From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Neuling <mikey@neuling.org>
Date: Wed, 25 Aug 2010 01:34:12 +0000
Subject: Re: [PATCH] powerpc: remove fpscr use from [kvm_]cvt_{fd,df}
Message-Id: <10192.1282700052@neuling.org>
List-Id: <kvm-ppc.vger.kernel.org>
References: <m2hbinzlon.fsf@igel.home> <27922.1282523025@neuling.org>
	<1282626718.22370.505.camel@pasglop> <32250.1282626925@neuling.org>
	<1282699836.22370.566.camel@pasglop>
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org, Andreas Schwab <schwab@linux-m68k.org>, kvm-ppc@vger.kernel.org, Paul Mackerras <paulus@samba.org>

In message <1282699836.22370.566.camel@pasglop> you wrote:
> On Tue, 2010-08-24 at 15:15 +1000, Michael Neuling wrote:
> > > > Do some 32 bit processors need this? 
> > > > 
> > > > In 32 bit before the merge, we use to have code that did:
> > > > 
> > > >   #if defined(CONFIG_4xx) || defined(CONFIG_E500)
> > > >    #define cvt_fd without save/restore fpscr
> > > >   #else
> > > >    #define cvt_fd with save/restore fpscr
> > > >   #end if
> > > > 
> > > > Kumar; does this ring any bells?
> > > 
> > > I don't see anything in the various 440 docs I have at hand that would
> > > hint at lfd/stfs adffecting FPSCR.
> > 
> > The way the ifdefs are, it's the other way around.  4xx procs don't need
> > to save/restore fpscr and others do.
> 
> Right, my bad. In any case, Paulus reckons it's all his mistake and we
> really never need to save/restore fpscr.

ACK :-P

Mikey

From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <mikey@neuling.org>
From: Michael Neuling <mikey@neuling.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: remove fpscr use from [kvm_]cvt_{fd,df}
In-reply-to: <1282699836.22370.566.camel@pasglop>
References: <m2hbinzlon.fsf@igel.home> <27922.1282523025@neuling.org>
	<1282626718.22370.505.camel@pasglop> <32250.1282626925@neuling.org>
	<1282699836.22370.566.camel@pasglop>
Date: Wed, 25 Aug 2010 11:34:12 +1000
Message-ID: <10192.1282700052@neuling.org>
Cc: linuxppc-dev@ozlabs.org, Andreas Schwab <schwab@linux-m68k.org>,
	kvm-ppc@vger.kernel.org, Paul Mackerras <paulus@samba.org>
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In message <1282699836.22370.566.camel@pasglop> you wrote:
> On Tue, 2010-08-24 at 15:15 +1000, Michael Neuling wrote:
> > > > Do some 32 bit processors need this? 
> > > > 
> > > > In 32 bit before the merge, we use to have code that did:
> > > > 
> > > >   #if defined(CONFIG_4xx) || defined(CONFIG_E500)
> > > >    #define cvt_fd without save/restore fpscr
> > > >   #else
> > > >    #define cvt_fd with save/restore fpscr
> > > >   #end if
> > > > 
> > > > Kumar; does this ring any bells?
> > > 
> > > I don't see anything in the various 440 docs I have at hand that would
> > > hint at lfd/stfs adffecting FPSCR.
> > 
> > The way the ifdefs are, it's the other way around.  4xx procs don't need
> > to save/restore fpscr and others do.
> 
> Right, my bad. In any case, Paulus reckons it's all his mistake and we
> really never need to save/restore fpscr.

ACK :-P

Mikey