25 lines
1.0 KiB
Plaintext
25 lines
1.0 KiB
Plaintext
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Creation of the self-extracting compressed kernel image (vmlinuz)
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-----------------------------------------------------------------
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This can be slightly confusing because it's a process with many steps.
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The kernel object built by the arch/etrax100/Makefile, vmlinux, is split
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by that makefile into text and data binary files, vmlinux.text and
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vmlinux.data.
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Those files together with a ROM filesystem can be catted together and
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burned into a flash or executed directly at the DRAM origin.
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They can also be catted together and compressed with gzip, which is what
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happens in this makefile. Together they make up piggy.img.
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The decompressor is built into the file decompress.o. It is turned into
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the binary file decompress.bin, which is catted together with piggy.img
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into the file vmlinuz. It can be executed in an arbitrary place in flash.
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Be careful - it assumes some things about free locations in DRAM. It
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assumes the DRAM starts at 0x40000000 and that it is at least 8 MB,
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so it puts its code at 0x40700000, and initial stack at 0x40800000.
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-Bjorn
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