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A comprehensive guide to the Lenovo Yoga Tab 3 Pro (YT3-X90*) and a Cooked ROM

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Deleted member 5232707

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Complete Newbie, is there a step by step guide to load ROM and not sure does the new ROM upgrade the Android from 6.0 to ?
Read the OP, follow its instructions. You won't be able to upgrade from android 6.0.1 in this tablet, probably ever. This is a Cooked ROM, which means it is a tweaked stock firmware (6.0.1). These tweaks are supposed to help with the grievous performance of the stock firmware, which is unbearable for most owners of this tablet.
 

fengyuclub

Member
Dec 11, 2018
7
0
I read this post carefully, but I didn't see how to unlock the boot loader. After connecting to the computer, there was an exclamation mark in the device manager and the driver was installed. It was very strange. Should I use PlatformFlashToolLite to flash the firmware or use twrp?
Forgot to say, the device is yt3-x90l, the official ota is currently updated to 6.0.1

I have a few questions to ask:
1. What method is used to flash the firmware?
2. I saw other websites that said that Lineage OS can be flashed, https://tweakdroid.com/lineage/lenovo-yoga-tab-3-pro-10-yt3-x90l-yt3/
3. Although I have some experience in writing Android, but I am not very proficient, please do not give some assumptions that I know for granted.
4. Or there are other ways to meet my requirements. My requirement for this device is actually that it has an Android framework, can watch youtube, and can use kodi smoothly.
Looking forward to anyone who can help me, thank you.
 

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Deleted member 5232707

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I read this post carefully, but I didn't see how to unlock the boot loader. After connecting to the computer, there was an exclamation mark in the device manager and the driver was installed. It was very strange. Should I use PlatformFlashToolLite to flash the firmware or use twrp?
Forgot to say, the device is yt3-x90l, the official ota is currently updated to 6.0.1

I have a few questions to ask:
1. What method is used to flash the firmware?
2. I saw other websites that said that Lineage OS can be flashed, https://tweakdroid.com/lineage/lenovo-yoga-tab-3-pro-10-yt3-x90l-yt3/
3. Although I have some experience in writing Android, but I am not very proficient, please do not give some assumptions that I know for granted.
4. Or there are other ways to meet my requirements. My requirement for this device is actually that it has an Android framework, can watch youtube, and can use kodi smoothly.
Looking forward to anyone who can help me, thank you.
To unlock the bootloader and install TWRP go to https://forum.xda-developers.com/th...a-tab-3-pro-root-thread-instructions-t3319666

Then you can follow these instructions https://forum.xda-developers.com/t/...t3-x90-and-a-cooked-rom.4082253/post-85253199

To install firmware (this is the factory software) you need Intel Platform Flash Tool or fastboot (read the OP).

To install this Cooked ROM (this is not firmware) you need TWRP with an unlocked bootloader.

PS and PSA: You can find by yourself if lineage supports our tablet here:

TLDR: Lineage does not support the Yoga Tab 3 Pro. Don't trust that site you linked, it is clickbait.
 

fengyuclub

Member
Dec 11, 2018
7
0
To unlock the bootloader and install TWRP go to https://forum.xda-developers.com/th...a-tab-3-pro-root-thread-instructions-t3319666

Then you can follow these instructions https://forum.xda-developers.com/t/...t3-x90-and-a-cooked-rom.4082253/post-85253199

To install firmware (this is the factory software) you need Intel Platform Flash Tool or fastboot (read the OP).

To install this Cooked ROM (this is not firmware) you need TWRP with an unlocked bootloader.

PS and PSA: You can find by yourself if lineage supports our tablet here:

TLDR: Lineage does not support the Yoga Tab 3 Pro. Don't trust that site you linked, it is clickbait.
Thank you for your reply, thank you again. I am from China, please forgive my English, from Google Translate. After reading the tutorial carefully, it feels a bit difficult. At present, I have installed a third-party youtube app on Marshmallow, and also installed the latest Kodi, which basically meets my use and the projection is normal. As for whether the performance of the system is satisfactory, it will take time. I will report here again, thank you.
 
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Deleted member 5232707

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Thank you for your reply, thank you again. I am from China, please forgive my English, from Google Translate. After reading the tutorial carefully, it feels a bit difficult. At present, I have installed a third-party youtube app on Marshmallow, and also installed the latest Kodi, which basically meets my use and the projection is normal. As for whether the performance of the system is satisfactory, it will take time. I will report here again, thank you.
Don't worry about your English, it's not even my mother tongue. If you feel it's complicated, maybe that's all you need to know to keep yourself away from modding your tablet. We do it mostly because we feel its performance is just lacking. If you are happy with your tablet, then you are good.
 

fengyuclub

Member
Dec 11, 2018
7
0

As if Lenovo's support couldn't be worse... it is.
So, I shared a cooked ROM a year ago and wasn't really great for others. When you flash it you can't get past the setup wizard. The problem is this tablet's firmware comes with a protection mechanism against stolen devices, something called Factory Reset Protection Lock (FRP). This means you can't completely factory reset your device unless Google allows you to or whatever...
To remove this mechanism you can erase the config partition using fastboot, and then format it again into an ext4 partition, because a mountable config partition is required to boot. You need to input these commands in fastboot mode to erase the FRP:

Code:
fastboot erase config

fastboot format config

Then you can flash the cooked ROM as any other ROM, i.e. install the zip file using a compatible TWRP (don't forget to wipe data, boot, system, cache, Dalvik/ART partitions first). The ROM is minimal, based in the latest MM stock ROM, has Magisk (root), better RAM management, it is reasonably debloated and has the signature spoofing patch (to use with MicroG) that you can activate at the bottom of developer options, also includes adb root and USB debugabble by default. The kernel is not secured so it can be rooted with SuperSU if you want to. I included Lawnchair (Fdroid) as default launcher app and a recent version of the Bromite browser (a degoogled Chromium) with the mandatory apps from Lenovo for the device to work.

This cooked ROM is great if you are thinking about just wiping your tablet for any reason, I mean, why not give it a try? Most of the configurations that can make a difference in performance are already implemented.

