// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2016, Semihalf * Author: Tomasz Nowicki * * This file implements early detection/parsing of I/O mapping * reported to OS through firmware via I/O Remapping Table (IORT) * IORT document number: ARM DEN 0049A */ #define pr_fmt(fmt) "ACPI: IORT: " fmt #include #include #include #include #include #include #include #include #include #define IORT_TYPE_MASK(type) (1 << (type)) #define IORT_MSI_TYPE (1 << ACPI_IORT_NODE_ITS_GROUP) #define IORT_IOMMU_TYPE ((1 << ACPI_IORT_NODE_SMMU) | \ (1 << ACPI_IORT_NODE_SMMU_V3)) struct iort_its_msi_chip { struct list_head list; struct fwnode_handle *fw_node; phys_addr_t base_addr; u32 translation_id; }; struct iort_fwnode { struct list_head list; struct acpi_iort_node *iort_node; struct fwnode_handle *fwnode; }; static LIST_HEAD(iort_fwnode_list); static DEFINE_SPINLOCK(iort_fwnode_lock); /** * iort_set_fwnode() - Create iort_fwnode and use it to register * iommu data in the iort_fwnode_list * * @iort_node: IORT table node associated with the IOMMU * @fwnode: fwnode associated with the IORT node * * Returns: 0 on success * <0 on failure */ static inline int iort_set_fwnode(struct acpi_iort_node *iort_node, struct fwnode_handle *fwnode) { struct iort_fwnode *np; np = kzalloc(sizeof(struct iort_fwnode), GFP_ATOMIC); if (WARN_ON(!np)) return -ENOMEM; INIT_LIST_HEAD(&np->list); np->iort_node = iort_node; np->fwnode = fwnode; spin_lock(&iort_fwnode_lock); list_add_tail(&np->list, &iort_fwnode_list); spin_unlock(&iort_fwnode_lock); return 0; } /** * iort_get_fwnode() - Retrieve fwnode associated with an IORT node * * @node: IORT table node to be looked-up * * Returns: fwnode_handle pointer on success, NULL on failure */ static inline struct fwnode_handle *iort_get_fwnode( struct acpi_iort_node *node) { struct iort_fwnode *curr; struct fwnode_handle *fwnode = NULL; spin_lock(&iort_fwnode_lock); list_for_each_entry(curr, &iort_fwnode_list, list) { if (curr->iort_node == node) { fwnode = curr->fwnode; break; } } spin_unlock(&iort_fwnode_lock); return fwnode; } /** * iort_delete_fwnode() - Delete fwnode associated with an IORT node * * @node: IORT table node associated with fwnode to delete */ static inline void iort_delete_fwnode(struct acpi_iort_node *node) { struct iort_fwnode *curr, *tmp; spin_lock(&iort_fwnode_lock); list_for_each_entry_safe(curr, tmp, &iort_fwnode_list, list) { if (curr->iort_node == node) { list_del(&curr->list); kfree(curr); break; } } spin_unlock(&iort_fwnode_lock); } /** * iort_get_iort_node() - Retrieve iort_node associated with an fwnode * * @fwnode: fwnode associated with device to be looked-up * * Returns: iort_node pointer on success, NULL on failure */ static inline struct acpi_iort_node *iort_get_iort_node( struct fwnode_handle *fwnode) { struct iort_fwnode *curr; struct acpi_iort_node *iort_node = NULL; spin_lock(&iort_fwnode_lock); list_for_each_entry(curr, &iort_fwnode_list, list) { if (curr->fwnode == fwnode) { iort_node = curr->iort_node; break; } } spin_unlock(&iort_fwnode_lock); return iort_node; } typedef acpi_status (*iort_find_node_callback) (struct acpi_iort_node *node, void *context); /* Root pointer to the mapped IORT table */ static struct acpi_table_header *iort_table; static LIST_HEAD(iort_msi_chip_list); static DEFINE_SPINLOCK(iort_msi_chip_lock); /** * iort_register_domain_token() - register domain token along with related * ITS ID and base address to the list from where we can get it back later on. * @trans_id: ITS ID. * @base: ITS base address. * @fw_node: Domain token. * * Returns: 0 on success, -ENOMEM if no memory when allocating list element */ int iort_register_domain_token(int trans_id, phys_addr_t base, struct fwnode_handle *fw_node) { struct iort_its_msi_chip *its_msi_chip; its_msi_chip = kzalloc(sizeof(*its_msi_chip), GFP_KERNEL); if (!its_msi_chip) return -ENOMEM; its_msi_chip->fw_node = fw_node; its_msi_chip->translation_id = trans_id; its_msi_chip->base_addr = base; spin_lock(&iort_msi_chip_lock); list_add(&its_msi_chip->list, &iort_msi_chip_list); spin_unlock(&iort_msi_chip_lock); return 0; } /** * iort_deregister_domain_token() - Deregister domain token based on ITS ID * @trans_id: ITS ID. * * Returns: none. */ void iort_deregister_domain_token(int trans_id) { struct iort_its_msi_chip *its_msi_chip, *t; spin_lock(&iort_msi_chip_lock); list_for_each_entry_safe(its_msi_chip, t, &iort_msi_chip_list, list) { if (its_msi_chip->translation_id == trans_id) { list_del(&its_msi_chip->list); kfree(its_msi_chip); break; } } spin_unlock(&iort_msi_chip_lock); } /** * iort_find_domain_token() - Find domain token based on given ITS ID * @trans_id: ITS ID. * * Returns: domain token when find on the list, NULL otherwise */ struct fwnode_handle *iort_find_domain_token(int trans_id) { struct fwnode_handle *fw_node = NULL; struct iort_its_msi_chip *its_msi_chip; spin_lock(&iort_msi_chip_lock); list_for_each_entry(its_msi_chip, &iort_msi_chip_list, list) { if (its_msi_chip->translation_id == trans_id) { fw_node = its_msi_chip->fw_node; break; } } spin_unlock(&iort_msi_chip_lock); return fw_node; } static struct acpi_iort_node *iort_scan_node(enum acpi_iort_node_type type, iort_find_node_callback callback, void *context) { struct acpi_iort_node *iort_node, *iort_end; struct acpi_table_iort *iort; int i; if (!iort_table) return NULL; /* Get the first IORT node */ iort = (struct acpi_table_iort *)iort_table; iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort, iort->node_offset); iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, iort_table->length); for (i = 0; i < iort->node_count; i++) { if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND, "IORT node pointer overflows, bad table!