xref: /linux/drivers/irqchip/irq-gic.c (revision 60684c2bd35064043360e6f716d1b7c20e967b7d)
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/kstrtox.h>
23 #include <linux/err.h>
24 #include <linux/module.h>
25 #include <linux/list.h>
26 #include <linux/smp.h>
27 #include <linux/cpu.h>
28 #include <linux/cpu_pm.h>
29 #include <linux/cpumask.h>
30 #include <linux/io.h>
31 #include <linux/of.h>
32 #include <linux/of_address.h>
33 #include <linux/of_irq.h>
34 #include <linux/acpi.h>
35 #include <linux/irqdomain.h>
36 #include <linux/interrupt.h>
37 #include <linux/percpu.h>
38 #include <linux/seq_file.h>
39 #include <linux/slab.h>
40 #include <linux/irqchip.h>
41 #include <linux/irqchip/chained_irq.h>
42 #include <linux/irqchip/arm-gic.h>
43 
44 #include <asm/cputype.h>
45 #include <asm/irq.h>
46 #include <asm/exception.h>
47 #include <asm/smp_plat.h>
48 #include <asm/virt.h>
49 
50 #include "irq-gic-common.h"
51 
52 #ifdef CONFIG_ARM64
53 #include <asm/cpufeature.h>
54 
55 static void gic_check_cpu_features(void)
56 {
57 	WARN_TAINT_ONCE(this_cpu_has_cap(ARM64_HAS_GIC_CPUIF_SYSREGS),
58 			TAINT_CPU_OUT_OF_SPEC,
59 			"GICv3 system registers enabled, broken firmware!\n");
60 }
61 #else
62 #define gic_check_cpu_features()	do { } while(0)
63 #endif
64 
65 union gic_base {
66 	void __iomem *common_base;
67 	void __percpu * __iomem *percpu_base;
68 };
69 
70 struct gic_chip_data {
71 	union gic_base dist_base;
72 	union gic_base cpu_base;
73 	void __iomem *raw_dist_base;
74 	void __iomem *raw_cpu_base;
75 	u32 percpu_offset;
76 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
77 	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
78 	u32 saved_spi_active[DIV_ROUND_UP(1020, 32)];
79 	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
80 	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
81 	u32 __percpu *saved_ppi_enable;
82 	u32 __percpu *saved_ppi_active;
83 	u32 __percpu *saved_ppi_conf;
84 #endif
85 	struct irq_domain *domain;
86 	unsigned int gic_irqs;
87 };
88 
89 #ifdef CONFIG_BL_SWITCHER
90 
91 static DEFINE_RAW_SPINLOCK(cpu_map_lock);
92 
93 #define gic_lock_irqsave(f)		\
94 	raw_spin_lock_irqsave(&cpu_map_lock, (f))
95 #define gic_unlock_irqrestore(f)	\
96 	raw_spin_unlock_irqrestore(&cpu_map_lock, (f))
97 
98 #define gic_lock()			raw_spin_lock(&cpu_map_lock)
99 #define gic_unlock()			raw_spin_unlock(&cpu_map_lock)
100 
101 #else
102 
103 #define gic_lock_irqsave(f)		do { (void)(f); } while(0)
104 #define gic_unlock_irqrestore(f)	do { (void)(f); } while(0)
105 
106 #define gic_lock()			do { } while(0)
107 #define gic_unlock()			do { } while(0)
108 
109 #endif
110 
111 static DEFINE_STATIC_KEY_FALSE(needs_rmw_access);
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 __initdata;
126 
127 static DEFINE_PER_CPU(u32, sgi_intid);
128 
129 #ifdef CONFIG_GIC_NON_BANKED
130 static DEFINE_STATIC_KEY_FALSE(frankengic_key);
131 
132 static void enable_frankengic(void)
133 {
134 	static_branch_enable(&frankengic_key);
135 }
136 
137 static inline void __iomem *__get_base(union gic_base *base)
138 {
139 	if (static_branch_unlikely(&frankengic_key))
140 		return raw_cpu_read(*base->percpu_base);
141 
142 	return base->common_base;
143 }
144 
145 #define gic_data_dist_base(d)	__get_base(&(d)->dist_base)
146 #define gic_data_cpu_base(d)	__get_base(&(d)->cpu_base)
147 #else
148 #define gic_data_dist_base(d)	((d)->dist_base.common_base)
149 #define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
150 #define enable_frankengic()	do { } while(0)
151 #endif
152 
153 static inline void __iomem *gic_dist_base(struct irq_data *d)
154 {
155 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
156 	return gic_data_dist_base(gic_data);
157 }
158 
159 static inline void __iomem *gic_cpu_base(struct irq_data *d)
160 {
161 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
162 	return gic_data_cpu_base(gic_data);
163 }
164 
165 static inline unsigned int gic_irq(struct irq_data *d)
166 {
167 	return d->hwirq;
168 }
169 
170 static inline bool cascading_gic_irq(struct irq_data *d)
171 {
172 	void *data = irq_data_get_irq_handler_data(d);
173 
174 	/*
175 	 * If handler_data is set, this is a cascading interrupt, and
176 	 * it cannot possibly be forwarded.
177 	 */
178 	return data != NULL;
179 }
180 
181 /*
182  * Routines to acknowledge, disable and enable interrupts
183  */
184 static void gic_poke_irq(struct irq_data *d, u32 offset)
185 {
186 	u32 mask = 1 << (gic_irq(d) % 32);
187 	writel_relaxed(mask, gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4);
188 }
189 
190 static int gic_peek_irq(struct irq_data *d, u32 offset)
191 {
192 	u32 mask = 1 << (gic_irq(d) % 32);
193 	return !!(readl_relaxed(gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4) & mask);
194 }
195 
196 static void gic_mask_irq(struct irq_data *d)
197 {
198 	gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
199 }
200 
201 static void gic_eoimode1_mask_irq(struct irq_data *d)
202 {
203 	gic_mask_irq(d);
204 	/*
205 	 * When masking a forwarded interrupt, make sure it is
206 	 * deactivated as well.
207 	 *
208 	 * This ensures that an interrupt that is getting
209 	 * disabled/masked will not get "stuck", because there is
210 	 * noone to deactivate it (guest is being terminated).
