1 #! /bin/bash 2 # SPDX-License-Identifier: GPL-2.0-only 3 4 # Copyright (C) 2015 Frank Rowand 5 # 6 7 8 usage() { 9 10 # use spaces instead of tabs in the usage message 11 cat >&2 <<eod 12 13 Usage: 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 --color synonym for -c (requires diff with --color support) 24 -c enable colored output 25 -f print full dts in diff (--unified=99999) 26 -h synonym for --help 27 -help synonym for --help 28 --help print this message and exit 29 -s SRCTREE linux kernel source tree is at path SRCTREE 30 (default is current directory) 31 -S linux kernel source tree is at root of current git repo 32 -T annotate output .dts with input source file and line 33 (-T -T for more details) 34 -u unsorted, do not sort DTx 35 36 37 Each DTx is processed by the dtc compiler to produce a sorted dts source 38 file. If DTx is a dts source file then it is pre-processed in the same 39 manner as done for the compile of the dts source file in the Linux kernel 40 build system ('#include' and '/include/' directives are processed). 41 42 If two DTx are provided, the resulting dts source files are diffed. 43 44 If DTx is a directory, it is treated as a DT subtree, such as 45 /proc/device-tree. 46 47 If DTx contains the binary blob magic value in the first four bytes, 48 it is treated as a binary blob (aka .dtb or FDT). 49 50 Otherwise DTx is treated as a dts source file (aka .dts). 51 52 If this script is not run from the root of the linux source tree, 53 and DTx utilizes '#include' or '/include/' then the path of the 54 linux source tree can be provided by '-s SRCTREE' or '-S' so that 55 include paths will be set properly. 56 57 The shell variable \${ARCH} must provide the architecture containing 58 the dts source file for include paths to be set properly for '#include' 59 or '/include/' to be processed. 60 61 If DTx_1 and DTx_2 are in different architectures, then this script 62 may not work since \${ARCH} is part of the include path. The following 63 workaround can be used: 64 65 `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts 66 `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts 67 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 68 rm tmp_dtx_1.dts tmp_dtx_2.dts 69 70 If DTx_1 and DTx_2 are in different directories, then this script will 71 add the path of DTx_1 and DTx_2 to the include paths. If DTx_2 includes 72 a local file that exists in both the path of DTx_1 and DTx_2 then the 73 file in the path of DTx_1 will incorrectly be included. Possible 74 workaround: 75 76 `basename $0` DTx_1 >tmp_dtx_1.dts 77 `basename $0` DTx_2 >tmp_dtx_2.dts 78 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 79 rm tmp_dtx_1.dts tmp_dtx_2.dts 80 81 eod 82 } 83 84 85 compile_to_dts() { 86 87 dtx="$1" 88 dtc_include="$2" 89 90 if [ -d "${dtx}" ] ; then 91 92 # ----- input is file tree 93 94 if ( ! ${DTC} -I fs ${dtx} ) ; then 95 exit 3 96 fi 97 98 elif [ -f "${dtx}" ] && [ -r "${dtx}" ] ; then 99 100 magic=`hexdump -n 4 -e '/1 "%02x"' ${dtx}` 101 if [ "${magic}" = "d00dfeed" ] ; then 102 103 # ----- input is FDT (binary blob) 104 105 if ( ! ${DTC} -I dtb ${dtx} ) ; then 106 exit 3 107 fi 108 109 return 110 111 fi 112 113 # ----- input is DTS (source) 114 115 if ( cpp ${cpp_flags} -x assembler-with-cpp ${dtx} \ 116 | ${DTC} ${dtc_include} -I dts ) ; then 117 return 118 fi 119 120 echo "" >&2 121 echo "Possible hints to resolve the above error:" >&2 122 echo " (hints might not fix the problem)" >&2 123 124 hint_given=0 125 126 if [ "${ARCH}" = "" ] ; then 127 hint_given=1 128 echo "" >&2 129 echo " shell variable \$ARCH not set" >&2 130 fi 131 132 dtx_arch=`echo "/${dtx}" | sed -e 's|.*/arch/||' -e 's|/.*||'` 133 134 if [ "${dtx_arch}" != "" -a "${dtx_arch}" != "${ARCH}" ] ; then 135 hint_given=1 136 echo "" >&2 137 echo " architecture ${dtx_arch} is in file path," >&2 138 echo " but does not match shell variable \$ARCH" >&2 139 echo " >>\$ARCH<< is: >>${ARCH}<<" >&2 140 fi 141 142 if [ ! -d ${srctree}/arch/${ARCH} ] ; then 143 hint_given=1 144 echo "" >&2 145 echo " ${srctree}/arch/${ARCH}/ does not exist" >&2 146 echo " Is \$ARCH='${ARCH}' correct?" >&2 147 echo " Possible fix: use '-s' option" >&2 148 149 git_root=`git rev-parse --show-toplevel 2>/dev/null` 150 if [ -d ${git_root}/arch/ ] ; then 151 echo " Possible fix: use '-S' option" >&2 152 fi 