irq: update all arches for new irq_desc
[linux-2.6.git] / arch / powerpc / kernel / irq.c
1 /*
2  *  Derived from arch/i386/kernel/irq.c
3  *    Copyright (C) 1992 Linus Torvalds
4  *  Adapted from arch/i386 by Gary Thomas
5  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6  *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
7  *    Copyright (C) 1996-2001 Cort Dougan
8  *  Adapted for Power Macintosh by Paul Mackerras
9  *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License
13  * as published by the Free Software Foundation; either version
14  * 2 of the License, or (at your option) any later version.
15  *
16  * This file contains the code used by various IRQ handling routines:
17  * asking for different IRQ's should be done through these routines
18  * instead of just grabbing them. Thus setups with different IRQ numbers
19  * shouldn't result in any weird surprises, and installing new handlers
20  * should be easier.
21  *
22  * The MPC8xx has an interrupt mask in the SIU.  If a bit is set, the
23  * interrupt is _enabled_.  As expected, IRQ0 is bit 0 in the 32-bit
24  * mask register (of which only 16 are defined), hence the weird shifting
25  * and complement of the cached_irq_mask.  I want to be able to stuff
26  * this right into the SIU SMASK register.
27  * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
28  * to reduce code space and undefined function references.
29  */
30
31 #undef DEBUG
32
33 #include <linux/module.h>
34 #include <linux/threads.h>
35 #include <linux/kernel_stat.h>
36 #include <linux/signal.h>
37 #include <linux/sched.h>
38 #include <linux/ptrace.h>
39 #include <linux/ioport.h>
40 #include <linux/interrupt.h>
41 #include <linux/timex.h>
42 #include <linux/init.h>
43 #include <linux/slab.h>
44 #include <linux/delay.h>
45 #include <linux/irq.h>
46 #include <linux/seq_file.h>
47 #include <linux/cpumask.h>
48 #include <linux/profile.h>
49 #include <linux/bitops.h>
50 #include <linux/list.h>
51 #include <linux/radix-tree.h>
52 #include <linux/mutex.h>
53 #include <linux/bootmem.h>
54 #include <linux/pci.h>
55 #include <linux/debugfs.h>
56
57 #include <asm/uaccess.h>
58 #include <asm/system.h>
59 #include <asm/io.h>
60 #include <asm/pgtable.h>
61 #include <asm/irq.h>
62 #include <asm/cache.h>
63 #include <asm/prom.h>
64 #include <asm/ptrace.h>
65 #include <asm/machdep.h>
66 #include <asm/udbg.h>
67 #ifdef CONFIG_PPC64
68 #include <asm/paca.h>
69 #include <asm/firmware.h>
70 #include <asm/lv1call.h>
71 #endif
72
73 int __irq_offset_value;
74 static int ppc_spurious_interrupts;
75
76 #ifdef CONFIG_PPC32
77 EXPORT_SYMBOL(__irq_offset_value);
78 atomic_t ppc_n_lost_interrupts;
79
80 #ifdef CONFIG_TAU_INT
81 extern int tau_initialized;
82 extern int tau_interrupts(int);
83 #endif
84 #endif /* CONFIG_PPC32 */
85
86 #ifdef CONFIG_PPC64
87 EXPORT_SYMBOL(irq_desc);
88
89 int distribute_irqs = 1;
90
91 static inline notrace unsigned long get_hard_enabled(void)
92 {
93         unsigned long enabled;
94
95         __asm__ __volatile__("lbz %0,%1(13)"
96         : "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
97
98         return enabled;
99 }
100
101 static inline notrace void set_soft_enabled(unsigned long enable)
102 {
103         __asm__ __volatile__("stb %0,%1(13)"
104         : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
105 }
106
107 notrace void raw_local_irq_restore(unsigned long en)
108 {
109         /*
110          * get_paca()->soft_enabled = en;
111          * Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
112          * That was allowed before, and in such a case we do need to take care
113          * that gcc will set soft_enabled directly via r13, not choose to use
114          * an intermediate register, lest we're preempted to a different cpu.
115          */
116         set_soft_enabled(en);
117         if (!en)
118                 return;
119
120         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
121                 /*
122                  * Do we need to disable preemption here?  Not really: in the
123                  * unlikely event that we're preempted to a different cpu in
124                  * between getting r13, loading its lppaca_ptr, and loading
125                  * its any_int, we might call iseries_handle_interrupts without
126                  * an interrupt pending on the new cpu, but that's no disaster,
127                  * is it?  And the business of preempting us off the old cpu
128                  * would itself involve a local_irq_restore which handles the
129                  * interrupt to that cpu.