\n")) return NULL; if (iort_node->type == type && ACPI_SUCCESS(callback(iort_node, context))) return iort_node; iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node, iort_node->length); } return NULL; } static acpi_status iort_match_node_callback(struct acpi_iort_node *node, void *context) { struct device *dev = context; acpi_status status = AE_NOT_FOUND; if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT) { struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_device *adev; struct acpi_iort_named_component *ncomp; struct device *nc_dev = dev; /* * Walk the device tree to find a device with an * ACPI companion; there is no point in scanning * IORT for a device matching a named component if * the device does not have an ACPI companion to * start with. */ do { adev = ACPI_COMPANION(nc_dev); if (adev) break; nc_dev = nc_dev->parent; } while (nc_dev); if (!adev) goto out; status = acpi_get_name(adev->handle, ACPI_FULL_PATHNAME, &buf); if (ACPI_FAILURE(status)) { dev_warn(nc_dev, "Can't get device full path name\n"); goto out; } ncomp = (struct acpi_iort_named_component *)node->node_data; status = !strcmp(ncomp->device_name, buf.pointer) ? AE_OK : AE_NOT_FOUND; acpi_os_free(buf.pointer); } else if (node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) { struct acpi_iort_root_complex *pci_rc; struct pci_bus *bus; bus = to_pci_bus(dev); pci_rc = (struct acpi_iort_root_complex *)node->node_data; /* * It is assumed that PCI segment numbers maps one-to-one * with root complexes. Each segment number can represent only * one root complex. */ status = pci_rc->pci_segment_number == pci_domain_nr(bus) ? AE_OK : AE_NOT_FOUND; } out: return status; } static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in, u32 *rid_out, bool check_overlap) { /* Single mapping does not care for input id */ if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) { if (type == ACPI_IORT_NODE_NAMED_COMPONENT || type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) { *rid_out = map->output_base; return 0; } pr_warn(FW_BUG "[map %p] SINGLE MAPPING flag not allowed for node type %d, skipping ID map\n", map, type); return -ENXIO; } if (rid_in < map->input_base || (rid_in > map->input_base + map->id_count)) return -ENXIO; if (check_overlap) { /* * We already found a mapping for this input ID at the end of * another region. If it coincides with the start of this * region, we assume the prior match was due to the off-by-1 * issue mentioned below, and allow it to be superseded. * Otherwise, things are *really* broken, and we just disregard * duplicate matches entirely to retain compatibility. */ pr_err(FW_BUG "[map %p] conflicting mapping for input ID 0x%x\n", map, rid_in); if (rid_in != map->input_base) return -ENXIO; pr_err(FW_BUG "applying workaround.\n"); } *rid_out = map->output_base + (rid_in - map->input_base); /* * Due to confusion regarding the meaning of the id_count field (which * carries the number of IDs *minus 1*), we may have to disregard this * match if it is at the end of the range, and overlaps with the start * of another one. */ if (map->id_count > 0 && rid_in == map->input_base + map->id_count) return -EAGAIN; return 0; } static struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node, u32 *id_out, int index) { struct acpi_iort_node *parent; struct acpi_iort_id_mapping *map; if (!node->mapping_offset || !node->mapping_count || index >= node->mapping_count) return NULL; map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, node->mapping_offset + index * sizeof(*map)); /* Firmware bug! */ if (!map->output_reference) { pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n", node, node->type); return NULL; } parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, map->output_reference); if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) { if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT || node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX || node->type == ACPI_IORT_NODE_SMMU_V3 || node->type == ACPI_IORT_NODE_PMCG) { *id_out = map->output_base; return parent; } } return NULL; } static int iort_get_id_mapping_index(struct acpi_iort_node *node) { struct acpi_iort_smmu_v3 *smmu; struct acpi_iort_pmcg *pmcg; switch (node->type) { case ACPI_IORT_NODE_SMMU_V3: /* * SMMUv3 dev ID mapping index was introduced in revision 1 * table, not available in revision 0 */ if (node->revision < 1) return -EINVAL; smmu = (struct acpi_iort_smmu_v3 *)node->node_data; /* * ID mapping index is only ignored if all interrupts are * GSIV based */ if (smmu->event_gsiv && smmu->pri_gsiv && smmu->gerr_gsiv && smmu->sync_gsiv) return -EINVAL; if (smmu->id_mapping_index >= node->mapping_count) { pr_err(FW_BUG "[node %p type %d] ID mapping index overflows valid mappings\n", node, node->type); return -EINVAL; } return smmu->id_mapping_index; case ACPI_IORT_NODE_PMCG: pmcg = (struct acpi_iort_pmcg *)node->node_data; if (pmcg->overflow_gsiv || node->mapping_count == 0) return -EINVAL; return 0; default: return -EINVAL; } } static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node, u32 id_in, u32 *id_out, u8 type_mask) { u32 id = id_in; /* Parse the ID mapping tree to find specified node type */ while (node) { struct acpi_iort_id_mapping *map; int i, index, rc = 0; u32 out_ref = 0, map_id = id; if (IORT_TYPE_MASK(node->type) & type_mask) { if (id_out) *id_out = id; return node; } if (!node->mapping_offset || !node->mapping_count) goto fail_map; map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, node->mapping_offset); /* Firmware bug! */ if (!map->output_reference) { pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n", node, node->type); goto fail_map; } /* * Get the special ID mapping index (if any) and skip its * associated ID map to prevent erroneous multi-stage * IORT ID translations. */ index = iort_get_id_mapping_index(node); /* Do the ID translation */ for (i = 0; i < node->mapping_count; i++, map++) { /* if it is special mapping index, skip it */ if (i == index) continue; rc = iort_id_map(map, node->type, map_id, &id, out_ref); if (!rc) break; if (rc == -EAGAIN) out_ref = map->output_reference; } if (i == node->mapping_count && !out_ref) goto fail_map; node = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, rc ? out_ref : map->output_reference); } fail_map: /* Map input ID to output ID unchanged on mapping failure */ if (id_out) *id_out = id_in; return NULL; } static struct acpi_iort_node *iort_node_map_platform_id( struct acpi_iort_node *node, u32 *id_out, u8 type_mask, int index) { struct acpi_iort_node *parent; u32 id; /* step 1: retrieve the initial dev id */ parent = iort_node_get_id(node, &id, index); if (!parent) return NULL; /* * optional step 2: map the initial dev id if its parent is not * the target type we want, map it again for the use cases such * as NC (named component) -> SMMU -> ITS. If the type is matched, * return the initial dev id and its parent pointer directly. */ if (!(IORT_TYPE_MASK(parent->type) & type_mask)) parent = iort_node_map_id(parent, id, id_out, type_mask); else if (id_out) *id_out = id; return parent; } static struct acpi_iort_node *iort_find_dev_node(struct device *dev) { struct pci_bus *pbus; if (!dev_is_pci(dev)) { struct acpi_iort_node *node; /* * scan iort_fwnode_list to see if it's an iort platform * device (such as SMMU, PMCG),its iort node already cached * and associated with fwnode when iort platform devices * were initialized. */ node = iort_get_iort_node(dev->fwnode); if (node) return node; /* * if not, then it should be a platform device defined in * DSDT/SSDT (with Named Component node in IORT) */ return iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT, iort_match_node_callback, dev); } pbus = to_pci_dev(dev)->bus; return iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX, iort_match_node_callback, &pbus->dev); } /** * iort_msi_map_id() - Map a MSI input ID for a device * @dev: The device for which the mapping is to be done. * @input_id: The device input ID. * * Returns: mapped MSI ID on success, input ID otherwise */ u32 iort_msi_map_id(struct device *dev, u32 input_id) { struct acpi_iort_node *node; u32 dev_id; node = iort_find_dev_node(dev); if (!node) return input_id; iort_node_map_id(node, input_id, &dev_id, IORT_MSI_TYPE); return dev_id; } /** * iort_pmsi_get_dev_id() - Get the device id for a device * @dev: The device for which the mapping is to be done. * @dev_id: The device ID found. * * Returns: 0 for successful find a dev id, -ENODEV on error */ int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id) { int i, index; struct acpi_iort_node *node; node = iort_find_dev_node(dev); if (!node) return -ENODEV; index = iort_get_id_mapping_index(node); /* if there is a valid index, go get the dev_id directly */ if (index >= 0) { if (iort_node_get_id(node, dev_id, index)) return 0; } else { for (i = 0; i < node->mapping_count; i++) { if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE, i)) return 0; } } return -ENODEV; } static int __maybe_unused iort_find_its_base(u32 its_id, phys_addr_t *base) { struct iort_its_msi_chip *its_msi_chip; int ret = -ENODEV; spin_lock(&iort_msi_chip_lock); list_for_each_entry(its_msi_chip, &iort_msi_chip_list, list) { if (its_msi_chip->translation_id == its_id) { *base = its_msi_chip->base_addr; ret = 0; break; } } spin_unlock(&iort_msi_chip_lock); return ret; } /** * iort_dev_find_its_id() - Find the ITS identifier for a device * @dev: The device. * @id: Device's ID * @idx: Index of the ITS identifier list. * @its_id: ITS identifier. * * Returns: 0 on success, appropriate error value otherwise */ static int iort_dev_find_its_id(struct device *dev, u32 id, unsigned int idx, int *its_id) { struct acpi_iort_its_group *its; struct acpi_iort_node *node; node = iort_find_dev_node(dev); if (!node) return -ENXIO; node = iort_node_map_id(node, id, NULL, IORT_MSI_TYPE); if (!node) return -ENXIO; /* Move to ITS specific data */ its = (struct acpi_iort_its_group *)node->node_data; if (idx >= its->its_count) { dev_err(dev, "requested ITS ID index [%d] overruns ITS entries [%d]\n", idx, its->its_count); return -ENXIO; } *its_id = its->identifiers[idx]; return 0; } /** * iort_get_device_domain() - Find MSI domain related to a device * @dev: The device. * @id: Requester ID for the device. * @bus_token: irq domain bus token. * * Returns: the MSI domain