AMDGPU

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amdgpu is the open source graphics driver for the latest AMD Radeon graphics cards.

Selecting the right driver

Depending on the card you have, find the right driver in Xorg#AMD. This page has instructions for AMDGPU and AMDGPU PRO.

At the moment there is support for Volcanic Islands (VI) (and newer) and experimental support for Sea Islands (CI) and Southern Islands (SI) cards. AMD has no plans to support pre-GCN GPUs.

Owners of unsupported GPUs may use the open source radeon or the AMD Catalyst driver instead.

Installation

Note: If coming from the proprietary Catalyst driver, see AMD Catalyst#Uninstallation first.

Install the mesa package, which provides the DRI driver for 3D acceleration.

Support for accelerated video decoding is provided by libva-mesa-driver and lib32-libva-mesa-driver for VA-API and mesa-vdpau and lib32-mesa-vdpau packages for VDPAU.

Enable Southern Islands (SI) and Sea Islands (CIK) support

The linux package enables AMDGPU support for cards of the Southern Islands (SI) and Sea Islands (CIK). When building or compiling a kernel, CONFIG_DRM_AMDGPU_SI=Y and/or CONFIG_DRM_AMDGPU_CIK=Y should be be set in the config.

Specify the correct module order

Even when AMDGPU support for SI/CIK has been enabled by the kernel, the radeon driver may be loaded before the amdgpu driver.

Make sure amdgpu has been set as first module in the Mkinitcpio#MODULES array, e.g. MODULES=(amdgpu radeon).

Set required module parameters

The module parameters of both amdgpu and radeon modules are cik_support= and si_support=.

They need to be set as kernel parameters or in a modprobe configuration file, and depend on the cards GCN version.

Tip: dmesg may indicate the correct kernel parameter to use: [..] amdgpu 0000:01:00.0: Use radeon.cik_support=0 amdgpu.cik_support=1 to override.
Set module parameters in kernel command line

Set one of the following kernel parameters:

  • Southern Islands (SI): radeon.si_support=0 amdgpu.si_support=1
  • Sea Islands (CIK): radeon.cik_support=0 amdgpu.cik_support=1
Set module parameters in modprobe.d

Create the configuration modprobe files in /etc/modprobe.d/, see modprobe.d(5) for syntax details.

For Southern Islands (SI) use option si_support=1, for Sea Islands (CIK) use option cik_support=1, e.g.:

/etc/modprobe.d/amdgpu.conf
options amdgpu si_support=1
options amdgpu cik_support=0
/etc/modprobe.d/radeon.conf
options radeon si_support=0
options radeon cik_support=0

Make sure modconf is in the the HOOKS array in /etc/mkinitcpio.conf and regenerate the initramfs.

AMDGPU PRO

AMD provides a proprietary, binary userland driver called AMDGPU PRO, which works on top of the open-source AMDGPU kernel driver.

From Radeon Software 18.50 vs Mesa 19 benchmarks article: When it comes to OpenGL games, the RadeonSI Gallium3D driver simply dominates the proprietary AMD OpenGL driver. About the only advantage to the closed-source AMD OpenGL driver is its support for GL 4.6 while RadeonSI is still limited to GL 4.5 until its SPIR-V ingestion support is completed.

Install the amdgpu-pro-libglAUR. Optionally install the lib32-amdgpu-pro-libglAUR package for 32-bit application support.

Loading

The amdgpu kernel module should load fine automatically on system boot.

If it does not happen, then:

Enable early KMS

See Kernel mode setting#Early KMS start.

Xorg configuration

Xorg will automatically load the driver and it will use your monitor's EDID to set the native resolution. Configuration is only required for tuning the driver.

If you want manual configuration, create /etc/X11/xorg.conf.d/20-amdgpu.conf, and add the following:

/etc/X11/xorg.conf.d/20-amdgpu.conf
Section "Device"
     Identifier "AMD"
     Driver "amdgpu"
 EndSection

Using this section, you can enable features and tweak the driver settings, see amdgpu(4) first before setting driver options.

Tear Free Rendering

TearFree controls tearing prevention using the hardware page flipping mechanism. If this option is set, the default value of the property is 'on' or 'off' accordingly. If this option isn't set, the default value of the property is auto, which means that TearFree is on for rotated outputs, outputs with RandR transforms applied and for RandR 1.4 slave outputs, otherwise off:

Option "TearFree" "true"

DRI level

DRI sets the maximum level of DRI to enable. Valid values are 2 for DRI2 or 3 for DRI3. The default is 3 for DRI3 if the Xorg version is >= 1.18.3, otherwise DRI2 is used:

Option "DRI" "3"

Variable refresh rate

Variable refresh rate (also known as FreeSync) allows the monitor to adjust its refresh rate to the output signal. This allows for games to eliminate screen tearing with less of the usual downsides of vsync (such as stuttering):

Option "VariableRefresh" "true"
Note:
  • The monitor and GPU need to support FreeSync and be connected over DisplayPort. HDMI is not supported.
  • Only OpenGL applications can be adaptively refreshed. RADV Vulkan does not (yet) support FreeSync.
  • Mesa has blacklisted various desktop compositors, web browsers, and media players from enabling FreeSync support.

Verify vrr_capable is set to 1 using xrandr:

$ xrandr --props
vrr_capable: 1
        range: (0, 1)

Features

Video acceleration

See Hardware video acceleration.

