xref: /openbmc/linux/drivers/irqchip/irq-gic.c (revision d2168146)
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/cputype.h>
46 #include <asm/irq.h>
47 #include <asm/exception.h>
48 #include <asm/smp_plat.h>
49 
50 #include "irqchip.h"
51 
52 union gic_base {
53 	void __iomem *common_base;
54 	void __percpu * __iomem *percpu_base;
55 };
56 
57 struct gic_chip_data {
58 	union gic_base dist_base;
59 	union gic_base cpu_base;
60 #ifdef CONFIG_CPU_PM
61 	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
62 	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
63 	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
64 	u32 __percpu *saved_ppi_enable;
65 	u32 __percpu *saved_ppi_conf;
66 #endif
67 	struct irq_domain *domain;
68 	unsigned int gic_irqs;
69 #ifdef CONFIG_GIC_NON_BANKED
70 	void __iomem *(*get_base)(union gic_base *);
71 #endif
72 };
73 
74 static DEFINE_RAW_SPINLOCK(irq_controller_lock);
75 
76 /*
77  * The GIC mapping of CPU interfaces does not necessarily match
78  * the logical CPU numbering.  Let's use a mapping as returned
79  * by the GIC itself.
80  */
81 #define NR_GIC_CPU_IF 8
82 static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
83 
84 /*
85  * Supported arch specific GIC irq extension.
86  * Default make them NULL.
87  */
88 struct irq_chip gic_arch_extn = {
89 	.irq_eoi	= NULL,
90 	.irq_mask	= NULL,
91 	.irq_unmask	= NULL,
92 	.irq_retrigger	= NULL,
93 	.irq_set_type	= NULL,
94 	.irq_set_wake	= NULL,
95 };
96 
97 #ifndef MAX_GIC_NR
98 #define MAX_GIC_NR	1
99 #endif
100 
101 static struct gic_chip_data gic_data[MAX_GIC_NR] __read_mostly;
102 
103 #ifdef CONFIG_GIC_NON_BANKED
104 static void __iomem *gic_get_percpu_base(union gic_base *base)
105 {
106 	return *__this_cpu_ptr(base->percpu_base);
107 }
108 
109 static void __iomem *gic_get_common_base(union gic_base *base)
110 {
111 	return base->common_base;
112 }
113 
114 static inline void __iomem *gic_data_dist_base(struct gic_chip_data *data)
115 {
116 	return data->get_base(&data->dist_base);
117 }
118 
119 static inline void __iomem *gic_data_cpu_base(struct gic_chip_data *data)
120 {
121 	return data->get_base(&data->cpu_base);
122 }
123 
124 static inline void gic_set_base_accessor(struct gic_chip_data *data,
125 					 void __iomem *(*f)(union gic_base *))
126 {
127 	data->get_base = f;
128 }
129 #else
130 #define gic_data_dist_base(d)	((d)->dist_base.common_base)
131 #define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
132 #define gic_set_base_accessor(d, f)
133 #endif
134 
135 static inline void __iomem *gic_dist_base(struct irq_data *d)
136 {
137 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
138 	return gic_data_dist_base(gic_data);
139 }
140 
141 static inline void __iomem *gic_cpu_base(struct irq_data *d)
142 {
143 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
144 	return gic_data_cpu_base(gic_data);
145 }
146 
147 static inline unsigned int gic_irq(struct irq_data *d)
148 {
149 	return d->hwirq;
150 }
151 
152 /*
153  * Routines to acknowledge, disable and enable interrupts
154  */
155 static void gic_mask_irq(struct irq_data *d)
156 {
157 	u32 mask = 1 << (gic_irq(d) % 32);
158 
159 	raw_spin_lock(&irq_controller_lock);
160 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
161 	if (gic_arch_extn.irq_mask)
162 		gic_arch_extn.irq_mask(d);
163 	raw_spin_unlock(&irq_controller_lock);
164 }
165 
166 static void gic_unmask_irq(struct irq_data *d)
167 {
168 	u32 mask = 1 << (gic_irq(d) % 32);
169 
170 	raw_spin_lock(&irq_controller_lock);
171 	if (gic_arch_extn.irq_unmask)
172 		gic_arch_extn.irq_unmask(d);
173 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_SET + (gic_irq(d) / 32) * 4);
