Re: [PATCH v6 03/11] arm64: dts: imx8mm-evk: Add supports-clkreq property to PCIe M.2 port

[Frank Li]

On Wed, Oct 15, 2025 at 11:04:20AM +0800, Richard Zhu wrote:
> According to PCIe r6.1, sec 5.5.1.
>
> The following rules define how the L1.1 and L1.2 substates are entered:
> Both the Upstream and Downstream Ports must monitor the logical state of
> the CLKREQ# signal.
>
> Typical implement is using open drain, which connect RC's clkreq# to
> EP's clkreq# together and pull up clkreq#.
>
> imx8mm-evk matches this requirement, so add supports-clkreq to allow
> PCIe device enter ASPM L1 Sub-State.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> ---

Reviewed-by: Frank Li <Frank.Li@xxxxxxx>

>  arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> index ff7ca20752309..6eab8a6001dbf 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> @@ -542,6 +542,7 @@ &pcie0 {
>  	assigned-clock-parents = <&clk IMX8MM_SYS_PLL2_50M>,
>  				 <&clk IMX8MM_SYS_PLL2_250M>;
>  	vpcie-supply = <&reg_pcie0>;
> +	supports-clkreq;
>  	status = "okay";
>  };
>
> --
> 2.37.1
>