On Fri, Jan 25, 2013 at 1:10 PM, Nicolas Pitre <nico(a)fluxnic.net> wrote:
On Fri, 25 Jan 2013, Josh Boyer wrote:
> On Fri, Jan 25, 2013 at 11:22 AM, Dennis Gilmore <dennis(a)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.
> I'm not overly familiar with arm, but from a kernel standpoint you might
> be able to enable floating point emulation. That would let you run the
> hardfp binaries on the boards without an FPU.
No, you can't.
The only FP emulation the ARM kernel provide is for the antique FPA
instruction set that almost never got implemented in hardware, except
for a few exceptions that Linux never supported anyway.
Ah. See, that would be where I point back to me knowning almost nothing
about ARM ;).
All modern EABI compliant binaries are using the VFP instruction
and the only thing the kernel implements is the processing of
exceptions for them. To have a full VFP emulation support in the
kernel, significant development effort would be needed.
I find this slightly interesting to be honest. In the embedded powerpc
world, math emulation is used as a last ditch effort but it does exist.
I would have thought the proliferation of ARM devices would generate some
amount of interest in getting similar support in-kernel, but apparently
Anyway, I'm not opposed to dropping a kernel variant at all. Makes some