Heavy BS and Death By Pull Ups Workout

Only have an hour to workout, shower and get back to the office. Gotta do something quick.

Warmup:
3 rounds:
10 second samson stretch each leg
10 back extensions
10 GHDs
10 push ups

WOD:
Back squat x10 - 225, 275, 315
Death by pull ups: With a continuously running clock, do one pull-up the first minute, two pull-ups the second minute, three the third, and so on and so forth until you are unable to complete the prescribed number of reps in the given minute.

All rounds unbroken. My palm ripped open so I stopped...

11 rounds + 3