xref: /openbmc/linux/drivers/irqchip/irq-gic.c (revision fc772314)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2002 ARM Limited, All Rights Reserved.
4  *
5  * Interrupt architecture for the GIC:
6  *
7  * o There is one Interrupt Distributor, which receives interrupts
8  *   from system devices and sends them to the Interrupt Controllers.
9  *
10  * o There is one CPU Interface per CPU, which sends interrupts sent
11  *   by the Distributor, and interrupts generated locally, to the
12  *   associated CPU. The base address of the CPU interface is usually
13  *   aliased so that the same address points to different chips depending
14  *   on the CPU it is accessed from.
15  *
16  * Note that IRQs 0-31 are special - they are local to each CPU.
17  * As such, the enable set/clear, pending set/clear and active bit
18  * registers are banked per-cpu for these sources.
19  */
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/err.h>
23 #include <linux/module.h>
24 #include <linux/list.h>
25 #include <linux/smp.h>
26 #include <linux/cpu.h>
27 #include <linux/cpu_pm.h>
28 #include <linux/cpumask.h>
29 #include <linux/io.h>
30 #include <linux/of.h>
31 #include <linux/of_address.h>
32 #include <linux/of_irq.h>
33 #include <linux/acpi.h>
34 #include <linux/irqdomain.h>
35 #include <linux/interrupt.h>
36 #include <linux/percpu.h>
37 #include <linux/slab.h>
38 #include <linux/irqchip.h>
39 #include <linux/irqchip/chained_irq.h>
40 #include <linux/irqchip/arm-gic.h>
41 
42 #include <asm/cputype.h>
43 #include <asm/irq.h>
44 #include <asm/exception.h>
45 #include <asm/smp_plat.h>
46 #include <asm/virt.h>
47 
48 #include "irq-gic-common.h"
49 
50 #ifdef CONFIG_ARM64
51 #include <asm/cpufeature.h>
52 
53 static void gic_check_cpu_features(void)
54 {
55 	WARN_TAINT_ONCE(this_cpu_has_cap(ARM64_HAS_SYSREG_GIC_CPUIF),
56 			TAINT_CPU_OUT_OF_SPEC,
57 			"GICv3 system registers enabled, broken firmware!\n");
58 }
59 #else
60 #define gic_check_cpu_features()	do { } while(0)
61 #endif
62 
63 union gic_base {
64 	void __iomem *common_base;
65 	void __percpu * __iomem *percpu_base;
66 };
67 
68 struct gic_chip_data {
69 	struct irq_chip chip;
70 	union gic_base dist_base;
71 	union gic_base cpu_base;
72 	void __iomem *raw_dist_base;
73 	void __iomem *raw_cpu_base;
74 	u32 percpu_offset;
75 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
76 	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
77 	u32 saved_spi_active[DIV_ROUND_UP(1020, 32)];
78 	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
79 	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
80 	u32 __percpu *saved_ppi_enable;
81 	u32 __percpu *saved_ppi_active;
82 	u32 __percpu *saved_ppi_conf;
83 #endif
84 	struct irq_domain *domain;
85 	unsigned int gic_irqs;
86 #ifdef CONFIG_GIC_NON_BANKED
87 	void __iomem *(*get_base)(union gic_base *);
88 #endif
89 };
90 
91 #ifdef CONFIG_BL_SWITCHER
92 
93 static DEFINE_RAW_SPINLOCK(cpu_map_lock);
94 
95 #define gic_lock_irqsave(f)		\
96 	raw_spin_lock_irqsave(&cpu_map_lock, (f))
97 #define gic_unlock_irqrestore(f)	\
98 	raw_spin_unlock_irqrestore(&cpu_map_lock, (f))
99 
100 #define gic_lock()			raw_spin_lock(&cpu_map_lock)
101 #define gic_unlock()			raw_spin_unlock(&cpu_map_lock)
102 
103 #else
104 
105 #define gic_lock_irqsave(f)		do { (void)(f); } while(0)
106 #define gic_unlock_irqrestore(f)	do { (void)(f); } while(0)
107 
108 #define gic_lock()			do { } while(0)
109 #define gic_unlock()			do { } while(0)
110 
111 #endif
112 
113 /*
114  * The GIC mapping of CPU interfaces does not necessarily match
115  * the logical CPU numbering.  Let's use a mapping as returned
116  * by the GIC itself.
117  */
118 #define NR_GIC_CPU_IF 8
119 static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
120 
121 static DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
122 
123 static struct gic_chip_data gic_data[CONFIG_ARM_GIC_MAX_NR] __read_mostly;
124 
125 static struct gic_kvm_info gic_v2_kvm_info;
126 
127 #ifdef CONFIG_GIC_NON_BANKED
128 static void __iomem *gic_get_percpu_base(union gic_base *base)
129 {
130 	return raw_cpu_read(*base->percpu_base);
131 }
132 
133 static void __iomem *gic_get_common_base(union gic_base *base)
134 {
135 	return base->common_base;
136 }
137 
138 static inline void __iomem *gic_data_dist_base(struct gic_chip_data *data)
139 {
140 	return data->get_base(&data->dist_base);
141 }
142 
143 static inline void __iomem *gic_data_cpu_base(struct gic_chip_data *data)
144 {
145 	return data->get_base(&data->cpu_base);
146 }
147 
148 static inline void gic_set_base_accessor(struct gic_chip_data *data,
149 					 void __iomem *(*f)(union gic_base *))
150 {
151 	data->get_base = f;
152 }
153 #else
154 #define gic_data_dist_base(d)	((d)->dist_base.common_base)
155 #define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
156 #define gic_set_base_accessor(d, f)
157 #endif
158 
159 static inline void __iomem *gic_dist_base(struct irq_data *d)
160 {
161 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
162 	return gic_data_dist_base(gic_data);
163 }
164 
165 static inline void __iomem *gic_cpu_base(struct irq_data *d)
166 {
167 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
168 	return gic_data_cpu_base(gic_data);
169 }
170 
171 static inline unsigned int gic_irq(struct irq_data *d)
172 {
173 	return d->hwirq;
174 }
175 
176 static inline bool cascading_gic_irq(struct irq_data *d)
177 {
178 	void *data = irq_data_get_irq_handler_data(d);
179 
180 	/*
181 	 * If handler_data is set, this is a cascading interrupt, and
182 	 * it cannot possibly be forwarded.
183 	 */
184 	return data != NULL;
185 }
186 
187 /*
188  * Routines to acknowledge, disable and enable interrupts
189  */
190 static void gic_poke_irq(struct irq_data *d, u32 offset)
191 {
192 	u32 mask = 1 << (gic_irq(d) % 32);
193 	writel_relaxed(mask, gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4);
194 }
195 
196 static int gic_peek_irq(struct irq_data *d, u32 offset)
197 {
198 	u32 mask = 1 << (gic_irq(d) % 32);
199 	return !!(readl_relaxed(gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4) & mask);
200 }
201 
202 static void gic_mask_irq(struct irq_data *d)
203 {
204 	gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
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, GIC_DIST_ACTIVE_CLEAR);
220 }
221 
222 static void gic_unmask_irq(struct irq_data *d)
223 {
224 	gic_poke_irq(d, GIC_DIST_ENABLE_SET);
225 }
226 
227 static void gic_eoi_irq(struct irq_data *d)
228 {
229 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
230 }
231 
232 static void gic_eoimode1_eoi_irq(struct irq_data *d)
233 {
234 	/* Do not deactivate an IRQ forwarded to a vcpu. */
235 	if (irqd_is_forwarded_to_vcpu(d))
236 		return;
237 
238 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_DEACTIVATE);
239 }
240 
241 static int gic_irq_set_irqchip_state(struct irq_data *d,
242 				     enum irqchip_irq_state which, bool val)
243 {
244 	u32 reg;
245 
246 	switch (which) {
247 	case IRQCHIP_STATE_PENDING:
248 		reg = val ? GIC_DIST_PENDING_SET : GIC_DIST_PENDING_CLEAR;
249 		break;
250 
251 	case IRQCHIP_STATE_ACTIVE:
252 		reg = val ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR;
253 		break;
254 
255 	case IRQCHIP_STATE_MASKED:
256 		reg = val ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET;
257 		break;
258 
259 	default:
260 		return -EINVAL;
261 	}
262 
263 	gic_poke_irq(d, reg);
264 	return 0;
265 }
266 
267 static int gic_irq_get_irqchip_state(struct irq_data *d,
268 				      enum irqchip_irq_state which, bool *val)
269 {
270 	switch (which) {
271 	case IRQCHIP_STATE_PENDING:
272 		*val = gic_peek_irq(d, GIC_DIST_PENDING_SET);
273 		break;
274 
275 	case IRQCHIP_STATE_ACTIVE:
276 		*val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET);
277 		break;
278 
279 	case IRQCHIP_STATE_MASKED:
280 		*val = !gic_peek_irq(d, GIC_DIST_ENABLE_SET);
281 		break;
282 
283 	default:
284 		return -EINVAL;
285 	}
286 
287 	return 0;
288 }
289 
290 static int gic_set_type(struct irq_data *d, unsigned int type)
291 {
292 	void __iomem *base = gic_dist_base(d);
293 	unsigned int gicirq = gic_irq(d);
294 	int ret;
295 
296 	/* Interrupt configuration for SGIs can't be changed */
297 	if (gicirq < 16)
298 		return -EINVAL;
299 
300 	/* SPIs have restrictions on the supported types */
301 	if (gicirq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
302 			    type != IRQ_TYPE_EDGE_RISING)
303 		return -EINVAL;
304 
305 	ret = gic_configure_irq(gicirq, type, base + GIC_DIST_CONFIG, NULL);
306 	if (ret && gicirq < 32) {
307 		/* Misconfigured PPIs are usually not fatal */
308 		pr_warn("GIC: PPI%d is secure or misconfigured\n", gicirq - 16);
309 		ret = 0;
310 	}
311 
312 	return ret;
313 }
314 
315 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
316 {
317 	/* Only interrupts on the primary GIC can be forwarded to a vcpu. */
318 	if (cascading_gic_irq(d))
319 		return -EINVAL;
320 
321 	if (vcpu)
322 		irqd_set_forwarded_to_vcpu(d);
323 	else
324 		irqd_clr_forwarded_to_vcpu(d);
325 	return 0;
326 }
327 
328 #ifdef CONFIG_SMP
329 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
330 			    bool force)
331 {
332 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + gic_irq(d);
333 	unsigned int cpu;
334 
335 	if (!force)
336 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
337 	else
338 		cpu = cpumask_first(mask_val);
339 
340 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
341 		return -EINVAL;
342 
343 	writeb_relaxed(gic_cpu_map[cpu], reg);
344 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
345 
346 	return IRQ_SET_MASK_OK_DONE;
347 }
348 #endif
349 
350 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
351 {
352 	u32 irqstat, irqnr;
353 	struct gic_chip_data *gic = &gic_data[0];
354 	void __iomem *cpu_base = gic_data_cpu_base(gic);
355 
356 	do {
357 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
358 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
359 
360 		if (likely(irqnr > 15 && irqnr < 1020)) {
361 			if (static_branch_likely(&supports_deactivate_key))
362 				writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
363 			isb();
364 			handle_domain_irq(gic->domain, irqnr, regs);
365 			continue;
366 		}
367 		if (irqnr < 16) {
368 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
369 			if (static_branch_likely(&supports_deactivate_key))
370 				writel_relaxed(irqstat, cpu_base + GIC_CPU_DEACTIVATE);
371 #ifdef CONFIG_SMP
372 			/*
373 			 * Ensure any shared data written by the CPU sending
374 			 * the IPI is read after we've read the ACK register
375 			 * on the GIC.
