From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] libata: share PIO limits among devices sharing a channel Date: Thu, 25 Jan 2007 22:30:07 +0900 Message-ID: <45B8B0DF.4080602@gmail.com> References: <20070125112947.GC8606@htj.dyndns.org> <20070125123030.3093fb32@localhost.localdomain> <45B8A63F.8060305@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from an-out-0708.google.com ([209.85.132.251]:8297 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965152AbXAYNaQ (ORCPT ); Thu, 25 Jan 2007 08:30:16 -0500 Received: by an-out-0708.google.com with SMTP id b33so331259ana for ; Thu, 25 Jan 2007 05:30:15 -0800 (PST) In-Reply-To: <45B8A63F.8060305@pobox.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Alan , linux-ide@vger.kernel.org Jeff Garzik wrote: > Alan wrote: >> On Thu, 25 Jan 2007 20:29:47 +0900 >> Tejun Heo wrote: >> >>> PIO xfermask limits should be shared by all devices on the same >>> channel to avoid violating device selection timing. libata used to >> >> NAK, this is totally wrong Eek.. You actually said this is/was documented and relied upon all over. http://thread.gmane.org/gmane.linux.ide/13184/focus=14486 (searching mailboxes more...) Oh, and the dropping of common PIO mode selection was agreed upon by Jeff and Alan. One way or the other, this only affects PATA devices and as long as all PATA LLDs guarantee that selection timing isn't violated, this can go. I thought PATA drivers still relied on this common denominator PIO mode configuration. I think it's Alan's call. > I'm curious what the motivation of this patch was? Hope my intentions are explained. Thanks. -- tejun