QML on Raspberry

sierdzio

I don't know this error, sorry. So I am only guessing, but: are you sure you have all dependencies installed, including all OpenGL drivers?

Raviphulsundar

Yes, I've installed all the dependencies.

What is the meaning of
could not open DRM device error

jeremy_k

@Raviphulsundar This looks like an error reported by the eglfs plugin, but the details aren't clear to me. Can you try running it with the qt.qpa.eglfs.kms logging category enabled?

ie $ QT_LOGGING_RULES="qt.qpa.eglfs.kms=true" program -platform eglfs

Raviphulsundar

#export QT_LOGGING_RULES=qt.qpa.*=true
#./Rectangle -platform eglfs
qt.qpa.egldeviceintegration: EGL device integration plugin keys: ("eglfs_kms_egldevice","eglfs_kms","eglfs_X11")
qt.qpa.egldeviceintegration: EGL device integration plugin keys (sorted): ("eglfs_kms","eglfs_kms_egldevice","eglfs_X11")
qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_kms"
qt.qpa.egldeviceintegration: Using EGL device integrtion "eglfs_kms"
qt.qpa.input: udev device discovery for type QFlags(0x10)
qt.qpa.input: Found matching devices ()
qt.qpa.eglfs.kms: Found the following video devices ()
Could not find DRM device!
Aborted

jeremy_k

It looks like querying libudev for DRM video devices is coming up empty. Is there anything in the /sys/class/drm/ directory on the target?

From the Qt platform plugin side, the code of interest is QDeviceDiscoveryUDev::scanConnectedDevices() in qtbase/src/platformsupport/devicediscovery/qdevicediscovery_udev.cpp

Raviphulsundar

$ls /sys/class/drm
version
$cat /sys/class/drm/version
drm 1.1.0 20060810

$ls /lib/modules/4.4.43-v7/kernel/drivers/gpu/drm/
drm_mipi_dsi.ko panel/ udl/ vc4/

$lsmod
// No drm module is loaded, However DRM module is selected in Kernel configuration.

Raviphulsundar

Now I've recompiled Kernel with
CONFIG_DRM=m
instead of
CONFIG_DRM=y

Now,
$ls /sys/class/ <---- no drm directory
$ls /lib/modules/4.4.43-v7/kernel/drivers/gpu/drm/
drm_kms_helper.ko drm.ko drm_mipi_dsi.ko panel udl vc4

$lsmod -------> no drm module loaded
#modprobe drm
//DRM module loaded

And now
$ls /sys/class/drm
version <----- Only version file

$cat /sys/class/drm/version
drm 1.1.0 20060810

jeremy_k

@Raviphulsundar I suspect you need to get the Broadcom driver for the GPU. It might already be on the system, waiting to be loaded. Unfortunately I don't know what it is called. Have you checked raspberrypi.org?

Raviphulsundar

@jeremy_k, I have checked in RaspberryPi forum for this pbm related to DRM. That thread is still unsolved.

Regarding Broadcom driver for the GPU, I could not found it in Linux config.

One thing I observed is drm module is not loading at boot time.
Does it mean that Frame Buffer modules are selected instead of DRM ?

jeremy_k

Unfortunately I don't have a pi to look at. Does the Raspbian distribution include X or some sort of gui? You can grab a copy of that, boot it, and see which modules are loaded.

There's also this article about getting Qt to run with Arch on the pi 3: http://www.chaos-reins.com/2017-01-13-qt-pi3-arch-aarch64/

Raviphulsundar

@jeremy_k ,

Initially I was trying with ARM32 installation.

Then I tried with ARM64 with BCM2837 dts. But what I observed in Buildroot that,
When I select AARCH64 (ARM64), Buildroot don't allow to select Qt Quick Controls.

Is there any issue pending with "AMR64 & QtQuick combination". ?

jsulm

@Raviphulsundar Do you have ARM64 Qt build?
Is your target system running an OS built for ARM64?

