xref: /openbmc/linux/drivers/irqchip/irq-mips-gic.c (revision 28efb0046512e8a13ed9f9bdf0d68d10bbfbe9cf)
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 #include <linux/bitmap.h>
10 #include <linux/clocksource.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/irqchip.h>
15 #include <linux/of_address.h>
16 #include <linux/percpu.h>
17 #include <linux/sched.h>
18 #include <linux/smp.h>
19 
20 #include <asm/mips-cps.h>
21 #include <asm/setup.h>
22 #include <asm/traps.h>
23 
24 #include <dt-bindings/interrupt-controller/mips-gic.h>
25 
26 #define GIC_MAX_INTRS		256
27 #define GIC_MAX_LONGS		BITS_TO_LONGS(GIC_MAX_INTRS)
28 
29 /* Add 2 to convert GIC CPU pin to core interrupt */
30 #define GIC_CPU_PIN_OFFSET	2
31 
32 /* Mapped interrupt to pin X, then GIC will generate the vector (X+1). */
33 #define GIC_PIN_TO_VEC_OFFSET	1
34 
35 /* Convert between local/shared IRQ number and GIC HW IRQ number. */
36 #define GIC_LOCAL_HWIRQ_BASE	0
37 #define GIC_LOCAL_TO_HWIRQ(x)	(GIC_LOCAL_HWIRQ_BASE + (x))
38 #define GIC_HWIRQ_TO_LOCAL(x)	((x) - GIC_LOCAL_HWIRQ_BASE)
39 #define GIC_SHARED_HWIRQ_BASE	GIC_NUM_LOCAL_INTRS
40 #define GIC_SHARED_TO_HWIRQ(x)	(GIC_SHARED_HWIRQ_BASE + (x))
41 #define GIC_HWIRQ_TO_SHARED(x)	((x) - GIC_SHARED_HWIRQ_BASE)
42 
43 void __iomem *mips_gic_base;
44 
45 DEFINE_PER_CPU_READ_MOSTLY(unsigned long[GIC_MAX_LONGS], pcpu_masks);
46 
47 static DEFINE_SPINLOCK(gic_lock);
48 static struct irq_domain *gic_irq_domain;
49 static struct irq_domain *gic_ipi_domain;
50 static int gic_shared_intrs;
51 static int gic_vpes;
52 static unsigned int gic_cpu_pin;
53 static unsigned int timer_cpu_pin;
54 static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
55 DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
56 DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS);
57 
58 static void gic_clear_pcpu_masks(unsigned int intr)
59 {
60 	unsigned int i;
61 
62 	/* Clear the interrupt's bit in all pcpu_masks */
63 	for_each_possible_cpu(i)
64 		clear_bit(intr, per_cpu_ptr(pcpu_masks, i));
65 }
66 
67 static bool gic_local_irq_is_routable(int intr)
68 {
69 	u32 vpe_ctl;
70 
71 	/* All local interrupts are routable in EIC mode. */
72 	if (cpu_has_veic)
73 		return true;
74 
75 	vpe_ctl = read_gic_vl_ctl();
76 	switch (intr) {
77 	case GIC_LOCAL_INT_TIMER:
78 		return vpe_ctl & GIC_VX_CTL_TIMER_ROUTABLE;
79 	case GIC_LOCAL_INT_PERFCTR:
80 		return vpe_ctl & GIC_VX_CTL_PERFCNT_ROUTABLE;
81 	case GIC_LOCAL_INT_FDC:
82 		return vpe_ctl & GIC_VX_CTL_FDC_ROUTABLE;
83 	case GIC_LOCAL_INT_SWINT0:
84 	case GIC_LOCAL_INT_SWINT1:
85 		return vpe_ctl & GIC_VX_CTL_SWINT_ROUTABLE;
86 	default:
87 		return true;
88 	}
89 }
90 
91 static void gic_bind_eic_interrupt(int irq, int set)
92 {
93 	/* Convert irq vector # to hw int # */
94 	irq -= GIC_PIN_TO_VEC_OFFSET;
95 
96 	/* Set irq to use shadow set */
97 	write_gic_vl_eic_shadow_set(irq, set);
98 }
99 
100 static void gic_send_ipi(struct irq_data *d, unsigned int cpu)
101 {
102 	irq_hw_number_t hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(d));
103 
104 	write_gic_wedge(GIC_WEDGE_RW | hwirq);
105 }
106 
