Intel graphics: Difference between revisions
m (→Weathered colors (color range problem): flag for removal) |
(→Tear-free video: title changed, common in scrolling, not video related only) |
||
Line 169: | Line 169: | ||
== Tips and tricks == | == Tips and tricks == | ||
=== | === Tearing === | ||
The SNA acceleration method causes tearing for some people. To fix this, enable the {{ic|"TearFree"}} option in the driver by adding the following line to your [[#Xorg configuration|configuration file]]: | The SNA acceleration method causes tearing for some people. To fix this, enable the {{ic|"TearFree"}} option in the driver by adding the following line to your [[#Xorg configuration|configuration file]]: |
Revision as of 06:38, 15 October 2018
Since Intel provides and supports open source drivers, Intel graphics are essentially plug-and-play.
For a comprehensive list of Intel GPU models and corresponding chipsets and CPUs, see Wikipedia:List of Intel graphics processing units.
Installation
Install the mesa package, which provides the DRI driver for 3D acceleration.
- For 32-bit application support, also install the lib32-mesa package from the multilib repository.
- For the DDX driver (which provides 2D acceleration in Xorg), install the xf86-video-intel package. (Often not recommended, see note below.)
- For Vulkan support (Ivy Bridge and newer), install the vulkan-intel package.
Also see Hardware video acceleration.
Loading
The Intel kernel module should load fine automatically on system boot.
If it does not happen, then:
- Make sure you do not have
nomodeset
orvga=
as a kernel parameter, since Intel requires kernel mode-setting. - Also, check that you have not disabled Intel by using any modprobe blacklisting within
/etc/modprobe.d/
or/usr/lib/modprobe.d/
.
Enable early KMS
Kernel mode setting (KMS) is supported by Intel chipsets that use the i915 DRM driver and is mandatory and enabled by default.
Refer to Kernel mode setting#Early KMS start for instructions on how to enable KMS as soon as possible at the boot process.
Enable GuC / HuC firmware loading
enable_gvt=1
when GuC/HuC is enabled is not supported as of linux 4.18.8. The i915 module would fail to initialize as shown in system journal.
$ journalctl
... kernel: [drm:intel_gvt_init [i915]] *ERROR* i915 GVT-g loading failed due to Graphics virtualization is not yet supported with GuC submission ... kernel: i915 0000:00:02.0: [drm:i915_driver_load [i915]] Device initialization failed (-5) ... kernel: i915: probe of 0000:00:02.0 failed with error -5 ... kernel: snd_hda_intel 0000:00:1f.3: failed to add i915 component master (-19)
For Skylake and newer processors, some video features (e.g. CBR rate control on SKL low-power encoding mode) may require the use of an updated GPU firmware, which is currently (as of 4.16) not enabled by default. Enabling GuC/HuC firmware loading can cause issues on some systems; disable it if you experience freezing (for example, after resuming from hibernation).
It is necessary to add i915.enable_guc=3
to the kernel parameters to enable both GuG and HuC firmware loading. Alternatively, if the initramfs already includes the i915
module (see Kernel mode setting#Early KMS start), you can set these options through a file in /etc/modprobe.d/
, e.g.:
/etc/modprobe.d/i915.conf
options i915 enable_guc=3
You can verify both are enabled by using dmesg:
$ dmesg
[drm] HuC: Loaded firmware i915/kbl_huc_ver02_00_1810.bin (version 2.0) [drm] GuC: Loaded firmware i915/kbl_guc_ver9_39.bin (version 9.39) i915 0000:00:02.0: GuC firmware version 9.39 i915 0000:00:02.0: GuC submission enabled i915 0000:00:02.0: HuC enabled
Alternatively, check using:
# cat /sys/kernel/debug/dri/0/i915_huc_load_status # cat /sys/kernel/debug/dri/0/i915_guc_load_status
Xorg configuration
There is no need for any configuration to run Xorg.
However, to take advantage of some driver options, you will need to create a Xorg configuration file similar to the one below:
/etc/X11/xorg.conf.d/20-intel.conf
Section "Device" Identifier "Intel Graphics" Driver "intel" EndSection
Additional options are added by the user on new lines below Driver
.
