xref: /linux/drivers/irqchip/irq-mips-gic.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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_RAW_SPINLOCK(gic_lock);
54 static struct irq_domain *gic_irq_domain;
55 static int gic_shared_intrs;
56 static unsigned int gic_cpu_pin;
57 static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
58 
59 #ifdef CONFIG_GENERIC_IRQ_IPI
60 static DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
61 static DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS);
62 #endif /* CONFIG_GENERIC_IRQ_IPI */
63 
64 static struct gic_all_vpes_chip_data {
65 	u32	map;
66 	bool	mask;
67 } gic_all_vpes_chip_data[GIC_NUM_LOCAL_INTRS];
68 
69 static int __gic_with_next_online_cpu(int prev)
70 {
71 	unsigned int cpu;
72 
73 	/* Discover the next online CPU */
74 	cpu = cpumask_next(prev, cpu_online_mask);
75 
76 	/* If there isn't one, we're done */
77 	if (cpu >= nr_cpu_ids)
78 		return cpu;
79 
80 	/*
81 	 * Move the access lock to the next CPU's GIC local register block.
82 	 *
83 	 * Set GIC_VL_OTHER. Since the caller holds gic_lock nothing can
84 	 * clobber the written value.
85 	 */
86 	write_gic_vl_other(mips_cm_vp_id(cpu));
87 
88 	return cpu;
89 }
90 
91 static inline void gic_unlock_cluster(void)
92 {
93 	if (mips_cps_multicluster_cpus())
94 		mips_cm_unlock_other();
95 }
96 
97 /**
98  * for_each_online_cpu_gic() - Iterate over online CPUs, access local registers
99  * @cpu: An integer variable to hold the current CPU number
100  * @gic_lock: A pointer to raw spin lock used as a guard
101  *
102  * Iterate over online CPUs & configure the other/redirect register region to
103  * access each CPUs GIC local register block, which can be accessed from the
104  * loop body using read_gic_vo_*() or write_gic_vo_*() accessor functions or
105  * their derivatives.
106  */
107 #define for_each_online_cpu_gic(cpu, gic_lock)		\
108 	guard(raw_spinlock_irqsave)(gic_lock);		\
109 	for ((cpu) = __gic_with_next_online_cpu(-1);	\
110 	     (cpu) < nr_cpu_ids;			\
111 	     gic_unlock_cluster(),			\
112 	     (cpu) = __gic_with_next_online_cpu(cpu))
113 
114 /**
115  * gic_irq_lock_cluster() - Lock redirect block access to IRQ's cluster
116  * @d: struct irq_data corresponding to the interrupt we're interested in
117  *
118  * Locks redirect register block access to the global register block of the GIC
119  * within the remote cluster that the IRQ corresponding to @d is affine to,
120  * returning true when this redirect block setup & locking has been performed.
121  *
122  * If @d is affine to the local cluster then no locking is performed and this
123  * function will return false, indicating to the caller that it should access
124  * the local clusters registers without the overhead of indirection through the
125  * redirect block.
126  *
127  * In summary, if this function returns true then the caller should access GIC
128  * registers using redirect register block accessors & then call
129  * mips_cm_unlock_other() when done. If this function returns false then the
130  * caller should trivially access GIC registers in the local cluster.
131  *
132  * Returns true if locking performed, else false.