211 	 */
212 	if (irqd_is_forwarded_to_vcpu(d))
213 		gic_poke_irq(d, GIC_DIST_ACTIVE_CLEAR);
214 }
215 
216 static void gic_unmask_irq(struct irq_data *d)
217 {
218 	gic_poke_irq(d, GIC_DIST_ENABLE_SET);
219 }
220 
221 static void gic_eoi_irq(struct irq_data *d)
222 {
223 	u32 hwirq = gic_irq(d);
224 
225 	if (hwirq < 16)
226 		hwirq = this_cpu_read(sgi_intid);
227 
228 	writel_relaxed(hwirq, gic_cpu_base(d) + GIC_CPU_EOI);
229 }
230 
231 static void gic_eoimode1_eoi_irq(struct irq_data *d)
232 {
233 	u32 hwirq = gic_irq(d);
234 
235 	/* Do not deactivate an IRQ forwarded to a vcpu. */
236 	if (irqd_is_forwarded_to_vcpu(d))
237 		return;
238 
239 	if (hwirq < 16)
240 		hwirq = this_cpu_read(sgi_intid);
241 
242 	writel_relaxed(hwirq, gic_cpu_base(d) + GIC_CPU_DEACTIVATE);
243 }
244 
245 static int gic_irq_set_irqchip_state(struct irq_data *d,
246 				     enum irqchip_irq_state which, bool val)
247 {
248 	u32 reg;
249 
250 	switch (which) {
251 	case IRQCHIP_STATE_PENDING:
252 		reg = val ? GIC_DIST_PENDING_SET : GIC_DIST_PENDING_CLEAR;
253 		break;
254 
255 	case IRQCHIP_STATE_ACTIVE:
256 		reg = val ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR;
257 		break;
258 
259 	case IRQCHIP_STATE_MASKED:
260 		reg = val ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET;
261 		break;
262 
263 	default:
264 		return -EINVAL;
265 	}
266 
267 	gic_poke_irq(d, reg);
268 	return 0;
269 }
270 
271 static int gic_irq_get_irqchip_state(struct irq_data *d,
272 				      enum irqchip_irq_state which, bool *val)
273 {
274 	switch (which) {
275 	case IRQCHIP_STATE_PENDING:
276 		*val = gic_peek_irq(d, GIC_DIST_PENDING_SET);
277 		break;
278 
279 	case IRQCHIP_STATE_ACTIVE:
280 		*val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET);
281 		break;
282 
283 	case IRQCHIP_STATE_MASKED:
284 		*val = !gic_peek_irq(d, GIC_DIST_ENABLE_SET);
285 		break;
286 
287 	default:
288 		return -EINVAL;
289 	}
290 
291 	return 0;
292 }
293 
294 static int gic_set_type(struct irq_data *d, unsigned int type)
295 {
296 	void __iomem *base = gic_dist_base(d);
297 	unsigned int gicirq = gic_irq(d);
298 	int ret;
299 
300 	/* Interrupt configuration for SGIs can't be changed */
301 	if (gicirq < 16)
302 		return type != IRQ_TYPE_EDGE_RISING ? -EINVAL : 0;
303 
304 	/* SPIs have restrictions on the supported types */
305 	if (gicirq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
306 			    type != IRQ_TYPE_EDGE_RISING)
307 		return -EINVAL;
308 
309 	ret = gic_configure_irq(gicirq, type, base + GIC_DIST_CONFIG, NULL);
310 	if (ret && gicirq < 32) {
311 		/* Misconfigured PPIs are usually not fatal */
312 		pr_warn("GIC: PPI%d is secure or misconfigured\n", gicirq - 16);
313 		ret = 0;
314 	}
315 
316 	return ret;
317 }
318 
319 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
320 {
321 	/* Only interrupts on the primary GIC can be forwarded to a vcpu. */
322 	if (cascading_gic_irq(d) || gic_irq(d) < 16)
323 		return -EINVAL;
324 
325 	if (vcpu)
326 		irqd_set_forwarded_to_vcpu(d);
327 	else
328 		irqd_clr_forwarded_to_vcpu(d);
329 	return 0;
330 }
331 
332 static int gic_retrigger(struct irq_data *data)
333 {
334 	return !gic_irq_set_irqchip_state(data, IRQCHIP_STATE_PENDING, true);
335 }
336 
337 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
338 {
339 	u32 irqstat, irqnr;
340 	struct gic_chip_data *gic = &gic_data[0];
341 	void __iomem *cpu_base = gic_data_cpu_base(gic);
342 
343 	do {
344 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
345 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
346 
347 		if (unlikely(irqnr >= 1020))
348 			break;
349 
350 		if (static_branch_likely(&supports_deactivate_key))
351 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
352 		isb();
353 
354 		/*
355 		 * Ensure any shared data written by the CPU sending the IPI
356 		 * is read after we've read the ACK register on the GIC.
357 		 *
358 		 * Pairs with the write barrier in gic_ipi_send_mask
359 		 */
360 		if (irqnr <= 15) {
361 			smp_rmb();
362 
363 			/*
364 			 * The GIC encodes the source CPU in GICC_IAR,
365 			 * leading to the deactivation to fail if not
366 			 * written back as is to GICC_EOI.  Stash the INTID
367 			 * away for gic_eoi_irq() to write back.  This only
368 			 * works because we don't nest SGIs...
369 			 */
370 			this_cpu_write(sgi_intid, irqstat);
371 		}
372 
373 		generic_handle_domain_irq(gic->domain, irqnr);
374 	} while (1);
375 }
376 
377 static void gic_handle_cascade_irq(struct irq_desc *desc)
378 {
379 	struct gic_chip_data *chip_data = irq_desc_get_handler_data(desc);
380 	struct irq_chip *chip = irq_desc_get_chip(desc);
381 	unsigned int gic_irq;
382 	unsigned long status;
383 	int ret;
384 
385 	chained_irq_enter(chip, desc);
386 
387 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
388 
389 	gic_irq = (status & GICC_IAR_INT_ID_MASK);
390 	if (gic_irq == GICC_INT_SPURIOUS)
391 		goto out;
392 
393 	isb();
394 	ret = generic_handle_domain_irq(chip_data->domain, gic_irq);
395 	if (unlikely(ret))
396 		handle_bad_irq(desc);
397  out:
398 	chained_irq_exit(chip, desc);
399 }
400 
401 static void gic_irq_print_chip(struct irq_data *d, struct seq_file *p)
402 {
403 	struct gic_chip_data *gic = irq_data_get_irq_chip_data(d);
404 
405 	if (gic->domain->pm_dev)
406 		seq_printf(p, gic->domain->pm_dev->of_node->name);
407 	else
408 		seq_printf(p, "GIC-%d", (int)(gic - &gic_data[0]));
409 }
410 
411 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
412 {
413 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
414 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq,
415 					 &gic_data[gic_nr]);
416 }
417 
418 static u8 gic_get_cpumask(struct gic_chip_data *gic)
419 {
420 	void __iomem *base = gic_data_dist_base(gic);
421 	u32 mask, i;
422 
423 	for (i = mask = 0; i < 32; i += 4) {
424 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
425 		mask |= mask >> 16;
426 		mask |= mask >> 8;
427 		if (mask)
428 			break;
429 	}
430 
431 	if (!mask && num_possible_cpus() > 1)
432 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
433 
434 	return mask;
435 }
436 
437 static bool gic_check_gicv2(void __iomem *base)
438 {
439 	u32 val = readl_relaxed(base + GIC_CPU_IDENT);
440 	return (val & 0xff0fff) == 0x02043B;
441 }
442 
443 static void gic_cpu_if_up(struct gic_chip_data *gic)
444 {
445 	void __iomem *cpu_base = gic_data_cpu_base(gic);
446 	u32 bypass = 0;
447 	u32 mode = 0;
448 	int i;
449 
450 	if (gic == &gic_data[0] && static_branch_likely(&supports_deactivate_key))
451 		mode = GIC_CPU_CTRL_EOImodeNS;
452 
453 	if (gic_check_gicv2(cpu_base))
454 		for (i = 0; i < 4; i++)
455 			writel_relaxed(0, cpu_base + GIC_CPU_ACTIVEPRIO + i * 4);
456 
457 	/*
458 	* Preserve bypass disable bits to be written back later
459 	*/
460 	bypass = readl(cpu_base + GIC_CPU_CTRL);
461 	bypass &= GICC_DIS_BYPASS_MASK;
462 
463 	writel_relaxed(bypass | mode | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
464 }
465 
466 
467 static void gic_dist_init(struct gic_chip_data *gic)
468 {
469 	unsigned int i;
470 	u32 cpumask;
471 	unsigned int gic_irqs = gic->gic_irqs;
472 	void __iomem *base = gic_data_dist_base(gic);
473 
474 	writel_relaxed(GICD_DISABLE, base + GIC_DIST_CTRL);
475 
476 	/*
477 	 * Set all global interrupts to this CPU only.
