summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-ti-sci-inta.c
blob: ca1f593f4d13aa2fd39db911cb230d818fa365ec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
// SPDX-License-Identifier: GPL-2.0
/*
 * Texas Instruments' K3 Interrupt Aggregator irqchip driver
 *
 * Copyright (C) 2018-2019 Texas Instruments Incorporated - https://www.ti.com/
 *	Lokesh Vutla <lokeshvutla@ti.com>
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/soc/ti/ti_sci_inta_msi.h>
#include <linux/soc/ti/ti_sci_protocol.h>
#include <asm-generic/msi.h>

#define TI_SCI_DEV_ID_MASK	0xffff
#define TI_SCI_DEV_ID_SHIFT	16
#define TI_SCI_IRQ_ID_MASK	0xffff
#define TI_SCI_IRQ_ID_SHIFT	0
#define HWIRQ_TO_DEVID(hwirq)	(((hwirq) >> (TI_SCI_DEV_ID_SHIFT)) & \
				 (TI_SCI_DEV_ID_MASK))
#define HWIRQ_TO_IRQID(hwirq)	((hwirq) & (TI_SCI_IRQ_ID_MASK))
#define TO_HWIRQ(dev, index)	((((dev) & TI_SCI_DEV_ID_MASK) << \
				 TI_SCI_DEV_ID_SHIFT) | \
				((index) & TI_SCI_IRQ_ID_MASK))

#define MAX_EVENTS_PER_VINT	64
#define VINT_ENABLE_SET_OFFSET	0x0
#define VINT_ENABLE_CLR_OFFSET	0x8
#define VINT_STATUS_OFFSET	0x18
#define VINT_STATUS_MASKED_OFFSET	0x20

/**
 * struct ti_sci_inta_event_desc - Description of an event coming to
 *				   Interrupt Aggregator. This serves
 *				   as a mapping table for global event,
 *				   hwirq and vint bit.
 * @global_event:	Global event number corresponding to this event
 * @hwirq:		Hwirq of the incoming interrupt
 * @vint_bit:		Corresponding vint bit to which this event is attached.
 */
struct ti_sci_inta_event_desc {
	u16 global_event;
	u32 hwirq;
	u8 vint_bit;
};

/**
 * struct ti_sci_inta_vint_desc - Description of a virtual interrupt coming out
 *				  of Interrupt Aggregator.
 * @domain:		Pointer to IRQ domain to which this vint belongs.
 * @list:		List entry for the vint list
 * @event_map:		Bitmap to manage the allocation of events to vint.
 * @events:		Array of event descriptors assigned to this vint.
 * @parent_virq:	Linux IRQ number that gets attached to parent
 * @vint_id:		TISCI vint ID
 */
struct ti_sci_inta_vint_desc {
	struct irq_domain *domain;
	struct list_head list;
	DECLARE_BITMAP(event_map, MAX_EVENTS_PER_VINT);
	struct ti_sci_inta_event_desc events[MAX_EVENTS_PER_VINT];
	unsigned int parent_virq;
	u16 vint_id;
};

/**
 * struct ti_sci_inta_irq_domain - Structure representing a TISCI based
 *				   Interrupt Aggregator IRQ domain.
 * @sci:		Pointer to TISCI handle
 * @vint:		TISCI resource pointer representing IA interrupts.
 * @global_event:	TISCI resource pointer representing global events.
 * @vint_list:		List of the vints active in the system
 * @vint_mutex:		Mutex to protect vint_list
 * @base:		Base address of the memory mapped IO registers
 * @pdev:		Pointer to platform device.
 * @ti_sci_id:		TI-SCI device identifier
 * @unmapped_cnt:	Number of @unmapped_dev_ids entries
 * @unmapped_dev_ids:	Pointer to an array of TI-SCI device identifiers of
 *			unmapped event sources.
 *			Unmapped Events are not part of the Global Event Map and
 *			they are converted to Global event within INTA to be
 *			received by the same INTA to generate an interrupt.
 *			In case an interrupt request comes for a device which is
 *			generating Unmapped Event, we must use the INTA's TI-SCI
 *			device identifier in place of the source device
 *			identifier to let sysfw know where it has to program the
 *			Global Event number.
 */
struct ti_sci_inta_irq_domain {
	const struct ti_sci_handle *sci;
	struct ti_sci_resource *vint;
	struct ti_sci_resource *global_event;
	struct list_head vint_list;
	/* Mutex to protect vint list */
	struct mutex vint_mutex;
	void __iomem *base;
	struct platform_device *pdev;
	u32 ti_sci_id;

