diff --git a/include/plat/arm/css/common/css_def.h b/include/plat/arm/css/common/css_def.h
index d599352..dde174c 100644
--- a/include/plat/arm/css/common/css_def.h
+++ b/include/plat/arm/css/common/css_def.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -137,6 +137,8 @@
 #define SSC_DBGCFG_SET		0x14
 #define SSC_DBGCFG_CLR		0x18
 
+#define SPNIDEN_INT_CLR_SHIFT	4
+#define SPNIDEN_SEL_SET_SHIFT	5
 #define SPIDEN_INT_CLR_SHIFT	6
 #define SPIDEN_SEL_SET_SHIFT	7
 
diff --git a/plat/arm/board/juno/juno_security.c b/plat/arm/board/juno/juno_security.c
index 1e64c02..654a7f1 100644
--- a/plat/arm/board/juno/juno_security.c
+++ b/plat/arm/board/juno/juno_security.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -115,6 +115,14 @@
 	/* Drive SPIDEN LOW to disable invasive debug of secure state. */
 	mmio_write_32(SSC_REG_BASE + SSC_DBGCFG_CLR,
 		1U << SPIDEN_INT_CLR_SHIFT);
+
+	/* Set internal drive selection for SPNIDEN. */
+	mmio_write_32(SSC_REG_BASE + SSC_DBGCFG_SET,
+		1U << SPNIDEN_SEL_SET_SHIFT);
+
+	/* Drive SPNIDEN LOW to disable non-invasive debug of secure state. */
+	mmio_write_32(SSC_REG_BASE + SSC_DBGCFG_CLR,
+		1U << SPNIDEN_INT_CLR_SHIFT);
 #endif
 }