Database Users

developing for the DSTL1 / N21

I want to try developing for the DSTL1 / N21
There are quite a few interesting things we can do...
Success has been been seen by xda-devs such as JesusFreke, Amon_RA, Haykuro, and Cyanogen (yes there others) in the field of Android ROMs. The ground work is there, porting and developing can commence.
Why do this?
Current ROM 1.5 - has many problems...
Unofficial ROM 1.6 - is a GREAT improvement, but makes one hungry for something better...
It would be awesome to have some success in this field. I know this device is capable of so much more, but I believe the implementation of the system is the issue. This is not the phone developers fault, as they have their own company agenda, but we could improve our own performance and satisfaction .
For example, my device (1.6 rooted) lags with having only ~50% CPU utilization and ~50MB RAM free...
Overclocking (i mean forcing full CPU capacity - 624Mhz) the CPU has barely helped and only aided battery drain...
Relevant comparison of G1 vs DSTL1 (N21) are
RAM - G1: 192MB vs DSTL1: 128MB
CPU - G1: 528Mhz vs DSTL1: 624Mhz
These specification comparisons say that G1 can run a better ROM than DSTL1? I don't think so. DSTL1 only loses in RAM, which can be made up for using swap!
Devs had success with techniques using: App2SD, swap, ext3, and BFS (faster file system). I believe we could do something impressive here! There are pros and cons to this.
Developers and Testers would be needed. A team of 5 developers and a few testers should be able to get us on the right track. We would definitely need Linux experience, or the desire and ability to soak up all the info on Google
A Linux kernel is a must for this phone, we would have to compile our own... It would be nice to preserve DUAL SIM, but in reality we might have to give up this luxury, as it is proprietary code, unless a new ROM is made backwards compatible (which is possible).
Cyanogen's Github is available for knowledge osmosis http://github.com/cyanogen
A DSTL1 Recovery by Amon_RA (based on Cyanogen's Recovery) is already in Beta...
Cool things are possible. Could I find some developers willing to donate their free time?
Please limit responses to dev talk.

reserved for later

crzyruski,
Believe it or not the very luxury you talk about giving up(dual sim) is the reason why may of us bother to buy these phones(DSTL1\N21) in the first place. Other wise we might as well go with a mainstream phone such as hero etc.

chrismotto said:
crzyruski,
Believe it or not the very luxury you talk about giving up(dual sim) is the reason why may of us bother to buy these phones(DSTL1\N21) in the first place. Other wise we might as well go with a mainstream phone such as hero etc.
Click to expand...
Click to collapse
Its a possibility that I'm not going to ignore, so I stated it.
The point is that the current OS is lacking. Initially we would want to port and learn from porting of the quality ROMs available now. Those obviously don't support dual-SIM.
Progress needs to start from somewhere. When someone releases a new port or ROM not all pieces work... look at the Eclair (2.0) port, half the features don't work!
If enough heads came together we could probably retain dual-SIM, common this is linux and I've seen the most amazing development come to realization. I just need the teamwork because it might take me a whole year in my spare time...

Having a kernel working
Hi,
the most important IMHO is having a kernel working, built from sources.
Obviously, some closed source drivers must be rewritten, notably the NXP5209 (the GSM modem), if we want the device to be useful (i.e. if we want to make phone call).
My first attempt of booting with a custom kernel was unsucessfull (black screen), which brings to the second point: the lack of some sort of console for kernel debuging.
Any idea regarding the NXP? Anyone is aware of some opensource driver or specs?
Any idea also regarding kernel debugging in the N21/DSTL1?
sfabris

