Patchwork [v2,1/2] powerpc: net: filter: fix DIVWU instruction opcode

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Submitter Vladimir Murzin
Date Sept. 28, 2013, 8:22 a.m.
Message ID <1380356521-3432-1-git-send-email-murzin.v@gmail.com>
Download mbox | patch
Permalink /patch/278721/
State Accepted, archived
Headers show

Comments

Vladimir Murzin - Sept. 28, 2013, 8:22 a.m.
Currently DIVWU stands for *signed* divw opcode:

7d 2a 4b 96 	divwu   r9,r10,r9
7d 2a 4b d6 	divw    r9,r10,r9

Use the *unsigned* divw opcode for DIVWU.

Suggested-by: Vassili Karpov <av1474@comtv.ru>
Reviewed-by: Vassili Karpov <av1474@comtv.ru>
Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Acked-by: Matt Evans <matt@ozlabs.org>
---
Changelog

v1->v2

Added credit to Vassili Karpov (malc) who kindly reviewed generated assembly
[1] and highlighted usage of signed division.
Note: temporary, for technical reason, he's not able to receive email.

[1]http://www.mail-archive.com/linuxppc-dev@lists.ozlabs.org/msg71635.html

 arch/powerpc/include/asm/ppc-opcode.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index eccfc16..0a4a683 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -171,7 +171,7 @@ 
 #define PPC_INST_MULLW			0x7c0001d6
 #define PPC_INST_MULHWU			0x7c000016
 #define PPC_INST_MULLI			0x1c000000
-#define PPC_INST_DIVWU			0x7c0003d6
+#define PPC_INST_DIVWU			0x7c000396
 #define PPC_INST_RLWINM			0x54000000
 #define PPC_INST_RLDICR			0x78000004
 #define PPC_INST_SLW			0x7c000030