xref: /openbmc/linux/drivers/irqchip/irq-gic-v3.c (revision 3e26a691)
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/acpi.h>
19 #include <linux/cpu.h>
20 #include <linux/cpu_pm.h>
21 #include <linux/delay.h>
22 #include <linux/interrupt.h>
23 #include <linux/irqdomain.h>
24 #include <linux/of.h>
25 #include <linux/of_address.h>
26 #include <linux/of_irq.h>
27 #include <linux/percpu.h>
28 #include <linux/slab.h>
29 
30 #include <linux/irqchip.h>
31 #include <linux/irqchip/arm-gic-v3.h>
32 
33 #include <asm/cputype.h>
34 #include <asm/exception.h>
35 #include <asm/smp_plat.h>
36 #include <asm/virt.h>
37 
38 #include "irq-gic-common.h"
39 
40 struct redist_region {
41 	void __iomem		*redist_base;
42 	phys_addr_t		phys_base;
43 	bool			single_redist;
44 };
45 
46 struct gic_chip_data {
47 	void __iomem		*dist_base;
48 	struct redist_region	*redist_regions;
49 	struct rdists		rdists;
50 	struct irq_domain	*domain;
51 	u64			redist_stride;
52 	u32			nr_redist_regions;
53 	unsigned int		irq_nr;
54 };
55 
56 static struct gic_chip_data gic_data __read_mostly;
57 static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
58 
59 #define gic_data_rdist()		(this_cpu_ptr(gic_data.rdists.rdist))
60 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
61 #define gic_data_rdist_sgi_base()	(gic_data_rdist_rd_base() + SZ_64K)
62 
63 /* Our default, arbitrary priority value. Linux only uses one anyway. */
64 #define DEFAULT_PMR_VALUE	0xf0
65 
66 static inline unsigned int gic_irq(struct irq_data *d)
67 {
68 	return d->hwirq;
69 }
70 
71 static inline int gic_irq_in_rdist(struct irq_data *d)
72 {
73 	return gic_irq(d) < 32;
74 }
75 
76 static inline void __iomem *gic_dist_base(struct irq_data *d)
77 {
78 	if (gic_irq_in_rdist(d))	/* SGI+PPI -> SGI_base for this CPU */
79 		return gic_data_rdist_sgi_base();
80 
81 	if (d->hwirq <= 1023)		/* SPI -> dist_base */
82 		return gic_data.dist_base;
83 
84 	return NULL;
85 }
86 
87 static void gic_do_wait_for_rwp(void __iomem *base)
88 {
89 	u32 count = 1000000;	/* 1s! */
90 
91 	while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
92 		count--;
93 		if (!count) {
94 			pr_err_ratelimited("RWP timeout, gone fishing\n");
95 			return;
96 		}
97 		cpu_relax();
98 		udelay(1);
99 	};
100 }
101 
102 /* Wait for completion of a distributor change */
103 static void gic_dist_wait_for_rwp(void)
104 {
105 	gic_do_wait_for_rwp(gic_data.dist_base);
106 }
107 
108 /* Wait for completion of a redistributor change */
109 static void gic_redist_wait_for_rwp(void)
110 {
111 	gic_do_wait_for_rwp(gic_data_rdist_rd_base());
112 }
113 
114 #ifdef CONFIG_ARM64
115 static DEFINE_STATIC_KEY_FALSE(is_cavium_thunderx);
116 
117 static u64 __maybe_unused gic_read_iar(void)
118 {
119 	if (static_branch_unlikely(&is_cavium_thunderx))
120 		return gic_read_iar_cavium_thunderx();
121 	else
122 		return gic_read_iar_common();
123 }
124 #endif
125 
126 static void gic_enable_redist(bool enable)
127 {
128 	void __iomem *rbase;
129 	u32 count = 1000000;	/* 1s! */
130 	u32 val;
131 
132 	rbase = gic_data_rdist_rd_base();
133 
134 	val = readl_relaxed(rbase + GICR_WAKER);
135 	if (enable)
136 		/* Wake up this CPU redistributor */
137 		val &= ~GICR_WAKER_ProcessorSleep;
138 	else
139 		val |= GICR_WAKER_ProcessorSleep;
140 	writel_relaxed(val, rbase + GICR_WAKER);
141 
142 	if (!enable) {		/* Check that GICR_WAKER is writeable */
143 		val = readl_relaxed(rbase + GICR_WAKER);
