1 /*
2  *  Copyright (C) 2002 ARM Limited, All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * Interrupt architecture for the GIC:
9  *
10  * o There is one Interrupt Distributor, which receives interrupts
11  *   from system devices and sends them to the Interrupt Controllers.
12  *
13  * o There is one CPU Interface per CPU, which sends interrupts sent
14  *   by the Distributor, and interrupts generated locally, to the
15  *   associated CPU. The base address of the CPU interface is usually
16  *   aliased so that the same address points to different chips depending
17  *   on the CPU it is accessed from.
18  *
19  * Note that IRQs 0-31 are special - they are local to each CPU.
20  * As such, the enable set/clear, pending set/clear and active bit
21  * registers are banked per-cpu for these sources.
22  */
23 #include <linux/init.h>
24 #include <linux/kernel.h>
25 #include <linux/err.h>
26 #include <linux/module.h>
27 #include <linux/list.h>
28 #include <linux/smp.h>
29 #include <linux/cpu.h>
30 #include <linux/cpu_pm.h>
31 #include <linux/cpumask.h>
32 #include <linux/io.h>
33 #include <linux/of.h>
34 #include <linux/of_address.h>
35 #include <linux/of_irq.h>
36 #include <linux/acpi.h>
37 #include <linux/irqdomain.h>
38 #include <linux/interrupt.h>
39 #include <linux/percpu.h>
40 #include <linux/slab.h>
41 #include <linux/irqchip.h>
42 #include <linux/irqchip/chained_irq.h>
43 #include <linux/irqchip/arm-gic.h>
44 
45 #include <asm/cputype.h>
46 #include <asm/irq.h>
47 #include <asm/exception.h>
48 #include <asm/smp_plat.h>
49 #include <asm/virt.h>
50 
51 #include "irq-gic-common.h"
52 
53 #ifdef CONFIG_ARM64
54 #include <asm/cpufeature.h>
55 
gic_check_cpu_features(void)56 static void gic_check_cpu_features(void)
57 {
58 	WARN_TAINT_ONCE(this_cpu_has_cap(ARM64_HAS_SYSREG_GIC_CPUIF),
59 			TAINT_CPU_OUT_OF_SPEC,
60 			"GICv3 system registers enabled, broken firmware!\n");
61 }
62 #else
63 #define gic_check_cpu_features()	do { } while(0)
64 #endif
65 
66 union gic_base {
67 	void __iomem *common_base;
68 	void __percpu * __iomem *percpu_base;
69 };
70 
71 struct gic_chip_data {
72 	struct irq_chip chip;
73 	union gic_base dist_base;
74 	union gic_base cpu_base;
75 	void __iomem *raw_dist_base;
76 	void __iomem *raw_cpu_base;
77 	u32 percpu_offset;
78 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
79 	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
80 	u32 saved_spi_active[DIV_ROUND_UP(1020, 32)];
81 	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
82 	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
83 	u32 __percpu *saved_ppi_enable;
84 	u32 __percpu *saved_ppi_active;
85 	u32 __percpu *saved_ppi_conf;
86 #endif
87 	struct irq_domain *domain;
88 	unsigned int gic_irqs;
89 #ifdef CONFIG_GIC_NON_BANKED
90 	void __iomem *(*get_base)(union gic_base *);
91 #endif
92 };
93 
94 #ifdef CONFIG_BL_SWITCHER
95 
96 static DEFINE_RAW_SPINLOCK(cpu_map_lock);
97 
98 #define gic_lock_irqsave(f)		\
99 	raw_spin_lock_irqsave(&cpu_map_lock, (f))
100 #define gic_unlock_irqrestore(f)	\
101 	raw_spin_unlock_irqrestore(&cpu_map_lock, (f))
102 
103 #define gic_lock()			raw_spin_lock(&cpu_map_lock)
104 #define gic_unlock()			raw_spin_unlock(&cpu_map_lock)
105 
106 #else
107 
108 #define gic_lock_irqsave(f)		do { (void)(f); } while(0)
109 #define gic_unlock_irqrestore(f)	do { (void)(f); } while(0)
110 
111 #define gic_lock()			do { } while(0)
112 #define gic_unlock()			do { } while(0)
113 
114 #endif
115 
116 /*
117  * The GIC mapping of CPU interfaces does not necessarily match
118  * the logical CPU numbering.  Let's use a mapping as returned
119  * by the GIC itself.
120  */
121 #define NR_GIC_CPU_IF 8
122 static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
123 
124 static DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
125 
126 static struct gic_chip_data gic_data[CONFIG_ARM_GIC_MAX_NR] __read_mostly;
127 
128 static struct gic_kvm_info gic_v2_kvm_info;
129 
130 #ifdef CONFIG_GIC_NON_BANKED
gic_get_percpu_base(union gic_base * base)131 static void __iomem *gic_get_percpu_base(union gic_base *base)
132 {
133 	return raw_cpu_read(*base->percpu_base);
134 }
135 
gic_get_common_base(union gic_base * base)136 static void __iomem *gic_get_common_base(union gic_base *base)
137 {
138 	return base->common_base;
139 }
140 
gic_data_dist_base(struct gic_chip_data * data)141 static inline void __iomem *gic_data_dist_base(struct gic_chip_data *data)
142 {
143 	return data->get_base(&data->dist_base);
144 }
145 
gic_data_cpu_base(struct gic_chip_data * data)146 static inline void __iomem *gic_data_cpu_base(struct gic_chip_data *data)
147 {
148 	return data->get_base(&data->cpu_base);
149 }
150 
gic_set_base_accessor(struct gic_chip_data * data,void __iomem * (* f)(union gic_base *))151 static inline void gic_set_base_accessor(struct gic_chip_data *data,
152 					 void __iomem *(*f)(union gic_base *))
153 {
154 	data->get_base = f;
155 }
156 #else
157 #define gic_data_dist_base(d)	((d)->dist_base.common_base)
158 #define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
159 #define gic_set_base_accessor(d, f)
160 #endif
161 
gic_dist_base(struct irq_data * d)162 static inline void __iomem *gic_dist_base(struct irq_data *d)
163 {
164 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
165 	return gic_data_dist_base(gic_data);
166 }
167 
gic_cpu_base(struct irq_data * d)168 static inline void __iomem *gic_cpu_base(struct irq_data *d)
169 {
170 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
171 	return gic_data_cpu_base(gic_data);
172 }
173 
gic_irq(struct irq_data * d)174 static inline unsigned int gic_irq(struct irq_data *d)
175 {
176 	return d->hwirq;
177 }
178 
cascading_gic_irq(struct irq_data * d)179 static inline bool cascading_gic_irq(struct irq_data *d)
180 {
181 	void *data = irq_data_get_irq_handler_data(d);
182 
183 	/*
184 	 * If handler_data is set, this is a cascading interrupt, and
185 	 * it cannot possibly be forwarded.
186 	 */
187 	return data != NULL;
188 }
189 
190 /*
191  * Routines to acknowledge, disable and enable interrupts
192  */
gic_poke_irq(struct irq_data * d,u32 offset)193 static void gic_poke_irq(struct irq_data *d, u32 offset)
194 {
195 	u32 mask = 1 << (gic_irq(d) % 32);
196 	writel_relaxed(mask, gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4);
197 }
198 
gic_peek_irq(struct irq_data * d,u32 offset)199 static int gic_peek_irq(struct irq_data *d, u32 offset)
200 {
201 	u32 mask = 1 << (gic_irq(d) % 32);
202 	return !!(readl_relaxed(gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4) & mask);
203 }
204 
gic_mask_irq(struct irq_data * d)205 static void gic_mask_irq(struct irq_data *d)
206 {
207 	gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
208 }
209 
gic_eoimode1_mask_irq(struct irq_data * d)210 static void gic_eoimode1_mask_irq(struct irq_data *d)
211 {
212 	gic_mask_irq(d);
213 	/*
214 	 * When masking a forwarded interrupt, make sure it is
215 	 * deactivated as well.