@sfabris
I will try to find info for the questions you have.
My initial work will be to make an emulator so we can test on PC and not our devices (because we need them functional for every day life )
Have you checked out how other modders have done kernel modifications?
Namely JF and Cyanogen?
I can't begin to comprehend so I'm glad you took the initiative with this.
Lets make some progress

sfabris said:
Obviously, some closed source drivers must be rewritten, notably the NXP5209 (the GSM modem), if we want the device to be useful (i.e. if we want to make phone call).
Any idea regarding the NXP? Anyone is aware of some opensource driver or specs?
Click to expand...
Click to collapse
Maybe we have it all wrong???? Maybe its PNX?
PDA DB reports DSTL1 as having Nexperia PNX5209 (ARM946) Phone Controller.
http://pdadb.net/index.php?m=specs&id=1714&view=1&c=general_mobile_dstl1
A similar Android with this phone controller is WayteQ X-Phone (TechFaith Lancer)
http://pdadb.net/index.php?m=specs&id=1801&view=1&c=wayteq_x-phone_android_techfaith_lancer

crzyruski said:
@sfabris
Have you checked out how other modders have done kernel modifications?
Namely JF and Cyanogen?
I can't begin to comprehend so I'm glad you took the initiative with this.
Lets make some progress
Click to expand...
Click to collapse
As I'm forced to HTC G1 until I'll wait the replacement for my N21 I'll go in detail on the kernel boot process on other hardware.
A fast way to test kernel in our every day device is kexec which should work also on ARM.

sfabris said:
A fast way to test kernel in our every day device is kexec which should work also on ARM.
Click to expand...
Click to collapse
As far as I understand, kexec is a program that can run a new kernel on the fly...
So I could try a new kernel right from my device without reflashing?
have you tried this? Or is this still theory?

crzyruski said:
As far as I understand, kexec is a program that can run a new kernel on the fly...
So I could try a new kernel right from my device without reflashing?
have you tried this? Or is this still theory?
Click to expand...
Click to collapse
I've tried it on x86, never on arm.
Support is there also for arm, but this not imply that also the Marvell PXA is supported.
It's basically the same way of booting Android from WM via haret.
Fastest way to boot your new kernel or to crash your machine

I have created an emulator.
FYI, LCD density should be 120.
Edit: Technically the density is 133...

files prevent recovery-RA-DSTL1-v1.2.3 from loading
I have been wrestling with the beta recovery-RA-DSTL1-v1.2.3
Amon_RA retrofitted his own recovery image to work for the DSTL1 (N21)...
IT HAS AWESOME POTENTIAL.
Currently ADB RECOVERY SHELL + ROOT is the only thing that is functional.
But I haven't been able to get in touch with him to continue work on it.
The following files prevent me from booting into RA's Recovery, so I remove them:
- e2fsck
- mke2fs
- parted
- tune2fs
Once I am in ADB RECOVERY SHELL I can push them back on and do what I need to do.
Unfortunately the changes are persistent so if I were to reboot and try Recovery Mode again, it won't load
What is so special about those four programs that prevent my recovery from loading?????

is there any ways to update the firmware of N21
hi,
i'm just buy a sciphone n21 (actually is already in our office for 2 weeks but find it now:-( )
and i've to face myself in a situation that i can't use this phone:-( since i buy this phone because:
- i assume that google apps auto sync contact and calendars. unfortunately this phone has not google apps by default.
- and has dual sim support.
so my question: is there any way to upgrade it to a firmware which support is?
can i do anything to use my phone?
thanks in advance.
regards.

crzyruski said:
I have been wrestling with the beta recovery-RA-DSTL1-v1.2.3
Amon_RA retrofitted his own recovery image to work for the DSTL1 (N21)...
IT HAS AWESOME POTENTIAL.
Currently ADB RECOVERY SHELL + ROOT is the only thing that is functional.
But I haven't been able to get in touch with him to continue work on it.
The following files prevent me from booting into RA's Recovery, so I remove them:
- e2fsck
- mke2fs
- parted
- tune2fs
Once I am in ADB RECOVERY SHELL I can push them back on and do what I need to do.
Unfortunately the changes are persistent so if I were to reboot and try Recovery Mode again, it won't load
What is so special about those four programs that prevent my recovery from loading?????
Click to expand...
Click to collapse
e2fsck is a filesystem check utility for ext2
mke2fs is for ext2 filesystem creation
parted is a partitioning tool
tune2fs is for change some filesystem parameters (usually checking interval)
I've read that recovery from Amon-Ra creates automatically 3 partitions (ext2, swap and FAT32). So those commands whould probably mean ext2 filesystem creation. I'm sure Amon-Ra could give us more information on this subject because he added them to the image.
Have you checked your SD card?.
PD: I'm waiting for my N21 . So I can't test yet.

