From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) by kanga.kvack.org (Postfix) with ESMTP id 3DF91280022 for ; Fri, 31 Oct 2014 01:41:55 -0400 (EDT) Received: by mail-pa0-f49.google.com with SMTP id lj1so6912167pab.8 for ; Thu, 30 Oct 2014 22:41:54 -0700 (PDT) Received: from cnbjrel02.sonyericsson.com (cnbjrel02.sonyericsson.com. [219.141.167.166]) by mx.google.com with ESMTPS id tl10si8464218pac.46.2014.10.30.22.41.53 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 30 Oct 2014 22:41:54 -0700 (PDT) From: "Wang, Yalin" Date: Fri, 31 Oct 2014 13:41:48 +0800 Subject: [RFC V6 3/3] arm64:add bitrev.h file to support rbit instruction Message-ID: <35FD53F367049845BC99AC72306C23D103E010D18274@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> In-Reply-To: <35FD53F367049845BC99AC72306C23D103E010D18272@CNBJMBX05.corpusers.net> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: "Wang, Yalin" , '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'" 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/arm64/Kconfig | 1 + arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) create mode 100644 arch/arm64/include/asm/bitrev.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 9532f8d..b1ec1dd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -35,6 +35,7 @@ config ARM64 select HANDLE_DOMAIN_IRQ select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_BITREVERSE select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB select HAVE_ARCH_TRACEHOOK diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitre= v.h new file mode 100644 index 0000000..706a209 --- /dev/null +++ b/arch/arm64/include/asm/bitrev.h @@ -0,0 +1,21 @@ +#ifndef __ASM_ARM64_BITREV_H +#define __ASM_ARM64_BITREV_H + +static __always_inline __attribute_const__ u32 __arch_bitrev32(u32 x) +{ + __asm__ ("rbit %w0, %w1" : "=3Dr" (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 + --=20 2.1.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org