There's nothing written by Knuth that provides a “standard” for what DVI drivers actually do; users are commonly referred to the sources of dvitype, but that doesn't actually specify anything (merely tells you how the utility works).

The DVI standards working group set out to produce a comprehensive specification of what device drivers should do. The present “level 0” is as far as the effort got.

The author is TUG DVI Standards Working Group.