xref: /openbmc/linux/arch/x86/kernel/apic/io_apic.c (revision e4aff811)
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 
1299 		apic_printk(APIC_VERBOSE, KERN_DEBUG "IOAPIC[%d]: "
1300 			"Set IRTE entry (P:%d FPD:%d Dst_Mode:%d "
1301 			"Redir_hint:%d Trig_Mode:%d Dlvry_Mode:%X "
1302 			"Avail:%X Vector:%02X Dest:%08X "
1303 			"SID:%04X SQ:%X SVT:%X)\n",
1304 			apic_id, irte.present, irte.fpd, irte.dst_mode,
1305 			irte.redir_hint, irte.trigger_mode, irte.dlvry_mode,
1306 			irte.avail, irte.vector, irte.dest_id,
1307 			irte.sid, irte.sq, irte.svt);
1308 	} else {
1309 		entry->delivery_mode = apic->irq_delivery_mode;
1310 		entry->dest_mode = apic->irq_dest_mode;
1311 		entry->dest = destination;
1312 		entry->vector = vector;
1313 	}
1314 
1315 	entry->mask = 0;				/* enable IRQ */
1316 	entry->trigger = trigger;
1317 	entry->polarity = polarity;
1318 
1319 	/* Mask level triggered irqs.
1320 	 * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
1321 	 */
1322 	if (trigger)
1323 		entry->mask = 1;
1324 	return 0;
1325 }
1326 
1327 static void setup_ioapic_irq(unsigned int irq, struct irq_cfg *cfg,
1328 				struct io_apic_irq_attr *attr)
1329 {
1330 	struct IO_APIC_route_entry entry;
1331 	unsigned int dest;
1332 
1333 	if (!IO_APIC_IRQ(irq))
1334 		return;
1335 	/*
1336 	 * For legacy irqs, cfg->domain starts with cpu 0 for legacy
1337 	 * controllers like 8259. Now that IO-APIC can handle this irq, update
1338 	 * the cfg->domain.
1339 	 */
1340 	if (irq < legacy_pic->nr_legacy_irqs && cpumask_test_cpu(0, cfg->domain))
1341 		apic->vector_allocation_domain(0, cfg->domain);
1342 
1343 	if (assign_irq_vector(irq, cfg, apic->target_cpus()))
1344 		return;
1345 
1346 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
1347 
1348 	apic_printk(APIC_VERBOSE,KERN_DEBUG
1349 		    "IOAPIC[%d]: Set routing entry (%d-%d -> 0x%x -> "
1350 		    "IRQ %d Mode:%i Active:%i Dest:%d)\n",
1351 		    attr->ioapic, mpc_ioapic_id(attr->ioapic), attr->ioapic_pin,
1352 		    cfg->vector, irq, attr->trigger, attr->polarity, dest);
1353 
1354 
1355 	if (setup_ioapic_entry(mpc_ioapic_id(attr->ioapic), irq, &entry,
1356 			       dest, attr->trigger, attr->polarity, cfg->vector,
1357 			       attr->ioapic_pin)) {
1358 		printk("Failed to setup ioapic entry for ioapic  %d, pin %d\n",
1359 		       mpc_ioapic_id(attr->ioapic), attr->ioapic_pin);
1360 		__clear_irq_vector(irq, cfg);
1361 		return;
1362 	}
1363 
1364 	ioapic_register_intr(irq, cfg, attr->trigger);
1365 	if (irq < legacy_pic->nr_legacy_irqs)
1366 		legacy_pic->mask(irq);
1367 
1368 	ioapic_write_entry(attr->ioapic, attr->ioapic_pin, entry);
1369 }
1370 
1371 static bool __init io_apic_pin_not_connected(int idx, int apic_id, int pin)
1372 {
1373 	if (idx != -1)
1374 		return false;
1375 
1376 	apic_printk(APIC_VERBOSE, KERN_DEBUG " apic %d pin %d not connected\n",
1377 		    mpc_ioapic_id(apic_id), pin);
1378 	return true;
1379 }
1380 
1381 static void __init __io_apic_setup_irqs(unsigned int apic_id)
1382 {
1383 	int idx, node = cpu_to_node(0);
1384 	struct io_apic_irq_attr attr;
1385 	unsigned int pin, irq;
1386 
1387 	for (pin = 0; pin < ioapics[apic_id].nr_registers; pin++) {
1388 		idx = find_irq_entry(apic_id, pin, mp_INT);
1389 		if (io_apic_pin_not_connected(idx, apic_id, pin))
1390 			continue;
1391 
1392 		irq = pin_2_irq(idx, apic_id, pin);
1393 
1394 		if ((apic_id > 0) && (irq > 16))
1395 			continue;
1396 
1397 		/*
1398 		 * Skip the timer IRQ if there's a quirk handler
1399 		 * installed and if it returns 1:
1400 		 */
1401 		if (apic->multi_timer_check &&
1402 		    apic->multi_timer_check(apic_id, irq))
1403 			continue;
1404 
1405 		set_io_apic_irq_attr(&attr, apic_id, pin, irq_trigger(idx),
1406 				     irq_polarity(idx));
1407 
1408 		io_apic_setup_irq_pin(irq, node, &attr);
1409 	}
1410 }
1411 
1412 static void __init setup_IO_APIC_irqs(void)
1413 {
1414 	unsigned int apic_id;
1415 
1416 	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
1417 
1418 	for (apic_id = 0; apic_id < nr_ioapics; apic_id++)
1419 		__io_apic_setup_irqs(apic_id);
1420 }
1421 
1422 /*
1423  * for the gsit that is not in first ioapic
1424  * but could not use acpi_register_gsi()
1425  * like some special sci in IBM x3330
1426  */
1427 void setup_IO_APIC_irq_extra(u32 gsi)
1428 {
1429 	int apic_id = 0, pin, idx, irq, node = cpu_to_node(0);
1430 	struct io_apic_irq_attr attr;
1431 
1432 	/*
1433 	 * Convert 'gsi' to 'ioapic.pin'.
1434 	 */
1435 	apic_id = mp_find_ioapic(gsi);
1436 	if (apic_id < 0)
1437 		return;
1438 
1439 	pin = mp_find_ioapic_pin(apic_id, gsi);
1440 	idx = find_irq_entry(apic_id, pin, mp_INT);
1441 	if (idx == -1)
1442 		return;
1443 
1444 	irq = pin_2_irq(idx, apic_id, pin);
1445 
1446 	/* Only handle the non legacy irqs on secondary ioapics */
1447 	if (apic_id == 0 || irq < NR_IRQS_LEGACY)
1448 		return;
1449 
1450 	set_io_apic_irq_attr(&attr, apic_id, pin, irq_trigger(idx),
1451 			     irq_polarity(idx));
1452 
1453 	io_apic_setup_irq_pin_once(irq, node, &attr);
1454 }
1455 
1456 /*
1457  * Set up the timer pin, possibly with the 8259A-master behind.
1458  */
1459 static void __init setup_timer_IRQ0_pin(unsigned int apic_id, unsigned int pin,
1460 					int vector)
1461 {
1462 	struct IO_APIC_route_entry entry;
1463 
1464 	if (intr_remapping_enabled)
1465 		return;
1466 
1467 	memset(&entry, 0, sizeof(entry));
1468 
1469 	/*
1470 	 * We use logical delivery to get the timer IRQ
1471 	 * to the first CPU.
1472 	 */
1473 	entry.dest_mode = apic->irq_dest_mode;
1474 	entry.mask = 0;			/* don't mask IRQ for edge */
1475 	entry.dest = apic->cpu_mask_to_apicid(apic->target_cpus());
1476 	entry.delivery_mode = apic->irq_delivery_mode;
1477 	entry.polarity = 0;
1478 	entry.trigger = 0;
1479 	entry.vector = vector;
1480 
1481 	/*
1482 	 * The timer IRQ doesn't have to know that behind the
1483 	 * scene we may have a 8259A-master in AEOI mode ...
1484 	 */
1485 	irq_set_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq,
1486 				      "edge");
1487 
1488 	/*
1489 	 * Add it to the IO-APIC irq-routing table:
1490 	 */
1491 	ioapic_write_entry(apic_id, pin, entry);
1492 }
1493 
1494 
1495 __apicdebuginit(void) print_IO_APIC(void)
1496 {
1497 	int apic, i;
1498 	union IO_APIC_reg_00 reg_00;
1499 	union IO_APIC_reg_01 reg_01;
1500 	union IO_APIC_reg_02 reg_02;
1501 	union IO_APIC_reg_03 reg_03;
1502 	unsigned long flags;
1503 	struct irq_cfg *cfg;
1504 	unsigned int irq;
1505 
1506 	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
1507 	for (i = 0; i < nr_ioapics; i++)
1508 		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
1509 		       mpc_ioapic_id(i), ioapics[i].nr_registers);
1510 
1511 	/*
1512 	 * We are a bit conservative about what we expect.  We have to
1513 	 * know about every hardware change ASAP.
1514 	 */
1515 	printk(KERN_INFO "testing the IO APIC.......................\n");
1516 
1517 	for (apic = 0; apic < nr_ioapics; apic++) {
1518 
1519 	raw_spin_lock_irqsave(&ioapic_lock, flags);
1520 	reg_00.raw = io_apic_read(apic, 0);
1521 	reg_01.raw = io_apic_read(apic, 1);
1522 	if (reg_01.bits.version >= 0x10)
1523 		reg_02.raw = io_apic_read(apic, 2);
1524 	if (reg_01.bits.version >= 0x20)
1525 		reg_03.raw = io_apic_read(apic, 3);
1526 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1527 
1528 	printk("\n");
1529 	printk(KERN_DEBUG "IO APIC #%d......\n", mpc_ioapic_id(apic));
1530 	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
1531 	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
1532 	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
1533 	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
1534 
1535 	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
1536 	printk(KERN_DEBUG ".......     : max redirection entries: %02X\n",
1537 		reg_01.bits.entries);
1538 
1539 	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
1540 	printk(KERN_DEBUG ".......     : IO APIC version: %02X\n",
1541 		reg_01.bits.version);
1542 
1543 	/*
1544 	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
1545 	 * but the value of reg_02 is read as the previous read register
1546 	 * value, so ignore it if reg_02 == reg_01.
1547 	 */
1548 	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
1549 		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
1550 		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
1551 	}
1552 
1553 	/*
1554 	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
1555 	 * or reg_03, but the value of reg_0[23] is read as the previous read
1556 	 * register value, so ignore it if reg_03 == reg_0[12].
