[Miscellaneous Android Development] dragonhustler:
Hey guys its me dragonhustler with an awesome tutorial.

In this tutorial i will guide you on how to dual boot your allwinner a10 device with multiple roms. AS i am writting this am currently dual booting stock ics rom with christian troy's aokp rom :). Anyways lets start.

Please know this i just figured out this method but one thing that will not work is dual booting cm10 with aokp. I tried that but touch wont work with cm10 but aokp is working perfectly. Another thing is that i dual booted from a usb not an sd card but am pretty sure it will work.

First Step [Partitioning Your Sd card or USB]

NOTE: Please know that i done this on a usb flash drive but am so sure it will work on an sd card.

First you need a spare usb flash drive or spare sdcard that you will use. I recommend they should be more than 4gb but i done mine on a 4gb usb flash drive so its stable.

On your pc download minitool partition manager from here ------> http://download.cnet.com/MiniTool-Partition-Wizard-Home-Edition/3000-2094_4-10962200.html

After that install everything correctly and then at the end click finish and launch minitool

When its loaded take your spare sdcard or usb flash drive and plug it in the pc

It will then be loaded into minitool

Right click on the usb or sdcard and choose delete. Yes delete thats why i said spare

After its deleted Right click on the unnalocated space and choose create

Now create 3 partitions EXT4 Partitions

system around 400 or 500 mb, data around 1500 mb and finnaly cache around 700 mb

After thats done all of them should be primary not logical.

Now thats done click apply and wait for the process to finish

When the process is done take the usb or sdcard and mount it on your allwinner a10 and go to the app store and download a programm partition table.

When its downloaded open it up and it will then tell you the partition names on the sdcard

Now you have to look carefully at the sizes so you dont get confused which one is which

I could tell mine because system was 510 mb, cache 540 mb and data was 1400 mb

it wont show the names but you will just know by the sizes

It will probably just show names like sda1 sda2 sda3

so just figure out which one is which and memorise or write them somewhere.

Building a Rom for Multi-boot [Boot.img]

You dont really have to build a rom from source all you have to do is customise it so that it boots from the sdcard you partitioned or the usb flash drive

Ok first take any custom rom you want to dual boot say this one -----> http://xdaforums.com/showthread.php?t=1821398

Now when its downloaded find any boot.img unpacking tools

Now you unpack the boot.img and then find the file init.sun4ei.rc [i think] the open it up with notepad++

After that find these lines:

mount ext4 /dev/block/nandd /system wait ro
mount ext4 /dev/block/nandxx /data wait noatime nosuid nodev
mount ext4 /dev/block/nandx /cache wait noatime nosuid nodev

Something like that and and it will tell you which one belongs to which as you can see

Now what you do is just replace those nandXX with the names you memorised earliear which. Then place the name for the system partition in the system partition like mine.

mount ext4 /dev/block/sd1 /system wait ro
mount ext4 /dev/block/sda3 /data wait noatime nosuid nodev
mount ext4 /dev/block/sda2 /cache wait noatime nosuid nodev

sda1, sda2 and sda3 are my codes for the partitions use yours not mine

When thats done just repack the boot.img and save it somewhere for later.

The rom [updater-script]

Now you have delt with the boot.img lets deal with the updater script of your rom

use any unzipping program and unzip meta inf folder in the rom you want to dual boot

Now open up the folder and then with notepad++ open updater script

Now all you have to do is edit where the mount partitions and format partitions for system are

If there are any other partitions like for bootloader just leave them

Now thats done

The rom [compatibility.zip]

open up compatibilty.zip and also extract the meta inf folder and do the same where it mounts for system. Just change the name at the end not all files like dev/block/XX

When thats done just replace the updater scripts of all files with your modded ones :D

Now thats done take your rom plug in your usb or sdcard boot into cwm and flash rom and after that you will boot into you new rom :)

For gapps just do the same in the updater script.

Credits Macadamia Daze