Merge branch 'upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/linville...
[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 #include <linux/pci.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 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 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 void 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                 return;
147         }
148
149         /*
150          * if (get_paca()->hard_enabled) return;
151          * But again we need to take care that gcc gets hard_enabled directly
152          * via r13, not choose to use an intermediate register, lest we're
153          * preempted to a different cpu in between the two instructions.
154          */
155         if (get_hard_enabled())
156                 return;
157
158         /*
159          * Need to hard-enable interrupts here.  Since currently disabled,
160          * no need to take further asm precautions against preemption; but
161          * use local_paca instead of get_paca() to avoid preemption checking.
162          */
163         local_paca->hard_enabled = en;
164         if ((int)mfspr(SPRN_DEC) < 0)
165                 mtspr(SPRN_DEC, 1);
166
167         /*
168          * Force the delivery of pending soft-disabled interrupts on PS3.
169          * Any HV call will have this side effect.
170          */
171         if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
172                 u64 tmp;
173                 lv1_get_version_info(&tmp);
174         }
175
176         hard_irq_enable();
177 }
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                         if (handler == NULL)
311                                 handler = &__do_IRQ;
312                         irqtp->task = curtp->task;
313                         irqtp->flags = 0;
314                         call_handle_irq(irq, desc, irqtp, handler);
315                         irqtp->task = NULL;
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         ppc_md.init_IRQ();
341 #ifdef CONFIG_PPC64
342         irq_ctx_init();
343 #endif
344 }
345
346
347 #ifdef CONFIG_IRQSTACKS
348 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
349 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
350
351 void irq_ctx_init(void)
352 {
353         struct thread_info *tp;
354         int i;
355
356         for_each_possible_cpu(i) {
357                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
358                 tp = softirq_ctx[i];
359                 tp->cpu = i;
360                 tp->preempt_count = SOFTIRQ_OFFSET;
361
362                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
363                 tp = hardirq_ctx[i];
364                 tp->cpu = i;
365                 tp->preempt_count = HARDIRQ_OFFSET;
366         }
367 }
368
369 static inline void do_softirq_onstack(void)
370 {
371         struct thread_info *curtp, *irqtp;
372
373         curtp = current_thread_info();
374         irqtp = softirq_ctx[smp_processor_id()];
375         irqtp->task = curtp->task;
376         call_do_softirq(irqtp);
377         irqtp->task = NULL;
378 }
379
380 #else
381 #define do_softirq_onstack()    __do_softirq()
382 #endif /* CONFIG_IRQSTACKS */
383
384 void do_softirq(void)
385 {
386         unsigned long flags;
387
388         if (in_interrupt())
389                 return;
390
391         local_irq_save(flags);
392
393         if (local_softirq_pending())
394                 do_softirq_onstack();
395
396         local_irq_restore(flags);
397 }
398 EXPORT_SYMBOL(do_softirq);
399
400
401 /*
402  * IRQ controller and virtual interrupts
403  */
404
405 #ifdef CONFIG_PPC_MERGE
406
407 static LIST_HEAD(irq_hosts);
408 static DEFINE_SPINLOCK(irq_big_lock);
409 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
410 static unsigned int irq_radix_writer;
411 struct irq_map_entry irq_map[NR_IRQS];
412 static unsigned int irq_virq_count = NR_IRQS;
413 static struct irq_host *irq_default_host;
414
415 struct irq_host *irq_alloc_host(unsigned int revmap_type,
416                                 unsigned int revmap_arg,
417                                 struct irq_host_ops *ops,
418                                 irq_hw_number_t inval_irq)
419 {
420         struct irq_host *host;
421         unsigned int size = sizeof(struct irq_host);
422         unsigned int i;
423         unsigned int *rmap;
424         unsigned long flags;
425
426         /* Allocate structure and revmap table if using linear mapping */
427         if (revmap_type == IRQ_HOST_MAP_LINEAR)
428                 size += revmap_arg * sizeof(unsigned int);
429         if (mem_init_done)
430                 host = kzalloc(size, GFP_KERNEL);
431         else {
432                 host = alloc_bootmem(size);
433                 if (host)
434                         memset(host, 0, size);
435         }
436         if (host == NULL)
437                 return NULL;
438
439         /* Fill structure */
440         host->revmap_type = revmap_type;
441         host->inval_irq = inval_irq;
442         host->ops = ops;
443
444         spin_lock_irqsave(&irq_big_lock, flags);
445
446         /* If it's a legacy controller, check for duplicates and
447          * mark it as allocated (we use irq 0 host pointer for that
448          */
449         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
450                 if (irq_map[0].host != NULL) {
451                         spin_unlock_irqrestore(&irq_big_lock, flags);
452                         /* If we are early boot, we can't free the structure,
453                          * too bad...
