xref: /openbmc/linux/drivers/irqchip/irq-gic-v3.c (revision 2c684d89)
1 /*
2  * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/cpu.h>
19 #include <linux/cpu_pm.h>
20 #include <linux/delay.h>
21 #include <linux/interrupt.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/percpu.h>
26 #include <linux/slab.h>
27 
28 #include <linux/irqchip.h>
29 #include <linux/irqchip/arm-gic-v3.h>
30 
31 #include <asm/cputype.h>
32 #include <asm/exception.h>
33 #include <asm/smp_plat.h>
34 #include <asm/virt.h>
35 
36 #include "irq-gic-common.h"
37 
38 struct redist_region {
39 	void __iomem		*redist_base;
40 	phys_addr_t		phys_base;
41 };
42 
43 struct gic_chip_data {
44 	void __iomem		*dist_base;
45 	struct redist_region	*redist_regions;
46 	struct rdists		rdists;
47 	struct irq_domain	*domain;
48 	u64			redist_stride;
49 	u32			nr_redist_regions;
50 	unsigned int		irq_nr;
51 };
52 
53 static struct gic_chip_data gic_data __read_mostly;
54 static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
55 
56 #define gic_data_rdist()		(this_cpu_ptr(gic_data.rdists.rdist))
57 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
58 #define gic_data_rdist_sgi_base()	(gic_data_rdist_rd_base() + SZ_64K)
59 
60 /* Our default, arbitrary priority value. Linux only uses one anyway. */
61 #define DEFAULT_PMR_VALUE	0xf0
62 
63 static inline unsigned int gic_irq(struct irq_data *d)
64 {
65 	return d->hwirq;
66 }
67 
68 static inline int gic_irq_in_rdist(struct irq_data *d)
69 {
70 	return gic_irq(d) < 32;
71 }
72 
73 static inline void __iomem *gic_dist_base(struct irq_data *d)
74 {
75 	if (gic_irq_in_rdist(d))	/* SGI+PPI -> SGI_base for this CPU */
76 		return gic_data_rdist_sgi_base();
77 
78 	if (d->hwirq <= 1023)		/* SPI -> dist_base */
79 		return gic_data.dist_base;
80 
81 	return NULL;
82 }
83 
84 static void gic_do_wait_for_rwp(void __iomem *base)
85 {
86 	u32 count = 1000000;	/* 1s! */
87 
88 	while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
89 		count--;
90 		if (!count) {
91 			pr_err_ratelimited("RWP timeout, gone fishing\n");
92 			return;
93 		}
94 		cpu_relax();
95 		udelay(1);
96 	};
97 }
98 
99 /* Wait for completion of a distributor change */
100 static void gic_dist_wait_for_rwp(void)
101 {
102 	gic_do_wait_for_rwp(gic_data.dist_base);
103 }
104 
105 /* Wait for completion of a redistributor change */
106 static void gic_redist_wait_for_rwp(void)
107 {
108 	gic_do_wait_for_rwp(gic_data_rdist_rd_base());
109 }
110 
111 #ifdef CONFIG_ARM64
112 static DEFINE_STATIC_KEY_FALSE(is_cavium_thunderx);
113 
114 static u64 __maybe_unused gic_read_iar(void)
115 {
116 	if (static_branch_unlikely(&is_cavium_thunderx))
117 		return gic_read_iar_cavium_thunderx();
118 	else
119 		return gic_read_iar_common();
120 }
121 #endif
122 
123 static void gic_enable_redist(bool enable)
124 {
125 	void __iomem *rbase;
126 	u32 count = 1000000;	/* 1s! */
127 	u32 val;
128 
129 	rbase = gic_data_rdist_rd_base();
130 
131 	val = readl_relaxed(rbase + GICR_WAKER);
132 	if (enable)
133 		/* Wake up this CPU redistributor */
134 		val &= ~GICR_WAKER_ProcessorSleep;
135 	else
136 		val |= GICR_WAKER_ProcessorSleep;
137 	writel_relaxed(val, rbase + GICR_WAKER);
138 
139 	if (!enable) {		/* Check that GICR_WAKER is writeable */
140 		val = readl_relaxed(rbase + GICR_WAKER);
141 		if (!(val & GICR_WAKER_ProcessorSleep))
142 			return;	/* No PM support in this redistributor */
