From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: ata_std_qc_defer not good enough for FIS-based switching ? Date: Mon, 28 Apr 2008 19:42:21 -0400 Message-ID: <481660DD.80103@rtr.ca> References: <48163C5D.9050605@rtr.ca> <48164AE8.4070106@rtr.ca> <481659B5.7090703@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([76.10.145.34]:2917 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934176AbYD1XmX (ORCPT ); Mon, 28 Apr 2008 19:42:23 -0400 In-Reply-To: <481659B5.7090703@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Jeff Garzik , IDE/ATA development list , Alan Cox Tejun Heo wrote: > Hello, Mark. > > Mark Lord wrote: >>> Are there controllers which *can* handle such a mix (ahci, sil24 ?) > > Yeap, sil24 can. ahci can currently only do device based switching but > ahci 2.0 can do it too. > >>> So it looks like a I need a .qc_defer() function which examines all >>> links >>> from the common host port for activity, and then asks for command >>> deferral >>> when the new command has a different protocol than those that are >>> outstanding. >>> >>> Weird that none of the other LLDs need this. Or do they? > > So, none of the others needs this. .. Mmm.. I just plugged the same PM + drives into my sata_sil24 card here, and that driver went bonkers when I did the same test. Had to reboot eventually to recover. Weird.