From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: Compact Flash performance... Date: Thu, 31 May 2007 18:43:46 -0400 Message-ID: <465F4FA2.8030200@rtr.ca> References: <6278d2220705301510y2d81f69eu38fb778d32de05e1@mail.gmail.com> <465E3FF0.9010709@rtr.ca> <6278d2220705310222rde9ad28ndfd8feced84a3c6f@mail.gmail.com> <465EBE20.6090803@rtr.ca> <6278d2220705311025q6ee030e2kd44b7302a50ac902@mail.gmail.com> <465F360D.6020603@rtr.ca> <6278d2220705311439x40f7b1c1l7cef54acd2e8fcea@mail.gmail.com> <465F4D4E.6050305@rtr.ca> <465F4E20.5080503@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([64.26.128.89]:4940 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbXEaWnu (ORCPT ); Thu, 31 May 2007 18:43:50 -0400 In-Reply-To: <465F4E20.5080503@garzik.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Daniel J Blueman , bzolnier@gmail.com, linux-ide@vger.kernel.org, Linux Kernel , Alan Cox Jeff Garzik wrote: > Mark Lord wrote: >> Some cards may perform better when their "memory" interface is used >> instead of the "I/O" interface, or vice-versa. I'm not sure which >> of the two methods was selected by libata (probably the "memory" >> interface). > > I am very CF-ignorant. How does libata select a memory or I/O interface > on a CF device? Right. Usually we cannot select them, as it's the wires between the ATA chipset (motherboard) and the CFCARD that determine this. So I suppose this means that most implementations are using the I/O access method, except for some embedded systems where the CFCARD is wired to the host bus without a separate "controller" chip in between. Cheers