Subject: Re: VFP support?
To: Matt Thomas <matt@3am-software.com>
From: Chris Gilbert <chris@dokein.co.uk>
List: port-arm
Date: 09/13/2007 00:19:58
Matt Thomas wrote:
>
> I have a few ARMs with real VFP. What is the state of VFP support in
> NetBSD?
> Does it work? Should it work?
I don't think it's supported at the moment, I don't remember anyone
adding code to save the VFP regs on a context switch which is probably
the main bit of kernel work needed.
gcc appears to have vfp support as a vfp file does exist:
src/gnu/dist/gcc4/gcc/config/arm/vfp.md
possibly enabled by using:
-mfpu=vfp
Also I note that sys/arch/arm/include/float.h has some #ifndef __VFP_FP__
Is it a full vfp implementation, or is it like the original floating
point where the some instructions are in hardware, and some are emulated?
So I guess it's been thought about, but as your possibly the first
person with a VFP capable chip you get the fun of making it work :)
Thanks,
Chris