Merge tag '8139cp-20060912-00' of git://electric-eye.fr.zoreil.com/home/romieu/linux...
[linux-2.6] / 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  *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; either version
15  * 2 of the License, or (at your option) any later version.
16  *
17  * This file contains the code used by various IRQ handling routines:
18  * asking for different IRQ's should be done through these routines
19  * instead of just grabbing them. Thus setups with different IRQ numbers
20  * shouldn't result in any weird surprises, and installing new handlers
21  * should be easier.
22  *
23  * The MPC8xx has an interrupt mask in the SIU.  If a bit is set, the
24  * interrupt is _enabled_.  As expected, IRQ0 is bit 0 in the 32-bit
25  * mask register (of which only 16 are defined), hence the weird shifting
26  * and complement of the cached_irq_mask.  I want to be able to stuff
27  * this right into the SIU SMASK register.
28  * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
29  * to reduce code space and undefined function references.
30  */
31
32 #undef DEBUG
33
34 #include <linux/module.h>
35 #include <linux/threads.h>
36 #include <linux/kernel_stat.h>
37 #include <linux/signal.h>
38 #include <linux/sched.h>
39 #include <linux/ptrace.h>
40 #include <linux/ioport.h>
41 #include <linux/interrupt.h>
42 #include <linux/timex.h>
43 #include <linux/init.h>
44 #include <linux/slab.h>
45 #include <linux/delay.h>
46 #include <linux/irq.h>
47 #include <linux/seq_file.h>
48 #include <linux/cpumask.h>
49 #include <linux/profile.h>
50 #include <linux/bitops.h>
51 #include <linux/list.h>
52 #include <linux/radix-tree.h>
53 #include <linux/mutex.h>
54 #include <linux/bootmem.h>
55
56 #include <asm/uaccess.h>
57 #include <asm/system.h>
58 #include <asm/io.h>
59 #include <asm/pgtable.h>
60 #include <asm/irq.h>
61 #include <asm/cache.h>
62 #include <asm/prom.h>
63 #include <asm/ptrace.h>
64 #include <asm/machdep.h>
65 #include <asm/udbg.h>
66 #ifdef CONFIG_PPC_ISERIES
67 #include <asm/paca.h>
68 #endif
69
70 int __irq_offset_value;
71 static int ppc_spurious_interrupts;
72
73 #ifdef CONFIG_PPC32
74 EXPORT_SYMBOL(__irq_offset_value);
75 atomic_t ppc_n_lost_interrupts;
76
77 #ifndef CONFIG_PPC_MERGE
78 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
79 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
80 #endif
81
82 #ifdef CONFIG_TAU_INT
83 extern int tau_initialized;
84 extern int tau_interrupts(int);
85 #endif
86 #endif /* CONFIG_PPC32 */
87
88 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
89 extern atomic_t ipi_recv;
90 extern atomic_t ipi_sent;
91 #endif
92
93 #ifdef CONFIG_PPC64
94 EXPORT_SYMBOL(irq_desc);
95
96 int distribute_irqs = 1;
97 #endif /* CONFIG_PPC64 */
98
99 int show_interrupts(struct seq_file *p, void *v)
100 {
101         int i = *(loff_t *)v, j;
102         struct irqaction *action;
103         irq_desc_t *desc;
104         unsigned long flags;
105
106         if (i == 0) {
107                 seq_puts(p, "           ");
108                 for_each_online_cpu(j)
109                         seq_printf(p, "CPU%d       ", j);
110                 seq_putc(p, '\n');
111         }
112
113         if (i < NR_IRQS) {
114                 desc = get_irq_desc(i);
115                 spin_lock_irqsave(&desc->lock, flags);
116                 action = desc->action;
117                 if (!action || !action->handler)
118                         goto skip;
119                 seq_printf(p, "%3d: ", i);
120 #ifdef CONFIG_SMP
121                 for_each_online_cpu(j)
122                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
123 #else
124                 seq_printf(p, "%10u ", kstat_irqs(i));
125 #endif /* CONFIG_SMP */
126                 if (desc->chip)
127                         seq_printf(p, " %s ", desc->chip->typename);
128                 else
129                         seq_puts(p, "  None      ");
130                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
131                 seq_printf(p, "    %s", action->name);
132                 for (action = action->next; action; action = action->next)
