Re: [Etherboot-developers] booting non linux images

[Ken Y. <ke...@bi...>]

Etherboot users taken off recipients as they are probably not
interested.

>1. memtest86.bin contains 512 bytes of boot sector, 2048 bytes of
>   of setup and the "real" code.

So the layout looks like a Linux kernel. What happens if you run
mknbi-linux on it as if it were a Linux kernel? After all LILO likes it
too.

>2. The os loads bootsector to the standard location (0x7c00) and
>   transfers control to it.
>
>3. The code in the boot sector duplicates itself at 0x90000 and jumps
>   to the new location. It loads setup at 0x90200 (does it load the
>   rest of the code at 0x10000?) and transfers control to the setup.

Looking more and more like a Linux kernel setup.

>4. Setup does necessary initilizations, detects memory etc. (does it
>   handle the loading of the rest) and transfers control to
>   0x10000.
>
>5. The code at 0x10000 moves the code in relo.out to memory above 0x100000
>   etc. but we don't have to worry about this.

Looks very familiar.

>Now about tagged image...
>
>1. First I write four bytes containing the magic number.
>
>2. Then I write the header of the tagged image so that the tagged image
>   contains two sections (setup and the rest of the code) and the starting
>   and loading address of setup is given as 0x902000?

Don't deal with raw bits like this, there are methods defined to handle
the file format transparently. But first try running mknbi-linux on it
as if it were a Linux kernel.