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 void __init init_irq_default_affinity(void)
29 alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
30 cpumask_setall(irq_default_affinity);
33 static void __init init_irq_default_affinity(void)
39 static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
41 if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
44 #ifdef CONFIG_GENERIC_PENDING_IRQ
45 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
46 free_cpumask_var(desc->irq_data.affinity);
53 static void desc_smp_init(struct irq_desc *desc, int node)
55 cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
56 #ifdef CONFIG_GENERIC_PENDING_IRQ
57 cpumask_clear(desc->pending_mask);
60 desc->irq_common_data.node = node;
66 alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
67 static inline void desc_smp_init(struct irq_desc *desc, int node) { }
70 static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
75 desc->irq_common_data.handler_data = NULL;
77 desc->irq_data.common = &desc->irq_common_data;
78 desc->irq_data.irq = irq;
79 desc->irq_data.chip = &no_irq_chip;
80 desc->irq_data.chip_data = NULL;
81 desc->irq_data.msi_desc = NULL;
82 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
83 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
84 desc->handle_irq = handle_bad_irq;
87 desc->irqs_unhandled = 0;
90 for_each_possible_cpu(cpu)
91 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
92 desc_smp_init(desc, node);
95 int nr_irqs = NR_IRQS;
96 EXPORT_SYMBOL_GPL(nr_irqs);
98 static DEFINE_MUTEX(sparse_irq_lock);
99 static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
101 #ifdef CONFIG_SPARSE_IRQ
103 static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
105 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
107 radix_tree_insert(&irq_desc_tree, irq, desc);
110 struct irq_desc *irq_to_desc(unsigned int irq)
112 return radix_tree_lookup(&irq_desc_tree, irq);
114 EXPORT_SYMBOL(irq_to_desc);
116 static void delete_irq_desc(unsigned int irq)
118 radix_tree_delete(&irq_desc_tree, irq);
122 static void free_masks(struct irq_desc *desc)
124 #ifdef CONFIG_GENERIC_PENDING_IRQ
125 free_cpumask_var(desc->pending_mask);
127 free_cpumask_var(desc->irq_data.affinity);
130 static inline void free_masks(struct irq_desc *desc) { }
133 void irq_lock_sparse(void)
135 mutex_lock(&sparse_irq_lock);
138 void irq_unlock_sparse(void)
140 mutex_unlock(&sparse_irq_lock);
143 static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
145 struct irq_desc *desc;
146 gfp_t gfp = GFP_KERNEL;
148 desc = kzalloc_node(sizeof(*desc), gfp, node);
151 /* allocate based on nr_cpu_ids */
152 desc->kstat_irqs = alloc_percpu(unsigned int);
153 if (!desc->kstat_irqs)
156 if (alloc_masks(desc, gfp, node))
159 raw_spin_lock_init(&desc->lock);
160 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
162 desc_set_defaults(irq, desc, node, owner);
167 free_percpu(desc->kstat_irqs);
173 static void free_desc(unsigned int irq)
175 struct irq_desc *desc = irq_to_desc(irq);
177 unregister_irq_proc(irq, desc);
180 * sparse_irq_lock protects also show_interrupts() and
181 * kstat_irq_usr(). Once we deleted the descriptor from the
182 * sparse tree we can free it. Access in proc will fail to
183 * lookup the descriptor.