1557 	 */
1558 	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
1559 	    reg_03.raw != reg_01.raw) {
1560 		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
1561 		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
1562 	}
1563 
1564 	printk(KERN_DEBUG ".... IRQ redirection table:\n");
1565 
1566 	if (intr_remapping_enabled) {
1567 		printk(KERN_DEBUG " NR Indx Fmt Mask Trig IRR"
1568 			" Pol Stat Indx2 Zero Vect:\n");
1569 	} else {
1570 		printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
1571 			" Stat Dmod Deli Vect:\n");
1572 	}
1573 
1574 	for (i = 0; i <= reg_01.bits.entries; i++) {
1575 		if (intr_remapping_enabled) {
1576 			struct IO_APIC_route_entry entry;
1577 			struct IR_IO_APIC_route_entry *ir_entry;
1578 
1579 			entry = ioapic_read_entry(apic, i);
1580 			ir_entry = (struct IR_IO_APIC_route_entry *) &entry;
1581 			printk(KERN_DEBUG " %02x %04X ",
1582 				i,
1583 				ir_entry->index
1584 			);
1585 			printk("%1d   %1d    %1d    %1d   %1d   "
1586 				"%1d    %1d     %X    %02X\n",
1587 				ir_entry->format,
1588 				ir_entry->mask,
1589 				ir_entry->trigger,
1590 				ir_entry->irr,
1591 				ir_entry->polarity,
1592 				ir_entry->delivery_status,
1593 				ir_entry->index2,
1594 				ir_entry->zero,
1595 				ir_entry->vector
1596 			);
1597 		} else {
1598 			struct IO_APIC_route_entry entry;
1599 
1600 			entry = ioapic_read_entry(apic, i);
1601 			printk(KERN_DEBUG " %02x %02X  ",
1602 				i,
1603 				entry.dest
1604 			);
1605 			printk("%1d    %1d    %1d   %1d   %1d    "
1606 				"%1d    %1d    %02X\n",
1607 				entry.mask,
1608 				entry.trigger,
1609 				entry.irr,
1610 				entry.polarity,
1611 				entry.delivery_status,
1612 				entry.dest_mode,
1613 				entry.delivery_mode,
1614 				entry.vector
1615 			);
1616 		}
1617 	}
1618 	}
1619 
1620 	printk(KERN_DEBUG "IRQ to pin mappings:\n");
1621 	for_each_active_irq(irq) {
1622 		struct irq_pin_list *entry;
1623 
1624 		cfg = irq_get_chip_data(irq);
1625 		if (!cfg)
1626 			continue;
1627 		entry = cfg->irq_2_pin;
1628 		if (!entry)
1629 			continue;
1630 		printk(KERN_DEBUG "IRQ%d ", irq);
1631 		for_each_irq_pin(entry, cfg->irq_2_pin)
1632 			printk("-> %d:%d", entry->apic, entry->pin);
1633 		printk("\n");
1634 	}
1635 
1636 	printk(KERN_INFO ".................................... done.\n");
1637 
1638 	return;
1639 }
1640 
1641 __apicdebuginit(void) print_APIC_field(int base)
1642 {
1643 	int i;
1644 
1645 	printk(KERN_DEBUG);
1646 
1647 	for (i = 0; i < 8; i++)
1648 		printk(KERN_CONT "%08x", apic_read(base + i*0x10));
1649 
1650 	printk(KERN_CONT "\n");
1651 }
1652 
1653 __apicdebuginit(void) print_local_APIC(void *dummy)
1654 {
1655 	unsigned int i, v, ver, maxlvt;
1656 	u64 icr;
1657 
1658 	printk(KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
1659 		smp_processor_id(), hard_smp_processor_id());
1660 	v = apic_read(APIC_ID);
1661 	printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, read_apic_id());
1662 	v = apic_read(APIC_LVR);
1663 	printk(KERN_INFO "... APIC VERSION: %08x\n", v);
1664 	ver = GET_APIC_VERSION(v);
1665 	maxlvt = lapic_get_maxlvt();
1666 
1667 	v = apic_read(APIC_TASKPRI);
1668 	printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
1669 
1670 	if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
1671 		if (!APIC_XAPIC(ver)) {
1672 			v = apic_read(APIC_ARBPRI);
1673 			printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
1674 			       v & APIC_ARBPRI_MASK);
1675 		}
1676 		v = apic_read(APIC_PROCPRI);
1677 		printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
1678 	}
1679 
1680 	/*
1681 	 * Remote read supported only in the 82489DX and local APIC for
1682 	 * Pentium processors.
1683 	 */
1684 	if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
1685 		v = apic_read(APIC_RRR);
1686 		printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
1687 	}
1688 
1689 	v = apic_read(APIC_LDR);
1690 	printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
1691 	if (!x2apic_enabled()) {
1692 		v = apic_read(APIC_DFR);
1693 		printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
1694 	}
1695 	v = apic_read(APIC_SPIV);
1696 	printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);
1697 
1698 	printk(KERN_DEBUG "... APIC ISR field:\n");
1699 	print_APIC_field(APIC_ISR);
1700 	printk(KERN_DEBUG "... APIC TMR field:\n");
1701 	print_APIC_field(APIC_TMR);
1702 	printk(KERN_DEBUG "... APIC IRR field:\n");
1703 	print_APIC_field(APIC_IRR);
1704 
1705 	if (APIC_INTEGRATED(ver)) {             /* !82489DX */
1706 		if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
1707 			apic_write(APIC_ESR, 0);
1708 
1709 		v = apic_read(APIC_ESR);
1710 		printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
1711 	}
1712 
1713 	icr = apic_icr_read();
1714 	printk(KERN_DEBUG "... APIC ICR: %08x\n", (u32)icr);
1715 	printk(KERN_DEBUG "... APIC ICR2: %08x\n", (u32)(icr >> 32));
1716 
1717 	v = apic_read(APIC_LVTT);
1718 	printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);
1719 
1720 	if (maxlvt > 3) {                       /* PC is LVT#4. */
1721 		v = apic_read(APIC_LVTPC);
1722 		printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
1723 	}
1724 	v = apic_read(APIC_LVT0);
1725 	printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
1726 	v = apic_read(APIC_LVT1);
1727 	printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);
1728 
1729 	if (maxlvt > 2) {			/* ERR is LVT#3. */
1730 		v = apic_read(APIC_LVTERR);
1731 		printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
1732 	}
1733 
1734 	v = apic_read(APIC_TMICT);
1735 	printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
1736 	v = apic_read(APIC_TMCCT);
1737 	printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
1738 	v = apic_read(APIC_TDCR);
1739 	printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);
1740 
1741 	if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
1742 		v = apic_read(APIC_EFEAT);
1743 		maxlvt = (v >> 16) & 0xff;
1744 		printk(KERN_DEBUG "... APIC EFEAT: %08x\n", v);
1745 		v = apic_read(APIC_ECTRL);
1746 		printk(KERN_DEBUG "... APIC ECTRL: %08x\n", v);
1747 		for (i = 0; i < maxlvt; i++) {
1748 			v = apic_read(APIC_EILVTn(i));
1749 			printk(KERN_DEBUG "... APIC EILVT%d: %08x\n", i, v);
1750 		}
1751 	}
1752 	printk("\n");
1753 }
1754 
1755 __apicdebuginit(void) print_local_APICs(int maxcpu)
1756 {
1757 	int cpu;
1758 
1759 	if (!maxcpu)
1760 		return;
1761 
1762 	preempt_disable();
1763 	for_each_online_cpu(cpu) {
1764 		if (cpu >= maxcpu)
1765 			break;
1766 		smp_call_function_single(cpu, print_local_APIC, NULL, 1);
1767 	}
1768 	preempt_enable();
1769 }
1770 
1771 __apicdebuginit(void) print_PIC(void)
1772 {
1773 	unsigned int v;
1774 	unsigned long flags;
1775 
1776 	if (!legacy_pic->nr_legacy_irqs)
1777 		return;
1778 
1779 	printk(KERN_DEBUG "\nprinting PIC contents\n");
1780 
1781 	raw_spin_lock_irqsave(&i8259A_lock, flags);
1782 
1783 	v = inb(0xa1) << 8 | inb(0x21);
1784 	printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);
1785 
1786 	v = inb(0xa0) << 8 | inb(0x20);
1787 	printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);
1788 
1789 	outb(0x0b,0xa0);
1790 	outb(0x0b,0x20);
1791 	v = inb(0xa0) << 8 | inb(0x20);
1792 	outb(0x0a,0xa0);
1793 	outb(0x0a,0x20);
1794 
1795 	raw_spin_unlock_irqrestore(&i8259A_lock, flags);
1796 
1797 	printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);
1798 
1799 	v = inb(0x4d1) << 8 | inb(0x4d0);
1800 	printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
1801 }
1802 
1803 static int __initdata show_lapic = 1;
1804 static __init int setup_show_lapic(char *arg)
1805 {
1806 	int num = -1;
1807 
1808 	if (strcmp(arg, "all") == 0) {
1809 		show_lapic = CONFIG_NR_CPUS;
1810 	} else {
1811 		get_option(&arg, &num);
1812 		if (num >= 0)
1813 			show_lapic = num;
1814 	}
1815 
1816 	return 1;
1817 }
1818 __setup("show_lapic=", setup_show_lapic);
1819 
1820 __apicdebuginit(int) print_ICs(void)
1821 {
1822 	if (apic_verbosity == APIC_QUIET)
1823 		return 0;
1824 
1825 	print_PIC();
1826 
1827 	/* don't print out if apic is not there */
1828 	if (!cpu_has_apic && !apic_from_smp_config())
1829 		return 0;
1830 
1831 	print_local_APICs(show_lapic);
1832 	print_IO_APIC();
1833 
1834 	return 0;
1835 }
1836 
1837 late_initcall(print_ICs);
1838 
1839 
1840 /* Where if anywhere is the i8259 connect in external int mode */
1841 static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
1842 
1843 void __init enable_IO_APIC(void)
1844 {
1845 	int i8259_apic, i8259_pin;
1846 	int apic;
1847 
1848 	if (!legacy_pic->nr_legacy_irqs)
1849 		return;
1850 
1851 	for(apic = 0; apic < nr_ioapics; apic++) {
1852 		int pin;
1853 		/* See if any of the pins is in ExtINT mode */
1854 		for (pin = 0; pin < ioapics[apic].nr_registers; pin++) {
1855 			struct IO_APIC_route_entry entry;
1856 			entry = ioapic_read_entry(apic, pin);
1857 
1858 			/* If the interrupt line is enabled and in ExtInt mode
1859 			 * I have found the pin where the i8259 is connected.
1860 			 */
1861 			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
1862 				ioapic_i8259.apic = apic;
1863 				ioapic_i8259.pin  = pin;
1864 				goto found_i8259;
1865 			}
1866 		}
1867 	}
1868  found_i8259:
1869 	/* Look to see what if the MP table has reported the ExtINT */
1870 	/* If we could not find the appropriate pin by looking at the ioapic
1871 	 * the i8259 probably is not connected the ioapic but give the
1872 	 * mptable a chance anyway.
1873 	 */
1874 	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
1875 	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
1876 	/* Trust the MP table if nothing is setup in the hardware */
1877 	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
1878 		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
1879 		ioapic_i8259.pin  = i8259_pin;
1880 		ioapic_i8259.apic = i8259_apic;
1881 	}
1882 	/* Complain if the MP table and the hardware disagree */
1883 	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
1884 		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
1885 	{
1886 		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
1887 	}
1888 
1889 	/*
1890 	 * Do not trust the IO-APIC being empty at bootup
1891 	 */
1892 	clear_IO_APIC();
1893 }
1894 
1895 /*
1896  * Not an __init, needed by the reboot code
1897  */
1898 void disable_IO_APIC(void)
1899 {
1900 	/*
1901 	 * Clear the IO-APIC before rebooting:
1902 	 */
1903 	clear_IO_APIC();
1904 
1905 	if (!legacy_pic->nr_legacy_irqs)
1906 		return;
1907 
1908 	/*
1909 	 * If the i8259 is routed through an IOAPIC
1910 	 * Put that IOAPIC in virtual wire mode
1911 	 * so legacy interrupts can be delivered.
1912 	 *
1913 	 * With interrupt-remapping, for now we will use virtual wire A mode,
1914 	 * as virtual wire B is little complex (need to configure both
1915 	 * IOAPIC RTE as well as interrupt-remapping table entry).
1916 	 * As this gets called during crash dump, keep this simple for now.
1917 	 */
1918 	if (ioapic_i8259.pin != -1 && !intr_remapping_enabled) {
1919 		struct IO_APIC_route_entry entry;
1920 
1921 		memset(&entry, 0, sizeof(entry));
1922 		entry.mask            = 0; /* Enabled */
1923 		entry.trigger         = 0; /* Edge */
1924 		entry.irr             = 0;
1925 		entry.polarity        = 0; /* High */
1926 		entry.delivery_status = 0;
1927 		entry.dest_mode       = 0; /* Physical */
1928 		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
1929 		entry.vector          = 0;
1930 		entry.dest            = read_apic_id();
1931 
1932 		/*
1933 		 * Add it to the IO-APIC irq-routing table:
1934 		 */
1935 		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
1936 	}
1937 
1938 	/*
1939 	 * Use virtual wire A mode when interrupt remapping is enabled.
1940 	 */
1941 	if (cpu_has_apic || apic_from_smp_config())
1942 		disconnect_bsp_APIC(!intr_remapping_enabled &&
1943 				ioapic_i8259.pin != -1);
1944 }
1945 
1946 #ifdef CONFIG_X86_32
1947 /*
1948  * function to set the IO-APIC physical IDs based on the
1949  * values stored in the MPC table.
1950  *
1951  * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
1952  */
1953 void __init setup_ioapic_ids_from_mpc_nocheck(void)
1954 {
1955 	union IO_APIC_reg_00 reg_00;
1956 	physid_mask_t phys_id_present_map;
1957 	int apic_id;
1958 	int i;
1959 	unsigned char old_id;
1960 	unsigned long flags;
1961 
1962 	/*
1963 	 * This is broken; anything with a real cpu count has to
1964 	 * circumvent this idiocy regardless.
1965 	 */
1966 	apic->ioapic_phys_id_map(&phys_cpu_present_map, &phys_id_present_map);
1967 
1968 	/*
1969 	 * Set the IOAPIC ID to the value stored in the MPC table.