174 	raw_spin_unlock(&irq_controller_lock);
175 }
176 
177 static void gic_eoi_irq(struct irq_data *d)
178 {
179 	if (gic_arch_extn.irq_eoi) {
180 		raw_spin_lock(&irq_controller_lock);
181 		gic_arch_extn.irq_eoi(d);
182 		raw_spin_unlock(&irq_controller_lock);
183 	}
184 
185 	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
186 }
187 
188 static int gic_set_type(struct irq_data *d, unsigned int type)
189 {
190 	void __iomem *base = gic_dist_base(d);
191 	unsigned int gicirq = gic_irq(d);
192 	u32 enablemask = 1 << (gicirq % 32);
193 	u32 enableoff = (gicirq / 32) * 4;
194 	u32 confmask = 0x2 << ((gicirq % 16) * 2);
195 	u32 confoff = (gicirq / 16) * 4;
196 	bool enabled = false;
197 	u32 val;
198 
199 	/* Interrupt configuration for SGIs can't be changed */
200 	if (gicirq < 16)
201 		return -EINVAL;
202 
203 	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
204 		return -EINVAL;
205 
206 	raw_spin_lock(&irq_controller_lock);
207 
208 	if (gic_arch_extn.irq_set_type)
209 		gic_arch_extn.irq_set_type(d, type);
210 
211 	val = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
212 	if (type == IRQ_TYPE_LEVEL_HIGH)
213 		val &= ~confmask;
214 	else if (type == IRQ_TYPE_EDGE_RISING)
215 		val |= confmask;
216 
217 	/*
218 	 * As recommended by the spec, disable the interrupt before changing
219 	 * the configuration
220 	 */
221 	if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
222 		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
223 		enabled = true;
224 	}
225 
226 	writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
227 
228 	if (enabled)
229 		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
230 
231 	raw_spin_unlock(&irq_controller_lock);
232 
233 	return 0;
234 }
235 
236 static int gic_retrigger(struct irq_data *d)
237 {
238 	if (gic_arch_extn.irq_retrigger)
239 		return gic_arch_extn.irq_retrigger(d);
240 
241 	/* the genirq layer expects 0 if we can't retrigger in hardware */
242 	return 0;
243 }
244 
245 #ifdef CONFIG_SMP
246 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
247 			    bool force)
248 {
249 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
250 	unsigned int cpu, shift = (gic_irq(d) % 4) * 8;
251 	u32 val, mask, bit;
252 
253 	if (!force)
254 		cpu = cpumask_any_and(mask_val, cpu_online_mask);
255 	else
256 		cpu = cpumask_first(mask_val);
257 
258 	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
259 		return -EINVAL;
260 
261 	raw_spin_lock(&irq_controller_lock);
262 	mask = 0xff << shift;
263 	bit = gic_cpu_map[cpu] << shift;
264 	val = readl_relaxed(reg) & ~mask;
265 	writel_relaxed(val | bit, reg);
266 	raw_spin_unlock(&irq_controller_lock);
267 
268 	return IRQ_SET_MASK_OK;
269 }
270 #endif
271 
272 #ifdef CONFIG_PM
273 static int gic_set_wake(struct irq_data *d, unsigned int on)
274 {
275 	int ret = -ENXIO;
276 
277 	if (gic_arch_extn.irq_set_wake)
278 		ret = gic_arch_extn.irq_set_wake(d, on);
279 
280 	return ret;
281 }
282 
283 #else
284 #define gic_set_wake	NULL
285 #endif
286 
287 static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
288 {
289 	u32 irqstat, irqnr;
290 	struct gic_chip_data *gic = &gic_data[0];
291 	void __iomem *cpu_base = gic_data_cpu_base(gic);
292 
293 	do {
294 		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
295 		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
296 
297 		if (likely(irqnr > 15 && irqnr < 1021)) {
298 			irqnr = irq_find_mapping(gic->domain, irqnr);
299 			handle_IRQ(irqnr, regs);
300 			continue;
301 		}
302 		if (irqnr < 16) {
303 			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
304 #ifdef CONFIG_SMP
