Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
new file mode 100644
index 0000000..c15be5c
--- /dev/null
+++ b/arch/ia64/kernel/iosapic.c
@@ -0,0 +1,827 @@
+/*
+ * I/O SAPIC support.
+ *
+ * Copyright (C) 1999 Intel Corp.
+ * Copyright (C) 1999 Asit Mallick <asit.k.mallick@intel.com>
+ * Copyright (C) 2000-2002 J.I. Lee <jung-ik.lee@intel.com>
+ * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co.
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999,2000 Walt Drummond <drummond@valinux.com>
+ *
+ * 00/04/19	D. Mosberger	Rewritten to mirror more closely the x86 I/O APIC code.
+ *				In particular, we now have separate handlers for edge
+ *				and level triggered interrupts.
+ * 00/10/27	Asit Mallick, Goutham Rao <goutham.rao@intel.com> IRQ vector allocation
+ *				PCI to vector mapping, shared PCI interrupts.
+ * 00/10/27	D. Mosberger	Document things a bit more to make them more understandable.
+ *				Clean up much of the old IOSAPIC cruft.
+ * 01/07/27	J.I. Lee	PCI irq routing, Platform/Legacy interrupts and fixes for
+ *				ACPI S5(SoftOff) support.
+ * 02/01/23	J.I. Lee	iosapic pgm fixes for PCI irq routing from _PRT
+ * 02/01/07     E. Focht        <efocht@ess.nec.de> Redirectable interrupt vectors in
+ *                              iosapic_set_affinity(), initializations for
+ *                              /proc/irq/#/smp_affinity
+ * 02/04/02	P. Diefenbaugh	Cleaned up ACPI PCI IRQ routing.
+ * 02/04/18	J.I. Lee	bug fix in iosapic_init_pci_irq
+ * 02/04/30	J.I. Lee	bug fix in find_iosapic to fix ACPI PCI IRQ to IOSAPIC mapping
+ *				error
+ * 02/07/29	T. Kochi	Allocate interrupt vectors dynamically
+ * 02/08/04	T. Kochi	Cleaned up terminology (irq, global system interrupt, vector, etc.)
+ * 02/09/20	D. Mosberger	Simplified by taking advantage of ACPI's pci_irq code.
+ * 03/02/19	B. Helgaas	Make pcat_compat system-wide, not per-IOSAPIC.
+ *				Remove iosapic_address & gsi_base from external interfaces.
+ *				Rationalize __init/__devinit attributes.
+ * 04/12/04 Ashok Raj	<ashok.raj@intel.com> Intel Corporation 2004
+ *				Updated to work with irq migration necessary for CPU Hotplug
+ */
+/*
+ * Here is what the interrupt logic between a PCI device and the kernel looks like:
+ *
+ * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC, INTD).  The
+ *     device is uniquely identified by its bus--, and slot-number (the function
+ *     number does not matter here because all functions share the same interrupt
+ *     lines).
+ *
+ * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC controller.
+ *     Multiple interrupt lines may have to share the same IOSAPIC pin (if they're level
+ *     triggered and use the same polarity).  Each interrupt line has a unique Global
+ *     System Interrupt (GSI) number which can be calculated as the sum of the controller's
+ *     base GSI number and the IOSAPIC pin number to which the line connects.
+ *
+ * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the IOSAPIC pin
+ *     into the IA-64 interrupt vector.  This interrupt vector is then sent to the CPU.
+ *
+ * (4) The kernel recognizes an interrupt as an IRQ.  The IRQ interface is used as
+ *     architecture-independent interrupt handling mechanism in Linux.  As an
+ *     IRQ is a number, we have to have IA-64 interrupt vector number <-> IRQ number
+ *     mapping.  On smaller systems, we use one-to-one mapping between IA-64 vector and
+ *     IRQ.  A platform can implement platform_irq_to_vector(irq) and
+ *     platform_local_vector_to_irq(vector) APIs to differentiate the mapping.
+ *     Please see also include/asm-ia64/hw_irq.h for those APIs.
+ *
+ * To sum up, there are three levels of mappings involved:
+ *
+ *	PCI pin -> global system interrupt (GSI) -> IA-64 vector <-> IRQ
+ *
+ * Note: The term "IRQ" is loosely used everywhere in Linux kernel to describe interrupts.
