Hi all,
Looking to build my first custom Rom and had some queries terminology-wise.
What is the relationship between the kernel and Google's android platform? For instance, is froyo tied to a specific kernel and is this in the source tree?
Second q: HTC release their kernel sources. Say I wanted to get a froyo build up for a device that currently only has eclair, would the procedure be to diff the HTC modifications against the vanilla version and then make the appropriate changes to froyo?
Third q: what makes a Rom specific to a device? Probably linked to first question...
Many thanks,
Martin
Sent from my HTC Wildfire using XDA App
The kernel is basically just a linux kernel with device specific drivers and such added. I've done a 'diff' between the Eris 2.6.29 kernel from HTC and the 'generic' 2.6.29 kernel from kernel.org. It's kind of neat to see the difference. I highly recommend you do that.
There are also device specific drivers in the file structure that the ROM needs in order to function.
What I've done is compile AOSP from source, compile the kernel from source, zip up the needed files/folders, signed the ROM, and then flashed it to test. If you look at Android Builder in my sig, you can figure out the difference between the Eris and your device. You'll have to change the kernel that gets downloaded, of course. And it really just gives you a basic ROM without the device specific drivers, so things will not work without figuring the rest out. Grab a stock ROM to get drivers, libs, etc. out of.
/system/usr/keychars & /system/usr/keylayout usually have the keyboard drivers, which are somewhat important.
Also in my sig is the SgtShultz ROM where I tried to make a usable ROM from as close to source as possible. You might get some ideas from there. I still haven't figured out how to get the audio to work. If I get that worked out, I'll actually start using the ROM daily and work out the rest!
Froyo seems to work with kernel versions 2.6.29+, btw.
Many thanks for this; it's given me a good set of places to start reading.
Just pulling down all the AOSP source as we speak, with the hopes of getting a basic build up in the near future
gnarlyc said:
What I've done is compile AOSP from source, compile the kernel from source, zip up the needed files/folders, signed the ROM, and then flashed it to test. If you look at Android Builder in my sig, you can figure out the difference between the Eris and your device. You'll have to change the kernel that gets downloaded, of course. And it really just gives you a basic ROM without the device specific drivers, so things will not work without figuring the rest out. Grab a stock ROM to get drivers, libs, etc. out of.
[...]
/system/usr/keychars & /system/usr/keylayout usually have the keyboard drivers, which are somewhat important.
[...]
Froyo seems to work with kernel versions 2.6.29+, btw.
Click to expand...
Click to collapse
A couple of questions on this front...
I can see, obviously, where to get the kernel source and needed drivers; I am, however, unclear as to where I should obtain AOSP drivers from (to go, for instance, in /devices/htc/buzz and/devices/htc/buzz-common). Can I extract these from my device? (or do I need to wait until they release Froyo and then extract them from a device running the newer build?) Where on the device should I be looking for this driver set?
Thanks again,
Martin
MartinEve said:
A couple of questions on this front...
I can see, obviously, where to get the kernel source and needed drivers; I am, however, unclear as to where I should obtain AOSP drivers from (to go, for instance, in /devices/htc/buzz and/devices/htc/buzz-common). Can I extract these from my device? (or do I need to wait until they release Froyo and then extract them from a device running the newer build?) Where on the device should I be looking for this driver set?
Thanks again,
Martin
Click to expand...
Click to collapse
For the most part, any Eclair drivers seem to work. At least that's what I have used for the Eris. 2.1 -> 2.2 isn't too big of a jump. I used drivers from a stock 2.1 ROM.
Look up vendor tree, vendor config, and 'extract-files.sh'. You'll see what people with other devices have done. I have yet to quite get the whole vendor tree thing worked out, but others have. You can just come up with a list of needed drivers to add to the 'extract-files.sh' script and just copy those files in manually. (That's what I have done.) This will get pretty close to making an AOSP build complete. However, it appears that actually using the vendor tree setup while compiling will get things 'right'. There appear to be some libs that will compile differently for different devices.
