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The hardware-recommended software workaround is to >> issue every CFGI/TLBI command (each followed by CMD_SYNC) twice, and >> that infrastructure is already in place behind >> arm_smmu_erratum_repeat_tlbi_cfgi_key. >> >> Neither IDR nor IIDR flags this Tegra264-specific bug, so hardware >> detection is not possible. Tegra264 is device-tree-only (no ACPI/IORT >> support) and already has a dedicated "nvidia,tegra264-smmu" compatible, >> so DT-probe is the only viable detection path. >> >> Enable the workaround on instances matching the existing >> "nvidia,tegra264-smmu" compatible by calling static_branch_enable() on >> arm_smmu_erratum_repeat_tlbi_cfgi_key. Document the erratum in >> Documentation/arch/arm64/silicon-errata.rst. >> >> Signed-off-by: Ashish Mhetre > Reviewed-by: Nicolin Chen > > Sashiko pointed out a concern at PATCH-3 regarding the static key: > https://sashiko.dev/#/patchset/20260709095613.831769-1-amhetre%40nvidia.com > > It's a false positive. But perhaps we could fold in an inline note; > it'd belong to the missing description that I commented in PATCH-2. > > Nicolin Ack, I will address this in v6. Thanks, Ashish Mhetre