x86, apic: move APIC drivers to arch/x86/kernel/apic/*

arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.

Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4160 insertions, 0 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
new file mode 100644
index 0000000..00e6071
--- /dev/null
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -0,0 +1,4160 @@
+/*
+ *	Intel IO-APIC support for multi-Pentium hosts.
+ *
+ *	Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
+ *
+ *	Many thanks to Stig Venaas for trying out countless experimental
+ *	patches and reporting/debugging problems patiently!
+ *
+ *	(c) 1999, Multiple IO-APIC support, developed by
+ *	Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
+ *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
+ *	further tested and cleaned up by Zach Brown <zab@redhat.com>
+ *	and Ingo Molnar <mingo@redhat.com>
+ *
+ *	Fixes
+ *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
+ *					thanks to Eric Gilmore
+ *					and Rolf G. Tews
+ *					for testing these extensively
+ *	Paul Diefenbaugh	:	Added full ACPI support
+ */
+
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/pci.h>
+#include <linux/mc146818rtc.h>
+#include <linux/compiler.h>
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/sysdev.h>
+#include <linux/msi.h>
+#include <linux/htirq.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/jiffies.h>	/* time_after() */
+#ifdef CONFIG_ACPI
+#include <acpi/acpi_bus.h>
+#endif
+#include <linux/bootmem.h>
+#include <linux/dmar.h>
+#include <linux/hpet.h>
+
+#include <asm/idle.h>
+#include <asm/io.h>
+#include <asm/smp.h>
+#include <asm/cpu.h>
+#include <asm/desc.h>
+#include <asm/proto.h>
+#include <asm/acpi.h>
+#include <asm/dma.h>
+#include <asm/timer.h>
+#include <asm/i8259.h>
+#include <asm/nmi.h>
+#include <asm/msidef.h>
+#include <asm/hypertransport.h>
+#include <asm/setup.h>
+#include <asm/irq_remapping.h>
+#include <asm/hpet.h>
+#include <asm/uv/uv_hub.h>
+#include <asm/uv/uv_irq.h>
+
+#include <asm/apic.h>
+
+#define __apicdebuginit(type) static type __init
+
+/*
+ *      Is the SiS APIC rmw bug present ?
+ *      -1 = don't know, 0 = no, 1 = yes
+ */
+int sis_apic_bug = -1;
+
+static DEFINE_SPINLOCK(ioapic_lock);
+static DEFINE_SPINLOCK(vector_lock);
+
+/*
+ * # of IRQ routing registers
+ */
+int nr_ioapic_registers[MAX_IO_APICS];
+
+/* I/O APIC entries */
+struct mpc_ioapic mp_ioapics[MAX_IO_APICS];
+int nr_ioapics;
+
+/* MP IRQ source entries */
+struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
+
+/* # of MP IRQ source entries */
+int mp_irq_entries;
+
+#if defined (CONFIG_MCA) || defined (CONFIG_EISA)
+int mp_bus_id_to_type[MAX_MP_BUSSES];
+#endif
+
+DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
+
+int skip_ioapic_setup;
+
+void arch_disable_smp_support(void)
+{
+#ifdef CONFIG_PCI
+	noioapicquirk = 1;
+	noioapicreroute = -1;
+#endif
+	skip_ioapic_setup = 1;
+}
+
+static int __init parse_noapic(char *str)
+{
+	/* disable IO-APIC */
+	arch_disable_smp_support();
+	return 0;
+}
+early_param("noapic", parse_noapic);
+
+struct irq_pin_list;
+
+/*
+ * This is performance-critical, we want to do it O(1)
+ *
+ * the indexing order of this array favors 1:1 mappings
+ * between pins and IRQs.
+ */
+
+struct irq_pin_list {
+	int apic, pin;
+	struct irq_pin_list *next;
+};
+
+static struct irq_pin_list *get_one_free_irq_2_pin(int cpu)
+{
+	struct irq_pin_list *pin;
+	int node;
+
+	node = cpu_to_node(cpu);
+
+	pin = kzalloc_node(sizeof(*pin), GFP_ATOMIC, node);
+
+	return pin;
+}
+
+struct irq_cfg {
+	struct irq_pin_list *irq_2_pin;
+	cpumask_var_t domain;
+	cpumask_var_t old_domain;
+	unsigned move_cleanup_count;
+	u8 vector;
+	u8 move_in_progress : 1;
+#ifdef CONFIG_NUMA_MIGRATE_IRQ_DESC
+	u8 move_desc_pending : 1;
+#endif
+};
+
+/* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
+#ifdef CONFIG_SPARSE_IRQ
+static struct irq_cfg irq_cfgx[] = {
+#else
+static struct irq_cfg irq_cfgx[NR_IRQS] = {
+#endif
+	[0]  = { .vector = IRQ0_VECTOR,  },
+	[1]  = { .vector = IRQ1_VECTOR,  },
+	[2]  = { .vector = IRQ2_VECTOR,  },
+	[3]  = { .vector = IRQ3_VECTOR,  },
+	[4]  = { .vector = IRQ4_VECTOR,  },
+	[5]  = { .vector = IRQ5_VECTOR,  },
+	[6]  = { .vector = IRQ6_VECTOR,  },
+	[7]  = { .vector = IRQ7_VECTOR,  },
+	[8]  = { .vector = IRQ8_VECTOR,  },
+	[9]  = { .vector = IRQ9_VECTOR,  },
+	[10] = { .vector = IRQ10_VECTOR, },
+	[11] = { .vector = IRQ11_VECTOR, },
+	[12] = { .vector = IRQ12_VECTOR, },
+	[13] = { .vector = IRQ13_VECTOR, },
+	[14] = { .vector = IRQ14_VECTOR, },
+	[15] = { .vector = IRQ15_VECTOR, },
+};
+
+int __init arch_early_irq_init(void)
+{
+	struct irq_cfg *cfg;
+	struct irq_desc *desc;
+	int count;
+	int i;
+
+	cfg = irq_cfgx;
+	count = ARRAY_SIZE(irq_cfgx);
+
+	for (i = 0; i < count; i++) {
+		desc = irq_to_desc(i);
+		desc->chip_data = &cfg[i];
+		alloc_bootmem_cpumask_var(&cfg[i].domain);
+		alloc_bootmem_cpumask_var(&cfg[i].old_domain);
+		if (i < NR_IRQS_LEGACY)
+			cpumask_setall(cfg[i].domain);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_SPARSE_IRQ
+static struct irq_cfg *irq_cfg(unsigned int irq)
+{
+	struct irq_cfg *cfg = NULL;
+	struct irq_desc *desc;
+
+	desc = irq_to_desc(irq);
+	if (desc)
+		cfg = desc->chip_data;
+
+	return cfg;
+}
+
+static struct irq_cfg *get_one_free_irq_cfg(int cpu)
+{
+	struct irq_cfg *cfg;
+	int node;
+
+	node = cpu_to_node(cpu);
+
+	cfg = kzalloc_node(sizeof(*cfg), GFP_ATOMIC, node);
+	if (cfg) {
+		if (!alloc_cpumask_var_node(&cfg->domain, GFP_ATOMIC, node)) {
+			kfree(cfg);
+			cfg = NULL;
+		} else if (!alloc_cpumask_var_node(&cfg->old_domain,
+							  GFP_ATOMIC, node)) {
+			free_cpumask_var(cfg->domain);
+			kfree(cfg);
+			cfg = NULL;
+		} else {
+			cpumask_clear(cfg->domain);
+			cpumask_clear(cfg->old_domain);
+		}
+	}
+
+	return cfg;
+}
+
+int arch_init_chip_data(struct irq_desc *desc, int cpu)
+{
+	struct irq_cfg *cfg;
+
+	cfg = desc->chip_data;
+	if (!cfg) {
+		desc->chip_data = get_one_free_irq_cfg(cpu);
+		if (!desc->chip_data) {
+			printk(KERN_ERR "can not alloc irq_cfg\n");
+			BUG_ON(1);
+		}
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_NUMA_MIGRATE_IRQ_DESC
+
+static void
+init_copy_irq_2_pin(struct irq_cfg *old_cfg, struct irq_cfg *cfg, int cpu)
+{
+	struct irq_pin_list *old_entry, *head, *tail, *entry;
+
+	cfg->irq_2_pin = NULL;
+	old_entry = old_cfg->irq_2_pin;
+	if (!old_entry)
+		return;
+
+	entry = get_one_free_irq_2_pin(cpu);
+	if (!entry)
+		return;
+
+	entry->apic	= old_entry->apic;
+	entry->pin	= old_entry->pin;
+	head		= entry;
+	tail		= entry;
+	old_entry	= old_entry->next;
+	while (old_entry) {
+		entry = get_one_free_irq_2_pin(cpu);
+		if (!entry) {
+			entry = head;
+			while (entry) {
+				head = entry->next;
+				kfree(entry);
+				entry = head;
+			}
+			/* still use the old one */
+			return;
+		}
+		entry->apic	= old_entry->apic;
+		entry->pin	= old_entry->pin;
+		tail->next	= entry;
+		tail		= entry;
+		old_entry	= old_entry->next;
+	}
+
+	tail->next = NULL;
+	cfg->irq_2_pin = head;
+}
+
+static void free_irq_2_pin(struct irq_cfg *old_cfg, struct irq_cfg *cfg)
+{
+	struct irq_pin_list *entry, *next;
+
+	if (old_cfg->irq_2_pin == cfg->irq_2_pin)
+		return;
+
+	entry = old_cfg->irq_2_pin;
+
+	while (entry) {
+		next = entry->next;
+		kfree(entry);
+		entry = next;
+	}
+	old_cfg->irq_2_pin = NULL;
+}
+
+void arch_init_copy_chip_data(struct irq_desc *old_desc,
+				 struct irq_desc *desc, int cpu)
+{
+	struct irq_cfg *cfg;
+	struct irq_cfg *old_cfg;
+
+	cfg = get_one_free_irq_cfg(cpu);
+
+	if (!cfg)
+		return;
+
+	desc->chip_data = cfg;
+
+	old_cfg = old_desc->chip_data;
+
+	memcpy(cfg, old_cfg, sizeof(struct irq_cfg));
+
+	init_copy_irq_2_pin(old_cfg, cfg, cpu);
+}
+
+static void free_irq_cfg(struct irq_cfg *old_cfg)
+{
+	kfree(old_cfg);
+}
+
+void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc)
+{
+	struct irq_cfg *old_cfg, *cfg;
+
+	old_cfg = old_desc->chip_data;
+	cfg = desc->chip_data;
+
+	if (old_cfg == cfg)
+		return;
+
+	if (old_cfg) {
+		free_irq_2_pin(old_cfg, cfg);
+		free_irq_cfg(old_cfg);
+		old_desc->chip_data = NULL;
+	}
+}
+
+static void
+set_extra_move_desc(struct irq_desc *desc, const struct cpumask *mask)
+{
+	struct irq_cfg *cfg = desc->chip_data;
+
+	if (!cfg->move_in_progress) {
+		/* it means that domain is not changed */
+		if (!cpumask_intersects(desc->affinity, mask))
+			cfg->move_desc_pending = 1;
+	}
+}
+#endif
+
+#else
+static struct irq_cfg *irq_cfg(unsigned int irq)
+{
+	return irq < nr_irqs ? irq_cfgx + irq : NULL;
+}
+
+#endif
+
+#ifndef CONFIG_NUMA_MIGRATE_IRQ_DESC
+static inline void
+set_extra_move_desc(struct irq_desc *desc, const struct cpumask *mask)
+{
+}
+#endif
+
+struct io_apic {
+	unsigned int index;
+	unsigned int unused[3];
+	unsigned int data;
+};
+
+static __attribute_const__ struct io_apic __iomem *io_apic_base(int idx)
+{
+	return (void __iomem *) __fix_to_virt(FIX_IO_APIC_BASE_0 + idx)
+		+ (mp_ioapics[idx].apicaddr & ~PAGE_MASK);
+}
+
+static inline unsigned int io_apic_read(unsigned int apic, unsigned int reg)
+{
+	struct io_apic __iomem *io_apic = io_apic_base(apic);
+	writel(reg, &io_apic->index);
+	return readl(&io_apic->data);
+}
+
+static inline void io_apic_write(unsigned int apic, unsigned int reg, unsigned int value)
+{
+	struct io_apic __iomem *io_apic = io_apic_base(apic);
+	writel(reg, &io_apic->index);
+	writel(value, &io_apic->data);
+}
+
+/*
+ * Re-write a value: to be used for read-modify-write
+ * cycles where the read already set up the index register.
+ *
+ * Older SiS APIC requires we rewrite the index register
+ */
+static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned int value)
+{
+	struct io_apic __iomem *io_apic = io_apic_base(apic);
+
+	if (sis_apic_bug)
+		writel(reg, &io_apic->index);
+	writel(value, &io_apic->data);
+}
+
+static bool io_apic_level_ack_pending(struct irq_cfg *cfg)
+{
+	struct irq_pin_list *entry;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	entry = cfg->irq_2_pin;
+	for (;;) {
+		unsigned int reg;
+		int pin;
+
+		if (!entry)
+			break;
+		pin = entry->pin;
+		reg = io_apic_read(entry->apic, 0x10 + pin*2);
+		/* Is the remote IRR bit set? */
+		if (reg & IO_APIC_REDIR_REMOTE_IRR) {
+			spin_unlock_irqrestore(&ioapic_lock, flags);
+			return true;
+		}
+		if (!entry->next)
+			break;
+		entry = entry->next;
+	}
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	return false;
+}
+
+union entry_union {
+	struct { u32 w1, w2; };
+	struct IO_APIC_route_entry entry;
+};
+
+static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
+{
+	union entry_union eu;
+	unsigned long flags;
+	spin_lock_irqsave(&ioapic_lock, flags);
+	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
+	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+	return eu.entry;
+}
+
+/*
+ * When we write a new IO APIC routing entry, we need to write the high
+ * word first! If the mask bit in the low word is clear, we will enable
+ * the interrupt, and we need to make sure the entry is fully populated
+ * before that happens.
+ */
+static void
+__ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
+{
+	union entry_union eu;
+	eu.entry = e;
+	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
+	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
+}
+
+void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&ioapic_lock, flags);
+	__ioapic_write_entry(apic, pin, e);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+/*
+ * When we mask an IO APIC routing entry, we need to write the low
+ * word first, in order to set the mask bit before we change the
+ * high bits!
+ */
+static void ioapic_mask_entry(int apic, int pin)
+{
+	unsigned long flags;
+	union entry_union eu = { .entry.mask = 1 };
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
+	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+#ifdef CONFIG_SMP
+static void send_cleanup_vector(struct irq_cfg *cfg)
+{
+	cpumask_var_t cleanup_mask;
+
+	if (unlikely(!alloc_cpumask_var(&cleanup_mask, GFP_ATOMIC))) {
+		unsigned int i;
+		cfg->move_cleanup_count = 0;
+		for_each_cpu_and(i, cfg->old_domain, cpu_online_mask)
+			cfg->move_cleanup_count++;
+		for_each_cpu_and(i, cfg->old_domain, cpu_online_mask)
+			apic->send_IPI_mask(cpumask_of(i), IRQ_MOVE_CLEANUP_VECTOR);
+	} else {
+		cpumask_and(cleanup_mask, cfg->old_domain, cpu_online_mask);
+		cfg->move_cleanup_count = cpumask_weight(cleanup_mask);
+		apic->send_IPI_mask(cleanup_mask, IRQ_MOVE_CLEANUP_VECTOR);
+		free_cpumask_var(cleanup_mask);
+	}
+	cfg->move_in_progress = 0;
+}
+
+static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, struct irq_cfg *cfg)
+{
+	int apic, pin;
+	struct irq_pin_list *entry;
+	u8 vector = cfg->vector;
+
+	entry = cfg->irq_2_pin;
+	for (;;) {
+		unsigned int reg;
+
+		if (!entry)
+			break;
+
+		apic = entry->apic;
+		pin = entry->pin;
+#ifdef CONFIG_INTR_REMAP
+		/*
+		 * With interrupt-remapping, destination information comes
+		 * from interrupt-remapping table entry.
