diff --git a/drivers/irqchip/irq-gic-v3-its-platform-msi.c b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
index e4ba9f4cbd1ab607ee53b1c96d69ff97b11155f0..9e9dda33eb17460bd661c2a992a06594752bffb5 100644
--- a/drivers/irqchip/irq-gic-v3-its-platform-msi.c
+++ b/drivers/irqchip/irq-gic-v3-its-platform-msi.c
@@ -48,6 +48,11 @@ static int of_pmsi_get_dev_id(struct irq_domain *domain, struct device *dev,
 	return ret;
 }
 
+int __weak iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
+{
+	return -1;
+}
+
 static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
 			    int nvec, msi_alloc_info_t *info)
 {
@@ -57,7 +62,10 @@ static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
 
 	msi_info = msi_get_domain_info(domain->parent);
 
-	ret = of_pmsi_get_dev_id(domain, dev, &dev_id);
+	if (dev->of_node)
+		ret = of_pmsi_get_dev_id(domain, dev, &dev_id);
+	else
+		ret = iort_pmsi_get_dev_id(dev, &dev_id);
 	if (ret)
 		return ret;