summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-mips-gic.c
blob: f3985469c2211c7fea4b40469a47c1e27711a510 (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
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2008 Ralf Baechle (ralf@linux-mips.org)
 * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
 */

#define pr_fmt(fmt) "irq-mips-gic: " fmt

#include <linux/bitmap.h>
#include <linux/clocksource.h>
#include <linux/cpuhotplug.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/of_address.h>
#include <linux/percpu.h>
#include <linux/sched.h>
#include <linux/smp.h>

#include <asm/mips-cps.h>
#include <asm/setup.h>
#include <asm/traps.h>

#include <dt-bindings/interrupt-controller/mips-gic.h>

#define GIC_MAX_INTRS		256
#define GIC_MAX_LONGS		BITS_TO_LONGS(GIC_MAX_INTRS)

/* Add 2 to convert GIC CPU pin to core interrupt */
#define GIC_CPU_PIN_OFFSET	2

/* Mapped interrupt to pin X, then GIC will generate the vector (X+1). */
#define GIC_PIN_TO_VEC_OFFSET	1

/* Convert between local/shared IRQ number and GIC HW IRQ number. */
#define GIC_LOCAL_HWIRQ_BASE	0
#define GIC_LOCAL_TO_HWIRQ(x)	(GIC_LOCAL_HWIRQ_BASE + (x))
#define GIC_HWIRQ_TO_LOCAL(x)	((x) - GIC_LOCAL_HWIRQ_BASE)
#define GIC_SHARED_HWIRQ_BASE	GIC_NUM_LOCAL_INTRS
#define GIC_SHARED_TO_HWIRQ(x)	(GIC_SHARED_HWIRQ_BASE + (x))
#define GIC_HWIRQ_TO_SHARED(x)	((x) - GIC_SHARED_HWIRQ_BASE)

void __iomem *mips_gic_base;

DEFINE_PER_CPU_READ_MOSTLY(unsigned long[GIC_MAX_LONGS], pcpu_masks);

static DEFINE_SPINLOCK(gic_lock);
static struct irq_domain *gic_irq_domain;
static struct irq_domain *gic_ipi_domain;
static int gic_shared_intrs;
static unsigned int gic_cpu_pin;
static unsigned int timer_cpu_pin;
static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
static DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
static DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS);

static struct gic_all_vpes_chip_data {
	u32	map;
	bool	mask;
} gic_all_vpes_chip_data[GIC_NUM_LOCAL_INTRS];

static void gic_clear_pcpu_masks(unsigned int intr)
{
	unsigned int i;

	/* Clear the interrupt's bit in all pcpu_masks */
	for_each_possible_cpu(i)
		clear_bit(intr, per_cpu_ptr(pcpu_masks, i));
}

static bool gic_local_irq_is_routable(int intr)
{
	u32 vpe_ctl;

	/* All local interrupts are routable in EIC mode. */
	if (cpu_has_veic)
		return true;

	vpe_ctl = read_gic_vl_ctl();
	switch (intr) {
	case GIC_LOCAL_INT_TIMER:
		return vpe_ctl & GIC_VX_CTL_TIMER_ROUTABLE;
	case GIC_LOCAL_INT_PERFCTR:
		return vpe_ctl & GIC_VX_CTL_PERFCNT_ROUTABLE;
	case GIC_LOCAL_INT_FDC:
		return vpe_ctl & GIC_VX_CTL_FDC_ROUTABLE;
	case GIC_LOCAL_INT_SWINT0:
	case GIC_LOCAL_INT_SWINT1:
		return vpe_ctl & GIC_VX_CTL_SWINT_ROUTABLE;
	default:
		return true;
	}
}

static void gic_bind_eic_interrupt(int irq, int set)
{
	/* Convert irq vector # to hw int # */
	irq -= GIC_PIN_TO_VEC_OFFSET;

