diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index fd8ec7860e..e96d5beb9a 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -1232,7 +1232,7 @@ static MemTxResult smmu_readl(SMMUv3State *s, hwaddr offset,
                               uint64_t *data, MemTxAttrs attrs)
 {
     switch (offset) {
-    case A_IDREGS ... A_IDREGS + 0x1f:
+    case A_IDREGS ... A_IDREGS + 0x2f:
         *data = smmuv3_idreg(offset - A_IDREGS);
         return MEMTX_OK;
     case A_IDR0 ... A_IDR5: