[fedora-arm] ARMv7 rootfs/repository?

[Gordan Bobic]

Gordan Bobic wrote:
> Chris Tyler wrote:
>> On Wed, 2010-12-22 at 08:01 -0800, Andrew Burgess wrote:
>>> On 12/22/2010 06:30:13 AM, Chris Tyler wrote:
>>>
>>>> There is an expected performance gain with the switch to hardfp, but
>>>> that's a big challenge: you can't mix softfp and hardfp, so 
>>>> switching  to
>>>> hardfp is like bootstrapping an entirely new architecture.
>>> Since fedora has no problem mixing 32 and 64 bit executables it
>>> seems like there's alot of infrastructure already done for this.
>>> Just saying...
>>
>> It's not a Fedora infrastructure issue, the ABIs are incompatible. I
>> wish you could mix'n'match but that doesn't look possible.
> 
> What about kernel level FPU emulation? Is there such a thing? I could 
> have sworn there used to be something that could be used as such. And it 
> might be possible to make it quite transparent if it isn't required (so 
> you can always have it in the kernel). Have the kernel trap the 
> exception on the missing FPU instructions, save state, and then pass the 
> to an emulation library. When that returns, restore state and resume.
> 
> It would mean much slower performance than softfp on FPU-less hardware, 
> but it would allow for a transitional period where only VFP distro needs 
> to be maintained, which still works (albeit slowly) on a non-VFP processor.
> 
> Then again, I'm not volunteering to add such a feature to the Linux 
> kernel. :)

And just as I hit send, I found this:
http://netwinder.osuosl.org/users/s/scottb/public_html/notes/FP-Notes-all.html

No idea how relevant it might still be - the article is about 11 years old.

Gordan