133                         seq_printf(p, ", %s", action->name);
134                 seq_putc(p, '\n');
135 skip:
136                 spin_unlock_irqrestore(&desc->lock, flags);
137         } else if (i == NR_IRQS) {
138 #ifdef CONFIG_PPC32
139 #ifdef CONFIG_TAU_INT
140                 if (tau_initialized){
141                         seq_puts(p, "TAU: ");
142                         for_each_online_cpu(j)
143                                 seq_printf(p, "%10u ", tau_interrupts(j));
144                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
145                 }
146 #endif
147 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
148                 /* should this be per processor send/receive? */
149                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
150                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
151 #endif
152 #endif /* CONFIG_PPC32 */
153                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
154         }
155         return 0;
156 }
157
158 #ifdef CONFIG_HOTPLUG_CPU
159 void fixup_irqs(cpumask_t map)
160 {
161         unsigned int irq;
162         static int warned;
163
164         for_each_irq(irq) {
165                 cpumask_t mask;
166
167                 if (irq_desc[irq].status & IRQ_PER_CPU)
168                         continue;
169
170                 cpus_and(mask, irq_desc[irq].affinity, map);
171                 if (any_online_cpu(mask) == NR_CPUS) {
172                         printk("Breaking affinity for irq %i\n", irq);
173                         mask = map;
174                 }
175                 if (irq_desc[irq].chip->set_affinity)
176                         irq_desc[irq].chip->set_affinity(irq, mask);
177                 else if (irq_desc[irq].action && !(warned++))
178                         printk("Cannot set affinity for irq %i\n", irq);
179         }
180
181         local_irq_enable();
182         mdelay(1);
183         local_irq_disable();
184 }
185 #endif
186
187 void do_IRQ(struct pt_regs *regs)
188 {
189         unsigned int irq;
190 #ifdef CONFIG_IRQSTACKS
191         struct thread_info *curtp, *irqtp;
192 #endif
193
194         irq_enter();
195
196 #ifdef CONFIG_DEBUG_STACKOVERFLOW
197         /* Debugging check for stack overflow: is there less than 2KB free? */
198         {
199                 long sp;
200
201                 sp = __get_SP() & (THREAD_SIZE-1);
202
203                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
204                         printk("do_IRQ: stack overflow: %ld\n",
205                                 sp - sizeof(struct thread_info));
206                         dump_stack();
207                 }
208         }
209 #endif
210
211         /*
212          * Every platform is required to implement ppc_md.get_irq.
213          * This function will either return an irq number or -1 to
214          * indicate there are no more pending.
215          * The value -2 is for buggy hardware and means that this IRQ
216          * has already been handled. -- Tom
217          */
218         irq = ppc_md.get_irq(regs);
219
220         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
221 #ifdef CONFIG_IRQSTACKS
222                 /* Switch to the irq stack to handle this */
223                 curtp = current_thread_info();
224                 irqtp = hardirq_ctx[smp_processor_id()];
225                 if (curtp != irqtp) {
226                         struct irq_desc *desc = irq_desc + irq;
227                         void *handler = desc->handle_irq;
228                         if (handler == NULL)
229                                 handler = &__do_IRQ;
230                         irqtp->task = curtp->task;
231                         irqtp->flags = 0;
232                         call_handle_irq(irq, desc, regs, irqtp, handler);
233                         irqtp->task = NULL;
234                         if (irqtp->flags)
235                                 set_bits(irqtp->flags, &curtp->flags);
236                 } else
237 #endif
238                         generic_handle_irq(irq, regs);
239         } else if (irq != NO_IRQ_IGNORE)
