Re: [PATCH] ARM: dts: imx: Set default tuning step for imx7d usdhc0

From: Fabio Estevam
Date: Fri Jul 21 2023 - 20:16:18 EST


Hi Xiaolei,

On Fri, Jul 21, 2023 at 8:21 PM Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx> wrote:
>
> If the tuning step is not set, the tuning step is set to 1.
> For some sd cards, the following Tuning timeout will occur,
> so set the default tuning step.
>
> Tuning failed, falling back to fixed sampling clock
> mmc0: Tuning failed, falling back to fixed sampling clock
>
> Fixes: 1e336aa0c025 ("mmc: sdhci-esdhc-imx: correct the tuning start tap and step setting")
> Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/nxp/imx/imx7d-sdb.dts | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/boot/dts/nxp/imx/imx7d-sdb.dts b/arch/arm/boot/dts/nxp/imx/imx7d-sdb.dts
> index 75f1cd14bea1..d7396fbfcaf8 100644
> --- a/arch/arm/boot/dts/nxp/imx/imx7d-sdb.dts
> +++ b/arch/arm/boot/dts/nxp/imx/imx7d-sdb.dts
> @@ -493,6 +493,7 @@ &usdhc1 {
> vmmc-supply = <&reg_sd1_vmmc>;
> wakeup-source;
> keep-power-in-suspend;
> + fsl,tuning-step = <2>;

I wondering if this should be a imx7s.dtsi property instead.

NXP vendor kernel passes:

fsl,tuning-step = <2>;
fsl,tuning-start-tap = <20>;

https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm/boot/dts/imx7s.dtsi#L1216-L1217

Bough? Any suggestions?

Thanks