Secondary dimension (cached) api call?

I need to get all visits split by page URI AND some secondary dimension - campaign OR deviceType.

The problem is, that i have milions of visits every month, so i cannot count it on the fly, i need some calculated precalculated - archived - data.

I do have cron that calculates archives, so i have quick access to deviceType stats and page Uri stats. But i need to get device type statistics for some given page (or pivot for multiple given pages). Is it possible?

I could use segments - one segment per one page URI, and then do archiving for such segments and then call device type per theese URL, that seems too complicated for me (and i would need hundrets of segments). Any better way?