478 	 */
479 	cpumask = gic_get_cpumask(gic);
480 	cpumask |= cpumask << 8;
481 	cpumask |= cpumask << 16;
482 	for (i = 32; i < gic_irqs; i += 4)
483 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
484 
485 	gic_dist_config(base, gic_irqs, NULL);
486 
487 	writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL);
488 }
489 
490 static int gic_cpu_init(struct gic_chip_data *gic)
491 {
492 	void __iomem *dist_base = gic_data_dist_base(gic);
493 	void __iomem *base = gic_data_cpu_base(gic);
494 	unsigned int cpu_mask, cpu = smp_processor_id();
495 	int i;
496 
497 	/*
498 	 * Setting up the CPU map is only relevant for the primary GIC
499 	 * because any nested/secondary GICs do not directly interface
500 	 * with the CPU(s).
501 	 */
502 	if (gic == &gic_data[0]) {
503 		/*
504 		 * Get what the GIC says our CPU mask is.
505 		 */
506 		if (WARN_ON(cpu >= NR_GIC_CPU_IF))
507 			return -EINVAL;
508 
509 		gic_check_cpu_features();
510 		cpu_mask = gic_get_cpumask(gic);
511 		gic_cpu_map[cpu] = cpu_mask;
512 
513 		/*
514 		 * Clear our mask from the other map entries in case they're
515 		 * still undefined.
516 		 */
517 		for (i = 0; i < NR_GIC_CPU_IF; i++)
518 			if (i != cpu)
519 				gic_cpu_map[i] &= ~cpu_mask;
520 	}
521 
522 	gic_cpu_config(dist_base, 32, NULL);
523 
524 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
525 	gic_cpu_if_up(gic);
526 
527 	return 0;
528 }
529 
530 int gic_cpu_if_down(unsigned int gic_nr)
531 {
532 	void __iomem *cpu_base;
533 	u32 val = 0;
534 
535 	if (gic_nr >= CONFIG_ARM_GIC_MAX_NR)
536 		return -EINVAL;
537 
538 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
539 	val = readl(cpu_base + GIC_CPU_CTRL);
540 	val &= ~GICC_ENABLE;
541 	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
542 
543 	return 0;
544 }
545 
546 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
547 /*
548  * Saves the GIC distributor registers during suspend or idle.  Must be called
549  * with interrupts disabled but before powering down the GIC.  After calling
550  * this function, no interrupts will be delivered by the GIC, and another
551  * platform-specific wakeup source must be enabled.
552  */
553 void gic_dist_save(struct gic_chip_data *gic)
554 {
555 	unsigned int gic_irqs;
556 	void __iomem *dist_base;
557 	int i;
558 
559 	if (WARN_ON(!gic))
560 		return;
561 
562 	gic_irqs = gic->gic_irqs;
563 	dist_base = gic_data_dist_base(gic);
564 
565 	if (!dist_base)
566 		return;
567 
568 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
569 		gic->saved_spi_conf[i] =
570 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
571 
572 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
573 		gic->saved_spi_target[i] =
574 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
575 
576 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
577 		gic->saved_spi_enable[i] =
578 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
579 
580 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
581 		gic->saved_spi_active[i] =
582 			readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
583 }
584 
585 /*
586  * Restores the GIC distributor registers during resume or when coming out of
587  * idle.  Must be called before enabling interrupts.  If a level interrupt
588  * that occurred while the GIC was suspended is still present, it will be
589  * handled normally, but any edge interrupts that occurred will not be seen by
590  * the GIC and need to be handled by the platform-specific wakeup source.
591  */
592 void gic_dist_restore(struct gic_chip_data *gic)
593 {
594 	unsigned int gic_irqs;
595 	unsigned int i;
596 	void __iomem *dist_base;
597 
598 	if (WARN_ON(!gic))
599 		return;
600 
601 	gic_irqs = gic->gic_irqs;
602 	dist_base = gic_data_dist_base(gic);
603 
604 	if (!dist_base)
605 		return;
606 
607 	writel_relaxed(GICD_DISABLE, dist_base + GIC_DIST_CTRL);
608 
609 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
610 		writel_relaxed(gic->saved_spi_conf[i],
611 			dist_base + GIC_DIST_CONFIG + i * 4);
612 
613 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
614 		writel_relaxed(GICD_INT_DEF_PRI_X4,
615 			dist_base + GIC_DIST_PRI + i * 4);
616 
617 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
618 		writel_relaxed(gic->saved_spi_target[i],
619 			dist_base + GIC_DIST_TARGET + i * 4);
620 
621 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
622 		writel_relaxed(GICD_INT_EN_CLR_X32,
623 			dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
624 		writel_relaxed(gic->saved_spi_enable[i],
625 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
626 	}
627 
628 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
629 		writel_relaxed(GICD_INT_EN_CLR_X32,
630 			dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
631 		writel_relaxed(gic->saved_spi_active[i],
632 			dist_base + GIC_DIST_ACTIVE_SET + i * 4);
633 	}
634 
635 	writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL);
636 }
637 
638 void gic_cpu_save(struct gic_chip_data *gic)
639 {
640 	int i;
641 	u32 *ptr;
642 	void __iomem *dist_base;
643 	void __iomem *cpu_base;
644 
645 	if (WARN_ON(!gic))
646 		return;
647 
648 	dist_base = gic_data_dist_base(gic);
649 	cpu_base = gic_data_cpu_base(gic);
650 
651 	if (!dist_base || !cpu_base)
652 		return;
653 
654 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
655 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
656 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
657 
658 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
659 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
660 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
661 
662 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
663 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
664 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
665 
666 }
667 
668 void gic_cpu_restore(struct gic_chip_data *gic)
669 {
670 	int i;
671 	u32 *ptr;
672 	void __iomem *dist_base;
673 	void __iomem *cpu_base;
674 
675 	if (WARN_ON(!gic))
676 		return;
677 
678 	dist_base = gic_data_dist_base(gic);
679 	cpu_base = gic_data_cpu_base(gic);
680 
681 	if (!dist_base || !cpu_base)
682 		return;
683 
684 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
685 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
686 		writel_relaxed(GICD_INT_EN_CLR_X32,
687 			       dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
688 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
689 	}
690 
691 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
692 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
693 		writel_relaxed(GICD_INT_EN_CLR_X32,
694 			       dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
695 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ACTIVE_SET + i * 4);
696 	}
697 
698 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