+ * Now we use "IRQ" only for Linux IRQ's.  ISA IRQ (isa_irq) is the only exception in this
+ * source code.
+ */
+#include <linux/config.h>
+
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/string.h>
+
+#include <asm/delay.h>
+#include <asm/hw_irq.h>
+#include <asm/io.h>
+#include <asm/iosapic.h>
+#include <asm/machvec.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/system.h>
+
+
+#undef DEBUG_INTERRUPT_ROUTING
+
+#ifdef DEBUG_INTERRUPT_ROUTING
+#define DBG(fmt...)	printk(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+static DEFINE_SPINLOCK(iosapic_lock);
+
+/* These tables map IA-64 vectors to the IOSAPIC pin that generates this vector. */
+
+static struct iosapic_intr_info {
+	char __iomem	*addr;		/* base address of IOSAPIC */
+	u32		low32;		/* current value of low word of Redirection table entry */
+	unsigned int	gsi_base;	/* first GSI assigned to this IOSAPIC */
+	char		rte_index;	/* IOSAPIC RTE index (-1 => not an IOSAPIC interrupt) */
+	unsigned char	dmode	: 3;	/* delivery mode (see iosapic.h) */
+	unsigned char 	polarity: 1;	/* interrupt polarity (see iosapic.h) */
+	unsigned char	trigger	: 1;	/* trigger mode (see iosapic.h) */
+	int		refcnt;		/* reference counter */
+} iosapic_intr_info[IA64_NUM_VECTORS];
+
+static struct iosapic {
+	char __iomem	*addr;		/* base address of IOSAPIC */
+	unsigned int 	gsi_base;	/* first GSI assigned to this IOSAPIC */
+	unsigned short 	num_rte;	/* number of RTE in this IOSAPIC */
+#ifdef CONFIG_NUMA
+	unsigned short	node;		/* numa node association via pxm */
+#endif
+} iosapic_lists[NR_IOSAPICS];
+
+static int num_iosapic;
+
+static unsigned char pcat_compat __initdata;	/* 8259 compatibility flag */
+
+
+/*
+ * Find an IOSAPIC associated with a GSI
+ */
+static inline int
+find_iosapic (unsigned int gsi)
+{
+	int i;
+
+	for (i = 0; i < num_iosapic; i++) {
+		if ((unsigned) (gsi - iosapic_lists[i].gsi_base) < iosapic_lists[i].num_rte)
+			return i;
+	}
+
+	return -1;
+}
+
+static inline int
+_gsi_to_vector (unsigned int gsi)
+{
+	struct iosapic_intr_info *info;
+
+	for (info = iosapic_intr_info; info < iosapic_intr_info + IA64_NUM_VECTORS; ++info)
+		if (info->gsi_base + info->rte_index == gsi)
+			return info - iosapic_intr_info;
+	return -1;
+}
+
+/*
+ * Translate GSI number to the corresponding IA-64 interrupt vector.  If no
+ * entry exists, return -1.
+ */
+inline int
+gsi_to_vector (unsigned int gsi)
+{
+	return _gsi_to_vector(gsi);
+}
+
+int
+gsi_to_irq (unsigned int gsi)
+{
+	/*
+	 * XXX fix me: this assumes an identity mapping vetween IA-64 vector and Linux irq
+	 * numbers...