Raviphulsundar

@jsulm I've OS Built for ARM64 with Qt 5.6 but without Quick controls & QML.

jsulm

@Raviphulsundar said in QML on Raspberry:

but without Quick controls & QML

Then how did you install Qt? Maybe you just need to install Quick Controls and QML?

Raviphulsundar

@jsulm I'm making raspberry pi filesystem image through Buildroot.
In Buildroot I select the application I need along with target processor, linux kernel, etc.

When I select ARM64 architecture, option for selecting QtDeclarative, QtQuick Controls get disable.

But, I've tried with ARM32 architecture with QtDeclarative, QtQuick successfully.

But when I try to run application on EGLFS plastform, I get following error.

#./Rectangle -platform eglfs
qt.qpa.egldeviceintegration: EGL device integration plugin keys: ("eglfs_kms_egldevice","eglfs_kms","eglfs_X11")
qt.qpa.egldeviceintegration: EGL device integration plugin keys (sorted): ("eglfs_kms","eglfs_kms_egldevice","eglfs_X11")
qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_kms"
qt.qpa.egldeviceintegration: Using EGL device integrtion "eglfs_kms"
qt.qpa.input: udev device discovery for type QFlags(0x10)
qt.qpa.input: Found matching devices ()
qt.qpa.eglfs.kms: Found the following video devices ()
Could not find DRM device!
Aborted

Raviphulsundar

I've recreated rootfs & kernel image with all new combination of applications & libraries.

And now with these new setup, I could able to run my QML application.

Thanx all for the help.

Raviphulsundar

now when I run example program gallery I get following msg and application run nicely

./gallery

qt.qpa.egldeviceintegration: EGL device integration plugin keys: ("eglfs_brcm")
qt.qpa.egldeviceintegration: EGL device integration plugin keys (sorted): ("eglfs_brcm")
qt.qpa.egldeviceintegration: Trying to load device EGL integration "eglfs_brcm"
qt.qpa.egldeviceintegration: Using EGL device integration "eglfs_brcm"
qt.qpa.input: evdevkeyboard: Using device discovery
qt.qpa.input: udev device discovery for type QFlags(0x8)
qt.qpa.input: Found matching devices ("/dev/input/event1")
qt.qpa.input: Adding keyboard at "/dev/input/event1"
qt.qpa.input: Try to create keyboard handler for "/dev/input/event1" ""
qt.qpa.input: Opening keyboard at "/dev/input/event1"
qt.qpa.input: Create keyboard handler with for device "/dev/input/event1"
qt.qpa.input: Unload current keymap and restore built-in
qt.qpa.input: numlock=0 , capslock=0, scrolllock=0
qt.qpa.input: evdevmouse: Using device discovery
qt.qpa.input: udev device discovery for type QFlags(0x1|0x2)
qt.qpa.input: Found matching devices ("/dev/input/event1")
qt.qpa.input: Adding mouse at "/dev/input/event1"
qt.qpa.input: create mouse handler for "/dev/input/event1" ""
qt.qpa.input: evdevtouch: Using device discovery
qt.qpa.input: udev device discovery for type QFlags(0x2|0x4)
qt.qpa.input: Found matching devices ("/dev/input/event0")
qt.qpa.input: evdevtouch: Adding device at "/dev/input/event0"
qt.qpa.input: evdevtouch: Using device /dev/input/event0
qt.qpa.input: evdevtouch: /dev/input/event0: Protocol type B (multi)
qt.qpa.input: evdevtouch: /dev/input/event0: min X: 0 max X: 1024
qt.qpa.input: evdevtouch: /dev/input/event0: min Y: 0 max Y: 600
qt.qpa.input: evdevtouch: /dev/input/event0: min pressure: 0 max pressure: 0
qt.qpa.input: evdevtouch: /dev/input/event0: device name: BYZHYYZHY By ZH851
qt.qpa.input: evdevtouch: Updating QInputDeviceManager device count: 1 touch devices, 0 pending handler(s)