How do I flash an image to emmc on rsb-3720?

I have experience flashing images built with imx-image-full to SD cards.
However, I’m not sure how to flash an image to emmc.
Which part of the wiki does this fall under?

Also, do you know how to make it a read-only file system except for /etc and /home/root?
I’m in the process of looking into this using yocto kirkstone’s overrayfs and overrayfs-etc based on the following site.

Please check the wiki user guide: Reflash EMMC from Boot SD CARD
Yocto Linux BSP Ver.C User Guide for iMX8 series -Yocto 4.0 - ESS-WIKI (

Hi @Jems_Cheng
Thank you for your information.
I didn’t think there was a way to flash it on another wiki.

It can reference the Yocto menu to create a Read-only Root Filesystem.
For areas with write access, that can reference 30.3.

Data written in /tmp or /var will be volatile.
I forgot to mention that the written data must also be retained even after the power is turned off.
Also, the data may be rewritten while the power is on.

According to the Linux file system hierarchy standard, regardless of whether rootfs is set to read-only, the data stored in the /tmp directory may be deleted every time the system is started.

You want to write to a rootfs (partition) that has been set to read-only, which is a conflicting operation. I think it can only be written after you set up read/write, or it can add an extra place to store the retained data. The following example creates mmcblk1p3 for writing and persisting data in a read-only rootfs.