QML on Raspberry

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)