133  */
134 static bool gic_irq_lock_cluster(struct irq_data *d)
135 {
136 	unsigned int cpu, cl;
137 
138 	cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
139 	BUG_ON(cpu >= NR_CPUS);
140 
141 	cl = cpu_cluster(&cpu_data[cpu]);
142 	if (cl == cpu_cluster(&current_cpu_data))
143 		return false;
144 	if (mips_cps_numcores(cl) == 0)
145 		return false;
146 	mips_cm_lock_other(cl, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL);
147 	return true;
148 }
149 
150 static void gic_clear_pcpu_masks(unsigned int intr)
151 {
152 	unsigned int i;
153 
154 	/* Clear the interrupt's bit in all pcpu_masks */
155 	for_each_possible_cpu(i)
156 		clear_bit(intr, per_cpu_ptr(pcpu_masks, i));
157 }
158 
159 static bool gic_local_irq_is_routable(int intr)
160 {
161 	u32 vpe_ctl;
162 
163 	/* All local interrupts are routable in EIC mode. */
164 	if (cpu_has_veic)
165 		return true;
166 
167 	vpe_ctl = read_gic_vl_ctl();
168 	switch (intr) {
169 	case GIC_LOCAL_INT_TIMER:
170 		return vpe_ctl & GIC_VX_CTL_TIMER_ROUTABLE;
171 	case GIC_LOCAL_INT_PERFCTR:
172 		return vpe_ctl & GIC_VX_CTL_PERFCNT_ROUTABLE;
173 	case GIC_LOCAL_INT_FDC:
174 		return vpe_ctl & GIC_VX_CTL_FDC_ROUTABLE;
175 	case GIC_LOCAL_INT_SWINT0:
176 	case GIC_LOCAL_INT_SWINT1:
177 		return vpe_ctl & GIC_VX_CTL_SWINT_ROUTABLE;
178 	default:
179 		return true;
180 	}
181 }
182 
183 static void gic_bind_eic_interrupt(int irq, int set)
184 {
185 	/* Convert irq vector # to hw int # */
186 	irq -= GIC_PIN_TO_VEC_OFFSET;
187 
188 	/* Set irq to use shadow set */
189 	write_gic_vl_eic_shadow_set(irq, set);
190 }
191 
192 static void gic_send_ipi(struct irq_data *d, unsigned int cpu)
193 {
194 	irq_hw_number_t hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(d));
195 
196 	if (gic_irq_lock_cluster(d)) {
197 		write_gic_redir_wedge(GIC_WEDGE_RW | hwirq);
198 		mips_cm_unlock_other();
199 	} else {
200 		write_gic_wedge(GIC_WEDGE_RW | hwirq);
201 	}
202 }
203 
204 int gic_get_c0_compare_int(void)
205 {
206 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_TIMER))
207 		return MIPS_CPU_IRQ_BASE + cp0_compare_irq;
208 	return irq_create_mapping(gic_irq_domain,
209 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_TIMER));
210 }
211 
212 int gic_get_c0_perfcount_int(void)
213 {
214 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_PERFCTR)) {
215 		/* Is the performance counter shared with the timer? */
216 		if (cp0_perfcount_irq < 0)
217 			return -1;
218 		return MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
219 	}
220 	return irq_create_mapping(gic_irq_domain,
221 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_PERFCTR));
222 }
223 
224 int gic_get_c0_fdc_int(void)
225 {
226 	if (!gic_local_irq_is_routable(GIC_LOCAL_INT_FDC)) {
227 		/* Is the FDC IRQ even present? */
228 		if (cp0_fdc_irq < 0)
229 			return -1;
230 		return MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
231 	}
232 
233 	return irq_create_mapping(gic_irq_domain,
234 				  GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_FDC));
235 }
236 
237 static void gic_handle_shared_int(bool chained)
238 {
239 	unsigned int intr;
240 	unsigned long *pcpu_mask;
241 	DECLARE_BITMAP(pending, GIC_MAX_INTRS);
242 
243 	/* Get per-cpu bitmaps */
244 	pcpu_mask = this_cpu_ptr(pcpu_masks);
245 
246 	if (mips_cm_is64)
247 		__ioread64_copy(pending, addr_gic_pend(),
248 				DIV_ROUND_UP(gic_shared_intrs, 64));
249 	else
250 		__ioread32_copy(pending, addr_gic_pend(),
251 				DIV_ROUND_UP(gic_shared_intrs, 32));
252 
253 	bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
254 
255 	for_each_set_bit(intr, pending, gic_shared_intrs) {
256 		if (chained)
257 			generic_handle_domain_irq(gic_irq_domain,
258 						  GIC_SHARED_TO_HWIRQ(intr));
