diff --git a/firmware/target/arm/mmu-arm.S b/firmware/target/arm/mmu-arm.S
index 00e4c2b..a43af24 100644
--- a/firmware/target/arm/mmu-arm.S
+++ b/firmware/target/arm/mmu-arm.S
@@ -274,6 +274,11 @@ clean_dcache_range:
     .global     cpucache_flush      @ Alias
 clean_dcache:
 cpucache_flush:
+#if ARM_ARCH == 5
+    mrc     p15, 0, r15, c7, c10, 3 @ test and clean dcache
+    bne     clean_dcache
+    mov     r0, #0
+#else
     @ Index format: 31:26 = index, 7:5 = segment, remainder = SBZ
     mov     r0, #0x00000000         @
 1:  @ clean_start                   @
@@ -295,6 +300,7 @@ cpucache_flush:
     sub     r0, r0, #0x000000e0     @
     adds    r0, r0, #0x04000000     @ will wrap to zero at loop end
     bne     1b @ clean_start        @
+#endif /* ARM_ARCH == 5 */
     mcr     p15, 0, r0, c7, c10, 4  @ Drain write buffer
     bx      lr                      @ 
     .size   clean_dcache, .-clean_dcache
@@ -309,6 +315,11 @@ cpucache_flush:
     .global     invalidate_dcache
     .type       invalidate_dcache, %function
 invalidate_dcache:
+#if ARM_ARCH == 5
+    mrc     p15, 0, r15, c7, c14, 3 @ test, clean and invalidate dcache
+    bne     invalidate_dcache
+    mov     r0, #0
+#else
     @ Index format: 31:26 = index, 7:5 = segment, remainder = SBZ
     mov     r0, #0x00000000         @
 1:  @ inv_start                     @
@@ -330,6 +341,7 @@ invalidate_dcache:
     sub     r0, r0, #0x000000e0     @
     adds    r0, r0, #0x04000000     @ will wrap to zero at loop end
     bne     1b @ inv_start          @
+#endif /* ARM_ARCH == 5 */
     mcr     p15, 0, r0, c7, c10, 4  @ Drain write buffer
     bx      lr                      @
     .size   invalidate_dcache, .-invalidate_dcache