305 			handle_IPI(irqnr, regs);
306 #endif
307 			continue;
308 		}
309 		break;
310 	} while (1);
311 }
312 
313 static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
314 {
315 	struct gic_chip_data *chip_data = irq_get_handler_data(irq);
316 	struct irq_chip *chip = irq_get_chip(irq);
317 	unsigned int cascade_irq, gic_irq;
318 	unsigned long status;
319 
320 	chained_irq_enter(chip, desc);
321 
322 	raw_spin_lock(&irq_controller_lock);
323 	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
324 	raw_spin_unlock(&irq_controller_lock);
325 
326 	gic_irq = (status & 0x3ff);
327 	if (gic_irq == 1023)
328 		goto out;
329 
330 	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
331 	if (unlikely(gic_irq < 32 || gic_irq > 1020))
332 		handle_bad_irq(cascade_irq, desc);
333 	else
334 		generic_handle_irq(cascade_irq);
335 
336  out:
337 	chained_irq_exit(chip, desc);
338 }
339 
340 static struct irq_chip gic_chip = {
341 	.name			= "GIC",
342 	.irq_mask		= gic_mask_irq,
343 	.irq_unmask		= gic_unmask_irq,
344 	.irq_eoi		= gic_eoi_irq,
345 	.irq_set_type		= gic_set_type,
346 	.irq_retrigger		= gic_retrigger,
347 #ifdef CONFIG_SMP
348 	.irq_set_affinity	= gic_set_affinity,
349 #endif
350 	.irq_set_wake		= gic_set_wake,
351 };
352 
353 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
354 {
355 	if (gic_nr >= MAX_GIC_NR)
356 		BUG();
357 	if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
358 		BUG();
359 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
360 }
361 
362 static u8 gic_get_cpumask(struct gic_chip_data *gic)
363 {
364 	void __iomem *base = gic_data_dist_base(gic);
365 	u32 mask, i;
366 
367 	for (i = mask = 0; i < 32; i += 4) {
368 		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
369 		mask |= mask >> 16;
370 		mask |= mask >> 8;
371 		if (mask)
372 			break;
373 	}
374 
375 	if (!mask)
376 		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
377 
378 	return mask;
379 }
380 
381 static void __init gic_dist_init(struct gic_chip_data *gic)
382 {
383 	unsigned int i;
384 	u32 cpumask;
385 	unsigned int gic_irqs = gic->gic_irqs;
386 	void __iomem *base = gic_data_dist_base(gic);
387 
388 	writel_relaxed(0, base + GIC_DIST_CTRL);
389 
390 	/*
391 	 * Set all global interrupts to be level triggered, active low.
392 	 */
393 	for (i = 32; i < gic_irqs; i += 16)
394 		writel_relaxed(0, base + GIC_DIST_CONFIG + i * 4 / 16);
395 
396 	/*
397 	 * Set all global interrupts to this CPU only.
398 	 */
399 	cpumask = gic_get_cpumask(gic);
400 	cpumask |= cpumask << 8;
401 	cpumask |= cpumask << 16;
402 	for (i = 32; i < gic_irqs; i += 4)
403 		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
404 
405 	/*
406 	 * Set priority on all global interrupts.
407 	 */
408 	for (i = 32; i < gic_irqs; i += 4)
409 		writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4);
410 
411 	/*
412 	 * Disable all interrupts.  Leave the PPI and SGIs alone
413 	 * as these enables are banked registers.
414 	 */
415 	for (i = 32; i < gic_irqs; i += 32)
416 		writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
417 
418 	writel_relaxed(1, base + GIC_DIST_CTRL);
419 }
420 
421 static void gic_cpu_init(struct gic_chip_data *gic)
422 {
423 	void __iomem *dist_base = gic_data_dist_base(gic);
424 	void __iomem *base = gic_data_cpu_base(gic);
425 	unsigned int cpu_mask, cpu = smp_processor_id();
426 	int i;
427 
428 	/*
429 	 * Get what the GIC says our CPU mask is.
430 	 */
431 	BUG_ON(cpu >= NR_GIC_CPU_IF);
432 	cpu_mask = gic_get_cpumask(gic);
433 	gic_cpu_map[cpu] = cpu_mask;
434 
435 	/*
436 	 * Clear our mask from the other map entries in case they're
437 	 * still undefined.
