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    "msgid": "<1504167642-14922-1-git-send-email-xieyisheng1@huawei.com>",
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    "date": "2017-08-31T08:20:36",
    "name": "[RFC,0/6] Add platform device SVM support for ARM SMMUv3",
    "submitter": {
        "id": 72263,
        "url": "http://patchwork.ozlabs.org/api/people/72263/?format=api",
        "name": "Yisheng Xie",
        "email": "xieyisheng1@huawei.com"
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            "date": "2017-08-31T08:20:36",
            "name": "Add platform device SVM support for ARM SMMUv3",
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        "From": "Yisheng Xie <xieyisheng1@huawei.com>",
        "To": "<jean-philippe.brucker@arm.com>",
        "Subject": "[RFC PATCH 0/6] Add platform device SVM support for ARM SMMUv3",
        "Date": "Thu, 31 Aug 2017 16:20:36 +0800",
        "Message-ID": "<1504167642-14922-1-git-send-email-xieyisheng1@huawei.com>",
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        "Cc": "mark.rutland@arm.com, devicetree@vger.kernel.org,\n\tlorenzo.pieralisi@arm.com, \n\tlv.zheng@intel.com, will.deacon@arm.com, joro@8bytes.org,\n\tliubo95@huawei.com, rjw@rjwysocki.net, robert.moore@intel.com,\n\tlinux-kernel@vger.kernel.org, \n\tlinux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org,\n\trobh+dt@kernel.org, hanjun.guo@linaro.org, xieyisheng@huawei.com,\n\tsudeep.holla@arm.com, chenjiankang1@huawei.com, devel@acpica.org,\n\trobin.murphy@arm.com, linux-arm-kernel@lists.infradead.org,\n\tlenb@kernel.org",
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    "content": "Jean-Philippe has post a patchset for Adding PCIe SVM support to ARM SMMUv3:\nhttps://www.spinics.net/lists/arm-kernel/msg565155.html\n\nBut for some platform devices(aka on-chip integrated devices), there is also\nSVM requirement, which works based on the SMMU stall mode.\nJean-Philippe has prepared a prototype patchset to support it:\ngit://linux-arm.org/linux-jpb.git svm/stall\n\nWe tested this patchset with some fixes on a on-chip integrated device. The\nbasic function is ok, so I just send them out for review, although this\npatchset heavily depends on the former patchset (PCIe SVM support for ARM\nSMMUv3), which is still under discussion.\n\nPatch Overview:\n*1 to 3 prepare for device tree or acpi get the device stall ability and pasid bits\n*4 is to realise the SVM function for platform device\n*5 is fix a bug when test SVM function while SMMU donnot support this feature\n*6 avoid ILLEGAL setting of STE and CD entry about stall\n\nAcctually here, I also have a question about SVM on SMMUv3:\n\n1. Why the SVM feature on SMMUv3 depends on BTM feature? when bind a task to device,\n   it will register a mmu_notify. Therefore, when a page range is invalid, we can\n   send TLBI or ATC invalid without BTM?\n\n2. According to ACPI IORT spec, named component specific data has a node flags field\n   whoes bit0 is for Stall support. However, it do not have any field for pasid bit.\n   Can we use other 5 bits[5:1] for pasid bit numbers, so we can have 32 pasid bit for\n   a single platform device which should be enough, because SMMU only support 20 bit pasid\n\n3. Presently, the pasid is allocate for a task but not for a context, if a task is trying\n   to bind to 2 device A and B:\n     a) A support 5 pasid bits\n     b) B support 2 pasid bits\n     c) when the task bind to device A, it allocate pasid = 16\n     d) then it must be fail when trying to bind to task B, for its highest pasid is 4.\n   So it should allocate a single pasid for a context to avoid this?\n\n\nJean-Philippe Brucker (3):\n  dt-bindings: document stall and PASID properties for IOMMU masters\n  iommu/of: Add stall and pasid properties to iommu_fwspec\n  iommu/arm-smmu-v3: Add SVM support for platform devices\n\nYisheng Xie (3):\n  ACPI: IORT: Add stall and pasid properties to iommu_fwspec\n  iommu/arm-smmu-v3: fix panic when handle stall mode irq\n  iommu/arm-smmu-v3: Avoid ILLEGAL setting of STE.S1STALLD and CD.S\n\n Documentation/devicetree/bindings/iommu/iommu.txt |  13 ++\n drivers/acpi/arm64/iort.c                         |  20 ++\n drivers/iommu/arm-smmu-v3.c                       | 230 ++++++++++++++++++----\n drivers/iommu/of_iommu.c                          |  11 +\n include/acpi/actbl2.h                             |   5 +\n include/linux/iommu.h                             |   2 +\n 6 files changed, 244 insertions(+), 37 deletions(-)\n\n--\n1.7.12.4"
}