Re: [PATCH v6 02/11] arm64: dts: imx95-19x19-evk: Add supports-clkreq property to PCIe M.2 port

Frank Li
2025-10-31T19:37:39Z

On Wed, Oct 15, 2025 at 11:04:19AM +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#.
>
> imx95-19x19-evk matches this requirement, so add supports-clkreq to
> allow PCIe device enter ASPM L1 Sub-State.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

> arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> index 9f968feccef67..0f470d3eb9af4 100644
> --- a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> +++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> @@ -542,6 +542,7 @@ &pcie0 {
> pinctrl-names = "default";
> reset-gpio = <&i2c7_pcal6524 5 GPIO_ACTIVE_LOW>;
> vpcie-supply = <&reg_pcie0>;
> + supports-clkreq;
> status = "okay";
> };
>
> --
> 2.37.1
>