1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008 Ralf Baechle (ralf@linux-mips.org)
7  * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
8  */
9 
10 #define pr_fmt(fmt) "irq-mips-gic: " fmt
11 
12 #include <linux/bitfield.h>
13 #include <linux/bitmap.h>
14 #include <linux/clocksource.h>
15 #include <linux/cpuhotplug.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/irq.h>
19 #include <linux/irqchip.h>
20 #include <linux/irqdomain.h>
21 #include <linux/of_address.h>
22 #include <linux/percpu.h>
23 #include <linux/sched.h>
24 #include <linux/smp.h>
25 
26 #include <asm/mips-cps.h>
27 #include <asm/setup.h>
28 #include <asm/traps.h>
29 
30 #include <dt-bindings/interrupt-controller/mips-gic.h>
31 
32 #define GIC_MAX_INTRS		256
33 #define GIC_MAX_LONGS		BITS_TO_LONGS(GIC_MAX_INTRS)
34 
35 /* Add 2 to convert GIC CPU pin to core interrupt */
36 #define GIC_CPU_PIN_OFFSET	2
37 
38 /* Mapped interrupt to pin X, then GIC will generate the vector (X+1). */
39 #define GIC_PIN_TO_VEC_OFFSET	1
40 
41 /* Convert between local/shared IRQ number and GIC HW IRQ number. */
42 #define GIC_LOCAL_HWIRQ_BASE	0
43 #define GIC_LOCAL_TO_HWIRQ(x)	(GIC_LOCAL_HWIRQ_BASE + (x))
44 #define GIC_HWIRQ_TO_LOCAL(x)	((x) - GIC_LOCAL_HWIRQ_BASE)
45 #define GIC_SHARED_HWIRQ_BASE	GIC_NUM_LOCAL_INTRS
46 #define GIC_SHARED_TO_HWIRQ(x)	(GIC_SHARED_HWIRQ_BASE + (x))
47 #define GIC_HWIRQ_TO_SHARED(x)	((x) - GIC_SHARED_HWIRQ_BASE)
48 
49 void __iomem *mips_gic_base;
50 
51 static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[GIC_MAX_LONGS], pcpu_masks);
52 
53 static DEFINE_SPINLOCK(gic_lock);
54 static struct irq_domain *gic_irq_domain;
55 static struct irq_domain *gic_ipi_domain;
56 static int gic_shared_intrs;
57 static unsigned int gic_cpu_pin;
58 static unsigned int timer_cpu_pin;
59 static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
60 static DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
61 static DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS);
62 
63 static struct gic_all_vpes_chip_data {
64 	u32	map;
65 	bool	mask;
66 } gic_all_vpes_chip_data[GIC_NUM_LOCAL_INTRS];
67 
68 static void gic_clear_pcpu_masks(unsigned int intr)
69 {
70 	unsigned int i;
71 
72 	/* Clear the interrupt's bit in all pcpu_masks */
73 	for_each_possible_cpu(i)
74 		clear_bit(intr, per_cpu_ptr(pcpu_masks, i));
75 }
76 
77 static bool gic_local_irq_is_routable(int intr)
78 {
79 	u32 vpe_ctl;
80 
81 	/* All local interrupts are routable in EIC mode. */
82 	if (cpu_has_veic)
83 		return true;
84 
85 	vpe_ctl = read_gic_vl_ctl();
86 	switch (intr) {
87 	case GIC_LOCAL_INT_TIMER:
88 		return vpe_ctl & GIC_VX_CTL_TIMER_ROUTABLE;
89 	case GIC_LOCAL_INT_PERFCTR:
90 		return vpe_ctl & GIC_VX_CTL_PERFCNT_ROUTABLE;
91 	case GIC_LOCAL_INT_FDC:
92 		return vpe_ctl & GIC_VX_CTL_FDC_ROUTABLE;
93 	case GIC_LOCAL_INT_SWINT0:
94 	case GIC_LOCAL_INT_SWINT1:
95 		return vpe_ctl & GIC_VX_CTL_SWINT_ROUTABLE;
96 	default:
97 		return true;
98 	}
99 }
100 
101 static void gic_bind_eic_interrupt(int irq, int set)
102 {
103 	/* Convert irq vector # to hw int # */
104 	irq -= GIC_PIN_TO_VEC_OFFSET;
105 
106 	/* Set irq to use shadow set */
107 	write_gic_vl_eic_shadow_set(irq, set);
108 }
109 
110 static void gic_send_ipi(struct irq_data *d, unsigned int cpu)
111 {
112 	irq_hw_number_t hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(d));
113 
114 	write_gic_wedge(GIC_WEDGE_RW | hwirq);
115 }
116 
117 int gic_get_c0_compare_int(void)
118 {
119 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