	/* Set irq to use shadow set */
	write_gic_vl_eic_shadow_set(irq, set);
}

static void gic_send_ipi(struct irq_data *d, unsigned int cpu)
{
	irq_hw_number_t hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(d));

	write_gic_wedge(GIC_WEDGE_RW | hwirq);
}

int gic_get_c0_compare_int(void)
{
	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
	return irq_create_mapping(gic_irq_domain,
				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
}

int gic_get_c0_perfcount_int(void)
{
	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
		/* Is the performance counter shared with the timer? */
		if (cp0_perfcount_irq < 0)
			return -1;
		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
	}
	return irq_create_mapping(gic_irq_domain,
				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
}

int gic_get_c0_fdc_int(void)
{
	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
		/* Is the FDC IRQ even present? */
		if (cp0_fdc_irq < 0)
			return -1;
		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
	}

	return irq_create_mapping(gic_irq_domain,
				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
}

static void gic_handle_shared_int(bool chained)
{
	unsigned int intr, virq;
	unsigned long *pcpu_mask;
	DECLARE_BITMAP(pending, GIC_MAX_INTRS);

	/* Get per-cpu bitmaps */
	pcpu_mask = this_cpu_ptr(pcpu_masks);

	if (mips_cm_is64)
		__ioread64_copy(pending, addr_gic_pend(),
				DIV_ROUND_UP(gic_shared_intrs, 64));
	else
		__ioread32_copy(pending, addr_gic_pend(),
				DIV_ROUND_UP(gic_shared_intrs, 32));

	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);

	for_each_set_bit(intr, pending, gic_shared_intrs) {
		virq = irq_linear_revmap(gic_irq_domain,
					 GIC_SHARED_TO_HWIRQ(intr));
		if (chained)
			generic_handle_irq(virq);
		else
			do_IRQ(virq);
	}
}

static void gic_mask_irq(struct irq_data *d)
{
	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);

	write_gic_rmask(intr);
	gic_clear_pcpu_masks(intr);
}

static void gic_unmask_irq(struct irq_data *d)
{
	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
	unsigned int cpu;

	write_gic_smask(intr);

	gic_clear_pcpu_masks(intr);
	cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
	set_bit(intr, per_cpu_ptr(pcpu_masks, cpu));
}

static void gic_ack_irq(struct irq_data *d)
{
	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);

	write_gic_wedge(irq);
}

static int gic_set_type(struct irq_data *d, unsigned int type)
{
	unsigned int irq, pol, trig, dual;
	unsigned long flags;

	irq = GIC_HWIRQ_TO_SHARED(d->hwirq);

	spin_lock_irqsave(&gic_lock, flags);
	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQ_TYPE_EDGE_FALLING:
		pol = GIC_POL_FALLING_EDGE;
		trig = GIC_TRIG_EDGE;
		dual = GIC_DUAL_SINGLE;
		break;
	case IRQ_TYPE_EDGE_RISING:
		pol = GIC_POL_RISING_EDGE;
		trig = GIC_TRIG_EDGE;
		dual = GIC_DUAL_SINGLE;
		break;
	case IRQ_TYPE_EDGE_BOTH:
		pol = 0; /* Doesn't matter */
		trig = GIC_TRIG_EDGE;
		dual = GIC_DUAL_DUAL;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		pol = GIC_POL_ACTIVE_LOW;
		trig = GIC_TRIG_LEVEL;
		dual = GIC_DUAL_SINGLE;
		break;
	case IRQ_TYPE_LEVEL_HIGH:
	default:
		pol = GIC_POL_ACTIVE_HIGH;
		trig = GIC_TRIG_LEVEL;
		dual = GIC_DUAL_SINGLE;
		break;
	}

	change_gic_pol(irq, pol);
	change_gic_trig(irq, trig);
	change_gic_dual(irq, dual);

	if (trig == GIC_TRIG_EDGE)
		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
						 handle_edge_irq, NULL);
	else
		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
						 handle_level_irq, NULL);
	spin_unlock_irqrestore(&gic_lock, flags);

	return 0;
}

#ifdef CONFIG_SMP
static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
			    bool force)
{
	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
	unsigned long flags;
	unsigned int cpu;

	cpu = cpumask_first_and(cpumask, cpu_online_mask);
	if (cpu >= NR_CPUS)
		return -EINVAL;

