IMX6Q Start X server Failed With Segmentation Fault Error

[yuklin_soo]

Hi there,

I am currently working to enable X-server on a customized IMX6Q board and I am using kernel version 3.14.52.  The IMX6Q target board is using an LVDS panel as a system console, when the system boots up, I can see boot messages on the screen, but the screen is blanked just before the login prompt appears.

After some investigations, it was found that during the initialization of X-server, the below commands in the init script file “/etc/init.d/xserver-nodm”:

       echo "Starting Xserver"

      . /etc/X11/xserver-common

      xinit /etc/X11/Xsession -- `which $XSERVER` $ARGS >/var/log/Xsession.log 2>&1

is causing the “xf86-video-imxfb-vivante” driver  to call ioctl(fdDev, FBIOBLANK, FB_BLANK_NORMAL) to turn off the LVDS screen.  I had to run the command

# echo 0 > /sys/class/graphics/fb0/blank

on the serial console to turn on the LVDS screen again.

Running the command “startx” will also turn off the LVDS screen.

The log file /var/log/Xorg.0.log (attached) shows that during the initialization of EXA driver, the start X process failed with error “Segmentation fault at address 0xe0”.

[1881882.947] (II) VIVANTE(0): test Initializing EXA

[1881882.947] (II) VIVANTE(0): (driver build from: -dirty)

[1881882.953] (II) EXA(0): Driver allocated offscreen pixmaps

[1881882.953] (II) EXA(0): Driver registered support for the following operations:

[1881882.953] (II)         Solid

[1881882.953] (II)         Copy

[1881882.953] (II)         Composite (RENDER acceleration)

[1881882.953] (II)         UploadToScreen

[1881882.953] (EE)

[1881882.953] (EE) Backtrace:

[1881882.954] (EE)

[1881882.954] (EE) Segmentation fault at address 0xe0

[1881882.954] (EE)

Fatal server error:

[1881882.954] (EE) Caught signal 11 (Segmentation fault). Server aborting

[1881882.954] (EE)

[1881882.954] (EE)

Please consult the The X.Org Foundation support

         at http://wiki.x.org

 for help.

[1881882.954] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.

[1881882.955] (EE)

[1881882.978] (EE) Server terminated with error (1). Closing log file.

In my build environment, the below kernel options are enabled:

CONFIG_DRM_VIVANTE=y

CONFIG_MXC_GPU_VIV=y

and the “xf86-video-imxfb-vivante” package that I am using is of version “5.0.11.p4.5”.

$ ls -l xf86-video-imxfb-vivante_5.0.11.p4.5.bb
-rw-r--r-- 1 ylsoo ylsoo 349 Dec 28 2015 xf86-video-imxfb-vivante_5.0.11.p4.5.bb

$

Can this version support the IMX6Q Vivante GPU? Should I upgrade it to a newer version?

Really appreciate if someone could provide any advice or solution to this problem.

[Bio_TICFSL]

Hello Alex,

The 3.14.52 is not supported anymore, you can migrate to 4.9.88v where vivante drivers are more stable. BTW you are using fb or X11? The following link show you how to run the x11:

https://community.nxp.com/docs/DOC-330147 

Hope this helps

[yuklin_soo]

Thank you for the reply. I am using X11 here.

Initially, I was using kernel version 3.14.28 with Yocto release "Fido" on my IMX6Q target board, and later I upgraded it to kernel version 3.14.52 per request. On the process, I make a mistake that i just updated my personal meta layer to check out and compile 3.14.52 source codes, but in the meantime, I did not know there is also a need to update my build environment (Yocto meta layers) from " Fido" to  "Jethro" release which seems more compatible with the 3.14.52 kernel.  I just realised that a while ago and I updated my build environment to "Jethro" and recompiled the image to boot up my target board and the X-server started up successfully. One difference noticed is that the "Fido" release is using Vivante driver of version 5.0.11.p4.5, whereas, the "Jethro" is using version 5.0.11.p7.4. It looks like the newer version 5.0.11.p7.4 is able to support the IMX6Q Vivante GPU.