From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] libata: implement and use DMA mask configuration helper Date: Sun, 18 Mar 2007 23:48:52 +0900 Message-ID: <45FD5154.9040603@gmail.com> References: <20070309104945.GG32687@htj.dyndns.org> <45F155E3.9040604@garzik.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from py-out-1112.google.com ([64.233.166.182]:25080 "EHLO py-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752789AbXCROs5 (ORCPT ); Sun, 18 Mar 2007 10:48:57 -0400 Received: by py-out-1112.google.com with SMTP id a29so207988pyi for ; Sun, 18 Mar 2007 07:48:57 -0700 (PDT) In-Reply-To: <45F155E3.9040604@garzik.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: linux-ide@vger.kernel.org Jeff Garzik wrote: > Tejun Heo wrote: >> Implement and use DMA mask configuration helper. >> >> Signed-off-by: Tejun Heo >> --- >> This function probably belongs to pci layer. Put it in libata with >> pci_test_bits() for the time being. > > AFAIK the default DMA mask is always 32-bit. Code (often written by me) > that sets it to a 32-bit mask was just paranoia, and not really needed. > > Hence, the pci_go_64() function I added, found in #upstream. It isn't in #upstream yet. Also, at the second thought, there is a problem with pci_go_64(). DMA masks are not reset after driver is detached. Even if the device starts with 32bit DMA masks, after a 64bit enabled driver is attached and detached, the device's DMA masks are 64bit. I'm refreshing new-init-model patchset and keeping pci_configure_dma_masks() for now. Thanks. -- tejun