+	 */
+	return _gsi_to_vector(gsi);
+}
+
+static void
+set_rte (unsigned int vector, unsigned int dest, int mask)
+{
+	unsigned long pol, trigger, dmode;
+	u32 low32, high32;
+	char __iomem *addr;
+	int rte_index;
+	char redir;
+
+	DBG(KERN_DEBUG"IOSAPIC: routing vector %d to 0x%x\n", vector, dest);
+
+	rte_index = iosapic_intr_info[vector].rte_index;
+	if (rte_index < 0)
+		return;		/* not an IOSAPIC interrupt */
+
+	addr    = iosapic_intr_info[vector].addr;
+	pol     = iosapic_intr_info[vector].polarity;
+	trigger = iosapic_intr_info[vector].trigger;
+	dmode   = iosapic_intr_info[vector].dmode;
+	vector &= (~IA64_IRQ_REDIRECTED);
+
+	redir = (dmode == IOSAPIC_LOWEST_PRIORITY) ? 1 : 0;
+
+#ifdef CONFIG_SMP
+	{
+		unsigned int irq;
+
+		for (irq = 0; irq < NR_IRQS; ++irq)
+			if (irq_to_vector(irq) == vector) {
+				set_irq_affinity_info(irq, (int)(dest & 0xffff), redir);
+				break;
+			}
+	}
+#endif
+
+	low32 = ((pol << IOSAPIC_POLARITY_SHIFT) |
+		 (trigger << IOSAPIC_TRIGGER_SHIFT) |
+		 (dmode << IOSAPIC_DELIVERY_SHIFT) |
+		 ((mask ? 1 : 0) << IOSAPIC_MASK_SHIFT) |
+		 vector);
+
+	/* dest contains both id and eid */
+	high32 = (dest << IOSAPIC_DEST_SHIFT);
+
+	iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
+	iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+	iosapic_intr_info[vector].low32 = low32;
+}
+
+static void
+nop (unsigned int vector)
+{
+	/* do nothing... */
+}
+
+static void
+mask_irq (unsigned int irq)
+{
+	unsigned long flags;
+	char __iomem *addr;
+	u32 low32;
+	int rte_index;
+	ia64_vector vec = irq_to_vector(irq);
+
+	addr = iosapic_intr_info[vec].addr;
+	rte_index = iosapic_intr_info[vec].rte_index;
+
+	if (rte_index < 0)
+		return;			/* not an IOSAPIC interrupt! */
+
+	spin_lock_irqsave(&iosapic_lock, flags);
+	{
+		/* set only the mask bit */
+		low32 = iosapic_intr_info[vec].low32 |= IOSAPIC_MASK;
+		iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+	}
+	spin_unlock_irqrestore(&iosapic_lock, flags);
+}
+
+static void
+unmask_irq (unsigned int irq)
+{
+	unsigned long flags;
+	char __iomem *addr;
+	u32 low32;
+	int rte_index;
+	ia64_vector vec = irq_to_vector(irq);
+
+	addr = iosapic_intr_info[vec].addr;
+	rte_index = iosapic_intr_info[vec].rte_index;
+	if (rte_index < 0)
+		return;			/* not an IOSAPIC interrupt! */
+
+	spin_lock_irqsave(&iosapic_lock, flags);
+	{
+		low32 = iosapic_intr_info[vec].low32 &= ~IOSAPIC_MASK;
+		iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+	}
+	spin_unlock_irqrestore(&iosapic_lock, flags);
+}
+
+
+static void
+iosapic_set_affinity (unsigned int irq, cpumask_t mask)
+{
+#ifdef CONFIG_SMP
+	unsigned long flags;
+	u32 high32, low32;
+	int dest, rte_index;
+	char __iomem *addr;
+	int redir = (irq & IA64_IRQ_REDIRECTED) ? 1 : 0;
+	ia64_vector vec;
+
+	irq &= (~IA64_IRQ_REDIRECTED);
+	vec = irq_to_vector(irq);
+
+	if (cpus_empty(mask))
+		return;
+
+	dest = cpu_physical_id(first_cpu(mask));
+
+	rte_index = iosapic_intr_info[vec].rte_index;
+	addr = iosapic_intr_info[vec].addr;
+
+	if (rte_index < 0)
+		return;			/* not an IOSAPIC interrupt */
+
+	set_irq_affinity_info(irq, dest, redir);
+
+	/* dest contains both id and eid */
+	high32 = dest << IOSAPIC_DEST_SHIFT;
+
+	spin_lock_irqsave(&iosapic_lock, flags);
+	{
+		low32 = iosapic_intr_info[vec].low32 & ~(7 << IOSAPIC_DELIVERY_SHIFT);
+
+		if (redir)
+		        /* change delivery mode to lowest priority */
+			low32 |= (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
+		else
+		        /* change delivery mode to fixed */
+			low32 |= (IOSAPIC_FIXED << IOSAPIC_DELIVERY_SHIFT);
+
+		iosapic_intr_info[vec].low32 = low32;
+		iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
+		iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+	}
+	spin_unlock_irqrestore(&iosapic_lock, flags);
+#endif
+}
+
+/*
+ * Handlers for level-triggered interrupts.