This was tested and created for the X90F model (2 GB RAM 32 GB ROM, wifi) but, in theory, if you modify two lines in build.prop (ro.radio.noril and ro.lenovo.tablet) following the instructions provided in the same file, it can work on a X90L (4GB RAM, 3G data), but I don't know about RAM management on those.

REQUIREMENTS:
1) Unlocked bootloader
2) TWRP recovery
3*) Unencrypted and formatted data partition (Wipe > Format data partition > "yes")
* This could be done by other unencrypting methods or simply by flashing the ROM and, after installation, Wipe > Format data partition > "yes", reboot. Needs testing.

KNOWN ISSUES:
1) Expect one "random" reboot after first boot, it is normal.
2) Don't upgrade Magisk to v22 yet. Magisk Manager won't work properly in some devices running Android 6.x. Stay with v21.4 for now.

PSA: ALWAYS HAVE A WORKING BACKUP! IF YOU DON'T GET WHAT I WROTE, THAT WAS INTENDED. YOU SHOULDN'T BE MESSING WITH YOUR DEVICE YET.


The link for the updated cooked ROM is: https://centsoarer.ddns.net/s/Y8o3eoBK4Ryx5RP. Feel free to mirror, unless you are afraid of Lenovo's lawyers, but don't forget to share the link. With updated GAPPS: https://centsoarer.ddns.net/s/FPKjgQcmW3CHZCw

My personal version... even more debloated (if you don't need chinese, japanese, korean, or russian support) and with CPU tweaks for my own usage: https://centsoarer.ddns.net/s/jcCDAgNedryGRjo

EDIT: Can someone like this post to give it some visibility? I can't like it myself -_- Yeah... this didn't work.

EDIT 2: Newer versions and a GAPPS updated one.

EDIT 3: These Cooked ROMS will break SmartSide Bar which is one of the few features I like about the stock experience. I am gonna try to find out why. My guess is it works only if the default Launcher is installed it breaks with the Signature Spoofing patches, but If you use this SmartSide Bar then the Updated GApps version may still work with SmartSide Bar, since it lacks the Signature Spoofing patches, and it only includes changes in the init system other than the updates. If this Gapps Updated version work with SmartSide Bar, please report back, since I am not using that version and I am done for the moment with the tablet and the hacking here.

RECOMMENDATION: If you get FCs with heavy apps, try to edit the build.prop with vm.heapsize=256m. Maybe I will update the links to a more stable ones in the next days/weeks. IDK.
After using Lenovo official rom for a few days, it is really stuck and the system performance is weak. Then I flashed MyROM.zip according to your steps, and you can skip into the system without starting the wizard, but the Google service cannot be connected. Follow you The prompt code is clear about FRP. But still use Google services. During the period, you also flashed another x90l rom (ROMx90L_3G.zip) you provided, but you can't use Google services. What should I do now?
 

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Deleted member 5232707

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After using Lenovo official rom for a few days, it is really stuck and the system performance is weak. Then I flashed MyROM.zip according to your steps, and you can skip into the system without starting the wizard, but the Google service cannot be connected. Follow you The prompt code is clear about FRP. But still use Google services. During the period, you also flashed another x90l rom (ROMx90L_3G.zip) you provided, but you can't use Google services. What should I do now?
Sorry, I did not read the quote. Look, I do not own a 3G model, so, It is really limited what I can do at this point. @Nuihc88 shared a boot.img (a kernel) that works for him in this post. After flashing with:

Code:
fastboot flash boot downloaded_file.img

Erase the config partition again, and factory reset your tablet.

If it still won't work, then just restore your backup. As you said, you are from China, and all these builds are based upon the international ROM firmware version. Maybe there is a reason why the Chinese version exists. I really don't know, and the screenshot is not verbose at all.
 
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fengyuclub

Member
Dec 11, 2018
7
0
I tested the 2 roms provided by this post (myrom.zip&ROMx90L_3G.zip, both roms are normal, can be used and can meet my needs, I only need to use third-party youtube and kodi to access my home media server jellyfin) and I have cleared FRP, and I still can’t connect to Google services reliably. The phenomenon is very strange. After I switch airplane mode, there is a small chance that I can connect to Google services, but I just log in to my Google account, and the last step still prompts an error. , I can’t enter the play store. I even used recovery to restore the Chinese version of romboot.img I backed up before. It can enter the system, but the wifi and bluetooth modules can’t be used. I now start downloading https://androidhost.ru/58c again rom, I don’t know if I can try this rom, I know this requires intel tools.
 

fengyuclub

Member
Dec 11, 2018
7
0
It’s all done, most of Google services, jellyfin, kodi, even telegram, tiktok are ok, I don’t know how good it is, I don’t know if it has anything to do with me going to apkmirror to download the latest x86_64 Google service framework file, rom should Is it normal? My hardware version is for sale in China. It's also possible that my network fails intermittently, but it's all right. The only problem is the display when it is turned off and charging. A large intel has no indication of the charging progress. Then there is ROMx90L_3G.zip this rom changed the projection button to the power button, how can it be changed to the original projection button, this is a small problem.
Thanks again @CENTSOARER @Nuihc88
2021-09-24_08-54-59.png
 
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Deleted member 5232707

Guest
It’s all done, most of Google services, jellyfin, kodi, even telegram, tiktok are ok, I don’t know how good it is, I don’t know if it has anything to do with me going to apkmirror to download the latest x86_64 Google service framework file, rom should Is it normal? My hardware version is for sale in China. It's also possible that my network fails intermittently, but it's all right. The only problem is the display when it is turned off and charging. A large intel has no indication of the charging progress. Then there is ROMx90L_3G.zip this rom changed the projection button to the power button, how can it be changed to the original projection button, this is a small problem.
Thanks again @CENTSOARER @Nuihc88 View attachment 5417261
I did change the behavior of the projector button because it is common that, in time, it ends up all smashed and useless. It is easy to revert, though. Check this post.
 

fengyuclub

Member
Dec 11, 2018
7
0
I did change the behavior of the projector button because it is common that, in time, it ends up all smashed and useless. It is easy to revert, though. Check this post.
1、Nothing else is a problem. The main problem is the display when charging in the off state. A large Intel has no signs of charging progress. After all, charging in the off state is a frequently used scene.
2、I also have the problem with this post. Unverified adb devices, I don’t know where your adb commands can be executed? like this command "adb shell wm size 1400x2240"
 
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Deleted member 5232707

Guest
1、Nothing else is a problem. The main problem is the display when charging in the off state. A large Intel has no signs of charging progress. After all, charging in the off state is a frequently used scene.
2、I also have the problem with this post. Unverified adb devices, I don’t know where your adb commands can be executed? like this command "adb shell wm size 1400x2240"
I won't be able to help you here. My time with messing with the tablet is over and what is not in the thread has been forgotten. If the ROM works, that's gonna be all from me, everything else is on you. I hope you share anything you find useful.

