Dual display functionality support on custom board based on iMX6 running Yocto

[alexeylugovskoy]

Hello, Everyone!

1. System description:

We are using a custom boards with iMX6Solo and iMX6Quad processors from different h/w vendors. The requirement is to bring up dual display functionality on these boards. We use standard Yocto 2.2 with layer meta-fsl-arm from git.yoctoproject.org/meta-fsl-arm and Wayland/Weston graphics packages. Weston backend uses fbdev.

Additional Weston command line options for running graphics in dual display configuration are the following:

weston --tty=1 --use-gal2d --device=/dev/fb0,/dev/fb2

Packet version:

imx-gpu-viv_5.0.11.p4.5

Kernels:

4.1.15

3.14.28

2. Problem description

 We tried to bring up dual display functionality on h/w boards and configurations described above. For all configurations we observe the the same issue - on a first display (no matter it's HDMI or LVDS/LCD) graphics work in a proper way without glitches and blinks; on a second display we always observe blinks and glitches/artifacts on open windows during cursor movement and input events. This can be reproduced with 32/16 bpp and does not depend on resolution. 

We can't determine the root cause of this problem. Has anyone successfully brought up dual display configuration using iMX6 Yocto with imx-gpu-viv_5.0.11.p4.5? Any suggestions how to workaround the issue described above?

Thanks in advance!

Alexey

[Bio_TICFSL]

Hi,

L3.14.52 has a known issue where the fbGetDisplay function called by the fbdev compositor on weston does not return a different display index, thus not being able to render on multiple screens at a time, You need to use the latest fsl_5.0.11.p4.7 Libraries to solve it.

GitHub - Freescale/kernel-module-imx-gpu-viv: FSL Community fork of Vivante i.MX GPU Linux kernel dr...

regards

[alexeylugovskoy]

Hello,

Many thanks for your feedback! Could you please clarify what version of Weston is used for mentionded imx-gpu-viv 5.0.11 8.6? The latests one seems still have issues described above. There is Weston fork to include support for Freescale i.MX (https://github.com/Freescale/weston-imx), but it's quite old and is not compatible with libinput from yocto 2.x.

Thanks,

Alexey

[Bio_TICFSL]

Please check the pacthes for weston 1.9 and Latest BSP based on 4.1.5 with gpu p8.3

https://community.nxp.com/thread/391972 

regards

[alexeylugovskoy]

Thanks! I found that similar issue has been discussed here:

https://community.nxp.com/thread/443216