Merge branch 'for-linus' of git://neil.brown.name/md
[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  *
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 #ifndef CONFIG_PPC_MERGE
81 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
82 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
83 #endif
84
85 #ifdef CONFIG_TAU_INT
86 extern int tau_initialized;
87 extern int tau_interrupts(int);
88 #endif
89 #endif /* CONFIG_PPC32 */
90
91 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
92 extern atomic_t ipi_recv;
93 extern atomic_t ipi_sent;
94 #endif
95
96 #ifdef CONFIG_PPC64
97 EXPORT_SYMBOL(irq_desc);
98
99 int distribute_irqs = 1;
100
101 static inline notrace unsigned long get_hard_enabled(void)
102 {
103         unsigned long enabled;
104
105         __asm__ __volatile__("lbz %0,%1(13)"
106         : "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
107
108         return enabled;
109 }
110
111 static inline notrace void set_soft_enabled(unsigned long enable)
112 {
113         __asm__ __volatile__("stb %0,%1(13)"
114         : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
115 }
116
117 notrace void raw_local_irq_restore(unsigned long en)
118 {
119         /*
120          * get_paca()->soft_enabled = en;
121          * Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
122          * That was allowed before, and in such a case we do need to take care
123          * that gcc will set soft_enabled directly via r13, not choose to use
124          * an intermediate register, lest we're preempted to a different cpu.
125          */
126         set_soft_enabled(en);
127         if (!en)
128                 return;
129
130         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
131                 /*
132                  * Do we need to disable preemption here?  Not really: in the
133                  * unlikely event that we're preempted to a different cpu in
134                  * between getting r13, loading its lppaca_ptr, and loading
135                  * its any_int, we might call iseries_handle_interrupts without
136                  * an interrupt pending on the new cpu, but that's no disaster,
137                  * is it?  And the business of preempting us off the old cpu
138                  * would itself involve a local_irq_restore which handles the
139                  * interrupt to that cpu.
140                  *
141                  * But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
142                  * to avoid any preemption checking added into get_paca().
143                  */
144                 if (local_paca->lppaca_ptr->int_dword.any_int)
145                         iseries_handle_interrupts();
146         }
147
148         /*
149          * if (get_paca()->hard_enabled) return;
150          * But again we need to take care that gcc gets hard_enabled directly
151          * via r13, not choose to use an intermediate register, lest we're
152          * preempted to a different cpu in between the two instructions.
153          */
154         if (get_hard_enabled())
155                 return;
156
157         /*
158          * Need to hard-enable interrupts here.  Since currently disabled,
159          * no need to take further asm precautions against preemption; but
160          * use local_paca instead of get_paca() to avoid preemption checking.
161          */
162         local_paca->hard_enabled = en;
163         if ((int)mfspr(SPRN_DEC) < 0)
164                 mtspr(SPRN_DEC, 1);
165
166         /*
167          * Force the delivery of pending soft-disabled interrupts on PS3.
168          * Any HV call will have this side effect.
