1. Simplify payload code and convert it to C
2. Save the FDT pointer to HLS (hart-local storage).
3. Don't use mscratch to pass FDT pointer as it is used for exception handling.
Change-Id: I32bf2a99e07a65358a7f19b899259f0816eb45e8
Signed-off-by: Xiang Wang <wxjstz@126.com>
Signed-off-by: Philipp Hug <philipp@hug.cx>
Reviewed-on: https://review.coreboot.org/c/31179
Reviewed-by: ron minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>