1/*
2 * Library implementing the most common irq chip callback functions
3 *
4 * Copyright (C) 2011, Thomas Gleixner
5 */
6#include <linux/io.h>
7#include <linux/irq.h>
8#include <linux/slab.h>
9#include <linux/export.h>
10#include <linux/irqdomain.h>
11#include <linux/interrupt.h>
12#include <linux/kernel_stat.h>
13#include <linux/syscore_ops.h>
14
15#include "internals.h"
16
17static LIST_HEAD(gc_list);
18static DEFINE_RAW_SPINLOCK(gc_lock);
19
20/**
21 * irq_gc_noop - NOOP function
22 * @d: irq_data
23 */
24void irq_gc_noop(struct irq_data *d)
25{
26}
27
28/**
29 * irq_gc_mask_disable_reg - Mask chip via disable register
30 * @d: irq_data
31 *
32 * Chip has separate enable/disable registers instead of a single mask
33 * register.
34 */
35void irq_gc_mask_disable_reg(struct irq_data *d)
36{
37	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
38	struct irq_chip_type *ct = irq_data_get_chip_type(d);
39	u32 mask = d->mask;
40
41	irq_gc_lock(gc);
42	irq_reg_writel(gc, mask, ct->regs.disable);
43	*ct->mask_cache &= ~mask;
44	irq_gc_unlock(gc);
45}
46
47/**
48 * irq_gc_mask_set_bit - Mask chip via setting bit in mask register
49 * @d: irq_data
50 *
51 * Chip has a single mask register. Values of this register are cached
52 * and protected by gc->lock
53 */
54void irq_gc_mask_set_bit(struct irq_data *d)
55{
56	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
57	struct irq_chip_type *ct = irq_data_get_chip_type(d);
58	u32 mask = d->mask;
59
60	irq_gc_lock(gc);
61	*ct->mask_cache |= mask;
62	irq_reg_writel(gc, *ct->mask_cache, ct->regs.mask);
63	irq_gc_unlock(gc);
64}
65EXPORT_SYMBOL_GPL(irq_gc_mask_set_bit);
66
67/**
68 * irq_gc_mask_clr_bit - Mask chip via clearing bit in mask register
69 * @d: irq_data
70 *
71 * Chip has a single mask register. Values of this register are cached
72 * and protected by gc->lock
73 */
74void irq_gc_mask_clr_bit(struct irq_data *d)
75{
76	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
77	struct irq_chip_type *ct = irq_data_get_chip_type(d);
78	u32 mask = d->mask;
79
80	irq_gc_lock(gc);
81	*ct->mask_cache &= ~mask;
82	irq_reg_writel(gc, *ct->mask_cache, ct->regs.mask);
83	irq_gc_unlock(gc);
84}
85EXPORT_SYMBOL_GPL(irq_gc_mask_clr_bit);
86
87/**
88 * irq_gc_unmask_enable_reg - Unmask chip via enable register
89 * @d: irq_data
90 *
91 * Chip has separate enable/disable registers instead of a single mask
92 * register.
