diff --git a/arch/openrisc/kernel/irq.c b/arch/openrisc/kernel/irq.c
index 61327985f967b8684fcc2f8132c761fd61dc0eec..8ec77bc9f1e7d7b62694d1105ef5581374d0ebf6 100644
--- a/arch/openrisc/kernel/irq.c
+++ b/arch/openrisc/kernel/irq.c
@@ -87,9 +87,11 @@ static void or1k_pic_mask_ack(struct irq_data *data)
 	/* Comments for pic_ack apply here, too */
 
 #ifdef CONFIG_OR1K_1200
+	mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
 	mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
 #else
 	WARN(1, "Interrupt handling possibly broken\n");
+	mtspr(SPR_PICMR, (1UL << data->hwirq));
 	mtspr(SPR_PICSR, (1UL << data->hwirq));
 #endif
 }