Re: [PATCH V4 4/4] arm64: dts: qcom: sm8550: Remove SDR104/SDR50 broken capabilities

[Sarthak Garg]

On 8/5/2025 6:38 PM, Konrad Dybcio wrote:
> On 8/5/25 11:59 AM, Dmitry Baryshkov wrote:
> > On Tue, Aug 05, 2025 at 02:49:29PM +0530, Sarthak Garg wrote:
> > > On 8/1/2025 2:32 PM, Krzysztof Kozlowski wrote:
> > > > On 01/08/2025 10:45, Sarthak Garg wrote:
> > > > > The kernel now handles level shifter limitations affecting SD card
> > > > > modes, making it unnecessary to explicitly disable SDR104 and SDR50
> > > > > capabilities in the device tree.
> > > > >
> > > > > However, due to board-specific hardware constraints particularly related
> > > > > to level shifter in this case the maximum frequency for SD High-Speed
> > > > > (HS) mode must be limited to 37.5 MHz to ensure reliable operation of SD
> > > > > card in HS mode. This is achieved using the max-sd-hs-frequency property
> > > > > in the board DTS.
> > > > >
> > > > > Signed-off-by: Sarthak Garg <quic_sartgarg@xxxxxxxxxxx>
> > > > > ---
> > > > >    arch/arm64/boot/dts/qcom/sm8550-hdk.dts                     | 1 +
> > > > >    arch/arm64/boot/dts/qcom/sm8550-mtp.dts                     | 1 +
> > > > >    arch/arm64/boot/dts/qcom/sm8550-sony-xperia-yodo-pdx234.dts | 1 +
> > > > >    arch/arm64/boot/dts/qcom/sm8550.dtsi                        | 3 ---
> >
> > You missed several devices which use SM8550. Please fix that.
>
> I would be in favor of making this addition in the SoC dtsi and removing/
> altering it on a case by case basis, since as I explained in the threads
> of previous revisions, the fix for the limitation is additional on-board
> hardware
>
> Konrad

@Krzysztof Kozlowski please let me know your view on placement of the 
max-sd-hs-frequency
DT property in SOC dtsi as per above comment.

Best regards,
Sarthak