flash a ROM without Windows/USB

[gdanko]

I have a Rockchip 2918-based tablet with a busted USB port which is need of a firmware upgrade. However, the only method I've seen for upgrading these Rockchip units requires both USB *and* Windows, neither of which I have.

Has anyone created an "update.zip" method for installing ROMs to Rockchip units? Thanks in advance.

 

[gdanko]

I have the official firmware for this unit in the rar file but it's a massive "img" file. Does anyone know the format of these img files? I am wondering if I can convert the contents to an update.zip.

One thing I was thinking is to make an update.zip that takes my dd files and does something like:
flash_image boot boot.img
flash_image recovery recovery.img
flash_image system system.img

And so forth. There HAS to be a way to update this unit without using Windows/USB.