| #! /bin/bash | 
 |  | 
 | # Copyright (C) 2015 Frank Rowand | 
 | # | 
 | # This program is free software; you can redistribute it and/or modify | 
 | # it under the terms of the GNU General Public License as published by | 
 | # the Free Software Foundation; version 2 of the License. | 
 |  | 
 |  | 
 | usage() { | 
 |  | 
 | 	# use spaces instead of tabs in the usage message | 
 | 	cat >&2 <<eod | 
 |  | 
 | Usage: | 
 |  | 
 |    `basename $0` DTx | 
 |         decompile DTx | 
 |  | 
 |    `basename $0` DTx_1 DTx_2 | 
 |         diff DTx_1 and DTx_2 | 
 |  | 
 |  | 
 |        -f           print full dts in diff (--unified=99999) | 
 |        -h           synonym for --help | 
 |        -help        synonym for --help | 
 |       --help        print this message and exit | 
 |        -s SRCTREE   linux kernel source tree is at path SRCTREE | 
 |                         (default is current directory) | 
 |        -S           linux kernel source tree is at root of current git repo | 
 |        -u           unsorted, do not sort DTx | 
 |  | 
 |  | 
 | Each DTx is processed by the dtc compiler to produce a sorted dts source | 
 | file.  If DTx is a dts source file then it is pre-processed in the same | 
 | manner as done for the compile of the dts source file in the Linux kernel | 
 | build system ('#include' and '/include/' directives are processed). | 
 |  | 
 | If two DTx are provided, the resulting dts source files are diffed. | 
 |  | 
 | If DTx is a directory, it is treated as a DT subtree, such as | 
 |   /proc/device-tree. | 
 |  | 
 | If DTx contains the binary blob magic value in the first four bytes, | 
 |   it is treated as a binary blob (aka .dtb or FDT). | 
 |  | 
 | Otherwise DTx is treated as a dts source file (aka .dts). | 
 |  | 
 |    If this script is not run from the root of the linux source tree, | 
 |    and DTx utilizes '#include' or '/include/' then the path of the | 
 |    linux source tree can be provided by '-s SRCTREE' or '-S' so that | 
 |    include paths will be set properly. | 
 |  | 
 |    The shell variable \${ARCH} must provide the architecture containing | 
 |    the dts source file for include paths to be set properly for '#include' | 
 |    or '/include/' to be processed. | 
 |  | 
 |    If DTx_1 and DTx_2 are in different architectures, then this script | 
 |    may not work since \${ARCH} is part of the include path.  Two possible | 
 |    workarounds: | 
 |  | 
 |       `basename $0` \\ | 
 |           <(ARCH=arch_of_dtx_1 `basename $0` DTx_1) \\ | 
 |           <(ARCH=arch_of_dtx_2 `basename $0` DTx_2) | 
 |  | 
 |       `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts | 
 |       `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts | 
 |       `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts | 
 |       rm tmp_dtx_1.dts tmp_dtx_2.dts | 
 |  | 
 |    If DTx_1 and DTx_2 are in different directories, then this script will | 
 |    add the path of DTx_1 and DTx_2 to the include paths.  If DTx_2 includes | 
 |    a local file that exists in both the path of DTx_1 and DTx_2 then the | 
 |    file in the path of DTx_1 will incorrectly be included.  Possible | 
 |    workaround: | 
 |  | 
 |       `basename $0` DTx_1 >tmp_dtx_1.dts | 
 |       `basename $0` DTx_2 >tmp_dtx_2.dts | 
 |       `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts | 
 |       rm tmp_dtx_1.dts tmp_dtx_2.dts | 
 |  | 
 | eod | 
 | } | 
 |  | 
 |  | 
 | compile_to_dts() { | 
 |  | 
 | 	dtx="$1" | 
 | 	dtc_include="$2" | 
 |  | 
 | 	if [ -d "${dtx}" ] ; then | 
 |  | 
 | 		# -----  input is file tree | 
 |  | 