143 	}
144 
145 	while (count--) {
146 		val = readl_relaxed(rbase + GICR_WAKER);
147 		if (enable ^ (val & GICR_WAKER_ChildrenAsleep))
148 			break;
149 		cpu_relax();
150 		udelay(1);
151 	};
152 	if (!count)
153 		pr_err_ratelimited("redistributor failed to %s...\n",
154 				   enable ? "wakeup" : "sleep");
155 }
156 
157 /*
158  * Routines to disable, enable, EOI and route interrupts
159  */
160 static int gic_peek_irq(struct irq_data *d, u32 offset)
161 {
162 	u32 mask = 1 << (gic_irq(d) % 32);
163 	void __iomem *base;
164 
165 	if (gic_irq_in_rdist(d))
166 		base = gic_data_rdist_sgi_base();
167 	else
168 		base = gic_data.dist_base;
169 
170 	return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
171 }
172 
173 static void gic_poke_irq(struct irq_data *d, u32 offset)
174 {
175 	u32 mask = 1 << (gic_irq(d) % 32);
176 	void (*rwp_wait)(void);
177 	void __iomem *base;
178 
179 	if (gic_irq_in_rdist(d)) {
180 		base = gic_data_rdist_sgi_base();
181 		rwp_wait = gic_redist_wait_for_rwp;
182 	} else {
183 		base = gic_data.dist_base;
184 		rwp_wait = gic_dist_wait_for_rwp;
185 	}
186 
187 	writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
188 	rwp_wait();
189 }
190 
191 static void gic_mask_irq(struct irq_data *d)
192 {
193 	gic_poke_irq(d, GICD_ICENABLER);
194 }
195 
196 static void gic_eoimode1_mask_irq(struct irq_data *d)
197 {
198 	gic_mask_irq(d);
199 	/*
200 	 * When masking a forwarded interrupt, make sure it is
201 	 * deactivated as well.
202 	 *
203 	 * This ensures that an interrupt that is getting
204 	 * disabled/masked will not get "stuck", because there is
205 	 * noone to deactivate it (guest is being terminated).
206 	 */
207 	if (irqd_is_forwarded_to_vcpu(d))
208 		gic_poke_irq(d, GICD_ICACTIVER);
209 }
210 
211 static void gic_unmask_irq(struct irq_data *d)
212 {
213 	gic_poke_irq(d, GICD_ISENABLER);
214 }
215 
216 static int gic_irq_set_irqchip_state(struct irq_data *d,
217 				     enum irqchip_irq_state which, bool val)
218 {
219 	u32 reg;
220 
221 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
222 		return -EINVAL;
223 
224 	switch (which) {
225 	case IRQCHIP_STATE_PENDING:
226 		reg = val ? GICD_ISPENDR : GICD_ICPENDR;
227 		break;
228 
229 	case IRQCHIP_STATE_ACTIVE:
230 		reg = val ? GICD_ISACTIVER : GICD_ICACTIVER;
231 		break;
232 
233 	case IRQCHIP_STATE_MASKED:
234 		reg = val ? GICD_ICENABLER : GICD_ISENABLER;
235 		break;
236 
237 	default:
238 		return -EINVAL;
239 	}
240 
241 	gic_poke_irq(d, reg);
242 	return 0;
243 }
244 
245 static int gic_irq_get_irqchip_state(struct irq_data *d,
246 				     enum irqchip_irq_state which, bool *val)
247 {
248 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
249 		return -EINVAL;
250 
251 	switch (which) {
252 	case IRQCHIP_STATE_PENDING:
253 		*val = gic_peek_irq(d, GICD_ISPENDR);
254 		break;
255 
256 	case IRQCHIP_STATE_ACTIVE:
257 		*val = gic_peek_irq(d, GICD_ISACTIVER);
258 		break;
259 
260 	case IRQCHIP_STATE_MASKED:
261 		*val = !gic_peek_irq(d, GICD_ISENABLER);
262 		break;
263 
264 	default:
265 		return -EINVAL;
266 	}
267 
268 	return 0;
269 }
270 
271 static void gic_eoi_irq(struct irq_data *d)
272 {
273 	gic_write_eoir(gic_irq(d));
274 }
275 
276 static void gic_eoimode1_eoi_irq(struct irq_data *d)
277 {
278 	/*
279 	 * No need to deactivate an LPI, or an interrupt that
280 	 * is is getting forwarded to a vcpu.