376 			 *
377 			 * Pairs with the write barrier in gic_raise_softirq
378 			 */
379 			smp_rmb();
380 			handle_IPI(irqnr, regs);
381 #endif
382 			continue;
383 		}
384 		break;
385 	} while (1);
386 }
387 
388 static void gic_handle_cascade_irq(struct irq_desc *desc)
389 {
390 	struct gic_chip_data *chip_data = irq_desc_get_handler_data(desc);
391 	struct irq_chip *chip = irq_desc_get_chip(desc);
392 	unsigned int cascade_irq, gic_irq;
393 	unsigned long status;
394 
395 	chained_irq_enter(chip, desc);
396 
397 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
398 
399 	gic_irq = (status & GICC_IAR_INT_ID_MASK);
400 	if (gic_irq == GICC_INT_SPURIOUS)
401 		goto out;
402 
403 	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
404 	if (unlikely(gic_irq < 32 || gic_irq > 1020)) {
405 		handle_bad_irq(desc);
406 	} else {
407 		isb();
408 		generic_handle_irq(cascade_irq);
409 	}
410 
411  out:
412 	chained_irq_exit(chip, desc);
413 }
414 
415 static const struct irq_chip gic_chip = {
416 	.irq_mask		= gic_mask_irq,
417 	.irq_unmask		= gic_unmask_irq,
418 	.irq_eoi		= gic_eoi_irq,
419 	.irq_set_type		= gic_set_type,
420 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
421 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
422 	.flags			= IRQCHIP_SET_TYPE_MASKED |
423 				  IRQCHIP_SKIP_SET_WAKE |
424 				  IRQCHIP_MASK_ON_SUSPEND,
425 };
426 
427 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
428 {
429 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
430 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq,
431 					 &gic_data[gic_nr]);
432 }
433 
434 static u8 gic_get_cpumask(struct gic_chip_data *gic)
435 {
436 	void __iomem *base = gic_data_dist_base(gic);
437 	u32 mask, i;
438 
439 	for (i = mask = 0; i < 32; i += 4) {
440 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
441 		mask |= mask >> 16;
442 		mask |= mask >> 8;
443 		if (mask)
444 			break;
445 	}
446 
447 	if (!mask && num_possible_cpus() > 1)
448 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
449 
450 	return mask;
451 }
452 
453 static bool gic_check_gicv2(void __iomem *base)
454 {
455 	u32 val = readl_relaxed(base + GIC_CPU_IDENT);
456 	return (val & 0xff0fff) == 0x02043B;
457 }
458 
459 static void gic_cpu_if_up(struct gic_chip_data *gic)
460 {
461 	void __iomem *cpu_base = gic_data_cpu_base(gic);
462 	u32 bypass = 0;
463 	u32 mode = 0;
464 	int i;
465 
466 	if (gic == &gic_data[0] && static_branch_likely(&supports_deactivate_key))
467 		mode = GIC_CPU_CTRL_EOImodeNS;
468 
469 	if (gic_check_gicv2(cpu_base))
470 		for (i = 0; i < 4; i++)
471 			writel_relaxed(0, cpu_base + GIC_CPU_ACTIVEPRIO + i * 4);
472 
473 	/*
474 	* Preserve bypass disable bits to be written back later
475 	*/
476 	bypass = readl(cpu_base + GIC_CPU_CTRL);
477 	bypass &= GICC_DIS_BYPASS_MASK;
478 
479 	writel_relaxed(bypass | mode | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
480 }
481 
482 
483 static void gic_dist_init(struct gic_chip_data *gic)
484 {
485 	unsigned int i;
486 	u32 cpumask;
487 	unsigned int gic_irqs = gic->gic_irqs;
488 	void __iomem *base = gic_data_dist_base(gic);
489 
490 	writel_relaxed(GICD_DISABLE, base + GIC_DIST_CTRL);
491 
492 	/*
493 	 * Set all global interrupts to this CPU only.
494 	 */
495 	cpumask = gic_get_cpumask(gic);
496 	cpumask |= cpumask << 8;
497 	cpumask |= cpumask << 16;
498 	for (i = 32; i < gic_irqs; i += 4)
499 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
500 
501 	gic_dist_config(base, gic_irqs, NULL);
502 
503 	writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL);
504 }
505 
506 static int gic_cpu_init(struct gic_chip_data *gic)
507 {
508 	void __iomem *dist_base = gic_data_dist_base(gic);
509 	void __iomem *base = gic_data_cpu_base(gic);
510 	unsigned int cpu_mask, cpu = smp_processor_id();
511 	int i;
512 
513 	/*
514 	 * Setting up the CPU map is only relevant for the primary GIC
515 	 * because any nested/secondary GICs do not directly interface
516 	 * with the CPU(s).
517 	 */
518 	if (gic == &gic_data[0]) {
519 		/*
520 		 * Get what the GIC says our CPU mask is.
521 		 */
522 		if (WARN_ON(cpu >= NR_GIC_CPU_IF))
523 			return -EINVAL;
524 
525 		gic_check_cpu_features();
526 		cpu_mask = gic_get_cpumask(gic);
527 		gic_cpu_map[cpu] = cpu_mask;
528 
529 		/*
530 		 * Clear our mask from the other map entries in case they're
531 		 * still undefined.
532 		 */
533 		for (i = 0; i < NR_GIC_CPU_IF; i++)
534 			if (i != cpu)
535 				gic_cpu_map[i] &= ~cpu_mask;
536 	}
537 
538 	gic_cpu_config(dist_base, 32, NULL);
539 
540 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
541 	gic_cpu_if_up(gic);
542 
543 	return 0;
544 }
545 
546 int gic_cpu_if_down(unsigned int gic_nr)
547 {
548 	void __iomem *cpu_base;
549 	u32 val = 0;
550 
551 	if (gic_nr >= CONFIG_ARM_GIC_MAX_NR)
552 		return -EINVAL;
553 
554 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
555 	val = readl(cpu_base + GIC_CPU_CTRL);
556 	val &= ~GICC_ENABLE;
557 	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
558 
559 	return 0;
560 }
561 
562 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
563 /*
564  * Saves the GIC distributor registers during suspend or idle.  Must be called
565  * with interrupts disabled but before powering down the GIC.  After calling
566  * this function, no interrupts will be delivered by the GIC, and another
567  * platform-specific wakeup source must be enabled.
568  */
569 void gic_dist_save(struct gic_chip_data *gic)
570 {
571 	unsigned int gic_irqs;
572 	void __iomem *dist_base;
573 	int i;
574 
575 	if (WARN_ON(!gic))
576 		return;
577 
578 	gic_irqs = gic->gic_irqs;
579 	dist_base = gic_data_dist_base(gic);
580 
581 	if (!dist_base)
582 		return;
583 
584 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
585 		gic->saved_spi_conf[i] =
586 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
587 
588 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
589 		gic->saved_spi_target[i] =
590 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
591 
592 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
593 		gic->saved_spi_enable[i] =
594 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
595 
596 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
597 		gic->saved_spi_active[i] =
598 			readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
599 }
600 
601 /*
602  * Restores the GIC distributor registers during resume or when coming out of
603  * idle.  Must be called before enabling interrupts.  If a level interrupt
604  * that occurred while the GIC was suspended is still present, it will be
605  * handled normally, but any edge interrupts that occurred will not be seen by
606  * the GIC and need to be handled by the platform-specific wakeup source.
