[fedora-arm] armv7hl requirements

[Jon Masters]

Folks,

I'd like to kick off a discussion about flags for ARMv7. My proposal
here is that we treat v7hl as an entirely different architecture, and
don't try any multi-arch kind of hacks (there isn't the established user
base for Fedora ARM to justify doing any of those things at the moment).

Things I think we should consider as a minimum:

*). Little endian (obviously, but worth stating) (l)
*). Cortex-A8 or higher fully compliant core(s)
*). ARM VFP3 hardware floating point (h)
*). ARM NEON Architecture
*). Thumb2 interworking
*). Your suggestion here?

I think we should build for ARM (as opposed to Thumb2) but we should
support interworking with Thumb2 code through the toolchain options. We
should then later consider implementing some Thumb2 optimization. It's
more armv7thl, but the (t) is implied since it's ARMv7 anyway.

Several folks have begun looking at toolchain bringup based on the F-15
toolchain applied to an F-13 userspace initially. But I'd like us to
discuss options/requirements for toolchains before we go too far.

Once I get some feedback, I'll be updating the wiki, along with some
more F-15 goals and (hopefully) generally useful stuff.

Jon.