[ARM] 2974/1: fix ARM710 swi bug workaround
Patch from Nicolas Pitre
Either no one is using an ARM710 with recent kernels, or all ARM710s
still in use are not afflicted by this swi bug. Nevertheless, the code
to work around the ARM710 swi bug is itself currently buggy since it
uses r8 as a pointer to S_PC while in fact it holds the spsr content
these days. Fix that, and simplify the code as well.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 81d450a..066597f 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -106,15 +106,10 @@
.endm
.Larm700bug:
- ldr r0, [sp, #S_PSR] @ Get calling cpsr
- sub lr, lr, #4
- str lr, [r8]
- msr spsr_cxsf, r0
ldmia sp, {r0 - lr}^ @ Get calling r0 - lr
mov r0, r0
- ldr lr, [sp, #S_PC] @ Get PC
add sp, sp, #S_FRAME_SIZE
- movs pc, lr
+ subs pc, lr, #4
#else
.macro arm710_bug_check, instr, temp
.endm