1// SPDX-License-Identifier: GPL-2.0
2/*
3 * fsl-mc object allocator driver
4 *
5 * Copyright (C) 2013-2016 Freescale Semiconductor, Inc.
6 *
7 */
8
9#include <linux/module.h>
10#include <linux/msi.h>
11#include <linux/fsl/mc.h>
12
13#include "fsl-mc-private.h"
14
15static bool __must_check fsl_mc_is_allocatable(struct fsl_mc_device *mc_dev)
16{
17	return is_fsl_mc_bus_dpbp(mc_dev) ||
18	       is_fsl_mc_bus_dpmcp(mc_dev) ||
19	       is_fsl_mc_bus_dpcon(mc_dev);
20}
21
22/**
23 * fsl_mc_resource_pool_add_device - add allocatable object to a resource
24 * pool of a given fsl-mc bus
25 *
26 * @mc_bus: pointer to the fsl-mc bus
27 * @pool_type: pool type
28 * @mc_dev: pointer to allocatable fsl-mc device
29 */
30static int __must_check fsl_mc_resource_pool_add_device(struct fsl_mc_bus
31								*mc_bus,
32							enum fsl_mc_pool_type
33								pool_type,
34							struct fsl_mc_device
35								*mc_dev)
36{
37	struct fsl_mc_resource_pool *res_pool;
38	struct fsl_mc_resource *resource;
39	struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
40	int error = -EINVAL;
41
42	if (pool_type < 0 || pool_type >= FSL_MC_NUM_POOL_TYPES)
43		goto out;
44	if (!fsl_mc_is_allocatable(mc_dev))
45		goto out;
46	if (mc_dev->resource)
47		goto out;
48
49	res_pool = &mc_bus->resource_pools[pool_type];
50	if (res_pool->type != pool_type)
51		goto out;
52	if (res_pool->mc_bus != mc_bus)
53		goto out;
54
55	mutex_lock(&res_pool->mutex);
56
57	if (res_pool->max_count < 0)
58		goto out_unlock;
59	if (res_pool->free_count < 0 ||
60	    res_pool->free_count > res_pool->max_count)
61		goto out_unlock;
62
63	resource = devm_kzalloc(&mc_bus_dev->dev, sizeof(*resource),
64				GFP_KERNEL);
65	if (!resource) {
66		error = -ENOMEM;
67		dev_err(&mc_bus_dev->dev,
68			"Failed to allocate memory for fsl_mc_resource\n");
69		goto out_unlock;
70	}
71
72	resource->type = pool_type;
73	resource->id = mc_dev->obj_desc.id;
74	resource->data = mc_dev;
75	resource->parent_pool = res_pool;
76	INIT_LIST_HEAD(&resource->node);
77	list_add_tail(&resource->node, &res_pool->free_list);
78	mc_dev->resource = resource;
79	res_pool->free_count++;
80	res_pool->max_count++;
81	error = 0;
82out_unlock:
83	mutex_unlock(&res_pool->mutex);
84out:
85	return error;
86}
87
88/**
89 * fsl_mc_resource_pool_remove_device - remove an allocatable device from a
90 * resource pool
91 *
92 * @mc_dev: pointer to allocatable fsl-mc device
93 *
94 * It permanently removes an allocatable fsl-mc device from the resource
95 * pool. It's an error if the device is in use.