1970 	 */
1971 	for (apic_id = 0; apic_id < nr_ioapics; apic_id++) {
1972 
1973 		/* Read the register 0 value */
1974 		raw_spin_lock_irqsave(&ioapic_lock, flags);
1975 		reg_00.raw = io_apic_read(apic_id, 0);
1976 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
1977 
1978 		old_id = mpc_ioapic_id(apic_id);
1979 
1980 		if (mpc_ioapic_id(apic_id) >= get_physical_broadcast()) {
1981 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
1982 				apic_id, mpc_ioapic_id(apic_id));
1983 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
1984 				reg_00.bits.ID);
1985 			ioapics[apic_id].mp_config.apicid = reg_00.bits.ID;
1986 		}
1987 
1988 		/*
1989 		 * Sanity check, is the ID really free? Every APIC in a
1990 		 * system must have a unique ID or we get lots of nice
1991 		 * 'stuck on smp_invalidate_needed IPI wait' messages.
1992 		 */
1993 		if (apic->check_apicid_used(&phys_id_present_map,
1994 					    mpc_ioapic_id(apic_id))) {
1995 			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
1996 				apic_id, mpc_ioapic_id(apic_id));
1997 			for (i = 0; i < get_physical_broadcast(); i++)
1998 				if (!physid_isset(i, phys_id_present_map))
1999 					break;
2000 			if (i >= get_physical_broadcast())
2001 				panic("Max APIC ID exceeded!\n");
2002 			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
2003 				i);
2004 			physid_set(i, phys_id_present_map);
2005 			ioapics[apic_id].mp_config.apicid = i;
2006 		} else {
2007 			physid_mask_t tmp;
2008 			apic->apicid_to_cpu_present(mpc_ioapic_id(apic_id),
2009 						    &tmp);
2010 			apic_printk(APIC_VERBOSE, "Setting %d in the "
2011 					"phys_id_present_map\n",
2012 					mpc_ioapic_id(apic_id));
2013 			physids_or(phys_id_present_map, phys_id_present_map, tmp);
2014 		}
2015 
2016 		/*
2017 		 * We need to adjust the IRQ routing table
2018 		 * if the ID changed.
2019 		 */
2020 		if (old_id != mpc_ioapic_id(apic_id))
2021 			for (i = 0; i < mp_irq_entries; i++)
2022 				if (mp_irqs[i].dstapic == old_id)
2023 					mp_irqs[i].dstapic
2024 						= mpc_ioapic_id(apic_id);
2025 
2026 		/*
2027 		 * Update the ID register according to the right value
2028 		 * from the MPC table if they are different.
2029 		 */
2030 		if (mpc_ioapic_id(apic_id) == reg_00.bits.ID)
2031 			continue;
2032 
2033 		apic_printk(APIC_VERBOSE, KERN_INFO
2034 			"...changing IO-APIC physical APIC ID to %d ...",
2035 			mpc_ioapic_id(apic_id));
2036 
2037 		reg_00.bits.ID = mpc_ioapic_id(apic_id);
2038 		raw_spin_lock_irqsave(&ioapic_lock, flags);
2039 		io_apic_write(apic_id, 0, reg_00.raw);
2040 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2041 
2042 		/*
2043 		 * Sanity check
2044 		 */
2045 		raw_spin_lock_irqsave(&ioapic_lock, flags);
2046 		reg_00.raw = io_apic_read(apic_id, 0);
2047 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2048 		if (reg_00.bits.ID != mpc_ioapic_id(apic_id))
2049 			printk("could not set ID!\n");
2050 		else
2051 			apic_printk(APIC_VERBOSE, " ok.\n");
2052 	}
2053 }
2054 
2055 void __init setup_ioapic_ids_from_mpc(void)
2056 {
2057 
2058 	if (acpi_ioapic)
2059 		return;
2060 	/*
2061 	 * Don't check I/O APIC IDs for xAPIC systems.  They have
2062 	 * no meaning without the serial APIC bus.
2063 	 */
2064 	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
2065 		|| APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
2066 		return;
2067 	setup_ioapic_ids_from_mpc_nocheck();
2068 }
2069 #endif
2070 
2071 int no_timer_check __initdata;
2072 
2073 static int __init notimercheck(char *s)
2074 {
2075 	no_timer_check = 1;
2076 	return 1;
2077 }
2078 __setup("no_timer_check", notimercheck);
2079 
2080 /*
2081  * There is a nasty bug in some older SMP boards, their mptable lies
2082  * about the timer IRQ. We do the following to work around the situation:
2083  *
2084  *	- timer IRQ defaults to IO-APIC IRQ
2085  *	- if this function detects that timer IRQs are defunct, then we fall
2086  *	  back to ISA timer IRQs
2087  */
2088 static int __init timer_irq_works(void)
2089 {
2090 	unsigned long t1 = jiffies;
2091 	unsigned long flags;
2092 
2093 	if (no_timer_check)
2094 		return 1;
2095 
2096 	local_save_flags(flags);
2097 	local_irq_enable();
2098 	/* Let ten ticks pass... */
2099 	mdelay((10 * 1000) / HZ);
2100 	local_irq_restore(flags);
2101 
2102 	/*
2103 	 * Expect a few ticks at least, to be sure some possible
2104 	 * glue logic does not lock up after one or two first
2105 	 * ticks in a non-ExtINT mode.  Also the local APIC
2106 	 * might have cached one ExtINT interrupt.  Finally, at
2107 	 * least one tick may be lost due to delays.
2108 	 */
2109 
2110 	/* jiffies wrap? */
2111 	if (time_after(jiffies, t1 + 4))
2112 		return 1;
2113 	return 0;
2114 }
2115 
2116 /*
2117  * In the SMP+IOAPIC case it might happen that there are an unspecified
2118  * number of pending IRQ events unhandled. These cases are very rare,
2119  * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
2120  * better to do it this way as thus we do not have to be aware of
2121  * 'pending' interrupts in the IRQ path, except at this point.
2122  */
2123 /*
2124  * Edge triggered needs to resend any interrupt
2125  * that was delayed but this is now handled in the device
2126  * independent code.
2127  */
2128 
2129 /*
2130  * Starting up a edge-triggered IO-APIC interrupt is
2131  * nasty - we need to make sure that we get the edge.
2132  * If it is already asserted for some reason, we need
2133  * return 1 to indicate that is was pending.
2134  *
2135  * This is not complete - we should be able to fake
2136  * an edge even if it isn't on the 8259A...
2137  */
2138 
2139 static unsigned int startup_ioapic_irq(struct irq_data *data)
2140 {
2141 	int was_pending = 0, irq = data->irq;
2142 	unsigned long flags;
2143 
2144 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2145 	if (irq < legacy_pic->nr_legacy_irqs) {
2146 		legacy_pic->mask(irq);
2147 		if (legacy_pic->irq_pending(irq))
2148 			was_pending = 1;
2149 	}
2150 	__unmask_ioapic(data->chip_data);
2151 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2152 
2153 	return was_pending;
2154 }
2155 
2156 static int ioapic_retrigger_irq(struct irq_data *data)
2157 {
2158 	struct irq_cfg *cfg = data->chip_data;
2159 	unsigned long flags;
2160 
2161 	raw_spin_lock_irqsave(&vector_lock, flags);
2162 	apic->send_IPI_mask(cpumask_of(cpumask_first(cfg->domain)), cfg->vector);
2163 	raw_spin_unlock_irqrestore(&vector_lock, flags);
2164 
2165 	return 1;
2166 }
2167 
2168 /*
2169  * Level and edge triggered IO-APIC interrupts need different handling,
2170  * so we use two separate IRQ descriptors. Edge triggered IRQs can be
2171  * handled with the level-triggered descriptor, but that one has slightly
2172  * more overhead. Level-triggered interrupts cannot be handled with the
2173  * edge-triggered handler, without risking IRQ storms and other ugly
2174  * races.
2175  */
2176 
2177 #ifdef CONFIG_SMP
2178 void send_cleanup_vector(struct irq_cfg *cfg)
2179 {
2180 	cpumask_var_t cleanup_mask;
2181 
2182 	if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
2183 		unsigned int i;
2184 		for_each_cpu_and(i, cfg->old_domain, cpu_online_mask)
2185 			apic->send_IPI_mask(cpumask_of(i), IRQ_MOVE_CLEANUP_VECTOR);
2186 	} else {
2187 		cpumask_and(cleanup_mask, cfg->old_domain, cpu_online_mask);
2188 		apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
2189 		free_cpumask_var(cleanup_mask);
2190 	}
2191 	cfg->move_in_progress = 0;
2192 }
2193 
2194 static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq_cfg *cfg)
2195 {
2196 	int apic, pin;
2197 	struct irq_pin_list *entry;
2198 	u8 vector = cfg->vector;
2199 
2200 	for_each_irq_pin(entry, cfg->irq_2_pin) {
2201 		unsigned int reg;
2202 
2203 		apic = entry->apic;
2204 		pin = entry->pin;
2205 		/*
2206 		 * With interrupt-remapping, destination information comes
2207 		 * from interrupt-remapping table entry.
2208 		 */
2209 		if (!irq_remapped(cfg))
2210 			io_apic_write(apic, 0x11 + pin*2, dest);
2211 		reg = io_apic_read(apic, 0x10 + pin*2);
2212 		reg &= ~IO_APIC_REDIR_VECTOR_MASK;
2213 		reg |= vector;
2214 		io_apic_modify(apic, 0x10 + pin*2, reg);
2215 	}
2216 }
2217 
2218 /*
2219  * Either sets data->affinity to a valid value, and returns
2220  * ->cpu_mask_to_apicid of that in dest_id, or returns -1 and
2221  * leaves data->affinity untouched.
2222  */
2223 int __ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2224 			  unsigned int *dest_id)
2225 {
2226 	struct irq_cfg *cfg = data->chip_data;
2227 
2228 	if (!cpumask_intersects(mask, cpu_online_mask))
2229 		return -1;
2230 
2231 	if (assign_irq_vector(data->irq, data->chip_data, mask))
2232 		return -1;
2233 
2234 	cpumask_copy(data->affinity, mask);
2235 
2236 	*dest_id = apic->cpu_mask_to_apicid_and(mask, cfg->domain);
2237 	return 0;
2238 }
2239 
2240 static int
2241 ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2242 		    bool force)
2243 {
2244 	unsigned int dest, irq = data->irq;
2245 	unsigned long flags;
2246 	int ret;
2247 
2248 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2249 	ret = __ioapic_set_affinity(data, mask, &dest);
2250 	if (!ret) {
2251 		/* Only the high 8 bits are valid. */
2252 		dest = SET_APIC_LOGICAL_ID(dest);
2253 		__target_IO_APIC_irq(irq, dest, data->chip_data);
2254 	}
2255 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2256 	return ret;
2257 }
2258 
2259 #ifdef CONFIG_INTR_REMAP
2260 
2261 /*
2262  * Migrate the IO-APIC irq in the presence of intr-remapping.
2263  *
2264  * For both level and edge triggered, irq migration is a simple atomic
2265  * update(of vector and cpu destination) of IRTE and flush the hardware cache.
2266  *
2267  * For level triggered, we eliminate the io-apic RTE modification (with the
2268  * updated vector information), by using a virtual vector (io-apic pin number).
2269  * Real vector that is used for interrupting cpu will be coming from
2270  * the interrupt-remapping table entry.
2271  */
2272 static int
2273 ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2274 		       bool force)
2275 {
2276 	struct irq_cfg *cfg = data->chip_data;
2277 	unsigned int dest, irq = data->irq;
2278 	struct irte irte;
2279 
2280 	if (!cpumask_intersects(mask, cpu_online_mask))
2281 		return -EINVAL;
2282 
2283 	if (get_irte(irq, &irte))
2284 		return -EBUSY;
2285 
2286 	if (assign_irq_vector(irq, cfg, mask))
2287 		return -EBUSY;
2288 
2289 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, mask);
2290 
2291 	irte.vector = cfg->vector;
2292 	irte.dest_id = IRTE_DEST(dest);
2293 
2294 	/*
2295 	 * Modified the IRTE and flushes the Interrupt entry cache.