120 		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
121 	return irq_create_mapping(gic_irq_domain,
122 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
123 }
124 
125 int gic_get_c0_perfcount_int(void)
126 {
127 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
128 		/* Is the performance counter shared with the timer? */
129 		if (cp0_perfcount_irq < 0)
130 			return -1;
131 		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
132 	}
133 	return irq_create_mapping(gic_irq_domain,
134 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
135 }
136 
137 int gic_get_c0_fdc_int(void)
138 {
139 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
140 		/* Is the FDC IRQ even present? */
141 		if (cp0_fdc_irq < 0)
142 			return -1;
143 		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
144 	}
145 
146 	return irq_create_mapping(gic_irq_domain,
147 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
148 }
149 
150 static void gic_handle_shared_int(bool chained)
151 {
152 	unsigned int intr;
153 	unsigned long *pcpu_mask;
154 	DECLARE_BITMAP(pending, GIC_MAX_INTRS);
155 
156 	/* Get per-cpu bitmaps */
157 	pcpu_mask = this_cpu_ptr(pcpu_masks);
158 
159 	if (mips_cm_is64)
160 		__ioread64_copy(pending, addr_gic_pend(),
161 				DIV_ROUND_UP(gic_shared_intrs, 64));
162 	else
163 		__ioread32_copy(pending, addr_gic_pend(),
164 				DIV_ROUND_UP(gic_shared_intrs, 32));
165 
166 	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
167 
168 	for_each_set_bit(intr, pending, gic_shared_intrs) {
169 		if (chained)
170 			generic_handle_domain_irq(gic_irq_domain,
171 						  GIC_SHARED_TO_HWIRQ(intr));
172 		else
173 			do_domain_IRQ(gic_irq_domain,
174 				      GIC_SHARED_TO_HWIRQ(intr));
175 	}
176 }
177 
178 static void gic_mask_irq(struct irq_data *d)
179 {
180 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
181 
182 	write_gic_rmask(intr);
183 	gic_clear_pcpu_masks(intr);
184 }
185 
186 static void gic_unmask_irq(struct irq_data *d)
187 {
188 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
189 	unsigned int cpu;
190 
191 	write_gic_smask(intr);
192 
193 	gic_clear_pcpu_masks(intr);
194 	cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
195 	set_bit(intr, per_cpu_ptr(pcpu_masks, cpu));
196 }
197 
198 static void gic_ack_irq(struct irq_data *d)
199 {
200 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
201 
202 	write_gic_wedge(irq);
203 }
204 
205 static int gic_set_type(struct irq_data *d, unsigned int type)
206 {
207 	unsigned int irq, pol, trig, dual;
208 	unsigned long flags;
209 
210 	irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
211 
212 	spin_lock_irqsave(&gic_lock, flags);
213 	switch (type & IRQ_TYPE_SENSE_MASK) {
214 	case IRQ_TYPE_EDGE_FALLING:
215 		pol = GIC_POL_FALLING_EDGE;
216 		trig = GIC_TRIG_EDGE;
217 		dual = GIC_DUAL_SINGLE;
218 		break;
219 	case IRQ_TYPE_EDGE_RISING:
220 		pol = GIC_POL_RISING_EDGE;
221 		trig = GIC_TRIG_EDGE;
222 		dual = GIC_DUAL_SINGLE;
223 		break;
224 	case IRQ_TYPE_EDGE_BOTH:
225 		pol = 0; /* Doesn't matter */
226 		trig = GIC_TRIG_EDGE;
227 		dual = GIC_DUAL_DUAL;
228 		break;
229 	case IRQ_TYPE_LEVEL_LOW:
230 		pol = GIC_POL_ACTIVE_LOW;
231 		trig = GIC_TRIG_LEVEL;
232 		dual = GIC_DUAL_SINGLE;
233 		break;
234 	case IRQ_TYPE_LEVEL_HIGH:
235 	default:
236 		pol = GIC_POL_ACTIVE_HIGH;
237 		trig = GIC_TRIG_LEVEL;
238 		dual = GIC_DUAL_SINGLE;
239 		break;
240 	}
241 
242 	change_gic_pol(irq, pol);
243 	change_gic_trig(irq, trig);
244 	change_gic_dual(irq, dual);
245 
246 	if (trig == GIC_TRIG_EDGE)
