[PATCH v6 00/33] MT8192 IOMMU support

Tomasz Figa tfiga at chromium.org
Fri Jan 29 06:27:56 EST 2021


Hi Yong,

On Mon, Jan 11, 2021 at 07:18:41PM +0800, Yong Wu wrote:
> This patch mainly adds support for mt8192 Multimedia IOMMU and SMI.
> 
> mt8192 also is MTK IOMMU gen2 which uses ARM Short-Descriptor translation
> table format. The M4U-SMI HW diagram is as below:
> 
>                           EMI
>                            |
>                           M4U
>                            |
>                       ------------
>                        SMI Common
>                       ------------
>                            |
>   +-------+------+------+----------------------+-------+
>   |       |      |      |       ......         |       |
>   |       |      |      |                      |       |
> larb0   larb1  larb2  larb4     ......      larb19   larb20
> disp0   disp1   mdp    vdec                   IPE      IPE
> 
> All the connections are HW fixed, SW can NOT adjust it.
> 
> Comparing with the preview SoC, this patchset mainly adds two new functions:
> a) add iova 34 bits support.
> b) add multi domains support since several HW has the special iova
> region requirement.
> 
> change note:
> v6:a) base on v5.11-rc1. and tlb v4:
>       https://lore.kernel.org/linux-mediatek/20210107122909.16317-1-yong.wu@mediatek.com/T/#t 
>    b) Remove the "domain id" definition in the binding header file.
>       Get the domain from dev->dma_range_map.
>       After this, Change many codes flow.
>    c) the patchset adds a new common file(mtk_smi-larb-port.h).
>       This version changes that name into mtk-memory-port.h which reflect 
>       its file path. This only changes the file name. no other change.
>       thus I keep all the Reviewed-by Tags.
>       (another reason is that we will add some iommu ports unrelated with
>        smi-larb)
>    d) Refactor the power-domain flow suggestted by Tomasz.
>    e) Some other small fix. use different oas for different soc; Change the
>    macro for 34bit iova tlb flush.
> 

Thanks for the fixes.

I still think the concept of dma-ranges is not quire right for the
problem we need to solve here, but it certainly works for the time being
and it's possible to remove it in a follow up patch, so I'm fine with
merging this as is.

Reviewed-by: Tomasz Figa <tfiga at chromium.org>

I'll comment on my suggestion for a replacement for the dma-ranges that
doesn't need hardcoding arbitrary address ranges in DT in a separate
reply.

Best regards,
Tomasz



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