185 mutex_lock(&sparse_irq_lock);
186 delete_irq_desc(irq);
187 mutex_unlock(&sparse_irq_lock);
190 free_percpu(desc->kstat_irqs);
194 static int alloc_descs(unsigned int start, unsigned int cnt, int node,
195 struct module *owner)
197 struct irq_desc *desc;
200 for (i = 0; i < cnt; i++) {
201 desc = alloc_desc(start + i, node, owner);
204 mutex_lock(&sparse_irq_lock);
205 irq_insert_desc(start + i, desc);
206 mutex_unlock(&sparse_irq_lock);
211 for (i--; i >= 0; i--)
212 free_desc(start + i);
214 mutex_lock(&sparse_irq_lock);
215 bitmap_clear(allocated_irqs, start, cnt);
216 mutex_unlock(&sparse_irq_lock);
220 static int irq_expand_nr_irqs(unsigned int nr)
222 if (nr > IRQ_BITMAP_BITS)
228 int __init early_irq_init(void)
230 int i, initcnt, node = first_online_node;
231 struct irq_desc *desc;
233 init_irq_default_affinity();
235 /* Let arch update nr_irqs and return the nr of preallocated irqs */
236 initcnt = arch_probe_nr_irqs();
237 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
239 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
240 nr_irqs = IRQ_BITMAP_BITS;
242 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
243 initcnt = IRQ_BITMAP_BITS;
245 if (initcnt > nr_irqs)
248 for (i = 0; i < initcnt; i++) {
249 desc = alloc_desc(i, node, NULL);
250 set_bit(i, allocated_irqs);
251 irq_insert_desc(i, desc);
253 return arch_early_irq_init();
256 #else /* !CONFIG_SPARSE_IRQ */
258 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
259 [0 ... NR_IRQS-1] = {
260 .handle_irq = handle_bad_irq,
262 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
266 int __init early_irq_init(void)
268 int count, i, node = first_online_node;
269 struct irq_desc *desc;
271 init_irq_default_affinity();
273 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
276 count = ARRAY_SIZE(irq_desc);
278 for (i = 0; i < count; i++) {
279 desc[i].kstat_irqs = alloc_percpu(unsigned int);
280 alloc_masks(&desc[i], GFP_KERNEL, node);
281 raw_spin_lock_init(&desc[i].lock);
282 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
283 desc_set_defaults(i, &desc[i], node, NULL);
285 return arch_early_irq_init();
288 struct irq_desc *irq_to_desc(unsigned int irq)
290 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
292 EXPORT_SYMBOL(irq_to_desc);
294 static void free_desc(unsigned int irq)
296 struct irq_desc *desc = irq_to_desc(irq);
299 raw_spin_lock_irqsave(&desc->lock, flags);
300 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL);
301 raw_spin_unlock_irqrestore(&desc->lock, flags);
304 static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
305 struct module *owner)
309 for (i = 0; i < cnt; i++) {
310 struct irq_desc *desc = irq_to_desc(start + i);
317 static int irq_expand_nr_irqs(unsigned int nr)
322 void irq_mark_irq(unsigned int irq)
324 mutex_lock(&sparse_irq_lock);
325 bitmap_set(allocated_irqs, irq, 1);
326 mutex_unlock(&sparse_irq_lock);
329 #ifdef CONFIG_GENERIC_IRQ_LEGACY
330 void irq_init_desc(unsigned int irq)
336 #endif /* !CONFIG_SPARSE_IRQ */
339 * generic_handle_irq - Invoke the handler for a particular irq
340 * @irq: The irq number to handle
343 int generic_handle_irq(unsigned int irq)
345 struct irq_desc *desc = irq_to_desc(irq);
349 generic_handle_irq_desc(irq, desc);
352 EXPORT_SYMBOL_GPL(generic_handle_irq);
354 #ifdef CONFIG_HANDLE_DOMAIN_IRQ
356 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
357 * @domain: The domain where to perform the lookup
358 * @hwirq: The HW irq number to convert to a logical one
359 * @lookup: Whether to perform the domain lookup or not
360 * @regs: Register file coming from the low-level handling code
362 * Returns: 0 on success, or -EINVAL if conversion has failed
364 int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
365 bool lookup, struct pt_regs *regs)
367 struct pt_regs *old_regs = set_irq_regs(regs);
368 unsigned int irq = hwirq;
373 #ifdef CONFIG_IRQ_DOMAIN
375 irq = irq_find_mapping(domain, hwirq);
379 * Some hardware gives randomly wrong interrupts. Rather
380 * than crashing, do something sensible.
382 if (unlikely(!irq || irq >= nr_irqs)) {
386 generic_handle_irq(irq);
390 set_irq_regs(old_regs);
395 /* Dynamic interrupt handling */
398 * irq_free_descs - free irq descriptors
399 * @from: Start of descriptor range
400 * @cnt: Number of consecutive irqs to free
402 void irq_free_descs(unsigned int from, unsigned int cnt)
406 if (from >= nr_irqs || (from + cnt) > nr_irqs)
409 for (i = 0; i < cnt; i++)
412 mutex_lock(&sparse_irq_lock);
413 bitmap_clear(allocated_irqs, from, cnt);
414 mutex_unlock(&sparse_irq_lock);
416 EXPORT_SYMBOL_GPL(irq_free_descs);
419 * irq_alloc_descs - allocate and initialize a range of irq descriptors
420 * @irq: Allocate for specific irq number if irq >= 0
421 * @from: Start the search from this irq number
422 * @cnt: Number of consecutive irqs to allocate.