216 	 *
217 	 * This ensures that an interrupt that is getting
218 	 * disabled/masked will not get "stuck", because there is
219 	 * noone to deactivate it (guest is being terminated).
220 	 */
221 	if (irqd_is_forwarded_to_vcpu(d))
222 		gic_poke_irq(d, GIC_DIST_ACTIVE_CLEAR);
223 }
224 
gic_unmask_irq(struct irq_data * d)225 static void gic_unmask_irq(struct irq_data *d)
226 {
227 	gic_poke_irq(d, GIC_DIST_ENABLE_SET);
228 }
229 
gic_eoi_irq(struct irq_data * d)230 static void gic_eoi_irq(struct irq_data *d)
231 {
232 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
233 }
234 
gic_eoimode1_eoi_irq(struct irq_data * d)235 static void gic_eoimode1_eoi_irq(struct irq_data *d)
236 {
237 	/* Do not deactivate an IRQ forwarded to a vcpu. */
238 	if (irqd_is_forwarded_to_vcpu(d))
239 		return;
240 
241 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_DEACTIVATE);
242 }
243 
gic_irq_set_irqchip_state(struct irq_data * d,enum irqchip_irq_state which,bool val)244 static int gic_irq_set_irqchip_state(struct irq_data *d,
245 				     enum irqchip_irq_state which, bool val)
246 {
247 	u32 reg;
248 
249 	switch (which) {
250 	case IRQCHIP_STATE_PENDING:
251 		reg = val ? GIC_DIST_PENDING_SET : GIC_DIST_PENDING_CLEAR;
252 		break;
253 
254 	case IRQCHIP_STATE_ACTIVE:
255 		reg = val ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR;
256 		break;
257 
258 	case IRQCHIP_STATE_MASKED:
259 		reg = val ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET;
260 		break;
261 
262 	default:
263 		return -EINVAL;
264 	}
265 
266 	gic_poke_irq(d, reg);
267 	return 0;
268 }
269 
gic_irq_get_irqchip_state(struct irq_data * d,enum irqchip_irq_state which,bool * val)270 static int gic_irq_get_irqchip_state(struct irq_data *d,
271 				      enum irqchip_irq_state which, bool *val)
272 {
273 	switch (which) {
274 	case IRQCHIP_STATE_PENDING:
275 		*val = gic_peek_irq(d, GIC_DIST_PENDING_SET);
276 		break;
277 
278 	case IRQCHIP_STATE_ACTIVE:
279 		*val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET);
280 		break;
281 
282 	case IRQCHIP_STATE_MASKED:
283 		*val = !gic_peek_irq(d, GIC_DIST_ENABLE_SET);
284 		break;
285 
286 	default:
287 		return -EINVAL;
288 	}
289 
290 	return 0;
291 }
292 
gic_set_type(struct irq_data * d,unsigned int type)293 static int gic_set_type(struct irq_data *d, unsigned int type)
294 {
295 	void __iomem *base = gic_dist_base(d);
296 	unsigned int gicirq = gic_irq(d);
297 
298 	/* Interrupt configuration for SGIs can't be changed */
299 	if (gicirq < 16)
300 		return -EINVAL;
301 
302 	/* SPIs have restrictions on the supported types */
303 	if (gicirq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
304 			    type != IRQ_TYPE_EDGE_RISING)
305 		return -EINVAL;
306 
307 	return gic_configure_irq(gicirq, type, base, NULL);
308 }
309 
gic_irq_set_vcpu_affinity(struct irq_data * d,void * vcpu)310 static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
311 {
312 	/* Only interrupts on the primary GIC can be forwarded to a vcpu. */
313 	if (cascading_gic_irq(d))
314 		return -EINVAL;
315 
316 	if (vcpu)
317 		irqd_set_forwarded_to_vcpu(d);
318 	else
319 		irqd_clr_forwarded_to_vcpu(d);
320 	return 0;
321 }
322 
323 #ifdef CONFIG_SMP
gic_set_affinity(struct irq_data * d,const struct cpumask * mask_val,bool force)324 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
325 			    bool force)
326 {
327 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + gic_irq(d);
328 	unsigned int cpu;
329 
330 	if (!force)
331 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
332 	else
333 		cpu = cpumask_first(mask_val);
334 
335 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
336 		return -EINVAL;
337 
338 	writeb_relaxed(gic_cpu_map[cpu], reg);
339 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
340 
341 	return IRQ_SET_MASK_OK_DONE;
342 }
343 #endif
344 
gic_handle_irq(struct pt_regs * regs)345 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
346 {
347 	u32 irqstat, irqnr;
348 	struct gic_chip_data *gic = &gic_data[0];
349 	void __iomem *cpu_base = gic_data_cpu_base(gic);
350 
351 	do {
352 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
353 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
354 
355 		if (likely(irqnr > 15 && irqnr < 1020)) {
356 			if (static_branch_likely(&supports_deactivate_key))
357 				writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
358 			isb();
359 			handle_domain_irq(gic->domain, irqnr, regs);
360 			continue;
361 		}
362 		if (irqnr < 16) {
363 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
364 			if (static_branch_likely(&supports_deactivate_key))
365 				writel_relaxed(irqstat, cpu_base + GIC_CPU_DEACTIVATE);
366 #ifdef CONFIG_SMP
367 			/*
368 			 * Ensure any shared data written by the CPU sending
369 			 * the IPI is read after we've read the ACK register
370 			 * on the GIC.
