xref: /openbmc/linux/arch/x86/kernel/apic/io_apic.c (revision ded1f6ab)
1 /*
2  *	Intel IO-APIC support for multi-Pentium hosts.
3  *
4  *	Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
5  *
6  *	Many thanks to Stig Venaas for trying out countless experimental
7  *	patches and reporting/debugging problems patiently!
8  *
9  *	(c) 1999, Multiple IO-APIC support, developed by
10  *	Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
11  *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
12  *	further tested and cleaned up by Zach Brown <zab@redhat.com>
13  *	and Ingo Molnar <mingo@redhat.com>
14  *
15  *	Fixes
16  *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
17  *					thanks to Eric Gilmore
18  *					and Rolf G. Tews
19  *					for testing these extensively
20  *	Paul Diefenbaugh	:	Added full ACPI support
21  */
22 
23 #include <linux/mm.h>
24 #include <linux/interrupt.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/sched.h>
28 #include <linux/pci.h>
29 #include <linux/mc146818rtc.h>
30 #include <linux/compiler.h>
31 #include <linux/acpi.h>
32 #include <linux/module.h>
33 #include <linux/syscore_ops.h>
34 #include <linux/msi.h>
35 #include <linux/htirq.h>
36 #include <linux/freezer.h>
37 #include <linux/kthread.h>
38 #include <linux/jiffies.h>	/* time_after() */
39 #include <linux/slab.h>
40 #ifdef CONFIG_ACPI
41 #include <acpi/acpi_bus.h>
42 #endif
43 #include <linux/bootmem.h>
44 #include <linux/dmar.h>
45 #include <linux/hpet.h>
46 
47 #include <asm/idle.h>
48 #include <asm/io.h>
49 #include <asm/smp.h>
50 #include <asm/cpu.h>
51 #include <asm/desc.h>
52 #include <asm/proto.h>
53 #include <asm/acpi.h>
54 #include <asm/dma.h>
55 #include <asm/timer.h>
56 #include <asm/i8259.h>
57 #include <asm/msidef.h>
58 #include <asm/hypertransport.h>
59 #include <asm/setup.h>
60 #include <asm/irq_remapping.h>
61 #include <asm/hpet.h>
62 #include <asm/hw_irq.h>
63 
64 #include <asm/apic.h>
65 
66 #define __apicdebuginit(type) static type __init
67 #define for_each_irq_pin(entry, head) \
68 	for (entry = head; entry; entry = entry->next)
69 
70 /*
71  *      Is the SiS APIC rmw bug present ?
72  *      -1 = don't know, 0 = no, 1 = yes
73  */
74 int sis_apic_bug = -1;
75 
76 static DEFINE_RAW_SPINLOCK(ioapic_lock);
77 static DEFINE_RAW_SPINLOCK(vector_lock);
78 
79 static struct ioapic {
80 	/*
81 	 * # of IRQ routing registers
82 	 */
83 	int nr_registers;
84 	/*
85 	 * Saved state during suspend/resume, or while enabling intr-remap.
86 	 */
87 	struct IO_APIC_route_entry *saved_registers;
88 	/* I/O APIC config */
89 	struct mpc_ioapic mp_config;
90 	/* IO APIC gsi routing info */
91 	struct mp_ioapic_gsi  gsi_config;
92 	DECLARE_BITMAP(pin_programmed, MP_MAX_IOAPIC_PIN + 1);
93 } ioapics[MAX_IO_APICS];
94 
95 #define mpc_ioapic_ver(id)		ioapics[id].mp_config.apicver
96 
97 int mpc_ioapic_id(int id)
98 {
99 	return ioapics[id].mp_config.apicid;
100 }
101 
102 unsigned int mpc_ioapic_addr(int id)
103 {
104 	return ioapics[id].mp_config.apicaddr;
105 }
106 
107 struct mp_ioapic_gsi *mp_ioapic_gsi_routing(int id)
108 {
109 	return &ioapics[id].gsi_config;
110 }
111 
112 int nr_ioapics;
113 
114 /* The one past the highest gsi number used */
115 u32 gsi_top;
116 
117 /* MP IRQ source entries */
118 struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
119 
120 /* # of MP IRQ source entries */
121 int mp_irq_entries;
122 
123 /* GSI interrupts */
124 static int nr_irqs_gsi = NR_IRQS_LEGACY;
125 
126 #if defined (CONFIG_MCA) || defined (CONFIG_EISA)
127 int mp_bus_id_to_type[MAX_MP_BUSSES];
128 #endif
129 
130 DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
131 
132 int skip_ioapic_setup;
133 
134 /**
135  * disable_ioapic_support() - disables ioapic support at runtime
136  */
137 void disable_ioapic_support(void)
138 {
139 #ifdef CONFIG_PCI
140 	noioapicquirk = 1;
141 	noioapicreroute = -1;
142 #endif
143 	skip_ioapic_setup = 1;
144 }
145 
146 static int __init parse_noapic(char *str)
147 {
148 	/* disable IO-APIC */
149 	disable_ioapic_support();
150 	return 0;
151 }
152 early_param("noapic", parse_noapic);
153 
154 static int io_apic_setup_irq_pin(unsigned int irq, int node,
155 				 struct io_apic_irq_attr *attr);
156 
157 /* Will be called in mpparse/acpi/sfi codes for saving IRQ info */
158 void mp_save_irq(struct mpc_intsrc *m)
159 {
160 	int i;
161 
162 	apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
163 		" IRQ %02x, APIC ID %x, APIC INT %02x\n",
164 		m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbus,
165 		m->srcbusirq, m->dstapic, m->dstirq);
166 
167 	for (i = 0; i < mp_irq_entries; i++) {
168 		if (!memcmp(&mp_irqs[i], m, sizeof(*m)))
169 			return;
170 	}
171 
172 	memcpy(&mp_irqs[mp_irq_entries], m, sizeof(*m));
173 	if (++mp_irq_entries == MAX_IRQ_SOURCES)
174 		panic("Max # of irq sources exceeded!!\n");
175 }
176 
177 struct irq_pin_list {
178 	int apic, pin;
179 	struct irq_pin_list *next;
180 };
181 
182 static struct irq_pin_list *alloc_irq_pin_list(int node)
183 {
184 	return kzalloc_node(sizeof(struct irq_pin_list), GFP_KERNEL, node);
185 }
186 
187 
188 /* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
189 #ifdef CONFIG_SPARSE_IRQ
190 static struct irq_cfg irq_cfgx[NR_IRQS_LEGACY];
191 #else
192 static struct irq_cfg irq_cfgx[NR_IRQS];
193 #endif
194 
195 int __init arch_early_irq_init(void)
196 {
197 	struct irq_cfg *cfg;
198 	int count, node, i;
199 
200 	if (!legacy_pic->nr_legacy_irqs) {
201 		nr_irqs_gsi = 0;
202 		io_apic_irqs = ~0UL;
203 	}
204 
205 	for (i = 0; i < nr_ioapics; i++) {
206 		ioapics[i].saved_registers =
207 			kzalloc(sizeof(struct IO_APIC_route_entry) *
208 				ioapics[i].nr_registers, GFP_KERNEL);
209 		if (!ioapics[i].saved_registers)
210 			pr_err("IOAPIC %d: suspend/resume impossible!\n", i);
211 	}
212 
213 	cfg = irq_cfgx;
214 	count = ARRAY_SIZE(irq_cfgx);
215 	node = cpu_to_node(0);
216 
217 	/* Make sure the legacy interrupts are marked in the bitmap */
218 	irq_reserve_irqs(0, legacy_pic->nr_legacy_irqs);
219 
220 	for (i = 0; i < count; i++) {
221 		irq_set_chip_data(i, &cfg[i]);
222 		zalloc_cpumask_var_node(&cfg[i].domain, GFP_KERNEL, node);
223 		zalloc_cpumask_var_node(&cfg[i].old_domain, GFP_KERNEL, node);
224 		/*
225 		 * For legacy IRQ's, start with assigning irq0 to irq15 to
226 		 * IRQ0_VECTOR to IRQ15_VECTOR on cpu 0.
227 		 */
228 		if (i < legacy_pic->nr_legacy_irqs) {
229 			cfg[i].vector = IRQ0_VECTOR + i;
230 			cpumask_set_cpu(0, cfg[i].domain);
231 		}
232 	}
233 
234 	return 0;
235 }
236 
237 #ifdef CONFIG_SPARSE_IRQ
238 static struct irq_cfg *irq_cfg(unsigned int irq)
239 {
240 	return irq_get_chip_data(irq);
241 }
242 
243 static struct irq_cfg *alloc_irq_cfg(unsigned int irq, int node)
244 {
245 	struct irq_cfg *cfg;
246 
247 	cfg = kzalloc_node(sizeof(*cfg), GFP_KERNEL, node);
248 	if (!cfg)
249 		return NULL;
250 	if (!zalloc_cpumask_var_node(&cfg->domain, GFP_KERNEL, node))
251 		goto out_cfg;
252 	if (!zalloc_cpumask_var_node(&cfg->old_domain, GFP_KERNEL, node))
253 		goto out_domain;
254 	return cfg;
255 out_domain:
256 	free_cpumask_var(cfg->domain);
257 out_cfg:
258 	kfree(cfg);
259 	return NULL;
260 }
261 
262 static void free_irq_cfg(unsigned int at, struct irq_cfg *cfg)
263 {
264 	if (!cfg)
265 		return;
266 	irq_set_chip_data(at, NULL);
267 	free_cpumask_var(cfg->domain);
268 	free_cpumask_var(cfg->old_domain);
269 	kfree(cfg);
270 }
271 
272 #else
273 
274 struct irq_cfg *irq_cfg(unsigned int irq)
275 {
276 	return irq < nr_irqs ? irq_cfgx + irq : NULL;
277 }
278 
279 static struct irq_cfg *alloc_irq_cfg(unsigned int irq, int node)
280 {
281 	return irq_cfgx + irq;
282 }
283 
284 static inline void free_irq_cfg(unsigned int at, struct irq_cfg *cfg) { }
285 
286 #endif
287 
288 static struct irq_cfg *alloc_irq_and_cfg_at(unsigned int at, int node)
289 {
290 	int res = irq_alloc_desc_at(at, node);
291 	struct irq_cfg *cfg;
292 
293 	if (res < 0) {
294 		if (res != -EEXIST)
295 			return NULL;
296 		cfg = irq_get_chip_data(at);
297 		if (cfg)
298 			return cfg;
299 	}
300 
301 	cfg = alloc_irq_cfg(at, node);
302 	if (cfg)
303 		irq_set_chip_data(at, cfg);
304 	else
305 		irq_free_desc(at);
306 	return cfg;
307 }
308 
309 static int alloc_irq_from(unsigned int from, int node)
310 {
311 	return irq_alloc_desc_from(from, node);
312 }
313 
314 static void free_irq_at(unsigned int at, struct irq_cfg *cfg)
315 {
316 	free_irq_cfg(at, cfg);
317 	irq_free_desc(at);
318 }
319 
320 struct io_apic {
321 	unsigned int index;
322 	unsigned int unused[3];
323 	unsigned int data;
324 	unsigned int unused2[11];
325 	unsigned int eoi;
326 };
327 
328 static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
329 {
330 	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
331 		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
332 }
333 
334 static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
335 {
336 	struct io_apic __iomem *io_apic = io_apic_base(apic);
337 	writel(vector, &io_apic->eoi);
338 }
339 
340 static inline unsigned int io_apic_read(unsigned int apic, unsigned int reg)
341 {
342 	struct io_apic __iomem *io_apic = io_apic_base(apic);
343 	writel(reg, &io_apic->index);
344 	return readl(&io_apic->data);
345 }
346 
347 static inline void io_apic_write(unsigned int apic, unsigned int reg, unsigned int value)
348 {
349 	struct io_apic __iomem *io_apic = io_apic_base(apic);
350 	writel(reg, &io_apic->index);
351 	writel(value, &io_apic->data);
352 }
353 
354 /*
355  * Re-write a value: to be used for read-modify-write
356  * cycles where the read already set up the index register.
357  *
358  * Older SiS APIC requires we rewrite the index register
359  */
360 static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned int value)
361 {
362 	struct io_apic __iomem *io_apic = io_apic_base(apic);
363 
364 	if (sis_apic_bug)
365 		writel(reg, &io_apic->index);
366 	writel(value, &io_apic->data);
367 }
368 
369 static bool io_apic_level_ack_pending(struct irq_cfg *cfg)
370 {
371 	struct irq_pin_list *entry;
372 	unsigned long flags;
373 
374 	raw_spin_lock_irqsave(&ioapic_lock, flags);
375 	for_each_irq_pin(entry, cfg->irq_2_pin) {
376 		unsigned int reg;
377 		int pin;
378 
379 		pin = entry->pin;
380 		reg = io_apic_read(entry->apic, 0x10 + pin*2);
381 		/* Is the remote IRR bit set? */
382 		if (reg & IO_APIC_REDIR_REMOTE_IRR) {
383 			raw_spin_unlock_irqrestore(&ioapic_lock, flags);
384 			return true;
385 		}
386 	}
387 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
388 
389 	return false;
390 }
391 
392 union entry_union {
393 	struct { u32 w1, w2; };
394 	struct IO_APIC_route_entry entry;
395 };
396 
397 static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
398 {
399 	union entry_union eu;
400 	unsigned long flags;
401 	raw_spin_lock_irqsave(&ioapic_lock, flags);
402 	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
403 	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
404 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
405 	return eu.entry;
406 }
407 
408 /*
409  * When we write a new IO APIC routing entry, we need to write the high
410  * word first! If the mask bit in the low word is clear, we will enable
411  * the interrupt, and we need to make sure the entry is fully populated
412  * before that happens.
413  */
414 static void
415 __ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
416 {
417 	union entry_union eu = {{0, 0}};
418 
419 	eu.entry = e;
420 	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
421 	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
422 }
423 
424 static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
425 {
426 	unsigned long flags;
427 	raw_spin_lock_irqsave(&ioapic_lock, flags);
428 	__ioapic_write_entry(apic, pin, e);
429 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
430 }
431 
432 /*
433  * When we mask an IO APIC routing entry, we need to write the low
434  * word first, in order to set the mask bit before we change the
435  * high bits!
436  */
437 static void ioapic_mask_entry(int apic, int pin)
438 {
439 	unsigned long flags;
440 	union entry_union eu = { .entry.mask = 1 };
441 
442 	raw_spin_lock_irqsave(&ioapic_lock, flags);
443 	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
444 	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
445 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
446 }
447 
448 /*
449  * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
450  * shared ISA-space IRQs, so we have to support them. We are super
451  * fast in the common case, and fast for shared ISA-space IRQs.
452  */
453 static int
454 __add_pin_to_irq_node(struct irq_cfg *cfg, int node, int apic, int pin)
455 {
456 	struct irq_pin_list **last, *entry;
457 
458 	/* don't allow duplicates */
459 	last = &cfg->irq_2_pin;
460 	for_each_irq_pin(entry, cfg->irq_2_pin) {
461 		if (entry->apic == apic && entry->pin == pin)
462 			return 0;
463 		last = &entry->next;
464 	}
465 
466 	entry = alloc_irq_pin_list(node);
467 	if (!entry) {
468 		printk(KERN_ERR "can not alloc irq_pin_list (%d,%d,%d)\n",
469 				node, apic, pin);
470 		return -ENOMEM;
471 	}
472 	entry->apic = apic;
473 	entry->pin = pin;
474 
475 	*last = entry;
476 	return 0;
477 }
478 
479 static void add_pin_to_irq_node(struct irq_cfg *cfg, int node, int apic, int pin)
480 {
481 	if (__add_pin_to_irq_node(cfg, node, apic, pin))
482 		panic("IO-APIC: failed to add irq-pin. Can not proceed\n");
483 }
484 
485 /*
486  * Reroute an IRQ to a different pin.
