diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index fba4f68..270ed22 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -1316,3 +1316,13 @@
 
 	return 0;
 }
+
+/*
+ * Check interrupt remapping support in DMAR table description.
+ */
+int dmar_ir_support(void)
+{
+	struct acpi_table_dmar *dmar;
+	dmar = (struct acpi_table_dmar *)dmar_tbl;
+	return dmar->flags & 0x1;
+}