1257 lines
46 KiB
Plaintext
1257 lines
46 KiB
Plaintext
DRI User Guide
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VA Linux Systems, Inc. Professional Services - Graphics.
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15 June 2001
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1. Preamble
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1.1 Copyright
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Copyright 2000-2001 by VA Linux Systems, Inc. All Rights Reserved.
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Permission is granted to make and distribute verbatim copies of this document
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provided the copyright notice and this permission notice are preserved on all
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copies.
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1.2 Trademarks
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OpenGL is a registered trademark and SGI is a trademark of Silicon Graphics,
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Inc. Unix is a registered trademark of The Open Group. The `X' device and X
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Window System are trademarks of The Open Group. XFree86 is a trademark of
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The XFree86 Project. Linux is a registered trademark of Linus Torvalds.
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Intel is a registered trademark of Intel Corporation. 3Dlabs, GLINT, and
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Oxygen are either registered trademarks or trademarks of 3Dlabs Inc. Ltd.
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3dfx, Voodoo3, Voodoo4, and Voodoo5 are registered trademarks of 3dfx Inter-
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active, Incorporated. Matrox is a registered trademark of Matrox Electronic
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Systems Ltd. ATI Rage and Radeon are registered trademarks of ATI Technolo-
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gies, Inc. All other trademarks mentioned are the property of their respec-
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tive owners.
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2. Introduction
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With XFree86 4.x and the Direct Rendering Interface (DRI), hardware acceler-
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ated 3D graphics can be considered a standard feature on Linux workstations.
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Support for other operating systems, such as FreeBSD, is underway.
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This document describes how to use the DRI system and troubleshoot problems
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which may occur. Readers should have a basic understanding of Linux, X and
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OpenGL. See the resources section at the end for more documentation and
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software downloads.
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This document does not cover compilation or installation of XFree86 4.x. It
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is assumed that you've already installed a Linux distribution which includes
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XFree86 4.x or that you're an experienced Linux developer who has compiled
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the DRI for himself. DRI download, compilation and installation instructions
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can be found at http://dri.sourceforge.net/DRIcompile.html
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Edits, corrections and updates to this document may be mailed to <brian@tung-
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stengrahpics.com>.
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3. Supported Architectures & Hardware
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3.1 CPU Architectures
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The architectures currently supported by the DRI have grown from the initial
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Intel i386 systems to now include the Alpha Processor and the Sun SPARC
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machines.
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Intel's SSE (a.k.a. Katmai) instructions are used in optimized vertex trans-
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formation functions in Mesa-based drivers. This requires a recent Linux ker-
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nel both at compile and runtime. See the DRI Compile Guide for compile-time
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requirements. At runtime a check is made to determine if the CPU can execute
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SSE instructions. They're disabled otherwise.
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AMD's 3DNow! instructions are also used in optimized vertex transformation
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functions in the Mesa-based DRI drivers. 3DNow! is supported in most ver-
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sions of Linux. Like the SSE optimizations, a runtime check is made to
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determine if the CPU can execute 3DNow! instructions.
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Alpha-based systems can use Compaq's optimized math library for improved 3D
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performance. See the DRI Compilation Guide for details.
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3.2 Graphics Hardware
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XFree86 4.2 (or later versions) includes 3D acceleration for the following
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graphics hardware:
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o 3dfx, supported on Intel x86, AMD and Alpha:
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o Voodoo5 5500
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o Voodoo4 4500
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o Voodoo3 3500 TV
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o Voodoo3 3000 AGP
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o Voodoo3 3000 PCI
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o Voodoo3 2000 AGP
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o Voodoo3 2000 PCI
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o Voodoo Banshee
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o Velocity 100/200
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There are many configurations of 3dfx cards on the market. Not all have
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been tested.
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o Matrox, supported on Intel x86 and AMD:
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o Matrox G200
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o Matrox G400
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o Intel i810/i815/i830 (motherboard chipsets)
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o i810
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o i810-dc100
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o i810e
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o i815
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o i830
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o ATI Rage 128, supported on Intel x86, AMD and Alpha:
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o Rage Fury
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o Rage Magnum
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o XPERT 2000
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o XPERT 128
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o XPERT 99
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o All-in-Wonder 128
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o Rage 128 PCI (Alpha-based systems)
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Note that both PCI and AGP versions of Rage 128 based cards are sup-
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ported at this time.
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o ATI Radeon, supported on Intel x86, AMD and Alpha:
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o Radeon SDR AGP
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o Radeon DDR AGP
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o Radeon 32MB SDR PCI (Alpha-based systems)
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o Radeon 7000, M6 (RV100)
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o Radeon 7200 (R100)
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o Radeon 7500, M7 (RV200)
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o Radeon 8500, 9100 (R200)
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o Radeon 9000, M9 (RV250)
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o 3Dlabs, supported on Intel x86 and AMD:
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o Oxygen GMX 2000 (MX/Gamma based). Note: this driver is no longer
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being actively developed.
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Support for other hardware is underway. Most of the DRI development work is
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funded by contracts with IHVs. These contracts often prevent us from
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announcing drivers before they're released. Queries about upcoming drivers
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may not be answerable.
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4. Prerequisite Software
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o The DRI is available in XFree86 4.0 and later.
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o Some hardware drivers require specific versions of the Linux kernel for
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AGP support, etc. See section 10 for specifics.
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o You DO NOT need to install Mesa separately. The parts of Mesa needed
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for hardware acceleration are already in the XFree86/DRI project.
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5. Kernel Modules
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3D hardware acceleration requires a DRI kernel module that's specific to your
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graphics hardware.
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The DRI kernel module version must exactly match your running kernel version.
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Since there are so many versions of the kernel, it's difficult to provide
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precompiled kernel modules.
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While the Linux source tree includes the DRI kernel module sources, the lat-
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est DRI kernel sources will be found in the DRI source tree.
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See the DRI Compilation Guide for information on compiling the DRI kernel
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modules.
