[fedora-arm] arm software floating point support going forward

[Gordan Bobic]

 On Fri, 25 Jan 2013 10:22:23 -0600, Dennis Gilmore <dennis at ausil.us> 
 wrote:
> Hi all,
>
> I wanted to kick off a discussion, I think that with the work that
> Seneca is doing for armv6hl to support the Raspberry Pi most of the
> need for building sfp has gone away. I would like us to drop support
> for sfp in F19 that means that anyone running a kirkwood based system
> would get supported software updates for approximately 13 months from
> now. with cubie boards and other devices coming around that are cheap
> and more powerful and similar options I think there is little benefit
> to continuing to support sfp.
>
> Ive put in a request to get numbers of people using the arm and 
> armhfp
> portions of mirrormanager to get some idea of the number of users out
> there, though i suspect most arm are raspberry pi and people building
> in mock.

 I am inclined to agree.

 At the same time, however, this poses a few related questions?

 With essentially dropping armv5tel, does it make sense to replace
 it with what is very obviously going to be an arch with extremely
 short-lived support-worthyness? Or would it be better to just drop
 everything less than armv7hl and be done with it, and free up all
 the resources for focusing on the primary target?

 The focus question is particularly important considering that in
 the near future there will also be the 64-bit ARM arch to support.

 Or to put it another way - if armv5tel is drop-worthy, does
 what is essentially one device (the Pi) warrant the maintenance
 of an arch all by itself? If the answer to this is close to
 yes, then what about dropping armv7hl in favour of armv6hl as
 the only supported 32-bit ARM arch?

 What is the performance gap, hardware being equal, between:

 armv5tel -> armv6hl
 armv6hl -> armv7hl

 The answer to that question seems like it ought to factor
 into any decision made.

 Do any of the long standing issues of armv5tel (atomics?) go
 away when using armv6hl?

 Gordan