350f1d64af
- Add a general block about how to configure and test Vulkan - Add a section about switching between mesa/radv and amdvlk on AMD GPUs.
194 lines
7.5 KiB
XML
194 lines
7.5 KiB
XML
<chapter xmlns="http://docbook.org/ns/docbook"
|
|
xmlns:xlink="http://www.w3.org/1999/xlink"
|
|
xmlns:xi="http://www.w3.org/2001/XInclude"
|
|
version="5.0"
|
|
xml:id="sec-gpu-accel">
|
|
<title>GPU acceleration</title>
|
|
|
|
<para>
|
|
NixOS provides various APIs that benefit from GPU hardware
|
|
acceleration, such as VA-API and VDPAU for video playback; OpenGL and
|
|
Vulkan for 3D graphics; and OpenCL for general-purpose computing.
|
|
This chapter describes how to set up GPU hardware acceleration (as far
|
|
as this is not done automatically) and how to verify that hardware
|
|
acceleration is indeed used.
|
|
</para>
|
|
|
|
<para>
|
|
Most of the aforementioned APIs are agnostic with regards to which
|
|
display server is used. Consequently, these instructions should apply
|
|
both to the X Window System and Wayland compositors.
|
|
</para>
|
|
|
|
<section xml:id="sec-gpu-accel-opencl">
|
|
<title>OpenCL</title>
|
|
|
|
<para>
|
|
<link xlink:href="https://en.wikipedia.org/wiki/OpenCL">OpenCL</link> is a
|
|
general compute API. It is used by various applications such as
|
|
Blender and Darktable to accelerate certain operations.
|
|
</para>
|
|
|
|
<para>
|
|
OpenCL applications load drivers through the <emphasis>Installable Client
|
|
Driver</emphasis> (ICD) mechanism. In this mechanism, an ICD file
|
|
specifies the path to the OpenCL driver for a particular GPU family.
|
|
In NixOS, there are two ways to make ICD files visible to the ICD
|
|
loader. The first is through the <varname>OCL_ICD_VENDORS</varname>
|
|
environment variable. This variable can contain a directory which
|
|
is scanned by the ICL loader for ICD files. For example:
|
|
|
|
<screen><prompt>$</prompt> export \
|
|
OCL_ICD_VENDORS=`nix-build '<nixpkgs>' --no-out-link -A rocm-opencl-icd`/etc/OpenCL/vendors/</screen>
|
|
</para>
|
|
|
|
<para>
|
|
The second mechanism is to add the OpenCL driver package to
|
|
<xref linkend="opt-hardware.opengl.extraPackages"/>. This links the
|
|
ICD file under <filename>/run/opengl-driver</filename>, where it will
|
|
be visible to the ICD loader.
|
|
</para>
|
|
|
|
<para>
|
|
The proper installation of OpenCL drivers can be verified through
|
|
the <command>clinfo</command> command of the <package>clinfo</package>
|
|
package. This command will report the number of hardware devices
|
|
that is found and give detailed information for each device:
|
|
</para>
|
|
|
|
<screen><prompt>$</prompt> clinfo | head -n3
|
|
Number of platforms 1
|
|
Platform Name AMD Accelerated Parallel Processing
|
|
Platform Vendor Advanced Micro Devices, Inc.</screen>
|
|
|
|
<section xml:id="sec-gpu-accel-opencl-amd">
|
|
<title>AMD</title>
|
|
|
|
<para>
|
|
Modern AMD <link
|
|
xlink:href="https://en.wikipedia.org/wiki/Graphics_Core_Next">Graphics
|
|
Core Next</link> (GCN) GPUs are supported through the
|
|
<package>rocm-opencl-icd</package> package. Adding this package to
|
|
<xref linkend="opt-hardware.opengl.extraPackages"/> enables OpenCL
|
|
support. However, OpenCL Image support is provided through the
|
|
non-free <package>rocm-runtime-ext</package> package. This package can
|
|
be added to the same configuration option, but requires that
|
|
<varname>allowUnfree</varname> option is is enabled for nixpkgs. Full
|
|
OpenCL support on supported AMD GPUs is thus enabled as follows:
|
|
|
|
<programlisting><xref linkend="opt-hardware.opengl.extraPackages"/> = [
|
|
rocm-opencl-icd
|
|
rocm-runtime-ext
|
|
];</programlisting>
|
|
</para>
|
|
|
|
<para>
|
|
It is also possible to use the OpenCL Image extension without a
|
|
system-wide installation of the <package>rocm-runtime-ext</package>
|
|
package by setting the <varname>ROCR_EXT_DIR</varname> environment
|
|
variable to the directory that contains the extension:
|
|
|
|
<screen><prompt>$</prompt> export \
|
|
ROCR_EXT_DIR=`nix-build '<nixpkgs>' --no-out-link -A rocm-runtime-ext`/lib/rocm-runtime-ext</screen>
|
|
</para>
|
|
|
|
<para>
|
|
With either approach, you can verify that OpenCL Image support
|
|
is indeed working with the <command>clinfo</command> command:
|
|
|
|
<screen><prompt>$</prompt> clinfo | grep Image
|
|
Image support Yes</screen>
|
|
</para>
|
|
</section>
|
|
</section>
|
|
|
|
<section xml:id="sec-gpu-accel-vulkan">
|
|
<title>Vulkan</title>
|
|
|
|
<para>
|
|
<link xlink:href="https://en.wikipedia.org/wiki/Vulkan_(API)">Vulkan</link> is a
|
|
graphics and compute API for GPUs. It is used directly by games or indirectly though
|
|
compatibility layers like <link xlink:href="https://github.com/doitsujin/dxvk/wiki">DXVK</link>.