169          */
170         if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
171                 u64 tmp;
172                 lv1_get_version_info(&tmp);
173         }
174
175         __hard_irq_enable();
176 }
177 EXPORT_SYMBOL(raw_local_irq_restore);
178 #endif /* CONFIG_PPC64 */
179
180 int show_interrupts(struct seq_file *p, void *v)
181 {
182         int i = *(loff_t *)v, j;
183         struct irqaction *action;
184         irq_desc_t *desc;
185         unsigned long flags;
186
187         if (i == 0) {
188                 seq_puts(p, "           ");
189                 for_each_online_cpu(j)
190                         seq_printf(p, "CPU%d       ", j);
191                 seq_putc(p, '\n');
192         }
193
194         if (i < NR_IRQS) {
195                 desc = get_irq_desc(i);
196                 spin_lock_irqsave(&desc->lock, flags);
197                 action = desc->action;
198                 if (!action || !action->handler)
199                         goto skip;
200                 seq_printf(p, "%3d: ", i);
201 #ifdef CONFIG_SMP
202                 for_each_online_cpu(j)
203                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
204 #else
205                 seq_printf(p, "%10u ", kstat_irqs(i));
206 #endif /* CONFIG_SMP */
207                 if (desc->chip)
208                         seq_printf(p, " %s ", desc->chip->typename);
209                 else
210                         seq_puts(p, "  None      ");
211                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
212                 seq_printf(p, "    %s", action->name);
213                 for (action = action->next; action; action = action->next)
214                         seq_printf(p, ", %s", action->name);
215                 seq_putc(p, '\n');
216 skip:
217                 spin_unlock_irqrestore(&desc->lock, flags);
218         } else if (i == NR_IRQS) {
219 #ifdef CONFIG_PPC32
220 #ifdef CONFIG_TAU_INT
221                 if (tau_initialized){
222                         seq_puts(p, "TAU: ");
223                         for_each_online_cpu(j)
224                                 seq_printf(p, "%10u ", tau_interrupts(j));
225                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
226                 }
227 #endif
228 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
229                 /* should this be per processor send/receive? */
230                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
231                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
232 #endif
233 #endif /* CONFIG_PPC32 */
234                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
235         }
236         return 0;
237 }
238
239 #ifdef CONFIG_HOTPLUG_CPU
240 void fixup_irqs(cpumask_t map)
241 {
242         unsigned int irq;
243         static int warned;
244
245         for_each_irq(irq) {
246                 cpumask_t mask;
247
248                 if (irq_desc[irq].status & IRQ_PER_CPU)
249                         continue;
250
251                 cpus_and(mask, irq_desc[irq].affinity, map);
252                 if (any_online_cpu(mask) == NR_CPUS) {
253                         printk("Breaking affinity for irq %i\n", irq);
254                         mask = map;
255                 }
256                 if (irq_desc[irq].chip->set_affinity)
257                         irq_desc[irq].chip->set_affinity(irq, mask);
258                 else if (irq_desc[irq].action && !(warned++))
259                         printk("Cannot set affinity for irq %i\n", irq);
260         }
261
262         local_irq_enable();
263         mdelay(1);
264         local_irq_disable();
265 }
266 #endif
267
268 void do_IRQ(struct pt_regs *regs)
269 {
270         struct pt_regs *old_regs = set_irq_regs(regs);
271         unsigned int irq;
272 #ifdef CONFIG_IRQSTACKS
273         struct thread_info *curtp, *irqtp;
274 #endif
275
276         irq_enter();
277
278 #ifdef CONFIG_DEBUG_STACKOVERFLOW
279         /* Debugging check for stack overflow: is there less than 2KB free? */
280         {
281                 long sp;
282
283                 sp = __get_SP() & (THREAD_SIZE-1);
284
285                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
286                         printk("do_IRQ: stack overflow: %ld\n",
287                                 sp - sizeof(struct thread_info));
288                         dump_stack();
289                 }
290         }
291 #endif
292
293         /*
294          * Every platform is required to implement ppc_md.get_irq.
295          * This function will either return an irq number or NO_IRQ to
296          * indicate there are no more pending.
297          * The value NO_IRQ_IGNORE is for buggy hardware and means that this
298          * IRQ has already been handled. -- Tom
299          */
300         irq = ppc_md.get_irq();
301
302         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
303 #ifdef CONFIG_IRQSTACKS
304                 /* Switch to the irq stack to handle this */
305                 curtp = current_thread_info();
306                 irqtp = hardirq_ctx[smp_processor_id()];
307                 if (curtp != irqtp) {
308                         struct irq_desc *desc = irq_desc + irq;
309                         void *handler = desc->handle_irq;
310                         unsigned long saved_sp_limit = current->thread.ksp_limit;
311                         if (handler == NULL)
312                                 handler = &__do_IRQ;
313                         irqtp->task = curtp->task;
314                         irqtp->flags = 0;
315
316                         /* Copy the softirq bits in preempt_count so that the
317                          * softirq checks work in the hardirq context.