247 		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
248 						 handle_edge_irq, NULL);
249 	else
250 		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
251 						 handle_level_irq, NULL);
252 	spin_unlock_irqrestore(&gic_lock, flags);
253 
254 	return 0;
255 }
256 
257 #ifdef CONFIG_SMP
258 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
259 			    bool force)
260 {
261 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
262 	unsigned long flags;
263 	unsigned int cpu;
264 
265 	cpu = cpumask_first_and(cpumask, cpu_online_mask);
266 	if (cpu >= NR_CPUS)
267 		return -EINVAL;
268 
269 	/* Assumption : cpumask refers to a single CPU */
270 	spin_lock_irqsave(&gic_lock, flags);
271 
272 	/* Re-route this IRQ */
273 	write_gic_map_vp(irq, BIT(mips_cm_vp_id(cpu)));
274 
275 	/* Update the pcpu_masks */
276 	gic_clear_pcpu_masks(irq);
277 	if (read_gic_mask(irq))
278 		set_bit(irq, per_cpu_ptr(pcpu_masks, cpu));
279 
280 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
281 	spin_unlock_irqrestore(&gic_lock, flags);
282 
283 	return IRQ_SET_MASK_OK;
284 }
285 #endif
286 
287 static struct irq_chip gic_level_irq_controller = {
288 	.name			=	"MIPS GIC",
289 	.irq_mask		=	gic_mask_irq,
290 	.irq_unmask		=	gic_unmask_irq,
291 	.irq_set_type		=	gic_set_type,
292 #ifdef CONFIG_SMP
293 	.irq_set_affinity	=	gic_set_affinity,
294 #endif
295 };
296 
297 static struct irq_chip gic_edge_irq_controller = {
298 	.name			=	"MIPS GIC",
299 	.irq_ack		=	gic_ack_irq,
300 	.irq_mask		=	gic_mask_irq,
301 	.irq_unmask		=	gic_unmask_irq,
302 	.irq_set_type		=	gic_set_type,
303 #ifdef CONFIG_SMP
304 	.irq_set_affinity	=	gic_set_affinity,
305 #endif
306 	.ipi_send_single	=	gic_send_ipi,
307 };
308 
309 static void gic_handle_local_int(bool chained)
310 {
311 	unsigned long pending, masked;
312 	unsigned int intr;
313 
314 	pending = read_gic_vl_pend();
315 	masked = read_gic_vl_mask();
316 
317 	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);
318 
319 	for_each_set_bit(intr, &pending, GIC_NUM_LOCAL_INTRS) {
320 		if (chained)
321 			generic_handle_domain_irq(gic_irq_domain,
322 						  GIC_LOCAL_TO_HWIRQ(intr));
323 		else
324 			do_domain_IRQ(gic_irq_domain,
325 				      GIC_LOCAL_TO_HWIRQ(intr));
326 	}
327 }
328 
329 static void gic_mask_local_irq(struct irq_data *d)
330 {
331 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
332 
333 	write_gic_vl_rmask(BIT(intr));
334 }
335 
336 static void gic_unmask_local_irq(struct irq_data *d)
337 {
338 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
339 
340 	write_gic_vl_smask(BIT(intr));
341 }
342 
343 static struct irq_chip gic_local_irq_controller = {
344 	.name			=	"MIPS GIC Local",
345 	.irq_mask		=	gic_mask_local_irq,
346 	.irq_unmask		=	gic_unmask_local_irq,
347 };
348 
349 static void gic_mask_local_irq_all_vpes(struct irq_data *d)
350 {
351 	struct gic_all_vpes_chip_data *cd;
352 	unsigned long flags;
353 	int intr, cpu;
354 
355 	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
356 	cd = irq_data_get_irq_chip_data(d);
357 	cd->mask = false;
358 
359 	spin_lock_irqsave(&gic_lock, flags);
360 	for_each_online_cpu(cpu) {
361 		write_gic_vl_other(mips_cm_vp_id(cpu));
362 		write_gic_vo_rmask(BIT(intr));
363 	}
364 	spin_unlock_irqrestore(&gic_lock, flags);
365 }
366 
367 static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
368 {
369 	struct gic_all_vpes_chip_data *cd;
370 	unsigned long flags;
371 	int intr, cpu;
372 
373 	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
