From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: [PATCH 1/2] asm-generic/io: Pass result on inX() accessor to __io_par() Date: Mon, 11 Feb 2019 17:45:43 +0000 Message-ID: <20190211174544.4302-2-will.deacon@arm.com> References: <20190211174544.4302-1-will.deacon@arm.com> Return-path: In-Reply-To: <20190211174544.4302-1-will.deacon@arm.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org, andrew.murray@arm.com, arnd@arndb.de, catalin.marinas@arm.com, Will Deacon List-Id: linux-arch.vger.kernel.org The inX() I/O accessors must enforce ordering against subsequent calls to the delay() routines, so that a read-back from a device can be used to postpone a subsequent write to the same device. On some architectures, including arm64, this ordering can only be achieved by creating a dependency on the value returned by the inX() operation, so we need to pass the value we read to the __io_par() macro in this case. Reported-by: Andrew Murray Signed-off-by: Will Deacon --- include/asm-generic/io.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index d356f802945a..b5737c0d8316 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -65,7 +65,7 @@ #endif #ifndef __io_par -#define __io_par() __io_ar() +#define __io_par(v) __io_ar() #endif @@ -471,7 +471,7 @@ static inline u8 inb(unsigned long addr) __io_pbr(); val = __raw_readb(PCI_IOBASE + addr); - __io_par(); + __io_par(val); return val; } #endif @@ -484,7 +484,7 @@ static inline u16 inw(unsigned long addr) __io_pbr(); val = __le16_to_cpu(__raw_readw(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif @@ -497,7 +497,7 @@ static inline u32 inl(unsigned long addr) __io_pbr(); val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif -- 2.11.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.101.70]:54876 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730177AbfBKRpw (ORCPT ); Mon, 11 Feb 2019 12:45:52 -0500 From: Will Deacon Subject: [PATCH 1/2] asm-generic/io: Pass result on inX() accessor to __io_par() Date: Mon, 11 Feb 2019 17:45:43 +0000 Message-ID: <20190211174544.4302-2-will.deacon@arm.com> In-Reply-To: <20190211174544.4302-1-will.deacon@arm.com> References: <20190211174544.4302-1-will.deacon@arm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org, andrew.murray@arm.com, arnd@arndb.de, catalin.marinas@arm.com, Will Deacon Message-ID: <20190211174543.1GeOGQvBXRNZDnZQ1n87W7fQRpDe4Un4vk_pfL5tMc0@z> The inX() I/O accessors must enforce ordering against subsequent calls to the delay() routines, so that a read-back from a device can be used to postpone a subsequent write to the same device. On some architectures, including arm64, this ordering can only be achieved by creating a dependency on the value returned by the inX() operation, so we need to pass the value we read to the __io_par() macro in this case. Reported-by: Andrew Murray Signed-off-by: Will Deacon --- include/asm-generic/io.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index d356f802945a..b5737c0d8316 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -65,7 +65,7 @@ #endif #ifndef __io_par -#define __io_par() __io_ar() +#define __io_par(v) __io_ar() #endif @@ -471,7 +471,7 @@ static inline u8 inb(unsigned long addr) __io_pbr(); val = __raw_readb(PCI_IOBASE + addr); - __io_par(); + __io_par(val); return val; } #endif @@ -484,7 +484,7 @@ static inline u16 inw(unsigned long addr) __io_pbr(); val = __le16_to_cpu(__raw_readw(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif @@ -497,7 +497,7 @@ static inline u32 inl(unsigned long addr) __io_pbr(); val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); - __io_par(); + __io_par(val); return val; } #endif -- 2.11.0