Hi,
Doing a quick google this comes up, where it seems someone else looked at this CPU before:
https://www.mail-archive.com/search?l=coreboot@coreboot.org&q=subject:"\[coreboot\]+Re\%3A+About+support+for+my+netbook"&o=newest&f=1
It seems there's no support for this CPU/chipset in coreboot, ao at the very least you'd have to update and adapt some very old pineview code to support cedarview, assuming it's possible. No idea whether an FSP would be required, but I'd guess not considering the age of the chipset? (not to mention, if no FSP is available then you can't use it whether any other method is possible or not)
Even assuming you could somehow scrape together CPU and chipset support, you'd then need to go through the arduous process of porting to the motherboard itself, adapting coreboot to match it's wiring.
As for U-Boot vs Coreboot, Coreboot+payload is primarily targeted at x86 at the moment (sorry Ron!) whereas I've seen U-Boot more commonly on ARM/MIPS/PowerPC embedded systems. My understanding is that both do much the same job however, though in different ways with different features.
Sincerely,
-Matthew Bradley