# ICS bootloader vs JB bootloader



## scott62185 (Jan 6, 2012)

So, we are being encouraged to flash the Jelly Bean bootloader in jakeday's Jelly Belly rom (great rom and support, btw). Does anyone know what the process is if you want to flash back to an ICS rom (either a nandroid or a new rom) after having flashed the JB bootloader? I have heard we need to flash an ICS bootloader to go back. Does anyone know if this is true? Also, any idea where the ICS bootloader can be found?


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## mldiroff (Dec 18, 2011)

I don't know that this is encouraged, but I flashed the JB bootloader then restored a nandroid of Liquid 1.5 with no issues. Then went back to Jelly Belly with no issues.

Sent from my Galaxy Nexus using Tapatalk 2


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## scott62185 (Jan 6, 2012)

mldiroff said:


> I don't know that this is encouraged, but I flashed the JB bootloader then restored a nandroid of Liquid 1.5 with no issues. Then went back to Jelly Belly with no issues.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


Okay, good to know at least one person's experience with it.


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## JRJ442 (Jun 8, 2011)

scott62185 said:


> Okay, good to know at least one person's experience with it.


I restored to stock 4.0.4 and flashed the Jelly Bean bootloader just because. It'll be fine. I haven't had an issue at all on ics


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## Pathology (Feb 6, 2012)

I restored an AOKP build (40 I believe is what that nandroid was lol) whilst having the JB bootloader installed with no issues, however ymmv. Idk how actually -flashing- a ICS ROM will work though, so do so at your own risk.

Sent from my Galaxy Nexus using RootzWiki


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## v36sedan (Sep 4, 2011)

Do I wipe anything before flashing the JB boot loader?


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## JRJ442 (Jun 8, 2011)

I flashed liquid 1.5 on the jb bootloader. Worked great. Did tons of zipthemer stuff too. Keyboards, mms app. No issues = ) The only difference is probably it works more efficiently with boot times and all. I doubt it would ever bork and install


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## JRJ442 (Jun 8, 2011)

v36sedan said:


> Do I wipe anything before flashing the JB boot loader?


Nope. Just flash it. U could wipe cache and dalvik if ya wanted to. But I don't think its necessary. There isn't any data in the bootloader


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## andrewjt19 (Oct 27, 2011)

This is some good info- Would someone who has already done this thoroughly be willing to put up a quick TUTORIAL for everyone on how to go to JB bootloader and how to revert back to ICS (mostly user preference since JB seems to be fine regardless)? Just a thought. I would but I haven't done it yet; I just got another GN after 4 returns for dysfunctional hardware and was basically waiting for source to be released for an official JB.. A lil paranoid a suppose.. hehe


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## awtenterprise (Nov 5, 2011)

Just another bit to think about, If you plan on flashing to the factory stock image you will need to reflash the ics bootloader. When I was attempting to reimage to 4.0.4 fastboot gave an error about unsupported bootloader.

Just keep both handy, and learn how to use fastboot.....

AdamT.

Edit:

the guide for going back and forth reads like
{fastboot flash bootloader bootloader-toro-primela03.img}
insert JB bootloader .img to upgrade to the new bootloader


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## scott62185 (Jan 6, 2012)

awtenterprise said:


> Just another bit to think about, If you plan on flashing to the factory stock image you will need to reflash the ics bootloader. When I was attempting to reimage to 4.0.4 fastboot gave an error about unsupported bootloader.
> 
> Just keep both handy, and learn how to use fastboot.....
> 
> ...


Okay, good heads up. Would you happen to know where the ICS bootloader is? I've done a search and can't seem to find it.

Sent from my Galaxy Nexus using Tapatalk 2


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## Joesyr (Feb 7, 2012)

scott62185 said:


> Okay, good heads up. Would you happen to know where the ICS bootloader is? I've done a search and can't seem to find it.


http://wiki.rootzwik...ng_Galaxy_Nexus

Relevant files on the pages for the variants of the phone. Not so much a singular "ICS bootloader" as most of the OTA packages had a new one when they came out, but you probably just want to grab the latest 4.0.4 one.


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## awtenterprise (Nov 5, 2011)

Yeah, I found the files on "another" site, can't seem to remember the name of it.

AdamT.

Sent from my Galaxy Nexus using Tapatalk 2


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## RickRom (Jan 4, 2012)

You can find the ICS bootloader on Peter Alfonso's Bugless Beast site

http://download.peteralfonso.com/toro


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## techbeck (Jul 6, 2012)

RickRom said:


> You can find the ICS bootloader on Peter Alfonso's Bugless Beast site
> 
> http://download.peteralfonso.com/toro


Thanks for this...been looking for a flashable ICS bootloader.


