I've been unable to install LibreELEC for RK3399 onto NanoPC T4 eMMC for a while now. I've tried with FriendlyCore Bionic and Armbian Buster installed onto eMMC.
This is script output from "LibreELEC-ARM-ALL.arm-9.80-devel-20200414164234-7071836-rk3399" build:
LibreELEC:~ # /flash/install2emmc.sh
12+0 records in
12+0 records out
12582912 bytes (12.0MB) copied, 0.086248 seconds, 139.1MB/s
1+0 records in
1+0 records out
512 bytes (512B) copied, 0.001853 seconds, 269.8KB/s
442+0 records in
442+0 records out
442 bytes (442B) copied, 0.001904 seconds, 226.7KB/s
24575+0 records in
24575+0 records out
12582400 bytes (12.0MB) copied, 0.085721 seconds, 140.0MB/s
Error: The location 16M is outside of the device /dev/mmcblk1mmcblk2.
Error: The location 533M is outside of the device /dev/mmcblk1mmcblk2.
8192+0 records in
8192+0 records out
4194304 bytes (4.0MB) copied, 0.037561 seconds, 106.5MB/s
mkfs.fat 4.1 (2017-01-24)
mkfs.vfat: unable to open /dev/mmcblk1mmcblk2p1: No such file or directory
mount: mounting /dev/mmcblk1mmcblk2p1 on /tmp/system failed: No such file or directory
No /dev/mmcblk1mmcblk2 partiton.