Not able to boot up from eMMC drive

[aaditya]

Hi @LucidScrubJay,

@LucidScrubJay

Seemingly trying to boot from SD even if root is clearly on the emmc. (Fresh board, but have the same behavior on old board that I tried to spi flash)

This is a designed behaviour. The bootloader checks if SD card is present, if yes tries to boot from it.

@LucidScrubJay

I can boot from emmc, but if I format an SD card for storage, the Board won’t boot after restart. (Shows led activity but no video output or network connection)

This likely means the the OS flashed on the SD card is incompatible with the bootloader on the eMMC. Can check the issue using a USB TTL debug cable.

@LucidScrubJay

Is there a way to force the card to only boot from emmc and just keep SD storage as such?

A dynamic workaround is to stop and change the boot sequence using a USB TTL cable:

Disable eMMC card while booting

AFAIK the boot order is set in SOC’s BootROM (SPI -> eMMC -> SD -> USB) and cannot be changed. I did some hacks in u-boot for Rock Pi 4 in Armbian to always try to boot from SD if it is present but first u-boot stage is still run from eMMC. If you can boot as far as u-boot proper from you eMMC you could stop autobooting - hit any key while in u-boot - somewhere around the Model: ... line. At the prompt you can then examine mmc/sd devices: => mmc list dwmmc@fe320000: 1 (SD) sdhci@fe330000: 0…

Another, static way to do it can be to edit the bootloader config on eMMC to boot from eMMC only. When you want to boot from SD, will need to remove eMMC.