454                          * this will be fixed once slab is made available early
455                          * instead of the current cruft
456                          */
457                         if (mem_init_done)
458                                 kfree(host);
459                         return NULL;
460                 }
461                 irq_map[0].host = host;
462         }
463
464         list_add(&host->link, &irq_hosts);
465         spin_unlock_irqrestore(&irq_big_lock, flags);
466
467         /* Additional setups per revmap type */
468         switch(revmap_type) {
469         case IRQ_HOST_MAP_LEGACY:
470                 /* 0 is always the invalid number for legacy */
471                 host->inval_irq = 0;
472                 /* setup us as the host for all legacy interrupts */
473                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
474                         irq_map[i].hwirq = 0;
475                         smp_wmb();
476                         irq_map[i].host = host;
477                         smp_wmb();
478
479                         /* Clear norequest flags */
480                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
481
482                         /* Legacy flags are left to default at this point,
483                          * one can then use irq_create_mapping() to
484                          * explicitely change them
485                          */
486                         ops->map(host, i, i);
487                 }
488                 break;
489         case IRQ_HOST_MAP_LINEAR:
490                 rmap = (unsigned int *)(host + 1);
491                 for (i = 0; i < revmap_arg; i++)
492                         rmap[i] = IRQ_NONE;
493                 host->revmap_data.linear.size = revmap_arg;
494                 smp_wmb();
495                 host->revmap_data.linear.revmap = rmap;
496                 break;
497         default:
498                 break;
499         }
500
501         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
502
503         return host;
504 }
505
506 struct irq_host *irq_find_host(struct device_node *node)
507 {
508         struct irq_host *h, *found = NULL;
509         unsigned long flags;
510
511         /* We might want to match the legacy controller last since
512          * it might potentially be set to match all interrupts in
513          * the absence of a device node. This isn't a problem so far
514          * yet though...
515          */
516         spin_lock_irqsave(&irq_big_lock, flags);
517         list_for_each_entry(h, &irq_hosts, link)
518                 if (h->ops->match == NULL || h->ops->match(h, node)) {
519                         found = h;
520                         break;
521                 }
522         spin_unlock_irqrestore(&irq_big_lock, flags);
523         return found;
524 }
525 EXPORT_SYMBOL_GPL(irq_find_host);
526
527 void irq_set_default_host(struct irq_host *host)
528 {
529         pr_debug("irq: Default host set to @0x%p\n", host);
530
531         irq_default_host = host;
532 }
533
534 void irq_set_virq_count(unsigned int count)
535 {
536         pr_debug("irq: Trying to set virq count to %d\n", count);
537
538         BUG_ON(count < NUM_ISA_INTERRUPTS);
539         if (count < NR_IRQS)
540                 irq_virq_count = count;
541 }
542
543 /* radix tree not lockless safe ! we use a brlock-type mecanism
544  * for now, until we can use a lockless radix tree
545  */
546 static void irq_radix_wrlock(unsigned long *flags)
547 {
548         unsigned int cpu, ok;
549
550         spin_lock_irqsave(&irq_big_lock, *flags);
551         irq_radix_writer = 1;
552         smp_mb();
553         do {
554                 barrier();
555                 ok = 1;
556                 for_each_possible_cpu(cpu) {
557                         if (per_cpu(irq_radix_reader, cpu)) {
558                                 ok = 0;
559                                 break;
560                         }
561                 }
562                 if (!ok)
563                         cpu_relax();
564         } while(!ok);
565 }
566
567 static void irq_radix_wrunlock(unsigned long flags)
568 {
569         smp_wmb();
570         irq_radix_writer = 0;
571         spin_unlock_irqrestore(&irq_big_lock, flags);
572 }
573
574 static void irq_radix_rdlock(unsigned long *flags)
575 {
576         local_irq_save(*flags);
577         __get_cpu_var(irq_radix_reader) = 1;
578         smp_mb();