318                          */
319                         irqtp->preempt_count =
320                                 (irqtp->preempt_count & ~SOFTIRQ_MASK) |
321                                 (curtp->preempt_count & SOFTIRQ_MASK);
322
323                         current->thread.ksp_limit = (unsigned long)irqtp +
324                                 _ALIGN_UP(sizeof(struct thread_info), 16);
325                         call_handle_irq(irq, desc, irqtp, handler);
326                         current->thread.ksp_limit = saved_sp_limit;
327                         irqtp->task = NULL;
328
329
330                         /* Set any flag that may have been set on the
331                          * alternate stack
332                          */
333                         if (irqtp->flags)
334                                 set_bits(irqtp->flags, &curtp->flags);
335                 } else
336 #endif
337                         generic_handle_irq(irq);
338         } else if (irq != NO_IRQ_IGNORE)
339                 /* That's not SMP safe ... but who cares ? */
340                 ppc_spurious_interrupts++;
341
342         irq_exit();
343         set_irq_regs(old_regs);
344
345 #ifdef CONFIG_PPC_ISERIES
346         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
347                         get_lppaca()->int_dword.fields.decr_int) {
348                 get_lppaca()->int_dword.fields.decr_int = 0;
349                 /* Signal a fake decrementer interrupt */
350                 timer_interrupt(regs);
351         }
352 #endif
353 }
354
355 void __init init_IRQ(void)
356 {
357         if (ppc_md.init_IRQ)
358                 ppc_md.init_IRQ();
359
360         exc_lvl_ctx_init();
361
362         irq_ctx_init();
363 }
364
365 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
366 struct thread_info   *critirq_ctx[NR_CPUS] __read_mostly;
367 struct thread_info    *dbgirq_ctx[NR_CPUS] __read_mostly;
368 struct thread_info *mcheckirq_ctx[NR_CPUS] __read_mostly;
369
370 void exc_lvl_ctx_init(void)
371 {
372         struct thread_info *tp;
373         int i;
374
375         for_each_possible_cpu(i) {
376                 memset((void *)critirq_ctx[i], 0, THREAD_SIZE);
377                 tp = critirq_ctx[i];
378                 tp->cpu = i;
379                 tp->preempt_count = 0;
380
381 #ifdef CONFIG_BOOKE
382                 memset((void *)dbgirq_ctx[i], 0, THREAD_SIZE);
383                 tp = dbgirq_ctx[i];
384                 tp->cpu = i;
385                 tp->preempt_count = 0;
386
387                 memset((void *)mcheckirq_ctx[i], 0, THREAD_SIZE);
388                 tp = mcheckirq_ctx[i];
389                 tp->cpu = i;
390                 tp->preempt_count = HARDIRQ_OFFSET;
391 #endif
392         }
393 }
394 #endif
395
396 #ifdef CONFIG_IRQSTACKS
397 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
398 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
399
400 void irq_ctx_init(void)
401 {
402         struct thread_info *tp;
403         int i;
404
405         for_each_possible_cpu(i) {
406                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
407                 tp = softirq_ctx[i];
408                 tp->cpu = i;
409                 tp->preempt_count = 0;
410
411                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
412                 tp = hardirq_ctx[i];
413                 tp->cpu = i;
414                 tp->preempt_count = HARDIRQ_OFFSET;
415         }
416 }
417
418 static inline void do_softirq_onstack(void)
419 {
420         struct thread_info *curtp, *irqtp;
421         unsigned long saved_sp_limit = current->thread.ksp_limit;
422
423         curtp = current_thread_info();
424         irqtp = softirq_ctx[smp_processor_id()];
425         irqtp->task = curtp->task;
426         current->thread.ksp_limit = (unsigned long)irqtp +
427                                     _ALIGN_UP(sizeof(struct thread_info), 16);
428         call_do_softirq(irqtp);
429         current->thread.ksp_limit = saved_sp_limit;
430         irqtp->task = NULL;
431 }
432
433 #else
434 #define do_softirq_onstack()    __do_softirq()
435 #endif /* CONFIG_IRQSTACKS */
436
437 void do_softirq(void)
438 {
439         unsigned long flags;
440
441         if (in_interrupt())
442                 return;
443
444         local_irq_save(flags);
445
446         if (local_softirq_pending())
447                 do_softirq_onstack();
448
449         local_irq_restore(flags);
450 }
451
452
453 /*
454  * IRQ controller and virtual interrupts
455  */
456
457 #ifdef CONFIG_PPC_MERGE
458
459 static LIST_HEAD(irq_hosts);
460 static DEFINE_SPINLOCK(irq_big_lock);
