xref: /openbmc/linux/drivers/irqchip/irq-gic-v3.c (revision 78700c0a)
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 #define pr_fmt(fmt)	"GICv3: " fmt
19 
20 #include <linux/acpi.h>
21 #include <linux/cpu.h>
22 #include <linux/cpu_pm.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/irqdomain.h>
26 #include <linux/of.h>
27 #include <linux/of_address.h>
28 #include <linux/of_irq.h>
29 #include <linux/percpu.h>
30 #include <linux/slab.h>
31 
32 #include <linux/irqchip.h>
33 #include <linux/irqchip/arm-gic-common.h>
34 #include <linux/irqchip/arm-gic-v3.h>
35 #include <linux/irqchip/irq-partition-percpu.h>
36 
37 #include <asm/cputype.h>
38 #include <asm/exception.h>
39 #include <asm/smp_plat.h>
40 #include <asm/virt.h>
41 
42 #include "irq-gic-common.h"
43 
44 struct redist_region {
45 	void __iomem		*redist_base;
46 	phys_addr_t		phys_base;
47 	bool			single_redist;
48 };
49 
50 struct gic_chip_data {
51 	struct fwnode_handle	*fwnode;
52 	void __iomem		*dist_base;
53 	struct redist_region	*redist_regions;
54 	struct rdists		rdists;
55 	struct irq_domain	*domain;
56 	u64			redist_stride;
57 	u32			nr_redist_regions;
58 	unsigned int		irq_nr;
59 	struct partition_desc	*ppi_descs[16];
60 };
61 
62 static struct gic_chip_data gic_data __read_mostly;
63 static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
64 
65 static struct gic_kvm_info gic_v3_kvm_info;
66 
67 #define gic_data_rdist()		(this_cpu_ptr(gic_data.rdists.rdist))
68 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
69 #define gic_data_rdist_sgi_base()	(gic_data_rdist_rd_base() + SZ_64K)
70 
71 /* Our default, arbitrary priority value. Linux only uses one anyway. */
72 #define DEFAULT_PMR_VALUE	0xf0
73 
74 static inline unsigned int gic_irq(struct irq_data *d)
75 {
76 	return d->hwirq;
77 }
78 
79 static inline int gic_irq_in_rdist(struct irq_data *d)
80 {
81 	return gic_irq(d) < 32;
82 }
83 
84 static inline void __iomem *gic_dist_base(struct irq_data *d)
85 {
86 	if (gic_irq_in_rdist(d))	/* SGI+PPI -> SGI_base for this CPU */
87 		return gic_data_rdist_sgi_base();
88 
89 	if (d->hwirq <= 1023)		/* SPI -> dist_base */
90 		return gic_data.dist_base;
91 
92 	return NULL;
93 }
94 
95 static void gic_do_wait_for_rwp(void __iomem *base)
96 {
97 	u32 count = 1000000;	/* 1s! */
98 
99 	while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
100 		count--;
101 		if (!count) {
102 			pr_err_ratelimited("RWP timeout, gone fishing\n");
103 			return;
104 		}
105 		cpu_relax();
106 		udelay(1);
107 	};
108 }
109 
110 /* Wait for completion of a distributor change */
111 static void gic_dist_wait_for_rwp(void)
112 {
113 	gic_do_wait_for_rwp(gic_data.dist_base);
114 }
115 
116 /* Wait for completion of a redistributor change */
117 static void gic_redist_wait_for_rwp(void)
118 {
119 	gic_do_wait_for_rwp(gic_data_rdist_rd_base());
120 }
121 
122 #ifdef CONFIG_ARM64
123 static DEFINE_STATIC_KEY_FALSE(is_cavium_thunderx);
124 
125 static u64 __maybe_unused gic_read_iar(void)
126 {
127 	if (static_branch_unlikely(&is_cavium_thunderx))
128 		return gic_read_iar_cavium_thunderx();
129 	else
130 		return gic_read_iar_common();
131 }
132 #endif
133 
134 static void gic_enable_redist(bool enable)
135 {
136 	void __iomem *rbase;
137 	u32 count = 1000000;	/* 1s! */
138 	u32 val;
139 
140 	rbase = gic_data_rdist_rd_base();
141 
142 	val = readl_relaxed(rbase + GICR_WAKER);
143 	if (enable)
144 		/* Wake up this CPU redistributor */
145 		val &= ~GICR_WAKER_ProcessorSleep;
146 	else
147 		val |= GICR_WAKER_ProcessorSleep;
148 	writel_relaxed(val, rbase + GICR_WAKER);
149 
150 	if (!enable) {		/* Check that GICR_WAKER is writeable */
151 		val = readl_relaxed(rbase + GICR_WAKER);
152 		if (!(val & GICR_WAKER_ProcessorSleep))
153 			return;	/* No PM support in this redistributor */
154 	}
155 
156 	while (count--) {
157 		val = readl_relaxed(rbase + GICR_WAKER);
158 		if (enable ^ (val & GICR_WAKER_ChildrenAsleep))
159 			break;
160 		cpu_relax();
161 		udelay(1);
162 	};
163 	if (!count)
164 		pr_err_ratelimited("redistributor failed to %s...\n",
165 				   enable ? "wakeup" : "sleep");
166 }
167 
168 /*
169  * Routines to disable, enable, EOI and route interrupts
170  */
171 static int gic_peek_irq(struct irq_data *d, u32 offset)
172 {
173 	u32 mask = 1 << (gic_irq(d) % 32);
174 	void __iomem *base;
175 
176 	if (gic_irq_in_rdist(d))
177 		base = gic_data_rdist_sgi_base();
178 	else
179 		base = gic_data.dist_base;
180 
181 	return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
182 }
183 
184 static void gic_poke_irq(struct irq_data *d, u32 offset)
185 {
186 	u32 mask = 1 << (gic_irq(d) % 32);
187 	void (*rwp_wait)(void);
188 	void __iomem *base;
189 
190 	if (gic_irq_in_rdist(d)) {
191 		base = gic_data_rdist_sgi_base();
192 		rwp_wait = gic_redist_wait_for_rwp;
193 	} else {
194 		base = gic_data.dist_base;
195 		rwp_wait = gic_dist_wait_for_rwp;
196 	}
197 
198 	writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
199 	rwp_wait();
200 }
201 
202 static void gic_mask_irq(struct irq_data *d)
203 {
204 	gic_poke_irq(d, GICD_ICENABLER);
205 }
206 
207 static void gic_eoimode1_mask_irq(struct irq_data *d)
208 {
209 	gic_mask_irq(d);
210 	/*
211 	 * When masking a forwarded interrupt, make sure it is
212 	 * deactivated as well.