93 */
94void irq_gc_unmask_enable_reg(struct irq_data *d)
95{
96	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
97	struct irq_chip_type *ct = irq_data_get_chip_type(d);
98	u32 mask = d->mask;
99
100	irq_gc_lock(gc);
101	irq_reg_writel(gc, mask, ct->regs.enable);
102	*ct->mask_cache |= mask;
103	irq_gc_unlock(gc);
104}
105
106/**
107 * irq_gc_ack_set_bit - Ack pending interrupt via setting bit
108 * @d: irq_data
109 */
110void irq_gc_ack_set_bit(struct irq_data *d)
111{
112	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
113	struct irq_chip_type *ct = irq_data_get_chip_type(d);
114	u32 mask = d->mask;
115
116	irq_gc_lock(gc);
117	irq_reg_writel(gc, mask, ct->regs.ack);
118	irq_gc_unlock(gc);
119}
120EXPORT_SYMBOL_GPL(irq_gc_ack_set_bit);
121
122/**
123 * irq_gc_ack_clr_bit - Ack pending interrupt via clearing bit
124 * @d: irq_data
125 */
126void irq_gc_ack_clr_bit(struct irq_data *d)
127{
128	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
129	struct irq_chip_type *ct = irq_data_get_chip_type(d);
130	u32 mask = ~d->mask;
131
132	irq_gc_lock(gc);
133	irq_reg_writel(gc, mask, ct->regs.ack);
134	irq_gc_unlock(gc);
135}
136
137/**
138 * irq_gc_mask_disable_reg_and_ack - Mask and ack pending interrupt
139 * @d: irq_data
140 */
141void irq_gc_mask_disable_reg_and_ack(struct irq_data *d)
142{
143	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
144	struct irq_chip_type *ct = irq_data_get_chip_type(d);
145	u32 mask = d->mask;
146
147	irq_gc_lock(gc);
148	irq_reg_writel(gc, mask, ct->regs.mask);
149	irq_reg_writel(gc, mask, ct->regs.ack);
150	irq_gc_unlock(gc);
151}
152
153/**
154 * irq_gc_eoi - EOI interrupt
155 * @d: irq_data
156 */
157void irq_gc_eoi(struct irq_data *d)
158{
159	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
160	struct irq_chip_type *ct = irq_data_get_chip_type(d);
161	u32 mask = d->mask;
162
163	irq_gc_lock(gc);
164	irq_reg_writel(gc, mask, ct->regs.eoi);
165	irq_gc_unlock(gc);
166}
167
168/**
169 * irq_gc_set_wake - Set/clr wake bit for an interrupt
170 * @d:  irq_data
171 * @on: Indicates whether the wake bit should be set or cleared
172 *
173 * For chips where the wake from suspend functionality is not
174 * configured in a separate register and the wakeup active state is
175 * just stored in a bitmask.
176 */
177int irq_gc_set_wake(struct irq_data *d, unsigned int on)
178{
179	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
180	u32 mask = d->mask;
181
182	if (!(mask & gc->wake_enabled))
183		return -EINVAL;
184
185	irq_gc_lock(gc);
186	if (on)
187		gc->wake_active |= mask;
188	else
189		gc->wake_active &= ~mask;
190	irq_gc_unlock(gc);
191	return 0;
192}
193
194static u32 irq_readl_be(void __iomem *addr)
195{
196	return ioread32be(addr);
197}
198
199static void irq_writel_be(u32 val, void __iomem *addr)
200{
201	iowrite32be(val, addr);
202}
203
204static void
205irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
206		      int num_ct, unsigned int irq_base,
207		      void __iomem *reg_base, irq_flow_handler_t handler)
208{
209	raw_spin_lock_init(&gc->lock);
210	gc->num_ct = num_ct;
211	gc->irq_base = irq_base;
212	gc->reg_base = reg_base;
213	gc->chip_types->chip.name = name;
214	gc->chip_types->handler = handler;
215}
216
217/**
218 * irq_alloc_generic_chip - Allocate a generic chip and initialize it
219 * @name:	Name of the irq chip
220 * @num_ct:	Number of irq_chip_type instances associated with this
221 * @irq_base:	Interrupt base nr for this chip
222 * @reg_base:	Register base address (virtual)
223 * @handler:	Default flow handler associated with this chip
224 *
225 * Returns an initialized irq_chip_generic structure. The chip defaults
226 * to the primary (index 0) irq_chip_type and @handler
227 */
228struct irq_chip_generic *
229irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base,
