How do I compile mips gnu?

I am not even sure my thread title is correct or not. Here is my story. I visited western digital website to check for a new firmware of wdtv live. I found开发者_StackOverflow社区 source code of wdtv live OS is available to download. I downloaded "WDTV GPL Code" on http://support.wdc.com/product/download.asp?groupid=1003&lang=en. I extracted it and...came up with

mips-4.3.tgz
linux_kernel_2.6.22.19-19.tgz

I googled about those two archive and I guess "mips-4.3.tgz" is operating system and "linux_kernel_2.6.22.19-19.tgz" is linux kernel obviously.

In my understanding, I need to have a running linux in order to compile linux kernel. So I assume that I have to install mips-4.3.tgz somehow.

Does anyone have any idea on how to install mips??

While these instructions seem to be geared towards the Android, maybe they can be of some use.