579         if (likely(irq_radix_writer == 0))
580                 return;
581         __get_cpu_var(irq_radix_reader) = 0;
582         smp_wmb();
583         spin_lock(&irq_big_lock);
584         __get_cpu_var(irq_radix_reader) = 1;
585         spin_unlock(&irq_big_lock);
586 }
587
588 static void irq_radix_rdunlock(unsigned long flags)
589 {
590         __get_cpu_var(irq_radix_reader) = 0;
591         local_irq_restore(flags);
592 }
593
594
595 unsigned int irq_create_mapping(struct irq_host *host,
596                                 irq_hw_number_t hwirq)
597 {
598         unsigned int virq, hint;
599
600         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
601
602         /* Look for default host if nececssary */
603         if (host == NULL)
604                 host = irq_default_host;
605         if (host == NULL) {
606                 printk(KERN_WARNING "irq_create_mapping called for"
607                        " NULL host, hwirq=%lx\n", hwirq);
608                 WARN_ON(1);
609                 return NO_IRQ;
610         }
611         pr_debug("irq: -> using host @%p\n", host);
612
613         /* Check if mapping already exist, if it does, call
614          * host->ops->map() to update the flags
615          */
616         virq = irq_find_mapping(host, hwirq);
617         if (virq != IRQ_NONE) {
618                 if (host->ops->remap)
619                         host->ops->remap(host, virq, hwirq);
620                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
621                 return virq;
622         }
623
624         /* Get a virtual interrupt number */
625         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
626                 /* Handle legacy */
627                 virq = (unsigned int)hwirq;
628                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
629                         return NO_IRQ;
630                 return virq;
631         } else {
632                 /* Allocate a virtual interrupt number */
633                 hint = hwirq % irq_virq_count;
634                 virq = irq_alloc_virt(host, 1, hint);
635                 if (virq == NO_IRQ) {
636                         pr_debug("irq: -> virq allocation failed\n");
637                         return NO_IRQ;
638                 }
639         }
640         pr_debug("irq: -> obtained virq %d\n", virq);
641
642         /* Clear IRQ_NOREQUEST flag */
643         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
644
645         /* map it */
646         smp_wmb();
647         irq_map[virq].hwirq = hwirq;
648         smp_mb();
649         if (host->ops->map(host, virq, hwirq)) {
650                 pr_debug("irq: -> mapping failed, freeing\n");
651                 irq_free_virt(virq, 1);
652                 return NO_IRQ;
653         }
654         return virq;
655 }
656 EXPORT_SYMBOL_GPL(irq_create_mapping);
657
658 unsigned int irq_create_of_mapping(struct device_node *controller,
659                                    u32 *intspec, unsigned int intsize)
660 {
661         struct irq_host *host;
662         irq_hw_number_t hwirq;
663         unsigned int type = IRQ_TYPE_NONE;
664         unsigned int virq;
665
666         if (controller == NULL)
667                 host = irq_default_host;
668         else
669                 host = irq_find_host(controller);
670         if (host == NULL) {
671                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
672                        controller->full_name);
673                 return NO_IRQ;
674         }
675
676         /* If host has no translation, then we assume interrupt line */
677         if (host->ops->xlate == NULL)
678                 hwirq = intspec[0];
679         else {
680                 if (host->ops->xlate(host, controller, intspec, intsize,
681                                      &hwirq, &type))
682                         return NO_IRQ;
683         }
684
685         /* Create mapping */
686         virq = irq_create_mapping(host, hwirq);
687         if (virq == NO_IRQ)
688                 return virq;
689
690         /* Set type if specified and different than the current one */
691         if (type != IRQ_TYPE_NONE &&
692             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
693                 set_irq_type(virq, type);
694         return virq;
695 }
696 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
697
698 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
699 {
700         struct of_irq oirq;