213 	 *
214 	 * This ensures that an interrupt that is getting
215 	 * disabled/masked will not get "stuck", because there is
216 	 * noone to deactivate it (guest is being terminated).
217 	 */
218 	if (irqd_is_forwarded_to_vcpu(d))
219 		gic_poke_irq(d, GICD_ICACTIVER);
220 }
221 
222 static void gic_unmask_irq(struct irq_data *d)
223 {
224 	gic_poke_irq(d, GICD_ISENABLER);
225 }
226 
227 static int gic_irq_set_irqchip_state(struct irq_data *d,
228 				     enum irqchip_irq_state which, bool val)
229 {
230 	u32 reg;
231 
232 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
233 		return -EINVAL;
234 
235 	switch (which) {
236 	case IRQCHIP_STATE_PENDING:
237 		reg = val ? GICD_ISPENDR : GICD_ICPENDR;
238 		break;
239 
240 	case IRQCHIP_STATE_ACTIVE:
241 		reg = val ? GICD_ISACTIVER : GICD_ICACTIVER;
242 		break;
243 
244 	case IRQCHIP_STATE_MASKED:
245 		reg = val ? GICD_ICENABLER : GICD_ISENABLER;
246 		break;
247 
248 	default:
249 		return -EINVAL;
250 	}
251 
252 	gic_poke_irq(d, reg);
253 	return 0;
254 }
255 
256 static int gic_irq_get_irqchip_state(struct irq_data *d,
257 				     enum irqchip_irq_state which, bool *val)
258 {
259 	if (d->hwirq >= gic_data.irq_nr) /* PPI/SPI only */
260 		return -EINVAL;
261 
262 	switch (which) {
263 	case IRQCHIP_STATE_PENDING:
264 		*val = gic_peek_irq(d, GICD_ISPENDR);
265 		break;
266 
267 	case IRQCHIP_STATE_ACTIVE:
268 		*val = gic_peek_irq(d, GICD_ISACTIVER);
269 		break;
270 
271 	case IRQCHIP_STATE_MASKED:
272 		*val = !gic_peek_irq(d, GICD_ISENABLER);
273 		break;
274 
275 	default:
276 		return -EINVAL;
277 	}
278 
279 	return 0;
280 }
281 
282 static void gic_eoi_irq(struct irq_data *d)
283 {
284 	gic_write_eoir(gic_irq(d));
285 }
286 
287 static void gic_eoimode1_eoi_irq(struct irq_data *d)
288 {
289 	/*
290 	 * No need to deactivate an LPI, or an interrupt that
291 	 * is is getting forwarded to a vcpu.
292 	 */
293 	if (gic_irq(d) >= 8192 || irqd_is_forwarded_to_vcpu(d))
294 		return;
295 	gic_write_dir(gic_irq(d));
296 }
297 
298 static int gic_set_type(struct irq_data *d, unsigned int type)
299 {
300 	unsigned int irq = gic_irq(d);
301 	void (*rwp_wait)(void);
302 	void __iomem *base;
303 
304 	/* Interrupt configuration for SGIs can't be changed */
305 	if (irq < 16)
306 		return -EINVAL;
307 
308 	/* SPIs have restrictions on the supported types */
309 	if (irq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
310 			 type != IRQ_TYPE_EDGE_RISING)
311 		return -EINVAL;
312 
313 	if (gic_irq_in_rdist(d)) {
314 		base = gic_data_rdist_sgi_base();
315 		rwp_wait = gic_redist_wait_for_rwp;
316 	} else {
317 		base = gic_data.dist_base;
318 		rwp_wait = gic_dist_wait_for_rwp;
319 	}
320 
321 	return gic_configure_irq(irq, type, base, rwp_wait);
322 }
323 
324 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
325 {
326 	if (vcpu)
327 		irqd_set_forwarded_to_vcpu(d);
328 	else
329 		irqd_clr_forwarded_to_vcpu(d);
330 	return 0;
331 }
332 
333 static u64 gic_mpidr_to_affinity(unsigned long mpidr)
334 {
335 	u64 aff;
336 
337 	aff = ((u64)MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
338 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
339 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8  |
340 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
341 
342 	return aff;
343 }
344 
345 static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
346 {
347 	u32 irqnr;
348 
349 	do {
350 		irqnr = gic_read_iar();
351 
352 		if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
353 			int err;
354 
355 			if (static_key_true(&supports_deactivate))
356 				gic_write_eoir(irqnr);
357 
358 			err = handle_domain_irq(gic_data.domain, irqnr, regs);
359 			if (err) {
360 				WARN_ONCE(true, "Unexpected interrupt received!\n");
361 				if (static_key_true(&supports_deactivate)) {
362 					if (irqnr < 8192)
363 						gic_write_dir(irqnr);
364 				} else {
365 					gic_write_eoir(irqnr);
366 				}
367 			}
368 			continue;
369 		}
370 		if (irqnr < 16) {
371 			gic_write_eoir(irqnr);
372 			if (static_key_true(&supports_deactivate))
373 				gic_write_dir(irqnr);
374 #ifdef CONFIG_SMP
375 			/*
376 			 * Unlike GICv2, we don't need an smp_rmb() here.
377 			 * The control dependency from gic_read_iar to
378 			 * the ISB in gic_write_eoir is enough to ensure
379 			 * that any shared data read by handle_IPI will
380 			 * be read after the ACK.
381 			 */
382 			handle_IPI(irqnr, regs);
383 #else
384 			WARN_ONCE(true, "Unexpected SGI received!\n");
385 #endif
386 			continue;
387 		}
388 	} while (irqnr != ICC_IAR1_EL1_SPURIOUS);
389 }
390 
391 static void __init gic_dist_init(void)
392 {
393 	unsigned int i;
394 	u64 affinity;
395 	void __iomem *base = gic_data.dist_base;
396 
397 	/* Disable the distributor */
398 	writel_relaxed(0, base + GICD_CTLR);
399 	gic_dist_wait_for_rwp();
400 
401 	/*
402 	 * Configure SPIs as non-secure Group-1. This will only matter
403 	 * if the GIC only has a single security state. This will not
404 	 * do the right thing if the kernel is running in secure mode,
405 	 * but that's not the intended use case anyway.
