * Reset the memory area where the firmware loaded the resource table
1645 	 * to its original value.  That way when we re-attach the remote
1646 	 * processor the resource table is clean and ready to be used again.
1647 	 */
1648 	memcpy(table_ptr, rproc->clean_table, rproc->table_sz);
1649 
1650 	/*
1651 	 * The clean resource table is no longer needed.  Allocated in
1652 	 * rproc_set_rsc_table().
1653 	 */
1654 	kfree(rproc->clean_table);
1655 
1656 	return 0;
1657 }
1658 
1659 static int rproc_reset_rsc_table_on_stop(struct rproc *rproc)
1660 {
1661 	/* A resource table was never retrieved, nothing to do here */
1662 	if (!rproc->table_ptr)
1663 		return 0;
1664 
1665 	/*
1666 	 * If a cache table exists the remote processor was started by
1667 	 * the remoteproc core.  That cache table should be used for
1668 	 * the rest of the shutdown process.
1669 	 */
1670 	if (rproc->cached_table)
1671 		goto out;
1672 
1673 	/*
1674 	 * If we made it here the remote processor was started by another
1675 	 * entity and a cache table doesn't exist.  As such make a copy of
1676 	 * the resource table currently used by the remote processor and
1677 	 * use that for the rest of the shutdown process.  The memory
1678 	 * allocated here is free'd in rproc_shutdown().
1679 	 */
1680 	rproc->cached_table = kmemdup(rproc->table_ptr,
1681 				      rproc->table_sz, GFP_KERNEL);
1682 	if (!rproc->cached_table)
1683 		return -ENOMEM;
1684 
1685 	/*
1686 	 * Since the remote processor is being switched off the clean table
1687 	 * won't be needed.  Allocated in rproc_set_rsc_table().
1688 	 */
1689 	kfree(rproc->clean_table);
1690 
1691 out:
1692 	/*
1693 	 * Use a copy of the resource table for the remainder of the
1694 	 * shutdown process.
1695 	 */
1696 	rproc->table_ptr = rproc->cached_table;
1697 	return 0;
1698 }
1699 
1700 /*
1701  * Attach to remote processor - similar to rproc_fw_boot() but without
1702  * the steps that deal with the firmware image.
1703  */
1704 static int rproc_attach(struct rproc *rproc)
1705 {
1706 	struct device *dev = &rproc->dev;
1707 	int ret;
1708 
1709 	/*
1710 	 * if enabling an IOMMU isn't relevant for this rproc, this is
1711 	 * just a nop
1712 	 */
1713 	ret = rproc_enable_iommu(rproc);
1714 	if (ret) {
1715 		dev_err(dev, "can't enable iommu: %d\n", ret);
1716 		return ret;
1717 	}
1718 
1719 	/* Do anything that is needed to boot the remote processor */
1720 	ret = rproc_prepare_device(rproc);
1721 	if (ret) {
1722 		dev_err(dev, "can't prepare rproc %s: %d\n", rproc->name, ret);
1723 		goto disable_iommu;
1724 	}
1725 
1726 	ret = rproc_set_rsc_table(rproc);
1727 	if (ret) {
1728 		dev_err(dev, "can't load resource table: %d\n", ret);
1729 		goto unprepare_device;
1730 	}
1731 
1732 	/* reset max_notifyid */
1733 	rproc->max_notifyid = -1;
1734 
1735 	/* reset handled vdev */
1736 	rproc->nb_vdev = 0;
1737 
1738 	/*
1739 	 * Handle firmware resources required to attach to a remote processor.
1740 	 * Because we are attaching rather than booting the remote processor,
1741 	 * we expect the platform driver to properly set rproc->table_ptr.
1742 	 */
1743 	ret = rproc_handle_resources(rproc, rproc_loading_handlers);
1744 	if (ret) {
1745 		dev_err(dev, "Failed to process resources: %d\n", ret);
1746 		goto unprepare_device;
1747 	}
1748 
1749 	/* Allocate carveout resources associated to rproc */
1750 	ret = rproc_alloc_registered_carveouts(rproc);
1751 	if (ret) {
1752 		dev_err(dev, "Failed to allocate associated carveouts: %d\n",
1753 			ret);
1754 		goto clean_up_resources;
1755 	}
1756 
1757 	ret = __rproc_attach(rproc);
1758 	if (ret)
1759 		goto clean_up_resources;
1760 
1761 	return 0;
1762 
1763 clean_up_resources:
1764 	rproc_resource_cleanup(rproc);
1765 unprepare_device:
1766 	/* release HW resources if needed */
1767 	rproc_unprepare_device(rproc);
1768 disable_iommu:
1769 	rproc_disable_iommu(rproc);
1770 	return ret;
1771 }
1772 
1773 /*
1774  * take a firmware and boot it up.
1775  *
1776  * Note: this function is called asynchronously upon registration of the
1777  * remote processor (so we must wait until it completes before we try
1778  * to unregister the device. one other option is just to use kref here,
1779  * that might be cleaner).
1780  */
1781 static void rproc_auto_boot_callback(const struct firmware *fw, void *context)
1782 {
1783 	struct rproc *rproc = context;
1784 
1785 	rproc_boot(rproc);
1786 
1787 	release_firmware(fw);
1788 }
1789 
1790 static int rproc_trigger_auto_boot(struct rproc *rproc)
1791 {
1792 	int ret;
1793 
1794 	/*
1795 	 * Since the remote processor is in a detached state, it has already
1796 	 * been booted by another entity.  As such there is no point in waiting
1797 	 * for a firmware image to be loaded, we can simply initiate the process
1798 	 * of attaching to it immediately.