+		 */
+		if (!irq_remapped(irq))
+			io_apic_write(apic, 0x11 + pin*2, dest);
+#else
+		io_apic_write(apic, 0x11 + pin*2, dest);
+#endif
+		reg = io_apic_read(apic, 0x10 + pin*2);
+		reg &= ~IO_APIC_REDIR_VECTOR_MASK;
+		reg |= vector;
+		io_apic_modify(apic, 0x10 + pin*2, reg);
+		if (!entry->next)
+			break;
+		entry = entry->next;
+	}
+}
+
+static int
+assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask);
+
+/*
+ * Either sets desc->affinity to a valid value, and returns
+ * ->cpu_mask_to_apicid of that, or returns BAD_APICID and
+ * leaves desc->affinity untouched.
+ */
+static unsigned int
+set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask)
+{
+	struct irq_cfg *cfg;
+	unsigned int irq;
+
+	if (!cpumask_intersects(mask, cpu_online_mask))
+		return BAD_APICID;
+
+	irq = desc->irq;
+	cfg = desc->chip_data;
+	if (assign_irq_vector(irq, cfg, mask))
+		return BAD_APICID;
+
+	cpumask_and(desc->affinity, cfg->domain, mask);
+	set_extra_move_desc(desc, mask);
+
+	return apic->cpu_mask_to_apicid_and(desc->affinity, cpu_online_mask);
+}
+
+static void
+set_ioapic_affinity_irq_desc(struct irq_desc *desc, const struct cpumask *mask)
+{
+	struct irq_cfg *cfg;
+	unsigned long flags;
+	unsigned int dest;
+	unsigned int irq;
+
+	irq = desc->irq;
+	cfg = desc->chip_data;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	dest = set_desc_affinity(desc, mask);
+	if (dest != BAD_APICID) {
+		/* Only the high 8 bits are valid. */
+		dest = SET_APIC_LOGICAL_ID(dest);
+		__target_IO_APIC_irq(irq, dest, cfg);
+	}
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+static void
+set_ioapic_affinity_irq(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc;
+
+	desc = irq_to_desc(irq);
+
+	set_ioapic_affinity_irq_desc(desc, mask);
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
+ * shared ISA-space IRQs, so we have to support them. We are super
+ * fast in the common case, and fast for shared ISA-space IRQs.
+ */
+static void add_pin_to_irq_cpu(struct irq_cfg *cfg, int cpu, int apic, int pin)
+{
+	struct irq_pin_list *entry;
+
+	entry = cfg->irq_2_pin;
+	if (!entry) {
+		entry = get_one_free_irq_2_pin(cpu);
+		if (!entry) {
+			printk(KERN_ERR "can not alloc irq_2_pin to add %d - %d\n",
+					apic, pin);
+			return;
+		}
+		cfg->irq_2_pin = entry;
+		entry->apic = apic;
+		entry->pin = pin;
+		return;
+	}
+
+	while (entry->next) {
+		/* not again, please */
+		if (entry->apic == apic && entry->pin == pin)
+			return;
+
+		entry = entry->next;
+	}
+
+	entry->next = get_one_free_irq_2_pin(cpu);
+	entry = entry->next;
+	entry->apic = apic;
+	entry->pin = pin;
+}
+
+/*
+ * Reroute an IRQ to a different pin.
+ */
+static void __init replace_pin_at_irq_cpu(struct irq_cfg *cfg, int cpu,
+				      int oldapic, int oldpin,
+				      int newapic, int newpin)
+{
+	struct irq_pin_list *entry = cfg->irq_2_pin;
+	int replaced = 0;
+
+	while (entry) {
+		if (entry->apic == oldapic && entry->pin == oldpin) {
+			entry->apic = newapic;
+			entry->pin = newpin;
+			replaced = 1;
+			/* every one is different, right? */
+			break;
+		}
+		entry = entry->next;
+	}
+
+	/* why? call replace before add? */
+	if (!replaced)
+		add_pin_to_irq_cpu(cfg, cpu, newapic, newpin);
+}
+
+static inline void io_apic_modify_irq(struct irq_cfg *cfg,
+				int mask_and, int mask_or,
+				void (*final)(struct irq_pin_list *entry))
+{
+	int pin;
+	struct irq_pin_list *entry;
+
+	for (entry = cfg->irq_2_pin; entry != NULL; entry = entry->next) {
+		unsigned int reg;
+		pin = entry->pin;
+		reg = io_apic_read(entry->apic, 0x10 + pin * 2);
+		reg &= mask_and;
+		reg |= mask_or;
+		io_apic_modify(entry->apic, 0x10 + pin * 2, reg);
+		if (final)
+			final(entry);
+	}
+}
+
+static void __unmask_IO_APIC_irq(struct irq_cfg *cfg)
+{
+	io_apic_modify_irq(cfg, ~IO_APIC_REDIR_MASKED, 0, NULL);
+}
+
+#ifdef CONFIG_X86_64
+static void io_apic_sync(struct irq_pin_list *entry)
+{
+	/*
+	 * Synchronize the IO-APIC and the CPU by doing
+	 * a dummy read from the IO-APIC
+	 */
+	struct io_apic __iomem *io_apic;
+	io_apic = io_apic_base(entry->apic);
+	readl(&io_apic->data);
+}
+
+static void __mask_IO_APIC_irq(struct irq_cfg *cfg)
+{
+	io_apic_modify_irq(cfg, ~0, IO_APIC_REDIR_MASKED, &io_apic_sync);
+}
+#else /* CONFIG_X86_32 */
+static void __mask_IO_APIC_irq(struct irq_cfg *cfg)
+{
+	io_apic_modify_irq(cfg, ~0, IO_APIC_REDIR_MASKED, NULL);
+}
+
+static void __mask_and_edge_IO_APIC_irq(struct irq_cfg *cfg)
+{
+	io_apic_modify_irq(cfg, ~IO_APIC_REDIR_LEVEL_TRIGGER,
+			IO_APIC_REDIR_MASKED, NULL);
+}
+
+static void __unmask_and_level_IO_APIC_irq(struct irq_cfg *cfg)
+{
+	io_apic_modify_irq(cfg, ~IO_APIC_REDIR_MASKED,
+			IO_APIC_REDIR_LEVEL_TRIGGER, NULL);
+}
+#endif /* CONFIG_X86_32 */
+
+static void mask_IO_APIC_irq_desc(struct irq_desc *desc)
+{
+	struct irq_cfg *cfg = desc->chip_data;
+	unsigned long flags;
+
+	BUG_ON(!cfg);
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	__mask_IO_APIC_irq(cfg);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+static void unmask_IO_APIC_irq_desc(struct irq_desc *desc)
+{
+	struct irq_cfg *cfg = desc->chip_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	__unmask_IO_APIC_irq(cfg);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
+static void mask_IO_APIC_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	mask_IO_APIC_irq_desc(desc);
+}
+static void unmask_IO_APIC_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	unmask_IO_APIC_irq_desc(desc);
+}
+
+static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
+{
+	struct IO_APIC_route_entry entry;
+
+	/* Check delivery_mode to be sure we're not clearing an SMI pin */
+	entry = ioapic_read_entry(apic, pin);
+	if (entry.delivery_mode == dest_SMI)
+		return;
+	/*
+	 * Disable it in the IO-APIC irq-routing table:
+	 */
+	ioapic_mask_entry(apic, pin);
+}
+
+static void clear_IO_APIC (void)
+{
+	int apic, pin;
+
+	for (apic = 0; apic < nr_ioapics; apic++)
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
+			clear_IO_APIC_pin(apic, pin);
+}
+
+#ifdef CONFIG_X86_32
+/*
+ * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
+ * specific CPU-side IRQs.
+ */
+
+#define MAX_PIRQS 8
+static int pirq_entries[MAX_PIRQS] = {
+	[0 ... MAX_PIRQS - 1] = -1
+};
+
+static int __init ioapic_pirq_setup(char *str)
+{
+	int i, max;
+	int ints[MAX_PIRQS+1];
+
+	get_options(str, ARRAY_SIZE(ints), ints);
+
+	apic_printk(APIC_VERBOSE, KERN_INFO
+			"PIRQ redirection, working around broken MP-BIOS.\n");
+	max = MAX_PIRQS;
+	if (ints[0] < MAX_PIRQS)
+		max = ints[0];
+
+	for (i = 0; i < max; i++) {
+		apic_printk(APIC_VERBOSE, KERN_DEBUG
+				"... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
+		/*
+		 * PIRQs are mapped upside down, usually.
+		 */
+		pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
+	}
+	return 1;
+}
+
+__setup("pirq=", ioapic_pirq_setup);
+#endif /* CONFIG_X86_32 */
+
+#ifdef CONFIG_INTR_REMAP
+/* I/O APIC RTE contents at the OS boot up */
+static struct IO_APIC_route_entry *early_ioapic_entries[MAX_IO_APICS];
+
+/*
+ * Saves and masks all the unmasked IO-APIC RTE's
+ */
+int save_mask_IO_APIC_setup(void)
+{
+	union IO_APIC_reg_01 reg_01;
+	unsigned long flags;
+	int apic, pin;
+
+	/*
+	 * The number of IO-APIC IRQ registers (== #pins):
+	 */
+	for (apic = 0; apic < nr_ioapics; apic++) {
+		spin_lock_irqsave(&ioapic_lock, flags);
+		reg_01.raw = io_apic_read(apic, 1);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+		nr_ioapic_registers[apic] = reg_01.bits.entries+1;
+	}
+
+	for (apic = 0; apic < nr_ioapics; apic++) {
+		early_ioapic_entries[apic] =
+			kzalloc(sizeof(struct IO_APIC_route_entry) *
+				nr_ioapic_registers[apic], GFP_KERNEL);
+		if (!early_ioapic_entries[apic])
+			goto nomem;
+	}
+
+	for (apic = 0; apic < nr_ioapics; apic++)
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
+			struct IO_APIC_route_entry entry;
+
+			entry = early_ioapic_entries[apic][pin] =
+				ioapic_read_entry(apic, pin);
+			if (!entry.mask) {
+				entry.mask = 1;
+				ioapic_write_entry(apic, pin, entry);
+			}
+		}
+
+	return 0;
+
+nomem:
+	while (apic >= 0)
+		kfree(early_ioapic_entries[apic--]);
+	memset(early_ioapic_entries, 0,
+		ARRAY_SIZE(early_ioapic_entries));
+
+	return -ENOMEM;
+}
+
+void restore_IO_APIC_setup(void)
+{
+	int apic, pin;
+
+	for (apic = 0; apic < nr_ioapics; apic++) {
+		if (!early_ioapic_entries[apic])
+			break;
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
+			ioapic_write_entry(apic, pin,
+					   early_ioapic_entries[apic][pin]);
+		kfree(early_ioapic_entries[apic]);
+		early_ioapic_entries[apic] = NULL;
+	}
+}
+
+void reinit_intr_remapped_IO_APIC(int intr_remapping)
+{
+	/*
+	 * for now plain restore of previous settings.
+	 * TBD: In the case of OS enabling interrupt-remapping,
+	 * IO-APIC RTE's need to be setup to point to interrupt-remapping
+	 * table entries. for now, do a plain restore, and wait for
+	 * the setup_IO_APIC_irqs() to do proper initialization.
+	 */
+	restore_IO_APIC_setup();
+}
+#endif
+
+/*
+ * Find the IRQ entry number of a certain pin.
+ */
+static int find_irq_entry(int apic, int pin, int type)
+{
+	int i;
+
+	for (i = 0; i < mp_irq_entries; i++)
+		if (mp_irqs[i].irqtype == type &&
+		    (mp_irqs[i].dstapic == mp_ioapics[apic].apicid ||
+		     mp_irqs[i].dstapic == MP_APIC_ALL) &&
+		    mp_irqs[i].dstirq == pin)
+			return i;
+
+	return -1;
+}
+
+/*
+ * Find the pin to which IRQ[irq] (ISA) is connected
+ */
+static int __init find_isa_irq_pin(int irq, int type)
+{
+	int i;
+
+	for (i = 0; i < mp_irq_entries; i++) {
+		int lbus = mp_irqs[i].srcbus;
+
+		if (test_bit(lbus, mp_bus_not_pci) &&
+		    (mp_irqs[i].irqtype == type) &&
+		    (mp_irqs[i].srcbusirq == irq))
+
+			return mp_irqs[i].dstirq;
+	}
+	return -1;
+}
+
+static int __init find_isa_irq_apic(int irq, int type)
+{
+	int i;
+
+	for (i = 0; i < mp_irq_entries; i++) {
+		int lbus = mp_irqs[i].srcbus;
+
+		if (test_bit(lbus, mp_bus_not_pci) &&
+		    (mp_irqs[i].irqtype == type) &&
+		    (mp_irqs[i].srcbusirq == irq))
+			break;
+	}
+	if (i < mp_irq_entries) {
+		int apic;
+		for(apic = 0; apic < nr_ioapics; apic++) {
+			if (mp_ioapics[apic].apicid == mp_irqs[i].dstapic)
+				return apic;
+		}
+	}
+
+	return -1;
+}
+
+/*
+ * Find a specific PCI IRQ entry.
+ * Not an __init, possibly needed by modules
+ */
+static int pin_2_irq(int idx, int apic, int pin);
+
+int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
+{
+	int apic, i, best_guess = -1;
+
+	apic_printk(APIC_DEBUG, "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
+		bus, slot, pin);
+	if (test_bit(bus, mp_bus_not_pci)) {
+		apic_printk(APIC_VERBOSE, "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
+		return -1;
+	}
+	for (i = 0; i < mp_irq_entries; i++) {
+		int lbus = mp_irqs[i].srcbus;
+
+		for (apic = 0; apic < nr_ioapics; apic++)
+			if (mp_ioapics[apic].apicid == mp_irqs[i].dstapic ||
+			    mp_irqs[i].dstapic == MP_APIC_ALL)
+				break;
+
+		if (!test_bit(lbus, mp_bus_not_pci) &&
+		    !mp_irqs[i].irqtype &&
+		    (bus == lbus) &&
+		    (slot == ((mp_irqs[i].srcbusirq >> 2) & 0x1f))) {
+			int irq = pin_2_irq(i, apic, mp_irqs[i].dstirq);
+
+			if (!(apic || IO_APIC_IRQ(irq)))
+				continue;
+
+			if (pin == (mp_irqs[i].srcbusirq & 3))
+				return irq;
+			/*
+			 * Use the first all-but-pin matching entry as a
+			 * best-guess fuzzy result for broken mptables.
