after many tryings I thought of connecting other (more powerful) supply when the one dedicated for C2 didn't work nor any micro USB helped
I connected heavy supply to GPIO pins and this time it didn't hang when SD and eMMC were present at the same time
the board booted from SD and this time it was possible to make chroot
I don't see any logical explanation for this situation but it worked my old os C2 is alive 😸
Onira got a reaction from going in switched kernel meson64 to sunxi and it's not booting anymore