I do remember, though, I had a problem similar to that described in your cited post. I think, but I'm not sure, it was related to a setting in the build.prop file... maybe ro.secure=1 is still there? Try to change it back to 0. If it doesn't help, well, I'm out of ideas.
 

fengyuclub

Member
Dec 11, 2018
7
0
I won't be able to help you here. My time with messing with the tablet is over and what is not in the thread has been forgotten. If the ROM works, that's gonna be all from me, everything else is on you. I hope you share anything you find useful.

I do remember, though, I had a problem similar to that described in your cited post. I think, but I'm not sure, it was related to a setting in the build.prop file... maybe ro.secure=1 is still there? Try to change it back to 0. If it doesn't help, well, I'm out of ideas.
(y)
 
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Deleted member 5232707

Guest
I'm putting the ROM files offline and getting away from XDA for a while. Please don't DM me for the files. If you are looking for them, ask others in this thread. Good bye.
 

Nuihc88

Member
Aug 12, 2021
11
5
Finland
Decided to mirror the most recent ones; also added my own fixes and tweaks to the 3G version...

ROMx90F_wifi:
ROMx90L_3G:

...obviously these come with no support. Use at your own risk.
 

calualeaf

Member
Jul 23, 2011
14
1
@Nuihc88 thanks for sharing the files. I tested the Rom on yt3-x90L 4GB/64GB it is a great improvement compared to the stock ROM. :)
The only issue I faced was the one mentioned above by @fengyuclub
The main problem is the display when charging in the off state. A large Intel has no signs of charging progress. After all, charging in the off state is a frequently used scene.
Maybe do you have an idea how to fix this problem? I checked already the suggested solution but there is no "ro.secure=1" in build.prop file.
 

Nuihc88

Member
Aug 12, 2021
11
5
Finland
@Nuihc88 thanks for sharing the files. I tested the Rom on yt3-x90L 4GB/64GB it is a great improvement compared to the stock ROM. :)
The only issue I faced was the one mentioned above by @fengyuclub

Maybe do you have an idea how to fix this problem? I checked already the suggested solution but there is no "ro.secure=1" in build.prop file.
I have the same problem and no idea how to fix it. I would guess that a solution would require messing with the bootloader, which has a high probability of bricking the device; so i'm not even going to try solving this without first fully understanding the issue, but haven't been able to find any usable info.
 

calualeaf

Member
Jul 23, 2011
14
1
I have the same problem and no idea how to fix it. I would guess that a solution would require messing with the bootloader, which has a high probability of bricking the device; so i'm not even going to try solving this without first fully understanding the issue, but haven't been able to find any usable info.
thx for the quick reply. I think I can live with the Intel Logo :) but as far as i can see the device doesn't charge at all when it was shut down before connecting the cable. I assume there might be a chance to brick the device when it ran out of battery power. You can't start it to charge it. Do you know any workaround to charge it while it has 0% power and the OS is shut down?
 

Nuihc88

Member
Aug 12, 2021
11
5
Finland
thx for the quick reply. I think I can live with the Intel Logo :) but as far as i can see the device doesn't charge at all when it was shut down before connecting the cable. I assume there might be a chance to brick the device when it ran out of battery power. You can't start it to charge it. Do you know any workaround to charge it while it has 0% power and the OS is shut down?
It seems to start charging for me even with the intel-screen, but i think you'll need to use a good charger rather than a random USB-port as power source as the intel-screen keeps the display on at all times, thus adding it's own additional power-draw of maybe 300mA or so.
 

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    I will try another charger, but I don't know if this is the issue. Normaly when I plug in the charger the LED ring around the power button is pulsating. While it shows the Intel screen the LED ist off. I did a little research and find a workaround which makes the behaviour a little bit better, after this command:
    "fastboot oem off-mode-charge 0"
    in fastboot, the tablet dosen't get stuck with the intel screen. It starts automatically when you plug in a cable. But I don't know what happens when the battery is to low to start. Maybe I will force the tablet with tasker to shutdown at 15%. That should help a little bit.
    I'm fairly sure android devices don't really care whether they are running off battery or external power as charging circuits must be able to operate independently of any kernel or drivers anyway. Things like charging indicators (blinking lights) however, sometimes require some simple software. I've already had the battery run down to 0% on me once and that didn't lead to any problems.
    That said, i do believe the command you used is a nice tweak as it both avoids the whole 'hold for 10 seconds to turn off' situation and reduces energy waste from the intel-screen keeping the display powered on the whole time.

    - Can I use the data enabled TWRP in @joesnose rooting post? If not where can I find the one compiled by CENTSOARER?
    Sure, that is what i still use myself, CENTSOARER's TWRP had a few unresolved problems and wasn't nearly as thoroughly tested.
    - Ever since I traded my 2GB model for the 4GB model the wifi keeps acting up, where it simply dissapears (can't enable or disable untill reboot) and I seem to recall some others having this problem which seems memory leak related; would this cooked rom mitigate that issue with the tweaks made to RAM?
    I can't say for sure as i never encountered the issue myself, but as the performance of these cooked ROMs is on a class of it's own compared to the official ROMs, it wouldn't surprise me if the problem never surfaced again.
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    Deleted member 5232707
    THESE COOKED ROMS ASSUME YOU HAVE ALREADY AN UNLOCKED BOOTLOADER AND TWRP AS RECOVERY SYSTEM. You can flash them using TWRP, after wiping ART, cache, data, boot and system partitions.

