P2010/P2020 H/W spec describes that Max SYSCLK frequency is 100MHz. Generically when user inputs 100MHz clock, actual clock speed become more faster. I think P2010/P2020 has enough margin for faster SYSCLK as long as I use up to 100MHz oscillator. Is my understanding correct?
Yes, your understanding is correct. As long as you use 100MHz oscillator it should be fine.