[ex-aws-dude]

That is interesting, do you ever find bugs in the hardware itself?

Is there some big spec document or ISA that you follow when implementing the driver?

Also I'm curious is it easier to write a driver for the modern "lower level" APIs like vulkan/dx12?

[tyfighter]

Hardware bugs can be found during chip bring-up within the first couple of months back from the fab, but since I've worked in this area I've never actually seen a bug that couldn't be worked around. They happen, but they're rare and I've never experienced a chip needing a respin because of a bug.

There is documentation, but it's not as well organized as you might imagine. Documentation is usually only necessary when implementing new features, and the resulting code doesn't change often. There are also multiple instruction sets as there are a bunch of little processors you need to control.

Vulkan/DX12 aren't really "low-level" APIs. They're "low overhead", and honestly, no. Their code base is just as large and complicated, if not more so, than OpenGL/DX11.