1/*
2 *  Copyright (C) 2002 ARM Limited, All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * Interrupt architecture for the GIC:
9 *
10 * o There is one Interrupt Distributor, which receives interrupts
11 *   from system devices and sends them to the Interrupt Controllers.
12 *
13 * o There is one CPU Interface per CPU, which sends interrupts sent
14 *   by the Distributor, and interrupts generated locally, to the
15 *   associated CPU. The base address of the CPU interface is usually
16 *   aliased so that the same address points to different chips depending
17 *   on the CPU it is accessed from.
18 *
19 * Note that IRQs 0-31 are special - they are local to each CPU.
20 * As such, the enable set/clear, pending set/clear and active bit
21 * registers are banked per-cpu for these sources.
22 */
23#include <linux/init.h>
24#include <linux/kernel.h>
25#include <linux/err.h>
26#include <linux/module.h>
27#include <linux/list.h>
28#include <linux/smp.h>
29#include <linux/cpu.h>
30#include <linux/cpu_pm.h>
31#include <linux/cpumask.h>
32#include <linux/io.h>
33#include <linux/of.h>
34#include <linux/of_address.h>
35#include <linux/of_irq.h>
36#include <linux/acpi.h>
37#include <linux/irqdomain.h>
38#include <linux/interrupt.h>
39#include <linux/percpu.h>
40#include <linux/slab.h>
41#include <linux/irqchip/chained_irq.h>
42#include <linux/irqchip/arm-gic.h>
43#include <linux/irqchip/arm-gic-acpi.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 "irq-gic-common.h"
51#include "irqchip.h"
52
53union gic_base {
54	void __iomem *common_base;
55	void __percpu * __iomem *percpu_base;
56};
57
58struct gic_chip_data {
59	union gic_base dist_base;
60	union gic_base cpu_base;
61#ifdef CONFIG_CPU_PM
62	u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)];
63	u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)];
64	u32 saved_spi_target[DIV_ROUND_UP(1020, 4)];
65	u32 __percpu *saved_ppi_enable;
66	u32 __percpu *saved_ppi_conf;
67#endif
68	struct irq_domain *domain;
69	unsigned int gic_irqs;
70#ifdef CONFIG_GIC_NON_BANKED
71	void __iomem *(*get_base)(union gic_base *);
72#endif
73};
74
75static DEFINE_RAW_SPINLOCK(irq_controller_lock);
76
77/*
78 * The GIC mapping of CPU interfaces does not necessarily match
79 * the logical CPU numbering.  Let's use a mapping as returned
80 * by the GIC itself.
81 */
82#define NR_GIC_CPU_IF 8
83static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
84
85#ifndef MAX_GIC_NR
86#define MAX_GIC_NR	1
87#endif
88
89static struct gic_chip_data gic_data[MAX_GIC_NR] __read_mostly;
90
91#ifdef CONFIG_GIC_NON_BANKED
92static void __iomem *gic_get_percpu_base(union gic_base *base)
93{
94	return raw_cpu_read(*base->percpu_base);
95}
96
97static void __iomem *gic_get_common_base(union gic_base *base)
98{
99	return base->common_base;
100}
101
102static inline void __iomem *gic_data_dist_base(struct gic_chip_data *data)
103{
104	return data->get_base(&data->dist_base);
105}
106
107static inline void __iomem *gic_data_cpu_base(struct gic_chip_data *data)
108{
109	return data->get_base(&data->cpu_base);
110}
111
112static inline void gic_set_base_accessor(struct gic_chip_data *data,
113					 void __iomem *(*f)(union gic_base *))
114{
115	data->get_base = f;
116}
117#else
118#define gic_data_dist_base(d)	((d)->dist_base.common_base)
119#define gic_data_cpu_base(d)	((d)->cpu_base.common_base)
120#define gic_set_base_accessor(d, f)
121#endif
122
123static inline void __iomem *gic_dist_base(struct irq_data *d)
124{
125	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
126	return gic_data_dist_base(gic_data);
127}
128
129static inline void __iomem *gic_cpu_base(struct irq_data *d)
130{
131	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
132	return gic_data_cpu_base(gic_data);
133}
134
135static inline unsigned int gic_irq(struct irq_data *d)
136{
137	return d->hwirq;
138}
139
140/*
