[ARM] 3294/1: don't invalidate individual BTB entries on ARMv6
Patch from Nicolas Pitre
Doing so adds a much larger cost to the loop than the cost implied by
simply invalidating the whole BTB at once.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S
index 72966d9..d921c10 100644
--- a/arch/arm/mm/cache-v6.S
+++ b/arch/arm/mm/cache-v6.S
@@ -92,22 +92,16 @@
* - the Icache does not read data from the write buffer
*/
ENTRY(v6_coherent_user_range)
- bic r0, r0, #CACHE_LINE_SIZE - 1
-1:
+
#ifdef HARVARD_CACHE
- mcr p15, 0, r0, c7, c10, 1 @ clean D line
+ bic r0, r0, #CACHE_LINE_SIZE - 1
+1: mcr p15, 0, r0, c7, c10, 1 @ clean D line
mcr p15, 0, r0, c7, c5, 1 @ invalidate I line
-#endif
- mcr p15, 0, r0, c7, c5, 7 @ invalidate BTB entry
- add r0, r0, #BTB_FLUSH_SIZE
- mcr p15, 0, r0, c7, c5, 7 @ invalidate BTB entry
- add r0, r0, #BTB_FLUSH_SIZE
- mcr p15, 0, r0, c7, c5, 7 @ invalidate BTB entry
- add r0, r0, #BTB_FLUSH_SIZE
- mcr p15, 0, r0, c7, c5, 7 @ invalidate BTB entry
- add r0, r0, #BTB_FLUSH_SIZE
+ add r0, r0, #CACHE_LINE_SIZE
cmp r0, r1
blo 1b
+#endif
+ mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB
#ifdef HARVARD_CACHE
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer