Exit early if size zero for cache helpers
This patch enables cache helper functions `flush_dcache_range`,
`clean_dcache_range` and `invalidate_dcache_range` to exit early
if the size argument specified is zero
Change-Id: I0b63e8f4bd3d47ec08bf2a0b0b9a7ff8a269a9b0
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
diff --git a/lib/aarch32/cache_helpers.S b/lib/aarch32/cache_helpers.S
index 57b6b38..810af0f 100644
--- a/lib/aarch32/cache_helpers.S
+++ b/lib/aarch32/cache_helpers.S
@@ -20,6 +20,9 @@
* This macro can be used for implementing various data cache operations `op`
*/
.macro do_dcache_maintenance_by_mva op, coproc, opc1, CRn, CRm, opc2
+ /* Exit early if size is zero */
+ cmp r1, #0
+ beq exit_loop_\op
dcache_line_size r2, r3
add r1, r0, r1
sub r3, r2, #1
@@ -30,6 +33,7 @@
cmp r0, r1
blo loop_\op
dsb sy
+exit_loop_\op:
bx lr
.endm
diff --git a/lib/aarch64/cache_helpers.S b/lib/aarch64/cache_helpers.S
index eef07a8..9c40b9d 100644
--- a/lib/aarch64/cache_helpers.S
+++ b/lib/aarch64/cache_helpers.S
@@ -20,6 +20,8 @@
* This macro can be used for implementing various data cache operations `op`
*/
.macro do_dcache_maintenance_by_mva op
+ /* Exit early if size is zero */
+ cbz x1, exit_loop_\op
dcache_line_size x2, x3
add x1, x0, x1
sub x3, x2, #1
@@ -30,6 +32,7 @@
cmp x0, x1
b.lo loop_\op
dsb sy
+exit_loop_\op:
ret
.endm
/* ------------------------------------------