141 * Routines to acknowledge, disable and enable interrupts
142 */
143static void gic_poke_irq(struct irq_data *d, u32 offset)
144{
145	u32 mask = 1 << (gic_irq(d) % 32);
146	writel_relaxed(mask, gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4);
147}
148
149static int gic_peek_irq(struct irq_data *d, u32 offset)
150{
151	u32 mask = 1 << (gic_irq(d) % 32);
152	return !!(readl_relaxed(gic_dist_base(d) + offset + (gic_irq(d) / 32) * 4) & mask);
153}
154
155static void gic_mask_irq(struct irq_data *d)
156{
157	gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
158}
159
160static void gic_unmask_irq(struct irq_data *d)
161{
162	gic_poke_irq(d, GIC_DIST_ENABLE_SET);
163}
164
165static void gic_eoi_irq(struct irq_data *d)
166{
167	writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
168}
169
170static int gic_irq_set_irqchip_state(struct irq_data *d,
171				     enum irqchip_irq_state which, bool val)
172{
173	u32 reg;
174
175	switch (which) {
176	case IRQCHIP_STATE_PENDING:
177		reg = val ? GIC_DIST_PENDING_SET : GIC_DIST_PENDING_CLEAR;
178		break;
179
180	case IRQCHIP_STATE_ACTIVE:
181		reg = val ? GIC_DIST_ACTIVE_SET : GIC_DIST_ACTIVE_CLEAR;
182		break;
183
184	case IRQCHIP_STATE_MASKED:
185		reg = val ? GIC_DIST_ENABLE_CLEAR : GIC_DIST_ENABLE_SET;
186		break;
187
188	default:
189		return -EINVAL;
190	}
191
192	gic_poke_irq(d, reg);
193	return 0;
194}
195
196static int gic_irq_get_irqchip_state(struct irq_data *d,
197				      enum irqchip_irq_state which, bool *val)
198{
199	switch (which) {
200	case IRQCHIP_STATE_PENDING:
201		*val = gic_peek_irq(d, GIC_DIST_PENDING_SET);
202		break;
203
204	case IRQCHIP_STATE_ACTIVE:
205		*val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET);
206		break;
207
208	case IRQCHIP_STATE_MASKED:
209		*val = !gic_peek_irq(d, GIC_DIST_ENABLE_SET);
210		break;
211
212	default:
213		return -EINVAL;
214	}
215
216	return 0;
217}
218
219static int gic_set_type(struct irq_data *d, unsigned int type)
220{
221	void __iomem *base = gic_dist_base(d);
222	unsigned int gicirq = gic_irq(d);
223
224	/* Interrupt configuration for SGIs can't be changed */
225	if (gicirq < 16)
226		return -EINVAL;
227
228	/* SPIs have restrictions on the supported types */
229	if (gicirq >= 32 && type != IRQ_TYPE_LEVEL_HIGH &&
230			    type != IRQ_TYPE_EDGE_RISING)
231		return -EINVAL;
232
233	return gic_configure_irq(gicirq, type, base, NULL);
234}
235
236#ifdef CONFIG_SMP
237static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
238			    bool force)
239{
240	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
241	unsigned int cpu, shift = (gic_irq(d) % 4) * 8;
242	u32 val, mask, bit;
243	unsigned long flags;
244
245	if (!force)
246		cpu = cpumask_any_and(mask_val, cpu_online_mask);
247	else
248		cpu = cpumask_first(mask_val);
249
250	if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
251		return -EINVAL;
252
253	raw_spin_lock_irqsave(&irq_controller_lock, flags);
254	mask = 0xff << shift;
255	bit = gic_cpu_map[cpu] << shift;
256	val = readl_relaxed(reg) & ~mask;
257	writel_relaxed(val | bit, reg);
258	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
259
260	return IRQ_SET_MASK_OK;
261}
262#endif
263
264static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
265{
266	u32 irqstat, irqnr;
267	struct gic_chip_data *gic = &gic_data[0];
268	void __iomem *cpu_base = gic_data_cpu_base(gic);
269
270	do {
271		irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK);
272		irqnr = irqstat & GICC_IAR_INT_ID_MASK;
273
274		if (likely(irqnr > 15 && irqnr < 1021)) {
275			handle_domain_irq(gic->domain, irqnr, regs);
276			continue;
277		}
278		if (irqnr < 16) {
279			writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
280#ifdef CONFIG_SMP
281			/*
282			 * Ensure any shared data written by the CPU sending
283			 * the IPI is read after we've read the ACK register
284			 * on the GIC.
