Linux 3.12 Enables Haswell's Iris eLLC Cache Support
Written by Michael Larabel in Intel on 2 September 2013 at 10:53 AM EDT. 5 Comments
The Intel Haswell processors with Iris Pro 5200 "GT3e" graphics sports 128MB of embedded DRAM for maximizing the Intel graphics performance. With the Linux 3.12 kernel, this "eLLC cache" is being enabled in full plus other Intel DRM driver changes for benefiting Intel Linux customers.

Unfortunately we still don't have any Iris Pro 5200 benchmarks on Phoronix due to simply not yet having any GT3e hardware, but Daniel Vetter has written on his blog about the Linux 3.12 i915 DRM changes and with that he notes the GT3e hardware has the eLLC cache enabled.

Ben Widawsky enabled the giant eLLC cache while Chris Wilson enabled a write-through scanout buffer-caching mode that benefits hardware with this embedded DRAM package.

Other Intel graphics changes for the Linux 3.12 kernel include enabling PC8+ support as a deeper system sleep state for Haswell ULT platforms, Panel Self Refresh (PSR) support is now in place as another Haswell power-saving feature, and an assortment of other improvements.

Some of the smaller work includes GPU error state reporting via sysfs, HDMI infoframe changes, Fastboot support, and VMA object support for GEM.

More information on the Intel DRM driver changes queued up for merging into the Linux 3.12 kernel as soon as Linux 3.11 has been released can be found on Daniel's blog. You can also read about other great features for the Linux 3.12 kernel on top of the Linux 3.11 features.

About The Author
Author picture

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via Twitter or contacted via

Related Intel News
Popular News
Trending Reviews & Featured Articles