For the full list of options, see the intel(4) man page.
- You may need to indicate
Option "AccelMethod"
when creating a configuration file, even just to set it to the default method (currently"sna"
); otherwise, X may crash. - You might need to add more device sections than the one listed above. This will be indicated where necessary.
Module-based options
The i915
kernel module allows for configuration via module options. Some of the module options impact power saving.
A list of all options along with short descriptions and default values can be generated with the following command:
$ modinfo -p i915
To check which options are currently enabled, run
# systool -m i915 -av
You will note that many options default to -1, resulting in per-chip powersaving defaults. It is however possible to configure more aggressive powersaving by using module options.
Framebuffer compression (enable_fbc)
Making use of Framebuffer compression (FBC) can reduce power consumption while reducing memory bandwidth needed for screen refreshes.
To enable FBC, use i915.enable_fbc=1
as kernel parameter or set in /etc/modprobe/i915.conf
:
/etc/modprobe.d/i915.conf
options i915 enable_fbc=1
kernel: drm: not enough stolen space for compressed buffer, disabling.
Enabling frame buffer compression on pre-Sandy Bridge CPUs results in endless error messages:
$ dmesg
[ 2360.475430] [drm] not enough stolen space for compressed buffer (need 4325376 bytes), disabling [ 2360.475437] [drm] hint: you may be able to increase stolen memory size in the BIOS to avoid thisThe solution is to disable frame buffer compression which will imperceptibly increase power consumption (around 0.06 W). In order to disable it add
i915.enable_fbc=0
to the kernel line parameters. More information on the results of disabled compression can be found here.Fastboot
The goal of Intel Fastboot is to preserve the frame-buffer as setup by the BIOS or bootloader to avoid any flickering until Xorg has started [3].
To enable fastboot, set i915.fastboot=1
as kernel parameter or set in /etc/modprobe/i915.conf
:
/etc/modprobe.d/i915.conf
options i915 fastboot=1
Intel GVT-g Graphics Virtualization Support
To enable GVT support, mainly used for allowing Xen/KVM guests to access the Intel GPU of the host, the enable_gvt=1
has to be set:
/etc/modprobe.d/i915.conf
options i915 enable_gvt=1
Tips and tricks
Tearing
The SNA acceleration method causes tearing for some people. To fix this, enable the "TearFree"
option in the driver by adding the following line to your configuration file:
/etc/X11/xorg.conf.d/20-intel.conf
Section "Device" Identifier "Intel Graphics" Driver "intel" Option "TearFree" "true" EndSection
See the original bug report for more info.
- This option may not work when
SwapbuffersWait
isfalse
. - This option may increases memory allocation considerably and reduce performance. [5]
- This option is problematic for applications that are very picky about vsync timing, like Super Meat Boy.
- This option does not work with UXA acceleration method, only with SNA.
Disable Vertical Synchronization (VSYNC)
Useful when:
- Chomium/Chrome has lags and slow performance due to GPU and runs smoothly with --disable-gpu switch
- glxgears test does not show desired performance
The intel-driver uses Triple Buffering for vertical synchronization, this allows for full performance and avoids tearing. To turn vertical synchronization off (e.g. for benchmarking) use this .drirc
in your home directory:
~/.drirc
<device screen="0" driver="dri2"> <application name="Default"> <option name="vblank_mode" value="0"/> </application> </device>
Setting scaling mode
This can be useful for some full screen applications:
$ xrandr --output LVDS1 --set PANEL_FITTING param
where param
can be:
center
: resolution will be kept exactly as defined, no scaling will be made,full
: scale the resolution so it uses the entire screen orfull_aspect
: scale the resolution to the maximum possible but keep the aspect ratio.
If it does not work, try:
$ xrandr --output LVDS1 --set "scaling mode" param
where param
is one of "Full"
, "Center"
or "Full aspect"
.
KMS Issue: console is limited to small area
One of the low-resolution video ports may be enabled on boot which is causing the terminal to utilize a small area of the screen. To fix, explicitly disable the port with an i915 module setting with video=SVIDEO-1:d
in the kernel command line parameter in the bootloader. See Kernel parameters for more info.
