xref: /openbmc/linux/drivers/irqchip/irq-gic.c (revision 5c73cc4b6c83e88863a5de869cc5df3b913aef4a)
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/irqdomain.h>
37 #include <linux/interrupt.h>
38 #include <linux/percpu.h>
39 #include <linux/slab.h>
40 #include <linux/irqchip/chained_irq.h>
41 #include <linux/irqchip/arm-gic.h>
42 
43 #include <asm/cputype.h>
44 #include <asm/irq.h>
45 #include <asm/exception.h>
46 #include <asm/smp_plat.h>
47 
48 #include "irq-gic-common.h"
49 #include "irqchip.h"
50 
51 union gic_base {
52 	void __iomem *common_base;
53 	void __percpu * __iomem *percpu_base;
54 };
55 
56 struct gic_chip_data {
57 	union gic_base dist_base;
58 	union gic_base cpu_base;
59 #ifdef CONFIG_CPU_PM
60 	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
61 	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
62 	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
63 	u32 __percpu *saved_ppi_enable;
64 	u32 __percpu *saved_ppi_conf;
65 #endif
66 	struct irq_domain *domain;
67 	unsigned int gic_irqs;
68 #ifdef CONFIG_GIC_NON_BANKED
69 	void __iomem *(*get_base)(union gic_base *);
70 #endif
71 };
72 
73 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
74 
75 /*
76  * The GIC mapping of CPU interfaces does not necessarily match
77  * the logical CPU numbering.  Let's use a mapping as returned
78  * by the GIC itself.
79  */
80 #define NR_GIC_CPU_IF 8
81 static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
82 
83 /*
84  * Supported arch specific GIC irq extension.
85  * Default make them NULL.
86  */
87 struct irq_chip gic_arch_extn = {
88 	.irq_eoi	= NULL,
89 	.irq_mask	= NULL,
90 	.irq_unmask	= NULL,
91 	.irq_retrigger	= NULL,
92 	.irq_set_type	= NULL,
93 	.irq_set_wake	= NULL,
94 };
95 
96 #ifndef MAX_GIC_NR
97 #define MAX_GIC_NR	1
98 #endif
99 
100 static struct gic_chip_data gic_data[MAX_GIC_NR] __read_mostly;
101 
102 #ifdef CONFIG_GIC_NON_BANKED
103 static void __iomem *gic_get_percpu_base(union gic_base *base)
104 {
105 	return raw_cpu_read(*base->percpu_base);
106 }
107 
108 static void __iomem *gic_get_common_base(union gic_base *base)
109 {
110 	return base->common_base;
111 }
112 
113 static inline void __iomem *gic_data_dist_base(struct gic_chip_data *data)
114 {
115 	return data->get_base(&data->dist_base);
116 }
117 
118 static inline void __iomem *gic_data_cpu_base(struct gic_chip_data *data)
119 {
120 	return data->get_base(&data->cpu_base);
121 }
122 
123 static inline void gic_set_base_accessor(struct gic_chip_data *data,
124 					 void __iomem *(*f)(union gic_base *))
125 {
126 	data->get_base = f;
127 }
128 #else
129 #define gic_data_dist_base(d)	((d)->dist_base.common_base)
130 #define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
131 #define gic_set_base_accessor(d, f)
132 #endif
133 
134 static inline void __iomem *gic_dist_base(struct irq_data *d)
135 {
136 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
137 	return gic_data_dist_base(gic_data);
138 }
139 
140 static inline void __iomem *gic_cpu_base(struct irq_data *d)
141 {
142 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
143 	return gic_data_cpu_base(gic_data);
144 }
145 
146 static inline unsigned int gic_irq(struct irq_data *d)
147 {
148 	return d->hwirq;
149 }
150 
151 /*
152  * Routines to acknowledge, disable and enable interrupts
153  */
154 static void gic_poke_irq(struct irq_data *d, u32 offset)
155 {
156 	u32 mask = 1 << (gic_irq(d) % 32);
157 	writel_relaxed(mask, gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4);
158 }
159 
160 static int gic_peek_irq(struct irq_data *d, u32 offset)
161 {
162 	u32 mask = 1 << (gic_irq(d) % 32);
163 	return !!(readl_relaxed(gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4) & mask);
164 }
165 
166 static void gic_mask_irq(struct irq_data *d)
167 {
