Difference between revisions of "AMDGPU"

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m (Selecting the right driver: rw)
m (AMDGPU PRO: updated link to 19.10 version release notes)
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At the moment there is support for [https://www.x.org/wiki/RadeonFeature/ Volcanic Islands (VI)] (and newer) and experimental support for [https://www.phoronix.com/scan.php?page=news_item&px=AMD-AMDGPU-Released Sea Islands (CI)] and [https://www.phoronix.com/scan.php?page=news_item&px=AMDGPU-SI-Experimental-Code Southern Islands (SI)] cards. AMD has no plans to support pre-GCN GPUs.
 
At the moment there is support for [https://www.x.org/wiki/RadeonFeature/ Volcanic Islands (VI)] (and newer) and experimental support for [https://www.phoronix.com/scan.php?page=news_item&px=AMD-AMDGPU-Released Sea Islands (CI)] and [https://www.phoronix.com/scan.php?page=news_item&px=AMDGPU-SI-Experimental-Code Southern Islands (SI)] cards. AMD has no plans to support pre-GCN GPUs.
  
Owners of unsupported GPUs may use the open source [[ATI|radeon]] or the [[AMD Catalyst]] driver instead.
+
Owners of unsupported GPUs may use the open source [[radeon]] or the [[AMD Catalyst]] driver instead.
  
 
== Installation ==
 
== Installation ==
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==== Set required module parameters ====
 
==== Set required module parameters ====
 +
 +
The parameters of both {{ic|amdgpu}} and {{ic|radeon}} modules are {{ic|1=cik_support=}} and {{ic|1=si_support=}}. They can be set as a kernel parameter or in a configuration file for ''modprobe'' in {{man|5|modprobe.d}}.
 +
 +
===== Set module parameters in kernel command line =====
  
 
To enable full support for SI/CIK when using the {{ic|amdgpu}}, set the following [[kernel parameters]] to prevent the {{ic|radeon}} module from being used [http://www.phoronix.com/scan.php?page=article&item=linux-413-gcn101&num=1]:
 
To enable full support for SI/CIK when using the {{ic|amdgpu}}, set the following [[kernel parameters]] to prevent the {{ic|radeon}} module from being used [http://www.phoronix.com/scan.php?page=article&item=linux-413-gcn101&num=1]:
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* Sea Islands (CIK): {{ic|1=radeon.cik_support=0 amdgpu.cik_support=1}}
 
* Sea Islands (CIK): {{ic|1=radeon.cik_support=0 amdgpu.cik_support=1}}
  
=== AMD DC ===
+
===== Set module parameters in modprobe.d =====
 +
 
 +
Create the following configuration files for ''modprobe'' in {{ic|/etc/modprobe.d/}}. See {{man|5|modprobe.d}} for the file syntax.
  
AMD DC (display code), introduced in {{Pkg|linux}} 4.15-4.17, is a new display stack that brings support for atomic mode-setting and HDMI/DP audio.
+
For Southern Islands (SI) add the lines with option {{ic|1=si_support=}}, for Sea Islands (CIK) add those with option {{ic|1=cik_support=}}.
For more info about AMDGPU-DC, see [https://www.phoronix.com/scan.php?page=news_item&px=AMDGPU-DC-Accepted this article].
+
 
 +
{{hc|/etc/modprobe.d/amdgpu.conf|2=
 +
options amdgpu si_support=1
 +
options amdgpu cik_support=1
 +
}}
 +
 
 +
{{hc|/etc/modprobe.d/radeon.conf|2=
 +
options radeon si_support=0
 +
options radeon cik_support=0
 +
}}
  
If you are on GCN 1.1 or newer with AMDGPU and want to use DC, set {{ic|1=amdgpu.dc=1}} as [[kernel parameter]] or [[Kernel_module#Setting_module_options|module option]] when using [[KMS]].
+
Make sure {{ic|modconf}} is in the the HOOKS array in {{ic|/etc/mkinitcpio.conf}} and [[regenerate the initramfs]].
  
 
=== AMDGPU PRO ===
 
=== AMDGPU PRO ===
  
 
{{Warning|Arch Linux is officially not supported.}}
 
{{Warning|Arch Linux is officially not supported.}}
 +
{{Out of date|AMDGPU-PRO 19.10 driver [https://www.amd.com/en/support/kb/release-notes/rn-rad-lin-19-10-unified released]. Required downgrade versions may differ.}}
 
{{Note|
 
{{Note|
 
*To use the proprietary OpenCL component without AMDGPU PRO, [[install]] {{AUR|opencl-amd}} instead.
 
