blob: 241320d32891287550949c59a31cf1b04a5096e7 (
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
|
.. SPDX-License-Identifier: GPL-2.0+:
cmp command
===========
Synopsis
--------
::
cmp [.b, .w, .l, .q] addr1 addr2 count
Description
-----------
The cmp command is used to compare two memory areas. By default it works on
four byte tuples. By appending .b, .w, .l, .q the size of the tuples is
controlled:
cmp.b
compare 1 byte tuples
cmp.w
compare 2 byte tuples
cmp.l
compare 4 byte tuples
cmp.q
compare 8 byte tuples
The parameters are used as follows:
addr1
Address of the first memory area.
addr2
Address of the second memory area.
count
Number of bytes to compare (as hexadecimal number).
Example
-------
In the example below the strings "Hello world\n" and "Hello World\n" are written
to memory and then compared.
::
=> mm.b 0x1000000
01000000: 00 ? 48
01000001: 00 ? 65
01000002: 00 ? 6c
01000003: 00 ? 6c
01000004: 00 ? 6f
01000005: 00 ? 20
01000006: 00 ? 77
01000007: 00 ? 6f
01000008: 00 ? 72
01000009: 00 ? 6c
0100000a: 00 ? 64
0100000b: 00 ? 0d
0100000c: 00 ? => <INTERRUPT>
=> mm.b 0x101000
00101000: 00 ? 48
00101001: 00 ? 65
00101002: 00 ? 6c
00101003: 00 ? 6c
00101004: 00 ? 6f
00101005: 00 ? 20
00101006: 00 ? 57
00101007: 00 ? 6f
00101008: 00 ? 72
00101009: 00 ? 6c
0010100a: 00 ? 64
0010100b: 00 ? 0d
0010100c: 00 ? => <INTERRUPT>
=> cmp 0x1000000 0x101000 0xc
word at 0x01000004 (0x6f77206f) != word at 0x00101004 (0x6f57206f)
Total of 1 word(s) were the same
=> cmp.b 0x1000000 0x101000 0xc
byte at 0x01000006 (0x77) != byte at 0x00101006 (0x57)
Total of 6 byte(s) were the same
=> cmp.w 0x1000000 0x101000 0xc
halfword at 0x01000006 (0x6f77) != halfword at 0x00101006 (0x6f57)
Total of 3 halfword(s) were the same
=> cmp.l 0x1000000 0x101000 0xc
word at 0x01000004 (0x6f77206f) != word at 0x00101004 (0x6f57206f)
Total of 1 word(s) were the same
=> cmp.q 0x1000000 0x101000 0xc
double word at 0x01000000 (0x6f77206f6c6c6548) != double word at 0x00101000 (0x6f57206f6c6c6548)
Total of 0 double word(s) were the same
Configuration
-------------
The cmp command is only available if CONFIG_CMD_MEMORY=y. The cmp.q command is
only available if additionally CONFIG_MEM_SUPPORT_64BIT_DATA=y.
Return value
------------
The return value $? is true (0) if the compared memory areas are equal.
The reutrn value is false (1) if the compared memory areas differ.
|
