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diff --git a/scripts/make_fit.py b/scripts/make_fit.py
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+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright 2024 Google LLC
+# Written by Simon Glass <sjg@chromium.org>
+#
+
+"""Build a FIT containing a lot of devicetree files
+
+Usage:
+    make_fit.py -A arm64 -n 'Linux-6.6' -O linux
+        -o arch/arm64/boot/image.fit -k /tmp/kern/arch/arm64/boot/image.itk
+        @arch/arm64/boot/dts/dtbs-list -E -c gzip
+
+Creates a FIT containing the supplied kernel and a set of devicetree files,
+either specified individually or listed in a file (with an '@' prefix).
+
+Use -E to generate an external FIT (where the data is placed after the
+FIT data structure). This allows parsing of the data without loading
+the entire FIT.
+
+Use -c to compress the data, using bzip2, gzip, lz4, lzma, lzo and
+zstd algorithms.
+
+The resulting FIT can be booted by bootloaders which support FIT, such
+as U-Boot, Linuxboot, Tianocore, etc.
+
+Note that this tool does not yet support adding a ramdisk / initrd.
+"""
+
+import argparse
+import collections
+import os
+import subprocess
+import sys
+import tempfile
+import time
+
+import libfdt
+
+
+# Tool extension and the name of the command-line tools
+CompTool = collections.namedtuple('CompTool', 'ext,tools')
+
+COMP_TOOLS = {
+    'bzip2': CompTool('.bz2', 'bzip2'),
+    'gzip': CompTool('.gz', 'pigz,gzip'),
+    'lz4': CompTool('.lz4', 'lz4'),
+    'lzma': CompTool('.lzma', 'lzma'),
+    'lzo': CompTool('.lzo', 'lzop'),
+    'zstd': CompTool('.zstd', 'zstd'),
+}
+
+
+def parse_args():
+    """Parse the program ArgumentParser
+
+    Returns:
+        Namespace object containing the arguments
+    """
+    epilog = 'Build a FIT from a directory tree containing .dtb files'
+    parser = argparse.ArgumentParser(epilog=epilog, fromfile_prefix_chars='@')
+    parser.add_argument('-A', '--arch', type=str, required=True,
+          help='Specifies the architecture')
+    parser.add_argument('-c', '--compress', type=str, default='none',
+          help='Specifies the compression')
+    parser.add_argument('-E', '--external', action='store_true',
+          help='Convert the FIT to use external data')
+    parser.add_argument('-n', '--name', type=str, required=True,
+          help='Specifies the name')
+    parser.add_argument('-o', '--output', type=str, required=True,
+          help='Specifies the output file (.fit)')
+    parser.add_argument('-O', '--os', type=str, required=True,
+          help='Specifies the operating system')
+    parser.add_argument('-k', '--kernel', type=str, required=True,
+          help='Specifies the (uncompressed) kernel input file (.itk)')
+    parser.add_argument('-v', '--verbose', action='store_true',
+                        help='Enable verbose output')
+    parser.add_argument('dtbs', type=str, nargs='*',
+          help='Specifies the devicetree files to process')
+
+    return parser.parse_args()
+
+
+def setup_fit(fsw, name):
+    """Make a start on writing the FIT
+
+    Outputs the root properties and the 'images' node
+
+    Args:
+        fsw (libfdt.FdtSw): Object to use for writing
+        name (str): Name of kernel image
+    """
+    fsw.INC_SIZE = 65536
+    fsw.finish_reservemap()
+    fsw.begin_node('')
+    fsw.property_string('description', f'{name} with devicetree set')
+    fsw.property_u32('#address-cells', 1)
+
+    fsw.property_u32('timestamp', int(time.time()))
+    fsw.begin_node('images')
+
+
+def write_kernel(fsw, data, args):
+    """Write out the kernel image
+
+    Writes a kernel node along with the required properties
+
+    Args:
+        fsw (libfdt.FdtSw): Object to use for writing
+        data (bytes): Data to write (possibly compressed)
+        args (Namespace): Contains necessary strings:
+            arch: FIT architecture, e.g. 'arm64'
+            fit_os: Operating Systems, e.g. 'linux'
+            name: Name of OS, e.g. 'Linux-6.6.0-rc7'
+            compress: Compression algorithm to use, e.g. 'gzip'
+    """
+    with fsw.add_node('kernel'):
+        fsw.property_string('description', args.name)
+        fsw.property_string('type', 'kernel_noload')
+        fsw.property_string('arch', args.arch)
+        fsw.property_string('os', args.os)
+        fsw.property_string('compression', args.compress)
+        fsw.property('data', data)
+        fsw.property_u32('load', 0)
+        fsw.property_u32('entry', 0)
+
+
+def finish_fit(fsw, entries):
+    """Finish the FIT ready for use
+
+    Writes the /configurations node and subnodes
+
+    Args:
+        fsw (libfdt.FdtSw): Object to use for writing
+        entries (list of tuple): List of configurations:
+            str: Description of model
+            str: Compatible stringlist
+    """
