Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 10 Jun 2004 12:14:30 -1000
From:      juli mallett <jmallett@FreeBSD.org>
To:        Ralf Baechle <ralf@linux-mips.org>
Cc:        freebsd-mips@FreeBSD.org
Subject:   Re: Some MIPS status goodies.
Message-ID:  <20040610221430.GA26579@FreeBSD.org>
In-Reply-To: <20040610160207.GB32315@linux-mips.org>
References:  <Pine.LNX.4.33.0406101040240.2858-100000@servww6.ww.uni-erlangen.de> <20040610090712.GA71925@FreeBSD.org> <20040610160207.GB32315@linux-mips.org>

next in thread | previous in thread | raw e-mail | index | archive | help
* Ralf Baechle <ralf@linux-mips.org> [ Date: 2004-06-10 ]
	[ w.r.t. Re: Some MIPS status goodies. ]
> On Wed, Jun 09, 2004 at 11:07:12PM -1000, juli mallett wrote:
> 
> > R10K and IP28 support are probably a ways away, but I'm interested
> > in supporting these systems and more.  Right now it's easiest to start
> > with the, much simpler, R4400 Indigo2 I have here, and get a good base
> > of this stuff, then move into supporting the more modern and complex
> > CPUs and machines - but be assured I am taking them into account!
> 
> R10000 in non-coherent systems (Indigo 2 R10000, O2) is a rather hard to
> use processor due to unwanted behaviour of speculative execution that
> leads to memory corruption.  The workarounds are fairly complex; efficient
> solutions involve compiler modifications.

Yeah, I read about the compiler mods SGI had to make, with accessing
the stack as a barrier...  It sounded like that was only for the
kernel though, yeah?

> That said, the R10000's is resolving all hazards in hardware and does
> almost the entire coherency in software so in a saner system such as
> the Origin it's a breeze.

Right.

juli.
-- 
juli mallett.  jmallett@freebsd.org.  adrift in the pacific.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20040610221430.GA26579>