From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: Re: IDE _GTM/_STM support Date: Mon, 23 May 2005 12:08:05 +0100 Message-ID: <1116846484.5743.34.camel@localhost.localdomain> References: <1116801324.29662.50.camel@tyrosine> <1116802237.5730.29.camel@localhost.localdomain> <1116814023.3852.6.camel@linux-hp.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1116814023.3852.6.camel-ECwVeV2eNyQD0+JXs3kMbRL4W9x8LtSr@public.gmane.org> Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Shaohua Li Cc: Matthew Garrett , acpi-dev List-Id: linux-acpi@vger.kernel.org On Llu, 2005-05-23 at 03:07, Shaohua Li wrote: > > Its waiting for the I/O to finish. The IDE layer needs the request > > queues to be running so you probably need to defer the taskfile calls. > The ACPI spec the _GTF task should be invoked very early. Eg. before > other commands. Deferring the taskfile call possibly can't meet the > requirement, can it? Sorry, I don't understand Linux IDE. The generic > ide resume routine invokes a 'PM_RESUME' request, could _GTF commands be > invoked before the PM_RESUME request? Linux IDE is entirely request queue driven (almost anyway). If you wanted to run a taskfile early you'd really need to go around the IDE layer and perform the task file operations directly. For almost all of the controllers that should not be a big problem as the register addresses, operations and related information are in the IDE hwif structure and issuing a polled taskfile is relatively trivial and standardised code. ie you can go ACPI -> PCI device PCI device -> IDE hwif IDE hwif -> register addresses, ops Directly issue polled taskfile Poll for completion and you can do that even before interrupts are enabled. In the SATA world it gets more complicated but Jeff Garzik's SATA layer seems to have the right functions exposed to issue taskfiles directly. ------------------------------------------------------- This SF.Net email is sponsored by Oracle Space Sweepstakes Want to be the first software developer in space? Enter now for the Oracle Space Sweepstakes! http://ads.osdn.com/?ad_id=7412&alloc_id=16344&op=click