i.MX ProcessorsのトピックRe: How does IMX8MQ force HDMI output?

How does IMX8MQ force HDMI output?

ximenbingmeng — Wed, 03 Jul 2024 14:21:47 GMT

When used normally, we usually read the edid, but our screen has a non-standard resolution and we can only set the timing ourselves. Based on the IMX8MQ chip and kernel version 5.10.72, do you have any reference materials? Thank you very much!

Re: How does IMX8MQ force HDMI output?

brian14 — Wed, 03 Jul 2024 17:46:07 GMT

Hi @ximenbingmeng,

Thank you for contacting NXP Support!

Could you please give more details about your requirement?
Are you trying to set an HDMI display for iMX8MQ?

Re: How does IMX8MQ force HDMI output?

ximenbingmeng — Thu, 04 Jul 2024 03:29:59 GMT

We originally used kernel 4.14.98, and all of our research was based on kernel 4.14.98, including the HDMI forced output part based on the IMX8MQ chip; Originally, we referred to the post on the following link in the forum
[Driving a 1080x1920 portal HDMI screen.]
https://community.nxp.com/t5/i-MX-Graphics/Driving-a-1080x1920-portrait-HDMI-screen/m-p/1213323
[HDMI DRM custom resolution and clock frequency]
https://community.nxp.com/t5/i-MX-Processors/HDMI-DRM-custom-resolution-and-clock-frequency/m-p/1029696
The document is attached,
However, in order to achieve the function of dual screen display, we upgraded the kernel version to kernel 5.10.2, which can now light up two screens. However, I found that the architecture of kernel 5.10.2 has undergone significant changes compared to the previous one. How can the HDMI driver be modified to achieve forced output?

Re: How does IMX8MQ force HDMI output?

brian14 — Tue, 09 Jul 2024 18:53:02 GMT

Hi @ximenbingmeng,

Thank you for your reply!

I have reviewed the case, but I couldn't find any specific materials to achieve your requirements.
In this case, you may need to refer to the IMX Reference Manual as is suggested by my colleague in your other thread.
HDMI interface forced output based on IMX8MQ chip - NXP Community