699 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
700 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
701 
702 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
703 		writel_relaxed(GICD_INT_DEF_PRI_X4,
704 					dist_base + GIC_DIST_PRI + i * 4);
705 
706 	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
707 	gic_cpu_if_up(gic);
708 }
709 
710 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
711 {
712 	int i;
713 
714 	for (i = 0; i < CONFIG_ARM_GIC_MAX_NR; i++) {
715 		switch (cmd) {
716 		case CPU_PM_ENTER:
717 			gic_cpu_save(&gic_data[i]);
718 			break;
719 		case CPU_PM_ENTER_FAILED:
720 		case CPU_PM_EXIT:
721 			gic_cpu_restore(&gic_data[i]);
722 			break;
723 		case CPU_CLUSTER_PM_ENTER:
724 			gic_dist_save(&gic_data[i]);
725 			break;
726 		case CPU_CLUSTER_PM_ENTER_FAILED:
727 		case CPU_CLUSTER_PM_EXIT:
728 			gic_dist_restore(&gic_data[i]);
729 			break;
730 		}
731 	}
732 
733 	return NOTIFY_OK;
734 }
735 
736 static struct notifier_block gic_notifier_block = {
737 	.notifier_call = gic_notifier,
738 };
739 
740 static int gic_pm_init(struct gic_chip_data *gic)
741 {
742 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
743 		sizeof(u32));
744 	if (WARN_ON(!gic->saved_ppi_enable))
745 		return -ENOMEM;
746 
747 	gic->saved_ppi_active = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
748 		sizeof(u32));
749 	if (WARN_ON(!gic->saved_ppi_active))
750 		goto free_ppi_enable;
751 
752 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
753 		sizeof(u32));
754 	if (WARN_ON(!gic->saved_ppi_conf))
755 		goto free_ppi_active;
756 
757 	if (gic == &gic_data[0])
758 		cpu_pm_register_notifier(&gic_notifier_block);
759 
760 	return 0;
761 
762 free_ppi_active:
763 	free_percpu(gic->saved_ppi_active);
764 free_ppi_enable:
765 	free_percpu(gic->saved_ppi_enable);
766 
767 	return -ENOMEM;
768 }
769 #else
770 static int gic_pm_init(struct gic_chip_data *gic)
771 {
772 	return 0;
773 }
774 #endif
775 
776 #ifdef CONFIG_SMP
777 static void rmw_writeb(u8 bval, void __iomem *addr)
778 {
779 	static DEFINE_RAW_SPINLOCK(rmw_lock);
780 	unsigned long offset = (unsigned long)addr & 3UL;
781 	unsigned long shift = offset * 8;
782 	unsigned long flags;
783 	u32 val;
784 
785 	raw_spin_lock_irqsave(&rmw_lock, flags);
786 
787 	addr -= offset;
788 	val = readl_relaxed(addr);
789 	val &= ~GENMASK(shift + 7, shift);
790 	val |= bval << shift;
791 	writel_relaxed(val, addr);
792 
793 	raw_spin_unlock_irqrestore(&rmw_lock, flags);
794 }
795 
796 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
797 			    bool force)
798 {
799 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + gic_irq(d);
800 	struct gic_chip_data *gic = irq_data_get_irq_chip_data(d);
801 	unsigned int cpu;
802 
803 	if (unlikely(gic != &gic_data[0]))
804 		return -EINVAL;
805 
806 	if (!force)
807 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
808 	else
809 		cpu = cpumask_first(mask_val);
810 
811 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
812 		return -EINVAL;
813 
814 	if (static_branch_unlikely(&needs_rmw_access))
815 		rmw_writeb(gic_cpu_map[cpu], reg);
816 	else
817 		writeb_relaxed(gic_cpu_map[cpu], reg);
818 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
819 
820 	return IRQ_SET_MASK_OK_DONE;
821 }
822 
823 static void gic_ipi_send_mask(struct irq_data *d, const struct cpumask *mask)
824 {
825 	int cpu;
826 	unsigned long flags, map = 0;
827 
828 	if (unlikely(nr_cpu_ids == 1)) {
829 		/* Only one CPU? let's do a self-IPI... */
830 		writel_relaxed(2 << 24 | d->hwirq,
831 			       gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
832 		return;
833 	}
834 
835 	gic_lock_irqsave(flags);
836 
837 	/* Convert our logical CPU mask into a physical one. */
838 	for_each_cpu(cpu, mask)
839 		map |= gic_cpu_map[cpu];
840 
841 	/*
842 	 * Ensure that stores to Normal memory are visible to the
843 	 * other CPUs before they observe us issuing the IPI.
844 	 */
845 	dmb(ishst);
846 
847 	/* this always happens on GIC0 */
848 	writel_relaxed(map << 16 | d->hwirq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
849 
850 	gic_unlock_irqrestore(flags);
851 }
852 
853 static int gic_starting_cpu(unsigned int cpu)
854 {
855 	gic_cpu_init(&gic_data[0]);
856 	return 0;
857 }
858 
859 static __init void gic_smp_init(void)
860 {
861 	struct irq_fwspec sgi_fwspec = {
862 		.fwnode		= gic_data[0].domain->fwnode,
863 		.param_count	= 1,
864 	};
865 	int base_sgi;
866 
867 	cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GIC_STARTING,
868 				  "irqchip/arm/gic:starting",
869 				  gic_starting_cpu, NULL);
870 
871 	base_sgi = irq_domain_alloc_irqs(gic_data[0].domain, 8, NUMA_NO_NODE, &sgi_fwspec);
872 	if (WARN_ON(base_sgi <= 0))
873 		return;
874 
875 	set_smp_ipi_range(base_sgi, 8);
876 }
877 #else
878 #define gic_smp_init()		do { } while(0)
879 #define gic_set_affinity	NULL
880 #define gic_ipi_send_mask	NULL
881 #endif
882 
883 static const struct irq_chip gic_chip = {
884 	.irq_mask		= gic_mask_irq,
885 	.irq_unmask		= gic_unmask_irq,
886 	.irq_eoi		= gic_eoi_irq,
887 	.irq_set_type		= gic_set_type,
888 	.irq_retrigger          = gic_retrigger,
889 	.irq_set_affinity	= gic_set_affinity,
890 	.ipi_send_mask		= gic_ipi_send_mask,
891 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
892 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
893 	.irq_print_chip		= gic_irq_print_chip,
894 	.flags			= IRQCHIP_SET_TYPE_MASKED |
895 				  IRQCHIP_SKIP_SET_WAKE |
896 				  IRQCHIP_MASK_ON_SUSPEND,
897 };
898 
899 static const struct irq_chip gic_chip_mode1 = {
900 	.name			= "GICv2",
901 	.irq_mask		= gic_eoimode1_mask_irq,
902 	.irq_unmask		= gic_unmask_irq,
903 	.irq_eoi		= gic_eoimode1_eoi_irq,
904 	.irq_set_type		= gic_set_type,
905 	.irq_retrigger          = gic_retrigger,
906 	.irq_set_affinity	= gic_set_affinity,
907 	.ipi_send_mask		= gic_ipi_send_mask,
908 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
909 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
910 	.irq_set_vcpu_affinity	= gic_irq_set_vcpu_affinity,
911 	.flags			= IRQCHIP_SET_TYPE_MASKED |
912 				  IRQCHIP_SKIP_SET_WAKE |
913 				  IRQCHIP_MASK_ON_SUSPEND,
914 };
915 
916 #ifdef CONFIG_BL_SWITCHER
917 /*
918  * gic_send_sgi - send a SGI directly to given CPU interface number
919  *
920  * cpu_id: the ID for the destination CPU interface
921  * irq: the IPI number to send a SGI for
922  */
923 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
924 {
925 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
926 	cpu_id = 1 << cpu_id;
927 	/* this always happens on GIC0 */
928 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
929 }
930 
931 /*
932  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
933  *
934  * @cpu: the logical CPU number to get the GIC ID for.