+ */
+
+static unsigned int
+iosapic_startup_level_irq (unsigned int irq)
+{
+	unmask_irq(irq);
+	return 0;
+}
+
+static void
+iosapic_end_level_irq (unsigned int irq)
+{
+	ia64_vector vec = irq_to_vector(irq);
+
+	move_irq(irq);
+	iosapic_eoi(iosapic_intr_info[vec].addr, vec);
+}
+
+#define iosapic_shutdown_level_irq	mask_irq
+#define iosapic_enable_level_irq	unmask_irq
+#define iosapic_disable_level_irq	mask_irq
+#define iosapic_ack_level_irq		nop
+
+struct hw_interrupt_type irq_type_iosapic_level = {
+	.typename =	"IO-SAPIC-level",
+	.startup =	iosapic_startup_level_irq,
+	.shutdown =	iosapic_shutdown_level_irq,
+	.enable =	iosapic_enable_level_irq,
+	.disable =	iosapic_disable_level_irq,
+	.ack =		iosapic_ack_level_irq,
+	.end =		iosapic_end_level_irq,
+	.set_affinity =	iosapic_set_affinity
+};
+
+/*
+ * Handlers for edge-triggered interrupts.
+ */
+
+static unsigned int
+iosapic_startup_edge_irq (unsigned int irq)
+{
+	unmask_irq(irq);
+	/*
+	 * IOSAPIC simply drops interrupts pended while the
+	 * corresponding pin was masked, so we can't know if an
+	 * interrupt is pending already.  Let's hope not...
+	 */
+	return 0;
+}
+
+static void
+iosapic_ack_edge_irq (unsigned int irq)
+{
+	irq_desc_t *idesc = irq_descp(irq);
+
+	move_irq(irq);
+	/*
+	 * Once we have recorded IRQ_PENDING already, we can mask the
+	 * interrupt for real. This prevents IRQ storms from unhandled
+	 * devices.
+	 */
+	if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) == (IRQ_PENDING|IRQ_DISABLED))
+		mask_irq(irq);
+}
+
+#define iosapic_enable_edge_irq		unmask_irq
+#define iosapic_disable_edge_irq	nop
+#define iosapic_end_edge_irq		nop
+
+struct hw_interrupt_type irq_type_iosapic_edge = {
+	.typename =	"IO-SAPIC-edge",
+	.startup =	iosapic_startup_edge_irq,
+	.shutdown =	iosapic_disable_edge_irq,
+	.enable =	iosapic_enable_edge_irq,
+	.disable =	iosapic_disable_edge_irq,
+	.ack =		iosapic_ack_edge_irq,
+	.end =		iosapic_end_edge_irq,
+	.set_affinity =	iosapic_set_affinity
+};
+
+unsigned int
+iosapic_version (char __iomem *addr)
+{
+	/*
+	 * IOSAPIC Version Register return 32 bit structure like:
+	 * {
+	 *	unsigned int version   : 8;
+	 *	unsigned int reserved1 : 8;
+	 *	unsigned int max_redir : 8;
+	 *	unsigned int reserved2 : 8;
+	 * }
+	 */
+	return iosapic_read(addr, IOSAPIC_VERSION);
+}
+
+/*
+ * if the given vector is already owned by other,
+ *  assign a new vector for the other and make the vector available
+ */
+static void __init
+iosapic_reassign_vector (int vector)
+{
+	int new_vector;
+
+	if (iosapic_intr_info[vector].rte_index >= 0 || iosapic_intr_info[vector].addr
+	    || iosapic_intr_info[vector].gsi_base || iosapic_intr_info[vector].dmode
+	    || iosapic_intr_info[vector].polarity || iosapic_intr_info[vector].trigger)
+	{
+		new_vector = assign_irq_vector(AUTO_ASSIGN);
+		printk(KERN_INFO "Reassigning vector %d to %d\n", vector, new_vector);
+		memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector],
+		       sizeof(struct iosapic_intr_info));
+		memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+		iosapic_intr_info[vector].rte_index = -1;
+	}
+}
+
+static void