130                  *
131                  * But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
132                  * to avoid any preemption checking added into get_paca().
133                  */
134                 if (local_paca->lppaca_ptr->int_dword.any_int)
135                         iseries_handle_interrupts();
136         }
137
138         /*
139          * if (get_paca()->hard_enabled) return;
140          * But again we need to take care that gcc gets hard_enabled directly
141          * via r13, not choose to use an intermediate register, lest we're
142          * preempted to a different cpu in between the two instructions.
143          */
144         if (get_hard_enabled())
145                 return;
146
147         /*
148          * Need to hard-enable interrupts here.  Since currently disabled,
149          * no need to take further asm precautions against preemption; but
150          * use local_paca instead of get_paca() to avoid preemption checking.
151          */
152         local_paca->hard_enabled = en;
153         if ((int)mfspr(SPRN_DEC) < 0)
154                 mtspr(SPRN_DEC, 1);
155
156         /*
157          * Force the delivery of pending soft-disabled interrupts on PS3.
158          * Any HV call will have this side effect.
159          */
160         if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
161                 u64 tmp;
162                 lv1_get_version_info(&tmp);
163         }
164
165         __hard_irq_enable();
166 }
167 EXPORT_SYMBOL(raw_local_irq_restore);
168 #endif /* CONFIG_PPC64 */
169
170 int show_interrupts(struct seq_file *p, void *v)
171 {
172         int i = *(loff_t *)v, j;
173         struct irqaction *action;
174         irq_desc_t *desc;
175         unsigned long flags;
176
177         if (i == 0) {
178                 seq_puts(p, "           ");
179                 for_each_online_cpu(j)
180                         seq_printf(p, "CPU%d       ", j);
181                 seq_putc(p, '\n');
182         }
183
184         if (i < NR_IRQS) {
185                 desc = get_irq_desc(i);
186                 spin_lock_irqsave(&desc->lock, flags);
187                 action = desc->action;
188                 if (!action || !action->handler)
189                         goto skip;
190                 seq_printf(p, "%3d: ", i);
191 #ifdef CONFIG_SMP
192                 for_each_online_cpu(j)
193                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
194 #else
195                 seq_printf(p, "%10u ", kstat_irqs(i));
196 #endif /* CONFIG_SMP */
197                 if (desc->chip)
198                         seq_printf(p, " %s ", desc->chip->typename);
199                 else
200                         seq_puts(p, "  None      ");
201                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
202                 seq_printf(p, "    %s", action->name);
203                 for (action = action->next; action; action = action->next)
204                         seq_printf(p, ", %s", action->name);
205                 seq_putc(p, '\n');
206 skip:
207                 spin_unlock_irqrestore(&desc->lock, flags);
208         } else if (i == NR_IRQS) {
209 #if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
210                 if (tau_initialized){
211                         seq_puts(p, "TAU: ");
212                         for_each_online_cpu(j)
213                                 seq_printf(p, "%10u ", tau_interrupts(j));
214                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
215                 }
216 #endif /* CONFIG_PPC32 && CONFIG_TAU_INT*/
217                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
218         }
219         return 0;
220 }
221
222 #ifdef CONFIG_HOTPLUG_CPU
223 void fixup_irqs(cpumask_t map)
224 {
225         unsigned int irq;
226         static int warned;
227
228         for_each_irq(irq) {
229                 cpumask_t mask;
230
231                 if (irq_desc[irq].status & IRQ_PER_CPU)
232                         continue;
233
234                 cpumask_and(&mask, irq_desc[irq].affinity, &map);
235                 if (any_online_cpu(mask) == NR_CPUS) {
236                         printk("Breaking affinity for irq %i\n", irq);
237                         mask = map;
238                 }
239                 if (irq_desc[irq].chip->set_affinity)
240                         irq_desc[irq].chip->set_affinity(irq, &mask);
241                 else if (irq_desc[irq].action && !(warned++))
242                         printk("Cannot set affinity for irq %i\n", irq);
243         }
244
245         local_irq_enable();
246         mdelay(1);
247         local_irq_disable();
248 }
249 #endif
250
251 void do_IRQ(struct pt_regs *regs)
252 {
253         struct pt_regs *old_regs = set_irq_regs(regs);
254         unsigned int irq;
255 #ifdef CONFIG_IRQSTACKS
256         struct thread_info *curtp, *irqtp;
257 #endif
258
259         irq_enter();
260
261 #ifdef CONFIG_DEBUG_STACKOVERFLOW
262         /* Debugging check for stack overflow: is there less than 2KB free? */
263         {
264                 long sp;
265
266                 sp = __get_SP() & (THREAD_SIZE-1);
267
268                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
269                         printk("do_IRQ: stack overflow: %ld\n",
270                                 sp - sizeof(struct thread_info));
271                         dump_stack();
272                 }
273         }
274 #endif
275
276         /*
277          * Every platform is required to implement ppc_md.get_irq.
