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What are the different partitions used for?

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I finally managed to work out how to edit partition_zte.mbn to change the partition sizes yesterday, and managed to edit it to make a working layout from one of wbaws layouts. Most of the partitions are self explanatory, but what are the persist, misc and oem partitions used for? I assume oem isn't that important as it seems to have been made as small as possible. The other two seem to be the same size in every layout, so I assume they must be needed for something, but does anyone know what that is?

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I finally managed to work out how to edit partition_zte.mbn to change the partition sizes yesterday, and managed to edit it to make a working layout from one of wbaws layouts. Most of the partitions are self explanatory, but what are the persist, misc and oem partitions used for? I assume oem isn't that important as it seems to have been made as small as possible. The other two seem to be the same size in every layout, so I assume they must be needed for something, but does anyone know what that is?

OEM = Original Equipment Manufacturer

That is specifically dependent on what code/data is put in there for the purpose to have a functioning handset, perhaps, a burned in ROM image of a radio chipset...no one knows really until you disassemble it.

Can obviously guess persist is to hold data that persists after the handset is powered off. As for misc no idea.... :D

Why are you re-editing the layouts when wbaw's TPT procedure does exactly that? :) (Just curious as a lot of gen2 users who did TPT flashing are quite happy with the partition layouts... just saying.. :) )

Edited by t0mm13b

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Why are you re-editing the layouts when wbaw's TPT procedure does exactly that? :) (Just curious as a lot of gen2 users who did TPT flashing are quite happy with the partition layouts... just saying.. :) )

Well it's always fun to have a play..... I'm sure he's just curious

That's what android is all about :)

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Well it's always fun to have a play..... I'm sure he's just curious

That's what android is all about :)

yeah, couldnt agree more but at the same time, there's a risk involved - what happens if you go "past the point of no return"... :) That's even more fun! :D

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yeah, couldnt agree more but at the same time, there's a risk involved - what happens if you go "past the point of no return"... :) That's even more fun! :D

yer, fair point actually. to anyone reading this, partition changing is a lot more dangerous than the standard ROM changing via clockwork.

Pretty much anything can be un-bricked if done by clockwork. When using tpt's or similar it can, potentially, fully brick your phone.

Saying that tho, it never stopped me toying about with my blade so I guess its not guna stop many people. I guess that's a major plus point about the blade. I wouldn' have tried sum of the stuff I have if I had a £400 phone.

Happy un-bricking people :)

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OEM = Original Equipment Manufacturer

That is specifically dependent on what code/data is put in there for the purpose to have a functioning handset, perhaps, a burned in ROM image of a radio chipset...no one knows really until you disassemble it.

Can obviously guess persist is to hold data that persists after the handset is powered off. As for misc no idea.... :D

Thanks, I thought it might be something like that, but just wanted to see.

Why are you re-editing the layouts when wbaw's TPT procedure does exactly that? :) (Just curious as a lot of gen2 users who did TPT flashing are quite happy with the partition layouts... just saying.. :) )

I was curious as to how they were created, so wanted to see that. wbaw's layouts also come in fixed sizes whereas if I know how to change them I could make one thats exactly right for what I want/need. Also, I wanted to see how practical it would be to offer the ability to pick your own partition sizes (within reason) in my app. I understand that there is a risk involved, but I checked what I was doing made some sense before I ran the TPT and had one of wbaw's ready in case something went wrong. I wasn't changing any of the firmware partitions, so I guessed I couldn't do anything too bad. (I did have a worried moment when I copied two appsboot.mbn's by mistake instead of one and an appsboothd.mbn, but pulling the battery and trying again with the right files worked ok.)

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yer, fair point actually. to anyone reading this, partition changing is a lot more dangerous than the standard ROM changing via clockwork.

Pretty much anything can be un-bricked if done by clockwork. When using tpt's or similar it can, potentially, fully brick your phone.