1799 	 */
1800 	if (rproc->state == RPROC_DETACHED)
1801 		return rproc_boot(rproc);
1802 
1803 	/*
1804 	 * We're initiating an asynchronous firmware loading, so we can
1805 	 * be built-in kernel code, without hanging the boot process.
1806 	 */
1807 	ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT,
1808 				      rproc->firmware, &rproc->dev, GFP_KERNEL,
1809 				      rproc, rproc_auto_boot_callback);
1810 	if (ret < 0)
1811 		dev_err(&rproc->dev, "request_firmware_nowait err: %d\n", ret);
1812 
1813 	return ret;
1814 }
1815 
1816 static int rproc_stop(struct rproc *rproc, bool crashed)
1817 {
1818 	struct device *dev = &rproc->dev;
1819 	int ret;
1820 
1821 	/* No need to continue if a stop() operation has not been provided */
1822 	if (!rproc->ops->stop)
1823 		return -EINVAL;
1824 
1825 	/* Stop any subdevices for the remote processor */
1826 	rproc_stop_subdevices(rproc, crashed);
1827 
1828 	/* the installed resource table is no longer accessible */
1829 	ret = rproc_reset_rsc_table_on_stop(rproc);
1830 	if (ret) {
1831 		dev_err(dev, "can't reset resource table: %d\n", ret);
1832 		return ret;
1833 	}
1834 
1835 
1836 	/* power off the remote processor */
1837 	ret = rproc->ops->stop(rproc);
1838 	if (ret) {
1839 		dev_err(dev, "can't stop rproc: %d\n", ret);
1840 		return ret;
1841 	}
1842 
1843 	rproc_unprepare_subdevices(rproc);
1844 
1845 	rproc->state = RPROC_OFFLINE;
1846 
1847 	dev_info(dev, "stopped remote processor %s\n", rproc->name);
1848 
1849 	return 0;
1850 }
1851 
1852 /*
1853  * __rproc_detach(): Does the opposite of __rproc_attach()
1854  */
1855 static int __rproc_detach(struct rproc *rproc)
1856 {
1857 	struct device *dev = &rproc->dev;
1858 	int ret;
1859 
1860 	/* No need to continue if a detach() operation has not been provided */
1861 	if (!rproc->ops->detach)
1862 		return -EINVAL;
1863 
1864 	/* Stop any subdevices for the remote processor */
1865 	rproc_stop_subdevices(rproc, false);
1866 
1867 	/* the installed resource table is no longer accessible */
1868 	ret = rproc_reset_rsc_table_on_detach(rproc);
1869 	if (ret) {
1870 		dev_err(dev, "can't reset resource table: %d\n", ret);
1871 		return ret;
1872 	}
1873 
1874 	/* Tell the remote processor the core isn't available anymore */
1875 	ret = rproc->ops->detach(rproc);
1876 	if (ret) {
1877 		dev_err(dev, "can't detach from rproc: %d\n", ret);
1878 		return ret;
1879 	}
1880 
1881 	rproc_unprepare_subdevices(rproc);
1882 
1883 	rproc->state = RPROC_DETACHED;
1884 
1885 	dev_info(dev, "detached remote processor %s\n", rproc->name);
1886 
1887 	return 0;
1888 }
1889 
1890 /**
1891  * rproc_trigger_recovery() - recover a remoteproc
1892  * @rproc: the remote processor
1893  *
1894  * The recovery is done by resetting all the virtio devices, that way all the
1895  * rpmsg drivers will be reseted along with the remote processor making the
1896  * remoteproc functional again.
1897  *
1898  * This function can sleep, so it cannot be called from atomic context.
1899  *
1900  * Return: 0 on success or a negative value upon failure
1901  */
1902 int rproc_trigger_recovery(struct rproc *rproc)
1903 {
1904 	const struct firmware *firmware_p;
1905 	struct device *dev = &rproc->dev;
1906 	int ret;
1907 
1908 	ret = mutex_lock_interruptible(&rproc->lock);
1909 	if (ret)
1910 		return ret;
1911 
1912 	/* State could have changed before we got the mutex */
1913 	if (rproc->state != RPROC_CRASHED)
1914 		goto unlock_mutex;
1915 
1916 	dev_err(dev, "recovering %s\n", rproc->name);
1917 
1918 	ret = rproc_stop(rproc, true);
1919 	if (ret)
1920 		goto unlock_mutex;
1921 
1922 	/* generate coredump */
1923 	rproc->ops->coredump(rproc);
1924 
1925 	/* load firmware */
1926 	ret = request_firmware(&firmware_p, rproc->firmware, dev);
1927 	if (ret < 0) {
1928 		dev_err(dev, "request_firmware failed: %d\n", ret);
1929 		goto unlock_mutex;
1930 	}
1931 
1932 	/* boot the remote processor up again */
1933 	ret = rproc_start(rproc, firmware_p);
1934 
1935 	release_firmware(firmware_p);
1936 
1937 unlock_mutex:
1938 	mutex_unlock(&rproc->lock);
1939 	return ret;
1940 }
1941 
1942 /**
1943  * rproc_crash_handler_work() - handle a crash
1944  * @work: work treating the crash
1945  *
1946  * This function needs to handle everything related to a crash, like cpu
1947  * registers and stack dump, information to help to debug the fatal error, etc.