406 	 */
407 	for (i = 32; i < gic_data.irq_nr; i += 32)
408 		writel_relaxed(~0, base + GICD_IGROUPR + i / 8);
409 
410 	gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
411 
412 	/* Enable distributor with ARE, Group1 */
413 	writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
414 		       base + GICD_CTLR);
415 
416 	/*
417 	 * Set all global interrupts to the boot CPU only. ARE must be
418 	 * enabled.
419 	 */
420 	affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
421 	for (i = 32; i < gic_data.irq_nr; i++)
422 		gic_write_irouter(affinity, base + GICD_IROUTER + i * 8);
423 }
424 
425 static int gic_populate_rdist(void)
426 {
427 	unsigned long mpidr = cpu_logical_map(smp_processor_id());
428 	u64 typer;
429 	u32 aff;
430 	int i;
431 
432 	/*
433 	 * Convert affinity to a 32bit value that can be matched to
434 	 * GICR_TYPER bits [63:32].
435 	 */
436 	aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
437 	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
438 	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
439 	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
440 
441 	for (i = 0; i < gic_data.nr_redist_regions; i++) {
442 		void __iomem *ptr = gic_data.redist_regions[i].redist_base;
443 		u32 reg;
444 
445 		reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
446 		if (reg != GIC_PIDR2_ARCH_GICv3 &&
447 		    reg != GIC_PIDR2_ARCH_GICv4) { /* We're in trouble... */
448 			pr_warn("No redistributor present @%p\n", ptr);
449 			break;
450 		}
451 
452 		do {
453 			typer = gic_read_typer(ptr + GICR_TYPER);
454 			if ((typer >> 32) == aff) {
455 				u64 offset = ptr - gic_data.redist_regions[i].redist_base;
456 				gic_data_rdist_rd_base() = ptr;
457 				gic_data_rdist()->phys_base = gic_data.redist_regions[i].phys_base + offset;
458 				pr_info("CPU%d: found redistributor %lx region %d:%pa\n",
459 					smp_processor_id(), mpidr, i,
460 					&gic_data_rdist()->phys_base);
461 				return 0;
462 			}
463 
464 			if (gic_data.redist_regions[i].single_redist)
465 				break;
466 
467 			if (gic_data.redist_stride) {
468 				ptr += gic_data.redist_stride;
469 			} else {
470 				ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
471 				if (typer & GICR_TYPER_VLPIS)
472 					ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
473 			}
474 		} while (!(typer & GICR_TYPER_LAST));
475 	}
476 
477 	/* We couldn't even deal with ourselves... */
478 	WARN(true, "CPU%d: mpidr %lx has no re-distributor!\n",
479 	     smp_processor_id(), mpidr);
480 	return -ENODEV;
481 }
482 
483 static void gic_cpu_sys_reg_init(void)
484 {
485 	/*
486 	 * Need to check that the SRE bit has actually been set. If
487 	 * not, it means that SRE is disabled at EL2. We're going to
488 	 * die painfully, and there is nothing we can do about it.
489 	 *
490 	 * Kindly inform the luser.
491 	 */
492 	if (!gic_enable_sre())
493 		pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
494 
495 	/* Set priority mask register */
496 	gic_write_pmr(DEFAULT_PMR_VALUE);
497 
498 	if (static_key_true(&supports_deactivate)) {
499 		/* EOI drops priority only (mode 1) */
500 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop);
501 	} else {
502 		/* EOI deactivates interrupt too (mode 0) */
503 		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
504 	}
505 
506 	/* ... and let's hit the road... */
507 	gic_write_grpen1(1);
508 }
509 
510 static int gic_dist_supports_lpis(void)
511 {
512 	return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS);
513 }
514 
515 static void gic_cpu_init(void)
516 {
517 	void __iomem *rbase;
518 
519 	/* Register ourselves with the rest of the world */
520 	if (gic_populate_rdist())
521 		return;
522 
523 	gic_enable_redist(true);
524 
525 	rbase = gic_data_rdist_sgi_base();
526 
527 	/* Configure SGIs/PPIs as non-secure Group-1 */
528 	writel_relaxed(~0, rbase + GICR_IGROUPR0);
529 
530 	gic_cpu_config(rbase, gic_redist_wait_for_rwp);
531 
532 	/* Give LPIs a spin */
533 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
534 		its_cpu_init();
535 
536 	/* initialise system registers */
537 	gic_cpu_sys_reg_init();
538 }
539 
540 #ifdef CONFIG_SMP
541 static int gic_secondary_init(struct notifier_block *nfb,
542 			      unsigned long action, void *hcpu)
543 {
544 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
545 		gic_cpu_init();
546 	return NOTIFY_OK;
547 }
548 
549 /*
550  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
551  * priority because the GIC needs to be up before the ARM generic timers.
552  */
553 static struct notifier_block gic_cpu_notifier = {
554 	.notifier_call = gic_secondary_init,
555 	.priority = 100,
556 };
557 
558 static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
559 				   unsigned long cluster_id)
560 {
561 	int cpu = *base_cpu;
562 	unsigned long mpidr = cpu_logical_map(cpu);
563 	u16 tlist = 0;
564 
565 	while (cpu < nr_cpu_ids) {
566 		/*
567 		 * If we ever get a cluster of more than 16 CPUs, just
568 		 * scream and skip that CPU.