259 		else
260 			do_domain_IRQ(gic_irq_domain,
261 				      GIC_SHARED_TO_HWIRQ(intr));
262 	}
263 }
264 
265 static void gic_mask_irq(struct irq_data *d)
266 {
267 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
268 
269 	if (gic_irq_lock_cluster(d)) {
270 		write_gic_redir_rmask(intr);
271 		mips_cm_unlock_other();
272 	} else {
273 		write_gic_rmask(intr);
274 	}
275 
276 	gic_clear_pcpu_masks(intr);
277 }
278 
279 static void gic_unmask_irq(struct irq_data *d)
280 {
281 	unsigned int intr = GIC_HWIRQ_TO_SHARED(d->hwirq);
282 	unsigned int cpu;
283 
284 	if (gic_irq_lock_cluster(d)) {
285 		write_gic_redir_smask(intr);
286 		mips_cm_unlock_other();
287 	} else {
288 		write_gic_smask(intr);
289 	}
290 
291 	gic_clear_pcpu_masks(intr);
292 	cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
293 	set_bit(intr, per_cpu_ptr(pcpu_masks, cpu));
294 }
295 
296 static void gic_ack_irq(struct irq_data *d)
297 {
298 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
299 
300 	if (gic_irq_lock_cluster(d)) {
301 		write_gic_redir_wedge(irq);
302 		mips_cm_unlock_other();
303 	} else {
304 		write_gic_wedge(irq);
305 	}
306 }
307 
308 static int gic_set_type(struct irq_data *d, unsigned int type)
309 {
310 	unsigned int irq, pol, trig, dual;
311 	unsigned long flags;
312 
313 	irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
314 
315 	raw_spin_lock_irqsave(&gic_lock, flags);
316 	switch (type & IRQ_TYPE_SENSE_MASK) {
317 	case IRQ_TYPE_EDGE_FALLING:
318 		pol = GIC_POL_FALLING_EDGE;
319 		trig = GIC_TRIG_EDGE;
320 		dual = GIC_DUAL_SINGLE;
321 		break;
322 	case IRQ_TYPE_EDGE_RISING:
323 		pol = GIC_POL_RISING_EDGE;
324 		trig = GIC_TRIG_EDGE;
325 		dual = GIC_DUAL_SINGLE;
326 		break;
327 	case IRQ_TYPE_EDGE_BOTH:
328 		pol = 0; /* Doesn't matter */
329 		trig = GIC_TRIG_EDGE;
330 		dual = GIC_DUAL_DUAL;
331 		break;
332 	case IRQ_TYPE_LEVEL_LOW:
333 		pol = GIC_POL_ACTIVE_LOW;
334 		trig = GIC_TRIG_LEVEL;
335 		dual = GIC_DUAL_SINGLE;
336 		break;
337 	case IRQ_TYPE_LEVEL_HIGH:
338 	default:
339 		pol = GIC_POL_ACTIVE_HIGH;
340 		trig = GIC_TRIG_LEVEL;
341 		dual = GIC_DUAL_SINGLE;
342 		break;
343 	}
344 
345 	if (gic_irq_lock_cluster(d)) {
346 		change_gic_redir_pol(irq, pol);
347 		change_gic_redir_trig(irq, trig);
348 		change_gic_redir_dual(irq, dual);
349 		mips_cm_unlock_other();
350 	} else {
351 		change_gic_pol(irq, pol);
352 		change_gic_trig(irq, trig);
353 		change_gic_dual(irq, dual);
354 	}
355 
356 	if (trig == GIC_TRIG_EDGE)
357 		irq_set_chip_handler_name_locked(d, &gic_edge_irq_controller,
358 						 handle_edge_irq, NULL);
359 	else
360 		irq_set_chip_handler_name_locked(d, &gic_level_irq_controller,
361 						 handle_level_irq, NULL);
362 	raw_spin_unlock_irqrestore(&gic_lock, flags);
363 
364 	return 0;
365 }
366 
367 #ifdef CONFIG_SMP
368 static int gic_set_affinity(struct irq_data *d, const struct cpumask *cpumask,
369 			    bool force)
370 {
371 	unsigned int irq = GIC_HWIRQ_TO_SHARED(d->hwirq);
372 	unsigned int cpu, cl, old_cpu, old_cl;
373 	unsigned long flags;
374 
375 	/*
376 	 * The GIC specifies that we can only route an interrupt to one VP(E),
377 	 * ie. CPU in Linux parlance, at a time. Therefore we always route to
378 	 * the first online CPU in the mask.
379 	 */
380 	cpu = cpumask_first_and(cpumask, cpu_online_mask);
381 	if (cpu >= NR_CPUS)
382 		return -EINVAL;
383 
384 	old_cpu = cpumask_first(irq_data_get_effective_affinity_mask(d));
385 	old_cl = cpu_cluster(&cpu_data[old_cpu]);
386 	cl = cpu_cluster(&cpu_data[cpu]);
387 
388 	raw_spin_lock_irqsave(&gic_lock, flags);
389 
390 	/*
391 	 * If we're moving affinity between clusters, stop routing the
392 	 * interrupt to any VP(E) in the old cluster.