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XFree86 4.0.1 added automatic kernel module loading to the X server. On
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Linux, the X server uses modprobe to load kernel modules. In Linux 2.4.x the
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DRM kernel modules should be kept in /lib/modules/2.4.x/ker-
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nel/drivers/char/drm/ for automatic loading to work.
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Optionally, DRM kernel modules can be loaded manually with insmod prior to
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starting the X server.
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You can verify that the kernel module was installed with lsmod, checking the
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X server startup log, and checking that /proc/dri/0 exists.
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6. XF86Config file
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The XFree86 configuration file is usually found in /etc/X11/XF86Config. This
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section describes the parts which must be specially set for the DRI.
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First, the XF86Config file must load the GLX and DRI modules:
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Section "Module"
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...
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# This loads the GLX module
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Load "glx"
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# This loads the DRI module
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Load "dri"
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EndSection
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Next, the DRI section can be used to restrict access to direct rendering. A
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client can only use direct rendering if it has permission to open the
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/dev/dri/card? file(s). The permissions on these DRI device files is con-
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trolled by the "DRI" section in the XF86Config file.
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If you want all of the users on your system to be able to use direct-render-
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ing, then use a simple DRI section like this:
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Section "DRI"
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Mode 0666
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EndSection
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This section will allow any user with a current connection to the X server to
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use direct rendering.
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If you want to restrict the use of direct-rendering to a certain group of
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users, then create a group for those users by editing the /etc/group file on
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your system. For example, you may want to create a group called xf86dri and
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place two users (e.g., fred and jane) in that group. To do that, you might
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add the following line to /etc/group:
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xf86dri:x:8000:fred,jane
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You have to be careful that the group id (8000 in this example) is unique.
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Then you would use the following DRI section:
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Section "DRI"
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Group "xf86dri"
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Mode 0660
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EndSection
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This would limit access to direct-rendering to those users in the xf86dri
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group (fred and jane in this example). When other users tried to use direct
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rendering, they would fall back to unaccelerated indirect rendering.
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[Note that there is a known bug in XFree86 4.0 that prevents some changes to
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the DRI section from taking effect. Until this bug is fixed, if you change
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the DRI section, please also remove the /dev/dri directory with the rm -rf
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/dev/dri command.]
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Finally, the XF86Config file needs Device and Screen sections specific to
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your hardware. Look in section 10: Hardware-Specific Information and Trou-
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bleshooting for details.
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7. Memory usage
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Using the 3D features of a graphics card requires more memory than when it's
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just used as a 2D device. Double buffering, depth buffering, stencil
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buffers, textures, etc. all require extra graphics memory. These features
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may require four times the memory used for a simple 2D display.
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If your graphics card doesn't have a lot of memory (less than 16MB, for exam-
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ple), you may have to reduce your screen size and/or color depth in order to
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use 3D features. Reducing the screen resolution will also leave more space
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for texture images, possibly improving 3D performance. If, for example, you
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play Quake3 at 1024x768 but start your display at 1600x1200 you might con-
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sider restarting X at 1024x768 in order to maximize your texture memory
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space.
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The documentation included with your card should have information about maxi-
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mum screen size when using 3D.
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8. Using 3D Acceleration
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This section describes how to link your application with libGL.so and verify
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that you are in fact using 3D acceleration.
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8.1 libGL.so
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Your OpenGL program must link with the libGL.so.1.2 library provided by
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XFree86. The libGL.so.1.2 library contains a GLX protocol encoder for indi-
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rect/remote rendering and DRI code for accessing hardware drivers. In par-
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ticular, be sure you're not using libGL.so from another source such as Mesa
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or the Utah GLX project.
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Unless it was built in a special way, the libGL.so library does not contain
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any 3D hardware driver code. Instead, libGL.so dynamically loads the appro-
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priate 3D driver during initialization.
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Most simple OpenGL programs also use the GLUT and GLU libraries. A source
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for these libraries is listed in the Resources section below.
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8.2 Compiling and linking an OpenGL program
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A simple GLUT/OpenGL program may be compiled and linked as follows:
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gcc program.c -I/usr/local/include -L/usr/local/lib -L/usr/X11R6/lib -lglut -lGLU -lGL -o program
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The -I option is used to specify where the GL/glut.h (and possibly the
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GL/gl.h and GL/glu.h) header file may be found.
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The -L options specify where the libglut.so and the X libraries are located.
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libGL.so and libGLU.so should be in /usr/lib, as specified by the
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Linux/OpenGL ABI standard.
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The -lglut -lGLU -lGL arguments specify that the application should link with
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the GLUT, GLU and GL libraries, in that order.
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8.3 Running your OpenGL program
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Simply typing ./program in your shell should execute the program.
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If you get an error message such as
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gears: error in loading shared libraries: libGL.so.1: cannot
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open shared object file: No such file or directory
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if means that the libGL.so.1 file is not the right location. Proceed to the
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trouble shooting section.
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8.4 libOSMesa.so
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OSMesa (Off-Screen Mesa) is an interface and driver for rendering 3D images
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into a user-allocated block of memory rather than an on-screen window. It
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was originally developed for Mesa before Mesa became part of the XFree86/DRI
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project. It can now be used with the XFree86/DRI libGL.so as well.
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libOSMesa.so implements the OSMesa interface and it must be linked with your
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application if you want to use the OSMesa functions. You must also link with
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libGL.so. For example:
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gcc osdemo.c -lOSMesa -lGLU -lGL -o osdemo
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In stand-alone Mesa this interface was compiled into the monolithic libGL.so
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(formerly libMesaGL.so) library. In XFree86 4.0.1 and later this interface
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is implemented in a separate library.
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8.5 glxinfo
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glxinfo is a useful program for checking which version of libGL you're using
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as well as which DRI-based driver. Simply type glxinfo and examine the
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OpenGL vendor, renderer, and version lines. Among the output you should see
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something like this:
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OpenGL vendor string: VA Linux Systems, Inc.
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OpenGL renderer string: Mesa DRI Voodoo3 20000224
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OpenGL version string: 1.2 Mesa 3.4
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or this:
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OpenGL vendor string: VA Linux Systems, Inc.