+			 */
+			if (best_guess < 0)
+				best_guess = irq;
+		}
+	}
+	return best_guess;
+}
+
+EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
+
+#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+/*
+ * EISA Edge/Level control register, ELCR
+ */
+static int EISA_ELCR(unsigned int irq)
+{
+	if (irq < NR_IRQS_LEGACY) {
+		unsigned int port = 0x4d0 + (irq >> 3);
+		return (inb(port) >> (irq & 7)) & 1;
+	}
+	apic_printk(APIC_VERBOSE, KERN_INFO
+			"Broken MPtable reports ISA irq %d\n", irq);
+	return 0;
+}
+
+#endif
+
+/* ISA interrupts are always polarity zero edge triggered,
+ * when listed as conforming in the MP table. */
+
+#define default_ISA_trigger(idx)	(0)
+#define default_ISA_polarity(idx)	(0)
+
+/* EISA interrupts are always polarity zero and can be edge or level
+ * trigger depending on the ELCR value.  If an interrupt is listed as
+ * EISA conforming in the MP table, that means its trigger type must
+ * be read in from the ELCR */
+
+#define default_EISA_trigger(idx)	(EISA_ELCR(mp_irqs[idx].srcbusirq))
+#define default_EISA_polarity(idx)	default_ISA_polarity(idx)
+
+/* PCI interrupts are always polarity one level triggered,
+ * when listed as conforming in the MP table. */
+
+#define default_PCI_trigger(idx)	(1)
+#define default_PCI_polarity(idx)	(1)
+
+/* MCA interrupts are always polarity zero level triggered,
+ * when listed as conforming in the MP table. */
+
+#define default_MCA_trigger(idx)	(1)
+#define default_MCA_polarity(idx)	default_ISA_polarity(idx)
+
+static int MPBIOS_polarity(int idx)
+{
+	int bus = mp_irqs[idx].srcbus;
+	int polarity;
+
+	/*
+	 * Determine IRQ line polarity (high active or low active):
+	 */
+	switch (mp_irqs[idx].irqflag & 3)
+	{
+		case 0: /* conforms, ie. bus-type dependent polarity */
+			if (test_bit(bus, mp_bus_not_pci))
+				polarity = default_ISA_polarity(idx);
+			else
+				polarity = default_PCI_polarity(idx);
+			break;
+		case 1: /* high active */
+		{
+			polarity = 0;
+			break;
+		}
+		case 2: /* reserved */
+		{
+			printk(KERN_WARNING "broken BIOS!!\n");
+			polarity = 1;
+			break;
+		}
+		case 3: /* low active */
+		{
+			polarity = 1;
+			break;
+		}
+		default: /* invalid */
+		{
+			printk(KERN_WARNING "broken BIOS!!\n");
+			polarity = 1;
+			break;
+		}
+	}
+	return polarity;
+}
+
+static int MPBIOS_trigger(int idx)
+{
+	int bus = mp_irqs[idx].srcbus;
+	int trigger;
+
+	/*
+	 * Determine IRQ trigger mode (edge or level sensitive):
+	 */
+	switch ((mp_irqs[idx].irqflag>>2) & 3)
+	{
+		case 0: /* conforms, ie. bus-type dependent */
+			if (test_bit(bus, mp_bus_not_pci))
+				trigger = default_ISA_trigger(idx);
+			else
+				trigger = default_PCI_trigger(idx);
+#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+			switch (mp_bus_id_to_type[bus]) {
+				case MP_BUS_ISA: /* ISA pin */
+				{
+					/* set before the switch */
+					break;
+				}
+				case MP_BUS_EISA: /* EISA pin */
+				{
+					trigger = default_EISA_trigger(idx);
+					break;
+				}
+				case MP_BUS_PCI: /* PCI pin */
+				{
+					/* set before the switch */
+					break;
+				}
+				case MP_BUS_MCA: /* MCA pin */
+				{
+					trigger = default_MCA_trigger(idx);
+					break;
+				}
+				default:
+				{
+					printk(KERN_WARNING "broken BIOS!!\n");
+					trigger = 1;
+					break;
+				}
+			}
+#endif
+			break;
+		case 1: /* edge */
+		{
+			trigger = 0;
+			break;
+		}
+		case 2: /* reserved */
+		{
+			printk(KERN_WARNING "broken BIOS!!\n");
+			trigger = 1;
+			break;
+		}
+		case 3: /* level */
+		{
+			trigger = 1;
+			break;
+		}
+		default: /* invalid */
+		{
+			printk(KERN_WARNING "broken BIOS!!\n");
+			trigger = 0;
+			break;
+		}
+	}
+	return trigger;
+}
+
+static inline int irq_polarity(int idx)
+{
+	return MPBIOS_polarity(idx);
+}
+
+static inline int irq_trigger(int idx)
+{
+	return MPBIOS_trigger(idx);
+}
+
+int (*ioapic_renumber_irq)(int ioapic, int irq);
+static int pin_2_irq(int idx, int apic, int pin)
+{
+	int irq, i;
+	int bus = mp_irqs[idx].srcbus;
+
+	/*
+	 * Debugging check, we are in big trouble if this message pops up!
+	 */
+	if (mp_irqs[idx].dstirq != pin)
+		printk(KERN_ERR "broken BIOS or MPTABLE parser, ayiee!!\n");
+
+	if (test_bit(bus, mp_bus_not_pci)) {
+		irq = mp_irqs[idx].srcbusirq;
+	} else {
+		/*
+		 * PCI IRQs are mapped in order
+		 */
+		i = irq = 0;
+		while (i < apic)
+			irq += nr_ioapic_registers[i++];
+		irq += pin;
+		/*
+                 * For MPS mode, so far only needed by ES7000 platform
+                 */
+		if (ioapic_renumber_irq)
+			irq = ioapic_renumber_irq(apic, irq);
+	}
+
+#ifdef CONFIG_X86_32
+	/*
+	 * PCI IRQ command line redirection. Yes, limits are hardcoded.
+	 */
+	if ((pin >= 16) && (pin <= 23)) {
+		if (pirq_entries[pin-16] != -1) {
+			if (!pirq_entries[pin-16]) {
+				apic_printk(APIC_VERBOSE, KERN_DEBUG
+						"disabling PIRQ%d\n", pin-16);
+			} else {
+				irq = pirq_entries[pin-16];
+				apic_printk(APIC_VERBOSE, KERN_DEBUG
+						"using PIRQ%d -> IRQ %d\n",
+						pin-16, irq);
+			}
+		}
+	}
+#endif
+
+	return irq;
+}
+
+void lock_vector_lock(void)
+{
+	/* Used to the online set of cpus does not change
+	 * during assign_irq_vector.
+	 */
+	spin_lock(&vector_lock);
+}
+
+void unlock_vector_lock(void)
+{
+	spin_unlock(&vector_lock);
+}
+
+static int
+__assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
+{
+	/*
+	 * NOTE! The local APIC isn't very good at handling
+	 * multiple interrupts at the same interrupt level.
+	 * As the interrupt level is determined by taking the
+	 * vector number and shifting that right by 4, we
+	 * want to spread these out a bit so that they don't
+	 * all fall in the same interrupt level.
+	 *
+	 * Also, we've got to be careful not to trash gate
+	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
+	 */
+	static int current_vector = FIRST_DEVICE_VECTOR, current_offset = 0;
+	unsigned int old_vector;
+	int cpu, err;
+	cpumask_var_t tmp_mask;
+
+	if ((cfg->move_in_progress) || cfg->move_cleanup_count)
+		return -EBUSY;
+
+	if (!alloc_cpumask_var(&tmp_mask, GFP_ATOMIC))
+		return -ENOMEM;
+
+	old_vector = cfg->vector;
+	if (old_vector) {
+		cpumask_and(tmp_mask, mask, cpu_online_mask);
+		cpumask_and(tmp_mask, cfg->domain, tmp_mask);
+		if (!cpumask_empty(tmp_mask)) {
+			free_cpumask_var(tmp_mask);
+			return 0;
+		}
+	}
+
+	/* Only try and allocate irqs on cpus that are present */
+	err = -ENOSPC;
+	for_each_cpu_and(cpu, mask, cpu_online_mask) {
+		int new_cpu;
+		int vector, offset;
+
+		apic->vector_allocation_domain(cpu, tmp_mask);
+
+		vector = current_vector;
+		offset = current_offset;
+next:
+		vector += 8;
+		if (vector >= first_system_vector) {
+			/* If out of vectors on large boxen, must share them. */
+			offset = (offset + 1) % 8;
+			vector = FIRST_DEVICE_VECTOR + offset;
+		}
+		if (unlikely(current_vector == vector))
+			continue;
+
+		if (test_bit(vector, used_vectors))
+			goto next;
+
+		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
+			if (per_cpu(vector_irq, new_cpu)[vector] != -1)
+				goto next;
+		/* Found one! */
+		current_vector = vector;
+		current_offset = offset;
+		if (old_vector) {
+			cfg->move_in_progress = 1;
+			cpumask_copy(cfg->old_domain, cfg->domain);
+		}
+		for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
+			per_cpu(vector_irq, new_cpu)[vector] = irq;
+		cfg->vector = vector;
+		cpumask_copy(cfg->domain, tmp_mask);
+		err = 0;
+		break;
+	}
+	free_cpumask_var(tmp_mask);
+	return err;
+}
+
+static int
+assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
+{
+	int err;
+	unsigned long flags;
+
+	spin_lock_irqsave(&vector_lock, flags);
+	err = __assign_irq_vector(irq, cfg, mask);
+	spin_unlock_irqrestore(&vector_lock, flags);
+	return err;
+}
+
+static void __clear_irq_vector(int irq, struct irq_cfg *cfg)
+{
+	int cpu, vector;
+
+	BUG_ON(!cfg->vector);
+
+	vector = cfg->vector;
+	for_each_cpu_and(cpu, cfg->domain, cpu_online_mask)
+		per_cpu(vector_irq, cpu)[vector] = -1;
+
+	cfg->vector = 0;
+	cpumask_clear(cfg->domain);
+
+	if (likely(!cfg->move_in_progress))
+		return;
+	for_each_cpu_and(cpu, cfg->old_domain, cpu_online_mask) {
+		for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
+								vector++) {
+			if (per_cpu(vector_irq, cpu)[vector] != irq)
+				continue;
+			per_cpu(vector_irq, cpu)[vector] = -1;
+			break;
+		}
+	}
+	cfg->move_in_progress = 0;
+}
+
+void __setup_vector_irq(int cpu)
+{
+	/* Initialize vector_irq on a new cpu */
+	/* This function must be called with vector_lock held */
+	int irq, vector;
+	struct irq_cfg *cfg;
+	struct irq_desc *desc;
+
+	/* Mark the inuse vectors */
+	for_each_irq_desc(irq, desc) {
+		cfg = desc->chip_data;
+		if (!cpumask_test_cpu(cpu, cfg->domain))
+			continue;
+		vector = cfg->vector;
+		per_cpu(vector_irq, cpu)[vector] = irq;
+	}
+	/* Mark the free vectors */
+	for (vector = 0; vector < NR_VECTORS; ++vector) {
+		irq = per_cpu(vector_irq, cpu)[vector];
+		if (irq < 0)
+			continue;
+
+		cfg = irq_cfg(irq);
+		if (!cpumask_test_cpu(cpu, cfg->domain))
+			per_cpu(vector_irq, cpu)[vector] = -1;
+	}
+}
+
+static struct irq_chip ioapic_chip;
+#ifdef CONFIG_INTR_REMAP
+static struct irq_chip ir_ioapic_chip;
+#endif
+
+#define IOAPIC_AUTO     -1
+#define IOAPIC_EDGE     0
+#define IOAPIC_LEVEL    1
+
+#ifdef CONFIG_X86_32
+static inline int IO_APIC_irq_trigger(int irq)
+{
+	int apic, idx, pin;
+
+	for (apic = 0; apic < nr_ioapics; apic++) {
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
+			idx = find_irq_entry(apic, pin, mp_INT);
+			if ((idx != -1) && (irq == pin_2_irq(idx, apic, pin)))
+				return irq_trigger(idx);
+		}
+	}
+	/*
+         * nonexistent IRQs are edge default
+         */
+	return 0;
+}
+#else
+static inline int IO_APIC_irq_trigger(int irq)
+{
+	return 1;
+}
+#endif
+
+static void ioapic_register_intr(int irq, struct irq_desc *desc, unsigned long trigger)
+{
+
+	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
+	    trigger == IOAPIC_LEVEL)
+		desc->status |= IRQ_LEVEL;
+	else
+		desc->status &= ~IRQ_LEVEL;
+
+#ifdef CONFIG_INTR_REMAP
+	if (irq_remapped(irq)) {
+		desc->status |= IRQ_MOVE_PCNTXT;
+		if (trigger)
+			set_irq_chip_and_handler_name(irq, &ir_ioapic_chip,
+						      handle_fasteoi_irq,
+						     "fasteoi");
+		else
+			set_irq_chip_and_handler_name(irq, &ir_ioapic_chip,
+						      handle_edge_irq, "edge");
+		return;
+	}
+#endif
+	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
+	    trigger == IOAPIC_LEVEL)
+		set_irq_chip_and_handler_name(irq, &ioapic_chip,
+					      handle_fasteoi_irq,
+					      "fasteoi");
+	else
+		set_irq_chip_and_handler_name(irq, &ioapic_chip,
+					      handle_edge_irq, "edge");
+}
+
+int setup_ioapic_entry(int apic_id, int irq,
+		       struct IO_APIC_route_entry *entry,
+		       unsigned int destination, int trigger,
+		       int polarity, int vector)
+{
+	/*
+	 * add it to the IO-APIC irq-routing table:
+	 */
+	memset(entry,0,sizeof(*entry));
+
+#ifdef CONFIG_INTR_REMAP
+	if (intr_remapping_enabled) {
+		struct intel_iommu *iommu = map_ioapic_to_ir(apic_id);
+		struct irte irte;
+		struct IR_IO_APIC_route_entry *ir_entry =
+			(struct IR_IO_APIC_route_entry *) entry;
+		int index;
+
+		if (!iommu)
+			panic("No mapping iommu for ioapic %d\n", apic_id);
+
+		index = alloc_irte(iommu, irq, 1);
+		if (index < 0)
+			panic("Failed to allocate IRTE for ioapic %d\n", apic_id);
+
+		memset(&irte, 0, sizeof(irte));
+
+		irte.present = 1;
+		irte.dst_mode = apic->irq_dest_mode;
+		irte.trigger_mode = trigger;
+		irte.dlvry_mode = apic->irq_delivery_mode;
+		irte.vector = vector;
+		irte.dest_id = IRTE_DEST(destination);
+
+		modify_irte(irq, &irte);
+
+		ir_entry->index2 = (index >> 15) & 0x1;
+		ir_entry->zero = 0;
+		ir_entry->format = 1;
+		ir_entry->index = (index & 0x7fff);
+	} else
+#endif
+	{
+		entry->delivery_mode = apic->irq_delivery_mode;
+		entry->dest_mode = apic->irq_dest_mode;
+		entry->dest = destination;
+	}
+
+	entry->mask = 0;				/* enable IRQ */
+	entry->trigger = trigger;
+	entry->polarity = polarity;
+	entry->vector = vector;
+
+	/* Mask level triggered irqs.
+	 * Use IRQ_DELAYED_DISABLE for edge triggered irqs.
+	 */
+	if (trigger)
+		entry->mask = 1;
+	return 0;
+}
+
+static void setup_IO_APIC_irq(int apic_id, int pin, unsigned int irq, struct irq_desc *desc,
+			      int trigger, int polarity)
+{
+	struct irq_cfg *cfg;
+	struct IO_APIC_route_entry entry;
+	unsigned int dest;
+
+	if (!IO_APIC_IRQ(irq))
+		return;
+
+	cfg = desc->chip_data;
+
+	if (assign_irq_vector(irq, cfg, apic->target_cpus()))
+		return;
+
+	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
+
+	apic_printk(APIC_VERBOSE,KERN_DEBUG
+		    "IOAPIC[%d]: Set routing entry (%d-%d -> 0x%x -> "
+		    "IRQ %d Mode:%i Active:%i)\n",
+		    apic_id, mp_ioapics[apic_id].apicid, pin, cfg->vector,
+		    irq, trigger, polarity);
+
+
+	if (setup_ioapic_entry(mp_ioapics[apic_id].apicid, irq, &entry,
+			       dest, trigger, polarity, cfg->vector)) {
+		printk("Failed to setup ioapic entry for ioapic  %d, pin %d\n",
+		       mp_ioapics[apic_id].apicid, pin);
+		__clear_irq_vector(irq, cfg);
+		return;
+	}
+
+	ioapic_register_intr(irq, desc, trigger);
+	if (irq < NR_IRQS_LEGACY)
+		disable_8259A_irq(irq);
+
+	ioapic_write_entry(apic_id, pin, entry);
+}
+
+static void __init setup_IO_APIC_irqs(void)
+{
+	int apic_id, pin, idx, irq;
+	int notcon = 0;
+	struct irq_desc *desc;
+	struct irq_cfg *cfg;
+	int cpu = boot_cpu_id;
+
+	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");
+
+	for (apic_id = 0; apic_id < nr_ioapics; apic_id++) {
+		for (pin = 0; pin < nr_ioapic_registers[apic_id]; pin++) {
+
+			idx = find_irq_entry(apic_id, pin, mp_INT);
+			if (idx == -1) {
+				if (!notcon) {
+					notcon = 1;
+					apic_printk(APIC_VERBOSE,
+						KERN_DEBUG " %d-%d",
+						mp_ioapics[apic_id].apicid, pin);
+				} else
+					apic_printk(APIC_VERBOSE, " %d-%d",
+						mp_ioapics[apic_id].apicid, pin);
+				continue;
+			}
+			if (notcon) {
+				apic_printk(APIC_VERBOSE,
+					" (apicid-pin) not connected\n");
+				notcon = 0;
+			}
+
+			irq = pin_2_irq(idx, apic_id, pin);
+
+			/*
+			 * Skip the timer IRQ if there's a quirk handler
+			 * installed and if it returns 1:
+			 */
+			if (apic->multi_timer_check &&
+					apic->multi_timer_check(apic_id, irq))
+				continue;
+
+			desc = irq_to_desc_alloc_cpu(irq, cpu);
+			if (!desc) {
+				printk(KERN_INFO "can not get irq_desc for %d\n", irq);
+				continue;
+			}
+			cfg = desc->chip_data;
+			add_pin_to_irq_cpu(cfg, cpu, apic_id, pin);
+
+			setup_IO_APIC_irq(apic_id, pin, irq, desc,
+					irq_trigger(idx), irq_polarity(idx));
+		}
+	}
+
+	if (notcon)
+		apic_printk(APIC_VERBOSE,
+			" (apicid-pin) not connected\n");
+}
+
+/*
+ * Set up the timer pin, possibly with the 8259A-master behind.