96 */
97static int __must_check fsl_mc_resource_pool_remove_device(struct fsl_mc_device
98								   *mc_dev)
99{
100	struct fsl_mc_device *mc_bus_dev;
101	struct fsl_mc_bus *mc_bus;
102	struct fsl_mc_resource_pool *res_pool;
103	struct fsl_mc_resource *resource;
104	int error = -EINVAL;
105
106	if (!fsl_mc_is_allocatable(mc_dev))
107		goto out;
108
109	resource = mc_dev->resource;
110	if (!resource || resource->data != mc_dev)
111		goto out;
112
113	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
114	mc_bus = to_fsl_mc_bus(mc_bus_dev);
115	res_pool = resource->parent_pool;
116	if (res_pool != &mc_bus->resource_pools[resource->type])
117		goto out;
118
119	mutex_lock(&res_pool->mutex);
120
121	if (res_pool->max_count <= 0)
122		goto out_unlock;
123	if (res_pool->free_count <= 0 ||
124	    res_pool->free_count > res_pool->max_count)
125		goto out_unlock;
126
127	/*
128	 * If the device is currently allocated, its resource is not
129	 * in the free list and thus, the device cannot be removed.
130	 */
131	if (list_empty(&resource->node)) {
132		error = -EBUSY;
133		dev_err(&mc_bus_dev->dev,
134			"Device %s cannot be removed from resource pool\n",
135			dev_name(&mc_dev->dev));
136		goto out_unlock;
137	}
138
139	list_del_init(&resource->node);
140	res_pool->free_count--;
141	res_pool->max_count--;
142
143	devm_kfree(&mc_bus_dev->dev, resource);
144	mc_dev->resource = NULL;
145	error = 0;
146out_unlock:
147	mutex_unlock(&res_pool->mutex);
148out:
149	return error;
150}
151
152static const char *const fsl_mc_pool_type_strings[] = {
153	[FSL_MC_POOL_DPMCP] = "dpmcp",
154	[FSL_MC_POOL_DPBP] = "dpbp",
155	[FSL_MC_POOL_DPCON] = "dpcon",
156	[FSL_MC_POOL_IRQ] = "irq",
157};
158
159static int __must_check object_type_to_pool_type(const char *object_type,
160						 enum fsl_mc_pool_type
161								*pool_type)
162{
163	unsigned int i;
164
165	for (i = 0; i < ARRAY_SIZE(fsl_mc_pool_type_strings); i++) {
166		if (strcmp(object_type, fsl_mc_pool_type_strings[i]) == 0) {
167			*pool_type = i;
168			return 0;
169		}
170	}
171
172	return -EINVAL;
173}
174
175int __must_check fsl_mc_resource_allocate(struct fsl_mc_bus *mc_bus,
176					  enum fsl_mc_pool_type pool_type,
177					  struct fsl_mc_resource **new_resource)
178{
179	struct fsl_mc_resource_pool *res_pool;
180	struct fsl_mc_resource *resource;
181	struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
182	int error = -EINVAL;
183
184	BUILD_BUG_ON(ARRAY_SIZE(fsl_mc_pool_type_strings) !=
185		     FSL_MC_NUM_POOL_TYPES);
186
187	*new_resource = NULL;
188	if (pool_type < 0 || pool_type >= FSL_MC_NUM_POOL_TYPES)
189		goto out;
190
191	res_pool = &mc_bus->resource_pools[pool_type];
192	if (res_pool->mc_bus != mc_bus)
193		goto out;
194
195	mutex_lock(&res_pool->mutex);
196	resource = list_first_entry_or_null(&res_pool->free_list,
197					    struct fsl_mc_resource, node);
198
199	if (!resource) {
200		error = -ENXIO;
201		dev_err(&mc_bus_dev->dev,
202			"No more resources of type %s left\n",
203			fsl_mc_pool_type_strings[pool_type]);
204		goto out_unlock;
205	}
206
207	if (resource->type != pool_type)
208		goto out_unlock;
209	if (resource->parent_pool != res_pool)
210		goto out_unlock;
211	if (res_pool->free_count <= 0 ||
212	    res_pool->free_count > res_pool->max_count)
213		goto out_unlock;
214
215	list_del_init(&resource->node);
216
217	res_pool->free_count--;
218	error = 0;
219out_unlock:
220	mutex_unlock(&res_pool->mutex);