423 * @node: Preferred node on which the irq descriptor should be allocated
424 * @owner: Owning module (can be NULL)
426 * Returns the first irq number or error code
429 __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
430 struct module *owner)
443 * For interrupts which are freely allocated the
444 * architecture can force a lower bound to the @from
445 * argument. x86 uses this to exclude the GSI space.
447 from = arch_dynirq_lower_bound(from);
450 mutex_lock(&sparse_irq_lock);
452 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
455 if (irq >=0 && start != irq)
458 if (start + cnt > nr_irqs) {
459 ret = irq_expand_nr_irqs(start + cnt);
464 bitmap_set(allocated_irqs, start, cnt);
465 mutex_unlock(&sparse_irq_lock);
466 return alloc_descs(start, cnt, node, owner);
469 mutex_unlock(&sparse_irq_lock);
472 EXPORT_SYMBOL_GPL(__irq_alloc_descs);
474 #ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
476 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
477 * @cnt: number of interrupts to allocate
478 * @node: node on which to allocate
480 * Returns an interrupt number > 0 or 0, if the allocation fails.
482 unsigned int irq_alloc_hwirqs(int cnt, int node)
484 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL);
489 for (i = irq; cnt > 0; i++, cnt--) {
490 if (arch_setup_hwirq(i, node))
492 irq_clear_status_flags(i, _IRQ_NOREQUEST);
497 for (i--; i >= irq; i--) {
498 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
499 arch_teardown_hwirq(i);
501 irq_free_descs(irq, cnt);
504 EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
507 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
508 * @from: Free from irq number
509 * @cnt: number of interrupts to free
512 void irq_free_hwirqs(unsigned int from, int cnt)
516 for (i = from, j = cnt; j > 0; i++, j--) {
517 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
518 arch_teardown_hwirq(i);
520 irq_free_descs(from, cnt);
522 EXPORT_SYMBOL_GPL(irq_free_hwirqs);
526 * irq_get_next_irq - get next allocated irq number
527 * @offset: where to start the search
529 * Returns next irq number after offset or nr_irqs if none is found.
531 unsigned int irq_get_next_irq(unsigned int offset)
533 return find_next_bit(allocated_irqs, nr_irqs, offset);
537 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
540 struct irq_desc *desc = irq_to_desc(irq);
543 if (check & _IRQ_DESC_CHECK) {
544 if ((check & _IRQ_DESC_PERCPU) &&
545 !irq_settings_is_per_cpu_devid(desc))
548 if (!(check & _IRQ_DESC_PERCPU) &&
549 irq_settings_is_per_cpu_devid(desc))
555 raw_spin_lock_irqsave(&desc->lock, *flags);
560 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
562 raw_spin_unlock_irqrestore(&desc->lock, flags);
564 chip_bus_sync_unlock(desc);
567 int irq_set_percpu_devid(unsigned int irq)
569 struct irq_desc *desc = irq_to_desc(irq);
574 if (desc->percpu_enabled)
577 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
579 if (!desc->percpu_enabled)
582 irq_set_percpu_devid_flags(irq);
586 void kstat_incr_irq_this_cpu(unsigned int irq)
588 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
592 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
593 * @irq: The interrupt number
594 * @cpu: The cpu number
596 * Returns the sum of interrupt counts on @cpu since boot for
597 * @irq. The caller must ensure that the interrupt is not removed
600 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
602 struct irq_desc *desc = irq_to_desc(irq);
604 return desc && desc->kstat_irqs ?
605 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
609 * kstat_irqs - Get the statistics for an interrupt
610 * @irq: The interrupt number
612 * Returns the sum of interrupt counts on all cpus since boot for
613 * @irq. The caller must ensure that the interrupt is not removed
616 unsigned int kstat_irqs(unsigned int irq)
618 struct irq_desc *desc = irq_to_desc(irq);
620 unsigned int sum = 0;
622 if (!desc || !desc->kstat_irqs)
624 for_each_possible_cpu(cpu)
625 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
630 * kstat_irqs_usr - Get the statistics for an interrupt
631 * @irq: The interrupt number
633 * Returns the sum of interrupt counts on all cpus since boot for
634 * @irq. Contrary to kstat_irqs() this can be called from any
635 * preemptible context. It's protected against concurrent removal of
636 * an interrupt descriptor when sparse irqs are enabled.
638 unsigned int kstat_irqs_usr(unsigned int irq)
643 sum = kstat_irqs(irq);