281 	 */
282 	if (gic_irq(d) >= 8192 || irqd_is_forwarded_to_vcpu(d))
283 		return;
284 	gic_write_dir(gic_irq(d));
285 }
286 
287 static int gic_set_type(struct irq_data *d, unsigned int type)
288 {
289 	unsigned int irq = gic_irq(d);
290 	void (*rwp_wait)(void);
291 	void __iomem *base;
292 
293 	/* Interrupt configuration for SGIs can't be changed */
294 	if (irq < 16)
295 		return -EINVAL;
296 
297 	/* SPIs have restrictions on the supported types */
298 	if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
299 			 type != IRQ_TYPE_EDGE_RISING)
300 		return -EINVAL;
301 
302 	if (gic_irq_in_rdist(d)) {
303 		base = gic_data_rdist_sgi_base();
304 		rwp_wait = gic_redist_wait_for_rwp;
305 	} else {
306 		base = gic_data.dist_base;
307 		rwp_wait = gic_dist_wait_for_rwp;
308 	}
309 
310 	return gic_configure_irq(irq, type, base, rwp_wait);
311 }
312 
313 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
314 {
315 	if (vcpu)
316 		irqd_set_forwarded_to_vcpu(d);
317 	else
318 		irqd_clr_forwarded_to_vcpu(d);
319 	return 0;
320 }
321 
322 static u64 gic_mpidr_to_affinity(unsigned long mpidr)
323 {
324 	u64 aff;
325 
326 	aff = ((u64)MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
327 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
328 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8  |
329 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
330 
331 	return aff;
332 }
333 
334 static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
335 {
336 	u32 irqnr;
337 
338 	do {
339 		irqnr = gic_read_iar();
340 
341 		if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
342 			int err;
343 
344 			if (static_key_true(&supports_deactivate))
345 				gic_write_eoir(irqnr);
346 
347 			err = handle_domain_irq(gic_data.domain, irqnr, regs);
348 			if (err) {
349 				WARN_ONCE(true, "Unexpected interrupt received!\n");
350 				if (static_key_true(&supports_deactivate)) {
351 					if (irqnr < 8192)
352 						gic_write_dir(irqnr);
353 				} else {
354 					gic_write_eoir(irqnr);
355 				}
356 			}
357 			continue;
358 		}
359 		if (irqnr < 16) {
360 			gic_write_eoir(irqnr);
361 			if (static_key_true(&supports_deactivate))
362 				gic_write_dir(irqnr);
363 #ifdef CONFIG_SMP
364 			handle_IPI(irqnr, regs);
365 #else
366 			WARN_ONCE(true, "Unexpected SGI received!\n");
367 #endif
368 			continue;
369 		}
370 	} while (irqnr != ICC_IAR1_EL1_SPURIOUS);
371 }
372 
373 static void __init gic_dist_init(void)
374 {
375 	unsigned int i;
376 	u64 affinity;
377 	void __iomem *base = gic_data.dist_base;
378 
379 	/* Disable the distributor */
380 	writel_relaxed(0, base + GICD_CTLR);
381 	gic_dist_wait_for_rwp();
382 
383 	gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
384 
385 	/* Enable distributor with ARE, Group1 */
386 	writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
387 		       base + GICD_CTLR);
388 
389 	/*
390 	 * Set all global interrupts to the boot CPU only. ARE must be
391 	 * enabled.
392 	 */
393 	affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
394 	for (i = 32; i < gic_data.irq_nr; i++)
395 		gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
396 }
397 
398 static int gic_populate_rdist(void)
399 {
400 	unsigned long mpidr = cpu_logical_map(smp_processor_id());
401 	u64 typer;
402 	u32 aff;
403 	int i;
404 
405 	/*
406 	 * Convert affinity to a 32bit value that can be matched to
407 	 * GICR_TYPER bits [63:32].
