2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5 * This file contains the interrupt descriptor management code
7 * Detailed information is available in Documentation/DocBook/genericirq
10 #include <linux/irq.h>
11 #include <linux/slab.h>
12 #include <linux/export.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel_stat.h>
15 #include <linux/radix-tree.h>
16 #include <linux/bitmap.h>
17 #include <linux/irqdomain.h>
19 #include "internals.h"
22 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 static struct lock_class_key irq_desc_lock_class
;
26 #if defined(CONFIG_SMP)
27 static int __init
irq_affinity_setup(char *str
)
29 zalloc_cpumask_var(&irq_default_affinity
, GFP_NOWAIT
);
30 cpulist_parse(str
, irq_default_affinity
);
32 * Set at least the boot cpu. We don't want to end up with
33 * bugreports caused by random comandline masks
35 cpumask_set_cpu(smp_processor_id(), irq_default_affinity
);
38 __setup("irqaffinity=", irq_affinity_setup
);
40 static void __init
init_irq_default_affinity(void)
42 #ifdef CONFIG_CPUMASK_OFFSTACK
43 if (!irq_default_affinity
)
44 zalloc_cpumask_var(&irq_default_affinity
, GFP_NOWAIT
);
46 if (cpumask_empty(irq_default_affinity
))
47 cpumask_setall(irq_default_affinity
);
50 static void __init
init_irq_default_affinity(void)
56 static int alloc_masks(struct irq_desc
*desc
, gfp_t gfp
, int node
)
58 if (!zalloc_cpumask_var_node(&desc
->irq_common_data
.affinity
,
62 #ifdef CONFIG_GENERIC_PENDING_IRQ
63 if (!zalloc_cpumask_var_node(&desc
->pending_mask
, gfp
, node
)) {
64 free_cpumask_var(desc
->irq_common_data
.affinity
);
71 static void desc_smp_init(struct irq_desc
*desc
, int node
,
72 const struct cpumask
*affinity
)
75 affinity
= irq_default_affinity
;
76 cpumask_copy(desc
->irq_common_data
.affinity
, affinity
);
78 #ifdef CONFIG_GENERIC_PENDING_IRQ
79 cpumask_clear(desc
->pending_mask
);
82 desc
->irq_common_data
.node
= node
;
88 alloc_masks(struct irq_desc
*desc
, gfp_t gfp
, int node
) { return 0; }
90 desc_smp_init(struct irq_desc
*desc
, int node
, const struct cpumask
*affinity
) { }
93 static void desc_set_defaults(unsigned int irq
, struct irq_desc
*desc
, int node
,
94 const struct cpumask
*affinity
, struct module
*owner
)
98 desc
->irq_common_data
.handler_data
= NULL
;
99 desc
->irq_common_data
.msi_desc
= NULL
;
101 desc
->irq_data
.common
= &desc
->irq_common_data
;
102 desc
->irq_data
.irq
= irq
;
103 desc
->irq_data
.chip
= &no_irq_chip
;
104 desc
->irq_data
.chip_data
= NULL
;
105 irq_settings_clr_and_set(desc
, ~0, _IRQ_DEFAULT_INIT_FLAGS
);
106 irqd_set(&desc
->irq_data
, IRQD_IRQ_DISABLED
);
107 desc
->handle_irq
= handle_bad_irq
;
110 desc
->irqs_unhandled
= 0;
113 for_each_possible_cpu(cpu
)
114 *per_cpu_ptr(desc
->kstat_irqs
, cpu
) = 0;
115 desc_smp_init(desc
, node
, affinity
);
118 int nr_irqs
= NR_IRQS
;
119 EXPORT_SYMBOL_GPL(nr_irqs
);
121 static DEFINE_MUTEX(sparse_irq_lock
);
122 static DECLARE_BITMAP(allocated_irqs
, IRQ_BITMAP_BITS
);
124 #ifdef CONFIG_SPARSE_IRQ
126 static RADIX_TREE(irq_desc_tree
, GFP_KERNEL
);
128 static void irq_insert_desc(unsigned int irq
, struct irq_desc
*desc
)
130 radix_tree_insert(&irq_desc_tree
, irq
, desc
);
133 struct irq_desc
*irq_to_desc(unsigned int irq
)
135 return radix_tree_lookup(&irq_desc_tree
, irq
);
137 EXPORT_SYMBOL(irq_to_desc