487  */
488 static void __init replace_pin_at_irq_node(struct irq_cfg *cfg, int node,
489 					   int oldapic, int oldpin,
490 					   int newapic, int newpin)
491 {
492 	struct irq_pin_list *entry;
493 
494 	for_each_irq_pin(entry, cfg->irq_2_pin) {
495 		if (entry->apic == oldapic && entry->pin == oldpin) {
496 			entry->apic = newapic;
497 			entry->pin = newpin;
498 			/* every one is different, right? */
499 			return;
500 		}
501 	}
502 
503 	/* old apic/pin didn't exist, so just add new ones */
504 	add_pin_to_irq_node(cfg, node, newapic, newpin);
505 }
506 
507 static void __io_apic_modify_irq(struct irq_pin_list *entry,
508 				 int mask_and, int mask_or,
509 				 void (*final)(struct irq_pin_list *entry))
510 {
511 	unsigned int reg, pin;
512 
513 	pin = entry->pin;
514 	reg = io_apic_read(entry->apic, 0x10 + pin * 2);
515 	reg &= mask_and;
516 	reg |= mask_or;
517 	io_apic_modify(entry->apic, 0x10 + pin * 2, reg);
518 	if (final)
519 		final(entry);
520 }
521 
522 static void io_apic_modify_irq(struct irq_cfg *cfg,
523 			       int mask_and, int mask_or,
524 			       void (*final)(struct irq_pin_list *entry))
525 {
526 	struct irq_pin_list *entry;
527 
528 	for_each_irq_pin(entry, cfg->irq_2_pin)
529 		__io_apic_modify_irq(entry, mask_and, mask_or, final);
530 }
531 
532 static void __mask_and_edge_IO_APIC_irq(struct irq_pin_list *entry)
533 {
534 	__io_apic_modify_irq(entry, ~IO_APIC_REDIR_LEVEL_TRIGGER,
535 			     IO_APIC_REDIR_MASKED, NULL);
536 }
537 
538 static void __unmask_and_level_IO_APIC_irq(struct irq_pin_list *entry)
539 {
540 	__io_apic_modify_irq(entry, ~IO_APIC_REDIR_MASKED,
541 			     IO_APIC_REDIR_LEVEL_TRIGGER, NULL);
542 }
543 
544 static void io_apic_sync(struct irq_pin_list *entry)
545 {
546 	/*
547 	 * Synchronize the IO-APIC and the CPU by doing
548 	 * a dummy read from the IO-APIC
549 	 */
550 	struct io_apic __iomem *io_apic;
551 	io_apic = io_apic_base(entry->apic);
552 	readl(&io_apic->data);
553 }
554 
555 static void mask_ioapic(struct irq_cfg *cfg)
556 {
557 	unsigned long flags;
558 
559 	raw_spin_lock_irqsave(&ioapic_lock, flags);
560 	io_apic_modify_irq(cfg, ~0, IO_APIC_REDIR_MASKED, &io_apic_sync);
561 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
562 }
563 
564 static void mask_ioapic_irq(struct irq_data *data)
565 {
566 	mask_ioapic(data->chip_data);
567 }
568 
569 static void __unmask_ioapic(struct irq_cfg *cfg)
570 {
571 	io_apic_modify_irq(cfg, ~IO_APIC_REDIR_MASKED, 0, NULL);
572 }
573 
574 static void unmask_ioapic(struct irq_cfg *cfg)
575 {
576 	unsigned long flags;
577 
578 	raw_spin_lock_irqsave(&ioapic_lock, flags);
579 	__unmask_ioapic(cfg);
580 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
581 }
582 
583 static void unmask_ioapic_irq(struct irq_data *data)
584 {
585 	unmask_ioapic(data->chip_data);
586 }
587 
588 static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
589 {
590 	struct IO_APIC_route_entry entry;
591 
592 	/* Check delivery_mode to be sure we're not clearing an SMI pin */
593 	entry = ioapic_read_entry(apic, pin);
594 	if (entry.delivery_mode == dest_SMI)
595 		return;
596 	/*
597 	 * Disable it in the IO-APIC irq-routing table:
598 	 */
599 	ioapic_mask_entry(apic, pin);
600 }
601 
602 static void clear_IO_APIC (void)
603 {
604 	int apic, pin;
605 
606 	for (apic = 0; apic < nr_ioapics; apic++)
607 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++)
608 			clear_IO_APIC_pin(apic, pin);
609 }
610 
611 #ifdef CONFIG_X86_32
612 /*
613  * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
614  * specific CPU-side IRQs.
615  */
616 
617 #define MAX_PIRQS 8
618 static int pirq_entries[MAX_PIRQS] = {
619 	[0 ... MAX_PIRQS - 1] = -1
620 };
621 
622 static int __init ioapic_pirq_setup(char *str)
623 {
624 	int i, max;
625 	int ints[MAX_PIRQS+1];
626 
627 	get_options(str, ARRAY_SIZE(ints), ints);
628 
629 	apic_printk(APIC_VERBOSE, KERN_INFO
630 			"PIRQ redirection, working around broken MP-BIOS.\n");
631 	max = MAX_PIRQS;
632 	if (ints[0] < MAX_PIRQS)
633 		max = ints[0];
634 
635 	for (i = 0; i < max; i++) {
636 		apic_printk(APIC_VERBOSE, KERN_DEBUG
637 				"... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
638 		/*
639 		 * PIRQs are mapped upside down, usually.
640 		 */
641 		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
642 	}
643 	return 1;
644 }
645 
646 __setup("pirq=", ioapic_pirq_setup);
647 #endif /* CONFIG_X86_32 */
648 
649 /*
650  * Saves all the IO-APIC RTE's
651  */
652 int save_ioapic_entries(void)
653 {
654 	int apic, pin;
655 	int err = 0;
656 
657 	for (apic = 0; apic < nr_ioapics; apic++) {
658 		if (!ioapics[apic].saved_registers) {
659 			err = -ENOMEM;
660 			continue;
661 		}
662 
663 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++)
664 			ioapics[apic].saved_registers[pin] =
665 				ioapic_read_entry(apic, pin);
666 	}
667 
668 	return err;
669 }
670 
671 /*
672  * Mask all IO APIC entries.
673  */
674 void mask_ioapic_entries(void)
675 {
676 	int apic, pin;
677 
678 	for (apic = 0; apic < nr_ioapics; apic++) {
679 		if (!ioapics[apic].saved_registers)
680 			continue;
681 
682 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
683 			struct IO_APIC_route_entry entry;
684 
685 			entry = ioapics[apic].saved_registers[pin];
686 			if (!entry.mask) {
687 				entry.mask = 1;
688 				ioapic_write_entry(apic, pin, entry);
689 			}
690 		}
691 	}
692 }
693 
694 /*
695  * Restore IO APIC entries which was saved in the ioapic structure.
696  */
697 int restore_ioapic_entries(void)
698 {
699 	int apic, pin;
700 
701 	for (apic = 0; apic < nr_ioapics; apic++) {
702 		if (!ioapics[apic].saved_registers)
703 			continue;
704 
705 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++)
706 			ioapic_write_entry(apic, pin,
707 					   ioapics[apic].saved_registers[pin]);
708 	}
709 	return 0;
710 }
711 
712 /*
713  * Find the IRQ entry number of a certain pin.
714  */
715 static int find_irq_entry(int apic, int pin, int type)
716 {
717 	int i;
718 
719 	for (i = 0; i < mp_irq_entries; i++)
720 		if (mp_irqs[i].irqtype == type &&
721 		    (mp_irqs[i].dstapic == mpc_ioapic_id(apic) ||
722 		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
723 		    mp_irqs[i].dstirq == pin)
724 			return i;
725 
726 	return -1;
727 }
728 
729 /*
730  * Find the pin to which IRQ[irq] (ISA) is connected
731  */
732 static int __init find_isa_irq_pin(int irq, int type)
733 {
734 	int i;
735 
736 	for (i = 0; i < mp_irq_entries; i++) {
737 		int lbus = mp_irqs[i].srcbus;
738 
739 		if (test_bit(lbus, mp_bus_not_pci) &&
740 		    (mp_irqs[i].irqtype == type) &&
741 		    (mp_irqs[i].srcbusirq == irq))
742 
743 			return mp_irqs[i].dstirq;
744 	}
745 	return -1;
746 }
747 
748 static int __init find_isa_irq_apic(int irq, int type)
749 {
750 	int i;
751 
752 	for (i = 0; i < mp_irq_entries; i++) {
753 		int lbus = mp_irqs[i].srcbus;
754 
755 		if (test_bit(lbus, mp_bus_not_pci) &&
756 		    (mp_irqs[i].irqtype == type) &&
757 		    (mp_irqs[i].srcbusirq == irq))
758 			break;
759 	}
760 	if (i < mp_irq_entries) {
761 		int apic;
762 		for(apic = 0; apic < nr_ioapics; apic++) {
763 			if (mpc_ioapic_id(apic) == mp_irqs[i].dstapic)
764 				return apic;
765 		}
766 	}
767 
768 	return -1;
769 }
770 
771 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
772 /*
773  * EISA Edge/Level control register, ELCR
774  */
775 static int EISA_ELCR(unsigned int irq)
776 {
777 	if (irq < legacy_pic->nr_legacy_irqs) {
778 		unsigned int port = 0x4d0 + (irq >> 3);
779 		return (inb(port) >> (irq & 7)) & 1;
780 	}
781 	apic_printk(APIC_VERBOSE, KERN_INFO
782 			"Broken MPtable reports ISA irq %d\n", irq);
783 	return 0;
784 }
785 
786 #endif
787 
788 /* ISA interrupts are always polarity zero edge triggered,
789  * when listed as conforming in the MP table. */
790 
791 #define default_ISA_trigger(idx)	(0)
792 #define default_ISA_polarity(idx)	(0)
793 
794 /* EISA interrupts are always polarity zero and can be edge or level
795  * trigger depending on the ELCR value.  If an interrupt is listed as
796  * EISA conforming in the MP table, that means its trigger type must
797  * be read in from the ELCR */
798 
799 #define default_EISA_trigger(idx)	(EISA_ELCR(mp_irqs[idx].srcbusirq))
800 #define default_EISA_polarity(idx)	default_ISA_polarity(idx)
801 
802 /* PCI interrupts are always polarity one level triggered,
803  * when listed as conforming in the MP table. */
804 
805 #define default_PCI_trigger(idx)	(1)
806 #define default_PCI_polarity(idx)	(1)
807 
808 /* MCA interrupts are always polarity zero level triggered,
809  * when listed as conforming in the MP table. */
810 
811 #define default_MCA_trigger(idx)	(1)
812 #define default_MCA_polarity(idx)	default_ISA_polarity(idx)
813 
814 static int irq_polarity(int idx)
815 {
816 	int bus = mp_irqs[idx].srcbus;
817 	int polarity;
818 
819 	/*
820 	 * Determine IRQ line polarity (high active or low active):
821 	 */
822 	switch (mp_irqs[idx].irqflag & 3)
823 	{
824 		case 0: /* conforms, ie. bus-type dependent polarity */
825 			if (test_bit(bus, mp_bus_not_pci))
826 				polarity = default_ISA_polarity(idx);
827 			else
828 				polarity = default_PCI_polarity(idx);
829 			break;
830 		case 1: /* high active */
831 		{
832 			polarity = 0;
833 			break;
834 		}
835 		case 2: /* reserved */
836 		{
837 			printk(KERN_WARNING "broken BIOS!!\n");
838 			polarity = 1;
839 			break;
840 		}
841 		case 3: /* low active */
842 		{
843 			polarity = 1;
844 			break;
845 		}
846 		default: /* invalid */
847 		{
848 			printk(KERN_WARNING "broken BIOS!!\n");
849 			polarity = 1;
850 			break;
851 		}
852 	}
853 	return polarity;
854 }
855 
856 static int irq_trigger(int idx)
857 {
858 	int bus = mp_irqs[idx].srcbus;
859 	int trigger;
860 
861 	/*
862 	 * Determine IRQ trigger mode (edge or level sensitive):
863 	 */
864 	switch ((mp_irqs[idx].irqflag>>2) & 3)
865 	{
866 		case 0: /* conforms, ie. bus-type dependent */
867 			if (test_bit(bus, mp_bus_not_pci))
868 				trigger = default_ISA_trigger(idx);
869 			else
870 				trigger = default_PCI_trigger(idx);
871 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
872 			switch (mp_bus_id_to_type[bus]) {
873 				case MP_BUS_ISA: /* ISA pin */
874 				{
875 					/* set before the switch */
876 					break;
877 				}
878 				case MP_BUS_EISA: /* EISA pin */
879 				{
880 					trigger = default_EISA_trigger(idx);
881 					break;
882 				}
883 				case MP_BUS_PCI: /* PCI pin */
884 				{
885 					/* set before the switch */
886 					break;
887 				}
888 				case MP_BUS_MCA: /* MCA pin */
889 				{
890 					trigger = default_MCA_trigger(idx);
891 					break;
892 				}
893 				default:
894 				{
895 					printk(KERN_WARNING "broken BIOS!!\n");
896 					trigger = 1;
897 					break;
898 				}
899 			}
900 #endif
901 			break;
902 		case 1: /* edge */
903 		{
904 			trigger = 0;
905 			break;
906 		}
907 		case 2: /* reserved */
908 		{
909 			printk(KERN_WARNING "broken BIOS!!\n");
910 			trigger = 1;
911 			break;
912 		}
913 		case 3: /* level */
914 		{
915 			trigger = 1;
916 			break;
917 		}
918 		default: /* invalid */
919 		{
920 			printk(KERN_WARNING "broken BIOS!!\n");
921 			trigger = 0;
922 			break;
923 		}
924 	}
925 	return trigger;
926 }
927 
928 static int pin_2_irq(int idx, int apic, int pin)
929 {
930 	int irq;
931 	int bus = mp_irqs[idx].srcbus;
932 	struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(apic);
933 
934 	/*
935 	 * Debugging check, we are in big trouble if this message pops up!
936 	 */
937 	if (mp_irqs[idx].dstirq != pin)
938 		printk(KERN_ERR "broken BIOS or MPTABLE parser, ayiee!!\n");
939 
940 	if (test_bit(bus, mp_bus_not_pci)) {
941 		irq = mp_irqs[idx].srcbusirq;
942 	} else {
943 		u32 gsi = gsi_cfg->gsi_base + pin;
944 
945 		if (gsi >= NR_IRQS_LEGACY)
946 			irq = gsi;
947 		else
948 			irq = gsi_top + gsi;
949 	}
950 
951 #ifdef CONFIG_X86_32
952 	/*
953 	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
954 	 */
955 	if ((pin >= 16) && (pin <= 23)) {
956 		if (pirq_entries[pin-16] != -1) {
957 			if (!pirq_entries[pin-16]) {
958 				apic_printk(APIC_VERBOSE, KERN_DEBUG
959 						"disabling PIRQ%d\n", pin-16);
960 			} else {
961 				irq = pirq_entries[pin-16];
962 				apic_printk(APIC_VERBOSE, KERN_DEBUG
963 						"using PIRQ%d -> IRQ %d\n",
964 						pin-16, irq);
965 			}
966 		}
967 	}
968 #endif
969 
970 	return irq;
971 }
972 
973 /*
974  * Find a specific PCI IRQ entry.
975  * Not an __init, possibly needed by modules
976  */
977 int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin,
978 				struct io_apic_irq_attr *irq_attr)
979 {
980 	int apic, i, best_guess = -1;
981 
982 	apic_printk(APIC_DEBUG,
983 		    "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
984 		    bus, slot, pin);
985 	if (test_bit(bus, mp_bus_not_pci)) {
986 		apic_printk(APIC_VERBOSE,
987 			    "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
988 		return -1;
989 	}
990 	for (i = 0; i < mp_irq_entries; i++) {
991 		int lbus = mp_irqs[i].srcbus;
992 
993 		for (apic = 0; apic < nr_ioapics; apic++)
994 			if (mpc_ioapic_id(apic) == mp_irqs[i].dstapic ||
995 			    mp_irqs[i].dstapic == MP_APIC_ALL)
996 				break;
997 
998 		if (!test_bit(lbus, mp_bus_not_pci) &&
999 		    !mp_irqs[i].irqtype &&
1000 		    (bus == lbus) &&
1001 		    (slot == ((mp_irqs[i].srcbusirq >> 2) & 0x1f))) {
1002 			int irq = pin_2_irq(i, apic, mp_irqs[i].dstirq);
1003 
1004 			if (!(apic || IO_APIC_IRQ(irq)))
1005 				continue;
1006 
1007 			if (pin == (mp_irqs[i].srcbusirq & 3)) {
1008 				set_io_apic_irq_attr(irq_attr, apic,
1009 						     mp_irqs[i].dstirq,
1010 						     irq_trigger(i),
1011 						     irq_polarity(i));
1012 				return irq;
1013 			}
1014 			/*
1015 			 * Use the first all-but-pin matching entry as a
1016 			 * best-guess fuzzy result for broken mptables.
1017 			 */
1018 			if (best_guess < 0) {
1019 				set_io_apic_irq_attr(irq_attr, apic,
1020 						     mp_irqs[i].dstirq,
1021 						     irq_trigger(i),
1022 						     irq_polarity(i));
1023 				best_guess = irq;
1024 			}
1025 		}
1026 	}
1027 	return best_guess;
1028 }
1029 EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
1030 
1031 void lock_vector_lock(void)
1032 {
1033 	/* Used to the online set of cpus does not change
1034 	 * during assign_irq_vector.
1035 	 */
1036 	raw_spin_lock(&vector_lock);
1037 }
1038 
1039 void unlock_vector_lock(void)
1040 {
1041 	raw_spin_unlock(&vector_lock);
1042 }
1043 
1044 static int
1045 __assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
1046 {
1047 	/*
1048 	 * NOTE! The local APIC isn't very good at handling
1049 	 * multiple interrupts at the same interrupt level.
1050 	 * As the interrupt level is determined by taking the
1051 	 * vector number and shifting that right by 4, we
1052 	 * want to spread these out a bit so that they don't
1053 	 * all fall in the same interrupt level.