    FINAL RELEASE: Well... this is the final release from me and it is specifically for the WiFi model. I hope it is worth it for you. It is more stable and somewhat updated, anyway, if you use a X90F (wifi model) you will probably like it. The other versions are still up for whatever reason. Here's the link. Follow this guide by @Quardah if you are coming from a factory ROM. Go to post 46 if you can't get past the setup wizard. A barely tested (by @Nuihc88) version for the 3G (X90L) model can be found here.

    NOTICE: If you find this work useful, mirror it. I won't be hosting it for free forever and it is becoming a burden to my Nextcloud installation. One would say this is a pretty much forgotten thread, but I'm seeing almost daily download activity. I'm putting the ROM files offline now and getting away from XDA for a while. Please don't DM me for the files. If you are looking for them, ask others in this thread. Good bye.

    ||||||||||||||||||| FROM HERE IS JUST INFORMATION YOU PROBABLY DON'T NEED |||||||||||||||||||
    APRIL 9, 2021: You can find in these links a new version of the cooked ROM.
    The link for the updated cooked ROM is: https://centsoarer.ddns.net/s/Y8o3eoBK4Ryx5RP. This is a version with GAPPS updated: https://centsoarer.ddns.net/s/FPKjgQcmW3CHZCw. Feel free to mirror, unless you are afraid of Lenovo's lawyers, but don't forget to share the link.

    My personal version... even more debloated (if you don't need chinese, japanese, korean, or russian input support/apps) and with CPU tweaks for my own usage: https://centsoarer.ddns.net/s/jcCDAgNedryGRjo

    KNOWN ISSUES AND SOLUTIONS:
    1) One random reboot after the first boot will happen and it is normal.
    2) I'd reccommend to stay with Magisk 21.4 for a while, Magisk Manager >21.4 won't manage your extensions.
    3) If you can't get past the initial Setup Wizard check post 46. Basically you have to boot into bootloader, erase the config partition and format it again.
    4) Needs confirmation, but versions with signature spoofing patches seem to break Lenovo's SmartSide Bar.


    JUNE 12: Fast update on the Cooked ROM and TWRP and KERNEL. They are not as universal as I implied before. Proceed carefully since they may not work four your device/firmware. Make a Nandroid backup and only flash with testing purposes.

    JUNE 5: So, I know this is not what everybody who owns this tablet wants to have (that is Android 9 or 10 of course) but, in recent weeks Lenovo updated the firmware of this tablets. It still is a Marshmallow one and it still sucks big time but I took it as a base and cooked it to deliver a newer TWRP recovery with compression, a flashable modified kernel and a cooked flashable stock ROM to free the owners of this tablets from the treacherous path of making this hardware to work properly. If you want a better overall experience and are in stock firmware you just need to Unlock your bootloader, flash TWRP, Format data partition (not only wipe), Wipe Cache, Dalvik/ART, System and DATA and flash the Cooked ROM to put this tablet in a sweeter spot. For details go to post #2!

    JUNE 3: Been trying to get to know some of the source code available for Cherry Trail devices and I am fairly lost at building TWRP from source. Anyway, I ported a newer TWRP recovery IMG file for the YT3-X90F (maybe L, X, Y and Z) from the TWRP image for the Chuwi Hi10 Pro tablet from here, using AIK-Linux. The result is in the second post labeled as beta, since I only tested in the YT3-X90F model, running lollipop firmware. So far, it works fine flashing ZIP archives, backing up and restoring backups. Advantages? Well, backups are way lighter if you enable compression (like half the size), higher resolution, twrp turns off the screen with a timeout and whatever made them bump from version 2 to 3. While I could port a newer TWRP version, I just wanted to have lighter backups with compression... so maybe it is what it is :eek:.

    ORIGINAL POST STARTS HERE. This is general information that I collected for geeks or desperate users that bricked their tablets. When I started this post it wasn't intended to produce a cooked ROM that would include most of these hacks. You don't need this if your tablet boots to Android or TWRP. You also don't need this if you are ready to flash the cooked ROM.

    (This is a lenghty post. I suggest you to navigate by section header and find the one you might need.)

    There are several Lenovo Yoga 3 tablet models out there and, while some of them enjoy of prime community support as the Yoga Tab 3 Plus, this Intel Atom powered tablet is pretty much forgotten and, at the same time, users were recently buying this tablet, which is a great piece of hardware but has the most terrible support by Lenovo.

    Basically, this is that Lenovo tablet with an attached projector and an Intel Atom Cherry Trail x5 Z8500. There are several models, though, to my knowledge they vary in their code names in the last letter, the two most basic ones (2GB RAM, 32 GB ROM) are the YT3-X90F and the YT3-X90L, the former connects to the internet by WiFi and the latter being the one with LTE/Phone capabilities. There are other models, though, and they vary on the amount of RAM and internal storage. Apparently, the YT3-X90[YX] models (the 4/64 GB refresh) have some use for these firmwares we describe, but in a very specific way, if you own a Y or X model, keep reading, especially the next section.

    Lenovo support has been terrible (there are no words to describe it, really), so they launched this tablet with Android 5.1 Lollipop and they maintained it for a while but were very slow to deliver Android 6.0 Marshmallow. In fact, there was already Android Nougat, when they sent the Marshmallow update. Nevertheless, the update was bad. Performance issues were always a thing and some functionality went lost in the update (less intuitive multiple windows, a crippled recents activity/screen, and a laggy overall experience). Bottom line, they launched a curated Android Lollipop 5.1 firmware with security updates until March 2016 (striked because the last lollipop update f*cks up my sensors, except the light one) and a half-assed Android Marshmallow 6.0.1 firmware.

    Of course, at the time, I'm guessing most of us upgraded to Android Marshmallow 6.0.1, hoping the upgrade would fix the issues in Lollipop or with security patches in mind. The reality was that Android 6.0.1 wasn't nearly as maintained as 5.1 and security ambitions went nowhere. So, we got the upgrade all right, but at this point, both Android versions can be considered inherently insecure and we really shouldn't be using it for sensitive work.

