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Subject: Re: [PATCH] powerpc: remove fpscr use from [kvm_]cvt_{fd,df}
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From: Kumar Gala <galak@kernel.crashing.org>
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Date: Tue, 24 Aug 2010 00:47:05 -0500
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References: <m2hbinzlon.fsf@igel.home> <27922.1282523025@neuling.org>
To: Michael Neuling <mikey@neuling.org>
Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>,
	Andreas Schwab <schwab@linux-m68k.org>, kvm-ppc@vger.kernel.org
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On Aug 22, 2010, at 7:23 PM, Michael Neuling wrote:

>> Neither lfs nor stfs touch the fpscr, so remove the restore/save of =
it
>> around them.
>=20
> Do some 32 bit processors need this?=20
>=20
> In 32 bit before the merge, we use to have code that did:
>=20
>  #if defined(CONFIG_4xx) || defined(CONFIG_E500)
>   #define cvt_fd without save/restore fpscr
>  #else
>   #define cvt_fd with save/restore fpscr
>  #end if
>=20
> Kumar; does this ring any bells?
>=20
> (The addition of this predates even bitkeeper)
>=20
> Mikey

Not really.  However if the ifdef is as you say that seems wrong to me.  =
We should be using CONFIG_PPC_FPU or !CONFIG_PPC_FPU.  As both 4xx and =
E500 have variants w/FPUs.

- k=