461 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
462 static unsigned int irq_radix_writer;
463 struct irq_map_entry irq_map[NR_IRQS];
464 static unsigned int irq_virq_count = NR_IRQS;
465 static struct irq_host *irq_default_host;
466
467 irq_hw_number_t virq_to_hw(unsigned int virq)
468 {
469         return irq_map[virq].hwirq;
470 }
471 EXPORT_SYMBOL_GPL(virq_to_hw);
472
473 static int default_irq_host_match(struct irq_host *h, struct device_node *np)
474 {
475         return h->of_node != NULL && h->of_node == np;
476 }
477
478 struct irq_host *irq_alloc_host(struct device_node *of_node,
479                                 unsigned int revmap_type,
480                                 unsigned int revmap_arg,
481                                 struct irq_host_ops *ops,
482                                 irq_hw_number_t inval_irq)
483 {
484         struct irq_host *host;
485         unsigned int size = sizeof(struct irq_host);
486         unsigned int i;
487         unsigned int *rmap;
488         unsigned long flags;
489
490         /* Allocate structure and revmap table if using linear mapping */
491         if (revmap_type == IRQ_HOST_MAP_LINEAR)
492                 size += revmap_arg * sizeof(unsigned int);
493         host = zalloc_maybe_bootmem(size, GFP_KERNEL);
494         if (host == NULL)
495                 return NULL;
496
497         /* Fill structure */
498         host->revmap_type = revmap_type;
499         host->inval_irq = inval_irq;
500         host->ops = ops;
501         host->of_node = of_node_get(of_node);
502
503         if (host->ops->match == NULL)
504                 host->ops->match = default_irq_host_match;
505
506         spin_lock_irqsave(&irq_big_lock, flags);
507
508         /* If it's a legacy controller, check for duplicates and
509          * mark it as allocated (we use irq 0 host pointer for that
510          */
511         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
512                 if (irq_map[0].host != NULL) {
513                         spin_unlock_irqrestore(&irq_big_lock, flags);
514                         /* If we are early boot, we can't free the structure,
515                          * too bad...
516                          * this will be fixed once slab is made available early
517                          * instead of the current cruft
518                          */
519                         if (mem_init_done)
520                                 kfree(host);
521                         return NULL;
522                 }
523                 irq_map[0].host = host;
524         }
525
526         list_add(&host->link, &irq_hosts);
527         spin_unlock_irqrestore(&irq_big_lock, flags);
528
529         /* Additional setups per revmap type */
530         switch(revmap_type) {
531         case IRQ_HOST_MAP_LEGACY:
532                 /* 0 is always the invalid number for legacy */
533                 host->inval_irq = 0;
534                 /* setup us as the host for all legacy interrupts */
535                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
536                         irq_map[i].hwirq = i;
537                         smp_wmb();
538                         irq_map[i].host = host;
539                         smp_wmb();
540
541                         /* Clear norequest flags */
542                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
543
544                         /* Legacy flags are left to default at this point,
545                          * one can then use irq_create_mapping() to
546                          * explicitly change them
547                          */
548                         ops->map(host, i, i);
549                 }
550                 break;
551         case IRQ_HOST_MAP_LINEAR:
552                 rmap = (unsigned int *)(host + 1);
553                 for (i = 0; i < revmap_arg; i++)
554                         rmap[i] = NO_IRQ;
555                 host->revmap_data.linear.size = revmap_arg;
556                 smp_wmb();
557                 host->revmap_data.linear.revmap = rmap;
558                 break;
559         default:
560                 break;
561         }
562
563         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
564
565         return host;
566 }
567
568 struct irq_host *irq_find_host(struct device_node *node)
569 {
570         struct irq_host *h, *found = NULL;
571         unsigned long flags;
572
573         /* We might want to match the legacy controller last since
574          * it might potentially be set to match all interrupts in
575          * the absence of a device node. This isn't a problem so far
576          * yet though...
