iMX8 Family DisplayPort

[sbertrand]

Hi,

I would like to better understand DisplayPort support on the iMX8 product family.

The imx-yocto-L4.14.98_2.0.0_ga release documentation i.MX Linux Reference Manual present HDMI Support for i.MX 8M Quad and i.MX 8QuadMax as "HDMI 2.0/Display Port 1.3 on chip".

Is there a difference between the iMX8M and iMX8 series HDMI/DisplayPort subsystem ?

When building the boot firmware for iMX8M, I notice reference to HDMI / DisplayPort :

- ./mkimage_imx8 -fit -signed_hdmi signed_dp_imx8m.bin

- ./mkimage_imx8 -fit -signed_hdmi signed_dp_imx8m.bin 

Are those firmware and initialization specific to the iMX8M (Mscale) ?

The iMX8QuadMax imx-mkimage has reference to hdmitxfw.bin and hdmirxfw.bin. The firmware-imx bundle has hdmitxfw.bin, hdmirxfw.bin and dpfw.bin. The dpfw.bin is not referenced by imx-mkimage.

Is a firmware required to enabled displayport on iMX8QM ?

Is dpfw.bin required to enable displayport on iMX8QuadMax (iMX8QM) ?

Is the difference in firmware due to a difference in HDMI/DisplayPort subsystem ?

Is the difference in firmware due to a difference in the SoC family ( iMX8M (MSCALE) vs iMX8 ) ?

Regards,

Stan

[joanxie]

the display port difference between imx8qm and imx8mq is:

i.MX 8QuadMax supports HDMI audio and on-chip HDMI hardware through MIPI pins.
i.MX 8M Quad supports HDMI through DCSS

the imx8qm is under preproduction,for the limited information, refer to the release note, if you need to test display port, you should set "hdp_file=dpfw.bin" and use Image-fsl-imx8mq-evk-epd.dtb: Display Port support

[gsa]

Hello Joan,

We are currently trying to implement Display Port on the HDMI_TX/Display Port controller on the i.MX8QM.

1) Where can I find the device tree source of Image-fsl-imx8mq-evk-epd.dtb?

2) We succeed to establish a Display Port link with the screen but the screen does not receive an input signal. We suspect the lane mapping is not correct. We use only one lane on HDMI_TX0_DATA2_EDP0_P/N. What should be the dp-lane-mapping in the device tree?

Thanks a lot,

Georges