285			 *
286			 * Pairs with the write barrier in gic_raise_softirq
287			 */
288			smp_rmb();
289			handle_IPI(irqnr, regs);
290#endif
291			continue;
292		}
293		break;
294	} while (1);
295}
296
297static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
298{
299	struct gic_chip_data *chip_data = irq_get_handler_data(irq);
300	struct irq_chip *chip = irq_get_chip(irq);
301	unsigned int cascade_irq, gic_irq;
302	unsigned long status;
303
304	chained_irq_enter(chip, desc);
305
306	raw_spin_lock(&irq_controller_lock);
307	status = readl_relaxed(gic_data_cpu_base(chip_data) + GIC_CPU_INTACK);
308	raw_spin_unlock(&irq_controller_lock);
309
310	gic_irq = (status & GICC_IAR_INT_ID_MASK);
311	if (gic_irq == GICC_INT_SPURIOUS)
312		goto out;
313
314	cascade_irq = irq_find_mapping(chip_data->domain, gic_irq);
315	if (unlikely(gic_irq < 32 || gic_irq > 1020))
316		handle_bad_irq(cascade_irq, desc);
317	else
318		generic_handle_irq(cascade_irq);
319
320 out:
321	chained_irq_exit(chip, desc);
322}
323
324static struct irq_chip gic_chip = {
325	.name			= "GIC",
326	.irq_mask		= gic_mask_irq,
327	.irq_unmask		= gic_unmask_irq,
328	.irq_eoi		= gic_eoi_irq,
329	.irq_set_type		= gic_set_type,
330#ifdef CONFIG_SMP
331	.irq_set_affinity	= gic_set_affinity,
332#endif
333	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
334	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
335};
336
337void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
338{
339	if (gic_nr >= MAX_GIC_NR)
340		BUG();
341	if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
342		BUG();
343	irq_set_chained_handler(irq, gic_handle_cascade_irq);
344}
345
346static u8 gic_get_cpumask(struct gic_chip_data *gic)
347{
348	void __iomem *base = gic_data_dist_base(gic);
349	u32 mask, i;
350
351	for (i = mask = 0; i < 32; i += 4) {
352		mask = readl_relaxed(base + GIC_DIST_TARGET + i);
353		mask |= mask >> 16;
354		mask |= mask >> 8;
355		if (mask)
356			break;
357	}
358
359	if (!mask && num_possible_cpus() > 1)
360		pr_crit("GIC CPU mask not found - kernel will fail to boot.\n");
361
362	return mask;
363}
364
365static void gic_cpu_if_up(void)
366{
367	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
368	u32 bypass = 0;
369
370	/*
371	* Preserve bypass disable bits to be written back later
372	*/
373	bypass = readl(cpu_base + GIC_CPU_CTRL);
374	bypass &= GICC_DIS_BYPASS_MASK;
375
376	writel_relaxed(bypass | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
377}
378
379
380static 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(GICD_DISABLE, base + GIC_DIST_CTRL);
388
389	/*
390	 * Set all global interrupts to this CPU only.
391	 */
392	cpumask = gic_get_cpumask(gic);
393	cpumask |= cpumask << 8;
394	cpumask |= cpumask << 16;
395	for (i = 32; i < gic_irqs; i += 4)
396		writel_relaxed(cpumask, base + GIC_DIST_TARGET + i * 4 / 4);
397
398	gic_dist_config(base, gic_irqs, NULL);
399
400	writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL);
401}
402
403static void gic_cpu_init(struct gic_chip_data *gic)
404{
405	void __iomem *dist_base = gic_data_dist_base(gic);
406	void __iomem *base = gic_data_cpu_base(gic);
407	unsigned int cpu_mask, cpu = smp_processor_id();
408	int i;
409
410	/*
411	 * Get what the GIC says our CPU mask is.
412	 */
413	BUG_ON(cpu >= NR_GIC_CPU_IF);
414	cpu_mask = gic_get_cpumask(gic);
415	gic_cpu_map[cpu] = cpu_mask;
416
417	/*
418	 * Clear our mask from the other map entries in case they're
419	 * still undefined.
420	 */
421	for (i = 0; i < NR_GIC_CPU_IF; i++)
422		if (i != cpu)
423			gic_cpu_map[i] &= ~cpu_mask;
424
425	gic_cpu_config(dist_base, NULL);
426
427	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
428	gic_cpu_if_up();
429}
430
431void gic_cpu_if_down(void)
432{
433	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
434	u32 val = 0;
435
436	val = readl(cpu_base + GIC_CPU_CTRL);
437	val &= ~GICC_ENABLE;
438	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
439}
440
441#ifdef CONFIG_CPU_PM
442/*
443 * Saves the GIC distributor registers during suspend or idle.  Must be called
444 * with interrupts disabled but before powering down the GIC.  After calling
445 * this function, no interrupts will be delivered by the GIC, and another
446 * platform-specific wakeup source must be enabled.
447 */
448static void gic_dist_save(unsigned int gic_nr)
449{
450	unsigned int gic_irqs;
451	void __iomem *dist_base;
452	int i;
453
454	if (gic_nr >= MAX_GIC_NR)
455		BUG();
456
457	gic_irqs = gic_data[gic_nr].gic_irqs;
458	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
459
460	if (!dist_base)
461		return;
462
463	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
464		gic_data[gic_nr].saved_spi_conf[i] =
465			readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
466
467	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
468		gic_data[gic_nr].saved_spi_target[i] =
469			readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
470
471	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
472		gic_data[gic_nr].saved_spi_enable[i] =
473			readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
474}
475
476/*
477 * Restores the GIC distributor registers during resume or when coming out of
478 * idle.  Must be called before enabling interrupts.  If a level interrupt
479 * that occured while the GIC was suspended is still present, it will be
480 * handled normally, but any edge interrupts that occured will not be seen by
481 * the GIC and need to be handled by the platform-specific wakeup source.
