How to enable 2xLVDS output on IMX8QM MEK board

[rahulM]

Hi NXP,

I want to enable 2xLVDS display on IMX8QM MEK board. 

Please let me know the steps how to enable 2xLVDS on MEK board.

I am using i.MX Linux Yocto Project BSP 5.4.47_2.2.0 Release version

Thanks and Regards,

rahulM

[AldoG]

Hello,

You may achieve this by selecting the appropriate dts.
 

imx8qm-mek.dtb -> imx8qm-mek-jdi-wuxga-lvds1-panel.dtb
 

To do this you need to do the following:

Step 1: Power on the board and press any key to stop the boot process at U-boot.

Step 2: Type the following command to modify the default DTB

=>setenv fdt_file imx8qm-mek-jdi-wuxga-lvds1-panel.dtb

Step 3: Save the environment variable by typing the command below

=> saveenv

Step 4: Boot the Linux Kernel by resetting the board or typing the command below:

=> boot

From L5.4.47_2.2.0/i.MX_Linux_Release_Notes
imx8qm-mek-jdi-wuxga-lvds1-panel.dtb: Supports the dual-channel LVDS panel, connecting the two mini-SAS ports with the LVDS1 CH0 and LVDS1 CH1.

Best regards,
Aldo.

[rahulM · Accepted solution]

Hi Aldo,

Thanks for your reply.

We will follow above steps for enabling 2xLVDS.

Thanks and Regards

Subramanya N M

[rahulM]

Hi Aldo,

Today i have tested for lvds dual display, i am able to see output/display only for u-boot. once kernel boots display is not showing. Only J7 connector is able to show display used lvds to hdmi converter and J2 is not showing. Please let me know how to run any sample videos on dual display after linux boots.

Please find the attachment.

I am booting device from eMMC and BSP-version i.MX Linux Yocto Project BSP 5.4.47_2.2.0 Release

J2 is not responding,  only J7  responding for u-boot.

Thanks and Regards,

rahulM

[rahulM]

Hi Aldo,

We are using lvds to hdmi converter, lvds0 CH0 is responding and lvds1 CH0 is not responding.

Please let us know how to enable both lvds0 and lvds1 CH0 for display, if we use fsl-imx8qm-mek-jdi-wuxga-lvds1-panel.dtb only lvds0 CH0 is responding and only u-boot display able to see as shown above comment. Not able to see display after kernel boots.

Observed: changed to default dtb i.e imx8qm-mek.dtb lvds0 CH0 is displaying until login prompt lvds1 CH0 is not responding.

Expected: We need to run videos on lvds0 CH0 and lvds1 CH0, please help to solve this issue. Please let us know the steps.

Thanks and Regards,

rahulM

[AldoG]

Hello,

Please note that this dtb will enable dual display in LVDS1 CH0 and LVDS1 CH1, the Mini SAS connectors are J3 & J8, please try with this two.

Best regards,
Aldo.