	/* Assumption : cpumask refers to a single CPU */
	spin_lock_irqsave(&gic_lock, flags);

	/* Re-route this IRQ */
	write_gic_map_vp(irq, BIT(mips_cm_vp_id(cpu)));

	/* Update the pcpu_masks */
	gic_clear_pcpu_masks(irq);
	if (read_gic_mask(irq))
		set_bit(irq, per_cpu_ptr(pcpu_masks, cpu));

	irq_data_update_effective_affinity(d, cpumask_of(cpu));
	spin_unlock_irqrestore(&gic_lock, flags);

	return IRQ_SET_MASK_OK;
}
#endif

static struct irq_chip gic_level_irq_controller = {
	.name			=	"MIPS GIC",
	.irq_mask		=	gic_mask_irq,
	.irq_unmask		=	gic_unmask_irq,
	.irq_set_type		=	gic_set_type,
#ifdef CONFIG_SMP
	.irq_set_affinity	=	gic_set_affinity,
#endif
};

static struct irq_chip gic_edge_irq_controller = {
	.name			=	"MIPS GIC",
	.irq_ack		=	gic_ack_irq,
	.irq_mask		=	gic_mask_irq,
	.irq_unmask		=	gic_unmask_irq,
	.irq_set_type		=	gic_set_type,
#ifdef CONFIG_SMP
	.irq_set_affinity	=	gic_set_affinity,
#endif
	.ipi_send_single	=	gic_send_ipi,
};

static void gic_handle_local_int(bool chained)
{
	unsigned long pending, masked;
	unsigned int intr, virq;

	pending = read_gic_vl_pend();
	masked = read_gic_vl_mask();

	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);

	for_each_set_bit(intr, &pending, GIC_NUM_LOCAL_INTRS) {
		virq = irq_linear_revmap(gic_irq_domain,
					 GIC_LOCAL_TO_HWIRQ(intr));
		if (chained)
			generic_handle_irq(virq);
		else
			do_IRQ(virq);
	}
}

static void gic_mask_local_irq(struct irq_data *d)
{
	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);

	write_gic_vl_rmask(BIT(intr));
}

static void gic_unmask_local_irq(struct irq_data *d)
{
	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);

	write_gic_vl_smask(BIT(intr));
}

static struct irq_chip gic_local_irq_controller = {
	.name			=	"MIPS GIC Local",
	.irq_mask		=	gic_mask_local_irq,
	.irq_unmask		=	gic_unmask_local_irq,
};

static void gic_mask_local_irq_all_vpes(struct irq_data *d)
{
	struct gic_all_vpes_chip_data *cd;
	unsigned long flags;
	int intr, cpu;

	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
	cd = irq_data_get_irq_chip_data(d);
	cd->mask = false;

	spin_lock_irqsave(&gic_lock, flags);
	for_each_online_cpu(cpu) {
		write_gic_vl_other(mips_cm_vp_id(cpu));
		write_gic_vo_rmask(BIT(intr));
	}
	spin_unlock_irqrestore(&gic_lock, flags);
}

static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
{
	struct gic_all_vpes_chip_data *cd;
	unsigned long flags;
	int intr, cpu;

	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
	cd = irq_data_get_irq_chip_data(d);
	cd->mask = true;

	spin_lock_irqsave(&gic_lock, flags);
	for_each_online_cpu(cpu) {
		write_gic_vl_other(mips_cm_vp_id(cpu));
		write_gic_vo_smask(BIT(intr));
	}
	spin_unlock_irqrestore(&gic_lock, flags);
}

static void gic_all_vpes_irq_cpu_online(struct irq_data *d)
{
	struct gic_all_vpes_chip_data *cd;
	unsigned int intr;

