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