168 	unsigned long flags;
169 
170 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
171 	gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
172 	if (gic_arch_extn.irq_mask)
173 		gic_arch_extn.irq_mask(d);
174 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
175 }
176 
177 static void gic_unmask_irq(struct irq_data *d)
178 {
179 	unsigned long flags;
180 
181 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
182 	if (gic_arch_extn.irq_unmask)
183 		gic_arch_extn.irq_unmask(d);
184 	gic_poke_irq(d, GIC_DIST_ENABLE_SET);
185 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
186 }
187 
188 static void gic_eoi_irq(struct irq_data *d)
189 {
190 	if (gic_arch_extn.irq_eoi) {
191 		raw_spin_lock(&irq_controller_lock);
192 		gic_arch_extn.irq_eoi(d);
193 		raw_spin_unlock(&irq_controller_lock);
194 	}
195 
196 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
197 }
198 
199 static int gic_irq_set_irqchip_state(struct irq_data *d,
200 				     enum irqchip_irq_state which, bool val)
201 {
202 	u32 reg;
203 
204 	switch (which) {
205 	case IRQCHIP_STATE_PENDING:
206 		reg = val ? GIC_DIST_PENDING_SET : GIC_DIST_PENDING_CLEAR;
207 		break;
208 
209 	case IRQCHIP_STATE_ACTIVE:
210 		reg = val ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR;
211 		break;
212 
213 	case IRQCHIP_STATE_MASKED:
214 		reg = val ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET;
215 		break;
216 
217 	default:
218 		return -EINVAL;
219 	}
220 
221 	gic_poke_irq(d, reg);
222 	return 0;
223 }
224 
225 static int gic_irq_get_irqchip_state(struct irq_data *d,
226 				      enum irqchip_irq_state which, bool *val)
227 {
228 	switch (which) {
229 	case IRQCHIP_STATE_PENDING:
230 		*val = gic_peek_irq(d, GIC_DIST_PENDING_SET);
231 		break;
232 
233 	case IRQCHIP_STATE_ACTIVE:
234 		*val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET);
235 		break;
236 
237 	case IRQCHIP_STATE_MASKED:
238 		*val = !gic_peek_irq(d, GIC_DIST_ENABLE_SET);
239 		break;
240 
241 	default:
242 		return -EINVAL;
243 	}
244 
245 	return 0;
246 }
247 
248 static int gic_set_type(struct irq_data *d, unsigned int type)
249 {
250 	void __iomem *base = gic_dist_base(d);
251 	unsigned int gicirq = gic_irq(d);
252 	unsigned long flags;
253 	int ret;
254 
255 	/* Interrupt configuration for SGIs can't be changed */
256 	if (gicirq < 16)
257 		return -EINVAL;
258 
259 	/* SPIs have restrictions on the supported types */
260 	if (gicirq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
261 			    type != IRQ_TYPE_EDGE_RISING)
262 		return -EINVAL;
263 
264 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
265 
266 	if (gic_arch_extn.irq_set_type)
267 		gic_arch_extn.irq_set_type(d, type);
268 
269 	ret = gic_configure_irq(gicirq, type, base, NULL);
270 
271 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
272 
273 	return ret;
274 }
275 
276 static int gic_retrigger(struct irq_data *d)
277 {
278 	if (gic_arch_extn.irq_retrigger)
279 		return gic_arch_extn.irq_retrigger(d);
280 
281 	/* the genirq layer expects 0 if we can't retrigger in hardware */
282 	return 0;
283 }
284 
285 #ifdef CONFIG_SMP
286 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
287 			    bool force)
288 {
289 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
290 	unsigned int cpu, shift = (gic_irq(d) % 4) * 8;
291 	u32 val, mask, bit;
292 	unsigned long flags;
293 
294 	if (!force)
295 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
296 	else
297 		cpu = cpumask_first(mask_val);
298 
299 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
300 		return -EINVAL;
301 
302 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
303 	mask = 0xff << shift;
304 	bit = gic_cpu_map[cpu] << shift;
305 	val = readl_relaxed(reg) & ~mask;
306 	writel_relaxed(val | bit, reg);