607  */
608 void gic_dist_restore(struct gic_chip_data *gic)
609 {
610 	unsigned int gic_irqs;
611 	unsigned int i;
612 	void __iomem *dist_base;
613 
614 	if (WARN_ON(!gic))
615 		return;
616 
617 	gic_irqs = gic->gic_irqs;
618 	dist_base = gic_data_dist_base(gic);
619 
620 	if (!dist_base)
621 		return;
622 
623 	writel_relaxed(GICD_DISABLE, dist_base + GIC_DIST_CTRL);
624 
625 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
626 		writel_relaxed(gic->saved_spi_conf[i],
627 			dist_base + GIC_DIST_CONFIG + i * 4);
628 
629 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
630 		writel_relaxed(GICD_INT_DEF_PRI_X4,
631 			dist_base + GIC_DIST_PRI + i * 4);
632 
633 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
634 		writel_relaxed(gic->saved_spi_target[i],
635 			dist_base + GIC_DIST_TARGET + i * 4);
636 
637 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
638 		writel_relaxed(GICD_INT_EN_CLR_X32,
639 			dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
640 		writel_relaxed(gic->saved_spi_enable[i],
641 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
642 	}
643 
644 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
645 		writel_relaxed(GICD_INT_EN_CLR_X32,
646 			dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
647 		writel_relaxed(gic->saved_spi_active[i],
648 			dist_base + GIC_DIST_ACTIVE_SET + i * 4);
649 	}
650 
651 	writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL);
652 }
653 
654 void gic_cpu_save(struct gic_chip_data *gic)
655 {
656 	int i;
657 	u32 *ptr;
658 	void __iomem *dist_base;
659 	void __iomem *cpu_base;
660 
661 	if (WARN_ON(!gic))
662 		return;
663 
664 	dist_base = gic_data_dist_base(gic);
665 	cpu_base = gic_data_cpu_base(gic);
666 
667 	if (!dist_base || !cpu_base)
668 		return;
669 
670 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
671 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
672 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
673 
674 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
675 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
676 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
677 
678 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
679 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
680 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
681 
682 }
683 
684 void gic_cpu_restore(struct gic_chip_data *gic)
685 {
686 	int i;
687 	u32 *ptr;
688 	void __iomem *dist_base;
689 	void __iomem *cpu_base;
690 
691 	if (WARN_ON(!gic))
692 		return;
693 
694 	dist_base = gic_data_dist_base(gic);
695 	cpu_base = gic_data_cpu_base(gic);
696 
697 	if (!dist_base || !cpu_base)
698 		return;
699 
700 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
701 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
702 		writel_relaxed(GICD_INT_EN_CLR_X32,
703 			       dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
704 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
705 	}
706 
707 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
708 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
709 		writel_relaxed(GICD_INT_EN_CLR_X32,
710 			       dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
711 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ACTIVE_SET + i * 4);
712 	}
713 
714 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
715 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
716 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
717 
718 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
719 		writel_relaxed(GICD_INT_DEF_PRI_X4,
720 					dist_base + GIC_DIST_PRI + i * 4);
721 
722 	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
723 	gic_cpu_if_up(gic);
724 }
725 
726 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
727 {
728 	int i;
729 
730 	for (i = 0; i < CONFIG_ARM_GIC_MAX_NR; i++) {
731 #ifdef CONFIG_GIC_NON_BANKED
732 		/* Skip over unused GICs */
733 		if (!gic_data[i].get_base)
734 			continue;
735 #endif
736 		switch (cmd) {
737 		case CPU_PM_ENTER:
738 			gic_cpu_save(&gic_data[i]);
739 			break;
740 		case CPU_PM_ENTER_FAILED:
741 		case CPU_PM_EXIT:
742 			gic_cpu_restore(&gic_data[i]);
743 			break;
744 		case CPU_CLUSTER_PM_ENTER:
745 			gic_dist_save(&gic_data[i]);
746 			break;
747 		case CPU_CLUSTER_PM_ENTER_FAILED:
748 		case CPU_CLUSTER_PM_EXIT:
749 			gic_dist_restore(&gic_data[i]);
750 			break;
751 		}
752 	}
753 
754 	return NOTIFY_OK;
755 }
756 
757 static struct notifier_block gic_notifier_block = {
758 	.notifier_call = gic_notifier,
759 };
760 
761 static int gic_pm_init(struct gic_chip_data *gic)
762 {
763 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
764 		sizeof(u32));
765 	if (WARN_ON(!gic->saved_ppi_enable))
766 		return -ENOMEM;
767 
768 	gic->saved_ppi_active = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
769 		sizeof(u32));
770 	if (WARN_ON(!gic->saved_ppi_active))
771 		goto free_ppi_enable;
772 
773 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
774 		sizeof(u32));
775 	if (WARN_ON(!gic->saved_ppi_conf))
776 		goto free_ppi_active;
777 
778 	if (gic == &gic_data[0])
779 		cpu_pm_register_notifier(&gic_notifier_block);
780 
781 	return 0;
782 
783 free_ppi_active:
784 	free_percpu(gic->saved_ppi_active);
785 free_ppi_enable:
786 	free_percpu(gic->saved_ppi_enable);
787 
788 	return -ENOMEM;
789 }
790 #else
791 static int gic_pm_init(struct gic_chip_data *gic)
792 {
793 	return 0;
794 }
795 #endif
796 
797 #ifdef CONFIG_SMP
798 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
799 {
800 	int cpu;
801 	unsigned long flags, map = 0;
802 
803 	if (unlikely(nr_cpu_ids == 1)) {
804 		/* Only one CPU? let's do a self-IPI... */
805 		writel_relaxed(2 << 24 | irq,
806 			       gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
807 		return;
808 	}
809 
810 	gic_lock_irqsave(flags);
811 
812 	/* Convert our logical CPU mask into a physical one. */
813 	for_each_cpu(cpu, mask)
814 		map |= gic_cpu_map[cpu];
815 
816 	/*
817 	 * Ensure that stores to Normal memory are visible to the
818 	 * other CPUs before they observe us issuing the IPI.
819 	 */
820 	dmb(ishst);
821 
822 	/* this always happens on GIC0 */
823 	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
824 
825 	gic_unlock_irqrestore(flags);
826 }
827 #endif
828 
829 #ifdef CONFIG_BL_SWITCHER
830 /*
831  * gic_send_sgi - send a SGI directly to given CPU interface number
832  *
833  * cpu_id: the ID for the destination CPU interface
834  * irq: the IPI number to send a SGI for
835  */
836 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
837 {
838 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
839 	cpu_id = 1 << cpu_id;
840 	/* this always happens on GIC0 */
841 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
842 }
843 
844 /*
845  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
846  *
847  * @cpu: the logical CPU number to get the GIC ID for.
848  *
849  * Return the CPU interface ID for the given logical CPU number,
850  * or -1 if the CPU number is too large or the interface ID is
851  * unknown (more than one bit set).
852  */
853 int gic_get_cpu_id(unsigned int cpu)
854 {
855 	unsigned int cpu_bit;
856 
857 	if (cpu >= NR_GIC_CPU_IF)
858 		return -1;
859 	cpu_bit = gic_cpu_map[cpu];
860 	if (cpu_bit & (cpu_bit - 1))
861 		return -1;
862 	return __ffs(cpu_bit);
863 }
864 
865 /*
866  * gic_migrate_target - migrate IRQs to another CPU interface
867  *
868  * @new_cpu_id: the CPU target ID to migrate IRQs to
869  *
870  * Migrate all peripheral interrupts with a target matching the current CPU
871  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
872  * is also updated.  Targets to other CPU interfaces are unchanged.
873  * This must be called with IRQs locally disabled.