240                 /* That's not SMP safe ... but who cares ? */
241                 ppc_spurious_interrupts++;
242
243         irq_exit();
244
245 #ifdef CONFIG_PPC_ISERIES
246         if (get_lppaca()->int_dword.fields.decr_int) {
247                 get_lppaca()->int_dword.fields.decr_int = 0;
248                 /* Signal a fake decrementer interrupt */
249                 timer_interrupt(regs);
250         }
251 #endif
252 }
253
254 void __init init_IRQ(void)
255 {
256         ppc_md.init_IRQ();
257 #ifdef CONFIG_PPC64
258         irq_ctx_init();
259 #endif
260 }
261
262
263 #ifdef CONFIG_IRQSTACKS
264 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
265 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
266
267 void irq_ctx_init(void)
268 {
269         struct thread_info *tp;
270         int i;
271
272         for_each_possible_cpu(i) {
273                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
274                 tp = softirq_ctx[i];
275                 tp->cpu = i;
276                 tp->preempt_count = SOFTIRQ_OFFSET;
277
278                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
279                 tp = hardirq_ctx[i];
280                 tp->cpu = i;
281                 tp->preempt_count = HARDIRQ_OFFSET;
282         }
283 }
284
285 static inline void do_softirq_onstack(void)
286 {
287         struct thread_info *curtp, *irqtp;
288
289         curtp = current_thread_info();
290         irqtp = softirq_ctx[smp_processor_id()];
291         irqtp->task = curtp->task;
292         call_do_softirq(irqtp);
293         irqtp->task = NULL;
294 }
295
296 #else
297 #define do_softirq_onstack()    __do_softirq()
298 #endif /* CONFIG_IRQSTACKS */
299
300 void do_softirq(void)
301 {
302         unsigned long flags;
303
304         if (in_interrupt())
305                 return;
306
307         local_irq_save(flags);
308
309         if (local_softirq_pending())
310                 do_softirq_onstack();
311
312         local_irq_restore(flags);
313 }
314 EXPORT_SYMBOL(do_softirq);
315
316
317 /*
318  * IRQ controller and virtual interrupts
319  */
320
321 #ifdef CONFIG_PPC_MERGE
322
323 static LIST_HEAD(irq_hosts);
324 static spinlock_t irq_big_lock = SPIN_LOCK_UNLOCKED;
325 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
326 static unsigned int irq_radix_writer;
327 struct irq_map_entry irq_map[NR_IRQS];
328 static unsigned int irq_virq_count = NR_IRQS;
329 static struct irq_host *irq_default_host;
330
331 struct irq_host *irq_alloc_host(unsigned int revmap_type,
332                                 unsigned int revmap_arg,
333                                 struct irq_host_ops *ops,
334                                 irq_hw_number_t inval_irq)
335 {
336         struct irq_host *host;
337         unsigned int size = sizeof(struct irq_host);
338         unsigned int i;
339         unsigned int *rmap;
340         unsigned long flags;
341
342         /* Allocate structure and revmap table if using linear mapping */
343         if (revmap_type == IRQ_HOST_MAP_LINEAR)
344                 size += revmap_arg * sizeof(unsigned int);
345         if (mem_init_done)
346                 host = kzalloc(size, GFP_KERNEL);
347         else {
348                 host = alloc_bootmem(size);
349                 if (host)
350                         memset(host, 0, size);
351         }
352         if (host == NULL)
353                 return NULL;
354
355         /* Fill structure */
356         host->revmap_type = revmap_type;
357         host->inval_irq = inval_irq;
358         host->ops = ops;
359
360         spin_lock_irqsave(&irq_big_lock, flags);
361
362         /* If it's a legacy controller, check for duplicates and
363          * mark it as allocated (we use irq 0 host pointer for that
364          */
365         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
366                 if (irq_map[0].host != NULL) {
367                         spin_unlock_irqrestore(&irq_big_lock, flags);
368                         /* If we are early boot, we can't free the structure,
369                          * too bad...