935  *
936  * Return the CPU interface ID for the given logical CPU number,
937  * or -1 if the CPU number is too large or the interface ID is
938  * unknown (more than one bit set).
939  */
940 int gic_get_cpu_id(unsigned int cpu)
941 {
942 	unsigned int cpu_bit;
943 
944 	if (cpu >= NR_GIC_CPU_IF)
945 		return -1;
946 	cpu_bit = gic_cpu_map[cpu];
947 	if (cpu_bit & (cpu_bit - 1))
948 		return -1;
949 	return __ffs(cpu_bit);
950 }
951 
952 /*
953  * gic_migrate_target - migrate IRQs to another CPU interface
954  *
955  * @new_cpu_id: the CPU target ID to migrate IRQs to
956  *
957  * Migrate all peripheral interrupts with a target matching the current CPU
958  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
959  * is also updated.  Targets to other CPU interfaces are unchanged.
960  * This must be called with IRQs locally disabled.
961  */
962 void gic_migrate_target(unsigned int new_cpu_id)
963 {
964 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
965 	void __iomem *dist_base;
966 	int i, ror_val, cpu = smp_processor_id();
967 	u32 val, cur_target_mask, active_mask;
968 
969 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
970 
971 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
972 	if (!dist_base)
973 		return;
974 	gic_irqs = gic_data[gic_nr].gic_irqs;
975 
976 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
977 	cur_target_mask = 0x01010101 << cur_cpu_id;
978 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
979 
980 	gic_lock();
981 
982 	/* Update the target interface for this logical CPU */
983 	gic_cpu_map[cpu] = 1 << new_cpu_id;
984 
985 	/*
986 	 * Find all the peripheral interrupts targeting the current
987 	 * CPU interface and migrate them to the new CPU interface.
988 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
989 	 */
990 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
991 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
992 		active_mask = val & cur_target_mask;
993 		if (active_mask) {
994 			val &= ~active_mask;
995 			val |= ror32(active_mask, ror_val);
996 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
997 		}
998 	}
999 
1000 	gic_unlock();
1001 
1002 	/*
1003 	 * Now let's migrate and clear any potential SGIs that might be
1004 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
1005 	 * is a banked register, we can only forward the SGI using
1006 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
1007 	 * doesn't use that information anyway.
1008 	 *
1009 	 * For the same reason we do not adjust SGI source information
1010 	 * for previously sent SGIs by us to other CPUs either.
1011 	 */
1012 	for (i = 0; i < 16; i += 4) {
1013 		int j;
1014 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
1015 		if (!val)
1016 			continue;
1017 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
1018 		for (j = i; j < i + 4; j++) {
1019 			if (val & 0xff)
1020 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
1021 						dist_base + GIC_DIST_SOFTINT);
1022 			val >>= 8;
1023 		}
1024 	}
1025 }
1026 
1027 /*
1028  * gic_get_sgir_physaddr - get the physical address for the SGI register
1029  *
1030  * Return the physical address of the SGI register to be used
1031  * by some early assembly code when the kernel is not yet available.
1032  */
1033 static unsigned long gic_dist_physaddr;
1034 
1035 unsigned long gic_get_sgir_physaddr(void)
1036 {
1037 	if (!gic_dist_physaddr)
1038 		return 0;
1039 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
1040 }
1041 
1042 static void __init gic_init_physaddr(struct device_node *node)
1043 {
1044 	struct resource res;
1045 	if (of_address_to_resource(node, 0, &res) == 0) {
1046 		gic_dist_physaddr = res.start;
1047 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
1048 	}
1049 }
1050 
1051 #else
1052 #define gic_init_physaddr(node)  do { } while (0)
1053 #endif
1054 
1055 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
1056 				irq_hw_number_t hw)
1057 {
1058 	struct gic_chip_data *gic = d->host_data;
1059 	struct irq_data *irqd = irq_desc_get_irq_data(irq_to_desc(irq));
1060 	const struct irq_chip *chip;
1061 
1062 	chip = (static_branch_likely(&supports_deactivate_key) &&
1063 		gic == &gic_data[0]) ? &gic_chip_mode1 : &gic_chip;
1064 
1065 	switch (hw) {
1066 	case 0 ... 31:
1067 		irq_set_percpu_devid(irq);
1068 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
1069 				    handle_percpu_devid_irq, NULL, NULL);
1070 		break;
1071 	default:
1072 		irq_domain_set_info(d, irq, hw, chip, d->host_data,
1073 				    handle_fasteoi_irq, NULL, NULL);
1074 		irq_set_probe(irq);
1075 		irqd_set_single_target(irqd);
1076 		break;
1077 	}
1078 
1079 	/* Prevents SW retriggers which mess up the ACK/EOI ordering */
1080 	irqd_set_handle_enforce_irqctx(irqd);
1081 	return 0;
1082 }
1083 
1084 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
1085 {
1086 }
1087 
1088 static int gic_irq_domain_translate(struct irq_domain *d,
1089 				    struct irq_fwspec *fwspec,
1090 				    unsigned long *hwirq,
1091 				    unsigned int *type)
1092 {
1093 	if (fwspec->param_count == 1 && fwspec->param[0] < 16) {
1094 		*hwirq = fwspec->param[0];
1095 		*type = IRQ_TYPE_EDGE_RISING;
1096 		return 0;
1097 	}
1098 
1099 	if (is_of_node(fwspec->fwnode)) {
1100 		if (fwspec->param_count < 3)
1101 			return -EINVAL;
1102 
1103 		switch (fwspec->param[0]) {
1104 		case 0:			/* SPI */
1105 			*hwirq = fwspec->param[1] + 32;
1106 			break;
1107 		case 1:			/* PPI */
1108 			*hwirq = fwspec->param[1] + 16;
1109 			break;
1110 		default:
1111 			return -EINVAL;
1112 		}
1113 
1114 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
1115 
1116 		/* Make it clear that broken DTs are... broken */
1117 		WARN(*type == IRQ_TYPE_NONE,
1118 		     "HW irq %ld has invalid type\n", *hwirq);
1119 		return 0;
1120 	}
1121 
1122 	if (is_fwnode_irqchip(fwspec->fwnode)) {
1123 		if(fwspec->param_count != 2)
1124 			return -EINVAL;
1125 
1126 		if (fwspec->param[0] < 16) {
1127 			pr_err(FW_BUG "Illegal GSI%d translation request\n",
1128 			       fwspec->param[0]);
1129 			return -EINVAL;
1130 		}
1131 
1132 		*hwirq = fwspec->param[0];
