summaryrefslogtreecommitdiff
path: root/scripts/dtc/dtx_diff
blob: f9a3d8d23c644a536ce0c9aaeed2c04b580af2f4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
#! /bin/bash

# Copyright (C) 2015 Frank Rowand
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.


usage() {

	# use spaces instead of tabs in the usage message
	cat >&2 <<eod

Usage:

   `basename $0` DTx
        decompile DTx

   `basename $0` DTx_1 DTx_2
        diff DTx_1 and DTx_2


       -f           print full dts in diff (--unified=99999)
       -h           synonym for --help
       -help        synonym for --help
      --help        print this message and exit
       -s SRCTREE   linux kernel source tree is at path SRCTREE
                        (default is current directory)
       -S           linux kernel source tree is at root of current git repo
       -u           unsorted, do not sort DTx


Each DTx is processed by the dtc compiler to produce a sorted dts source
file.  If DTx is a dts source file then it is pre-processed in the same
manner as done for the compile of the dts source file in the Linux kernel
build system ('#include' and '/include/' directives are processed).

If two DTx are provided, the resulting dts source files are diffed.

If DTx is a directory, it is treated as a DT subtree, such as
  /proc/device-tree.

If DTx contains the binary blob magic value in the first four bytes,
  it is treated as a binary blob (aka .dtb or FDT).

Otherwise DTx is treated as a dts source file (aka .dts).

   If this script is not run from the root of the linux source tree,
   and DTx utilizes '#include' or '/include/' then the path of the
   linux source tree can be provided by '-s SRCTREE' or '-S' so that
   include paths will be set properly.

   The shell variable \${ARCH} must provide the architecture containing
   the dts source file for include paths to be set properly for '#include'
   or '/include/' to be processed.

   If DTx_1 and DTx_2 are in different architectures, then this script
   may not work since \${ARCH} is part of the include path.  Two possible
   workarounds:

      `basename $0` \\
          <(ARCH=arch_of_dtx_1 `basename $0` DTx_1) \\
          <(ARCH=arch_of_dtx_2 `basename $0` DTx_2)

      `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts
      `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts
      `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts
      rm tmp_dtx_1.dts tmp_dtx_2.dts

   If DTx_1 and DTx_2 are in different directories, then this script will
   add the path of DTx_1 and DTx_2 to the include paths.  If DTx_2 includes
   a local file that exists in both the path of DTx_1 and DTx_2 then the
   file in the path of DTx_1 will incorrectly be included.  Possible
   workaround:

      `basename $0` DTx_1 >tmp_dtx_1.dts
      `basename $0` DTx_2 >tmp_dtx_2.dts
      `basename $0` tmp_dtx_1.dts tmp_dtx_2.dts
      rm tmp_dtx_1.dts tmp_dtx_2.dts

eod
}


compile_to_dts() {

	dtx="$1"

	if [ -d "${dtx}" ] ; then

		# -----  input is file tree

		if ( ! ${DTC} -I fs ${dtx} ) ; then
			exit 3
		fi

	elif [ -f "${dtx}" ] && [ -r "${dtx}" ] ; then

		magic=`hexdump -n 4 -e '/1 "%02x"' ${dtx}`
		if [ "${magic}" = "d00dfeed" ] ; then

			# -----  input is FDT (binary blob)

			if ( ! ${DTC} -I dtb ${dtx} ) ; then
				exit 3
			fi

			return

		fi

		# -----  input is DTS (source)

		if ( cpp ${cpp_flags} -x assembler-with-cpp ${dtx} \
			| ${DTC} -I dts ) ; then
			return
		fi

		echo ""                                                      >&2
		echo "Possible hints to resolve the above error:"            >&2
		echo "  (hints might not fix the problem)"                   >&2

		hint_given=0

		if [ "${ARCH}" = "" ] ; then
			hint_given=1
			echo ""                                              >&2
			echo "  shell variable \$ARCH not set"               >&2
		fi

		dtx_arch=`echo "/${dtx}" | sed -e 's|.*/arch/||' -e 's|/.*||'`

		if [ "${dtx_arch}" != ""  -a "${dtx_arch}" != "${ARCH}" ] ; then
			hint_given=1
			echo ""                                              >&2
			echo "  architecture ${dtx_arch} is in file path,"   >&2
			echo "  but does not match shell variable \$ARCH"    >&2
			echo "  >>\$ARCH<< is: >>${ARCH}<<"                  >&2
		fi

		if [ ! -d ${srctree}/arch/${ARCH} ] ; then
			hint_given=1
			echo ""                                              >&2
			echo "  ${srctree}/arch/${ARCH}/ does not exist"     >&2
			echo "  Is \$ARCH='${ARCH}' correct?"                >&2
			echo "  Possible fix: use '-s' option"               >&2

			git_root=`git rev-parse --show-toplevel 2>/dev/null`
			if [ -d ${git_root}/arch/ ] ; then
				echo "  Possible fix: use '-S' option"       >&2
			fi
		fi

		if [ $hint_given = 0 ] ; then
			echo ""                                              >&2
			echo "  No hints available."                         >&2
		fi

		echo ""                                                      >&2

		exit 3

	else
		echo ""                                                     >&2
		echo "ERROR: ${dtx} does not exist or is not readable"      >&2
		echo ""                                                     >&2
		exit 2
	fi

