yashsingh1/xdaforums huggingface dataset:
[OnePlus Nord 2 5G] ezdiy:
The way boot works is:

BROM->preloader.bin(checks if vol-down, if so, jump back to BROM EDL routine). otherwise proceed with preloader vcom, LK etc. The secondary way to enter BROM is simply there being no preloader.bin to run, and BROM initiates its EDL command mode immediately, instead of preloader jumping back to it from later on.

The vol-down check (as well as others debugging stuff, like HW UART via USB) that lies in preloader is gated by efuse during manufacture (if you search ALPS9 tree for xml files, you'll find a list of whats in there).

So what if you want to disable the vol-down access as an OTA update? That's right, you tack a module on lk.bin to burn the efuse (which seems to be heavily implied by the string). The question is under which circumstances, if at all, this routine triggers in lk.bin (the bootable parts of OTA seems to be for bunch along with Nord, think stuff like Oppo Reno 5Z).

As for how these diffs were made, it's just strings & diff from unpacked ota zip vs lk.bin directly read from the device. But this is perhaps straying too technical to mtkclient low level details. PM me if you want to lurk relevant tg group where people deal with stuff more at length on various mtk hw.

I simply omit preloader.bin and lk.bin while flashing the OTA that looks sus like this. Either it works fine, or you get a bootloop (in which case you decide, whether you restore backup, or try your luck by completing the update by flashing preloader *AND* lk.bin - Never ever flash disperate versions of preloader & lk separately. Keep either both old, or both new. Version mismatch *between* those two is frequent source of bricks.

EDIT: Whatever applies for lk.bin applies for tee.bin that sits along with it, ie there's technically three-way version dependency between preload-lk-tee images you should keep. Other gotchas like repartitioning, seccfg and whatnot apply too, discussed elsewhere in here I think.
[OnePlus Nord 2 5G] Coconut_cube:
Quick update. According to this video, looks like the BROM EDL/Vol key check only gets disabled in C.05 and C.06 (at least for the Indian market). You seem to be able to regain functionality by rolling back to Android 11. I assume the preloader got updated in order to include the efuse check, which would explain why rolling back fixes it, as the preloader gets downgraded. Either that or the efuse wasn't permanent to begin with. Feel free to correct me if I'm wrong. Also, I'm pretty sure the device in the video had an unlocked bootloader so I don't know if that would affect things.
[OnePlus Nord 2 5G] user83919:
Same question here. Could we get an update for A.21?
[OnePlus Nord 2 5G] Kollin:
Both BROM and fastboot work on 05 for me.
[OnePlus Nord 2 5G] ezdiy:
Yep, Xiaomi did the same thing too - downgrading preloader restored BROM key, so the efuse check is most likely added in updated version of preloader.bin. This implies that for as long rollback is possible (without BROM!), you're fine.

From the looks of it, the whole thing seems designed for OTA update on locked bootloader where rollbacks *shouldn't* be possible (ie fastboot flash and spflash both refusing to flash older scatter).
[OnePlus Nord 2 5G] Coconut_cube:
How did you update exactly? Was everything stock beforehand?
[OnePlus Nord 2 5G] Kollin:
2103 A20 - 2101 C4 - 2101 C5
[OnePlus Nord 2 5G] FakeNewBoy:
is it normal for it to take a long time to load?
[OnePlus Nord 2 5G] pankspoo:
Anyone has oos c06,06 or C08 update zip or full partation backup ( i tried to take mtk client back of C05 but mtk client not working)
[OnePlus Nord 2 5G] suly77130:
hello i am bricked no matter what i have this error:

Preloader

Preloader - [LIB]: ←[31mStatus: Handshake failed, retrying...←[0m
[OnePlus Nord 2 5G] FakeNewBoy:
try to bypass with this utility
[OnePlus Nord 2 5G] jollran2005:
Will this work to downgrade from a.21 to a.20?
[OnePlus Nord 2 5G] roldev:
Yes.
[OnePlus Nord 2 5G] jollran2005:
Thanks for the reply, so after I unlocked bootloader, do I need mtkclient? or is "Flash Stock firmware with UNLOCKED bootloader" guide to downgrade without the use of mtkclient?
[OnePlus Nord 2 5G] roldev:
For some reason my attempt to recover through PartitionBackupper wasn't successful. Got some permission error.

Using locally installed mtk client under windows works fine.

