aboutsummaryrefslogblamecommitdiffstats
path: root/arch/sparc64/kernel/irq.c
blob: 4dcb8af94090cfc490da271877561d988b3a2aea (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758





















































































































































































































































































































































































































































































































































































































































































































































































                                                                                          
                               

























































































































































































































































                                                                                     
            

                                          
                                        































































































































































































































































                                                                                      
/* $Id: irq.c,v 1.114 2002/01/11 08:45:38 davem Exp $
 * irq.c: UltraSparc IRQ handling/init/registry.
 *
 * Copyright (C) 1997  David S. Miller  (davem@caip.rutgers.edu)
 * Copyright (C) 1998  Eddie C. Dost    (ecd@skynet.be)
 * Copyright (C) 1998  Jakub Jelinek    (jj@ultra.linux.cz)
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>

#include <asm/ptrace.h>
#include <asm/processor.h>
#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/irq.h>
#include <asm/sbus.h>
#include <asm/iommu.h>
#include <asm/upa.h>
#include <asm/oplib.h>
#include <asm/timer.h>
#include <asm/smp.h>
#include <asm/starfire.h>
#include <asm/uaccess.h>
#include <asm/cache.h>
#include <asm/cpudata.h>

#ifdef CONFIG_SMP
static void distribute_irqs(void);
#endif

/* UPA nodes send interrupt packet to UltraSparc with first data reg
 * value low 5 (7 on Starfire) bits holding the IRQ identifier being
 * delivered.  We must translate this into a non-vector IRQ so we can
 * set the softint on this cpu.
 *
 * To make processing these packets efficient and race free we use
 * an array of irq buckets below.  The interrupt vector handler in
 * entry.S feeds incoming packets into per-cpu pil-indexed lists.
 * The IVEC handler does not need to act atomically, the PIL dispatch
 * code uses CAS to get an atomic snapshot of the list and clear it
 * at the same time.
 */

struct ino_bucket ivector_table[NUM_IVECS] __attribute__ ((aligned (SMP_CACHE_BYTES)));

/* This has to be in the main kernel image, it cannot be
 * turned into per-cpu data.  The reason is that the main
 * kernel image is locked into the TLB and this structure
 * is accessed from the vectored interrupt trap handler.  If
 * access to this structure takes a TLB miss it could cause
 * the 5-level sparc v9 trap stack to overflow.
 */
struct irq_work_struct {
	unsigned int	irq_worklists[16];
};
struct irq_work_struct __irq_work[NR_CPUS];
#define irq_work(__cpu, __pil)	&(__irq_work[(__cpu)].irq_worklists[(__pil)])

#ifdef CONFIG_PCI
/* This is a table of physical addresses used to deal with IBF_DMA_SYNC.
 * It is used for PCI only to synchronize DMA transfers with IRQ delivery
 * for devices behind busses other than APB on Sabre systems.
 *
 * Currently these physical addresses are just config space accesses
 * to the command register for that device.
 */
unsigned long pci_dma_wsync;
unsigned long dma_sync_reg_table[256];
unsigned char dma_sync_reg_table_entry = 0;
#endif

/* This is based upon code in the 32-bit Sparc kernel written mostly by
 * David Redman (djhr@tadpole.co.uk).
 */
#define MAX_STATIC_ALLOC	4
static struct irqaction static_irqaction[MAX_STATIC_ALLOC];
static int static_irq_count;

/* This is exported so that fast IRQ handlers can get at it... -DaveM */
struct irqaction *irq_action[NR_IRQS+1] = {
	  NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL,
	  NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL
};

/* This only synchronizes entities which modify IRQ handler
 * state and some selected user-level spots that want to
 * read things in the table.  IRQ handler processing orders
 * its' accesses such that no locking is needed.
 */
static DEFINE_SPINLOCK(irq_action_lock);

static void register_irq_proc (unsigned int irq);

/*
 * Upper 2b of irqaction->flags holds the ino.
 * irqaction->mask holds the smp affinity information.
 */
#define put_ino_in_irqaction(action, irq) \
	action->flags &= 0xffffffffffffUL; \
	if (__bucket(irq) == &pil0_dummy_bucket) \
		action->flags |= 0xdeadUL << 48;  \
	else \
		action->flags |= __irq_ino(irq) << 48;
#define get_ino_in_irqaction(action)	(action->flags >> 48)