	int unmapped_cnt;
	u16 *unmapped_dev_ids;
};

#define to_vint_desc(e, i) container_of(e, struct ti_sci_inta_vint_desc, \
					events[i])

static u16 ti_sci_inta_get_dev_id(struct ti_sci_inta_irq_domain *inta, u32 hwirq)
{
	u16 dev_id = HWIRQ_TO_DEVID(hwirq);
	int i;

	if (inta->unmapped_cnt == 0)
		return dev_id;

	/*
	 * For devices sending Unmapped Events we must use the INTA's TI-SCI
	 * device identifier number to be able to convert it to a Global Event
	 * and map it to an interrupt.
	 */
	for (i = 0; i < inta->unmapped_cnt; i++) {
		if (dev_id == inta->unmapped_dev_ids[i]) {
			dev_id = inta->ti_sci_id;
			break;
		}
	}

	return dev_id;
}

/**
 * ti_sci_inta_irq_handler() - Chained IRQ handler for the vint irqs
 * @desc:	Pointer to irq_desc corresponding to the irq
 */
static void ti_sci_inta_irq_handler(struct irq_desc *desc)
{
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;
	struct irq_domain *domain;
	unsigned int virq, bit;
	unsigned long val;

	vint_desc = irq_desc_get_handler_data(desc);
	domain = vint_desc->domain;
	inta = domain->host_data;

	chained_irq_enter(irq_desc_get_chip(desc), desc);

	val = readq_relaxed(inta->base + vint_desc->vint_id * 0x1000 +
			    VINT_STATUS_MASKED_OFFSET);

	for_each_set_bit(bit, &val, MAX_EVENTS_PER_VINT) {
		virq = irq_find_mapping(domain, vint_desc->events[bit].hwirq);
		if (virq)
			generic_handle_irq(virq);
	}

	chained_irq_exit(irq_desc_get_chip(desc), desc);
}

/**
 * ti_sci_inta_xlate_irq() - Translate hwirq to parent's hwirq.
 * @inta:	IRQ domain corresponding to Interrupt Aggregator
 * @irq:	Hardware irq corresponding to the above irq domain
 *
 * Return parent irq number if translation is available else -ENOENT.
 */
static int ti_sci_inta_xlate_irq(struct ti_sci_inta_irq_domain *inta,
				 u16 vint_id)
{
	struct device_node *np = dev_of_node(&inta->pdev->dev);
	u32 base, parent_base, size;
	const __be32 *range;
	int len;

	range = of_get_property(np, "ti,interrupt-ranges", &len);
	if (!range)
		return vint_id;

	for (len /= sizeof(*range); len >= 3; len -= 3) {
		base = be32_to_cpu(*range++);
		parent_base = be32_to_cpu(*range++);
		size = be32_to_cpu(*range++);

		if (base <= vint_id && vint_id < base + size)
			return vint_id - base + parent_base;
	}

