> My idea is not to hard code the locations in the drivers per-se, but 
> rather to have compile time macros which might adjust the locations 
> appropriately.  Something like this:
> 
> #ifdef AU1550
> #define   USB_BASE   <someval>
> #else
> #define   USB_BASE   <someval>
> #endif

I would be better to just make USB_BASE itself a config(8) option.
Or even better, make it a locator for the device that needs to
know the value -- if possible.

> The point is, different evaluation boards are going to need different 
> kernels.
> 
> And given that, having run-time selection for a bunch of options seems 
> silly.

Depends on your target application.

	Regards,
		-- Jachym Holecek