1948  */
1949 static void rproc_crash_handler_work(struct work_struct *work)
1950 {
1951 	struct rproc *rproc = container_of(work, struct rproc, crash_handler);
1952 	struct device *dev = &rproc->dev;
1953 
1954 	dev_dbg(dev, "enter %s\n", __func__);
1955 
1956 	mutex_lock(&rproc->lock);
1957 
1958 	if (rproc->state == RPROC_CRASHED || rproc->state == RPROC_OFFLINE) {
1959 		/* handle only the first crash detected */
1960 		mutex_unlock(&rproc->lock);
1961 		return;
1962 	}
1963 
1964 	rproc->state = RPROC_CRASHED;
1965 	dev_err(dev, "handling crash #%u in %s\n", ++rproc->crash_cnt,
1966 		rproc->name);
1967 
1968 	mutex_unlock(&rproc->lock);
1969 
1970 	if (!rproc->recovery_disabled)
1971 		rproc_trigger_recovery(rproc);
1972 
1973 	pm_relax(rproc->dev.parent);
1974 }
1975 
1976 /**
1977  * rproc_boot() - boot a remote processor
1978  * @rproc: handle of a remote processor
1979  *
1980  * Boot a remote processor (i.e. load its firmware, power it on, ...).
1981  *
1982  * If the remote processor is already powered on, this function immediately
1983  * returns (successfully).
1984  *
1985  * Return: 0 on success, and an appropriate error value otherwise
1986  */
1987 int rproc_boot(struct rproc *rproc)
1988 {
1989 	const struct firmware *firmware_p;
1990 	struct device *dev;
1991 	int ret;
1992 
1993 	if (!rproc) {
1994 		pr_err("invalid rproc handle\n");
1995 		return -EINVAL;
1996 	}
1997 
1998 	dev = &rproc->dev;
1999 
2000 	ret = mutex_lock_interruptible(&rproc->lock);
2001 	if (ret) {
2002 		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
2003 		return ret;
2004 	}
2005 
2006 	if (rproc->state == RPROC_DELETED) {
2007 		ret = -ENODEV;
2008 		dev_err(dev, "can't boot deleted rproc %s\n", rproc->name);
2009 		goto unlock_mutex;
2010 	}
2011 
2012 	/* skip the boot or attach process if rproc is already powered up */
2013 	if (atomic_inc_return(&rproc->power) > 1) {
2014 		ret = 0;
2015 		goto unlock_mutex;
2016 	}
2017 
2018 	if (rproc->state == RPROC_DETACHED) {
2019 		dev_info(dev, "attaching to %s\n", rproc->name);
2020 
2021 		ret = rproc_attach(rproc);
2022 	} else {
2023 		dev_info(dev, "powering up %s\n", rproc->name);
2024 
2025 		/* load firmware */
2026 		ret = request_firmware(&firmware_p, rproc->firmware, dev);
2027 		if (ret < 0) {
2028 			dev_err(dev, "request_firmware failed: %d\n", ret);
2029 			goto downref_rproc;
2030 		}
2031 
2032 		ret = rproc_fw_boot(rproc, firmware_p);
2033 
2034 		release_firmware(firmware_p);
2035 	}
2036 
2037 downref_rproc:
2038 	if (ret)
2039 		atomic_dec(&rproc->power);
2040 unlock_mutex:
2041 	mutex_unlock(&rproc->lock);
2042 	return ret;
2043 }
2044 EXPORT_SYMBOL(rproc_boot);
2045 
2046 /**
2047  * rproc_shutdown() - power off the remote processor
2048  * @rproc: the remote processor
2049  *
2050  * Power off a remote processor (previously booted with rproc_boot()).
2051  *
2052  * In case @rproc is still being used by an additional user(s), then
2053  * this function will just decrement the power refcount and exit,
2054  * without really powering off the device.
2055  *
2056  * Every call to rproc_boot() must (eventually) be accompanied by a call
2057  * to rproc_shutdown(). Calling rproc_shutdown() redundantly is a bug.
2058  *
2059  * Notes:
2060  * - we're not decrementing the rproc's refcount, only the power refcount.
2061  *   which means that the @rproc handle stays valid even after rproc_shutdown()
2062  *   returns, and users can still use it with a subsequent rproc_boot(), if
2063  *   needed.
