The 205-pound contest will take place at the UFC 172 pay-per-view event in Baltimore. UFC president Dana White tweeted the news Tuesday.
Johnson (16-4) returns to the Octagon for the first time since the UFC released him following a submission loss to Vitor Belfort in January 2012. During a five-year run with the UFC, Johnson compiled a 7-4 record but consistently struggled to make weight. After coming in heavy for welterweight bouts in 2007 and '09, Johnson moved to middleweight for the Belfort fight, but missed weight again, prompting his release.
Johnson, 29, eventually moved to light heavyweight in August 2012 and has won all six of his fights outside the UFC since his release.
The Southern California-based Davis (12-1) will carry a three-fight win streak into the fight. He hasn't fought since an upset unanimous decision win over Lyoto Machida in August.
ESPN.com currently ranks Davis as the No. 5 light heavyweight in the world.
For Rockhold (11-2), it marks a relatively quick turnaround. The former Strikeforce champion recorded a first-round knockout over Costas Philippou at UFC Fight Night 35 on Jan. 15. The win evened his UFC record at 1-1.
Rockhold made his UFC debut in May, losing in the first round via knockout to Belfort. It was his first setback since November 2007.
Boetsch (17-6) avoided a three-fight losing streak in his last bout, edging C.B. Dollaway via split decision at UFC 166 in October. The former light heavyweight had lost two consecutive bouts prior to the win, to Philippou and Mark Munoz.