From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 0/3] x86_64, sfc: 128-bit memory-mapped I/O
Date: Tue, 21 Aug 2012 18:38:24 -0700
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References: <1345598275.2659.71.camel@bwh-desktop.uk.solarflarecom.com>
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Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, netdev@vger.kernel.org,
	linux-net-drivers@solarflare.com, x86@kernel.org
To: Ben Hutchings <bhutchings@solarflare.com>
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On 08/21/2012 06:17 PM, Ben Hutchings wrote:
> Current Solarflare network controllers have 128-bit memory-mapped
> registers which are normally accessed through a series of I/O
> operations.  However, it is also possible to access them with a single
> MOVAPS instruction on x86_64, and this is measurably faster as it
> requires only one PCIe transaction.

Also, have you considered doing this with write combining instead?

	-hpa