#define put_smpaff_in_irqaction(action, smpaff)	(action)->mask = (smpaff)
#define get_smpaff_in_irqaction(action) 	((action)->mask)

int show_interrupts(struct seq_file *p, void *v)
{
	unsigned long flags;
	int i = *(loff_t *) v;
	struct irqaction *action;
#ifdef CONFIG_SMP
	int j;
#endif

	spin_lock_irqsave(&irq_action_lock, flags);
	if (i <= NR_IRQS) {
		if (!(action = *(i + irq_action)))
			goto out_unlock;
		seq_printf(p, "%3d: ", i);
#ifndef CONFIG_SMP
		seq_printf(p, "%10u ", kstat_irqs(i));
#else
		for (j = 0; j < NR_CPUS; j++) {
			if (!cpu_online(j))
				continue;
			seq_printf(p, "%10u ",
				   kstat_cpu(j).irqs[i]);
		}
#endif
		seq_printf(p, " %s:%lx", action->name,
			   get_ino_in_irqaction(action));
		for (action = action->next; action; action = action->next) {
			seq_printf(p, ", %s:%lx", action->name,
				   get_ino_in_irqaction(action));
		}
		seq_putc(p, '\n');
	}
out_unlock:
	spin_unlock_irqrestore(&irq_action_lock, flags);

	return 0;
}

/* Now these are always passed a true fully specified sun4u INO. */
void enable_irq(unsigned int irq)
{
	struct ino_bucket *bucket = __bucket(irq);
	unsigned long imap;
	unsigned long tid;

	imap = bucket->imap;
	if (imap == 0UL)
		return;

	preempt_disable();

	if (tlb_type == cheetah || tlb_type == cheetah_plus) {
		unsigned long ver;

		__asm__ ("rdpr %%ver, %0" : "=r" (ver));
		if ((ver >> 32) == 0x003e0016) {
			/* We set it to our JBUS ID. */
			__asm__ __volatile__("ldxa [%%g0] %1, %0"
					     : "=r" (tid)
					     : "i" (ASI_JBUS_CONFIG));
			tid = ((tid & (0x1fUL<<17)) << 9);
			tid &= IMAP_TID_JBUS;
		} else {
			/* We set it to our Safari AID. */
			__asm__ __volatile__("ldxa [%%g0] %1, %0"
					     : "=r" (tid)
					     : "i" (ASI_SAFARI_CONFIG));
			tid = ((tid & (0x3ffUL<<17)) << 9);
			tid &= IMAP_AID_SAFARI;
		}
	} else if (this_is_starfire == 0) {
		/* We set it to our UPA MID. */
		__asm__ __volatile__("ldxa [%%g0] %1, %0"
				     : "=r" (tid)
				     : "i" (ASI_UPA_CONFIG));
		tid = ((tid & UPA_CONFIG_MID) << 9);
		tid &= IMAP_TID_UPA;
	} else {
		tid = (starfire_translate(imap, smp_processor_id()) << 26);
		tid &= IMAP_TID_UPA;
	}

	/* NOTE NOTE NOTE, IGN and INO are read-only, IGN is a product
	 * of this SYSIO's preconfigured IGN in the SYSIO Control
	 * Register, the hardware just mirrors that value here.
	 * However for Graphics and UPA Slave devices the full
	 * IMAP_INR field can be set by the programmer here.
	 *
	 * Things like FFB can now be handled via the new IRQ mechanism.
	 */
	upa_writel(tid | IMAP_VALID, imap);

	preempt_enable();
}

/* This now gets passed true ino's as well. */
void disable_irq(unsigned int irq)
{
	struct ino_bucket *bucket = __bucket(irq);
	unsigned long imap;

	imap = bucket->imap;
	if (imap != 0UL) {
		u32 tmp;

		/* NOTE: We do not want to futz with the IRQ clear registers
		 *       and move the state to IDLE, the SCSI code does call
		 *       disable_irq() to assure atomicity in the queue cmd
		 *       SCSI adapter driver code.  Thus we'd lose interrupts.
		 */
		tmp = upa_readl(imap);
		tmp &= ~IMAP_VALID;
		upa_writel(tmp, imap);
	}
}

/* The timer is the one "weird" interrupt which is generated by
 * the CPU %tick register and not by some normal vectored interrupt
 * source.  To handle this special case, we use this dummy INO bucket.
 */
static struct ino_bucket pil0_dummy_bucket = {
	0,	/* irq_chain */
	0,	/* pil */
	0,	/* pending */
	0,	/* flags */
	0,	/* __unused */
	NULL,	/* irq_info */
	0UL,	/* iclr */
	0UL,	/* imap */
};

unsigned int build_irq(int pil, int inofixup, unsigned long iclr, unsigned long imap)
{
	struct ino_bucket *bucket;
	int ino;

	if (pil == 0) {
		if (iclr != 0UL || imap != 0UL) {
			prom_printf("Invalid dummy bucket for PIL0 (%lx:%lx)\n",
				    iclr, imap);
			prom_halt();
		}
		return __irq(&pil0_dummy_bucket);
	}

	/* RULE: Both must be specified in all other cases. */
	if (iclr == 0UL || imap == 0UL) {
		prom_printf("Invalid build_irq %d %d %016lx %016lx\n",
			    pil, inofixup, iclr, imap);
		prom_halt();
	}
	
	ino = (upa_readl(imap) & (IMAP_IGN | IMAP_INO)) + inofixup;
	if (ino > NUM_IVECS) {
		prom_printf("Invalid INO %04x (%d:%d:%016lx:%016lx)\n",
			    ino, pil, inofixup, iclr, imap);
		prom_halt();
	}