577          */
578         spin_lock_irqsave(&irq_big_lock, flags);
579         list_for_each_entry(h, &irq_hosts, link)
580                 if (h->ops->match(h, node)) {
581                         found = h;
582                         break;
583                 }
584         spin_unlock_irqrestore(&irq_big_lock, flags);
585         return found;
586 }
587 EXPORT_SYMBOL_GPL(irq_find_host);
588
589 void irq_set_default_host(struct irq_host *host)
590 {
591         pr_debug("irq: Default host set to @0x%p\n", host);
592
593         irq_default_host = host;
594 }
595
596 void irq_set_virq_count(unsigned int count)
597 {
598         pr_debug("irq: Trying to set virq count to %d\n", count);
599
600         BUG_ON(count < NUM_ISA_INTERRUPTS);
601         if (count < NR_IRQS)
602                 irq_virq_count = count;
603 }
604
605 /* radix tree not lockless safe ! we use a brlock-type mecanism
606  * for now, until we can use a lockless radix tree
607  */
608 static void irq_radix_wrlock(unsigned long *flags)
609 {
610         unsigned int cpu, ok;
611
612         spin_lock_irqsave(&irq_big_lock, *flags);
613         irq_radix_writer = 1;
614         smp_mb();
615         do {
616                 barrier();
617                 ok = 1;
618                 for_each_possible_cpu(cpu) {
619                         if (per_cpu(irq_radix_reader, cpu)) {
620                                 ok = 0;
621                                 break;
622                         }
623                 }
624                 if (!ok)
625                         cpu_relax();
626         } while(!ok);
627 }
628
629 static void irq_radix_wrunlock(unsigned long flags)
630 {
631         smp_wmb();
632         irq_radix_writer = 0;
633         spin_unlock_irqrestore(&irq_big_lock, flags);
634 }
635
636 static void irq_radix_rdlock(unsigned long *flags)
637 {
638         local_irq_save(*flags);
639         __get_cpu_var(irq_radix_reader) = 1;
640         smp_mb();
641         if (likely(irq_radix_writer == 0))
642                 return;
643         __get_cpu_var(irq_radix_reader) = 0;
644         smp_wmb();
645         spin_lock(&irq_big_lock);
646         __get_cpu_var(irq_radix_reader) = 1;
647         spin_unlock(&irq_big_lock);
648 }
649
650 static void irq_radix_rdunlock(unsigned long flags)
651 {
652         __get_cpu_var(irq_radix_reader) = 0;
653         local_irq_restore(flags);
654 }
655
656 static int irq_setup_virq(struct irq_host *host, unsigned int virq,
657                             irq_hw_number_t hwirq)
658 {
659         /* Clear IRQ_NOREQUEST flag */
660         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
661
662         /* map it */
663         smp_wmb();
664         irq_map[virq].hwirq = hwirq;
665         smp_mb();
666
667         if (host->ops->map(host, virq, hwirq)) {
668                 pr_debug("irq: -> mapping failed, freeing\n");
669                 irq_free_virt(virq, 1);
670                 return -1;
671         }
672
673         return 0;
674 }
675
676 unsigned int irq_create_direct_mapping(struct irq_host *host)
677 {
678         unsigned int virq;
679
680         if (host == NULL)
681                 host = irq_default_host;
682
683         BUG_ON(host == NULL);
684         WARN_ON(host->revmap_type != IRQ_HOST_MAP_NOMAP);
685
686         virq = irq_alloc_virt(host, 1, 0);
687         if (virq == NO_IRQ) {
688                 pr_debug("irq: create_direct virq allocation failed\n");
689                 return NO_IRQ;
690         }
691
692         pr_debug("irq: create_direct obtained virq %d\n", virq);
693
694         if (irq_setup_virq(host, virq, virq))
695                 return NO_IRQ;
696
697         return virq;
698 }
699
700 unsigned int irq_create_mapping(struct irq_host *host,
701                                 irq_hw_number_t hwirq)
702 {
703         unsigned int virq, hint;
704
705         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
706
707         /* Look for default host if nececssary */
708         if (host == NULL)
709                 host = irq_default_host;
710         if (host == NULL) {
711                 printk(KERN_WARNING "irq_create_mapping called for"
712                        " NULL host, hwirq=%lx\n", hwirq);
713                 WARN_ON(1);
714                 return NO_IRQ;
715         }
716         pr_debug("irq: -> using host @%p\n", host);
717
718         /* Check if mapping already exist, if it does, call
719          * host->ops->map() to update the flags
720          */
721         virq = irq_find_mapping(host, hwirq);
722         if (virq != NO_IRQ) {
723                 if (host->ops->remap)