	return -ENOENT;
}

/**
 * ti_sci_inta_alloc_parent_irq() - Allocate parent irq to Interrupt aggregator
 * @domain:	IRQ domain corresponding to Interrupt Aggregator
 *
 * Return 0 if all went well else corresponding error value.
 */
static struct ti_sci_inta_vint_desc *ti_sci_inta_alloc_parent_irq(struct irq_domain *domain)
{
	struct ti_sci_inta_irq_domain *inta = domain->host_data;
	struct ti_sci_inta_vint_desc *vint_desc;
	struct irq_fwspec parent_fwspec;
	struct device_node *parent_node;
	unsigned int parent_virq;
	int p_hwirq, ret;
	u16 vint_id;

	vint_id = ti_sci_get_free_resource(inta->vint);
	if (vint_id == TI_SCI_RESOURCE_NULL)
		return ERR_PTR(-EINVAL);

	p_hwirq = ti_sci_inta_xlate_irq(inta, vint_id);
	if (p_hwirq < 0) {
		ret = p_hwirq;
		goto free_vint;
	}

	vint_desc = kzalloc(sizeof(*vint_desc), GFP_KERNEL);
	if (!vint_desc) {
		ret = -ENOMEM;
		goto free_vint;
	}

	vint_desc->domain = domain;
	vint_desc->vint_id = vint_id;
	INIT_LIST_HEAD(&vint_desc->list);

	parent_node = of_irq_find_parent(dev_of_node(&inta->pdev->dev));
	parent_fwspec.fwnode = of_node_to_fwnode(parent_node);

	if (of_device_is_compatible(parent_node, "arm,gic-v3")) {
		/* Parent is GIC */
		parent_fwspec.param_count = 3;
		parent_fwspec.param[0] = 0;
		parent_fwspec.param[1] = p_hwirq - 32;
		parent_fwspec.param[2] = IRQ_TYPE_LEVEL_HIGH;
	} else {
		/* Parent is Interrupt Router */
		parent_fwspec.param_count = 1;
		parent_fwspec.param[0] = p_hwirq;
	}

	parent_virq = irq_create_fwspec_mapping(&parent_fwspec);
	if (parent_virq == 0) {
		dev_err(&inta->pdev->dev, "Parent IRQ allocation failed\n");
		ret = -EINVAL;
		goto free_vint_desc;

	}
	vint_desc->parent_virq = parent_virq;

	list_add_tail(&vint_desc->list, &inta->vint_list);
	irq_set_chained_handler_and_data(vint_desc->parent_virq,
					 ti_sci_inta_irq_handler, vint_desc);

	return vint_desc;
free_vint_desc:
	kfree(vint_desc);
free_vint:
	ti_sci_release_resource(inta->vint, vint_id);
	return ERR_PTR(ret);
}

/**
 * ti_sci_inta_alloc_event() - Attach an event to a IA vint.
 * @vint_desc:	Pointer to vint_desc to which the event gets attached
 * @free_bit:	Bit inside vint to which event gets attached
 * @hwirq:	hwirq of the input event
 *
 * Return event_desc pointer if all went ok else appropriate error value.
 */
static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_event(struct ti_sci_inta_vint_desc *vint_desc,
							      u16 free_bit,
							      u32 hwirq)
{
	struct ti_sci_inta_irq_domain *inta = vint_desc->domain->host_data;
	struct ti_sci_inta_event_desc *event_desc;
	u16 dev_id, dev_index;
	int err;

	dev_id = ti_sci_inta_get_dev_id(inta, hwirq);
	dev_index = HWIRQ_TO_IRQID(hwirq);

	event_desc = &vint_desc->events[free_bit];
	event_desc->hwirq = hwirq;
	event_desc->vint_bit = free_bit;
	event_desc->global_event = ti_sci_get_free_resource(inta->global_event);
	if (event_desc->global_event == TI_SCI_RESOURCE_NULL)
		return ERR_PTR(-EINVAL);

	err = inta->sci->ops.rm_irq_ops.set_event_map(inta->sci,
						      dev_id, dev_index,
						      inta->ti_sci_id,
						      vint_desc->vint_id,
						      event_desc->global_event,
						      free_bit);
	if (err)
		goto free_global_event;

	return event_desc;
free_global_event:
	ti_sci_release_resource(inta->global_event, event_desc->global_event);
	return ERR_PTR(err);
}

