Q: where does cmdline come from in 2.6?

["P. Christeas" <p_christ@xxxxxx>]

I am porting to a new platform. My board gives me a custom bootloader, which 
boots the kernel from a std uncompressed ELF image. 
In MIPS, how do I find the original cmdline the bootloader provides me? I know 
there is one. In 2.6.15-rc it seems to get overriden by some build-time line.
Can you please give me a hint..