1133 		*type = fwspec->param[1];
1134 
1135 		WARN(*type == IRQ_TYPE_NONE,
1136 		     "HW irq %ld has invalid type\n", *hwirq);
1137 		return 0;
1138 	}
1139 
1140 	return -EINVAL;
1141 }
1142 
1143 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
1144 				unsigned int nr_irqs, void *arg)
1145 {
1146 	int i, ret;
1147 	irq_hw_number_t hwirq;
1148 	unsigned int type = IRQ_TYPE_NONE;
1149 	struct irq_fwspec *fwspec = arg;
1150 
1151 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
1152 	if (ret)
1153 		return ret;
1154 
1155 	for (i = 0; i < nr_irqs; i++) {
1156 		ret = gic_irq_domain_map(domain, virq + i, hwirq + i);
1157 		if (ret)
1158 			return ret;
1159 	}
1160 
1161 	return 0;
1162 }
1163 
1164 static const struct irq_domain_ops gic_irq_domain_hierarchy_ops = {
1165 	.translate = gic_irq_domain_translate,
1166 	.alloc = gic_irq_domain_alloc,
1167 	.free = irq_domain_free_irqs_top,
1168 };
1169 
1170 static const struct irq_domain_ops gic_irq_domain_ops = {
1171 	.map = gic_irq_domain_map,
1172 	.unmap = gic_irq_domain_unmap,
1173 };
1174 
1175 static int gic_init_bases(struct gic_chip_data *gic,
1176 			  struct fwnode_handle *handle)
1177 {
1178 	int gic_irqs, ret;
1179 
1180 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1181 		/* Frankein-GIC without banked registers... */
1182 		unsigned int cpu;
1183 
1184 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
1185 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
1186 		if (WARN_ON(!gic->dist_base.percpu_base ||
1187 			    !gic->cpu_base.percpu_base)) {
1188 			ret = -ENOMEM;
1189 			goto error;
1190 		}
1191 
1192 		for_each_possible_cpu(cpu) {
1193 			u32 mpidr = cpu_logical_map(cpu);
1194 			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
1195 			unsigned long offset = gic->percpu_offset * core_id;
1196 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) =
1197 				gic->raw_dist_base + offset;
1198 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) =
1199 				gic->raw_cpu_base + offset;
1200 		}
1201 
1202 		enable_frankengic();
1203 	} else {
1204 		/* Normal, sane GIC... */
1205 		WARN(gic->percpu_offset,
1206 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
1207 		     gic->percpu_offset);
1208 		gic->dist_base.common_base = gic->raw_dist_base;
1209 		gic->cpu_base.common_base = gic->raw_cpu_base;
1210 	}
1211 
1212 	/*
1213 	 * Find out how many interrupts are supported.
1214 	 * The GIC only supports up to 1020 interrupt sources.
1215 	 */
1216 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
1217 	gic_irqs = (gic_irqs + 1) * 32;
1218 	if (gic_irqs > 1020)
1219 		gic_irqs = 1020;
1220 	gic->gic_irqs = gic_irqs;
1221 
1222 	if (handle) {		/* DT/ACPI */
1223 		gic->domain = irq_domain_create_linear(handle, gic_irqs,
1224 						       &gic_irq_domain_hierarchy_ops,
1225 						       gic);
1226 	} else {		/* Legacy support */
1227 		/*
1228 		 * For primary GICs, skip over SGIs.
1229 		 * No secondary GIC support whatsoever.
1230 		 */
1231 		int irq_base;
1232 
1233 		gic_irqs -= 16; /* calculate # of irqs to allocate */
1234 
1235 		irq_base = irq_alloc_descs(16, 16, gic_irqs,
1236 					   numa_node_id());
1237 		if (irq_base < 0) {
1238 			WARN(1, "Cannot allocate irq_descs @ IRQ16, assuming pre-allocated\n");
1239 			irq_base = 16;
1240 		}
1241 
1242 		gic->domain = irq_domain_add_legacy(NULL, gic_irqs, irq_base,
1243 						    16, &gic_irq_domain_ops, gic);
1244 	}
1245 
1246 	if (WARN_ON(!gic->domain)) {
1247 		ret = -ENODEV;
1248 		goto error;
1249 	}
1250 
1251 	gic_dist_init(gic);
1252 	ret = gic_cpu_init(gic);
1253 	if (ret)
1254 		goto error;
1255 
1256 	ret = gic_pm_init(gic);
1257 	if (ret)
1258 		goto error;
1259 
1260 	return 0;
1261 
1262 error:
1263 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1264 		free_percpu(gic->dist_base.percpu_base);
1265 		free_percpu(gic->cpu_base.percpu_base);
1266 	}
1267 
1268 	return ret;
1269 }
1270 
1271 static int __init __gic_init_bases(struct gic_chip_data *gic,
1272 				   struct fwnode_handle *handle)
1273 {
1274 	int i, ret;
1275 
1276 	if (WARN_ON(!gic || gic->domain))
1277 		return -EINVAL;
1278 
1279 	if (gic == &gic_data[0]) {
1280 		/*
1281 		 * Initialize the CPU interface map to all CPUs.
1282 		 * It will be refined as each CPU probes its ID.
1283 		 * This is only necessary for the primary GIC.
1284 		 */
1285 		for (i = 0; i < NR_GIC_CPU_IF; i++)
1286 			gic_cpu_map[i] = 0xff;
1287 
1288 		set_handle_irq(gic_handle_irq);
1289 		if (static_branch_likely(&supports_deactivate_key))
1290 			pr_info("GIC: Using split EOI/Deactivate mode\n");
1291 	}
1292 
1293 	ret = gic_init_bases(gic, handle);
1294 	if (gic == &gic_data[0])
1295 		gic_smp_init();
1296 
1297 	return ret;
1298 }
1299 
1300 void __init gic_init(void __iomem *dist_base, void __iomem *cpu_base)
1301 {
1302 	struct gic_chip_data *gic;
1303 
1304 	/*
1305 	 * Non-DT/ACPI systems won't run a hypervisor, so let's not
1306 	 * bother with these...
1307 	 */
1308 	static_branch_disable(&supports_deactivate_key);
1309 
1310 	gic = &gic_data[0];
1311 	gic->raw_dist_base = dist_base;
1312 	gic->raw_cpu_base = cpu_base;
1313 
1314 	__gic_init_bases(gic, NULL);
1315 }
1316 
1317 static void gic_teardown(struct gic_chip_data *gic)
1318 {
1319 	if (WARN_ON(!gic))
1320 		return;
1321 
1322 	if (gic->raw_dist_base)
1323 		iounmap(gic->raw_dist_base);
1324 	if (gic->raw_cpu_base)
1325 		iounmap(gic->raw_cpu_base);
1326 }
1327 
1328 #ifdef CONFIG_OF
1329 static int gic_cnt __initdata;
1330 static bool gicv2_force_probe;
1331 
1332 static int __init gicv2_force_probe_cfg(char *buf)
1333 {
1334 	return kstrtobool(buf, &gicv2_force_probe);
1335 }
1336 early_param("irqchip.gicv2_force_probe", gicv2_force_probe_cfg);
1337 
1338 static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
1339 {
1340 	struct resource cpuif_res;
1341 
1342 	of_address_to_resource(node, 1, &cpuif_res);
1343 
1344 	if (!is_hyp_mode_available())
1345 		return false;
1346 	if (resource_size(&cpuif_res) < SZ_8K) {
1347 		void __iomem *alt;
1348 		/*
1349 		 * Check for a stupid firmware that only exposes the
1350 		 * first page of a GICv2.