371 			 *
372 			 * Pairs with the write barrier in gic_raise_softirq
373 			 */
374 			smp_rmb();
375 			handle_IPI(irqnr, regs);
376 #endif
377 			continue;
378 		}
379 		break;
380 	} while (1);
381 }
382 
gic_handle_cascade_irq(struct irq_desc * desc)383 static void gic_handle_cascade_irq(struct irq_desc *desc)
384 {
385 	struct gic_chip_data *chip_data = irq_desc_get_handler_data(desc);
386 	struct irq_chip *chip = irq_desc_get_chip(desc);
387 	unsigned int cascade_irq, gic_irq;
388 	unsigned long status;
389 
390 	chained_irq_enter(chip, desc);
391 
392 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
393 
394 	gic_irq = (status & GICC_IAR_INT_ID_MASK);
395 	if (gic_irq == GICC_INT_SPURIOUS)
396 		goto out;
397 
398 	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
399 	if (unlikely(gic_irq < 32 || gic_irq > 1020)) {
400 		handle_bad_irq(desc);
401 	} else {
402 		isb();
403 		generic_handle_irq(cascade_irq);
404 	}
405 
406  out:
407 	chained_irq_exit(chip, desc);
408 }
409 
410 static const struct irq_chip gic_chip = {
411 	.irq_mask		= gic_mask_irq,
412 	.irq_unmask		= gic_unmask_irq,
413 	.irq_eoi		= gic_eoi_irq,
414 	.irq_set_type		= gic_set_type,
415 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
416 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
417 	.flags			= IRQCHIP_SET_TYPE_MASKED |
418 				  IRQCHIP_SKIP_SET_WAKE |
419 				  IRQCHIP_MASK_ON_SUSPEND,
420 };
421 
gic_cascade_irq(unsigned int gic_nr,unsigned int irq)422 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
423 {
424 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
425 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq,
426 					 &gic_data[gic_nr]);
427 }
428 
gic_get_cpumask(struct gic_chip_data * gic)429 static u8 gic_get_cpumask(struct gic_chip_data *gic)
430 {
431 	void __iomem *base = gic_data_dist_base(gic);
432 	u32 mask, i;
433 
434 	for (i = mask = 0; i < 32; i += 4) {
435 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
436 		mask |= mask >> 16;
437 		mask |= mask >> 8;
438 		if (mask)
439 			break;
440 	}
441 
442 	if (!mask && num_possible_cpus() > 1)
443 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
444 
445 	return mask;
446 }
447 
gic_check_gicv2(void __iomem * base)448 static bool gic_check_gicv2(void __iomem *base)
449 {
450 	u32 val = readl_relaxed(base + GIC_CPU_IDENT);
451 	return (val & 0xff0fff) == 0x02043B;
452 }
453 
gic_cpu_if_up(struct gic_chip_data * gic)454 static void gic_cpu_if_up(struct gic_chip_data *gic)
455 {
456 	void __iomem *cpu_base = gic_data_cpu_base(gic);
457 	u32 bypass = 0;
458 	u32 mode = 0;
459 	int i;
460 
461 	if (gic == &gic_data[0] && static_branch_likely(&supports_deactivate_key))
462 		mode = GIC_CPU_CTRL_EOImodeNS;
463 
464 	if (gic_check_gicv2(cpu_base))
465 		for (i = 0; i < 4; i++)
466 			writel_relaxed(0, cpu_base + GIC_CPU_ACTIVEPRIO + i * 4);
467 
468 	/*
469 	* Preserve bypass disable bits to be written back later
470 	*/
471 	bypass = readl(cpu_base + GIC_CPU_CTRL);
472 	bypass &= GICC_DIS_BYPASS_MASK;
473 
474 	writel_relaxed(bypass | mode | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
475 }
476 
477 
gic_dist_init(struct gic_chip_data * gic)478 static void gic_dist_init(struct gic_chip_data *gic)
479 {
480 	unsigned int i;
481 	u32 cpumask;
482 	unsigned int gic_irqs = gic->gic_irqs;
483 	void __iomem *base = gic_data_dist_base(gic);
484 
485 	writel_relaxed(GICD_DISABLE, base + GIC_DIST_CTRL);
486 
487 	/*
488 	 * Set all global interrupts to this CPU only.
489 	 */
490 	cpumask = gic_get_cpumask(gic);
491 	cpumask |= cpumask << 8;
492 	cpumask |= cpumask << 16;
493 	for (i = 32; i < gic_irqs; i += 4)
494 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
495 
496 	gic_dist_config(base, gic_irqs, NULL);
497 
498 	writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL);
499 }
500 
gic_cpu_init(struct gic_chip_data * gic)501 static int gic_cpu_init(struct gic_chip_data *gic)
502 {
503 	void __iomem *dist_base = gic_data_dist_base(gic);
504 	void __iomem *base = gic_data_cpu_base(gic);
505 	unsigned int cpu_mask, cpu = smp_processor_id();
506 	int i;
507 
508 	/*
509 	 * Setting up the CPU map is only relevant for the primary GIC
510 	 * because any nested/secondary GICs do not directly interface
511 	 * with the CPU(s).
512 	 */
513 	if (gic == &gic_data[0]) {
514 		/*
515 		 * Get what the GIC says our CPU mask is.
516 		 */
517 		if (WARN_ON(cpu >= NR_GIC_CPU_IF))
518 			return -EINVAL;
519 
520 		gic_check_cpu_features();
521 		cpu_mask = gic_get_cpumask(gic);
522 		gic_cpu_map[cpu] = cpu_mask;
523 
524 		/*
525 		 * Clear our mask from the other map entries in case they're
526 		 * still undefined.
527 		 */
528 		for (i = 0; i < NR_GIC_CPU_IF; i++)
529 			if (i != cpu)
530 				gic_cpu_map[i] &= ~cpu_mask;
531 	}
532 
533 	gic_cpu_config(dist_base, NULL);
534 
535 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
536 	gic_cpu_if_up(gic);
537 
538 	return 0;
539 }
540 
gic_cpu_if_down(unsigned int gic_nr)541 int gic_cpu_if_down(unsigned int gic_nr)
542 {
543 	void __iomem *cpu_base;
544 	u32 val = 0;
545 
546 	if (gic_nr >= CONFIG_ARM_GIC_MAX_NR)
547 		return -EINVAL;
548 
549 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
550 	val = readl(cpu_base + GIC_CPU_CTRL);
551 	val &= ~GICC_ENABLE;
552 	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
553 
554 	return 0;
555 }
556 
557 #if defined(CONFIG_CPU_PM) || defined(CONFIG_ARM_GIC_PM)
558 /*
559  * Saves the GIC distributor registers during suspend or idle.  Must be called
560  * with interrupts disabled but before powering down the GIC.  After calling
561  * this function, no interrupts will be delivered by the GIC, and another
562  * platform-specific wakeup source must be enabled.
563  */
gic_dist_save(struct gic_chip_data * gic)564 void gic_dist_save(struct gic_chip_data *gic)
565 {
566 	unsigned int gic_irqs;
567 	void __iomem *dist_base;
568 	int i;
569 
570 	if (WARN_ON(!gic))
571 		return;
572 
573 	gic_irqs = gic->gic_irqs;
574 	dist_base = gic_data_dist_base(gic);
575 
576 	if (!dist_base)
577 		return;
578 
579 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
580 		gic->saved_spi_conf[i] =
581 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
582 
583 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
584 		gic->saved_spi_target[i] =
585 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
586 
587 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
588 		gic->saved_spi_enable[i] =
589 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
590 
591 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
592 		gic->saved_spi_active[i] =
593 			readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
594 }
595 
596 /*
597  * Restores the GIC distributor registers during resume or when coming out of
598  * idle.  Must be called before enabling interrupts.  If a level interrupt
599  * that occured while the GIC was suspended is still present, it will be
600  * handled normally, but any edge interrupts that occured will not be seen by
601  * the GIC and need to be handled by the platform-specific wakeup source.