So, basically, if you compile AOSP without a vendor tree for your device, the build will be located in out/target/product/generic. (And, you can copy drivers in later while using the kitchen, but you might miss out on some AOSP stuff with device-specific changes.) If you use the vendor tree, it will be in /out/target/product/buzz and will contain the drivers that the 'extract-files.sh' script grabbed from your device along with custom compiled libs.
If you are able to get a working vendor tree for your device, it will be helpful to the entire community. They'll all be able to use it for their builds. I highly recommend doing that. Most groups use github or something similar to post the code.
I still have much to learn myself, and you are starting to reach my limit! Good stuff.
Hi,
Many thanks for your reply; to a degree, it's about knowing the terms to search for -- the extract-files.sh is a godsend for information that I would have otherwise missed.
Anyway, onwards to build a usable vendor tree
Best,
Martin
Greetings!
I need the kernel configuration files for the atrix2 since i want to compile a kernel module. I've tried the standard methods ( config.gz does not exist, and moto has turned off the compile options that allow us to extract it from a running kernel)
Do someone have access to one, or know how to get one - maybe from the source( it is not in the kernel/ source put out by moto, but maybe you know a way to extract it from the build source )
Thanks a ton
Manan
Hi I looked for sometime for answers but could not find anything relevant.
Looking to get the ftdi VCP drivers to install on Xoom. Which means I either have to compile a kernel or add them as a module. I can not for the life of me find the correct source tree.
I downloaded kernel 2.6.36.3 from google which matches my kernel version.
My kernel version on the tablet is 2.6.36.3-gb899258 .
When I cross compile the module and try to do an insmod its complaining about the magic version is different which leads me to believe that I have the wrong kernel.
Where can I get the right stock kernel?
If i can not find it there is another option to download the config.gz from the device and recompile another version of the kernel with native support for the ftdi drivers.. How do i just install just the kernel on the device? Is it a uImage bzImage and how do I just flash that?
cd
Thanks
edit:
scrap that ...
sorry, not really helpful in your case
I'm assuming you got your source from here? This is the link from the Android website:
git clone https://android.googlesource.com/kernel/tegra.git
If you decide to go the route of compiling another kernel source, the easiest way (and a good way to keep snapshots of various configs) would be to use Koush's AnyKernel to flash the kernel. I don't know anything about what you're trying to do but I hope that helps some.
Yep the code comes from there.....
I finally got it to work , I downloaded the stock kernel from google then when I make the modules I had to modify the Makefile to get it to match the kernel versions.
It seems to work for now...
Thanks for your help
So I've decided to give building Android a go, considering we've recently obtained the source code for the device in question (R1 HD) and no one else has done this yet for this device. I've been following this guide, since all the other guides I've found assume there is already a GitHub repo for your device. There's literally NOTHING out there regarding this device, aside from the kernel source we've obtained in the form of a .zip archive.
I've done everything up to and including pulling the 7.0.0 r1 source with the reop sync command, and I am now stuck on the Preparing to Build section. The first thing it talks about at this point is implementing proprietary binaries into my source. I have no idea where to find proprietary binaries for my R1 HD, let alone if they even exist out there to be implemented. Literally all I have regarding this device is the kernel source in a zip file. I can't find anything else out there nor do I really know what to look for.
Can anyone tell me what to do here? I've never compiled Android or even a kernel before, and I'd really like to get something out there for this device that others can base their work off of.
So ive been unfortunate so i cannot get A12 on my Xperia 1(J9110). But on dev.sony there is a compile guide for 12. I tought i will compile it from there.
But it cant be "that easy", i suppose it will have bugs that i need to fix but the last language i used was html in high school(yea yea get on with it).
My question is: if i compile it for myself can i use it as out-of-the-box or do i have to fix stuff or its an useless idea?
You would need to check if your device is listed in the devices.xml. If it is listed, there is a possibility that Sony has been updating the device tree, kernel and vendor blobs for android 12 and you could try compiling.
If it's not there, you won't be able to compile at all for your device without making a device tree, extracting vendor blobs and finding the right kernel for android 12, which would take a lot of work.
Griffin is there which means there is a chance. Still, can i use it out-of-the-box?