2064  *
2065  * Return: 0 on success, and an appropriate error value otherwise
2066  */
2067 int rproc_shutdown(struct rproc *rproc)
2068 {
2069 	struct device *dev = &rproc->dev;
2070 	int ret = 0;
2071 
2072 	ret = mutex_lock_interruptible(&rproc->lock);
2073 	if (ret) {
2074 		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
2075 		return ret;
2076 	}
2077 
2078 	/* if the remote proc is still needed, bail out */
2079 	if (!atomic_dec_and_test(&rproc->power))
2080 		goto out;
2081 
2082 	ret = rproc_stop(rproc, false);
2083 	if (ret) {
2084 		atomic_inc(&rproc->power);
2085 		goto out;
2086 	}
2087 
2088 	/* clean up all acquired resources */
2089 	rproc_resource_cleanup(rproc);
2090 
2091 	/* release HW resources if needed */
2092 	rproc_unprepare_device(rproc);
2093 
2094 	rproc_disable_iommu(rproc);
2095 
2096 	/* Free the copy of the resource table */
2097 	kfree(rproc->cached_table);
2098 	rproc->cached_table = NULL;
2099 	rproc->table_ptr = NULL;
2100 out:
2101 	mutex_unlock(&rproc->lock);
2102 	return ret;
2103 }
2104 EXPORT_SYMBOL(rproc_shutdown);
2105 
2106 /**
2107  * rproc_detach() - Detach the remote processor from the
2108  * remoteproc core
2109  *
2110  * @rproc: the remote processor
2111  *
2112  * Detach a remote processor (previously attached to with rproc_attach()).
2113  *
2114  * In case @rproc is still being used by an additional user(s), then
2115  * this function will just decrement the power refcount and exit,
2116  * without disconnecting the device.
2117  *
2118  * Function rproc_detach() calls __rproc_detach() in order to let a remote
2119  * processor know that services provided by the application processor are
2120  * no longer available.  From there it should be possible to remove the
2121  * platform driver and even power cycle the application processor (if the HW
2122  * supports it) without needing to switch off the remote processor.
2123  *
2124  * Return: 0 on success, and an appropriate error value otherwise
2125  */
2126 int rproc_detach(struct rproc *rproc)
2127 {
2128 	struct device *dev = &rproc->dev;
2129 	int ret;
2130 
2131 	ret = mutex_lock_interruptible(&rproc->lock);
2132 	if (ret) {
2133 		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
2134 		return ret;
2135 	}
2136 
2137 	/* if the remote proc is still needed, bail out */
2138 	if (!atomic_dec_and_test(&rproc->power)) {
2139 		ret = 0;
2140 		goto out;
2141 	}
2142 
2143 	ret = __rproc_detach(rproc);
2144 	if (ret) {
2145 		atomic_inc(&rproc->power);
2146 		goto out;
2147 	}
2148 
2149 	/* clean up all acquired resources */
2150 	rproc_resource_cleanup(rproc);
2151 
2152 	/* release HW resources if needed */
2153 	rproc_unprepare_device(rproc);
2154 
2155 	rproc_disable_iommu(rproc);
2156 
2157 	/* Free the copy of the resource table */
2158 	kfree(rproc->cached_table);
2159 	rproc->cached_table = NULL;
2160 	rproc->table_ptr = NULL;
2161 out:
2162 	mutex_unlock(&rproc->lock);
2163 	return ret;
2164 }
2165 EXPORT_SYMBOL(rproc_detach);
2166 
2167 /**
2168  * rproc_get_by_phandle() - find a remote processor by phandle
2169  * @phandle: phandle to the rproc
2170  *
2171  * Finds an rproc handle using the remote processor's phandle, and then
2172  * return a handle to the rproc.
2173  *
2174  * This function increments the remote processor's refcount, so always
2175  * use rproc_put() to decrement it back once rproc isn't needed anymore.
2176  *
2177  * Return: rproc handle on success, and NULL on failure
2178  */
2179 #ifdef CONFIG_OF
2180 struct rproc *rproc_get_by_phandle(phandle phandle)
2181 {
2182 	struct rproc *rproc = NULL, *r;
2183 	struct device_node *np;
2184 
2185 	np = of_find_node_by_phandle(phandle);
2186 	if (!np)
2187 		return NULL;
2188 
2189 	rcu_read_lock();
2190 	list_for_each_entry_rcu(r, &rproc_list, node) {
2191 		if (r->dev.parent && r->dev.parent->of_node == np) {
2192 			/* prevent underlying implementation from being removed */
2193 			if (!try_module_get(r->dev.parent->driver->owner)) {
2194 				dev_err(&r->dev, "can't get owner\n");
2195 				break;
2196 			}
2197 
2198 			rproc = r;
2199 			get_device(&rproc->dev);
2200 			break;
2201 		}
2202 	}
2203 	rcu_read_unlock();
2204 
2205 	of_node_put(np);
2206 
2207 	return rproc;
2208 }
2209 #else
2210 struct rproc *rproc_get_by_phandle(phandle phandle)
2211 {
2212 	return NULL;
2213 }
2214 #endif
2215 EXPORT_SYMBOL(rproc_get_by_phandle);
2216 
2217 /**
2218  * rproc_set_firmware() - assign a new firmware
2219  * @rproc: rproc handle to which the new firmware is being assigned
2220  * @fw_name: new firmware name to be assigned
2221  *
2222  * This function allows remoteproc drivers or clients to configure a custom
2223  * firmware name that is different from the default name used during remoteproc
2224  * registration. The function does not trigger a remote processor boot,
2225  * only sets the firmware name used for a subsequent boot. This function
2226  * should also be called only when the remote processor is offline.
2227  *
2228  * This allows either the userspace to configure a different name through
2229  * sysfs or a kernel-level remoteproc or a remoteproc client driver to set
2230  * a specific firmware when it is controlling the boot and shutdown of the
2231  * remote processor.