2296 	 */
2297 	modify_irte(irq, &irte);
2298 
2299 	if (cfg->move_in_progress)
2300 		send_cleanup_vector(cfg);
2301 
2302 	cpumask_copy(data->affinity, mask);
2303 	return 0;
2304 }
2305 
2306 #else
2307 static inline int
2308 ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
2309 		       bool force)
2310 {
2311 	return 0;
2312 }
2313 #endif
2314 
2315 asmlinkage void smp_irq_move_cleanup_interrupt(void)
2316 {
2317 	unsigned vector, me;
2318 
2319 	ack_APIC_irq();
2320 	exit_idle();
2321 	irq_enter();
2322 
2323 	me = smp_processor_id();
2324 	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
2325 		unsigned int irq;
2326 		unsigned int irr;
2327 		struct irq_desc *desc;
2328 		struct irq_cfg *cfg;
2329 		irq = __this_cpu_read(vector_irq[vector]);
2330 
2331 		if (irq == -1)
2332 			continue;
2333 
2334 		desc = irq_to_desc(irq);
2335 		if (!desc)
2336 			continue;
2337 
2338 		cfg = irq_cfg(irq);
2339 		raw_spin_lock(&desc->lock);
2340 
2341 		/*
2342 		 * Check if the irq migration is in progress. If so, we
2343 		 * haven't received the cleanup request yet for this irq.
2344 		 */
2345 		if (cfg->move_in_progress)
2346 			goto unlock;
2347 
2348 		if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain))
2349 			goto unlock;
2350 
2351 		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
2352 		/*
2353 		 * Check if the vector that needs to be cleanedup is
2354 		 * registered at the cpu's IRR. If so, then this is not
2355 		 * the best time to clean it up. Lets clean it up in the
2356 		 * next attempt by sending another IRQ_MOVE_CLEANUP_VECTOR
2357 		 * to myself.
2358 		 */
2359 		if (irr  & (1 << (vector % 32))) {
2360 			apic->send_IPI_self(IRQ_MOVE_CLEANUP_VECTOR);
2361 			goto unlock;
2362 		}
2363 		__this_cpu_write(vector_irq[vector], -1);
2364 unlock:
2365 		raw_spin_unlock(&desc->lock);
2366 	}
2367 
2368 	irq_exit();
2369 }
2370 
2371 static void __irq_complete_move(struct irq_cfg *cfg, unsigned vector)
2372 {
2373 	unsigned me;
2374 
2375 	if (likely(!cfg->move_in_progress))
2376 		return;
2377 
2378 	me = smp_processor_id();
2379 
2380 	if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain))
2381 		send_cleanup_vector(cfg);
2382 }
2383 
2384 static void irq_complete_move(struct irq_cfg *cfg)
2385 {
2386 	__irq_complete_move(cfg, ~get_irq_regs()->orig_ax);
2387 }
2388 
2389 void irq_force_complete_move(int irq)
2390 {
2391 	struct irq_cfg *cfg = irq_get_chip_data(irq);
2392 
2393 	if (!cfg)
2394 		return;
2395 
2396 	__irq_complete_move(cfg, cfg->vector);
2397 }
2398 #else
2399 static inline void irq_complete_move(struct irq_cfg *cfg) { }
2400 #endif
2401 
2402 static void ack_apic_edge(struct irq_data *data)
2403 {
2404 	irq_complete_move(data->chip_data);
2405 	irq_move_irq(data);
2406 	ack_APIC_irq();
2407 }
2408 
2409 atomic_t irq_mis_count;
2410 
2411 /*
2412  * IO-APIC versions below 0x20 don't support EOI register.
2413  * For the record, here is the information about various versions:
2414  *     0Xh     82489DX
2415  *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
2416  *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
2417  *     30h-FFh Reserved
2418  *
2419  * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
2420  * version as 0x2. This is an error with documentation and these ICH chips
2421  * use io-apic's of version 0x20.
2422  *
2423  * For IO-APIC's with EOI register, we use that to do an explicit EOI.
2424  * Otherwise, we simulate the EOI message manually by changing the trigger
2425  * mode to edge and then back to level, with RTE being masked during this.
2426 */
2427 static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
2428 {
2429 	struct irq_pin_list *entry;
2430 	unsigned long flags;
2431 
2432 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2433 	for_each_irq_pin(entry, cfg->irq_2_pin) {
2434 		if (mpc_ioapic_ver(entry->apic) >= 0x20) {
2435 			/*
2436 			 * Intr-remapping uses pin number as the virtual vector
2437 			 * in the RTE. Actual vector is programmed in
2438 			 * intr-remapping table entry. Hence for the io-apic
2439 			 * EOI we use the pin number.
2440 			 */
2441 			if (irq_remapped(cfg))
2442 				io_apic_eoi(entry->apic, entry->pin);
2443 			else
2444 				io_apic_eoi(entry->apic, cfg->vector);
2445 		} else {
2446 			__mask_and_edge_IO_APIC_irq(entry);
2447 			__unmask_and_level_IO_APIC_irq(entry);
2448 		}
2449 	}
2450 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2451 }
2452 
2453 static void ack_apic_level(struct irq_data *data)
2454 {
2455 	struct irq_cfg *cfg = data->chip_data;
2456 	int i, do_unmask_irq = 0, irq = data->irq;
2457 	unsigned long v;
2458 
2459 	irq_complete_move(cfg);
2460 #ifdef CONFIG_GENERIC_PENDING_IRQ
2461 	/* If we are moving the irq we need to mask it */
2462 	if (unlikely(irqd_is_setaffinity_pending(data))) {
2463 		do_unmask_irq = 1;
2464 		mask_ioapic(cfg);
2465 	}
2466 #endif
2467 
2468 	/*
2469 	 * It appears there is an erratum which affects at least version 0x11
2470 	 * of I/O APIC (that's the 82093AA and cores integrated into various
2471 	 * chipsets).  Under certain conditions a level-triggered interrupt is
2472 	 * erroneously delivered as edge-triggered one but the respective IRR
2473 	 * bit gets set nevertheless.  As a result the I/O unit expects an EOI
2474 	 * message but it will never arrive and further interrupts are blocked
2475 	 * from the source.  The exact reason is so far unknown, but the
2476 	 * phenomenon was observed when two consecutive interrupt requests
2477 	 * from a given source get delivered to the same CPU and the source is
2478 	 * temporarily disabled in between.
2479 	 *
2480 	 * A workaround is to simulate an EOI message manually.  We achieve it
2481 	 * by setting the trigger mode to edge and then to level when the edge
2482 	 * trigger mode gets detected in the TMR of a local APIC for a
2483 	 * level-triggered interrupt.  We mask the source for the time of the
2484 	 * operation to prevent an edge-triggered interrupt escaping meanwhile.
2485 	 * The idea is from Manfred Spraul.  --macro
2486 	 *
2487 	 * Also in the case when cpu goes offline, fixup_irqs() will forward
2488 	 * any unhandled interrupt on the offlined cpu to the new cpu
2489 	 * destination that is handling the corresponding interrupt. This
2490 	 * interrupt forwarding is done via IPI's. Hence, in this case also
2491 	 * level-triggered io-apic interrupt will be seen as an edge
2492 	 * interrupt in the IRR. And we can't rely on the cpu's EOI
2493 	 * to be broadcasted to the IO-APIC's which will clear the remoteIRR
2494 	 * corresponding to the level-triggered interrupt. Hence on IO-APIC's
2495 	 * supporting EOI register, we do an explicit EOI to clear the
2496 	 * remote IRR and on IO-APIC's which don't have an EOI register,
2497 	 * we use the above logic (mask+edge followed by unmask+level) from
2498 	 * Manfred Spraul to clear the remote IRR.
2499 	 */
2500 	i = cfg->vector;
2501 	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
2502 
2503 	/*
2504 	 * We must acknowledge the irq before we move it or the acknowledge will
2505 	 * not propagate properly.
2506 	 */
2507 	ack_APIC_irq();
2508 
2509 	/*
2510 	 * Tail end of clearing remote IRR bit (either by delivering the EOI
2511 	 * message via io-apic EOI register write or simulating it using
2512 	 * mask+edge followed by unnask+level logic) manually when the
2513 	 * level triggered interrupt is seen as the edge triggered interrupt
2514 	 * at the cpu.
2515 	 */
2516 	if (!(v & (1 << (i & 0x1f)))) {
2517 		atomic_inc(&irq_mis_count);
2518 
2519 		eoi_ioapic_irq(irq, cfg);
2520 	}
2521 
2522 	/* Now we can move and renable the irq */
2523 	if (unlikely(do_unmask_irq)) {
2524 		/* Only migrate the irq if the ack has been received.
2525 		 *
2526 		 * On rare occasions the broadcast level triggered ack gets
2527 		 * delayed going to ioapics, and if we reprogram the
2528 		 * vector while Remote IRR is still set the irq will never
2529 		 * fire again.
2530 		 *
2531 		 * To prevent this scenario we read the Remote IRR bit
2532 		 * of the ioapic.  This has two effects.
2533 		 * - On any sane system the read of the ioapic will
2534 		 *   flush writes (and acks) going to the ioapic from
2535 		 *   this cpu.
2536 		 * - We get to see if the ACK has actually been delivered.
2537 		 *
2538 		 * Based on failed experiments of reprogramming the
2539 		 * ioapic entry from outside of irq context starting
2540 		 * with masking the ioapic entry and then polling until
2541 		 * Remote IRR was clear before reprogramming the
2542 		 * ioapic I don't trust the Remote IRR bit to be
2543 		 * completey accurate.
2544 		 *
2545 		 * However there appears to be no other way to plug
2546 		 * this race, so if the Remote IRR bit is not
2547 		 * accurate and is causing problems then it is a hardware bug
2548 		 * and you can go talk to the chipset vendor about it.
2549 		 */
2550 		if (!io_apic_level_ack_pending(cfg))
2551 			irq_move_masked_irq(data);
2552 		unmask_ioapic(cfg);
2553 	}
2554 }
2555 
2556 #ifdef CONFIG_INTR_REMAP
2557 static void ir_ack_apic_edge(struct irq_data *data)
2558 {
2559 	ack_APIC_irq();
2560 }
2561 
2562 static void ir_ack_apic_level(struct irq_data *data)
2563 {
2564 	ack_APIC_irq();
2565 	eoi_ioapic_irq(data->irq, data->chip_data);
2566 }
2567 #endif /* CONFIG_INTR_REMAP */
2568 
2569 static struct irq_chip ioapic_chip __read_mostly = {
2570 	.name			= "IO-APIC",
2571 	.irq_startup		= startup_ioapic_irq,
2572 	.irq_mask		= mask_ioapic_irq,
2573 	.irq_unmask		= unmask_ioapic_irq,
2574 	.irq_ack		= ack_apic_edge,
2575 	.irq_eoi		= ack_apic_level,
2576 #ifdef CONFIG_SMP
2577 	.irq_set_affinity	= ioapic_set_affinity,
2578 #endif
2579 	.irq_retrigger		= ioapic_retrigger_irq,
2580 };
2581 
2582 static struct irq_chip ir_ioapic_chip __read_mostly = {
2583 	.name			= "IR-IO-APIC",
2584 	.irq_startup		= startup_ioapic_irq,
2585 	.irq_mask		= mask_ioapic_irq,
2586 	.irq_unmask		= unmask_ioapic_irq,
2587 #ifdef CONFIG_INTR_REMAP
2588 	.irq_ack		= ir_ack_apic_edge,
2589 	.irq_eoi		= ir_ack_apic_level,
2590 #ifdef CONFIG_SMP
2591 	.irq_set_affinity	= ir_ioapic_set_affinity,
2592 #endif
2593 #endif
2594 	.irq_retrigger		= ioapic_retrigger_irq,
2595 };
2596 
2597 static inline void init_IO_APIC_traps(void)
2598 {
2599 	struct irq_cfg *cfg;
2600 	unsigned int irq;
2601 
2602 	/*
2603 	 * NOTE! The local APIC isn't very good at handling
2604 	 * multiple interrupts at the same interrupt level.
2605 	 * As the interrupt level is determined by taking the
2606 	 * vector number and shifting that right by 4, we
2607 	 * want to spread these out a bit so that they don't
2608 	 * all fall in the same interrupt level.
2609 	 *
2610 	 * Also, we've got to be careful not to trash gate
2611 	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
2612 	 */
2613 	for_each_active_irq(irq) {
2614 		cfg = irq_get_chip_data(irq);
2615 		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
2616 			/*
2617 			 * Hmm.. We don't have an entry for this,
2618 			 * so default to an old-fashioned 8259
2619 			 * interrupt if we can..