374 	cd = irq_data_get_irq_chip_data(d);
375 	cd->mask = true;
376 
377 	spin_lock_irqsave(&gic_lock, flags);
378 	for_each_online_cpu(cpu) {
379 		write_gic_vl_other(mips_cm_vp_id(cpu));
380 		write_gic_vo_smask(BIT(intr));
381 	}
382 	spin_unlock_irqrestore(&gic_lock, flags);
383 }
384 
385 static void gic_all_vpes_irq_cpu_online(void)
386 {
387 	static const unsigned int local_intrs[] = {
388 		GIC_LOCAL_INT_TIMER,
389 		GIC_LOCAL_INT_PERFCTR,
390 		GIC_LOCAL_INT_FDC,
391 	};
392 	unsigned long flags;
393 	int i;
394 
395 	spin_lock_irqsave(&gic_lock, flags);
396 
397 	for (i = 0; i < ARRAY_SIZE(local_intrs); i++) {
398 		unsigned int intr = local_intrs[i];
399 		struct gic_all_vpes_chip_data *cd;
400 
401 		cd = &gic_all_vpes_chip_data[intr];
402 		write_gic_vl_map(mips_gic_vx_map_reg(intr), cd->map);
403 		if (cd->mask)
404 			write_gic_vl_smask(BIT(intr));
405 	}
406 
407 	spin_unlock_irqrestore(&gic_lock, flags);
408 }
409 
410 static struct irq_chip gic_all_vpes_local_irq_controller = {
411 	.name			= "MIPS GIC Local",
412 	.irq_mask		= gic_mask_local_irq_all_vpes,
413 	.irq_unmask		= gic_unmask_local_irq_all_vpes,
414 };
415 
416 static void __gic_irq_dispatch(void)
417 {
418 	gic_handle_local_int(false);
419 	gic_handle_shared_int(false);
420 }
421 
422 static void gic_irq_dispatch(struct irq_desc *desc)
423 {
424 	gic_handle_local_int(true);
425 	gic_handle_shared_int(true);
426 }
427 
428 static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
429 				     irq_hw_number_t hw, unsigned int cpu)
430 {
431 	int intr = GIC_HWIRQ_TO_SHARED(hw);
432 	struct irq_data *data;
433 	unsigned long flags;
434 
435 	data = irq_get_irq_data(virq);
436 
437 	spin_lock_irqsave(&gic_lock, flags);
438 	write_gic_map_pin(intr, GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
439 	write_gic_map_vp(intr, BIT(mips_cm_vp_id(cpu)));
440 	irq_data_update_effective_affinity(data, cpumask_of(cpu));
441 	spin_unlock_irqrestore(&gic_lock, flags);
442 
443 	return 0;
444 }
445 
446 static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
447 				const u32 *intspec, unsigned int intsize,
448 				irq_hw_number_t *out_hwirq,
449 				unsigned int *out_type)
450 {
451 	if (intsize != 3)
452 		return -EINVAL;
453 
454 	if (intspec[0] == GIC_SHARED)
455 		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
456 	else if (intspec[0] == GIC_LOCAL)
457 		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
458 	else
459 		return -EINVAL;
460 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
461 
462 	return 0;
463 }
464 
465 static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
466 			      irq_hw_number_t hwirq)
467 {
468 	struct gic_all_vpes_chip_data *cd;
469 	unsigned long flags;
470 	unsigned int intr;
471 	int err, cpu;
472 	u32 map;
473 
474 	if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
475 		/* verify that shared irqs don't conflict with an IPI irq */
476 		if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv))
477 			return -EBUSY;
478 
479 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
480 						    &gic_level_irq_controller,
481 						    NULL);
482 		if (err)
483 			return err;
484 
485 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
486 		return gic_shared_irq_domain_map(d, virq, hwirq, 0);
487 	}
488 
489 	intr = GIC_HWIRQ_TO_LOCAL(hwirq);
490 	map = GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin;
491 
492 	/*
493 	 * If adding support for more per-cpu interrupts, keep the the
494 	 * array in gic_all_vpes_irq_cpu_online() in sync.