	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
	cd = irq_data_get_irq_chip_data(d);

	write_gic_vl_map(mips_gic_vx_map_reg(intr), cd->map);
	if (cd->mask)
		write_gic_vl_smask(BIT(intr));
}

static struct irq_chip gic_all_vpes_local_irq_controller = {
	.name			= "MIPS GIC Local",
	.irq_mask		= gic_mask_local_irq_all_vpes,
	.irq_unmask		= gic_unmask_local_irq_all_vpes,
	.irq_cpu_online		= gic_all_vpes_irq_cpu_online,
};

static void __gic_irq_dispatch(void)
{
	gic_handle_local_int(false);
	gic_handle_shared_int(false);
}

static void gic_irq_dispatch(struct irq_desc *desc)
{
	gic_handle_local_int(true);
	gic_handle_shared_int(true);
}

static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
				     irq_hw_number_t hw, unsigned int cpu)
{
	int intr = GIC_HWIRQ_TO_SHARED(hw);
	struct irq_data *data;
	unsigned long flags;

	data = irq_get_irq_data(virq);

	spin_lock_irqsave(&gic_lock, flags);
	write_gic_map_pin(intr, GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
	write_gic_map_vp(intr, BIT(mips_cm_vp_id(cpu)));
	irq_data_update_effective_affinity(data, cpumask_of(cpu));
	spin_unlock_irqrestore(&gic_lock, flags);

	return 0;
}

static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
				const u32 *intspec, unsigned int intsize,
				irq_hw_number_t *out_hwirq,
				unsigned int *out_type)
{
	if (intsize != 3)
		return -EINVAL;

	if (intspec[0] == GIC_SHARED)
		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
	else if (intspec[0] == GIC_LOCAL)
		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
	else
		return -EINVAL;
	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;

	return 0;
}

static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
			      irq_hw_number_t hwirq)
{
	struct gic_all_vpes_chip_data *cd;
	unsigned long flags;
	unsigned int intr;
	int err, cpu;
	u32 map;

	if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
		/* verify that shared irqs don't conflict with an IPI irq */
		if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv))
			return -EBUSY;

		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
						    &gic_level_irq_controller,
						    NULL);
		if (err)
			return err;

		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
		return gic_shared_irq_domain_map(d, virq, hwirq, 0);
	}

	intr = GIC_HWIRQ_TO_LOCAL(hwirq);
	map = GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin;

	switch (intr) {
	case GIC_LOCAL_INT_TIMER:
		/* CONFIG_MIPS_CMP workaround (see __gic_init) */
		map = GIC_MAP_PIN_MAP_TO_PIN | timer_cpu_pin;
		/* fall-through */
	case GIC_LOCAL_INT_PERFCTR:
	case GIC_LOCAL_INT_FDC:
		/*
		 * HACK: These are all really percpu interrupts, but
		 * the rest of the MIPS kernel code does not use the
		 * percpu IRQ API for them.
		 */
		cd = &gic_all_vpes_chip_data[intr];
		cd->map = map;
		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
						    &gic_all_vpes_local_irq_controller,
						    cd);
		if (err)
			return err;

		irq_set_handler(virq, handle_percpu_irq);
		break;

	default:
		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
						    &gic_local_irq_controller,
						    NULL);
		if (err)
			return err;

		irq_set_handler(virq, handle_percpu_devid_irq);
		irq_set_percpu_devid(virq);
		break;
	}

	if (!gic_local_irq_is_routable(intr))
		return -EPERM;

	spin_lock_irqsave(&gic_lock, flags);
	for_each_online_cpu(cpu) {
		write_gic_vl_other(mips_cm_vp_id(cpu));
		write_gic_vo_map(mips_gic_vx_map_reg(intr), map);
	}
	spin_unlock_irqrestore(&gic_lock, flags);

	return 0;
}

static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
				unsigned int nr_irqs, void *arg)
{
	struct irq_fwspec *fwspec = arg;
	irq_hw_number_t hwirq;