If that does not work, try disabling TV1 or VGA1 instead of SVIDEO-1. Video port names can be listed with xrandr.
Hardware accelerated H.264 decoding on GMA 4500
The libva-intel-driver package only provides hardware accelerated MPEG-2 decoding for GMA 4500 series GPUs. The H.264 decoding support is maintained in a separated g45-h264 branch, which can be used by installing libva-intel-driver-g45-h264AUR package. Note however that this support is experimental and its development has been abandoned. Using the VA-API with this driver on a GMA 4500 series GPU will offload the CPU but may not result in as smooth a playback as non-accelerated playback. Tests using mplayer showed that using vaapi to play back an H.264 encoded 1080p video halved the CPU load (compared to the XV overlay) but resulted in very choppy playback, while 720p worked reasonably well [7]. This is echoed by other experiences [8]. Setting the preallocated video ram size higher in bios results in much better hardware decoded playback. Even 1080p h264 works well if this is done. Smooth playback (1080p/720p) works also with mpv-gitAUR in combination with ffmpeg-gitAUR and libva-intel-driver-g45-h264AUR. With MPV and the Firefox plugin "Watch with MPV"[9] it is possible to watch hardware accelerated YouTube videos.
Setting brightness and gamma
See Backlight.
Troubleshooting
SNA issues
SNA is the default acceleration method in xf86-video-intel. If you experience issues with SNA (e.g. pixelated graphics, corrupt text, etc.), try using UXA instead, which can be done by adding the following line to your configuration file:
Option "AccelMethod" "uxa"
See intel(4) under Option "AccelMethod"
.
DRI3 issues
DRI3 is the default DRI version in xf86-video-intel. On some systems this can cause issues such as this. To switch back to DRI2 add the following line to your configuration file:
Option "DRI" "2"
For the modesetting
driver, this method of disabling DRI3 does not work. Instead, one can set the environment variable LIBGL_DRI3_DISABLE=1
.
Font and screen corruption in GTK+ applications (missing glyphs after suspend/resume)
Should you experience missing font glyphs in GTK+ applications, the following workaround might help. Edit /etc/environment
to add the following line:
/etc/environment
COGL_ATLAS_DEFAULT_BLIT_MODE=framebuffer
See also FreeDesktop bug 88584.
Blank screen during boot, when "Loading modules"
If using "late start" KMS and the screen goes blank when "Loading modules", it may help to add i915
and intel_agp
to the initramfs. See Kernel mode setting#Early KMS start section.
Alternatively, appending the following kernel parameter seems to work as well:
video=SVIDEO-1:d
If you need to output to VGA then try this:
video=VGA-1:1280x800
X freeze/crash with intel driver
Some issues with X crashing, GPU hanging, or problems with X freezing, can be fixed by disabling the GPU usage with the NoAccel
option - add the following lines to your configuration file:
Option "NoAccel" "True"
Alternatively, try to disable the 3D acceleration only with the DRI
option:
Option "DRI" "False"
Baytrail complete freeze
If you are using kernel > 3.16 on Baytrail architecture and randomly encounter total system freezes, the following kernel option is a workaround until this bug is fixed in the linux kernel.
intel_idle.max_cstate=1
This is originally an Intel CPU bug that can be triggered by certain c-state transitions. It can also happen with Linux kernel 3.16 or Windows, though apparently much more rarely. The kernel option will prevent the freeze by avoiding c-state transitions but will also increase power consumption.
Adding undetected resolutions
This issue is covered on the Xrandr page.
Weathered colors (color range problem)
Kernel 3.9 contains a new default "Automatic" mode for the "Broadcast RGB" property in the Intel driver. It is almost equivalent to "Limited 16:235" (instead of the old default "Full") whenever an HDMI/DP output is in a CEA mode. If a monitor does not support signal in limited color range, it will cause weathered colors.
One can force mode e.g. xrandr --output <HDMI> --set "Broadcast RGB" "Full"
(replace <HDMI>
with the appropriate output device, verify by running xrandr
).
Unfortunately, the Intel driver does not support setting the color range through an xorg.conf.d
configuration file.
