diff --git a/recipes-security/optee/optee-os-stm32mp-archiver.inc b/recipes-security/optee/optee-os-stm32mp-archiver.inc
index a92e506..3f9cb73 100644
--- a/recipes-security/optee/optee-os-stm32mp-archiver.inc
+++ b/recipes-security/optee/optee-os-stm32mp-archiver.inc
@@ -20,6 +20,9 @@ DEPLOYDIR ?= \$(SRC_PATH)/../deploy
 
 # Set default optee-os config
 CFG_EMBED_DTB_SOURCE_FILE ?= ${OPTEE_CONF}
+OPTEE_DRAMSIZE ?=
+OPTEE_DRAMSIZE_EV ?= 0x40000000
+OPTEE_DRAMSIZE_DK ?= 0x20000000
 
 # Remove default variables
 LDFLAGS =
@@ -28,6 +31,26 @@ CPPFLAGS =
 # Define default make options
 EXTRA_OEMAKE = $(echo "${EXTRA_OEMAKE}" | sed "s|LIBGCC_LOCATE_CFLAGS=[^ ]* |LIBGCC_LOCATE_CFLAGS=\$(KCFLAGS) |")
 
+# Check that provided devicetree file follow the default naming rules:
+#   devicetree name should contains the original stm32mp devicetree name to allow proper auto-configuration
+check_dt:= \$(shell \\
+	for dt in \$(CFG_EMBED_DTB_SOURCE_FILE); do \\
+		match_naming="\$\$dt" ; \\
+		for stdt in ${STM32MP_DEVICETREE} ; do \\
+			if [ "\$\$(echo \$\$dt | grep -cE "\$\$stdt\$\$|\$\$stdt-")" -eq 1 ]; then \\
+				match_naming="" ; \\
+				break ; \\
+			fi ; \\
+		done ; \\
+		echo \$\$match_naming ; \\
+	done)
+
+ifneq (\$(check_dt),)
+ifeq (\$(OPTEE_DRAMSIZE),)
+\$(error Devicetree name "\$(check_dt)" is not compatible with optee-os-stm32mp auto configuration switch: you should configure OPTEE_DRAMSIZE by yourself)
+endif
+endif
+
 # Set dependencies list for building all
 DEPS = optee
 DEPS += fip
@@ -36,6 +59,21 @@ help:
 	@echo
 	@echo "OPTEE-OS configuration:"
 	@echo "  CFG_EMBED_DTB_SOURCE_FILE = \$(CFG_EMBED_DTB_SOURCE_FILE)"
+	@echo "  DRAM size setting:"
+	@for dt in \$(CFG_EMBED_DTB_SOURCE_FILE); do \\
+		if [ -n "\$(OPTEE_DRAMSIZE)" ]; then \
+			dramsize_config="OPTEE_DRAMSIZE = \$(OPTEE_DRAMSIZE)" ; \
+		else \
+			dramsize_config="OPTEE_DRAMSIZE_EV = \$(OPTEE_DRAMSIZE_EV)" ; \\
+			for dk in ${STM32MP_DT_FILES_DK} ; do \\
+				if [ "\$\$(echo \$\$dt | grep -cE "\$\$dk\$\$|\$\$dk-")" -eq 1 ]; then \\
+					dramsize_config="OPTEE_DRAMSIZE_DK = \$(OPTEE_DRAMSIZE_DK)" ; \\
+					break ; \\
+				fi ; \\
+			done ; \\
+		fi ; \\
+		echo "    \$\$dt : \$\$dramsize_config" ; \\
+	done
 	@echo
 	@echo "OPTEE-OS folder configuration:"
 	@echo "  SRC_PATH  = \$(SRC_PATH)"
@@ -46,7 +84,9 @@ help:
 	@echo "  Do not forget to set FIP deploydir folders (such as FIP_DEPLOYDIR_ROOT) to provide path to needed binaries"
 	@echo
 	@echo "Available targets:"
-	@echo "  all   : build OPTEE-OS binaries for defined config(s)"
+	@echo "  all   : default target to build all binaries for defined config(s)"
+	@echo "  fip   : build FIP binaries for defined config(s)"
+	@echo "  optee : build OPTEE-OS binaries for defined config(s)"
 	@echo "  clean : clean build directories from generated files"
 	@echo
 
