[fedora-arm] ac100 kernel (Was: ARM F-14 Branched report: 20110823 changes)

[Gordan Bobic]

 On Mon, 05 Sep 2011 09:52:58 +0200, Mark Wielaard <mark at klomp.org> 
 wrote:

>> AFAIK we have no out of the box Fedora kernels for any ARM platform
>> anyway, so "out of the box" doesn't really apply. I am pretty sure 
>> not
>> enough of the required support has been upstreamed, otherwise we 
>> would
>> be using the upstream kernel. A lot of AC100 specific fixes are in
>> marvin24's tree on gitorius, and the base is from ChromeOS which is
>> trying to be compatible with Tegra2 paz00 boards that AC100 is based 
>> on.
>> Upstream path is thus somewhat complicated (Marc's (marvin24) AC100
>> tree, upstream to ChromeOS, which _may_ upstream to mainline but I
>> suspect like Android it will most likely be periodically forked and
>> maintained separately). Add to that the nvidia's kernel tree which 
>> is
>> separate again, and we occassionally include fixes from that (e.g.
>> Henning (woglinde) recently added in the patches to make the AES 
>> engine
>> work).
>>
>> This isn't really a discussion for the Fedora ARM mailing list. 
>> You'd
>> probably do better to take the discussion to the AC100 list on 
>> launchpad
>> and join the #ac100 channel on freenode. I doubt enough of the 
>> required
>> code will make it upstream any time soon.
>
> Yes, I got the impression the ARM kernel situation is a little
> fragmented :{

 Indeed, and a number of people are getting profoundly unhappy with the 
 state of the ARM support in the kernel.

> Just to be clear, for Fedora we would have to make sure
> the ac100 specific patches from the mavin24, chromeos and nvidia 
> kernel
> trees move towards the lkml/linus tree? Or can we pick up some of the
> patches and add them to the fedora spec file first for testing?

 Marc's tree is based on the ChromeOS tree, but includes some AC100 
 specific patches. I don't really know how feeding those upstream would 
 work - in theory it should be a case of feeding them back up to ChromeOS 
 tree, but whether ChromeOS changes filter through to mainline I don't 
 know. Like Android, I suspect it's a Google-maintained fork. I have no 
 idea what nvidia's mainline feeding policy is.

 Or to summarize - it's complicated and I don't know the answer.

> BTW. Would you happen to have (git) URLs for these trees to make it
> easier to see the diffs against mainline?

 As I said, it's more complicated than that, but you can have a look 
 here:

 http://gitorious.org/ac100
 http://nv-tegra.nvidia.com/gitweb/?p=linux-2.6.git;a=summary

 IMO the only sane approach to take at the moment is the pragmatic one 
 of using the kernel that works.

 Gordan