Reserved Memory Regions(RMR) associated with an IOMMU may be described either through ACPI tables or DT in systems with devices that require a unity mapping or bypass for those regions in IOMMU drivers.
Introduce a generic interface so that IOMMU drivers can retrieve and set up necessary mappings. Signed-off-by: Shameer Kolothum <[email protected]> --- drivers/iommu/dma-iommu.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/dma-iommu.h | 7 +++++++ include/linux/iommu.h | 16 ++++++++++++++++ 3 files changed, 59 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 0cbcd3fc3e7e..d73768ecdd1a 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -166,6 +166,42 @@ void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list) } EXPORT_SYMBOL(iommu_dma_get_resv_regions); +/** + * iommu_dma_get_rmrs - Retrieve Reserved Memory Regions(RMRs) associated + * with a given IOMMU + * @iommu_fwnode: fwnode associated with IOMMU + * @list: RMR list to be populated + * + */ +int iommu_dma_get_rmrs(struct fwnode_handle *iommu_fwnode, + struct list_head *list) +{ + return 0; +} +EXPORT_SYMBOL(iommu_dma_get_rmrs); + +struct iommu_rmr *iommu_dma_alloc_rmr(u64 base, u64 length, + u32 *ids, int num_ids) +{ + struct iommu_rmr *rmr; + int i; + + rmr = kzalloc(struct_size(rmr, ids, num_ids), GFP_KERNEL); + if (!rmr) + return NULL; + + INIT_LIST_HEAD(&rmr->list); + rmr->base_address = base; + rmr->length = length; + rmr->num_ids = num_ids; + + for (i = 0; i < num_ids; i++) + rmr->ids[i] = ids[i]; + + return rmr; +} +EXPORT_SYMBOL(iommu_dma_alloc_rmr); + static int cookie_init_hw_msi_region(struct iommu_dma_cookie *cookie, phys_addr_t start, phys_addr_t end) { diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h index 2112f21f73d8..8900ccbc9e6a 100644 --- a/include/linux/dma-iommu.h +++ b/include/linux/dma-iommu.h @@ -37,6 +37,9 @@ void iommu_dma_compose_msi_msg(struct msi_desc *desc, void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list); +int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list); +struct iommu_rmr *iommu_dma_alloc_rmr(u64 base, u64 length, + u32 *ids, int num_ids); #else /* CONFIG_IOMMU_DMA */ struct iommu_domain; @@ -78,5 +81,9 @@ static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_he { } +int iommu_dma_get_rmrs(struct fwnode_handle *iommu, struct list_head *list); +{ + return 0; +} #endif /* CONFIG_IOMMU_DMA */ #endif /* __DMA_IOMMU_H */ diff --git a/include/linux/iommu.h b/include/linux/iommu.h index b95a6f8db6ff..e43c4e8084e7 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -592,6 +592,22 @@ struct iommu_sva { struct device *dev; }; +/** + * struct iommu_rmr - Reserved Memory Region details per IOMMU + * @list: Linked list pointers to hold RMR region info + * @base_address: base address of Reserved Memory Region + * @length: length of memory region + * @num_ids: number of associated device IDs + * @ids: associated device IDs + */ +struct iommu_rmr { + struct list_head list; + phys_addr_t base_address; + u64 length; + unsigned int num_ids; + u32 ids[]; +}; + int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, const struct iommu_ops *ops); void iommu_fwspec_free(struct device *dev); -- 2.17.1 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