	/* Ok, looks good, set it up.  Don't touch the irq_chain or
	 * the pending flag.
	 */
	bucket = &ivector_table[ino];
	if ((bucket->flags & IBF_ACTIVE) ||
	    (bucket->irq_info != NULL)) {
		/* This is a gross fatal error if it happens here. */
		prom_printf("IRQ: Trying to reinit INO bucket, fatal error.\n");
		prom_printf("IRQ: Request INO %04x (%d:%d:%016lx:%016lx)\n",
			    ino, pil, inofixup, iclr, imap);
		prom_printf("IRQ: Existing (%d:%016lx:%016lx)\n",
			    bucket->pil, bucket->iclr, bucket->imap);
		prom_printf("IRQ: Cannot continue, halting...\n");
		prom_halt();
	}
	bucket->imap  = imap;
	bucket->iclr  = iclr;
	bucket->pil   = pil;
	bucket->flags = 0;

	bucket->irq_info = NULL;

	return __irq(bucket);
}

static void atomic_bucket_insert(struct ino_bucket *bucket)
{
	unsigned long pstate;
	unsigned int *ent;

	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
	__asm__ __volatile__("wrpr %0, %1, %%pstate"
			     : : "r" (pstate), "i" (PSTATE_IE));
	ent = irq_work(smp_processor_id(), bucket->pil);
	bucket->irq_chain = *ent;
	*ent = __irq(bucket);
	__asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
}

int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *),
		unsigned long irqflags, const char *name, void *dev_id)
{
	struct irqaction *action, *tmp = NULL;
	struct ino_bucket *bucket = __bucket(irq);
	unsigned long flags;
	int pending = 0;

	if ((bucket != &pil0_dummy_bucket) &&
	    (bucket < &ivector_table[0] ||
	     bucket >= &ivector_table[NUM_IVECS])) {
		unsigned int *caller;

		__asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
		printk(KERN_CRIT "request_irq: Old style IRQ registry attempt "
		       "from %p, irq %08x.\n", caller, irq);
		return -EINVAL;
	}	
	if (!handler)
	    return -EINVAL;

	if ((bucket != &pil0_dummy_bucket) && (irqflags & SA_SAMPLE_RANDOM)) {
		/*
	 	 * This function might sleep, we want to call it first,
	 	 * outside of the atomic block. In SA_STATIC_ALLOC case,
		 * random driver's kmalloc will fail, but it is safe.
		 * If already initialized, random driver will not reinit.
	 	 * Yes, this might clear the entropy pool if the wrong
	 	 * driver is attempted to be loaded, without actually
	 	 * installing a new handler, but is this really a problem,
	 	 * only the sysadmin is able to do this.
	 	 */
		rand_initialize_irq(irq);
	}

	spin_lock_irqsave(&irq_action_lock, flags);

	action = *(bucket->pil + irq_action);
	if (action) {
		if ((action->flags & SA_SHIRQ) && (irqflags & SA_SHIRQ))
			for (tmp = action; tmp->next; tmp = tmp->next)
				;
		else {
			spin_unlock_irqrestore(&irq_action_lock, flags);
			return -EBUSY;
		}
		action = NULL;		/* Or else! */
	}

	/* If this is flagged as statically allocated then we use our
	 * private struct which is never freed.
	 */
	if (irqflags & SA_STATIC_ALLOC) {
	    if (static_irq_count < MAX_STATIC_ALLOC)
		action = &static_irqaction[static_irq_count++];
	    else
		printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed "
		       "using kmalloc\n", irq, name);
	}	
	if (action == NULL)
	    action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
						 GFP_ATOMIC);
	
	if (!action) { 
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return -ENOMEM;
	}

	if (bucket == &pil0_dummy_bucket) {
		bucket->irq_info = action;
		bucket->flags |= IBF_ACTIVE;
	} else {
		if ((bucket->flags & IBF_ACTIVE) != 0) {
			void *orig = bucket->irq_info;
			void **vector = NULL;

			if ((bucket->flags & IBF_PCI) == 0) {
				printk("IRQ: Trying to share non-PCI bucket.\n");
				goto free_and_ebusy;
			}
			if ((bucket->flags & IBF_MULTI) == 0) {
				vector = kmalloc(sizeof(void *) * 4, GFP_ATOMIC);
				if (vector == NULL)
					goto free_and_enomem;

				/* We might have slept. */
				if ((bucket->flags & IBF_MULTI) != 0) {
					int ent;

					kfree(vector);
					vector = (void **)bucket->irq_info;
					for(ent = 0; ent < 4; ent++) {
						if (vector[ent] == NULL) {
							vector[ent] = action;
							break;
						}
					}
					if (ent == 4)
						goto free_and_ebusy;
				} else {
					vector[0] = orig;
					vector[1] = action;
					vector[2] = NULL;
					vector[3] = NULL;
					bucket->irq_info = vector;
					bucket->flags |= IBF_MULTI;
				}
			} else {
				int ent;

				vector = (void **)orig;
				for (ent = 0; ent < 4; ent++) {
					if (vector[ent] == NULL) {
						vector[ent] = action;
						break;
					}
				}
				if (ent == 4)
					goto free_and_ebusy;
			}
		} else {
			bucket->irq_info = action;
			bucket->flags |= IBF_ACTIVE;
		}
		pending = bucket->pending;
		if (pending)
			bucket->pending = 0;
	}

	action->handler = handler;
	action->flags = irqflags;
	action->name = name;
	action->next = NULL;
	action->dev_id = dev_id;
	put_ino_in_irqaction(action, irq);
	put_smpaff_in_irqaction(action, CPU_MASK_NONE);

	if (tmp)
		tmp->next = action;
	else
		*(bucket->pil + irq_action) = action;

	enable_irq(irq);