2232  *
2233  * Return: 0 on success or a negative value upon failure
2234  */
2235 int rproc_set_firmware(struct rproc *rproc, const char *fw_name)
2236 {
2237 	struct device *dev;
2238 	int ret, len;
2239 	char *p;
2240 
2241 	if (!rproc || !fw_name)
2242 		return -EINVAL;
2243 
2244 	dev = rproc->dev.parent;
2245 
2246 	ret = mutex_lock_interruptible(&rproc->lock);
2247 	if (ret) {
2248 		dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret);
2249 		return -EINVAL;
2250 	}
2251 
2252 	if (rproc->state != RPROC_OFFLINE) {
2253 		dev_err(dev, "can't change firmware while running\n");
2254 		ret = -EBUSY;
2255 		goto out;
2256 	}
2257 
2258 	len = strcspn(fw_name, "\n");
2259 	if (!len) {
2260 		dev_err(dev, "can't provide empty string for firmware name\n");
2261 		ret = -EINVAL;
2262 		goto out;
2263 	}
2264 
2265 	p = kstrndup(fw_name, len, GFP_KERNEL);
2266 	if (!p) {
2267 		ret = -ENOMEM;
2268 		goto out;
2269 	}
2270 
2271 	kfree_const(rproc->firmware);
2272 	rproc->firmware = p;
2273 
2274 out:
2275 	mutex_unlock(&rproc->lock);
2276 	return ret;
2277 }
2278 EXPORT_SYMBOL(rproc_set_firmware);
2279 
2280 static int rproc_validate(struct rproc *rproc)
2281 {
2282 	switch (rproc->state) {
2283 	case RPROC_OFFLINE:
2284 		/*
2285 		 * An offline processor without a start()
2286 		 * function makes no sense.
2287 		 */
2288 		if (!rproc->ops->start)
2289 			return -EINVAL;
2290 		break;
2291 	case RPROC_DETACHED:
2292 		/*
2293 		 * A remote processor in a detached state without an
2294 		 * attach() function makes not sense.
2295 		 */
2296 		if (!rproc->ops->attach)
2297 			return -EINVAL;
2298 		/*
2299 		 * When attaching to a remote processor the device memory
2300 		 * is already available and as such there is no need to have a
2301 		 * cached table.
2302 		 */
2303 		if (rproc->cached_table)
2304 			return -EINVAL;
2305 		break;
2306 	default:
2307 		/*
2308 		 * When adding a remote processor, the state of the device
2309 		 * can be offline or detached, nothing else.
2310 		 */
2311 		return -EINVAL;
2312 	}
2313 
2314 	return 0;
2315 }
2316 
2317 /**
2318  * rproc_add() - register a remote processor
2319  * @rproc: the remote processor handle to register
2320  *
2321  * Registers @rproc with the remoteproc framework, after it has been
2322  * allocated with rproc_alloc().
2323  *
2324  * This is called by the platform-specific rproc implementation, whenever
2325  * a new remote processor device is probed.
2326  *
2327  * Note: this function initiates an asynchronous firmware loading
2328  * context, which will look for virtio devices supported by the rproc's
2329  * firmware.
2330  *
2331  * If found, those virtio devices will be created and added, so as a result
2332  * of registering this remote processor, additional virtio drivers might be
2333  * probed.
2334  *
2335  * Return: 0 on success and an appropriate error code otherwise
2336  */
2337 int rproc_add(struct rproc *rproc)
2338 {
2339 	struct device *dev = &rproc->dev;
2340 	int ret;
2341 
2342 	ret = rproc_validate(rproc);
2343 	if (ret < 0)
2344 		return ret;
2345 
2346 	/* add char device for this remoteproc */
2347 	ret = rproc_char_device_add(rproc);
2348 	if (ret < 0)
2349 		return ret;
2350 
2351 	ret = device_add(dev);
2352 	if (ret < 0) {
2353 		put_device(dev);
2354 		goto rproc_remove_cdev;
2355 	}
2356 
2357 	dev_info(dev, "%s is available\n", rproc->name);
2358 
2359 	/* create debugfs entries */
2360 	rproc_create_debug_dir(rproc);
2361 
2362 	/* if rproc is marked always-on, request it to boot */
2363 	if (rproc->auto_boot) {
2364 		ret = rproc_trigger_auto_boot(rproc);
2365 		if (ret < 0)
2366 			goto rproc_remove_dev;
2367 	}
2368 
2369 	/* expose to rproc_get_by_phandle users */
2370 	mutex_lock(&rproc_list_mutex);
2371 	list_add_rcu(&rproc->node, &rproc_list);
2372 	mutex_unlock(&rproc_list_mutex);
2373 
2374 	return 0;
2375 
2376 rproc_remove_dev:
2377 	rproc_delete_debug_dir(rproc);
2378 	device_del(dev);
2379 rproc_remove_cdev:
2380 	rproc_char_device_remove(rproc);
2381 	return ret;
2382 }
2383 EXPORT_SYMBOL(rproc_add);
2384 
2385 static void devm_rproc_remove(void *rproc)
2386 {
2387 	rproc_del(rproc);
2388 }
2389 
2390 /**
2391  * devm_rproc_add() - resource managed rproc_add()
2392  * @dev: the underlying device
2393  * @rproc: the remote processor handle to register
2394  *
2395  * This function performs like rproc_add() but the registered rproc device will
2396  * automatically be removed on driver detach.