andferno said:
e2fsck is a filesystem check utility for ext2
mke2fs is for ext2 filesystem creation
parted is a partitioning tool
tune2fs is for change some filesystem parameters (usually checking interval)
I've read that recovery from Amon-Ra creates automatically 3 partitions (ext2, swap and FAT32). So those commands whould probably mean ext2 filesystem creation. I'm sure Amon-Ra could give us more information on this subject because he added them to the image.
Have you checked your SD card?.
PD: I'm waiting for my N21 . So I can't test yet.
Click to expand...
Click to collapse
Thank you for that insight.
I am not sure what RA's recovery would have done on its own...
but I have initiated and completed successfully a partition of my SDCard that includes FAT32, swap, and ext2.
Now that I have done this, for experimentation really, I don't know how to use it and what it gives me.
Obviously the swap is useless because I would need a cooked Android ROM that would actually utilize swap.
ext2 is probably for apps2sd... which I tried unsuccessfully - probably because of my own mistake.
I will continue trying and report again later.
As far as Amon_RA, he mentioned he was working on upgrading all the recovery images he has put out to the next version - thus we will be in queue until this comes to pass. Maybe we can just skip this version and go to the next

N21 vs DSTL1: stock comparisons
I have completed the comparison of recovery images of the DSTL1 and N21.
For this test I used an original mtd2.img from my DSTL1 and an original mtd2.img from Slemmen's N21.
The recovery images are identical:
Both mt2.img are 4,194,304 bytes
Both mtd2.img-kernel are 2,141,616 bytes
Both mtd2.img-ramdisk.gz are 386,645 bytes
What is also interesting to note is that the two boot images i inspected were also identical.
The DSTL1 boot image is one that came with the 1502 update from General Mobile (which may or may not be identical to the original).
The original N21 boot image, thanks to ikarishinjisan, is identical to the DSTL1 boot image:
Both mt1.img are 4,194,304 bytes
Both mtd1.img-kernel are 2,141,816 bytes
Both mtd1.img-ramdisk.gz are 148,671 bytes
*Notice how both recovery and boot are the same size... must be padded?
*Notice how boot kernel is 200 bytes more than recovery kernel.... interesting...
On a side note:
Bootloader is identical as expected: both ikarishinjisan's and my mtd0.img are 1,048,576 bytes.

If things are going to go custom, it might make some sense to put ext3 filesystems on these things.. ext3 is just ext2 with journalling, which could be helpful since phones can just die/get dropped/lose connection with battery/whatever.

Also, this can be done with the tools already there..
mkfs.ext2
tune2fs -j

dnfm said:
Also, this can be done with the tools already there..
mkfs.ext2
tune2fs -j
Click to expand...
Click to collapse
Are you referring to the Amon_RA's custom recovery?
I can't get tune2fs onto the recovery without trickery, definitely not noob friendly... until we figure out why.
But great suggestion
I'm guessing the ROM must be coded to make use of ext3, otherwise its worthless?

The kernel would need to be configured to support ext3.

Do any Kernels Support Linux Installer?

I've tried most of the kernels on this forum, though I haven't found one that "Linux Installer" plays nice with. Each time I try it greets me with a messages about the kernel not supporting LOOP features, and a lack of EXT2 or EXT3 support . Anybody know of a kernel or anything I can do to enable these?
Thanks!

I'm not sure how well it would work, but for ext2/3 you could compile just the module then, assuming thats all it needs, try using insmod to load it into kernel space

vaderj said:
I'm not sure how well it would work, but for ext2/3 you could compile just the module then, assuming thats all it needs, try using insmod to load it into kernel space
Click to expand...
Click to collapse
Not saying that you didn't know what I was talking about, but just so that everybody is on the same page;
http://www.androlib.com/android.application.com-galoula-linuxinstall-tFjz.aspx
I suppose I could do that to try to enable ext2 or 3, but any idea what LOOP is?

http://forum.xda-developers.com/showthread.php?p=16961006
3.3 is out. Please update, and contact me by email if any trouble. [email protected]
Galoula made a huge update; I did all translations and debug. New tutorial, new quick installation guide.
Loop is a feature of Linux kernel; the symbole name you need to activate when you rebuild kernel is:
CONFIG_BLK_DEV_LOOP=y
As of today, most ROM now support it.

