Re: [PATCH] arm64: dts: qcom: sm8650: set ufs as dma coherent

[Dmitry Baryshkov]

On Tue, Oct 07, 2025 at 08:53:44PM +0200, Neil Armstrong wrote:
> The UFS device is ovbiously dma coherent like the other IOMMU devices
> like usb, mmc, ... let's fix this by adding the flag.
> 
> To be sure an extensive test has been performed to be sure it's
> safe, as downstream uses this flag for UFS as well.
> 
> As an experiment, I checked how the dma-coherent could impact
> the UFS bandwidth, and it happens the max bandwidth on cached
> write is slighly highter (up to 10%) while using less cpu time
> since cache sync/flush is skipped.
> 
> Fixes: 10e024671295 ("arm64: dts: qcom: sm8650: add interconnect dependent device nodes")
> Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> ---
>  arch/arm64/boot/dts/qcom/sm8650.dtsi | 2 ++
>  1 file changed, 2 insertions(+)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>


-- 
With best wishes
Dmitry