xref: /linux/arch/x86/kernel/apic/vector.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Local APIC related interfaces to support IOAPIC, MSI, HT_IRQ etc.
3  *
4  * Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
5  *	Moved from arch/x86/kernel/apic/io_apic.c.
6  * Jiang Liu <jiang.liu@linux.intel.com>
7  *	Enable support of hierarchical irqdomains
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/interrupt.h>
14 #include <linux/init.h>
15 #include <linux/compiler.h>
16 #include <linux/slab.h>
17 #include <asm/irqdomain.h>
18 #include <asm/hw_irq.h>
19 #include <asm/apic.h>
20 #include <asm/i8259.h>
21 #include <asm/desc.h>
22 #include <asm/irq_remapping.h>
23 
24 struct apic_chip_data {
25 	struct irq_cfg		cfg;
26 	cpumask_var_t		domain;
27 	cpumask_var_t		old_domain;
28 	u8			move_in_progress : 1;
29 };
30 
31 struct irq_domain *x86_vector_domain;
32 static DEFINE_RAW_SPINLOCK(vector_lock);
33 static cpumask_var_t vector_cpumask;
34 static struct irq_chip lapic_controller;
35 #ifdef	CONFIG_X86_IO_APIC
36 static struct apic_chip_data *legacy_irq_data[NR_IRQS_LEGACY];
37 #endif
38 
39 void lock_vector_lock(void)
40 {
41 	/* Used to the online set of cpus does not change
42 	 * during assign_irq_vector.
43 	 */
44 	raw_spin_lock(&vector_lock);
45 }
46 
47 void unlock_vector_lock(void)
48 {
49 	raw_spin_unlock(&vector_lock);
50 }
51 
52 static struct apic_chip_data *apic_chip_data(struct irq_data *irq_data)
53 {
54 	if (!irq_data)
55 		return NULL;
56 
57 	while (irq_data->parent_data)
58 		irq_data = irq_data->parent_data;
59 
60 	return irq_data->chip_data;
61 }
62 
63 struct irq_cfg *irqd_cfg(struct irq_data *irq_data)
64 {
65 	struct apic_chip_data *data = apic_chip_data(irq_data);
66 
67 	return data ? &data->cfg : NULL;
68 }
69 
70 struct irq_cfg *irq_cfg(unsigned int irq)
71 {
72 	return irqd_cfg(irq_get_irq_data(irq));
73 }
74 
75 static struct apic_chip_data *alloc_apic_chip_data(int node)
76 {
77 	struct apic_chip_data *data;
78 
79 	data = kzalloc_node(sizeof(*data), GFP_KERNEL, node);
80 	if (!data)
81 		return NULL;
82 	if (!zalloc_cpumask_var_node(&data->domain, GFP_KERNEL, node))
83 		goto out_data;
84 	if (!zalloc_cpumask_var_node(&data->old_domain, GFP_KERNEL, node))
85 		goto out_domain;
86 	return data;
87 out_domain:
88 	free_cpumask_var(data->domain);
89 out_data:
90 	kfree(data);
91 	return NULL;
92 }
93 
94 static void free_apic_chip_data(struct apic_chip_data *data)
95 {
96 	if (data) {
97 		free_cpumask_var(data->domain);
98 		free_cpumask_var(data->old_domain);
99 		kfree(data);
100 	}
101 }
102 
103 static int __assign_irq_vector(int irq, struct apic_chip_data *d,
104 			       const struct cpumask *mask)
105 {
106 	/*
107 	 * NOTE! The local APIC isn't very good at handling
108 	 * multiple interrupts at the same interrupt level.
109 	 * As the interrupt level is determined by taking the
110 	 * vector number and shifting that right by 4, we
111 	 * want to spread these out a bit so that they don't
112 	 * all fall in the same interrupt level.
