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 (-T -T for more details) 33 -u unsorted, do not sort DTx 34 35 36 Each DTx is processed by the dtc compiler to produce a sorted dts source 37 file. If DTx is a dts source file then it is pre-processed in the same 38 manner as done for the compile of the dts source file in the Linux kernel 39 build system ('#include' and '/include/' directives are processed). 40 41 If two DTx are provided, the resulting dts source files are diffed. 42 43 If DTx is a directory, it is treated as a DT subtree, such as 44 /proc/device-tree. 45 46 If DTx contains the binary blob magic value in the first four bytes, 47 it is treated as a binary blob (aka .dtb or FDT). 48 49 Otherwise DTx is treated as a dts source file (aka .dts). 50 51 If this script is not run from the root of the linux source tree, 52 and DTx utilizes '#include' or '/include/' then the path of the 53 linux source tree can be provided by '-s SRCTREE' or '-S' so that 54 include paths will be set properly. 55 56 The shell variable \${ARCH} must provide the architecture containing 57 the dts source file for include paths to be set properly for '#include' 58 or '/include/' to be processed. 59 60 If DTx_1 and DTx_2 are in different architectures, then this script 61 may not work since \${ARCH} is part of the include path. Two possible 62 workarounds: 63 64 `basename $0` \\ 65 <(ARCH=arch_of_dtx_1 `basename $0` DTx_1) \\ 66 <(ARCH=arch_of_dtx_2 `basename $0` DTx_2) 67 68 `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts 69 `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts 70 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 71 rm tmp_dtx_1.dts tmp_dtx_2.dts 72 73 If DTx_1 and DTx_2 are in different directories, then this script will 74 add the path of DTx_1 and DTx_2 to the include paths. If DTx_2 includes 75 a local file that exists in both the path of DTx_1 and DTx_2 then the 76 file in the path of DTx_1 will incorrectly be included. Possible 77 workaround: 78 79 `basename $0` DTx_1 >tmp_dtx_1.dts 80 `basename $0` DTx_2 >tmp_dtx_2.dts 81 `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts 82 rm tmp_dtx_1.dts tmp_dtx_2.dts 83 84 eod 85 } 86 87 88 compile_to_dts() { 89 90 dtx="$1" 91 dtc_include="$2" 92 93 if [ -d "${dtx}" ] ; then 94 95 # ----- input is file tree 96 97 if ( ! ${DTC} -I fs ${dtx} ) ; then 98 exit 3 99 fi 100 101 elif [ -f "${dtx}" ] && [ -r "${dtx}" ] ; then 102 103 magic=`hexdump -n 4 -e '/1 "%02x"' ${dtx}` 104 if [ "${magic}" = "d00dfeed" ] ; then 105 106 # ----- input is FDT (binary blob) 107 108 if ( ! ${DTC} -I dtb ${dtx} ) ; then 109 exit 3 110 fi 111 112 return 113 114 fi 115 116 # ----- input is DTS (source) 117 118 if ( cpp ${cpp_flags} -x assembler-with-cpp ${dtx} \ 119 | ${DTC} ${dtc_include} -I dts ) ; then 120 return 121 fi 122 123 echo "" >&2 124 echo "Possible hints to resolve the above error:" >&2 125 echo " (hints might not fix the problem)" >&2 126 127 hint_given=0 128 129 if [ "${ARCH}" = "" ] ; then 130 hint_given=1 131 echo "" >&2 132 echo " shell variable \$ARCH not set" >&2 133 fi 134 135 dtx_arch=`echo "/${dtx}" | sed -e 's|.*/arch/||' -e 's|/.*||'` 136 137 if [ "${dtx_arch}" != "" -a "${dtx_arch}" != "${ARCH}" ] ; then 138 hint_given=1 139 echo "" >&2 140 echo " architecture ${dtx_arch} is in file path," >&2 141 echo " but does not match shell variable \$ARCH" >&2 142 echo " >>\$ARCH<< is: >>${ARCH}<<" >&2 143 fi 144 145 if [ ! -d ${srctree}/arch/${ARCH} ] ; then 146 hint_given=1 147 echo "" >&2 148 echo " ${srctree}/arch/${ARCH}/ does not exist" >&2 149 echo " Is \$ARCH='${ARCH}' correct?" >&2 150 echo " Possible fix: use '-s' option" >&2 151 152 git_root=`git rev-parse --show-toplevel 2>/dev/null` 153 if [ -d ${git_root}/arch/ ] ; then 154 echo " Possible fix: use '-S' option" >&2 155 fi 156 fi 157 158 if [ $hint_given = 0 ] ; then 159 echo "" >&2 160 echo " No hints available." >&2 161 fi 162 163 echo "" >&2 164 165 exit 3 166 167 else 168 echo "" >&2 169 echo "ERROR: ${dtx} does not exist or is not readable" >&2 170 echo "" >&2 171 exit 2 172 fi 