The OpenChrome DRM driver was making progress while James Simmons was developing it a few years back, but since he left the project, it's been left to bit rot. It will take a lot of work even to get this previously "good" code back to working on the latest Linux 4.x mainline kernels given how DRM core interfaces have evolved in recent times.
Last month Kevin Brace called for resuming the VIA/OpenChrome KMS/DRM driver development and was trying to get some experienced DRM driver developers to help out. No one ended up offering their support and some even suggested he restart development from scratch while Kevin has taken it upon himself to figure out how to get this DRM driver into shape.
This weekend Kevin Brace wrote a very lengthy mailing list post where he ultimately says he's trying to get this DRM driver into shape with hopes of mainlining it one day. He hasn't yet got the driver building on Linux 4.x kernels but is currently using Linux 3.19 atop Lubuntu 14.04 on his VIA systems. Aside from making the driver compatible with the mainline code, he's hoping to add DRI2/EXA acceleration support.
Kevin mentioned in the email that he estimates it won't be until at least around the Linux 4.15 kernel (~2018) when the code will hopefully be in a state for talking about merging it to mainline. Given how many OpenChrome developers have come and gone, hopefully he'll remain committed to getting this open-source VIA x86 graphics driver into shape.