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Visitor II
September 4, 2019
Question

DK2 output goes to HDMI and not to DSI display

  • September 4, 2019
  • 11 replies
  • 7324 views

Hi Folks,

I am building openstlinux-weston/st-image-weston image for stm32mp157c-dk2 board using newest Yocto distribution provided by STM. Everything works fine except the output goes always to HDMI (even if no cable attached). I can see bootloader splash image on DSI display. However, after couple of seconds it disappears and display remains black. If I attach HDMI display after boot is complete, I can see launcher application there. BTW, the same is happening with eglfs image.

I would appreciate any hints what might be wrong and how to debug/fix the problem.

Here is the build summary information and complete boot-log from serial console.

Regards,

Andrey.

    This topic has been closed for replies.

    11 replies

    Technical Moderator
    September 5, 2019

    Hi @AndreyN​ 

    Can you also share log when you plug / unplug HDMI cable please.

    Olivier

    Technical Moderator
    September 5, 2019

    How do you power the board ? From PC or wall adaptor ?

    Do you see red light ?

    AndreyNAuthor
    Visitor II
    September 6, 2019

    Hi @Community member​ 

    Sorry for the slow response. I was out of office yesterday.

    > Can you also share log when you plug / unplug HDMI cable please.

    Connecting/disconnecting HDMI cable does not produce any logs in /var/log/messages or dmesg .

    > How do you power the board ? From PC or wall adaptor ?

    I am powering the board from active (powered) USB hub. The socket I am using is labeled USB3.0 2.4A. This HUB also shows 0.33A current usage when the board is connected.

    > Do you see red light ?

    In fact three of them =) . The LD6 close to the USER1 button, LD4 close to CN11 (I have USB cable connected to CN11) and another red one in the middle of the board under the screen near U7 chip.

    Andrey.

    Technical Moderator
    September 6, 2019

    Hi @AndreyN​ 

    LD6 ON means power source deliver not enough current for the platform.

    This lead sometime to display problem. I noticed also in your log issue with Bluetooth.

    Can you please manage to get a good power supply ?

    Thx

    Olivier

    AndreyNAuthor
    Visitor II
    September 6, 2019

    Hi @Community member​ 

    I just tried USB wall adapter rated to 5V 2.1A output. LD6 is still ON (blinking couple of times at the beginning). Previously, there were USB camera, keyboard and mouse connected to the board. I've detached all of them, but it does not change anything. I can see bootloader splash-screen (so display seams to be ok) and during the boot it goes black. Sometimes I can see a noise on the screen (gray bars pattern with colored dots on them) but most of the time it remains just black.

    Thanks,

    Andrey.

    AndreyNAuthor
    Visitor II
    September 6, 2019

    Strange thing is that with provided SD-card DSI display works always. No problems at all despite LD6 is also ON.

    So I am suspecting software related issue with image generated by recent Yocto image. But honestly, I have no idea how to debug the problem.

    Technical Moderator
    September 6, 2019

    Thanks for feedback.

    So then could you please details software version that works and other don't work .. you build image by yourself right ?

    Changing anything in configuration ?

    Thx

    Olivier

    AndreyNAuthor
    Visitor II
    September 6, 2019

    Details about my Yocto environment could be found here on pastebin. This is what I've got doing repo sync as described in installation instructions. I built the image myself without changing any configuration.

    I just realize, that boot-log from supplied SD-card says:

    ST OpenSTLinux - Weston - (A Yocto Project Based Distro) 2.6-openstlinux-19-02-20-github-display-fix stm32mp1 ttySTM0

    In contrast, my image says:

    ST OpenSTLinux - Weston - (A Yocto Project Based Distro) 2.6-snapshot stm32mp1 ttySTM0

    I will provide more detailed version information later today.

    Technical Moderator
    September 6, 2019

    Hi @AndreyN​ 

    A 5V/3A typeC/typeC adapter is recommended to avoid any problem.

    Olivier

    AndreyNAuthor
    Visitor II
    September 6, 2019

    @Community member​ , OK I will try to find more powerful adapter.

    I am also curious whether clean build of the default weston image using recent Yocto SDK works on your site?

    Technical Moderator
    September 18, 2019

    Hello Andrey,

    the full delivery (Major one) is done every 6 months. In between, ST is providing bugfixes only in github: that way customer may take the latest fixes available and integrate wherever they like in their distribution.

    There is an easy way to make distribution package based on github, see: https://wiki.st.com/stm32mpu/wiki/OpenSTLinux_distribution#Reference_source_code

    AndreyNAuthor
    Visitor II
    September 18, 2019

    Hi @Bernard PUEL​ ,

    > There is an easy way to make distribution package based on github

    Have you read my last reply to @Community member​ in this thread? I did exactly this and it does not result in the image where DSI display is working. Have you tried to follow these steps yourself with clean Yocto distribution? Can you generate image which works on one of this "unlucky" boards?

    Regards,

    Andrey.

    Technical Moderator
    September 18, 2019

    Sorry Andrey I missed few of your comments.

    The binary with this correction (starter package) and the related patches are also available in this forum: https://community.st.com/s/question/0D50X0000ASoi2XSQR/stm32mp157cdk2-not-booting-to-weston-gtk-demo-launcher

    For the github based built, did you update the kernel receipes to point to v1.0.2 kernel ?

    AndreyNAuthor
    Visitor II
    September 18, 2019

    > Sorry Andrey I missed few of your comments.

    No problem. Taking in account the large amount of responses you are writing, it could happen. Really appreciate your help.

    > For the github based built, did you update the kernel receipes to point to v1.0.2 kernel ?

    I think no. What I did is uncomment four variables in my local.conf exactly as suggested on Wiki to switch to github. In addition I did repo update assuming that all required recipie changes will be pulled from ST's repositories. Was it wrong assumption? If it is not enough, why do not you guys update Wiki with additional steps required? Even if it only valid for "unlucky guys" I still think it worth the trouble.

    Will try to find where these kernel recipies are and switch to v1.0.2.