Does the dual screen display based on the IMX8MQ chip support dual interface display of QT software?

[ximenbingmeng]

Hello,

we can see from the reference manual that the block diagram for achieving "dual screen display" is as follows,

And I saw the following explanation,

So if QT is in a "flow" mode, wouldn't displaying two QT interfaces work? If feasible, are there any reference examples? The kernel version we are using is 5.10.72.
Looking forward to your reply, thank you very much!

[gary_bisson]

Hi,

As far as I know it isn't possible as the i.MX 8MQ exposes 2 different DRM/KMS devices for each output, 1DCSS & 1LCDIF.

All Qt examples show multiple displays examples using 1 and only 1 DRM device:

https://doc.qt.io/qt-6/embedded-linux.html#active-outputs-and-qscreen-instances

That would work on the i.MX 8MP as it exposes 1 DRM/KMS device with several connectors/outputs (HDMI, LVDS, MIPI-DSI).

Regards

[ximenbingmeng]

Can IMX8MQ's DCSS connect multiple outputs? For example, connecting HDMI and MIPI-DSI? Can this achieve multi screen display?

[gary_bisson]

No the DCSS can only connect to 1 output at a time.