1054 	 *
1055 	 * Also, we've got to be careful not to trash gate
1056 	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
1057 	 */
1058 	static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
1059 	static int current_offset = VECTOR_OFFSET_START % 8;
1060 	unsigned int old_vector;
1061 	int cpu, err;
1062 	cpumask_var_t tmp_mask;
1063 
1064 	if (cfg->move_in_progress)
1065 		return -EBUSY;
1066 
1067 	if (!alloc_cpumask_var(&tmp_mask, GFP_ATOMIC))
1068 		return -ENOMEM;
1069 
1070 	old_vector = cfg->vector;
1071 	if (old_vector) {
1072 		cpumask_and(tmp_mask, mask, cpu_online_mask);
1073 		cpumask_and(tmp_mask, cfg->domain, tmp_mask);
1074 		if (!cpumask_empty(tmp_mask)) {
1075 			free_cpumask_var(tmp_mask);
1076 			return 0;
1077 		}
1078 	}
1079 
1080 	/* Only try and allocate irqs on cpus that are present */
1081 	err = -ENOSPC;
1082 	for_each_cpu_and(cpu, mask, cpu_online_mask) {
1083 		int new_cpu;
1084 		int vector, offset;
1085 
1086 		apic->vector_allocation_domain(cpu, tmp_mask);
1087 
1088 		vector = current_vector;
1089 		offset = current_offset;
1090 next:
1091 		vector += 8;
1092 		if (vector >= first_system_vector) {
1093 			/* If out of vectors on large boxen, must share them. */
1094 			offset = (offset + 1) % 8;
1095 			vector = FIRST_EXTERNAL_VECTOR + offset;
1096 		}
1097 		if (unlikely(current_vector == vector))
1098 			continue;
1099 
1100 		if (test_bit(vector, used_vectors))
1101 			goto next;
1102 
1103 		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
1104 			if (per_cpu(vector_irq, new_cpu)[vector] != -1)
1105 				goto next;
1106 		/* Found one! */
1107 		current_vector = vector;
1108 		current_offset = offset;
1109 		if (old_vector) {
1110 			cfg->move_in_progress = 1;
1111 			cpumask_copy(cfg->old_domain, cfg->domain);
1112 		}
1113 		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
1114 			per_cpu(vector_irq, new_cpu)[vector] = irq;
1115 		cfg->vector = vector;
1116 		cpumask_copy(cfg->domain, tmp_mask);
1117 		err = 0;
1118 		break;
1119 	}
1120 	free_cpumask_var(tmp_mask);
1121 	return err;
1122 }
1123 
1124 int assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
1125 {
1126 	int err;
1127 	unsigned long flags;
1128 
1129 	raw_spin_lock_irqsave(&vector_lock, flags);
1130 	err = __assign_irq_vector(irq, cfg, mask);
1131 	raw_spin_unlock_irqrestore(&vector_lock, flags);
1132 	return err;
1133 }
1134 
1135 static void __clear_irq_vector(int irq, struct irq_cfg *cfg)
1136 {
1137 	int cpu, vector;
1138 
1139 	BUG_ON(!cfg->vector);
1140 
1141 	vector = cfg->vector;
1142 	for_each_cpu_and(cpu, cfg->domain, cpu_online_mask)
1143 		per_cpu(vector_irq, cpu)[vector] = -1;
1144 
1145 	cfg->vector = 0;
1146 	cpumask_clear(cfg->domain);
1147 
1148 	if (likely(!cfg->move_in_progress))
1149 		return;
1150 	for_each_cpu_and(cpu, cfg->old_domain, cpu_online_mask) {
1151 		for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
1152 								vector++) {
1153 			if (per_cpu(vector_irq, cpu)[vector] != irq)
1154 				continue;
1155 			per_cpu(vector_irq, cpu)[vector] = -1;
1156 			break;
1157 		}
1158 	}
1159 	cfg->move_in_progress = 0;
1160 }
1161 
1162 void __setup_vector_irq(int cpu)
1163 {
1164 	/* Initialize vector_irq on a new cpu */
1165 	int irq, vector;
1166 	struct irq_cfg *cfg;
1167 
1168 	/*
1169 	 * vector_lock will make sure that we don't run into irq vector
1170 	 * assignments that might be happening on another cpu in parallel,
1171 	 * while we setup our initial vector to irq mappings.
1172 	 */
1173 	raw_spin_lock(&vector_lock);
1174 	/* Mark the inuse vectors */
1175 	for_each_active_irq(irq) {
1176 		cfg = irq_get_chip_data(irq);
1177 		if (!cfg)
1178 			continue;
1179 		/*
1180 		 * If it is a legacy IRQ handled by the legacy PIC, this cpu
1181 		 * will be part of the irq_cfg's domain.
1182 		 */
1183 		if (irq < legacy_pic->nr_legacy_irqs && !IO_APIC_IRQ(irq))
1184 			cpumask_set_cpu(cpu, cfg->domain);
1185 
1186 		if (!cpumask_test_cpu(cpu, cfg->domain))
1187 			continue;
1188 		vector = cfg->vector;
1189 		per_cpu(vector_irq, cpu)[vector] = irq;
1190 	}
1191 	/* Mark the free vectors */
1192 	for (vector = 0; vector < NR_VECTORS; ++vector) {
1193 		irq = per_cpu(vector_irq, cpu)[vector];
1194 		if (irq < 0)
1195 			continue;
1196 
1197 		cfg = irq_cfg(irq);
1198 		if (!cpumask_test_cpu(cpu, cfg->domain))
1199 			per_cpu(vector_irq, cpu)[vector] = -1;
1200 	}
1201 	raw_spin_unlock(&vector_lock);
1202 }
1203 
1204 static struct irq_chip ioapic_chip;
1205 static struct irq_chip ir_ioapic_chip;
1206 
1207 #ifdef CONFIG_X86_32
1208 static inline int IO_APIC_irq_trigger(int irq)
1209 {
1210 	int apic, idx, pin;
1211 
1212 	for (apic = 0; apic < nr_ioapics; apic++) {
1213 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
1214 			idx = find_irq_entry(apic, pin, mp_INT);
1215 			if ((idx != -1) && (irq == pin_2_irq(idx, apic, pin)))
1216 				return irq_trigger(idx);
1217 		}
1218 	}
1219 	/*
1220          * nonexistent IRQs are edge default
1221          */
1222 	return 0;
1223 }
1224 #else
1225 static inline int IO_APIC_irq_trigger(int irq)
1226 {
1227 	return 1;
1228 }
1229 #endif
1230 
1231 static void ioapic_register_intr(unsigned int irq, struct irq_cfg *cfg,
1232 				 unsigned long trigger)
1233 {
1234 	struct irq_chip *chip = &ioapic_chip;
1235 	irq_flow_handler_t hdl;
1236 	bool fasteoi;
1237 
1238 	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
1239 	    trigger == IOAPIC_LEVEL) {
1240 		irq_set_status_flags(irq, IRQ_LEVEL);
1241 		fasteoi = true;
1242 	} else {
1243 		irq_clear_status_flags(irq, IRQ_LEVEL);
1244 		fasteoi = false;
1245 	}
1246 
1247 	if (irq_remapped(cfg)) {
1248 		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
1249 		chip = &ir_ioapic_chip;
1250 		fasteoi = trigger != 0;
1251 	}
1252 
1253 	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
1254 	irq_set_chip_and_handler_name(irq, chip, hdl,
1255 				      fasteoi ? "fasteoi" : "edge");
1256 }
1257 
1258 static int setup_ioapic_entry(int apic_id, int irq,
1259 			      struct IO_APIC_route_entry *entry,
1260 			      unsigned int destination, int trigger,
1261 			      int polarity, int vector, int pin)
1262 {
1263 	/*
1264 	 * add it to the IO-APIC irq-routing table:
1265 	 */
1266 	memset(entry,0,sizeof(*entry));
1267 
1268 	if (intr_remapping_enabled) {
1269 		struct intel_iommu *iommu = map_ioapic_to_ir(apic_id);
1270 		struct irte irte;
1271 		struct IR_IO_APIC_route_entry *ir_entry =
1272 			(struct IR_IO_APIC_route_entry *) entry;
1273 		int index;
1274 
1275 		if (!iommu)
1276 			panic("No mapping iommu for ioapic %d\n", apic_id);
1277 
1278 		index = alloc_irte(iommu, irq, 1);
1279 		if (index < 0)
1280 			panic("Failed to allocate IRTE for ioapic %d\n", apic_id);
1281 
1282 		prepare_irte(&irte, vector, destination);
1283 
1284 		/* Set source-id of interrupt request */
1285 		set_ioapic_sid(&irte, apic_id);
1286 
1287 		modify_irte(irq, &irte);
1288 
1289 		ir_entry->index2 = (index >> 15) & 0x1;
1290 		ir_entry->zero = 0;
1291 		ir_entry->format = 1;
1292 		ir_entry->index = (index & 0x7fff);
1293 		/*
1294 		 * IO-APIC RTE will be configured with virtual vector.
1295 		 * irq handler will do the explicit EOI to the io-apic.
1296 		 */
1297 		ir_entry->vector = pin;
1298 	} else {
1299 		entry->delivery_mode = apic->irq_delivery_mode;
1300 		entry->dest_mode = apic->irq_dest_mode;
1301 		entry->dest = destination;
1302 		entry->vector = vector;
1303 	}
1304 
1305 	entry->mask = 0;				/* enable IRQ */
1306 	entry->trigger = trigger;
1307 	entry->polarity = polarity;
1308 
1309 	/* Mask level triggered irqs.
1310 	 * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
1311 	 */
1312 	if (trigger)
1313 		entry->mask = 1;
1314 	return 0;
1315 }
1316 
1317 static void setup_ioapic_irq(int apic_id, int pin, unsigned int irq,
1318 			     struct irq_cfg *cfg, int trigger, int polarity)
1319 {
1320 	struct IO_APIC_route_entry entry;
1321 	unsigned int dest;
1322 
1323 	if (!IO_APIC_IRQ(irq))
1324 		return;
1325 	/*
1326 	 * For legacy irqs, cfg->domain starts with cpu 0 for legacy
1327 	 * controllers like 8259. Now that IO-APIC can handle this irq, update
1328 	 * the cfg->domain.
1329 	 */
1330 	if (irq < legacy_pic->nr_legacy_irqs && cpumask_test_cpu(0, cfg->domain))
1331 		apic->vector_allocation_domain(0, cfg->domain);
1332 
1333 	if (assign_irq_vector(irq, cfg, apic->target_cpus()))
1334 		return;
1335 
1336 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
1337 
1338 	apic_printk(APIC_VERBOSE,KERN_DEBUG
1339 		    "IOAPIC[%d]: Set routing entry (%d-%d -> 0x%x -> "
1340 		    "IRQ %d Mode:%i Active:%i)\n",
1341 		    apic_id, mpc_ioapic_id(apic_id), pin, cfg->vector,
1342 		    irq, trigger, polarity);
1343 
1344 
1345 	if (setup_ioapic_entry(mpc_ioapic_id(apic_id), irq, &entry,
1346 			       dest, trigger, polarity, cfg->vector, pin)) {
1347 		printk("Failed to setup ioapic entry for ioapic  %d, pin %d\n",
1348 		       mpc_ioapic_id(apic_id), pin);
1349 		__clear_irq_vector(irq, cfg);
1350 		return;
1351 	}
1352 
1353 	ioapic_register_intr(irq, cfg, trigger);
1354 	if (irq < legacy_pic->nr_legacy_irqs)
1355 		legacy_pic->mask(irq);
1356 
1357 	ioapic_write_entry(apic_id, pin, entry);
1358 }
1359 
1360 static bool __init io_apic_pin_not_connected(int idx, int apic_id, int pin)
1361 {
1362 	if (idx != -1)
1363 		return false;
1364 
1365 	apic_printk(APIC_VERBOSE, KERN_DEBUG " apic %d pin %d not connected\n",
1366 		    mpc_ioapic_id(apic_id), pin);
1367 	return true;
1368 }
1369 
1370 static void __init __io_apic_setup_irqs(unsigned int apic_id)
1371 {
1372 	int idx, node = cpu_to_node(0);
1373 	struct io_apic_irq_attr attr;
1374 	unsigned int pin, irq;
1375 
1376 	for (pin = 0; pin < ioapics[apic_id].nr_registers; pin++) {
1377 		idx = find_irq_entry(apic_id, pin, mp_INT);
1378 		if (io_apic_pin_not_connected(idx, apic_id, pin))
1379 			continue;
1380 
1381 		irq = pin_2_irq(idx, apic_id, pin);
1382 
1383 		if ((apic_id > 0) && (irq > 16))
1384 			continue;
1385 
1386 		/*
1387 		 * Skip the timer IRQ if there's a quirk handler
1388 		 * installed and if it returns 1:
1389 		 */
1390 		if (apic->multi_timer_check &&
1391 		    apic->multi_timer_check(apic_id, irq))
1392 			continue;
1393 
1394 		set_io_apic_irq_attr(&attr, apic_id, pin, irq_trigger(idx),
1395 				     irq_polarity(idx));
1396 
1397 		io_apic_setup_irq_pin(irq, node, &attr);
1398 	}
1399 }
1400 
1401 static void __init setup_IO_APIC_irqs(void)
1402 {
1403 	unsigned int apic_id;
1404 
1405 	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1406 
1407 	for (apic_id = 0; apic_id < nr_ioapics; apic_id++)
1408 		__io_apic_setup_irqs(apic_id);
1409 }
1410 
1411 /*
1412  * for the gsit that is not in first ioapic
1413  * but could not use acpi_register_gsi()
1414  * like some special sci in IBM x3330
1415  */
1416 void setup_IO_APIC_irq_extra(u32 gsi)
1417 {
1418 	int apic_id = 0, pin, idx, irq, node = cpu_to_node(0);
1419 	struct io_apic_irq_attr attr;
1420 
1421 	/*
1422 	 * Convert 'gsi' to 'ioapic.pin'.
1423 	 */
1424 	apic_id = mp_find_ioapic(gsi);
1425 	if (apic_id < 0)
1426 		return;
1427 
1428 	pin = mp_find_ioapic_pin(apic_id, gsi);
1429 	idx = find_irq_entry(apic_id, pin, mp_INT);
1430 	if (idx == -1)
1431 		return;
1432 
1433 	irq = pin_2_irq(idx, apic_id, pin);
1434 
1435 	/* Only handle the non legacy irqs on secondary ioapics */
1436 	if (apic_id == 0 || irq < NR_IRQS_LEGACY)
1437 		return;
1438 
1439 	set_io_apic_irq_attr(&attr, apic_id, pin, irq_trigger(idx),
1440 			     irq_polarity(idx));
1441 
1442 	io_apic_setup_irq_pin_once(irq, node, &attr);
1443 }
1444 
1445 /*
1446  * Set up the timer pin, possibly with the 8259A-master behind.
1447  */
1448 static void __init setup_timer_IRQ0_pin(unsigned int apic_id, unsigned int pin,
1449 					int vector)
1450 {
1451 	struct IO_APIC_route_entry entry;
1452 
1453 	if (intr_remapping_enabled)
1454 		return;
1455 
1456 	memset(&entry, 0, sizeof(entry));
1457 
1458 	/*
1459 	 * We use logical delivery to get the timer IRQ
1460 	 * to the first CPU.
1461 	 */
1462 	entry.dest_mode = apic->irq_dest_mode;
1463 	entry.mask = 0;			/* don't mask IRQ for edge */
1464 	entry.dest = apic->cpu_mask_to_apicid(apic->target_cpus());
1465 	entry.delivery_mode = apic->irq_delivery_mode;
1466 	entry.polarity = 0;
1467 	entry.trigger = 0;
1468 	entry.vector = vector;
1469 
1470 	/*
1471 	 * The timer IRQ doesn't have to know that behind the
1472 	 * scene we may have a 8259A-master in AEOI mode ...
1473 	 */
1474 	irq_set_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq,
1475 				      "edge");
1476 
1477 	/*
1478 	 * Add it to the IO-APIC irq-routing table:
1479 	 */
1480 	ioapic_write_entry(apic_id, pin, entry);
1481 }
1482 
1483 
1484 __apicdebuginit(void) print_IO_APIC(void)
1485 {
1486 	int apic, i;
1487 	union IO_APIC_reg_00 reg_00;
1488 	union IO_APIC_reg_01 reg_01;
1489 	union IO_APIC_reg_02 reg_02;
1490 	union IO_APIC_reg_03 reg_03;
1491 	unsigned long flags;
1492 	struct irq_cfg *cfg;
1493 	unsigned int irq;
1494 
1495 	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1496 	for (i = 0; i < nr_ioapics; i++)
1497 		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1498 		       mpc_ioapic_id(i), ioapics[i].nr_registers);
1499 
1500 	/*
1501 	 * We are a bit conservative about what we expect.  We have to
1502 	 * know about every hardware change ASAP.
1503 	 */
1504 	printk(KERN_INFO "testing the IO APIC.......................\n");
1505 
1506 	for (apic = 0; apic < nr_ioapics; apic++) {
1507 
1508 	raw_spin_lock_irqsave(&ioapic_lock, flags);
1509 	reg_00.raw = io_apic_read(apic, 0);
1510 	reg_01.raw = io_apic_read(apic, 1);
1511 	if (reg_01.bits.version >= 0x10)
1512 		reg_02.raw = io_apic_read(apic, 2);
1513 	if (reg_01.bits.version >= 0x20)
1514 		reg_03.raw = io_apic_read(apic, 3);
1515 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1516 
1517 	printk("\n");
1518 	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(apic));
1519 	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1520 	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1521 	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1522 	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1523 
1524 	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
1525 	printk(KERN_DEBUG ".......     : max redirection entries: %04X\n", reg_01.bits.entries);
1526 
1527 	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1528 	printk(KERN_DEBUG ".......     : IO APIC version: %04X\n", reg_01.bits.version);
1529 
1530 	/*
1531 	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1532 	 * but the value of reg_02 is read as the previous read register
1533 	 * value, so ignore it if reg_02 == reg_01.
