Here is Hermann Hauser, a co-founder of Acorn Computers, and a character been played in the movie, speaking about ARM. Admittedly, this is a long 3 hrs video, but thanks to the charming personality of Mr. Hauser, it is 3 hours of non-stop stories including a funny story of founding the company and their first customer, how nobody wanted to buy ARM at first, and subsequent development of ARM. Interestingly, a few times he referred to ARM as "my chip", perhaps having a right to do so, being at management positions at Acorn and later companies and being involved in taking ARM where it is now. Enjoy!
"Oral history of Hermann Hauser" from the Computer History Museum: