openpower/linux/linux-0006-powerpc-kexec-Reset-secondary-cpu-endianess-before-k.patch

From 2d2ab23cbdbbb1907f1f34085c3904efe1979df0 Mon Sep 17 00:00:00 2001
From: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>
Date: Mon, 29 Jun 2015 13:43:51 +1000
Subject: [PATCH 06/18] powerpc/kexec: Reset secondary cpu endianess before
 kexec

If the target kernel does not inlcude the FIXUP_ENDIAN check, coming
from a different-endian kernel will cause the target kernel to panic.
All ppc64 kernels can handle starting in big-endian mode, so return to
big-endian before branching into the target kernel.

This mainly affects pseries as secondaries on powernv are returned to
OPAL.

Signed-off-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
 arch/powerpc/kernel/misc_64.S | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index 4e314b9..6e4168c 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -475,9 +475,18 @@ _GLOBAL(kexec_wait)
 #ifdef CONFIG_KEXEC		/* use no memory without kexec */
 	lwz	r4,0(r5)
 	cmpwi	0,r4,0
-	bnea	0x60
+	beq	99b
+#ifdef CONFIG_PPC_BOOK3S_64
+	li	r10,0x60
+	mfmsr	r11
+	clrrdi	r11,r11,1	/* Clear MSR_LE */
+	mtsrr0	r10
+	mtsrr1	r11
+	rfid
+#else
+	ba	0x60
+#endif
 #endif
-	b	99b
 
 /* this can be in text because we won't change it until we are
  * running in real anyways
-- 
2.5.0