diff --git a/tf-psa-crypto/core/psa_crypto.c b/tf-psa-crypto/core/psa_crypto.c
index df4fc274e8..30dd8292dc 100644
--- a/tf-psa-crypto/core/psa_crypto.c
+++ b/tf-psa-crypto/core/psa_crypto.c
@@ -8184,7 +8184,7 @@ psa_status_t psa_generate_key_iop_complete(
 {
 #if defined(MBEDTLS_ECP_RESTARTABLE)
     psa_status_t status;
-    uint8_t key_data[MBEDTLS_ECP_MAX_MPI] = { 0 };
+    uint8_t key_data[MBEDTLS_ECP_MAX_MPI_BYTES] = { 0 };
     size_t key_len = 0;
 
     if (operation->id == 0 || operation->error_occurred) {
diff --git a/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h b/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
index 533482c0db..98555903e7 100644
--- a/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
+++ b/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
@@ -345,8 +345,8 @@ mbedtls_ecp_group;
 
 #define MBEDTLS_ECP_MAX_BYTES    ((MBEDTLS_ECP_MAX_BITS + 7) / 8)
 #define MBEDTLS_ECP_MAX_PT_LEN   (2 * MBEDTLS_ECP_MAX_BYTES + 1)
-#define MBEDTLS_ECP_MAX_MPI      ((MBEDTLS_ECP_MAX_BYTES + sizeof(mbedtls_mpi_uint)) & \
-                                  ~(sizeof(mbedtls_mpi_uint)-1))
+#define MBEDTLS_ECP_MAX_MPI_BYTES      ((MBEDTLS_ECP_MAX_BYTES + sizeof(mbedtls_mpi_uint)) & \
+                                        ~(sizeof(mbedtls_mpi_uint)-1))
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)