1 files changed, 43 insertions, 0 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index f5f524f92aa3..0307c8c1758f 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3586,3 +3586,46 @@ void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum)
 	dev_data->errata |= (1 << erratum);
 }
 EXPORT_SYMBOL(amd_iommu_enable_device_erratum);
+
+int amd_iommu_device_info(struct pci_dev *pdev,
+                          struct amd_iommu_device_info *info)
+{
+	int max_pasids;
+	int pos;
+
+	if (pdev == NULL || info == NULL)
+		return -EINVAL;
+
+	if (!amd_iommu_v2_supported())
+		return -EINVAL;
+
+	memset(info, 0, sizeof(*info));
+
+	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ATS);
+	if (pos)
+		info->flags |= AMD_IOMMU_DEVICE_FLAG_ATS_SUP;
+
+	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
+	if (pos)
+		info->flags |= AMD_IOMMU_DEVICE_FLAG_PRI_SUP;
+
+	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
+	if (pos) {
+		int features;
+
+		max_pasids = 1 << (9 * (amd_iommu_max_glx_val + 1));
+		max_pasids = min(max_pasids, (1 << 20));
+
+		info->flags |= AMD_IOMMU_DEVICE_FLAG_PASID_SUP;
+		info->max_pasids = min(pci_max_pasids(pdev), max_pasids);
+
+		features = pci_pasid_features(pdev);
+		if (features & PCI_PASID_CAP_EXEC)
+			info->flags |= AMD_IOMMU_DEVICE_FLAG_EXEC_SUP;
+		if (features & PCI_PASID_CAP_PRIV)
+			info->flags |= AMD_IOMMU_DEVICE_FLAG_PRIV_SUP;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(amd_iommu_device_info);