2397  *
2398  * Return: 0 on success, negative errno on failure
2399  */
2400 int devm_rproc_add(struct device *dev, struct rproc *rproc)
2401 {
2402 	int err;
2403 
2404 	err = rproc_add(rproc);
2405 	if (err)
2406 		return err;
2407 
2408 	return devm_add_action_or_reset(dev, devm_rproc_remove, rproc);
2409 }
2410 EXPORT_SYMBOL(devm_rproc_add);
2411 
2412 /**
2413  * rproc_type_release() - release a remote processor instance
2414  * @dev: the rproc's device
2415  *
2416  * This function should _never_ be called directly.
2417  *
2418  * It will be called by the driver core when no one holds a valid pointer
2419  * to @dev anymore.
2420  */
2421 static void rproc_type_release(struct device *dev)
2422 {
2423 	struct rproc *rproc = container_of(dev, struct rproc, dev);
2424 
2425 	dev_info(&rproc->dev, "releasing %s\n", rproc->name);
2426 
2427 	idr_destroy(&rproc->notifyids);
2428 
2429 	if (rproc->index >= 0)
2430 		ida_simple_remove(&rproc_dev_index, rproc->index);
2431 
2432 	kfree_const(rproc->firmware);
2433 	kfree_const(rproc->name);
2434 	kfree(rproc->ops);
2435 	kfree(rproc);
2436 }
2437 
2438 static const struct device_type rproc_type = {
2439 	.name		= "remoteproc",
2440 	.release	= rproc_type_release,
2441 };
2442 
2443 static int rproc_alloc_firmware(struct rproc *rproc,
2444 				const char *name, const char *firmware)
2445 {
2446 	const char *p;
2447 
2448 	/*
2449 	 * Allocate a firmware name if the caller gave us one to work
2450 	 * with.  Otherwise construct a new one using a default pattern.
2451 	 */
2452 	if (firmware)
2453 		p = kstrdup_const(firmware, GFP_KERNEL);
2454 	else
2455 		p = kasprintf(GFP_KERNEL, "rproc-%s-fw", name);
2456 
2457 	if (!p)
2458 		return -ENOMEM;
2459 
2460 	rproc->firmware = p;
2461 
2462 	return 0;
2463 }
2464 
2465 static int rproc_alloc_ops(struct rproc *rproc, const struct rproc_ops *ops)
2466 {
2467 	rproc->ops = kmemdup(ops, sizeof(*ops), GFP_KERNEL);
2468 	if (!rproc->ops)
2469 		return -ENOMEM;
2470 
2471 	/* Default to rproc_coredump if no coredump function is specified */
2472 	if (!rproc->ops->coredump)
2473 		rproc->ops->coredump = rproc_coredump;
2474 
2475 	if (rproc->ops->load)
2476 		return 0;
2477 
2478 	/* Default to ELF loader if no load function is specified */
2479 	rproc->ops->load = rproc_elf_load_segments;
2480 	rproc->ops->parse_fw = rproc_elf_load_rsc_table;
2481 	rproc->ops->find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table;
2482 	rproc->ops->sanity_check = rproc_elf_sanity_check;
2483 	rproc->ops->get_boot_addr = rproc_elf_get_boot_addr;
2484 
2485 	return 0;
2486 }
2487 
2488 /**
2489  * rproc_alloc() - allocate a remote processor handle
2490  * @dev: the underlying device
2491  * @name: name of this remote processor
2492  * @ops: platform-specific handlers (mainly start/stop)
2493  * @firmware: name of firmware file to load, can be NULL
2494  * @len: length of private data needed by the rproc driver (in bytes)
2495  *
2496  * Allocates a new remote processor handle, but does not register
2497  * it yet. if @firmware is NULL, a default name is used.
2498  *
2499  * This function should be used by rproc implementations during initialization
2500  * of the remote processor.
2501  *
2502  * After creating an rproc handle using this function, and when ready,
2503  * implementations should then call rproc_add() to complete
2504  * the registration of the remote processor.
2505  *
2506  * Note: _never_ directly deallocate @rproc, even if it was not registered
2507  * yet. Instead, when you need to unroll rproc_alloc(), use rproc_free().
