Re: [PATCH v2 5/5] iommu/mediatek: Always tlb_flush_all when each PM resume

[AngeloGioacchino Del Regno]

Il 08/12/21 13:07, Dafna Hirschfeld ha scritto:
> From: Yong Wu <yong.wu@xxxxxxxxxxxx>
>
> Prepare for 2 HWs that sharing pgtable in different power-domains.
>
> When there are 2 M4U HWs, it may has problem in the flush_range in which
> we get the pm_status via the m4u dev, BUT that function don't reflect the
> real power-domain status of the HW since there may be other HW also use
> that power-domain.
>
> DAM allocation is often done while the allocating device is runtime
> suspended. In such a case the iommu will also be suspended and partial
> flushing of the tlb will not be executed.
> Therefore, we add a tlb_flush_all in the pm_runtime_resume to make
> sure the tlb is always clean.
>
> In other case, the iommu's power should be active via device
> link with smi.
>
> Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
> [move the call to mtk_iommu_tlb_flush_all to the bottom of resume cb, improve doc/log]
> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>