diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index cdf8600b96..a1e604366b 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1074,7 +1074,8 @@ struct ArchCPU {
     bool prop_lpa2;
 
     /* DCZ blocksize, in log_2(words), ie low 4 bits of DCZID_EL0 */
-    uint32_t dcz_blocksize;
+    uint8_t dcz_blocksize;
+
     uint64_t rvbar_prop; /* Property/input signals.  */
 
     /* Configurable aspects of GIC cpu interface (which is part of the CPU) */