    OK, there are several Android 5.1 and 6.0 firmwares, you can recognize them because they are all over the internet typically in a compressed format. For example, this firmware hosted in androidhost.ru named:
    YT3-X90F_ENG_S100265_1601281130_WW24_ROW
    Is a firmware for the Lenovo Yoga Tab 3 (YT3) Pro (X90) Wifi Version (F). The ENG part is an indication of the build type, ENG is an engineer build while USR is probably a firmware for the end user (this is common now that I know a bit more about AOSP source code), it is a Lollipop firmware (S1, Marshmallow would be a S2) with update version (00265), date of compilation and a good estimate of its security patch (1601281130), the WW24 is the weekly release version of the Android kernel for Intel devices (the latest, in May 2020, being WW31 which is exactly the same as WW28 and not updated since 2016), the final part means it is the global ROM version (ROW, opossed to the Chinese version CN). This is the latest Lollipop firmware I am aware of, so, as an example, an imaginary Android Marshmallow Chinese firmware for the LTE version of the Yoga Tab 3 would look like:
    YT3-X90L_USR_S200013_1610141535_WW24_CN
    As an additional note the Chinese ROMS, I presume, are not trusty but they are also Google-free for what it's worth. On the other hand, they ship with a "Lenovo Services Framework" that should be as intrusive as the Google Play Services. Oh, also, baidu and yandex, and, really, any less traditional search engine can help you find a fitting firmware.

    I did test several firmwares, chinese and global, lollipop and marshmallow and the safest and easiest way to flash them is by using the Intel Platform Flash Tool Lite . I can't say I trust in this site, but it hosts a handy tutorial on how to use it, though, is pretty intuitive. The software exists for Mac, Windows and Linux, be sure you are in, at least, the 5.8.x version, this is important to avoid the need to install some special drivers separately as a pre-requisite. Grossly, Intel Flash Tool Lite works like this:

    0) Turn off your tablet if it is on.
    1) Launch Intel Platform Flash Tool Lite.
    2) If your downloaded firmware is in zip format load it with the blue "Browse..." button.
    2 bis) OR, if your firmware is in other compressed formats, uncompress it first. After this use the "Browse..." button to load the "flash.json" file.
    3) In Configuration option select "blank" if it isn't set already. Optionally, un-tick the "On-demand flash" option to have more control of this process. Also, maybe you can use the "erase" configuration here.
    4) Start your tablet in DNX mode. To do this, press Vol- and hold it, then Vol+ and keep holding both, then press the Power button until it turns on and you see the Lenovo logo and some text indicating you are in said mode.
    5) Connect your Yoga Tablet with a USB cable and your Intel Platform Flash Tool Lite windows should show it as detected. Now you can proceed using the blue "Start to flash" button.
    6) Keep an eye on your tablet, since some firmwares will prompt to set some more options. Unless you know what you are doing, answer "Yes" to any question.
    7) Reboot and wait.

    If a couple hours have passed and the tablet hasn't booted, maybe you should try another firmware.

    IMPORTANT NOTE AND INSTRUCTIONS FOR YT3-X90Y AND POTENTIALLY YT3-X90X USERS: I don't know the rules in xda about linking to other forums but in certain forum there is an answered question about the Y model (the 4/64 GB WiFi only refresh) on how to flash a firmware. Instructions are the same as I gave in this section, except, apparently, you need to do it twice, first with the ENG version and the second time with the USR version except you are not using the flash.json file, this time you'll browse for the flash_factory_1st_stage.json one and the factory1st configuration in fastboot. It is not clear what are the consequences of not doing it this way or what if you combine different firmware versions (it would be interesting to have a tester here). Notice please, these firmwares are marked for the YT3-X90F model. So, clarifying:
    1) Follow the instructions above to flash the YT3-X90F_ENG firmware.
    2) Power off your tablet.
    3) Boot into bootloader (not in DNX, you need to boot into bootloader by powering on while holding Vol+).
    4) From the YT3-X90F_USR firmware folder use Intel Platform Flashing Tool Lite to load the flash_factory_1st_stage.json and select the factory1st configuration.
    5) After flashing the USR firmware, reboot and you should be good to go.

    METANOTE: This wasn't tested by me, please do this only when you are hopeless with your hardware. This is just an educated guess but I bet it works the same with the YT3-X90L (the LTE version 2/32 GB Yoga Tab 3 Pro) and the YT3-X90X (the 4/64 GB refresh).

    ALTERNATIVE WAY TO FLASH A STOCK FIRMWARE (ADVANCED USERS, requires fastboot)
    Well, there is no need, really, to use that Intel tool. In my search for a lollipop firmware (I wanted to downgrade from Marshmallow) I found the firmware YT3-X90F_USR_S100195_1512052308_WW24_ROW in www.firmware247.com or www.androidfilehost.com (IMPORTANT: please read the note on downgrading to Android 5.1 Lollipop in the note at the end of this section). This firmware was special since, if you are in Windows and have fastboot executable ready and in place, you can run a script (run_me.bat) in the Windows terminal (CMD) or Powershell to flash the firmware semi-automatically. I think this firmware was modified, though, since I found differences in the boot.img when compared with stock firmwares. This script is credited to XDA members @ionioni and @joesnose and you can replicate its steps if you:

    0) Turn off your tablet if it is on.
    1) Start your tablet in DNX mode. To do this, press Vol- and hold it, then Vol+ and keep holding both, then press the Power button until it turns on and you see the Lenovo logo and some text indicating you are in said mode.
    2) Connect your tablet to your fastboot enabled PC using a USB cable.
    3) Input "fastboot flash osloader loader.efi"
    4) Wait 5 seconds to be sure the loader flash finishes.
    5) Reboot into Bootloader. If you don't know how, one way is to hold Vol+ and Power on your tablet.
    6) Input "fastboot oem unlock" and confirm using Vol keys to select the right option and the Power button to enter it.
    7) Input "fastboot flash system system.img"
    8) Input "fastboot flash boot boot.img"
    9) Input "fastboot flash recovery recovery.img"
    10) Input "fastboot flash bootloader bootloader.img"

    Follow your instincts, since I don't know if these IMG files are always named the same. You can get these IMG files from downloaded sources or dump them yourself using dd command.

