Eugeni's blog

Yeah, I admit that my semi-periodic updates about Intel Linux Graphics got more “seldom-periodic” than “truly-periodic” for the past weeks. But have no fear – they are back! And I am still on my self-appointed bi-weekly schedule estimate. This is what’s good about semi-periodic schedule – one never can run too much out of it .

So starting with the coolest news – the Mesa team is getting close to the GL 3.0 milestone! Yeah, with latest GL_ext_transform_feedback patches from Paul Berry, the last major piece of GL 3.0 spec is getting into place. There are still some extensions missing and lots of smaller tasks to be done, but it is possible to say that we are almost there. I think that this is really exciting for both us, and for all the Linux and open-source users in the world – so yeah – we’ve been good boys and girls during the year and Santa Claus gift has materialized itself in form of almost-full GL 3.0 support in Mesa.

Who knows, maybe prior to the Chinese new year we’ll receive the 2nd part of this gift (in other words, mesa 8.0 release ).

On kernel side, the 3.2-rc6 release brought lots of awesome changes to our drivers. Yes, I am talking about everyone’s favorite rc6 and semaphores features. They are on by default on Ivy Bridge architecture, and are also enabled on Sandy Bridge if VTd is disabled. So most of you should enjoy greatly improved battery life, considerable faster performance and also enhanced stability within the i915 driver when Linux 3.2 will be released.

Besides those patches, work has started on collecting patches for the 3.3 merge window. Daniel Vetter sent his pending patches in a form of tiny 43-patches series. Those patches bring PPGTT support, improve debugfs handling, enhance pread/pwrite performance, fix swizzling for SNB/IVB, improve forcewake operations and enhance debugging support for cases when GPU rings get stuck.

Ben has also sent his patches for scheduling/throttling, but they haven’t received much interest except from myself and phoronix . Those patches add support for more fine-grained GPU scheduling and rings load distribution between individual process. I am really interested in this work, and I hope that they will be accepted into the main kernel in the foreseeable future.

Also on kernel, Rodrigo Vivi and Paulo Zanoni sent out some patches which finally fix some corner cases for TV-out and SDVO outputs. This certainly should make many users happy out there just in time for Christmas.

And finally, for the kernel size, Chris Wilson came with a patch which works around the missed IRQs issues on Ivy Bridge platform. With this patch, and with semaphores being enabled on Ivy Bridge by default, I am very happy to say that we don’t have any blocking bugs for Ivy Bridge in our bugzilla. I think that it comes as a nice Christmas gift for all the users out there (the ones who already have an Ivy Bridge machine, and the ones who will get it by its launch – which is still 4 months away). Of course, I won’t talk much about it prior to its official launch, but trust me – Ivy Bridge rocks!. I can’t wait to have an Ultrabook based on this platform for myself…

Besides mesa and kernel, it is worth mentioning that on the 2D side, Zhigang added full Glamor support into the driver. The Glamor acceleration is still considered very experimental and non-stable, but now it is available for the world to take a peek on it and witness how it works with their own eyes.

So I think that this is pretty much it. We have hundreds of patches floating around for all the projects, thousands of emails and millions of users in the world – and we are working hard to make all of them happy with the results of our work. 2011 was extremely productive and rewarding for us – and I hope that the year of 11111011100 (a.k.a., 0x7DC or 2012_base10 for the ones still reading in decimal numbers out there ) will be even more interesting*!

See you!

(*) Assuming the world won’t end in a core dump caused by the Mayan millennium counter overflow bug .

Development goes on, on all the fronts, and time has come for some news about Intel Linux Graphics project.

For the Kernel side, some nice patch series have arrived to the list:

• Daniel Vetter sent his PPGTT enabling patches, which resulted in many interesting reviews and discussions. PPGTT, or Per-Process Graphics Translation Table, is a mechanism for remapping GPU memory into system one. Unlike traditional Graphics Translation Table, which has a global mapping for everything, PPGTT allows each process to have its own level of mapping. On practice, it should improve stability by a large margin and performance by a considerable value, and also is a nice thing to have in general, specially when hardware supports it natively (which it does, starting with Sandy Bridge). Also, if you are interested in learning the details of how GTT and GPU memory management works, you should check this excellent article from 2007 for a great introduction.
• Ben Widawsky has sent a new series of patches for forced GPU throttling and scheduling. I already described them in one of the previous posts, and I am really interested in seeing them accepted to the kernel.
• I’ve sent out some patches for userspace-controled RC6 enabling and tweaking, together with some patches for enabling semaphores and rc6 by default on newer generations of gfx hardware. Those patches, together with Ben’s ones, also raised an interesting point – we have many userspace-controllable items in the debugfs file system, which should probably belong to sysfs instead. This would require a proper definition of their usage and behavior before real userspace applications would be able to use them.
• And Wu Fengguang sent some patches for Display Port and HDMI fixes.

Moving up the stack to the 3D driver, some major news worth highlighting are:

• On Mesa side, the major news is Ian has released Mesa 7.11.2 with some additional GLES and EGL patches, and a small patch which fixed Mesa build on Mandriva (and also on other distributions which use -Werror by default, such as Mageia for example).
• Lots of work is happening in Mesa, targeting OpenGL 3.0 support by the end of the year. GLSL 1.30 is already among us, and most of GL 3.0-required extensions are in place, but there are many things to do. Hopefully they will be all done in the next few weeks.
• Speaking on Mesa, some major news happened for the drivers using the Gallium technology. As you probably heard through Phoronix already, the i965g, Cell and Failover gallium-based drivers were dropped from Mesa due to lack of love, support and care. Sad – but this is life. And in any case, i915g driver is still there, and of course, those events do not affect Intel’s 915 and 965 Mesa drivers at all.
• And also on Mesa, Ian has started the work on GLX_ARB_create_context and the layered GLX_ARB_create_context_profile extension, and came with a question whether it is still worthy to support non-XCB protocol, or if there are any platforms that can’t / don’t use XCB for X protocol yet. The overall feedback so far was to drop non-XCB bits sooner than later. So looks like XCB has won the X protocol war in the end .

And finally, on the xserver side, discussions were raised on the mailing list on the release dates for the next xserver release, and the Xinput 2.2 state in it. It is almost there, and will probably get merged until Christmas. Also, Xorg-server 1.11.2.901 (a.k.a., 1.11.3-RC2) was released.