Hi,
I'm playing with ROM building recently and I when building 2.1 ROM, everyone say "We can't fix X issue because we don't have kernel sources".
I was shocked seeing all great hardware support is on the Eris leak based ROMs.
Why thoses ROMs have better hardware support ? I thought when we port a ROM, we take a working boot.img (kernel + drivers) and the new system.img together. So if I'm not wrong, what make thoses ROMs better ?
I'm probably missing some key understanding. If you can help me, I'll really appreciate.
Regards,
mik
Eris is basically Verizons Wireless's re-branded version of Hero.
The hardware and everything is same, just the physical appearance.
So our new kernel base is now this one ?
I'm asking because I'm building AOSP (cyanogenmod) ROMs so if this new kernel+drivers is the way to go, I'll start wirking with this as base and not the old HERO2.1 one
mik- said:
So our new kernel base is now this one ?
I'm asking because I'm building AOSP (cyanogenmod) ROMs so if this new kernel+drivers is the way to go, I'll start wirking with this as base and not the old HERO2.1 one
Click to expand...
Click to collapse
The kernel of the Eris is different to the Hero, they are still using the old kernel on the Eris port
l0st.prophet said:
The kernel of the Eris is different to the Hero, they are still using the old kernel on the Eris port
Click to expand...
Click to collapse
So why the hardware support is so good ?
hardware driver...
Isn't all of this supposed to be open source anyway? Like, if the official kernel has better hardware support, why isn't it in the Android Open Source Project (AOSP), if Android is GPL-licensed Free Software? Is there a violation of the GPL going on here?
FunkTrooper said:
Isn't all of this supposed to be open source anyway? Like, if the official kernel has better hardware support, why isn't it in the Android Open Source Project (AOSP), if Android is GPL-licensed Free Software? Is there a violation of the GPL going on here?
Click to expand...
Click to collapse
Because the official kernel isn't officially available, it's still technically in development. They are under no obligation to release it until they release it to the public, by which point we will have it anyway
FunkTrooper said:
Isn't all of this supposed to be open source anyway? Like, if the official kernel has better hardware support, why isn't it in the Android Open Source Project (AOSP), if Android is GPL-licensed Free Software? Is there a violation of the GPL going on here?
Click to expand...
Click to collapse
Common misconception number 1 - Android is *not* licensed under the GPL, it is licensed under the Apache Software License (ASL). This license is not a copy left license so OEMs who modify the Android source are under absolutely no obligation to make their modified source code available.
However, the Linux kernel upon which Android runs is licensed under the GPL, so HTC must provide the source for any *shipping* software that uses said kernel. Since HTC have not officially released their version of Android 2.1, again they are under no obligation to supply kernel source. The second that they official ship the update, this changes and they are obliged under the terms of the GPL to make the kernel source available.
Regards,
Dave
And I hate to be a complete noob, but are these drivers that provide the nice hardware support part of the kernel?
If not, what difference would it even make if we didn't have the official kernel sources?
Since the Eris has the exact same hardware as the Hero, why can't we use the same kernel as the Eris rom ?
Latoc said:
Since the Eris has the exact same hardware as the Hero, why can't we use the same kernel as the Eris rom ?
Click to expand...
Click to collapse
Because it isn't the same hardware.
The Eris is close, but not identical to the Hero. The major difference is it's CDMA, not GSM. And, it uses touch buttons instead of physical buttons.
Other than those two, I'm not sure if there are any other significant differences. Point being that those differences are enough to warrant a different kernel.
e.japonica said:
hardware driver...
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Click to collapse
So if I understand correctly, the Eris leak based ROM use the old kernel (2.6.29) but newer hardware drivers so my question is correct ... Should we use any Eris based ROM as base to make new AOSP ROMs ?
This way, we will keep the old kernel but new drivers ...
Please correct me if I'm wrong.
mik- said:
So if I understand correctly, the Eris leak based ROM use the old kernel (2.6.29) but newer hardware drivers so my question is correct ... Should we use any Eris based ROM as base to make new AOSP ROMs ?
This way, we will keep the old kernel but new drivers ...
Please correct me if I'm wrong.
Click to expand...
Click to collapse
Really, it's all going to change when we get to official Hero 2.1 ROM (and kernel,) because that's what we'll be using very soon (if we're to believe the hype about 2.1 finally coming this month.)
As for right now, it's up to you. If I were to start working on a ROM, I would use the Eris dump, although you'll have to change to the official kernel in a couple weeks anyway.
I'm not really sure what to say about using "the old kernel but new drivers. I'm not into kernel dev myself, but what's "old" and what's "new" is going to change soon anyway, so I don't think it matters too much at this point.
