Which greater Telugu poet lived at the court of Krishnadeva raya?

not one. 8 poets are there namely

Ashtadiggajas (అష్టదిగ్గజులు)

They are

Allasani Peddana, Dhurjati, Nandi Thimmana, Madayyagari Mallana and Ayyalaraju Ramabhadrudu from the Rayalaseema region.

Tenali Ramakrishna hailed from the Guntur district of Andhra Pradesh