diff --git a/include/ivc_core.h b/include/ivc_core.h
index c2a6513..9392699 100644
--- a/include/ivc_core.h
+++ b/include/ivc_core.h
@@ -140,9 +140,10 @@ typedef struct ivc_msg_common {
 	/** message count, used for debug */
 	nveu32_t count;
 
+	/** IVC argument structure */
+	ivc_args args;
+
 	union {
-		/** IVC argument structure */
-		ivc_args args;
 		/** avb algorithm structure */
 		struct osi_core_avb_algorithm avb_algo;
 		/** OSI filter structure */
diff --git a/include/osi_common.h b/include/osi_common.h
index de3e13e..3b55f2d 100644
--- a/include/osi_common.h
+++ b/include/osi_common.h
@@ -211,6 +211,8 @@
 #define OSI_NONE		0U
 #define OSI_NONE_SIGNED		0
 #define OSI_DISABLE		0U
+#define OSI_H_DISABLE		0x10101010U
+#define OSI_H_ENABLE		(~OSI_H_DISABLE)
 
 #define OSI_BIT(nr)             ((nveu32_t)1 << (nr))
 
diff --git a/osi/core/ivc_core.c b/osi/core/ivc_core.c
index c319a16..936f290 100644
--- a/osi/core/ivc_core.c
+++ b/osi/core/ivc_core.c
@@ -149,10 +149,10 @@ static nve32_t ivc_write_phy_reg(struct osi_core_priv_data *const osi_core,
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = write_phy_reg;
-	msg.data.args.arguments[index++] = phyaddr;
-	msg.data.args.arguments[index++] = phyreg;
-	msg.data.args.arguments[index++] = phydata;
-	msg.data.args.count = index;
+	msg.args.arguments[index++] = phyaddr;
+	msg.args.arguments[index++] = phyreg;
+	msg.args.arguments[index++] = phydata;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }
@@ -180,9 +180,9 @@ static nve32_t ivc_read_phy_reg(struct osi_core_priv_data *const osi_core,
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = read_phy_reg;
-	msg.data.args.arguments[index++] = phyaddr;
-	msg.data.args.arguments[index++] = phyreg;
-	msg.data.args.count = index;
+	msg.args.arguments[index++] = phyaddr;
+	msg.args.arguments[index++] = phyreg;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }
@@ -386,9 +386,9 @@ static nve32_t ivc_macsec_enable(struct osi_core_priv_data *const osi_core,
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = en_macsec;
-	msg.data.args.arguments[index] = enable;
+	msg.args.arguments[index] = enable;
 	index++;
-	msg.data.args.count = index;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }
@@ -412,9 +412,9 @@ static nve32_t ivc_macsec_loopback_config(struct osi_core_priv_data *const osi_c
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = loopback_config_macsec;
-	msg.data.args.arguments[index] = enable;
+	msg.args.arguments[index] = enable;
 	index++;
-	msg.data.args.count = index;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }
@@ -473,9 +473,9 @@ static nve32_t ivc_macsec_cipher_config(struct osi_core_priv_data *const osi_cor
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = cipher_config;
-	msg.data.args.arguments[index] = cipher;
+	msg.args.arguments[index] = cipher;
 	index++;
-	msg.data.args.count = index;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }
@@ -564,9 +564,9 @@ static nve32_t ivc_macsec_init(struct osi_core_priv_data *const osi_core,
 	osi_memset(&msg, 0, sizeof(msg));
 
 	msg.cmd = init_macsec;
-	msg.data.args.arguments[index] = mtu;
+	msg.args.arguments[index] = mtu;
 	index++;
-	msg.data.args.count = index;
+	msg.args.count = index;
 
 	return osi_core->osd_ops.ivc_send(osi_core, &msg, sizeof(msg));
 }