[ROM][UNOFFICIAL] LineageOS 17.1 for Unihertz Atom L (20200828)

[landsome]

Last time few people asked me to describe rooting of my Atom L step by step. Here it is. The method is very similar to what is described in the top, but here a recovery for "Atom XL" is used instead of recovery for "Atom L" that didn't work when I've tried it. Now is it possible that last version of TWRP works, but I didn't try it.

1. Standard steps to provide control of the phone via adb: unlock bootloader, install adb anf fastboot on the computer, enable USB debugging, connect the phone to the computer, ensure that adb sees the phone.

2. Run `adb reboot bootloader` to put your device in bootloader mode

3. Run `fastboot flash --disable-verification --disable-verity vbmeta vbmeta.img`

4. Run `fastboot flash --disable-verification --disable-verity vbmeta_system vbmeta_system.img`

5. Run `fastboot flash --disable-verification --disable-verity vbmeta_vendor vbmeta_vendor.img`

6. Run `fastboot flash recovery "Recovery XL.img"` (this is a recovery of Atom XL)

7. Run `fastboot reboot`, after thet press volume+ button to enter recovery

8. Choose Apply Update, then Apply Update from ADB.

5. Run `adb sideload Magisk-v20.4.zip` from your PC

6. Wait for the process to finish. The recovery might prompt something about verification failure, just ignore it and continue anyway.

8. Reboot into system and enjoy.

Thanks a lot. No changes on the custom rom front, am I right?

 

[a-dead-trousers]

Last time few people asked me to describe rooting of my Atom L step by step. Here it is. The method is very similar to what is described in the top, but here a recovery for "Atom XL" is used instead of recovery for "Atom L" that didn't work when I've tried it. Now is it possible that last version of TWRP works, but I didn't try it.

Or you could do WITHOUT flashing my recovery (Atom XL) at all.

1. Install LATEST Magisk 22.0 apk.
2. Download the Official ROM from Unihertz and extract "boot.img".
3. Transfer "boot.img" onto your SD card (or whatever).
4. Use Magisk on your phone to install it into your "boot.img".
5. Transfer the modified "boot.img" (different name!) back onto your computer.
5. Boot your phone into bootloader and use "fastboot flash boot boot.img" to flash the magisk mdified "boot.img".
6. Profit!

EDIT2: EDIT: No need for vbmeta & co. Obviously the steps for vbmeta to disable AVB are needed nonetheless.
(see my post further down)

 

[a-dead-trousers]

Thanks a lot. No changes on the custom rom front, am I right?

See my PM.

 

[covexx]

See my PM.

Or you could do WITHOUT flashing my recovery (Atom XL) at all.

1. Install LATEST Magisk 22.0 apk.
2. Download the Official ROM from Unihertz and extract "boot.img".
3. Transfer "boot.img" onto your SD card (or whatever).
4. Use Magisk on your phone to install it into your "boot.img".
5. Transfer the modified "boot.img" (different name!) back onto your computer.
5. Boot your phone into bootloader and use "fastboot flash boot boot.img" to flash the magisk mdified "boot.img".
6. Profit!

EDIT: No need for vbmeta & co.

There are few more steps to do

0. switch on developer mode, switch on oem unlocking, adb reboot bootloader, fastboot flashing unlock - othewise it is not possible to flash anything.

In the step 5. I would recommend to test the modified boot.img with just fasbtoot boot boot.img (this boots it one time) - I did that but I overlooked that the device rebooted after that back to original bootloader and I thought it is OK, but it was not.

After flashing the boot.img from magisk I ended up in an infinite bootloader loop - it start the bootloader up to message the device is not trusted (unlocked), it will boot in 5s but it then reboots.

I had to take the device apart (two layers of terrible design to get to battery contact) to disconnect the battery, but still no go - holding the Pwr and VolDwn button does not react. I thought I'll try the SP flash tool for MTK, but my only Windows 7 are not in the best shape, not sure the provided drivers from Uniherzt really do work.

So now obvious question - what to try next to resurect the phone?

 

[covexx]

There are few more steps to do

0. switch on developer mode, switch on oem unlocking, adb reboot bootloader, fastboot flashing unlock - othewise it is not possible to flash anything.

