A little late to the party, but I also have a libreboot C201, and have successfully installed mainline Debian on a USB drive connected to it. I'm going to put up a comprehensive guide + shell scripts in December when I'm on break from school, but until then, check out these links:

https://github.com/atopuzov/c201/blob/master/debian-install....

https://archlinuxarm.org/platforms/armv7/rockchip/asus-chrom...

The main thing I haven't gotten working yet is the touchpad. For wifi, I'm using an atheros dongle with open firmware.