Int 15 Fn DA12  U - Ami Pci Bios - V1.00.05.ax1 - ???                      [-]

   AX = DA12h
   CL = subfunction
       00h ???
       01h ???
       02h get ???
       03h ???
       04h ???
   ???

Return: CF clear if successful
       ???
   CF set on error
       AH = error code (86h unsupported subfunction)
Desc:  ??? performs various manipulations on system chipset registers

Notes: subfunctions 00h and 01h are NOPs in protected and V86 modes due to
     a test of MSW bit 0
   subfunctions 00h-02h always return success