xref: /openbmc/linux/drivers/irqchip/irq-gic.c (revision d2999e1b)
1 /*
2  *  linux/arch/arm/common/gic.c
3  *
4  *  Copyright (C) 2002 ARM Limited, All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Interrupt architecture for the GIC:
11  *
12  * o There is one Interrupt Distributor, which receives interrupts
13  *   from system devices and sends them to the Interrupt Controllers.
14  *
15  * o There is one CPU Interface per CPU, which sends interrupts sent
16  *   by the Distributor, and interrupts generated locally, to the
17  *   associated CPU. The base address of the CPU interface is usually
18  *   aliased so that the same address points to different chips depending
19  *   on the CPU it is accessed from.
20  *
21  * Note that IRQs 0-31 are special - they are local to each CPU.
22  * As such, the enable set/clear, pending set/clear and active bit
23  * registers are banked per-cpu for these sources.
24  */
25 #include <linux/init.h>
26 #include <linux/kernel.h>
27 #include <linux/err.h>
28 #include <linux/module.h>
29 #include <linux/list.h>
30 #include <linux/smp.h>
31 #include <linux/cpu.h>
32 #include <linux/cpu_pm.h>
33 #include <linux/cpumask.h>
34 #include <linux/io.h>
35 #include <linux/of.h>
36 #include <linux/of_address.h>
37 #include <linux/of_irq.h>
38 #include <linux/irqdomain.h>
39 #include <linux/interrupt.h>
40 #include <linux/percpu.h>
41 #include <linux/slab.h>
42 #include <linux/irqchip/chained_irq.h>
43 #include <linux/irqchip/arm-gic.h>
44 
45 #include <asm/irq.h>
46 #include <asm/exception.h>
47 #include <asm/smp_plat.h>
48 
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 *__this_cpu_ptr(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_mask_irq(struct irq_data *d)
155 {
156 	u32 mask = 1 << (gic_irq(d) % 32);
157 
158 	raw_spin_lock(&irq_controller_lock);
159 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
160 	if (gic_arch_extn.irq_mask)
161 		gic_arch_extn.irq_mask(d);
162 	raw_spin_unlock(&irq_controller_lock);
163 }
164 
165 static void gic_unmask_irq(struct irq_data *d)
166 {
167 	u32 mask = 1 << (gic_irq(d) % 32);
168 
169 	raw_spin_lock(&irq_controller_lock);
170 	if (gic_arch_extn.irq_unmask)
171 		gic_arch_extn.irq_unmask(d);
172 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_SET + (gic_irq(d) / 32) * 4);
173 	raw_spin_unlock(&irq_controller_lock);
174 }
175 
176 static void gic_eoi_irq(struct irq_data *d)
177 {
178 	if (gic_arch_extn.irq_eoi) {
179 		raw_spin_lock(&irq_controller_lock);
180 		gic_arch_extn.irq_eoi(d);
181 		raw_spin_unlock(&irq_controller_lock);
182 	}
183 
184 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
185 }
186 
187 static int gic_set_type(struct irq_data *d, unsigned int type)
188 {
189 	void __iomem *base = gic_dist_base(d);
190 	unsigned int gicirq = gic_irq(d);
191 	u32 enablemask = 1 << (gicirq % 32);
192 	u32 enableoff = (gicirq / 32) * 4;
193 	u32 confmask = 0x2 << ((gicirq % 16) * 2);
194 	u32 confoff = (gicirq / 16) * 4;
195 	bool enabled = false;
196 	u32 val;
197 
198 	/* Interrupt configuration for SGIs can't be changed */
199 	if (gicirq < 16)
200 		return -EINVAL;
201 
202 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
203 		return -EINVAL;
204 
205 	raw_spin_lock(&irq_controller_lock);
206 
