1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Google Chrome OS Developers Working On DRM Code

Google

Published on 09 August 2013 10:45 AM EDT
Written by Michael Larabel in Google
Comment On This Article

There doesn't appear to be much to get excited about right now, but it appears some Google developers working on Chrome/Chromium OS have begun working on some improvements to the Linux DRM (Direct Rendering Manager) kernel graphics drivers.

Hitting the DRI-devel mailing list this week is code from Google's Sean Paul for introducing a "drm_bridge" component to the DRM kernel subsystem.
This patch adds the notion of a drm_bridge. A bridge is a chained device which hangs off an encoder. The drm driver using the bridge should provide the association between encoder and bridge. Once a bridge is associated with an encoder, it will participate in mode set, dpms, and optionally connection detection.

Since a connector may not be able to determine the connection state downstream of the bridge, bridges may implement detect() which will take precedence over connector detect() if the bridge is already attached to an encoder and that encoder is already attached to the connector. In practical terms, this requires the drm driver to make these associations at init time, which is fine for SoC applications where this link is static.

This Linux kernel patch adds some new interfaces but doesn't change any existing mainline DRM driver in the 200 line patch. In a follow-up message, Nouveau founder turned Googler St├ęphane Marchesin wrote, "We have two bridges using it here, and we're working on adding a third. [Rob Clark with the Freedreno/Qualcomm driver] want to add one too."

It will be interesting to see what the Google Chrome OS developers are working on next as it concerns Linux graphics. In the past they worked a lot on Intel Gallium3D support to use the "i915g" driver for older Chromebooks. Let's hope this current DRM work is part of a grander plan. When it comes to the current ARM-based Google devices they seem to use the Samsung Exynos SoC that already has a basic open-source DRM driver and for their growing Qualcomm devices there's open-source driver work being done independently through Freedreno.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. Trying The Configurable 45 Watt TDP With AMD's A10-7800 / A6-7400K
  2. Sumo's Omni Gets Reloaded
  3. AMD A10-7800 & A6-7400K APUs Run Great On Linux
  4. Radeon Gallium3D Is Running Increasingly Well Against AMD's Catalyst Driver
Latest Linux Articles
  1. Intel Sandy Bridge Gets A Surprise Boost From Linux 3.17
  2. Open-Source Radeon Graphics Have Some Improvements On Linux 3.17
  3. CPUFreq Scaling Tests With AMD's Kaveri On Linux 3.16
  4. Enabling HyperZ Is Still An Easy Way For Faster RadeonSI Performance
Latest Linux News
  1. DirectFB Updates GTK3 Support, Working Towards DirectFB 1.8
  2. Userptr Support Set For AMD Radeon GPUs In Linux 3.18
  3. NVIDIA Releases CUDA 6.5 As A Huge Update
  4. GNOME 3.14 Beta Makes GLSL Optional, Supports Wayland Gesture/Touch Events
  5. KDE Software Compilation 4.14 Released
  6. The Many Things You Can Build With A Raspberry Pi
  7. AMD's Catalyst Linux Driver Preparing For A World Without An X Server?
  8. Khronos Publishes Its Slides About OpenGL-Next
  9. Proposed: A Tainted Performance State For The Linux Kernel
  10. Systemd 216 Piles On More Features, Aims For New User-Space VT
Latest Forum Discussions
  1. AMD Offers Mantle For OpenGL-Next, Pushes Mantle To Workstations
  2. Systemd 216 Piles On More Features, Aims For New User-Space VT
  3. Dead Island for Linux (?)
  4. The dangers of Linux kernel development
  5. Remote gui not accessible in Phoronix Test Suite 5.2
  6. Updated and Optimized Ubuntu Free Graphics Drivers
  7. Next-Gen OpenGL To Be Announced Next Month
  8. OpenGL 4.5 Released With New Features