UPDATE: Looks like it's also applicable on Nokia 2.1 V by analyzing aboot. So previous NB1-Collision reserved as reference of EDL method, in case HMD may block it soon.
Please let me know if it doesn't work on your current firmware version. I'm working on make the overall procedure much more stable.
UPDATE: Looks like NB1-Collision is the only way to unlock the bootloader. Please read this topic to acquire the tool and attempt to unlock it: https://forum.xda-developers.com/sho...php?p=79825293
If Android 9 firmware installed, phone disassembly and wire trick required.
So we recommend users unlock the phone immediately once bought.
Following procedure is archived.
Step 1: Download firmware which consists the service bootloader file
You can download it from https://fih-firmware.hikaricalyx.com/hmd_en.html#e2m
Please download E2M-0390-0-00WW-B02 one in this case. If you're using Android 9, download E2M-108C-0-00WW-B01.
Then, extract E2M-0-0390-00WW-1-2-emmc_appsboot_service.zip to get service bootloader file, and the extract password is "WLBGFIH123".
Step 2: Boot your phone to Download mode (Fastboot mode)
You can execute following command then connect your phone when powered off, or use any other method you're familiar with:
fastboot oem alive
fastboot oem dm-verity (md5_of_serial_number)
For example, if your Serial Number is E2MGAHIKARICALYX, the md5 checksum is 0ab1b1e9f3aacc85849341cd5fb21412, then command will be:
fastboot oem dm-verity 0ab1b1e9f3aacc85849341cd5fb21412
And flash service bootloader:
fastboot flash aboot /path/to/E2M-0-0390-00WW-1-2-emmc_appsboot_service.mbn fastboot reboot-bootloader
Your phone will reboot to service bootloader. Then grant unlock permission with following commands:
fastboot oem dm-verity (md5_of_serial_number) fastboot oem fih on fastboot oem devlock allow_unlock
fastboot oem flashing unlock_critical
fastboot oem alive (wait for triggering to download mode) fastboot oem dm-verity (md5_of_serial_number) fastboot oem fih on fastboot oem devlock allow_unlock fastboot oem unlock-go
Then reboot your phone to Download mode again and restore deviceinfo:
That wraps up the overall unlock procedure.
In case HMD will block this method, you can use EDL method to downgrade aboot partition from this article: https://forum.xda-developers.com/nok...ader-t3938072/