144 		if (!(val & GICR_WAKER_ProcessorSleep))
145 			return;	/* No PM support in this redistributor */
146 	}
147 
148 	while (count--) {
149 		val = readl_relaxed(rbase + GICR_WAKER);
150 		if (enable ^ (val & GICR_WAKER_ChildrenAsleep))
151 			break;
152 		cpu_relax();
153 		udelay(1);
154 	};
155 	if (!count)
156 		pr_err_ratelimited("redistributor failed to %s...\n",
157 				   enable ? "wakeup" : "sleep");
158 }
159 
160 /*
161  * Routines to disable, enable, EOI and route interrupts
162  */
163 static int gic_peek_irq(struct irq_data *d, u32 offset)
164 {
165 	u32 mask = 1 << (gic_irq(d) % 32);
166 	void __iomem *base;
167 
168 	if (gic_irq_in_rdist(d))
169 		base = gic_data_rdist_sgi_base();
170 	else
171 		base = gic_data.dist_base;
172 
173 	return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
174 }
175 
176 static void gic_poke_irq(struct irq_data *d, u32 offset)
177 {
178 	u32 mask = 1 << (gic_irq(d) % 32);
179 	void (*rwp_wait)(void);
180 	void __iomem *base;
181 
182 	if (gic_irq_in_rdist(d)) {
183 		base = gic_data_rdist_sgi_base();
184 		rwp_wait = gic_redist_wait_for_rwp;
185 	} else {
186 		base = gic_data.dist_base;
187 		rwp_wait = gic_dist_wait_for_rwp;
188 	}
189 
190 	writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
191 	rwp_wait();
192 }
193 
194 static void gic_mask_irq(struct irq_data *d)
195 {
196 	gic_poke_irq(d, GICD_ICENABLER);
197 }
198 
199 static void gic_eoimode1_mask_irq(struct irq_data *d)
200 {
201 	gic_mask_irq(d);
202 	/*
203 	 * When masking a forwarded interrupt, make sure it is
204 	 * deactivated as well.
205 	 *
206 	 * This ensures that an interrupt that is getting
207 	 * disabled/masked will not get "stuck", because there is
208 	 * noone to deactivate it (guest is being terminated).
209 	 */
210 	if (irqd_is_forwarded_to_vcpu(d))
211 		gic_poke_irq(d, GICD_ICACTIVER);
212 }
213 
214 static void gic_unmask_irq(struct irq_data *d)
215 {
216 	gic_poke_irq(d, GICD_ISENABLER);
217 }
218 
219 static int gic_irq_set_irqchip_state(struct irq_data *d,
220 				     enum irqchip_irq_state which, bool val)
221 {
222 	u32 reg;
223 
224 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
225 		return -EINVAL;
226 
227 	switch (which) {
228 	case IRQCHIP_STATE_PENDING:
229 		reg = val ? GICD_ISPENDR : GICD_ICPENDR;
230 		break;
231 
232 	case IRQCHIP_STATE_ACTIVE:
233 		reg = val ? GICD_ISACTIVER : GICD_ICACTIVER;
234 		break;
235 
236 	case IRQCHIP_STATE_MASKED:
237 		reg = val ? GICD_ICENABLER : GICD_ISENABLER;
238 		break;
239 
240 	default:
241 		return -EINVAL;
242 	}
243 
244 	gic_poke_irq(d, reg);
245 	return 0;
246 }
247 
248 static int gic_irq_get_irqchip_state(struct irq_data *d,
249 				     enum irqchip_irq_state which, bool *val)
250 {
251 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
252 		return -EINVAL;
253 
254 	switch (which) {
255 	case IRQCHIP_STATE_PENDING:
256 		*val = gic_peek_irq(d, GICD_ISPENDR);
257 		break;
258 
259 	case IRQCHIP_STATE_ACTIVE:
260 		*val = gic_peek_irq(d, GICD_ISACTIVER);
261 		break;
262 
263 	case IRQCHIP_STATE_MASKED:
264 		*val = !gic_peek_irq(d, GICD_ISENABLER);
265 		break;
266 
267 	default:
268 		return -EINVAL;
269 	}
270 
271 	return 0;
272 }
273 
274 static void gic_eoi_irq(struct irq_data *d)
275 {
276 	gic_write_eoir(gic_irq(d));
277 }
278 
279 static void gic_eoimode1_eoi_irq(struct irq_data *d)
280 {
281 	/*
282 	 * No need to deactivate an LPI, or an interrupt that
283 	 * is is getting forwarded to a vcpu.