307 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
308 
309 	return IRQ_SET_MASK_OK;
310 }
311 #endif
312 
313 #ifdef CONFIG_PM
314 static int gic_set_wake(struct irq_data *d, unsigned int on)
315 {
316 	int ret = -ENXIO;
317 
318 	if (gic_arch_extn.irq_set_wake)
319 		ret = gic_arch_extn.irq_set_wake(d, on);
320 
321 	return ret;
322 }
323 
324 #else
325 #define gic_set_wake	NULL
326 #endif
327 
328 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
329 {
330 	u32 irqstat, irqnr;
331 	struct gic_chip_data *gic = &gic_data[0];
332 	void __iomem *cpu_base = gic_data_cpu_base(gic);
333 
334 	do {
335 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
336 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
337 
338 		if (likely(irqnr > 15 && irqnr < 1021)) {
339 			handle_domain_irq(gic->domain, irqnr, regs);
340 			continue;
341 		}
342 		if (irqnr < 16) {
343 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
344 #ifdef CONFIG_SMP
345 			handle_IPI(irqnr, regs);
346 #endif
347 			continue;
348 		}
349 		break;
350 	} while (1);
351 }
352 
353 static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
354 {
355 	struct gic_chip_data *chip_data = irq_get_handler_data(irq);
356 	struct irq_chip *chip = irq_get_chip(irq);
357 	unsigned int cascade_irq, gic_irq;
358 	unsigned long status;
359 
360 	chained_irq_enter(chip, desc);
361 
362 	raw_spin_lock(&irq_controller_lock);
363 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
364 	raw_spin_unlock(&irq_controller_lock);
365 
366 	gic_irq = (status & GICC_IAR_INT_ID_MASK);
367 	if (gic_irq == GICC_INT_SPURIOUS)
368 		goto out;
369 
370 	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
371 	if (unlikely(gic_irq < 32 || gic_irq > 1020))
372 		handle_bad_irq(cascade_irq, desc);
373 	else
374 		generic_handle_irq(cascade_irq);
375 
376  out:
377 	chained_irq_exit(chip, desc);
378 }
379 
380 static struct irq_chip gic_chip = {
381 	.name			= "GIC",
382 	.irq_mask		= gic_mask_irq,
383 	.irq_unmask		= gic_unmask_irq,
384 	.irq_eoi		= gic_eoi_irq,
385 	.irq_set_type		= gic_set_type,
386 	.irq_retrigger		= gic_retrigger,
387 #ifdef CONFIG_SMP
388 	.irq_set_affinity	= gic_set_affinity,
389 #endif
390 	.irq_set_wake		= gic_set_wake,
391 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
392 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
393 };
394 
395 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
396 {
397 	if (gic_nr >= MAX_GIC_NR)
398 		BUG();
399 	if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
400 		BUG();
401 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
402 }
403 
404 static u8 gic_get_cpumask(struct gic_chip_data *gic)
405 {
406 	void __iomem *base = gic_data_dist_base(gic);
407 	u32 mask, i;
408 
409 	for (i = mask = 0; i < 32; i += 4) {
410 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
411 		mask |= mask >> 16;
412 		mask |= mask >> 8;
413 		if (mask)
414 			break;
415 	}
416 
417 	if (!mask && num_possible_cpus() > 1)
418 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
419 
420 	return mask;
421 }
422 
423 static void gic_cpu_if_up(void)
424 {
425 	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
426 	u32 bypass = 0;
427 
428 	/*
429 	* Preserve bypass disable bits to be written back later
430 	*/
431 	bypass = readl(cpu_base + GIC_CPU_CTRL);
432 	bypass &= GICC_DIS_BYPASS_MASK;
433 
434 	writel_relaxed(bypass | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
435 }
436 
437 
438 static void __init gic_dist_init(struct gic_chip_data *gic)
439 {
440 	unsigned int i;
441 	u32 cpumask;
442 	unsigned int gic_irqs = gic->gic_irqs;
443 	void __iomem *base = gic_data_dist_base(gic);
444 
445 	writel_relaxed(GICD_DISABLE, base + GIC_DIST_CTRL);
446 
447 	/*
448 	 * Set all global interrupts to this CPU only.