370                          * this will be fixed once slab is made available early
371                          * instead of the current cruft
372                          */
373                         if (mem_init_done)
374                                 kfree(host);
375                         return NULL;
376                 }
377                 irq_map[0].host = host;
378         }
379
380         list_add(&host->link, &irq_hosts);
381         spin_unlock_irqrestore(&irq_big_lock, flags);
382
383         /* Additional setups per revmap type */
384         switch(revmap_type) {
385         case IRQ_HOST_MAP_LEGACY:
386                 /* 0 is always the invalid number for legacy */
387                 host->inval_irq = 0;
388                 /* setup us as the host for all legacy interrupts */
389                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
390                         irq_map[i].hwirq = 0;
391                         smp_wmb();
392                         irq_map[i].host = host;
393                         smp_wmb();
394
395                         /* Clear norequest flags */
396                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
397
398                         /* Legacy flags are left to default at this point,
399                          * one can then use irq_create_mapping() to
400                          * explicitely change them
401                          */
402                         ops->map(host, i, i);
403                 }
404                 break;
405         case IRQ_HOST_MAP_LINEAR:
406                 rmap = (unsigned int *)(host + 1);
407                 for (i = 0; i < revmap_arg; i++)
408                         rmap[i] = IRQ_NONE;
409                 host->revmap_data.linear.size = revmap_arg;
410                 smp_wmb();
411                 host->revmap_data.linear.revmap = rmap;
412                 break;
413         default:
414                 break;
415         }
416
417         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
418
419         return host;
420 }
421
422 struct irq_host *irq_find_host(struct device_node *node)
423 {
424         struct irq_host *h, *found = NULL;
425         unsigned long flags;
426
427         /* We might want to match the legacy controller last since
428          * it might potentially be set to match all interrupts in
429          * the absence of a device node. This isn't a problem so far
430          * yet though...
431          */
432         spin_lock_irqsave(&irq_big_lock, flags);
433         list_for_each_entry(h, &irq_hosts, link)
434                 if (h->ops->match == NULL || h->ops->match(h, node)) {
435                         found = h;
436                         break;
437                 }
438         spin_unlock_irqrestore(&irq_big_lock, flags);
439         return found;
440 }
441 EXPORT_SYMBOL_GPL(irq_find_host);
442
443 void irq_set_default_host(struct irq_host *host)
444 {
445         pr_debug("irq: Default host set to @0x%p\n", host);
446
447         irq_default_host = host;
448 }
449
450 void irq_set_virq_count(unsigned int count)
451 {
452         pr_debug("irq: Trying to set virq count to %d\n", count);
453
454         BUG_ON(count < NUM_ISA_INTERRUPTS);
455         if (count < NR_IRQS)
456                 irq_virq_count = count;
457 }
458
459 /* radix tree not lockless safe ! we use a brlock-type mecanism
460  * for now, until we can use a lockless radix tree
461  */
462 static void irq_radix_wrlock(unsigned long *flags)
463 {
464         unsigned int cpu, ok;
465
466         spin_lock_irqsave(&irq_big_lock, *flags);
467         irq_radix_writer = 1;
468         smp_mb();
469         do {
470                 barrier();
471                 ok = 1;
472                 for_each_possible_cpu(cpu) {
473                         if (per_cpu(irq_radix_reader, cpu)) {
474                                 ok = 0;
475                                 break;
476                         }
477                 }
478                 if (!ok)
479                         cpu_relax();
480         } while(!ok);
481 }
482
483 static void irq_radix_wrunlock(unsigned long flags)
484 {
485         smp_wmb();
486         irq_radix_writer = 0;
487         spin_unlock_irqrestore(&irq_big_lock, flags);
488 }
489
490 static void irq_radix_rdlock(unsigned long *flags)
491 {
492         local_irq_save(*flags);
493         __get_cpu_var(irq_radix_reader) = 1;
494         smp_mb();
495         if (likely(irq_radix_writer == 0))
496                 return;
497         __get_cpu_var(irq_radix_reader) = 0;
498         smp_wmb();
