ROMs BSP/SDK for NEC Renesas EMMA EV2 based Android devices, incl tablets for custom ROM

[gen-e]

This thread is for the discussion related to the NEC Renesas EMMA Mobile EV2 BSP/SDK.

Why I am posting here?
This thread was originally started at slatedroid.com by one member who had drawn my attention there.
The reason I was interested was because there was a community of Rena3/Opad users there who are having an active discussion of things related to Android tablets based on NEC Renesas EMMA Mobile EV2 chip. The community there are interested to port Cyanogenmod to Rena3/Opad or develop a custom ROM for the Rena3/Opad tablet.

Part of reason they want a custom ROM was because Rena3's firmware is badly implemented. Users have reported many bugs on it and the chip's performance is not fully optimized to utilize its two cpu either.

Their problem is that the source code of the NEC Renesas EMMA Mobile EV2 chip is not publically available, so they can't really do anything other than simple modifications.

However, I have previously stumbled upon the NEC Renesas EMMA Mobile EV2 BSP/SDK somewhere on the internet. With the help of interested developer, in slatedroid's SDK thread, I have confirmed that the BSP/SDK I have is the NEC Renesas EMMA Mobile EV2 BSP/SDK that they need.

I was planning to make it available on slatedroid.com but something I posted offended the moderators there..... And I was banned immediately without warning or recourse.
The slatedroid member who had originally invited me to slatedroid was also banned when he was trying to help me to get my account re-instated.

Hence, I have no choice but to find an alternative forum to continue the SDK thread from slatedroid.com
This forum seems to be a good choice, that's why I am posting here now.

You can visit the original thread here
http://www.slatedroid.com/topic/21660-sdk-possibly-on-the-way/

I have attempted to post this thread on androidtablets.net but this thread was deleted within 24 hours of posting (My account with androidtablets.net is not banned and still usable though....).
It was lucky that Google have a cache of this thread, so I don't have to retype the whole thing again....

Note: the same thread is posted at
BSP/SDK for NEC Renesas EMMA EV2 based Android devices, incl tablets for custom ROM
http://forum.xda-developers.com/showthread.php?p=18227034

 

[gen-e]

I have spend some time browsing this forum and also helped some of the members here before I started this thread.
I believe there are ROM developers here who may also be interested in this NEC Renesas EMMA Mobile EV2 BSP/SDK.
If not, I hope those member from Slatedroid.com would find their way here because I cannot make any post or even read slatedroid after I was banned.

With the help of fourgate from slatedroid, we have already uploaded the entire SDK/BSP on some file hosting web site.
I would be willing to post the links here if I receive confirmation that there are ROM developers who would be interested to work on this.

About the BSP/SDK
So far, what we know is that the NEC Renesas EMMA Mobile EV2 BSP/SDK I have obtained is dated around april 2011. There are a number of known bugs inside the BSP/SDK which have been fixed by some vendors by now (September 2011), e.g. a lot of bugs were fixed in our Gen-E tablet by our supplier and we are now (September 2011) using a firmware is now running a kernel which is dated in August 2011.

In order to port the latest version of Cyanogenmod or AOSP, i.e. Android 2.3 or later to NEC Renesas EMMA Mobile EV2 based tablet, you can expect that some work is required to update the kernel and fixed bugs that have already been fixed before...

In addition, we noticed that the BSP/SDK I have obtained is not complete but do contains the most important parts that you need. Yes, kernal source is there....

To get you started, this is the release notes of the BSP/SDK.
Download EMEVBSP_release_note_RC2.zip from Sendspace.com - send big files the easy way

Calling for ROM developers
If you are a ROM developer, capable of porting Cyanogenmod or AOSP to NEC Renesas EMMA Mobile EV2 based tablet, interested to work on this and want access to the source codes, please reply on this thread with the following information
1) State who you are
2) What do you intend to do with the file
2) What Renesas EMMA Mobile EV2 based device you currently own, if any. Or state none if you don't have one.
Once I see your post, I will sent u the download link via PM (please do NOT post the link I provide pubically but you are free to create a mirror copy of it elsewhere and post the link here.)

Why do I request these information?
So everyone knows who is trying to work on this because at present (17th October), because there are too few developers working on this and we would like to be able to contact them to seek update or have them available to help out other developers who are also working on this. I only know one developer, who found me through these threads, is actively working on this

In order to keep the BSP/SDK publically available, after you have downloaded the BSP/SDK, I would like to ask you to help us upload, host the file somewhere else and post a reply here to share the download link. Then, I will update the download link on this post here.

Public repository
To help with collaboration, I think we would need a repository to store/merge the code from different developers.
I am not a developer and I can't help on this. So, I would need a volunteer to manage this......(anyone?)
Or you have a suggestion where we can put the modified source code?

You can look here for the code.

I organized it in three repositories based around the tar.gz files in the SDK.

If someone wants to reorganize that's fine by me.

https://github.com/cAPSLOCK7

 

[gen-e]

Useful informations related to this
For those ROM developers who do NOT have a NEC Renesas EMMA Mobile EV2 based tablet, if you have proven yourself that you are genuinely making contributions towards Cyanogenmod or ASOP build for NEC Renesas EMMA Mobile EV2 based tablet. We are willing to provide you with our Gen-E tablet at a discounted price. Please PM me on this matter after you made some contribution here.