393 	 */
394 	if (cl != old_cl) {
395 		if (gic_irq_lock_cluster(d)) {
396 			write_gic_redir_map_vp(irq, 0);
397 			mips_cm_unlock_other();
398 		} else {
399 			write_gic_map_vp(irq, 0);
400 		}
401 	}
402 
403 	/*
404 	 * Update effective affinity - after this gic_irq_lock_cluster() will
405 	 * begin operating on the new cluster.
406 	 */
407 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
408 
409 	/*
410 	 * If we're moving affinity between clusters, configure the interrupt
411 	 * trigger type in the new cluster.
412 	 */
413 	if (cl != old_cl)
414 		gic_set_type(d, irqd_get_trigger_type(d));
415 
416 	/* Route the interrupt to its new VP(E) */
417 	if (gic_irq_lock_cluster(d)) {
418 		write_gic_redir_map_pin(irq,
419 					GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
420 		write_gic_redir_map_vp(irq, BIT(mips_cm_vp_id(cpu)));
421 
422 		/* Update the pcpu_masks */
423 		gic_clear_pcpu_masks(irq);
424 		if (read_gic_redir_mask(irq))
425 			set_bit(irq, per_cpu_ptr(pcpu_masks, cpu));
426 
427 		mips_cm_unlock_other();
428 	} else {
429 		write_gic_map_pin(irq, GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
430 		write_gic_map_vp(irq, BIT(mips_cm_vp_id(cpu)));
431 
432 		/* Update the pcpu_masks */
433 		gic_clear_pcpu_masks(irq);
434 		if (read_gic_mask(irq))
435 			set_bit(irq, per_cpu_ptr(pcpu_masks, cpu));
436 	}
437 
438 	raw_spin_unlock_irqrestore(&gic_lock, flags);
439 
440 	return IRQ_SET_MASK_OK;
441 }
442 #endif
443 
444 static struct irq_chip gic_level_irq_controller = {
445 	.name			=	"MIPS GIC",
446 	.irq_mask		=	gic_mask_irq,
447 	.irq_unmask		=	gic_unmask_irq,
448 	.irq_set_type		=	gic_set_type,
449 #ifdef CONFIG_SMP
450 	.irq_set_affinity	=	gic_set_affinity,
451 #endif
452 };
453 
454 static struct irq_chip gic_edge_irq_controller = {
455 	.name			=	"MIPS GIC",
456 	.irq_ack		=	gic_ack_irq,
457 	.irq_mask		=	gic_mask_irq,
458 	.irq_unmask		=	gic_unmask_irq,
459 	.irq_set_type		=	gic_set_type,
460 #ifdef CONFIG_SMP
461 	.irq_set_affinity	=	gic_set_affinity,
462 #endif
463 	.ipi_send_single	=	gic_send_ipi,
464 };
465 
466 static void gic_handle_local_int(bool chained)
467 {
468 	unsigned long pending, masked;
469 	unsigned int intr;
470 
471 	pending = read_gic_vl_pend();
472 	masked = read_gic_vl_mask();
473 
474 	bitmap_and(&pending, &pending, &masked, GIC_NUM_LOCAL_INTRS);
475 
476 	for_each_set_bit(intr, &pending, GIC_NUM_LOCAL_INTRS) {
477 		if (chained)
478 			generic_handle_domain_irq(gic_irq_domain,
479 						  GIC_LOCAL_TO_HWIRQ(intr));
480 		else
481 			do_domain_IRQ(gic_irq_domain,
482 				      GIC_LOCAL_TO_HWIRQ(intr));
483 	}
484 }
485 
486 static void gic_mask_local_irq(struct irq_data *d)
487 {
488 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
489 
490 	write_gic_vl_rmask(BIT(intr));
491 }
492 
493 static void gic_unmask_local_irq(struct irq_data *d)
494 {
495 	int intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
496 
497 	write_gic_vl_smask(BIT(intr));
498 }
499 
500 static struct irq_chip gic_local_irq_controller = {
501 	.name			=	"MIPS GIC Local",
502 	.irq_mask		=	gic_mask_local_irq,
503 	.irq_unmask		=	gic_unmask_local_irq,
504 };
505 
506 static void gic_mask_local_irq_all_vpes(struct irq_data *d)
507 {
508 	struct gic_all_vpes_chip_data *cd;
509 	int intr, cpu;
510 
511 	if (!mips_cps_multicluster_cpus())
512 		return;
513 
514 	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
515 	cd = irq_data_get_irq_chip_data(d);
516 	cd->mask = false;
517 
518 	for_each_online_cpu_gic(cpu, &gic_lock)
519 		write_gic_vo_rmask(BIT(intr));
520 }
521 
522 static void gic_unmask_local_irq_all_vpes(struct irq_data *d)
523 {
524 	struct gic_all_vpes_chip_data *cd;
525 	int intr, cpu;
526 
527 	if (!mips_cps_multicluster_cpus())
528 		return;
529 
530 	intr = GIC_HWIRQ_TO_LOCAL(d->hwirq);
