scripts/make_fit: Speed up operation

The kernel is likely at least 16MB so we may as well use that as a step
size when reallocating space for the FIT in memory. Pack the FIT at the
end, so there is no wasted space.

This reduces the time to pack by an order of magnitude, or so.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://patch.msgid.link/20260106162738.2605574-2-sjg@chromium.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

scripts/make_fit.py

@@ -98,7 +98,7 @@ def setup_fit(fsw, name):
         fsw (libfdt.FdtSw): Object to use for writing
         name (str): Name of kernel image
     """
-    fsw.INC_SIZE = 65536
+    fsw.INC_SIZE = 16 << 20
     fsw.finish_reservemap()
     fsw.begin_node('')
     fsw.property_string('description', f'{name} with devicetree set')
@@ -299,7 +299,9 @@ def build_fit(args):
     finish_fit(fsw, entries)
 
     # Include the kernel itself in the returned file count
-    return fsw.as_fdt().as_bytearray(), seq + 1, size
+    fdt = fsw.as_fdt()
+    fdt.pack()
+    return fdt.as_bytearray(), seq + 1, size
 
 
 def run_make_fit():