In the step 5. I would recommend to test the modified boot.img with just fasbtoot boot boot.img (this boots it one time) - I did that but I overlooked that the device rebooted after that back to original bootloader and I thought it is OK, but it was not.

After flashing the boot.img from magisk I ended up in an infinite bootloader loop - it start the bootloader up to message the device is not trusted (unlocked), it will boot in 5s but it then reboots.

I had to take the device apart (two layers of terrible design to get to battery contact) to disconnect the battery, but still no go - holding the Pwr and VolDwn button does not react. I thought I'll try the SP flash tool for MTK, but my only Windows 7 are not in the best shape, not sure the provided drivers from Uniherzt really do work.

So now obvious question - what to try next to resurect the phone?

I managed to bring it back to life with the SPMultiportFlashDownloadProject.exe provided by Unihertz (under Windows).

 

[covexx]

Tried to repeat the boot.img patching with magisk after I reflashed AtomL with the provided EU image, it boots with just fastboot boot boot.img but no root, if flashed the phone is in bootloop again. There are two differences 1. I use the AtomL EU image 2020110320_g63v71c2k_dfl_eea.zip, and 2. I use the latest Magist 23.

Sadly this simple method is not working for this configuration.

 

[a-dead-trousers]

Tried to repeat the boot.img patching with magisk after I reflashed AtomL with the provided EU image, it boots with just fastboot boot boot.img but no root, if flashed the phone is in bootloop again. There are two differences 1. I use the AtomL EU image 2020110320_g63v71c2k_dfl_eea.zip, and 2. I use the latest Magist 23.

Sadly this simple method is not working for this configuration.

That's odd...

0. switch on developer mode, switch on oem unlocking, adb reboot bootloader, fastboot flashing unlock - othewise it is not possible to flash anything.

Thanks.
I didn't mention that because you also need to do that when you are using TWRP (beforehand).

I had to take the device apart (two layers of terrible design to get to battery contact) to disconnect the battery, but still no go - holding the Pwr and VolDwn button does not react. I thought I'll try the SP flash tool for MTK, but my only Windows 7 are not in the best shape, not sure the provided drivers from Uniherzt really do work.

Whoa... Glad I didn't had to go through this for all the times I nearly bricked my device. I was always able to use spflash to get out of the bootloop by simply flashing a corrected partition img (boot or recovery) or in some totally ****ed up situations the whole stock rom.

@ Everyone
I really recommend to try at least one stock rom flash with spflash before getting anything done custom rom wise. That way you can be sure that you are always able to revert what you did without the need to disassemble the phone.

 

[a-dead-trousers]

Tried to repeat the boot.img patching with magisk after I reflashed AtomL with the provided EU image, it boots with just fastboot boot boot.img but no root, if flashed the phone is in bootloop again. There are two differences 1. I use the AtomL EU image 2020110320_g63v71c2k_dfl_eea.zip, and 2. I use the latest Magist 23.

Sadly this simple method is not working for this configuration.

I think I know the reason now:
AVB is active by default. So maybe that's why you cannot boot into system.
If you are still willing to test this you could try to

fastboot flash --disable-verification --disable-verity vbmeta vbmeta.img
fastboot flash --disable-verification --disable-verity vbmeta_system vbmeta_system.img
fastboot flash --disable-verification --disable-verity vbmeta_vendor vbmeta_vendor.img

If that helps your problem is definitly AVB related. AFAIK magisk should have an option to handle this but I'm not sure how well it has been tested with the latest big overhaul (v20 > v21). Maybe you can ask in the magisk support threads if there is a better solution than to disable AVB completly to get arround this.

 

[covexx]

Whoa... Glad I didn't had to go through this for all the times I nearly bricked my device. I was always able to use spflash to get out of the bootloop by simply flashing a corrected partition img (boot or recovery) or in some totally ****ed up situations the whole stock rom.

After all, it was not necessary, I was hoping that after battery disconnection, I can enter the recovery via power and volume button, but it did not work. After I made a Windows MTK driver working, I was able to get from the boot loop just via SPflash tool. So yes I agree - before any manipulation with boot.img everybody should make sure that SPflash is working for them.

