Pull sgi into release branch
diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 73ef4a85..ef2fe47 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -590,6 +590,9 @@
  */
 int acpi_register_gsi(u32 gsi, int triggering, int polarity)
 {
+	if (acpi_irq_model == ACPI_IRQ_MODEL_PLATFORM)
+		return gsi;
+
 	if (has_8259 && gsi < 16)
 		return isa_irq_to_vector(gsi);
 
diff --git a/arch/ia64/sn/kernel/io_acpi_init.c b/arch/ia64/sn/kernel/io_acpi_init.c
index 99d7f27..cb96b4e 100644
--- a/arch/ia64/sn/kernel/io_acpi_init.c
+++ b/arch/ia64/sn/kernel/io_acpi_init.c
@@ -223,6 +223,9 @@
 	u64 result;
 	s64 status;
 
+	/* SN Altix does not follow the IOSAPIC IRQ routing model */
+	acpi_irq_model = ACPI_IRQ_MODEL_PLATFORM;
+
 	acpi_bus_register_driver(&acpi_sn_hubdev_driver);
 	status = sal_ioif_init(&result);
 	if (status || result)
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 279c4ba..766332e 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -561,6 +561,9 @@
 	case ACPI_IRQ_MODEL_IOSAPIC:
 		message = "IOSAPIC";
 		break;
+	case ACPI_IRQ_MODEL_PLATFORM:
+		message = "platform specific model";
+		break;
 	default:
 		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
 		return -ENODEV;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 2b0c955..91f1f23 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -47,6 +47,7 @@
 	ACPI_IRQ_MODEL_PIC = 0,
 	ACPI_IRQ_MODEL_IOAPIC,
 	ACPI_IRQ_MODEL_IOSAPIC,
+	ACPI_IRQ_MODEL_PLATFORM,
 	ACPI_IRQ_MODEL_COUNT
 };