bari wrote:
There are several i945 + Atom boards available. This way you can develop and test Atom on a working chipset and then work on the US15W.
In my opinion, porting US15W may not be worthwhile, since it doesn't support the SPI bus which would allow use of SPI NOR flash. US15W supports FWH which Intel has already obsoleted, although It may have contracted with third parties to supply FWH devices for this chip set.
Also, this chipset almost requires an embedded controller to handle power and translate between FWH and SPI bus to support SPI NOR devices. Intel does offer a CPLD solution that avoids the use of the embedded controller, but the CPLD would only permit reading of the SPI NOR flash and absolutely no writing of it.
The US15W also has it own microcode updating that the BIOS/firmware must support.
The i945/ICH7M would be a far better final target for an Atom chipset and has none of the above mentioned issues. Of course you would need to use Diamondville Atom rather Silverthorne Atom in this case.
Good luck with your Poulsbo (US15W) port, assuming you are willing to spend 6-9 months on it. It could be more or less than that depending on the number of people working on it and their firmware experience.
Sincerely,
Ken Fuchs