438 	 */
439 	for (i = 0; i < NR_GIC_CPU_IF; i++)
440 		if (i != cpu)
441 			gic_cpu_map[i] &= ~cpu_mask;
442 
443 	/*
444 	 * Deal with the banked PPI and SGI interrupts - disable all
445 	 * PPI interrupts, ensure all SGI interrupts are enabled.
446 	 */
447 	writel_relaxed(0xffff0000, dist_base + GIC_DIST_ENABLE_CLEAR);
448 	writel_relaxed(0x0000ffff, dist_base + GIC_DIST_ENABLE_SET);
449 
450 	/*
451 	 * Set priority on PPI and SGI interrupts
452 	 */
453 	for (i = 0; i < 32; i += 4)
454 		writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4 / 4);
455 
456 	writel_relaxed(0xf0, base + GIC_CPU_PRIMASK);
457 	writel_relaxed(1, base + GIC_CPU_CTRL);
458 }
459 
460 void gic_cpu_if_down(void)
461 {
462 	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
463 	writel_relaxed(0, cpu_base + GIC_CPU_CTRL);
464 }
465 
466 #ifdef CONFIG_CPU_PM
467 /*
468  * Saves the GIC distributor registers during suspend or idle.  Must be called
469  * with interrupts disabled but before powering down the GIC.  After calling
470  * this function, no interrupts will be delivered by the GIC, and another
471  * platform-specific wakeup source must be enabled.
472  */
473 static void gic_dist_save(unsigned int gic_nr)
474 {
475 	unsigned int gic_irqs;
476 	void __iomem *dist_base;
477 	int i;
478 
479 	if (gic_nr >= MAX_GIC_NR)
480 		BUG();
481 
482 	gic_irqs = gic_data[gic_nr].gic_irqs;
483 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
484 
485 	if (!dist_base)
486 		return;
487 
488 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
489 		gic_data[gic_nr].saved_spi_conf[i] =
490 			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
491 
492 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
493 		gic_data[gic_nr].saved_spi_target[i] =
494 			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
495 
496 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
497 		gic_data[gic_nr].saved_spi_enable[i] =
498 			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
499 }
500 
501 /*
502  * Restores the GIC distributor registers during resume or when coming out of
503  * idle.  Must be called before enabling interrupts.  If a level interrupt
504  * that occured while the GIC was suspended is still present, it will be
505  * handled normally, but any edge interrupts that occured will not be seen by
506  * the GIC and need to be handled by the platform-specific wakeup source.
507  */
508 static void gic_dist_restore(unsigned int gic_nr)
509 {
510 	unsigned int gic_irqs;
511 	unsigned int i;
512 	void __iomem *dist_base;
513 
514 	if (gic_nr >= MAX_GIC_NR)
515 		BUG();
516 
517 	gic_irqs = gic_data[gic_nr].gic_irqs;
518 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
519 
520 	if (!dist_base)
521 		return;
522 
523 	writel_relaxed(0, dist_base + GIC_DIST_CTRL);
524 
525 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
526 		writel_relaxed(gic_data[gic_nr].saved_spi_conf[i],
527 			dist_base + GIC_DIST_CONFIG + i * 4);
528 
529 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
530 		writel_relaxed(0xa0a0a0a0,
531 			dist_base + GIC_DIST_PRI + i * 4);
532 
533 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
534 		writel_relaxed(gic_data[gic_nr].saved_spi_target[i],
535 			dist_base + GIC_DIST_TARGET + i * 4);
536 
537 	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
538 		writel_relaxed(gic_data[gic_nr].saved_spi_enable[i],
539 			dist_base + GIC_DIST_ENABLE_SET + i * 4);
540 
541 	writel_relaxed(1, dist_base + GIC_DIST_CTRL);
542 }
543 
544 static void gic_cpu_save(unsigned int gic_nr)
545 {
546 	int i;
547 	u32 *ptr;
548 	void __iomem *dist_base;
549 	void __iomem *cpu_base;
550 
551 	if (gic_nr >= MAX_GIC_NR)
552 		BUG();
553 
554 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
555 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
556 
557 	if (!dist_base || !cpu_base)
558 		return;
559 
560 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
561 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
