diff --git a/sys/powerpc/include/intr.h b/sys/powerpc/include/intr.h
--- a/sys/powerpc/include/intr.h
+++ b/sys/powerpc/include/intr.h
@@ -38,6 +38,11 @@
 
 extern struct intr_event *intr2event(interrupt_t *intr);
 
+#define INTR_FOREACH(i)							\
+	for (u_int INTR_FOREACH = 0;					\
+	    ((i) = powerpc_get_irqnum(INTR_FOREACH)) < ((u_int)-1);	\
+	    ++INTR_FOREACH)
+
 /* FreeBSD standard interrupt controller interface */
 
 #define	INTR_VECTORS	256
@@ -73,4 +78,6 @@
 void	powerpc_intr_mask(u_int irq);
 void	powerpc_intr_unmask(u_int irq);
 
+u_int	powerpc_get_irqnum(u_int idx);
+
 #endif /* _MACHINE_INTR_MACHDEP_H_ */
diff --git a/sys/powerpc/powerpc/intr_machdep.c b/sys/powerpc/powerpc/intr_machdep.c
--- a/sys/powerpc/powerpc/intr_machdep.c
+++ b/sys/powerpc/powerpc/intr_machdep.c
@@ -307,6 +307,15 @@
 	return (NULL);
 }
 
+u_int
+powerpc_get_irqnum(u_int idx)
+{
+
+	if (idx >= num_io_irqs)
+		return (-1);
+	return (powerpc_intrs[idx].irq);
+}
+
 struct intr_event *
 intr2event(interrupt_t *intr)
 {
diff --git a/sys/sys/intr.h b/sys/sys/intr.h
--- a/sys/sys/intr.h
+++ b/sys/sys/intr.h
@@ -45,6 +45,14 @@
 
 #define	intr2event(intr)	((intr) == NULL ? NULL : (intr)->isrc_event)
 
+#define INTR_FOREACH(i)							\
+	for ((i) = 0; __extension__ ({					\
+		do {							\
+			++(i);						\
+		} while ((i) < intr_nirq && intr_lookup(i) == NULL);	\
+		(i) < intr_nirq;					\
+	}); )
+
 /* FreeBSD standard interrupt controller interface */
 
 #define	INTR_IRQ_INVALID	0xFFFFFFFF
diff --git a/sys/x86/include/intr.h b/sys/x86/include/intr.h
--- a/sys/x86/include/intr.h
+++ b/sys/x86/include/intr.h
@@ -40,6 +40,14 @@
 
 #define	intr2event(intr)	((intr) == NULL ? NULL : (intr)->is_event)
 
+#define INTR_FOREACH(i)							\
+	for ((i) = 0; __extension__ ({					\
+		do {							\
+			++(i);						\
+		} while ((i) < num_io_irqs && intr_lookup(i) == NULL);	\
+		(i) < num_io_irqs;					\
+	}); )
+
 /* FreeBSD standard interrupt controller interface */
 
 /*