482 */
483static void gic_dist_restore(unsigned int gic_nr)
484{
485	unsigned int gic_irqs;
486	unsigned int i;
487	void __iomem *dist_base;
488
489	if (gic_nr >= MAX_GIC_NR)
490		BUG();
491
492	gic_irqs = gic_data[gic_nr].gic_irqs;
493	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
494
495	if (!dist_base)
496		return;
497
498	writel_relaxed(GICD_DISABLE, dist_base + GIC_DIST_CTRL);
499
500	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 16); i++)
501		writel_relaxed(gic_data[gic_nr].saved_spi_conf[i],
502			dist_base + GIC_DIST_CONFIG + i * 4);
503
504	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
505		writel_relaxed(GICD_INT_DEF_PRI_X4,
506			dist_base + GIC_DIST_PRI + i * 4);
507
508	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 4); i++)
509		writel_relaxed(gic_data[gic_nr].saved_spi_target[i],
510			dist_base + GIC_DIST_TARGET + i * 4);
511
512	for (i = 0; i < DIV_ROUND_UP(gic_irqs, 32); i++)
513		writel_relaxed(gic_data[gic_nr].saved_spi_enable[i],
514			dist_base + GIC_DIST_ENABLE_SET + i * 4);
515
516	writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL);
517}
518
519static void gic_cpu_save(unsigned int gic_nr)
520{
521	int i;
522	u32 *ptr;
523	void __iomem *dist_base;
524	void __iomem *cpu_base;
525
526	if (gic_nr >= MAX_GIC_NR)
527		BUG();
528
529	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
530	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
531
532	if (!dist_base || !cpu_base)
533		return;
534
535	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
536	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
537		ptr[i] = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
538
539	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
540	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
541		ptr[i] = readl_relaxed(dist_base + GIC_DIST_CONFIG + i * 4);
542
543}
544
545static void gic_cpu_restore(unsigned int gic_nr)
546{
547	int i;
548	u32 *ptr;
549	void __iomem *dist_base;
550	void __iomem *cpu_base;
551
552	if (gic_nr >= MAX_GIC_NR)
553		BUG();
554
555	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
556	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
557
558	if (!dist_base || !cpu_base)
559		return;
560
561	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_enable);
562	for (i = 0; i < DIV_ROUND_UP(32, 32); i++)
563		writel_relaxed(ptr[i], dist_base + GIC_DIST_ENABLE_SET + i * 4);
564
565	ptr = raw_cpu_ptr(gic_data[gic_nr].saved_ppi_conf);
566	for (i = 0; i < DIV_ROUND_UP(32, 16); i++)
567		writel_relaxed(ptr[i], dist_base + GIC_DIST_CONFIG + i * 4);
568
569	for (i = 0; i < DIV_ROUND_UP(32, 4); i++)
570		writel_relaxed(GICD_INT_DEF_PRI_X4,
571					dist_base + GIC_DIST_PRI + i * 4);
572
573	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
574	gic_cpu_if_up();
575}
576
577static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
578{
579	int i;
580
581	for (i = 0; i < MAX_GIC_NR; i++) {
582#ifdef CONFIG_GIC_NON_BANKED
583		/* Skip over unused GICs */
584		if (!gic_data[i].get_base)
585			continue;
586#endif
587		switch (cmd) {
588		case CPU_PM_ENTER:
589			gic_cpu_save(i);
590			break;
591		case CPU_PM_ENTER_FAILED:
592		case CPU_PM_EXIT:
593			gic_cpu_restore(i);
594			break;
595		case CPU_CLUSTER_PM_ENTER:
596			gic_dist_save(i);
597			break;
598		case CPU_CLUSTER_PM_ENTER_FAILED:
599		case CPU_CLUSTER_PM_EXIT:
600			gic_dist_restore(i);
601			break;
602		}
603	}
604
605	return NOTIFY_OK;
606}
607
608static struct notifier_block gic_notifier_block = {
609	.notifier_call = gic_notifier,
610};
611
612static void __init gic_pm_init(struct gic_chip_data *gic)
613{
614	gic->saved_ppi_enable = __alloc_percpu(DIV_ROUND_UP(32, 32) * 4,
615		sizeof(u32));
616	BUG_ON(!gic->saved_ppi_enable);
617
618	gic->saved_ppi_conf = __alloc_percpu(DIV_ROUND_UP(32, 16) * 4,
619		sizeof(u32));
620	BUG_ON(!gic->saved_ppi_conf);
621
622	if (gic == &gic_data[0])
623		cpu_pm_register_notifier(&gic_notifier_block);
624}
625#else
626static void __init gic_pm_init(struct gic_chip_data *gic)
627{
628}
629#endif
630
631#ifdef CONFIG_SMP
632static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
633{
634	int cpu;
635	unsigned long flags, map = 0;
636
637	raw_spin_lock_irqsave(&irq_controller_lock, flags);
638
639	/* Convert our logical CPU mask into a physical one. */
640	for_each_cpu(cpu, mask)
641		map |= gic_cpu_map[cpu];
642
643	/*
644	 * Ensure that stores to Normal memory are visible to the
645	 * other CPUs before they observe us issuing the IPI.
