diff --git a/stm32mp1.mk b/stm32mp1.mk
index dd8f32a..d6a2ff4 100644
--- a/stm32mp1.mk
+++ b/stm32mp1.mk
@@ -124,6 +124,7 @@
 	AARCH32_SP=optee \
 	DEBUG=$(TFA_DEBUG) \
 	LOG_LEVEL=$(TFA_LOGLVL) \
+	STM32MP15_OPTEE_RSV_SHM=0 \
 	STM32MP_EMMC=1 STM32MP_SDMMC=1 \
 	STM32MP_RAW_NAND=0 STM32MP_SPI_NAND=0 STM32MP_SPI_NOR=0