From 2a552d5e63d7fa602c9a9a0717008737f55625a6 Mon Sep 17 00:00:00 2001
From: Marc Zyngier <Marc.Zyngier@arm.com>
Date: Sat, 6 Oct 2012 17:03:17 +0100
Subject: [PATCH] ARM: 7549/1: HYP: fix boot on some ARM1136 cores

It appears that performing a "movs pc, lr" to force the kernel into
SVC mode on the OMAP2420 (ARM1136) prevents the platform from booting
correctly (change introduced in 80c59da [ARM: virt: allow the kernel
to be entered in HYP mode]).

While the reason it fails is not understood yet (the same code runs
fine on the OMAP2430, ARM1136 as well), partially revert that change
for platforms that do not enter in HYP mode, preserving the new
feature and restoring a working kernel on the OMAP2420.

Reported-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/include/asm/assembler.h | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 683a1e6b6020fb..2ef95813fce00b 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -254,16 +254,17 @@
 	mov	lr , \reg
 	and	lr , lr , #MODE_MASK
 	cmp	lr , #HYP_MODE
-	orr	\reg , \reg , #PSR_A_BIT | PSR_I_BIT | PSR_F_BIT
+	orr	\reg , \reg , #PSR_I_BIT | PSR_F_BIT
 	bic	\reg , \reg , #MODE_MASK
 	orr	\reg , \reg , #SVC_MODE
 THUMB(	orr	\reg , \reg , #PSR_T_BIT	)
-	msr	spsr_cxsf, \reg
-	adr	lr, BSYM(2f)
 	bne	1f
+	orr	\reg, \reg, #PSR_A_BIT
+	adr	lr, BSYM(2f)
+	msr	spsr_cxsf, \reg
 	__MSR_ELR_HYP(14)
 	__ERET
-1:	movs	pc, lr
+1:	msr	cpsr_c, \reg
 2:
 .endm
 
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