Hi Joseph, On Thu, Dec 4, 2025 at 4:12 AM Joseph Guo (OSS) <[email protected]> wrote:
> Hi Fabio, > > USDHC2 is for SD card and its initial stage is at u-boot. > The IO voltage switch from 3.3v to 1.8v need extra 8ms time on some > platform. I also tested without this delay, SD card can work as SD3.0 on > imx91 frdm platform. > > I prefer to remain this to avoid potential risk as 91evk 93evk 93frdm > all remain this property. I understand that a few NXP boards use this fsl,signal-voltage-switch-extra-delay-ms property. Linux does not use it. U-Boot should not use it either. Whatever solution the kernel applies to provide this delay, let's use it in U-Boot. I would really appreciate it if you could investigate this with the NXP folks and try to remove this custom property from U-Boot. Let's keep the U-Bot dts files as close as possible with Linux. I appreciate your understanding and cooperation. Thanks
