[PATCH 1/4] dt-bindings: mediatek: add mediatek,infracfg phandle

Rob Herring robh at kernel.org
Wed Jul 15 16:51:20 EDT 2020


On Thu, Jul 02, 2020 at 05:37:17PM +0800, Miles Chen wrote:
> Add a description for mediatek,infracfg. We can check if 4GB mode
> is enable by reading it instead of checking the unexported
> symbol "max_pfn".
> 
> This is a step towards building mtk_iommu as a kernel module.

You determined this before without DT, so it is an OS problem and 
shouldn't need a DT update.

I'd assume there's only one instance of the node mediatek,infracfg 
points to, so just search for it if you want to get the info from DT.


> 
> Cc: Yong Wu <yong.wu at mediatek.com>
> Signed-off-by: Miles Chen <miles.chen at mediatek.com>
> ---
>  Documentation/devicetree/bindings/iommu/mediatek,iommu.txt | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt b/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
> index ce59a505f5a4..a7881deabcca 100644
> --- a/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
> +++ b/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt
> @@ -74,6 +74,8 @@ Required properties:
>  - mediatek,larbs : List of phandle to the local arbiters in the current Socs.
>  	Refer to bindings/memory-controllers/mediatek,smi-larb.txt. It must sort
>  	according to the local arbiter index, like larb0, larb1, larb2...
> +- mediatek,infracfg: a phandle to infracfg. It is used to confirm if 4GB mode is set.
> +	It is an optional property, add it when the SoC have 4g mode.
>  - iommu-cells : must be 1. This is the mtk_m4u_id according to the HW.
>  	Specifies the mtk_m4u_id as defined in
>  	dt-binding/memory/mt2701-larb-port.h for mt2701, mt7623
> -- 
> 2.18.0



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