2508  *
2509  * Return: new rproc pointer on success, and NULL on failure
2510  */
2511 struct rproc *rproc_alloc(struct device *dev, const char *name,
2512 			  const struct rproc_ops *ops,
2513 			  const char *firmware, int len)
2514 {
2515 	struct rproc *rproc;
2516 
2517 	if (!dev || !name || !ops)
2518 		return NULL;
2519 
2520 	rproc = kzalloc(sizeof(struct rproc) + len, GFP_KERNEL);
2521 	if (!rproc)
2522 		return NULL;
2523 
2524 	rproc->priv = &rproc[1];
2525 	rproc->auto_boot = true;
2526 	rproc->elf_class = ELFCLASSNONE;
2527 	rproc->elf_machine = EM_NONE;
2528 
2529 	device_initialize(&rproc->dev);
2530 	rproc->dev.parent = dev;
2531 	rproc->dev.type = &rproc_type;
2532 	rproc->dev.class = &rproc_class;
2533 	rproc->dev.driver_data = rproc;
2534 	idr_init(&rproc->notifyids);
2535 
2536 	rproc->name = kstrdup_const(name, GFP_KERNEL);
2537 	if (!rproc->name)
2538 		goto put_device;
2539 
2540 	if (rproc_alloc_firmware(rproc, name, firmware))
2541 		goto put_device;
2542 
2543 	if (rproc_alloc_ops(rproc, ops))
2544 		goto put_device;
2545 
2546 	/* Assign a unique device index and name */
2547 	rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL);
2548 	if (rproc->index < 0) {
2549 		dev_err(dev, "ida_simple_get failed: %d\n", rproc->index);
2550 		goto put_device;
2551 	}
2552 
2553 	dev_set_name(&rproc->dev, "remoteproc%d", rproc->index);
2554 
2555 	atomic_set(&rproc->power, 0);
2556 
2557 	mutex_init(&rproc->lock);
2558 
2559 	INIT_LIST_HEAD(&rproc->carveouts);
2560 	INIT_LIST_HEAD(&rproc->mappings);
2561 	INIT_LIST_HEAD(&rproc->traces);
2562 	INIT_LIST_HEAD(&rproc->rvdevs);
2563 	INIT_LIST_HEAD(&rproc->subdevs);
2564 	INIT_LIST_HEAD(&rproc->dump_segments);
2565 
2566 	INIT_WORK(&rproc->crash_handler, rproc_crash_handler_work);
2567 
2568 	rproc->state = RPROC_OFFLINE;
2569 
2570 	return rproc;
2571 
2572 put_device:
2573 	put_device(&rproc->dev);
2574 	return NULL;
2575 }
2576 EXPORT_SYMBOL(rproc_alloc);
2577 
2578 /**
2579  * rproc_free() - unroll rproc_alloc()
2580  * @rproc: the remote processor handle
2581  *
2582  * This function decrements the rproc dev refcount.
2583  *
2584  * If no one holds any reference to rproc anymore, then its refcount would
2585  * now drop to zero, and it would be freed.
2586  */
2587 void rproc_free(struct rproc *rproc)
2588 {
2589 	put_device(&rproc->dev);
2590 }
2591 EXPORT_SYMBOL(rproc_free);
2592 
2593 /**
2594  * rproc_put() - release rproc reference
2595  * @rproc: the remote processor handle
2596  *
2597  * This function decrements the rproc dev refcount.
2598  *
2599  * If no one holds any reference to rproc anymore, then its refcount would
2600  * now drop to zero, and it would be freed.
2601  */
2602 void rproc_put(struct rproc *rproc)
2603 {
2604 	module_put(rproc->dev.parent->driver->owner);
2605 	put_device(&rproc->dev);
2606 }
2607 EXPORT_SYMBOL(rproc_put);
2608 
2609 /**
2610  * rproc_del() - unregister a remote processor
2611  * @rproc: rproc handle to unregister
2612  *
2613  * This function should be called when the platform specific rproc
2614  * implementation decides to remove the rproc device. it should
2615  * _only_ be called if a previous invocation of rproc_add()
2616  * has completed successfully.
2617  *
2618  * After rproc_del() returns, @rproc isn't freed yet, because
2619  * of the outstanding reference created by rproc_alloc. To decrement that
2620  * one last refcount, one still needs to call rproc_free().
2621  *
2622  * Return: 0 on success and -EINVAL if @rproc isn't valid
2623  */
2624 int rproc_del(struct rproc *rproc)
2625 {
2626 	if (!rproc)
2627 		return -EINVAL;
2628 
2629 	/* TODO: make sure this works with rproc->power > 1 */
2630 	rproc_shutdown(rproc);
2631 
2632 	mutex_lock(&rproc->lock);
2633 	rproc->state = RPROC_DELETED;
2634 	mutex_unlock(&rproc->lock);
2635 
2636 	rproc_delete_debug_dir(rproc);
2637 
2638 	/* the rproc is downref'ed as soon as it's removed from the klist */
2639 	mutex_lock(&rproc_list_mutex);
2640 	list_del_rcu(&rproc->node);
2641 	mutex_unlock(&rproc_list_mutex);
2642 
2643 	/* Ensure that no readers of rproc_list are still active */
2644 	synchronize_rcu();
2645 
2646 	device_del(&rproc->dev);
2647 	rproc_char_device_remove(rproc);
2648 
2649 	return 0;
2650 }
2651 EXPORT_SYMBOL(rproc_del);
2652 
2653 static void devm_rproc_free(struct device *dev, void *res)
2654 {
2655 	rproc_free(*(struct rproc **)res);
2656 }
2657 
2658 /**
2659  * devm_rproc_alloc() - resource managed rproc_alloc()
2660  * @dev: the underlying device
2661  * @name: name of this remote processor
2662  * @ops: platform-specific handlers (mainly start/stop)
2663  * @firmware: name of firmware file to load, can be NULL
2664  * @len: length of private data needed by the rproc driver (in bytes)
2665  *
2666  * This function performs like rproc_alloc() but the acquired rproc device will
2667  * automatically be released on driver detach.