724                         host->ops->remap(host, virq, hwirq);
725                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
726                 return virq;
727         }
728
729         /* Get a virtual interrupt number */
730         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
731                 /* Handle legacy */
732                 virq = (unsigned int)hwirq;
733                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
734                         return NO_IRQ;
735                 return virq;
736         } else {
737                 /* Allocate a virtual interrupt number */
738                 hint = hwirq % irq_virq_count;
739                 virq = irq_alloc_virt(host, 1, hint);
740                 if (virq == NO_IRQ) {
741                         pr_debug("irq: -> virq allocation failed\n");
742                         return NO_IRQ;
743                 }
744         }
745         pr_debug("irq: -> obtained virq %d\n", virq);
746
747         if (irq_setup_virq(host, virq, hwirq))
748                 return NO_IRQ;
749
750         return virq;
751 }
752 EXPORT_SYMBOL_GPL(irq_create_mapping);
753
754 unsigned int irq_create_of_mapping(struct device_node *controller,
755                                    u32 *intspec, unsigned int intsize)
756 {
757         struct irq_host *host;
758         irq_hw_number_t hwirq;
759         unsigned int type = IRQ_TYPE_NONE;
760         unsigned int virq;
761
762         if (controller == NULL)
763                 host = irq_default_host;
764         else
765                 host = irq_find_host(controller);
766         if (host == NULL) {
767                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
768                        controller->full_name);
769                 return NO_IRQ;
770         }
771
772         /* If host has no translation, then we assume interrupt line */
773         if (host->ops->xlate == NULL)
774                 hwirq = intspec[0];
775         else {
776                 if (host->ops->xlate(host, controller, intspec, intsize,
777                                      &hwirq, &type))
778                         return NO_IRQ;
779         }
780
781         /* Create mapping */
782         virq = irq_create_mapping(host, hwirq);
783         if (virq == NO_IRQ)
784                 return virq;
785
786         /* Set type if specified and different than the current one */
787         if (type != IRQ_TYPE_NONE &&
788             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
789                 set_irq_type(virq, type);
790         return virq;
791 }
792 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
793
794 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
795 {
796         struct of_irq oirq;
797
798         if (of_irq_map_one(dev, index, &oirq))
799                 return NO_IRQ;
800
801         return irq_create_of_mapping(oirq.controller, oirq.specifier,
802                                      oirq.size);
803 }
804 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
805
806 void irq_dispose_mapping(unsigned int virq)
807 {
808         struct irq_host *host;
809         irq_hw_number_t hwirq;
810         unsigned long flags;
811
812         if (virq == NO_IRQ)
813                 return;
814
815         host = irq_map[virq].host;
816         WARN_ON (host == NULL);
817         if (host == NULL)
818                 return;
819
820         /* Never unmap legacy interrupts */
821         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
822                 return;
823
824         /* remove chip and handler */
825         set_irq_chip_and_handler(virq, NULL, NULL);
826
827         /* Make sure it's completed */
828         synchronize_irq(virq);
829
830         /* Tell the PIC about it */
831         if (host->ops->unmap)
832                 host->ops->unmap(host, virq);
833         smp_mb();
834
835         /* Clear reverse map */
836         hwirq = irq_map[virq].hwirq;
837         switch(host->revmap_type) {
838         case IRQ_HOST_MAP_LINEAR:
839                 if (hwirq < host->revmap_data.linear.size)
840                         host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
841                 break;
842         case IRQ_HOST_MAP_TREE:
843                 /* Check if radix tree allocated yet */
844                 if (host->revmap_data.tree.gfp_mask == 0)
845                         break;
846                 irq_radix_wrlock(&flags);
847                 radix_tree_delete(&host->revmap_data.tree, hwirq);
848                 irq_radix_wrunlock(flags);
849                 break;
850         }
851
852         /* Destroy map */