499         spin_lock(&irq_big_lock);
500         __get_cpu_var(irq_radix_reader) = 1;
501         spin_unlock(&irq_big_lock);
502 }
503
504 static void irq_radix_rdunlock(unsigned long flags)
505 {
506         __get_cpu_var(irq_radix_reader) = 0;
507         local_irq_restore(flags);
508 }
509
510
511 unsigned int irq_create_mapping(struct irq_host *host,
512                                 irq_hw_number_t hwirq)
513 {
514         unsigned int virq, hint;
515
516         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
517
518         /* Look for default host if nececssary */
519         if (host == NULL)
520                 host = irq_default_host;
521         if (host == NULL) {
522                 printk(KERN_WARNING "irq_create_mapping called for"
523                        " NULL host, hwirq=%lx\n", hwirq);
524                 WARN_ON(1);
525                 return NO_IRQ;
526         }
527         pr_debug("irq: -> using host @%p\n", host);
528
529         /* Check if mapping already exist, if it does, call
530          * host->ops->map() to update the flags
531          */
532         virq = irq_find_mapping(host, hwirq);
533         if (virq != IRQ_NONE) {
534                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
535                 return virq;
536         }
537
538         /* Get a virtual interrupt number */
539         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
540                 /* Handle legacy */
541                 virq = (unsigned int)hwirq;
542                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
543                         return NO_IRQ;
544                 return virq;
545         } else {
546                 /* Allocate a virtual interrupt number */
547                 hint = hwirq % irq_virq_count;
548                 virq = irq_alloc_virt(host, 1, hint);
549                 if (virq == NO_IRQ) {
550                         pr_debug("irq: -> virq allocation failed\n");
551                         return NO_IRQ;
552                 }
553         }
554         pr_debug("irq: -> obtained virq %d\n", virq);
555
556         /* Clear IRQ_NOREQUEST flag */
557         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
558
559         /* map it */
560         smp_wmb();
561         irq_map[virq].hwirq = hwirq;
562         smp_mb();
563         if (host->ops->map(host, virq, hwirq)) {
564                 pr_debug("irq: -> mapping failed, freeing\n");
565                 irq_free_virt(virq, 1);
566                 return NO_IRQ;
567         }
568         return virq;
569 }
570 EXPORT_SYMBOL_GPL(irq_create_mapping);
571
572 extern unsigned int irq_create_of_mapping(struct device_node *controller,
573                                           u32 *intspec, unsigned int intsize)
574 {
575         struct irq_host *host;
576         irq_hw_number_t hwirq;
577         unsigned int type = IRQ_TYPE_NONE;
578         unsigned int virq;
579
580         if (controller == NULL)
581                 host = irq_default_host;
582         else
583                 host = irq_find_host(controller);
584         if (host == NULL) {
585                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
586                        controller->full_name);
587                 return NO_IRQ;
588         }
589
590         /* If host has no translation, then we assume interrupt line */
591         if (host->ops->xlate == NULL)
592                 hwirq = intspec[0];
593         else {
594                 if (host->ops->xlate(host, controller, intspec, intsize,
595                                      &hwirq, &type))
596                         return NO_IRQ;
597         }
598
599         /* Create mapping */
600         virq = irq_create_mapping(host, hwirq);
601         if (virq == NO_IRQ)
602                 return virq;
603
604         /* Set type if specified and different than the current one */
605         if (type != IRQ_TYPE_NONE &&
606             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
607                 set_irq_type(virq, type);
608         return virq;
609 }
610 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
611
612 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
613 {
614         struct of_irq oirq;
615
616         if (of_irq_map_one(dev, index, &oirq))
617                 return NO_IRQ;
618
619         return irq_create_of_mapping(oirq.controller, oirq.specifier,
620                                      oirq.size);
621 }
622 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
623
624 void irq_dispose_mapping(unsigned int virq)
625 {
626         struct irq_host *host = irq_map[virq].host;