408 	 */
409 	aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
410 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
411 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
412 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
413 
414 	for (i = 0; i < gic_data.nr_redist_regions; i++) {
415 		void __iomem *ptr = gic_data.redist_regions[i].redist_base;
416 		u32 reg;
417 
418 		reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
419 		if (reg != GIC_PIDR2_ARCH_GICv3 &&
420 		    reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
421 			pr_warn("No redistributor present @%p\n", ptr);
422 			break;
423 		}
424 
425 		do {
426 			typer = gic_read_typer(ptr + GICR_TYPER);
427 			if ((typer >> 32) == aff) {
428 				u64 offset = ptr - gic_data.redist_regions[i].redist_base;
429 				gic_data_rdist_rd_base() = ptr;
430 				gic_data_rdist()->phys_base = gic_data.redist_regions[i].phys_base + offset;
431 				pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
432 					smp_processor_id(), mpidr, i,
433 					&gic_data_rdist()->phys_base);
434 				return 0;
435 			}
436 
437 			if (gic_data.redist_stride) {
438 				ptr += gic_data.redist_stride;
439 			} else {
440 				ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
441 				if (typer & GICR_TYPER_VLPIS)
442 					ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
443 			}
444 		} while (!(typer & GICR_TYPER_LAST));
445 	}
446 
447 	/* We couldn't even deal with ourselves... */
448 	WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
449 	     smp_processor_id(), mpidr);
450 	return -ENODEV;
451 }
452 
453 static void gic_cpu_sys_reg_init(void)
454 {
455 	/*
456 	 * Need to check that the SRE bit has actually been set. If
457 	 * not, it means that SRE is disabled at EL2. We're going to
458 	 * die painfully, and there is nothing we can do about it.
459 	 *
460 	 * Kindly inform the luser.
461 	 */
462 	if (!gic_enable_sre())
463 		pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
464 
465 	/* Set priority mask register */
466 	gic_write_pmr(DEFAULT_PMR_VALUE);
467 
468 	if (static_key_true(&supports_deactivate)) {
469 		/* EOI drops priority only (mode 1) */
470 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop);
471 	} else {
472 		/* EOI deactivates interrupt too (mode 0) */
473 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
474 	}
475 
476 	/* ... and let's hit the road... */
477 	gic_write_grpen1(1);
478 }
479 
480 static int gic_dist_supports_lpis(void)
481 {
482 	return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS);
483 }
484 
485 static void gic_cpu_init(void)
486 {
487 	void __iomem *rbase;
488 
489 	/* Register ourselves with the rest of the world */
490 	if (gic_populate_rdist())
491 		return;
492 
493 	gic_enable_redist(true);
494 
495 	rbase = gic_data_rdist_sgi_base();
496 
497 	gic_cpu_config(rbase, gic_redist_wait_for_rwp);
498 
499 	/* Give LPIs a spin */
500 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
501 		its_cpu_init();
502 
503 	/* initialise system registers */
504 	gic_cpu_sys_reg_init();
505 }
506 
507 #ifdef CONFIG_SMP
508 static int gic_secondary_init(struct notifier_block *nfb,
509 			      unsigned long action, void *hcpu)
510 {
511 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
512 		gic_cpu_init();
513 	return NOTIFY_OK;
514 }
515 
516 /*
517  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
518  * priority because the GIC needs to be up before the ARM generic timers.
519  */
520 static struct notifier_block gic_cpu_notifier = {
521 	.notifier_call = gic_secondary_init,
522 	.priority = 100,
523 };
524 
525 static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
526 				   unsigned long cluster_id)
527 {
528 	int cpu = *base_cpu;
529 	unsigned long mpidr = cpu_logical_map(cpu);
530 	u16 tlist = 0;
531 
532 	while (cpu < nr_cpu_ids) {
533 		/*
534 		 * If we ever get a cluster of more than 16 CPUs, just
535 		 * scream and skip that CPU.