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OpenGL renderer string: Mesa GLX Indirect
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OpenGL version string: 1.2 Mesa 3.4
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The first example indicates that the 3dfx driver is using Voodoo3 hardware.
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The second example indicates that no hardware driver was found and indirect,
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unaccelerated rendering is being used.
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If you see that indirect rendering is being used when direct rendering was
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expected, proceed to the troubleshooting section.
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glxinfo also lists all of the GLX-enhanced visuals available so you can
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determine which visuals are double-bufferd, have depth (Z) buffers, stencil
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buffers, accumulation buffers, etc.
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8.6 Environment Variables
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The libGL.so library recognizes three environment variables. Normally, none
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of them need to be defined. If you're using the csh or tcsh shells, type
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setenv VARNAME value to set the variable. Otherwise, if you're using sh or
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bash, type export VARNAME=value.
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1. LIBGL_DEBUG, if defined will cause libGL.so to print error and diagnos-
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tic messages. This can help to solve problems. Setting LIBGL_DEBUG to
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verbose may provide additional information.
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2. LIBGL_ALWAYS_INDIRECT, if defined this will force libGL.so to always
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use indirect rendering instead of hardware acceleration. This can be
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useful to isolate rendering errors.
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3. LIBGL_DRIVERS_PATH can be used to override the default directories
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which are searched for 3D drivers. The value is one or more paths sep-
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arated by colons. In a typical XFree86 installation, the 3D drivers
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should be in /usr/X11R6/lib/modules/dri/ and LIBGL_DRIVERS_PATH need
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not be defined. Note that this feature is disabled for set-uid pro-
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grams. This variable replaces the LIBGL_DRIVERS_DIR env var used in
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XFree86 4.0.
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4. MESA_DEBUG, if defined, will cause Mesa-based 3D drivers to print user
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error messages to stderr. These are errors that you'd otherwise detect
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by calling glGetError.
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Mesa-based drivers (this includes most of the drivers listed above) also
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observe many of the existing Mesa environment variables. These include the
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MESA_DEBUG and MESA_INFO variables.
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9. General Trouble Shooting
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This section contains information to help you diagnose general problems. See
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below for additional information for specific hardware.
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9.1 Bus Mastering
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DMA-based DRI drivers (that's most DRI drivers) cannot function unless bus
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mastering is enabled for your graphics card. By default, some systems don't
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having bus mastering on. You should enable it in your BIOS.
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Alternately, you can check the status of bus mastering and change the setting
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from within Linux. There may be similar procedures for other operating sys-
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tems.
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Run lspci (as root) and find the information describing your graphics
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adapter. For example:
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00:00.0 Host bridge: Intel Corporation 440BX/ZX - 82443BX/ZX Host bridge (rev 03)
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00:01.0 PCI bridge: Intel Corporation 440BX/ZX - 82443BX/ZX AGP bridge (rev 03)
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00:07.0 ISA bridge: Intel Corporation 82371AB PIIX4 ISA (rev 02)
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00:07.1 IDE interface: Intel Corporation 82371AB PIIX4 IDE (rev 01)
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00:07.2 USB Controller: Intel Corporation 82371AB PIIX4 USB (rev 01)
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00:07.3 Bridge: Intel Corporation 82371AB PIIX4 ACPI (rev 02)
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00:11.0 Ethernet controller: Intel Corporation 82557 [Ethernet Pro 100] (rev 08)
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00:12.0 SCSI storage controller: Symbios Logic Inc. (formerly NCR) 53c895 (rev 02)
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00:14.0 Multimedia audio controller: Ensoniq ES1371 [AudioPCI-97] (rev 08)
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01:00.0 VGA compatible controller: 3Dfx Interactive, Inc.: Unknown device 0009 (rev 01)
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The bus, device, and function number comprise the device id, which is conven-
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tionally written in the form bus:dev.func, or in this case 01:00.0.
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Use the setpci command to examine bit two of register 4 for your graphics
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card. This will indicate whether or not bus mastering is enabled.
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setpci -s 01:00.0 4.w
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A hexadecimal value will be printed. Convert the least significant digit to
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binary. For example, if you see 3, that's 0011 in binary (bit two is 0). If
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you see 7, that's 0111 in binary (bit two is 1). In the first example, bus
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mastering is disabled. It's enabled in the second example.
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The following shell script will enabled bus mastering for your graphics card
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and host bridge. Run it as root.
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#!/bin/bash
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dev=01:00.0 # change as appropriate
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echo Enabling bus mastering on device $dev
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setpci -s $dev 4.w=$(printf %x $((0x$(setpci -s $dev 4.w)|4)))
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dev=00:00.0
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echo Enabling bus mastering on host bridge $dev
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setpci -s $dev 4.w=$(printf %x $((0x$(setpci -s $dev 4.w)|4)))
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You can check if this worked by running the first setpci command again.
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9.2 The X Server
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1. Before you start the X server, verify the appropriate 3D kernel module
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is installed. Type lsmod and look for the appropriate kernel module.
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For 3dfx hardware you should see tdfx, for example.
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2. Verify you're running XFree86 4.0 (or newer) and not an older version.
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If you run xdpyinfo and look for the following line near the top:
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vendor release number: 4000
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3. Verify that your XF86Config file (usually found at /etc/X11/XF86Config)
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loads the glx and dri modules and has a DRI section.
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See the Software Resources section below for sample XF86Config files.