Warning: If you use any Lagfix Based on Universal Lag Fix (ULF/ULFK)

I came across this post:
SpeedMod based (Doc's ROM and others) and every other Universal Lagfix corrupt badly /system
Thus is will cause the user Some FC overtime, Slow downs, The inability to Revert the lagfix.. or complete system failure.
It means that as long as they don't restore a /system with Odin, they're stuck on kernels using broken mount options.
Want proof
https://github.com/sztupy/universal_...e-init.sh#L273
Highlighted line is using wrong and corruption mount points
Second Issue:
Even with Advance NO RFS Config selected... RFS is still used in /system mounts... Dangerous And mean phone are slowly Dying of corruption..
Click to expand...
Click to collapse
Source: http://forums.hardwarezone.com.sg/showthread.php?t=2998903
Does anyone know what he is warning about?

XxDrAg0nxX said:
I came across this post:
Source: http://forums.hardwarezone.com.sg/showthread.php?t=2998903
Does anyone know what he is warning about?
Click to expand...
Click to collapse
Does someone tell you to check in the forum before starting a thread?

That post is from Supercurio in his tweeter page.He is working on his lagfix for froyo and came out with that today.It would be nice if he could come here and explain further more.
ps i see now that is already another thread with this subject and Ryan tried to explain a little whats happening

Copied my response from other thread on this issue to try and avert panic in case it turns out to be false - don't drop your sztupy kernel just yet - sztupy may be doing the correct thing here, he does usually know what he's doing!
Not 100% sure on this, since I have not used or looked at sztupy's lagfix very much, but that line you are pointing out is not a problem.
If /system is EXT4, then calling mount -t rfs on it will simply return an error message, and not mount it. It will do exactly nothing.
The following line would then mount it correctly.
Basically, this seems to be totally false. More evidence please.
Click to expand...
Click to collapse
EDIT: Okay, OP was updated with better information. Lack of check=no means that the FAT32 check *may* be running on the /system, which would cause corruption.
Probably a good idea to confirm if the filesystem check is actually happening though!
And there should probably only be 1 thread on this issue, this one should be closed!

Well. Dont overreact. I've been running sztupy's kernel fork -> raspdeep's oc for a time being, NO PROBLEMS AT ALL.
Dont confuse users.

Changing a file system doesn't corrupt anything, that's BS. Also long time JFS and EXT4 user.

[Kernel] - GB's Steam Kernel - OC/UV or Stock. Made from Unicorns and win.