+ */
+static void __init setup_timer_IRQ0_pin(unsigned int apic_id, unsigned int pin,
+					int vector)
+{
+	struct IO_APIC_route_entry entry;
+
+#ifdef CONFIG_INTR_REMAP
+	if (intr_remapping_enabled)
+		return;
+#endif
+
+	memset(&entry, 0, sizeof(entry));
+
+	/*
+	 * We use logical delivery to get the timer IRQ
+	 * to the first CPU.
+	 */
+	entry.dest_mode = apic->irq_dest_mode;
+	entry.mask = 0;			/* don't mask IRQ for edge */
+	entry.dest = apic->cpu_mask_to_apicid(apic->target_cpus());
+	entry.delivery_mode = apic->irq_delivery_mode;
+	entry.polarity = 0;
+	entry.trigger = 0;
+	entry.vector = vector;
+
+	/*
+	 * The timer IRQ doesn't have to know that behind the
+	 * scene we may have a 8259A-master in AEOI mode ...
+	 */
+	set_irq_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq, "edge");
+
+	/*
+	 * Add it to the IO-APIC irq-routing table:
+	 */
+	ioapic_write_entry(apic_id, pin, entry);
+}
+
+
+__apicdebuginit(void) print_IO_APIC(void)
+{
+	int apic, i;
+	union IO_APIC_reg_00 reg_00;
+	union IO_APIC_reg_01 reg_01;
+	union IO_APIC_reg_02 reg_02;
+	union IO_APIC_reg_03 reg_03;
+	unsigned long flags;
+	struct irq_cfg *cfg;
+	struct irq_desc *desc;
+	unsigned int irq;
+
+	if (apic_verbosity == APIC_QUIET)
+		return;
+
+	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
+	for (i = 0; i < nr_ioapics; i++)
+		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
+		       mp_ioapics[i].apicid, nr_ioapic_registers[i]);
+
+	/*
+	 * We are a bit conservative about what we expect.  We have to
+	 * know about every hardware change ASAP.
+	 */
+	printk(KERN_INFO "testing the IO APIC.......................\n");
+
+	for (apic = 0; apic < nr_ioapics; apic++) {
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_00.raw = io_apic_read(apic, 0);
+	reg_01.raw = io_apic_read(apic, 1);
+	if (reg_01.bits.version >= 0x10)
+		reg_02.raw = io_apic_read(apic, 2);
+	if (reg_01.bits.version >= 0x20)
+		reg_03.raw = io_apic_read(apic, 3);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	printk("\n");
+	printk(KERN_DEBUG "IO APIC #%d......\n", mp_ioapics[apic].apicid);
+	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
+	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
+	printk(KERN_DEBUG ".......    : Delivery Type: %X\n", reg_00.bits.delivery_type);
+	printk(KERN_DEBUG ".......    : LTS          : %X\n", reg_00.bits.LTS);
+
+	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
+	printk(KERN_DEBUG ".......     : max redirection entries: %04X\n", reg_01.bits.entries);
+
+	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
+	printk(KERN_DEBUG ".......     : IO APIC version: %04X\n", reg_01.bits.version);
+
+	/*
+	 * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
+	 * but the value of reg_02 is read as the previous read register
+	 * value, so ignore it if reg_02 == reg_01.
+	 */
+	if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
+		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
+		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
+	}
+
+	/*
+	 * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
+	 * or reg_03, but the value of reg_0[23] is read as the previous read
+	 * register value, so ignore it if reg_03 == reg_0[12].
+	 */
+	if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
+	    reg_03.raw != reg_01.raw) {
+		printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
+		printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
+	}
+
+	printk(KERN_DEBUG ".... IRQ redirection table:\n");
+
+	printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
+			  " Stat Dmod Deli Vect:   \n");
+
+	for (i = 0; i <= reg_01.bits.entries; i++) {
+		struct IO_APIC_route_entry entry;
+
+		entry = ioapic_read_entry(apic, i);
+
+		printk(KERN_DEBUG " %02x %03X ",
+			i,
+			entry.dest
+		);
+
+		printk("%1d    %1d    %1d   %1d   %1d    %1d    %1d    %02X\n",
+			entry.mask,
+			entry.trigger,
+			entry.irr,
+			entry.polarity,
+			entry.delivery_status,
+			entry.dest_mode,
+			entry.delivery_mode,
+			entry.vector
+		);
+	}
+	}
+	printk(KERN_DEBUG "IRQ to pin mappings:\n");
+	for_each_irq_desc(irq, desc) {
+		struct irq_pin_list *entry;
+
+		cfg = desc->chip_data;
+		entry = cfg->irq_2_pin;
+		if (!entry)
+			continue;
+		printk(KERN_DEBUG "IRQ%d ", irq);
+		for (;;) {
+			printk("-> %d:%d", entry->apic, entry->pin);
+			if (!entry->next)
+				break;
+			entry = entry->next;
+		}
+		printk("\n");
+	}
+
+	printk(KERN_INFO ".................................... done.\n");
+
+	return;
+}
+
+__apicdebuginit(void) print_APIC_bitfield(int base)
+{
+	unsigned int v;
+	int i, j;
+
+	if (apic_verbosity == APIC_QUIET)
+		return;
+
+	printk(KERN_DEBUG "0123456789abcdef0123456789abcdef\n" KERN_DEBUG);
+	for (i = 0; i < 8; i++) {
+		v = apic_read(base + i*0x10);
+		for (j = 0; j < 32; j++) {
+			if (v & (1<<j))
+				printk("1");
+			else
+				printk("0");
+		}
+		printk("\n");
+	}
+}
+
+__apicdebuginit(void) print_local_APIC(void *dummy)
+{
+	unsigned int v, ver, maxlvt;
+	u64 icr;
+
+	if (apic_verbosity == APIC_QUIET)
+		return;
+
+	printk("\n" KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
+		smp_processor_id(), hard_smp_processor_id());
+	v = apic_read(APIC_ID);
+	printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, read_apic_id());
+	v = apic_read(APIC_LVR);
+	printk(KERN_INFO "... APIC VERSION: %08x\n", v);
+	ver = GET_APIC_VERSION(v);
+	maxlvt = lapic_get_maxlvt();
+
+	v = apic_read(APIC_TASKPRI);
+	printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
+
+	if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
+		if (!APIC_XAPIC(ver)) {
+			v = apic_read(APIC_ARBPRI);
+			printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
+			       v & APIC_ARBPRI_MASK);
+		}
+		v = apic_read(APIC_PROCPRI);
+		printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
+	}
+
+	/*
+	 * Remote read supported only in the 82489DX and local APIC for
+	 * Pentium processors.
+	 */
+	if (!APIC_INTEGRATED(ver) || maxlvt == 3) {
+		v = apic_read(APIC_RRR);
+		printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
+	}
+
+	v = apic_read(APIC_LDR);
+	printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
+	if (!x2apic_enabled()) {
+		v = apic_read(APIC_DFR);
+		printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
+	}
+	v = apic_read(APIC_SPIV);
+	printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);
+
+	printk(KERN_DEBUG "... APIC ISR field:\n");
+	print_APIC_bitfield(APIC_ISR);
+	printk(KERN_DEBUG "... APIC TMR field:\n");
+	print_APIC_bitfield(APIC_TMR);
+	printk(KERN_DEBUG "... APIC IRR field:\n");
+	print_APIC_bitfield(APIC_IRR);
+
+	if (APIC_INTEGRATED(ver)) {             /* !82489DX */
+		if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
+			apic_write(APIC_ESR, 0);
+
+		v = apic_read(APIC_ESR);
+		printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
+	}
+
+	icr = apic_icr_read();
+	printk(KERN_DEBUG "... APIC ICR: %08x\n", (u32)icr);
+	printk(KERN_DEBUG "... APIC ICR2: %08x\n", (u32)(icr >> 32));
+
+	v = apic_read(APIC_LVTT);
+	printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);
+
+	if (maxlvt > 3) {                       /* PC is LVT#4. */
+		v = apic_read(APIC_LVTPC);
+		printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
+	}
+	v = apic_read(APIC_LVT0);
+	printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
+	v = apic_read(APIC_LVT1);
+	printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);
+
+	if (maxlvt > 2) {			/* ERR is LVT#3. */
+		v = apic_read(APIC_LVTERR);
+		printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
+	}
+
+	v = apic_read(APIC_TMICT);
+	printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
+	v = apic_read(APIC_TMCCT);
+	printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
+	v = apic_read(APIC_TDCR);
+	printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);
+	printk("\n");
+}
+
+__apicdebuginit(void) print_all_local_APICs(void)
+{
+	int cpu;
+
+	preempt_disable();
+	for_each_online_cpu(cpu)
+		smp_call_function_single(cpu, print_local_APIC, NULL, 1);
+	preempt_enable();
+}
+
+__apicdebuginit(void) print_PIC(void)
+{
+	unsigned int v;
+	unsigned long flags;
+
+	if (apic_verbosity == APIC_QUIET)
+		return;
+
+	printk(KERN_DEBUG "\nprinting PIC contents\n");
+
+	spin_lock_irqsave(&i8259A_lock, flags);
+
+	v = inb(0xa1) << 8 | inb(0x21);
+	printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);
+
+	v = inb(0xa0) << 8 | inb(0x20);
+	printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);
+
+	outb(0x0b,0xa0);
+	outb(0x0b,0x20);
+	v = inb(0xa0) << 8 | inb(0x20);
+	outb(0x0a,0xa0);
+	outb(0x0a,0x20);
+
+	spin_unlock_irqrestore(&i8259A_lock, flags);
+
+	printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);
+
+	v = inb(0x4d1) << 8 | inb(0x4d0);
+	printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
+}
+
+__apicdebuginit(int) print_all_ICs(void)
+{
+	print_PIC();
+	print_all_local_APICs();
+	print_IO_APIC();
+
+	return 0;
+}
+
+fs_initcall(print_all_ICs);
+
+
+/* Where if anywhere is the i8259 connect in external int mode */
+static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
+
+void __init enable_IO_APIC(void)
+{
+	union IO_APIC_reg_01 reg_01;
+	int i8259_apic, i8259_pin;
+	int apic;
+	unsigned long flags;
+
+	/*
+	 * The number of IO-APIC IRQ registers (== #pins):
+	 */
+	for (apic = 0; apic < nr_ioapics; apic++) {
+		spin_lock_irqsave(&ioapic_lock, flags);
+		reg_01.raw = io_apic_read(apic, 1);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+		nr_ioapic_registers[apic] = reg_01.bits.entries+1;
+	}
+	for(apic = 0; apic < nr_ioapics; apic++) {
+		int pin;
+		/* See if any of the pins is in ExtINT mode */
+		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
+			struct IO_APIC_route_entry entry;
+			entry = ioapic_read_entry(apic, pin);
+
+			/* If the interrupt line is enabled and in ExtInt mode
+			 * I have found the pin where the i8259 is connected.
+			 */
+			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
+				ioapic_i8259.apic = apic;
+				ioapic_i8259.pin  = pin;
+				goto found_i8259;
+			}
+		}
+	}
+ found_i8259:
+	/* Look to see what if the MP table has reported the ExtINT */
+	/* If we could not find the appropriate pin by looking at the ioapic
+	 * the i8259 probably is not connected the ioapic but give the
+	 * mptable a chance anyway.
+	 */
+	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
+	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
+	/* Trust the MP table if nothing is setup in the hardware */
+	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
+		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
+		ioapic_i8259.pin  = i8259_pin;
+		ioapic_i8259.apic = i8259_apic;
+	}
+	/* Complain if the MP table and the hardware disagree */
+	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
+		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
+	{
+		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
+	}
+
+	/*
+	 * Do not trust the IO-APIC being empty at bootup
+	 */
+	clear_IO_APIC();
+}
+
+/*
+ * Not an __init, needed by the reboot code
+ */
+void disable_IO_APIC(void)
+{
+	/*
+	 * Clear the IO-APIC before rebooting:
+	 */
+	clear_IO_APIC();
+
+	/*
+	 * If the i8259 is routed through an IOAPIC
+	 * Put that IOAPIC in virtual wire mode
+	 * so legacy interrupts can be delivered.
+	 */
+	if (ioapic_i8259.pin != -1) {
+		struct IO_APIC_route_entry entry;
+
+		memset(&entry, 0, sizeof(entry));
+		entry.mask            = 0; /* Enabled */
+		entry.trigger         = 0; /* Edge */
+		entry.irr             = 0;
+		entry.polarity        = 0; /* High */
+		entry.delivery_status = 0;
+		entry.dest_mode       = 0; /* Physical */
+		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
+		entry.vector          = 0;
+		entry.dest            = read_apic_id();
+
+		/*
+		 * Add it to the IO-APIC irq-routing table:
+		 */
+		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
+	}
+
+	disconnect_bsp_APIC(ioapic_i8259.pin != -1);
+}
+
+#ifdef CONFIG_X86_32
+/*
+ * function to set the IO-APIC physical IDs based on the
+ * values stored in the MPC table.
+ *
+ * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
+ */
+
+static void __init setup_ioapic_ids_from_mpc(void)
+{
+	union IO_APIC_reg_00 reg_00;
+	physid_mask_t phys_id_present_map;
+	int apic_id;
+	int i;
+	unsigned char old_id;
+	unsigned long flags;
+
+	if (x86_quirks->setup_ioapic_ids && x86_quirks->setup_ioapic_ids())
+		return;
+
+	/*
+	 * Don't check I/O APIC IDs for xAPIC systems.  They have
+	 * no meaning without the serial APIC bus.
+	 */
+	if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+		|| APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
+		return;
+	/*
+	 * This is broken; anything with a real cpu count has to
+	 * circumvent this idiocy regardless.
+	 */
+	phys_id_present_map = apic->ioapic_phys_id_map(phys_cpu_present_map);
+
+	/*
+	 * Set the IOAPIC ID to the value stored in the MPC table.
+	 */
+	for (apic_id = 0; apic_id < nr_ioapics; apic_id++) {
+
+		/* Read the register 0 value */
+		spin_lock_irqsave(&ioapic_lock, flags);
+		reg_00.raw = io_apic_read(apic_id, 0);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+
+		old_id = mp_ioapics[apic_id].apicid;
+
+		if (mp_ioapics[apic_id].apicid >= get_physical_broadcast()) {
+			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
+				apic_id, mp_ioapics[apic_id].apicid);
+			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
+				reg_00.bits.ID);
+			mp_ioapics[apic_id].apicid = reg_00.bits.ID;
+		}
+
+		/*
+		 * Sanity check, is the ID really free? Every APIC in a
+		 * system must have a unique ID or we get lots of nice
+		 * 'stuck on smp_invalidate_needed IPI wait' messages.