531 	cd = irq_data_get_irq_chip_data(d);
532 	cd->mask = true;
533 
534 	for_each_online_cpu_gic(cpu, &gic_lock)
535 		write_gic_vo_smask(BIT(intr));
536 }
537 
538 static void gic_all_vpes_irq_cpu_online(void)
539 {
540 	static const unsigned int local_intrs[] = {
541 		GIC_LOCAL_INT_TIMER,
542 		GIC_LOCAL_INT_PERFCTR,
543 		GIC_LOCAL_INT_FDC,
544 	};
545 	unsigned long flags;
546 	int i;
547 
548 	raw_spin_lock_irqsave(&gic_lock, flags);
549 
550 	for (i = 0; i < ARRAY_SIZE(local_intrs); i++) {
551 		unsigned int intr = local_intrs[i];
552 		struct gic_all_vpes_chip_data *cd;
553 
554 		if (!gic_local_irq_is_routable(intr))
555 			continue;
556 		cd = &gic_all_vpes_chip_data[intr];
557 		write_gic_vl_map(mips_gic_vx_map_reg(intr), cd->map);
558 		if (cd->mask)
559 			write_gic_vl_smask(BIT(intr));
560 	}
561 
562 	raw_spin_unlock_irqrestore(&gic_lock, flags);
563 }
564 
565 static struct irq_chip gic_all_vpes_local_irq_controller = {
566 	.name			= "MIPS GIC Local",
567 	.irq_mask		= gic_mask_local_irq_all_vpes,
568 	.irq_unmask		= gic_unmask_local_irq_all_vpes,
569 };
570 
571 static void __gic_irq_dispatch(void)
572 {
573 	gic_handle_local_int(false);
574 	gic_handle_shared_int(false);
575 }
576 
577 static void gic_irq_dispatch(struct irq_desc *desc)
578 {
579 	gic_handle_local_int(true);
580 	gic_handle_shared_int(true);
581 }
582 
583 static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
584 				     irq_hw_number_t hw, unsigned int cpu)
585 {
586 	int intr = GIC_HWIRQ_TO_SHARED(hw);
587 	struct irq_data *data;
588 	unsigned long flags;
589 
590 	data = irq_get_irq_data(virq);
591 	irq_data_update_effective_affinity(data, cpumask_of(cpu));
592 
593 	raw_spin_lock_irqsave(&gic_lock, flags);
594 
595 	/* Route the interrupt to its VP(E) */
596 	if (gic_irq_lock_cluster(data)) {
597 		write_gic_redir_map_pin(intr,
598 					GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
599 		write_gic_redir_map_vp(intr, BIT(mips_cm_vp_id(cpu)));
600 		mips_cm_unlock_other();
601 	} else {
602 		write_gic_map_pin(intr, GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin);
603 		write_gic_map_vp(intr, BIT(mips_cm_vp_id(cpu)));
604 	}
605 
606 	raw_spin_unlock_irqrestore(&gic_lock, flags);
607 
608 	return 0;
609 }
610 
611 static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
612 				const u32 *intspec, unsigned int intsize,
613 				irq_hw_number_t *out_hwirq,
614 				unsigned int *out_type)
615 {
616 	if (intsize != 3)
617 		return -EINVAL;
618 
619 	if (intspec[0] == GIC_SHARED)
620 		*out_hwirq = GIC_SHARED_TO_HWIRQ(intspec[1]);
621 	else if (intspec[0] == GIC_LOCAL)
622 		*out_hwirq = GIC_LOCAL_TO_HWIRQ(intspec[1]);
623 	else
624 		return -EINVAL;
625 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
626 
627 	return 0;
628 }
629 
630 static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
631 			      irq_hw_number_t hwirq)
632 {
633 	struct gic_all_vpes_chip_data *cd;
634 	unsigned int intr;
635 	int err, cpu;
636 	u32 map;
637 
638 	if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
639 #ifdef CONFIG_GENERIC_IRQ_IPI
640 		/* verify that shared irqs don't conflict with an IPI irq */
641 		if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv))
642 			return -EBUSY;
643 #endif /* CONFIG_GENERIC_IRQ_IPI */
644 
645 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
646 						    &gic_level_irq_controller,
647 						    NULL);
648 		if (err)
649 			return err;
650 
651 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(virq)));
652 		return gic_shared_irq_domain_map(d, virq, hwirq, 0);
653 	}
654 
655 	intr = GIC_HWIRQ_TO_LOCAL(hwirq);
656 	map = GIC_MAP_PIN_MAP_TO_PIN | gic_cpu_pin;
657 
658 	/*
659 	 * If adding support for more per-cpu interrupts, keep the
660 	 * array in gic_all_vpes_irq_cpu_online() in sync.
