lib: utils: Add a fdt_reserved_memory_fixup() helper

Add a helper routine to insert a child node of the reserved memory
node in the device tree that describes the protected memory region
done by OpenSBI via PMP.

Signed-off-by: Bin Meng <[email protected]>
Reviewed-by: Atish Patra <[email protected]>

1 files changed, 25 insertions, 0 deletions

diff --git a/include/sbi_utils/fdt/fdt_helper.h b/include/sbi_utils/fdt/fdt_helper.h
new file mode 100644
index 00000000..a6c30735
--- /dev/null
+++ b/include/sbi_utils/fdt/fdt_helper.h
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: BSD-2-Clause
+/*
+ * fdt_helper.h - Flat Device Tree manipulation helper routines
+ * Implement helper routines on top of libfdt for OpenSBI usage
+ *
+ * Copyright (C) 2020 Bin Meng <[email protected]>
+ */
+
+#ifndef __FDT_HELPER_H__
+#define __FDT_HELPER_H__
+
+/**
+ * Fix up the reserved memory node in the device tree
+ *
+ * This routine inserts a child node of the reserved memory node in the device
+ * tree that describes the protected memory region done by OpenSBI via PMP.
+ *
+ * It is recommended that platform codes call this helper in their final_init()
+ *
+ * @param fdt: device tree blob
+ * @return zero on success and -ve on failure
+ */
+int fdt_reserved_memory_fixup(void *fdt);
+
+#endif /* __FDT_HELPER_H__ */