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FW Developer
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I wanted to pose a few questions here that I havent really seen discussed.

Is there any known reason that we couldnt use nvflash to set up custom partitions on the NAND memory that would mimic the partition structure that a normal desktop linux system would set up?

Is the current partition structure found on our gtabs a limit of the hardware, or of android in particular?

If there are no real constraints to what the hardware can handle, would anyone actually want to try toying with the partition structure to see if a working full linux system could be installed?

I have been playing with nvflash commands in linux and have been creating some scripts that I may be able to work with for full partition backup and restore, along with some config files that may allow different (more conventional) linux mount points to be used. I will update this post as I come up with anything interesting.
 

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The internal nand accessed by and configured with nvflash is comparably small. The 16G sdcard portion is entirely different.

Yes you can use nvflash to repartition the nand. A small distro ( less than 600M or so) would fit.
 

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TeamDRH
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Ok, this has been eating at me for a while now. I have searched the web for answers, but maybe someone else has already found the definitive answer.

All info I have found regarding the gTab has stated that the 16gb internal memory IS the NAND. I have seen kernel argument lines posted that possibly shows the kernel is allocating the file space amount on the internal memory rather than some kind of separate NAND chip being 512mb in size. Can someone out there debunk my theory?

In the past, the NAND on phones and earlier tablets was truly mandated by the size of the internal memory module, which was very small, and relied on a separate SDCard card for most of the storage and personal settings data. The kernels had that minimal internal memory configuration baked in and allocated accordingly.

Is it possible that we are overlooking a very key change to compiling the gTab kernels? Something that will allow us to run larger OS systems?

If I am chasing my tail, someone please correct me.
 

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Ok, this has been eating at me for a while now. I have searched the web for answers, but maybe someone else has already found the definitive answer.

All info I have found regarding the gTab has stated that the 16gb internal memory IS the NAND. I have seen kernel argument lines posted that possibly shows the kernel is allocating the file space amount on the internal memory rather than some kind of separate NAND chip being 512mb in size. Can someone out there debunk my theory?

In the past, the NAND on phones and earlier tablets was truly mandated by the size of the internal memory module, which was very small, and relied on a separate SDCard card for most of the storage and personal settings data. The kernels had that minimal internal memory configuration baked in and allocated accordingly.

Is it possible that we are overlooking a very key change to compiling the gTab kernels? Something that will allow us to run larger OS systems?

If I am chasing my tail, someone please correct me.
gTab has 512M ram, a 512M nand & a 16GB internal sd. Most of the partitions are stored on the nand except for /data & /sdcard which are on the internal sd card. When you repartition in CWM you are creating the /data partition (it's the 2048M you enter in CWM) and the remainder becomes /sdcard. Nvflash can only touch the 512M nand which contains the following partitions: BCT (boot configuration table), PT (partition table), EBT (bootloader), MBT (?), BLO (Viewsnic boot logo - 3 birds), MSC (miscellaneous hardware settings), OGO (logo data), SOS (recovery), LNX (kernel), APP (system/rom)& CAC (cache) partitions.
 

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TeamDRH
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gTab has 512M ram, a 512M nand & a 16GB internal sd. Most of the partitions are stored on the nand except for /data & /sdcard which are on the internal sd card. When you repartition in CWM you are creating the /data partition (it's the 2048M you enter in CWM) and the remainder becomes /sdcard. Nvflash can only touch the 512M nand which contains the following partitions: BCT (boot configuration table), PT (partition table), EBT (bootloader), MBT (?), BLO (Viewsnic boot logo - 3 birds), MSC (miscellaneous hardware settings), OGO (logo data), SOS (recovery), LNX (kernel), APP (system/rom)& CAC (cache) partitions.
See, this is my argument. Where is the proof that there is a separate 512mb NAND in the gTab? If there is, then where is that documented?

Al, I'm not discounting the possibility, or fact, but is there proof out there that there is a separate 512mb chip aside from the 16gb internal memory? I have seen many descriptions stating 16gb NAND on the gTab.
 