113 	 *
114 	 * Also, we've got to be careful not to trash gate
115 	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
116 	 */
117 	static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
118 	static int current_offset = VECTOR_OFFSET_START % 16;
119 	int cpu, err;
120 
121 	if (d->move_in_progress)
122 		return -EBUSY;
123 
124 	/* Only try and allocate irqs on cpus that are present */
125 	err = -ENOSPC;
126 	cpumask_clear(d->old_domain);
127 	cpu = cpumask_first_and(mask, cpu_online_mask);
128 	while (cpu < nr_cpu_ids) {
129 		int new_cpu, vector, offset;
130 
131 		apic->vector_allocation_domain(cpu, vector_cpumask, mask);
132 
133 		if (cpumask_subset(vector_cpumask, d->domain)) {
134 			err = 0;
135 			if (cpumask_equal(vector_cpumask, d->domain))
136 				break;
137 			/*
138 			 * New cpumask using the vector is a proper subset of
139 			 * the current in use mask. So cleanup the vector
140 			 * allocation for the members that are not used anymore.
141 			 */
142 			cpumask_andnot(d->old_domain, d->domain,
143 				       vector_cpumask);
144 			d->move_in_progress =
145 			   cpumask_intersects(d->old_domain, cpu_online_mask);
146 			cpumask_and(d->domain, d->domain, vector_cpumask);
147 			break;
148 		}
149 
150 		vector = current_vector;
151 		offset = current_offset;
152 next:
153 		vector += 16;
154 		if (vector >= first_system_vector) {
155 			offset = (offset + 1) % 16;
156 			vector = FIRST_EXTERNAL_VECTOR + offset;
157 		}
158 
159 		if (unlikely(current_vector == vector)) {
160 			cpumask_or(d->old_domain, d->old_domain,
161 				   vector_cpumask);
162 			cpumask_andnot(vector_cpumask, mask, d->old_domain);
163 			cpu = cpumask_first_and(vector_cpumask,
164 						cpu_online_mask);
165 			continue;
166 		}
167 
168 		if (test_bit(vector, used_vectors))
169 			goto next;
170 
171 		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask) {
172 			if (!IS_ERR_OR_NULL(per_cpu(vector_irq, new_cpu)[vector]))
173 				goto next;
174 		}
175 		/* Found one! */
176 		current_vector = vector;
177 		current_offset = offset;
178 		if (d->cfg.vector) {
179 			cpumask_copy(d->old_domain, d->domain);
180 			d->move_in_progress =
181 			   cpumask_intersects(d->old_domain, cpu_online_mask);
182 		}
183 		for_each_cpu_and(new_cpu, vector_cpumask, cpu_online_mask)
184 			per_cpu(vector_irq, new_cpu)[vector] = irq_to_desc(irq);
185 		d->cfg.vector = vector;
186 		cpumask_copy(d->domain, vector_cpumask);
187 		err = 0;
188 		break;
189 	}
190 
191 	if (!err) {
192 		/* cache destination APIC IDs into cfg->dest_apicid */
193 		err = apic->cpu_mask_to_apicid_and(mask, d->domain,
194 						   &d->cfg.dest_apicid);
195 	}
196 
197 	return err;
198 }
199 
200 static int assign_irq_vector(int irq, struct apic_chip_data *data,
201 			     const struct cpumask *mask)
202 {
203 	int err;
204 	unsigned long flags;
205 
206 	raw_spin_lock_irqsave(&vector_lock, flags);
207 	err = __assign_irq_vector(irq, data, mask);
208 	raw_spin_unlock_irqrestore(&vector_lock, flags);
209 	return err;
210 }
211 
212 static int assign_irq_vector_policy(int irq, int node,
213 				    struct apic_chip_data *data,
214 				    struct irq_alloc_info *info)
215 {
216 	if (info && info->mask)
217 		return assign_irq_vector(irq, data, info->mask);
218 	if (node != NUMA_NO_NODE &&
219 	    assign_irq_vector(irq, data, cpumask_of_node(node)) == 0)
220 		return 0;
221 	return assign_irq_vector(irq, data, apic->target_cpus());
222 }
223 
224 static void clear_irq_vector(int irq, struct apic_chip_data *data)
225 {
226 	struct irq_desc *desc;
227 	unsigned long flags;
228 	int cpu, vector;
229 
230 	raw_spin_lock_irqsave(&vector_lock, flags);
231 	BUG_ON(!data->cfg.vector);
232 
233 	vector = data->cfg.vector;
234 	for_each_cpu_and(cpu, data->domain, cpu_online_mask)
