01-01-2020, 07:32 PM
How does the installer set up booting when put on the MMC? The reason for this is a bit of a horror story. I wanted to try out the disk encryption, but on an SD card first.
I installed Ubuntu LXDE on the MMC using dd. This broke things pretty badly but I only found out afterwards. I could create the SD card just fine but I could not get the system to boot it. The reason was that the boot setup that comes with the Bionic image does not try to boot from the SD card, it always boots from MMC. I had taken a full image copy of my MMC, but because I could not boot from an SD card and I did not have a flasher for MMC I could not write it back.
In the end I fixed it by booting with the MMC disabled with the hardware switch and then toggling it back on before the kernel loaded. It took several tries but eventually I got the timing right and could restore the backup. If the installer sets things up so that SD card booting still works, testing this would be easier as you can boot from an LXDE card and install directly to MMC. If things don't work then doing a rollback would be simple.
I installed Ubuntu LXDE on the MMC using dd. This broke things pretty badly but I only found out afterwards. I could create the SD card just fine but I could not get the system to boot it. The reason was that the boot setup that comes with the Bionic image does not try to boot from the SD card, it always boots from MMC. I had taken a full image copy of my MMC, but because I could not boot from an SD card and I did not have a flasher for MMC I could not write it back.
In the end I fixed it by booting with the MMC disabled with the hardware switch and then toggling it back on before the kernel loaded. It took several tries but eventually I got the timing right and could restore the backup. If the installer sets things up so that SD card booting still works, testing this would be easier as you can boot from an LXDE card and install directly to MMC. If things don't work then doing a rollback would be simple.