536 		 */
537 		if (WARN_ON((mpidr & 0xff) >= 16))
538 			goto out;
539 
540 		tlist |= 1 << (mpidr & 0xf);
541 
542 		cpu = cpumask_next(cpu, mask);
543 		if (cpu >= nr_cpu_ids)
544 			goto out;
545 
546 		mpidr = cpu_logical_map(cpu);
547 
548 		if (cluster_id != (mpidr & ~0xffUL)) {
549 			cpu--;
550 			goto out;
551 		}
552 	}
553 out:
554 	*base_cpu = cpu;
555 	return tlist;
556 }
557 
558 #define MPIDR_TO_SGI_AFFINITY(cluster_id, level) \
559 	(MPIDR_AFFINITY_LEVEL(cluster_id, level) \
560 		<< ICC_SGI1R_AFFINITY_## level ##_SHIFT)
561 
562 static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
563 {
564 	u64 val;
565 
566 	val = (MPIDR_TO_SGI_AFFINITY(cluster_id, 3)	|
567 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 2)	|
568 	       irq << ICC_SGI1R_SGI_ID_SHIFT		|
569 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 1)	|
570 	       tlist << ICC_SGI1R_TARGET_LIST_SHIFT);
571 
572 	pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
573 	gic_write_sgi1r(val);
574 }
575 
576 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
577 {
578 	int cpu;
579 
580 	if (WARN_ON(irq >= 16))
581 		return;
582 
583 	/*
584 	 * Ensure that stores to Normal memory are visible to the
585 	 * other CPUs before issuing the IPI.
586 	 */
587 	smp_wmb();
588 
589 	for_each_cpu(cpu, mask) {
590 		unsigned long cluster_id = cpu_logical_map(cpu) & ~0xffUL;
591 		u16 tlist;
592 
593 		tlist = gic_compute_target_list(&cpu, mask, cluster_id);
594 		gic_send_sgi(cluster_id, tlist, irq);
595 	}
596 
597 	/* Force the above writes to ICC_SGI1R_EL1 to be executed */
598 	isb();
599 }
600 
601 static void gic_smp_init(void)
602 {
603 	set_smp_cross_call(gic_raise_softirq);
604 	register_cpu_notifier(&gic_cpu_notifier);
605 }
606 
607 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
608 			    bool force)
609 {
610 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
611 	void __iomem *reg;
612 	int enabled;
613 	u64 val;
614 
615 	if (gic_irq_in_rdist(d))
616 		return -EINVAL;
617 
618 	/* If interrupt was enabled, disable it first */
619 	enabled = gic_peek_irq(d, GICD_ISENABLER);
620 	if (enabled)
621 		gic_mask_irq(d);
622 
623 	reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
624 	val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
625 
626 	gic_write_irouter(val, reg);
627 
628 	/*
629 	 * If the interrupt was enabled, enabled it again. Otherwise,
630 	 * just wait for the distributor to have digested our changes.
631 	 */
632 	if (enabled)
633 		gic_unmask_irq(d);
634 	else
635 		gic_dist_wait_for_rwp();
636 
637 	return IRQ_SET_MASK_OK;
638 }
639 #else
640 #define gic_set_affinity	NULL
641 #define gic_smp_init()		do { } while(0)
642 #endif
643 
644 #ifdef CONFIG_CPU_PM
645 static int gic_cpu_pm_notifier(struct notifier_block *self,
646 			       unsigned long cmd, void *v)
647 {
648 	if (cmd == CPU_PM_EXIT) {
649 		gic_enable_redist(true);
650 		gic_cpu_sys_reg_init();
651 	} else if (cmd == CPU_PM_ENTER) {
652 		gic_write_grpen1(0);
653 		gic_enable_redist(false);
654 	}
655 	return NOTIFY_OK;
656 }
657 
658 static struct notifier_block gic_cpu_pm_notifier_block = {
659 	.notifier_call = gic_cpu_pm_notifier,
660 };
661 
662 static void gic_cpu_pm_init(void)
663 {
664 	cpu_pm_register_notifier(&gic_cpu_pm_notifier_block);
665 }
666 
667 #else
668 static inline void gic_cpu_pm_init(void) { }
669 #endif /* CONFIG_CPU_PM */
670 
671 static struct irq_chip gic_chip = {
672 	.name			= "GICv3",
673 	.irq_mask		= gic_mask_irq,
674 	.irq_unmask		= gic_unmask_irq,
675 	.irq_eoi		= gic_eoi_irq,
676 	.irq_set_type		= gic_set_type,