661 	 */
662 	switch (intr) {
663 	case GIC_LOCAL_INT_TIMER:
664 	case GIC_LOCAL_INT_PERFCTR:
665 	case GIC_LOCAL_INT_FDC:
666 		/*
667 		 * HACK: These are all really percpu interrupts, but
668 		 * the rest of the MIPS kernel code does not use the
669 		 * percpu IRQ API for them.
670 		 */
671 		cd = &gic_all_vpes_chip_data[intr];
672 		cd->map = map;
673 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
674 						    &gic_all_vpes_local_irq_controller,
675 						    cd);
676 		if (err)
677 			return err;
678 
679 		irq_set_handler(virq, handle_percpu_irq);
680 		break;
681 
682 	default:
683 		err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
684 						    &gic_local_irq_controller,
685 						    NULL);
686 		if (err)
687 			return err;
688 
689 		irq_set_handler(virq, handle_percpu_devid_irq);
690 		irq_set_percpu_devid(virq);
691 		break;
692 	}
693 
694 	if (!gic_local_irq_is_routable(intr))
695 		return -EPERM;
696 
697 	if (mips_cps_multicluster_cpus()) {
698 		for_each_online_cpu_gic(cpu, &gic_lock)
699 			write_gic_vo_map(mips_gic_vx_map_reg(intr), map);
700 	}
701 
702 	return 0;
703 }
704 
705 static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
706 				unsigned int nr_irqs, void *arg)
707 {
708 	struct irq_fwspec *fwspec = arg;
709 	irq_hw_number_t hwirq;
710 
711 	if (fwspec->param[0] == GIC_SHARED)
712 		hwirq = GIC_SHARED_TO_HWIRQ(fwspec->param[1]);
713 	else
714 		hwirq = GIC_LOCAL_TO_HWIRQ(fwspec->param[1]);
715 
716 	return gic_irq_domain_map(d, virq, hwirq);
717 }
718 
719 static void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
720 			 unsigned int nr_irqs)
721 {
722 }
723 
724 static const struct irq_domain_ops gic_irq_domain_ops = {
725 	.xlate = gic_irq_domain_xlate,
726 	.alloc = gic_irq_domain_alloc,
727 	.free = gic_irq_domain_free,
728 	.map = gic_irq_domain_map,
729 };
730 
731 #ifdef CONFIG_GENERIC_IRQ_IPI
732 
733 static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
734 				const u32 *intspec, unsigned int intsize,
735 				irq_hw_number_t *out_hwirq,
736 				unsigned int *out_type)
737 {
738 	/*
739 	 * There's nothing to translate here. hwirq is dynamically allocated and
740 	 * the irq type is always edge triggered.
