From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29307C48BE4 for ; Sun, 23 Jun 2019 18:25:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0F08620645 for ; Sun, 23 Jun 2019 18:25:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726677AbfFWSZD (ORCPT ); Sun, 23 Jun 2019 14:25:03 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:43474 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726399AbfFWSZD (ORCPT ); Sun, 23 Jun 2019 14:25:03 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id B318A1263F1F8; Sun, 23 Jun 2019 11:25:02 -0700 (PDT) Date: Sun, 23 Jun 2019 11:25:02 -0700 (PDT) Message-Id: <20190623.112502.1981269479319700405.davem@davemloft.net> To: paul.burton@mips.com Cc: macro@linux-mips.org, netdev@vger.kernel.org, pburton@wavecomp.com, Sergey.Semin@t-platforms.ru, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] FDDI: defza: Include linux/io-64-nonatomic-lo-hi.h From: David Miller In-Reply-To: <20190620221224.27352-1-paul.burton@mips.com> References: <20190620221224.27352-1-paul.burton@mips.com> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 23 Jun 2019 11:25:03 -0700 (PDT) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org From: Paul Burton Date: Thu, 20 Jun 2019 22:13:58 +0000 > Currently arch/mips/include/asm/io.h provides 64b memory accessor > functions such as readq & writeq even on MIPS32 platforms where those > accessors cannot actually perform a 64b memory access. They instead > BUG(). This is unfortunate for drivers which either #ifdef on the > presence of these accessors, or can function with non-atomic > implementations of them found in either linux/io-64-nonatomic-lo-hi.h or > linux/io-64-nonatomic-hi-lo.h. As such we're preparing to remove the > definitions of these 64b accessor functions for MIPS32 kernels. > > In preparation for this, include linux/io-64-nonatomic-lo-hi.h in > defza.c in order to provide a non-atomic implementation of the > readq_relaxed & writeq_relaxed functions that are used by this code. In > practice this will have no runtime effect, since use of the 64b accessor > functions is conditional upon sizeof(unsigned long) == 8, ie. upon > CONFIG_64BIT=y. This means the calls to these non-atomic readq & writeq > implementations will be optimized out anyway, but we need their > definitions to keep the compiler happy. > > For 64bit kernels using this code this change should also have no effect > because asm/io.h will continue to provide the definitions of > readq_relaxed & writeq_relaxed, which linux/io-64-nonatomic-lo-hi.h > checks for before defining itself. > > Signed-off-by: Paul Burton ... > Maciej, David, if you'd be happy to provide an Ack so that I can take > this through the mips-next branch that would be great; that'll let me > apply it prior to the asm/io.h change. Acked-by: David S. Miller