From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760351AbXFIT55 (ORCPT ); Sat, 9 Jun 2007 15:57:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758904AbXFIT5q (ORCPT ); Sat, 9 Jun 2007 15:57:46 -0400 Received: from ug-out-1314.google.com ([66.249.92.168]:56696 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758800AbXFIT5p convert rfc822-to-8bit (ORCPT ); Sat, 9 Jun 2007 15:57:45 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:from:to:subject:date:user-agent:cc:references:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:message-id; b=aM9oh8WRHDCVn/yd9qU23vYJNQWKIuiSrcBp5viqLAS6uQg/S37q/TofrTaUyK6ngL7Mgj2E1vSIeulVlVqtZEFIDJCSI/bZmloO8IbIivHyPIx/rGkSA5j/+GRUvU4sn3ZsIyqQwQczx8OdWJG+AqASy5m0d3o7Q6XIz4KnbF8= From: Bartlomiej Zolnierkiewicz To: Tejun Heo Subject: Re: [PATCH] pata_it821x: sync with IDE it821x driver Date: Sat, 9 Jun 2007 22:09:10 +0200 User-Agent: KMail/1.9.6 Cc: Jeff Garzik , Alan Cox , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org References: <200706090223.20933.bzolnier@gmail.com> <466A417C.5090901@gmail.com> In-Reply-To: <466A417C.5090901@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 8BIT Content-Disposition: inline Message-Id: <200706092209.10636.bzolnier@gmail.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Saturday 09 June 2007, Tejun Heo wrote: > Hello, > > Bartlomiej Zolnierkiewicz wrote: > > * (partially) fix DMA in RAID mode > > > > Code intended to check DMA status was checking DMA command register. > > Moreover firmware seems to "forget" to set DMA capable bit for the > > slave device (at least in RAID mode but without ITE RAID volumes) so > > check device ID for DMA capable bit when deciding whether to use DMA > > and remove DMA status check completely. > > > > Thanks to Pavol Šimo for the bugreport and testing the initial fix. > > Ah... This is the mysterious mwdma configuration in smart mode, right? Yep. > Thanks for fixing this. > > > This change unfortunately still doesn't fix DMA in RAID mode (which > > works fine with IDE it821x) but Alan is working on the missing pieces > > (pata_it821x vs libata EH issues). > > This is the lbal/nsect SRST problem, right? I think so, due to lack of time I'm not following libata discussions closely. > > @@ -258,8 +259,14 @@ static void it821x_passthru_set_piomode( > > static const u8 pio_want[] = { ATA_66, ATA_66, ATA_66, ATA_66, ATA_ANY }; > > > > struct it821x_dev *itdev = ap->private_data; > > + struct ata_device *pair = ata_dev_pair(adev); > > int unit = adev->devno; > > - int mode_wanted = adev->pio_mode - XFER_PIO_0; > > + int mode_wanted = adev->pio_mode; > > + > > + if (pair && adev->pio_mode > pair->pio_mode) > > + mode_wanted = pair->pio_mode; > > + > > + mode_wanted -= XFER_PIO_0; > > I think this is better done by mode_filter callback which is guaranteed > to be called before any actual mode configuration is performed and in > device order (master then slave). I was thinking about using ->mode_filter but since all other PATA host drivers are doing PIO filtering in ->set_piomode methods and also since it seemed that using ->mode_filter method would result in slightly more complex code I opted for coherency / simplicity. However if you (or somebody else) want to make a follow-up change to this driver (and preferably other PATA host drivers ie. pata_sil680) to use ->mode_filter I'm also fine with that. Thanks, Bart