Dual Boot Atrix CM9 (emmc) and CM7 (sdcard)

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sendust7

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Oct 24, 2011
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Recently I became interested in dual booting my Atrix, mainly for the fun of it, and because I like the convenience of quickly reverting to a different ROM without having to restore it from backup. I would also like to evaluate the performance of my system with sdcard in the loop among other things.

From my web research, it appears that multiple attempts at dual booting the Atrix have been made without much success. I have heard of SafeStrap, but I'm the kind of person who wants to know what’s happening inside the black box. So I decided to try my hand by flashing CM9 to internal memory and CM7 to my Patriot 16GB Class 4 micro-SD card. I did all of this on Ubuntu 11.10 using GParted, Android SDK and several Perl and Bourne shell scripts that I either customized or created.

I probably could have done this on Windows (which for example has Atrix USB drivers whereas Ubuntu does not) and perhaps be able to use available space on my 10GB emmc to host additional ROMs. But in spite of the lack of drivers, I felt more comfortable having a full-up, dedicated *nix-based OS on hand to support the experiment.

I decided to to push a stable ROM to sdcard (in this case, CM7.2 RC1), one that runs well without any patches --- because a stock recovery tool wouldn't recognize it.

The experiment was successful as I now enjoy my 3GB CM7 build running from SD card with stable browser, keyboard and camera. And I can still use Joker's Kitchen Sink to explore some of the many possible ROM configurations without touching the CM7 build.

YouTube video (3:38) showing reboots from one ROM to the other: http://www.youtube.com/watch?v=31TPyAguQ60

Preliminaries (Ubuntu)

GParted and Perl installed

Android SDK for Linux (i386) installed http://developer.android.com/sdk/index.html

I download testsign.zip from http://xdaforums.com/showthread.php?t=551711 , copy to Ubuntu <android-sdk-linux/tools> directory and extract zip there. This creates a testsign subfolder with testsign.jar file inside.


Atrix Filesystem Analysis

I boot my phone to CWM 5.0.2.0, open an Ubuntu terminal, get root (sudo -s), run adb shell and invoke the “edify” and “df” commands to view the current filesystem:

~ # edify
recovery filesystem table
=========================
0 /tmp ramdisk (null) (null)
1 /boot emmc /dev/block/mmcblk0p11 (null)
2 /cache ext3 /dev/block/mmcblk0p15 (null)
3 /data ext3 /dev/block/mmcblk0p16 (null)
4 /sdcard vfat /dev/block/mmcblk1p1 (null)
5 /emmc vfat /dev/block/mmcblk0p18 (null)
6 /system ext3 /dev/block/mmcblk0p12 (null)
7 /recovery emmc /dev/block/mmcblk0p10 (null)
8 /osh ext3 /dev/block/mmcblk0p13 (null)
9 /preinstall ext3 /dev/block/mmcblk0p17 (null)

~ # df -a
Filesystem 1K-blocks Used Available Use% Mounted on
tmpfs 417804 32 417772 0% /dev
devpts 0 0 0 0% /dev/pts
proc 0 0 0 0% /proc
sysfs 0 0 0 0% /sys
/dev/block/mmcblk0p15 645056 69020 543268 11% /cache
/dev/block/mmcblk0p16 2064208 129052 1830300 7% /data
/dev/block/mmcblk0p12 322516 238496 84020 74% /system​

SD Card Partitioning

Next I get root on Ubuntu, connect SD card to PC, ensure SD card adapter switch is set to read/write, run GParted and shrink the vfat (fat32) partition to allow room for /system, /cache and /data in that order. Then I create these partitions as ext4 with sizes reasonably consistent with the existing filesystem on emmc.

Note: GParted did not see my internal (emmc) card, and it prefixed the sdcard partitions as “/dev/mmcblk0” instead of “/dev/mmcblk1”.

Now I exit GParted, pull sdcard from PC and reinsert into phone. Then I boot to CWM, connect phone to PC, enter adb shell and verify the new sdcard partition map using the onboard “parted” tool:

~ # parted /dev/block/mmcblk1

GNU Parted 1.8.8.1.179-aef3
Using /dev/block/mmcblk1
Welcome to GNU Parted! Type 'help' to view a list of commands.

(parted) print
Model: SD SU16G (sd/mmc)
Disk /dev/block/mmcblk1: 15.9GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 4194kB 10.7GB 10.7GB primary fat32 lba
2 10.7GB 11.1GB 346MB primary ext4
3 11.1GB 11.8GB 692MB primary ext4
4 11.8GB 14.0GB 2217MB primary ext4

quit
~#​

Clone CM7 to SD Card

Presently I have CM7.2 RC1 installed in emmc, and I want to clone this ROM to sdcard. But I first ensure that my phone is adequately charged, especially if I will be in CWM for a long time. My experience is that CWM can drain the battery, even when phone is connected to a powered USB hub.

