Re: [PATCH v2 0/6] Add support for Translation Buffer Units

[Bryan O'Donoghue]

On 18/11/2023 04:27, Georgi Djakov wrote:
> The TCUs (Translation Control Units) and TBUs (Translation Buffer
> Units) are key components of the MMU-500. Multiple TBUs are connected
> to a single TCU over an interconnect. Each TBU contains a TLB that
> caches page tables. The MMU-500 implements a TBU for each connected
> master, and the TBU is designed, so that it is local to the master.
>
> The Qualcomm SDM845 platform has an implementation of the SMMU-500,
> that has multiple TBUs. A DT schema is added to describe the resources
> for each TBU (register space, power-domains, interconnects and clocks).
>
> The TBU driver will manage the resources and allow the system to
> operate the TBUs during a context fault to obtain details by doing
> s1 inv, software + hardware page table walks etc. This is implemented
> with ATOS/eCATs as the ATS feature is not supported. Being able to
> query the TBUs is useful for debugging various hardware/software
> issues on these platforms.
>
> v2:
> - Improve DT binding description, add full example. (Konrad)
> - Drop Qcom specific stuff from the generic binding. (Rob)
> - Unconditionally try to populate subnodes. (Konrad)
> - Improve TBU driver commit text, remove memory barriers. (Bjorn)
> - Move TBU stuff into separate file. Make the driver builtin.
> - TODO: Evaluate whether to keep TBU support as a separate driver
>    or just instantiate things from qcom_smmu_impl_init()
>
> v1: https://lore.kernel.org/r/20231019021923.13939-1-quic_c_gdjako@xxxxxxxxxxx

What is your suggested way to test this series ?

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bod