173 174 } 175 176 177 # ----- start of script 178 179 annotate="" 180 cmd_diff=0 181 diff_flags="-u" 182 diff_color="" 183 dtx_file_1="" 184 dtx_file_2="" 185 dtc_sort="-s" 186 help=0 187 srctree="" 188 189 190 while [ $# -gt 0 ] ; do 191 192 case $1 in 193 194 -c | --color ) 195 if diff --color /dev/null /dev/null 2>/dev/null ; then 196 diff_color="--color=always" 197 fi 198 shift 199 ;; 200 201 -f ) 202 diff_flags="--unified=999999" 203 shift 204 ;; 205 206 -h | -help | --help ) 207 help=1 208 shift 209 ;; 210 211 -s ) 212 srctree="$2" 213 shift 2 214 ;; 215 216 -S ) 217 git_root=`git rev-parse --show-toplevel 2>/dev/null` 218 srctree="${git_root}" 219 shift 220 ;; 221 222 -T | --annotate ) 223 if [ "${annotate}" = "" ] ; then 224 annotate="-T" 225 elif [ "${annotate}" = "-T" ] ; then 226 annotate="-T -T" 227 fi 228 shift 229 ;; 230 -u ) 231 dtc_sort="" 232 shift 233 ;; 234 235 *) 236 if [ "${dtx_file_1}" = "" ] ; then 237 dtx_file_1="$1" 238 elif [ "${dtx_file_2}" = "" ] ; then 239 dtx_file_2="$1" 240 else 241 echo "" >&2 242 echo "ERROR: Unexpected parameter: $1" >&2 243 echo "" >&2 244 exit 2 245 fi 246 shift 247 ;; 248 249 esac 250 251 done 252 253 if [ "${srctree}" = "" ] ; then 254 srctree="." 255 fi 256 257 if [ "${dtx_file_2}" != "" ]; then 258 cmd_diff=1 259 fi 260 261 if (( ${help} )) ; then 262 usage 263 exit 1 264 fi 265 266 # this must follow check for ${help} 267 if [ "${dtx_file_1}" = "" ]; then 268 echo "" >&2 269 echo "ERROR: parameter DTx required" >&2 270 echo "" >&2 271 exit 2 272 fi 273 274 275 # ----- prefer dtc from linux kernel, allow fallback to dtc in $PATH 276 277 if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then 278 __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}" 279 elif [ "${KBUILD_OUTPUT}" = "" ] ; then 280 __KBUILD_OUTPUT="." 281 else 282 __KBUILD_OUTPUT="${KBUILD_OUTPUT}" 283 fi 284 285 DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc" 286 287 if [ ! -x ${DTC} ] ; then 288 __DTC="dtc" 289 if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then 290 make_command=' 291 make scripts' 292 else 293 make_command=' 294 Enable CONFIG_DTC in the kernel configuration 295 make scripts' 296 fi 297 if ( ! which ${__DTC} >/dev/null ) ; then 298 299 # use spaces instead of tabs in the error message 300 cat >&2 <<eod 301 302 ERROR: unable to find a 'dtc' program 303 304 Preferred 'dtc' (built from Linux kernel source tree) was not found or 305 is not executable. 306 307 'dtc' is: ${DTC} 308 309 If it does not exist, create it from the root of the Linux source tree: 310 ${make_command} 311 312 If not at the root of the Linux kernel source tree -s SRCTREE or -S 313 may need to be specified to find 'dtc'. 314 315 If 'O=\${dir}' is specified in your Linux builds, this script requires 316 'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH 317 before running. 318 319 If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run 320 this script from the root of the Linux kernel source tree is required. 321 322 Fallback '${__DTC}' was also not in \${PATH} or is not executable. 323 324 eod 325 exit 2 326 fi 327 DTC=${__DTC} 328 fi 329 330 331 # ----- cpp and dtc flags same as for linux source tree build of .dtb files, 332 # plus directories of the dtx file(s) 333 334 dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`" 335 336 dtx_path_2_dtc_include="" 337 if (( ${cmd_diff} )) ; then 338 dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`" 339 fi 340 341 cpp_flags="\ 342 -nostdinc \ 343 -I${srctree}/scripts/dtc/include-prefixes \ 344 -undef -D__DTS__" 345 346 DTC="\ 347 ${DTC} \ 348 -i ${srctree}/scripts/dtc/include-prefixes \ 349 -O dts -qq -f ${dtc_sort} ${annotate} -o -" 350 351 352 # ----- do the diff or decompile 353 354 if (( ${cmd_diff} )) ; then 355 356 diff ${diff_flags} ${diff_color} --label "${dtx_file_1}" --label "${dtx_file_2}" \ 357 <(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \ 358 <(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}") 359 360 else 361 362 compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}" 363 364 fi 365