[POWERPC] Use pseries_setup_i8259_cascade() in pseries_mpic_init_IRQ()

pseries_mpic_init_IRQ() implements the same logic as the xics code did to
find the i8259 cascade irq.  Now that we've pulled that logic out into
pseries_setup_i8259_cascade() we can use it in the mpic code.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 2 insertions, 41 deletions

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index eb079521fbf1..f66aa9c3b135 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -175,12 +175,9 @@ static void __init pseries_setup_i8259_cascade(void)
 
 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;
 
@@ -213,43 +210,7 @@ static void __init pseries_mpic_init_IRQ(void)
         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)