207 	if (gic_arch_extn.irq_set_type)
208 		gic_arch_extn.irq_set_type(d, type);
209 
210 	val = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
211 	if (type == IRQ_TYPE_LEVEL_HIGH)
212 		val &= ~confmask;
213 	else if (type == IRQ_TYPE_EDGE_RISING)
214 		val |= confmask;
215 
216 	/*
217 	 * As recommended by the spec, disable the interrupt before changing
218 	 * the configuration
219 	 */
220 	if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
221 		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
222 		enabled = true;
223 	}
224 
225 	writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
226 
227 	if (enabled)
228 		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
229 
230 	raw_spin_unlock(&irq_controller_lock);
231 
232 	return 0;
233 }
234 
235 static int gic_retrigger(struct irq_data *d)
236 {
237 	if (gic_arch_extn.irq_retrigger)
238 		return gic_arch_extn.irq_retrigger(d);
239 
240 	/* the genirq layer expects 0 if we can't retrigger in hardware */
241 	return 0;
242 }
243 
244 #ifdef CONFIG_SMP
245 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
246 			    bool force)
247 {
248 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
249 	unsigned int cpu, shift = (gic_irq(d) % 4) * 8;
250 	u32 val, mask, bit;
251 
252 	if (!force)
253 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
254 	else
255 		cpu = cpumask_first(mask_val);
256 
257 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
258 		return -EINVAL;
259 
260 	raw_spin_lock(&irq_controller_lock);
261 	mask = 0xff << shift;
262 	bit = gic_cpu_map[cpu] << shift;
263 	val = readl_relaxed(reg) & ~mask;
264 	writel_relaxed(val | bit, reg);
265 	raw_spin_unlock(&irq_controller_lock);
266 
267 	return IRQ_SET_MASK_OK;
268 }
269 #endif
270 
271 #ifdef CONFIG_PM
272 static int gic_set_wake(struct irq_data *d, unsigned int on)
273 {
274 	int ret = -ENXIO;
275 
276 	if (gic_arch_extn.irq_set_wake)
277 		ret = gic_arch_extn.irq_set_wake(d, on);
278 
279 	return ret;
280 }
281 
282 #else
283 #define gic_set_wake	NULL
284 #endif
285 
286 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
287 {
288 	u32 irqstat, irqnr;
289 	struct gic_chip_data *gic = &gic_data[0];
290 	void __iomem *cpu_base = gic_data_cpu_base(gic);
291 
292 	do {
293 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
294 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
295 
296 		if (likely(irqnr > 15 && irqnr < 1021)) {
297 			irqnr = irq_find_mapping(gic->domain, irqnr);
298 			handle_IRQ(irqnr, regs);
299 			continue;
300 		}
301 		if (irqnr < 16) {
302 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
303 #ifdef CONFIG_SMP
304 			handle_IPI(irqnr, regs);
305 #endif
306 			continue;
307 		}
308 		break;
309 	} while (1);
310 }
311 
312 static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
313 {
314 	struct gic_chip_data *chip_data = irq_get_handler_data(irq);
315 	struct irq_chip *chip = irq_get_chip(irq);
316 	unsigned int cascade_irq, gic_irq;
317 	unsigned long status;
318 
319 	chained_irq_enter(chip, desc);
320 
321 	raw_spin_lock(&irq_controller_lock);
322 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
323 	raw_spin_unlock(&irq_controller_lock);
324 
325 	gic_irq = (status & 0x3ff);
326 	if (gic_irq == 1023)
327 		goto out;
