Help about simulation of prescaler!

You can do a time domain analysis (e.g. Voltage vs. Time), using a signal at the input of the prescaler and verify the output of the prescaler.
In your simulation increase step-by-step the frequency of the input signal until the output waveform degrades and the level is below the spec.

Thanks! Are there any other methods? I remember some paper mentioned cascading 3 D-flipflops to form a ring oscillator, I want to know more about this or methods like this.