1534 	 */
1535 	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1536 		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1537 		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1538 	}
1539 
1540 	/*
1541 	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1542 	 * or reg_03, but the value of reg_0[23] is read as the previous read
1543 	 * register value, so ignore it if reg_03 == reg_0[12].
1544 	 */
1545 	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1546 	    reg_03.raw != reg_01.raw) {
1547 		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1548 		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1549 	}
1550 
1551 	printk(KERN_DEBUG ".... IRQ redirection table:\n");
1552 
1553 	printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
1554 			  " Stat Dmod Deli Vect:\n");
1555 
1556 	for (i = 0; i <= reg_01.bits.entries; i++) {
1557 		struct IO_APIC_route_entry entry;
1558 
1559 		entry = ioapic_read_entry(apic, i);
1560 
1561 		printk(KERN_DEBUG " %02x %03X ",
1562 			i,
1563 			entry.dest
1564 		);
1565 
1566 		printk("%1d    %1d    %1d   %1d   %1d    %1d    %1d    %02X\n",
1567 			entry.mask,
1568 			entry.trigger,
1569 			entry.irr,
1570 			entry.polarity,
1571 			entry.delivery_status,
1572 			entry.dest_mode,
1573 			entry.delivery_mode,
1574 			entry.vector
1575 		);
1576 	}
1577 	}
1578 	printk(KERN_DEBUG "IRQ to pin mappings:\n");
1579 	for_each_active_irq(irq) {
1580 		struct irq_pin_list *entry;
1581 
1582 		cfg = irq_get_chip_data(irq);
1583 		if (!cfg)
1584 			continue;
1585 		entry = cfg->irq_2_pin;
1586 		if (!entry)
1587 			continue;
1588 		printk(KERN_DEBUG "IRQ%d ", irq);
1589 		for_each_irq_pin(entry, cfg->irq_2_pin)
1590 			printk("-> %d:%d", entry->apic, entry->pin);
1591 		printk("\n");
1592 	}
1593 
1594 	printk(KERN_INFO ".................................... done.\n");
1595 
1596 	return;
1597 }
1598 
1599 __apicdebuginit(void) print_APIC_field(int base)
1600 {
1601 	int i;
1602 
1603 	printk(KERN_DEBUG);
1604 
1605 	for (i = 0; i < 8; i++)
1606 		printk(KERN_CONT "%08x", apic_read(base + i*0x10));
1607 
1608 	printk(KERN_CONT "\n");
1609 }
1610 
1611 __apicdebuginit(void) print_local_APIC(void *dummy)
1612 {
1613 	unsigned int i, v, ver, maxlvt;
1614 	u64 icr;
1615 
1616 	printk(KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
1617 		smp_processor_id(), hard_smp_processor_id());
1618 	v = apic_read(APIC_ID);
1619 	printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, read_apic_id());
1620 	v = apic_read(APIC_LVR);
1621 	printk(KERN_INFO "... APIC VERSION: %08x\n", v);
1622 	ver = GET_APIC_VERSION(v);
1623 	maxlvt = lapic_get_maxlvt();
1624 
1625 	v = apic_read(APIC_TASKPRI);
1626 	printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
1627 
1628 	if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
1629 		if (!APIC_XAPIC(ver)) {
1630 			v = apic_read(APIC_ARBPRI);
1631 			printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
1632 			       v & APIC_ARBPRI_MASK);
1633 		}
1634 		v = apic_read(APIC_PROCPRI);
1635 		printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
1636 	}
1637 
1638 	/*
1639 	 * Remote read supported only in the 82489DX and local APIC for
1640 	 * Pentium processors.
1641 	 */
1642 	if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
1643 		v = apic_read(APIC_RRR);
1644 		printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
1645 	}
1646 
1647 	v = apic_read(APIC_LDR);
1648 	printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
1649 	if (!x2apic_enabled()) {
1650 		v = apic_read(APIC_DFR);
1651 		printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
1652 	}
1653 	v = apic_read(APIC_SPIV);
1654 	printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);
1655 
1656 	printk(KERN_DEBUG "... APIC ISR field:\n");
1657 	print_APIC_field(APIC_ISR);
1658 	printk(KERN_DEBUG "... APIC TMR field:\n");
1659 	print_APIC_field(APIC_TMR);
1660 	printk(KERN_DEBUG "... APIC IRR field:\n");
1661 	print_APIC_field(APIC_IRR);
1662 
1663 	if (APIC_INTEGRATED(ver)) {             /* !82489DX */
1664 		if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
1665 			apic_write(APIC_ESR, 0);
1666 
1667 		v = apic_read(APIC_ESR);
1668 		printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
1669 	}
1670 
1671 	icr = apic_icr_read();
1672 	printk(KERN_DEBUG "... APIC ICR: %08x\n", (u32)icr);
1673 	printk(KERN_DEBUG "... APIC ICR2: %08x\n", (u32)(icr >> 32));
1674 
1675 	v = apic_read(APIC_LVTT);
1676 	printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);
1677 
1678 	if (maxlvt > 3) {                       /* PC is LVT#4. */
1679 		v = apic_read(APIC_LVTPC);
1680 		printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
1681 	}
1682 	v = apic_read(APIC_LVT0);
1683 	printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
1684 	v = apic_read(APIC_LVT1);
1685 	printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);
1686 
1687 	if (maxlvt > 2) {			/* ERR is LVT#3. */
1688 		v = apic_read(APIC_LVTERR);
1689 		printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
1690 	}
1691 
1692 	v = apic_read(APIC_TMICT);
1693 	printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
1694 	v = apic_read(APIC_TMCCT);
1695 	printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
1696 	v = apic_read(APIC_TDCR);
1697 	printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);
1698 
1699 	if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
1700 		v = apic_read(APIC_EFEAT);
1701 		maxlvt = (v >> 16) & 0xff;
1702 		printk(KERN_DEBUG "... APIC EFEAT: %08x\n", v);
1703 		v = apic_read(APIC_ECTRL);
1704 		printk(KERN_DEBUG "... APIC ECTRL: %08x\n", v);
1705 		for (i = 0; i < maxlvt; i++) {
1706 			v = apic_read(APIC_EILVTn(i));
1707 			printk(KERN_DEBUG "... APIC EILVT%d: %08x\n", i, v);
1708 		}
1709 	}
1710 	printk("\n");
1711 }
1712 
1713 __apicdebuginit(void) print_local_APICs(int maxcpu)
1714 {
1715 	int cpu;
1716 
1717 	if (!maxcpu)
1718 		return;
1719 
1720 	preempt_disable();
1721 	for_each_online_cpu(cpu) {
1722 		if (cpu >= maxcpu)
1723 			break;
1724 		smp_call_function_single(cpu, print_local_APIC, NULL, 1);
1725 	}
1726 	preempt_enable();
1727 }
1728 
1729 __apicdebuginit(void) print_PIC(void)
1730 {
1731 	unsigned int v;
1732 	unsigned long flags;
1733 
1734 	if (!legacy_pic->nr_legacy_irqs)
1735 		return;
1736 
1737 	printk(KERN_DEBUG "\nprinting PIC contents\n");
1738 
1739 	raw_spin_lock_irqsave(&i8259A_lock, flags);
1740 
1741 	v = inb(0xa1) << 8 | inb(0x21);
1742 	printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);
1743 
1744 	v = inb(0xa0) << 8 | inb(0x20);
1745 	printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);
1746 
1747 	outb(0x0b,0xa0);
1748 	outb(0x0b,0x20);
1749 	v = inb(0xa0) << 8 | inb(0x20);
1750 	outb(0x0a,0xa0);
1751 	outb(0x0a,0x20);
1752 
1753 	raw_spin_unlock_irqrestore(&i8259A_lock, flags);
1754 
1755 	printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);
1756 
1757 	v = inb(0x4d1) << 8 | inb(0x4d0);
1758 	printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
1759 }
1760 
1761 static int __initdata show_lapic = 1;
1762 static __init int setup_show_lapic(char *arg)
1763 {
1764 	int num = -1;
1765 
1766 	if (strcmp(arg, "all") == 0) {
1767 		show_lapic = CONFIG_NR_CPUS;
1768 	} else {
1769 		get_option(&arg, &num);
1770 		if (num >= 0)
1771 			show_lapic = num;
1772 	}
1773 
1774 	return 1;
1775 }
1776 __setup("show_lapic=", setup_show_lapic);
1777 
1778 __apicdebuginit(int) print_ICs(void)
1779 {
1780 	if (apic_verbosity == APIC_QUIET)
1781 		return 0;
1782 
1783 	print_PIC();
1784 
1785 	/* don't print out if apic is not there */
1786 	if (!cpu_has_apic && !apic_from_smp_config())
1787 		return 0;
1788 
1789 	print_local_APICs(show_lapic);
1790 	print_IO_APIC();
1791 
1792 	return 0;
1793 }
1794 
1795 late_initcall(print_ICs);
1796 
1797 
1798 /* Where if anywhere is the i8259 connect in external int mode */
1799 static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1800 
1801 void __init enable_IO_APIC(void)
1802 {
1803 	int i8259_apic, i8259_pin;
1804 	int apic;
1805 
1806 	if (!legacy_pic->nr_legacy_irqs)
1807 		return;
1808 
1809 	for(apic = 0; apic < nr_ioapics; apic++) {
1810 		int pin;
1811 		/* See if any of the pins is in ExtINT mode */
1812 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
1813 			struct IO_APIC_route_entry entry;
1814 			entry = ioapic_read_entry(apic, pin);
1815 
1816 			/* If the interrupt line is enabled and in ExtInt mode
1817 			 * I have found the pin where the i8259 is connected.
1818 			 */
1819 			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
1820 				ioapic_i8259.apic = apic;
1821 				ioapic_i8259.pin  = pin;
1822 				goto found_i8259;
1823 			}
1824 		}
1825 	}
1826  found_i8259:
1827 	/* Look to see what if the MP table has reported the ExtINT */
1828 	/* If we could not find the appropriate pin by looking at the ioapic
1829 	 * the i8259 probably is not connected the ioapic but give the
1830 	 * mptable a chance anyway.
1831 	 */
1832 	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1833 	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1834 	/* Trust the MP table if nothing is setup in the hardware */
1835 	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1836 		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
1837 		ioapic_i8259.pin  = i8259_pin;
1838 		ioapic_i8259.apic = i8259_apic;
1839 	}
1840 	/* Complain if the MP table and the hardware disagree */
1841 	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1842 		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1843 	{
1844 		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
1845 	}
1846 
1847 	/*
1848 	 * Do not trust the IO-APIC being empty at bootup
1849 	 */
1850 	clear_IO_APIC();
1851 }
1852 
1853 /*
1854  * Not an __init, needed by the reboot code
1855  */
1856 void disable_IO_APIC(void)
1857 {
1858 	/*
1859 	 * Clear the IO-APIC before rebooting:
1860 	 */
1861 	clear_IO_APIC();
1862 
1863 	if (!legacy_pic->nr_legacy_irqs)
1864 		return;
1865 
1866 	/*
1867 	 * If the i8259 is routed through an IOAPIC
1868 	 * Put that IOAPIC in virtual wire mode
1869 	 * so legacy interrupts can be delivered.
1870 	 *
1871 	 * With interrupt-remapping, for now we will use virtual wire A mode,
1872 	 * as virtual wire B is little complex (need to configure both
1873 	 * IOAPIC RTE as well as interrupt-remapping table entry).
1874 	 * As this gets called during crash dump, keep this simple for now.
1875 	 */
1876 	if (ioapic_i8259.pin != -1 && !intr_remapping_enabled) {
1877 		struct IO_APIC_route_entry entry;
1878 
1879 		memset(&entry, 0, sizeof(entry));
1880 		entry.mask            = 0; /* Enabled */
1881 		entry.trigger         = 0; /* Edge */
1882 		entry.irr             = 0;
1883 		entry.polarity        = 0; /* High */
1884 		entry.delivery_status = 0;
1885 		entry.dest_mode       = 0; /* Physical */
1886 		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
1887 		entry.vector          = 0;
1888 		entry.dest            = read_apic_id();
1889 
1890 		/*
1891 		 * Add it to the IO-APIC irq-routing table:
1892 		 */
1893 		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1894 	}
1895 
1896 	/*
1897 	 * Use virtual wire A mode when interrupt remapping is enabled.
1898 	 */
1899 	if (cpu_has_apic || apic_from_smp_config())
1900 		disconnect_bsp_APIC(!intr_remapping_enabled &&
1901 				ioapic_i8259.pin != -1);
1902 }
1903 
1904 #ifdef CONFIG_X86_32
1905 /*
1906  * function to set the IO-APIC physical IDs based on the
1907  * values stored in the MPC table.
1908  *
1909  * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1910  */
1911 void __init setup_ioapic_ids_from_mpc_nocheck(void)
1912 {
1913 	union IO_APIC_reg_00 reg_00;
1914 	physid_mask_t phys_id_present_map;
1915 	int apic_id;
1916 	int i;
1917 	unsigned char old_id;
1918 	unsigned long flags;
1919 
1920 	/*
1921 	 * This is broken; anything with a real cpu count has to
1922 	 * circumvent this idiocy regardless.
1923 	 */
1924 	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
1925 
1926 	/*
1927 	 * Set the IOAPIC ID to the value stored in the MPC table.
1928 	 */
1929 	for (apic_id = 0; apic_id < nr_ioapics; apic_id++) {
1930 
1931 		/* Read the register 0 value */
1932 		raw_spin_lock_irqsave(&ioapic_lock, flags);
1933 		reg_00.raw = io_apic_read(apic_id, 0);
1934 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1935 
1936 		old_id = mpc_ioapic_id(apic_id);
1937 
1938 		if (mpc_ioapic_id(apic_id) >= get_physical_broadcast()) {
1939 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1940 				apic_id, mpc_ioapic_id(apic_id));
1941 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1942 				reg_00.bits.ID);
1943 			ioapics[apic_id].mp_config.apicid = reg_00.bits.ID;
1944 		}
1945 
1946 		/*
1947 		 * Sanity check, is the ID really free? Every APIC in a
1948 		 * system must have a unique ID or we get lots of nice
1949 		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1950 		 */
1951 		if (apic->check_apicid_used(&phys_id_present_map,
1952 					    mpc_ioapic_id(apic_id))) {
1953 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1954 				apic_id, mpc_ioapic_id(apic_id));
1955 			for (i = 0; i < get_physical_broadcast(); i++)
1956 				if (!physid_isset(i, phys_id_present_map))
1957 					break;
1958 			if (i >= get_physical_broadcast())
1959 				panic("Max APIC ID exceeded!\n");
1960 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1961 				i);
1962 			physid_set(i, phys_id_present_map);
1963 			ioapics[apic_id].mp_config.apicid = i;
1964 		} else {
1965 			physid_mask_t tmp;
1966 			apic->apicid_to_cpu_present(mpc_ioapic_id(apic_id),
1967 						    &tmp);
1968 			apic_printk(APIC_VERBOSE, "Setting %d in the "
1969 					"phys_id_present_map\n",
1970 					mpc_ioapic_id(apic_id));
1971 			physids_or(phys_id_present_map, phys_id_present_map, tmp);
1972 		}
1973 
1974 		/*
1975 		 * We need to adjust the IRQ routing table
1976 		 * if the ID changed.
1977 		 */
1978 		if (old_id != mpc_ioapic_id(apic_id))
1979 			for (i = 0; i < mp_irq_entries; i++)
1980 				if (mp_irqs[i].dstapic == old_id)
1981 					mp_irqs[i].dstapic
1982 						= mpc_ioapic_id(apic_id);
1983 
1984 		/*
1985 		 * Update the ID register according to the right value
1986 		 * from the MPC table if they are different.
1987 		 */
1988 		if (mpc_ioapic_id(apic_id) == reg_00.bits.ID)
1989 			continue;
1990 
1991 		apic_printk(APIC_VERBOSE, KERN_INFO
1992 			"...changing IO-APIC physical APIC ID to %d ...",
1993 			mpc_ioapic_id(apic_id));
1994 
1995 		reg_00.bits.ID = mpc_ioapic_id(apic_id);
1996 		raw_spin_lock_irqsave(&ioapic_lock, flags);
1997 		io_apic_write(apic_id, 0, reg_00.raw);
1998 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1999 
2000 		/*
2001 		 * Sanity check
2002 		 */
2003 		raw_spin_lock_irqsave(&ioapic_lock, flags);
2004 		reg_00.raw = io_apic_read(apic_id, 0);
2005 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2006 		if (reg_00.bits.ID != mpc_ioapic_id(apic_id))
2007 			printk("could not set ID!\n");
2008 		else
2009 			apic_printk(APIC_VERBOSE, " ok.\n");
2010 	}
2011 }
2012 
2013 void __init setup_ioapic_ids_from_mpc(void)
2014 {
2015 
2016 	if (acpi_ioapic)
2017 		return;
2018 	/*
2019 	 * Don't check I/O APIC IDs for xAPIC systems.  They have
2020 	 * no meaning without the serial APIC bus.