	/* We ate the IVEC already, this makes sure it does not get lost. */
	if (pending) {
		atomic_bucket_insert(bucket);
		set_softint(1 << bucket->pil);
	}
	spin_unlock_irqrestore(&irq_action_lock, flags);
	if ((bucket != &pil0_dummy_bucket) && (!(irqflags & SA_STATIC_ALLOC)))
		register_irq_proc(__irq_ino(irq));

#ifdef CONFIG_SMP
	distribute_irqs();
#endif
	return 0;

free_and_ebusy:
	kfree(action);
	spin_unlock_irqrestore(&irq_action_lock, flags);
	return -EBUSY;

free_and_enomem:
	kfree(action);
	spin_unlock_irqrestore(&irq_action_lock, flags);
	return -ENOMEM;
}

EXPORT_SYMBOL(request_irq);

void free_irq(unsigned int irq, void *dev_id)
{
	struct irqaction *action;
	struct irqaction *tmp = NULL;
	unsigned long flags;
	struct ino_bucket *bucket = __bucket(irq), *bp;

	if ((bucket != &pil0_dummy_bucket) &&
	    (bucket < &ivector_table[0] ||
	     bucket >= &ivector_table[NUM_IVECS])) {
		unsigned int *caller;

		__asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
		printk(KERN_CRIT "free_irq: Old style IRQ removal attempt "
		       "from %p, irq %08x.\n", caller, irq);
		return;
	}
	
	spin_lock_irqsave(&irq_action_lock, flags);

	action = *(bucket->pil + irq_action);
	if (!action->handler) {
		printk("Freeing free IRQ %d\n", bucket->pil);
		return;
	}
	if (dev_id) {
		for ( ; action; action = action->next) {
			if (action->dev_id == dev_id)
				break;
			tmp = action;
		}
		if (!action) {
			printk("Trying to free free shared IRQ %d\n", bucket->pil);
			spin_unlock_irqrestore(&irq_action_lock, flags);
			return;
		}
	} else if (action->flags & SA_SHIRQ) {
		printk("Trying to free shared IRQ %d with NULL device ID\n", bucket->pil);
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return;
	}

	if (action->flags & SA_STATIC_ALLOC) {
		printk("Attempt to free statically allocated IRQ %d (%s)\n",
		       bucket->pil, action->name);
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return;
	}

	if (action && tmp)
		tmp->next = action->next;
	else
		*(bucket->pil + irq_action) = action->next;

	spin_unlock_irqrestore(&irq_action_lock, flags);

	synchronize_irq(irq);

	spin_lock_irqsave(&irq_action_lock, flags);

	if (bucket != &pil0_dummy_bucket) {
		unsigned long imap = bucket->imap;
		void **vector, *orig;
		int ent;

		orig = bucket->irq_info;
		vector = (void **)orig;

		if ((bucket->flags & IBF_MULTI) != 0) {
			int other = 0;
			void *orphan = NULL;
			for (ent = 0; ent < 4; ent++) {
				if (vector[ent] == action)
					vector[ent] = NULL;
				else if (vector[ent] != NULL) {
					orphan = vector[ent];
					other++;
				}
			}

			/* Only free when no other shared irq
			 * uses this bucket.
			 */
			if (other) {
				if (other == 1) {
					/* Convert back to non-shared bucket. */
					bucket->irq_info = orphan;
					bucket->flags &= ~(IBF_MULTI);
					kfree(vector);
				}
				goto out;
			}
		} else {
			bucket->irq_info = NULL;
		}

		/* This unique interrupt source is now inactive. */
		bucket->flags &= ~IBF_ACTIVE;

		/* See if any other buckets share this bucket's IMAP
		 * and are still active.
		 */
		for (ent = 0; ent < NUM_IVECS; ent++) {
			bp = &ivector_table[ent];
			if (bp != bucket	&&
			    bp->imap == imap	&&
			    (bp->flags & IBF_ACTIVE) != 0)
				break;
		}

		/* Only disable when no other sub-irq levels of
		 * the same IMAP are active.
		 */
		if (ent == NUM_IVECS)
			disable_irq(irq);
	}

out:
	kfree(action);
	spin_unlock_irqrestore(&irq_action_lock, flags);
}

EXPORT_SYMBOL(free_irq);

#ifdef CONFIG_SMP
void synchronize_irq(unsigned int irq)
{
	struct ino_bucket *bucket = __bucket(irq);

