diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 94b68213c50d..30ea89945543 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -2686,6 +2686,8 @@ static int __init arm_smmu_init(void)
 	if (ret)
 		return ret;
 
+	pci_request_acs();
+
 	return bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
 }
 
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 9345a3fcb706..ab365ec6184d 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -2096,8 +2096,10 @@ static int __init arm_smmu_init(void)
 #endif
 
 #ifdef CONFIG_PCI
-	if (!iommu_present(&pci_bus_type))
+	if (!iommu_present(&pci_bus_type)) {
+		pci_request_acs();
 		bus_set_iommu(&pci_bus_type, &arm_smmu_ops);
+	}
 #endif
 
 	return 0;