495 	 */
496 	switch (intr) {
497 	case GIC_LOCAL_INT_TIMER:
498 		/* CONFIG_MIPS_CMP workaround (see __gic_init) */
499 		map = GIC_MAP_PIN_MAP_TO_PIN | timer_cpu_pin;
500 		fallthrough;
501 	case GIC_LOCAL_INT_PERFCTR:
502 	case GIC_LOCAL_INT_FDC:
503 		/*
504 		 * HACK: These are all really percpu interrupts, but
505 		 * the rest of the MIPS kernel code does not use the
506 		 * percpu IRQ API for them.
507 		 */
508 		cd = &gic_all_vpes_chip_data[intr];
509 		cd->map = map;
510 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
511 						    &gic_all_vpes_local_irq_controller,
512 						    cd);
513 		if (err)
514 			return err;
515 
516 		irq_set_handler(virq, handle_percpu_irq);
517 		break;
518 
519 	default:
520 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
521 						    &gic_local_irq_controller,
522 						    NULL);
523 		if (err)
524 			return err;
525 
526 		irq_set_handler(virq, handle_percpu_devid_irq);
527 		irq_set_percpu_devid(virq);
528 		break;
529 	}
530 
531 	if (!gic_local_irq_is_routable(intr))
532 		return -EPERM;
533 
534 	spin_lock_irqsave(&gic_lock, flags);
535 	for_each_online_cpu(cpu) {
536 		write_gic_vl_other(mips_cm_vp_id(cpu));
537 		write_gic_vo_map(mips_gic_vx_map_reg(intr), map);
538 	}
539 	spin_unlock_irqrestore(&gic_lock, flags);
540 
541 	return 0;
542 }
543 
544 static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
545 				unsigned int nr_irqs, void *arg)
546 {
547 	struct irq_fwspec *fwspec = arg;
548 	irq_hw_number_t hwirq;
549 
550 	if (fwspec->param[0] == GIC_SHARED)
551 		hwirq = GIC_SHARED_TO_HWIRQ(fwspec->param[1]);
552 	else
553 		hwirq = GIC_LOCAL_TO_HWIRQ(fwspec->param[1]);
554 
555 	return gic_irq_domain_map(d, virq, hwirq);
556 }
557 
558 void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
559 			 unsigned int nr_irqs)
560 {
561 }
562 
563 static const struct irq_domain_ops gic_irq_domain_ops = {
564 	.xlate = gic_irq_domain_xlate,
565 	.alloc = gic_irq_domain_alloc,
566 	.free = gic_irq_domain_free,
567 	.map = gic_irq_domain_map,
568 };
569 
570 static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
571 				const u32 *intspec, unsigned int intsize,
572 				irq_hw_number_t *out_hwirq,
573 				unsigned int *out_type)
574 {
575 	/*
576 	 * There's nothing to translate here. hwirq is dynamically allocated and
577 	 * the irq type is always edge triggered.
