projects / J-u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 96e1d75b HS |
1 | SHA1 usage: |
| 2 | ----------- | |
| 3 | ||
| 4 | In the U-Boot Image for the pcs440ep board is a SHA1 checksum integrated. | |
| 5 | This SHA1 sum is used, to check, if the U-Boot Image in Flash is not | |
| 6 | corrupted. | |
| 7 | ||
| 8 | The following command is available: | |
| 9 | ||
| 10 | => help sha1 | |
| 11 | sha1 address len [addr] calculate the SHA1 sum [save at addr] | |
| 12 | -p calculate the SHA1 sum from the U-Boot image in flash and print | |
| 13 | -c check the U-Boot image in flash | |
| 14 | ||
| 15 | "sha1 -p" | |
| 16 | calculates and prints the SHA1 sum, from the Image stored in Flash | |
| 17 | ||
| 18 | "sha1 -c" | |
| 19 | check, if the SHA1 sum from the Image stored in Flash is correct | |
| 20 | ||
| 21 | ||
| 22 | It is possible to calculate a SHA1 checksum from a memoryrange with: | |
| 23 | ||
| 24 | "sha1 address len" | |
| 25 | ||
| 26 | If you want to store a new Image in Flash for the pcs440ep board, | |
| 27 | which has no SHA1 sum, you can do the following: | |
| 28 | ||
| 29 | a) cp the new Image on a position in RAM (here 0x300000) | |
| 30 | (for this example we use the Image from Flash, stored at 0xfffa0000 and | |
| 31 | 0x60000 Bytes long) | |
| 32 | ||
| 33 | "cp.b fffa0000 300000 60000" | |
| 34 | ||
| 35 | b) Initialize the SHA1 sum in the Image with 0x00 | |
| 36 | The SHA1 sum is stored in Flash at: | |
| 6d0f6bcf | 37 | CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN + SHA1_SUM_POS |
| 239f05ee WD |
38 | for the pcs440ep Flash: 0xfffa0000 + 0x60000 + -0x20 |
| 39 | = 0xffffffe0 | |
| 40 | for the example in RAM: 0x300000 + 0x60000 + -0x20 | |
| 41 | = 0x35ffe0 | |
| 96e1d75b HS |
42 | |
| 43 | note: a SHA1 checksum is 20 bytes long. | |
| 44 | ||
| 45 | "mw.b 35ffe0 0 14" | |
| 46 | ||
| 47 | c) now calculate the SHA1 sum from the memoryrange and write | |
| 48 | the calculated checksum at the right place: | |
| 49 | ||
| 50 | "sha1 300000 60000 35ffe0" | |
| 51 | ||
| 52 | Now you have a U-Boot-Image for the pcs440ep board with the correct SHA1 sum. | |
| 53 | ||
| 6de80f21 SG |
54 | If you do a "buildman -k pcs440ep" or a "make all" to get the U-Boot image, |
| 55 | which will be found in ../current/ipam390/ - the correct SHA1 sum will be | |
| 56 | automagically included in the U-Boot image. | |
| 96e1d75b HS |
57 | |
| 58 | Heiko Schocher, 11 Jul 2007 |