Overclocking

Since Linux 4.17, it is possible to adjust clocks and voltages of the graphics card via /sys/class/drm/card0/device/pp_od_clk_voltage. It is however required to unlock access to it in sysfs by appending the boot parameter amdgpu.ppfeaturemask=0xffffffff.

Note: In sysfs, paths like /sys/class/drm/... are just symlinks and may change between reboots. Persistent locations can be found in /sys/devices/, e.g. /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/. Adjust the commands accordingly for a reliable result.

To set the GPU clock for the maximum pstate 7 on e.g. a Polaris GPU to 1209MHz and 900mV voltage, run:

# echo "s 7 1209 900" > /sys/class/drm/card0/device/pp_od_clk_voltage

The same procedure can be applied to the VRAM, e.g. maximum pstate 2 on Polaris 5xx series cards:

# echo "m 2 1850 850" > /sys/class/drm/card0/device/pp_od_clk_voltage
Warning: Double check the entered values, as mistakes might instantly cause fatal hardware damage!

To apply, run

# echo "c" > /sys/class/drm/card0/device/pp_od_clk_voltage

To check if it worked out, read out clocks and voltage under 3D load:

# watch -n 0.5  cat /sys/kernel/debug/dri/0/amdgpu_pm_info

You can reset to the default values using this:

# echo "r" > /sys/class/drm/card0/device/pp_od_clk_voltage

It is also possible to forbid the driver so switch to certain pstates, e.g. to workaround problems with deep powersaving pstates like flickering artifacts or stutter. To force the highest VRAM pstate on a Polaris RX 5xx card, while still allowing the GPU itself to run with lower clocks, run:

# echo "manual" > /sys/class/drm/card0/device/power_dpm_force_performance_level
# echo "2" >  /sys/class/drm/card0/device/pp_dpm_mclk

Allow only the three highest GPU pstates:

# echo "5 6 7" >  /sys/class/drm/card0/device/pp_dpm_sclk

To set the allowed maximum power consumption of the GPU to e.g. 50 Watts, run

# echo 50000000 > /sys/class/drm/card0/device/hwmon/hwmon0/power1_cap

Until Linux kernel 4.20, it will only be possible to decrease the value, not increase.

Note: The above procedure was tested with a Polaris RX 560 card. There may be different behavior or bugs with different GPUs.

Enable GPU display scaling

Tango-go-next.pngThis article or section is a candidate for moving to xrandr.Tango-go-next.png

To avoid the usage of the scaler which is built in the display, and use the GPU own scaler instead, when not using the native resolution of the monitor, execute:

$ xrandr --output "<output>" --set "scaling mode" "<scaling mode>"

Possible values for "scaling mode" are: None, Full, Center, Full aspect

  • To show the available outputs and settings, execute:
$ xrandr --prop
  • To set scaling mode = Full aspect for just every available output, execute:
$ for output in $(xrandr --prop | grep -E -o -i "^[A-Z\-]+-[0-9]+"); do xrandr --output "$output" --set "scaling mode" "Full aspect"; done

Troubleshooting

Xorg or applications won't start

  • "(EE) AMDGPU(0): [DRI2] DRI2SwapBuffers: drawable has no back or front?" error after opening glxgears, can open Xorg server but OpenGL apps crash.
  • "(EE) AMDGPU(0): Given depth (32) is not supported by amdgpu driver" error, Xorg won't start.

Setting the screen's depth under Xorg to 16 or 32 will cause problems/crash. To avoid that, you should use a standard screen depth of 24 by adding this to your "screen" section:

/etc/X11/xorg.conf.d/10-screen.conf
Section "Screen"
       Identifier     "Screen"
       DefaultDepth    24
       SubSection      "Display"
               Depth   24
       EndSubSection
EndSection

Screen artifacts and frequency problem

Dynamic power management may cause screen artifacts to appear when displaying to monitors at higher frequencies (120+Hz) due to issues in the way GPU clock speeds are managed[1][2].

A workaround [3] is saving high or low in /sys/class/drm/card0/device/power_dpm_force_performance_level.

There is also a GUI solution [4] where you can manage the "power_dpm" with radeon-profile-gitAUR and radeon-profile-daemon-gitAUR.

R9 390 series Poor Performance and/or Instability

If you experience issues [5] with a AMD R9 390 series graphics card, set radeon.cik_support=0 radeon.si_support=0 amdgpu.cik_support=1 amdgpu.si_support=1 amdgpu.dpm=1 amdgpu.dc=1 as kernel parameters to force the use of amdgpu driver instead of radeon.

If it still does not work, try disabling DPM, by setting the kernel parameters to: radeon.cik_support=0 radeon.si_support=0 amdgpu.cik_support=1 amdgpu.si_support=1

Freezes with "[drm] IP block:gmc_v8_0 is hung!" kernel error

If you experience freezes and kernel crashes during a GPU intensive task with the kernel error " [drm] IP block:gmc_v8_0 is hung!" [6], a workaround is to set amdgpu.vm_update_mode=3 as kernel parameters to force the GPUVM page tables update to be done using the CPU. Downsides are listed here [7].

Cursor corruption

If you experience issues with the mouse cursor sometimes not rendering properly, set Option "SWCursor" "True" in the "Device" section of the /etc/X11/xorg.conf.d/20-amdgpu.conf configuration file.

If you are using xrandr for scaling and the cursor is flickering or disappearing, you may be able to fix it by setting the TearFree property: xrandr --output HDMI-A-0 --set TearFree on.