);
139 static void delete_irq_desc(unsigned int irq
)
141 radix_tree_delete(&irq_desc_tree
, irq
);
145 static void free_masks(struct irq_desc
*desc
)
147 #ifdef CONFIG_GENERIC_PENDING_IRQ
148 free_cpumask_var(desc
->pending_mask
);
150 free_cpumask_var(desc
->irq_common_data
.affinity
);
153 static inline void free_masks(struct irq_desc
*desc
) { }
156 void irq_lock_sparse(void)
158 mutex_lock(&sparse_irq_lock
);
161 void irq_unlock_sparse(void)
163 mutex_unlock(&sparse_irq_lock
);
166 static struct irq_desc
*alloc_desc(int irq
, int node
, unsigned int flags
,
167 const struct cpumask
*affinity
,
168 struct module
*owner
)
170 struct irq_desc
*desc
;
171 gfp_t gfp
= GFP_KERNEL
;
173 desc
= kzalloc_node(sizeof(*desc
), gfp
, node
);
176 /* allocate based on nr_cpu_ids */
177 desc
->kstat_irqs
= alloc_percpu(unsigned int);
178 if (!desc
->kstat_irqs
)
181 if (alloc_masks(desc
, gfp
, node
))
184 raw_spin_lock_init(&desc
->lock
);
185 lockdep_set_class(&desc
->lock
, &irq_desc_lock_class
);
186 init_rcu_head(&desc
->rcu
);
188 desc_set_defaults(irq
, desc
, node
, affinity
, owner
);
189 irqd_set(&desc
->irq_data
, flags
);
194 free_percpu(desc
->kstat_irqs
);
200 static void delayed_free_desc(struct rcu_head
*rhp
)
202 struct irq_desc
*desc
= container_of(rhp
, struct irq_desc
, rcu
);
205 free_percpu(desc
->kstat_irqs
);
209 static void free_desc(unsigned int irq
)
211 struct irq_desc
*desc
= irq_to_desc(irq
);
213 unregister_irq_proc(irq
, desc
);
216 * sparse_irq_lock protects also show_interrupts() and
217 * kstat_irq_usr(). Once we deleted the descriptor from the
218 * sparse tree we can free it. Access in proc will fail to
219 * lookup the descriptor.
221 mutex_lock(&sparse_irq_lock
);
222 delete_irq_desc(irq
);
223 mutex_unlock(&sparse_irq_lock
);
226 * We free the descriptor, masks and stat fields via RCU. That
227 * allows demultiplex interrupts to do rcu based management of
228 * the child interrupts.
230 call_rcu(&desc
->rcu
, delayed_free_desc
);
233 static int alloc_descs(unsigned int start
, unsigned int cnt
, int node
,
234 const struct cpumask
*affinity
, struct module
*owner
)
236 const struct cpumask
*mask
= NULL
;
237 struct irq_desc
*desc
;
241 if (affinity
&& cpumask_empty(affinity
))
244 flags
= affinity
? IRQD_AFFINITY_MANAGED
: 0;
246 for (i
= 0; i
< cnt
; i
++) {
248 cpu
= cpumask_next(cpu
, affinity
);
249 if (cpu
>= nr_cpu_ids
)
250 cpu
= cpumask_first(affinity
);
251 node
= cpu_to_node(cpu
);
254 * For single allocations we use the caller provided
255 * mask otherwise we use the mask of the target cpu
257 mask
= cnt
== 1 ? affinity
: cpumask_of(cpu
);
259 desc
= alloc_desc(start
+ i
, node
, flags
, mask
, owner
);
262 mutex_lock(&sparse_irq_lock
);
263 irq_insert_desc(start
+ i
, desc
);
264 mutex_unlock(&sparse_irq_lock
);
269 for (i
--; i
>= 0; i
--)
270 free_desc(start
+ i
);
272 mutex_lock(&sparse_irq_lock
);
273 bitmap_clear(allocated_irqs
, start
, cnt
);
274 mutex_unlock(&sparse_irq_lock
);
278 static int irq_expand_nr_irqs(unsigned int nr
)
280 if (nr
> IRQ_BITMAP_BITS
)
286 int __init
early_irq_init(void)
288 int i
, initcnt
, node
= first_online_node
;
289 struct irq_desc
*desc
;
291 init_irq_default_affinity();
293 /* Let arch update nr_irqs and return the nr of preallocated irqs */
294 initcnt