I boot to CWM 5.0.2.0, open Ubuntu terminal on PC, get root (sudo -s), run adb shell and mount the new CM7 sdcard partitions.

Then I clone ROM to sdcard. (I did this over ADB, though in retrospect I probably could have done it more quickly with terminal emulator.)

~ # dd if=/dev/block/mmcblk0p12 of=/dev/block/mmcblk1p2
655360+0 records in
655360+0 records out
335544320 bytes (320.0MB) copied, 140.786369 seconds, 2.3MB/s

~ # dd if=/dev/block/mmcblk0p15 of=/dev/block/mmcblk1p3
1310720+0 records in
1310720+0 records out
671088640 bytes (640.0MB) copied, 282.791984 seconds, 2.3MB/s

~ # dd if=/dev/block/mmcblk0p16 of=/dev/block/mmcblk1p4
4194304+0 records in
4194304+0 records out
2147483648 bytes (2.0GB) copied, 898.662170 seconds, 2.3MB/s​

Since the data partition is fairly large, I ending up using the “cat” command, which cut the transfer time to about 6 minutes….

~ # cat /dev/block/mmcblk0p16 > /dev/block/mmcblk1p4​

Flash CM9 to Internal Memory

Now I push Joker CM9 beta 0.6.0 zip to sdcard and install via CWM...

root@ubuntu:~/Desktop# adb push beta-0.6.0-cm-9.0.0-RC0-olympus-UNOFFICIAL-signed.zip /sdcard/Download
1286 KB/s (125162795 bytes in 95.013s)
root@ubuntu:~/Desktop#​


Modify CM7 Ramdisk, Re-pack ROM Zip and Re-sign

Now I modify ramdisk in the CM7 boot.img to mount the sdcard /system, /cache and /data partitions at boot time. To help streamline the mod, I wrote custom Perl scripts based on the ones linked here:

http://android-dls.com/wiki/index.php?title=HOWTO:_Unpack,_Edit,_and_Re-Pack_Boot_Images

My Perl script “unpack-romzip.pl” actually starts with a baseline ROM, extracts boot.img and then p****s out kernel and ramdisk directory from boot.img. Here is the script in action...

root@ubuntu:~/Desktop# ./unpack-romzip.pl update-cm-7.2.0-RC1-olympus+gapps.zip

Extract boot.img from update-cm-7.2.0-RC1-olympus+gapps.zip
Archive: update-cm-7.2.0-RC1-olympus+gapps.zip
inflating: boot.img

Rename boot.img to update-cm-7.2.0-RC1-olympus+gapps.img

kernel written to update-cm-7.2.0-RC1-olympus+gapps.img-kernel
ramdisk written to update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk.cpio.gz

Extract ramdisk zip to directory: update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk
513 blocks

Delete intermediate file: update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk.cpio.gz​

Results...
-rw-r--r-- 1 root root 2574336 2012-05-03 19:12 update-cm-7.2.0-RC1-olympus+gapps.img-kernel
drwxr-xr-x 8 root root 4096 2012-05-03 19:12 update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk​

In this experiment, the only ramdisk file I will modify is init.olympus.rc: I do so by commenting out the /system, /cache and /data mount commands for the emmc partitions and creating equivalent mount commands for the sdcard partitions...

# mount ext4 /dev/block/mmcblk0p12 /system noatime nodiratime wait ro barrier=1
# mount ext4 /dev/block/mmcblk0p16 /data nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
# mount ext4 /dev/block/mmcblk0p15 /cache nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
mount ext4 /dev/block/mmcblk1p2 /system noatime nodiratime wait ro barrier=1
mount ext4 /dev/block/mmcblk1p4 /data nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
mount ext4 /dev/block/mmcblk1p3 /cache nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc​

Now I back out of ramdisk and run my other Perl script: repack-romzip.pl, which combines ramdisk and kernel to obtain a new boot image and then generates a repacked ROM zip. Here is the script in action...

root@ubuntu:~/Desktop# ./repack-romzip.pl update-cm-7.2.0-RC1-olympus+gapps.zip

Repack Android boot image from kernel file and ramdisk directory and roll into new ROM zip

Run cpio and gzip on ramdisk directory
514 blocks

Make boot image from kernel file and ramdisk cpio zip

Updated boot.img...
-rw-r--r-- 1 root root 2725888 2012-05-03 19:20 update-cm-7.2.0-RC1-olympus+gapps-repack.img

Copy update-cm-7.2.0-RC1-olympus+gapps.zip to update-cm-7.2.0-RC1-olympus+gapps-repack.zip