230		       void __iomem *reg_base, irq_flow_handler_t handler)
231{
232	struct irq_chip_generic *gc;
233	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
234
235	gc = kzalloc(sz, GFP_KERNEL);
236	if (gc) {
237		irq_init_generic_chip(gc, name, num_ct, irq_base, reg_base,
238				      handler);
239	}
240	return gc;
241}
242EXPORT_SYMBOL_GPL(irq_alloc_generic_chip);
243
244static void
245irq_gc_init_mask_cache(struct irq_chip_generic *gc, enum irq_gc_flags flags)
246{
247	struct irq_chip_type *ct = gc->chip_types;
248	u32 *mskptr = &gc->mask_cache, mskreg = ct->regs.mask;
249	int i;
250
251	for (i = 0; i < gc->num_ct; i++) {
252		if (flags & IRQ_GC_MASK_CACHE_PER_TYPE) {
253			mskptr = &ct[i].mask_cache_priv;
254			mskreg = ct[i].regs.mask;
255		}
256		ct[i].mask_cache = mskptr;
257		if (flags & IRQ_GC_INIT_MASK_CACHE)
258			*mskptr = irq_reg_readl(gc, mskreg);
259	}
260}
261
262/**
263 * irq_alloc_domain_generic_chip - Allocate generic chips for an irq domain
264 * @d:			irq domain for which to allocate chips
265 * @irqs_per_chip:	Number of interrupts each chip handles
266 * @num_ct:		Number of irq_chip_type instances associated with this
267 * @name:		Name of the irq chip
268 * @handler:		Default flow handler associated with these chips
269 * @clr:		IRQ_* bits to clear in the mapping function
270 * @set:		IRQ_* bits to set in the mapping function
271 * @gcflags:		Generic chip specific setup flags
272 */
273int irq_alloc_domain_generic_chips(struct irq_domain *d, int irqs_per_chip,
274				   int num_ct, const char *name,
275				   irq_flow_handler_t handler,
276				   unsigned int clr, unsigned int set,
277				   enum irq_gc_flags gcflags)
278{
279	struct irq_domain_chip_generic *dgc;
280	struct irq_chip_generic *gc;
281	int numchips, sz, i;
282	unsigned long flags;
283	void *tmp;
284
285	if (d->gc)
286		return -EBUSY;
287
288	numchips = DIV_ROUND_UP(d->revmap_size, irqs_per_chip);
289	if (!numchips)
290		return -EINVAL;
291
292	/* Allocate a pointer, generic chip and chiptypes for each chip */
293	sz = sizeof(*dgc) + numchips * sizeof(gc);
294	sz += numchips * (sizeof(*gc) + num_ct * sizeof(struct irq_chip_type));
295
296	tmp = dgc = kzalloc(sz, GFP_KERNEL);
297	if (!dgc)
298		return -ENOMEM;
299	dgc->irqs_per_chip = irqs_per_chip;
300	dgc->num_chips = numchips;
301	dgc->irq_flags_to_set = set;
302	dgc->irq_flags_to_clear = clr;
303	dgc->gc_flags = gcflags;
304	d->gc = dgc;
305
306	/* Calc pointer to the first generic chip */
307	tmp += sizeof(*dgc) + numchips * sizeof(gc);
308	for (i = 0; i < numchips; i++) {
309		/* Store the pointer to the generic chip */
310		dgc->gc[i] = gc = tmp;
311		irq_init_generic_chip(gc, name, num_ct, i * irqs_per_chip,
312				      NULL, handler);
313
314		gc->domain = d;
315		if (gcflags & IRQ_GC_BE_IO) {
316			gc->reg_readl = &irq_readl_be;
317			gc->reg_writel = &irq_writel_be;
318		}
319
320		raw_spin_lock_irqsave(&gc_lock, flags);
321		list_add_tail(&gc->list, &gc_list);
322		raw_spin_unlock_irqrestore(&gc_lock, flags);
323		/* Calc pointer to the next generic chip */
324		tmp += sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
325	}
326	d->name = name;
327	return 0;
328}
329EXPORT_SYMBOL_GPL(irq_alloc_domain_generic_chips);
330
331/**
332 * irq_get_domain_generic_chip - Get a pointer to the generic chip of a hw_irq
333 * @d:			irq domain pointer
334 * @hw_irq:		Hardware interrupt number
335 */
336struct irq_chip_generic *
337irq_get_domain_generic_chip(struct irq_domain *d, unsigned int hw_irq)
338{
339	struct irq_domain_chip_generic *dgc = d->gc;
340	int idx;
341
342	if (!dgc)
343		return NULL;
344	idx = hw_irq / dgc->irqs_per_chip;
345	if (idx >= dgc->num_chips)
346		return NULL;
347	return dgc->gc[idx];
348}
349EXPORT_SYMBOL_GPL(irq_get_domain_generic_chip);
350
351/*
352 * Separate lockdep class for interrupt chip which can nest irq_desc
353 * lock.
