Compute Module 4 (CM4 Lite) Error creating SDL Window

Cythan77286

Retropie version: 4.7.1 (RPI 4/400).
LCD Connection: DPI Mode 2.
Board: Compute Module 4 – 2GB RAM (Wireless).

I am attempting to connect a 4 inch RGB DPI display to a compute module 4 (lite) and run Retropie on it with the end goal of making a handheld console.
The screen turns on and boots showing the coloured box and the initial scripts however, the issue I’m having is the emulation station fails to start and I get an error message displayed reads
“Error creating SDL window!”
“Could not initialize EGL”
“Renderer failed to initialize!”
“Window failed to initialize!”

If I connect the screen using HDMI everything works and boots up normally. Is their a work around or a solution to this problem?

my config file

# For more options and information see
# http://rpf.io/configtxt
# Some settings may impact device functionality. See link above for details

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
#disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# uncomment if hdmi display is not detected and composite is being output
#hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
#hdmi_group=1
#hdmi_mode=1

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv_mode=2

#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

# Uncomment some or all of these to enable the optional hardware interfaces
#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on

# Uncomment this to enable infrared communication.
#dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18

# Additional overlays and parameters are documented /boot/overlays/README

# Enable audio (loads snd_bcm2835)
dtparam=audio=on

# Enable USB
dtoverlay=dwc2,dr_mode=host

# Internal antenna
dtparam=ant1

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
#dtoverlay=vc4-kms-v3d
max_framebuffers=2



[all]
dtoverlay=vc4-fkms-v3d
#gpu_mem_256=128
#gpu_mem_512=256
#gpu_mem_1024=256
#overscan_scale=1

# Added to support tft screen 

# Disable spi and i2c, we need these pins.
dtparam=spi=off
dtparam=i2c_arm=off

# Set screen size and any overscan required
dtoverlay=dpi24
overscan_left=0
overscan_right=0
overscan_top=0
overscan_bottom=0

framebuffer_width=480
framebuffer_height=272

# enable the DPI display
enable_dpi_lcd=1
display_default_lcd=1

# set up the size to 480x272
dpi_group=2
dpi_mode=87

# set up the hsync/vsync/clock polarity and format
#dpi_output_format=0x7F012
dpi_output_format=0x7f012

# set up the size to 480x272
hdmi_timings=480 0 40 48 88 272 0 13 3 32 0 0 0 60 0 32000000 6

boot_delay=1

mitu

This looks like DRM/KMS is not working or is not initialized on the display. Can you move the DPI settings above the [pi4] section and see if you get a different result ?
Make sure you're using the latest Kernel/firmware - do an update for the RetroPie packages and the OS/kernel from the RetroPie-Setup.

Cythan77286

@mitu
I moved the DPI settings above the [Pi4] in the config file and got the same result as before. I then proceeded to perform an update on all installed packages and still got the same result after the update.

I next tried the configuration and physical connection that Waveshare use in one of their examples for a similar screen (link below) . However this also yielded the same result, initially boot and show colours then display the Retropie splash screen then crash back to the console.
https://www.waveshare.com/wiki/4inch_DPI_LCD_(B)

mitu

@cythan77286 said in Compute Module 4 (CM4 Lite) Error creating SDL Window:

https://www.waveshare.com/wiki/4inch_DPI_LCD_(B)

Looking at the page, it specifies that the FKMS overlay should be disabled:

Note: For Raspberry Pi 4, you need to comment out dtoverlay=vc4-fkms-V3D.

This effectively means that GPU acceleration and the KMS/DRM drivers for the Pi4 are disabled, which is not a supported configuration for RetroPie. In fact, any application (not only SDL2 applications) that need an accelerated GLES[2|3] context will fail.

Cythan77286

@mitu
That makes sense that the FKMS overlay should be enabled.

What I have observed is if I comment out "dtoverlay=vc4-fkms-v3d" the screen will run through the initial boot showing the colours and then the retropie splash screen and then crash to the console showing the error message.
However If I leave "dtoverlay=vc4-fkms-v3d" in the config file it runs through the initial boot showing the colours then the retropie splash screen then it crashes to a black screen. interestingly enough I can still connect to it over SSH but if I try to run emulationstation I get the below errors;

Oct 15 11:12:13 lvl0: Error initializing SDL!
No currently active connector found.
Oct 15 11:12:13 lvl0: Renderer failed to initialize!
Oct 15 11:12:13 lvl0: Window failed to initialize!

SergioPoverony

@cythan77286 I have too trouble,
Copy my post from raspberrypi forum

1-st
#vc4_kms_v3d
#vc4_fkms_v3d
DPI 18Bit work fine, rotate 0-90-180-270.
Screen show console but cant make (emulationstation window) GL error SDL

2-nd
vc4_kms_v3d
#vc4_fkms_v3d
DPI 18Bit work fine, rotate 0-90-180-270.
Screen show console but cant make (emulationstation window) GL error SDL

3-rt
#vc4_kms_v3d
vc4_fkms_v3d
DPI 18Bit work fine, CAN'T rotate 0-90-180-270.
Screen show console and fine work emulationstation window and etc. But cant rotate