562 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
563 
564 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
565 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
566 		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
567 
568 }
569 
570 static void gic_cpu_restore(unsigned int gic_nr)
571 {
572 	int i;
573 	u32 *ptr;
574 	void __iomem *dist_base;
575 	void __iomem *cpu_base;
576 
577 	if (gic_nr >= MAX_GIC_NR)
578 		BUG();
579 
580 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
581 	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
582 
583 	if (!dist_base || !cpu_base)
584 		return;
585 
586 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
587 	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
588 		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
589 
590 	ptr = __this_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
591 	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
592 		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
593 
594 	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
595 		writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4);
596 
597 	writel_relaxed(0xf0, cpu_base + GIC_CPU_PRIMASK);
598 	writel_relaxed(1, cpu_base + GIC_CPU_CTRL);
599 }
600 
601 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
602 {
603 	int i;
604 
605 	for (i = 0; i < MAX_GIC_NR; i++) {
606 #ifdef CONFIG_GIC_NON_BANKED
607 		/* Skip over unused GICs */
608 		if (!gic_data[i].get_base)
609 			continue;
610 #endif
611 		switch (cmd) {
612 		case CPU_PM_ENTER:
613 			gic_cpu_save(i);
614 			break;
615 		case CPU_PM_ENTER_FAILED:
616 		case CPU_PM_EXIT:
617 			gic_cpu_restore(i);
618 			break;
619 		case CPU_CLUSTER_PM_ENTER:
620 			gic_dist_save(i);
621 			break;
622 		case CPU_CLUSTER_PM_ENTER_FAILED:
623 		case CPU_CLUSTER_PM_EXIT:
624 			gic_dist_restore(i);
625 			break;
626 		}
627 	}
628 
629 	return NOTIFY_OK;
630 }
631 
632 static struct notifier_block gic_notifier_block = {
633 	.notifier_call = gic_notifier,
634 };
635 
636 static void __init gic_pm_init(struct gic_chip_data *gic)
637 {
638 	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
639 		sizeof(u32));
640 	BUG_ON(!gic->saved_ppi_enable);
641 
642 	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
643 		sizeof(u32));
644 	BUG_ON(!gic->saved_ppi_conf);
645 
646 	if (gic == &gic_data[0])
647 		cpu_pm_register_notifier(&gic_notifier_block);
648 }
649 #else
650 static void __init gic_pm_init(struct gic_chip_data *gic)
651 {
652 }
653 #endif
654 
655 #ifdef CONFIG_SMP
656 static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
657 {
658 	int cpu;
659 	unsigned long flags, map = 0;
660 
661 	raw_spin_lock_irqsave(&irq_controller_lock, flags);
662 
663 	/* Convert our logical CPU mask into a physical one. */
664 	for_each_cpu(cpu, mask)
665 		map |= gic_cpu_map[cpu];
666 
667 	/*
668 	 * Ensure that stores to Normal memory are visible to the
669 	 * other CPUs before they observe us issuing the IPI.
670 	 */
671 	dmb(ishst);
672 
673 	/* this always happens on GIC0 */
674 	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
675 
676 	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
677 }
678 #endif
679 
680 #ifdef CONFIG_BL_SWITCHER
681 /*
682  * gic_send_sgi - send a SGI directly to given CPU interface number
683  *
684  * cpu_id: the ID for the destination CPU interface
685  * irq: the IPI number to send a SGI for
686  */
687 void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
688 {
689 	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
690 	cpu_id = 1 << cpu_id;
691 	/* this always happens on GIC0 */
692 	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
693 }
694 
695 /*
696  * gic_get_cpu_id - get the CPU interface ID for the specified CPU
697  *
698  * @cpu: the logical CPU number to get the GIC ID for.
699  *
700  * Return the CPU interface ID for the given logical CPU number,
701  * or -1 if the CPU number is too large or the interface ID is
702  * unknown (more than one bit set).
