21.12.9.2 Filter Available Objects

Explicit clock pins for the design is the default value. To identify any other pins in the design as the generated clock source pins, select Filter available objects - Pin Type as Explicit clocks, Potential clocks, Input ports, All Pins, All Nets, Pins on clock network, or Nets in clock network . You can also use the Filter to filter the generated clock source pin name in the displayed list.