arm: init: export prev_bl_fdt_addr

When booting U-Boot on board with a locked down first-stage bootloader,
we emulate the Linux boot header. By passing the U-Boot FDT through this
first-stage bootloader and retrieving it afterwards we can pre-populate
the memory nodes and other info like the KASLR address.

Add a function to export the FDT addr so that boards can use it over the
built-in FDT.

Don't check is_addr_accessible() here because we might not yet have a
valid mem_map if it's going to be populated from the FDT, let the board
do their own validation instead.

Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
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This patch has no dependencies

Cc: Simon Glass <sjg@chromium.org>
2 files changed