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4. Examine the messages printed during X server startup and check that the
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DRM module loaded. Using the Voodoo3 as an example:
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(==) TDFX(0): Write-combining range (0xf0000000,0x2000000)
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(II) TDFX(0): Textures Memory 7.93 MB
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(0): [drm] created "tdfx" driver at busid "PCI:1:0:0"
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(0): [drm] added 4096 byte SAREA at 0xc65dd000
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(0): [drm] mapped SAREA 0xc65dd000 to 0x40013000
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(0): [drm] framebuffer handle = 0xf0000000
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(0): [drm] added 1 reserved context for kernel
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(II) TDFX(0): [drm] Registers = 0xfc000000
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(II) TDFX(0): visual configs initialized
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(II) TDFX(0): Using XFree86 Acceleration Architecture (XAA)
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Screen to screen bit blits
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Solid filled rectangles
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8x8 mono pattern filled rectangles
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Indirect CPU to Screen color expansion
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Solid Lines
|
|
Dashed Lines
|
|
Offscreen Pixmaps
|
|
Driver provided NonTEGlyphRenderer replacement
|
|
Setting up tile and stipple cache:
|
|
10 128x128 slots
|
|
(==) TDFX(0): Backing store disabled
|
|
(==) TDFX(0): Silken mouse enabled
|
|
(0): X context handle = 0x00000001
|
|
(0): [drm] installed DRM signal handler
|
|
(0): [DRI] installation complete
|
|
(II) TDFX(0): direct rendering enabled
|
|
|
|
5. After the X server has started, verify that the required X server
|
|
extensions are loaded. Run xdpyinfo and look for the following entries
|
|
in the extensions list:
|
|
|
|
GLX
|
|
SGI-GLX
|
|
XFree86-DRI
|
|
|
|
9.3 Linking, running and verifying 3D acceleration
|
|
|
|
After you've verified that the X server and DRI have started correctly it's
|
|
time to verify that the GL library and hardware drivers are working cor-
|
|
rectly.
|
|
|
|
1. Verify that you're using the correct libGL.so library with ldd. The
|
|
/usr/lib and /usr/X11R6/lib directories are expected locations for
|
|
libGL.so.
|
|
|
|
Example:
|
|
|
|
% ldd /usr/local/bin/glxinfo
|
|
libglut.so.3 => /usr/local/lib/libglut.so.3 (0x40019000)
|
|
libGLU.so.1 => /usr/local/lib/libGLU.so.1 (0x40051000)
|
|
libGL.so.1 => /usr/lib/libGL.so.1 (0x40076000)
|
|
libXmu.so.6 => /usr/X11R6/lib/libXmu.so.6 (0x402ee000)
|
|
libXi.so.6 => /usr/X11R6/lib/libXi.so.6 (0x40301000)
|
|
libm.so.6 => /lib/libm.so.6 (0x40309000)
|
|
libc.so.6 => /lib/libc.so.6 (0x40325000)
|
|
libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x40419000)
|
|
libXt.so.6 => /usr/X11R6/lib/libXt.so.6 (0x404bd000)
|
|
libSM.so.6 => /usr/X11R6/lib/libSM.so.6 (0x40509000)
|
|
libICE.so.6 => /usr/X11R6/lib/libICE.so.6 (0x40512000)
|
|
libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x40529000)
|
|
libvga.so.1 => /usr/lib/libvga.so.1 (0x40537000)
|
|
libpthread.so.0 => /lib/libpthread.so.0 (0x4057d000)
|
|
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
|
|
|
|
2. You may also double check that libGL.so is in fact DRI-capable. Run
|
|
strings libGL.so.1.2 | grep DRI and look for symbols prefixed with
|
|
"XF86DRI", such as "XF86DRIQueryExtension".
|
|
|
|
3. To be safe one should run ldconfig after installing libGL.so to be sure
|
|
the runtime loader will find the proper library.
|
|
|
|
4. Verify that the appropriate 3D driver is in /usr/X11R6/lib/modules/dri/
|
|
For example, the 3dfx driver will be named tdfx_dri.so.
|
|
|
|
5. Set the LIBGL_DEBUG environment variable. This will cause libGL.so to
|
|
print an error message if it fails to load a DRI driver. Any error
|
|
message printed should be self-explanatory.
|
|
|
|
6. Run glxinfo. Note the line labeled "OpenGL renderer string". It
|
|
should have a value which starts with "Mesa DRI" followed by the name
|
|
of your hardware.
|
|
|
|
7. Older Linux OpenGL applications may have been linked against Mesa's GL
|
|
library and will not automatically use libGL.so. In some cases, making
|
|
symbolic links from the Mesa GL library to libGL.so.1 will solve the
|
|
problem:
|
|
|
|
ln -s libGL.so.1 libMesaGL.so.3
|
|
|
|
In other cases, the application will have to be relinked against the
|
|
new XFree86 libGL.so.
|
|
|
|
It is reported that part of the problem is that running ldconfig will
|
|
silently rewrite symbolic links based on the SONAME field in libraries.
|
|
|
|
If you're still having trouble, look in the next section for information spe-
|
|
cific to your graphics card.
|
|
|
|
10. Hardware-Specific Information and Troubleshooting
|
|
|
|
This section presents hardware-specific information for normal use and trou-
|
|
bleshooting.
|
|
|
|
10.1 3dfx Banshee, Voodoo3, Voodoo4 and Voodoo5 Series
|
|
|
|
10.1.1 Requirements
|
|
|
|
The 3dfx DRI driver requires special versions of the 3dfx Glide library.
|
|
Different versions of Glide are needed for Banshee/Voodoo3 than for
|
|
Voodoo4/5. The Glide libraries can be downloaded from the DRI website.
|
|
|
|
10.1.2 Configuration
|
|
|
|
Your XF86Config file's device section must specify the tdfx device. For
|
|
example:
|
|
|
|
Section "Device"
|
|
Identifier "Voodoo3"
|
|
VendorName "3dfx"
|
|
Driver "tdfx"
|
|
EndSection
|
|
|
|
Or,
|
|
|
|
Section "Device"
|
|
Identifier "Voodoo5"
|
|
VendorName "3dfx"
|
|
Driver "tdfx"
|
|
EndSection
|
|
|
|
The Screen section should then reference the Voodoo device:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "Voodoo3"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 16
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
Or,
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "Voodoo5"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 24
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
Subsection "Display"
|
|
Depth 24
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
The kernel module for 3dfx hardware is named tdfx.o and should be installed
|
|
in /lib/modules/2.4.x/kernel/drivers/char/drm/. It will be automatically
|
|
loaded by the Xserver if needed.