+register_intr (unsigned int gsi, int vector, unsigned char delivery,
+	       unsigned long polarity, unsigned long trigger)
+{
+	irq_desc_t *idesc;
+	struct hw_interrupt_type *irq_type;
+	int rte_index;
+	int index;
+	unsigned long gsi_base;
+	void __iomem *iosapic_address;
+
+	index = find_iosapic(gsi);
+	if (index < 0) {
+		printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n", __FUNCTION__, gsi);
+		return;
+	}
+
+	iosapic_address = iosapic_lists[index].addr;
+	gsi_base = iosapic_lists[index].gsi_base;
+
+	rte_index = gsi - gsi_base;
+	iosapic_intr_info[vector].rte_index = rte_index;
+	iosapic_intr_info[vector].polarity = polarity;
+	iosapic_intr_info[vector].dmode    = delivery;
+	iosapic_intr_info[vector].addr     = iosapic_address;
+	iosapic_intr_info[vector].gsi_base = gsi_base;
+	iosapic_intr_info[vector].trigger  = trigger;
+	iosapic_intr_info[vector].refcnt++;
+
+	if (trigger == IOSAPIC_EDGE)
+		irq_type = &irq_type_iosapic_edge;
+	else
+		irq_type = &irq_type_iosapic_level;
+
+	idesc = irq_descp(vector);
+	if (idesc->handler != irq_type) {
+		if (idesc->handler != &no_irq_type)
+			printk(KERN_WARNING "%s: changing vector %d from %s to %s\n",
+			       __FUNCTION__, vector, idesc->handler->typename, irq_type->typename);
+		idesc->handler = irq_type;
+	}
+}
+
+static unsigned int
+get_target_cpu (unsigned int gsi, int vector)
+{
+#ifdef CONFIG_SMP
+	static int cpu = -1;
+
+	/*
+	 * If the platform supports redirection via XTP, let it
+	 * distribute interrupts.
+	 */
+	if (smp_int_redirect & SMP_IRQ_REDIRECTION)
+		return cpu_physical_id(smp_processor_id());
+
+	/*
+	 * Some interrupts (ACPI SCI, for instance) are registered
+	 * before the BSP is marked as online.
+	 */
+	if (!cpu_online(smp_processor_id()))
+		return cpu_physical_id(smp_processor_id());
+
+#ifdef CONFIG_NUMA
+	{
+		int num_cpus, cpu_index, iosapic_index, numa_cpu, i = 0;
+		cpumask_t cpu_mask;
+
+		iosapic_index = find_iosapic(gsi);
+		if (iosapic_index < 0 ||
+		    iosapic_lists[iosapic_index].node == MAX_NUMNODES)
+			goto skip_numa_setup;
+
+		cpu_mask = node_to_cpumask(iosapic_lists[iosapic_index].node);
+
+		for_each_cpu_mask(numa_cpu, cpu_mask) {
+			if (!cpu_online(numa_cpu))
+				cpu_clear(numa_cpu, cpu_mask);
+		}
+
+		num_cpus = cpus_weight(cpu_mask);
+
+		if (!num_cpus)
+			goto skip_numa_setup;
+
+		/* Use vector assigment to distribute across cpus in node */
+		cpu_index = vector % num_cpus;
+
+		for (numa_cpu = first_cpu(cpu_mask) ; i < cpu_index ; i++)
+			numa_cpu = next_cpu(numa_cpu, cpu_mask);
+
+		if (numa_cpu != NR_CPUS)
+			return cpu_physical_id(numa_cpu);
+	}
+skip_numa_setup:
+#endif
+	/*
+	 * Otherwise, round-robin interrupt vectors across all the
+	 * processors.  (It'd be nice if we could be smarter in the
+	 * case of NUMA.)
+	 */
+	do {
+		if (++cpu >= NR_CPUS)
+			cpu = 0;
+	} while (!cpu_online(cpu));
+
+	return cpu_physical_id(cpu);
+#else
+	return cpu_physical_id(smp_processor_id());
+#endif
+}
+
+/*
+ * ACPI can describe IOSAPIC interrupts via static tables and namespace
+ * methods.  This provides an interface to register those interrupts and
+ * program the IOSAPIC RTE.
