From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757028AbYBKShB (ORCPT ); Mon, 11 Feb 2008 13:37:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750901AbYBKSgx (ORCPT ); Mon, 11 Feb 2008 13:36:53 -0500 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:50882 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbYBKSgv (ORCPT ); Mon, 11 Feb 2008 13:36:51 -0500 Date: Mon, 11 Feb 2008 18:36:15 +0000 From: Russell King To: Bartlomiej Zolnierkiewicz Cc: Sergei Shtylyov , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 7/8] ide: add struct ide_port_info instances to legacy host drivers Message-ID: <20080211183615.GA29891@flint.arm.linux.org.uk> References: <20080106170220.6861.4814.sendpatchset@localhost.localdomain> <20080106170310.6861.14522.sendpatchset@localhost.localdomain> <479E3AEA.5090600@ru.mvista.com> <200802020035.30918.bzolnier@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200802020035.30918.bzolnier@gmail.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 02, 2008 at 12:35:30AM +0100, Bartlomiej Zolnierkiewicz wrote: > > > Index: b/drivers/ide/arm/icside.c > > > =================================================================== > > > --- a/drivers/ide/arm/icside.c > > > +++ b/drivers/ide/arm/icside.c > > > @@ -459,11 +456,19 @@ icside_register_v5(struct icside_state * > > > > > > idx[0] = hwif->index; > > > > > > - ide_device_add(idx); > > > + ide_device_add(idx, NULL); > > > > > > return 0; > > > } > > > > > > +static const struct ide_port_info icside_v6_port_info __initdata = { > > > + .host_flags = IDE_HFLAG_SERIALIZE | > > > + IDE_HFLAG_NO_DMA | /* no SFF-style DMA */ > > > + IDE_HFLAG_NO_AUTOTUNE, > > > + .mwdma_mask = ATA_MWDMA2, > > > + .swdma_mask = ATA_SWDMA2, > > > +}; > > > + > > > > Interesting... this driver's support for SWDMA0 is broken since the cycle > > should be 960 ns long, not 480, and SWDMA2 is underclocked using the same > > cycle as SWDMA1, 480 ns... > > Added Russell to Cc:. Underclocking the DMA is not a problem - if you look at the timing diagrams and associated tables in the ATA specifications, you'll find that they specify the *minimum* cycle timings. However, you're correct that SWDMA0 is not able to be supported. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: