openpower/linux/0011-powerpc-Convert-cmp-to-cmpd-in-idle-enter-sequence.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Thu, 6 Oct 2016 13:42:19 +0000
Subject: [PATCH 11/12] powerpc: Convert cmp to cmpd in idle enter sequence

PowerPC's "cmp" instruction has four operands. Normally people write
"cmpw" or "cmpd" for the second cmp operand 0 or 1. But, frequently
people forget, and write "cmp" with just three operands.

With older binutils this is silently accepted as if this was "cmpw",
while often "cmpd" is wanted. With newer binutils GAS will complain
about this for 64-bit code. For 32-bit code it still silently assumes
"cmpw" is what is meant.

In this instance the code comes directly from ISA v2.07, including the
cmp, but cmpd is correct. Backport to stable so that new toolchains can
build old kernels.

Fixes: 948cf67c4726 ("powerpc: Add NAP mode support on Power7 in HV mode")
Cc: stable@vger.kernel.org # v3.0
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
(cherry picked from commit 80f23935cadb1c654e81951f5a8b7ceae0acc1b4)
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
 arch/powerpc/kernel/idle_power7.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S
index 112ccf497562..73f638789a38 100644
--- a/arch/powerpc/kernel/idle_power7.S
+++ b/arch/powerpc/kernel/idle_power7.S
@@ -44,7 +44,7 @@
 	std	r0,0(r1);					\
 	ptesync;						\
 	ld	r0,0(r1);					\
-1:	cmp	cr0,r0,r0;					\
+1:	cmpd	cr0,r0,r0;					\
 	bne	1b;						\
 	IDLE_INST;						\
 	b	.
-- 
2.11.0