+ */
+int
+iosapic_register_intr (unsigned int gsi,
+		       unsigned long polarity, unsigned long trigger)
+{
+	int vector;
+	unsigned int dest;
+	unsigned long flags;
+
+	/*
+	 * If this GSI has already been registered (i.e., it's a
+	 * shared interrupt, or we lost a race to register it),
+	 * don't touch the RTE.
+	 */
+	spin_lock_irqsave(&iosapic_lock, flags);
+	{
+		vector = gsi_to_vector(gsi);
+		if (vector > 0) {
+			iosapic_intr_info[vector].refcnt++;
+			spin_unlock_irqrestore(&iosapic_lock, flags);
+			return vector;
+		}
+
+		vector = assign_irq_vector(AUTO_ASSIGN);
+		dest = get_target_cpu(gsi, vector);
+		register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
+			polarity, trigger);
+
+		set_rte(vector, dest, 1);
+	}
+	spin_unlock_irqrestore(&iosapic_lock, flags);
+
+	printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
+	       gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
+	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
+	       cpu_logical_id(dest), dest, vector);
+
+	return vector;
+}
+
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+iosapic_unregister_intr (unsigned int gsi)
+{
+	unsigned long flags;
+	int irq, vector;
+	irq_desc_t *idesc;
+	int rte_index;
+	unsigned long trigger, polarity;
+
+	/*
+	 * If the irq associated with the gsi is not found,
+	 * iosapic_unregister_intr() is unbalanced. We need to check
+	 * this again after getting locks.
+	 */
+	irq = gsi_to_irq(gsi);
+	if (irq < 0) {
+		printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+		WARN_ON(1);
+		return;
+	}
+	vector = irq_to_vector(irq);
+
+	idesc = irq_descp(irq);
+	spin_lock_irqsave(&idesc->lock, flags);
+	spin_lock(&iosapic_lock);
+	{
+		rte_index = iosapic_intr_info[vector].rte_index;
+		if (rte_index < 0) {
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+			WARN_ON(1);
+			return;
+		}
+
+		if (--iosapic_intr_info[vector].refcnt > 0) {
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			return;
+		}
+
+		/*
+		 * If interrupt handlers still exist on the irq
+		 * associated with the gsi, don't unregister the
+		 * interrupt.
+		 */
+		if (idesc->action) {
+			iosapic_intr_info[vector].refcnt++;
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			printk(KERN_WARNING "Cannot unregister GSI. IRQ %u is still in use.\n", irq);
+			return;
+		}
+
+		/* Clear the interrupt controller descriptor. */
+		idesc->handler = &no_irq_type;
+
+		trigger  = iosapic_intr_info[vector].trigger;
+		polarity = iosapic_intr_info[vector].polarity;
+
+		/* Clear the interrupt information. */
+		memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+		iosapic_intr_info[vector].rte_index = -1;	/* mark as unused */
+	}
+	spin_unlock(&iosapic_lock);
+	spin_unlock_irqrestore(&idesc->lock, flags);
+
+	/* Free the interrupt vector */
+	free_irq_vector(vector);
+
+	printk(KERN_INFO "GSI %u (%s, %s) -> vector %d unregisterd.\n",
+	       gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
+	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
+	       vector);
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
+/*
+ * ACPI calls this when it finds an entry for a platform interrupt.
+ * Note that the irq_base and IOSAPIC address must be set in iosapic_init().