What is a Steam Kernel?
This kernel uses SztupY's Steam Recovery instead of the standard ClockworkMod. Steam is based off of ClockworkMod, so all of the features you're looking for are here.
If it's based on ClockworkMod, then why would I want to install this?
Steam is a successor to the Universal Lagfix Kernel SztupY also made. Steam has a touchscreen interface at recovery, and a number of lagfix options, just like the ULFK, but with some additional options. Steam has options to convert /system to ext4 or jfs on top of the regular lagfix options. So, instead of using the buttons to locate that new ROM or theme or whatever, you just scroll down your screeen. Steam also has some advanced security features, which you can read about in SztupY's posts. One of the coolest things about Steam is that it automagically detects what filesystems you are using and re-writes init on the fly. So, if you're using an ext4 or jfs lagfix, you don't have to disable it before flashing Steam.
As you may have seen, there are two (I think minor) issues. For one, if you do it the way MikeyMike had people do it (use Voodoo to convert --> ext4), when Steam loads it will may mount /system nosuid, and it will seem like you've lost root. You haven't. It seems that either doing a /system conversion resolves this, so switch from /system formatted as ext4 to /system whatever, OR boot to Steam recovery, under 'boot options' select 'adb always on' and 'adb always root' or something like that, boot the phone, fire up adb and type
Code:
mount -o remount,suid /dev/block/stl9 /system
This will allow /system to be mounted with su access (kinda important!).
The other issue is that when you do a filesystem conversion on /dbdata or /data (one or both, I can't remember) after everything is done, you will get boot loops, doing a hard reset (hold down volume up/down/ and power)resolves this.
If you aren't doing filesystem conversions all the time, then this won't bother you much and these kernels are otherwise stable. This isn't a fault of Steam, SztupY designed it for 2.2, and we're using it on 2.2.1, a couple glitches would be anticipated, and these aren't anything that, imo, affect performance or stability.
As always - when doing these kinds of backups, make sure you have plenty of room on your SD card, or more than the total of the sizes of /data, /dbdata, /cache combined.
Finally, Steam NEEDS to be flashed either by Neldar's SGS Kernel Flashing App, or Heimdall (now for PC and OS X I think) or Odin via a tar file. I can't upload .tar files to xda, so I've attached a couple zips. These CANNOT BE FLASHED VIA CLOCKWORKMOD.
I've uploaded two kernels and a initramfs for anyone who wants to make a Steam kernel of their own. The OC/UV kernel is like my other ones, hopefully no issues with charging, voltage and clock speed can be controlled by xan's app, read other kernel thread for more info. The other kernel is basically a 'stock' reoriented kernel with Steam recovery.
Both kernels also have Neldar's 2.3 BacklightNotification Mod.
Some links about Steam
Here, and here.
Credits
Xcaliburinhand
SztupY
raspdeep
neldar
xan

So, if you think you're phone is getting 'charge death' (I prefer 'charger instability'...sounds a lot nicer doesn't it? ) try a couple things. (I don't think this is an issue with the Steam kernel here or with the most recent one from my other kernel thread, but if it is...)
- Get any kernel w/o the oc/uv patch.
- If you still want to try to find a oc/uv kernel which works for you, don't undervolt at all and tell me if it still happens with kernel #7 (12-23 build from my other thread). As far as I know, no one has had an issue with charger instability on that kernel. If it does still happen, I need to know the kernel version # and for good measure, the production code under your battery (can someone tell me what the name for this is again, I don't feel like shutting off my phone to check), it will be a number like 08.10, 10.10, etc.
- For it to be charge death, it has to occur while charging (I know, but you'd be surprised), it has to happen with a oc/uv kernel, you CANNOT have any setCPU 'screen off' profiles' (it's not just this kernel, screen off doesn't play nice on our phones afaik), and you cannot have any undervolt values set. (Read that closely - I'm not saying you can't UV, just that if it seems like charge death, remove all UV when charging and see if it happens. More below.)
- The reason I ask you to not undervolt at all and see if it happens is because I don't know if every other oc/uv kernel uses the stock factory voltages, so you may have been using UV settings that are referenced from an over-volted kernel, and so you might confuse freeze with charger instability.
- If even with the 12/23 build f kernels and not undervolting at all, you're still get shutdowns when charging, you probably want to get a different kernel. If you insist upon using that one anyway, try charging via USB instead of the wall outlet, it seemed to happen less frequently on older kernels, and I haven't had a charge death in weeks now, so, I'm good at least.
- See if your phone is one of the ones being recalled. If your phone is under recall and these don't work for you, I'm not sure what else I can do.
- These fixes work for me and a lot other people who had the same problem with other oc/uv kernels. Like I said, we're running these out of spec, so a few unlucky souls might not have phones that can handle this. Or maybe some of these kernels have been sprinkled with pixie dust and others haven't. If you find a different kernel that works for you by all means use it. It's all about choice people.

Thanks for posting this and for all your help in the other threads.
Sent from my liberated Captivate via XDA App.

Ok I am using the steam recovery in serendipity and you say doing it that way makes you seem like you have lost root. I haven't had any issues with my apps on my phone that require root but steam gives me a status 2 error when trying to flash themes...would doing a system conversion fix that or is that a totally different problem?
Sent from my SAMSUNG-SGH-I897 using XDA App

Anything different from the attached kernel in this thread and the one in Mikey's rom?