602  */
gic_dist_restore(struct gic_chip_data * gic)603 void gic_dist_restore(struct gic_chip_data *gic)
604 {
605 	unsigned int gic_irqs;
606 	unsigned int i;
607 	void __iomem *dist_base;
608 
609 	if (WARN_ON(!gic))
610 		return;
611 
612 	gic_irqs = gic->gic_irqs;
613 	dist_base = gic_data_dist_base(gic);
614 
615 	if (!dist_base)
616 		return;
617 
618 	writel_relaxed(GICD_DISABLE, dist_base + GIC_DIST_CTRL);
619 
620 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
621 		writel_relaxed(gic->saved_spi_conf[i],
622 			dist_base + GIC_DIST_CONFIG + i * 4);
623 
624 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
625 		writel_relaxed(GICD_INT_DEF_PRI_X4,
626 			dist_base + GIC_DIST_PRI + i * 4);
627 
628 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
629 		writel_relaxed(gic->saved_spi_target[i],
630 			dist_base + GIC_DIST_TARGET + i * 4);
631 
632 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
633 		writel_relaxed(GICD_INT_EN_CLR_X32,
634 			dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
635 		writel_relaxed(gic->saved_spi_enable[i],
636 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
637 	}
638 
639 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++) {
640 		writel_relaxed(GICD_INT_EN_CLR_X32,
641 			dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
642 		writel_relaxed(gic->saved_spi_active[i],
643 			dist_base + GIC_DIST_ACTIVE_SET + i * 4);
644 	}
645 
646 	writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL);
647 }
648 
gic_cpu_save(struct gic_chip_data * gic)649 void gic_cpu_save(struct gic_chip_data *gic)
650 {
651 	int i;
652 	u32 *ptr;
653 	void __iomem *dist_base;
654 	void __iomem *cpu_base;
655 
656 	if (WARN_ON(!gic))
657 		return;
658 
659 	dist_base = gic_data_dist_base(gic);
660 	cpu_base = gic_data_cpu_base(gic);
661 
662 	if (!dist_base || !cpu_base)
663 		return;
664 
665 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
666 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
667 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
668 
669 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
670 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
671 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ACTIVE_SET + i * 4);
672 
673 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
674 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
675 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
676 
677 }
678 
gic_cpu_restore(struct gic_chip_data * gic)679 void gic_cpu_restore(struct gic_chip_data *gic)
680 {
681 	int i;
682 	u32 *ptr;
683 	void __iomem *dist_base;
684 	void __iomem *cpu_base;
685 
686 	if (WARN_ON(!gic))
687 		return;
688 
689 	dist_base = gic_data_dist_base(gic);
690 	cpu_base = gic_data_cpu_base(gic);
691 
692 	if (!dist_base || !cpu_base)
693 		return;
694 
695 	ptr = raw_cpu_ptr(gic->saved_ppi_enable);
696 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
697 		writel_relaxed(GICD_INT_EN_CLR_X32,
698 			       dist_base + GIC_DIST_ENABLE_CLEAR + i * 4);
699 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
700 	}
701 
702 	ptr = raw_cpu_ptr(gic->saved_ppi_active);
703 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++) {
704 		writel_relaxed(GICD_INT_EN_CLR_X32,
705 			       dist_base + GIC_DIST_ACTIVE_CLEAR + i * 4);
706 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ACTIVE_SET + i * 4);
707 	}
708 
709 	ptr = raw_cpu_ptr(gic->saved_ppi_conf);
710 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
711 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
712 
713 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
714 		writel_relaxed(GICD_INT_DEF_PRI_X4,
715 					dist_base + GIC_DIST_PRI + i * 4);
716 
717 	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
718 	gic_cpu_if_up(gic);
719 }
720 
gic_notifier(struct notifier_block * self,unsigned long cmd,void * v)721 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
722 {
723 	int i;
724 
725 	for (i = 0; i < CONFIG_ARM_GIC_MAX_NR; i++) {
726 #ifdef CONFIG_GIC_NON_BANKED
727 		/* Skip over unused GICs */
728 		if (!gic_data[i].get_base)
729 			continue;
730 #endif
731 		switch (cmd) {
732 		case CPU_PM_ENTER:
733 			gic_cpu_save(&gic_data[i]);
734 			break;
735 		case CPU_PM_ENTER_FAILED:
736 		case CPU_PM_EXIT:
737 			gic_cpu_restore(&gic_data[i]);
738 			break;
739 		case CPU_CLUSTER_PM_ENTER:
740 			gic_dist_save(&gic_data[i]);
741 			break;
742 		case CPU_CLUSTER_PM_ENTER_FAILED:
743 		case CPU_CLUSTER_PM_EXIT:
744 			gic_dist_restore(&gic_data[i]);
745 			break;
746 		}
747 	}
748 
749 	return NOTIFY_OK;
750 }
751 
752 static struct notifier_block gic_notifier_block = {
753 	.notifier_call = gic_notifier,
754 };
755 
gic_pm_init(struct gic_chip_data * gic)756 static int gic_pm_init(struct gic_chip_data *gic)
757 {
758 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
759 		sizeof(u32));
760 	if (WARN_ON(!gic->saved_ppi_enable))
761 		return -ENOMEM;
762 
763 	gic->saved_ppi_active = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
764 		sizeof(u32));
765 	if (WARN_ON(!gic->saved_ppi_active))
766 		goto free_ppi_enable;
767 
768 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
769 		sizeof(u32));
770 	if (WARN_ON(!gic->saved_ppi_conf))
771 		goto free_ppi_active;
772 
773 	if (gic == &gic_data[0])
774 		cpu_pm_register_notifier(&gic_notifier_block);
775 
776 	return 0;
777 
778 free_ppi_active:
779 	free_percpu(gic->saved_ppi_active);
780 free_ppi_enable:
781 	free_percpu(gic->saved_ppi_enable);
782 
783 	return -ENOMEM;
784 }
785 #else
gic_pm_init(struct gic_chip_data * gic)786 static int gic_pm_init(struct gic_chip_data *gic)
787 {
788 	return 0;
789 }
790 #endif
791 
792 #ifdef CONFIG_SMP
gic_raise_softirq(const struct cpumask * mask,unsigned int irq)793 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
794 {
795 	int cpu;
796 	unsigned long flags, map = 0;
797 
798 	if (unlikely(nr_cpu_ids == 1)) {
799 		/* Only one CPU? let's do a self-IPI... */
800 		writel_relaxed(2 << 24 | irq,
801 			       gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
802 		return;
803 	}
804 
805 	gic_lock_irqsave(flags);
806 
807 	/* Convert our logical CPU mask into a physical one. */
808 	for_each_cpu(cpu, mask)
809 		map |= gic_cpu_map[cpu];
810 
811 	/*
812 	 * Ensure that stores to Normal memory are visible to the
813 	 * other CPUs before they observe us issuing the IPI.
814 	 */
815 	dmb(ishst);
816 
817 	/* this always happens on GIC0 */
818 	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
819 
820 	gic_unlock_irqrestore(flags);
821 }
822 #endif
823 
824 #ifdef CONFIG_BL_SWITCHER
825 /*
826  * gic_send_sgi - send a SGI directly to given CPU interface number
827  *
828  * cpu_id: the ID for the destination CPU interface
829  * irq: the IPI number to send a SGI for
830  */
gic_send_sgi(unsigned int cpu_id,unsigned int irq)831 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
832 {
833 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
834 	cpu_id = 1 << cpu_id;
835 	/* this always happens on GIC0 */
836 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
837 }
838 
839 /*
840  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
841  *
842  * @cpu: the logical CPU number to get the GIC ID for.
843  *
844  * Return the CPU interface ID for the given logical CPU number,
845  * or -1 if the CPU number is too large or the interface ID is
846  * unknown (more than one bit set).
847  */
gic_get_cpu_id(unsigned int cpu)848 int gic_get_cpu_id(unsigned int cpu)
849 {
850 	unsigned int cpu_bit;
851 
852 	if (cpu >= NR_GIC_CPU_IF)
853 		return -1;
854 	cpu_bit = gic_cpu_map[cpu];
855 	if (cpu_bit & (cpu_bit - 1))
856 		return -1;
857 	return __ffs(cpu_bit);
858 }
859 
860 /*
861  * gic_migrate_target - migrate IRQs to another CPU interface
862  *
863  * @new_cpu_id: the CPU target ID to migrate IRQs to
864  *
865  * Migrate all peripheral interrupts with a target matching the current CPU
866  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
867  * is also updated.  Targets to other CPU interfaces are unchanged.
868  * This must be called with IRQs locally disabled.