221	*new_resource = resource;
222out:
223	return error;
224}
225EXPORT_SYMBOL_GPL(fsl_mc_resource_allocate);
226
227void fsl_mc_resource_free(struct fsl_mc_resource *resource)
228{
229	struct fsl_mc_resource_pool *res_pool;
230
231	res_pool = resource->parent_pool;
232	if (resource->type != res_pool->type)
233		return;
234
235	mutex_lock(&res_pool->mutex);
236	if (res_pool->free_count < 0 ||
237	    res_pool->free_count >= res_pool->max_count)
238		goto out_unlock;
239
240	if (!list_empty(&resource->node))
241		goto out_unlock;
242
243	list_add_tail(&resource->node, &res_pool->free_list);
244	res_pool->free_count++;
245out_unlock:
246	mutex_unlock(&res_pool->mutex);
247}
248EXPORT_SYMBOL_GPL(fsl_mc_resource_free);
249
250/**
251 * fsl_mc_object_allocate - Allocates an fsl-mc object of the given
252 * pool type from a given fsl-mc bus instance
253 *
254 * @mc_dev: fsl-mc device which is used in conjunction with the
255 * allocated object
256 * @pool_type: pool type
257 * @new_mc_dev: pointer to area where the pointer to the allocated device
258 * is to be returned
259 *
260 * Allocatable objects are always used in conjunction with some functional
261 * device.  This function allocates an object of the specified type from
262 * the DPRC containing the functional device.
263 *
264 * NOTE: pool_type must be different from FSL_MC_POOL_MCP, since MC
265 * portals are allocated using fsl_mc_portal_allocate(), instead of
266 * this function.
267 */
268int __must_check fsl_mc_object_allocate(struct fsl_mc_device *mc_dev,
269					enum fsl_mc_pool_type pool_type,
270					struct fsl_mc_device **new_mc_adev)
271{
272	struct fsl_mc_device *mc_bus_dev;
273	struct fsl_mc_bus *mc_bus;
274	struct fsl_mc_device *mc_adev;
275	int error = -EINVAL;
276	struct fsl_mc_resource *resource = NULL;
277
278	*new_mc_adev = NULL;
279	if (mc_dev->flags & FSL_MC_IS_DPRC)
280		goto error;
281
282	if (!dev_is_fsl_mc(mc_dev->dev.parent))
283		goto error;
284
285	if (pool_type == FSL_MC_POOL_DPMCP)
286		goto error;
287
288	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
289	mc_bus = to_fsl_mc_bus(mc_bus_dev);
290	error = fsl_mc_resource_allocate(mc_bus, pool_type, &resource);
291	if (error < 0)
292		goto error;
293
294	mc_adev = resource->data;
295	if (!mc_adev) {
296		error = -EINVAL;
297		goto error;
298	}
299
300	mc_adev->consumer_link = device_link_add(&mc_dev->dev,
301						 &mc_adev->dev,
302						 DL_FLAG_AUTOREMOVE_CONSUMER);
303	if (!mc_adev->consumer_link) {
304		error = -EINVAL;
305		goto error;
306	}
307
308	*new_mc_adev = mc_adev;
309	return 0;
310error:
311	if (resource)
312		fsl_mc_resource_free(resource);
313
314	return error;
315}
316EXPORT_SYMBOL_GPL(fsl_mc_object_allocate);
317
318/**
319 * fsl_mc_object_free - Returns an fsl-mc object to the resource
320 * pool where it came from.
321 * @mc_adev: Pointer to the fsl-mc device
322 */
323void fsl_mc_object_free(struct fsl_mc_device *mc_adev)
324{
325	struct fsl_mc_resource *resource;
326
327	resource = mc_adev->resource;
328	if (resource->type == FSL_MC_POOL_DPMCP)
329		return;
330	if (resource->data != mc_adev)
331		return;
332
333	fsl_mc_resource_free(resource);
334
335	mc_adev->consumer_link = NULL;
336}
337EXPORT_SYMBOL_GPL(fsl_mc_object_free);
338
339/*
340 * A DPRC and the devices in the DPRC all share the same GIC-ITS device
341 * ID.  A block of IRQs is pre-allocated and maintained in a pool
342 * from which devices can allocate them when needed.