328 
329 	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
330 	if (unlikely(gic_irq < 32 || gic_irq > 1020))
331 		handle_bad_irq(cascade_irq, desc);
332 	else
333 		generic_handle_irq(cascade_irq);
334 
335  out:
336 	chained_irq_exit(chip, desc);
337 }
338 
339 static struct irq_chip gic_chip = {
340 	.name			= "GIC",
341 	.irq_mask		= gic_mask_irq,
342 	.irq_unmask		= gic_unmask_irq,
343 	.irq_eoi		= gic_eoi_irq,
344 	.irq_set_type		= gic_set_type,
345 	.irq_retrigger		= gic_retrigger,
346 #ifdef CONFIG_SMP
347 	.irq_set_affinity	= gic_set_affinity,
348 #endif
349 	.irq_set_wake		= gic_set_wake,
350 };
351 
352 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
353 {
354 	if (gic_nr >= MAX_GIC_NR)
355 		BUG();
356 	if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
357 		BUG();
358 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
359 }
360 
361 static u8 gic_get_cpumask(struct gic_chip_data *gic)
362 {
363 	void __iomem *base = gic_data_dist_base(gic);
364 	u32 mask, i;
365 
366 	for (i = mask = 0; i < 32; i += 4) {
367 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
368 		mask |= mask >> 16;
369 		mask |= mask >> 8;
370 		if (mask)
371 			break;
372 	}
373 
374 	if (!mask)
375 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
376 
377 	return mask;
378 }
379 
380 static void __init gic_dist_init(struct gic_chip_data *gic)
381 {
382 	unsigned int i;
383 	u32 cpumask;
384 	unsigned int gic_irqs = gic->gic_irqs;
385 	void __iomem *base = gic_data_dist_base(gic);
386 
387 	writel_relaxed(0, base + GIC_DIST_CTRL);
388 
389 	/*
390 	 * Set all global interrupts to be level triggered, active low.
391 	 */
392 	for (i = 32; i < gic_irqs; i += 16)
393 		writel_relaxed(0, base + GIC_DIST_CONFIG + i * 4 / 16);
394 
395 	/*
396 	 * Set all global interrupts to this CPU only.
397 	 */
398 	cpumask = gic_get_cpumask(gic);
399 	cpumask |= cpumask << 8;
400 	cpumask |= cpumask << 16;
401 	for (i = 32; i < gic_irqs; i += 4)
402 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
403 
404 	/*
405 	 * Set priority on all global interrupts.
406 	 */
407 	for (i = 32; i < gic_irqs; i += 4)
408 		writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
409 
410 	/*
411 	 * Disable all interrupts.  Leave the PPI and SGIs alone
412 	 * as these enables are banked registers.
413 	 */
414 	for (i = 32; i < gic_irqs; i += 32)
415 		writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
416 
417 	writel_relaxed(1, base + GIC_DIST_CTRL);
418 }
419 
420 static void gic_cpu_init(struct gic_chip_data *gic)
421 {
422 	void __iomem *dist_base = gic_data_dist_base(gic);
423 	void __iomem *base = gic_data_cpu_base(gic);
424 	unsigned int cpu_mask, cpu = smp_processor_id();
425 	int i;
426 
427 	/*
428 	 * Get what the GIC says our CPU mask is.
429 	 */
430 	BUG_ON(cpu >= NR_GIC_CPU_IF);
431 	cpu_mask = gic_get_cpumask(gic);
432 	gic_cpu_map[cpu] = cpu_mask;
433 
434 	/*
435 	 * Clear our mask from the other map entries in case they're
436 	 * still undefined.
437 	 */
438 	for (i = 0; i < NR_GIC_CPU_IF; i++)
439 		if (i != cpu)
440 			gic_cpu_map[i] &= ~cpu_mask;
441 
442 	/*
443 	 * Deal with the banked PPI and SGI interrupts - disable all
444 	 * PPI interrupts, ensure all SGI interrupts are enabled.