I am on A20 now until change to custom stable ROM ( pixel experience, lineage os or leeos)

Cheers.
[OnePlus Nord 2 5G] jollran2005:
Thanks I'll try mtkclient tomorrow, do I need unlocked bootloader for mtkclient?
[OnePlus Nord 2 5G] roldev:
Sorry, cannot answer now. I was unlocked since the 1st day. Maybe in this large thread there is tip.

Luck.
[OnePlus Nord 2 5G] radnetro:
Can anybody help me? I can't seem to connect to mtk_gui
[OnePlus Nord 2 5G] roldev:
Which version you are on? BROM was disabled from C.04 or something ....

For sure C.01 eu has it and the last C.10 hasn't.
[OnePlus Nord 2 5G] DPJulien:
for the moment impossible to install any custom rom, I so regret having updated to C10. If anyone finds a workaround i'd gladly take it
[OnePlus Nord 2 5G] jollran2005:
Downgrade to android 11, you'll lose data when you flash custom rom anyways!
[OnePlus Nord 2 5G] DPJulien:
No :'( cause cannot access bootloader nor BROM. So no way to unlock bootloader, no way to install twrp, not even rollback cause the only way is through mtk client (BROM)
[OnePlus Nord 2 5G] jollran2005:
Rollback with rollback package from oneplus https://community.oneplus.com/wap/thread?id=1596759

It works for c 10
[OnePlus Nord 2 5G] roldev:
Great news for all, ended with c.10.

From A11 one can go for Pixel experience, elixir, leos or good old lineage :)
[OnePlus Nord 2 5G] Anteino:
I am using the re_livedvdV3.iso image because I cannot get the drivers to work on my PC. However, for writing, the program only takes .bin files. But I only have .img files. Any tips on how to get around this?
[OnePlus Nord 2 5G] roldev:
Make sure the files are correct ones.

Then rename IMG to BIN.

Both extensions means binary file with " some " content.
[OnePlus Nord 2 5G] Anteino:
Ahhh I see, it's as simple as renaming the files. Will definately try this, thanks!

EDIT: can confirm this works. Thank you!
[OnePlus Nord 2 5G] bigcool1337:
If I do this North 2 DN2103

A.20 install I can no longer update it it downloads but after restarting there is an error. with North 2 DN2103

A.15 also the same

i want to go back to stock. what can i do to update it to a12 or a13
[OnePlus Nord 2 5G] ScoutLord564:
i did all the steps my phone booted and its working but the network and the fingerprint isnt working
[OnePlus Nord 2 5G] Dounial:
Stupid question - I'm totally new with custom-roms and deeper phone-technology in general; I'm having a OnePlus Nord 2 5G I don't need which currently runs a really unstable version of Ubuntu Touch and I wanted to install OxygenOS on it instead of Ubuntu Touch - Is it possible to flash the OxygenOS on the phone from Ubuntu Touch - or has anyone experience with this and/or can help me? My main PC is running Linux (Arch, EndeavourOS - KDE/Plasma) and I only have access to windows via a virtual machine, my macbook just died the other day so macintosh is not an option for flashing, just Linux and if there is no other way around windows 10 (via VM like I said). Would be awesome if someone could help me a bit as I'm a custom-rom noob currently lol.
[OnePlus Nord 2 5G] Oswald Boelcke:
@jollran2005 I've delete the post that you created today at 06:50 UTC. Same applies to the post you made here. And from this post I've removed the link to Telegram.

Regarding social media links please observe that as an exemption from the last bullet of rule no. 5 of the XDA Forum Rules, we grant only developers the privilege to share references to their social media in their own development threads and if thorough support is provided in the thread. These conditions obviously don't apply to you, your threads or posts. Additional information is also available here:

Telegram Chat Channels - Way Forward

WhatsApp/Telegram Groups and Channels - Going Forward Hello XDA family! Just notifying all members that posting certain links to Telegram and other sites like WhatsApp is now allowed on XDA. What does that mean? We will allow links to messages...

xdaforums.com

Please refrain from pushing XDA users to Telegram or sharing links to social media on XDA unless done in your own development threads.

Thanks for your cooperation.

Regards

Oswald Boelcke

Senior Moderator
[OnePlus Nord 2 5G] jollran2005:
Sorry didn't realize it was against the rules, won't happen again
[OnePlus Nord 2 5G] Irfy84:
@Raygen: God bless in 2024.

With your A20 dump, I was able to unbrick my Nord2 that went into a bootloop after an unwanted System Update was accidentally triggered while on A17 and 1% battery. Couldn't quite get the userdata to restore, so it's wiped, but that's still much better than a brick.

I went with the mtkclient method of applying all images from the A20 zip file, had to wipe/format the data from stock recovery and it worked.

