Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759590AbaJaFmx (ORCPT ); Fri, 31 Oct 2014 01:42:53 -0400 Received: from cnbjrel02.sonyericsson.com ([219.141.167.166]:5810 "EHLO cnbjrel02.sonyericsson.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753058AbaJaFmw convert rfc822-to-8bit (ORCPT ); Fri, 31 Oct 2014 01:42:52 -0400 From: "Wang, Yalin" To: "'Will Deacon'" , "'Ard Biesheuvel'" CC: "'Russell King - ARM Linux'" , "'linux-kernel@vger.kernel.org'" , "'akinobu.mita@gmail.com'" , "'linux-mm@kvack.org'" , "'Joe Perches'" , "'linux-arm-kernel@lists.infradead.org'" Date: Fri, 31 Oct 2014 13:42:44 +0800 Subject: [RFC V6 2/3] arm:add bitrev.h file to support rbit instruction Thread-Topic: [RFC V6 2/3] arm:add bitrev.h file to support rbit instruction Thread-Index: Ac/0SYsLYyTdMNPAS1SmHcF7f8oZ+gAcg3/QAARlW3AAAA1OUA== Message-ID: <35FD53F367049845BC99AC72306C23D103E010D18275@CNBJMBX05.corpusers.net> References: <1414392371.8884.2.camel@perches.com> <35FD53F367049845BC99AC72306C23D103E010D1825F@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18260@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18261@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18264@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18265@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18266@CNBJMBX05.corpusers.net> <20141030120127.GC32589@arm.com> <20141030135749.GE32589@arm.com> <35FD53F367049845BC99AC72306C23D103E010D18272@CNBJMBX05.corpusers.net> <35FD53F367049845BC99AC72306C23D103E010D18273@CNBJMBX05.corpusers.net> In-Reply-To: <35FD53F367049845BC99AC72306C23D103E010D18273@CNBJMBX05.corpusers.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch add bitrev.h file to support rbit instruction, so that we can do bitrev operation by hardware. Signed-off-by: Yalin Wang --- arch/arm/Kconfig | 1 + arch/arm/include/asm/bitrev.h | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) create mode 100644 arch/arm/include/asm/bitrev.h diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 89c4b5c..be92b3b 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -28,6 +28,7 @@ config ARM select HANDLE_DOMAIN_IRQ select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) + select HAVE_ARCH_BITREVERSE if (CPU_V7M || CPU_V7) select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h new file mode 100644 index 0000000..e9b2571 --- /dev/null +++ b/arch/arm/include/asm/bitrev.h @@ -0,0 +1,21 @@ +#ifndef __ASM_ARM_BITREV_H +#define __ASM_ARM_BITREV_H + +static __always_inline __attribute_const__ u32 __arch_bitrev32(u32 x) +{ + __asm__ ("rbit %0, %1" : "=r" (x) : "r" (x)); + return x; +} + +static __always_inline __attribute_const__ u16 __arch_bitrev16(u16 x) +{ + return __arch_bitrev32((u32)x) >> 16; +} + +static __always_inline __attribute_const__ u8 __arch_bitrev8(u8 x) +{ + return __arch_bitrev32((u32)x) >> 24; +} + +#endif + -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/