278          * This function will either return an irq number or NO_IRQ to
279          * indicate there are no more pending.
280          * The value NO_IRQ_IGNORE is for buggy hardware and means that this
281          * IRQ has already been handled. -- Tom
282          */
283         irq = ppc_md.get_irq();
284
285         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
286 #ifdef CONFIG_IRQSTACKS
287                 /* Switch to the irq stack to handle this */
288                 curtp = current_thread_info();
289                 irqtp = hardirq_ctx[smp_processor_id()];
290                 if (curtp != irqtp) {
291                         struct irq_desc *desc = irq_desc + irq;
292                         void *handler = desc->handle_irq;
293                         unsigned long saved_sp_limit = current->thread.ksp_limit;
294                         if (handler == NULL)
295                                 handler = &__do_IRQ;
296                         irqtp->task = curtp->task;
297                         irqtp->flags = 0;
298
299                         /* Copy the softirq bits in preempt_count so that the
300                          * softirq checks work in the hardirq context.
301                          */
302                         irqtp->preempt_count =
303                                 (irqtp->preempt_count & ~SOFTIRQ_MASK) |
304                                 (curtp->preempt_count & SOFTIRQ_MASK);
305
306                         current->thread.ksp_limit = (unsigned long)irqtp +
307                                 _ALIGN_UP(sizeof(struct thread_info), 16);
308                         call_handle_irq(irq, desc, irqtp, handler);
309                         current->thread.ksp_limit = saved_sp_limit;
310                         irqtp->task = NULL;
311
312
313                         /* Set any flag that may have been set on the
314                          * alternate stack
315                          */
316                         if (irqtp->flags)
317                                 set_bits(irqtp->flags, &curtp->flags);
318                 } else
319 #endif
320                         generic_handle_irq(irq);
321         } else if (irq != NO_IRQ_IGNORE)
322                 /* That's not SMP safe ... but who cares ? */
323                 ppc_spurious_interrupts++;
324
325         irq_exit();
326         set_irq_regs(old_regs);
327
328 #ifdef CONFIG_PPC_ISERIES
329         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
330                         get_lppaca()->int_dword.fields.decr_int) {
331                 get_lppaca()->int_dword.fields.decr_int = 0;
332                 /* Signal a fake decrementer interrupt */
333                 timer_interrupt(regs);
334         }
335 #endif
336 }
337
338 void __init init_IRQ(void)
339 {
340         if (ppc_md.init_IRQ)
341                 ppc_md.init_IRQ();
342
343         exc_lvl_ctx_init();
344
345         irq_ctx_init();
346 }
347
348 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
349 struct thread_info   *critirq_ctx[NR_CPUS] __read_mostly;
350 struct thread_info    *dbgirq_ctx[NR_CPUS] __read_mostly;
351 struct thread_info *mcheckirq_ctx[NR_CPUS] __read_mostly;
352
353 void exc_lvl_ctx_init(void)
354 {
355         struct thread_info *tp;
356         int i;
357
358         for_each_possible_cpu(i) {
359                 memset((void *)critirq_ctx[i], 0, THREAD_SIZE);
360                 tp = critirq_ctx[i];
361                 tp->cpu = i;
362                 tp->preempt_count = 0;
363
364 #ifdef CONFIG_BOOKE
365                 memset((void *)dbgirq_ctx[i], 0, THREAD_SIZE);
366                 tp = dbgirq_ctx[i];
367                 tp->cpu = i;
368                 tp->preempt_count = 0;
369
370                 memset((void *)mcheckirq_ctx[i], 0, THREAD_SIZE);
371                 tp = mcheckirq_ctx[i];
372                 tp->cpu = i;
373                 tp->preempt_count = HARDIRQ_OFFSET;
374 #endif
375         }
376 }
377 #endif
378
379 #ifdef CONFIG_IRQSTACKS