1351 		 */
1352 		if (!gic_check_gicv2(*base))
1353 			return false;
1354 
1355 		if (!gicv2_force_probe) {
1356 			pr_warn("GIC: GICv2 detected, but range too small and irqchip.gicv2_force_probe not set\n");
1357 			return false;
1358 		}
1359 
1360 		alt = ioremap(cpuif_res.start, SZ_8K);
1361 		if (!alt)
1362 			return false;
1363 		if (!gic_check_gicv2(alt + SZ_4K)) {
1364 			/*
1365 			 * The first page was that of a GICv2, and
1366 			 * the second was *something*. Let's trust it
1367 			 * to be a GICv2, and update the mapping.
1368 			 */
1369 			pr_warn("GIC: GICv2 at %pa, but range is too small (broken DT?), assuming 8kB\n",
1370 				&cpuif_res.start);
1371 			iounmap(*base);
1372 			*base = alt;
1373 			return true;
1374 		}
1375 
1376 		/*
1377 		 * We detected *two* initial GICv2 pages in a
1378 		 * row. Could be a GICv2 aliased over two 64kB
1379 		 * pages. Update the resource, map the iospace, and
1380 		 * pray.
1381 		 */
1382 		iounmap(alt);
1383 		alt = ioremap(cpuif_res.start, SZ_128K);
1384 		if (!alt)
1385 			return false;
1386 		pr_warn("GIC: Aliased GICv2 at %pa, trying to find the canonical range over 128kB\n",
1387 			&cpuif_res.start);
1388 		cpuif_res.end = cpuif_res.start + SZ_128K -1;
1389 		iounmap(*base);
1390 		*base = alt;
1391 	}
1392 	if (resource_size(&cpuif_res) == SZ_128K) {
1393 		/*
1394 		 * Verify that we have the first 4kB of a GICv2
1395 		 * aliased over the first 64kB by checking the
1396 		 * GICC_IIDR register on both ends.
1397 		 */
1398 		if (!gic_check_gicv2(*base) ||
1399 		    !gic_check_gicv2(*base + 0xf000))
1400 			return false;
1401 
1402 		/*
1403 		 * Move the base up by 60kB, so that we have a 8kB
1404 		 * contiguous region, which allows us to use GICC_DIR
1405 		 * at its normal offset. Please pass me that bucket.
1406 		 */
1407 		*base += 0xf000;
1408 		cpuif_res.start += 0xf000;
1409 		pr_warn("GIC: Adjusting CPU interface base to %pa\n",
1410 			&cpuif_res.start);
1411 	}
1412 
1413 	return true;
1414 }
1415 
1416 static bool gic_enable_rmw_access(void *data)
1417 {
1418 	/*
1419 	 * The EMEV2 class of machines has a broken interconnect, and
1420 	 * locks up on accesses that are less than 32bit. So far, only
1421 	 * the affinity setting requires it.
1422 	 */
1423 	if (of_machine_is_compatible("renesas,emev2")) {
1424 		static_branch_enable(&needs_rmw_access);
1425 		return true;
1426 	}
1427 
1428 	return false;
1429 }
1430 
1431 static const struct gic_quirk gic_quirks[] = {
1432 	{
1433 		.desc		= "broken byte access",
1434 		.compatible	= "arm,pl390",
1435 		.init		= gic_enable_rmw_access,
1436 	},
1437 	{ },
1438 };
1439 
1440 static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
1441 {
1442 	if (!gic || !node)
1443 		return -EINVAL;
1444 
1445 	gic->raw_dist_base = of_iomap(node, 0);
1446 	if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
1447 		goto error;
1448 
1449 	gic->raw_cpu_base = of_iomap(node, 1);
1450 	if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n"))
1451 		goto error;
1452 
1453 	if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
1454 		gic->percpu_offset = 0;
1455 
1456 	gic_enable_of_quirks(node, gic_quirks, gic);
1457 
1458 	return 0;
1459 
1460 error:
1461 	gic_teardown(gic);
1462 
1463 	return -ENOMEM;
1464 }
1465 
1466 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1467 {
1468 	int ret;
1469 
1470 	if (!dev || !dev->of_node || !gic || !irq)
1471 		return -EINVAL;
1472 
1473 	*gic = devm_kzalloc(dev, sizeof(**gic), GFP_KERNEL);
1474 	if (!*gic)
1475 		return -ENOMEM;
1476 
1477 	ret = gic_of_setup(*gic, dev->of_node);
1478 	if (ret)
1479 		return ret;
1480 
1481 	ret = gic_init_bases(*gic, &dev->of_node->fwnode);
1482 	if (ret) {
1483 		gic_teardown(*gic);
1484 		return ret;
1485 	}
1486 
1487 	irq_domain_set_pm_device((*gic)->domain, dev);
1488 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq, *gic);
1489 
1490 	return 0;
1491 }
1492 
1493 static void __init gic_of_setup_kvm_info(struct device_node *node)
1494 {
1495 	int ret;
1496 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1497 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1498 
1499 	gic_v2_kvm_info.type = GIC_V2;
1500 
1501 	gic_v2_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
1502 	if (!gic_v2_kvm_info.maint_irq)
1503 		return;
1504 
1505 	ret = of_address_to_resource(node, 2, vctrl_res);
1506 	if (ret)
1507 		return;
1508 
1509 	ret = of_address_to_resource(node, 3, vcpu_res);
1510 	if (ret)
1511 		return;
1512 
1513 	if (static_branch_likely(&supports_deactivate_key))
1514 		vgic_set_kvm_info(&gic_v2_kvm_info);
1515 }
1516 
1517 int __init
1518 gic_of_init(struct device_node *node, struct device_node *parent)
1519 {
1520 	struct gic_chip_data *gic;
1521 	int irq, ret;
1522 
1523 	if (WARN_ON(!node))
1524 		return -ENODEV;
1525 
1526 	if (WARN_ON(gic_cnt >= CONFIG_ARM_GIC_MAX_NR))
1527 		return -EINVAL;
1528 
1529 	gic = &gic_data[gic_cnt];
1530 
1531 	ret = gic_of_setup(gic, node);
1532 	if (ret)
1533 		return ret;
1534 
1535 	/*
1536 	 * Disable split EOI/Deactivate if either HYP is not available
1537 	 * or the CPU interface is too small.
1538 	 */
1539 	if (gic_cnt == 0 && !gic_check_eoimode(node, &gic->raw_cpu_base))
1540 		static_branch_disable(&supports_deactivate_key);
1541 
1542 	ret = __gic_init_bases(gic, &node->fwnode);
1543 	if (ret) {
1544 		gic_teardown(gic);
1545 		return ret;
1546 	}
1547 
1548 	if (!gic_cnt) {
1549 		gic_init_physaddr(node);
1550 		gic_of_setup_kvm_info(node);
1551 	}
1552 
1553 	if (parent) {
1554 		irq = irq_of_parse_and_map(node, 0);
1555 		gic_cascade_irq(gic_cnt, irq);
1556 	}
1557 
1558 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1559 		gicv2m_init(&node->fwnode, gic_data[gic_cnt].domain);
1560 
1561 	gic_cnt++;
1562 	return 0;
1563 }
1564 IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1565 IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
1566 IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
1567 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1568 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1569 IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1570 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1571 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1572 IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init);
1573 #else
1574 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1575 {
1576 	return -ENOTSUPP;
1577 }
1578 #endif
1579 
1580 #ifdef CONFIG_ACPI
1581 static struct
1582 {
1583 	phys_addr_t cpu_phys_base;
1584 	u32 maint_irq;
1585 	int maint_irq_mode;
1586 	phys_addr_t vctrl_base;
1587 	phys_addr_t vcpu_base;
1588 } acpi_data __initdata;
1589 
1590 static int __init
1591 gic_acpi_parse_madt_cpu(union acpi_subtable_headers *header,
1592 			const unsigned long end)
1593 {
1594 	struct acpi_madt_generic_interrupt *processor;
1595 	phys_addr_t gic_cpu_base;
1596 	static int cpu_base_assigned;
1597 
1598 	processor = (struct acpi_madt_generic_interrupt *)header;
1599 
1600 	if (BAD_MADT_GICC_ENTRY(processor, end))
1601 		return -EINVAL;
1602 
1603 	/*
1604 	 * There is no support for non-banked GICv1/2 register in ACPI spec.