2021 	 */
2022 	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
2023 		|| APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
2024 		return;
2025 	setup_ioapic_ids_from_mpc_nocheck();
2026 }
2027 #endif
2028 
2029 int no_timer_check __initdata;
2030 
2031 static int __init notimercheck(char *s)
2032 {
2033 	no_timer_check = 1;
2034 	return 1;
2035 }
2036 __setup("no_timer_check", notimercheck);
2037 
2038 /*
2039  * There is a nasty bug in some older SMP boards, their mptable lies
2040  * about the timer IRQ. We do the following to work around the situation:
2041  *
2042  *	- timer IRQ defaults to IO-APIC IRQ
2043  *	- if this function detects that timer IRQs are defunct, then we fall
2044  *	  back to ISA timer IRQs
2045  */
2046 static int __init timer_irq_works(void)
2047 {
2048 	unsigned long t1 = jiffies;
2049 	unsigned long flags;
2050 
2051 	if (no_timer_check)
2052 		return 1;
2053 
2054 	local_save_flags(flags);
2055 	local_irq_enable();
2056 	/* Let ten ticks pass... */
2057 	mdelay((10 * 1000) / HZ);
2058 	local_irq_restore(flags);
2059 
2060 	/*
2061 	 * Expect a few ticks at least, to be sure some possible
2062 	 * glue logic does not lock up after one or two first
2063 	 * ticks in a non-ExtINT mode.  Also the local APIC
2064 	 * might have cached one ExtINT interrupt.  Finally, at
2065 	 * least one tick may be lost due to delays.
2066 	 */
2067 
2068 	/* jiffies wrap? */
2069 	if (time_after(jiffies, t1 + 4))
2070 		return 1;
2071 	return 0;
2072 }
2073 
2074 /*
2075  * In the SMP+IOAPIC case it might happen that there are an unspecified
2076  * number of pending IRQ events unhandled. These cases are very rare,
2077  * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
2078  * better to do it this way as thus we do not have to be aware of
2079  * 'pending' interrupts in the IRQ path, except at this point.
2080  */
2081 /*
2082  * Edge triggered needs to resend any interrupt
2083  * that was delayed but this is now handled in the device
2084  * independent code.
2085  */
2086 
2087 /*
2088  * Starting up a edge-triggered IO-APIC interrupt is
2089  * nasty - we need to make sure that we get the edge.
2090  * If it is already asserted for some reason, we need
2091  * return 1 to indicate that is was pending.
2092  *
2093  * This is not complete - we should be able to fake
2094  * an edge even if it isn't on the 8259A...
2095  */
2096 
2097 static unsigned int startup_ioapic_irq(struct irq_data *data)
2098 {
2099 	int was_pending = 0, irq = data->irq;
2100 	unsigned long flags;
2101 
2102 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2103 	if (irq < legacy_pic->nr_legacy_irqs) {
2104 		legacy_pic->mask(irq);
2105 		if (legacy_pic->irq_pending(irq))
2106 			was_pending = 1;
2107 	}
2108 	__unmask_ioapic(data->chip_data);
2109 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2110 
2111 	return was_pending;
2112 }
2113 
2114 static int ioapic_retrigger_irq(struct irq_data *data)
2115 {
2116 	struct irq_cfg *cfg = data->chip_data;
2117 	unsigned long flags;
2118 
2119 	raw_spin_lock_irqsave(&vector_lock, flags);
2120 	apic->send_IPI_mask(cpumask_of(cpumask_first(cfg->domain)), cfg->vector);
2121 	raw_spin_unlock_irqrestore(&vector_lock, flags);
2122 
2123 	return 1;
2124 }
2125 
2126 /*
2127  * Level and edge triggered IO-APIC interrupts need different handling,
2128  * so we use two separate IRQ descriptors. Edge triggered IRQs can be
2129  * handled with the level-triggered descriptor, but that one has slightly
2130  * more overhead. Level-triggered interrupts cannot be handled with the
2131  * edge-triggered handler, without risking IRQ storms and other ugly
2132  * races.
2133  */
2134 
2135 #ifdef CONFIG_SMP
2136 void send_cleanup_vector(struct irq_cfg *cfg)
2137 {
2138 	cpumask_var_t cleanup_mask;
2139 
2140 	if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
2141 		unsigned int i;
2142 		for_each_cpu_and(i, cfg->old_domain, cpu_online_mask)
2143 			apic->send_IPI_mask(cpumask_of(i), IRQ_MOVE_CLEANUP_VECTOR);
2144 	} else {
2145 		cpumask_and(cleanup_mask, cfg->old_domain, cpu_online_mask);
2146 		apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
2147 		free_cpumask_var(cleanup_mask);
2148 	}
2149 	cfg->move_in_progress = 0;
2150 }
2151 
2152 static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq_cfg *cfg)
2153 {
2154 	int apic, pin;
2155 	struct irq_pin_list *entry;
2156 	u8 vector = cfg->vector;
2157 
2158 	for_each_irq_pin(entry, cfg->irq_2_pin) {
2159 		unsigned int reg;
2160 
2161 		apic = entry->apic;
2162 		pin = entry->pin;
2163 		/*
2164 		 * With interrupt-remapping, destination information comes
2165 		 * from interrupt-remapping table entry.
2166 		 */
2167 		if (!irq_remapped(cfg))
2168 			io_apic_write(apic, 0x11 + pin*2, dest);
2169 		reg = io_apic_read(apic, 0x10 + pin*2);
2170 		reg &= ~IO_APIC_REDIR_VECTOR_MASK;
2171 		reg |= vector;
2172 		io_apic_modify(apic, 0x10 + pin*2, reg);
2173 	}
2174 }
2175 
2176 /*
2177  * Either sets data->affinity to a valid value, and returns
2178  * ->cpu_mask_to_apicid of that in dest_id, or returns -1 and
2179  * leaves data->affinity untouched.
2180  */
2181 int __ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2182 			  unsigned int *dest_id)
2183 {
2184 	struct irq_cfg *cfg = data->chip_data;
2185 
2186 	if (!cpumask_intersects(mask, cpu_online_mask))
2187 		return -1;
2188 
2189 	if (assign_irq_vector(data->irq, data->chip_data, mask))
2190 		return -1;
2191 
2192 	cpumask_copy(data->affinity, mask);
2193 
2194 	*dest_id = apic->cpu_mask_to_apicid_and(mask, cfg->domain);
2195 	return 0;
2196 }
2197 
2198 static int
2199 ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2200 		    bool force)
2201 {
2202 	unsigned int dest, irq = data->irq;
2203 	unsigned long flags;
2204 	int ret;
2205 
2206 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2207 	ret = __ioapic_set_affinity(data, mask, &dest);
2208 	if (!ret) {
2209 		/* Only the high 8 bits are valid. */
2210 		dest = SET_APIC_LOGICAL_ID(dest);
2211 		__target_IO_APIC_irq(irq, dest, data->chip_data);
2212 	}
2213 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2214 	return ret;
2215 }
2216 
2217 #ifdef CONFIG_INTR_REMAP
2218 
2219 /*
2220  * Migrate the IO-APIC irq in the presence of intr-remapping.
2221  *
2222  * For both level and edge triggered, irq migration is a simple atomic
2223  * update(of vector and cpu destination) of IRTE and flush the hardware cache.
2224  *
2225  * For level triggered, we eliminate the io-apic RTE modification (with the
2226  * updated vector information), by using a virtual vector (io-apic pin number).
2227  * Real vector that is used for interrupting cpu will be coming from
2228  * the interrupt-remapping table entry.
2229  */
2230 static int
2231 ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2232 		       bool force)
2233 {
2234 	struct irq_cfg *cfg = data->chip_data;
2235 	unsigned int dest, irq = data->irq;
2236 	struct irte irte;
2237 
2238 	if (!cpumask_intersects(mask, cpu_online_mask))
2239 		return -EINVAL;
2240 
2241 	if (get_irte(irq, &irte))
2242 		return -EBUSY;
2243 
2244 	if (assign_irq_vector(irq, cfg, mask))
2245 		return -EBUSY;
2246 
2247 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, mask);
2248 
2249 	irte.vector = cfg->vector;
2250 	irte.dest_id = IRTE_DEST(dest);
2251 
2252 	/*
2253 	 * Modified the IRTE and flushes the Interrupt entry cache.
2254 	 */
2255 	modify_irte(irq, &irte);
2256 
2257 	if (cfg->move_in_progress)
2258 		send_cleanup_vector(cfg);
2259 
2260 	cpumask_copy(data->affinity, mask);
2261 	return 0;
2262 }
2263 
2264 #else
2265 static inline int
2266 ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2267 		       bool force)
2268 {
2269 	return 0;
2270 }
2271 #endif
2272 
2273 asmlinkage void smp_irq_move_cleanup_interrupt(void)
2274 {
2275 	unsigned vector, me;
2276 
2277 	ack_APIC_irq();
2278 	exit_idle();
2279 	irq_enter();
2280 
2281 	me = smp_processor_id();
2282 	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
2283 		unsigned int irq;
2284 		unsigned int irr;
2285 		struct irq_desc *desc;
2286 		struct irq_cfg *cfg;
2287 		irq = __this_cpu_read(vector_irq[vector]);
2288 
2289 		if (irq == -1)
2290 			continue;
2291 
2292 		desc = irq_to_desc(irq);
2293 		if (!desc)
2294 			continue;
2295 
2296 		cfg = irq_cfg(irq);
2297 		raw_spin_lock(&desc->lock);
2298 
2299 		/*
2300 		 * Check if the irq migration is in progress. If so, we
2301 		 * haven't received the cleanup request yet for this irq.
2302 		 */
2303 		if (cfg->move_in_progress)
2304 			goto unlock;
2305 
2306 		if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain))
2307 			goto unlock;
2308 
2309 		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
2310 		/*
2311 		 * Check if the vector that needs to be cleanedup is
2312 		 * registered at the cpu's IRR. If so, then this is not
2313 		 * the best time to clean it up. Lets clean it up in the
2314 		 * next attempt by sending another IRQ_MOVE_CLEANUP_VECTOR
2315 		 * to myself.
2316 		 */
2317 		if (irr  & (1 << (vector % 32))) {
2318 			apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
2319 			goto unlock;
2320 		}
2321 		__this_cpu_write(vector_irq[vector], -1);
2322 unlock:
2323 		raw_spin_unlock(&desc->lock);
2324 	}
2325 
2326 	irq_exit();
2327 }
2328 
2329 static void __irq_complete_move(struct irq_cfg *cfg, unsigned vector)
2330 {
2331 	unsigned me;
2332 
2333 	if (likely(!cfg->move_in_progress))
2334 		return;
2335 
2336 	me = smp_processor_id();
2337 
2338 	if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain))
2339 		send_cleanup_vector(cfg);
2340 }
2341 
2342 static void irq_complete_move(struct irq_cfg *cfg)
2343 {
2344 	__irq_complete_move(cfg, ~get_irq_regs()->orig_ax);
2345 }
2346 
2347 void irq_force_complete_move(int irq)
2348 {
2349 	struct irq_cfg *cfg = irq_get_chip_data(irq);
2350 
2351 	if (!cfg)
2352 		return;
2353 
2354 	__irq_complete_move(cfg, cfg->vector);
2355 }
2356 #else
2357 static inline void irq_complete_move(struct irq_cfg *cfg) { }
2358 #endif
2359 
2360 static void ack_apic_edge(struct irq_data *data)
2361 {
2362 	irq_complete_move(data->chip_data);
2363 	irq_move_irq(data);
2364 	ack_APIC_irq();
2365 }
2366 
2367 atomic_t irq_mis_count;
2368 
2369 /*
2370  * IO-APIC versions below 0x20 don't support EOI register.
2371  * For the record, here is the information about various versions:
2372  *     0Xh     82489DX
2373  *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
2374  *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
2375  *     30h-FFh Reserved
2376  *
2377  * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
2378  * version as 0x2. This is an error with documentation and these ICH chips
2379  * use io-apic's of version 0x20.
2380  *
2381  * For IO-APIC's with EOI register, we use that to do an explicit EOI.
2382  * Otherwise, we simulate the EOI message manually by changing the trigger
2383  * mode to edge and then back to level, with RTE being masked during this.
2384 */
2385 static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
2386 {
2387 	struct irq_pin_list *entry;
2388 	unsigned long flags;
2389 
2390 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2391 	for_each_irq_pin(entry, cfg->irq_2_pin) {
2392 		if (mpc_ioapic_ver(entry->apic) >= 0x20) {
2393 			/*
2394 			 * Intr-remapping uses pin number as the virtual vector
2395 			 * in the RTE. Actual vector is programmed in
2396 			 * intr-remapping table entry. Hence for the io-apic
2397 			 * EOI we use the pin number.
2398 			 */
2399 			if (irq_remapped(cfg))
2400 				io_apic_eoi(entry->apic, entry->pin);
2401 			else
2402 				io_apic_eoi(entry->apic, cfg->vector);
2403 		} else {
2404 			__mask_and_edge_IO_APIC_irq(entry);
2405 			__unmask_and_level_IO_APIC_irq(entry);
2406 		}
2407 	}
2408 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2409 }
2410 
2411 static void ack_apic_level(struct irq_data *data)
2412 {
2413 	struct irq_cfg *cfg = data->chip_data;
2414 	int i, do_unmask_irq = 0, irq = data->irq;
2415 	unsigned long v;
2416 
2417 	irq_complete_move(cfg);
2418 #ifdef CONFIG_GENERIC_PENDING_IRQ
2419 	/* If we are moving the irq we need to mask it */
2420 	if (unlikely(irqd_is_setaffinity_pending(data))) {
2421 		do_unmask_irq = 1;
2422 		mask_ioapic(cfg);
2423 	}
2424 #endif
2425 
2426 	/*
2427 	 * It appears there is an erratum which affects at least version 0x11
2428 	 * of I/O APIC (that's the 82093AA and cores integrated into various
2429 	 * chipsets).  Under certain conditions a level-triggered interrupt is
2430 	 * erroneously delivered as edge-triggered one but the respective IRR
2431 	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
2432 	 * message but it will never arrive and further interrupts are blocked
2433 	 * from the source.  The exact reason is so far unknown, but the
2434 	 * phenomenon was observed when two consecutive interrupt requests
2435 	 * from a given source get delivered to the same CPU and the source is
2436 	 * temporarily disabled in between.
2437 	 *
2438 	 * A workaround is to simulate an EOI message manually.  We achieve it
2439 	 * by setting the trigger mode to edge and then to level when the edge
2440 	 * trigger mode gets detected in the TMR of a local APIC for a
2441 	 * level-triggered interrupt.  We mask the source for the time of the
2442 	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
2443 	 * The idea is from Manfred Spraul.  --macro
2444 	 *
2445 	 * Also in the case when cpu goes offline, fixup_irqs() will forward
2446 	 * any unhandled interrupt on the offlined cpu to the new cpu
2447 	 * destination that is handling the corresponding interrupt. This
2448 	 * interrupt forwarding is done via IPI's. Hence, in this case also
2449 	 * level-triggered io-apic interrupt will be seen as an edge
2450 	 * interrupt in the IRR. And we can't rely on the cpu's EOI
2451 	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
2452 	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
2453 	 * supporting EOI register, we do an explicit EOI to clear the
2454 	 * remote IRR and on IO-APIC's which don't have an EOI register,
2455 	 * we use the above logic (mask+edge followed by unmask+level) from
2456 	 * Manfred Spraul to clear the remote IRR.
2457 	 */
2458 	i = cfg->vector;
2459 	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
2460 
2461 	/*
2462 	 * We must acknowledge the irq before we move it or the acknowledge will
2463 	 * not propagate properly.
2464 	 */
2465 	ack_APIC_irq();
2466 
2467 	/*
2468 	 * Tail end of clearing remote IRR bit (either by delivering the EOI
2469 	 * message via io-apic EOI register write or simulating it using
2470 	 * mask+edge followed by unnask+level logic) manually when the
2471 	 * level triggered interrupt is seen as the edge triggered interrupt
2472 	 * at the cpu.
2473 	 */
2474 	if (!(v & (1 << (i & 0x1f)))) {
2475 		atomic_inc(&irq_mis_count);
2476 
2477 		eoi_ioapic_irq(irq, cfg);
2478 	}
2479 
2480 	/* Now we can move and renable the irq */
2481 	if (unlikely(do_unmask_irq)) {
2482 		/* Only migrate the irq if the ack has been received.
2483 		 *
2484 		 * On rare occasions the broadcast level triggered ack gets
2485 		 * delayed going to ioapics, and if we reprogram the
2486 		 * vector while Remote IRR is still set the irq will never
2487 		 * fire again.
2488 		 *
2489 		 * To prevent this scenario we read the Remote IRR bit
2490 		 * of the ioapic.  This has two effects.
2491 		 * - On any sane system the read of the ioapic will
2492 		 *   flush writes (and acks) going to the ioapic from
2493 		 *   this cpu.
2494 		 * - We get to see if the ACK has actually been delivered.
2495 		 *
2496 		 * Based on failed experiments of reprogramming the
2497 		 * ioapic entry from outside of irq context starting
2498 		 * with masking the ioapic entry and then polling until
2499 		 * Remote IRR was clear before reprogramming the
2500 		 * ioapic I don't trust the Remote IRR bit to be
2501 		 * completey accurate.