343 */
344
345/*
346 * Initialize the interrupt pool associated with an fsl-mc bus.
347 * It allocates a block of IRQs from the GIC-ITS.
348 */
349int fsl_mc_populate_irq_pool(struct fsl_mc_device *mc_bus_dev,
350			     unsigned int irq_count)
351{
352	unsigned int i;
353	struct msi_desc *msi_desc;
354	struct fsl_mc_device_irq *irq_resources;
355	struct fsl_mc_device_irq *mc_dev_irq;
356	int error;
357	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
358	struct fsl_mc_resource_pool *res_pool =
359			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
360
361	/* do nothing if the IRQ pool is already populated */
362	if (mc_bus->irq_resources)
363		return 0;
364
365	if (irq_count == 0 ||
366	    irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS)
367		return -EINVAL;
368
369	error = fsl_mc_msi_domain_alloc_irqs(&mc_bus_dev->dev, irq_count);
370	if (error < 0)
371		return error;
372
373	irq_resources = devm_kcalloc(&mc_bus_dev->dev,
374				     irq_count, sizeof(*irq_resources),
375				     GFP_KERNEL);
376	if (!irq_resources) {
377		error = -ENOMEM;
378		goto cleanup_msi_irqs;
379	}
380
381	for (i = 0; i < irq_count; i++) {
382		mc_dev_irq = &irq_resources[i];
383
384		/*
385		 * NOTE: This mc_dev_irq's MSI addr/value pair will be set
386		 * by the fsl_mc_msi_write_msg() callback
387		 */
388		mc_dev_irq->resource.type = res_pool->type;
389		mc_dev_irq->resource.data = mc_dev_irq;
390		mc_dev_irq->resource.parent_pool = res_pool;
391		INIT_LIST_HEAD(&mc_dev_irq->resource.node);
392		list_add_tail(&mc_dev_irq->resource.node, &res_pool->free_list);
393	}
394
395	for_each_msi_entry(msi_desc, &mc_bus_dev->dev) {
396		mc_dev_irq = &irq_resources[msi_desc->fsl_mc.msi_index];
397		mc_dev_irq->msi_desc = msi_desc;
398		mc_dev_irq->resource.id = msi_desc->irq;
399	}
400
401	res_pool->max_count = irq_count;
402	res_pool->free_count = irq_count;
403	mc_bus->irq_resources = irq_resources;
404	return 0;
405
406cleanup_msi_irqs:
407	fsl_mc_msi_domain_free_irqs(&mc_bus_dev->dev);
408	return error;
409}
410EXPORT_SYMBOL_GPL(fsl_mc_populate_irq_pool);
411
412/**
413 * Teardown the interrupt pool associated with an fsl-mc bus.
414 * It frees the IRQs that were allocated to the pool, back to the GIC-ITS.
415 */
416void fsl_mc_cleanup_irq_pool(struct fsl_mc_device *mc_bus_dev)
417{
418	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
419	struct fsl_mc_resource_pool *res_pool =
420			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
421
422	if (!mc_bus->irq_resources)
423		return;
424
425	if (res_pool->max_count == 0)
426		return;
427
428	if (res_pool->free_count != res_pool->max_count)
429		return;
430
431	INIT_LIST_HEAD(&res_pool->free_list);
432	res_pool->max_count = 0;
433	res_pool->free_count = 0;
434	mc_bus->irq_resources = NULL;
435	fsl_mc_msi_domain_free_irqs(&mc_bus_dev->dev);
436}
437EXPORT_SYMBOL_GPL(fsl_mc_cleanup_irq_pool);
438
439/**
440 * Allocate the IRQs required by a given fsl-mc device.