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## iPois0n (Jan 12, 2012)

These are mine and contains the 4.0.4 radios as well as bootloader for ICS. I wouldn't recommend flashing this unless your radios are 4.0.2. Also I'm not responsible for anything that may happen to your device during or after flashing. http://db.tt/2XogNVXI


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## 808phoneaddict (Jul 6, 2012)

techbeck said:


> Thanks for this...been looking for a flashable ICS bootloader.


me too! maybe after I download this and save to sd, i can breathe a little easier knowing I can upload the jb bootloader and yet go back to ics and unroot if needed! Awesome! I bet that's your plan too huh?

Sent from my Galaxy Nexus using Tapatalk 2


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## masri1987 (Jun 29, 2011)

Where's the ff radios  also what are the benefits to jb bootloader

Sent from my Galaxy Nexus using Tapatalk 2


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## nexgeezus (Apr 5, 2012)

awtenterprise said:


> Just another bit to think about, If you plan on flashing to the factory stock image you will need to reflash the ics bootloader. When I was attempting to reimage to 4.0.4 fastboot gave an error about unsupported bootloader.
> 
> Just keep both handy, and learn how to use fastboot.....
> 
> ...


Ok so just to get this straight, if I just want to go to jb bootloader and not to stock first, I would do this in adb
(fastboot flash bootloader bootloader-toro-"jbboot".img)?

Liquidized Popcorn on this Nexus.....


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## awtenterprise (Nov 5, 2011)

Use adb, type (adb reboot bootloader)

That puts you in boot loader mode.

Type the fastboot command from there.

AdamT.

Sent from my Galaxy Nexus using Tapatalk 2


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## slow88lx (Jun 7, 2011)

You can use the Gnex toolbox to flash .IMG files. That's how I did it.


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## 808phoneaddict (Jul 6, 2012)

you can use the gnex toolbox to flash the .img file...i also found this site for downloading the factory images...i believe you can use this type of file (.tgz) although Im not sure if it includes the bootloader (im still a newbie)...

https://developers.google.com/android/nexus/images

could someone experienced plz tell me if that would work


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## ERIFNOMI (Jun 30, 2011)

No, you cannot flash those as they are. A .tgz is a compressed archive.


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## 808phoneaddict (Jul 6, 2012)

ERIFNOMI said:


> No, you cannot flash those as they are. A .tgz is a compressed archive.


Ok...good to know... What would you have to flash to get back to the ics bootloader? And would I have to wipe something?

Oh wait I was thinking about flashing it thru the gnex tool kit...still not possible?

Sent from my Galaxy Nexus using Tapatalk 2


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## 808phoneaddict (Jul 6, 2012)

and just to clarify (sorry again for being a noob), an IMG file is the bootloader?? does it standalone as the bootloader??

i recently Nandroid backed up my files and saved it to my desktop, as i was snooping around i seen a "boot.img" file in there (its from before i made major changes and is probably an ICS file)...could i just somehow copy and paste that over the one thats on my phone (if i updated to the JB bootloader) and thus go back to the ICS bootloader?


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## ashclepdia (Oct 10, 2011)

808phoneaddict said:


> and just to clarify (sorry again for being a noob), an IMG file is the bootloader?? does it standalone as the bootloader??
> 
> i recently Nandroid backed up my files and saved it to my desktop, as i was snooping around i seen a "boot.img" file in there (its from before i made major changes and is probably an ICS file)...could i just somehow copy and paste that over the one thats on my phone (if i updated to the JB bootloader) and thus go back to the ICS bootloader?


boot.img is the kernel not the bootloader
the bootloader doesn't get backed up with a nandroid
if you want to revert to ics bootloader, it's just a simple fastboot flash i do believe. but not of a boot.img
for some reason i wanna say it's actually called "bootloader.img" (sorry it's early haven't had my coffee, but i am POSITIVE boot.img is NOT bootloader it is kernel )
as posted on the previous page, go to the galaxy nexus wiki (it's linked on previous page) you can download the ics bootloader img that you can fastboot flash, here is link again 
http://wiki.rootzwiki.com/Samsung_Galaxy_Nexus
just choose toro for the vzw version.
couldn't get direct links yo work for some reason lol
Sent from my Galaxy Nexus using Tapatalk 2


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## blaineevans (Jul 11, 2011)

ashclepdia said:


> boot.img is the kernel not the bootloader
> the bootloader doesn't get backed up with a nandroid
> if you want to revert to ics bootloader, it's just a simple fastboot flash i do believe. but not of a boot.img
> for some reason i wanna say it's actually called "bootloader.img" (sorry it's early haven't had my coffee, but i am POSITIVE boot.img is NOT bootloader it is kernel )
> ...