2620 			 */
2621 			if (irq < legacy_pic->nr_legacy_irqs)
2622 				legacy_pic->make_irq(irq);
2623 			else
2624 				/* Strange. Oh, well.. */
2625 				irq_set_chip(irq, &no_irq_chip);
2626 		}
2627 	}
2628 }
2629 
2630 /*
2631  * The local APIC irq-chip implementation:
2632  */
2633 
2634 static void mask_lapic_irq(struct irq_data *data)
2635 {
2636 	unsigned long v;
2637 
2638 	v = apic_read(APIC_LVT0);
2639 	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
2640 }
2641 
2642 static void unmask_lapic_irq(struct irq_data *data)
2643 {
2644 	unsigned long v;
2645 
2646 	v = apic_read(APIC_LVT0);
2647 	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
2648 }
2649 
2650 static void ack_lapic_irq(struct irq_data *data)
2651 {
2652 	ack_APIC_irq();
2653 }
2654 
2655 static struct irq_chip lapic_chip __read_mostly = {
2656 	.name		= "local-APIC",
2657 	.irq_mask	= mask_lapic_irq,
2658 	.irq_unmask	= unmask_lapic_irq,
2659 	.irq_ack	= ack_lapic_irq,
2660 };
2661 
2662 static void lapic_register_intr(int irq)
2663 {
2664 	irq_clear_status_flags(irq, IRQ_LEVEL);
2665 	irq_set_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
2666 				      "edge");
2667 }
2668 
2669 /*
2670  * This looks a bit hackish but it's about the only one way of sending
2671  * a few INTA cycles to 8259As and any associated glue logic.  ICR does
2672  * not support the ExtINT mode, unfortunately.  We need to send these
2673  * cycles as some i82489DX-based boards have glue logic that keeps the
2674  * 8259A interrupt line asserted until INTA.  --macro
2675  */
2676 static inline void __init unlock_ExtINT_logic(void)
2677 {
2678 	int apic, pin, i;
2679 	struct IO_APIC_route_entry entry0, entry1;
2680 	unsigned char save_control, save_freq_select;
2681 
2682 	pin  = find_isa_irq_pin(8, mp_INT);
2683 	if (pin == -1) {
2684 		WARN_ON_ONCE(1);
2685 		return;
2686 	}
2687 	apic = find_isa_irq_apic(8, mp_INT);
2688 	if (apic == -1) {
2689 		WARN_ON_ONCE(1);
2690 		return;
2691 	}
2692 
2693 	entry0 = ioapic_read_entry(apic, pin);
2694 	clear_IO_APIC_pin(apic, pin);
2695 
2696 	memset(&entry1, 0, sizeof(entry1));
2697 
2698 	entry1.dest_mode = 0;			/* physical delivery */
2699 	entry1.mask = 0;			/* unmask IRQ now */
2700 	entry1.dest = hard_smp_processor_id();
2701 	entry1.delivery_mode = dest_ExtINT;
2702 	entry1.polarity = entry0.polarity;
2703 	entry1.trigger = 0;
2704 	entry1.vector = 0;
2705 
2706 	ioapic_write_entry(apic, pin, entry1);
2707 
2708 	save_control = CMOS_READ(RTC_CONTROL);
2709 	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
2710 	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
2711 		   RTC_FREQ_SELECT);
2712 	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
2713 
2714 	i = 100;
2715 	while (i-- > 0) {
2716 		mdelay(10);
2717 		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
2718 			i -= 10;
2719 	}
2720 
2721 	CMOS_WRITE(save_control, RTC_CONTROL);
2722 	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
2723 	clear_IO_APIC_pin(apic, pin);
2724 
2725 	ioapic_write_entry(apic, pin, entry0);
2726 }
2727 
2728 static int disable_timer_pin_1 __initdata;
2729 /* Actually the next is obsolete, but keep it for paranoid reasons -AK */
2730 static int __init disable_timer_pin_setup(char *arg)
2731 {
2732 	disable_timer_pin_1 = 1;
2733 	return 0;
2734 }
2735 early_param("disable_timer_pin_1", disable_timer_pin_setup);
2736 
2737 int timer_through_8259 __initdata;
2738 
2739 /*
2740  * This code may look a bit paranoid, but it's supposed to cooperate with
2741  * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
2742  * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
2743  * fanatically on his truly buggy board.
2744  *
2745  * FIXME: really need to revamp this for all platforms.
2746  */
2747 static inline void __init check_timer(void)
2748 {
2749 	struct irq_cfg *cfg = irq_get_chip_data(0);
2750 	int node = cpu_to_node(0);
2751 	int apic1, pin1, apic2, pin2;
2752 	unsigned long flags;
2753 	int no_pin1 = 0;
2754 
2755 	local_irq_save(flags);
2756 
2757 	/*
2758 	 * get/set the timer IRQ vector:
2759 	 */
2760 	legacy_pic->mask(0);
2761 	assign_irq_vector(0, cfg, apic->target_cpus());
2762 
2763 	/*
2764 	 * As IRQ0 is to be enabled in the 8259A, the virtual
2765 	 * wire has to be disabled in the local APIC.  Also
2766 	 * timer interrupts need to be acknowledged manually in
2767 	 * the 8259A for the i82489DX when using the NMI
2768 	 * watchdog as that APIC treats NMIs as level-triggered.
2769 	 * The AEOI mode will finish them in the 8259A
2770 	 * automatically.
2771 	 */
2772 	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
2773 	legacy_pic->init(1);
2774 
2775 	pin1  = find_isa_irq_pin(0, mp_INT);
2776 	apic1 = find_isa_irq_apic(0, mp_INT);
2777 	pin2  = ioapic_i8259.pin;
2778 	apic2 = ioapic_i8259.apic;
2779 
2780 	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
2781 		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
2782 		    cfg->vector, apic1, pin1, apic2, pin2);
2783 
2784 	/*
2785 	 * Some BIOS writers are clueless and report the ExtINTA
2786 	 * I/O APIC input from the cascaded 8259A as the timer
2787 	 * interrupt input.  So just in case, if only one pin
2788 	 * was found above, try it both directly and through the
2789 	 * 8259A.
2790 	 */
2791 	if (pin1 == -1) {
2792 		if (intr_remapping_enabled)
2793 			panic("BIOS bug: timer not connected to IO-APIC");
2794 		pin1 = pin2;
2795 		apic1 = apic2;
2796 		no_pin1 = 1;
2797 	} else if (pin2 == -1) {
2798 		pin2 = pin1;
2799 		apic2 = apic1;
2800 	}
2801 
2802 	if (pin1 != -1) {
2803 		/*
2804 		 * Ok, does IRQ0 through the IOAPIC work?
2805 		 */
2806 		if (no_pin1) {
2807 			add_pin_to_irq_node(cfg, node, apic1, pin1);
2808 			setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
2809 		} else {
2810 			/* for edge trigger, setup_ioapic_irq already
2811 			 * leave it unmasked.
2812 			 * so only need to unmask if it is level-trigger
2813 			 * do we really have level trigger timer?
2814 			 */
2815 			int idx;
2816 			idx = find_irq_entry(apic1, pin1, mp_INT);
2817 			if (idx != -1 && irq_trigger(idx))
2818 				unmask_ioapic(cfg);
2819 		}
2820 		if (timer_irq_works()) {
2821 			if (disable_timer_pin_1 > 0)
2822 				clear_IO_APIC_pin(0, pin1);
2823 			goto out;
2824 		}
2825 		if (intr_remapping_enabled)
2826 			panic("timer doesn't work through Interrupt-remapped IO-APIC");
2827 		local_irq_disable();
2828 		clear_IO_APIC_pin(apic1, pin1);
2829 		if (!no_pin1)
2830 			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
2831 				    "8254 timer not connected to IO-APIC\n");
2832 
2833 		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
2834 			    "(IRQ0) through the 8259A ...\n");
2835 		apic_printk(APIC_QUIET, KERN_INFO
2836 			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
2837 		/*
2838 		 * legacy devices should be connected to IO APIC #0
2839 		 */
2840 		replace_pin_at_irq_node(cfg, node, apic1, pin1, apic2, pin2);
2841 		setup_timer_IRQ0_pin(apic2, pin2, cfg->vector);
2842 		legacy_pic->unmask(0);
2843 		if (timer_irq_works()) {
2844 			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
2845 			timer_through_8259 = 1;
2846 			goto out;
2847 		}
2848 		/*
2849 		 * Cleanup, just in case ...
2850 		 */
2851 		local_irq_disable();
2852 		legacy_pic->mask(0);
2853 		clear_IO_APIC_pin(apic2, pin2);
2854 		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
2855 	}
2856 
2857 	apic_printk(APIC_QUIET, KERN_INFO
2858 		    "...trying to set up timer as Virtual Wire IRQ...\n");
2859 
2860 	lapic_register_intr(0);
2861 	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
2862 	legacy_pic->unmask(0);
2863 
2864 	if (timer_irq_works()) {
2865 		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2866 		goto out;
2867 	}
2868 	local_irq_disable();
2869 	legacy_pic->mask(0);
2870 	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
2871 	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
2872 
2873 	apic_printk(APIC_QUIET, KERN_INFO
2874 		    "...trying to set up timer as ExtINT IRQ...\n");
2875 
2876 	legacy_pic->init(0);
2877 	legacy_pic->make_irq(0);
2878 	apic_write(APIC_LVT0, APIC_DM_EXTINT);
2879 
2880 	unlock_ExtINT_logic();
2881 
2882 	if (timer_irq_works()) {
2883 		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
2884 		goto out;
2885 	}
2886 	local_irq_disable();
2887 	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
2888 	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
2889 		"report.  Then try booting with the 'noapic' option.\n");
2890 out:
2891 	local_irq_restore(flags);
2892 }
2893 
2894 /*
2895  * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
2896  * to devices.  However there may be an I/O APIC pin available for
2897  * this interrupt regardless.  The pin may be left unconnected, but
2898  * typically it will be reused as an ExtINT cascade interrupt for
2899  * the master 8259A.  In the MPS case such a pin will normally be
2900  * reported as an ExtINT interrupt in the MP table.  With ACPI
2901  * there is no provision for ExtINT interrupts, and in the absence
2902  * of an override it would be treated as an ordinary ISA I/O APIC
2903  * interrupt, that is edge-triggered and unmasked by default.  We
2904  * used to do this, but it caused problems on some systems because
2905  * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
2906  * the same ExtINT cascade interrupt to drive the local APIC of the
2907  * bootstrap processor.  Therefore we refrain from routing IRQ2 to
2908  * the I/O APIC in all cases now.  No actual device should request
2909  * it anyway.  --macro
2910  */
2911 #define PIC_IRQS	(1UL << PIC_CASCADE_IR)
2912 
2913 void __init setup_IO_APIC(void)
2914 {
2915 
2916 	/*
2917 	 * calling enable_IO_APIC() is moved to setup_local_APIC for BP
2918 	 */
2919 	io_apic_irqs = legacy_pic->nr_legacy_irqs ? ~PIC_IRQS : ~0UL;
2920 
2921 	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
2922 	/*
2923          * Set up IO-APIC IRQ routing.
2924          */
2925 	x86_init.mpparse.setup_ioapic_ids();
2926 
2927 	sync_Arb_IDs();
2928 	setup_IO_APIC_irqs();
2929 	init_IO_APIC_traps();
2930 	if (legacy_pic->nr_legacy_irqs)
2931 		check_timer();
2932 }
2933 
2934 /*
2935  *      Called after all the initialization is done. If we didn't find any
2936  *      APIC bugs then we can allow the modify fast path
2937  */
2938 
2939 static int __init io_apic_bug_finalize(void)
2940 {
2941 	if (sis_apic_bug == -1)
2942 		sis_apic_bug = 0;
2943 	return 0;
2944 }
2945 
2946 late_initcall(io_apic_bug_finalize);
2947 
2948 static void resume_ioapic_id(int ioapic_id)
2949 {
2950 	unsigned long flags;
2951 	union IO_APIC_reg_00 reg_00;
2952 
2953 
2954 	raw_spin_lock_irqsave(&ioapic_lock, flags);
2955 	reg_00.raw = io_apic_read(ioapic_id, 0);
2956 	if (reg_00.bits.ID != mpc_ioapic_id(ioapic_id)) {
2957 		reg_00.bits.ID = mpc_ioapic_id(ioapic_id);
2958 		io_apic_write(ioapic_id, 0, reg_00.raw);
2959 	}
2960 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
2961 }
2962 
2963 static void ioapic_resume(void)
2964 {
2965 	int ioapic_id;
2966 
2967 	for (ioapic_id = nr_ioapics - 1; ioapic_id >= 0; ioapic_id--)
2968 		resume_ioapic_id(ioapic_id);
2969 
2970 	restore_ioapic_entries();
2971 }
2972 
2973 static struct syscore_ops ioapic_syscore_ops = {
2974 	.suspend = save_ioapic_entries,
2975 	.resume = ioapic_resume,
2976 };
2977 
2978 static int __init ioapic_init_ops(void)
2979 {
2980 	register_syscore_ops(&ioapic_syscore_ops);
2981 
2982 	return 0;
2983 }
2984 
2985 device_initcall(ioapic_init_ops);
2986 
2987 /*
2988  * Dynamic irq allocate and deallocation
2989  */
2990 unsigned int create_irq_nr(unsigned int from, int node)
2991 {
2992 	struct irq_cfg *cfg;
2993 	unsigned long flags;
2994 	unsigned int ret = 0;
2995 	int irq;
2996 
2997 	if (from < nr_irqs_gsi)
2998 		from = nr_irqs_gsi;
2999 
3000 	irq = alloc_irq_from(from, node);
3001 	if (irq < 0)
3002 		return 0;
3003 	cfg = alloc_irq_cfg(irq, node);
3004 	if (!cfg) {
3005 		free_irq_at(irq, NULL);
3006 		return 0;
3007 	}
3008 
3009 	raw_spin_lock_irqsave(&vector_lock, flags);
3010 	if (!__assign_irq_vector(irq, cfg, apic->target_cpus()))
3011 		ret = irq;
3012 	raw_spin_unlock_irqrestore(&vector_lock, flags);
3013 
3014 	if (ret) {
3015 		irq_set_chip_data(irq, cfg);
3016 		irq_clear_status_flags(irq, IRQ_NOREQUEST);
3017 	} else {
3018 		free_irq_at(irq, cfg);
3019 	}
3020 	return ret;
3021 }
3022 
3023 int create_irq(void)
3024 {
3025 	int node = cpu_to_node(0);
3026 	unsigned int irq_want;
3027 	int irq;
3028 
3029 	irq_want = nr_irqs_gsi;
3030 	irq = create_irq_nr(irq_want, node);
3031 
3032 	if (irq == 0)
3033 		irq = -1;
3034 
3035 	return irq;
3036 }
3037 
3038 void destroy_irq(unsigned int irq)
3039 {
3040 	struct irq_cfg *cfg = irq_get_chip_data(irq);
3041 	unsigned long flags;
3042 
3043 	irq_set_status_flags(irq, IRQ_NOREQUEST|IRQ_NOPROBE);
3044 
3045 	if (irq_remapped(cfg))
3046 		free_irte(irq);
3047 	raw_spin_lock_irqsave(&vector_lock, flags);
3048 	__clear_irq_vector(irq, cfg);
3049 	raw_spin_unlock_irqrestore(&vector_lock, flags);
3050 	free_irq_at(irq, cfg);
3051 }
3052 
3053 /*
3054  * MSI message composition
3055  */
3056 #ifdef CONFIG_PCI_MSI
3057 static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
3058 			   struct msi_msg *msg, u8 hpet_id)
3059 {
3060 	struct irq_cfg *cfg;
3061 	int err;
3062 	unsigned dest;
3063 
3064 	if (disable_apic)
3065 		return -ENXIO;
3066 
3067 	cfg = irq_cfg(irq);
3068 	err = assign_irq_vector(irq, cfg, apic->target_cpus());
3069 	if (err)
3070 		return err;
3071 
3072 	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
3073 
3074 	if (irq_remapped(cfg)) {
3075 		struct irte irte;
3076 		int ir_index;
3077 		u16 sub_handle;
3078 
3079 		ir_index = map_irq_to_irte_handle(irq, &sub_handle);
3080 		BUG_ON(ir_index == -1);
3081 
3082 		prepare_irte(&irte, cfg->vector, dest);
3083 
3084 		/* Set source-id of interrupt request */
3085 		if (pdev)
3086 			set_msi_sid(&irte, pdev);
3087 		else
3088 			set_hpet_sid(&irte, hpet_id);
3089 
3090 		modify_irte(irq, &irte);
3091 
3092 		msg->address_hi = MSI_ADDR_BASE_HI;
3093 		msg->data = sub_handle;
3094 		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
3095 				  MSI_ADDR_IR_SHV |
3096 				  MSI_ADDR_IR_INDEX1(ir_index) |
3097 				  MSI_ADDR_IR_INDEX2(ir_index);
3098 	} else {
3099 		if (x2apic_enabled())
3100 			msg->address_hi = MSI_ADDR_BASE_HI |
3101 					  MSI_ADDR_EXT_DEST_ID(dest);
3102 		else
3103 			msg->address_hi = MSI_ADDR_BASE_HI;
3104 
3105 		msg->address_lo =
3106 			MSI_ADDR_BASE_LO |
3107 			((apic->irq_dest_mode == 0) ?
3108 				MSI_ADDR_DEST_MODE_PHYSICAL:
3109 				MSI_ADDR_DEST_MODE_LOGICAL) |
3110 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3111 				MSI_ADDR_REDIRECTION_CPU:
3112 				MSI_ADDR_REDIRECTION_LOWPRI) |
3113 			MSI_ADDR_DEST_ID(dest);
3114 
3115 		msg->data =
3116 			MSI_DATA_TRIGGER_EDGE |
3117 			MSI_DATA_LEVEL_ASSERT |
3118 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3119 				MSI_DATA_DELIVERY_FIXED:
3120 				MSI_DATA_DELIVERY_LOWPRI) |
3121 			MSI_DATA_VECTOR(cfg->vector);
3122 	}
3123 	return err;
3124 }
3125 
3126 #ifdef CONFIG_SMP
3127 static int
3128 msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
3129 {
3130 	struct irq_cfg *cfg = data->chip_data;
3131 	struct msi_msg msg;
3132 	unsigned int dest;
3133 
3134 	if (__ioapic_set_affinity(data, mask, &dest))
3135 		return -1;
3136 
3137 	__get_cached_msi_msg(data->msi_desc, &msg);
3138 
3139 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3140 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3141 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3142 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3143 
3144 	__write_msi_msg(data->msi_desc, &msg);
3145 
3146 	return 0;
3147 }
3148 #ifdef CONFIG_INTR_REMAP
3149 /*
3150  * Migrate the MSI irq to another cpumask. This migration is
3151  * done in the process context using interrupt-remapping hardware.
3152  */
3153 static int
3154 ir_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
3155 		    bool force)
3156 {
3157 	struct irq_cfg *cfg = data->chip_data;
3158 	unsigned int dest, irq = data->irq;
3159 	struct irte irte;
3160 
3161 	if (get_irte(irq, &irte))
3162 		return -1;
3163 
3164 	if (__ioapic_set_affinity(data, mask, &dest))
3165 		return -1;
3166 
3167 	irte.vector = cfg->vector;
3168 	irte.dest_id = IRTE_DEST(dest);
3169 
3170 	/*
3171 	 * atomically update the IRTE with the new destination and vector.
3172 	 */
3173 	modify_irte(irq, &irte);
3174 
3175 	/*
3176 	 * After this point, all the interrupts will start arriving
3177 	 * at the new destination. So, time to cleanup the previous
3178 	 * vector allocation.
3179 	 */
3180 	if (cfg->move_in_progress)
3181 		send_cleanup_vector(cfg);
3182 
3183 	return 0;
3184 }
3185 
3186 #endif
3187 #endif /* CONFIG_SMP */
3188 
3189 /*
3190  * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
3191  * which implement the MSI or MSI-X Capability Structure.
3192  */
3193 static struct irq_chip msi_chip = {
3194 	.name			= "PCI-MSI",
3195 	.irq_unmask		= unmask_msi_irq,
3196 	.irq_mask		= mask_msi_irq,
3197 	.irq_ack		= ack_apic_edge,
3198 #ifdef CONFIG_SMP
3199 	.irq_set_affinity	= msi_set_affinity,
3200 #endif
3201 	.irq_retrigger		= ioapic_retrigger_irq,
3202 };
3203 
3204 static struct irq_chip msi_ir_chip = {
3205 	.name			= "IR-PCI-MSI",
3206 	.irq_unmask		= unmask_msi_irq,
3207 	.irq_mask		= mask_msi_irq,
3208 #ifdef CONFIG_INTR_REMAP
3209 	.irq_ack		= ir_ack_apic_edge,
3210 #ifdef CONFIG_SMP
3211 	.irq_set_affinity	= ir_msi_set_affinity,
3212 #endif
3213 #endif
3214 	.irq_retrigger		= ioapic_retrigger_irq,
3215 };
3216 
3217 /*
3218  * Map the PCI dev to the corresponding remapping hardware unit
3219  * and allocate 'nvec' consecutive interrupt-remapping table entries
3220  * in it.
3221  */
3222 static int msi_alloc_irte(struct pci_dev *dev, int irq, int nvec)
3223 {
3224 	struct intel_iommu *iommu;
3225 	int index;
3226 
3227 	iommu = map_dev_to_ir(dev);
3228 	if (!iommu) {
3229 		printk(KERN_ERR
3230 		       "Unable to map PCI %s to iommu\n", pci_name(dev));
3231 		return -ENOENT;
3232 	}
3233 
3234 	index = alloc_irte(iommu, irq, nvec);
3235 	if (index < 0) {
3236 		printk(KERN_ERR
3237 		       "Unable to allocate %d IRTE for PCI %s\n", nvec,
3238 		       pci_name(dev));
3239 		return -ENOSPC;
3240 	}
3241 	return index;
3242 }
3243 
3244 static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int irq)
3245 {
3246 	struct irq_chip *chip = &msi_chip;
3247 	struct msi_msg msg;
3248 	int ret;
3249 
3250 	ret = msi_compose_msg(dev, irq, &msg, -1);
3251 	if (ret < 0)
3252 		return ret;
3253 
3254 	irq_set_msi_desc(irq, msidesc);
3255 	write_msi_msg(irq, &msg);
3256 
3257 	if (irq_remapped(irq_get_chip_data(irq))) {
3258 		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
3259 		chip = &msi_ir_chip;
3260 	}
3261 
3262 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
3263 
3264 	dev_printk(KERN_DEBUG, &dev->dev, "irq %d for MSI/MSI-X\n", irq);
3265 
3266 	return 0;
3267 }
3268 
3269 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
3270 {
3271 	int node, ret, sub_handle, index = 0;
3272 	unsigned int irq, irq_want;
3273 	struct msi_desc *msidesc;
3274 	struct intel_iommu *iommu = NULL;
3275 
3276 	/* x86 doesn't support multiple MSI yet */
3277 	if (type == PCI_CAP_ID_MSI && nvec > 1)
3278 		return 1;
3279 
3280 	node = dev_to_node(&dev->dev);
3281 	irq_want = nr_irqs_gsi;
3282 	sub_handle = 0;
3283 	list_for_each_entry(msidesc, &dev->msi_list, list) {
3284 		irq = create_irq_nr(irq_want, node);
3285 		if (irq == 0)
3286 			return -1;
3287 		irq_want = irq + 1;
3288 		if (!intr_remapping_enabled)
3289 			goto no_ir;
3290 
3291 		if (!sub_handle) {
3292 			/*
3293 			 * allocate the consecutive block of IRTE's
3294 			 * for 'nvec'
3295 			 */
3296 			index = msi_alloc_irte(dev, irq, nvec);
3297 			if (index < 0) {
3298 				ret = index;
3299 				goto error;
3300 			}
3301 		} else {
3302 			iommu = map_dev_to_ir(dev);
3303 			if (!iommu) {
3304 				ret = -ENOENT;
3305 				goto error;
3306 			}
3307 			/*
3308 			 * setup the mapping between the irq and the IRTE
3309 			 * base index, the sub_handle pointing to the
3310 			 * appropriate interrupt remap table entry.