284 	 */
285 	if (gic_irq(d) >= 8192 || irqd_is_forwarded_to_vcpu(d))
286 		return;
287 	gic_write_dir(gic_irq(d));
288 }
289 
290 static int gic_set_type(struct irq_data *d, unsigned int type)
291 {
292 	unsigned int irq = gic_irq(d);
293 	void (*rwp_wait)(void);
294 	void __iomem *base;
295 
296 	/* Interrupt configuration for SGIs can't be changed */
297 	if (irq < 16)
298 		return -EINVAL;
299 
300 	/* SPIs have restrictions on the supported types */
301 	if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
302 			 type != IRQ_TYPE_EDGE_RISING)
303 		return -EINVAL;
304 
305 	if (gic_irq_in_rdist(d)) {
306 		base = gic_data_rdist_sgi_base();
307 		rwp_wait = gic_redist_wait_for_rwp;
308 	} else {
309 		base = gic_data.dist_base;
310 		rwp_wait = gic_dist_wait_for_rwp;
311 	}
312 
313 	return gic_configure_irq(irq, type, base, rwp_wait);
314 }
315 
316 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
317 {
318 	if (vcpu)
319 		irqd_set_forwarded_to_vcpu(d);
320 	else
321 		irqd_clr_forwarded_to_vcpu(d);
322 	return 0;
323 }
324 
325 static u64 gic_mpidr_to_affinity(unsigned long mpidr)
326 {
327 	u64 aff;
328 
329 	aff = ((u64)MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
330 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
331 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8  |
332 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
333 
334 	return aff;
335 }
336 
337 static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
338 {
339 	u32 irqnr;
340 
341 	do {
342 		irqnr = gic_read_iar();
343 
344 		if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
345 			int err;
346 
347 			if (static_key_true(&supports_deactivate))
348 				gic_write_eoir(irqnr);
349 
350 			err = handle_domain_irq(gic_data.domain, irqnr, regs);
351 			if (err) {
352 				WARN_ONCE(true, "Unexpected interrupt received!\n");
353 				if (static_key_true(&supports_deactivate)) {
354 					if (irqnr < 8192)
355 						gic_write_dir(irqnr);
356 				} else {
357 					gic_write_eoir(irqnr);
358 				}
359 			}
360 			continue;
361 		}
362 		if (irqnr < 16) {
363 			gic_write_eoir(irqnr);
364 			if (static_key_true(&supports_deactivate))
365 				gic_write_dir(irqnr);
366 #ifdef CONFIG_SMP
367 			handle_IPI(irqnr, regs);
368 #else
369 			WARN_ONCE(true, "Unexpected SGI received!\n");
370 #endif
371 			continue;
372 		}
373 	} while (irqnr != ICC_IAR1_EL1_SPURIOUS);
374 }
375 
376 static void __init gic_dist_init(void)
377 {
378 	unsigned int i;
379 	u64 affinity;
380 	void __iomem *base = gic_data.dist_base;
381 
382 	/* Disable the distributor */
383 	writel_relaxed(0, base + GICD_CTLR);
384 	gic_dist_wait_for_rwp();
385 
386 	gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
387 
388 	/* Enable distributor with ARE, Group1 */
389 	writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
390 		       base + GICD_CTLR);
391 
392 	/*
393 	 * Set all global interrupts to the boot CPU only. ARE must be
394 	 * enabled.
395 	 */
396 	affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
397 	for (i = 32; i < gic_data.irq_nr; i++)
398 		gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
399 }
400 
401 static int gic_populate_rdist(void)
402 {
403 	unsigned long mpidr = cpu_logical_map(smp_processor_id());
404 	u64 typer;
405 	u32 aff;
406 	int i;
407 
408 	/*
409 	 * Convert affinity to a 32bit value that can be matched to
410 	 * GICR_TYPER bits [63:32].
411 	 */
412 	aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
413 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
414 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
415 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
416 
417 	for (i = 0; i < gic_data.nr_redist_regions; i++) {
418 		void __iomem *ptr = gic_data.redist_regions[i].redist_base;
419 		u32 reg;
420 
421 		reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
422 		if (reg != GIC_PIDR2_ARCH_GICv3 &&
423 		    reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
424 			pr_warn("No redistributor present @%p\n", ptr);
425 			break;
426 		}
427 
428 		do {
429 			typer = gic_read_typer(ptr + GICR_TYPER);
430 			if ((typer >> 32) == aff) {
431 				u64 offset = ptr - gic_data.redist_regions[i].redist_base;
432 				gic_data_rdist_rd_base() = ptr;
433 				gic_data_rdist()->phys_base = gic_data.redist_regions[i].phys_base + offset;
434 				pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
435 					smp_processor_id(), mpidr, i,
436 					&gic_data_rdist()->phys_base);
437 				return 0;
438 			}
439 
440 			if (gic_data.redist_regions[i].single_redist)
441 				break;
442 
443 			if (gic_data.redist_stride) {
444 				ptr += gic_data.redist_stride;
445 			} else {
446 				ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
447 				if (typer & GICR_TYPER_VLPIS)
448 					ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
449 			}
450 		} while (!(typer & GICR_TYPER_LAST));
451 	}
452 
453 	/* We couldn't even deal with ourselves... */
454 	WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
455 	     smp_processor_id(), mpidr);
456 	return -ENODEV;
457 }
458 
459 static void gic_cpu_sys_reg_init(void)
460 {
461 	/*
462 	 * Need to check that the SRE bit has actually been set. If
463 	 * not, it means that SRE is disabled at EL2. We're going to
464 	 * die painfully, and there is nothing we can do about it.