for this device, NULL otherwise */ struct irq_domain *iort_get_device_domain(struct device *dev, u32 id, enum irq_domain_bus_token bus_token) { struct fwnode_handle *handle; int its_id; if (iort_dev_find_its_id(dev, id, 0, &its_id)) return NULL; handle = iort_find_domain_token(its_id); if (!handle) return NULL; return irq_find_matching_fwnode(handle, bus_token); } static void iort_set_device_domain(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_its_group *its; struct acpi_iort_node *msi_parent; struct acpi_iort_id_mapping *map; struct fwnode_handle *iort_fwnode; struct irq_domain *domain; int index; index = iort_get_id_mapping_index(node); if (index < 0) return; map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, node->mapping_offset + index * sizeof(*map)); /* Firmware bug! */ if (!map->output_reference || !(map->flags & ACPI_IORT_ID_SINGLE_MAPPING)) { pr_err(FW_BUG "[node %p type %d] Invalid MSI mapping\n", node, node->type); return; } msi_parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, map->output_reference); if (!msi_parent || msi_parent->type != ACPI_IORT_NODE_ITS_GROUP) return; /* Move to ITS specific data */ its = (struct acpi_iort_its_group *)msi_parent->node_data; iort_fwnode = iort_find_domain_token(its->identifiers[0]); if (!iort_fwnode) return; domain = irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI); if (domain) dev_set_msi_domain(dev, domain); } /** * iort_get_platform_device_domain() - Find MSI domain related to a * platform device * @dev: the dev pointer associated with the platform device * * Returns: the MSI domain for this device, NULL otherwise */ static struct irq_domain *iort_get_platform_device_domain(struct device *dev) { struct acpi_iort_node *node, *msi_parent = NULL; struct fwnode_handle *iort_fwnode; struct acpi_iort_its_group *its; int i; /* find its associated iort node */ node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT, iort_match_node_callback, dev); if (!node) return NULL; /* then find its msi parent node */ for (i = 0; i < node->mapping_count; i++) { msi_parent = iort_node_map_platform_id(node, NULL, IORT_MSI_TYPE, i); if (msi_parent) break; } if (!msi_parent) return NULL; /* Move to ITS specific data */ its = (struct acpi_iort_its_group *)msi_parent->node_data; iort_fwnode = iort_find_domain_token(its->identifiers[0]); if (!iort_fwnode) return NULL; return irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI); } void acpi_configure_pmsi_domain(struct device *dev) { struct irq_domain *msi_domain; msi_domain = iort_get_platform_device_domain(dev); if (msi_domain) dev_set_msi_domain(dev, msi_domain); } #ifdef CONFIG_IOMMU_API static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev) { struct acpi_iort_node *iommu; struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); iommu = iort_get_iort_node(fwspec->iommu_fwnode); if (iommu && (iommu->type == ACPI_IORT_NODE_SMMU_V3)) { struct acpi_iort_smmu_v3 *smmu; smmu = (struct acpi_iort_smmu_v3 *)iommu->node_data; if (smmu->model == ACPI_IORT_SMMU_V3_HISILICON_HI161X) return iommu; } return NULL; } static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); return (fwspec && fwspec->ops) ? fwspec->ops : NULL; } static inline int iort_add_device_replay(struct device *dev) { int err = 0; if (dev->bus && !device_iommu_mapped(dev)) err = iommu_probe_device(dev); return err; } /** * iort_iommu_msi_get_resv_regions - Reserved region driver helper * @dev: Device from iommu_get_resv_regions() * @head: Reserved region list from iommu_get_resv_regions() * * Returns: Number of msi reserved regions on success (0 if platform * doesn't require the reservation or no associated msi regions), * appropriate error value otherwise. The ITS interrupt translation * spaces (ITS_base + SZ_64K, SZ_64K) associated with the device * are the msi reserved regions. */ int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); struct acpi_iort_its_group *its; struct acpi_iort_node *iommu_node, *its_node = NULL; int i, resv = 0; iommu_node = iort_get_msi_resv_iommu(dev); if (!iommu_node) return 0; /* * Current logic to reserve ITS regions relies on HW topologies * where a given PCI or named component maps its IDs to only one * ITS group; if a PCI or named component can map its IDs to * different ITS groups through IORT mappings this function has * to be reworked to ensure we reserve regions for all ITS groups * a given PCI or named component may map IDs to. */ for (i = 0; i < fwspec->num_ids; i++) { its_node = iort_node_map_id(iommu_node, fwspec->ids[i], NULL, IORT_MSI_TYPE); if (its_node) break; } if (!its_node) return 0; /* Move to ITS specific data */ its = (struct acpi_iort_its_group *)its_node->node_data; for (i = 0; i < its->its_count; i++) { phys_addr_t base; if (!iort_find_its_base(its->identifiers[i], &base)) { int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; struct iommu_resv_region *region; region = iommu_alloc_resv_region(base + SZ_64K, SZ_64K, prot, IOMMU_RESV_MSI); if (region) { list_add_tail(®ion->list, head); resv++; } } } return (resv == its->its_count) ? resv : -ENODEV; } static inline bool iort_iommu_driver_enabled(u8 type) { switch (type) { case ACPI_IORT_NODE_SMMU_V3: return IS_ENABLED(CONFIG_ARM_SMMU_V3); case ACPI_IORT_NODE_SMMU: return IS_ENABLED(CONFIG_ARM_SMMU); default: pr_warn("IORT node type %u does not describe an