The GetMode() function is not used as of XFree86 1.3; its place in the vgaVideoChipRec should be initialized to `NoopDDA'.
At some point in the future, this function will be used to enable the server and/or a standalone program using the server's driver libraries to do interactive video mode adjustments. This function will read the SVGA registers and fill in a DisplayModeRec structure with the current video mode.