If you are having trouble mounting a JFFS2 file system on a Compulab cm-x270 module, you may have a device that has a NAND flash with 16KiB eraseblocks. All of the devices I have personally used to date have had 128KiB eraseblocks, but I just helped a cm-x270 user through some flash issues and after much pain discovered the eraseblock size was 16KiB on his module. A variable has been added to the cm-x270.conf file in OE to set the eraseblock size that can be overridden in your local.conf file if you are using OpenEmbedded to generate jffs2 images:
Compulab cm-x270 NAND flash eraseblock sizes
- by Cliff Brake