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 024E81A0B1E for ; Fri, 29 Aug 2014 19:14:44 +1000 (EST) From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras Subject: [PATCH v2 09/19] powerpc/8xx: Optimize verification in FixupDAR Message-Id: <20140829091438.D8D851ABD67@localhost.localdomain> Date: Fri, 29 Aug 2014 11:14:38 +0200 (CEST) Cc: scottwood@freescale.com, 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: , By XORing the upper part of the instruction code, we get a value that can directly be verified with the second test and we can remove the first test. Signed-off-by: Christophe Leroy --- arch/powerpc/kernel/head_8xx.S | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index e5a250c..5037420 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -542,10 +542,8 @@ FixupDAR:/* Entry point for dcbx workaround. */ /* Check if it really is a dcbx instruction. */ /* dcbt and dcbtst does not generate DTLB Misses/Errors, * no need to include them here */ - srwi r10, r11, 26 /* check if major OP code is 31 */ - cmpwi cr0, r10, 31 - bne- 141f - rlwinm r10, r11, 0, 21, 30 + xoris r10, r11, 0x7c00 /* check if major OP code is 31 */ + rlwinm r10, r10, 0, 21, 5 cmpwi cr0, r10, 2028 /* Is dcbz? */ beq+ 142f cmpwi cr0, r10, 940 /* Is dcbi? */ -- 1.7.1