Add updated boot.img to update-cm-7.2.0-RC1-olympus+gapps-repack.zip
updating: boot.img
zip warning: Local Entry CRC does not match CD: boot.img
(deflated 0%)​

I am almost ready to re-sign my CM7 ROM zip. But I first need to modify its updater-script to mount /system to /dev/block/mmcblk1p2 (sdcard) instead of /dev/block/mmcblk0p12 (emmc). So I edit the updater-script and change:

format("ext4", "EMMC", "/dev/block/mmcblk0p12");
mount("ext4", "EMMC", "/dev/block/mmcblk0p12", "/system");​

to

format("ext4", "EMMC", "/dev/block/mmcblk1p2");
mount("ext4", "EMMC", "/dev/block/mmcblk1p2", "/system");​

Now I invoke the java command below to re-sign the CM7 zip:

root@ubuntu:~/Desktop# java -classpath ~/android-sdk-linux/tools/testsign/testsign.jar testsign update-cm-7.2.0-RC1-olympus+gapps-repack.zip update-cm-7.2.0-RC1-olympus+gapps-repack-signed.zip
root@ubuntu:~/Desktop# ls -ld *.zip
-rw-rw-r-- 1 robert robert 125162795 2012-05-03 18:05 beta-0.6.0-cm-9.0.0-RC0-olympus-UNOFFICIAL-signed.zip
-rw-r--r-- 1 root root 105000424 2012-05-03 19:23 update-cm-7.2.0-RC1-olympus+gapps-repack-signed.zip
-rw-r--r-- 1 root root 104987732 2012-05-03 19:20 update-cm-7.2.0-RC1-olympus+gapps-repack.zip
-rw------- 1 robert robert 104999357 2012-05-01 20:10 update-cm-7.2.0-RC1-olympus+gapps.zip​

Then I transfer the re-signed zip to sdcard/Download, reboot to CWM and install.


Test Results

I do some preliminary testing by attempting to boot CM9 from Joker's CM9 1.0GHz v4 boot image file:

root@ubuntu:~/Desktop# fastboot boot cm9-1.0-atrixv4-boot.img
downloading 'boot.img'...
OKAY [ 0.204s]
booting...
OKAY [ 0.002s]
finished. total time: 0.206s​

Success. Now I try CM7...

root@ubuntu:~/Desktop# fastboot boot update-cm-7.2.0-RC1-olympus+gapps-repack.img
downloading 'boot.img'...
OKAY [ 0.182s]
booting...
OKAY [ 0.002s]
finished. total time: 0.185s​

And to my delight, CM7 boots :D

Finally I install Script Manager and push my custom boot-rom.sh to sdcard/Boot. This script offers four options: Current ROM (default), CM9, CM7 or CWM recovery. Rebooting to the other ROM is just a few keystrokes away, though I must configure Script Manager to run boot-rom.sh as superuser (press SU button on configuration screen).

2012.05.08-17.03.10.jpeg
2012.05.08-17.01.40.jpeg


Elapsed times…

Execution of boot-rom.sh on CM7 to CM9 welcome screen: 44 sec.
Execution of boot-rom.sh on CM9 to CM7 welcome screen: 45 sec.


Conclusions and Thoughts

My Atrix dual boot capability offers an efficient means to circumvent instabilities in CM9 by providing a stable CM7 ROM to run from my sdcard. Of course there are limitations here in that a stock recovery won't recognize my CM7 build. But I'm fine with that since I probably won't patch.

I think it would be kind of interesting to push identical ROMs on emmc and sdcard and compare performance. I heard from a fellow engineer that Class 16 cards are now available.

It would also be interesting to explore refinements like multiple-boot from emmc and various forms of automation.

This is a work in progress and I appreciate your constructive feedback. :)

YouTube video (3:38) showing reboots from one ROM to the other: http://www.youtube.com/watch?v=31TPyAguQ60

Credits

jokersax11 @ xda, ghost_og @ xda,
Photon Dev Team, Atrix Dev Team
Koush
Other credits embedded in this post
 

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F

fl1p1slander

Senior Member
Feb 15, 2012
89
21
Wow thanks for the info. I wanted to give this a try but I had a question. If I partition my sdcard to the specs you provided, can I flash your resigned cm7 zip and it would flash it to my sdcard. If that is possible, could you post the modified cm7?
 
ATRIXXIRTA

ATRIXXIRTA

Senior Member
Mar 17, 2012
2,434
768
The Shangri-La Motel
I think you better get into developing roms, because it sounds like you have an amazing amount of knowledge with this technology. Something I can only hope to achieve, lol.