SMMU\n", type); return false; } } static int arm_smmu_iort_xlate(struct device *dev, u32 streamid, struct fwnode_handle *fwnode, const struct iommu_ops *ops) { int ret = iommu_fwspec_init(dev, fwnode, ops); if (!ret) ret = iommu_fwspec_add_ids(dev, &streamid, 1); return ret; } static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node) { struct acpi_iort_root_complex *pci_rc; pci_rc = (struct acpi_iort_root_complex *)node->node_data; return pci_rc->ats_attribute & ACPI_IORT_ATS_SUPPORTED; } static int iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node, u32 streamid) { const struct iommu_ops *ops; struct fwnode_handle *iort_fwnode; if (!node) return -ENODEV; iort_fwnode = iort_get_fwnode(node); if (!iort_fwnode) return -ENODEV; /* * If the ops look-up fails, this means that either * the SMMU drivers have not been probed yet or that * the SMMU drivers are not built in the kernel; * Depending on whether the SMMU drivers are built-in * in the kernel or not, defer the IOMMU configuration * or just abort it. */ ops = iommu_ops_from_fwnode(iort_fwnode); if (!ops) return iort_iommu_driver_enabled(node->type) ? -EPROBE_DEFER : -ENODEV; return arm_smmu_iort_xlate(dev, streamid, iort_fwnode, ops); } struct iort_pci_alias_info { struct device *dev; struct acpi_iort_node *node; }; static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data) { struct iort_pci_alias_info *info = data; struct acpi_iort_node *parent; u32 streamid; parent = iort_node_map_id(info->node, alias, &streamid, IORT_IOMMU_TYPE); return iort_iommu_xlate(info->dev, parent, streamid); } static void iort_named_component_init(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_named_component *nc; struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); if (!fwspec) return; nc = (struct acpi_iort_named_component *)node->node_data; fwspec->num_pasid_bits = FIELD_GET(ACPI_IORT_NC_PASID_BITS, nc->node_flags); } static int iort_nc_iommu_map(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_node *parent; int err = -ENODEV, i = 0; u32 streamid = 0; do { parent = iort_node_map_platform_id(node, &streamid, IORT_IOMMU_TYPE, i++); if (parent) err = iort_iommu_xlate(dev, parent, streamid); } while (parent && !err); return err; } static int iort_nc_iommu_map_id(struct device *dev, struct acpi_iort_node *node, const u32 *in_id) { struct acpi_iort_node *parent; u32 streamid; parent = iort_node_map_id(node, *in_id, &streamid, IORT_IOMMU_TYPE); if (parent) return iort_iommu_xlate(dev, parent, streamid); return -ENODEV; } /** * iort_iommu_configure_id - Set-up IOMMU configuration for a device. * * @dev: device to configure * @id_in: optional input id const value pointer * * Returns: iommu_ops pointer on configuration success * NULL on configuration failure */ const struct iommu_ops *iort_iommu_configure_id(struct device *dev, const u32 *id_in) { struct acpi_iort_node *node; const struct iommu_ops *ops; int err = -ENODEV; /* * If we already translated the fwspec there * is nothing left to do, return the iommu_ops. */ ops = iort_fwspec_iommu_ops(dev); if (ops) return ops; if (dev_is_pci(dev)) { struct iommu_fwspec *fwspec; struct pci_bus *bus = to_pci_dev(dev)->bus; struct iort_pci_alias_info info = { .dev = dev }; node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX, iort_match_node_callback, &bus->dev); if (!node) return NULL; info.node = node; err = pci_for_each_dma_alias(to_pci_dev(dev), iort_pci_iommu_init, &info); fwspec = dev_iommu_fwspec_get(dev); if (fwspec && iort_pci_rc_supports_ats(node)) fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS; } else { node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT, iort_match_node_callback, dev); if (!node) return NULL; err = id_in ? iort_nc_iommu_map_id(dev, node, id_in) : iort_nc_iommu_map(dev, node); if (!err) iort_named_component_init(dev, node); } /* * If we have reason to believe the IOMMU driver missed the initial * add_device callback for dev, replay it to get things in order. */ if (!err) { ops = iort_fwspec_iommu_ops(dev); err = iort_add_device_replay(dev); } /* Ignore all other errors apart from EPROBE_DEFER */ if (err == -EPROBE_DEFER) { ops = ERR_PTR(err); } else if (err) { dev_dbg(dev, "Adding to IOMMU failed: %d\n", err); ops = NULL; } return ops; } #else int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) { return 0; } const struct iommu_ops *iort_iommu_configure_id(struct device *dev, const u32 *input_id) { return NULL; } #endif static int nc_dma_get_range(struct device *dev, u64 *size) { struct acpi_iort_node *node; struct acpi_iort_named_component *ncomp; node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT, iort_match_node_callback, dev); if (!node) return -ENODEV; ncomp = (struct acpi_iort_named_component *)node->node_data; if (!ncomp->memory_address_limit) { pr_warn(FW_BUG "Named component missing memory address limit\n"); return -EINVAL; } *size = ncomp->memory_address_limit >= 64 ? U64_MAX : 1ULL<memory_address_limit; return 0; } static int rc_dma_get_range(struct device *dev, u64 *size) { struct acpi_iort_node *node; struct acpi_iort_root_complex *rc; struct pci_bus *pbus = to_pci_dev(dev)->bus; node = iort_scan_node(ACPI_IORT_NODE_PCI_ROOT_COMPLEX, iort_match_node_callback, &pbus->dev); if (!node || node->revision < 1) return -ENODEV; rc = (struct acpi_iort_root_complex *)node->node_data; if (!rc->memory_address_limit) { pr_warn(FW_BUG "Root complex missing memory address limit\n"); return -EINVAL; } *size = rc->memory_address_limit >= 64 ? U64_MAX : 1ULL<memory_address_limit; return 0; } /** * iort_dma_setup() - Set-up device DMA parameters. * * @dev: device to configure * @dma_addr: device DMA address result pointer * @dma_size: DMA range size result pointer */ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) { u64 end, mask, dmaaddr = 0, size = 0, offset = 0; int ret; /* * If @dev is expected to be DMA-capable then the bus code that created * it should have initialised its dma_mask pointer by this point. For * now, we'll continue the legacy behaviour of coercing it to the * coherent mask if not, but we'll no longer do so quietly. */ if (!dev->dma_mask) { dev_warn(dev, "DMA mask not set\n"); dev->dma_mask = &dev->coherent_dma_mask; } if (dev->coherent_dma_mask) size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1); else size = 1ULL << 32; ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size); if (ret == -ENODEV) ret = dev_is_pci(dev) ? rc_dma_get_range(dev, &size) : nc_dma_get_range(dev, &size); if (!ret) { /* * Limit coherent and dma mask based on size retrieved from * firmware. */ end = dmaaddr + size - 1; mask = DMA_BIT_MASK(ilog2(end) + 1); dev->bus_dma_limit = end; dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask); *dev->dma_mask = min(*dev->dma_mask, mask); } *dma_addr = dmaaddr; *dma_size = size; ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size); dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? " failed!" : ""); } static void __init acpi_iort_register_irq(int hwirq, const char *name, int trigger, struct resource *res) { int irq = acpi_register_gsi(NULL, hwirq, trigger, ACPI_ACTIVE_HIGH); if (irq <= 0) { pr_err("could not register gsi hwirq %d name [%s]\n", hwirq, name); return; } res->start = irq; res->end = irq; res->flags = IORESOURCE_IRQ; res->name = name; } static int __init arm_smmu_v3_count_resources(struct acpi_iort_node *node) { struct acpi_iort_smmu_v3 *smmu; /* Always present mem resource */ int num_res = 1; /* Retrieve SMMUv3 specific data */ smmu = (struct acpi_iort_smmu_v3 *)node->node_data; if (smmu->event_gsiv) num_res++; if (smmu->pri_gsiv) num_res++; if (smmu->gerr_gsiv) num_res++; if (smmu->sync_gsiv) num_res++; return num_res; } static bool arm_smmu_v3_is_combined_irq(struct acpi_iort_smmu_v3 *smmu) { /* * Cavium ThunderX2 implementation doesn't not support unique * irq line. Use single irq line for all the SMMUv3 interrupts. */ if (smmu->model != ACPI_IORT_SMMU_V3_CAVIUM_CN99XX) return false; /* * ThunderX2 doesn't support MSIs from the SMMU, so we're checking * SPI numbers here. */ return smmu->event_gsiv == smmu->pri_gsiv && smmu->event_gsiv == smmu->gerr_gsiv && smmu->event_gsiv == smmu->sync_gsiv; } static unsigned long arm_smmu_v3_resource_size(struct acpi_iort_smmu_v3 *smmu) { /* * Override the size, for Cavium ThunderX2 implementation * which doesn't support the page 1 SMMU register space. */ if (smmu->model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX) return SZ_64K; return SZ_128K; } static void __init arm_smmu_v3_init_resources(struct resource *res, struct acpi_iort_node *node) { struct acpi_iort_smmu_v3 *smmu; int num_res = 0; /* Retrieve SMMUv3 specific data */ smmu = (struct acpi_iort_smmu_v3 *)node->node_data; res[num_res].start = smmu->base_address; res[num_res].end = smmu->base_address + arm_smmu_v3_resource_size(smmu) - 1; res[num_res].flags = IORESOURCE_MEM; num_res++; if (arm_smmu_v3_is_combined_irq(smmu)) { if (smmu->event_gsiv) acpi_iort_register_irq(smmu->event_gsiv, "combined", ACPI_EDGE_SENSITIVE, &res[num_res++]); } else { if (smmu->event_gsiv) acpi_iort_register_irq(smmu->event_gsiv, "eventq", ACPI_EDGE_SENSITIVE, &res[num_res++]); if (smmu->pri_gsiv) acpi_iort_register_irq(smmu->pri_gsiv, "priq", ACPI_EDGE_SENSITIVE, &res[num_res++]); if (smmu->gerr_gsiv) acpi_iort_register_irq(smmu->gerr_gsiv, "gerror", ACPI_EDGE_SENSITIVE, &res[num_res++]); if (smmu->sync_gsiv) acpi_iort_register_irq(smmu->sync_gsiv, "cmdq-sync", ACPI_EDGE_SENSITIVE, &res[num_res++]); } } static void __init arm_smmu_v3_dma_configure(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_smmu_v3 *smmu; enum dev_dma_attr attr; /* Retrieve SMMUv3 specific data */ smmu = (struct acpi_iort_smmu_v3 *)node->node_data; attr = (smmu->flags & ACPI_IORT_SMMU_V3_COHACC_OVERRIDE) ? DEV_DMA_COHERENT : DEV_DMA_NON_COHERENT; /* We expect the dma masks to be equivalent for all SMMUv3 set-ups */ dev->dma_mask = &dev->coherent_dma_mask; /* Configure DMA for the page table walker */ acpi_dma_configure(dev, attr); } #if defined(CONFIG_ACPI_NUMA) /* * set numa proximity domain for smmuv3 device */ static int __init arm_smmu_v3_set_proximity(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_smmu_v3 *smmu; smmu = (struct acpi_iort_smmu_v3 *)node->node_data; if (smmu->flags & ACPI_IORT_SMMU_V3_PXM_VALID) { int dev_node = pxm_to_node(smmu->pxm); if (dev_node != NUMA_NO_NODE && !node_online(dev_node)) return -EINVAL; set_dev_node(dev, dev_node); pr_info("SMMU-v3[%llx] Mapped to Proximity domain %d\n", smmu->base_address, smmu->pxm); } return 0; } #else #define arm_smmu_v3_set_proximity NULL #endif static int __init arm_smmu_count_resources(struct acpi_iort_node *node) { struct acpi_iort_smmu *smmu; /* Retrieve SMMU