From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-10.8 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id DF6747D8BA for ; Tue, 8 Jan 2019 16:28:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729457AbfAHQ1F (ORCPT ); Tue, 8 Jan 2019 11:27:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:36170 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728238AbfAHQ1F (ORCPT ); Tue, 8 Jan 2019 11:27:05 -0500 Received: from localhost.localdomain (unknown [218.0.237.216]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A4BC92171F; Tue, 8 Jan 2019 16:26:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1546964824; bh=GnBTm+DeAfY68Ta9VlAGebfCzp0Ny1jRJ1P4AuotXPA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=djCln0PCaBSjTR1zoj/eW6jWwlQ03soI02jRdbtCtrjnhGM6BEYpxJ76d+SDzXtwN ESlNlW+CdbKCOTLNAXJMuz0b2C2yXtve5BTy1Fv4hsBOn7KQDSgRhGFVyVpCuZf53T h6BmQ2yU+KUBB/JKvlptZJHQEA2XrfJJ13ry/yLI= From: guoren@kernel.org To: tglx@linutronix.de, marc.zyngier@arm.com, arnd@arndb.de Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, mhocko@kernel.org, torvalds@linux-foundation.org, linux@roeck-us.net, Guo Ren , Lu Baoquan Subject: [PATCH 3/5] csky: fixup CACHEV1 store instruction fast retire Date: Wed, 9 Jan 2019 00:26:36 +0800 Message-Id: <1546964798-30067-3-git-send-email-guoren@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1546964798-30067-1-git-send-email-guoren@kernel.org> References: <1546964798-30067-1-git-send-email-guoren@kernel.org> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org From: Guo Ren For I/O access, 810/807 store instruction fast retire will cause wrong primitive. For example: stw (clear interrupt source) stw (unmask interrupt controller) enable interrupt stw is fast retire instruction. When PC is run at enable interrupt stage, the clear interrupt source hasn't finished. It will cause another wrong irq-enter. So use mb() to prevent above. Signed-off-by: Guo Ren Cc: Lu Baoquan --- arch/csky/include/asm/io.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/arch/csky/include/asm/io.h b/arch/csky/include/asm/io.h index ecae6b3..c1dfa9c 100644 --- a/arch/csky/include/asm/io.h +++ b/arch/csky/include/asm/io.h @@ -15,6 +15,31 @@ extern void iounmap(void *addr); extern int remap_area_pages(unsigned long address, phys_addr_t phys_addr, size_t size, unsigned long flags); +/* + * I/O memory access primitives. Reads are ordered relative to any + * following Normal memory access. Writes are ordered relative to any prior + * Normal memory access. + * + * For CACHEV1 (807, 810), store instruction could fast retire, so we need + * another mb() to prevent st fast retire. + * + * For CACHEV2 (860), store instruction with PAGE_ATTR_NO_BUFFERABLE won't + * fast retire. + */ +#define readb(c) ({ u8 __v = readb_relaxed(c); rmb(); __v; }) +#define readw(c) ({ u16 __v = readw_relaxed(c); rmb(); __v; }) +#define readl(c) ({ u32 __v = readl_relaxed(c); rmb(); __v; }) + +#ifdef CONFIG_CPU_HAS_CACHEV2 +#define writeb(v,c) ({ wmb(); writeb_relaxed((v),(c)); }) +#define writew(v,c) ({ wmb(); writew_relaxed((v),(c)); }) +#define writel(v,c) ({ wmb(); writel_relaxed((v),(c)); }) +#else +#define writeb(v,c) ({ wmb(); writeb_relaxed((v),(c)); mb(); }) +#define writew(v,c) ({ wmb(); writew_relaxed((v),(c)); mb(); }) +#define writel(v,c) ({ wmb(); writel_relaxed((v),(c)); mb(); }) +#endif + #define ioremap_nocache(phy, sz) ioremap(phy, sz) #define ioremap_wc ioremap_nocache #define ioremap_wt ioremap_nocache -- 2.7.4