To further update the phone beyond A20, as always with this phone, I had to make sure that vbmeta, boot and recovery are stock, and then I was able to update to C10, then C14 so far (am aware of brom mode issue), phone feels 100% stock.

It's actually infuriating this phone never got full official images for manual flashing from OnePlus.
[OnePlus Nord 2 5G] pankspoo:
That's my question 🤣
[OnePlus Nord 2 5G] Raygen:
This rom does not overwrite userdata. But I highly suggest to do a backup first anyway.

The most straight forward fix you could try before re-flashing the whole rom though, is to flash back the stock recovery and do a full factory reset (

format

data) from there.

It's a live USB, a whole OS running from a pendrive (or in a virtual machine if you prefer). You do not use it in windows.

This firmware is for A.12 EU only, I'm not able to confirm any compatibility with A.13.
[OnePlus Nord 2 5G] pankspoo:
So we have its which OS actually? And we have to boot that USB via bios and then run the commands directly in cmd do. From. Which folder we need to. Run. Commnads
[OnePlus Nord 2 5G] Elaba:
Thanks, your stuff worked. Altough during flashing with the PartitionsBackupper, i noticed a few things failed because the partitions didn't exist. The phone boots again, not sure if that will affect the use with the missing files.

Still not sure what i did wrong to get stuck in a bootloop. I was able to unlock the bootloader and install twrp on my DN2103, did a nandroid backup (as the root tutor suggested) (never did a full whipe / data or cashe etc) , but after that i was not able to boot into the system anymore. Little bit scared to try the rooting process allover again. Any tips/ ideas what went wrong?

Side note: i had difficultees to enter fastboot on the phone (advanced reboot option is not available on my device in developer options), so i used this : https://androidfilehost.com/?fid=2188818919693784074 to reboot into fastboot.

Also: I'm not a total newb into rooting devices, done it before with other oneplus devices, but this tome something went wrong.
[OnePlus Nord 2 5G] TheWing:
I am having the exact same issue after restoring (I also had unlocked bootloader before and fastboot says it is locked now). Did you manage to fix it after following the locked bootloader instructions?
[OnePlus Nord 2 5G] pankspoo:
So I got successful to flash your given seccfg.img.

Then I booted in. Fastboot mode so tried try unlock bootloader commands to. Check and it's saying not allowed.

Means its still locked i think
[OnePlus Nord 2 5G] martinwildi:
i could also flash seccfg.img. But also still locked bootloader.

will try again later this week.

Here's a little more detailed instruction (@Raygen you can take this to your instructions, if you want):
[OnePlus Nord 2 5G] kkdamion:
before i run the the included .bat file i had twrp an unlocked BL, half wag the proces i started to notice errors like "failed can not flash bc of locked state errors" so my BL is locked and the command "fastboot flashing unlock" does not work anymore it just tells me "unlock failed"
[OnePlus Nord 2 5G] pankspoo:
I done all The things also python shown falshing completed still bootloader is showing locked i dont understand what's happening
[OnePlus Nord 2 5G] pankspoo:
So this is falshing on seccfg still no luck still its saying not allow bootloader locked
[OnePlus Nord 2 5G] Raygen:
I'll add a log generator in the next version of the tool so it can be seen what went wrong.

So far the best I can advise is to

format

data with the stock recovery before trying a second time (backup your data before that ofc)

Alright we're at 3 users to whom the bootloader got locked.

I'll reupload the .zip with the seccfg.img partition removed to avoid further harm for now, looks like it's another trouble making partition.

Strange that the firmware in @sakarya1980 's thread does include it without issues. I've tagged him to see if he can help us about this.

And we have 2 users to whom the bootloader unlock method doesn't work. I'll try to look into that, but for now it's the only method I'm aware of.

I see you've tried to flash the seccfg with a .tiff extension. Why's that?
[OnePlus Nord 2 5G] pankspoo:
I

I alredy flashed img also from Indiaan stock unlocked version and your also after changing name no luck
[OnePlus Nord 2 5G] TheWing:
I also tried the bootloader unlock method (after the broken boot/recovery message) and got the same result, fastboot saying it was still locked. After i messed with mtkclient flashing some images again or trying the proper mtkclient unlock method (from their github page) but no luck.

