|  | ************************************************************ | 
|  | * For the very latest on DRI development, please see:      * | 
|  | *     http://dri.freedesktop.org/                          * | 
|  | ************************************************************ | 
|  |  | 
|  | The Direct Rendering Manager (drm) is a device-independent kernel-level | 
|  | device driver that provides support for the XFree86 Direct Rendering | 
|  | Infrastructure (DRI). | 
|  |  | 
|  | The DRM supports the Direct Rendering Infrastructure (DRI) in four major | 
|  | ways: | 
|  |  | 
|  | 1. The DRM provides synchronized access to the graphics hardware via | 
|  | the use of an optimized two-tiered lock. | 
|  |  | 
|  | 2. The DRM enforces the DRI security policy for access to the graphics | 
|  | hardware by only allowing authenticated X11 clients access to | 
|  | restricted regions of memory. | 
|  |  | 
|  | 3. The DRM provides a generic DMA engine, complete with multiple | 
|  | queues and the ability to detect the need for an OpenGL context | 
|  | switch. | 
|  |  | 
|  | 4. The DRM is extensible via the use of small device-specific modules | 
|  | that rely extensively on the API exported by the DRM module. | 
|  |  | 
|  |  | 
|  | Documentation on the DRI is available from: | 
|  | http://dri.freedesktop.org/wiki/Documentation | 
|  | http://sourceforge.net/project/showfiles.php?group_id=387 | 
|  | http://dri.sourceforge.net/doc/ | 
|  |  | 
|  | For specific information about kernel-level support, see: | 
|  |  | 
|  | The Direct Rendering Manager, Kernel Support for the Direct Rendering | 
|  | Infrastructure | 
|  | http://dri.sourceforge.net/doc/drm_low_level.html | 
|  |  | 
|  | Hardware Locking for the Direct Rendering Infrastructure | 
|  | http://dri.sourceforge.net/doc/hardware_locking_low_level.html | 
|  |  | 
|  | A Security Analysis of the Direct Rendering Infrastructure | 
|  | http://dri.sourceforge.net/doc/security_low_level.html |