Looked at one way DGCGCD is just another variation on C modal, and could in fact be regarded as an Open C tuning.
However the absence of both the tonic and the dominant in the bass,and the preponderance of G's and D's would incline me to thinking that a more realistic assessmant of this tuning would be Open G with suspended fourths.
What you have here in fact is a first cousin to DADGAD, except that the root (tonic) note is G instead of D.
Fascinating stuff. I only wish I still had the time to play around with all these tunings ....