*To use the proprietary OpenCL component without AMDGPU PRO, [[install]] {{AUR|opencl-amd}} instead.
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See the [https://support.amd.com/en-us/kb-articles/Pages/AMDGPU-PRO-Driver-for-Linux-Release-Notes.aspx release notes] and the [https://www.phoronix.com/forums/forum/linux-graphics-x-org-drivers/amd-linux/855699-amd-representative-says-their-vulkan-linux-driver-will-be-here-soon/page6 announcement at the Phoronix forum] for more information.
 
See the [https://support.amd.com/en-us/kb-articles/Pages/AMDGPU-PRO-Driver-for-Linux-Release-Notes.aspx release notes] and the [https://www.phoronix.com/forums/forum/linux-graphics-x-org-drivers/amd-linux/855699-amd-representative-says-their-vulkan-linux-driver-will-be-here-soon/page6 announcement at the Phoronix forum] for more information.
  
A patched version of the official AMDGPU PRO driver is available as {{AUR|amdgpu-pro}} in [[AUR]].
+
A patched version of the official AMDGPU PRO driver is available as {{AUR|amdgpu-pro}}.
  
 
== Loading ==
 
== Loading ==
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=== Enable early KMS ===
 
=== Enable early KMS ===
 
+
See [[Kernel mode setting#Early KMS start]].
{{Tip|If you have problems with the resolution, [[Kernel mode setting#Forcing modes and EDID]] may help.}}
 
 
 
[[Kernel mode setting]] (KMS) is supported by the amdgpu driver, is mandatory and enabled by default.
 
 
 
KMS is typically initialized after the [[Arch boot process#initramfs|initramfs stage]]. It is possible, however, to enable KMS during the initramfs stage. To do this, add the {{ic|amdgpu}} module to the {{ic|MODULES}} line in {{ic|/etc/mkinitcpio.conf}}:
 
 
 
MODULES=(amdgpu radeon)
 
 
 
Now, regenerate the initramfs:
 
 
 
# mkinitcpio -p linux
 
 
 
The change takes effect at the next reboot.
 
  
 
== Xorg configuration ==
 
== Xorg configuration ==
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''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:
 
''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"  
+
  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 less usual vsync downsides 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]]:
 +
 
 +
{{hc|$ xrandr --props|
 +
vrr_capable: 1
 +
        range: (0, 1)
 +
}}
  
 
== Features ==
 
== Features ==
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Since Linux 4.17, it is possible to adjust clocks and voltages of the graphics card via {{Ic|1=/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 {{Ic|1=amdgpu.ppfeaturemask=0xffffffff}}.
 
Since Linux 4.17, it is possible to adjust clocks and voltages of the graphics card via {{Ic|1=/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 {{Ic|1=amdgpu.ppfeaturemask=0xffffffff}}.
  
After this, the range of allowed values must be increased to allow higher clocks than used by default. To allow the maximum GPU clock to be increased by e.g. up to 2%, run:
+
{{Note|In sysfs, paths like {{Ic|1=/sys/class/drm/...}} are just symlinks and may change between reboots. Persistent locations can be found in {{Ic|1=/sys/devices/}}, e.g. {{Ic|1=/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/}}. Adjust the commands accordingly for a reliable result.}}
echo "2" > /sys/class/drm/card0/device/pp_sclk_od
 
{{Note|Running cat {{Ic|/sys/class/drm/card0/device/pp_sclk_od}} does always return either 1 or 0, no matter the value added to it via {{Ic|echo}}.}}
 
Unlike with previous kernel versions, this alone doesn't lead to a higher clock. The values in {{Ic|pp_od_clk_voltage}} for the pstates have to be adjusted as well. It's a good idea to get the default values as a guidance by simply reading the file. In this example, the default clock is 1196MHz and a range increase by 2% allows up to 1219MHz.
 
  
To set the GPU clock for the maximum pstate 7 on a Polaris GPU to 1209MHz and 900mV voltage, run:
+
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
 
  # 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|1=Double check the entered values, as mistakes might instantly cause fatal hardware damage!}}
 
{{Warning|1=Double check the entered values, as mistakes might instantly cause fatal hardware damage!}}
 
To apply, run
 
To apply, run
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You can reset to the default values using this:
 
You can reset to the default values using this:
 
  # echo "r" > /sys/class/drm/card0/device/pp_od_clk_voltage
 
  # 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
 
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
 
  # echo 50000000 > /sys/class/drm/card0/device/hwmon/hwmon0/power1_cap
If the video card bios doesn't provide a maximum value above the default setting, you can only decrease the power limit, but not increase.
+
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.}}
 
{{Note|The above procedure was tested with a Polaris RX 560 card. There may be different behavior or bugs with different GPUs.}}
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There is also a GUI solution [https://github.com/marazmista/radeon-profile] where you can manage the "power_dpm" with {{aur|radeon-profile-git}} and {{aur|radeon-profile-daemon-git}}.
 