107 int gic_get_c0_compare_int(void)
108 {
109 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
110 		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
111 	return irq_create_mapping(gic_irq_domain,
112 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
113 }
114 
115 int gic_get_c0_perfcount_int(void)
116 {
117 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
118 		/* Is the performance counter shared with the timer? */
119 		if (cp0_perfcount_irq < 0)
120 			return -1;
121 		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
122 	}
123 	return irq_create_mapping(gic_irq_domain,
124 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
125 }
126 
127 int gic_get_c0_fdc_int(void)
128 {
129 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
130 		/* Is the FDC IRQ even present? */
131 		if (cp0_fdc_irq < 0)
132 			return -1;
133 		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
134 	}
135 
136 	return irq_create_mapping(gic_irq_domain,
137 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
138 }
139 
140 static void gic_handle_shared_int(bool chained)
141 {
142 	unsigned int intr, virq;
143 	unsigned long *pcpu_mask;
144 	DECLARE_BITMAP(pending, GIC_MAX_INTRS);
145 
146 	/* Get per-cpu bitmaps */
147 	pcpu_mask = this_cpu_ptr(pcpu_masks);
148 
149 	if (mips_cm_is64)
150 		__ioread64_copy(pending, addr_gic_pend(),
151 				DIV_ROUND_UP(gic_shared_intrs, 64));
152 	else
153 		__ioread32_copy(pending, addr_gic_pend(),
154 				DIV_ROUND_UP(gic_shared_intrs, 32));
155 
156 	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
157 
158 	for_each_set_bit(intr, pending, gic_shared_intrs) {
159 		virq = irq_linear_revmap(gic_irq_domain,
160 					 GIC_SHARED_TO_HWIRQ(intr));
161 		if (chained)
162 			generic_handle_irq(virq);
163 		else
164 			do_IRQ(virq);
165 	}
166 }
167 
168 static void gic_mask_irq(struct irq_data *d)
169 {
170 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
171 
172 	write_gic_rmask(BIT(intr));
173 	gic_clear_pcpu_masks(intr);
174 }
175 
176 static void gic_unmask_irq(struct irq_data *d)
177 {
178 	struct cpumask *affinity = irq_data_get_affinity_mask(d);
179 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
180 	unsigned int cpu;
181 
182 	write_gic_smask(BIT(intr));
183 
184 	gic_clear_pcpu_masks(intr);
185 	cpu = cpumask_first_and(affinity, cpu_online_mask);
186 	set_bit(intr, per_cpu_ptr(pcpu_masks, cpu));
187 }
188 
189 static void gic_ack_irq(struct irq_data *d)
190 {
191 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
192 
193 	write_gic_wedge(irq);
194 }
195 
196 static int gic_set_type(struct irq_data *d, unsigned int type)
197 {
198 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
199 	unsigned long flags;
200 	bool is_edge;
201 
202 	spin_lock_irqsave(&gic_lock, flags);
203 	switch (type & IRQ_TYPE_SENSE_MASK) {
204 	case IRQ_TYPE_EDGE_FALLING:
205 		change_gic_pol(irq, GIC_POL_FALLING_EDGE);
206 		change_gic_trig(irq, GIC_TRIG_EDGE);
207 		change_gic_dual(irq, GIC_DUAL_SINGLE);
208 		is_edge = true;
209 		break;
210 	case IRQ_TYPE_EDGE_RISING:
211 		change_gic_pol(irq, GIC_POL_RISING_EDGE);
