doc: describe the md command
Provide a man-page for the md command.
Signed-off-by: Simon Glass <sjg@chromium.org>
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+.. SPDX-License-Identifier: GPL-2.0+:
+
+md command
+==========
+
+Synopis
+-------
+
+::
+
+ md <address>[<data_size>] [<length>]
+
+Description
+-----------
+
+The md command is used to dump the contents of memory. It uses a standard
+format that includes the address, hex data and ASCII display. It supports
+various data sizes and uses the endianness of the target.
+
+The specified data_size and length become the defaults for future memory
+commands commands.
+
+address
+ start address to display
+
+data_size
+ size of each value to display (defaults to .l):
+
+ ========= ===================
+ data_size Output size
+ ========= ===================
+ .b byte
+ .w word (16 bits)
+ .l long (32 bits)
+ .q quadword (64 bits)
+ ========= ===================
+
+length
+ number of values to dump. Defaults to 40 (0d64). Note that this is not
+ the same as the number of bytes, unless .b is used.
+
+
+Example
+-------
+
+::
+
+ => md 10000
+ 00010000: 00010000 00000000 f0f30f00 00005596 .............U..
+ 00010010: 10011010 00000000 10011010 00000000 ................
+ 00010020: 10011050 00000000 b96d4cd8 00007fff P........Lm.....
+ 00010030: 00000000 00000000 f0f30f18 00005596 .............U..
+ 00010040: 10011040 00000000 10011040 00000000 @.......@.......
+ 00010050: b96d4cd8 00007fff 10011020 00000000 .Lm..... .......
+ 00010060: 00000003 000000c3 00000000 00000000 ................
+ 00010070: 00000000 00000000 f0e892f3 00005596 .............U..
+ 00010080: 00000000 000000a1 00000000 00000000 ................
+ 00010090: 00000000 00000000 f0e38aa6 00005596 .............U..
+ 000100a0: 00000000 000000a6 00000022 00000000 ........".......
+ 000100b0: 00000001 00000000 f0e38aa1 00005596 .............U..
+ 000100c0: 00000000 000000be 00000000 00000000 ................
+ 000100d0: 00000000 00000000 00000000 00000000 ................
+ 000100e0: 00000000 00000000 00000000 00000000 ................
+ 000100f0: 00000000 00000000 00000000 00000000 ................
+ => md.b 10000
+ 00010000: 00 00 01 00 00 00 00 00 00 0f f3 f0 96 55 00 00 .............U..
+ 00010010: 10 10 01 10 00 00 00 00 10 10 01 10 00 00 00 00 ................
+ 00010020: 50 10 01 10 00 00 00 00 d8 4c 6d b9 ff 7f 00 00 P........Lm.....
+ 00010030: 00 00 00 00 00 00 00 00 18 0f f3 f0 96 55 00 00 .............U..
+ => md.b 10000 10
+ 00010000: 00 00 01 00 00 00 00 00 00 0f f3 f0 96 55 00 00 .............U..
+ =>
+ 00010010: 10 10 01 10 00 00 00 00 10 10 01 10 00 00 00 00 ................
+ =>
+ 00010020: 50 10 01 10 00 00 00 00 d8 4c 6d b9 ff 7f 00 00 P........Lm.....
+ =>
+ => md.q 10000
+ 00010000: 0000000000010000 00005596f0f30f00 .............U..
+ 00010010: 0000000010011010 0000000010011010 ................
+ 00010020: 0000000010011050 00007fffb96d4cd8 P........Lm.....
+ 00010030: 0000000000000000 00005596f0f30f18 .............U..
+ 00010040: 0000000010011040 0000000010011040 @.......@.......
+ 00010050: 00007fffb96d4cd8 0000000010011020 .Lm..... .......
+ 00010060: 000000c300000003 0000000000000000 ................
+ 00010070: 0000000000000000 00005596f0e892f3 .............U..
+
+The empty commands cause a 'repeat', so that md shows the next available data
+in the same format as before.
+
+
+Return value
+------------
+
+The return value $? is always 0 (true).
+
+