677 	.irq_set_affinity	= gic_set_affinity,
678 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
679 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
680 	.flags			= IRQCHIP_SET_TYPE_MASKED,
681 };
682 
683 static struct irq_chip gic_eoimode1_chip = {
684 	.name			= "GICv3",
685 	.irq_mask		= gic_eoimode1_mask_irq,
686 	.irq_unmask		= gic_unmask_irq,
687 	.irq_eoi		= gic_eoimode1_eoi_irq,
688 	.irq_set_type		= gic_set_type,
689 	.irq_set_affinity	= gic_set_affinity,
690 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
691 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
692 	.irq_set_vcpu_affinity	= gic_irq_set_vcpu_affinity,
693 	.flags			= IRQCHIP_SET_TYPE_MASKED,
694 };
695 
696 #define GIC_ID_NR		(1U << gic_data.rdists.id_bits)
697 
698 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
699 			      irq_hw_number_t hw)
700 {
701 	struct irq_chip *chip = &gic_chip;
702 
703 	if (static_key_true(&supports_deactivate))
704 		chip = &gic_eoimode1_chip;
705 
706 	/* SGIs are private to the core kernel */
707 	if (hw < 16)
708 		return -EPERM;
709 	/* Nothing here */
710 	if (hw >= gic_data.irq_nr && hw < 8192)
711 		return -EPERM;
712 	/* Off limits */
713 	if (hw >= GIC_ID_NR)
714 		return -EPERM;
715 
716 	/* PPIs */
717 	if (hw < 32) {
718 		irq_set_percpu_devid(irq);
719 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
720 				    handle_percpu_devid_irq, NULL, NULL);
721 		irq_set_status_flags(irq, IRQ_NOAUTOEN);
722 	}
723 	/* SPIs */
724 	if (hw >= 32 && hw < gic_data.irq_nr) {
725 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
726 				    handle_fasteoi_irq, NULL, NULL);
727 		irq_set_probe(irq);
728 	}
729 	/* LPIs */
730 	if (hw >= 8192 && hw < GIC_ID_NR) {
731 		if (!gic_dist_supports_lpis())
732 			return -EPERM;
733 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
734 				    handle_fasteoi_irq, NULL, NULL);
735 	}
736 
737 	return 0;
738 }
739 
740 static int gic_irq_domain_translate(struct irq_domain *d,
741 				    struct irq_fwspec *fwspec,
742 				    unsigned long *hwirq,
743 				    unsigned int *type)
744 {
745 	if (is_of_node(fwspec->fwnode)) {
746 		if (fwspec->param_count < 3)
747 			return -EINVAL;
748 
749 		switch (fwspec->param[0]) {
750 		case 0:			/* SPI */
751 			*hwirq = fwspec->param[1] + 32;
752 			break;
753 		case 1:			/* PPI */
754 			*hwirq = fwspec->param[1] + 16;
755 			break;
756 		case GIC_IRQ_TYPE_LPI:	/* LPI */
757 			*hwirq = fwspec->param[1];
758 			break;
759 		default:
760 			return -EINVAL;
761 		}
762 
763 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
764 		return 0;
765 	}
766 
767 	return -EINVAL;
768 }
769 
770 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
771 				unsigned int nr_irqs, void *arg)
772 {
773 	int i, ret;
774 	irq_hw_number_t hwirq;
775 	unsigned int type = IRQ_TYPE_NONE;
776 	struct irq_fwspec *fwspec = arg;
777 
778 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
779 	if (ret)
780 		return ret;
781 
782 	for (i = 0; i < nr_irqs; i++)
783 		gic_irq_domain_map(domain, virq + i, hwirq + i);
784 
785 	return 0;
786 }
787 
788 static void gic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
789 				unsigned int nr_irqs)
790 {
791 	int i;
792 
793 	for (i = 0; i < nr_irqs; i++) {
794 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
795 		irq_set_handler(virq + i, NULL);
796 		irq_domain_reset_irq_data(d);
797 	}
798 }
799 
800 static const struct irq_domain_ops gic_irq_domain_ops = {
801 	.translate = gic_irq_domain_translate,
802 	.alloc = gic_irq_domain_alloc,
803 	.free = gic_irq_domain_free,
