From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: MMIO and gcc re-ordering issue Date: Fri, 30 May 2008 11:13:23 +1000 Message-ID: <1212110003.15633.0.camel@pasglop> References: <1211852026.3286.36.camel@pasglop> <20080526.184047.88207142.davem@davemloft.net> <1211854540.3286.42.camel@pasglop> <20080526.192812.184590464.davem@davemloft.net> <1211859542.3286.46.camel@pasglop> <1211922621.3286.80.camel@pasglop> <1211924335.3286.89.camel@pasglop> <20080527214241.GA22636@parisc-linux.org> <1211926636.3286.100.camel@pasglop> <20080528103648.54eb8734@hskinnemo-gx745.norway.atmel.com> Reply-To: benh@kernel.crashing.org Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from gate.crashing.org ([63.228.1.57]:49071 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752728AbYE3BN6 (ORCPT ); Thu, 29 May 2008 21:13:58 -0400 In-Reply-To: <20080528103648.54eb8734@hskinnemo-gx745.norway.atmel.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Haavard Skinnemoen Cc: Matthew Wilcox , Linus Torvalds , David Miller , linux-arch@vger.kernel.org, scottwood@freescale.com, linuxppc-dev@ozlabs.org, alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org, tpiepho@freescale.com > I do -- in all the drivers for on-chip peripherals that are shared > between AT91 ARM (LE) and AVR32 (BE). Since everything goes on inside > the chip, we must use LE accesses on ARM and BE accesses on AVR32. > > Currently, this is the only interface I know that can do native-endian > accesses, so if you take it away, I'm gonna need an alternative > interface that doesn't do byteswapping. Are you aware that these also don't provide any ordering guarantee ? Ben.