tool: improve emulation of kernel boot #276
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One of the things the tool has to do is emulate the kernel boot process, this involves getting a layout of all memory and putting into two categories, 'device' memory and 'normal' memory as defined by the kernel. The way we do this currently is by looking at certain symbols in the kernel ELF that encode this information. This doesn't work well when the compiler decides to optimise that symbol out and instead embed the information directly into where it's being used in the kernel code. So, instead we use the `platform_gen.json` file that gets generated by the kernel build system to get the same information. There should be no difference at all in terms of what the tool actually spits out at the end, it just means that the process of doing this emulation is less fragile. Signed-off-by: Ivan-Velickovic <i.velickovic@unsw.edu.au>
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Signed-off-by: Ivan-Velickovic <i.velickovic@unsw.edu.au>
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One of the things the tool has to do is emulate the kernel boot process, this involves getting a layout of all memory and putting into two categories, 'device' memory and 'normal' memory as defined by the kernel.
The way we do this currently is by looking at certain symbols in the kernel ELF that encode this information. This doesn't work well when the compiler decides to optimise that symbol out and instead embed the information directly into where it's being used in the kernel code.
So, instead we use the
platform_gen.jsonfile that gets generated by the kernel build system to get the same information.There should be no difference at all in terms of what the tool actually spits out at the end, it just means that the process of doing this emulation is less fragile.
Closes #35.
Depends on seL4/seL4#1390 first.