#if 0
	/* The following is how I wish I could implement this.
	 * Unfortunately the ICLR registers are read-only, you can
	 * only write ICLR_foo values to them.  To get the current
	 * IRQ status you would need to get at the IRQ diag registers
	 * in the PCI/SBUS controller and the layout of those vary
	 * from one controller to the next, sigh... -DaveM
	 */
	unsigned long iclr = bucket->iclr;

	while (1) {
		u32 tmp = upa_readl(iclr);
		
		if (tmp == ICLR_TRANSMIT ||
		    tmp == ICLR_PENDING) {
			cpu_relax();
			continue;
		}
		break;
	}
#else
	/* So we have to do this with a INPROGRESS bit just like x86.  */
	while (bucket->flags & IBF_INPROGRESS)
		cpu_relax();
#endif
}
#endif /* CONFIG_SMP */

void catch_disabled_ivec(struct pt_regs *regs)
{
	int cpu = smp_processor_id();
	struct ino_bucket *bucket = __bucket(*irq_work(cpu, 0));

	/* We can actually see this on Ultra/PCI PCI cards, which are bridges
	 * to other devices.  Here a single IMAP enabled potentially multiple
	 * unique interrupt sources (which each do have a unique ICLR register.
	 *
	 * So what we do is just register that the IVEC arrived, when registered
	 * for real the request_irq() code will check the bit and signal
	 * a local CPU interrupt for it.
	 */
#if 0
	printk("IVEC: Spurious interrupt vector (%x) received at (%016lx)\n",
	       bucket - &ivector_table[0], regs->tpc);
#endif
	*irq_work(cpu, 0) = 0;
	bucket->pending = 1;
}

/* Tune this... */
#define FORWARD_VOLUME		12

#ifdef CONFIG_SMP

static inline void redirect_intr(int cpu, struct ino_bucket *bp)
{
	/* Ok, here is what is going on:
	 * 1) Retargeting IRQs on Starfire is very
	 *    expensive so just forget about it on them.
	 * 2) Moving around very high priority interrupts
	 *    is a losing game.
	 * 3) If the current cpu is idle, interrupts are
	 *    useful work, so keep them here.  But do not
	 *    pass to our neighbour if he is not very idle.
	 * 4) If sysadmin explicitly asks for directed intrs,
	 *    Just Do It.
	 */
	struct irqaction *ap = bp->irq_info;
	cpumask_t cpu_mask;
	unsigned int buddy, ticks;

	cpu_mask = get_smpaff_in_irqaction(ap);
	cpus_and(cpu_mask, cpu_mask, cpu_online_map);
	if (cpus_empty(cpu_mask))
		cpu_mask = cpu_online_map;

	if (this_is_starfire != 0 ||
	    bp->pil >= 10 || current->pid == 0)
		goto out;

	/* 'cpu' is the MID (ie. UPAID), calculate the MID
	 * of our buddy.
	 */
	buddy = cpu + 1;
	if (buddy >= NR_CPUS)
		buddy = 0;

	ticks = 0;
	while (!cpu_isset(buddy, cpu_mask)) {
		if (++buddy >= NR_CPUS)
			buddy = 0;
		if (++ticks > NR_CPUS) {
			put_smpaff_in_irqaction(ap, CPU_MASK_NONE);
			goto out;
		}
	}

	if (buddy == cpu)
		goto out;

	/* Voo-doo programming. */
	if (cpu_data(buddy).idle_volume < FORWARD_VOLUME)
		goto out;

	/* This just so happens to be correct on Cheetah
	 * at the moment.
	 */
	buddy <<= 26;

	/* Push it to our buddy. */
	upa_writel(buddy | IMAP_VALID, bp->imap);

out:
	return;
}

#endif

void handler_irq(int irq, struct pt_regs *regs)
{
	struct ino_bucket *bp, *nbp;
	int cpu = smp_processor_id();

#ifndef CONFIG_SMP
	/*
	 * Check for TICK_INT on level 14 softint.
	 */
	{
		unsigned long clr_mask = 1 << irq;
		unsigned long tick_mask = tick_ops->softint_mask;

		if ((irq == 14) && (get_softint() & tick_mask)) {
			irq = 0;
			clr_mask = tick_mask;
		}
		clear_softint(clr_mask);
	}
#else
	int should_forward = 0;

	clear_softint(1 << irq);
#endif

	irq_enter();
	kstat_this_cpu.irqs[irq]++;

