Hello.
I have a project underway in which I'd like to run a graphical environment on an official 7" Touch Display 2 connected to a PI 5, but using buildroot to configure the linux image.
However, I'm having trouble getting the desktop running. I'm able to see the boot logs and console BUT only through HDMI; the touch screen is remains black. I cannot get weston to run, even through HDMI.
Here is how I'm configuring things:
Buildroot setup
* start with pi5 default config
* changed root fs to 256M
* changed init system from busybox to systemd
* enable mesa3D and:
---- gallium vc4 driver, vulkan broadcom, nouveau, gallium v3d
---- OpenGL ES
* enable sway
* enable nano
* enable sdl2, openGL ES, KMS/DRM video driver, Wayland video driver
* enabled weston, simple client, demo client
Then to the SD card's config.txt, I add:
```
# Automatically load overlays for detected DSI displays
display_auto_detect=1
# Enable DRM VC4 V3D driver
dtoverlay=vc4-kms-v3d
```
Once booted
* I login as root (no password; just for testing!)
* `mkdir -p /run/user/0 && chmod 700 /run/user/0` (required because weston complains about a missing XDG runtime dir otherwise)
* `XDG_RUNTIME_DIR=/run/user/0 weston`
The command runs but immediately exits, with the following info (handwritten; some lines omitted):
```
Initializing drm backend
Created VT-bound seat seat0
New client connected (pid: 174, uid: 0, gid: 0)
Started embedded seatd
Added client 1 to seat0
Removed client 1 seat0vateuiltin [sic]
Client disconnected
Failed to create compositor backend
```
Trying to run sway (``XDG_RUNTIME_DIR=/run/user/0 sway`) is not successful, either, returning `Unable to create backend any DRM deviceackend` [sic]. However, sway isn't required, I just thought I'd try.
In short, my question is how I should configure buildroot/config.txt to show a desktop? In the first instance, I don't mind it just running via HDMI, but eventually I would like to run it on the touch display.
P.s. the longterm hope to run an imgui app using a buildroot build, which might just need SDL2 and not a compositor; I'm not there yet... but I'm interested in just getting a desktop to run regardless!
I have a project underway in which I'd like to run a graphical environment on an official 7" Touch Display 2 connected to a PI 5, but using buildroot to configure the linux image.
However, I'm having trouble getting the desktop running. I'm able to see the boot logs and console BUT only through HDMI; the touch screen is remains black. I cannot get weston to run, even through HDMI.
Here is how I'm configuring things:
Buildroot setup
* start with pi5 default config
* changed root fs to 256M
* changed init system from busybox to systemd
* enable mesa3D and:
---- gallium vc4 driver, vulkan broadcom, nouveau, gallium v3d
---- OpenGL ES
* enable sway
* enable nano
* enable sdl2, openGL ES, KMS/DRM video driver, Wayland video driver
* enabled weston, simple client, demo client
Then to the SD card's config.txt, I add:
```
# Automatically load overlays for detected DSI displays
display_auto_detect=1
# Enable DRM VC4 V3D driver
dtoverlay=vc4-kms-v3d
```
Once booted
* I login as root (no password; just for testing!)
* `mkdir -p /run/user/0 && chmod 700 /run/user/0` (required because weston complains about a missing XDG runtime dir otherwise)
* `XDG_RUNTIME_DIR=/run/user/0 weston`
The command runs but immediately exits, with the following info (handwritten; some lines omitted):
```
Initializing drm backend
Created VT-bound seat seat0
New client connected (pid: 174, uid: 0, gid: 0)
Started embedded seatd
Added client 1 to seat0
Removed client 1 seat0vateuiltin [sic]
Client disconnected
Failed to create compositor backend
```
Trying to run sway (``XDG_RUNTIME_DIR=/run/user/0 sway`) is not successful, either, returning `Unable to create backend any DRM deviceackend` [sic]. However, sway isn't required, I just thought I'd try.
In short, my question is how I should configure buildroot/config.txt to show a desktop? In the first instance, I don't mind it just running via HDMI, but eventually I would like to run it on the touch display.
P.s. the longterm hope to run an imgui app using a buildroot build, which might just need SDL2 and not a compositor; I'm not there yet... but I'm interested in just getting a desktop to run regardless!
Statistics: Posted by zerooneone — Fri Dec 05, 2025 12:09 pm