+ */
+int __init
+iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
+				int iosapic_vector, u16 eid, u16 id,
+				unsigned long polarity, unsigned long trigger)
+{
+	static const char * const name[] = {"unknown", "PMI", "INIT", "CPEI"};
+	unsigned char delivery;
+	int vector, mask = 0;
+	unsigned int dest = ((id << 8) | eid) & 0xffff;
+
+	switch (int_type) {
+	      case ACPI_INTERRUPT_PMI:
+		vector = iosapic_vector;
+		/*
+		 * since PMI vector is alloc'd by FW(ACPI) not by kernel,
+		 * we need to make sure the vector is available
+		 */
+		iosapic_reassign_vector(vector);
+		delivery = IOSAPIC_PMI;
+		break;
+	      case ACPI_INTERRUPT_INIT:
+		vector = assign_irq_vector(AUTO_ASSIGN);
+		delivery = IOSAPIC_INIT;
+		break;
+	      case ACPI_INTERRUPT_CPEI:
+		vector = IA64_CPE_VECTOR;
+		delivery = IOSAPIC_LOWEST_PRIORITY;
+		mask = 1;
+		break;
+	      default:
+		printk(KERN_ERR "iosapic_register_platform_irq(): invalid int type 0x%x\n", int_type);
+		return -1;
+	}
+
+	register_intr(gsi, vector, delivery, polarity, trigger);
+
+	printk(KERN_INFO "PLATFORM int %s (0x%x): GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
+	       int_type < ARRAY_SIZE(name) ? name[int_type] : "unknown",
+	       int_type, gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
+	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
+	       cpu_logical_id(dest), dest, vector);
+
+	set_rte(vector, dest, mask);
+	return vector;
+}
+
+
+/*
+ * ACPI calls this when it finds an entry for a legacy ISA IRQ override.
+ * Note that the gsi_base and IOSAPIC address must be set in iosapic_init().
+ */
+void __init
+iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
+			  unsigned long polarity,
+			  unsigned long trigger)
+{
+	int vector;
+	unsigned int dest = cpu_physical_id(smp_processor_id());
+
+	vector = isa_irq_to_vector(isa_irq);
+
+	register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, polarity, trigger);
+
+	DBG("ISA: IRQ %u -> GSI %u (%s,%s) -> CPU %d (0x%04x) vector %d\n",
+	    isa_irq, gsi, trigger == IOSAPIC_EDGE ? "edge" : "level",
+	    polarity == IOSAPIC_POL_HIGH ? "high" : "low",
+	    cpu_logical_id(dest), dest, vector);
+
+	set_rte(vector, dest, 1);
+}
+
+void __init
+iosapic_system_init (int system_pcat_compat)
+{
+	int vector;
+
+	for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
+		iosapic_intr_info[vector].rte_index = -1;	/* mark as unused */
+
+	pcat_compat = system_pcat_compat;
+	if (pcat_compat) {
+		/*
+		 * Disable the compatibility mode interrupts (8259 style), needs IN/OUT support
+		 * enabled.
+		 */
+		printk(KERN_INFO "%s: Disabling PC-AT compatible 8259 interrupts\n", __FUNCTION__);
+		outb(0xff, 0xA1);
+		outb(0xff, 0x21);
+	}
+}
+
+void __init
+iosapic_init (unsigned long phys_addr, unsigned int gsi_base)
+{
+	int num_rte;
+	unsigned int isa_irq, ver;
+	char __iomem *addr;
+
+	addr = ioremap(phys_addr, 0);
+	ver = iosapic_version(addr);
+
+	/*
+	 * The MAX_REDIR register holds the highest input pin
+	 * number (starting from 0).
+	 * We add 1 so that we can use it for number of pins (= RTEs)
+	 */
+	num_rte = ((ver >> 16) & 0xff) + 1;
+
+	iosapic_lists[num_iosapic].addr = addr;
+	iosapic_lists[num_iosapic].gsi_base = gsi_base;
+	iosapic_lists[num_iosapic].num_rte = num_rte;
+#ifdef CONFIG_NUMA
+	iosapic_lists[num_iosapic].node = MAX_NUMNODES;
+#endif
+	num_iosapic++;
+
+	if ((gsi_base == 0) && pcat_compat) {
+		/*
+		 * Map the legacy ISA devices into the IOSAPIC data.  Some of these may
+		 * get reprogrammed later on with data from the ACPI Interrupt Source
+		 * Override table.
+		 */
+		for (isa_irq = 0; isa_irq < 16; ++isa_irq)
+			iosapic_override_isa_irq(isa_irq, isa_irq, IOSAPIC_POL_HIGH, IOSAPIC_EDGE);
+	}
+}
+
+#ifdef CONFIG_NUMA
+void __init
+map_iosapic_to_node(unsigned int gsi_base, int node)
+{
+	int index;
+
+	index = find_iosapic(gsi_base);
+	if (index < 0) {
+		printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n",
+		       __FUNCTION__, gsi_base);
+		return;
+	}
+	iosapic_lists[index].node = node;
+	return;
+}
+#endif