235 		per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
236 
237 	data->cfg.vector = 0;
238 	cpumask_clear(data->domain);
239 
240 	if (likely(!data->move_in_progress)) {
241 		raw_spin_unlock_irqrestore(&vector_lock, flags);
242 		return;
243 	}
244 
245 	desc = irq_to_desc(irq);
246 	for_each_cpu_and(cpu, data->old_domain, cpu_online_mask) {
247 		for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
248 		     vector++) {
249 			if (per_cpu(vector_irq, cpu)[vector] != desc)
250 				continue;
251 			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
252 			break;
253 		}
254 	}
255 	data->move_in_progress = 0;
256 	raw_spin_unlock_irqrestore(&vector_lock, flags);
257 }
258 
259 void init_irq_alloc_info(struct irq_alloc_info *info,
260 			 const struct cpumask *mask)
261 {
262 	memset(info, 0, sizeof(*info));
263 	info->mask = mask;
264 }
265 
266 void copy_irq_alloc_info(struct irq_alloc_info *dst, struct irq_alloc_info *src)
267 {
268 	if (src)
269 		*dst = *src;
270 	else
271 		memset(dst, 0, sizeof(*dst));
272 }
273 
274 static void x86_vector_free_irqs(struct irq_domain *domain,
275 				 unsigned int virq, unsigned int nr_irqs)
276 {
277 	struct irq_data *irq_data;
278 	int i;
279 
280 	for (i = 0; i < nr_irqs; i++) {
281 		irq_data = irq_domain_get_irq_data(x86_vector_domain, virq + i);
282 		if (irq_data && irq_data->chip_data) {
283 			clear_irq_vector(virq + i, irq_data->chip_data);
284 			free_apic_chip_data(irq_data->chip_data);
285 #ifdef	CONFIG_X86_IO_APIC
286 			if (virq + i < nr_legacy_irqs())
287 				legacy_irq_data[virq + i] = NULL;
288 #endif
289 			irq_domain_reset_irq_data(irq_data);
290 		}
291 	}
292 }
293 
294 static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq,
295 				 unsigned int nr_irqs, void *arg)
296 {
297 	struct irq_alloc_info *info = arg;
298 	struct apic_chip_data *data;
299 	struct irq_data *irq_data;
300 	int i, err, node;
301 
302 	if (disable_apic)
303 		return -ENXIO;
304 
305 	/* Currently vector allocator can't guarantee contiguous allocations */
306 	if ((info->flags & X86_IRQ_ALLOC_CONTIGUOUS_VECTORS) && nr_irqs > 1)
307 		return -ENOSYS;
308 
309 	for (i = 0; i < nr_irqs; i++) {
310 		irq_data = irq_domain_get_irq_data(domain, virq + i);
311 		BUG_ON(!irq_data);
312 		node = irq_data_get_node(irq_data);
313 #ifdef	CONFIG_X86_IO_APIC
314 		if (virq + i < nr_legacy_irqs() && legacy_irq_data[virq + i])
315 			data = legacy_irq_data[virq + i];
316 		else
317 #endif
318 			data = alloc_apic_chip_data(node);
319 		if (!data) {
320 			err = -ENOMEM;
321 			goto error;
322 		}
323 
324 		irq_data->chip = &lapic_controller;
325 		irq_data->chip_data = data;
326 		irq_data->hwirq = virq + i;
327 		err = assign_irq_vector_policy(virq + i, node, data, info);
328 		if (err)
329 			goto error;
330 	}
331 
332 	return 0;
333 
334 error:
335 	x86_vector_free_irqs(domain, virq, i + 1);
336 	return err;
337 }
338 
339 static const struct irq_domain_ops x86_vector_domain_ops = {
340 	.alloc	= x86_vector_alloc_irqs,
341 	.free	= x86_vector_free_irqs,
342 };
343 
344 int __init arch_probe_nr_irqs(void)
345 {
346 	int nr;
347 
348 	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
349 		nr_irqs = NR_VECTORS * nr_cpu_ids;
350 
351 	nr = (gsi_top + nr_legacy_irqs()) + 8 * nr_cpu_ids;
352 #if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
353 	/*
354 	 * for MSI and HT dyn irq
355 	 */
356 	if (gsi_top <= NR_IRQS_LEGACY)
357 		nr +=  8 * nr_cpu_ids;
358 	else
359 		nr += gsi_top * 16;
360 #endif
361 	if (nr < nr_irqs)
362 		nr_irqs = nr;
363 
364 	return nr_legacy_irqs();
365 }
366 
367 #ifdef	CONFIG_X86_IO_APIC
368 static void init_legacy_irqs(void)
369 {
370 	int i, node = cpu_to_node(0);
371 	struct apic_chip_data *data;
372 
373 	/*
374 	 * For legacy IRQ's, start with assigning irq0 to irq15 to
375 	 * ISA_IRQ_VECTOR(i) for all cpu's.