	/* Sliiiick... */
#ifndef CONFIG_SMP
	bp = ((irq != 0) ?
	      __bucket(xchg32(irq_work(cpu, irq), 0)) :
	      &pil0_dummy_bucket);
#else
	bp = __bucket(xchg32(irq_work(cpu, irq), 0));
#endif
	for ( ; bp != NULL; bp = nbp) {
		unsigned char flags = bp->flags;
		unsigned char random = 0;

		nbp = __bucket(bp->irq_chain);
		bp->irq_chain = 0;

		bp->flags |= IBF_INPROGRESS;

		if ((flags & IBF_ACTIVE) != 0) {
#ifdef CONFIG_PCI
			if ((flags & IBF_DMA_SYNC) != 0) {
				upa_readl(dma_sync_reg_table[bp->synctab_ent]);
				upa_readq(pci_dma_wsync);
			}
#endif
			if ((flags & IBF_MULTI) == 0) {
				struct irqaction *ap = bp->irq_info;
				int ret;

				ret = ap->handler(__irq(bp), ap->dev_id, regs);
				if (ret == IRQ_HANDLED)
					random |= ap->flags;
			} else {
				void **vector = (void **)bp->irq_info;
				int ent;
				for (ent = 0; ent < 4; ent++) {
					struct irqaction *ap = vector[ent];
					if (ap != NULL) {
						int ret;

						ret = ap->handler(__irq(bp),
								  ap->dev_id,
								  regs);
						if (ret == IRQ_HANDLED)
							random |= ap->flags;
					}
				}
			}
			/* Only the dummy bucket lacks IMAP/ICLR. */
			if (bp->pil != 0) {
#ifdef CONFIG_SMP
				if (should_forward) {
					redirect_intr(cpu, bp);
					should_forward = 0;
				}
#endif
				upa_writel(ICLR_IDLE, bp->iclr);

				/* Test and add entropy */
				if (random & SA_SAMPLE_RANDOM)
					add_interrupt_randomness(irq);
			}
		} else
			bp->pending = 1;

		bp->flags &= ~IBF_INPROGRESS;
	}
	irq_exit();
}

#ifdef CONFIG_BLK_DEV_FD
extern void floppy_interrupt(int irq, void *dev_cookie, struct pt_regs *regs);

void sparc_floppy_irq(int irq, void *dev_cookie, struct pt_regs *regs)
{
	struct irqaction *action = *(irq + irq_action);
	struct ino_bucket *bucket;
	int cpu = smp_processor_id();

	irq_enter();
	kstat_this_cpu.irqs[irq]++;

	*(irq_work(cpu, irq)) = 0;
	bucket = get_ino_in_irqaction(action) + ivector_table;

	bucket->flags |= IBF_INPROGRESS;

	floppy_interrupt(irq, dev_cookie, regs);
	upa_writel(ICLR_IDLE, bucket->iclr);

	bucket->flags &= ~IBF_INPROGRESS;

	irq_exit();
}
#endif

/* The following assumes that the branch lies before the place we
 * are branching to.  This is the case for a trap vector...
 * You have been warned.
 */
#define SPARC_BRANCH(dest_addr, inst_addr) \
          (0x10800000 | ((((dest_addr)-(inst_addr))>>2)&0x3fffff))

#define SPARC_NOP (0x01000000)

static void install_fast_irq(unsigned int cpu_irq,
			     irqreturn_t (*handler)(int, void *, struct pt_regs *))
{
	extern unsigned long sparc64_ttable_tl0;
	unsigned long ttent = (unsigned long) &sparc64_ttable_tl0;
	unsigned int *insns;

	ttent += 0x820;
	ttent += (cpu_irq - 1) << 5;
	insns = (unsigned int *) ttent;
	insns[0] = SPARC_BRANCH(((unsigned long) handler),
				((unsigned long)&insns[0]));
	insns[1] = SPARC_NOP;
	__asm__ __volatile__("membar #StoreStore; flush %0" : : "r" (ttent));
}

int request_fast_irq(unsigned int irq,
		     irqreturn_t (*handler)(int, void *, struct pt_regs *),
		     unsigned long irqflags, const char *name, void *dev_id)
{
	struct irqaction *action;
	struct ino_bucket *bucket = __bucket(irq);
	unsigned long flags;

	/* No pil0 dummy buckets allowed here. */
	if (bucket < &ivector_table[0] ||
	    bucket >= &ivector_table[NUM_IVECS]) {
		unsigned int *caller;

		__asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
		printk(KERN_CRIT "request_fast_irq: Old style IRQ registry attempt "
		       "from %p, irq %08x.\n", caller, irq);
		return -EINVAL;
	}	
	
	if (!handler)
		return -EINVAL;

	if ((bucket->pil == 0) || (bucket->pil == 14)) {
		printk("request_fast_irq: Trying to register shared IRQ 0 or 14.\n");
		return -EBUSY;
	}

	spin_lock_irqsave(&irq_action_lock, flags);

	action = *(bucket->pil + irq_action);
	if (action) {
		if (action->flags & SA_SHIRQ)
			panic("Trying to register fast irq when already shared.\n");
		if (irqflags & SA_SHIRQ)
			panic("Trying to register fast irq as shared.\n");
		printk("request_fast_irq: Trying to register yet already owned.\n");
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return -EBUSY;
	}