212 		change_gic_trig(irq, GIC_TRIG_EDGE);
213 		change_gic_dual(irq, GIC_DUAL_SINGLE);
214 		is_edge = true;
215 		break;
216 	case IRQ_TYPE_EDGE_BOTH:
217 		/* polarity is irrelevant in this case */
218 		change_gic_trig(irq, GIC_TRIG_EDGE);
219 		change_gic_dual(irq, GIC_DUAL_DUAL);
220 		is_edge = true;
221 		break;
222 	case IRQ_TYPE_LEVEL_LOW:
223 		change_gic_pol(irq, GIC_POL_ACTIVE_LOW);
224 		change_gic_trig(irq, GIC_TRIG_LEVEL);
225 		change_gic_dual(irq, GIC_DUAL_SINGLE);
226 		is_edge = false;
227 		break;
228 	case IRQ_TYPE_LEVEL_HIGH:
229 	default:
230 		change_gic_pol(irq, GIC_POL_ACTIVE_HIGH);
231 		change_gic_trig(irq, GIC_TRIG_LEVEL);
232 		change_gic_dual(irq, GIC_DUAL_SINGLE);
233 		is_edge = false;
234 		break;
235 	}
236 
237 	if (is_edge)
238 		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
239 						 handle_edge_irq, NULL);
240 	else
241 		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
242 						 handle_level_irq, NULL);
243 	spin_unlock_irqrestore(&gic_lock, flags);
244 
245 	return 0;
246 }
247 
248 #ifdef CONFIG_SMP
249 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
250 			    bool force)
251 {
252 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
253 	unsigned long flags;
254 	unsigned int cpu;
255 
256 	cpu = cpumask_first_and(cpumask, cpu_online_mask);
257 	if (cpu >= NR_CPUS)
258 		return -EINVAL;
259 
260 	/* Assumption : cpumask refers to a single CPU */
261 	spin_lock_irqsave(&gic_lock, flags);
262 
263 	/* Re-route this IRQ */
264 	write_gic_map_vp(irq, BIT(mips_cm_vp_id(cpu)));
265 
266 	/* Update the pcpu_masks */
267 	gic_clear_pcpu_masks(irq);
268 	if (read_gic_mask(irq))
269 		set_bit(irq, per_cpu_ptr(pcpu_masks, cpu));
270 
271 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
272 	spin_unlock_irqrestore(&gic_lock, flags);
273 
274 	return IRQ_SET_MASK_OK;
275 }
276 #endif
277 
278 static struct irq_chip gic_level_irq_controller = {
279 	.name			=	"MIPS GIC",
280 	.irq_mask		=	gic_mask_irq,
281 	.irq_unmask		=	gic_unmask_irq,
282 	.irq_set_type		=	gic_set_type,
283 #ifdef CONFIG_SMP
284 	.irq_set_affinity	=	gic_set_affinity,
285 #endif
286 };
287 
288 static struct irq_chip gic_edge_irq_controller = {
289 	.name			=	"MIPS GIC",
290 	.irq_ack		=	gic_ack_irq,
291 	.irq_mask		=	gic_mask_irq,
292 	.irq_unmask		=	gic_unmask_irq,
293 	.irq_set_type		=	gic_set_type,
294 #ifdef CONFIG_SMP
295 	.irq_set_affinity	=	gic_set_affinity,
296 #endif
297 	.ipi_send_single	=	gic_send_ipi,
298 };
299 
300 static void gic_handle_local_int(bool chained)
301 {
302 	unsigned long pending, masked;
303 	unsigned int intr, virq;
304 
305 	pending = read_gic_vl_pend();
306 	masked = read_gic_vl_mask();
307 
308 	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);
309 
310 	for_each_set_bit(intr, &pending, GIC_NUM_LOCAL_INTRS) {
311 		virq = irq_linear_revmap(gic_irq_domain,
312 					 GIC_LOCAL_TO_HWIRQ(intr));
313 		if (chained)
314 			generic_handle_irq(virq);
315 		else
316 			do_IRQ(virq);
317 	}
318 }
319 
320 static void gic_mask_local_irq(struct irq_data *d)
321 {
322 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