	if (fwspec->param[0] == GIC_SHARED)
		hwirq = GIC_SHARED_TO_HWIRQ(fwspec->param[1]);
	else
		hwirq = GIC_LOCAL_TO_HWIRQ(fwspec->param[1]);

	return gic_irq_domain_map(d, virq, hwirq);
}

void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
			 unsigned int nr_irqs)
{
}

static const struct irq_domain_ops gic_irq_domain_ops = {
	.xlate = gic_irq_domain_xlate,
	.alloc = gic_irq_domain_alloc,
	.free = gic_irq_domain_free,
	.map = gic_irq_domain_map,
};

static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
				const u32 *intspec, unsigned int intsize,
				irq_hw_number_t *out_hwirq,
				unsigned int *out_type)
{
	/*
	 * There's nothing to translate here. hwirq is dynamically allocated and
	 * the irq type is always edge triggered.
	 * */
	*out_hwirq = 0;
	*out_type = IRQ_TYPE_EDGE_RISING;

	return 0;
}

static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
				unsigned int nr_irqs, void *arg)
{
	struct cpumask *ipimask = arg;
	irq_hw_number_t hwirq, base_hwirq;
	int cpu, ret, i;

	base_hwirq = find_first_bit(ipi_available, gic_shared_intrs);
	if (base_hwirq == gic_shared_intrs)
		return -ENOMEM;

	/* check that we have enough space */
	for (i = base_hwirq; i < nr_irqs; i++) {
		if (!test_bit(i, ipi_available))
			return -EBUSY;
	}
	bitmap_clear(ipi_available, base_hwirq, nr_irqs);

	/* map the hwirq for each cpu consecutively */
	i = 0;
	for_each_cpu(cpu, ipimask) {
		hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);

		ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
						    &gic_edge_irq_controller,
						    NULL);
		if (ret)
			goto error;

		ret = irq_domain_set_hwirq_and_chip(d->parent, virq + i, hwirq,
						    &gic_edge_irq_controller,
						    NULL);
		if (ret)
			goto error;

		ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
		if (ret)
			goto error;

		ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
		if (ret)
			goto error;

		i++;
	}

	return 0;
error:
	bitmap_set(ipi_available, base_hwirq, nr_irqs);
	return ret;
}

void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
			 unsigned int nr_irqs)
{
	irq_hw_number_t base_hwirq;
	struct irq_data *data;

	data = irq_get_irq_data(virq);
	if (!data)
		return;

	base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
	bitmap_set(ipi_available, base_hwirq, nr_irqs);
}

int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
			 enum irq_domain_bus_token bus_token)
{
	bool is_ipi;

	switch (bus_token) {
	case DOMAIN_BUS_IPI:
		is_ipi = d->bus_token == bus_token;
		return (!node || to_of_node(d->fwnode) == node) && is_ipi;
		break;
	default:
		return 0;
	}
}

static const struct irq_domain_ops gic_ipi_domain_ops = {
	.xlate = gic_ipi_domain_xlate,
	.alloc = gic_ipi_domain_alloc,
	.free = gic_ipi_domain_free,
	.match = gic_ipi_domain_match,
};

static int gic_cpu_startup(unsigned int cpu)
{
	/* Enable or disable EIC */
	change_gic_vl_ctl(GIC_VX_CTL_EIC,
			  cpu_has_veic ? GIC_VX_CTL_EIC : 0);

	/* Clear all local IRQ masks (ie. disable all local interrupts) */
	write_gic_vl_rmask(~0);

	/* Invoke irq_cpu_online callbacks to enable desired interrupts */
	irq_cpu_online();

	return 0;
}

static int __init gic_of_init(struct device_node *node,
			      struct device_node *parent)
{
	unsigned int cpu_vec, i, gicconfig, v[2], num_ipis;
	unsigned long reserved;
	phys_addr_t gic_base;
	struct resource res;
	size_t gic_len;