|
|
|
|
The DRI 3D driver for 3dfx hardware should be in /usr/X11R6/lib/mod-
|
|
ules/dri/tdfx_dri.so. This will be automatically loaded by libGL.so.
|
|
|
|
The Voodoo5 supports 3D rendering in 16 and 32 bpp modes. When running in
|
|
32bpp mode an 8-bit stencil buffer and 24-bit Z (depth) buffer are offered.
|
|
When running in 16bpp mode only a 16-bit Z (depth) buffer is offered and
|
|
stencil is implemented in software.
|
|
|
|
A software-based accumulation buffer is available in both 16 and 32bpp modes.
|
|
|
|
10.1.3 Troubleshooting
|
|
|
|
o If you try to run an OpenGL application and see an error message similar
|
|
to
|
|
|
|
gd error (glide): gd error (glide): grSstSelect: non-existent SSTgd error (glide): grSstSelect: non-existent SSTS
|
|
|
|
it means that you have the wrong version of the Glide library for your
|
|
hardware.
|
|
|
|
o 3D acceleration for Banshee and Voodoo3 is only supported in the 16
|
|
bit/pixel screen mode. Use xdpyinfo to verify that all your visuals are
|
|
depth 16. Edit your XF86Config file if needed.
|
|
|
|
o The /dev/3dfx device is not used for DRI; it's only for Glide on older
|
|
3dfx hardware.
|
|
|
|
o Different versions of Glide are needed for Voodoo3 and Voodoo5. See the
|
|
DRI website's resources page to download the right version of Glide.
|
|
|
|
o Voodoo4/5 may be run at 24bpp (instead of 32bpp, the default) but 3D
|
|
acceleration is not supported in that mode. 32bpp mode is fully 3D
|
|
accelerated.
|
|
|
|
10.1.4 Performance and Features
|
|
|
|
o Normally, buffer swapping in double-buffered applications is synchro-
|
|
nized to your monitor's refresh rate. This may be overridden by setting
|
|
the FX_GLIDE_SWAPINTERVAL environment variable. The value of this vari-
|
|
able indicates the maximum number of swap buffer commands can be
|
|
buffered. Zero allows maximum frame rate.
|
|
|
|
o On Voodoo4/5, rendering with 16-bits/texel textures is faster than using
|
|
32-bit per texel textures. The internalFormat parameter to glTexImage2D
|
|
can be used to control texel size. Quake3 and other games let you con-
|
|
trol this as well.
|
|
|
|
o The glTexEnv mode GL_BLEND is not directly supported by the Voodoo3
|
|
hardware. It can be accomplished with a multipass algorithm but it's
|
|
not implemented at this time. Applications which use that mode, such as
|
|
the Performer Town demo, may become sluggish when falling back to soft-
|
|
ware rendering to render in that mode.
|
|
|
|
o The Voodoo3/Banshee driver reverts to software rendering under the fol-
|
|
lowing conditions:
|
|
|
|
o Setting GL_LIGHT_MODEL_COLOR_CONTROL to GL_SEPARATE_SPECULAR_COLOR.
|
|
|
|
o Enabling line stippling or polygon stippling.
|
|
|
|
o Enabling point smoothing or polygon smoothing.
|
|
|
|
o Enabling line smoothing when line width is not 1.0. That is,
|
|
antialiased lines are done in hardware only when the line width is
|
|
1.0.
|
|
|
|
o Using 1-D or 3-D texture maps.
|
|
|
|
o Using the GL_BLEND texture environment.
|
|
|
|
o Using stencil operations.
|
|
|
|
o Using the accumulation buffer.
|
|
|
|
o Using glBlendEquation(GL_LOGIC_OP).
|
|
|
|
o Using glDrawBuffer(GL_FRONT_AND_BACK).
|
|
|
|
o Using glPolygonMode(face, GL_POINT) or glPolygonMode(face,
|
|
GL_LINE).
|
|
|
|
o Using point size attenuation (i.e. GL_DISTANCE_ATTENUATION_EXT).
|
|
|
|
o Using glColorMask(r, g, b, a) when r!=g or g!=b.
|
|
|
|
o The Voodoo5 driver reverts to software rendering under the same condi-
|
|
tions Voodoo3 with three exceptions. First, stencil operations are
|
|
implemented in hardware when the screen is configured for 32 bits/pixel.
|
|
Second, the GL_BLEND texture env mode is fully supported in hardware.
|
|
Third, glColorMask is fully supported in hardware when the screen is
|
|
configured for 32 bits/pixel.
|
|
|
|
o As of January, 2001 the second VSA-100 chip on the Voodoo5 is not yet
|
|
operational. Therefore, the board isn't being used to its full capac-
|
|
ity. The second VSA-100 chip will allow Scan-Line Interleave (SLI) mode
|
|
for full-screen applications and games, potentially doubling the sys-
|
|
tem's fill rate. When the second VSA-100 chip is activated glGet-
|
|
String(GL_RENDERER) will report Voodoo5 instead of Voodoo4.
|
|
|
|
o The lowest mipmap level is sometimes miscolored in trilinear- sampled
|
|
polygons.
|
|
|
|
o The GL_EXT_texture_env_combine extension is supported on the Voodoo4 and
|
|
Voodoo5.
|
|
|
|
10.1.5 Known Problems
|
|
|
|
o The lowest mipmap level is sometimes miscolored in trilinear- sampled
|
|
polygons (Voodoo3/Banshee).
|
|
|
|
o Fog doesn't work with orthographic projections.
|
|
|
|
o The accuracy of blending operations on Voodoo4/5 isn't always very good.
|
|
If you run Glean, you'll find some test failures.
|
|
|
|
o The Glide library cannot be used directly; it's only meant to be used
|
|
via the tdfx DRI driver.
|
|
|
|
o SSystem has problems because of poorly set near and far clipping planes.
|
|
The office.unc Performer model also suffers from this problem.
