On some platforms msi parent address regions have to be excluded from normal IOVA allocation in that they are detected and decoded in a HW specific way by system components and so they cannot be considered normal IOVA address space. Add a helper function that retrieves ITS address regions - the msi parent - through IORT device <-> ITS mappings and reserves it so that these regions will not be translated by IOMMU and will be excluded from IOVA allocations. Signed-off-by: Shameer Kolothum [lorenzo.pieralisi@arm.com: updated commit log/added comments] Signed-off-by: Lorenzo Pieralisi --- drivers/acpi/arm64/iort.c | 97 ++++++++++++++++++++++++++++++++++++++-- drivers/irqchip/irq-gic-v3-its.c | 3 +- include/linux/acpi_iort.h | 7 ++- 3 files changed, 102 insertions(+), 5 deletions(-) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 9565d57..876c0e1 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -39,6 +39,7 @@ struct iort_its_msi_chip { struct list_head list; struct fwnode_handle *fw_node; + phys_addr_t base_addr; u32 translation_id; }; @@ -136,14 +137,16 @@ typedef acpi_status (*iort_find_node_callback) static DEFINE_SPINLOCK(iort_msi_chip_lock); /** - * iort_register_domain_token() - register domain token and related ITS ID - * to the list from where we can get it back later on. + * 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, struct fwnode_handle *fw_node) +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; @@ -153,6 +156,7 @@ int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node) 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); @@ -481,6 +485,24 @@ int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id) 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; + bool match = false; + + 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; + match = true; + break; + } + } + spin_unlock(&iort_msi_chip_lock); + + return match ? 0 : -ENODEV; +} + /** * iort_dev_find_its_id() - Find the ITS identifier for a device * @dev: The device. @@ -639,6 +661,73 @@ int iort_add_device_replay(const struct iommu_ops *ops, struct 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 reserved regions on success (0 if no associated msi + * regions), appropriate error value otherwise. The ITS interrupt + * translation space(ITS_base + 0x010000) associated with the device + * are the msi reserved regions. + */ +int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) +{ + struct acpi_iort_its_group *its; + struct acpi_iort_node *node, *its_node = NULL; + int i, resv = 0; + + node = iort_find_dev_node(dev); + if (!node) + return -ENODEV; + + /* + * 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. + */ + if (dev_is_pci(dev)) { + u32 rid; + + pci_for_each_dma_alias(to_pci_dev(dev), __get_pci_rid, &rid); + its_node = iort_node_map_id(node, rid, NULL, IORT_MSI_TYPE); + } else { + for (i = 0; i < node->mapping_count; i++) { + its_node = iort_node_map_platform_id(node, NULL, + IORT_MSI_TYPE, i); + 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; +} #else static inline const struct iommu_ops *iort_fwspec_iommu_ops(struct iommu_fwspec *fwspec) @@ -646,6 +735,8 @@ const struct iommu_ops *iort_fwspec_iommu_ops(struct iommu_fwspec *fwspec) static inline int iort_add_device_replay(const struct iommu_ops *ops, struct device *dev) { return 0; } +int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) +{ return -ENODEV; } #endif static int iort_iommu_xlate(struct device *dev, struct acpi_iort_node *node, diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index e8d8934..19d1ff6 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -3197,7 +3197,8 @@ static int __init gic_acpi_parse_madt_its(struct acpi_subtable_header *header, return -ENOMEM; } - err = iort_register_domain_token(its_entry->translation_id, dom_handle); + err = iort_register_domain_token(its_entry->translation_id, res.start, + dom_handle); if (err) { pr_err("ITS@%pa: Unable to register GICv3 ITS domain token (ITS ID %d) to IORT\n", &res.start, its_entry->translation_id); diff --git a/include/linux/acpi_iort.h b/include/linux/acpi_iort.h index 8d3f0bf..182a577 100644 --- a/include/linux/acpi_iort.h +++ b/include/linux/acpi_iort.h @@ -26,7 +26,8 @@ #define IORT_IRQ_MASK(irq) (irq & 0xffffffffULL) #define IORT_IRQ_TRIGGER_MASK(irq) ((irq >> 32) & 0xffffffffULL) -int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node); +int iort_register_domain_token(int trans_id, phys_addr_t base, + struct fwnode_handle *fw_node); void iort_deregister_domain_token(int trans_id); struct fwnode_handle *iort_find_domain_token(int trans_id); #ifdef CONFIG_ACPI_IORT @@ -38,6 +39,7 @@ /* IOMMU interface */ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *size); const struct iommu_ops *iort_iommu_configure(struct device *dev); +int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head); #else static inline void acpi_iort_init(void) { } static inline u32 iort_msi_map_rid(struct device *dev, u32 req_id) @@ -52,6 +54,9 @@ static inline void iort_dma_setup(struct device *dev, u64 *dma_addr, static inline const struct iommu_ops *iort_iommu_configure(struct device *dev) { return NULL; } +static inline +int iort_iommu_msi_get_resv_regions(struct device *dev, struct list_head *head) +{ return -ENODEV; } #endif #endif /* __ACPI_IORT_H__ */ -- 1.9.1