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See, this is my argument. Where is the proof that there is a separate 512mb NAND in the gTab? If there is, then where is that documented?

Al, I'm not discounting the possibility, or fact, but is there proof out there that there is a separate 512mb chip aside from the 16gb internal memory? I have seen many descriptions stating 16gb NAND on the gTab.
Want proof, try & create a 16GB partition with nvflash & see what it does. Don't have to copy anything to it. Just modify the gtablet.config in nvflash to only create one partition of 16G..you don't even have to copy an image to it...like in the cache partition.

If you think the nand doesn't exist & all resides on the internal sd then how do you account for why nvflash doesn't touch /data & /sdcard & that those are created/formated only via cwm. Want more proof, PM rajeevvp on XDA..he's the resident expert on the nand & can provide further proof. You can also find many posts on the gtab forums where he specifically identifes the nand.
 

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See, this is my argument. Where is the proof that there is a separate 512mb NAND in the gTab? If there is, then where is that documented?

Al, I'm not discounting the possibility, or fact, but is there proof out there that there is a separate 512mb chip aside from the 16gb internal memory? I have seen many descriptions stating 16gb NAND on the gTab.
Here's your proof. The small photo is from the back of the gTab system board (16GB emmc chip & 512M nand). I've provied the info but if you don't believe me, look it up yourself.
 

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Here's your proof. The small photo is from the back of the gTab system board (16GB emmc chip & 512M nand). I've provied the info but if you don't believe me, look it up yourself.
Wow, you're good Al. Believe me, I have searched all over. Thanks for providing this.

Something still bothers me though about this whole setup on the gTab as far as usable data space.
 

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Wow, you're good Al. Believe me, I have searched all over. Thanks for providing this.

Something still bothers me though about this whole setup on the gTab as far as usable data space.
Don't know why it bothers you. It's similar to the set up on other tablets.

My Velocity Cruz (256M ram, 256M nand, 4G internal micro sd, & an external sd slot) uses a similar set up except even apps must fit on the nand.

Good thing we get to use a portion (2G) of our internal sd (eMMC-embedded multimedia card) to install our apps on.
 

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Don't know why it bothers you. It's similar to the set up on other tablets.

My Velocity Cruz (256M ram, 256M nand, 4G internal micro sd, & an external sd slot) uses a similar set up except even apps must fit on the nand.

Good thing we get to use a portion (2G) of our internal sd (eMMC-embedded multimedia card) to install our apps on.
I guess this is exactly what bothers me about tablet manufacturers, still appear to be stuck in cell phone mentality.

Perfect example is that 2gb 'limitation' when there so much more available. I'm not a coder or developer, so I will just continue to wonder I guess. Maybe it's due to fact that I have been a PC guy most of the time.
 

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tlb1961, quick question... can a "known good" working rom be pulled out of the tablet with NVflash and reused as your baseline to flash back to? For instance, I would like to use Brilliant Corners as my baseline instead of 4349, or even a stable 5274 (rooted with market) as a baseline rather than 4349. I am using a Linux setup to do all the processes/work.

My idea is that I would like to use a "known working" baseline for all the ROM breeds available, (Honeycomb, Gingerbread, and Froyo). This way, when I want to change it over, or test, I can just fire up the NVflash and voila, new ROM, apps up and ready, etc.

Any input would be great and thanks in advance.
-Mike
 

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tlb1961, quick question... can a "known good" working rom be pulled out of the tablet with NVflash and reused as your baseline to flash back to? For instance, I would like to use Brilliant Corners as my baseline instead of 4349, or even a stable 5274 (rooted with market) as a baseline rather than 4349. I am using a Linux setup to do all the processes/work.

My idea is that I would like to use a "known working" baseline for all the ROM breeds available, (Honeycomb, Gingerbread, and Froyo). This way, when I want to change it over, or test, I can just fire up the NVflash and voila, new ROM, apps up and ready, etc.