specific data */ smmu = (struct acpi_iort_smmu *)node->node_data; /* * Only consider the global fault interrupt and ignore the * configuration access interrupt. * * MMIO address and global fault interrupt resources are always * present so add them to the context interrupt count as a static * value. */ return smmu->context_interrupt_count + 2; } static void __init arm_smmu_init_resources(struct resource *res, struct acpi_iort_node *node) { struct acpi_iort_smmu *smmu; int i, hw_irq, trigger, num_res = 0; u64 *ctx_irq, *glb_irq; /* Retrieve SMMU specific data */ smmu = (struct acpi_iort_smmu *)node->node_data; res[num_res].start = smmu->base_address; res[num_res].end = smmu->base_address + smmu->span - 1; res[num_res].flags = IORESOURCE_MEM; num_res++; glb_irq = ACPI_ADD_PTR(u64, node, smmu->global_interrupt_offset); /* Global IRQs */ hw_irq = IORT_IRQ_MASK(glb_irq[0]); trigger = IORT_IRQ_TRIGGER_MASK(glb_irq[0]); acpi_iort_register_irq(hw_irq, "arm-smmu-global", trigger, &res[num_res++]); /* Context IRQs */ ctx_irq = ACPI_ADD_PTR(u64, node, smmu->context_interrupt_offset); for (i = 0; i < smmu->context_interrupt_count; i++) { hw_irq = IORT_IRQ_MASK(ctx_irq[i]); trigger = IORT_IRQ_TRIGGER_MASK(ctx_irq[i]); acpi_iort_register_irq(hw_irq, "arm-smmu-context", trigger, &res[num_res++]); } } static void __init arm_smmu_dma_configure(struct device *dev, struct acpi_iort_node *node) { struct acpi_iort_smmu *smmu; enum dev_dma_attr attr; /* Retrieve SMMU specific data */ smmu = (struct acpi_iort_smmu *)node->node_data; attr = (smmu->flags & ACPI_IORT_SMMU_COHERENT_WALK) ? DEV_DMA_COHERENT : DEV_DMA_NON_COHERENT; /* We expect the dma masks to be equivalent for SMMU set-ups */ dev->dma_mask = &dev->coherent_dma_mask; /* Configure DMA for the page table walker */ acpi_dma_configure(dev, attr); } static int __init arm_smmu_v3_pmcg_count_resources(struct acpi_iort_node *node) { struct acpi_iort_pmcg *pmcg; /* Retrieve PMCG specific data */ pmcg = (struct acpi_iort_pmcg *)node->node_data; /* * There are always 2 memory resources. * If the overflow_gsiv is present then add that for a total of 3. */ return pmcg->overflow_gsiv ? 3 : 2; } static void __init arm_smmu_v3_pmcg_init_resources(struct resource *res, struct acpi_iort_node *node) { struct acpi_iort_pmcg *pmcg; /* Retrieve PMCG specific data */ pmcg = (struct acpi_iort_pmcg *)node->node_data; res[0].start = pmcg->page0_base_address; res[0].end = pmcg->page0_base_address + SZ_4K - 1; res[0].flags = IORESOURCE_MEM; /* * The initial version in DEN0049C lacked a way to describe register * page 1, which makes it broken for most PMCG implementations; in * that case, just let the driver fail gracefully if it expects to * find a second memory resource. */ if (node->revision > 0) { res[1].start = pmcg->page1_base_address; res[1].end = pmcg->page1_base_address + SZ_4K - 1; res[1].flags = IORESOURCE_MEM; } if (pmcg->overflow_gsiv) acpi_iort_register_irq(pmcg->overflow_gsiv, "overflow", ACPI_EDGE_SENSITIVE, &res[2]); } static struct acpi_platform_list pmcg_plat_info[] __initdata = { /* HiSilicon Hip08 Platform */ {"HISI ", "HIP08 ", 0, ACPI_SIG_IORT, greater_than_or_equal, "Erratum #162001800, Erratum #162001900", IORT_SMMU_V3_PMCG_HISI_HIP08}, /* HiSilicon Hip09 Platform */ {"HISI ", "HIP09 ", 0, ACPI_SIG_IORT, greater_than_or_equal, "Erratum #162001900", IORT_SMMU_V3_PMCG_HISI_HIP09}, { } }; static int __init arm_smmu_v3_pmcg_add_platdata(struct platform_device *pdev) { u32 model; int idx; idx = acpi_match_platform_list(pmcg_plat_info); if (idx >= 0) model = pmcg_plat_info[idx].data; else model = IORT_SMMU_V3_PMCG_GENERIC; return platform_device_add_data(pdev, &model, sizeof(model)); } struct iort_dev_config { const char *name; int (*dev_init)(struct acpi_iort_node *node); void (*dev_dma_configure)(struct device *dev, struct acpi_iort_node *node); int (*dev_count_resources)(struct acpi_iort_node *node); void (*dev_init_resources)(struct resource *res, struct acpi_iort_node *node); int (*dev_set_proximity)(struct device *dev, struct acpi_iort_node *node); int (*dev_add_platdata)(struct platform_device *pdev); }; static const struct iort_dev_config iort_arm_smmu_v3_cfg __initconst = { .name = "arm-smmu-v3", .dev_dma_configure = arm_smmu_v3_dma_configure, .dev_count_resources = arm_smmu_v3_count_resources, .dev_init_resources = arm_smmu_v3_init_resources, .dev_set_proximity = arm_smmu_v3_set_proximity, }; static const struct iort_dev_config iort_arm_smmu_cfg __initconst = { .name = "arm-smmu", .dev_dma_configure = arm_smmu_dma_configure, .dev_count_resources = arm_smmu_count_resources, .dev_init_resources = arm_smmu_init_resources, }; static const struct iort_dev_config iort_arm_smmu_v3_pmcg_cfg __initconst = { .name = "arm-smmu-v3-pmcg", .dev_count_resources = arm_smmu_v3_pmcg_count_resources, .dev_init_resources = arm_smmu_v3_pmcg_init_resources, .dev_add_platdata = arm_smmu_v3_pmcg_add_platdata, }; static __init const struct iort_dev_config *iort_get_dev_cfg( struct acpi_iort_node *node) { switch (node->type) { case ACPI_IORT_NODE_SMMU_V3: return &iort_arm_smmu_v3_cfg; case ACPI_IORT_NODE_SMMU: return &iort_arm_smmu_cfg; case ACPI_IORT_NODE_PMCG: return &iort_arm_smmu_v3_pmcg_cfg; default: return NULL; } } /** * iort_add_platform_device() - Allocate a platform device for IORT node * @node: Pointer to device ACPI IORT node * @ops: Pointer