1#! /bin/bash 2 3# Copyright (C) 2015 Frank Rowand 4# 5# This program is free software; you can redistribute it and/or modify 6# it under the terms of the GNU General Public License as published by 7# the Free Software Foundation; version 2 of the License. 8 9 10usage() { 11 12 # use spaces instead of tabs in the usage message 13 cat >&2 <<eod 14 15Usage: 16 17 `basename $0` DTx 18 decompile DTx 19 20 `basename $0` DTx_1 DTx_2 21 diff DTx_1 and DTx_2 22 23 24 -f print full dts in diff (--unified=99999) 25 -h synonym for --help 26 -help synonym for --help 27 --help print this message and exit 28 -s SRCTREE linux kernel source tree is at path SRCTREE 29 (default is current directory) 30 -S linux kernel source tree is at root of current git repo 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 177cmd_diff=0 178diff_flags="-u" 179dtx_file_1="" 180dtx_file_2="" 181dtc_sort="-s" 182help=0 183srctree="" 184 185 186while [ $# -gt 0 ] ; do 187 188 case $1 in 189 190 -f ) 191 diff_flags="--unified=999999" 192 shift 193 ;; 194 195 -h | -help | --help ) 196 help=1 197 shift 198 ;; 199 200 -s ) 201 srctree="$2" 202 shift 2 203 ;; 204 205 -S ) 206 git_root=`git rev-parse --show-toplevel 2>/dev/null` 207 srctree="${git_root}" 208 shift 209 ;; 210 211 -u ) 212 dtc_sort="" 213 shift 214 ;; 215 216 *) 217 if [ "${dtx_file_1}" = "" ] ; then 218 dtx_file_1="$1" 219 elif [ "${dtx_file_2}" = "" ] ; then 220 dtx_file_2="$1" 221 else 222 echo "" >&2 223 echo "ERROR: Unexpected parameter: $1" >&2 224 echo "" >&2 225 exit 2 226 fi 227 shift 228 ;; 229 230 esac 231 232done 233 234if [ "${srctree}" = "" ] ; then 235 srctree="." 236fi 237 238if [ "${dtx_file_2}" != "" ]; then 239 cmd_diff=1 240fi 241 242if (( ${help} )) ; then 243 usage 244 exit 1 245fi 246 247# this must follow check for ${help} 248if [ "${dtx_file_1}" = "" ]; then 249 echo "" >&2 250 echo "ERROR: parameter DTx required" >&2 251 echo "" >&2 252 exit 2 253fi 254 255 256# ----- prefer dtc from linux kernel, allow fallback to dtc in $PATH 257 258if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then 259 __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}" 260elif [ "${KBUILD_OUTPUT}" = "" ] ; then 261 __KBUILD_OUTPUT="." 262else 263 __KBUILD_OUTPUT="${KBUILD_OUTPUT}" 264fi 265 266DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc" 267 268if [ ! -x ${DTC} ] ; then 269 __DTC="dtc" 270 if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then 271 make_command=' 272 make scripts' 273 else 274 make_command=' 275 Enable CONFIG_DTC in the kernel configuration 276 make scripts' 277 fi 278 if ( ! which ${__DTC} >/dev/null ) ; then 279 280 # use spaces instead of tabs in the error message 281 cat >&2 <<eod 282 283ERROR: unable to find a 'dtc' program 284 285 Preferred 'dtc' (built from Linux kernel source tree) was not found or 286 is not executable. 287 288 'dtc' is: ${DTC} 289 290 If it does not exist, create it from the root of the Linux source tree: 291${make_command} 292 293 If not at the root of the Linux kernel source tree -s SRCTREE or -S 294 may need to be specified to find 'dtc'. 295 296 If 'O=\${dir}' is specified in your Linux builds, this script requires 297 'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH 298 before running. 299 300 If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run 301 this script from the root of the Linux kernel source tree is required. 302 303 Fallback '${__DTC}' was also not in \${PATH} or is not executable. 304 305eod 306 exit 2 307 fi 308 DTC=${__DTC} 309fi 310 311 312# ----- cpp and dtc flags same as for linux source tree build of .dtb files, 313# plus directories of the dtx file(s) 314 315dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`" 316 317dtx_path_2_dtc_include="" 318if (( ${cmd_diff} )) ; then 319 dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`" 320fi 321 322cpp_flags="\ 323 -nostdinc \ 324 -I${srctree}/scripts/dtc/include-prefixes \ 325 -undef -D__DTS__" 326 327DTC="\ 328 ${DTC} \ 329 -i ${srctree}/scripts/dtc/include-prefixes \ 330 -O dts -qq -f ${dtc_sort} -o -" 331 332 333# ----- do the diff or decompile 334 335if (( ${cmd_diff} )) ; then 336 337 diff ${diff_flags} --label "${dtx_file_1}" --label "${dtx_file_2}" \ 338 <(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \ 339 <(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}") 340 341else 342 343 compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}" 344 345fi 346