= arch_probe_nr_irqs();
295 printk(KERN_INFO
"NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS
, nr_irqs
, initcnt
);
297 if (WARN_ON(nr_irqs
> IRQ_BITMAP_BITS
))
298 nr_irqs
= IRQ_BITMAP_BITS
;
300 if (WARN_ON(initcnt
> IRQ_BITMAP_BITS
))
301 initcnt
= IRQ_BITMAP_BITS
;
303 if (initcnt
> nr_irqs
)
306 for (i
= 0; i
< initcnt
; i
++) {
307 desc
= alloc_desc(i
, node
, 0, NULL
, NULL
);
308 set_bit(i
, allocated_irqs
);
309 irq_insert_desc(i
, desc
);
311 return arch_early_irq_init();
314 #else /* !CONFIG_SPARSE_IRQ */
316 struct irq_desc irq_desc
[NR_IRQS
] __cacheline_aligned_in_smp
= {
317 [0 ... NR_IRQS
-1] = {
318 .handle_irq
= handle_bad_irq
,
320 .lock
= __RAW_SPIN_LOCK_UNLOCKED(irq_desc
->lock
),
324 int __init
early_irq_init(void)
326 int count
, i
, node
= first_online_node
;
327 struct irq_desc
*desc
;
329 init_irq_default_affinity();
331 printk(KERN_INFO
"NR_IRQS:%d\n", NR_IRQS
);
334 count
= ARRAY_SIZE(irq_desc
);
336 for (i
= 0; i
< count
; i
++) {
337 desc
[i
].kstat_irqs
= alloc_percpu(unsigned int);
338 alloc_masks(&desc
[i
], GFP_KERNEL
, node
);
339 raw_spin_lock_init(&desc
[i
].lock
);
340 lockdep_set_class(&desc
[i
].lock
, &irq_desc_lock_class
);
341 desc_set_defaults(i
, &desc
[i
], node
, NULL
, NULL
);
343 return arch_early_irq_init();
346 struct irq_desc
*irq_to_desc(unsigned int irq
)
348 return (irq
< NR_IRQS
) ? irq_desc
+ irq
: NULL
;
350 EXPORT_SYMBOL(irq_to_desc
);
352 static void free_desc(unsigned int irq
)
354 struct irq_desc
*desc
= irq_to_desc(irq
);
357 raw_spin_lock_irqsave(&desc
->lock
, flags
);
358 desc_set_defaults(irq
, desc
, irq_desc_get_node(desc
), NULL
, NULL
);
359 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
362 static inline int alloc_descs(unsigned int start
, unsigned int cnt
, int node
,
363 const struct cpumask
*affinity
,
364 struct module
*owner
)
368 for (i
= 0; i
< cnt
; i
++) {
369 struct irq_desc
*desc
= irq_to_desc(start
+ i
);
376 static int irq_expand_nr_irqs(unsigned int nr
)
381 void irq_mark_irq(unsigned int irq
)
383 mutex_lock(&sparse_irq_lock
);
384 bitmap_set(allocated_irqs
, irq
, 1);
385 mutex_unlock(&sparse_irq_lock
);
388 #ifdef CONFIG_GENERIC_IRQ_LEGACY
389 void irq_init_desc(unsigned int irq
)
395 #endif /* !CONFIG_SPARSE_IRQ */
398 * generic_handle_irq - Invoke the handler for a particular irq
399 * @irq: The irq number to handle
402 int generic_handle_irq(unsigned int irq
)
404 struct irq_desc
*desc
= irq_to_desc(irq
);
408 generic_handle_irq_desc(desc
);
411 EXPORT_SYMBOL_GPL(generic_handle_irq
);
413 #ifdef CONFIG_HANDLE_DOMAIN_IRQ
415 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
416 * @domain: The domain where to perform the lookup
417 * @hwirq: The HW irq number to convert to a logical one
418 * @lookup: Whether to perform the domain lookup or not
419 * @regs: Register file coming from the low-level handling code
421 * Returns: 0 on success, or -EINVAL if conversion has failed
423 int __handle_domain_irq(struct irq_domain
*domain
, unsigned int hwirq
,
424 bool lookup
, struct pt_regs
*regs
)
426 struct pt_regs
*old_regs
= set_irq_regs(regs
);
427 unsigned int irq
= hwirq
;
432 #ifdef CONFIG_IRQ_DOMAIN
434 irq
= irq_find_mapping(domain
, hwirq
);
438 * Some hardware gives randomly wrong interrupts. Rather
439 * than crashing, do something sensible.
