Looking for some help in getting this install booting. I picked up an nvme drive for my pinebook pro and decided to also use this as a chance to test out btrfs.
Distro: Manjaro
Hardware: Pinebook Pro
After reading some I decided to start with a more default set-up and learn from there. So I used an iso w/ default btrfs install. With the idea of flashing it to nvme (getting a nice stood up btrfs) and then moving files from emmc to nvme.
At the end of this process, I am stuck with a blank screen after boot loader (w/o ability to switch tty’s). I’ll try to walk through my process to identify what may help
Flashing img to nvme
Created img
sudo buildarmimg -d pbpro -e lxqt -b testing -p btrfs
Used Etcher to make bootable sd card and booted into live iso.
Used manjaro-arm-flasher to install to nvme.
Mounted nvme /boot and emmc /boot partitions
sudo mount /dev/nvme0n1p1 /mnt/tmp
sudo mount /dev/mmcblk2p1 /mnt/tmp2
Copied /boot/* from nvme0n1p1 to mmcbkl2p1
sudo rsync -avHAXS /mnt/tmp/ /mnt/tmp2
Edited extlinux.conf to reflect correct UUID of mmcblk2p1
Unmounted both /boot dir’s and mounted /home on nvme0n1p2
sudo mount -t btrfs -o subvol=@home,defaults /dev/nvme0n1p2 /dev/tmp
Edited /etc/fstab to reflect /boot on mmcblk2p1
Unmounted nvme completely and rebooted.
At this point I was able to boot and use lsblk to see everything was correct so far. /boot on emmc and /root on nvme. Feeling confident, I booted back into the live iso 
Moving old install to nvme
Used gparted to remove nvme0n1p1 and expand nvme0n1p2 to whole disk.
Mounted my new nvme fs
sudo mount -t btrfs -o subvol=@,defaults /dev/nvme0n1p2 /dev/tmpRoot
sudo mount -t btrfs -o subvol=@home,defaults /dev/nvme0n1p2 /dev/tmpRoot/home
sudo mount /dev/mmcblk2p1 /mnt/tmpRoot/boot
Mounted my old emmc fs
sudo mount /dev/mmcblk2p2 /mnt/tmp
Move correct fstab to avoid mistakes
sudo cp -a /mnt/tmpRoot/\@/etc/fstab /mnt/tmp/etc/fstab
Copy data from emmc to nvme
sudo rsync -avHAXS /mnt/tmp/ /mnt/tmpRoot/\@ --exclude={'boot','dev','home','mnt','proc','run','sys','tmp'}
sudo rsync -avHAXS /mnt/tmp/home/ez/ /mnt/tmpRoot/\@home/ez
JIC, chroot into nvme fs and update
sudo manjaro-chroot /mnt/tmpRoot /bin/bash
sudo pacman -Syyu
Exit chroot and rebooted to blank screen. No blinking cursor or ability to change to other tty. 
I chrooted back through the live iso and reinstalled the kernel, which ran mkinitcpio but, on reboot it had same effect.
sudo pacman -S linux
Second try chroot back into nvme fs, this time reinstalled uboot without any luck either.
sudo pacman -S uboot-pinebookpro
sudo dd if=/boot/idbloader.img of=/dev/mmcblk2 seek=64 conv=notrunc,fsync
sudo dd if=/boot/uboot.img of=/dev/mmcblk2 seek=16384 conv=notrunc,fsync
I know that’s quite the journey but, I can chroot in and update just fine so it shouldn’t be too far away…
lsblk/chroot/blkid/fstab/extlinux.conf ... output
[oem@manjaro-arm ~]$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
sda 8:0 1 14.5G 0 disk
|-sda1 8:1 1 213.6M 0 part /boot
`-sda2 8:2 1 14.2G 0 part /
mmcblk2 179:0 0 58.2G 0 disk
|-mmcblk2p1 179:1 0 213.6M 0 part
`-mmcblk2p2 179:2 0 58G 0 part
mmcblk2boot0 179:32 0 4M 1 disk
mmcblk2boot1 179:64 0 4M 1 disk
zram0 252:0 0 5.7G 0 disk [SWAP]
nvme0n1 259:0 0 238.5G 0 disk
