From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH] libata: Add MMIO support to pata_sil680 Date: Thu, 24 May 2007 20:08:50 +1000 Message-ID: <1180001330.32247.1058.camel@localhost.localdomain> References: <20070515061239.611A2DDEE9@ozlabs.org> <1179209697.32247.153.camel@localhost.localdomain> <20070523144217.5abd9fdf@the-village.bc.nu> <1179960518.32247.948.camel@localhost.localdomain> <20070524003123.77b9c81c@the-village.bc.nu> <46552A63.4080002@pobox.com> <20070524093316.GB10777@devserv.devel.redhat.com> <4655611E.6050805@garzik.org> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from gate.crashing.org ([63.228.1.57]:45285 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754665AbXEXKJD (ORCPT ); Thu, 24 May 2007 06:09:03 -0400 In-Reply-To: <4655611E.6050805@garzik.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Alan Cox , Alan Cox , Linux IDE On Thu, 2007-05-24 at 05:55 -0400, Jeff Garzik wrote: > Alan Cox wrote: > > On Thu, May 24, 2007 at 02:02:11AM -0400, Jeff Garzik wrote: > >> Ben's patch got merged because it does not change the status quo. This > > > > Yes it does - Thats PATA and now > > PATA + MMIO so the problem case. > > hmmm, true. I think Jeff is right. I was not completley sure about the 400ns case in ata_pause but I think it's a good idea to use mmio_flush hook there. The only thing that I'm wondering about a bit is that ata_pause so far uses read of altstatus which _is_ a taskfile register. It's my understanding that we should avoid doing so in that case. So my patch will use the new mmio_flush hook instead, however, that means that PIO and SATA controllers will have NULL there, thus no read. We will have to be careful just in case something actually manages to regress because of the loss of that read. (with IDE, anything is possible !) Cheers, Ben.