I think you should make a full length 45 min youtube clip to explain everything, but I know that's not gonna happen, so see how much you can cram into 5 minutes! lol

Nice job man, outstanding progression!
 
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kingme__hu

kingme__hu

Senior Member
May 30, 2011
105
59
HangZhou
kingme.duapp.com
#!/system/bin/sh
mount -o remount,rw /dev/block/mmcblk0p1 /system//挂载/system为可写
busybox md5sum -cs /system/boot/md5 && CHANGE=0 || CHANGE=1//判断boot.img是否更新
echo $CHANGE
if [ "$CHANGE" = "1" ]
then
cat /dev/block/mmcblk0p5 > /data/boot1.img
busybox md5sum /system/build.prop > /system/boot/md5
echo "Creat new boot done!"
fi
if [ -e /data/boot2.img ]//判断另外的系统是否更新boot.img
then
busybox mv /data/boot2.img /system/boot/boot2.img
echo "Backup new boot done!"
fi
cat /system/boot/boot2.img > /dev/block/mmcblk0p5
fdisk /dev/block/mmcblk0 < /system/bin/fdisk1.sh
///////////////////同fixuid
mkdir /data/lib
chmod 0777 /data/lib
cat /data/system/packages.xml | grep 'package name="'| awk -F"\"" '{print $2}' > /data/packages.list
awk -F" " '{print "rm /data/data/"$1"/lib"}' /data/packages.list > /data/cx.sh
cat /system/bin/noshare|while read fname
do
echo "rm $fname-2/lib" >>/data/cx.sh
done
awk -F" " '{print "mkdir /data/lib/"$1}' /data/packages.list >> /data/cx.sh
awk -F" " '{print "mv /data/data/"$1"/lib/ /data/lib/"$1"/"}' /data/packages.list >> /data/cx.sh
busybox chown -R 1000.1000 /data/lib
awk -F" " '{print "rm -R /data/data/"$1"/lib"}' /data/packages.list >> /data/cx.sh
cat /system/bin/noshare|while read fname
do
echo "rm -R $fname-2/lib" >>/data/cx.sh
done
chmod 0777 /data/cx.sh
/data/cx.sh
////////////////////////////////////////////////////移动第二系统数据为主数据
cat /system/bin/noshare|while read fname
do
mv $fname "$fname-1"
mv "$fname-2" $fname
done
cat /data/noshare|while read fname//移动不需要共享的数据
do
mv $fname "$fname-1"
mv "$fname-2" $fname
done
echo "Move data done!"
/////////////////////////同fixuid
awk -F" " '{print "ln -s /data/lib/"$1" /data/data/"$1"/lib"}' /data/packages.list > /data/cx.sh
cat /data/system/packages.xml | grep 'package name=\"'| awk -F"\"" '{print $2" "$18}' | awk -F" " '{print "busybox chown -R "$2"."$2" /data/data/"$1}' >> /data/cx.sh
chmod 0777 /data/cx.sh
/data/cx.sh
echo "Move UID done!"
reboot
 
syngamer96

syngamer96

Senior Member
Feb 4, 2011
255
61
Singapore
kingme__hu said:
#!/system/bin/sh
mount -o remount,rw /dev/block/mmcblk0p1 /system//挂载/system为可写
busybox md5sum -cs /system/boot/md5 && CHANGE=0 || CHANGE=1//判断boot.img是否更新
echo $CHANGE
if [ "$CHANGE" = "1" ]
then
cat /dev/block/mmcblk0p5 > /data/boot1.img
busybox md5sum /system/build.prop > /system/boot/md5
echo "Creat new boot done!"
fi
if [ -e /data/boot2.img ]//判断另外的系统是否更新boot.img
then
busybox mv /data/boot2.img /system/boot/boot2.img
echo "Backup new boot done!"
fi
cat /system/boot/boot2.img > /dev/block/mmcblk0p5
fdisk /dev/block/mmcblk0 < /system/bin/fdisk1.sh
///////////////////同fixuid
mkdir /data/lib
chmod 0777 /data/lib
cat /data/system/packages.xml | grep 'package name="'| awk -F"\"" '{print $2}' > /data/packages.list
awk -F" " '{print "rm /data/data/"$1"/lib"}' /data/packages.list > /data/cx.sh
cat /system/bin/noshare|while read fname
do
echo "rm $fname-2/lib" >>/data/cx.sh
done
awk -F" " '{print "mkdir /data/lib/"$1}' /data/packages.list >> /data/cx.sh
awk -F" " '{print "mv /data/data/"$1"/lib/ /data/lib/"$1"/"}' /data/packages.list >> /data/cx.sh
busybox chown -R 1000.1000 /data/lib
awk -F" " '{print "rm -R /data/data/"$1"/lib"}' /data/packages.list >> /data/cx.sh
cat /system/bin/noshare|while read fname
do
echo "rm -R $fname-2/lib" >>/data/cx.sh
done
chmod 0777 /data/cx.sh
/data/cx.sh
////////////////////////////////////////////////////移动第二系统数据为主数据
cat /system/bin/noshare|while read fname
do
mv $fname "$fname-1"
mv "$fname-2" $fname
done
cat /data/noshare|while read fname//移动不需要共享的数据
do
mv $fname "$fname-1"
mv "$fname-2" $fname
done
echo "Move data done!"
/////////////////////////同fixuid
awk -F" " '{print "ln -s /data/lib/"$1" /data/data/"$1"/lib"}' /data/packages.list > /data/cx.sh
cat /data/system/packages.xml | grep 'package name=\"'| awk -F"\"" '{print $2" "$18}' | awk -F" " '{print "busybox chown -R "$2"."$2" /data/data/"$1}' >> /data/cx.sh
chmod 0777 /data/cx.sh
/data/cx.sh
echo "Move UID done!"
reboot
Click to expand...
Click to collapse