465 	 *
466 	 * Kindly inform the luser.
467 	 */
468 	if (!gic_enable_sre())
469 		pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
470 
471 	/* Set priority mask register */
472 	gic_write_pmr(DEFAULT_PMR_VALUE);
473 
474 	if (static_key_true(&supports_deactivate)) {
475 		/* EOI drops priority only (mode 1) */
476 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop);
477 	} else {
478 		/* EOI deactivates interrupt too (mode 0) */
479 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
480 	}
481 
482 	/* ... and let's hit the road... */
483 	gic_write_grpen1(1);
484 }
485 
486 static int gic_dist_supports_lpis(void)
487 {
488 	return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS);
489 }
490 
491 static void gic_cpu_init(void)
492 {
493 	void __iomem *rbase;
494 
495 	/* Register ourselves with the rest of the world */
496 	if (gic_populate_rdist())
497 		return;
498 
499 	gic_enable_redist(true);
500 
501 	rbase = gic_data_rdist_sgi_base();
502 
503 	gic_cpu_config(rbase, gic_redist_wait_for_rwp);
504 
505 	/* Give LPIs a spin */
506 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
507 		its_cpu_init();
508 
509 	/* initialise system registers */
510 	gic_cpu_sys_reg_init();
511 }
512 
513 #ifdef CONFIG_SMP
514 static int gic_secondary_init(struct notifier_block *nfb,
515 			      unsigned long action, void *hcpu)
516 {
517 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
518 		gic_cpu_init();
519 	return NOTIFY_OK;
520 }
521 
522 /*
523  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
524  * priority because the GIC needs to be up before the ARM generic timers.
525  */
526 static struct notifier_block gic_cpu_notifier = {
527 	.notifier_call = gic_secondary_init,
528 	.priority = 100,
529 };
530 
531 static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
532 				   unsigned long cluster_id)
533 {
534 	int cpu = *base_cpu;
535 	unsigned long mpidr = cpu_logical_map(cpu);
536 	u16 tlist = 0;
537 
538 	while (cpu < nr_cpu_ids) {
539 		/*
540 		 * If we ever get a cluster of more than 16 CPUs, just
541 		 * scream and skip that CPU.
542 		 */
543 		if (WARN_ON((mpidr & 0xff) >= 16))
544 			goto out;
545 
546 		tlist |= 1 << (mpidr & 0xf);
547 
548 		cpu = cpumask_next(cpu, mask);
549 		if (cpu >= nr_cpu_ids)
550 			goto out;
551 
552 		mpidr = cpu_logical_map(cpu);
553 
554 		if (cluster_id != (mpidr & ~0xffUL)) {
555 			cpu--;
556 			goto out;
557 		}
558 	}
559 out:
560 	*base_cpu = cpu;
561 	return tlist;
562 }
563 
564 #define MPIDR_TO_SGI_AFFINITY(cluster_id, level) \
565 	(MPIDR_AFFINITY_LEVEL(cluster_id, level) \
566 		<< ICC_SGI1R_AFFINITY_## level ##_SHIFT)
567 
568 static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
569 {
570 	u64 val;
571 
572 	val = (MPIDR_TO_SGI_AFFINITY(cluster_id, 3)	|
573 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 2)	|
574 	       irq << ICC_SGI1R_SGI_ID_SHIFT		|
575 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 1)	|
576 	       tlist << ICC_SGI1R_TARGET_LIST_SHIFT);
577 
578 	pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
579 	gic_write_sgi1r(val);
580 }
581 
582 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
583 {
584 	int cpu;
585 
586 	if (WARN_ON(irq >= 16))
587 		return;
588 
589 	/*
590 	 * Ensure that stores to Normal memory are visible to the
591 	 * other CPUs before issuing the IPI.
592 	 */
593 	smp_wmb();
594 
595 	for_each_cpu(cpu, mask) {
596 		unsigned long cluster_id = cpu_logical_map(cpu) & ~0xffUL;
597 		u16 tlist;
598 
599 		tlist = gic_compute_target_list(&cpu, mask, cluster_id);
600 		gic_send_sgi(cluster_id, tlist, irq);
601 	}
602 
603 	/* Force the above writes to ICC_SGI1R_EL1 to be executed */
604 	isb();
605 }
606 
607 static void gic_smp_init(void)
608 {
609 	set_smp_cross_call(gic_raise_softirq);
610 	register_cpu_notifier(&gic_cpu_notifier);
611 }
612 
613 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
614 			    bool force)
615 {
616 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
617 	void __iomem *reg;
618 	int enabled;
619 	u64 val;
620 
621 	if (gic_irq_in_rdist(d))
622 		return -EINVAL;
623 
624 	/* If interrupt was enabled, disable it first */
625 	enabled = gic_peek_irq(d, GICD_ISENABLER);
626 	if (enabled)
627 		gic_mask_irq(d);
628 
629 	reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
630 	val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
631 
632 	gic_write_irouter(val, reg);
633 
634 	/*
635 	 * If the interrupt was enabled, enabled it again. Otherwise,
636 	 * just wait for the distributor to have digested our changes.
