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1 | Creation of the self-extracting compressed kernel image (vmlinuz) | ||
2 | ----------------------------------------------------------------- | ||
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 | ||