Booting S905x4 (Transpeed X4) from EMMC failing due to avb2

Hello, I’ve got 4 other of these same Transpeed X4 S905x4/4gb ram/32gb emmc/100mbit boxes from aliexpress that have ce installed to emmc and worked fine but this latest one seems to be giving me fits. It boots stock android fine from emmc and with android on the emmc, it boots coreelec just fine from usb (toothpick trick). But once ce is installed to emmc, it will no longer boot.

I hooked up a serial connection to see what was going on and it seems to be failing to pass avb (see linked update.log below, around line 1342, for the actual error). Additionally, if I setenv avb2 0 from the console, I can successfully issue boot and it’ll boot coreelec off the emmc, but upon another reboot, it gets tossed into that boot loop failing avb again. It seems saveenv doesn’t do anything because my avb2 env property gets reset back to 1 every boot. I checked my other boxes and avb2 is enabled on them, so it seems weird that this one only boots with it disabled.

Logs (new user so I can’t attach, but I’ve linked logs):

  • android.log - this is just a log of it booting android. Hoping maybe a tidbit of info here could help
  • update.log - this takes us through a boot (initiated via a reboot update from android) to usb, a ceemmc -x command and successfull install to emmc, a reboot from there that fails avb, and then dropping into a console, disabling avb and successfully booting

Any thoughts here? I’ve restored android to this thing a few times, booted that up, and started over installing ce, but it always runs in to this boot loop with avb failing.

EDIT: I should note, I’m using CoreELEC-Amlogic-ne.arm-20.2-Nexus-Generic.img

You will need to add setenv avb 0 in cfgload script.
Or modify the bootfrom... var and add this before load cfgload script.
I am not sure anymore.

We will not add this as default as it disable L1 on Android boot

I wasn’t advocating setting that as a default, more so trying to figure out why this particular box needs it and my others don’t.

I think my last tests on another device did work with

setenv avb 0
setenv avb2 0

Just run then reset and check with printenv again.
If again on 1 something else set it in env

Interesting, this seemed to work for me.
setenv bootfromemmc "setenv avb2 0; run cfgloademmc"
followed by

saveenv does indeed work (noted by setenv avb 0 since avb was never a property but upon a reset it does exist in env and is set to 0). I saved the above in bootfromemmc and now it boots fine. Odd that that this box needs that but I guess at least I have a functioning box now. I plan to buy a few more of these so we’ll see how they go. Thanks for the help :wink:

At this place saveenv should not need at all.

1 Like

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.