scripts/dtc/dtx_diff

   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
  10 usage() {
  11
  12         # use spaces instead of tabs in the usage message
  13         cat >&2 <<eod
  14
  15 Usage:
  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       --annotate    synonym for -T
  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 dtx_file_1=""
 183 dtx_file_2=""
 184 dtc_sort="-s"
 185 help=0
 186 srctree=""
 187
 188
 189 while [ $# -gt 0 ] ; do
 190
 191         case $1 in
 192
 193         -f )
 194                 diff_flags="--unified=999999"
 195                 shift
 196                 ;;
 197
 198         -h | -help | --help )
 199                 help=1
 200                 shift
 201                 ;;
 202
 203         -s )
 204                 srctree="$2"
 205                 shift 2
 206                 ;;
 207
 208         -S )
 209                 git_root=`git rev-parse --show-toplevel 2>/dev/null`
 210                 srctree="${git_root}"
 211                 shift
 212                 ;;
 213
 214         -T | --annotate )
 215                 if [ "${annotate}"  = "" ] ; then
 216                         annotate="-T"
 217                 elif [ "${annotate}"  = "-T" ] ; then
 218                         annotate="-T -T"
 219                 fi
 220                 shift
 221                 ;;
 222         -u )
 223                 dtc_sort=""
 224                 shift
 225                 ;;
 226
 227         *)
 228                 if [ "${dtx_file_1}"  = "" ] ; then
 229                         dtx_file_1="$1"
 230                 elif [ "${dtx_file_2}" = "" ] ; then
 231                         dtx_file_2="$1"
 232                 else
 233                         echo ""                                             >&2
 234                         echo "ERROR: Unexpected parameter: $1"              >&2
 235                         echo ""                                             >&2
 236                         exit 2
 237                 fi
 238                 shift
 239                 ;;
 240
 241         esac
 242
 243 done
 244
 245 if [ "${srctree}" = "" ] ; then
 246         srctree="."
 247 fi
 248
 249 if [ "${dtx_file_2}" != "" ]; then
 250         cmd_diff=1
 251 fi
 252
 253 if (( ${help} )) ; then
 254         usage
 255         exit 1
 256 fi
 257
 258 # this must follow check for ${help}
 259 if [ "${dtx_file_1}" = "" ]; then
 260         echo ""                                                             >&2
 261         echo "ERROR: parameter DTx required"                                >&2
 262         echo ""                                                             >&2
 263         exit 2
 264 fi
 265
 266
 267 # -----  prefer dtc from linux kernel, allow fallback to dtc in $PATH
 268
 269 if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then
 270         __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}"
 271 elif [ "${KBUILD_OUTPUT}" = "" ] ; then
 272         __KBUILD_OUTPUT="."
 273 else
 274         __KBUILD_OUTPUT="${KBUILD_OUTPUT}"
 275 fi
 276
 277 DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc"
 278
 279 if [ ! -x ${DTC} ] ; then
 280         __DTC="dtc"
 281         if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then
 282                 make_command='
 283          make scripts'
 284         else
 285                 make_command='
 286          Enable CONFIG_DTC in the kernel configuration
 287          make scripts'
 288         fi
 289         if ( ! which ${__DTC} >/dev/null ) ; then
 290
 291                 # use spaces instead of tabs in the error message
 292                 cat >&2 <<eod
 293
 294 ERROR: unable to find a 'dtc' program
 295
 296    Preferred 'dtc' (built from Linux kernel source tree) was not found or
 297    is not executable.
 298
 299       'dtc' is: ${DTC}
 300
 301       If it does not exist, create it from the root of the Linux source tree:
 302 ${make_command}
 303
 304       If not at the root of the Linux kernel source tree -s SRCTREE or -S
 305       may need to be specified to find 'dtc'.
 306
 307       If 'O=\${dir}' is specified in your Linux builds, this script requires
 308       'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH
 309       before running.
 310
 311       If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run
 312       this script from the root of the Linux kernel source tree is required.
 313
 314    Fallback '${__DTC}' was also not in \${PATH} or is not executable.
 315
 316 eod
 317                 exit 2
 318         fi
 319         DTC=${__DTC}
 320 fi
 321
 322
 323 # -----  cpp and dtc flags same as for linux source tree build of .dtb files,
 324 #        plus directories of the dtx file(s)
 325
 326 dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`"
 327
 328 dtx_path_2_dtc_include=""
 329 if (( ${cmd_diff} )) ; then
 330         dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`"
 331 fi
 332
 333 cpp_flags="\
 334         -nostdinc                                  \
 335         -I${srctree}/scripts/dtc/include-prefixes  \
 336         -undef -D__DTS__"
 337
 338 DTC="\
 339         ${DTC}                                     \
 340         -i ${srctree}/scripts/dtc/include-prefixes \
 341         -O dts -qq -f ${dtc_sort} ${annotate} -o -"
 342
 343
 344 # -----  do the diff or decompile
 345
 346 if (( ${cmd_diff} )) ; then
 347
 348         diff ${diff_flags} --label "${dtx_file_1}" --label "${dtx_file_2}" \
 349                 <(compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}") \
 350                 <(compile_to_dts "${dtx_file_2}" "${dtx_path_2_dtc_include}")
 351
 352 else
 353
 354         compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}"
 355
 356 fi