2502 		 *
2503 		 * However there appears to be no other way to plug
2504 		 * this race, so if the Remote IRR bit is not
2505 		 * accurate and is causing problems then it is a hardware bug
2506 		 * and you can go talk to the chipset vendor about it.
2507 		 */
2508 		if (!io_apic_level_ack_pending(cfg))
2509 			irq_move_masked_irq(data);
2510 		unmask_ioapic(cfg);
2511 	}
2512 }
2513 
2514 #ifdef CONFIG_INTR_REMAP
2515 static void ir_ack_apic_edge(struct irq_data *data)
2516 {
2517 	ack_APIC_irq();
2518 }
2519 
2520 static void ir_ack_apic_level(struct irq_data *data)
2521 {
2522 	ack_APIC_irq();
2523 	eoi_ioapic_irq(data->irq, data->chip_data);
2524 }
2525 #endif /* CONFIG_INTR_REMAP */
2526 
2527 static struct irq_chip ioapic_chip __read_mostly = {
2528 	.name			= "IO-APIC",
2529 	.irq_startup		= startup_ioapic_irq,
2530 	.irq_mask		= mask_ioapic_irq,
2531 	.irq_unmask		= unmask_ioapic_irq,
2532 	.irq_ack		= ack_apic_edge,
2533 	.irq_eoi		= ack_apic_level,
2534 #ifdef CONFIG_SMP
2535 	.irq_set_affinity	= ioapic_set_affinity,
2536 #endif
2537 	.irq_retrigger		= ioapic_retrigger_irq,
2538 };
2539 
2540 static struct irq_chip ir_ioapic_chip __read_mostly = {
2541 	.name			= "IR-IO-APIC",
2542 	.irq_startup		= startup_ioapic_irq,
2543 	.irq_mask		= mask_ioapic_irq,
2544 	.irq_unmask		= unmask_ioapic_irq,
2545 #ifdef CONFIG_INTR_REMAP
2546 	.irq_ack		= ir_ack_apic_edge,
2547 	.irq_eoi		= ir_ack_apic_level,
2548 #ifdef CONFIG_SMP
2549 	.irq_set_affinity	= ir_ioapic_set_affinity,
2550 #endif
2551 #endif
2552 	.irq_retrigger		= ioapic_retrigger_irq,
2553 };
2554 
2555 static inline void init_IO_APIC_traps(void)
2556 {
2557 	struct irq_cfg *cfg;
2558 	unsigned int irq;
2559 
2560 	/*
2561 	 * NOTE! The local APIC isn't very good at handling
2562 	 * multiple interrupts at the same interrupt level.
2563 	 * As the interrupt level is determined by taking the
2564 	 * vector number and shifting that right by 4, we
2565 	 * want to spread these out a bit so that they don't
2566 	 * all fall in the same interrupt level.
2567 	 *
2568 	 * Also, we've got to be careful not to trash gate
2569 	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
2570 	 */
2571 	for_each_active_irq(irq) {
2572 		cfg = irq_get_chip_data(irq);
2573 		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
2574 			/*
2575 			 * Hmm.. We don't have an entry for this,
2576 			 * so default to an old-fashioned 8259
2577 			 * interrupt if we can..
2578 			 */
2579 			if (irq < legacy_pic->nr_legacy_irqs)
2580 				legacy_pic->make_irq(irq);
2581 			else
2582 				/* Strange. Oh, well.. */
2583 				irq_set_chip(irq, &no_irq_chip);
2584 		}
2585 	}
2586 }
2587 
2588 /*
2589  * The local APIC irq-chip implementation:
2590  */
2591 
2592 static void mask_lapic_irq(struct irq_data *data)
2593 {
2594 	unsigned long v;
2595 
2596 	v = apic_read(APIC_LVT0);
2597 	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
2598 }
2599 
2600 static void unmask_lapic_irq(struct irq_data *data)
2601 {
2602 	unsigned long v;
2603 
2604 	v = apic_read(APIC_LVT0);
2605 	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
2606 }
2607 
2608 static void ack_lapic_irq(struct irq_data *data)
2609 {
2610 	ack_APIC_irq();
2611 }
2612 
2613 static struct irq_chip lapic_chip __read_mostly = {
2614 	.name		= "local-APIC",
2615 	.irq_mask	= mask_lapic_irq,
2616 	.irq_unmask	= unmask_lapic_irq,
2617 	.irq_ack	= ack_lapic_irq,
2618 };
2619 
2620 static void lapic_register_intr(int irq)
2621 {
2622 	irq_clear_status_flags(irq, IRQ_LEVEL);
2623 	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
2624 				      "edge");
2625 }
2626 
2627 /*
2628  * This looks a bit hackish but it's about the only one way of sending
2629  * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2630  * not support the ExtINT mode, unfortunately.  We need to send these
2631  * cycles as some i82489DX-based boards have glue logic that keeps the
2632  * 8259A interrupt line asserted until INTA.  --macro
2633  */
2634 static inline void __init unlock_ExtINT_logic(void)
2635 {
2636 	int apic, pin, i;
2637 	struct IO_APIC_route_entry entry0, entry1;
2638 	unsigned char save_control, save_freq_select;
2639 
2640 	pin  = find_isa_irq_pin(8, mp_INT);
2641 	if (pin == -1) {
2642 		WARN_ON_ONCE(1);
2643 		return;
2644 	}
2645 	apic = find_isa_irq_apic(8, mp_INT);
2646 	if (apic == -1) {
2647 		WARN_ON_ONCE(1);
2648 		return;
2649 	}
2650 
2651 	entry0 = ioapic_read_entry(apic, pin);
2652 	clear_IO_APIC_pin(apic, pin);
2653 
2654 	memset(&entry1, 0, sizeof(entry1));
2655 
2656 	entry1.dest_mode = 0;			/* physical delivery */
2657 	entry1.mask = 0;			/* unmask IRQ now */
2658 	entry1.dest = hard_smp_processor_id();
2659 	entry1.delivery_mode = dest_ExtINT;
2660 	entry1.polarity = entry0.polarity;
2661 	entry1.trigger = 0;
2662 	entry1.vector = 0;
2663 
2664 	ioapic_write_entry(apic, pin, entry1);
2665 
2666 	save_control = CMOS_READ(RTC_CONTROL);
2667 	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2668 	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2669 		   RTC_FREQ_SELECT);
2670 	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2671 
2672 	i = 100;
2673 	while (i-- > 0) {
2674 		mdelay(10);
2675 		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2676 			i -= 10;
2677 	}
2678 
2679 	CMOS_WRITE(save_control, RTC_CONTROL);
2680 	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2681 	clear_IO_APIC_pin(apic, pin);
2682 
2683 	ioapic_write_entry(apic, pin, entry0);
2684 }
2685 
2686 static int disable_timer_pin_1 __initdata;
2687 /* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2688 static int __init disable_timer_pin_setup(char *arg)
2689 {
2690 	disable_timer_pin_1 = 1;
2691 	return 0;
2692 }
2693 early_param("disable_timer_pin_1", disable_timer_pin_setup);
2694 
2695 int timer_through_8259 __initdata;
2696 
2697 /*
2698  * This code may look a bit paranoid, but it's supposed to cooperate with
2699  * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2700  * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2701  * fanatically on his truly buggy board.
2702  *
2703  * FIXME: really need to revamp this for all platforms.
2704  */
2705 static inline void __init check_timer(void)
2706 {
2707 	struct irq_cfg *cfg = irq_get_chip_data(0);
2708 	int node = cpu_to_node(0);
2709 	int apic1, pin1, apic2, pin2;
2710 	unsigned long flags;
2711 	int no_pin1 = 0;
2712 
2713 	local_irq_save(flags);
2714 
2715 	/*
2716 	 * get/set the timer IRQ vector:
2717 	 */
2718 	legacy_pic->mask(0);
2719 	assign_irq_vector(0, cfg, apic->target_cpus());
2720 
2721 	/*
2722 	 * As IRQ0 is to be enabled in the 8259A, the virtual
2723 	 * wire has to be disabled in the local APIC.  Also
2724 	 * timer interrupts need to be acknowledged manually in
2725 	 * the 8259A for the i82489DX when using the NMI
2726 	 * watchdog as that APIC treats NMIs as level-triggered.
2727 	 * The AEOI mode will finish them in the 8259A
2728 	 * automatically.
2729 	 */
2730 	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2731 	legacy_pic->init(1);
2732 
2733 	pin1  = find_isa_irq_pin(0, mp_INT);
2734 	apic1 = find_isa_irq_apic(0, mp_INT);
2735 	pin2  = ioapic_i8259.pin;
2736 	apic2 = ioapic_i8259.apic;
2737 
2738 	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
2739 		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
2740 		    cfg->vector, apic1, pin1, apic2, pin2);
2741 
2742 	/*
2743 	 * Some BIOS writers are clueless and report the ExtINTA
2744 	 * I/O APIC input from the cascaded 8259A as the timer
2745 	 * interrupt input.  So just in case, if only one pin
2746 	 * was found above, try it both directly and through the
2747 	 * 8259A.
2748 	 */
2749 	if (pin1 == -1) {
2750 		if (intr_remapping_enabled)
2751 			panic("BIOS bug: timer not connected to IO-APIC");
2752 		pin1 = pin2;
2753 		apic1 = apic2;
2754 		no_pin1 = 1;
2755 	} else if (pin2 == -1) {
2756 		pin2 = pin1;
2757 		apic2 = apic1;
2758 	}
2759 
2760 	if (pin1 != -1) {
2761 		/*
2762 		 * Ok, does IRQ0 through the IOAPIC work?
2763 		 */
2764 		if (no_pin1) {
2765 			add_pin_to_irq_node(cfg, node, apic1, pin1);
2766 			setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
2767 		} else {
2768 			/* for edge trigger, setup_ioapic_irq already
2769 			 * leave it unmasked.
2770 			 * so only need to unmask if it is level-trigger
2771 			 * do we really have level trigger timer?
2772 			 */
2773 			int idx;
2774 			idx = find_irq_entry(apic1, pin1, mp_INT);
2775 			if (idx != -1 && irq_trigger(idx))
2776 				unmask_ioapic(cfg);
2777 		}
2778 		if (timer_irq_works()) {
2779 			if (disable_timer_pin_1 > 0)
2780 				clear_IO_APIC_pin(0, pin1);
2781 			goto out;
2782 		}
2783 		if (intr_remapping_enabled)
2784 			panic("timer doesn't work through Interrupt-remapped IO-APIC");
2785 		local_irq_disable();
2786 		clear_IO_APIC_pin(apic1, pin1);
2787 		if (!no_pin1)
2788 			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
2789 				    "8254 timer not connected to IO-APIC\n");
2790 
2791 		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
2792 			    "(IRQ0) through the 8259A ...\n");
2793 		apic_printk(APIC_QUIET, KERN_INFO
2794 			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
2795 		/*
2796 		 * legacy devices should be connected to IO APIC #0
2797 		 */
2798 		replace_pin_at_irq_node(cfg, node, apic1, pin1, apic2, pin2);
2799 		setup_timer_IRQ0_pin(apic2, pin2, cfg->vector);
2800 		legacy_pic->unmask(0);
2801 		if (timer_irq_works()) {
2802 			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
2803 			timer_through_8259 = 1;
2804 			goto out;
2805 		}
2806 		/*
2807 		 * Cleanup, just in case ...
2808 		 */
2809 		local_irq_disable();
2810 		legacy_pic->mask(0);
2811 		clear_IO_APIC_pin(apic2, pin2);
2812 		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
2813 	}
2814 
2815 	apic_printk(APIC_QUIET, KERN_INFO
2816 		    "...trying to set up timer as Virtual Wire IRQ...\n");
2817 
2818 	lapic_register_intr(0);
2819 	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2820 	legacy_pic->unmask(0);
2821 
2822 	if (timer_irq_works()) {
2823 		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2824 		goto out;
2825 	}
2826 	local_irq_disable();
2827 	legacy_pic->mask(0);
2828 	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2829 	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
2830 
2831 	apic_printk(APIC_QUIET, KERN_INFO
2832 		    "...trying to set up timer as ExtINT IRQ...\n");
2833 
2834 	legacy_pic->init(0);
2835 	legacy_pic->make_irq(0);
2836 	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2837 
2838 	unlock_ExtINT_logic();
2839 
2840 	if (timer_irq_works()) {
2841 		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2842 		goto out;
2843 	}
2844 	local_irq_disable();
2845 	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
2846 	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2847 		"report.  Then try booting with the 'noapic' option.\n");
2848 out:
2849 	local_irq_restore(flags);
2850 }
2851 
2852 /*
2853  * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2854  * to devices.  However there may be an I/O APIC pin available for
2855  * this interrupt regardless.  The pin may be left unconnected, but
2856  * typically it will be reused as an ExtINT cascade interrupt for
2857  * the master 8259A.  In the MPS case such a pin will normally be
2858  * reported as an ExtINT interrupt in the MP table.  With ACPI
2859  * there is no provision for ExtINT interrupts, and in the absence
2860  * of an override it would be treated as an ordinary ISA I/O APIC
2861  * interrupt, that is edge-triggered and unmasked by default.  We
2862  * used to do this, but it caused problems on some systems because
2863  * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2864  * the same ExtINT cascade interrupt to drive the local APIC of the
2865  * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2866  * the I/O APIC in all cases now.  No actual device should request
2867  * it anyway.  --macro
2868  */
2869 #define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2870 
2871 void __init setup_IO_APIC(void)
2872 {
2873 
2874 	/*
2875 	 * calling enable_IO_APIC() is moved to setup_local_APIC for BP
2876 	 */
2877 	io_apic_irqs = legacy_pic->nr_legacy_irqs ? ~PIC_IRQS : ~0UL;
2878 
2879 	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
2880 	/*
2881          * Set up IO-APIC IRQ routing.
2882          */
2883 	x86_init.mpparse.setup_ioapic_ids();
2884 
2885 	sync_Arb_IDs();
2886 	setup_IO_APIC_irqs();
2887 	init_IO_APIC_traps();
2888 	if (legacy_pic->nr_legacy_irqs)
2889 		check_timer();
2890 }
2891 
2892 /*
2893  *      Called after all the initialization is done. If we didn't find any
2894  *      APIC bugs then we can allow the modify fast path
2895  */
2896 
2897 static int __init io_apic_bug_finalize(void)
2898 {
2899 	if (sis_apic_bug == -1)
2900 		sis_apic_bug = 0;
2901 	return 0;
2902 }
2903 
2904 late_initcall(io_apic_bug_finalize);
2905 
2906 static void resume_ioapic_id(int ioapic_id)
2907 {
2908 	unsigned long flags;
2909 	union IO_APIC_reg_00 reg_00;
2910 
2911 
2912 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2913 	reg_00.raw = io_apic_read(ioapic_id, 0);
2914 	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_id)) {
2915 		reg_00.bits.ID = mpc_ioapic_id(ioapic_id);
2916 		io_apic_write(ioapic_id, 0, reg_00.raw);
2917 	}
2918 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2919 }
2920 
2921 static void ioapic_resume(void)
2922 {
2923 	int ioapic_id;
2924 
2925 	for (ioapic_id = nr_ioapics - 1; ioapic_id >= 0; ioapic_id--)
2926 		resume_ioapic_id(ioapic_id);
2927 
2928 	restore_ioapic_entries();
2929 }
2930 
2931 static struct syscore_ops ioapic_syscore_ops = {
2932 	.suspend = save_ioapic_entries,
2933 	.resume = ioapic_resume,
2934 };
2935 
2936 static int __init ioapic_init_ops(void)
2937 {
2938 	register_syscore_ops(&ioapic_syscore_ops);
2939 
2940 	return 0;
2941 }
2942 
2943 device_initcall(ioapic_init_ops);
2944 
2945 /*
2946  * Dynamic irq allocate and deallocation
2947  */
2948 unsigned int create_irq_nr(unsigned int from, int node)
2949 {
2950 	struct irq_cfg *cfg;
2951 	unsigned long flags;
2952 	unsigned int ret = 0;
2953 	int irq;
2954 
2955 	if (from < nr_irqs_gsi)
2956 		from = nr_irqs_gsi;
2957 
2958 	irq = alloc_irq_from(from, node);
2959 	if (irq < 0)
2960 		return 0;
2961 	cfg = alloc_irq_cfg(irq, node);
2962 	if (!cfg) {
2963 		free_irq_at(irq, NULL);
2964 		return 0;
2965 	}
2966 
2967 	raw_spin_lock_irqsave(&vector_lock, flags);
2968 	if (!__assign_irq_vector(irq, cfg, apic->target_cpus()))
2969 		ret = irq;
2970 	raw_spin_unlock_irqrestore(&vector_lock, flags);
2971 
2972 	if (ret) {
2973 		irq_set_chip_data(irq, cfg);
2974 		irq_clear_status_flags(irq, IRQ_NOREQUEST);
2975 	} else {
2976 		free_irq_at(irq, cfg);
2977 	}
2978 	return ret;
2979 }
2980 
2981 int create_irq(void)
2982 {
2983 	int node = cpu_to_node(0);
2984 	unsigned int irq_want;
2985 	int irq;
2986 
2987 	irq_want = nr_irqs_gsi;
2988 	irq = create_irq_nr(irq_want, node);
2989 
2990 	if (irq == 0)
2991 		irq = -1;
2992 
2993 	return irq;
2994 }
2995 
2996 void destroy_irq(unsigned int irq)
2997 {
2998 	struct irq_cfg *cfg = irq_get_chip_data(irq);
2999 	unsigned long flags;
3000 
3001 	irq_set_status_flags(irq, IRQ_NOREQUEST|IRQ_NOPROBE);
3002 
3003 	if (irq_remapped(cfg))
3004 		free_irte(irq);
3005 	raw_spin_lock_irqsave(&vector_lock, flags);
3006 	__clear_irq_vector(irq, cfg);
3007 	raw_spin_unlock_irqrestore(&vector_lock, flags);
3008 	free_irq_at(irq, cfg);
3009 }
3010 
3011 /*
3012  * MSI message composition
3013  */
3014 #ifdef CONFIG_PCI_MSI
3015 static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
3016 			   struct msi_msg *msg, u8 hpet_id)
3017 {
3018 	struct irq_cfg *cfg;
3019 	int err;
3020 	unsigned dest;
3021 
3022 	if (disable_apic)
3023 		return -ENXIO;
3024 
3025 	cfg = irq_cfg(irq);
3026 	err = assign_irq_vector(irq, cfg, apic->target_cpus());
3027 	if (err)
3028 		return err;
3029 
3030 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
3031 
3032 	if (irq_remapped(cfg)) {
3033 		struct irte irte;
3034 		int ir_index;
3035 		u16 sub_handle;
3036 
3037 		ir_index = map_irq_to_irte_handle(irq, &sub_handle);
3038 		BUG_ON(ir_index == -1);
3039 
3040 		prepare_irte(&irte, cfg->vector, dest);
3041 
3042 		/* Set source-id of interrupt request */
3043 		if (pdev)
3044 			set_msi_sid(&irte, pdev);
3045 		else
3046 			set_hpet_sid(&irte, hpet_id);
3047 
3048 		modify_irte(irq, &irte);
3049 
3050 		msg->address_hi = MSI_ADDR_BASE_HI;
3051 		msg->data = sub_handle;
3052 		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
3053 				  MSI_ADDR_IR_SHV |
3054 				  MSI_ADDR_IR_INDEX1(ir_index) |
3055 				  MSI_ADDR_IR_INDEX2(ir_index);
3056 	} else {
3057 		if (x2apic_enabled())
3058 			msg->address_hi = MSI_ADDR_BASE_HI |
3059 					  MSI_ADDR_EXT_DEST_ID(dest);
3060 		else
3061 			msg->address_hi = MSI_ADDR_BASE_HI;
3062 
3063 		msg->address_lo =
3064 			MSI_ADDR_BASE_LO |
3065 			((apic->irq_dest_mode == 0) ?
