diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index ddd59fe786f8ad9088b4a01724afb9578eac2e4a..5ab5c4f8dcb013f2e94927c5d41084f3308818d8 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -20,6 +20,7 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/irqdomain.h>
+#include <linux/of_irq.h>
 
 #include "pci.h"
 
@@ -1327,4 +1328,35 @@ struct irq_domain *pci_msi_create_default_irq_domain(struct fwnode_handle *fwnod
 
 	return domain;
 }
+
+static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data)
+{
+	u32 *pa = data;
+
+	*pa = alias;
+	return 0;
+}
+/**
+ * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
+ * @domain:	The interrupt domain
+ * @pdev:	The PCI device.
+ *
+ * The RID for a device is formed from the alias, with a firmware
+ * supplied mapping applied
+ *
+ * Returns: The RID.
+ */
+u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev)
+{
+	struct device_node *of_node;
+	u32 rid = 0;
+
+	pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);
+
+	of_node = irq_domain_get_of_node(domain);
+	if (of_node)
+		rid = of_msi_map_rid(&pdev->dev, of_node, rid);
+
+	return rid;
+}
 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
diff --git a/include/linux/msi.h b/include/linux/msi.h
index 32a24b9a9556791385f09b63ff9d802d31a3fbb8..87723751054dd8ea4e60e4cba1a403ccc7590d04 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -294,6 +294,7 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev,
 					  struct msi_desc *desc);
 int pci_msi_domain_check_cap(struct irq_domain *domain,
 			     struct msi_domain_info *info, struct device *dev);
+u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev);
 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
 
 #endif /* LINUX_MSI_H */