That could be it because you're probably trying to write to system with the update.zip. Check by running an adb shell (or fire up the terminal emulator app) and just type 'mount'. If you see something like
Code:
/dev/block/stl9 on /system type rfs (rw,[B]nosuid[/B],nodev,relatime,vfat,llw,check=no,gid/uid/rwx,iocharset=utf8)
then yeah. Or like I said, use adb, but you might have to do that after every boot. Fileysystem conversion seems to be good.
Steam re-writes init on the fly, so if it's not doing the conversions at first, it apparently defaults to nosuid.

bts0uth said:
Anything different from the attached kernel in this thread and the one in Mikey's rom?
Click to expand...
Click to collapse
Ah well just updated to BLN 2.3, and added the no oc/uv one for people who don't want that.

This is what mine says when typing mount in terminal emulator...right or wrong?
/dev/block/stl9 on /system type ext4 (rw,noatime,barrier=0,data=writeback,noauto_da_alloc)

Could we flash the no oc/uv over the stock kernel in serendipity without disabling voodoo?
Sent from my SAMSUNG-SGH-I897 using XDA App

Gurgs said:
This is what mine says when typing mount in terminal emulator...right or wrong?
/dev/block/stl9 on /system type ext4 (rw,noatime,barrier=0,data=writeback,noauto_da_alloc)
Click to expand...
Click to collapse
If you don't see nosuid, don't worry about it. I had had Steam recovery on my phone all last week but I went from RFS --> jfs as soon as I flashed so I had no idea this was an issue before it was released. MikeyMike had the idea of putting on the ROM and people could try it out, which I thought was pretty good, and still is. Just wasn't quite as easy as we thought.

crupp said:
Could we flash the no oc/uv over the stock kernel in serendipity without disabling voodoo?
Sent from my SAMSUNG-SGH-I897 using XDA App
Click to expand...
Click to collapse
Yes. BUT, since you aren't doing a /system conversion, what I wrote in the OP will probably apply to you.

Any progress on Voltage Control sticking?

MikeyMike01 said:
Any progress on Voltage Control sticking?
Click to expand...
Click to collapse
Any progress on making a ROM that doesn't have nine version in 48 hours?

glitterballs said:
Any progress on making a ROM that doesn't have nine version in 48 hours?
Click to expand...
Click to collapse
At least I fix what's wrong.

What is steam? This isnt a kernel we can simply flash with Odin?

MikeyMike01 said:
At least I fix what's wrong.
Click to expand...
Click to collapse
I'm flashing 1.9 now so we'll see about that.

psufan5 said:
What is steam? This isnt a kernel we can simply flash with Odin?
Click to expand...
Click to collapse
Steam is similar to cwm. It uses a pretty cool touch screen interface. Try sgs kernel flasher, its really easy to use. Don't forget to make a backup first.
Sent from my liberated Captivate via XDA App.

glitterballs said:
Any progress on making a ROM that doesn't have nine version in 48 hours?
Click to expand...
Click to collapse
You can, you just have to make a .tar of the zImage. You can't u/l .tar to XDA for whatever reason, so just posted zips.

MikeyMike01 said:
Any progress on Voltage Control sticking?
Click to expand...
Click to collapse
My voltages have been sticking since I downloaded your rom...i must of just got lucky or something...

Gurgs said:
My voltages have been sticking since I downloaded your rom...i must of just got lucky or something...
Click to expand...
Click to collapse
It sticks with the normal kernel, but not the steam one.

