1 .. SPDX-License-Identifier: GPL-2.0 1 .. SPDX-License-Identifier: GPL-2.0
2 .. include:: <isonum.txt> 2 .. include:: <isonum.txt>
3 3
4 =============== 4 ===============
5 C2 port support 5 C2 port support
6 =============== 6 ===============
7 7
8 (C) Copyright 2007 Rodolfo Giometti <giometti@e 8 (C) Copyright 2007 Rodolfo Giometti <giometti@enneenne.com>
9 9
10 This program is free software; you can redistr 10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public L 11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version. 13 (at your option) any later version.
14 14
15 This program is distributed in the hope that i 15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the imp 16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PU 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details. 18 GNU General Public License for more details.
19 19
20 20
21 21
22 Overview 22 Overview
23 -------- 23 --------
24 24
25 This driver implements the support for Linux o 25 This driver implements the support for Linux of Silicon Labs (Silabs)
26 C2 Interface used for in-system programming of 26 C2 Interface used for in-system programming of micro controllers.
27 27
28 By using this driver you can reprogram the in- 28 By using this driver you can reprogram the in-system flash without EC2
29 or EC3 debug adapter. This solution is also us 29 or EC3 debug adapter. This solution is also useful in those systems
30 where the micro controller is connected via sp 30 where the micro controller is connected via special GPIOs pins.
31 31
32 References 32 References
33 ---------- 33 ----------
34 34
35 The C2 Interface main references are at (https 35 The C2 Interface main references are at (https://www.silabs.com)
36 Silicon Laboratories site], see: 36 Silicon Laboratories site], see:
37 37
38 - AN127: FLASH Programming via the C2 Interfac 38 - AN127: FLASH Programming via the C2 Interface at
39 https://www.silabs.com/Support Documents/Tec 39 https://www.silabs.com/Support Documents/TechnicalDocs/an127.pdf
40 40
41 - C2 Specification at 41 - C2 Specification at
42 https://www.silabs.com/pages/DownloadDoc.asp 42 https://www.silabs.com/pages/DownloadDoc.aspx?FILEURL=Support%20Documents/TechnicalDocs/an127.pdf&src=SearchResults
43 43
44 however it implements a two wire serial commun 44 however it implements a two wire serial communication protocol (bit
45 banging) designed to enable in-system programm 45 banging) designed to enable in-system programming, debugging, and
46 boundary-scan testing on low pin-count Silicon 46 boundary-scan testing on low pin-count Silicon Labs devices. Currently
47 this code supports only flash programming but 47 this code supports only flash programming but extensions are easy to
48 add. 48 add.
49 49
50 Using the driver 50 Using the driver
51 ---------------- 51 ----------------
52 52
53 Once the driver is loaded you can use sysfs su 53 Once the driver is loaded you can use sysfs support to get C2port's
54 info or read/write in-system flash:: 54 info or read/write in-system flash::
55 55
56 # ls /sys/class/c2port/c2port0/ 56 # ls /sys/class/c2port/c2port0/
57 access flash_block_size flash_er 57 access flash_block_size flash_erase rev_id
58 dev_id flash_blocks_num flash_si 58 dev_id flash_blocks_num flash_size subsystem/
59 flash_access flash_data reset 59 flash_access flash_data reset uevent
60 60
61 Initially the C2port access is disabled since 61 Initially the C2port access is disabled since you hardware may have
62 such lines multiplexed with other devices so, 62 such lines multiplexed with other devices so, to get access to the
63 C2port, you need the command:: 63 C2port, you need the command::
64 64
65 # echo 1 > /sys/class/c2port/c2port0/access 65 # echo 1 > /sys/class/c2port/c2port0/access
66 66
67 after that you should read the device ID and r 67 after that you should read the device ID and revision ID of the
68 connected micro controller:: 68 connected micro controller::
69 69
70 # cat /sys/class/c2port/c2port0/dev_id 70 # cat /sys/class/c2port/c2port0/dev_id
71 8 71 8
72 # cat /sys/class/c2port/c2port0/rev_id 72 # cat /sys/class/c2port/c2port0/rev_id
73 1 73 1
74 74
75 However, for security reasons, the in-system f 75 However, for security reasons, the in-system flash access in not
76 enabled yet, to do so you need the command:: 76 enabled yet, to do so you need the command::
77 77
78 # echo 1 > /sys/class/c2port/c2port0/flash_a 78 # echo 1 > /sys/class/c2port/c2port0/flash_access
79 79
80 After that you can read the whole flash:: 80 After that you can read the whole flash::
81 81
82 # cat /sys/class/c2port/c2port0/flash_data > 82 # cat /sys/class/c2port/c2port0/flash_data > image
83 83
84 erase it:: 84 erase it::
85 85
86 # echo 1 > /sys/class/c2port/c2port0/flash_e 86 # echo 1 > /sys/class/c2port/c2port0/flash_erase
87 87
88 and write it:: 88 and write it::
89 89
90 # cat image > /sys/class/c2port/c2port0/flas 90 # cat image > /sys/class/c2port/c2port0/flash_data
91 91
92 after writing you have to reset the device to 92 after writing you have to reset the device to execute the new code::
93 93
94 # echo 1 > /sys/class/c2port/c2port0/reset 94 # echo 1 > /sys/class/c2port/c2port0/reset
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