874  */
875 void gic_migrate_target(unsigned int new_cpu_id)
876 {
877 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
878 	void __iomem *dist_base;
879 	int i, ror_val, cpu = smp_processor_id();
880 	u32 val, cur_target_mask, active_mask;
881 
882 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
883 
884 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
885 	if (!dist_base)
886 		return;
887 	gic_irqs = gic_data[gic_nr].gic_irqs;
888 
889 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
890 	cur_target_mask = 0x01010101 << cur_cpu_id;
891 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
892 
893 	gic_lock();
894 
895 	/* Update the target interface for this logical CPU */
896 	gic_cpu_map[cpu] = 1 << new_cpu_id;
897 
898 	/*
899 	 * Find all the peripheral interrupts targeting the current
900 	 * CPU interface and migrate them to the new CPU interface.
901 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
902 	 */
903 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
904 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
905 		active_mask = val & cur_target_mask;
906 		if (active_mask) {
907 			val &= ~active_mask;
908 			val |= ror32(active_mask, ror_val);
909 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
910 		}
911 	}
912 
913 	gic_unlock();
914 
915 	/*
916 	 * Now let's migrate and clear any potential SGIs that might be
917 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
918 	 * is a banked register, we can only forward the SGI using
919 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
920 	 * doesn't use that information anyway.
921 	 *
922 	 * For the same reason we do not adjust SGI source information
923 	 * for previously sent SGIs by us to other CPUs either.
924 	 */
925 	for (i = 0; i < 16; i += 4) {
926 		int j;
927 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
928 		if (!val)
929 			continue;
930 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
931 		for (j = i; j < i + 4; j++) {
932 			if (val & 0xff)
933 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
934 						dist_base + GIC_DIST_SOFTINT);
935 			val >>= 8;
936 		}
937 	}
938 }
939 
940 /*
941  * gic_get_sgir_physaddr - get the physical address for the SGI register
942  *
943  * REturn the physical address of the SGI register to be used
944  * by some early assembly code when the kernel is not yet available.
945  */
946 static unsigned long gic_dist_physaddr;
947 
948 unsigned long gic_get_sgir_physaddr(void)
949 {
950 	if (!gic_dist_physaddr)
951 		return 0;
952 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
953 }
954 
955 static void __init gic_init_physaddr(struct device_node *node)
956 {
957 	struct resource res;
958 	if (of_address_to_resource(node, 0, &res) == 0) {
959 		gic_dist_physaddr = res.start;
960 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
961 	}
962 }
963 
964 #else
965 #define gic_init_physaddr(node)  do { } while (0)
966 #endif
967 
968 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
969 				irq_hw_number_t hw)
970 {
971 	struct gic_chip_data *gic = d->host_data;
972 
973 	if (hw < 32) {
974 		irq_set_percpu_devid(irq);
975 		irq_domain_set_info(d, irq, hw, &gic->chip, d->host_data,
976 				    handle_percpu_devid_irq, NULL, NULL);
977 	} else {
978 		irq_domain_set_info(d, irq, hw, &gic->chip, d->host_data,
979 				    handle_fasteoi_irq, NULL, NULL);
980 		irq_set_probe(irq);
981 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
982 	}
983 	return 0;
984 }
985 
986 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
987 {
988 }
989 
990 static int gic_irq_domain_translate(struct irq_domain *d,
991 				    struct irq_fwspec *fwspec,
992 				    unsigned long *hwirq,
993 				    unsigned int *type)
994 {
995 	if (is_of_node(fwspec->fwnode)) {
996 		if (fwspec->param_count < 3)
997 			return -EINVAL;
998 
999 		/* Get the interrupt number and add 16 to skip over SGIs */
1000 		*hwirq = fwspec->param[1] + 16;
1001 
1002 		/*
1003 		 * For SPIs, we need to add 16 more to get the GIC irq
1004 		 * ID number
1005 		 */
1006 		if (!fwspec->param[0])
1007 			*hwirq += 16;
1008 
1009 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
1010 
1011 		/* Make it clear that broken DTs are... broken */
1012 		WARN_ON(*type == IRQ_TYPE_NONE);
1013 		return 0;
1014 	}
1015 
1016 	if (is_fwnode_irqchip(fwspec->fwnode)) {
1017 		if(fwspec->param_count != 2)
1018 			return -EINVAL;
1019 
1020 		*hwirq = fwspec->param[0];
1021 		*type = fwspec->param[1];
1022 
1023 		WARN_ON(*type == IRQ_TYPE_NONE);
1024 		return 0;
1025 	}
1026 
1027 	return -EINVAL;
1028 }
1029 
1030 static int gic_starting_cpu(unsigned int cpu)
1031 {
1032 	gic_cpu_init(&gic_data[0]);
1033 	return 0;
1034 }
1035 
1036 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
1037 				unsigned int nr_irqs, void *arg)
1038 {
1039 	int i, ret;
1040 	irq_hw_number_t hwirq;
1041 	unsigned int type = IRQ_TYPE_NONE;
1042 	struct irq_fwspec *fwspec = arg;
1043 
1044 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
1045 	if (ret)
1046 		return ret;
1047 
1048 	for (i = 0; i < nr_irqs; i++) {
1049 		ret = gic_irq_domain_map(domain, virq + i, hwirq + i);
1050 		if (ret)
1051 			return ret;
1052 	}
1053 
1054 	return 0;
1055 }
1056 
1057 static const struct irq_domain_ops gic_irq_domain_hierarchy_ops = {
1058 	.translate = gic_irq_domain_translate,
1059 	.alloc = gic_irq_domain_alloc,
1060 	.free = irq_domain_free_irqs_top,
1061 };
1062 
1063 static const struct irq_domain_ops gic_irq_domain_ops = {
1064 	.map = gic_irq_domain_map,
1065 	.unmap = gic_irq_domain_unmap,
1066 };
1067 
1068 static void gic_init_chip(struct gic_chip_data *gic, struct device *dev,
1069 			  const char *name, bool use_eoimode1)
1070 {
1071 	/* Initialize irq_chip */
1072 	gic->chip = gic_chip;
1073 	gic->chip.name = name;
1074 	gic->chip.parent_device = dev;
1075 
1076 	if (use_eoimode1) {
1077 		gic->chip.irq_mask = gic_eoimode1_mask_irq;
1078 		gic->chip.irq_eoi = gic_eoimode1_eoi_irq;
1079 		gic->chip.irq_set_vcpu_affinity = gic_irq_set_vcpu_affinity;
1080 	}
1081 
1082 #ifdef CONFIG_SMP
1083 	if (gic == &gic_data[0])
1084 		gic->chip.irq_set_affinity = gic_set_affinity;
1085 #endif
1086 }
1087 
1088 static int gic_init_bases(struct gic_chip_data *gic,
1089 			  struct fwnode_handle *handle)
1090 {
1091 	int gic_irqs, ret;
1092 
1093 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1094 		/* Frankein-GIC without banked registers... */
1095 		unsigned int cpu;
1096 
1097 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
1098 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
1099 		if (WARN_ON(!gic->dist_base.percpu_base ||
1100 			    !gic->cpu_base.percpu_base)) {
1101 			ret = -ENOMEM;
1102 			goto error;
1103 		}
1104 
1105 		for_each_possible_cpu(cpu) {
1106 			u32 mpidr = cpu_logical_map(cpu);
1107 			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
1108 			unsigned long offset = gic->percpu_offset * core_id;
1109 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) =
1110 				gic->raw_dist_base + offset;
1111 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) =
1112 				gic->raw_cpu_base + offset;
1113 		}
1114 
1115 		gic_set_base_accessor(gic, gic_get_percpu_base);
1116 	} else {
1117 		/* Normal, sane GIC... */
1118 		WARN(gic->percpu_offset,
1119 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
1120 		     gic->percpu_offset);
1121 		gic->dist_base.common_base = gic->raw_dist_base;
1122 		gic->cpu_base.common_base = gic->raw_cpu_base;
1123 		gic_set_base_accessor(gic, gic_get_common_base);
1124 	}
1125 
1126 	/*
1127 	 * Find out how many interrupts are supported.
