diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 4a9feff340da..15e25f712f39 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1745,6 +1745,9 @@ static int __init iommu_init_pci(struct amd_iommu *iommu)
 	/* Prevent binding other PCI device drivers to IOMMU devices */
 	iommu->dev->match_driver = false;
 
+	/* ACPI _PRT won't have an IRQ for IOMMU */
+	iommu->dev->irq_managed = 1;
+
 	pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET,
 			      &iommu->cap);
 	pci_read_config_dword(iommu->dev, cap_ptr + MMIO_RANGE_OFFSET,