627         irq_hw_number_t hwirq;
628         unsigned long flags;
629
630         WARN_ON (host == NULL);
631         if (host == NULL)
632                 return;
633
634         /* Never unmap legacy interrupts */
635         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
636                 return;
637
638         /* remove chip and handler */
639         set_irq_chip_and_handler(virq, NULL, NULL);
640
641         /* Make sure it's completed */
642         synchronize_irq(virq);
643
644         /* Tell the PIC about it */
645         if (host->ops->unmap)
646                 host->ops->unmap(host, virq);
647         smp_mb();
648
649         /* Clear reverse map */
650         hwirq = irq_map[virq].hwirq;
651         switch(host->revmap_type) {
652         case IRQ_HOST_MAP_LINEAR:
653                 if (hwirq < host->revmap_data.linear.size)
654                         host->revmap_data.linear.revmap[hwirq] = IRQ_NONE;
655                 break;
656         case IRQ_HOST_MAP_TREE:
657                 /* Check if radix tree allocated yet */
658                 if (host->revmap_data.tree.gfp_mask == 0)
659                         break;
660                 irq_radix_wrlock(&flags);
661                 radix_tree_delete(&host->revmap_data.tree, hwirq);
662                 irq_radix_wrunlock(flags);
663                 break;
664         }
665
666         /* Destroy map */
667         smp_mb();
668         irq_map[virq].hwirq = host->inval_irq;
669
670         /* Set some flags */
671         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
672
673         /* Free it */
674         irq_free_virt(virq, 1);
675 }
676 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
677
678 unsigned int irq_find_mapping(struct irq_host *host,
679                               irq_hw_number_t hwirq)
680 {
681         unsigned int i;
682         unsigned int hint = hwirq % irq_virq_count;
683
684         /* Look for default host if nececssary */
685         if (host == NULL)
686                 host = irq_default_host;
687         if (host == NULL)
688                 return NO_IRQ;
689
690         /* legacy -> bail early */
691         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
692                 return hwirq;
693
694         /* Slow path does a linear search of the map */
695         if (hint < NUM_ISA_INTERRUPTS)
696                 hint = NUM_ISA_INTERRUPTS;
697         i = hint;
698         do  {
699                 if (irq_map[i].host == host &&
700                     irq_map[i].hwirq == hwirq)
701                         return i;
702                 i++;
703                 if (i >= irq_virq_count)
704                         i = NUM_ISA_INTERRUPTS;
705         } while(i != hint);
706         return NO_IRQ;
707 }
708 EXPORT_SYMBOL_GPL(irq_find_mapping);
709
710
711 unsigned int irq_radix_revmap(struct irq_host *host,
712                               irq_hw_number_t hwirq)
713 {
714         struct radix_tree_root *tree;
715         struct irq_map_entry *ptr;
716         unsigned int virq;
717         unsigned long flags;
718
719         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
720
721         /* Check if the radix tree exist yet. We test the value of
722          * the gfp_mask for that. Sneaky but saves another int in the
723          * structure. If not, we fallback to slow mode
724          */
725         tree = &host->revmap_data.tree;
726         if (tree->gfp_mask == 0)
727                 return irq_find_mapping(host, hwirq);
728
729         /* Now try to resolve */
730         irq_radix_rdlock(&flags);
731         ptr = radix_tree_lookup(tree, hwirq);
732         irq_radix_rdunlock(flags);
733
734         /* Found it, return */
735         if (ptr) {
736                 virq = ptr - irq_map;
737                 return virq;
738         }
739
740         /* If not there, try to insert it */
741         virq = irq_find_mapping(host, hwirq);
742         if (virq != NO_IRQ) {
743                 irq_radix_wrlock(&flags);
744                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
745                 irq_radix_wrunlock(flags);
746         }
747         return virq;
748 }
749
750 unsigned int irq_linear_revmap(struct irq_host *host,
751                                irq_hw_number_t hwirq)
752 {
753         unsigned int *revmap;
754
755         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
756
757         /* Check revmap bounds */
758         if (unlikely(hwirq >= host->revmap_data.linear.size))
759                 return irq_find_mapping(host, hwirq);
760
