scripts/dtc/dtx_diff

   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        -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
  34 Each DTx is processed by the dtc compiler to produce a sorted dts source
  35 file.  If DTx is a dts source file then it is pre-processed in the same
  36 manner as done for the compile of the dts source file in the Linux kernel
  37 build system ('#include' and '/include/' directives are processed).
  38
  39 If two DTx are provided, the resulting dts source files are diffed.
  40
  41 If DTx is a directory, it is treated as a DT subtree, such as
  42   /proc/device-tree.
  43
  44 If 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
  47 Otherwise 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
  82 eod
  83 }
  84
  85
  86 compile_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
 177 annotate=""
 178 cmd_diff=0
 179 diff_flags="-u"
 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         -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: $1"              >&2
 233                         echo ""                                             >&2
 234                         exit 2
 235                 fi
 236                 shift
 237                 ;;
 238
 239         esac
 240
 241 done
 242
 243 if [ "${srctree}" = "" ] ; then
 244         srctree="."
 245 fi
 246
 247 if [ "${dtx_file_2}" != "" ]; then
 248         cmd_diff=1
 249 fi
 250
 251 if (( ${help} )) ; then
 252         usage
 253         exit 1
 254 fi
 255
 256 # this must follow check for ${help}
 257 if [ "${dtx_file_1}" = "" ]; then
 258         echo ""                                                             >&2
 259         echo "ERROR: parameter DTx required"                                >&2
 260         echo ""                                                             >&2
 261         exit 2
 262 fi
 263
 264
 265 # -----  prefer dtc from linux kernel, allow fallback to dtc in $PATH
 266
 267 if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then
 268         __KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}"
 269 elif [ "${KBUILD_OUTPUT}" = "" ] ; then
 270         __KBUILD_OUTPUT="."
 271 else
 272         __KBUILD_OUTPUT="${KBUILD_OUTPUT}"
 273 fi
 274
 275 DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc"
 276
 277 if [ ! -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
 292 ERROR: 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
 314 eod
 315                 exit 2
 316         fi
 317         DTC=${__DTC}
 318 fi
 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
 324 dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`"
 325
 326 dtx_path_2_dtc_include=""
 327 if (( ${cmd_diff} )) ; then
 328         dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`"
 329 fi
 330
 331 cpp_flags="\
 332         -nostdinc                                  \
 333         -I${srctree}/scripts/dtc/include-prefixes  \
 334         -undef -D__DTS__"
 335
 336 DTC="\
 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
 344 if (( ${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}" "${dtx_path_2_dtc_include}")
 349
 350 else
 351
 352         compile_to_dts "${dtx_file_1}" "${dtx_path_1_dtc_include}"
 353
 354 fi