646	 */
647	dmb(ishst);
648
649	/* this always happens on GIC0 */
650	writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
651
652	raw_spin_unlock_irqrestore(&irq_controller_lock, flags);
653}
654#endif
655
656#ifdef CONFIG_BL_SWITCHER
657/*
658 * gic_send_sgi - send a SGI directly to given CPU interface number
659 *
660 * cpu_id: the ID for the destination CPU interface
661 * irq: the IPI number to send a SGI for
662 */
663void gic_send_sgi(unsigned int cpu_id, unsigned int irq)
664{
665	BUG_ON(cpu_id >= NR_GIC_CPU_IF);
666	cpu_id = 1 << cpu_id;
667	/* this always happens on GIC0 */
668	writel_relaxed((cpu_id << 16) | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT);
669}
670
671/*
672 * gic_get_cpu_id - get the CPU interface ID for the specified CPU
673 *
674 * @cpu: the logical CPU number to get the GIC ID for.
675 *
676 * Return the CPU interface ID for the given logical CPU number,
677 * or -1 if the CPU number is too large or the interface ID is
678 * unknown (more than one bit set).
679 */
680int gic_get_cpu_id(unsigned int cpu)
681{
682	unsigned int cpu_bit;
683
684	if (cpu >= NR_GIC_CPU_IF)
685		return -1;
686	cpu_bit = gic_cpu_map[cpu];
687	if (cpu_bit & (cpu_bit - 1))
688		return -1;
689	return __ffs(cpu_bit);
690}
691
692/*
693 * gic_migrate_target - migrate IRQs to another CPU interface
694 *
695 * @new_cpu_id: the CPU target ID to migrate IRQs to
696 *
697 * Migrate all peripheral interrupts with a target matching the current CPU
698 * to the interface corresponding to @new_cpu_id.  The CPU interface mapping
699 * is also updated.  Targets to other CPU interfaces are unchanged.
700 * This must be called with IRQs locally disabled.
701 */
702void gic_migrate_target(unsigned int new_cpu_id)
703{
704	unsigned int cur_cpu_id, gic_irqs, gic_nr = 0;
705	void __iomem *dist_base;
706	int i, ror_val, cpu = smp_processor_id();
707	u32 val, cur_target_mask, active_mask;
708
709	if (gic_nr >= MAX_GIC_NR)
710		BUG();
711
712	dist_base = gic_data_dist_base(&gic_data[gic_nr]);
713	if (!dist_base)
714		return;
715	gic_irqs = gic_data[gic_nr].gic_irqs;
716
717	cur_cpu_id = __ffs(gic_cpu_map[cpu]);
718	cur_target_mask = 0x01010101 << cur_cpu_id;
719	ror_val = (cur_cpu_id - new_cpu_id) & 31;
720
721	raw_spin_lock(&irq_controller_lock);
722
723	/* Update the target interface for this logical CPU */
724	gic_cpu_map[cpu] = 1 << new_cpu_id;
725
726	/*
727	 * Find all the peripheral interrupts targetting the current
728	 * CPU interface and migrate them to the new CPU interface.
729	 * We skip DIST_TARGET 0 to 7 as they are read-only.
730	 */
731	for (i = 8; i < DIV_ROUND_UP(gic_irqs, 4); i++) {
732		val = readl_relaxed(dist_base + GIC_DIST_TARGET + i * 4);
733		active_mask = val & cur_target_mask;
734		if (active_mask) {
735			val &= ~active_mask;
736			val |= ror32(active_mask, ror_val);
737			writel_relaxed(val, dist_base + GIC_DIST_TARGET + i*4);
738		}
739	}
740
741	raw_spin_unlock(&irq_controller_lock);
742
743	/*
744	 * Now let's migrate and clear any potential SGIs that might be
745	 * pending for us (cur_cpu_id).  Since GIC_DIST_SGI_PENDING_SET
746	 * is a banked register, we can only forward the SGI using
747	 * GIC_DIST_SOFTINT.  The original SGI source is lost but Linux
748	 * doesn't use that information anyway.