    NOTE ON DOWNGRADING TO ANDROID LOLLIPOP 5.1: So, one of my main concerns has been to go back to Android Lollipop. There is a last version of Lollipop from where you can upgrade to Marshmallow with a security patch from March 2016. Nevertheless, you MAY end up loosing other sensors except the light one. If this happens, you need to use a complete firmware flash using Intel Platform Flash Tool Lite. In my experience, some boot images are not compatible with other weird partitions like country or misc.


    The first boot takes some time even amounting for the time of the setup itself. By the time you are in the launcher tapping on app's icons you think there's nothing wrong with our device, but after some apps are in memory, you notice some lag. You think "OK, it is updating, but soon it'll settle", but it does not. So, you reboot again after updates and fire up a terminal emulator and connect to your tablet using a USB cable with USB debugging turned on and issue a free command to find something like this:

    Code:
                  total         used         free       shared      buffers
      Mem:      1950372      1820964       129408            0         7756
    Swap:       524284        10740       513544
    Total:      2474656      1831704       642952

    Which means you have a total of ~2.5 GB (this is the 2 GB model). So, did I download that extra half GB of RAM or Lenovo was feeling generous? Well, no. The issue here is Lenovo built the kernel with zRAM support which is a technology included in Linux that reserves space in RAM to quickly compress and uncompress pages of data exceeding our physical amount of RAM installed (2 GB). This is not Virtual Memory as in a swap file/partition or Windows' Page File inside storage media. zRAM literally reserves a fixed amount of physical RAM space (blocks) to expand it by compressing data. The consequence is you loose "fast RAM" (THE RAM) and gain some "slow RAM" (the zRAM). You also sacrifice some CPU power to compress/decompress data and, with this, some battery juice is also lost.

    That does not sound like a terrible trade-off for a RAM-limited device, one would think. Another interesting thing would be WHEN to send this piling data in "fast RAM" to the compressed space and WHEN to get it back. Two parameters control the WHENS, one is called "swappiness" (when to send it to the compressed space, the "slow RAM") and the other may be the "vfs_cache_pressure" (when to uncompress it and send it back to the "fast RAM"). And this is where the main problem is, really, because the kernel, Linux, is pressing the RAM constantly to send some less prioritary data to "slow RAM" and, at the same time, is trying constantly to send compressed data back to the "fast RAM". Summarizing, this kernel behavior is practically minimizing the fast RAM amount and usage while maximizing the "slow RAM" usage. This is nuts, by default a swappiness and a vfs_cache_pressure of 100 are not even default for servers, these parameters extremely prioritize that processes can get done no matter how slow they get, and they are even more nuts when Android is designed to work without swap space.

    What that free command is telling us is the tablet is using the "slow RAM" even when we only just turned it on. Fortunately there are two ways to fix this problem: one is to completely disable zRAM, the other one is to use ZRAM a whole lot less by tweaking the swappiness and vfs_cache_pressure parameters. This can be easily done with the following sentences in a rooted tablet:

    Code:
    # echo 5 > /proc/sys/vm/swappiness
    # echo 50 > echo 5 > /proc/sys/vm/vfs_cache_pressure

    Or, to regain the whole fast RAM:

    Code:
    # swapoff /dev/block/zram*

    One caveat of the first method, reducing swappiness, is there is still a lot of RAM (one quarter of the whole RAM in a 2 GB device) reserved as "slow RAM".


    SOME ROMS DID NOT ENABLE KERNEL SAMEPAGE MERGING, UNFORTUNATELY

    Additional to the sorry implementation of zRAM, some firmwares support a fabulous Linux tool to reduce RAM usage called Kernel Samepage Merging (KSM) but they don't use it by default. This software runs at kernel level, so, it really is CPU-wise inexpensive and, opposite to zRAM it can actually recover some RAM usage by reducing the amount of data flagged as redundant in physical RAM by merging it. KSM is good for you and you should have it always enabled by issuing the following command as root:

    Code:
    # echo 1 > /sys/kernel/mm/ksm/run


    STOP WRITING AND FIX MY RAM! PLEASE!

    Well... are there any people interested on this? With the above information you can write a script to execute at boot. Something like this should work in any version of the firmware:

    Code:
    #!/system/bin/sh
    
    # Mount system as rw
    busybox mount -o remount,rw -t auto /system
    
    # Tweaking swappiness in zram
    echo "5" > /proc/sys/vm/swappiness
    echo "50" > /proc/sys/vm/vfs_cache_pressure
    
    # Activating Kernel Samepage Merging
    echo 1 > /sys/kernel/mm/ksm/run
    
    # Remount system as ro. noatime option for faster and volatile system
    # busybox mount -o ro,remount,noatime /system
    busybox mount -o ro,remount /system
    
    exit 1

    Or, you can unpack the boot.img and modify the init.cht_ffd.rc (lollipop) or the init.r2_cht_ffd.rc (marshmallow) files to write these values as default... or, if there is interest for something easier, I can produce this boot.img files for you to flash using fastboot.

    ROOTING THE LENOVO YOGA TAB 3 PRO (YT3-X90[FL])
    Here I am not gonna write a lot. Instructions were given in this thread. I'd only recommend to put vm.targetutilization at 0.8 top 0.85 in system/build.prop

    After rooting, debloat your firmware. I use the app "/system/app mover" from Fdroid to convert to user apps and uninstall them. Also, if rooting is not your cup of tea, you can install AppOps software to freeze all those apps that you don't use regularly. Also, I couldn't patch my services.jar for Signature Spoofing with Nanodroid patcher in the most recent lollipop firmware, but it did work in Marshmallow... anyway I'll do it manually.

    ARE YT3-X90F AND YT3-X90L FIRMWARES INTERCHANGEABLE?
    I own a WiFi only device (YT3-X90F) so I can't assert they are interchangeable. If I owned the LTE version and use a WiFi firmware I would expect to loose LTE functionality. Now, on the other direction is more interesting because I've been using a LTE firmware version for weeks (as a matter of fact, the one joesnose linked in his How-To debrick this tablet, flashed with the instructions I posted for advanced users it even updated to recent 2020 firmwares). The only tweak you need for this to work well is to add "ro.ril.disable=1" in the build.prop file. So, yes, firmware for the LTE version work in the WiFi version but kind of not vice versa.

