And, we have the mystery solved, but not a good answer for you.
AMD sold that technology to Qualcomm in 2009. If you search for AMD sells hand held graphics you'll find all kinds of information.
Qualcomm Acquires Handheld Graphics and Multimedia Assets from AMD
So, no answer here, but now at least we know why, and where, perhaps, you may be able to get some help.
Thanks for the treasure hunt! Sorry it came up empty for you. If nothing else it helps me meet LOTS of people all over the company.
You are correct, it was moved to Qualcomm and renamed to "Adreno". With ATI/AMD, it was the Imageon Z430, with Qualcomm, it became the Adreno 200.
For even more trivia, the ATI/AMD Imageon design was originally grew out of IP that was bought from BitBoys:
BitBoys - Wikipedia, the free encyclopedia
If one is using Linux, it should be possible to use the Open Source "Freedreno" code in Mesa with the Imageon Z430/Adreno 200. Freedreno is a reverse engineered graphics stack for the Adreno GPUs. It does require a relatively new kernel though to the best of my knowledge.