/**
 * ti_sci_inta_alloc_irq() -  Allocate an irq within INTA domain
 * @domain:	irq_domain pointer corresponding to INTA
 * @hwirq:	hwirq of the input event
 *
 * Note: Allocation happens in the following manner:
 *	- Find a free bit available in any of the vints available in the list.
 *	- If not found, allocate a vint from the vint pool
 *	- Attach the free bit to input hwirq.
 * Return event_desc if all went ok else appropriate error value.
 */
static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_irq(struct irq_domain *domain,
							    u32 hwirq)
{
	struct ti_sci_inta_irq_domain *inta = domain->host_data;
	struct ti_sci_inta_vint_desc *vint_desc = NULL;
	struct ti_sci_inta_event_desc *event_desc;
	u16 free_bit;

	mutex_lock(&inta->vint_mutex);
	list_for_each_entry(vint_desc, &inta->vint_list, list) {
		free_bit = find_first_zero_bit(vint_desc->event_map,
					       MAX_EVENTS_PER_VINT);
		if (free_bit != MAX_EVENTS_PER_VINT) {
			set_bit(free_bit, vint_desc->event_map);
			goto alloc_event;
		}
	}

	/* No free bits available. Allocate a new vint */
	vint_desc = ti_sci_inta_alloc_parent_irq(domain);
	if (IS_ERR(vint_desc)) {
		event_desc = ERR_CAST(vint_desc);
		goto unlock;
	}

	free_bit = find_first_zero_bit(vint_desc->event_map,
				       MAX_EVENTS_PER_VINT);
	set_bit(free_bit, vint_desc->event_map);

alloc_event:
	event_desc = ti_sci_inta_alloc_event(vint_desc, free_bit, hwirq);
	if (IS_ERR(event_desc))
		clear_bit(free_bit, vint_desc->event_map);

unlock:
	mutex_unlock(&inta->vint_mutex);
	return event_desc;
}

/**
 * ti_sci_inta_free_parent_irq() - Free a parent irq to INTA
 * @inta:	Pointer to inta domain.
 * @vint_desc:	Pointer to vint_desc that needs to be freed.
 */
static void ti_sci_inta_free_parent_irq(struct ti_sci_inta_irq_domain *inta,
					struct ti_sci_inta_vint_desc *vint_desc)
{
	if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) == MAX_EVENTS_PER_VINT) {
		list_del(&vint_desc->list);
		ti_sci_release_resource(inta->vint, vint_desc->vint_id);
		irq_dispose_mapping(vint_desc->parent_virq);
		kfree(vint_desc);
	}
}

/**
 * ti_sci_inta_free_irq() - Free an IRQ within INTA domain
 * @event_desc:	Pointer to event_desc that needs to be freed.
 * @hwirq:	Hwirq number within INTA domain that needs to be freed
 */
static void ti_sci_inta_free_irq(struct ti_sci_inta_event_desc *event_desc,
				 u32 hwirq)
{
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;
	u16 dev_id;

	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
	inta = vint_desc->domain->host_data;
	dev_id = ti_sci_inta_get_dev_id(inta, hwirq);
	/* free event irq */
	mutex_lock(&inta->vint_mutex);
	inta->sci->ops.rm_irq_ops.free_event_map(inta->sci,
						 dev_id, HWIRQ_TO_IRQID(hwirq),
						 inta->ti_sci_id,
						 vint_desc->vint_id,
						 event_desc->global_event,
						 event_desc->vint_bit);

	clear_bit(event_desc->vint_bit, vint_desc->event_map);
	ti_sci_release_resource(inta->global_event, event_desc->global_event);
	event_desc->global_event = TI_SCI_RESOURCE_NULL;
	event_desc->hwirq = 0;

	ti_sci_inta_free_parent_irq(inta, vint_desc);
	mutex_unlock(&inta->vint_mutex);
}