 

[covexx]

After all, it was not necessary, I was hoping that after battery disconnection, I can enter the recovery via power and volume button, but it did not work. After I made a Windows MTK driver working, I was able to get from the boot loop just via SPflash tool. So yes I agree - before any manipulation with boot.img everybody should make sure that SPflash is working for them.

I think I know the reason now:
AVB is active by default. So maybe that's why you cannot boot into system.
If you are still willing to test this you could try to

fastboot flash --disable-verification --disable-verity vbmeta vbmeta.img
fastboot flash --disable-verification --disable-verity vbmeta_system vbmeta_system.img
fastboot flash --disable-verification --disable-verity vbmeta_vendor vbmeta_vendor.img

If that helps your problem is definitly AVB related. AFAIK magisk should have an option to handle this but I'm not sure how well it has been tested with the latest big overhaul (v20 > v21). Maybe you can ask in the magisk support threads if there is a better solution than to disable AVB completly to get arround this.

RIght, so after this tripplet, the boot with magisk modified boot.img works and root is working. Great.

 

[covexx]

To sum it up:
0a. Reflash phone with the original Uniherzt image from their google disk https://drive.google.com/drive/folders/0By1nhWOmuw2KdDhTUlFOZHpXQjg
using their SPflash tool (works under Windows (on Linux you may try Wine), the MTK driver needs to be properly installed and phone detected in device manager - everyting is on Unihertz gdrive)
- 2020110320_g63v71c2k_dfl_eea.zip at that time for EU AtomL
The SPflash tool is not very intuitive, generally it is enought to pres Scan and wait until it detects the phone (phone reboot needed), then press "Start all".

This way you'll make sure you can get phone from any bricked state, also the phone software will be at known version and clean.

0b. On the phone switch on developer mode, switch on oem unlocking, adb reboot bootloader, fastboot flashing unlock - othewise it is not possible to flash anything. (now the message the phone is not trusted starts to appear).

1. Install LATEST Magisk 23.0 apk on the phone (https://github.com/topjohnwu/Magisk)
2. Extract "boot.img" from Unihertz image
3. Transfer "boot.img" onto your SD card (or whatever - adb push, mtp).
4. Use Magisk on your phone to install it into your "boot.img" (see magisk github doc)
5. Transfer the modified "boot.img" (different name! magisk_patched*.img) back onto your computer.
6. Boot your phone into bootloader - adb reboot bootloader
7. Disable vmbeta verification:
fastboot flash --disable-verification --disable-verity vbmeta vbmeta.img
fastboot flash --disable-verification --disable-verity vbmeta_system vbmeta_system.img
fastboot flash --disable-verification --disable-verity vbmeta_vendor vbmeta_vendor.img
8. "fastboot flash boot boot.img" to flash the magisk modified "boot.img".
fastboot reboot
9. Open Magisk, you should see it is installed (not only in ramdisk) and there is a menu for superuser capabilities.
10. adb shell; su -; allow

 

[a-dead-trousers]

0a. Reflash phone with the original Uniherzt image from their google disk https://drive.google.com/drive/folders/0By1nhWOmuw2KdDhTUlFOZHpXQjg
using their SPflash tool (works under Windows (on Linux you may try Wine), the MTK driver needs to be properly installed and phone detected in device manager - everyting is on Unihertz gdrive)
- 2020110320_g63v71c2k_dfl_eea.zip at that time for EU AtomL
The SPflash tool is not very intuitive, generally it is enought to pres Scan and wait until it detects the phone (phone reboot needed), then press "Start all".

I made an updated how-to for spflash (with latest version & drivers)

android_device_Unihertz_Atom_LXL/docs/HOW-TO-FLASH-STOCK.md at master · ADeadTrousers/android_device_Unihertz_Atom_LXL

Common device tree for the Unihertz Atom L and XL - ADeadTrousers/android_device_Unihertz_Atom_LXL

github.com

 

[covexx]

Today Unihertz anounced a new OTA update for Atom L|XL. OTA (of course) fails on rooted device. There is no archive available yet on their google disk. It seems Atom (X)L does not have a A/B partitioning, so we can not get the OTA to work... am I right?