 

[gen-e]

(reserved for additional information)

 

[gen-e]

(I am posting this on behalf of a chinese developer. This is his finding, not mine. He has Haipad M9.)
Renesas EMMA EV2 device internal partition and ROM flashing logic

Recommended: The flashing method that uses VOL- will preserve the existing apk installed as well as other user data.

PS: this document only refers to the newer model, older model of the unit should be similar (The author had worked these out using his HaiPad M9).

Device partition explanation:
Renesas EMMA EV2 use iNand for internal storage, this is a type of new storage media using MMC connector (same connector as SD card), it can be viewed as an internal SD card. MMC connector is mounted as device mmcblk*p*, the first * means the device number, starting from 0. The second * means partition number, starting from 1.

Therefore:
iNand device becomes mmcblk0, the corresponding SD card becomes mmcblk1.

iNand is being divided into 7 partitions, as described below:
1) mmcblk0p1--->uboot, used to load instructions to start the system, equivalent to the BIOS of the computer. If this portion is damaged, the device will not boot at all. The vibration when the device starts is also specified here.
2) mmcblk0p2--->kernel, the place where the Linux kernel resides.
3) mmcblk0p3--->a small scale file system, when you press VOL- to boot, it uses the file system in here. (kernel is only the core, when booting, it still requires the file system support, GUI, etc are all placed here.)
4) mmcblk0p4--->expansion. Since only maximum of 4 partitions are allowed for the main partition, therefore this region is classed as expansion partition.
5) mmcblk0p5--->android-fs. The files loaded during normal booting are loaded from here.
6) mmcblk0p6--->data partition. The apk that the user installed are located in this partition. When you press VOL- into recovery and select “Wipe data”, this is the partition that is cleared.
7) mmcblk0p7--->user storage for music, video, etc…

VOL- upgrade principle:
When you press VOL- to boot, the CPU will start reading the data located in mmcblk0p1(uboot) partition, uboot runs and then load the kernel in mmcblk0p2, and then load the file system in mmcblk0p3, and then execute upgrade recovery program. Recovery means the yellow interface, which contains the upgrade, WIPE data, etc operations.

When you execute “upgrade system from SDcard” operation, recovery will check the upgrade file (compute its MD5 value and compare with update.conf), if they are the same, it will execute the upgrade instructions, upgrade method is:
uboot4.bin--->copy document to mmcblk0p1 partition and replace existing uboot
uImage4--->copy document to mmcblk0p2 partition and replace existing kernel
android-fs4.tar.gz---> clear content from mmcblk0p5 partition, and then uncompress the document into mmcblk0p5 partition to update the android-fs
Note: if wipe data is not executed, the currently installed apk will be preserved. However, if the changes as a result of the upgrade are too much, it may cause strange problems to appear. To fix these problems, just boot using VOL- again and perform wipe data.

VOL+ upgrade principle:
If the user upgrade incorrectly, then VOL- would not boot the device. Depending on the circumstances, these may occur:
1) After the device is turned on, the power LED is on but no vibration: This definitely means error in the mmcblk0p1 partition. Such situation means you must use SD card to re-flash the ROM.
2) The device vibrate when it is turned on, however there is no LOGO, the screen is black: this may means there is some error in mmcblk0p or mmcblk0p5. If you press VOL- and can enter recovery, that means the error is in partition mmcblk0p2.
3) The device vibrate when boot and also able to show LOGO and Android booting animation, but it keeps looping/restarting, this means something is wrong with mmcblk0p5 partition, if so, use VOL- to upgrade again.
When VOL+ is pressed when booting, the CPU will detect it and will use FAT file system to load mmcblk1p1 (SD card) partition’s sdboot.bin and uboot-sd.bin, if the loading is successfully, then it will also load uImage4 and cramfs4 file, uImage4 means the Linux kernel, if the loading is successful, then it will use cramfs4 as the file system and run the entire OS. After the OS is running, it will execute install.sh file, follow the instructions in install.sh and repartition mmcblk0 partition, and also copy uboot4.bin, uImage4, cramfs4.tar.gz, android-fs4.tar.gz into their respectively partitions (mmcblk0p*).

The difference with VOL- is that all the files are retained on the SD card, if the device is bricked, this method can be used to re-flash the ROM. Due to the use of FAT file system, FAT only support 2GB or smaller capacity, therefore, you need to use a 2GB or smaller SD card formatted into FAT for this operation. If your SD card is larger than 2GB, please refer to the upgrade document’s instruction and partition your SD card into 2GB or smaller.

install.sh file analysis:
1) Nothing interesting at the beginning, mainly to check if certain files exist or not.
2) Starting from fdisk, this portion contains instructions to repartition mmcblk0 (need linux foundation, you can search for linux fdisk online). The partition size that user want to change is also located here. From here onward, you can see several place with +xxM, these configures the size of each partition. E.g. +5M means this partition is 5MB. The order inside is :
+5M: mmcblk0p1, better don’t change the size of this partition
+10M: mmcblk0p2, for the kernel. Because the uImage4 is only 4.xM, this partition maybe shrinked slightly.
+50M: mmcblk0p3, for cramfs4.tar.gz. Since the cramfs4.tar.gz stored here is uncompressed, do not shrink this partition without serious consideration.
+250M:mmcblk0p, stores android-fs.
+750M:mmcblk0p6 stored data. If the user needs to install more apk, can increase the size of this partition, e.g. 1GB, etc…
Others: the rest of the space are devoted to storing video, music, etc
3) The rest of the code aren’t interesting, mainly to copy files into mmcblk0