380 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
381 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
382
383 void irq_ctx_init(void)
384 {
385         struct thread_info *tp;
386         int i;
387
388         for_each_possible_cpu(i) {
389                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
390                 tp = softirq_ctx[i];
391                 tp->cpu = i;
392                 tp->preempt_count = 0;
393
394                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
395                 tp = hardirq_ctx[i];
396                 tp->cpu = i;
397                 tp->preempt_count = HARDIRQ_OFFSET;
398         }
399 }
400
401 static inline void do_softirq_onstack(void)
402 {
403         struct thread_info *curtp, *irqtp;
404         unsigned long saved_sp_limit = current->thread.ksp_limit;
405
406         curtp = current_thread_info();
407         irqtp = softirq_ctx[smp_processor_id()];
408         irqtp->task = curtp->task;
409         current->thread.ksp_limit = (unsigned long)irqtp +
410                                     _ALIGN_UP(sizeof(struct thread_info), 16);
411         call_do_softirq(irqtp);
412         current->thread.ksp_limit = saved_sp_limit;
413         irqtp->task = NULL;
414 }
415
416 #else
417 #define do_softirq_onstack()    __do_softirq()
418 #endif /* CONFIG_IRQSTACKS */
419
420 void do_softirq(void)
421 {
422         unsigned long flags;
423
424         if (in_interrupt())
425                 return;
426
427         local_irq_save(flags);
428
429         if (local_softirq_pending())
430                 do_softirq_onstack();
431
432         local_irq_restore(flags);
433 }
434
435
436 /*
437  * IRQ controller and virtual interrupts
438  */
439
440 static LIST_HEAD(irq_hosts);
441 static DEFINE_SPINLOCK(irq_big_lock);
442 static unsigned int revmap_trees_allocated;
443 static DEFINE_MUTEX(revmap_trees_mutex);
444 struct irq_map_entry irq_map[NR_IRQS];
445 static unsigned int irq_virq_count = NR_IRQS;
446 static struct irq_host *irq_default_host;
447
448 irq_hw_number_t virq_to_hw(unsigned int virq)
449 {
450         return irq_map[virq].hwirq;
451 }
452 EXPORT_SYMBOL_GPL(virq_to_hw);
453
454 static int default_irq_host_match(struct irq_host *h, struct device_node *np)
455 {
456         return h->of_node != NULL && h->of_node == np;
457 }
458
459 struct irq_host *irq_alloc_host(struct device_node *of_node,
460                                 unsigned int revmap_type,
461                                 unsigned int revmap_arg,
462                                 struct irq_host_ops *ops,
463                                 irq_hw_number_t inval_irq)
464 {
465         struct irq_host *host;
466         unsigned int size = sizeof(struct irq_host);
467         unsigned int i;
468         unsigned int *rmap;
469         unsigned long flags;
470
471         /* Allocate structure and revmap table if using linear mapping */
472         if (revmap_type == IRQ_HOST_MAP_LINEAR)
473                 size += revmap_arg * sizeof(unsigned int);
474         host = zalloc_maybe_bootmem(size, GFP_KERNEL);
475         if (host == NULL)
476                 return NULL;
477
478         /* Fill structure */
479         host->revmap_type = revmap_type;
480         host->inval_irq = inval_irq;
481         host->ops = ops;
482         host->of_node = of_node_get(of_node);
483
484         if (host->ops->match == NULL)
485                 host->ops->match = default_irq_host_match;
486
487         spin_lock_irqsave(&irq_big_lock, flags);
488
489         /* If it's a legacy controller, check for duplicates and
490          * mark it as allocated (we use irq 0 host pointer for that
491          */
492         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
493                 if (irq_map[0].host != NULL) {
494                         spin_unlock_irqrestore(&irq_big_lock, flags);
495                         /* If we are early boot, we can't free the structure,
496                          * too bad...