1128 	 * The GIC only supports up to 1020 interrupt sources.
1129 	 */
1130 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
1131 	gic_irqs = (gic_irqs + 1) * 32;
1132 	if (gic_irqs > 1020)
1133 		gic_irqs = 1020;
1134 	gic->gic_irqs = gic_irqs;
1135 
1136 	if (handle) {		/* DT/ACPI */
1137 		gic->domain = irq_domain_create_linear(handle, gic_irqs,
1138 						       &gic_irq_domain_hierarchy_ops,
1139 						       gic);
1140 	} else {		/* Legacy support */
1141 		/*
1142 		 * For primary GICs, skip over SGIs.
1143 		 * No secondary GIC support whatsoever.
1144 		 */
1145 		int irq_base;
1146 
1147 		gic_irqs -= 16; /* calculate # of irqs to allocate */
1148 
1149 		irq_base = irq_alloc_descs(16, 16, gic_irqs,
1150 					   numa_node_id());
1151 		if (irq_base < 0) {
1152 			WARN(1, "Cannot allocate irq_descs @ IRQ16, assuming pre-allocated\n");
1153 			irq_base = 16;
1154 		}
1155 
1156 		gic->domain = irq_domain_add_legacy(NULL, gic_irqs, irq_base,
1157 						    16, &gic_irq_domain_ops, gic);
1158 	}
1159 
1160 	if (WARN_ON(!gic->domain)) {
1161 		ret = -ENODEV;
1162 		goto error;
1163 	}
1164 
1165 	gic_dist_init(gic);
1166 	ret = gic_cpu_init(gic);
1167 	if (ret)
1168 		goto error;
1169 
1170 	ret = gic_pm_init(gic);
1171 	if (ret)
1172 		goto error;
1173 
1174 	return 0;
1175 
1176 error:
1177 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1178 		free_percpu(gic->dist_base.percpu_base);
1179 		free_percpu(gic->cpu_base.percpu_base);
1180 	}
1181 
1182 	return ret;
1183 }
1184 
1185 static int __init __gic_init_bases(struct gic_chip_data *gic,
1186 				   struct fwnode_handle *handle)
1187 {
1188 	char *name;
1189 	int i, ret;
1190 
1191 	if (WARN_ON(!gic || gic->domain))
1192 		return -EINVAL;
1193 
1194 	if (gic == &gic_data[0]) {
1195 		/*
1196 		 * Initialize the CPU interface map to all CPUs.
1197 		 * It will be refined as each CPU probes its ID.
1198 		 * This is only necessary for the primary GIC.
1199 		 */
1200 		for (i = 0; i < NR_GIC_CPU_IF; i++)
1201 			gic_cpu_map[i] = 0xff;
1202 #ifdef CONFIG_SMP
1203 		set_smp_cross_call(gic_raise_softirq);
1204 #endif
1205 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GIC_STARTING,
1206 					  "irqchip/arm/gic:starting",
1207 					  gic_starting_cpu, NULL);
1208 		set_handle_irq(gic_handle_irq);
1209 		if (static_branch_likely(&supports_deactivate_key))
1210 			pr_info("GIC: Using split EOI/Deactivate mode\n");
1211 	}
1212 
1213 	if (static_branch_likely(&supports_deactivate_key) && gic == &gic_data[0]) {
1214 		name = kasprintf(GFP_KERNEL, "GICv2");
1215 		gic_init_chip(gic, NULL, name, true);
1216 	} else {
1217 		name = kasprintf(GFP_KERNEL, "GIC-%d", (int)(gic-&gic_data[0]));
1218 		gic_init_chip(gic, NULL, name, false);
1219 	}
1220 
1221 	ret = gic_init_bases(gic, handle);
1222 	if (ret)
1223 		kfree(name);
1224 
1225 	return ret;
1226 }
1227 
1228 void __init gic_init(void __iomem *dist_base, void __iomem *cpu_base)
1229 {
1230 	struct gic_chip_data *gic;
1231 
1232 	/*
1233 	 * Non-DT/ACPI systems won't run a hypervisor, so let's not
1234 	 * bother with these...
1235 	 */
1236 	static_branch_disable(&supports_deactivate_key);
1237 
1238 	gic = &gic_data[0];
1239 	gic->raw_dist_base = dist_base;
1240 	gic->raw_cpu_base = cpu_base;
1241 
1242 	__gic_init_bases(gic, NULL);
1243 }
1244 
1245 static void gic_teardown(struct gic_chip_data *gic)
1246 {
1247 	if (WARN_ON(!gic))
1248 		return;
1249 
1250 	if (gic->raw_dist_base)
1251 		iounmap(gic->raw_dist_base);
1252 	if (gic->raw_cpu_base)
1253 		iounmap(gic->raw_cpu_base);
1254 }
1255 
1256 #ifdef CONFIG_OF
1257 static int gic_cnt __initdata;
1258 static bool gicv2_force_probe;
1259 
1260 static int __init gicv2_force_probe_cfg(char *buf)
1261 {
1262 	return strtobool(buf, &gicv2_force_probe);
1263 }
1264 early_param("irqchip.gicv2_force_probe", gicv2_force_probe_cfg);
1265 
1266 static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
1267 {
1268 	struct resource cpuif_res;
1269 
1270 	of_address_to_resource(node, 1, &cpuif_res);
1271 
1272 	if (!is_hyp_mode_available())
1273 		return false;
1274 	if (resource_size(&cpuif_res) < SZ_8K) {
1275 		void __iomem *alt;
1276 		/*
1277 		 * Check for a stupid firmware that only exposes the
1278 		 * first page of a GICv2.