445 	 */
446 	writel_relaxed(0xffff0000, dist_base + GIC_DIST_ENABLE_CLEAR);
447 	writel_relaxed(0x0000ffff, dist_base + GIC_DIST_ENABLE_SET);
448 
449 	/*
450 	 * Set priority on PPI and SGI interrupts
451 	 */
452 	for (i = 0; i < 32; i += 4)
453 		writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4 / 4);
454 
455 	writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
456 	writel_relaxed(1, base + GIC_CPU_CTRL);
457 }
458 
459 void gic_cpu_if_down(void)
460 {
461 	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
462 	writel_relaxed(0, cpu_base + GIC_CPU_CTRL);
463 }
464 
465 #ifdef CONFIG_CPU_PM
466 /*
467  * Saves the GIC distributor registers during suspend or idle.  Must be called
468  * with interrupts disabled but before powering down the GIC.  After calling
469  * this function, no interrupts will be delivered by the GIC, and another
470  * platform-specific wakeup source must be enabled.
471  */
472 static void gic_dist_save(unsigned int gic_nr)
473 {
474 	unsigned int gic_irqs;
475 	void __iomem *dist_base;
476 	int i;
477 
478 	if (gic_nr >= MAX_GIC_NR)
479 		BUG();
480 
481 	gic_irqs = gic_data[gic_nr].gic_irqs;
482 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
483 
484 	if (!dist_base)
485 		return;
486 
487 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
488 		gic_data[gic_nr].saved_spi_conf[i] =
489 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
490 
491 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
492 		gic_data[gic_nr].saved_spi_target[i] =
493 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
494 
495 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
496 		gic_data[gic_nr].saved_spi_enable[i] =
497 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
498 }
499 
500 /*
501  * Restores the GIC distributor registers during resume or when coming out of
502  * idle.  Must be called before enabling interrupts.  If a level interrupt
503  * that occured while the GIC was suspended is still present, it will be
504  * handled normally, but any edge interrupts that occured will not be seen by
505  * the GIC and need to be handled by the platform-specific wakeup source.
506  */
507 static void gic_dist_restore(unsigned int gic_nr)
508 {
509 	unsigned int gic_irqs;
510 	unsigned int i;
511 	void __iomem *dist_base;
512 
513 	if (gic_nr >= MAX_GIC_NR)
514 		BUG();
515 
516 	gic_irqs = gic_data[gic_nr].gic_irqs;
517 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
518 
519 	if (!dist_base)
520 		return;
521 
522 	writel_relaxed(0, dist_base + GIC_DIST_CTRL);
523 
524 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
525 		writel_relaxed(gic_data[gic_nr].saved_spi_conf[i],
526 			dist_base + GIC_DIST_CONFIG + i * 4);
527 
528 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
529 		writel_relaxed(0xa0a0a0a0,
530 			dist_base + GIC_DIST_PRI + i * 4);
531 
532 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
533 		writel_relaxed(gic_data[gic_nr].saved_spi_target[i],
534 			dist_base + GIC_DIST_TARGET + i * 4);
535 
536 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
537 		writel_relaxed(gic_data[gic_nr].saved_spi_enable[i],
538 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
539 
540 	writel_relaxed(1, dist_base + GIC_DIST_CTRL);
541 }
542 
543 static void gic_cpu_save(unsigned int gic_nr)
544 {
545 	int i;
546 	u32 *ptr;
547 	void __iomem *dist_base;
548 	void __iomem *cpu_base;
549 
550 	if (gic_nr >= MAX_GIC_NR)
551 		BUG();
552 
553 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
554 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
555 
556 	if (!dist_base || !cpu_base)
557 		return;
558 
559 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
560 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
561 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
562 
563 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
564 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
565 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
566 
567 }
568 
569 static void gic_cpu_restore(unsigned int gic_nr)
570 {
571 	int i;
572 	u32 *ptr;
573 	void __iomem *dist_base;
574 	void __iomem *cpu_base;
575 
576 	if (gic_nr >= MAX_GIC_NR)