497                          * this will be fixed once slab is made available early
498                          * instead of the current cruft
499                          */
500                         if (mem_init_done)
501                                 kfree(host);
502                         return NULL;
503                 }
504                 irq_map[0].host = host;
505         }
506
507         list_add(&host->link, &irq_hosts);
508         spin_unlock_irqrestore(&irq_big_lock, flags);
509
510         /* Additional setups per revmap type */
511         switch(revmap_type) {
512         case IRQ_HOST_MAP_LEGACY:
513                 /* 0 is always the invalid number for legacy */
514                 host->inval_irq = 0;
515                 /* setup us as the host for all legacy interrupts */
516                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
517                         irq_map[i].hwirq = i;
518                         smp_wmb();
519                         irq_map[i].host = host;
520                         smp_wmb();
521
522                         /* Clear norequest flags */
523                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
524
525                         /* Legacy flags are left to default at this point,
526                          * one can then use irq_create_mapping() to
527                          * explicitly change them
528                          */
529                         ops->map(host, i, i);
530                 }
531                 break;
532         case IRQ_HOST_MAP_LINEAR:
533                 rmap = (unsigned int *)(host + 1);
534                 for (i = 0; i < revmap_arg; i++)
535                         rmap[i] = NO_IRQ;
536                 host->revmap_data.linear.size = revmap_arg;
537                 smp_wmb();
538                 host->revmap_data.linear.revmap = rmap;
539                 break;
540         default:
541                 break;
542         }
543
544         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
545
546         return host;
547 }
548
549 struct irq_host *irq_find_host(struct device_node *node)
550 {
551         struct irq_host *h, *found = NULL;
552         unsigned long flags;
553
554         /* We might want to match the legacy controller last since
555          * it might potentially be set to match all interrupts in
556          * the absence of a device node. This isn't a problem so far
557          * yet though...
558          */
559         spin_lock_irqsave(&irq_big_lock, flags);
560         list_for_each_entry(h, &irq_hosts, link)
561                 if (h->ops->match(h, node)) {
562                         found = h;
563                         break;
564                 }
565         spin_unlock_irqrestore(&irq_big_lock, flags);
566         return found;
567 }
568 EXPORT_SYMBOL_GPL(irq_find_host);
569
570 void irq_set_default_host(struct irq_host *host)
571 {
572         pr_debug("irq: Default host set to @0x%p\n", host);
573
574         irq_default_host = host;
575 }
576
577 void irq_set_virq_count(unsigned int count)
578 {
579         pr_debug("irq: Trying to set virq count to %d\n", count);
580
581         BUG_ON(count < NUM_ISA_INTERRUPTS);
582         if (count < NR_IRQS)
583                 irq_virq_count = count;
584 }
585
586 static int irq_setup_virq(struct irq_host *host, unsigned int virq,
587                             irq_hw_number_t hwirq)
588 {
589         /* Clear IRQ_NOREQUEST flag */
590         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
591
592         /* map it */
593         smp_wmb();
594         irq_map[virq].hwirq = hwirq;
595         smp_mb();
596
597         if (host->ops->map(host, virq, hwirq)) {
598                 pr_debug("irq: -> mapping failed, freeing\n");
599                 irq_free_virt(virq, 1);
600                 return -1;
601         }
602
603         return 0;
604 }
605
606 unsigned int irq_create_direct_mapping(struct irq_host *host)
607 {
608         unsigned int virq;
609
610         if (host == NULL)
611                 host = irq_default_host;
612
613         BUG_ON(host == NULL);
614         WARN_ON(host->revmap_type != IRQ_HOST_MAP_NOMAP);
615
616         virq = irq_alloc_virt(host, 1, 0);
617         if (virq == NO_IRQ) {
618                 pr_debug("irq: create_direct virq allocation failed\n");
619                 return NO_IRQ;
620         }
621
622         pr_debug("irq: create_direct obtained virq %d\n", virq);
623
624         if (irq_setup_virq(host, virq, virq))
625                 return NO_IRQ;
626
627         return virq;
628 }
629
630 unsigned int irq_create_mapping(struct irq_host *host,
631                                 irq_hw_number_t hwirq)
632 {
633         unsigned int virq, hint;
634
635         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
636
637         /* Look for default host if nececssary */
638         if (host == NULL)
639                 host = irq_default_host;
640         if (host == NULL) {
641                 printk(KERN_WARNING "irq_create_mapping called for"
642                        " NULL host, hwirq=%lx\n", hwirq);
643                 WARN_ON(1);
644                 return NO_IRQ;
645         }
646         pr_debug("irq: -> using host @%p\n", host);
647
648         /* Check if mapping already exist, if it does, call
649          * host->ops->map() to update the flags
650          */
651         virq = irq_find_mapping(host, hwirq);
652         if (virq != NO_IRQ) {
653                 if (host->ops->remap)
654                         host->ops->remap(host, virq, hwirq);
655                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
656                 return virq;
657         }
658
659         /* Get a virtual interrupt number */
660         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
661                 /* Handle legacy */
662                 virq = (unsigned int)hwirq;
663                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
664                         return NO_IRQ;