441 if (unlikely(!irq
|| irq
>= nr_irqs
)) {
445 generic_handle_irq(irq
);
449 set_irq_regs(old_regs
);
454 /* Dynamic interrupt handling */
457 * irq_free_descs - free irq descriptors
458 * @from: Start of descriptor range
459 * @cnt: Number of consecutive irqs to free
461 void irq_free_descs(unsigned int from
, unsigned int cnt
)
465 if (from
>= nr_irqs
|| (from
+ cnt
) > nr_irqs
)
468 for (i
= 0; i
< cnt
; i
++)
471 mutex_lock(&sparse_irq_lock
);
472 bitmap_clear(allocated_irqs
, from
, cnt
);
473 mutex_unlock(&sparse_irq_lock
);
475 EXPORT_SYMBOL_GPL(irq_free_descs
);
478 * irq_alloc_descs - allocate and initialize a range of irq descriptors
479 * @irq: Allocate for specific irq number if irq >= 0
480 * @from: Start the search from this irq number
481 * @cnt: Number of consecutive irqs to allocate.
482 * @node: Preferred node on which the irq descriptor should be allocated
483 * @owner: Owning module (can be NULL)
484 * @affinity: Optional pointer to an affinity mask which hints where the
485 * irq descriptors should be allocated and which default
488 * Returns the first irq number or error code
491 __irq_alloc_descs(int irq
, unsigned int from
, unsigned int cnt
, int node
,
492 struct module
*owner
, const struct cpumask
*affinity
)
505 * For interrupts which are freely allocated the
506 * architecture can force a lower bound to the @from
507 * argument. x86 uses this to exclude the GSI space.
509 from
= arch_dynirq_lower_bound(from
);
512 mutex_lock(&sparse_irq_lock
);
514 start
= bitmap_find_next_zero_area(allocated_irqs
, IRQ_BITMAP_BITS
,
517 if (irq
>=0 && start
!= irq
)
520 if (start
+ cnt
> nr_irqs
) {
521 ret
= irq_expand_nr_irqs(start
+ cnt
);
526 bitmap_set(allocated_irqs
, start
, cnt
);
527 mutex_unlock(&sparse_irq_lock
);
528 return alloc_descs(start
, cnt
, node
, affinity
, owner
);
531 mutex_unlock(&sparse_irq_lock
);
534 EXPORT_SYMBOL_GPL(__irq_alloc_descs
);
536 #ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
538 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
539 * @cnt: number of interrupts to allocate
540 * @node: node on which to allocate
542 * Returns an interrupt number > 0 or 0, if the allocation fails.
544 unsigned int irq_alloc_hwirqs(int cnt
, int node
)
546 int i
, irq
= __irq_alloc_descs(-1, 0, cnt
, node
, NULL
, NULL
);
551 for (i
= irq
; cnt
> 0; i
++, cnt
--) {
552 if (arch_setup_hwirq(i
, node
))
554 irq_clear_status_flags(i
, _IRQ_NOREQUEST
);
559 for (i
--; i
>= irq
; i
--) {
560 irq_set_status_flags(i
, _IRQ_NOREQUEST
| _IRQ_NOPROBE
);
561 arch_teardown_hwirq(i
);
563 irq_free_descs(irq
, cnt
);
566 EXPORT_SYMBOL_GPL(irq_alloc_hwirqs
);
569 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
570 * @from: Free from irq number
571 * @cnt: number of interrupts to free
574 void irq_free_hwirqs(unsigned int from
, int cnt
)
578 for (i
= from
, j
= cnt
; j
> 0; i
++, j
--) {
579 irq_set_status_flags(i
, _IRQ_NOREQUEST
| _IRQ_NOPROBE
);
580 arch_teardown_hwirq(i
);
582 irq_free_descs(from
, cnt
);
584 EXPORT_SYMBOL_GPL(irq_free_hwirqs
);
588 * irq_get_next_irq - get next allocated irq number
589 * @offset: where to start the search
591 * Returns next irq number after offset or nr_irqs if none is found.