577 		BUG();
578 
579 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
580 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
581 
582 	if (!dist_base || !cpu_base)
583 		return;
584 
585 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
586 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
587 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
588 
589 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
590 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
591 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
592 
593 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
594 		writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4);
595 
596 	writel_relaxed(0xf0, cpu_base + GIC_CPU_PRIMASK);
597 	writel_relaxed(1, cpu_base + GIC_CPU_CTRL);
598 }
599 
600 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
601 {
602 	int i;
603 
604 	for (i = 0; i < MAX_GIC_NR; i++) {
605 #ifdef CONFIG_GIC_NON_BANKED
606 		/* Skip over unused GICs */
607 		if (!gic_data[i].get_base)
608 			continue;
609 #endif
610 		switch (cmd) {
611 		case CPU_PM_ENTER:
612 			gic_cpu_save(i);
613 			break;
614 		case CPU_PM_ENTER_FAILED:
615 		case CPU_PM_EXIT:
616 			gic_cpu_restore(i);
617 			break;
618 		case CPU_CLUSTER_PM_ENTER:
619 			gic_dist_save(i);
620 			break;
621 		case CPU_CLUSTER_PM_ENTER_FAILED:
622 		case CPU_CLUSTER_PM_EXIT:
623 			gic_dist_restore(i);
624 			break;
625 		}
626 	}
627 
628 	return NOTIFY_OK;
629 }
630 
631 static struct notifier_block gic_notifier_block = {
632 	.notifier_call = gic_notifier,
633 };
634 
635 static void __init gic_pm_init(struct gic_chip_data *gic)
636 {
637 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
638 		sizeof(u32));
639 	BUG_ON(!gic->saved_ppi_enable);
640 
641 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
642 		sizeof(u32));
643 	BUG_ON(!gic->saved_ppi_conf);
644 
645 	if (gic == &gic_data[0])
646 		cpu_pm_register_notifier(&gic_notifier_block);
647 }
648 #else
649 static void __init gic_pm_init(struct gic_chip_data *gic)
650 {
651 }
652 #endif
653 
654 #ifdef CONFIG_SMP
655 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
656 {
657 	int cpu;
658 	unsigned long flags, map = 0;
659 
660 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
661 
662 	/* Convert our logical CPU mask into a physical one. */
663 	for_each_cpu(cpu, mask)
664 		map |= gic_cpu_map[cpu];
665 
666 	/*
667 	 * Ensure that stores to Normal memory are visible to the
668 	 * other CPUs before they observe us issuing the IPI.
669 	 */
670 	dmb(ishst);
671 
672 	/* this always happens on GIC0 */
673 	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
674 
675 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
676 }
677 #endif
678 
679 #ifdef CONFIG_BL_SWITCHER
680 /*
681  * gic_send_sgi - send a SGI directly to given CPU interface number
682  *
683  * cpu_id: the ID for the destination CPU interface
684  * irq: the IPI number to send a SGI for
685  */
686 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
687 {
688 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
689 	cpu_id = 1 << cpu_id;
690 	/* this always happens on GIC0 */
691 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
692 }
693 
694 /*
695  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
696  *
697  * @cpu: the logical CPU number to get the GIC ID for.
698  *
699  * Return the CPU interface ID for the given logical CPU number,
700  * or -1 if the CPU number is too large or the interface ID is
701  * unknown (more than one bit set).
702  */
703 int gic_get_cpu_id(unsigned int cpu)
704 {
705 	unsigned int cpu_bit;
706 
707 	if (cpu >= NR_GIC_CPU_IF)
708 		return -1;
709 	cpu_bit = gic_cpu_map[cpu];
710 	if (cpu_bit & (cpu_bit - 1))
711 		return -1;
712 	return __ffs(cpu_bit);
713 }
714 
715 /*
716  * gic_migrate_target - migrate IRQs to another CPU interface
717  *
718  * @new_cpu_id: the CPU target ID to migrate IRQs to
719  *
720  * Migrate all peripheral interrupts with a target matching the current CPU
721  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
722  * is also updated.  Targets to other CPU interfaces are unchanged.
723  * This must be called with IRQs locally disabled.
