1 files changed, 29 insertions, 2 deletions

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 9c17dfa76703..2c181dfa23e0 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -168,6 +168,9 @@ static int amd_iommu_target_ivhd_type;
 u64 amd_iommu_efr;
 u64 amd_iommu_efr2;
 
+/* Host (v1) page table is not supported*/
+bool amd_iommu_hatdis;
+
 /* SNP is enabled on the system? */
 bool amd_iommu_snp_en;
 EXPORT_SYMBOL(amd_iommu_snp_en);
@@ -1792,6 +1795,11 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h,
 		if (h->efr_reg & BIT(IOMMU_EFR_XTSUP_SHIFT))
 			amd_iommu_xt_mode = IRQ_REMAP_X2APIC_MODE;
 
+		if (h->efr_attr & BIT(IOMMU_IVHD_ATTR_HATDIS_SHIFT)) {
+			pr_warn_once("Host Address Translation is not supported.\n");
+			amd_iommu_hatdis = true;
+		}
+
 		early_iommu_features_init(iommu, h);
 
 		break;
@@ -2112,7 +2120,15 @@ static int __init iommu_init_pci(struct amd_iommu *iommu)
 			return ret;
 	}
 
-	iommu_device_register(&iommu->iommu, &amd_iommu_ops, NULL);
+	ret = iommu_device_register(&iommu->iommu, &amd_iommu_ops, NULL);
+	if (ret || amd_iommu_pgtable == PD_MODE_NONE) {
+		/*
+		 * Remove sysfs if DMA translation is not supported by the
+		 * IOMMU. Do not return an error to enable IRQ remapping
+		 * in state_next(), DTE[V, TV] must eventually be set to 0.
+		 */
+		iommu_device_sysfs_remove(&iommu->iommu);
+	}
 
 	return pci_enable_device(iommu->dev);
 }
@@ -2573,7 +2589,7 @@ static void init_device_table_dma(struct amd_iommu_pci_seg *pci_seg)
 	u32 devid;
 	struct dev_table_entry *dev_table = pci_seg->dev_table;
 
-	if (dev_table == NULL)
+	if (!dev_table || amd_iommu_pgtable == PD_MODE_NONE)
 		return;
 
 	for (devid = 0; devid <= pci_seg->last_bdf; ++devid) {
@@ -3084,6 +3100,17 @@ static int __init early_amd_iommu_init(void)
 		}
 	}
 
+	if (amd_iommu_hatdis) {
+		/*
+		 * Host (v1) page table is not available. Attempt to use
+		 * Guest (v2) page table.
+		 */
+		if (amd_iommu_v2_pgtbl_supported())
+			amd_iommu_pgtable = PD_MODE_V2;
+		else
+			amd_iommu_pgtable = PD_MODE_NONE;
+	}
+
 	/* Disable any previously enabled IOMMUs */
 	if (!is_kdump_kernel() || amd_iommu_disabled)
 		disable_iommus();