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Date: Fri, 29 Aug 2014 11:14:38 +0200 (CEST) From: Christophe Leroy <christophe.leroy@....fr> To: Benjamin Herrenschmidt <benh@...nel.crashing.org>, Paul Mackerras <paulus@...ba.org> CC: linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org, Joakim Tjernlund <joakim.tjernlund@...nsmode.se>, scottwood@...escale.com Subject: [PATCH v2 09/19] powerpc/8xx: Optimize verification in FixupDAR 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 <christophe.leroy@....fr> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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