I managed to fix it today flashing with mtkclient the stock boot, recovery and vbmeta images from latest A12 ota, getting into the recovery and wiping all data, and after that the phone was finally working, and I could unlock the bootloader again and flash magisk and so.
[OnePlus Nord 2 5G] pankspoo:
Can you tell. Me how did you flashed boot and recovery using mtk client process
[OnePlus Nord 2 5G] TheWing:
python mtk w boot path/to/boot.img

python mtk w recovery path/to/recovery.img

Obviously replace the path with the proper one according where do you have those images
[OnePlus Nord 2 5G] pankspoo:
Did its not gave error of bootloader locked
[OnePlus Nord 2 5G] TheWing:
You can flash those even with the bootloader locked if you do it with mtkclient. Afterwards, with the phone able to boot properly, I unlocked the bootloader via fastboot again, since with mtkclient was a no go for me.
[OnePlus Nord 2 5G] pankspoo:
I flashed all files still its showing boot image corrupt
[OnePlus Nord 2 5G] Raygen:
Try to flaah just vbmeta from the latest ota (available here: https://mega.nz/folder/rQhhHQpA#nNHvPlmzBXwPjmaFpuDa2Q ) always through mtkclient
[OnePlus Nord 2 5G] pankspoo:
I am using A13 for all updates vbmeta is same i think I flashed vbmeta from twrp. Thread it's same i think
[OnePlus Nord 2 5G] jis251:
HI. My System was "gone". I couldn't do anything. From Stock recovery I couldn't Update online, no network found (wifi). Fastboot told that my bootloader is locked, even I had unlocked it. Stock recovery just came by itself, I didn't restore it. I took my phone to service and they were puzzled what had happened to my phone. I guess they will give me new one. Perhaps hardware is somehow broken. Their best guess was that.

Thanks your advices. I wait service to reply.
[OnePlus Nord 2 5G] TheWing:
Flash vbmeta again from the ota zip from A13 in your case. Before I reflashed vbmeta with mtkclient I also got the same message.
[OnePlus Nord 2 5G] pankspoo:
Someone give me A13 stock boot. Img, recovery I have vbmeta
[OnePlus Nord 2 5G] pankspoo:
O my god o my god u all are genuius thanks your help and our alls hardwork finally i cracked booted I can't believe 😂😭😜🤣😁

This will be new innovation for nord 2😊
[OnePlus Nord 2 5G] Raygen:
didn't you posted it in your thread? https://xdaforums.com/t/ota-update-process-for-rooted-nord-2-any-incremental-update.4347813/
[OnePlus Nord 2 5G] Elaba:
Today did a 2nd attempt to unlock the bootloader and instal Twrp. So far so good, haven't used the phone yet (pac-man edition) , Hopefully all goes well this time. I remember it probably went wrong the first time after i made a nand backup just after the rooting process . Haven't done a nand backup yet, bit scared to end up the same like before.
[OnePlus Nord 2 5G] Zombnombs:
Exact same boat for me as well. The included .bat seemed to work just fine, and then the phone no longer boots and gives the same error. Flashing unlock lets me press the volume up button to select "yes" but errors out, not allowed.

Whilst running the restore option in the .bat I noticed the first half worked flawless, but about halfway through it started running into the "not allowed in locked state" errors, so my theory is that the tool flashes in a LOCKED bootloader about midway through, thus practically interupting itself and half of partitions afterwards cannot be flashed.

Same issue as above here. So for some reason, a locked bootloader got flashed in? Not too sure why but it seems to be happening to multiple people.

Edit:

Okay so, I just followed the "for locked bootloader" steps

Successfully flashed the seccfg.img in the download link to the phone - But the bootloader is still locked.

After connecting back to my windows PC, the "fastboot flashing unlock" command still returns "operation not allowed" and trying to flash files still returns "FAILED (remote: 'not allowed in locked state')

The fastboot command "fastboot getvar all" returns message the message "(bootloader) unlocked: no"

So the bootloader is definitely still locked.

Isn't the most obvious answer to this whole situation (of several people having the same issue), is that the seccfg provided in the OP might be for a locked bootloader? So maybe a good samaritan somewhere with an unlocked bootloader can upload their seccfg, and we can check? Or maybe @Raygen can try reuploading it again? Always good to get a 2nd source so we can eliminate the possibility.
[OnePlus Nord 2 5G] Zombnombs:
After hours and hours of tinkering, I've not quite fixed the issue, but gotten the phone into a... slightly better state?

Phone now boots to (some kind of stock) recovery, and when trying to boot to system, phone gets stuck in a very short bootloop; Oneplus symbol appears, dispppears, repeats. Not your normal bootloop (which usually looks like 2 white dots spinning around larger red dot and takes longer before it reboots).