/**
 * ti_sci_inta_request_resources() - Allocate resources for input irq
 * @data: Pointer to corresponding irq_data
 *
 * Note: This is the core api where the actual allocation happens for input
 *	 hwirq. This allocation involves creating a parent irq for vint.
 *	 If this is done in irq_domain_ops.alloc() then a deadlock is reached
 *	 for allocation. So this allocation is being done in request_resources()
 *
 * Return: 0 if all went well else corresponding error.
 */
static int ti_sci_inta_request_resources(struct irq_data *data)
{
	struct ti_sci_inta_event_desc *event_desc;

	event_desc = ti_sci_inta_alloc_irq(data->domain, data->hwirq);
	if (IS_ERR(event_desc))
		return PTR_ERR(event_desc);

	data->chip_data = event_desc;

	return 0;
}

/**
 * ti_sci_inta_release_resources - Release resources for input irq
 * @data: Pointer to corresponding irq_data
 *
 * Note: Corresponding to request_resources(), all the unmapping and deletion
 *	 of parent vint irqs happens in this api.
 */
static void ti_sci_inta_release_resources(struct irq_data *data)
{
	struct ti_sci_inta_event_desc *event_desc;

	event_desc = irq_data_get_irq_chip_data(data);
	ti_sci_inta_free_irq(event_desc, data->hwirq);
}

/**
 * ti_sci_inta_manage_event() - Control the event based on the offset
 * @data:	Pointer to corresponding irq_data
 * @offset:	register offset using which event is controlled.
 */
static void ti_sci_inta_manage_event(struct irq_data *data, u32 offset)
{
	struct ti_sci_inta_event_desc *event_desc;
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;

	event_desc = irq_data_get_irq_chip_data(data);
	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
	inta = data->domain->host_data;

	writeq_relaxed(BIT(event_desc->vint_bit),
		       inta->base + vint_desc->vint_id * 0x1000 + offset);
}

/**
 * ti_sci_inta_mask_irq() - Mask an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_mask_irq(struct irq_data *data)
{
	ti_sci_inta_manage_event(data, VINT_ENABLE_CLR_OFFSET);
}

/**
 * ti_sci_inta_unmask_irq() - Unmask an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_unmask_irq(struct irq_data *data)
{
	ti_sci_inta_manage_event(data, VINT_ENABLE_SET_OFFSET);
}

/**
 * ti_sci_inta_ack_irq() - Ack an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_ack_irq(struct irq_data *data)
{
	/*
	 * Do not clear the event if hardware is capable of sending
	 * a down event.
	 */
	if (irqd_get_trigger_type(data) != IRQF_TRIGGER_HIGH)
		ti_sci_inta_manage_event(data, VINT_STATUS_OFFSET);
}

static int ti_sci_inta_set_affinity(struct irq_data *d,
				    const struct cpumask *mask_val, bool force)
{
	return -EINVAL;
}

/**
 * ti_sci_inta_set_type() - Update the trigger type of the irq.
 * @data:	Pointer to corresponding irq_data
 * @type:	Trigger type as specified by user
 *
 * Note: This updates the handle_irq callback for level msi.
 *
 * Return 0 if all went well else appropriate error.
 */
static int ti_sci_inta_set_type(struct irq_data *data, unsigned int type)
{
	/*
	 * .alloc default sets handle_edge_irq. But if the user specifies
	 * that IRQ is level MSI, then update the handle to handle_level_irq
	 */
	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQF_TRIGGER_HIGH:
		irq_set_handler_locked(data, handle_level_irq);
		return 0;
	case IRQF_TRIGGER_RISING:
		return 0;
	default:
		return -EINVAL;
	}
}

static struct irq_chip ti_sci_inta_irq_chip = {
	.name			= "INTA",
	.irq_ack		= ti_sci_inta_ack_irq,
	.irq_mask		= ti_sci_inta_mask_irq,
	.irq_set_type		= ti_sci_inta_set_type,
	.irq_unmask		= ti_sci_inta_unmask_irq,
	.irq_set_affinity	= ti_sci_inta_set_affinity,
	.irq_request_resources	= ti_sci_inta_request_resources,
	.irq_release_resources	= ti_sci_inta_release_resources,
};

