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