diff --git a/tools/tools/git/sanitize.lua b/tools/tools/git/sanitize.lua
new file mode 100644
index 00000000000..a1c9317f372
--- /dev/null
+++ b/tools/tools/git/sanitize.lua
@@ -0,0 +1,53 @@
+-- SPDX-License-Identifier: BSD-2-Clause
+-- Copyright 2026 Warner Losh <imp@FreeBSD.org>
+
+--
+-- Removes all comments, blank lines and extra whitespace from a C header file
+-- and inserts a generated from comment at the top. Generally, this extracts the
+-- smallest subset of the file that describes the interface that is necessary to
+-- interoperate with that software. The user of this program should check the
+-- results, however, to ensure the result minimally describes the public
+-- interface.
+--
+-- When applied to device-tree binding files, this will result in the #defines
+-- being extracted, which are needed to generate the .dtb files, as well as for
+-- code to interpret the .dtb files. The device-tree files must be written this
+-- way to be used for this dual purpose. Other header files may not be so
+-- constrained, which makes review necessary for those context.
+--
+
+--
+-- Useage lua sanitize.lua fn description
+--
+-- fn will be read in, sanitized and the results printed on stdout.
+-- The description will be all remaining args and will be inserted
+-- in the first line comment to describe where the source file was
+-- obtained from.
+--
+
+-- Open the file from the command line
+local fn = arg[1]
+if not fn then
+	print("Usage: sanitize fn")
+	os.exit(1)
+end
+
+-- read it all in
+local f = assert(io.open(fn))
+local content = f:read("*all")
+f:close()
+
+-- Transform
+content = content:gsub("/%*.-%*/", "")		-- Remove block comments, .- is lazy, not greed, match
+content = content:gsub("//[^\n]*", "")		-- Remove single line comments 
+content = content:gsub("%s*\n", "\n")		-- Remove trailing white space
+content = content:gsub("\t+", " ")		-- Convert blocks of tabs to a space
+content = content:gsub("\n+", "\n")		-- Remove blank lines
+content = content:gsub("\n+$", "")		-- Strip blank lines at the end (print adds one)
+content = content:gsub("^\n+", "")		-- Strip leading blank lines
+
+print("/* @" .. "generated from the interface found in " .. fn .. " -- result is in public domain */")
+if arg[2] then
+	print("/* from " .. table.concat(table.pack(table.unpack(arg, 2)), ' ') .. " */")
+end
+print(content)