665                 return virq;
666         } else {
667                 /* Allocate a virtual interrupt number */
668                 hint = hwirq % irq_virq_count;
669                 virq = irq_alloc_virt(host, 1, hint);
670                 if (virq == NO_IRQ) {
671                         pr_debug("irq: -> virq allocation failed\n");
672                         return NO_IRQ;
673                 }
674         }
675         pr_debug("irq: -> obtained virq %d\n", virq);
676
677         if (irq_setup_virq(host, virq, hwirq))
678                 return NO_IRQ;
679
680         return virq;
681 }
682 EXPORT_SYMBOL_GPL(irq_create_mapping);
683
684 unsigned int irq_create_of_mapping(struct device_node *controller,
685                                    u32 *intspec, unsigned int intsize)
686 {
687         struct irq_host *host;
688         irq_hw_number_t hwirq;
689         unsigned int type = IRQ_TYPE_NONE;
690         unsigned int virq;
691
692         if (controller == NULL)
693                 host = irq_default_host;
694         else
695                 host = irq_find_host(controller);
696         if (host == NULL) {
697                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
698                        controller->full_name);
699                 return NO_IRQ;
700         }
701
702         /* If host has no translation, then we assume interrupt line */
703         if (host->ops->xlate == NULL)
704                 hwirq = intspec[0];
705         else {
706                 if (host->ops->xlate(host, controller, intspec, intsize,
707                                      &hwirq, &type))
708                         return NO_IRQ;
709         }
710
711         /* Create mapping */
712         virq = irq_create_mapping(host, hwirq);
713         if (virq == NO_IRQ)
714                 return virq;
715
716         /* Set type if specified and different than the current one */
717         if (type != IRQ_TYPE_NONE &&
718             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
719                 set_irq_type(virq, type);
720         return virq;
721 }
722 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
723
724 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
725 {
726         struct of_irq oirq;
727
728         if (of_irq_map_one(dev, index, &oirq))
729                 return NO_IRQ;
730
731         return irq_create_of_mapping(oirq.controller, oirq.specifier,
732                                      oirq.size);
733 }
734 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
735
736 void irq_dispose_mapping(unsigned int virq)
737 {
738         struct irq_host *host;
739         irq_hw_number_t hwirq;
740
741         if (virq == NO_IRQ)
742                 return;
743
744         host = irq_map[virq].host;
745         WARN_ON (host == NULL);
746         if (host == NULL)
747                 return;
748
749         /* Never unmap legacy interrupts */
750         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
751                 return;
752
753         /* remove chip and handler */
754         set_irq_chip_and_handler(virq, NULL, NULL);
755
756         /* Make sure it's completed */
757         synchronize_irq(virq);
758
759         /* Tell the PIC about it */
760         if (host->ops->unmap)
761                 host->ops->unmap(host, virq);
762         smp_mb();
763
764         /* Clear reverse map */
765         hwirq = irq_map[virq].hwirq;
766         switch(host->revmap_type) {
767         case IRQ_HOST_MAP_LINEAR:
768                 if (hwirq < host->revmap_data.linear.size)
769                         host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
770                 break;
771         case IRQ_HOST_MAP_TREE:
772                 /*
773                  * Check if radix tree allocated yet, if not then nothing to
774                  * remove.
775                  */
776                 smp_rmb();
777                 if (revmap_trees_allocated < 1)
778                         break;
779                 mutex_lock(&revmap_trees_mutex);
780                 radix_tree_delete(&host->revmap_data.tree, hwirq);
781                 mutex_unlock(&revmap_trees_mutex);
782                 break;
783         }
784
785         /* Destroy map */
786         smp_mb();
787         irq_map[virq].hwirq = host->inval_irq;
788
789         /* Set some flags */
790         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
791
792         /* Free it */
793         irq_free_virt(virq, 1);
794 }
795 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
796
797 unsigned int irq_find_mapping(struct irq_host *host,
798                               irq_hw_number_t hwirq)
799 {
800         unsigned int i;
801         unsigned int hint = hwirq % irq_virq_count;
802
803         /* Look for default host if nececssary */
804         if (host == NULL)
805                 host = irq_default_host;
806         if (host == NULL)
807                 return NO_IRQ;
808
809         /* legacy -> bail early */
810         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
811                 return hwirq;
812
813         /* Slow path does a linear search of the map */
814         if (hint < NUM_ISA_INTERRUPTS)
815                 hint = NUM_ISA_INTERRUPTS;
816         i = hint;
817         do  {
818                 if (irq_map[i].host == host &&
819                     irq_map[i].hwirq == hwirq)
820                         return i;
821                 i++;
822                 if (i >= irq_virq_count)
823                         i = NUM_ISA_INTERRUPTS;
824         } while(i != hint);
825         return NO_IRQ;
826 }
827 EXPORT_SYMBOL_GPL(irq_find_mapping);
828
829
830 unsigned int irq_radix_revmap_lookup(struct irq_host *host,
831                                      irq_hw_number_t hwirq)
832 {
833         struct irq_map_entry *ptr;
834         unsigned int virq;
835
836         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
837
838         /*
839          * Check if the radix tree exists and has bee initialized.