637 	 */
638 	if (enabled)
639 		gic_unmask_irq(d);
640 	else
641 		gic_dist_wait_for_rwp();
642 
643 	return IRQ_SET_MASK_OK_DONE;
644 }
645 #else
646 #define gic_set_affinity	NULL
647 #define gic_smp_init()		do { } while(0)
648 #endif
649 
650 #ifdef CONFIG_CPU_PM
651 static int gic_cpu_pm_notifier(struct notifier_block *self,
652 			       unsigned long cmd, void *v)
653 {
654 	if (cmd == CPU_PM_EXIT) {
655 		gic_enable_redist(true);
656 		gic_cpu_sys_reg_init();
657 	} else if (cmd == CPU_PM_ENTER) {
658 		gic_write_grpen1(0);
659 		gic_enable_redist(false);
660 	}
661 	return NOTIFY_OK;
662 }
663 
664 static struct notifier_block gic_cpu_pm_notifier_block = {
665 	.notifier_call = gic_cpu_pm_notifier,
666 };
667 
668 static void gic_cpu_pm_init(void)
669 {
670 	cpu_pm_register_notifier(&gic_cpu_pm_notifier_block);
671 }
672 
673 #else
674 static inline void gic_cpu_pm_init(void) { }
675 #endif /* CONFIG_CPU_PM */
676 
677 static struct irq_chip gic_chip = {
678 	.name			= "GICv3",
679 	.irq_mask		= gic_mask_irq,
680 	.irq_unmask		= gic_unmask_irq,
681 	.irq_eoi		= gic_eoi_irq,
682 	.irq_set_type		= gic_set_type,
683 	.irq_set_affinity	= gic_set_affinity,
684 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
685 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
686 	.flags			= IRQCHIP_SET_TYPE_MASKED,
687 };
688 
689 static struct irq_chip gic_eoimode1_chip = {
690 	.name			= "GICv3",
691 	.irq_mask		= gic_eoimode1_mask_irq,
692 	.irq_unmask		= gic_unmask_irq,
693 	.irq_eoi		= gic_eoimode1_eoi_irq,
694 	.irq_set_type		= gic_set_type,
695 	.irq_set_affinity	= gic_set_affinity,
696 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
697 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
698 	.irq_set_vcpu_affinity	= gic_irq_set_vcpu_affinity,
699 	.flags			= IRQCHIP_SET_TYPE_MASKED,
700 };
701 
702 #define GIC_ID_NR		(1U << gic_data.rdists.id_bits)
703 
704 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
705 			      irq_hw_number_t hw)
706 {
707 	struct irq_chip *chip = &gic_chip;
708 
709 	if (static_key_true(&supports_deactivate))
710 		chip = &gic_eoimode1_chip;
711 
712 	/* SGIs are private to the core kernel */
713 	if (hw < 16)
714 		return -EPERM;
715 	/* Nothing here */
716 	if (hw >= gic_data.irq_nr && hw < 8192)
717 		return -EPERM;
718 	/* Off limits */
719 	if (hw >= GIC_ID_NR)
720 		return -EPERM;
721 
722 	/* PPIs */
723 	if (hw < 32) {
724 		irq_set_percpu_devid(irq);
725 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
726 				    handle_percpu_devid_irq, NULL, NULL);
727 		irq_set_status_flags(irq, IRQ_NOAUTOEN);
728 	}
729 	/* SPIs */
730 	if (hw >= 32 && hw < gic_data.irq_nr) {
731 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
732 				    handle_fasteoi_irq, NULL, NULL);
733 		irq_set_probe(irq);
734 	}
735 	/* LPIs */
736 	if (hw >= 8192 && hw < GIC_ID_NR) {
737 		if (!gic_dist_supports_lpis())
738 			return -EPERM;
739 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
740 				    handle_fasteoi_irq, NULL, NULL);
741 	}
742 
743 	return 0;
744 }
745 
746 static int gic_irq_domain_translate(struct irq_domain *d,
747 				    struct irq_fwspec *fwspec,
748 				    unsigned long *hwirq,
749 				    unsigned int *type)
750 {
751 	if (is_of_node(fwspec->fwnode)) {
752 		if (fwspec->param_count < 3)
753 			return -EINVAL;
754 
755 		switch (fwspec->param[0]) {
756 		case 0:			/* SPI */
757 			*hwirq = fwspec->param[1] + 32;
758 			break;
759 		case 1:			/* PPI */
760 			*hwirq = fwspec->param[1] + 16;
761 			break;
762 		case GIC_IRQ_TYPE_LPI:	/* LPI */
763 			*hwirq = fwspec->param[1];
764 			break;
765 		default:
766 			return -EINVAL;
767 		}
768 
769 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
770 		return 0;
771 	}
772 
773 	if (is_fwnode_irqchip(fwspec->fwnode)) {
774 		if(fwspec->param_count != 2)
775 			return -EINVAL;
776 
777 		*hwirq = fwspec->param[0];
778 		*type = fwspec->param[1];
779 		return 0;
780 	}
781 
782 	return -EINVAL;
783 }
784 
785 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
786 				unsigned int nr_irqs, void *arg)
787 {
788 	int i, ret;
789 	irq_hw_number_t hwirq;
790 	unsigned int type = IRQ_TYPE_NONE;
