Please modify the following line to increase the heap size for stmm.
diff --git a/core/arch/arm/kernel/stmm_sp.c b/core/arch/arm/kernel/stmm_sp.c
index bf90eef..b45cc90 100644
--- a/core/arch/arm/kernel/stmm_sp.c
+++ b/core/arch/arm/kernel/stmm_sp.c
@@ -76,7 +76,7 @@
static const uint16_t ffa_storage_id = 4U;
static const unsigned int stmm_stack_size = 4 * SMALL_PAGE_SIZE;
-static const unsigned int stmm_heap_size = 600 * SMALL_PAGE_SIZE;
+static const unsigned int stmm_heap_size = 750 * SMALL_PAGE_SIZE;
You could refer to the following thread about build and update optee.
OP-TEE on Jetson AGX Xavier - Jetson & Embedded Systems / Jetson AGX Xavier - NVIDIA Developer Forums