Microsoft are using Intel/Altera FPGAs in the datacenter, and not likely for mass produced devices like this.
While it is possible they are using FPGAs for the Hololens Processing Unit, I seriously doubt it. The FPGA needed to exceed the performance of a high-end mobile GPU (OpenCL/CUDA for Deep Learning/AI) would have an excessive power consumption for a mobile device.
Another factor is that higher end FPGAs are expensive ($200+ wholesale) and typically cost thousands each, and not suited to a mass produced consumer device.
As for who made this HPU, I'd say AMD helped design it and GlobalFoundries (or maybe TSMC) are doing the production.
I have a friend at Intel who works in the AR division and their comment to me is that in one way or another all AR/MR glasses are running Intel silicon. I asked them specifically, does that include, Hololens, Apple's Project, and a couple others specifically, and they answered in the affirmative. YMMV though.
While it is possible they are using FPGAs for the Hololens Processing Unit, I seriously doubt it. The FPGA needed to exceed the performance of a high-end mobile GPU (OpenCL/CUDA for Deep Learning/AI) would have an excessive power consumption for a mobile device.
Another factor is that higher end FPGAs are expensive ($200+ wholesale) and typically cost thousands each, and not suited to a mass produced consumer device.
As for who made this HPU, I'd say AMD helped design it and GlobalFoundries (or maybe TSMC) are doing the production.