791 	struct irq_fwspec *fwspec = arg;
792 
793 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
794 	if (ret)
795 		return ret;
796 
797 	for (i = 0; i < nr_irqs; i++)
798 		gic_irq_domain_map(domain, virq + i, hwirq + i);
799 
800 	return 0;
801 }
802 
803 static void gic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
804 				unsigned int nr_irqs)
805 {
806 	int i;
807 
808 	for (i = 0; i < nr_irqs; i++) {
809 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
810 		irq_set_handler(virq + i, NULL);
811 		irq_domain_reset_irq_data(d);
812 	}
813 }
814 
815 static const struct irq_domain_ops gic_irq_domain_ops = {
816 	.translate = gic_irq_domain_translate,
817 	.alloc = gic_irq_domain_alloc,
818 	.free = gic_irq_domain_free,
819 };
820 
821 static void gicv3_enable_quirks(void)
822 {
823 #ifdef CONFIG_ARM64
824 	if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_23154))
825 		static_branch_enable(&is_cavium_thunderx);
826 #endif
827 }
828 
829 static int __init gic_init_bases(void __iomem *dist_base,
830 				 struct redist_region *rdist_regs,
831 				 u32 nr_redist_regions,
832 				 u64 redist_stride,
833 				 struct fwnode_handle *handle)
834 {
835 	struct device_node *node;
836 	u32 typer;
837 	int gic_irqs;
838 	int err;
839 
840 	if (!is_hyp_mode_available())
841 		static_key_slow_dec(&supports_deactivate);
842 
843 	if (static_key_true(&supports_deactivate))
844 		pr_info("GIC: Using split EOI/Deactivate mode\n");
845 
846 	gic_data.dist_base = dist_base;
847 	gic_data.redist_regions = rdist_regs;
848 	gic_data.nr_redist_regions = nr_redist_regions;
849 	gic_data.redist_stride = redist_stride;
850 
851 	gicv3_enable_quirks();
852 
853 	/*
854 	 * Find out how many interrupts are supported.
855 	 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
856 	 */
857 	typer = readl_relaxed(gic_data.dist_base + GICD_TYPER);
858 	gic_data.rdists.id_bits = GICD_TYPER_ID_BITS(typer);
859 	gic_irqs = GICD_TYPER_IRQS(typer);
860 	if (gic_irqs > 1020)
861 		gic_irqs = 1020;
862 	gic_data.irq_nr = gic_irqs;
863 
864 	gic_data.domain = irq_domain_create_tree(handle, &gic_irq_domain_ops,
865 						 &gic_data);
866 	gic_data.rdists.rdist = alloc_percpu(typeof(*gic_data.rdists.rdist));
867 
868 	if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdists.rdist)) {
869 		err = -ENOMEM;
870 		goto out_free;
871 	}
872 
873 	set_handle_irq(gic_handle_irq);
874 
875 	node = to_of_node(handle);
876 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis() &&
877 	    node) /* Temp hack to prevent ITS init for ACPI */
878 		its_init(node, &gic_data.rdists, gic_data.domain);
879 
880 	gic_smp_init();
881 	gic_dist_init();
882 	gic_cpu_init();
883 	gic_cpu_pm_init();
884 
885 	return 0;
886 
887 out_free:
888 	if (gic_data.domain)
889 		irq_domain_remove(gic_data.domain);
890 	free_percpu(gic_data.rdists.rdist);
891 	return err;
892 }
893 
894 static int __init gic_validate_dist_version(void __iomem *dist_base)
895 {
896 	u32 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
897 
898 	if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4)
899 		return -ENODEV;
900 
901 	return 0;
902 }
903 
904 static int __init gic_of_init(struct device_node *node, struct device_node *parent)
905 {
906 	void __iomem *dist_base;
907 	struct redist_region *rdist_regs;
908 	u64 redist_stride;
909 	u32 nr_redist_regions;
910 	int err, i;
911 
912 	dist_base = of_iomap(node, 0);
913 	if (!dist_base) {
914 		pr_err("%s: unable to map gic dist registers\n",
915 			node->full_name);
916 		return -ENXIO;
917 	}
918 
919 	err = gic_validate_dist_version(dist_base);
920 	if (err) {
921 		pr_err("%s: no distributor detected, giving up\n",
922 			node->full_name);
923 		goto out_unmap_dist;
924 	}
925 
926 	if (of_property_read_u32(node, "#redistributor-regions", &nr_redist_regions))
927 		nr_redist_regions = 1;
928 
929 	rdist_regs = kzalloc(sizeof(*rdist_regs) * nr_redist_regions, GFP_KERNEL);
930 	if (!rdist_regs) {
931 		err = -ENOMEM;
932 		goto out_unmap_dist;
933 	}
934 
935 	for (i = 0; i < nr_redist_regions; i++) {
936 		struct resource res;
937 		int ret;
938 
939 		ret = of_address_to_resource(node, 1 + i, &res);
