Unfortunately we cannot get to a getty shell unless we also run:
setenv SWITCH_SEL 3
from the SBL shell. Furthermore, actually getting kernel output
requires setting console=ttySAC2,115200.
SWITCH_SEL might be related to the "MUIC" of the device, but the
variable also controls whether or not it is possible to get serial
output from pads on main board, and seems weird that those pads are
affected by MUIC (unless pads are also behind MUIC, but seems like
that would be very annoying when developing the device)
See also initial MR where mainline support for i9100 was added, where
serial output is also discussed:
https://gitlab.com/postmarketOS/pmaports/-/merge_requests/1598#how-to-get-serial-output
[ci:skip-build]: already built successfully in CI
7852e08148