LolBoot xD SGS2 dualboot - NEW 12.12.11: Easy-Setup App v2.51

(I wasn't really sure if this might fit into "Development", so I put it here, maybe a mod will move it, if it's a dev topic )
Anyways, here we go, I DUALBOOTED two different, independant ROMs on the S2
Video of dualboot in action: http://www.youtube.com/watch?v=l9-V_6Ua_D0
** THIS IS NOT (YET) COMPATIBLE **
** WITH ICS (ANDROID 4.0.x) ROMS! **
-- this goes for custom ROMs as well as stock ROMs --
Icey Sammich compatibility will be added once Sammy released their ICS kernel sources.​
!!! There now is an app for more convinient and easy setup of the dualboot !!!
(04.11.2011) DualBoot setup app v2.00: http://forum.xda-developers.com/showpost.php?p=19049047&postcount=94
(12.12.2011) App has been updated to 2.51, lot's of good new stuff! >> Free Version -- Donate Version <<
Click to expand...
Click to collapse
First off:
This is only a little experiment I did like "c'mon, has to be possible" - this is NOT (at least yet) tweaked for usability and anything the like, just a humble experiment.
That said, don't flame me if things are rather complexicated to do this ATM.
Maybe I'll come up with a more userfriendly way of setting this up, maybe someone else does, maybe no one does.
Also now that I found a base on what to do, there might be different ways (more easy ones maybe) to set this up, I'll keep toying around with it.
But let's cut to the chase, shall we
So, how was this set up? I'll give a brief rundown of what I did:
I edited a few .rc files in the initramfs of the kernel to make it actually perform a full boot when recovery mode was triggered and to fire up recovery mode when in battery-charging mode.
I also edited a few mounts in the boot .rc for the 2nd OS (in "recovery" mode) to use different partitions for /system and /data, so that we'd end up with really independant installs.
What partitions did I missuse for that:
partition 12 (mostly unused, only when installing a stock ROM AFAIK) for /system - that's a neat choice IMO as p12 is 512MB in size, just as p9 where /system usually sits on
partition 7 (which is usually /cache) for /data
gives us only 100MB of user data space, but for now that's OK, as said, it's only an experiment on how such a thing could be done.
with the original partition for /cache "gone", I mounted a tmpfs for it.
So the OS still has a usable /cache
Then I set up the two OSes:
(dualboot kernel not yet flashed)
Launchprep part 1:
I made a CWM backup of my normal installation I was running (stock XXKG6 at the time).
I installed DevNull-Test AOSP as to it's instructions
Some su'ed voodoo via a terminal while having the 2nd OS (the DevNull AOSP one, in this case) installed - best done in recovery mode via ADB:
rm -Rf /cache/*
cp -Rp /data/* /cache/
dd if=/dev/block/mmcblk0p9 of=/dev/block/mmcblk0p12 bs=4096
That did "set up" the 2nd OS to where it's supposed to go.
Launchprep part 2:
Then, "advanced restore" of the backup made a few minutes earlier:
- boot
- system
- data
Reboot
At this point OS #1 is running again and OS #2 is sitting in hiding, prepared to roll - so, let's roll:
Flashed the modified "dualboot kernel" (via an App or Odin or magic, doesn't matter).
---> DONE <---
reached the point to where everything works as shown in the video.
As said above already, yes it needs some manual work to set it up, yes there's a lot of things that might not work, yes there are other/better ways to set it up.
It's only a humble experiment - lot's of space for improvement.
Maybe you like it - for those who do, I wanted to share this
Attached to this post you find the modified kernel I used, it's based on my v1.20 custom kernel (see sig) but with the above mentioned changes.

I've seen the video m8, this is totally different approach, ur giving this device a new dimension. love u "in a straight way" hahaa

there currently an app called Bootmanager which also handle up to quadruple booting. But sadly currently only support HTC phones.
http://www.appbrain.com/app/bootmanager/com.drx2.bootmanager
well, one can hope!

Thanks OP this is an awesome concept! Very happy to see you posted it with a video! and nice boot animation!

sunwee said:
there currently an app called Bootmanager which also handle up to quadruple booting. But sadly currently only support HTC phones.
Click to expand...
Click to collapse
Yeah, that's the thing.... that app is HTC only.... but we have Samsung S-II and want dualboot as well.
I'm already brainstorming on how to enhance the actual usability of this, i.e. flashing a 2nd OS directely to it's place instead of first installing it to the main system partition. But there is problems when /data is not mounted to the original partition, at least stock doesn't like it on initial boot.... well, well....

That is great. Going to use this for sure. This should be in development for sure.
Congratulations already.
Sent from my GT-I9100 using Tapatalk

This is impressive bro sure will use it
but i want to ask one thing
SD card needed for this or not ?

