Probably related following Leslau 1956: 247 and EDG 218. See also zändəro ‘this year, the current year’ (AED 1655).
The – apparently iconic (descriptive) – reduplication *dār- dār- (or *dār- dawr-), attested in both Akkadian and early NWS (Ugaritic, Hebrew, Aramaic), may go back to PS.