Merge tag 'iommu-fixes-v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - Three AMD IOMMU patches to fix a boot crash on AMD Stoney systems and
   every other AMD IOMMU system booted with 'amd_iommu=off'.

   This is a v5.11 regression.

 - A Fix for the Tegra IOMMU driver to make sure it detects all IOMMUs

* tag 'iommu-fixes-v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/tegra-smmu: Make tegra_smmu_probe_device() to handle all IOMMU phandles
  iommu/amd: Keep track of amd_iommu_irq_remap state
  iommu/amd: Don't call early_amd_iommu_init() when AMD IOMMU is disabled
  iommu/amd: Move Stoney Ridge check to detect_ivrs()

drivers/iommu/amd/init.c

@@ -2714,7 +2714,6 @@ static int __init early_amd_iommu_init(void)
 	struct acpi_table_header *ivrs_base;
 	int i, remap_cache_sz, ret;
 	acpi_status status;
-	u32 pci_id;
 
 	if (!amd_iommu_detected)
 		return -ENODEV;
@@ -2804,16 +2803,6 @@ static int __init early_amd_iommu_init(void)
 	if (ret)
 		goto out;
 
-	/* Disable IOMMU if there's Stoney Ridge graphics */
-	for (i = 0; i < 32; i++) {
-		pci_id = read_pci_config(0, i, 0, 0);
-		if ((pci_id & 0xffff) == 0x1002 && (pci_id >> 16) == 0x98e4) {
-			pr_info("Disable IOMMU on Stoney Ridge\n");
-			amd_iommu_disabled = true;
-			break;
-		}
-	}
-
 	/* Disable any previously enabled IOMMUs */
 	if (!is_kdump_kernel() || amd_iommu_disabled)
 		disable_iommus();
@@ -2880,6 +2869,7 @@ static bool detect_ivrs(void)
 {
 	struct acpi_table_header *ivrs_base;
 	acpi_status status;
+	int i;
 
 	status = acpi_get_table("IVRS", 0, &ivrs_base);
 	if (status == AE_NOT_FOUND)
@@ -2892,6 +2882,17 @@ static bool detect_ivrs(void)
 
 	acpi_put_table(ivrs_base);
 
+	/* Don't use IOMMU if there is Stoney Ridge graphics */
+	for (i = 0; i < 32; i++) {
+		u32 pci_id;
+
+		pci_id = read_pci_config(0, i, 0, 0);
+		if ((pci_id & 0xffff) == 0x1002 && (pci_id >> 16) == 0x98e4) {
+			pr_info("Disable IOMMU on Stoney Ridge\n");
+			return false;
+		}
+	}
+
 	/* Make sure ACS will be enabled during PCI probe */
 	pci_request_acs();
 
@@ -2918,12 +2919,12 @@ static int __init state_next(void)
 		}
 		break;
 	case IOMMU_IVRS_DETECTED:
-		ret = early_amd_iommu_init();
-		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
-		if (init_state == IOMMU_ACPI_FINISHED && amd_iommu_disabled) {
-			pr_info("AMD IOMMU disabled\n");
+		if (amd_iommu_disabled) {
 			init_state = IOMMU_CMDLINE_DISABLED;
 			ret = -EINVAL;
+		} else {
+			ret = early_amd_iommu_init();
+			init_state = ret ? IOMMU_INIT_ERROR : IOMMU_ACPI_FINISHED;
 		}
 		break;
 	case IOMMU_ACPI_FINISHED:
@@ -3001,8 +3002,11 @@ int __init amd_iommu_prepare(void)
 	amd_iommu_irq_remap = true;
 
 	ret = iommu_go_to_state(IOMMU_ACPI_FINISHED);
-	if (ret)
+	if (ret) {
+		amd_iommu_irq_remap = false;
 		return ret;
+	}
+
 	return amd_iommu_irq_remap ? 0 : -ENODEV;
 }
 

drivers/iommu/tegra-smmu.c

@@ -849,12 +849,11 @@ static struct iommu_device *tegra_smmu_probe_device(struct device *dev)
 		smmu = tegra_smmu_find(args.np);
 		if (smmu) {
 			err = tegra_smmu_configure(smmu, dev, &args);
-			of_node_put(args.np);
 
-			if (err < 0)
+			if (err < 0) {
+				of_node_put(args.np);
 				return ERR_PTR(err);
-
-			break;
+			}
 		}
 
 		of_node_put(args.np);