From 8e9c24a2b2e00368262b974d6ea1ac5310570bbe Mon Sep 17 00:00:00 2001 From: Russell King <rmk+kernel@arm.linux.org.uk> Date: Mon, 3 Dec 2012 15:39:43 +0000 Subject: [PATCH] ARM: virt: avoid clobbering lr when forcing svc mode The safe_svcmode_maskall macro is used to ensure that we are running in svc mode, causing an exception return from hvc mode if required. This patch removes the unneeded lr clobber from the macro and operates entirely on the temporary parameter register instead. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> [will: updated comment] Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm/include/asm/assembler.h | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index eb87200aa4b5..05ee9eebad6b 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -246,18 +246,14 @@ * * This macro is intended for forcing the CPU into SVC mode at boot time. * you cannot return to the original mode. - * - * Beware, it also clobers LR. */ .macro safe_svcmode_maskall reg:req #if __LINUX_ARM_ARCH__ >= 6 mrs \reg , cpsr - mov lr , \reg - and lr , lr , #MODE_MASK - cmp lr , #HYP_MODE - orr \reg , \reg , #PSR_I_BIT | PSR_F_BIT + eor \reg, \reg, #HYP_MODE + tst \reg, #MODE_MASK bic \reg , \reg , #MODE_MASK - orr \reg , \reg , #SVC_MODE + orr \reg , \reg , #PSR_I_BIT | PSR_F_BIT | SVC_MODE THUMB( orr \reg , \reg , #PSR_T_BIT ) bne 1f orr \reg, \reg, #PSR_A_BIT