 

[a-dead-trousers]

Today Unihertz anounced a new OTA update for Atom L|XL. OTA (of course) fails on rooted device. There is no archive available yet on their google disk. It seems Atom (X)L does not have a A/B partitioning, so we can not get the OTA to work... am I right?

At least not rooted
You'd need to do spflash of previous ROM release to revert the root. Setup the phone once more and then run the ota update. There should be a way to extract boot.img from an unrooted device. Just search the net for it. Otherwise you'd need to wait for the google drive release to get root back again.

 

[it_unihertz_when_i_pee]

@a-dead-trousers

I didn't mean to ghost you. I found myself in the position of having some major life changes and wasn't really in a spot where I could afford to experiment with my phone and possibly be without it for some days. Now that the dust has settled, I'm coming back around to this project. Primarily because...

The LineageOS ROM from the OP doesn't allow me to get LTE service from my new provider (the stock ROM *does*, so I know the phone is capable). So I wanted to try a newer version...

I tried following the build guides you posted/PMed to me, with no success. My Linux skills are good but I have no experience with resolving ninja errors and the like. I might try to set up a dedicated Ubuntu VM for a build env, so I can do more copy-pasting and less thinking, but I'll need to chase down a terabyte-sized hard drive for the process.

In the mean time I thought to myself a rooted stock rom is probably good enough for now. I'd have LTE service and I can use root to force all of the Google-ware off the phone. However...

@GameHunter1

If I follow your steps with the 2020-11 stock image from Unihertz, it works. However, I can't apply the OTA update when rooted (as others have stated), and if I apply the OTA update before trying to root, the phone never boots into recovery to do the sideload. So there's a disconnect somewhere in that process, but that's as far as I've gotten.

 

[a-dead-trousers]

@GameHunter1

If I follow your steps with the 2020-11 stock image from Unihertz, it works. However, I can't apply the OTA update when rooted (as others have stated), and if I apply the OTA update before trying to root, the phone never boots into recovery to do the sideload. So there's a disconnect somewhere in that process, but that's as far as I've gotten.

Do you use me recovery for the sideload?
If yes the problem is that I've set up decryption support and that's probably not gonna work with the 2021-05 update as I integrated the 2020-11 vendor binaries.

 

[it_unihertz_when_i_pee]

Do you use me recovery for the sideload?
If yes the problem is that I've set up decryption support and that's probably not gonna work with the 2021-05 update as I integrated the 2020-11 vendor binaries.

Yes.

I got a working Lineage installed with your instructions here:

https://xdaforums.com/t/rom-10-0-un...hertz-atom-l-and-xl-alpha-2021-05-10.4171407/

Drunk-me wasn't bright enough to find that thread last night, but I was able to get it running this morning.

I did encounter a new problem though that is not only unique but fairly interesting. I'll post about it there, since I'm using that ROM.

 

[covexx]

I am still using this "May" image on Atom L. just found out that if secondary user sets up the Alarm (Clock) then the alarm starts only if set a few minutes in the future. After that the alarm just does not start (the clock app is probably put asleep). As an Owner the alarm works as expected. I set the clock app for both users as not battery optimized, behaves the same. Is there any known workaround, know android "feature", or maybe a fix in newer builds (https://xdaforums.com/t/rom-10-0-un...om-l-and-xl-alpha-2021-11-14.4171407/page-9)? Thanks

 

[a-dead-trousers]

I am still using this "May" image on Atom L. just found out that if secondary user sets up the Alarm (Clock) then the alarm starts only if set a few minutes in the future. After that the alarm just does not start (the clock app is probably put asleep). As an Owner the alarm works as expected. I set the clock app for both users as not battery optimized, behaves the same. Is there any known workaround, know android "feature", or maybe a fix in newer builds (https://xdaforums.com/t/rom-10-0-un...om-l-and-xl-alpha-2021-11-14.4171407/page-9)? Thanks

With "May" image you mean stock ROM or (my) LOS ROM?
(The LOS ROM by PeterCxy never had a May release)

 

[covexx]

With "May" image you mean stock ROM or (my) LOS ROM?
(The LOS ROM by PeterCxy never had a May release)

Sorry for missunderstanding, I am already lost in all my experimets. ATM I am using a stock image, just rooted.