Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755267AbYAWQqR (ORCPT ); Wed, 23 Jan 2008 11:46:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753825AbYAWQqF (ORCPT ); Wed, 23 Jan 2008 11:46:05 -0500 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:41918 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751023AbYAWQqE (ORCPT ); Wed, 23 Jan 2008 11:46:04 -0500 Date: Wed, 23 Jan 2008 16:41:50 +0000 From: Alan Cox To: Haavard Skinnemoen Cc: Marc Pignat , Andrew Victor , kernel@avr32linux.org, linux-kernel@vger.kernel.org, Remy Bohmer , Chip Coldwell Subject: Re: [PATCH 6/6] atmel_serial: Add DMA support Message-ID: <20080123164150.4b162826@lxorguk.ukuu.org.uk> In-Reply-To: <20080123161425.203a0159@dhcp-252-066.norway.atmel.com> References: <1201013444-30370-1-git-send-email-hskinnemoen@atmel.com> <200801231418.38997.marc.pignat@hevs.ch> <20080123143503.764bc8cf@dhcp-252-066.norway.atmel.com> <200801231452.55388.marc.pignat@hevs.ch> <20080123150511.3785986c@dhcp-252-066.norway.atmel.com> <20080123150436.75fe469c@lxorguk.ukuu.org.uk> <20080123161425.203a0159@dhcp-252-066.norway.atmel.com> X-Mailer: Claws Mail 3.2.0 (GTK+ 2.12.3; x86_64-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 890 Lines: 24 On Wed, 23 Jan 2008 16:14:25 +0100 Haavard Skinnemoen wrote: > On Wed, 23 Jan 2008 15:04:36 +0000 > Alan Cox wrote: > > > > No, I think GFP_DMA is for legacy ISA DMA and other DMA controllers > > > with addressing limitations. The PDC is capable of accessing the full > > > 32-bit physical address space on both AT91 and AVR32, so no special DMA > > > flags are needed. > > > > For kernel coherent DMA buffers use the dma_ API to allocate the memory. > > Yes, but since we're managing DMA coherency using the streaming DMA > API, we don't really need coherent buffers, right? Right. Alan -- 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/