940 		rdist_regs[i].redist_base = of_iomap(node, 1 + i);
941 		if (ret || !rdist_regs[i].redist_base) {
942 			pr_err("%s: couldn't map region %d\n",
943 			       node->full_name, i);
944 			err = -ENODEV;
945 			goto out_unmap_rdist;
946 		}
947 		rdist_regs[i].phys_base = res.start;
948 	}
949 
950 	if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
951 		redist_stride = 0;
952 
953 	err = gic_init_bases(dist_base, rdist_regs, nr_redist_regions,
954 			     redist_stride, &node->fwnode);
955 	if (!err)
956 		return 0;
957 
958 out_unmap_rdist:
959 	for (i = 0; i < nr_redist_regions; i++)
960 		if (rdist_regs[i].redist_base)
961 			iounmap(rdist_regs[i].redist_base);
962 	kfree(rdist_regs);
963 out_unmap_dist:
964 	iounmap(dist_base);
965 	return err;
966 }
967 
968 IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);
969 
970 #ifdef CONFIG_ACPI
971 static void __iomem *dist_base;
972 static struct redist_region *redist_regs __initdata;
973 static u32 nr_redist_regions __initdata;
974 static bool single_redist;
975 
976 static void __init
977 gic_acpi_register_redist(phys_addr_t phys_base, void __iomem *redist_base)
978 {
979 	static int count = 0;
980 
981 	redist_regs[count].phys_base = phys_base;
982 	redist_regs[count].redist_base = redist_base;
983 	redist_regs[count].single_redist = single_redist;
984 	count++;
985 }
986 
987 static int __init
988 gic_acpi_parse_madt_redist(struct acpi_subtable_header *header,
989 			   const unsigned long end)
990 {
991 	struct acpi_madt_generic_redistributor *redist =
992 			(struct acpi_madt_generic_redistributor *)header;
993 	void __iomem *redist_base;
994 
995 	redist_base = ioremap(redist->base_address, redist->length);
996 	if (!redist_base) {
997 		pr_err("Couldn't map GICR region @%llx\n", redist->base_address);
998 		return -ENOMEM;
999 	}
1000 
1001 	gic_acpi_register_redist(redist->base_address, redist_base);
1002 	return 0;
1003 }
1004 
1005 static int __init
1006 gic_acpi_parse_madt_gicc(struct acpi_subtable_header *header,
1007 			 const unsigned long end)
1008 {
1009 	struct acpi_madt_generic_interrupt *gicc =
1010 				(struct acpi_madt_generic_interrupt *)header;
1011 	u32 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
1012 	u32 size = reg == GIC_PIDR2_ARCH_GICv4 ? SZ_64K * 4 : SZ_64K * 2;
1013 	void __iomem *redist_base;
1014 
1015 	redist_base = ioremap(gicc->gicr_base_address, size);
1016 	if (!redist_base)
1017 		return -ENOMEM;
1018 
1019 	gic_acpi_register_redist(gicc->gicr_base_address, redist_base);
1020 	return 0;
1021 }
1022 
1023 static int __init gic_acpi_collect_gicr_base(void)
1024 {
1025 	acpi_tbl_entry_handler redist_parser;
1026 	enum acpi_madt_type type;
1027 
1028 	if (single_redist) {
1029 		type = ACPI_MADT_TYPE_GENERIC_INTERRUPT;
1030 		redist_parser = gic_acpi_parse_madt_gicc;
1031 	} else {
1032 		type = ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR;
1033 		redist_parser = gic_acpi_parse_madt_redist;
1034 	}
1035 
1036 	/* Collect redistributor base addresses in GICR entries */
1037 	if (acpi_table_parse_madt(type, redist_parser, 0) > 0)
1038 		return 0;
1039 
1040 	pr_info("No valid GICR entries exist\n");
1041 	return -ENODEV;
1042 }
1043 
1044 static int __init gic_acpi_match_gicr(struct acpi_subtable_header *header,
1045 				  const unsigned long end)
1046 {
1047 	/* Subtable presence means that redist exists, that's it */
1048 	return 0;
1049 }
1050 
1051 static int __init gic_acpi_match_gicc(struct acpi_subtable_header *header,
1052 				      const unsigned long end)
1053 {
1054 	struct acpi_madt_generic_interrupt *gicc =
1055 				(struct acpi_madt_generic_interrupt *)header;
1056 
1057 	/*
1058 	 * If GICC is enabled and has valid gicr base address, then it means
1059 	 * GICR base is presented via GICC
1060 	 */
1061 	if ((gicc->flags & ACPI_MADT_ENABLED) && gicc->gicr_base_address)
1062 		return 0;
1063 
1064 	return -ENODEV;
1065 }
1066 
1067 static int __init gic_acpi_count_gicr_regions(void)
1068 {
1069 	int count;
1070 
1071 	/*
1072 	 * Count how many redistributor regions we have. It is not allowed
1073 	 * to mix redistributor description, GICR and GICC subtables have to be
1074 	 * mutually exclusive.