EDIT: Let me correct myself: If you're going to make an AOSP ROM, you won't use the Eris *ROM* as the base, you'd just use the kernel and drivers. The rest of the system would not have any HTC-ness attached to it (no Sense/HTC Mail/etc), so you'd actually use an AOSP image instead of an Eris/Hero image.
craig0r said:
Really, it's all going to change when we get to official Hero 2.1 ROM (and kernel,) because that's what we'll be using very soon (if we're to believe the hype about 2.1 finally coming this month.)
As for right now, it's up to you. If I were to start working on a ROM, I would use the Eris dump, although you'll have to change to the official kernel in a couple weeks anyway.
I'm not really sure what to say about using "the old kernel but new drivers. I'm not into kernel dev myself, but what's "old" and what's "new" is going to change soon anyway, so I don't think it matters too much at this point.
EDIT: Let me correct myself: If you're going to make an AOSP ROM, you won't use the Eris *ROM* as the base, you'd just use the kernel and drivers. The rest of the system would not have any HTC-ness attached to it (no Sense/HTC Mail/etc), so you'd actually use an AOSP image instead of an Eris/Hero image.
Click to expand...
Click to collapse
Yeah, I know. Sorry to not being clear enough. When we build AOSP build, we take an existing ROM to extract kernel and drivers to make the AOSP code working. When I say take Eris leak based Roms as base, I mean just the kernel/drivers part. I know the whole system will not be taken into account.
Eris and AOSP 2.1 roms
After looking at the previous 2.1 roms that were being used to cook and the Eris now being used by everyone, although both being 2.1 they do appear to be different versions of the same product
The Eris appears to be a cut down version of the ASOP 2.1 version, the mail app is still based around the 1.5 version HTC mail, rather than the mail app that is on ASOP which gives you global address list search etc on exchange, and new features on incoming mail for normal mail accounts.
Are features like this built into the kernel themselves ? or things like mail, dialers just apk files
A few forums are now reporting that the new official version of 2.1 for the hero will be a basic version compared to the versions running on desire and nexus. Which would be a disappointment
Hi all,
I am really interested to use, if there is a ROM based on Xperia Arc.
So far, I have tried to get some apks to work on Oxygen, an existing AOSP ROM.
ArcXygen
I have just found the latest dump file of Xperia Arc. Here
I know that I am really incapable to port those stuff over. I have no knowledge about Linux and only know very very limited C language - I can just barely able to work well with pointers.
But I will want to give it a try, if it's not too hard.
I know copy everything from the dump and flash it through will surely won't work. What is the cause of this usually? (incompatible library?) As far as I see, Arc ROM seems quite Vanilla though.
And I will really be glad if there is a developer who finds this idea interesting (an Arc ROM - not another stock Sense ROM!!)and takes over to do it. It will surely be 6,000 times faster than what I can do.
Any help/comment/advice will be highly appreciated. Thank you.
Hi,
I would like to learn how to create my own custom ROM. Any reference you have on the topic would be great. I have successfully built my own kernel from source and have made a guide here: http://forum.xda-developers.com/showthread.php?t=1516051
Now I would like to build my own custom ROM. I noticed that when I downloaded the kernel source code from Samsung it also included the platform source code. I have read somewhere that I wouldn't be able to compile the Stock ROM just because a lot of the stuff is proprietary (like touchwiz). If this is the case, how are developers including the proprietary stuff?
Is it possible to build stock ROM from source?
Are custom ROMs more about tweaking existing configurations and apps, as oppose to compiling from scratch?
Thanks for helping a noob. I really want to learn the stuff.
I am trying to learn rom development because I feel bad that my device (LU6200) gets very little attention in the forums. I figured might as well learn something and help the rest of the poor souls with the same model as mine.
So if anyone would be so kind:
1.) What's the relationship between the kernel and rom?
2.) Will adopting a compatible kernel make a non compatible rom (due to minor model differences) work? I'm talking about about a LU6200 kernel for a CM9 P930 rom.
3.) What applications/drivers control the sim card access and network compatibility? - My phone (and sim) seems to run ok with the Canadian restore of a P930, but HO!NO! and other modded roms crashes my phone whenever I input an APN and attempt data connection.
Thanks in advance for any kind soul out there. Plus, I would not mind reading through pages of tutorials if anyone can link some.
edge808 said:
I am trying to learn rom development because I feel bad that my device (LU6200) gets very little attention in the forums. I figured might as well learn something and help the rest of the poor souls with the same model as mine.
