NVIDIA's Open-Source Plans For Maxwell With Nouveau
First of all, if you missed it, checkout the Phoronix review of the NVIDIA GeForce GTX 750 Ti with testing under Ubuntu Linux. This first Maxwell GM107 graphics card is an excellent performer for the mid-range space and comes in at just $150 USD. It's wonderful in raw performance but when looking at the performance-per-Watt it's an even better bargain with just having a 60 Watt TDP.
The GTX 750 series works great with the NVIDIA 334 Linux driver series, but what about open-source driver support? As I wrote in my conclusion to the GTX 750 Ti review, "Nouveau is still catching up with its re-clocking / power management support for several generations and until it's there for Maxwell the overall OpenGL performance will be limited due to being stuck to running at the boot GPU core/memory frequencies and the power efficiency will be disappointing. Your best bet in the months ahead for using the GeForce GTX 750 Ti 'Maxwell' on the Linux desktop will certainly be with NVIDIA's official binary graphics driver."
When writing that article I wasn't sure if NVIDIA would end up contributing open-source Nouveau patches themselves, do a documentation drop, do nothing at all, or something else. I've now heard from a NVIDIA Linux contact about their approach to open-source Maxwell support.
NVIDIA is sending out a GeForce GTX 750 graphics card to one of the lead Nouveau driver developers. Beyond supplying the sample hardware, they will "support the effort by answering questions from the porting effort." In terms of why they aren't doing a code drop like what happened with the Tegra K1 SoC where NVIDIA is publishing Nouveau patches, "The upstreaming work done on Tegra K1 is a separate effort; we have not announced a similar plan for desktop GPUs."
NVIDIA's sending out a GM107 Maxwell GPU to a Nouveau developer and answering their questions, thus there's no magic Nouveau Maxwell announcements that are imminent. When NVIDIA launched Kepler two years back, Nouveau got lucky and managed open-source Kepler support from nearly day one without the support of NVIDIA. Maxwell is a bigger upgrade than going from Fermi to Kepler so it may end up seeing some time before there's Nouveau Maxwell support -- users can start hoping for magic to see some basic mode-setting support in the Linux 3.15 kernel or the Mesa 10.2 release that's now three months out.
While it would have been nice to see more Maxwell open-source support, it's not a pity since as mentioned in the article there's bigger problems right now with Nouveau -- principally around power management / re-clocking. Until dynamic re-clocking is reliable and enabled "out of the box", the open-source NVIDIA Linux driver will continue running at piss poor speeds and not being power efficient... Maxwell is all about power efficiency and you can tap it's full potential today (sans overclocking) out of the NVIDIA 334 binary GPU driver. Of course, NVIDIA could always work on the re-clocking code or documentation for Nouveau, but they have already said that providing the PM information to the public would be among the most contentious areas to gain approval for releasing. It also took AMD several years before their Dynamic Power Management support became reliable in 2013 and enabled by default on the very latest Linux kernels.
More NVIDIA Linux benchmarks are on the way... Future Linux hardware test requests can be directed to Facebook, Twitter, and Google+.
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