+		 */
+		if (apic->check_apicid_used(phys_id_present_map,
+					mp_ioapics[apic_id].apicid)) {
+			printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
+				apic_id, mp_ioapics[apic_id].apicid);
+			for (i = 0; i < get_physical_broadcast(); i++)
+				if (!physid_isset(i, phys_id_present_map))
+					break;
+			if (i >= get_physical_broadcast())
+				panic("Max APIC ID exceeded!\n");
+			printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
+				i);
+			physid_set(i, phys_id_present_map);
+			mp_ioapics[apic_id].apicid = i;
+		} else {
+			physid_mask_t tmp;
+			tmp = apic->apicid_to_cpu_present(mp_ioapics[apic_id].apicid);
+			apic_printk(APIC_VERBOSE, "Setting %d in the "
+					"phys_id_present_map\n",
+					mp_ioapics[apic_id].apicid);
+			physids_or(phys_id_present_map, phys_id_present_map, tmp);
+		}
+
+
+		/*
+		 * We need to adjust the IRQ routing table
+		 * if the ID changed.
+		 */
+		if (old_id != mp_ioapics[apic_id].apicid)
+			for (i = 0; i < mp_irq_entries; i++)
+				if (mp_irqs[i].dstapic == old_id)
+					mp_irqs[i].dstapic
+						= mp_ioapics[apic_id].apicid;
+
+		/*
+		 * Read the right value from the MPC table and
+		 * write it into the ID register.
+		 */
+		apic_printk(APIC_VERBOSE, KERN_INFO
+			"...changing IO-APIC physical APIC ID to %d ...",
+			mp_ioapics[apic_id].apicid);
+
+		reg_00.bits.ID = mp_ioapics[apic_id].apicid;
+		spin_lock_irqsave(&ioapic_lock, flags);
+		io_apic_write(apic_id, 0, reg_00.raw);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+
+		/*
+		 * Sanity check
+		 */
+		spin_lock_irqsave(&ioapic_lock, flags);
+		reg_00.raw = io_apic_read(apic_id, 0);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+		if (reg_00.bits.ID != mp_ioapics[apic_id].apicid)
+			printk("could not set ID!\n");
+		else
+			apic_printk(APIC_VERBOSE, " ok.\n");
+	}
+}
+#endif
+
+int no_timer_check __initdata;
+
+static int __init notimercheck(char *s)
+{
+	no_timer_check = 1;
+	return 1;
+}
+__setup("no_timer_check", notimercheck);
+
+/*
+ * There is a nasty bug in some older SMP boards, their mptable lies
+ * about the timer IRQ. We do the following to work around the situation:
+ *
+ *	- timer IRQ defaults to IO-APIC IRQ
+ *	- if this function detects that timer IRQs are defunct, then we fall
+ *	  back to ISA timer IRQs
+ */
+static int __init timer_irq_works(void)
+{
+	unsigned long t1 = jiffies;
+	unsigned long flags;
+
+	if (no_timer_check)
+		return 1;
+
+	local_save_flags(flags);
+	local_irq_enable();
+	/* Let ten ticks pass... */
+	mdelay((10 * 1000) / HZ);
+	local_irq_restore(flags);
+
+	/*
+	 * Expect a few ticks at least, to be sure some possible
+	 * glue logic does not lock up after one or two first
+	 * ticks in a non-ExtINT mode.  Also the local APIC
+	 * might have cached one ExtINT interrupt.  Finally, at
+	 * least one tick may be lost due to delays.
+	 */
+
+	/* jiffies wrap? */
+	if (time_after(jiffies, t1 + 4))
+		return 1;
+	return 0;
+}
+
+/*
+ * In the SMP+IOAPIC case it might happen that there are an unspecified
+ * number of pending IRQ events unhandled. These cases are very rare,
+ * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
+ * better to do it this way as thus we do not have to be aware of
+ * 'pending' interrupts in the IRQ path, except at this point.
+ */
+/*
+ * Edge triggered needs to resend any interrupt
+ * that was delayed but this is now handled in the device
+ * independent code.
+ */
+
+/*
+ * Starting up a edge-triggered IO-APIC interrupt is
+ * nasty - we need to make sure that we get the edge.
+ * If it is already asserted for some reason, we need
+ * return 1 to indicate that is was pending.
+ *
+ * This is not complete - we should be able to fake
+ * an edge even if it isn't on the 8259A...
+ */
+
+static unsigned int startup_ioapic_irq(unsigned int irq)
+{
+	int was_pending = 0;
+	unsigned long flags;
+	struct irq_cfg *cfg;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	if (irq < NR_IRQS_LEGACY) {
+		disable_8259A_irq(irq);
+		if (i8259A_irq_pending(irq))
+			was_pending = 1;
+	}
+	cfg = irq_cfg(irq);
+	__unmask_IO_APIC_irq(cfg);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	return was_pending;
+}
+
+#ifdef CONFIG_X86_64
+static int ioapic_retrigger_irq(unsigned int irq)
+{
+
+	struct irq_cfg *cfg = irq_cfg(irq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&vector_lock, flags);
+	apic->send_IPI_mask(cpumask_of(cpumask_first(cfg->domain)), cfg->vector);
+	spin_unlock_irqrestore(&vector_lock, flags);
+
+	return 1;
+}
+#else
+static int ioapic_retrigger_irq(unsigned int irq)
+{
+	apic->send_IPI_self(irq_cfg(irq)->vector);
+
+	return 1;
+}
+#endif
+
+/*
+ * Level and edge triggered IO-APIC interrupts need different handling,
+ * so we use two separate IRQ descriptors. Edge triggered IRQs can be
+ * handled with the level-triggered descriptor, but that one has slightly
+ * more overhead. Level-triggered interrupts cannot be handled with the
+ * edge-triggered handler, without risking IRQ storms and other ugly
+ * races.
+ */
+
+#ifdef CONFIG_SMP
+
+#ifdef CONFIG_INTR_REMAP
+static void ir_irq_migration(struct work_struct *work);
+
+static DECLARE_DELAYED_WORK(ir_migration_work, ir_irq_migration);
+
+/*
+ * Migrate the IO-APIC irq in the presence of intr-remapping.
+ *
+ * For edge triggered, irq migration is a simple atomic update(of vector
+ * and cpu destination) of IRTE and flush the hardware cache.
+ *
+ * For level triggered, we need to modify the io-apic RTE aswell with the update
+ * vector information, along with modifying IRTE with vector and destination.
+ * So irq migration for level triggered is little  bit more complex compared to
+ * edge triggered migration. But the good news is, we use the same algorithm
+ * for level triggered migration as we have today, only difference being,
+ * we now initiate the irq migration from process context instead of the
+ * interrupt context.
+ *
+ * In future, when we do a directed EOI (combined with cpu EOI broadcast
+ * suppression) to the IO-APIC, level triggered irq migration will also be
+ * as simple as edge triggered migration and we can do the irq migration
+ * with a simple atomic update to IO-APIC RTE.
+ */
+static void
+migrate_ioapic_irq_desc(struct irq_desc *desc, const struct cpumask *mask)
+{
+	struct irq_cfg *cfg;
+	struct irte irte;
+	int modify_ioapic_rte;
+	unsigned int dest;
+	unsigned long flags;
+	unsigned int irq;
+
+	if (!cpumask_intersects(mask, cpu_online_mask))
+		return;
+
+	irq = desc->irq;
+	if (get_irte(irq, &irte))
+		return;
+
+	cfg = desc->chip_data;
+	if (assign_irq_vector(irq, cfg, mask))
+		return;
+
+	set_extra_move_desc(desc, mask);
+
+	dest = apic->cpu_mask_to_apicid_and(cfg->domain, mask);
+
+	modify_ioapic_rte = desc->status & IRQ_LEVEL;
+	if (modify_ioapic_rte) {
+		spin_lock_irqsave(&ioapic_lock, flags);
+		__target_IO_APIC_irq(irq, dest, cfg);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+	}
+
+	irte.vector = cfg->vector;
+	irte.dest_id = IRTE_DEST(dest);
+
+	/*
+	 * Modified the IRTE and flushes the Interrupt entry cache.
+	 */
+	modify_irte(irq, &irte);
+
+	if (cfg->move_in_progress)
+		send_cleanup_vector(cfg);
+
+	cpumask_copy(desc->affinity, mask);
+}
+
+static int migrate_irq_remapped_level_desc(struct irq_desc *desc)
+{
+	int ret = -1;
+	struct irq_cfg *cfg = desc->chip_data;
+
+	mask_IO_APIC_irq_desc(desc);
+
+	if (io_apic_level_ack_pending(cfg)) {
+		/*
+		 * Interrupt in progress. Migrating irq now will change the
+		 * vector information in the IO-APIC RTE and that will confuse
+		 * the EOI broadcast performed by cpu.
+		 * So, delay the irq migration to the next instance.
+		 */
+		schedule_delayed_work(&ir_migration_work, 1);
+		goto unmask;
+	}
+
+	/* everthing is clear. we have right of way */
+	migrate_ioapic_irq_desc(desc, desc->pending_mask);
+
+	ret = 0;
+	desc->status &= ~IRQ_MOVE_PENDING;
+	cpumask_clear(desc->pending_mask);
+
+unmask:
+	unmask_IO_APIC_irq_desc(desc);
+
+	return ret;
+}
+
+static void ir_irq_migration(struct work_struct *work)
+{
+	unsigned int irq;
+	struct irq_desc *desc;
+
+	for_each_irq_desc(irq, desc) {
+		if (desc->status & IRQ_MOVE_PENDING) {
+			unsigned long flags;
+
+			spin_lock_irqsave(&desc->lock, flags);
+			if (!desc->chip->set_affinity ||
+			    !(desc->status & IRQ_MOVE_PENDING)) {
+				desc->status &= ~IRQ_MOVE_PENDING;
+				spin_unlock_irqrestore(&desc->lock, flags);
+				continue;
+			}
+
+			desc->chip->set_affinity(irq, desc->pending_mask);
+			spin_unlock_irqrestore(&desc->lock, flags);
+		}
+	}
+}
+
+/*
+ * Migrates the IRQ destination in the process context.
+ */
+static void set_ir_ioapic_affinity_irq_desc(struct irq_desc *desc,
+					    const struct cpumask *mask)
+{
+	if (desc->status & IRQ_LEVEL) {
+		desc->status |= IRQ_MOVE_PENDING;
+		cpumask_copy(desc->pending_mask, mask);
+		migrate_irq_remapped_level_desc(desc);
+		return;
+	}
+
+	migrate_ioapic_irq_desc(desc, mask);
+}
+static void set_ir_ioapic_affinity_irq(unsigned int irq,
+				       const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	set_ir_ioapic_affinity_irq_desc(desc, mask);
+}
+#endif
+
+asmlinkage void smp_irq_move_cleanup_interrupt(void)
+{
+	unsigned vector, me;
+
+	ack_APIC_irq();
+	exit_idle();
+	irq_enter();
+
+	me = smp_processor_id();
+	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
+		unsigned int irq;
+		struct irq_desc *desc;
+		struct irq_cfg *cfg;
+		irq = __get_cpu_var(vector_irq)[vector];
+
+		if (irq == -1)
+			continue;
+
+		desc = irq_to_desc(irq);
+		if (!desc)
+			continue;
+
+		cfg = irq_cfg(irq);
+		spin_lock(&desc->lock);
+		if (!cfg->move_cleanup_count)
+			goto unlock;
+
+		if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain))
+			goto unlock;
+
+		__get_cpu_var(vector_irq)[vector] = -1;
+		cfg->move_cleanup_count--;
+unlock:
+		spin_unlock(&desc->lock);
+	}
+
+	irq_exit();
+}
+
+static void irq_complete_move(struct irq_desc **descp)
+{
+	struct irq_desc *desc = *descp;
+	struct irq_cfg *cfg = desc->chip_data;
+	unsigned vector, me;
+
+	if (likely(!cfg->move_in_progress)) {
+#ifdef CONFIG_NUMA_MIGRATE_IRQ_DESC
+		if (likely(!cfg->move_desc_pending))
+			return;
+
+		/* domain has not changed, but affinity did */
+		me = smp_processor_id();
+		if (cpumask_test_cpu(me, desc->affinity)) {
+			*descp = desc = move_irq_desc(desc, me);
+			/* get the new one */
+			cfg = desc->chip_data;
+			cfg->move_desc_pending = 0;
+		}
+#endif
+		return;
+	}
+
+	vector = ~get_irq_regs()->orig_ax;
+	me = smp_processor_id();
+
+	if (vector == cfg->vector && cpumask_test_cpu(me, cfg->domain)) {
+#ifdef CONFIG_NUMA_MIGRATE_IRQ_DESC
+		*descp = desc = move_irq_desc(desc, me);
+		/* get the new one */
+		cfg = desc->chip_data;
+#endif
+		send_cleanup_vector(cfg);
+	}
+}
+#else
+static inline void irq_complete_move(struct irq_desc **descp) {}
+#endif
+
+#ifdef CONFIG_INTR_REMAP
+static void ack_x2apic_level(unsigned int irq)
+{
+	ack_x2APIC_irq();
+}
+
+static void ack_x2apic_edge(unsigned int irq)
+{
+	ack_x2APIC_irq();
+}
+
+#endif
+
+static void ack_apic_edge(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	irq_complete_move(&desc);
+	move_native_irq(irq);
+	ack_APIC_irq();
+}
+
+atomic_t irq_mis_count;
+
+static void ack_apic_level(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+#ifdef CONFIG_X86_32
+	unsigned long v;
+	int i;
+#endif
+	struct irq_cfg *cfg;
+	int do_unmask_irq = 0;
+
+	irq_complete_move(&desc);
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+	/* If we are moving the irq we need to mask it */
+	if (unlikely(desc->status & IRQ_MOVE_PENDING)) {
+		do_unmask_irq = 1;
+		mask_IO_APIC_irq_desc(desc);
+	}
+#endif
+
+#ifdef CONFIG_X86_32
+	/*
+	* It appears there is an erratum which affects at least version 0x11
+	* of I/O APIC (that's the 82093AA and cores integrated into various
+	* chipsets).  Under certain conditions a level-triggered interrupt is
+	* erroneously delivered as edge-triggered one but the respective IRR
+	* bit gets set nevertheless.  As a result the I/O unit expects an EOI
+	* message but it will never arrive and further interrupts are blocked
+	* from the source.  The exact reason is so far unknown, but the
+	* phenomenon was observed when two consecutive interrupt requests
+	* from a given source get delivered to the same CPU and the source is
+	* temporarily disabled in between.
+	*
+	* A workaround is to simulate an EOI message manually.  We achieve it
+	* by setting the trigger mode to edge and then to level when the edge
+	* trigger mode gets detected in the TMR of a local APIC for a
+	* level-triggered interrupt.  We mask the source for the time of the
+	* operation to prevent an edge-triggered interrupt escaping meanwhile.
+	* The idea is from Manfred Spraul.  --macro
+	*/
+	cfg = desc->chip_data;
+	i = cfg->vector;
+
+	v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
+#endif
+
+	/*
+	 * We must acknowledge the irq before we move it or the acknowledge will
+	 * not propagate properly.
+	 */
+	ack_APIC_irq();
+
+	/* Now we can move and renable the irq */
+	if (unlikely(do_unmask_irq)) {
+		/* Only migrate the irq if the ack has been received.
+		 *
+		 * On rare occasions the broadcast level triggered ack gets
+		 * delayed going to ioapics, and if we reprogram the
+		 * vector while Remote IRR is still set the irq will never
+		 * fire again.
+		 *
+		 * To prevent this scenario we read the Remote IRR bit
+		 * of the ioapic.  This has two effects.
+		 * - On any sane system the read of the ioapic will
+		 *   flush writes (and acks) going to the ioapic from
+		 *   this cpu.
+		 * - We get to see if the ACK has actually been delivered.
+		 *
+		 * Based on failed experiments of reprogramming the
+		 * ioapic entry from outside of irq context starting
+		 * with masking the ioapic entry and then polling until
+		 * Remote IRR was clear before reprogramming the
+		 * ioapic I don't trust the Remote IRR bit to be
+		 * completey accurate.
+		 *
+		 * However there appears to be no other way to plug
+		 * this race, so if the Remote IRR bit is not
+		 * accurate and is causing problems then it is a hardware bug
+		 * and you can go talk to the chipset vendor about it.