2668  *
2669  * Return: new rproc instance, or NULL on failure
2670  */
2671 struct rproc *devm_rproc_alloc(struct device *dev, const char *name,
2672 			       const struct rproc_ops *ops,
2673 			       const char *firmware, int len)
2674 {
2675 	struct rproc **ptr, *rproc;
2676 
2677 	ptr = devres_alloc(devm_rproc_free, sizeof(*ptr), GFP_KERNEL);
2678 	if (!ptr)
2679 		return NULL;
2680 
2681 	rproc = rproc_alloc(dev, name, ops, firmware, len);
2682 	if (rproc) {
2683 		*ptr = rproc;
2684 		devres_add(dev, ptr);
2685 	} else {
2686 		devres_free(ptr);
2687 	}
2688 
2689 	return rproc;
2690 }
2691 EXPORT_SYMBOL(devm_rproc_alloc);
2692 
2693 /**
2694  * rproc_add_subdev() - add a subdevice to a remoteproc
2695  * @rproc: rproc handle to add the subdevice to
2696  * @subdev: subdev handle to register
2697  *
2698  * Caller is responsible for populating optional subdevice function pointers.
2699  */
2700 void rproc_add_subdev(struct rproc *rproc, struct rproc_subdev *subdev)
2701 {
2702 	list_add_tail(&subdev->node, &rproc->subdevs);
2703 }
2704 EXPORT_SYMBOL(rproc_add_subdev);
2705 
2706 /**
2707  * rproc_remove_subdev() - remove a subdevice from a remoteproc
2708  * @rproc: rproc handle to remove the subdevice from
2709  * @subdev: subdev handle, previously registered with rproc_add_subdev()
2710  */
2711 void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev)
2712 {
2713 	list_del(&subdev->node);
2714 }
2715 EXPORT_SYMBOL(rproc_remove_subdev);
2716 
2717 /**
2718  * rproc_get_by_child() - acquire rproc handle of @dev's ancestor
2719  * @dev:	child device to find ancestor of
2720  *
2721  * Return: the ancestor rproc instance, or NULL if not found
2722  */
2723 struct rproc *rproc_get_by_child(struct device *dev)
2724 {
2725 	for (dev = dev->parent; dev; dev = dev->parent) {
2726 		if (dev->type == &rproc_type)
2727 			return dev->driver_data;
2728 	}
2729 
2730 	return NULL;
2731 }
2732 EXPORT_SYMBOL(rproc_get_by_child);
2733 
2734 /**
2735  * rproc_report_crash() - rproc crash reporter function
2736  * @rproc: remote processor
2737  * @type: crash type
2738  *
2739  * This function must be called every time a crash is detected by the low-level
2740  * drivers implementing a specific remoteproc. This should not be called from a
2741  * non-remoteproc driver.
2742  *
2743  * This function can be called from atomic/interrupt context.
2744  */
2745 void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type)
2746 {
2747 	if (!rproc) {
2748 		pr_err("NULL rproc pointer\n");
2749 		return;
2750 	}
2751 
2752 	/* Prevent suspend while the remoteproc is being recovered */
2753 	pm_stay_awake(rproc->dev.parent);
2754 
2755 	dev_err(&rproc->dev, "crash detected in %s: type %s\n",
2756 		rproc->name, rproc_crash_to_string(type));
2757 
2758 	/* Have a worker handle the error; ensure system is not suspended */
2759 	queue_work(system_freezable_wq, &rproc->crash_handler);
2760 }
2761 EXPORT_SYMBOL(rproc_report_crash);
2762 
2763 static int rproc_panic_handler(struct notifier_block *nb, unsigned long event,
2764 			       void *ptr)
2765 {
2766 	unsigned int longest = 0;
2767 	struct rproc *rproc;
2768 	unsigned int d;
2769 
2770 	rcu_read_lock();
2771 	list_for_each_entry_rcu(rproc, &rproc_list, node) {
2772 		if (!rproc->ops->panic)
2773 			continue;
2774 
2775 		if (rproc->state != RPROC_RUNNING &&
2776 		    rproc->state != RPROC_ATTACHED)
2777 			continue;
2778 
2779 		d = rproc->ops->panic(rproc);
2780 		longest = max(longest, d);
2781 	}
2782 	rcu_read_unlock();
2783 
2784 	/*
2785 	 * Delay for the longest requested duration before returning. This can
2786 	 * be used by the remoteproc drivers to give the remote processor time
2787 	 * to perform any requested operations (such as flush caches), when
2788 	 * it's not possible to signal the Linux side due to the panic.
2789 	 */
2790 	mdelay(longest);
2791 
2792 	return NOTIFY_DONE;
2793 }
2794 
2795 static void __init rproc_init_panic(void)
2796 {
2797 	rproc_panic_nb.notifier_call = rproc_panic_handler;
2798 	atomic_notifier_chain_register(&panic_notifier_list, &rproc_panic_nb);
2799 }
2800 
2801 static void __exit rproc_exit_panic(void)
2802 {
2803 	atomic_notifier_chain_unregister(&panic_notifier_list, &rproc_panic_nb);
2804 }
2805 
2806 static int __init remoteproc_init(void)
2807 {
2808 	rproc_init_sysfs();
2809 	rproc_init_debugfs();
2810 	rproc_init_cdev();
2811 	rproc_init_panic();
2812 
2813 	return 0;
2814 }
2815 subsys_initcall(remoteproc_init);
2816 
2817 static void __exit remoteproc_exit(void)
2818 {
2819 	ida_destroy(&rproc_dev_index);
2820 
2821 	rproc_exit_panic();
2822 	rproc_exit_debugfs();
2823 	rproc_exit_sysfs();
2824 }
2825 module_exit(remoteproc_exit);
2826 
2827 MODULE_LICENSE("GPL v2");
2828 MODULE_DESCRIPTION("Generic Remote Processor Framework");
2829