What's this? I don't... I... can't comprehend...
Anyone able to make an auto script to help beginners and confused people like me? I can't follow through half of the OP's instructions.... not used to using SDK and terminal/ADB.
 
djluis48

djluis48

Senior Member
Nov 16, 2009
1,773
232
Santo Domingo
Woooow!! This is epic dude! I could have a Blur rom on my sd and a custom rom on my internal, to keep webtop functionality when i want! A Windows guide would be prettt awesome! :p

Sent from my MB860 using XDA
 
Notorious544d

Notorious544d

Senior Member
Aug 18, 2011
2,104
2,370
London
Amazing!

This is amazing!! Thanks a lot for your work!

This could make things MUCH easier for me when testing both CM9 and CM7 Neutrino.

I hope this project matures by the time my exams finish, like as Jokersax11 said, the ability to save dalvik cache would be awesome.

Massive thumbs up from me here :D
 
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TheSmokingAndroid

TheSmokingAndroid

Senior Member
Apr 2, 2010
670
626
Victoria
This really is some fantastic development! I am beyond impressed. You my friend should join the league of developer jedi's.

Fantastic work!

Now, if this could only somehow be transformed into a zip...LOL
 
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tasadar

tasadar

Senior Member
Sep 11, 2007
134
18
J-Roc said:
This really is some fantastic development! I am beyond impressed. You my friend should join the league of developer jedi's.

Fantastic work!

Now, if this could only somehow be transformed into a zip...LOL
Click to expand...
Click to collapse

+1 for the ZIP and making this easier to use for the Ordinary good people like Some of Us :)

Amazing work ! Keep up
 
hatefuel19

hatefuel19

Senior Member
Sep 23, 2010
313
113
Lex
Thanks to your guide I've made it to cloning to sdcard all with windows. Will post back with tutorial if I can finish the job. Thank you for your amazing work!
 
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K

KH_Lionheart

Senior Member
Sep 25, 2011
135
42
Central Texas
Dude, you're awesome. I think this is the final little push I needed to get me computer set up to dual boot Ubuntu and windows definitely going to be worth it now. Thanks for the work
 
S

sendust7

Senior Member
Oct 24, 2011
348
810
California
J-Roc said:
This really is some fantastic development! I am beyond impressed. You my friend should join the league of developer jedi's.

Fantastic work!

Now, if this could only somehow be transformed into a zip...LOL
Click to expand...
Click to collapse

tasadar said:
+1 for the ZIP and making this easier to use for the Ordinary good people like Some of Us :)

Amazing work ! Keep up
Click to expand...
Click to collapse

Here's the problem: I needed GApps on CM7 to provide the tools needed to support my experiment. However, Google has requested that copyrighted material be removed from CM7. So while I was able to streamline the integration of GApps with CM7, I could not provide the ROM, only the procedure. See http://xdaforums.com/showthread.php?p=25588129#post25588129.

IDK, maybe Google will soften up a bit...? ;)
 
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    sendust7
    Recently I became interested in dual booting my Atrix, mainly for the fun of it, and because I like the convenience of quickly reverting to a different ROM without having to restore it from backup. I would also like to evaluate the performance of my system with sdcard in the loop among other things.

    From my web research, it appears that multiple attempts at dual booting the Atrix have been made without much success. I have heard of SafeStrap, but I'm the kind of person who wants to know what’s happening inside the black box. So I decided to try my hand by flashing CM9 to internal memory and CM7 to my Patriot 16GB Class 4 micro-SD card. I did all of this on Ubuntu 11.10 using GParted, Android SDK and several Perl and Bourne shell scripts that I either customized or created.