323 
324 	write_gic_vl_rmask(BIT(intr));
325 }
326 
327 static void gic_unmask_local_irq(struct irq_data *d)
328 {
329 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
330 
331 	write_gic_vl_smask(BIT(intr));
332 }
333 
334 static struct irq_chip gic_local_irq_controller = {
335 	.name			=	"MIPS GIC Local",
336 	.irq_mask		=	gic_mask_local_irq,
337 	.irq_unmask		=	gic_unmask_local_irq,
338 };
339 
340 static void gic_mask_local_irq_all_vpes(struct irq_data *d)
341 {
342 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
343 	int i;
344 	unsigned long flags;
345 
346 	spin_lock_irqsave(&gic_lock, flags);
347 	for (i = 0; i < gic_vpes; i++) {
348 		write_gic_vl_other(mips_cm_vp_id(i));
349 		write_gic_vo_rmask(BIT(intr));
350 	}
351 	spin_unlock_irqrestore(&gic_lock, flags);
352 }
353 
354 static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
355 {
356 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
357 	int i;
358 	unsigned long flags;
359 
360 	spin_lock_irqsave(&gic_lock, flags);
361 	for (i = 0; i < gic_vpes; i++) {
362 		write_gic_vl_other(mips_cm_vp_id(i));
363 		write_gic_vo_smask(BIT(intr));
364 	}
365 	spin_unlock_irqrestore(&gic_lock, flags);
366 }
367 
368 static struct irq_chip gic_all_vpes_local_irq_controller = {
369 	.name			=	"MIPS GIC Local",
370 	.irq_mask		=	gic_mask_local_irq_all_vpes,
371 	.irq_unmask		=	gic_unmask_local_irq_all_vpes,
372 };
373 
374 static void __gic_irq_dispatch(void)
375 {
376 	gic_handle_local_int(false);
377 	gic_handle_shared_int(false);
378 }
379 
380 static void gic_irq_dispatch(struct irq_desc *desc)
381 {
382 	gic_handle_local_int(true);
383 	gic_handle_shared_int(true);
384 }
385 
386 static int gic_local_irq_domain_map(struct irq_domain *d, unsigned int virq,
387 				    irq_hw_number_t hw)
388 {
389 	int intr = GIC_HWIRQ_TO_LOCAL(hw);
390 	int i;
391 	unsigned long flags;
392 	u32 val;
393 
394 	if (!gic_local_irq_is_routable(intr))
395 		return -EPERM;
396 
397 	if (intr > GIC_LOCAL_INT_FDC) {
398 		pr_err("Invalid local IRQ %d\n", intr);
399 		return -EINVAL;
400 	}
401 
402 	if (intr == GIC_LOCAL_INT_TIMER) {
403 		/* CONFIG_MIPS_CMP workaround (see __gic_init) */
404 		val = GIC_MAP_PIN_MAP_TO_PIN | timer_cpu_pin;
405 	} else {
406 		val = GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin;
407 	}
408 
409 	spin_lock_irqsave(&gic_lock, flags);
410 	for (i = 0; i < gic_vpes; i++) {
411 		write_gic_vl_other(mips_cm_vp_id(i));
412 		write_gic_vo_map(intr, val);
413 	}
414 	spin_unlock_irqrestore(&gic_lock, flags);
415 
416 	return 0;
417 }
418 
419 static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
420 				     irq_hw_number_t hw, unsigned int cpu)
421 {
422 	int intr = GIC_HWIRQ_TO_SHARED(hw);
423 	unsigned long flags;
424 
425 	spin_lock_irqsave(&gic_lock, flags);
426 	write_gic_map_pin(intr, GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
427 	write_gic_map_vp(intr, BIT(mips_cm_vp_id(cpu)));
428 	gic_clear_pcpu_masks(intr);
429 	set_bit(intr, per_cpu_ptr(pcpu_masks, cpu));
430 	spin_unlock_irqrestore(&gic_lock, flags);
431 
432 	return 0;
433 }
434 