    No news here. All capable people interested on developing for this device are all done with Lenovo and their attitude against Open Source. Don't expect your situation to change.
    I'm happy to know there are still a couple of developers interested on this device. I won't cite them by linking their names but they are OOEvil and alquez, the first guy is trying to make a Generic System Image (GSI) ROM compatible with our tablet, I don't know the details so I wouldn't go further. Alquez has been active in this thread and, while he is trying to figure out how to build a kernel, he believes the best way to start having some alternative to official Lenovo firmware is by using a firmware kernel (a prebuilt kernel) to, first, build a more up-to-date TWRP recovery.img and from there try to build CyanogenMod 13, which was based on Android Marshmallow 6.0.1. My guess is newer Android versions wouldn't work if we can't build the kernel from source.

    PHOTO ALBUM OF YT3/X90Y BIOS
    This photo album documenting every screen option in the BIOS of the Yoga Tab 3 Pro may or may not help someone, but it contains a lot of useful hardware information and guidance for those attempting to boot something else than the original Android 5 or 6 firmware. Using this options, that are accessible through F2 at boot with an attached USB keyboard, you could try Linux distributions on the tablet or even attempt to run Windows, @alquez informs it works fine with a recent distro but the mainline kernel is lacking touchscreen and battery support. This is absolutely his work and he asked me to share it. I hope it serves someone. It is hosted in a rather obscure website but it was the only reasonable placeholder I could find for the 321 photos.

    Hope this helps someone, I just didn't want to keep it to myself. Have a nice day!
    4
    D
    Deleted member 5232707
    Just remember, if your tablet is 3G capable I strongly suggest that you modify the line "ro.lenovo.tablet=wifi" to "ro.lenovo.tablet=3gdata" and remove the line "ro.radio.noril=true" to your build.prop file in /system. To do this you can use the section Build.prop Editor of the Kernel Adiutor app or you can do it manually if you have already a method to modify system files. If you do not use mobile data at all, you may leave the build.prop as it is, you'll save a lot of battery by using only wifi.

    ONLY FOR TESTING: Cooked ROM, newer TWRP and tweaked kernel

    ONLY TRY THESE FOR TESTING PURPOSES, THE TWEAKS ARE ALL SAFE TO USE BUT ONLY FLASH FOR TESTING PURPOSES, PLEASE. FIRST, TRY TO USE FASTBOOT TO BOOT THE boot.img FILE WITHOUT FLASHING: IF IT BOOTS GO AHEAD AND TRY THE OTHER FILES (fastboot boot boot.img). THE TWRP IS NOT AS STABLE AS THE OTHER ONE HERE AT XDA BUT ALLOWS TO USE ZIP COMPRESSION IN BACKUPS. I AM NOT GONNA BE AROUND. IF YOU TRY SOMETHING MAKE A BACKUP FIRST. THIS DEVICE IS MESSY AS F*CK.
    I wrote a very detailed guide about these files I uploaded to my Nextcloud that include the newer TWRP-3.0.2, a TWRP flashable Cooked ROM and a separate kernel (boot.img) in case your system is already setup, but the post went to some XDA void and didn't upload. These are based on the YT3-X90L latest firmware, but they work on the X90F model too. The TWRP should work with Lollipop and Marshmallow firmwares.

    I can't write everything again, so, the kernel contains better management of RAM and emmc (internal) memory, a 256 MB zRAM space instead of 512 and a more conservative approach to LowMemoryKiller.

    The cooked ROM includes the described kernel and debloated apps, it's already rooted with Magisk (you can unroot with Magisk Uninstaller), an updated Busybox build, su.d support (I plan to use it with AFWall+), zipaligned apps, etc. It is for the X90L but possibly works for the other Yoga Tab 3 Pro models. It works for the X90F but it will reboot once after the first boot because the RIL configuration times out. To install the cooked ROM you need to:

    0) Know that by doing this you will loose pretty much everything in your tablet. You start from scratch if everything goes smooth, if not you could possibly end up with a system without an OS. The usual stuff when you are customizing your system.
    1) Boot into TWRP and make a Nandroid backup. IT IS IMPORTANT because @joesnose had problems with a "random reboot" and lost Bluetooth/WiFi after it. I am trying to look into this. The only difference is his tablet has 4 GB RAM and probably a different firmware.
    2) Wipe cache, Dalvik/ART, System and Data in TWRP - Wipe, Advanced Wipe menu. If your tablet is encrypted, or in factory firmware you also need to explicitly use the button "Format Data partition" and confirm writing "yes" in the format procedure prompt. You will loose any configuration made to your tablet.
    3) Install the superr_stockMM.zip wich is flashable by selecting the file from your Internal tablet memory, using the Install button in the main TWRP interface.

    FOUR IMPORTANT NOTES TO COMMON ISSUES:
    If you come from a stock firmware your data partition is encrypted. You need to pass a blank password in TWRP to continue to use the custom recovery. You also need to format data partition before flashing the cooked ROM.

    If your tablet is WiFi-only I strongly suggest that you modify the line "ro.lenovo.tablet=3gdata" to "ro.lenovo.tablet=wifi" and add the line "ro.radio.noril=true" to your build.prop file in /system. To do this you can use the section Build.prop Editor of the Kernel Adiutor app or you can do it manually if you have already a method to modify system files. In Lollipop firmware you use "ro.ril.disable=1" instead of "ro.radio.noril=true" to get the same effect: sort of a conversion to WIFI-only tablet from LTE models. I'd argue this is useful to do if you are gonna be without LTE connection/service for long periods of time and I can think a couple of other uses.

    Do not use stock Lenovo launcher unless you uninstall Magisk... they are incompatible for reasons I don't care to know and the Launcher will constantly FC (it is a pain in the arse).