    I probably could have done this on Windows (which for example has Atrix USB drivers whereas Ubuntu does not) and perhaps be able to use available space on my 10GB emmc to host additional ROMs. But in spite of the lack of drivers, I felt more comfortable having a full-up, dedicated *nix-based OS on hand to support the experiment.

    I decided to to push a stable ROM to sdcard (in this case, CM7.2 RC1), one that runs well without any patches --- because a stock recovery tool wouldn't recognize it.

    The experiment was successful as I now enjoy my 3GB CM7 build running from SD card with stable browser, keyboard and camera. And I can still use Joker's Kitchen Sink to explore some of the many possible ROM configurations without touching the CM7 build.

    YouTube video (3:38) showing reboots from one ROM to the other: http://www.youtube.com/watch?v=31TPyAguQ60

    Preliminaries (Ubuntu)

    GParted and Perl installed

    Android SDK for Linux (i386) installed http://developer.android.com/sdk/index.html

    I download testsign.zip from http://xdaforums.com/showthread.php?t=551711 , copy to Ubuntu <android-sdk-linux/tools> directory and extract zip there. This creates a testsign subfolder with testsign.jar file inside.


    Atrix Filesystem Analysis

    I boot my phone to CWM 5.0.2.0, open an Ubuntu terminal, get root (sudo -s), run adb shell and invoke the “edify” and “df” commands to view the current filesystem:

    ~ # edify
    recovery filesystem table
    =========================
    0 /tmp ramdisk (null) (null)
    1 /boot emmc /dev/block/mmcblk0p11 (null)
    2 /cache ext3 /dev/block/mmcblk0p15 (null)
    3 /data ext3 /dev/block/mmcblk0p16 (null)
    4 /sdcard vfat /dev/block/mmcblk1p1 (null)
    5 /emmc vfat /dev/block/mmcblk0p18 (null)
    6 /system ext3 /dev/block/mmcblk0p12 (null)
    7 /recovery emmc /dev/block/mmcblk0p10 (null)
    8 /osh ext3 /dev/block/mmcblk0p13 (null)
    9 /preinstall ext3 /dev/block/mmcblk0p17 (null)

    ~ # df -a
    Filesystem 1K-blocks Used Available Use% Mounted on
    tmpfs 417804 32 417772 0% /dev
    devpts 0 0 0 0% /dev/pts
    proc 0 0 0 0% /proc
    sysfs 0 0 0 0% /sys
    /dev/block/mmcblk0p15 645056 69020 543268 11% /cache
    /dev/block/mmcblk0p16 2064208 129052 1830300 7% /data
    /dev/block/mmcblk0p12 322516 238496 84020 74% /system​

    SD Card Partitioning

    Next I get root on Ubuntu, connect SD card to PC, ensure SD card adapter switch is set to read/write, run GParted and shrink the vfat (fat32) partition to allow room for /system, /cache and /data in that order. Then I create these partitions as ext4 with sizes reasonably consistent with the existing filesystem on emmc.

    Note: GParted did not see my internal (emmc) card, and it prefixed the sdcard partitions as “/dev/mmcblk0” instead of “/dev/mmcblk1”.

    Now I exit GParted, pull sdcard from PC and reinsert into phone. Then I boot to CWM, connect phone to PC, enter adb shell and verify the new sdcard partition map using the onboard “parted” tool:

    ~ # parted /dev/block/mmcblk1

    GNU Parted 1.8.8.1.179-aef3
    Using /dev/block/mmcblk1
    Welcome to GNU Parted! Type 'help' to view a list of commands.

    (parted) print
    Model: SD SU16G (sd/mmc)
    Disk /dev/block/mmcblk1: 15.9GB
    Sector size (logical/physical): 512B/512B
    Partition Table: msdos

    Number Start End Size Type File system Flags
    1 4194kB 10.7GB 10.7GB primary fat32 lba
    2 10.7GB 11.1GB 346MB primary ext4
    3 11.1GB 11.8GB 692MB primary ext4
    4 11.8GB 14.0GB 2217MB primary ext4

    quit
    ~#​

    Clone CM7 to SD Card

    Presently I have CM7.2 RC1 installed in emmc, and I want to clone this ROM to sdcard. But I first ensure that my phone is adequately charged, especially if I will be in CWM for a long time. My experience is that CWM can drain the battery, even when phone is connected to a powered USB hub.

    I boot to CWM 5.0.2.0, open Ubuntu terminal on PC, get root (sudo -s), run adb shell and mount the new CM7 sdcard partitions.

    Then I clone ROM to sdcard. (I did this over ADB, though in retrospect I probably could have done it more quickly with terminal emulator.)

