Hi Jean-Philippe, On 09/03/2018 02:28 PM, Jean-Philippe Brucker wrote: > On 31/08/2018 15:07, Auger Eric wrote: >>> Since the ioctl will be used to combine invalidations (invalidate both >>> ATC and TLB with a single call), we need an additional ASID field for >>> the SMMU - ATC is invalidated by PASID, TLB by ASID. I used to call it >>> "tag", but I'm leaning towards "arch_id" now >>> (http://www.linux-arm.org/git?p=linux-jpb.git;a=commitdiff;h=40fdef74816dd8d8d113100b9e0162fab4cec28d) >> >> I aknowledge I am not crystal clear about that. for a given iommu_domain >> don't you have a single asid. Can't you retrieve the asid from the >> iommu_domain/arm_smmu_domain/arm_smmu_s1_cfg/arm_smmu_ctx_desc.asid? >> Here again I am confused bout the dual iommu_domain/struct device >> parameters. > > In nested mode, ASIDs are allocated by the guest and written into the CD > table. Even if there is a single CD it will still be private to the > guest. When receiving the invalidation, the host could walk the CD > tables to retrieve the ASID, but it's not guaranteed to be here anymore: > the guest could well clear a CD before sending the invalidate command. That's fully correct. I messed up at the beginning with this asid and that's perfectly true the asid needs to be passed. I will respin accordingly. > >> I have another trouble while doing the QEMU integration. >> When the guests does an NH_ALL, this propagates an invalidation on the >> whole IPA range and we must discriminate that from regular NH_VA calls. >> How would you encode the NH_ALL with this API? > > I think that translates to an invalidate-all for the domain: > > struct tlb_iommu_invalidate_info info = { > .hdr.type = IOMMU_INV_TYPE_TLB, > .granularity = IOMMU_INV_GRANU_DOMAIN_ALL_PASID, OK > }; > > Reading the spec again, I though the API was missing a way to encode > TLBI_NH_VAA, invalidate a range for all ASIDs. Although it feels > contrived, we could represent it with the following: > > struct tlb_iommu_invalidate_info info = { > .hdr.type = IOMMU_INV_TYPE_TLB, > .granularity = IOMMU_INV_GRANU_PAGE_PASID, > .flags = IOMMU_INVALIDATE_GLOBAL_PAGE, > .addr = ... OK Also what about CMD_CFI_CD(_ALL) propagation. Is it an IOMMU_INV_TYPE_PASID invalidation? Thanks Eric > }; > > Thanks, > Jean >
