From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailhub1.si.c-s.fr (pegase1.c-s.fr [93.17.236.30]) by lists.ozlabs.org (Postfix) with ESMTP id 8836A1A0D13 for ; Tue, 3 Feb 2015 22:39:35 +1100 (AEDT) From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras , scottwood@freescale.com Subject: [PATCH v2 2/2] powerpc32: add support for csum_add() Message-Id: <20150203113927.8604D1A5F14@localhost.localdomain> Date: Tue, 3 Feb 2015 12:39:27 +0100 (CET) Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The C version of csum_add() as defined in include/net/checksum.h gives the following assembly: 0: 7c 04 1a 14 add r0,r4,r3 4: 7c 64 00 10 subfc r3,r4,r0 8: 7c 63 19 10 subfe r3,r3,r3 c: 7c 63 00 50 subf r3,r3,r0 include/net/checksum.h also offers the possibility to define an arch specific function. This patch provides a ppc32 specific csum_add() inline function. Signed-off-by: Christophe Leroy --- v2: changed constraints on the __asm__ arch/powerpc/include/asm/checksum.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index cfe806a..1e48cc7 100644 --- a/arch/powerpc/include/asm/checksum.h +++ b/arch/powerpc/include/asm/checksum.h @@ -141,6 +141,18 @@ static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, { return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); } + +#define HAVE_ARCH_CSUM_ADD +static inline __wsum csum_add(__wsum csum, __wsum addend) +{ + __asm__("\n\ + addc %0,%0,%1 \n\ + addze %0,%0 \n\ + " + : "+r" (csum) : "r" (addend)); + return csum; +} + #endif #endif #endif /* __KERNEL__ */ -- 2.1.0