|
|
</para>
|
|
|
|
<para>
|
|
By default, if <xref linkend="opt-hardware.opengl.driSupport"/> is enabled,
|
|
<package>mesa</package> is installed and provides Vulkan for supported hardware.
|
|
</para>
|
|
|
|
<para>
|
|
Similar to OpenCL, Vulkan drivers are loaded through the <emphasis>Installable Client
|
|
Driver</emphasis> (ICD) mechanism. ICD files for Vulkan are JSON files that specify
|
|
the path to the driver library and the supported Vulkan version. All successfully
|
|
loaded drivers are exposed to the application as different GPUs.
|
|
In NixOS, there are two ways to make ICD files visible to Vulkan applications: an
|
|
environment variable and a module option.
|
|
</para>
|
|
|
|
<para>
|
|
The first option is through the <varname>VK_ICD_FILENAMES</varname>
|
|
environment variable. This variable can contain multiple JSON files, separated by
|
|
<literal>:</literal>. For example:
|
|
|
|
<screen><prompt>$</prompt> export \
|
|
VK_ICD_FILENAMES=`nix-build '<nixpkgs>' --no-out-link -A amdvlk`/share/vulkan/icd.d/amd_icd64.json</screen>
|
|
</para>
|
|
|
|
<para>
|
|
The second mechanism is to add the Vulkan driver package to
|
|
<xref linkend="opt-hardware.opengl.extraPackages"/>. This links the
|
|
ICD file under <filename>/run/opengl-driver</filename>, where it will
|
|
be visible to the ICD loader.
|
|
</para>
|
|
|
|
<para>
|
|
The proper installation of Vulkan drivers can be verified through
|
|
the <command>vulkaninfo</command> command of the <package>vulkan-tools</package>
|
|
package. This command will report the hardware devices and drivers found,
|
|
in this example output amdvlk and radv:
|
|
</para>
|
|
|
|
<screen><prompt>$</prompt> vulkaninfo | grep GPU
|
|
GPU id : 0 (Unknown AMD GPU)
|
|
GPU id : 1 (AMD RADV NAVI10 (LLVM 9.0.1))
|
|
...
|
|
GPU0:
|
|
deviceType = PHYSICAL_DEVICE_TYPE_DISCRETE_GPU
|
|
deviceName = Unknown AMD GPU
|
|
GPU1:
|
|
deviceType = PHYSICAL_DEVICE_TYPE_DISCRETE_GPU</screen>
|
|
|
|
<para>
|
|
A simple graphical application that uses Vulkan is <command>vkcube</command>
|
|
from the <package>vulkan-tools</package> package.
|
|
</para>
|
|
|
|
<section xml:id="sec-gpu-accel-vulkan-amd">
|
|
<title>AMD</title>
|
|
|
|
<para>
|
|
Modern AMD <link
|
|
xlink:href="https://en.wikipedia.org/wiki/Graphics_Core_Next">Graphics
|
|
Core Next</link> (GCN) GPUs are supported through either radv, which is
|
|
part of <package>mesa</package>, or the <package>amdvlk</package> package.
|
|
Adding the <package>amdvlk</package> package to
|
|
<xref linkend="opt-hardware.opengl.extraPackages"/> makes both drivers
|
|
available for applications and lets them choose. A specific driver can
|
|
be forced as follows:
|
|
|
|
<programlisting><xref linkend="opt-hardware.opengl.extraPackages"/> = [
|
|
<package>amdvlk</package>
|
|
];
|
|
|
|
# For amdvlk
|
|
<xref linkend="opt-environment.variables"/>.VK_ICD_FILENAMES =
|
|
"/run/opengl-driver/share/vulkan/icd.d/amd_icd64.json";
|
|
# For radv
|
|
<xref linkend="opt-environment.variables"/>.VK_ICD_FILENAMES =
|
|
"/run/opengl-driver/share/vulkan/icd.d/radeon_icd.x86_64.json";
|
|
</programlisting>
|
|
</para>
|
|
</section>
|
|
</section>
|
|
</chapter>
|