 | 		if ( ! ${DTC} -I fs ${dtx} ) ; then | 
 | 			exit 3 | 
 | 		fi | 
 |  | 
 | 	elif [ -f "${dtx}" ] && [ -r "${dtx}" ] ; then | 
 |  | 
 | 		magic=`hexdump -n 4 -e '/1 "%02x"' ${dtx}` | 
 | 		if [ "${magic}" = "d00dfeed" ] ; then | 
 |  | 
 | 			# -----  input is FDT (binary blob) | 
 |  | 
 | 			if ( ! ${DTC} -I dtb ${dtx} ) ; then | 
 | 				exit 3 | 
 | 			fi | 
 |  | 
 | 			return | 
 |  | 
 | 		fi | 
 |  | 
 | 		# -----  input is DTS (source) | 
 |  | 
 | 		if ( cpp ${cpp_flags} -x assembler-with-cpp ${dtx} \ | 
 | 			| ${DTC} ${dtc_include} -I dts ) ; then | 
 | 			return | 
 | 		fi | 
 |  | 
 | 		echo ""                                                      >&2 | 
 | 		echo "Possible hints to resolve the above error:"            >&2 | 
 | 		echo "  (hints might not fix the problem)"                   >&2 | 
 |  | 
 | 		hint_given=0 | 
 |  | 
 | 		if [ "${ARCH}" = "" ] ; then | 
 | 			hint_given=1 | 
 | 			echo ""                                              >&2 | 
 | 			echo "  shell variable \$ARCH not set"               >&2 | 
 | 		fi | 
 |  | 
 | 		dtx_arch=`echo "/${dtx}" | sed -e 's|.*/arch/||' -e 's|/.*||'` | 
 |  | 
 | 		if [ "${dtx_arch}" != ""  -a "${dtx_arch}" != "${ARCH}" ] ; then | 
 | 			hint_given=1 | 
 | 			echo ""                                              >&2 | 
 | 			echo "  architecture ${dtx_arch} is in file path,"   >&2 | 
 | 			echo "  but does not match shell variable \$ARCH"    >&2 | 
 | 			echo "  >>\$ARCH<< is: >>${ARCH}<<"                  >&2 | 
 | 		fi | 
 |  | 
 | 		if [ ! -d ${srctree}/arch/${ARCH} ] ; then | 
 | 			hint_given=1 | 
 | 			echo ""                                              >&2 | 
 | 			echo "  ${srctree}/arch/${ARCH}/ does not exist"     >&2 | 
 | 			echo "  Is \$ARCH='${ARCH}' correct?"                >&2 | 
 | 			echo "  Possible fix: use '-s' option"               >&2 | 
 |  | 
 | 			git_root=`git rev-parse --show-toplevel 2>/dev/null` | 
 | 			if [ -d ${git_root}/arch/ ] ; then | 
 | 				echo "  Possible fix: use '-S' option"       >&2 | 
 | 			fi | 
 | 		fi | 
 |  | 
 | 		if [ $hint_given = 0 ] ; then | 
 | 			echo ""                                              >&2 | 
 | 			echo "  No hints available."                         >&2 | 
 | 		fi | 
 |  | 
 | 		echo ""                                                      >&2 | 
 |  | 
 | 		exit 3 | 
 |  | 
 | 	else | 
 | 		echo ""                                                     >&2 | 
 | 		echo "ERROR: ${dtx} does not exist or is not readable"      >&2 | 
 | 		echo ""                                                     >&2 | 
 | 		exit 2 | 
 | 	fi | 
 |  | 
 | } | 
 |  | 
 |  | 
 | # -----  start of script | 
 |  | 
 | cmd_diff=0 | 
 | diff_flags="-u" | 
 | dtx_file_1="" | 
 | dtx_file_2="" | 
 | dtc_sort="-s" | 
 | help=0 | 
 | srctree="" | 
 |  | 
 |  | 
 | while [ $# -gt 0 ] ; do | 
 |  | 
 | 	case $1 in | 
 |  | 
 | 	-f ) | 
 | 		diff_flags="--unified=999999" | 
 | 		shift | 
 | 		;; | 
 |  | 
 | 	-h | -help | --help ) | 
 | 		help=1 | 
 | 		shift | 
 | 		;; | 
 |  | 
 | 	-s ) | 
 | 		srctree="$2" | 
 | 		shift 2 | 
 | 		;; | 
 |  | 
 | 	-S ) | 
 | 		git_root=`git rev-parse --show-toplevel 2>/dev/null` | 
 | 		srctree="${git_root}" | 
 | 		shift | 
 | 		;; | 
 |  | 
 | 	-u ) | 
 | 		dtc_sort="" | 
 | 		shift | 
 | 		;; | 
 |  | 
 | 	*) | 
 | 		if [ "${dtx_file_1}"  = "" ] ; then | 
 | 			dtx_file_1="$1" | 
 | 		elif [ "${dtx_file_2}" = "" ] ; then | 
 | 			dtx_file_2="$1" | 
 | 		else | 
 | 			echo ""                                             >&2 | 
 | 			echo "ERROR: Unexpected parameter: $1"              >&2 | 
 | 			echo ""                                             >&2 | 