/**
 * ti_sci_inta_irq_domain_free() - Free an IRQ from the IRQ domain
 * @domain:	Domain to which the irqs belong
 * @virq:	base linux virtual IRQ to be freed.
 * @nr_irqs:	Number of continuous irqs to be freed
 */
static void ti_sci_inta_irq_domain_free(struct irq_domain *domain,
					unsigned int virq, unsigned int nr_irqs)
{
	struct irq_data *data = irq_domain_get_irq_data(domain, virq);

	irq_domain_reset_irq_data(data);
}

/**
 * ti_sci_inta_irq_domain_alloc() - Allocate Interrupt aggregator IRQs
 * @domain:	Point to the interrupt aggregator IRQ domain
 * @virq:	Corresponding Linux virtual IRQ number
 * @nr_irqs:	Continuous irqs to be allocated
 * @data:	Pointer to firmware specifier
 *
 * No actual allocation happens here.
 *
 * Return 0 if all went well else appropriate error value.
 */
static int ti_sci_inta_irq_domain_alloc(struct irq_domain *domain,
					unsigned int virq, unsigned int nr_irqs,
					void *data)
{
	msi_alloc_info_t *arg = data;

	irq_domain_set_info(domain, virq, arg->hwirq, &ti_sci_inta_irq_chip,
			    NULL, handle_edge_irq, NULL, NULL);

	return 0;
}

static const struct irq_domain_ops ti_sci_inta_irq_domain_ops = {
	.free		= ti_sci_inta_irq_domain_free,
	.alloc		= ti_sci_inta_irq_domain_alloc,
};

static struct irq_chip ti_sci_inta_msi_irq_chip = {
	.name			= "MSI-INTA",
	.flags			= IRQCHIP_SUPPORTS_LEVEL_MSI,
};

static void ti_sci_inta_msi_set_desc(msi_alloc_info_t *arg,
				     struct msi_desc *desc)
{
	struct platform_device *pdev = to_platform_device(desc->dev);

	arg->desc = desc;
	arg->hwirq = TO_HWIRQ(pdev->id, desc->inta.dev_index);
}

static struct msi_domain_ops ti_sci_inta_msi_ops = {
	.set_desc	= ti_sci_inta_msi_set_desc,
};

static struct msi_domain_info ti_sci_inta_msi_domain_info = {
	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
		   MSI_FLAG_LEVEL_CAPABLE),
	.ops	= &ti_sci_inta_msi_ops,
	.chip	= &ti_sci_inta_msi_irq_chip,
};

static int ti_sci_inta_get_unmapped_sources(struct ti_sci_inta_irq_domain *inta)
{
	struct device *dev = &inta->pdev->dev;
	struct device_node *node = dev_of_node(dev);
	struct of_phandle_iterator it;
	int count, err, ret, i;

	count = of_count_phandle_with_args(node, "ti,unmapped-event-sources", NULL);
	if (count <= 0)
		return 0;

	inta->unmapped_dev_ids = devm_kcalloc(dev, count,
					      sizeof(*inta->unmapped_dev_ids),
					      GFP_KERNEL);
	if (!inta->unmapped_dev_ids)
		return -ENOMEM;

	i = 0;
	of_for_each_phandle(&it, err, node, "ti,unmapped-event-sources", NULL, 0) {
		u32 dev_id;