3311 			 */
3312 			set_irte_irq(irq, iommu, index, sub_handle);
3313 		}
3314 no_ir:
3315 		ret = setup_msi_irq(dev, msidesc, irq);
3316 		if (ret < 0)
3317 			goto error;
3318 		sub_handle++;
3319 	}
3320 	return 0;
3321 
3322 error:
3323 	destroy_irq(irq);
3324 	return ret;
3325 }
3326 
3327 void native_teardown_msi_irq(unsigned int irq)
3328 {
3329 	destroy_irq(irq);
3330 }
3331 
3332 #if defined (CONFIG_DMAR) || defined (CONFIG_INTR_REMAP)
3333 #ifdef CONFIG_SMP
3334 static int
3335 dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
3336 		      bool force)
3337 {
3338 	struct irq_cfg *cfg = data->chip_data;
3339 	unsigned int dest, irq = data->irq;
3340 	struct msi_msg msg;
3341 
3342 	if (__ioapic_set_affinity(data, mask, &dest))
3343 		return -1;
3344 
3345 	dmar_msi_read(irq, &msg);
3346 
3347 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3348 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3349 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3350 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3351 	msg.address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(dest);
3352 
3353 	dmar_msi_write(irq, &msg);
3354 
3355 	return 0;
3356 }
3357 
3358 #endif /* CONFIG_SMP */
3359 
3360 static struct irq_chip dmar_msi_type = {
3361 	.name			= "DMAR_MSI",
3362 	.irq_unmask		= dmar_msi_unmask,
3363 	.irq_mask		= dmar_msi_mask,
3364 	.irq_ack		= ack_apic_edge,
3365 #ifdef CONFIG_SMP
3366 	.irq_set_affinity	= dmar_msi_set_affinity,
3367 #endif
3368 	.irq_retrigger		= ioapic_retrigger_irq,
3369 };
3370 
3371 int arch_setup_dmar_msi(unsigned int irq)
3372 {
3373 	int ret;
3374 	struct msi_msg msg;
3375 
3376 	ret = msi_compose_msg(NULL, irq, &msg, -1);
3377 	if (ret < 0)
3378 		return ret;
3379 	dmar_msi_write(irq, &msg);
3380 	irq_set_chip_and_handler_name(irq, &dmar_msi_type, handle_edge_irq,
3381 				      "edge");
3382 	return 0;
3383 }
3384 #endif
3385 
3386 #ifdef CONFIG_HPET_TIMER
3387 
3388 #ifdef CONFIG_SMP
3389 static int hpet_msi_set_affinity(struct irq_data *data,
3390 				 const struct cpumask *mask, bool force)
3391 {
3392 	struct irq_cfg *cfg = data->chip_data;
3393 	struct msi_msg msg;
3394 	unsigned int dest;
3395 
3396 	if (__ioapic_set_affinity(data, mask, &dest))
3397 		return -1;
3398 
3399 	hpet_msi_read(data->handler_data, &msg);
3400 
3401 	msg.data &= ~MSI_DATA_VECTOR_MASK;
3402 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
3403 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
3404 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
3405 
3406 	hpet_msi_write(data->handler_data, &msg);
3407 
3408 	return 0;
3409 }
3410 
3411 #endif /* CONFIG_SMP */
3412 
3413 static struct irq_chip ir_hpet_msi_type = {
3414 	.name			= "IR-HPET_MSI",
3415 	.irq_unmask		= hpet_msi_unmask,
3416 	.irq_mask		= hpet_msi_mask,
3417 #ifdef CONFIG_INTR_REMAP
3418 	.irq_ack		= ir_ack_apic_edge,
3419 #ifdef CONFIG_SMP
3420 	.irq_set_affinity	= ir_msi_set_affinity,
3421 #endif
3422 #endif
3423 	.irq_retrigger		= ioapic_retrigger_irq,
3424 };
3425 
3426 static struct irq_chip hpet_msi_type = {
3427 	.name = "HPET_MSI",
3428 	.irq_unmask = hpet_msi_unmask,
3429 	.irq_mask = hpet_msi_mask,
3430 	.irq_ack = ack_apic_edge,
3431 #ifdef CONFIG_SMP
3432 	.irq_set_affinity = hpet_msi_set_affinity,
3433 #endif
3434 	.irq_retrigger = ioapic_retrigger_irq,
3435 };
3436 
3437 int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
3438 {
3439 	struct irq_chip *chip = &hpet_msi_type;
3440 	struct msi_msg msg;
3441 	int ret;
3442 
3443 	if (intr_remapping_enabled) {
3444 		struct intel_iommu *iommu = map_hpet_to_ir(id);
3445 		int index;
3446 
3447 		if (!iommu)
3448 			return -1;
3449 
3450 		index = alloc_irte(iommu, irq, 1);
3451 		if (index < 0)
3452 			return -1;
3453 	}
3454 
3455 	ret = msi_compose_msg(NULL, irq, &msg, id);
3456 	if (ret < 0)
3457 		return ret;
3458 
3459 	hpet_msi_write(irq_get_handler_data(irq), &msg);
3460 	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
3461 	if (irq_remapped(irq_get_chip_data(irq)))
3462 		chip = &ir_hpet_msi_type;
3463 
3464 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
3465 	return 0;
3466 }
3467 #endif
3468 
3469 #endif /* CONFIG_PCI_MSI */
3470 /*
3471  * Hypertransport interrupt support
3472  */
3473 #ifdef CONFIG_HT_IRQ
3474 
3475 #ifdef CONFIG_SMP
3476 
3477 static void target_ht_irq(unsigned int irq, unsigned int dest, u8 vector)
3478 {
3479 	struct ht_irq_msg msg;
3480 	fetch_ht_irq_msg(irq, &msg);
3481 
3482 	msg.address_lo &= ~(HT_IRQ_LOW_VECTOR_MASK | HT_IRQ_LOW_DEST_ID_MASK);
3483 	msg.address_hi &= ~(HT_IRQ_HIGH_DEST_ID_MASK);
3484 
3485 	msg.address_lo |= HT_IRQ_LOW_VECTOR(vector) | HT_IRQ_LOW_DEST_ID(dest);
3486 	msg.address_hi |= HT_IRQ_HIGH_DEST_ID(dest);
3487 
3488 	write_ht_irq_msg(irq, &msg);
3489 }
3490 
3491 static int
3492 ht_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
3493 {
3494 	struct irq_cfg *cfg = data->chip_data;
3495 	unsigned int dest;
3496 
3497 	if (__ioapic_set_affinity(data, mask, &dest))
3498 		return -1;
3499 
3500 	target_ht_irq(data->irq, dest, cfg->vector);
3501 	return 0;
3502 }
3503 
3504 #endif
3505 
3506 static struct irq_chip ht_irq_chip = {
3507 	.name			= "PCI-HT",
3508 	.irq_mask		= mask_ht_irq,
3509 	.irq_unmask		= unmask_ht_irq,
3510 	.irq_ack		= ack_apic_edge,
3511 #ifdef CONFIG_SMP
3512 	.irq_set_affinity	= ht_set_affinity,
3513 #endif
3514 	.irq_retrigger		= ioapic_retrigger_irq,
3515 };
3516 
3517 int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
3518 {
3519 	struct irq_cfg *cfg;
3520 	int err;
3521 
3522 	if (disable_apic)
3523 		return -ENXIO;
3524 
3525 	cfg = irq_cfg(irq);
3526 	err = assign_irq_vector(irq, cfg, apic->target_cpus());
3527 	if (!err) {
3528 		struct ht_irq_msg msg;
3529 		unsigned dest;
3530 
3531 		dest = apic->cpu_mask_to_apicid_and(cfg->domain,
3532 						    apic->target_cpus());
3533 
3534 		msg.address_hi = HT_IRQ_HIGH_DEST_ID(dest);
3535 
3536 		msg.address_lo =
3537 			HT_IRQ_LOW_BASE |
3538 			HT_IRQ_LOW_DEST_ID(dest) |
3539 			HT_IRQ_LOW_VECTOR(cfg->vector) |
3540 			((apic->irq_dest_mode == 0) ?
3541 				HT_IRQ_LOW_DM_PHYSICAL :
3542 				HT_IRQ_LOW_DM_LOGICAL) |
3543 			HT_IRQ_LOW_RQEOI_EDGE |
3544 			((apic->irq_delivery_mode != dest_LowestPrio) ?
3545 				HT_IRQ_LOW_MT_FIXED :
3546 				HT_IRQ_LOW_MT_ARBITRATED) |
3547 			HT_IRQ_LOW_IRQ_MASKED;
3548 
3549 		write_ht_irq_msg(irq, &msg);
3550 
3551 		irq_set_chip_and_handler_name(irq, &ht_irq_chip,
3552 					      handle_edge_irq, "edge");
3553 
3554 		dev_printk(KERN_DEBUG, &dev->dev, "irq %d for HT\n", irq);
3555 	}
3556 	return err;
3557 }
3558 #endif /* CONFIG_HT_IRQ */
3559 
3560 static int
3561 io_apic_setup_irq_pin(unsigned int irq, int node, struct io_apic_irq_attr *attr)
3562 {
3563 	struct irq_cfg *cfg = alloc_irq_and_cfg_at(irq, node);
3564 	int ret;
3565 
3566 	if (!cfg)
3567 		return -EINVAL;
3568 	ret = __add_pin_to_irq_node(cfg, node, attr->ioapic, attr->ioapic_pin);
3569 	if (!ret)
3570 		setup_ioapic_irq(irq, cfg, attr);
3571 	return ret;
3572 }
3573 
3574 int io_apic_setup_irq_pin_once(unsigned int irq, int node,
3575 			       struct io_apic_irq_attr *attr)
3576 {
3577 	unsigned int id = attr->ioapic, pin = attr->ioapic_pin;
3578 	int ret;
3579 
3580 	/* Avoid redundant programming */
3581 	if (test_bit(pin, ioapics[id].pin_programmed)) {
3582 		pr_debug("Pin %d-%d already programmed\n",
3583 			 mpc_ioapic_id(id), pin);
3584 		return 0;
3585 	}
3586 	ret = io_apic_setup_irq_pin(irq, node, attr);
3587 	if (!ret)
3588 		set_bit(pin, ioapics[id].pin_programmed);
3589 	return ret;
3590 }
3591 
3592 static int __init io_apic_get_redir_entries(int ioapic)
3593 {
3594 	union IO_APIC_reg_01	reg_01;
3595 	unsigned long flags;
3596 
3597 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3598 	reg_01.raw = io_apic_read(ioapic, 1);
3599 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3600 
3601 	/* The register returns the maximum index redir index
3602 	 * supported, which is one less than the total number of redir
3603 	 * entries.
3604 	 */
3605 	return reg_01.bits.entries + 1;
3606 }
3607 
3608 static void __init probe_nr_irqs_gsi(void)
3609 {
3610 	int nr;
3611 
3612 	nr = gsi_top + NR_IRQS_LEGACY;
3613 	if (nr > nr_irqs_gsi)
3614 		nr_irqs_gsi = nr;
3615 
3616 	printk(KERN_DEBUG "nr_irqs_gsi: %d\n", nr_irqs_gsi);
3617 }
3618 
3619 int get_nr_irqs_gsi(void)
3620 {
3621 	return nr_irqs_gsi;
3622 }
3623 
3624 #ifdef CONFIG_SPARSE_IRQ
3625 int __init arch_probe_nr_irqs(void)
3626 {
3627 	int nr;
3628 
3629 	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
3630 		nr_irqs = NR_VECTORS * nr_cpu_ids;
3631 
3632 	nr = nr_irqs_gsi + 8 * nr_cpu_ids;
3633 #if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
3634 	/*
3635 	 * for MSI and HT dyn irq
3636 	 */
3637 	nr += nr_irqs_gsi * 16;
3638 #endif
3639 	if (nr < nr_irqs)
3640 		nr_irqs = nr;
3641 
3642 	return NR_IRQS_LEGACY;
3643 }
3644 #endif
3645 
3646 int io_apic_set_pci_routing(struct device *dev, int irq,
3647 			    struct io_apic_irq_attr *irq_attr)
3648 {
3649 	int node;
3650 
3651 	if (!IO_APIC_IRQ(irq)) {
3652 		apic_printk(APIC_QUIET,KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
3653 			    irq_attr->ioapic);
3654 		return -EINVAL;
3655 	}
3656 
3657 	node = dev ? dev_to_node(dev) : cpu_to_node(0);
3658 
3659 	return io_apic_setup_irq_pin_once(irq, node, irq_attr);
3660 }
3661 
3662 #ifdef CONFIG_X86_32
3663 static int __init io_apic_get_unique_id(int ioapic, int apic_id)
3664 {
3665 	union IO_APIC_reg_00 reg_00;
3666 	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
3667 	physid_mask_t tmp;
3668 	unsigned long flags;
3669 	int i = 0;
3670 
3671 	/*
3672 	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
3673 	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
3674 	 * supports up to 16 on one shared APIC bus.
3675 	 *
3676 	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
3677 	 *      advantage of new APIC bus architecture.
3678 	 */
3679 
3680 	if (physids_empty(apic_id_map))
3681 		apic->ioapic_phys_id_map(&phys_cpu_present_map, &apic_id_map);
3682 
3683 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3684 	reg_00.raw = io_apic_read(ioapic, 0);
3685 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3686 
3687 	if (apic_id >= get_physical_broadcast()) {
3688 		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
3689 			"%d\n", ioapic, apic_id, reg_00.bits.ID);
3690 		apic_id = reg_00.bits.ID;
3691 	}
3692 
3693 	/*
3694 	 * Every APIC in a system must have a unique ID or we get lots of nice
3695 	 * 'stuck on smp_invalidate_needed IPI wait' messages.