869  */
gic_migrate_target(unsigned int new_cpu_id)870 void gic_migrate_target(unsigned int new_cpu_id)
871 {
872 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
873 	void __iomem *dist_base;
874 	int i, ror_val, cpu = smp_processor_id();
875 	u32 val, cur_target_mask, active_mask;
876 
877 	BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR);
878 
879 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
880 	if (!dist_base)
881 		return;
882 	gic_irqs = gic_data[gic_nr].gic_irqs;
883 
884 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
885 	cur_target_mask = 0x01010101 << cur_cpu_id;
886 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
887 
888 	gic_lock();
889 
890 	/* Update the target interface for this logical CPU */
891 	gic_cpu_map[cpu] = 1 << new_cpu_id;
892 
893 	/*
894 	 * Find all the peripheral interrupts targetting the current
895 	 * CPU interface and migrate them to the new CPU interface.
896 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
897 	 */
898 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
899 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
900 		active_mask = val & cur_target_mask;
901 		if (active_mask) {
902 			val &= ~active_mask;
903 			val |= ror32(active_mask, ror_val);
904 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
905 		}
906 	}
907 
908 	gic_unlock();
909 
910 	/*
911 	 * Now let's migrate and clear any potential SGIs that might be
912 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
913 	 * is a banked register, we can only forward the SGI using
914 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
915 	 * doesn't use that information anyway.
916 	 *
917 	 * For the same reason we do not adjust SGI source information
918 	 * for previously sent SGIs by us to other CPUs either.
919 	 */
920 	for (i = 0; i < 16; i += 4) {
921 		int j;
922 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
923 		if (!val)
924 			continue;
925 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
926 		for (j = i; j < i + 4; j++) {
927 			if (val & 0xff)
928 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
929 						dist_base + GIC_DIST_SOFTINT);
930 			val >>= 8;
931 		}
932 	}
933 }
934 
935 /*
936  * gic_get_sgir_physaddr - get the physical address for the SGI register
937  *
938  * REturn the physical address of the SGI register to be used
939  * by some early assembly code when the kernel is not yet available.
940  */
941 static unsigned long gic_dist_physaddr;
942 
gic_get_sgir_physaddr(void)943 unsigned long gic_get_sgir_physaddr(void)
944 {
945 	if (!gic_dist_physaddr)
946 		return 0;
947 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
948 }
949 
gic_init_physaddr(struct device_node * node)950 static void __init gic_init_physaddr(struct device_node *node)
951 {
952 	struct resource res;
953 	if (of_address_to_resource(node, 0, &res) == 0) {
954 		gic_dist_physaddr = res.start;
955 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
956 	}
957 }
958 
959 #else
960 #define gic_init_physaddr(node)  do { } while (0)
961 #endif
962 
gic_irq_domain_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hw)963 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
964 				irq_hw_number_t hw)
965 {
966 	struct gic_chip_data *gic = d->host_data;
967 
968 	if (hw < 32) {
969 		irq_set_percpu_devid(irq);
970 		irq_domain_set_info(d, irq, hw, &gic->chip, d->host_data,
971 				    handle_percpu_devid_irq, NULL, NULL);
972 		irq_set_status_flags(irq, IRQ_NOAUTOEN);
973 	} else {
974 		irq_domain_set_info(d, irq, hw, &gic->chip, d->host_data,
975 				    handle_fasteoi_irq, NULL, NULL);
976 		irq_set_probe(irq);
977 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
978 	}
979 	return 0;
980 }
981 
gic_irq_domain_unmap(struct irq_domain * d,unsigned int irq)982 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
983 {
984 }
985 
gic_irq_domain_translate(struct irq_domain * d,struct irq_fwspec * fwspec,unsigned long * hwirq,unsigned int * type)986 static int gic_irq_domain_translate(struct irq_domain *d,
987 				    struct irq_fwspec *fwspec,
988 				    unsigned long *hwirq,
989 				    unsigned int *type)
990 {
991 	if (is_of_node(fwspec->fwnode)) {
992 		if (fwspec->param_count < 3)
993 			return -EINVAL;
994 
995 		/* Get the interrupt number and add 16 to skip over SGIs */
996 		*hwirq = fwspec->param[1] + 16;
997 
998 		/*
999 		 * For SPIs, we need to add 16 more to get the GIC irq
1000 		 * ID number
1001 		 */
1002 		if (!fwspec->param[0])
1003 			*hwirq += 16;
1004 
1005 		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
1006 
1007 		/* Make it clear that broken DTs are... broken */
1008 		WARN_ON(*type == IRQ_TYPE_NONE);
1009 		return 0;
1010 	}
1011 
1012 	if (is_fwnode_irqchip(fwspec->fwnode)) {
1013 		if(fwspec->param_count != 2)
1014 			return -EINVAL;
1015 
1016 		*hwirq = fwspec->param[0];
1017 		*type = fwspec->param[1];
1018 
1019 		WARN_ON(*type == IRQ_TYPE_NONE);
1020 		return 0;
1021 	}
1022 
1023 	return -EINVAL;
1024 }
1025 
gic_starting_cpu(unsigned int cpu)1026 static int gic_starting_cpu(unsigned int cpu)
1027 {
1028 	gic_cpu_init(&gic_data[0]);
1029 	return 0;
1030 }
1031 
gic_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)1032 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
1033 				unsigned int nr_irqs, void *arg)
1034 {
1035 	int i, ret;
1036 	irq_hw_number_t hwirq;
1037 	unsigned int type = IRQ_TYPE_NONE;
1038 	struct irq_fwspec *fwspec = arg;
1039 
1040 	ret = gic_irq_domain_translate(domain, fwspec, &hwirq, &type);
1041 	if (ret)
1042 		return ret;
1043 
1044 	for (i = 0; i < nr_irqs; i++) {
1045 		ret = gic_irq_domain_map(domain, virq + i, hwirq + i);
1046 		if (ret)
1047 			return ret;
1048 	}
1049 
1050 	return 0;
1051 }
1052 
1053 static const struct irq_domain_ops gic_irq_domain_hierarchy_ops = {
1054 	.translate = gic_irq_domain_translate,
1055 	.alloc = gic_irq_domain_alloc,
1056 	.free = irq_domain_free_irqs_top,
1057 };
1058 
1059 static const struct irq_domain_ops gic_irq_domain_ops = {
1060 	.map = gic_irq_domain_map,
1061 	.unmap = gic_irq_domain_unmap,
1062 };
1063 
gic_init_chip(struct gic_chip_data * gic,struct device * dev,const char * name,bool use_eoimode1)1064 static void gic_init_chip(struct gic_chip_data *gic, struct device *dev,
1065 			  const char *name, bool use_eoimode1)
1066 {
1067 	/* Initialize irq_chip */
1068 	gic->chip = gic_chip;
1069 	gic->chip.name = name;
1070 	gic->chip.parent_device = dev;
1071 
1072 	if (use_eoimode1) {
1073 		gic->chip.irq_mask = gic_eoimode1_mask_irq;
1074 		gic->chip.irq_eoi = gic_eoimode1_eoi_irq;
1075 		gic->chip.irq_set_vcpu_affinity = gic_irq_set_vcpu_affinity;
1076 	}
1077 
1078 #ifdef CONFIG_SMP
1079 	if (gic == &gic_data[0])
1080 		gic->chip.irq_set_affinity = gic_set_affinity;
1081 #endif
1082 }
1083 
gic_init_bases(struct gic_chip_data * gic,int irq_start,struct fwnode_handle * handle)1084 static int gic_init_bases(struct gic_chip_data *gic, int irq_start,
1085 			  struct fwnode_handle *handle)
1086 {
1087 	irq_hw_number_t hwirq_base;
1088 	int gic_irqs, irq_base, ret;
1089 
1090 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1091 		/* Frankein-GIC without banked registers... */
1092 		unsigned int cpu;
1093 
1094 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
1095 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
1096 		if (WARN_ON(!gic->dist_base.percpu_base ||
1097 			    !gic->cpu_base.percpu_base)) {
1098 			ret = -ENOMEM;
1099 			goto error;
1100 		}
1101 
1102 		for_each_possible_cpu(cpu) {
1103 			u32 mpidr = cpu_logical_map(cpu);
1104 			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
1105 			unsigned long offset = gic->percpu_offset * core_id;
1106 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) =
1107 				gic->raw_dist_base + offset;
1108 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) =
1109 				gic->raw_cpu_base + offset;
1110 		}
1111 
1112 		gic_set_base_accessor(gic, gic_get_percpu_base);
1113 	} else {
1114 		/* Normal, sane GIC... */
1115 		WARN(gic->percpu_offset,
1116 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
1117 		     gic->percpu_offset);
1118 		gic->dist_base.common_base = gic->raw_dist_base;
1119 		gic->cpu_base.common_base = gic->raw_cpu_base;
1120 		gic_set_base_accessor(gic, gic_get_common_base);
1121 	}
1122 
1123 	/*
1124 	 * Find out how many interrupts are supported.
