Questions tagged [framebuffer]
related to Linux `fbdev` abstraction (a.k.a. Linux framebuffer), as well as to accessing the framebuffer (a part of video memory) in general
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Low resolution in the EFI/VGA early boot framebuffer/console (and in GRUB)
When I boot my Linux machine with UEFI and grub2, I get only few graphic modes (resolution modes) available. And both of them are really smaller than my monitor/screen. For example, the boot console ...
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How do I change the framebuffer resolution at runtime without legacy /dev/fb0?
I have a server in production which was booted with a 1080p widescreen monitor attached and it used that when it automatically selected that resolution for the console on boot. Currently, it is ...
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Color range for tty
THIS IS NOT A PROBLEM ABOUT XORG
I have a singleboard PC with Intel N100 with 2 HDMI ports.
When arch boots, the color range changes to limited after i915 takeing over the display from UEFI ...
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Xorg FBDEV refuses to use the specified framebuffer
I'm using Xorg with the FBDEV driver, configuration:
Section "Device"
Identifier "Device0"
Driver "fbdev"
Option "fbdev" "/dev/fb0"
...
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How to return to efifb without reboot (re activate vga console)?
When I boot my Linux machine, I have only efifb framebuffer device available at first:
[ 0.642906] efifb: probing for efifb
[ 0.642954] efifb: No BGRT, not showing boot graphics
[ 0.642957] ...
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Is it possible to get separate framebuffers for displays on Nouveau?
I'm using a simple Nvidia GPU (gt730) to run desktop system on a home server. I'm using nouveau as the GPU driver built-in on the 6.9 latest kernel.
I use FBDEV (on /dev/fb0) to run the X server. /dev/...
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How are framebuffers, graphics cards and window systems connected?
Loose TL;DR: is the framebuffer device still used in Linux today? If so, does (for example) the X window system first write to, say, /dev/fb0, and then to GPU, or does it write to GPU directly, ...
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Linux standalone OpenGL usage
I would like to ask what makes the Linux graphics stack tick and how it all works together.
So far I have understood that it works like this - the Linux kernel exposes GPU drivers through the DRM ...
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Boot linux in text mode and without framebuffer?
This used to be the default some years ago: Linux would boot up on a text console, 80x25 characters. I want to get back to that - this is for a number of servers that boot over the net (with PXE) - ...
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My embedded application doesn't receive keyboard events (Linux framebuffer/Qt+QML application/systemd service/VNC server)
I need to remotely control a Qt / QML application on an embedded ARM instrument. I intended to do that using VNC. This doesn't work. An USB keyboard plugged in the instrument doesn't work either.
NB: ...
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Booting with an NVIDIA GPU, but without nouveau
I am trying to boot a Linux system (Debian 11) with an NVIDIA GPU; I need to avoid loading the nouveau driver, which I can do if I include some options on the linux command line (in grub.cfg):
...
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How does this whole FrameBuffer, DRM, KMS stuff work in todays Linux / Kernel?
I'm confused about what is what nowadays with Linux and video support for the console interface vs X.
Do the /dev/fb* items only relate to the old original framebuffer support?
Does DRM create/support ...
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Display images using fbi on startup using systemd
I can successfully display images using the following command:
sudo fbi -T 1 /home/pi/photo-screen/photos/*.jpg -t 4
I now want to start a slide show of those pictures as soon as the Raspberry PI ...
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Cannot write to /dev/fb0 in systemd-nspawn container
I've created a systemd-nspawn container in which /dev/fb1 from the host is bound as /dev/fb0. I've set PrivateUsers=off in the .nspawn config file, and the file ownership and permissions of /dev/fb0 ...
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What is the definitive (and simplest) way to use fbi on Raspberry OS Buster to display images automatically on startup?
I have made all sorts of modifications to my ACLs and even created a photos.service that starts fbi, but it only starts, and displays 1 image before the screen goes blank.
I have other processes (web ...
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Which service creates /dev/fb0 node?
I want to update the console-setup.service to detect screen resolution using fbset -s and adjust console font size accordingly. For fbset, I need /dev/fb0 to be present, but I don't know which service ...
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Buildroot and framebuffer
I am very new to embedded programming so please have some understanding if i sound dumb.
Recently i have built a linux kernel using buildroot tool.
These are the commands i used:
make ...
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How can I get the number bytes to write per row for FrameBuffer?
Goal: I'm writing a very simple image viewer for framebuffer /dev/fb0 (something like fbi).
Current state:
My software takes the pixel resolution from /sys/class/graphics/fb0/virtual_size (such as ...
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TERM=fbterm causes box-drawing characters (by curses) get scrambled
I'm writing TUI software on fbterm using python-curses library.
To get full color in fbterm, I read it's man page and concluded I need to change environmental variable TERM to fbterm.
Man page: By ...
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Video rom part of iomem usage
Given some x86_64 linux stock kernel running one single GPU embedded into whatever pci-e extension board.
cat-ing /proc/iomem, I can realize that some space is reserved in RAM and associated to the ...
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Relationship between framebuffer and a tty
A framebuffer is a device file which allows for a simplified interface to the screen.
For example running the below code on a RaspberryPi with a HDMI display connected:
cat /dev/urandom > /dev/fb1
...
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How to stream the linux framebuffer as video over http
I have an embedded linux system (yocto based) with a framebuffer UI (no X11) and a running web server.
Now I'm asking how to "mirror" the screen contents to a web page. Think of it like a ...
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153
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Problems enabling HDMI screen framebuffer on startup for ts_calibrate
I'm running EGT on a SAMA5D4 Xplained board. It uses KMS for output to a HDMI screen. I've got a touchscreen that needs to be calibrated on the first use, I'm using ts_calibrate from tslib. I have a ...
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Debian text mode framebuffer issue - Kernel 5.14
I can't fix the startup issue I'm facing since I updated my Debian (bullseye) to backports distribution in order to get the Kernel 5.14
As per my researching it seems to be something related to the ...
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1
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765
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How do I write directly to video memory without xorg?
Kind of an odd question I know, but fifteen years ago I was able to use svgalib on some ancient version of Debian to draw directly to video memory without xorg.
To my dismay I see svgalib was pulled ...
- 487
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Frame buffer driver(altfb) not working with a 24 bit display
I am developing an embedded Linux system with a 24 bit LCD display. I use terasic linux-socfpga to compile the kernel and I want to use the altfb driver to show the desktop in LCD. For that, I copied ...
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413
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Low-Latency method to read Xorg or DRM framebuffer
I am trying to build an application that can measure the latency/processing time of graphics frameworks on Linux.
My idea is to implement simple programs that react to an input event (e.g. mouse click)...
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Got EOS from element "pipeline0" on gst fbdevsink
I'm trying to forward video file to the framebuffer on my device that has no X. I'm using gstreamer with fbdevsink plugin.
When I test it with
gst-launch-1.0 videotestsrc ! fbdevsink
it works ...
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Alpine Linux: Disable switching into framebuffer mode at boot?
We are installing a custom version of Alpine Linux on several embedded elderly PC. The monitor is connected using VGA and may not report the supported resolutions correctly, hence the GPU may choose ...
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qt5 program with "-platform linuxfb" does not reset framebuffer when crashing
We have a qt5 program running under Alpine Linux v3.14 which uses a fragile legacy library which may cause the entire program to crash. Alpine Linux switches to framebuffer mode during start up. We ...
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