Re: [Qemu-devel] [PATCH v3 2/2] Add Nios II semihosting support.

[Sandra Loosemore]

On 05/18/2018 03:35 PM, Sandra Loosemore wrote:
> On 05/18/2018 02:19 PM, Julian Brown wrote:
> > On Fri, 18 May 2018 21:52:04 +0200
> > Marek Vasut <address@hidden> wrote:
> >
> > > On 05/18/2018 09:23 PM, Julian Brown wrote:
> > > > This patch (by Sandra Loosemore, mildly rebased) adds support for
> > > > semihosting for Nios II bare-metal emulation.
> > > >
> > > > Signed-off-by: Julian Brown <address@hidden>
> > > > Signed-off-by: Sandra Loosemore <address@hidden>
> > >
> > > Is there some documentation for this stuff ? It looks interesting, but
> > > how can I try it here ?
> >
> > There's no documentation AFAIK apart from that the entry points are
> > the same as m68k, semihosting is invoked with "break 1", and r4/r5 are
> > used for passing arguments. I'm not actually sure how you can try this
> > stuff without our startup code or other infrastructure (that I'm pretty
> > sure we can't divulge). Sandra, any ideas?
>
> I don't see any reason why we couldn't contribute libgloss support, 
> except that I don't have time to write such a BSP right now.  :-(  I 
> recently did this for C-SKY, though, and the semihosting parts were just 
> a straightforward copy from the m68k port.

I've posted a patch with libgloss semihosting support for nios2 here:

https://sourceware.org/ml/newlib/2018/msg00610.html

I hope this is enough to unblock consideration of the corresponding QEMU 
patch set now.  Here's a link to the original patch posting:

http://lists.nongnu.org/archive/html/qemu-devel/2018-05/msg04571.html

-Sandra