irqdomain: Do irq_find_mapping and set_type for hierarchy irqdomain in case OF

It is possible to call irq_create_of_mapping to create/translate the
same IRQ from DT for multiple times. Perform irq_find_mapping check
and set_type for hierarchy irqdomain in irq_create_of_mapping() to
avoid duplicate these functionality in all outer most irqdomain.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

kernel/irq/irqdomain.c

@@ -478,11 +478,6 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
 		return 0;
 	}
 
-	if (irq_domain_is_hierarchy(domain)) {
-		virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data);
-		return virq <= 0 ? 0 : virq;
-	}
-
 	/* If domain has no translation, then we assume interrupt line */
 	if (domain->ops->xlate == NULL)
 		hwirq = irq_data->args[0];
@@ -492,10 +487,24 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
 			return 0;
 	}
 
-	/* Create mapping */
-	virq = irq_create_mapping(domain, hwirq);
-	if (!virq)
-		return virq;
+	if (irq_domain_is_hierarchy(domain)) {
+		/*
+		 * If we've already configured this interrupt,
+		 * don't do it again, or hell will break loose.
+		 */
+		virq = irq_find_mapping(domain, hwirq);
+		if (virq)
+			return virq;
+
+		virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data);
+		if (virq <= 0)
+			return 0;
+	} else {
+		/* Create mapping */
+		virq = irq_create_mapping(domain, hwirq);
+		if (!virq)
+			return virq;
+	}
 
 	/* Set type if specified and different than the current one */
 	if (type != IRQ_TYPE_NONE &&