Any input would be great and thanks in advance.
-Mike
Mike,

Yes it is possible to use NVFlash to extract and restore an existing ROM. The backup part can be problematic depending on your NAND condition, and the restore can also be tricky to put together so gTab fully boots.

See this post for basic information (sorry, it was created for Windows): http://forum.xda-developers.com/showthread.php?t=1010659

I have created shell script for Linux which works for the extraction if everything goes well, but I haven't investigated the restore avenue yet as I personally use CWM for ROM backups. I have limited time right now, but I will try to find some time tonight to put together a few things if you need help. In the meantime, read that thread and see what you think.
 

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Mike,

Yes it is possible to use NVFlash to extract and restore an existing ROM. The backup part can be problematic depending on your NAND condition, and the restore can also be tricky to put together so gTab fully boots.

See this post for basic information (sorry, it was created for Windows): http://forum.xda-developers.com/showthread.php?t=1010659

I have created shell script for Linux which works for the extraction if everything goes well, but I haven't investigated the restore avenue yet as I personally use CWM for ROM backups. I have limited time right now, but I will try to find some time tonight to put together a few things if you need help. In the meantime, read that thread and see what you think.
I knew you would be the one to ask. I did one already in cwm. I wasthinking that this may actually be a bit quicker. I read the thread on XDA. I figured you may shed some more light on it than I could get from what I read. Thanks. I've also been having trouble using some commands in nvflash to flash clockwork and a new boot logo. It keeps telling me permission denied. I know I'm typing something incorrectly, but I'm not sure what.

sent from my AOSP CM7 Gtablet with Clemsyn Kernal using Tapatalk
 

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I knew you would be the one to ask. I did one already in cwm. I wasthinking that this may actually be a bit quicker. I read the thread on XDA. I figured you may shed some more light on it than I could get from what I read. Thanks. I've also been having trouble using some commands in nvflash to flash clockwork and a new boot logo. It keeps telling me permission denied. I know I'm typing something incorrectly, but I'm not sure what.

sent from my AOSP CM7 Gtablet with Clemsyn Kernal using Tapatalk
Don't mean to rain on the parade but IMO, nand backup/restore in CWM is much more comprehensive than nvflash backup. Nand bckup takes a snapshot in time, saving not only the nand partitions, but also the /data partition & the .android_secure mount point that reside on the internal sd. Restoring from a nand backup will restore the entire os, system & user settings & all installed apps.

Nvflash only backups the nand partitions. If you do use nvflash to do a backup & later do a restore of it, you must be sure to to a factory/data reset, wipe cache & wipe dalvik after the restore (so that you don't use possibly corrupt data/apps/settings left over from the previous installation).

For those situations that you can not enter CWM, I believe it is faster (and more reliable) to nvflash to the factory image, install CWM & then restore the nand backup (that includes all your apps & settings).

If you read post#42 on the thread Mike identified, you will note that rajeevvp does not recommend using nvflash to backup & restore for the reasons I noted. If you take another look through the thread you will see user "aabbondanza", that's is me.

Nvbackup does have it's uses though. I think it's a great tool to make a copy of your original image so that you always have a copy & especially for your original boot config table (bct - partition 2) & partition table (PT - partition 3).

Al
 

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TeamDRH
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Don't mean to rain on the parade but IMO, nand backup/restore in CWM is much more comprehensive than nvflash backup. Nand bckup takes a snapshot in time, saving not only the nand partitions, but also the /data partition & the .android_secure mount point that reside on the internal sd. Restoring from a nand backup will restore the entire os, system & user settings & all installed apps.

Nvflash only backups the nand partitions. If you do use nvflash to do a backup & later do a restore of it, you must be sure to to a factory/data reset, wipe cache & wipe dalvik after the restore (so that you don't use possibly corrupt data/apps/settings left over from the previous installation).

For those situations that you can not enter CWM, I believe it is faster (and more reliable) to nvflash to the factory image, install CWM & then restore the nand backup (that includes all your apps & settings).