 | 			exit 2 | 
 | 		fi | 
 | 		shift | 
 | 		;; | 
 |  | 
 | 	esac | 
 |  | 
 | done | 
 |  | 
 | if [ "${srctree}" = "" ] ; then | 
 | 	srctree="." | 
 | fi | 
 |  | 
 | if [ "${dtx_file_2}" != "" ]; then | 
 | 	cmd_diff=1 | 
 | fi | 
 |  | 
 | if (( ${help} )) ; then | 
 | 	usage | 
 | 	exit 1 | 
 | fi | 
 |  | 
 | # this must follow check for ${help} | 
 | if [ "${dtx_file_1}" = "" ]; then | 
 | 	echo ""                                                             >&2 | 
 | 	echo "ERROR: parameter DTx required"                                >&2 | 
 | 	echo ""                                                             >&2 | 
 | 	exit 2 | 
 | fi | 
 |  | 
 |  | 
 | # -----  prefer dtc from linux kernel, allow fallback to dtc in $PATH | 
 |  | 
 | if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then | 
 | 	__KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}" | 
 | elif [ "${KBUILD_OUTPUT}" = "" ] ; then | 
 | 	__KBUILD_OUTPUT="." | 
 | else | 
 | 	__KBUILD_OUTPUT="${KBUILD_OUTPUT}" | 
 | fi | 
 |  | 
 | DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc" | 
 |  | 
 | if [ ! -x ${DTC} ] ; then | 
 | 	__DTC="dtc" | 
 | 	if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then | 
 | 		make_command=' | 
 |          make scripts' | 
 | 	else | 
 | 		make_command=' | 
 |          Enable CONFIG_DTC in the kernel configuration | 
 |          make scripts' | 
 | 	fi | 
 | 	if ( ! which ${__DTC} >/dev/null ) ; then | 
 |  | 
 | 		# use spaces instead of tabs in the error message | 
 | 		cat >&2 <<eod | 
 |  | 
 | ERROR: unable to find a 'dtc' program | 
 |  | 
 |    Preferred 'dtc' (built from Linux kernel source tree) was not found or | 
 |    is not executable. | 
 |  | 
 |       'dtc' is: ${DTC} | 
 |  | 
 |       If it does not exist, create it from the root of the Linux source tree: | 
 | ${make_command} | 
 |  | 
 |       If not at the root of the Linux kernel source tree -s SRCTREE or -S | 
 |       may need to be specified to find 'dtc'. | 
 |  | 
 |       If 'O=\${dir}' is specified in your Linux builds, this script requires | 
 |       'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH | 
 |       before running. | 
 |  | 
 |       If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run | 
 |       this script from the root of the Linux kernel source tree is required. | 
 |  | 
 |    Fallback '${__DTC}' was also not in \${PATH} or is not executable. | 
 |  | 
 | eod | 
 | 		exit 2 | 
 | 	fi | 
 | 	DTC=${__DTC} | 
 | fi | 
 |  | 
 |  | 
 | # -----  cpp and dtc flags same as for linux source tree build of .dtb files, | 
 | #        plus directories of the dtx file(s) | 
 |  | 
 | dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`" | 
 |  | 
 | dtx_path_2_dtc_include="" | 
 | if (( ${cmd_diff} )) ; then | 
 | 	dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`" | 
 | fi | 
 |  | 
 | cpp_flags="\ | 
 | 	-nostdinc                                  \ | 
 | 	-I${srctree}/scripts/dtc/include-prefixes  \ | 
 | 	-undef -D__DTS__" | 
 |  | 
 | DTC="\ | 
 | 	${DTC}                                     \ | 
 | 	-i ${srctree}/scripts/dtc/include-prefixes \ | 
 | 	-O dts -qq -f ${dtc_sort} -o -" | 
 |  | 
 |  | 
 | # -----  do the diff or decompile | 
 |  | 
 | if (( ${cmd_diff} )) ; then | 
 |  | 
 | 	diff ${diff_flags} --label "${dtx_file_1}" --label "${dtx_file_2}" \ | 
 | 		<(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \ | 
 | 		<(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}") | 
 |  | 
 | else | 
 |  | 
 | 	compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}" | 
 |  | 
 | fi |