Blame view

bootloader/u-boot_2015_04/doc/README.imx6 2.01 KB
6b13f685e   김민수   BSP 최초 추가
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
  U-Boot for Freescale i.MX6
  
  This file contains information for the port of U-Boot to the Freescale i.MX6
  SoC.
  
  1. CONVENTIONS FOR FUSE ASSIGNMENTS
  -----------------------------------
  
  1.1 MAC Address: It is stored in fuse bank 4, with the 32 lsbs in word 2 and the
      16 msbs in word 3.
  
  Example:
  
  For reading the MAC address fuses on a MX6Q:
  
  - The MAC address is stored in two fuse addresses (the fuse addresses are
  described in the Fusemap Descriptions table from the mx6q Reference Manual):
  
  0x620[31:0] - MAC_ADDR[31:0]
  0x630[15:0] - MAC_ADDR[47:32]
  
  In order to use the fuse API, we need to pass the bank and word values, which
  are calculated as below:
  
  Fuse address for the lower MAC address: 0x620
  Base address for the fuses: 0x400
  
  (0x620 - 0x400)/0x10 = 0x22 = 34 decimal
  
  As the fuses are arranged in banks of 8 words:
  
  34 / 8 = 4 and the remainder is 2, so in this case:
  
  bank = 4
  word = 2
  
  And the U-boot command would be:
  
  => fuse read 4 2
  Reading bank 4:
  
  Word 0x00000002: 9f027772
  
  Doing the same for the upper MAC address:
  
  Fuse address for the upper MAC address: 0x630
  Base address for the fuses: 0x400
  
  (0x630 - 0x400)/0x10 = 0x23 = 35 decimal
  
  As the fuses are arranged in banks of 8 words:
  
  35 / 8 = 4 and the remainder is 3, so in this case:
  
  bank = 4
  word = 3
  
  And the U-boot command would be:
  
  => fuse read 4 3
  Reading bank 4:
  
  Word 0x00000003: 00000004
  
  ,which matches the ethaddr value:
  => echo ${ethaddr}
  00:04:9f:02:77:72
  
  Some other useful hints:
  
  - The 'bank' and 'word' numbers can be easily obtained from the mx6 Reference
  Manual. For the mx6quad case, please check the "46.5 OCOTP Memory Map/Register
  Definition" from the "i.MX 6Dual/6Quad Applications Processor Reference Manual,
  Rev. 1, 04/2013" document. For example, for the MAC fuses we have:
  
  Address:
  21B_C620	Value of OTP Bank4 Word2 (MAC Address)(OCOTP_MAC0)
  
  21B_C630	Value of OTP Bank4 Word3 (MAC Address)(OCOTP_MAC1)
  
  - The command '=> fuse read 4 2 2' reads the whole MAC addresses at once:
  
  => fuse read 4 2 2
  Reading bank 4:
  
  Word 0x00000002: 9f027772 00000004