From mboxrd@z Thu Jan 1 00:00:00 1970 From: Segher Boessenkool Subject: Re: [PATCH] Remove powerpc specific parts of 3c509 driver Date: Wed, 20 Sep 2006 02:58:39 +0200 Message-ID: <9F6F4A8E-C780-4358-97AA-570B33C0598F@kernel.crashing.org> References: <20060919145433.8fc7d478.sfr@canb.auug.org.au> <20060919184243.GL29167@austin.ibm.com> <45103C62.4080003@genesi-usa.com> <1158708269.6002.186.camel@localhost.localdomain> <488875E7-CCBC-47E1-A273-A2D037A997B2@kernel.crashing.org> <1158711935.6002.226.camel@localhost.localdomain> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Content-Transfer-Encoding: 7bit Cc: Matt Sealey , akpm@osdl.org, Stephen Rothwell , jgarzik@pobox.com, ppc-dev , netdev@vger.kernel.org Return-path: Received: from mail-in-07.arcor-online.net ([151.189.21.47]:2469 "EHLO mail-in-01.arcor-online.net") by vger.kernel.org with ESMTP id S1750784AbWITA7L (ORCPT ); Tue, 19 Sep 2006 20:59:11 -0400 In-Reply-To: <1158711935.6002.226.camel@localhost.localdomain> To: Benjamin Herrenschmidt Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org >> Sure, PCI busses are little-endian. But is readX()/writeX() for PCI >> only? I sure hope not. > > It's defined for PCI and possibly ISA memory. You can use it for other > things if you whish to, but "other things" are arch specific in any > case. Huh? You're saying that only PCI and ISA are standardised busses? >> It would make a lot more sense if readX()/writeX() used the >> endianness >> of the bus they are performed on. > > No way ! Again, it's evil if such a simple thing start doing different > things depending on random external factors. That's your opinion, yes. I'm saying it's *not* doing different things: in both cases it just does the correct-endian access. Also it doesn't depend on "random external factors" -- they're not random factors, and not external either: it only depends on the bus the access is done on. > Different bus -> different accessor. Then please rename readX()/writeX() to pci_readX()/pci_writeX(). >> Now you can say, use readl_be() or something similar, but that's a) >> ugly, >> b) error-prone, c) exponential interface explosion, d) ugly. > > I'd rather has an interface explosion than having black endian magic > happening inside of the accessors. Any comments on a), b) and d) as well? Segher