From: Thierry Reding <treding@xxxxxxxxxx> Hi, this is a set of patches that is the result of earlier discussions regarding early identity mappings that are needed to avoid SMMU faults during early boot. The goal here is to avoid early identity mappings altogether and instead postpone the need for the identity mappings to when devices are attached to the SMMU. This works by making the SMMU driver coordinate with the memory controller driver on when to start enforcing SMMU translations. This makes Tegra behave in a more standard way and pushes the code to deal with the Tegra-specific programming into the NVIDIA SMMU implementation. Compared to the original version of these patches, I've split the preparatory work into a separate patch series because it became very large and will be mostly uninteresting for this audience. Patch 1 provides a mechanism to program SID overrides at runtime. Patch 2 updates the ARM SMMU device tree bindings to include the Tegra186 compatible string as suggested by Robin during review. Patches 3 and 4 create the fundamentals in the SMMU driver to support this and also make this functionality available on Tegra186. Patch 5 hooks the ARM SMMU up to the memory controller so that the memory client stream ID overrides can be programmed at the right time. Patch 6 extends this mechanism to Tegra186 and patches 7-9 enable all of this through device tree updates. Patch 10 (that was included in earlier version to show how SMMU will be enabled for display controllers) has been dropped for now while waiting for the identity mappings support to land. The end result is that various peripherals will have SMMU enabled, while the display controllers will keep using passthrough, as initially set up by firmware. Once the device tree bindings have been accepted and the SMMU driver has been updated to create identity mappings for the display controllers, they can be hooked up to the SMMU and the code in this series will automatically program the SID overrides to enable SMMU translations at the right time. Will, Krzysztof: as discussed, it'd be best if Krzysztof picked up patch 1 into the memory controller tree on top of v3 of the driver unification series I sent out earlier today and then sent out a PR for Will to merge and apply patches 2-6. I can then take patches 7-9 in via the Tegra tree since there are no hard dependencies. Changes in v3: - move hunk from patch 4 to patch 5 to preserve bisectibility Changes in v2: - split off the preparatory work into a separate series (that needs to be applied first) - address review comments by Robin Thierry Thierry Reding (9): memory: tegra: Implement SID override programming dt-bindings: arm-smmu: Add Tegra186 compatible string iommu/arm-smmu: Implement ->probe_finalize() iommu/arm-smmu: tegra: Detect number of instances at runtime iommu/arm-smmu: tegra: Implement SID override programming iommu/arm-smmu: Use Tegra implementation on Tegra186 arm64: tegra: Use correct compatible string for Tegra186 SMMU arm64: tegra: Hook up memory controller to SMMU on Tegra186 arm64: tegra: Enable SMMU support on Tegra194 .../devicetree/bindings/iommu/arm,smmu.yaml | 11 ++- arch/arm64/boot/dts/nvidia/tegra186.dtsi | 4 +- arch/arm64/boot/dts/nvidia/tegra194.dtsi | 86 ++++++++++++++++++ drivers/iommu/arm/arm-smmu/arm-smmu-impl.c | 3 +- drivers/iommu/arm/arm-smmu/arm-smmu-nvidia.c | 90 +++++++++++++++---- drivers/iommu/arm/arm-smmu/arm-smmu.c | 13 +++ drivers/iommu/arm/arm-smmu/arm-smmu.h | 1 + drivers/memory/tegra/mc.c | 9 ++ drivers/memory/tegra/tegra186.c | 72 +++++++++++++++ include/soc/tegra/mc.h | 3 + 10 files changed, 269 insertions(+), 23 deletions(-) -- 2.31.1