449 	 */
450 	cpumask = gic_get_cpumask(gic);
451 	cpumask |= cpumask << 8;
452 	cpumask |= cpumask << 16;
453 	for (i = 32; i < gic_irqs; i += 4)
454 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
455 
456 	gic_dist_config(base, gic_irqs, NULL);
457 
458 	writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL);
459 }
460 
461 static void gic_cpu_init(struct gic_chip_data *gic)
462 {
463 	void __iomem *dist_base = gic_data_dist_base(gic);
464 	void __iomem *base = gic_data_cpu_base(gic);
465 	unsigned int cpu_mask, cpu = smp_processor_id();
466 	int i;
467 
468 	/*
469 	 * Get what the GIC says our CPU mask is.
470 	 */
471 	BUG_ON(cpu >= NR_GIC_CPU_IF);
472 	cpu_mask = gic_get_cpumask(gic);
473 	gic_cpu_map[cpu] = cpu_mask;
474 
475 	/*
476 	 * Clear our mask from the other map entries in case they're
477 	 * still undefined.
478 	 */
479 	for (i = 0; i < NR_GIC_CPU_IF; i++)
480 		if (i != cpu)
481 			gic_cpu_map[i] &= ~cpu_mask;
482 
483 	gic_cpu_config(dist_base, NULL);
484 
485 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
486 	gic_cpu_if_up();
487 }
488 
489 void gic_cpu_if_down(void)
490 {
491 	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
492 	u32 val = 0;
493 
494 	val = readl(cpu_base + GIC_CPU_CTRL);
495 	val &= ~GICC_ENABLE;
496 	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
497 }
498 
499 #ifdef CONFIG_CPU_PM
500 /*
501  * Saves the GIC distributor registers during suspend or idle.  Must be called
502  * with interrupts disabled but before powering down the GIC.  After calling
503  * this function, no interrupts will be delivered by the GIC, and another
504  * platform-specific wakeup source must be enabled.
505  */
506 static void gic_dist_save(unsigned int gic_nr)
507 {
508 	unsigned int gic_irqs;
509 	void __iomem *dist_base;
510 	int i;
511 
512 	if (gic_nr >= MAX_GIC_NR)
513 		BUG();
514 
515 	gic_irqs = gic_data[gic_nr].gic_irqs;
516 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
517 
518 	if (!dist_base)
519 		return;
520 
521 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
522 		gic_data[gic_nr].saved_spi_conf[i] =
523 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
524 
525 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
526 		gic_data[gic_nr].saved_spi_target[i] =
527 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
528 
529 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
530 		gic_data[gic_nr].saved_spi_enable[i] =
531 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
532 }
533 
534 /*
535  * Restores the GIC distributor registers during resume or when coming out of
536  * idle.  Must be called before enabling interrupts.  If a level interrupt
537  * that occured while the GIC was suspended is still present, it will be
538  * handled normally, but any edge interrupts that occured will not be seen by
539  * the GIC and need to be handled by the platform-specific wakeup source.