That would be really cool (and definitely should goes to original development). Does it work with CM7/MIUI + custom rom?

vikas776 said:
SD card needed for this or not ?
Click to expand...
Click to collapse
No, so far this completely works with all internal storage.
But I have a few ideas I have yet to try to get mounted from other places - like images in /sdcard for example (I *so* hope that'll work.... )

Hi
Does this kernel include any of the Hellcat kernel tweaks or are they work in progress.
Sent from my GT-I9100 using Tapatalk

Tricky103 said:
Does this kernel include any of the Hellcat kernel tweaks or are they work in progress.
Click to expand...
Click to collapse
I made this build based on my v1.20 custom kernel, so it has everthing that one has - plus the touchfix already

exactly what i was hoping for.
great job - pls continue your work

Hi i tried this with instanity rom last night. When I use the three buttons to boot it just sits there not booting. My guess is the kernel is not compatible. Unless I made a mistake somewhere.
Sent from my GT-I9100 using Tapatalk

Hm, yah, might be that the kernel isn't fully compatible with that ROM, what kernel does the ROM usually use?
Did you boot it up fully at least once before copying /data to /cache ?

Yes I did fully boot up. But his kernel didn't have advanced activated in recovery so I flashed your kernel and moved the cache okay. But it said /data not found when I ran the 2nd command line.
I will flash aosp later. I like that rom.
I am not sure what kernel nitr8 uses. I think it is his own, Insane.tar would you like it to see if they can work together.
Sent from my GT-I9100 using Tapatalk

Tricky103 said:
But it said /data not found when I ran the 2nd command line.
Click to expand...
Click to collapse
Hm, yeah, that sounds like something didn't work.... make sure you run those commands as root, i.e. "su" as very first command (I'll add that to the first post).
Give me a direct link to the ROM and I'll try it.
Make take a few days though as I'm away from my computer a lot because of work the next two days, but I'll try once time permits.
Well yeah, and this still is in highly experimental stage, if I (or someone else) should ever get this to more stable and reliable state, I'll make an easy to use installer/setup tool
But I got a few other ideas on setting it up I have to try first....

http://goo.gl/2uZCh
This is the complete rom. Only 47mb. I thought you would like the whole rom

Tricky103 said:
Hi
Does this kernel include any of the Hellcat kernel tweaks or are they work in progress.
Sent from my GT-I9100 using Tapatalk
Click to expand...
Click to collapse
May be someday WINDOWS Mo 7 and Android on our sweet beast

Hi
I tried again with Aosp Dev-null. I still get this error "cp: can't stat '/data/*': No such file or directory "
after running this command line " cp -Rp /data/* /cache/ "
Any Ideas ?
It still doesn't boot if I press 3 button it brings up the boot logo and then black screens until it boots to the 1st partition.

Thanks for the link, will download and try as soon as time permits.
Also, try this command sequence, I got an idea what the issue maybe might be, give it a shot:
Code:
su
rm -Rf /cache/*
busybox cp -Rp /data/* /cache/
dd if=/dev/block/mmcblk0p9 of=/dev/block/mmcblk0p12 bs=4096
(use "busybox cp" instead of plain "cp", maybe it helps)
And some update on my ongoing thoughts for those interested:
- got an idea on how to make a more easy to use App for prepping and setting up the dualboot environment
- managed to do a neat thing I didn't really think it would work: issued a "mount" command and the OS thought it was mounting a partition of the internal flash (/dev/block/mmcblk0p12 in this test, but was testing for later on actually doing it with p9 - you might see where I'm headed here ) but instead of the partition it actually mounted from an .img file! (loopback)
i.e. "mount /dev/block/mmcblk0p12 /somedir" actually mounted "/somepath/someimage.img" to "/somedir" instead of the partition from /dev/block/... (you just gotta love Linux and it's flexible way of handling things....)
NOW, imagine /dev/block/mmcblk0p9 (the partition carrying the system) and p10 (data) being (kinda) transparently mounted from an IMAGE FILE
I "only" have to find a way to sneak this in before init starts mounting stuff.
If there's a way to do THAT.... unlimited multiboot from OS images, anyone?
(so far this is kinda dreaming, but would be cool to get it working )