741 	 * */
742 	*out_hwirq = 0;
743 	*out_type = IRQ_TYPE_EDGE_RISING;
744 
745 	return 0;
746 }
747 
748 static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
749 				unsigned int nr_irqs, void *arg)
750 {
751 	struct cpumask *ipimask = arg;
752 	irq_hw_number_t hwirq, base_hwirq;
753 	int cpu, ret, i;
754 
755 	base_hwirq = find_first_bit(ipi_available, gic_shared_intrs);
756 	if (base_hwirq == gic_shared_intrs)
757 		return -ENOMEM;
758 
759 	/* check that we have enough space */
760 	for (i = base_hwirq; i < nr_irqs; i++) {
761 		if (!test_bit(i, ipi_available))
762 			return -EBUSY;
763 	}
764 	bitmap_clear(ipi_available, base_hwirq, nr_irqs);
765 
766 	/* map the hwirq for each cpu consecutively */
767 	i = 0;
768 	for_each_cpu(cpu, ipimask) {
769 		hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);
770 
771 		ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
772 						    &gic_edge_irq_controller,
773 						    NULL);
774 		if (ret)
775 			goto error;
776 
777 		ret = irq_domain_set_hwirq_and_chip(d->parent, virq + i, hwirq,
778 						    &gic_edge_irq_controller,
779 						    NULL);
780 		if (ret)
781 			goto error;
782 
783 		/* Set affinity to cpu.  */
784 		irq_data_update_effective_affinity(irq_get_irq_data(virq + i),
785 						   cpumask_of(cpu));
786 		ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
787 		if (ret)
788 			goto error;
789 
790 		ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
791 		if (ret)
792 			goto error;
793 
794 		i++;
795 	}
796 
797 	return 0;
798 error:
799 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
800 	return ret;
801 }
802 
803 static void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
804 				unsigned int nr_irqs)
805 {
806 	irq_hw_number_t base_hwirq;
807 	struct irq_data *data;
808 
809 	data = irq_get_irq_data(virq);
810 	if (!data)
811 		return;
812 
813 	base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
814 	bitmap_set(ipi_available, base_hwirq, nr_irqs);
815 }
816 
817 static int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
818 				enum irq_domain_bus_token bus_token)
819 {
820 	bool is_ipi;
821 
822 	switch (bus_token) {
823 	case DOMAIN_BUS_IPI:
824 		is_ipi = d->bus_token == bus_token;
825 		return (!node || to_of_node(d->fwnode) == node) && is_ipi;
826 		break;
827 	default:
828 		return 0;
829 	}
830 }
831 
832 static const struct irq_domain_ops gic_ipi_domain_ops = {
833 	.xlate = gic_ipi_domain_xlate,
834 	.alloc = gic_ipi_domain_alloc,
835 	.free = gic_ipi_domain_free,
836 	.match = gic_ipi_domain_match,
837 };
838 
839 static int gic_register_ipi_domain(struct device_node *node)
840 {
841 	struct irq_domain *gic_ipi_domain;
842 	unsigned int v[2], num_ipis;
843 
844 	gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain,
845 						  IRQ_DOMAIN_FLAG_IPI_PER_CPU,
846 						  GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
847 						  node, &gic_ipi_domain_ops, NULL);
848 	if (!gic_ipi_domain) {
849 		pr_err("Failed to add IPI domain");
850 		return -ENXIO;
851 	}
852 
853 	irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);
854 
855 	if (node &&
856 	    !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
857 		bitmap_set(ipi_resrv, v[0], v[1]);
858 	} else {
859 		/*
860 		 * Reserve 2 interrupts per possible CPU/VP for use as IPIs,
861 		 * meeting the requirements of arch/mips SMP.
862 		 */
863 		num_ipis = 2 * num_possible_cpus();
864 		bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis);
865 	}
866 
867 	bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);
868 
869 	return 0;
870 }
871 
872 #else /* !CONFIG_GENERIC_IRQ_IPI */
873 
874 static inline int gic_register_ipi_domain(struct device_node *node)
875 {
876 	return 0;
877 }
878 
879 #endif /* !CONFIG_GENERIC_IRQ_IPI */
880 
881 static int gic_cpu_startup(unsigned int cpu)
882 {
883 	/* Enable or disable EIC */
884 	change_gic_vl_ctl(GIC_VX_CTL_EIC,
885 			  cpu_has_veic ? GIC_VX_CTL_EIC : 0);
886 
887 	/* Clear all local IRQ masks (ie. disable all local interrupts) */
888 	write_gic_vl_rmask(~0);
889 
890 	/* Enable desired interrupts */
891 	gic_all_vpes_irq_cpu_online();
892 
893 	return 0;
894 }
895 
896 static int __init gic_of_init(struct device_node *node,
897 			      struct device_node *parent)
898 {
899 	unsigned int cpu_vec, i, gicconfig, cl, nclusters;
900 	unsigned long reserved;
901 	phys_addr_t gic_base;
902 	struct resource res;
903 	size_t gic_len;
904 	int ret;
905 
906 	/* Find the first available CPU vector. */
907 	i = 0;
908 	reserved = (C_SW0 | C_SW1) >> __ffs(C_SW0);
909 	while (!of_property_read_u32_index(node, "mti,reserved-cpu-vectors",
910 					   i++, &cpu_vec))
911 		reserved |= BIT(cpu_vec);
912 
913 	cpu_vec = find_first_zero_bit(&reserved, hweight_long(ST0_IM));
914 	if (cpu_vec == hweight_long(ST0_IM)) {
915 		pr_err("No CPU vectors available\n");
916 		return -ENODEV;
917 	}
918 
919 	if (of_address_to_resource(node, 0, &res)) {
920 		/*
921 		 * Probe the CM for the GIC base address if not specified
922 		 * in the device-tree.