So if anyone would be so kind:
1.) What's the relationship between the kernel and rom?
2.) Will adopting a compatible kernel make a non compatible rom (due to minor model differences) work? I'm talking about about a LU6200 kernel for a CM9 P930 rom.
3.) What applications/drivers control the sim card access and network compatibility? - My phone (and sim) seems to run ok with the Canadian restore of a P930, but HO!NO! and other modded roms crashes my phone whenever I input an APN and attempt data connection.
Thanks in advance for any kind soul out there. Plus, I would not mind reading through pages of tutorials if anyone can link some.
Click to expand...
Click to collapse
1. The kernel is the interface between your phone's OS, and its hardware components. It presents the components to the OS and tells it what each component does.
2. Using a p930 rom with a modified lu6200 kernel should work, but a p930 rom that flashes a p930 kernel will cause problems due to a change in hardware layouts on each phone.
3. Sorry, not sure. Try apn backup/restore.
Sent from my LG-P930 using XDA
hi,man you're not alone.!i also tried hard to port CM9 for 6200. But with no help from some experts, it's really hard for beginners like us.so i eventually gave up. what i learned from my messing with the rom is there's a difference in flash layout. i tried to take the ramdisk part from 6200 and repack it with cm9's kernel.sadly that doesn't work. flashing only the cm9's system part will cause endless boot loops.
@hereric
Thanks for the answers. That helped cleared things a bit. I've also started reading on compiling kernels myself but it seems a lot more complicated than I had anticipated. But I'm patient. I'll read up some more.
Is it possible compare the source of the GB kernels of a lu6200 and a p930, figure out the differences, and then modify the p930 kernel so it's compatible with the lu6200 hardware? I mean the kernels shouldn't be too far apart considering they are nearly identical in hardware.
@freefall12
Have you tried flashing an CM9 build and then follow it up with HO!NO! LU6200 Overclock kernel?
Hi,
Can someone explain why it's not possible to use a AOSP/AOKP kernel with SonyEricsson based ROM's and vice versa? I know it's not possible but I'm interested in the technical reason.
Thanks,
Svanteson
Google about how a kernel works and what it is, then you will understand better.
A kernel is like a "connection bride" in your system.
All rom systems are not the same, therefore a kernel for aosp wont work on sony rom because it will "connect" wrong
Typed down from the sky with sexy LT15i
TheHaso said:
Google about how a kernel works and what it is, then you will understand better.
A kernel is like a "connection bride" in your system.
All rom systems are not the same, therefore a kernel for aosp wont work on sony rom because it will "connect" wrong
Typed down from the sky with sexy LT15i
Click to expand...
Click to collapse
I know how a kernel works and what it is. I know all ROM's are not the same. I know a kernel for aosp won't work on sony ROM.
What I asked for was the technical reason for it not to work. "It will connect wrong" is not a very good technical explanation...
Maybe it's due to the kernel modules? I guess they are located in the /system partition and compiled for a specific kernel version?
BR/Svanteson
What would be weird: kernels working for several completely different phones. Why would a kernel like franco kernel, made for the Galaxy Nexus, work with Xperia Arc? Obviously the kernel has configurations and optimizations for a certain set of hardware, and if you completely switch the hardware it doesn't make sense to expect functionality.
bajsmumsaren said:
What would be weird: kernels working for several completely different phones. Why would a kernel like franco kernel, made for the Galaxy Nexus, work with Xperia Arc? Obviously the kernel has configurations and optimizations for a certain set of hardware, and if you completely switch the hardware it doesn't make sense to expect functionality.
Click to expand...
Click to collapse
I'm not talking about different hardware. I'm taking about an AOSP/AOKP-kernel built for Arc/s that don't work with a Sony Ericsson based ROM for Arc/s and vice versa.
svanteson said:
I'm not talking about different hardware. I'm taking about an AOSP/AOKP-kernel built for Arc/s that don't work with a Sony Ericsson based ROM for Arc/s and vice versa.
Click to expand...
Click to collapse
Is there even such a thing as an AOKP kernel? Arccording to their own website, AOKP is "a custom ROM distribution for many Android devices". If you're asking why some ROMs don't work with some kernels, then the answer is simply that one or the other has dependencies/ways of doing things that are not supported by the other.
Well, I'm not interested in the simple answer because that I already know.
I have used a debian kernel with Suse on a x86 PC. Stupid thing to do, I know. It was a customer who wanted to try that in a specific setup.
But it booted up. Why is not a Sony Ericsson based ROM booting on an AOSP kernel?
Is it due to different kernel module versions, boot params and/or other things?
Perhaps I should post this in the devel forum instead?