354 */
355static struct lock_class_key irq_nested_lock_class;
356
357/*
358 * irq_map_generic_chip - Map a generic chip for an irq domain
359 */
360int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
361			 irq_hw_number_t hw_irq)
362{
363	struct irq_data *data = irq_get_irq_data(virq);
364	struct irq_domain_chip_generic *dgc = d->gc;
365	struct irq_chip_generic *gc;
366	struct irq_chip_type *ct;
367	struct irq_chip *chip;
368	unsigned long flags;
369	int idx;
370
371	if (!d->gc)
372		return -ENODEV;
373
374	idx = hw_irq / dgc->irqs_per_chip;
375	if (idx >= dgc->num_chips)
376		return -EINVAL;
377	gc = dgc->gc[idx];
378
379	idx = hw_irq % dgc->irqs_per_chip;
380
381	if (test_bit(idx, &gc->unused))
382		return -ENOTSUPP;
383
384	if (test_bit(idx, &gc->installed))
385		return -EBUSY;
386
387	ct = gc->chip_types;
388	chip = &ct->chip;
389
390	/* We only init the cache for the first mapping of a generic chip */
391	if (!gc->installed) {
392		raw_spin_lock_irqsave(&gc->lock, flags);
393		irq_gc_init_mask_cache(gc, dgc->gc_flags);
394		raw_spin_unlock_irqrestore(&gc->lock, flags);
395	}
396
397	/* Mark the interrupt as installed */
398	set_bit(idx, &gc->installed);
399
400	if (dgc->gc_flags & IRQ_GC_INIT_NESTED_LOCK)
401		irq_set_lockdep_class(virq, &irq_nested_lock_class);
402
403	if (chip->irq_calc_mask)
404		chip->irq_calc_mask(data);
405	else
406		data->mask = 1 << idx;
407
408	irq_set_chip_and_handler(virq, chip, ct->handler);
409	irq_set_chip_data(virq, gc);
410	irq_modify_status(virq, dgc->irq_flags_to_clear, dgc->irq_flags_to_set);
411	return 0;
412}
413EXPORT_SYMBOL_GPL(irq_map_generic_chip);
414
415struct irq_domain_ops irq_generic_chip_ops = {
416	.map	= irq_map_generic_chip,
417	.xlate	= irq_domain_xlate_onetwocell,
418};
419EXPORT_SYMBOL_GPL(irq_generic_chip_ops);
420
421/**
422 * irq_setup_generic_chip - Setup a range of interrupts with a generic chip
423 * @gc:		Generic irq chip holding all data
424 * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
425 * @flags:	Flags for initialization
426 * @clr:	IRQ_* bits to clear
427 * @set:	IRQ_* bits to set
428 *
429 * Set up max. 32 interrupts starting from gc->irq_base. Note, this
430 * initializes all interrupts to the primary irq_chip_type and its
431 * associated handler.
432 */
433void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
434			    enum irq_gc_flags flags, unsigned int clr,
435			    unsigned int set)
436{
437	struct irq_chip_type *ct = gc->chip_types;
438	struct irq_chip *chip = &ct->chip;
439	unsigned int i;
440
441	raw_spin_lock(&gc_lock);
442	list_add_tail(&gc->list, &gc_list);
443	raw_spin_unlock(&gc_lock);
444
445	irq_gc_init_mask_cache(gc, flags);
446
447	for (i = gc->irq_base; msk; msk >>= 1, i++) {
448		if (!(msk & 0x01))
449			continue;
450
451		if (flags & IRQ_GC_INIT_NESTED_LOCK)
452			irq_set_lockdep_class(i, &irq_nested_lock_class);
453
454		if (!(flags & IRQ_GC_NO_MASK)) {
455			struct irq_data *d = irq_get_irq_data(i);
456
457			if (chip->irq_calc_mask)
458				chip->irq_calc_mask(d);
459			else
460				d->mask = 1 << (i - gc->irq_base);
461		}
462		irq_set_chip_and_handler(i, chip, ct->handler);
463		irq_set_chip_data(i, gc);
464		irq_modify_status(i, clr, set);
465	}
466	gc->irq_cnt = i - gc->irq_base;
467}
468EXPORT_SYMBOL_GPL(irq_setup_generic_chip);
469
470/**
471 * irq_setup_alt_chip - Switch to alternative chip
472 * @d:		irq_data for this interrupt
473 * @type:	Flow type to be initialized
474 *
475 * Only to be called from chip->irq_set_type() callbacks.
