As of today there's now mainline Coreboot support for handling the "MinnowMax" board. The MinnowBoard MAX features an Intel Atom E3815/E3825 "Bay Trail" Atom SoC (the model depends upon the two versions of the MinnowBoard MAX), 1GB/2GB of system memory, Gigabit ethernet, GPIO pins, and other development functionality. The E3815/1GB board version sells for $99 USD while the E3825/2GB version sells for $139. Those hearing about the MinnowBoard MAX can read about the single-board computer at MinnowBoard.org. The footprint of the computer is about the size of a Raspberry Pi, as with the plethora of ARM development boards.
With today's Coreboot support there is the ability to boot from Serial ATA and USB 2.0/3.0, but booting from SD storage isn't yet supported. The S3 suspend/resume support is also borked when using Coreboot. Setting up Coreboot on the board requires reconfiguring the Intel Bay Trail Firmware Support Package (FSP).
This new Coreboot hardware enablement was done by Sage Electronic Engineering. In another Coreboot commit today by the company, "Bakersport" board support was added as a variant of Intel's Bayley Bay board.
Those curious about other boards supported by Coreboot can see the Coreboot Wiki for a full listing.