435 static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
436 				const u32 *intspec, unsigned int intsize,
437 				irq_hw_number_t *out_hwirq,
438 				unsigned int *out_type)
439 {
440 	if (intsize != 3)
441 		return -EINVAL;
442 
443 	if (intspec[0] == GIC_SHARED)
444 		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
445 	else if (intspec[0] == GIC_LOCAL)
446 		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
447 	else
448 		return -EINVAL;
449 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
450 
451 	return 0;
452 }
453 
454 static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
455 			      irq_hw_number_t hwirq)
456 {
457 	int err;
458 
459 	if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
460 		/* verify that shared irqs don't conflict with an IPI irq */
461 		if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv))
462 			return -EBUSY;
463 
464 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
465 						    &gic_level_irq_controller,
466 						    NULL);
467 		if (err)
468 			return err;
469 
470 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
471 		return gic_shared_irq_domain_map(d, virq, hwirq, 0);
472 	}
473 
474 	switch (GIC_HWIRQ_TO_LOCAL(hwirq)) {
475 	case GIC_LOCAL_INT_TIMER:
476 	case GIC_LOCAL_INT_PERFCTR:
477 	case GIC_LOCAL_INT_FDC:
478 		/*
479 		 * HACK: These are all really percpu interrupts, but
480 		 * the rest of the MIPS kernel code does not use the
481 		 * percpu IRQ API for them.
482 		 */
483 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
484 						    &gic_all_vpes_local_irq_controller,
485 						    NULL);
486 		if (err)
487 			return err;
488 
489 		irq_set_handler(virq, handle_percpu_irq);
490 		break;
491 
492 	default:
493 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
494 						    &gic_local_irq_controller,
495 						    NULL);
496 		if (err)
497 			return err;
498 
499 		irq_set_handler(virq, handle_percpu_devid_irq);
500 		irq_set_percpu_devid(virq);
501 		break;
502 	}
503 
504 	return gic_local_irq_domain_map(d, virq, hwirq);
505 }
506 
507 static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
508 				unsigned int nr_irqs, void *arg)
509 {
510 	struct irq_fwspec *fwspec = arg;
511 	irq_hw_number_t hwirq;
512 
513 	if (fwspec->param[0] == GIC_SHARED)
514 		hwirq = GIC_SHARED_TO_HWIRQ(fwspec->param[1]);
515 	else
516 		hwirq = GIC_LOCAL_TO_HWIRQ(fwspec->param[1]);
517 
518 	return gic_irq_domain_map(d, virq, hwirq);
519 }
520 
521 void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
522 			 unsigned int nr_irqs)
523 {
524 }
525 
526 static const struct irq_domain_ops gic_irq_domain_ops = {
527 	.xlate = gic_irq_domain_xlate,
528 	.alloc = gic_irq_domain_alloc,
529 	.free = gic_irq_domain_free,
530 	.map = gic_irq_domain_map,
531 };
532 
533 static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
534 				const u32 *intspec, unsigned int intsize,
535 				irq_hw_number_t *out_hwirq,
536 				unsigned int *out_type)
537 {
538 	/*
539 	 * There's nothing to translate here. hwirq is dynamically allocated and
540 	 * the irq type is always edge triggered.