|
|
|
|
10.2 Intel i810
|
|
|
|
10.2.1 Requirements
|
|
|
|
A kernel with AGP GART support (such as Linux 2.4.x) is needed.
|
|
|
|
10.2.2 Configuration
|
|
|
|
Your XF86Config file's device section must specify the i810 device, and spec-
|
|
ify a usable amount of video ram to reserve.
|
|
|
|
Section "Device"
|
|
Identifier "i810"
|
|
VendorName "Intel"
|
|
Driver "i810"
|
|
Option "AGPMode" "1"
|
|
VideoRam 10000
|
|
EndSection
|
|
|
|
The Screen section should then reference the i810 device:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "i810"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 16
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
The kernel module for the i810 is named i810.o and should be installed in
|
|
/lib/modules/2.4.x/kernel/drivers/char/drm/. It will be automatically loaded
|
|
by the Xserver if needed.
|
|
|
|
The DRI 3D driver for the i810 should be in /usr/X11R6/lib/mod-
|
|
ules/dri/i810_dri.so. This will be automatically loaded by libGL.so.
|
|
|
|
10.2.3 Troubleshooting
|
|
|
|
o 3D acceleration for the i810 is only available in the 16 bit/pixel
|
|
screen mode at this time. 32bpp acceleration is not supported by this
|
|
hardware. Use xdpyinfo to verify that all your visuals are depth 16.
|
|
Edit your XF86Config file if needed.
|
|
|
|
o The i810 uses system ram for video and 3d graphics. The X server will
|
|
ordinarily reserve 4mb of ram for graphics, which is too little for an
|
|
effective 3d setup. To tell the driver to use a larger amount, specify
|
|
a VideoRam option in the Device section of your XF86Config file. A num-
|
|
ber between 10000 and 16384 seems adequate for most requirements. If
|
|
too little memory is available for DMA buffers, back and depth buffers
|
|
and textures, direct rendering will be disabled.
|
|
|
|
10.2.4 Performance and Features
|
|
|
|
Basically all of the i810 features which can be exposed through OpenGL 1.2
|
|
are implemented. However, the following OpenGL features are implemented in
|
|
software and will be slow:
|
|
|
|
o Stencil buffer and accumulation buffer operations
|
|
|
|
o Blend subtract, min/max and logic op blend modes
|
|
|
|
o glColorMask when any mask is set to false
|
|
|
|
o GL_SEPARATE_SPECULAR_COLOR lighting mode
|
|
|
|
o glDrawBuffer(GL_FRONT_AND_BACK)
|
|
|
|
o Using 1D or 3D textures
|
|
|
|
o Using texture borders
|
|
|
|
10.3 Matrox G200 and G400
|
|
|
|
10.3.1 Requirements
|
|
|
|
A kernel with AGP GART support (such as Linux 2.4.x) is needed.
|
|
|
|
10.3.2 Configuration
|
|
|
|
Your XF86Config file's device section must specify the mga device:
|
|
|
|
Section "Device"
|
|
Identifier "MGA"
|
|
VendorName "Matrox"
|
|
Driver "mga"
|
|
Option "AGPMode" "1"
|
|
VideoRam 32768
|
|
EndSection
|
|
|
|
The Screen section should then reference the MGA device:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "MGA"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 16
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
To use a 32bpp screen mode, use this Screen section instead:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "MGA"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 24
|
|
DefaultFbBpp 32
|
|
Subsection "Display"
|
|
Depth 24
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
The kernel module for the G200/G400 is named mga.o and should be installed in
|
|
/lib/modules/2.4.x/kernel/drivers/char/drm/. It will be automatically loaded
|
|
by the Xserver if needed.
|
|
|
|
The DRI 3D driver for the G200/G400 should be in /usr/X11R6/lib/mod-
|
|
ules/dri/mga_dri.so. This will be automatically loaded by libGL.so.
|
|
|
|
10.3.3 Performance and Features
|
|
|
|
Software rendering will be used under any of the following conditions:
|
|
|
|
o Using glDrawBuffer(GL_FRONT_AND_BACK).
|
|
|
|
o Using point, line, or triangle smoothing.
|
|
|
|
o Using glLogicOp.
|
|
|
|
o Using glPolygonStipple or glLineStipple.
|
|
|
|
o Using 1D or 3D textures.
|
|
|
|
o Using texture borders.
|
|
|
|
o Using glDepthFunc(GL_NEVER).
|
|
|
|
o Using the accumulation buffer.
|
|
|
|
The AGP mode may be set to 1, 2, or 4. One is used by default. Higher AGP
|
|
speeds may result in unreliable performance depending on your motherboard.
|
|
|
|
Compaq has funded the implementation of AGP accelerated ReadPixels and Draw-
|
|
Pixels in this driver. With this implementation, on a G400 drawing directly
|
|
from AGP memory (exported to the client), throughput of up to 1 GB/sec has
|
|
been measured.
|
|
|
|
Additionally Compaq's funding has produced several new extensions in Mesa,
|
|
including one (packed_depth_stencil_MESA) which enables Read/DrawPixels func-
|
|
tionality to operate directly on the packed 24/8 depth/stencil buffers of
|
|
this hardware.
|
|
|
|
In order to access this functionality, the application must ensure that all
|
|
pixel processing operations are disabled. There are in addition a fairly
|
|
complex set of rules regarding which packing/unpacking modes must be used,
|
|
and which data formats are supported, and alignment constraints. See the
|
|
files in lib/GL/mesa/src/drv/mga/DOCS for a summary of these. The extension
|
|
definitions are included in the Mesa 3.4 source distribution.
|
|
|
|
10.3.4 IRQ Assignment
|
|
|
|
There have been problems in the past with the MGA driver being very sluggish
|
|
when the DRI is enabled (to the point of being unusable.) This is caused by
|
|
the graphics card not having an interrupt assigned to it. The current DRI
|
|
trunk will attempt to detect this condition and bail out gracefully.
|
|
|
|
The solution to the above problem is to assign an interrupt to your graphics
|
|
card. This is something you must turn on in your system BIOS configuration.