You are correct. boot.img is kernel, bootloader.img is bootloader.

fastboot flash bootloader bootloader.img
fastboot flash boot boot.img


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## 808phoneaddict (Jul 6, 2012)

ashclepdia said:


> boot.img is the kernel not the bootloader
> the bootloader doesn't get backed up with a nandroid
> if you want to revert to ics bootloader, it's just a simple fastboot flash i do believe. but not of a boot.img
> for some reason i wanna say it's actually called "bootloader.img" (sorry it's early haven't had my coffee, but i am POSITIVE boot.img is NOT bootloader it is kernel )
> ...


LOL ok i was looking for a simple automated way of doing it, but i did install the fastboot into my comp and have gotten to it thru command prompt just because i wanted to follow along with some tutorial i was reading in case id ever have to do it manually...i downloaded it from that wiki link...its called bootloader-toro-primela03.img (for the 4.0.4) bootloader...thanks everyone for the support and quick responses...one last question...do i just fastboot it to my phone, and not worry about wiping the original one?? same question for uploading the jb bootloader...


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## blaineevans (Jul 11, 2011)

808phoneaddict said:


> LOL ok i was looking for a simple automated way of doing it, but i did install the fastboot into my comp and have gotten to it thru command prompt just because i wanted to follow along with some tutorial i was reading in case id ever have to do it manually...i downloaded it from that wiki link...its called bootloader-toro-primela03.img (for the 4.0.4) bootloader...thanks everyone for the support and quick responses...one last question...do i just fastboot it to my phone, and not worry about wiping the original one?? same question for uploading the jb bootloader...


It overwrites, you do not need to wipe it or anything of the sort.


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## JBirdVegas (Jun 11, 2011)

Boot loaders don't really need to change a heck of a lot they have a pretty static job meaning, especially in Android, allow interface for fast boot or boot kernel (Not a debate about locked bootloaders). For example all you linux junkies know how little grub has changed over the years, grub is a boot loader and is the same thing but embedded devices include the flashing interface instead of grub command line.

Almost all computers use a bootloader and are MOSTLY similar.


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## 808phoneaddict (Jul 6, 2012)

blaineevans said:


> It overwrites, you do not need to wipe it or anything of the sort.


Thanks again for your help! When I see/read about a stable rom for jelly bean, then I'll probably update to both! My current version (jelly belly 2.5) is good enough considering all the bugs in hearing about in 3.0 &3.1... Waiting for a good aosp rom!

Sent from my Galaxy Nexus using Tapatalk 2


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## Droidlovinyogi (Jul 4, 2011)

Great thread! Thanks to all involved for the discussion and education.


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## Raziel36 (Aug 14, 2011)

808phoneaddict said:


> Thanks again for your help! When I see/read about a stable rom for jelly bean, then I'll probably update to both! My current version (jelly belly 2.5) is good enough considering all the bugs in hearing about in 3.0 &3.1... Waiting for a good aosp rom!
> 
> Sent from my Galaxy Nexus using Tapatalk 2


http://download.peteralfonso.com/toro/rom
Bugless Beast by Pete. Full AOSP ROM. It's super slick/buttery and I've had zero problems with it. The boot time is ridiculously quick, too, compared to others. He's been one of my favorite devs since I had my OG Moto Droid.

Sent from my Galaxy Nexus using RootzWiki


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## 808phoneaddict (Jul 6, 2012)

Raziel36 said:


> http://download.peteralfonso.com/toro/rom
> Bugless Beast by Pete. Full AOSP ROM. It's super slick/buttery and I've had zero problems with it. The boot time is ridiculously quick, too, compared to others. He's been one of my favorite devs since I had my OG Moto Droid.
> 
> Sent from my Galaxy Nexus using RootzWiki


 I have a friend who's tried it, but for some reason came back to jelly belly, i might give it a shot later this weekend... Currently on jelly belly and im loving it!

Sent from my Galaxy Nexus using Tapatalk 2


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## android4temo (Dec 26, 2011)

Been trying to get this answer for a long while.... do I flash JB Bootloader after I have my Jelly Bean ROM and GApps installed?

Thanks!

Tapped or Swyped (depending on how lazy I'm feeling) on my Galaxy Nexus


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## yarly (Jun 22, 2011)

Using one or the other will have as much of an effect on what version of Android you run as doing a rain dance will have on the weather.


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## Shanp (Jun 25, 2011)

Could someone be kind enough to post a link to where the JB Bootloaders are so I can update it thanks.


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## poontab (Jun 7, 2011)

yarly said:


> Using one or the other will have as much of an effect on what version of Android you run as doing a rain dance will have on the weather.


That. 
Which bootloader is on your phone has no effect on Android. The bootloader isn't like an HTC h-boot so changing from one to another is a pointless exercise.