703  */
704 int gic_get_cpu_id(unsigned int cpu)
705 {
706 	unsigned int cpu_bit;
707 
708 	if (cpu >= NR_GIC_CPU_IF)
709 		return -1;
710 	cpu_bit = gic_cpu_map[cpu];
711 	if (cpu_bit & (cpu_bit - 1))
712 		return -1;
713 	return __ffs(cpu_bit);
714 }
715 
716 /*
717  * gic_migrate_target - migrate IRQs to another CPU interface
718  *
719  * @new_cpu_id: the CPU target ID to migrate IRQs to
720  *
721  * Migrate all peripheral interrupts with a target matching the current CPU
722  * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
723  * is also updated.  Targets to other CPU interfaces are unchanged.
724  * This must be called with IRQs locally disabled.
725  */
726 void gic_migrate_target(unsigned int new_cpu_id)
727 {
728 	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
729 	void __iomem *dist_base;
730 	int i, ror_val, cpu = smp_processor_id();
731 	u32 val, cur_target_mask, active_mask;
732 
733 	if (gic_nr >= MAX_GIC_NR)
734 		BUG();
735 
736 	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
737 	if (!dist_base)
738 		return;
739 	gic_irqs = gic_data[gic_nr].gic_irqs;
740 
741 	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
742 	cur_target_mask = 0x01010101 << cur_cpu_id;
743 	ror_val = (cur_cpu_id - new_cpu_id) & 31;
744 
745 	raw_spin_lock(&irq_controller_lock);
746 
747 	/* Update the target interface for this logical CPU */
748 	gic_cpu_map[cpu] = 1 << new_cpu_id;
749 
750 	/*
751 	 * Find all the peripheral interrupts targetting the current
752 	 * CPU interface and migrate them to the new CPU interface.
753 	 * We skip DIST_TARGET 0 to 7 as they are read-only.
754 	 */
755 	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
756 		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
757 		active_mask = val & cur_target_mask;
758 		if (active_mask) {
759 			val &= ~active_mask;
760 			val |= ror32(active_mask, ror_val);
761 			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
762 		}
763 	}
764 
765 	raw_spin_unlock(&irq_controller_lock);
766 
767 	/*
768 	 * Now let's migrate and clear any potential SGIs that might be
769 	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
770 	 * is a banked register, we can only forward the SGI using
771 	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
772 	 * doesn't use that information anyway.
773 	 *
774 	 * For the same reason we do not adjust SGI source information
775 	 * for previously sent SGIs by us to other CPUs either.
776 	 */
777 	for (i = 0; i < 16; i += 4) {
778 		int j;
779 		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
780 		if (!val)
781 			continue;
782 		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
783 		for (j = i; j < i + 4; j++) {
784 			if (val & 0xff)
785 				writel_relaxed((1 << (new_cpu_id + 16)) | j,
786 						dist_base + GIC_DIST_SOFTINT);
787 			val >>= 8;
788 		}
789 	}
790 }
791 
792 /*
793  * gic_get_sgir_physaddr - get the physical address for the SGI register
794  *
795  * REturn the physical address of the SGI register to be used
796  * by some early assembly code when the kernel is not yet available.
797  */
798 static unsigned long gic_dist_physaddr;
799 
800 unsigned long gic_get_sgir_physaddr(void)
801 {
802 	if (!gic_dist_physaddr)
803 		return 0;
804 	return gic_dist_physaddr + GIC_DIST_SOFTINT;
805 }
806 
807 void __init gic_init_physaddr(struct device_node *node)
808 {
809 	struct resource res;
810 	if (of_address_to_resource(node, 0, &res) == 0) {
811 		gic_dist_physaddr = res.start;
812 		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
813 	}
814 }
815 
816 #else
817 #define gic_init_physaddr(node)  do { } while (0)
818 #endif
819 
820 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
821 				irq_hw_number_t hw)
822 {
823 	if (hw < 32) {
824 		irq_set_percpu_devid(irq);
825 		irq_set_chip_and_handler(irq, &gic_chip,
826 					 handle_percpu_devid_irq);
827 		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
828 	} else {
829 		irq_set_chip_and_handler(irq, &gic_chip,
830 					 handle_fasteoi_irq);
831 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
832 
833 		gic_routable_irq_domain_ops->map(d, irq, hw);
834 	}
835 	irq_set_chip_data(irq, d->host_data);
836 	return 0;
837 }
838 
839 static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