1279 		 */
1280 		if (!gic_check_gicv2(*base))
1281 			return false;
1282 
1283 		if (!gicv2_force_probe) {
1284 			pr_warn("GIC: GICv2 detected, but range too small and irqchip.gicv2_force_probe not set\n");
1285 			return false;
1286 		}
1287 
1288 		alt = ioremap(cpuif_res.start, SZ_8K);
1289 		if (!alt)
1290 			return false;
1291 		if (!gic_check_gicv2(alt + SZ_4K)) {
1292 			/*
1293 			 * The first page was that of a GICv2, and
1294 			 * the second was *something*. Let's trust it
1295 			 * to be a GICv2, and update the mapping.
1296 			 */
1297 			pr_warn("GIC: GICv2 at %pa, but range is too small (broken DT?), assuming 8kB\n",
1298 				&cpuif_res.start);
1299 			iounmap(*base);
1300 			*base = alt;
1301 			return true;
1302 		}
1303 
1304 		/*
1305 		 * We detected *two* initial GICv2 pages in a
1306 		 * row. Could be a GICv2 aliased over two 64kB
1307 		 * pages. Update the resource, map the iospace, and
1308 		 * pray.
1309 		 */
1310 		iounmap(alt);
1311 		alt = ioremap(cpuif_res.start, SZ_128K);
1312 		if (!alt)
1313 			return false;
1314 		pr_warn("GIC: Aliased GICv2 at %pa, trying to find the canonical range over 128kB\n",
1315 			&cpuif_res.start);
1316 		cpuif_res.end = cpuif_res.start + SZ_128K -1;
1317 		iounmap(*base);
1318 		*base = alt;
1319 	}
1320 	if (resource_size(&cpuif_res) == SZ_128K) {
1321 		/*
1322 		 * Verify that we have the first 4kB of a GICv2
1323 		 * aliased over the first 64kB by checking the
1324 		 * GICC_IIDR register on both ends.
1325 		 */
1326 		if (!gic_check_gicv2(*base) ||
1327 		    !gic_check_gicv2(*base + 0xf000))
1328 			return false;
1329 
1330 		/*
1331 		 * Move the base up by 60kB, so that we have a 8kB
1332 		 * contiguous region, which allows us to use GICC_DIR
1333 		 * at its normal offset. Please pass me that bucket.
1334 		 */
1335 		*base += 0xf000;
1336 		cpuif_res.start += 0xf000;
1337 		pr_warn("GIC: Adjusting CPU interface base to %pa\n",
1338 			&cpuif_res.start);
1339 	}
1340 
1341 	return true;
1342 }
1343 
1344 static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
1345 {
1346 	if (!gic || !node)
1347 		return -EINVAL;
1348 
1349 	gic->raw_dist_base = of_iomap(node, 0);
1350 	if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
1351 		goto error;
1352 
1353 	gic->raw_cpu_base = of_iomap(node, 1);
1354 	if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n"))
1355 		goto error;
1356 
1357 	if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
1358 		gic->percpu_offset = 0;
1359 
1360 	return 0;
1361 
1362 error:
1363 	gic_teardown(gic);
1364 
1365 	return -ENOMEM;
1366 }
1367 
1368 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1369 {
1370 	int ret;
1371 
1372 	if (!dev || !dev->of_node || !gic || !irq)
1373 		return -EINVAL;
1374 
1375 	*gic = devm_kzalloc(dev, sizeof(**gic), GFP_KERNEL);
1376 	if (!*gic)
1377 		return -ENOMEM;
1378 
1379 	gic_init_chip(*gic, dev, dev->of_node->name, false);
1380 
1381 	ret = gic_of_setup(*gic, dev->of_node);
1382 	if (ret)
1383 		return ret;
1384 
1385 	ret = gic_init_bases(*gic, &dev->of_node->fwnode);
1386 	if (ret) {
1387 		gic_teardown(*gic);
1388 		return ret;
1389 	}
1390 
1391 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq, *gic);
1392 
1393 	return 0;
1394 }
1395 
1396 static void __init gic_of_setup_kvm_info(struct device_node *node)
1397 {
1398 	int ret;
1399 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1400 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1401 
1402 	gic_v2_kvm_info.type = GIC_V2;
1403 
1404 	gic_v2_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
1405 	if (!gic_v2_kvm_info.maint_irq)
1406 		return;
1407 
1408 	ret = of_address_to_resource(node, 2, vctrl_res);
1409 	if (ret)
1410 		return;
1411 
1412 	ret = of_address_to_resource(node, 3, vcpu_res);
1413 	if (ret)
1414 		return;
1415 
1416 	if (static_branch_likely(&supports_deactivate_key))
1417 		gic_set_kvm_info(&gic_v2_kvm_info);
1418 }
1419 
1420 int __init
1421 gic_of_init(struct device_node *node, struct device_node *parent)
1422 {
1423 	struct gic_chip_data *gic;
1424 	int irq, ret;
1425 
1426 	if (WARN_ON(!node))
1427 		return -ENODEV;
1428 
1429 	if (WARN_ON(gic_cnt >= CONFIG_ARM_GIC_MAX_NR))
1430 		return -EINVAL;
1431 
1432 	gic = &gic_data[gic_cnt];
1433 
1434 	ret = gic_of_setup(gic, node);
1435 	if (ret)
1436 		return ret;
1437 
1438 	/*
1439 	 * Disable split EOI/Deactivate if either HYP is not available
1440 	 * or the CPU interface is too small.
1441 	 */
1442 	if (gic_cnt == 0 && !gic_check_eoimode(node, &gic->raw_cpu_base))
1443 		static_branch_disable(&supports_deactivate_key);
1444 
1445 	ret = __gic_init_bases(gic, &node->fwnode);
1446 	if (ret) {
1447 		gic_teardown(gic);
1448 		return ret;
1449 	}
1450 
1451 	if (!gic_cnt) {
1452 		gic_init_physaddr(node);
1453 		gic_of_setup_kvm_info(node);
1454 	}
1455 
1456 	if (parent) {
1457 		irq = irq_of_parse_and_map(node, 0);
1458 		gic_cascade_irq(gic_cnt, irq);
1459 	}
1460 
1461 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1462 		gicv2m_init(&node->fwnode, gic_data[gic_cnt].domain);
1463 
1464 	gic_cnt++;
1465 	return 0;
1466 }
1467 IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1468 IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
1469 IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
1470 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1471 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1472 IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1473 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1474 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1475 IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init);
1476 #else
1477 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1478 {
1479 	return -ENOTSUPP;
1480 }
1481 #endif
1482 
1483 #ifdef CONFIG_ACPI
1484 static struct
1485 {
1486 	phys_addr_t cpu_phys_base;
1487 	u32 maint_irq;
1488 	int maint_irq_mode;
1489 	phys_addr_t vctrl_base;
1490 	phys_addr_t vcpu_base;
1491 } acpi_data __initdata;
1492 
1493 static int __init
1494 gic_acpi_parse_madt_cpu(union acpi_subtable_headers *header,
1495 			const unsigned long end)
1496 {
1497 	struct acpi_madt_generic_interrupt *processor;
1498 	phys_addr_t gic_cpu_base;
1499 	static int cpu_base_assigned;
1500 
1501 	processor = (struct acpi_madt_generic_interrupt *)header;
1502 
1503 	if (BAD_MADT_GICC_ENTRY(processor, end))
1504 		return -EINVAL;
1505 
1506 	/*
1507 	 * There is no support for non-banked GICv1/2 register in ACPI spec.