749	 *
750	 * For the same reason we do not adjust SGI source information
751	 * for previously sent SGIs by us to other CPUs either.
752	 */
753	for (i = 0; i < 16; i += 4) {
754		int j;
755		val = readl_relaxed(dist_base + GIC_DIST_SGI_PENDING_SET + i);
756		if (!val)
757			continue;
758		writel_relaxed(val, dist_base + GIC_DIST_SGI_PENDING_CLEAR + i);
759		for (j = i; j < i + 4; j++) {
760			if (val & 0xff)
761				writel_relaxed((1 << (new_cpu_id + 16)) | j,
762						dist_base + GIC_DIST_SOFTINT);
763			val >>= 8;
764		}
765	}
766}
767
768/*
769 * gic_get_sgir_physaddr - get the physical address for the SGI register
770 *
771 * REturn the physical address of the SGI register to be used
772 * by some early assembly code when the kernel is not yet available.
773 */
774static unsigned long gic_dist_physaddr;
775
776unsigned long gic_get_sgir_physaddr(void)
777{
778	if (!gic_dist_physaddr)
779		return 0;
780	return gic_dist_physaddr + GIC_DIST_SOFTINT;
781}
782
783void __init gic_init_physaddr(struct device_node *node)
784{
785	struct resource res;
786	if (of_address_to_resource(node, 0, &res) == 0) {
787		gic_dist_physaddr = res.start;
788		pr_info("GIC physical location is %#lx\n", gic_dist_physaddr);
789	}
790}
791
792#else
793#define gic_init_physaddr(node)  do { } while (0)
794#endif
795
796static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
797				irq_hw_number_t hw)
798{
799	if (hw < 32) {
800		irq_set_percpu_devid(irq);
801		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
802				    handle_percpu_devid_irq, NULL, NULL);
803		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
804	} else {
805		irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
806				    handle_fasteoi_irq, NULL, NULL);
807		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
808	}
809	return 0;
810}
811
812static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
813{
814}
815
816static int gic_irq_domain_xlate(struct irq_domain *d,
817				struct device_node *controller,
818				const u32 *intspec, unsigned int intsize,
819				unsigned long *out_hwirq, unsigned int *out_type)
820{
821	unsigned long ret = 0;
822
823	if (d->of_node != controller)
824		return -EINVAL;
825	if (intsize < 3)
826		return -EINVAL;
827
828	/* Get the interrupt number and add 16 to skip over SGIs */
829	*out_hwirq = intspec[1] + 16;
830
831	/* For SPIs, we need to add 16 more to get the GIC irq ID number */
832	if (!intspec[0])
833		*out_hwirq += 16;
834
835	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
836
837	return ret;
838}
839
840#ifdef CONFIG_SMP
841static int gic_secondary_init(struct notifier_block *nfb, unsigned long action,
842			      void *hcpu)
843{
844	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
845		gic_cpu_init(&gic_data[0]);
846	return NOTIFY_OK;
847}
848
849/*
850 * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
851 * priority because the GIC needs to be up before the ARM generic timers.
852 */
853static struct notifier_block gic_cpu_notifier = {
854	.notifier_call = gic_secondary_init,
855	.priority = 100,
856};
857#endif
858
859static int gic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
860				unsigned int nr_irqs, void *arg)
861{
862	int i, ret;
863	irq_hw_number_t hwirq;
864	unsigned int type = IRQ_TYPE_NONE;
865	struct of_phandle_args *irq_data = arg;
866
867	ret = gic_irq_domain_xlate(domain, irq_data->np, irq_data->args,
868				   irq_data->args_count, &hwirq, &type);
869	if (ret)
870		return ret;
871
872	for (i = 0; i < nr_irqs; i++)
873		gic_irq_domain_map(domain, virq + i, hwirq + i);
874
875	return 0;
876}
877
878static const struct irq_domain_ops gic_irq_domain_hierarchy_ops = {
879	.xlate = gic_irq_domain_xlate,
880	.alloc = gic_irq_domain_alloc,
881	.free = irq_domain_free_irqs_top,
882};
883
884static const struct irq_domain_ops gic_irq_domain_ops = {
885	.map = gic_irq_domain_map,
886	.unmap = gic_irq_domain_unmap,
887	.xlate = gic_irq_domain_xlate,
888};
889
890void gic_set_irqchip_flags(unsigned long flags)