    If you are still expecting better performance I am sure there are some tweaks left in RAM management but it wont go too much further in 2 GB devices. Instead, you may consider to lower your display resolution and pixel density to something reasonable as 1400x2240 or even 1200x1920 maintaining the same aspect ratio. To do this you do not need to have root but you need to interact with the tablet using ADB. First change the size of your display:
    Code:
    adb shell wm size 1400x2240

    Then adjust your density:
    Code:
    adb shell wm density 260

    If still is not enough you can go even further with 1200x1920 and 224, use the same method to go back to stock with 1600x2560 and 300 to 302. This won't need a reboot but will probably cause an inconsistent UI that will lead to FCs and random reboot. You can just reboot after applying these tweaks. Unless you are really sight-gifted you won't notice a lot has changed but you will be dealing with 2.x Mpixels instead of 4.x Mpixels and that will help with your overall performance as well as your battery life sacrificing a pixel count that most of the people wouldn't even notice. If you did this correctly, in the next boot sequences you'll notice an offset on the Lenovo orange logo.

    It is important to say that your display supports 1600x2560 pixels physically, but I'm assuming the GPU has no dedicated RAM and uses the device's, so, by reducing the quantity of pixels the GPU needs to deal with, the pressure on the device's RAM is also reduced.

    EXTRA TIP: If boot annoys you just delete /system/media/boot.wav, bootanimation.zip and shutdownanimation.zip and you'll get a silent boot and the generic android boot animation.

    Hope you enjoy your tablet!

    TWRP-3.0.2.0- BETA: Again, this is not a flashable zip. Uncompress first and test the recovery system using "fastboot boot twrp_yt3-x90f_beta.img". If everything works for you, you may want to flash it permanently rebooting to bootloader and flashing with "fastboot flash recovery twrp_yt3-x90f_beta.img". Remember I did not test this in Marshmallow yet.

    FEATURES:
    - Fixed RAM issues (swapiness 10, vfs_cache_size 50 and disabled dynamic low memory killer tweaks and minfree values).
    - Reduced zRAM size to only 256 MB.
    - Tweaked interactive CPU scheduler to use other than min and max frequencies (but still responsive). The tweaks are based on the Advanced Interactive Governor Tweaks Guide. This may save battery life.
    - Max frequency capped to 2.08 GHz (this is not great if you are a gamer). This tablet throttles when using max frequency for a long time, so, to save battery and keep it cooler I tweaked the CPU to run slower.
    - Tweaked I/O schedulers to use deadline governor and read ahead cache to 640 kb (used benchmarks to get to this value).
    - Force encryption disabled (to avoid applying ionioni script after flashing). Still needs to format data partition. You can encrypt your data partition later through Configuration -> Security user interface.
    - Implemented native init.d support (not su.d anymore and no need to root the main OS).
    - Busybox updated.
    - Rooted with Magisk by default ( you can use Magisk uninstaller to unroot).
    - Debloated apps. I also deleted Lenovo User Experience Program which was asking for root privileges even when you don't opt in to the Lenovo UE Program at setup wizard. I find this behavior shady.
    -Multi-window mode is available in Developer Options and needs to be activated by you. In this mode if an app is compatible with multi-window mode you can double-tap on its title bar to enable Window mode. This function was more transparent in Lollipop firmware but it is still there in Marshmallow firmware if you change the build type to userdebug instead of user in build.prop (that's how I enabled it in the Cooked ROM).
    - There are also other tweaks in VM and KSM.

    And that's it, I'm not trying to change a lot, only the fundamental issues. But I suggest some other tweaks up there.
    2
    I had a look at the original 3G-version's 'boot.img' with 'Android Image Kitchen' and noticed that it's '/charger', '/sbin/watchdogd' & '/sbin/ueventd' had different character encoding than in the WiFi-version, which caused some text editors to read them with a '/' missing; i'd guess that's probably the reason it wasn't booting.
    Anyway, i ended up making my own boot.img with 3G features re-enabled and some additional tweaks...
    I have no idea what the '/sbin/efiprop' in WiFi version is for, but i left it in there regardless.
    Afterwards i also needed to re-patch the image with Magisk from TWRP to make root-features work again...
    I can't make any guarantees about the quality or reliability of this .img as this is my first time editing one, but here it is anyway...

    PS.
    If anyone wants to use my boot.img, make sure to repeat the re-patching step, as i have no idea how to export the re-patched boot.img in an usable format.
    1
    Thanks for the new feel.

    This is great, glad to see a developer picking up this tablet. It's a fine machine with an unfortunately small user base and has never really seen any development apart from ionioni s efforts and he didn't even own one, lol.

    Edit: *Thank for the new twrp * auto correct!
    1
    I will try another charger, but I don't know if this is the issue. Normaly when I plug in the charger the LED ring around the power button is pulsating. While it shows the Intel screen the LED ist off. I did a little research and find a workaround which makes the behaviour a little bit better, after this command:
    "fastboot oem off-mode-charge 0"
    in fastboot, the tablet dosen't get stuck with the intel screen. It starts automatically when you plug in a cable. But I don't know what happens when the battery is to low to start. Maybe I will force the tablet with tasker to shutdown at 15%. That should help a little bit.
    I'm fairly sure android devices don't really care whether they are running off battery or external power as charging circuits must be able to operate independently of any kernel or drivers anyway. Things like charging indicators (blinking lights) however, sometimes require some simple software. I've already had the battery run down to 0% on me once and that didn't lead to any problems.
    That said, i do believe the command you used is a nice tweak as it both avoids the whole 'hold for 10 seconds to turn off' situation and reduces energy waste from the intel-screen keeping the display powered on the whole time.

    - Can I use the data enabled TWRP in @joesnose rooting post? If not where can I find the one compiled by CENTSOARER?
    Sure, that is what i still use myself, CENTSOARER's TWRP had a few unresolved problems and wasn't nearly as thoroughly tested.
    - Ever since I traded my 2GB model for the 4GB model the wifi keeps acting up, where it simply dissapears (can't enable or disable untill reboot) and I seem to recall some others having this problem which seems memory leak related; would this cooked rom mitigate that issue with the tweaks made to RAM?
    I can't say for sure as i never encountered the issue myself, but as the performance of these cooked ROMs is on a class of it's own compared to the official ROMs, it wouldn't surprise me if the problem never surfaced again.