Creating emmc flashable image from a sd card image

I was able to create a working image on a Jetson NX development kit that uses sd card storage. We would like to extract the image into a .img that can be flashed into a 16Gb emmc production module of the Jetson NX. Thanks.

You can use dd to get the APP partition out from your sdcard.

Please can you clarify? There is a number of issues I see here. Would the size of the SD card partition (i.e. 256Gb) not affect the size of the generated .img file? If it does, how do I use dd properly to handle this? Secondly, would the resulting .img the flashable by simply replacing placing it in the “bootloader/” directory in the BSP folder; putting the production module in recovery mode; and running “sudo ./flash.sh -r jetson-xavier-nx-devkit-emmc mmcblk0p1”. Please can suggest clearer steps, thanks.

Hi,

Actually, it is not a very common request so I didn’t try this before either.

Since sdcard only has APP partition in use, you can only get APP partition from it. The rest of bootloader and other software still requires to get from the BSP directory. And of course you can only use the same size equal to the emmc.

Note that you’d probably have to modify some content in “/boot”, e.g., the extlinux.conf might be pointing to the SD card rootfs, or the device tree might be named and be fore the SD card model instead of the eMMC model. If your dd saved copy is copied to “Linux_for_Tegra/bootloader/system.img”, then the “flash -r” method would simply copy this during flash, plus install the correct boot environment for the model named in the command (e.g., the target of “jetson-xavier-nx-devkit-emmc”).

1 Like

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.