153 fi 154 155 if [ $hint_given = 0 ] ; then 156 echo "" >&2 157 echo " No hints available." >&2 158 fi 159 160 echo "" >&2 161 162 exit 3 163 164 else 165 echo "" >&2 166 echo "ERROR: ${dtx} does not exist or is not readable" >&2 167 echo "" >&2 168 exit 2 169 fi 170 171 } 172 173 174 # ----- start of script 175 176 annotate="" 177 cmd_diff=0 178 diff_flags="-u" 179 diff_color="" 180 dtx_file_1="" 181 dtx_file_2="" 182 dtc_sort="-s" 183 help=0 184 srctree="" 185 186 187 while [ $# -gt 0 ] ; do 188 189 case $1 in 190 191 -c | --color ) 192 if diff --color /dev/null /dev/null 2>/dev/null ; then 193 diff_color="--color=always" 194 fi 195 shift 196 ;; 197 198 -f ) 199 diff_flags="--unified=999999" 200 shift 201 ;; 202 203 -h | -help | --help ) 204 help=1 205 shift 206 ;; 207 208 -s ) 209 srctree="$2" 210 shift 2 211 ;; 212 213 -S ) 214 git_root=`git rev-parse --show-toplevel 2>/dev/null` 215 srctree="${git_root}" 216 shift 217 ;; 218 219 -T | --annotate ) 220 if [ "${annotate}" = "" ] ; then 221 annotate="-T" 222 elif [ "${annotate}" = "-T" ] ; then 223 annotate="-T -T" 224 fi 225 shift 226 ;; 227 -u ) 228 dtc_sort="" 229 shift 230 ;; 231 232 *) 233 if [ "${dtx_file_1}" = "" ] ; then 234 dtx_file_1="$1" 235 elif [ "${dtx_file_2}" = "" ] ; then 236 dtx_file_2="$1" 237 else 238 echo "" >&2 239 echo "ERROR: Unexpected parameter: $1" >&2 240 echo "" >&2 241 exit 2 242 fi 243 shift 244 ;; 245 246 esac 247 248 done 249 250 if [ "${srctree}" = "" ] ; then 251 srctree="." 252 fi 253 254 if [ "${dtx_file_2}" != "" ]; then 255 cmd_diff=1 256 fi 257 258 if (( ${help} )) ; then 259 usage 260 exit 1 261 fi 262 263 # this must follow check for ${help} 264 if [ "${dtx_file_1}" = "" ]; then 265 echo "" >&2 266 echo "ERROR: parameter DTx required" >&2 267 echo "" >&2 268 exit 2 269 fi 270 271 272 # ----- prefer dtc from linux kernel, allow fallback to dtc in $PATH 273 274 if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then 275 __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}" 276 elif [ "${KBUILD_OUTPUT}" = "" ] ; then 277 __KBUILD_OUTPUT="." 278 else 279 __KBUILD_OUTPUT="${KBUILD_OUTPUT}" 280 fi 281 282 DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc" 283 284 if [ ! -x ${DTC} ] ; then 285 __DTC="dtc" 286 if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then 287 make_command=' 288 make scripts' 289 else 290 make_command=' 291 Enable CONFIG_DTC in the kernel configuration 292 make scripts' 293 fi 294 if ( ! which ${__DTC} >/dev/null ) ; then 295 296 # use spaces instead of tabs in the error message 297 cat >&2 <<eod 298 299 ERROR: unable to find a 'dtc' program 300 301 Preferred 'dtc' (built from Linux kernel source tree) was not found or 302 is not executable. 303 304 'dtc' is: ${DTC} 305 306 If it does not exist, create it from the root of the Linux source tree: 307 ${make_command} 308 309 If not at the root of the Linux kernel source tree -s SRCTREE or -S 310 may need to be specified to find 'dtc'. 311 312 If 'O=\${dir}' is specified in your Linux builds, this script requires 313 'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH 314 before running. 315 316 If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run 317 this script from the root of the Linux kernel source tree is required. 318 319 Fallback '${__DTC}' was also not in \${PATH} or is not executable. 320 321 eod 322 exit 2 323 fi 324 DTC=${__DTC} 325 fi 326 327 328 # ----- cpp and dtc flags same as for linux source tree build of .dtb files, 329 # plus directories of the dtx file(s) 330 331 dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`" 332 333 dtx_path_2_dtc_include="" 334 if (( ${cmd_diff} )) ; then 335 dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`" 336 fi 337 338 cpp_flags="\ 339 -nostdinc \ 340 -I${srctree}/scripts/dtc/include-prefixes \ 341 -undef -D__DTS__" 342 343 DTC="\ 344 ${DTC} \ 345 -i ${srctree}/scripts/dtc/include-prefixes \ 346 -O dts -qq -f ${dtc_sort} ${annotate} -o -" 347 348 349 # ----- do the diff or decompile 350 351 if (( ${cmd_diff} )) ; then 352 353 diff ${diff_flags} ${diff_color} --label "${dtx_file_1}" --label "${dtx_file_2}" \ 354 <(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \ 355 <(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}") 356 357 else 358 359 compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}" 360 361 fi 362