441 */
442int __must_check fsl_mc_allocate_irqs(struct fsl_mc_device *mc_dev)
443{
444	int i;
445	int irq_count;
446	int res_allocated_count = 0;
447	int error = -EINVAL;
448	struct fsl_mc_device_irq **irqs = NULL;
449	struct fsl_mc_bus *mc_bus;
450	struct fsl_mc_resource_pool *res_pool;
451
452	if (mc_dev->irqs)
453		return -EINVAL;
454
455	irq_count = mc_dev->obj_desc.irq_count;
456	if (irq_count == 0)
457		return -EINVAL;
458
459	if (is_fsl_mc_bus_dprc(mc_dev))
460		mc_bus = to_fsl_mc_bus(mc_dev);
461	else
462		mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
463
464	if (!mc_bus->irq_resources)
465		return -EINVAL;
466
467	res_pool = &mc_bus->resource_pools[FSL_MC_POOL_IRQ];
468	if (res_pool->free_count < irq_count) {
469		dev_err(&mc_dev->dev,
470			"Not able to allocate %u irqs for device\n", irq_count);
471		return -ENOSPC;
472	}
473
474	irqs = devm_kcalloc(&mc_dev->dev, irq_count, sizeof(irqs[0]),
475			    GFP_KERNEL);
476	if (!irqs)
477		return -ENOMEM;
478
479	for (i = 0; i < irq_count; i++) {
480		struct fsl_mc_resource *resource;
481
482		error = fsl_mc_resource_allocate(mc_bus, FSL_MC_POOL_IRQ,
483						 &resource);
484		if (error < 0)
485			goto error_resource_alloc;
486
487		irqs[i] = to_fsl_mc_irq(resource);
488		res_allocated_count++;
489
490		irqs[i]->mc_dev = mc_dev;
491		irqs[i]->dev_irq_index = i;
492	}
493
494	mc_dev->irqs = irqs;
495	return 0;
496
497error_resource_alloc:
498	for (i = 0; i < res_allocated_count; i++) {
499		irqs[i]->mc_dev = NULL;
500		fsl_mc_resource_free(&irqs[i]->resource);
501	}
502
503	return error;
504}
505EXPORT_SYMBOL_GPL(fsl_mc_allocate_irqs);
506
507/*
508 * Frees the IRQs that were allocated for an fsl-mc device.
509 */
510void fsl_mc_free_irqs(struct fsl_mc_device *mc_dev)
511{
512	int i;
513	int irq_count;
514	struct fsl_mc_bus *mc_bus;
515	struct fsl_mc_device_irq **irqs = mc_dev->irqs;
516
517	if (!irqs)
518		return;
519
520	irq_count = mc_dev->obj_desc.irq_count;
521
522	if (is_fsl_mc_bus_dprc(mc_dev))
523		mc_bus = to_fsl_mc_bus(mc_dev);
524	else
525		mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
526
527	if (!mc_bus->irq_resources)
528		return;
529
530	for (i = 0; i < irq_count; i++) {
531		irqs[i]->mc_dev = NULL;
532		fsl_mc_resource_free(&irqs[i]->resource);
533	}
534
535	mc_dev->irqs = NULL;
536}
537EXPORT_SYMBOL_GPL(fsl_mc_free_irqs);
538
539void fsl_mc_init_all_resource_pools(struct fsl_mc_device *mc_bus_dev)
540{
541	int pool_type;
542	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
543
544	for (pool_type = 0; pool_type < FSL_MC_NUM_POOL_TYPES; pool_type++) {
545		struct fsl_mc_resource_pool *res_pool =
546		    &mc_bus->resource_pools[pool_type];
547
548		res_pool->type = pool_type;
549		res_pool->max_count = 0;
550		res_pool->free_count = 0;
551		res_pool->mc_bus = mc_bus;
552		INIT_LIST_HEAD(&res_pool->free_list);
553		mutex_init(&res_pool->mutex);
554	}
555}
556
557static void fsl_mc_cleanup_resource_pool(struct fsl_mc_device *mc_bus_dev,