	/*
	 * We do not check for SA_SAMPLE_RANDOM in this path. Neither do we
	 * support smp intr affinity in this path.
	 */
	if (irqflags & SA_STATIC_ALLOC) {
		if (static_irq_count < MAX_STATIC_ALLOC)
			action = &static_irqaction[static_irq_count++];
		else
			printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed "
			       "using kmalloc\n", bucket->pil, name);
	}
	if (action == NULL)
		action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
						     GFP_ATOMIC);
	if (!action) {
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return -ENOMEM;
	}
	install_fast_irq(bucket->pil, handler);

	bucket->irq_info = action;
	bucket->flags |= IBF_ACTIVE;

	action->handler = handler;
	action->flags = irqflags;
	action->dev_id = NULL;
	action->name = name;
	action->next = NULL;
	put_ino_in_irqaction(action, irq);
	put_smpaff_in_irqaction(action, CPU_MASK_NONE);

	*(bucket->pil + irq_action) = action;
	enable_irq(irq);

	spin_unlock_irqrestore(&irq_action_lock, flags);

#ifdef CONFIG_SMP
	distribute_irqs();
#endif
	return 0;
}

/* We really don't need these at all on the Sparc.  We only have
 * stubs here because they are exported to modules.
 */
unsigned long probe_irq_on(void)
{
	return 0;
}

EXPORT_SYMBOL(probe_irq_on);

int probe_irq_off(unsigned long mask)
{
	return 0;
}

EXPORT_SYMBOL(probe_irq_off);

#ifdef CONFIG_SMP
static int retarget_one_irq(struct irqaction *p, int goal_cpu)
{
	struct ino_bucket *bucket = get_ino_in_irqaction(p) + ivector_table;
	unsigned long imap = bucket->imap;
	unsigned int tid;

	while (!cpu_online(goal_cpu)) {
		if (++goal_cpu >= NR_CPUS)
			goal_cpu = 0;
	}

	if (tlb_type == cheetah || tlb_type == cheetah_plus) {
		tid = goal_cpu << 26;
		tid &= IMAP_AID_SAFARI;
	} else if (this_is_starfire == 0) {
		tid = goal_cpu << 26;
		tid &= IMAP_TID_UPA;
	} else {
		tid = (starfire_translate(imap, goal_cpu) << 26);
		tid &= IMAP_TID_UPA;
	}
	upa_writel(tid | IMAP_VALID, imap);

	do {
		if (++goal_cpu >= NR_CPUS)
			goal_cpu = 0;
	} while (!cpu_online(goal_cpu));

	return goal_cpu;
}

/* Called from request_irq. */
static void distribute_irqs(void)
{
	unsigned long flags;
	int cpu, level;

	spin_lock_irqsave(&irq_action_lock, flags);
	cpu = 0;

	/*
	 * Skip the timer at [0], and very rare error/power intrs at [15].
	 * Also level [12], it causes problems on Ex000 systems.
	 */
	for (level = 1; level < NR_IRQS; level++) {
		struct irqaction *p = irq_action[level];
		if (level == 12) continue;
		while(p) {
			cpu = retarget_one_irq(p, cpu);
			p = p->next;
		}
	}
	spin_unlock_irqrestore(&irq_action_lock, flags);
}
#endif


struct sun5_timer *prom_timers;
static u64 prom_limit0, prom_limit1;

static void map_prom_timers(void)
{
	unsigned int addr[3];
	int tnode, err;

	/* PROM timer node hangs out in the top level of device siblings... */
	tnode = prom_finddevice("/counter-timer");

	/* Assume if node is not present, PROM uses different tick mechanism
	 * which we should not care about.
	 */
	if (tnode == 0 || tnode == -1) {
		prom_timers = (struct sun5_timer *) 0;
		return;
	}

	/* If PROM is really using this, it must be mapped by him. */
	err = prom_getproperty(tnode, "address", (char *)addr, sizeof(addr));
	if (err == -1) {
		prom_printf("PROM does not have timer mapped, trying to continue.\n");
		prom_timers = (struct sun5_timer *) 0;
		return;
	}
	prom_timers = (struct sun5_timer *) ((unsigned long)addr[0]);
}

static void kill_prom_timer(void)
{
	if (!prom_timers)
		return;

	/* Save them away for later. */
	prom_limit0 = prom_timers->limit0;
	prom_limit1 = prom_timers->limit1;

	/* Just as in sun4c/sun4m PROM uses timer which ticks at IRQ 14.
	 * We turn both off here just to be paranoid.
	 */
	prom_timers->limit0 = 0;
	prom_timers->limit1 = 0;

	/* Wheee, eat the interrupt packet too... */
	__asm__ __volatile__(
"	mov	0x40, %%g2\n"
"	ldxa	[%%g0] %0, %%g1\n"
"	ldxa	[%%g2] %1, %%g1\n"
"	stxa	%%g0, [%%g0] %0\n"
"	membar	#Sync\n"
	: /* no outputs */
	: "i" (ASI_INTR_RECEIVE), "i" (ASI_INTR_R)
	: "g1", "g2");
}

void enable_prom_timer(void)
{
	if (!prom_timers)
		return;

