diff --git a/arch/powerpc/sysdev/ipic.c b/arch/powerpc/sysdev/ipic.c
index f267ee0afc08..16f1edd78c40 100644
--- a/arch/powerpc/sysdev/ipic.c
+++ b/arch/powerpc/sysdev/ipic.c
@@ -315,6 +315,7 @@ static struct ipic_info ipic_info[] = {
 		.prio_mask = 7,
 	},
 	[48] = {
+		.ack	= IPIC_SEPNR,
 		.mask	= IPIC_SEMSR,
 		.prio	= IPIC_SMPRR_A,
 		.force	= IPIC_SEFCR,