376 	 */
377 	for (i = 0; i < nr_legacy_irqs(); i++) {
378 		data = legacy_irq_data[i] = alloc_apic_chip_data(node);
379 		BUG_ON(!data);
380 
381 		data->cfg.vector = ISA_IRQ_VECTOR(i);
382 		cpumask_setall(data->domain);
383 		irq_set_chip_data(i, data);
384 	}
385 }
386 #else
387 static void init_legacy_irqs(void) { }
388 #endif
389 
390 int __init arch_early_irq_init(void)
391 {
392 	init_legacy_irqs();
393 
394 	x86_vector_domain = irq_domain_add_tree(NULL, &x86_vector_domain_ops,
395 						NULL);
396 	BUG_ON(x86_vector_domain == NULL);
397 	irq_set_default_host(x86_vector_domain);
398 
399 	arch_init_msi_domain(x86_vector_domain);
400 	arch_init_htirq_domain(x86_vector_domain);
401 
402 	BUG_ON(!alloc_cpumask_var(&vector_cpumask, GFP_KERNEL));
403 
404 	return arch_early_ioapic_init();
405 }
406 
407 /* Initialize vector_irq on a new cpu */
408 static void __setup_vector_irq(int cpu)
409 {
410 	struct apic_chip_data *data;
411 	struct irq_desc *desc;
412 	int irq, vector;
413 
414 	/* Mark the inuse vectors */
415 	for_each_irq_desc(irq, desc) {
416 		struct irq_data *idata = irq_desc_get_irq_data(desc);
417 
418 		data = apic_chip_data(idata);
419 		if (!data || !cpumask_test_cpu(cpu, data->domain))
420 			continue;
421 		vector = data->cfg.vector;
422 		per_cpu(vector_irq, cpu)[vector] = desc;
423 	}
424 	/* Mark the free vectors */
425 	for (vector = 0; vector < NR_VECTORS; ++vector) {
426 		desc = per_cpu(vector_irq, cpu)[vector];
427 		if (IS_ERR_OR_NULL(desc))
428 			continue;
429 
430 		data = apic_chip_data(irq_desc_get_irq_data(desc));
431 		if (!cpumask_test_cpu(cpu, data->domain))
432 			per_cpu(vector_irq, cpu)[vector] = VECTOR_UNUSED;
433 	}
434 }
435 
436 /*
437  * Setup the vector to irq mappings. Must be called with vector_lock held.
438  */
439 void setup_vector_irq(int cpu)
440 {
441 	int irq;
442 
443 	lockdep_assert_held(&vector_lock);
444 	/*
445 	 * On most of the platforms, legacy PIC delivers the interrupts on the
446 	 * boot cpu. But there are certain platforms where PIC interrupts are
447 	 * delivered to multiple cpu's. If the legacy IRQ is handled by the
448 	 * legacy PIC, for the new cpu that is coming online, setup the static
449 	 * legacy vector to irq mapping:
450 	 */
451 	for (irq = 0; irq < nr_legacy_irqs(); irq++)
452 		per_cpu(vector_irq, cpu)[ISA_IRQ_VECTOR(irq)] = irq_to_desc(irq);
453 
454 	__setup_vector_irq(cpu);
455 }
456 
457 static int apic_retrigger_irq(struct irq_data *irq_data)
458 {
459 	struct apic_chip_data *data = apic_chip_data(irq_data);
460 	unsigned long flags;
461 	int cpu;
462 
463 	raw_spin_lock_irqsave(&vector_lock, flags);
464 	cpu = cpumask_first_and(data->domain, cpu_online_mask);
465 	apic->send_IPI_mask(cpumask_of(cpu), data->cfg.vector);
466 	raw_spin_unlock_irqrestore(&vector_lock, flags);
467 
468 	return 1;
469 }
470 
471 void apic_ack_edge(struct irq_data *data)
472 {
473 	irq_complete_move(irqd_cfg(data));
474 	irq_move_irq(data);
475 	ack_APIC_irq();
476 }
477 
478 static int apic_set_affinity(struct irq_data *irq_data,
