Oops. They did it again.
It hit the market during the last few weeks. Last generation of Intel Atoms: CedarView (D2300, D2500, D2550, D2600, D2700) and Cedar Trail (N2600, N2700, N2800) SoCs integrate a PowerVR GPU from Imagination instead of the usual Intel GPU. If you remember the Poulsbo fiasco, it's the same. More or less.
An unsupported graphic card on Linux distributions, and which can't properly support a basic desktop environnment like Unity or Gnome 3.
To prevent this issue, Intel woke up MeeGo from the dead in last february [to add support for CedarView]((http://www.phoronix.com/scan.php?page=news_item&px=MTA1ODI). And to publish the proprietary Linux driver, in a fairly exotic fashion. This driver is only available in MeeGo repositories. Upstream First? It doesn't seem to be a priority.
Note that this proprietary driver requires adding a 100k+ line patch to the kernel. Available only in the MeeGo source rpm, of course.
Alan Cox, one of the top Linux kernel developers, has been working on modesetting driver for the GMA500 family: he single-handedly added support to turn on the screen and to set it to the right resolution, without an X server. This driver even went out of the kernel staging area recently.
There's also a new Xorg driver: modesetting. This driver is written specifically for the new range of GPUs with kernel modesetting support. But without hardware acceleration.
If you spend your day in a terminal with a tiling window manager, this might not be a big deal for you. Otherwise, you'll miss on quite a few things:
- Compositing, allowing snappy and smooth window management; it's mandatory with Unity and Gnome Shell.
- WebGL, allowing a whole new class of webapps and implemented in all modern browsers.
- Basic video acceleration: wan't to play 1080p videos ? forget it. Want to use Skype ? Not without Xv.
- want to enjoy great indie games ? Not possible.
My personnal advice is to look at AMD's offering: the Fusion line up is starting to be very well supported in the upstream open source stack(kernel/libdrm/ddx/mesa), as long it's up-to-date.
Next gen Atom (ValleyView) should have a "classic" Intel GPU from IvyBridge. But they won't be widely available before 2013, so until then, you should be careful.
Intel's Mobile push (with Medfield) will only conceal the issue. Indeed, Intel needs smartphone-capable SoCs, and that means dealing with Imagination. The Lava Xolo X900, or Orange San Diego, already has a PowerVR GPU, like a lot of competing smartphones. It was not by mistake that the FSF made a free PowerVR driver a high priority project. Maybe the Lima or freedreno project will help change things backstage, in the ivory tower of SoC IPs design. It's hard to make predictions.
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I've played around with these Cedarview chips quite a bit - there are packages available for Ubuntu 12.04 which will work on other glibc 2.15 systems, and with these drivers the setup works pretty admirably. Hardware video decoding works, HDMI output works, and you can watch 1080p video with the CPU idling. It's not as terrible as you make it out to be.
I believe that the problem with open source support for this graphics hardware is that it's used in so many high volume, high markup proprietary devices - to wit, the iPhone, the iPad, the new Sony portable gaming unit whose name escapes me, and a huge variety of phones. IMGTEC only sells IP, they don't manufacture the hardware, so it's not like AMD/Nvidia/Intel where you have reference designs - there's enormous fragmentation among the SGX 5 based chipsets on the market today, and all of the big players have no interest in seeing open source as a first class citizen.
To make matters worse, the design of these chips is wildly different than most other available graphics chipsets. To put it simply: I don't believe anyone is going to reverse engineer a workable driver in the useful lifetime of the SGX 5.