3066 				MSI_ADDR_DEST_MODE_PHYSICAL:
3067 				MSI_ADDR_DEST_MODE_LOGICAL) |
3068 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3069 				MSI_ADDR_REDIRECTION_CPU:
3070 				MSI_ADDR_REDIRECTION_LOWPRI) |
3071 			MSI_ADDR_DEST_ID(dest);
3072 
3073 		msg->data =
3074 			MSI_DATA_TRIGGER_EDGE |
3075 			MSI_DATA_LEVEL_ASSERT |
3076 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3077 				MSI_DATA_DELIVERY_FIXED:
3078 				MSI_DATA_DELIVERY_LOWPRI) |
3079 			MSI_DATA_VECTOR(cfg->vector);
3080 	}
3081 	return err;
3082 }
3083 
3084 #ifdef CONFIG_SMP
3085 static int
3086 msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
3087 {
3088 	struct irq_cfg *cfg = data->chip_data;
3089 	struct msi_msg msg;
3090 	unsigned int dest;
3091 
3092 	if (__ioapic_set_affinity(data, mask, &dest))
3093 		return -1;
3094 
3095 	__get_cached_msi_msg(data->msi_desc, &msg);
3096 
3097 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3098 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3099 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3100 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3101 
3102 	__write_msi_msg(data->msi_desc, &msg);
3103 
3104 	return 0;
3105 }
3106 #ifdef CONFIG_INTR_REMAP
3107 /*
3108  * Migrate the MSI irq to another cpumask. This migration is
3109  * done in the process context using interrupt-remapping hardware.
3110  */
3111 static int
3112 ir_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
3113 		    bool force)
3114 {
3115 	struct irq_cfg *cfg = data->chip_data;
3116 	unsigned int dest, irq = data->irq;
3117 	struct irte irte;
3118 
3119 	if (get_irte(irq, &irte))
3120 		return -1;
3121 
3122 	if (__ioapic_set_affinity(data, mask, &dest))
3123 		return -1;
3124 
3125 	irte.vector = cfg->vector;
3126 	irte.dest_id = IRTE_DEST(dest);
3127 
3128 	/*
3129 	 * atomically update the IRTE with the new destination and vector.
3130 	 */
3131 	modify_irte(irq, &irte);
3132 
3133 	/*
3134 	 * After this point, all the interrupts will start arriving
3135 	 * at the new destination. So, time to cleanup the previous
3136 	 * vector allocation.
3137 	 */
3138 	if (cfg->move_in_progress)
3139 		send_cleanup_vector(cfg);
3140 
3141 	return 0;
3142 }
3143 
3144 #endif
3145 #endif /* CONFIG_SMP */
3146 
3147 /*
3148  * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
3149  * which implement the MSI or MSI-X Capability Structure.
3150  */
3151 static struct irq_chip msi_chip = {
3152 	.name			= "PCI-MSI",
3153 	.irq_unmask		= unmask_msi_irq,
3154 	.irq_mask		= mask_msi_irq,
3155 	.irq_ack		= ack_apic_edge,
3156 #ifdef CONFIG_SMP
3157 	.irq_set_affinity	= msi_set_affinity,
3158 #endif
3159 	.irq_retrigger		= ioapic_retrigger_irq,
3160 };
3161 
3162 static struct irq_chip msi_ir_chip = {
3163 	.name			= "IR-PCI-MSI",
3164 	.irq_unmask		= unmask_msi_irq,
3165 	.irq_mask		= mask_msi_irq,
3166 #ifdef CONFIG_INTR_REMAP
3167 	.irq_ack		= ir_ack_apic_edge,
3168 #ifdef CONFIG_SMP
3169 	.irq_set_affinity	= ir_msi_set_affinity,
3170 #endif
3171 #endif
3172 	.irq_retrigger		= ioapic_retrigger_irq,
3173 };
3174 
3175 /*
3176  * Map the PCI dev to the corresponding remapping hardware unit
3177  * and allocate 'nvec' consecutive interrupt-remapping table entries
3178  * in it.
3179  */
3180 static int msi_alloc_irte(struct pci_dev *dev, int irq, int nvec)
3181 {
3182 	struct intel_iommu *iommu;
3183 	int index;
3184 
3185 	iommu = map_dev_to_ir(dev);
3186 	if (!iommu) {
3187 		printk(KERN_ERR
3188 		       "Unable to map PCI %s to iommu\n", pci_name(dev));
3189 		return -ENOENT;
3190 	}
3191 
3192 	index = alloc_irte(iommu, irq, nvec);
3193 	if (index < 0) {
3194 		printk(KERN_ERR
3195 		       "Unable to allocate %d IRTE for PCI %s\n", nvec,
3196 		       pci_name(dev));
3197 		return -ENOSPC;
3198 	}
3199 	return index;
3200 }
3201 
3202 static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int irq)
3203 {
3204 	struct irq_chip *chip = &msi_chip;
3205 	struct msi_msg msg;
3206 	int ret;
3207 
3208 	ret = msi_compose_msg(dev, irq, &msg, -1);
3209 	if (ret < 0)
3210 		return ret;
3211 
3212 	irq_set_msi_desc(irq, msidesc);
3213 	write_msi_msg(irq, &msg);
3214 
3215 	if (irq_remapped(irq_get_chip_data(irq))) {
3216 		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
3217 		chip = &msi_ir_chip;
3218 	}
3219 
3220 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
3221 
3222 	dev_printk(KERN_DEBUG, &dev->dev, "irq %d for MSI/MSI-X\n", irq);
3223 
3224 	return 0;
3225 }
3226 
3227 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
3228 {
3229 	int node, ret, sub_handle, index = 0;
3230 	unsigned int irq, irq_want;
3231 	struct msi_desc *msidesc;
3232 	struct intel_iommu *iommu = NULL;
3233 
3234 	/* x86 doesn't support multiple MSI yet */
3235 	if (type == PCI_CAP_ID_MSI && nvec > 1)
3236 		return 1;
3237 
3238 	node = dev_to_node(&dev->dev);
3239 	irq_want = nr_irqs_gsi;
3240 	sub_handle = 0;
3241 	list_for_each_entry(msidesc, &dev->msi_list, list) {
3242 		irq = create_irq_nr(irq_want, node);
3243 		if (irq == 0)
3244 			return -1;
3245 		irq_want = irq + 1;
3246 		if (!intr_remapping_enabled)
3247 			goto no_ir;
3248 
3249 		if (!sub_handle) {
3250 			/*
3251 			 * allocate the consecutive block of IRTE's
3252 			 * for 'nvec'
3253 			 */
3254 			index = msi_alloc_irte(dev, irq, nvec);
3255 			if (index < 0) {
3256 				ret = index;
3257 				goto error;
3258 			}
3259 		} else {
3260 			iommu = map_dev_to_ir(dev);
3261 			if (!iommu) {
3262 				ret = -ENOENT;
3263 				goto error;
3264 			}
3265 			/*
3266 			 * setup the mapping between the irq and the IRTE
3267 			 * base index, the sub_handle pointing to the
3268 			 * appropriate interrupt remap table entry.
3269 			 */
3270 			set_irte_irq(irq, iommu, index, sub_handle);
3271 		}
3272 no_ir:
3273 		ret = setup_msi_irq(dev, msidesc, irq);
3274 		if (ret < 0)
3275 			goto error;
3276 		sub_handle++;
3277 	}
3278 	return 0;
3279 
3280 error:
3281 	destroy_irq(irq);
3282 	return ret;
3283 }
3284 
3285 void native_teardown_msi_irq(unsigned int irq)
3286 {
3287 	destroy_irq(irq);
3288 }
3289 
3290 #if defined (CONFIG_DMAR) || defined (CONFIG_INTR_REMAP)
3291 #ifdef CONFIG_SMP
3292 static int
3293 dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
3294 		      bool force)
3295 {
3296 	struct irq_cfg *cfg = data->chip_data;
3297 	unsigned int dest, irq = data->irq;
3298 	struct msi_msg msg;
3299 
3300 	if (__ioapic_set_affinity(data, mask, &dest))
3301 		return -1;
3302 
3303 	dmar_msi_read(irq, &msg);
3304 
3305 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3306 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3307 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3308 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3309 	msg.address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(dest);
3310 
3311 	dmar_msi_write(irq, &msg);
3312 
3313 	return 0;
3314 }
3315 
3316 #endif /* CONFIG_SMP */
3317 
3318 static struct irq_chip dmar_msi_type = {
3319 	.name			= "DMAR_MSI",
3320 	.irq_unmask		= dmar_msi_unmask,
3321 	.irq_mask		= dmar_msi_mask,
3322 	.irq_ack		= ack_apic_edge,
3323 #ifdef CONFIG_SMP
3324 	.irq_set_affinity	= dmar_msi_set_affinity,
3325 #endif
3326 	.irq_retrigger		= ioapic_retrigger_irq,
3327 };
3328 
3329 int arch_setup_dmar_msi(unsigned int irq)
3330 {
3331 	int ret;
3332 	struct msi_msg msg;
3333 
3334 	ret = msi_compose_msg(NULL, irq, &msg, -1);
3335 	if (ret < 0)
3336 		return ret;
3337 	dmar_msi_write(irq, &msg);
3338 	irq_set_chip_and_handler_name(irq, &dmar_msi_type, handle_edge_irq,
3339 				      "edge");
3340 	return 0;
3341 }
3342 #endif
3343 
3344 #ifdef CONFIG_HPET_TIMER
3345 
3346 #ifdef CONFIG_SMP
3347 static int hpet_msi_set_affinity(struct irq_data *data,
3348 				 const struct cpumask *mask, bool force)
3349 {
3350 	struct irq_cfg *cfg = data->chip_data;
3351 	struct msi_msg msg;
3352 	unsigned int dest;
3353 
3354 	if (__ioapic_set_affinity(data, mask, &dest))
3355 		return -1;
3356 
3357 	hpet_msi_read(data->handler_data, &msg);
3358 
3359 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3360 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3361 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3362 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3363 
3364 	hpet_msi_write(data->handler_data, &msg);
3365 
3366 	return 0;
3367 }
3368 
3369 #endif /* CONFIG_SMP */
3370 
3371 static struct irq_chip ir_hpet_msi_type = {
3372 	.name			= "IR-HPET_MSI",
3373 	.irq_unmask		= hpet_msi_unmask,
3374 	.irq_mask		= hpet_msi_mask,
3375 #ifdef CONFIG_INTR_REMAP
3376 	.irq_ack		= ir_ack_apic_edge,
3377 #ifdef CONFIG_SMP
3378 	.irq_set_affinity	= ir_msi_set_affinity,
3379 #endif
3380 #endif
3381 	.irq_retrigger		= ioapic_retrigger_irq,
3382 };
3383 
3384 static struct irq_chip hpet_msi_type = {
3385 	.name = "HPET_MSI",
3386 	.irq_unmask = hpet_msi_unmask,
3387 	.irq_mask = hpet_msi_mask,
3388 	.irq_ack = ack_apic_edge,
3389 #ifdef CONFIG_SMP
3390 	.irq_set_affinity = hpet_msi_set_affinity,
3391 #endif
3392 	.irq_retrigger = ioapic_retrigger_irq,
3393 };
3394 
3395 int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
3396 {
3397 	struct irq_chip *chip = &hpet_msi_type;
3398 	struct msi_msg msg;
3399 	int ret;
3400 
3401 	if (intr_remapping_enabled) {
3402 		struct intel_iommu *iommu = map_hpet_to_ir(id);
3403 		int index;
3404 
3405 		if (!iommu)
3406 			return -1;
3407 
3408 		index = alloc_irte(iommu, irq, 1);
3409 		if (index < 0)
3410 			return -1;
3411 	}
3412 
3413 	ret = msi_compose_msg(NULL, irq, &msg, id);
3414 	if (ret < 0)
3415 		return ret;
3416 
3417 	hpet_msi_write(irq_get_handler_data(irq), &msg);
3418 	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
3419 	if (irq_remapped(irq_get_chip_data(irq)))
3420 		chip = &ir_hpet_msi_type;
3421 
3422 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
3423 	return 0;
3424 }
3425 #endif
3426 
3427 #endif /* CONFIG_PCI_MSI */
3428 /*
3429  * Hypertransport interrupt support
3430  */
3431 #ifdef CONFIG_HT_IRQ
3432 
3433 #ifdef CONFIG_SMP
3434 
3435 static void target_ht_irq(unsigned int irq, unsigned int dest, u8 vector)
3436 {
3437 	struct ht_irq_msg msg;
3438 	fetch_ht_irq_msg(irq, &msg);
3439 
3440 	msg.address_lo &= ~(HT_IRQ_LOW_VECTOR_MASK | HT_IRQ_LOW_DEST_ID_MASK);
3441 	msg.address_hi &= ~(HT_IRQ_HIGH_DEST_ID_MASK);
3442 
3443 	msg.address_lo |= HT_IRQ_LOW_VECTOR(vector) | HT_IRQ_LOW_DEST_ID(dest);
3444 	msg.address_hi |= HT_IRQ_HIGH_DEST_ID(dest);
3445 
3446 	write_ht_irq_msg(irq, &msg);
3447 }
3448 
3449 static int
3450 ht_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
3451 {
3452 	struct irq_cfg *cfg = data->chip_data;
3453 	unsigned int dest;
3454 
3455 	if (__ioapic_set_affinity(data, mask, &dest))
3456 		return -1;
3457 
3458 	target_ht_irq(data->irq, dest, cfg->vector);
3459 	return 0;
3460 }
3461 
3462 #endif
3463 
3464 static struct irq_chip ht_irq_chip = {
3465 	.name			= "PCI-HT",
3466 	.irq_mask		= mask_ht_irq,
3467 	.irq_unmask		= unmask_ht_irq,
3468 	.irq_ack		= ack_apic_edge,
3469 #ifdef CONFIG_SMP
3470 	.irq_set_affinity	= ht_set_affinity,
3471 #endif
3472 	.irq_retrigger		= ioapic_retrigger_irq,
3473 };
3474 
3475 int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
3476 {
3477 	struct irq_cfg *cfg;
3478 	int err;
3479 
3480 	if (disable_apic)
3481 		return -ENXIO;
3482 
3483 	cfg = irq_cfg(irq);
3484 	err = assign_irq_vector(irq, cfg, apic->target_cpus());
3485 	if (!err) {
3486 		struct ht_irq_msg msg;
3487 		unsigned dest;
3488 
3489 		dest = apic->cpu_mask_to_apicid_and(cfg->domain,
3490 						    apic->target_cpus());
3491 
3492 		msg.address_hi = HT_IRQ_HIGH_DEST_ID(dest);
3493 
3494 		msg.address_lo =
3495 			HT_IRQ_LOW_BASE |
3496 			HT_IRQ_LOW_DEST_ID(dest) |
3497 			HT_IRQ_LOW_VECTOR(cfg->vector) |
3498 			((apic->irq_dest_mode == 0) ?