    ~ # dd if=/dev/block/mmcblk0p12 of=/dev/block/mmcblk1p2
    655360+0 records in
    655360+0 records out
    335544320 bytes (320.0MB) copied, 140.786369 seconds, 2.3MB/s

    ~ # dd if=/dev/block/mmcblk0p15 of=/dev/block/mmcblk1p3
    1310720+0 records in
    1310720+0 records out
    671088640 bytes (640.0MB) copied, 282.791984 seconds, 2.3MB/s

    ~ # dd if=/dev/block/mmcblk0p16 of=/dev/block/mmcblk1p4
    4194304+0 records in
    4194304+0 records out
    2147483648 bytes (2.0GB) copied, 898.662170 seconds, 2.3MB/s​

    Since the data partition is fairly large, I ending up using the “cat” command, which cut the transfer time to about 6 minutes….

    ~ # cat /dev/block/mmcblk0p16 > /dev/block/mmcblk1p4​

    Flash CM9 to Internal Memory

    Now I push Joker CM9 beta 0.6.0 zip to sdcard and install via CWM...

    root@ubuntu:~/Desktop# adb push beta-0.6.0-cm-9.0.0-RC0-olympus-UNOFFICIAL-signed.zip /sdcard/Download
    1286 KB/s (125162795 bytes in 95.013s)
    root@ubuntu:~/Desktop#​


    Modify CM7 Ramdisk, Re-pack ROM Zip and Re-sign

    Now I modify ramdisk in the CM7 boot.img to mount the sdcard /system, /cache and /data partitions at boot time. To help streamline the mod, I wrote custom Perl scripts based on the ones linked here:

    http://android-dls.com/wiki/index.php?title=HOWTO:_Unpack,_Edit,_and_Re-Pack_Boot_Images

    My Perl script “unpack-romzip.pl” actually starts with a baseline ROM, extracts boot.img and then p****s out kernel and ramdisk directory from boot.img. Here is the script in action...

    root@ubuntu:~/Desktop# ./unpack-romzip.pl update-cm-7.2.0-RC1-olympus+gapps.zip

    Extract boot.img from update-cm-7.2.0-RC1-olympus+gapps.zip
    Archive: update-cm-7.2.0-RC1-olympus+gapps.zip
    inflating: boot.img

    Rename boot.img to update-cm-7.2.0-RC1-olympus+gapps.img

    kernel written to update-cm-7.2.0-RC1-olympus+gapps.img-kernel
    ramdisk written to update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk.cpio.gz

    Extract ramdisk zip to directory: update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk
    513 blocks

    Delete intermediate file: update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk.cpio.gz​

    Results...
    -rw-r--r-- 1 root root 2574336 2012-05-03 19:12 update-cm-7.2.0-RC1-olympus+gapps.img-kernel
    drwxr-xr-x 8 root root 4096 2012-05-03 19:12 update-cm-7.2.0-RC1-olympus+gapps.img-ramdisk​

    In this experiment, the only ramdisk file I will modify is init.olympus.rc: I do so by commenting out the /system, /cache and /data mount commands for the emmc partitions and creating equivalent mount commands for the sdcard partitions...

    # mount ext4 /dev/block/mmcblk0p12 /system noatime nodiratime wait ro barrier=1
    # mount ext4 /dev/block/mmcblk0p16 /data nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
    # mount ext4 /dev/block/mmcblk0p15 /cache nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
    mount ext4 /dev/block/mmcblk1p2 /system noatime nodiratime wait ro barrier=1
    mount ext4 /dev/block/mmcblk1p4 /data nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc
    mount ext4 /dev/block/mmcblk1p3 /cache nosuid nodev noatime nodiratime wait barrier=1 noauto_da_alloc​

    Now I back out of ramdisk and run my other Perl script: repack-romzip.pl, which combines ramdisk and kernel to obtain a new boot image and then generates a repacked ROM zip. Here is the script in action...

    root@ubuntu:~/Desktop# ./repack-romzip.pl update-cm-7.2.0-RC1-olympus+gapps.zip

    Repack Android boot image from kernel file and ramdisk directory and roll into new ROM zip

    Run cpio and gzip on ramdisk directory
    514 blocks

    Make boot image from kernel file and ramdisk cpio zip

    Updated boot.img...
    -rw-r--r-- 1 root root 2725888 2012-05-03 19:20 update-cm-7.2.0-RC1-olympus+gapps-repack.img

    Copy update-cm-7.2.0-RC1-olympus+gapps.zip to update-cm-7.2.0-RC1-olympus+gapps-repack.zip