840          * If not, we fallback to slow mode
841          */
842         if (revmap_trees_allocated < 2)
843                 return irq_find_mapping(host, hwirq);
844
845         /* Now try to resolve */
846         /*
847          * No rcu_read_lock(ing) needed, the ptr returned can't go under us
848          * as it's referencing an entry in the static irq_map table.
849          */
850         ptr = radix_tree_lookup(&host->revmap_data.tree, hwirq);
851
852         /*
853          * If found in radix tree, then fine.
854          * Else fallback to linear lookup - this should not happen in practice
855          * as it means that we failed to insert the node in the radix tree.
856          */
857         if (ptr)
858                 virq = ptr - irq_map;
859         else
860                 virq = irq_find_mapping(host, hwirq);
861
862         return virq;
863 }
864
865 void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
866                              irq_hw_number_t hwirq)
867 {
868
869         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
870
871         /*
872          * Check if the radix tree exists yet.
873          * If not, then the irq will be inserted into the tree when it gets
874          * initialized.
875          */
876         smp_rmb();
877         if (revmap_trees_allocated < 1)
878                 return;
879
880         if (virq != NO_IRQ) {
881                 mutex_lock(&revmap_trees_mutex);
882                 radix_tree_insert(&host->revmap_data.tree, hwirq,
883                                   &irq_map[virq]);
884                 mutex_unlock(&revmap_trees_mutex);
885         }
886 }
887
888 unsigned int irq_linear_revmap(struct irq_host *host,
889                                irq_hw_number_t hwirq)
890 {
891         unsigned int *revmap;
892
893         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
894
895         /* Check revmap bounds */
896         if (unlikely(hwirq >= host->revmap_data.linear.size))
897                 return irq_find_mapping(host, hwirq);
898
899         /* Check if revmap was allocated */
900         revmap = host->revmap_data.linear.revmap;
901         if (unlikely(revmap == NULL))
902                 return irq_find_mapping(host, hwirq);
903
904         /* Fill up revmap with slow path if no mapping found */
905         if (unlikely(revmap[hwirq] == NO_IRQ))
906                 revmap[hwirq] = irq_find_mapping(host, hwirq);
907
908         return revmap[hwirq];
909 }
910
911 unsigned int irq_alloc_virt(struct irq_host *host,
912                             unsigned int count,
913                             unsigned int hint)
914 {
915         unsigned long flags;
916         unsigned int i, j, found = NO_IRQ;
917
918         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
919                 return NO_IRQ;
920
921         spin_lock_irqsave(&irq_big_lock, flags);
922
923         /* Use hint for 1 interrupt if any */
924         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
925             hint < irq_virq_count && irq_map[hint].host == NULL) {
926                 found = hint;
927                 goto hint_found;
928         }
929
930         /* Look for count consecutive numbers in the allocatable
931          * (non-legacy) space
932          */
933         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
934                 if (irq_map[i].host != NULL)
935                         j = 0;
936                 else
937                         j++;
938
939                 if (j == count) {
940                         found = i - count + 1;
941                         break;
942                 }
943         }
944         if (found == NO_IRQ) {
945                 spin_unlock_irqrestore(&irq_big_lock, flags);
946                 return NO_IRQ;
947         }
948  hint_found:
949         for (i = found; i < (found + count); i++) {
950                 irq_map[i].hwirq = host->inval_irq;
951                 smp_wmb();
952                 irq_map[i].host = host;
953         }
954         spin_unlock_irqrestore(&irq_big_lock, flags);
955         return found;
956 }
957
958 void irq_free_virt(unsigned int virq, unsigned int count)
959 {
960         unsigned long flags;
961         unsigned int i;
962
963         WARN_ON (virq < NUM_ISA_INTERRUPTS);
964         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
965
966         spin_lock_irqsave(&irq_big_lock, flags);
967         for (i = virq; i < (virq + count); i++) {
968                 struct irq_host *host;
969
970                 if (i < NUM_ISA_INTERRUPTS ||
971                     (virq + count) > irq_virq_count)
972                         continue;
973
974                 host = irq_map[i].host;
975                 irq_map[i].hwirq = host->inval_irq;
976                 smp_wmb();
977                 irq_map[i].host = NULL;
978         }
979         spin_unlock_irqrestore(&irq_big_lock, flags);
980 }
981
982 void irq_early_init(void)
983 {
984         unsigned int i;
985
986         for (i = 0; i < NR_IRQS; i++)
987                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
988 }
989
990 /* We need to create the radix trees late */
991 static int irq_late_init(void)
992 {
993         struct irq_host *h;
994         unsigned int i;
995
996         /*
997          * No mutual exclusion with respect to accessors of the tree is needed
998          * here as the synchronization is done via the state variable
999          * revmap_trees_allocated.
