Basically I've done a quick and dirty port of the DSerial lib to DSLinux, which involved changing a few types in the source. I've also had to change the irq handler from libnds to linux kernel. Everything else seemed to compile ok with a few warnings.
The status so far is that I can sucessfully:
dseInit
dseVersion
dseBoot
dseStatus
and the light changes color
There's still loads left to do. I've got to tidy up what I've already got working, implement some kind of firmware loading and then integrate it with the linux char driver layer (*gulp*), which looks daunting to say the least.