| Mikael Starvik | 51533b6 | 2005-07-27 11:44:44 -0700 | [diff] [blame] | 1 | Creation of the self-extracting compressed kernel image (vmlinuz) |
| 2 | ----------------------------------------------------------------- |
| Mikael Starvik | 51533b6 | 2005-07-27 11:44:44 -0700 | [diff] [blame] | 3 | |
| 4 | This can be slightly confusing because it's a process with many steps. |
| 5 | |
| 6 | The kernel object built by the arch/etrax100/Makefile, vmlinux, is split |
| 7 | by that makefile into text and data binary files, vmlinux.text and |
| 8 | vmlinux.data. |
| 9 | |
| 10 | Those files together with a ROM filesystem can be catted together and |
| 11 | burned into a flash or executed directly at the DRAM origin. |
| 12 | |
| 13 | They can also be catted together and compressed with gzip, which is what |
| 14 | happens in this makefile. Together they make up piggy.img. |
| 15 | |
| 16 | The decompressor is built into the file decompress.o. It is turned into |
| 17 | the binary file decompress.bin, which is catted together with piggy.img |
| 18 | into the file vmlinuz. It can be executed in an arbitrary place in flash. |
| 19 | |
| 20 | Be careful - it assumes some things about free locations in DRAM. It |
| 21 | assumes the DRAM starts at 0x40000000 and that it is at least 8 MB, |
| 22 | so it puts its code at 0x40700000, and initial stack at 0x40800000. |
| 23 | |
| 24 | -Bjorn |