}


# -----  start of script

cmd_diff=0
diff_flags="-u"
dtx_file_1=""
dtx_file_2=""
dtc_sort="-s"
help=0
srctree=""


while [ $# -gt 0 ] ; do

	case $1 in

	-f )
		diff_flags="--unified=999999"
		shift
		;;

	-h | -help | --help )
		help=1
		shift
		;;

	-s )
		srctree="$2"
		shift 2
		;;

	-S )
		git_root=`git rev-parse --show-toplevel 2>/dev/null`
		srctree="${git_root}"
		shift
		;;

	-u )
		dtc_sort=""
		shift
		;;

	*)
		if [ "${dtx_file_1}"  = "" ] ; then
			dtx_file_1="$1"
		elif [ "${dtx_file_2}" = "" ] ; then
			dtx_file_2="$1"
		else
			echo ""                                             >&2
			echo "ERROR: Unexpected parameter: $1"              >&2
			echo ""                                             >&2
			exit 2
		fi
		shift
		;;

	esac

done

if [ "${srctree}" = "" ] ; then
	srctree="."
fi

if [ "${dtx_file_2}" != "" ]; then
	cmd_diff=1
fi

if (( ${help} )) ; then
	usage
	exit 1
fi

# this must follow check for ${help}
if [ "${dtx_file_1}" = "" ]; then
	echo ""                                                             >&2
	echo "ERROR: parameter DTx required"                                >&2
	echo ""                                                             >&2
	exit 2
fi


# -----  prefer dtc from linux kernel, allow fallback to dtc in $PATH

if [ "${KBUILD_OUTPUT:0:2}" = ".." ] ; then
	__KBUILD_OUTPUT="${srctree}/${KBUILD_OUTPUT}"
elif [ "${KBUILD_OUTPUT}" = "" ] ; then
	__KBUILD_OUTPUT="."
else
	__KBUILD_OUTPUT="${KBUILD_OUTPUT}"
fi

DTC="${__KBUILD_OUTPUT}/scripts/dtc/dtc"

if [ ! -x ${DTC} ] ; then
	__DTC="dtc"
	if grep -q "^CONFIG_DTC=y" ${__KBUILD_OUTPUT}/.config 2>/dev/null; then
		make_command='
         make scripts'
	else
		make_command='
         Enable CONFIG_DTC in the kernel configuration
         make scripts'
	fi
	if ( ! which ${__DTC} >/dev/null ) ; then

		# use spaces instead of tabs in the error message
		cat >&2 <<eod

ERROR: unable to find a 'dtc' program

   Preferred 'dtc' (built from Linux kernel source tree) was not found or
   is not executable.

      'dtc' is: ${DTC}

      If it does not exist, create it from the root of the Linux source tree:
${make_command}

      If not at the root of the Linux kernel source tree -s SRCTREE or -S
      may need to be specified to find 'dtc'.

      If 'O=\${dir}' is specified in your Linux builds, this script requires
      'export KBUILD_OUTPUT=\${dir}' or add \${dir}/scripts/dtc to \$PATH
      before running.

      If \${KBUILD_OUTPUT} is a relative path, then '-s SRCDIR', -S, or run
      this script from the root of the Linux kernel source tree is required.

   Fallback '${__DTC}' was also not in \${PATH} or is not executable.

eod
		exit 2
	fi
	DTC=${__DTC}
fi


# -----  cpp and dtc flags same as for linux source tree build of .dtb files,
#        plus directories of the dtx file(s)

dtx_path_1_dtc_include="-i `dirname ${dtx_file_1}`"

dtx_path_2_dtc_include=""
if (( ${cmd_diff} )) ; then
	dtx_path_2_dtc_include="-i `dirname ${dtx_file_2}`"
fi

cpp_flags="\
	-nostdinc                                  \
	-I${srctree}/arch/${ARCH}/boot/dts         \
	-I${srctree}/scripts/dtc/include-prefixes  \
	-I${srctree}/drivers/of/testcase-data      \
	-undef -D__DTS__"

dtc_flags="\
	-i ${srctree}/arch/${ARCH}/boot/dts/ \
	-i ${srctree}/kernel/dts             \
	${dtx_path_1_dtc_include}            \
	${dtx_path_2_dtc_include}"

DTC="${DTC} ${dtc_flags} -O dts -qq -f ${dtc_sort} -o -"


# -----  do the diff or decompile

if (( ${cmd_diff} )) ; then

	diff ${diff_flags} --label "${dtx_file_1}" --label "${dtx_file_2}" \
		<(compile_to_dts "${dtx_file_1}") \
		<(compile_to_dts "${dtx_file_2}")

else

	compile_to_dts "${dtx_file_1}"

fi