diff --git a/artiq/runtime/mailbox.c b/artiq/runtime/mailbox.c
index 98e49045b..1faa6d374 100644
--- a/artiq/runtime/mailbox.c
+++ b/artiq/runtime/mailbox.c
@@ -10,25 +10,6 @@
 
 static unsigned int last_transmission;
 
-static void _flush_cpu_dcache(void)
-{
-    unsigned long dccfgr;
-    unsigned long cache_set_size;
-    unsigned long cache_ways;
-    unsigned long cache_block_size;
-    unsigned long cache_size;
-    int i;
-
-    dccfgr = mfspr(SPR_DCCFGR);
-    cache_ways = 1 << (dccfgr & SPR_ICCFGR_NCW);
-    cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
-    cache_block_size = (dccfgr & SPR_DCCFGR_CBS) ? 32 : 16;
-    cache_size = cache_set_size * cache_ways * cache_block_size;
-
-    for (i = 0; i < cache_size; i += cache_block_size)
-        mtspr(SPR_DCBIR, i);
-}
-
 void mailbox_send(void *ptr)
 {
     last_transmission = (unsigned int)ptr;
@@ -58,7 +39,7 @@ void *mailbox_receive(void)
         return NULL;
     else {
         if(r) {
-            _flush_cpu_dcache();
+            flush_cpu_dcache();
         }
         return (void *)r;
     }