923 		 */
924 		if (mips_cm_present()) {
925 			gic_base = read_gcr_gic_base() &
926 				~CM_GCR_GIC_BASE_GICEN;
927 			gic_len = 0x20000;
928 			pr_warn("Using inherited base address %pa\n",
929 				&gic_base);
930 		} else {
931 			pr_err("Failed to get memory range\n");
932 			return -ENODEV;
933 		}
934 	} else {
935 		gic_base = res.start;
936 		gic_len = resource_size(&res);
937 	}
938 
939 	if (mips_cm_present()) {
940 		write_gcr_gic_base(gic_base | CM_GCR_GIC_BASE_GICEN);
941 		/* Ensure GIC region is enabled before trying to access it */
942 		__sync();
943 	}
944 
945 	mips_gic_base = ioremap(gic_base, gic_len);
946 	if (!mips_gic_base) {
947 		pr_err("Failed to ioremap gic_base\n");
948 		return -ENOMEM;
949 	}
950 
951 	gicconfig = read_gic_config();
952 	gic_shared_intrs = FIELD_GET(GIC_CONFIG_NUMINTERRUPTS, gicconfig);
953 	gic_shared_intrs = (gic_shared_intrs + 1) * 8;
954 
955 	if (cpu_has_veic) {
956 		/* Always use vector 1 in EIC mode */
957 		gic_cpu_pin = 0;
958 		set_vi_handler(gic_cpu_pin + GIC_PIN_TO_VEC_OFFSET,
959 			       __gic_irq_dispatch);
960 	} else {
961 		gic_cpu_pin = cpu_vec - GIC_CPU_PIN_OFFSET;
962 		irq_set_chained_handler(MIPS_CPU_IRQ_BASE + cpu_vec,
963 					gic_irq_dispatch);
964 	}
965 
966 	gic_irq_domain = irq_domain_add_simple(node, GIC_NUM_LOCAL_INTRS +
967 					       gic_shared_intrs, 0,
968 					       &gic_irq_domain_ops, NULL);
969 	if (!gic_irq_domain) {
970 		pr_err("Failed to add IRQ domain");
971 		return -ENXIO;
972 	}
973 
974 	ret = gic_register_ipi_domain(node);
975 	if (ret)
976 		return ret;
977 
978 	board_bind_eic_interrupt = &gic_bind_eic_interrupt;
979 
980 	/*
981 	 * Initialise each cluster's GIC shared registers to sane default
982 	 * values.
983 	 * Otherwise, the IPI set up will be erased if we move code
984 	 * to gic_cpu_startup for each cpu.
985 	 */
986 	nclusters = mips_cps_numclusters();
987 	for (cl = 0; cl < nclusters; cl++) {
988 		if (cl == cpu_cluster(&current_cpu_data)) {
989 			for (i = 0; i < gic_shared_intrs; i++) {
990 				change_gic_pol(i, GIC_POL_ACTIVE_HIGH);
991 				change_gic_trig(i, GIC_TRIG_LEVEL);
992 				write_gic_rmask(i);
993 			}
994 		} else if (mips_cps_numcores(cl) != 0) {
995 			mips_cm_lock_other(cl, 0, 0, CM_GCR_Cx_OTHER_BLOCK_GLOBAL);
996 			for (i = 0; i < gic_shared_intrs; i++) {
997 				change_gic_redir_pol(i, GIC_POL_ACTIVE_HIGH);
998 				change_gic_redir_trig(i, GIC_TRIG_LEVEL);
999 				write_gic_redir_rmask(i);
1000 			}
1001 			mips_cm_unlock_other();
1002 
1003 		} else {
1004 			pr_warn("No CPU cores on the cluster %d skip it\n", cl);
1005 		}
1006 	}
1007 
1008 	return cpuhp_setup_state(CPUHP_AP_IRQ_MIPS_GIC_STARTING,
1009 				 "irqchip/mips/gic:starting",
1010 				 gic_cpu_startup, NULL);
1011 }
1012 IRQCHIP_DECLARE(mips_gic, "mti,gic", gic_of_init);
1013