From: Fangyu Yu The RISC-V IOMMU can optionally support Svpbmt page-based memory types in its page table format. When present,the generic page table code can use this capability to encode memory attributes (e.g. MMIO vs normal memory) in PTEs. Reviewed-by: Jason Gunthorpe Reviewed-by: Anup Patel Reviewed-by: Guo Ren Reviewed-by: Nutty Liu Reviewed-by: Kevin Tian Signed-off-by: Fangyu Yu --- drivers/iommu/riscv/iommu.c | 2 ++ include/linux/generic_pt/common.h | 4 ++++ 2 files changed, 6 insertions(+) diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c index a31f50bbad35..6c324f9fdc53 100644 --- a/drivers/iommu/riscv/iommu.c +++ b/drivers/iommu/riscv/iommu.c @@ -1268,6 +1268,8 @@ static struct iommu_domain *riscv_iommu_alloc_paging_domain(struct device *dev) cfg.common.features = BIT(PT_FEAT_SIGN_EXTEND) | BIT(PT_FEAT_FLUSH_RANGE) | BIT(PT_FEAT_RISCV_SVNAPOT_64K); + if (iommu->caps & RISCV_IOMMU_CAPABILITIES_SVPBMT) + cfg.common.features |= BIT(PT_FEAT_RISCV_SVPBMT); domain->riscvpt.iommu.nid = dev_to_node(iommu->dev); domain->domain.ops = &riscv_iommu_paging_domain_ops; diff --git a/include/linux/generic_pt/common.h b/include/linux/generic_pt/common.h index fc5d0b5edadc..2683e5b38998 100644 --- a/include/linux/generic_pt/common.h +++ b/include/linux/generic_pt/common.h @@ -188,6 +188,10 @@ enum { * Support the 64k contiguous page size following the Svnapot extension. */ PT_FEAT_RISCV_SVNAPOT_64K = PT_FEAT_FMT_START, + /* + * Support Svpbmt extension: encode page-based memory type (PBMT) in PTEs. + */ + PT_FEAT_RISCV_SVPBMT, }; -- 2.50.1