[PATCH v12 1/3] ACPI/IORT: Add msi address regions reservation helper
Lorenzo Pieralisi
lorenzo.pieralisi at arm.com
Fri Dec 15 02:29:10 PST 2017
On Thu, Dec 14, 2017 at 04:09:55PM +0000, Shameer Kolothum wrote:
> 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. The function checks for the smmu model number and
> only applies the msi reservation if the platform requires it.
>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi at huawei.com>
> ---
> drivers/acpi/arm64/iort.c | 111 +++++++++++++++++++++++++++++++++++++--
> drivers/irqchip/irq-gic-v3-its.c | 3 +-
> include/linux/acpi_iort.h | 7 ++-
> 3 files changed, 116 insertions(+), 5 deletions(-)
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index 95255ec..e2f7bdd 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;
> };
>
> @@ -161,14 +162,16 @@ 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;
>
> @@ -178,6 +181,7 @@ 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);
> @@ -581,6 +585,24 @@ 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;
> + 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.
> @@ -766,6 +788,24 @@ static inline bool iort_iommu_driver_enabled(u8 type)
> }
>
> #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;
> +
> + 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 iommu_fwspec *fwspec)
> {
> @@ -782,6 +822,69 @@ static inline int iort_add_device_replay(const struct iommu_ops *ops,
>
> 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 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 < dev->iommu_fwspec->num_ids; i++) {
> + its_node = iort_node_map_id(iommu_node,
> + dev->iommu_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;
> +}
> #else
> static inline const struct iommu_ops *iort_fwspec_iommu_ops(
> struct iommu_fwspec *fwspec)
> @@ -789,6 +892,8 @@ static inline const struct iommu_ops *iort_fwspec_iommu_ops(
> 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 0; }
> #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 4039e64..d4cff12 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -3450,7 +3450,8 @@ 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 2f7a292..38cd77b 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 0; }
> #endif
>
> #endif /* __ACPI_IORT_H__ */
> --
> 1.9.1
>
>
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