We are porting rocko build for iMX6 Solo SABRE Smart Device (iMX6SolosabreSD)
BSP: fsl-bsp-relase rocko
Problem observed - Failed to start x server
MACHINE = imx6solosabresd
DISTRO = fsl-imx-x11
IMAGE = fsl-image-validation-imx
failed to start X server
X.Org X Server 1.19.3
Release Date: 2017-03-15
X Protocol Version 11, Revision 0
Build Operating System: Linux 4.4.0-174-generic x86_64
Current Operating System: Linux imx6solosabresd 4.9.88-imx_4.9.88_2.0.0_ga+g5e23f9d61147 #6 SMP PREEMPT Wed Mar 18 14:24:33 IST 2020 armv7l
Kernel command line: console=ttymxc0,115200 nosmp root=/dev/mmcblk3p2 rootwait rw
Build Date: 14 March 2020 12:48:23PM
Current version of pixman: 0.34.0
Before reporting problems, check http://wiki.x.org
to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
(++) from command line, (!!) notice, (II) informational,
(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Sat Mar 14 04:37:49 2020
(==) Using config file: "/etc/X11/xorg.conf"
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
[ 1] Failed to open device: No such file or directory, Try again...
[ 2] Failed to open device: No such file or directory, Try again...
[ 3] Failed to open device: No such file or directory, Try again...
[ 4] Failed to open device: No such file or directory, Try again...
[ 5] _OpenDevice(1229): FATAL: Failed to open device, errno=No such file or directory.
xinit: giving up
xinit: unable to connect to X server: Connection refused
xinit: server error
https://community.nxp.com/message/1086549 this will do help for you.