BIOS not outputing 720x1280 on Apollo Lake displayport

[SLee107]

Hi Guys,

I have a question regarding to display through DP during BIOS POST.

I got a 720x1280 MIPI panel for a project and I'd like to make it as default display with my Apollo Lake board (N3350). I got a DP to MIPI converter/adapter which has been proved works with Linux Ubuntu. However, for some reason, BIOS can't recognize the panel and display nothing during POST. Is there any work around to this issue? Could it be BIOS configuration I might setup incorrectly? Any input is great appreciated.

[Virgile_V_Intel]

Uncertain of what issue might be, I recommend narrowing down possible causes first:

Does native DP display during POST?

Does DP-MIPI adapter work in OS (Win vs Linux)?

Does DP-MIPI adapter work on other platform?

Is this adapter active/passive (does it require power)?

Does the MIPI display turn on (backlight) during POST?

Is the Video BIOS/GOP VBT (BIOS vs UEFI) correctly configured?

If the MIPI display works in OS, but not under POST it may a VBT (Video BIOS Table), reach out to graphics AE to verify.

Sorry I can't give you answers, but hopefully you can find a path to head down after narrowing down what is happening.

[SLee107]

Dear vvalente,

Thank you for your reply. The OS I've tried are Ubuntu 14.04 and Yocto Linux.

The DP-mipi does shows desktop/terminal message after booting into the OS.

I've also tried Windows 10. For some reason Windows 10 is not working with my 720x1280 panel.

I forget to mention that if I change my panel to to a regular DP monitor (1080p) everything works fine.

It seems like your suggested related to VBT configuration. I contacted my Apollo Lake board FAE but he can't figure out the reason neither.

Can VBT configure to 720x1280? My FAE told me it's not possible. I wonder he gave me incorrect information.

[CarlosAM_INTEL]

Hello, hsiaolee:

Thank you for contacting Intel Embedded Community.

In order to be on the same page, we would like to address the following questions:

Could you please tell us if these consultations are related to your own design or a third party design? In case that it is a third party design, could you please give us all the information related to it? In case that it is your own design, could you please inform us if the cited can be replicated using any of the following Operating Systems (OS)?

- Windows* 10 Enterprise (64-bit)

- Windows 10 IoT Core (32/64-bit)

- Wind River 8 Linux distribution (64-bit)

- Yocto Project* BSP tool-based embedded Linux distribution (64-bit)

- Android (64-bit) Marshmallow PV April 17

- Android O PV Target Q3 '17

- Wind River VxWorks* 7

Waiting for all the information that should answer our questions.

Best regards,

Carlos_A.

[SLee107]

Dear Carlos,

The SOC module + carrier board set is third party designed. It is used to test and being reference for designing our own carrier board.

The vendor use BIOS designed by AMI.

The OS has been tested:

Windows 10 - no display on DP-mipi+720x1280 mipi panel. works on regular DP monitor (1920x1080)

Ubuntu 14.04 - works on both

Yocto Linux - works on both

BIOS - works with regular DP monitor

I think it's related to VBT. Unfortunately, my third-party vendor is not helpful. I am posting here to see if I can get more information regarding to this issue. I am not familiar with BIOS . I know in order to display DP correctly, DDC/EDID is acquired during link training. But does BIOS do similar thing when detected DP panel is connected? Or it just do display by VBT? I know the VBT I am using not consist 720x1280. 720x1280 is not regular VESA configuration. Can VBT do 720x1280?

[CarlosAM_INTEL]

Hello, hsiaolee:

Thanks for your replies.

Based on your previous communications, we would like to address the following questions:

Could you please give us the name of the manufacturer, the part number, and the rest of the information of the third party board related to this situation?

Could you please try to verify if this situation happens to a panel with DP port using any of the Operating Systems listed in my previous communication? In case that you ignore the answer, please try to reproduce the suggested scenario, and let us know the results in a detailed way.

Could you please tell us if this situation happens with different DP to MIPI converters /adapters? In case that it happens with just one, please try to other, let us know the information of the devices, and finally, inform us the results.

Please give us all the information that should answer these consultations.

We really appreciate your cooperation to solve this inconvenience.

Best regards,

Carlos_A .

[SLee107]

Dear Carlos,

I am using Arbor i2401 Apollo Lake Q7 module with Celeron N3350.

The carrier board is Arbor's new beta PCB. I don't have the part number or module number for it. Arbor lend us for experiments. Sorry there's no extra information I can provide.

I believe I already provide OS test result in my previous communication. Maybe I have not made it clear. Here's what I have tried:

- Windows* 10 Enterprise (64-bit): No display for both BIOS POST or Windows

- Windows 10 IoT Core (32/64-bit): No installation files so have not tried it.

- Wind River 8 Linux distribution (64-bit): No installation files so have not tried it.

- Yocto Project* BSP tool-based embedded Linux distribution (64-bit): No display during BIOS POST. But display was shown after booting into Yocto

- Android (64-bit) Marshmallow PV April 17: No installation files so have not tried it.

- Android O PV Target Q3 '17: No installation files so have not tried it.

- Wind River VxWorks* 7: No installation files so have not tried it.

and extra:

- Ubuntu Linux v.14.04: No display during BIOS POST. But display was shown after booting into Yocto

I only have one DP to MIPI converter so I can't provide you any more test result you've requested. However, this DP-to-MIPI converter DOES display after booting into Linux OS. This makes me think the probelm is not on DP-to-MIPI converter.

The issue is mainly on BIOS POST not OS compatibility. We are going to use Yocto for the project and we've known Yocto works with the 720x1280 MIPI panel+DP-to-MIPI converter. But we wish to have BIOS display LOGO image during POST. The issue is BIOS is not able to display anything at all. We've tried to get into BIOS setup menu but nothing displayed on 720x1280 panel. The question actually is the capability for BIOS to display 720x1280 resolution via DP. We are looking for answer or direction regarding to how the BIOS should be configured. Or maybe there's needs to have new BIOS FW consists specific graphic related SW/FW/driver which address the issue.

At last, I don't get this passage from your previous communication:

"...In case that you ignore the answer, please try to reproduce the suggested scenario..."

What is the 'answer' I've ignored? What is the 'suggested scenario' has been provided in previous communications? My English is not good. I would be grateful if you could address them specifically. Thank you.

[CarlosAM_INTEL]

Hello, hsiaolee:

Thanks for your clarification.

Based on your previous communication, we suggest you address your consultations related to the cited third-party board as a reference by filling out the form stated at the following website:

https://www.arbor-technology.com/gl/Form/ContactUs/Index/Technical%20Support https://www.arbor-technology.com/gl/Form/ContactUs/Index/Technical%20Support

Because they handle the proper information to the board related to the cited situation.

We hope that this information may help you.

Best regards,

Carlos_A.