diff --git a/encoding.h b/encoding.h
index b71047b6..e11f3147 100644
--- a/encoding.h
+++ b/encoding.h
@@ -151,6 +151,7 @@
 #define MENVCFG_CBIE  0x00000030
 #define MENVCFG_CBCFE 0x00000040
 #define MENVCFG_CBZE  0x00000080
+#define MENVCFG_DTSO  0x00000100
 #define MENVCFG_ADUE  0x2000000000000000
 #define MENVCFG_PBMTE 0x4000000000000000
 #define MENVCFG_STCE  0x8000000000000000
@@ -189,6 +190,7 @@
 #define HENVCFG_CBIE  0x00000030
 #define HENVCFG_CBCFE 0x00000040
 #define HENVCFG_CBZE  0x00000080
+#define HENVCFG_DTSO  0x00000100
 #define HENVCFG_ADUE  0x2000000000000000
 #define HENVCFG_PBMTE 0x4000000000000000
 #define HENVCFG_STCE  0x8000000000000000
@@ -224,6 +226,7 @@
 #define SENVCFG_CBIE  0x00000030
 #define SENVCFG_CBCFE 0x00000040
 #define SENVCFG_CBZE  0x00000080
+#define SENVCFG_DTSO  0x00000100
 
 #define SSTATEEN0_CS   0x00000001
 #define SSTATEEN0_FCSR 0x00000002