578 	 * */
579 	*out_hwirq = 0;
580 	*out_type = IRQ_TYPE_EDGE_RISING;
581 
582 	return 0;
583 }
584 
585 static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
586 				unsigned int nr_irqs, void *arg)
587 {
588 	struct cpumask *ipimask = arg;
589 	irq_hw_number_t hwirq, base_hwirq;
590 	int cpu, ret, i;
591 
592 	base_hwirq = find_first_bit(ipi_available, gic_shared_intrs);
593 	if (base_hwirq == gic_shared_intrs)
594 		return -ENOMEM;
595 
596 	/* check that we have enough space */
597 	for (i = base_hwirq; i < nr_irqs; i++) {
598 		if (!test_bit(i, ipi_available))
599 			return -EBUSY;
600 	}
601 	bitmap_clear(ipi_available, base_hwirq, nr_irqs);
602 
603 	/* map the hwirq for each cpu consecutively */
604 	i = 0;
605 	for_each_cpu(cpu, ipimask) {
606 		hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);
607 
608 		ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
609 						    &gic_edge_irq_controller,
610 						    NULL);
611 		if (ret)
612 			goto error;
613 
614 		ret = irq_domain_set_hwirq_and_chip(d->parent, virq + i, hwirq,
615 						    &gic_edge_irq_controller,
616 						    NULL);
617 		if (ret)
618 			goto error;
619 
620 		ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
621 		if (ret)
622 			goto error;
623 
624 		ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
625 		if (ret)
626 			goto error;
627 
628 		i++;
629 	}
630 
631 	return 0;
632 error:
633 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
634 	return ret;
635 }
636 
637 static void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
638 				unsigned int nr_irqs)
639 {
640 	irq_hw_number_t base_hwirq;
641 	struct irq_data *data;
642 
643 	data = irq_get_irq_data(virq);
644 	if (!data)
645 		return;
646 
647 	base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
648 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
649 }
650 
651 static int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
652 				enum irq_domain_bus_token bus_token)
653 {
654 	bool is_ipi;
655 
656 	switch (bus_token) {
657 	case DOMAIN_BUS_IPI:
658 		is_ipi = d->bus_token == bus_token;
659 		return (!node || to_of_node(d->fwnode) == node) && is_ipi;
660 		break;
661 	default:
662 		return 0;
663 	}
664 }
665 
666 static const struct irq_domain_ops gic_ipi_domain_ops = {
667 	.xlate = gic_ipi_domain_xlate,
668 	.alloc = gic_ipi_domain_alloc,
669 	.free = gic_ipi_domain_free,
670 	.match = gic_ipi_domain_match,
671 };
672 
673 static int gic_cpu_startup(unsigned int cpu)
674 {
675 	/* Enable or disable EIC */
676 	change_gic_vl_ctl(GIC_VX_CTL_EIC,
677 			  cpu_has_veic ? GIC_VX_CTL_EIC : 0);
678 
679 	/* Clear all local IRQ masks (ie. disable all local interrupts) */
680 	write_gic_vl_rmask(~0);
681 
682 	/* Enable desired interrupts */
683 	gic_all_vpes_irq_cpu_online();
684 
685 	return 0;
686 }
687 
688 static int __init gic_of_init(struct device_node *node,
689 			      struct device_node *parent)
690 {
691 	unsigned int cpu_vec, i, gicconfig, v[2], num_ipis;
692 	unsigned long reserved;
693 	phys_addr_t gic_base;
694 	struct resource res;
695 	size_t gic_len;
696 
697 	/* Find the first available CPU vector. */
698 	i = 0;
699 	reserved = (C_SW0 | C_SW1) >> __ffs(C_SW0);
700 	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
701 					   i++, &cpu_vec))
702 		reserved |= BIT(cpu_vec);
703 
704 	cpu_vec = find_first_zero_bit(&reserved, hweight_long(ST0_IM));
705 	if (cpu_vec == hweight_long(ST0_IM)) {
706 		pr_err("No CPU vectors available\n");
707 		return -ENODEV;
708 	}
709 
710 	if (of_address_to_resource(node, 0, &res)) {
711 		/*
712 		 * Probe the CM for the GIC base address if not specified
713 		 * in the device-tree.