Using this stock recovery (which shows Ver1.2 at the bottom)'s Wipe data/Format Data functions do not seem to help at all. Curiously, the language menu on this stock recovery seems to be very different to the stock recovery that came with my phone; The otrder of the languages is different, and it has an extra "online update" option that I've never seen before. Otherwise it's practically the same.

This stock recovery also always prompts some kind of error like saying something along the lines of 'Kindly reminder, please connect inernet to update'. With pretty broken english and a few typo's in the popup. The "update system" button in the recovery doesn't work, as it can't find or access any wifi.

I'm wondering if I'm getting close to a fix here. I can explain steps taken to get here incase it helps others, and if anyone has seen a "short bootloop" like this before and knows how to solve it, please let me know!

Bootloader is still locked fyi, flashing unlock command does not work.

I can still use mtkclient to manually flash in any partitions. Flashing seccfg doesn't seem to help.

Still looking for the stock recovery and stock vbmeta partitions from the OTA A12 update if anyone can help me with those. I don't know where to find the stock OTA A12 update that people keep talking about, as the update.zip from teh incremental A11 to A12 update doesn't seem to be quite right.
[OnePlus Nord 2 5G] Raygen:
You can find the OTA A.12 zip file here: https://mega.nz/folder/rQhhHQpA#nNHvPlmzBXwPjmaFpuDa2Q

The partition images are extracted directly from the phone memory, so all images have the exact same dimensions of the partitions size on the phone memory, not the "real" size of the data in them.

In practice, they're filled with lot's of zeros at the end to reach all the same size.

Don't worry about it, both files, smaller ones that came in the OTA files, and the 8Mb+ ones extracted with the tool, are exactly the same.

emmc.win files should be just .img files renamed yes. You can renamed them back to .img or even flash them directly like that.

Try to flash just the vbmeta img from the OTA file and see if it works btw.

I'm about to implement @TheWing fix soon this week in the thread.
[OnePlus Nord 2 5G] Raygen:
The stock recovery present inside the stock firmware .zip is the original one directly from the A.12 update.

The differences you've listed from the old recovery are legit, and present in the stock recovery yes.

Never seen those kind of short bootloops, but try to start fresh by reflashing the stock firmware *without* the eccfg partition + flash vbmeta from the OTA file. And see where that gets you.
[OnePlus Nord 2 5G] Zombnombs:
Hey cheers for the link. Ahhh that explains why all the sizes match. In the OTA 12 file, there are 3 files for vbmeta which are all 4KB in size;

vbmeta.img

vbmeta_system.img

vbmeta_vendor.img

I assume I'll just flash the first one named "vbmeta.img"? What are the other 2?
[OnePlus Nord 2 5G] Raygen:
Yup just the first one is enough. The others two have never been fiddled with, so you already have the stock ones flashed.
[OnePlus Nord 2 5G] Zombnombs:
Took a bit of fiddling around, I think I erased a few partitions by accident (due to following the github page's official instructions for how to unlock bootloader)

Flashing VBmeta from the OTA 12 update file in the mega link above, along with flashing the boot.img and recovery image from the google drive link in the OP should work for most people.

If you're like me and used the "python mtk e cache[and a few other partitions]" command as instructed by the mtkclient's github page's instructions for how to unlock bootloader (which doesn't work for the oneplus nord 2, so don't bother) I found I had to reflash those erased partitions from my nandroid backup as well. Then for some reason, it seems like vbmeta has to be the LAST partition you flash. As I flashed all sorts of other things, and the phone wouldnt boot, until i flashed vbmeta as the most recent one. No idea why that matters though.

Have to step away from my computer but currently the phone seems to boot up just fine, I'm going to leave it at the "welcome setup" screen for now and I'll report back if I see anything unusual.

If anyone else runs in the same issues and got to the fix, just know that if you wiped all partitions, or used someone else's persist.img partition, you'll need to manually flash in the persist image from your own backup or your fingerprint + camera won't work.
[OnePlus Nord 2 5G] martinwildi:
i also had some sort of a victory :).

my device was also stuck (Post#13)

only flashing seccfg.img with the pendrive didnt work, still stuck, and still locked bootloader

i had to flash the correct versions of boot.img, recovery.img and vbmeta.img via mtktools (in my case A.07)

now i can start the phone, it's on the welcome screen

and it seems to have locked bootloader right now.

i have to see later, what i'm doing now :)

@All: thanks for your help!
[OnePlus Nord 2 5G] kkdamion:
@Zombnombs so you managed to get to the "welcome setup" screen. nicely done, so there is some hope for me too.

but first i have to figure out what to do. im not a noob but ive never messed my phone up like this