|
|
Please consult your system BIOS manual for instructions on how to enable an
|
|
interrupt for your graphics card.
|
|
|
|
10.3.5 MGA HAL lib
|
|
|
|
MGAHALlib.a is a binary library Matrox has provided for use under Linux to
|
|
expose functionality for which they can not provide documentation. (For
|
|
example TV-Out requires MacroVision be enabled on the output.) This binary
|
|
library also sets the pixel/memory clocks to the optimal settings for your
|
|
Matrox card.
|
|
|
|
Currently the MGAHAL library is required for the G450 to work. You can down-
|
|
load this from the driver section on Matrox's website: www.matrox.com/mga
|
|
|
|
Here modifications to the DRI build instructions which make the mga ddx
|
|
driver use the MGAHAL library:
|
|
|
|
1.Put the following define in your host.def file
|
|
#define UseMatroxHal YES
|
|
2. Place mgaHALlib.a in the following directory
|
|
xc/programs/Xserver/hw/xfree86/drivers/mga/HALlib/
|
|
|
|
You can use DualHead on the G400/G450 DH cards by creating two device sec-
|
|
tions which both point to the same BusID. For most AGP devices the BusID
|
|
will be "PCI:1:0:0". Configure your screen section as you would normally
|
|
configure XFree86 4.x Multihead. It should be noted that currently the sec-
|
|
ond head does not support direct rendering.
|
|
|
|
10.3.6 Known Problems
|
|
|
|
None.
|
|
|
|
10.4 ATI Rage 128
|
|
|
|
10.4.1 Requirements
|
|
|
|
A kernel with AGP GART support (such as Linux 2.4.x) is needed.
|
|
|
|
10.4.2 Configuration
|
|
|
|
Your XF86Config file's device section must specify the ati device:
|
|
|
|
Section "Device"
|
|
Identifier "Rage128"
|
|
VendorName "ATI"
|
|
Driver "ati"
|
|
Option "AGPMode" "1"
|
|
Option "UseCCEFor2D" "false"
|
|
EndSection
|
|
|
|
The Screen section should then reference the Rage 128 device:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "Rage128"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 16
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
Subsection "Display"
|
|
Depth 32
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
The kernel module for the Rage 128 is named r128.o and should be installed in
|
|
/lib/modules/2.4.x/kernel/drivers/char/drm/. It will be automatically loaded
|
|
by the Xserver if needed.
|
|
|
|
The DRI 3D driver for the Rage 128 should be in /usr/X11R6/lib/mod-
|
|
ules/dri/r128_dri.so. This will be automatically loaded by libGL.so.
|
|
|
|
You may also set your screen depth to 32 for 32bpp mode.
|
|
|
|
10.4.3 Performance and Features
|
|
|
|
While PCI Rage 128 based cards are supported, they do not yet support PCI
|
|
GART, so they will not perform as well as their AGP counterparts.
|
|
|
|
For AGP cards, the AGP mode may be set to 1, 2, or 4. One is used by
|
|
default. Higher AGP speeds may result in unreliable performance depending on
|
|
your motherboard.
|
|
|
|
Note that even at 32bpp there is no alpha channel.
|
|
|
|
The following OpenGL features are implemented in software and will be slow:
|
|
|
|
o accumulation buffer operations
|
|
|
|
o stencil, when using a 16bpp screen
|
|
|
|
o Blend subtract, min/max and logic op blend modes
|
|
|
|
o GL_SEPARATE_SPECULAR_COLOR lighting mode
|
|
|
|
o glDrawBuffer(GL_FRONT_AND_BACK)
|
|
|
|
o Using 1D or 3D textures
|
|
|
|
o Using texture borders
|
|
|
|
10.4.4 Known Problems
|
|
|
|
If you experience stability problems you may try setting the UseCCEFor2D
|
|
option to true. This will effectively disable 2D hardware acceleration.
|
|
Performance will be degraded, of course.
|
|
|
|
10.5 ATI Radeon
|
|
|
|
10.5.1 Requirements
|
|
|
|
A kernel with AGP GART support (such as Linux 2.4.x) is needed.
|
|
|
|
10.5.2 Configuration
|
|
|
|
Your XF86Config file's device section must specify the ati device:
|
|
|
|
Section "Device"
|
|
Identifier "Radeon"
|
|
VendorName "ATI"
|
|
Driver "ati"
|
|
Option "AGPMode" "1"
|
|
EndSection
|
|
|
|
The Screen section should then reference the Radeon device:
|
|
|
|
Section "Screen"
|
|
Identifier "Screen 1"
|
|
Device "Radeon"
|
|
Monitor "High Res Monitor"
|
|
DefaultDepth 16
|
|
Subsection "Display"
|
|
Depth 16
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
Subsection "Display"
|
|
Depth 32
|
|
Modes "1280x1024" "1024x768" "800x600" "640x480"
|
|
ViewPort 0 0
|
|
EndSubsection
|
|
EndSection
|
|
|
|
The kernel module for the Radeon is named radeon.o and should be installed in
|
|
/lib/modules/2.4.x/kernel/drivers/char/drm/. It will be automatically loaded
|
|
by the Xserver if needed.
|
|
|
|
The DRI 3D driver for the Radeon should be in /usr/X11R6/lib/mod-
|
|
ules/dri/radeon_dri.so. This will be automatically loaded by libGL.so.
|
|
|
|
You may also set your screen depth to 32 for 32bpp mode.
|
|
|
|
10.5.3 Performance and Features
|
|
|
|
While this driver supports many of the features of ATI Radeon cards, we do
|
|
not yet fully support the card's TCL features. This work is progressing, but
|
|
is not yet ready.
|
|
|
|
The AGP mode may be set to 1, 2, or 4. One is used by default. Higher AGP
|
|
speeds may result in unreliable performance depending on your motherboard.