891{
892	gic_chip.flags |= flags;
893}
894
895void __init gic_init_bases(unsigned int gic_nr, int irq_start,
896			   void __iomem *dist_base, void __iomem *cpu_base,
897			   u32 percpu_offset, struct device_node *node)
898{
899	irq_hw_number_t hwirq_base;
900	struct gic_chip_data *gic;
901	int gic_irqs, irq_base, i;
902
903	BUG_ON(gic_nr >= MAX_GIC_NR);
904
905	gic = &gic_data[gic_nr];
906#ifdef CONFIG_GIC_NON_BANKED
907	if (percpu_offset) { /* Frankein-GIC without banked registers... */
908		unsigned int cpu;
909
910		gic->dist_base.percpu_base = alloc_percpu(void __iomem *);
911		gic->cpu_base.percpu_base = alloc_percpu(void __iomem *);
912		if (WARN_ON(!gic->dist_base.percpu_base ||
913			    !gic->cpu_base.percpu_base)) {
914			free_percpu(gic->dist_base.percpu_base);
915			free_percpu(gic->cpu_base.percpu_base);
916			return;
917		}
918
919		for_each_possible_cpu(cpu) {
920			u32 mpidr = cpu_logical_map(cpu);
921			u32 core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
922			unsigned long offset = percpu_offset * core_id;
923			*per_cpu_ptr(gic->dist_base.percpu_base, cpu) = dist_base + offset;
924			*per_cpu_ptr(gic->cpu_base.percpu_base, cpu) = cpu_base + offset;
925		}
926
927		gic_set_base_accessor(gic, gic_get_percpu_base);
928	} else
929#endif
930	{			/* Normal, sane GIC... */
931		WARN(percpu_offset,
932		     "GIC_NON_BANKED not enabled, ignoring %08x offset!",
933		     percpu_offset);
934		gic->dist_base.common_base = dist_base;
935		gic->cpu_base.common_base = cpu_base;
936		gic_set_base_accessor(gic, gic_get_common_base);
937	}
938
939	/*
940	 * Initialize the CPU interface map to all CPUs.
941	 * It will be refined as each CPU probes its ID.
942	 */
943	for (i = 0; i < NR_GIC_CPU_IF; i++)
944		gic_cpu_map[i] = 0xff;
945
946	/*
947	 * Find out how many interrupts are supported.
948	 * The GIC only supports up to 1020 interrupt sources.
949	 */
950	gic_irqs = readl_relaxed(gic_data_dist_base(gic) + GIC_DIST_CTR) & 0x1f;
951	gic_irqs = (gic_irqs + 1) * 32;
952	if (gic_irqs > 1020)
953		gic_irqs = 1020;
954	gic->gic_irqs = gic_irqs;
955
956	if (node) {		/* DT case */
957		gic->domain = irq_domain_add_linear(node, gic_irqs,
958						    &gic_irq_domain_hierarchy_ops,
959						    gic);
960	} else {		/* Non-DT case */
961		/*
962		 * For primary GICs, skip over SGIs.
963		 * For secondary GICs, skip over PPIs, too.
964		 */
965		if (gic_nr == 0 && (irq_start & 31) > 0) {
966			hwirq_base = 16;
967			if (irq_start != -1)
968				irq_start = (irq_start & ~31) + 16;
969		} else {
970			hwirq_base = 32;
971		}
972
973		gic_irqs -= hwirq_base; /* calculate # of irqs to allocate */
974
975		irq_base = irq_alloc_descs(irq_start, 16, gic_irqs,
976					   numa_node_id());
977		if (IS_ERR_VALUE(irq_base)) {
978			WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
979			     irq_start);
980			irq_base = irq_start;
981		}
982
983		gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base,
984					hwirq_base, &gic_irq_domain_ops, gic);
985	}
986
987	if (WARN_ON(!gic->domain))
988		return;
989
990	if (gic_nr == 0) {
991#ifdef CONFIG_SMP
992		set_smp_cross_call(gic_raise_softirq);
993		register_cpu_notifier(&gic_cpu_notifier);
994#endif
995		set_handle_irq(gic_handle_irq);
996	}
997
998	gic_dist_init(gic);
999	gic_cpu_init(gic);
1000	gic_pm_init(gic);
1001}
1002
1003#ifdef CONFIG_OF
1004static int gic_cnt __initdata;
1005
1006static int __init
1007gic_of_init(struct device_node *node, struct device_node *parent)
1008{
1009	void __iomem *cpu_base;
1010	void __iomem *dist_base;
1011	u32 percpu_offset;
1012	int irq;
1013
1014	if (WARN_ON(!node))
1015		return -ENODEV;
1016
1017	dist_base = of_iomap(node, 0);
1018	WARN(!dist_base, "unable to map gic dist registers\n");
1019
1020	cpu_base = of_iomap(node, 1);
1021	WARN(!cpu_base, "unable to map gic cpu registers\n");
1022
1023	if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
1024		percpu_offset = 0;
1025
1026	gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
