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Date: Sat, 12 Sep 2009 23:50:45 -0600
Message-ID: <51f3faa70909122250o59fcd174ifee4277ba25a20fe@mail.gmail.com>
Subject: Re: [PATCH] libata: Add pata_atp867x driver for Artop/Acard ATP867X 
	controllers
From: Robert Hancock <hancockrwd@gmail.com>
To: "Jung-Ik (John) Lee" <jilee@google.com>
Cc: Jeff Garzik <jgarzik@pobox.com>, Daniel Walker <dwalker@fifo99.com>,
       linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org,
       Grant Grundler <grundler@google.com>,
       Gwendal Grignou <gwendal@google.com>, Eric Uhrhane <ericu@google.com>
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On Sat, Sep 12, 2009 at 10:55 PM, Jung-Ik (John) Lee <jilee@google.com> wrote:
> I agree in that it's hard to measure/signify the additional overhead,
> since those io insts are already too slow.
> Anyways, the two extra "if"s and one PIO_MASK on every ioread/iowrite
> are pure overhead on top of in/out insts.

I don't think that any platform currently breaks if you use the
readX/writeX instead of ioreadX/iowriteX on iomapped MMIO addresses
(and there's certainly enough code in libata that does this), but the
API definition really expects that you should be using ioread/iowrite
so it would probably be best not to add any more of these..
--
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