540  */
541 static void gic_dist_restore(unsigned int gic_nr)
542 {
543 	unsigned int gic_irqs;
544 	unsigned int i;
545 	void __iomem *dist_base;
546 
547 	if (gic_nr >= MAX_GIC_NR)
548 		BUG();
549 
550 	gic_irqs = gic_data[gic_nr].gic_irqs;
551 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
552 
553 	if (!dist_base)
554 		return;
555 
556 	writel_relaxed(GICD_DISABLE, dist_base + GIC_DIST_CTRL);
557 
558 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
559 		writel_relaxed(gic_data[gic_nr].saved_spi_conf[i],
560 			dist_base + GIC_DIST_CONFIG + i * 4);
561 
562 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
563 		writel_relaxed(GICD_INT_DEF_PRI_X4,
564 			dist_base + GIC_DIST_PRI + i * 4);
565 
566 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
567 		writel_relaxed(gic_data[gic_nr].saved_spi_target[i],
568 			dist_base + GIC_DIST_TARGET + i * 4);
569 
570 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
571 		writel_relaxed(gic_data[gic_nr].saved_spi_enable[i],
572 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
573 
574 	writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL);
575 }
576 
577 static void gic_cpu_save(unsigned int gic_nr)
578 {
579 	int i;
580 	u32 *ptr;
581 	void __iomem *dist_base;
582 	void __iomem *cpu_base;
583 
584 	if (gic_nr >= MAX_GIC_NR)
585 		BUG();
586 
587 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
588 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
589 
590 	if (!dist_base || !cpu_base)
591 		return;
592 
593 	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
594 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
595 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
596 
597 	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
598 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
599 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
600 
601 }
602 
603 static void gic_cpu_restore(unsigned int gic_nr)
604 {
605 	int i;
606 	u32 *ptr;
607 	void __iomem *dist_base;
608 	void __iomem *cpu_base;
609 
610 	if (gic_nr >= MAX_GIC_NR)
611 		BUG();
612 
613 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
614 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
615 
616 	if (!dist_base || !cpu_base)
617 		return;
618 
619 	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
620 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
621 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
622 
623 	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
624 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
625 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
626 
627 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
628 		writel_relaxed(GICD_INT_DEF_PRI_X4,
629 					dist_base + GIC_DIST_PRI + i * 4);
630 
631 	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
632 	gic_cpu_if_up();
633 }
634 
635 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
636 {
637 	int i;
638 
639 	for (i = 0; i < MAX_GIC_NR; i++) {
640 #ifdef CONFIG_GIC_NON_BANKED
641 		/* Skip over unused GICs */
642 		if (!gic_data[i].get_base)
643 			continue;
644 #endif
645 		switch (cmd) {
646 		case CPU_PM_ENTER:
647 			gic_cpu_save(i);
648 			break;
649 		case CPU_PM_ENTER_FAILED:
650 		case CPU_PM_EXIT:
651 			gic_cpu_restore(i);
652 			break;
653 		case CPU_CLUSTER_PM_ENTER:
654 			gic_dist_save(i);
655 			break;
656 		case CPU_CLUSTER_PM_ENTER_FAILED:
657 		case CPU_CLUSTER_PM_EXIT:
658 			gic_dist_restore(i);
659 			break;
660 		}
661 	}
662 
663 	return NOTIFY_OK;
664 }
665 
666 static struct notifier_block gic_notifier_block = {
667 	.notifier_call = gic_notifier,
668 };
669 
670 static void __init gic_pm_init(struct gic_chip_data *gic)
671 {
672 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
673 		sizeof(u32));
674 	BUG_ON(!gic->saved_ppi_enable);
675 
676 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
677 		sizeof(u32));
678 	BUG_ON(!gic->saved_ppi_conf);
679 
680 	if (gic == &gic_data[0])
681 		cpu_pm_register_notifier(&gic_notifier_block);
682 }
683 #else
684 static void __init gic_pm_init(struct gic_chip_data *gic)
685 {
686 }
687 #endif
688 
689 #ifdef CONFIG_SMP
690 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
691 {
692 	int cpu;
693 	unsigned long flags, map = 0;
694 
695 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
696 
697 	/* Convert our logical CPU mask into a physical one. */
698 	for_each_cpu(cpu, mask)
699 		map |= gic_cpu_map[cpu];
700 
701 	/*
702 	 * Ensure that stores to Normal memory are visible to the
703 	 * other CPUs before they observe us issuing the IPI.
704 	 */
705 	dmb(ishst);
706 
707 	/* this always happens on GIC0 */
708 	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
709 
710 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
711 }
712 #endif
713 
714 #ifdef CONFIG_BL_SWITCHER
715 /*
716  * gic_send_sgi - send a SGI directly to given CPU interface number
717  *
718  * cpu_id: the ID for the destination CPU interface
719  * irq: the IPI number to send a SGI for
720  */
721 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
722 {
723 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
724 	cpu_id = 1 << cpu_id;
725 	/* this always happens on GIC0 */
726 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
727 }
728 
729 /*
730  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
731  *
732  * @cpu: the logical CPU number to get the GIC ID for.