1125 	 * The GIC only supports up to 1020 interrupt sources.
1126 	 */
1127 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
1128 	gic_irqs = (gic_irqs + 1) * 32;
1129 	if (gic_irqs > 1020)
1130 		gic_irqs = 1020;
1131 	gic->gic_irqs = gic_irqs;
1132 
1133 	if (handle) {		/* DT/ACPI */
1134 		gic->domain = irq_domain_create_linear(handle, gic_irqs,
1135 						       &gic_irq_domain_hierarchy_ops,
1136 						       gic);
1137 	} else {		/* Legacy support */
1138 		/*
1139 		 * For primary GICs, skip over SGIs.
1140 		 * For secondary GICs, skip over PPIs, too.
1141 		 */
1142 		if (gic == &gic_data[0] && (irq_start & 31) > 0) {
1143 			hwirq_base = 16;
1144 			if (irq_start != -1)
1145 				irq_start = (irq_start & ~31) + 16;
1146 		} else {
1147 			hwirq_base = 32;
1148 		}
1149 
1150 		gic_irqs -= hwirq_base; /* calculate # of irqs to allocate */
1151 
1152 		irq_base = irq_alloc_descs(irq_start, 16, gic_irqs,
1153 					   numa_node_id());
1154 		if (irq_base < 0) {
1155 			WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
1156 			     irq_start);
1157 			irq_base = irq_start;
1158 		}
1159 
1160 		gic->domain = irq_domain_add_legacy(NULL, gic_irqs, irq_base,
1161 					hwirq_base, &gic_irq_domain_ops, gic);
1162 	}
1163 
1164 	if (WARN_ON(!gic->domain)) {
1165 		ret = -ENODEV;
1166 		goto error;
1167 	}
1168 
1169 	gic_dist_init(gic);
1170 	ret = gic_cpu_init(gic);
1171 	if (ret)
1172 		goto error;
1173 
1174 	ret = gic_pm_init(gic);
1175 	if (ret)
1176 		goto error;
1177 
1178 	return 0;
1179 
1180 error:
1181 	if (IS_ENABLED(CONFIG_GIC_NON_BANKED) && gic->percpu_offset) {
1182 		free_percpu(gic->dist_base.percpu_base);
1183 		free_percpu(gic->cpu_base.percpu_base);
1184 	}
1185 
1186 	return ret;
1187 }
1188 
__gic_init_bases(struct gic_chip_data * gic,int irq_start,struct fwnode_handle * handle)1189 static int __init __gic_init_bases(struct gic_chip_data *gic,
1190 				   int irq_start,
1191 				   struct fwnode_handle *handle)
1192 {
1193 	char *name;
1194 	int i, ret;
1195 
1196 	if (WARN_ON(!gic || gic->domain))
1197 		return -EINVAL;
1198 
1199 	if (gic == &gic_data[0]) {
1200 		/*
1201 		 * Initialize the CPU interface map to all CPUs.
1202 		 * It will be refined as each CPU probes its ID.
1203 		 * This is only necessary for the primary GIC.
1204 		 */
1205 		for (i = 0; i < NR_GIC_CPU_IF; i++)
1206 			gic_cpu_map[i] = 0xff;
1207 #ifdef CONFIG_SMP
1208 		set_smp_cross_call(gic_raise_softirq);
1209 #endif
1210 		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GIC_STARTING,
1211 					  "irqchip/arm/gic:starting",
1212 					  gic_starting_cpu, NULL);
1213 		set_handle_irq(gic_handle_irq);
1214 		if (static_branch_likely(&supports_deactivate_key))
1215 			pr_info("GIC: Using split EOI/Deactivate mode\n");
1216 	}
1217 
1218 	if (static_branch_likely(&supports_deactivate_key) && gic == &gic_data[0]) {
1219 		name = kasprintf(GFP_KERNEL, "GICv2");
1220 		gic_init_chip(gic, NULL, name, true);
1221 	} else {
1222 		name = kasprintf(GFP_KERNEL, "GIC-%d", (int)(gic-&gic_data[0]));
1223 		gic_init_chip(gic, NULL, name, false);
1224 	}
1225 
1226 	ret = gic_init_bases(gic, irq_start, handle);
1227 	if (ret)
1228 		kfree(name);
1229 
1230 	return ret;
1231 }
1232 
gic_init(unsigned int gic_nr,int irq_start,void __iomem * dist_base,void __iomem * cpu_base)1233 void __init gic_init(unsigned int gic_nr, int irq_start,
1234 		     void __iomem *dist_base, void __iomem *cpu_base)
1235 {
1236 	struct gic_chip_data *gic;
1237 
1238 	if (WARN_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR))
1239 		return;
1240 
1241 	/*
1242 	 * Non-DT/ACPI systems won't run a hypervisor, so let's not
1243 	 * bother with these...
1244 	 */
1245 	static_branch_disable(&supports_deactivate_key);
1246 
1247 	gic = &gic_data[gic_nr];
1248 	gic->raw_dist_base = dist_base;
1249 	gic->raw_cpu_base = cpu_base;
1250 
1251 	__gic_init_bases(gic, irq_start, NULL);
1252 }
1253 
gic_teardown(struct gic_chip_data * gic)1254 static void gic_teardown(struct gic_chip_data *gic)
1255 {
1256 	if (WARN_ON(!gic))
1257 		return;
1258 
1259 	if (gic->raw_dist_base)
1260 		iounmap(gic->raw_dist_base);
1261 	if (gic->raw_cpu_base)
1262 		iounmap(gic->raw_cpu_base);
1263 }
1264 
1265 #ifdef CONFIG_OF
1266 static int gic_cnt __initdata;
1267 static bool gicv2_force_probe;
1268 
gicv2_force_probe_cfg(char * buf)1269 static int __init gicv2_force_probe_cfg(char *buf)
1270 {
1271 	return strtobool(buf, &gicv2_force_probe);
1272 }
1273 early_param("irqchip.gicv2_force_probe", gicv2_force_probe_cfg);
1274 
gic_check_eoimode(struct device_node * node,void __iomem ** base)1275 static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
1276 {
1277 	struct resource cpuif_res;
1278 
1279 	of_address_to_resource(node, 1, &cpuif_res);
1280 
1281 	if (!is_hyp_mode_available())
1282 		return false;
1283 	if (resource_size(&cpuif_res) < SZ_8K) {
1284 		void __iomem *alt;
1285 		/*
1286 		 * Check for a stupid firmware that only exposes the
1287 		 * first page of a GICv2.