	/* Find the first available CPU vector. */
	i = 0;
	reserved = (C_SW0 | C_SW1) >> __ffs(C_SW0);
	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
					   i++, &cpu_vec))
		reserved |= BIT(cpu_vec);

	cpu_vec = find_first_zero_bit(&reserved, hweight_long(ST0_IM));
	if (cpu_vec == hweight_long(ST0_IM)) {
		pr_err("No CPU vectors available\n");
		return -ENODEV;
	}

	if (of_address_to_resource(node, 0, &res)) {
		/*
		 * Probe the CM for the GIC base address if not specified
		 * in the device-tree.
		 */
		if (mips_cm_present()) {
			gic_base = read_gcr_gic_base() &
				~CM_GCR_GIC_BASE_GICEN;
			gic_len = 0x20000;
			pr_warn("Using inherited base address %pa\n",
				&gic_base);
		} else {
			pr_err("Failed to get memory range\n");
			return -ENODEV;
		}
	} else {
		gic_base = res.start;
		gic_len = resource_size(&res);
	}

	if (mips_cm_present()) {
		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN);
		/* Ensure GIC region is enabled before trying to access it */
		__sync();
	}

	mips_gic_base = ioremap_nocache(gic_base, gic_len);

	gicconfig = read_gic_config();
	gic_shared_intrs = gicconfig & GIC_CONFIG_NUMINTERRUPTS;
	gic_shared_intrs >>= __ffs(GIC_CONFIG_NUMINTERRUPTS);
	gic_shared_intrs = (gic_shared_intrs + 1) * 8;

	if (cpu_has_veic) {
		/* Always use vector 1 in EIC mode */
		gic_cpu_pin = 0;
		timer_cpu_pin = gic_cpu_pin;
		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
			       __gic_irq_dispatch);
	} else {
		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
					gic_irq_dispatch);
		/*
		 * With the CMP implementation of SMP (deprecated), other CPUs
		 * are started by the bootloader and put into a timer based
		 * waiting poll loop. We must not re-route those CPU's local
		 * timer interrupts as the wait instruction will never finish,
		 * so just handle whatever CPU interrupt it is routed to by
		 * default.
		 *
		 * This workaround should be removed when CMP support is
		 * dropped.
		 */
		if (IS_ENABLED(CONFIG_MIPS_CMP) &&
		    gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER)) {
			timer_cpu_pin = read_gic_vl_timer_map() & GIC_MAP_PIN_MAP;
			irq_set_chained_handler(MIPS_CPU_IRQ_BASE +
						GIC_CPU_PIN_OFFSET +
						timer_cpu_pin,
						gic_irq_dispatch);
		} else {
			timer_cpu_pin = gic_cpu_pin;
		}
	}

	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
					       gic_shared_intrs, 0,
					       &gic_irq_domain_ops, NULL);
	if (!gic_irq_domain) {
		pr_err("Failed to add IRQ domain");
		return -ENXIO;
	}

	gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain,
						  IRQ_DOMAIN_FLAG_IPI_PER_CPU,
						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
						  node, &gic_ipi_domain_ops, NULL);
	if (!gic_ipi_domain) {
		pr_err("Failed to add IPI domain");
		return -ENXIO;
	}

	irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);

	if (node &&
	    !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
		bitmap_set(ipi_resrv, v[0], v[1]);
	} else {
		/*
		 * Reserve 2 interrupts per possible CPU/VP for use as IPIs,
		 * meeting the requirements of arch/mips SMP.
		 */
		num_ipis = 2 * num_possible_cpus();
		bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis);
	}

	bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);

	board_bind_eic_interrupt = &gic_bind_eic_interrupt;

	/* Setup defaults */
	for (i = 0; i < gic_shared_intrs; i++) {
		change_gic_pol(i, GIC_POL_ACTIVE_HIGH);
		change_gic_trig(i, GIC_TRIG_LEVEL);
		write_gic_rmask(i);
	}

	return cpuhp_setup_state(CPUHP_AP_IRQ_MIPS_GIC_STARTING,
				 "irqchip/mips/gic:starting",
				 gic_cpu_startup, NULL);
}
IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);