569 		 */
570 		if (WARN_ON((mpidr & 0xff) >= 16))
571 			goto out;
572 
573 		tlist |= 1 << (mpidr & 0xf);
574 
575 		cpu = cpumask_next(cpu, mask);
576 		if (cpu >= nr_cpu_ids)
577 			goto out;
578 
579 		mpidr = cpu_logical_map(cpu);
580 
581 		if (cluster_id != (mpidr & ~0xffUL)) {
582 			cpu--;
583 			goto out;
584 		}
585 	}
586 out:
587 	*base_cpu = cpu;
588 	return tlist;
589 }
590 
591 #define MPIDR_TO_SGI_AFFINITY(cluster_id, level) \
592 	(MPIDR_AFFINITY_LEVEL(cluster_id, level) \
593 		<< ICC_SGI1R_AFFINITY_## level ##_SHIFT)
594 
595 static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
596 {
597 	u64 val;
598 
599 	val = (MPIDR_TO_SGI_AFFINITY(cluster_id, 3)	|
600 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 2)	|
601 	       irq << ICC_SGI1R_SGI_ID_SHIFT		|
602 	       MPIDR_TO_SGI_AFFINITY(cluster_id, 1)	|
603 	       tlist << ICC_SGI1R_TARGET_LIST_SHIFT);
604 
605 	pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
606 	gic_write_sgi1r(val);
607 }
608 
609 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
610 {
611 	int cpu;
612 
613 	if (WARN_ON(irq >= 16))
614 		return;
615 
616 	/*
617 	 * Ensure that stores to Normal memory are visible to the
618 	 * other CPUs before issuing the IPI.
619 	 */
620 	smp_wmb();
621 
622 	for_each_cpu(cpu, mask) {
623 		unsigned long cluster_id = cpu_logical_map(cpu) & ~0xffUL;
624 		u16 tlist;
625 
626 		tlist = gic_compute_target_list(&cpu, mask, cluster_id);
627 		gic_send_sgi(cluster_id, tlist, irq);
628 	}
629 
630 	/* Force the above writes to ICC_SGI1R_EL1 to be executed */
631 	isb();
632 }
633 
634 static void gic_smp_init(void)
635 {
636 	set_smp_cross_call(gic_raise_softirq);
637 	register_cpu_notifier(&gic_cpu_notifier);
638 }
639 
640 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
641 			    bool force)
642 {
643 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
644 	void __iomem *reg;
645 	int enabled;
646 	u64 val;
647 
648 	if (gic_irq_in_rdist(d))
649 		return -EINVAL;
650 
651 	/* If interrupt was enabled, disable it first */
652 	enabled = gic_peek_irq(d, GICD_ISENABLER);
653 	if (enabled)
654 		gic_mask_irq(d);
655 
656 	reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
657 	val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
658 
659 	gic_write_irouter(val, reg);
660 
661 	/*
662 	 * If the interrupt was enabled, enabled it again. Otherwise,
663 	 * just wait for the distributor to have digested our changes.
664 	 */
665 	if (enabled)
666 		gic_unmask_irq(d);
667 	else
668 		gic_dist_wait_for_rwp();
669 
670 	return IRQ_SET_MASK_OK_DONE;
671 }
672 #else
673 #define gic_set_affinity	NULL
674 #define gic_smp_init()		do { } while(0)
675 #endif
676 
677 #ifdef CONFIG_CPU_PM
678 static int gic_cpu_pm_notifier(struct notifier_block *self,
679 			       unsigned long cmd, void *v)
680 {
681 	if (cmd == CPU_PM_EXIT) {
682 		gic_enable_redist(true);
683 		gic_cpu_sys_reg_init();
684 	} else if (cmd == CPU_PM_ENTER) {
685 		gic_write_grpen1(0);
686 		gic_enable_redist(false);
687 	}
688 	return NOTIFY_OK;
689 }
690 
691 static struct notifier_block gic_cpu_pm_notifier_block = {
692 	.notifier_call = gic_cpu_pm_notifier,
693 };
694 
695 static void gic_cpu_pm_init(void)
696 {
697 	cpu_pm_register_notifier(&gic_cpu_pm_notifier_block);
698 }
699 
700 #else
701 static inline void gic_cpu_pm_init(void) { }
702 #endif /* CONFIG_CPU_PM */
703 
704 static struct irq_chip gic_chip = {
705 	.name			= "GICv3",
706 	.irq_mask		= gic_mask_irq,
707 	.irq_unmask		= gic_unmask_irq,
708 	.irq_eoi		= gic_eoi_irq,
709 	.irq_set_type		= gic_set_type,
710 	.irq_set_affinity	= gic_set_affinity,
711 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
712 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
713 	.flags			= IRQCHIP_SET_TYPE_MASKED,
714 };
715 
716 static struct irq_chip gic_eoimode1_chip = {
717 	.name			= "GICv3",
718 	.irq_mask		= gic_eoimode1_mask_irq,
719 	.irq_unmask		= gic_unmask_irq,
720 	.irq_eoi		= gic_eoimode1_eoi_irq,
721 	.irq_set_type		= gic_set_type,
722 	.irq_set_affinity	= gic_set_affinity,
723 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
724 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
725 	.irq_set_vcpu_affinity	= gic_irq_set_vcpu_affinity,
726 	.flags			= IRQCHIP_SET_TYPE_MASKED,
727 };
728 
729 #define GIC_ID_NR		(1U << gic_data.rdists.id_bits)
730 
731 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
732 			      irq_hw_number_t hw)
733 {
734 	struct irq_chip *chip = &gic_chip;
735 
736 	if (static_key_true(&supports_deactivate))
737 		chip = &gic_eoimode1_chip;
738 
739 	/* SGIs are private to the core kernel */
740 	if (hw < 16)
741 		return -EPERM;
742 	/* Nothing here */
743 	if (hw >= gic_data.irq_nr && hw < 8192)
744 		return -EPERM;
745 	/* Off limits */
746 	if (hw >= GIC_ID_NR)
747 		return -EPERM;
748 
749 	/* PPIs */
750 	if (hw < 32) {
751 		irq_set_percpu_devid(irq);
752 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