733  *
734  * Return the CPU interface ID for the given logical CPU number,
735  * or -1 if the CPU number is too large or the interface ID is
736  * unknown (more than one bit set).
737  */
738 int gic_get_cpu_id(unsigned int cpu)
739 {
740 	unsigned int cpu_bit;
741 
742 	if (cpu >= NR_GIC_CPU_IF)
743 		return -1;
744 	cpu_bit = gic_cpu_map[cpu];
745 	if (cpu_bit & (cpu_bit - 1))
746 		return -1;
747 	return __ffs(cpu_bit);
748 }
749 
750 /*
751  * gic_migrate_target - migrate IRQs to another CPU interface
752  *
753  * @new_cpu_id: the CPU target ID to migrate IRQs to
754  *
755  * Migrate all peripheral interrupts with a target matching the current CPU
756  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
757  * is also updated.  Targets to other CPU interfaces are unchanged.
758  * This must be called with IRQs locally disabled.
759  */
760 void gic_migrate_target(unsigned int new_cpu_id)
761 {
762 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
763 	void __iomem *dist_base;
764 	int i, ror_val, cpu = smp_processor_id();
765 	u32 val, cur_target_mask, active_mask;
766 
767 	if (gic_nr >= MAX_GIC_NR)
768 		BUG();
769 
770 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
771 	if (!dist_base)
772 		return;
773 	gic_irqs = gic_data[gic_nr].gic_irqs;
774 
775 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
776 	cur_target_mask = 0x01010101 << cur_cpu_id;
777 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
778 
779 	raw_spin_lock(&irq_controller_lock);
780 
781 	/* Update the target interface for this logical CPU */
782 	gic_cpu_map[cpu] = 1 << new_cpu_id;
783 
784 	/*
785 	 * Find all the peripheral interrupts targetting the current
786 	 * CPU interface and migrate them to the new CPU interface.
787 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
788 	 */
789 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
790 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
791 		active_mask = val & cur_target_mask;
792 		if (active_mask) {
793 			val &= ~active_mask;
794 			val |= ror32(active_mask, ror_val);
795 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
796 		}
797 	}
798 
799 	raw_spin_unlock(&irq_controller_lock);
800 
801 	/*
802 	 * Now let's migrate and clear any potential SGIs that might be
803 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
804 	 * is a banked register, we can only forward the SGI using
805 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
806 	 * doesn't use that information anyway.
807 	 *
808 	 * For the same reason we do not adjust SGI source information
809 	 * for previously sent SGIs by us to other CPUs either.
810 	 */
811 	for (i = 0; i < 16; i += 4) {
812 		int j;
813 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
814 		if (!val)
815 			continue;
816 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
817 		for (j = i; j < i + 4; j++) {
818 			if (val & 0xff)
819 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
820 						dist_base + GIC_DIST_SOFTINT);
821 			val >>= 8;
822 		}
823 	}
824 }
825 
826 /*
827  * gic_get_sgir_physaddr - get the physical address for the SGI register
828  *
829  * REturn the physical address of the SGI register to be used
830  * by some early assembly code when the kernel is not yet available.