558					 enum fsl_mc_pool_type pool_type)
559{
560	struct fsl_mc_resource *resource;
561	struct fsl_mc_resource *next;
562	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
563	struct fsl_mc_resource_pool *res_pool =
564					&mc_bus->resource_pools[pool_type];
565	int free_count = 0;
566
567	list_for_each_entry_safe(resource, next, &res_pool->free_list, node) {
568		free_count++;
569		devm_kfree(&mc_bus_dev->dev, resource);
570	}
571}
572
573void fsl_mc_cleanup_all_resource_pools(struct fsl_mc_device *mc_bus_dev)
574{
575	int pool_type;
576
577	for (pool_type = 0; pool_type < FSL_MC_NUM_POOL_TYPES; pool_type++)
578		fsl_mc_cleanup_resource_pool(mc_bus_dev, pool_type);
579}
580
581/**
582 * fsl_mc_allocator_probe - callback invoked when an allocatable device is
583 * being added to the system
584 */
585static int fsl_mc_allocator_probe(struct fsl_mc_device *mc_dev)
586{
587	enum fsl_mc_pool_type pool_type;
588	struct fsl_mc_device *mc_bus_dev;
589	struct fsl_mc_bus *mc_bus;
590	int error;
591
592	if (!fsl_mc_is_allocatable(mc_dev))
593		return -EINVAL;
594
595	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
596	if (!dev_is_fsl_mc(&mc_bus_dev->dev))
597		return -EINVAL;
598
599	mc_bus = to_fsl_mc_bus(mc_bus_dev);
600	error = object_type_to_pool_type(mc_dev->obj_desc.type, &pool_type);
601	if (error < 0)
602		return error;
603
604	error = fsl_mc_resource_pool_add_device(mc_bus, pool_type, mc_dev);
605	if (error < 0)
606		return error;
607
608	dev_dbg(&mc_dev->dev,
609		"Allocatable fsl-mc device bound to fsl_mc_allocator driver");
610	return 0;
611}
612
613/**
614 * fsl_mc_allocator_remove - callback invoked when an allocatable device is
615 * being removed from the system
616 */
617static int fsl_mc_allocator_remove(struct fsl_mc_device *mc_dev)
618{
619	int error;
620
621	if (!fsl_mc_is_allocatable(mc_dev))
622		return -EINVAL;
623
624	if (mc_dev->resource) {
625		error = fsl_mc_resource_pool_remove_device(mc_dev);
626		if (error < 0)
627			return error;
628	}
629
630	dev_dbg(&mc_dev->dev,
631		"Allocatable fsl-mc device unbound from fsl_mc_allocator driver");
632	return 0;
633}
634
635static const struct fsl_mc_device_id match_id_table[] = {
636	{
637	 .vendor = FSL_MC_VENDOR_FREESCALE,
638	 .obj_type = "dpbp",
639	},
640	{
641	 .vendor = FSL_MC_VENDOR_FREESCALE,
642	 .obj_type = "dpmcp",
643	},
644	{
645	 .vendor = FSL_MC_VENDOR_FREESCALE,
646	 .obj_type = "dpcon",
647	},
648	{.vendor = 0x0},
649};
650
651static struct fsl_mc_driver fsl_mc_allocator_driver = {
652	.driver = {
653		   .name = "fsl_mc_allocator",
654		   .pm = NULL,
655		   },
656	.match_id_table = match_id_table,
657	.probe = fsl_mc_allocator_probe,
658	.remove = fsl_mc_allocator_remove,
659};
660
661int __init fsl_mc_allocator_driver_init(void)
662{
663	return fsl_mc_driver_register(&fsl_mc_allocator_driver);
664}
665
666void fsl_mc_allocator_driver_exit(void)
667{
668	fsl_mc_driver_unregister(&fsl_mc_allocator_driver);
669}
670