1288 		 */
1289 		if (!gic_check_gicv2(*base))
1290 			return false;
1291 
1292 		if (!gicv2_force_probe) {
1293 			pr_warn("GIC: GICv2 detected, but range too small and irqchip.gicv2_force_probe not set\n");
1294 			return false;
1295 		}
1296 
1297 		alt = ioremap(cpuif_res.start, SZ_8K);
1298 		if (!alt)
1299 			return false;
1300 		if (!gic_check_gicv2(alt + SZ_4K)) {
1301 			/*
1302 			 * The first page was that of a GICv2, and
1303 			 * the second was *something*. Let's trust it
1304 			 * to be a GICv2, and update the mapping.
1305 			 */
1306 			pr_warn("GIC: GICv2 at %pa, but range is too small (broken DT?), assuming 8kB\n",
1307 				&cpuif_res.start);
1308 			iounmap(*base);
1309 			*base = alt;
1310 			return true;
1311 		}
1312 
1313 		/*
1314 		 * We detected *two* initial GICv2 pages in a
1315 		 * row. Could be a GICv2 aliased over two 64kB
1316 		 * pages. Update the resource, map the iospace, and
1317 		 * pray.
1318 		 */
1319 		iounmap(alt);
1320 		alt = ioremap(cpuif_res.start, SZ_128K);
1321 		if (!alt)
1322 			return false;
1323 		pr_warn("GIC: Aliased GICv2 at %pa, trying to find the canonical range over 128kB\n",
1324 			&cpuif_res.start);
1325 		cpuif_res.end = cpuif_res.start + SZ_128K -1;
1326 		iounmap(*base);
1327 		*base = alt;
1328 	}
1329 	if (resource_size(&cpuif_res) == SZ_128K) {
1330 		/*
1331 		 * Verify that we have the first 4kB of a GICv2
1332 		 * aliased over the first 64kB by checking the
1333 		 * GICC_IIDR register on both ends.
1334 		 */
1335 		if (!gic_check_gicv2(*base) ||
1336 		    !gic_check_gicv2(*base + 0xf000))
1337 			return false;
1338 
1339 		/*
1340 		 * Move the base up by 60kB, so that we have a 8kB
1341 		 * contiguous region, which allows us to use GICC_DIR
1342 		 * at its normal offset. Please pass me that bucket.
1343 		 */
1344 		*base += 0xf000;
1345 		cpuif_res.start += 0xf000;
1346 		pr_warn("GIC: Adjusting CPU interface base to %pa\n",
1347 			&cpuif_res.start);
1348 	}
1349 
1350 	return true;
1351 }
1352 
gic_of_setup(struct gic_chip_data * gic,struct device_node * node)1353 static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
1354 {
1355 	if (!gic || !node)
1356 		return -EINVAL;
1357 
1358 	gic->raw_dist_base = of_iomap(node, 0);
1359 	if (WARN(!gic->raw_dist_base, "unable to map gic dist registers\n"))
1360 		goto error;
1361 
1362 	gic->raw_cpu_base = of_iomap(node, 1);
1363 	if (WARN(!gic->raw_cpu_base, "unable to map gic cpu registers\n"))
1364 		goto error;
1365 
1366 	if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
1367 		gic->percpu_offset = 0;
1368 
1369 	return 0;
1370 
1371 error:
1372 	gic_teardown(gic);
1373 
1374 	return -ENOMEM;
1375 }
1376 
gic_of_init_child(struct device * dev,struct gic_chip_data ** gic,int irq)1377 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1378 {
1379 	int ret;
1380 
1381 	if (!dev || !dev->of_node || !gic || !irq)
1382 		return -EINVAL;
1383 
1384 	*gic = devm_kzalloc(dev, sizeof(**gic), GFP_KERNEL);
1385 	if (!*gic)
1386 		return -ENOMEM;
1387 
1388 	gic_init_chip(*gic, dev, dev->of_node->name, false);
1389 
1390 	ret = gic_of_setup(*gic, dev->of_node);
1391 	if (ret)
1392 		return ret;
1393 
1394 	ret = gic_init_bases(*gic, -1, &dev->of_node->fwnode);
1395 	if (ret) {
1396 		gic_teardown(*gic);
1397 		return ret;
1398 	}
1399 
1400 	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq, *gic);
1401 
1402 	return 0;
1403 }
1404 
gic_of_setup_kvm_info(struct device_node * node)1405 static void __init gic_of_setup_kvm_info(struct device_node *node)
1406 {
1407 	int ret;
1408 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1409 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1410 
1411 	gic_v2_kvm_info.type = GIC_V2;
1412 
1413 	gic_v2_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
1414 	if (!gic_v2_kvm_info.maint_irq)
1415 		return;
1416 
1417 	ret = of_address_to_resource(node, 2, vctrl_res);
1418 	if (ret)
1419 		return;
1420 
1421 	ret = of_address_to_resource(node, 3, vcpu_res);
1422 	if (ret)
1423 		return;
1424 
1425 	if (static_branch_likely(&supports_deactivate_key))
1426 		gic_set_kvm_info(&gic_v2_kvm_info);
1427 }
1428 
1429 int __init
gic_of_init(struct device_node * node,struct device_node * parent)1430 gic_of_init(struct device_node *node, struct device_node *parent)
1431 {
1432 	struct gic_chip_data *gic;
1433 	int irq, ret;
1434 
1435 	if (WARN_ON(!node))
1436 		return -ENODEV;
1437 
1438 	if (WARN_ON(gic_cnt >= CONFIG_ARM_GIC_MAX_NR))
1439 		return -EINVAL;
1440 
1441 	gic = &gic_data[gic_cnt];
1442 
1443 	ret = gic_of_setup(gic, node);
1444 	if (ret)
1445 		return ret;
1446 
1447 	/*
1448 	 * Disable split EOI/Deactivate if either HYP is not available
1449 	 * or the CPU interface is too small.
1450 	 */
1451 	if (gic_cnt == 0 && !gic_check_eoimode(node, &gic->raw_cpu_base))
1452 		static_branch_disable(&supports_deactivate_key);
1453 
1454 	ret = __gic_init_bases(gic, -1, &node->fwnode);
1455 	if (ret) {
1456 		gic_teardown(gic);
1457 		return ret;
1458 	}
1459 
1460 	if (!gic_cnt) {
1461 		gic_init_physaddr(node);
1462 		gic_of_setup_kvm_info(node);
1463 	}
1464 
1465 	if (parent) {
1466 		irq = irq_of_parse_and_map(node, 0);
1467 		gic_cascade_irq(gic_cnt, irq);
1468 	}
1469 
1470 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1471 		gicv2m_init(&node->fwnode, gic_data[gic_cnt].domain);
1472 
1473 	gic_cnt++;
1474 	return 0;
1475 }
1476 IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1477 IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
1478 IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
1479 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1480 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1481 IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1482 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1483 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1484 IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init);
1485 #else
gic_of_init_child(struct device * dev,struct gic_chip_data ** gic,int irq)1486 int gic_of_init_child(struct device *dev, struct gic_chip_data **gic, int irq)
1487 {
1488 	return -ENOTSUPP;
1489 }
1490 #endif
1491 
1492 #ifdef CONFIG_ACPI
1493 static struct
1494 {
1495 	phys_addr_t cpu_phys_base;
1496 	u32 maint_irq;
1497 	int maint_irq_mode;
1498 	phys_addr_t vctrl_base;
1499 	phys_addr_t vcpu_base;
1500 } acpi_data __initdata;
1501 
1502 static int __init
gic_acpi_parse_madt_cpu(struct acpi_subtable_header * header,const unsigned long end)1503 gic_acpi_parse_madt_cpu(struct acpi_subtable_header *header,
1504 			const unsigned long end)
1505 {
1506 	struct acpi_madt_generic_interrupt *processor;
1507 	phys_addr_t gic_cpu_base;
1508 	static int cpu_base_assigned;
1509 
1510 	processor = (struct acpi_madt_generic_interrupt *)header;
1511 
1512 	if (BAD_MADT_GICC_ENTRY(processor, end))
1513 		return -EINVAL;
1514 
1515 	/*
1516 	 * There is no support for non-banked GICv1/2 register in ACPI spec.