753 				    handle_percpu_devid_irq, NULL, NULL);
754 		irq_set_status_flags(irq, IRQ_NOAUTOEN);
755 	}
756 	/* SPIs */
757 	if (hw >= 32 && hw < gic_data.irq_nr) {
758 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
759 				    handle_fasteoi_irq, NULL, NULL);
760 		irq_set_probe(irq);
761 	}
762 	/* LPIs */
763 	if (hw >= 8192 && hw < GIC_ID_NR) {
764 		if (!gic_dist_supports_lpis())
765 			return -EPERM;
766 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
767 				    handle_fasteoi_irq, NULL, NULL);
768 	}
769 
770 	return 0;
771 }
772 
773 static int gic_irq_domain_translate(struct irq_domain *d,
774 				    struct irq_fwspec *fwspec,
775 				    unsigned long *hwirq,
776 				    unsigned int *type)
777 {
778 	if (is_of_node(fwspec->fwnode)) {
779 		if (fwspec->param_count < 3)
780 			return -EINVAL;
781 
782 		switch (fwspec->param[0]) {
783 		case 0:			/* SPI */
784 			*hwirq = fwspec->param[1] + 32;
785 			break;
786 		case 1:			/* PPI */
787 			*hwirq = fwspec->param[1] + 16;
788 			break;
789 		case GIC_IRQ_TYPE_LPI:	/* LPI */
790 			*hwirq = fwspec->param[1];
791 			break;
792 		default:
793 			return -EINVAL;
794 		}
795 
796 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
797 		return 0;
798 	}
799 
800 	if (is_fwnode_irqchip(fwspec->fwnode)) {
801 		if(fwspec->param_count != 2)
802 			return -EINVAL;
803 
804 		*hwirq = fwspec->param[0];
805 		*type = fwspec->param[1];
806 		return 0;
807 	}
808 
809 	return -EINVAL;
810 }
811 
812 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
813 				unsigned int nr_irqs, void *arg)
814 {
815 	int i, ret;
816 	irq_hw_number_t hwirq;
817 	unsigned int type = IRQ_TYPE_NONE;
818 	struct irq_fwspec *fwspec = arg;
819 
820 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
821 	if (ret)
822 		return ret;
823 
824 	for (i = 0; i < nr_irqs; i++)
825 		gic_irq_domain_map(domain, virq + i, hwirq + i);
826 
827 	return 0;
828 }
829 
830 static void gic_irq_domain_free(struct irq_domain *domain, unsigned int virq,
831 				unsigned int nr_irqs)
832 {
833 	int i;
834 
835 	for (i = 0; i < nr_irqs; i++) {
836 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
837 		irq_set_handler(virq + i, NULL);
838 		irq_domain_reset_irq_data(d);
839 	}
840 }
841 
842 static int gic_irq_domain_select(struct irq_domain *d,
843 				 struct irq_fwspec *fwspec,
844 				 enum irq_domain_bus_token bus_token)
845 {
846 	/* Not for us */
847         if (fwspec->fwnode != d->fwnode)
848 		return 0;
849 
850 	/* If this is not DT, then we have a single domain */
851 	if (!is_of_node(fwspec->fwnode))
852 		return 1;
853 
854 	/*
855 	 * If this is a PPI and we have a 4th (non-null) parameter,
856 	 * then we need to match the partition domain.
857 	 */
858 	if (fwspec->param_count >= 4 &&
859 	    fwspec->param[0] == 1 && fwspec->param[3] != 0)
860 		return d == partition_get_domain(gic_data.ppi_descs[fwspec->param[1]]);
861 
862 	return d == gic_data.domain;
863 }
864 
865 static const struct irq_domain_ops gic_irq_domain_ops = {
866 	.translate = gic_irq_domain_translate,
867 	.alloc = gic_irq_domain_alloc,
868 	.free = gic_irq_domain_free,
869 	.select = gic_irq_domain_select,
870 };
871 
872 static int partition_domain_translate(struct irq_domain *d,
873 				      struct irq_fwspec *fwspec,
874 				      unsigned long *hwirq,
875 				      unsigned int *type)
876 {
877 	struct device_node *np;
878 	int ret;
879 
880 	np = of_find_node_by_phandle(fwspec->param[3]);
881 	if (WARN_ON(!np))
882 		return -EINVAL;
883 
884 	ret = partition_translate_id(gic_data.ppi_descs[fwspec->param[1]],
885 				     of_node_to_fwnode(np));
886 	if (ret < 0)
887 		return ret;
888 
889 	*hwirq = ret;
890 	*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
891 
892 	return 0;
893 }
894 
895 static const struct irq_domain_ops partition_domain_ops = {
896 	.translate = partition_domain_translate,
897 	.select = gic_irq_domain_select,
898 };
899 
900 static void gicv3_enable_quirks(void)
901 {
902 #ifdef CONFIG_ARM64
903 	if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_23154))
904 		static_branch_enable(&is_cavium_thunderx);
905 #endif
906 }
907 
908 static int __init gic_init_bases(void __iomem *dist_base,
909 				 struct redist_region *rdist_regs,
910 				 u32 nr_redist_regions,
911 				 u64 redist_stride,
912 				 struct fwnode_handle *handle)
913 {
914 	struct device_node *node;
915 	u32 typer;
916 	int gic_irqs;
917 	int err;
918 
919 	if (!is_hyp_mode_available())
920 		static_key_slow_dec(&supports_deactivate);
921 
922 	if (static_key_true(&supports_deactivate))
923 		pr_info("GIC: Using split EOI/Deactivate mode\n");
924 
925 	gic_data.fwnode = handle;
926 	gic_data.dist_base = dist_base;
927 	gic_data.redist_regions = rdist_regs;
928 	gic_data.nr_redist_regions = nr_redist_regions;
929 	gic_data.redist_stride = redist_stride;
930 
931 	gicv3_enable_quirks();
932 
933 	/*
934 	 * Find out how many interrupts are supported.