    Add updated boot.img to update-cm-7.2.0-RC1-olympus+gapps-repack.zip
    updating: boot.img
    zip warning: Local Entry CRC does not match CD: boot.img
    (deflated 0%)​

    I am almost ready to re-sign my CM7 ROM zip. But I first need to modify its updater-script to mount /system to /dev/block/mmcblk1p2 (sdcard) instead of /dev/block/mmcblk0p12 (emmc). So I edit the updater-script and change:

    format("ext4", "EMMC", "/dev/block/mmcblk0p12");
    mount("ext4", "EMMC", "/dev/block/mmcblk0p12", "/system");​

    to

    format("ext4", "EMMC", "/dev/block/mmcblk1p2");
    mount("ext4", "EMMC", "/dev/block/mmcblk1p2", "/system");​

    Now I invoke the java command below to re-sign the CM7 zip:

    root@ubuntu:~/Desktop# java -classpath ~/android-sdk-linux/tools/testsign/testsign.jar testsign update-cm-7.2.0-RC1-olympus+gapps-repack.zip update-cm-7.2.0-RC1-olympus+gapps-repack-signed.zip
    root@ubuntu:~/Desktop# ls -ld *.zip
    -rw-rw-r-- 1 robert robert 125162795 2012-05-03 18:05 beta-0.6.0-cm-9.0.0-RC0-olympus-UNOFFICIAL-signed.zip
    -rw-r--r-- 1 root root 105000424 2012-05-03 19:23 update-cm-7.2.0-RC1-olympus+gapps-repack-signed.zip
    -rw-r--r-- 1 root root 104987732 2012-05-03 19:20 update-cm-7.2.0-RC1-olympus+gapps-repack.zip
    -rw------- 1 robert robert 104999357 2012-05-01 20:10 update-cm-7.2.0-RC1-olympus+gapps.zip​

    Then I transfer the re-signed zip to sdcard/Download, reboot to CWM and install.


    Test Results

    I do some preliminary testing by attempting to boot CM9 from Joker's CM9 1.0GHz v4 boot image file:

    root@ubuntu:~/Desktop# fastboot boot cm9-1.0-atrixv4-boot.img
    downloading 'boot.img'...
    OKAY [ 0.204s]
    booting...
    OKAY [ 0.002s]
    finished. total time: 0.206s​

    Success. Now I try CM7...

    root@ubuntu:~/Desktop# fastboot boot update-cm-7.2.0-RC1-olympus+gapps-repack.img
    downloading 'boot.img'...
    OKAY [ 0.182s]
    booting...
    OKAY [ 0.002s]
    finished. total time: 0.185s​

    And to my delight, CM7 boots :D

    Finally I install Script Manager and push my custom boot-rom.sh to sdcard/Boot. This script offers four options: Current ROM (default), CM9, CM7 or CWM recovery. Rebooting to the other ROM is just a few keystrokes away, though I must configure Script Manager to run boot-rom.sh as superuser (press SU button on configuration screen).

    2012.05.08-17.03.10.jpeg
    2012.05.08-17.01.40.jpeg


    Elapsed times…

    Execution of boot-rom.sh on CM7 to CM9 welcome screen: 44 sec.
    Execution of boot-rom.sh on CM9 to CM7 welcome screen: 45 sec.


    Conclusions and Thoughts

    My Atrix dual boot capability offers an efficient means to circumvent instabilities in CM9 by providing a stable CM7 ROM to run from my sdcard. Of course there are limitations here in that a stock recovery won't recognize my CM7 build. But I'm fine with that since I probably won't patch.

    I think it would be kind of interesting to push identical ROMs on emmc and sdcard and compare performance. I heard from a fellow engineer that Class 16 cards are now available.

    It would also be interesting to explore refinements like multiple-boot from emmc and various forms of automation.

    This is a work in progress and I appreciate your constructive feedback. :)

    YouTube video (3:38) showing reboots from one ROM to the other: http://www.youtube.com/watch?v=31TPyAguQ60

    Credits

    jokersax11 @ xda, ghost_og @ xda,
    Photon Dev Team, Atrix Dev Team
    Koush
    Other credits embedded in this post
    View
    4
    S
    sendust7
    YouTube video (3:38) demonstrating reboot from one ROM to the other: http://www.youtube.com/watch?v=31TPyAguQ60
    View
    3
    A
    aaron.a
    Holy. ****.

    Sent from my MB860 using XDA
    View
    3
    jokersax11
    jokersax11
    Something you could look into is moving the apps to SD and let each rom build its own dalvik cache. Then you can keep your apps between both builds

    Sent from my MB855 using XDA
    View
    2
    hatefuel19
    hatefuel19
    windoze style

    EDIT: go here for windows guide

    http://xdaforums.com/showthread.php?t=1645664
    View

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