Please help me to identify this ramdisk format

I've a question about an embedded Linux ramdisk.image for virtex4 with 405 PPC, I read the ramdisk is usually a CPIO archive, but when trying to unpack it with CPIO and get the inner files I have an error, also the header of the partition doesn't look to be a CPIO one. I've also attached the kernel if necessary, but I'm only interested to know which king of ramdisk image it is and how to properly extract all of the files. I'm also interested to unterstand which is the structure for such a partion and how it has been created.

here's the link to the zipped archive with the image and kernel https://www.sendspace.com/file/0se934

Thanks in advance

Hi:

I downloaded the zip and tried to open it in Libre Office and all I had was a blank white page.

Maybe paste on pastebin or tiny paste.
http://pastebin.com/

Hello and welcome to LQ.

Wonder if it has been zipped? The FreeRTOS comes in either a windows self extracting zip or a plain zip format.

I forget the command that might help. Think it is "file" to help id the file properties.

Just downloaded and tried again.

bash-4.3$ unzip upl.zip
Archive:  upl.zip
  inflating: upl/gzipped-kernel.bin  
  inflating: upl/gzippedramdisk.bin  
bash-4.3$

Looking at the properties and the permission's of upl/gzipped-kernel.bin & upl/gzippedramdisk.bin they are read only.

Still can't open them.
Okular can't find a plugin to open it. Libre Office opens to a blank page.
Ark opens them and shows that it's uncompressed but won't open it so I can read it.

What am I missing jefro?

$ file file.bin

You might also try hexedit to see what the headers / meta data looks like.

bash-4.3$ ls
gzipped-kernel.bin  gzippedramdisk.bin
bash-4.3$ unzip gzippe-kernel.bin
unzip:  cannot find or open gzippe-kernel.bin, gzippe-kernel.bin.zip or gzippe-kernel.bin.ZIP.
bash-4.3$ unzip gzipped-kernel.bin 
Archive:  gzipped-kernel.bin
  End-of-central-directory signature not found.  Either this file is not
  a zipfile, or it constitutes one disk of a multi-part archive.  In the
  latter case the central directory and zipfile comment will be found on
  the last disk(s) of this archive.
unzip:  cannot find zipfile directory in one of gzipped-kernel.bin or
        gzipped-kernel.bin.zip, and cannot find gzipped-kernel.bin.ZIP, period.
bash-4.3$

Gave it my best try:-