Cracking this ROM for the P700

[Finless]

OK I got the system, files. I will work on a ROM today.

Bob

[x51]

Are these 100% the same for the P700? Remember in /system are the /lib and drivers within. If they do not match this hardware, it will not work! We need to make sure when making this ROM system.img is made specifically for the P700 Bob

My Tab is the 7200 I was under the impression only the amount of Storage was different.. anyone know? Edit: Looks different based on what I see here: http://southerntelecom.com/polaroidsupport/firmware/

[Finless]

I just got it to compile, by chance did you delete the first line? I tried to compile with all three lines and it failed, removed the line:

//u32 namelen:CRAMFS_NAMELEN_WIDTH, offset:CRAMFS_OFFSET_WIDTH;

then save and follow the rest of those steps. It compiled just fine for me and it was able to dump the image extremely quick.

files uploading now

extracted system image: http://db.tt/VTMfESAu

Is this for the P700 or P7200?

Bob

[chidave09]

Those files are from the pmid700. I don't have the 7200, but I can get the files when I get home.

@Finless Could you possibly clue me in on what mods you made to the boot.img and how you plan to repack the system.img and boot.img? I would really appreciate it as I would like to make my own mods.

[Finless]

OK folks, here is my firt TEST ROM.

Read the post here for the details.

http://www.freaktab.com/showthread.php?103-Polaroid-P700-TEST-ROM-1-0-by-Finless

Let me know how it works.

Chidave, hang tight man. Let me make sure stuff works first. Hate to have you chasing ghosts if I cant do it right first. Then I will tell you what you have to do. This one was a little different to take apart.

Bob

[chidave09]

This one was a little different to take apart.

Bob[/QUOTE]

That is for sure! I already went ahead and did the following:

$ mkcramfs system system.temp.img
$ rkcrc system.temp.img system.signed.img

and I got an endless bootloop. So, I did the following

$ mkcramfs system system.temp.img
$ rkcrc -p system.temp.img system.signed.img

the result was it is stuck on the very last step of the boot. I did NOT modify anything before remaking it, which leads me to believe, either mkcramfs or rkcrc needs to modded. I have a good feeling it is rkcrc since I got different results from adding the argument -p.

I also played with the steps from the guide to extracting this particular boot.img from the guide on xda and I discovered a little something. When I tried this step it failed saying it wasn't a proper archive:

$ mv boot.img boot.img.7z
$ 7z l boot.img.7z

so instead, I restarted, skipping this step. When I got to boot.img I just gave it a right click and "extract here". Worked just fine without the 7zip step

[Finless]

You do not use rkcrc on system.img. That used for boot.img only.

Do this:

If using Ubuntu or something that you are not root logged on please use the sudo command to run this script. Make sure the system.img is not already mounted!!! If so
sudo umount system

Copy these lines into a new document. Call it run.sh

Then at the command prompt type sudo bash run.sh
It should compete without errors. Ignore the block specific device warnng and answer y to the prompt when it comes up.

Here is the script:

#!/bin/sh

mkdir system
mkdir system2
sudo mount -t cramfs -o loop system.img system
sudo dd if=/dev/zero of=system2.img bs=1M count=180
sudo /sbin/mkfs.ext3 system2.img
sudo mount -t ext3 -o loop system2.img system2
sudo cp -r system/* system2
sudo umount system
sudo umount system2


OK once done post a copy of the system2.img and I will try again to make the ROM.

Bob

[Finless]

OK I have some other ideas I am going to work on tomorrow but I could use the system2.img as explained above.

Again you do not rkcrc a ext3 or cramfs system.img on RK29.
Boot.img you do use rkcrc on as it is a modified gzip file.

Bob

[Finless]

OK I am going to have to get this modded cramfs binary compiled. I ran into yet another ROM with this setup of system.img. Why the HECK therse manfuacturers are doing this non-standard cramfs is beyond me! Well maybe on purpose to stop rooting

Anway any progress on your end chidave?

Bob

[chidave09]

I have to wait til I get home to try, but I didn't cp anything, I just extracted the image and posted it. Also, I tried the system repack without rkcrc and that just boot looped. Also, your images didn't boot at all. Just said download ok and went straight back to recovery mode. Didn't even come on to format partitions. I think this may be due to large of a system position or something like that. One of my modded CM7 images did the same thing when it was really big

[Finless]

The size really should not matter for how large system is. On all the other tablets I did, it was no problem and these are all RK29 architecture. I can try the minimum size for ext3 with no extra room if you like.

However I am thinking that they changed some of the binaries for support of ext3, etc. I mean it is clear they modified the cramfs binary! If they did the same to the ext3 binary then this could be whats up. Since the binary for ext3 will be the same for all RK29 tablets, my thought was to replace both the ext3 and cramfs binaries from a tablet that is know to work with standard formats of these.

So here is the plan. Let me know what you think. As you can see with the RKAndroid tool you can flash one of the imgs instead of all of them. So what we try to do is replace the cramfs binary in /system from my known standard cramfs binary I have for my Arnova. Then as a first test we convert the modified cramfs to a standard cramfs, flash only system.img and see if it boots. Once we have that working we will no longer be on this problematic custom cramfs. Now we should be able to make progress. e.g. little baby steps. Modding too much at one time trust me can drive you nuts! It did for me the first time I cracked one of these as I could not figure out exactly what the problem was until I started flashing one img at a time.

What you think?

Bob

[Finless]

Dave, let me know when you can test. I want to try something REALLY simple. Take apart boot.img, add only a few permission changes so Root Explorer can write to /data and /root. No EXT3 conversion!, and have you flash ONLY boot.img using the flash tool. If it boots we know one step is out of the way.

You willing?

Bob

[Finless]

OK COOL!

Not sure where everyone went that was interested in this root but I decided to flash my Arnova 10 G2 with this Polaroid P700 stock ROM. Guess what! It boots to the welcome screen!
Of course due to drivers the touch screen does not work but at least know I can do a ADB pull of the /system without the crappy cramfs getting in the way! I can also test my mods to see if it boots!

So stay tuned....

Bob

[chidave09]

Awesome news! On my way home now and I am ready and willing to test anything!

[chidave09]

tested your script, still can't mount system, here is my output