1#! /bin/bash 2# SPDX-License-Identifier: GPL-2.0-only 3 4# Copyright (C) 2015 Frank Rowand 5# 6 7 8usage() { 9 10 # use spaces instead of tabs in the usage message 11 cat >&2 <<eod 12 13Usage: 14 15 `basename $0` DTx 16 decompile DTx 17 18 `basename $0` DTx_1 DTx_2 19 diff DTx_1 and DTx_2 20 21 22 --annotate synonym for -T 23 -f print full dts in diff (--unified=99999) 24 -h synonym for --help 25 -help synonym for --help 26 --help print this message and exit 27 -s SRCTREE linux kernel source tree is at path SRCTREE 28 (default is current directory) 29 -S linux kernel source tree is at root of current git repo 30 -T Annotate output .dts with input source file and line (-T -T for more details) 31 -u unsorted, do not sort DTx 32 33 34Each DTx is processed by the dtc compiler to produce a sorted dts source 35file. If DTx is a dts source file then it is pre-processed in the same 36manner as done for the compile of the dts source file in the Linux kernel 37build system ('#include' and '/include/' directives are processed). 38 39If two DTx are provided, the resulting dts source files are diffed. 40 41If DTx is a directory, it is treated as a DT subtree, such as 42 /proc/device-tree. 43 44If DTx contains the binary blob magic value in the first four bytes, 45 it is treated as a binary blob (aka .dtb or FDT). 46 47Otherwise DTx is treated as a dts source file (aka .dts). 48 49 If this script is not run from the root of the linux source tree, 50 and DTx utilizes '#include' or '/include/' then the path of the 51 linux source tree can be provided by '-s SRCTREE' or '-S' so that 52 include paths will be set properly. 53 54 The shell variable \${ARCH} must provide the architecture containing 55 the dts source file for include paths to be set properly for '#include' 56 or '/include/' to be processed. 57 58 If DTx_1 and DTx_2 are in different architectures, then this script 59 may not work since \${ARCH} is part of the include path. Two possible 60 workarounds: 61 62 `basename $0` \\ 63 <(ARCH=arch_of_dtx_1 `basename $0` DTx_1) \\ 64 <(ARCH=arch_of_dtx_2 `basename $0` DTx_2) 65 66 `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts 67 `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts 68 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 69 rm tmp_dtx_1.dts tmp_dtx_2.dts 70 71 If DTx_1 and DTx_2 are in different directories, then this script will 72 add the path of DTx_1 and DTx_2 to the include paths. If DTx_2 includes 73 a local file that exists in both the path of DTx_1 and DTx_2 then the 74 file in the path of DTx_1 will incorrectly be included. Possible 75 workaround: 76 77 `basename $0` DTx_1 >tmp_dtx_1.dts 78 `basename $0` DTx_2 >tmp_dtx_2.dts 79 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 80 rm tmp_dtx_1.dts tmp_dtx_2.dts 81 82eod 83} 84 85 86compile_to_dts() { 87 88 dtx="$1" 89 dtc_include="$2" 90 91 if [ -d "${dtx}" ] ; then 92 93 # ----- input is file tree 94 95 if ( ! ${DTC} -I fs ${dtx} ) ; then 96 exit 3 97 fi 98 99 elif [ -f "${dtx}" ] && [ -r "${dtx}" ] ; then 100 101 magic=`hexdump -n 4 -e '/1 "%02x"' ${dtx}` 102 if [ "${magic}" = "d00dfeed" ] ; then 103 104 # ----- input is FDT (binary blob) 105 106 if ( ! ${DTC} -I dtb ${dtx} ) ; then 107 exit 3 108 fi 109 110 return 111 112 fi 113 114 # ----- input is DTS (source) 115 116 if ( cpp ${cpp_flags} -x assembler-with-cpp ${dtx} \ 117 | ${DTC} ${dtc_include} -I dts ) ; then 118 return 119 fi 120 121 echo "" >&2 122 echo "Possible hints to resolve the above error:" >&2 123 echo " (hints might not fix the problem)" >&2 124 125 hint_given=0 126 127 if [ "${ARCH}" = "" ] ; then 128 hint_given=1 129 echo "" >&2 130 echo " shell variable \$ARCH not set" >&2 131 fi 132 133 dtx_arch=`echo "/${dtx}" | sed -e 's|.*/arch/||' -e 's|/.