1027	if (!gic_cnt)
1028		gic_init_physaddr(node);
1029
1030	if (parent) {
1031		irq = irq_of_parse_and_map(node, 0);
1032		gic_cascade_irq(gic_cnt, irq);
1033	}
1034
1035	if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
1036		gicv2m_of_init(node, gic_data[gic_cnt].domain);
1037
1038	gic_cnt++;
1039	return 0;
1040}
1041IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init);
1042IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", gic_of_init);
1043IRQCHIP_DECLARE(arm1176jzf_dc_gic, "arm,arm1176jzf-devchip-gic", gic_of_init);
1044IRQCHIP_DECLARE(cortex_a15_gic, "arm,cortex-a15-gic", gic_of_init);
1045IRQCHIP_DECLARE(cortex_a9_gic, "arm,cortex-a9-gic", gic_of_init);
1046IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init);
1047IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init);
1048IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init);
1049
1050#endif
1051
1052#ifdef CONFIG_ACPI
1053static phys_addr_t dist_phy_base, cpu_phy_base __initdata;
1054
1055static int __init
1056gic_acpi_parse_madt_cpu(struct acpi_subtable_header *header,
1057			const unsigned long end)
1058{
1059	struct acpi_madt_generic_interrupt *processor;
1060	phys_addr_t gic_cpu_base;
1061	static int cpu_base_assigned;
1062
1063	processor = (struct acpi_madt_generic_interrupt *)header;
1064
1065	if (BAD_MADT_ENTRY(processor, end))
1066		return -EINVAL;
1067
1068	/*
1069	 * There is no support for non-banked GICv1/2 register in ACPI spec.
1070	 * All CPU interface addresses have to be the same.
1071	 */
1072	gic_cpu_base = processor->base_address;
1073	if (cpu_base_assigned && gic_cpu_base != cpu_phy_base)
1074		return -EINVAL;
1075
1076	cpu_phy_base = gic_cpu_base;
1077	cpu_base_assigned = 1;
1078	return 0;
1079}
1080
1081static int __init
1082gic_acpi_parse_madt_distributor(struct acpi_subtable_header *header,
1083				const unsigned long end)
1084{
1085	struct acpi_madt_generic_distributor *dist;
1086
1087	dist = (struct acpi_madt_generic_distributor *)header;
1088
1089	if (BAD_MADT_ENTRY(dist, end))
1090		return -EINVAL;
1091
1092	dist_phy_base = dist->base_address;
1093	return 0;
1094}
1095
1096int __init
1097gic_v2_acpi_init(struct acpi_table_header *table)
1098{
1099	void __iomem *cpu_base, *dist_base;
1100	int count;
1101
1102	/* Collect CPU base addresses */
1103	count = acpi_parse_entries(ACPI_SIG_MADT,
1104				   sizeof(struct acpi_table_madt),
1105				   gic_acpi_parse_madt_cpu, table,
1106				   ACPI_MADT_TYPE_GENERIC_INTERRUPT, 0);
1107	if (count <= 0) {
1108		pr_err("No valid GICC entries exist\n");
1109		return -EINVAL;
1110	}
1111
1112	/*
1113	 * Find distributor base address. We expect one distributor entry since
1114	 * ACPI 5.1 spec neither support multi-GIC instances nor GIC cascade.
1115	 */
1116	count = acpi_parse_entries(ACPI_SIG_MADT,
1117				   sizeof(struct acpi_table_madt),
1118				   gic_acpi_parse_madt_distributor, table,
1119				   ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR, 0);
1120	if (count <= 0) {
1121		pr_err("No valid GICD entries exist\n");
1122		return -EINVAL;
1123	} else if (count > 1) {
1124		pr_err("More than one GICD entry detected\n");
1125		return -EINVAL;
1126	}
1127
1128	cpu_base = ioremap(cpu_phy_base, ACPI_GIC_CPU_IF_MEM_SIZE);
1129	if (!cpu_base) {
1130		pr_err("Unable to map GICC registers\n");
1131		return -ENOMEM;
1132	}
1133
1134	dist_base = ioremap(dist_phy_base, ACPI_GICV2_DIST_MEM_SIZE);
1135	if (!dist_base) {
1136		pr_err("Unable to map GICD registers\n");
1137		iounmap(cpu_base);
1138		return -ENOMEM;
1139	}
1140
1141	/*
1142	 * Initialize zero GIC instance (no multi-GIC support). Also, set GIC
1143	 * as default IRQ domain to allow for GSI registration and GSI to IRQ
1144	 * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()).
1145	 */
1146	gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
1147	irq_set_default_host(gic_data[0].domain);
1148
1149	acpi_irq_model = ACPI_IRQ_MODEL_GIC;
1150	return 0;
1151}
1152#endif
1153