935 	 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
936 	 */
937 	typer = readl_relaxed(gic_data.dist_base + GICD_TYPER);
938 	gic_data.rdists.id_bits = GICD_TYPER_ID_BITS(typer);
939 	gic_irqs = GICD_TYPER_IRQS(typer);
940 	if (gic_irqs > 1020)
941 		gic_irqs = 1020;
942 	gic_data.irq_nr = gic_irqs;
943 
944 	gic_data.domain = irq_domain_create_tree(handle, &gic_irq_domain_ops,
945 						 &gic_data);
946 	gic_data.rdists.rdist = alloc_percpu(typeof(*gic_data.rdists.rdist));
947 
948 	if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdists.rdist)) {
949 		err = -ENOMEM;
950 		goto out_free;
951 	}
952 
953 	set_handle_irq(gic_handle_irq);
954 
955 	node = to_of_node(handle);
956 	if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis() &&
957 	    node) /* Temp hack to prevent ITS init for ACPI */
958 		its_init(node, &gic_data.rdists, gic_data.domain);
959 
960 	gic_smp_init();
961 	gic_dist_init();
962 	gic_cpu_init();
963 	gic_cpu_pm_init();
964 
965 	return 0;
966 
967 out_free:
968 	if (gic_data.domain)
969 		irq_domain_remove(gic_data.domain);
970 	free_percpu(gic_data.rdists.rdist);
971 	return err;
972 }
973 
974 static int __init gic_validate_dist_version(void __iomem *dist_base)
975 {
976 	u32 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
977 
978 	if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4)
979 		return -ENODEV;
980 
981 	return 0;
982 }
983 
984 static int get_cpu_number(struct device_node *dn)
985 {
986 	const __be32 *cell;
987 	u64 hwid;
988 	int i;
989 
990 	cell = of_get_property(dn, "reg", NULL);
991 	if (!cell)
992 		return -1;
993 
994 	hwid = of_read_number(cell, of_n_addr_cells(dn));
995 
996 	/*
997 	 * Non affinity bits must be set to 0 in the DT
998 	 */
999 	if (hwid & ~MPIDR_HWID_BITMASK)
1000 		return -1;
1001 
1002 	for (i = 0; i < num_possible_cpus(); i++)
1003 		if (cpu_logical_map(i) == hwid)
1004 			return i;
1005 
1006 	return -1;
1007 }
1008 
1009 /* Create all possible partitions at boot time */
1010 static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
1011 {
1012 	struct device_node *parts_node, *child_part;
1013 	int part_idx = 0, i;
1014 	int nr_parts;
1015 	struct partition_affinity *parts;
1016 
1017 	parts_node = of_find_node_by_name(gic_node, "ppi-partitions");
1018 	if (!parts_node)
1019 		return;
1020 
1021 	nr_parts = of_get_child_count(parts_node);
1022 
1023 	if (!nr_parts)
1024 		return;
1025 
1026 	parts = kzalloc(sizeof(*parts) * nr_parts, GFP_KERNEL);
1027 	if (WARN_ON(!parts))
1028 		return;
1029 
1030 	for_each_child_of_node(parts_node, child_part) {
1031 		struct partition_affinity *part;
1032 		int n;
1033 
1034 		part = &parts[part_idx];
1035 
1036 		part->partition_id = of_node_to_fwnode(child_part);
1037 
1038 		pr_info("GIC: PPI partition %s[%d] { ",
1039 			child_part->name, part_idx);
1040 
1041 		n = of_property_count_elems_of_size(child_part, "affinity",
1042 						    sizeof(u32));
1043 		WARN_ON(n <= 0);
1044 
1045 		for (i = 0; i < n; i++) {
1046 			int err, cpu;
1047 			u32 cpu_phandle;
1048 			struct device_node *cpu_node;
1049 
1050 			err = of_property_read_u32_index(child_part, "affinity",
1051 							 i, &cpu_phandle);
1052 			if (WARN_ON(err))
1053 				continue;
1054 
1055 			cpu_node = of_find_node_by_phandle(cpu_phandle);
1056 			if (WARN_ON(!cpu_node))
1057 				continue;
1058 
1059 			cpu = get_cpu_number(cpu_node);
1060 			if (WARN_ON(cpu == -1))
1061 				continue;
1062 
1063 			pr_cont("%s[%d] ", cpu_node->full_name, cpu);
1064 
1065 			cpumask_set_cpu(cpu, &part->mask);
1066 		}
1067 
1068 		pr_cont("}\n");
1069 		part_idx++;
1070 	}
1071 
1072 	for (i = 0; i < 16; i++) {
1073 		unsigned int irq;
1074 		struct partition_desc *desc;
1075 		struct irq_fwspec ppi_fwspec = {
1076 			.fwnode		= gic_data.fwnode,
1077 			.param_count	= 3,
1078 			.param		= {
1079 				[0]	= 1,
1080 				[1]	= i,
1081 				[2]	= IRQ_TYPE_NONE,
1082 			},
1083 		};
1084 
1085 		irq = irq_create_fwspec_mapping(&ppi_fwspec);
1086 		if (WARN_ON(!irq))
1087 			continue;
1088 		desc = partition_create_desc(gic_data.fwnode, parts, nr_parts,
1089 					     irq, &partition_domain_ops);
1090 		if (WARN_ON(!desc))
1091 			continue;
1092 
1093 		gic_data.ppi_descs[i] = desc;
1094 	}
1095 }
1096 
1097 static void __init gic_of_setup_kvm_info(struct device_node *node)
1098 {
1099 	int ret;
1100 	struct resource r;
1101 	u32 gicv_idx;
1102 
1103 	gic_v3_kvm_info.type = GIC_V3;
1104 
1105 	gic_v3_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
1106 	if (!gic_v3_kvm_info.maint_irq)
1107 		return;
1108 
1109 	if (of_property_read_u32(node, "#redistributor-regions",
1110 				 &gicv_idx))
1111 		gicv_idx = 1;
1112 
1113 	gicv_idx += 3;	/* Also skip GICD, GICC, GICH */
1114 	ret = of_address_to_resource(node, gicv_idx, &r);
1115 	if (!ret)
1116 		gic_v3_kvm_info.vcpu = r;
1117 
1118 	gic_set_kvm_info(&gic_v3_kvm_info);
1119 }
1120 
1121 static int __init gic_of_init(struct device_node *node, struct device_node *parent)
1122 {
1123 	void __iomem *dist_base;
1124 	struct redist_region *rdist_regs;
1125 	u64 redist_stride;
1126 	u32 nr_redist_regions;
1127 	int err, i;
1128 
1129 	dist_base = of_iomap(node, 0);
1130 	if (!dist_base) {
1131 		pr_err("%s: unable to map gic dist registers\n",