A bug report is filed and a patch can be found in the attachment.
Also there are other related problems which can be fixed editing GPU registers. More information can be found [10] and [11].
Backlight is not adjustable
If after resuming from suspend, the hotkeys for changing the screen brightness do not take effect, check your configuration against the Backlight article.
If the problem persists, try one of the following kernel parameters:
acpi_osi=Linux acpi_osi="!Windows 2012" acpi_osi=
Corruption/Unresponsiveness in Chromium and Firefox
If you experience corruption, unresponsiveness, lags or slow performance in Chromium and/or Firefox:
Kernel crashing w/kernels 4.0+ on Broadwell/Core-M chips
A few seconds after X/Wayland loads the machine will freeze and journalctl will log a kernel crash referencing the Intel graphics as below:
Jun 16 17:54:03 hostname kernel: BUG: unable to handle kernel NULL pointer dereference at (null) Jun 16 17:54:03 hostname kernel: IP: [< (null)>] (null) ... Jun 16 17:54:03 hostname kernel: CPU: 0 PID: 733 Comm: gnome-shell Tainted: G U O 4.0.5-1-ARCH #1 ... Jun 16 17:54:03 hostname kernel: Call Trace: Jun 16 17:54:03 hostname kernel: [<ffffffffa055cc27>] ? i915_gem_object_sync+0xe7/0x190 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffffa0579634>] intel_execlists_submission+0x294/0x4c0 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffffa05539fc>] i915_gem_do_execbuffer.isra.12+0xabc/0x1230 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffffa055d349>] ? i915_gem_object_set_to_cpu_domain+0xa9/0x1f0 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffff811ba2ae>] ? __kmalloc+0x2e/0x2a0 Jun 16 17:54:03 hostname kernel: [<ffffffffa0555471>] i915_gem_execbuffer2+0x141/0x2b0 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffffa042fcab>] drm_ioctl+0x1db/0x640 [drm] Jun 16 17:54:03 hostname kernel: [<ffffffffa0555330>] ? i915_gem_execbuffer+0x450/0x450 [i915] Jun 16 17:54:03 hostname kernel: [<ffffffff8122339b>] ? eventfd_ctx_read+0x16b/0x200 Jun 16 17:54:03 hostname kernel: [<ffffffff811ebc36>] do_vfs_ioctl+0x2c6/0x4d0 Jun 16 17:54:03 hostname kernel: [<ffffffff811f6452>] ? __fget+0x72/0xb0 Jun 16 17:54:03 hostname kernel: [<ffffffff811ebec1>] SyS_ioctl+0x81/0xa0 Jun 16 17:54:03 hostname kernel: [<ffffffff8157a589>] system_call_fastpath+0x12/0x17 Jun 16 17:54:03 hostname kernel: Code: Bad RIP value. Jun 16 17:54:03 hostname kernel: RIP [< (null)>] (null)
This can be fixed by disabling execlist support which was changed to default on with kernel 4.0. Add the following kernel parameter:
i915.enable_execlists=0
This is known to be broken to at least kernel 4.0.5.
Lag in Windows guests
The video output of a Windows guest in VirtualBox sometimes hangs until the host forces a screen update (e.g. by moving the mouse cursor). Removing the enable_fbc=1
option fixes this issue.
Screen flickering
Panel Self Refresh (PSR), a power saving feature used by Intel iGPUs is known to cause flickering in some instances FS#49628 FS#49371 FS#50605. A temporary solution is to disable this feature using the kernel parameter i915.enable_psr=0
.
OpenGL 2.1 with i915 driver
The update of mesa from version 13.x to 17 may break support for OpenGL 2.1 on third gen Intel GPUs (GMA3100, see here), as described in this article, reverting it back to OpenGL 1.4. However this could be restored manually by setting /etc/drirc
or ~/.drirc
options like:
/etc/drirc
<driconf> ... <device driver="i915"> <application name="Default"> <option name="stub_occlusion_query" value="true" /> <option name="fragment_shader" value="true" /> </application> </device> ... </driconf>
See also
- https://01.org/linuxgraphics/documentation (includes a list of supported hardware)