Hello, last year a first version of this series was submitted to add support for IOMMU for AP806, including workaround for accessing ARM SMMU 64bit registers[1]. For the record, AP-806 can't access SMMU registers with 64bit width, this patches split the readq/writeq for 32bit access, due to erratanum #582743. Based on the feedback from Robin Murphy, I also add code ensuring that we won't try to use AArch64 format with 32 bits acces. It was also discussed to not use compatible but propertu to support this workaround. I agree to make this change if needed, but for now I would like to have a feedback on the current code to know if it is acceptable if there is still potential issue. The series was tested on a vanilla v5.1 kernel, and without the series, an USB stick was not detected under QEMU whereas with this series it worked as expected. Greogry [1]: https://lkml.org/lkml/2018/10/15/373 Gregory CLEMENT (1): arm64: dts: marvell: armada-ap806: add smmu support Hanna Hawa (3): iommu/arm-smmu: Introduce wrapper for writeq/readq iommu/arm-smmu: Workaround for Marvell Armada-AP806 SoC erratum #582743 dt-bindings: iommu/arm,smmu: add compatible string for Marvell Documentation/arm64/silicon-errata.txt | 2 + .../devicetree/bindings/iommu/arm,smmu.txt | 1 + arch/arm64/boot/dts/marvell/armada-ap806.dtsi | 17 +++++ drivers/iommu/arm-smmu.c | 74 ++++++++++++++++--- 4 files changed, 83 insertions(+), 11 deletions(-) -- 2.20.1
