diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index c6740d7..2981ebf 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -22,7 +22,6 @@
 static LIST_HEAD(irq_domain_list);
 static DEFINE_MUTEX(irq_domain_mutex);
 
-#ifdef CONFIG_PPC
 static DEFINE_MUTEX(revmap_trees_mutex);
 static unsigned int irq_virq_count = NR_IRQS;
 static struct irq_domain *irq_default_domain;
@@ -694,125 +693,12 @@
 __initcall(irq_debugfs_init);
 #endif /* CONFIG_VIRQ_DEBUG */
 
-#else /* CONFIG_PPC */
-
-/**
- * irq_domain_add() - Register an irq_domain
- * @domain: ptr to initialized irq_domain structure
- *
- * Registers an irq_domain structure.  The irq_domain must at a minimum be
- * initialized with an ops structure pointer, and either a ->to_irq hook or
- * a valid irq_base value.  Everything else is optional.
- */
-void irq_domain_add(struct irq_domain *domain)
+int irq_domain_simple_map(struct irq_domain *d, unsigned int irq,
+			  irq_hw_number_t hwirq)
 {
-	struct irq_data *d;
-	int hwirq, irq;
-
-	/*
-	 * This assumes that the irq_domain owner has already allocated
-	 * the irq_descs.  This block will be removed when support for dynamic
-	 * allocation of irq_descs is added to irq_domain.
-	 */
-	irq_domain_for_each_irq(domain, hwirq, irq) {
-		d = irq_get_irq_data(irq);
-		if (!d) {
-			WARN(1, "error: assigning domain to non existant irq_desc");
-			return;
-		}
-		if (d->domain) {
-			/* things are broken; just report, don't clean up */
-			WARN(1, "error: irq_desc already assigned to a domain");
-			return;
-		}
-		d->domain = domain;
-		d->hwirq = hwirq;
-	}
-
-	mutex_lock(&irq_domain_mutex);
-	list_add(&domain->link, &irq_domain_list);
-	mutex_unlock(&irq_domain_mutex);
+	return 0;
 }
 
-/**
- * irq_domain_del() - Unregister an irq_domain
- * @domain: ptr to registered irq_domain.
- */
-void irq_domain_del(struct irq_domain *domain)
-{
-	struct irq_data *d;
-	int hwirq, irq;
-
-	mutex_lock(&irq_domain_mutex);
-	list_del(&domain->link);
-	mutex_unlock(&irq_domain_mutex);
-
-	/* Clear the irq_domain assignments */
-	irq_domain_for_each_irq(domain, hwirq, irq) {
-		d = irq_get_irq_data(irq);
-		d->domain = NULL;
-	}
-}
-
-#if defined(CONFIG_OF_IRQ)
-/**
- * irq_create_of_mapping() - Map a linux irq number from a DT interrupt spec
- *
- * Used by the device tree interrupt mapping code to translate a device tree
- * interrupt specifier to a valid linux irq number.  Returns either a valid
- * linux IRQ number or 0.
- *
- * When the caller no longer need the irq number returned by this function it
- * should arrange to call irq_dispose_mapping().
- */
-unsigned int irq_create_of_mapping(struct device_node *controller,
-				   const u32 *intspec, unsigned int intsize)
-{
-	struct irq_domain *domain;
-	unsigned long hwirq;
-	unsigned int irq, type;
-	int rc = -EINVAL;
-
-	/* Find a domain which can translate the irq spec */
-	mutex_lock(&irq_domain_mutex);
-	list_for_each_entry(domain, &irq_domain_list, link) {
-		if (!domain->ops->xlate)
-			continue;
-		rc = domain->ops->xlate(domain, controller,
-					intspec, intsize, &hwirq, &type);
-		if (rc == 0)
-			break;
-	}
-	mutex_unlock(&irq_domain_mutex);
-
-	if (rc != 0)
-		return 0;
-
-	irq = irq_domain_to_irq(domain, hwirq);
-	if (type != IRQ_TYPE_NONE)
-		irq_set_irq_type(irq, type);
-	pr_debug("%s: mapped hwirq=%i to irq=%i, flags=%x\n",
-		 controller->full_name, (int)hwirq, irq, type);
-	return irq;
-}
-EXPORT_SYMBOL_GPL(irq_create_of_mapping);
-
-/**
- * irq_dispose_mapping() - Discard a mapping created by irq_create_of_mapping()
- * @irq: linux irq number to be discarded
- *
- * Calling this function indicates the caller no longer needs a reference to
- * the linux irq number returned by a prior call to irq_create_of_mapping().
- */
-void irq_dispose_mapping(unsigned int irq)
-{
-	/*
-	 * nothing yet; will be filled when support for dynamic allocation of
-	 * irq_descs is added to irq_domain
-	 */
-}
-EXPORT_SYMBOL_GPL(irq_dispose_mapping);
-
 int irq_domain_simple_xlate(struct irq_domain *d,
 			    struct device_node *controller,
 			    const u32 *intspec, unsigned int intsize,
@@ -822,10 +708,6 @@
 		return -EINVAL;
 	if (intsize < 1)
 		return -EINVAL;
-	if (d->nr_irq && ((intspec[0] < d->hwirq_base) ||
-	    (intspec[0] >= d->hwirq_base + d->nr_irq)))
-		return -EINVAL;
-
 	*out_hwirq = intspec[0];
 	*out_type = IRQ_TYPE_NONE;
 	if (intsize > 1)
@@ -833,23 +715,17 @@
 	return 0;
 }
 
-/**
- * irq_domain_create_simple() - Set up a 'simple' translation range
- */
+struct irq_domain_ops irq_domain_simple_ops = {
+	.map = irq_domain_simple_map,
+	.xlate = irq_domain_simple_xlate,
+};
+EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
+
+#ifdef CONFIG_OF_IRQ
 void irq_domain_add_simple(struct device_node *controller, int irq_base)
 {
-	struct irq_domain *domain;
-
-	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
-	if (!domain) {
-		WARN_ON(1);
-		return;
-	}
-
-	domain->irq_base = irq_base;
-	domain->of_node = of_node_get(controller);
-	domain->ops = &irq_domain_simple_ops;
-	irq_domain_add(domain);
+	irq_domain_add_legacy(controller, 32, irq_base, 0,
+			      &irq_domain_simple_ops, NULL);
 }
 EXPORT_SYMBOL_GPL(irq_domain_add_simple);
 
@@ -864,13 +740,4 @@
 		irq_domain_add_simple(node, irq_start);
 }
 EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
-#endif /* CONFIG_OF_IRQ */
-
-struct irq_domain_ops irq_domain_simple_ops = {
-#ifdef CONFIG_OF_IRQ
-	.xlate = irq_domain_simple_xlate,
-#endif /* CONFIG_OF_IRQ */
-};
-EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
-
-#endif /* !CONFIG_PPC */
+#endif