+		 */
+		cfg = desc->chip_data;
+		if (!io_apic_level_ack_pending(cfg))
+			move_masked_irq(irq);
+		unmask_IO_APIC_irq_desc(desc);
+	}
+
+#ifdef CONFIG_X86_32
+	if (!(v & (1 << (i & 0x1f)))) {
+		atomic_inc(&irq_mis_count);
+		spin_lock(&ioapic_lock);
+		__mask_and_edge_IO_APIC_irq(cfg);
+		__unmask_and_level_IO_APIC_irq(cfg);
+		spin_unlock(&ioapic_lock);
+	}
+#endif
+}
+
+static struct irq_chip ioapic_chip __read_mostly = {
+	.name		= "IO-APIC",
+	.startup	= startup_ioapic_irq,
+	.mask		= mask_IO_APIC_irq,
+	.unmask		= unmask_IO_APIC_irq,
+	.ack		= ack_apic_edge,
+	.eoi		= ack_apic_level,
+#ifdef CONFIG_SMP
+	.set_affinity	= set_ioapic_affinity_irq,
+#endif
+	.retrigger	= ioapic_retrigger_irq,
+};
+
+#ifdef CONFIG_INTR_REMAP
+static struct irq_chip ir_ioapic_chip __read_mostly = {
+	.name		= "IR-IO-APIC",
+	.startup	= startup_ioapic_irq,
+	.mask		= mask_IO_APIC_irq,
+	.unmask		= unmask_IO_APIC_irq,
+	.ack		= ack_x2apic_edge,
+	.eoi		= ack_x2apic_level,
+#ifdef CONFIG_SMP
+	.set_affinity	= set_ir_ioapic_affinity_irq,
+#endif
+	.retrigger	= ioapic_retrigger_irq,
+};
+#endif
+
+static inline void init_IO_APIC_traps(void)
+{
+	int irq;
+	struct irq_desc *desc;
+	struct irq_cfg *cfg;
+
+	/*
+	 * NOTE! The local APIC isn't very good at handling
+	 * multiple interrupts at the same interrupt level.
+	 * As the interrupt level is determined by taking the
+	 * vector number and shifting that right by 4, we
+	 * want to spread these out a bit so that they don't
+	 * all fall in the same interrupt level.
+	 *
+	 * Also, we've got to be careful not to trash gate
+	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
+	 */
+	for_each_irq_desc(irq, desc) {
+		cfg = desc->chip_data;
+		if (IO_APIC_IRQ(irq) && cfg && !cfg->vector) {
+			/*
+			 * Hmm.. We don't have an entry for this,
+			 * so default to an old-fashioned 8259
+			 * interrupt if we can..
+			 */
+			if (irq < NR_IRQS_LEGACY)
+				make_8259A_irq(irq);
+			else
+				/* Strange. Oh, well.. */
+				desc->chip = &no_irq_chip;
+		}
+	}
+}
+
+/*
+ * The local APIC irq-chip implementation:
+ */
+
+static void mask_lapic_irq(unsigned int irq)
+{
+	unsigned long v;
+
+	v = apic_read(APIC_LVT0);
+	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
+}
+
+static void unmask_lapic_irq(unsigned int irq)
+{
+	unsigned long v;
+
+	v = apic_read(APIC_LVT0);
+	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
+}
+
+static void ack_lapic_irq(unsigned int irq)
+{
+	ack_APIC_irq();
+}
+
+static struct irq_chip lapic_chip __read_mostly = {
+	.name		= "local-APIC",
+	.mask		= mask_lapic_irq,
+	.unmask		= unmask_lapic_irq,
+	.ack		= ack_lapic_irq,
+};
+
+static void lapic_register_intr(int irq, struct irq_desc *desc)
+{
+	desc->status &= ~IRQ_LEVEL;
+	set_irq_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,
+				      "edge");
+}
+
+static void __init setup_nmi(void)
+{
+	/*
+	 * Dirty trick to enable the NMI watchdog ...
+	 * We put the 8259A master into AEOI mode and
+	 * unmask on all local APICs LVT0 as NMI.
+	 *
+	 * The idea to use the 8259A in AEOI mode ('8259A Virtual Wire')
+	 * is from Maciej W. Rozycki - so we do not have to EOI from
+	 * the NMI handler or the timer interrupt.
+	 */
+	apic_printk(APIC_VERBOSE, KERN_INFO "activating NMI Watchdog ...");
+
+	enable_NMI_through_LVT0();
+
+	apic_printk(APIC_VERBOSE, " done.\n");
+}
+
+/*
+ * This looks a bit hackish but it's about the only one way of sending
+ * a few INTA cycles to 8259As and any associated glue logic.  ICR does
+ * not support the ExtINT mode, unfortunately.  We need to send these
+ * cycles as some i82489DX-based boards have glue logic that keeps the
+ * 8259A interrupt line asserted until INTA.  --macro
+ */
+static inline void __init unlock_ExtINT_logic(void)
+{
+	int apic, pin, i;
+	struct IO_APIC_route_entry entry0, entry1;
+	unsigned char save_control, save_freq_select;
+
+	pin  = find_isa_irq_pin(8, mp_INT);
+	if (pin == -1) {
+		WARN_ON_ONCE(1);
+		return;
+	}
+	apic = find_isa_irq_apic(8, mp_INT);
+	if (apic == -1) {
+		WARN_ON_ONCE(1);
+		return;
+	}
+
+	entry0 = ioapic_read_entry(apic, pin);
+	clear_IO_APIC_pin(apic, pin);
+
+	memset(&entry1, 0, sizeof(entry1));
+
+	entry1.dest_mode = 0;			/* physical delivery */
+	entry1.mask = 0;			/* unmask IRQ now */
+	entry1.dest = hard_smp_processor_id();
+	entry1.delivery_mode = dest_ExtINT;
+	entry1.polarity = entry0.polarity;
+	entry1.trigger = 0;
+	entry1.vector = 0;
+
+	ioapic_write_entry(apic, pin, entry1);
+
+	save_control = CMOS_READ(RTC_CONTROL);
+	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
+	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
+		   RTC_FREQ_SELECT);
+	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);
+
+	i = 100;
+	while (i-- > 0) {
+		mdelay(10);
+		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
+			i -= 10;
+	}
+
+	CMOS_WRITE(save_control, RTC_CONTROL);
+	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
+	clear_IO_APIC_pin(apic, pin);
+
+	ioapic_write_entry(apic, pin, entry0);
+}
+
+static int disable_timer_pin_1 __initdata;
+/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
+static int __init disable_timer_pin_setup(char *arg)
+{
+	disable_timer_pin_1 = 1;
+	return 0;
+}
+early_param("disable_timer_pin_1", disable_timer_pin_setup);
+
+int timer_through_8259 __initdata;
+
+/*
+ * This code may look a bit paranoid, but it's supposed to cooperate with
+ * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
+ * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
+ * fanatically on his truly buggy board.
+ *
+ * FIXME: really need to revamp this for all platforms.
+ */
+static inline void __init check_timer(void)
+{
+	struct irq_desc *desc = irq_to_desc(0);
+	struct irq_cfg *cfg = desc->chip_data;
+	int cpu = boot_cpu_id;
+	int apic1, pin1, apic2, pin2;
+	unsigned long flags;
+	int no_pin1 = 0;
+
+	local_irq_save(flags);
+
+	/*
+	 * get/set the timer IRQ vector:
+	 */
+	disable_8259A_irq(0);
+	assign_irq_vector(0, cfg, apic->target_cpus());
+
+	/*
+	 * As IRQ0 is to be enabled in the 8259A, the virtual
+	 * wire has to be disabled in the local APIC.  Also
+	 * timer interrupts need to be acknowledged manually in
+	 * the 8259A for the i82489DX when using the NMI
+	 * watchdog as that APIC treats NMIs as level-triggered.
+	 * The AEOI mode will finish them in the 8259A
+	 * automatically.
+	 */
+	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
+	init_8259A(1);
+#ifdef CONFIG_X86_32
+	{
+		unsigned int ver;
+
+		ver = apic_read(APIC_LVR);
+		ver = GET_APIC_VERSION(ver);
+		timer_ack = (nmi_watchdog == NMI_IO_APIC && !APIC_INTEGRATED(ver));
+	}
+#endif
+
+	pin1  = find_isa_irq_pin(0, mp_INT);
+	apic1 = find_isa_irq_apic(0, mp_INT);
+	pin2  = ioapic_i8259.pin;
+	apic2 = ioapic_i8259.apic;
+
+	apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X "
+		    "apic1=%d pin1=%d apic2=%d pin2=%d\n",
+		    cfg->vector, apic1, pin1, apic2, pin2);
+
+	/*
+	 * Some BIOS writers are clueless and report the ExtINTA
+	 * I/O APIC input from the cascaded 8259A as the timer
+	 * interrupt input.  So just in case, if only one pin
+	 * was found above, try it both directly and through the
+	 * 8259A.
+	 */
+	if (pin1 == -1) {
+#ifdef CONFIG_INTR_REMAP
+		if (intr_remapping_enabled)
+			panic("BIOS bug: timer not connected to IO-APIC");
+#endif
+		pin1 = pin2;
+		apic1 = apic2;
+		no_pin1 = 1;
+	} else if (pin2 == -1) {
+		pin2 = pin1;
+		apic2 = apic1;
+	}
+
+	if (pin1 != -1) {
+		/*
+		 * Ok, does IRQ0 through the IOAPIC work?
+		 */
+		if (no_pin1) {
+			add_pin_to_irq_cpu(cfg, cpu, apic1, pin1);
+			setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
+		} else {
+			/* for edge trigger, setup_IO_APIC_irq already
+			 * leave it unmasked.
+			 * so only need to unmask if it is level-trigger
+			 * do we really have level trigger timer?
+			 */
+			int idx;
+			idx = find_irq_entry(apic1, pin1, mp_INT);
+			if (idx != -1 && irq_trigger(idx))
+				unmask_IO_APIC_irq_desc(desc);
+		}
+		if (timer_irq_works()) {
+			if (nmi_watchdog == NMI_IO_APIC) {
+				setup_nmi();
+				enable_8259A_irq(0);
+			}
+			if (disable_timer_pin_1 > 0)
+				clear_IO_APIC_pin(0, pin1);
+			goto out;
+		}
+#ifdef CONFIG_INTR_REMAP
+		if (intr_remapping_enabled)
+			panic("timer doesn't work through Interrupt-remapped IO-APIC");
+#endif
+		local_irq_disable();
+		clear_IO_APIC_pin(apic1, pin1);
+		if (!no_pin1)
+			apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: "
+				    "8254 timer not connected to IO-APIC\n");
+
+		apic_printk(APIC_QUIET, KERN_INFO "...trying to set up timer "
+			    "(IRQ0) through the 8259A ...\n");
+		apic_printk(APIC_QUIET, KERN_INFO
+			    "..... (found apic %d pin %d) ...\n", apic2, pin2);
+		/*
+		 * legacy devices should be connected to IO APIC #0
+		 */
+		replace_pin_at_irq_cpu(cfg, cpu, apic1, pin1, apic2, pin2);
+		setup_timer_IRQ0_pin(apic2, pin2, cfg->vector);
+		enable_8259A_irq(0);
+		if (timer_irq_works()) {
+			apic_printk(APIC_QUIET, KERN_INFO "....... works.\n");
+			timer_through_8259 = 1;
+			if (nmi_watchdog == NMI_IO_APIC) {
+				disable_8259A_irq(0);
+				setup_nmi();
+				enable_8259A_irq(0);
+			}
+			goto out;
+		}
+		/*
+		 * Cleanup, just in case ...
+		 */
+		local_irq_disable();
+		disable_8259A_irq(0);
+		clear_IO_APIC_pin(apic2, pin2);
+		apic_printk(APIC_QUIET, KERN_INFO "....... failed.\n");
+	}
+
+	if (nmi_watchdog == NMI_IO_APIC) {
+		apic_printk(APIC_QUIET, KERN_WARNING "timer doesn't work "
+			    "through the IO-APIC - disabling NMI Watchdog!\n");
+		nmi_watchdog = NMI_NONE;
+	}
+#ifdef CONFIG_X86_32
+	timer_ack = 0;
+#endif
+
+	apic_printk(APIC_QUIET, KERN_INFO
+		    "...trying to set up timer as Virtual Wire IRQ...\n");
+
+	lapic_register_intr(0, desc);
+	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */
+	enable_8259A_irq(0);
+
+	if (timer_irq_works()) {
+		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
+		goto out;
+	}
+	local_irq_disable();
+	disable_8259A_irq(0);
+	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
+	apic_printk(APIC_QUIET, KERN_INFO "..... failed.\n");
+
+	apic_printk(APIC_QUIET, KERN_INFO
+		    "...trying to set up timer as ExtINT IRQ...\n");
+
+	init_8259A(0);
+	make_8259A_irq(0);
+	apic_write(APIC_LVT0, APIC_DM_EXTINT);
+
+	unlock_ExtINT_logic();
+
+	if (timer_irq_works()) {
+		apic_printk(APIC_QUIET, KERN_INFO "..... works.\n");
+		goto out;
+	}
+	local_irq_disable();
+	apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n");
+	panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
+		"report.  Then try booting with the 'noapic' option.\n");
+out:
+	local_irq_restore(flags);
+}
+
+/*
+ * Traditionally ISA IRQ2 is the cascade IRQ, and is not available
+ * to devices.  However there may be an I/O APIC pin available for
+ * this interrupt regardless.  The pin may be left unconnected, but
+ * typically it will be reused as an ExtINT cascade interrupt for
+ * the master 8259A.  In the MPS case such a pin will normally be
+ * reported as an ExtINT interrupt in the MP table.  With ACPI
+ * there is no provision for ExtINT interrupts, and in the absence
+ * of an override it would be treated as an ordinary ISA I/O APIC
+ * interrupt, that is edge-triggered and unmasked by default.  We
+ * used to do this, but it caused problems on some systems because
+ * of the NMI watchdog and sometimes IRQ0 of the 8254 timer using
+ * the same ExtINT cascade interrupt to drive the local APIC of the
+ * bootstrap processor.  Therefore we refrain from routing IRQ2 to
+ * the I/O APIC in all cases now.  No actual device should request
+ * it anyway.  --macro
+ */
+#define PIC_IRQS	(1 << PIC_CASCADE_IR)
+
+void __init setup_IO_APIC(void)
+{
+
+	/*
+	 * calling enable_IO_APIC() is moved to setup_local_APIC for BP
+	 */
+
+	io_apic_irqs = ~PIC_IRQS;
+
+	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
+	/*
+         * Set up IO-APIC IRQ routing.