479 			     const struct cpumask *dest, bool force)
480 {
481 	struct apic_chip_data *data = irq_data->chip_data;
482 	int err, irq = irq_data->irq;
483 
484 	if (!config_enabled(CONFIG_SMP))
485 		return -EPERM;
486 
487 	if (!cpumask_intersects(dest, cpu_online_mask))
488 		return -EINVAL;
489 
490 	err = assign_irq_vector(irq, data, dest);
491 	if (err) {
492 		if (assign_irq_vector(irq, data,
493 				      irq_data_get_affinity_mask(irq_data)))
494 			pr_err("Failed to recover vector for irq %d\n", irq);
495 		return err;
496 	}
497 
498 	return IRQ_SET_MASK_OK;
499 }
500 
501 static struct irq_chip lapic_controller = {
502 	.irq_ack		= apic_ack_edge,
503 	.irq_set_affinity	= apic_set_affinity,
504 	.irq_retrigger		= apic_retrigger_irq,
505 };
506 
507 #ifdef CONFIG_SMP
508 static void __send_cleanup_vector(struct apic_chip_data *data)
509 {
510 	cpumask_var_t cleanup_mask;
511 
512 	if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
513 		unsigned int i;
514 
515 		for_each_cpu_and(i, data->old_domain, cpu_online_mask)
516 			apic->send_IPI_mask(cpumask_of(i),
517 					    IRQ_MOVE_CLEANUP_VECTOR);
518 	} else {
519 		cpumask_and(cleanup_mask, data->old_domain, cpu_online_mask);
520 		apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
521 		free_cpumask_var(cleanup_mask);
522 	}
523 	data->move_in_progress = 0;
524 }
525 
526 void send_cleanup_vector(struct irq_cfg *cfg)
527 {
528 	struct apic_chip_data *data;
529 
530 	data = container_of(cfg, struct apic_chip_data, cfg);
531 	if (data->move_in_progress)
532 		__send_cleanup_vector(data);
533 }
534 
535 asmlinkage __visible void smp_irq_move_cleanup_interrupt(void)
536 {
537 	unsigned vector, me;
538 
539 	entering_ack_irq();
540 
541 	/* Prevent vectors vanishing under us */
542 	raw_spin_lock(&vector_lock);
543 
544 	me = smp_processor_id();
545 	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
546 		struct apic_chip_data *data;
547 		struct irq_desc *desc;
548 		unsigned int irr;
549 
550 	retry:
551 		desc = __this_cpu_read(vector_irq[vector]);
552 		if (IS_ERR_OR_NULL(desc))
553 			continue;
554 
555 		if (!raw_spin_trylock(&desc->lock)) {
556 			raw_spin_unlock(&vector_lock);
557 			cpu_relax();
558 			raw_spin_lock(&vector_lock);
559 			goto retry;
560 		}
561 
562 		data = apic_chip_data(irq_desc_get_irq_data(desc));
563 		if (!data)
564 			goto unlock;
565 
566 		/*
567 		 * Check if the irq migration is in progress. If so, we
568 		 * haven't received the cleanup request yet for this irq.
569 		 */
570 		if (data->move_in_progress)
571 			goto unlock;
572 
573 		if (vector == data->cfg.vector &&
574 		    cpumask_test_cpu(me, data->domain))
575 			goto unlock;
576 
577 		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
578 		/*
579 		 * Check if the vector that needs to be cleanedup is
580 		 * registered at the cpu's IRR. If so, then this is not
581 		 * the best time to clean it up. Lets clean it up in the
582 		 * next attempt by sending another IRQ_MOVE_CLEANUP_VECTOR
583 		 * to myself.