541 	 * */
542 	*out_hwirq = 0;
543 	*out_type = IRQ_TYPE_EDGE_RISING;
544 
545 	return 0;
546 }
547 
548 static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
549 				unsigned int nr_irqs, void *arg)
550 {
551 	struct cpumask *ipimask = arg;
552 	irq_hw_number_t hwirq, base_hwirq;
553 	int cpu, ret, i;
554 
555 	base_hwirq = find_first_bit(ipi_available, gic_shared_intrs);
556 	if (base_hwirq == gic_shared_intrs)
557 		return -ENOMEM;
558 
559 	/* check that we have enough space */
560 	for (i = base_hwirq; i < nr_irqs; i++) {
561 		if (!test_bit(i, ipi_available))
562 			return -EBUSY;
563 	}
564 	bitmap_clear(ipi_available, base_hwirq, nr_irqs);
565 
566 	/* map the hwirq for each cpu consecutively */
567 	i = 0;
568 	for_each_cpu(cpu, ipimask) {
569 		hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);
570 
571 		ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
572 						    &gic_edge_irq_controller,
573 						    NULL);
574 		if (ret)
575 			goto error;
576 
577 		ret = irq_domain_set_hwirq_and_chip(d->parent, virq + i, hwirq,
578 						    &gic_edge_irq_controller,
579 						    NULL);
580 		if (ret)
581 			goto error;
582 
583 		ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
584 		if (ret)
585 			goto error;
586 
587 		ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
588 		if (ret)
589 			goto error;
590 
591 		i++;
592 	}
593 
594 	return 0;
595 error:
596 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
597 	return ret;
598 }
599 
600 void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
601 			 unsigned int nr_irqs)
602 {
603 	irq_hw_number_t base_hwirq;
604 	struct irq_data *data;
605 
606 	data = irq_get_irq_data(virq);
607 	if (!data)
608 		return;
609 
610 	base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
611 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
612 }
613 
614 int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
615 			 enum irq_domain_bus_token bus_token)
616 {
617 	bool is_ipi;
618 
619 	switch (bus_token) {
620 	case DOMAIN_BUS_IPI:
621 		is_ipi = d->bus_token == bus_token;
622 		return (!node || to_of_node(d->fwnode) == node) && is_ipi;
623 		break;
624 	default:
625 		return 0;
626 	}
627 }
628 
629 static const struct irq_domain_ops gic_ipi_domain_ops = {
630 	.xlate = gic_ipi_domain_xlate,
631 	.alloc = gic_ipi_domain_alloc,
632 	.free = gic_ipi_domain_free,
633 	.match = gic_ipi_domain_match,
634 };
635 
636 
637 static int __init gic_of_init(struct device_node *node,
638 			      struct device_node *parent)
639 {
640 	unsigned int cpu_vec, i, j, gicconfig, cpu, v[2];
641 	unsigned long reserved;
642 	phys_addr_t gic_base;
643 	struct resource res;
644 	size_t gic_len;
645 
646 	/* Find the first available CPU vector. */
647 	i = 0;
648 	reserved = (C_SW0 | C_SW1) >> __fls(C_SW0);
649 	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
650 					   i++, &cpu_vec))
651 		reserved |= BIT(cpu_vec);
652 
653 	cpu_vec = find_first_zero_bit(&reserved, hweight_long(ST0_IM));
654 	if (cpu_vec == hweight_long(ST0_IM)) {
655 		pr_err("No CPU vectors available for GIC\n");
656 		return -ENODEV;
657 	}
658 
659 	if (of_address_to_resource(node, 0, &res)) {
660 		/*
661 		 * Probe the CM for the GIC base address if not specified
662 		 * in the device-tree.
