[PATCH] ARM: decompressor: remove unused cache flush code

From: Masahiro Yamada
Date: Thu Jan 22 2015 - 00:25:24 EST


As ARM ARM says, the bit 19-16 of ID_MMFR1 is always 0b0000 because
ARMv7 requires a hierarchical cache implementation.
The line "mcr p15, 0, r10, c7, c14, 0" is not reachable.

Moreover, the v7_flush_dcache_all in arch/arm/mm/cache-v7.S does not
check the ID_MMFR1.

Signed-off-by: Masahiro Yamada <yamada.m@xxxxxxxxxxxxxxxx>
---

arch/arm/boot/compressed/head.S | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 9dff614..32f0d79 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -1085,15 +1085,9 @@ __armv6_mmu_cache_flush:
__armv7_mmu_cache_flush:
tst r4, #1
bne iflush
- mrc p15, 0, r10, c0, c1, 5 @ read ID_MMFR1
- tst r10, #0xf << 16 @ hierarchical cache (ARMv7)
+ stmfd sp!, {r0-r7, r9-r11}
mov r10, #0
- beq hierarchical
- mcr p15, 0, r10, c7, c14, 0 @ clean+invalidate D
- b iflush
-hierarchical:
mcr p15, 0, r10, c7, c10, 5 @ DMB
- stmfd sp!, {r0-r7, r9-r11}
mrc p15, 1, r0, c0, c0, 1 @ read clidr
ands r3, r0, #0x7000000 @ extract loc from clidr
mov r3, r3, lsr #23 @ left align loc bit field
--
1.9.1

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