584 		 */
585 		if (irr  & (1 << (vector % 32))) {
586 			apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
587 			goto unlock;
588 		}
589 		__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
590 unlock:
591 		raw_spin_unlock(&desc->lock);
592 	}
593 
594 	raw_spin_unlock(&vector_lock);
595 
596 	exiting_irq();
597 }
598 
599 static void __irq_complete_move(struct irq_cfg *cfg, unsigned vector)
600 {
601 	unsigned me;
602 	struct apic_chip_data *data;
603 
604 	data = container_of(cfg, struct apic_chip_data, cfg);
605 	if (likely(!data->move_in_progress))
606 		return;
607 
608 	me = smp_processor_id();
609 	if (vector == data->cfg.vector && cpumask_test_cpu(me, data->domain))
610 		__send_cleanup_vector(data);
611 }
612 
613 void irq_complete_move(struct irq_cfg *cfg)
614 {
615 	__irq_complete_move(cfg, ~get_irq_regs()->orig_ax);
616 }
617 
618 void irq_force_complete_move(int irq)
619 {
620 	struct irq_cfg *cfg = irq_cfg(irq);
621 
622 	if (cfg)
623 		__irq_complete_move(cfg, cfg->vector);
624 }
625 #endif
626 
627 static void __init print_APIC_field(int base)
628 {
629 	int i;
630 
631 	printk(KERN_DEBUG);
632 
633 	for (i = 0; i < 8; i++)
634 		pr_cont("%08x", apic_read(base + i*0x10));
635 
636 	pr_cont("\n");
637 }
638 
639 static void __init print_local_APIC(void *dummy)
640 {
641 	unsigned int i, v, ver, maxlvt;
642 	u64 icr;
643 
644 	pr_debug("printing local APIC contents on CPU#%d/%d:\n",
645 		 smp_processor_id(), hard_smp_processor_id());
646 	v = apic_read(APIC_ID);
647 	pr_info("... APIC ID:      %08x (%01x)\n", v, read_apic_id());
648 	v = apic_read(APIC_LVR);
649 	pr_info("... APIC VERSION: %08x\n", v);
650 	ver = GET_APIC_VERSION(v);
651 	maxlvt = lapic_get_maxlvt();
652 
653 	v = apic_read(APIC_TASKPRI);
654 	pr_debug("... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
655 
656 	/* !82489DX */
657 	if (APIC_INTEGRATED(ver)) {
658 		if (!APIC_XAPIC(ver)) {
659 			v = apic_read(APIC_ARBPRI);
660 			pr_debug("... APIC ARBPRI: %08x (%02x)\n",
661 				 v, v & APIC_ARBPRI_MASK);
662 		}
663 		v = apic_read(APIC_PROCPRI);
664 		pr_debug("... APIC PROCPRI: %08x\n", v);
665 	}
666 
667 	/*
668 	 * Remote read supported only in the 82489DX and local APIC for
669 	 * Pentium processors.
670 	 */
671 	if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
672 		v = apic_read(APIC_RRR);
673 		pr_debug("... APIC RRR: %08x\n", v);
674 	}
675 
676 	v = apic_read(APIC_LDR);
677 	pr_debug("... APIC LDR: %08x\n", v);
678 	if (!x2apic_enabled()) {
679 		v = apic_read(APIC_DFR);
680 		pr_debug("... APIC DFR: %08x\n", v);
681 	}
682 	v = apic_read(APIC_SPIV);
683 	pr_debug("... APIC SPIV: %08x\n", v);
684 
685 	pr_debug("... APIC ISR field:\n");
686 	print_APIC_field(APIC_ISR);
687 	pr_debug("... APIC TMR field:\n");
688 	print_APIC_field(APIC_TMR);
689 	pr_debug("... APIC IRR field:\n");
690 	print_APIC_field(APIC_IRR);
691 
692 	/* !82489DX */
693 	if (APIC_INTEGRATED(ver)) {
694 		/* Due to the Pentium erratum 3AP. */
695 		if (maxlvt > 3)
696 			apic_write(APIC_ESR, 0);
697 
698 		v = apic_read(APIC_ESR);
699 		pr_debug("... APIC ESR: %08x\n", v);