1132 			node->full_name);
1133 		return -ENXIO;
1134 	}
1135 
1136 	err = gic_validate_dist_version(dist_base);
1137 	if (err) {
1138 		pr_err("%s: no distributor detected, giving up\n",
1139 			node->full_name);
1140 		goto out_unmap_dist;
1141 	}
1142 
1143 	if (of_property_read_u32(node, "#redistributor-regions", &nr_redist_regions))
1144 		nr_redist_regions = 1;
1145 
1146 	rdist_regs = kzalloc(sizeof(*rdist_regs) * nr_redist_regions, GFP_KERNEL);
1147 	if (!rdist_regs) {
1148 		err = -ENOMEM;
1149 		goto out_unmap_dist;
1150 	}
1151 
1152 	for (i = 0; i < nr_redist_regions; i++) {
1153 		struct resource res;
1154 		int ret;
1155 
1156 		ret = of_address_to_resource(node, 1 + i, &res);
1157 		rdist_regs[i].redist_base = of_iomap(node, 1 + i);
1158 		if (ret || !rdist_regs[i].redist_base) {
1159 			pr_err("%s: couldn't map region %d\n",
1160 			       node->full_name, i);
1161 			err = -ENODEV;
1162 			goto out_unmap_rdist;
1163 		}
1164 		rdist_regs[i].phys_base = res.start;
1165 	}
1166 
1167 	if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
1168 		redist_stride = 0;
1169 
1170 	err = gic_init_bases(dist_base, rdist_regs, nr_redist_regions,
1171 			     redist_stride, &node->fwnode);
1172 	if (err)
1173 		goto out_unmap_rdist;
1174 
1175 	gic_populate_ppi_partitions(node);
1176 	gic_of_setup_kvm_info(node);
1177 	return 0;
1178 
1179 out_unmap_rdist:
1180 	for (i = 0; i < nr_redist_regions; i++)
1181 		if (rdist_regs[i].redist_base)
1182 			iounmap(rdist_regs[i].redist_base);
1183 	kfree(rdist_regs);
1184 out_unmap_dist:
1185 	iounmap(dist_base);
1186 	return err;
1187 }
1188 
1189 IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);
1190 
1191 #ifdef CONFIG_ACPI
1192 static struct
1193 {
1194 	void __iomem *dist_base;
1195 	struct redist_region *redist_regs;
1196 	u32 nr_redist_regions;
1197 	bool single_redist;
1198 	u32 maint_irq;
1199 	int maint_irq_mode;
1200 	phys_addr_t vcpu_base;
1201 } acpi_data __initdata;
1202 
1203 static void __init
1204 gic_acpi_register_redist(phys_addr_t phys_base, void __iomem *redist_base)
1205 {
1206 	static int count = 0;
1207 
1208 	acpi_data.redist_regs[count].phys_base = phys_base;
1209 	acpi_data.redist_regs[count].redist_base = redist_base;
1210 	acpi_data.redist_regs[count].single_redist = acpi_data.single_redist;
1211 	count++;
1212 }
1213 
1214 static int __init
1215 gic_acpi_parse_madt_redist(struct acpi_subtable_header *header,
1216 			   const unsigned long end)
1217 {
1218 	struct acpi_madt_generic_redistributor *redist =
1219 			(struct acpi_madt_generic_redistributor *)header;
1220 	void __iomem *redist_base;
1221 
1222 	redist_base = ioremap(redist->base_address, redist->length);
1223 	if (!redist_base) {
1224 		pr_err("Couldn't map GICR region @%llx\n", redist->base_address);
1225 		return -ENOMEM;
1226 	}
1227 
1228 	gic_acpi_register_redist(redist->base_address, redist_base);
1229 	return 0;
1230 }
1231 
1232 static int __init
1233 gic_acpi_parse_madt_gicc(struct acpi_subtable_header *header,
1234 			 const unsigned long end)
1235 {
1236 	struct acpi_madt_generic_interrupt *gicc =
1237 				(struct acpi_madt_generic_interrupt *)header;
1238 	u32 reg = readl_relaxed(acpi_data.dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
1239 	u32 size = reg == GIC_PIDR2_ARCH_GICv4 ? SZ_64K * 4 : SZ_64K * 2;
1240 	void __iomem *redist_base;
1241 
1242 	redist_base = ioremap(gicc->gicr_base_address, size);
1243 	if (!redist_base)
1244 		return -ENOMEM;
1245 
1246 	gic_acpi_register_redist(gicc->gicr_base_address, redist_base);
1247 	return 0;
1248 }
1249 
1250 static int __init gic_acpi_collect_gicr_base(void)
1251 {
1252 	acpi_tbl_entry_handler redist_parser;
1253 	enum acpi_madt_type type;
1254 
1255 	if (acpi_data.single_redist) {
1256 		type = ACPI_MADT_TYPE_GENERIC_INTERRUPT;
1257 		redist_parser = gic_acpi_parse_madt_gicc;
1258 	} else {
1259 		type = ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR;
1260 		redist_parser = gic_acpi_parse_madt_redist;
1261 	}
1262 
1263 	/* Collect redistributor base addresses in GICR entries */
1264 	if (acpi_table_parse_madt(type, redist_parser, 0) > 0)
1265 		return 0;
1266 
1267 	pr_info("No valid GICR entries exist\n");
1268 	return -ENODEV;
1269 }
1270 
1271 static int __init gic_acpi_match_gicr(struct acpi_subtable_header *header,
1272 				  const unsigned long end)
1273 {
1274 	/* Subtable presence means that redist exists, that's it */
1275 	return 0;
1276 }
1277 
1278 static int __init gic_acpi_match_gicc(struct acpi_subtable_header *header,
1279 				      const unsigned long end)
1280 {
1281 	struct acpi_madt_generic_interrupt *gicc =
1282 				(struct acpi_madt_generic_interrupt *)header;
1283 
1284 	/*
1285 	 * If GICC is enabled and has valid gicr base address, then it means
1286 	 * GICR base is presented via GICC
1287 	 */
1288 	if ((gicc->flags & ACPI_MADT_ENABLED) && gicc->gicr_base_address)
1289 		return 0;
1290 
1291 	return -ENODEV;
1292 }
1293 
1294 static int __init gic_acpi_count_gicr_regions(void)
1295 {
1296 	int count;
1297 
1298 	/*
1299 	 * Count how many redistributor regions we have. It is not allowed
1300 	 * to mix redistributor description, GICR and GICC subtables have to be
1301 	 * mutually exclusive.