724  */
725 void gic_migrate_target(unsigned int new_cpu_id)
726 {
727 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
728 	void __iomem *dist_base;
729 	int i, ror_val, cpu = smp_processor_id();
730 	u32 val, cur_target_mask, active_mask;
731 
732 	if (gic_nr >= MAX_GIC_NR)
733 		BUG();
734 
735 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
736 	if (!dist_base)
737 		return;
738 	gic_irqs = gic_data[gic_nr].gic_irqs;
739 
740 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
741 	cur_target_mask = 0x01010101 << cur_cpu_id;
742 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
743 
744 	raw_spin_lock(&irq_controller_lock);
745 
746 	/* Update the target interface for this logical CPU */
747 	gic_cpu_map[cpu] = 1 << new_cpu_id;
748 
749 	/*
750 	 * Find all the peripheral interrupts targetting the current
751 	 * CPU interface and migrate them to the new CPU interface.
752 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
753 	 */
754 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
755 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
756 		active_mask = val & cur_target_mask;
757 		if (active_mask) {
758 			val &= ~active_mask;
759 			val |= ror32(active_mask, ror_val);
760 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
761 		}
762 	}
763 
764 	raw_spin_unlock(&irq_controller_lock);
765 
766 	/*
767 	 * Now let's migrate and clear any potential SGIs that might be
768 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
769 	 * is a banked register, we can only forward the SGI using
770 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
771 	 * doesn't use that information anyway.
772 	 *
773 	 * For the same reason we do not adjust SGI source information
774 	 * for previously sent SGIs by us to other CPUs either.
775 	 */
776 	for (i = 0; i < 16; i += 4) {
777 		int j;
778 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
779 		if (!val)
780 			continue;
781 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
782 		for (j = i; j < i + 4; j++) {
783 			if (val & 0xff)
784 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
785 						dist_base + GIC_DIST_SOFTINT);
786 			val >>= 8;
787 		}
788 	}
789 }
790 
791 /*
792  * gic_get_sgir_physaddr - get the physical address for the SGI register
793  *
794  * REturn the physical address of the SGI register to be used
795  * by some early assembly code when the kernel is not yet available.
796  */
797 static unsigned long gic_dist_physaddr;
798 
799 unsigned long gic_get_sgir_physaddr(void)
800 {
801 	if (!gic_dist_physaddr)
802 		return 0;
803 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
804 }
805 
806 void __init gic_init_physaddr(struct device_node *node)
807 {
808 	struct resource res;
809 	if (of_address_to_resource(node, 0, &res) == 0) {
810 		gic_dist_physaddr = res.start;
811 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
812 	}
813 }
814 
815 #else
816 #define gic_init_physaddr(node)  do { } while (0)
817 #endif
818 
819 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
820 				irq_hw_number_t hw)
821 {
822 	if (hw < 32) {
823 		irq_set_percpu_devid(irq);
824 		irq_set_chip_and_handler(irq, &gic_chip,
825 					 handle_percpu_devid_irq);
826 		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
827 	} else {
828 		irq_set_chip_and_handler(irq, &gic_chip,
829 					 handle_fasteoi_irq);
830 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
831 
832 		gic_routable_irq_domain_ops->map(d, irq, hw);
833 	}
834 	irq_set_chip_data(irq, d->host_data);
835 	return 0;
836 }
837 
838 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
839 {
840 	gic_routable_irq_domain_ops->unmap(d, irq);
841 }
842 
843 static int gic_irq_domain_xlate(struct irq_domain *d,
844 				struct device_node *controller,
845 				const u32 *intspec, unsigned int intsize,
846 				unsigned long *out_hwirq, unsigned int *out_type)
847 {
848 	unsigned long ret = 0;
849 
850 	if (d->of_node != controller)
851 		return -EINVAL;
852 	if (intsize < 3)
853 		return -EINVAL;
854 
855 	/* Get the interrupt number and add 16 to skip over SGIs */
856 	*out_hwirq = intspec[1] + 16;
857 
858 	/* For SPIs, we need to add 16 more to get the GIC irq ID number */
859 	if (!intspec[0]) {
860 		ret = gic_routable_irq_domain_ops->xlate(d, controller,
861 							 intspec,
862 							 intsize,
863 							 out_hwirq,
864 							 out_type);
865 
866 		if (IS_ERR_VALUE(ret))
867 			return ret;
868 	}
869 
870 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
871 
872 	return ret;
873 }
874 
875 #ifdef CONFIG_SMP
876 static int gic_secondary_init(struct notifier_block *nfb, unsigned long action,
877 			      void *hcpu)
878 {
879 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
880 		gic_cpu_init(&gic_data[0]);
881 	return NOTIFY_OK;
882 }
883 
884 /*
885  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
886  * priority because the GIC needs to be up before the ARM generic timers.