714 		 */
715 		if (mips_cm_present()) {
716 			gic_base = read_gcr_gic_base() &
717 				~CM_GCR_GIC_BASE_GICEN;
718 			gic_len = 0x20000;
719 			pr_warn("Using inherited base address %pa\n",
720 				&gic_base);
721 		} else {
722 			pr_err("Failed to get memory range\n");
723 			return -ENODEV;
724 		}
725 	} else {
726 		gic_base = res.start;
727 		gic_len = resource_size(&res);
728 	}
729 
730 	if (mips_cm_present()) {
731 		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN);
732 		/* Ensure GIC region is enabled before trying to access it */
733 		__sync();
734 	}
735 
736 	mips_gic_base = ioremap(gic_base, gic_len);
737 
738 	gicconfig = read_gic_config();
739 	gic_shared_intrs = FIELD_GET(GIC_CONFIG_NUMINTERRUPTS, gicconfig);
740 	gic_shared_intrs = (gic_shared_intrs + 1) * 8;
741 
742 	if (cpu_has_veic) {
743 		/* Always use vector 1 in EIC mode */
744 		gic_cpu_pin = 0;
745 		timer_cpu_pin = gic_cpu_pin;
746 		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
747 			       __gic_irq_dispatch);
748 	} else {
749 		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
750 		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
751 					gic_irq_dispatch);
752 		/*
753 		 * With the CMP implementation of SMP (deprecated), other CPUs
754 		 * are started by the bootloader and put into a timer based
755 		 * waiting poll loop. We must not re-route those CPU's local
756 		 * timer interrupts as the wait instruction will never finish,
757 		 * so just handle whatever CPU interrupt it is routed to by
758 		 * default.
759 		 *
760 		 * This workaround should be removed when CMP support is
761 		 * dropped.
762 		 */
763 		if (IS_ENABLED(CONFIG_MIPS_CMP) &&
764 		    gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER)) {
765 			timer_cpu_pin = read_gic_vl_timer_map() & GIC_MAP_PIN_MAP;
766 			irq_set_chained_handler(MIPS_CPU_IRQ_BASE +
767 						GIC_CPU_PIN_OFFSET +
768 						timer_cpu_pin,
769 						gic_irq_dispatch);
770 		} else {
771 			timer_cpu_pin = gic_cpu_pin;
772 		}
773 	}
774 
775 	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
776 					       gic_shared_intrs, 0,
777 					       &gic_irq_domain_ops, NULL);
778 	if (!gic_irq_domain) {
779 		pr_err("Failed to add IRQ domain");
780 		return -ENXIO;
781 	}
782 
783 	gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain,
784 						  IRQ_DOMAIN_FLAG_IPI_PER_CPU,
785 						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
786 						  node, &gic_ipi_domain_ops, NULL);
787 	if (!gic_ipi_domain) {
788 		pr_err("Failed to add IPI domain");
789 		return -ENXIO;
790 	}
791 
792 	irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);
793 
794 	if (node &&
795 	    !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
796 		bitmap_set(ipi_resrv, v[0], v[1]);
797 	} else {
798 		/*
799 		 * Reserve 2 interrupts per possible CPU/VP for use as IPIs,
800 		 * meeting the requirements of arch/mips SMP.
801 		 */
802 		num_ipis = 2 * num_possible_cpus();
803 		bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis);
804 	}
805 
806 	bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);
807 
808 	board_bind_eic_interrupt = &gic_bind_eic_interrupt;
809 
810 	/* Setup defaults */
811 	for (i = 0; i < gic_shared_intrs; i++) {
812 		change_gic_pol(i, GIC_POL_ACTIVE_HIGH);
813 		change_gic_trig(i, GIC_TRIG_LEVEL);
814 		write_gic_rmask(i);
815 	}
816 
817 	return cpuhp_setup_state(CPUHP_AP_IRQ_MIPS_GIC_STARTING,
818 				 "irqchip/mips/gic:starting",
819 				 gic_cpu_startup, NULL);
820 }
821 IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);
822