There is also a GUI solution [https://github.com/marazmista/radeon-profile] where you can manage the "power_dpm" with {{aur|radeon-profile-git}} and {{aur|radeon-profile-daemon-git}}.
  
=== Screen flickering ===
+
=== R9 390 series Poor Performance and/or Instability ===
 +
 
 +
If you experience issues [https://bugs.freedesktop.org/show_bug.cgi?id=91880] with a AMD R9 390 series graphics card, set {{ic|1=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 you experience flickering [https://bugzilla.kernel.org/show_bug.cgi?id=199101] add {{ic|1=amdgpu.dc=0}} to your kernel parameters.
+
If it still does not work, try disabling DPM, by setting the [[kernel parameters]] to: {{ic|1=radeon.cik_support=0 radeon.si_support=0 amdgpu.cik_support=1 amdgpu.si_support=1}}
  
=== R9 390 series Poor Performance and/or Instability ===
+
=== Freezes with "[drm] IP block:gmc_v8_0 is hung!" kernel error ===
  
If you experience issues [https://bugs.freedesktop.org/show_bug.cgi?id=91880] with a AMD R9 390 series graphics card, set {{ic|1=radeon.cik_support=0 amdgpu.cik_support=1 amdgpu.dpm=1 amdgpu.dc=1}} as [[kernel parameters]] to force DPM support.
+
If you experience freezes and kernel crashes during a GPU intensive task with the kernel error " [drm] IP block:gmc_v8_0 is hung!" [https://bugs.freedesktop.org/show_bug.cgi?id=102322], a workaround is to set {{ic|1=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 [https://bugs.freedesktop.org/show_bug.cgi?id=102322#c15].
  
=== Freezes with "[drm] IP block:gmc_v8_0 is hung!" kernel error ===
+
=== Cursor corruption ===
  
If you experience freezes and kernel crashes during a GPU intensive task with the kernel error " [drm] IP block:gmc_v8_0 is hung!" [https://bugs.freedesktop.org/show_bug.cgi?id=102322], a workaround is to set {{ic|1=amggpu.vm_update_mode=3}} as [[kernel parameters]] to force the GPUVM page tables update to be done using the CPU. Downsides are listed here [https://bugs.freedesktop.org/show_bug.cgi?id=102322#c15].
+
If you experience issues with the mouse cursor sometimes not rendering properly, set {{ic|Option "SWCursor" "True"}} in the {{ic|"Device"}} section of the {{ic|/etc/X11/xorg.conf.d/20-amdgpu.conf}} configuration file.

Revision as of 02:15, 21 April 2019

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.

Even when AMDGPU support for SI/CIK has been enabled by the kernel, the radeon driver may be used instead of the AMDGPU driver.

To make sure the amdgpu is loaded first use the following Mkinitcpio#MODULES array, e.g. MODULES=(amdgpu radeon).

Set required module parameters

The parameters of both amdgpu and radeon modules are cik_support= and si_support=. They can be set as a kernel parameter or in a configuration file for modprobe in modprobe.d(5).

Set module parameters in kernel command line

To enable full support for SI/CIK when using the amdgpu, set the following kernel parameters to prevent the radeon module from being used [1]:

$ dmesg
[..] amdgpu 0000:01:00.0: CIK support provided by radeon.
[..] amdgpu 0000:01:00.0: Use radeon.cik_support=0 amdgpu.cik_support=1 to override.

The flags depend on the cards GCN version:

  • 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 following configuration files for modprobe in /etc/modprobe.d/. See modprobe.d(5) for the file syntax.

For Southern Islands (SI) add the lines with option si_support=, for Sea Islands (CIK) add those with option cik_support=.

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

Warning: Arch Linux is officially not supported.

Tango-view-refresh-red.pngThis article or section is out of date.Tango-view-refresh-red.png

Reason: AMDGPU-PRO 19.10 driver released. Required downgrade versions may differ. (Discuss in Talk:AMDGPU#)
Note:
  • To use the proprietary OpenCL component without AMDGPU PRO, install opencl-amdAUR instead.
  • A downgrade of the linux (4.9) and Xorg (1.18) packages is required to use AMDGPU PRO 17.10.

AMD provides a proprietary, binary userland driver called AMDGPU PRO, which works on top of the open-source AMDGPU kernel driver. The driver provides OpenGL, OpenCL, Vulkan, VA-API and VDPAU support (although this is also supported by the open-source driver). For some workloads it provides better performance than the open-source driver (example benchmark), while for others the contrary is true (example benchmark).

See the release notes and the announcement at the Phoronix forum for more information.

A patched version of the official AMDGPU PRO driver is available as amdgpu-proAUR.

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 less usual vsync downsides 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[2][3].

A workaround [4] is saving high or low in /sys/class/drm/card0/device/power_dpm_force_performance_level.

There is also a GUI solution [5] 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 [6] 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!" [7], 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 [8].

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.