Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 9 Jun 2002 02:46:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 9 Jun 2002 02:46:05 -0400 Received: from fachschaft.cup.uni-muenchen.de ([141.84.250.61]:7431 "EHLO fachschaft.cup.uni-muenchen.de") by vger.kernel.org with ESMTP id ; Sun, 9 Jun 2002 02:46:05 -0400 Message-Id: <200206090640.g596e6X14829@fachschaft.cup.uni-muenchen.de> Content-Type: text/plain; charset=US-ASCII From: Oliver Neukum To: "David S. Miller" , roland@topspin.com Subject: Re: PCI DMA to small buffers on cache-incoherent arch Date: Sun, 9 Jun 2002 08:45:49 +0200 X-Mailer: KMail [version 1.3.1] Cc: linux-kernel@vger.kernel.org In-Reply-To: <52lm9p9tdz.fsf@topspin.com> <52d6v19r9n.fsf@topspin.com> <20020608.222903.122223122.davem@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Sonntag, 9. Juni 2002 07:29 schrieb David S. Miller: > From: Roland Dreier > Date: 08 Jun 2002 18:26:12 -0700 > > Just to make sure I'm reading this correctly, you're saying that as > long as a buffer is OK for DMA, it should be OK to use a > sub-cache-line chunk as a DMA buffer via pci_map_single(), and > accessing the rest of the cache line should be OK at any time before, > during and after the DMA. > > Yes. Does this mean that this piece of memory does have to be declared uncacheable until DMA is finished ? How else do you solve th problem of validity during DMA and especially after DMA ? Regards Oliver - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/