diff --git a/plat/arm/board/rde1edge/platform.mk b/plat/arm/board/rde1edge/platform.mk
index 53074f4..0f9dd49 100644
--- a/plat/arm/board/rde1edge/platform.mk
+++ b/plat/arm/board/rde1edge/platform.mk
@@ -58,4 +58,9 @@
    ${CSS_SGI_CHIP_COUNT}.")
 endif
 
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for RD-E1-Edge should always be 0, \
+     currently set to ${CSS_SGI_PLATFORM_VARIANT}.")
+endif
+
 override CTX_INCLUDE_AARCH32_REGS	:= 0
diff --git a/plat/arm/board/rdn1edge/platform.mk b/plat/arm/board/rdn1edge/platform.mk
index d65854f..22ab312 100644
--- a/plat/arm/board/rdn1edge/platform.mk
+++ b/plat/arm/board/rdn1edge/platform.mk
@@ -65,4 +65,9 @@
    set to ${CSS_SGI_CHIP_COUNT}.")
 endif
 
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for RD-N1-Edge should always be 0, \
+     currently set to ${CSS_SGI_PLATFORM_VARIANT}.")
+endif
+
 override CTX_INCLUDE_AARCH32_REGS	:= 0
diff --git a/plat/arm/board/rdn2/platform.mk b/plat/arm/board/rdn2/platform.mk
index 03771dc..bd50fa2 100644
--- a/plat/arm/board/rdn2/platform.mk
+++ b/plat/arm/board/rdn2/platform.mk
@@ -58,3 +58,8 @@
 
 override CTX_INCLUDE_AARCH32_REGS	:= 0
 override ENABLE_AMU			:= 1
+
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for RD-N2 should be 0, currently set to \
+     ${CSS_SGI_PLATFORM_VARIANT}.")
+endif
diff --git a/plat/arm/board/rdv1/platform.mk b/plat/arm/board/rdv1/platform.mk
index 2ffd139..1ae85de 100644
--- a/plat/arm/board/rdv1/platform.mk
+++ b/plat/arm/board/rdv1/platform.mk
@@ -58,3 +58,8 @@
 
 override CTX_INCLUDE_AARCH32_REGS	:= 0
 override ENABLE_AMU			:= 1
+
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for RD-V1 should always be 0, \
+     currently set to ${CSS_SGI_PLATFORM_VARIANT}.")
+endif
diff --git a/plat/arm/board/rdv1mc/platform.mk b/plat/arm/board/rdv1mc/platform.mk
index fb05793..06a2047 100644
--- a/plat/arm/board/rdv1mc/platform.mk
+++ b/plat/arm/board/rdv1mc/platform.mk
@@ -68,3 +68,8 @@
 $(eval $(call TOOL_ADD_PAYLOAD,${NT_FW_CONFIG},--nt-fw-config,${NT_FW_CONFIG}))
 
 override CTX_INCLUDE_AARCH32_REGS	:= 0
+
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for RD-V1-MC should always be 0, \
+     currently set to ${CSS_SGI_PLATFORM_VARIANT}.")
+endif
diff --git a/plat/arm/board/sgi575/platform.mk b/plat/arm/board/sgi575/platform.mk
index 89abcfe..0761b77 100644
--- a/plat/arm/board/sgi575/platform.mk
+++ b/plat/arm/board/sgi575/platform.mk
@@ -58,3 +58,8 @@
  $(error  "Chip count for SGI575 should be 1, currently set to \
    ${CSS_SGI_CHIP_COUNT}.")
 endif
+
+ifneq ($(CSS_SGI_PLATFORM_VARIANT),0)
+ $(error "CSS_SGI_PLATFORM_VARIANT for SGI575 should always be 0,\
+     currently set to ${CSS_SGI_PLATFORM_VARIANT}.")
+endif