831  */
832 static unsigned long gic_dist_physaddr;
833 
834 unsigned long gic_get_sgir_physaddr(void)
835 {
836 	if (!gic_dist_physaddr)
837 		return 0;
838 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
839 }
840 
841 void __init gic_init_physaddr(struct device_node *node)
842 {
843 	struct resource res;
844 	if (of_address_to_resource(node, 0, &res) == 0) {
845 		gic_dist_physaddr = res.start;
846 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
847 	}
848 }
849 
850 #else
851 #define gic_init_physaddr(node)  do { } while (0)
852 #endif
853 
854 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
855 				irq_hw_number_t hw)
856 {
857 	if (hw < 32) {
858 		irq_set_percpu_devid(irq);
859 		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
860 				    handle_percpu_devid_irq, NULL, NULL);
861 		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
862 	} else {
863 		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
864 				    handle_fasteoi_irq, NULL, NULL);
865 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
866 	}
867 	return 0;
868 }
869 
870 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
871 {
872 }
873 
874 static int gic_irq_domain_xlate(struct irq_domain *d,
875 				struct device_node *controller,
876 				const u32 *intspec, unsigned int intsize,
877 				unsigned long *out_hwirq, unsigned int *out_type)
878 {
879 	unsigned long ret = 0;
880 
881 	if (d->of_node != controller)
882 		return -EINVAL;
883 	if (intsize < 3)
884 		return -EINVAL;
885 
886 	/* Get the interrupt number and add 16 to skip over SGIs */
887 	*out_hwirq = intspec[1] + 16;
888 
889 	/* For SPIs, we need to add 16 more to get the GIC irq ID number */
890 	if (!intspec[0])
891 		*out_hwirq += 16;
892 
893 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
894 
895 	return ret;
896 }
897 
898 #ifdef CONFIG_SMP
899 static int gic_secondary_init(struct notifier_block *nfb, unsigned long action,
900 			      void *hcpu)
901 {
902 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
903 		gic_cpu_init(&gic_data[0]);
904 	return NOTIFY_OK;
905 }
906 
907 /*
908  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
909  * priority because the GIC needs to be up before the ARM generic timers.
910  */
911 static struct notifier_block gic_cpu_notifier = {
912 	.notifier_call = gic_secondary_init,
913 	.priority = 100,
914 };
915 #endif
916 
917 static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
918 				unsigned int nr_irqs, void *arg)
919 {
920 	int i, ret;
921 	irq_hw_number_t hwirq;
922 	unsigned int type = IRQ_TYPE_NONE;
923 	struct of_phandle_args *irq_data = arg;
924 
925 	ret = gic_irq_domain_xlate(domain, irq_data->np, irq_data->args,
926 				   irq_data->args_count, &hwirq, &type);
927 	if (ret)
928 		return ret;
929 
930 	for (i = 0; i < nr_irqs; i++)
931 		gic_irq_domain_map(domain, virq + i, hwirq + i);
932 
933 	return 0;
934 }
935 
936 static const struct irq_domain_ops gic_irq_domain_hierarchy_ops = {
937 	.xlate = gic_irq_domain_xlate,
938 	.alloc = gic_irq_domain_alloc,
939 	.free = irq_domain_free_irqs_top,
940 };
941 
942 static const struct irq_domain_ops gic_irq_domain_ops = {
943 	.map = gic_irq_domain_map,
944 	.unmap = gic_irq_domain_unmap,
945 	.xlate = gic_irq_domain_xlate,
946 };
947 
948 void gic_set_irqchip_flags(unsigned long flags)
949 {
950 	gic_chip.flags |= flags;
951 }
952 
953 void __init gic_init_bases(unsigned int gic_nr, int irq_start,
954 			   void __iomem *dist_base, void __iomem *cpu_base,
955 			   u32 percpu_offset, struct device_node *node)
956 {
957 	irq_hw_number_t hwirq_base;
958 	struct gic_chip_data *gic;
959 	int gic_irqs, irq_base, i;
960 
961 	BUG_ON(gic_nr >= MAX_GIC_NR);
962 
963 	gic = &gic_data[gic_nr];
964 #ifdef CONFIG_GIC_NON_BANKED
965 	if (percpu_offset) { /* Frankein-GIC without banked registers... */
966 		unsigned int cpu;
967 
968 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
969 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
970 		if (WARN_ON(!gic->dist_base.percpu_base ||
971 			    !gic->cpu_base.percpu_base)) {
972 			free_percpu(gic->dist_base.percpu_base);
973 			free_percpu(gic->cpu_base.percpu_base);
974 			return;
975 		}
976 
977 		for_each_possible_cpu(cpu) {
978 			u32 mpidr = cpu_logical_map(cpu);
979 			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
980 			unsigned long offset = percpu_offset * core_id;
981 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) = dist_base + offset;
982 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) = cpu_base + offset;
983 		}
984 
985 		gic_set_base_accessor(gic, gic_get_percpu_base);
986 	} else
987 #endif
988 	{			/* Normal, sane GIC... */
989 		WARN(percpu_offset,
990 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
991 		     percpu_offset);
992 		gic->dist_base.common_base = dist_base;
993 		gic->cpu_base.common_base = cpu_base;
994 		gic_set_base_accessor(gic, gic_get_common_base);
995 	}
996 
997 	/*
998 	 * Initialize the CPU interface map to all CPUs.