3499 				HT_IRQ_LOW_DM_PHYSICAL :
3500 				HT_IRQ_LOW_DM_LOGICAL) |
3501 			HT_IRQ_LOW_RQEOI_EDGE |
3502 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3503 				HT_IRQ_LOW_MT_FIXED :
3504 				HT_IRQ_LOW_MT_ARBITRATED) |
3505 			HT_IRQ_LOW_IRQ_MASKED;
3506 
3507 		write_ht_irq_msg(irq, &msg);
3508 
3509 		irq_set_chip_and_handler_name(irq, &ht_irq_chip,
3510 					      handle_edge_irq, "edge");
3511 
3512 		dev_printk(KERN_DEBUG, &dev->dev, "irq %d for HT\n", irq);
3513 	}
3514 	return err;
3515 }
3516 #endif /* CONFIG_HT_IRQ */
3517 
3518 static int
3519 io_apic_setup_irq_pin(unsigned int irq, int node, struct io_apic_irq_attr *attr)
3520 {
3521 	struct irq_cfg *cfg = alloc_irq_and_cfg_at(irq, node);
3522 	int ret;
3523 
3524 	if (!cfg)
3525 		return -EINVAL;
3526 	ret = __add_pin_to_irq_node(cfg, node, attr->ioapic, attr->ioapic_pin);
3527 	if (!ret)
3528 		setup_ioapic_irq(attr->ioapic, attr->ioapic_pin, irq, cfg,
3529 				 attr->trigger, attr->polarity);
3530 	return ret;
3531 }
3532 
3533 int io_apic_setup_irq_pin_once(unsigned int irq, int node,
3534 			       struct io_apic_irq_attr *attr)
3535 {
3536 	unsigned int id = attr->ioapic, pin = attr->ioapic_pin;
3537 	int ret;
3538 
3539 	/* Avoid redundant programming */
3540 	if (test_bit(pin, ioapics[id].pin_programmed)) {
3541 		pr_debug("Pin %d-%d already programmed\n",
3542 			 mpc_ioapic_id(id), pin);
3543 		return 0;
3544 	}
3545 	ret = io_apic_setup_irq_pin(irq, node, attr);
3546 	if (!ret)
3547 		set_bit(pin, ioapics[id].pin_programmed);
3548 	return ret;
3549 }
3550 
3551 static int __init io_apic_get_redir_entries(int ioapic)
3552 {
3553 	union IO_APIC_reg_01	reg_01;
3554 	unsigned long flags;
3555 
3556 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3557 	reg_01.raw = io_apic_read(ioapic, 1);
3558 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3559 
3560 	/* The register returns the maximum index redir index
3561 	 * supported, which is one less than the total number of redir
3562 	 * entries.
3563 	 */
3564 	return reg_01.bits.entries + 1;
3565 }
3566 
3567 static void __init probe_nr_irqs_gsi(void)
3568 {
3569 	int nr;
3570 
3571 	nr = gsi_top + NR_IRQS_LEGACY;
3572 	if (nr > nr_irqs_gsi)
3573 		nr_irqs_gsi = nr;
3574 
3575 	printk(KERN_DEBUG "nr_irqs_gsi: %d\n", nr_irqs_gsi);
3576 }
3577 
3578 int get_nr_irqs_gsi(void)
3579 {
3580 	return nr_irqs_gsi;
3581 }
3582 
3583 #ifdef CONFIG_SPARSE_IRQ
3584 int __init arch_probe_nr_irqs(void)
3585 {
3586 	int nr;
3587 
3588 	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
3589 		nr_irqs = NR_VECTORS * nr_cpu_ids;
3590 
3591 	nr = nr_irqs_gsi + 8 * nr_cpu_ids;
3592 #if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
3593 	/*
3594 	 * for MSI and HT dyn irq
3595 	 */
3596 	nr += nr_irqs_gsi * 16;
3597 #endif
3598 	if (nr < nr_irqs)
3599 		nr_irqs = nr;
3600 
3601 	return NR_IRQS_LEGACY;
3602 }
3603 #endif
3604 
3605 int io_apic_set_pci_routing(struct device *dev, int irq,
3606 			    struct io_apic_irq_attr *irq_attr)
3607 {
3608 	int node;
3609 
3610 	if (!IO_APIC_IRQ(irq)) {
3611 		apic_printk(APIC_QUIET,KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
3612 			    irq_attr->ioapic);
3613 		return -EINVAL;
3614 	}
3615 
3616 	node = dev ? dev_to_node(dev) : cpu_to_node(0);
3617 
3618 	return io_apic_setup_irq_pin_once(irq, node, irq_attr);
3619 }
3620 
3621 #ifdef CONFIG_X86_32
3622 static int __init io_apic_get_unique_id(int ioapic, int apic_id)
3623 {
3624 	union IO_APIC_reg_00 reg_00;
3625 	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
3626 	physid_mask_t tmp;
3627 	unsigned long flags;
3628 	int i = 0;
3629 
3630 	/*
3631 	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
3632 	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
3633 	 * supports up to 16 on one shared APIC bus.
3634 	 *
3635 	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
3636 	 *      advantage of new APIC bus architecture.
3637 	 */
3638 
3639 	if (physids_empty(apic_id_map))
3640 		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
3641 
3642 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3643 	reg_00.raw = io_apic_read(ioapic, 0);
3644 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3645 
3646 	if (apic_id >= get_physical_broadcast()) {
3647 		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
3648 			"%d\n", ioapic, apic_id, reg_00.bits.ID);
3649 		apic_id = reg_00.bits.ID;
3650 	}
3651 
3652 	/*
3653 	 * Every APIC in a system must have a unique ID or we get lots of nice
3654 	 * 'stuck on smp_invalidate_needed IPI wait' messages.
3655 	 */
3656 	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
3657 
3658 		for (i = 0; i < get_physical_broadcast(); i++) {
3659 			if (!apic->check_apicid_used(&apic_id_map, i))
3660 				break;
3661 		}
3662 
3663 		if (i == get_physical_broadcast())
3664 			panic("Max apic_id exceeded!\n");
3665 
3666 		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
3667 			"trying %d\n", ioapic, apic_id, i);
3668 
3669 		apic_id = i;
3670 	}
3671 
3672 	apic->apicid_to_cpu_present(apic_id, &tmp);
3673 	physids_or(apic_id_map, apic_id_map, tmp);
3674 
3675 	if (reg_00.bits.ID != apic_id) {
3676 		reg_00.bits.ID = apic_id;
3677 
3678 		raw_spin_lock_irqsave(&ioapic_lock, flags);
3679 		io_apic_write(ioapic, 0, reg_00.raw);
3680 		reg_00.raw = io_apic_read(ioapic, 0);
3681 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3682 
3683 		/* Sanity check */
3684 		if (reg_00.bits.ID != apic_id) {
3685 			printk("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
3686 			return -1;
3687 		}
3688 	}
3689 
3690 	apic_printk(APIC_VERBOSE, KERN_INFO
3691 			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
3692 
3693 	return apic_id;
3694 }
3695 
3696 static u8 __init io_apic_unique_id(u8 id)
3697 {
3698 	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
3699 	    !APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
3700 		return io_apic_get_unique_id(nr_ioapics, id);
3701 	else
3702 		return id;
3703 }
3704 #else
3705 static u8 __init io_apic_unique_id(u8 id)
3706 {
3707 	int i;
3708 	DECLARE_BITMAP(used, 256);
3709 
3710 	bitmap_zero(used, 256);
3711 	for (i = 0; i < nr_ioapics; i++) {
3712 		__set_bit(mpc_ioapic_id(i), used);
3713 	}
3714 	if (!test_bit(id, used))
3715 		return id;
3716 	return find_first_zero_bit(used, 256);
3717 }
3718 #endif
3719 
3720 static int __init io_apic_get_version(int ioapic)
3721 {
3722 	union IO_APIC_reg_01	reg_01;
3723 	unsigned long flags;
3724 
3725 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3726 	reg_01.raw = io_apic_read(ioapic, 1);
3727 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3728 
3729 	return reg_01.bits.version;
3730 }
3731 
3732 int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity)
3733 {
3734 	int ioapic, pin, idx;
3735 
3736 	if (skip_ioapic_setup)
3737 		return -1;
3738 
3739 	ioapic = mp_find_ioapic(gsi);
3740 	if (ioapic < 0)
3741 		return -1;
3742 
3743 	pin = mp_find_ioapic_pin(ioapic, gsi);
3744 	if (pin < 0)
3745 		return -1;
3746 
3747 	idx = find_irq_entry(ioapic, pin, mp_INT);
3748 	if (idx < 0)
3749 		return -1;
3750 
3751 	*trigger = irq_trigger(idx);
3752 	*polarity = irq_polarity(idx);
3753 	return 0;
3754 }
3755 
3756 /*
3757  * This function currently is only a helper for the i386 smp boot process where
3758  * we need to reprogram the ioredtbls to cater for the cpus which have come online
3759  * so mask in all cases should simply be apic->target_cpus()
3760  */
3761 #ifdef CONFIG_SMP
3762 void __init setup_ioapic_dest(void)
3763 {
3764 	int pin, ioapic, irq, irq_entry;
3765 	const struct cpumask *mask;
3766 	struct irq_data *idata;
3767 
3768 	if (skip_ioapic_setup == 1)
3769 		return;
3770 
3771 	for (ioapic = 0; ioapic < nr_ioapics; ioapic++)
3772 	for (pin = 0; pin < ioapics[ioapic].nr_registers; pin++) {
3773 		irq_entry = find_irq_entry(ioapic, pin, mp_INT);
3774 		if (irq_entry == -1)
3775 			continue;
3776 		irq = pin_2_irq(irq_entry, ioapic, pin);
3777 
3778 		if ((ioapic > 0) && (irq > 16))
3779 			continue;
3780 
3781 		idata = irq_get_irq_data(irq);
3782 
3783 		/*
3784 		 * Honour affinities which have been set in early boot
3785 		 */
3786 		if (!irqd_can_balance(idata) || irqd_affinity_was_set(idata))
3787 			mask = idata->affinity;
3788 		else
3789 			mask = apic->target_cpus();
3790 
3791 		if (intr_remapping_enabled)
3792 			ir_ioapic_set_affinity(idata, mask, false);
3793 		else
3794 			ioapic_set_affinity(idata, mask, false);
3795 	}
3796 
3797 }
3798 #endif
3799 
3800 #define IOAPIC_RESOURCE_NAME_SIZE 11
3801 
3802 static struct resource *ioapic_resources;
3803 
3804 static struct resource * __init ioapic_setup_resources(int nr_ioapics)
3805 {
3806 	unsigned long n;
3807 	struct resource *res;
3808 	char *mem;
3809 	int i;
3810 
3811 	if (nr_ioapics <= 0)
3812 		return NULL;
3813 
3814 	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
3815 	n *= nr_ioapics;
3816 
3817 	mem = alloc_bootmem(n);
3818 	res = (void *)mem;
3819 
3820 	mem += sizeof(struct resource) * nr_ioapics;
3821 
3822 	for (i = 0; i < nr_ioapics; i++) {
3823 		res[i].name = mem;
3824 		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
3825 		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
3826 		mem += IOAPIC_RESOURCE_NAME_SIZE;
3827 	}
3828 
3829 	ioapic_resources = res;
3830 
3831 	return res;
3832 }
3833 
3834 void __init ioapic_and_gsi_init(void)
3835 {
3836 	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
3837 	struct resource *ioapic_res;
3838 	int i;
3839 
3840 	ioapic_res = ioapic_setup_resources(nr_ioapics);
3841 	for (i = 0; i < nr_ioapics; i++) {
3842 		if (smp_found_config) {
3843 			ioapic_phys = mpc_ioapic_addr(i);
3844 #ifdef CONFIG_X86_32
3845 			if (!ioapic_phys) {
3846 				printk(KERN_ERR
3847 				       "WARNING: bogus zero IO-APIC "
3848 				       "address found in MPTABLE, "
3849 				       "disabling IO/APIC support!\n");
3850 				smp_found_config = 0;
3851 				skip_ioapic_setup = 1;
3852 				goto fake_ioapic_page;
3853 			}
3854 #endif
3855 		} else {
3856 #ifdef CONFIG_X86_32
3857 fake_ioapic_page:
3858 #endif
3859 			ioapic_phys = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
3860 			ioapic_phys = __pa(ioapic_phys);
3861 		}
3862 		set_fixmap_nocache(idx, ioapic_phys);
3863 		apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08lx (%08lx)\n",
3864 			__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK),
3865 			ioapic_phys);
3866 		idx++;
3867 
3868 		ioapic_res->start = ioapic_phys;
3869 		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
3870 		ioapic_res++;
3871 	}
3872 
3873 	probe_nr_irqs_gsi();
3874 }
3875 
3876 void __init ioapic_insert_resources(void)
3877 {
3878 	int i;
3879 	struct resource *r = ioapic_resources;
3880 
3881 	if (!r) {
3882 		if (nr_ioapics > 0)
3883 			printk(KERN_ERR
3884 				"IO APIC resources couldn't be allocated.\n");
3885 		return;
3886 	}
3887 
3888 	for (i = 0; i < nr_ioapics; i++) {
3889 		insert_resource(&iomem_resource, r);
3890 		r++;
3891 	}
3892 }
3893 
3894 int mp_find_ioapic(u32 gsi)
3895 {
3896 	int i = 0;
3897 
3898 	if (nr_ioapics == 0)
3899 		return -1;
3900 
3901 	/* Find the IOAPIC that manages this GSI. */
3902 	for (i = 0; i < nr_ioapics; i++) {
3903 		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
3904 		if ((gsi >= gsi_cfg->gsi_base)
3905 		    && (gsi <= gsi_cfg->gsi_end))
3906 			return i;
3907 	}
3908 
3909 	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
3910 	return -1;
3911 }
3912 
3913 int mp_find_ioapic_pin(int ioapic, u32 gsi)
3914 {
3915 	struct mp_ioapic_gsi *gsi_cfg;
3916 
3917 	if (WARN_ON(ioapic == -1))
3918 		return -1;
3919 
3920 	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
3921 	if (WARN_ON(gsi > gsi_cfg->gsi_end))
3922 		return -1;
3923 
3924 	return gsi - gsi_cfg->gsi_base;
3925 }
3926 
3927 static __init int bad_ioapic(unsigned long address)
3928 {
3929 	if (nr_ioapics >= MAX_IO_APICS) {
3930 		printk(KERN_WARNING "WARNING: Max # of I/O APICs (%d) exceeded "
3931 		       "(found %d), skipping\n", MAX_IO_APICS, nr_ioapics);
3932 		return 1;
3933 	}
3934 	if (!address) {
3935 		printk(KERN_WARNING "WARNING: Bogus (zero) I/O APIC address"
3936 		       " found in table, skipping!\n");
3937 		return 1;
3938 	}
3939 	return 0;
3940 }
3941 
3942 void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
3943 {
3944 	int idx = 0;
3945 	int entries;
3946 	struct mp_ioapic_gsi *gsi_cfg;
3947 
3948 	if (bad_ioapic(address))
3949 		return;
3950 
3951 	idx = nr_ioapics;
3952 
3953 	ioapics[idx].mp_config.type = MP_IOAPIC;
3954 	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
3955 	ioapics[idx].mp_config.apicaddr = address;
3956 
3957 	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
3958 	ioapics[idx].mp_config.apicid = io_apic_unique_id(id);
3959 	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
3960 
3961 	/*
3962 	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
3963 	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
3964 	 */
3965 	entries = io_apic_get_redir_entries(idx);
3966 	gsi_cfg = mp_ioapic_gsi_routing(idx);
3967 	gsi_cfg->gsi_base = gsi_base;
3968 	gsi_cfg->gsi_end = gsi_base + entries - 1;
3969 
3970 	/*
3971 	 * The number of IO-APIC IRQ registers (== #pins):
3972 	 */
3973 	ioapics[idx].nr_registers = entries;
3974 
3975 	if (gsi_cfg->gsi_end >= gsi_top)
3976 		gsi_top = gsi_cfg->gsi_end + 1;
3977 
3978 	printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%x, "
3979 	       "GSI %d-%d\n", idx, mpc_ioapic_id(idx),
3980 	       mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
3981 	       gsi_cfg->gsi_base, gsi_cfg->gsi_end);
3982 
3983 	nr_ioapics++;
3984 }
3985 
3986 /* Enable IOAPIC early just for system timer */
3987 void __init pre_init_apic_IRQ0(void)
3988 {
3989 	struct io_apic_irq_attr attr = { 0, 0, 0, 0 };
3990 
3991 	printk(KERN_INFO "Early APIC setup for system timer0\n");
3992 #ifndef CONFIG_SMP
3993 	physid_set_mask_of_physid(boot_cpu_physical_apicid,
3994 					 &phys_cpu_present_map);
3995 #endif
3996 	setup_local_APIC();
3997 
3998 	io_apic_setup_irq_pin(0, 0, &attr);
3999 	irq_set_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq,
4000 				      "edge");
4001 }
4002