If you read post#42 on the thread Mike identified, you will note that rajeevvp does not recommend using nvflash to backup & restore for the reasons I noted. If you take another look through the thread you will see user "aabbondanza", that's is me.

Nvbackup does have it's uses though. I think it's a great tool to make a copy of your original image so that you always have a copy & especially for your original boot config table (bct - partition 2) & partition table (PT - partition 3).

Al
Hi Al,

I agree 100% that NVFlash isn't fully capable of restoring an existing ROM to 100% mirrored working order, but I don't think Mike is intending to use it in that way. I see where he is going with it by using it as a tool to create and restore a baseline like the stock 1.1 and 1.2 ROMs when jumping back and forth to other ROMs, but making it as close as possible to the ROM he is intending to update.zip to including select preinstalled apps that should carry over. CWM is definitely the tool to use if you want a mirror image of a point in time with a given ROM including all personal settings.

It will take a combination of things to create a workable product, but with a little effort, I believe this will work.

Mike,

I will play around with it tonight after running some errands. I will send you a PM and we can work from there.

My apologies to pixelrider for hijacking this thread. Though, it sounds like you are already dabbling with this NVFlash backup/restore angle.
 

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Hi Al,

I agree 100% that NVFlash isn't fully capable of restoring an existing ROM to 100% mirrored working order, but I don't think Mike is intending to use it in that way. I see where he is going with it by using it as a tool to create and restore a baseline like the stock 1.1 and 1.2 ROMs when jumping back and forth to other ROMs, but making it as close as possible to the ROM he is intending to update.zip to including select preinstalled apps that should carry over. CWM is definitely the tool to use if you want a mirror image of a point in time with a given ROM including all personal settings.

It will take a combination of things to create a workable product, but with a little effort, I believe this will work.

Mike,

I will play around with it tonight after running some errands. I will send you a PM and we can work from there.

My apologies to pixelrider for hijacking this thread. Though, it sounds like you are already dabbling with this NVFlash backup/restore angle.
Apologizes as well. I got the hint & will butt out, but if I'm reading what you said correctly, he wants to make a new base image with installed apps then for use when switching roms & still keep the installed apps after he switches roms! If that is the intention, good luck but I think that is inviting possible bricking, FCs or lockups. I've always been told to do as a minimum, a factory data reset before switching roms & if that is done installed apps & settings WILL NOT survive. Why not nvflash to stock w/cwm preinstalled, flash the rom you want & then use Titanium to restore your apps?
 

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Apologizes as well. I got the hint & will butt out, but if I'm reading what you said correctly, he wants to make a new base image with installed apps then for use when switching roms & still keep the installed apps after he switches roms! If that is the intention, good luck but I think that is inviting possible bricking, FCs or lockups. I've always been told to do as a minimum, a factory data reset before switching roms & if that is done installed apps & settings WILL NOT survive. Why not nvflash to stock w/cwm preinstalled, flash the rom you want & then use Titanium to restore your apps?
I can see your thought process, I have been in may scenarios jumping ROMs that take a complete wipe of existing data to correct, but unless I'm misunderstanding Mike's intentions, he has a few favorite ROMs that he bounces between, and why not skip a few steps as usually version updates don't require a full flatten and reload to stock. Some of these ROMs change regularly, but are only maintenance releases. I will try to get more definitive answer regarding what he is looking for as a finished product.

I hear you with the standard process to jump ROMs, but it would be nice to cut corners wherever possible. NVFlash is pretty quick compared to CWM restore. We'll see how it turns out.
 

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FW Developer
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Discussion Starter · #20 ·
Hey guys no problem. Yes I have been looking at using nvflash for backup & restore, among other things. I definitely don't have boat loads of experience with android, but I am slowly learning by hacking my way through.

My idea was to get a base Archlinux system installed with a working USB keyboard, and work things out from there. I think it would be possible to get a base image set up in nand memory space with a basic xorg install and maybe xfce. I am just not sure how to get going yet with the gtab. But by all means please use this thread to discuss possibilities that may be there for nvflash.
 
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