Boot with m2 with SD card

#1

Can anybody point me please

I format a m2 with the standard debian image
I format an SD card likewise
I boot and the SD card boots with nvme root

but I need gstreamer h264 and Debian is anal about software patents

I format the m2 with ubuntu (server) image
I format the SD with ubuntu
System boots SD root
I format SD with stock Debian image
I boot ubuntu with vnme root
There is no audio

I repeat 1 but can only get SD root !!!
I can mount /dev/nvme0n1p5 and see the FS
What/How do I get nvme root with standard debian install >

Just to check all is we I boot an ACER m2, previously prepared, without a SD card and it boots correctly.

I’m confused here, where is boot selection made, where does root expansion happen? I looked at systemd services but saw nothing obvious
Thanks
James

#2

OK the same question another way.
How do I get root on nvme:

rock@rockpi4b:~$ df -lh
Filesystem Size Used Avail Use% Mounted on
udev 961M 0 961M 0% /dev
tmpfs 193M 676K 192M 1% /run
/dev/mmcblk0p5 28G 2.0G 25G 8% /
tmpfs 964M 0 964M 0% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 964M 0 964M 0% /sys/fs/cgroup
tmpfs 193M 8.0K 193M 1% /run/user/1000
/dev/mmcblk0p4 511M 37M 475M 8% /boot
tmpfs 193M 0 193M 0% /run/user/109

rock@rockpi4b:~$ ls -l /dev/nv*
crw------- 1 root root 243, 0 Oct 6 16:48 /dev/nvme0
brw-rw---- 1 root disk 259, 0 Oct 6 16:48 /dev/nvme0n1
brw-rw---- 1 root disk 259, 1 Oct 6 16:48 /dev/nvme0n1p1
brw-rw---- 1 root disk 259, 2 Oct 6 16:48 /dev/nvme0n1p2
brw-rw---- 1 root disk 259, 3 Oct 6 16:48 /dev/nvme0n1p3
brw-rw---- 1 root disk 259, 4 Oct 6 16:48 /dev/nvme0n1p4
brw-rw---- 1 root disk 259, 5 Oct 6 16:48 /dev/nvme0n1p5

rock@rockpi4b:~$ cat /etc/os-release
PRETTY_NAME=“Debian GNU/Linux 10 (buster)”
NAME=“Debian GNU/Linux”
VERSION_ID=“10”
VERSION=“10 (buster)”
VERSION_CODENAME=buster
ID=debian
HOME_URL=“https://www.debian.org/”
SUPPORT_URL=“https://www.debian.org/support”
BUG_REPORT_URL=“https://bugs.debian.org/”

rock@rockpi4b:~$ uname -a
Linux rockpi4b 4.4.154-112-rockchip-gfdb18c8bab17 #1 SMP Thu Jan 21 04:50:13 UTC 2021 aarch64 GNU/Linux