	/* Set it to whatever was there before. */
	prom_timers->limit1 = prom_limit1;
	prom_timers->count1 = 0;
	prom_timers->limit0 = prom_limit0;
	prom_timers->count0 = 0;
}

void init_irqwork_curcpu(void)
{
	register struct irq_work_struct *workp asm("o2");
	register unsigned long tmp asm("o3");
	int cpu = hard_smp_processor_id();

	memset(__irq_work + cpu, 0, sizeof(*workp));

	/* Make sure we are called with PSTATE_IE disabled.  */
	__asm__ __volatile__("rdpr	%%pstate, %0\n\t"
			     : "=r" (tmp));
	if (tmp & PSTATE_IE) {
		prom_printf("BUG: init_irqwork_curcpu() called with "
			    "PSTATE_IE enabled, bailing.\n");
		__asm__ __volatile__("mov	%%i7, %0\n\t"
				     : "=r" (tmp));
		prom_printf("BUG: Called from %lx\n", tmp);
		prom_halt();
	}

	/* Set interrupt globals.  */
	workp = &__irq_work[cpu];
	__asm__ __volatile__(
	"rdpr	%%pstate, %0\n\t"
	"wrpr	%0, %1, %%pstate\n\t"
	"mov	%2, %%g6\n\t"
	"wrpr	%0, 0x0, %%pstate\n\t"
	: "=&r" (tmp)
	: "i" (PSTATE_IG), "r" (workp));
}

/* Only invoked on boot processor. */
void __init init_IRQ(void)
{
	map_prom_timers();
	kill_prom_timer();
	memset(&ivector_table[0], 0, sizeof(ivector_table));

	/* We need to clear any IRQ's pending in the soft interrupt
	 * registers, a spurious one could be left around from the
	 * PROM timer which we just disabled.
	 */
	clear_softint(get_softint());

	/* Now that ivector table is initialized, it is safe
	 * to receive IRQ vector traps.  We will normally take
	 * one or two right now, in case some device PROM used
	 * to boot us wants to speak to us.  We just ignore them.
	 */
	__asm__ __volatile__("rdpr	%%pstate, %%g1\n\t"
			     "or	%%g1, %0, %%g1\n\t"
			     "wrpr	%%g1, 0x0, %%pstate"
			     : /* No outputs */
			     : "i" (PSTATE_IE)
			     : "g1");
}

static struct proc_dir_entry * root_irq_dir;
static struct proc_dir_entry * irq_dir [NUM_IVECS];

#ifdef CONFIG_SMP

static int irq_affinity_read_proc (char *page, char **start, off_t off,
			int count, int *eof, void *data)
{
	struct ino_bucket *bp = ivector_table + (long)data;
	struct irqaction *ap = bp->irq_info;
	cpumask_t mask;
	int len;

	mask = get_smpaff_in_irqaction(ap);
	if (cpus_empty(mask))
		mask = cpu_online_map;

	len = cpumask_scnprintf(page, count, mask);
	if (count - len < 2)
		return -EINVAL;
	len += sprintf(page + len, "\n");
	return len;
}

static inline void set_intr_affinity(int irq, cpumask_t hw_aff)
{
	struct ino_bucket *bp = ivector_table + irq;

	/* Users specify affinity in terms of hw cpu ids.
	 * As soon as we do this, handler_irq() might see and take action.
	 */
	put_smpaff_in_irqaction((struct irqaction *)bp->irq_info, hw_aff);

	/* Migration is simply done by the next cpu to service this
	 * interrupt.
	 */
}

static int irq_affinity_write_proc (struct file *file, const char __user *buffer,
					unsigned long count, void *data)
{
	int irq = (long) data, full_count = count, err;
	cpumask_t new_value;

	err = cpumask_parse(buffer, count, new_value);

	/*
	 * Do not allow disabling IRQs completely - it's a too easy
	 * way to make the system unusable accidentally :-) At least
	 * one online CPU still has to be targeted.
	 */
	cpus_and(new_value, new_value, cpu_online_map);
	if (cpus_empty(new_value))
		return -EINVAL;

	set_intr_affinity(irq, new_value);

	return full_count;
}

#endif

#define MAX_NAMELEN 10

static void register_irq_proc (unsigned int irq)
{
	char name [MAX_NAMELEN];

	if (!root_irq_dir || irq_dir[irq])
		return;

	memset(name, 0, MAX_NAMELEN);
	sprintf(name, "%x", irq);

	/* create /proc/irq/1234 */
	irq_dir[irq] = proc_mkdir(name, root_irq_dir);

#ifdef CONFIG_SMP
	/* XXX SMP affinity not supported on starfire yet. */
	if (this_is_starfire == 0) {
		struct proc_dir_entry *entry;

		/* create /proc/irq/1234/smp_affinity */
		entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]);

		if (entry) {
			entry->nlink = 1;
			entry->data = (void *)(long)irq;
			entry->read_proc = irq_affinity_read_proc;
			entry->write_proc = irq_affinity_write_proc;
		}
	}
#endif
}

void init_irq_proc (void)
{
	/* create /proc/irq */
	root_irq_dir = proc_mkdir("irq", NULL);
}