999 	 * It will be refined as each CPU probes its ID.
1000 	 */
1001 	for (i = 0; i < NR_GIC_CPU_IF; i++)
1002 		gic_cpu_map[i] = 0xff;
1003 
1004 	/*
1005 	 * Find out how many interrupts are supported.
1006 	 * The GIC only supports up to 1020 interrupt sources.
1007 	 */
1008 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
1009 	gic_irqs = (gic_irqs + 1) * 32;
1010 	if (gic_irqs > 1020)
1011 		gic_irqs = 1020;
1012 	gic->gic_irqs = gic_irqs;
1013 
1014 	if (node) {		/* DT case */
1015 		gic->domain = irq_domain_add_linear(node, gic_irqs,
1016 						    &gic_irq_domain_hierarchy_ops,
1017 						    gic);
1018 	} else {		/* Non-DT case */
1019 		/*
1020 		 * For primary GICs, skip over SGIs.
1021 		 * For secondary GICs, skip over PPIs, too.
1022 		 */
1023 		if (gic_nr == 0 && (irq_start & 31) > 0) {
1024 			hwirq_base = 16;
1025 			if (irq_start != -1)
1026 				irq_start = (irq_start & ~31) + 16;
1027 		} else {
1028 			hwirq_base = 32;
1029 		}
1030 
1031 		gic_irqs -= hwirq_base; /* calculate # of irqs to allocate */
1032 
1033 		irq_base = irq_alloc_descs(irq_start, 16, gic_irqs,
1034 					   numa_node_id());
1035 		if (IS_ERR_VALUE(irq_base)) {
1036 			WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
1037 			     irq_start);
1038 			irq_base = irq_start;
1039 		}
1040 
1041 		gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base,
1042 					hwirq_base, &gic_irq_domain_ops, gic);
1043 	}
1044 
1045 	if (WARN_ON(!gic->domain))
1046 		return;
1047 
1048 	if (gic_nr == 0) {
1049 #ifdef CONFIG_SMP
1050 		set_smp_cross_call(gic_raise_softirq);
1051 		register_cpu_notifier(&gic_cpu_notifier);
1052 #endif
1053 		set_handle_irq(gic_handle_irq);
1054 	}
1055 
1056 	gic_chip.flags |= gic_arch_extn.flags;
1057 	gic_dist_init(gic);
1058 	gic_cpu_init(gic);
1059 	gic_pm_init(gic);
1060 }
1061 
1062 #ifdef CONFIG_OF
1063 static int gic_cnt __initdata;
1064 
1065 static int __init
1066 gic_of_init(struct device_node *node, struct device_node *parent)
1067 {
1068 	void __iomem *cpu_base;
1069 	void __iomem *dist_base;
1070 	u32 percpu_offset;
1071 	int irq;
1072 
1073 	if (WARN_ON(!node))
1074 		return -ENODEV;
1075 
1076 	dist_base = of_iomap(node, 0);
1077 	WARN(!dist_base, "unable to map gic dist registers\n");
1078 
1079 	cpu_base = of_iomap(node, 1);
1080 	WARN(!cpu_base, "unable to map gic cpu registers\n");
1081 
1082 	if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
1083 		percpu_offset = 0;
1084 
1085 	gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
1086 	if (!gic_cnt)
1087 		gic_init_physaddr(node);
1088 
1089 	if (parent) {
1090 		irq = irq_of_parse_and_map(node, 0);
1091 		gic_cascade_irq(gic_cnt, irq);
1092 	}
1093 
1094 	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1095 		gicv2m_of_init(node, gic_data[gic_cnt].domain);
1096 
1097 	gic_cnt++;
1098 	return 0;
1099 }
1100 IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1101 IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
1102 IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
1103 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1104 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1105 IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1106 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1107 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1108 
1109 #endif
1110