Fiasco.OC-UX on MIPS?

Paul Boddie paul at
Tue Sep 10 12:42:36 CEST 2019

On Monday 9. September 2019 23.53.13 Adam Lackorzynski wrote:
> On Fri Aug 30, 2019 at 13:43:10 +0200, Paul Boddie wrote:
> > 
> > So maybe the approach for initialising t9 could be reviewed so that it is
> > not toolchain-specific. Here, as before, I ended up doing something like
> > this:> 
> > _start:
> >     lui $25, %hi(_realstart)
> >     ori $25, $25, %lo(_realstart)
> > 
> > _realstart:
> >     ...
> Thanks for the update!
> Indeed it seems to work for me without any adjustments both with mips32
> on malta and with mips64 on the boston platform (both with a
> pretty recent QEMU). I probably using the "wrong" compiler. I'll try to
> follow up here once sid's cross compilers are installable again.

At the moment, I'm using the native compiler in the Stretch (oldstable) 
version of Debian, but I first had this problem with the Sid (unstable) cross-
compilers about two years ago, and I imagine that there is something about 
Debian's compilers or even generic GCC which is different from whatever you 
are using. (I should perhaps check the output of my Buildroot cross-compilers 
to see what they actually produce, too.)

Still, the compilers - of both kinds - in Stretch (oldstable) and Buster 
(stable) should be usable. I haven't done much with the unstable cross-
compilers in a couple of months.


P.S. I have also been pursuing the user mode kernel work, which for various 
reasons has been proceeding slowly. Aside from errors I have introduced 
myself, there have been plenty of challenges getting things like data 
structures allocated and initialised, and it feels like guesswork at times.

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