887  */
888 static struct notifier_block gic_cpu_notifier = {
889 	.notifier_call = gic_secondary_init,
890 	.priority = 100,
891 };
892 #endif
893 
894 static const struct irq_domain_ops gic_irq_domain_ops = {
895 	.map = gic_irq_domain_map,
896 	.unmap = gic_irq_domain_unmap,
897 	.xlate = gic_irq_domain_xlate,
898 };
899 
900 /* Default functions for routable irq domain */
901 static int gic_routable_irq_domain_map(struct irq_domain *d, unsigned int irq,
902 			      irq_hw_number_t hw)
903 {
904 	return 0;
905 }
906 
907 static void gic_routable_irq_domain_unmap(struct irq_domain *d,
908 					  unsigned int irq)
909 {
910 }
911 
912 static int gic_routable_irq_domain_xlate(struct irq_domain *d,
913 				struct device_node *controller,
914 				const u32 *intspec, unsigned int intsize,
915 				unsigned long *out_hwirq,
916 				unsigned int *out_type)
917 {
918 	*out_hwirq += 16;
919 	return 0;
920 }
921 
922 const struct irq_domain_ops gic_default_routable_irq_domain_ops = {
923 	.map = gic_routable_irq_domain_map,
924 	.unmap = gic_routable_irq_domain_unmap,
925 	.xlate = gic_routable_irq_domain_xlate,
926 };
927 
928 const struct irq_domain_ops *gic_routable_irq_domain_ops =
929 					&gic_default_routable_irq_domain_ops;
930 
931 void __init gic_init_bases(unsigned int gic_nr, int irq_start,
932 			   void __iomem *dist_base, void __iomem *cpu_base,
933 			   u32 percpu_offset, struct device_node *node)
934 {
935 	irq_hw_number_t hwirq_base;
936 	struct gic_chip_data *gic;
937 	int gic_irqs, irq_base, i;
938 	int nr_routable_irqs;
939 
940 	BUG_ON(gic_nr >= MAX_GIC_NR);
941 
942 	gic = &gic_data[gic_nr];
943 #ifdef CONFIG_GIC_NON_BANKED
944 	if (percpu_offset) { /* Frankein-GIC without banked registers... */
945 		unsigned int cpu;
946 
947 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
948 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
949 		if (WARN_ON(!gic->dist_base.percpu_base ||
950 			    !gic->cpu_base.percpu_base)) {
951 			free_percpu(gic->dist_base.percpu_base);
952 			free_percpu(gic->cpu_base.percpu_base);
953 			return;
954 		}
955 
956 		for_each_possible_cpu(cpu) {
957 			unsigned long offset = percpu_offset * cpu_logical_map(cpu);
958 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) = dist_base + offset;
959 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) = cpu_base + offset;
960 		}
961 
962 		gic_set_base_accessor(gic, gic_get_percpu_base);
963 	} else
964 #endif
965 	{			/* Normal, sane GIC... */
966 		WARN(percpu_offset,
967 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
968 		     percpu_offset);
969 		gic->dist_base.common_base = dist_base;
970 		gic->cpu_base.common_base = cpu_base;
971 		gic_set_base_accessor(gic, gic_get_common_base);
972 	}
973 
974 	/*
975 	 * Initialize the CPU interface map to all CPUs.