+         */
+#ifdef CONFIG_X86_32
+	if (!acpi_ioapic)
+		setup_ioapic_ids_from_mpc();
+#endif
+	sync_Arb_IDs();
+	setup_IO_APIC_irqs();
+	init_IO_APIC_traps();
+	check_timer();
+}
+
+/*
+ *      Called after all the initialization is done. If we didnt find any
+ *      APIC bugs then we can allow the modify fast path
+ */
+
+static int __init io_apic_bug_finalize(void)
+{
+	if (sis_apic_bug == -1)
+		sis_apic_bug = 0;
+	return 0;
+}
+
+late_initcall(io_apic_bug_finalize);
+
+struct sysfs_ioapic_data {
+	struct sys_device dev;
+	struct IO_APIC_route_entry entry[0];
+};
+static struct sysfs_ioapic_data * mp_ioapic_data[MAX_IO_APICS];
+
+static int ioapic_suspend(struct sys_device *dev, pm_message_t state)
+{
+	struct IO_APIC_route_entry *entry;
+	struct sysfs_ioapic_data *data;
+	int i;
+
+	data = container_of(dev, struct sysfs_ioapic_data, dev);
+	entry = data->entry;
+	for (i = 0; i < nr_ioapic_registers[dev->id]; i ++, entry ++ )
+		*entry = ioapic_read_entry(dev->id, i);
+
+	return 0;
+}
+
+static int ioapic_resume(struct sys_device *dev)
+{
+	struct IO_APIC_route_entry *entry;
+	struct sysfs_ioapic_data *data;
+	unsigned long flags;
+	union IO_APIC_reg_00 reg_00;
+	int i;
+
+	data = container_of(dev, struct sysfs_ioapic_data, dev);
+	entry = data->entry;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_00.raw = io_apic_read(dev->id, 0);
+	if (reg_00.bits.ID != mp_ioapics[dev->id].apicid) {
+		reg_00.bits.ID = mp_ioapics[dev->id].apicid;
+		io_apic_write(dev->id, 0, reg_00.raw);
+	}
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+	for (i = 0; i < nr_ioapic_registers[dev->id]; i++)
+		ioapic_write_entry(dev->id, i, entry[i]);
+
+	return 0;
+}
+
+static struct sysdev_class ioapic_sysdev_class = {
+	.name = "ioapic",
+	.suspend = ioapic_suspend,
+	.resume = ioapic_resume,
+};
+
+static int __init ioapic_init_sysfs(void)
+{
+	struct sys_device * dev;
+	int i, size, error;
+
+	error = sysdev_class_register(&ioapic_sysdev_class);
+	if (error)
+		return error;
+
+	for (i = 0; i < nr_ioapics; i++ ) {
+		size = sizeof(struct sys_device) + nr_ioapic_registers[i]
+			* sizeof(struct IO_APIC_route_entry);
+		mp_ioapic_data[i] = kzalloc(size, GFP_KERNEL);
+		if (!mp_ioapic_data[i]) {
+			printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
+			continue;
+		}
+		dev = &mp_ioapic_data[i]->dev;
+		dev->id = i;
+		dev->cls = &ioapic_sysdev_class;
+		error = sysdev_register(dev);
+		if (error) {
+			kfree(mp_ioapic_data[i]);
+			mp_ioapic_data[i] = NULL;
+			printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
+			continue;
+		}
+	}
+
+	return 0;
+}
+
+device_initcall(ioapic_init_sysfs);
+
+static int nr_irqs_gsi = NR_IRQS_LEGACY;
+/*
+ * Dynamic irq allocate and deallocation
+ */
+unsigned int create_irq_nr(unsigned int irq_want)
+{
+	/* Allocate an unused irq */
+	unsigned int irq;
+	unsigned int new;
+	unsigned long flags;
+	struct irq_cfg *cfg_new = NULL;
+	int cpu = boot_cpu_id;
+	struct irq_desc *desc_new = NULL;
+
+	irq = 0;
+	if (irq_want < nr_irqs_gsi)
+		irq_want = nr_irqs_gsi;
+
+	spin_lock_irqsave(&vector_lock, flags);
+	for (new = irq_want; new < nr_irqs; new++) {
+		desc_new = irq_to_desc_alloc_cpu(new, cpu);
+		if (!desc_new) {
+			printk(KERN_INFO "can not get irq_desc for %d\n", new);
+			continue;
+		}
+		cfg_new = desc_new->chip_data;
+
+		if (cfg_new->vector != 0)
+			continue;
+		if (__assign_irq_vector(new, cfg_new, apic->target_cpus()) == 0)
+			irq = new;
+		break;
+	}
+	spin_unlock_irqrestore(&vector_lock, flags);
+
+	if (irq > 0) {
+		dynamic_irq_init(irq);
+		/* restore it, in case dynamic_irq_init clear it */
+		if (desc_new)
+			desc_new->chip_data = cfg_new;
+	}
+	return irq;
+}
+
+int create_irq(void)
+{
+	unsigned int irq_want;
+	int irq;
+
+	irq_want = nr_irqs_gsi;
+	irq = create_irq_nr(irq_want);
+
+	if (irq == 0)
+		irq = -1;
+
+	return irq;
+}
+
+void destroy_irq(unsigned int irq)
+{
+	unsigned long flags;
+	struct irq_cfg *cfg;
+	struct irq_desc *desc;
+
+	/* store it, in case dynamic_irq_cleanup clear it */
+	desc = irq_to_desc(irq);
+	cfg = desc->chip_data;
+	dynamic_irq_cleanup(irq);
+	/* connect back irq_cfg */
+	if (desc)
+		desc->chip_data = cfg;
+
+#ifdef CONFIG_INTR_REMAP
+	free_irte(irq);
+#endif
+	spin_lock_irqsave(&vector_lock, flags);
+	__clear_irq_vector(irq, cfg);
+	spin_unlock_irqrestore(&vector_lock, flags);
+}
+
+/*
+ * MSI message composition
+ */
+#ifdef CONFIG_PCI_MSI
+static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq, struct msi_msg *msg)
+{
+	struct irq_cfg *cfg;
+	int err;
+	unsigned dest;
+
+	if (disable_apic)
+		return -ENXIO;
+
+	cfg = irq_cfg(irq);
+	err = assign_irq_vector(irq, cfg, apic->target_cpus());
+	if (err)
+		return err;
+
+	dest = apic->cpu_mask_to_apicid_and(cfg->domain, apic->target_cpus());
+
+#ifdef CONFIG_INTR_REMAP
+	if (irq_remapped(irq)) {
+		struct irte irte;
+		int ir_index;
+		u16 sub_handle;
+
+		ir_index = map_irq_to_irte_handle(irq, &sub_handle);
+		BUG_ON(ir_index == -1);
+
+		memset (&irte, 0, sizeof(irte));
+
+		irte.present = 1;
+		irte.dst_mode = apic->irq_dest_mode;
+		irte.trigger_mode = 0; /* edge */
+		irte.dlvry_mode = apic->irq_delivery_mode;
+		irte.vector = cfg->vector;
+		irte.dest_id = IRTE_DEST(dest);
+
+		modify_irte(irq, &irte);
+
+		msg->address_hi = MSI_ADDR_BASE_HI;
+		msg->data = sub_handle;
+		msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_IR_EXT_INT |
+				  MSI_ADDR_IR_SHV |
+				  MSI_ADDR_IR_INDEX1(ir_index) |
+				  MSI_ADDR_IR_INDEX2(ir_index);
+	} else
+#endif
+	{
+		msg->address_hi = MSI_ADDR_BASE_HI;
+		msg->address_lo =
+			MSI_ADDR_BASE_LO |
+			((apic->irq_dest_mode == 0) ?
+				MSI_ADDR_DEST_MODE_PHYSICAL:
+				MSI_ADDR_DEST_MODE_LOGICAL) |
+			((apic->irq_delivery_mode != dest_LowestPrio) ?
+				MSI_ADDR_REDIRECTION_CPU:
+				MSI_ADDR_REDIRECTION_LOWPRI) |
+			MSI_ADDR_DEST_ID(dest);
+
+		msg->data =
+			MSI_DATA_TRIGGER_EDGE |
+			MSI_DATA_LEVEL_ASSERT |
+			((apic->irq_delivery_mode != dest_LowestPrio) ?
+				MSI_DATA_DELIVERY_FIXED:
+				MSI_DATA_DELIVERY_LOWPRI) |
+			MSI_DATA_VECTOR(cfg->vector);
+	}
+	return err;
+}
+
+#ifdef CONFIG_SMP
+static void set_msi_irq_affinity(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_cfg *cfg;
+	struct msi_msg msg;
+	unsigned int dest;
+
+	dest = set_desc_affinity(desc, mask);
+	if (dest == BAD_APICID)
+		return;
+
+	cfg = desc->chip_data;
+
+	read_msi_msg_desc(desc, &msg);
+
+	msg.data &= ~MSI_DATA_VECTOR_MASK;
+	msg.data |= MSI_DATA_VECTOR(cfg->vector);
+	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
+	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
+
+	write_msi_msg_desc(desc, &msg);
+}
+#ifdef CONFIG_INTR_REMAP
+/*
+ * Migrate the MSI irq to another cpumask. This migration is
+ * done in the process context using interrupt-remapping hardware.
+ */
+static void
+ir_set_msi_irq_affinity(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_cfg *cfg = desc->chip_data;
+	unsigned int dest;
+	struct irte irte;
+
+	if (get_irte(irq, &irte))
+		return;
+
+	dest = set_desc_affinity(desc, mask);
+	if (dest == BAD_APICID)
+		return;
+
+	irte.vector = cfg->vector;
+	irte.dest_id = IRTE_DEST(dest);
+
+	/*
+	 * atomically update the IRTE with the new destination and vector.
+	 */
+	modify_irte(irq, &irte);
+
+	/*
+	 * After this point, all the interrupts will start arriving
+	 * at the new destination. So, time to cleanup the previous
+	 * vector allocation.
+	 */
+	if (cfg->move_in_progress)
+		send_cleanup_vector(cfg);
+}
+
+#endif
+#endif /* CONFIG_SMP */
+
+/*
+ * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
+ * which implement the MSI or MSI-X Capability Structure.
+ */
+static struct irq_chip msi_chip = {
+	.name		= "PCI-MSI",
+	.unmask		= unmask_msi_irq,
+	.mask		= mask_msi_irq,
+	.ack		= ack_apic_edge,
+#ifdef CONFIG_SMP
+	.set_affinity	= set_msi_irq_affinity,
+#endif
+	.retrigger	= ioapic_retrigger_irq,
+};
+
+#ifdef CONFIG_INTR_REMAP
+static struct irq_chip msi_ir_chip = {
+	.name		= "IR-PCI-MSI",
+	.unmask		= unmask_msi_irq,
+	.mask		= mask_msi_irq,
+	.ack		= ack_x2apic_edge,
+#ifdef CONFIG_SMP
+	.set_affinity	= ir_set_msi_irq_affinity,
+#endif
+	.retrigger	= ioapic_retrigger_irq,
+};
+
+/*
+ * Map the PCI dev to the corresponding remapping hardware unit
+ * and allocate 'nvec' consecutive interrupt-remapping table entries
+ * in it.
+ */
+static int msi_alloc_irte(struct pci_dev *dev, int irq, int nvec)
+{
+	struct intel_iommu *iommu;
+	int index;
+
+	iommu = map_dev_to_ir(dev);
+	if (!iommu) {
+		printk(KERN_ERR
+		       "Unable to map PCI %s to iommu\n", pci_name(dev));
+		return -ENOENT;
+	}
+
+	index = alloc_irte(iommu, irq, nvec);
+	if (index < 0) {
+		printk(KERN_ERR
+		       "Unable to allocate %d IRTE for PCI %s\n", nvec,
+		       pci_name(dev));
+		return -ENOSPC;
+	}
+	return index;
+}
+#endif
+
+static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int irq)
+{
+	int ret;
+	struct msi_msg msg;
+
+	ret = msi_compose_msg(dev, irq, &msg);
+	if (ret < 0)
+		return ret;
+
+	set_irq_msi(irq, msidesc);
+	write_msi_msg(irq, &msg);
+
+#ifdef CONFIG_INTR_REMAP
+	if (irq_remapped(irq)) {
+		struct irq_desc *desc = irq_to_desc(irq);
+		/*
+		 * irq migration in process context
+		 */
+		desc->status |= IRQ_MOVE_PCNTXT;
+		set_irq_chip_and_handler_name(irq, &msi_ir_chip, handle_edge_irq, "edge");
+	} else
+#endif
+		set_irq_chip_and_handler_name(irq, &msi_chip, handle_edge_irq, "edge");
+
+	dev_printk(KERN_DEBUG, &dev->dev, "irq %d for MSI/MSI-X\n", irq);
+
+	return 0;
+}
+
+int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+	unsigned int irq;
+	int ret, sub_handle;
+	struct msi_desc *msidesc;
+	unsigned int irq_want;
+
+#ifdef CONFIG_INTR_REMAP
+	struct intel_iommu *iommu = 0;
+	int index = 0;
+#endif
+
+	irq_want = nr_irqs_gsi;
+	sub_handle = 0;
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+		irq = create_irq_nr(irq_want);
+		if (irq == 0)
+			return -1;
+		irq_want = irq + 1;
+#ifdef CONFIG_INTR_REMAP
+		if (!intr_remapping_enabled)
+			goto no_ir;
+
+		if (!sub_handle) {
+			/*
+			 * allocate the consecutive block of IRTE's
+			 * for 'nvec'
+			 */
+			index = msi_alloc_irte(dev, irq, nvec);
+			if (index < 0) {
+				ret = index;
+				goto error;
+			}
+		} else {
+			iommu = map_dev_to_ir(dev);
+			if (!iommu) {
+				ret = -ENOENT;
+				goto error;
+			}
+			/*
+			 * setup the mapping between the irq and the IRTE
+			 * base index, the sub_handle pointing to the
+			 * appropriate interrupt remap table entry.
+			 */
+			set_irte_irq(irq, iommu, index, sub_handle);
+		}
+no_ir:
+#endif
+		ret = setup_msi_irq(dev, msidesc, irq);
+		if (ret < 0)
+			goto error;
+		sub_handle++;
+	}
+	return 0;
+
+error:
+	destroy_irq(irq);
+	return ret;
+}
+
+void arch_teardown_msi_irq(unsigned int irq)
+{
+	destroy_irq(irq);
+}
+
+#ifdef CONFIG_DMAR
+#ifdef CONFIG_SMP
+static void dmar_msi_set_affinity(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_cfg *cfg;
+	struct msi_msg msg;
+	unsigned int dest;
+
+	dest = set_desc_affinity(desc, mask);
+	if (dest == BAD_APICID)
+		return;
+
+	cfg = desc->chip_data;
+
+	dmar_msi_read(irq, &msg);
+
+	msg.data &= ~MSI_DATA_VECTOR_MASK;
+	msg.data |= MSI_DATA_VECTOR(cfg->vector);
+	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
+	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
+
+	dmar_msi_write(irq, &msg);
+}
+
+#endif /* CONFIG_SMP */
+
+struct irq_chip dmar_msi_type = {
+	.name = "DMAR_MSI",
+	.unmask = dmar_msi_unmask,
+	.mask = dmar_msi_mask,
+	.ack = ack_apic_edge,
+#ifdef CONFIG_SMP
+	.set_affinity = dmar_msi_set_affinity,
+#endif
+	.retrigger = ioapic_retrigger_irq,
+};
+
+int arch_setup_dmar_msi(unsigned int irq)
+{
+	int ret;
+	struct msi_msg msg;
+
+	ret = msi_compose_msg(NULL, irq, &msg);
+	if (ret < 0)
+		return ret;
+	dmar_msi_write(irq, &msg);
+	set_irq_chip_and_handler_name(irq, &dmar_msi_type, handle_edge_irq,
+		"edge");
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_HPET_TIMER
+
+#ifdef CONFIG_SMP
+static void hpet_msi_set_affinity(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_cfg *cfg;
+	struct msi_msg msg;
+	unsigned int dest;
+
+	dest = set_desc_affinity(desc, mask);
+	if (dest == BAD_APICID)
+		return;
+
+	cfg = desc->chip_data;
+
+	hpet_msi_read(irq, &msg);
+
+	msg.data &= ~MSI_DATA_VECTOR_MASK;
+	msg.data |= MSI_DATA_VECTOR(cfg->vector);
+	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
+	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
+
+	hpet_msi_write(irq, &msg);
+}
+
+#endif /* CONFIG_SMP */
+
+struct irq_chip hpet_msi_type = {
+	.name = "HPET_MSI",
+	.unmask = hpet_msi_unmask,
+	.mask = hpet_msi_mask,
+	.ack = ack_apic_edge,
+#ifdef CONFIG_SMP
+	.set_affinity = hpet_msi_set_affinity,
+#endif
+	.retrigger = ioapic_retrigger_irq,
+};
+
+int arch_setup_hpet_msi(unsigned int irq)
+{
+	int ret;
+	struct msi_msg msg;
+
+	ret = msi_compose_msg(NULL, irq, &msg);
+	if (ret < 0)
+		return ret;
+
+	hpet_msi_write(irq, &msg);
+	set_irq_chip_and_handler_name(irq, &hpet_msi_type, handle_edge_irq,
+		"edge");
+
+	return 0;
+}
+#endif
+
+#endif /* CONFIG_PCI_MSI */
+/*
+ * Hypertransport interrupt support
+ */
+#ifdef CONFIG_HT_IRQ
+
+#ifdef CONFIG_SMP
+
+static void target_ht_irq(unsigned int irq, unsigned int dest, u8 vector)
+{
+	struct ht_irq_msg msg;
+	fetch_ht_irq_msg(irq, &msg);
+
+	msg.address_lo &= ~(HT_IRQ_LOW_VECTOR_MASK | HT_IRQ_LOW_DEST_ID_MASK);
+	msg.address_hi &= ~(HT_IRQ_HIGH_DEST_ID_MASK);
+
+	msg.address_lo |= HT_IRQ_LOW_VECTOR(vector) | HT_IRQ_LOW_DEST_ID(dest);
+	msg.address_hi |= HT_IRQ_HIGH_DEST_ID(dest);
+
+	write_ht_irq_msg(irq, &msg);
+}
+
+static void set_ht_irq_affinity(unsigned int irq, const struct cpumask *mask)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irq_cfg *cfg;
+	unsigned int dest;
+
+	dest = set_desc_affinity(desc, mask);
+	if (dest == BAD_APICID)
+		return;
+
+	cfg = desc->chip_data;
+
+	target_ht_irq(irq, dest, cfg->vector);
+}
+
+#endif
+
+static struct irq_chip ht_irq_chip = {
+	.name		= "PCI-HT",
+	.mask		= mask_ht_irq,
+	.unmask		= unmask_ht_irq,
+	.ack		= ack_apic_edge,
+#ifdef CONFIG_SMP
+	.set_affinity	= set_ht_irq_affinity,
+#endif
+	.retrigger	= ioapic_retrigger_irq,
+};
+
+int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
+{
+	struct irq_cfg *cfg;
+	int err;
+
+	if (disable_apic)
+		return -ENXIO;
+
+	cfg = irq_cfg(irq);
+	err = assign_irq_vector(irq, cfg, apic->target_cpus());
+	if (!err) {
+		struct ht_irq_msg msg;
+		unsigned dest;
+
+		dest = apic->cpu_mask_to_apicid_and(cfg->domain,
+						    apic->target_cpus());
+
+		msg.address_hi = HT_IRQ_HIGH_DEST_ID(dest);
+
+		msg.address_lo =
+			HT_IRQ_LOW_BASE |
+			HT_IRQ_LOW_DEST_ID(dest) |
+			HT_IRQ_LOW_VECTOR(cfg->vector) |
+			((apic->irq_dest_mode == 0) ?
