I have an atlas of Dual parabaloid maps with convolution for glossy reflections. So mipmaps generated by my self.
In PVRTexToolGUI you can set external file to each mip level by hands.
I would like to know is it possible to set external mipmaps files from command line?
Sadly there is not interface to supply custom mipmaps to the command-line version of PVRTexTool .
I have filed it as a feature request #66390 so we can look into adding this functionality in the near future.