Davis attended Stevenson High School in Michigan. He was a first team all-state selection by multiple media outlets his senior year including Detroit Free Press. As a senior Davis tallied 58 tackles, six sacks, two blocked field goals, one interception and a touchdown. He led Stevenson to the state championship game his senior year.
Davis redshirted in 2010 as a freshman at Iowa. In 2011 he participated in six games but was slowed by injuries as he only recorded two tackles. Davis started to emerge as a force on defense in 2012 as he played in 11 games and tallied 14 tackles including 1.5 tackles for loss and a fumble recovery.
Phil Steele named Davis a pre-season second team All-Big Ten selection in 2013 and he did not disappoint, starting all 13 games at DT and recording 42 tackles. 11 of his 42 tackles were solo stops. He earned his first start of his career in the season opener against Northern Illinois and finished the game with four tackles. Davis notched four tackles for loss on the season and 1.5 sacks. The coaches named Davis to their All-Big Ten second team following the season and the media made him an honorable mention.