From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: new ata_port_operations for .pmp_{read,write} ? Date: Mon, 25 Feb 2008 19:12:21 -0500 Message-ID: <47C35965.7030905@rtr.ca> References: <4730E312.3090900@navy.mil> <4737C16E.3070607@gmail.com> <4738827D.9060405@pobox.com> <4738F935.1000708@gmail.com> <47BC798F.6070900@pobox.com> <47BE17CA.6060406@rtr.ca> <47BE1833.9090501@rtr.ca> <47BE2C0C.3020801@gmail.com> <47BE2DBD.9010704@rtr.ca> <47BE2F9E.5040206@gmail.com> <47BE32B5.5020300@rtr.ca> <47BE3325.8060209@rtr.ca> <47BE4701.2030104@rtr.ca> <47BE4DFE.2030407@rtr.ca> <47BEDAF2.8000301@rtr.ca> <47BFAC06.5030805@rtr.ca> <47C116D4.1090600@gmail.com> <47C248C8.9090409@rtr.ca> <47C2503A.7040308@gmail.com> <47C2F308.1080602@rtr.ca> <47C352E9.4060107@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]:4002 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760076AbYBZAJe (ORCPT ); Mon, 25 Feb 2008 19:09:34 -0500 In-Reply-To: <47C352E9.4060107@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: IDE/ATA development list , Saeed Bishara , Jeff Garzik Tejun Heo wrote: > > libata doesn't really put much restrictions on what a LLD should do on > entering EH and if the controller's behavior is predictable, there's no > reason to freeze the port. If the problem is that the DMA engine isn't > usable after PMP error but it's known that the controller isn't gonna > cause irq storm, no need to freeze. The only command EH issues before > resetting which can use DMA protocol is READ_LOG_EXT. Maybe there needs > to be a way to force PIO protocol for READ_LOG_EXT. Other than that, if > no-data and PIO-only commands work fine, EH autopsy should work fine. .. Eh? READ LOG EXT *is* a PIO command, as opposed to READ LOG DMA EXT which uses DMA. And the EH also issues PIO READ_BUFFER commands for PM ports, if a PM is present. ???