From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261217AbVG1NCU (ORCPT ); Thu, 28 Jul 2005 09:02:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261232AbVG1NCU (ORCPT ); Thu, 28 Jul 2005 09:02:20 -0400 Received: from coderock.org ([193.77.147.115]:2495 "EHLO trashy.coderock.org") by vger.kernel.org with ESMTP id S261217AbVG1NCT (ORCPT ); Thu, 28 Jul 2005 09:02:19 -0400 Date: Thu, 28 Jul 2005 15:02:19 +0200 From: Domen Puncer To: Paul Mackerras Cc: Andrew Morton , Matt Porter , wfarnsworth@mvista.com, linuxppc-embedded@ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][1/3] ppc32: add 440ep support Message-ID: <20050728130219.GB2249@homer.coderock.org> References: <11224856623638@foobar.com> <20050727131857.78a56972.akpm@osdl.org> <17128.4407.838024.111955@cargo.ozlabs.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <17128.4407.838024.111955@cargo.ozlabs.ibm.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 27/07/05 18:56 -0400, Paul Mackerras wrote: > Andrew Morton writes: > > > Matt Porter wrote: > > > > > > +static u64 dma_mask = 0xffffffffULL; How about just DMA_32BIT_MASK from dma-mapping.h, that one has to be correct. ;-) > > > > I'm sure you're totally uninterested in this, but the above will probably > > generate warnings on (say) ppc64, where u64 is implemented as unsigned > > long. > > > > I usually chuck a simple `-1' in there and the compiler always gets it > > right, regardless of signedness and size and architecture. > > Umm, I think we actually want 2^32-1 not -1, don't we? In which case > I think Matt's code is what we have to have. > > I tried a little test compile with gcc 4.0 with -m64 -Wall and it > didn't generate a warning with the 0xffffffffULL constant.