976 	 * It will be refined as each CPU probes its ID.
977 	 */
978 	for (i = 0; i < NR_GIC_CPU_IF; i++)
979 		gic_cpu_map[i] = 0xff;
980 
981 	/*
982 	 * For primary GICs, skip over SGIs.
983 	 * For secondary GICs, skip over PPIs, too.
984 	 */
985 	if (gic_nr == 0 && (irq_start & 31) > 0) {
986 		hwirq_base = 16;
987 		if (irq_start != -1)
988 			irq_start = (irq_start & ~31) + 16;
989 	} else {
990 		hwirq_base = 32;
991 	}
992 
993 	/*
994 	 * Find out how many interrupts are supported.
995 	 * The GIC only supports up to 1020 interrupt sources.
996 	 */
997 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
998 	gic_irqs = (gic_irqs + 1) * 32;
999 	if (gic_irqs > 1020)
1000 		gic_irqs = 1020;
1001 	gic->gic_irqs = gic_irqs;
1002 
1003 	gic_irqs -= hwirq_base; /* calculate # of irqs to allocate */
1004 
1005 	if (of_property_read_u32(node, "arm,routable-irqs",
1006 				 &nr_routable_irqs)) {
1007 		irq_base = irq_alloc_descs(irq_start, 16, gic_irqs,
1008 					   numa_node_id());
1009 		if (IS_ERR_VALUE(irq_base)) {
1010 			WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
1011 			     irq_start);
1012 			irq_base = irq_start;
1013 		}
1014 
1015 		gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base,
1016 					hwirq_base, &gic_irq_domain_ops, gic);
1017 	} else {
1018 		gic->domain = irq_domain_add_linear(node, nr_routable_irqs,
1019 						    &gic_irq_domain_ops,
1020 						    gic);
1021 	}
1022 
1023 	if (WARN_ON(!gic->domain))
1024 		return;
1025 
1026 	if (gic_nr == 0) {
1027 #ifdef CONFIG_SMP
1028 		set_smp_cross_call(gic_raise_softirq);
1029 		register_cpu_notifier(&gic_cpu_notifier);
1030 #endif
1031 		set_handle_irq(gic_handle_irq);
1032 	}
1033 
1034 	gic_chip.flags |= gic_arch_extn.flags;
1035 	gic_dist_init(gic);
1036 	gic_cpu_init(gic);
1037 	gic_pm_init(gic);
1038 }
1039 
1040 #ifdef CONFIG_OF
1041 static int gic_cnt __initdata;
1042 
1043 static int __init
1044 gic_of_init(struct device_node *node, struct device_node *parent)
1045 {
1046 	void __iomem *cpu_base;
1047 	void __iomem *dist_base;
1048 	u32 percpu_offset;
1049 	int irq;
1050 
1051 	if (WARN_ON(!node))
1052 		return -ENODEV;
1053 
1054 	dist_base = of_iomap(node, 0);
1055 	WARN(!dist_base, "unable to map gic dist registers\n");
1056 
1057 	cpu_base = of_iomap(node, 1);
1058 	WARN(!cpu_base, "unable to map gic cpu registers\n");
1059 
1060 	if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
1061 		percpu_offset = 0;
1062 
1063 	gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
1064 	if (!gic_cnt)
1065 		gic_init_physaddr(node);
1066 
1067 	if (parent) {
1068 		irq = irq_of_parse_and_map(node, 0);
1069 		gic_cascade_irq(gic_cnt, irq);
1070 	}
1071 	gic_cnt++;
1072 	return 0;
1073 }
1074 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1075 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1076 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1077 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1078 
1079 #endif
1080