to IORT device config struct * * Returns: 0 on success, <0 failure */ static int __init iort_add_platform_device(struct acpi_iort_node *node, const struct iort_dev_config *ops) { struct fwnode_handle *fwnode; struct platform_device *pdev; struct resource *r; int ret, count; pdev = platform_device_alloc(ops->name, PLATFORM_DEVID_AUTO); if (!pdev) return -ENOMEM; if (ops->dev_set_proximity) { ret = ops->dev_set_proximity(&pdev->dev, node); if (ret) goto dev_put; } count = ops->dev_count_resources(node); r = kcalloc(count, sizeof(*r), GFP_KERNEL); if (!r) { ret = -ENOMEM; goto dev_put; } ops->dev_init_resources(r, node); ret = platform_device_add_resources(pdev, r, count); /* * Resources are duplicated in platform_device_add_resources, * free their allocated memory */ kfree(r); if (ret) goto dev_put; /* * Platform devices based on PMCG nodes uses platform_data to * pass the hardware model info to the driver. For others, add * a copy of IORT node pointer to platform_data to be used to * retrieve IORT data information. */ if (ops->dev_add_platdata) ret = ops->dev_add_platdata(pdev); else ret = platform_device_add_data(pdev, &node, sizeof(node)); if (ret) goto dev_put; fwnode = iort_get_fwnode(node); if (!fwnode) { ret = -ENODEV; goto dev_put; } pdev->dev.fwnode = fwnode; if (ops->dev_dma_configure) ops->dev_dma_configure(&pdev->dev, node); iort_set_device_domain(&pdev->dev, node); ret = platform_device_add(pdev); if (ret) goto dma_deconfigure; return 0; dma_deconfigure: arch_teardown_dma_ops(&pdev->dev); dev_put: platform_device_put(pdev); return ret; } #ifdef CONFIG_PCI static void __init iort_enable_acs(struct acpi_iort_node *iort_node) { static bool acs_enabled __initdata; if (acs_enabled) return; if (iort_node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) { struct acpi_iort_node *parent; struct acpi_iort_id_mapping *map; int i; map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, iort_node, iort_node->mapping_offset); for (i = 0; i < iort_node->mapping_count; i++, map++) { if (!map->output_reference) continue; parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, map->output_reference); /* * If we detect a RC->SMMU mapping, make sure * we enable ACS on the system. */ if ((parent->type == ACPI_IORT_NODE_SMMU) || (parent->type == ACPI_IORT_NODE_SMMU_V3)) { pci_request_acs(); acs_enabled = true; return; } } } } #else static inline void iort_enable_acs(struct acpi_iort_node *iort_node) { } #endif static void __init iort_init_platform_devices(void) { struct acpi_iort_node *iort_node, *iort_end; struct acpi_table_iort *iort; struct fwnode_handle *fwnode; int i, ret; const struct iort_dev_config *ops; /* * iort_table and iort both point to the start of IORT table, but * have different struct types */ iort = (struct acpi_table_iort *)iort_table; /* Get the first IORT node */ iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort, iort->node_offset); iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort, iort_table->length); for (i = 0; i < iort->node_count; i++) { if (iort_node >= iort_end) { pr_err("iort node pointer overflows, bad table\n"); return; } iort_enable_acs(iort_node); ops = iort_get_dev_cfg(iort_node); if (ops) { fwnode = acpi_alloc_fwnode_static(); if (!fwnode) return; iort_set_fwnode(iort_node, fwnode); ret = iort_add_platform_device(iort_node, ops); if (ret) { iort_delete_fwnode(iort_node); acpi_free_fwnode_static(fwnode); return; } } iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node, iort_node->length); } } void __init acpi_iort_init(void) { acpi_status status; /* iort_table will be used at runtime after the iort init, * so we don't need to call acpi_put_table() to release * the IORT table mapping. */ status = acpi_get_table(ACPI_SIG_IORT, 0, &iort_table); if (ACPI_FAILURE(status)) { if (status != AE_NOT_FOUND) { const char *msg = acpi_format_exception(status); pr_err("Failed to get table, %s\n", msg); } return; } iort_init_platform_devices(); } #ifdef CONFIG_ZONE_DMA /* * Extract the highest CPU physical address accessible to all DMA masters in * the system. PHYS_ADDR_MAX is returned when no constrained device is found. */ phys_addr_t __init acpi_iort_dma_get_max_cpu_address(void) { phys_addr_t limit = PHYS_ADDR_MAX; struct acpi_iort_node *node, *end; struct acpi_table_iort *iort; acpi_status status; int i; if (acpi_disabled) return limit; status = acpi_get_table(ACPI_SIG_IORT, 0, (struct acpi_table_header **)&iort); if (ACPI_FAILURE(status)) return limit; node = ACPI_ADD_PTR(struct acpi_iort_node, iort, iort->node_offset); end = ACPI_ADD_PTR(struct acpi_iort_node, iort, iort->header.length); for (i = 0; i < iort->node_count; i++) { if (node >= end) break; switch (node->type) { struct acpi_iort_named_component *ncomp; struct acpi_iort_root_complex *rc; phys_addr_t local_limit; case ACPI_IORT_NODE_NAMED_COMPONENT: ncomp = (struct acpi_iort_named_component *)node->node_data; local_limit = DMA_BIT_MASK(ncomp->memory_address_limit); limit = min_not_zero(limit, local_limit); break; case ACPI_IORT_NODE_PCI_ROOT_COMPLEX: if (node->revision < 1) break; rc = (struct acpi_iort_root_complex *)node->node_data; local_limit = DMA_BIT_MASK(rc->memory_address_limit); limit = min_not_zero(limit, local_limit); break; } node = ACPI_ADD_PTR(struct acpi_iort_node, node, node->length); } acpi_put_table(&iort->header); return limit; } #endif