diff --git a/hw/timer/slavio_timer.c b/hw/timer/slavio_timer.c
index 5b2d20cb6a..03e33fc592 100644
--- a/hw/timer/slavio_timer.c
+++ b/hw/timer/slavio_timer.c
@@ -331,6 +331,10 @@ static const MemoryRegionOps slavio_timer_mem_ops = {
     .write = slavio_timer_mem_writel,
     .endianness = DEVICE_NATIVE_ENDIAN,
     .valid = {
+        .min_access_size = 4,
+        .max_access_size = 8,
+    },
+    .impl = {
         .min_access_size = 4,
         .max_access_size = 4,
     },