`-nvme0n1p2 259:1 0 238.2G 0 part
[oem@manjaro-arm ~]$ sudo mount -t btrfs -o subvol=@,defaults /dev/nvme0n1p2 /mnt/tmpRoot/
[oem@manjaro-arm ~]$ sudo mount -t btrfs -o subvol=@home,defaults /dev/nvme0n1p2 /mnt/tmpRoot/home
[oem@manjaro-arm ~]$ sudo mount /dev/mmcblk2p1 /mnt/tmpRoot/boot/
[oem@manjaro-arm ~]$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
sda 8:0 1 14.5G 0 disk
|-sda1 8:1 1 213.6M 0 part /boot
`-sda2 8:2 1 14.2G 0 part /
mmcblk2 179:0 0 58.2G 0 disk
|-mmcblk2p1 179:1 0 213.6M 0 part /mnt/tmpRoot/boot
`-mmcblk2p2 179:2 0 58G 0 part
mmcblk2boot0 179:32 0 4M 1 disk
mmcblk2boot1 179:64 0 4M 1 disk
zram0 252:0 0 5.7G 0 disk [SWAP]
nvme0n1 259:0 0 238.5G 0 disk
`-nvme0n1p2 259:1 0 238.2G 0 part /mnt/tmpRoot/home
/mnt/tmpRoot
[oem@manjaro-arm ~]$ sudo manjaro-chroot /mnt/tmpRoot /bin/bash
[root@manjaro-arm /]# cat /boot/extlinux/extlinux.conf
LABEL Manjaro ARM
KERNEL /Image
FDT /dtbs/rockchip/rk3399-pinebook-pro.dtb
APPEND rootflags=subvol=@ initrd=/initramfs-linux.img console=ttyS2,1500000 root=PARTUUID=7b2e3695-1ad9-498d-b729-0d64f34150a1 rw rootwait quiet splash plymouth.ignore-serial-consoles
[root@manjaro-arm /]# cat /etc/fstab
# Static information about the filesystems.
# See fstab(5) for details.
# <file system> <dir> <type> <options> <dump> <pass>
PARTUUID=0c3b394c-c7da-4b06-86a6-aa2fe0db5f61 /boot vfat defaults 0 0
PARTUUID=7b2e3695-1ad9-498d-b729-0d64f34150a1 / btrfs subvol=@,compress=zstd,defaults,noatime 0 0
PARTUUID=7b2e3695-1ad9-498d-b729-0d64f34150a1 /home btrfs subvol=@home,compress=zstd,defaults,noatime 0 0
[root@manjaro-arm /]# sudo blkid
/dev/nvme0n1p2: LABEL="ROOT_MNJRO" UUID="a986a981-441a-41cd-b5ae-bd7c35d5c1c1" UUID_SUB="f882d0f9-4f2e-4c6c-b9ed-1d8055940760" BLOCK_SIZE="4096" TYPE="btrfs" PARTLABEL="primary" PARTUUID="7b2e3695-1ad9-498d-b729-0d64f34150a1"
/dev/mmcblk2p2: LABEL="ROOT_MNJRO_X" UUID="b6bfcf3e-3b70-413a-8021-870914aa76f2" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="primary" PARTUUID="a6791224-0ddc-43d3-83df-7cf3a4abf9b8"
/dev/mmcblk2p1: SEC_TYPE="msdos" LABEL_FATBOOT="BOOT_MNJRO" LABEL="BOOT_MNJRO" UUID="A59A-BDF9" BLOCK_SIZE="512" TYPE="vfat" PARTLABEL="primary" PARTUUID="0c3b394c-c7da-4b06-86a6-aa2fe0db5f61"
/dev/sda2: LABEL="ROOT_MNJRO" UUID="1b509f2a-2757-4afb-847c-768cad1091dd" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="primary" PARTUUID="fc5de836-8600-4753-870b-dfa59af1d21f"
/dev/sda1: SEC_TYPE="msdos" LABEL_FATBOOT="BOOT_MNJRO" LABEL="BOOT_MNJRO" UUID="EB96-8328" BLOCK_SIZE="512" TYPE="vfat" PARTLABEL="primary" PARTUUID="0dda2583-4800-450d-ae7b-45f5afb3f3fa"
/dev/zram0: LABEL="zram0" UUID="fda83a65-9868-45cd-87d4-63eb68c2e650" TYPE="swap"
[root@manjaro-arm /]# sudo pacman -Syyu
:: Synchronizing package databases...
core 242.4 KiB 182 KiB/s 00:01 [####################################################################] 100%
extra 2.4 MiB 803 KiB/s 00:03 [####################################################################] 100%
community 6.2 MiB 1670 KiB/s 00:04 [####################################################################] 100%
:: Starting full system upgrade...
there is nothing to do
I originally posted to the manjaro forum but, haven’t gotten any response after getting myself stuck.