840 {
841 	gic_routable_irq_domain_ops->unmap(d, irq);
842 }
843 
844 static int gic_irq_domain_xlate(struct irq_domain *d,
845 				struct device_node *controller,
846 				const u32 *intspec, unsigned int intsize,
847 				unsigned long *out_hwirq, unsigned int *out_type)
848 {
849 	unsigned long ret = 0;
850 
851 	if (d->of_node != controller)
852 		return -EINVAL;
853 	if (intsize < 3)
854 		return -EINVAL;
855 
856 	/* Get the interrupt number and add 16 to skip over SGIs */
857 	*out_hwirq = intspec[1] + 16;
858 
859 	/* For SPIs, we need to add 16 more to get the GIC irq ID number */
860 	if (!intspec[0]) {
861 		ret = gic_routable_irq_domain_ops->xlate(d, controller,
862 							 intspec,
863 							 intsize,
864 							 out_hwirq,
865 							 out_type);
866 
867 		if (IS_ERR_VALUE(ret))
868 			return ret;
869 	}
870 
871 	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
872 
873 	return ret;
874 }
875 
876 #ifdef CONFIG_SMP
877 static int gic_secondary_init(struct notifier_block *nfb, unsigned long action,
878 			      void *hcpu)
879 {
880 	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
881 		gic_cpu_init(&gic_data[0]);
882 	return NOTIFY_OK;
883 }
884 
885 /*
886  * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
887  * priority because the GIC needs to be up before the ARM generic timers.
888  */
889 static struct notifier_block gic_cpu_notifier = {
890 	.notifier_call = gic_secondary_init,
891 	.priority = 100,
892 };
893 #endif
894 
895 static const struct irq_domain_ops gic_irq_domain_ops = {
896 	.map = gic_irq_domain_map,
897 	.unmap = gic_irq_domain_unmap,
898 	.xlate = gic_irq_domain_xlate,
899 };
900 
901 /* Default functions for routable irq domain */
902 static int gic_routable_irq_domain_map(struct irq_domain *d, unsigned int irq,
903 			      irq_hw_number_t hw)
904 {
905 	return 0;
906 }
907 
908 static void gic_routable_irq_domain_unmap(struct irq_domain *d,
909 					  unsigned int irq)
910 {
911 }
912 
913 static int gic_routable_irq_domain_xlate(struct irq_domain *d,
914 				struct device_node *controller,
915 				const u32 *intspec, unsigned int intsize,
916 				unsigned long *out_hwirq,
917 				unsigned int *out_type)
918 {
919 	*out_hwirq += 16;
920 	return 0;
921 }
922 
923 const struct irq_domain_ops gic_default_routable_irq_domain_ops = {
924 	.map = gic_routable_irq_domain_map,
925 	.unmap = gic_routable_irq_domain_unmap,
926 	.xlate = gic_routable_irq_domain_xlate,
927 };
928 
929 const struct irq_domain_ops *gic_routable_irq_domain_ops =
930 					&gic_default_routable_irq_domain_ops;
931 
932 void __init gic_init_bases(unsigned int gic_nr, int irq_start,
933 			   void __iomem *dist_base, void __iomem *cpu_base,
934 			   u32 percpu_offset, struct device_node *node)
935 {
936 	irq_hw_number_t hwirq_base;
937 	struct gic_chip_data *gic;
938 	int gic_irqs, irq_base, i;
939 	int nr_routable_irqs;
940 
941 	BUG_ON(gic_nr >= MAX_GIC_NR);
942 
943 	gic = &gic_data[gic_nr];
944 #ifdef CONFIG_GIC_NON_BANKED
945 	if (percpu_offset) { /* Frankein-GIC without banked registers... */
946 		unsigned int cpu;
947 
948 		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
949 		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
950 		if (WARN_ON(!gic->dist_base.percpu_base ||
951 			    !gic->cpu_base.percpu_base)) {
952 			free_percpu(gic->dist_base.percpu_base);
953 			free_percpu(gic->cpu_base.percpu_base);
954 			return;
955 		}
956 
957 		for_each_possible_cpu(cpu) {
958 			u32 mpidr = cpu_logical_map(cpu);
959 			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
960 			unsigned long offset = percpu_offset * core_id;
961 			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) = dist_base + offset;
962 			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) = cpu_base + offset;
963 		}
964 
965 		gic_set_base_accessor(gic, gic_get_percpu_base);
966 	} else
967 #endif
968 	{			/* Normal, sane GIC... */
969 		WARN(percpu_offset,
970 		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
971 		     percpu_offset);
972 		gic->dist_base.common_base = dist_base;
973 		gic->cpu_base.common_base = cpu_base;
974 		gic_set_base_accessor(gic, gic_get_common_base);
975 	}
976 
977 	/*
978 	 * Initialize the CPU interface map to all CPUs.