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## ERIFNOMI (Jun 30, 2011)

I went ahead and updated from the bootloader my phone came with, PRIMEKK15 (4.0.2). I know it's not going to make any difference but I'm bored.



Shanp said:


> Could someone be kind enough to post a link to where the JB Bootloaders are so I can update it thanks.


Peter Alfonso has a lot of stuff, including bootloaders. http://download.peteralfonso.com/toro


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## mssam (Feb 20, 2012)

RickRom said:


> You can find the ICS bootloader on Peter Alfonso's Bugless Beast site
> 
> http://download.peteralfonso.com/toro


One of the nice things about that site is you see that the 4.0.4 bootloader is PRIMELA03 and 4.1 is PRIMELC03. I don't think that info has been updated on the nexus wiki page yet. A few weeks ago when I originally flashed a zip for the jelly bean bootloader, the img in the zip was just labeled "bootloader.img" and I don't recall if flashing the jelly bean bootloader zip through recovery actually flashed the bootloader to PRIMELC03, but after looking at this thread, I took a close look at my bootloader. It's nice to know that if I have a jelly bean bootloader it should read PRIMELC03. I don't know how much of a difference it will make flashing back to ICS, but at the rate these developers are moving, I shouldn't have to flash back to ICS too many more times...


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## mueron2000 (Jul 22, 2012)

Can somebody please instruct me how to flash the jelly bean bootloader? I have fastboot and am running a jelly bean rom just not sure about commands.


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## RickRom (Jan 4, 2012)

Download the ZIP from the link on the previous page and flash it like a ROM.


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## ERIFNOMI (Jun 30, 2011)

Or extract the bootloader from the zip, reboot into the bootloader, and run "fastboot flash bootloader bootloader.img"

It should be noted that though this is being called "jelly bean bootloader" it has nothing to do with running jelly bean. It's just a name to coincide with the release it belongs to. Much like how radios are named 4.0.1, 4.0.2, etc., based on which OTA they were pulled from.


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## nybadboy11 (Mar 25, 2012)

iPois0n said:


> These are mine and contains the 4.0.4 radios as well as bootloader for ICS. I wouldn't recommend flashing this unless your radios are 4.0.2. Also I'm not responsible for anything that may happen to your device during or after flashing. http://db.tt/2XogNVXI


I DONT UNDERSTAND THIS BOOTLOADER STUFF HOW DO I KNOW WHICH I HAVE AND WHY WOULD I CHANGE IT ?


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## mssam (Feb 20, 2012)

Look at your bootloader. It will show you which version you have. Somebody correct me if I'm wrong, but if it says PRIMELA03, then you have the ics 4.0.4 bootloader. If it says PRIMELC03, then you have the jelly bean 4.1 bootloader.


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## Protonus (Aug 19, 2011)

ERIFNOMI said:


> Peter Alfonso has a lot of stuff, including bootloaders. http://download.peteralfonso.com/toro


Had a tricky time finding a thread with bootloaders, glad I found this one, thanks for the link.

The bootloaders there can be flashed just like a ROM from recovery. Worked great!


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## mrm43 (Jul 17, 2012)

Hi, i was glad i bump into this. Never new that ics and jelly have different bootloader. I am on jelly rom and have ics bootloader. 
Just wanted to ask if we should update to jelly bootloader. What are the advantages of having it on a jelly rom.

Sent from my Galaxy Nexus using Tapatalk 2


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## chefb (Sep 4, 2011)

mrm43 said:


> Hi, i was glad i bump into this. Never new that ics and jelly have different bootloader. I am on jelly rom and have ics bootloader.
> Just wanted to ask if we should update to jelly bootloader. What are the advantages of having it on a jelly rom.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


I have the same question... but no answer.. u have the jb boot loader.. an can't tell the difference! If I has anything to do with" boot time" then its bull excrement Cuz it takes just as long as the ICS!


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## cupfulloflol (Dec 15, 2011)

mrm43 said:


> Hi, i was glad i bump into this. Never new that ics and jelly have different bootloader. I am on jelly rom and have ics bootloader.
> Just wanted to ask if we should update to jelly bootloader. What are the advantages of having it on a jelly rom.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


There are no advantages or disadvantages to having the JB bootloader.


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## yarly (Jun 22, 2011)

mrm43 said:


> Hi, i was glad i bump into this. Never new that ics and jelly have different bootloader. I am on jelly rom and have ics bootloader.
> Just wanted to ask if we should update to jelly bootloader. What are the advantages of having it on a jelly rom.
> 
> Sent from my Galaxy Nexus using Tapatalk 2


http://rootzwiki.com/topic/29448-ics-bootloader-vs-jb-bootloader/page__st__30#entry831999


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