These two driver versions have differently named Kconfig options. The article above documents some of those differences, but we do not know if there may be other differences as well.
To summarize: We are having some difficulty making sure that the documentation we read is for the latest version of the driver. So far we have relied on the Kconfig program to verify that we are using only the supported config options for the Linux kernel.
Is there additional documentation (like the article referenced above) that can help us understand how to correctly configure the DRM driver so that we get a /dev/fb device?