593 unsigned int irq_get_next_irq(unsigned int offset
)
595 return find_next_bit(allocated_irqs
, nr_irqs
, offset
);
599 __irq_get_desc_lock(unsigned int irq
, unsigned long *flags
, bool bus
,
602 struct irq_desc
*desc
= irq_to_desc(irq
);
605 if (check
& _IRQ_DESC_CHECK
) {
606 if ((check
& _IRQ_DESC_PERCPU
) &&
607 !irq_settings_is_per_cpu_devid(desc
))
610 if (!(check
& _IRQ_DESC_PERCPU
) &&
611 irq_settings_is_per_cpu_devid(desc
))
617 raw_spin_lock_irqsave(&desc
->lock
, *flags
);
622 void __irq_put_desc_unlock(struct irq_desc
*desc
, unsigned long flags
, bool bus
)
624 raw_spin_unlock_irqrestore(&desc
->lock
, flags
);
626 chip_bus_sync_unlock(desc
);
629 int irq_set_percpu_devid_partition(unsigned int irq
,
630 const struct cpumask
*affinity
)
632 struct irq_desc
*desc
= irq_to_desc(irq
);
637 if (desc
->percpu_enabled
)
640 desc
->percpu_enabled
= kzalloc(sizeof(*desc
->percpu_enabled
), GFP_KERNEL
);
642 if (!desc
->percpu_enabled
)
646 desc
->percpu_affinity
= affinity
;
648 desc
->percpu_affinity
= cpu_possible_mask
;
650 irq_set_percpu_devid_flags(irq
);
654 int irq_set_percpu_devid(unsigned int irq
)
656 return irq_set_percpu_devid_partition(irq
, NULL
);
659 int irq_get_percpu_devid_partition(unsigned int irq
, struct cpumask
*affinity
)
661 struct irq_desc
*desc
= irq_to_desc(irq
);
663 if (!desc
|| !desc
->percpu_enabled
)
667 cpumask_copy(affinity
, desc
->percpu_affinity
);
672 void kstat_incr_irq_this_cpu(unsigned int irq
)
674 kstat_incr_irqs_this_cpu(irq_to_desc(irq
));
678 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
679 * @irq: The interrupt number
680 * @cpu: The cpu number
682 * Returns the sum of interrupt counts on @cpu since boot for
683 * @irq. The caller must ensure that the interrupt is not removed
686 unsigned int kstat_irqs_cpu(unsigned int irq
, int cpu
)
688 struct irq_desc
*desc
= irq_to_desc(irq
);
690 return desc
&& desc
->kstat_irqs
?
691 *per_cpu_ptr(desc
->kstat_irqs
, cpu
) : 0;
695 * kstat_irqs - Get the statistics for an interrupt
696 * @irq: The interrupt number
698 * Returns the sum of interrupt counts on all cpus since boot for
699 * @irq. The caller must ensure that the interrupt is not removed
702 unsigned int kstat_irqs(unsigned int irq
)
704 struct irq_desc
*desc
= irq_to_desc(irq
);
706 unsigned int sum
= 0;
708 if (!desc
|| !desc
->kstat_irqs
)
710 for_each_possible_cpu(cpu
)
711 sum
+= *per_cpu_ptr(desc
->kstat_irqs
, cpu
);
716 * kstat_irqs_usr - Get the statistics for an interrupt
717 * @irq: The interrupt number
719 * Returns the sum of interrupt counts on all cpus since boot for
720 * @irq. Contrary to kstat_irqs() this can be called from any
721 * preemptible context. It's protected against concurrent removal of
722 * an interrupt descriptor when sparse irqs are enabled.
724 unsigned int kstat_irqs_usr(unsigned int irq
)
729 sum
= kstat_irqs(irq
);