		ret = of_property_read_u32(it.node, "ti,sci-dev-id", &dev_id);
		if (ret) {
			dev_err(dev, "ti,sci-dev-id read failure for %pOFf\n", it.node);
			of_node_put(it.node);
			return ret;
		}
		inta->unmapped_dev_ids[i++] = dev_id;
	}

	inta->unmapped_cnt = count;

	return 0;
}

static int ti_sci_inta_irq_domain_probe(struct platform_device *pdev)
{
	struct irq_domain *parent_domain, *domain, *msi_domain;
	struct device_node *parent_node, *node;
	struct ti_sci_inta_irq_domain *inta;
	struct device *dev = &pdev->dev;
	struct resource *res;
	int ret;

	node = dev_of_node(dev);
	parent_node = of_irq_find_parent(node);
	if (!parent_node) {
		dev_err(dev, "Failed to get IRQ parent node\n");
		return -ENODEV;
	}

	parent_domain = irq_find_host(parent_node);
	if (!parent_domain)
		return -EPROBE_DEFER;

	inta = devm_kzalloc(dev, sizeof(*inta), GFP_KERNEL);
	if (!inta)
		return -ENOMEM;

	inta->pdev = pdev;
	inta->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
	if (IS_ERR(inta->sci))
		return dev_err_probe(dev, PTR_ERR(inta->sci),
				     "ti,sci read fail\n");

	ret = of_property_read_u32(dev->of_node, "ti,sci-dev-id", &inta->ti_sci_id);
	if (ret) {
		dev_err(dev, "missing 'ti,sci-dev-id' property\n");
		return -EINVAL;
	}

	inta->vint = devm_ti_sci_get_resource(inta->sci, dev, inta->ti_sci_id,
					      TI_SCI_RESASG_SUBTYPE_IA_VINT);
	if (IS_ERR(inta->vint)) {
		dev_err(dev, "VINT resource allocation failed\n");
		return PTR_ERR(inta->vint);
	}

	inta->global_event = devm_ti_sci_get_resource(inta->sci, dev, inta->ti_sci_id,
						      TI_SCI_RESASG_SUBTYPE_GLOBAL_EVENT_SEVT);
	if (IS_ERR(inta->global_event)) {
		dev_err(dev, "Global event resource allocation failed\n");
		return PTR_ERR(inta->global_event);
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	inta->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(inta->base))
		return PTR_ERR(inta->base);

	ret = ti_sci_inta_get_unmapped_sources(inta);
	if (ret)
		return ret;

	domain = irq_domain_add_linear(dev_of_node(dev),
				       ti_sci_get_num_resources(inta->vint),
				       &ti_sci_inta_irq_domain_ops, inta);
	if (!domain) {
		dev_err(dev, "Failed to allocate IRQ domain\n");
		return -ENOMEM;
	}

	msi_domain = ti_sci_inta_msi_create_irq_domain(of_node_to_fwnode(node),
						&ti_sci_inta_msi_domain_info,
						domain);
	if (!msi_domain) {
		irq_domain_remove(domain);
		dev_err(dev, "Failed to allocate msi domain\n");
		return -ENOMEM;
	}

	INIT_LIST_HEAD(&inta->vint_list);
	mutex_init(&inta->vint_mutex);

	dev_info(dev, "Interrupt Aggregator domain %d created\n", inta->ti_sci_id);

	return 0;
}

static const struct of_device_id ti_sci_inta_irq_domain_of_match[] = {
	{ .compatible = "ti,sci-inta", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, ti_sci_inta_irq_domain_of_match);

static struct platform_driver ti_sci_inta_irq_domain_driver = {
	.probe = ti_sci_inta_irq_domain_probe,
	.driver = {
		.name = "ti-sci-inta",
		.of_match_table = ti_sci_inta_irq_domain_of_match,
	},
};
module_platform_driver(ti_sci_inta_irq_domain_driver);

MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ti.com>");
MODULE_DESCRIPTION("K3 Interrupt Aggregator driver over TI SCI protocol");
MODULE_LICENSE("GPL v2");