853         smp_mb();
854         irq_map[virq].hwirq = host->inval_irq;
855
856         /* Set some flags */
857         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
858
859         /* Free it */
860         irq_free_virt(virq, 1);
861 }
862 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
863
864 unsigned int irq_find_mapping(struct irq_host *host,
865                               irq_hw_number_t hwirq)
866 {
867         unsigned int i;
868         unsigned int hint = hwirq % irq_virq_count;
869
870         /* Look for default host if nececssary */
871         if (host == NULL)
872                 host = irq_default_host;
873         if (host == NULL)
874                 return NO_IRQ;
875
876         /* legacy -> bail early */
877         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
878                 return hwirq;
879
880         /* Slow path does a linear search of the map */
881         if (hint < NUM_ISA_INTERRUPTS)
882                 hint = NUM_ISA_INTERRUPTS;
883         i = hint;
884         do  {
885                 if (irq_map[i].host == host &&
886                     irq_map[i].hwirq == hwirq)
887                         return i;
888                 i++;
889                 if (i >= irq_virq_count)
890                         i = NUM_ISA_INTERRUPTS;
891         } while(i != hint);
892         return NO_IRQ;
893 }
894 EXPORT_SYMBOL_GPL(irq_find_mapping);
895
896
897 unsigned int irq_radix_revmap(struct irq_host *host,
898                               irq_hw_number_t hwirq)
899 {
900         struct radix_tree_root *tree;
901         struct irq_map_entry *ptr;
902         unsigned int virq;
903         unsigned long flags;
904
905         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
906
907         /* Check if the radix tree exist yet. We test the value of
908          * the gfp_mask for that. Sneaky but saves another int in the
909          * structure. If not, we fallback to slow mode
910          */
911         tree = &host->revmap_data.tree;
912         if (tree->gfp_mask == 0)
913                 return irq_find_mapping(host, hwirq);
914
915         /* Now try to resolve */
916         irq_radix_rdlock(&flags);
917         ptr = radix_tree_lookup(tree, hwirq);
918         irq_radix_rdunlock(flags);
919
920         /* Found it, return */
921         if (ptr) {
922                 virq = ptr - irq_map;
923                 return virq;
924         }
925
926         /* If not there, try to insert it */
927         virq = irq_find_mapping(host, hwirq);
928         if (virq != NO_IRQ) {
929                 irq_radix_wrlock(&flags);
930                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
931                 irq_radix_wrunlock(flags);
932         }
933         return virq;
934 }
935
936 unsigned int irq_linear_revmap(struct irq_host *host,
937                                irq_hw_number_t hwirq)
938 {
939         unsigned int *revmap;
940
941         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
942
943         /* Check revmap bounds */
944         if (unlikely(hwirq >= host->revmap_data.linear.size))
945                 return irq_find_mapping(host, hwirq);
946
947         /* Check if revmap was allocated */
948         revmap = host->revmap_data.linear.revmap;
949         if (unlikely(revmap == NULL))
950                 return irq_find_mapping(host, hwirq);
951
952         /* Fill up revmap with slow path if no mapping found */
953         if (unlikely(revmap[hwirq] == NO_IRQ))
954                 revmap[hwirq] = irq_find_mapping(host, hwirq);
955
956         return revmap[hwirq];
957 }
958
959 unsigned int irq_alloc_virt(struct irq_host *host,
960                             unsigned int count,
961                             unsigned int hint)
962 {
963         unsigned long flags;
964         unsigned int i, j, found = NO_IRQ;
965
966         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
967                 return NO_IRQ;
968
969         spin_lock_irqsave(&irq_big_lock, flags);
970
971         /* Use hint for 1 interrupt if any */
972         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
973             hint < irq_virq_count && irq_map[hint].host == NULL) {
974                 found = hint;
975                 goto hint_found;
976         }
977
978         /* Look for count consecutive numbers in the allocatable
979          * (non-legacy) space
980          */
981         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
982                 if (irq_map[i].host != NULL)
983                         j = 0;
984                 else
985                         j++;
986
987                 if (j == count) {
988                         found = i - count + 1;
989                         break;
990                 }
991         }
992         if (found == NO_IRQ) {
993                 spin_unlock_irqrestore(&irq_big_lock, flags);
994                 return NO_IRQ;
995         }
996  hint_found:
997         for (i = found; i < (found + count); i++) {
998                 irq_map[i].hwirq = host->inval_irq;
999                 smp_wmb();
1000                 irq_map[i].host = host;
1001         }
1002         spin_unlock_irqrestore(&irq_big_lock, flags);
1003         return found;
1004 }
1005
1006 void irq_free_virt(unsigned int virq, unsigned int count)
1007 {
1008         unsigned long flags;
1009         unsigned int i;
1010
1011         WARN_ON (virq < NUM_ISA_INTERRUPTS);
1012         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
1013
1014         spin_lock_irqsave(&irq_big_lock, flags);
1015         for (i = virq; i < (virq + count); i++) {
1016                 struct irq_host *host;
1017
1018                 if (i < NUM_ISA_INTERRUPTS ||
1019                     (virq + count) > irq_virq_count)
1020                         continue;
1021
1022                 host = irq_map[i].host;
1023                 irq_map[i].hwirq = host->inval_irq;
1024                 smp_wmb();
1025                 irq_map[i].host = NULL;
1026         }
1027         spin_unlock_irqrestore(&irq_big_lock, flags);
1028 }
1029
1030 void irq_early_init(void)
1031 {
1032         unsigned int i;
1033
1034         for (i = 0; i < NR_IRQS; i++)
1035                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
1036 }
1037
1038 /* We need to create the radix trees late */
1039 static int irq_late_init(void)
1040 {
1041         struct irq_host *h;
1042         unsigned long flags;
1043
1044         irq_radix_wrlock(&flags);
1045         list_for_each_entry(h, &irq_hosts, link) {
1046                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
1047                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
1048         }
1049         irq_radix_wrunlock(flags);
1050
1051         return 0;
1052 }
1053 arch_initcall(irq_late_init);
1054
1055 #ifdef CONFIG_VIRQ_DEBUG
1056 static int virq_debug_show(struct seq_file *m, void *private)
1057 {
1058         unsigned long flags;
1059         irq_desc_t *desc;
1060         const char *p;
1061         char none[] = "none";
1062         int i;
1063
1064         seq_printf(m, "%-5s  %-7s  %-15s  %s\n", "virq", "hwirq",
1065                       "chip name", "host name");
1066
1067         for (i = 1; i < NR_IRQS; i++) {
1068                 desc = get_irq_desc(i);
1069                 spin_lock_irqsave(&desc->lock, flags);
1070
1071                 if (desc->action && desc->action->handler) {
1072                         seq_printf(m, "%5d  ", i);
1073                         seq_printf(m, "0x%05lx  ", virq_to_hw(i));
1074
1075                         if (desc->chip && desc->chip->typename)
1076                                 p = desc->chip->typename;
1077                         else
1078                                 p = none;
1079                         seq_printf(m, "%-15s  ", p);
1080
1081                         if (irq_map[i].host && irq_map[i].host->of_node)
1082                                 p = irq_map[i].host->of_node->full_name;
1083                         else
1084                                 p = none;
1085                         seq_printf(m, "%s\n", p);
1086                 }
1087
1088                 spin_unlock_irqrestore(&desc->lock, flags);
1089         }
1090
1091         return 0;
1092 }
1093
1094 static int virq_debug_open(struct inode *inode, struct file *file)
1095 {
1096         return single_open(file, virq_debug_show, inode->i_private);
1097 }
1098
1099 static const struct file_operations virq_debug_fops = {
1100         .open = virq_debug_open,
1101         .read = seq_read,
1102         .llseek = seq_lseek,
1103         .release = single_release,
1104 };
1105
1106 static int __init irq_debugfs_init(void)
1107 {
1108         if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
1109                                  NULL, &virq_debug_fops) == NULL)
1110                 return -ENOMEM;
1111
1112         return 0;
1113 }
1114 __initcall(irq_debugfs_init);
1115 #endif /* CONFIG_VIRQ_DEBUG */
1116
1117 #endif /* CONFIG_PPC_MERGE */
1118
1119 #ifdef CONFIG_PPC64
1120 static int __init setup_noirqdistrib(char *str)
1121 {
1122         distribute_irqs = 0;
1123         return 1;
1124 }
1125
1126 __setup("noirqdistrib", setup_noirqdistrib);
1127 #endif /* CONFIG_PPC64 */