The phone interview consisted of just questions about my past work experience. Then got called for an on-site interview. The interview lasted 5 hrs with 30 min interviews with 10 people, including one with HR. Most of the questions were about my past experience here as well. Included a lot of drawing on the white board to explain the architecture of software I had worked on. There were some programming questions as well, which were quite simple, like code for fibonacci series and factorial using both recursive and non-recursive methods, counting the number of 1s in a variable, writing code for a circular buffer. Also had questions on OS, like memory management, interrupt handling, preemption etc. I thought I did well, but did not receive an offer.