From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Austin S. Hemmelgarn" <ahferroin7@gmail.com>
Subject: Re: [PATCH RFC] reciprocal_divide: correction/update of the algorithm
Date: Tue, 14 Jan 2014 21:51:43 -0500
Message-ID: <52D5F7BF.7090407@gmail.com>
References: <20140113214249.GK6586@order.stressinduktion.org> <1389722825.31367.260.camel@edumazet-glaptop2.roam.corp.google.com> <52D58E6F.4050000@gmail.com> <1389729032.31367.262.camel@edumazet-glaptop2.roam.corp.google.com> <52D5A3DC.9030107@gmail.com> <1389739537.31367.273.camel@edumazet-glaptop2.roam.corp.google.com> <20140114232538.GD29887@pd.tnic>
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Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>,
	netdev@vger.kernel.org, dborkman@redhat.com,
	linux-kernel@vger.kernel.org, darkjames-ws@darkjames.pl
To: Borislav Petkov <bp@alien8.de>,
	Eric Dumazet <eric.dumazet@gmail.com>
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On 01/14/2014 06:25 PM, Borislav Petkov wrote:
> On Tue, Jan 14, 2014 at 02:45:37PM -0800, Eric Dumazet wrote:
>> Even on a Jaguar, the proposed alternative
> I don't know what Jaguar you guys are talking about but the Jaguar
> I know - Fam16h - has an int hardware divider:
>
> http://developer.amd.com/wordpress/media/2012/10/SOG_16h_52128_PUB_Rev1_1.pdf
>
> So all that talk about microcode is plain wrong. The hardware divider
> comes from Llano (F12h) so it must be some other Jaguar, maybe Bobcat.
>
> :-)
>
> If it is Bobcat, then it has a 1-bit per cycle ucode int divider.
>
Apologies, it does have a hardware divider, however it still only gets 2
bits per cycle.