3696 	 */
3697 	if (apic->check_apicid_used(&apic_id_map, apic_id)) {
3698 
3699 		for (i = 0; i < get_physical_broadcast(); i++) {
3700 			if (!apic->check_apicid_used(&apic_id_map, i))
3701 				break;
3702 		}
3703 
3704 		if (i == get_physical_broadcast())
3705 			panic("Max apic_id exceeded!\n");
3706 
3707 		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
3708 			"trying %d\n", ioapic, apic_id, i);
3709 
3710 		apic_id = i;
3711 	}
3712 
3713 	apic->apicid_to_cpu_present(apic_id, &tmp);
3714 	physids_or(apic_id_map, apic_id_map, tmp);
3715 
3716 	if (reg_00.bits.ID != apic_id) {
3717 		reg_00.bits.ID = apic_id;
3718 
3719 		raw_spin_lock_irqsave(&ioapic_lock, flags);
3720 		io_apic_write(ioapic, 0, reg_00.raw);
3721 		reg_00.raw = io_apic_read(ioapic, 0);
3722 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3723 
3724 		/* Sanity check */
3725 		if (reg_00.bits.ID != apic_id) {
3726 			printk("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
3727 			return -1;
3728 		}
3729 	}
3730 
3731 	apic_printk(APIC_VERBOSE, KERN_INFO
3732 			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
3733 
3734 	return apic_id;
3735 }
3736 
3737 static u8 __init io_apic_unique_id(u8 id)
3738 {
3739 	if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
3740 	    !APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
3741 		return io_apic_get_unique_id(nr_ioapics, id);
3742 	else
3743 		return id;
3744 }
3745 #else
3746 static u8 __init io_apic_unique_id(u8 id)
3747 {
3748 	int i;
3749 	DECLARE_BITMAP(used, 256);
3750 
3751 	bitmap_zero(used, 256);
3752 	for (i = 0; i < nr_ioapics; i++) {
3753 		__set_bit(mpc_ioapic_id(i), used);
3754 	}
3755 	if (!test_bit(id, used))
3756 		return id;
3757 	return find_first_zero_bit(used, 256);
3758 }
3759 #endif
3760 
3761 static int __init io_apic_get_version(int ioapic)
3762 {
3763 	union IO_APIC_reg_01	reg_01;
3764 	unsigned long flags;
3765 
3766 	raw_spin_lock_irqsave(&ioapic_lock, flags);
3767 	reg_01.raw = io_apic_read(ioapic, 1);
3768 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
3769 
3770 	return reg_01.bits.version;
3771 }
3772 
3773 int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity)
3774 {
3775 	int ioapic, pin, idx;
3776 
3777 	if (skip_ioapic_setup)
3778 		return -1;
3779 
3780 	ioapic = mp_find_ioapic(gsi);
3781 	if (ioapic < 0)
3782 		return -1;
3783 
3784 	pin = mp_find_ioapic_pin(ioapic, gsi);
3785 	if (pin < 0)
3786 		return -1;
3787 
3788 	idx = find_irq_entry(ioapic, pin, mp_INT);
3789 	if (idx < 0)
3790 		return -1;
3791 
3792 	*trigger = irq_trigger(idx);
3793 	*polarity = irq_polarity(idx);
3794 	return 0;
3795 }
3796 
3797 /*
3798  * This function currently is only a helper for the i386 smp boot process where
3799  * we need to reprogram the ioredtbls to cater for the cpus which have come online
3800  * so mask in all cases should simply be apic->target_cpus()
3801  */
3802 #ifdef CONFIG_SMP
3803 void __init setup_ioapic_dest(void)
3804 {
3805 	int pin, ioapic, irq, irq_entry;
3806 	const struct cpumask *mask;
3807 	struct irq_data *idata;
3808 
3809 	if (skip_ioapic_setup == 1)
3810 		return;
3811 
3812 	for (ioapic = 0; ioapic < nr_ioapics; ioapic++)
3813 	for (pin = 0; pin < ioapics[ioapic].nr_registers; pin++) {
3814 		irq_entry = find_irq_entry(ioapic, pin, mp_INT);
3815 		if (irq_entry == -1)
3816 			continue;
3817 		irq = pin_2_irq(irq_entry, ioapic, pin);
3818 
3819 		if ((ioapic > 0) && (irq > 16))
3820 			continue;
3821 
3822 		idata = irq_get_irq_data(irq);
3823 
3824 		/*
3825 		 * Honour affinities which have been set in early boot
3826 		 */
3827 		if (!irqd_can_balance(idata) || irqd_affinity_was_set(idata))
3828 			mask = idata->affinity;
3829 		else
3830 			mask = apic->target_cpus();
3831 
3832 		if (intr_remapping_enabled)
3833 			ir_ioapic_set_affinity(idata, mask, false);
3834 		else
3835 			ioapic_set_affinity(idata, mask, false);
3836 	}
3837 
3838 }
3839 #endif
3840 
3841 #define IOAPIC_RESOURCE_NAME_SIZE 11
3842 
3843 static struct resource *ioapic_resources;
3844 
3845 static struct resource * __init ioapic_setup_resources(int nr_ioapics)
3846 {
3847 	unsigned long n;
3848 	struct resource *res;
3849 	char *mem;
3850 	int i;
3851 
3852 	if (nr_ioapics <= 0)
3853 		return NULL;
3854 
3855 	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
3856 	n *= nr_ioapics;
3857 
3858 	mem = alloc_bootmem(n);
3859 	res = (void *)mem;
3860 
3861 	mem += sizeof(struct resource) * nr_ioapics;
3862 
3863 	for (i = 0; i < nr_ioapics; i++) {
3864 		res[i].name = mem;
3865 		res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
3866 		snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
3867 		mem += IOAPIC_RESOURCE_NAME_SIZE;
3868 	}
3869 
3870 	ioapic_resources = res;
3871 
3872 	return res;
3873 }
3874 
3875 void __init ioapic_and_gsi_init(void)
3876 {
3877 	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
3878 	struct resource *ioapic_res;
3879 	int i;
3880 
3881 	ioapic_res = ioapic_setup_resources(nr_ioapics);
3882 	for (i = 0; i < nr_ioapics; i++) {
3883 		if (smp_found_config) {
3884 			ioapic_phys = mpc_ioapic_addr(i);
3885 #ifdef CONFIG_X86_32
3886 			if (!ioapic_phys) {
3887 				printk(KERN_ERR
3888 				       "WARNING: bogus zero IO-APIC "
3889 				       "address found in MPTABLE, "
3890 				       "disabling IO/APIC support!\n");
3891 				smp_found_config = 0;
3892 				skip_ioapic_setup = 1;
3893 				goto fake_ioapic_page;
3894 			}
3895 #endif
3896 		} else {
3897 #ifdef CONFIG_X86_32
3898 fake_ioapic_page:
3899 #endif
3900 			ioapic_phys = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
3901 			ioapic_phys = __pa(ioapic_phys);
3902 		}
3903 		set_fixmap_nocache(idx, ioapic_phys);
3904 		apic_printk(APIC_VERBOSE, "mapped IOAPIC to %08lx (%08lx)\n",
3905 			__fix_to_virt(idx) + (ioapic_phys & ~PAGE_MASK),
3906 			ioapic_phys);
3907 		idx++;
3908 
3909 		ioapic_res->start = ioapic_phys;
3910 		ioapic_res->end = ioapic_phys + IO_APIC_SLOT_SIZE - 1;
3911 		ioapic_res++;
3912 	}
3913 
3914 	probe_nr_irqs_gsi();
3915 }
3916 
3917 void __init ioapic_insert_resources(void)
3918 {
3919 	int i;
3920 	struct resource *r = ioapic_resources;
3921 
3922 	if (!r) {
3923 		if (nr_ioapics > 0)
3924 			printk(KERN_ERR
3925 				"IO APIC resources couldn't be allocated.\n");
3926 		return;
3927 	}
3928 
3929 	for (i = 0; i < nr_ioapics; i++) {
3930 		insert_resource(&iomem_resource, r);
3931 		r++;
3932 	}
3933 }
3934 
3935 int mp_find_ioapic(u32 gsi)
3936 {
3937 	int i = 0;
3938 
3939 	if (nr_ioapics == 0)
3940 		return -1;
3941 
3942 	/* Find the IOAPIC that manages this GSI. */
3943 	for (i = 0; i < nr_ioapics; i++) {
3944 		struct mp_ioapic_gsi *gsi_cfg = mp_ioapic_gsi_routing(i);
3945 		if ((gsi >= gsi_cfg->gsi_base)
3946 		    && (gsi <= gsi_cfg->gsi_end))
3947 			return i;
3948 	}
3949 
3950 	printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
3951 	return -1;
3952 }
3953 
3954 int mp_find_ioapic_pin(int ioapic, u32 gsi)
3955 {
3956 	struct mp_ioapic_gsi *gsi_cfg;
3957 
3958 	if (WARN_ON(ioapic == -1))
3959 		return -1;
3960 
3961 	gsi_cfg = mp_ioapic_gsi_routing(ioapic);
3962 	if (WARN_ON(gsi > gsi_cfg->gsi_end))
3963 		return -1;
3964 
3965 	return gsi - gsi_cfg->gsi_base;
3966 }
3967 
3968 static __init int bad_ioapic(unsigned long address)
3969 {
3970 	if (nr_ioapics >= MAX_IO_APICS) {
3971 		printk(KERN_WARNING "WARNING: Max # of I/O APICs (%d) exceeded "
3972 		       "(found %d), skipping\n", MAX_IO_APICS, nr_ioapics);
3973 		return 1;
3974 	}
3975 	if (!address) {
3976 		printk(KERN_WARNING "WARNING: Bogus (zero) I/O APIC address"
3977 		       " found in table, skipping!\n");
3978 		return 1;
3979 	}
3980 	return 0;
3981 }
3982 
3983 void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
3984 {
3985 	int idx = 0;
3986 	int entries;
3987 	struct mp_ioapic_gsi *gsi_cfg;
3988 
3989 	if (bad_ioapic(address))
3990 		return;
3991 
3992 	idx = nr_ioapics;
3993 
3994 	ioapics[idx].mp_config.type = MP_IOAPIC;
3995 	ioapics[idx].mp_config.flags = MPC_APIC_USABLE;
3996 	ioapics[idx].mp_config.apicaddr = address;
3997 
3998 	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
3999 	ioapics[idx].mp_config.apicid = io_apic_unique_id(id);
4000 	ioapics[idx].mp_config.apicver = io_apic_get_version(idx);
4001 
4002 	/*
4003 	 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
4004 	 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
4005 	 */
4006 	entries = io_apic_get_redir_entries(idx);
4007 	gsi_cfg = mp_ioapic_gsi_routing(idx);
4008 	gsi_cfg->gsi_base = gsi_base;
4009 	gsi_cfg->gsi_end = gsi_base + entries - 1;
4010 
4011 	/*
4012 	 * The number of IO-APIC IRQ registers (== #pins):
4013 	 */
4014 	ioapics[idx].nr_registers = entries;
4015 
4016 	if (gsi_cfg->gsi_end >= gsi_top)
4017 		gsi_top = gsi_cfg->gsi_end + 1;
4018 
4019 	printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%x, "
4020 	       "GSI %d-%d\n", idx, mpc_ioapic_id(idx),
4021 	       mpc_ioapic_ver(idx), mpc_ioapic_addr(idx),
4022 	       gsi_cfg->gsi_base, gsi_cfg->gsi_end);
4023 
4024 	nr_ioapics++;
4025 }
4026 
4027 /* Enable IOAPIC early just for system timer */
4028 void __init pre_init_apic_IRQ0(void)
4029 {
4030 	struct io_apic_irq_attr attr = { 0, 0, 0, 0 };
4031 
4032 	printk(KERN_INFO "Early APIC setup for system timer0\n");
4033 #ifndef CONFIG_SMP
4034 	physid_set_mask_of_physid(boot_cpu_physical_apicid,
4035 					 &phys_cpu_present_map);
4036 #endif
4037 	setup_local_APIC();
4038 
4039 	io_apic_setup_irq_pin(0, 0, &attr);
4040 	irq_set_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq,
4041 				      "edge");
4042 }
4043