1075 	 */
1076 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
1077 				      gic_acpi_match_gicr, 0);
1078 	if (count > 0) {
1079 		single_redist = false;
1080 		return count;
1081 	}
1082 
1083 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1084 				      gic_acpi_match_gicc, 0);
1085 	if (count > 0)
1086 		single_redist = true;
1087 
1088 	return count;
1089 }
1090 
1091 static bool __init acpi_validate_gic_table(struct acpi_subtable_header *header,
1092 					   struct acpi_probe_entry *ape)
1093 {
1094 	struct acpi_madt_generic_distributor *dist;
1095 	int count;
1096 
1097 	dist = (struct acpi_madt_generic_distributor *)header;
1098 	if (dist->version != ape->driver_data)
1099 		return false;
1100 
1101 	/* We need to do that exercise anyway, the sooner the better */
1102 	count = gic_acpi_count_gicr_regions();
1103 	if (count <= 0)
1104 		return false;
1105 
1106 	nr_redist_regions = count;
1107 	return true;
1108 }
1109 
1110 #define ACPI_GICV3_DIST_MEM_SIZE (SZ_64K)
1111 
1112 static int __init
1113 gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
1114 {
1115 	struct acpi_madt_generic_distributor *dist;
1116 	struct fwnode_handle *domain_handle;
1117 	int i, err;
1118 
1119 	/* Get distributor base address */
1120 	dist = (struct acpi_madt_generic_distributor *)header;
1121 	dist_base = ioremap(dist->base_address, ACPI_GICV3_DIST_MEM_SIZE);
1122 	if (!dist_base) {
1123 		pr_err("Unable to map GICD registers\n");
1124 		return -ENOMEM;
1125 	}
1126 
1127 	err = gic_validate_dist_version(dist_base);
1128 	if (err) {
1129 		pr_err("No distributor detected at @%p, giving up", dist_base);
1130 		goto out_dist_unmap;
1131 	}
1132 
1133 	redist_regs = kzalloc(sizeof(*redist_regs) * nr_redist_regions,
1134 			      GFP_KERNEL);
1135 	if (!redist_regs) {
1136 		err = -ENOMEM;
1137 		goto out_dist_unmap;
1138 	}
1139 
1140 	err = gic_acpi_collect_gicr_base();
1141 	if (err)
1142 		goto out_redist_unmap;
1143 
1144 	domain_handle = irq_domain_alloc_fwnode(dist_base);
1145 	if (!domain_handle) {
1146 		err = -ENOMEM;
1147 		goto out_redist_unmap;
1148 	}
1149 
1150 	err = gic_init_bases(dist_base, redist_regs, nr_redist_regions, 0,
1151 			     domain_handle);
1152 	if (err)
1153 		goto out_fwhandle_free;
1154 
1155 	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
1156 	return 0;
1157 
1158 out_fwhandle_free:
1159 	irq_domain_free_fwnode(domain_handle);
1160 out_redist_unmap:
1161 	for (i = 0; i < nr_redist_regions; i++)
1162 		if (redist_regs[i].redist_base)
1163 			iounmap(redist_regs[i].redist_base);
1164 	kfree(redist_regs);
1165 out_dist_unmap:
1166 	iounmap(dist_base);
1167 	return err;
1168 }
1169 IRQCHIP_ACPI_DECLARE(gic_v3, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1170 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V3,
1171 		     gic_acpi_init);
1172 IRQCHIP_ACPI_DECLARE(gic_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1173 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V4,
1174 		     gic_acpi_init);
1175 IRQCHIP_ACPI_DECLARE(gic_v3_or_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1176 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_NONE,
1177 		     gic_acpi_init);
1178 #endif
1179