*||'` 134 135 if [ "${dtx_arch}" != "" -a "${dtx_arch}" != "${ARCH}" ] ; then 136 hint_given=1 137 echo "" >&2 138 echo " architecture ${dtx_arch} is in file path," >&2 139 echo " but does not match shell variable \$ARCH" >&2 140 echo " >>\$ARCH<< is: >>${ARCH}<<" >&2 141 fi 142 143 if [ ! -d ${srctree}/arch/${ARCH} ] ; then 144 hint_given=1 145 echo "" >&2 146 echo " ${srctree}/arch/${ARCH}/ does not exist" >&2 147 echo " Is \$ARCH='${ARCH}' correct?" >&2 148 echo " Possible fix: use '-s' option" >&2 149 150 git_root=`git rev-parse --show-toplevel 2>/dev/null` 151 if [ -d ${git_root}/arch/ ] ; then 152 echo " Possible fix: use '-S' option" >&2 153 fi 154 fi 155 156 if [ $hint_given = 0 ] ; then 157 echo "" >&2 158 echo " No hints available." >&2 159 fi 160 161 echo "" >&2 162 163 exit 3 164 165 else 166 echo "" >&2 167 echo "ERROR: ${dtx} does not exist or is not readable" >&2 168 echo "" >&2 169 exit 2 170 fi 171 172} 173 174 175# ----- start of script 176 177annotate="" 178cmd_diff=0 179diff_flags="-u" 180dtx_file_1="" 181dtx_file_2="" 182dtc_sort="-s" 183help=0 184srctree="" 185 186 187while [ $# -gt 0 ] ; do 188 189 case $1 in 190 191 -f ) 192 diff_flags="--unified=999999" 193 shift 194 ;; 195 196 -h | -help | --help ) 197 help=1 198 shift 199 ;; 200 201 -s ) 202 srctree="$2" 203 shift 2 204 ;; 205 206 -S ) 207 git_root=`git rev-parse --show-toplevel 2>/dev/null` 208 srctree="${git_root}" 209 shift 210 ;; 211 212 -T | --annotate ) 213 if [ "${annotate}" = "" ] ; then 214 annotate="-T" 215 elif [ "${annotate}" = "-T" ] ; then 216 annotate="-T -T" 217 fi 218 shift 219 ;; 220 -u ) 221 dtc_sort="" 222 shift 223 ;; 224 225 *) 226 if [ "${dtx_file_1}" = "" ] ; then 227 dtx_file_1="$1" 228 elif [ "${dtx_file_2}" = "" ] ; then 229 dtx_file_2="$1" 230 else 231 echo "" >&2 232 echo "ERROR: Unexpected parameter: $1" >&2 233 echo "" >&2 234 exit 2 235 fi 236 shift 237 ;; 238 239 esac 240 241done 242 243if [ "${srctree}" = "" ] ; then 244 srctree="." 245fi 246 247if [ "${dtx_file_2}" != "" ]; then 248 cmd_diff=1 249fi 250 251if (( ${help} )) ; then 252 usage 253 exit 1 254fi 255 256# this must follow check for ${help} 257if [ "${dtx_file_1}" = "" ]; then 258 echo "" >&2 259 echo "ERROR: parameter DTx required" >&2 260 echo "" >&2 261 exit 2 262fi 263 264 265# ----- prefer dtc from linux kernel, allow fallback to dtc in $PATH 266 267if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then 268 __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}" 269elif [ "${KBUILD_OUTPUT}" = "" ] ; then 270 __KBUILD_OUTPUT="." 271else 272 __KBUILD_OUTPUT="${KBUILD_OUTPUT}" 273fi 274 275DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc" 276 277if [ ! -x ${DTC} ] ; then 278 __DTC="dtc" 279 if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then 280 make_command=' 281 make scripts' 282 else 283 make_command=' 284 Enable CONFIG_DTC in the kernel configuration 285 make scripts' 286 fi 287 if ( ! which ${__DTC} >/dev/null ) ; then 288 289 # use spaces instead of tabs in the error message 290 cat >&2 <<eod 291 292ERROR: unable to find a 'dtc' program 293 294 Preferred 'dtc' (built from Linux kernel source tree) was not found or 295 is not executable. 296 297 'dtc' is: ${DTC} 298 299 If it does not exist, create it from the root of the Linux source tree: 300${make_command} 301 302 If not at the root of the Linux kernel source tree -s SRCTREE or -S 303 may need to be specified to find 'dtc'. 304 305 If 'O=\${dir}' is specified in your Linux builds, this script requires 306 'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH 307 before running. 308 309 If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run 310 this script from the root of the Linux kernel source tree is required. 311 312 Fallback '${__DTC}' was also not in \${PATH} or is not executable. 313 314eod 315 exit 2 316 fi 317 DTC=${__DTC} 318fi 319 320 321# ----- cpp and dtc flags same as for linux source tree build of .dtb files, 322# plus directories of the dtx file(s) 323 324dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`" 325 326dtx_path_2_dtc_include="" 327if (( ${cmd_diff} )) ; then 328 dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`" 329fi 330 331cpp_flags="\ 332 -nostdinc \ 333 -I${srctree}/scripts/dtc/include-prefixes \ 334 -undef -D__DTS__" 335 336DTC="\ 337 ${DTC} \ 338 -i ${srctree}/scripts/dtc/include-prefixes \ 339 -O dts -qq -f ${dtc_sort} ${annotate} -o -" 340 341 342# ----- do the diff or decompile 343 344if (( ${cmd_diff} )) ; then 345 346 diff ${diff_flags} --label "${dtx_file_1}" --label "${dtx_file_2}" \ 347 <(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \ 348 <(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}") 349 350else 351 352 compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}" 353 354fi 355