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

Intel Pulls In ShadowFB Support For KMS

Intel

Published on 08 September 2010 10:28 AM EDT
Written by Michael Larabel in Intel
11 Comments

While Ubuntu 10.10 will have no i8xx driver fix for those with this vintage Intel hardware that's been plagued with stability problems and other issues since Intel introduced their Linux kernel mode-setting and GEM driver, there is now a workaround upstream for this issue. Originally the plan was to add back user-space mode-setting support to the Intel X.Org driver that would not use the Graphics Execution Manager (GEM) and this code-path could be enabled by i8xx customers to workaround the cache coherency issues while losing KMS support, but a new workaround was devised.

Adding back UMS support to the xf86-video-intel driver would add around 50,000 lines of code back to the DDX driver and it would likely receive little in the way of new development and testing, so a much less invasive solution was devised by Intel's Chris Wilson. This new workaround, which we talked about recently, was adding shadow frame-buffer support to Intel KMS. In other words, kernel mode-setting still could be used by i8xx owners, but a ShadowFB-like method would be used for acceleration, which basically means no GPU acceleration at all.

The few hundred line commit adding shadow frame-buffer support to the Intel driver was merged to master early this morning. When the Shadow option is enabled from the xorg.conf, no GPU acceleration will be used but rather it will be leveraged on the CPU and system memory. No X-Video or 3D acceleration can be used with this driver, but now at least there is X-Video still possible via the hardware overlay. But because GEM isn't being tapped, the incoherency bugs for i8xx should be worked around thereby giving you a stable system.

The commit showing this shadow support being merged into the mainline xf86-video-intel driver can be found on Git. This support will be found in the xf86-video-intel 2.13 driver, which should be released in a few weeks.

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. A Walkthrough Of The New 32 System Open-Source Linux Benchmarking Test Farm
  2. Habey MITX-6771: Mini-ITX Board With Quad-Core J1900 Bay Trail
  3. OCZ Vector 150 SSD On Linux
  4. Noctua i4 CPU Cooler: Great For Cooling High-End LGA-2011v3 CPUs
Latest Linux Articles
  1. AMD Kaveri: Open-Source Radeon Gallium3D vs. Catalyst 14.12 Omega Driver
  2. 12-Way AMD Catalyst 14.12 vs. NVIDIA 346 Series Linux GPU Comparison
  3. AMD Catalyst 14.12 Omega Driver Brings Mixed Results For Linux Users
  4. 6-Way Winter 2014 Linux Distribution Comparison
Latest Linux News
  1. Linux 3.19-rc1 Kernel Released Ahead Of Schedule
  2. Civilization: Beyond Earth Linux GPU/Driver Benchmarks
  3. X.Org Server 1.16.3 Released To Fix Security Issues
  4. Linux 3.19 Merge Window Closes Ahead Of Schedule
  5. MIPS R6 Architecture Now Supported By GCC
  6. LowRISC To Feature Tagged Memory & Minion Cores
  7. Intel Skylake Audio Support For Linux 3.19
  8. After 10+ Years, NetworkManager Reaches v1.0
  9. VDPAU Updated To v0.9
  10. An Open Hardware Random Number Generator Proposed
Latest Forum Discussions
  1. FPS capped on Linux (AMD fglrx drivers)
  2. Need some hand holding with upgrading xserver
  3. Are there an app using HSA ?
  4. The New SuperTuxKart Looks Better, But Can Cause GPU/Driver Problems
  5. XLennart: A Game For Systemd Haters With Nothing Better To Do
  6. Updated and Optimized Ubuntu Free Graphics Drivers
  7. Debian init discussion in Phoenix Wright format
  8. Bench specific mount point