From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933538AbcCIRVl (ORCPT ); Wed, 9 Mar 2016 12:21:41 -0500 Received: from smtprelay2.synopsys.com ([198.182.60.111]:53421 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933264AbcCIRVb (ORCPT ); Wed, 9 Mar 2016 12:21:31 -0500 From: Lada Trimasova To: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Lada Trimasova , Alexey Brodkin , Vineet Gupta Subject: [PATCH] arc: use little endian accesses Date: Wed, 9 Mar 2016 20:21:04 +0300 Message-Id: <1457544064-16167-1-git-send-email-ltrimas@synopsys.com> X-Mailer: git-send-email 2.5.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Memory access primitives should use cpu_to_le16, cpu_to_le32, le16_to_cpu and le32_to_cpu because it is not really guaranteed that drivers handles any ordering themselves. For example, serial port driver doesn't work when kernel is build for arc big endian architecture. Signed-off-by: Lada Trimasova Cc: Alexey Brodkin Cc: Vineet Gupta --- arch/arc/include/asm/io.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/arch/arc/include/asm/io.h b/arch/arc/include/asm/io.h index 694ece8..0b3d5ea 100644 --- a/arch/arc/include/asm/io.h +++ b/arch/arc/include/asm/io.h @@ -129,15 +129,17 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr) #define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); }) /* - * Relaxed API for drivers which can handle any ordering themselves + * This are defined to perform little endian accesses */ #define readb_relaxed(c) __raw_readb(c) -#define readw_relaxed(c) __raw_readw(c) -#define readl_relaxed(c) __raw_readl(c) +#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \ + __raw_readw(c)); __r; }) +#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \ + __raw_readl(c)); __r; }) #define writeb_relaxed(v,c) __raw_writeb(v,c) -#define writew_relaxed(v,c) __raw_writew(v,c) -#define writel_relaxed(v,c) __raw_writel(v,c) +#define writew_relaxed(v,c) __raw_writew((__force u16) cpu_to_le16(v),c) +#define writel_relaxed(v,c) __raw_writel((__force u32) cpu_to_le32(v),c) #include -- 2.5.0