Troubles while flashing UEFI images

jbaptiste

Hi,

I am facing some troubles when flashing my UP board with UEFI images. I am booting on a live image (Ubuntu for instance) and do a dd of my image to the mmcblk0.

Sometimes it works properly but sometimes I am getting a kernel panic or GRUB is stuck on first startup. Reflashing exactly the same image again to the mmc solves the issue. I have also tried to do a dd if=/dev/zero of=/dev/mmcblk0 before flashing my image but I still observe the problem.

It seems that the result of flashing an UEFI image to the mmc is inconsistent in my case.

Does anybody face this issue? What is the right way to flash an uefi image to the board?

Regards,

ccalde

Hi @jbaptiste ,

If you want to work with the dd command, I would recommend you to use it for flashing in a USB stick:
sudo dd if=your_image.iso of=/dev/sdX
Where X is your defined USB device in the system.

Then, you could install the OS from the USB to the mmc.

Otherwise, you should follow the steps recommend from the UP Wiki:
https://wiki.up-community.org/Ubuntu

jbaptiste

Hello @ccalde ,

Thanks for your answer. My goal is not to install Ubuntu on the upboard but to install my own Yocto generated uefi image to the upboard.

To do so:

• I copy my uefi image to an USB drive
• I start the UP Board on Ubuntu on a live USB
• I initialize the mmcblk0 (sudo dd if=/dev/zero of=/dev/mmcblk0)
• I dd the uefi image from the USB drive to the mmcbk0 (sudo dd if=usb_drive_mounted_point/myimage.uefiimg of=/dev/mmcblk0 && sync)
• I reboot my device

When the problem appears I observe kernel panic or GRUB is stuck. If I do the same operations again it solves the problem.

I am wondering how it is possible that doing a dd of the exact same image at 2 different times might lead to different behavior. Do you have any idea?

Thanks,