From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Subject: Re: [parisc-linux] readb/__raw_readb/gsc_readb and ioremap Date: Sat, 30 Oct 2004 22:37:16 -0600 Message-ID: <20041031043716.GD5050@colo.lackof.org> References: <20041031033950.GN8958@parcelfarce.linux.theplanet.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: parisc-linux@parisc-linux.org To: Matthew Wilcox Return-Path: In-Reply-To: <20041031033950.GN8958@parcelfarce.linux.theplanet.co.uk> List-Id: parisc-linux developers list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: parisc-linux-bounces@lists.parisc-linux.org On Sun, Oct 31, 2004 at 03:39:50AM +0000, Matthew Wilcox wrote: > __raw_read/writeX: > - Don't byteswap > - Should be used on ioremap'ed address > read/writeX: > - Byteswap > - Should be used on ioremap'ed address Willy confirmed there is another subtle difference between the two sets of functions: __raw_read/writeX relax PCI ordering requirements. read/writeX enforce PCI Ordering requirements. Willy correctly ignored this topic since parisc machines are strongly ordered for IO as well (so far at least). But I didn't want folks to think byte swapping was the only difference. Be VERY careful of using __raw_XXX forms outside of parisc specific code. grant _______________________________________________ parisc-linux mailing list parisc-linux@lists.parisc-linux.org http://lists.parisc-linux.org/mailman/listinfo/parisc-linux