701
702         if (of_irq_map_one(dev, index, &oirq))
703                 return NO_IRQ;
704
705         return irq_create_of_mapping(oirq.controller, oirq.specifier,
706                                      oirq.size);
707 }
708 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
709
710 void irq_dispose_mapping(unsigned int virq)
711 {
712         struct irq_host *host;
713         irq_hw_number_t hwirq;
714         unsigned long flags;
715
716         if (virq == NO_IRQ)
717                 return;
718
719         host = irq_map[virq].host;
720         WARN_ON (host == NULL);
721         if (host == NULL)
722                 return;
723
724         /* Never unmap legacy interrupts */
725         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
726                 return;
727
728         /* remove chip and handler */
729         set_irq_chip_and_handler(virq, NULL, NULL);
730
731         /* Make sure it's completed */
732         synchronize_irq(virq);
733
734         /* Tell the PIC about it */
735         if (host->ops->unmap)
736                 host->ops->unmap(host, virq);
737         smp_mb();
738
739         /* Clear reverse map */
740         hwirq = irq_map[virq].hwirq;
741         switch(host->revmap_type) {
742         case IRQ_HOST_MAP_LINEAR:
743                 if (hwirq < host->revmap_data.linear.size)
744                         host->revmap_data.linear.revmap[hwirq] = IRQ_NONE;
745                 break;
746         case IRQ_HOST_MAP_TREE:
747                 /* Check if radix tree allocated yet */
748                 if (host->revmap_data.tree.gfp_mask == 0)
749                         break;
750                 irq_radix_wrlock(&flags);
751                 radix_tree_delete(&host->revmap_data.tree, hwirq);
752                 irq_radix_wrunlock(flags);
753                 break;
754         }
755
756         /* Destroy map */
757         smp_mb();
758         irq_map[virq].hwirq = host->inval_irq;
759
760         /* Set some flags */
761         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
762
763         /* Free it */
764         irq_free_virt(virq, 1);
765 }
766 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
767
768 unsigned int irq_find_mapping(struct irq_host *host,
769                               irq_hw_number_t hwirq)
770 {
771         unsigned int i;
772         unsigned int hint = hwirq % irq_virq_count;
773
774         /* Look for default host if nececssary */
775         if (host == NULL)
776                 host = irq_default_host;
777         if (host == NULL)
778                 return NO_IRQ;
779
780         /* legacy -> bail early */
781         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
782                 return hwirq;
783
784         /* Slow path does a linear search of the map */
785         if (hint < NUM_ISA_INTERRUPTS)
786                 hint = NUM_ISA_INTERRUPTS;
787         i = hint;
788         do  {
789                 if (irq_map[i].host == host &&
790                     irq_map[i].hwirq == hwirq)
791                         return i;
792                 i++;
793                 if (i >= irq_virq_count)
794                         i = NUM_ISA_INTERRUPTS;
795         } while(i != hint);
796         return NO_IRQ;
797 }
798 EXPORT_SYMBOL_GPL(irq_find_mapping);
799
800
801 unsigned int irq_radix_revmap(struct irq_host *host,
802                               irq_hw_number_t hwirq)
803 {
804         struct radix_tree_root *tree;
805         struct irq_map_entry *ptr;
806         unsigned int virq;
807         unsigned long flags;
808
809         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
810
811         /* Check if the radix tree exist yet. We test the value of
812          * the gfp_mask for that. Sneaky but saves another int in the
813          * structure. If not, we fallback to slow mode
814          */
815         tree = &host->revmap_data.tree;
816         if (tree->gfp_mask == 0)
817                 return irq_find_mapping(host, hwirq);
818
819         /* Now try to resolve */
820         irq_radix_rdlock(&flags);
821         ptr = radix_tree_lookup(tree, hwirq);
822         irq_radix_rdunlock(flags);
823
824         /* Found it, return */
825         if (ptr) {
826                 virq = ptr - irq_map;
827                 return virq;
828         }
829
830         /* If not there, try to insert it */
831         virq = irq_find_mapping(host, hwirq);
832         if (virq != NO_IRQ) {