1000          */
1001         list_for_each_entry(h, &irq_hosts, link) {
1002                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
1003                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_KERNEL);
1004         }
1005
1006         /*
1007          * Make sure the radix trees inits are visible before setting
1008          * the flag
1009          */
1010         smp_wmb();
1011         revmap_trees_allocated = 1;
1012
1013         /*
1014          * Insert the reverse mapping for those interrupts already present
1015          * in irq_map[].
1016          */
1017         mutex_lock(&revmap_trees_mutex);
1018         for (i = 0; i < irq_virq_count; i++) {
1019                 if (irq_map[i].host &&
1020                     (irq_map[i].host->revmap_type == IRQ_HOST_MAP_TREE))
1021                         radix_tree_insert(&irq_map[i].host->revmap_data.tree,
1022                                           irq_map[i].hwirq, &irq_map[i]);
1023         }
1024         mutex_unlock(&revmap_trees_mutex);
1025
1026         /*
1027          * Make sure the radix trees insertions are visible before setting
1028          * the flag
1029          */
1030         smp_wmb();
1031         revmap_trees_allocated = 2;
1032
1033         return 0;
1034 }
1035 arch_initcall(irq_late_init);
1036
1037 #ifdef CONFIG_VIRQ_DEBUG
1038 static int virq_debug_show(struct seq_file *m, void *private)
1039 {
1040         unsigned long flags;
1041         irq_desc_t *desc;
1042         const char *p;
1043         char none[] = "none";
1044         int i;
1045
1046         seq_printf(m, "%-5s  %-7s  %-15s  %s\n", "virq", "hwirq",
1047                       "chip name", "host name");
1048
1049         for (i = 1; i < NR_IRQS; i++) {
1050                 desc = get_irq_desc(i);
1051                 spin_lock_irqsave(&desc->lock, flags);
1052
1053                 if (desc->action && desc->action->handler) {
1054                         seq_printf(m, "%5d  ", i);
1055                         seq_printf(m, "0x%05lx  ", virq_to_hw(i));
1056
1057                         if (desc->chip && desc->chip->typename)
1058                                 p = desc->chip->typename;
1059                         else
1060                                 p = none;
1061                         seq_printf(m, "%-15s  ", p);
1062
1063                         if (irq_map[i].host && irq_map[i].host->of_node)
1064                                 p = irq_map[i].host->of_node->full_name;
1065                         else
1066                                 p = none;
1067                         seq_printf(m, "%s\n", p);
1068                 }
1069
1070                 spin_unlock_irqrestore(&desc->lock, flags);
1071         }
1072
1073         return 0;
1074 }
1075
1076 static int virq_debug_open(struct inode *inode, struct file *file)
1077 {
1078         return single_open(file, virq_debug_show, inode->i_private);
1079 }
1080
1081 static const struct file_operations virq_debug_fops = {
1082         .open = virq_debug_open,
1083         .read = seq_read,
1084         .llseek = seq_lseek,
1085         .release = single_release,
1086 };
1087
1088 static int __init irq_debugfs_init(void)
1089 {
1090         if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
1091                                  NULL, &virq_debug_fops) == NULL)
1092                 return -ENOMEM;
1093
1094         return 0;
1095 }
1096 __initcall(irq_debugfs_init);
1097 #endif /* CONFIG_VIRQ_DEBUG */
1098
1099 #ifdef CONFIG_PPC64
1100 static int __init setup_noirqdistrib(char *str)
1101 {
1102         distribute_irqs = 0;
1103         return 1;
1104 }
1105
1106 __setup("noirqdistrib", setup_noirqdistrib);
1107 #endif /* CONFIG_PPC64 */