1517 	 * All CPU interface addresses have to be the same.
1518 	 */
1519 	gic_cpu_base = processor->base_address;
1520 	if (cpu_base_assigned && gic_cpu_base != acpi_data.cpu_phys_base)
1521 		return -EINVAL;
1522 
1523 	acpi_data.cpu_phys_base = gic_cpu_base;
1524 	acpi_data.maint_irq = processor->vgic_interrupt;
1525 	acpi_data.maint_irq_mode = (processor->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
1526 				    ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
1527 	acpi_data.vctrl_base = processor->gich_base_address;
1528 	acpi_data.vcpu_base = processor->gicv_base_address;
1529 
1530 	cpu_base_assigned = 1;
1531 	return 0;
1532 }
1533 
1534 /* The things you have to do to just *count* something... */
acpi_dummy_func(struct acpi_subtable_header * header,const unsigned long end)1535 static int __init acpi_dummy_func(struct acpi_subtable_header *header,
1536 				  const unsigned long end)
1537 {
1538 	return 0;
1539 }
1540 
acpi_gic_redist_is_present(void)1541 static bool __init acpi_gic_redist_is_present(void)
1542 {
1543 	return acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
1544 				     acpi_dummy_func, 0) > 0;
1545 }
1546 
gic_validate_dist(struct acpi_subtable_header * header,struct acpi_probe_entry * ape)1547 static bool __init gic_validate_dist(struct acpi_subtable_header *header,
1548 				     struct acpi_probe_entry *ape)
1549 {
1550 	struct acpi_madt_generic_distributor *dist;
1551 	dist = (struct acpi_madt_generic_distributor *)header;
1552 
1553 	return (dist->version == ape->driver_data &&
1554 		(dist->version != ACPI_MADT_GIC_VERSION_NONE ||
1555 		 !acpi_gic_redist_is_present()));
1556 }
1557 
1558 #define ACPI_GICV2_DIST_MEM_SIZE	(SZ_4K)
1559 #define ACPI_GIC_CPU_IF_MEM_SIZE	(SZ_8K)
1560 #define ACPI_GICV2_VCTRL_MEM_SIZE	(SZ_4K)
1561 #define ACPI_GICV2_VCPU_MEM_SIZE	(SZ_8K)
1562 
gic_acpi_setup_kvm_info(void)1563 static void __init gic_acpi_setup_kvm_info(void)
1564 {
1565 	int irq;
1566 	struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
1567 	struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
1568 
1569 	gic_v2_kvm_info.type = GIC_V2;
1570 
1571 	if (!acpi_data.vctrl_base)
1572 		return;
1573 
1574 	vctrl_res->flags = IORESOURCE_MEM;
1575 	vctrl_res->start = acpi_data.vctrl_base;
1576 	vctrl_res->end = vctrl_res->start + ACPI_GICV2_VCTRL_MEM_SIZE - 1;
1577 
1578 	if (!acpi_data.vcpu_base)
1579 		return;
1580 
1581 	vcpu_res->flags = IORESOURCE_MEM;
1582 	vcpu_res->start = acpi_data.vcpu_base;
1583 	vcpu_res->end = vcpu_res->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
1584 
1585 	irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
1586 				acpi_data.maint_irq_mode,
1587 				ACPI_ACTIVE_HIGH);
1588 	if (irq <= 0)
1589 		return;
1590 
1591 	gic_v2_kvm_info.maint_irq = irq;
1592 
1593 	gic_set_kvm_info(&gic_v2_kvm_info);
1594 }
1595 
gic_v2_acpi_init(struct acpi_subtable_header * header,const unsigned long end)1596 static int __init gic_v2_acpi_init(struct acpi_subtable_header *header,
1597 				   const unsigned long end)
1598 {
1599 	struct acpi_madt_generic_distributor *dist;
1600 	struct fwnode_handle *domain_handle;
1601 	struct gic_chip_data *gic = &gic_data[0];
1602 	int count, ret;
1603 
1604 	/* Collect CPU base addresses */
1605 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
1606 				      gic_acpi_parse_madt_cpu, 0);
1607 	if (count <= 0) {
1608 		pr_err("No valid GICC entries exist\n");
1609 		return -EINVAL;
1610 	}
1611 
1612 	gic->raw_cpu_base = ioremap(acpi_data.cpu_phys_base, ACPI_GIC_CPU_IF_MEM_SIZE);
1613 	if (!gic->raw_cpu_base) {
1614 		pr_err("Unable to map GICC registers\n");
1615 		return -ENOMEM;
1616 	}
1617 
1618 	dist = (struct acpi_madt_generic_distributor *)header;
1619 	gic->raw_dist_base = ioremap(dist->base_address,
1620 				     ACPI_GICV2_DIST_MEM_SIZE);
1621 	if (!gic->raw_dist_base) {
1622 		pr_err("Unable to map GICD registers\n");
1623 		gic_teardown(gic);
1624 		return -ENOMEM;
1625 	}
1626 
1627 	/*
1628 	 * Disable split EOI/Deactivate if HYP is not available. ACPI
1629 	 * guarantees that we'll always have a GICv2, so the CPU
1630 	 * interface will always be the right size.
1631 	 */
1632 	if (!is_hyp_mode_available())
1633 		static_branch_disable(&supports_deactivate_key);
1634 
1635 	/*
1636 	 * Initialize GIC instance zero (no multi-GIC support).
1637 	 */
1638 	domain_handle = irq_domain_alloc_fwnode(gic->raw_dist_base);
1639 	if (!domain_handle) {
1640 		pr_err("Unable to allocate domain handle\n");
1641 		gic_teardown(gic);
1642 		return -ENOMEM;
1643 	}
1644 
1645 	ret = __gic_init_bases(gic, -1, domain_handle);
1646 	if (ret) {
1647 		pr_err("Failed to initialise GIC\n");
1648 		irq_domain_free_fwnode(domain_handle);
1649 		gic_teardown(gic);
1650 		return ret;
1651 	}
1652 
1653 	acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
1654 
1655 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1656 		gicv2m_init(NULL, gic_data[0].domain);
1657 
1658 	if (static_branch_likely(&supports_deactivate_key))
1659 		gic_acpi_setup_kvm_info();
1660 
1661 	return 0;
1662 }
1663 IRQCHIP_ACPI_DECLARE(gic_v2, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1664 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_V2,
1665 		     gic_v2_acpi_init);
1666 IRQCHIP_ACPI_DECLARE(gic_v2_maybe, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
1667 		     gic_validate_dist, ACPI_MADT_GIC_VERSION_NONE,
1668 		     gic_v2_acpi_init);
1669 #endif
1670