Re: [PATCH v4 02/13] dt-bindings: memory: mediatek: Add mt8195 smi sub common

From: Rob Herring
Date: Tue Sep 21 2021 - 16:36:48 EST


On Tue, 14 Sep 2021 19:36:52 +0800, Yong Wu wrote:
> Add the binding for smi-sub-common. The SMI block diagram like this:
>
> IOMMU
> | |
> smi-common
> ------------------
> | .... |
> larb0 larb7 <-max is 8
>
> The smi-common connects with smi-larb and IOMMU. The maximum larbs number
> that connects with a smi-common is 8. If the engines number is over 8,
> sometimes we use a smi-sub-common which is nearly same with smi-common.
> It supports up to 8 input and 1 output(smi-common has 2 output)
>
> Something like:
>
> IOMMU
> | |
> smi-common
> ---------------------
> | | ...
> larb0 sub-common ... <-max is 8
> -----------
> | | ... <-max is 8 too.
> larb2 larb5
>
> We don't need extra SW setting for smi-sub-common, only the sub-common has
> special clocks need to enable when the engines access dram.
>
> If it is sub-common, it should have a "mediatek,smi" phandle to point to
> its smi-common. meanwhile the sub-common only has one gals clock.
>
> Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
> ---
> change note: add "else mediatek,smi: false".
> ---
> .../mediatek,smi-common.yaml | 28 +++++++++++++++++++
> 1 file changed, 28 insertions(+)
>

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>