663 		 */
664 		if (mips_cm_present()) {
665 			gic_base = read_gcr_gic_base() &
666 				~CM_GCR_GIC_BASE_GICEN;
667 			gic_len = 0x20000;
668 		} else {
669 			pr_err("Failed to get GIC memory range\n");
670 			return -ENODEV;
671 		}
672 	} else {
673 		gic_base = res.start;
674 		gic_len = resource_size(&res);
675 	}
676 
677 	if (mips_cm_present()) {
678 		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN);
679 		/* Ensure GIC region is enabled before trying to access it */
680 		__sync();
681 	}
682 
683 	mips_gic_base = ioremap_nocache(gic_base, gic_len);
684 
685 	gicconfig = read_gic_config();
686 	gic_shared_intrs = gicconfig & GIC_CONFIG_NUMINTERRUPTS;
687 	gic_shared_intrs >>= __fls(GIC_CONFIG_NUMINTERRUPTS);
688 	gic_shared_intrs = (gic_shared_intrs + 1) * 8;
689 
690 	gic_vpes = gicconfig & GIC_CONFIG_PVPS;
691 	gic_vpes >>= __fls(GIC_CONFIG_PVPS);
692 	gic_vpes = gic_vpes + 1;
693 
694 	if (cpu_has_veic) {
695 		/* Set EIC mode for all VPEs */
696 		for_each_present_cpu(cpu) {
697 			write_gic_vl_other(mips_cm_vp_id(cpu));
698 			write_gic_vo_ctl(GIC_VX_CTL_EIC);
699 		}
700 
701 		/* Always use vector 1 in EIC mode */
702 		gic_cpu_pin = 0;
703 		timer_cpu_pin = gic_cpu_pin;
704 		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
705 			       __gic_irq_dispatch);
706 	} else {
707 		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
708 		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
709 					gic_irq_dispatch);
710 		/*
711 		 * With the CMP implementation of SMP (deprecated), other CPUs
712 		 * are started by the bootloader and put into a timer based
713 		 * waiting poll loop. We must not re-route those CPU's local
714 		 * timer interrupts as the wait instruction will never finish,
715 		 * so just handle whatever CPU interrupt it is routed to by
716 		 * default.
717 		 *
718 		 * This workaround should be removed when CMP support is
719 		 * dropped.
720 		 */
721 		if (IS_ENABLED(CONFIG_MIPS_CMP) &&
722 		    gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER)) {
723 			timer_cpu_pin = read_gic_vl_timer_map() & GIC_MAP_PIN_MAP;
724 			irq_set_chained_handler(MIPS_CPU_IRQ_BASE +
725 						GIC_CPU_PIN_OFFSET +
726 						timer_cpu_pin,
727 						gic_irq_dispatch);
728 		} else {
729 			timer_cpu_pin = gic_cpu_pin;
730 		}
731 	}
732 
733 	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
734 					       gic_shared_intrs, 0,
735 					       &gic_irq_domain_ops, NULL);
736 	if (!gic_irq_domain) {
737 		pr_err("Failed to add GIC IRQ domain");
738 		return -ENXIO;
739 	}
740 
741 	gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain,
742 						  IRQ_DOMAIN_FLAG_IPI_PER_CPU,
743 						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
744 						  node, &gic_ipi_domain_ops, NULL);
745 	if (!gic_ipi_domain) {
746 		pr_err("Failed to add GIC IPI domain");
747 		return -ENXIO;
748 	}
749 
750 	irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);
751 
752 	if (node &&
753 	    !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
754 		bitmap_set(ipi_resrv, v[0], v[1]);
755 	} else {
756 		/* Make the last 2 * gic_vpes available for IPIs */
757 		bitmap_set(ipi_resrv,
758 			   gic_shared_intrs - 2 * gic_vpes,
759 			   2 * gic_vpes);
760 	}
761 
762 	bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);
763 
764 	board_bind_eic_interrupt = &gic_bind_eic_interrupt;
765 
766 	/* Setup defaults */
767 	for (i = 0; i < gic_shared_intrs; i++) {
768 		change_gic_pol(i, GIC_POL_ACTIVE_HIGH);
769 		change_gic_trig(i, GIC_TRIG_LEVEL);
770 		write_gic_rmask(BIT(i));
771 	}
772 
773 	for (i = 0; i < gic_vpes; i++) {
774 		write_gic_vl_other(mips_cm_vp_id(i));
775 		for (j = 0; j < GIC_NUM_LOCAL_INTRS; j++) {
776 			if (!gic_local_irq_is_routable(j))
777 				continue;
778 			write_gic_vo_rmask(BIT(j));
779 		}
780 	}
781 
782 	return 0;
783 }
784 IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);
785