@@ -55,9 +95,29 @@ all: \$(DEPS)
 optee:
 	@mkdir -p \$(DEPLOYDIR)
 	@mkdir -p \$(DEPLOYDIR)/debug
-	@if test -n "\$(CFG_EMBED_DTB_SOURCE_FILE)" ; then \\
-		for dt in \$(CFG_EMBED_DTB_SOURCE_FILE) ; do \\
-			\$(MAKE) \$(EXTRA_OEMAKE) -C \$(SRC_PATH) PREFIX=\$(SDKTARGETSYSROOT) O=\$(BLD_PATH)/\$\$dt CFG_EMBED_DTB_SOURCE_FILE=\$\$dt.dts ; \\
+	@if [ -n "\$(CFG_EMBED_DTB_SOURCE_FILE)" ]; then \\
+		for dt in \$(CFG_EMBED_DTB_SOURCE_FILE); do \\
+			# Configure SOC switch \\
+			soc_extra="" ; \\
+			for soc in ${STM32MP_SOC_NAME} ; do \\
+				if [ "\$\$(echo \$\$dt | grep -c \$\$soc)" -eq 1 ]; then \\
+					soc_extra="\$\$(echo CFG_\$\$soc | tr a-z A-Z)=y" ; \\
+					break ; \\
+				fi ; \\
+			done ; \\
+			# Configure DRAM_SIZE switch \\
+			if [ -n "\$(OPTEE_DRAMSIZE)" ]; then \\
+				dramsize="\$(OPTEE_DRAMSIZE)" ; \\
+			else \\
+				dramsize="\$(OPTEE_DRAMSIZE_EV)" ; \\
+				for dk in ${STM32MP_DT_FILES_DK} ; do \\
+					if [ "\$\$(echo \$\$dt | grep -cE "\$\$dk\$\$|\$\$dk-")" -eq 1 ]; then \\
+						dramsize="\$(OPTEE_DRAMSIZE_DK)" ; \\
+						break ; \\
+					fi ; \\
+				done ; \\
+			fi ; \\
+			\$(MAKE) \$(EXTRA_OEMAKE) -C \$(SRC_PATH) PREFIX=\$(SDKTARGETSYSROOT) O=\$(BLD_PATH)/\$\$dt CFG_EMBED_DTB_SOURCE_FILE=\$\$dt.dts CFG_DRAM_SIZE=\$\$dramsize \$\$soc_extra ; \\
 			# Copy binary files with explicit name \\
 			cp \$(BLD_PATH)/\$\$dt/core/${OPTEE_HEADER}.${OPTEE_SUFFIX} \$(DEPLOYDIR)/${OPTEE_HEADER}-\$\$dt.${OPTEE_SUFFIX} ; \\
 			cp \$(BLD_PATH)/\$\$dt/core/${OPTEE_PAGER}.${OPTEE_SUFFIX} \$(DEPLOYDIR)/${OPTEE_PAGER}-\$\$dt.${OPTEE_SUFFIX} ; \\
diff --git a/recipes-security/optee/optee-os/README.HOW_TO.txt b/recipes-security/optee/optee-os/README.HOW_TO.txt
index e694ff1..b4fc522 100644
--- a/recipes-security/optee/optee-os/README.HOW_TO.txt
+++ b/recipes-security/optee/optee-os/README.HOW_TO.txt
@@ -104,10 +104,15 @@ Since OpenSTLinux activates FIP by default, FIP_artifacts directory path must be
   - In case of using SOURCES-xxxx.tar.gz of Developer package the FIP_DEPLOYDIR_ROOT must be set as below:
     $> export FIP_DEPLOYDIR_ROOT=$PWD/../../FIP_artifacts
 
-To compile optee-os source code
+To compile optee-os source code with default embedded config:
     $> make -f $PWD/../Makefile.sdk all
-or for a specific config :
-    $ make -f $PWD/../Makefile.sdk CFG_EMBED_DTB_SOURCE_FILE=stm32mp157c-ev1 all
+You can check the configuration throught 'help' target:
+    $ make -f $PWD/../Makefile.sdk help
+
+To compile only one of the provided devicetree:
+    $ make -f $PWD/../Makefile.sdk CFG_EMBED_DTB_SOURCE_FILE=stm32mp157f-ev1 all
+For a specific devicetree file you need to force not only the devicetree but also the DRAM size settings:
+    $ make -f $PWD/../Makefile.sdk CFG_EMBED_DTB_SOURCE_FILE=<your_devicetree> OPTEE_DRAMSIZE=<dram_size_value_in_hexadecimal> all
 
 By default, the build results for this component are available in $PWD/../deploy directory.
 If needed, this deploy directory can be specified by added "DEPLOYDIR=<your_deploy_dir_path>" compilation option to the build command line above.