From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756348AbaHHHEh (ORCPT ); Fri, 8 Aug 2014 03:04:37 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:45272 "EHLO mailhub1.si.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756293AbaHHHEb (ORCPT ); Fri, 8 Aug 2014 03:04:31 -0400 From: Christophe Leroy To: Benjamin Herrenschmidt , Paul Mackerras CC: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Joakim Tjernlund , scottwood@freescale.com Subject: [PATCH 09/20] powerpc/8xx: Optimize verification in FixupDAR Message-Id: <20140808070342.671FB1ABD45@localhost.localdomain> Date: Fri, 8 Aug 2014 09:03:42 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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