1508 	 * All CPU interface addresses have to be the same.
1509 	 */
1510 	gic_cpu_base = processor->base_address;
1511 	if (cpu_base_assigned && gic_cpu_base != acpi_data.cpu_phys_base)
1512 		return -EINVAL;
1513 
1514 	acpi_data.cpu_phys_base = gic_cpu_base;
1515 	acpi_data.maint_irq = processor->vgic_interrupt;
1516 	acpi_data.maint_irq_mode = (processor->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
1517 				    ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
1518 	acpi_data.vctrl_base = processor->gich_base_address;
1519 	acpi_data.vcpu_base = processor->gicv_base_address;
1520 
1521 	cpu_base_assigned = 1;
1522 	return 0;
1523 }
1524 
1525 /* The things you have to do to just *count* something... */
1526 static int __init acpi_dummy_func(union acpi_subtable_headers *header,
1527 				  const unsigned long end)
1528 {
1529 	return 0;
1530 }
1531 
1532 static bool __init acpi_gic_redist_is_present(void)
1533 {
1534 	return acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
1535 				     acpi_dummy_func, 0) > 0;
1536 }
1537 
1538 static bool __init gic_validate_dist(struct acpi_subtable_header *header,
1539 				     struct acpi_probe_entry *ape)
1540 {
1541 	struct acpi_madt_generic_distributor *dist;
1542 	dist = (struct acpi_madt_generic_distributor *)header;
1543 
1544 	return (dist->version == ape->driver_data &&
1545 		(dist->version != ACPI_MADT_GIC_VERSION_NONE ||
1546 		 !acpi_gic_redist_is_present()));
1547 }
1548 
1549 #define ACPI_GICV2_DIST_MEM_SIZE	(SZ_4K)
1550 #define ACPI_GIC_CPU_IF_MEM_SIZE	(SZ_8K)
1551 #define ACPI_GICV2_VCTRL_MEM_SIZE	(SZ_4K)
1552 #define ACPI_GICV2_VCPU_MEM_SIZE	(SZ_8K)
1553 
1554 static void __init gic_acpi_setup_kvm_info(void)
1555 {
1556 	int irq;
1557 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1558 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1559 
1560 	gic_v2_kvm_info.type = GIC_V2;
1561 
1562 	if (!acpi_data.vctrl_base)
1563 		return;
1564 
1565 	vctrl_res->flags = IORESOURCE_MEM;
1566 	vctrl_res->start = acpi_data.vctrl_base;
1567 	vctrl_res->end = vctrl_res->start + ACPI_GICV2_VCTRL_MEM_SIZE - 1;
1568 
1569 	if (!acpi_data.vcpu_base)
1570 		return;
1571 
1572 	vcpu_res->flags = IORESOURCE_MEM;
1573 	vcpu_res->start = acpi_data.vcpu_base;
1574 	vcpu_res->end = vcpu_res->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
1575 
1576 	irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
1577 				acpi_data.maint_irq_mode,
1578 				ACPI_ACTIVE_HIGH);
1579 	if (irq <= 0)
1580 		return;
1581 
1582 	gic_v2_kvm_info.maint_irq = irq;
1583 
1584 	gic_set_kvm_info(&gic_v2_kvm_info);
1585 }
1586 
1587 static int __init gic_v2_acpi_init(union acpi_subtable_headers *header,
1588 				   const unsigned long end)
1589 {
1590 	struct acpi_madt_generic_distributor *dist;
1591 	struct fwnode_handle *domain_handle;
1592 	struct gic_chip_data *gic = &gic_data[0];
1593 	int count, ret;
1594 
1595 	/* Collect CPU base addresses */
1596 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1597 				      gic_acpi_parse_madt_cpu, 0);
1598 	if (count <= 0) {
1599 		pr_err("No valid GICC entries exist\n");
1600 		return -EINVAL;
1601 	}
1602 
1603 	gic->raw_cpu_base = ioremap(acpi_data.cpu_phys_base, ACPI_GIC_CPU_IF_MEM_SIZE);
1604 	if (!gic->raw_cpu_base) {
1605 		pr_err("Unable to map GICC registers\n");
1606 		return -ENOMEM;
1607 	}
1608 
1609 	dist = (struct acpi_madt_generic_distributor *)header;
1610 	gic->raw_dist_base = ioremap(dist->base_address,
1611 				     ACPI_GICV2_DIST_MEM_SIZE);
1612 	if (!gic->raw_dist_base) {
1613 		pr_err("Unable to map GICD registers\n");
1614 		gic_teardown(gic);
1615 		return -ENOMEM;
1616 	}
1617 
1618 	/*
1619 	 * Disable split EOI/Deactivate if HYP is not available. ACPI
1620 	 * guarantees that we'll always have a GICv2, so the CPU
1621 	 * interface will always be the right size.
1622 	 */
1623 	if (!is_hyp_mode_available())
1624 		static_branch_disable(&supports_deactivate_key);
1625 
1626 	/*
1627 	 * Initialize GIC instance zero (no multi-GIC support).
1628 	 */
1629 	domain_handle = irq_domain_alloc_fwnode(&dist->base_address);
1630 	if (!domain_handle) {
1631 		pr_err("Unable to allocate domain handle\n");
1632 		gic_teardown(gic);
1633 		return -ENOMEM;
1634 	}
1635 
1636 	ret = __gic_init_bases(gic, domain_handle);
1637 	if (ret) {
1638 		pr_err("Failed to initialise GIC\n");
1639 		irq_domain_free_fwnode(domain_handle);
1640 		gic_teardown(gic);
1641 		return ret;
1642 	}
1643 
1644 	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
1645 
1646 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1647 		gicv2m_init(NULL, gic_data[0].domain);
1648 
1649 	if (static_branch_likely(&supports_deactivate_key))
1650 		gic_acpi_setup_kvm_info();
1651 
1652 	return 0;
1653 }
1654 IRQCHIP_ACPI_DECLARE(gic_v2, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1655 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_V2,
1656 		     gic_v2_acpi_init);
1657 IRQCHIP_ACPI_DECLARE(gic_v2_maybe, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1658 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_NONE,
1659 		     gic_v2_acpi_init);
1660 #endif
1661