ARM: 8894/1: boot: Replace open-coded nop with macro

This open-coded nop as mov r0, r0 is a development history
artifact.

First commit 615e605fc8c4
("ARM: 6663/1: make Thumb2 kernel entry point more similar
to the ARM one") moved the code around so that the nops
would come before the conditional thumb instructions, as it
turned out that some boot loaders were patching the initial
nop instructions in the kernel. At this point it is clear
that all mov r0,r0 are open-coded nops.

Then commit ea3e289d6ae9 ("ARM: add UEFI stub support")
moved things around and defined __nop for EFI support and
missed this open-coded nop.

commit bc225662515f
("ARM: 8677/1: boot/compressed: fix decompressor header
layout for v7-M") makes all invocations of __nop be wide,
but that is fine, because this is what we want: the
mov r0,r0 is inside ifndef CONFIG_THUMB2_KERNEL.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Acked-by: Roy Franz <rfranz@marvell.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 544450c9067342ead3216020552fd01cf636b8bd..93dffed0ac6e02b476ad82773f56727bf9118c80 100644 (file)
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -169,7 +169,7 @@ start:
                __nop
                .endr
 #ifndef CONFIG_THUMB2_KERNEL
-               mov     r0, r0
+               __nop
 #else
  AR_CLASS(     sub     pc, pc, #3      )       @ A/R: switch to Thumb2 mode
   M_CLASS(     nop.w                   )       @ M: already in Thumb2 mode