1605 	 * All CPU interface addresses have to be the same.
1606 	 */
1607 	gic_cpu_base = processor->base_address;
1608 	if (cpu_base_assigned && gic_cpu_base != acpi_data.cpu_phys_base)
1609 		return -EINVAL;
1610 
1611 	acpi_data.cpu_phys_base = gic_cpu_base;
1612 	acpi_data.maint_irq = processor->vgic_interrupt;
1613 	acpi_data.maint_irq_mode = (processor->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
1614 				    ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
1615 	acpi_data.vctrl_base = processor->gich_base_address;
1616 	acpi_data.vcpu_base = processor->gicv_base_address;
1617 
1618 	cpu_base_assigned = 1;
1619 	return 0;
1620 }
1621 
1622 /* The things you have to do to just *count* something... */
1623 static int __init acpi_dummy_func(union acpi_subtable_headers *header,
1624 				  const unsigned long end)
1625 {
1626 	return 0;
1627 }
1628 
1629 static bool __init acpi_gic_redist_is_present(void)
1630 {
1631 	return acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
1632 				     acpi_dummy_func, 0) > 0;
1633 }
1634 
1635 static bool __init gic_validate_dist(struct acpi_subtable_header *header,
1636 				     struct acpi_probe_entry *ape)
1637 {
1638 	struct acpi_madt_generic_distributor *dist;
1639 	dist = (struct acpi_madt_generic_distributor *)header;
1640 
1641 	return (dist->version == ape->driver_data &&
1642 		(dist->version != ACPI_MADT_GIC_VERSION_NONE ||
1643 		 !acpi_gic_redist_is_present()));
1644 }
1645 
1646 #define ACPI_GICV2_DIST_MEM_SIZE	(SZ_4K)
1647 #define ACPI_GIC_CPU_IF_MEM_SIZE	(SZ_8K)
1648 #define ACPI_GICV2_VCTRL_MEM_SIZE	(SZ_4K)
1649 #define ACPI_GICV2_VCPU_MEM_SIZE	(SZ_8K)
1650 
1651 static void __init gic_acpi_setup_kvm_info(void)
1652 {
1653 	int irq;
1654 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1655 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1656 
1657 	gic_v2_kvm_info.type = GIC_V2;
1658 
1659 	if (!acpi_data.vctrl_base)
1660 		return;
1661 
1662 	vctrl_res->flags = IORESOURCE_MEM;
1663 	vctrl_res->start = acpi_data.vctrl_base;
1664 	vctrl_res->end = vctrl_res->start + ACPI_GICV2_VCTRL_MEM_SIZE - 1;
1665 
1666 	if (!acpi_data.vcpu_base)
1667 		return;
1668 
1669 	vcpu_res->flags = IORESOURCE_MEM;
1670 	vcpu_res->start = acpi_data.vcpu_base;
1671 	vcpu_res->end = vcpu_res->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
1672 
1673 	irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
1674 				acpi_data.maint_irq_mode,
1675 				ACPI_ACTIVE_HIGH);
1676 	if (irq <= 0)
1677 		return;
1678 
1679 	gic_v2_kvm_info.maint_irq = irq;
1680 
1681 	vgic_set_kvm_info(&gic_v2_kvm_info);
1682 }
1683 
1684 static struct fwnode_handle *gsi_domain_handle;
1685 
1686 static struct fwnode_handle *gic_v2_get_gsi_domain_id(u32 gsi)
1687 {
1688 	return gsi_domain_handle;
1689 }
1690 
1691 static int __init gic_v2_acpi_init(union acpi_subtable_headers *header,
1692 				   const unsigned long end)
1693 {
1694 	struct acpi_madt_generic_distributor *dist;
1695 	struct gic_chip_data *gic = &gic_data[0];
1696 	int count, ret;
1697 
1698 	/* Collect CPU base addresses */
1699 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1700 				      gic_acpi_parse_madt_cpu, 0);
1701 	if (count <= 0) {
1702 		pr_err("No valid GICC entries exist\n");
1703 		return -EINVAL;
1704 	}
1705 
1706 	gic->raw_cpu_base = ioremap(acpi_data.cpu_phys_base, ACPI_GIC_CPU_IF_MEM_SIZE);
1707 	if (!gic->raw_cpu_base) {
1708 		pr_err("Unable to map GICC registers\n");
1709 		return -ENOMEM;
1710 	}
1711 
1712 	dist = (struct acpi_madt_generic_distributor *)header;
1713 	gic->raw_dist_base = ioremap(dist->base_address,
1714 				     ACPI_GICV2_DIST_MEM_SIZE);
1715 	if (!gic->raw_dist_base) {
1716 		pr_err("Unable to map GICD registers\n");
1717 		gic_teardown(gic);
1718 		return -ENOMEM;
1719 	}
1720 
1721 	/*
1722 	 * Disable split EOI/Deactivate if HYP is not available. ACPI
1723 	 * guarantees that we'll always have a GICv2, so the CPU
1724 	 * interface will always be the right size.
1725 	 */
1726 	if (!is_hyp_mode_available())
1727 		static_branch_disable(&supports_deactivate_key);
1728 
1729 	/*
1730 	 * Initialize GIC instance zero (no multi-GIC support).
1731 	 */
1732 	gsi_domain_handle = irq_domain_alloc_fwnode(&dist->base_address);
1733 	if (!gsi_domain_handle) {
1734 		pr_err("Unable to allocate domain handle\n");
1735 		gic_teardown(gic);
1736 		return -ENOMEM;
1737 	}
1738 
1739 	ret = __gic_init_bases(gic, gsi_domain_handle);
1740 	if (ret) {
1741 		pr_err("Failed to initialise GIC\n");
1742 		irq_domain_free_fwnode(gsi_domain_handle);
1743 		gic_teardown(gic);
1744 		return ret;
1745 	}
1746 
1747 	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, gic_v2_get_gsi_domain_id);
1748 
1749 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1750 		gicv2m_init(NULL, gic_data[0].domain);
1751 
1752 	if (static_branch_likely(&supports_deactivate_key))
1753 		gic_acpi_setup_kvm_info();
1754 
1755 	return 0;
1756 }
1757 IRQCHIP_ACPI_DECLARE(gic_v2, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1758 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_V2,
1759 		     gic_v2_acpi_init);
1760 IRQCHIP_ACPI_DECLARE(gic_v2_maybe, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1761 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_NONE,
1762 		     gic_v2_acpi_init);
1763 #endif
1764