476 */
477int irq_setup_alt_chip(struct irq_data *d, unsigned int type)
478{
479	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
480	struct irq_chip_type *ct = gc->chip_types;
481	unsigned int i;
482
483	for (i = 0; i < gc->num_ct; i++, ct++) {
484		if (ct->type & type) {
485			d->chip = &ct->chip;
486			irq_data_to_desc(d)->handle_irq = ct->handler;
487			return 0;
488		}
489	}
490	return -EINVAL;
491}
492EXPORT_SYMBOL_GPL(irq_setup_alt_chip);
493
494/**
495 * irq_remove_generic_chip - Remove a chip
496 * @gc:		Generic irq chip holding all data
497 * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
498 * @clr:	IRQ_* bits to clear
499 * @set:	IRQ_* bits to set
500 *
501 * Remove up to 32 interrupts starting from gc->irq_base.
502 */
503void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
504			     unsigned int clr, unsigned int set)
505{
506	unsigned int i = gc->irq_base;
507
508	raw_spin_lock(&gc_lock);
509	list_del(&gc->list);
510	raw_spin_unlock(&gc_lock);
511
512	for (; msk; msk >>= 1, i++) {
513		if (!(msk & 0x01))
514			continue;
515
516		/* Remove handler first. That will mask the irq line */
517		irq_set_handler(i, NULL);
518		irq_set_chip(i, &no_irq_chip);
519		irq_set_chip_data(i, NULL);
520		irq_modify_status(i, clr, set);
521	}
522}
523EXPORT_SYMBOL_GPL(irq_remove_generic_chip);
524
525static struct irq_data *irq_gc_get_irq_data(struct irq_chip_generic *gc)
526{
527	unsigned int virq;
528
529	if (!gc->domain)
530		return irq_get_irq_data(gc->irq_base);
531
532	/*
533	 * We don't know which of the irqs has been actually
534	 * installed. Use the first one.
535	 */
536	if (!gc->installed)
537		return NULL;
538
539	virq = irq_find_mapping(gc->domain, gc->irq_base + __ffs(gc->installed));
540	return virq ? irq_get_irq_data(virq) : NULL;
541}
542
543#ifdef CONFIG_PM
544static int irq_gc_suspend(void)
545{
546	struct irq_chip_generic *gc;
547
548	list_for_each_entry(gc, &gc_list, list) {
549		struct irq_chip_type *ct = gc->chip_types;
550
551		if (ct->chip.irq_suspend) {
552			struct irq_data *data = irq_gc_get_irq_data(gc);
553
554			if (data)
555				ct->chip.irq_suspend(data);
556		}
557	}
558	return 0;
559}
560
561static void irq_gc_resume(void)
562{
563	struct irq_chip_generic *gc;
564
565	list_for_each_entry(gc, &gc_list, list) {
566		struct irq_chip_type *ct = gc->chip_types;
567
568		if (ct->chip.irq_resume) {
569			struct irq_data *data = irq_gc_get_irq_data(gc);
570
571			if (data)
572				ct->chip.irq_resume(data);
573		}
574	}
575}
576#else
577#define irq_gc_suspend NULL
578#define irq_gc_resume NULL
579#endif
580
581static void irq_gc_shutdown(void)
582{
583	struct irq_chip_generic *gc;
584
585	list_for_each_entry(gc, &gc_list, list) {
586		struct irq_chip_type *ct = gc->chip_types;
587
588		if (ct->chip.irq_pm_shutdown) {
589			struct irq_data *data = irq_gc_get_irq_data(gc);
590
591			if (data)
592				ct->chip.irq_pm_shutdown(data);
593		}
594	}
595}
596
597static struct syscore_ops irq_gc_syscore_ops = {
598	.suspend = irq_gc_suspend,
599	.resume = irq_gc_resume,
600	.shutdown = irq_gc_shutdown,
601};
602
603static int __init irq_gc_init_ops(void)
604{
605	register_syscore_ops(&irq_gc_syscore_ops);
606	return 0;
607}
608device_initcall(irq_gc_init_ops);
609