761         /* Check if revmap was allocated */
762         revmap = host->revmap_data.linear.revmap;
763         if (unlikely(revmap == NULL))
764                 return irq_find_mapping(host, hwirq);
765
766         /* Fill up revmap with slow path if no mapping found */
767         if (unlikely(revmap[hwirq] == NO_IRQ))
768                 revmap[hwirq] = irq_find_mapping(host, hwirq);
769
770         return revmap[hwirq];
771 }
772
773 unsigned int irq_alloc_virt(struct irq_host *host,
774                             unsigned int count,
775                             unsigned int hint)
776 {
777         unsigned long flags;
778         unsigned int i, j, found = NO_IRQ;
779         unsigned int limit = irq_virq_count - count;
780
781         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
782                 return NO_IRQ;
783
784         spin_lock_irqsave(&irq_big_lock, flags);
785
786         /* Use hint for 1 interrupt if any */
787         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
788             hint < irq_virq_count && irq_map[hint].host == NULL) {
789                 found = hint;
790                 goto hint_found;
791         }
792
793         /* Look for count consecutive numbers in the allocatable
794          * (non-legacy) space
795          */
796         for (i = NUM_ISA_INTERRUPTS; i <= limit; ) {
797                 for (j = i; j < (i + count); j++)
798                         if (irq_map[j].host != NULL) {
799                                 i = j + 1;
800                                 continue;
801                         }
802                 found = i;
803                 break;
804         }
805         if (found == NO_IRQ) {
806                 spin_unlock_irqrestore(&irq_big_lock, flags);
807                 return NO_IRQ;
808         }
809  hint_found:
810         for (i = found; i < (found + count); i++) {
811                 irq_map[i].hwirq = host->inval_irq;
812                 smp_wmb();
813                 irq_map[i].host = host;
814         }
815         spin_unlock_irqrestore(&irq_big_lock, flags);
816         return found;
817 }
818
819 void irq_free_virt(unsigned int virq, unsigned int count)
820 {
821         unsigned long flags;
822         unsigned int i;
823
824         WARN_ON (virq < NUM_ISA_INTERRUPTS);
825         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
826
827         spin_lock_irqsave(&irq_big_lock, flags);
828         for (i = virq; i < (virq + count); i++) {
829                 struct irq_host *host;
830
831                 if (i < NUM_ISA_INTERRUPTS ||
832                     (virq + count) > irq_virq_count)
833                         continue;
834
835                 host = irq_map[i].host;
836                 irq_map[i].hwirq = host->inval_irq;
837                 smp_wmb();
838                 irq_map[i].host = NULL;
839         }
840         spin_unlock_irqrestore(&irq_big_lock, flags);
841 }
842
843 void irq_early_init(void)
844 {
845         unsigned int i;
846
847         for (i = 0; i < NR_IRQS; i++)
848                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
849 }
850
851 /* We need to create the radix trees late */
852 static int irq_late_init(void)
853 {
854         struct irq_host *h;
855         unsigned long flags;
856
857         irq_radix_wrlock(&flags);
858         list_for_each_entry(h, &irq_hosts, link) {
859                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
860                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
861         }
862         irq_radix_wrunlock(flags);
863
864         return 0;
865 }
866 arch_initcall(irq_late_init);
867
868 #endif /* CONFIG_PPC_MERGE */
869
870 #ifdef CONFIG_PCI_MSI
871 int pci_enable_msi(struct pci_dev * pdev)
872 {
873         if (ppc_md.enable_msi)
874                 return ppc_md.enable_msi(pdev);
875         else
876                 return -1;
877 }
878
879 void pci_disable_msi(struct pci_dev * pdev)
880 {
881         if (ppc_md.disable_msi)
882                 ppc_md.disable_msi(pdev);
883 }
884
885 void pci_scan_msi_device(struct pci_dev *dev) {}
886 int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) {return -1;}
887 void pci_disable_msix(struct pci_dev *dev) {}
888 void msi_remove_pci_irq_vectors(struct pci_dev *dev) {}
889 void disable_msi_mode(struct pci_dev *dev, int pos, int type) {}
890 void pci_no_msi(void) {}
891
892 #endif
893
894 #ifdef CONFIG_PPC64
895 static int __init setup_noirqdistrib(char *str)
896 {
897         distribute_irqs = 0;
898         return 1;
899 }
900
901 __setup("noirqdistrib", setup_noirqdistrib);
902 #endif /* CONFIG_PPC64 */