+#if defined(RTE_ARCH_X86)
+static bool
+pci_one_device_iommu_support_va(struct rte_pci_device *dev)
+{
+#define VTD_CAP_MGAW_SHIFT 16
+#define VTD_CAP_MGAW_MASK (0x3fULL << VTD_CAP_MGAW_SHIFT)
+#define X86_VA_WIDTH 47 /* From Documentation/x86/x86_64/mm.txt */
+ struct rte_pci_addr *addr = &dev->addr;
+ char filename[PATH_MAX];
+ FILE *fp;
+ uint64_t mgaw, vtd_cap_reg = 0;
+
+ snprintf(filename, sizeof(filename),
+ "%s/" PCI_PRI_FMT "/iommu/intel-iommu/cap",
+ rte_pci_get_sysfs_path(), addr->domain, addr->bus, addr->devid,
+ addr->function);
+ if (access(filename, F_OK) == -1) {
+ /* We don't have an Intel IOMMU, assume VA supported*/
+ return true;
+ }
+
+ /* We have an intel IOMMU */
+ fp = fopen(filename, "r");
+ if (fp == NULL) {
+ RTE_LOG(ERR, EAL, "%s(): can't open %s\n", __func__, filename);
+ return false;
+ }
+
+ if (fscanf(fp, "%" PRIx64, &vtd_cap_reg) != 1) {
+ RTE_LOG(ERR, EAL, "%s(): can't read %s\n", __func__, filename);
+ fclose(fp);
+ return false;
+ }
+
+ fclose(fp);
+
+ mgaw = ((vtd_cap_reg & VTD_CAP_MGAW_MASK) >> VTD_CAP_MGAW_SHIFT) + 1;
+
+ /*
+ * Assuming there is no limitation by now. We can not know at this point
+ * because the memory has not been initialized yet. Setting the dma mask
+ * will force a check once memory initialization is done. We can not do
+ * a fallback to IOVA PA now, but if the dma check fails, the error
+ * message should advice for using '--iova-mode pa' if IOVA VA is the
+ * current mode.
+ */
+ rte_mem_set_dma_mask(mgaw);
+ return true;
+}
+#elif defined(RTE_ARCH_PPC_64)
+static bool
+pci_one_device_iommu_support_va(__rte_unused struct rte_pci_device *dev)
+{
+ return false;
+}
+#else
+static bool
+pci_one_device_iommu_support_va(__rte_unused struct rte_pci_device *dev)
+{
+ return true;
+}
+#endif
+
+/*
+ * All devices IOMMUs support VA as IOVA
+ */
+static bool
+pci_devices_iommu_support_va(void)
+{
+ struct rte_pci_device *dev = NULL;
+ struct rte_pci_driver *drv = NULL;
+
+ FOREACH_DRIVER_ON_PCIBUS(drv) {
+ FOREACH_DEVICE_ON_PCIBUS(dev) {
+ if (!rte_pci_match(drv, dev))
+ continue;
+ /*
+ * just one PCI device needs to be checked out because
+ * the IOMMU hardware is the same for all of them.
+ */
+ return pci_one_device_iommu_support_va(dev);
+ }
+ }
+ return true;
+}
+