static void __init pseries_mpic_init_IRQ(void)
 {
-       struct device_node *np, *old, *cascade = NULL;
-        const unsigned int *addrp;
-       unsigned long intack = 0;
+       struct device_node *np;
        const unsigned int *opprop;
        unsigned long openpic_addr = 0;
-       unsigned int cascade_irq;
        int naddr, n, i, opplen;
        struct mpic *mpic;
 
        mpic_init(mpic);
 
        /* Look for cascade */
-       for_each_node_by_type(np, "interrupt-controller")
-               if (of_device_is_compatible(np, "chrp,iic")) {
-                       cascade = np;
-                       break;
-               }
-       if (cascade == NULL)
-               return;
-
-       cascade_irq = irq_of_parse_and_map(cascade, 0);
-       if (cascade_irq == NO_IRQ) {
-               printk(KERN_ERR "mpic: failed to map cascade interrupt");
-               return;
-       }
-
-       /* Check ACK type */
-       for (old = of_node_get(cascade); old != NULL ; old = np) {
-               np = of_get_parent(old);
-               of_node_put(old);
-               if (np == NULL)
-                       break;
-               if (strcmp(np->name, "pci") != 0)
-                       continue;
-               addrp = of_get_property(np, "8259-interrupt-acknowledge",
-                                           NULL);
-               if (addrp == NULL)
-                       continue;
-               naddr = of_n_addr_cells(np);
-               intack = addrp[naddr-1];
-               if (naddr > 1)
-                       intack |= ((unsigned long)addrp[naddr-2]) << 32;
-       }
-       if (intack)
-               printk(KERN_DEBUG "mpic: PCI 8259 intack at 0x%016lx\n",
-                      intack);
-       i8259_init(cascade, intack);
-       of_node_put(cascade);
-       set_irq_chained_handler(cascade_irq, pseries_8259_cascade);
+       pseries_setup_i8259_cascade();
 }
 
 static void __init pseries_xics_init_IRQ(void)