+				HT_IRQ_LOW_DM_PHYSICAL :
+				HT_IRQ_LOW_DM_LOGICAL) |
+			HT_IRQ_LOW_RQEOI_EDGE |
+			((apic->irq_delivery_mode != dest_LowestPrio) ?
+				HT_IRQ_LOW_MT_FIXED :
+				HT_IRQ_LOW_MT_ARBITRATED) |
+			HT_IRQ_LOW_IRQ_MASKED;
+
+		write_ht_irq_msg(irq, &msg);
+
+		set_irq_chip_and_handler_name(irq, &ht_irq_chip,
+					      handle_edge_irq, "edge");
+
+		dev_printk(KERN_DEBUG, &dev->dev, "irq %d for HT\n", irq);
+	}
+	return err;
+}
+#endif /* CONFIG_HT_IRQ */
+
+#ifdef CONFIG_X86_UV
+/*
+ * Re-target the irq to the specified CPU and enable the specified MMR located
+ * on the specified blade to allow the sending of MSIs to the specified CPU.
+ */
+int arch_enable_uv_irq(char *irq_name, unsigned int irq, int cpu, int mmr_blade,
+		       unsigned long mmr_offset)
+{
+	const struct cpumask *eligible_cpu = cpumask_of(cpu);
+	struct irq_cfg *cfg;
+	int mmr_pnode;
+	unsigned long mmr_value;
+	struct uv_IO_APIC_route_entry *entry;
+	unsigned long flags;
+	int err;
+
+	cfg = irq_cfg(irq);
+
+	err = assign_irq_vector(irq, cfg, eligible_cpu);
+	if (err != 0)
+		return err;
+
+	spin_lock_irqsave(&vector_lock, flags);
+	set_irq_chip_and_handler_name(irq, &uv_irq_chip, handle_percpu_irq,
+				      irq_name);
+	spin_unlock_irqrestore(&vector_lock, flags);
+
+	mmr_value = 0;
+	entry = (struct uv_IO_APIC_route_entry *)&mmr_value;
+	BUG_ON(sizeof(struct uv_IO_APIC_route_entry) != sizeof(unsigned long));
+
+	entry->vector = cfg->vector;
+	entry->delivery_mode = apic->irq_delivery_mode;
+	entry->dest_mode = apic->irq_dest_mode;
+	entry->polarity = 0;
+	entry->trigger = 0;
+	entry->mask = 0;
+	entry->dest = apic->cpu_mask_to_apicid(eligible_cpu);
+
+	mmr_pnode = uv_blade_to_pnode(mmr_blade);
+	uv_write_global_mmr64(mmr_pnode, mmr_offset, mmr_value);
+
+	return irq;
+}
+
+/*
+ * Disable the specified MMR located on the specified blade so that MSIs are
+ * longer allowed to be sent.
+ */
+void arch_disable_uv_irq(int mmr_blade, unsigned long mmr_offset)
+{
+	unsigned long mmr_value;
+	struct uv_IO_APIC_route_entry *entry;
+	int mmr_pnode;
+
+	mmr_value = 0;
+	entry = (struct uv_IO_APIC_route_entry *)&mmr_value;
+	BUG_ON(sizeof(struct uv_IO_APIC_route_entry) != sizeof(unsigned long));
+
+	entry->mask = 1;
+
+	mmr_pnode = uv_blade_to_pnode(mmr_blade);
+	uv_write_global_mmr64(mmr_pnode, mmr_offset, mmr_value);
+}
+#endif /* CONFIG_X86_64 */
+
+int __init io_apic_get_redir_entries (int ioapic)
+{
+	union IO_APIC_reg_01	reg_01;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_01.raw = io_apic_read(ioapic, 1);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	return reg_01.bits.entries;
+}
+
+void __init probe_nr_irqs_gsi(void)
+{
+	int nr = 0;
+
+	nr = acpi_probe_gsi();
+	if (nr > nr_irqs_gsi) {
+		nr_irqs_gsi = nr;
+	} else {
+		/* for acpi=off or acpi is not compiled in */
+		int idx;
+
+		nr = 0;
+		for (idx = 0; idx < nr_ioapics; idx++)
+			nr += io_apic_get_redir_entries(idx) + 1;
+
+		if (nr > nr_irqs_gsi)
+			nr_irqs_gsi = nr;
+	}
+
+	printk(KERN_DEBUG "nr_irqs_gsi: %d\n", nr_irqs_gsi);
+}
+
+#ifdef CONFIG_SPARSE_IRQ
+int __init arch_probe_nr_irqs(void)
+{
+	int nr;
+
+	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
+		nr_irqs = NR_VECTORS * nr_cpu_ids;
+
+	nr = nr_irqs_gsi + 8 * nr_cpu_ids;
+#if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
+	/*
+	 * for MSI and HT dyn irq
+	 */
+	nr += nr_irqs_gsi * 16;
+#endif
+	if (nr < nr_irqs)
+		nr_irqs = nr;
+
+	return 0;
+}
+#endif
+
+/* --------------------------------------------------------------------------
+                          ACPI-based IOAPIC Configuration
+   -------------------------------------------------------------------------- */
+
+#ifdef CONFIG_ACPI
+
+#ifdef CONFIG_X86_32
+int __init io_apic_get_unique_id(int ioapic, int apic_id)
+{
+	union IO_APIC_reg_00 reg_00;
+	static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
+	physid_mask_t tmp;
+	unsigned long flags;
+	int i = 0;
+
+	/*
+	 * The P4 platform supports up to 256 APIC IDs on two separate APIC
+	 * buses (one for LAPICs, one for IOAPICs), where predecessors only
+	 * supports up to 16 on one shared APIC bus.
+	 *
+	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
+	 *      advantage of new APIC bus architecture.
+	 */
+
+	if (physids_empty(apic_id_map))
+		apic_id_map = apic->ioapic_phys_id_map(phys_cpu_present_map);
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_00.raw = io_apic_read(ioapic, 0);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	if (apic_id >= get_physical_broadcast()) {
+		printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
+			"%d\n", ioapic, apic_id, reg_00.bits.ID);
+		apic_id = reg_00.bits.ID;
+	}
+
+	/*
+	 * Every APIC in a system must have a unique ID or we get lots of nice
+	 * 'stuck on smp_invalidate_needed IPI wait' messages.
+	 */
+	if (apic->check_apicid_used(apic_id_map, apic_id)) {
+
+		for (i = 0; i < get_physical_broadcast(); i++) {
+			if (!apic->check_apicid_used(apic_id_map, i))
+				break;
+		}
+
+		if (i == get_physical_broadcast())
+			panic("Max apic_id exceeded!\n");
+
+		printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
+			"trying %d\n", ioapic, apic_id, i);
+
+		apic_id = i;
+	}
+
+	tmp = apic->apicid_to_cpu_present(apic_id);
+	physids_or(apic_id_map, apic_id_map, tmp);
+
+	if (reg_00.bits.ID != apic_id) {
+		reg_00.bits.ID = apic_id;
+
+		spin_lock_irqsave(&ioapic_lock, flags);
+		io_apic_write(ioapic, 0, reg_00.raw);
+		reg_00.raw = io_apic_read(ioapic, 0);
+		spin_unlock_irqrestore(&ioapic_lock, flags);
+
+		/* Sanity check */
+		if (reg_00.bits.ID != apic_id) {
+			printk("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
+			return -1;
+		}
+	}
+
+	apic_printk(APIC_VERBOSE, KERN_INFO
+			"IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);
+
+	return apic_id;
+}
+
+int __init io_apic_get_version(int ioapic)
+{
+	union IO_APIC_reg_01	reg_01;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioapic_lock, flags);
+	reg_01.raw = io_apic_read(ioapic, 1);
+	spin_unlock_irqrestore(&ioapic_lock, flags);
+
+	return reg_01.bits.version;
+}
+#endif
+
+int io_apic_set_pci_routing (int ioapic, int pin, int irq, int triggering, int polarity)
+{
+	struct irq_desc *desc;
+	struct irq_cfg *cfg;
+	int cpu = boot_cpu_id;
+
+	if (!IO_APIC_IRQ(irq)) {
+		apic_printk(APIC_QUIET,KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
+			ioapic);
+		return -EINVAL;
+	}
+
+	desc = irq_to_desc_alloc_cpu(irq, cpu);
+	if (!desc) {
+		printk(KERN_INFO "can not get irq_desc %d\n", irq);
+		return 0;
+	}
+
+	/*
+	 * IRQs < 16 are already in the irq_2_pin[] map
+	 */
+	if (irq >= NR_IRQS_LEGACY) {
+		cfg = desc->chip_data;
+		add_pin_to_irq_cpu(cfg, cpu, ioapic, pin);
+	}
+
+	setup_IO_APIC_irq(ioapic, pin, irq, desc, triggering, polarity);
+
+	return 0;
+}
+
+
+int acpi_get_override_irq(int bus_irq, int *trigger, int *polarity)
+{
+	int i;
+
+	if (skip_ioapic_setup)
+		return -1;
+
+	for (i = 0; i < mp_irq_entries; i++)
+		if (mp_irqs[i].irqtype == mp_INT &&
+		    mp_irqs[i].srcbusirq == bus_irq)
+			break;
+	if (i >= mp_irq_entries)
+		return -1;
+
+	*trigger = irq_trigger(i);
+	*polarity = irq_polarity(i);
+	return 0;
+}
+
+#endif /* CONFIG_ACPI */
+
+/*
+ * This function currently is only a helper for the i386 smp boot process where
+ * we need to reprogram the ioredtbls to cater for the cpus which have come online
+ * so mask in all cases should simply be apic->target_cpus()
+ */
+#ifdef CONFIG_SMP
+void __init setup_ioapic_dest(void)
+{
+	int pin, ioapic, irq, irq_entry;
+	struct irq_desc *desc;
+	struct irq_cfg *cfg;
+	const struct cpumask *mask;
+
+	if (skip_ioapic_setup == 1)
+		return;
+
+	for (ioapic = 0; ioapic < nr_ioapics; ioapic++) {
+		for (pin = 0; pin < nr_ioapic_registers[ioapic]; pin++) {
+			irq_entry = find_irq_entry(ioapic, pin, mp_INT);
+			if (irq_entry == -1)
+				continue;
+			irq = pin_2_irq(irq_entry, ioapic, pin);
+
+			/* setup_IO_APIC_irqs could fail to get vector for some device
+			 * when you have too many devices, because at that time only boot
+			 * cpu is online.
+			 */
+			desc = irq_to_desc(irq);
+			cfg = desc->chip_data;
+			if (!cfg->vector) {
+				setup_IO_APIC_irq(ioapic, pin, irq, desc,
+						  irq_trigger(irq_entry),
+						  irq_polarity(irq_entry));
+				continue;
+
+			}
+
+			/*
+			 * Honour affinities which have been set in early boot
+			 */
+			if (desc->status &
+			    (IRQ_NO_BALANCING | IRQ_AFFINITY_SET))
+				mask = desc->affinity;
+			else
+				mask = apic->target_cpus();
+
+#ifdef CONFIG_INTR_REMAP
+			if (intr_remapping_enabled)
+				set_ir_ioapic_affinity_irq_desc(desc, mask);
+			else
+#endif
+				set_ioapic_affinity_irq_desc(desc, mask);
+		}
+
+	}
+}
+#endif
+
+#define IOAPIC_RESOURCE_NAME_SIZE 11
+
+static struct resource *ioapic_resources;
+
+static struct resource * __init ioapic_setup_resources(void)
+{
+	unsigned long n;
+	struct resource *res;
+	char *mem;
+	int i;
+
+	if (nr_ioapics <= 0)
+		return NULL;
+
+	n = IOAPIC_RESOURCE_NAME_SIZE + sizeof(struct resource);
+	n *= nr_ioapics;
+
+	mem = alloc_bootmem(n);
+	res = (void *)mem;
+
+	if (mem != NULL) {
+		mem += sizeof(struct resource) * nr_ioapics;
+
+		for (i = 0; i < nr_ioapics; i++) {
+			res[i].name = mem;
+			res[i].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+			sprintf(mem,  "IOAPIC %u", i);
+			mem += IOAPIC_RESOURCE_NAME_SIZE;
+		}
+	}
+
+	ioapic_resources = res;
+
+	return res;
+}
+
+void __init ioapic_init_mappings(void)
+{
+	unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
+	struct resource *ioapic_res;
+	int i;
+
+	ioapic_res = ioapic_setup_resources();
+	for (i = 0; i < nr_ioapics; i++) {
+		if (smp_found_config) {
+			ioapic_phys = mp_ioapics[i].apicaddr;
+#ifdef CONFIG_X86_32
+			if (!ioapic_phys) {
+				printk(KERN_ERR
+				       "WARNING: bogus zero IO-APIC "
+				       "address found in MPTABLE, "
+				       "disabling IO/APIC support!\n");
+				smp_found_config = 0;
+				skip_ioapic_setup = 1;
+				goto fake_ioapic_page;
+			}
+#endif
+		} else {
+#ifdef CONFIG_X86_32
+fake_ioapic_page:
+#endif
+			ioapic_phys = (unsigned long)
+				alloc_bootmem_pages(PAGE_SIZE);
+			ioapic_phys = __pa(ioapic_phys);
+		}
+		set_fixmap_nocache(idx, ioapic_phys);
+		apic_printk(APIC_VERBOSE,
+			    "mapped IOAPIC to %08lx (%08lx)\n",
+			    __fix_to_virt(idx), ioapic_phys);
+		idx++;
+
+		if (ioapic_res != NULL) {
+			ioapic_res->start = ioapic_phys;
+			ioapic_res->end = ioapic_phys + (4 * 1024) - 1;
+			ioapic_res++;
+		}
+	}
+}
+
+static int __init ioapic_insert_resources(void)
+{
+	int i;
+	struct resource *r = ioapic_resources;
+
+	if (!r) {
+		printk(KERN_ERR
+		       "IO APIC resources could be not be allocated.\n");
+		return -1;
+	}
+
+	for (i = 0; i < nr_ioapics; i++) {
+		insert_resource(&iomem_resource, r);
+		r++;
+	}
+
+	return 0;
+}
+
+/* Insert the IO APIC resources after PCI initialization has occured to handle
+ * IO APICS that are mapped in on a BAR in PCI space. */
+late_initcall(ioapic_insert_resources);