Re: [RFC v6 3/4] tests/qtest/libqos: Add SMMUv3 helper library

[Fabiano Rosas <farosas@suse.de>]

Tao Tang <tangtao1634@phytium.com.cn> writes:

> Introduce qos-smmuv3, a reusable library for SMMUv3-related qtest
> operations. This module encapsulates common tasks like:
>
> - SMMUv3 initialization (enabling, configuring command/event queues)
> - Stream Table Entry (STE) and Context Descriptor (CD) setup
> - Multi-level page table construction (L0-L3 for 4KB granules)
> - Support for Stage 1, Stage 2, and nested translation modes
> - Could be easily extended to support multi-space testing infrastructure
>     (Non-Secure, Secure, Root, Realm)
>
> The library provides high-level abstractions that allow test code to
> focus on IOMMU behavior validation rather than low-level register
> manipulation and page table encoding. Key features include:
>
> - Automatic memory allocation for translation structures with proper
>     alignment
> - Helper functions to build valid STEs/CDs for different translation
>     scenarios
> - Page table walkers that handle address offset calculations per
>     security space
> - Command queue management for SMMU configuration commands
>
> This infrastructure is designed to be used by iommu-testdev-based tests
> and future SMMUv3 test suites, reducing code duplication and improving
> test maintainability.
>
> Signed-off-by: Tao Tang <tangtao1634@phytium.com.cn>

To the best of my ability:

Reviewed-by: Fabiano Rosas <farosas@suse.de>