From patchwork Tue Apr 17 04:08:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sinan Kaya X-Patchwork-Id: 10344299 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DCA5260365 for ; Tue, 17 Apr 2018 04:09:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CD2CD2896A for ; Tue, 17 Apr 2018 04:09:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C162B28929; Tue, 17 Apr 2018 04:09:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3F5ED28929 for ; Tue, 17 Apr 2018 04:09:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751970AbeDQEJF (ORCPT ); Tue, 17 Apr 2018 00:09:05 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:47704 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752261AbeDQEJD (ORCPT ); Tue, 17 Apr 2018 00:09:03 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 3A55B602B8; Tue, 17 Apr 2018 04:09:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1523938143; bh=sCQGuLK4L3UgFxvytfuLMoihb5z5GU54TY5P9NCpoXo=; h=From:To:Cc:Subject:Date:From; b=PWKPpMypUKv0ilodm7WgKlvjYiFry5eBMDlK8pR8jJCuwUx/abL3QTMNB/EcjjK7y j0KpRfXMlB7ABmnEuc6yzcPfvRmTB0z0kWpIqndPkiVbTSdR3hwkddtRwcXXMDlgEz /OeCcHL8kFzqOuZ2GJrgh3/r9fWVhRKHCtulNySU= Received: from drakthul.qualcomm.com (global_nat1_iad_fw.qualcomm.com [129.46.232.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: okaya@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id E50EA602B8; Tue, 17 Apr 2018 04:09:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1523938142; bh=sCQGuLK4L3UgFxvytfuLMoihb5z5GU54TY5P9NCpoXo=; h=From:To:Cc:Subject:Date:From; b=ZPM4Yw+YDxIdh4viz3R0qBUOYxCzSUL44xQGYioBtbJ7JCUjUvmP9UwGOZxs4+lbb R0jtqqPppyduo5MfPgF6nA0CpAflJ2pTCS/mwtBHQsvUF6KKtH+Nf0yc37pabwRbY+ c5tvR3vM9ZqA/GnCwewNh5/ZHX0g8kw0jB3LA3iQ= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org E50EA602B8 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=okaya@codeaurora.org From: Sinan Kaya To: linux-parisc@vger.kernel.org, arnd@arndb.de, timur@codeaurora.org, sulrich@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya , "James E.J. Bottomley" , Helge Deller , Thomas Gleixner , Greg Kroah-Hartman , Philippe Ombredanne , linux-kernel@vger.kernel.org Subject: [PATCH v2 1/2] parisc: define stronger ordering for the default writeX() Date: Tue, 17 Apr 2018 00:08:50 -0400 Message-Id: <1523938133-3224-1-git-send-email-okaya@codeaurora.org> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP parisc architecture seems to be mapping writeX() and writeX_relaxed() APIs to __raw_writeX() API. __raw_writeX() API doesn't provide any kind of ordering guarantees. commit 755bd04aaf4b ("io: define stronger ordering for the default writeX() implementation") changed asm-generic implementation to use a more conservative approach towards the writeX() API. Place a barrier() before the register write so that compiler doesn't optimize across the regiter operation. Signed-off-by: Sinan Kaya --- arch/parisc/include/asm/io.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h index afe493b..2ec6405 100644 --- a/arch/parisc/include/asm/io.h +++ b/arch/parisc/include/asm/io.h @@ -196,18 +196,22 @@ static inline unsigned long long readq(const volatile void __iomem *addr) static inline void writeb(unsigned char b, volatile void __iomem *addr) { + barrier(); __raw_writeb(b, addr); } static inline void writew(unsigned short w, volatile void __iomem *addr) { + barrier(); __raw_writew((__u16 __force) cpu_to_le16(w), addr); } static inline void writel(unsigned int l, volatile void __iomem *addr) { + barrier(); __raw_writel((__u32 __force) cpu_to_le32(l), addr); } static inline void writeq(unsigned long long q, volatile void __iomem *addr) { + barrier(); __raw_writeq((__u64 __force) cpu_to_le64(q), addr); }