Re: GPU-specific code with no GPU-specific features?

>
> On nonfree firmware, two points which I hope address the concern.
>
> The GNU/Linux backend does not in fact require a GPU or any
> nonfree firmware. It runs on Mesa, which is free software, and it
> works on Mesa's software rasterizer (llvmpipe), which executes
> entirely on the CPU.


This answer misses the point. First of all, with llvmpipe you get an
emulated GPU, which is slow as hell. Nobody wants that. It may be useful
for debugging and tests. Secondly, the "graphics drivers" needed by modern
graphics cards that are included in Mesa are free software, and the low
level drivers for cards from the "big three" manufacturers are free
software too, if you choose your card wisely.

What Richard is talking about is the non-free firmware that has to be
loaded into the graphics card to be reasonably usable, unlocking hardware
acceleration, and this applies to all modern cards from Nvidia, AMD, and
Intel too. The firmware is often also digitally signed, and the signature
is checked by the card. This means a clean-room implementation of the
firmware based on reverse engineering the hardware is not possible.