Apollo lake GOP/VBIOS ,some monitor cannot be recognized by EDID at the bios stage.

[KLI]

Hi,

Our machine encountered some problems with HDMI display initialization failures in bios stage.

1.the screen cannot be displayed under bios setup, but the screen can be displayed under OS(win10 and ubuntu).

2. We suspected that there may be a problem with the driver(GOP/VBIOS) during the monitor detection process.

3.We measure HDMI I2C waveform and found that when the cpu via i2c ask the monitor, the monitor did not reply ack. But after the bios enters the OS the monitor will reply.

Does bios or GOP have any way to adjust the frequency of EDID signal?Such as 100KHZ to 80KHZ.

Is GOP/VBIOS possible to ignore the result of EDID and then directly output hdmi signal.

thanks!

[CarlosAM_INTEL]

Hello, @KLI​:

Thank you for contacting Intel Embedded Community.

We suggest you verify that your implementation fulfills with the guidelines stated on pages 29 and 27 of the Apollo Lake /Apollo Lake-I Dashboard document # 573991. It can be found when you are logged into your Resource & Design Center (RDC) privileged account at the following website:

http://www.intel.com/cd/edesign/library/asmo-na/eng/573991.htm

The RDC Account Support form is the channel to process your account update request or any inconvenience related to the provided website. It can be found at:

https://www.intel.com/content/www/us/en/forms/support/my-intel-sign-on-support.html

Best regards,

@Mæcenas_INTEL​.