+    fsw.end_node()
+    seq = 0
+    with fsw.add_node('configurations'):
+        for model, compat in entries:
+            seq += 1
+            with fsw.add_node(f'conf-{seq}'):
+                fsw.property('compatible', bytes(compat))
+                fsw.property_string('description', model)
+                fsw.property_string('fdt', f'fdt-{seq}')
+                fsw.property_string('kernel', 'kernel')
+    fsw.end_node()
+
+
+def compress_data(inf, compress):
+    """Compress data using a selected algorithm
+
+    Args:
+        inf (IOBase): Filename containing the data to compress
+        compress (str): Compression algorithm, e.g. 'gzip'
+
+    Return:
+        bytes: Compressed data
+    """
+    if compress == 'none':
+        return inf.read()
+
+    comp = COMP_TOOLS.get(compress)
+    if not comp:
+        raise ValueError(f"Unknown compression algorithm '{compress}'")
+
+    with tempfile.NamedTemporaryFile() as comp_fname:
+        with open(comp_fname.name, 'wb') as outf:
+            done = False
+            for tool in comp.tools.split(','):
+                try:
+                    subprocess.call([tool, '-c'], stdin=inf, stdout=outf)
+                    done = True
+                    break
+                except FileNotFoundError:
+                    pass
+            if not done:
+                raise ValueError(f'Missing tool(s): {comp.tools}\n')
+            with open(comp_fname.name, 'rb') as compf:
+                comp_data = compf.read()
+    return comp_data
+
+
+def output_dtb(fsw, seq, fname, arch, compress):
+    """Write out a single devicetree to the FIT
+
+    Args:
+        fsw (libfdt.FdtSw): Object to use for writing
+        seq (int): Sequence number (1 for first)
+        fmame (str): Filename containing the DTB
+        arch: FIT architecture, e.g. 'arm64'
+        compress (str): Compressed algorithm, e.g. 'gzip'
+
+    Returns:
+        tuple:
+            str: Model name
+            bytes: Compatible stringlist
+    """
+    with fsw.add_node(f'fdt-{seq}'):
+        # Get the compatible / model information
+        with open(fname, 'rb') as inf:
+            data = inf.read()
+        fdt = libfdt.FdtRo(data)
+        model = fdt.getprop(0, 'model').as_str()
+        compat = fdt.getprop(0, 'compatible')
+
+        fsw.property_string('description', model)
+        fsw.property_string('type', 'flat_dt')
+        fsw.property_string('arch', arch)
+        fsw.property_string('compression', compress)
+        fsw.property('compatible', bytes(compat))
+
+        with open(fname, 'rb') as inf:
+            compressed = compress_data(inf, compress)
+        fsw.property('data', compressed)
+    return model, compat
+
+
+def build_fit(args):
+    """Build the FIT from the provided files and arguments
+
+    Args:
+        args (Namespace): Program arguments
+
+    Returns:
+        tuple:
+            bytes: FIT data
+            int: Number of configurations generated
+            size: Total uncompressed size of data
+    """
+    seq = 0
+    size = 0
+    fsw = libfdt.FdtSw()
+    setup_fit(fsw, args.name)
+    entries = []
+
+    # Handle the kernel
+    with open(args.kernel, 'rb') as inf:
+        comp_data = compress_data(inf, args.compress)
+    size += os.path.getsize(args.kernel)
+    write_kernel(fsw, comp_data, args)
+
+    for fname in args.dtbs:
+        # Ignore overlay (.dtbo) files
+        if os.path.splitext(fname)[1] == '.dtb':
+            seq += 1
+            size += os.path.getsize(fname)
+            model, compat = output_dtb(fsw, seq, fname, args.arch, args.compress)
+            entries.append([model, compat])
+
+    finish_fit(fsw, entries)
+
+    # Include the kernel itself in the returned file count
+    return fsw.as_fdt().as_bytearray(), seq + 1, size
+
+
+def run_make_fit():
+    """Run the tool's main logic"""
+    args = parse_args()
+
+    out_data, count, size = build_fit(args)
+    with open(args.output, 'wb') as outf:
+        outf.write(out_data)
+
+    ext_fit_size = None
+    if args.external:
+        mkimage = os.environ.get('MKIMAGE', 'mkimage')
+        subprocess.check_call([mkimage, '-E', '-F', args.output],
+                              stdout=subprocess.DEVNULL)
+
+        with open(args.output, 'rb') as inf:
+            data = inf.read()
+        ext_fit = libfdt.FdtRo(data)
+        ext_fit_size = ext_fit.totalsize()
+
+    if args.verbose:
+        comp_size = len(out_data)
+        print(f'FIT size {comp_size:#x}/{comp_size / 1024 / 1024:.1f} MB',
+              end='')
+        if ext_fit_size:
+            print(f', header {ext_fit_size:#x}/{ext_fit_size / 1024:.1f} KB',
+                  end='')
+        print(f', {count} files, uncompressed {size / 1024 / 1024:.1f} MB')
+
+
+if __name__ == "__main__":
+    sys.exit(run_make_fit())