Question on Linux vs Android kernels... sort of... and something else.

[hoabycsr]

I am just curious here. For the rk3188 I see at least 3 available different sources - the alok, the galland, and the omegamoon ones. I would like to know what the real difference is between these - just personal edits? I was able to build a functional android kernel for my MK908 from the alok sources rk3188Linux but have as of yet been able to duplicate my results with the other two. It took some source code editing to get it going for me in the first place and I notice those files are considerably different in the other releases. Just wondering what the deal really is. Also I saw on Galland´s git site that one of the updates pertained to mk908 power pin or something to that effect, but I can´t get those sources to build for mk908. It uses the lcdc0 output and most other sticks use lcdc1 and there´s some hardcoding in the sources for lcdc1 that makes it a pain to get it going.

Sorry for the long paragraph. My other question is this: If I´m going to build a kernel, how do I specify if it´s to boot ubuntu or android? I built a kernel for ubuntu on rk3066 that I am actually using on a MX1 to type this right now but really don´t know how to specify which it is for.. I just followed some instructions back then to get it going..., I have noticed the boot argument is different between the two and am wondering if that´s the only big difference. Or maybe the toolchain? I have no clue ; ; Anyways thanks for listening to my unorganized ramblings. Any info would be great!

[linuxium]

Re: Question on Linux vs Android kernels... sort of... and something else.

Hopefully here is some information to try and answer your questions. In terms of RK3188 source there is also the Rikomagic source which is available from my posting here (https://plus.google.com/u/0/10945117...ts/LWXfqzCseaE). Developers will typically clone the source into their own repository where they will then modify and enhance with new functionality and bug fixes. The three developer repositories you cite are excellent sources. Whilst each can answer directly, I recognize them for the following significant contributions: Alok has managed the Picuntu distro, Galland has incorporated the Mali GPU support and Omegamoon has provided CPU and GPU OC with each providing other fixes and functionality like wifi, fb fixes etc.. Each developer comments their code and "commits to git" (maybe see http://gitref.org/basic/ for further information) so it is possible to see what they have changed.

In terms of compiling, the source config I reference above is for the RKM IV and I provided a basic .config for running Ubuntu on a RK3188 board here (https://plus.google.com/u/0/10945117...ts/ii1vKzkA8G6) although it won't necessarily provide the board specific wifi and bluetooth functionality. Fundamentally it is the CONFIG_CMDLINE definitions in the .config that switch between Android and Ubuntu booting and obviously whether the compiled image is flashed as a kernel image or as a recovery image. In that post I've also included a sample shell file (needs localizing to your environmental) for compiling the source as an Ubuntu image together with the key files you need here (https://plus.google.com/u/0/10945117...ts/UBA47ksJpix). I've also posted some basic installation instructions here (https://plus.google.com/u/0/10945117...ts/jdUWmMKudJa) with a basic working Ubuntu image (see the comments within that post) to give you an initial Ubuntu environment.

From this combo of postings I hope there is sufficient explanation to enable anyone to compile both Android and Ubuntu images that can then run on their specific RK3188 board. I've tried to get everyone up and running with my posts so they can take it further rather than a turnkey solution. I hope this helps.

[hoabycsr]

Thank you very much! Extremely informative. I wish I could find a way to turn off UMP with the alok kernel... Unless the stick absolutely needs it, I´d rather get it out of the way. I have a theory that the video skippage problem is there.

[NixZero]

Thank you very much! Extremely informative. I wish I could find a way to turn off UMP with the alok kernel... Unless the stick absolutely needs it, I´d rather get it out of the way. I have a theory that the video skippage problem is there.

isnt ump needed for the gpu to access directly memory - aka for everything that requires the gpu, 3d and video acceleration included?

[hoabycsr]

isnt ump needed for the gpu to access directly memory - aka for everything that requires the gpu, 3d and video acceleration included?

You may be exactly right.. I haven´t learned enough yet. But that´s kind of what I´m talking about - getting it to switch to complete software rendering.. the unit should be fast enough to do it and it might be smoother.. But from what you say that may be impossible. I´m still learning, like I say.