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Subject: Re: fsqrt
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "tiejun.chen" <tiejun.chen@windriver.com>
Date: Fri, 07 Jun 2013 18:53:53 +1000
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Cc: Xie Shaohui-B21989 <B21989@freescale.com>,
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On Fri, 2013-06-07 at 15:46 +0800, tiejun.chen wrote:
> On 06/07/2013 03:41 PM, Benjamin Herrenschmidt wrote:
> > Another question...
> >
> > Do you guys happen to have a patch to emulate fsqrt in the kernel ?
> 
> Seems this is already emulated:
> 
> arch/powerpc/math-emu/fsqrt.c
> 
> You can enable CONFIG_MATH_EMULATION to try.

Is math emu expected to work at all on top of a real FPU ? I though it
didn't ... maybe I'm wrong.

Cheers,
Ben.