xref: /dragonfly/share/man/man4/drm.4 (revision b29f78b5)
1.\"	$NetBSD: drm.4,v 1.7 2009/05/12 08:16:46 wiz Exp $
2.\"
3.\" Copyright (c) 2007 Thomas Klausner
4.\" All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\"
15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25.\"
26.Dd September 13, 2013
27.Dt DRM 4
28.Os
29.Sh NAME
30.Nm drm
31.Nd Direct Rendering Manager (DRI kernel support)
32.Sh DESCRIPTION
33The
34.Tn Direct Rendering Manager
35is part of the
36.Tn Direct Rendering Infrastructure
37(see
38.Pa http://dri.freedesktop.org/ )
39for supporting video acceleration.
40For older chipsets it's used for 3d acceleration only, but newer chipsets
41may require
42.Nm
43for 2d acceleration (XVideo, EXA) as well.
44.Pp
45The
46.Nm
47drivers provide support for the following chipsets:
48.Bl -column -offset indent ".Sy ModuleXXX" ".Sy Kernel option" ".Sy Chipset"
49.It Sy Module Ta Sy "Kernel option" Ta Sy Chipset
50.It Pa i915kms.ko Ta n/a Ta Intel i915, i945, i965, G3x, G4x
51.It Pa radeon.ko Ta Cd radeondrm Ta Radeon
52.El
53.Pp
54In most cases
55.Xr Xorg 1
56will take care of loading the appropriate modules and it is not necessary to
57modify
58.Xr loader.conf 5
59or the kernel configuration to enable
60.Nm
61support.
62.Pp
63Newer versions of
64.Xr Xorg 1 ,
65like the one from
66.Xr dports 7 ,
67do a pretty good job of figuring out the right configuration on their own,
68so having no
69.Xr xorg.conf 5
70file at all is usually the best advice.
71If for some reason an
72.Xr xorg.conf 5
73is preferred, DRI must be enabled:
74.Bd -literal
75Section "DRI"
76        Group "wheel"
77        Mode 0660
78EndSection
79.Ed
80.Pp
81With KMS, DRI is always enabled since the
82.Nm
83is always required.
84.\".Pp
85.\"In order to use two graphics cards (an on-board and another
86.\"AGP/PCI/PCIe card) with DRI, a
87.\".Pa /dev/dri/card1
88.\"link to
89.\".Pa /dev/dri/card0
90.\"has to be created using
91.\".Xr devfsctl 8 .
92.Pp
93If
94.Xr Xorg 1
95acceleration fails to initialize with a
96.Dq contigmalloc_map: failed size...
97error in dmesg, the reserve of memory for DMA ran out early and should
98be increased to a sufficiently high value by setting the
99.Va vm.dma_reserved
100loader tunable.
101A read only
102.Xr sysctl 8
103variable of the same name is provided for obtaining its current value.
104.Pp
105Debugging output can be enabled and disabled by setting the
106.Xr sysctl 8
107node
108.Ar hw.dri.0.debug .
109.Sh SEE ALSO
110.Xr Xorg 1 ,
111.Xr xorg.conf 5
112.Sh HISTORY
113DRM was first available for Linux.
114Subsequently Eric Anholt ported the DRM kernel modules to
115.Fx .
116.Sh CAVEATS
117Disable AIGLX if necessary
118.Pq Pa xorg.conf :
119.Bd -literal -offset indent
120Section "ServerFlags"
121        Option  "AIGLX" "off"
122EndSection
123.\"
124.\"Section "Extensions"
125.\"        Option "Composite" "Disable"
126.\"EndSection
127.Ed
128.Pp
129.Cd options DRM_DEBUG
130can slow DRI down a lot, disable it once
131.Nm
132works.
133