Saying that tho, it never stopped me toying about with my blade so I guess its not guna stop many people. I guess that's a major plus point about the blade. I wouldn' have tried sum of the stuff I have if I had a £400 phone.

Happy un-bricking people :)

Heh, posted at the same time.

It's a good point, and like you if I had a really expensive phone I probably wouldn't try it. The Blade seems quite good for having lots of options to unbrick it, using a working TPT seem to work as long as you haven't broken the bit that starts the TPT. From reading the debricking thread, it seems as though if none of the ways we have to unbrick it work, nothing can save it. I suppose if everything went really bad, you still have the option to return it to Orange and they couldn't tell what had happened to it.

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Sorry, I don't know enough about it to help at all. As far as I know, some of the Chinese versions work differently.

Yep, in this case I can provide any needed information, /proc/iomem, /proc/mtd ... anything.

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The oem partition is used by gen2 stock roms to automatically mount a windows driver cd iso (/system/etc/pcsuite.iso) over usb when connected to a windows pc. It seems to copy the iso to the oem partition & then that is read over usb. It isn't used by any custom roms. No idea why it's a 15mb partition when the driver iso is under 5mb.

No idea what persist & misc are used for, or if they're used at all on the blade, but they're only tiny, so it's not worth the chance of breaking something, imo.

As for TPTs breaking your phone, oemsbl.mbn & qcsbl.mbn are the only really dangerous files to mess with, mess those up & your phone is a real brick, needs jtag to fix. If you alter partition.mbn then it wont flash. You can do what you like with rest, at worst you should need a working tpt to fix it. There also seems to be some very small chance of freak problems, TomG said he flashed a known working tpt to a phone once & it just decided to wipe all the first part of his phone's nand & brick it, I've no idea how that could have happened, but i don't doubt that it did.

Another little note, the raw nand (not yaffs) partitions - boot, recovery, splash & oem should be a few blocks bigger than the data they're storing, they need spare blocks in case anybody has a bad block in the wrong part of the nand. Also, if you move the splash partition, then you also need to hack another bit of appsboot.mbn - cpg did that for me, he disassembled it, it's not as simple as hacking the partition table.

TPTs to change the partition sizes of chinese v880 phones could be made, but they'll need to hack chinese firmware. A European appsboot.mbn will cause a chinese phone to not boot, because the european phones have 512mb ram & the v880s only have 256mb. The v880 has different nvitems to the european blade so the european amss.mbn wont work on them by tpt either.

If anybody with a v880 wants to do it, all they need to do is extract a chinese image.bin using cpg's ztepack, remove all the .img files, copy clockworkmod as boot.img & recovery.img, add a blank yaffs userdata.img & system.img, open partition_zte.mbn & appsboot.mbn with a hex editor, hack the partition tables in them & repack it into an image.bin with ztepack.

If you're going to do image.bin gen2 tpts for your tpt helper app then you'll need to be able to detect chinese phones, so that people don't break their v880s (they're recoverable by flashing a proper v880 tpt) by flashing european firmware. differences in /proc/iomem should be able to help you do that. Other zte devices will tpt too & will break if blade tpts are flashed to them.

Edited by wbaw
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wbaw, thats seems to be not so easy for me.... Damn chinese phone....

If anyone could help me.. sad.gif

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lots of useful stuff

Thanks for the info. I'd read about leaving extra space, so I was just going to leave boot/recovery/etc alone as they don't have much to work with already. I was planning to leave oemsbl.mbn alone as I've no idea what they do. I'm not going to add the gen2 tpts just yet. As you say, they could brick Chinese phones, so I'll wait until I'm sure I can avoid that.

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Its possible to use chinese cefs.mbn and amss.mbn on a european blade but you need to use the v880 tool (recommended - can do it in less steps) or the windows flasher.

Someone should try the reverse. (As long as you make sure you use chinese qcpbl and oemsbl you will be able to recover in all circumstances.)

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