Coming Soon: An Open-Source, Reverse-Engineered Mali GPU Driver

An anonymous reader writes "Next month at FOSDEM there will be an announcement of a fully open-source and reverse-engineered ARM Mali graphics driver for Android / Linux. This driver, according to Phoronix, is said to support OpenGL ES and other functionality from reverse engineering the official ARM Linux driver. Will this mark a change for open-source graphics drivers on ARM, just as the Radeon did for x86 Linux?"

propreitary

[it0]

I know they keep the drivers proprietary to keep their special 3d chip tricks to themselves, but can't you just feed it tables of vectors and vectors and be done with it? Why do you need such a low level access that apparantly shows all their company secrets?

Before all you say performance! My question would be , really?

Re:propreitary

[TheRaven64]

Increasingly, GPUs are just general-purpose processors that are optimised for a very different set of algorithms to CPUs (i.e. stream-based access to memory instead of lots of locality of reference, primarily floating-point vector data instead of integer data, and few branches instead of about one every 7 instructions on average for CPUs). This means that a GPU driver is increasingly just a compiler. There is a lot less of a reason to keep the details of the hardware instruction set secret, because, as with something like ARM or x86, the valuable bit is how it's implemented, not the instruction set itself. This also means that there's a lot of incentive to keep the in-house drivers secret, because the difference between a bad compiler and a good one can easily be a factor of two in terms of performance with real code and sometimes a lot more.

Re:It's a big challenge to reverse engineer

[TheRaven64]

Add to that, most modern GPUs also have a variety of coprocessors for things like H.264 decoding. These are quite often licensed as IP cores from a third party, so a company like nVidia or AMD may not even legally be allowed to provide you with their programming interfaces. To make life even more fun for reverse engineers, they don't document where they licensed these coprocessor cores from anywhere, so it's generally very hard to work out who to contact with a request for documentation. This is why open source drivers tend to miss off some of the features of the proprietary ones: once you've reverse engineered the GPU, there's still a load of other stuff left...