804 };
805 
806 static void gicv3_enable_quirks(void)
807 {
808 #ifdef CONFIG_ARM64
809 	if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_23154))
810 		static_branch_enable(&is_cavium_thunderx);
811 #endif
812 }
813 
814 static int __init gic_of_init(struct device_node *node, struct device_node *parent)
815 {
816 	void __iomem *dist_base;
817 	struct redist_region *rdist_regs;
818 	u64 redist_stride;
819 	u32 nr_redist_regions;
820 	u32 typer;
821 	u32 reg;
822 	int gic_irqs;
823 	int err;
824 	int i;
825 
826 	dist_base = of_iomap(node, 0);
827 	if (!dist_base) {
828 		pr_err("%s: unable to map gic dist registers\n",
829 			node->full_name);
830 		return -ENXIO;
831 	}
832 
833 	reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
834 	if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4) {
835 		pr_err("%s: no distributor detected, giving up\n",
836 			node->full_name);
837 		err = -ENODEV;
838 		goto out_unmap_dist;
839 	}
840 
841 	if (of_property_read_u32(node, "#redistributor-regions", &nr_redist_regions))
842 		nr_redist_regions = 1;
843 
844 	rdist_regs = kzalloc(sizeof(*rdist_regs) * nr_redist_regions, GFP_KERNEL);
845 	if (!rdist_regs) {
846 		err = -ENOMEM;
847 		goto out_unmap_dist;
848 	}
849 
850 	for (i = 0; i < nr_redist_regions; i++) {
851 		struct resource res;
852 		int ret;
853 
854 		ret = of_address_to_resource(node, 1 + i, &res);
855 		rdist_regs[i].redist_base = of_iomap(node, 1 + i);
856 		if (ret || !rdist_regs[i].redist_base) {
857 			pr_err("%s: couldn't map region %d\n",
858 			       node->full_name, i);
859 			err = -ENODEV;
860 			goto out_unmap_rdist;
861 		}
862 		rdist_regs[i].phys_base = res.start;
863 	}
864 
865 	if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
866 		redist_stride = 0;
867 
868 	if (!is_hyp_mode_available())
869 		static_key_slow_dec(&supports_deactivate);
870 
871 	if (static_key_true(&supports_deactivate))
872 		pr_info("GIC: Using split EOI/Deactivate mode\n");
873 
874 	gic_data.dist_base = dist_base;
875 	gic_data.redist_regions = rdist_regs;
876 	gic_data.nr_redist_regions = nr_redist_regions;
877 	gic_data.redist_stride = redist_stride;
878 
879 	gicv3_enable_quirks();
880 
881 	/*
882 	 * Find out how many interrupts are supported.
883 	 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
884 	 */
885 	typer = readl_relaxed(gic_data.dist_base + GICD_TYPER);
886 	gic_data.rdists.id_bits = GICD_TYPER_ID_BITS(typer);
887 	gic_irqs = GICD_TYPER_IRQS(typer);
888 	if (gic_irqs > 1020)
889 		gic_irqs = 1020;
890 	gic_data.irq_nr = gic_irqs;
891 
892 	gic_data.domain = irq_domain_add_tree(node, &gic_irq_domain_ops,
893 					      &gic_data);
894 	gic_data.rdists.rdist = alloc_percpu(typeof(*gic_data.rdists.rdist));
895 
896 	if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdists.rdist)) {
897 		err = -ENOMEM;
898 		goto out_free;
899 	}
900 
901 	set_handle_irq(gic_handle_irq);
902 
903 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
904 		its_init(node, &gic_data.rdists, gic_data.domain);
905 
906 	gic_smp_init();
907 	gic_dist_init();
908 	gic_cpu_init();
909 	gic_cpu_pm_init();
910 
911 	return 0;
912 
913 out_free:
914 	if (gic_data.domain)
915 		irq_domain_remove(gic_data.domain);
916 	free_percpu(gic_data.rdists.rdist);
917 out_unmap_rdist:
918 	for (i = 0; i < nr_redist_regions; i++)
919 		if (rdist_regs[i].redist_base)
920 			iounmap(rdist_regs[i].redist_base);
921 	kfree(rdist_regs);
922 out_unmap_dist:
923 	iounmap(dist_base);
924 	return err;
925 }
926 
927 IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);
928