700 	}
701 
702 	icr = apic_icr_read();
703 	pr_debug("... APIC ICR: %08x\n", (u32)icr);
704 	pr_debug("... APIC ICR2: %08x\n", (u32)(icr >> 32));
705 
706 	v = apic_read(APIC_LVTT);
707 	pr_debug("... APIC LVTT: %08x\n", v);
708 
709 	if (maxlvt > 3) {
710 		/* PC is LVT#4. */
711 		v = apic_read(APIC_LVTPC);
712 		pr_debug("... APIC LVTPC: %08x\n", v);
713 	}
714 	v = apic_read(APIC_LVT0);
715 	pr_debug("... APIC LVT0: %08x\n", v);
716 	v = apic_read(APIC_LVT1);
717 	pr_debug("... APIC LVT1: %08x\n", v);
718 
719 	if (maxlvt > 2) {
720 		/* ERR is LVT#3. */
721 		v = apic_read(APIC_LVTERR);
722 		pr_debug("... APIC LVTERR: %08x\n", v);
723 	}
724 
725 	v = apic_read(APIC_TMICT);
726 	pr_debug("... APIC TMICT: %08x\n", v);
727 	v = apic_read(APIC_TMCCT);
728 	pr_debug("... APIC TMCCT: %08x\n", v);
729 	v = apic_read(APIC_TDCR);
730 	pr_debug("... APIC TDCR: %08x\n", v);
731 
732 	if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
733 		v = apic_read(APIC_EFEAT);
734 		maxlvt = (v >> 16) & 0xff;
735 		pr_debug("... APIC EFEAT: %08x\n", v);
736 		v = apic_read(APIC_ECTRL);
737 		pr_debug("... APIC ECTRL: %08x\n", v);
738 		for (i = 0; i < maxlvt; i++) {
739 			v = apic_read(APIC_EILVTn(i));
740 			pr_debug("... APIC EILVT%d: %08x\n", i, v);
741 		}
742 	}
743 	pr_cont("\n");
744 }
745 
746 static void __init print_local_APICs(int maxcpu)
747 {
748 	int cpu;
749 
750 	if (!maxcpu)
751 		return;
752 
753 	preempt_disable();
754 	for_each_online_cpu(cpu) {
755 		if (cpu >= maxcpu)
756 			break;
757 		smp_call_function_single(cpu, print_local_APIC, NULL, 1);
758 	}
759 	preempt_enable();
760 }
761 
762 static void __init print_PIC(void)
763 {
764 	unsigned int v;
765 	unsigned long flags;
766 
767 	if (!nr_legacy_irqs())
768 		return;
769 
770 	pr_debug("\nprinting PIC contents\n");
771 
772 	raw_spin_lock_irqsave(&i8259A_lock, flags);
773 
774 	v = inb(0xa1) << 8 | inb(0x21);
775 	pr_debug("... PIC  IMR: %04x\n", v);
776 
777 	v = inb(0xa0) << 8 | inb(0x20);
778 	pr_debug("... PIC  IRR: %04x\n", v);
779 
780 	outb(0x0b, 0xa0);
781 	outb(0x0b, 0x20);
782 	v = inb(0xa0) << 8 | inb(0x20);
783 	outb(0x0a, 0xa0);
784 	outb(0x0a, 0x20);
785 
786 	raw_spin_unlock_irqrestore(&i8259A_lock, flags);
787 
788 	pr_debug("... PIC  ISR: %04x\n", v);
789 
790 	v = inb(0x4d1) << 8 | inb(0x4d0);
791 	pr_debug("... PIC ELCR: %04x\n", v);
792 }
793 
794 static int show_lapic __initdata = 1;
795 static __init int setup_show_lapic(char *arg)
796 {
797 	int num = -1;
798 
799 	if (strcmp(arg, "all") == 0) {
800 		show_lapic = CONFIG_NR_CPUS;
801 	} else {
802 		get_option(&arg, &num);
803 		if (num >= 0)
804 			show_lapic = num;
805 	}
806 
807 	return 1;
808 }
809 __setup("show_lapic=", setup_show_lapic);
810 
811 static int __init print_ICs(void)
812 {
813 	if (apic_verbosity == APIC_QUIET)
814 		return 0;
815 
816 	print_PIC();
817 
818 	/* don't print out if apic is not there */
819 	if (!cpu_has_apic && !apic_from_smp_config())
820 		return 0;
821 
822 	print_local_APICs(show_lapic);
823 	print_IO_APICs();
824 
825 	return 0;
826 }
827 
828 late_initcall(print_ICs);
829