On Fri, Aug 15, 2025 at 05:03:55PM +0800, Peng Fan wrote:
> From: Richard Zhu <hongxing.zhu@nxp.com>
>
> M.2 device only can be enabled after all Power Rails reach their minimum
> operating voltage (PCI Express M.2 Specification r5.1 3.1.4 Power-up
> Timing). Set a delay equal to the max value of Tsettle in m2 regulator.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
> arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> index feee6da65d37cae7413b09216014d6fe2b76b032..82e183dc581012a7c5be3d2bf749463d0a8a360d 100644
> --- a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> +++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
> @@ -136,6 +136,13 @@ reg_m2_pwr: regulator-m2-pwr {
> regulator-max-microvolt = <3300000>;
> gpio = <&i2c7_pcal6524 20 GPIO_ACTIVE_HIGH>;
> enable-active-high;
> + /*
> + * M.2 device only can be enabled(W_DISABLE1#) after all Power
> + * Rails reach their minimum operating voltage (PCI Express M.2
> + * Specification r5.1 3.1.4 Power-up Timing).
> + * Set a delay equal to the max value of Tsettle here.
> + */
> + startup-delay-us = <5000>;
> };
>
> reg_pcie0: regulator-pcie {
>
> --
> 2.37.1
>