Tow-boot problems and restoring uboot

[shulamy]

Based on the doc linked in post #4 I think zeroing 32k starting at an 8k offset should remove enough of the u-boot from the SD for the pinephone to boot from eMMC, but I haven't tried it. Something like this, assuming I've remembered which device is uSD and which eMMC - do check!
dd if=/dev/zero of=/dev/mmcblk0 bs=1024 seek=8 count=32

 i have tried it and it booted from emmc like it should

 but when i tried to tell tow-boot to boot from sd card the boot hanged

 so i think that dd command wipes too much of u-boot

 and it is for use the sd card as storage only

 ezik

multi-distro sd doesn't boot either when i tell it to boot feom emmc

and then tell tow-boot to boot from sd again

after the aqua led the phone vibrate three times with red led then yellow

and fall back to boot from emmc (manjaro phosh if it matters)

ezik

[wibble]

You'll need to be more specific about exactly what you're trying to do as the details may matter. We have 3 bootloaders with differing capabilities and requirements:
tow-boot - configuration is baked in, so it should 'just work' with standard partitioning from distros that use the specific layout it needs. It won't work with distros that don't follow the layout it needs, or more complicated partitioning and multibooting options.
u-boot - can be configured so can be made to work in some situations where tow-boot can't, but as it doesn't have display support there are practical limitations to using it for multi-option situations.
pboot - from Megous, with a gui - very versatile but rarely used beyond the multi-OS SD image, and you'll need to do the config yourself.

The reason for overwriting (part of) u-boot (or whatever other bootloader) on the SD is to make sure it won't work as a bootloader, otherwise the bootloader on the emmc won't be used. The bootloader on the emmc must be capable of booting whatever you have on the SD though.

[shulamy]

i have manjaro phosh on the emmc and i flashed tow-boot to it
  manjaro boots fine but when i swiched boot to sd with arch phosh (from dreemurrs -embeded) that i wiped it's boot loader
  and it didn't boot.  i flashed arch on this sd again with boot loader but i'll wipe it again and see what happens
 
  ezik

and i described what happens with milti-distro sd in #11

ezik

[shulamy]

dmes - dmesg from manjro boot on emmc

 dmesa  - dmesg from arch on sd rederected from tow-boot on emmc

  you can see it tries to load danctnix kernel  but at the end manjaro is booted

 ezik

[wibble]

I see you've asked at https://github.com/dreemurrs-embedded/Pi...issues/391 - posting here for anyone who's missed it.

[shulamy]

I see you've asked at https://github.com/dreemurrs-embedded/Pi...issues/391 - posting here for anyone who's missed it.

 i wanted to post here as well but file attachment refused to work

 maybe because i was on windows xp

 ezik