1302 	 */
1303 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
1304 				      gic_acpi_match_gicr, 0);
1305 	if (count > 0) {
1306 		acpi_data.single_redist = false;
1307 		return count;
1308 	}
1309 
1310 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1311 				      gic_acpi_match_gicc, 0);
1312 	if (count > 0)
1313 		acpi_data.single_redist = true;
1314 
1315 	return count;
1316 }
1317 
1318 static bool __init acpi_validate_gic_table(struct acpi_subtable_header *header,
1319 					   struct acpi_probe_entry *ape)
1320 {
1321 	struct acpi_madt_generic_distributor *dist;
1322 	int count;
1323 
1324 	dist = (struct acpi_madt_generic_distributor *)header;
1325 	if (dist->version != ape->driver_data)
1326 		return false;
1327 
1328 	/* We need to do that exercise anyway, the sooner the better */
1329 	count = gic_acpi_count_gicr_regions();
1330 	if (count <= 0)
1331 		return false;
1332 
1333 	acpi_data.nr_redist_regions = count;
1334 	return true;
1335 }
1336 
1337 static int __init gic_acpi_parse_virt_madt_gicc(struct acpi_subtable_header *header,
1338 						const unsigned long end)
1339 {
1340 	struct acpi_madt_generic_interrupt *gicc =
1341 		(struct acpi_madt_generic_interrupt *)header;
1342 	int maint_irq_mode;
1343 	static int first_madt = true;
1344 
1345 	/* Skip unusable CPUs */
1346 	if (!(gicc->flags & ACPI_MADT_ENABLED))
1347 		return 0;
1348 
1349 	maint_irq_mode = (gicc->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
1350 		ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
1351 
1352 	if (first_madt) {
1353 		first_madt = false;
1354 
1355 		acpi_data.maint_irq = gicc->vgic_interrupt;
1356 		acpi_data.maint_irq_mode = maint_irq_mode;
1357 		acpi_data.vcpu_base = gicc->gicv_base_address;
1358 
1359 		return 0;
1360 	}
1361 
1362 	/*
1363 	 * The maintenance interrupt and GICV should be the same for every CPU
1364 	 */
1365 	if ((acpi_data.maint_irq != gicc->vgic_interrupt) ||
1366 	    (acpi_data.maint_irq_mode != maint_irq_mode) ||
1367 	    (acpi_data.vcpu_base != gicc->gicv_base_address))
1368 		return -EINVAL;
1369 
1370 	return 0;
1371 }
1372 
1373 static bool __init gic_acpi_collect_virt_info(void)
1374 {
1375 	int count;
1376 
1377 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1378 				      gic_acpi_parse_virt_madt_gicc, 0);
1379 
1380 	return (count > 0);
1381 }
1382 
1383 #define ACPI_GICV3_DIST_MEM_SIZE (SZ_64K)
1384 #define ACPI_GICV2_VCTRL_MEM_SIZE	(SZ_4K)
1385 #define ACPI_GICV2_VCPU_MEM_SIZE	(SZ_8K)
1386 
1387 static void __init gic_acpi_setup_kvm_info(void)
1388 {
1389 	int irq;
1390 
1391 	if (!gic_acpi_collect_virt_info()) {
1392 		pr_warn("Unable to get hardware information used for virtualization\n");
1393 		return;
1394 	}
1395 
1396 	gic_v3_kvm_info.type = GIC_V3;
1397 
1398 	irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
1399 				acpi_data.maint_irq_mode,
1400 				ACPI_ACTIVE_HIGH);
1401 	if (irq <= 0)
1402 		return;
1403 
1404 	gic_v3_kvm_info.maint_irq = irq;
1405 
1406 	if (acpi_data.vcpu_base) {
1407 		struct resource *vcpu = &gic_v3_kvm_info.vcpu;
1408 
1409 		vcpu->flags = IORESOURCE_MEM;
1410 		vcpu->start = acpi_data.vcpu_base;
1411 		vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
1412 	}
1413 
1414 	gic_set_kvm_info(&gic_v3_kvm_info);
1415 }
1416 
1417 static int __init
1418 gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
1419 {
1420 	struct acpi_madt_generic_distributor *dist;
1421 	struct fwnode_handle *domain_handle;
1422 	size_t size;
1423 	int i, err;
1424 
1425 	/* Get distributor base address */
1426 	dist = (struct acpi_madt_generic_distributor *)header;
1427 	acpi_data.dist_base = ioremap(dist->base_address,
1428 				      ACPI_GICV3_DIST_MEM_SIZE);
1429 	if (!acpi_data.dist_base) {
1430 		pr_err("Unable to map GICD registers\n");
1431 		return -ENOMEM;
1432 	}
1433 
1434 	err = gic_validate_dist_version(acpi_data.dist_base);
1435 	if (err) {
1436 		pr_err("No distributor detected at @%p, giving up",
1437 		       acpi_data.dist_base);
1438 		goto out_dist_unmap;
1439 	}
1440 
1441 	size = sizeof(*acpi_data.redist_regs) * acpi_data.nr_redist_regions;
1442 	acpi_data.redist_regs = kzalloc(size, GFP_KERNEL);
1443 	if (!acpi_data.redist_regs) {
1444 		err = -ENOMEM;
1445 		goto out_dist_unmap;
1446 	}
1447 
1448 	err = gic_acpi_collect_gicr_base();
1449 	if (err)
1450 		goto out_redist_unmap;
1451 
1452 	domain_handle = irq_domain_alloc_fwnode(acpi_data.dist_base);
1453 	if (!domain_handle) {
1454 		err = -ENOMEM;
1455 		goto out_redist_unmap;
1456 	}
1457 
1458 	err = gic_init_bases(acpi_data.dist_base, acpi_data.redist_regs,
1459 			     acpi_data.nr_redist_regions, 0, domain_handle);
1460 	if (err)
1461 		goto out_fwhandle_free;
1462 
1463 	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
1464 	gic_acpi_setup_kvm_info();
1465 
1466 	return 0;
1467 
1468 out_fwhandle_free:
1469 	irq_domain_free_fwnode(domain_handle);
1470 out_redist_unmap:
1471 	for (i = 0; i < acpi_data.nr_redist_regions; i++)
1472 		if (acpi_data.redist_regs[i].redist_base)
1473 			iounmap(acpi_data.redist_regs[i].redist_base);
1474 	kfree(acpi_data.redist_regs);
1475 out_dist_unmap:
1476 	iounmap(acpi_data.dist_base);
1477 	return err;
1478 }
1479 IRQCHIP_ACPI_DECLARE(gic_v3, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1480 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V3,
1481 		     gic_acpi_init);
1482 IRQCHIP_ACPI_DECLARE(gic_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1483 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_V4,
1484 		     gic_acpi_init);
1485 IRQCHIP_ACPI_DECLARE(gic_v3_or_v4, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1486 		     acpi_validate_gic_table, ACPI_MADT_GIC_VERSION_NONE,
1487 		     gic_acpi_init);
1488 #endif
1489