979 	 * It will be refined as each CPU probes its ID.
980 	 */
981 	for (i = 0; i < NR_GIC_CPU_IF; i++)
982 		gic_cpu_map[i] = 0xff;
983 
984 	/*
985 	 * For primary GICs, skip over SGIs.
986 	 * For secondary GICs, skip over PPIs, too.
987 	 */
988 	if (gic_nr == 0 && (irq_start & 31) > 0) {
989 		hwirq_base = 16;
990 		if (irq_start != -1)
991 			irq_start = (irq_start & ~31) + 16;
992 	} else {
993 		hwirq_base = 32;
994 	}
995 
996 	/*
997 	 * Find out how many interrupts are supported.
998 	 * The GIC only supports up to 1020 interrupt sources.
999 	 */
1000 	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
1001 	gic_irqs = (gic_irqs + 1) * 32;
1002 	if (gic_irqs > 1020)
1003 		gic_irqs = 1020;
1004 	gic->gic_irqs = gic_irqs;
1005 
1006 	gic_irqs -= hwirq_base; /* calculate # of irqs to allocate */
1007 
1008 	if (of_property_read_u32(node, "arm,routable-irqs",
1009 				 &nr_routable_irqs)) {
1010 		irq_base = irq_alloc_descs(irq_start, 16, gic_irqs,
1011 					   numa_node_id());
1012 		if (IS_ERR_VALUE(irq_base)) {
1013 			WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
1014 			     irq_start);
1015 			irq_base = irq_start;
1016 		}
1017 
1018 		gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base,
1019 					hwirq_base, &gic_irq_domain_ops, gic);
1020 	} else {
1021 		gic->domain = irq_domain_add_linear(node, nr_routable_irqs,
1022 						    &gic_irq_domain_ops,
1023 						    gic);
1024 	}
1025 
1026 	if (WARN_ON(!gic->domain))
1027 		return;
1028 
1029 	if (gic_nr == 0) {
1030 #ifdef CONFIG_SMP
1031 		set_smp_cross_call(gic_raise_softirq);
1032 		register_cpu_notifier(&gic_cpu_notifier);
1033 #endif
1034 		set_handle_irq(gic_handle_irq);
1035 	}
1036 
1037 	gic_chip.flags |= gic_arch_extn.flags;
1038 	gic_dist_init(gic);
1039 	gic_cpu_init(gic);
1040 	gic_pm_init(gic);
1041 }
1042 
1043 #ifdef CONFIG_OF
1044 static int gic_cnt __initdata;
1045 
1046 static int __init
1047 gic_of_init(struct device_node *node, struct device_node *parent)
1048 {
1049 	void __iomem *cpu_base;
1050 	void __iomem *dist_base;
1051 	u32 percpu_offset;
1052 	int irq;
1053 
1054 	if (WARN_ON(!node))
1055 		return -ENODEV;
1056 
1057 	dist_base = of_iomap(node, 0);
1058 	WARN(!dist_base, "unable to map gic dist registers\n");
1059 
1060 	cpu_base = of_iomap(node, 1);
1061 	WARN(!cpu_base, "unable to map gic cpu registers\n");
1062 
1063 	if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
1064 		percpu_offset = 0;
1065 
1066 	gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
1067 	if (!gic_cnt)
1068 		gic_init_physaddr(node);
1069 
1070 	if (parent) {
1071 		irq = irq_of_parse_and_map(node, 0);
1072 		gic_cascade_irq(gic_cnt, irq);
1073 	}
1074 	gic_cnt++;
1075 	return 0;
1076 }
1077 IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1078 IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1079 IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1080 IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1081 IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1082 IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1083 
1084 #endif
1085