|
|
|
|
The following OpenGL features are implemented in software and will be slow:
|
|
|
|
o Blend subtract, blend min/max and blend logicops
|
|
|
|
o Stencil and accumulation operations
|
|
|
|
o 1D and 3D textures
|
|
|
|
o Texture borders
|
|
|
|
The GL_EXT_texture_env_combine, GL_EXT_texture_env_add and GL_EXT_tex-
|
|
ture_env_dot3 extensions are supported (or will be soon supported in the new
|
|
driver based on Mesa 3.5).
|
|
|
|
We hope to implement support for the following features in the future:
|
|
|
|
o Vertex transformation, clipping and lighting (TCL)
|
|
|
|
o Hardware stencil buffer
|
|
|
|
o Cube map textures
|
|
|
|
o 3D textures
|
|
|
|
o Three texture units
|
|
|
|
10.5.4 Known Problems
|
|
|
|
Certain (early?) revisions of the AMD Irongate chipset have AGPGART problems
|
|
which effect Radeon, and other graphics cards. The card may work unreliably,
|
|
or not work at all. If the DRM kernel module is not loaded, the 2D Xserver
|
|
may work. There's hope that this can be fixed in the future.
|
|
|
|
10.6 3DLabs Oxygen GMX 2000
|
|
|
|
The driver for this hardware was experimental and is no longer being devel-
|
|
oped or supported.
|
|
|
|
11. General Limitations and Known Bugs
|
|
|
|
11.1 OpenGL
|
|
|
|
The following OpenGL features are not supported at this time: overlays,
|
|
stereo, hardware-accelerated indirect rendering.
|
|
|
|
OpenGL-like functionality is provided with the Mesa library. XFree86 4.1.0
|
|
uses Mesa 3.4.2. Subsequent releases of XFree86 will use newer versions of
|
|
Mesa. When newer versions of Mesa are available, the 3D drivers can be
|
|
updated without reinstalling XFree86 or libGL.so.
|
|
|
|
11.2 GLX
|
|
|
|
The GLX 1.3 API is exported but none of the new 1.3 functions are opera-
|
|
tional.
|
|
|
|
The new glXGetProcAddressARB function is fully supported.
|
|
|
|
GLXPixmap rendering is only supported for indirect rendering contexts. This
|
|
is a common OpenGL limitation. Attempting to use a direct rendering context
|
|
with a GLXPixmap will result in an X protocol error.
|
|
|
|
11.3 Debugging
|
|
|
|
Debugging DRI drivers with gdb can be difficult because of the locking
|
|
involved. When debugging OpenGL applications, you should avoid stepping
|
|
inside the GL functions. If you're trying to debug a DRI driver it's recom-
|
|
mended that you do so remotely, from a second system.
|
|
|
|
11.4 Scheduling
|
|
|
|
When you run multiple GL applications at once you may notice poor time slic-
|
|
ing. This is due to an interaction problem with the Linux scheduler which
|
|
will be addressed in the future.
|
|
|
|
11.5 libGL.so and dlopen()
|
|
|
|
A number of popular OpenGL applications on Linux (such as Quake3, HereticII,
|
|
Heavy Gear 2, etc) dynamically open the libGL.so library at runtime with
|
|
dlopen(), rather than linking with -lGL at compile/link time.
|
|
|
|
If dynamic loading of libGL.so is not implemented carefully, there can be a
|
|
number of serious problems. Here are the things to be careful of in your
|
|
application:
|
|
|
|
o Specify the RTLD_GLOBAL flag to dlopen(). If you don't do this then
|
|
you'll likely see a runtime error message complaining that _glapi_Con-
|
|
text is undefined when libGL.so tries to open a hardware-specific
|
|
driver. Without this flag, nested opening of dynamic libraries does not
|
|
work.
|
|
|
|
o Do not close the library with dlclose() until after XCloseDisplay() has
|
|
been called. When libGL.so initializes itself it registers several
|
|
callbacks functions with Xlib. When XCloseDisplay() is called those
|
|
callback functions are called. If libGL.so has already been unloaded
|
|
with dlclose() this will cause a segmentation fault.
|
|
|
|
o Your application should link with -lpthread. On Linux, libGL.so uses
|
|
the pthreads library in order to provide thread safety. There is appar-
|
|
ently a bug in the dlopen()/dlclose() code which causes crashes if the
|
|
library uses pthreads but the parent application doesn't. The only
|
|
known work-around is to link the application with -lpthread.
|
|
|
|
Some applications don't yet incorporate these procedures and may fail. For
|
|
example, changing the graphics settings in some video games will expose this
|
|
problem. The DRI developers are working with game vendors to prevent this
|
|
problem in the future.
|
|
|
|
11.6 Bug Database
|
|
|
|
The DRI bug database which includes bugs related to specific drivers is at
|
|
the SourceForge DRI Bug Database
|
|
|
|
Please scan both the open and closed bug lists to determine if your problem
|
|
has already been reported and perhaps fixed.
|
|
|
|
12. Resources
|
|
|
|
12.1 Software
|
|
|
|
A collection of useful configuration files, libraries, headers, utilities and
|
|
demo programs is available from http://dri.sourceforge.net/res.phtml
|
|
|
|
12.2 Documentation
|
|
|
|
o General OpenGL information is available at the OpenGL Home Page
|
|
|
|
o XFree86 information is available at the XFree86 Home Page
|
|
|
|
o Information about the design of the DRI is available from Precision
|
|
Insight, Inc.
|
|
|
|
o Visit the DRI project on SourceForge.net for the latest development news
|
|
about the DRI and 3D drivers.
|
|
|
|
o The DRI Compilation Guide explains how to download, compile and install
|
|
the DRI for yourself.
|
|
|
|
12.3 Support
|
|
|
|
o The DRI-users mailing list at SourceForge is a forum for people to dis-
|
|
cuss DRI problems.
|
|
|
|
o In the future there may be IHV and Linux vendor support resources for
|
|
the DRI.
|
|
|
|
Generated from XFree86: xc/programs/Xserver/hw/xfree86/doc/sgml/DRI.sgml,v 1.28 dawes Exp $
|
|
|
|
|