<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta name="generator" content= "HTML Tidy for Linux/x86 (vers 1 September 2005), see www.w3.org"> <meta http-equiv="Content-Type" content= "text/html; charset=us-ascii"> <title>Chapter 33. Direct Rendering Manager Kernel Modesetting (DRM KMS)</title> <meta name="generator" content="DocBook XSL Stylesheets V1.68.1"> <link rel="start" href="index.html" title= "NVIDIA Accelerated Linux Graphics Driver README and Installation Guide"> <link rel="up" href="installationandconfiguration.html" title= "Part I. Installation and Configuration Instructions"> <link rel="prev" href="randr14.html" title= "Chapter 32. Offloading Graphics Display with RandR 1.4"> <link rel="next" href="addressingcapabilities.html" title= "Chapter 34. Addressing Capabilities"> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">Chapter 33. Direct Rendering Manager Kernel Modesetting (DRM KMS)</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href= "randr14.html">Prev</a> </td> <th width="60%" align="center">Part I. Installation and Configuration Instructions</th> <td width="20%" align="right"> <a accesskey="n" href= "addressingcapabilities.html">Next</a></td> </tr> </table> <hr></div> <div class="chapter" lang="en"> <div class="titlepage"> <div> <div> <h2 class="title"><a name="kms" id= "kms"></a>Chapter 33. Direct Rendering Manager Kernel Modesetting (DRM KMS)</h2> </div> </div> </div> <div class="toc"> <p><b>Table of Contents</b></p> <dl> <dt><span class="section"><a href= "kms.html#drm-kms-known-issues">Known Issues</a></span></dt> </dl> </div> <p>The NVIDIA GPU driver package provides a kernel module, nvidia-drm.ko, which registers a DRM driver with the DRM subsystem of the Linux kernel. The capabilities advertised by this DRM driver depend on the Linux kernel version and configuration:</p> <div class="itemizedlist"> <ul type="disc"> <li> <p>PRIME: This is needed to support graphics display offload in RandR 1.4. Linux kernel version 3.13 or higher is required, with CONFIG_DRM enabled.</p> </li> <li> <p>Atomic Modeset: This is used for display of non-X11 based desktop environments, such as Wayland and Mir. Linux kernel version 4.1 or higher is required, with CONFIG_DRM and CONFIG_DRM_KMS_HELPER enabled.</p> </li> </ul> </div> <p>NVIDIA's DRM KMS support is still considered experimental. It is disabled by default, but can be enabled on suitable kernels with the 'modeset' kernel module parameter. E.g.,</p> <pre class="screen"> modprobe -r nvidia-drm ; modprobe nvidia-drm modeset=1 </pre> <p></p> <p>Applications can present through NVIDIA's DRM KMS implementation using any of the following:</p> <div class="itemizedlist"> <ul type="disc"> <li> <p>The DRM KMS "dumb buffer" mechanism to create and map CPU-accessible buffers: DRM_IOCTL_MODE_CREATE_DUMB, DRM_IOCTL_MODE_MAP_DUMB, and DRM_IOCTL_MODE_DESTROY_DUMB.</p> </li> <li> <p>Using the EGL_EXT_device_drm, EGL_EXT_output_drm, and EGL_EXT_stream_consumer_egloutput EGL extensions to associate EGLStream producers with specific DRM KMS planes.</p> </li> </ul> </div> <div class="section" lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a name= "drm-kms-known-issues" id="drm-kms-known-issues"></a>Known Issues</h2> </div> </div> </div> <div class="itemizedlist"> <ul type="disc"> <li> <p>The NVIDIA DRM KMS implementation is currently incompatible with SLI. The X server will fail to initialize SLI if DRM KMS is enabled.</p> </li> <li> <p>The NVIDIA DRM KMS implementation does not yet register an overlay plane: only primary and cursor planes are currently provided.</p> </li> <li> <p>Buffer allocation and submission to DRM KMS using gbm is not currently supported.</p> </li> </ul> </div> </div> </div> <div class="navfooter"> <hr> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href= "randr14.html">Prev</a> </td> <td width="20%" align="center"><a accesskey="u" href= "installationandconfiguration.html">Up</a></td> <td width="40%" align="right"> <a accesskey="n" href= "addressingcapabilities.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top"> Chapter 32. Offloading Graphics Display with RandR 1.4 </td> <td width="20%" align="center"><a accesskey="h" href= "index.html">Home</a></td> <td width="40%" align="right" valign="top"> Chapter 34. Addressing Capabilities</td> </tr> </table> </div> </body> </html>