833                 irq_radix_wrlock(&flags);
834                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
835                 irq_radix_wrunlock(flags);
836         }
837         return virq;
838 }
839
840 unsigned int irq_linear_revmap(struct irq_host *host,
841                                irq_hw_number_t hwirq)
842 {
843         unsigned int *revmap;
844
845         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
846
847         /* Check revmap bounds */
848         if (unlikely(hwirq >= host->revmap_data.linear.size))
849                 return irq_find_mapping(host, hwirq);
850
851         /* Check if revmap was allocated */
852         revmap = host->revmap_data.linear.revmap;
853         if (unlikely(revmap == NULL))
854                 return irq_find_mapping(host, hwirq);
855
856         /* Fill up revmap with slow path if no mapping found */
857         if (unlikely(revmap[hwirq] == NO_IRQ))
858                 revmap[hwirq] = irq_find_mapping(host, hwirq);
859
860         return revmap[hwirq];
861 }
862
863 unsigned int irq_alloc_virt(struct irq_host *host,
864                             unsigned int count,
865                             unsigned int hint)
866 {
867         unsigned long flags;
868         unsigned int i, j, found = NO_IRQ;
869
870         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
871                 return NO_IRQ;
872
873         spin_lock_irqsave(&irq_big_lock, flags);
874
875         /* Use hint for 1 interrupt if any */
876         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
877             hint < irq_virq_count && irq_map[hint].host == NULL) {
878                 found = hint;
879                 goto hint_found;
880         }
881
882         /* Look for count consecutive numbers in the allocatable
883          * (non-legacy) space
884          */
885         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
886                 if (irq_map[i].host != NULL)
887                         j = 0;
888                 else
889                         j++;
890
891                 if (j == count) {
892                         found = i - count + 1;
893                         break;
894                 }
895         }
896         if (found == NO_IRQ) {
897                 spin_unlock_irqrestore(&irq_big_lock, flags);
898                 return NO_IRQ;
899         }
900  hint_found:
901         for (i = found; i < (found + count); i++) {
902                 irq_map[i].hwirq = host->inval_irq;
903                 smp_wmb();
904                 irq_map[i].host = host;
905         }
906         spin_unlock_irqrestore(&irq_big_lock, flags);
907         return found;
908 }
909
910 void irq_free_virt(unsigned int virq, unsigned int count)
911 {
912         unsigned long flags;
913         unsigned int i;
914
915         WARN_ON (virq < NUM_ISA_INTERRUPTS);
916         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
917
918         spin_lock_irqsave(&irq_big_lock, flags);
919         for (i = virq; i < (virq + count); i++) {
920                 struct irq_host *host;
921
922                 if (i < NUM_ISA_INTERRUPTS ||
923                     (virq + count) > irq_virq_count)
924                         continue;
925
926                 host = irq_map[i].host;
927                 irq_map[i].hwirq = host->inval_irq;
928                 smp_wmb();
929                 irq_map[i].host = NULL;
930         }
931         spin_unlock_irqrestore(&irq_big_lock, flags);
932 }
933
934 void irq_early_init(void)
935 {
936         unsigned int i;
937
938         for (i = 0; i < NR_IRQS; i++)
939                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
940 }
941
942 /* We need to create the radix trees late */
943 static int irq_late_init(void)
944 {
945         struct irq_host *h;
946         unsigned long flags;
947
948         irq_radix_wrlock(&flags);
949         list_for_each_entry(h, &irq_hosts, link) {
950                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
951                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
952         }
953         irq_radix_wrunlock(flags);
954
955         return 0;
956 }
957 arch_initcall(irq_late_init);
958
959 #endif /* CONFIG_PPC_MERGE */
960
961 #ifdef CONFIG_PPC64
962 static int __init setup_noirqdistrib(char *str)
963 {
964         distribute_irqs = 0;
965         return 1;
966 }
967
968 __setup("noirqdistrib", setup_noirqdistrib);
969 #endif /* CONFIG_PPC64 */