Unable to boot from emmc after flashing it

[rfm83]

I have a working pbpro with a working emmc which I have flashed several times with different images. No issues until I incorrectly flashed it with an Arch image.
Now I'm unable to boot from it. When powering on the device, the power light stays solid amber with a black screen. No activity at all.
This happens with or without a bootable SD card inserted. 

However, I figured out that the machine boots from the SD card only if I disable the physical emmc switch on the inside. If I switch it back on during boot up or after the OS is already running from SD card, the emmc is not recognized at all. Does it mean I possibly bricked it? Is there any other workaround to try to make the emmc show up again after booting from the SD card?

I'm trying to get a hold of a emmc to USB adapter to see if it's readable on another device.

Has anyone experienced anything similar?

[KC9UDX]

Yes; I would say it's pretty easy to cause this to happen. No, you haven't bricked anything. Something in your boot is crashing, probably U-boot. Your eMMC is working, else the power lamp (which is controlled solely by software) would not light. If you can afford to wipe the eMMC and rewrite it from scratch, then simply do that. You'll have to disable it; boot from SD; and early in the boot process, re-enable the eMMC. I know there can be ways to enable the eMMC after booting, but I am not familiar with how to do it. If you get an eMMC to USB adaptor, you can just re-flash it with a working image that way.

[wdt]

From the wiki, emmc section

echo fe330000.mmc >/sys/bus/platform/drivers/sdhci-arasan/unbind
echo fe330000.mmc >/sys/bus/platform/drivers/sdhci-arasan/bind

(Note: with the device trees coming with older kernels (Linux < 5.11), the device name may be fe330000.sdhci instead of fe330000.mmc)

lsblk to see if it shows up
flipping the disable/enable switch (to enable) @ aprox 4 sec into boot
perhaps the command is easier, but you have to flip the switch anyway

[rfm83]

Thanks for replying guys. I was able to get the emmc to show up again by flipping the physical switch and enable it early on in the boot process. Now I can just reflash it again.